Hyperhomocysteinemia and abnormal blood lipids are independent risk factors for stroke. However, whether both factors exert a synergistic effect in the onset of stroke remains unclear. The present study is a retrospec...Hyperhomocysteinemia and abnormal blood lipids are independent risk factors for stroke. However, whether both factors exert a synergistic effect in the onset of stroke remains unclear. The present study is a retrospective analysJs of 2 089 cases of stroke and 2 089 control cases of simple in- tervertebral disk protrusion using a paired multivariate logistic regression method. Adjusting for known confounding variables including the patients' age, gender, smoking status, alcohol con- sumption status, patient and family medical history, and clinical biochemical indices, elevated ho- mocysteine level was related to the onset of stroke. Patients with elevated homocysteJne levels and abnormal blood lipids showed a 40.9 % increase in the risk for stroke compared to patients with normal homocysteine levels and blood lipids (odds ratio 1.409; 95% confidence interval 1.127-1.761). These results indicate that elevated homocysteine and abnormal blood lipids exert synergistic effects in the onset of stroke. Patients with elevated homocysteine levels and abnormal blood lipids are predisposed to stroke.展开更多
AIM:To investigate the potential role of oxidative stress and the possible therapeutic effects of N-acetyl cysteine(NAC),amifostine(AMF)and ascorbic acid(ASC)in methotrexate(MTX)-induced hepatotoxicity.METHODS:An MTX-...AIM:To investigate the potential role of oxidative stress and the possible therapeutic effects of N-acetyl cysteine(NAC),amifostine(AMF)and ascorbic acid(ASC)in methotrexate(MTX)-induced hepatotoxicity.METHODS:An MTX-induced hepatotoxicity model was established in 44 male Sprague Dawley rats by administration of a single intraperitoneal injection of20 mg/kg MTX.Eleven of the rats were left untreated(Model group;n=11),and the remaining rats were treated with a 7-d course of 50 mg/kg per day NAC (MTX+NAC group;n=11),50 mg/kg per single dose AMF(MTX+AMF group;n=11),or 10 mg/kg per day ASC(MTX+ASC group;n=11).Eleven rats that received no MTX and no treatments served as the negative control group.Structural and functional changes related to MTX-and the various treatments were assessed by histopathological analysis of liver tissues and biochemical assays of malondialdehyde(MDA),superoxide dismutase(SOD),catalase,glutathione(GSH)and xanthine oxidase activities and of serum levels of aspartate aminotransferase,alanine aminotransferase,alkaline phosphatase and total bilirubin.RESULTS:Exposure to MTX caused structural and functional hepatotoxicity,as evidenced by significantly worse histopathological scores[median(range)injury score:control group:1(0-3)vs 7(6-9),P=0.001]and significantly higher MDA activity[409(352-466)nmol/g vs 455.5(419-516)nmol/g,P<0.05].The extent of MTX-induced perturbation of both parameters was reduced by all three cytoprotective agents,but only the reduction in hepatotoxicity scores reached statistical significance[4(3-6)for NAC,4.5(3-5)for AMF and 6(5-6)for ASC;P=0.001,P=0.001 and P<0.005vs model group respectively].Exposure to MTX also caused a significant reduction in the activities of GSH and SOD antioxidants in liver tissues[control group:3.02(2.85-3.43)μmol/g and 71.78(61.88-97.81)U/g vs model group:2.52(2.07-3.34)μmol/g and 61.46(58.27-67.75)U/g,P<0.05];however,only the NAC treatment provided significant increases in these antioxidant enzyme activities[3.22(2.54-3.62)μmol/g and 69.22(61.13-100.88)U/g,P<0.05 and P<0.01vs model group respectively].CONCLUSION:MTX-induced structural and functional damage to hepatic tissues in rats may involve oxidative stress,and cytoprotective agents(NAC>AMF>ASC)may alleviate MTX hepatotoxicity.展开更多
Triangular silver nanoprisms were prepared and applied to make colorimetric detection of cysteine based on our findings that cysteine could lead to the blue shift of the dipole plasmon resonance absorption, but other ...Triangular silver nanoprisms were prepared and applied to make colorimetric detection of cysteine based on our findings that cysteine could lead to the blue shift of the dipole plasmon resonance absorption, but other 19 kinds of natural amino acids could not. Cysteine with a concentration 160 nmol/L can result in a color change that can be discerned with naked eyes.展开更多
BACKGROUND Aberrant methylation in DNA regulatory regions could downregulate tumor suppressor genes without changing the sequences.However,our knowledge of secreted protein acidic and rich in cysteine(SPARC)and its ab...BACKGROUND Aberrant methylation in DNA regulatory regions could downregulate tumor suppressor genes without changing the sequences.However,our knowledge of secreted protein acidic and rich in cysteine(SPARC)and its aberrant methylation in gastric cancer(GC)is still inadequate.In the present research,we performed fundamental research to clarify the precise function of methylation on SPARC and its significance in GC.AIM To investigate promoter methylation and the effects of the SPARC gene in GC cells and tissues and to evaluate its clinical significance.METHODS Plasmids that overexpressed the SPARC gene were transfected into human GC BGC-823 cells;non-transfected cells were used as a control group(NC group).Quantitative real-time polymerase chain reaction and western blotting(WB)were then used to detect the expression of SPARC.Methylation-specific polymerase chain reaction was executed to analyze the gene promoter methylation status.Cell viability was measured by the cell counting kit-8 assay.The migration and invasion ability of cells were detected by scratch assays and transwell chamber assays,respectively.Cell cycle events and apoptosis were observed with a flow cytometer.RESULTS The expression of SPARC mRNA in GC tissues and cells was significantly lower and showed differing degrees of hypermethylation,respectively,than that in normal adjacent tissues and control cells.Treatment with 5-Aza-2’-deoxycytidine(5-Aza-Cdr)was able to restore the expression of SPARC and reverse promoter hypermethylation.Overexpression of the SPARC gene significantly inhibited proliferation,migration,and invasion of GC cells,while also causing cell cycle arrest and apoptosis;the NC group exhibited the opposite effects.CONCLUSION This study demonstrated that SPARC could function as a tumor suppressor and might be silenced by promoter hypermethylation.Furthermore,in GC cells,SPARC inhibited migration,invasion,and proliferation,caused cell cycle arrest at the G0/G1 phase,and promoted apoptosis.展开更多
