BACKGROUND: Nerve growth factor (NGF) attenuates glutamate-induced injury to hippocampal neurons, and the human tumor suppressor gene phosphatase and tensin homologue deleted on chromosome 10 (PTEN) promotes neur...BACKGROUND: Nerve growth factor (NGF) attenuates glutamate-induced injury to hippocampal neurons, and the human tumor suppressor gene phosphatase and tensin homologue deleted on chromosome 10 (PTEN) promotes neuronal apoptosis. However, effects of PTEN in NGF-mediated neuroprotection against glutamate excitotoxicity remain poorly understood. OBJECTIVE: To investigate the relationship between NGF inhibition of glutamate-induced injury and PTEN. DESIGN, TIME AND SE'I'rlNG: The randomized, controlled, in vitro study was performed at the Department of Pathophysiology, Medical School of Nantong University, China from October 2007 to March 2008. MATERIALS: Glutamate, NGF, 4, 6-diamidino-2-phenyl-indolediacetate, 3-[4, 5-dimethylthiazol-2-yl]- 2, 5-diphenyl tetrazoliumbromide (M-I-F), and lactate dehydrogenase kit (Sigma, USA), fluorescence microscope and inverted phase contrast microscope (Olympus, Japan) were used in this study. METHODS: Hippocampal neurons were obtained from newborn (〈 24 hours) Sprague Dawley rats and cultured for 7 days. The control group was not treated with any intervention factor, the glutamate group was treated with glutamate (0.2 mmol/L), and NGF groups were treated with NGF (10, 50, 100, and 200 μg/L, respectively) prior to glutamate treatment. MAIN OUTCOME MEASURES: The MTT and lactate dehydrogenase assays were applied to evaluate viability of hippocampal neurons. Morphological changes in hippocampal neurons were observed using an inverted phase-contrast microscope, and neuronal apoptosis was detected by 4, 6-diamidino-2- phenyl-indolediacetate staining. PTEN mRNA and protein expression were measured by reverse transcription-polymerase chain reaction and Western blot analysis, respectively. RESULTS: Glutamate (0.2 mmol/L) induced significantly decreased neuronal viability and greater lactate dehydrogenase efflux compared with the control group (P 〈 0.01). However, compared with the glutamate group, cell viability significantly increased and lactate dehydrogenase efflux decreased in the NGF group with increasing NGF concentrations (P 〈 0.05 or P 〈 0.01). The apoptotic ratio and PTEN mRNA and protein expression decreased in the NGF group compared with the glutamate group (P 〈 0.01). CONCLUSION: Pretreatment with NGF exerted neuroprotective effects against glutamate-induced injury, partially through inhibition of PTEN expression and neuronal apoptosis.展开更多
AIM To evaluate the effects of phosphatase and tension homologue deleted on chromosome ten(PTEN) gene on collagen metabolism in hepatic fibrosis and the underlying mechanisms.METHODS rat primary hepatic stellate cells...AIM To evaluate the effects of phosphatase and tension homologue deleted on chromosome ten(PTEN) gene on collagen metabolism in hepatic fibrosis and the underlying mechanisms.METHODS rat primary hepatic stellate cells(HSCs) and human LX-2 cells were transfected with adenovirus containing c DNA constructs encoding wild-type PTEN(Ad-PTEN), PTEN mutant G129 E gene(Ad-G129E), and r NA interference constructs targeting the PTEN sequence PTEN short hairpin r NA to up-regulate and downregulate the expression of PTEN. HSCs were assayed using fluorescent microscopy, real-time polymerase chain reaction, and western blotting. Moreover, a CCl_4-induced rat hepatic fibrosis model was established to investigate the in vivo effects. Hematoxylin and eosin, and Masson's trichrome were used to assess the histological changes. The expression of collagen Ⅰ and Ⅲ was assessed using immunohistochemistry and western blot analysis.RESULTS Elevated expression of PTEN gene reduced serum levels of alanine transaminase and aspartate transaminase, decreased collagen deposition in the liver, and reduced hepatocyte necrosis. In contrast, knockdown of PTEN expression had an opposite effect, such as increased collagen deposition in the liver, and was molecularly characterized by the increased expression of matrix metalloproteinase(MMP)-13(P < 0.01) and MMP-2(P < 0.01), as well as decreased expression of the tissue inhibitor of metalloproteinase(TIMP)-1(P < 0.01) and TIMP-2(P < 0.01).CONCLUSION These data indicated that gene therapy using recombinant adenovirus encoding PTEN might be a novel way of treating hepatic fibrosis.展开更多
The most common digestive system(DS)cancers,including tumors of the gastrointestinal tract(GIT)such as colorectal cancer(CRC),gastric cancer(GC)and esophageal cancer(EC)as well as tumors of DS accessory organs such as...The most common digestive system(DS)cancers,including tumors of the gastrointestinal tract(GIT)such as colorectal cancer(CRC),gastric cancer(GC)and esophageal cancer(EC)as well as tumors of DS accessory organs such as pancreatic and liver cancer,are responsible for more than one-third of all cancerrelated deaths worldwide,despite the progress that has been achieved in anticancer therapy.Due to these limitations in treatment strategies,oncological research has taken outstanding steps towards a better understanding of cancer cell biological complexity and heterogeneity.These studies led to new molecular target-driven therapeutic approaches.Different in vivo and in vitro studies have revealed significant expression of B7 homologue 3(B7-H3)among the most common cancers of the GIT,including CRC,GC,and EC,whereas B7-H3 expression in normal healthy tissue of these organs was shown to be absent or minimal.This molecule is able to influence the biological behavior of GIT tumors through the various immunological and nonimmunological molecular mechanisms,and some of them are shown to be the result of B7-H3-related induction of signal transduction pathways,such as Janus kinase 2/signal transducer and activator of transcription 3,phosphatidylinositol 3-kinase/protein kinase B,extracellular signal-regulated kinase,and nuclear factor-κB.B7-H3 exerts an important role in progression,metastasis and resistance to anticancer therapy in these tumors.In addition,the results of many studies suggest that B7-H3 stimulates immune evasion in GIT tumors by suppressing antitumor immune response.Accordingly,it was observed that experimental depletion or inhibition of B7-H3 in gastrointestinal cancers improved antitumor immune response,impaired tumor progression,invasion,angiogenesis,and metastasis and decreased resistance to anticancer therapy.Finally,the high expression of B7-H3 in most common cancers of the GIT was shown to be associated with poor prognosis.In this review,we summarize the established data from different GIT cancer-related studies and suggest that the B7-H3 molecule could be a promising prognostic biomarker and therapeutic target for anticancer immunotherapy in these tumors.展开更多
