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2.
Zhonghua Liu Xing Bing Xue Za Zhi ; 39(2): 204-207, 2018 Feb 10.
Artigo em Chinês | MEDLINE | ID: mdl-29495206

RESUMO

Objective: To study the willingness and influence factors related to "centralized slaughtering, fresh poultry listing and marketing" strategy, among the household chefs, and provide reference for government to adjust and optimize the strategy on avian influenza prevention. Methods: According to the geographical characteristics and regional functions, 6 'monitoring stations' were selected from 12 residential districts of Guangzhou, respectively. Another 21 meat markets which selling live poultry, were selected in each station and 5 household chefs of each market were invited to attend a face to face interview. Basic information, personal cognitive, willingness and influencing factors to the policy were under study. Univariate and multivariate logistic regression methods were used. Results: A total of 664 household chefs underwent the survey and results showed that the rate of support to the "centralized slaughtering, fresh poultry listing and marketing" strategy was 44.6% (296/664). Results from the multi-factor logistic regression showed that those household chefs who were males (OR=1.618, 95% CI: 1.156-2.264, P=0.005), having received higher education (OR=1.814, 95% CI: 1.296-2.539, P=0.001), or believing that the existence of live poultry stalls was related to the transmission of avian influenza (OR=1.918, 95% CI: 1.341-2.743, P<0.001) were factors at higher risk. These household chefs also intended to avoid the use of live poultry stalls (OR=1.666, 95%CI: 1.203-2.309, P=0.002) and accept the "centralized slaughtering, fresh poultry listing and marketing" strategy. Conclusion: Detailed study on this subject and, setting up pilot project in some areas as well as prioritizing the education programs for household chefs seemed helpful to the implementation of the 'freezing-fresh poultry' policy.


Assuntos
Atitude Frente a Saúde , Subtipo H7N9 do Vírus da Influenza A , Influenza Humana/prevenção & controle , Marketing , Indústria de Embalagem de Carne , Aves Domésticas/virologia , Animais , China , Humanos , Influenza Aviária , Masculino , Análise Multivariada , Projetos Piloto , Inquéritos e Questionários
3.
J Nutr Health Aging ; 21(9): 943-953, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29083434

RESUMO

OBJECTIVES: The associations between nutritional status and lifestyle factors have not been well established. This study aimed to investigate the prevalence of poor nutrition and to examine the relationships between nutritional status and unhealthy lifestyle and other related factors among the elderly. METHODS: This cross-sectional study was conducted in Liaobu Town, Dongguan city, China. A total of 708 community-dwelling older adults aged ≥60 years were recruited by stratified random sampling. Data on sociodemographic characteristics, health and lifestyle factors, and the Mini Nutritional Assessment (MNA) scores were collected using structured questionnaires via face-to-face interviews. A multivariate logistic regression model was constructed to identify the risk factors of poor nutrition. RESULTS: The prevalence of malnutrition among the elderly adults in this study was 1.3%, and 24.4% were at risk of malnutrition (RM). Poor nutrition was significantly associated with female gender, older age, lower education, a high number of self-reported chronic diseases, and hospitalization in the last year. Unhealthy lifestyle factors associated with poor nutrition included current smoking status, higher alcohol consumption, lack of physical activity, longer duration of sitting, negative attitude towards life, and a poor family relationship. CONCLUSIONS: While the prevalence of malnutrition was low, RM was high in the elderly population in China. The determinants of malnutrition were explored and the relationships between nutritional status and unhealthy lifestyle factors were examined. The results of this study provide information for future longitudinal studies with multi-factorial interventional design in order to determine the effects of the causal relationships.


