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205. Contralateral and ipsilateral arterial vasculature of the human uterus: the pilot results of an anatomical study

Creator:
Kristek, Jakub, Kachlik, David, Sticova, Eva, and Fronek, Jiri
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
anatomy, blood supply, collateral circulation, investigative techniques, and transplantation
Language:
English
Description:
Arterial blood to the human uterus is provided by a pair of uterine arteries (UA) and supported by terminal branches of ovarian (OA) and vaginal arteries (VA). Literature reports the existence of ipsilateral and contralateral anastomoses between these arteries and the UA, but data on the prevalence of such anastomoses are discrepant. The aim of this trial is to study whether contralateral and ipsilateral anastomoses exist. We studied nine human uterine specimens, which were obtained from (i) human cadavers (n = 6), (ii) uterine transplant recipients (n = 2), and (iii) one altruistic uterine donor (n = 1). We injected India ink into the graft through the UA of each specimen (n = 8) or OA (n = 1). We semiquantitatively observed and evaluated the extent of the injection on horizontal, vertical, and transmural levels. The dye permeated beyond the midline in 9/9 (100 %) cases. Nearcomplete/complete permeation to the contralateral side was observed in 6/9 (66 %) cases. The dye permeated ipsilaterally throughout all uterine levels in 8/8 cases (100 %) of UA injection. The entire wall of the myometrium was permeated in 2/9 (22 %) cases. In 7/9 (78 %) cases, the wall of the myometrium was permeated less than halfway through. In conclusions, the preliminary results of this study prove the existence of ipsilateral and contralateral anastomoses. Complete transmural injection was observed in only 22 % of cases; however, this finding does not provide information about the functional capacity of these anastomoses. More data and studies are necessary to make definitive conclusions.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

206. Contribution of selected vasoactive systems to blood pressure regulation in two models of chronic kidney disease

Creator:
Drábková, Natálie, Hojná, Silvie, Zicha, Josef, and Vaněčková, Ivana
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
hypertension, chronic kidney Disease, vasoactive systems, partial nephrectomy, and goldblatt hypertension
Language:
English
Description:
It is generally accepted that angiotensin II plays an important role in high blood pressure (BP) development in both 2-kidney-1- clip (2K1C) Goldblatt hypertension and in partial nephrectomy (NX) model of chronic kidney disease (CKD). The contribution of sympathetic nervous system and nitric oxide to BP control in these models is less clear. Partial nephrectomy or stenosis of the renal artery was performed in adult (10-week-old) male hypertensive heterozygous Ren-2 transgenic rats (TGR) and normotensive control Hannover Sprague Dawley (HanSD) rats and in Wistar rats. One and four weeks after the surgery, basal blood pressure (BP) and acute BP responses to the consecutive blockade of renin-angiotensin (RAS), sympathetic nervous (SNS), and nitric oxide (NO) systems were determined in conscious rats. Both surgical procedures increased plasma urea, a marker of renal damage; the effect being more pronounced following partial nephrectomy in hypertensive TGR than in normotensive HanSD rats with a substantially smaller effect in Wistar rats after renal artery stenosis. We demonstrated that the reninangiotensin system does not play so fundamental role in blood pressure maintenance during hypertension development in either CKD model. By contrast, a more important role is exerted by the sympathetic nervous system, the activity of which is increased in hypertensive TGR-NX in the developmental phase of hypertension, while in HanSD-NX or Wistar-2K1C it is postponed to the established phase. The contribution of the vasoconstrictor systems (RAS and SNS) was increased following hypertension induction. The role of NO-dependent vasodilation was unchanged in 5/6 NX HanSD and in 2K1C Wistar rats, while it gradually decreased in 5/6 NX TGR rats.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

207. Convergent photoperiodic plasticity in developmental rate in two species of insects with widely different thermal phenotypes

