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Simple Summary: The fate and development of birds largely depend on their reproductive strategies, which vary, either diverging or converging among different species and populations. We studied the reproductive strategies of White-rumped Shama (Copsychus malabarica) and Oriental Magpie Robin (C. saularis), which may be convergent because of their kin relationships or divergent because of niche differentiation under sympatric competition. We observed that they differed in certain reproductive strategies, such as nest-site selection and egg incubation patterns, but were similar in others, including nestling heating, sexual synchronization in nestling feeding, and coordination of nestling feeding and nest cleaning. Reproduction plays a crucial role in determining the development, fate, and dynamics of bird populations. However, reproductive strategies vary among species and populations. In this study, we investigated the reproductive strategies of the Oriental Magpie Robin (Copsychus saularis) and White-rumped Shama (C. malabarica), which are closely related passerines that reproduce in sympatric areas. We found that although these two species were both cavity nesting, their nest-site selection differed; the Shama preferred nesting close to trees and forests, whereas the Magpie Robin nested close to human residential areas. Furthermore, their egg incubation patterns differed; the Shama increased daily incubation frequency with incubation time, but the Magpie Robin maintained its daily incubation time regardless of changes in incubation frequency. However, the nestling heating patterns of these two species were similar, indicating a critical demand for regulating hatchling body temperature during this crucial stage. The feeding frequencies of male parents were strongly correlated with those of females in both species, suggesting equal contribution and good synchronization between the sexes. Nestling feeding frequency was also correlated with nest cleaning frequency, implying coordination between feeding and defecation by parents and offspring, respectively. This research explored the divergence and convergence of reproductive strategies between these two sympatric species, providing valuable insights into the niche differentiation theory. [ABSTRACT FROM AUTHOR]

Synthetic glucocorticoids are commonly given to pregnant women when premature delivery threatens. Antenatal administration of clinically relevant doses of betamethasone to pregnant sheep causes sex-specific compromises of renal function and increases in blood pressure in adult offspring. However, it is unclear whether such effects are present in immature lambs. Therefore, the aims of the present study were to determine whether antenatal betamethasone at 80-81 days of gestation increases blood pressure and adversely impacts renal function in adolescent ewes and rams. Prenatal steroid exposure increased blood pressure significantly in the young male (84- 2 vs. 74 - 3 mmHg) and female sheep (88 - 5 vs. 79- 4), but it did not alter basal glomerular filtration rate, renal blood flow (RBF), or sodium excretion in either sex. However, antenatal betamethasone exposure blocked increases in RBF (P = 0.001), and enhanced excretion of an acute Na load (P < 0.05) in response to systemic infusions of angiotensin (ANG)-(1-7) at 10 pmol x [kg.sup.-l] x [min.sup.-1] in males. In females, the natriuretic response to combined ANG-(1-7), and Na load was significantly altered by prenatal betamethasone exposure. These findings indicate that blood pressure is increased in immature animals in response to antenatal steroid exposure and that sex-specific effects on renal function also exist. These changes may reflect greater risk for further loss of renal function with age. prenatal steroid exposure; Na load; glomerular filtration rate; Na excretion; angiotensin-(1-7) doi: 10.1152/ajpregu.00590.2009.

