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1.
Hum Reprod ; 38(7): 1325-1331, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37208860

RESUMO

STUDY QUESTION: How often do patients undergoing frozen embryo transfer (FET) after preimplantation genetic testing for aneuploidy (PGT-A) choose to select for sex and do sex selection rates differ before and after successful delivery of a first baby? SUMMARY ANSWER: When a choice was available between male and female embryos, patients selected the sex more frequently when trying to conceive the second child (62%) as compared to the first child (32.4%) and most commonly selected for the opposite sex of the first child. WHAT IS KNOWN ALREADY: Sex selection is widely available in US fertility clinics. However, the rate of sex selection for patients undergoing FET after PGT-A is unknown. STUDY DESIGN, SIZE, DURATION: This is a retrospective cohort study of 585 patients that took place between January 2013 and February 2021. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study took place at a single, urban academic fertility center in the USA. Patients were included if they had a live birth after single euploid FET and returned for at least one subsequent euploid FET. The primary outcomes were the rates of sex selection for first versus second baby. Secondary outcomes were rate of selection for same versus opposite sex as first live birth and overall rate of selection for males versus females. MAIN RESULTS AND THE ROLE OF CHANCE: Five hundred and eighty-five patients underwent a total of 1560 single euploid FETs resulting in either one or two live births. A choice between male and female euploid embryos was available for 919 FETs (first child: 67.5% (519/769) versus second child: 50.6% (400/791), P < 0.01). When a choice was available, patients selected the sex more frequently when trying to conceive the second child (first child: 32.4% (168/519) versus second child: 62.0% (248/400), P < 0.01). When sex was selected after first live birth, the opposite sex of the first child was selected 81.8% (203/248 FETs) of the time. Of transfers that involved sex selection, rates of male and female selection were similar for the first child, but selection for females was greater for the second child (first child: 51.2% (86/168) male versus 48.9% (82/168) female, second child: 41.1% (102/248) male versus 58.9% (146/248) female, P < 0.04). LIMITATIONS, REASONS FOR CAUTION: The study was performed at one urban academic medical center in the Northeastern US, which may limit generalizability to other settings where PGT-A may be performed less frequently, or sex selection may be limited or not permitted. In addition, we could not reliably account for whether patients or their partners had prior children and if so, of what sex. WIDER IMPLICATIONS OF THE FINDINGS: Patients undergoing PGT-A with both male and female euploid embryos were more likely to select for sex when attempting a second child and usually selected for the opposite sex of their first child. These findings highlight the potential for family balancing for patients who undergo PGT-A in settings where sex selection is permitted. STUDY FUNDING/COMPETING INTEREST(S): This study received no funding. The authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Diagnóstico Pré-Implantação , Pré-Seleção do Sexo , Gravidez , Criança , Humanos , Feminino , Masculino , Estudos Retrospectivos , Implantação do Embrião , Testes Genéticos , Aneuploidia , Diagnóstico Pré-Implantação/métodos , Blastocisto
2.
Dis Aquat Organ ; 156: 99-114, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38095365

RESUMO

Mortality of dolphins in fishing operations is often under-estimated, as shown by studies of beach-washed carcasses. Linking evidence obtained during necropsies with fishing method is fundamental to understanding the extent of mortality and the manner in which animals die. The South Australian Sardine Fishery (SASF) has operated a purse-seine industry since 1991. This study characterised injuries, pathological changes and life history of 49 dead dolphins collected from SASF during 2006-2019. Histology examination was conducted on 25 animals. Neonates, calves and juveniles accounted for 63% of the sample. Of mature females (n = 14), 11 were pregnant or lactating, with cryptic mortality estimated to be 20% of dolphins studied. Body condition was robust in 48 dolphins. Net marks were seen on 82%, mostly on the head, trunk and peduncle. Broken/missing teeth were noted in 63%. All dolphins had subdermal haemorrhage (moderate to severe in 96%), particularly around the head. Deep haemorrhage was common, including around occipital and flipper condyles, and organs. Copious fluid was present in the thoracic (pleural) and abdominal (ascites) cavities of half of the dolphins. Within the lungs, watery fluid and froth were observed in 100 and 39%, respectively. Recent bone fractures were documented in 43% of dolphins, mostly associated with haemorrhage. Severe blunt trauma appeared to be the primary cause of death, and 10 dolphins also had other significant pathologies. Visceral organ congestion and mild cardiomyopathy were observed. Stomachs contained prey remains in 75% of cases. The results of this study may help identify unreported purse-seine mortalities washed up in South Australia and elsewhere.


