To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Chronic hypoxia during gestation induces greater occurrence of perinatal complications such as intrauterine growth restriction, fetal hypoxia, newborn asphyxia, and respiratory distress, among others. This condition may also cause a failure in the transition of the fetal to neonatal circulation, inducing pulmonary arterial hypertension of the neonate (PAHN), a syndrome that involves pulmonary vascular dysfunction, increased vasoconstrictor tone and pathological remodeling. As this syndrome has a relatively low prevalence in lowlands (~7 per 1000 live births) and very little is known about its prevalence and clinical evolution in highlands (above 2500 meters), our understanding is very limited. Therefore, studies on appropriate animal models have been crucial to comprehend the mechanisms underlying this pathology. Considering the strengths and weaknesses of any animal model of human disease is fundamental to achieve an effective and meaningful translation to clinical practice. The sheep model has been used to study the normal and abnormal cardiovascular development of the fetus and the neonate for almost a century. The aim of this review is to highlight the advances in our knowledge on the programming of cardiopulmonary function with the use of high-altitude newborn sheep as a translational model of PAHN.
Prenatal glucocorticoid overexposure has been shown to programme adult cardiovascular function in a range of species, but much less is known about the long-term effects of neonatal glucocorticoid overexposure. In horses, prenatal maturation of the hypothalamus–pituitary–adrenal axis and the normal prepartum surge in fetal cortisol occur late in gestation compared to other precocious species. Cortisol levels continue to rise in the hours after birth of full-term foals and increase further in the subsequent days in premature, dysmature and maladapted foals. Thus, this study examined the adult cardiovascular consequences of neonatal cortisol overexposure induced by adrenocorticotropic hormone administration to full-term male and female pony foals. After catheterisation at 2–3 years of age, basal arterial blood pressures (BP) and heart rate were measured together with the responses to phenylephrine (PE) and sodium nitroprusside (SNP). These data were used to assess cardiac baroreflex sensitivity. Neonatal cortisol overexposure reduced both the pressor and bradycardic responses to PE in the young adult males, but not females. It also enhanced the initial hypotensive response to SNP, slowed recovery of BP after infusion and reduced the gain of the cardiac baroreflex in the females, but not males. Basal diastolic pressure and cardiac baroreflex sensitivity also differed with sex, irrespective of neonatal treatment. The results show that there is a window of susceptibility for glucocorticoid programming during the immediate neonatal period that alters cardiovascular function in young adult horses in a sex-linked manner.
The Endangered Cuvier's gazelle Gazella cuvieri is an endemic ungulate of north-western Africa. Information on the species has been based primarily on non-systematic surveys, and the corresponding status estimates are of unknown quality. We evaluate the effectiveness and efficiency of two field methods for systematic surveys of populations of Cuvier's gazelle in arid environments: distance sampling (based on sightings) and sampling indirect sign (tracks and scats). The work was carried out in the north-western Sahara Desert, in Morocco, where what is possibly the largest population of Cuvier's gazelle persists. A logistically viable survey was conducted over a total area of c. 20.000 km2 in 10 expeditions during 2011–2014. A total of 67 sites were surveyed, with 194 walking surveys (2,169 km in total). Gazelle signs were detected at 50 sites, and gazelles were sighted at 21 sites (61 individuals). We found a relationship between sightings and abundance indices based on indirect sign, which could be useful for population monitoring or ecological studies. Additionally, the data could be used in occupancy modelling. Density estimates based on distance sampling required considerable effort; however, it is possible to survey large areas during relatively short campaigns, and this proved to be the most useful approach to obtain data on the demographic structure of the population.
