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Este estudo teve como objetivo avaliar o dimorfismo sexual em uma coleção de mandíbulas portuguesas através de uma metodologia métrica digital, utilizando análise estatística descritiva, inferencial e multivariada para identificar quais parâmetros são mais dimórficos e quais são os melhores preditores de sexo. Trinta e três mandíbulas (14 mulheres e 19 homens) e pertences pessoais foram fotograficamente registrados com código e sexo. Os dados foram coletados por tomografia e as medidas foram feitas pelo software Simplant Pro. Foram registrados a largura máxima e mínima do ramo mandibular, altura condilar, altura do processo coronoide, altura da sínfise mandibular, ângulo mandibular, distâncias bimentual, biantegonial, bigonial e bicondilar e comprimento máximo mandibular. A análise estatística foi realizada utilizando IBM® SPSS. Os resultados mostraram diferenças estatisticamente significativas para os seguintes parâmetros: altura do processo coronoide, altura do côndilo, comprimento máximo da mandíbula e largura mínima do ramo mandibular. Na análise estatística multivariada foi possível identificar a altura do processo coronoide como melhor preditor de sexo com precisão em 72,2% dos casos. Isto permite uma diferenciação mais fácil entre mandíbulas femininas e masculinas com uma precisão de 64,3% e 78,9%, respectivamente. Foi possível concluir que a altura do processo coronoide é o parâmetro mais dimórfico e o melhor preditor de sexo na amostra.

This study aimed to assess sex dimorphism in a collection of Portuguese mandibles through a digital metric methodology by using descriptive, inferential, and multivariate statistical analysis to identify which parameters are the most dimorphic and which are the best sex predictors. Thirty-three mandibles (14 females and 19 males) and personal belongings were photographically registered with code and sex. Data was collected using tomography, and measurements were made using the Simplant Pro software. The maximum and minimum width of the mandibular ramus, condylar height, coronoid process height, mandibular symphysis height, mandibular angle, bi-mental, bi-antegonial, bi-gonial and bi-condylar distances, and maximal mandibular length were registered. Statistical analysis was performed using IBM® SPSS. The results showed statistically significant differences for the following parameters: coronoid process height, condyle height, the maximum length of the mandible, and the minimum width of the mandibular ramus. In the multivariate statistical analysis, it was possible to identify the coronoid process height as the best sex predictor accurately in 72.2% of cases. This allows for easier differentiation between female and male mandibles with an accuracy of 64.3% and 78.9%, respectively. It was possible to conclude that the coronoid process height is the most dimorphic parameter and the best sex predictor in the sample.

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Sex differences in metabolic dysfunction-associated steatotic liver disease (MASLD) have been reported. Oxidative stress and inflammation are involved in the progression of MASLD. Thus, we aimed to evaluate liver redox homeostasis and inflammation in male and female rats fed a high-fat diet (HFD). Male and female Wistar rats were divided into the following groups: standard chow diet (SCD) or HFD during 12 weeks. HFD groups of both sexes had higher hepatocyte injury, with no differences between the sexes. Portal space liver inflammation was higher in females-HFD compared to females-SCD, whereas no differences were observed in males. Lobular inflammation and overall liver inflammation were higher in HFD groups, regardless of sex. TNF-α, IL-6, and IL-1ß levels were higher in males-HFD compared to males-SCD, but no differences were observed in females. Catalase activity was higher in males compared to females, with no differences between the SCD and HFD groups of both sexes. Glutathione peroxidase activity was higher in females compared to males, with no differences between the SCD and HFD groups in both sexes. Lipid peroxidation was higher in female-SCD when compared to male-SCD, and in both male- and female-HFD compared to SCD groups. Furthermore, both cytoplasmic and nuclear NRF2 staining were lower in the HFD group compared to the SCD group in males. However, female-HFD exhibited reduced nuclear NRF2 staining compared to the female-SCD group. In conclusion, our study demonstrated that while both male and female rats developed metabolic dysfunction-associated steatohepatitis after 12 weeks of HFD, the alterations in inflammatory cytokines and redox balance were sexually dimorphic.

