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161.
The objective of the present experiment was to determine the implications of prenatal undernutrition on the behaviour of juvenile lambs. Dams of one group (C) were fed 100% of the recommended requirements throughout pregnancy, while those of two other groups were fed 50% of the control nutrient allowance during the first 30 days of pregnancy (R1) or 50% of the control nutrient allowance from days 31–100 of pregnancy (R2). Between 2 and 5 months old, behaviour of lambs was tested by the implementation of 2 types of test: isolation and novelty. There were no statistical differences between lamb treatments in escape behaviour and heart rates during isolation test, or the latency to approach a novel or a familiar object in the novelty test in tests conducted at 2, 3, 4 and 5 months of age.Male lambs showed a tendency of turning to the right-hand side of the test pen, irrespective of treatment group, between the age of 2 and 5 months old. A greater proportion of C compared to R1 males turned right at the age of 2 and 5 months old (P < 0.05). Significant differences concerning laterality were found also between C and R1 female lambs at the age of 2 and 4 months old (P < 0.001), between C and R2 male lambs at the age of 2 months old (P < 0.05), between C and R2 female lambs at the age of 4 and 5 months old (P < 0.01), between R1 and R2 male lambs at the age of 2 and 5 months old (P < 0.05) and between R1 and R2 female lambs at the age of 2 months old (P < 0.001).It is concluded that prenatal undernutrition during different periods of pregnancy had no effect on fear-related behaviour, but effect on laterality at the early stages of lamb age between 2 and 5 months old.  相似文献   
162.
Polyamine oxidase (PAO) catalyzes the oxidative catabolism of spermidine and spermine, generating hydrogen peroxide. In wild-type tobacco (Nicotiana tabacum ‘Xanthi’) plants, infection by the compatible pathogen Pseudomonas syringae pv tabaci resulted in increased PAO gene and corresponding PAO enzyme activities; polyamine homeostasis was maintained by induction of the arginine decarboxylase pathway and spermine was excreted into the apoplast, where it was oxidized by the enhanced apoplastic PAO, resulting in higher hydrogen peroxide accumulation. Moreover, plants overexpressing PAO showed preinduced disease tolerance against the biotrophic bacterium P. syringae pv tabaci and the hemibiotrophic oomycete Phytophthora parasitica var nicotianae but not against the Cucumber mosaic virus. Furthermore, in transgenic PAO-overexpressing plants, systemic acquired resistance marker genes as well as a pronounced increase in the cell wall-based defense were found before inoculation. These results reveal that PAO is a nodal point in a specific apoplast-localized plant-pathogen interaction, which also signals parallel defense responses, thus preventing pathogen colonization. This strategy presents a novel approach for producing transgenic plants resistant to a broad spectrum of plant pathogens.  相似文献   
163.

Background

Fractures have largely been assessed by their impact on quality of life or health care costs. We conducted this study to evaluate the relation between fractures and mortality.

Methods

A total of 7753 randomly selected people (2187 men and 5566 women) aged 50 years and older from across Canada participated in a 5-year observational cohort study. Incident fractures were identified on the basis of validated self-report and were classified by type (vertebral, pelvic, forearm or wrist, rib, hip and “other”). We subdivided fracture groups by the year in which the fracture occurred during follow-up; those occurring in the fourth and fifth years were grouped together. We examined the relation between the time of the incident fracture and death.

Results

Compared with participants who had no fracture during follow-up, those who had a vertebral fracture in the second year were at increased risk of death (adjusted hazard ratio [HR] 2.7, 95% confidence interval [CI] 1.1–6.6); also at risk were those who had a hip fracture during the first year (adjusted HR 3.2, 95% CI 1.4–7.4). Among women, the risk of death was increased for those with a vertebral fracture during the first year (adjusted HR 3.7, 95% CI 1.1–12.8) or the second year of follow-up (adjusted HR 3.2, 95% CI 1.2–8.1). The risk of death was also increased among women with hip fracture during the first year of follow-up (adjusted HR 3.0, 95% CI 1.0–8.7).

