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91.
92.
In the period before and after parturition, i.e., in pregnancy and lactation, a variety of neuroendocrine alterations occur that are accompanied by marked behavioral changes, including emotional responsiveness to external challenging situations. On the one hand, activation of neuroendocrine systems (oxytocin, prolactin) ensures reproduction-related physiological processes, but in a synergistic manner also ensures accompanying behaviors necessary for the survival of the offspring. On the other hand, there is a dramatic reduction in the responsiveness of neuroendocrine systems to stimuli not relevant for reproduction, such as the hypothalamo-pituitary-adrenal (HPA) axis responses to physical or emotional stimuli in both pregnant and lactating rats. With CRH being the main regulator of the HPA axis, downregulation of the brain CRH system may result in various behavioral, in particular emotional, adaptations of the maternal organisms, including changes in anxiety-related behavior. In support of this, the lactating rat becomes less emotionally responsive to novel situations, demonstrating reduced anxiety, and shows a higher degree of aggressive behavior in the test for agonistic behavior as well as in the maternal defense test. These changes in emotionality are independent of the innate (pre-lactation) level of anxiety and are seen in both rats bred for high as well as low levels of anxiety. Both brain oxytocin and prolactin, highly activated at this time, play a significant role in these behavioral and possibly also neuroendocrine adaptations in the peripartum period.  相似文献   
93.
Guanidinoacetate methyltransferase deficiency, which so far has been exclusively detected in children, was diagnosed in a 26-year-old man. The full-blown spectrum of clinical symptoms already had been present since infancy without progression of symptoms during adolescence. Cranial magnetic resonance imaging showed normal findings. Ophthalmological examination showed no retinal changes. Besides creatine deficiency in the brain, a distinct lack of phosphocreatine in skeletal muscle was proved by (31)P magnetic resonance spectroscopy. Creatine substitution combined with a guanidinoacetate-lowering diet introduced first at the age of 26 years was shown to be effective by an impressive improvement of epileptic seizures, mental capabilities, and general behavior and by normalization of the (31)P spectrum in the skeletal muscle.  相似文献   
94.
BACKGROUND: The purpose of the study was to examine whether penicillin-susceptible and nonsusceptible strains of Streptococcus pneumoniae exhibited different pharmacodynamic responses to benzylpenicillin. METHODS: The postantibiotic effects (PAEs) and the postantibiotic sub-MIC effects (PA SMEs) were investigated by optical density against strains of S. pneumoniae with different susceptibilities to benzylpenicillin. To validate the data, the PAE and PA SME of one susceptible and one resistant strain were also tested with the viable count method. The post-MIC effects (PMEs) were studied in an in vitro kinetic model, simulating human pharmacokinetics with a half-life of 1 h and a time above MIC of approximately 20% of 24 h. RESULTS: There were no differences with respect to the PAEs, PA SMEs and PMEs of benzylpenicillin for the various strains of S. pneumoniae, irrespective of their susceptibility to penicillin. For both some of the susceptible and resistant strains investigated, longer PA SMEs at 0.2 and 0.3 x MIC were noted, indicating that these parameters might be more dependent on the type of strain rather than on the susceptibility status. CONCLUSION: No differences in the pharmacodynamic response after similar drug exposure were seen for S. pneumoniae strains with different penicillin susceptibility.  相似文献   
95.
Introduction The nutritional status of women before, during, and after pregnancy plays an important role in the health of mother and child. In addition to a balanced mixed diet, the increased need for folic acid and iodine should be met and ensured with supplements. The aim of this study was to assess dietary supplementation in the context of pregnancy and to investigate the effect of targeted counselling on supplementation behavior during and after pregnancy. Methods In the context of the “Gesund leben in der Schwangerschaft” (GeliS; “Healthy living in pregnancy”) trial, women in the intervention group (IG) received four structured lifestyle counselling sessions during pregnancy as well as postpartum, during which they were informed about appropriate dietary supplementation. The women in the control group (CG) received routine prenatal care. The intake of dietary supplements was recorded at different points using a questionnaire. Results In total, 2099 women were included in the analysis. Prior to conception, 31.3% of the women in the IG and 31.4% of the women in the CG took folic acid supplements. Prenatally, about half of the women took folic acid (IG: 54.1%; CG: 52.0%) and iodine (IG: 50.2%; CG: 48.2%). Statistically significant differences between the groups with regard to supplementation behavior could not be observed, neither prior to inclusion in the study nor during the intervention. During pregnancy, 23.0% of all women took docosahexaenoic acid (DHA) supplements and 21.8% iron supplements. 49.4% of the women additionally took vitamin D supplements. A higher educational level (p < 0.001), advanced age (p < 0.001), primiparity (p < 0.001), and a vegetarian diet (p = 0.037) were all associated with a higher level of dietary supplementation. Conclusion The GeliS lifestyle counselling did not significantly improve the supplementation behavior of women during and after pregnancy. Women should be informed about adequate dietary supplementation early on within the scope of gynecological prenatal care. Key words: dietary supplementation, folic acid, iodine, pregnancy, postpartum  相似文献   
96.
