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1.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(12): 1936-1942, 2023 Dec 10.
Artículo en Chino | MEDLINE | ID: mdl-38129151

RESUMEN

Objective: To explore the association between hair trace element and all-cause death in the elderly in Hainan Province. Methods: The subjects of the study were elderly people from China Hainan Centenarian Cohort Study, a total of 163 elderly were included. The association between hair trace element level and all-cause death was analyzed by using Cox proportional risk regression model. Results: After fully adjusting the covariates, the multiple Cox proportional hazards regression analyses showed that selenium (Se), manganese (Mn), strontium (Sr) concentrations in hair were significantly associated with all-cause mortality, the hazard ratio (HR) were 0.72 (95%CI: 0.54-0.98, P=0.035), 1.50 (95%CI: 1.07-2.11, P=0.020) and 0.54 (95%CI: 0.37-0.79, P=0.001), respectively. Subgroup and cross analysis showed that hair copper (Cu) were significant association with death in the people with anemia, the HR were 1.81 (95%CI: 1.13-2.88, P=0.013). And, hair Mn interacted with anemia, the HR was 0.46 (95%CI: 0.22-0.94, P=0.033). Conclusions: Se, Mn and Sr concentrations in hair were associated with the elevated risk for all-cause death in the elderly in Hainan. Se, Mn and Sr concentrations in hair can be used as a reference index for the prediction of the death risk of long-lived elderly in community, suggesting that the daily diet of elderly people are rich and diverse, in order to maintain normal and balanced trace element content in the body.


Asunto(s)
Anemia , Selenio , Oligoelementos , Anciano de 80 o más Años , Humanos , Anciano , Oligoelementos/análisis , Estudios de Cohortes , Cobre , Manganeso , Cabello/química
2.
Zhonghua Bing Li Xue Za Zhi ; 52(5): 486-491, 2023 May 08.
Artículo en Chino | MEDLINE | ID: mdl-37106291

RESUMEN

Objective: To investigate the clinical and pathologic characteristics of obese adults with nonalcoholic fatty liver disease (NAFLD) and to aid the diagnosis of nonalcoholic steatohepatitis (NASH). Methods: A total of 262 patients eligible for inclusion who received volume reduction metabolism surgery and liver biopsy in the First Affiliated Hospital of Nanjing Medical University from June 2018 to September 2019 were selected. HE staining, reticular fiber staining and Masson staining were performed. Statistical analysis was performed using SPSS 20.0. Results: The patients ranged in age from 18 to 66 years. Among the 262 cases, 65 cases (65/262, 24.8%) were male and 197 cases (197/262, 75.2%) were female. Sixty-one cases (61/262, 23.3%) were non-NAFLD, 201 cases (201/262, 76.7%) were NAFLD including 27 cases (27/201, 13.4%) of nonalcoholic fatty live (NAFL) and 174 cases (174/201, 86.6%) of NASH. The main lesions of NAFLD were in hepatic acinus zone 3. There were significant differences in age, alanine aminotransferase (ALT), glutamic oxaloacetic transaminase (AST), body mass index (BMI), fasting blood-glucose (FPG) and apolipoprotein A (APOA) levels among the non-NAFLD group, NAFL group and NASH group (P<0.05). Patients with BMI≥35 m/kg2 combined with type 2 diabetes had a higher prevalence of NASH. Multiple logistic regression showed that ALT and APOA were independent predictors of NASH (P<0.001, OR=1.05, 95%CI: 1.020-1.082; P=0.027, OR=0.916, 95%CI: 0.878-0.941). Total cholesterol (CHO) and high-density lipoprotein (HDL) were independent predictors of lobular inflammation (P=0.043, 95%CI: 0.010-0.634; P=0.024, 95%CI:-3.068--0.216). AST and HDL were independent predictors of fibrosis stage (P=0.029, 95%CI: 0.001-0.021; P<0.001, 95%CI:-2.670--0.645). Conclusions: Biochemical indicators of NAFLD are closely related to its pathology. The histological lesions of NAFLD are mainly present in hepatic acinar area 3. The diagnosis of NASH is supported by extensive steatosis and high levels of CHO, ALT, AST and BMI, low levels of HDL and ApoA in biochemical markers, but pathological examination is still the gold standard for it.


