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2.
Zhonghua Yi Xue Za Zhi ; 99(12): 889-894, 2019 Mar 26.
Article de Chinois | MEDLINE | ID: mdl-30917436

RÉSUMÉ

Objective: To observe the clinicopathologic features and prognostic of patients with IgA nephropathy (IgAN) superimposed on transplant glomerulopathy (TG+ IgAN). Methods: Electronic medical records of Jinling Hospital were searched for TG+ IgAN patients that was diagnosed during January 2004 to December 2016. Clinicopathologic features and prognoses information were retrieved and analyzed. The primary outcome was initiation of replacement therapy or an eGFR declined to<15 ml·min(-1)·(1.73m(2))(-1). Results: A total of 49 patients with pathologically confirmed TG+ IgAN were enrolled in this study. The median time from renal transplantation to allograft biopsy was 85 months. There were 131 patients with TG in the control group. There was no statistical difference in the age, gender, and immunosuppressive regimen during renal biopsy in the two groups. In TG+ IgAN patients, the median serum creatinine level was 175 µmol/L, the median urinary protein was 1.45 g/24 h, and 16.3% of the patients had nephrotic range proteinuria, the incidence of microscopic hematuria was 40.8%, and the average hemoglobin was 105 g/L. In terms of pathology, the degree of glomerular mesangial matrix hyperplasia in the TG+ IgAN group was significantly heavier compared with TG group (P=0.004), and the degree of hyaline degeneration of the small arteries was lighter (P=0.043). There was no significant difference in interstitial inflammation (i), tubulitis (t), glomerulitis (g), peritubular capillaritis (ptc) and intimal arteritis (v). Calculated by Kaplan-Meier method, the median survival time of 49 patients with TG+ IgAN was 36.9 months, and there was no difference in survival rate of allografts compared with TG group. Conclusions: Compared with TG patients without IgA, TG+ IgAN patients had higher incidence of microscopic hematuria, more severe glomerular mesangial matrix hyperplasia, and no significant differences in other clinicopathological features. The prognosis of TG+ IgAN patients was not significantly different from those without IgAN.


Sujet(s)
Glomérulonéphrite à dépôts d'IgA , Biopsie , Humains , Glomérule rénal , Transplantation rénale , Pronostic , Protéinurie
3.
J Phys Condens Matter ; 30(5): 055702, 2018 02 07.
Article de Anglais | MEDLINE | ID: mdl-29324434

RÉSUMÉ

In this study, a direct sulfidation reaction of ammonium perrhenate (NH4ReO4) leading to a synthesis of rhenium disulfide (ReS2) is demonstrated. These findings reveal the first example of a simplistic bottom-up approach to the chemical synthesis of crystalline ReS2. The reaction presented here takes place at room temperature, in an ambient and solvent-free environment and without the necessity of a catalyst. The atomic composition and structure of the as-synthesized product were characterized using several analysis techniques including energy dispersive x-ray spectroscopy, x-ray photoelectron spectroscopy, x-ray diffraction, transmission electron microscopy, Raman spectroscopy, thermogravimetric analysis and differential scanning calorimetry. The results indicated the formation of a lower symmetry (1T') ReS2 with a low degree of layer stacking.

4.
Transplant Proc ; 46(10): 3383-9, 2014 Dec.
Article de Anglais | MEDLINE | ID: mdl-25498056

RÉSUMÉ

INTRODUCTION: Plasma concentration monitoring is commonly used to adjust immunosuppressant dosage in transplant recipients, but adjustment is often based on clinical experience rather than rigorous quantitative indicators. METHODS: We examined the effect of mycophenolate mofetil (MMF) dosage on graft survival by pathologic and immunologic analysis of 88 kidney recipients who were given a postoperative immunosuppressive regimen of tacrolimus (FK506), MMF, and corticosteroids. Patients were given a conventional dosage (≥1.5 g/d; n = 40) or a reduced dosage (n = 48) of MMF owing to postoperative adverse side effects. RESULTS: The reduced-dose group included patients given low doses (≤1.0 g/d; n = 27), ultra-low doses (≤0.5 g/d; n = 15), and those who discontinued MMF (n = 6). The dose reduction group had increased acute rejection, chronic rejection, and graft dysfunction, poorer pathologic scores, and increased cell infiltration of graft tissue (CD4, CD8, CD68, and CD138 positivity) and expression of interleukin-2R and HLA-DR. Finally, hazard analysis indicated that patients given low doses and ultra-low doses of MMF had poorer long-term kidney grafts survival (hazard ratios of 1.52 and 1.78, respectively). CONCLUSIONS: These results indicate the importance of using an appropriate dosage of MMF in kidney transplant recipients.


