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1.
Transplant Proc ; 51(3): 794-797, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30739717

RESUMO

INTRODUCTION: Frailty measures can predict perioperative surgical risk in liver transplant patients. The 5-meter walk test (5MWT) and hand grip strength (HGS) are easy and reproducible frailty measures. We hypothesized that they could capture frailty in liver transplant listed patients and would be associated with dropping out of the waiting list. METHODS: We conducted a retrospective analysis of patients undergoing outpatient liver transplant listing at the University of Pittsburgh Medical Center from 2013 to 2016. We compared demographics, baseline laboratory markers, 5MWT, and HGS between patients who were dropped from the waiting list for medical reasons and those who remained or were successfully transplanted. Bivariate statistical analysis was performed using Fisher exact or χ2 tests. RESULTS: We reviewed 197 patients listed for liver transplant. Average age was 57.1 years (range 20-74), and patients were predominantly white (90.4%). Patients' most common etiology of liver disease was hepatitis C (32.5%), 14 (7.1%) had a previous liver transplant, and average Model for End-Stage Liver Disease score upon listing was 16.0. Of the cohort, 38 (19.3%) were ultimately dropped from the waitlist due to non-hepatocellular carcinoma-related reasons. Patients dropped from the waiting list had weaker HGS (46.14 lb vs 59.6 lb; P < .005) and slower 5MWT speed (5MWT: 0.92 m/s vs 1.03 m/s; P < .005). CONCLUSION: The 5MWT and HGS can easily measure frailty in patients being evaluated for liver transplant. These tests are associated with waiting list dropout, indicating that they can be valuable tools in the evaluation of these patients.


Assuntos
Fragilidade/diagnóstico , Força da Mão , Transplante de Fígado , Listas de Espera , Velocidade de Caminhada , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Teste de Caminhada , Adulto Jovem
2.
J Clin Invest ; 59(4): 666-74, 1977 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-845255

RESUMO

Collagen synthesis was measured in liver slices obtained from mice with hepatosplenic schistosomiasis. Enlarged fibrotic livers from these mice contained 20 times more collagen than normal. This model of hepatic fibrosis results from an inflammatory granulomatous host response to Schistosoma mansoni ova in portal tracts, rather than from direct lover cell injury as with carbon tetrachloride-induced liver fibrosis. Collagen synthesis, as measured by the formation of labeled protein-bound hydroxyproline, occurred in granulomas isolated from fibrotic livers. Labeled collagen that cochromatographed with type I collagen was extracted with neutral salt solution from liver slices incubated with labeled proline. The free proline pool of the liver was doubled in infected mice; coordinately, liver slices from these animals showed maximal collagen production when the concentration of free proline in the medium was raised to 0.4 mM, the same level measured in the fibrotic livers. Under such conditions, collagen synthesis was at a rate equivalent to the formation of 5.4 nmol of protein-bound hydroxyproline per g liver in 6 h. In comparative incubations in medium containing 0.2 mM proline, fibrotic liver slices produced 16-fold more collagen than normal slices. The proline analogue, L-azetidine 2-carboxylic acid, effectively inhibited synthesis of labeled collagen by fibrotic liver slices. These studies show the synthesis of collagen in a reproducible animal model of the most prevalent form of human liver fibrosis. Difinitition of the controlling factors in this system is of interest for the general problem of fibrosis produced by immunological responses.


Assuntos
Colágeno/biossíntese , Fígado/metabolismo , Esquistossomose/metabolismo , Animais , Ácido Azetidinocarboxílico/metabolismo , Feminino , Granuloma/metabolismo , Hidroxiprolina/metabolismo , Hepatopatias Parasitárias/metabolismo , Camundongos , Tamanho do Órgão , Prolina/metabolismo , Schistosoma mansoni , Esquistossomose/patologia
3.
Poult Sci ; 86(6): 1196-205, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17495092