Asunto(s)
Diabetes Mellitus Tipo 2 , Enfermedad del Hígado Graso no Alcohólico , Adulto , Humanos , Masculino , Femenino , Adolescente , Adulto Joven , Persona de Mediana Edad , Anciano , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patología , Hígado/patología , Obesidad/complicaciones , Obesidad/metabolismo , Obesidad/patología , Apolipoproteínas A
4.
Materials (Basel) ; 15(23)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36500062

RESUMEN

Coalbed methane (CBM) exploitation leads to permanent stress redistributions in the coal bodies connected with fracturing processes and permeability changes due to deformation induced internal pore-fracture networks. Gas permeability evolution of coal samples is investigated with a newly developed three-dimensional fluid-mechanical coupled experimental system. X-ray CT is used to investigate the internal structure of the coal samples and delivers the basis to set-up numerical twins. The work focuses on coal samples with inclusions. A novel coupling procedure between two different tools-discontinuum and continuum codes-is established to simulate the permeability evolution. The permeability is related to the crack pattern in general, and crack width in particular. A prediction of permeability is proposed based on fracture distribution and microcrack behavior. The experimental studies validated the coupling approach. Shear fractures cause substantial permeability enhancement. Piecewise relations between permeability and volumetric strain can be used to fit the whole process, where a nonlinear exponential relation is established after the expansion point. The inclusions as important structural characteristics influence this relation significantly.

5.
Eur Rev Med Pharmacol Sci ; 26(16): 5939-5945, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-36066170

RESUMEN

OBJECTIVE: The effects of intravitreal ranibizumab (IVR) as a pretreatment for vitrectomy in proliferative diabetic retinopathy (PDR) need further study. The aim of this study is to further analyze this topic. PATIENTS AND METHODS: The study group (n=26) was treated with IVR, while the control group (n=28) was not. The best corrected visual acuity (BCVA) at different time points within each group was compared. Operation time, intraoperative bleeding, silicone oil usage, iatrogenic retinal rupture and complications were compared between the groups. RESULTS: BCVA at the 1st month after vitrectomy was significantly improved in the study group (t=2.081, p=0.047) but not in the control group (I=0.164, p=0.871). At the 1st month after vitrectomy, the BCVA of the study group was significantly higher than that of the control group (t=2.1467, p=0.0365). At the 6th month after vitrectomy, the BCVA of the study group was significantly higher than that of the control group (t=2.0424, p=0.0462). The operation time in the study group was significantly shorter than that in the control group (W=2.212, p<0.05). The rates of mild and severe intraoperative bleeding in the study group were significantly lower than those in the control group (p<0.05, respectively). There was no significant difference in complications between the two groups (p>0.05). CONCLUSIONS: IVR before vitrectomy in patients with PDR can significantly improve BCVA in the early stage, improve BCVA at the 6th month after the operation, reduce the operation time and reduce intraoperative bleeding.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Inhibidores de la Angiogénesis/uso terapéutico , Diabetes Mellitus/tratamiento farmacológico , Retinopatía Diabética/tratamiento farmacológico , Retinopatía Diabética/cirugía , Humanos , Inyecciones Intravítreas , Ranibizumab/uso terapéutico , Estudios Retrospectivos , Resultado del Tratamiento , Vitrectomía
7.
Zhonghua Yu Fang Yi Xue Za Zhi ; 55(7): 867-874, 2021 Jul 06.
Artículo en Chino | MEDLINE | ID: mdl-34304424