In this work,a kind of stabilized ferrofluid based on magnetite nanoparticles(mean core and its coating size about 21.9 and 1.6 nm,respectively)was synthesized via coprecipitation method.Cysteine was used as surfactan...In this work,a kind of stabilized ferrofluid based on magnetite nanoparticles(mean core and its coating size about 21.9 and 1.6 nm,respectively)was synthesized via coprecipitation method.Cysteine was used as surfactant due to its proper conjunction to the surface of magnetite nanoparticles.Coating density and synthesized ferrofluids were characterized by using transmission electron microscope,thermogravimetry analysis,dynamic light scattering and fourier transform infrared spectroscopy techniques.Magnetic resonance imaging studies show that the synthesized ferrofluid can be used as a potential contrast enhancement agent especially for imaging lymphatic system.展开更多
A sensitive and selective chemiluminescence (CL) method was developed for the determination of cysteine. This method is based on that the weak CL of cysteine oxidized with cerium (IV) can be greatly enhanced by quinin...A sensitive and selective chemiluminescence (CL) method was developed for the determination of cysteine. This method is based on that the weak CL of cysteine oxidized with cerium (IV) can be greatly enhanced by quinine, and the total cysteine in human serum can be detected through simply diluting with water, showing a simpler analytical characteristic.展开更多
A simple flow injection spectrophotometric method is reported for the determination of cysteine,N-acetyl cysteine and glutathione based on the reduction of Fe(Ⅲ)/ferricyanide,the in situ reduced ions are reacted wi...A simple flow injection spectrophotometric method is reported for the determination of cysteine,N-acetyl cysteine and glutathione based on the reduction of Fe(Ⅲ)/ferricyanide,the in situ reduced ions are reacted with unreduced portion of ferricyanide/Fe(Ⅲ) to form soluble Prussian blue,which is monitored at 735 nm.The calibration graphs are linear in the concentration ranges of(1―100)×10-6 mol/L for cysteine and N-acetyl cysteine,and(1―50)×10-6 mol/L for glutathione.The relative standard deviations of 1.8%,2.5% and 1.9% were found for eleven replicate analyses of 5×10-6 mol/L cysteine,N-acetyl cysteine and glutathione.The limits of detection(3σ blank) at 5×10-7 mol/L for cysteine,and 3×10-7 mol/L for N-acetyl cysteine and glutathione were obtained.The proposed method allowed 60 injections/h.The effects of common substances present in pharmaceuticals and human physiological fluids were examined.The method was applied to determining cysteine in pharmaceutical formulations with the recoveries in a range of 97% to 106% and the results obtained are agreed well with labeled values.展开更多
A fluorescence ratiometric probe 1 for cysteine (Cys) and homocysteine (Hcy) has been rationally constructed based on intramolecular charge transfer (ICT) mechanism. Upon treatment with Cys/Hcy, probe 1 exhibited a fl...A fluorescence ratiometric probe 1 for cysteine (Cys) and homocysteine (Hcy) has been rationally constructed based on intramolecular charge transfer (ICT) mechanism. Upon treatment with Cys/Hcy, probe 1 exhibited a fluorescence ratiometric response, with the emission wavelength displaying a large shift (from 526 nm to 446 nm). When 90 μM Cys were added, the emission ratios (I446/I526) of the probe changed dramatically from 0.01797 to 4.65472. The detection limit was also measured to be 0.18 μM (S/N = 3). The theoretical calculations have confirmed that the ratiometric response of probe 1 to Cys/Hcy is due to the inhibition of ICT process upon the reaction of probe 1 with Cys/Hcy. Furthermore, the fluorescence imaging experiments in living cell demonstrated that probe 1 was favourable for intracellular Cys/Hcy imaging.展开更多
Optimal dietary methionine (Met) to lysine (Lys) ratio in presence of elevated dietary cysteine (Cys) levels was derived for meat type growing chicken. Twelve averaged weighed Ross 308 birds (each 50% of male and fema...Optimal dietary methionine (Met) to lysine (Lys) ratio in presence of elevated dietary cysteine (Cys) levels was derived for meat type growing chicken. Twelve averaged weighed Ross 308 birds (each 50% of male and female per dietary treatment) were utilized in N balance trials. During starter (d10 - 20) and grower period (d25 - 35) five dietary treatments were used. Diets based on uniform mixtures of maize, wheat, soybean meal, potato protein and fish meal were supplemented with crystalline amino acids (AA). In diets 1 - 3, the dietary Cys to Met ratio was set as 85, 95 and 105 to 100, respectively. Diet 4, at a Cys to Met ratio of 105 to 100, was additionally supplemented with betaine (BET) as methyl group donor. Diets 1 - 4 were limiting in Met, diet 5 without L-Lys·HCl addition was limiting in Lys. Individual N-balance data per treatment were utilized for assessing protein quality and efficiency of dietary Met (Diets 1 - 4) or Lys (Diet 5) based on “Goettingen approach”. Elevated dietary Cys supply and supplemented BET failed to improve both dietary protein quality and Met efficiency. The established optimal Met to Lys ratio was on average 34 to 100 for growing chicken during starter and grower period, respectively.展开更多
Cardiac and renal diseases(CRDs) are characterized by extensive remodeling of the extracellular matrix(ECM)architecture of the cardiorenal system. Among the many extracellular proteolytic enzymes present in cardiorena...Cardiac and renal diseases(CRDs) are characterized by extensive remodeling of the extracellular matrix(ECM)architecture of the cardiorenal system. Among the many extracellular proteolytic enzymes present in cardiorenal cells and involved in ECM remodeling, members of the matrix metalloproteinase family and serine protease family have received the most attention. However, recent findings from laboratory and clinical studies have indicated that cysteine protease cathepsins also participate in pathogenesis of the heart and kidney.Deficiency and pharmacological inhibition of cathepsins have allowed their in vivo evaluation in the setting of pathological conditions. Furthermore, recent studiesevaluating the feasibility of cathepsins as a diagnostic tool have suggested that the serum levels of cathepsins L, S and K and their endogenous inhibitor cystatin C have predictive value as biomarkers in patients with coronary artery disease and heart and renal failure. The goal of this review is to highlight recent discoveries regarding the contributions of cathepsins in CRDs, particularly hypertensive heart failure and proteinuric kidney disease.展开更多