Host cell proteases such as TMPRSS2 are critical determinants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) tropism and pathogenesis. Here, we show that antithrombin (AT), an endogenous serine protease inhibitor regulating coagulation, is a broad-spectrum inhibitor of coronavirus infection. Molecular docking and enzyme activity assays demonstrate that AT binds and inhibits TMPRSS2, a serine protease that primes the Spike proteins of coronaviruses for subsequent fusion. Consequently, AT blocks entry driven by the Spikes of SARS-CoV, MERS-CoV, hCoV-229E, SARS-CoV-2 and its variants of concern including Omicron, and suppresses lung cell infection with genuine SARS-CoV-2. Thus, AT is an endogenous inhibitor of SARS-CoV-2 that may be involved in COVID-19 pathogenesis. We further demonstrate that activation of AT by anticoagulants, such as heparin or fondaparinux, increases the anti-TMPRSS2 and anti-SARS-CoV-2 activity of AT, suggesting that repurposing of native and activated AT for COVID-19 treatment should be explored.  相似文献   
97.
Vasopressin (VP) and oxytocin (OT) are released within the hypothalamic nuclear region in response to direct microdialysis with hypertonic solutions. Experiments were performed to determine whether systemic osmotic stimulation causes changes in intranuclear peptide release within the supraoptic nucleus (SON). A hypertonic sodium chloride solution was injected intraperitoneally (ip) or intravenously (iv) and microdialysis techniques were used to simultaneously monitor central and peripheral peptide release in urethane anesthetized rats. Systemic osmotic stimuli elicited increases in intranuclear peptide release which were delayed and long-lasting, occurring over a 2.5 h period. In contrast, plasma peptide levels peaked at 30-min after the stimulus. The results demonstrate that increased plasma sodium elicits an increase in VP and OT release into the extracellular space of the hypothalamic SON. The different patterns of peptide release in plasma and brain point toward the possibility of independently regulated release into the different compartments.  相似文献   
98.
Aims: The aim of this study is to evaluate the value of early radiological investigations in predicting the long‐term neurodevelopmental outcome of infants with inflicted traumatic brain injury (ITBI). Methods: Clinical and radiological investigations of 24 infants with ITBI were performed during the acute phase of injury (1–3 days), and during the early (4 days up to 3 months) and late (>9 months) postinjury phases. The clinical outcome in survivors (n = 22) was based on the Rankin Disability Scale and the Glasgow Outcome Score. Results: Five out of 24 infants (21%) had a poor neurodevelopmental outcome (death and severe disability), 17 infants (71%) had different developmental problems and 2 infants were normal at the mean age of 62 (54–70) (95% CI) months. A low initial Glasgow Coma Scale score of 8 or below [p < 0.05, OR 13.0 (1.3–133.3)], the development of brain oedema [p < 0.005, OR 13.0 (1.6–773)], focal changes in the basal ganglia during the acute phase [p < 0.01, OR 45 (2.1–937.3)], the development of new intracerebral focal changes early postinjury [p < 0.05, OR 24.1(1.0–559.1)], a decrease in white matter [p < 0.01, OR 33 (1.37–793.4)] and the development of severe atrophy before 3 months postinjury [p < 0.05, OR 24 (11.0–559.1)] were significantly correlated with a poor neurodevelopmental outcome. Conclusions: Early clinical and radiological findings in ITBI are of prognostic value for neurodevelopmental outcome.  相似文献   
99.
Recently, we found sesame to be a major cause of severe IgE-mediated food allergic reactions among infants and young children in Israel. The purpose of this study was to describe the different patterns of sesame sensitivity. We have identified three subgroups among our patients (n = 32). Group I (n = 23, M/F; 14/9) consisted of cases with IgE-mediated sesame allergy. The mean age of the first allergic reaction was 11.7 months. Although the main clinical manifestation was urticaria/angiedema (n = 14, 60%), anaphylaxis was the presenting symptom in seven (30%) patients; all of them were younger than 1 year. Sixteen (70%) were found to be allergic to other foods, and other atopic diseases were identified in 18 (78%) patients. Three patients 'outgrew' their allergy within 1–2 years. Group II (n = 2) included cases in whom sesame allergy was ruled out based on a negative skin prick test (SPT) together with a negative open oral challenge. Group III (n = 7) consisted of patients that were found to be SPT positive for sesame as part of a screening for other food allergies. Although sesame products have become fashionable in westernized countries, early exposure may cause sesame to share eventually the same 'noteriety and fate' as peanut – a major cause of severe food allergic reactions.  相似文献   
100.
Some studies have demonstrated antidepressant activity of neurokinin-1-receptor antagonists (NK-1-RA) in major depressive disorder. However, the underlying mechanisms of this antidepressant effect are largely unknown. Preclinical studies in rats and mice have suggested that NK-1-RA do increase the neuronal release of serotonin (5-HT). This, however, seems to be compensated by an increased 5-HT reuptake, indicating that NK-1-RA have no inhibitory effect on the 5-HT transporter in rodents. Given the possibility that modulation of neurotransmitter release and reuptake may differ between species, with major differences found between rodents and humans, we investigated for the first time the possible modulatory effect of NK-1-RA on 5-HT uptake in human brain synaptosomes and compared it with the situation in rat cortex. We found that the specific human NK-1-RA L-733060, in contrast to the SSRI fluvoxamine (IC50 = 10− 7.96 M) did not inhibit 5-HT uptake in human brain synaptosomes and did not modulate fluvoxamine-induced 5-HT uptake inhibition at 1 μM. Furthermore, substance P as well as Sar9Met(O2)11SP, as the major agonists at the NK-1-R, did not modulate 5-HT uptake in human brain synaptosomes. Similar results were found in rat cortex synaptosomes by using the rat-specific NK-1-RA WIN51708. These results show that in humans, as in rodents, inhibition of the 5-HT transporter is probably not the underlying mechanism of the assumed antidepressant activity of NK-1-RA.  相似文献   
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