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1.
Public Health ; 221: 190-197, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37480745

RESUMO

OBJECTIVES: Whole-school interventions that promote student commitment to school are a promising modality to reduce health inequalities through school-level change; however, evidence for the effectiveness of these interventions in improving policy-relevant health outcomes, such as substance use and violence, has not been comprehensively synthesised. STUDY DESIGN: This was a systematic review and meta-analysis. METHODS: We searched 20 databases and a range of other sources to identify randomised trials meeting our intervention definition and reporting substance use and violence outcomes. Extracted effect estimates were meta-analysed using robust variance estimation with random effects, separating effects <1 year from baseline and effects at or more than 1 year from baseline. RESULTS: We included 18 evaluations with varying risk of bias. Pooled effects suggested significant impacts on short-term (odds ratio [OR] = 0.85, 95% confidence interval [CI] 0.76, 0.96) and long-term (OR = 0.79, 95% CI 0.65, 0.98) violence perpetration, short-term (OR = 0.84, 95% CI 0.72, 0.98) and long-term (OR = 0.85, 95% CI 0.73, 0.99) violence victimisation, and short-term (OR = 0.83, 95% CI 0.70, 0.97) and long-term (OR = 0.79, 95% CI 0.62, 0.998) substance use outcomes, with effects relatively stable between short-term and long-term analyses. Stratifying substance use meta-analyses by type (e.g. smoking, alcohol) did not impact results. All meta-analyses had substantial heterogeneity. CONCLUSION: Although diverse in content, interventions appear effective with respect to the review outcomes and as a form of universal prevention. Future research should consider contextual contingencies in intervention effectiveness, given considerable policy and practice interest in these interventions and the need to support schools in effective decision-making as to intervention choice.


Assuntos
Instituições Acadêmicas , Transtornos Relacionados ao Uso de Substâncias , Humanos , Violência/prevenção & controle , Estudantes , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle
2.
Int J Tuberc Lung Dis ; 25(5): 358-366, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33977903

RESUMO

BACKGROUND: Barts Health National Health Service Trust (BHNHST) serves a diverse population of 2.5 million people in London, UK. We undertook a health services assessment of factors used to evaluate the risk of severe acute respiratory coronavirus 2 (SARS-CoV-2) infection.METHODS: Patients with confirmed polymerase chain reaction (PCR) test results admitted between 1 March and 1 August 2020 were included, alongwith clinician-diagnosed suspected cases. Prognostic factors from the 4C Mortality score and 4C Deterioration scores were extracted from electronic health records and logistic regression was used to quantify the strength of association with 28-day mortality and clinical deterioration using national death registry linkage.RESULTS: Of 2783 patients, 1621 had a confirmed diagnosis, of whom 61% were male and 54% were from Black and Minority Ethnic groups; 26% died within 28 days of admission. Mortality was strongly associated with older age. The 4C mortality score had good stratification of risk with a calibration slope of 1.14 (95% CI 1.01-1.27). It may have under-estimated mortality risk in those with a high respiratory rate or requiring oxygen.CONCLUSION: Patients in this diverse patient cohort had similar mortality associated with prognostic factors to the 4C score derivation sample, but survival might be poorer in those with respiratory failure.


Assuntos
COVID-19 , Medicina Estatal , Idoso , Feminino , Hospitalização , Humanos , Londres/epidemiologia , Masculino , Fatores de Risco , SARS-CoV-2
3.
Acta Paediatr ; 108(4): 654-661, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30030933

RESUMO

AIM: We determined the safety, feasibility and sustainability of an outpatient model of care for infants exposed to intra-uterine drugs. METHODS: This was a retrospective chart review of 774 drug-exposed infants born between 1998 and 2016 at the Royal Hospital for Women, Sydney, Australia. RESULTS: Most (86%) of the mothers used multiple drugs, including opioids (58%). More than three-quarters (78%) of the infants were born full term at a mean gestation of 38 weeks and hospitalised for a median of seven days. This rose to 14 days if they were medicated for neonatal abstinence syndrome (NAS). Most of the NAS patients (83%) were discharged on medication, namely morphine, and the median duration of NAS treatment was 76 (interquartile range 35-120). Three medication errors occurred: two extra doses of phenobarbitone and one infant weaned off morphine faster than prescribed. No infants were rehospitalised for NAS. Four died from sudden infant death syndrome at 2.2-5.8 months after discharge and one drowned at 15 months. None were medicated at the time of death. CONCLUSION: Outpatient care for drug-exposed infants was sustainable and had low complication rates, even for those with NAS. The optimum duration of follow-up and impact on hospital costs should be examined.