Assuntos
Estilo de Vida , Estado Nutricional/fisiologia , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Estudos Transversais , Feminino , Avaliação Geriátrica/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco
4.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 52(4): 254-258, 2017 Apr 09.
Artigo em Chinês | MEDLINE | ID: mdl-28412793

RESUMO

Objective: To investigate the effect of restraint stress on masseter mechanical hyperalgesia and the activity of neurons and astrocytes in the spinal trigeminal nucleus caudalis (Vc). Methods: The animals were randomly divided into the control group, 1-, 3-, 5-, 7-, 9-, 11-and 14-day stress groups, with 10 rats in each group. The body weight increase and behavior tests were used to testify the animal model. The mechanical sensitivity of masseter of the rat before and after the stress was measured with Von Frey filaments. Histological examinations were used to evaluate the expression of neuronal c-fos and astrocytic glial fibrillary acidic protein (GFAP). Results: Restraint stress resulted in remarkable mechanical allodynia in the masseter muscle. The head withdrawal threshold was significantly lower in the 7-, 9-, 11-and 14-day stress groups ([0.071±0.011], [0.059±0.020], [0.052±0.011], [0.033±0.011] N) than that in the control group ([0.120±0.025] N) (P<0.05). Compared to the control group, the rats in the 1-day stress group showed a significant increase of c-fos in neurons of the Vc and then declined to normal level after 1 week gradually. The GFAP expression in astrocytes of the Vc was significantly increased in the 7-, 9-, 11-and 14-day stress groups (4.3±1.0, 4.5±0.6, 4.6±0.5, 4.8±1.3) compared with the control group (2.0±0.8) (P<0.05). Conclusions: Chronic restraint stress could lower the threshold of mechanical allodynia in the masseter muscle and activate the neurons and astrocytes in Vc. The activation of neurons and astrocytes plays an important role in the masseter hyperalgesia induced by restraint stress in rats.


Assuntos
Astrócitos/fisiologia , Hiperalgesia/fisiopatologia , Músculo Masseter/fisiopatologia , Neurônios/fisiologia , Restrição Física/efeitos adversos , Núcleo Espinal do Trigêmeo/fisiopatologia , Animais , Astrócitos/metabolismo , Modelos Animais de Doenças , Proteína Glial Fibrilar Ácida/metabolismo , Hiperalgesia/etiologia , Masculino , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
5.
Zhonghua Yi Xue Za Zhi ; 96(20): 1573-7, 2016 May 31.
Artigo em Chinês | MEDLINE | ID: mdl-27266685

RESUMO

OBJECTIVE: To study the effect of metanephric mesenchymal stem cells (MMSCs ) after renal ischemia reperfusion injury (IRI). METHODS: C57BL/6J male mice were divided into control group (n=5) and experimental group (n=30). The control group was given a sham operation, while in the experimental group, a model of renal IRI was established. The experimental group was further divided into two groups according to the material injected through the femoral vein: IRI group (injected with normal saline, 10 ml/kg) and cell therapy group (injected with normal saline containing 5×10(5) MMSCs, 10 ml/kg). Samples of blood and kidney tissues were collected from five mice from each group at 12 h, 24 h and 72 h after IRI. The serum creatinine (SCr) level was detected, and the results of kidney tissue pathological staining and Paller score of renal tubules were analyzed to assess the effect of MMSCs after renal IRI. In addition, the expression of microRNA-26a(miR-26a)in kidney tissues was detected by reverse transcriptase-polymerase chain reaction (RT-PCR) and compared among the groups. RESULTS: (1) In both IRI group and cell therapy group, the levels of SCr at 12 h, 24 h and 72 h after operation were all significantly higher than those of the control group, besides, the level of SCr at 24 h was significantly higher than that at 12 h and 72 h (all P<0.05). The levels of SCr at 12 h, 24 h and 72 h were of no significant differences between IRI group and cell therapy group(all P>0.05). (2)Paller scores of renal tubules at 12 h, 24 h and 72 h in both IRI group and cell therapy group were significantly higher than those in the control group, and the scores at 24 h were significantly higher than that at 72 h, while the latter were in turn higher than the scores at 12 h (all P<0.05). In the cell therapy group, Paller score of renal tubules at 24 h(57.2±6.3)was significantly lower than that in IRI group(70.8±14.8) (P<0.05). Histological examination showed renal tubular epithelial cell atrophy, swelling and protein cast in kidney tissues from IRI group at 24 h, compared with the control group and the cell therapy group at the same time.(3) In IRI group and cell therapy group, the levels of miR-26a in the kidney tissues at 12 h and 24 h were significantly lower than those of the control group (P<0.05). In the cell therapy group, the level of miR-26a in the kidney tissues at 24 h (0.416±0.139) and 72 h (1.152±0.239)were significantly higher than that in the IRI group(0.244±0.067, 0.855±0.038, both P<0.05). A negative correlation between the levels of miR-26a and SCr level were found (r=-0.5, P<0.05). CONCLUSION: MMSCs have a certain repairing effect on renal IRI, accompanied by an increase in miR-26a expression.