RESUMO

In this study, we produced a polyclonal antibody against unprocessed chicken myostatin and examined the effect of in ovo administration of the antibody on posthatch chicken growth and muscle mass. A PCR-amplified unprocessed chicken myostatin cDNA was cloned into an Escherichia coli expression vector, and myostatin proteins were expressed. Recombinant myostatin purified by electro-elution of the SDS-PAGE fractionated myostatin band was used as an immunogen to produce rabbit polyclonal antimyostatin antibody (pAb-AVM46). In Western blot analysis, the pAb-AVM46 showed high affinity to the myostatin propeptide, but little affinity to the mature myostatin. Two experiments examined the effect of in ovo administration of the pAb-AVM46 on posthatch chicken growth and skeletal muscle mass. In experiment 1, broilers from eggs injected once with 35 microg of the antibody into the yolk on d 3 of incubation had significantly lower combined thigh and leg weight at 4 wk posthatch than the controls that received no injection, or the broilers from eggs received the same dose of antibody into the albumen. In experiment 2, 2 different doses of the antibody (9 or 70 microg) were injected into the yolk, and the effects on body and muscle weight were examined at 5 wk posthatch. Birds from eggs injected with 70 microg of the antibody had significantly lighter (11.6%) combined thigh and leg weight than the control birds. The percentage of the combined thigh and leg weight to BW of the 70-microg group was also significantly lower than that of the control group (20.95 vs. 23.08%). The results of this study indicate that unprocessed full-length myostatin as an immunogen produced antibody populations having affinity mostly to the propeptide with little to the mature form. The decreased muscle weight observed in broilers injected with the antibody in the yolk indicates that myostatin activity was probably elevated by the binding of the antibody to the propeptide, and provides evidence that myostatin propeptide inhibits the biological activity of myostatin in broilers.


Assuntos
Anticorpos/administração & dosagem , Anticorpos/farmacologia , Galinhas/crescimento & desenvolvimento , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/crescimento & desenvolvimento , Fator de Crescimento Transformador beta/antagonistas & inibidores , Fator de Crescimento Transformador beta/imunologia , Animais , Especificidade de Anticorpos , Embrião de Galinha , Regulação da Expressão Gênica , Miostatina , Tamanho do Órgão/efeitos dos fármacos , Proteínas Recombinantes , Fator de Crescimento Transformador beta/metabolismo
4.
Biochim Biophys Acta ; 538(2): 328-33, 1978 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-202335

RESUMO

The activity of procollagen prolyl hydroxylase was measured in fibrotic liver obtained from mice with hepatosplenic schistosomiasis, an animal model of the most prevalent form of human liver fibrosis. Measurable activity of prolyl hydroxylase in fibrotic liver supernatants was 47-fold higher than that of normal liver. The effect of prolyl hydroxylase inhibition on collagen synthesis in fibrotic liver slices was studied, using 8,9-dihydroxy-7-methyl benzo[b]quinolizinium bromide (GPA 1734). This compound was shown in other systems to inhibit prolyl and lysyl hydroxylations by iron chelation at concentrations which did not affect total protein synthesis. The formation of nondialyzable labelled hydroxyproline was inhibited by GPA 1734, 40, 70 and 95% at 30, 50 and 100 micrometer, respectively. Incorporation of proline into total liver protein was unaffected at 30 and 50 micrometer, but was inhibited 20% at 100 micrometer GPA 1734. Underhydroxylated collagen synthesized by liver slices with GPA 1734 was extracted with neutral salt solution and was subsequently hydroxylated with partially-purified prolyl hydroxylase to the same extent as control material synthesized in the absence of GPA 1734.


Assuntos
Cirrose Hepática/enzimologia , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Esquistossomose/enzimologia , 2-etil-1,3,4,6,7,11b-hexaidro-3-isobutil-9,10-dimetoxi-2H-benzo(a)quinolizin-2-ol/análogos & derivados , 2-etil-1,3,4,6,7,11b-hexaidro-3-isobutil-9,10-dimetoxi-2H-benzo(a)quinolizin-2-ol/farmacologia , Animais , Quelantes de Ferro/farmacologia , Camundongos , Pró-Colágeno/metabolismo , Pró-Colágeno-Prolina Dioxigenase/antagonistas & inibidores , Schistosoma mansoni
5.
Clin Oncol (R Coll Radiol) ; 27(9): 514-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26150375

