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1.
Zhonghua Bing Li Xue Za Zhi ; 53(4): 351-357, 2024 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-38556818

RESUMO

Objective: To investigate the clinicopathological and molecular genetic characteristics of Crohn's disease (CD). Methods: A retrospective analysis was conducted on 52 CD patients who underwent surgical resection at the First Affiliated Hospital of Nanjing Medical University between January 2014 and June 2023. Clinical presentations and histopathological features were assessed. Whole-genome sequencing was performed on 17 of the samples, followed by sequencing and pathway enrichment analyses. Immunohistochemistry was used to assess the expression of frequently mutated genes. Results: Among the 52 patients, 34 were males and 18 were females, male-to-female ratio was 1.9∶1.0, with a median age of 45 years at surgery and 35 years at diagnosis. According to the Montreal classification, A3 (51.9%,27/52), B2 (61.5%, 32/52), and L3 (50.0%,26/52) subtypes were the most predominant. Abdominal pain and diarrhea were the common symptoms. Histopathological features seen in all 52 patients included transmural inflammation, disruption of cryptal architecture, lymphoplasmacytic infiltration, varying degrees of submucosal fibrosis and thickening, increased enteric nerve fibers and neuronal proliferation. Mucosal defects, fissure ulcers, abscesses, pseudopolyps, and adenomatous proliferation were also observed in 51 (98.1%), 38 (73.1%), 28 (53.8%), 45 (86.5%), and 28 (53.8%) cases, respectively. Thirty-one (59.6%) cases had non-caseating granulomas, and 3 (5.8%) cases had intestinal mucosal glandular epithelial dysplasia. Molecular analysis showed that 12/17 CD patients exhibited mutations in at least one mucin family gene (MUC2, MUC3A, MUC4, MUC6, MUC12, MUC17), and MUC4 was the most frequently mutated in 7/17 of cases. Immunohistochemical stains showed reduced MUC4 expression in epithelial cells, with increased MUC4 expression in the epithelial surface, particularly around areas of inflammatory cell aggregation; and minimal expression in the lower half of the epithelium. Conclusions: CD exhibits diverse clinical and pathological features, necessitating a comprehensive multidimensional analysis for diagnosis. Mutations and expression alterations in mucin family genes, particularly MUC4, may play crucial roles in the pathogenesis of CD.


Assuntos
Doença de Crohn , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Doença de Crohn/genética , Doença de Crohn/diagnóstico , Doença de Crohn/patologia , Estudos Retrospectivos , Mucinas , Células Epiteliais/patologia , Biologia Molecular
2.
Br Poult Sci ; 65(3): 352-360, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38466183

RESUMO

1. The objective of this study was to investigate the protective effects of a peptidoglycan produced by Limosilactobacillus reuteri against aflatoxin B1 (AFB1) induced toxicity in vitro and in vivo in broiler chicks.2. Toxin adsorption experiments were carried out firstly in vitro. These experiments indicated that the absorption efficiency of the peptidoglycan for AFB1 was 64.3-75.9%.3. In the in vivo experiments, Hy-Line Brown chicks were fed a diet containing AFB1 at 71.43 µg/kg with and without peptidoglycan supplementation at concentrations of 100, 200, or 300 g/kg feed from 0-42 d of age.4. The peptidoglycan supplementation in AFB1-contaminated diets resulted in significant improvements in terms of average daily gain, feed intake, feed conversion ratio, white blood cell count, haemoglobin content, glutathione peroxidase activity, immunoglobulin (Ig) A, IgG, IgM and Newcastle disease virus antibody titres (p < 0.05) and diminished liver steatosis.5. In conclusion, peptidoglycan supplementation alleviated AFB1-induced toxicity through adsorbing toxins and improving growth performance, antioxidant ability, immunity and liver pathological changes in chicks. The optimal supplemental dose was 200 mg/kg in feed.