Assuntos
Túbulos Renais/metabolismo , Rim/metabolismo , Células-Tronco Mesenquimais , Traumatismo por Reperfusão , Animais , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Rim/irrigação sanguínea , Rim/patologia , Testes de Função Renal , Túbulos Renais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética , MicroRNAs/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
6.
Zhonghua Xue Ye Xue Za Zhi ; 37(12): 1027-1032, 2016 Dec 14.
Artigo em Chinês | MEDLINE | ID: mdl-28088963

RESUMO

Objective: To analyze the clinical characteristics and prognosis of adult T cell leukemia/lymphoma (ATLL). Methods: Peripheral blood samples from patients who were suspected as ATLL from March, 2013 to July, 2015, were collected for HTLV-1 provirus genes detection in genomic DNA extraction by PCR. Cases showing positive results were confirmed as ATLL. Clinical and laboratory characteristics, therapeutic outcomes and survival evaluation were collected. Results: 12 out of 23 suspected patients were confirmedly diagnosed as ATLL through HTLV-1 provirus genes detection by PCR. Eight patients were male and four patients were female. Median age was 51 (range 28-66) years old. All of those patients came from coastal cities of Fujian province where a HTLV-1 epidemic area locates. In the subtype classification of these 12 ATLL, 11 patients were classified as acute type and one case as lymphoma type ATLL. As one of the clinical characteristics of ATLL, ' flower cells ', with typical or atypical morphology had been observed in a high rate (81.8%). Clinical symptom such as hepatomegaly, splenomegaly and lymphadenectasis were detected in most of patients, and hypercalcemia and elevated LDH were also noted commonly. The ATLL cells immunophenotype were typical, and the major subtype was CD4+ CD8- type. Confection of hepatitis B virus was detected in a high rate (54.5%). Ten patients received chemotherapy, and 2 cases in complete remission after chemotherapy received allogeneic hematopoietic stem cell transplantation. At the end of the follow-up, 7 cases died, 4 cases survived, 1 case was lost, and the median survival was 2.8 (0.9-10.8) months. We found a case had HTLV-1 provirus negative after transplantation. Conclusion: In the coastal area of Fujian Province, ATLL is not rare. Characteristics of those ATLL are typical. But prognosis is still unsatisfactory.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano , Leucemia-Linfoma de Células T do Adulto , Adulto , Idoso , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Imunofenotipagem , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Leucemia-Linfoma de Células T do Adulto/virologia , Linfoma , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Provírus
7.
Genet Mol Res ; 14(4): 12196-204, 2015 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-26505368

RESUMO

This study aims to explore the possible associations between a genetic variation in the miR-34b binding site in the 3'-untranslated region (UTR) of the methylenetetrahydrofolate reductase (MTHFR) gene (rs55763075) with male infertility in a Chinese population. Genotype distributions of the rs55763075 single nucleotide polymorphism were investigated by polymerase chain reaction and direct sequencing in a Chinese cohort that included 464 infertile men with idiopathic azoospermia or oligospermia and 458 controls with normal fertility. Overall, no significant differences in the distributions of the genotypes of the MTHFR rs55763075 polymorphism were detected between the infertility and control groups. A statistically significant increased risk of male infertility was found for carriers of the rs55763075 AA genotype when compared with homozygous carriers of the rs55763075 GG genotype in the azoospermia subgroup (OR = 1.721; 95% CI = 1.055-2.807; P = 0.031). Furthermore, we found that rs55763075 was associated with folate and homocysteine levels in patients with idiopathic azoospermia. Our results indicated that the MTHFR 3'-UTR rs55763075 polymorphism might modify the susceptibility to male infertility with idiopathic azoospermia.