Rat protein DE is an androgen-dependent cysteine-rich secretory protein (CRISP) synthesized by proximal epididymal regions. DE, also known as CRISP-1, is localized on the equatorial segment of acrosome-reacted sperm...Rat protein DE is an androgen-dependent cysteine-rich secretory protein (CRISP) synthesized by proximal epididymal regions. DE, also known as CRISP-1, is localized on the equatorial segment of acrosome-reacted spermatozoa and participates in gamete fusion through binding to egg complementary sites. Immunization of rats with DE inhibits fertility and sperm fusion ability, suggesting that DE represents a good epididymal contraceptive target. Recombinant DE fragments and synthetic peptides revealed that DE binds to the egg via a 12-amino acid region of an evolutionarily conserved motif, Signature 2 (S2). The ability of other CRISP to bind to the rat egg was correlated with their S2 amino acid sequences. Although testicular protein Tpx- 1 (CRISP-2) was capable of binding to rodent eggs, human epididymal AEG-related protein (ARP) and helothermine (from lizard saliva) were not. The S2 region presented only two substitutions in Tpx-1 and four in ARP and helothermine, compared with the DE S2, suggesting that this amino acid sequence was relevant for egg interaction. Studies with Tpx- 1 and anti-Tpx- 1 revealed the participation of this protein in gamete fusion through binding to complementary sites in the egg. In competition studies, DE reduced binding of Tpx- 1 dose-dependently, indicating that both CRISP share the egg complementary sites. That anti-DE and anti-Tpx-1 inhibit sperm-egg fusion while recognizing only the corresponding proteins, suggests functional cooperation between these homologous CRISP to ensure fertilization success. These results increase our understanding of the molecular mechanisms of gamete fusion and contribute to the development of new and safer fertility regulating methods. (Asian J Androl 2007 July; 9: 528-532)展开更多
Cryopreservation is associated with the production of reactive oxygen species, which leads to lipid peroxidation of the sperm membrane and consequently a reduction in sperm motility and decreased fertility potential. ...Cryopreservation is associated with the production of reactive oxygen species, which leads to lipid peroxidation of the sperm membrane and consequently a reduction in sperm motility and decreased fertility potential. The aim of this study was to determine the optimal concentration of L-cysteine needed for cryopreservation of boar semen. Twelve boars provided semen of proven motility and morphology for this study. The semen was divided into four portions in which the lactose-egg yolk (LEY) extender used to resuspend the centrifuged sperm pellet was supplemented with various concentrations of L-cysteine to reach 0 mmol L^-1 (group Ⅰ, control), 5 mmol L^-1 (group Ⅱ), 10 mmol L^-1 (group Ⅲ) and 15 mmol L^-1 (group Ⅳ). Semen suspensions were loaded in straws (0.5 mL) and placed in a controlled-rate freezer. After cryopreservation, frozen semen samples were thawed and investigated for progressive motility, viability using SYBR-14/EthD-1 staining and acrosome integrity using FITC-PNA/EthD-1 staining. There was a significantly higher (P 〈 0.01) percentage of progressive motility, viability and acrosomal integrity in two L-cysteine-supplemented groups (group Ⅱ and group Ⅲ) compared with the control. There was a biphasic effect of L-cysteine, with the highest percentage of progressive motility, viability and acrosomal integrity in group Ⅲ. In conclusion, 5 or 10 mmol L^-1 was the optimum concentration of L-cysteine to be added to the LEY extender for improving the quality of frozen-thawed boar semen.展开更多
Cysteine-rich secretory protein-1 (CRISP-1) is a glycoprotein secreted by the epididymal epithelium. It is a member of a large family of proteins characterized by two conserved domains and a set of 16 conserved cyst...Cysteine-rich secretory protein-1 (CRISP-1) is a glycoprotein secreted by the epididymal epithelium. It is a member of a large family of proteins characterized by two conserved domains and a set of 16 conserved cysteine residues. In mammals, CRISP-1 inhibits sperm-egg fusion and can suppress sperm capacitation. The molecular mechanism of action of the mammalian CRISP proteins remains unknown, but certain non-mammalian CRISP proteins can block ion channels. In the rat, CRISP-1 comprises two forms referred to as Proteins D and E. Recent work in our laboratory demonstrates that the D form of CRISP-1 associates transiently with the sperm surface, whereas the E form binds tightly. When the spermatozoa are washed, the E form of CRISP-1 persists on the sperm surface after all D form has dissociated. Cross-linking studies demonstrate different protein-protein interaction patterns for D and E, although no binding partners for either protein have yet been identified. Mass spectrometric analyses revealed a potential post-translational modification on the E form that is not present on the D form. This is the only discernable difference between Proteins D and E, and presumably is responsible for the difference in behavior of these two forms of rat CRISP- 1. These studies demonstrate that the more abundant D form interacts with spermatozoa transiently, possibly with a specific receptor on the sperm surface, consistent with a capacitation-suppressing function during sperm transit and storage in the epididymis, and also confirm a tightly bound population of the E form that could act in the female reproductive tract. (Asian J Androl 2007 July; 9: 508-514)展开更多
