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Ontogenetic sexual dimorphism is observed in different primate species, with ecological and evolutionary relationships explaining this pattern. Understanding the growth of the southern brown howler monkey elucidates not only the ecology and evolution but also contributes to conservation projects for this species. Throughout 20 years of the Centro de Pesquisas Biológicas de Indaial-Projeto Bugio, Brazil, we collected morphological data on 105 howlers of the Alouatta guariba species to identify the growth differences between ontogenetic categories and sexes and generate a growth curve to estimate the age of rescued individuals. Linear measurements were employed to obtain body length as well as the dimensions of the head and limbs. All individuals were also weighed to obtain body mass. We assessed growth rate and duration using allometric analysis based on the individuals' ages. We compared growth rate and duration among infant, juvenile, and adult howlers and between sexes. We provide growth curves for body size for both sexes using the Von Bertalanffy model. Infants have accelerated growth rate in comparison to the juveniles and adults, with no differences between sexes in establishing body length at this ontogenetic stage. Males have a prolonged development duration from the juvenile stage, reaching adulthood later than females, which explains the body length differences found in this species. Variables of head and limbs analyzed also showed differences in growth rate and duration, but not so consistently among ontogenetic stages. Mass was not a good variable to understand the growth differences of the animals, since many arrived feeble in the project and may have lost mass due to different circumstances in old age. Therefore, growth curves were obtained only for body length, allowing the estimation of the age of these animals when rescued from the wild to more effectively provide needed care in captivity.
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Alouatta , Tamanho Corporal , Animais , Alouatta/anatomia & histologia , Alouatta/crescimento & desenvolvimento , Alouatta/fisiologia , Masculino , Feminino , Brasil , Conservação dos Recursos Naturais , Caracteres SexuaisRESUMO
Variations in the size of animals of the same species but of different sex are called sexual size dimorphism. The aim of this study was to compare the biometrics between males and females of the Sanmartinero creole bovine, of Colombia, to establish if sexual dimorphism appears in the breed. A total of 94 animals (16 uncastrated males and 78 females, average age of 4.3 ± 1.4 and 4.2 ± 2.3 years, respectively) from three different farms were measured. A total of 21 linear variables were obtained using standard morphometric methods and live weight. A one-way NPMANOVA was used to evaluate between sexes, ages, and farms, a Principal Component Analysis was used to detect the most discriminating variables, and a multivariate regression used age as an independent value. Statistically significant differences were reflected between sexes (p = 0.033) and not by age and farms. The variables that differentiated the most between males and females were those related to size (thoracic circumference, body length, dorso-sternal diameter, height at the withers, height at the rump, and horn length), variables that were biased toward males, although only the height at the withers and the rump were the ones that presented statistically significant differences.
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Methylphenidate (MPH) is a central nervous system stimulant drug and a first order prescription in the treatment of Attention Deficit Hyperactivity Disorder (ADHD). Although MPH biochemistry in neurodevelopment is not completely understood, studies showed it alters energy metabolism in rat brains. ADHD prevalence during neurodevelopment is related to males and the investigation has been mainly done in these subjects, therefore, little is known about MPH action in females and, consequently, about sexual dimorphism. In the present study we evaluated markers of mitochondrial dynamics (DRP1 and MFN2, fission and fusion, respectively), biogenesis (mtTFA) and bioenergetics (respiratory chain complexes) in prefrontal cortex of male and female juvenile rats submitted to exposure to MPH to better understand MPH effect during postnatal neurodevelopment. ATP and oxidative stress levels were also evaluated. Wistar rats received intraperitoneal injection of MPH (2.0 mg/kg) or control (saline), once a day, from 15th to 45th day of age. Results showed that MPH increased DRP1 and decreased MFN2, as well as increased mtTFA in prefrontal cortex of male rats. In female, MPH decreased NRF1 and increased Parkin, which are mitochondrial regulatory proteins. Respiratory chain complexes (complex I, SDH, complexes III and IV), ATP production and oxidative stress parameters were altered and shown to be sex-dependent. Taken together, results suggest that chronic MPH exposure at an early age in healthy animals changes mitochondrial dynamics, biogenesis and bioenergetics differently depending on the sex of the subjects.