Assuntos
Regiões 3' não Traduzidas/genética , Infertilidade Masculina/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Ácido Fólico/sangue , Genótipo , Homocisteína/sangue , Humanos , Infertilidade Masculina/fisiopatologia , Masculino , Pessoa de Meia-Idade
8.
Anaesthesia ; 67(11): 1232-6, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22827497

RESUMO

We prospectively evaluated the CEL-100 videolaryngoscope(TM) for insertion of double-lumen tracheal tubes in 48 consecutive patients who had been found to have an unanticipated Cormack and Lehane grade 3 (n=43) and grade 4 (n=5) laryngeal view and in whom two attempts at tracheal intubation using the Macintosh laryngoscope had failed. When the CEL-100 was subsequently employed, the glottic view improved in 45 (94%) patients. The view improved by one grade in 15 (31%) patients and by two grades in 30 (63%) patients, compared with the Macintosh blade (p<0.001). Double-lumen tracheal tube insertion was successful when using the CEL-100 in 43 out of 48 patients (90%; 95% CI 81-98%). This occurred on the first attempt in 27 (56%) patients, 14 (29%) on the second and two (4%) on the third. We conclude that the CEL-100 videolaryngoscope is an effective device in this context, and we therefore propose that this device can be used in circumstances when double-lumen tube insertion proves difficult.


Assuntos
Intubação Intratraqueal/métodos , Laringoscópios , Feminino , Humanos , Intubação Intratraqueal/instrumentação , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tamanho da Amostra , Procedimentos Cirúrgicos Torácicos , Falha de Tratamento
9.
Alcohol Clin Exp Res ; 19(3): 753-8, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7573804

RESUMO

Ethanol-induced fatty liver in rats was attenuated by repeated running exercise, and the protective effect of exercise was associated with the synergistic expression of heat shock proteins (HSP72). Rats were placed in four groups of six. The two ethanol-fed groups of rats received a liquid diet (Lieber-DeCarli formulation) in which 36% of the calories were derived from ethanol. One group remained sedentary (S/E), whereas the other was trained to run on a rodent treadmill at a speed of 27 m/min, 1 hr/day, 5 days/week, for 7 weeks (R/E). Two other groups--one exercised as previously mentioned (R/C) and one sedentary (S/C)--received control-liquid diets in which the ethanol was isocalorically substituted with a dextran/maltose mixture. The degree of fatty infiltration in liver sections stained with hematoxylin and eosin was graded on a 0-4 scale and the data analyzed by ANOVA on ranks. Ethanol significantly induced fatty infiltration in the S/E group, whereas fatty infiltration in the livers of the R/E group was not different from the S/C group. Electrophoresis and Western blotting of liver homogenates demonstrated that HSP72 was not expressed in either the S/C or S/E groups and was only slightly expressed in the R/C group. The combination of exercise and ethanol, however, resulted in an elevated expression of HSP72 in the R/E group. The content of HSP73 was unaffected by any treatment.


Assuntos
Fígado Gorduroso Alcoólico/prevenção & controle , Proteínas de Choque Térmico/metabolismo , Fígado/fisiopatologia , Esforço Físico/fisiologia , Animais , Etanol/toxicidade , Fígado Gorduroso Alcoólico/patologia , Fígado Gorduroso Alcoólico/fisiopatologia , Proteínas de Choque Térmico HSP72 , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Ratos , Ratos Sprague-Dawley
10.
Biochem Biophys Res Commun ; 205(1): 186-94, 1994 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-7999022

RESUMO

Alcohol dramatically reduced loss of heat shock proteins (HSP73) and prevented morphological damage in monolayers of hepatocytes prepared from alcohol-fed rats. The monolayers were treated with 0, 5, 25, or 100 mM alcohol and triplicate samples were assayed at 24, 48, 72, and 96 hr after exposure. The content of HSP73 was measured by PAGE electrophoresis and Western blotting with a mouse monoclonal anti-HSP70 IgG antibody. HSP72 is not expressed under these conditions. Damage to the hepatocytes, quantified by leakage of lactate dehydrogenase (LDH), was also decreased by 100 mM alcohol. Although the initial 100 mM alcohol concentration decreased logarithmically to 1.7 mM over the first 24 hr, the effect of alcohol on HSP73 loss, LDH leakage, and morphological damage was most pronounced at 96 hr.