The effects of L-cysteine concentration on biohydrogen production by Enterobacterium Bacterium M580 were investigated in batch cultivation.The experimental results showed that L-cysteine could enhance the cell growth,...The effects of L-cysteine concentration on biohydrogen production by Enterobacterium Bacterium M580 were investigated in batch cultivation.The experimental results showed that L-cysteine could enhance the cell growth,hydrogen production rate and hydrogen yield when its concentration was less than 500 mg·L-1,while it had negative effects when its concentration was higher than 500 mg·L-1.The hydrogen production was the highest 1.29 mol·mol-1(H2/glucose) when 300 mg·L-1L-cysteine was added into the culture,and the yield was 9.4% higher than that in the control.The oxidation-reduction potential(ORP) ,which was influenced by L-cysteine,also affected hydrogen production.The ORP values were in the range-300 mV to-150 mV when the L-cysteine concentration was higher than 500 mg·L-1.Although the ORP in this range was favorable for hydrogen production,it was not suitable for the biomass growth.Hence,less hydrogen was produced.When the L-cysteine concentration was lower than 500 mg·L-1,the ORP was more suitable for both biomass growth and hydrogen production.In addition,at least 91%glucose was consumed when L-cysteine was added to the culture media,compared to the 97.37% consumption without L-cysteine added.展开更多
Docetaxel-based combination chemotherapy remains the predominant treatment for castration-resistant prostate cancer. However, taxane-related drug resistance and neurotoxicity have prompted us to develop substitute tre...Docetaxel-based combination chemotherapy remains the predominant treatment for castration-resistant prostate cancer. However, taxane-related drug resistance and neurotoxicity have prompted us to develop substitute treatment strategies. Eg5 (kinesin spindle protein), which is crucial for bipolar spindle formation and duplicated chromosome separation during the early phase of mitosis, has emerged as an attractive target for cancer chemotherapy. The aim of this study was to investigate the anticancer efficacy of $-(methoxytrityl)-L-cysteine (S(MeO)TLC), a novel Eg5 inhibitor in prostate cancer. Eg5 expression was examined in human prostate cancer cell lines and tissue microarrays were constructed from clinical specimens. Antiproliferative activity of S(MeO)TLC in prostate cancer cells was assessed by a cell viability assay. The anticancer effect and inhibitory mechanism of S(MeO)TLC in prostate cancer cells was further explored by Hoechst staining, flow cytometry and immunofluorescence. In addition, the antitumor effect of S(MeO)TLC on subcutaneous xenograft models was assessed. Eg5 expression was identified in PC3, DU145 and LNCaP cells. More than half of prostate cancer clinical specimens displayed Eg5 expression. S(Me0)TLC exhibited more powerful anticancer activity in prostate cancer cells compared with the other four Eg5 inhibitors tested. S(MeO)TLC induced cell death after arresting dividing cells at mitosis with distinct monopolar spindle formation. S(MeO)TLC exhibited its significant inhibitory activity (P〈0.05) on subcutaneous xenograft models also through induction of mitotic arrest. We conclude that Eg5 is a good target for prostate cancer chemotherapy, and S(MeO)TLC is a potent promising anticancer agent in prostate cancer.展开更多
AIM: To evaluate the effectiveness and safety of oral N-acetyl-L-cysteine (NAC) co-administration with mesalamine in ulcerative colitis (UC) patients. METHODS: Thirty seven patients with mild to moderate UC were rando...AIM: To evaluate the effectiveness and safety of oral N-acetyl-L-cysteine (NAC) co-administration with mesalamine in ulcerative colitis (UC) patients. METHODS: Thirty seven patients with mild to moderate UC were randomized to receive a four-wk course of oral mesalamine (2.4 g/d) plus N-acetyl-L-cysteine (0.8 g/d) (group A) or mesalamine plus placebo (group B). Patients were monitored using the Modified Truelove-Witts Severity Index (MTWSI). The primary endpoint was clinical remission (MTWSI ≤ 2) at 4 wk. Secondary endpoints were clinical response (defined as a reduction from baseline in the MTWSI of ≥ 2 points) and drug safety. The serum TNF-α, interleukin-6, interleukin-8 and MCP-1 were evaluated at baseline and at 4 wk of treatment. RESULTS: Analysis per-protocol criteria showed clinical remission rates of 63% and 50% after 4 wk treatment with mesalamine plus N-acetyl-L-cysteine (group A) and mesalamine plus placebo (group B) respectively (OR = 1.71; 95% CI: 0.46 to 6.36; P = 0.19; NNT = 7.7). Analysis of variance (ANOVA) of data indicated a significant reduction of MTWSI in group A (P = 0.046) with respect to basal condition without significant changes in the group B (P = 0.735) during treatment. Clinical responses were 66% (group A) vs 44% (group B) after 4 wk of treatment (OR = 2.5; 95% CI: 0.64 to 9.65; P = 0.11; NNT = 4.5). Clinical improvement in group A correlated with a decrease of IL-8 and MCP-1. Rates of adverse events did not differ significantly between both groups. CONCLUSION: In group A (oral NAC combined with mesalamine) contrarily to group B (mesalamine alone), the clinical improvement correlates with a decrease of chemokines such as MCP-1 and IL-8. NAC addition not produced any side effects.展开更多
AIM: Cysteine peptidase (CP) and its inhibitor (CPI) are a matrix protease that may be associated with colorectal carcinoma invasion and progression, and vitamin E is also a stimulator of the immunological system. Our...AIM: Cysteine peptidase (CP) and its inhibitor (CPI) are a matrix protease that may be associated with colorectal carcinoma invasion and progression, and vitamin E is also a stimulator of the immunological system. Our purpose was to determine the correlation between the expression of cysteine peptidases and their endogenous inhibitors,and the level of vitamin E in sera of patients with colorectal cancer in comparison with healthy individuals.METHODS: The levels of cysteine peptidases and their inhibitors were determined in the sera of patients with primary and metastatic colorectal carcinoma and healthy individuals using fluorogenic substrate, and the level of vitamin E was determined by HPLC.RESULTS: The levels of cysteine peptidases and their inhibitors were significantly higher in the metastatic colorectal cancer patients than that in the healthy controls (P<0.05).The activity of CP increased 2.2-fold, CPI 2.8-fold and vitamin E decreased 3.4-fold in sera of patients with metastasis in comparison with controls. The level of vitamin E in healthy individuals was higher, whereas the activity of cysteine peptidases and their inhibitors associated with complexes was lower than that in patients with cancer of the digestive tract.CONCLUSION: These results suggest that the serum levels of CP and their inhibitors could be an indicator of the prognosis for patients with metastatic colorectal cancer. Vitamin E can be administered prophylactically to prevent digestive tract neoplasmas.展开更多