Bactericidal/permeability-increasing protein (BPI) and LPS-binding protein (LBP) play an important role in host defence. Current evidence shows that BPI/LBP may be widely existed in different cells and tissue type...Bactericidal/permeability-increasing protein (BPI) and LPS-binding protein (LBP) play an important role in host defence. Current evidence shows that BPI/LBP may be widely existed in different cells and tissue types of animals. A full-length cDNA clone encoding a BPI/LBP homologue (dBPI), 1757 bp in size, was characterized in venom gland of the hundred-pace snake Deinagkistrodon acutus. Its deduced amino acid sequence of 417 residues had 13.8% - 21.5% identity to BPI like 1 (BPIL1) and BPI like 3 (BPIL3) of other animals. Conserved cysteine residues which are involved in disulfide bond formation between the final strand of the N-terminal beta sheet and the long alpha helix of BPI are identified as Cys146-Cys183 of dBPI. Phylogenetic tree analysis showed that the BPI/LBP homologues formed five large clusters and dBPI was in a large cluster including BPIL1 and BPIL3. dBPI mRNA shows a tissue specific expression in venom gland. This is the first study to identify the cDNA encoding BPI/LBP homologues from reptiles [ Current Zoology 55 (5) : 376 - 382, 2009].展开更多
In this paper, a linear relationship between the logarithm of capacity factor k and normal boiling point to of the homologues has been derived, based on the basic retention equation of liquid chromatography according ...In this paper, a linear relationship between the logarithm of capacity factor k and normal boiling point to of the homologues has been derived, based on the basic retention equation of liquid chromatography according to statistical thermodyoamics proposed by professor Ln Peizhang and others, This equation has been verified by a large number of experimental data, all the strsight lines of lnk- of bumologues for different mobile phass coaiposltion cross each other at the same point, So the intereection point equation van proposed, wbich was used to prodict the retention valu, the result was satisfactory.展开更多
Based on the intersection point rule of the retention value and normal boiling point of homologues in reversed-phase high-performance liquid chromatography(RPLC), the intersection point rule of the retention value of ...Based on the intersection point rule of the retention value and normal boiling point of homologues in reversed-phase high-performance liquid chromatography(RPLC), the intersection point rule of the retention value of homologues and mobile phase composition has been derived, and was testified by a lot of experimental data from the literature. With this newly proposed equation, we can use the retention value of the compound in one mobile phase composition to predict its retention value in any other mobile phase composition. For fourteen groups of homologues in five mobile phase compositions on five Kinds of columns, the overall average absolute error of 721 data sets is 2.8%.展开更多
Objective: Lung cancer has emerged as a leading cause of cancer death in the world. Eyes Absent (EYA) is an important and conserved transcriptional regulator of development. The aim of the present study was to iden...Objective: Lung cancer has emerged as a leading cause of cancer death in the world. Eyes Absent (EYA) is an important and conserved transcriptional regulator of development. The aim of the present study was to identify the expression of Drosophila Eyes Absent Hemologue 2 (EYA2) in non-small cell lung cancer (NSCLC) and to investigate their correlation with clinical parameters. Methods: Fresh, paired lung samples (n = 59) of NSCLC were obtained by surgical resection at the Department of Thoracic Surgery of the People's Liberation Army General Hospital. Expression of EYA2 were examined by Western blot and immunohistochemical analysis in specimens of NSCLC and paired normal lung tissue. Clinical data, pathologic result and Ki67 expression were collected and subsequent correlation with EYA2 expression was analyzed. Results: EYA2 expression was found located in cytoplasm and nucleus, but mostly in cytoplasm. The expression of EYA2 increased in NSCLC by Western blot and immunohistochemistry, which was correlated with histology type, but not correlated with gender, age, pTNM stage, histological differentiation and lymph node metastasis. Compared with normal lung tissue, the expression of EYA2 significantly was up-regulated in lung adenocarcinoma, while no significant difference in lung squamous cell carcinoma. Expression of EYA2 was uncorrelated with expression of Ki67 in NSCLC. Conclusion: Expression of EYA2 was augmented in lung adenocarcinoma. EYA2 is likely participating in tumorigenesis and development of lung adenocarcinoma as transcriptional activator.展开更多
The intersection point rule for homologues in gas chromatography was discovered many years ago,now more and more application and development are occurring in recent years~[2-6], but there are few systemic theoretical ...The intersection point rule for homologues in gas chromatography was discovered many years ago,now more and more application and development are occurring in recent years~[2-6], but there are few systemic theoretical studies.In this paper,based on the basic equation of reten- tion values in gas chromatography,we prove the intersection point rule of homologues from mathematics,study the factors affecting intersection point position,give the physical meaning of intersection point,and explain the experimental rules in references.展开更多