Assuntos
Antioxidantes , Suplementos Nutricionais , Limosilactobacillus reuteri , Peptidoglicano , Peptidoglicano/administração & dosagem , Peptidoglicano/metabolismo , Peptidoglicano/uso terapêutico , Aflatoxina B1/toxicidade , Antioxidantes/administração & dosagem , Antioxidantes/metabolismo , Antioxidantes/uso terapêutico , Animais , Galinhas/crescimento & desenvolvimento , Adsorção , Ração Animal
3.
Eur Rev Med Pharmacol Sci ; 24(22): 11628-11638, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33275230

RESUMO

OBJECTIVE: Dysregulation of numerous oncogenes and their downstream signaling pathways, among others in the signaling transduction molecule p-CREB-1 (p-cAMP responsive element binding protein-1), is an essential feature of different types of cancer. To investigate whether p-CREB-1 is also pivotal in tumorigenesis and metastogenesis of breast cancer, we conducted a prospective study with long-term follow-up on 96 patients with breast cancer. PATIENTS AND METHODS: Pathway array and tissue microarray (TMA) were used to detect the differential expression of CREB (cAMP-responsive element binding protein) and p-CREB-1 in breast cancer cells, breast cancer stem cells (BCSCs), human breast cancer tissues (BCTs), and adjacent normal tissues (ANTs). The associations between p-CREB-1 expression, clinicopathological variables, and survival rates of the patients were analyzed and calculated. RESULTS: Our results revealed that p-CREB-1 and CREB expression in cancerous cell lines and tissues were significantly upregulated compared with non-cancerous cell lines and tissues. Most statistically significant overexpression was detected in BCSCs (p<0.01). In TMA and immunohistochemical analyses, BCTs exhibited significantly higher expression of p-CREB-1 and CREB than ANTs (p<0.001). Clinicopathological variable and survival analysis revealed a correlation between high expression (++/+++) of p-CREB-1 and the presence of axillary lymph node metastasis (p<0.05) and poorer disease-free and overall survival. CONCLUSIONS: p-CREB-1 is a potential predictive and prognostic biomarker and a promising therapeutic target in breast cancer.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/diagnóstico , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Serina/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Serina/metabolismo
4.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 55(11): 885-890, 2020 Nov 09.
Artigo em Chinês | MEDLINE | ID: mdl-33171563

RESUMO

Objective: To observe the changes of peri-implant tissue around the individualized abutment that was grinded from zirconia provisional crown in one year. Methods: In this research, a prosthodontic-driven virtual implant planning and immediate provisionalization were conducted in computer assisted design software. And computer-aided design/computer-aided manufacturing (CAD/CAM) techniques were used to fabricate the zirconia provisional crown and surgical guide template before surgery. The implant was accurately placed with the surgical guide, and the zirconia provisional crown was immediately delivered after surgery. Three months later, the implant osseointegration was completed, and zirconia provisional crown was prepared intraorally to generate customized zirconia abutment for final prosthesis. The study included 30 patients with single anterior tooth loss, including 18 males and 12 females, aged from 26 to 50 years old, and the mean age was (36.2±6.1) years old. The patients were from the Center of Oral Implantology, The First Affiliated Hospital of Zhejiang University Medical College from January 2017 to February 2018. After cementation of the final prosthesis, the cases were followed up at 6 and 12 months time intervals. Implant survival rate, probing depth, bleeding on probing, marginal bone level loss and papilla index score (PIS) were recorded in every appointment. Results: The survival rate of 30 implants was 100%, and the probing depths were less than 5 mm. The bone resorption at 6 and 12 months follow-up after the final delivery was 0 (0, 0) mm and 0 (-0.2, 0) mm, respectively, and the difference was not statistically significant (P>0.05). The PIS was 3.0 (2.0, 4.0), 3.0 (2.8, 4.0) and 3.0 (3.0, 4.0) on the final delivery, 6 and 12 months after final delivery, respectively. Conclusions: Marginal bone level and bone loss were stable with this new implant clinical protocol at the one-year follow-up.


Assuntos
Implantes Dentários para Um Único Dente , Implantes Dentários , Adulto , Coroas , Prótese Dentária Fixada por Implante , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Zircônio
6.
Zhonghua Fu Chan Ke Za Zhi ; 53(8): 517-521, 2018 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-30138960