Assuntos
Golfinhos Comuns , Golfinhos , Feminino , Animais , Austrália do Sul/epidemiologia , Austrália , Pesqueiros , Lactação , Hemorragia/veterinária
3.
BJOG ; 128(11): 1804-1812, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33993600

RESUMO

OBJECTIVE: To report on the effectiveness of a standardised core Maternity Waiting Home (MWH) model to increase facility deliveries among women living >10 km from a health facility. DESIGN: Quasi-experimental design with partial randomisation at the cluster level. SETTING: Seven rural districts in Zambia. POPULATION: Women delivering at 40 health facilities between June 2016 and August 2018. METHODS: Twenty intervention and 20 comparison sites were used to test whether MWHs increased facility delivery for women living in rural Zambia. Difference-in-differences (DID) methodology was used to examine the effectiveness of the core MWH model on our identified outcomes. MAIN OUTCOME MEASURES: Differences in the change from baseline to study period in the percentage of women living >10 km from a health facility who: (1) delivered at the health facility, (2) attended a postnatal care (PNC) visit and (3) were referred to a higher-level health facility between intervention and comparison group. RESULTS: We detected a significant difference in the percentage of deliveries at intervention facilities with the core MWH model for all women living >10 km away (DID 4.2%, 95% CI 0.6-7.6, P = 0.03), adolescent women (<18 years) living >10 km away (DID 18.1%, 95% CI 6.3-29.8, P = 0.002) and primigravida women living >10 km away (DID 9.3%, 95% CI 2.4-16.4, P = 0.01) and for women attending the first PNC visit (DID 17.8%, 95% CI 7.7-28, P < 0.001). CONCLUSION: The core MWH model was successful in increasing rates of facility delivery for women living >10 km from a healthcare facility, including adolescent women and primigravidas and attendance at the first PNC visit. TWEETABLE ABSTRACT: A core MWH model increased facility delivery for women living >10 km from a health facility including adolescents and primigravidas in Zambia.


Assuntos
Parto Obstétrico/estatística & dados numéricos , Serviços de Saúde Materna/estatística & dados numéricos , Assistência Centrada no Paciente/estatística & dados numéricos , Serviços de Saúde Rural/estatística & dados numéricos , População Rural/estatística & dados numéricos , Adolescente , Adulto , Análise por Conglomerados , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Gravidez , Adulto Jovem , Zâmbia
4.
Proc Natl Acad Sci U S A ; 115(12): 3072-3077, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29483242

RESUMO

The extent of increasing anthropogenic impacts on large marine vertebrates partly depends on the animals' movement patterns. Effective conservation requires identification of the key drivers of movement including intrinsic properties and extrinsic constraints associated with the dynamic nature of the environments the animals inhabit. However, the relative importance of intrinsic versus extrinsic factors remains elusive. We analyze a global dataset of ∼2.8 million locations from >2,600 tracked individuals across 50 marine vertebrates evolutionarily separated by millions of years and using different locomotion modes (fly, swim, walk/paddle). Strikingly, movement patterns show a remarkable convergence, being strongly conserved across species and independent of body length and mass, despite these traits ranging over 10 orders of magnitude among the species studied. This represents a fundamental difference between marine and terrestrial vertebrates not previously identified, likely linked to the reduced costs of locomotion in water. Movement patterns were primarily explained by the interaction between species-specific traits and the habitat(s) they move through, resulting in complex movement patterns when moving close to coasts compared with more predictable patterns when moving in open oceans. This distinct difference may be associated with greater complexity within coastal microhabitats, highlighting a critical role of preferred habitat in shaping marine vertebrate global movements. Efforts to develop understanding of the characteristics of vertebrate movement should consider the habitat(s) through which they move to identify how movement patterns will alter with forecasted severe ocean changes, such as reduced Arctic sea ice cover, sea level rise, and declining oxygen content.