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Chronic pain is the most disability symptom related to multiple sclerosis (MS) brain lesions and can also generate anxiety and depression. There are no updated reports of the general prevalence of neuropathic pain, MS clinical types, sex dimorphism, and its association with depression and anxiety. The protocol was listed in PROSPERO (CRD42022303571). The article selection resulted in 24 studies with a low risk of bias. The prevalence of neuropathic pain in MS patients was 26.8% with higher levels of depression and anxiety. We also observed that female patients (74.2%) have a higher prevalence of neuropathic pain than males (28.9%). We showed the enhanced prevalence of neuropathic pain using the female and male data (58.9%) compared to the total prevalence (26.8%). In addition, the SPMS (40.3%) presented an increased prevalence of neuropathic pain compared to PPMS (15.6%). Thus, we demonstrated the association between neuropathic pain, depression and anxiety symptoms and the influence of diagnosis, age, disease score, and disease duration in the increased prevalence of neuropathic pain in MS patients.

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Neurocysticercosis is a heterogeneous disease, and the patient's sex seems to play a role in this heterogeneity. Hosts' sexual dimorphism in cysticercosis has been largely explored in the murine model of intraperitoneal Taenia crassiceps cysticercosis. In this study, we investigated the sexual dimorphism of inflammatory responses in a rat model of extraparenchymal neurocysticercosis caused by T. crassiceps. T. crassiceps cysticerci were inoculated in the subarachnoid space of Wistar rats (25 females, 22 males). Ninety days later, the rats were euthanized for histologic, immunohistochemistry, and cytokines studies. Ten animals also underwent a 7-T magnetic resonance imaging (MRI). Female rats presented a higher concentration of immune cells in the arachnoid-brain interface, reactive astrogliosis in the periventricular region, in situ pro-inflammatory cytokine (interleukin [IL]-6) and anti-inflammatory cytokine (IL-10), and more intense hydrocephalus on MRI than males. Intracranial hypertension signals were not observed during the observational period. Overall, these results suggest sexual dimorphism in the intracranial inflammatory response that accompanied T. crassiceps extraparenchymal neurocysticercosis.

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Hypothyroidism is an endocrine-metabolic disorder, and as such it compromises a wide range of physiological functions. Memory deficits and, the most recently described, circadian rhythm disruption are among the impairments caused by thyroid dysfunctions. However, although highly likely, there is no evidence connecting these two effects of hypothyroidism. Here, we hypothesized the time-of-day interferes with the memory deficit caused by hypothyroidism. C57BL/6 J mice from both sexes were subjected to novel object recognition (NOR) task during the rest and active phases, corresponding to ZT 2-4 and 14-16, respectively (ZT: Zeitgeber time; ZT 0: lights on at 07:00 am). First, we showed that neither sex nor ZT altered object recognition memory (ORM) in euthyroid mice. Next, animals were divided into control (euthyroid) and hypothyroid [induced with methimazole (0.01%) and perchlorate (0.1%) treatment in the drinking water for 21 days] groups. Under euthyroid conditions, male and female mice recognized the novel object regardless of the time-of-day. However, hypothyroidism impaired ORM at rest phase (ZT 2-4) in both sexes. Surprisingly, in the active phase (ZT 14-16), the hypothyroid males performed the NOR, though a longer time to execute the task was required. In contrast, female hypothyroid mice showed a greater impairment in ORM. Our results suggest that hypothyroidism may disrupt the circadian rhythm in brain areas related to mnemonic processes since in euthyroid condition ORM is not affected by the time-of-day. Furthermore, our findings in an animal model indicate a pronounced deleterious effect of hypothyroidism in women.