Assuntos
Assistência Ambulatorial , Síndrome de Abstinência Neonatal/terapia , Complicações na Gravidez , Transtornos Relacionados ao Uso de Substâncias , Adulto , Estudos de Viabilidade , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Estudos Retrospectivos , Resultado do Tratamento
4.
Int J Inj Contr Saf Promot ; 24(4): 501-509, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28118777

RESUMO

The objective of this study is to determine the contribution of Chile's 2005 child restraint legislation to the reduction of child passenger fatalities and severe injuries. We analysed motor vehicle injury and fatality data from Chile's National Road Safety Commission of the Ministry of Transport from 2000 to 2012 to determine the effect of Chile's 2005 mandatory child restraint legislation. Using interrupted time-series Poisson regression models, we assessed the effect of the law on two dependent variables: (1) number of child fatalities in car and (2) number of children severely injured. The independent variable was the 2005 enactment of Chile's mandatory child restraint legislation. Coefficients from the interrupted time-series Poisson regression models indicate that Chile's enactment of child restraint legislation in 2005 is significantly associated with a total of 35% reduction in child passenger severely injured but only three years after its enactment, and significant associations between this policy and child fatalities were less evident.


Assuntos
Acidentes de Trânsito/mortalidade , Acidentes de Trânsito/estatística & dados numéricos , Condução de Veículo/legislação & jurisprudência , Sistemas de Proteção para Crianças , Ferimentos e Lesões/epidemiologia , Automóveis/estatística & dados numéricos , Criança , Pré-Escolar , Chile/epidemiologia , Humanos , Lactente , Recém-Nascido , Análise de Séries Temporais Interrompida , Distribuição de Poisson , Índices de Gravidade do Trauma
5.
J Perinatol ; 34(6): 417-24, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24457255

RESUMO

To review and summarise the literature reporting on cannabis use within western communities with specific reference to patterns of use, the pharmacology of its major psychoactive compounds, including placental and fetal transfer, and the impact of maternal cannabis use on pregnancy, the newborn infant and the developing child. Review of published articles, governmental guidelines and data and book chapters. Although cannabis is one of the most widely used illegal drugs, there is limited data about the prevalence of cannabis use in pregnant women, and it is likely that reported rates of exposure are significantly underestimated. With much of the available literature focusing on the impact of other illicit drugs such as opioids and stimulants, the effects of cannabis use in pregnancy on the developing fetus remain uncertain. Current evidence indicates that cannabis use both during pregnancy and lactation, may adversely affect neurodevelopment, especially during periods of critical brain growth both in the developing fetal brain and during adolescent maturation, with impacts on neuropsychiatric, behavioural and executive functioning. These reported effects may influence future adult productivity and lifetime outcomes. Despite the widespread use of cannabis by young women, there is limited information available about the impact perinatal cannabis use on the developing fetus and child, particularly the effects of cannabis use while breast feeding. Women who are using cannabis while pregnant and breast feeding should be advised of what is known about the potential adverse effects on fetal growth and development and encouraged to either stop using or decrease their use. Long-term follow-up of exposed children is crucial as neurocognitive and behavioural problems may benefit from early intervention aimed to reduce future problems such as delinquency, depression and substance use.


Assuntos
Cannabis/efeitos adversos , Desenvolvimento Fetal/efeitos dos fármacos , Abuso de Maconha/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Adulto , Aleitamento Materno , Criança , Feminino , Feto , Humanos , Lactente , Recém-Nascido , Abuso de Maconha/complicações , Gravidez , Fatores de Risco
6.
Clin Nutr ; 32(2): 162-71, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23159212