Contag SA, Bi J, Chappell MC, Rose JC. Developmental effect of antenatal exposure to betamethasone on renal angiotensin H activity in the young adult sheep. Am J Physiol Renal Physiol 298: F847-F856, 2010. First published January 13, 2010; doi:10.1152/ajprenal.00497.2009.--Antenatal corticosteroids may have long-term effects on renal development which have not been clearly defined. Our objective was to compare the responses to intrarenal infusions of ANG II in two groups of year-old, male sheep: one group exposed to a clinically relevant dose of betamethasone before birth and one not exposed. We wished to test the hypothesis that antenatal steroid exposure would enhance renal responses to ANG II in adult life. Six pairs of male sheep underwent unilateral nephrectomy and renal artery catheter placement. The sheep were infused for 24 h with ANG II or with ANG II accompanied by blockade of the angiotensin type 1 (A[T.sub.1]) or type 2 (AT2) receptor. Baseline mean arterial blood pressure among betamethasone-exposed sheep was higher than in control animals (85.8 [+ or -] 2.2 and 78.3 [+ or -] 1.0 mmHg, respectively, P = 0.003). Intrarenal infusion of ANG II did not increase systemic blood pressure (P [greater than or equal to] 0.05) but significantly decreased effective renal plasma flow and increased renal artery resistance (P < 0.05). The decrease in flow and increase in resistance were significantly greater in betamethasone- compared with vehicleexposed sheep (betamethasone P < 0.05, vehicle P [greater than or equal to] 0.05). This effect appeared to be mediated by a heightened sensitivity to the A[T.sub.1] receptor among betamethasone-exposed sheep. Sodium excretion initially decreased in both groups during ANG II infusion; however, a rebound was observed after 24 h. A[T.sub.1] blockade was followed by a significant rebound after 24 h in both groups. A[T.sub.2] blockade blunted the 24-h rebound effect among the vehicle-exposed sheep compared with the betamethasone-exposed sheep. In conclusion, antenatal corticosteroid exposure appears to modify renal responsiveness to ANG II by increasing A[T.sub.1]- and decreasing A[T.sub.2] receptor-mediated actions particularly as related to renal blood flow and sodium excretion. angiotensin receptor; renal plasma flow; glomerular filtration rate; corticosteroids doi: 10.1152/ajprenal.00497.2009.

Exposure to clinically relevant doses of glucocorticoids during fetal life increases blood pressure in adult male and female sheep. The purpose of this study was to evaluate the effects of prenatal exposure to betamethasone at 80-81 days of gestation on renal function in ewes and rams at 1.5 yr of age. In prenatal betamethasone-exposed males, compared with the vehicle-exposed animals, basal glomerular filtration rate (GFR) (1.93 [+ or -] 0.08 vs. 2.27 [+ or -] 0.10 ml * [min.sup.-1] * kg body [wt.sup. 1]) and the ability to excrete an acute [Na.sup.+] load (37.1 [+ or -] 4.4 vs. 53.7 [+ or -] 9.7%) were reduced. (P < 0.03 and P = 0.03, respectively). In contrast, prenatal betamethasone exposure had no effect on basal GFR, [Na.sup.+] excretion, or the percentage of the [Na.sup.+] load excreted during the experiment in females. Systemic infusions of ANG-(1-7) at 9 ng * [min.sup.-1] * [kg.sup.-1] for 2 h had minimal effects on basal GFR, renal plasma flow, and [Na.sup.+] excretion in males but increased [Na.sup.+] excretion in females. However, the percentage of [Na.sup.+] load excreted during ANG-(1-7) infusion did not change in prenatal betamethasone-exposed females (113.1 [+ or -] 14.2 vs. 98.1 [+ or -] 12.2%) compared with the significant increase in vehicle females (139.2 [+ or -] 22.3 vs. 92.2 [+ or -] 7.5%) (P = 0.01). The data indicate that antenatal betamethasone exposure produces gender-specific alternations in renal function and thus suggest that different mechanisms underlie the antenatal steroid-induced elevations in blood pressure in male and female offspring. prenatal steroid exposure; sodium load; glomerular filtration rate; sodium excretion; angiotensin-(1-7)

Egg rejection in birds is a specific adaptation toward avian brood parasitism, whereas nest sanitation is a general behavior for cleaning the nest and avoiding predation. However, both behaviors refer to the action of ejecting objects out of the nest, and nest sanitation has been proposed as a pre-adaptation for egg rejection. Here, we tested the eliciting effect of nest sanitation on egg rejection in the red-whiskered bulbul Pycnonotus jocosus , a potential host species that are sympatric with parasitic cuckoos. We conducted meta-analyses of previous studies on both nest sanitation and egg rejection, in order to evaluate the consistency of our conclusions. Our results showed that nest sanitation did not elicit egg rejection in P. jocosus. The conclusions concerning such an eliciting effect from previous studies were mixed, whereas the methodologies were inconsistent, making the studies unsuitable for comparisons. However, the ejection frequency of nest sanitation was consistently higher than the frequency of egg rejection across different host species or populations. These results suggest that nest sanitation, which is an ancient behavior, is more fundamental than egg rejection, but the effect of the former on the latter is complex and needs further study. Standardized methodologies and the integration of behavior, physiology, and modeling may provide better opportunities to explore the relationship between nest sanitation and egg rejection. [ABSTRACT FROM AUTHOR]