Assuntos
Migração Animal , Bases de Dados Factuais , Oceanos e Mares , Vertebrados , Animais , Ecossistema
5.
West Indian Med J ; 64(4): 344-50, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26624585

RESUMO

OBJECTIVE: To characterize the frequency, incidence and severity of dengue fever in Suriname and to detect historic clusters of disease by integrating epidemiological data into a spatial visualization platform. METHODS: The frequency, incidence and severity of all reported dengue fever (DF) and dengue haemorrhagic fever (DHF) cases in Suriname from 2001 to 2012 were calculated and stratified by demographic factors. Using a geographic information systems (GIS) platform, we visualized the distribution of DF cases and used Moran's I to detect autocorrelation. Furthermore, a retrospective spatial Poisson probability model was used to identify local clusters of DF within Suriname. Local clusters were divided into neighborhoods and individual DF cases were mapped to the street level. RESULTS: In Suriname, cases of DF emerge in cyclical patterns (three to five years) with seasonal peaks following the short and the long rainy season. Chi-square analysis indicated a statistically significant (p < 0.05) difference between age group, ethnicity and district and the onset of DHF. The spatial analysis detected spatial autocorrelation and four statistically significant (p < 0.05) clusters were identified in the two most populated districts of Paramaribo and Wanica. CONCLUSION: In Suriname, identification of demographic and environmental risk factors that contribute to the development of DHF is essential to determine how preventive action can be more effectively allocated. The integration of epidemiological data into a GIS platform allowed for the identification of historic epidemiological clusters of dengue which will be used to guide environmental health studies in Suriname.

6.
Br J Biomed Sci ; 70(2): 67-74, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23888608

RESUMO

The QBC Star haematology system includes the QBC Star centrifugal analytical analyser and the QBC Star tube system. Together, they are capable of producing a haematology profile on venous or capillary whole blood. The aim of this study is to compare full blood count (FBC) including differential white cell count performance between the QBC Star analyser and a gold standard Sysmex XE-2100 haematology analyser. The FBC performance was evaluated according to the National Committee for Clinical Laboratory Standards (NCCLS) document H20-A. Imprecision, correlation and linearity studies all showed excellent results. Overall, the haemoglobin, haematocrit, white cell count (WCC) and platelet count parameters showed excellent correlation. Mean corpuscular haemoglobin concentration (MCHC) results showed poor comparability. The white cell differential parameters showed good correlation within certain clinically significant limits. Imprecision for haemoglobin, haematocrit, WCC, MCHC and platelet count was considered acceptable. The re-read function was found to be stable over the five-hour testing period under the authors' laboratory environmental conditions. The subjective assessment by biomedical scientist staff demonstrated that the system was user friendly, required little maintenance, and no user calibration was required. Staff considered the user manual to be excellent. Overall, the QBC Star appears to be an excellent point-of-care (POC) dry haematology analyser that delivers clinically significant nine-parameter complete blood count and will make a good POC analyser for use in field hospitals, research, screening programmes, GP surgeries as well as in emergency and intensive care units. It is a health and safety-friendly analyser considering the fact that it uses dry haematology reagents instead of the bulky wet reagents that are often associated with liquid biohazard waste.


