Current knowledge suggests a complex role of C-peptide in human physiology, but its mechanism of action is only partially understood. The effects of C-peptide appear to be variable depending on the target tissue, physiological environment, its combination with other bioactive molecules such as insulin, or depending on its concentration. It is apparent that C-peptide has therapeutic potential for the treatment of vascular and nervous damage caused by type 1 or late type 2 diabetes mellitus. The question remains whether the effect is mediated by the receptor, the existence of which is still uncertain, or whether an alternative non-receptor-mediated mechanism is responsible. The Institute of Endocrinology in Prague has been paying much attention to the issue of C-peptide and its metabolic effect since the 1980s. The RIA methodology of human C-peptide determination was introduced here and transferred to commercial production. By long-term monitoring of C-peptide oGTT-derived indices, the Institute has contributed to elucidating the pathophysiology of glucose tolerance disorders. This review summarizes the current knowledge of C-peptide physiology and highlights the contributions of the Institute of Endocrinology to this issue., Daniela Vejrazkova, Marketa Vankova, Petra Lukasova, Josef Vcelak, Bela Bendlova., and Obsahuje bibliografii
Climate change and human activity are two linked factors that alter the spatiotemporal distribution of the available water. Assessing the relative contribution of the two factors on runoff changes can help the planners and managers to better formulate strategies and policies regarding regional water resources. In this work, using two typical sub-basins of the Yellow River as the study area, we first detected the trend and the breakpoint in the annual streamflow data with the Pettitt test during the period 1964–2011. Next, a Budyko-based climate elasticity model and a monthly hydrological model were employed as an integrated method to distinguish the relative contributions of climate change and human activities to the long-term changes in runoff. The results showed that a significant decline in the annual runoff occurred in the two sub-basins during the study period, and the abrupt change point in the annual runoff at the two subbasins both occurred in 1997. The conceptual hydrological model performed well in reproducing monthly runoff time series at the two sub-basins. The Nash-Sutcliffe efficiency (NSE) between observed and simulated runoff during the validation period exceeds 0.83 for the two sub-basins. Climate elasticity method and hydrological model give consistent attribution results: human activities are the major drivers responsible for the decreased annual runoff in the Ten Great Gullies Basin. The relative contributions of climate change and human activities to the changes in the annual runoff were 22–32% and 68–78%, respectively.
The title conveys all the elements of this article. The typologies of capitalist economies, the typologies of welfare regimes, and the typologies of rental and owner-occupied housing regimes should be synchronised and combined, not selectively, but systematically. Integration will have to determine the multiple levels to which these typologies can be applied and on which they can interact. Owing to the persistence of housing institutions and buildings, a long-term (historical) view is also suggested – at all levels of analysis.
Ethiopian rats (genus Stenocephalemys) represent a monophyletic group of Ethiopian endemic rodents that diverged in the Ethiopian Highlands during the Pleistocene. Because of the frequent occurrence of so-called reticulate evolution (i.e. repeated hybridization of partially diverged populations), their taxonomy has not been adequately resolved, despite the fact that they belong to the most abundant rodent genus in Ethiopia and are important as pests and carriers of pathogens (e.g. hantaviruses). Here we analysed material for 623 Stenocephalemys specimens using integrative taxonomy composed of genomic analyses (388 nuclear markers and complete mitogenomes), 2D-geometric morphometry of skulls and classical morphometry of external traits. The genus consists of six clearly defined gene pools (= species), characterized by specific morphology, ecology and distribution. Two of them, described here as new species, live in fragmented populations in Afroalpine habitats in the north-western part of the Ethiopian Highlands. We also showed that mitochondrial DNA is not applicable as a universal diagnostic tool for species discrimination in Stenocephalemys, because of multiple cases of mitochondrial introgression. This finding illustrates the utility of the genus as a suitable model for future studies of mito-nuclear coevolution along an elevational gradient.