RESUMEN

Objective: To investigate the characteristics of cervical microbiota in patients with HPV (Human Papillomavirus) infection, and to analyze the associations of cervical microbiota and HPV infection or cervicitis. Methods: 300 samples underwent HPV nucleic acid testing was collected in this case-control study from June 2019 to April 2020 in the Zhujiang Hospital of Southern Medical University, there were 150 cases allocated in HPV infection group (HPV+), and 150 cases of negative nucleic acid test were non-infectious Group (HPV-). Next-generation sequencing was used to sequence the V4 region of the bacterial 16S rRNA gene, and QIIME pipeline was used to analysis the microbiota composition of the two groups. Wilcoxon rank sum test and Kruskal-Wallis test were used to statistically analysis the differences of the microbiota between groups; and the α diversity and ß diversity of the flora between groups were statistically analyzed by Adonis multivariate analysis of variance and Wilcoxon rank sum test. Results: A total of 300 samples were analyzed in this study, of which 150 samples were HPV-positive and 150 samples were HPV-negative; among HPV-positive cases, 132 were infected by high-risk HPV (88.0%), and 18 were low-risk HPV infections (12.0%). The composition of the cervical microbiota were significantly different between the HPV+group and the HPV-group, which in the HPV+group, the α diversity of the cervical microbiota were significantly increased (Shannon index, W=8 174, P<0.000 1; PD whole tree, W=8 887, P=0.001 7). The ß diversity of the two groups was significantly different (Binary Jaccard, F=2.325 4, P=0.042 0; Bray Curtis, F=2.136 44, P=0.044 0). The relative abundance of Lactobacillus spp. and L.iners in the HPV+group sample decreased significantly (W=7 730, P<0.000 1; W=8 979, P=0.002 5), accompanied by enriched Achromobacter, Stenotrophomonas, Methylobacterium, Sneathia and Dialister. There was no significant difference in the composition of the cervical microbiota between high-risk HPV infection and low-risk HPV infection (F=4.100 4, P>0.05). In addition, cervicitis is significantly related to HPV infection (χ²=19.78, P<0.000 1), the composition of cervical flora has similarity features in cervicitis and HPV infection samples. Compared with the normal group, the cervical microbiota of cervicitis with HPV infection is mainly enriched in Achromobacter, Aerococcaceae, Streptococcus, Fusobacteria, and Xanthomonadaceae. Conclusion: The cervical microbiota of patients with HPV infection has a significant dysbiosis, with increased diversity and significant depletion of lactobacillus, accompanied by an increase in the abundance of pathogenic bacteria such as Achromobacter.


Asunto(s)
Microbiota , Infecciones por Papillomavirus , Estudios de Casos y Controles , Femenino , Humanos , Papillomaviridae/genética , ARN Ribosómico 16S/genética , Vagina
8.
Acta Endocrinol (Buchar) ; 16(2): 262, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33029247
10.
Eur J Clin Nutr ; 71(1): 9-20, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27623982

RESUMEN

BACKGROUND/OBJECTIVES: This systematic review and meta-analysis was performed to assess the effects of inulin-type fructans (ITF) on human blood lipids and glucose homeostasis associated with metabolic abnormalities, including dyslipidemia, overweight or obesity, and type-2 diabetes mellitus (T2DM). SUBJECTS/METHODS: The MEDLINE, EMBASE and Cochrane Library databases were systematically searched for randomized controlled trials (RCTs) before January 2016. Human trials that investigated the effects of ITF supplementation on the lipid profile, fasting glucose and insulin were included using Review Manager 5.3. RESULTS: Twenty RCTs with 607 adult participants were included in this systematic review and meta-analysis. In the overall analysis, the supplementation of ITF reduced only the low density lipoprotein-cholesterol (LDL-c) (mean difference (MD): -0.15; 95% confidence interval (CI): -0.29, -0.02; P=0.03) without affecting the other endpoints. Within the T2DM subgroup analysis, ITF supplementation was positively associated with a decreased fasting insulin concentration (MD: -4.01; 95% CI: -5.92, -2.09; P<0.0001) and increased high density lipoprotein-cholesterol (HDL-c) (MD: 0.07; 95% CI: 0, 0.14; P=0.05). Moreover, a reduced fasting glucose tendency was identified only in the T2DM subgroup (MD: -0.42; 95% CI: -0.90, 0.06; P=0.09). There was a potential publication bias, and few trials were available for the T2DM subgroup analysis. CONCLUSIONS: In summary, the use of ITF may have benefits for LDL-c reduction across all study populations, whereas HDL-c improvement and glucose control were demonstrated only in the T2DM subgroup. Thus, additional, well-powered, long-term, randomized clinical trials are required for a definitive conclusion. Overall, ITF supplementation may provide a novel direction for improving the lipid profile and glucose metabolism.


Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Suplementos Dietéticos , Dislipidemias/sangre , Fructanos/farmacología , Inulina/farmacología , Sobrepeso/sangre , Adulto , Glucemia/análisis , Ayuno/sangre , Femenino , Fructanos/administración & dosificación , Humanos , Insulina/sangre , Inulina/administración & dosificación , Lipoproteínas HDL/sangre , Lipoproteínas LDL/sangre , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto
11.
Eur Rev Med Pharmacol Sci ; 20(17): 3642-7, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27649665

RESUMEN

OBJECTIVE: Growth hormone deficiency (GHD) is the most common cause for childhood dwarfism. Currently, the significance of insulin-like growth factor-1 (IGF-1) in diagnosis of GHD is still debatable. Due to the possible correlation between leptin (LEP) and GHD pathogenesis, this study investigated the gene polymorphism of LEP and its receptor (LEPR) genes, along with serum IGF-1 and LEP levels in GHD patients. This study attempted to illustrate the correlation between gene polymorphism and GHD pathogenesis. PATIENTS AND METHODS: A case-control study was performed using 180 GHD children in addition to 160 healthy controls. PCR-DNA sequencing method was employed for genotyping various polymorphism loci of LEP and LEPR genes in both GHD and healthy individuals. Serum IGF-1 and LEP levels were also determined. RESULTS: Results revealed a statistically significant difference between the levels of IGF-1 and LEP in the serum samples collected from patients in the GHD and the control groups. Both IGF-1 and LEP levels were found to be correlated with polymorphism at rs7799039 loci of LEP gene, in which GG and GA genotypes carriers had higher serum IGF-1 levels when compared to AA genotype carriers. CONCLUSIONS: GHD pathogenesis is well correlated with the LEP and IGF-1 levels in the both of which were mediated by the gene polymorphism at rs7799039 loci of LEP gene.


Asunto(s)
Hormona del Crecimiento/deficiencia , Factor I del Crecimiento Similar a la Insulina/genética , Leptina/sangre , Receptores de Leptina/genética , Estudios de Casos y Controles , Niño , Femenino , Genotipo , Hormona de Crecimiento Humana , Humanos , Masculino
12.
Eur J Clin Microbiol Infect Dis ; 33(5): 853-60, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24306098

RESUMEN

One hundred and thirty-six bla OXA-51-negative strains were identified from 1,067 Acinetobacter calcoaceticus-A. baumannii complex (ACB complex) isolates, which were collected during October 2010 to March 2013 from 15 general hospitals in 10 cities throughout Zhejiang Province, China. Seven of the 136 bla OXA-51-negative ACB complex isolates were New Delhi metallo-ß-lactamase-1 (NDM-1)-positive, among which three were identified as A. nosocomialis and four were identified as A. pittii strains using 16S-23S rRNA gene intergenic spacer (ITS) sequencing and partial RNA polymerase ß-subunit (rpoB) sequencing. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) analysis showed that the seven NDM-positive isolates belonged to three clonal strains with three novel sequence types (STs). Polymerase chain reaction (PCR) assays and DNA sequence analysis of the carbapenemase and other ß-lactamase genes indicated that all the isolates harbored the bla NDM-1 gene, and that only one strain of A. nosocomialis isolates harbored both bla NDM-1 and bla OXA-23. All of them were positive for bla ADC, from which three novel bla ADC genes (designated as bla ADC-69, bla ADC-70, and bla ADC-71) were detected for the first time. The presence of ISAba125 upstream of bla NDM-1 was identified through genetic environment analysis. Carbapenem resistance can be transferred from A. nosocomialis and A. pittii to Escherichia coli EC600 by the conjugation experiment. Plasmid analysis, DNA hybridization, and extraction experiments indicated that bla NDM-1 was located on a plasmid of approximately 50 kb. In conclusion, we characterized the dissemination of NDM-1-positive A. pittii strains in Zhejiang Province, China, and reported the NDM-producing A. nosocomialis for the first time.


