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1.
HIV Med ; 20(5): 330-336, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30924576

RESUMO

OBJECTIVES: Vertical transmission of HIV can be effectively controlled through antenatal screening, antiretroviral treatment and the services provided during and after childbirth for mother and newborn. In Italy, the National Health Service guarantees universal access to prenatal care for all women, including women with HIV infection. Despite this, children are diagnosed with HIV infection every year. The aim of the study was to identify missed opportunities for prevention of mother-to-child transmission of HIV. METHODS: The Italian Register for HIV Infection in Children, which was started in 1985 and involves 106 hospitals throughout the country, collects data on all new cases of HIV infection in children. For this analysis, we reviewed the database for the period 2005 to 2015. RESULTS: We found 79 HIV-1-infected children newly diagnosed after birth in Italy. Thirty-two of the mothers were Italian. During the pregnancy, only 15 of 19 women with a known HIV diagnosis were treated with antiretroviral treatment, while, of 34 women who had received an HIV diagnosis before labour began, only 23 delivered by caesarean section and 17 received intrapartum prophylaxis. In 25 mothers, HIV infection was diagnosed during pregnancy or in the peripartum period. Thirty-one newborns received antiretroviral prophylaxis and 39 received infant formula. CONCLUSIONS: We found an unacceptable number of missed opportunities to prevent mother-to-child transmission (MCTC). Eliminating HIV MTCT is a universal World Health Organization goal. Elucidating organization failures in Italy over the past decade should help to improve early diagnosis and to reach the zero transmission target in newborns.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/epidemiologia , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Complicações Infecciosas na Gravidez/epidemiologia , Cesárea/estatística & dados numéricos , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , Acessibilidade aos Serviços de Saúde , Humanos , Lactente , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Itália/epidemiologia , Masculino , Gravidez , Sistema de Registros , Medição de Risco
2.
Aliment Pharmacol Ther ; 44(6): 568-75, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27464469

RESUMO

BACKGROUND: Nosocomial infections are a major public health issue and preventative strategies using probiotics and micronutrients are being evaluated. AIM: To investigate the efficacy of a mixture of Lactobacillus GG and micronutrients in preventing nosocomial infections in children. METHODS: A randomised, double-blind, placebo-controlled trial was conducted in hospitalised children. Children (6 months to 5 years of age) received Lactobacillus GG (6 × 10(9) CFU/day) together with vitamins B and C and zinc or placebo, for 15 days, starting on the first day of hospitalisation. The incidence of gastrointestinal and respiratory nosocomial infections after discharge was determined by follow-up telephone call at 7 days. After 3 months, another telephone call estimated the incidence of further infections during follow-up. RESULTS: Ninety children completed the follow-up. Of 19/90 children with a nosocomial infection (20%), 4/45 children (9%) were in the treatment group and 15/45 (33%) in the placebo group (P = 0.016). Specifically, 2/45 (4%) children in the treatment group vs. 11/45 (24%) children in the placebo group (P = 0.007) presented with diarrhoea. The duration of hospitalisation was significantly shorter in the treatment group (3.9 days ± 1.7 vs. 4.9 ± 1.2; P = 0.003). At the follow-up, a total of 11/45 (24.4%) children in the treatment group had at least one episode of infection compared to 22/45 (48.9%) in the placebo group (P = 0.016). CONCLUSION: A mixture containing Lactobacillus GG and micronutrients may reduce the incidence of nosocomial infections, supporting the hypothesis that this may represent a valid strategy to prevent nosocomial infections.


Assuntos
Infecção Hospitalar/prevenção & controle , Lacticaseibacillus rhamnosus/fisiologia , Micronutrientes/uso terapêutico , Probióticos/uso terapêutico , Criança , Pré-Escolar , Diarreia/dietoterapia , Diarreia/microbiologia , Método Duplo-Cego , Feminino , Hospitalização , Humanos , Incidência , Lactente , Masculino , Placebos , Zinco/uso terapêutico
5.
Clin Nutr ; 28(3): 256-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19269721