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Estimulantes do Sistema Nervoso Central , Dinaminas , Metabolismo Energético , Metilfenidato , Dinâmica Mitocondrial , Estresse Oxidativo , Córtex Pré-Frontal , Ratos Wistar , Animais , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Metilfenidato/farmacologia , Masculino , Dinâmica Mitocondrial/efeitos dos fármacos , Feminino , Estimulantes do Sistema Nervoso Central/farmacologia , Metabolismo Energético/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Dinaminas/metabolismo , Ratos , Caracteres Sexuais , Trifosfato de Adenosina/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas Mitocondriais , Ubiquitina-Proteína LigasesRESUMO
Several studies have evaluated the parameters of normality of the sella turcica (ST), which is important to face different craniofacial syndromes that may affect this structure. Therefore, this research summarized the scientific evidence on the role of ST in the sex estimation of non-syndromic individuals. The research protocol was registered (Prospective International Registry of Systematic Reviews # CRD42021256469), followed by an electronic search in six databases (PubMed, LILACS, Web of Science, Scopus, EMBASE, and LIVIVO) and gray literature (Google Scholar and OpenGrey). Meta-analysis of linear (width, length, height, and diameter) and volumetric measurements, in addition to an assessment of risk of bias (RoB) and certainty of evidence, were performed. After the screening of 986 articles, 13 were evaluated by meta-analysis (1 307 males and 1 231 females). In subgroup analysis, females had lower values for width (lateral radiograph; -0.67 mm; P = 0.040), length (computed tomography; -0.23 mm; P = 0.020), and diameter (computed tomography; -0.27 mm; P < 0.001) compared to males. There was no statistically significant difference regarding height (P = 0.95), area (P = 0.72), and volume (P = 0.21). Most studies exhibited moderate RoB, and the certainty of evidence of the outcomes was very low. In this review, significant differences were observed between the sexes for the length and diameter of the ST; however, the heterogeneity of the studies must be considered. Key points: Studies from different geographic regions evaluated the morphology of ST according to sex and showed this anatomical structure as an important indicator of dimorphism.Meta-analysis showed shorter ST length and diameter in women.Subgroup analysis found lower ST width in women based on lateral skull radiographs.Subgroup analysis found smaller lengths and diameters in women based on CT scans.
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Background: Chronic cerebral hypoperfusion (CCH) leads to memory and learning impairments associated with degeneration and gliosis in the hippocampus. Treatment with physical exercise carries different therapeutic benefits for each sex. We investigated the effects of acrobatic training on astrocyte remodeling in the CA1 and CA3 subfields of the hippocampus and spatial memory impairment in male and female rats at different stages of the two-vessel occlusion (2VO) model. Methods: Wistar rats were randomly allocated into four groups of males and females: 2VO acrobatic, 2VO sedentary, sham acrobatic, and sham sedentary. The acrobatic training was performed for 4 weeks prior to the 2VO procedure. Brain samples were collected for morphological and biochemical analysis at 3 and 7 days after 2VO. The dorsal hippocampi were removed and prepared for Western blot quantification of Akt, p-Akt, COX IV, cleaved caspase-3, PARP, and GFAP. GFAP immunofluorescence was performed on slices of the hippocampus to count astrocytes and apply the Sholl's circle technique. The Morris water maze was run after 45 days of 2VO. Results: Acutely, the trained female rats showed increased PARP expression, and the 2VO-trained rats of both sexes presented increased GFAP levels in Western blot. Training, mainly in males, induced an increase in the number of astrocytes in the CA1 subfield. The 2VO rats presented branched astrocytes, while acrobatic training prevented branching. However, the 2VO-induced spatial memory impairment was partially prevented by the acrobatic training. Conclusion: Acrobatic training restricted the astrocytic remodeling caused by 2VO in the CA1 and CA3 subfields of the hippocampus. The improvement in spatial memory was associated with more organized glial scarring in the trained rats and better cell viability observed in females.
