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1.
Article de Chinois | MEDLINE | ID: mdl-34218566

RÉSUMÉ

Objective: To explore the CT grading method of small opacity profusion of pneumoconiosis, and draw up the corresponding CT reference film. Methods: In December 2019, Three hundred thirty-seven cases of pneumoconosis and suspected pneumoconiosis were examined by chest radiography and Computed Tomography (CT) in the same period. According to Diagnosis of Occupational Pneumoconiosis (GBZ 70-2015) , small opacity profusion of pneumoconiosis in each zone of lung was divided. On CT scans, it was divided into 5 grades of 0, 0+, 1, 2 and 3. Grade 0 corresponded to Sub-grade 0/- and Sub-grade 0/0 of Grade 0 in chest radiograph. Grade 0+ was equivalent to Sub-grade 0/1 of Grade 0. Grade 1, 2, 3 were equivalent to Grade 1, 2 and 3, respectively (including each sub-grade) . The CT image quality of each zone of lung was divided into 1 to 4 levels. Results of level 4 were not included in statistical analyses.Based on the results of small opacity profusion in each zone of lung, consistency analysis was performed between chest radiograph and CT. The selection method of reference films was developed. Based on the types and grades of small opacity, the final reference films were determined. Results: There were 1877 zones of lung with CT image quality from level 1 to 3, including 335 in upper right, 319 in middle right, 284 in lower right, 334 in upper left, 320 in middle left and 286 in lower left. The Kappa values of small opacity profusion in upper right zone, upper left zone, left middle zone, and lower left zone were all between 0.4-0.75. In middle right zone and lower right zone, they were all above 0.75.Among all 6 zones of lung, the diagnostic concordance rates between CT and chest radiograph were all above 80%.The corresponding CT reference films were proposed, including type p and q in Grade 2 and 3, type r in Grade 2, type s and t in Grade 0+ to 3. Conclusion: The CT grading method for small opacity profusion of pneumoconiosis is feasible, and the application value of its reference films needs to be further verified.


Sujet(s)
Pneumoconiose , Humains , Poumon , Pneumoconiose/imagerie diagnostique , Radiographie , Tomodensitométrie
2.
Eur Rev Med Pharmacol Sci ; 24(21): 11041-11051, 2020 11.
Article de Anglais | MEDLINE | ID: mdl-33215419

RÉSUMÉ

OBJECTIVE: Renal cell carcinoma (RCC) is the most common kidney malignancy that frequently leads to metastasis. Increasing evidence has shown that long non-coding RNAs (lncRNAs) play crucial roles affecting the progression of RCC. The role of lncRNA DUXAP10 in the evolution of RCC has not been defined yet. This project was designed to clarify the effects of DUXAP10 on the proliferation and tumorigenesis of RCC. PATIENTS AND METHODS: We examined the expression of DUXAP10 in the Cancer Genome Atlas (TCGA) and ONCOMINE oncology databases. Then, we performed quantitative reverse-transcription polymerase chain reaction (qRT-PCR) to evaluate DUXAP10 expression in human RCC tissues and cell lines. The correlation between the expression of DUXAP10 and clinical characteristics of RCC patients was analyzed by univariate and Kaplan-Meier analyses. To unveil the biological function of DUXAP10 in cell cycle progression, cell growth, and invasion of RCC, we conducted knockdown experiments in vitro. qRT- PCR and western blotting assays were performed to further investigate the function of DUXAP10 in cancer biology. RESULTS: The data from TCGA showed that the expression of DUXAP10 was upregulated in tissues of RCC compared with normal tissues. Moreover, ONCOMINE database analysis indicated that high DUXAP10 levels were correlated with high clinical stages, inferior TNM classification, and poor overall survival. Furthermore, the results indicated that knockdown of DUXAP10 remarkably inhibited the RCC cell growth, mobility, and invasion, in association with the upregulation of E-cadherin and downregulation of cyclin D, cyclin E, CDK4, N-cadherin, and vimentin. CONCLUSIONS: Our findings highlight the oncogenic role of DUXAP10 in RCC and that DUXAP10 may serve as a novel predictive biomarker and therapeutic target for RCC.