RESUMO

AIMS: Modern radiotherapy uses techniques to reliably identify tumour and reduce target volume margins. However, this can potentially lead to an increased risk of geographic miss. One source of error is the accuracy of target volume delineation (TVD). Colleague peer review (CPR) of all curative-intent lung cancer plans has been mandatory in our institution since May 2013. At least two clinical oncologists review plans, checking treatment paradigm, TVD, prescription dose tumour and critical organ tolerances. We report the impact of CPR in our institution. MATERIALS AND METHODS: Radiotherapy treatment plans of all patients receiving radical radiotherapy were presented at weekly CPR meetings after their target volumes were reviewed and signed off by the treating consultant. All cases and any resultant change to TVD (including organs at risk) or treatment intent were recorded in our prospective CPR database. The impact of CPR over a 13 month period from May 2013 to June 2014 is reported. RESULTS: One hundred and twenty-two patients (63% non-small cell lung carcinoma, 17% small cell lung carcinoma and 20% 'clinical diagnosis') were analysed. On average, 3.2 cases were discussed per meeting (range 1-8). CPR resulted in a change in treatment paradigm in 3% (one patient proceeded to induction chemotherapy, two patients had high-dose palliative radiotherapy). Twenty-one (17%) had a change in TVD and one (1%) patient had a change in dose prescription. In total, 6% of patients had plan adjustment after review of dose volume histogram. CONCLUSION: The introduction of CPR in our centre has resulted in a change in a component of the treatment plan for 27% of patients receiving curative-intent lung radiotherapy. We recommend CPR as a mandatory quality assurance step in the planning process of all radical lung plans.


Assuntos
Neoplasias Pulmonares/radioterapia , Planejamento de Assistência ao Paciente , Revisão dos Cuidados de Saúde por Pares , Radioterapia/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente/normas , Garantia da Qualidade dos Cuidados de Saúde
6.
Am J Trop Med Hyg ; 34(4): 750-3, 1985 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-4025688

RESUMO

UNLABELLED: Coupled adult pairs of Schistosoma mansoni were incubated in medium containing either peripheral or portal serum from rat, rabbit, hamster or humans. Daily egg production was measured. In all cases egg production was significantly increased for pairs in the presence of portal sera compared with that in the presence of peripheral sera. Fractionation of rabbit portal serum according to molecular weight demonstrated that the most active component(s) were in the range of 2,000 to 50,000. These fractions were as effective in stimulating oviposition as whole portal serum. CONCLUSIONS: 1) portal serum factor(s) that stimulate S. mansoni oviposition are present in susceptible and non-susceptible hosts; 2) the molecular weight range for the active components is larger than would be expected for simple carbohydrates, amino acids or free fatty acids absorbed from the gastrointestinal tract.


Assuntos
Fenômenos Fisiológicos Sanguíneos , Sistema Porta/fisiologia , Schistosoma mansoni/fisiologia , Adulto , Animais , Fracionamento Químico , Cricetinae , Feminino , Humanos , Masculino , Mesocricetus , Peso Molecular , Coelhos , Ratos , Ratos Endogâmicos , Reprodução , Schistosoma mansoni/efeitos dos fármacos
7.
Am J Trop Med Hyg ; 35(6): 1185-91, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3098125

RESUMO

Liver fibrosis in schistosomiasis is associated with prominent accumulations of fibroblasts. Primary cell cultures were prepared from the fibrotic livers of Schistosoma mansoni-infected mice, and cells with the appearance of fibroblasts by light microscopy were isolated from these cultures. Proliferation of these cells was examined in coculture experiments with syngeneic inflammatory cells. T cell-enriched mononuclear cells from spleens of S. mansoni-infected or normal mice, and Kupffer cell/macrophages from fibrotic liver all stimulated the proliferation of liver fibroblasts, as measured by 3H-thymidine uptake. Primary cultures of mouse skin fibroblasts showed similar responses to coculture, but an established fibroblast line, 3T3, was unresponsive. Cell-free supernatant medium from coculture experiments did not affect fibroblast proliferation, perhaps because of the requirement for serum in the culture medium. Liver fibroblasts derived from this disease model may be especially suitable for study of the interaction between tissue inflammation and fibrosis.


