RESUMO
OBJECTIVES: Rome criteria were formulated to define functional gastrointestinal disorders (Rome III criteria, 2006) excluding organic diagnoses when alarm symptoms were absent. The aims of the study were to validate the Rome III criteria as to their capacity to differentiate between organic and functional abdominal pain and to assess the role of alarm symptoms in this differentiation. METHODS: During 2 years all of the patients (ages 4-16 years) presenting with recurrent abdominal pain (Apley criteria) and referred to secondary care were included. Clinical diagnoses were based on protocolized evaluation and intervention with 6-month follow-up. Alarm symptoms were registered. Rome III criteria for functional pain syndromes were assigned independently. Descriptive statistical analyses were performed. RESULTS: In 200 patients (87 boys, mean age 8.8 years), organic (17%), functional (40%), combined organic and functional (9%), spontaneous recovery (27%), and other (8%) clinical diagnoses were established. Alarm symptoms were found in 57.5% (organic causes 56%, functional causes 61%). The evaluation for Rome symptom clusters revealed symptoms of irritable bowel syndrome in 27%, functional dyspepsia in 15%, functional abdominal pain in 28%, functional abdominal pain syndrome in 14.5%, and no pain syndrome in 15.5%. Rome diagnoses, based on symptoms and absence of alarm symptoms, predicted functional clinical diagnosis with sensitivity 0.35 (95% confidence interval 0.27-0.43), specificity 0.60 (0.46-0.73), positive predictive value 0.71 (0.61-0.82), and negative predictive value of 0.24 (0.17-0.32). CONCLUSIONS: The Rome III criteria for abdominal pain are not specific enough to rule out organic causes. Alarm symptoms do not differentiate between organic and functional abdominal pain.
Assuntos
Dor Abdominal/diagnóstico , Ansiedade , Dispepsia/diagnóstico , Gastroenteropatias/diagnóstico , Síndrome do Intestino Irritável/diagnóstico , Dor Abdominal/etiologia , Dor Abdominal/psicologia , Adolescente , Ansiedade/epidemiologia , Criança , Pré-Escolar , Dispepsia/complicações , Dispepsia/psicologia , Feminino , Gastroenteropatias/complicações , Gastroenteropatias/psicologia , Humanos , Síndrome do Intestino Irritável/complicações , Síndrome do Intestino Irritável/psicologia , Masculino , Prevalência , Recidiva , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Inquéritos e QuestionáriosRESUMO
UNLABELLED: Recurrent abdominal pain (RAP) in children is generally believed to be functional. In practice, many children with RAP become pain-free with laxative therapy. The aims of the study were to establish the role of (occult) constipation in RAP and to investigate whether patients diagnosed with (occult) constipation could be identified by history and physical examination. During 2 years, all patients (age 4-16 years, secondary referral) fulfilling Apley criteria of RAP were included. After exclusion of gastrointestinal infections and food intolerance, laxatives were advised when pain persisted. (Occult) constipation was defined as 'abdominal pain disappearing with laxative treatment and not reappearing within a 6 month follow up period'; 'occult constipation' was diagnosed in patients who did not fulfil the Rome criteria of constipation. Two hundred children (87 M; median age 8.8 years) were evaluated. (Occult) constipation was found in 92 patients (46 %). Of these, 18 had considerable relief of pain when treated for a somatic cause but experienced complete relief only after laxative measures; they were considered to have two diagnoses. Using multivariate analysis, a simple model was developed with cystitis in past history, early satiety and flatulence as predictors for (occult) constipation. The risk of (occult) constipation ranged from 18/58 if no predictor was present to 4/4 if all three were present. CONCLUSION: Laxatives played a pivotal role in the recovery of patients with RAP. We developed a simple model to identify patients at risk of having (occult) constipation.
