A subpopulation of astrocyte progenitors defined by Sonic hedgehog signaling

Background The molecular signaling pathway, Sonic hedgehog (Shh), is critical for the proper development of the central nervous system. The requirement for Shh signaling in neuronal and oligodendrocyte development in the developing embryo are well established. However, Shh activity is found in discrete subpopulations of astrocytes in the postnatal and adult brain. Whether Shh signaling plays a role in astrocyte development is not well understood. Methods Here, we use a genetic inducible fate mapping approach to mark and follow a population of glial progenitor cells expressing the Shh target gene, Gli1, in the neonatal and postnatal brain. Results In the neonatal brain, Gli1-expressing cells are found in the dorsolateral corner of the subventricular zone (SVZ), a germinal zone harboring astrocyte progenitor cells. Our data show that these cells give rise to half of the cortical astrocyte population, demonstrating their substantial contribution to the cellular composition of the cortex. Further, these data suggest that the cortex harbors astrocytes from different lineages. Gli1 lineage astrocytes are distributed across all cortical layers, positioning them for broad influence over cortical circuits. Finally, we show that Shh activity recurs in mature astrocytes in a lineage-independent manner, suggesting cell-type dependent roles of the pathway in driving astrocyte development and function. Conclusion These data identify a novel role for Shh signaling in cortical astrocyte development and support a growing body of evidence pointing to astrocyte heterogeneity.

The Impact of the COVID-19 Pandemic Lockdown on Pediatric Infections—A Single-Center Retrospective Study

Since the SARS-CoV-2 outbreak, many countries have introduced measures to limit the transmission. The data based on ICD-10 codes of lower respiratory tract infections and microbiological analysis of respiratory and gastrointestinal infections were collected. The retrospective five-year analysis of the medical records revealed a substantial decrease in respiratory tract infections during the pandemic year (from April 2020 to March 2021). We noted an 81% decline in the LRTI-associated hospital admissions based on the ICD-10 analysis (from a mean of 1170 admissions per year in the previous four years to 225 admissions between April 2020 through March 2021). According to microbiological analysis, there were 100%, 99%, 87%, and 47% drops in influenza virus, respiratory syncytial virus, rotavirus, and norovirus cases reported respectively during the pandemic season until April 2021 in comparison to pre-pandemic years. However, the prevalence of gastrointestinal bacterial infections was stable. Moreover, in August 2021, an unexpected rise in RSV-positive cases was observed. The measures applied during the COVID-19 pandemic turned out to be effective but also had a substantial contribution to the so-far stable epidemiological situation of seasonal infections.

Current Progress of Jatropha Curcas Commoditisation as Biodiesel Feedstock: A Comprehensive Review

This article looks at the national and global actors, social networks, and narratives that have influenced Jatropha’s worldwide acceptability as a biofuel crop. Jatropha Curcas is a genus of around 175 succulent shrubs and trees in the Euphorbiaceae family (some of which are deciduous, such as Jatropha Curcas L.). It’s a drought-tolerant perennial that thrives in poor or marginal soil and produces a large amount of oil per hectare. It is easy to grow, has a fast growth rate, and can generate seeds for up to 50 years. Jatropha Curcas has been developed as a unique and promising tropical plant for augmenting renewable energy sources due to its various benefits. It is deserving of being recognised as the only competitor in terms of concrete and intangible environmental advantages. Jatropha Curcas is a low-cost biodiesel feedstock with good fuel properties and more oil than other species. It is a non-edible oilseed feedstock. Thus it will have no impact on food prices or the food vs fuel debate. Jatropha Curcas emits fewer pollutants than diesel and may be used in diesel engines with equivalent performance. Jatropha Curcas also makes a substantial contribution to the betterment of rural life. The plant may also provide up to 40% oil yield per seed based on weight. This study looks at the features characteristics of Jatropha Curcas as biodiesel feedstock and performance, and emissions of internal combustion engine that operates on this biodiesel fuel.

Universal Germline Panel Testing for Individuals with Pheochromocytoma and Paraganglioma Produces High Diagnostic Yield