A spectrophotometric method for the determination of cysteine was developed basing on the reaction of cysteine with cobalt (Ⅱ) in NH 4Cl NH 4OH. The molar absorptivity is 7.98×10 3 L·mol -1 ·cm...A spectrophotometric method for the determination of cysteine was developed basing on the reaction of cysteine with cobalt (Ⅱ) in NH 4Cl NH 4OH. The molar absorptivity is 7.98×10 3 L·mol -1 ·cm -1 at 284 nm. Beer′s law is obeyed for cysteine in the range of 0~2.0×10 -4 mol·L -1 . The method was applied to the assay of cysteine in urine.展开更多
Premature neonates have immature antioxidant enzyme systems rendering them more susceptible to oxidative injury. One key antioxidant is glutathione (GSH). The rate limiting amino acid (AA) in GSH production is thought...Premature neonates have immature antioxidant enzyme systems rendering them more susceptible to oxidative injury. One key antioxidant is glutathione (GSH). The rate limiting amino acid (AA) in GSH production is thought to be cysteine. Critically ill premature neonates who are parenterally fed are often supplemented with additional cysteine, yet the need for cysteine and optimal dose is unknown. This was a prospective, un-blinded, three-group, randomized crossover study aimed to evaluate three doses of cysteine by analyzing red blood cell (RBC) GSH, plasma AA, weight, and nitrogen balance. Neonates were randomized to receive 72 hours of each of the following cysteine doses: 10 mg/g AA, 20 mg/g AA, and 40 mg/g AA. GSH, plasma AAs, weight, and nitrogen balance were evaluated at baseline (after 72 hours of 0 mg/g AA), day three, day six, and day nine. Sixteen patients completed all doses of cysteine, which resulted in significantly increased RBC GSH concentrations over baseline. Plasma concentrations of cystine, total and free cysteine/cystine, glycine and serine increased with cysteine dose. All cysteine doses were associated with adequate weight gain, and positive nitrogen balance. These results are contrary to more recent studies of cysteine effect on RBC GSH concentrations in preterm neonates and infants, but may reflect the severity of illness in our study subjects, where cysteine requirements may be increased.展开更多
基金supported by a grant from Medical Science DataSharing Network,Ministry of Science and Technology,China,No.2005DKA32403Military Medical Scientific Research grants,No.11BJZ32,No.12BJZ271 and No.10BJZ202
文摘Hyperhomocysteinemia and abnormal blood lipids are independent risk factors for stroke. However, whether both factors exert a synergistic effect in the onset of stroke remains unclear. The present study is a retrospective analysJs of 2 089 cases of stroke and 2 089 control cases of simple in- tervertebral disk protrusion using a paired multivariate logistic regression method. Adjusting for known confounding variables including the patients' age, gender, smoking status, alcohol con- sumption status, patient and family medical history, and clinical biochemical indices, elevated ho- mocysteine level was related to the onset of stroke. Patients with elevated homocysteJne levels and abnormal blood lipids showed a 40.9 % increase in the risk for stroke compared to patients with normal homocysteine levels and blood lipids (odds ratio 1.409; 95% confidence interval 1.127-1.761). These results indicate that elevated homocysteine and abnormal blood lipids exert synergistic effects in the onset of stroke. Patients with elevated homocysteine levels and abnormal blood lipids are predisposed to stroke.
文摘AIM:To investigate the potential role of oxidative stress and the possible therapeutic effects of N-acetyl cysteine(NAC),amifostine(AMF)and ascorbic acid(ASC)in methotrexate(MTX)-induced hepatotoxicity.METHODS:An MTX-induced hepatotoxicity model was established in 44 male Sprague Dawley rats by administration of a single intraperitoneal injection of20 mg/kg MTX.Eleven of the rats were left untreated(Model group;n=11),and the remaining rats were treated with a 7-d course of 50 mg/kg per day NAC (MTX+NAC group;n=11),50 mg/kg per single dose AMF(MTX+AMF group;n=11),or 10 mg/kg per day ASC(MTX+ASC group;n=11).Eleven rats that received no MTX and no treatments served as the negative control group.Structural and functional changes related to MTX-and the various treatments were assessed by histopathological analysis of liver tissues and biochemical assays of malondialdehyde(MDA),superoxide dismutase(SOD),catalase,glutathione(GSH)and xanthine oxidase activities and of serum levels of aspartate aminotransferase,alanine aminotransferase,alkaline phosphatase and total bilirubin.RESULTS:Exposure to MTX caused structural and functional hepatotoxicity,as evidenced by significantly worse histopathological scores[median(range)injury score:control group:1(0-3)vs 7(6-9),P=0.001]and significantly higher MDA activity[409(352-466)nmol/g vs 455.5(419-516)nmol/g,P<0.05].The extent of MTX-induced perturbation of both parameters was reduced by all three cytoprotective agents,but only the reduction in hepatotoxicity scores reached statistical significance[4(3-6)for NAC,4.5(3-5)for AMF and 6(5-6)for ASC;P=0.001,P=0.001 and P<0.005vs model group respectively].Exposure to MTX also caused a significant reduction in the activities of GSH and SOD antioxidants in liver tissues[control group:3.02(2.85-3.43)μmol/g and 71.78(61.88-97.81)U/g vs model group:2.52(2.07-3.34)μmol/g and 61.46(58.27-67.75)U/g,P<0.05];however,only the NAC treatment provided significant increases in these antioxidant enzyme activities[3.22(2.54-3.62)μmol/g and 69.22(61.13-100.88)U/g,P<0.05 and P<0.01vs model group respectively].CONCLUSION:MTX-induced structural and functional damage to hepatic tissues in rats may involve oxidative stress,and cytoprotective agents(NAC>AMF>ASC)may alleviate MTX hepatotoxicity.
基金the financial support of the Ministry of Science and Technology of the People's Republic of China(No.2006CB 933100).
文摘Triangular silver nanoprisms were prepared and applied to make colorimetric detection of cysteine based on our findings that cysteine could lead to the blue shift of the dipole plasmon resonance absorption, but other 19 kinds of natural amino acids could not. Cysteine with a concentration 160 nmol/L can result in a color change that can be discerned with naked eyes.