Sujet(s)
Rejet du greffon/anatomopathologie , Survie du greffon/effets des médicaments et des substances chimiques , Immunosuppresseurs/administration et posologie , Transplantation rénale , Acide mycophénolique/analogues et dérivés , Hormones corticosurrénaliennes/administration et posologie , Adulte , Biopsie , Association de médicaments , Femelle , Rejet du greffon/immunologie , Rejet du greffon/prévention et contrôle , Survie du greffon/immunologie , Humains , Rein/anatomopathologie , Mâle , Adulte d'âge moyen , Acide mycophénolique/administration et posologie , Prednisone/administration et posologie , Études rétrospectives , Tacrolimus/usage thérapeutique
5.
Transplant Proc ; 45(6): 2226-32, 2013.
Article de Anglais | MEDLINE | ID: mdl-23953533

RÉSUMÉ

OBJECTIVE: Late severe noninfectious diarrhea in renal transplant recipients can lead to malnutrition and even graft loss. The purpose of this study was to evaluate risk factors associated with this condition and summarize therapy for these patients. METHODS: For more than 36 months we observed a cohort of 541 recipients who underwent kidney transplantation from January 2001 to June 2007. They were provided a calcineurin inhibitor (CNI) combined with mycophenolate mofetil (MMF). The four group includes a continuous cyclosporine (CsA); a preconversion to tacrolimus and a postconversion group as well as a continuous tacrolimus group. The rate of severe late noninfectious diarrhea was compared among the four groups. Risk factors were analyzed between the diarrhea and nondiarrhea cohorts. Clinical characteristics, efficacy, and safety were observed after modifying the immunosuppressive protocol for late severe noninfectious diarrhea recipients. RESULTS: Twenty-eight recipients presented with late sever noninfectious diarrhea. No patients displayed chronic diarrhea in the CsA (n = 145) or preconversion group (n = 95). The rate of diarrhea was 7.31% in the postconversion and 7.35% in the tacrolimus group. Using multivariate Cox proportional hazards analysis, factors associated with an increased risk of noninfectious diarrhea were cytochrome P450(CYP)3A5 *3/*3 type, chronic renal allograft dysfunction, and patient ingestion of Tripterygium wilfordii Hook F. All diarrheal recipients experienced weight loss, hypoalbuminia, and an increased serum creatinine. All affected patients underwent adjustment of the immunosuppressive regimen to achieve remission. Renal allograft survival in recipients with diarrhea was worse than that in nondiarrheal recipients receiving tacrolimus combined with MMF. CONCLUSION: Tacrolimus with MMF increased the risk of late severe noninfectious diarrhea among renal transplant recipients compared with hosts treats with CsA plus MMF. The CYP3A5 *3/*3 type, chronic renal allograft dysfunction, and T. wilfordii supplementation were high-risk factors for late diarrhea. Prompt adjustment of immunosuppression was an effective, feasible therapy for these patients.


Sujet(s)
Diarrhée/étiologie , Immunosuppresseurs/effets indésirables , Transplantation rénale/effets indésirables , Adolescent , Adulte , Loi du khi-deux , Ciclosporine/effets indésirables , Cytochrome P-450 CYP3A/génétique , Diarrhée/diagnostic , Diarrhée/thérapie , Substitution de médicament , Femelle , Prédisposition génétique à une maladie , Humains , Estimation de Kaplan-Meier , Mâle , Adulte d'âge moyen , Analyse multifactorielle , Acide mycophénolique/effets indésirables , Acide mycophénolique/analogues et dérivés , Préparations à base de plantes/effets indésirables , Modèles des risques proportionnels , Facteurs de risque , Indice de gravité de la maladie , Tacrolimus/effets indésirables , Facteurs temps , Résultat thérapeutique , Tripterygium , Jeune adulte
6.
Transplant Proc ; 41(5): 1557-61, 2009 Jun.
Article de Anglais | MEDLINE | ID: mdl-19545678

