Sex Differences Research Articles

Intrinsic sex differences in fibrous atherosclerotic plaques

Intrinsic sex differences in fibrous atherosclerotic plaques

Behavioral Training in First-Generation Long-Tailed Macaques (Macaca fascicularis) for Improved Husbandry and Veterinary Procedures.

Owing to their similarities to humans in various aspects, non-human primates (NHPs) serve as valuable translational models that has greatly contributed to scientific advancements. However, working with untrained NHPs can cause stress and increase the risk of injuries to both animals and care staff, compromising both animal welfare and occupational safety. Behavioral training, that benefits from animals' learning abilities to gain their cooperation during husbandry and veterinary procedures, is a well-established method to mitigate these risks. Cynomolgus monkeys, in particular, are known for being despotic, fearful, and challenging to train. Moreover, our first-generation breeders were wild-sourced from human-macaque conflict areas in Thailand. These macaque populations are accustomed with human contact; hence, their prior experience can either work for or against behavioral shaping plans. Establishing a training program with realistic expectations would benefit both the animals and trainers. In this study, six cynomolgus monkeys were selected based on temperament, then underwent a pilot training program that included basic husbandry and veterinary procedures. Over 256 training sessions with gradual shaping plans, all six monkeys went through all training steps, with progress varying considerably among individuals. Cortisol levels were measured to monitor stress responses, revealing a notable sex difference: female monkeys generally complied more easily with the trainer but exhibited a stronger cortisol increase compared to males. This study proposed a behavioral training program grounded in three essential components: temperament assessment, behavioral shaping plans, and the cortisol-based criteria for evaluating training success.

A selection breeding pattern for sexually dimorphic breast plumage color in Guangxi Yao chickens

The breast plumage color of Guangxi Yao chickens shows obvious sexual dimorphism, with roosters showing black and black with red, and hens displaying partridge and red. Black plumage in roosters is considered a sign of quality, necessitating the purification of plumage color. Here, we developed an effective method based on genetic variations within MC1R and plumage characteristics. We clarified the distribution of 5 single nucleotide polymorphisms (SNP) and 3 haplotypes (H1, H2, and H3) of MC1R gene, and revealed potential associations between haplotype H1 and black breast plumage in the F2 resource population derived from a backcross between Guangxi Yao and Yellow chickens. Subsequently, using H1/H1 diplotype roosters and hens to construct families (n = 1,244) notably increased the proportion of offspring with black plumage. Further analysis suggested that red plumage in hens may be the putative phenotype of black plumage in roosters, driven by haplotype H1 of the MC1R gene, as verified by genotype and phenotype analysis. As expected, we found that almost all male offspring of hens with red breast plumage showed black plumage. In short, we established a selection pattern based on the combination of black-plumage roosters and red-plumage hens can significantly purify the sexually dimorphic plumage color and improve the efficiency of breeding programs in Guangxi Yao chickens. Our findings provide a novel technical framework to accelerate the breeding process for plumage trait in poultry.

Sex difference in the association between creatinine-to-cystatin C ratio and metabolic syndrome among Chinese adults.

Metabolic syndrome (MetS), characterized by central obesity, insulin resistance, dyslipidemia, and hypertension, affects 20-25% of the global population. The creatinine-to-cystatin C ratio (CCR) is an indicator of skeletal muscle mass. While CCR may play a role in MetS development, sex differences in these associations are not fully understood. Therefore, this study aimed to investigate how CCR levels are associated with MetS in a Chinese adult population, focusing on possible sex disparities. We conducted a retrospective cross-sectional analysis of 9,376 adults from Xiamen Chang Gung Hospital between 2014 to 2016. We examined the relationship between CCR and MetS, adjusting for cardiometabolic risk factors. The prevalence of MetS was 24.7% in males and 18.0% in females. Interestingly, we observed significant sex differences in the association between CCR quartiles and MetS. Females in the lowest CCR quartile had a significantly higher risk of MetS (odds ratio=1.84). Receiver operating characteristic curve analysis revealed acceptable diagnostic power of CCR for MetS in females (area under the curve=0.65) but not in males. Our findings suggest that CCR is an independent risk factor for MetS in females, highlighting the importance of sex-specific assessments when evaluating MetS risk.