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BACKGROUND: Maternal obesity (MO) is associated with a higher risk of immune-mediated diseases in the offspring and higher leptin levels in cord blood (CB). This study evaluates the number and function of lymphocyte subtypes in CB related to MO and its relationship with leptin concentration and leptin receptor expression. METHODS: Pregnant women with (n = 32) or without obesity (n = 41) were enrolled at delivery. Cord blood mononuclear cells were separated with Ficoll-Hypaque. B and CD4+, regulatory and effector T cells were quantified by Flow Cytometry. Cord blood leptin concentration was measured by ELISA, and the leptin receptor (sLepR) on Treg cells was determined by Flow Cytometry. RESULTS: MO was associated with higher numbers of CD4+, Treg and effector T cells in the CB of their offspring, without differences in the suppressive function of Tregs. Female offspring had a higher number of these cells and a higher cord leptin concentration. Tregs expressed higher levels of sLepR than effector T cells, without differences between groups. CONCLUSIONS: MO is associated with changes in the newborn's immune profile, more evident in female newborns with higher leptin concentrations. More studies are needed to identify the mechanisms by which the high levels of cord leptin in the newborn of women with obesity could affect the offspring's immune system.

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Previous studies on the cardiac data of healthy permanent residents living in high-altitude regions such as Tibet and the Andes have yielded inconsistent findings and significant disparities. These discrepancies can be mainly attributed to the invasive methods conventionally used for parameter evaluation. However, with the introduction of cutting-edge ultrasound technology, there is now an innovative approach to addressing and reconciling these variations. In this pilot study, we employed an ultrasound-based cardiac output monitoring (USCOM) device to evaluate cardiac output and related hemodynamic variables in a group of 20 healthy high-altitude Andean residents (comprising 10 men and 10 women) aged between 26 and 35 years old. The monocentric study was carried out in La Paz, Bolivia, located between at an altitude of 3,600-4,000 m. A total of 60 hemodynamic measurements were evaluated, accounting for three technical replicates per subject. Our results showed strong intrasubject reproducibility and revealed important differences related to both sex and hemodynamic parameters in highlanders compared to individuals residing at sea level. We conclude that USCOM represents a highly reliable technology for performing hemodynamic measurements in high-altitude residents. Our preliminary findings underscore the need for larger studies, encompassing larger sample sizes, specifically tailored to gender considerations, and extendable to broader highland populations. These findings have special significant implications for the management of hemodynamics in intensive care and postoperative settings, warranting further comprehensive research efforts.

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Background: The evaluation of vertical kneecap position within the trochlear groove is essential for understanding the anatomical changes that may lead to canine patellar luxation. Unlike other important diagnostic imaging measurements (e.g. measures of pelvic limb alignment), no data on patellofemoral congruence parameters of canine stifles (congruence angle, linear axial patellar displacement, lateral patellofemoral angle, patellar tilt angle) are reported. The aim of this study was to present metric values of these parameters in healthy dogs from small breeds from both sexes in order to use them for identification of animals with increased risk for medial patellar luxation. Materials, Methods & Results: The study was performed on 44 stifle joints from 22 healthy dogs of both sexes from 4 small breeds (Pinscher, Pomeranian, Chihuahua and Yorkshire terrier). Inclusion criteria were negative patellar displacement and dancing patella tests after orthopaedic examination, lack of femoral and gluteal muscles asymmetry after palpation, lack of signs of long-term proprioceptive dysfunction, normal patellar and withdrawal reflexes after neurological examination. The translation of the patella in the axial plane was evaluated by means of congruence angle and axial linear patellar displacement. The rotation of the patella in the axial plane was evaluated through measurement of lateral patellofemoral angle and patellar tilt angle. Reference ranges of parameters were analysed in agreement with the guidelines of the American College of Veterinary Pathologists for the determination of reference intervals in veterinary species for sample sizes of 40-120 with non-Gaussian distribution - robust method, 95% confidence interval (CI) with 90 % CI for upper and lower reference limits. All measured patellofemoral congruence angles were negative. Their reference range was from -8.06o to -0.58o (median value -3o ). The axial patellar displacement was negligible, with values ranging from 0.1 to 0.8 mm. Lateral patellofemoral angles in all dogs were open to the lateral side (positive); the computed reference interval was from 21.61o to 41.80o (median 31.5o ). Patellar tilt angles ranged from 2o to 8o (median 5o ). A statistically significant difference between sexes was demonstrated for angles describing the rotation of the patella in the axial plane: the lateral patellofemoral angle (P = 0.0248) and the patellar tilt angle (P = 0.0004) were greater in stifles of male dogs. Discussion: This is the first study presenting reference values of parameters describing patellofemoral alignment in healthy dogs from small breeds on tangential radiographs. The values of one of most commonly measured parameters on tangential radiographs (the lateral patellofemoral angle) in stifles of small breed dogs were higher than values in humans, supposedly due to the specific joint anatomy. The patellar tilt angle is considered as more objective and not influenced by limb rotation. For the detection of patellar misalignment, the tilt angle was reported to be almost as specific as the congruence angle but more sensitive and more accurate. It is the most specific and sensitive parameter determining the direction of patellar luxation. In male dogs, the median lateral patellofemoral angle was greater than in females (P = 0.0248). Similar tendency was shown for patellar tilt angle that was also greater in male stifles (P = 0.0004). The reported statistically significant between-sex differences in lateral patellofemoral angle and patellar tilt angle with higher values of both angles in stifles of male dogs could be attributed to the better developed femoral muscles, in particular m. vastus medialis and m. sartorius, and to differences in trochlear groove and kneecap morphology. The presented reference intervals may be useful for early detection of subjects with increased risk to medial patellar luxation.