Asunto(s)
Infecciones por Acinetobacter/microbiología , Acinetobacter/enzimología , Acinetobacter/aislamiento & purificación , beta-Lactamasas/metabolismo , Acinetobacter/clasificación , Acinetobacter/genética , Adulto , Anciano , Anciano de 80 o más Años , China , Análisis por Conglomerados , Conjugación Genética , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Intergénico/química , ADN Intergénico/genética , ARN Polimerasas Dirigidas por ADN , Electroforesis en Gel de Campo Pulsado , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Femenino , Transferencia de Gen Horizontal , Hospitales , Humanos , Masculino , Datos de Secuencia Molecular , Tipificación Molecular , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , beta-Lactamasas/genética
13.
Chemosphere ; 65(11): 2289-96, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16806399

RESUMEN

The PAH metabolites produced during degradation of fluorene, phenanthrene and pyrene by a bacterial consortium enriched from mangrove sediments were analyzed using the on-fiber silylation solid-phase microextraction (SPME) combining with gas chromatography-mass spectrometry (GC-MS) method. Seventeen metabolites at trace levels were identified in different PAH degradation cultures based on the full scan mass spectra. In fluorene degradation cultures, 1-, 2-, 3- and 9-hydroxyfluorene, fluorenone, and phthalic acid were detected. In phenanthrene and pyrene degradation cultures, various common metabolites such as phenanthrene and pyrene dihydrodiols, mono-hydroxy phenanthrene, dihydroxy pyrene, lactone and 4-hydroxyphenanthrene, methyl ester, and phthalic acid were found. The detection of various common and novel metabolites demonstrates that SPME combining with GC-MS is a quick and convenient method for identification as well as monitoring the real time changes of metabolite concentrations throughout the degradation processes. The knowledge of PAH metabolic pathways and kinetics within indigenous bacterial consortium enriched from mangrove sediments contributes to enhance the bioremediation efficiency of PAH in real environment.


Asunto(s)
Bacterias/metabolismo , Sedimentos Geológicos/microbiología , Compuestos Policíclicos/metabolismo , Rhizophoraceae , Microbiología del Agua , Cromatografía de Gases y Espectrometría de Masas
14.
Mar Pollut Bull ; 51(8-12): 1054-61, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16291206

RESUMEN

Surface sediment samples were collected from seven mangrove swamps in Hong Kong SAR with different degrees of contamination. The total concentrations of 16 PAHs in these sediments ranged from 169.41 to 1058.37 ng g(-1) with the highest concentration found in Ma Wan and the lowest in Kei Ling Ha Lo Wai mangrove swamp. In each swamp, three bacterial consortia were enriched from sediments using phenanthrene (Phe) as the sole carbon and energy source, and individual bacterial colony showing Phe degradation was isolated and identified by 16S rDNA gene sequence. The consortia enriched from Sai Keng and Ho Chung sediments had highest ability to degrade mixed PAHs in liquid medium, with 90% Phe and Fla (fluoranthene) degraded in 7 days. On the other hand, Kei Ling Ha Lo Wai-enriched consortia degraded less than 40% Phe and Fla. Pyrene (Pyr) was hardly degraded by the consortia enriched from sediments. Bacterial isolates, namely Rhodococcus (HCCS), Sphingomonas (MWFG) and Paracoccus (SPNT) were capable to degrade mixed PAHs (Phe + Fla + Pyr). Their degradation percentages could be lower, comparable or even higher than their respective enriched consortia, depending on the consortium and the type of PAH compounds. These results suggest that PAH-degrading bacteria enriched from mangrove sediments, either as a mixed culture or as a single isolate could be used for PAHs bioremediation.


Asunto(s)
Bacterias/genética , Bacterias/metabolismo , Contaminantes Ambientales/metabolismo , Sedimentos Geológicos/microbiología , Hidrocarburos Policíclicos Aromáticos/metabolismo , Biodegradación Ambiental , Cromatografía de Gases , Sedimentos Geológicos/análisis , Hong Kong , ARN Ribosómico 16S/genética , Rhizophoraceae
15.
Rheumatology (Oxford) ; 43(5): 555-68, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15026580

