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1.
Crit Rev Food Sci Nutr ; 56(3): 350-63, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25365524

RESUMO

A systematic review and meta-analysis of available randomized controlled trials (RCTs) was conducted to evaluate the effect of zinc (Zn) intake on growth in infants. Out of 5500 studies identified through electronic searches and reference lists, 19 RCTs were selected after applying the exclusion/inclusion criteria. The influence of Zn intake on growth was considered in the overall meta-analysis. Other variables were also taken into account as possible effect modifiers: doses of Zn intake, intervention duration, nutritional status, and risk of bias. From each select growth study, final measures of weight, length, mid upper arm circumference (MUAC), head circumference, weight for age z-score (WAZ), length for age z-score (LAZ), and weight for length z-score (WLZ) were assessed. Pooled ß and 95% confidence interval (CI) were calculated. Additionally, we carried out a sensitivity analysis. Zn intake was not associated with weight, length, MUAC, head circumference, and LAZ in the pooled analyses. However, Zn intake had a positive and statistically effect on WAZ (ß = 0.06; 95%CI 0.02 to 0.10) and WLZ (ß = 0.05; 95%CI 0.01 to 0.08). The dose-response relationship between Zn intake and these parameters indicated that a doubling of Zn intake increased WAZ and WLZ by approximately 4%. Substantial heterogeneity was present only in length analyses (I(2) = 45%; p = 0.03). Zn intake was positively associated with length values at short time (four to 20 weeks) (ß = 0.01; CI 95% 0 to 0.02) and at medium doses of Zn (4.1 to 8 mg/day) (ß = 0.003; CI 95% 0 to 0.01). Nevertheless, the effect magnitude was small. Our results indicate that Zn intake increases growth parameters of infants. Nonetheless, interpretation of these results should be carefully considered.


Assuntos
Desenvolvimento Infantil/efeitos dos fármacos , Zinco/farmacologia , Dieta , Humanos , Lactente , Necessidades Nutricionais , Zinco/administração & dosagem
2.
Anaesthesia ; 72(3): 406-407, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28176322
3.
J Obstet Gynaecol ; 30(7): 679-86, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20925609

RESUMO

We studied neonatal outcomes of infants of obese mothers in a cohort of 6,125 deliveries, using logistic multivariate analysis to remove the role of potential confounding variables. Although, as in previous reports, the crude unadjusted prevalence of several adverse neonatal outcomes was higher in these infants, the multivariable analysis revealed that only two outcomes remained significantly associated with maternal overweight and obesity: neonatal macrosomia (adjusted odds ratios aOR 1.4, p < 0.001) and meconium aspiration syndrome (aOR 1.6, p = 0.05), indicating that the unadjusted association with the other outcomes was caused by confounding factors. Nonetheless, as macrosomia is associated with increased health risks both to the mothers and their infants, and maternal obesity with considerable maternal morbidity during pregnancy, these results should not lead to complacency, but instead encourage better prevention of obesity in general and during pregnancy in particular.


Assuntos
Doenças do Recém-Nascido/epidemiologia , Sobrepeso/epidemiologia , Complicações na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Adolescente , Adulto , Feminino , Macrossomia Fetal/epidemiologia , Humanos , Recém-Nascido , Modelos Logísticos , Síndrome de Aspiração de Mecônio/epidemiologia , Pessoa de Meia-Idade , Morbidade , Análise Multivariada , Gravidez , Prevalência , Prognóstico , Adulto Jovem
4.
J Cell Biol ; 61(1): 45-55, 1974 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-4819306

RESUMO

Lymphocyte cultures from all normal human adults are stimulated by zinc ions to increase DNA and RNA synthesis and undergo blast transformation. Optimal stimulation occurs at 0.1 mM Zn(++). Examination of the effects of other divalent cations reveals that 0.01 mM Hg(++) also stimulates lymphocyte DNA synthesis. Ca(++) and Mg(++) do not affect DNA synthesis in this culture system, while Mn(++), Co(++), Cd(++), Cu(++), and Ni(++) at concentrations of 10(-7)-10(-3) M are inhibitory. DNA and RNA synthesis and blast transformation begin to increase after cultures are incubated for 2-3 days with Zn(++) and these processes reach a maximum rate after 6 days. The increase in Zn(++)-stimulated lymphocyte DNA synthesis is prevented by rendering cells incapable of DNA-dependent RNA synthesis with actinomycin D or by blocking protein synthesis with cycloheximide or puromycin. Zn(++)-stimulated DNA synthesis is also partially inhibited by 5'-AMP and chloramphenicol. Zn(++) must be present for the entire 6-day culture period to produce maximum stimulation of DNA synthesis. In contrast to its ability to independently stimulate DNA synthesis, 0.1 mM Zn(++) inhibits DNA synthesis in phytohemagglutinin-stimulated lymphocytes and L1210 lymphoblasts.


