Crosslink among cyclin-dependent kinase 9,ATP binding cassette transporter G2 and Beclin 1 in colorectal cancer

Colorectal cancer(CRC)ranks third in the number of cancers mainly because of the inability to diagnose it at an early stage.The pathogenesis of CRC is complicated,which is the result of the complex interaction of multiple genetic and environmental factors.Currently,one of the main treatments for CRC is chemotherapy.But the primary cause of CRC treatment failure is drug resistance.The expression of cyclin-dependent kinase 9(CDK9)was correlated with elevated autophagy levels in colon cancer,and high expression of CDK9 indicates a poor prognosis in CRC.The incidence of autophagy and the expressions of Beclin 1 and ATP binding cassette transporter G2 are different in left and right colon cancer,and autophagy may be involved in the occurrence of chemotherapy resistance.In this article,the roles of CDK9,ATP binding cassette transporter G2 and Beclin 1 in CRC were elucidated,emphasizing the linkages among them and providing potential therapeutic targets of CRC.

Hereditary Behavior of bar Gene Cassette is Complex in Rice Mediated by Particle Bombardment

Particle bombardment transformation using minimal gene cassette （containing the promoter, open reading frame and terminator） is the novel trend in plant genetic transformation, and its use helps to alleviate the undesirable effects of plasmid vector backbone sequences on transgenic plants. In the present article, studies related to the hereditary behavior of bar gene cassette in T1 to T3 generations of the transgenic rice （Oryza sativa L.） lines transformed by particle bombardment have been discussed. The selectable marker bar gene cassette that integrated with the rice genome had multiple copies and showed complex segregation behaviors including the presence of ‘false homozygotes’, with abnormal segregation ratios ranging from 35：1 to 144：1 （Basta-resistant： sensitive plants） in their progenies. In five out of ten original transgenic lines, bar gene can be stably transmitted as a dominant gene to self-pollinated T2 progeny. The homozygotes were obtained in three transgenic lines in T1 generation regardless of the multiple-copy integration patterns of bar gene. Southern blotting analysis showed that multiple copies of bar gene cassette were linked, which formed transgene arrays in the host rice genome. The authors also observed stable transmission of integration patterns of bar gene cassette, as obtained from Southern blotting analysis, in the regularly segregated transgenic rice lines and loss of gene in an irregularly segregated transgenic line. The segregation behavior varied among the transgenic progenies that exhibited similar Southern hybridization patterns of bar gene. On the basis of these results, the multiple-copy integration, gene lost, and gene expres- sion interaction were the major reasons for the complex segregation behaviors of bar gene cassette in transgenic rice plants.

Characterization of integrons and novel cassette arrays in bacteria from clinical isloates in China,2000-2014

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.

Transferring a Gene Expression Cassette Lacking the Vector Backbone Sequences of the 1Ax1 High Molecular Weight Glutenin Subunit into Two Chinese Hexaploid Wheat Genotypes

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.

Identification of effective siRNA against K-ras in human pancreatic cancer cell line MiaPaCa-2 by siRNA expression cassette

AIM: We shall construct the small interfering RNA (siRNA) expression cassette (SEC) targeting activated K-ras gene sequence, identify more effective siRNA sequence against K-ras gene in human pancreatic cancer cell line MiaPaCa-2 by SEC and reveal the anti-cancer effects of RNA interference (RNAi) and its therapeutic possibilities. METHODS: Three different sites of SECs were constructed by PCR. K1/siRNA,K2/siRNA and K3/siRNA are located at sites 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 sites 194 and 491, we detected the apoptosis in cells by FACS after they were incubated for 48 h, then we tested the alternation of K-ras gene in MiaPaCa-2 cells by RT-PCR immunofluorescence, respectively. RESULTS: Introduction of the Kl/siRNA and K2/siRNA against K-ras into MiaPaCa-2 cells leads to increased apoptosis, and the number of apoptotic cells is increased compared with control cells. The tests of RT-PCR immunofluorescence show the effects of inhibiting expression of activated K-ras gene by RNA interference in the Kl/siRNA and K2/siRNA groups. We also find that the introduction of K3/siRNA has no effect on MiaPaCa-2 cells. CONCLUSION: Kl/siRNA and K2/siRNA can inhibit the expression of activated K-ras but K3/siRNA has no effect, demonstrating that Kl/siRNA and K2/siRNA are effective sequences against K-ras gene and K3/siRNA are not. We conclude that specific siRNA against K-ras expression may be a powerful tool to be used therapeutically against human pancreatic cancer.

ATP-binding cassette transporters in progression and clinical outcome of pancreatic cancer: what is the way forward?

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.