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The hypothalamus-pituitary-thyroid-axis (HPT) is one of the main neuroendocrine axes that control energy expenditure. The activity of hypophysiotropic thyrotropin releasing hormone (TRH) neurons is modulated by nutritional status, energy demands and stress, all of which are sex dependent. Sex dimorphism has been associated with sex steroids whose concentration vary along the life-span, but also to sex chromosomes that define not only sexual characteristics but the expression of relevant genes. In this review we describe sex differences in basal HPT axis activity and in its response to stress and to metabolic challenges in experimental animals at different stages of development, as well as some of the limited information available on humans. Literature review was accomplished by searching in Pubmed under the following words: "sex dimorphic" or "sex differences" or "female" or "women" and "thyrotropin" or "thyroid hormones" or "deiodinases" and "energy homeostasis" or "stress". The most representative articles were discussed, and to reduce the number of references, selected reviews were cited.

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High-fat diet (HFD) feeding or leptin-deficient mice are extensively used as models resembling features of human nonalcoholic fatty liver disease (NAFLD). The concurrence of experimental factors as fat content and source or total caloric intake leads to prominent differences in the development of the hepatic steatosis and related disturbances. In this work, we characterized the hepatic lipid accumulation induced by HFD in wild-type (WT) and ob/ ob mice with the purpose of differentiating adaptations to HFD from those specific of increased overfeeding due to leptin deficiency-associated hyperphagia. Given that most published works have been done in male models, we used female mice with the aim of increasing the body of evidence regarding NAFLD in female subjects. HFD promoted liver lipid accumulation only in the hyperphagic strain. Nevertheless, a decrease of lipid droplet-associated cholesteryl ester (CE) in both WT and obese animals was observed. These changes were accompanied by an improvement in the profile of lipoproteins that transport cholesterol and liver function markers in plasma from ob/ ob mice and a lower hepatic index. Using primary hepatocytes from female mice, overaccumulation of CE induced by 0.4 mM oleic acid reversed in the presence of a specific Takeda G protein-coupled bile acid receptor agonist. Nevertheless, hepatocytes from male mice were not responsive. This study suggests that enterohepatic circulation of bile acids might be one of the factors that can affect sex dimorphism in NAFLD development, which underlines the importance of including female models in the NAFLD research field. NEW & NOTEWORTHY This work provides new insight into the use of high-fat diet as a model to induce nonalcoholic fatty liver disease in wild-type and ob/ ob female mice. We show that high-fat diet induces steatosis only in ob/ ob mice while, surprisingly, several health indicators improve. Noteworthy, experiments with primary hepatocytes from male and female mice show that they express Takeda G protein-coupled bile acid receptor and that it and bile acid enterohepatic circulation might be accountable for sex dimorphism in nonalcoholic fatty liver disease development.