RESUMO

BACKGROUND & AIMS: Iodine supplementation of parenterally fed infants recommended by ESPGHAN is 1 microg/kg/day. To assess nutritional and thyroid status of children on parenteral nutrition (PN) through urinary iodine concentration (UIC). PATIENTS AND METHODS: Children (1-17 yrs), undergoing PN and receiving an iodine supply of 1 microg/kg/day, were enrolled from 2000 to 2007. RESULTS: We observed 15 children (10 males, mean age 76.53+/-60.4 months) on PN from 14 to 84 weeks (mean 38.5+/-21.4). Ten were on TPN and five on PPN; nine had short bowel syndrome (SBS) and six had other intestinal diseases requiring PN. Iodine supply in TPN ranged between 1 and 1.6 microg/kg/day (mean 1.1+/-0.3 microg/kg/day), while in PPN it ranged from 2.3 to 2.8 microg/kg/day (mean 2.6+/-0.7 microg/kg/day). We found an inverse correlation between duration of PN in months and UIC (P=0.05). Four weeks after PN onset, UIC<100 microg/L was found in all SBS patients and 3/6 non-SBS patients (P<0.05). After 12 weeks, 8/15 (53%) patients had UIC<50 microg/L, but thyroxine, TSH and thyroid volume remained unchanged. CONCLUSIONS: A PN iodine supply of 1 microg/kg/day may be suboptimal. Higher supplies should be evaluated in controlled trials.


Assuntos
Fenômenos Fisiológicos da Nutrição Infantil , Iodo/administração & dosagem , Iodo/urina , Necessidades Nutricionais , Nutrição Parenteral , Adolescente , Criança , Pré-Escolar , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Feminino , Humanos , Lactente , Enteropatias/fisiopatologia , Enteropatias/terapia , Iodo/deficiência , Masculino , Estado Nutricional , Nutrição Parenteral/efeitos adversos , Nutrição Parenteral Total/efeitos adversos , Estudos Prospectivos , Síndrome do Intestino Curto/fisiopatologia , Síndrome do Intestino Curto/terapia , Glândula Tireoide/anatomia & histologia , Glândula Tireoide/fisiologia
6.
J Endocrinol Invest ; 31(7): 592-6, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18787374

RESUMO

OBJECTIVES: To assess the features of fat redistribution, detected by clinical and ultrasound (US) methods, and the presence of metabolic disorders in HIV-infected children undergoing antiretroviral therapy. To evaluate if serum levels of resistin, a hormone produced only by visceral adipose tissue, are a marker of fat redistribution in these patients. DESIGN AND METHODS: Forty-five consecutive symptomatic HIV-infected children were considered for inclusion in the study. Patients were enrolled if treated for at least 6 months with antiretroviral therapy with or without protease inhibitor (PI) and if compliant to the study protocol. Patients were evaluated for: anthropometric measures, fat redistribution by clinical and US methods, serum lipids, parameters of insulin resistance by homeostasis model assessment for insulin resistance, serum resistin levels by an enzyme-linked immunosorbent assay. RESULTS: Eighteen children fulfilled the inclusion criteria and were enrolled in the study. Twelve (66%) children had clinical and/or US evidence of fat redistribution; 9 (75%) of them were on PI therapy; only 3 of 6 children without fat redistribution were on PI therapy (p<0.05). Serum lipids and insulin resistance parameters did not differ between children with or without fat redistribution. There was a highly significant linear correlation between visceral fat detected by US and circulating resistin levels (r=0.87; p<0.0001). CONCLUSIONS: Fat redistribution occurred in most HIV-infected children undergoing PI therapy. Because serum resistin levels reflect the amount of visceral fat, they could be considered a sensitive marker of fat redistribution in HIV-infected children.


Assuntos
Tecido Adiposo/anatomia & histologia , Tecido Adiposo/efeitos dos fármacos , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Distribuição da Gordura Corporal , Infecções por HIV/tratamento farmacológico , Resistina/sangue , Tecido Adiposo/metabolismo , Adolescente , Adulto , Animais , Antropometria , Criança , Inibidores da Protease de HIV/uso terapêutico , Humanos , Lipodistrofia/induzido quimicamente
7.
AIDS Care ; 19(6): 764-6, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17573596