Sujet(s)
Néphrocarcinome/métabolisme , Régulation négative , Tumeurs du rein/métabolisme , ARN long non codant/métabolisme , Apoptose , Néphrocarcinome/anatomopathologie , Mouvement cellulaire , Prolifération cellulaire , Femelle , Humains , Tumeurs du rein/anatomopathologie , Mâle , Adulte d'âge moyen , ARN long non codant/génétique
3.
Eur Rev Med Pharmacol Sci ; 23(9): 3699-3708, 2019 May.
Article de Anglais | MEDLINE | ID: mdl-31114994

RÉSUMÉ

OBJECTIVE: Long non-coding RNA DUXAP10 plays a significant role in the tumorigenesis and development of human cancer. The present study was performed to investigate the role of DUXAP10 in biological functions and underlying molecular mechanisms of prostate cancer cells. MATERIALS AND METHODS: First, the quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to detect the expression of DUXAP10 in human prostate cancer cell lines 22RV1, PC3, and DU145. Subsequently, small interfering RNAs (siRNAs) targeting at DUXAP10 mRNA were used to downregulate DUXAP10 expression. Then, the biological functions of DUXAP10 in prostate cancer cells, proliferation, migration, and apoptosis were studied by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, colony-formation assay, cell cycle analysis, transwell migration assay, wound healing assay, and cell apoptosis assay, respectively. Finally, qRT-PCR analysis and Western blot assay were used to investigate the molecular mechanisms of DUXAP10 underlying the progression of prostate cancer. RESULTS: Results showed that the expression of DUXAP10 was higher in PC3 and DU145 cell lines than that in the 22RV1 cell line. Additionally, the knockdown of DUXAP10 could remarkably inhibit the proliferation, migration, and induce apoptosis of prostate cancer cells, and significantly increase the number of G0/G1 cells in PC3 and DU145 cell lines. Moreover, DUXAP10 could promote the development of prostate cancer by regulating the process of epithelial-mesenchymal transition (EMT). CONCLUSIONS: The findings of this study suggested that the down-regulation of DUXAP10 expression suppressed the progression of prostate cancer by inhibiting cell proliferation, migration and promote cell apoptosis.


Sujet(s)
Apoptose , Mouvement cellulaire , Tumeurs de la prostate/métabolisme , ARN long non codant/métabolisme , Apoptose/génétique , Mouvement cellulaire/génétique , Prolifération cellulaire/génétique , Évolution de la maladie , Régulation négative , Humains , Mâle , Tumeurs de la prostate/génétique , Tumeurs de la prostate/anatomopathologie , ARN long non codant/génétique , Cellules cancéreuses en culture
4.
Zhonghua Yi Xue Za Zhi ; 98(24): 1962-1964, 2018 Jun 26.
Article de Chinois | MEDLINE | ID: mdl-29996291

RÉSUMÉ

Objective: Precise renal puncture is an essential but challenging step for successful percutaneous nephrolithotomy. We evaluated the efficiency of a novel real-time navigation system using Mixed Reality(MR) technology for human phantom kidney puncture. Methods: One human kidney phantom underwent MR-assisted percutaneous collecting system puncture. Two punctures were performed by each of 6 surgeons in the randomize selected upper, middle or lower calyces. Outcome measurements were the number of attempts for renal puncture, the time needed to evaluate the trajectory and to perform percutaneous puncture. Results: A total of 12 punctures were performed successfully using MR-Assisted Guidance. Median evaluation time and renal puncture time for the selected calyces was 13 (range 11 to 19) and 19 seconds (range 15 to 44), respectively. One or Two attempts were needed to achieve a successful renal puncture for all of the surgeons. Conclusions: The proposed MR-assisted guidance solution for renal collecting system puncture proved to be accurate, simple and quick. The inherent limitations of traditional X - ray and ultrasonic technology can be overcome.


Sujet(s)
Rein , Ponctions , Humains , Calculs rénaux , Néphrolithotomie percutanée
5.
Andrologia ; 50(2)2018 Mar.
Article de Anglais | MEDLINE | ID: mdl-28776758

RÉSUMÉ

To investigate the effect of a high-fat diet and aerobic exercise intervention and its related mechanism on rat germ cell apoptosis. Forty male Sprague-Dawley rats were randomly divided into control group, high-fat diet group, control exercise group and high-fat exercise group. Rats were fed with high-fat diet or were given weight-free swimming. The levels of TG, TC, HDL, LDL and IL-6 in serum of rats were measured. The body weight, body length and inguinal fat weight were measured to calculate the Lee's index and lipid/body weight ratio. The expression of IL-6 mRNA in inguinal fat and IL-6R,Bcl-2 and Bax mRNA in testis was detected by RT-PCR. The morphological structure of testis was observed, and the Johnsen's ten-point score was calculated by HE staining, and the germ cell apoptosis was detected by TUNEL method. We got from the experimental results: a high-fat diet induces obesity and lipid metabolism disorder, alters testis morphological structure and increases germ cell apoptosis in rats. Aerobic exercise improves the lipid metabolism disorder and interferes with germ cell apoptosis by reducing interleukin-6 and interleukin-6 receptor expression.