RESUMO

Intestinal failure (IF) is a well identified clinical condition, which is characterised by the reduction of functional gut capacity below the minimum needed for adequate digestion and absorption of nutrients for normal growth in children. Short bowel syndrome (SBS) is the leading cause of IF in neonates, infants and young children usually as a result of extensive intestinal resection during the neonatal period. Simultaneously maintaining optimal nutritional status and achieving intestinal adaptation is a clinical challenge in short bowel patients. Both growth and development of the child as well as gut adaptation should be considered synergistically as primary outcome parameters. Enteral nutrition (EN) can be introduced orally and/or by tube feeding (TF). Several controversies over nutritional treatment of children with SBS related intestinal failure remain. As reported from different centres around the world, most practices are more "experienced based" rather than "evidence based". This is partly due to the small number of patients with this condition. This review (based on a consensus) discusses the physiological principles and nutritional management, including the type of diet and route of delivery. Perspectives in optimizing intestinal adaptation and reducing the consequences of small intestinal bacterial overgrowth are also discussed.


Assuntos
Nutrição Enteral , Intestino Delgado/fisiopatologia , Síndrome do Intestino Curto/dietoterapia , Síndrome do Intestino Curto/fisiopatologia , Adaptação Fisiológica , Pré-Escolar , Dieta , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Fibras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Ácidos Graxos Insaturados/administração & dosagem , Humanos , Lactente , Recém-Nascido , Estado Nutricional , Probióticos/administração & dosagem
7.
J Perinatol ; 32(10): 737-47, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22652562

RESUMO

The objective of this study is to review and summarize available evidence regarding the impact of amphetamines on pregnancy, the newborn infant and the child. Amphetamines are neurostimulants and neurotoxins that are some of the most widely abused illicit drugs in the world. Users are at high risk of psychiatric co-morbidities, and evidence suggests that perinatal amphetamine exposure is associated with poor pregnancy outcomes, but data is confounded by other adverse factors associated with drug-dependency. Data sources are Government data, published articles, conference abstracts and book chapters. The global incidence of perinatal amphetamine exposure is most likely severely underestimated but acknowledged to be increasing rapidly, whereas exposure to other drugs, for example, heroin, is decreasing. Mothers known to be using amphetamines are at high risk of psychiatric co-morbidity and poorer obstetric outcomes, but their infants may escape detection, because the signs of withdrawal are usually less pronounced than opiate-exposed infants. There is little evidence of amphetamine-induced neurotoxicity and long-term neurodevelopmental impact, as data is scarce and difficult to extricate from the influence of other factors associated with children living in households where one or more parent uses drugs in terms of poverty and neglect. Perinatal amphetamine-exposure is an increasing worldwide concern, but robust research, especially for childhood outcomes, remains scarce. We suggest that exposed children may be at risk of ongoing developmental and behavioral impediment, and recommend that efforts be made to improve early detection of perinatal exposure and to increase provision of early-intervention services for affected children and their families.


Assuntos
Transtornos Relacionados ao Uso de Anfetaminas/epidemiologia , Anfetaminas/efeitos adversos , Troca Materno-Fetal , Complicações na Gravidez/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Transtornos Relacionados ao Uso de Anfetaminas/tratamento farmacológico , Anfetaminas/administração & dosagem , Criança , Feminino , Humanos , Recém-Nascido , Gravidez , Complicações na Gravidez/tratamento farmacológico , Resultado da Gravidez , Fatores de Risco
8.
J S Afr Vet Assoc ; 77(1): 24-7, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16700472

RESUMO

Placental microvesicles were prepared from ovine placentae and immunoglobulins eluted with 0.5 M glycine buffer pH 2.5. The ability of eluate immunoglobulins to re-associate with isologous (self) and third party acidified microvesicles was tested by ELISA. Ovine placental immunoglobulins re-associated with isologous and third party acidified microvesicles suggesting that at least 2 types of antigenic epitopes I and II maybe expressed on the ovine placentae. Type I antigens may be present on placentae of all ovines while type II epitopes may be paternally derived, hence unique to each pregnancy. Analysis by SDS PAGE revealed the heavy and light chains of IgG at 57 and 27 kDa, respectively, together giving a relative molecular weight of 158 kDa. Results suggest that immunoglobulins produced to placental microvesicle antigens may be directed to some but not all antigenic epitopes expressed on the trophoblast, possibly defining a mechanism by which the foetus evades maternal immunological rejection.


