1Ax1 high molecular weight glutenin subunit (HMW-GS) gene expression cassette (GEC) lacking vector backbone sequences together with selectable marker Bar GEC were co-transformed into Chinese hexaploid cultivars Ee...1Ax1 high molecular weight glutenin subunit (HMW-GS) gene expression cassette (GEC) lacking vector backbone sequences together with selectable marker Bar GEC were co-transformed into Chinese hexaploid cultivars Een 1 and Emai 12 to test the feasibility and the efficiency of explant regeneration, transformation frequency and transgene expression comparing with whole vector transformation by the approaches of plasmid extraction and excision, immature embryo isolation, particle co-bombardment, tissue culture, DNA extraction, PCR amplification, southern hybridization, leaf-painting test and SDS-PAGE etc. No significant difference was shown in tissue culture response of the proportion of embryogenic calli, somatic embryogenesis and regeneration frequency between GEC and whole plasmid bombarded embryos, but both regenerated less well than non-bombarded control. Total 56 plantlets that survived PPT selection had insertion of at least the Bar gene, 18 were from the GEC treatment and 38 from the whole plasmid treatment, the escape ratio averaged 0.23. Six independent transplants f230 - f235 with GEC transformation from genotype Emai 12 presented clear PCR amplification bands of Bar and 1Ax1 gene. The transformation and co-transformation frequency were 3.51 and 100% respectively. PCR amplification using a primer-pair specific for ampicillin resistant gene indicated the existence of Amp^R gene in whole vectors but the removal in GECs and transplants. Southern blot of total DNA and PCR products from transgenic plants of 1Ax1 GEC confirmed the integration of the transgene 1Ax1 and the absence of the EcoR Ⅰ recognition site at both ends of the 1Ax1 GEC when integrated. SDS-PAGE showed the expression of 1Ax1 GEC and un-expression of whole plasmid. The length of integrated fragment, the proportion of the gene of interest (GOI) and the selectable marker (MG), bombardment pressure and genotypes are vital for the expression of a transformed GEC.展开更多
Pancreatic ductal adenocarcinoma(PDAC) is one of the most aggressive diseases and is characterized by high chemoresistance, leading to the lack of effective therapeutic approaches and grim prognosis. Despite increasin...Pancreatic ductal adenocarcinoma(PDAC) is one of the most aggressive diseases and is characterized by high chemoresistance, leading to the lack of effective therapeutic approaches and grim prognosis. Despite increasing understanding of the mechanisms of chemoresistance in cancer and the role of ATPbinding cassette(ABC) transporters in this resistance, the therapeutic potential of their pharmacological inhibition has not been successfully exploited yet. In spite of the discovery of potent pharmacological modulators of ABC transporters, the results obtained in clinical trials have been so far disappointing, with high toxicity levels impairing their successful administration to the patients. Critically, although ABC transporters have been mostly studied for their involvement in development of multidrug resistance(MDR), in recent years the contribution of ABC transporters to cancer initiation and progression has emerged as an important area of research, the understanding of which could significantly influence the development of more specific and efficient therapies. In this review, we explore the role of ABC transporters in the development and progression of malignancies, with focus on PDAC. Their established involvement in development of MDR will be also presented. Moreover, an emerging role for ABC transporters as prognostic tools for patients' survival will be discussed, demonstrating the therapeutic potential of ABC transporters in cancer therapy.展开更多
Rapid dissemination of antibiotic resistance genes among bacterial isolates is an increasing problem in China. Integron, a conserved DNA sequence, which is carried on episomal genetic structures, plays a very importan...Rapid dissemination of antibiotic resistance genes among bacterial isolates is an increasing problem in China. Integron, a conserved DNA sequence, which is carried on episomal genetic structures, plays a very important role in development of antibiotic resistance. This systematic analysis was based on MEDLINE and EMBASE databases. We summarized the distribution and proportion of different types of gene cassette arrays ofintegrons (including class 1, 2, 3 and atypical class 1 integron) from clinical bacteria isolates in China. Fifty-six literatures were included in this study. Most of the strains were Gram-negative bacteria (94.1%, 7,364/7,822) while only 5.9% strains were Gram- positive bacteria. Class 1 integrons were detected in 54.2% (3956/7295) Gram-negative strains, aadA2 was the most popular gene cassette array detected from 60 Gram-positive bacteria while dfrA 17-aadA5 were detected in 426 Gram- negative bacteria. This study identified 12 novel gene cassette arrays which have not been previously found in any species. All the novel gene cassette arrays were detected from Gram-negative bacteria. A regional characteristic of distribution of integrons was presented in this study. The results highlight a need for continuous surveillance of integrons and provide a guide for future research on integron-mediated bacteria resistance.展开更多
Purpose: In acute lymphoblastic leukemia (ALL), multidrug resistance is often mediated by AT- Pase Binding Cassette (ABC) proteins, which principally involve ABCC1 (multidrug resistance protein 1, MRP1) and ABCB1 (mul...Purpose: In acute lymphoblastic leukemia (ALL), multidrug resistance is often mediated by AT- Pase Binding Cassette (ABC) proteins, which principally involve ABCC1 (multidrug resistance protein 1, MRP1) and ABCB1 (multidrug resistance 1, MDR1). However, direct comparisons between the differential effects of ABCC1 and ABCB1 have been difficult, since identical cell lines with differential expression of these transporters have not been developed. Experimental Design: In this study, we developed and compared the biological profiles of Jurkat cell lines that selectively over-expressed ABCC1 and ABCB1. Vincristine (VCR) plays an important role in the treatment of T-lineage ALL (T-ALL), and is often the first drug given to newly-diagnosed patients. Because of its importance in treatment, we provide descalating, sub-lethal doses of VCR to Jurkat cells, and extended our observations to expression profiling of newly diagnosed patients with T-ALL. Results: We found that VCR-resistant cells over-expressed ABCC1 nearly 30-fold. The calcein AM assay confirmed that VCR-resistant cells actively extruded VCR, and that ABCC1-mediated drug resistance conferred a different spectrum of multidrug resistance than other T-ALL induction agents. siRNA experiments that blocked ABCC1 export confirmed that VCR resistance could be reversed in vitro. Analyses of T-lymphoblasts obtained from 100 newly diagnosed T-ALL patients treated on Children’s Oncology Group Phase III studies 9404 and AALL0434 that induction failure could be could be partially explained by the over-expression of ABCC1 and ABCB1. Conclusions: Taken together, these results suggest that over-expression of ABC transporters plays a contributing role in mediating treatment failure in T-ALL, and underscore the need to employ alternate treatment approaches in patients for whom induction failed or for those with relapsed disease.展开更多
The class 1 integron and complex gene cassettes among different species of clinical isolates in northern China were characterized in this study. 383 clinical isolates were obtained from northern China, and class 1 int...The class 1 integron and complex gene cassettes among different species of clinical isolates in northern China were characterized in this study. 383 clinical isolates were obtained from northern China, and class 1 integrons containing gene cassettes widely distributed among gram negative clinical isolates was observed. We find that the class 1 integron showed positive correlation with multidrug resistance phenotype of gram negative bacteria. In addition, we find that isolates belonged to one species harbored different types of gene cassette arrays, while same types of gene cassette arrays were observed in different species of isolates. The diversity of gene cassette arrays among the isolates indicated the complexity of multidrug resistance in clinical isolates in northern China.展开更多
