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1.
J Pediatr Gastroenterol Nutr ; 61(4): 384-92, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26192701

RESUMO

OBJECTIVES: The aim of the study was to determine the prevalence of stressful life events including (sexual) abuse in children with functional defecation disorders by performing a systematic review. METHODS: We searched MEDLINE, EMBASE, and PsycINFO for cohort, case-control and cross-sectional studies investigating the prevalence of stressful life events, including (sexual) abuse in children with functional defecation disorders. RESULTS: The search yielded 946 articles, of which 8 were included with data from 654 children with functional constipation and 1931 children with (constipation-associated) fecal incontinence (FI). Overall, children with functional defecation disorders had been significantly more exposed to stressful life events than healthy children, with prevalence rates ranging from 1.6% to 90.9%. Being bullied, being a relational victim, interruption of toilet training, punishment by parents during toilet training, and hospitalization were significantly related to FI, whereas separation from the best friend, failure in an examination, severe illness in a close family member, loss of job by a parent, frequent punishment, and living in a war-affected area were significantly related to constipation. Only 1 study measured the prevalence of child abuse, which reported a significantly higher prevalence of child (sexual) abuse in children with FI compared with controls. CONCLUSIONS: The prevalence of stressful life events, including (sexual) abuse is significantly higher in children with functional defecation disorders compared with healthy children. To gain more insight into the true prevalence of child (sexual) abuse in children with functional defecation disorders, more studies are clearly needed.


Assuntos
Constipação Intestinal/etiologia , Incontinência Fecal/etiologia , Enteropatias/etiologia , Acontecimentos que Mudam a Vida , Estresse Fisiológico , Estresse Psicológico/fisiopatologia , Criança , Abuso Sexual na Infância/psicologia , Constipação Intestinal/psicologia , Defecação , Incontinência Fecal/psicologia , Humanos , Enteropatias/psicologia , Intestinos/fisiopatologia , Prevalência , Estresse Psicológico/epidemiologia , Estresse Psicológico/psicologia
2.
Lupus Sci Med ; 3(1): e000146, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27099766

RESUMO

OBJECTIVES: To evaluate the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of single-dose and multiple-dose administration of AMG 557, a human anti-inducible T cell co-stimulator ligand (ICOSL) monoclonal antibody, in subjects with systemic lupus erythematosus (SLE). METHODS: Patients with mild, stable SLE (n=112) were enrolled in two clinical trials to evaluate the effects of single (1.8-210 mg subcutaneous or 18 mg intravenous) and multiple (6 -210 mg subcutaneous every other week (Q2W)×7) doses of AMG 557. Subjects received two 1 mg intradermal injections 28 days apart of keyhole limpet haemocyanin (KLH), a neoantigen, to assess PD effects of AMG 557. Safety, PK, target occupancy, anti-KLH antibody responses, lymphocyte subset analyses and SLE-associated biomarkers and clinical outcomes were assessed. RESULTS: AMG 557 demonstrated an acceptable safety profile. The PK properties were consistent with an antibody directed against a cell surface target, with non-linear PK observed at lower concentrations and linear PK at higher concentrations. Target occupancy by AMG 557 was dose dependent and reversible, and maximal occupancy was achieved in the setting of this trial. Anti-AMG 557 antibodies were observed, but none were neutralising and without impact on drug levels. A significant reduction in the anti-KLH IgG response was observed with AMG 557 administration without discernible changes in the anti-KLH IgM response or on the overall IgG levels. No discernible changes were seen in lymphocyte subsets or in SLE-related biomarkers and clinical measures. CONCLUSIONS: The selective reduction in anti-KLH IgG demonstrates a PD effect of AMG 557 in subjects with SLE consistent with the biology of the ICOS pathway and supports further studies of AMG 557 as a potential therapeutic for autoimmune diseases. TRIAL REGISTRATION NUMBERS: NCT02391259 and NCT00774943.