Spinal cord microglia drive sex differences in ethanol-mediated PGE2-induced allodynia

The mechanisms of how long-term alcohol use can lead to persistent pain pathology are unclear. Understanding how earlier events of short-term alcohol use can lower the threshold of non-painful stimuli, described as allodynia could prove prudent to understand important initiating mechanisms. Previously, we observed that short-term low-dose alcohol intake induced female-specific allodynia and increased microglial activation in the spinal cord dorsal horn. Other literature describes how chronic ethanol exposure activates Toll-like receptor 4 (TLR4) to initiate inflammatory responses. TLR4 is expressed on many cell types, and we aimed to investigate whether TLR4 on microglia is sufficient to potentiate allodynia during a short-term/low-dose alcohol paradigm. Our study used a novel genetic model where TLR4 expression is removed from the entire body by introducing a floxed transcriptional blocker (TLR4-null background (TLR4LoxTB)), then restricted to microglia by breeding TLR4LoxTB animals with Cx3CR1:CreERT2 animals. As previously reported, after 14 days of ethanol administration alone, we observed no increased pain behavior. However, we observed significant priming effects 3 hrs post intraplantar injection of a subthreshold dose of prostaglandin E2 (PGE2) in wild-type and microglia-TLR4 restricted female mice. We also observed a significant female-specific shift to pro-inflammatory phenotype and morphological changes in microglia of the lumbar dorsal horn. Investigations in pain priming-associated neuronal subtypes showed an increase of c-Fos and FosB activity in PKCγ interneurons in the dorsal horn of female mice directly corresponding to increased microglial activity. This study uncovers cell- and female-specific roles of TLR4 in sexual dimorphisms in pain induction among non-pathological drinkers.

Identification of regional and sex differences in asthma mortality trends in Spanish Autonomous Communities (1980–2022)

Objective Despite global declines in asthma mortality, regional variations and sex disparities persist. This study investigates asthma mortality trends in Spanish Autonomous Communities (ACs) from 1980 to 2022, analyzing data by sex. Methods Data on asthma deaths and population were obtained from the National Institute of Statistics for the study period. Age-standardized mortality rates (ASMRs) were calculated, and joinpoint regression models were applied to identify trends. Results Overall, 44,728 asthma deaths occurred, with a steeper decline observed in men (−3.5% per year) compared to women (−0.7% per year). The female-to-male mortality ratio climbed from 0.7 in 1980 to 5.4 in 2016. Both sexes exhibited a significant decrease in ASMRs, with a more substantial decline in males (−6.3%). While all ACs showed a significant decrease in male ASMRs, female trends varied, with significant decreases in 13 ACs and stable trends elsewhere. Joinpoint analysis revealed diverse regional patterns for both sexes, with some ACs experiencing steady declines and others exhibiting periods of slower decline or even stabilization. Conclusion This study identified concerning regional and sex disparities in Spanish ACs’ asthma mortality (1980–2022). While male rates declined significantly across all regions, female rates showed variation, with even increases in some ACs. Targeted interventions addressing these disparities and their underlying causes (healthcare access, management practices, etc.) are crucial.

Impact of sex on clinical and laboratory parameters in patients with heart failure: insights from the Colombian Heart Failure Registry (RECOLFACA)