Objective: To analyze the molecular mechanism of integron mediated mulfi-resistanc, e in an ESBL-producing K. pneumoniae NJ 12 isolate. Methods: Susceptibility test was carried out by Kirby-Bauer method. Class Ⅰ, ...Objective: To analyze the molecular mechanism of integron mediated mulfi-resistanc, e in an ESBL-producing K. pneumoniae NJ 12 isolate. Methods: Susceptibility test was carried out by Kirby-Bauer method. Class Ⅰ, Ⅱ and Ⅲ integrons were detected by integrase gene PCR with primers that annealed to conserved regions of integron-encoded integrase genes intll, intl2 and intl3. The variable region of integron was amplified by integron PCR with primers that targeted the conserved flanking regions, and the product was sequenced. Six aminoglycoside modifying-enzyme genes, including ant(2")-Ⅰ, ant(3")- Ⅰ, aac(3)- Ⅰ, aac(3)-Ⅱ, aac (6')-Ⅰ, and aac(6')-Ⅱ , were detected. Results: K. pneumoniae NJ 12 was resistant to nine antibiotics, including piperacillin, ampicillin, cefuroxime, ceftazidime, cefotaxime, aztreonam, streptomycin, gentamicin and amikacin. This isolate was shown that there was positive with class Ⅰ integron, ant(2")- Ⅰ , ant(3")- Ⅰ , aac(3)-Ⅱ and aac(6')- Ⅰ modifying-enzyme genes. Neither class Ⅱ nor Ⅲ integron was detected; DNA sequencing of the fragment amplified by integron PCR revealed a novel cassette array aadR-cat-blaoxa-10/ aadA1. Conclusion: Class I integron with a novel cassette array in an ESBL-producing multidrug-resistant K. pneumon/ae NJ 12 isolate was reported from Nanjing area of China, with the GenBank accession number DQ141319.展开更多
Atherosclerosis is the most common cause of cardiovascular diseases, such as myocardial infarction and stroke. The aim of this study was to investigate the effects of a novel compound ZBM30 on atherosclerosis in ApoE-...Atherosclerosis is the most common cause of cardiovascular diseases, such as myocardial infarction and stroke. The aim of this study was to investigate the effects of a novel compound ZBM30 on atherosclerosis in ApoE- deficient mice and its associated mechanism. ApoE-deficient mice (6 weeks old), fed an atherogenic high-fat and high cholesterol diet for 8 weeks, were divided into three groups. Two groups were orally administrated ZBM30 (10, 30 nag ~ kg-1) daily for 12 weeks, while the control group was administered saline. Atherosclerotic lesions with en face aortas were evaluated by Sudan IV staining, and lesion areas in aortic sinuses were evaluated by oil red O staining. Necrotic core areas and fibrous cap areas in the lesion were evaluated by henaatoxylin and eosin (HE) staining and Masson' s trichronae staining in the aorta sinuses. The effects of ZBM30 on cholesterol accumulation in naacrophages and cholesterol transporters: ATP binding cassette A1 (ABCA1) and ATP binding cassette G1 (AB- CG1) were evaluated by oil red O assay, 3H-cholesterol efflux assay, Western blot, and real-time PCR on macro- phage cell lines: Raw 264.7 and THP-1. Inanauno-fluoresces was used to determine the ABCA1 expression in naac- rophage in aorta sinuses. Luciferase reporters of wild type and mutant types of ABCA1 promoter were constructed to determine the regulatory domain of ZBM30 on ABCA1 promoter. Results showed that, compared with the control group, en face lesions in ZBM30 group ( 10, 30 mg · kg^-1 ) were reduced 54.96 ± 10.06% and 71.50 ± 15.37% respectively, and aorta sinus lesions were reduced 41.85 ± 11.21% and 82.23 ± 8.25% respectively. Necrotic core areas in the ZBM30 group were markedly reduced and fibrous cap areas were not changed. Oil red O staining and 3 H-cholesterol efflux assays on Raw 264.7 cell line revealed that ZBM30 significantly attenuated the cholesterol accumulation in naacrophages by enhancing apolipoprotein AI and HDL mediated cholesterol efflux. Furthermore, ZBM30 induced the protein and naRNA expression of cholesterol transporters such as ABCA1 and ABCG1. Inanauno- fluoresces experiment revealed that ZBM30 induced the ABCA1 expression in naacrophage in the lesion, which is consistent with the results in vitro. Luciferase reporter assay revealed that ZBM30 exerted its effect on ABCA1 via liver X receptor (LXR) binding domain. In conclusion, ZBM30 suppresses atherosclerosis through up-regulating cholesterol efflux via ABCA1 and ABCG1 transporters in ApoE-deficient mice.展开更多
Objective: To investigate the molecular epidemiology and antimicrobial resistance patterns of methicillin-resistant Staphylococcus aureus(MRSA) among healthcare workers and patients.Methods: MRSA isolates were recover...Objective: To investigate the molecular epidemiology and antimicrobial resistance patterns of methicillin-resistant Staphylococcus aureus(MRSA) among healthcare workers and patients.Methods: MRSA isolates were recovered from nasal swabs collected at a tertiary care hospital of Nepal and confirmed on the basis of Gram staining, conventional biochemical tests, and PCR amplification of mec A gene. PCRs were also used for detection of the different resistance genes and staphylococcal cassette chromosome(SCC) mec types.Antibiotic susceptibility patterns of isolates were assessed by disc diffusion method and minimum inhibitory concentrations were determined by E-test.Results: A total of 29 MRSA were isolated from 536 nasal swabs(5.4%) of health care workers and patients at a tertiary care hospital in Nepal. All isolates were susceptible to amikacin, gentamicin, vancomycin(minimal inhibitory concentrations < 2 mg/m L), tigecycline, tetracycline, nitrofurantoin, rifampicin, quinupristin-dalfopristin, and linezolid. Among the 29 MRSA isolates, resistance to erythromycin(72%), ciprofloxacin(75%), co-trimoxazole(62%), clindamycin(10%), and chloramphenicol(10%) was found, and fifteen isolates(51%)exhibited high-level mupirocin resistance(minimal inhibitory concentrations > 1 024 mg/m L).Fourteen isolates were found harboring the mup A gene and one isolate was found carrying the novel mup B gene. High prevalence(68%) of SCCmec I type was found, followed by SCCmec V(13%) and SCCmec III(3%) among all the MRSA isolates.Conclusions: We found the emergence of SCCmec type I with high-level mupirocin resistance among MRSA in Nepal. Data also suggest that MRSA SCCmec type V strain has spread from the community to the hospital.展开更多
Objective: To construct the small interfering RNA(siRNA) expression cassettes (SECs) targeting activated K-ras gene sequence and investigate the effects of SECs on K-ras gene in human pancreatic cancer cell line MIAPa...Objective: To construct the small interfering RNA(siRNA) expression cassettes (SECs) targeting activated K-ras gene sequence and investigate the effects of SECs on K-ras gene in human pancreatic cancer cell line MIAPaCa-2. Methods: Three different sites of SECs were constructed by PCR. The K1/siRNA, K2/siRNA and K3/siRNA were located at the site 194, 491 and 327, respectively. They were transfected into MiaPaCa-2 cells by liposome to inhibit the expression of activated K-ras. In the interfering groups of site 194,491, we observed the cytopathic effect of confluent MiaPaCa-2 cells after they were incubated for 48 hours, and detected the apoptosis in cells by FACS, then we tested the alternation of K-ras gene in confluent MiaPaCa-2 cells by RT-PCR,immunofluorescence and western blot, respectively. Results: Introductions of the K1/siRNA and K2/siRNA against K-ras into MiaPaCa-2 cells led to cytopathic effect, slower proliferation and increased apoptosis, while the appearances of control MiaPaCa-2 cells remained well. The number of apoptotic cells increased compared with control cells. RT-PCR,immunofluorescence and western blot showed the effects of inhibited expression of activated K-ras gene by RNA interference in the K1/siRNA and K2/siRNA groups. We also found that the introduction of K3/siRNA had no effect on MiaPaCa-2 cells. Conclusion: K1/siRNA and K2/siRNA can inhibit the expression of activated K-ras and decrease the growth of MiaPaCa-2 cells, while K3/siRNA has no such effect, demonstrating that the suppression of tumor growth by siRNA is sequence-specific. We conclude that K-ras is involved in maintenance of tumor growth of human pancreatic cancer, and SECs against K-ras expression may be a powerful tool to be used therapeutically against human pancreatic cancer.展开更多