Assuntos
Dor Abdominal/etiologia , Constipação Intestinal/complicações , Dor Abdominal/tratamento farmacológico , Adolescente , Criança , Pré-Escolar , Constipação Intestinal/diagnóstico , Constipação Intestinal/tratamento farmacológico , Fezes , Feminino , Humanos , Laxantes/uso terapêutico , Masculino , RecidivaRESUMO
OBJECTIVES: The aim of this study was to investigate whether protozoa can be identified as a cause of recurrent abdominal pain (RAP), and whether protozoan infections can be recognized by a specific clinical presentation. METHODS: For 2 years, all patients (ages 4-16 years) fulfilling the Apley criteria of RAP referred to secondary care were prospectively evaluated for protozoa (Giardia lamblia, Dientamoeba fragilis, Blastocystis hominis) and treated if positive. Re-examination followed at least 10 days after treatment. Disappearance of pain with eradication and a pain-free follow-up of at least 6 months were considered to be indicative of a causal relation with RAP. The predictive value of the characteristics of the pain for protozoan infections was calculated. RESULTS: Of 220 included patients (92 boys, mean age 8.8 years), 215 brought a stool sample; 73 (34%) carried parasites, 10 of whom had 2 parasites, 2 had 3 parasites. Sixty-five patients were treated. Twenty-five (11%) were pain-free after eradication (21 had D fragilis, 8 B hominis, 4 G lamblia), of whom 11 had another infection (2) or constipation (9) as second diagnosis for the pain. Five had recurrence of infection with D fragilis and were again pain-free with eradication. Patients with protozoa as cause of their pain did not show differences with respect to their presentation when compared with patients with an asymptomatic infection and patients without protozoa. CONCLUSIONS: Protozoa were found as the cause of pain in 6% to 11% of children with RAP. These patients did not show a characteristic presentation when compared with patients with other causes of abdominal pain.
Assuntos
Dor Abdominal/etiologia , Enteropatias Parasitárias/fisiopatologia , Infecções por Protozoários/fisiopatologia , Dor Abdominal/epidemiologia , Dor Abdominal/fisiopatologia , Dor Abdominal/prevenção & controle , Adolescente , Adulto , Antiprotozoários/uso terapêutico , Blastocystis hominis/efeitos dos fármacos , Blastocystis hominis/isolamento & purificação , Causalidade , Criança , Pré-Escolar , Estudos de Coortes , Constipação Intestinal/fisiopatologia , Dientamoeba/efeitos dos fármacos , Dientamoeba/isolamento & purificação , Feminino , Seguimentos , Giardia lamblia/efeitos dos fármacos , Giardia lamblia/isolamento & purificação , Hospitais Pediátricos , Humanos , Enteropatias Parasitárias/tratamento farmacológico , Enteropatias Parasitárias/parasitologia , Masculino , Países Baixos/epidemiologia , Estudos Prospectivos , Infecções por Protozoários/tratamento farmacológico , Infecções por Protozoários/parasitologia , Encaminhamento e Consulta , Prevenção Secundária , Índice de Gravidade de Doença , Adulto JovemRESUMO
INTRODUCTION: R&D costs as an element of medicines' pricing play a prominent role in the discussions regarding the affordability of medicine. This paper investigates the details of R&D costs and the potential for reductions. AREAS COVERED: The manuscript focuses on the constitution of R&D costs in relation to medicines' pricing and its potential developments. This manuscript builds on a cost-of-opportunity approach to explore the results of potential changes in drug development and its possible economic, political, and societal impacts. EXPERT OPINION: The cost of capital is the largest cost category that could be affected by authorities. Public institutions can affect these costs by increasing public investments in R&D and reducing the amount of development time that is associated with a high capital need. In order to affect the cost of failure, it is key to understand its drivers. A government taking risks as the funder of early innovation yields an opportunity to introduce an alternative model for medicine development. Next, to control pricing, it is important to adequately reward innovation in order to ensure improved quality of care, access, and affordability of systems. Innovation, high-quality care, access, and affordability require entrepreneurial and changing positions of governments, authorities, public institutions, and the pharmaceutical industry.
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Desenvolvimento de Medicamentos , Indústria Farmacêutica , Custos e Análise de Custo , Custos de Medicamentos , Humanos , Preparações FarmacêuticasRESUMO
The strict intake regimen of cysteamine bitartrate formulations, associated with side effects, is a concern for the treatment compliance in cystinosis therapy. Therefore, there is a need for a cysteamine formulation with an improved pharmacokinetic profile. This study investigated the pharmacokinetics, safety and tolerability of a new sustained-release cysteamine dosage form, PO-001, in healthy volunteers. This was a randomized, investigator-blinded, three-way cross-over study to compare single doses (600 mg) of PO-001 with Cystagon® (immediate-release) and Procysbi® (delayed-release). Collected blood samples were analyzed for plasma cysteamine concentrations and pharmacokinetic parameters were estimated by noncompartmental analysis. In addition, plasma cysteamine concentrations were analyzed using a population pharmacokinetic approach using NONMEM® . Pharmacokinetics showed clear sustained-release characteristics of PO-001 over time with a lower Cmax and longer Tmax compared to Cystagon® and Procysbi® . All treatment-emergent adverse events were of mild severity, with the exception of two subjects who reported moderate severity gastrointestinal problems including vomiting and diarrhea, which were related to Cystagon® intake. Population PK simulations showed a favourable PK profile based on Cmax and Ctrough concentrations at steady state. In conclusion, a single dose of 600 mg PO-001 was well tolerated with no findings of clinical concern. This new cysteamine bitartrate formulation showed pharmacokinetics of a sustained-release formulation, which may be beneficial for the treatment of cystinosis patients. This study supports advancing this type of sustained-release formulation into a subsequent study to confirm reduced dosing frequency with efficient control of white blood cells (WBCs) cystine levels. Netherlands Trial Registry (NTR) (NL67638.056.18).