RESUMEN

OBJECTIVE: To demonstrate the roles of p16(INK4a) in the senescence of human chondrocytes and the progression of osteoarthritis (OA). METHODS: Immunohistochemistry and reverse transcriptase polymerase chain reaction (RT-PCR) were performed to examine p16(INK4a) expression in fetal, normal age-matched and OA cartilage, and Western blot was used in primary cultured chondrocytes from different origins. To explore a functional p16(INK4a) knockdown in OA chondrocytes, the primary cultured cells were treated with p16(INK4a)-specific small interfering ribonucleic acids (siRNAs). Expression of p16(INK4a), p14(ARF) and p53 was observed by Western blot and RT-PCR. The phosphorylation status of pRb, senescence-associated beta-galactosidase (SA-beta-gal), cell G1/S transition and cell proliferation were studied by Western blot, histological staining, 3H-thymidine incorporation and cell counts respectively. Expression of the collagen I, collagen II and aggrecan genes was measured by semiquantitative RT-PCR. To establish the response of chondrocytes to cytokines, cells were treated with transforming growth factor-beta1 (TGF-beta1) or interleukin-1alpha (IL-1alpha) and examined for incorporation of 3H-thymidine, 3H-proline and 35S-sulphate respectively. RESULTS: A significant increase of p16(INK4a) was detected in OA chondrocytes compared with normal age-matched and fetal chondrocytes (P<0.01) in vivo and in vitro. Treated with p16(INK4a)-specific siRNAs, OA chondrocytes displayed a significant decrease in p16(INK4a) expression with an increase of phosphorylated pRb, but no alteration of p14(ARF) and p53 expression, followed by decreases of senescent features and increases in the expression of some chondrocyte-specific genes and overall repair capacity. CONCLUSIONS: p16(INK4a) is instrumental in the senescence of human articular chondrocytes or OA. The reduction of p16(INK4a) by RNA interference (RNAi) contributed to the recovery of osteoarthritic chondrocytes, suggesting that p16(INK4a) may be a viable future therapeutic candidate.


Asunto(s)
Condrocitos/fisiología , Inhibidor p16 de la Quinasa Dependiente de Ciclina/fisiología , Osteoartritis de la Rodilla/patología , Anciano , Anciano de 80 o más Años , Cartílago Articular/metabolismo , Cartílago Articular/patología , Células Cultivadas , Senescencia Celular/fisiología , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Citocinas/farmacología , Progresión de la Enfermedad , Regulación de la Expresión Génica , Humanos , Persona de Mediana Edad , Osteoartritis de la Rodilla/metabolismo , ARN Interferente Pequeño/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección , Proteína p14ARF Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/metabolismo
16.
Int J Biochem Cell Biol ; 33(11): 1064-70, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11551822

RESUMEN

The mechanism of inhibition of creatine kinase (CK) by acrylamide (Acr) has been examined (in vitro). Within the concentration range of 0 to 1 M, Acr markedly inhibited CK and depleted the protein thiols. Both inactivation and thiol depletion were time- and Acr concentration-dependent. Addition of dithiothreitol (DTT) did not reactivate CK inactivated by Acr. However, CK with 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB) pre-blocked thiols can be reactivated by DTT after incubation with Acr. The transition-state analogue also had a significant protective effect on CK against Acr inhibition. We conclude that thiol alkylation is a critical event in inactivation of CK by Acr. Furthermore, Acr binding to CK changed its surface charge, which may be the same effect for the toxicity of Acr towards other proteins.


Asunto(s)
Acrilamida/farmacología , Creatina Quinasa/antagonistas & inhibidores , Creatina Quinasa/metabolismo , Isoenzimas/antagonistas & inhibidores , Isoenzimas/metabolismo , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/enzimología , Animales , Forma MM de la Creatina-Quinasa , Ácido Ditionitrobenzoico/farmacología , Electroforesis en Gel de Poliacrilamida , Cinética , Conformación Proteica/efectos de los fármacos , Conejos , Electricidad Estática , Compuestos de Sulfhidrilo/metabolismo
17.
Am J Phys Anthropol ; 114(2): 156-62, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11169905

RESUMEN

Three digestion trials were conducted to quantify aspects of digestive physiology in the Yunnan snub-nosed monkey Rhinopithecus bieti, a foregut fermenter that feeds primarily on lichens. Mean retention time (MRT, the average time plastic markers spent in the animal) had a mean estimate of 47 hr (n = 3) with high variability between trials (standard deviation = 17 hr). Recently captured animals, presumably with gut flora and digestive physiology close to wild animals, had a longer retention time than did long-term captives, although lack of standardization across trials (such as in activity level) confounds analysis. Apparent digestibilities for dry matter (71-80%) were in line with other studies of colobine digestion, but fall below those of ruminant ungulates feeding on lichens. Fecal analysis accurately determined the relative proportions of leaves vs. lichens in diets; mature leaves and lichens were not nutritional equivalents but appeared to be physiological equivalents in terms of digest passage. Fecal analysis does not, however, accurately determine the relative proportions of food types with different digestibilities, such as fruit vs. leaves.