Assuntos
Ativação Linfocitária/efeitos dos fármacos , Zinco/farmacologia , Monofosfato de Adenosina/farmacologia , Cádmio/farmacologia , Células Cultivadas , Cloranfenicol/farmacologia , Cobalto/farmacologia , Cobre/farmacologia , Cicloeximida/farmacologia , DNA/biossíntese , Dactinomicina/farmacologia , Depressão Química , Humanos , Cinética , Lectinas/farmacologia , Linfócitos/metabolismo , Manganês/farmacologia , Níquel/farmacologia , Puromicina/farmacologia , RNA/biossíntese , Estimulação Química , Timidina/metabolismo , Trítio , Uridina/metabolismo , Zinco/antagonistas & inibidores
6.
J Obstet Gynaecol ; 29(7): 609-13, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19757264

RESUMO

Diabetic pregnancies may result in fetal macrosomia when glycaemia is poorly controlled, and when associated with diabetic vasculopathy, with small for gestational age (SGA) neonates. Both groups of infants have high neonatal morbidity. As fetal growth depends on maternal genetic influences, ethnic group or parity, relying exclusively on population-based growth charts may wrongly categorise the growth pattern of these infants. We compared neonatal morbidity and mortality of a cohort of 214 infants of diabetic mothers (IDM), identified either by population standards or by customised birth weight percentiles (adjusted for maternal height, booking weight, parity, ethnic origin, gestational age at delivery and sex). A total of 68 (31.8%) were diagnosed with macrosomia, 11 (16%) of whom were identified by the customised growth method alone, and 16 were diagnosed as SGA (7.5%), of whom the majority (13 or 81.2%) were identified by the customised growth method alone. None had increased mortality and morbidity.


Assuntos
Diabetes Gestacional/fisiopatologia , Desenvolvimento Fetal , Macrossomia Fetal/diagnóstico , Gráficos de Crescimento , Recém-Nascido Pequeno para a Idade Gestacional , Gravidez em Diabéticas/fisiopatologia , Adulto , Estudos de Coortes , Feminino , Macrossomia Fetal/mortalidade , Humanos , Recém-Nascido , Gravidez
7.
J Clin Invest ; 51(12): 3225-34, 1972 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-4640956

RESUMO

We have identified two populations of human lymphocytes differing in responsiveness to the plant mitogen concanavalin A (Con-A). When peripheral blood lymphocytes are passed through a nylon column a population of lymphocytes highly responsive to Con-A adheres to the fibers while a second population of cells relatively unresponsive to Con-A emerges from the column. The untreated peripheral blood lymphocytes are termed "unfiltered" cells while the lymphocytes which pass through the column are termed "filtered" cells. Under standard assay conditions the Con-A-stimulated DNA synthesis is 6.5-fold greater, and the percentage blast formation is four-to fivefold greater in the unfiltered than in the filtered population. Mixing unfiltered with filtered cells fails to induce responsiveness in the latter indicating that a "helper" cell is not involved. The failure of filtered cells to respond to Con-A is specific for that mitogen since both populations respond nearly equally to erythroagglutinating phytohemagglutinin (E-PHA) and the poke weed mitogen (PWM). Binding studies with Con-A-(131)I demonstrate that the unfiltered population possesses approximately three times as many Con-A receptor sites per cell as the filtered cells, although both cell populations bind the mitogen with the same affinity (apparent association constant [K] of 1.67 x 10(6)m(-1)). The relationship between Con-A binding and lymphocyte activation was determined by measuring the effect on DNA synthesis of incubating the two lymphocyte populations with increasing amounts of Con-A. The concentration of Con-A required for half-maximal stimulation of DNA synthesis was 5-14 times greater for the filtered cells. However in the presence of very high Con-A concentrations the filtered cells achieved a maximal rate of DNA synthesis approaching that of the unfiltered population. These data implicate the decreased number of Con-A receptor sites on the filtered cells in their failure to respond to low concentrations of Con-A. A crucial event in the activation of lymphocytes by plant mitogens may be the binding of a critical number of the mitogen molecules to the cell surface.