Studies on breeding biology enable us to broaden our understanding of the evolution of life history strategies. We studied the breeding biology of the Green-backed Tit (Parus monticolus) to provide comprehensive data on nest and egg characteristics, parental behavior throughout egg laying and nestling periods, and reproductive outcome. Our study reveals adaptive behavioral patterns and reproductive strategies for P. monticolus. [ABSTRACT FROM AUTHOR]

BACKGROUND Polygonatum sibiricum Liliaceae perennial herb, as a commonly used medicine and food homologous plant, has been widely used in clinical practice of Chinese medicine since ancient times, with a history of 2000 years. As the main active ingredient, P. sibiricum polysaccharides have important pharmacological effects in blood sugar reduction and antitumor, antioxidant and liver protection. RESULTS: Mouse models of P. sibiricum polysaccharides were used in combination with 1H NMR to investigate the metabolic regulation mechanism in mouse tissue and blood. The metabolite maps of the control group and the drug group in the liver had significant changes. The main differential metabolites were glucose 6‐phosphate, inositol, lactose, glutamylglycine, galactose, rhamnose, cis‐aconitic acid and histidine, indicating that there was definite correlation between the metabolic detection based on 1H NMR and the metabolic characteristics of P. sibiricum. The common differential metabolites obtained by overall metabolism analysis were 3‐hydroxybutyric acid, d‐ribose, adenosine phosphate, inositol, fructose 6‐phosphate, histidine, aspartic acid and cis‐aconitic acid. CONCLUSIONS: This work forms the basis for identification of metabolic states combined with metabolic pathways, which could be used as diagnostic and prognostic indicators, providing therapeutic targets for new diseases. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Soluble Triggering Receptor Expressed on Myeloid cells-1(TREM) and Presepsin(PSP) have been shown to differentiate sepsis from inflammation in non-MCS patients. B Introduction: b Infection occurs in up to 32% of children receiving mechanical circulatory support(MCS) with associated increased mortality and is challenging to identify as MCS masks signs of infection and induces an inflammatory response. B Methods: b Prospectively collected plasma samples obtained prior to, and daily for the initial 7 days of MCS from 18 patients with new CX+ infection following initiation of MCS were analyzed to determine levels of TREM, PSP and C-Reactive Protein(CRP). [Extracted from the article]

Antenatal corticosteroid exposure reduces renal function and alters the intrarenal renin-angiotensin system to favor angiotensin activation of angiotensin type 1 receptor (AT1R) mediated responses in ovine offspring. This study aimed to assess whether antenatal steroid exposure would affect renal responses to the direct intrarenal infusion of angiotensin-(1-7) in rams and the angiotensin receptors involved in mediating responses to the peptide. Adult, uninephrectomized rams exposed to either betamethasone or vehicle before birth received intrarenal angiotensin-(1-7) infusions (1 ng/kg/min) alone or in combination with antagonists to angiotensin receptors for 3 h. Basal sodium excretion (UNa) was significantly lower and mean arterial pressure was significantly higher in betamethasone- compared to the vehicle-treated sheep. Angiotensin-(1-7) decreased UNa more in betamethasone- than in vehicle-treated sheep. Candesartan reversed the response to angiotensin-(1-7) but D-Ala(7)-angiotensin-(1-7) did not. Angiotensin-(1-7) infusion decreased effective renal plasma flow in both groups to a similar extent and the response was reversed by candesartan, but was not blocked by D-Ala(7)-angiotensin-(1-7). Glomerular filtration rate increased significantly in both groups after 3 h infusion of angiotensin-(1-7) plus candesartan. These results suggest that antenatal exposure to a clinically relevant dose of betamethasone impairs renal function in rams. Moreover, angiotensin-(1-7) appears capable of activating the AT1R in uninephrectomized rams. [ABSTRACT FROM AUTHOR]

Abstract: A novel nanocomposite material of multiwalled carbon nanotubes (MWCNTs) and room temperature ionic liquid (RTIL) N-butylpyridinium hexafluorophosphate (BPPF6) was explored and used to construct a novel microperoxidase-11 (MP-11) biosensor for the determination of hydrogen peroxide (H2O2). Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to characterize the performance of the biosensor. Under the optimized experimental conditions, H2O2 could be detected in a linear calibration range of 0.5 to 7.0×10−7 molL−1 with a correlation coefficient of 0.9949 (n =9) and a detection limit of 3.8×10−9 molL−1 at 3σ. The modified electrodes displayed excellent electrochemical response, high sensitivity, long-term stability, and good bioactivity and selectivity. [Copyright &y& Elsevier]