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The present study was planned to improve our understanding about sex differences in the development of hepatic steatosis in cafeteria diet-induced obesity in young mice. Female (FCaf) and male (MCaf) mice fed a cafeteria diet had similar body weight gain and adiposity index, but FCaf had a more extensive steatosis than MCaf. FCaf livers exhibited a higher non-alcoholic fatty liver disease activity score, elevated lipid percentage area (+34%) in Sudan III staining and increased TG content (+25%) compared to MCaf. Steatosis in FCaf was not correlated with changes in the transcript levels of lipid metabolism-related genes, but a reduced VLDL release rate was observed. Signs of oxidative stress were found in FCaf livers, as elevated malondialdehyde content (+110%), reduced catalase activity (-36%) and increased Nrf2 and Hif1a mRNA expression compared to MCaf. Interestingly, fibroblast growth factor 21 (Fgf21) mRNA expression was found to be exclusively induced in MCaf, which also exhibited higher FGF21 serum levels (+416%) and hepatic protein abundance (+163%) than FCaf. Moreover, cafeteria diet increased Fgfr1, Fsp27 and Ucp1 mRNA expression in brown adipose tissue of males (MCaf), but not females (FCaf). FGF21 hepatic production by male mice seems to be part of a complex network of responses to the nutritional stress of the cafeteria diet, probably related to the unfolded protein response activation. Although aimed at the restoration of hepatic metabolic homeostasis, the branch involving Fgf21 upregulation seems to be impaired in females, rendering them incapable of reducing the hepatic lipid content and cellular oxidative stress.

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In humans, complementary feeding should be started after 6 months-old; the introduction of any food or water before this time is considered early weaning, which is associated with health problems in adulthood. Cow's milk is a common food introduced to children less than 6 months that has inadequate nutritional composition mainly due to a worse casein: whey protein ratio compared to human milk. We hypothesized that suckling rats fed with cow's milk, rich in bioactive peptides, develop further metabolic dysfunctions. From postnatal day (PN) 14 to 20, Wistar rat pups were divided into 3 groups: rat milk (RM) - pups received rat milk orally in a syringe; cow's milk (CM), pups received cow's milk; CM with high protein (CM-H), CM with twice protein amount of rat milk. Pups were killed on PN21 and PN180. At PN21, CM males had lower visceral fat mass compared with other groups. Serum corticosterone was higher in CM-H males, despite no change in glucocorticoid metabolism in liver and visceral fat. At PN180, CM and CM-H females had greater fat depots and hyperphagia, although no alteration in leptinemia and leptin signaling in hypothalamus. CM-H females had a trend of hypoinsulinemia and significant decrease in HOMA-ß, suggesting lower insulin secretion. Males from CM-H group had only lower total body protein mass. CM males had hypercorticosteronemia associated with lower expression of 11ßHDS1 in visceral fat. In conclusion, early introduction of cow's milk in neonate rats leads to gender-dependent differences in metabolic and endocrine parameters in the short- and long-term.

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Objective: The present study aimed to investigate the potential of permanent canines for sexual dimorphism in a Brazilian population. Methods: The sample consisted of 172 dental casts from females (n=102) and males (n=70) aged between 13 and 49 years old. Each dental cast underwent mesiodistal (MD) and buccolingual (BL) measurement of the permanent canines using a digital caliper and a bow compass. MD and BL dimensions were compared between sex groups using Student's t-test for independent samples. Results: Statistically significant differences were observed comparing the odontometric information between females and males (p<0.05). Conclusion: These findings indicate that permanent canines have metric characteristics to enable sexual dimorphism, becoming useful for Brazilian forensic services.

Objetivo: O presente estudo objetivou avaliar o potencial de caninos permanentes para dimorfismo sexual aplicado à prática forense. Métodos: A amostra consistiu de 172 modelos de gesso odontológicos de pacientes do sexo feminino (n=102) e masculino (n=70) de idades entre 13 e 49 anos. Cada modelo odontológico foi submetido à mensuração dos diâmetros mesiodistal (MD) e bucolingual (BL) utilizando um paquímetro digital e um compasso de ponta seca. Os valores obtidos para cada diâmetro foram comparados entre sexos por meio do teste T de Student para amostras independentes. Resultados: Diferenças com significância estatística foram observadas comparando os achados obtidos para os sexos feminino e masculino (p<0.05). Conclusão: Estes resultados indicam que os caninos permanentes apresentam características morfométricas capazes de diferenças sexos, sendo uma ferramenta útil para os serviços de Odontologia e Antropologia Forense do Brasil.