Assuntos
Lectinas/farmacologia , Linfócitos/imunologia , Sítios de Ligação de Anticorpos , Fracionamento Celular , Membrana Celular/imunologia , Concanavalina A/administração & dosagem , Concanavalina A/metabolismo , Concanavalina A/farmacologia , DNA/biossíntese , Humanos , Isótopos de Iodo , Leucemia Linfoide/imunologia , Ativação Linfocitária , Linfócitos/metabolismo , Timidina/metabolismo , Trítio
8.
J Clin Invest ; 50(4): 818-26, 1971 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-4100684

RESUMO

The effect of phytohemagglutinin (PHA) on the ability of human lymphocytes to transport the nonutilizable amino acid, alpha-aminoisobutyric acid (AIB) has been studied. PHA binds rapidly to plasma membrane receptor sites with half maximal binding requiring approximately 7.5 min. During the first 30 min after PHA addition to lymphocytes no change was detected in AIB transport, but then a linear increase in the initial rate of AIB transport occurred over the next 9 hr. Subsequently, the rate of AIB transport stabilized at a level 6-7 times greater than that found in control lymphocytes. The change in membrane function developed even when de novo protein synthesis was inhibited by 85-90% with puromycin or cycloheximide. However, the PHA effect did not occur when the lymphocytes were maintained at 4 degrees C. Studies of the kinetics of AIB uptake by control and PHA-treated lymphocytes demonstrated that PHA increases the V(max) of AIB uptake by 6-7-fold (0.7 mmumole AIB per 10(6) lymphocytes/15 min versus 0.1 mmumole per 10(6) lymphocytes/15 min) without affecting the Km (Michaelis constant) of the transport system (2mM in both cases).When fetuin was added to lymphocyte cultures to remove bound PHA, the PHA-induced increase in the rate of AIB uptake was arrested at the rate achieved during the time of prior incubation with PHA. This level of AIB transport persisted for at least 3 hr after 80% of the PHA was removed from the cell membrane. These data demonstrate that PHA rapidly induces a change in a lymphocyte cell membrane transport function, and that the continued presence of PHA on the cell membrane is required for the full stimulatory effect to be reached. The data do not distinguish between a direct action of PHA upon the lymphocyte membrane or the possibility that PHA slowly enters into the cell where it then exerts its effect.


Assuntos
Ácidos Aminoisobutíricos/metabolismo , Lectinas/farmacologia , Linfócitos/metabolismo , alfa-Globulinas/farmacologia , Transporte Biológico , Isótopos de Carbono , Técnicas de Cultura , Cicloeximida/farmacologia , DNA/biossíntese , Difusão , Humanos , Cinética , Puromicina/farmacologia , Estimulação Química , Timidina/metabolismo
9.
Mol Cell Biol ; 12(7): 3070-7, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1620116

RESUMO

We describe here a novel member of the bZIP family of DNA-binding proteins, designated E4BP4, that displays an unusual DNA-binding specificity which overlaps that of the activating transcription factor family of factors. When expressed in a transient transfection assay with a suitable reporter plasmid, E4BP4 strongly repressed transcription in a DNA-binding-site-dependent manner. Examination of a series of deletion mutants revealed that sequences responsible for the repressing potential of E4BP4 lie within the carboxyl-terminal region of the protein. No similarity was found between this region and the repressing domains of other known eukaryotic transcriptional repressors.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Plantas/genética , Proteínas Repressoras/genética , Fatores de Transcrição , Sequência de Aminoácidos , Animais , Sequência de Bases , Fatores de Transcrição de Zíper de Leucina Básica , Sítios de Ligação , Análise Mutacional de DNA , Fatores de Ligação G-Box , Dados de Sequência Molecular , Família Multigênica/genética , Placenta , Conformação Proteica , Homologia de Sequência do Ácido Nucleico , Transcrição Gênica , Transfecção
10.
J Pregnancy ; 2017: 8783294, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28210508