RESUMO

Adherence to antiretroviral (ART) therapy, as reported by children caregivers, was investigated and compared with physicians' estimates of adherence. Two parallel structured questionnaires were administered to caregivers of 129 HIV-infected children and to their physicians in seven different Italian reference centers. Doses omitted in the last four days were recorded. Perfect adherence (>95% of prescribed doses taken in the last four days before interview) was reported by caregivers of 103 (79%) children. Five children (5%) omitted one dose of any ART drug in four days and were considered adherent. Low (<95 but >80% of doses) and poor (<80% of doses) adherence were reported by 15 (12%) and six (5%) caregivers, respectively. Forty-eight children (37%) were judged to be non-adherent by their physicians, including 35 children who were receiving all the prescribed doses according to caregivers. The physicians identified eight out of the 21 non-adherent children as adherent. Non-adherence estimates by physicians closely correlated with poor clinical conditions. These data indicate that adherence is a major problem but there is a clear discrepancy between caregiver reports and physician judgement. The results underline the need of close surveillance of adherence in HIV-positive children in order to evaluate the effectiveness of ART therapy.


Assuntos
Antirretrovirais/administração & dosagem , Cuidadores/normas , Infecções por HIV/tratamento farmacológico , Entrevistas como Assunto/métodos , Corpo Clínico , Terapia Antirretroviral de Alta Atividade , Criança , Pré-Escolar , Estudos de Avaliação como Assunto , Feminino , Infecções por HIV/psicologia , Humanos , Lactente , Masculino , Cooperação do Paciente/estatística & dados numéricos
8.
Aliment Pharmacol Ther ; 24(2): 387-94, 2006 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16842466

RESUMO

BACKGROUND: There is conflicting evidence as to whether ursodeoxycholic acid (UDCA) reduces the incidence of parenteral nutrition-associated cholestasis. AIM: To investigate the efficacy of UDCA on parenteral nutrition-associated cholestasis in children with intestinal failure due to short bowel syndrome or to other causes. METHODS: Children with cholestasis received 30 mg/kg/day UDCA. Improvement or normalization of parenteral nutrition-associated cholestasis was evaluated at 6 months of therapy and at the last follow-up. In a subgroup of children, serum UDCA levels were measured while receiving UDCA and after 4 weeks withdrawal. RESULTS: Twelve children were treated with UDCA. Full remission or partial improvement of parenteral nutrition-associated cholestasis occurred in 11 of 12 children. In three of four children, withdrawal of UDCA was associated with a rebound rise of cholestasis. Only one of 12 treated children showed no improvement and in this patient, in contrast to four other patients, plasma levels of UDCA did not increase during treatment. CONCLUSIONS: Ursodeoxycholic acid was effective in controlling parenteral nutrition-associated cholestasis. The efficacy of UDCA also in children with short bowel is related to intestinal absorption.


Assuntos
Colagogos e Coleréticos/uso terapêutico , Colestase/tratamento farmacológico , Enteropatias/terapia , Nutrição Parenteral/efeitos adversos , Ácido Ursodesoxicólico/uso terapêutico , Colestase/etiologia , Humanos , Lactente , Recém-Nascido , Enteropatias/sangue , Resultado do Tratamento , Ácido Ursodesoxicólico/sangue
9.
Dig Liver Dis ; 38 Suppl 2: S283-7, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17259092

RESUMO

It is becoming clear that intestinal microflora plays an important role in the development of local and systemic immune response. Nutritional ingredients have been added to infant formula in an attempt to make its composition similar to that of human milk. The effects of these modifications have been observed in the composition of intestinal microflora. Prebiotics are non-digestible foods able to selectively stimulate the growth/activity of a limited number of colonic bacteria. A mixture of galacto-oligosaccharides and fructo-oligosaccharides (GOS/FOS) induces an increase in Bifidobacteria, similar to that of breast-fed infants. What is less clear is whether the modifications of intestinal microflora obtained by functional foods are associated with clinically measurable effects. Preliminary indirect data suggest that increasing the load of Bifidobacteria and Lactobacilli may protect from infections and allergies and this effect may persists beyond infancy. The emerging concept is that early nutritional intervention may be effective in modifying the intestinal microflora composition in a phase in which microbiological imprinting may drive immunological imprinting thereby producing clinical effects. Further investigations and well designed randomised clinical trials are needed to demonstrate the potential beneficial effects and to exclude the potential side effects.


