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Background: Pogostemon heyneanus leaves infusions are relevant in ethnopharmacology for treating colds, coughs, headaches, and asthma. Purpose: The essential oil chemical composition of a Pogostemon heyneanus specimen was monthly monitored from October 2021 to July 2022 to evaluate the climatic influences on its yield and chemical composition and antinociceptive, andanti-inflammatory properties. Methods: The leaves, collected monthly over a 10-month period, were submitted to hydrodistillation. The oils obtained were analyzed by gas chromatography coupled to a mass spectrometer and gas chromatography coupled to flame ionization detector. The P. heyneanus essential oil (PhEO) was tested in vivo to evaluate its peripheral analgesic actions through the abdominal writhing test induced by acetic acid, and peripheral analgesia by tail immersion. Neurogenic and inflammatory pain were evaluated by formalin test, and acute oral toxicity of the oil was also verified. Results: PhEO presented 27 chemical constituents with the highest predominance of patchoulol (43.6%-76.9%), α-bulnesene (0.2%-12.7%), α-guaiene (0.4%-8.9%), seychellene (3.8%-5.1%) and pogostol (0.0%-8.2%). The climatic parameters insolation, humidity, rainfall, and temperature did not influence the essential oil yield or the main chemical constituents, except for pogostol, which presented a strong (r = 0.73) and statistically significant ( p < 0.05) correlation with temperature. PhEO did not display toxicity at the maximum 300 mg/kg dosage. The oil showed low peripheral and central analgesic action at 100 mg/kg, while in the neurogenic and inflammatory pain inhibition tests, no actions related to PhEO were observed. In the carrageenan-induced peritonitis test, PhEO did not reduce the migration of leukocytes to the peritoneal cavity compared to the control group. Conclusion: Pogostemon heyneanus is a resistant plant to seasonal influences and a source of patchoulol. Despite ethnopharmacological indications, no in-vivo biological activities such as neurogenic or inflammatory pain were identified in the present work. So, the low influence of the climatic parameters on chemical composition can infer that the low pharmacological activity is also not subject to climatic variations, that is, it does not change due to the climate., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Santos, Jerônimo, Ribeiro, Lopes, Leão Neto, da Silva, da Silva, Silva, da Silva, Freitas, Mourão, Setzer, Maia and Figueiredo.)

Objective: To assess the effect of atelectasis during mechanical ventilation on the periatelectatic and normal lung regions in a model of atelectasis in rats with acute lung injury induced by lipopolysaccharide., Methods: Twenty-four rats were randomized into the following four groups, each with 6 animals: the Saline-Control Group, Lipopolysaccharide Control Group, Saline-Atelectasis Group, and Lipopolysaccharide Atelectasis Group. Acute lung injury was induced by intraperitoneal injection of lipopolysaccharide. After 24 hours, atelectasis was induced by bronchial blocking. The animals underwent mechanical ventilation for two hours with protective parameters, and respiratory mechanics were monitored during this period. Thereafter, histologic analyses of two regions of interest, periatelectatic areas and the normally-aerated lung contralateral to the atelectatic areas, were performed., Results: The lung injury score was significantly higher in the Lipopolysaccharide Control Group (0.41 ± 0.13) than in the Saline Control Group (0.15 ± 0.51), p < 0.05. Periatelectatic regions showed higher lung injury scores than normally-aerated regions in both the Saline-Atelectasis (0.44 ± 0.06 x 0.27 ± 0.74 p < 0.05) and Lipopolysaccharide Atelectasis (0.56 ± 0.09 x 0.35 ± 0.04 p < 0.05) Groups. The lung injury score in the periatelectatic regions was higher in the Lipopolysaccharide Atelectasis Group (0.56 ± 0.09) than in the periatelectatic region of the Saline-Atelectasis Group (0.44 ± 0.06), p < 0.05., Conclusion: Atelectasis may cause injury to the surrounding tissue after a period of mechanical ventilation with protective parameters. Its effect was more significant in previously injured lungs.