RESUMO

The last fifteen years have seen a dramatic increase in both the childbearing age and diversity of women migrating to Canada. The resulting health impact underscores the need to explore access to health services and the related maternal health outcome. This article reports on the results of a scoping review focused on migrant maternal health within the context of accessible and effective health services during pregnancy and following delivery. One hundred and twenty-six articles published between 2000 and 2016 that met our inclusion criteria and related to this group of migrant women, with pregnancy/motherhood status, who were living in Canada, were identified. This review points at complex health outcomes among immigrant and refugee women that occur within the compelling gaps in our knowledge of maternal health during all phases of maternity. Throughout the prenatal, intrapartum, and postnatal periods of maternity, barriers to accessing healthcare services were found to disadvantage immigrant and refugee women putting them at risk for challenging maternal health outcomes. Interactions between the uptake of health information and factors related to the process of immigrant settlement were identified as major barriers. Availability of appropriate services in a country that provides universal healthcare is discussed.


Assuntos
Emigrantes e Imigrantes , Acessibilidade aos Serviços de Saúde , Serviços de Saúde Materna/estatística & dados numéricos , Refugiados , Canadá , Feminino , Humanos , Parto , Gravidez , Fatores de Risco
11.
Infant Behav Dev ; 47: 62-71, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28347907

RESUMO

AIMS: To explore the utility of first-person viewpoint cameras at home, for recording mother and infant behaviour, and for reducing problems associated with participant reactivity, which represent a fundamental bias in observational research. METHODS: We compared footage recording the same play interactions from a traditional third-person point of view (3rd PC) and using cameras worn on headbands (first-person cameras [1st PCs]) to record first-person points of view of mother and infant simultaneously. In addition, we left the dyads alone with the 1st PCs for a number of days to record natural mother-child behaviour at home. Fifteen mothers with infants (3-12 months of age) provided a total of 14h of footage at home alone with the 1st PCs. RESULTS: Codings of maternal behaviour from footage of the same scenario captured from 1st PCs and 3rd PCs showed high concordance (kappa >0.8). Footage captured by the 1st PCs also showed strong inter-rater reliability (kappa=0.9). Data from 1st PCs during sessions recorded alone at home captured more 'negative' maternal behaviours per min than observations using 1st PCs whilst a researcher was present (mean difference=0.90 (95% CI 0.5-1.2, p<0.001 representing 1.5 SDs). CONCLUSION: 1st PCs offer a number of practical advantages and can reliably record maternal and infant behaviour. This approach can also record a higher frequency of less socially desirable maternal behaviours. It is unclear whether this difference is due to lack of need of the presence of researcher or the increased duration of recordings. This finding is potentially important for research questions aiming to capture more ecologically valid behaviours and reduce demand characteristics.


Assuntos
Comportamento do Lactente , Comportamento Materno , Relações Mãe-Filho , Adulto , Feminino , Humanos , Lactente , Masculino , Mães , Reprodutibilidade dos Testes , Gravação em Vídeo
12.
Endocrinology ; 147(4): 1608-20, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16396991