基金Supported by the Natural Science Foundation of Liaoning Province,No.201602817
文摘BACKGROUND Aberrant methylation in DNA regulatory regions could downregulate tumor suppressor genes without changing the sequences.However,our knowledge of secreted protein acidic and rich in cysteine(SPARC)and its aberrant methylation in gastric cancer(GC)is still inadequate.In the present research,we performed fundamental research to clarify the precise function of methylation on SPARC and its significance in GC.AIM To investigate promoter methylation and the effects of the SPARC gene in GC cells and tissues and to evaluate its clinical significance.METHODS Plasmids that overexpressed the SPARC gene were transfected into human GC BGC-823 cells;non-transfected cells were used as a control group(NC group).Quantitative real-time polymerase chain reaction and western blotting(WB)were then used to detect the expression of SPARC.Methylation-specific polymerase chain reaction was executed to analyze the gene promoter methylation status.Cell viability was measured by the cell counting kit-8 assay.The migration and invasion ability of cells were detected by scratch assays and transwell chamber assays,respectively.Cell cycle events and apoptosis were observed with a flow cytometer.RESULTS The expression of SPARC mRNA in GC tissues and cells was significantly lower and showed differing degrees of hypermethylation,respectively,than that in normal adjacent tissues and control cells.Treatment with 5-Aza-2’-deoxycytidine(5-Aza-Cdr)was able to restore the expression of SPARC and reverse promoter hypermethylation.Overexpression of the SPARC gene significantly inhibited proliferation,migration,and invasion of GC cells,while also causing cell cycle arrest and apoptosis;the NC group exhibited the opposite effects.CONCLUSION This study demonstrated that SPARC could function as a tumor suppressor and might be silenced by promoter hypermethylation.Furthermore,in GC cells,SPARC inhibited migration,invasion,and proliferation,caused cell cycle arrest at the G0/G1 phase,and promoted apoptosis.
文摘In this work,a kind of stabilized ferrofluid based on magnetite nanoparticles(mean core and its coating size about 21.9 and 1.6 nm,respectively)was synthesized via coprecipitation method.Cysteine was used as surfactant due to its proper conjunction to the surface of magnetite nanoparticles.Coating density and synthesized ferrofluids were characterized by using transmission electron microscope,thermogravimetry analysis,dynamic light scattering and fourier transform infrared spectroscopy techniques.Magnetic resonance imaging studies show that the synthesized ferrofluid can be used as a potential contrast enhancement agent especially for imaging lymphatic system.
基金the NNSF of China(No.20175031,No.20035010)CAS(CMS-CX200104).
文摘A sensitive and selective chemiluminescence (CL) method was developed for the determination of cysteine. This method is based on that the weak CL of cysteine oxidized with cerium (IV) can be greatly enhanced by quinine, and the total cysteine in human serum can be detected through simply diluting with water, showing a simpler analytical characteristic.
文摘A simple flow injection spectrophotometric method is reported for the determination of cysteine,N-acetyl cysteine and glutathione based on the reduction of Fe(Ⅲ)/ferricyanide,the in situ reduced ions are reacted with unreduced portion of ferricyanide/Fe(Ⅲ) to form soluble Prussian blue,which is monitored at 735 nm.The calibration graphs are linear in the concentration ranges of(1―100)×10-6 mol/L for cysteine and N-acetyl cysteine,and(1―50)×10-6 mol/L for glutathione.The relative standard deviations of 1.8%,2.5% and 1.9% were found for eleven replicate analyses of 5×10-6 mol/L cysteine,N-acetyl cysteine and glutathione.The limits of detection(3σ blank) at 5×10-7 mol/L for cysteine,and 3×10-7 mol/L for N-acetyl cysteine and glutathione were obtained.The proposed method allowed 60 injections/h.The effects of common substances present in pharmaceuticals and human physiological fluids were examined.The method was applied to determining cysteine in pharmaceutical formulations with the recoveries in a range of 97% to 106% and the results obtained are agreed well with labeled values.
文摘A fluorescence ratiometric probe 1 for cysteine (Cys) and homocysteine (Hcy) has been rationally constructed based on intramolecular charge transfer (ICT) mechanism. Upon treatment with Cys/Hcy, probe 1 exhibited a fluorescence ratiometric response, with the emission wavelength displaying a large shift (from 526 nm to 446 nm). When 90 μM Cys were added, the emission ratios (I446/I526) of the probe changed dramatically from 0.01797 to 4.65472. The detection limit was also measured to be 0.18 μM (S/N = 3). The theoretical calculations have confirmed that the ratiometric response of probe 1 to Cys/Hcy is due to the inhibition of ICT process upon the reaction of probe 1 with Cys/Hcy. Furthermore, the fluorescence imaging experiments in living cell demonstrated that probe 1 was favourable for intracellular Cys/Hcy imaging.
文摘Optimal dietary methionine (Met) to lysine (Lys) ratio in presence of elevated dietary cysteine (Cys) levels was derived for meat type growing chicken. Twelve averaged weighed Ross 308 birds (each 50% of male and female per dietary treatment) were utilized in N balance trials. During starter (d10 - 20) and grower period (d25 - 35) five dietary treatments were used. Diets based on uniform mixtures of maize, wheat, soybean meal, potato protein and fish meal were supplemented with crystalline amino acids (AA). In diets 1 - 3, the dietary Cys to Met ratio was set as 85, 95 and 105 to 100, respectively. Diet 4, at a Cys to Met ratio of 105 to 100, was additionally supplemented with betaine (BET) as methyl group donor. Diets 1 - 4 were limiting in Met, diet 5 without L-Lys·HCl addition was limiting in Lys. Individual N-balance data per treatment were utilized for assessing protein quality and efficiency of dietary Met (Diets 1 - 4) or Lys (Diet 5) based on “Goettingen approach”. Elevated dietary Cys supply and supplemented BET failed to improve both dietary protein quality and Met efficiency. The established optimal Met to Lys ratio was on average 34 to 100 for growing chicken during starter and grower period, respectively.
基金Supported by Grants from the Japan Heart Foundation/Novartis Research Award on Molecular and Cellular Cardiology,No.26-007523The Scientific Research Fund of the Chinese Ministry of Education,No.30960128
文摘Cardiac and renal diseases(CRDs) are characterized by extensive remodeling of the extracellular matrix(ECM)architecture of the cardiorenal system. Among the many extracellular proteolytic enzymes present in cardiorenal cells and involved in ECM remodeling, members of the matrix metalloproteinase family and serine protease family have received the most attention. However, recent findings from laboratory and clinical studies have indicated that cysteine protease cathepsins also participate in pathogenesis of the heart and kidney.Deficiency and pharmacological inhibition of cathepsins have allowed their in vivo evaluation in the setting of pathological conditions. Furthermore, recent studiesevaluating the feasibility of cathepsins as a diagnostic tool have suggested that the serum levels of cathepsins L, S and K and their endogenous inhibitor cystatin C have predictive value as biomarkers in patients with coronary artery disease and heart and renal failure. The goal of this review is to highlight recent discoveries regarding the contributions of cathepsins in CRDs, particularly hypertensive heart failure and proteinuric kidney disease.