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MafB is a transcription factor that regulates macrophage differentiation. Macrophages are a traditional feature of the hamster Harderian gland (HG); however, studies pertaining to MafB expression in the HG are scant. Here, the full-length cDNA of the MafB gene in hamsters was cloned and sequenced. Molecular characterization revealed that MafB encodes a protein containing 323 amino acids with a DNA-binding domain, a transactivation domain, and a leucine zipper domain. qPCR assays indicated that MafB was expressed in different tissues of both sexes. The highest relative expression levels in endocrine tissues were identified in the pancreas. Gonadectomy in male hamsters was associated with significantly higher mRNA levels in the HG; replacement with dihydrotestosterone restored mRNA expression. The HG in male hamsters contained twofold more MafB mRNA than the HG of female hamsters. Adrenals revealed similar mRNA relative expression levels during the estrous cycle. The estrous phase was associated with higher mRNA levels in the ovary. A significantly up-regulated expression and sexual dimorphism of MafB was found in the pancreas. Therefore, MafB in the HG may play an active role in the macrophage differentiation required for phagocytosis activity and intraocular repair. Additionally, sex steroids appear to strongly influence the MafB expression in the HG and pancreas. These studies highlight the probable biological importance of MafB in immunological defense and pancreatic ß cell regulation.
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BACKGROUND: Expansion of genomic resources for the Pacific white shrimp (Litopenaeus vannamei), such as the construction of dense genetic linkage maps, is crucial for the application of genomic tools in order to improve economically relevant traits. Sexual dimorphism exists in Pacific white shrimp, and the mapping of the sex-determination region in this species may help in future reproductive applications. We have constructed male, female, and sex-averaged high-density genetic maps using a 50 K single-nucleotide polymorphism (SNP) array, followed by a genome-wide association study (GWAS) to identify genomic regions associated with sex in white shrimp. RESULTS: The genetic map yielded 15,256 SNPs assigned to 44 linkage groups (LG). The lengths of the male, female, and sex-averaged maps were 5,741.36, 5,461.20 and 5,525.26 cM, respectively. LG18 was found to be the largest for both sexes, whereas LG44 was the shortest for males and LG31 for females. A sex-determining region was found in LG31 with 21 statistically significant SNPs. The most important SNP was previously identified as a sex-linked marker and was able to identify 99% of the males and 88% of the females. Although other significant markers had a lower ability to determine sex, putative genes were intercepted or close to them. The oplophorus-luciferin 2-monooxygenase, serine/arginine repetitive matrix protein and spermine oxidase genes were identified as candidates with possible participation in important processes of sexual differentiation in shrimp. CONCLUSIONS: Our results provide novel genomic resources for shrimp, including a high-density linkage map and new insights into the sex-determining region in L. vannamei, which may be usefulfor future genetics and reproduction applications.
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Mapeamento Cromossômico , Penaeidae , Polimorfismo de Nucleotídeo Único , Processos de Determinação Sexual , Animais , Penaeidae/genética , Feminino , Masculino , Processos de Determinação Sexual/genética , Ligação Genética , Estudo de Associação Genômica AmplaRESUMO
Objective: This study aims to evaluate the sexual dimorphism of maxillary sinuses (MS) using cone-beam computed tomography (CBCT). Method: A total of 80 CBCT scans were taken from Peruvian patients aged between 20 and 70 years-old. The dimensions (length, width, and height) of the MS were measured and evaluated. The data were analyzed using the Mann-Whitney U test with a significance level of p < 0.05. Results: The left MS was wider than the right MS. Meanwhile, the right MS was longer than the left MS. In addition, the height of the right and left MS was significantly different in males and females, with p-value of 0.003 and 0.044 respectively. Bigger dimension of height of the MS was found in patients aged between 30 and 39 as well as patients aged between 40 and 49, whereas smaller dimension of height of the MS was found in patients aged between 60 and 70. Furthermore, the height of the right MS was significantly different in dentate and edentulous patients, with p-value of 0.033 and 0.043 respectively. The height of the right MS was predicted at 65 % in males and 70 % in females (p = 0.002). Conclusion: The morphometry of the maxillary sinuses can be used for predicting sexual dimorphism.
