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1.
J Intellect Disabil Res ; 64(7): 489-496, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32490559

RESUMO

BACKGROUND: It is unknown how the novel Coronavirus SARS-CoV-2, the cause of the current acute respiratory illness COVID-19 pandemic that has infected millions of people, affects people with intellectual and developmental disability (IDD). The aim of this study is to describe how individuals with IDD have been affected in the first 100 days of the COVID-19 pandemic. METHODS: Shortly after the first COVID-19 case was reported in the USA, our organisation, which provides continuous support for over 11 000 individuals with IDD, assembled an outbreak committee composed of senior leaders from across the health care organisation. The committee led the development and deployment of a comprehensive COVID-19 prevention and suppression strategy, utilising current evidence-based practice, while surveilling the global and local situation daily. We implemented enhanced infection control procedures across 2400 homes, which were communicated to our employees using multi-faceted channels including an electronic resource library, mobile and web applications, paper postings in locations, live webinars and direct mail. Using custom-built software applications enabling us to track patient, client and employee cases and exposures, we leveraged current public health recommendations to identify cases and to suppress transmission, which included the use of personal protective equipment. A COVID-19 case was defined as a positive nucleic acid test for SARS-CoV-2 RNA. RESULTS: In the 100-day period between 20 January 2020 and 30 April 2020, we provided continuous support for 11 540 individuals with IDD. Sixty-four per cent of the individuals were in residential, community settings, and 36% were in intermediate care facilities. The average age of the cohort was 46 ± 12 years, and 60% were male. One hundred twenty-two individuals with IDD were placed in quarantine for exhibiting symptoms and signs of acute infection such as fever or cough. Sixty-six individuals tested positive for SARS-CoV-2, and their average age was 50. The positive individuals were located in 30 different homes (1.3% of total) across 14 states. Fifteen homes have had single cases, and 15 have had more than one case. Fifteen COVID-19-positive individuals were hospitalised. As of 30 April, seven of the individuals hospitalised have been discharged back to home and are recovering. Five remain hospitalised, with three improving and two remaining in intensive care and on mechanical ventilation. There have been three deaths. We found that among COVID-19-positive individuals with IDD, a higher number of chronic medical conditions and male sex were characteristics associated with a greater likelihood of hospitalisation. CONCLUSIONS: In the first 100 days of the COVID-19 outbreak in the USA, we observed that people with IDD living in congregate care settings can benefit from a coordinated approach to infection control, case identification and cohorting, as evidenced by the low relative case rate reported. Male individuals with higher numbers of chronic medical conditions were more likely to be hospitalised, while most younger, less chronically ill individuals recovered spontaneously at home.


Assuntos
Betacoronavirus , Doença Crônica/epidemiologia , Infecções por Coronavirus/epidemiologia , Cuidados Críticos/estatística & dados numéricos , Deficiências do Desenvolvimento/epidemiologia , Surtos de Doenças/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Controle de Infecções/estatística & dados numéricos , Deficiência Intelectual/epidemiologia , Pneumonia Viral/epidemiologia , Adulto , COVID-19 , Comorbidade , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/terapia , Instituições Residenciais/estatística & dados numéricos , SARS-CoV-2 , Fatores Sexuais , Estados Unidos/epidemiologia
2.
Neurobiol Learn Mem ; 152: 20-31, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29723671