Assuntos
Contagem de Células Sanguíneas/instrumentação , Hematologia/instrumentação , Sistemas Automatizados de Assistência Junto ao Leito , Contagem de Células Sanguíneas/normas , Calibragem , Desenho de Equipamento , Índices de Eritrócitos , Hematócrito/instrumentação , Hematócrito/normas , Hemoglobinas , Humanos , Contagem de Plaquetas/instrumentação , Contagem de Plaquetas/normas , Reprodutibilidade dos Testes
7.
Nat Genet ; 11(3): 248-56, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7581447

RESUMO

We have extended our analysis of the role of the long arm of the X chromosome (Xq28) in sexual orientation by DNA linkage analyses of two newly ascertained series of families that contained either two gay brothers or two lesbian sisters as well as heterosexual siblings. Linkage between the Xq28 markers and sexual orientation was detected for the gay male families but not for the lesbian families or for families that failed to meet defined inclusion criteria for the study of sex-linked sexual orientation. Our results corroborate the previously reported linkage between Xq28 and male homosexuality in selected kinships and suggest that this region contains a locus that influences individual variations in sexual orientation in men but not in women.


Assuntos
Ligação Genética , Comportamento Sexual , Cromossomo X , Sequência de Bases , Família , Feminino , Marcadores Genéticos , Homossexualidade Feminina/genética , Homossexualidade Masculina/genética , Humanos , Masculino , Dados de Sequência Molecular , Homologia de Sequência do Ácido Nucleico , Cromossomo Y
8.
Ann Trop Paediatr ; 31(1): 15-26, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21262106

RESUMO

OBJECTIVES: In young infants, early development of symptomatic HIV infection increases the risk of morbidity and mortality. A prospective study was conducted over a 1-year period in a region with a high burden of HIV in order to describe the clinical presentation of HIV infection in infants aged between 0 and 59 days on attendance at hospital and the factors associated with the need for urgent hospital management. METHODS: Sick young infants presenting to the King Edward VIII Hospital, Durban between February 2003 and January 2004 were enrolled. After systematic evaluation by a primary health worker, an experienced paediatrician determined the primary diagnosis and need for urgent hospital management. Comparisons of these assessments were stratified by HIV status. Children were classified as HIV-uninfected (HIV ELISA-negative), HIV-exposed-but-uninfected (HIV ELISA-positive and HIV RNA PCR-negative), HIV-infected (HIV ELISA-positive and HIV viral load >400 copies/ml). RESULTS: Of 925 infants enrolled, 652 (70·5%) had their HIV status determined: 70 (10·7%) were HIV-infected, 271 (41·6%) HIV-exposed-but-uninfected, and 311 (47·7%) HIV-uninfected. Factors associated with an increased probability of being HIV-infected included if the mother had children from more than one sexual partner, if the infant had had contact with a tuberculosis-infected person or if the HIV-infected mother and/or her exposed infant failed to receive nevirapine prophylaxis. Signs of severe illness were more frequently encountered in HIV-infected than in HIV-exposed-but-uninfected infants, including the prevalence of chest in-drawing (20·3% vs 8·8%, p = 0·004) and severe skin pustules (18·6% vs 8·6%, p = 0·01). Among infants requiring urgent hospital management, observed or reported feeding difficulties and severe skin pustules were more common in HIV-infected than uninfected infants. More HIV-infected infants (12·9%) required hospitalisation than those who were HIV-exposed-but-uninfected (7·7%) or uninfected (7·4%). Primary diagnoses of pneumonia, sepsis or oral thrush were more frequently seen in HIV-infected than exposed-but-uninfected or HIV-uninfected children. CONCLUSION: Early recognition and triaging of infants suspected of having HIV infection provides an opportunity for early diagnosis and treatment which could prevent the adverse impact of rapidly progressive HIV disease.