Assuntos
Etanol/farmacologia , Proteínas de Choque Térmico/biossíntese , Fígado/efeitos dos fármacos , Animais , Células Cultivadas , Fígado/citologia , Fígado/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
11.
Mol Pharmacol ; 46(4): 639-43, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7526150

RESUMO

Previous studies have shown that exposure of phenobarbital-pretreated rats to halothane in 10% O2 causes centrilobular necrosis, induces expression of the 72-kDa heat shock protein (HSP72), and produces several trifluoroacetylated adducts. In the present study the time course of development of the centrilobular lesion, as measured by histochemistry, was compared with the time course of appearance of both trifluoroacetylated adducts and HSP72, as measured by Western blotting. One group of 20 rats was pretreated with phenobarbital for 5 days, whereas a second group of two rats was left as untreated controls. Ten phenobarbital-pretreated rats were exposed for 2 hr to 1% halothane in 10% O2 and 10 were exposed to 1% halothane in 20% O2. At either 2, 4, 6, or 24 hr after exposure, livers were excised and frozen without fixation. Thin sections stained with hematoxylin and eosin demonstrated that centrilobular lesions occurred at 6 hr and became extensive at 24 hr in rats pretreated with phenobarbital and exposed to 1% halothane in 10% O2. The time course of appearance of both trifluoroacetylated adducts and HSP72 was determined by Western blotting. Trifluoroacetylated adducts appeared in all rats exposed to halothane by 2 hr, lasted until 6 hr, and then diminished by 24 hr. In contrast, HSP72 was induced only in the rats pretreated with phenobarbital and exposed to 1% halothane in 10% O2. HSP72 appeared in both the nuclear and supernatant fractions at 6 hr after exposure and was intense 24 hr after exposure.


Assuntos
Halotano/farmacologia , Proteínas de Choque Térmico/biossíntese , Fígado/efeitos dos fármacos , Ácido Trifluoracético/metabolismo , Animais , Western Blotting , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Eletroforese em Gel de Poliacrilamida , Indicadores e Reagentes , Cinética , Fígado/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Corantes de Rosanilina , Coloração e Rotulagem
12.
Biochem Biophys Res Commun ; 199(2): 647-52, 1994 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-8135806

RESUMO

Immunocytochemical studies have revealed that one of the major heat shock proteins, HSP72, is induced in livers of rats that have been pretreated with phenobarbital and then administered halothane in a hypoxic gas mixture of 10% oxygen. To determine the sub-cellular localization of HSP72 in the livers of these rats 24 hr after halothane administration, cytoplasmic and nuclear fractions were prepared and separated by PAGE electrophoresis. Western blotting with a mouse monoclonal anti-HSP70 IgG antibody, which recognizes both the constitutive (HSP73) and inducible (HSP72) forms, revealed that HSP72 was induced and translocated into the nucleus in only those rats exposed to halothane under hypoxia following phenobarbital pretreatment. Nuclear translocation of HSP72 under the latter conditions was confirmed by immunocytochemical staining using gold-conjugated secondary antibodies followed by digital laser microscopy with Nomarski optics. Neither phenobarbital pretreatment alone nor phenobarbital plus hypoxia treatment induced HSP72. No alteration in amount of HSP73 was observed under any of these conditions.


Assuntos
Núcleo Celular/metabolismo , Halotano/farmacologia , Proteínas de Choque Térmico/metabolismo , Fígado/metabolismo , Animais , Anticorpos Monoclonais , Western Blotting , Nucléolo Celular/metabolismo , Núcleo Celular/efeitos dos fármacos , Proteínas de Choque Térmico/análise , Proteínas de Choque Térmico/biossíntese , Imuno-Histoquímica , Fígado/efeitos dos fármacos , Masculino , Fenobarbital/farmacologia , Ratos , Ratos Sprague-Dawley
13.
Yao Xue Xue Bao ; 29(5): 346-54, 1994.
Artigo em Chinês | MEDLINE | ID: mdl-7976352

