The fresh water unicellular green alga Chlamydomonas reinhardtii was used to explore whether it could function as a model system to identify proteins that are differentially expressed in response to arsenate exposure....The fresh water unicellular green alga Chlamydomonas reinhardtii was used to explore whether it could function as a model system to identify proteins that are differentially expressed in response to arsenate exposure. Cells were treated with different concentrations of arsenate ranging from 100 - 400 μM. When exposed to 200 μM arsenate, the amount of live cells started to lessen on the second day and continued to diminish, indicating a toxic effect of arsenate. Proteomic analysis was used to investigate if these cells showed a specific response to arsenic-induced stress. Fifteen proteins were found that were over-expressed in the 200 μM arsenate-treated samples and two proteins were found to be very strongly over-expressed in samples treated with 400 μM. These were selected for identification using liquid chromatography coupled with tandem mass spectrometry. Oxidative stress and protein damage were the major effects as shown by the up-regulation of Mn-superoxide dismutase, an oxygen-evolving enhancer protein, a chaperonin-like protein and a heat shock protein.展开更多
Among infertile men, a diagnosis of unilateral varicocele is made in 90% of varicocele cases and bilateral in the remaining varicocele cases. However, there are reports of under-diagnosis of bilateral varicocele among...Among infertile men, a diagnosis of unilateral varicocele is made in 90% of varicocele cases and bilateral in the remaining varicocele cases. However, there are reports of under-diagnosis of bilateral varicocele among infertile men and that its prevalence is greater than 10%. In this prospective study, we aimed to examine the differentially expressed proteins （DEP） extracted from spermatozoa cells of patients with bilateral varicocele and fertile donors. Subjects consisted of 17 men diagnosed with bilateral varicocele and 10 proven fertile men as healthy controls. Using the LTQ-orbitrap elite hybrid mass spectrometry system, proteomic analysis was done on pooled samples from 3 patients with bilateral varicocele and 5 fertile men. From these samples, 73 DEP were identified of which 58 proteins were differentially expressed, with 7 proteins unique to the bilateral varicocele group and 8 proteins to the fertile control group. Majority of the DEPs were observed to be associated with metabolic processes, stress responses, oxidoreductase activity, enzyme regulation, and immune system processes. Seven DEP were involved in sperm function such as capacitation, motility, and sperm-zona binding. Proteins TEKT3 and TCP11 were validated by Western blot analysis and may serve as potential biomarkers for bilateral varicocele. In this study, we have demonstrated for the first time the presence of DEP and identified proteins with distinct reproductive functions which are altered in infertile men with bilateral varicocele. Functional proteomic profiling provides insight into the mechanistic implications of bilateral varicocele-associated male infertility.展开更多
Background:Determining the etiology of biliary strictures is challenging,and the sensitivities of the current tests to diagnose them are low.Protein biomarkers in bile,in combination with other tests,may improve sensi...Background:Determining the etiology of biliary strictures is challenging,and the sensitivities of the current tests to diagnose them are low.Protein biomarkers in bile,in combination with other tests,may improve sensitivity in diagnosing biliary strictures.Objective:To analyse the differential abundance of proteins in benign and malignant biliary strictures through proteomic analysis of bile.Methods:In this prospective,cross-sectional study,bile was aspirated in 24 patients undergoing endoscopic retrograde cholangiopancreatography(ERCP)including six patients with primary sclerosing cholangitis(PSC),three with cholangiocarcinoma(CCA),ten with pancreatic cancer,and five with benign biliary conditions.Liquid chromatography/mass spectrometry was used to examine the bile for differential abundance of protein biomarkers.The relative abundance of various proteins was compared in the malignant vs.benign groups and in CCA vs.PSC.Results:The majority of the proteins identified in bile were similar to those of the plasma(plasma proteins)and certain proteins were differentially expressed among the different groups(CCA,pancreatic cancer,PSC or benign).A total of 18 proteins were identified as being more abundant in the malignant group(CCA and pancreatic cancer)than in the benign strictures group,including myeloperoxidase,complement C3,inter-alpha-trypsin inhibitor heavy chain H4,apolipoprotein B-100,and kininogen-1 isoform 2.A total of 30 proteins were identified to be less abundant in the malignant group than in the benign group,including trefoil factor 2,superoxide dismutase[Cu-Zn],kallikrein-1,carboxypeptidase B and trefoil factor 1.Conclusions:Protein biomarkers in bile may differentiate malignant from benign biliary strictures.Larger studies are warranted to validate these observations.展开更多
文摘The fresh water unicellular green alga Chlamydomonas reinhardtii was used to explore whether it could function as a model system to identify proteins that are differentially expressed in response to arsenate exposure. Cells were treated with different concentrations of arsenate ranging from 100 - 400 μM. When exposed to 200 μM arsenate, the amount of live cells started to lessen on the second day and continued to diminish, indicating a toxic effect of arsenate. Proteomic analysis was used to investigate if these cells showed a specific response to arsenic-induced stress. Fifteen proteins were found that were over-expressed in the 200 μM arsenate-treated samples and two proteins were found to be very strongly over-expressed in samples treated with 400 μM. These were selected for identification using liquid chromatography coupled with tandem mass spectrometry. Oxidative stress and protein damage were the major effects as shown by the up-regulation of Mn-superoxide dismutase, an oxygen-evolving enhancer protein, a chaperonin-like protein and a heat shock protein.