Creator:
Kutcherov, Dmitry, Lopatina, Elena B, and Balashov, Sergei
Format:
print, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
polokřídlí, brouci, mandelinkovití, fotoperiodismus, teplota, Hemiptera, beetles, Chrysomelidae, photoperiodism, temperature, Pyrrhocoridae, Scantius aegyptius, Coleoptera, Timarcha tenebricosa, body size, development, reaction norm, seasonality, 2, and 59
Language:
English
Description:
Growth and development rates in many insects are affected by photoperiod, which enables insects to synchronize their life histories with seasonal events, but this aspect of insect photoperiodism remains understudied. Here we use several experimental combinations of constant day length and temperature to determine whether there are quantitative developmental responses to photoperiod in the bug Scantius aegyptius and leaf beetle Timarcha tenebricosa. The thermal ecology of these two species is strikingly different: the former is thermophilic and active throughout summer and the latter is spring-active and avoids the hottest time of the year. In accordance with their contrasting natural thermal environments, S. aegyptius survives better and achieves a larger final body mass at the high experimental temperatures, while T. tenebricosa survives better and is heavier at the low experimental temperatures. Despite this polarity, long-day conditions accelerate larval development relative to a short-day photoperiod in both species, and this developmental response is stronger at low temperatures. Our re-visitation of previous literature in light of the new findings indicates that this similarity in photoperiodic response is superficial and that relatively faster development in midsummer is likely to have a different ecological role in summer- and spring-active species. In the former, it may allow completion of an additional generation during the favourable season, whereas in the latter, this acceleration likely ensures that the larval stage, which is vulnerable to heat, is completed before the onset of hot weather., Dmitry Kutcherov, Elena B. Lopatina, Sergei Balashov., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

208. Cooperative defence of colonial breeding house martins (Delichon urbicum) against nest-usurping house sparrows (Passer domesticus)

Creator:
Savvas , Ieziekel and Reuven, Yosef
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
Cyprus, colonial defence, and nest construction
Language:
English
Description:
The usurpation of house martin nests by house sparrows has previously been reported. However, our study demonstrates how neighbouring house martins cooperatively defended against nest-usurping attempts by house sparrows. House martins collectively helped a conspecific pair build their nest at a much faster pace than would be possible for the breeding pair alone, within several hours as compared to a couple of days, in order to overcome the continued attempts of house sparrows to usurp the partially built nest. In our study, between the two breeding seasons of 2018 and 2019, the number of breeding house martins at the study site decreased by almost 63% while in contrast the number of house sparrow breeding pairs increased almost sixfold. The number of usurped nests by house sparrows was comparatively higher in 2019 as compared to 2018.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

209. Correlation between host specificity and genetic diversity for the muscle-dwelling fish parasite Myxobolus pseudodispar: examples of myxozoan host-shift?

Creator:
Forró, Barbara and Eszterbauer, Edit
Format:
print, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
kaprovití, parazitologie, Cyprinidae, parasitology, Myxozoa, cross-infection, molecular phylogeny, SSU rDNA, host specificity, 2, and 59
Language:
English
Description:
Myxobolus pseudodispar Gorbunova, 1936 (Myxozoa) is capable of infecting and developing mature myxospores in several cyprinid species. However, M. pseudodispar isolates from different fish show up to 5% differences in the SSU rDNA sequences. This is an unusually large intraspecific difference for myxozoans and only some of the muscle-dwelling myxozoan species possess such a high genetic variability. We intended to study the correlation between the host specificity and the phylogenetic relationship of the parasite isolates, and to find experimental proof for the putatively wide host range of M. pseudodispar with cross-infection experiments and phylogenetic analyses based on SSU rDNA. The experimental findings distinguished 'primary' and less-susceptible 'secondary' hosts. With some exceptions, M. pseudodispar isolates showed a tendency to cluster according to the fish host on the phylogenetic tree. Experimental and phylogenetic findings suggest the cryptic nature of the species. It is likely that host-shift occurred for M. pseudodispar and the parasite speciation in progress might explain the high genetic diversity among isolates which are morphologically indistinguishable., Barbara Forró, Edit Eszterbauer., and Obsahuje bibliografii
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

210. Correlation between nongenomic action of C19-Steroids and COVID-19 severity

Creator:
Perusquía, Mercedes
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
androgens, COVID-19 severity, male sex steroids, nongenomic actions, and coronavirus infection
Language:
English
Description:
The recent COVID-19 pandemic is the defining global health crisis of our time and little is known about this disease. It has been reported that advanced age is considered a major risk factor for COVID-19 complications, and data suggest that this disease is deadlier for men than women but these observations are currently unclear. Regarding androgen action, it has been shown that certain smooth muscles are a target for androgens by inducing an acute relaxing effect in airway and vascular tissues that is nongenomically mediated; likewise, androgens are capable of inducing genomic anti-inflammatory and nongenomic hypotensive responses. The aim of this report is to associate the relationship between COVID-19 and aging men as well as the comorbidities presented in this group of patients linked with androgen deficiency. Remarkably, the nongenomic mechanisms of androgens as potential protectors are reviewed. On this basis, it is suggested that hypotestosteronemia may be a risk factor for COVID-19 severity.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public