ATP binding cassette C1 (ABCC1/MRP1)-mediated drug efflux contributes to disease progression in T-lineage acute lymphoblastic leukemia

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.

Class Ⅰ integron with a novel cassette array in an ESBL-producing multidrug-resistant Klebsiella pneumoniae isolate

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.

ATP-binding cassette subfamily B member 1 (ABCB1) and subfamily C member 10(ABCC1O) are not primary resistance factors for cabazitaxel

Introduction:ATP-binding cassette subfamily B member 1(ABCB1) and subfamily C member 10(ABCCIO) proteins are efflux transporters that couple the energy derived from ATP hydrolysis to the translocation of toxic substances and chemotherapeutic drugs out of cells.Cabazitaxel is a novel taxane that differs from paclitaxel by its lower affinity for ATP-binding cassette(ABC) transporters.Methods:We determined the effects of cabazitaxel,a novel tubulin-binding taxane,and paclitaxel on paclitaxelresistant,ABCB1-overexpressing KB-C2 and LLC-MDR1-WT cells and paclitaxel-resistant,ABCC10-overexpressing HEK293/ABCC10 cells by calculating the degree of drug resistance and measuring ATPase activity of the ABCB1 transporter.Results:Decreased resistance to cabazitaxel compared with paclitaxel was observed in KB-C2,LLC-MDR1-WT,and HEK293/ABCC10 cells.Moreover,cabazitaxel had low efficacy,whereas paclitaxel had high efficacy in stimulating the ATPase activity of ABCB1,indicating a direct interaction of both drugs with the transporter.Conclusion:ABCB1 and ABCC10 are not primary resistance factors for cabazitaxel compared with paclitaxel,suggesting that cabazitaxel may have a low affinity for these efflux transporters.

Characterization of Class 1 Integron Gene Cassettes among Clinical Bacteria Isolated from One Large Hospital in Northern China

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.

Coarse-Grained Free-Energy Simulations of Conformational State Transitions in an Adenosine 5′-Triphosphate-binding Cassette Exporter

ATP-binding cassette exporters transport many substrates out of cellular membranes via alternating between inward-facing and outward-facing conformations. Despite extensive research efforts over the past decades, understanding of the molecular mechanism remains elusive. As these large-scale conformational movements are global and collective, we have previously performed extensive coarse-grained molecular dynamics simulations of the potential of mean force along the conformational transition pathway [J. Phys. Chem. B 119, 1295(2015)]. However, the occluded conformational state, in which both the internal and external gate are closed, was not determined in the calculated free energy profile. In this work, we extend the above methods to the calculation of the free energy profile along the reaction coordinate, d1-d2, which are the COM distances between the two sides of the internal(d1)and the external gate(d2). The potential of mean force is thus obtained to identify the transition pathway, along which several outward-facing, inward-facing, and occluded state structures are predicted in good agreement with structural experiments. Our coarse-grained molecular dynamics free-energy simulations demonstrate that the internal gate is closed before the external gate is open during the inward-facing to outward-facing transition and vice versa during the inward-facing to outward-facing transition. Our results capture the unidirectional feature of substrate translocation via the exporter, which is functionally important in biology. This finding is different from the previous result, in which both the internal and external gates are open reported in an X-ray experiment [Proc. Natl. Acad. Sci. USA 104,19005(2007)]. Our study sheds light on the molecular mechanism of the state transitions in an ATP-binding cassette exporter.

INHIBITION OF ACTIVATED K-RAS GENE BY SIRNA EXPRESSION CASSETTES IN HUMAN PANCREATIC CARCINOMA CELL LINE MIAPACA-2

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.

Emergence of staphylococcal cassette chromosome mec type Ⅰ with high-level mupirocin resistance among methicillin-resistant Staphylococcus aureus

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.

ZBM30 suppresses atherosclerosis through up-regulating ATP-binding cassette A1 and G1

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.

Diversity and Distribution of Staphylococcal Chromosomal Cassettes Mec (SCCmec) Types I, II and III in Coagulase-Negative Staphylococcal Strains Isolated from Surfaces and Medico-Technical Materials of the University Hospital of Abomey-Calavi/Sô-Ava

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+ 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− SCCmec+ methicillin-resistant strains deserve to be sequenced for further studies.

Inhibiting NF-κB increases cholesterol efflux from THP-1 derived-foam cells treated with AngⅡ via up-regulating the expression of ATP-binding cassette transporter A1

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.

Prevalence of Class 1 Integron, Resistance Gene Cassettes and Antimicrobial Susceptibility Profiles among Isolates of Pseudomonas aeruginosa in Iran

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.