Objective: To study the role of nuclear factor-kappa B(NF- κB) in cholesterol efflux from THP-1 derived-foam cells treated with Angiotensin Ⅱ(Ang Ⅱ ). Methods:Cultured THP-1 derived-foam cells were treated wi...Objective: To study the role of nuclear factor-kappa B(NF- κB) in cholesterol efflux from THP-1 derived-foam cells treated with Angiotensin Ⅱ(Ang Ⅱ ). Methods:Cultured THP-1 derived-foam cells were treated with Ang Ⅱ or preincubated with tosyl-phenylalanine chloromethyl-ketone(TPCK) NF- κB inhibitor. The levels of activated NF- κB in the cells were examined by sandwich ELISA, Cellular cholesterol content was studied by electron microscopy scanning and zymochemistry via fluorospectrophotometer and cholesterol effiux was detected by scintillation counting technique. ABCA1 mRNA and protein were quantified by RT-PCR and Western blotting. Results:Addition of TPCK to the cells before Ang Ⅱ stimulation attenuated the response of NF- κB p65 nuclear translocation induced by Ang Ⅱ and showed no peak in foam cells group and caused a reduction in cholesterol content and an increase in cholesterol efflux by 24.1%(P〈 0.05) and 41.1%(P〈 0.05) respectively, when compared with Ang Ⅱ group. In accordance, the ABCA1 mRNA and protein were increased by 30% and 19%(P 〈 0.05) respectively, when compared with Ang Ⅱ group. Conclusion:Ang Ⅱ can downregulate ABCA1 in THP-1 derived-foam cells via NF- K B, which leads to less cholesterol effiux and the increase of cholesterol content with the consequence of the promotion of atherosclerosis.展开更多
The coagulase-negative staphylococci (CoNS) have long been considered to be low pathogenicity. The possibility of a horizontal transfer of resistance and virulence genes from S. aureus to CoNS could increase the patho...The coagulase-negative staphylococci (CoNS) have long been considered to be low pathogenicity. The possibility of a horizontal transfer of resistance and virulence genes from S. aureus to CoNS could increase the pathogenicity of these bacteria. The objective of this work is to contribute to a better knowledge of the pathogenicity of (CoNS) strains isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi/Sô-Ava. Seventy strains of CoNS isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi were tested for methicillin resistance. The resistance to methicillin was evaluated phenotypically by the resistance of the strains to cefoxitin and then confirmed by the search for the mecA gene using PCR. The genes encoding staphylococcal chromosomal cassette (SCCmec) types I, II and III originally found in S. aureus were tested in CoNS by multiplex PCR using specific primers. All the strains studied showed resistance to methicillin. However, only 28.5% (20/70) carried the mecA gene. SCCmec was identified in only 17.14% (12/70) of these strains. Four strains carried mecA gene as well as one of the three types of SCCmec searched. SCCmec types I, II and III were identified in CoNS strains studied. SCCmec type I was the most frequent chromosomal cassette in mecA<sup>+</sup> strains, only or in association with another SCCmec. The study also revealed methicillin-resistant strains carrying SCCmec lacking the mecA gene. Finally, 60% (12/20) of the strains were found to be non-typeable. Our results show that CoNS strains present a high resistance to methicillin and the source of this resistance in the CoNS of our study is not only the mecA gene. There is also a high diversity of SCCmec, justified by a large number of non-typeable CoNS strains. The mecA<sup>−</sup> SCCmec<sup>+</sup> methicillin-resistant strains deserve to be sequenced for further studies.展开更多
Pseudomonas aeruginosa is one of the most important opportunistic human pathogens worldwide. High prevalence of Multi Drug Resistant P. aeruginosa (MDRPa) in Iran is a serious problem for antimicrobial therapy. Severa...Pseudomonas aeruginosa is one of the most important opportunistic human pathogens worldwide. High prevalence of Multi Drug Resistant P. aeruginosa (MDRPa) in Iran is a serious problem for antimicrobial therapy. Several studies have reported the MDRPa in Europe and Asia. Due to the use of broad-spectrum antibiotics, bacterial resistance is increasing in Iran, located in Middle East. The present cross-sectional study was designed to investigate the prevalence of class1 integron, resistance gene cassettes and antimicrobial susceptibility profiles among isolates of P. aeruginosa in Al-Zahra Hospital, Isfahan City, central part of Iran from Jan-Sep 2014. The aim of this study was to determine the antimicrobial susceptibility, the prevalence of Class1 integron, resistance gene a measuring in Iran. A total of 231 P. aeruginosa isolates were collected from clinical specimens including urine (50.6%), tracheal tube (25.5%), wound (13.4%), blood (6.1%), catheter (2.2%), cerebrospinal fluid (1.7%) and sputum (0.4%) isolates from hospitalized patients (mean age: 50.27 ± 24.12 years).The majority of patients (68%) were male. Isolates were collected from different parts of the hospital as follows: ICU, Internal Medicine, Emergency care, Pediatrics, Nephrology, Transplant Center, General surgery and Infectious. Revealed data show a high rate of MDR P. aeruginosa isolates in the studied area;also, the result signifies the spread of aadA6 among clinical isolates in hospitalized patients.展开更多
OBJECTIVE: To evaluate the efficacy of Shoushen granule, prepared with four Chinese medicinals, on the targeted regulation of adenosine triphosphate binding cassette transporter A1(ABCA1) through proprotein convertase...OBJECTIVE: To evaluate the efficacy of Shoushen granule, prepared with four Chinese medicinals, on the targeted regulation of adenosine triphosphate binding cassette transporter A1(ABCA1) through proprotein convertase subtilisin/kexin type 9(PCSK9) and toll-like receptor 4(TLR4)/nuclear factor kappa-B(NF-κB) signaling pathway to affect atherosclerosis(AS) in ApoE-knockout(ApoE-/-) mice.METHODS: ApoE-/-mice fed with a high-fat diet were used for AS modeling and divided into Model,Shoushen, and Atorvastatin groups. C57 BL/6 J mice at the same age and background strain were included in the Control group. Western blot and immunohistochemistry were used to measure ABCA1, PCSK9, TLR4, and NF-κB protein expression in mouse aortas. Enzyme-linked immuno sorbent assay was used to measure mouse serum tumor necrosis factor-α(TNF-α), interleukin-10(IL-10), monocyte chemoattractant protein 1(MCP-1), and intercellular cell adhesion molecule-1(ICAM-1) expression. Serum lipid profiles and histopathology were also assessed. Shoushen granule were composed of Heshouwu(Radix Polygoni Multiflori) 15 g, Gouqizi(Fructus Lycii) 15 g, Sheng shanzha(Raw Fructus Crataegus Pinnatifidae) 10 g, and Sanqi(Radix Notoginseng) 3 g.RESULTS: ApoE-/-mice fed with a high-fat diet had notable AS lesions, with reduced ABCA1 and IL-10 levels, elevated PCSK9, TLR4, NF-κB, TNF-α, MCP-1,and ICAM-1 expression, and increased total cholesterol(TC) and low density lipoprotein cholesterol(LDL-C) contents. With drug interventions, the areas of AS plaques were significantly reduced,the ABCA1 and IL-10 levels were increase, while the PCSK9, TLR4, NF-κB, TC, and LDL-C contents,and the TNF-α, MCP-1, and ICAM-1 expression were reduced.CONCLUSION: Shoushen granule effectively interfered with AS development by antagonizing the expression of key factors of the PCSK9 and TLR4/NF-κB signaling pathway to upregulate ABCA1 expression.展开更多
Nicotiana species of the section Alatae characteristically emit the floral scent compounds of the 'cineole cassette' comprising 1,8-cineole, limonene, myrcene, α-pinene, β-pinene, sabinene, and α-terpineol. We su...Nicotiana species of the section Alatae characteristically emit the floral scent compounds of the 'cineole cassette' comprising 1,8-cineole, limonene, myrcene, α-pinene, β-pinene, sabinene, and α-terpineol. We successfully isolated genes of Nicotiana alata and Nicotiana langsdorfii that encoded enzymes, which produced the characteristic monoter- penes of this 'cineole cassette' with α-terpineol being most abundant in the volatile spectra. The amino acid sequences of both terpineol synthases were 99% identical. The enzymes cluster in a monophyletic branch together with the closely related cineole synthase of Nicotiana suaveolens and monoterpene synthase 1 of Solanum lycopersicum. The cyclization reactions (α-terpineol to 1,8-cineole) of the terpineol synthases of N. alata and N. langsdorfii were less efficient compared to the 'cineole cassette' monoterpene synthases of Arabidopsis thaliana, N. suaveolens, Salvia fruticosa, Salvia officinalis, and Citrus unshiu. The terpineol synthases of IV. alata and N. langsdorfii were localized in pistils and in the adaxial and abaxial epidermis of the petals. The enzyme activities reached their maxima at the second day after anthesis when flowers were fully opened and the enzyme activity in N. alata was highest at the transition from day to night (diurnal rhythm).展开更多
In this study,326 Escherichia coli isolates from food animals collected during the last four decades in China were characterized using antimicrobial susceptibility testing and screening for integrons/cassettes.Minimum...In this study,326 Escherichia coli isolates from food animals collected during the last four decades in China were characterized using antimicrobial susceptibility testing and screening for integrons/cassettes.Minimum inhibitory concentration(MIC) testing indicated that the antimicrobial resistance of E.coli has increased since the 1970s.The findings of this study present a warning to veterinary practitioners about the excessive use of antimicrobials,and suggest the necessity for surveillance and control of antimicrobial resistance in veterinary clinical medicine in China.展开更多