Introduction Heart failure (HF) is one of the leading causes of morbidity and mortality worldwide. This study aimed to assess the impact of sex on sociodemographic, clinical, and laboratory parameters in patients with HF who were included in the Colombian Heart Failure Registry (RECOLFACA). Methods This was a cross-sectional analytical research. All 2528 patients included in RECOLFACA were analysed. The Mann–Whitney U test was used to compare median values as well as first and third quartiles (Q1–Q3). The age-related trend of NT-proBNP levels for both men and women groups was statistically evaluated. Results The study included 2528 patients with HF (1072 women and 1456 men). The echocardiographic evidence showed that men presented reduced left ventricular ejection fraction (LVEF) (79.63 vs. 69.75%, respectively; p < 0.001) more often than women, which had a significantly higher proportion of preserved LVEF (20.46 vs.11.24%, respectively; p < 0.001). Women displayed a higher value of systolic blood pressure (p < 0.001) and heart rate (p = 0.014) compared to men. Haemoglobin, creatinine, and sodium levels were significantly higher in men. Men had a considerably lower glomerular filtration rate value, with the median reaching a G3a value for chronic renal failure. According to age, the levels of NT-proBNP in each sex increased equivalently with age. Conclusion Sex differences presented in this study are comparable to those discovered in other nations. However, certain variations show that these sex differences may differ by geographical area, which should encourage further investigations to describe them.

The Activity Patterns and Grouping Characteristics of the Remaining Goitered Gazelle (Gazella subgutturosa) in an Isolated Habitat of Western China.

Wildlife activity patterns, which reveal the daily allocation of time and energy, are crucial for understanding survival pressures, adaptive strategies, and behavioral characteristics in different environments. Among ungulates, grouping behavior is a prevalent adaptive trait that reflects the population structure, mating systems, and life history strategies formed over long-term evolutionary processes. This study aimed to elucidate the daily activity patterns and grouping characteristics of the rare goitered gazelle (Gazella subgutturosa) in the Helan Mountains of western China from 2022 to 2023 using camera trap monitoring. With a total of 3869 camera days of effective trapping, we recorded 442 independent detections of goitered gazelles. The results revealed the following: (1) Goitered gazelle is primarily active during the day, showing an activity pattern similar to crepuscular animals, with two activity peaks occurring after dawn and before dusk. (2) Daily activity patterns showed both seasonal and sex differences. In the warm season, morning activity peaks occurred earlier, and afternoon peaks occurred later compared to the cold season. The overlap in daily activity patterns between females and males in the warm season was lower than that in the cold season, and this trend persisted throughout the year. (3) The number of times different types of groups were observed varied significantly, with single males and single females accounting for a larger proportion of all observed groups. There was no significant difference in group size across seasons, with groups typically consisting of 1-2 individuals. Our study provides detailed insights into the temporal ecology and population structure of goitered gazelles in arid and semi-arid ecosystems. This information will guide the identification of future conservation priorities and the development of management plans for the reserve.

MiR-34 negatively regulates the expression of Dmrt and related genes in the testis of mud crab Scylla paramamosain

The mud crab (Scylla paramamosain) is a commercially significant marine decapod crustacean. Due to its obvious sexual dimorphism, the mechanism of sex differentiation and gonadal development has attracted significant research interest. The Dmrt (double-sex and mab-3 related transcription factor) genes are vital in animal gonadal development and sex differentiation. In the present study, miR-34 was predicted to target the 3′ end of Dmrt-1, idmrt-2, Dmrt-3, Dsx and Dmrt-like genes by prediction software, and the interactions between miR-34 and these Dmrt genes were validated by in vivo and in vitro experiments. Dual luciferase assay results indicated that miR-34 mimics/inhibitors co-transfected with plasmid vectors with 3′ end of Dmrt-1, idmrt-2, Dmrt-3, Dsx and Dmrt-like, respectively, led to a significant decrease/increase of fluorescence activity in HEK293T cells. In vivo experiments showed that injection of agomir-34 significantly inhibited Dmrt-1, idmrt-2, Dsx and Dmrt-like expression, while injection of antagomir-34 caused the opposite result. However, Dmrt-3 expression was not affected by injection of miR-34 reagents. Meanwhile, the expression of spermatogenesis and testicular development-related molecular marker genes (IAG, foxl2 and vasa) in mud crabs was significantly changed after injecting the miR-34 reagent in vivo. Furthermore, the result of immunoblotting proved that the expression level of Dmrt-like protein can be regulated by miR-34. These results imply that miR-34 is indirectly involved in sex differentiation and testicular development of S. paramamosain by regulating Dmrt-1, idmrt-2, Dsx and Dmrt-like genes.