Introduction: Lactation overnutrition is a programming agent of energy metabolism, and litter size reduction leads to the early development of obesity, which persists until adulthood. Liver metabolism is disrupted by obesity, and increased levels of circulating glucocorticoids are pointed as a possible mediator for the obesity development, since bilateral adrenalectomy (ADX) can reduce obesity in different models of obesity. Methods: This study aimed to evaluate the effects of glucocorticoids on metabolic changes and liver lipogenesis and insulin pathway induced by lactation overnutrition. For this, on the postnatal day 3 (PND), 3 pups (small litter-SL) or 10 pups (normal litter-NL) were kept with each dam. On PND 60, male Wistar rats underwent bilateral adrenalectomy (ADX) or fictitious surgery (sham), and half of ADX animals received corticosterone (CORT- 25 mg/L) diluted in the drinking fluid. On PND 74, the animals were euthanized by decapitation for trunk blood collection, and liver dissection and storage. Results and Discussion: SL rats presented increased corticosterone, free fatty acids, total and LDL-cholesterol plasma levels, without changes in triglycerides (TG) and HDL-cholesterol. The SL group also showed increased content of liver TG, and expression of fatty acid synthase (FASN), but decreased expression of PI3K p110 in the liver, compared to NL rats. In the SL group, the ADX decreased plasma levels of corticosterone, FFA, TG and HDL cholesterol, liver TG, and liver expression of FASN, and IRS2, compared to sham animals. In SL animals, CORT treatment increased plasma levels of TG and HDL cholesterol, liver TG, and expression of FASN, IRS1, and IRS2, compared with the ADX group. In summary, the ADX attenuated plasma and liver changes observed after lactation overnutrition, and CORT treatment could reverse most ADX-induced effects. Thus, increased circulating glucocorticoids are likely to play a pivotal role in liver and plasma impairments induced by lactation overnutrition in male rats., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 de Souza, Stopa, Martins, Wunderlich, Lopes, de Fatima Silva, Komino, Zaia, Zaia, Lima and Uchoa.)

Introduction: breast cancer is the cancer with the highest incidence in women in Brazil, representing 29.7% of all cancers. More than two thirds of women with breast cancer show expression for hormone receptors, and in these cases, hormone therapy with tamoxifen is indicated, which may represent a risk factor for the development of endometrial cancer (four-fold greater relative risk)., Objective: this study aimed to evaluate the association of tamoxifen and the development of endometrial disturbances and to assess possible other associated risk factors., Patients and Method: a total of 364 breast cancer patients were evaluated, 286 who used tamoxifen and 78 who did not use this hormone therapy. Results: patients who used tamoxifen had a mean follow-up time of 51.42 months similar to those without hormone therapy (p=0.081). A total of 21 (7.3%) women who used tamofixen and no cases among women without hormone therapy presented endometrial changes during follow-up (p=0.01). Despite information regarding obesity was available for only 270 women, obesity was also significantly associated with the development of endometrial changes (p=0.008)., Conclusion: furthermore, the association between tamofixen and endometrial changes remained significant (p=0.039) after adjusting for obesity.