Assuntos
Cisteamina/farmacocinética , Eliminadores de Cistina/farmacocinética , Cistinose/tratamento farmacológico , Adulto , Área Sob a Curva , Estudos Cross-Over , Cisteamina/administração & dosagem , Cisteamina/efeitos adversos , Eliminadores de Cistina/administração & dosagem , Eliminadores de Cistina/efeitos adversos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/efeitos adversos , Preparações de Ação Retardada/farmacocinética , Voluntários Saudáveis , Humanos , Masculino , Países Baixos , Adulto JovemRESUMO
Mucins are glycoproteins that are common on the surfaces of many epithelial cells; they are deemed to mediate many interactions between these cells and their milieu. Several of these mucins form the mucus layer that is found in many hollow organs. The biophysical properties of mucins are related to their extensive O-linked glycosylation rather than directly to their polypeptide sequences. Despite the frequent absence of sequence homology, many human genes encoding mucins have been named MUC followed by a number, unjustly suggesting the existence of one large gene family. In this article, it is suggested that the mucin genes be renamed according to their sequence homologies.
Assuntos
Células Epiteliais/fisiologia , Mucinas/genética , Animais , Cromossomos/genética , Expressão Gênica , Glicosilação , Humanos , Mucinas/classificação , Mucinas/metabolismo , Família MultigênicaRESUMO
With the assignment of the 500th European Union orphan drug designation in 2007, the Regulation on Orphan Medicinal Products truly begins to show its potential for delivering new medicines to patients with rare diseases. Here, we analysed European orphan drug development at a national level and unveil a strong relationship between orphan drug development and pharmaceutical innovation performance in Europe. Moreover, we identify gaps in transition from science into orphan drug development as important bottlenecks that exist in several European countries. Our findings underline the importance of innovation-based policies to enhance the development of orphan drugs in Europe.
Assuntos
Produção de Droga sem Interesse Comercial , Preparações Farmacêuticas , Aprovação de Drogas/economia , Europa (Continente) , União Europeia , Regulamentação Governamental , Humanos , Legislação de Medicamentos , Produção de Droga sem Interesse Comercial/economia , Preparações Farmacêuticas/economiaRESUMO
Expression of the mucin MUC2, the structural component of the colonic mucus layer, is lowered in ulcerative colitis. Furthermore, interleukin (IL)-10 knockout (IL-10-/-) mice develop colitis and have reduced Muc2 levels. Our aim was to obtain insight into the role of Muc2 and IL-10 in epithelial protection. Muc2-IL-10 double-knockout (Muc2/IL-10(DKO)) mice were characterized and compared to Muc2 knockout (Muc2-/-), IL-10-/- and wild-type (WT) mice. Clinical symptoms, intestinal morphology and differences in epithelial-specific protein levels were analyzed. In addition, levels of the pro-inflammatory cytokines in colonic tissue and serum were determined. IL-10-/- mice were indistinguishable from WT mice throughout this experiment and showed no clinical or histological signs of colitis. Muc2/IL-10(DKO) and Muc2-/- mice showed significant growth retardation and clinical signs of colitis at 4 and 5 weeks, respectively. Muc2/IL-10(DKO) mice had a high mortality rate (50% survival/5 weeks) compared to the other types of mice (100% survival). Microscopic analysis of the colon of Muc2/IL-10(DKO) mice showed mucosal thickening, increased proliferation, superficial erosions and a diminished Muc4 expression. Furthermore, pro-inflammatory cytokines were significantly upregulated, both in tissue (mRNA) and systemically in Muc2/IL-10(DKO) mice. In conclusion, Muc2/IL-10(DKO) mice develop colitis, which is more severe in every aspect compared to Muc2-/- and IL-10-/- mice. These data indicate that (i) in case of Muc2 deficiency, the anti-inflammatory cytokine IL-10 can control epithelial damage, though to a limited extent and (ii) the mucus layer is most likely a key factor determining colitis.