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The development of the prostate gland in females has not yet been clearly elucidated, and the sexual dimorphism associated with such gland development in general is far from being understood. In the present study, we used tridimensional (3D) reconstructions and histochemical and immunohistochemical techniques to describe the sexual dimorphism and its causes in the early postnatal development of the prostate in male and female Mongolian gerbils (Meriones unguiculatus). We observed that the female prostate was smaller, had fewer branches throughout the development, and underwent differentiation earlier than that in males. Also, the expression of the estrogen receptor 1 (ESR1 or ER-alpha) and fibroblast growth factor 10 (FGF10) was decreased in the periductal region, and the expression of the androgen receptor (AR) was increased in the epithelium. All together, these changes decreased proliferation and branching and led to an earlier prematuration of the female prostate. These new data shed light on the underlying mechanisms involved with the sexual dimorphism in the development of the prostate. Anat Rec, 299:1130-1139, 2016. © 2016 Wiley Periodicals, Inc.

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The present study investigated the validity of mandibular ramus flexure in sex differentiation among young Jordanian adults using Orthopantomographic images in a double blind study. A normative sample comprised of 419 images was selected, of which 126 belonged to male patients and 293 images to females. The exclusion criteria used in the selection involved excluding images that showed marked loss of mandibular molars, over erupted, tilted, anomalous molars and teeth or mandibles associated with pathology. Each image was examined for the presence of a flexure on the posterior margin of the ramus at the occlusal plane. The posterior margin of the ramus was carefully traced graphically and the occlusal plane level was delineated as guided by the height of cusp tips at the occlusal surfaces of the mandibular molars. The ramus flexure was more accurately diagnostic for females (94.6%), than for males (47.6%); this gave rise to an overall diagnostic accuracy of 70.9% which is far below the reported 90.6-99.0% by Loth & Henneberg. Our results, however, agreed with some reported findings of other researchers. In conclusion, ramus flexure provides a moderately acceptable predictive accuracy and could be considered as a supplementary rather than a definitive mean of sex determination. In sexing unknown skeletal remains, it is necessary to employ as many methods or traits as possible instead of relying on one morphological trait.

El presente estudio investigó la validez de flexura de la rama mandibular en la diferenciación sexual entre adultos jóvenes jordanos utilizando imágenes de ortopantomografías, en un estudio doble ciego. Se seleccionó una muestra normativa compuesta de 419 imágenes, de las cuales 126 pertenecían a hombres y 293 a mujeres. Se excluyeron imágenes que mostraron una pérdida marcada de los molares mandibulares, dientes sobre erupcionados o inclinados, molares anómalos y los dientes o mandíbulas con enfermedad. Cada imagen fue examinada para detectar la presencia de un ángulo en el margen posterior de la rama en el plano oclusal. El margen posterior de la rama mandibular fue trazado gráficamente y el plano oclusal se delineó estableciendo como guía la altura de las puntas cuspídeas en las superficies oclusales de los molares mandibulares. La flexura de la rama mandibular fue más precisa en el diagnóstico de las mujeres (94,6%) que para los hombres (47,6%); con una precisión diagnóstica global del 70,9%, la cual es inferior a la reportada por Loth & Henneberg entre 90,6­99,0%. Nuestros resultados, concuerdan con algunos hallazgos reportados por otros investigadores. En conclusión, la flexura de la rama mandibular proporciona una exactitud de predicción moderadamente aceptable y podría ser considerada como un complemento en lugar de un medio definitivo de la determinación del sexo. En restos óseos desconocidos, es necesario emplear la mayor cantidad de métodos o rasgos posibles que depender de un solo rasgo morfológico.