RESUMO

When objects transform into different views, some properties are maintained, such as whether the edges are convex or concave, and these non-accidental properties are likely to be important in view-invariant object recognition. The metric properties, such as the degree of curvature, may change with different views, and are less likely to be useful in object recognition. It is shown that in a model of invariant visual object recognition in the ventral visual stream, VisNet, non-accidental properties are encoded much more than metric properties by neurons. Moreover, it is shown how with the temporal trace rule training in VisNet, non-accidental properties of objects become encoded by neurons, and how metric properties are treated invariantly. We also show how VisNet can generalize between different objects if they have the same non-accidental property, because the metric properties are likely to overlap. VisNet is a 4-layer unsupervised model of visual object recognition trained by competitive learning that utilizes a temporal trace learning rule to implement the learning of invariance using views that occur close together in time. A second crucial property of this model of object recognition is, when neurons in the level corresponding to the inferior temporal visual cortex respond selectively to objects, whether neurons in the intermediate layers can respond to combinations of features that may be parts of two or more objects. In an investigation using the four sides of a square presented in every possible combination, it was shown that even though different layer 4 neurons are tuned to encode each feature or feature combination orthogonally, neurons in the intermediate layers can respond to features or feature combinations present is several objects. This property is an important part of the way in which high capacity can be achieved in the four-layer ventral visual cortical pathway. These findings concerning non-accidental properties and the use of neurons in intermediate layers of the hierarchy help to emphasise fundamental underlying principles of the computations that may be implemented in the ventral cortical visual stream used in object recognition.


Assuntos
Encéfalo/fisiologia , Modelos Neurológicos , Neurônios/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Reconhecimento Psicológico/fisiologia , Percepção de Forma/fisiologia , Humanos , Redes Neurais de Computação , Aprendizado de Máquina não Supervisionado , Vias Visuais/fisiologia
3.
Neurobiol Learn Mem ; 145: 205-221, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29042296

RESUMO

A fundamental question is how the cerebral neocortex operates functionally, computationally. The cerebral neocortex with its superficial and deep layers and highly developed recurrent collateral systems that provide a basis for memory-related processing might perform somewhat different computations in the superficial and deep layers. Here we take into account the quantitative connectivity within and between laminae. Using integrate-and-fire neuronal network simulations that incorporate this connectivity, we first show that attractor networks implemented in the deep layers that are activated by the superficial layers could be partly independent in that the deep layers might have a different time course, which might because of adaptation be more transient and useful for outputs from the neocortex. In contrast the superficial layers could implement more prolonged firing, useful for slow learning and for short-term memory. Second, we show that a different type of computation could in principle be performed in the superficial and deep layers, by showing that the superficial layers could operate as a discrete attractor network useful for categorisation and feeding information forward up a cortical hierarchy, whereas the deep layers could operate as a continuous attractor network useful for providing a spatially and temporally smooth output to output systems in the brain. A key advance is that we draw attention to the functions of the recurrent collateral connections between cortical pyramidal cells, often omitted in canonical models of the neocortex, and address principles of operation of the neocortex by which the superficial and deep layers might be specialized for different types of attractor-related memory functions implemented by the recurrent collaterals.


Assuntos
Córtex Cerebral/fisiologia , Memória/fisiologia , Modelos Neurológicos , Animais , Humanos , Redes Neurais de Computação , Vias Neurais/fisiologia
4.
Phys Rev Lett ; 116(17): 172501, 2016 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-27176517

RESUMO

Precision measurements of superallowed Fermi ß-decay transitions, particularly for the lightest superallowed emitters ^{10}C and ^{14}O, set stringent limits on possible scalar current contributions to the weak interaction. In the present work, a discrepancy between recent measurements of the ^{10}C half-life is addressed through two high-precision half-life measurements, via γ-ray photopeak and ß counting, that yield consistent results for the ^{10}C half-life of T_{1/2}=19.2969±0.0074 s and T_{1/2}=19.3009±0.0017 s, respectively. The latter is the most precise superallowed ß-decay half-life measurement reported to date and the first to achieve a relative precision below 10^{-4}. A fit to the world superallowed ß-decay data including the ^{10}C half-life measurements reported here yields b_{F}=-0.0018±0.0021 (68% C.L.) for the Fierz interference term and C_{S}/C_{V}=+0.0009±0.0011 for the ratio of the weak scalar to vector couplings assuming left-handed neutrinos.