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Chile had a violent military coup (1973-1990) that resulted in 3,000 victims declared detained, missing or killed; many are still missing and unidentified. Currently, the Human Rights Unit of the Forensic Medical Service in Chile applies globally recognised forensic anthropological approaches, but many of these methods have not been validated in a Chilean sample. As current research has demonstrated population-specificity with extant methods, the present study aims to validate sex estimation methods in a Chilean population and thereafter establish population-specific equations. A sample of 265 os coxae of known age and sex of adult Chileans from the Santiago Subactual Osteology Collection were analysed. Visual assessment and scoring of the pelvic traits were performed in accordance with the Phenice (1969) and Klales et al. (2012) methods. The accuracy of Phenice (1969) in the Chilean sample was 96.98%, with a sex bias of 7.68%. Klales et al. (2012) achieved 87.17% accuracy with a sex bias of -15.39%. Although both methods showed acceptable classification accuracy, the associated sex bias values are unacceptable in forensic practice. Therefore, six univariate and eight multivariate predictive models were formulated for the Chilean population. The most accurate univariate model was the ventral arc at 96.6%, with a sex bias of 5.2%. Classification accuracy using all traits was 97.0%, with a sex bias of 7.7%. This study provides Chilean practitioners a population-specific morphoscopic standard with associated classification probabilities acceptable to accomplish legal admissibility requirements in human rights and criminal cases specific to the second half of the 20th century.
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Antropologia Forense , Determinação do Sexo pelo Esqueleto , Humanos , Chile , Determinação do Sexo pelo Esqueleto/métodos , Masculino , Feminino , Antropologia Forense/métodos , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Idoso , Ossos Pélvicos/anatomia & histologia , Osso Púbico/anatomia & histologiaRESUMO
Recent studies have shown that maternal vitamin D deficiency (VDD) causes long-term metabolic changes in offspring. However, little is known about the impact of maternal VDD on offspring endocrine pancreas development and insulin secretion in the adult life of male and female animals. Female rats (Wistar Hannover) were fed either control (1000 IU Vitamin D3/kg), VDD (0 IU Vitamin D3/kg), or a Ca2+-enriched VDD diet (0 IU Vitamin D3/kg + Ca2+ and P/kg) for 6 weeks and during gestation and lactation. At weaning, VDD status was confirmed based on low serum calcidiol levels in dams and pups. Next, male and female offspring were randomly separated and fed a standard diet for up to 90 days. At this age, serum calcidiol levels were restored to normal levels in all groups, but serum insulin levels were decreased in VDD males without affecting glucagon levels, glycemia, or glucose tolerance. Islets isolated from VDD males showed lower insulin secretion in response to different glucose concentrations, but this effect was not observed in VDD females. Furthermore, VDD males, but not females, showed a smaller total pancreatic islet area and lower ß cell mass, an effect that was accompanied by reduced gene expression of Ins1, Ins2, Pdx1, and SLC2A2. The decrease in Pdx1 expression was not related to the methylation profile of the promoter region of this gene. Most of these effects were observed in the male VDD+Ca2+ group, indicating that the effects were not due to alterations in Ca2+ metabolism. These data show that maternal VDD selectively impairs the morphology and function of ß cells in adult male offspring rats and that female offspring are fully protected from these deleterious effects.
