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1.
J Infect Dis ; 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39013016

RESUMEN

BACKGROUND: Pneumococcal carriage in children has been extensively studied, but carriage in healthy adults and its relationship to invasive pneumococcal disease (IPD) is less understood. METHODS: Nasal wash samples from adults without close contact with young children (Liverpool, UK), 2011-2019, were cultured, and culture-negative samples tested by PCR. Pneumococcal carriage in adults 18-44 years was compared with carriage among PCV-vaccinated children 13-48 months (nasopharyngeal swabs, Thames Valley, UK) and IPD data for England for the same ages for 2014-2019. Age-group specific serotype invasiveness was calculated and used with national IPD data to estimate carriage serotype distributions for adults aged 65+ years. RESULTS: In total 98 isolates (97 carriers) were identified from 1,631 adults aged 18+ years (age and sex standardized carriage prevalence 6.4%), with only three identified solely by PCR. Despite different carriage and IPD serotype distributions between adults and children, serotype invasiveness was highly correlated (R=0.9). Serotypes 3, 37 and 8 represented a higher proportion of adult carriage than expected from direct low-level transmission from children to adults. The predicted carriage serotype distributions for 65+ years aligned more closely with the carriage serotype distribution for young adults than young children. CONCLUSIONS: The nasal wash technique is highly sensitive; additional benefit of PCR is limited. Comparison of carriage serotype distributions suggests some serotypes may be circulating preferentially within these specific young adults. Our data suggest that for some serotypes carried by adults 65+ years, other adults may be an important reservoir for transmission. Age groups such as older children should also be considered.

2.
J Membr Biol ; 227(3): 151-8, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19132435

RESUMEN

Our understanding of vascular endothelial cell physiology is based on studies of endothelial cells cultured from various vascular beds of different species for varying periods of time. Systematic analysis of the properties of endothelial cells from different parts of the vasculature is lacking. Here, we compare Ca(2+) homeostasis in primary cultures of endothelial cells from human internal mammary artery and saphenous vein and how this is modified by hypoxia, an inevitable consequence of bypass grafting (2.5% O(2), 24 h). Basal [Ca(2+)]( i ) and store depletion-mediated Ca(2+) entry were significantly different between the two cell types, yet agonist (ATP)-mediated mobilization from endoplasmic reticulum stores was similar. Hypoxia potentiated agonist-evoked responses in arterial, but not venous, cells but augmented store depletion-mediated Ca(2+) entry only in venous cells. Clearly, Ca(2+) signaling and its remodeling by hypoxia are strikingly different in arterial vs. venous endothelial cells. Our data have important implications for the interpretation of data obtained from endothelial cells of varying sources.


Asunto(s)
Señalización del Calcio/fisiología , Hipoxia de la Célula/fisiología , Células Endoteliales/metabolismo , Calcio/metabolismo , Células Cultivadas , Humanos , Técnicas de Placa-Clamp
3.
Rev. biol. trop ; 56(3): 1371-1380, sep. 2008. ilus
Artículo en Inglés | LILACS | ID: lil-637869

RESUMEN

The structural and ultrastructural features of gonads from endemic Mexican fish have received scarce attention. This study describes the histological and ultrastructural characteristics of oocyte from Chirostoma humboldtianum. The ovary is asynchronic, and as such, most phases of oocyte development are found in the same ovary. The complete process of oogenesis was divided in five stages: oogonium and folliculogenesis, primary growth, cortical alveoli and lipid inclusions, vitellogenesis, and maturation. The presence of big filaments, which appear at the end of primary growth, induces some common follicular adaptation. During primary growth, abundant ribosomes, the rough endoplasmic reticulum, and mitochondria are grouped in the cytoplasm. At the end of this stage, the Z1 layer of the chorion is developed, while microvilli start to be evident. In the cortical alveoli and lipid droplets phase, intense PAS positive vesicles, some of them containing nucleoid material, are observed in the peripheral cytoplasm and the lipid droplets take a more central position. In vitellogenesis, the proteic yolk accumulates in a centripetal way while the chorion is completely formed. During maturation, the germinal vesicle migrates to the animal pole, meiosis is restored, and there is nuclear breakdown. The oocyte increases its size and holds some oil droplets and a big fluid mass of yolk. On the outside, filaments completely surround the oocyte. Rev. Biol. Trop. 56 (3): 1371-1380. Epub 2008 September 30.


Asunto(s)
Animales , Femenino , Peces/anatomía & histología , Oocitos/ultraestructura , Oogénesis/fisiología , Ovario/ultraestructura , Peces/fisiología , México , Oocitos/fisiología , Ovario/fisiología
4.
Rev Biol Trop ; 56(3): 1371-80, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19419050

RESUMEN

The structural and ultrastructural features of gonads from endemic Mexican fish have received scarce attention. This study describes the histological and ultrastructural characteristics of oocyte from Chirostoma humboldtianum. The ovary is asynchronic, and as such, most phases of oocyte development are found in the same ovary. The complete process of oogenesis was divided in five stages: oogonium and folliculogenesis, primary growth, cortical alveoli and lipid inclusions, vitellogenesis, and maturation. The presence of big filaments, which appear at the end of primary growth, induces some common follicular adaptation. During primary growth, abundant ribosomes, the rough endoplasmic reticulum, and mitochondria are grouped in the cytoplasm. At the end of this stage, the Z1 layer of the chorion is developed, while microvilli start to be evident. In the cortical alveoli and lipid droplets phase, intense PAS positive vesicles, some of them containing nucleoid material, are observed in the peripheral cytoplasm and the lipid droplets take a more central position. In vitellogenesis, the proteic yolk accumulates in a centripetal way while the chorion is completely formed. During maturation, the germinal vesicle migrates to the animal pole, meiosis is restored, and there is nuclear breakdown. The oocyte increases its size and holds some oil droplets and a big fluid mass of yolk. On the outside, filaments completely surround the oocyte.


Asunto(s)
Peces/anatomía & histología , Oocitos/ultraestructura , Oogénesis/fisiología , Ovario/ultraestructura , Animales , Femenino , Peces/fisiología , México , Oocitos/fisiología , Ovario/fisiología
6.
Aust J Public Health ; 16(2): 158-61, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1391157

RESUMEN

A case-control study examining the risk factors for sudden infant death syndrome (SIDS) in New Zealand identified three risk factors that are potentially amenable to modification: prone sleeping position of the infant, maternal smoking and lack of breastfeeding. In total these three risk factors may account for 79 per cent of deaths from SIDS in New Zealand. We describe the planning and implementation of the cot death prevention program, which has involved a wide range of groups and different strategies. The outcome of the prevention program is being evaluated.


Asunto(s)
Desarrollo de Programa , Muerte Súbita del Lactante/prevención & control , Promoción de la Salud , Humanos , Lactante , Recién Nacido , Nueva Zelanda/epidemiología , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Muerte Súbita del Lactante/epidemiología
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