5.
Scand J Med Sci Sports ; 26(3): 329-37, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25772829

RESUMO

Muscle damage caused through impacts in rugby union is known to increase oxidative stress and inflammation. Pterins have been used clinically as markers of oxidative stress, inflammation, and neurotransmitter synthesis. This study investigates the release of myoglobin from muscle tissue due to force-related impacts and how it is related to the subsequent oxidation of 7,8-dihydroneopterin to specific pterins. Effects of iron and myoglobin on 7,8-dihydroneopterin oxidation were examined in vitro via strong cation-exchange high-performance liquid chromatography (SCX-HPLC) analysis of neopterin, xanthopterin, and 7,8-dihydroxanthopterin. Urine samples were collected from 25 professional rugby players pre and post four games and analyzed for myoglobin by enzyme-linked immunosorbent assay, and 7,8-dihydroneopterin oxidation products by HPLC. Iron and myoglobin oxidized 7,8-dihydroneopterin to neopterin, xanthopterin, and 7,8-dihydroxanthopterin at concentrations at or above 10 µM and 50 µg/mL, respectively. All four games showed significant increases in myoglobin, neopterin, total neopterin, biopterin, and total biopterin, which correlated between each variable (P < 0.05). Myoglobin and iron facilitate 7,8-dihydroneopterin oxidation to neopterin and xanthopterin. In vivo delocalization of myoglobin due to muscle damage may contribute to oxidative stress and inflammation after rugby. Increased concentrations of biopterin and total biopterin may indicate production of nitric oxide and monoamine neurotransmitters in response to the physical stress.


Assuntos
Traumatismos em Atletas/metabolismo , Futebol Americano/lesões , Músculo Esquelético/fisiopatologia , Mioglobina/metabolismo , Neopterina/análogos & derivados , Pterinas/urina , Adulto , Atletas , Traumatismos em Atletas/urina , Biomarcadores/urina , Biopterinas/metabolismo , Biopterinas/urina , Cromatografia Líquida de Alta Pressão , Ensaio de Imunoadsorção Enzimática , Humanos , Ferro/metabolismo , Masculino , Neopterina/metabolismo , Neopterina/urina , Oxirredução , Estresse Oxidativo , Pterinas/metabolismo , Xantopterina/metabolismo , Xantopterina/urina , Adulto Jovem
6.
J Am Vet Med Assoc ; 260(13): 1589-1596, 2022 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-35895801

RESUMO

Leptospirosis is a quintessential one health disease of humans and animals caused by pathogenic spirochetes of the genus Leptospira. Intra- and interspecies transmission is dependent on 1) reservoir host animals in which organisms replicate and are shed in urine over long periods of time, 2) the persistence of spirochetes in the environment, and 3) subsequent human-animal-environmental interactions. The combination of increased flooding events due to climate change, changes in human-animal-environmental interactions as a result of the pandemic that favor a rise in the incidence of leptospirosis, and under-recognition of leptospirosis because of nonspecific clinical signs and severe signs that resemble COVID-19 represents a "perfect storm" for resurgence of leptospirosis in people and domestic animals. Although often considered a disease that occurs in warm, humid climates with high annual rainfall, pathogenic Leptospira spp have recently been associated with disease in animals and humans that reside in semiarid regions like the southwestern US and have impacted humans that have a wide spectrum of socioeconomic backgrounds. Therefore, it is critical that physicians, veterinarians, and public health experts maintain a high index of suspicion for the disease regardless of geographic and socioeconomic circumstances and work together to understand outbreaks and implement appropriate control measures. Over the last decade, major strides have been made in our understanding of the disease because of improvements in diagnostic tests, molecular epidemiologic tools, educational efforts on preventive measures, and vaccines. These novel approaches are highlighted in the companion Currents in One Health by Sykes et al, AJVR, September 2022.


Assuntos
COVID-19 , Leptospira , Leptospirose , Saúde Única , Humanos , Animais , COVID-19/veterinária , Leptospirose/veterinária , Surtos de Doenças , Zoonoses/epidemiologia
7.
Mar Pollut Bull ; 181: 113919, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35816822

RESUMO

Mercury is a pervasive environmental contaminant that can negatively impact seabirds. Here, we measure total mercury (THg) concentrations in red blood cells (RBCs) from breeding brown skuas (Stercorarius antarcticus) (n = 49) at Esperanza/Hope Bay, Antarctic Peninsula. The aims of this study were to: (i) analyse RBCs THg concentrations in relation to sex, year and stable isotope values of carbon (δ13C) and nitrogen (δ15N); and (ii) examine correlations between THg, body condition and breeding success. RBC THg concentrations were positively correlated with δ15N, which is a proxy of trophic position, and hence likely reflects the biomagnification process. Levels of Hg contamination differed between our study years, which is likely related to changes in diet and distribution. RBC THg concentrations were not related to body condition or breeding success, suggesting that Hg contamination is currently not a major conservation concern for this population.