3.
Eur J Hum Genet ; 13(1): 6-25, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15523501

RESUMO

There are no guidelines available for diagnostic studies in patients with mental retardation (MR) established in an evidence-based manner. Here we report such study, based on information from original studies on the results with respect to detected significant anomalies (yield) of six major diagnostic investigations, and evaluate whether the yield differs depending on setting, MR severity, and gender. Results for cytogenetic studies showed the mean yield of chromosome aberrations in classical cytogenetics to be 9.5% (variation: 5.4% in school populations to 13.3% in institute populations; 4.1% in borderline-mild MR to 13.3% in moderate-profound MR; more frequent structural anomalies in females). The median yield of subtelomeric studies was 4.4% (also showing female predominance). For fragile X screening, yields were 5.4% (cytogenetic studies) and 2.0% (molecular studies) (higher yield in moderate-profound MR; checklist use useful). In metabolic investigations, the mean yield of all studies was 1.0% (results depending on neonatal screening programmes; in individual populations higher yield for specific metabolic disorders). Studies on neurological examination all showed a high yield (mean 42.9%; irrespective of setting, degree of MR, and gender). The yield of neuroimaging studies for abnormalities was 30.0% (higher yield if performed on an indicated basis) and the yield for finding a diagnosis based on neuroradiological studies only was 1.3% (no data available on value of negative findings). A very high yield was found for dysmorphologic examination (variation 39-81%). The data from this review allow conclusions for most types of diagnostic investigations in MR patients. Recommendations for further studies are provided.


Assuntos
Deficiência Intelectual/diagnóstico , Aberrações Cromossômicas , Citogenética , Exposição Ambiental , Feminino , Síndrome do Cromossomo X Frágil/diagnóstico , Humanos , Deficiência Intelectual/genética , Masculino , Telômero/genética
4.
J Mol Biol ; 196(2): 433-6, 1987 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-3656454

RESUMO

Following irradiation of human cells with ultraviolet light, DNA repair patches are initially inserted near the 5' and 3' ends of nucleosome core DNA leaving a "gap" in repair synthesis (of approximately 50 bases) near the center of the core DNA. With time, however, these same repair patches become randomized, apparently by nucleosome migration. We have developed both an analytical expression and a computer algorithm (which simulates nucleosome migration along DNA) to determine the average distance nucleosomes must migrate to change the initial, non-uniform distribution of repair patches in nucleosomes to a random distribution. Both of these methods yielded the same result: nucleosomes must migrate an average of about 50 base-pairs in either direction to produce the randomization observed.


Assuntos
Reparo do DNA/efeitos da radiação , Nucleossomos/efeitos da radiação , Movimento Celular/efeitos da radiação , Simulação por Computador , DNA/efeitos da radiação , Humanos , Modelos Biológicos , Software , Raios Ultravioleta
5.
J Mol Biol ; 287(3): 449-57, 1999 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-10092451

RESUMO

Interaction of fd or M13 filamentous phage with a chloroform/water interface induces morphological change, contracting the filaments sequentially into shortened rods (I-forms), and then into spheroidal particles (S-forms). To further investigate this phage contraction, 34 and 26 chloroform-resistant isolates of fd and M13, respectively, were selected after chloroform treatment of wild-type phages at pH 8. 2 and 4 degrees C. DNA sequencing of gene VIII of the 34 fd isolates revealed five different mutants: these were D5H, M28L, V31L, I37T, and S50T. All 26 M13 isolates were I37T. These mutants exhibited variable sensitivity to chloroform, but all contracted much more slowly than wild-type phage during treatment at 4 degrees C. They all contracted like wild-type phage at 37 degrees C. Site-directed mutagenesis showed that the indicated single mutations carried the chloroform resistance. In structural models of the phage, the D5H locus is on the outside and the S50T locus is on the inside. The M28L and I37T loci are buried in a mostly hydrophobic region in the middle. Although these four mutants are spread out radially, they are localized in the axial direction into a thin disk in the model. The last mutant locus, V31L, is out of this disk, but this locus is proximal to the M28L and I37T loci and also in contact with the surface via a deep hydrophobic hole or depression. These five mutants, their locations, and their variable affects on contraction suggest that chloroform-induced contraction involves a specific mechanism rather than a generalized solvent-induced denaturation and that the critical structural changes occur in a localized level in the phage. These results add weight to suggestions that the sequential contraction of filaments-->I-forms-->S-forms mimic corresponding steps in phage penetration, and, in the reverse order, for phage assembly.