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Células Secretoras de Insulina , Insulina , Ratos Wistar , Deficiência de Vitamina D , Animais , Feminino , Células Secretoras de Insulina/metabolismo , Masculino , Deficiência de Vitamina D/metabolismo , Ratos , Gravidez , Insulina/sangue , Insulina/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/etiologia , Fatores Sexuais , Secreção de InsulinaRESUMO
Thyroid disorders affect more women than men, but the underlying mechanisms contributing to this disparity remain incompletely understood. Thyrotropin (TSH), the primary regulator of thyroid oxidative hormonogenesis, has been implicated as a risk factor for proliferative thyroid diseases and a predictor of malignancy. In this study, we aimed to evaluate the impact of sustained elevated TSH levels on thyroid redox homeostasis, inflammatory markers, and DNA damage response in both male and female rats. Rats were treated with methimazole for 7 or 21 days, and hormonal measurements were conducted. H2O2 levels were evaluated in thyroid membrane fractions, while enzymatic activities were assessed in total thyroid homogenates. Sex-specific differences emerged, with females displaying higher reactive oxygen species levels - increased transiently NOX and sustained DUOX activities. Lipid peroxidation marker 4-hydroxynonenal (4-HNE) was elevated in females at both time points, contrasting with males just at 21 days. Sexual dimorphism was observed in DNA damage response, with females showing higher γH2AX levels at 21 days. Elevated IL-1ß, TNF-α, CD11b mRNA, and phospho-NF-κB levels at 7 days indicated a distinct inflammatory profile in females. Notably, both sexes exhibited upregulated antioxidant enzymes. Our data suggest that females are more susceptible to oxidative damage and inflammation in our goiter model, which may be associated with higher ROS production and a less-efficient antioxidant defense system. These findings provide insights into the sex-specific mechanisms underlying thyroid dysfunction and highlight the importance of considering sex disparities in thyroid disorder research.
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Antioxidantes , Bócio , Ratos , Feminino , Masculino , Humanos , Animais , Antioxidantes/metabolismo , Peróxido de Hidrogênio , Estresse Oxidativo , Tireotropina , InflamaçãoRESUMO
This study examined the impact of maternal protein supplementation during mid-gestation on offspring, considering potential sex-related effects. Forty-three pregnant purebred Tabapuã beef cows (20 female and 23 male fetuses) were collectively managed in a pasture until 100 d of gestation. From 100 to 200 d of gestation, they were randomly assigned to the restricted group [(RES) - basal diet (75% corn silageâ +â 25% sugar cane bagasseâ +â mineral mixture); nâ =â 24] or control group [(CON) - same basal dietâ +â based-plant supplement [40% of crude protein, 3.5 g/kg of body weight (BW); nâ =â 19]. From 200 d of gestation until parturition, all cows were equally fed corn silage and mineral mixture. During the cow-calf phase, cows and their calves were maintained in a pasture area. After weaning, calves were individually housed and evaluated during the backgrounding (255 to 320 d), growing 1 (321 to 381 d), and growing 2 (382 to 445 d) phases. Offspring's blood samples were collected at 210 and 445 d of age. Samples of skeletal muscle tissue were collected through biopsies at 7, 30, and 445 d of age. Muscle tissue samples were subjected to reverse-transcription quantitative polymerase chain reaction analysis. Prenatal treatment and offspring's sex (when pertinent) were considered fixed effects. The significance level was set at 5%. At mid-gestation, cows supplemented with protein reached 98% and 92% of their protein and energy requirements, while nonsupplemented cows attained only 30% and 50% of these requirements, respectively. The RES offspring were lighter at birth (27 vs. 31 kg), weaning (197 vs. 214 kg), and 445 d of age (398 vs. 429 kg) (Pâ ≤â 0.05). The CON calves had greater (Pâ <â 0.05) morphometric measurements overall. The CON offspring had ~26% greater muscle fiber area (Pâ ≤â 0.01). There was a trend (Pâ =â 0.06) for a greater Mechanistic target of rapamycin kinase mRNA expression in the Longissimus thoracis in the CON group at 7 d of age. The Myogenic differentiation 1 expression was greater (Pâ =â 0.02) in RES-females. Upregulation of Carnitine palmitoyltransferase 2 was observed in RES offspring at 445 d (Pâ =â 0.04). Expression of Fatty acid binding protein 4 (Pâ <â 0.001), Peroxisome proliferator-activated receptor gamma (Pâ <â 0.001), and Stearoyl-Coenzyme A desaturase (Pâ <â 0.001) was upregulated in CON-females. Therefore, protein supplementation during gestation enhances offspring growth and promotes favorable responses to lipogenesis, particularly in females.