A retrospective study of tracheal collapse in small-breed dogs: 110 cases (2022-2024).

The grade of tracheal collapse (TC) is assessed by the diameter of the narrowed lumen. However, studies on the relationship between TC grade and clinical symptom severity are lacking. To investigate the clinical characteristics of small-breed dogs diagnosed with TC and determine if fluoroscopic grading correlates with cough severity. We retrospectively reviewed medical records from 2022 to 2024. TC diagnosis was confirmed using fluoroscopic examination. Multiple linear regression was employed to investigate factors influencing cough severity, with a significance level set at p < 0.05. A total of 132 dogs with TC were identified, of which 22 were excluded. The final cohort consisted of 110 dogs, aged between 2-19 years, with no significant sex differences. The majority (97.2%) of dogs had a BCS of ≥4. Among the top four breeds (Maltese, Pomeranian, Poodle, and Chihuahua), the most severe collapse was observed in the carinal region. The grade of collapse on fluoroscopy was mostly related to high BCS (p < 0.007) and low body weight (p < 0.001). However, interestingly, fluoroscopic findings of collapse location and grade did not correlate with cough severity (p = 0.350). Notably, clinical symptoms improved in 86.6% of cases following interventions such as weight reduction, environmental changes, and pharmacotherapy. In small-breed dogs, the severity of cough was not associated with the region or grade of TC diagnosed by fluoroscopy.

Birth outcomes and survival by sex among newborns and children under 2 in the Birhan Cohort: a prospective cohort study in the Amhara Region of Ethiopia

IntroductionDespite the progress in reducing child mortality, the rate remains high, particularly in sub-Saharan African countries. Limited data exist on child survival and other birth outcomes by sex. This study...

The Link Between Temporomandibular Disorders and Jaw Functional Limitations Among Chinese Adolescents

BackgroundCurrently, there is still controversy surrounding the relationship between temporomandibular disorders (TMDs) symptoms and jaw functional limitations. We investigated the distribution of TMDs in senior high school students, including both the number and types of symptoms, and assessed their association with jaw functional limitations. Furthermore, we explored sex differences in these associations. MethodsThis study was conducted at a public high school in Hefei, Anhui Province, China, with data collected from September to October 2022. All subjects completed questionnaires assessing the anamnestic symptoms of TMDs and the Jaw Functional Limitation Scale (JFLS), and examinations were performed by trained dentists according to the Diagnostic Criteria for TMD. Data were analysed using the Kruskal–Wallis, Mann–Whitney U, and Chi-square tests. ResultsThe mean age of the participants (N = 2890) was 17.2 ± 0.14 years and 38.9% were females (61.1% were males). Limitations in self-assessed jaw function were associated with the presence of TMDs (P < .05). Participants with more symptoms reported significantly high levels of functional limitations (P < .05). Compared to male adolescents, female adolescents more commonly experienced TMDs pain and tended to have more symptoms (P < .05). However, no sex differences were observed in most associations between TMDs and jaw functional limitations. ConclusionTMDs-positive symptoms are common in adolescents. Female adolescents were more affected by TMDs symptoms than male adolescents. Individuals with more TMDs symptoms have greater jaw functional limitations.

Tracking the Prevalence of Obesity in Portuguese School-Aged Children: What Future to Expect?

Childhood obesity presents a significant public health concern globally, with implications for cardiovascular health and metabolic syndrome. In Portugal, approximately 31.6% of children are affected, highlighting the urgency for intervention strategies. This study aimed to assess the prevalence of overweight and obesity in Portuguese school-aged children, with a focus on sex and age differences. Anthropometric measurements were conducted on 1564 children aged 6-10 years, including weight, height, and skinfold thickness. Body Mass Index (BMI) and the percentage of body fat were calculated using established methods. The results revealed significant differences in BMI (≤0.001) and body fat percentage (≤0.001) among different BMI categories, with a notable prevalence of overweight and obesity, particularly among boys. A total of 37% of the studied population is overweight or obese, among which 40.1% and 33.9% are boys and girls, respectively. This study highlights statistically significant differences in BMI and body fat percentage for both sexes in different BMI categories. A large proportion of the population is overweight or obese, with a greater prevalence in boys. In short, childhood obesity has a negative impact on body composition and is associated with significant differences in anthropometric parameters, emphasizing the importance of preventative and intervention strategies to address this health problem.