RESUMO

The FecB (Booroola) mutation, which leads to increased ovulation rates and multiple births in sheep, is now known to occur in the signaling domain of the bone morphogenic protein (BMP)-1B receptor. We examined the effect of the mutation on the responsiveness of granulosa (GC) and theca cells (TC) to BMPs and other local regulators using tissue from animals with (Fec(B/B)) and without (Fec(+/+)) the FecB mutation. Experiments examined the effect of BMP-2, -4, and -6 (0.005-50 ng/ml), and their interaction with IGF-I (0.1-10 ng/ml LR3 analog) and gonadotropins, on the proliferation and differentiation of GCs and TCs isolated from small (<2 mm) antral follicles and maintained in serum-free culture for up to 8 d. Dose-finding studies using ovaries from wild-type sheep obtained from the abbattoir showed no difference among the different BMPs in stimulating (P < 0.001) estradiol (E2) production by GCs cultured with FSH (10 ng/ml), but there was a clear interaction (P < 0.001) with IGF-I. BMPs had no effect on GC proliferation or the sensitivity of GCs to FSH. In contrast, higher doses of BMPs (5-50 ng/ml) inhibited LH-stimulated androstenedione production by TCs, whereas lower doses (0.005-0.05 ng/ml) stimulated TC proliferation (P < 0.01). Regardless of dose of IGF-I, at the end of culture (96-192 h) hormone production by GCs (E2, inhibin A) and TCs (androstenedione) was 4- to 5-fold greater (P < 0.001) by cells from Fec(B/B), compared with Fec(+/+) ewes exposed to the same dose of gonadotropin. In the presence of low concentrations of IGF-I (0.1 ng/ml), the maximum increase in the production of E2 and inhibin A by GCs from FF ewes in response to BMPs was observed at doses that were 3- to 10-fold lower (3-10 ng/ml) than ++ (30 ng/ml; P < 0.001). Low doses of BMPs stimulated proliferation of TCs from ++ (P < 0.01) but not FF ewes. Immunohistochemistry confirmed BMP-6 protein expression in the oocyte, granulosa, and thecal layers of antral follicles from both genotypes. These results confirm a major role for BMPs in controlling ovarian somatic cell function in sheep and provide evidence to support the hypothesis that the FecB mutation increases the BMP response of somatic cells when stimulated to differentiate by gonadotropins.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas Tipo I/genética , Proteínas Morfogenéticas Ósseas/farmacologia , Hormônio Foliculoestimulante/farmacologia , Células da Granulosa/efeitos dos fármacos , Hormônio Luteinizante/farmacologia , Mutação , Ovinos/genética , Células Tecais/efeitos dos fármacos , Fator de Crescimento Transformador beta/farmacologia , Animais , Proteína Morfogenética Óssea 2 , Proteína Morfogenética Óssea 4 , Proteína Morfogenética Óssea 6 , Proteínas Morfogenéticas Ósseas/análise , Feminino , Humanos , Fator de Crescimento Insulin-Like I/farmacologia , Ovário/química
13.
Oncogene ; 8(12): 3393-401, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8247542

RESUMO

The c-erbB-3 gene is a member of the EGF receptor family of membrane tyrosine kinases. Previous work has shown that the expression of this gene is frequently unregulated in human breast carcinoma-derived cell lines and in tumour biopsy material. As there is no evidence of gene amplification, we decided to examine the control of c-erbB-3 transcription in overexpressing cells. In this paper we describe the cloning of the c-erbB-3 promoter and its functional analysis within mammary-derived cell lines. We show that the promoter is more active in overexpressing cells and this is largely due to the action of the OB2-1 transcription factor which we have recently identified as mediating overexpression of the c-erbB-2 promoter in similar cell lines.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica/genética , Proteínas Proto-Oncogênicas/genética , Transcrição Gênica/genética , Sequência de Aminoácidos , Sequência de Bases , Neoplasias da Mama/química , Clonagem Molecular , Proteínas de Ligação a DNA/farmacologia , Receptores ErbB/análise , Humanos , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas/análise , Receptor ErbB-3 , Fatores de Transcrição/farmacologia , Células Tumorais Cultivadas
14.
Res Vet Sci ; 78(1): 9-15, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15500833

RESUMO

Olfactory glial cells have been the focus of much recent research interest because of their possible future use as cellular transplants in repair of spinal cord injury. Although olfactory glial cells can be collected from the olfactory bulb for in vitro culture, alternative sites would be preferable for safer surgical access. This study was designed to investigate the distribution of olfactory sensory neurons and olfactory glial cells within the canine peripheral olfactory system. Using immunohistochemistry and electron microscopy on perfused tissue we demonstrate that olfactory sensory neurons are found in both the caudal nasal and the frontal sinus epithelia. Olfactory ensheathing glia were found in the mucosa at both these sites implying that surgical access for harvesting cells for transplantation would be straightforward.