Background: Primordial germ cells(PGCs), the precursors of functional gametes, have distinct characteristics and exhibit several unique molecular mechanisms to maintain pluripotency and germness in comparison to so...Background: Primordial germ cells(PGCs), the precursors of functional gametes, have distinct characteristics and exhibit several unique molecular mechanisms to maintain pluripotency and germness in comparison to somatic cells. They express germ cel-specific RNA binding proteins(RBPs) by modulating tissue-specific cis-and trans-regulatory elements. Studies on gene structures of chicken vasa homologue(CVH), a chicken RNA binding protein, involved in temporal and spatial regulation are thus important not only for understanding the molecular mechanisms that regulate germ cel fate, but also for practical applications of primordial germ cells. However, very limited studies are available on regulatory elements that control germ cel-specific expression in chicken. Therefore, we investigated the intricate regulatory mechanism(s) that governs transcriptional control of CVH.Results: We constructed green fluorescence protein(GFP) or luciferase reporter vectors containing the various 5′ flanking regions of CVH gene. From the 5′ deletion and fragmented assays in chicken PGCs, we have identified a CVH promoter that locates at-316 to +275 base pair fragment with the highest luciferase activity. Additional y, we confirmed for the first time that the 5′ untranslated region(UTR) containing intron 1 is required for promoter activity of the CVH gene in chicken PGCs. Furthermore, using a transcription factor binding prediction, transcriptome analysis and siR NA-mediated knockdown,we have identified that a set of transcription factors play a role in the PGC-specific CVH gene expression.Conclusions: These results demonstrate that cis-elements and transcription factors localizing in the 5′ flanking region including the 5′ UTR and an intron are important for transcriptional regulation of the CVH gene in chicken PGCs. Final y,this information wil contribute to research studies in areas of reproductive biology, constructing of germ cel-specific synthetic promoter for tracing primordial germ cells as wel as understanding the transcriptional regulation for maintaining germness in PGCs.展开更多
This editorial examines a recent study that used radiomics based on computed tomography(CT)to predict the expression of the fibroblast-related gene enhancer of zeste homolog 2(EZH2)and its correlation with the surviva...This editorial examines a recent study that used radiomics based on computed tomography(CT)to predict the expression of the fibroblast-related gene enhancer of zeste homolog 2(EZH2)and its correlation with the survival of patients with hepatocellular carcinoma(HCC).By integrating radiomics with molecular analysis,the study presented a strategy for accurately predicting the expression of EZH2 from CT scans.The findings demonstrated a strong link between the radiomics model,EZH2 expression,and patient prognosis.This noninvasive approach provides valuable insights into the therapeutic management of HCC.展开更多
Resistance-like sequences have been amplified from first strand cDNA and genomic DNA of rice by PCR using oligonucleotide primers designed from sequence motifs conserved between resistance genes of tobacco and Arabido...Resistance-like sequences have been amplified from first strand cDNA and genomic DNA of rice by PCR using oligonucleotide primers designed from sequence motifs conserved between resistance genes of tobacco and Arabidopsis thaliana. 3 PCR clones, designated Osr1, Osr2 and Osr3 which were 98% identical in nucleotide sequence level, have been found to be significantly homologous to known plant resistance genes and all contained the conserved motifs of NBS-LRR type resistance genes, such as P-loop, kinase2a, kinase3a and transmembrane domain. Southern hybridization revealed that rice resistance gene homologues were organized as a cluster in the genome. RFLP mapping using a DH population derived from an indica/japonica cross (Zhaiyeqing 8/Jingxi 17) and an RFLP linkage map assigned two copies of Osr1 and one copy of Osr3 to the distal position of chromosome 12 where a blast resistance QTL has been mapped previously. Northern blot analysis showed that Osr1 gene was constitutively transcribed in rice leaves,展开更多
An oligosaccharide homologue named SnS-2 was isolated from the root of Scrophularia ningpoensis Hemsl. SnS-2 was purified by means of gel-permeation chromatography and ion-exchange chromatography. Its physico-chemical...An oligosaccharide homologue named SnS-2 was isolated from the root of Scrophularia ningpoensis Hemsl. SnS-2 was purified by means of gel-permeation chromatography and ion-exchange chromatography. Its physico-chemical properties, including carbohydrate content and molecular weight were determined. The structure of SnS-2 was elucidated by chemical methods along with 1H and 13C NMR spectroscopy, including two-dimensional DQCOSY and H-detected 1H, 13C HMQC experiments. These results show that SnS-2 possesses a backbone con-sisting of terminal a-Galp-(1, a-Galp-(16), a-Glcp-(16) and nonreducing end -Fruf-(2. The bioactive as-say showed that it could inhibit the growth of Lewis pulmonary carcinoma implanted in mice.展开更多
Ambient benzene homologues were measured at a site in the northeastern urban area of Beijing, China, from August 24 to September 4, 2012 by SUMMA canister sampling followed by laboratory determination using cryogenic ...Ambient benzene homologues were measured at a site in the northeastern urban area of Beijing, China, from August 24 to September 4, 2012 by SUMMA canister sampling followed by laboratory determination using cryogenic cold trap pre-concentration-GC-MS/FID, and their health risks were also assessed. Daily total benzene homologues ranged from 0.99 to 49.71 μg/m3 with an average of 11.98 μg/m3. Benzene homologues showed higher concentrations in the morning and evening than that at noontime. Comparison with previous studies revealed a trend of decrease for ambient benzene homologues probably due to the effective emission control in Beijing in recent years. Vehicular exhaust was the main source while volatilization of paints and solvents also made substantial contributions. Health risk assessment showed that BTEX (benzene, toluene, ethylbenzene, o-xylene, m-xylene and p-xylene) and styrene had no appreciable adverse non-cancer health risks for the exposed population, while benzene has potential cancer risk of 1.34E-05. Available data from cities in China all implied that benzene imposes relatively higher cancer risk on the exposed populations and therefore strict control measures should be taken to further lower ambient benzene levels in China.展开更多