文摘Among infertile men, a diagnosis of unilateral varicocele is made in 90% of varicocele cases and bilateral in the remaining varicocele cases. However, there are reports of under-diagnosis of bilateral varicocele among infertile men and that its prevalence is greater than 10%. In this prospective study, we aimed to examine the differentially expressed proteins （DEP） extracted from spermatozoa cells of patients with bilateral varicocele and fertile donors. Subjects consisted of 17 men diagnosed with bilateral varicocele and 10 proven fertile men as healthy controls. Using the LTQ-orbitrap elite hybrid mass spectrometry system, proteomic analysis was done on pooled samples from 3 patients with bilateral varicocele and 5 fertile men. From these samples, 73 DEP were identified of which 58 proteins were differentially expressed, with 7 proteins unique to the bilateral varicocele group and 8 proteins to the fertile control group. Majority of the DEPs were observed to be associated with metabolic processes, stress responses, oxidoreductase activity, enzyme regulation, and immune system processes. Seven DEP were involved in sperm function such as capacitation, motility, and sperm-zona binding. Proteins TEKT3 and TCP11 were validated by Western blot analysis and may serve as potential biomarkers for bilateral varicocele. In this study, we have demonstrated for the first time the presence of DEP and identified proteins with distinct reproductive functions which are altered in infertile men with bilateral varicocele. Functional proteomic profiling provides insight into the mechanistic implications of bilateral varicocele-associated male infertility.
基金supported by a research grant from the American College of Gastroenterology(ACG)(to U.N)in part by the National Institutes of Health,National Center for Research Resources,CTSA,UL1TR 000439-06 Cleveland,OhioObitrap Elite Instrument was purchased from an NIH S10 shared instrument grant(1S10RR031537-01).
文摘Background:Determining the etiology of biliary strictures is challenging,and the sensitivities of the current tests to diagnose them are low.Protein biomarkers in bile,in combination with other tests,may improve sensitivity in diagnosing biliary strictures.Objective:To analyse the differential abundance of proteins in benign and malignant biliary strictures through proteomic analysis of bile.Methods:In this prospective,cross-sectional study,bile was aspirated in 24 patients undergoing endoscopic retrograde cholangiopancreatography(ERCP)including six patients with primary sclerosing cholangitis(PSC),three with cholangiocarcinoma(CCA),ten with pancreatic cancer,and five with benign biliary conditions.Liquid chromatography/mass spectrometry was used to examine the bile for differential abundance of protein biomarkers.The relative abundance of various proteins was compared in the malignant vs.benign groups and in CCA vs.PSC.Results:The majority of the proteins identified in bile were similar to those of the plasma(plasma proteins)and certain proteins were differentially expressed among the different groups(CCA,pancreatic cancer,PSC or benign).A total of 18 proteins were identified as being more abundant in the malignant group(CCA and pancreatic cancer)than in the benign strictures group,including myeloperoxidase,complement C3,inter-alpha-trypsin inhibitor heavy chain H4,apolipoprotein B-100,and kininogen-1 isoform 2.A total of 30 proteins were identified to be less abundant in the malignant group than in the benign group,including trefoil factor 2,superoxide dismutase[Cu-Zn],kallikrein-1,carboxypeptidase B and trefoil factor 1.Conclusions:Protein biomarkers in bile may differentiate malignant from benign biliary strictures.Larger studies are warranted to validate these observations.