P-glycoprotein(ABCB1),multidrug resistance protein-1(ABCC1)and breast cancer resistance protein(ABCG2)belong to the ATP-binding cassette(ABC)superfamily of proteins that play an important physiological role in protect...P-glycoprotein(ABCB1),multidrug resistance protein-1(ABCC1)and breast cancer resistance protein(ABCG2)belong to the ATP-binding cassette(ABC)superfamily of proteins that play an important physiological role in protection of the body from toxic xenobiotics and endogenous metabolites.Beyond this,these transporters determine the toxicity profile of many drugs,and confer multidrug resistance(MDR)in cancer cells associated with a poor treatment outcome of cancer patients.It has long been hypothesized that inhibition of ABC drug efflux transporters will increase drug accumulation and thereby overcome MDR,but until now no approved inhibitor of these transporters is available in the clinic.In this review we present molecular strategies to overcome this type of drug resistance and discuss for each of these strategies their promising value or indicate underlying reasons for their limited success.展开更多
Importance: The ATP-binding cassette subfamily A member 3 (ABCA3) protein plays a vital role in surfactant homeostasis. Mutations in the ABCA3 gene lead to the development of interstitial lung disease. In the most sev...Importance: The ATP-binding cassette subfamily A member 3 (ABCA3) protein plays a vital role in surfactant homeostasis. Mutations in the ABCA3 gene lead to the development of interstitial lung disease. In the most severe manifestation, mutations can lead to a fatal respiratory distress syndrome in neonates. ABCA3 belongs to the same ATP-binding cassette transporter superfamily as the cystic fibrosis transmembrane conductance regulator (CFTR), the gene that causes cystic fibrosis. Objective: To classify ABCA3 mutations in a manner similar to CFTR mutations in order to take advantage of recent advances in therapeutics. Methods: Sequence homology between the CFTR protein and the ABCA3 protein was established. The region of CFTR that is a target for the new potentiator class of drugs was of particular interest. We performed a literature search to obtain all published mutations that were thought to be disease causing. We classified these mutations using the established CFTR classification system. When possible, we drew on previous experimental classification of ABCA3 mutations. Results: Although the proteins share the same overall structure, only a 19%identity was established between CFTR and ABCA3. The CFTR therapeutic target region has a 22% homology with the corresponding ABCA3 region. Totally 233 unique protein mutations were identified. All protein mutations were classified and mapped to a schematic diagram of the ABCA3 protein. Interpretation: This new classification system for ABCA3, based on CFTR classification, will likely aid further research of clinical outcomes and identification of mutation-tailored therapeutics, with the aim for improving clinical care for patients with ABCA3 mutations.展开更多
Objectives To explore the protective effect of irbesartan (lrb) under the interference with angiotensin II (Ang II) on ABCA1. Methods Electron microscopy was used to detect the morphous of foam cells. The expressi...Objectives To explore the protective effect of irbesartan (lrb) under the interference with angiotensin II (Ang II) on ABCA1. Methods Electron microscopy was used to detect the morphous of foam cells. The expression of ABCA1 mRNA and its protein were determined by RT-PCR and Western blotting, respectively. The variance of cellular cholesterol content was measured by zymochemistry via-fluorospeetrophotometer. Results A positive facilitative effect of Ang II on the formation of foam cells was observed. Total cholesterol was increased significantly by Ang II, the expression of ABCA1 was down-regulated obviously by Ang II; Irb could protect ABCA1 against the lesion of Ang II; Total cellular cholesterol content was reduced significantly in Irb + Ang II group; However, considerable alteration about the cholesterol content and the expression of ABCA1 were not observed in Irb group without incubation with Ang II. Conclusions Irb could protect ABCA1 against the lesion of Ang II, which may contribute to its anti-atherosclerotic properties. ( S Chin J Cardiol 2009; 10(4) : 227 -233)展开更多
BACKGROUND Patients with obstructive jaundice caused by intrahepatic bile duct stones can be effectively managed by surgery.However,some patients may develop postope-rative complications,liver failure,and other life-t...BACKGROUND Patients with obstructive jaundice caused by intrahepatic bile duct stones can be effectively managed by surgery.However,some patients may develop postope-rative complications,liver failure,and other life-threatening situations.Here,we report a patient with mutations in the uridine 5’-diphospho-glucuronosyltrans-ferase 1A1(UGT1A1)and bile salt export pump(adenosine triphosphate-binding cassette subfamily B member 11,ABCB11)genes who presented multiple intrahe-patic bile duct stones and cholestasis,and the jaundice of the patient increased after partial hepatectomy.CASE SUMMARY A 52-year-old male patient admitted to the hospital on October 23,2021,with a progressive exacerbation of jaundice,was found to have multiple intrahepatic bile duct stones with the diagnoses of obstructive jaundice and acute cholecystitis.Subsequently,the patient underwent left hepatectomy with biliary exploration,stone extraction,T-tube drainage,and cholecystectomy without developing any intraoperative complications.The patient had a dark urine color with worsening jaundice postoperatively and did not respond well to plasma exchange and other symptomatic and supportive treatments.Since the progressive increase in postoperative bilirubin could not be clinically explained with any potential reason,including,if not at all,viral infection,cholangitis,autoimmune liver disease,and other causes,the patient underwent whole-exon screening for any genetic diseases,which surprisingly identified UGT1A1 and ABCB11 gene mutations related to glucuronidation of indirect bilirubin as well as bile acid transport in hepatocytes,respectively.Thus,we hypothesized that postoperative refractory cholestasis might result from UGT1A1 and ABCB11 gene mutations and further recommended liver transplantation to the patient,who eventually declined it and died from liver failure six months later.CONCLUSION Surgery may aggravate cholestasis in patients with multiple intrahepatic bile duct stones and cholestasis associated with UGT1A1 and ABCB11 gene mutations.A liver transplant may be the best option if active medical treatment fails.展开更多
Zinc(Zn) is an essential trace mineral that is required for plant growth and development. A number of protein transporters, which are involved in Zn uptake, translocation and distribution, are finely regulated to main...Zinc(Zn) is an essential trace mineral that is required for plant growth and development. A number of protein transporters, which are involved in Zn uptake, translocation and distribution, are finely regulated to maintain Zn homeostasis in plant. In this study, we functionally characterized an ATP-binding cassette(ABC) transporter gene, OsPDR7, which is involved in Zn homeostasis. Os PDR7 encodes a plasma membrane-localized protein that is expressed mainly in the exodermis and xylem in the rice root.ospdr7 mutants resulted in higher Zn accumulation compared with the wild type. Heterogeneous expression of OsPDR7 in a yeast mutant rescued the Zn-deficiency phenotype, implying transport activity of OsPDR7 to Zn in yeast. However, no ZIP genes except for OsZIP9 showed change in expression profile in the ospdr7 mutants, which suggested that OsPDR7 maintains cellular Zn homeostasis through regulating Os ZIP9 expression. RNA-Seq analysis further revealed a set of differentially expressed genes between the wild type and ospdr7 mutants that allowed us to propose a possible OsPDR7-associated signaling network involving transporters, hormone responsive genes, and transcription factors. Our results revealed a novel transporter involved in the regulation of Zn homeostasis and will pave the way toward a better understanding of the fine-tuning of gene expression in the network of transporter genes.展开更多
基金supported by China Post-Doctorial Foundation(2002031255)Rothamsted International Foundation(2002)of the UKNatural Science Foundation of Zhejiang Province,China(M303081).