Assuntos
Infecções por HIV/complicações , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/uso terapêutico , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Lactente , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Masculino , Nevirapina/administração & dosagem , Nevirapina/uso terapêutico , África do Sul
9.
Int J Infect Dis ; 96: 54-60, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32304821

RESUMO

INTRODUCTION: Sepsis is the leading cause of infectious morbidity and mortality among hospitalized neonates. In high-resource pediatric and adult intensive care units, use of aqueous chlorhexidine (CHG) solution has been associated with reduced risk of bloodstream infections (BSI). OBJECTIVES: To assess the impact of bathing of neonates with 2% CHG on BSI, suspected sepsis, and mortality in a low-income country neonatal care unit. METHODS: We conducted a secondary analysis of data from the Sepsis Prevention in Neonates in Zambia (SPINZ) study, a prospective observational cohort study performed at a large public referral hospital in Lusaka, Zambia. The SPINZ study assessed the impact of an infection control bundle (consisting of alcohol hand rub, SMS hygiene reminders, enhanced environmental cleaning, and CHG baths for babies ≥1.5 kg) on sepsis, BSI, and all-cause mortality. Episodic shortages in study staffing resulted in some enrolled babies not receiving a CHG bath. Using Longitudinal Targeted Maximum Likelihood Estimation and Cox proportional hazards regression to adjust for observed confounding, we estimated the causal effect of receiving a CHG bath within the first 3 days of life on suspected sepsis, BSI, and death among inborn babies enrolled during the study implementation and intervention phases. RESULTS: The majority of inborn, enrolled babies ≥1.5 kg received a CHG bath within 3 days of NICU admission (864 of 1233, 70%). We found that CHG bathing reduced the hazard rate of BSI among inborn babies ≥1.5 kg by a factor of 0.58 (p = 0.10, 95% CI: 0.31, 1.11), corresponding to an absolute risk reduction of 9.6 percentage points within a week of admission (p = 0.002, 95% CI: 3.4-15.7 percentage points). We did not find a statistically significant effect of CHG bathing on culture-negative sepsis (p = 0.54) or death (p = 0.85). CONCLUSION: In our single center study, CHG bathing at admission was associated with a reduced risk of BSI due to a pathogenic organism after adjusting for potential confounding. Our results suggest that CHG may be an effective intervention for preventing neonatal sepsis in high-risk, low-income country settings.


Assuntos
Clorexidina , Controle de Infecções , Sepse/prevenção & controle , Banhos , Estudos de Coortes , Feminino , Mortalidade Hospitalar , Humanos , Higiene , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Estudos Prospectivos , Zâmbia
10.
Science ; 196(4286): 220-1, 1977 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-403605

RESUMO

Recombinants were constructed between various Escherichia coli plasmids and fragments of Drosophila melanogaster DNA. These recombinant plasmids are nonconjugative, but can be mobilized from one cell to another by conjugative sex factors. Of 47 recombinants studied, 46 were mobilized at approximately the same or slightly lower frequencies than the parental plasmids, whereas one was mobilized 1000 times less efficiently.


Assuntos
Conjugação Genética , DNA Bacteriano/metabolismo , DNA Recombinante/metabolismo , Drosophila melanogaster , Escherichia coli/metabolismo , Herança Extracromossômica , Plasmídeos , Drosophila melanogaster/metabolismo , Genes
11.
Science ; 235(4794): 1383-7, 1987 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-3103216

RESUMO

Mouse nuclear factors that bind to an upstream metal regulatory element of the mouse metallothionein-I gene have been identified by DNA footprinting and oligonucleotide band shift assays. The formation of complexes at this site can be activated 20- to 40-fold by the vitro addition of ionic cadmium. The activation reaction is rapid, reversible by a metal chelator, and may involve multiple proteins. These results suggest that the initial step in cadmium detoxification is an interaction between the metal and nuclear DNA-binding factors leading to an increase in metallothionein gene transcription. The ability to observe metal activation in vitro makes this a powerful system to study the biochemistry of eukaryotic gene regulation.


Assuntos
Genes Reguladores , Metalotioneína/genética , Transcrição Gênica , Animais , Sequência de Bases , Cádmio/farmacologia , Núcleo Celular/análise , DNA/genética , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Desoxirribonuclease I , Ácido Edético/farmacologia , Exodesoxirribonucleases , Camundongos , Oligonucleotídeos/genética , Fatores de Transcrição/metabolismo
12.
Science ; 228(4700): 685-90, 1985 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-3887570

RESUMO

The CUP1 gene of yeast encodes a small, metallothionein-like protein that binds to and is inducible by copper. A gene replacement experiment shows that this protein protects cells against copper poisoning but is dispensable for normal cellular growth and development throughout the yeast life cycle. The transcription of CUP1 is negatively autoregulated. This feedback mechanism, which is mediated through upstream control sequences, may play an important role in heavy metal homeostasis.