Asunto(s)
Colobinae/fisiología , Fenómenos Fisiológicos del Sistema Digestivo , Plantas Comestibles , Animales , Animales Salvajes , Dieta , Heces/química , Femenino , Fermentación , Líquenes , Masculino , Sensibilidad y Especificidad
18.
Phytochemistry ; 55(3): 191-5, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11142841

RESUMEN

Peaches (Prunus persica cv. Hermoza) were stored at 0C in regular air (RA) or in controlled atmosphere (CA 10% CO2, 3% O2) for 4 weeks and then ripened for 4 days at 20 degrees C. Woolliness developed in the regular air stored fruit while the controlled atmosphere stored fruit ripened normally. In the woolly fruit symptoms of the disorder were greater in the inner mesocarp than in the outer. Polygalacturonase (PG) and pectin esterase (PE) activities differed in the outer and inner mesocarp of the affected fruit. PG activity was low and PE activity was high in the inner mesocarp of the woolly fruit during ripening relative to the outer mesocarp, while in the healthy fruit, activities were similar in both areas. Cell wall fractions of water-soluble, CDTA-soluble and carbonate-soluble pectins were prepared from freshly harvested peaches and incubated with PE and PG from ripe peaches at different ratios. Only the CDTA-soluble fraction formed a gel with peach enzymes, and the rate of gelation increased with increasing amounts of PE relative to PG. Both water-soluble and CDTA-soluble pectin fractions formed gels with commercial PE (extracted from orange peel). The PE extracted from peaches was stable when stored at 0 degrees C for 9 days, while PG activity was stable only for 1 day. We suggest that PE, acting on pectins in the cell wall in vivo may cause gel formation and that the CDTA-soluble polymers have the capacity to bind apoplastic water and create the dry appearance observed in woolly fruit.


Asunto(s)
Hidrolasas de Éster Carboxílico/metabolismo , Pectinas/metabolismo , Poligalacturonasa/metabolismo , Rosales/enzimología , Geles , Rosales/química
19.
Zhongguo Yao Li Xue Bao ; 13(2): 180-2, 1992 Mar.
Artículo en Chino | MEDLINE | ID: mdl-1598837

RESUMEN

The concentration (c)-time (t) curves of piroxicam showed double peaks following iv 10 mg dose to 4 rabbits. A new mathematical model of enterohepatic circulation was proposed to explain this double-peak phenomenon and showed good agreement with data. This model provides not only the common pharmacokinetic parameters: T1/2 = 1.12 +/- 0.32 h, V1 = 0.64 +/- 0.12 L, AUC = 34.7 +/- 7.8 micrograms.h-1.ml-1, but also the parameters of enterohepatic circulation of piroxicam: the cycling amount of drug Db = 3.9 +/- 1.4 mg, reabsorption fraction Fb = 0.50 +/- 0.04, reabsorption rate constant Ka = 2.55 +/- 0.50 h-1. It is indicated in this study that enterohepatic circulation results in a 20% average increase of the effective amount of piroxicam.


Asunto(s)
Circulación Enterohepática , Piroxicam/farmacocinética , Animales , Matemática , Conejos
20.
Zhongguo Yao Li Xue Bao ; 11(1): 85-8, 1990 Jan.
Artículo en Chino | MEDLINE | ID: mdl-2403022

RESUMEN

The microcomputer program, PKP-ME (population kinetic program for Michaelis-Menten elimination), is presented to estimating population pharmacokinetic parameters of drug obeying Michaelis-Menten kinetics and predicting individual pharmacokinetic parameters. A data set consisting of 69 steady-state phenytoin concentration-dosage pairs from 44 out-patients was analyzed with the present program. Five population kinetic parameters and their standard deviations were given by PKPME. The capability predicting individual phenytoin dosage was assessed by the retrospective analysis of data of 44 patients and the prospective analysis of 15 patients. A good correlation existed between predicting dose and actual dose. Population correlation coefficient was equal to 0.99 at P = 0.05.


Asunto(s)
Fenitoína/farmacocinética , Programas Informáticos , Epilepsia/sangre , Humanos
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