Assuntos
Charadriiformes , Mercúrio , Poluentes Químicos da Água , Animais , Ecologia , Monitoramento Ambiental , Cadeia Alimentar , Isótopos/análise , Mercúrio/análise , Poluentes Químicos da Água/análise
8.
Hum Exp Toxicol ; 38(6): 746-750, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30935228

RESUMO

The topic of hormesis research funding has been a focus of deliberation within the scientific community for several decades. A common assumption/belief is that most hormesis research is funded by the private sector. With this assumption may emerge questions revolving around potential bias of such research. To provide some clarification to this issue, all hormesis research articles were obtained through online databases for 5-year increments starting with 1995 and ending with 2015 and were subsequently categorized by their funding source. A total of 710 articles were found for those years and 383 of those reported information on funding sources. Reporting funding is not required by law and until more recently was not encouraged or required by funders, research institutions, and/or scientific publishers. The analysis revealed that the assumption that the majority of hormesis research has been privately funded was not supported, with the public sector (i.e. federal and state governmental agencies) exclusively contributing to 78% of the reported research funding. Going forward, funding transparency for scientific research as a whole is essential within the scientific community as it may affect how research may be perceived, accepted, and applied.


Assuntos
Hormese , Apoio à Pesquisa como Assunto/tendências , Governo Federal , Setor Público , Governo Estadual
9.
Child Care Health Dev ; 34(2): 185-93, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18257791

RESUMO

BACKGROUND: The life expectancy of children with physical disabilities now extends into adulthood and has been accompanied by the transfer of rehabilitation services from institutions to the home. Thus, families must increasingly partner with health service providers to promote their child's health and prevent the development of secondary conditions that may contribute to heart disease, stroke, respiratory diseases, low endurance and emotional difficulties. AIM: To investigate within a family context the health promotion efforts of parents on behalf of a child with a physical disability. METHOD: The Long Interview Method was used to interview 15 families (11 two-parent and 4 single-parent) having a child 11-16 years of age with a physical disability including cerebral palsy (7), spina bifida (3), muscular dystrophy (3) and other conditions (2). RESULTS: Parents' health promotion efforts were characterized by three main themes. First, parents emphasized traditional lifestyle health behaviours including nutrition, physical activity, tobacco, alcohol and drug use, and personal hygiene. Second, parents tried to foster their adolescent's social life and friendships. They expressed particular concern about how, and if, their child would develop a sense of purpose and have a productive future. Third, parents invested a great deal of effort into observing daily routines, making arrangements for their child's social inclusion and supporting their child in a way that balanced independence with safety and energy conservation. CONCLUSIONS: Parents recognize that their child with a physical disability faces greater obstacles, and work hard at health promotion. Healthcare workers need to work with parents to: (1) provide information about specific lifestyle health behaviours including nutrition, physical activity and sexuality; (2) advocate for resources to foster social inclusion; and (3) discuss family strategies that balance parental involvement with their child's need for independence and energy conservation for daily activities.


Assuntos
Crianças com Deficiência , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde , Relações Pais-Filho , Poder Familiar/psicologia , Pais/psicologia , Adolescente , Adulto , Criança , Família , Feminino , Humanos , Relações Interpessoais , Estilo de Vida , Masculino , Inquéritos e Questionários
11.
Postgrad Med J ; 83(986): e8, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18057166

RESUMO

We present here a patient with end stage renal failure who received two weeks antimalarial prophylaxis at full dose leading to life threatening toxicity with severe acute megaloblastic anaemia, symptomatic pancytopenia and exfoliative dermatitis. Prompt recognition and treatment can rapidly reverse these fatal effects but more importantly, education of patients before travel is imperative in preventing such events.