Assuntos
Fígado/parasitologia , Esquistossomose mansoni/patologia , Animais , Divisão Celular , Células Cultivadas , Feminino , Fibroblastos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C
8.
Am J Trop Med Hyg ; 38(1): 111-7, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3124644

RESUMO

Primary cell cultures from the livers of mice infected with Schistosoma mansoni were prepared and cells with the appearance of fibroblasts by light microscopy were isolated. Collagen synthesis was estimated by measuring incorporation of 14C-proline into collagenase-sensitive proteins for both culture media and cell layers. Coculture of splenic T cells from infected mice with these hepatic fibroblasts caused greater selective and specific reduction in collagen production than did coculture using spleen cells from normal mice. There was a parallel inhibition in collagen within the cell layer which indicates that the marked decrease in collagen production was due to inhibition of synthesis and not related to changes in solubility or secretion. Primary culture of mouse skin fibroblasts showed similar responses to coculture but an established fibroblast line, 3T3, was unresponsive. Inflammatory cells appear to influence hepatic fibroblasts isolated under our experimental condition in several ways, such as opposite effects on collagen synthesis and cell proliferation.


Assuntos
Colágeno/biossíntese , Leucócitos Mononucleares/fisiologia , Esquistossomose mansoni/metabolismo , Linfócitos T/fisiologia , Animais , Linhagem Celular , Feminino , Fibroblastos/metabolismo , Cinética , Células de Kupffer/fisiologia , Fígado/imunologia , Fígado/metabolismo , Fígado/patologia , Camundongos , Camundongos Endogâmicos BALB C , Biossíntese de Proteínas
9.
Am J Trop Med Hyg ; 41(4): 454-9, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2508503

RESUMO

We have previously shown that co-culture of T cell enriched spleen lymphocytes can reduce collagen synthesis and stimulate proliferative activity by liver fibroblasts from S. mansoni infected mice. The present study examines which subset of T cells is responsible for this modulation. Co-culture of fibroblasts with the total T cell population lead to significant stimulation in fibroblast proliferative activity and a significant decrease in the incorporation of 14C-proline into collagenase-sensitive protein. There was virtually no effect on total incorporation of 14C-proline in non-collagen proteins. An additional significant increase in fibroblast proliferative activity and another significant decrease in collagen synthesis accompanied by a 2-fold increase in non-collagen protein production was noted when fibroblasts were co-cultured with Lyt-1+ cells. Co-culture of fibroblasts with Lyt-2+ cells did not differ significantly from co-culture with total T cells. Mitomycin treatment of the lymphocytes blunted their specific effects, suggesting that proliferation of T cells is required for maximal exertion of their regulatory activity. These results suggest that the T cells which mediate these effects belong to the Lyt-1+ helper class and are distinct from the Lyt-2+ suppressor cells.


Assuntos
Fibroblastos/metabolismo , Fígado/metabolismo , Esquistossomose/metabolismo , Linfócitos T/metabolismo , Animais , Comunicação Celular , Células Cultivadas , Colágeno/biossíntese , Feminino , Fígado/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Mitomicina , Mitomicinas/farmacologia , Baço/efeitos dos fármacos , Baço/metabolismo , Linfócitos T/efeitos dos fármacos , Timidina/metabolismo
10.
Am J Trop Med Hyg ; 32(6): 1364-9, 1983 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6650737

RESUMO

The collagen content of the liver, measured as hepatic hydroxyproline, was examined for a period of up to 52 weeks following Schistosoma mansoni infection. Hepatic fibrosis was much more marked in S. mansoni-infected mice of an outbred ICR strain than in C57BL/6J mice, while C3H/HeN mice occupied an intermediate position. The marked difference in hepatic fibrosis in ICR and C57BL/6J mice correlated with more rapid in vitro synthesis of collagen by the livers of infected ICR mice. Strains of mice exhibiting high and low levels of fibrosis provide an excellent tool for examining mechanisms of murine schistosomal hepatic fibrosis and its genetic regulation.