Chromatograms of tocopherol homologues were obtained by a column of analytical size (inner diameter (ID) 0.46 cm cm×10 cm) packed with silica gel. Adsorption isotherms and film mass-transfer coefficient were esti...Chromatograms of tocopherol homologues were obtained by a column of analytical size (inner diameter (ID) 0.46 cm cm×10 cm) packed with silica gel. Adsorption isotherms and film mass-transfer coefficient were estimated from the chroma-tograms by using a general rate model, which considers axial dispersion, external mass-transfer and intraparticle diffusion. Based on the obtained isotherms and mass-transfer coefficient, the separation process of tocopherol homologues on simulated moving bed (SMB) was simulated using the same model. According to the simulated results, a mixture of α-, γ-, δ-tocopherols and other impurities was separated on an SMB equipment. The SMB equipment was composed of 8 columns of ID 2 cm×10 cm, with 2 columns in each section. The solid phase was silica gel, and the mobile phase was n-hexane/2-propanol (99/1 by volume). γ-and δ-tocopherols of purity greater than 98% were obtained with recovery greater than 98%. The effects of operating conditions (flow rates and switching time) on the performance of SMB were studied by both simulation and experiments. It was found that all the simulation results were quite close to the experimental results. We conclude that process development and optimization of operating conditions of SMB by simulation are feasible.展开更多
Systematic, fixed_point and long observations and sample testing make clear distributions of methane and the homologues in the low_layer air over eastern China and sea areas. Within about 250 km from epicenter of mode...Systematic, fixed_point and long observations and sample testing make clear distributions of methane and the homologues in the low_layer air over eastern China and sea areas. Within about 250 km from epicenter of moderate and strong earthquakes, oil_gas areas have methane concentration anomaly and CO\-2 anomaly in the low_layer atmosphere around the earthquakes, have a temperature increase by 1-6℃ at the occurrence of moderate and strong earthquakes and indicate that concentration anomaly of methane family in the low_layer air can be used as an important index for petroleum geochemical exploration.展开更多
This review updates the current views on aging gastric mucosa and the mechanisms of its increased susceptibility to injury. Experimental and clinical studies indicate that gastric mucosa of aging individuals-...This review updates the current views on aging gastric mucosa and the mechanisms of its increased susceptibility to injury. Experimental and clinical studies indicate that gastric mucosa of aging individuals-“aging gastropathy”-has prominent structural and functional abnormalities vs young gastric mucosa. Some of these abnormalities include a partial atrophy of gastric glands, impaired mucosal defense (reduced bicarbonate and prostaglandin generation, decreased sensory innervation), increased susceptibility to injury by a variety of damaging agents such as ethanol, aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs), impaired healing of injury and reduced therapeutic efficacy of ulcer-healing drugs. Detailed analysis of the above changes indicates that the following events occur in aging gastric mucosa: reduced mucosal blood flow and impaired oxygen delivery cause hypoxia, which leads to activation of the early growth response-1 (egr-1) transcription factor. Activation of egr-1, in turn, upregulates the dual specificity phosphatase, phosphatase and tensin homologue deleted on chromosome ten (PTEN) resulting in activation of pro-apoptotic caspase-3 and caspase-9 and reduced expression of the anti-apoptosis protein, survivin. The imbalance between pro- and anti-apoptosis mediators results in increased apoptosis and increased susceptibility to injury. This paradigm has human relevance since increased expression of PTEN and reduced expression of survivin were demonstrated in gastric mucosa of aging individuals. Other potential mechanisms operating in aging gastric mucosa include reduced telomerase activity, increase in replicative cellular senescence, and reduced expression of vascular endothelial growth factor and importin-α-a nuclear transport protein essential for transport of transcription factors to nucleus. Aging gastropathy is an important and clinically relevant issue because of: (1) an aging world population due to prolonged life span; (2) older patients have much greater risk of gastroduodenal ulcers and gastrointestinal complications (e.g., NSAIDs-induced gastric injury) than younger patients; and (3) increased susceptibility of aging gastric mucosa to injury can be potentially reduced or reversed pharmacologically.展开更多
AIM: To investigate the role of enhancer of zeste homologue 2 (EZH2) and STAT6 immunohistochemistry in the evaluation of clinical stages and prognosis of colorectal cancer (CRC). METHODS: The expression patterns were ...AIM: To investigate the role of enhancer of zeste homologue 2 (EZH2) and STAT6 immunohistochemistry in the evaluation of clinical stages and prognosis of colorectal cancer (CRC). METHODS: The expression patterns were examined by immunohistochemistry in both tumor and adjacent non-neoplastic tissues of 119 CRC patients who underwent operation during the time period from 2002 to 2004. RESULTS: The positive rates of EZH2 and STAT6 in CRC cases were 69.7% (83 of 119) and 60.5% (72 of 119), respectively, and there was signifi cant differ-ence when compared with tumor adjacent non-neoplastic tissues (P < 0.05). In all CRC cases, patientswith EZH2-positive, or STAT6-positive expression had lower survival rates than those with EZH2-negative or STAT6-negative expression (P = 0.002 and P = 0.005, respectively). Co-expression of EZH2 and STAT6 showed signifi cantly higher levels in CRC cases of high clinical TNM stages (P = 0.001), and the expression of STAT6 was also correlated with lymph node metastasis and distant metastasis (P = 0.001 and P = 0.016, respectively). Multivariate analysis revealed that EZH2 expression was an independent prognostic indicator of CRC (P = 0.039). CONCLUSION: EZH2 and STAT6 expressions have significant values in distinguishing clinical stages of CRC and predicting the prognosis of the patients.展开更多