Assuntos
Anemia Megaloblástica/induzido quimicamente , Antimaláricos/efeitos adversos , Dermatite Esfoliativa/induzido quimicamente , Falência Renal Crônica/complicações , Malária/tratamento farmacológico , Pancitopenia/induzido quimicamente , Adulto , Cloroquina/efeitos adversos , Quimioterapia Combinada , Humanos , Malária/complicações , Masculino , Proguanil/efeitos adversos
12.
Appl Radiat Isot ; 65(3): 345-9, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17098433

RESUMO

Cross-sections for the production of (181)Re, (182m)Re, (182g)Re, (183)Re, (184)Re, and (186)Re from proton bombardment of natural tungsten have been measured using the stacked foil technique for proton energies up to 17.6 MeV. Results are compared with the theoretical excitation functions as calculated by the EMPIRE II code (version 2.19) and experimental literature values. Results are in strong agreement with some of the previously reported literature as well at theoretical calculations for multiple reactions providing for more reliable estimates for the (186)W(p,n)(186)Re reaction.


Assuntos
Prótons , Radioisótopos , Rênio , Tungstênio/efeitos da radiação , Radioimunoterapia
13.
Cytogenet Genome Res ; 113(1-4): 336-44, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16575198

RESUMO

We analyse the evolution of X chromosome-linked imprinting by modifying our previous model of imprinting of autosomal genes that influence the trade-off between maternal fecundity and offspring viability through alterations in maternal investment (Mills and Moore, 2004). Unlike previous genetic models, we analyse X-linked imprinting in the context of populations at equilibrium for either autosomal or X-linked biallelically expressed alleles at loci that influence the fecundity/viability trade-off. We show that selection under parental conflict over maternal investment in offspring can parsimoniously explain the occurrence of sex-specific gene expression patterns, without a requirement to postulate direct selection for sexual dimorphism mediated through imprinting. We note that sex chromosome imprinting causes a small distortion of the post-weaning sex ratio, providing a possible selection pressure against the evolution of X-linked imprints. We discuss our conclusions in the context of recent reports of imprinting of mouse X-linked Xlr genes.


Assuntos
Evolução Molecular , Inativação Gênica , Impressão Genômica , Cromossomo X , Animais , Feminino , Masculino , Mamíferos , Comportamento Materno , Caracteres Sexuais
14.
J Clin Oncol ; 13(3): 588-95, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7884420

RESUMO

PURPOSE: To evaluate the outcome of patients with relapsed or resistant non-Hodgkin's lymphoma (NHL) undergoing high-dose chemotherapy and autologous bone marrow transplantation (ABMT) and to determine the main prognostic factors. PATIENTS AND METHODS: One hundred seven patients with relapsed or resistant intermediate-/high-grade NHL underwent high-dose carmustine, etoposide, cytarabine, and melphalan (BEAM) chemotherapy and ABMT at University College Hospitals between September 1981 and February 1993. The minimum follow-up duration of all patients is 6 months. RESULTS: At 3 months, the overall response rate to BEAM and ABMT was 73% (41% complete response and 32% partial response). The 5-year actuarial overall survival and progression-free survival rates were 41% and 35%, respectively. The early procedure-related mortality rate was 7% (eight of 107 patients). On multivariate analysis, the main prognostic factor was disease status at the time of ABMT. Patients with chemosensitive disease had an actuarial 5-year survival rate of 49% at 5 years compared with 13% for those with chemoresistant disease (P < .001). For patients considered to have chemosensitive disease at the time of transplantation, there is a significant difference in the actuarial progression-free survival rates for those who received high-dose therapy after attaining a partial response to first-line therapy (69% at 5 years) as compared with those with sensitive but relapsed disease (32% at 5 years) (P = .003). CONCLUSION: Patients with chemosensitive disease benefit most from high-dose chemotherapy, and those who receive such therapy early after achieving a partial response to first-line therapy have a high rate of cure.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Medula Óssea , Linfoma não Hodgkin/terapia , Adolescente , Adulto , Carmustina/administração & dosagem , Citarabina/administração & dosagem , Intervalo Livre de Doença , Etoposídeo/administração & dosagem , Feminino , Seguimentos , Humanos , Linfoma não Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/mortalidade , Masculino , Melfalan/administração & dosagem , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Recidiva , Indução de Remissão , Taxa de Sobrevida , Transplante Autólogo
15.
J Clin Oncol ; 12(8): 1693-702, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7518861

