Significant Sexual Dimorphism Research Articles

Assessment of Vidian canal morphology in axial section and its associated structures using cone beam computed tomography: A descriptive study

The Vidian Nerve (VN), a branch of the trigeminal nerve, passes by the Vidian Canal (VC), located at the base of the skull. The VC branches into the greater petrosal nerve and the VN in the pterygopalatine fossa, where the greater petrosal nerve carries parasympathetic fibers to the lacrimal glands and nasal mucosa, and the VN carries sensory fibers from the nasopharynx, nasal cavity, and palate. In this study, 60 subjects of both sexes who underwent cone beam computed tomography (CBCT) were selected by a convenient sampling technique. The data were subjected to statistical analysis following the examination of the various parameters in the axial sections. Among the various morphological characteristics appraised in the axial section, there was no significant sexual dimorphism, except for the angle between the VC and the medial wall of the maxillary sinus, which shows statistical significance. The present study aims to investigate morphometric analysis and its associated structures, offering insightful information about the complex structure of the Vidian canal (VC), which provides adequate knowledge for surgeons to plan with more caution complex skull base procedures, and eventually to lower the therapeutical risks associated with it.

Sex Estimation Using Heel-Ball Index: A Metric-Based Comparative Study on Foot and Footprint Dimensions.

Background: Sexual dimorphism plays a vital role in individual identification, and body dimensions can contribute to establishing a biological profile for identification purposes. Aims and Objectives: To determine the reliability of the Heel-Ball Index (HBI) in estimating sex from foot dimensions and footprint dimensions and also to investigate the potential of dimensions and indices, using a standardized value, in estimating sex, from foot dimensions and footprint dimensions. Materials and Methods: In this study, a group of 112 young Indian adults aged 18 to 22, consisting of 56 males and 56 females, was examined. The foot breadth at ball (BBAL) and foot breadth at heel (BHEL) of both feet were measured using sliding digital calipers from foot and footprint dimensions. Results: Significant sexual dimorphism was observed in BBAL, BHEL, and HBI (HBI = BHEL/BBAL × 100) measurements in both feet of both sexes. Conclusion: HBI yielded better accuracy for foot dimensions than footprint dimensions. It was also found that utilizing absolute foot dimensions (BBAL and BHEL) yielded more accurate results in estimating sex compared to the HBI, which is calculated as a ratio of absolute measurements.

Sex estimation from patellar measurements in a contemporary Italian population: a machine learning approach.

Biological sex estimation in forensic anthropology is a crucial topic, and the patella has shown promise in this regard due to its sexual dimorphism. This study uses 12 machine learning models for sex estimation based on three patellar measurements (maximum height, breadth, and thickness). Data was collected from 180 skeletons of a contemporary Italian population (83 males and 97 females) as well as from an independent sample of 21 forensic cases (13 males and 8 females). Statistical analyses indicated that each of the variables exhibited significant sexual dimorphism. To predict biological sex, the classifiers were built using 70% of a reference sample, then tested on the remaining 30% of the original sample and then tested again on the independent sample. The different classifiers generated accuracies varied between 0.85 and 0.91 on the reference sample and between 0.71 and 0.95 for the validation sample. SVM classifier stood out with the highest accuracy and seemed the best model for our study.This study contributes to the growing application of machine learning in forensic anthropology by being the first to apply such techniques to patellar measurements in an Italian population. It aims to enhance the accuracy and efficiency of biological sex estimation from the patella, building on promising results observed with other skeletal elements.

Morphometric analysis of the hard palate in sex estimation among koreans using three-dimensional computed tomography

Accurate sex estimation is crucial for comprehensive analysis of the biological profiles of unidentified human skeletal remains. However, there is a notable lack of research specifically addressing the morphometrics of the hard palate. Therefore, this study aimed to derive discriminant equations using the hard palate and assess their applicability for sexing partial skeletal remains in a contemporary Korean population. Statistical analyses were performed for 24 measurements derived from three-dimensional models of the hard palate, generated using computed tomography scans of 301 individuals (156 males, 145 females). Descriptive statistics revealed significant sexual dimorphism in the mean comparison of hard palate sizes between Korean males and females, with males exhibiting larger palates across all measurements (p < 0.05). Discriminant function score equations were generated to aid in sex determination. Univariate analysis yielded an accuracy range of 57.8–75.1%, whereas the stepwise method achieved an accuracy of 80.7% with five selected variables: IF-PNS, GFL-GFR, IF-GFR, Pr-EcL, and Pr-EnR. The results of this metric analysis demonstrate the usefulness of the hard palate for sex estimation in the contemporary Korean population. These findings have potential implications for forensic investigations, archeological studies, and population-specific anatomical research.