肾移植患者ABCA1及GPIHBP1水平与术后血脂的相关性

目的分析尿毒症肾移植患者三磷酸腺苷结合盒亚家族A成员1(ABCA1)及糖基磷脂酰肌醇锚定高密度脂蛋白结合蛋白1(GPIHBP1)水平与术后血脂的相关性。方法回顾性分析2015年3月至2023年1月郑州大学第一附属医院肾移植科收治的97例尿毒症肾移植患者的临床资料,按照术后血脂情况分为血脂正常组(n=34)和血脂紊乱组(n=63),比较两组患者术后1个月、3个月、6个月、12个月的ABCA1、GPIHBP1、血脂(高密度脂蛋白胆固醇、低密度脂蛋白、甘油三酯及总胆固醇)水平和他克莫司血药浓度,采用Pearson相关分析法分析术后ABCA1及GPIHBP1与血脂水平及他克莫司血药浓度的相关性,并比较两组患者随访12个月内并发症的发生情况。结果血脂紊乱组患者术后1个月、3个月、6个月、12个月的ABCA1、GPIHBP1、总胆固醇、甘油三酯、低密度脂蛋白胆固醇及他克莫司血药浓度明显高于血脂正常组,差异均有统计学意义(P<0.05);血脂紊乱组患者术后1个月、3个月、6个月及12个月的高密度脂蛋白胆固醇为(1.05±0.14)mmol/L、(1.14±0.18)mmol/L、(1.18±0.16)mmol/L、(1.23±0.17)mmol/L,均低于同时间段血脂正常组的(1.17±0.21)mmol/L、(1.37±0.28)mmol/L、(1.42±0.24)mmol/L、(1.50±0.32)mmol/L,差异均有统计学意义(P<0.05)。尿毒症肾移植患者的ABCA1与总胆固醇、他克莫司血药浓度呈正相关(P<0.05),与高密度脂蛋白胆固醇呈负相关(P<0.05),而GPIHBP1与总胆固醇、甘油三酯、他克莫司血药浓度均呈正相关(P<0.05)。血脂紊乱组患者的并发症总发生率为49.21%,明显高于血脂正常组的23.53%,差异有统计学意义(P<0.05)。结论尿毒症肾移植患者ABCA1及GPIHBP1基因水平与他克莫司血药浓度及术后血脂水平有一定相关性,检测ABCA1及GPIHBP1基因水平能够为尿毒症肾移植患者术后管理提供一定依据。

自然衰老型小鼠海马及肝脏组织中胆固醇转运相关蛋白表达的研究

目的研究自然衰老型小鼠海马及肝脏组织胆固醇转运相关蛋白表达变化,观察衰老对胆固醇转运的影响。方法选取清洁级雄性昆明小鼠1月龄10只,10月龄10只。1月龄小鼠为对照组,10月龄小鼠为老年组,饲养7 d后,采用Y字迷宫检测小鼠行为学及记忆,采用免疫组化检测肝脏脂肪酸合酶(FASN)蛋白表达变化、海马载脂蛋白E(ApoE)蛋白表达变化,采用ELISA法检测总胆固醇、三酰甘油、高密度胆固醇及低密度胆固醇含量变化,采用Western Blot法检测肝脏三磷酸腺苷结合盒转运体A1(ABCA1)、低密度脂蛋白受体(LDLR)蛋白和海马ABCA1蛋白、ApoE蛋白表达变化。结果老年组小鼠出现摄食量减少、懒动及反应较迟钝的表现。老年组小鼠的总进臂次数和交替次数少于对照组,差异有统计学意义(P<0.05)。老年组小鼠的高密度脂蛋白胆固醇含量低于对照组,三酰甘油和低密度脂蛋白胆固醇高于对照组,差异有统计学意义(P<0.05)。老年组小鼠肝脏的FASN、LDLR和ABCA1水平低于对照组,海马组织的ApoE蛋白表达高于对照组,ABCA1蛋白表达低于对照组,差异有统计学意义(P<0.05)。结论老年组小鼠外周及中枢胆固醇代谢出现异常,可能与肝脏及海马ABCA1蛋白、ApoE蛋白、LDLR蛋白表达异常有关。

THE HARDWARE & SOFTWARE DESIGN AND IMPLEMENTATION OF A NEW TYPE INTERFACE FOR THE CASSETTE TAPE RECORDER

This paper analyzes in detail the operating principle and characteristics of hardware and software of a new type interface for the cassette tape recorder,which has been developed by this author for the 8097BH target prototype machine.It discusses the design of the audio cassette tape recording format and some important aspects which must be taken care of in software for reading the cassette tape.The paper also illustrates debugging methods thoroughly.