AIM:To investigate aberrant DNA methylation of CpG islands and subsequent low-or high-level DNA microsatellite instability(MSI)which is assumed to drive colon carcinogenesis. METHODS:DNA of healthy individuals,adenoma...AIM:To investigate aberrant DNA methylation of CpG islands and subsequent low-or high-level DNA microsatellite instability(MSI)which is assumed to drive colon carcinogenesis. METHODS:DNA of healthy individuals,adenoma(tu-bular or villous/tubulovillous)patients,and colorectal carcinoma patients who underwent colonoscopy was used for assessing the prevalence of aberrant DNA methylation of human DNA mismatch repair gene mutator L homologue 1(hMLH1),Cyclin-dependent kinase inhibitor 2A(CDKN2A/p16),and O-6-methylguanine DNA methyltransferase(MGMT),as well as their rela- tion to MSI. RESULTS:The frequency of promoter methylation for each locus increased in the sequence healthy tissue/adenoma/carcinoma.MGMT showed the highest frequency in each group.MGMT and CDKN2A/p16 presented a statistically significant increase in promoter methylation between the less and more tumorigenic forms of colorectal adenomas(tubular vs tubullovillous and villous adenomas).All patients with tubulovillous/villous adenomas,as well as all colorectal cancer patients,showed promoter methylation in at least one of the examined loci.These findings suggest a potentially crucial role for methylation in the polyp/adenoma to cancer progres- sion in colorectal carcinogenesis.MSI and methylation seem to be interdependent,as simultaneous hMLH1, CDKN2A/p16,and MGMT promoter methylation was present in 8/9 colorectal cancer patients showing the MSI phenotype. CONCLUSION:Methylation analysis of hMLH1,CD- KN2A/p16,and MGMT revealed specific methylation profiles for tubular adenomas,tubulovillous/villous adenomas,and colorectal cancers,supporting the use of these alterations in assessment of colorectal tumorigenesis.展开更多
基金the Natural Science Foundation of Jiangsu Province, No. BK2004048the Social Development and Technology Plan of Nantong City, No. K2008009
文摘BACKGROUND: Nerve growth factor (NGF) attenuates glutamate-induced injury to hippocampal neurons, and the human tumor suppressor gene phosphatase and tensin homologue deleted on chromosome 10 (PTEN) promotes neuronal apoptosis. However, effects of PTEN in NGF-mediated neuroprotection against glutamate excitotoxicity remain poorly understood. OBJECTIVE: To investigate the relationship between NGF inhibition of glutamate-induced injury and PTEN. DESIGN, TIME AND SE'I'rlNG: The randomized, controlled, in vitro study was performed at the Department of Pathophysiology, Medical School of Nantong University, China from October 2007 to March 2008. MATERIALS: Glutamate, NGF, 4, 6-diamidino-2-phenyl-indolediacetate, 3-[4, 5-dimethylthiazol-2-yl]- 2, 5-diphenyl tetrazoliumbromide (M-I-F), and lactate dehydrogenase kit (Sigma, USA), fluorescence microscope and inverted phase contrast microscope (Olympus, Japan) were used in this study. METHODS: Hippocampal neurons were obtained from newborn (〈 24 hours) Sprague Dawley rats and cultured for 7 days. The control group was not treated with any intervention factor, the glutamate group was treated with glutamate (0.2 mmol/L), and NGF groups were treated with NGF (10, 50, 100, and 200 μg/L, respectively) prior to glutamate treatment. MAIN OUTCOME MEASURES: The MTT and lactate dehydrogenase assays were applied to evaluate viability of hippocampal neurons. Morphological changes in hippocampal neurons were observed using an inverted phase-contrast microscope, and neuronal apoptosis was detected by 4, 6-diamidino-2- phenyl-indolediacetate staining. PTEN mRNA and protein expression were measured by reverse transcription-polymerase chain reaction and Western blot analysis, respectively. RESULTS: Glutamate (0.2 mmol/L) induced significantly decreased neuronal viability and greater lactate dehydrogenase efflux compared with the control group (P 〈 0.01). However, compared with the glutamate group, cell viability significantly increased and lactate dehydrogenase efflux decreased in the NGF group with increasing NGF concentrations (P 〈 0.05 or P 〈 0.01). The apoptotic ratio and PTEN mRNA and protein expression decreased in the NGF group compared with the glutamate group (P 〈 0.01). CONCLUSION: Pretreatment with NGF exerted neuroprotective effects against glutamate-induced injury, partially through inhibition of PTEN expression and neuronal apoptosis.
基金Supported by the National Natural Science Foundation of China,No.30872513
文摘AIM To evaluate the effects of phosphatase and tension homologue deleted on chromosome ten(PTEN) gene on collagen metabolism in hepatic fibrosis and the underlying mechanisms.METHODS rat primary hepatic stellate cells(HSCs) and human LX-2 cells were transfected with adenovirus containing c DNA constructs encoding wild-type PTEN(Ad-PTEN), PTEN mutant G129 E gene(Ad-G129E), and r NA interference constructs targeting the PTEN sequence PTEN short hairpin r NA to up-regulate and downregulate the expression of PTEN. HSCs were assayed using fluorescent microscopy, real-time polymerase chain reaction, and western blotting. Moreover, a CCl_4-induced rat hepatic fibrosis model was established to investigate the in vivo effects. Hematoxylin and eosin, and Masson's trichrome were used to assess the histological changes. The expression of collagen Ⅰ and Ⅲ was assessed using immunohistochemistry and western blot analysis.RESULTS Elevated expression of PTEN gene reduced serum levels of alanine transaminase and aspartate transaminase, decreased collagen deposition in the liver, and reduced hepatocyte necrosis. In contrast, knockdown of PTEN expression had an opposite effect, such as increased collagen deposition in the liver, and was molecularly characterized by the increased expression of matrix metalloproteinase(MMP)-13(P < 0.01) and MMP-2(P < 0.01), as well as decreased expression of the tissue inhibitor of metalloproteinase(TIMP)-1(P < 0.01) and TIMP-2(P < 0.01).CONCLUSION These data indicated that gene therapy using recombinant adenovirus encoding PTEN might be a novel way of treating hepatic fibrosis.