Assuntos
Metalotioneína/fisiologia , Saccharomyces cerevisiae/enzimologia , Proteínas de Transporte , Cobre/metabolismo , Sulfato de Cobre , Indução Enzimática , Genes Fúngicos , Metalotioneína/biossíntese , Metalotioneína/genética , Mutação , Óperon , Plasmídeos , RNA Mensageiro/biossíntese , Saccharomyces cerevisiae/genética
13.
Science ; 231(4740): 854-6, 1986 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-3080806

RESUMO

Expression of two monkey metallothioneins in yeast leads to complementation of both known functions of the endogenous yeast copperthionein gene, namely copper detoxification and autoregulation of transcription. The metallothionein-like proteins of higher and lower eukaryotes are therefore functionally analogous despite their dissimilar primary sequences.


Assuntos
Metalotioneína/fisiologia , Saccharomyces cerevisiae/fisiologia , Animais , Cobre/metabolismo , Regulação da Expressão Gênica , Teste de Complementação Genética , Haplorrinos , Metalotioneína/genética , Especificidade da Espécie , Relação Estrutura-Atividade , Transformação Genética
14.
Science ; 224(4653): 1104-6, 1984 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-6719135

RESUMO

Human metallothioneins are encoded by a complex multigene family. The chromosomal location of these genes has been determined by gel transfer hybridization analysis of the DNA from human-rodent cell hybrids. Chromosome 16 contains a cluster of metallothionein sequences, including two functional metallothionein I genes and a functional metallothionein II gene. The remaining sequences, including a processed pseudogene, are dispersed to at least four other autosomes. The absence of metallothionein sequences from the X chromosome indicates that Menkes' disease, an X-linked disorder of copper metabolism, affects metallothionein expression by a trans-acting mechanism.


Assuntos
Encefalopatias Metabólicas/genética , Mapeamento Cromossômico , Síndrome dos Cabelos Torcidos/genética , Metalotioneína/genética , Animais , Cromossomos Humanos 16-18 , Cobre/metabolismo , Cricetinae , Cricetulus , Humanos , Células Híbridas , Camundongos
15.
Science ; 261(5119): 321-7, 1993 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-8332896

RESUMO

The role of genetics in male sexual orientation was investigated by pedigree and linkage analyses on 114 families of homosexual men. Increased rates of same-sex orientation were found in the maternal uncles and male cousins of these subjects, but not in their fathers or paternal relatives, suggesting the possibility of sex-linked transmission in a portion of the population. DNA linkage analysis of a selected group of 40 families in which there were two gay brothers and no indication of nonmaternal transmission revealed a correlation between homosexual orientation and the inheritance of polymorphic markers on the X chromosome in approximately 64 percent of the sib-pairs tested. The linkage to markers on Xq28, the subtelomeric region of the long arm of the sex chromosome, had a multipoint lod score of 4.0 (P = 10(-5), indicating a statistical confidence level of more than 99 percent that at least one subtype of male sexual orientation is genetically influenced.


Assuntos
Genes , Ligação Genética , Homossexualidade , Cromossomo X , Feminino , Marcadores Genéticos , Genótipo , Humanos , Masculino , Linhagem , Fenótipo
16.
Science ; 196(4286): 210-2, 1977 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-322284

RESUMO

A plasmid containing cauliflower mosaic virus DNA can be faithfully cloned in Escherichia coli, but proved to be noninfective in test plants.


