We are facing an unprecedented time during the COVID-19 pandemic. Measures have been taken to reduce the spread of the virus, including school closures and widespread lockdowns. Physical isolation ...combined with economic instability, fear of infection, and uncertainty for the future has had a profound impact on global mental health. For adolescents, the effects of this stress may be heightened due to important developmental characteristics. Canadian adolescents (n = 1,054; Mage = 16.68, SD = 0.78) completed online surveys and responded to questions on stress surrounding the COVID-19 crisis, feelings of loneliness and depression, as well as time spent with family, virtually with friends, doing schoolwork, using social media, and engaging in physical activity. Results showed that adolescents are very concerned about the COVID-19 crisis and are particularly worried about schooling and peer relationships. COVID-19 stress was related to more loneliness and more depression, especially for adolescents who spend more time on social media. Beyond COVID-19 stress, more time connecting to friends virtually during the pandemic was related to greater depression, but family time and schoolwork was related to less depression. For adolescents with depressive symptoms, it may be important to monitor the supportiveness of online relationships. Results show promising avenues to stave off loneliness, as time with family, time connecting to friends, as well as physical activity were related to lower loneliness, beyond COVID-19 stress. These results shed light on the implications of the COVID-19 pandemic for adolescents and document possible pathways to ameliorate negative effects.
Nous nous trouvons, avec la pandémie de COVID-19, dans une situation sans précédent. Des mesures ont été prises pour réduire la propagation du virus, notamment des fermetures d'établissements scolaires et des confinements à grande échelle. L'isolement physique, combiné à l'instabilité économique, à la crainte de l'infection et à l'incertitude quant à l'avenir, a eu de profondes répercussions sur la santé mentale globale. Chez les adolescents, les effets de ce stress peuvent être exacerbés en raison des caractéristiques importantes du développement. Des adolescents canadiens (n = 1 054; Mage = 16,68, écart-type = 0,78) ont répondu à un sondage en ligne comportant des questions sur le stress dû à la crise de la COVID-19, le sentiment de solitude et de dépression, ainsi que le temps passé avec la famille ou les amis (virtuellement), ainsi que le temps consacré aux devoirs, aux médias sociaux et à l'activité physique. Les résultats ont démontré que les adolescents sont très préoccupés par la crise de la COVID-19, et qu'ils sont particulièrement inquiets par rapport à leurs études et aux relations avec leurs pairs. Le stress dû à la COVID-19 était lié à une plus grande solitude et à la hausse des cas de dépression, en particulier chez les adolescents qui passent plus de temps sur les médias sociaux. Outre le stress dû à la COVID-19, le fait de passer plus de temps en contact virtuel avec ses amis durant la pandémie était lié à une hausse des cas de dépression, tandis que le temps passé en famille ou consacré aux devoirs était lié à une incidence moindre de la dépression. Dans le cas des adolescents souffrant de symptômes de dépression, il pourrait être important de surveiller le niveau de soutien fourni par les relations en ligne. Les résultats laissent entrevoir des pistes prometteuses pour prévenir la solitude. Notamment, le temps en famille, le temps consacré aux contacts avec les amis, ainsi que l'activité physique étaient liés à une diminution de la solitude dans le contexte du stress lié à la COVID-19. Ces résultats permettent de mieux comprendre les répercussions de la pandémie de COVID-19 sur les adolescents et font état de possibles voies d'intervention pour atténuer les conséquences négatives.
Public Significance Statement
Adolescents are concerned about the COVID-19 crisis and their pandemic stress is related to heightened depression and loneliness. However, time with family, time connecting virtually to friends, as well as physical activity were related to less loneliness during the initial COVID-19 crisis. On the contrary, although more time on social media and virtually connecting to friends was related to more reported depression, time engaging with family was related to less reported depression.
Matrix vesicles have been implicated in the mineralization of calcified cartilage, bone and dentin for more than 40 years. During this period, their exact role, if any in the nucleation of ...hydroxyapatite mineral, and its subsequent association with the collagen fibrils in the organic matrix has been debated and remains controversial.
This review summarizes studies spanning the whole history of matrix vesicles, but emphasizes recent findings and several hypotheses which have been recently introduced to explain in greater detail how matrix vesicles function in biomineralization.
It is now generally accepted that matrix vesicles have some role(s) in mineralization; that they are the initial site of mineral formation; that MV bud from the plasma membrane of mineral forming cells, but that they take with them only a subset of the materials found in the parent membrane; that the three proteins, alkaline phosphatase, nucleotide pyrophosphatase phosphodiesterase and annexin V have important roles in the process and that matrix vesicles participate in regulating the concentration of PPi in the matrix. In contrast, many open questions remain to be answered.
Understanding the role of matrix vesicles in biomineralization will increase our knowledge of this important process.