文摘Rat protein DE is an androgen-dependent cysteine-rich secretory protein (CRISP) synthesized by proximal epididymal regions. DE, also known as CRISP-1, is localized on the equatorial segment of acrosome-reacted spermatozoa and participates in gamete fusion through binding to egg complementary sites. Immunization of rats with DE inhibits fertility and sperm fusion ability, suggesting that DE represents a good epididymal contraceptive target. Recombinant DE fragments and synthetic peptides revealed that DE binds to the egg via a 12-amino acid region of an evolutionarily conserved motif, Signature 2 (S2). The ability of other CRISP to bind to the rat egg was correlated with their S2 amino acid sequences. Although testicular protein Tpx- 1 (CRISP-2) was capable of binding to rodent eggs, human epididymal AEG-related protein (ARP) and helothermine (from lizard saliva) were not. The S2 region presented only two substitutions in Tpx-1 and four in ARP and helothermine, compared with the DE S2, suggesting that this amino acid sequence was relevant for egg interaction. Studies with Tpx- 1 and anti-Tpx- 1 revealed the participation of this protein in gamete fusion through binding to complementary sites in the egg. In competition studies, DE reduced binding of Tpx- 1 dose-dependently, indicating that both CRISP share the egg complementary sites. That anti-DE and anti-Tpx-1 inhibit sperm-egg fusion while recognizing only the corresponding proteins, suggests functional cooperation between these homologous CRISP to ensure fertilization success. These results increase our understanding of the molecular mechanisms of gamete fusion and contribute to the development of new and safer fertility regulating methods. (Asian J Androl 2007 July; 9: 528-532)
文摘Cryopreservation is associated with the production of reactive oxygen species, which leads to lipid peroxidation of the sperm membrane and consequently a reduction in sperm motility and decreased fertility potential. The aim of this study was to determine the optimal concentration of L-cysteine needed for cryopreservation of boar semen. Twelve boars provided semen of proven motility and morphology for this study. The semen was divided into four portions in which the lactose-egg yolk (LEY) extender used to resuspend the centrifuged sperm pellet was supplemented with various concentrations of L-cysteine to reach 0 mmol L^-1 (group Ⅰ, control), 5 mmol L^-1 (group Ⅱ), 10 mmol L^-1 (group Ⅲ) and 15 mmol L^-1 (group Ⅳ). Semen suspensions were loaded in straws (0.5 mL) and placed in a controlled-rate freezer. After cryopreservation, frozen semen samples were thawed and investigated for progressive motility, viability using SYBR-14/EthD-1 staining and acrosome integrity using FITC-PNA/EthD-1 staining. There was a significantly higher (P 〈 0.01) percentage of progressive motility, viability and acrosomal integrity in two L-cysteine-supplemented groups (group Ⅱ and group Ⅲ) compared with the control. There was a biphasic effect of L-cysteine, with the highest percentage of progressive motility, viability and acrosomal integrity in group Ⅲ. In conclusion, 5 or 10 mmol L^-1 was the optimum concentration of L-cysteine to be added to the LEY extender for improving the quality of frozen-thawed boar semen.
文摘Cysteine-rich secretory protein-1 (CRISP-1) is a glycoprotein secreted by the epididymal epithelium. It is a member of a large family of proteins characterized by two conserved domains and a set of 16 conserved cysteine residues. In mammals, CRISP-1 inhibits sperm-egg fusion and can suppress sperm capacitation. The molecular mechanism of action of the mammalian CRISP proteins remains unknown, but certain non-mammalian CRISP proteins can block ion channels. In the rat, CRISP-1 comprises two forms referred to as Proteins D and E. Recent work in our laboratory demonstrates that the D form of CRISP-1 associates transiently with the sperm surface, whereas the E form binds tightly. When the spermatozoa are washed, the E form of CRISP-1 persists on the sperm surface after all D form has dissociated. Cross-linking studies demonstrate different protein-protein interaction patterns for D and E, although no binding partners for either protein have yet been identified. Mass spectrometric analyses revealed a potential post-translational modification on the E form that is not present on the D form. This is the only discernable difference between Proteins D and E, and presumably is responsible for the difference in behavior of these two forms of rat CRISP- 1. These studies demonstrate that the more abundant D form interacts with spermatozoa transiently, possibly with a specific receptor on the sperm surface, consistent with a capacitation-suppressing function during sperm transit and storage in the epididymis, and also confirm a tightly bound population of the E form that could act in the female reproductive tract. (Asian J Androl 2007 July; 9: 508-514)
基金Supported by the National High Technology Research and Development Program of China(2006AA02Z246 2007AA03Z456) the National Natural Science Foundation of China(20776119)+2 种基金 the Specialized Research Fund for the Doctoral Program of Higher Education of China(20096101120023) Shaanxi Provincial Natural Science Foundation(SJ08B03) Shaanxi Key Subject Program China
文摘The effects of L-cysteine concentration on biohydrogen production by Enterobacterium Bacterium M580 were investigated in batch cultivation.The experimental results showed that L-cysteine could enhance the cell growth,hydrogen production rate and hydrogen yield when its concentration was less than 500 mg·L-1,while it had negative effects when its concentration was higher than 500 mg·L-1.The hydrogen production was the highest 1.29 mol·mol-1(H2/glucose) when 300 mg·L-1L-cysteine was added into the culture,and the yield was 9.4% higher than that in the control.The oxidation-reduction potential(ORP) ,which was influenced by L-cysteine,also affected hydrogen production.The ORP values were in the range-300 mV to-150 mV when the L-cysteine concentration was higher than 500 mg·L-1.Although the ORP in this range was favorable for hydrogen production,it was not suitable for the biomass growth.Hence,less hydrogen was produced.When the L-cysteine concentration was lower than 500 mg·L-1,the ORP was more suitable for both biomass growth and hydrogen production.In addition,at least 91%glucose was consumed when L-cysteine was added to the culture media,compared to the 97.37% consumption without L-cysteine added.