Assuntos
Bacteriófago M13/genética , Bacteriófago M13/ultraestrutura , Inovirus/genética , Inovirus/ultraestrutura , Mutação , Bacteriófago M13/efeitos dos fármacos , Capsídeo/química , Capsídeo/ultraestrutura , Clorofórmio/farmacologia , Resistência Microbiana a Medicamentos/genética , Escherichia coli/virologia , Inovirus/efeitos dos fármacos , Microscopia Eletrônica , Modelos Biológicos , Modelos Moleculares , Fenótipo , Virulência/efeitos dos fármacos
6.
Ground Water ; 43(5): 669-78, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16149962

RESUMO

In Europe, a long history of cooperation over transboundary rivers--most notably the Rhine and Danube rivers--exists. To help foster cooperation and communication vis-à-vis transboundary ground water, the United Nations Economic Commission for Europe (UNECE), as part of its ground water program, conducted a survey on transboundary aquifers in Europe. The survey produced 25 responses from 37 countries and identified 89 transboundary aquifers. Respondents reported on the degree of ground water use within their own boundaries, transboundary aspects (agreements, joint commissions, etc.) of ground water, and transboundary aquifers themselves. The inventory proved useful, but a number of problems were identified: different map scales and symbols, difficulty in identifying transboundary aquifers, inconsistent labeling of aquifers, and data discrepancies. The UNECE ground water program also drafted guidelines for monitoring and assessment of transboundary ground water. These guidelines are not legally binding but have been adopted by 25 countries, deal mainly with monitoring and assessment, and are being implemented through a number of pilot projects. Other organizations-the United Nations Scientific, Educational and Cultural Organization, the Food and Agriculture Organization, the International Association of Hydrogeologists, and the European Union--are all supporting the investigation of transboundary aquifers in an effort to facilitate data sharing and coordinated management of these valuable resources.


Assuntos
Cooperação Internacional , Abastecimento de Água , Conservação dos Recursos Naturais , Monitoramento Ambiental , Europa (Continente) , Agências Internacionais , Inquéritos e Questionários
7.
Syst Rev ; 4: 71, 2015 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-25982565

RESUMO

BACKGROUND: This study aims to determine the prognostic accuracy of term MRI in very preterm born (≤32 weeks) or low-birth-weight (≤1500 g) infants for long-term (>18 months) developmental outcomes. METHODS: We performed a systematic review searching Central, Medline, Embase, and PsycInfo. Two independent reviewers performed study selection, data extraction, and quality assessment. We documented sensitivity and specificity for three different MRI findings (white matter abnormalities (WMA), brain abnormality (BA), and diffuse excessive high signal intensity (DEHSI)), related to developmental outcomes including cerebral palsy (CP), visual and/or hearing problems, motor, neurocognitive, and behavioral function. Using bivariate meta-analysis, we estimated pooled sensitivity and specificity and plotted summary receiver operating characteristic (sROC) curves for different cut-offs of MRI. RESULTS: We included 20 papers published between 2000 and 2013. Quality of included studies varied. Pooled sensitivity and specificity values (95 % confidence interval (CI)) for prediction of CP combining the three different MRI findings (using normal/mild vs. moderate/severe cut-off) were 77 % (53 to 91 %) and 79 % (51 to 93 %), respectively. For prediction of motor function, the values were 72 % (52 to 86 %) and 62 % (29 to 87 %), respectively. Prognostic accuracy for visual and/or hearing problems, neurocognitive, and/or behavioral function was poor. sROC curves of the individual MRI findings showed that presence of WMA provided the best prognostic accuracy whereas DEHSI did not show any potential prognostic accuracy. CONCLUSIONS: This study shows that presence of moderate/severe WMA on MRI around term equivalent age can predict CP and motor function in very preterm or low-birth-weight infants with moderate sensitivity and specificity. Its ability to predict other long-term outcomes such as neurocognitive and behavioral impairments is limited. Also, other white matter related tests as BA and DEHSI demonstrated limited prognostic value. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42013006362.


Assuntos
Encéfalo/patologia , Deficiências do Desenvolvimento/diagnóstico , Recém-Nascido Prematuro , Imageamento por Ressonância Magnética , Feminino , Humanos , Recém-Nascido , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
FEBS Lett ; 292(1-2): 271-4, 1991 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-1959617

RESUMO

Below 15 degrees C, chloroform causes fd phage to contract to I-forms, which are compact structures about 1/3 as long as the original phage. Above 15 degrees C, chloroform causes I-forms to contract to even more compact spheroidal S-forms. Here we show that the coat protein structure in I-forms is the same as the protein structure in the phage and the protein structure in S-forms is the same as the protein structure in bilayers. The conversions from fd----I-forms----S-forms are therefore suggested to mimic steps in fd penetration. The same conversions, in reverse order, are suggested to mimic steps in fd assembly.