Assuntos
Fígado/patologia , Esquistossomose/patologia , Animais , Colágeno/biossíntese , Feminino , Granuloma/patologia , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Schistosoma mansoni , Esquistossomose/genética , Esquistossomose/metabolismo
11.
Am J Trop Med Hyg ; 50(4): 499-505, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8166357

RESUMO

Advanced liver fibrosis is generally considered to be irreversible. We studied the reversibility of marked liver fibrosis in rabbits infected with Schistosoma japonicum. We determined liver collagen content, collagen biosynthesis, and collagenase activity using serial biopsy specimens obtained 20, 40, and 60 weeks after infection. Reversibility of this process was investigated in rabbits cured of infection at 21 weeks; control rabbits not cured of infection were also studied. At 20 weeks, liver collagen content was 16-fold greater than normal, with accumulation of collagen types I, III, and V. Synthesis of collagen within fibrotic liver slices was 10-fold greater than normal. Liver collagenolytic activity for a type I substrate was 19-fold greater than normal. After parasitologic cure, a striking morphologic reversal of fibrosis occurred during the subsequent 40 weeks, with the return of liver collagen content to three-fold greater than normal and a 75% decrease in synthetic rates compared with those at 20 weeks (P < 0.01). Collagenolytic activity remained elevated to the same degree noted at 20 weeks. A similar but lesser resolution of fibrosis also occurred in untreated control rabbits, coincident with a spontaneous decrease in new egg deposition known to occur in this model system. We conclude that advanced liver fibrosis in S. japonicum-infected rabbits is slowly reversible after cure or senescence of the infection. A possible mechanism for this reversal is persistently increased collagenolysis as collagen synthesis diminishes.


Assuntos
Cirrose Hepática/etiologia , Fígado/patologia , Esquistossomose Japônica/complicações , Animais , Colágeno/análise , Colágeno/biossíntese , Colágeno/metabolismo , Colagenases/metabolismo , Difenilamina/análogos & derivados , Difenilamina/uso terapêutico , Isotiocianatos/uso terapêutico , Fígado/química , Fígado/parasitologia , Cirrose Hepática/patologia , Masculino , Contagem de Ovos de Parasitas , Coelhos , Schistosoma japonicum/crescimento & desenvolvimento , Esquistossomose Japônica/tratamento farmacológico , Esquistossomose Japônica/patologia , Esquistossomicidas/uso terapêutico
12.
Am J Trop Med Hyg ; 35(5): 1035-9, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3094391

RESUMO

Three hundred twenty-four individuals in a farming village located in the Nile Delta of Egypt were serially tested for hepatitis markers and Schistosoma mansoni to determine whether there is an increased risk of hepatitis B in persons infected with schistosomiasis. One-half of the subjects had stools positive for S. mansoni. Thirty-seven percent of the individuals had been infected with hepatitis B, and 3% were chronic HBsAg carriers. No statistical association was found between S. mansoni infection and hepatitis B infection, including chronic hepatitis B. Although there was no evidence of an association between these 2 pathogens, larger nonhospital based studies are needed to resolve this question.


Assuntos
Hepatite B/etiologia , Esquistossomose mansoni/complicações , Adolescente , Adulto , Idoso , Portador Sadio , Criança , Pré-Escolar , Egito , Feminino , Anticorpos Anti-Hepatite B/análise , Antígenos de Superfície da Hepatite B/análise , Humanos , Masculino , Pessoa de Meia-Idade , Risco
13.
Am J Trop Med Hyg ; 36(3): 549-53, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-2953263

RESUMO

Because dual infection with Schistosoma mansoni and hepatitis B may lead to severe liver disease, populations living in schistosomiasis-endemic areas might benefit if effectively immunized against hepatitis B. To determine whether a plasma-derived hepatitis B vaccine is immunogenic in patients with schistosomiasis, 32 individuals infected with S. mansoni were given three 20-micrograms doses of Heptavax-B vaccine and treated with praziquantel. Antibody to hepatitis B surface antigen developed in 90.6% of the study subjects after three doses of vaccine. Five patients (15.6%) had a weak response to the vaccine, and three patients (9.4%) failed to develop antibody. A weak or failed response to the vaccine was significantly associated with the presence of hepatosplenomegaly. A plasma-derived vaccine is immunogenic for persons infected with S. mansoni; however, vaccine response is diminished in hepatosplenic schistosomiasis.