Assuntos
Cães/anatomia & histologia , Seio Frontal/inervação , Mucosa Nasal/inervação , Neuroglia/citologia , Neurônios Receptores Olfatórios/citologia , Animais , Proteína Glial Fibrilar Ácida/análise , Imuno-Histoquímica , Proteínas do Tecido Nervoso/análise , Molécula L1 de Adesão de Célula Nervosa/análise , Bulbo Olfatório/citologia , Proteína de Marcador Olfatório , Receptor de Fator de Crescimento Neural/análise , Ácidos Siálicos/análise
15.
J Econ Entomol ; 98(6): 1876-9, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16539107

RESUMO

Virus yield produced by dead larvae of balsam fir sawfly, Neodiprion abietis (Harris) (Hymenoptera: Diprionidae), that had been infected at four different larval stages (second, third, fourth, or fifth instar) with two virus concentrations (10(5) polyhedral inclusion bodies (PIB) /ml or 10(7) PIB/ml), were analyzed and compared to determine the effects of instar and amount of virus inoculum on virus production. The results indicate that both larval stage and inoculation dosage significantly affect virus yield. On average, each dead larva produced 1.36-12.21 x 10(7) PIB, depending upon larval age and virus concentration of inoculation. Although each dead larva produced more PIB when it was inoculated in the fourth or fifth stage, inoculation of these larvae did not result in the highest virus yield because of low larval mortality. In terms of net virus return, third instars would maximize virus yield when they are inoculated with a virus concentration that can cause 95-100% larval mortality.


Assuntos
Himenópteros/virologia , Nucleopoliedrovírus/metabolismo , Animais , Himenópteros/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento , Larva/virologia , Replicação Viral
16.
Appl Radiat Isot ; 62(2): 219-24, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15607452

RESUMO

Mezmaiskaya Cave has yielded more than 10,000 artifacts, thousands of very well preserved faunal remains, and hominin remains, found in seven Middle Paleolithic (Mousterian) and three Upper Paleolithic levels. A complete Neanderthal infant skeleton was preserved in anatomical juxtaposition lying on a large limestone block, overlain by the earliest Mousterian layer, Layer 3. Twenty-four skull fragments from a 1-2 year-old Neanderthal infant, showing post-mortem deformation, occurred in a pit originating in the Mousterian Layer 2 and penetrating into underlying layers 2A and 2B(1). Bone from Layer 2A was dated by AMS 14C at 35.8-36.3+/-0.5 kyr BP. Direct dating of Neanderthal bone from Layer 3 gave an age of 29 kyr, but that is now considered to be due to contamination by modern carbon. Fourteen large mammal teeth from Layers 2 through 3 have been dated by standard electron spin resonance (ESR). Low U concentrations in both the enamel and dentine ensure that ESR ages do not depend significantly on the U uptake model, but do depend strongly on the sedimentary dose rates. Assuming a sedimentary water concentration equal to 20 wt%, ESR ages for the Mousterian layers range from 36.2 to 73.0+/-5.0 ka.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica/métodos , Fósseis , Hominidae , Paleontologia/métodos , Determinação da Idade pelo Esqueleto/métodos , Determinação da Idade pelos Dentes/métodos , Animais , Arqueologia , Esmalte Dentário/química , Dentina/química , Humanos , Lactente , Federação Russa , Esqueleto , Crânio/química
17.
Appl Radiat Isot ; 62(2): 163-71, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15607443

RESUMO

The objective of the 3rd International Intercomparison on Electron Paramagnetic Resonance (EPR) Tooth Dosimetry was the evaluation of laboratories performing tooth enamel dosimetry below 300 mGy. Participants had to reconstruct the absorbed dose in tooth enamel from 11 molars, which were cut into two halves. One half of each tooth was irradiated in a 60Co beam to doses in the ranges of 30-100 mGy (5 samples), 100-300 mGy (5 samples), and 300-900 mGy (1 sample). Fourteen international laboratories participated in this intercomparison programme. A first analysis of the results and an overview of the essential features of methods applied in different laboratories are presented. The relative standard deviation of results of all methods was better than 27% for applied doses in the range of 79-704 mGy. In the analysis of the unirradiated tooth halves 8% of the samples were identified as outliers with additional absorbed dose above background dose.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica/métodos , Espectroscopia de Ressonância de Spin Eletrônica/normas , Radiometria/métodos , Radiometria/normas , Padrões de Referência , Dente/química , Dente/efeitos da radiação , Benchmarking/métodos , Carga Corporal (Radioterapia) , Humanos , Técnicas In Vitro , Internacionalidade , Garantia da Qualidade dos Cuidados de Saúde/métodos , Garantia da Qualidade dos Cuidados de Saúde/normas , Doses de Radiação , Eficiência Biológica Relativa , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco/métodos , Medição de Risco/normas , Sensibilidade e Especificidade
18.
Can Commun Dis Rep ; 41(11): 285-288, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-29769923