Assuntos
Intestinos/imunologia , Intestinos/microbiologia , Probióticos/farmacologia , Bifidobacterium/fisiologia , Humanos , Lactente , Lactobacillus/fisiologia
10.
Aliment Pharmacol Ther ; 20(7): 813-9, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15379842

RESUMO

AIMS: To assess the incidence of intestinal inflammation in children with cystic fibrosis and to investigate whether probiotics decrease it. STUDY DESIGN: In this two-phase, controlled, prospective study, faecal calprotectin was measured by enzyme-linked immunosorbent assay in 30 children with cystic fibrosis, 30 healthy controls and 15 children with active inflammatory bowel disease. Ten children with cystic fibrosis received Lactobacillus GG, and faecal calprotectin was re-measured 4 weeks later. Rectal nitric oxide production was measured with the rectal dialysis bag technique in 20 children with cystic fibrosis, 20 healthy controls and 15 children with inflammatory bowel disease. Five children with cystic fibrosis received Lactobacillus GG and nitric oxide was re-measured 4 weeks later. RESULTS: Mean faecal calprotectin was significantly higher in the two groups of patients than in controls. Abnormal values were detected in 27 of 30 cystic fibrosis and in 15 of 15 inflammatory bowel disease children. Also mean nitric oxide production was increased in both group of patients, and abnormal values were detected in 19 of 20 cystic fibrosis and in 15 of 15 inflammatory bowel disease children. Calprotectin and nitric oxide concentrations were reduced after probiotics administration. CONCLUSIONS: Intestinal inflammation is a major feature of cystic fibrosis and is reduced by probiotics. The latter finding suggests that intestinal microflora play a major role in intestinal inflammation in cystic fibrosis children.


Assuntos
Fibrose Cística/complicações , Doenças Inflamatórias Intestinais/etiologia , Probióticos/uso terapêutico , Estudos de Casos e Controles , Criança , Fezes/química , Feminino , Humanos , Doenças Inflamatórias Intestinais/dietoterapia , Complexo Antígeno L1 Leucocitário/análise , Masculino , Óxido Nítrico/metabolismo , Estudos Prospectivos , Reto/metabolismo
11.
Acta Paediatr ; 92(3): 398-401, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12725560

RESUMO

UNLABELLED: This study reports the first paediatric case of acute inflammatory demyelinating polyradiculoneuropathy (AIDP) associated with a fatal haemophagocytic lymphohistiocytosis (HLH). The patient developed progressive weakness of the lower limbs in the context of a picture of infectious mononucleosis and Epstein-Barr virus (EBV) infection. After an apparent improvement, a fulminant hepatic failure and pancytopenia ensued, leading to death. Molecular genetic studies documented a compound heterozygosity for two mutations in the perforin (PRF1) gene as the background defect for a familial haemophagocytic lymphohistiocytosis (FHL). CONCLUSION: In this patient EBV infection triggered both AIDP and FHL. The latter condition was due to PRF1 deficiency. Two novel mutations in the PRF1 gene were concomitantly present in the patient. The first caused an amino acid change, while the second introduced a stop codon in the sequence which resulted in a truncated protein.


Assuntos
Síndrome de Guillain-Barré/etiologia , Síndrome de Guillain-Barré/genética , Histiocitose de Células não Langerhans/complicações , Histiocitose de Células não Langerhans/genética , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , Criança , Evolução Fatal , Síndrome de Guillain-Barré/diagnóstico , Histiocitose de Células não Langerhans/diagnóstico , Humanos , Masculino , Perforina , Proteínas Citotóxicas Formadoras de Poros
12.
Acta Paediatr ; 92(12): 1398-402, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14971789

RESUMO

AIM: To investigate rates and determinants of adherence to antiretroviral therapy in Italian children infected with the human immunodeficiency virus (HIV). METHODS: An observational, cross-sectional multicentre study was performed through a structured interview with the caregivers of HIV-infected children. The interview included quantitative information on adherence in the 4 d before interview. Sociodemographic, clinical and psychosocial characteristics of children were recorded. RESULTS: 129 children (median age 96 mo) were enrolled, of whom 94 were on highly active antiretroviral therapy (HAART). Twenty-one (16%) omitted more than 5% of total doses in 4 d and were considered non-adherent. However, only 11% of caregivers reported that therapy had been administered at the correct times. No significant difference was found between age and the stage of HIV infection. Children aware of their HIV status were less adherent. Individual drugs showed a broad adherence pattern and children who received HAART were more adherent. Children receiving therapy from foster parents were more adherent than those receiving drugs from biological parents or relatives. CONCLUSIONS: Adherence is a major problem in children. Psychological rather than clinical or sociodemographic features and types of drug are major determinants of adherence.