Assuntos
Anticorpos Anti-Hepatite B/biossíntese , Antígenos de Superfície da Hepatite B/imunologia , Esquistossomose mansoni/imunologia , Vacinas contra Hepatite Viral/imunologia , Adolescente , Adulto , Criança , Vacinas contra Hepatite B , Hepatomegalia , Humanos , Imunização Secundária , Masculino , Esquistossomose mansoni/patologia , Esplenomegalia , Vacinação
14.
Am J Trop Med Hyg ; 32(2): 316-25, 1983 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6340541

RESUMO

Liver biopsies of four patients with hepatosplenic schistosomiasis, two patients with schistosomiasis and chronic active hepatitis, two patients with chronic active hepatitis and four control patients with no clinical evidence of either disease, were examined by standard light microscopic techniques, electron microscopy and immunocytochemical staining for collagen type I, III and B. Pure schistosomiasis showed the classical "clay-pipe stem fibrosis" and granulomata composed of eosinophils, macrophages and lymphocytes. In that group, the hepatocellular damage was less conspicuous than in the groups with chronic hepatitis and was usually confined to the granulomatous or fibrotic areas. Destruction of the normal architecture and infiltration by macrophages and lymphocytes with severe damage of hepatocytes was found only in the cases of chronic active hepatitis, with or without associated schistosomiasis. Increased collagen deposits were demonstrated in all three groups. Types I, III and B were found in the enlarged portal triads and fibrotic septa. The intranodular or intralobular collagen stained negatively for type I and strongly positive for types III and B.


Assuntos
Colágeno/metabolismo , Fígado/patologia , Esquistossomose/patologia , Colágeno/imunologia , Imunofluorescência , Histocitoquímica , Humanos , Fígado/ultraestrutura , Microscopia Eletrônica , Schistosoma mansoni
15.
Am J Trop Med Hyg ; 34(2): 314-21, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3985273

RESUMO

We examined the effect of parasitologic cure of S. mansoni infection on liver fibrosis in mice. Praziquantel, 250 mg/kg body weight, was administered orally to mice 8 weeks after infection with 50 S. mansoni cercariae. We assessed liver fibrosis by chemical measurement of collagen content as measured by the estimation of hydroxyproline and by histologic examination at the time of treatment, and at 10 and 20 weeks post-treatment, in comparison with the same measurements in untreated S. mansoni-infected mice and age-matched normal control mice. The extent of infection was monitored by liver egg counts. Compared to normal uninfected mice, mice with untreated S. mansoni infection showed steady accumulation of liver collagen at the 3 measurement periods, reaching an average level of 15-fold greater than that found in normal mice at 28 weeks after infection. Mice treated with praziquantel showed a prompt decrease in S. mansoni liver egg load with no viable eggs 10 weeks after treatment. Liver fibrosis was modestly diminished in treated mice compared to untreated controls 10 weeks after treatment; fibrosis was arrested and liver collagen content had diminished to normal levels by 20 weeks after treatment. No praziquantel toxicity was noted. The survival of treated mice was markedly greater than that of untreated infected animals. We conclude that parasitologic cure of murine S. mansoni infection is followed by arrest and eventual partial reversal of liver fibrosis under the conditions employed.


Assuntos
Isoquinolinas/uso terapêutico , Fígado/patologia , Praziquantel/uso terapêutico , Esquistossomose/tratamento farmacológico , Animais , Colágeno/análise , Granuloma/patologia , Hidroxiprolina/análise , Fígado/análise , Fígado/parasitologia , Hepatopatias/patologia , Masculino , Camundongos , Tamanho do Órgão , Contagem de Ovos de Parasitas , Schistosoma mansoni , Esquistossomose/parasitologia , Esquistossomose/patologia
16.
Arch Dermatol ; 127(8): 1207-13, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1863081

RESUMO

First used in World War I, chemical blistering agents present a serious medical threat that has stimulated renewed interest in the light of extensive use in recent conflicts. Current medical management cannot yet prevent or minimize injury from the principal agent of concern--sulfur mustard. Research directed at this goal depends on defining effective intervention in the metabolic alterations induced by exposure to sulfur mustard.