RESUMO

This paper reports the synthesis of eleven N-(4-carbomethoxy-4-phthalimidobutanoyl)-N-substituted glycines (VII1-9), proline (VII10) and pyroglutamic acid (VII11) expected to have inhibitory activity on angiotensin converting enzyme. All of the compounds mentioned above and the corresponding t-butyl esters of VII1-9 were not reported in the literature previously. The structures were confirmed through their IR, 1HNMR, MS spectra and elemental analysis. In preliminary test in rats, compounds VII8, VII9 and VII10 showed marked hypotensive activity.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/síntese química , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
14.
J Toxicol Environ Health ; 39(2): 273-85, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8501770

RESUMO

Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been shown to decrease serum complement C3 levels in female B6C3F1 mice but failed to alter C3 production when added in vitro to either hepatoma cells (both human and mouse hepatoma cells) or mouse primary hepatocytes (Lin and White, 1993a). It has also been demonstrated that mouse liver intracellular C3 levels were not affected following TCDD exposure in vivo, while serum C3 levels were suppressed (Lin and White, 1993b). Therefore, further studies were undertaken to investigate the mechanism by which TCDD modulates newly synthesized serum C3 in vivo. Mouse serum C3 was depleted by an intravenous injection of 50 anti-complement units (ACU)/kg cobra venom factor (CVF). This dose of CVF depleted serum C3 levels to 9% of control at 24 h after treatment. Subsequently, serum C3 levels returned to 19% and 75% of the control level on d 3 and d 5. The recovery of serum C3 was then monitored following an acute oral exposure to 20 micrograms/kg TCDD. In mice exposed to both TCDD and CVF, serum C3 levels reached 15% and 69% of control on d 3 and d 5 after treatment; these results were not significantly different from those of mice treated with CVF alone. Furthermore, when the radiolabeled amino acid [3H]leucine was injected intravenously into either vehicle- or TCDD-treated mice, the incorporation of this labeled precursor into both C3 and other secreted plasma proteins was not inhibited by TCDD. These results demonstrated that TCDD did not decrease newly synthesized C3 in vivo. These studies provide additional support for the concept that TCDD does not act directly on hepatocytes to suppress C3 production. The lower serum C3 levels observed in vivo following TCDD exposure is not the result of a decrease in C3 production by hepatocytes.


Assuntos
Complemento C3/biossíntese , Fígado/efeitos dos fármacos , Dibenzodioxinas Policloradas/toxicidade , Administração Oral , Animais , Venenos Elapídicos , Feminino , Leucina , Fígado/imunologia , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Dibenzodioxinas Policloradas/administração & dosagem , Organismos Livres de Patógenos Específicos
15.
J Toxicol Environ Health ; 39(1): 107-19, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8492324

RESUMO

Earlier studies from this laboratory have shown that the complement system, especially the component C3, in female B6C3F1 mice is suppressed following TCDD exposure in vivo. However, the direct exposure of TCDD in vitro does not affect the C3-producing capacity of two types of hepatoma cells, as well as mouse primary hepatocytes. To investigate the effect of TCDD on C3 production by the liver following in vivo exposure, liver intracellular C3 levels and pro-C3, the precursor of the secreted C3, were examined in the present study. The results demonstrated that there was a dose-dependent increase of liver intracellular C3 levels (from 138% to 175% of control) immediately following TCDD (from 10 to 40 micrograms/kg) exposure. This increase was rapid (4 h after exposure), but transient (less than 2 h), and was not accompanied by an alteration of serum C3 levels. Studies using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed that the increase in liver intracellular C3 levels resulted from, at least partially, an increase in intracellular pro-C3. Serum C3 levels did not decrease until d 3 after exposure, when both liver intracellular C3 levels and pro-C3 in TCDD-treated mice were not different from those of the control mice. These results indicated that the modulation of liver intracellular C3 by TCDD did not correlate with the suppression of serum C3 levels following exposure.