Neurocognitive Latent Factors Associate With Early Tobacco and Alcohol Use Among Adolescent Brain Cognitive Development Study Youth

PurposeProspective associations between preadolescent neurocognitive structure and onset of substance use in adolescence have not been examined. This study investigated associations between cognitive structure among youth aged 9 – 10 years and the likelihood of experimentation with tobacco and alcohol by ages 13–14 years. MethodsA principal component (PC) analysis of nine neurocognitive assessments was used to identify the cognitive structure of unrelated adolescent brain cognitive development study participants (n = 9,655). We modeled associations between neurocognitive PCs and odds of tobacco or alcohol use by ages 13–14 years using generalized linear mixed models with a logit link and random intercept for recruitment sites. Demographics, family conflict, neighborhood safety, and externalizing and internalizing behavior were considered covariates. ResultsFour neurocognitive PCs were identified and labeled general ability, executive function, learning and memory, and mental rotation. Mental rotation [odds ratio [OR] = 0.88, p-value = .013] was associated with lower odds of youth tobacco use; the association was stronger among female youth. General ability [OR = 1.20, p-value < .0001] among both males and females, and learning and memory [OR = 1.11, p-value = .024] among females, were associated with increased odds of youth alcohol use. DiscussionAmong youth, higher neurocognitive performance was protective for tobacco use but increased the likelihood of alcohol use. Potential sex differences were identified. The role of cognition in processing the social contexts surrounding tobacco and alcohol use in the United States may contribute to the formation of disparate youth expectancies for tobacco and alcohol use.

FGF21 mediating the Sex-dependent Response to Dietary Macronutrients.

Sex is key variable influencing body composition and substrate utilization. At rest, females maintain greater adiposity than males and resist the mobilization of fat. Males maintain greater lean muscle mass and mobilize fat readily. Determining the mechanisms that direct these sex-dependent effects is important for both reproductive and metabolic health. Here, we highlight the fundamental importance of sex in shaping metabolic physiology and assess growing evidence that the hepatokine fibroblast growth factor-21 (FGF21) plays a mechanistic role to facilitate sex-dependent responses to a changing nutritional environment. First, we examine the importance of sex in modulating body composition and substrate utilization. We summarize new data that point toward sex-biased effects of pharmacologic FGF21 administration on these endpoints. When energy is not limited, metabolic responses to FGF21 mirror broader sex differences; FGF21-treated males conserve lean mass at the expense of increased lipid catabolism, whereas FGF21-treated females conserve fat mass at the expense of reduced lean mass. Next, we examine the importance of sex in modulating the endogenous secretion of FGF21 in response to changing macronutrient and energy availability. During the resting state when energy is not limited, macronutrient imbalance increases the secretion of FGF21 more so in males than females. When energy is limited, the effect of sex on both the secretion of FGF21 and its metabolic actions may be reversed. Altogether, we argue that a growing literature supports FGF21 as a plausible mechanism contributing to the sex-dependent mobilization vs preservation of lipid storage and highlight the need for further research.

The influence of the interventionalist's sex on the outcome and complications of transbronchial lung cryobiopsy