RESUMO

PURPOSE: The aims of this study were to develop a simplified, safe, and cost-effective peripheral-blood progenitor-cell (PBPC) mobilization protocol. PATIENTS AND METHODS: Twenty-six patients with relapsed or resistant lymphomas were entered onto a sequential cohort study in which schedules of various granulocyte colony-stimulating factor (G-CSF) were administered after cyclophosphamide 1.5 g/m2. Hematologic recovery after high-dose carmustine (BCNU) etoposide, cytarabine, and melphalan (BEAM) chemotherapy was compared with that of 46 patients who received autologous bone marrow transplantation (ABMT) without growth factors and 28 patients who received ABMT followed by G-CSF. RESULTS: When G-CSF (10 micrograms/kg/d) was administered from the day after the cyclophosphamide, neutropenia developed on day 8 followed by an abrupt increase in the WBC count. The optimal time for PBPC harvesting was the day on which the postnadir WBC count was greater than 8.0 x 10(9)/L, as shown by CD34+ cell counts and granulocytic-macrophage colony-forming cell (GM-CFC) assays. The reproducibility of the response was such that routine monitoring of CD34+ cell counts and GM-CFC was not necessary. A single leukapheresis on this day was adequate for prompt hematologic engraftment, and posttransplant G-CSF made little further impact on the rapid recovery. Compared with both control groups, the use of PBPC led to more rapid neutrophil recovery, markedly accelerated platelet recovery, less use of antimicrobial agents and parenteral nutrition, and more than 10 days earlier discharge from hospital. All of these differences were highly significant (P < .01). CONCLUSION: A simplified mobilization protocol is described that requires only one apheresis to achieve rapid hematologic engraftment.


Assuntos
Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Transplante de Células-Tronco Hematopoéticas , Doença de Hodgkin/terapia , Leucaférese/métodos , Linfoma não Hodgkin/terapia , Adulto , Estudos de Coortes , Ciclofosfamida/farmacologia , Feminino , Fator Estimulador de Colônias de Granulócitos/farmacologia , Doença de Hodgkin/sangue , Humanos , Contagem de Leucócitos/efeitos dos fármacos , Linfoma não Hodgkin/sangue , Masculino , Recidiva
16.
Gene ; 239(1): 81-90, 1999 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-10571037

RESUMO

The telomere-associated protein TRF2 binds as a homodimer to double-stranded (TTAGGG)n arrays in vitro and localises to chromosome ends in vivo. Inhibition of TRF2 in human cell lines and recent electron microscopy analyses suggest that TRF2 plays a crucial role in the maintenance of telomere integrity. To study the role of TRF2 in vertebrate telomere biology using an alternative model system, we report the isolation and characterisation of the chicken TRF2 locus. The TRF2 protein is highly conserved between mammals and birds, particularly within the dimerisation and myb-type DNA binding domains. However, the chicken ORF predicts an additional protein domain consisting of 15 copies of a degenerate 13 amino acid repeat. Indirect immunofluorescence reveals the localisation of a FLAG-tagged version of the chicken TRF2 protein at chromosome ends in both chicken and human cells suggesting that the protein is functionally conserved.