RESUMO

Objective: To investigate the relationship between the level of amniotic fluid inflammatory factor and the pregnancy outcome in patients with cervical incompetence. Methods: A retrospective case-control study was conducted. Totally 110 cases of pregnant women were diagnosed as cervical incompetence for cervical dilation at the medical examination in Sun Yat-sen Memorial Hospital of Sun Yatsen University, from January 1st, 2015 to December 31th, 2016. A total of 32 patients (29.1%, 32/110) were performed cervical cerclage. According to their neonatal outcomes, they were divided into live infant group (23 cases, 72%) and dead infant group (9 cases, 28%) . The demographic and clinical data of two groups were analyzed and compared. Results: The mean peripheral blood leucocyte counts, the median amniotic tumor necrosis factor-α (TNF-α) and the median interleukin-8 (IL-8) level of two groups were (10.5±2.8) ×10(9)/L vs (13.6±3.1) ×10(9)/L, 23.80 ng/L (14.9-85.5 ng/L) vs 379.00 ng/L (70.2-418.5 ng/L) , and 3 354 ng/L (1 020-7 500 ng/L) vs 7 500 ng/L (4 210-7 500 ng/L) respectively. The differences were statistically significant (all P<0.05) . The amniotic fluid IL-1ß, IL-2 receptor, IL-6, IL-10, C-reactive protein and procalcitonin were not significantly different (all P>0.05) between two groups. Conclusions: The peripheral blood leucocyte counts, amniotic fluid TNF-α and IL-8 level are the factors affecting the pregnancy outcome in women with cervical incompetence before cervical cerclage. When IL-8 is higher than 3 580 ng/L and TNF-α is higher than 105 ng/L, the death of perinatal infants could be predicted.


Assuntos
Cerclagem Cervical , Interleucina-8 , Resultado da Gravidez , Segundo Trimestre da Gravidez/metabolismo , Incompetência do Colo do Útero/sangue , Líquido Amniótico , Proteína C-Reativa , Estudos de Casos e Controles , Feminino , Humanos , Gravidez , Estudos Retrospectivos , Fator de Necrose Tumoral alfa , Incompetência do Colo do Útero/cirurgia
7.
Cell Death Differ ; 22(4): 583-96, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25501601

RESUMO

The MT2 receptor is a principal type of G protein-coupled receptor that mainly mediates the effects of melatonin. Deficits of melatonin/MT2 signaling have been found in many neurological disorders, including Alzheimer's disease, the most common cause of dementia in the elderly, suggesting that preservation of the MT2 receptor may be beneficial to these neurological disorders. However, direct evidence linking the MT2 receptor to cognition-related synaptic plasticity remains to be established. Here, we report that the MT2 receptor, but not the MT1 receptor, is essential for axonogenesis both in vitro and in vivo. We find that axon formation is retarded in MT2 receptor knockout mice, MT2-shRNA electroporated brain slices or primary neurons treated with an MT2 receptor selective antagonist. Activation of the MT2 receptor promotes axonogenesis that is associated with an enhancement in excitatory synaptic transmission in central neurons. The signaling components downstream of the MT2 receptor consist of the Akt/GSK-3ß/CRMP-2 cascade. The MT2 receptor C-terminal motif binds to Akt directly. Either inhibition of the MT2 receptor or disruption of MT2 receptor-Akt binding reduces axonogenesis and synaptic transmission. Our data suggest that the MT2 receptor activates Akt/GSK-3ß/CRMP-2 signaling and is necessary and sufficient to mediate functional axonogenesis and synaptic formation in central neurons.


Assuntos
Axônios/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor MT2 de Melatonina/metabolismo , Transdução de Sinais , Animais , Células Cultivadas , Recuperação de Fluorescência Após Fotodegradação , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Células HEK293 , Humanos , Técnicas In Vitro , Melatonina/farmacologia , Camundongos , Camundongos Knockout , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , RNA Interferente Pequeno/metabolismo , Ratos , Receptor MT1 de Melatonina/antagonistas & inibidores , Receptor MT1 de Melatonina/genética , Receptor MT1 de Melatonina/metabolismo , Receptor MT2 de Melatonina/agonistas , Receptor MT2 de Melatonina/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Tetra-Hidronaftalenos/farmacologia
8.
Genet Mol Res ; 13(3): 5182-9, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-25061743

RESUMO

Runt-related transcription factor 3 (RUNX3) is a potential tumor suppressor that is frequently hypermethylated in hepatocellular carcinoma (HCC). The present meta-analysis of case-control studies was carried out to determine whether RUNX3 hypermethylation is associated with HCC. The PubMed, Embase, and Chinese National Knowledge Infrastructure databases were searched for all relevant studies published between May 2000 and May 2012. A total of 11 studies were identified, and 8 studies involving 491 patients with HCC and 409 patients without tumors were found to satisfy the inclusion criteria for the meta-analysis. All tissue samples were from Asian populations. There was significant heterogeneity between the studies. Over the entire sample, the odds ratio (OR) of RUNX3 promoter methylation was 18.5 [95% confidence interval (CI), 11.6-29.6] for HCC tissues relative to control tissues. The ORs of RUNX3 methylation were 16.6 (95%CI = 6.5-42.4) for tumor tissues relative to tumor-adjacent tissues in patients with HCC, 67.3 (95%CI = 13.0-348.5) for tumor tissues from patients with HCC relative to liver tissues from patients with non-neoplastic liver diseases, and 3.26 (95%CI = 1.54-6.90) for tissues from patients with hepatitis C virus (HCV)- related HCC relative to liver tissues from patients with HCC unrelated to HCV. There was no association between RUNX3 methylation and age, gender, pathological stage, or hepatitis B virus infection in HCC tissues. Methylation of the RUNX3 promoter strongly correlated with HCC in Asian populations, especially in individuals with HCV-related HCC, and may be a useful marker for HCC diagnosis in these populations.