In the Republic of Guinea (West Africa), the diversity and distribution of striped grass mice of the genus Lemniscomys is poorly known. In the course of long-term field surveys from 2003 to 2011, we collected 97 specimens from various regions of Guinea with the aim of characterizing the morphological and genetic diversity of the genus in the country. We performed an integrative study that allowed us to detect the existence of at least two species in the collected specimens. Two molecular clades, corresponding to different karyotypes, were recovered. By comparison with type specimens and using classical morphometric analyses, we are able to confirm the presence of L. linulus and L. striatus in Guinea. We redescribe the skull and dental characters of the poorly known L. linulus and report its standard karyotype formula (2N = 56, NFa = 66). We did not collect any L. zebra in Guinea despite its presence in South Mali. In conclusion, the distributions of L. striatus and L. linulus described for Guinea and, including the previously reported L. bellieri, three species are now known to occur in this country. We recognise these three species as valid pending further revision of the genus at a pan-African scale.
Cílem práce bylo prozkoumat vztahy mezi mírou organizovaných aktivit dětí v předškolním věku, přesvědčením matky o přirozeném vývoji a kvalitou strategické pomoci (scaffolding) během společné hry s dítětem. Výzkumu se zúčastnilo 34 dvojic matek se svými dětmi ve věku od 52 do 83 měsíců (z toho 14 matek s vysokoškolským vzděláním). Data byla získána pozorováním společné hry se stavebnicí a pomocí dotazníků zjišťujících postoj matky k vývoji dítěte a míru organizovaných aktivit dětí. Bylo zjištěno, že u vysokoškolsky vzdělaných matek a matek s vyšším přesvědčením o přirozeném vývoji se objevuje méně nekvalitního scaffoldingu oproti matkám bez vysokoškolského vzdělání a s nižším přesvědčením o přirozeném vývoji. Ačkoli do organizovaných aktivit mimo mateřskou školu zapisují své děti více matky s VŠ vzděláním, docházka do těchto aktivit v rámci mateřské školy se u dětí matek s různým vzděláním neliší. Přestože matky s vysokoškolským vzděláním mohou nadměrně strukturovat volný čas dítěti skrze organizované aktivity, nebyla zjištěna souvislost této tendence na poskytování autonomie ve hře, a tedy na kvalitu scaffoldingu. Práce přináší nový pohled na problematiku intenzivního rodičovství a nadměrné strukturace času., The purpose of this study was to find out and verify relationships between the amount of organized activities (OAs) of children in preschool age, mother’s trust in organismic development and maternal scaffolding quality during mother-child play. Thirty-four pairs of mothers and their children aged 52-83 months participated in this study. The data was collected through a questionnaire and by observation of the game. Results revealed that higher educated mothers and mothers with higher trust in organismic development showed less poor-quality scaffolding during play in comparison to mothers without higher education and to mothers with lower trust in organismic development. Although higher educated mothers can excessively structure their children’s leisure time through OAs, there did not appear any effect of this on the autonomy support during the play and therefore on the scaffolding quality. This study brings a new view to issues of intensive parenting and the excessive structuring of children’s time., Adéla Woznicová, Renata Hlavová, Petra Daňsová, Lenka Lacinová., and Obsahuje bibliografické odkazy
Thirty years after the return of grey wolves (Canis lupus) to the French Alps, the number of livestock losses is on the rise despite livestock guarding dogs (LGDs) being widely used. Their relevance is, therefore, questioned by some sheep owner associations. To date, no study has investigated how LGDs interact with wolves in pastures. We present the results of a 6-year study totalling 3,300 hours of direct night-time observations to record the nature, frequency and outcomes of LGD-wolf interactions in the southern French Alps. We recorded 476 wolf events in the presence of LGDs, including 175 interactions, 66% of which were agonistic. Most (65%) of the interactions occurred at a distance > 100 m from the flock and on average involved more LGDs than wolves. In the presence of LGDs, wolves approached the flocks 134 times resulting in no attack (65%), attacks with no sheep victim (24.6%), or attacks with ≥ 1 sheep victim (10.4%). Our results suggest that LGD-wolf interactions are complex and do not simply occur in the immediate vicinity of the flock. We recommend using groups > 6 LGDs and reinforcing the presence of LGDs in a wider radius around the flock to limit the presence of isolated groups of sheep and to improve protection against wolf attacks.