Sex determination and odontometric dimensions - A study of a North Indian population.

Sex determination is an indispensable parameter in identifying unknown deceased individuals. It can narrow down the chances of possible matches by 50%, providing a crucial lead in personal identification. In cases of commingled, decomposed, fragmented, charred and unidentifiable corpses, the importance of dental morphometrics cannot be overlooked due to the resistance of teeth to post-mortem degradation. Addressing this quality of teeth, a descriptive cross-sectional study was conducted in a North Indian population to evaluate sexual variations in dental dimensions and to identify the most sexually dimorphic dental dimension. The study included 207 participants (114 females and 93 males) in the age group of 21 to 45 years. Dental casts were prepared after obtaining informed consent from the participants and ethical clearance from the institute's ethical committee. Six odontometric dimensions, namely incisor-incisor distance, inter canine distance, combined width of central incisors, inter-premolar distance, inter-molar distance, and dental arch height of each participant were recorded on the dental casts using standard procedures. Analysis of the data elucidated the existence of statistically significant sexual dimorphism in the dental dimensions of the participants. The results of the discriminant function analysis show a sex determination accuracy of 68.1%, with a cross-validation accuracy of 65.2%. The study found the incisor-incisor distance to be the most sexually dimorphic trait, making it the best predictor of sex in the present population. The results of the present study may be helpful in sex determination and personal identification from dental remains in medico-legal and disaster victim identification cases.

Biometric analysis of the cranial features of common voles

Although cranial bones reliably identify the features of mammals, these traits can be affected by sex, population size and seasonality. This paper biometrically analyses the cranial features of the common vole. The research sample consisted of adult (n = 134), subadult (n = 57), of western Slovakia. Overall, software based on the highlighted marks measured 29 cranial features. Significant sexual dimorphism was observed for three features in adult individuals (width of the maxillary tooth row – right side “WMTRR”, maximum height of the mandibula excluding coronoid process “AMdm” and coronoid height of the mandibula “AMd”) and four features in subadults (length of the tooth row in the maxilla “LOSD”, “WMTRR”, length of the molar “LoM” and alveolar length of the lower molars “ALLM”). Results showed a significant positive relationship between body weight and cranial size in 18 of the 29 features. They also suggested a weak but significant positive effect of common vole abundance on cranium size (Chitty effect) likewise in 6 of the 29 features. In several cases, this effect affects, in addition to the abundance, the onset of sexual maturity of individuals.

The Ultramorphology and Sexual Dimorphism of Antennae and Sensilla in the Pale Grass Blue, Pseudozizeeria maha (Lepidoptera: Lycaenidae).

The pale grass blue, Pseudozizeeria maha, is a small lycaenid butterfly widely distributed across Asia. Due to its exclusively diurnal lifestyle and conspicuous sexual dimorphism in wing coloration, vision has traditionally been regarded as the primary sensory system driving various behaviors. However, non-visual sensory systems related to sex-specific behavioral responses, such as antennae, have received far less attention. This study investigated the morphological characteristics and sensilla types of the antennae in adult P. maha using scanning electron microscopy, with a focus on potential sexual dimorphism. The antennae of adult P. maha are clavate, with no significant sexual differences in overall morphology. Six types of antennal sensilla were identified: Böhm bristles, sensilla squamiformia, sensilla trichodea, sensilla chaetica, sensilla basiconica, and sensilla coeloconica, with no sexual dimorphism observed in their morphological types or dimensions. Remarkably, the sensilla coeloconica exhibit significant sexual dimorphism, with a more prominent presence in females. This finding suggests that female P. maha may rely more on olfactory cues for some sex-specific behaviors, such as oviposition site selection.