Assuntos
DNA Bacteriano/metabolismo , DNA Recombinante/metabolismo , DNA Viral/metabolismo , Vírus do Mosaico/metabolismo , Vírus de Plantas/metabolismo , Enzimas de Restrição do DNA , Escherichia coli/metabolismo , Peso Molecular , Vírus do Mosaico/crescimento & desenvolvimento , Plasmídeos , Replicação Viral
17.
Science ; 241(4874): 1813-5, 1988 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-3175622

RESUMO

Resistance to antineoplastic agents is the major obstacle to curative therapy of cancer. Tumor cell lines with acquired resistance to the antineoplastic agent cis-diamminedichloroplatinum(II) overexpressed metallothionein and demonstrated cross-resistance to alkylating agents such as chlorambucil and melphalan. Human carcinoma cells that maintained high levels of metallothionein because of chronic exposure to heavy metals were resistant to cis-diamminedichloroplatinum(II), melphalan, and chlorambucil. Furthermore, cells transfected with bovine papilloma virus expression vectors containing DNA encoding human metallothionein-IIA were resistant to cis-diamminedichloroplatinum(II), melphalan, and chlorambucil but not to 5-fluorouracil or vincristine. Thus, overexpression of metallothionein represents one mechanism of resistance to a subset of clinically important anticancer drugs.


Assuntos
Antineoplásicos , Resistência a Medicamentos , Metalotioneína/fisiologia , Animais , Northern Blotting , Células Cultivadas , Técnicas In Vitro , Camundongos
18.
Science ; 274(5292): 1527-31, 1996 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-8929413

RESUMO

Transporter-facilitated uptake of serotonin (5-hydroxytryptamine or 5-HT) has been implicated in anxiety in humans and animal models and is the site of action of widely used uptake-inhibiting antidepressant and antianxiety drugs. Human 5-HT transporter (5-HTT) gene transcription is modulated by a common polymorphism in its upstream regulatory region. The short variant of the polymorphism reduces the transcriptional efficiency of the 5-HTT gene promoter, resulting in decreased 5-HTT expression and 5-HT uptake in lymphoblasts. Association studies in two independent samples totaling 505 individuals revealed that the 5-HTT polymorphism accounts for 3 to 4 percent of total variation and 7 to 9 percent of inherited variance in anxiety-related personality traits in individuals as well as sibships.


Assuntos
Transtornos de Ansiedade/genética , Proteínas de Transporte/genética , Glicoproteínas de Membrana/genética , Proteínas de Membrana Transportadoras , Proteínas do Tecido Nervoso , Transtornos Neuróticos/genética , Polimorfismo Genético , Regiões Promotoras Genéticas , Serotonina/metabolismo , Adolescente , Adulto , Alelos , Linhagem Celular , Feminino , Marcadores Genéticos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Núcleo Familiar , Testes de Personalidade , Fenótipo , Proteínas da Membrana Plasmática de Transporte de Serotonina , Transfecção
19.
Bull World Health Organ ; 86(12): 929-38, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19142293

RESUMO

OBJECTIVE: To ascertain the microbiological consequences of WHO's recommendation for presumptive co-trimoxazole prophylaxis for infants with perinatal HIV exposure. METHODS: Using a longitudinal cohort design, we followed HIV-exposed and HIV-unexposed infants trimonthly for up to 18 months per infant. HIV-exposed infants received daily co-trimoxazole prophylaxis from 6 weeks to > or = 12 months of age. Using Streptococcus pneumoniae as our sentinel pathogen, we measured how co-trimoxazole altered nasopharyngeal colonization, pneumococcal resistance to antibiotics and serotype distribution as a function of co-trimoxazole exposure. FINDINGS: From 260 infants followed for 3096 patient-months, we detected pneumococci in 360/1394 (25.8%) samples. HIV-exposed infants were colonized more frequently than HIV-unexposed infants (risk ratio, RR: 1.4; 95% confidence interval, CI: 1.0-1.9, P = 0.04). Co-trimoxazole prophylaxis reduced colonization by ca 7% but increased the risk of colonization with co-trimoxazole-resistant pneumococci within 6 weeks of starting prophylaxis (RR: 3.2; 95% CI: 1.3-7.8, P = 0.04). Prophylaxis with co-trimoxazole led to a small but statistically significant increase of nasopharyngeal colonization with pneumococci not susceptible to clindamycin (RR: 1.6; 95% CI: 1.0-2.6, P = 0.04) but did not increase the risk of non-susceptibility to penicillin (RR: 1.1; 95% CI: 0.7-1.7), erythromycin (RR: 1.0; 95% CI: 0.6-1.7), tetracycline (RR: 0.9; 95% CI: 0.6-1.5) or chloramphenicol (RR: 0.8; 95% CI: 0.3-2.3). Co-trimoxazole prophylaxis did not cause the prevailing pneumococcal serotypes to differ from those that are targeted by the 7-valent conjugate pneumococcal vaccine (RR: 1.0; 95% CI: 0.7-1.6). CONCLUSION: Co-trimoxazole prophylaxis modestly suppresses pneumococcal colonization but accelerates infant acquisition of co-trimoxazole- and clindamycin-resistant pneumococci. Co-trimoxazole prophylaxis appears unlikely to compromise the future efficacy of conjugate vaccines.