High blood pressure (BP) has been ranked as the most important risk factor worldwide regarding attributable deaths. Dietary habits are major determinants of BP. Among them, frequent intake of low-fat dairy products may protect against hypertension. Our aim was to assess the relationship between low-fat dairy product intake and BP levels and their changes after 12-month follow-up in a cohort of asymptomatic older persons at high cardiovascular risk recruited into a large-scale trial assessing the effects of Mediterranean diets on cardiovascular outcomes. Data from 2290 participants, including 1845 with hypertension, were available for analyses. Dairy products were not a specific part of the intervention; thus, data were analysed as an observational cohort. Dietary information was collected with validated semi-quantitative FFQ and trained personnel measured BP. To assess BP changes, we undertook cross-sectional analyses at baseline and at the end of follow-up and longitudinal analyses. A statistically significant inverse association between low-fat dairy product intake and systolic BP was observed for the 12-month longitudinal analysis. In the longitudinal analysis, the adjusted systolic and diastolic BP were significantly lower in the highest quintile of low-fat dairy product intake ( − 4·2 (95% CI − 6·9, − 1·4) and − 1·8 (95% CI − 3·2, − 0·4) mmHg respectively), whereas the point estimates for the difference in diastolic BP indicated a modest non-significant inverse association. Intake of low-fat dairy products was inversely associated with BP in an older population at high cardiovascular risk, suggesting a possible protective effect against hypertension.
To determine the effect of under-nutrition during suckling in adults, at delivery female Sprague Dawley rats were allowed to lactate litters of either eight (controls) or sixteen pups each (large litter, LL). The amount of milk taken by LL pups was less than the controls and the concentration of triacylglycerols (TG) in the milk of the former was lower. The increase of both body weight and length in LL was lower than in the controls during suckling. At weaning, pups were allowed to eat ad libitum a standard diet and whereas at 20 months female body weight did not differ between LL and control rats, LL males weighed less than controls. Plasma NEFA were lower in male LL than in controls at 10 months, leptin at 10 and 16 months and TG and VLDL-TG at 20 months, with no differences in females. When 20 months old, lumbar and epididymal adipose tissue weights were lower in male LL than in controls, but not in females. The increase in plasma insulin after oral glucose load was lower in LL than in controls, both in males and females at 4 and 16 months, and only in males at 10 months, whereas the change in plasma glucose remained constant between the groups. Results indicate that both the pancreatic β-cell function and insulin sensitivity and adipose tissue metabolism are independently programmed as a consequence of under-nutrition during suckling, the effect being more manifest for males than for females.
Cognitive evaluation in developing countries is a difficult
undertaking due to low levels of schooling and particularly the
illiteracy still frequent in the elderly. This study was part of the
epidemiologic evaluation of dementia in Catanduva, Brazil, and had the
objective of comparing the performance of illiterate and literate
nondemented elderly individuals in 2 tests of long-term
memory—the delayed recall of a word list from the CERAD and the
delayed recall of common objects presented as simple drawings from the
Brief Cognitive Screening Battery (BCSB). Fifty-one elderly subjects
(23 illiterates) were evaluated, and the performance of the illiterates
and literates differed in the CERAD memory test, but not in the BCSB
memory test. This test may be more suitable for the assessment of
long-term memory in populations with a high frequency of illiterates,
and therefore might prove to be a useful screening tool for the
diagnosis of dementia. (JINS, 2004, 10,
The foraging behaviour of capybaras (Hydrochaeris hydrochaeris) was assessed in relation to habitat and season in a flooded savanna of Venezuela from February (dry season) 1993 to June (rainy season) 1994. Direct observations were carried out to record group movements and foraging activities of individual capybaras when feeding on specific plant species. The time devoted to feeding upon some species was recorded in relation to total foraging time (feeding + searching). Capybaras spent similar times feeding on reed (Eleocharis interstincta; Cyperaceae) and Paratheria prostrata (Poaceae) patches during the dry season though plant quality was different. During the rainy season, reeds were almost ignored by the animals which fed mainly on Hymenachne amplexicaulis, a grass with a significantly higher content of energy and protein. Capybaras fed for longer time during the dry season but more selectively during the rainy season. Capybaras were the dominant grazers in this flood savanna as inferred from the comparative effects they produced in the height, biomass and quality of the pasture in relation to those effects produced by other vertebrate herbivores, namely, cattle, feral horses and asses.
Email your librarian or administrator to recommend adding this to your organisation's collection.