Assuntos
Complemento C3/biossíntese , Fígado/efeitos dos fármacos , Dibenzodioxinas Policloradas/toxicidade , Administração Oral , Animais , Feminino , Fígado/metabolismo , Camundongos , Testes de Precipitina
16.
J Toxicol Environ Health ; 39(1): 27-41, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8492328

RESUMO

Previous studies from this laboratory have shown that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) decreased complement component C3 levels in female B6C3F1 mouse serum following in vivo acute or subchronic exposure (White et al., 1986). Since TCDD is a hepatotoxic compound and more than 90% of serum C3 is produced by the liver, studies were undertaken using mouse Hepa 1c1c7 (Hepa 1) hepatoma cell line to determine if TCDD acts directly on hepatocytes to inhibit C3 production. The C3-producing capacity of Hepa 1 cells was first examined. When confluent Hepa 1 cell monolayers were cultured in 24-well plates with serum-free medium, a detectable amount of C3 (14.1 +/- 0.8 ng/ml) was secreted as early as 1 h after culture and reached a plateau at 12 h (68.3 +/- 4.9 ng/ml). Furthermore, the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis demonstrated that the molecular weight of C3 in culture supernatant corresponded to that present in mouse serum. Human recombinant IL-1 beta (hrIL-1 beta), a known inducer of complement C3, at doses as low as 1 unit/ml increased the C3 production to 158% of control after 24 h of incubation. The effect of hrIL-1 beta was dose dependent, and the maximum tested dose of 10 units/ml increased C3 production to 256% of control. When cells were directly exposed to TCDD at concentrations from 10(-10) to 10(-6) M, there was no inhibitory effect on production of C3. TCDD also failed to block the stimulatory effect of 10 units/ml hrIL-1 beta added to the culture 1 h later. To verify that cultured Hepa 1 cells were able to respond to TCDD, 7-ethoxyresorufin O-deethylase (EROD) activity was measured under the same conditions. TCDD dose-dependently increased EROD activity of Hepa 1 cells at 24 h following exposure. The activity reached 56.7 +/- 3.0 pmol/min/mg protein with 10(-9) M TCDD, compared with 10.7 +/- 1.7 pmol/min/mg protein of vehicle-exposed cells. Our results indicate that the direct interaction of TCDD with Hepa 1 cells does not affect their C3-producing capacity, although EROD activity, a characteristic response mediated by the cellular TCDD/Ah receptor, was induced. The lack of effect of TCDD in vitro suggests that the decrease of serum C3 levels observed in vivo may result from an indirect effect of TCDD on hepatocytes.


Assuntos
Complemento C3/metabolismo , Neoplasias Hepáticas Experimentais/metabolismo , Dibenzodioxinas Policloradas/toxicidade , Animais , Citocromo P-450 CYP1A1 , Sistema Enzimático do Citocromo P-450/metabolismo , Feminino , Humanos , Neoplasias Hepáticas Experimentais/enzimologia , Camundongos , Oxirredutases/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos
17.
Fundam Appl Toxicol ; 19(4): 575-83, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1426716

RESUMO

The gut mucosal immune system may be a primary target for many ingested chemicals. Methods have been developed to examine the effects of chemicals on the systemic humoral immune response; however, studies to evaluate various methods of assessing the local gut mucosal immune response in a toxicology assay have been limited. The objectives of this study were to examine the effects of the known immunosuppressive compound, cyclosporine (CYS), on the generation of a cholera toxin (CT)-specific gut mucosal IgA response and evaluate the methods used to measure the gut IgA response. Groups of female B6C3F1 mice were left untreated or were treated daily, p.o., with corn oil (vehicle) or CYS at doses of 10 and 50 mg/kg for 20 days. On Days 3 and 13, mice were sensitized p.o. with CT. On Day 21, mice were terminated, gut washings were collected, and lamina propria lymphocytes were extracted from gut tissue with collagenase treatment. Cholera toxin-specific IgA in the gut washings was measured by an ELISA. The numbers of CT-specific IgA (CT-IgA) and total IgA antibody-forming cells (spot-forming cells, SFC) obtained from the lamina propria were determined by the ELISPOT method. A dose of 50 mg/kg CYS produced a significant decrease in the amount of CT-IgA in gut washings. This dose also decreased the number of cells recovered from the lamina propria by at least 50%. The amount of CT-specific SFC/million lamina propria cells decreased with a dose of 10 mg/kg CYS, whereas 50 mg/kg CYS did not alter the response.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Toxina da Cólera/imunologia , Ciclosporina/farmacologia , Imunoglobulina A Secretora/biossíntese , Mucosa Intestinal/imunologia , Administração Oral , Animais , Ciclosporina/administração & dosagem , Feminino , Mucosa Intestinal/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos
18.
Immunology ; 66(4): 539-45, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2469642