Background Practice guidelines to identify individuals with hereditary pheochromocytomas and paragangliomas (PPGLs) advocate for sequential gene testing strategy guided by specific clinical features and predate the routine use of multigene panel testing (MGPT). Objective To describe results of MGPT for hereditary PPGL in a clinically and ancestrally diverse cohort. Setting Commercial laboratory based in the United States. Methods Clinical data and test results were retrospectively reviewed in 1727 individuals who had targeted MGPT due to suspicion of hereditary PPGL from August 2013 through December 2019. Results Overall, 27.5% of individuals had a pathogenic or likely pathogenic variant (PV), 9.0% had a variant of uncertain significance, and 63.1% had a negative result. Most PVs were identified in SDHB (40.4%), followed by SDHD (21.1%), SDHA (10.1%), VHL (7.8%), SDHC (6.7%), RET (3.7%), and MAX (3.6%). PVs in FH, MEN1, NF1, SDHAF2, and TMEM127 collectively accounted for 6.5% of PVs. Clinical predictors of a PV included extra-adrenal location, early age of onset, multiple tumors, and positive family history of PPGL. Individuals with extra-adrenal PGL and a positive family history were the most likely to have a PV (85.9%). Restricting genetic testing to SDHB/C/D misses a third (32.8%) of individuals with PVs. Conclusion Our data demonstrate a high diagnostic yield in individuals with and without established risk factors, a low inconclusive result rate, and a substantial contribution to diagnostic yield from rare genes. These findings support universal testing of all individuals with PPGL and the use of concurrent MGPT as the ideal platform.

International Law in Greek

There has been a continuous presence and contribution of Greek jurists in the discipline of international law ever since the interwar years. Undoubtedly, Nicholas Politis and Stylianos Seferiades were the most prominent Greek international lawyers of the interwar period; the former a government lawyer and diplomat with substantial contribution in almost every aspect of the development of international law both in and out of the institutional context of the League of Nations and the latter an academic who held the first Chair of Public International Law at the Faculty of Law of the National and Kapodistrian University of Athens. They were followed in the 1950s to 1970s by Jean Spyropoulos, professor of international law (Thessaloniki and Athens, member of the International Law Commission, and International Court of Justice (ICJ) judge; Konstantin Eustathiades, professor of international law (Thessaloniki and Athens), member of the International Law Commission, and member of the European Commission of Human Rights; and George Tenekides, professor of international law at the Panteion School of Political Science, member of the European Commission of Human Rights, and member of the UN Committee on the Elimination of Racial Discrimination. Following the restoration of democracy in 1974 a new cohort of international lawyers has dominated the discipline of international law to the present day: Argyrios Fatouros, Christos Rozakis, Konstantin Economides, Emmanuel Roukounas, and Krateros Ioannou. They have each in their own capacity inspired a large number of their students to specialize in international law, a lot of which succeeded them as faculty teaching this subject, and have pursued and are still pursuing distinguished careers in international law both in Greece and abroad. Most of the Greek international lawyers are prolific authors of books and articles and even though the tendency among a growing number of them is to publish their research in English or French an equally large number publish in Greek. They tend to publish textbooks and monographs. As far as the latter are concerned, they cover areas of the law of particular interest for Greece, such as the law of the sea, international environmental law, and human rights law as well as classical subjects, such as the settlement of disputes, international institutions, and the law of armed conflict.

Different mechanisms of Arctic and Antarctic sea ice response to ocean heat transport

Understanding drivers of Arctic and Antarctic sea ice on multidecadal timescales is key to reducing uncertainties in long-term climate projections. Here we investigate the impact of ocean heat transport (OHT) on sea ice, using pre-industrial control simulations of 20 models participating in the latest Coupled Model Intercomparison Project (CMIP6). In all models and in both hemispheres, sea ice extent is negatively correlated with poleward OHT. However, the similarity of the correlations in both hemispheres hides radically different underlying mechanisms. In the northern hemisphere, positive OHT anomalies primarily result in increased ocean heat convergence along the Atlantic sea ice edge, where most of the ice loss occurs. Such strong, localised heat fluxes ($$\sim {}100~\text {W}~\text {m}^{-2}$$ ∼ 100 W m - 2 ) also drive increased atmospheric moist-static energy convergence at higher latitudes, resulting in a pan-Arctic reduction in sea ice thickness. In the southern hemisphere, increased OHT is released relatively uniformly under the Antarctic ice pack, so that associated sea ice loss is driven by basal melt with no direct atmospheric role. These results are qualitatively robust across models and strengthen the case for a substantial contribution of ocean forcing to sea ice uncertainty, and biases relative to observations, in climate models.