Aims: Litter size reduction on the first days of life results in increased body weight and adiposity, with higher levels of circulating glucocorticoids. Obese rodents are more sensitive to the anabolic effects of glucocorticoids and less responsive to glucocorticoids feedback on hypothalamic-pituitary-adrenal (HPA) axis. This study aimed to evaluate effects of the treatment with corticosterone on metabolic responses and HPA axis in adult male rats reared in small litters., Main Methods: From postnatal day (PND) 60 to 88, adult male rats of normal (NL- 10 pups/dam) and small (SL- 3 pups/dam) litters received oral treatment with Corticosterone (CORT-15 mg/L) in the drinking water or no treatment, composing the four experimental groups (NL-water; NL-CORT; SL-water and SL-CORT), for the evaluation of energy homeostasis and HPA axis., Key Findings: Male rats of SL-water group presented on PND88: glucose intolerance, higher adiposity, plasma triglycerides, free fatty acids, total and low-density lipoprotein (LDL) cholesterol and corticosterone. SL-water animals showed increased mRNA of corticotrophin-releasing hormone (CRH) in the hypothalamic paraventricular nucleus (PVN) and proopiomelanocortin (POMC) in the pituitary, with decreased mRNA expression of PVN mineralocorticoid receptor. NL-CORT animals presented glucose intolerance, increased body weight, food intake, total and LDL cholesterol. Glucocorticoid treatment reduced corticosterone levels and adrenal cortex thickness in NL group, associated with increased mRNA of PVN CRH and pituitary POMC, without effects on SL animals., Significance: Lactation overnutrition promotes hyperreactivity of HPA axis and reduces the responsiveness to glucocorticoids effects on energy balance and negative feedback of HPA axis in adult male rats., (Copyright © 2022 Elsevier Inc. All rights reserved.)

This work evaluated the effects of neonatal overfeeding, induced by litter size reduction, on fertility and the noradrenaline-kisspeptin-gonadotrophin releasing hormone (GnRH) pathway in adult female rats. The litter size was adjusted to 3 pups with each mother in the small litters (SL) and 10 pups with each mother in the normal litters (NL). SL females exhibited metabolic changes associated with reproductive dysfunctions, shown by earlier vaginal opening and first estrus, later regular cyclicity onset, and lower and higher occurrences of estrus and diestrus phases, respectively, as well as reduced fertility, estradiol plasma levels, and mRNA expressions of tyrosine hydroxylase in the locus coeruleus, kisspeptin, and GnRH in the preoptic area in adult females in the afternoon of proestrus. These results suggest that neonatal overfeeding in female rats promotes reproductive dysfunctions in adulthood, such as lower estradiol plasma levels associated with impairments in fertility and noradrenaline-kisspeptin-GnRH pathway during positive feedback., (Copyright © 2020 Elsevier B.V. All rights reserved.)

This study aimed at comparatively evaluate, by visual method, the fluorescence intensity in vitro and in vivo of six resins composed of different classifications and viscosities compared to natural enamel. For the in vitro study, seventy specimens were prepared and for the in vivo study, a restoration was performed on the cervical portion of the buccal face of 6 anterior maxillary teeth, which under ultraviolet light were compared to the dental structure. The specimens and restorations were photographed only under the illumination of an ultraviolet lamp. The photographic record was performed, with standardized parameters for all photographs (ISO 100). After visual analysis of the images by three evaluators calibrated in the in vitro study and by ten evaluators calibrated in the in vivo study, numerical values were assigned to resins without fluorescence (zero), medium fluorescence (1) and high fluorescence (2). The evaluations were submitted to the Kruskal-Wallis and Dunn test, which among the limitations of this study and according to the employed methodology, it was found that there was no statistical difference in fluorescence intensity among the composite resins evaluated, since all types of resins achieved fluorescent metamerism with dental enamel., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The effect of low-level laser therapy (LLLT) on an experimental model of ventilator-induced lung injury (VILI) was evaluated in this study. 24 adult Wistar rats were randomized into four groups: protective mechanical ventilation (PMV), PMV + laser, VILI and VILI + laser. The animals of the PMV and VILI groups were ventilated with tidal volumes of 6 and 35 ml kg-1, respectively, for 90 minutes. After the first 60 minutes of ventilation, the animals in the laser groups were irradiated (808 nm, 100 mW power density, 20 J cm-2 energy density, continuous emission mode, and exposure time of 5 s) and after 30 minutes of irradiation, the animals were euthanized. Lung samples were removed for morphological analysis, bronchoalveolar lavage (BAL) and real time quantitative polynucleotide chain reaction (RT-qPCR). The VILI group showed a greater acute lung injury (ALI) score with an increase in neutrophil infiltration, higher neutrophil count in the BAL fluid and greater cytokine mRNA expression compared to the PMV groups (p < 0.05). The VILI + laser group when compared to the VILI group showed a lower ALI score (0.35 ± 0.08 vs. 0.54 ± 0.13, p < 0.05), alveolar neutrophil infiltration (7.00 ± 5.73 vs. 21.50 ± 9.52, p < 0.05), total cell count (1.90 ± 0.71 vs. 4.09 ± 0.96 × 105, p < 0.05) and neutrophil count in the BAL fluid (0.60 ± 0.37 vs. 2.28 ± 0.48 × 105, p < 0.05). Moreover, LLLT induced a decrease in pro-inflammatory and an increase of anti-inflammatory mRNA levels compared to the VILI group (p < 0.05). In conclusion, LLLT was found to reduce the inflammatory response in an experimental model of VILI.