Angiotensin-converting enzyme 2 (ACE2) was identified as a molecule that mediates the cellular entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Several membrane molecules of the host cell must cooperate in this process. While ACE2 serves in a membrane receptor-mediating interaction with the surface spike (S) glycoprotein of SARS-CoV-2 located on the virus envelope, enzyme A disintegrin and metalloproteinase 17 (ADAM17) regulates ACE2 availability on the membrane and transmembrane protease serine 2 (TMPRSS2) facilitates virus-cell membrane fusion. Interestingly, ACE2, ADAM17 and TMPRSS2 show a daily rhythm of expression in at least some mammalian tissue. The circadian system can also modulate COVID-19 progression via circadian control of the immune system (direct, as well as melatonin-mediated) and blood coagulation. Virus/ACE2 interaction causes ACE2 internalization into the cell, which is associated with suppressed activity of ACE2. As a major role of ACE2 is to form vasodilatory angiotensin 1-7 from angiotensin II (Ang II), suppressed ACE2 levels in the lung can contribute to secondary COVID-19 complications caused by up-regulated, pro-inflammatory vasoconstrictor Ang II. This is supported by the positive association of hypertension and negative COVID-19 prognosis although this relationship is dependent on numerous comorbidities. Hypertension treatment with inhibitors of renin-angiotensin system does not negatively influence prognosis of COVID-19 patients. It seems that tissue susceptibility to SARS-CoV-2 shows negative correlation to ACE2 expression. However, in lungs of infected patient, a high ACE2 expression is associated with better outcome, compared to low ACE2 expression. Manipulation of soluble ACE2 levels is a promising COVID-19 therapeutic strategy
The parasite communities of predatory fish can be species rich and diverse, making them effective models for studying the factors influencing temporal and spatial variation in these communities. Over a ten-year period an initial study was done on the metazoan parasite communities of Scomberomorus sierra (Jordan et Starks) from four locations on the south-central Pacific coast of Mexico. Twenty-four metazoan parasite taxa were identified from 674 S. sierra specimens: three species of Monogenea, eight Digenea, one Cestoda, one Acanthocephala, four Nematoda, five Copepoda, and two Isopoda. The parasite communities were characterised by high ectoparasite species richness, with monogeneans and some didymozoid species being numerically dominant. Community structure and species composition varied between locations, seasons and sampling years. Similarity between the component parasite communities was generally low, despite the occurrence of a distinctive set of host-specialist parasites. Interannual or local variations in some biotic and abiotic environmental factors are possible causes of the observed variations in the structure and species composition of the parasite community of S. sierra. Ecological factors were therefore considered to have more influence than phylogenetic aspects (host phylogeny) on parasite community structure.
Climate change impacts environmental conditions that affect photosynthesis. This review examines the effect of combinations of elevated atmospheric CO2, long photoperiods, and/or unfavorable nitrogen supply. Under moderate stress, perturbed plant source-sink ratio and redox state can be rebalanced but may result in reduced foliar protein content in C3 plants and a higher carbon-to-nitrogen ratio of plant biomass. More severe environmental conditions can trigger pronounced photosynthetic downregulation and impair growth. We comprehensively evaluate available evidence that microbial partners may be able to support plant productivity under challenging environmental conditions by providing (1) nutrients, (2) an additional carbohydrate sink, and (3) regulators of plant metabolism, especially plant redox state. In evaluating the latter mechanism, we note parallels to metabolic control in photosymbioses and microbial regulation of human redox biology.