In normal healthy individuals, mineral formation is restricted to specialized tissues which form the skeleton and the dentition. Within these tissues, mineral formation is tightly controlled both in ...growth and development and in normal adult life. The mechanism of calcification in skeletal and dental tissues has been under investigation for a considerable period. One feature common to almost all of these normal mineralization mechanisms is the elaboration of matrix vesicles, small (20–200 nm) membrane particles, which bud off from the plasma membrane of mineralizing cells and are released into the pre-mineralized organic matrix. The first crystals which form on this organic matrix are seen in and around matrix vesicles. Pathologic ectopic mineralization is seen in a number of human genetic and acquired diseases, including calcification of joint cartilage resulting in osteoarthritis and mineralization of the cardiovasculature resulting in exacerbation of atherosclerosis and blockage of blood vessels. Surprisingly, increasing evidence supports the contention that the mechanisms of soft tissue calcification are similar to those seen in normal skeletal development. In particular, matrix vesicle-like membranes are observed in a number of ectopic calcifications. The purpose of this review is to describe how matrix vesicles function in normal mineral formation and review the evidence for their participation in pathologic calcification.
A new software package, RASPA, for simulating adsorption and diffusion of molecules in flexible nanoporous materials is presented. The code implements the latest state-of-the-art algorithms for ...molecular dynamics and Monte Carlo (MC) in various ensembles including symplectic/measure-preserving integrators, Ewald summation, configurational-bias MC, continuous fractional component MC, reactive MC and Baker's minimisation. We show example applications of RASPA in computing coexistence properties, adsorption isotherms for single and multiple components, self- and collective diffusivities, reaction systems and visualisation. The software is released under the GNU General Public License.
Recent studies of genomic variation associated with autism have suggested the existence of extreme heterogeneity. Large-scale transcriptomics should complement these results to identify core ...molecular pathways underlying autism. Here we report results from a large-scale RNA sequencing effort, utilizing region-matched autism and control brains to identify neuronal and microglial genes robustly dysregulated in autism cortical brain. Remarkably, we note that a gene expression module corresponding to M2-activation states in microglia is negatively correlated with a differentially expressed neuronal module, implicating dysregulated microglial responses in concert with altered neuronal activity-dependent genes in autism brains. These observations provide pathways and candidate genes that highlight the interplay between innate immunity and neuronal activity in the aetiology of autism.
Two phase 3, double-blind studies in hospitalized adults with complicated skin and skin-structure infections (cSSSI) determined the safety and efficacy of tigecycline versus that of ...vancomycin-aztreonam. Patients received tigecycline (100 mg, followed by 50 mg intravenously twice daily) or vancomycin (1 g intravenously twice daily) plus aztreonam (2 g intravenously twice daily) for up to 14 days. Populations were as follows: 1116 patients (566 treated with tigecycline, and 550 treated with vancomycin-aztreonam) constituted the modified intent-to-treat (mITT) population, 1057 patients (538 treated with tigecycline, and 519 treated with vancomycin-aztreonam) constituted the clinical mITT (c-mITT) population, and 833 patients (422 treated with tigecycline, and 411 treated with vancomycin-aztreonam) constituted the clinically evaluable population. Clinical responses to tigecycline and vancomycin-aztreonam at test-of-cure were similar: c-mITT, 79.7% (95% confidence interval CI, 76.1%–83.1%) versus 81.9% (95% CI, 78.3%–85.1%) (P = .4183); and clinically evaluable, 86.5% (95% CI, 82.9%–89.6%) versus 88.6% (95% CI, 85.1%–91.5%) (P = .4233). Adverse events were similar, with increased nausea and vomiting in the tigecycline group and increased rash and elevated hepatic aminotransferase levels in the vancomycin-aztreonam group. Tigecycline monotherapy is as safe and efficacious as the vancomycin-aztreonam combination in treating patients with cSSSI.
Odontogenic keratocysts (OKC) are benign but aggressive lesions. As there is a lack of well randomized clinical studies assessing the effectiveness of the different treatment options for OKC, a ...network meta-analysis (NMA) was performed to identify the best treatment option with the lowest recurrence rate. An electronic search was performed following the PRISMA guidelines to identify all clinical studies comparing treatment options against enucleation alone. The outcome variable was recurrence. The predictor variables were treatments. The eight included treatments were: enucleation with peripheral ostectomy/curettage (E + PO/curettage); enucleation with cryotherapy (E + CRYO); enucleation with/without PO followed by modified Carnoy’s solution (E ± PO+MCS); enucleation with PO and with topical 5-fluorouracil (E + PO+5FU); enucleation with/without PO followed by original Carnoy’s solution (E ± PO+CS); marsupialization alone (MARS); marsupialization followed by secondary enucleation with/without PO (MARS+2°E ± PO); and resection. The odds ratio was used to estimate the recurrence rate. A frequentist NMA was performed using Stata software. A total of 2989 patients in 40 studies were included. Both direct pairwise meta-analysis and NMA showed that E + 5FU+PO was significantly superior to E ± PO+MCS. However, no statistically significant difference was found between E ± PO+CS vs E + 5FU+PO, E ± PO+MCS, and resection, respectively (all very low quality evidence). The three most effective treatments in reducing the recurrence rate were E + PO+ 5FU (98.1%; very low quality evidence), resection (83.5%; very low quality evidence), and E ± PO+CS (63.8%; moderate quality evidence). The findings from this study suggest that CS remains the most effective fixative agent after enucleation and PO until proven otherwise. Additionally, 5FU appears to be an effective method with promising results that needs further research. Finally, the efficacy of MCS remains controversial; further in vivo and in vitro studies are required to determine new protocols. As this NMA included retrospective studies, the results should be interpreted with great caution (level of evidence: type III).
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