RESUMO

An international ship crew presented for medical care in Saint John, New Brunswick, following rapid onset of gastrointestinal and in some cases neurological and cardiac symptoms after a common fish meal. Ciguatera poisoning was identified as the cause of illness. This report describes the public health investigation and management of this incident, including collaboration between the implicated provincial and federal authorities.

19.
Int J Radiat Oncol Biol Phys ; 16(1): 263-9, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2912949

RESUMO

Good radiation treatment planning requires that the target volume be treated with a high and uniform dose of radiation while irradiating normal tissue as little as possible. Even if the merits of a given treatment plan are judged only on the appearance of isodose lines in one or a few planes it can sometimes be difficult for the experienced radiation oncologist to select the best of several alternative plans. If consideration is given to the entire spatial distribution of dose, however, the problem becomes far more difficult because of the enormous amount of data that must be evaluated. We believe that the lack of suitable methods to display these data has greatly contributed to the slow incorporation of 3D considerations into routine radiation treatment planning. In the past few years there have been great advances in both the theory of how to produce effective 3D displays and in the display hardware itself. In this paper we survey some of the methods used at the University of North Carolina, and show specific examples of how these displays can be used in radiation therapy treatment planning.


Assuntos
Gráficos por Computador , Neoplasias/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Assistida por Computador/métodos , Humanos , Imageamento por Ressonância Magnética , Neoplasias/diagnóstico , Neoplasias/diagnóstico por imagem , Tomografia Computadorizada por Raios X
20.
Mol Biochem Parasitol ; 72(1-2): 203-13, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8538690

RESUMO

Genetic diversity within and between tandemly arrayed copies of the Gp63 gene occurs in laboratory isolates of Leishmania spp., but the extent to which this represents natural genetic diversity has not been assessed. Here, the Gp63 locus is examined in 58 fresh isolates of L. peruviana, and clones derived from them, collected throughout the Peruvian Andes. Extensive polymorphism is observed, both in size of Gp63 containing chromosomes, and for restriction-fragment-length polymorphisms (RFLPs) at the Gp63 locus. All clones within an isolate are identical, including those with two distinct Gp63-hybridising chromosomal-sized pulsed-field gel electrophoresis (PFGE) bands, consistent with diploidy but with size differences in homologous chromosomes. For RFLP analysis, three enzymes were selected to cut within the coding region (PstI), in the intergenic region (SalI) and outside (EcoRI) the Gp63 gene cluster. PstI gave identical banding patterns across all isolates/clones. For EcoRI and SalI, all clones within an isolate were identical, but isolates were polymorphic for fragments at 13 (2-30 kb) and 8 (2.6-8.8 kb) different molecular mass locations generating 19 and 16 distinct RFLP patterns or genotypes for each enzyme, respectively. EcoRI restriction patterns, analysed by PFGE, were consistent with the presence of two clusters of Gp63 genes on each homologous chromosome, one contained within EcoRI fragments large enough to carry from 3 to 10 copies of the Gp63 gene, the second on fragments which could carry 1 or 2 copies of the gene. SalI patterns indicated variable restriction sites within clusters, but not within every intergenic region. A hierarchical analysis of variance of allele frequencies, expressed in terms of Wright's F-statistic, indicated significant barriers to gene flow at all levels, valleys within regions (north/south), villages within valleys, and individuals within villages. This extreme polymorphism at the Gp63 locus of L. peruviana demonstrates the great potential for generation of genetic diversity in parasite populations.


Assuntos
Antígenos de Protozoários/genética , Leishmania/genética , Metaloendopeptidases/genética , Polimorfismo de Fragmento de Restrição , Proteínas de Protozoários/genética , Animais , Variação Antigênica , Eletroforese em Gel de Campo Pulsado , Variação Genética , Leishmania/enzimologia , Leishmania/isolamento & purificação
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