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61.
62.
BackgroundTeachers are at heightened risk of poor mental health and well-being, which is likely to impact on the support they provide to students, and student outcomes. We conducted a cluster randomised controlled trial, to test whether an intervention to improve mental health support and training for high school teachers led to improved mental health and well-being for teachers and students, compared to usual practice. We also conducted a cost evaluation of the intervention.Methods and findingsThe intervention comprised (i) Mental Health First Aid training for teachers to support students; (ii) a mental health awareness session; and (iii) a confidential staff peer support service. In total 25 mainstream, non-fee-paying secondary schools stratified by geographical area and free school meal entitlement were randomly allocated to intervention (n = 12) or control group (n = 13) after collection of baseline measures. We analysed data using mixed-effects repeated measures models in the intention-to-treat population, adjusted for stratification variables, sex, and years of experience. The primary outcome was teacher well-being (Warwick-Edinburgh Mental Well-being Scale). Secondary outcomes were teacher depression, absence, and presenteeism, and student well-being, mental health difficulties, attendance, and attainment. Follow-up was at months 12 (T1) and 24 (T2). We collected process data to test the logic model underpinning the intervention, to aid interpretation of the findings. A total of 1,722 teachers were included in the primary analysis. Teacher well-being did not differ between groups at T2 (intervention mean well-being score 47.5, control group mean well-being score 48.4, adjusted mean difference −0.90, 95% CI –2.07 to 0.27, p = 0.130). The only effect on secondary outcomes was higher teacher-reported absence among the intervention group at T2 (intervention group median number of days absent 0, control group median number of days absent 0, ratio of geometric means 1.04, 95% CI 1.00 to 1.09, p = 0.042). Process measures indicated little change in perceived mental health support, quality of relationships, and work-related stress. The average cost of the intervention was £9,103 per school. The study’s main limitations were a lack of blinding of research participants and the self-report nature of the outcome measures.ConclusionsIn this study, we observed no improvements to teacher or student mental health following the intervention, possibly due to a lack of impact on key drivers of poor mental health within the school environment. Future research should focus on structural and cultural changes to the school environment, which may be more effective at improving teacher and student mental health and well-being.Trial registrationwww.isrctn.com ISRCTN95909211.

Using a cluster randomized study, Judi Kidger and colleagues study an intervention to improve teacher wellbeing support and training to support students in UK high schools (the WISE study).  相似文献   
63.
During Trypanosoma cruzi cell invasion, signal transduction pathways are triggered in parasite and host cells, leading to a rise in intracellular Ca(2+) concentration. We posed the question whether calcineurin (CaN), in particular the functional regulatory subunit CaNB, a Ca(2+)-binding EF-hand protein, was expressed in T. cruzi and whether it played a role in cell invasion. Here we report the cloning and characterization of CL strain CaNB gene, as well as the participation of CaNB in cell invasion. Treatment of metacyclic trypomastigotes (MT) or tissue-culture trypomastigotes (TCT) with the CaN inhibitors cyclosporin or cypermethrin strongly inhibited (62-64%) their entry into HeLa cells. In assays using anti-phospho-serine/threonine antibodies, a few proteins of MT were found to be dephosphorylated in a manner inhibitable by cyclosporin upon exposure to HeLa cell extract. The phosphatase activity of CaN was detected by a biochemical approach in both MT and TCT. Treatment of parasites with antisense phosphorothioate oligonucleotides directed to TcCaNB-CL, which reduced the expression of TcCaNB and affected TcCaN activity, resulted in approximately 50% inhibition of HeLa cell entry by MT or TCT. Given that TcCaNB-CL may play a key role in cell invasion and differs considerably in its primary structure from the human CaNB, it might be considered as a potential chemotherapeutic target.  相似文献   
64.