文摘The most common digestive system(DS)cancers,including tumors of the gastrointestinal tract(GIT)such as colorectal cancer(CRC),gastric cancer(GC)and esophageal cancer(EC)as well as tumors of DS accessory organs such as pancreatic and liver cancer,are responsible for more than one-third of all cancerrelated deaths worldwide,despite the progress that has been achieved in anticancer therapy.Due to these limitations in treatment strategies,oncological research has taken outstanding steps towards a better understanding of cancer cell biological complexity and heterogeneity.These studies led to new molecular target-driven therapeutic approaches.Different in vivo and in vitro studies have revealed significant expression of B7 homologue 3(B7-H3)among the most common cancers of the GIT,including CRC,GC,and EC,whereas B7-H3 expression in normal healthy tissue of these organs was shown to be absent or minimal.This molecule is able to influence the biological behavior of GIT tumors through the various immunological and nonimmunological molecular mechanisms,and some of them are shown to be the result of B7-H3-related induction of signal transduction pathways,such as Janus kinase 2/signal transducer and activator of transcription 3,phosphatidylinositol 3-kinase/protein kinase B,extracellular signal-regulated kinase,and nuclear factor-κB.B7-H3 exerts an important role in progression,metastasis and resistance to anticancer therapy in these tumors.In addition,the results of many studies suggest that B7-H3 stimulates immune evasion in GIT tumors by suppressing antitumor immune response.Accordingly,it was observed that experimental depletion or inhibition of B7-H3 in gastrointestinal cancers improved antitumor immune response,impaired tumor progression,invasion,angiogenesis,and metastasis and decreased resistance to anticancer therapy.Finally,the high expression of B7-H3 in most common cancers of the GIT was shown to be associated with poor prognosis.In this review,we summarize the established data from different GIT cancer-related studies and suggest that the B7-H3 molecule could be a promising prognostic biomarker and therapeutic target for anticancer immunotherapy in these tumors.
基金funded by a grant from the local government of Zhejiang Province for the Specially Supported Discipline of Zoology
文摘Bactericidal/permeability-increasing protein (BPI) and LPS-binding protein (LBP) play an important role in host defence. Current evidence shows that BPI/LBP may be widely existed in different cells and tissue types of animals. A full-length cDNA clone encoding a BPI/LBP homologue (dBPI), 1757 bp in size, was characterized in venom gland of the hundred-pace snake Deinagkistrodon acutus. Its deduced amino acid sequence of 417 residues had 13.8% - 21.5% identity to BPI like 1 (BPIL1) and BPI like 3 (BPIL3) of other animals. Conserved cysteine residues which are involved in disulfide bond formation between the final strand of the N-terminal beta sheet and the long alpha helix of BPI are identified as Cys146-Cys183 of dBPI. Phylogenetic tree analysis showed that the BPI/LBP homologues formed five large clusters and dBPI was in a large cluster including BPIL1 and BPIL3. dBPI mRNA shows a tissue specific expression in venom gland. This is the first study to identify the cDNA encoding BPI/LBP homologues from reptiles [ Current Zoology 55 (5) : 376 - 382, 2009].
文摘In this paper, a linear relationship between the logarithm of capacity factor k and normal boiling point to of the homologues has been derived, based on the basic retention equation of liquid chromatography according to statistical thermodyoamics proposed by professor Ln Peizhang and others, This equation has been verified by a large number of experimental data, all the strsight lines of lnk- of bumologues for different mobile phass coaiposltion cross each other at the same point, So the intereection point equation van proposed, wbich was used to prodict the retention valu, the result was satisfactory.
文摘Based on the intersection point rule of the retention value and normal boiling point of homologues in reversed-phase high-performance liquid chromatography(RPLC), the intersection point rule of the retention value of homologues and mobile phase composition has been derived, and was testified by a lot of experimental data from the literature. With this newly proposed equation, we can use the retention value of the compound in one mobile phase composition to predict its retention value in any other mobile phase composition. For fourteen groups of homologues in five mobile phase compositions on five Kinds of columns, the overall average absolute error of 721 data sets is 2.8%.
文摘Objective: Lung cancer has emerged as a leading cause of cancer death in the world. Eyes Absent (EYA) is an important and conserved transcriptional regulator of development. The aim of the present study was to identify the expression of Drosophila Eyes Absent Hemologue 2 (EYA2) in non-small cell lung cancer (NSCLC) and to investigate their correlation with clinical parameters. Methods: Fresh, paired lung samples (n = 59) of NSCLC were obtained by surgical resection at the Department of Thoracic Surgery of the People's Liberation Army General Hospital. Expression of EYA2 were examined by Western blot and immunohistochemical analysis in specimens of NSCLC and paired normal lung tissue. Clinical data, pathologic result and Ki67 expression were collected and subsequent correlation with EYA2 expression was analyzed. Results: EYA2 expression was found located in cytoplasm and nucleus, but mostly in cytoplasm. The expression of EYA2 increased in NSCLC by Western blot and immunohistochemistry, which was correlated with histology type, but not correlated with gender, age, pTNM stage, histological differentiation and lymph node metastasis. Compared with normal lung tissue, the expression of EYA2 significantly was up-regulated in lung adenocarcinoma, while no significant difference in lung squamous cell carcinoma. Expression of EYA2 was uncorrelated with expression of Ki67 in NSCLC. Conclusion: Expression of EYA2 was augmented in lung adenocarcinoma. EYA2 is likely participating in tumorigenesis and development of lung adenocarcinoma as transcriptional activator.
文摘The intersection point rule for homologues in gas chromatography was discovered many years ago,now more and more application and development are occurring in recent years~[2-6], but there are few systemic theoretical studies.In this paper,based on the basic equation of reten- tion values in gas chromatography,we prove the intersection point rule of homologues from mathematics,study the factors affecting intersection point position,give the physical meaning of intersection point,and explain the experimental rules in references.