Assuntos
Bacteriófagos/fisiologia , Capsídeo/química , Dicroísmo Circular , Conformação Proteica , Análise Espectral Raman
9.
FEBS Lett ; 292(1-2): 275-8, 1991 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-1959618

RESUMO

The fd filamentous phage can be contracted to short rods called I-forms and to spheroidal particles called S-forms. The conversions from fd----I-forms----S-forms were previously suggested to mimic steps in fd penetration. The same conversions, in reverse order, were suggested to mimic steps in fd assembly. The I-forms and S-forms bind the hydrophobic probe, 1-anilino-napthalene-8-sulfonate (ANS); under the same conditions, fd binds this probe very poorly. Rigidly packed side chains in fd and nonrigidly packed side chains in I-forms and S-forms would explain the differences in ANS binding. A compilation of the properties of I-forms and S-forms indicate that: (i) they have compact structures; (ii) they have secondary structures of the same type as native phage; (iii) they have non-native morphologies; and (iv) they may have nonrigid side chain packing. These are the properties of molten globules.


Assuntos
Bacteriófagos/fisiologia , Naftalenossulfonato de Anilina/química , Bacteriófagos/ultraestrutura , Capsídeo/química , Microscopia Eletrônica , Conformação Proteica
10.
J Biomol Struct Dyn ; 12(2): 457-74, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7702780

RESUMO

Hinge-bending in T4 lysozyme has been inferred from single amino acid mutant crystalline allomorphs by Matthews and coworkers. This raises an important question: are the different conformers in the unit cell artifacts of crystal packing forces, or do they represent different solution state structures? The objective of this theoretical study is to determine whether domain motions and hinge-bending could be simulated in T4 lysozyme using molecular dynamics. An analysis of a 400 ps molecular dynamics simulation of the 164 amino acid enzyme T4 lysozyme is presented. Molecular dynamics calculations were computed using the Discover software package (Biosym Technologies). All hydrogen atoms were modeled explicitly with the inclusion of all 152 crystallographic waters at a temperature of 300 K. The native T4 lysozyme molecular dynamics simulation demonstrated hinge-bending in the protein. Relative domain motions between the N-terminal and C-terminal domains were evident. The enzyme hinge bending sites resulted from small changes in backbone atom conformations over several residues rather than rotation about a single bound. Two hinge foci were found in the simulation. One locus comprises residues 8-14 near the C-terminal of the A helix; the other site, residues 77-83 near the C-terminal of the C helix. Comparison of several snapshot structures from the dynamics trajectory clearly illustrates domain motions between the two lysozyme lobes. Time correlated atomic motions in the protein were analyzed using a dynamical cross-correlation map. We found a high degree of correlated atomic motions in each of the domains and, to a lesser extent, anticorrelated motions between the two domains. We also found that the hairpin loop in the N-terminal lobe (residues 19-24) acted as a mobile 'flap' and exhibited highly correlated dynamic motions across the cleft of the active site, especially with residue 142.


Assuntos
Muramidase/química , Estrutura Secundária de Proteína , Bacteriófago T4/enzimologia , Simulação por Computador , Cristalografia por Raios X , Modelos Moleculares , Mutagênese Sítio-Dirigida , Proteínas Recombinantes/química , Software , Termodinâmica
11.
Laryngoscope ; 89(10 Pt 1): 1689-96, 1979 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-228137

RESUMO

Seventeen cases of juvenile laryngeal papillomatosis have been seen and treated with microlaryngoscopy, removal of papillomas, and administering of autogenous vaccine. Holinger's original findings could be confirmed. The operation frequency of 9 patients was significantly reduced, 5 were improved, and 3 unchanged. In no case was an undesirable reaction to the vaccine observed. Electron microscopy showed no virus-like particles in the papilloma but a section of a vulvar wart did show the virus.


Assuntos
Neoplasias Laríngeas/terapia , Papiloma/terapia , Papillomaviridae/imunologia , Vacinas contra Papillomavirus , Vacinas Virais/uso terapêutico , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Neoplasias Laríngeas/imunologia , Laringoscopia , Masculino , Microscopia Eletrônica , Papiloma/imunologia , Papiloma/ultraestrutura
12.
Syst Rev ; 2: 109, 2013 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-24313949