文摘1Ax1 high molecular weight glutenin subunit (HMW-GS) gene expression cassette (GEC) lacking vector backbone sequences together with selectable marker Bar GEC were co-transformed into Chinese hexaploid cultivars Een 1 and Emai 12 to test the feasibility and the efficiency of explant regeneration, transformation frequency and transgene expression comparing with whole vector transformation by the approaches of plasmid extraction and excision, immature embryo isolation, particle co-bombardment, tissue culture, DNA extraction, PCR amplification, southern hybridization, leaf-painting test and SDS-PAGE etc. No significant difference was shown in tissue culture response of the proportion of embryogenic calli, somatic embryogenesis and regeneration frequency between GEC and whole plasmid bombarded embryos, but both regenerated less well than non-bombarded control. Total 56 plantlets that survived PPT selection had insertion of at least the Bar gene, 18 were from the GEC treatment and 38 from the whole plasmid treatment, the escape ratio averaged 0.23. Six independent transplants f230 - f235 with GEC transformation from genotype Emai 12 presented clear PCR amplification bands of Bar and 1Ax1 gene. The transformation and co-transformation frequency were 3.51 and 100% respectively. PCR amplification using a primer-pair specific for ampicillin resistant gene indicated the existence of Amp^R gene in whole vectors but the removal in GECs and transplants. Southern blot of total DNA and PCR products from transgenic plants of 1Ax1 GEC confirmed the integration of the transgene 1Ax1 and the absence of the EcoR Ⅰ recognition site at both ends of the 1Ax1 GEC when integrated. SDS-PAGE showed the expression of 1Ax1 GEC and un-expression of whole plasmid. The length of integrated fragment, the proportion of the gene of interest (GOI) and the selectable marker (MG), bombardment pressure and genotypes are vital for the expression of a transformed GEC.
文摘Pancreatic ductal adenocarcinoma(PDAC) is one of the most aggressive diseases and is characterized by high chemoresistance, leading to the lack of effective therapeutic approaches and grim prognosis. Despite increasing understanding of the mechanisms of chemoresistance in cancer and the role of ATPbinding cassette(ABC) transporters in this resistance, the therapeutic potential of their pharmacological inhibition has not been successfully exploited yet. In spite of the discovery of potent pharmacological modulators of ABC transporters, the results obtained in clinical trials have been so far disappointing, with high toxicity levels impairing their successful administration to the patients. Critically, although ABC transporters have been mostly studied for their involvement in development of multidrug resistance(MDR), in recent years the contribution of ABC transporters to cancer initiation and progression has emerged as an important area of research, the understanding of which could significantly influence the development of more specific and efficient therapies. In this review, we explore the role of ABC transporters in the development and progression of malignancies, with focus on PDAC. Their established involvement in development of MDR will be also presented. Moreover, an emerging role for ABC transporters as prognostic tools for patients' survival will be discussed, demonstrating the therapeutic potential of ABC transporters in cancer therapy.
基金funded by the National Natural Science Foundation of China(No.81000754 and No. 81471994)received a grant from the Key Laboratory for Laboratory Medicine of Jiangsu Province of China(No.XK201114)
文摘Rapid dissemination of antibiotic resistance genes among bacterial isolates is an increasing problem in China. Integron, a conserved DNA sequence, which is carried on episomal genetic structures, plays a very important role in development of antibiotic resistance. This systematic analysis was based on MEDLINE and EMBASE databases. We summarized the distribution and proportion of different types of gene cassette arrays ofintegrons (including class 1, 2, 3 and atypical class 1 integron) from clinical bacteria isolates in China. Fifty-six literatures were included in this study. Most of the strains were Gram-negative bacteria (94.1%, 7,364/7,822) while only 5.9% strains were Gram- positive bacteria. Class 1 integrons were detected in 54.2% (3956/7295) Gram-negative strains, aadA2 was the most popular gene cassette array detected from 60 Gram-positive bacteria while dfrA 17-aadA5 were detected in 426 Gram- negative bacteria. This study identified 12 novel gene cassette arrays which have not been previously found in any species. All the novel gene cassette arrays were detected from Gram-negative bacteria. A regional characteristic of distribution of integrons was presented in this study. The results highlight a need for continuous surveillance of integrons and provide a guide for future research on integron-mediated bacteria resistance.
文摘Purpose: In acute lymphoblastic leukemia (ALL), multidrug resistance is often mediated by AT- Pase Binding Cassette (ABC) proteins, which principally involve ABCC1 (multidrug resistance protein 1, MRP1) and ABCB1 (multidrug resistance 1, MDR1). However, direct comparisons between the differential effects of ABCC1 and ABCB1 have been difficult, since identical cell lines with differential expression of these transporters have not been developed. Experimental Design: In this study, we developed and compared the biological profiles of Jurkat cell lines that selectively over-expressed ABCC1 and ABCB1. Vincristine (VCR) plays an important role in the treatment of T-lineage ALL (T-ALL), and is often the first drug given to newly-diagnosed patients. Because of its importance in treatment, we provide descalating, sub-lethal doses of VCR to Jurkat cells, and extended our observations to expression profiling of newly diagnosed patients with T-ALL. Results: We found that VCR-resistant cells over-expressed ABCC1 nearly 30-fold. The calcein AM assay confirmed that VCR-resistant cells actively extruded VCR, and that ABCC1-mediated drug resistance conferred a different spectrum of multidrug resistance than other T-ALL induction agents. siRNA experiments that blocked ABCC1 export confirmed that VCR resistance could be reversed in vitro. Analyses of T-lymphoblasts obtained from 100 newly diagnosed T-ALL patients treated on Children’s Oncology Group Phase III studies 9404 and AALL0434 that induction failure could be could be partially explained by the over-expression of ABCC1 and ABCB1. Conclusions: Taken together, these results suggest that over-expression of ABC transporters plays a contributing role in mediating treatment failure in T-ALL, and underscore the need to employ alternate treatment approaches in patients for whom induction failed or for those with relapsed disease.
基金supported by Twelfth Five-Year Mega Project of Research on The Prevention and Control of HIV/AIDS,Viral Hepatitis Infectious Diseases 2013ZX10004-217 from the Ministry of Science and Technology,People’s Republic of China,the Project Sponsored by the Young Scholar Scientific Research Foundation of China CDC(No.2013A101)General Program of State Key Laboratory for Infections Disease Prevention and Control(No.2012SKLID205)
文摘The class 1 integron and complex gene cassettes among different species of clinical isolates in northern China were characterized in this study. 383 clinical isolates were obtained from northern China, and class 1 integrons containing gene cassettes widely distributed among gram negative clinical isolates was observed. We find that the class 1 integron showed positive correlation with multidrug resistance phenotype of gram negative bacteria. In addition, we find that isolates belonged to one species harbored different types of gene cassette arrays, while same types of gene cassette arrays were observed in different species of isolates. The diversity of gene cassette arrays among the isolates indicated the complexity of multidrug resistance in clinical isolates in northern China.