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The water-hyacinth grasshopper Cornops aquaticum (Bruner) (Orthoptera: Acrididae) is native to South America and inhabits lowlands from southern Mexico to central Argentina and Uruguay. This grasshopper feeds and lays eggs on species from the genera Eichhornia and Pontederia. Particularly, Eichhornia crassipes is considered "the world's worst water weed," and the release of C. aquaticum was proposed as a form of biological control. Morphometric variation on the chromosomally differentiated populations from the middle and lower Paraná River and its possible association with geographic, sex, and chromosomal conditions was analyzed. Significant phenotype variation in C. aquaticum population was detected. C. aquaticum presents body-size sexual dimorphism, females being bigger than males. Female-biased sexual size dimorphism for all five analyzed traits was detected. The assessment of variation in sexual size dimorphism for tegmen length showed that this trait scaled allometrically, indicating that males and females did not vary in a similar fashion. The detected allometry was consistent with Rensch's rule demonstrating greater evolutionary divergence in male size than in female size and suggests that males are more sensitive to environmental condition. The analysis of morphometric variation in the context of chromosome constitution showed that the presence of fusion 1/6 was related to body-size variation. Fusion carriers displayed bigger body size than standard homozygotes. Besides, a positive relationship between tegmen length and the number of fused chromosomes was detected, showing a chromosome dose effect. Because the highest frequency of fusions has been found in the lower Paraná River, a marginal environment for this species, the results found would support the hypothesis that some supergenes located in the fusions may be favored in the southern populations, thus contributing to the establishment and maintenance of the polymorphism.

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El objetivo de esta investigación fue determinar diferencias de dimorfismo sexual de las características de labios de hombre y mujeres mestizos colombianos a través de análisis fotogramétrico. Se evaluaron fotografías frontales de 120 individuos mestizos sin alteraciones congénitas o adquiridas de los labios, tomadas en relación 1:1. A través del uso de puntos antropométricos en la vista frontal, se evaluaron las dimensiones: grosor del labio superior (Sn-Stms), grosor del bermellon superior (Stms-Ls), grosor del labio inferior (Stmi-Sml), grosor del bermellon inferior (Stmi-Li) y ancho bicomisural (Chd-Chi), con la ayuda del software J image (NIH). El análisis estadístico utilizó la prueba U Mann-Whitney usando el software SPSS 17.0, para determinar diferencias entre los dos sexos en todas las variables. No se encontraron diferencias estadísticamente significativas en la longitud del bermellón del labio superior (Stms-Ls) ni en la longitud del bermellón del labio inferior (Stmi-Li). Se encontraron diferencias estadísticamente significativas (p<0,001) en grosor del labio superior (Sn-Stms), grosor del labio inferior (Stmi-Sml) y ancho bicomisural (Chd-Chi). Estas medidas fueron mayores en individuos mestizos de género masculino. Existe dimorfismo sexual en el ancho bicomisural, longitud de labio superior e inferior en colombianos mestizos.

The aim of this research was to determine sexual dimorphism in lip characteristic in colombian male and female population through a photogrammetric study. Frontal facial photographs, in 1 to 1 scale, from 120 colombian persons without congenital or acquired lip alterations were evaluated. Using frontal landmarks, longitudinal dimensions of upper lip height (Sn-Stms), vermilion height of the upper lip (Stms-Ls), lower lip height (Stmi-Sml), vermilion height of the lower lip (Stmi-Li) and mouth width (ch-ch). J image software was user for phogrammetric analysis (NIH). For stadistical analysis U mann-whitney test was used with SPSS 17.0, in order to determine sexual dimorphism in lip characteristic. No significant sexual dimorphism was found for vermilion height of the upper lip (Stms-Ls) nor vermillion height of the lower lip (Stmi-Li). Significan sexual dimorphism was found for upper lip height (Sn-Stms), lower lip height (Stmi-Sml) and mouth width (ch-ch). All longitudinal measurements were larger in male than female. There was sexual dimorphism in lip measurements in a colombian population, when evaluated using phoptogrammetric methods.

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