Assuntos
Povo Asiático , Carcinoma Hepatocelular/genética , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Metilação de DNA , Hepatite C/genética , Neoplasias Hepáticas/genética , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/etnologia , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Epigênese Genética , Hepatite C/complicações , Hepatite C/etnologia , Hepatite C/patologia , Humanos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/etnologia , Neoplasias Hepáticas/patologia , Razão de Chances , Regiões Promotoras Genéticas
9.
J Clin Pharm Ther ; 39(4): 439-41, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24661191

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Drug-induced hepatotoxicity is potentially lethal. Liver transplant patients receive a large number of medications and adverse drug reactions, and drug-drug interactions must be closely monitored. CASE SUMMARY: We report a case of a 29-year-old liver transplant patient who suffered liver injury most likely induced by drug interaction between capecitabine and warfarin. Vitamin K1 caused skin rash possibly because of the distribution and metabolism characteristic of the drug in this patient. WHAT IS NEW AND CONCLUSION: Close monitoring and prompt discontinuation of the drugs with high volume of distribution and metabolized through the liver are necessary to avoid drug-drug interaction in liver transplant patients.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Transplante de Fígado/métodos , Varfarina/efeitos adversos , Adulto , Anticoagulantes/administração & dosagem , Anticoagulantes/efeitos adversos , Anticoagulantes/uso terapêutico , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/efeitos adversos , Antimetabólitos Antineoplásicos/uso terapêutico , Capecitabina , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/uso terapêutico , Toxidermias/etiologia , Toxidermias/patologia , Interações Medicamentosas , Monitoramento de Medicamentos/métodos , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Fluoruracila/uso terapêutico , Seguimentos , Humanos , Masculino , Distribuição Tecidual , Vitamina K 1/efeitos adversos , Vitamina K 1/farmacocinética , Varfarina/administração & dosagem , Varfarina/uso terapêutico
10.
Acta Virol ; 54(3): 211-5, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20822314

RESUMO

Target cells for Goose parvovirus (GPV) in natural infection are still unknown. In this study, immune system organs namely the spleen, bone marrow, thymus, bursa of Fabricius, and blood of experimentally GPV-infected goslings were examined by an immunoassay and flow cytometry for the presence of viral antigen and by a PCR for viral genome. The results indicated that the virus replicated in some cells of the spleen and bone marrow, but not in peripheral blood lymphocytes (PBLs). These data suggested that some cell populations in the spleen and bone marrow were targets for GPV infection. In addition, the immunoassay used for the detection of GPV was found comparable with a PCR in reliability and sensitivity.


Assuntos
Dependovirus/fisiologia , Sistema Imunitário/virologia , Infecções por Parvoviridae/veterinária , Doenças das Aves Domésticas/virologia , Animais , Bolsa de Fabricius/virologia , Dependovirus/genética , Dependovirus/isolamento & purificação , Gansos , Infecções por Parvoviridae/virologia , Baço/virologia , Timo/virologia
11.
Acta Virol ; 53(3): 197-202, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19941402

RESUMO

The complete genomic sequencing and characterization of Bovine viral diarrhea virus (BVDV) isolate XJ-04 originated from cattle in China was described. The genomic RNA of the isolate was 12,284 nt long and contained short 5'- untranslated region (UTR), 3'-non-coding regions (NCR), and one open reading frame (ORF) encoding a large polyprotein of 3,895 amino acids with 20 potential N-glycosylation sites. The identity of the isolate XJ-04 with reference strains NADL (BVDV-1) and 890 (BVDV-2) in autoprotease (N(pro)) gene and structural genes (C, E(rns), E1, E2) was analyzed. The percentage of nt and aa identity in analyzed genes indicated that the isolate XJ-04 was closer to the reference strain 890 (BVDV-2) than to NADL (BVDV-1). Phylogenetic analysis revealed that the isolate belonged to BVDV-2a subtype. Furthermore, comparison analysis indicated that the isolate XJ-04 did not contain any genomic insertions that can be directly related to the cytopathic phenotype.