Assuntos
Proteínas de Ligação a DNA/genética , Telômero/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular Transformada , Galinhas , Mapeamento Cromossômico , Clonagem Molecular , Códon de Iniciação , Sequência Conservada , DNA Complementar/química , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Éxons , Regulação da Expressão Gênica no Desenvolvimento , Genes/genética , Humanos , Íntrons , Camundongos , Dados de Sequência Molecular , Biossíntese de Proteínas , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Proteína 2 de Ligação a Repetições Teloméricas , Células Tumorais Cultivadas , Vertebrados/genética
17.
Am J Clin Nutr ; 40(3): 522-7, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6540979

RESUMO

The effect of varying concentrations of ascorbic acid on the absorption of iron from a soy-based infant milk formula containing 6 mg iron/100 g was examined in 64 adult Indian females using the extrinsic radioactive tag method. The corrected geometric mean absorption from the basic soy formula was only 1.8%. Addition of ascorbic acid in a concentration of 40 mg/100 g, did not significantly increase absorption (3.3%; t = 1.8, p greater than 0.07) but raising the concentration to 80 mg/100 g did so (6.9%; t = 2.4, p less than 0.02). No further significant increase was noted when the concentration of ascorbic acid was increased to 160 mg/100 g (7.7%; t = 0.4, p greater than 0.7). The inhibitory effect of soy on iron absorption was further demonstrated by a direct comparison between the soy-based formula and a similar product based on cows' milk. The comparison was made at two concentrations of ascorbic acid. At 40 mg/100 g the geometric mean iron absorption from the soy formula was 2.4% compared with 5.3% from the milk formula (t = 2.8, p less than 0.02), while the corresponding values at 80 mg ascorbic acid/100 g were 7.2 and 19.5%, respectively (t = 3.4, p less than 0.02). The present results confirm the marked inhibitory effect of soy protein on iron absorption and calculations from the absorption figures suggest that such formulas should contain at least 12 mg/100 g iron together with ascorbic acid in a molar ratio of approximately 4:1 if they are to be adequate in terms of iron nutrition.


Assuntos
Anemia Hipocrômica/prevenção & controle , Ácido Ascórbico/administração & dosagem , Alimentos Infantis , Ferro/metabolismo , Animais , Bovinos , Humanos , Lactente , Absorção Intestinal , Leite , Glycine max
18.
Chest ; 87(3): 330-3, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3882350

RESUMO

Breathing against positive expiratory pressure has been used to improve gas exchange in many forms of pulmonary edema, and forced expiration against resistance during exercise has been advocated for climbing at high altitude as a method to optimize performance. To evaluate the effect of expiratory positive airway pressure (EPAP) on climbers with high altitude pulmonary edema (HAPE) and on exercise at high altitude, we studied four climbers with HAPE at rest and 13 healthy climbers during exercise on a bicycle ergometer at 4400 m. We measured minute ventilation (VI, L/min), arterial oxygen saturation (SaO2 percent), end-tidal carbon dioxide (PACO2, mm Hg), respiratory rate (RR), and heart rate (HR) during the last minute of a five minute interval at rest in the climbers with HAPE, and at rest, 300, and 600 kpm/minute workloads on a bicycle ergometer in the healthy subjects. The HAPE subjects demonstrated an increased SaO2 percent, no change in HR or VI, and a decrease in RR on EPAP as compared to control. In normal subjects, SaO2 percent, VI, and heart rate were significantly higher on EPAP 10 cm H2O than 0 cm H2O control (p less than 0.01, 0.01, and 0.05, respectively). The RR and PaCO2 were not significantly different. In summary, EPAP improves gas exchange in HAPE subjects at rest. The EPAP in normal subjects at high altitude resulted in a higher SaO2 percent at the expense of a higher VI and higher HR. These results suggest that the work of breathing is higher and the stroke volume lower on EPAP. The positive pressure mask may be an effective temporizing measure for victims of HAPE who cannot immediately go to a lower altitude.