Extracorporeal life support provides perfusion for patients with heart failure to allow time for recovery, function as a bridge for patients to heart transplantation, or serve as destination therapy for long term mechanical device support. Several biomarkers have been employed in attempt to predict these outcomes, but it remains to be determined which are suitable to guide clinical practice relevant to extracorporeal life support. Galectin-3 and soluble suppression of tumorigenicity-2 (sST2) are two of the more promising candidates with the greatest supporting evidence. In this review, we address the similarities and differences between galectin-3 and sST2 for prognostic prediction in adults and children with heart failure requiring extracorporeal life support and highlight the significant lack of progress in pediatric biomarker discovery and utilization. [ABSTRACT FROM AUTHOR]

Prenatal exposure to clinically relevant doses of Betamethasone cause a reduction in nephron number in adult sheep, but its effects on renal function are not known. Therefore, we evaluated if prenatal B exposure alters renal function and blood pressure (MAP) during intrarenal infusions of Ang 1-7 (IR A 1-7) with or without its antagonist in adult male sheep. 1.5 year old rams exposed to either Betamethasone (B) or vehicle (C) at 80-81 days gestation received a IR A 1-7 (1ng/kg/min) with or without [D-Ala7]-ANG-(1-7) (D-Ala, 10ng/kg/min) into the renal artery for 24 hours. MAP, GFR, fractional excretion lithium (FE Li) and sodium excretion (UNa) were measured. MAP in B was higher than in C (82.62±3.68 versus 74.99±1.40 mmHg, p<0.01). The infusion did not change MAP and GFR. UNa was lower in B than in C (0.58±0.14 versus 0.33±0.06 meq/h/kg, p<0.05). The IR A 1-7 decreased UNa from 0.58±0.14 meq/h/kg to 0.28±0.04meq/h/kg (p<0.05) in C and from 0.33±0.06 to 0.13±0.03meq/h/kg (p<0.05) in B. FE Li was lower in B than in C (0.21±0.06 vs 0.42±0.08, p<0.05). The data indicate prenatal B exposure increases MAP and impairs renal function including proximal tubular Na reabsorption in adult rams. The IRA 1-7 induced decrease in UNa tended to be greater in C and was not markedly attenuated by D-Ala. The effect of low doses Ang 1-7 may be mediated by a receptor other than the MAS receptor and may be smaller in B. Supported by NIH grants HD 04784 and HD17644 [ABSTRACT FROM AUTHOR]

Background: Cancer patients receiving anthracycline-based chemotherapy (Anth-bC) may experience early cardiac fibrosis, which could be an important contributing mechanism to the development of impaired left ventricular (LV) function. Substance P, a neuropeptide that predominantly acts via the neurokinin 1 receptor (NK-1R), contributes to adverse myocardial remodelling and fibrosis in other cardiomyopathies. We sought to determine if NK-1R blockade is effective against doxorubicin (Dox - a frequently used Anth-bC)-induced cardiac fibrosis and cardiomyocyte apoptosis. In addition, we explored the direct effects of Dox on cardiac fibroblasts.Methods: Male Sprague-Dawley rats were randomised to receive saline, six cycles of Dox (1.5mg Dox/kg/cycle) or Dox with an NK-1R antagonist (L732138, 5mg/kg/daily through Dox treatment). At 8 weeks after the initial dose of Dox, LV function and histopathological myocardial fibrosis and cell apoptosis were assessed. Collagen secretion was measured in vitro to test direct Dox activation of cardiac fibroblasts.Results: Rats undergoing Dox treatment (9mg/kg cumulative dose) developed cardiac fibrosis and cardiomyocyte apoptosis. NK-1R blockade partially mitigated cardiac fibrosis while completely preventing cardiomyocyte apoptosis. This resulted in improved diastolic function. Furthermore, we found that Dox had direct effects on cardiac fibroblasts to cause increased collagen production and enhanced cell survival.Conclusions: This study demonstrates that cardiac fibrosis induced by Anth-bC can be reduced by NK-1R blockade. The residual fibrotic response is likely due to direct Dox effects on cardiac fibroblasts to produce collagen. [ABSTRACT FROM AUTHOR]