Assuntos
Epitélio/imunologia , Fatores Imunológicos/metabolismo , Inflamação/etiologia , Interleucina-10/deficiência , Mucinas/deficiência , Animais , Colite/metabolismo , Colite/patologia , Colo/metabolismo , Colo/patologia , Citocinas/sangue , Citocinas/metabolismo , Modelos Animais de Doenças , Epitélio/patologia , Heterozigoto , Imuno-Histoquímica , Inflamação/patologia , Interleucina-10/genética , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Camundongos , Camundongos Knockout , Mucina-2 , Mucinas/genéticaRESUMO
OBJECTIVES: To evaluate the impact on career development of a program for scientific training of Dutch medical students in an American academic division for pediatric gastroenterology and nutrition. MATERIALS AND METHODS: A survey was undertaken of medical students who were trained in the division of pediatric gastroenterology and nutrition at Tufts University and later at Children's Hospital, Harvard Medical School, Boston, MA. Characteristics of the students, the training period, the scientific output, and their career development were evaluated. RESULTS: A questionnaire was sent to 54 students, of which 39 (72%) responded. The mean time of their rotation was 12.2 +/- 12.1 months. Twenty-five students published 33 scientific manuscripts. Fifteen students obtained a doctorate degree and 4 are involved in a doctorate program. Six theses were directly related to the scientific content of the rotation and were performed under the supervision of American mentors. A total of 59% of the students hold a position as medical specialist, which is a substantially higher percentage than the national average of all graduated medical doctors. Thirty-five percent of them practice pediatrics (of whom 38% practice pediatric gastroenterology) and 22% practice gastroenterology. Seventy-eight percent of the medical specialists hold an academic position. CONCLUSIONS: Dutch medical students who are scientifically trained in a US academic division for pediatric gastroenterology and nutrition--where specialists approached all of the students with a special program to involve them in biomedical research--have a great chance to establish a scientific career track and to become a medical specialist.
Assuntos
Escolha da Profissão , Educação de Pós-Graduação em Medicina , Medicina , Pediatria/educação , Especialização , Estudantes de Medicina/psicologia , Adulto , Bolsas de Estudo , Feminino , Gastroenterologia/educação , Humanos , Internato e Residência , Masculino , Países Baixos , Ciências da Nutrição/educação , Editoração , Pesquisa , Estudantes de Medicina/estatística & dados numéricos , Inquéritos e Questionários , Estados UnidosRESUMO
OBJECTIVE: To encourage the development of drugs for rare diseases, orphan drug legislation has been introduced in the USA (1983) and in the EU (2000). Recent literature discusses factors that may influence the development of new orphan medicinal products in the EU. This study aims to identify predictors for successful marketing authorisation of potential orphan drugs in the EU. METHODS: A comparison between randomly selected authorised and a matched sample of not-yet-authorised orphan drug designations has been performed. Determinants in the study included characteristics of the indication, of the product and of the sponsor. Data were collected from the public domain only. RESULTS: Orphan drug approval was strongly associated with previous experience of the sponsor in obtaining approval for another orphan drug (OR = 17.3, 95% CI = 5.6-53.1). Furthermore, existing synthetic entities compared to biotechnology products tended to have a higher likelihood of reaching approval status (OR = 3.9, 95% CI = 0.9-16.6). CONCLUSION: This study showed that experience of a company in developing orphan drugs is an important predictor for subsequent authorisation of other orphan drugs. The same applies for existing (synthetic) molecules, for which much knowledge is available. Further research should be directed towards studying the quality of the clinical development program of those designated orphan medicinal products not reaching approval status.
Assuntos
Aprovação de Drogas/estatística & dados numéricos , Indústria Farmacêutica/estatística & dados numéricos , Produção de Droga sem Interesse Comercial , Doenças Raras/tratamento farmacológico , Aprovação de Drogas/legislação & jurisprudência , Indústria Farmacêutica/legislação & jurisprudência , União Europeia , Humanos , Prevalência , Doenças Raras/epidemiologiaRESUMO
Cyclooxygenases (COXs) play a significant role in many different viral infections with respect to replication and pathogenesis. Here we investigated the role of COXs in the mouse hepatitis coronavirus (MHV) infection cycle. Blocking COX activity by different inhibitors or by RNA interference affected MHV infection in different cells. The COX inhibitors reduced MHV infection at a post-binding step, but early in the replication cycle. Both viral RNA and viral protein synthesis were affected with subsequent loss of progeny virus production. Thus, COX activity appears to be required for efficient MHV replication, providing a potential target for anti-coronaviral therapy.