RÉSUMÉ

OBJECTIVE: Tacrolimus concentrations are associated with CYP3A5 genotype. The purpose of this study was to evaluate the outcomes and drug concentrations/doses among a posttransplant population with various CYP3A5 genotypes within 12 months. METHODS: Sixty seven kidney recipients receiving immunosuppression with tacrolimus + mycophenolate mofetil + prednisolone were grouped according to their CYP3A5 genotypes (*1/*1; *1/*3; *3/*3). The initial dose of tacrolimus (0.15 mg/kg/d) was adjusted according to achieve a target therapeutic window. All patients underwent a protocol biopsy at 1 month posttransplantation. We assayed serum creatinine and tacrolimus blood trough concentrations to calculate the concentration per dosage during follow-up. We also investigated the incidence of acute rejection episodes and the nephrotoxicity of tacrolimus according to the renal biopsy. RESULTS: There was no significant difference among serum creatinine concentrations. Tracrolimus blood concentrations showed a significant difference at day 7 and 1 month with no significant difference at 3, 6, or 12 months among the three groups. The CYP3A5*3/*3 group showed the largest concentration per dosage (C/D) and CYP3A5*1/*1, the smallest C/D. There was a significant difference among the three groups. The occurrence of an acute rejection episode within 3 months showed a significant difference among the three groups but not from 3 to 12 months after transplantation. Nephrotoxicity was greatest among the CYP3A5*3/*3 group. CONCLUSION: CYP3A5 influenced the blood concentrations of tacrolimus. Our study suggested to choose the initial dosage according to the CYP3A5 genotype to obtain a better outcome and reduce the incidences of acute rejection episodes and nephrotoxicity.


Sujet(s)
Cytochrome P-450 CYP3A/génétique , Transplantation rénale/immunologie , Polymorphisme génétique , Tacrolimus/usage thérapeutique , Adolescent , Adulte , Cadavre , Enfant , Créatinine/sang , Association de médicaments , Femelle , Génotype , Humains , Immunosuppresseurs/sang , Immunosuppresseurs/usage thérapeutique , Transplantation rénale/anatomopathologie , Tubules rénaux/anatomopathologie , Mâle , Adulte d'âge moyen , Tacrolimus/sang , Donneurs de tissus , Transplantation homologue , Jeune adulte
7.
Transplant Proc ; 41(5): 1639-42, 2009 Jun.
Article de Anglais | MEDLINE | ID: mdl-19545698

RÉSUMÉ

OBJECTIVE: Our aim was to evaluate the prognostic effect of peripheral blood lymphocyte subgroup CD4+ and CD8+ cells on renal transplant patients with cytomegalovirus (CMV) viremia. MATERIALS AND METHODS: Using 41 renal transplant patients with CMV-PCR(+) in peripheral blood and stable values of serum creatinine (SCr), we evaluated the changes in lymphocyte subgroup CD4+ and CD8+ cells with onset of antiviral therapy with gancyclovir for treatment of pneumonia. We compared patients with or without pneumonia. RESULTS: The lower the peripheral blood lymphocyte subgroup CD4+ and CD8+ cell numbers, the higher the incidence of CMV pneumonia. The numbers of CD4+ and CD8+ cells at 1 month posttransplantation and at the time of CMV-PCR(+) detection were significantly lower than those before transplantation in the CMV pneumonia group (P < .01) and also in the nonpneumonia group. CONCLUSIONS: The decrease in peripheral blood lymphocyte subgroup CD4+ and CD8+ cells after renal transplantation in patients with CMV viremia showed prognostic value for pneumonia. Increased CD4+ and CD8+ cells in peripheral blood combined with preemptive therapy may reduce the incidence of pneumonia among patients with CMV viremia.


Sujet(s)
Lymphocytes T CD4+/immunologie , Lymphocytes T CD8+/immunologie , Infections à cytomégalovirus/étiologie , Transplantation rénale/immunologie , Adulte , Antiviraux/usage thérapeutique , Lymphocytes T CD4+/virologie , Lymphocytes T CD8+/virologie , Cytomegalovirus/génétique , Infections à cytomégalovirus/traitement médicamenteux , Infections à cytomégalovirus/immunologie , Association de médicaments , Femelle , Ganciclovir/usage thérapeutique , Humains , Immunosuppresseurs/usage thérapeutique , Transplantation rénale/effets indésirables , Numération des lymphocytes , Mâle , Adulte d'âge moyen , Pneumopathie infectieuse/épidémiologie , Pneumopathie infectieuse/prévention et contrôle , Pneumopathie virale/épidémiologie , Pneumopathie virale/immunologie , Réaction de polymérisation en chaîne , Pronostic
8.
Transplant Proc ; 40(10): 3474-8, 2008 Dec.
Article de Anglais | MEDLINE | ID: mdl-19100416