Assuntos
Ácidos/farmacologia , Antígenos/imunologia , Epitopos/imunologia , Imunoglobulinas/imunologia , Placenta/imunologia , Animais , Eletroforese em Gel de Poliacrilamida/veterinária , Feminino , Imunoglobulinas/isolamento & purificação , Técnicas In Vitro , Peso Molecular , Gravidez , Ovinos
9.
East Afr Med J ; 82(6): 290-3, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16175779

RESUMO

OBJECTIVE: To study re-association pattern of human placental eluate immunoglobulins with acid treated isologous and third party trophoblast derived placental microvesicles. DESIGN: Laboratory based experimentation. SETTING: Biological Sciences Department and Discipline for Reproductive Medicine University of Newcastle, Australia and the Department of Biochemistry, University of Nairobi, Kenya. RESULTS: Placental eluate immunoglobulins re-associated with isologous and third party acidified microvesicles in three distinct patterns. I: eluate immunoglobulins re-associated more strongly with isologous and third party acid treated placental microvesicles, II: eluate immunoglobulins re-associated strongly with isologous but weakly with third party acid treated placental microvesicles, III: eluate immunoglobulins did not show preferential re-association with isologous and third party acid treated placental microvesicles. CONCLUSION: Two types of antigenic epitopes I and II may be expressed on the human placentae. Type I antigens may be present on all human placentae while type II epitopes may be paternally derived hence unique to each pregnancy. Also, immunoglobulins produced to placental microvesicle antigens may be directed to some but not all antigenic epitopes expressed on the human placental trophoblast.


Assuntos
Ácidos/farmacologia , Antígenos/imunologia , Epitopos/imunologia , Imunoglobulinas/imunologia , Placenta/imunologia , Gravidez/imunologia , Trofoblastos/imunologia , Antígenos/isolamento & purificação , Sangue , Feminino , Reabsorção do Feto , Humanos , Imunoglobulinas/isolamento & purificação , Técnicas In Vitro , Troca Materno-Fetal/imunologia
10.
J Laparoendosc Adv Surg Tech A ; 15(1): 48-50, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15772476

RESUMO

Two female patients underwent an uneventful laparoscopic chloecystectomy (LC) for cholelithiasis. Their past medical history was insignificant. The first patient had diclofenac sodium for her postoperative pain relief. Both patients returned in the early postoperative period with pain in the right hypochondrium. Laboratory investigations revealed elevated leucocytes, C reactive protein (CRP), and deranged liver function tests. A computed tomography (CT) scan showed subcapsular haematoma of liver. CT-guided aspiration of hematoma was done in one case. Both patients improved over a period of time and a follow-up radiological scan showed resolving hematoma. The presentation, diagnostic evaluation, treatment, and possible causes are discussed.


Assuntos
Colecistectomia/efeitos adversos , Colecistectomia/métodos , Hematoma/etiologia , Laparoscopia/efeitos adversos , Hepatopatias/etiologia , Idoso , Feminino , Hematoma/diagnóstico por imagem , Hematoma/terapia , Humanos , Hepatopatias/diagnóstico por imagem , Hepatopatias/terapia , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
11.
East Afr Med J ; 82(9): 468-72, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16619721

RESUMO

OBJECTIVE: To elute placental bound immunoglobulin G (IgG) in situ. DESIGN: Laboratory based experimentation. SETTING: Biological Sciences Department, The University of Newcastle Australia and the Department of Biochemistry, University of Nairobi, Kenya. SUBJECTS: Twelve pregnant ewes 10 to 15 days before the onset of natural parturition. RESULTS: Placental eluates were rich in IgG, and IgG2. The relative molecular weight of placental IgG was estimated at 158kDa by gel filtration chromatography. Analysis of eluate by SDS PAGE revealed the heavy and light chains of IgG at 57 and 27kDa respectively together giving a relative molecular weight of 168kDa. CONCLUSION: Placental bound IgG may be crucial in immunology of pregnancy and together with the cognate antigen thereof may be useful as models for the study of maternal-fetal interaction in human pregnancy and in the development of experimental immunotherapy to immunologically compromised pregnancies in humans and livestock.