Assuntos
Vírus da Hepatite Murina/crescimento & desenvolvimento , Prostaglandina-Endoperóxido Sintases/fisiologia , Replicação Viral/fisiologia , Células CACO-2 , Inibidores de Ciclo-Oxigenase/farmacologia , Humanos , Isoenzimas/biossíntese , Isoenzimas/genética , Isoenzimas/fisiologia , Prostaglandina-Endoperóxido Sintases/biossíntese , Prostaglandina-Endoperóxido Sintases/genética , Interferência de RNA , RNA Viral/biossíntese , Proteínas Virais/biossínteseRESUMO
Chemotherapy-induced intestinal damage is a very important dose-limiting side effect for which there is no definitive prophylaxis or treatment. This is in part due to the lack of understanding of its pathophysiology and impact on intestinal differentiation. The objective of this study was to investigate the gene expression of the small intestinal transcription factors HNF-1alpha, Cdx2, GATA-4 in an experimental model of methotrexate (MTX)-induced intestinal damage, and to correlate these alterations with histological damage, epithelial proliferation and differentiation. HNF-1alpha, Cdx2 and GATA-4 are critical transcription factors in epithelial differentiation, and in combination they act as promoting factors of the sucrase-isomaltase (SI) gene, an enterocyte-specific differentiation marker which is distinctly downregulated after MTX treatment. Mice received two doses of MTX i.v. on two consecutive days and were sacrificed 1, 3 and 7 or 9 days after final injection. Segments of the jejunum were taken for morphological, immunohistochemical and quantitative analyses. Intestinal damage was most severe at day 3 and was associated with decreased expression of the transcriptional factors HNF-1alpha, Cdx2 and GATA-4, which correlated well with decreased expression of SI, and seemed inversely correlated with enhanced proliferation of epithelial crypt cells. During severe damage, the epithelium was preferentially concerned with proliferation rather than differentiation, most likely in order to restore the small intestinal barrier function rather than maintaining its absorptive function. Since HNF-1alpha, Cdx2 and GATA-4 are critical for intestine-specific gene expression and therefore crucial in epithelial differentiation, these results may explain, at least in part, why intestinal differentiation is compromised during MTX treatment.
Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Mucosa Intestinal/efeitos dos fármacos , Metotrexato/farmacologia , Animais , Fator de Transcrição CDX2 , Fator de Transcrição GATA4/metabolismo , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Proteínas de Homeodomínio/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Jejuno/efeitos dos fármacos , Jejuno/metabolismo , Jejuno/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Complexo Sacarase-Isomaltase/metabolismo , Transativadores/metabolismoRESUMO
OBJECTIVE: We determined incidences of underfeeding and overfeeding in children who were admitted to a multidisciplinary tertiary pediatric intensive care and evaluated the usefulness of the respiratory quotient (RQ) obtained from indirect calorimetry to assess feeding adequacy. METHODS: Children 18 y and younger who fulfilled the criteria for indirect calorimetry entered our prospective, observational study and were studied until day 14. Actual energy intake was recorded, compared with required energy intake (measured energy expenditure plus 10%), and classified as underfeeding (<90% of required), adequate feeding (90% to 110% of required), or overfeeding (>110% of required). We also evaluated the adequacy of a measured RQ lower than 0.85 to identify underfeeding, and an RQ higher than 1.0 to identify overfeeding. RESULTS: Ninety-eight children underwent 195 calorimetric measurements. Underfeeding, adequate feeding, and overfeeding occurred on 21%, 10%, and 69% of days, respectively. An RQ lower than 0.85 to identify underfeeding showed low sensitivity (63%), high specificity (89%), and high negative predictive value (90%). An RQ higher than 1.0 to indicate overfeeding showed poor sensitivity (21%), but a high specificity (97%) and a high positive predictive value (93%). Food composition, notably high-carbohydrate intake, was responsible for an RQ exceeding 1.0 in the overfed group. CONCLUSION: Children admitted to the intensive care unit receive adequate feeding on only 10% of measurement days during the first 2 wk of admission. The usefulness of RQ to monitor feeding adequacy is limited to identifying (carbohydrate) overfeeding and excluding underfeeding.