Impact of Sex on the Therapeutic Efficacy of Rosiglitazone in Modulating White Adipose Tissue Function and Insulin Sensitivity.

Obesity and type 2 diabetes mellitus are global public health issues. Although males show higher obesity and insulin resistance prevalence, current treatments often neglect sex-specific differences. White adipose tissue (WAT) is crucial in preventing lipotoxicity and inflammation and has become a key therapeutic target. Rosiglitazone (RSG), a potent PPARγ agonist, promotes healthy WAT growth and mitochondrial function through MitoNEET modulation. Recent RSG-based strategies specifically target white adipocytes, avoiding side effects. Our aim was to investigate whether sex-specific differences in the insulin-sensitizing effects of RSG exist on WAT during obesity and inflammation. We used Wistar rats of both sexes fed a high-fat diet (HFD, 22.5% fat content) for 16 weeks. Two weeks before sacrifice, a group of HFD-fed rats received RSG treatment (4 mg/kg of body weight per day) within the diet. HFD male rats showed greater insulin resistance, inflammation, mitochondrial dysfunction, and dyslipidemia than females. RSG had more pronounced effects in males, significantly improving insulin sensitivity, fat storage, mitochondrial function, and lipid handling in WAT while reducing ectopic fat deposition and enhancing adiponectin signaling in the liver. Our study suggests a significant sexual dimorphism in the anti-diabetic effects of RSG on WAT, correlating with the severity of metabolic dysfunction.

Assessment of age-dependent sexual dimorphism in paediatric vertebral size and density using a statistical shape and statistical appearance modelling approach

This work focuses on the growth patterns of the human fourth lumbar vertebra (L4) in a paediatric population, with specific attention to sexual dimorphism. The study aims to understand morphological and density changes in the vertebrae through age-dependent statistical shape and statistical appearance models, which can describe full three-dimensional anatomy. Results show that the main growth patterns are associated with isotropic volumetric vertebral growth, a decrease in the relative size of the vertebral foramen, and an increase in the length of the transverse processes. Moreover, significant sexual dimorphism was demonstrated during puberty. We observe significant age and sex interaction in the anterior vertebral body height (P = 0.005), where females exhibited an earlier increase in rates of vertebral height evolution. Moreover, we also observe an increase in cross-sectional area (CSA) with age (P = 0.020), where the CSA is smaller in females than in males (significant sex effect P = 0.042). Finally, although no significant increase in trabecular bone density with age is observed (P = 0.363), a trend in the statistical appearance model suggests an increase in density with age.

Histological observations and transcriptome analyses reveal the dynamic changes in the gonads of the blotched snakehead (Channa maculata) during sex differentiation and gametogenesis

BackgroundBlotched snakehead (Channa maculata) displays significant sexual dimorphism, with males exhibiting faster growth rates and larger body sizes compared to females. The cultivation of the all-male population of snakeheads holds substantial economic and ecological value. Nonetheless, the intricate processes governing the development of bipotential gonads into either testis or ovary in C. maculata remain inadequately elucidated. Therefore, it is necessary to determine the critical time window of sex differentiation in C. maculata, providing a theoretical basis for sex control in production practices.MethodsThe body length and weight of male and female C. maculata were measured at different developmental stages to reveal when sexual dimorphism in growth initially appears. Histological observations and spatiotemporal comparative transcriptome analyses were performed on ovaries and testes across various developmental stages to determine the crucial time windows for sex differentiation in each sex and the sex-related genes. Additionally, qPCR and MG2C were utilized to validate and locate sex-related genes, and levels of E2 and T were quantified to understand sex steroid synthesis.ResultsSexual dimorphism in growth became evident starting from 90 dpf. Histological observations revealed that morphological sex differentiation in females and males occurred between 20 and 25 dpf or earlier and 30–35 dpf or earlier, respectively, corresponding to the appearance of the ovarian cavity or efferent duct anlage. Transcriptome analyses revealed divergent gene expression patterns in testes and ovaries after 30 dpf. The periods of 40–60 dpf and 60–90 dpf marked the initiation of molecular sex differentiation in females and males, respectively. Male-biased genes (Sox11a, Dmrt1, Amh, Amhr2, Gsdf, Ar, Cyp17a2) likely play crucial roles in male sex differentiation and spermatogenesis, while female-biased genes (Foxl2, Cyp19a1a, Bmp15, Figla, Er) could be pivotal in ovarian differentiation and development. Numerous biological pathways linked to sex differentiation and gametogenesis were also identified. Additionally, E2 and T exhibited sexual dimorphism during sex differentiation and gonadal development. Based on these results, it is hypothesized that in C. maculata, the potential male sex differentiation pathway, Sox11a–Dmrt1–Sox9b, activates downstream sex-related genes (Amh, Amhr2, Gsdf, Ar, Cyp17a2) for testicular development, while the antagonistic pathway, Foxl2/Cyp19a1a, activates downstream sex-related genes (Bmp15, Figla, Er) for ovarian development.ConclusionsThis study provides a comprehensive overview of gonadal dynamic changes during sex differentiation and gametogenesis in C. maculata, establishing a scientific foundation for sex control in this species.