Assuntos
Ácidos/isolamento & purificação , Cateterismo , Imunoglobulina G/isolamento & purificação , Placenta/imunologia , Ácidos/metabolismo , Animais , Antígenos/química , Antígenos/isolamento & purificação , Antígenos/metabolismo , Cromatografia em Gel , Feminino , Imunoglobulina G/metabolismo , Troca Materno-Fetal/imunologia , Peso Molecular , Perfusão , Placenta/irrigação sanguínea , Gravidez , Ligação Proteica , Carneiro Doméstico
12.
Water Sci Technol ; 49(4): 141-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15077962

RESUMO

Methyl tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) were oxidized in the gas phase by photocatalytic oxidation (PCO). Transient PCO was carried out at room temperature on TiO2 (Degussa P25), 0.2% Pt-TiO2, and 2% Pt-TiO2 catalysts. Surface-adsorbed reaction by-products were characterized by temperature-programmed desorption (TPD) and oxidation (TPO). Continuous flow PCO was also carried out at 373 K on TiO2. Acetone, H2O, and CO2 were the gas-phase products for PCO of TBA and MTBE, and formic acid was adsorbed on the TiO2 surface. Temperature-programmed desorption of TBA and MTBE formed 2-methyl-1-propene, water (TBA), and methanol (MTBE). During continuous-flow PCO, acetone desorbed in molar amounts equal to the amount of decomposed TBA and MTBE. The Pt/TiO2 catalysts had higher rates of complete oxidation during PCO and TPO. Injection of water during transient PCO increased the rates of oxidation of adsorbed TBA, formic acid, and acetone. Photocatalytic oxidation of TBA proceeded faster in humid air than dry air, but MTBE oxidation was less sensitive to humidity. The TiO2 catalyst was stable for MTBE, TBA, and acetone PCO at 373 K. The PCO at low conversions followed the Langmuir-Hinshelwood model.


Assuntos
Carcinógenos/química , Carcinógenos/isolamento & purificação , Éteres Metílicos/química , Éteres Metílicos/isolamento & purificação , Solventes/química , Solventes/isolamento & purificação , Purificação da Água/métodos , terc-Butil Álcool/química , terc-Butil Álcool/isolamento & purificação , Catálise , Gases , Umidade , Oxirredução , Fotoquímica , Temperatura
13.
Environ Sci Technol ; 35(14): 2988-94, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11478253

RESUMO

A transparent, thin-film TiO2 layer prepared by sol-gel deposition is shown to be more active for photocatalytic oxidation (PCO) of acetaldehyde, acetic acid, and toluene than Degussa P25 thin films. The sol-gel TiO2 adsorbs 30-70% less organic, but the PCO activity per adsorbed molecule is 3.5-8.5 times higher on the sol-gel TiO2 than on Degussa P25. In addition, less-reactive intermediates do not appear to form as readily on the sol-gel catalyst as they do on Degussa P25, and thus the sol-gel catalyst deactivates slower during toluene PCO. Rates were measured in transient experiments for a monolayer of adsorbed organic, and transient experiments are shown to be an effective way to measure rates, selectivities, surface coverages, and formation of less-reactive intermediates in the same set of experiments.


Assuntos
Poluição do Ar/prevenção & controle , Fármacos Fotossensibilizantes/química , Titânio/química , Catálise , Gases , Géis , Compostos Orgânicos , Oxirredução , Fotólise
14.
Environ Sci Technol ; 35(6): 1252-8, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11347941

RESUMO

Transient reaction of adsorbed monolayers of acetic acid was used to characterize the photocatalytic properties of titanium silicalite zeolites (TS-1). The TS-1 zeolites having Si/Ti ratios of 5, 12.5, and 50 are effective catalysts at room temperature for both photocatalytic oxidation (PCO) and decomposition (PCD) of acetic acid. The rates of PCO are higher than the rates of PCD for each catalyst. Acetic acid oxidized photocatalytically in 0.2% O2 to form gas-phase CO2 and CH4 and adsorbed H2O on the TS-1 catalysts, whereas no CH4 formed on Degussa P25 TiO2. Isotope labeling showed that, on both TiO2 and TS-1 catalysts, the alpha-carbon formed CO2 whereas the beta-carbon formed CH4 and CO2. The rates of oxidation of the two carbons have different dependencies on UV intensity. The catalysts with higher Si/Ti ratios adsorbed significantly more acetic acid, and the PCO rates per gram of titanium are highest on the TS-1 catalyst with the lowest Ti content, apparently because a larger fraction of the Ti atoms are surface atoms on this catalyst. During PCD in an inert atmosphere, CO2, CH4, and C2H6 formed on TiO2 and on the catalyst with a Si/Ti ratio of 5, but C2H6 was not detected on the other catalysts. The CO2/CH4 selectivity during PCD increased with increasing Si/Ti ratio. The first step in PCO and PCD on TS-1 catalysts appears to be similar and involves formation of a CH3 radical.