Assuntos
Calorimetria Indireta/métodos , Transtornos da Nutrição Infantil/diagnóstico , Estado Terminal/terapia , Ingestão de Energia/fisiologia , Apoio Nutricional , Consumo de Oxigênio/fisiologia , Adolescente , Gasometria , Dióxido de Carbono/metabolismo , Criança , Pré-Escolar , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/metabolismo , Metabolismo Energético/fisiologia , Feminino , Humanos , Lactente , Recém-Nascido , Unidades de Terapia Intensiva Pediátrica , Masculino , Apoio Nutricional/efeitos adversos , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e EspecificidadeRESUMO
The nucleotide sequence of the pMS1 clone was submitted to the GenBank Nucleotide Sequence Database under accession number AF288076. Changes in the expression of mucin genes in gastrointestinal cancers is thought to contribute to the development of the disease. In our laboratory we have shown previously that MUC5AC is aberrantly expressed in rectosigmoid villous adenomas. However, the regulatory mechanisms underlying that altered profile of expression is unknown. In order to study its regulation at the transcriptional level, we have isolated and characterized 5.5 kb of the 5'-flanking region of the mouse Muc5ac mucin gene. The promoter is flanked by a TATA box and a transcriptional start site is located 22 bp downstream of the TATA box. Analysis of the sequence showed a high density of binding sites for Smad4, an essential factor in the signalling cascade activated by TGF-beta (transforming growth factor-beta), and Sp1, an important factor in the regulation of MUC5AC. This led us to study Muc5ac regulation by TGF-beta. We show that exogenous addition of TGF-beta to the cells induces Muc5ac endogenous expression, promoter activity and Smad4 binding to the promoter. By co-transfection studies we show that Smad4 is essential for Muc5ac promoter activation and that it does not synergize with Smad2 or Smad3. By gel-retardation and co-transfection assays, we identified Sp1 and Sp3 as important regulators of Muc5ac expression and showed that Smad4 and Sp1 act in a co-operative manner to transactivate Muc5ac promoter activity. Altogether these results bring new insights into the molecular mechanisms of TGF-beta-mediated up-regulation of Muc5ac and enhance our understanding as to how Muc5ac is regulated in certain pathologies of the gastrointestinal tract.
Assuntos
Mucinas Gástricas/genética , Mucinas/química , Mucinas/genética , Neoplasias Epiteliais e Glandulares/genética , Ativação Transcricional/genética , Região 5'-Flanqueadora/genética , Sequência de Aminoácidos/genética , Animais , Sequência de Bases/genética , Linhagem Celular , Linhagem Celular Tumoral , Clonagem Molecular , Proteínas de Ligação a DNA/fisiologia , Mucinas Gástricas/química , Mucinas Gástricas/fisiologia , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/fisiologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Mucina-5AC , Mucinas/fisiologia , Neoplasias Epiteliais e Glandulares/patologia , Especificidade de Órgãos/genética , Regiões Promotoras Genéticas , Ratos , Proteína Smad4 , Fator de Transcrição Sp1/fisiologia , Fator de Transcrição Sp3 , Transativadores/fisiologia , Fatores de Transcrição/fisiologia , Sítio de Iniciação de Transcrição , Fator de Crescimento Transformador beta/fisiologiaRESUMO
BACKGROUND: Glucose is a major oxidative substrate for intestinal energy generation in neonatal animals; however, few data in preterm infants are available. Early administration of enteral nutrition, including glucose, may be an effective strategy to support intestinal adaptation to extrauterine life in preterm neonates. OBJECTIVE: The purpose of the present study was to quantify the first-pass uptake and oxidation of glucose by the splanchnic tissues (intestine and liver) in human neonates. DESIGN: Eight preterm infants [birth weight ( +/- SD): 1.19 +/- 0.22 kg, gestational age: 29 +/- 1 wk] were studied while they received 2 different enteral intakes (A: 40% enteral, 60% parenteral, total glucose intake = 7.5 +/- 0.5 mg. kg(-1). min(-1), and B: 100% enteral, total glucose intake = 7.8 +/- 0.4 mg. kg(-1). min(-1)). Splanchnic and whole-body glucose kinetics were measured by use of dual-tracer techniques. RESULTS: During both feeding periods, approximately one-third of dietary glucose intake was utilized during the first pass by the splanchnic tissues. More than three-quarters of this utilized glucose was oxidized in both periods (79 +/- 36% with A and 84 +/- 45% with B). Whole-body glucose oxidation was substantial under both circumstances: 72 +/- 5% and 77% +/- 6% of the glucose flux was oxidized during partial (A) and full (B) enteral feeding, respectively. CONCLUSIONS: Approximately one-third of dietary glucose is utilized during the first pass by the splanchnic tissues, irrespective of the dietary intake. Most of the utilized glucose is used for energy generation.