文摘Objective: To analyze the molecular mechanism of integron mediated mulfi-resistanc, e in an ESBL-producing K. pneumoniae NJ 12 isolate. Methods: Susceptibility test was carried out by Kirby-Bauer method. Class Ⅰ, Ⅱ and Ⅲ integrons were detected by integrase gene PCR with primers that annealed to conserved regions of integron-encoded integrase genes intll, intl2 and intl3. The variable region of integron was amplified by integron PCR with primers that targeted the conserved flanking regions, and the product was sequenced. Six aminoglycoside modifying-enzyme genes, including ant(2")-Ⅰ, ant(3")- Ⅰ, aac(3)- Ⅰ, aac(3)-Ⅱ, aac (6')-Ⅰ, and aac(6')-Ⅱ , were detected. Results: K. pneumoniae NJ 12 was resistant to nine antibiotics, including piperacillin, ampicillin, cefuroxime, ceftazidime, cefotaxime, aztreonam, streptomycin, gentamicin and amikacin. This isolate was shown that there was positive with class Ⅰ integron, ant(2")- Ⅰ , ant(3")- Ⅰ , aac(3)-Ⅱ and aac(6')- Ⅰ modifying-enzyme genes. Neither class Ⅱ nor Ⅲ integron was detected; DNA sequencing of the fragment amplified by integron PCR revealed a novel cassette array aadR-cat-blaoxa-10/ aadA1. Conclusion: Class I integron with a novel cassette array in an ESBL-producing multidrug-resistant K. pneumon/ae NJ 12 isolate was reported from Nanjing area of China, with the GenBank accession number DQ141319.
文摘Atherosclerosis is the most common cause of cardiovascular diseases, such as myocardial infarction and stroke. The aim of this study was to investigate the effects of a novel compound ZBM30 on atherosclerosis in ApoE- deficient mice and its associated mechanism. ApoE-deficient mice (6 weeks old), fed an atherogenic high-fat and high cholesterol diet for 8 weeks, were divided into three groups. Two groups were orally administrated ZBM30 (10, 30 nag ~ kg-1) daily for 12 weeks, while the control group was administered saline. Atherosclerotic lesions with en face aortas were evaluated by Sudan IV staining, and lesion areas in aortic sinuses were evaluated by oil red O staining. Necrotic core areas and fibrous cap areas in the lesion were evaluated by henaatoxylin and eosin (HE) staining and Masson' s trichronae staining in the aorta sinuses. The effects of ZBM30 on cholesterol accumulation in naacrophages and cholesterol transporters: ATP binding cassette A1 (ABCA1) and ATP binding cassette G1 (AB- CG1) were evaluated by oil red O assay, 3H-cholesterol efflux assay, Western blot, and real-time PCR on macro- phage cell lines: Raw 264.7 and THP-1. Inanauno-fluoresces was used to determine the ABCA1 expression in naac- rophage in aorta sinuses. Luciferase reporters of wild type and mutant types of ABCA1 promoter were constructed to determine the regulatory domain of ZBM30 on ABCA1 promoter. Results showed that, compared with the control group, en face lesions in ZBM30 group ( 10, 30 mg · kg^-1 ) were reduced 54.96 ± 10.06% and 71.50 ± 15.37% respectively, and aorta sinus lesions were reduced 41.85 ± 11.21% and 82.23 ± 8.25% respectively. Necrotic core areas in the ZBM30 group were markedly reduced and fibrous cap areas were not changed. Oil red O staining and 3 H-cholesterol efflux assays on Raw 264.7 cell line revealed that ZBM30 significantly attenuated the cholesterol accumulation in naacrophages by enhancing apolipoprotein AI and HDL mediated cholesterol efflux. Furthermore, ZBM30 induced the protein and naRNA expression of cholesterol transporters such as ABCA1 and ABCG1. Inanauno- fluoresces experiment revealed that ZBM30 induced the ABCA1 expression in naacrophage in the lesion, which is consistent with the results in vitro. Luciferase reporter assay revealed that ZBM30 exerted its effect on ABCA1 via liver X receptor (LXR) binding domain. In conclusion, ZBM30 suppresses atherosclerosis through up-regulating cholesterol efflux via ABCA1 and ABCG1 transporters in ApoE-deficient mice.
基金Supported by Central Department of Microbiology,Tribhuvan University and Annapurna Neurological Institute and Allied Sciences and supported from National Research Council of Thailand 2016(R2560B064)
文摘Objective: To investigate the molecular epidemiology and antimicrobial resistance patterns of methicillin-resistant Staphylococcus aureus(MRSA) among healthcare workers and patients.Methods: MRSA isolates were recovered from nasal swabs collected at a tertiary care hospital of Nepal and confirmed on the basis of Gram staining, conventional biochemical tests, and PCR amplification of mec A gene. PCRs were also used for detection of the different resistance genes and staphylococcal cassette chromosome(SCC) mec types.Antibiotic susceptibility patterns of isolates were assessed by disc diffusion method and minimum inhibitory concentrations were determined by E-test.Results: A total of 29 MRSA were isolated from 536 nasal swabs(5.4%) of health care workers and patients at a tertiary care hospital in Nepal. All isolates were susceptible to amikacin, gentamicin, vancomycin(minimal inhibitory concentrations < 2 mg/m L), tigecycline, tetracycline, nitrofurantoin, rifampicin, quinupristin-dalfopristin, and linezolid. Among the 29 MRSA isolates, resistance to erythromycin(72%), ciprofloxacin(75%), co-trimoxazole(62%), clindamycin(10%), and chloramphenicol(10%) was found, and fifteen isolates(51%)exhibited high-level mupirocin resistance(minimal inhibitory concentrations > 1 024 mg/m L).Fourteen isolates were found harboring the mup A gene and one isolate was found carrying the novel mup B gene. High prevalence(68%) of SCCmec I type was found, followed by SCCmec V(13%) and SCCmec III(3%) among all the MRSA isolates.Conclusions: We found the emergence of SCCmec type I with high-level mupirocin resistance among MRSA in Nepal. Data also suggest that MRSA SCCmec type V strain has spread from the community to the hospital.
文摘Objective: To construct the small interfering RNA(siRNA) expression cassettes (SECs) targeting activated K-ras gene sequence and investigate the effects of SECs on K-ras gene in human pancreatic cancer cell line MIAPaCa-2. Methods: Three different sites of SECs were constructed by PCR. The K1/siRNA, K2/siRNA and K3/siRNA were located at the site 194, 491 and 327, respectively. They were transfected into MiaPaCa-2 cells by liposome to inhibit the expression of activated K-ras. In the interfering groups of site 194,491, we observed the cytopathic effect of confluent MiaPaCa-2 cells after they were incubated for 48 hours, and detected the apoptosis in cells by FACS, then we tested the alternation of K-ras gene in confluent MiaPaCa-2 cells by RT-PCR,immunofluorescence and western blot, respectively. Results: Introductions of the K1/siRNA and K2/siRNA against K-ras into MiaPaCa-2 cells led to cytopathic effect, slower proliferation and increased apoptosis, while the appearances of control MiaPaCa-2 cells remained well. The number of apoptotic cells increased compared with control cells. RT-PCR,immunofluorescence and western blot showed the effects of inhibited expression of activated K-ras gene by RNA interference in the K1/siRNA and K2/siRNA groups. We also found that the introduction of K3/siRNA had no effect on MiaPaCa-2 cells. Conclusion: K1/siRNA and K2/siRNA can inhibit the expression of activated K-ras and decrease the growth of MiaPaCa-2 cells, while K3/siRNA has no such effect, demonstrating that the suppression of tumor growth by siRNA is sequence-specific. We conclude that K-ras is involved in maintenance of tumor growth of human pancreatic cancer, and SECs against K-ras expression may be a powerful tool to be used therapeutically against human pancreatic cancer.