Sujet(s)
Interleukine-6/métabolisme , Obésité/thérapie , Récepteurs à l'interleukine-6/métabolisme , Spermatozoïdes/anatomopathologie , Testicule/métabolisme , Animaux , Apoptose , Alimentation riche en graisse/effets indésirables , Modèles animaux de maladie humaine , Humains , Méthode TUNEL , Métabolisme lipidique , Mâle , Obésité/étiologie , Obésité/métabolisme , Conditionnement physique d'animal/psychologie , Rats , Rat Sprague-Dawley , Testicule/cytologie
6.
Eur J Surg Oncol ; 41(8): 1013-9, 2015 Aug.
Article de Anglais | MEDLINE | ID: mdl-26005133

RÉSUMÉ

AIMS: Desmoid-type fibromatoses (DFs) are rare soft-tissue neoplasms with frequent local recurrence. We sought to determine the prognostic factors that are predictive of recurrence-free survival (RFS) for these tumors. METHODS: One hundred and fourteen consecutive patients with sporadic DF who received macroscopically complete resection (R0/R1) at a single tertiary hospital between 1985 and 2014 were included. A total of 10 clinical and pathological parameters were analyzed. Histologic slides and the margin status were re-checked; close margins (≤1-mm clearance) were noted separately and were considered together with the R1 margin. RESULTS: The median follow-up interval was 72.5 months. Thirty-five (30.7%) patients had a local recurrence. The 2-, 5- and 10-year RFSs were 75.2%, 72.1% and 67.0%, respectively. In univariate analysis, age, tumor size, tumor site, margin status and presence of lesions at multiple sites had a significant impact on RFS. In multiple analysis, younger age (age<30 vs. age≥50 years: hazard ratio [HR] = 4.96; 95% confidence interval [95% CI], 1.50-16.4; p = 0.009); an extra-abdominal site (extra-abdominal site vs. other sites: HR = 4.08; 95% CI, 1.49-11.2; p = 0.006); larger tumor size (≥8 cm vs. <8 cm: HR = 2.43; 95% CI, 1.15-5.13; p = 0.021); and close or positive margin status (close margin/R1 vs. R0: HR = 2.64; 95% CI, 1.11-6.25; p = 0.027) were independent, unfavorable prognostic factors. CONCLUSIONS: Different prognostic subgroups were identified that allow for the better selection of favorable therapeutic strategies. The role of the margin status should be considered with caution and should be based on a more precise pathological result.


Sujet(s)
Tumeurs de l'abdomen/diagnostic , Fibromatose agressive/diagnostic , Laparotomie/méthodes , Récidive tumorale locale/diagnostic , Appréciation des risques/méthodes , Tumeurs de l'abdomen/chirurgie , Adolescent , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Enfant , Chine/épidémiologie , Survie sans rechute , Femelle , Fibromatose agressive/épidémiologie , Fibromatose agressive/chirurgie , Études de suivi , Humains , Incidence , Mâle , Adulte d'âge moyen , Récidive tumorale locale/épidémiologie , Pronostic , Études rétrospectives , Facteurs de risque , Taux de survie/tendances , Facteurs temps , Jeune adulte
7.
J Clin Pharm Ther ; 33(3): 251-61, 2008 Jun.
Article de Anglais | MEDLINE | ID: mdl-18452412