Novel racemic indeno[1,2-e]pyrimido[4,5-b][1,4]diazepine-5,11-diones 3-29 were obtained regioselectivily from the reaction of 5,6-diamino-3,4-dihydropyrimidin-4-ones 1 and 2-arylideneindandiones 2 as reagents. These compounds have been evaluated at the US National Cancer Institute (NCI) for their ability to inhibit approximately 60 different human tumor cell lines, where 5 and 6 presented remarkable activity against 57 and 48 cancer cell lines, respectively, with the most important GI(50) values ranging from 0.49 to 1.46 microM, in vitro assay.  相似文献   
65.
The vesicular acetylcholine (ACh) transporter (VAChT) mediates ACh storage by synaptic vesicles. However, the VAChT-independent release of ACh is believed to be important during development. Here we generated VAChT knockout mice and tested the physiological relevance of the VAChT-independent release of ACh. Homozygous VAChT knockout mice died shortly after birth, indicating that VAChT-mediated storage of ACh is essential for life. Indeed, synaptosomes obtained from brains of homozygous knockouts were incapable of releasing ACh in response to depolarization. Surprisingly, electrophysiological recordings at the skeletal-neuromuscular junction show that VAChT knockout mice present spontaneous miniature end-plate potentials with reduced amplitude and frequency, which are likely the result of a passive transport of ACh into synaptic vesicles. Interestingly, VAChT knockouts exhibit substantial increases in amounts of choline acetyltransferase, high-affinity choline transporter, and ACh. However, the development of the neuromuscular junction in these mice is severely affected. Mutant VAChT mice show increases in motoneuron and nerve terminal numbers. End plates are large, nerves exhibit abnormal sprouting, and muscle is necrotic. The abnormalities are similar to those of mice that cannot synthesize ACh due to a lack of choline acetyltransferase. Our results indicate that VAChT is essential to the normal development of motor neurons and the release of ACh.Cholinergic neurotransmission has key functions in life, as it regulates several central and peripheral nervous system outputs. Acetylcholine (ACh) is synthesized in the cytoplasm by the enzyme choline acetyltransferase (ChAT) (16). Choline supplied by the high-affinity choline transporter (CHT1) is required to maintain ACh synthesis (52). A lack of ChAT (4, 35) or the high-affinity choline transporter (21) in genetically modified mice is incompatible with life. ACh plays an important role in wiring the neuromuscular junction (NMJ) during development (38, 43). Embryonic synthesis of ACh is fundamental for the development of proper nerve-muscle patterning at the mammalian NMJ, as ChAT-null mice present aberrant nicotinic ACh receptor (nAChR) localization and increased motoneuron (MN) survival, axonal sprouting, and branching (4, 35).The vesicular ACh transporter (VAChT) exchanges cytoplasmic ACh for two vesicular protons (37, 41). Previously reported electrophysiological studies showed that quantal size is decreased by vesamicol, an inhibitor of VAChT, but only in nerve terminals that have been electrically stimulated (19, 59, 60, 63). VAChT overexpression in developing Xenopus MNs increases both the size and frequency of miniature-end-plate currents (54). In Caenorhabditis elegans, mutations in VAChT affect behavior (65). Moreover, a decrease in VAChT expression has functional consequences for mammals, as mutant mice with a 70% reduction in the expression levels of this transporter (VAChT knockdown [KDHOM] mice) are myasthenic and have cognitive deficits (47). Hence, vesicular transport activity is rate limiting for neurotransmission “in vivo” (18, 47).Exocytosis of synaptic vesicle contents is the predominant mechanism for the regulated secretion of neurotransmitters (55). However, alternative mechanisms of secretion have been proposed (20, 56, 61). Quantal ACh release, comparable to that seen in developing nerve terminals, has been detected in myocytes and fibroblasts in culture, which presumably do not express VAChT (14, 24). More recently, it was found that the correct targeting of Drosophila photoreceptor axons is disrupted in flies with null mutations in ChAT (64). Remarkably, the inactivation of VAChT did not produce the same result (64). The result suggests that the release of ACh during development is not dependent on VAChT, perhaps because it is nonvesicular or because vesicular storage can occur without VAChT.To test if the VAChT-independent secretion of ACh has any physiological role in the mammalian nervous system, we generated a mouse line in which the VAChT gene is deleted. These mice lack the stimulated release of ACh from synaptosomes, die after birth, and show several alterations in neuromuscular wiring consistent with a severe decrease in the cholinergic input to muscles during development. These experiments indicate that VAChT has an important role in maintaining activity-dependent ACh release that supports life and the correct patterning of innervation at the NMJ.  相似文献   
66.