The easternmost occurrence of the Late Miocene schizotheriine chalicothere Ancylotherium pentelicum at the classical locality of Maragheh (Iran)

The renowned Late Miocene locality of Maragheh (northwest Iran) has yielded ample material of chalicotheres, most of which has never been described in detail. The present study concerns the taxonomic evaluation of this material and its attribution to the large schizotheriine Ancylotherium pentelicum. This allows a detailed comparison to schizotheriine material from other localities, and based on this, we provide an overview of the diagnostic features of Ancylotherium that separate it from all other chalicotheres. This improves our understanding of the type species A. pentelicum. Additionally, we discuss the palaeobiogeography of the species, which is best known from the Balkan Peninsula. Maragheh marks the easternmost occurrence of A. pentelicum, but its presence has even been suggested in Africa. Lastly, we discuss the existence of sexual size dimorphism in the species, based on the herein described material along with previously described specimens of A. pentelicum from other fossil sites, such as the famous Late Miocene localities Pikermi and Samos (Greece). Specifically, it is shown that many postcranial elements exhibit great size variability that is most probably associated with significant sexual dimorphism.

Association between maxillary incisor width and craniofacial measurements: A cone beam computed tomography study

Accurate prediction of maxillary central incisor width (CIW) is essential in prosthodontics for selecting appropriately sized denture teeth. While traditional methods exist, the digital era may offer more reliable techniques for anterior tooth selection. The purpose of this study was to investigate the correlation between CIW and craniofacial measurements derived from cone beam computed tomography (CBCT) scans to identify predictors for CIW and examine possible sexual dimorphism. A retrospective analysis was conducted on 80 three-dimensional skull models (40 men, 40 women; age range: 20 to 48 years) generated from segmented CBCT scans. Measurements included CIW, interpterygoid hamulus distance, bi-orbital width, interorbital distance, and piriform aperture width. Statistical analyses comprised independent t tests, bivariate correlations, and multiple linear regression (α=.05). Significant sexual dimorphism was observed in CIW, interpterygoid hamulus distance, and bi-orbital width (P<.05). CIW positively correlated with bi-orbital width (r=.75, P<.001) and piriform aperture width (r=.49, P<.001). Multiple regression analysis revealed bi-orbital width, and interorbital distance, along with sex, as significant predictors of CIW (R²=.59, P<.001). Bony bi-orbital width, interorbital distance, and sex can be used to estimate the maxillary CIW.

Exploitation and Application of a New Genetic Sex Marker Based on Intron Insertion Variation of erc2 Gene in Oplegnathus punctatus.