RÉSUMÉ

BACKGROUND: Persistence with Hepatitis C therapy has been identified as a key variable for predicting treatment success. The primary purpose of this study was to assess the persistence with therapy for patients undergoing hepatitis C treatment in the VA healthcare system with two forms of combination therapies: peginterferon alfa-2a with Ribavirin (peg-IFN alpha-2a/Rib) and peginterferon alpha-2b with Ribavirin (peg-IFN alpha-2b/Rib). METHODS: A retrospective cohort study design was used to analyse persistence in VA patients undergoing hepatitis C therapy during FY 2003-2004 using a large national VA data set. Stringent inclusion and exclusion criteria along with various defining variables were used to identify the inception cohort. Persistence rates were calculated for each of the two treatment groups at 3, 6, 9 and 11 months using the Kaplan-Meier method. Likelihood ratio test of equality between the two treatment groups was performed to detect any differences in persistence rates. RESULTS: A total of 5816 hepatitis C patients formed the inception cohort. Persistence rates for the overall duration showed significantly higher rates for patients on peg-IFN alpha-2a/Rib than peg-IFN alpha-2b/Rib. Cox regression analysis also showed favourable hazard ratio of persistence (0.88) for peg-IFN alpha-2a/Rib over peg-IFN alpha-2b/Rib. CONCLUSION: Peg alfa-2A/Rib showed slightly higher persistence rates for the overall duration of treatment as compared to Peg alfa-2B/Rib. However the differences, even though statistically significant, are small and not likely to translate into any substantial clinical advantage. Further research involving other approaches is required to confirm these findings.


Sujet(s)
Antiviraux/usage thérapeutique , Hépatite C/traitement médicamenteux , Interféron alpha/usage thérapeutique , Observance par le patient , Polyéthylène glycols/usage thérapeutique , Ribavirine/usage thérapeutique , Adolescent , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Antiviraux/administration et posologie , Études de cohortes , Calendrier d'administration des médicaments , Association de médicaments , Femelle , Humains , Interféron alpha-2 , Interféron alpha/administration et posologie , Mâle , Adulte d'âge moyen , Abandon des soins par les patients , Polyéthylène glycols/administration et posologie , Protéines recombinantes , Études rétrospectives , Ribavirine/administration et posologie , États-Unis , Department of Veterans Affairs (USA)
8.
J Urol ; 166(6): 2495-9, 2001 Dec.
Article de Anglais | MEDLINE | ID: mdl-11696817

RÉSUMÉ

PURPOSE: We analyzed the gene expression of the glycoprotein termed secreted protein, acidic and rich in cysteine (SPARC), also called osteonectin and BM40, in bladder cancer and its relationship with conventional clinical-histopathological manifestations, evaluated its prognostic value for patient outcome and determined the possible mechanism underlying the effect of SPARC on bladder cancer progression. MATERIALS AND METHODS: Tissue samples from 63 patients with bladder cancer were used for analysis. Gene expression levels of SPARC and matrix metalloproteinase-2 were analyzed using reverse transcription-polymerase chain reaction. Correlations of the expression of SPARC with histopathological findings or patient outcome and with matrix metalloproteinase-2 were evaluated. RESULTS: Significantly higher expression of SPARC was observed in grades 3 and 2 than in grade 1 tumors (p <0.001 and <0.05, respectively). Stage T2 or greater invasive tumors expressed a significantly higher level of SPARC than stages T1 or less superficial tumors (p <0.0001). Patients in whom the lesions showed high SPARC expression had a significantly worse prognosis than those with low SPARC expression disease (p <0.0001). Even in those with invasive bladder cancer high SPARC expression was associated with significantly worse survival than low expression (p <0.01). Moreover, gene expression of SPARC significantly correlated with matrix metalloproteinase-2 gene expression (p <0.0001), implying that regulation of matrix metalloproteinase-2 expression may be a possible mechanism underlying the effect of SPARC on bladder cancer progression. CONCLUSIONS: A significant correlation was detected of the gene expression level of SPARC with histological grade, pathological stage and bladder cancer prognosis. SPARC may have an important role in bladder cancer progression and provide some additional information in patients with bladder cancer.


Sujet(s)
Carcinome transitionnel/génétique , Régulation de l'expression des gènes tumoraux/génétique , Ostéonectine/génétique , Tumeurs de la vessie urinaire/génétique , Sujet âgé , Sujet âgé de 80 ans ou plus , Carcinome transitionnel/métabolisme , Carcinome transitionnel/anatomopathologie , Évolution de la maladie , Femelle , Humains , Mâle , Matrix metalloproteinase 2/biosynthèse , Matrix metalloproteinase 2/génétique , Adulte d'âge moyen , Ostéonectine/biosynthèse , Pronostic , RT-PCR , Tumeurs de la vessie urinaire/métabolisme , Tumeurs de la vessie urinaire/anatomopathologie
9.
J Clin Microbiol ; 31(1): 97-101, 1993 Jan.
Article de Anglais | MEDLINE | ID: mdl-8417038