Assuntos
Arsenicais , Guerra Química , Descontaminação/métodos , Oftalmopatias/induzido quimicamente , Gás de Mostarda/toxicidade , Doenças Respiratórias/induzido quimicamente , Dermatopatias/induzido quimicamente , Intoxicação por Arsênico , Humanos , Dermatopatias/prevenção & controle , Dermatopatias/terapia
17.
Clin Chim Acta ; 177(1): 11-20, 1988 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-3141089

RESUMO

Colchicine, an antimicrotubular agent, was shown to block the transcellular movement of certain structural macromolecules such as collagen. In the present study, the effect of colchicine on collagen synthesis and secretion by monolayer cultures of fibroblasts from livers of mice infected with Schistosoma mansoni was investigated. The effect of colchicine on proliferation of these fibroblasts was studied as well. Collagen and non-collagen protein synthesis was measured by incubating cultures with [14C]proline and measuring the incorporation of radioactivity into these protein fractions in both culture media and cell layers. Proliferation was measured by [3H]thymidine uptake. The isolated fibroblasts actively formed collagen and secreted most of it into the culture medium; 10-20% of the collagenase-sensitive radioactive protein remained in the cell layer. The addition of colchicine to culture medium led to selective inhibition of collagen formation with negligible effects on non-collagen protein synthesis. Fibroblast proliferation was also reduced by colchicine treatment. Both inhibition of collagen synthesis and inhibition of fibroblast proliferation were dose-dependent. Comparison of medium and cell layer collagen radioactivity confirmed inhibition of synthesis rather than only inhibition of secretion. These data suggest that colchicine has a specific effect on synthesis of collagen and proliferative activity by fibroblasts from S. mansoni-infected liver and may, therefore, be useful in modulating schistosomal hepatic fibrosis.


Assuntos
Colchicina/farmacologia , Colágeno/biossíntese , Fígado/metabolismo , Esquistossomose mansoni/metabolismo , Animais , Células Cultivadas , Colchicina/administração & dosagem , Meios de Cultura , Relação Dose-Resposta a Droga , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos , Camundongos Endogâmicos BALB C , Biossíntese de Proteínas
18.
Toxicology ; 142(2): 97-109, 2000 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-10685509

RESUMO

Aluminum toxicity is well documented but the mechanism of action is poorly understood. In renal failure patients with aluminum overload, disturbances in iron metabolism leading to anemia are apparent. Few animal models, however, have been used to study the effects of dietary aluminum on iron metabolism. The purpose of this study was to determine if dietary aluminum exposure alters tissue iron and ferritin concentrations in the chick, as has been found in cultured human cells exposed to aluminum. Groups of day-old chicks were fed purified diets containing one of two levels of iron (control or high iron), and one of three levels of aluminum chloride in a 2 x 3 factorial design. Diets were consumed ad libitum for 1 week, then pair-feeding was initiated for 2 more weeks. A seventh group consumed a low iron diet ad libitum for comparative purposes. After the 3-week feeding period, samples of kidney, liver, and intestinal mucosa were analyzed for nonheme iron and ferritin concentrations by a colorimetric assay and SDS-PAGE, respectively. Results showed that dietary aluminum intake reduced iron stores in liver and intestine, but had no effect on nonheme iron levels in the kidney. Ferritin levels were reduced by aluminum intake in all tissues studied. The decreases in tissue ferritin levels were proportionately more than the decreases in tissue nonheme iron levels. This resulted in increased nonheme iron to ferritin ratios that amounted to as much as 140 and 525% in kidney and intestine, respectively. These findings are consistent with the interpretation that, in the growing chick, dietary aluminum can inhibit iron absorption, disrupt the regulation of tissue ferritin levels by iron, and potentially alter the compartmentalization and protective sequestration of iron within cells.