Multiple bacterial partners in symbiosis with the nudibranch mollusk Rostanga alisae

The discovery of symbiotic associations extends our understanding of the biological diversity in the aquatic environment and their impact on the host’s ecology. Of particular interest are nudibranchs that unprotected by a shell and feed mainly on sponges. The symbiotic association of the nudibranch Rostanga alisae with bacteria was supported by ample evidence, including an analysis of cloned bacterial 16S rRNA genes and a fluorescent in situ hybridization analysis, and microscopic observations. A total of 74 clones belonging to the phyla α-, β-, γ-Proteobacteria, Actinobacteria, and Cyanobacteria were identified. FISH confirmed that bacteriocytes were packed with Bradyrhizobium, Maritalea, Labrenzia, Bulkholderia, Achromobacter, and Stenotrophomonas mainly in the foot and notum epidermis, and also an abundance of Synechococcus cyanobacteria in the intestinal epithelium. An ultrastructural analysis showed several bacterial morphotypes of bacteria in epidermal cells, intestine epithelium, and in mucus layer covering the mollusk body. The high proportion of typical bacterial fatty acids in R. alisae indicated that symbiotic bacteria make a substantial contribution to its nutrition. Thus, the nudibranch harbors a high diversity of specific endo- and extracellular bacteria, which previously unknown as symbionts of marine invertebrates that provide the mollusk with essential nutrients. They can provide chemical defense against predators.

Drivers to Obesity—A Study of the Association between Time Spent Commuting Daily and Obesity in the Nepean Blue Mountains Area

Obesity has become a public health challenge in every country on this planet, with a substantial contribution to global mortality and morbidity. Studies of the built environment have shown some promise in understanding the drivers of this obesity pandemic. This paper contributes to this knowledge, by focusing on one aspect of the urban environment and asking whether there is an association between commuting and obesity in residents of the Nepean Blue Mountains area on the fringes of Sydney. This is a cross-sectional study with obesity being the dependent variable, and commuting the independent variable, where 45 min or less was defined as local and distant commute was more than 45 min. In the sample of 158 respondents, the risk of obesity was twice as likely in the distant commuters than in the local commuters (OR 2.04, 95% CI 1.051 to 3.962, p = 0.034). Investigation of possible mediators of this association was limited by sample size; however, mode of transport was found to be a significant mediator. The results support the design of cities to provide health supporting environments for all residents, including equitable access to employment at a reasonable distance and effective public transport.

Feline hypertrophic cardiomyopathy: reduced microvascular density and involvement of CD34+ interstitial cells

The sequence of pathological events in feline hypertrophic cardiomyopathy (fHCM) is still largely unknown, although we know that fHCM is characterized by interstitial remodeling in a macrophage-driven pro-inflammatory environment and that myocardial ischemia might contribute to its progression. This study aimed to gain further insights into the structural changes associated with interstitial remodeling in fHCM with special focus on the myocardial microvasculature and the phenotype of the interstitial cells. Twenty-eight hearts (16 hearts with fHCM and 12 without cardiac disease) were evaluated in the current study, with immunohistochemistry, RNA-in situ hybridization, and transmission electron microscopy. Morphometrical evaluations revealed a statistically significant lower microvascular density in fHCM. This was associated with structural alterations in capillaries that go along with a widening of the interstitium due to the accumulation of edema fluid, collagen fibers, and mononuclear cells that also proliferated locally. The interstitial cells were mainly of fibroblastic or vascular phenotype, with a substantial contribution of predominantly resident macrophages. A large proportion expressed CD34 mRNA, which suggests a progenitor cell potential. Our results indicate that microvascular alterations are key events in the pathogenesis of fHCM and that myocardial interstitial cell populations with CD34+ phenotype play a role in the pathogenesis of the disease.

Occupation and COVID-19 mortality in England: a national linked data study of 14.3 million adults

ObjectivesTo estimate occupational differences in COVID-19 mortality and test whether these are confounded by factors such as regional differences, ethnicity and education or due to non-workplace factors, such as deprivation or prepandemic health.MethodsUsing a cohort study of over 14 million people aged 40–64 years living in England, we analysed occupational differences in death involving COVID-19, assessed between 24 January 2020 and 28 December 2020.We estimated age-standardised mortality rates (ASMRs) per 100 000 person-years at risk stratified by sex and occupation. We estimated the effect of occupation on COVID-19 mortality using Cox proportional hazard models adjusted for confounding factors. We further adjusted for non-workplace factors and interpreted the residual effects of occupation as being due to workplace exposures to SARS-CoV-2.ResultsIn men, the ASMRs were highest among those working as taxi and cab drivers or chauffeurs at 119.7 deaths per 100 000 (95% CI 98.0 to 141.4), followed by other elementary occupations at 106.5 (84.5 to 132.4) and care workers and home carers at 99.2 (74.5 to 129.4). Adjusting for confounding factors strongly attenuated the HRs for many occupations, but many remained at elevated risk. Adjusting for living conditions reduced further the HRs, and many occupations were no longer at excess risk. For most occupations, confounding factors and mediators other than workplace exposure to SARS-CoV-2 explained 70%–80% of the excess age-adjusted occupational differences.ConclusionsWorking conditions play a role in COVID-19 mortality, particularly in occupations involving contact with patients or the public. However, there is also a substantial contribution from non-workplace factors.