基金supported by a National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIP)(No.2015R1A3A2033826)
文摘Background: Primordial germ cells(PGCs), the precursors of functional gametes, have distinct characteristics and exhibit several unique molecular mechanisms to maintain pluripotency and germness in comparison to somatic cells. They express germ cel-specific RNA binding proteins(RBPs) by modulating tissue-specific cis-and trans-regulatory elements. Studies on gene structures of chicken vasa homologue(CVH), a chicken RNA binding protein, involved in temporal and spatial regulation are thus important not only for understanding the molecular mechanisms that regulate germ cel fate, but also for practical applications of primordial germ cells. However, very limited studies are available on regulatory elements that control germ cel-specific expression in chicken. Therefore, we investigated the intricate regulatory mechanism(s) that governs transcriptional control of CVH.Results: We constructed green fluorescence protein(GFP) or luciferase reporter vectors containing the various 5′ flanking regions of CVH gene. From the 5′ deletion and fragmented assays in chicken PGCs, we have identified a CVH promoter that locates at-316 to +275 base pair fragment with the highest luciferase activity. Additional y, we confirmed for the first time that the 5′ untranslated region(UTR) containing intron 1 is required for promoter activity of the CVH gene in chicken PGCs. Furthermore, using a transcription factor binding prediction, transcriptome analysis and siR NA-mediated knockdown,we have identified that a set of transcription factors play a role in the PGC-specific CVH gene expression.Conclusions: These results demonstrate that cis-elements and transcription factors localizing in the 5′ flanking region including the 5′ UTR and an intron are important for transcriptional regulation of the CVH gene in chicken PGCs. Final y,this information wil contribute to research studies in areas of reproductive biology, constructing of germ cel-specific synthetic promoter for tracing primordial germ cells as wel as understanding the transcriptional regulation for maintaining germness in PGCs.
文摘This editorial examines a recent study that used radiomics based on computed tomography(CT)to predict the expression of the fibroblast-related gene enhancer of zeste homolog 2(EZH2)and its correlation with the survival of patients with hepatocellular carcinoma(HCC).By integrating radiomics with molecular analysis,the study presented a strategy for accurately predicting the expression of EZH2 from CT scans.The findings demonstrated a strong link between the radiomics model,EZH2 expression,and patient prognosis.This noninvasive approach provides valuable insights into the therapeutic management of HCC.
文摘Resistance-like sequences have been amplified from first strand cDNA and genomic DNA of rice by PCR using oligonucleotide primers designed from sequence motifs conserved between resistance genes of tobacco and Arabidopsis thaliana. 3 PCR clones, designated Osr1, Osr2 and Osr3 which were 98% identical in nucleotide sequence level, have been found to be significantly homologous to known plant resistance genes and all contained the conserved motifs of NBS-LRR type resistance genes, such as P-loop, kinase2a, kinase3a and transmembrane domain. Southern hybridization revealed that rice resistance gene homologues were organized as a cluster in the genome. RFLP mapping using a DH population derived from an indica/japonica cross (Zhaiyeqing 8/Jingxi 17) and an RFLP linkage map assigned two copies of Osr1 and one copy of Osr3 to the distal position of chromosome 12 where a blast resistance QTL has been mapped previously. Northern blot analysis showed that Osr1 gene was constitutively transcribed in rice leaves,
文摘An oligosaccharide homologue named SnS-2 was isolated from the root of Scrophularia ningpoensis Hemsl. SnS-2 was purified by means of gel-permeation chromatography and ion-exchange chromatography. Its physico-chemical properties, including carbohydrate content and molecular weight were determined. The structure of SnS-2 was elucidated by chemical methods along with 1H and 13C NMR spectroscopy, including two-dimensional DQCOSY and H-detected 1H, 13C HMQC experiments. These results show that SnS-2 possesses a backbone con-sisting of terminal a-Galp-(1, a-Galp-(16), a-Glcp-(16) and nonreducing end -Fruf-(2. The bioactive as-say showed that it could inhibit the growth of Lewis pulmonary carcinoma implanted in mice.
基金supported by the Special Research Project for the National Environmental Protection Public Welfare Industry of China(No.201009032)the Strategic Pilot Science and Technology Project of Chinese Academy of Sciences(Class B)(No.XDB05010200)the Project of National Natural Science Foundation of China(No.41175111)
文摘Ambient benzene homologues were measured at a site in the northeastern urban area of Beijing, China, from August 24 to September 4, 2012 by SUMMA canister sampling followed by laboratory determination using cryogenic cold trap pre-concentration-GC-MS/FID, and their health risks were also assessed. Daily total benzene homologues ranged from 0.99 to 49.71 μg/m3 with an average of 11.98 μg/m3. Benzene homologues showed higher concentrations in the morning and evening than that at noontime. Comparison with previous studies revealed a trend of decrease for ambient benzene homologues probably due to the effective emission control in Beijing in recent years. Vehicular exhaust was the main source while volatilization of paints and solvents also made substantial contributions. Health risk assessment showed that BTEX (benzene, toluene, ethylbenzene, o-xylene, m-xylene and p-xylene) and styrene had no appreciable adverse non-cancer health risks for the exposed population, while benzene has potential cancer risk of 1.34E-05. Available data from cities in China all implied that benzene imposes relatively higher cancer risk on the exposed populations and therefore strict control measures should be taken to further lower ambient benzene levels in China.
基金Project (No. 20040335045) supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China
文摘Chromatograms of tocopherol homologues were obtained by a column of analytical size (inner diameter (ID) 0.46 cm cm×10 cm) packed with silica gel. Adsorption isotherms and film mass-transfer coefficient were estimated from the chroma-tograms by using a general rate model, which considers axial dispersion, external mass-transfer and intraparticle diffusion. Based on the obtained isotherms and mass-transfer coefficient, the separation process of tocopherol homologues on simulated moving bed (SMB) was simulated using the same model. According to the simulated results, a mixture of α-, γ-, δ-tocopherols and other impurities was separated on an SMB equipment. The SMB equipment was composed of 8 columns of ID 2 cm×10 cm, with 2 columns in each section. The solid phase was silica gel, and the mobile phase was n-hexane/2-propanol (99/1 by volume). γ-and δ-tocopherols of purity greater than 98% were obtained with recovery greater than 98%. The effects of operating conditions (flow rates and switching time) on the performance of SMB were studied by both simulation and experiments. It was found that all the simulation results were quite close to the experimental results. We conclude that process development and optimization of operating conditions of SMB by simulation are feasible.