Nine taxa of the Sideritis genus, Sideritis argosphacelus var. spicata, Sideritis candicans var. eriocephala,Sideritis discolor, Sideritis kuegleriana, Sideritis lotsyi, Sideritis lotsyi var. mascaensis, Sideritis marmorea, Sideritis soluta and Sideritis tenoi, which are endemic from the Canary Islands, have been chemically studied. The diterpene sicanatriol 7β,18-diacetate was obtained from S.argosphacelus var. spicata, whilst a nor-diterpene, epiadejone, and the 3(2H)-benzofuranone solutin have been found in S. soluta. Another diterpene, sidendrodiol 18-monoacetate, has been isolated from S.argosphacelus var. spicata, for the first time as a natural product. Known sesquiterpenes, diterpenes, triterpenes, sterols, flavones, coumarins and other aromatic derivatives have also been isolated. These studies support the botanical division of the genus into two subgenera, Sideritis and Marrubiastrum, the three sections of the latter subgenus, Cretica, Empedocleopsis and Marrubiastrum, and the elevation of S. argosphacelus var. spicata, S. candicans var. eriocephala and S. lotsyi var. mascaensis to the rank of species.  相似文献   
67.
Three different monoclonal antibodies were produced against Trypanosona cruzi proteasomes. These antibodies were shown to react with a single 27-kDa band on immunoblots of purified proteasomes. Using a 7E5 monoclonal antibody (IgG1) that recognized the α5 subunit of protozoan protease we have studied the intracellular distribution of the T. cruzi 20S proteasome. Contrary to all cell types described to date, T. cruzi 20S proteasome was found not only in the cytoplasm and nucleus but also in the kinetoplast. As revealed by confocal microscopy, the reactivity of monoclonal antibody 7E5 was highly specific for protozoan proteasome because the antibody recognized only the proteasomes from parasites and not those from the mammalian host in T. cruzi infected cells. These findings were confirmed by immunoblots or immunoprecipitations, followed by chymotrypsin-like activity detection in kinetoplasts isolated by differential centrifugation and sucrose density gradients. Proteasome 20S was present in all T. cruzi stages and only slight differences in terms of relative abundance were found. The potential role of the proteasome in kinetoplast remodeling remains to be determined.  相似文献   
68.
A theoretical study on (ZrO2) n (n = 1–5) and Cu/ZrO2 oligomers is presented, DFT/B3LYP/6-31G** calculations along with Lanl2DZ pseudopotentials on metallic centers have been used to predict ionization potentials and electron affinities, chemical potentials and bandgaps indicating that the reactivity reaches reasonably constant values at n = 5. The effect of copper atoms adsorbed on (ZrO2) n is discussed and the reactivity of oligomers of ZrO2 and Cu/ZrO2 are compared, results indicate that Cu activates the systems by localizing the specific nucleophilic and electrophilic reactivity.  相似文献   
69.
70.
Understanding the recovery dynamics of ecosystems presents a major challenge in the human-impacted tropics. We tested whether secondary forests follow equilibrium or non-equilibrium dynamics by evaluating community reassembly over time, across different successional stages, and among multiple life stages. Based on long-term and static data from six 1-ha plots in NE Costa Rica, we show that secondary forests are undergoing reassembly of canopy tree and palm species composition through the successful recruitment of seedlings, saplings, and young trees of mature forest species. Such patterns were observed over time within sites and across successional stages. Floristic reassembly in secondary forests showed a clear convergence with mature forest community composition, supporting an equilibrium model. This resilience stems from three key factors co-occurring locally: high abundance of generalist species in the regional flora, high levels of seed dispersal, and local presence of old-growth forest remnants.  相似文献   
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