Spotted knifejaw (Oplegnathus punctatus), one of the most valuable mariculture species, grows with significant sexual dimorphism, with males growing significantly faster than females. O. punctatus not only has excellent growth characteristics and high food value, but also shows high economic value in aquaculture, which has become a hotspot in the field of aquaculture. The current insufficiency of sex marker identification in O. punctatus restricts the process of its unisexual breeding. Rapid identification of sex will help to study the mechanisms of sex determination and accelerate the development of sex-controlled breeding. With the completion of the sequencing of the male and female genomes of O. punctatus, the efficient and precise development of genetic sex markers has been made possible. In this study, we used genome-wide information combined with molecular biology techniques from marker sequences to further establish a rapid method for DNA insertion variant detection in the intron of O. punctatus erc2 gene, which can be used to rapidly, accurately, and efficiently identify whether DNA insertion occurs in the intron of O. punctatus erc2 gene to be detected, and to identify the sex of O. punctatus to be detected. It could also be distinguished by agarose gel electrophoresis, which would shorten the time for accurate identification and improves the detection efficiency. Homozygous comparison of male and female individuals showed that the length of the DNA fragment of the erc2 gene was 239bp on chromosome X1 and 1173bp on chromosome Y. It can therefore be inferred that a 934bp insertion fragment exists on the Y chromosome. The PCR amplification results showed that two DNA fragments of 1173bp and 239bp could be amplified in male O. punctatus, and the 1173bp fragment was a marker fragment specific to the variant intron erc2 gene, while only a single DNA fragment of 239bp was amplified in female O. punctatus. It has important significance and application value in the study of neurotransmitter transmission and environmental adaptability of female and male fish based on erc2 gene, as well as the identification of male and female sex, the preparation of high male fry, and family breeding.

Cephalometric Analysis of Maxillary Sinus for Gender Determination Using Lateral Cephalogram: A Novel Retrospective Study in the North Indian Population.

Underlying disorders of the maxillary sinus (MS), including a history of sinus surgeries, chronic sinusitis, or congenital anomalies can potentially impact sinus function and structure, necessitating careful evaluation and management. Moreover, intact sinuses are crucial in gender determination in forensic anthropology. The present study was undertaken to check the accuracy and reliability of MS in gender determination using morphometric parameters. This retrospective study was carried out on 74 lateral cephalograms (37 males and 37 females) aged between 18 to 50 years from the North Indian population. The MS area was measured using a NewTom CBCT machine (NewTom,Imola, Italy) with slicer software. The anatomical landmarks for the sinus were identified, and the area was calculated in square millimeters (mm2). In terms of surface area, females had a mean of 13,210.40 mm2 with a standard error of 713.46. Males, however, exhibited a higher mean surface area of 18,713.82 mm2, but with a significantly larger standard error of 3,371.70. The difference in MS area between males and females was statistically significant (p<0.01). In the receiver operating characteristic (ROC) curve, the area under the curve (AUC) was 0.77, suggesting good discriminative ability. The MS area on lateral cephalograms shows significant sexual dimorphism. Overall, the findings suggest that the MS surface area can be a useful anatomical feature for distinguishing between male and female North Indian subjects, given the statistically significant difference and the good discriminative performance indicated by the ROC curve analysis.

Characteristics of the Vasa Gene in Silurus asotus and Its Expression Response to Letrozole Treatment.

The identification and expression of germ cells are important for studying sex-related mechanisms in fish. The vasa gene, encoding an ATP-dependent RNA helicase, is recognized as a molecular marker of germ cells and plays a crucial role in germ cell development. Silurus asotus, an important freshwater economic fish species in China, shows significant sex dimorphism with the female growing faster than the male. However, the molecular mechanisms underlying these sex differences especially involving in the vasa gene in this fish remain poorly understood. In this work, the vasa gene sequence of S. asotus (named as Savasa) was obtained through RT-PCR and rapid amplification of cDNA end (RACE), and its expression in embryos and tissues was analyzed using qRT-PCR and an in situ hybridization method. Letrozole (LT) treatment on the larvae fish was also conducted to investigate its influence on the gene. The results revealed that the open reading frame (ORF) of Savasa was 1989 bp, encoding 662 amino acids. The SaVasa protein contains 10 conserved domains unique to the DEAD-box protein family, showing the highest sequence identity of 95.92% with that of Silurus meridionalis. In embryos, Savasa is highly expressed from the two-cell stage to the blastula stage in early embryos, with a gradually decreasing trend from the gastrula stage to the heart-beating stage. Furthermore, Savasa was initially detected at the end of the cleavage furrow during the two-cell stage, later condensing into four symmetrical cell clusters with embryonic development. At the gastrula stage, Savasa-positive cells increased and began to migrate towards the dorsal side of the embryo. In tissues, Savasa is predominantly expressed in the ovaries, with almost no or lower expression in other detected tissues. Moreover, Savasa was expressed in phase I-V oocytes in the ovaries, as well as in spermatogonia and spermatocytes in the testis, implying a specific expression pattern of germ cells. In addition, LT significantly upregulated the expression of Savasa in a concentration-dependent manner during the key gonadal differentiation period of the fish. Notably, at 120 dph after LT treatment, Savasa expression was the lowest in the testis and ovary of the high concentration group. Collectively, findings from gene structure, protein sequence, phylogenetic analysis, RNA expression patterns, and response to LT suggest that Savasa is maternally inherited with conserved features, serving as a potential marker gene for germ cells in S.asotus, and might participate in LT-induced early embryonic development and gonadal development processes of the fish. This would provide a basis for further research on the application of germ cell markers and the molecular mechanisms of sex differences in S. asotus.