Assuntos
Antirretrovirais/uso terapêutico , Infecções por HIV/tratamento farmacológico , Adolescente , Cuidadores , Criança , Pré-Escolar , Estudos Transversais , Humanos , Lactente , Entrevistas como Assunto , Itália , Cooperação do Paciente
13.
Aliment Pharmacol Ther ; 15(10): 1619-25, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11564002

RESUMO

BACKGROUND: Nutrient malabsorption is a negative prognostic factor in acquired immunodeficiency syndrome and recent studies have shown that pancreatic insufficiency is a codetermining factor of malabsorption. AIMS: To evaluate the effectiveness of open-label oral pancreatic enzyme supplementation therapy in acquired immunodeficiency syndrome patients with fat malabsorption. PATIENTS AND METHODS: Twenty-four consecutive patients with human immunodeficiency virus infection and fat malabsorption were recruited (11 males, 13 females; median age, 9.1 years). Faecal fat loss was evaluated by steatocrit assay at entry to the study (T-0), after 2 weeks (T-1) without pancreatic enzyme treatment and after a further 2 weeks (T-2) of treatment with pancreatic extracts (Creon 10 000 at a dose of 1000 units of lipase per gram of ingested dietary fat). Faecal elastase-1 and chymotrypsin were assayed at entry. RESULTS: Six patients (25%) had abnormally low elastase-1 and/or chymotrypsin faecal concentration. In all patients, steatocrit values were elevated at both T-0 and T-1. Five patients proved intolerant to pancreatic enzyme treatment because of the onset of abdominal pain, and therapy was discontinued. In the 19 patients who concluded the study, steatocrit values during pancreatic enzyme treatment (T-2) were significantly lower than at entry (P < 0.0001). At T-2, in eight of 19 patients, steatocrit values were within the normal limit and the frequency of cases cured or improved on pancreatic enzyme therapy (at T-2) was significantly higher than that observed during the previous study period without enzyme treatment (T-1) (P < 0.01). A positive significant correlation was found between steatocrit values at entry and the Centers for Disease Control class (P < 0.0005); also, the decrease in steatocrit values during pancreatic enzyme therapy (difference between steatocrit value at T-2 and steatocrit value at T-0) positively correlated with the Centers for Disease Control class (P < 0.05). CONCLUSIONS: This pilot, open-label study showed that pancreatic enzyme supplementation therapy is highly effective in reducing faecal fat loss in human immunodeficiency virus-infected patients with nutrient malabsorption. Further double-blind studies must be undertaken to verify these results and, if they are confirmed, pancreatic enzymes can be added to our weapons in the fight against human immunodeficiency virus-associated nutrient malabsorption.


Assuntos
Doença Celíaca/tratamento farmacológico , Gorduras/metabolismo , Infecções por HIV/complicações , Pancrelipase/uso terapêutico , Adolescente , Doença Celíaca/complicações , Criança , Pré-Escolar , Quimotripsina/análise , Insuficiência Pancreática Exócrina/complicações , Fezes/química , Fezes/enzimologia , Feminino , Humanos , Lactente , Absorção Intestinal , Masculino , Elastase Pancreática/análise , Testes de Função Pancreática , Resultado do Tratamento
14.
Acta Paediatr ; 90(6): 601-4, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11440089

RESUMO

ORS has led to improved outcome of acute gastroenteritis in both industrialised and developing countries. In both settings there is an increasing demand for active therapy to reduce the duration of diarrhoea and its complications. Persistent diarrhoea is a major consequence of intestinal infections and is responsible for a high number of deaths in poor countries. Bismuth subsalicylate has been used for treatment of acute diarrhoea, with preliminary promising results. In this issue of Acta Paediatrica, a trial with BSS is essential. However the results were marginal and did not justify a mass scale use of BSS, also because of poor cost efficacy rate.