Assuntos
Vírus da Diarreia Viral Bovina Tipo 2/genética , Regiões 5' não Traduzidas , Animais , Sequência de Bases , Bovinos , Vírus da Diarreia Viral Bovina Tipo 2/classificação , Genoma Viral , Filogenia , RNA Viral/química
12.
Acta Virol ; 53(2): 131-4, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19537915

RESUMO

The identification and characterization of bovine viral diarrhea virus 2 (BVDV-2) strain SD-06 isolated from cattle in China is reported. We performed sequence analysis of 5'-untranslated region (5'-UTR) and E2 sequences and the identity at the nucleotide and amino acid level indicated that the isolate was closely related to BVDV-2. The BVDV-2 strain New York'93 showed the highest sequence homology with the isolate SD-06. The phylogenetic analysis revealed that the isolate SD-06 belonged to BVDV-2a subtype. Furthermore, immunofluorescence assay with the monoclonal antibody specific for BVDV-2 glycoprotein E2 confirmed this identification. Thus, the strain SD-06 was the first isolate of BVDV-2 identified in China.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina , Doenças dos Bovinos , Vírus da Diarreia Viral Bovina Tipo 2/classificação , Análise de Sequência de DNA , Proteínas do Envelope Viral/genética , Regiões 5' não Traduzidas/genética , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/epidemiologia , Doença das Mucosas por Vírus da Diarreia Viral Bovina/virologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/virologia , Linhagem Celular , China/epidemiologia , Vírus da Diarreia Viral Bovina Tipo 2/genética , Vírus da Diarreia Viral Bovina Tipo 2/isolamento & purificação , Rim/citologia , Rim/virologia , Dados de Sequência Molecular , Filogenia
13.
Fertil Steril ; 71(3): 497-501, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10065788

RESUMO

OBJECTIVE: To examine potential methods for distinguishing between the acrosome reaction and acrosomal loss. DESIGN: Prospective randomized study. SETTING: Department of Obstetrics and Gynecology, Osaka University Hospital, Suita, Japan. PATIENT(S): Five healthy volunteers and 34 patients with normozoospermia who were participating in an IVF program. INTERVENTION(S): Semen samples were collected from the volunteers before the hamster egg penetration assay and from the patients at the time of IVF. MAIN OUTCOME MEASURE(S): The numbers of oocytes penetrated and spermatozoa bound were determined with the hamster egg penetration assay. Acrosomal status was assessed with two-color fluorescence staining using fluorescein isothiocyanate-conjugated Pisum sativum agglutinin (FITC-PSA) and MH61 (anti-CD46 monoclonal antibody) with Texas red-conjugated antimouse immunoglobulin G antiserum. RESULT(S): The MH61 monoclonal antibody inhibited the penetration of human spermatozoa into hamster oocytes but did not reduce the number of spermatozoa bound to the zona-free hamster oocytes. Two-color fluorescence staining revealed four staining patterns of the acrosomal region. The percentage of PSA-negative/CD46-positive spermatozoa increased to a greater extent than that of PSA-negative/CD46-negative spermatozoa with an increase in the incubation time. CONCLUSION(S): Two-color fluorescence staining with FITC-PSA and the anti-CD46 monoclonal antibody may be useful for distinguishing between the acrosome reaction and acrosomal loss.


Assuntos
Reação Acrossômica , Acrossomo/imunologia , Antígenos CD/imunologia , Corantes Fluorescentes , Lectinas/imunologia , Glicoproteínas de Membrana/imunologia , Acrossomo/ultraestrutura , Anticorpos Monoclonais , Fertilização in vitro , Fluoresceína-5-Isotiocianato , Humanos , Masculino , Proteína Cofatora de Membrana , Estudos Prospectivos , Coloração e Rotulagem
14.
Biochemistry ; 35(29): 9460-8, 1996 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-8755725