Quantifying Sexual Dimorphism by Analyzing Ramus Flexure and Bigonial Width in Orthopantomography.

Introduction The mandible constitutes one of the skull's largest and strongest bones. Growth spurts can influence it, and it has a variety of dimorphic traits that can be used to identify sex. In addition to observing, comparing, and evaluating the potential for mandibular ramus flexure and bigonial breadth to discriminate between sexes using digital orthopantomograms (OPG), a retrospective study was conducted to examine the validity of this method for sex estimation in the Indian population. Aim and objective This study aims to quantify sexual dimorphism by analyzing two mandibular parameters, the ramus flexure and the bigonial width, using orthopantomography (OPG). The objective is to determine the accuracy of sex determination using the ramus flexure and bigonial width. Materials and methods A total of 500 OPG images (250 males and 250 females) were analyzed using the Planmeca software (Helsinki, Finland). The ramus flexure was measured as the angle formed between the tangent to the inferior border of the mandible and the tangent to the posterior border of the ramus. The bigonial width was measured as the distance between the left and right gonion points. A statistical analysis was performed to assess sexual dimorphism and determine the accuracy of sex determination using these parameters. The study employed descriptive statistics, such as means and standard deviations, and an independent t-test to determine the significance of the characteristics in relation to males and females. Results The mean bigonial width for females was 193.3068 mm (SD = 13.51669 mm) and for males was 217.6308 mm (SD = 10.87453 mm), with a statistically significant difference (p = 0.000). The 95% confidence interval for the difference in the bigonial width between males and females was between -49.97173 mm and -43.93787 mm. For the ramus flexure, the mean was 0.0000 for both males and females (SD = 0.00000), with a significant difference between males and females (p = 0.003). The 95% confidence interval for the difference in the ramus flexure between males and females was between -0.59543 and -0.12457. Conclusion The results indicated significant sexual dimorphism in both the ramus flexure and bigonial width. This study demonstrated that the ramus flexure and bigonial width, measured using orthopantomography (OPG), exhibited significant sexual dimorphism. The analysis of these mandibular parameters provided valuable information for sex determination in forensic and anthropological contexts.

Sexual Dimorphism of Elastic Fibers in Prenatal Lung Mice

Scientific data has revealed the existence of lung gender differences and therefore sparked a renewed interest in understanding the underlying mechanisms and their effect in the healthy lung development and/or in pathological conditions. Elastic fibers have an important role in lung development during pre and post-natal stages, because a well-developed pulmonary elastic fibers favour pre-natal lung maturation and enhance alveolarization. Sexual differences studies on lung elastic fibers content are focused essentially on the post-natal stage, with scarce data on pre-natal lung development. Using an experimental mice model, we developed this research work to study gender differences in the lungs elastic fibers during gestational days E15-E19, using image analysis and elastin HPLC methodologies. Our results show significant sexual dimorphism in lung elastin and elastic fibers content pre-natal stage, which is more evident in the last two gestational days (E18 and E19). Female’s mice have more elastin and elastic fibers which could mean that the elastogenesis process begins earlier than males. These results are an important contributes to understand the underlying factors involved in physiology and lung development sexual difference.