文摘Systematic, fixed_point and long observations and sample testing make clear distributions of methane and the homologues in the low_layer air over eastern China and sea areas. Within about 250 km from epicenter of moderate and strong earthquakes, oil_gas areas have methane concentration anomaly and CO\-2 anomaly in the low_layer atmosphere around the earthquakes, have a temperature increase by 1-6℃ at the occurrence of moderate and strong earthquakes and indicate that concentration anomaly of methane family in the low_layer air can be used as an important index for petroleum geochemical exploration.
基金Supported by VA Merit Review grant to Tarnawski AS
文摘This review updates the current views on aging gastric mucosa and the mechanisms of its increased susceptibility to injury. Experimental and clinical studies indicate that gastric mucosa of aging individuals-“aging gastropathy”-has prominent structural and functional abnormalities vs young gastric mucosa. Some of these abnormalities include a partial atrophy of gastric glands, impaired mucosal defense (reduced bicarbonate and prostaglandin generation, decreased sensory innervation), increased susceptibility to injury by a variety of damaging agents such as ethanol, aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs), impaired healing of injury and reduced therapeutic efficacy of ulcer-healing drugs. Detailed analysis of the above changes indicates that the following events occur in aging gastric mucosa: reduced mucosal blood flow and impaired oxygen delivery cause hypoxia, which leads to activation of the early growth response-1 (egr-1) transcription factor. Activation of egr-1, in turn, upregulates the dual specificity phosphatase, phosphatase and tensin homologue deleted on chromosome ten (PTEN) resulting in activation of pro-apoptotic caspase-3 and caspase-9 and reduced expression of the anti-apoptosis protein, survivin. The imbalance between pro- and anti-apoptosis mediators results in increased apoptosis and increased susceptibility to injury. This paradigm has human relevance since increased expression of PTEN and reduced expression of survivin were demonstrated in gastric mucosa of aging individuals. Other potential mechanisms operating in aging gastric mucosa include reduced telomerase activity, increase in replicative cellular senescence, and reduced expression of vascular endothelial growth factor and importin-α-a nuclear transport protein essential for transport of transcription factors to nucleus. Aging gastropathy is an important and clinically relevant issue because of: (1) an aging world population due to prolonged life span; (2) older patients have much greater risk of gastroduodenal ulcers and gastrointestinal complications (e.g., NSAIDs-induced gastric injury) than younger patients; and (3) increased susceptibility of aging gastric mucosa to injury can be potentially reduced or reversed pharmacologically.
基金Supported by National High-Tech Research and Development Program of China (863 Program), No. 2006AA02A402
文摘AIM: To investigate the role of enhancer of zeste homologue 2 (EZH2) and STAT6 immunohistochemistry in the evaluation of clinical stages and prognosis of colorectal cancer (CRC). METHODS: The expression patterns were examined by immunohistochemistry in both tumor and adjacent non-neoplastic tissues of 119 CRC patients who underwent operation during the time period from 2002 to 2004. RESULTS: The positive rates of EZH2 and STAT6 in CRC cases were 69.7% (83 of 119) and 60.5% (72 of 119), respectively, and there was signifi cant differ-ence when compared with tumor adjacent non-neoplastic tissues (P < 0.05). In all CRC cases, patientswith EZH2-positive, or STAT6-positive expression had lower survival rates than those with EZH2-negative or STAT6-negative expression (P = 0.002 and P = 0.005, respectively). Co-expression of EZH2 and STAT6 showed signifi cantly higher levels in CRC cases of high clinical TNM stages (P = 0.001), and the expression of STAT6 was also correlated with lymph node metastasis and distant metastasis (P = 0.001 and P = 0.016, respectively). Multivariate analysis revealed that EZH2 expression was an independent prognostic indicator of CRC (P = 0.039). CONCLUSION: EZH2 and STAT6 expressions have significant values in distinguishing clinical stages of CRC and predicting the prognosis of the patients.
基金Supported by A 2-year grant of the Greek Ministry of Health and Welfare,No.111K/56
文摘AIM:To investigate aberrant DNA methylation of CpG islands and subsequent low-or high-level DNA microsatellite instability(MSI)which is assumed to drive colon carcinogenesis. METHODS:DNA of healthy individuals,adenoma(tu-bular or villous/tubulovillous)patients,and colorectal carcinoma patients who underwent colonoscopy was used for assessing the prevalence of aberrant DNA methylation of human DNA mismatch repair gene mutator L homologue 1(hMLH1),Cyclin-dependent kinase inhibitor 2A(CDKN2A/p16),and O-6-methylguanine DNA methyltransferase(MGMT),as well as their rela- tion to MSI. RESULTS:The frequency of promoter methylation for each locus increased in the sequence healthy tissue/adenoma/carcinoma.MGMT showed the highest frequency in each group.MGMT and CDKN2A/p16 presented a statistically significant increase in promoter methylation between the less and more tumorigenic forms of colorectal adenomas(tubular vs tubullovillous and villous adenomas).All patients with tubulovillous/villous adenomas,as well as all colorectal cancer patients,showed promoter methylation in at least one of the examined loci.These findings suggest a potentially crucial role for methylation in the polyp/adenoma to cancer progres- sion in colorectal carcinogenesis.MSI and methylation seem to be interdependent,as simultaneous hMLH1, CDKN2A/p16,and MGMT promoter methylation was present in 8/9 colorectal cancer patients showing the MSI phenotype. CONCLUSION:Methylation analysis of hMLH1,CD- KN2A/p16,and MGMT revealed specific methylation profiles for tubular adenomas,tubulovillous/villous adenomas,and colorectal cancers,supporting the use of these alterations in assessment of colorectal tumorigenesis.