Although anthracycline (ANT)-based treatment strongly contributes to cancer survivorship, the use of these agents is limited by the risk of cardiotoxicity. For those patients who evolve to heart failure, myocardial regenerative approaches are of particular interest, and a growing body of preclinical studies has been investigating the use of cell therapy for ANT-induced cardiomyopathy (AIC). However, since animal models and modalities of cell therapy are highly heterogeneous between studies, the efficacy of cell therapy for AIC is not clear. Thus, we conducted a systematic review and meta-analysis of experimental studies reporting the use of cell therapy with mesenchymal stromal cells (MSC) or bone marrow mononuclear cells (BMMNC) in animal models of AIC with regard to global cardiac function. The Medline, EMBASE, and Web of Science databases were searched from inception to November 2019. Two reviewers independently extracted data on study quality and the results of left ventricular ejection fraction (LVEF) and fractional shortening (FS) obtained by echocardiography. The quality of outcomes was assessed using the Cochrane, Collaborative Approach to Meta-Analysis and Review of Animal Data from Experimental Studies (CAMARADES), and SYRCLE bias risk tools. Pooled random-effects modeling was used to calculate pooled mean differences (MD) and 95% confidence intervals (CIs). Twenty-two studies comprising 381 small animals (rabbits and rodents) were included. A pooled meta-analysis of all treatments showed that cell therapy increased LVEF by 9.87% (95% CI 7.25-12.50, P  < 0.00001) and FS by 7.80% (95% CI 5.68-9.92, P  < 0.00001) in small animals with AIC. Cell therapy with MSC/BMMNC is effective to mitigate the deleterious effects of ANT on cardiac function in preclinical models. Nevertheless, due to the small number of studies and considerable heterogeneity, future translational studies must be designed to diminish between-study discrepancies and increase similarity to the clinical landscape.

Overpopulation and environmental degradation due to inadequate resource-use are outcomes of human's ecosystem engineering that has profoundly modified the world's landscape. Despite the age-old concern that unchecked population and economic growth may be unsustainable, the prospect of societal collapse remains contentious today. Contrasting with the usual approach to modeling human-nature interactions, which are based on the Lotka-Volterra predator-prey model with humans as the predators and nature as the prey, here we address this issue using a discrete-time population dynamics model of ecosystem engineers. The growth of the population of engineers is modeled by the Beverton-Holt equation with a density-dependent carrying capacity that is proportional to the number of usable habitats. These habitats (e.g., farms) are the products of the work of the individuals on the virgin habitats (e.g., native forests), hence the denomination engineers of ecosystems to those agents. The human-made habitats decay into degraded habitats, which eventually regenerate into virgin habitats. For slow regeneration resources, we find that the dynamics is dominated by rounds of prosperity and collapse, in which the population reaches vanishing small densities. However, increase of the efficiency of the engineers to explore the resources eliminates the dangerous oscillatory patterns of feast and famine and leads to a stable equilibrium that balances population growth and resource availability. This finding supports the viewpoint of growth optimists that technological progress may avoid collapse.