基金the National Basic Research and Development Program of China(973 Program, No.2007CB512000) (Sub-Project,No.2007CB512005)
文摘Objective: To study the role of nuclear factor-kappa B(NF- κB) in cholesterol efflux from THP-1 derived-foam cells treated with Angiotensin Ⅱ(Ang Ⅱ ). Methods:Cultured THP-1 derived-foam cells were treated with Ang Ⅱ or preincubated with tosyl-phenylalanine chloromethyl-ketone(TPCK) NF- κB inhibitor. The levels of activated NF- κB in the cells were examined by sandwich ELISA, Cellular cholesterol content was studied by electron microscopy scanning and zymochemistry via fluorospectrophotometer and cholesterol effiux was detected by scintillation counting technique. ABCA1 mRNA and protein were quantified by RT-PCR and Western blotting. Results:Addition of TPCK to the cells before Ang Ⅱ stimulation attenuated the response of NF- κB p65 nuclear translocation induced by Ang Ⅱ and showed no peak in foam cells group and caused a reduction in cholesterol content and an increase in cholesterol efflux by 24.1%(P〈 0.05) and 41.1%(P〈 0.05) respectively, when compared with Ang Ⅱ group. In accordance, the ABCA1 mRNA and protein were increased by 30% and 19%(P 〈 0.05) respectively, when compared with Ang Ⅱ group. Conclusion:Ang Ⅱ can downregulate ABCA1 in THP-1 derived-foam cells via NF- K B, which leads to less cholesterol effiux and the increase of cholesterol content with the consequence of the promotion of atherosclerosis.
文摘The coagulase-negative staphylococci (CoNS) have long been considered to be low pathogenicity. The possibility of a horizontal transfer of resistance and virulence genes from S. aureus to CoNS could increase the pathogenicity of these bacteria. The objective of this work is to contribute to a better knowledge of the pathogenicity of (CoNS) strains isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi/Sô-Ava. Seventy strains of CoNS isolated from surfaces and medico-technical materials of the University Hospital of Abomey-Calavi were tested for methicillin resistance. The resistance to methicillin was evaluated phenotypically by the resistance of the strains to cefoxitin and then confirmed by the search for the mecA gene using PCR. The genes encoding staphylococcal chromosomal cassette (SCCmec) types I, II and III originally found in S. aureus were tested in CoNS by multiplex PCR using specific primers. All the strains studied showed resistance to methicillin. However, only 28.5% (20/70) carried the mecA gene. SCCmec was identified in only 17.14% (12/70) of these strains. Four strains carried mecA gene as well as one of the three types of SCCmec searched. SCCmec types I, II and III were identified in CoNS strains studied. SCCmec type I was the most frequent chromosomal cassette in mecA<sup>+</sup> strains, only or in association with another SCCmec. The study also revealed methicillin-resistant strains carrying SCCmec lacking the mecA gene. Finally, 60% (12/20) of the strains were found to be non-typeable. Our results show that CoNS strains present a high resistance to methicillin and the source of this resistance in the CoNS of our study is not only the mecA gene. There is also a high diversity of SCCmec, justified by a large number of non-typeable CoNS strains. The mecA<sup>−</sup> SCCmec<sup>+</sup> methicillin-resistant strains deserve to be sequenced for further studies.
文摘Pseudomonas aeruginosa is one of the most important opportunistic human pathogens worldwide. High prevalence of Multi Drug Resistant P. aeruginosa (MDRPa) in Iran is a serious problem for antimicrobial therapy. Several studies have reported the MDRPa in Europe and Asia. Due to the use of broad-spectrum antibiotics, bacterial resistance is increasing in Iran, located in Middle East. The present cross-sectional study was designed to investigate the prevalence of class1 integron, resistance gene cassettes and antimicrobial susceptibility profiles among isolates of P. aeruginosa in Al-Zahra Hospital, Isfahan City, central part of Iran from Jan-Sep 2014. The aim of this study was to determine the antimicrobial susceptibility, the prevalence of Class1 integron, resistance gene a measuring in Iran. A total of 231 P. aeruginosa isolates were collected from clinical specimens including urine (50.6%), tracheal tube (25.5%), wound (13.4%), blood (6.1%), catheter (2.2%), cerebrospinal fluid (1.7%) and sputum (0.4%) isolates from hospitalized patients (mean age: 50.27 ± 24.12 years).The majority of patients (68%) were male. Isolates were collected from different parts of the hospital as follows: ICU, Internal Medicine, Emergency care, Pediatrics, Nephrology, Transplant Center, General surgery and Infectious. Revealed data show a high rate of MDR P. aeruginosa isolates in the studied area;also, the result signifies the spread of aadA6 among clinical isolates in hospitalized patients.
基金Supported by the National Natural Science Foundation of China(The Role of TLR4/MyD88/NF-κB Signal Transduction Pathway and Expression of miRNA-146a in Atherosclerosis and the Intervention Mechanism of Shen Invigorating Compounds,No.81202731Bushen Jiangzhi Recipe Protects Against Atherosclerosis via miR-27a-mediated PCSK9/ABCA1 Pathway,No.81873348)+2 种基金the Shanghai Natural Science Found(Inhibitory Mechanism of Chinese Herbal Compound,Shoushen Granule,for Invigorating Kidney in ApoE-/-Atherosclerosis Mouse Model by mir-19b Target Regulating ABCA1,No.16ZR1433900)the Shanghai Municipal Commission of Health and Family Planning Found(Effect of Kidney Invigoration and Lipid Intervention on the Atherosclerosis in ApoE-knockout Mice Based on mT OR signaling pathway of Autophagy System,No.201640217)Shanghai University of Traditional Chinese Medicine graduate"innovation ability training"special research projects(Mechanism of Bushen Jiangzhi Recipe Regulating TLR4/NF-κB Signaling Pathway Mediated by CD36 Through PCSK9 Targeted Regulation of apoE-/-mice Atherosclerosis,No.Y201858)
文摘OBJECTIVE: To evaluate the efficacy of Shoushen granule, prepared with four Chinese medicinals, on the targeted regulation of adenosine triphosphate binding cassette transporter A1(ABCA1) through proprotein convertase subtilisin/kexin type 9(PCSK9) and toll-like receptor 4(TLR4)/nuclear factor kappa-B(NF-κB) signaling pathway to affect atherosclerosis(AS) in ApoE-knockout(ApoE-/-) mice.METHODS: ApoE-/-mice fed with a high-fat diet were used for AS modeling and divided into Model,Shoushen, and Atorvastatin groups. C57 BL/6 J mice at the same age and background strain were included in the Control group. Western blot and immunohistochemistry were used to measure ABCA1, PCSK9, TLR4, and NF-κB protein expression in mouse aortas. Enzyme-linked immuno sorbent assay was used to measure mouse serum tumor necrosis factor-α(TNF-α), interleukin-10(IL-10), monocyte chemoattractant protein 1(MCP-1), and intercellular cell adhesion molecule-1(ICAM-1) expression. Serum lipid profiles and histopathology were also assessed. Shoushen granule were composed of Heshouwu(Radix Polygoni Multiflori) 15 g, Gouqizi(Fructus Lycii) 15 g, Sheng shanzha(Raw Fructus Crataegus Pinnatifidae) 10 g, and Sanqi(Radix Notoginseng) 3 g.RESULTS: ApoE-/-mice fed with a high-fat diet had notable AS lesions, with reduced ABCA1 and IL-10 levels, elevated PCSK9, TLR4, NF-κB, TNF-α, MCP-1,and ICAM-1 expression, and increased total cholesterol(TC) and low density lipoprotein cholesterol(LDL-C) contents. With drug interventions, the areas of AS plaques were significantly reduced,the ABCA1 and IL-10 levels were increase, while the PCSK9, TLR4, NF-κB, TC, and LDL-C contents,and the TNF-α, MCP-1, and ICAM-1 expression were reduced.CONCLUSION: Shoushen granule effectively interfered with AS development by antagonizing the expression of key factors of the PCSK9 and TLR4/NF-κB signaling pathway to upregulate ABCA1 expression.
文摘Nicotiana species of the section Alatae characteristically emit the floral scent compounds of the 'cineole cassette' comprising 1,8-cineole, limonene, myrcene, α-pinene, β-pinene, sabinene, and α-terpineol. We successfully isolated genes of Nicotiana alata and Nicotiana langsdorfii that encoded enzymes, which produced the characteristic monoter- penes of this 'cineole cassette' with α-terpineol being most abundant in the volatile spectra. The amino acid sequences of both terpineol synthases were 99% identical. The enzymes cluster in a monophyletic branch together with the closely related cineole synthase of Nicotiana suaveolens and monoterpene synthase 1 of Solanum lycopersicum. The cyclization reactions (α-terpineol to 1,8-cineole) of the terpineol synthases of N. alata and N. langsdorfii were less efficient compared to the 'cineole cassette' monoterpene synthases of Arabidopsis thaliana, N. suaveolens, Salvia fruticosa, Salvia officinalis, and Citrus unshiu. The terpineol synthases of IV. alata and N. langsdorfii were localized in pistils and in the adaxial and abaxial epidermis of the petals. The enzyme activities reached their maxima at the second day after anthesis when flowers were fully opened and the enzyme activity in N. alata was highest at the transition from day to night (diurnal rhythm).