RÉSUMÉ

Sirolimus (SRL) is a potent immunosuppressive drug used to prevent acute allograft rejection after renal transplantation. Nevertheless, the occurrence of proteinuria has recently been recognized among patients on SRL-based therapy. The aim of this study was to investigate the therapeutic effects of Tripterygium wilfordii Hook F. (T II) on proteinuria associated with SRL in renal transplant recipients. According to accepting T II, 36 recipients were divided into 2 groups: T II group (n = 21) and valsartan group (n = 15). The T II group was administered 1 mg/kg/d, and the valsartan group, 80 mg twice per day for 12 months. Efficiency was then evaluated. Complete remission: proteinuria decreased by >50%; partial remission: proteinuria decreased by 20% to 50%; ineffective: proteinuria decreased by <20%. Upon 12-month follow-up, the total effective rates in the T II group and the valsartan group were 95.2% and 86.7% (P < .05), respectively. Twenty of 21 patients with proteinuria in the T II group were negative at 3-month follow-up with disappearance of edema. There were some adverse events that had greater incidence rates in the valsartan group compared with the T II group, such as hyperkalemia (26.7% vs 4.8%). We concluded that the application of T II markedly reduced proteinuria associated with SRL in renal transplant patients.


Sujet(s)
Transplantation rénale/immunologie , Extraits de plantes/usage thérapeutique , Protéinurie/traitement médicamenteux , Sirolimus/effets indésirables , Tripterygium , Adulte , Antihypertenseurs/usage thérapeutique , Chine , Femelle , Humains , Immunosuppresseurs/effets indésirables , Mâle , Adulte d'âge moyen , Acide mycophénolique/analogues et dérivés , Protéinurie/induit chimiquement , Tétrazoles/usage thérapeutique , Valine/analogues et dérivés , Valine/usage thérapeutique , Valsartan , Jeune adulte
9.
Eur J Biochem ; 267(12): 3461-8, 2000 Jun.
Article de Anglais | MEDLINE | ID: mdl-10848961

RÉSUMÉ

The role of electrostatic interactions in determining the rate of electron transfer between cytochrome f and plastocyanin has been examined in vitro with mutants of turnip cytochrome f and mutants of pea and spinach plastocyanins. Mutation of lysine residues Lys58, Lys65 and Lys187 of cytochrome f to neutral or acidic residues resulted in decreased binding constants and decreased rates of electron transfer to wild-type pea plastocyanin. Interaction of the cytochrome f mutant K187E with the pea plastocyanin mutant D51K gave a further decrease in electron transfer rate, indicating that a complementary charge pair at these positions could not compensate for the decreased overall charge on the proteins. Similar results were obtained with the interaction of the cytochrome f mutant K187E with single, double and triple mutants of residues in the acidic patches of spinach plastocyanin. These results suggest that the lysine residues of the basic patch on cytochrome f are predominantly involved in long-range electrostatic interactions with plastocyanin. However, analysis of the data using thermodynamic cycles provided evidence for the interaction of Lys187 of cytochrome f with Asp51, Asp42 and Glu43 of plastocyanin in the complex, in agreement with a structural model of a cytochrome f-plastocyanin complex determined by NMR.


Sujet(s)
Cytochromes/composition chimique , Cytochromes/métabolisme , Plastocyanine/composition chimique , Plastocyanine/métabolisme , Acide aspartique , Brassica/enzymologie , Dichroïsme circulaire , Cytochromes/génétique , Cytochromes f , Lysine , Spectroscopie par résonance magnétique , Mutagenèse dirigée , Oxydoréduction , Conformation des protéines , Spectrophotométrie UV , Électricité statique , Thermodynamique
10.
Eur J Biochem ; 267(6): 1732-42, 2000 Mar.
Article de Anglais | MEDLINE | ID: mdl-10712605

RÉSUMÉ

Soluble turnip cytochrome f has been purified from the periplasmic fraction of Escherichia coli expressing a truncated petA gene encoding the precursor protein lacking the C-terminal 33 amino-acid residues. The protein is identical [as judged by 1H-NMR spectroscopy, midpoint redox potential (+ 365 mV) and electron transfer reactions with plastocyanin] to cytochrome f purified from turnip leaves. Several residues in the hydrophobic patch surrounding the haem group have been changed by site-directed mutagenesis, and the proteins purified from E. coli. The Y1F and Q7N mutants showed only minor changes in the plastocyanin-binding constant Ka and the second-order rate constant for electron transfer to plastocyanin, whereas the Y160S mutant showed a 30% decrease in the overall rate of electron transfer caused in part by a 60% decrease in binding constant and partially compensated by an increased driving force due to a 27-mV decrease in redox potential. In contrast, the F4Y mutant showed increased rates of electron transfer which may be ascribed to an increased binding constant and a 14-mV decrease in midpoint redox potential. This indicates that subtle changes in the hydrophobic patch can influence rates of electron transfer to plastocyanin by changing the binding constants and altering the midpoint redox potential of the cytochrome haem group.