Assuntos
Alumínio/toxicidade , Ferritinas/análise , Ferro/análise , Animais , Galinhas , Eletroforese em Gel de Poliacrilamida , Mucosa Intestinal/química , Mucosa Intestinal/efeitos dos fármacos , Proteínas Reguladoras de Ferro , Proteínas Ferro-Enxofre/metabolismo , Rim/química , Rim/efeitos dos fármacos , Fígado/química , Fígado/efeitos dos fármacos , Proteínas de Ligação a RNA/metabolismo , Aumento de Peso/efeitos dos fármacos
19.
Brain Lang ; 51(3): 383-405, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8719073

RESUMO

The present study examined the extent to which verbal auditory agnosia (VAA) is primarily a phonemic decoding disorder, as contrasted to a more global defect in acoustic processing. Subjects were six young adults who presented with VAA in childhood and who, at the time of testing, showed varying degrees of residual auditory discrimination impairment. They were compared to a group of young adults with normal language development matched for age and gender. Cortical event-related potentials (ERPs) were recorded to tones and to consonant-vowel stimuli presented in an "oddball" discrimination paradigm. In addition to cortical ERPs, auditory brainstem responses (ABRs) and middle latency responses (MLRs) were recorded. Cognitive and language assessments were obtained for the VAA subjects. ABRs and MLRs were normal. In comparison with the control group, the cortical ERPs of the VAA subjects showed a delay in the N1 component recorded over lateral temporal cortex both to tones and to speech sounds, despite an N1 of normal latency overlying the frontocentral region of the scalp. These electrophysiologic findings indicate a slowing of processing of both speech and nonspeech auditory stimuli and suggest that the locus of this abnormality is within the secondary auditory cortex in the lateral surface of the temporal lobes.


Assuntos
Agnosia/diagnóstico , Agnosia/fisiopatologia , Percepção da Fala , Lobo Temporal/fisiopatologia , Adolescente , Adulto , Agnosia/complicações , Potenciais Evocados Auditivos , Potenciais Evocados Auditivos do Tronco Encefálico , Feminino , Humanos , Transtornos da Linguagem/complicações , Tempo de Reação , Testes de Discriminação da Fala
20.
Poult Sci ; 71(7): 1188-95, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1641382

RESUMO

Effects of dietary aluminum chloride and niacin on bone mineral content and bone structural measurements were studied using young male Leghorn chicks. Standard chick rations containing .8% Ca and .4 or .5% available P were fed as control diets in three experiments. Experimental diets contained .05, .1, or .3% Al, or 1.0 or 1.5% niacin, or both and were fed for 2 wk. Tibia weights were decreased by 1.5% niacin, .3% Al, and by .1% Al plus 1.5% niacin (P less than .05). Breaking strength of tibiae was decreased (P less than .05) by 1.5% niacin, .1% Al, and .1% Al plus 1.5% niacin. Ultimate stress, which is force per unit area, was decreased by .3% Al and .05% Al plus 1.5% niacin (P less than .05). Niacin had no significant effect on bone mineral content. In Experiment 3, .3% Al decreased P, Ca, Mg, and Zn content of the tibiae (P less than .05). These findings indicate that feeding high levels of supplemental niacin results in decreased bone strength in chicks with no change in mineral content of the tibiae. Aluminum fed at levels of .3% of the diet causes a decrease in bone strength with concomitant changes in bone mineral content.


Assuntos
Compostos de Alumínio , Alumínio/farmacologia , Densidade Óssea/efeitos dos fármacos , Galinhas/anatomia & histologia , Cloretos/farmacologia , Niacina/farmacologia , Tíbia/efeitos dos fármacos , Alumínio/administração & dosagem , Cloreto de Alumínio , Análise de Variância , Animais , Cloretos/administração & dosagem , Ingestão de Alimentos/efeitos dos fármacos , Masculino , Niacina/administração & dosagem , Tíbia/fisiologia , Aumento de Peso/efeitos dos fármacos
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