Assuntos
Bismuto/uso terapêutico , Gastroenterite/tratamento farmacológico , Compostos Organometálicos/uso terapêutico , Soluções para Reidratação/uso terapêutico , Salicilatos/uso terapêutico , Doença Aguda , Pré-Escolar , Diarreia/tratamento farmacológico , Humanos , Lactente
15.
J Pediatr Gastroenterol Nutr ; 32(1): 71-5, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11176329

RESUMO

BACKGROUND: Childhood gastroenteritis is associated with considerable health costs. The natural clay dioctahedral smectite increases intestinal barrier function and is effective against infectious diarrhea in children in developing countries. The purpose of this work was to investigate the efficacy of smectite in Italian children with acute diarrhea of mild to moderate severity. METHODS: A national, prospective, randomized, case-controlled study was performed in collaboration with primary care pediatricians. Children seen by pediatricians for acute gastroenteritis were treated with oral rehydration solution (ORS) alone or ORS with smectite. Parents returned a form in which total duration of diarrhea, incidence of vomiting and fever, persistence of diarrhea for more than 7 days and hospital admissions were recorded. RESULTS: Eight hundred four children with acute diarrhea were randomly assigned to treated or control groups. Administration of smectite was associated with significant reduction of the duration of diarrhea, as judged by stool frequency and consistency. The incidence and duration of vomiting and fever were not different. Diarrhea lasted more than 7 days in 10% of treated and in 18% of control children (P < 0.01). Hospital admission was necessary in seven treated and six control children. No side effects were observed. CONCLUSIONS: Smectite reduces the duration of diarrhea and prevents a prolonged course. It may therefore consistently reduce the costs of gastroenteritis.


Assuntos
Antidiarreicos/uso terapêutico , Diarreia/tratamento farmacológico , Gastroenterite/tratamento farmacológico , Fármacos Gastrointestinais/uso terapêutico , Silicatos , Doença Aguda/terapia , Pré-Escolar , Análise Custo-Benefício , Feminino , Hidratação , Humanos , Lactente , Itália , Masculino , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento
17.
J Pediatr Gastroenterol Nutr ; 28(3): 315-20, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10067735

RESUMO

BACKGROUND: Growth hormone (GH) stimulates intestinal growth and differentiation and promotes water and ion absorption in the rat intestine. Epidermal growth factor has similar effects, which involve tyrosine kinase activity. The effects of growth hormone on ion transport and cell growth and the role of tyrosine kinase in these effects were examined in a human-derived intestinal cell line (Caco-2). METHODS: For transport study, electrical parameters were measured in human intestinal Caco-2 cell monolayers mounted in Ussing chambers. Cell growth was monitored by counting and 3H-thymidine incorporation in the presence and absence of growth hormone. The role of tyrosine kinase was investigated by using its specific inhibitor genistein. RESULTS: The addition of growth hormone induced a rapid, Cl- -dependent, decrease in short-circuit current without affecting tissue conductance, which is consistent with an anion-absorptive effect. Incubation with growth hormone increased cell count by 85% and 3H-thymidine incorporation by 64% versus the count in control specimens. The absorptive and trophic effects of growth hormone were dose-dependent, and the maximum effective concentration was identical for each effect. Genistein blocked the growth hormone effect on ion transport and cell growth. CONCLUSIONS: Growth hormone stimulates ion absorption and cell growth in human enterocytes. Both effects result from a direct growth hormone-enterocyte interaction, and both require tyrosine kinase activity. Growth hormone may have therapeutic potential in intestinal diseases characterized by epithelial atrophy and loss of water and electrolytes.


Assuntos
Divisão Celular/efeitos dos fármacos , Hormônio do Crescimento Humano/farmacologia , Intestinos/efeitos dos fármacos , Transporte de Íons/efeitos dos fármacos , Proteínas Tirosina Quinases/metabolismo , Células CACO-2 , Cloretos/metabolismo , DNA/biossíntese , Condutividade Elétrica , Inibidores Enzimáticos/farmacologia , Genisteína/farmacologia , Humanos , Mucosa Intestinal/metabolismo , Intestinos/citologia , Cinética , Proteínas Tirosina Quinases/antagonistas & inibidores
18.
J Infect Dis ; 178(5): 1373-8, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9780258

RESUMO

Preliminary clinical evidence suggests that Helicobacter pylori may be associated with diarrhea through its vacuolating toxin (VacA). To establish whether VacA induces intestinal secretion, epithelial damage, or both, purified pH-activated VacA was added to Caco-2 cell monolayers mounted in Ussing chambers, and electrical parameters were monitored. Mucosal addition of VacA induced an increase in short circuit current, consistent with enterotoxic effect. The effect was time- and dose-dependent and saturable. It was not found if the toxin was not pH-activated, added to the serosal side, or preheated. In cells preloaded with the Ca2+ buffering compound BAPTA/AM or with the Cl- channel inhibitor 5-nitro-2-3-(3-phenylpropylamino)benzoic acid, short circuit current did not change, indicating that VacA induces activation of Ca2+-dependent Cl- channels. VacA did not show cytopathic effects, as judged by tissue resistance. These results support the hypothesis that H. pylori may be associated with diarrhea through production of VacA.