RESUMO

Chicken apocytochrome c has been shown to possess a much stronger tendency to fold spontaneously in aqueous solution than the equivalent enzyme from other species. In the present work, the amino acid that determines its folding ability was elucidated by site-directed mutagenesis. Wild-type chicken apocytochrome c and three mutants V92A, S103A, and V92A/S103A were expressed in Escherichia coli. The wild-type apoprotein and S103A exhibited the same folding property during dialysis renaturation processes as that chemically prepared from chicken cytochrome c, while those containing V92A mutation did not. Quantitative studies by 2,2,2-trifluoroethanol (TFE) and sodium perchlorate (NaClO4) titration demonstrated that the V92A mutation decreased the helix content that could be induced and confirmed that valine 92 is the major determinant of the folding propensity of chicken apocytochrome c. Furthermore, CD spectra, turbidity measurements, and a translocation assay on a model membrane system showed that the V92A mutation also drastically altered the conformation of apocytochrome c after being incorporated into lipid bilayer and decreased the aggregation of phospholipid vesicles after association of the apoprotein, thus rendering the molecule more competent for translocation across the membrane. Our results showed that a single amino acid substitution could radically alter the folding propensity of an unfolded polypeptide chain and thus influence the conformation following its insertion into phospholipid bilayer.


Assuntos
Apoproteínas/química , Apoproteínas/metabolismo , Grupo dos Citocromos c/química , Grupo dos Citocromos c/metabolismo , Fosfolipídeos/metabolismo , Dobramento de Proteína , Animais , Apoproteínas/genética , Sequência de Bases , Galinhas , Dicroísmo Circular , Grupo dos Citocromos c/genética , Citocromos c , Primers do DNA , Escherichia coli/genética , Expressão Gênica , Lipoproteínas/metabolismo , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Percloratos/farmacologia , Conformação Proteica , Desnaturação Proteica , Compostos de Sódio/farmacologia , Espectrofotometria , Titulometria , Trifluoretanol , Tripsina/metabolismo
15.
Zhongguo Yao Li Xue Bao ; 10(1): 81-4, 1989 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-2816406

RESUMO

Diethylcarbamazine citrate (DEC) at 180-300 mg/kg ip or 560 mg/kg ig inhibited hind paw swelling induced by sc 0.15 ml of carrageenan in normal and adrenalectomized rats. DEC ip 300 mg/kg also inhibited the same swelling induced by sc 2.5% formaldehyde in rats. The proliferation of granuloma induced by cotton-pellets tended to be inhibited by DEC, although not significantly. It inhibited the swelling of mouse ear induced by xylene and the increased vascular permeability induced by ip 0.7% HAC. DEC neither prolonged the survival time in adrenalectomized rats nor increased the weight of the adrenal or plasma cortisol levels in normal rats. DEC decreased the prostaglandin E content in inflammatory tissue, although less than the extent in the indomethacin group. These results indicate that the anti-inflammatory action of DEC is presumably due to the inhibition of synthesis or the release of prostaglandin E, in addition to a possible action mediated by its leukotriene synthesis inhibitor action.


Assuntos
Anti-Inflamatórios não Esteroides , Dietilcarbamazina/farmacologia , Animais , Feminino , Indometacina/farmacologia , Masculino , Camundongos , Prostaglandinas E/metabolismo , Ratos , Ratos Endogâmicos
16.
J Biol Chem ; 261(32): 14875-7, 1986 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-3533927

RESUMO

Escherichia coli strain 5C15 contains a mutation in the cca gene that decreases AMP incorporation by tRNA nucleotidyltransferase while leaving CMP incorporation unaffected. Earlier studies of the purified mutant enzyme suggested that the mutation was localized to the AMP-incorporating site. In order to analyze this mutation in more detail, the cca gene from strain 5C15 was cloned into plasmid pUC8. Analysis of tRNA nucleotidyltransferase activity in extracts of a strain transformed with this plasmid demonstrated an elevated level of CMP incorporation, but low AMP incorporation, as expected from the properties of the original mutant. Sequence analysis of the mutant cca gene revealed only a single G to A point mutation leading to a glycine to aspartic acid substitution at position 70 of the peptide chain. The amino acid change was localized to one of two Gly-X-Gly-X-X-Gly sequences present in the protein. This sequence has been identified previously near the nucleotide-binding domain of various proteins, but it has not been noted in enzymes that incorporate nucleotide residues. However, other sequences often associated with ATP-binding domains are not found in tRNA nucleotidyltransferase. The implications of these findings for our understanding of nucleotide-binding domains are discussed.


Assuntos
Monofosfato de Adenosina/metabolismo , Escherichia coli/genética , Genes Bacterianos , Genes , Mutação , RNA Nucleotidiltransferases/genética , Sequência de Aminoácidos , Sequência de Bases , Escherichia coli/enzimologia , RNA Nucleotidiltransferases/metabolismo
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