Comparative Study of Sex Estimation by Mesiodistal width of Mandibular Canine and Mesiodistal width of Maxillary Canine in North Indian Population

Abbreviations: MD: Mesiodistal, SD: Standard deviation, mm: millimetres. Introduction: Various methods of identification such as anthropometry, stature estimation, dactylography, sex estimation, age estimation, DNA analysis, differentiation by blood groups and odontology are used in forensic medicine to create biological profile of an unknown individual. Estimation of sex is the first step towards identification of person. Determination of sex from skeletal remains is an essential task in medicolegal examination.Teeth are highly indestructible and reveal minimal turnover of natural substance hence teeth can be used for sex estimation. Mesiodistal parameter of mandibular and maxillary canine gave evidence of sex estimation due to sexual dimorphism. Aim: The aim of our study was to evaluate the sex estimation by mesiodistal width of mandibular canine and mesiodistal width of maxillary canine in north Indian population. Materials and Methods: The sample comprised of dental impression from 120 individuals (60 males and 60 females), all young adults between 20 and 35 years of age. Impressions of the teeth were made using irreversible hydrocolloid (alginate) material and casts poured in dental stone. Mesiodistal (MD) dimensions of mandibular and maxillary canine of both right and left side is measure by caliper. Results: Mean mandibular canine width of both right and left sidewere higher in male than female and were statistically significant whereas, mean maxillary canine width of both right and left side were slightly higher in male than female but were not statistically significant in young north Indian population. Left mandibular canine width (6%) was more sexually dimorphic than right mandibular canine width (5.1%). Whereas negligible sexual dimorphism shown by maxillary canine. Conclusion: The study confirmed that among maxillary and mandibular canine, mandibular canine can be used for sex estimation and shows significant sexual dimorphism.

Genetic Underpinnings of Cuticular Hydrocarbon Biosynthesis in the German Cockroach, Blattella germanica (L.): Progress and Perspectives.

Insect cuticular hydrocarbons (CHCs) serve as important waterproofing barriers and as signals and cues in chemical communication. Over the past 30 years, numerous studies on CHCs have been conducted in the German cockroach, Blattella germanica, leading to substantial progress in the field. However, there has not been a systematic review of CHC studies in this species in recent years. This review aims to provide a concise overview of the chemical composition, storage, transport, and physical properties of different CHCs in B. germanica. Additionally, we focus on the biosynthetic pathway and the genetic regulation of HC biosynthesis in this species. A considerable amount of biochemical evidence regarding the biosynthetic pathway of insect CHCs has been gathered from studies conducted in B. germanica. In recent years, there has also been an improved understanding of the molecular mechanisms that underlie CHC production in this insect. In this article, we summarize the biosynthesis of different classes of CHCs in B. germanica. Then, we review CHCs reaction to various environmental conditions and stressors and internal physiological states. Additionally, we review a body of work showing that in B. germanica, CHC profiles exhibit significant sexual dimorphism, specific CHCs act as essential precursors for female contact sex pheromone components, and we summarize the molecular regulatory mechanisms that underlie sexual dimorphism of CHC profiles. Finally, we highlight future directions and challenges in research on the biosynthesis and regulatory mechanisms of CHCs in B. germanica, and also identify potential applications of CHC studies in the pest control.

The bone marrow lipidomics of mice reveal sex-related differences.

Osteoporosis is a common skeletal disorder characterized by an imbalance between bone resorption and formation, exhibiting a higher prevalence in women compared with men. While previous studies have primarily focused on genomics and genetics in osteoporosis susceptibility, there is a lack of systematic exploration of sex-specific differences in lipid levels in mouse bone marrow. Multiple reaction monitoring-based liquid chromatography-trandem mass spectrometry(LC-MS/MS) was used to quantify lipidomic profiles in bone marrow samples from three female mice and three male mice. The LC-MS/MS technique based on the multiple reaction monitoring method identified and quantified 184 lipids from 15 lipid classes. The contents of most lipids in the bone marrow cells of female mice were higher than those in male mice, including four polyunsaturated fatty acids, three phospholipids and four sphingolipids. Among all the lipid molecules, lactosylceramide (d18:0/16:0) showed the highest fold change in female mice, while its precursor lipid, glucosylceramide, was the most up-regulated in male mice. This study, focusing on bone marrow lipidomics, elucidates significant sexual dimorphism in lipid levels within bone marrow cells. It provides novel evidence supporting the higher prevalence of osteoporosis in women and enhances our understanding of the connection between sex-specific lipid levels and the risk of osteoporosis.