BackgroundTo date there are no data on sex aspects evaluating outcomes of interventional pneumology (IP). Our aim was to investigate sex differences in transbronchial lung cryobiopsy (TBLC) outcomes in the diagnosis of interstitial lung disease (ILD). MethodsAll consecutive (TBLC)s performed for ILD evaluation between Nov 17 and Dec 21 at a tertiary referral center for ILDs and IP were analyzed. The indication for the procedure was determined by a multidisciplinary discussion (MDD). Final results including bronchoalveolar lavage (BAL) and histology were discussed in a 2nd MDD and outcomes and procedure related complications were assessed. ResultsTBLC was performed in 406 patients (38.4 % female/67.8 years/FVC 76.8 %). Among 32 interventionalists, 16 females performed 53 % of interventions. Females had longer procedure times (29.9 vs. 26.6 min, p = 0.046), used fluoroscopy more often (76.7 vs. 50.3 %, p < 0.001) and obtained more samples (3.6 vs. 3.2, p = 0.021) than their male counterparts. No difference was found for major bleeding or pneumothorax. MDD was able to conclude on a diagnosis in 88.4 % of interventions performed by women and in 78.5 % performed by men (p = 0.010). In a multivariate analysis, female gender (OR 1.93) and lower FVC% values (OR 0.98) were significantly associated with diagnostic yield, whereas the number of biopsies, professional experience, use of fluoroscopy or antiplatelet drugs were not relevant. ConclusionThe results of this study strengthen the role of women in endoscopy and may help to motivate women to pursue a career in IP.

Differential brainstem connectivity according to sex and menopausal status in healthy men and women.

Brainstem nuclei play a critical role in both ascending monoaminergic modulation of cortical function and arousal, and in descending bulbospinal pain modulation. Even though sex-related differences in the function of both systems have been reported in animal models, a complete understanding of sex differences, as well as menopausal effects, in brainstem connectivity in humans is lacking. This study evaluated resting-state connectivity of the dorsal raphe nucleus (DRN), right and left locus coeruleus complex (LCC), and periaqueductal gray (PAG) according to sex and menopausal status in healthy individuals. In addition, relationships between systemic estrogen levels and brainstem-network connectivity were examined in a subset of participants. Resting-state fMRI was performed in 50 healthy men (age, 31.2 ± 8.0 years), 53 healthy premenopausal women (age, 24.7 ± 7.3 years; 22 in the follicular phase, 31 in the luteal phase), and 20 postmenopausal women (age, 54.6 ± 7.2 years). Permutation Analysis of Linear Models (5000 permutations) was used to evaluate differences in brainstem-network connectivity according to sex and menopausal status, controlling for age. In 10 men and 17 women (9 premenopausal; 8 postmenopausal), estrogen and estrogen metabolite levels in plasma and stool were determined by liquid chromatography-mass spectrometry/mass spectrometry. Relationships between estrogen levels and brainstem-network connectivity were evaluated by partial least squares analysis. Left LCC-executive control network (ECN) connectivity showed an overall sex difference (p = 0.02), with higher connectivity in women than in men; however, this was mainly due to differences between men and pre-menopausal women (p = 0.008). Additional sex differences were dependent on menopausal status: PAG-default mode network (DMN) connectivity was higher in postmenopausal women than in men (p = 0.04), and PAG-sensorimotor network (SMN) connectivity was higher in premenopausal women than in men (p = 0.03) and postmenopausal women (p = 0.007). Notably, higher free 2-hydroxyestrone levels in stool were associated with higher PAG-SMN and PAG-DMN connectivity in premenopausal women (p < 0.01). Healthy women show higher brainstem-network connectivity involved in cognitive control, sensorimotor function, and self-relevant processes than men, dependent on their menopausal status. Further, 2-hydroxyestrone, implicated in pain, may modulate PAG connectivity in premenopausal women. These findings may relate to differential vulnerabilities to chronic stress-sensitive disorders at different life stages.

Fistulizing Perianal Disease as a First Manifestation of Crohn's Disease: A Systematic Review and Meta-Analysis.