Interpretation

Vertebral and hip fractures are associated with an increased risk of death. Interventions that reduce the incidence of these fractures need to be implemented to improve survival.Osteoporosis-related fractures are a major health concern, affecting a growing number of individuals worldwide. The burden of fracture has largely been assessed by the impact on health-related quality of life and health care costs.1,2 Fractures can also be associated with death. However, trials that have examined the relation between fractures and mortality have had limitations that may influence their results and the generalizability of the studies, including small samples,3,4 the examination of only 1 type of fracture,410 the inclusion of only women,8,11 the enrolment of participants from specific areas (i.e., hospitals or certain geographic regions),3,4,7,8,10,12 the nonrandom selection of participants311 and the lack of statistical adjustment for confounding factors that may influence mortality.3,57,12We evaluated the relation between incident fractures and mortality over a 5-year period in a cohort of men and women 50 years of age and older. In addition, we examined whether other characteristics of participants were risk factors for death.  相似文献   
164.
Implantable Cardioverter Defibrillator (ICD) implantation is the only established therapy for primary or secondary prevention of sudden cardiac death in patients with Hypertrophic Cardiomyopathy (HCM). Ineffectiveness of shock therapy for the termination of potentially fatal ventricular arrhythmias in ICD recipients is rare in the presence of appropriate arrhythmia detection by the device. We report the case of a 48-year-old woman with HCM and a single chamber ICD, who received five inefficient high-energy (35 Joules) shocks for the termination of an appropriately detected episode of Ventricular Tachycardia (VT). The episode was safely terminated with a subsequent application of Antitachycardia Pacing (ATP) by the device. At the following ICD control, an acceptable defibrillation threshold was detected.  相似文献   
165.
166.
We have designed and synthesized a series of novel molecules having a residue of a classical NSAID and an antioxidant moiety, both attached through amide bonds to a known nootropic structure, an L-proline, trans-4-hydroxy-L-proline or DL-pipecolinic acid residue. The compounds were found to retain anti-inflammatory and antioxidant activities, to acquire hypocholesterolemic action, and to possess a greatly reduced gastrointestinal toxicity. The novel molecules could find useful applications, among others, in slowing the progression or delaying the onset of neurodegenerative diseases.  相似文献   
167.
CYP1A2, a principal catalyst for metabolism of various therapeutic drugs and carcinogens, among others, is in part regulated by the stress response. This study was designed to assess whether catecholamines and in particular adrenergic receptor-dependent pathways, modulate benzo(alpha)pyrene (B(alpha)P)-induced hepatic CYP1A2. To distinguish between the role of central and peripheral catecholamines in the regulation of CYP1A2 induction, the effect of central and peripheral catecholamine depletion using reserpine was compared to that of peripheral catecholamine depletion using guanethidine. The effects of peripheral adrenaline and L-DOPA administration were also assessed. The results suggest that alterations in central catecholamines modulate 7-methoxyresorufin O-demethylase activity (MROD), CYP1A2 mRNA and protein levels in the B(alpha)P-induced state. In particular, central catecholamine depletion, dexmedetomidine-induced inhibition of noradrenaline release and blockade of alpha(1)-adrenoceptors with prazosin, up-regulated CYP1A2 expression. Phenylephrine and dexmedetomidine-induced up-regulation may be mediated, in part, via peripheral alpha(1)- and alpha(2)-adrenoceptors, respectively. On the other hand, the L-DOPA-induced increase in central dopaminergic activity was not followed by any change in the up-regulation of CYP1A2 expression by B(alpha)P. Central noradrenergic systems appeared to counteract up-regulating factors, most likely via alpha(1)- and alpha(2)-adrenoceptors. In contrast, peripheral alpha- and beta-adrenoceptor-related signaling pathways are linked to up-regulating processes. The findings suggest that drugs that bind to adrenoceptors or affect central noradrenergic neurotransmission, as well as factors that challenge the adrenoceptor-linked signaling pathways may deregulate CYP1A2 induction. This, in turn, may result in drug-therapy and drug-toxicity complications.  相似文献   
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