RESUMO

The B oligomer of pertussis toxin serves as a weak mitogen in the T lymphocyte, an effect which is associated with an early rise in cytosolic free calcium concentrations, as monitored by Fura-2 fluorescence. Upon co-administration of phorbol dibutyrate, a phorbol ester tumour promotor which activates protein kinase C, pertussis toxin-induced proliferation was synergistically enhanced, as measured by the increased uptake of [3H]thymidine, into cellular DNA. Although phorbol ester co-administration has often been associated with an inhibition of Ca2+-mobilizing pathways, phorbol dibutyrate pretreatment had no inhibitory effect on the pertussis toxin-induced calcium flux and may actually have enhanced this response slightly. Flow cytometric analysis of cell populations expanded by the combined regimen did not provide evidence for the preferential expansion of cells bearing either CD4 or CD8, the T-cell determinants representative of the helper-inducer and cytotoxic-suppressor subsets, respectively. Pertussis toxin and phorbol dibutyrate appear, therefore, to elicit polyclonal stimulation, rather than the selective activation of a given lymphocyte subset. Expression of the transferrin receptor, a marker for nutrient uptake, and CD25, the Tac component of the interleukin-2 (IL-2) receptor, was, however, synergistically enhanced in cells activated by the co-treatment procedure.


Assuntos
Antígenos de Diferenciação de Linfócitos T/análise , Ativação Linfocitária/efeitos dos fármacos , Toxina Pertussis , Dibutirato de 12,13-Forbol , Linfócitos T/efeitos dos fármacos , Fatores de Virulência de Bordetella/imunologia , Cálcio/metabolismo , Epitopos/análise , Humanos , Receptores de Interleucina-2/análise , Linfócitos T/imunologia , Linfócitos T/metabolismo
19.
Can J Vet Res ; 50(3): 380-3, 1986 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3017530

RESUMO

Vaccination of ducks with an apathogenic strain of duck enteritis virus resulted in protection against challenge with the virulent Lake Andes strain of duck enteritis virus by intramuscular inoculation or contact exposure. Antisera produced in the vaccinated ducks were able to transfer resistance against the challenge strain to recipient ducks. Antisera against duck enteritis virus were cytotoxic for duck enteritis virus-infected duck embryo fibroblasts in the presence of guinea pig complement. These in vivo and in vitro data suggest that the humoral immune mechanism plays a role in protecting ducks from duck enteritis virus infection.


Assuntos
Anticorpos Antivirais/imunologia , Patos/imunologia , Infecções por Herpesviridae/veterinária , Doenças das Aves Domésticas/imunologia , Vacinação/veterinária , Animais , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/prevenção & controle , Doenças das Aves Domésticas/prevenção & controle
20.
Avian Dis ; 28(4): 1026-36, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6098247

RESUMO

The prevalence of two infectious bursal disease (IBD) viruses--serotype 1, of chicken origin, and serotype 2, of turkey origin--was studied in California turkeys. Serum samples were collected from 15 turkey flocks representing nine counties. The virus-neutralization test was used. Overall, only 15% of 342 samples were positive for serotype 1, whereas 89% were positive for serotype 2. However, 12 out of 15 flocks had a least one sample positive for serotype 1, and 14 out of 15 flocks had at least one sample positive for serotype 2. Flocks with antibodies to serotype 1 had low geometric mean titers (GMTs) (1.5 to 8.8) and low-to-medium prevalence rates (5 to 53.3%). Flocks with antibodies to serotype 2 had high GMTs (36.8 to 2048) and high prevalence rates (60 to 100%). Results of this study lead us to question the efficacy of IBD vaccination in turkeys.


Assuntos
Vírus da Doença Infecciosa da Bursa/classificação , Doenças das Aves Domésticas/microbiologia , Infecções por Reoviridae/microbiologia , Reoviridae/classificação , Perus , Animais , Anticorpos Antivirais/análise , Especificidade de Anticorpos , California , Galinhas/microbiologia , Feminino , Masculino , Testes de Neutralização , Sorotipagem , Perus/microbiologia
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