Assuntos
Ácido Acético/química , Poluentes Atmosféricos/química , Poluição do Ar/prevenção & controle , Silicatos/química , Titânio/química , Catálise , Oxirredução , Fotoquímica , Difração de Raios X
15.
J Nutr Biochem ; 12(5): 258-265, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11382543

RESUMO

Dietary supplementation with marine fish oils rich in n-3 fatty acids reduces circulating thromboxane A(2) (TxA(2)). However, the effects on thomboxane A(2) receptor mediated vascular reactivity are uncertain. The aim of this study was to test the hypothesis that dietary modification of TxA(2) levels alters vascular responsiveness to TxA(2) analogues. Juvenile female white pigs were fed a diet enriched in either 5% (w/w) fish oil or beef tallow for 6 weeks. Serum and myocardial tissue levels of eicosapentaenoic and docosahexaenoic acid reached a plateau during this period. Vascular responses were measured in isolated coronary arterial rings with intact endothelium by isometric tension measurement. Arteries from pigs fed fish oil produced a greater maximum vasoconstrictor tension to the TxA(2) analogue U46619 than did rings from pigs fed beef tallow (120 +/- 6% compared to 92 +/- 8%, values represented as a percentage relative to the maximum vasoconstrictor effect obtained to KCl, regression analysis, analysis of variance, P

16.
Afr J Health Sci ; 8(1-2): 2-16, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-17650042

RESUMO

The unexpected failure of the mother to immunologically reject the foetus is partly thought to result from immunological properties of the placenta. The placental trophoblast produces immunosuppressive factors including progesterone and blocking antibodies which together down-regulate maternal immune responses to the foetoplacental unit. This article reviews the post implantation immunology of pregnancy emphasizing the roles of placenta, blocking factors and natural killer (NK) cells.

17.
Afr J Health Sci ; 8(1-2): 47-54, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-17650047

RESUMO

To determine the effect of ovine and human placental IgG on human Natural Killer (NK) cell cytotoxicity in vitro placental IgG was eluted at acidic pH and purified by ion exchange and subsequently by affinity chromatography on protein G and protein A sepharose columns. These antibodies were analysed for presense of IgG by immuno-electrophoresis and relative purity determined by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS PAGE). The effect of these antibodies on human NK cell cytotoxicity was investigated by slChromium Release Assay using human K562 cells as targets and human peripheral blood lymphocytes as effector cells. Both ovine and human placental IgG inhibited human NK cell cytotoxicity in a dose dependent manner. Placental IgG may down-regulate the cytotoxic effects of NK cells in vivo by competitively excluding the binding of NK cells to their respective targets on the trophoblast. Alternatively, these antibodies may themselves be toxic to NK cells. Either way, the presence of these antibodies on the placental trophoblast may prevent the binding of NK cells and subsequent immunological rejection of the fetal allograft. Also, ovine placental IgG may be functionally similar to its human counterpart and may therefore be suitable as a model for the study of maternal fetal interaction during pregnancy in humans.

20.
Arch Gynecol Obstet ; 264(1): 3-12, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10985611

RESUMO

Post implantation pregnancy losses are psychologically and economically stressful to the childbearing population. The etiology in the vast majority of cases is unknown but is partly thought to result from a break-down of the maternal tolerance to the fetoplacental unit. Immunologically based therapy remains controversial but no alternative therapy is available at the moment. This article reviews the conceived immunological basis of recurrent pregnancy losses, discussing the controversies arising, and recommending the use of intravenous immunoglobulin, IVIg, in well controlled experiments for further clinical trials.


Assuntos
Aborto Habitual/terapia , Imunoterapia , Feminino , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Gravidez
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