Background: Incidences of perianal fistulas (PAFs) as a first manifestation of Crohn's disease (CD) vary widely in the literature. Aim: To analyse the percentage of patients with a PAF preceding CD diagnosis and assess the time to diagnosis. Methods: A systematic literature search was conducted. Studies reporting on patients with a PAF preceding CD diagnosis were identified. Primary outcomes were the (weighted) percentage of patients with CD with a PAF preceding CD and their time to CD diagnosis. Secondary outcomes were the (weighted) percentage of patients with CD with a PAF preceding CD diagnosis in predefined patient subgroups, including (1) sex (men vs. women), (2) ethnicity (Asian vs. non-Asian), and (3) age (paediatric (0-18 y) and patients with elderly onset CD (>60 y) vs. adult patients (18-60 y)). Results: Seventeen studies were included (34,030 patients with CD). In the overall CD population, a PAF preceded CD in 8.6% [95%CI; 5.72; 12.71] with a weighted mean time to CD diagnosis of 45.9 (31.3) months. No studies reported details on sex differences in patients with a PAF as a manifesting sign of CD. In Asian populations, a PAF preceded CD in 17.66% [95%CI; 11.45; 26.25], which was significantly higher when compared with non-Asians (4.99% [95%CI; 3.75; 6.60], OR:3.99, p < 0.0001). In adolescents, an incidence of 9.17% [95%CI; 5.92; 13.93] was found with significantly lower incidences in paediatric patients (6.38% [95%CI; 1.84; 19.85], OR:0.53, p < 0.0001), and elderly-onset patients (3.77% [95%CI; 1.68; 8.25], OR:0.44, p = 0.0035). Conclusions: This systematic review shows that in the literature, almost 10% of patients present with a PAF as a first manifestation of CD, with a mean time to diagnosis of almost four years. These results emphasise that increased clinical awareness is needed.

Sex difference alters the behavioral and cognitive performance in a rat model of schizophrenia induced by sub-chronic ketamine

Schizophrenia is a complex neuropsychiatric disorder with positive, negative, and cognitive symptoms. In rats, sub-chronic administration of ketamine is used for the induction of schizophrenia model. Increased locomotor activity is one of the most important features of psychotic-like symptoms in rodents. On the other hand, risperidone is a potent antipsychotic medication that is approved for the treatment of schizophrenia and bipolar disorder. In the present research, we aimed to investigate the effect of sub-chronic treatment of ketamine on cognitive and behavioral functions, and brain-derived neurotrophic factor (BDNF) expression level in the prefrontal cortex. Also, we assessed the efficacy of risperidone on cognitive and behavioral impairments induced by ketamine. Possible sex differences were also measured. Ketamine was intraperitoneally injected at the dose of 30 mg/kg for five consecutive days. Risperidone was also intraperitoneally injected at the dose of 2 mg/kg. Novel object recognition memory, pain threshold, locomotor activity, rearing behavior, and BDNF level were evaluated. The results showed that ketamine injection for five consecutive days impaired the acquisition of long-term recognition memory and decreased BDNF level in the prefrontal cortex in both sexes. Also, it decreased pain threshold in females, increased rearing behavior in males, and induced hyperlocomotion with greater effect in females. On the other hand, risperidone restored or attenuated the effect of ketamine on all the behavioral effects and BDNF level. In conclusion, we suggested that there were sex differences in the effects of ketamine on pain perception, locomotion, and rearing behavior in a rat model of schizophrenia.

Association of Anxiety/Depressive Symptoms with Psychotic-like Experiences: The Moderation Effect of Sex and Resilience.

Psychotic-like experiences (PLEs) are a part of the continuum of psychosis and are common in the general population. While most of these experiences are transient, they are strongly correlated with an increased risk of various adverse psychological outcomes. Anxiety and depressive symptoms also occur frequently in the adolescent population. Much research has previously demonstrated a correlation between these two symptoms and PLEs. However, few investigations have examined what influences this association, and sex and resilience may be important moderators. This study selected a sample of first-year students from a university in Shanghai. A total of 2970 adolescents completed questionnaires measuring sociodemographic characteristics, anxiety/depressive symptoms by SCL-90, resilience by CD-RISC, and self-reported PLEs by PQ-16. The findings indicated that PLEs were prevalent in the sample, with at least one PQ-16 item present in 42.5% of individuals. Anxiety/depressive symptoms were significantly associated with PLEs, and there was a sex difference in this association (p < 0.001). What is more, this relationship was stronger in males than in females. Additionally, we found a significant interaction (p < 0.001) between resilience and anxiety/depressive symptoms when looking at the correlates of PLEs. Those with stronger resilience showed a considerably weaker connection between PLEs and symptoms of anxiety and depression. These findings can potentially inform the development of targeted new clinical interventions.