Assuntos
Proteínas de Bactérias/toxicidade , Toxinas Bacterianas/toxicidade , Citotoxinas/toxicidade , Helicobacter pylori/metabolismo , Intestinos/efeitos dos fármacos , Proteínas de Bactérias/administração & dosagem , Proteínas de Bactérias/biossíntese , Toxinas Bacterianas/administração & dosagem , Toxinas Bacterianas/biossíntese , Transporte Biológico/efeitos dos fármacos , Células CACO-2/efeitos dos fármacos , Citotoxinas/administração & dosagem , Citotoxinas/biossíntese , Relação Dose-Resposta a Droga , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Impedância Elétrica , Humanos , Indicadores e Reagentes/farmacologia , Vacúolos/efeitos dos fármacos
19.
Pediatr Res ; 40(6): 881-7, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8947967

RESUMO

Oral administration of human serum immunoglobulin reduces the duration of diarrhea and of rotaviral excretion in children. To investigate the in vitro effects of immunoglobulin on virus-enterocyte interaction, Caco-2 cells were infected with Rotavirus strain SA11. Immunoglobulin was added prior to and at various times postinfection. Indirect immunofluorescence was performed with an antibody against VP-6 rotaviral antigen. Cell viability and monolayer transepithelial electrical resistance (TEER) were monitored. Immunofluorescence showed a perinuclear distribution in 90% of cells. Rotavirus infection induced a progressive decrease in TEER and a parallel reduction in cell viability, depending on viral load. Preincubation of the virus with immunoglobulin prevented cell infection as judged by immunofluorescence. Immunoglobulin addition to infected cells partially prevented the decrease in TEER and induced a later shift of TEER toward increasing values, suggesting restoration of monolayer's integrity. The efficacy of immunoglobulin depended on its concentration and on the time of its addition. These results indicate that immunoglobulin is effective in preventing infection and in reducing cell damage, through a direct anti-Rotavirus action and may indicate that immunoglobulin should be administered in the early phase of diarrhea, to reduce the severity of Rotavirus infection.


Assuntos
Antígenos Virais , Proteínas do Capsídeo , Imunoglobulinas/farmacologia , Rotavirus/fisiologia , Replicação Viral , Administração Oral , Células CACO-2 , Capsídeo/química , Sobrevivência Celular , Criança , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Imunização Passiva , Imunoglobulinas/administração & dosagem , Imunoglobulinas/sangue , Rotavirus/imunologia , Infecções por Rotavirus/imunologia , Infecções por Rotavirus/terapia
20.
J Infect Dis ; 171(4): 976-83, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7706827

RESUMO

A cell line model to detect enterotoxic effect was used to test fecal specimens of patients with enteric cryptosporidiosis. Fecal samples were obtained from 11 patients with Cryptosporidium diarrhea, and osmotic gap was determined. Caco-2 cell monolayers grown on filters were mounted in Ussing chambers, and electrical parameters were measured before and after the addition of fecal supernatant. A significant increase in short-circuit current was seen in 9 of 11 specimens. The enterotoxic effect was time- and dose-dependent, saturable, and Cl(-)- and Ca(2+)-dependent. Fecal osmotic gap was consistent with secretory diarrhea in the 9 enterotoxin-positive but not in the 2 enterotoxin-negative samples. In conclusion, a cell line model for studying the pathophysiology of enteric cryptosporidiosis was established. Enterotoxic activity was observed in most patients with enteric cryptosporidiosis and was strictly associated with secretory diarrhea.


Assuntos
Colo/fisiologia , Criptosporidiose/parasitologia , Cryptosporidium , Diarreia/parasitologia , Enterotoxinas/toxicidade , Adulto , Animais , Cálcio/fisiologia , Bovinos , Criança , Cloretos/fisiologia , Eletrofisiologia , Fezes/microbiologia , Fezes/parasitologia , Humanos , Mucosa Intestinal/fisiologia , Concentração Osmolar , Células Tumorais Cultivadas
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