RÉSUMÉ

The Premier enzyme immunoassay (Meridian Diagnostics, Inc., Cincinnati, Ohio) was compared with a latex agglutination assay (CALAS; Meridian) for the ability to detect cryptococcal capsular polysaccharide antigen (CrAg) in serum and cerebrospinal fluid (CSF). A total of 594 specimens (471 serum samples and 123 CSF samples) obtained from 430 patients, most of whom were at risk for or had AIDS, were tested in parallel by both systems. Both tests were independently evaluated for their ability to (i) detect CrAg when used as a screening test and (ii) quantitate the CrAg present when used as a titration assay. Chart review to assess clinical outcome after the time of specimen collection was conducted for all patients. When both assays were used as screening assays, 103 serum samples and 18 CSF samples were positive and 356 serum samples and 104 CSF specimens were negative by both assays (97.8% concordance). Thirteen specimens (12 serum samples, 1 CSF sample) gave discrepant screening results. When the tests were used as semiquantitative assays for titer determinations, the CrAg titers determined by the enzyme immunoassay were generally higher than those obtained with the latex agglutination assay. In summary, results obtained with the enzyme immunoassay correlated well with those obtained with the latex agglutination test for screening for the presence of CrAg and for determining the titer of CrAg in serum or CSF.


Sujet(s)
Antigènes fongiques/sang , Antigènes fongiques/liquide cérébrospinal , Cryptococcus neoformans/immunologie , Techniques immunoenzymatiques , Méningite cryptococcique/diagnostic , Syndrome d'immunodéficience acquise/complications , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Études d'évaluation comme sujet , Faux négatifs , Faux positifs , Femelle , Humains , Techniques immunoenzymatiques/normes , Tests au latex/normes , Mâle , Méningite cryptococcique/sang , Méningite cryptococcique/liquide cérébrospinal , Méningite cryptococcique/immunologie , Adulte d'âge moyen , Polyosides/immunologie , Sensibilité et spécificité
10.
J Inorg Biochem ; 43(4): 723-30, 1991 Sep.
Article de Anglais | MEDLINE | ID: mdl-1779228

RÉSUMÉ

Dicopper complexes of the following benzimidazole-containing ligands have been studied as possible models for the active site of hemocyanin: EDTB (N,N,N',N'-tetrakis-(2-benzimidazolylmethyl)-1,2-ethanediamine), EGTB (1,1,10,10-tetrakis-(2-benzimidazolylmethyl)-1,10-diaza-4,7- dioxadecane), and MEGTB (1,1,10,10-tetrakis-(1-methylbenzimidazol-2-y lmethyl)-1,10-diaza-4,7-dioxadecane). The initial oxygenation product of Cu2(EDTB)(ClO4)2 in Me2SO gives optical absorption maxima at 315 nm (epsilon = 3750 M-1 cm-1) and 690 nm (epsilon = 100 M-1 cm-1). The fluorescence emission intensities of Cu2(EDTB)(ClO4)2 at 400 and 700 nm (excitation at 350 nm) decreases rapidly on exposure to air. This suggests oxidation of Cu2(I) to Cu2(II). The x-ray absorption edge spectra suggest that both coppers in the oxygenation product, analyzed as Cu2(EDTB)(ClO4)2(O).3H2O, are Cu(II). From spectrophotometric titration of Cu2(MEGTB)Cl4 with azide, formation constant of the Cu2(MEGTB)N3Cl3 complex has been obtained. Data from cyclic voltammetry experiments suggest that in the presence of azide, Cu(II)(N3)Cu(II) species is present.


Sujet(s)
Benzimidazoles/composition chimique , Cuivre/composition chimique , Ligands , Structure moléculaire
11.
Proc Natl Sci Counc Repub China B ; 8(4): 319-23, 1984 Oct.
Article de Anglais | MEDLINE | ID: mdl-6571593

RÉSUMÉ

Cyanide (5 X 10(-3) M) and thioacetamide (5 X 10(-3) M) increase the P50 values (P02 required for 50% oxygenation) of hemocyanin by 100%, respectively. Using an ion-exchange method involving 14CN-, we have found that cyanide forms a 1:1 complex with hemocyanin in the concentration range examined: Kf = 2.3 X Mw M-1 at room temperature, where Kf is association constant and Mw is molecular weight of hemocyanin. This strong binding of cyanide to hemocyanin is to be expected from the effect of this ion on the oxygenation of hemocyanin. The effects of manganese(II) ion and fluoride on the oxygenation of hemocyanin are found to be weak. The nmr measurements, however, suggest that manganese(II) ion does have some interactions with the active site of hemocyanin.