文摘Docetaxel-based combination chemotherapy remains the predominant treatment for castration-resistant prostate cancer. However, taxane-related drug resistance and neurotoxicity have prompted us to develop substitute treatment strategies. Eg5 (kinesin spindle protein), which is crucial for bipolar spindle formation and duplicated chromosome separation during the early phase of mitosis, has emerged as an attractive target for cancer chemotherapy. The aim of this study was to investigate the anticancer efficacy of $-(methoxytrityl)-L-cysteine (S(MeO)TLC), a novel Eg5 inhibitor in prostate cancer. Eg5 expression was examined in human prostate cancer cell lines and tissue microarrays were constructed from clinical specimens. Antiproliferative activity of S(MeO)TLC in prostate cancer cells was assessed by a cell viability assay. The anticancer effect and inhibitory mechanism of S(MeO)TLC in prostate cancer cells was further explored by Hoechst staining, flow cytometry and immunofluorescence. In addition, the antitumor effect of S(MeO)TLC on subcutaneous xenograft models was assessed. Eg5 expression was identified in PC3, DU145 and LNCaP cells. More than half of prostate cancer clinical specimens displayed Eg5 expression. S(Me0)TLC exhibited more powerful anticancer activity in prostate cancer cells compared with the other four Eg5 inhibitors tested. S(MeO)TLC induced cell death after arresting dividing cells at mitosis with distinct monopolar spindle formation. S(MeO)TLC exhibited its significant inhibitory activity (P〈0.05) on subcutaneous xenograft models also through induction of mitotic arrest. We conclude that Eg5 is a good target for prostate cancer chemotherapy, and S(MeO)TLC is a potent promising anticancer agent in prostate cancer.
基金Direccion General de Investigación, No. SAF2004-06289Contract Art. 83 L.O.U. with Cytochrome, No. UAH 64/2003 and the Instituto de Salud Carlos Ⅲ, No. C03/02
文摘AIM: To evaluate the effectiveness and safety of oral N-acetyl-L-cysteine (NAC) co-administration with mesalamine in ulcerative colitis (UC) patients. METHODS: Thirty seven patients with mild to moderate UC were randomized to receive a four-wk course of oral mesalamine (2.4 g/d) plus N-acetyl-L-cysteine (0.8 g/d) (group A) or mesalamine plus placebo (group B). Patients were monitored using the Modified Truelove-Witts Severity Index (MTWSI). The primary endpoint was clinical remission (MTWSI ≤ 2) at 4 wk. Secondary endpoints were clinical response (defined as a reduction from baseline in the MTWSI of ≥ 2 points) and drug safety. The serum TNF-α, interleukin-6, interleukin-8 and MCP-1 were evaluated at baseline and at 4 wk of treatment. RESULTS: Analysis per-protocol criteria showed clinical remission rates of 63% and 50% after 4 wk treatment with mesalamine plus N-acetyl-L-cysteine (group A) and mesalamine plus placebo (group B) respectively (OR = 1.71; 95% CI: 0.46 to 6.36; P = 0.19; NNT = 7.7). Analysis of variance (ANOVA) of data indicated a significant reduction of MTWSI in group A (P = 0.046) with respect to basal condition without significant changes in the group B (P = 0.735) during treatment. Clinical responses were 66% (group A) vs 44% (group B) after 4 wk of treatment (OR = 2.5; 95% CI: 0.64 to 9.65; P = 0.11; NNT = 4.5). Clinical improvement in group A correlated with a decrease of IL-8 and MCP-1. Rates of adverse events did not differ significantly between both groups. CONCLUSION: In group A (oral NAC combined with mesalamine) contrarily to group B (mesalamine alone), the clinical improvement correlates with a decrease of chemokines such as MCP-1 and IL-8. NAC addition not produced any side effects.
文摘AIM: Cysteine peptidase (CP) and its inhibitor (CPI) are a matrix protease that may be associated with colorectal carcinoma invasion and progression, and vitamin E is also a stimulator of the immunological system. Our purpose was to determine the correlation between the expression of cysteine peptidases and their endogenous inhibitors,and the level of vitamin E in sera of patients with colorectal cancer in comparison with healthy individuals.METHODS: The levels of cysteine peptidases and their inhibitors were determined in the sera of patients with primary and metastatic colorectal carcinoma and healthy individuals using fluorogenic substrate, and the level of vitamin E was determined by HPLC.RESULTS: The levels of cysteine peptidases and their inhibitors were significantly higher in the metastatic colorectal cancer patients than that in the healthy controls (P<0.05).The activity of CP increased 2.2-fold, CPI 2.8-fold and vitamin E decreased 3.4-fold in sera of patients with metastasis in comparison with controls. The level of vitamin E in healthy individuals was higher, whereas the activity of cysteine peptidases and their inhibitors associated with complexes was lower than that in patients with cancer of the digestive tract.CONCLUSION: These results suggest that the serum levels of CP and their inhibitors could be an indicator of the prognosis for patients with metastatic colorectal cancer. Vitamin E can be administered prophylactically to prevent digestive tract neoplasmas.
文摘A spectrophotometric method for the determination of cysteine was developed basing on the reaction of cysteine with cobalt (Ⅱ) in NH 4Cl NH 4OH. The molar absorptivity is 7.98×10 3 L·mol -1 ·cm -1 at 284 nm. Beer′s law is obeyed for cysteine in the range of 0~2.0×10 -4 mol·L -1 . The method was applied to the assay of cysteine in urine.
文摘Premature neonates have immature antioxidant enzyme systems rendering them more susceptible to oxidative injury. One key antioxidant is glutathione (GSH). The rate limiting amino acid (AA) in GSH production is thought to be cysteine. Critically ill premature neonates who are parenterally fed are often supplemented with additional cysteine, yet the need for cysteine and optimal dose is unknown. This was a prospective, un-blinded, three-group, randomized crossover study aimed to evaluate three doses of cysteine by analyzing red blood cell (RBC) GSH, plasma AA, weight, and nitrogen balance. Neonates were randomized to receive 72 hours of each of the following cysteine doses: 10 mg/g AA, 20 mg/g AA, and 40 mg/g AA. GSH, plasma AAs, weight, and nitrogen balance were evaluated at baseline (after 72 hours of 0 mg/g AA), day three, day six, and day nine. Sixteen patients completed all doses of cysteine, which resulted in significantly increased RBC GSH concentrations over baseline. Plasma concentrations of cystine, total and free cysteine/cystine, glycine and serine increased with cysteine dose. All cysteine doses were associated with adequate weight gain, and positive nitrogen balance. These results are contrary to more recent studies of cysteine effect on RBC GSH concentrations in preterm neonates and infants, but may reflect the severity of illness in our study subjects, where cysteine requirements may be increased.