Assuntos
Nutrição Enteral , Glucose/farmacocinética , Recém-Nascido Prematuro/metabolismo , Circulação Esplâncnica/fisiologia , Adaptação Fisiológica , Isótopos de Carbono , Feminino , Glucose/administração & dosagem , Glucose/metabolismo , Humanos , Alimentos Infantis , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Absorção Intestinal , Masculino , Espectrometria de Massas , Oxirredução , Nutrição ParenteralRESUMO
The rapidly dividing small intestinal epithelium is very sensitive to the cytostatic drug methotrexate. We investigated the regulation of epithelial gene expression in rat jejunum during methotrexate-induced damage and regeneration. Ten differentiation markers were localized on tissue sections and quantified at mRNA and protein levels relative to control levels. We analyzed correlations in temporal expression patterns between markers. mRNA expression of enterocyte and goblet cell markers decreased significantly during damage for a specific period. Of these, sucrase-isomaltase (-62%) and CPS (-82%) were correlated. Correlations were also found between lactase (-76%) and SGLT1 (-77%) and between I-FABP (-52%) and L-FABP (-45%). Decreases in GLUT5 (-53%), MUC2 (-43%), and TFF3 (-54%) mRNAs occurred independently of any of the other markers. In contrast, lysozyme mRNA present in Paneth cells increased (+76%). At the protein level, qualitative and quantitative changes were in agreement with mRNA expression, except for Muc2 (+115%) and TFF3 (+81%), which increased significantly during damage, following independent patterns. During regeneration, expression of each marker returned to control levels. The enhanced expression of cytoprotective molecules (Muc2, TFF3, lysozyme) during damage represents maintenance of goblet cell and Paneth cell functions, most likely to protect the epithelium. Decreased expression of enterocyte-specific markers represents decreased enterocyte function, of which fatty acid transporters were least affected.
Assuntos
Antimetabólitos Antineoplásicos/efeitos adversos , Mucosa Intestinal/efeitos dos fármacos , Jejuno/efeitos dos fármacos , Metotrexato/efeitos adversos , RNA Mensageiro/metabolismo , Animais , Biomarcadores , Enterócitos/metabolismo , Células Caliciformes/metabolismo , Imuno-Histoquímica , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Jejuno/metabolismo , Jejuno/patologia , Masculino , Ratos , RegeneraçãoRESUMO
BACKGROUND: In children with inflammatory bowel disease (IBD), treatment depends on the type and extent of disease. Therefore, maximal effort should be made to provide a correct diagnosis. The aim of this study was to assess the value of a histologic diagnosis made on the basis of either ileal and colonic or rectosigmoid biopsies. METHODS: In 42 children with a known diagnosis of IBD, biopsies from rectum and sigmoid were reassessed by an expert, blinded pathologist. This histologic diagnosis was compared with the diagnosis based on (ileo)colonic biopsies and the final diagnosis. RESULTS: In patients with IBD, diagnostic accuracy of rectosigmoid histology was 0.4524. For (ileo)colonic biopsies, diagnostic accuracy was 0.7619. CONCLUSIONS: Histology on biopsies from rectum and sigmoid is insufficient for a correct diagnosis of Crohn's disease or ulcerative colitis in children. At initial presentation, an ileocolonoscopy with biopsies should therefore be performed in all children.