Sujet(s)
Acétamides/pharmacologie , Cyanures/pharmacologie , Hémocyanine/métabolisme , Manganèse/métabolisme , Escargots/analyse , Thioacétamide/pharmacologie , Animaux , Fluorures/pharmacologie , Oxydoréduction , Oxygène/métabolisme
14.
Bioinorg Chem ; 8(2): 133-8, 1978.
Article de Anglais | MEDLINE | ID: mdl-25095

RÉSUMÉ

Solutions of Busycon canaliculatum have been studied by light scattering. In 0.05 M Trizma buffer +0.1 M NaCl at pH 7.0 at 14 degrees, the weight-average molecular weight is 8.9 X 10(6). In the presence of added CaCl2 (0.02 M), the molecular weight of the protein increases to 10.7 X 10(6), and the second virial coefficient is reduced. At pH 9.95, the molecular weights with and without 0.02 M CaCl2, are 3.7 X 10(6) and 1.3 X 10(6), respectively; and the effect of Ca++ in reducing the second virial coefficient is much greater than at pH 7.0. These results can be understood on the basis that at pH 7.0, ca++ increases the association of hemocyanin, by binding and intermolecular linkage through the carboxyl groups of protein side chains. At pH 9.95, amino groups are deprotonated and therefore also become available for Ca++ binding. The relative effect of Ca++ in enhancing the association of hemocyanin therefore becomes greater at the higher pH.


Sujet(s)
Chlorure de calcium , Hémocyanine , Animaux , Hémolymphe , Concentration en ions d'hydrogène , Lumière , Mathématiques , Masse moléculaire , Diffusion de rayonnements , Escargots
16.
Biochemistry ; 15(24): 5337-43, 1976 Nov 30.
Article de Anglais | MEDLINE | ID: mdl-187214

RÉSUMÉ

Oxidation studies of hemoglobin by Cu(II) indicate that for horse hemoglobin, up to a Cu(II)/heme molar ratio of 0.5, all of the Cu(II) added is used to rapidly oxidize the heme. On the other hand, most of the Cu(II) added to human hemoglobin at low Cu(II)/heme molar ratios is unable to oxidize the heme. Only at Cu(II)/heme molar ratios greater than 0.5 does the amount of oxidation per added Cu(II) approach that of horse hemoglobin. At the same time, binding studies indicate that human hemoglobin has an additional binding site involving one copper for every two hemes, which has a higher copper affinity than the single horse hemoglobin binding site. The Cu(II) oxidation of human hemoglobin is explained utilizing this additional binding site by a mechanism where a transfer of electrons cannot occur between the heme and the Cu(II) bound to the high affinity human binding site. The electron transfer must involve the Cu(II) bound to the lower affinity human hemoglobin binding site, which is similar to the only horse hemoglobin site. The involvement of beta-2 histidine in the binding of this additional copper is indicated by a comparison of the amino acid sequences of various hemoglobins which possess the additional site, with the amino acid sequences of hemoglobins which do not possess the additional site. Zn(II), Hg(II), and N-ethylmaleimide (NEM) are found to decrease the Cu(II) oxidation of hemoglobin. The sulfhydryl reagents, Hg(II) and NEM, produce a very dramatic decrease in the rate of oxidation, which can only be explained by an effect on the rate for the actual transfer of electrons between the Cu(II) and the Fe(II). The effect of Zn(II) is much smaller and can, for the most part, be explained by the increased oxygen affinity, which affects the ligand dissociation process that must precede the electron transfer process.


Sujet(s)
Cuivre/métabolisme , Hémoglobines , Consommation d'oxygène , Animaux , Sites de fixation , Monoxyde de carbone/pharmacologie , Bovins , Spectroscopie de résonance de spin électronique , N-Éthyl-maléimide/pharmacologie , Hème/analyse , Hémoglobines/métabolisme , Equus caballus/sang , Humains , Cinétique , Mercure/pharmacologie , Oxydoréduction , Lapins , Ovis , Zinc/pharmacologie
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