In tropical conditions, beef cows on pasture often experience protein restriction during mid-to-late gestation, potentially impacting offspring development negatively. To address this, we investigated the effects of strategic protein supplementation for pregnant beef cows fed low-quality forage during mid-gestation on the postnatal growth trajectory of their offspring. The supplementation program, implemented during mid-gestation, increased dry matter intake by addressing nitrogen deficiency in the rumen, resulting in meeting 98% and 92% of protein and energy requirements in supplemented cows. In contrast, nonsupplemented cows met only 30% and 50% of these requirements, respectively. Consequently, protein supplementation positively influenced the postnatal growth trajectory of the offspring, attributed to beneficial changes in secondary myogenesis and hypertrophy processes. Supplementing cows with crude protein also stimulated lipogenesis, potentially contributing to intramuscular fat deposition, particularly in females. Therefore, this study emphasizes the importance of nutritional interventions for pregnant beef cows fed low-quality forage.
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Ração Animal , Suplementos Nutricionais , Animais , Bovinos , Feminino , Gravidez , Ração Animal/análise , Dieta/veterinária , Suplementos Nutricionais/análise , Minerais , Músculo Esquelético , MasculinoRESUMO
Harvestmen are a major arachnid order that has experienced a dramatic increase in biological knowledge in the 21st century. The publication of the book Harvestmen: The Biology of Opiliones in 2007 stimulated the development of many behavioral studies. Although the book is relatively recent, our understanding of the reproductive biology of harvestmen is already outdated due to the fast accumulation of new data. Our goal is to provide an updated review of the subject to serve as a benchmark for the following years. In the pre-copulatory phase, we explore the evolution of facultative parthenogenesis, the factors that may affect the types of mating system, and the role of nuptial gifts in courtship. Regarding the copulatory phase, harvestmen are unique arachnids because they have aflagellate spermatozoa and a penis with complex morphology. We discuss the implications of these two features for sperm competition and cryptic female choice. In the post-copulatory phase, we connect oviposition site selection and climate conditions to the widespread occurrence of resource defense polygyny, alternative reproductive tactics, and sexual dimorphism in several clades of tropical harvestmen. Finally, we present the different forms of parental care in the order, and discuss the benefits and costs of this behavior, which can be performed either by females or males. Throughout the review, we indicate gaps in our knowledge and subjects that deserve further studies. Hopefully, the information synthesized here will stimulate researchers worldwide to embrace harvestmen as a study system and to improve our effort to unravel the mysteries of their reproductive biology.
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Argyrotaeniasocoromaensissp. nov. (Lepidoptera, Tortricidae, Tortricinae, Archipini) from the arid Andes of northern Chile is described and illustrated. Adults are sexually dimorphic, with differences in wing size, shape and pattern. The larvae feed on Steviaphilippiana Hieron. (Asteraceae) and Lupinusoreophilus Phil. (Fabaceae). Genetic distance between DNA barcodes of male and female adults reared from larvae collected on the two hosts was 0-0.2% (K2P). The discovery of A.socoromaensissp. nov. represents the first record of the genus Argyrotaenia Stephens, 1852 and the tribe Archipini for the Chilean fauna of Tortricidae.