Assuntos
Biópsia por Agulha , Colo Sigmoide/patologia , Colo/patologia , Colonoscopia , Íleo/patologia , Doenças Inflamatórias Intestinais/patologia , Reto/patologia , Adolescente , Fatores Etários , Criança , Pré-Escolar , Colo/diagnóstico por imagem , Colo Sigmoide/diagnóstico por imagem , Feminino , Humanos , Íleo/diagnóstico por imagem , Lactente , Doenças Inflamatórias Intestinais/diagnóstico por imagem , Masculino , Radiografia , Reto/diagnóstico por imagem , Reprodutibilidade dos TestesRESUMO
Germ-free (GF) interleukin 10-deficient (IL-10) mice develop chronic colitis after colonization by normal enteric bacteria. Muc2 is the major structural component of the protective colonic mucus. Our aim was to determine whether primary or induced aberrations in Muc2 synthesis occur in GF IL-10 mice that develop colitis after bacterial colonization. GF IL-10 and wild-type mice were colonized with commensal bacteria for various intervals up to 6 weeks. Colitis was quantified by histologic score and IL-12 secretion. Muc2 synthesis, total level of Muc2, and Muc2 sulfation were measured quantitatively. GF IL-10 mice showed 10-fold lower Muc2 synthesis and Muc2 levels compared with GF wild-type mice, but Muc2 sulfation was not different. When bacteria were introduced, IL-10 mice developed colitis, whereas wild-type mice remained healthy. Muc2 synthesis was unchanged in wild-type mice, but IL-10 mice showed a peak increase in Muc2 synthesis 1 week after bacterial introduction, returning to baseline levels after 2 weeks. Total Muc2 levels decreased 2-fold in wild-type mice but remained at stable low levels in IL-10 mice. Upon introducing bacteria, Muc2 sulfation increased 2-fold in wild-type mice, whereas in IL-10 mice Muc2 sulfation decreased 10-fold. In conclusion, a primary defect in colonic Muc2 synthesis is present in IL-10 mice, whereas bacterial colonization and colitis in these mice led to reduced Muc2 sulfation. These quantitative and structural aberrations in Muc2 in IL-10 mice likely reduce the ability of their mucosa to cope with nonpathogenic commensal bacteria and may contribute to their susceptibility to develop colitis.
Assuntos
Colite Ulcerativa/microbiologia , Interleucina-10/deficiência , Mucinas/biossíntese , Animais , Bactérias/patogenicidade , Northern Blotting , Colite Ulcerativa/genética , Colite Ulcerativa/patologia , Interleucina-10/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Mucina-2 , Mucinas/genética , RNA Mensageiro/análise , Organismos Livres de Patógenos Específicos , Fator Trefoil-3RESUMO
The physician treating children with inflammatory bowel disease is confronted with a number of specific problems, one of them being the lack of randomized, controlled drug trials in children. In this review, the role of nutritional therapy is discussed with a focus on primary treatment, especially for children with Crohn's disease. Then, the available medical therapies are highlighted, reviewing the evidence of effectiveness and side effects in children, as compared with what is known in adults. Nutritional therapy has proven to be effective in inducing and maintaining remission in Crohn's disease while promoting linear growth. Conventional treatment consists of aminosalicylates and corticosteroids, whereas the early introduction of immunosuppressives (such as azathioprine or 6-mercaptopurine) is advocated as maintenance treatment. If these drugs are not tolerated or are ineffective, methotrexate may serve as an alternative in Crohn's disease. Cyclosporine is an effective rescue therapy in severe ulcerative colitis, but only will postpone surgery. A novel strategy to treat Crohn's disease is offered by infliximab, a monoclonal antibody to the proinflammatory cytokine tumor necrosis factor (TNF)-alpha. Based on the best-available evidence, suggested usage is provided for separate drugs with respect to dosage and monitoring of side effects in children.
Assuntos
Medicina Baseada em Evidências , Doenças Inflamatórias Intestinais/dietoterapia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Adulto , Fatores Etários , Criança , HumanosRESUMO
The origin of gastric metaplasia of the duodenum (GMD) remains enigmatic. We studied expression of mucins and trefoil peptides in GMD to gain insight into its phenotype and origin. We examined duodenal tissue of 95 patients (0 to 83 years old, 26 with gastric Helicobacter pylori infection) for the presence of GMD. Expression was examined immunohistochemically of secretory mucins (MUC2, MUC5AC, MUC5B, and MUC6), trefoil peptides (TFF1, TFF2, and TFF3), and sucrase-isomaltase (SI). GMD, found in 37 patients, correlated positively to gastric H. pylori infection, age, and villus atrophy. MUC2 and TFF3, expressed in normal goblet cells, were absent from 100% and 87% of GMD, respectively. GMD ubiquitously expressed MUC5AC, whereas MUC5AC expression in adjacent goblet cells was closely correlated with the extent of GMD. TFF1, TFF2, and MUC6 were found in 84%, 92%, and 65% of GMD, respectively. MUC5B was absent from epithelium and GMD. SI, expressed by villus enterocytes, was absent from GMD. Brunner's glands ubiquitously expressed MUC5B, MUC6, and TFF2. GMD was characterized by the expression of gastric-type proteins MUC5AC, MUC6, TFF1, and TFF2 and the absence of intestinal markers MUC2, TFF3, and SI. In terms of the location of metaplastic cells, our results suggest that epithelial cells migrating toward villus tips switch to gastric-type secretory cells. Positive correlation with infection suggests an inductive role H. pylori in the development of GMD.