Assuntos
Anti-Infecciosos/uso terapêutico , Antibioticoprofilaxia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Infecções Pneumocócicas/tratamento farmacológico , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Feminino , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Testes de Sensibilidade Microbiana , Infecções Pneumocócicas/epidemiologia , Estudos Soroepidemiológicos , Streptococcus pneumoniae/efeitos dos fármacos , Zâmbia/epidemiologia
20.
Trop Med Int Health ; 13(1): 99-107, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18291008

RESUMO

OBJECTIVE: To describe the quality of outpatient paediatric malaria case-management approximately 4-6 months after artemether-lumefantrine (AL) replaced sulfadoxine-pyrimethamine (SP) as the nationally recommended first-line therapy in Kenya. METHODS: Cross-sectional survey at all government facilities in four Kenyan districts. Main outcome measures were health facility and health worker readiness to implement AL policy; quality of antimalarial prescribing, counselling and drug dispensing in comparison with national guidelines; and factors influencing AL prescribing for treatment of uncomplicated malaria in under-fives. RESULTS: We evaluated 193 facilities, 227 health workers and 1533 sick-child consultations. Health facility and health worker readiness was variable: 89% of facilities stocked AL, 55% of health workers had access to guidelines, 46% received in-service training on AL and only 1% of facilities had AL wall charts. Of 940 children who needed AL treatment, AL was prescribed for 26%, amodiaquine for 39%, SP for 4%, various other antimalarials for 8% and 23% of children left the facility without any antimalarial prescribed. When AL was prescribed, 92% of children were prescribed correct weight-specific dose. AL dispensing and counselling tasks were variably performed. Higher health worker's cadre, in-service training including AL use, positive malaria test, main complaint of fever and high temperature were associated with better prescribing. CONCLUSIONS: Changes in clinical practices at the point of care might take longer than anticipated. Delivery of successful interventions and their scaling up to increase coverage are important during this process; however, this should be accompanied by rigorous research evaluations, corrective actions on existing interventions and testing cost-effectiveness of novel interventions capable of improving and maintaining health worker performance and health systems to deliver artemisinin-based combination therapy in Africa.


Assuntos
Assistência Ambulatorial , Artemisininas/uso terapêutico , Fluorenos/uso terapêutico , Política de Saúde , Malária/tratamento farmacológico , Sesquiterpenos/uso terapêutico , Antimaláricos/administração & dosagem , Antimaláricos/uso terapêutico , Combinação Arteméter e Lumefantrina , Artemisininas/administração & dosagem , Pré-Escolar , Estudos Transversais , Combinação de Medicamentos , Etanolaminas , Fluorenos/administração & dosagem , Fidelidade a Diretrizes , Pessoal de Saúde , Humanos , Lactente , Recém-Nascido , Entrevistas como Assunto , Quênia , Padrões de Prática Médica , Avaliação de Programas e Projetos de Saúde , Sesquiterpenos/administração & dosagem
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