基金supported by the National Key Project of Scientific and Technical Pillar Programs of China during the 10th Five-year Plan (Grant No 2004BA514A15-10)the 11th Five-year Plan (Grant No 2006BAK02A03-1)
文摘In this study,326 Escherichia coli isolates from food animals collected during the last four decades in China were characterized using antimicrobial susceptibility testing and screening for integrons/cassettes.Minimum inhibitory concentration(MIC) testing indicated that the antimicrobial resistance of E.coli has increased since the 1970s.The findings of this study present a warning to veterinary practitioners about the excessive use of antimicrobials,and suggest the necessity for surveillance and control of antimicrobial resistance in veterinary clinical medicine in China.
文摘P-glycoprotein(ABCB1),multidrug resistance protein-1(ABCC1)and breast cancer resistance protein(ABCG2)belong to the ATP-binding cassette(ABC)superfamily of proteins that play an important physiological role in protection of the body from toxic xenobiotics and endogenous metabolites.Beyond this,these transporters determine the toxicity profile of many drugs,and confer multidrug resistance(MDR)in cancer cells associated with a poor treatment outcome of cancer patients.It has long been hypothesized that inhibition of ABC drug efflux transporters will increase drug accumulation and thereby overcome MDR,but until now no approved inhibitor of these transporters is available in the clinic.In this review we present molecular strategies to overcome this type of drug resistance and discuss for each of these strategies their promising value or indicate underlying reasons for their limited success.
文摘Importance: The ATP-binding cassette subfamily A member 3 (ABCA3) protein plays a vital role in surfactant homeostasis. Mutations in the ABCA3 gene lead to the development of interstitial lung disease. In the most severe manifestation, mutations can lead to a fatal respiratory distress syndrome in neonates. ABCA3 belongs to the same ATP-binding cassette transporter superfamily as the cystic fibrosis transmembrane conductance regulator (CFTR), the gene that causes cystic fibrosis. Objective: To classify ABCA3 mutations in a manner similar to CFTR mutations in order to take advantage of recent advances in therapeutics. Methods: Sequence homology between the CFTR protein and the ABCA3 protein was established. The region of CFTR that is a target for the new potentiator class of drugs was of particular interest. We performed a literature search to obtain all published mutations that were thought to be disease causing. We classified these mutations using the established CFTR classification system. When possible, we drew on previous experimental classification of ABCA3 mutations. Results: Although the proteins share the same overall structure, only a 19%identity was established between CFTR and ABCA3. The CFTR therapeutic target region has a 22% homology with the corresponding ABCA3 region. Totally 233 unique protein mutations were identified. All protein mutations were classified and mapped to a schematic diagram of the ABCA3 protein. Interpretation: This new classification system for ABCA3, based on CFTR classification, will likely aid further research of clinical outcomes and identification of mutation-tailored therapeutics, with the aim for improving clinical care for patients with ABCA3 mutations.
文摘Objectives To explore the protective effect of irbesartan (lrb) under the interference with angiotensin II (Ang II) on ABCA1. Methods Electron microscopy was used to detect the morphous of foam cells. The expression of ABCA1 mRNA and its protein were determined by RT-PCR and Western blotting, respectively. The variance of cellular cholesterol content was measured by zymochemistry via-fluorospeetrophotometer. Results A positive facilitative effect of Ang II on the formation of foam cells was observed. Total cholesterol was increased significantly by Ang II, the expression of ABCA1 was down-regulated obviously by Ang II; Irb could protect ABCA1 against the lesion of Ang II; Total cellular cholesterol content was reduced significantly in Irb + Ang II group; However, considerable alteration about the cholesterol content and the expression of ABCA1 were not observed in Irb group without incubation with Ang II. Conclusions Irb could protect ABCA1 against the lesion of Ang II, which may contribute to its anti-atherosclerotic properties. ( S Chin J Cardiol 2009; 10(4) : 227 -233)
基金Supported by The Science and Technology Planning Projects of Guizhou Province and Zunyi City,No.QKHJCZK[2022]YB642,No.ZSKH·HZ(2022)344,No.gzwjkj2021-071,ZMC·YZ[2018]38,No.ZSKH·HZ[2021]58,and No.ZSKH·HZ[2021]60The General Project of Hubei Province and Jingmen City,No.2021YFYB074.
文摘BACKGROUND Patients with obstructive jaundice caused by intrahepatic bile duct stones can be effectively managed by surgery.However,some patients may develop postope-rative complications,liver failure,and other life-threatening situations.Here,we report a patient with mutations in the uridine 5’-diphospho-glucuronosyltrans-ferase 1A1(UGT1A1)and bile salt export pump(adenosine triphosphate-binding cassette subfamily B member 11,ABCB11)genes who presented multiple intrahe-patic bile duct stones and cholestasis,and the jaundice of the patient increased after partial hepatectomy.CASE SUMMARY A 52-year-old male patient admitted to the hospital on October 23,2021,with a progressive exacerbation of jaundice,was found to have multiple intrahepatic bile duct stones with the diagnoses of obstructive jaundice and acute cholecystitis.Subsequently,the patient underwent left hepatectomy with biliary exploration,stone extraction,T-tube drainage,and cholecystectomy without developing any intraoperative complications.The patient had a dark urine color with worsening jaundice postoperatively and did not respond well to plasma exchange and other symptomatic and supportive treatments.Since the progressive increase in postoperative bilirubin could not be clinically explained with any potential reason,including,if not at all,viral infection,cholangitis,autoimmune liver disease,and other causes,the patient underwent whole-exon screening for any genetic diseases,which surprisingly identified UGT1A1 and ABCB11 gene mutations related to glucuronidation of indirect bilirubin as well as bile acid transport in hepatocytes,respectively.Thus,we hypothesized that postoperative refractory cholestasis might result from UGT1A1 and ABCB11 gene mutations and further recommended liver transplantation to the patient,who eventually declined it and died from liver failure six months later.CONCLUSION Surgery may aggravate cholestasis in patients with multiple intrahepatic bile duct stones and cholestasis associated with UGT1A1 and ABCB11 gene mutations.A liver transplant may be the best option if active medical treatment fails.
基金jointly supported by the Key Research and Development Plan of Jiangsu Province,China (Grant No. BE2020318-2)the National Natural Science Foundation of China (Grant No. U19A2026)。
文摘Zinc(Zn) is an essential trace mineral that is required for plant growth and development. A number of protein transporters, which are involved in Zn uptake, translocation and distribution, are finely regulated to maintain Zn homeostasis in plant. In this study, we functionally characterized an ATP-binding cassette(ABC) transporter gene, OsPDR7, which is involved in Zn homeostasis. Os PDR7 encodes a plasma membrane-localized protein that is expressed mainly in the exodermis and xylem in the rice root.ospdr7 mutants resulted in higher Zn accumulation compared with the wild type. Heterogeneous expression of OsPDR7 in a yeast mutant rescued the Zn-deficiency phenotype, implying transport activity of OsPDR7 to Zn in yeast. However, no ZIP genes except for OsZIP9 showed change in expression profile in the ospdr7 mutants, which suggested that OsPDR7 maintains cellular Zn homeostasis through regulating Os ZIP9 expression. RNA-Seq analysis further revealed a set of differentially expressed genes between the wild type and ospdr7 mutants that allowed us to propose a possible OsPDR7-associated signaling network involving transporters, hormone responsive genes, and transcription factors. Our results revealed a novel transporter involved in the regulation of Zn homeostasis and will pave the way toward a better understanding of the fine-tuning of gene expression in the network of transporter genes.