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The converse Bergmann's rule is a pattern of body size variation observed in many ectothermic organisms that contradicts the classic Bergmann's rule and suggests that individuals inhabiting warmer climates tend to exhibit larger body sizes compared to those inhabiting colder environments. Due to the thermoregulatory nature of Bergmann's rule, its application among ectotherms might prove to be more complicated, given that these organisms obtain heat by absorbing it from their habitat. The existence of this inverse pattern therefore challenges the prevailing notion that larger body size is universally advantageous in colder climates. Ceroglossus chilensis is a native Chilean beetle that has the largest latitudinal range of any species in the genus, from 34.3° S to 47.8° S. Within Chile, it continuously inhabits regions extending from Maule to Aysen, thriving on both native and non-native forest species. Beyond their remarkable color variation, populations of C. chilensis show minimal morphological disparity, noticeable only through advanced morphological techniques (geometric morphometrics). Based on both (1) the "temperature-size rule", which suggests that body size decreases with increasing temperature, and (2) the reduced resource availability in high-latitude environments that may lead to smaller body sizes, we predict that C. chilensis populations will follow the converse Bergmann's rule. Our results show a clear converse pattern to the normal Bergmann rule, where smaller centroid sizes were found to be measured in the specimens inhabiting the southern areas of Chile. Understanding the prevalence of the converse Bergmann's rule for ectotherm animals and how often this rule is broken is of utmost importance to understand the underlying mechanisms allowing organisms to adapt to different environments and the selective pressures they face.
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OBJECTIVES: Comparisons between Indigenous peoples over time and within a particular geographic region can shed light on the impact of environmental transitions on the skeleton, including relative bone strength, sexual dimorphism, and age-related changes. Here we compare long bone structural properties of the inhabitants of the late prehistoric-early historic Pecos Pueblo with those of present-day Indigenous individuals from New Mexico. MATERIALS AND METHODS: Femora and tibiae of 126 adults from Pecos Pueblo and 226 present-day adults were included in the study. Cross-sectional diaphyseal properties-areas and second moments of area-were obtained from past studies of the Pecos Pueblo skeletal sample, and from computed tomography scans of recently deceased individuals in the present-day sample. RESULTS: Femora and tibiae from Pecos individuals are stronger relative to body size than those of present-day Indigenous individuals. Present-day individuals are taller but not wider, and this body shape difference affects cross-sectional shape, more strongly proximally. The tibia shows anteroposterior strengthening among Pecos individuals, especially among males. Sexual dimorphism in midshaft bone shape is stronger within the Pecos Pueblo sample. With aging, Pecos individuals show more medullary expansion but also more subperiosteal expansion than present-day individuals, maintaining bone strength despite cortical thinning. DISCUSSION: Higher activity levels, carried out over rough terrain and throughout adult life, likely explain the relatively stronger lower limb bones of the Pecos individuals, as well as their greater subperiosteal expansion with aging. Greater sexual dimorphism in bone structure among Pecos individuals potentially reflects greater gender-based differences in behavioral patterns.
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Fêmur , Tíbia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Antropologia Física , Fêmur/anatomia & histologia , Fêmur/diagnóstico por imagem , História Antiga , Indígenas Norte-Americanos/história , Povos Indígenas/história , Desenvolvimento Industrial/história , New Mexico , Tíbia/anatomia & histologia , Tíbia/diagnóstico por imagemRESUMO
Growth hormone (GH) modifies liver gene transcription in a sexually dimorphic manner to meet liver metabolic demands related to sex; thus, GH dysregulation leads to sex-biased hepatic disease. We dissected the steps of the GH regulatory cascade modifying GH-dependent genes involved in metabolism, focusing on the male-predominant genes Lcn13, Asns, and Cyp7b1, and the female-predominant genes Hao2, Pgc1a, Hamp2, Cyp2a4, and Cyp2b9. We explored mRNA expression in 2 settings: (i) intact liver GH receptor (GHR) but altered GH and insulin-like growth factor 1 (IGF1) levels (NeuroDrd2KO, HiGH, aHepIGF1kd, and STAT5bCA mouse lines); and (ii) liver loss of GHR, with or without STAT5b reconstitution (aHepGHRkd, and aHepGHRkd + STAT5bCA). Lcn13 was downregulated in males in most models, while Asns and Cyp7b1 were decreased in males by low GH levels or action, or constant GH levels, but unexpectedly upregulated in both sexes by the loss of liver Igf1 or constitutive Stat5b expression. Hao, Cyp2a4, and Cyp2b9 were generally decreased in female mice with low GH levels or action (NeuroDrd2KO and/or aHepGHRkd mice) and increased in HiGH females, while in contrast, Pgc1a was increased in female NeuroDrd2KO but decreased in STAT5bCA and aHepIGF1kd females. Bioinformatic analysis of RNAseq from aHepGHRkd livers stressed the greater impact of GHR loss on wide gene expression in males and highlighted that GH modifies almost completely different gene signatures in each sex. Concordantly, we show that altering different steps of the GH cascade in the liver modified liver expression of Lcn13, Asns, Cyp7b1, Hao2, Hamp2, Pgc1a, Cyp2a4, and Cyp2b9 in a sex- and gene-specific manner.