RESUMO

BACKGROUND: Although it is often performed in clinical practice, the diagnostic value of a screening physical examination to detect maltreatment in children without prior suspicion has not been reviewed. This article aims to evaluate the diagnostic value of a complete physical examination as a screening instrument to detect maltreatment in children without prior suspicion. METHODS: We systematically searched the databases of MEDLINE, EMBASE, PsychINFO, CINAHL, and ERIC, using a sensitive search strategy. Studies that i) presented medical findings of a complete physical examination for screening purposes in children 0-18 years, ii) specifically recorded the presence or absence of signs of child maltreatment, and iii) recorded child maltreatment confirmed by a reference standard, were included. Two reviewers independently performed study selection, data extraction, and quality appraisal using the QUADAS-2 tool. RESULTS: The search yielded 4,499 titles, of which three studies met the eligibility criteria. The prevalence of confirmed signs of maltreatment during screening physical examination varied between 0.8% and 13.5%. The designs of the studies were inadequate to assess the diagnostic accuracy of a screening physical examination for child maltreatment. CONCLUSIONS: Because of the lack of informative studies, we could not draw conclusions about the diagnostic value of a screening physical examination in children without prior suspicion of child maltreatment.


Assuntos
Maus-Tratos Infantis/diagnóstico , Exame Físico , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Projetos de Pesquisa
18.
Otolaryngol Pol ; 29(3): 231-5, 1975.
Artigo em Polonês | MEDLINE | ID: mdl-1161286
19.
Br J Cancer ; 98(6): 1059-67, 2008 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-18349818

RESUMO

Erythropoietin receptor (EpoR) has been reported to be overexpressed in tumours and has raised safety concerns regarding the use of erythropoiesis-stimulating agents (ESAs) to treat anaemia in cancer patients. To investigate the potential for EpoR to be overexpressed in tumours, we have evaluated human tumours for amplification of the EPOR locus, levels of EPOR transcripts, and expression of surface EpoR protein. Gene amplification analysis of 1083 solid tumours found that amplification of the EPOR locus was rare with frequencies similar to other non-oncogenes. EPOR transcript levels in tumours and tumour cell lines were low in comparison with bone marrow and were equivalent to, or lower than, levels in normal tissues of tumour origin. Although EpoR mRNA was detected in some tumour lines, no EpoR could be detected on the cell surface using (125)I-Epo binding studies. This may be due to the lack of EpoR protein expression or lack of cell-surface-trafficking factors, such as Jak2. Taken together, we have found no evidence that EpoR is overexpressed in tumours or gets to the surface of tumour cells. This suggests that there is no selective advantage for tumours to overexpress EpoR and questions the functional relevance of EpoR gene transcription in tumours.


Assuntos
Neoplasias/genética , Receptores da Eritropoetina/genética , Linhagem Celular , Amplificação de Genes , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/análise , Receptores da Eritropoetina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica
20.
Proteins ; 18(1): 19-33, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8146120

RESUMO

In this report we examine several solvent models for use in molecular dynamics simulations of protein molecules with the Discover program from Biosym Technologies. Our goal was to find a solvent system which strikes a reasonable balance among theoretical rigor, computational efficiency, and experimental reality. We chose phage T4 lysozyme as our model protein and analyzed 14 simulations using different solvent models. We tested both implicit and explicit solvent models using either a linear distance-dependent dielectric or a constant dielectric. Use of a linear distance-dependent dielectric with implicit solvent significantly diminished atomic fluctuations in the protein and kept the protein close to the starting crystal structure. In systems using a constant dielectric and explicit solvent, atomic fluctuations were much greater and the protein was able to sample a larger portion of conformational space. A series of nonbonded cutoff distances (9.0, 11.5, 15.0, 20.0 A) using both abrupt and smooth truncation of the nonbonded cutoff distances were tested. The method of dual cutoffs was also tested. We found that a minimum nonbonded cutoff distance of 15.0 A was needed in order to properly couple solvent and solute. Distances shorter than 15.0 A resulted in a significant temperature gradient between the solvent and solute. In all trajectories using the proprietary Discover switching function, we found significant denaturation in the protein backbone; we were able to run successful trajectories only in those simulations that used no switching function. We were able to significantly reduce the computational burden by using dual cutoffs and still calculate a quality trajectory. In this method, we found that an outer cutoff distance of 15.0 A and an inner cutoff distance of 11.5 worked well. While a 10 A shell of explicit water yielded the best results, a 6 A shell of water yielded satisfactory results with nearly a 40% reduction in computational cost.


Assuntos
Bacteriófago T4/enzimologia , Modelos Químicos , Muramidase/química , Simulação por Computador , Cristalografia por Raios X , Impedância Elétrica , Ligação de Hidrogênio , Modelos Moleculares , Movimento (Física) , Software , Solventes , Água/química
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