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101.
Emilins are a family of extracellular matrix proteins with common structural organization and containing a characteristic N-terminal cysteine-rich domain. The prototype of this family, Emilin-1, is found in human and murine organs in association with elastic fibers, and other emilins were recently isolated in mammals. To gain insight into these proteins in lower vertebrates, we investigated the expression of emilins in the fish Danio rerio. Using sequence similarity tools, we identified eight members of this family in zebrafish. Each emilin gene has two paralogs in zebrafish, showing conserved structure with the human ortholog. In situ hybridization revealed that expression of zebrafish emilin genes is regulated in a spatiotemporal manner during embryonic development, with overlapping and site-specific patterns mostly including mesenchymal structures. Expression of certain emilin genes in peculiar areas, such as the central nervous system or the posterior notochord, suggests that they may play a role in key morphogenetic processes.  相似文献   
102.
The role of blue cones as well as the pathways they supply (collectively called the "blue mechanism") is evaluated by comparing ordinary wavelength discrimination functions with those obtained using two methods designed to inhibit the blue mechanism selectively. These methods use a just-noticeable-border criterion (JNB), instead of the usual one of just-noticeable-difference, and a yellow preadapting field to induce transient tritanopia. Without transient tritanopia, the data obtained using the just-noticeable-border criterion reveal a small contribution of the blue mechanism to wavelength discrimination. Transient tritanopia, with JNB, produces an additional selective loss of wavelength discrimination in a spectral region flanking 460 nm, which yields a function resembling those for tritanopes previously examined.  相似文献   
103.
Normal cerebrospinal fluid pressure in the newborn   总被引:2,自引:0,他引:2  
Lumbar CSF pressure (CSFP) was measured on 61 occasions, in 49 babies undergoing lumbar puncture as part of a septic screen, by means of Gaeltec pressure transducers. In normal circumstances, intracranial pressure (ICP) has the same value. Measurements were made when the baby was horizontal and quiet, with the head deflexed. For acceptance of the measurement, it was essential for the CSF to be clear and to show pressure pulses with respiration, heartbeat and jugular occlusion. The mean CSFP and standard deviation were 2.8 +/- 1.4 mm Hg (3.8 +/- 1.9 cm water), with a normal range of 0 to 5.7 mm Hg (0 to 7.6 cm water). This value is similar to previous reports of CSFP measured invasively in infants, but is much lower than the "ICP" established noninvasively. No relationship was found between birthweight, gestational age, current weight, postmenstrual age, or postnatal age and CSFP.  相似文献   
104.
Background: A major problem of aging is the disruption of metabolic homeostasis. This is particularly relevant in the brain where it provokes neurodegeneration. Caloric restriction is a physiologic intervention known to delay the deleterious consequences of aging in several species ranging from yeast to mammals. To date, most studies on experimental models have started this dietary intervention from weaning, which is very difficult to be translated to human beings. Here, we study the effects of a more realistic dietary regimen in rats, starting at an advanced age and lasting for six months. Methods: we analyzed in the cortex and hippocampus, the proteins involved in the energetic balance of the cells, cholesterol metabolism, oxidative stress response, inflammation, synaptic impairment, and brain trophism. Results: our results suggest that caloric restriction in late life can revert only some age-related changes studied here.  相似文献   
105.
106.
Vitamin D has been claimed to be effective in the response to infections, including the respiratory syndrome coronavirus 2 (SARS-CoV-2). It is supposed that lockdown measures and fear of SARS-CoV-2 infection might reduce vitamin D levels through the modification of lifestyle. However, very few data exist on the association between lockdown measures and vitamin D status in humans. For this cross-sectional comparative study, adolescents (n = 298) aged 18 to 19 years were enrolled during the compulsory military fitness-for-duty evaluation between July and December 2020 in Southern Switzerland. Beyond anthropometric measurements, participants filled in a structured questionnaire about their lifestyle and a blood specimen was sampled for the determination of total 25-hydroxy-vitamin D. The obtained data were compared with those of 437 adolescents enrolled at the military fitness-for-duty evaluation during the same period of the year in the context of the CENERI study (2014–2016). The anthropometric measures were similar between the two study groups. The levels of vitamin D were also comparable (77 (64–91) vs. 74 (60–92) nmol/L, p = 0.50; median and interquartile range). A total of 38 (13%) and 43 (9.8%) subjects presented insufficient (<50 nmol/L) levels of vitamin D (p = 0.42) during the current pandemic and in the CENERI study, respectively. These data do not support the hypothesis that during the SARS-CoV-2 pandemic, late adolescents are at higher risk of vitamin insufficiency.  相似文献   
107.
Time-restricted feeding (TRF) is becoming a popular way of eating in physically active populations, despite a lack of research on metabolic and performance outcomes as they relate to the timing of food consumption in relation to the time of exercise. The purpose of this study was to determine if the timing of feeding/fasting after exercise training differently affects muscle metabolic flexibility and response to an acute bout of exercise. Male C57BL/6 mice were randomized to one of three groups for 8 weeks. The control had ad libitum access to food before and after exercise training. TRF-immediate had immediate access to food for 6 h following exercise training and the TRF-delayed group had access to food 5-h post exercise for 6 h. The timing of fasting did not impact performance in a run to fatigue despite TRF groups having lower hindlimb muscle mass. TRF-delayed had lower levels of muscle HSL mRNA expression and lower levels of PGC-1α expression but displayed no changes in electron transport chain enzymes. These results suggest that in young populations consuming a healthy diet and exercising, the timing of fasting may not substantially impact metabolic flexibility and running performance.  相似文献   
108.
PurposeExploring the impact of the COVID-19 pandemic on young people’s mental health is an increasing priority. Studies to date are largely surveys and lack meaningful involvement from service users in their design, planning, and delivery. The study aimed to examine the mental health status and coping strategies of young people during the first UK COVID-19 lockdown using coproduction methodology.MethodsThe mental health status of young people (aged 16–24) in April 2020 was established utilizing a sequential explanatory coproduced mixed methods design. Factors associated with poor mental health status, including coping strategies, were also examined using an online survey and semi-structured interviews.ResultsSince the lockdown, 30.3% had poor mental health, and 10.8% had self-harmed. Young people identifying as Black/Black-British ethnicity had the highest increased odds of experiencing poor mental health (odds ratio [OR] 3.688, 95% CI .54–25.40). Behavioral disengagement (OR 1.462, 95% CI 1.22–1.76), self-blame (OR 1.307 95% CI 1.10–1.55), and substance use (OR 1.211 95% CI 1.02–1.44) coping strategies, negative affect (OR 1.109, 95% CI 1.07–1.15), sleep problems (OR .915 95% CI .88–.95) and conscientiousness personality trait (OR .819 95% CI .69–.98) were significantly associated with poor mental health. Three qualitative themes were identified: (1) pre-existing/developed helpful coping strategies employed, (2) mental health difficulties worsened, and (3) mental health and nonmental health support needed during and after lockdown.ConclusionPoor mental health is associated with dysfunctional coping strategies. Innovative coping strategies can help other young people cope during and after lockdowns, with digital and school promotion and application.  相似文献   
109.
We report 3 cases of Puumala virus infection in a family in Switzerland in January 2019. Clinical manifestations of the infection ranged from mild influenza-like illness to fatal disease. This cluster illustrates the wide range of clinical manifestations of Old World hantavirus infections and the challenge of diagnosing travel-related hemorrhagic fevers.  相似文献   
110.
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