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Disruption of the brain serotoninergic (5-HT) system during development induces long-lasting changes in molecular profile, cytoarchitecture, and function of neurons, impacting behavioral regulation throughout life. In male and female rats, we investigate the effect of neonatal tryptophan hydroxylase (TPH) inhibition by using para-chlorophenylalanine (pCPA) on the expression of 5-HTergic system components and neuropeptides related to adolescent social play behavior regulation. We observed sex-dependent 5-HT levels decrease after pCPA-treatment in the dorsal raphe nucleus (DRN) at 17 and 35 days. Neonatal pCPA-treatment increased playing, social and locomotory behaviors assessed in adolescent rats of both sexes. The pCPA-treated rats demonstrated decreased Crh (17 days) and increased Trh (35 days) expression in the hypothalamic paraventricular nucleus (PVN). There was sex dimorphism in Htr2c (17 days) and VGF (35 days) in the prefrontal cortex, with the females expressing higher levels of it than males. Our results indicate that neonatal pCPA-treatment results in a long-lasting and sex-dependent DRN 5-HT synthesis changes, decreased Crh, and increased Trh expression in the PVN, resulting in a hyperactivity-like phenotype during adolescence. The present work demonstrates that the impairment of TPH function leads to neurobehavioral disorders related to hyperactivity and impulsivity, such as attention deficit hyperactivity disorder (ADHD).
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Núcleo Hipotalâmico Paraventricular , Serotonina , Ratos , Feminino , Masculino , Animais , Fenclonina/farmacologia , Núcleo Hipotalâmico Paraventricular/metabolismo , Serotonina/metabolismo , Núcleo Dorsal da Rafe/metabolismo , Triptofano Hidroxilase/metabolismoRESUMO
Dehydration is a stress factor for organisms inhabiting natural habitats where water is scarce. Thus, it may be expected that species facing arid environments will develop mechanisms that maximize resistance to desiccation. Insects are excellent models for studying the effects of dehydration as well as the mechanisms and processes that prevent water loss since the effect of desiccation is greater due to the higher area/volume ratio than larger animals. Even though physiological and behavioral mechanisms to cope with desiccation are being understood, the genetic basis underlying the mechanisms related to variation in desiccation resistance and the context-dependent effect remain unsolved. Here we analyze the genetic bases of desiccation resistance in Drosophila melanogaster and identify candidate genes that underlie trait variation. Our quantitative genetic analysis of desiccation resistance revealed sexual dimorphism and extensive genetic variation. The phenotype-genotype association analyses (GWAS) identified 71 candidate genes responsible for total phenotypic variation in desiccation resistance. Half of these candidate genes were sex-specific suggesting that the genetic architecture underlying this adaptive trait differs between males and females. Moreover, the public availability of desiccation data analyzed on the same lines but in a different lab allows us to investigate the reliability and repeatability of results obtained in independent screens. Our survey indicates a pervasive micro-environment lab-dependent effect since we did not detect overlap in the sets of genes affecting desiccation resistance identified between labs.