Sujet(s)
Cytochromes/composition chimique , Protéines végétales/composition chimique , Plastocyanine/métabolisme , Séquence d'acides aminés , Substitution d'acide aminé , Sites de fixation , Brassica/métabolisme , Phénomènes chimiques , Chimie physique , Dichroïsme circulaire , Cytochromes/génétique , Cytochromes/métabolisme , Cytochromes f , Transport d'électrons , Escherichia coli , Hème/composition chimique , Cinétique , Spectroscopie par résonance magnétique , Modèles moléculaires , Mutagenèse dirigée , Oxydoréduction , Protéines végétales/génétique , Protéines végétales/métabolisme , Plastocyanine/composition chimique , Plastocyanine/génétique , Conformation des protéines , Protéines de fusion recombinantes/composition chimique , Protéines de fusion recombinantes/métabolisme
11.
Shi Yan Sheng Wu Xue Bao ; 25(2): 149-55, 1992 Jun.
Article de Chinois | MEDLINE | ID: mdl-1414125

RÉSUMÉ

Changes in the contents of DNA and RNA, RNA species, the synthesis rates of DNA and RNA, and the activity of DNase and RNase were investigated in the callus of tobacco (Nicotiana tabacum L. cv. Willow Leaf) during subculture and differentiation. The contents of DNA and RNA were higher in differentiating callus than that in subcultured callus. After day 12, the contents of DNA and RNA in differentiating callus rose continuously while the contents of DNA and RNA in subcultured callus remained constant. Changes in RNA species and its relationship to total RNA level were also analyzed. At the stage of shoot primordium formation in differentiating callus, the activity of RNase increased markedly and the synthesis rate of RNA increased continuously; while the RNase activity and the synthesis rate of RNA in subcultured callus were much lower during the same period. During the period of shoot growth, the synthesis rate of DNA in differentiating callus was elevated compared to that in subcultured callus. The results above suggested that the metabolism of nucleic acids in differentiating callus was more active than that in subcultured callus.


Sujet(s)
Nicotiana/croissance et développement , Acides nucléiques/métabolisme , Plantes médicinales/croissance et développement , Végétaux toxiques , Techniques de culture/méthodes , Plantes médicinales/métabolisme , Graines , Nicotiana/métabolisme
12.
Yao Xue Xue Bao ; 25(5): 345-8, 1990.
Article de Chinois | MEDLINE | ID: mdl-2284953

RÉSUMÉ

The composition and stability constants of the host-guest inclusion complexes of beta-cyclodextrin (beta-CD) with fluorouracil (5-Fu) and ftorafur (FT-207) were studied by 19F NMR. The 19F chemical shift changes (delta) of 5-Fu and FT-207 on complexation with beta-CD were used to determine the stoichiometry of these inclusion complexes by Job plot. It was shown that both 5-Fu and FT-207 formed 1:1 inclusion complexes with beta-CD. The stability constants (Kc) of their complexes. with beta-CD, calculated from the slope of linear relation between delta/CCD0 and delta(CCD0 being the initial concentration of beta-CD) were found to be 17.0 +/- 1.7 mol-1.L and 9.0 +/- 0.1 mol-1.L at 40 degrees C respectively. The 19F chemical shifts of these complexes relative to their free forms were also obtained and discussed in terms of the structures of these beta-CD inclusion complexes in aqueous solution.


Sujet(s)
Cyclodextrines , Fluorouracil , Tégafur , Cyclodextrines bêta , Cyclodextrines/composition chimique , Vecteurs de médicaments , Association médicamenteuse , Stabilité de médicament , Spectroscopie par résonance magnétique
13.
Yao Xue Xue Bao ; 24(10): 733-6, 1989.
Article de Chinois | MEDLINE | ID: mdl-2618663

RÉSUMÉ

1H and 13C NMR spectra of d,l- and meso-HM-PAO in different solvents were studied at different resonance frequencies. The 1HNMR spectra of two diastereoisomers are the same in dimethyl sulfoxide and acetone, but different in chloroform. The 13C NMR spectra are different in dimethyl sulfoxide and chloroform. The different 1H and 13C NMR spectra can be used to identify and differentiate these two diastereoisomers. It is also shown that the d,l-HM-PAO stereoisomeric purity in a mixture of these two isomeric forms can be determined with sufficient accuracy by using 13C peak areas or heights of their C(5) and C(7) in a routine noise decoupling 13C spectrum of the mixture.


Sujet(s)
Spectroscopie par résonance magnétique , Composés organiques du technétium , Oximes , Stéréoisomérie , Examétazime de technétium (99mTc)
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