Assuntos
Doença da Altitude/fisiopatologia , Hipóxia/fisiopatologia , Esforço Físico , Respiração com Pressão Positiva , Edema Pulmonar/fisiopatologia , Adulto , Doença da Altitude/complicações , Feminino , Humanos , Medidas de Volume Pulmonar , Masculino , Montanhismo , Edema Pulmonar/etiologia , Troca Gasosa Pulmonar
19.
Bone Marrow Transplant ; 13(5): 511-7, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8054904

RESUMO

Pituitary-gonadal (P-G) function was evaluated 0-3 months before and 3-4 months after bone marrow transplantation (BMT) in 15 post-menarcheal females aged 17-30 (21.6 +/- 0.34) years with haematological malignancies. All patients had evidence of gonadal insufficiency prior to BMT in that their basal and human menopausal gonadotrophin (HMG)-stimulated oestradiol (E2) levels were significantly lower than those of control subjects. The patients also had markedly higher basal FSH levels and exaggerated responses to 100 micrograms iv gonadotrophin release hormone bolus compared with those of control subjects. However, the conditioning regimens employed prior to BMT, i.e. cytotoxic chemotherapy (CT) and total body irradiation (TBI), acting either singly or in combination, caused further ovarian damage. As a result, their gonadotrophins rose further into the menopausal range. Their oestradiol secretion diminished and ovaries became almost unresponsive 3-4 months after BMT. Pelvic ultrasound undertaken in 5 patients before and after BMT demonstrated a reduction in ovarian size associated with follicular depletion. All patients developed menopausal symptoms and became amenorrhoeic during this period. Contrary to expectation, the hormonal changes occurring acutely were similar in patients undergoing radiation-based regimens and those conditioned with high-dose chemotherapy alone. Also, the severity of ovarian dysfunction appeared independent of age at transplantation, the nature of the conditioning-regimen or the type of transplant. Gonadotrophic, thyrotrophic, lactotrophic and adrenocorticotrophic secretions were unaffected. These data indicate that the ovary suffers an acute insult during short-term chemotherapy but the anterior pituitary gland retains its trophic hormone reserve and secretory capacity.


Assuntos
Antineoplásicos/efeitos adversos , Transplante de Medula Óssea , Ovário/fisiopatologia , Hipófise/fisiopatologia , Irradiação Corporal Total , Adolescente , Adulto , Terapia Combinada , Feminino , Humanos , Leucemia/fisiopatologia , Leucemia/terapia , Linfoma/fisiopatologia , Linfoma/terapia , Menstruação , Ovário/efeitos dos fármacos , Ovário/efeitos da radiação , Pelve/diagnóstico por imagem , Hipófise/efeitos dos fármacos , Hipófise/efeitos da radiação , Estudos Prospectivos , Transplante Autólogo , Transplante Homólogo , Ultrassonografia
20.
Bone Marrow Transplant ; 13(5): 519-22, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8054905

RESUMO

Thirteen post-pubertal male patients aged 17-25 years were assessed for pituitary-gonadal function 0-3 months prior to and 2-3 months post-bone marrow transplantation for haematological malignancy. All patients had multiagent cytotoxic treatment prior to transplantation and 30% were found to have germ cell dysfunction with abnormal semen parameters before high-dose therapy indicating damage to the germinal epithelium. They also had evidence of reduced Leydig cell reserve even before transplantation. During transplantation all patients sustained sustained gonadal injury, the effect on their germ cells being more pronounced than on the Leydig cells. Fifty per cent had reduction in testicular volume and all had azoospermia 2-3 months post-transplantation. Our results indicate that short-term chemoradiotherapy causes profound damage to the germ cell compartment of the testis, with less severe damage to the Leydig cells, but no overt injury to the anterior pituitary gland. The changes appeared to be identical in patients conditioned with total body irradiation-based protocols and those who received only high-dose chemotherapy prior to bone marrow transplantation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Transplante de Medula Óssea/efeitos adversos , Células Intersticiais do Testículo/efeitos dos fármacos , Linfoma/terapia , Espermatozoides/efeitos dos fármacos , Adolescente , Adulto , Carmustina/efeitos adversos , Terapia Combinada , Citarabina/efeitos adversos , Etoposídeo/efeitos adversos , Hormônio Foliculoestimulante/sangue , Humanos , Células Intersticiais do Testículo/fisiologia , Hormônio Luteinizante/sangue , Linfoma/fisiopatologia , Masculino , Melfalan/efeitos adversos , Espermatozoides/fisiologia , Transplante Autólogo
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