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1.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 38(11): 1123-1126, 2021 Nov 10.
Artigo em Chinês | MEDLINE | ID: mdl-34729757

RESUMO

OBJECTIVE: To explore the genetic basis for a child with 46,XY disorders of sex development (DSD) and explore its genotype-phenotype correlation. METHODS: The child was subjected to whole exome sequencing (WES), and exons 1 to 7 of NR5A1 were subjected to multiplex ligation-dependent probe amplification (MLPA) analysis. RESULTS: The patient presented with rudimentary vulva of a female with Tanner stage 1. B-mode ultrasonography has detected ovary and uterus. The child was found to have a chromosome karyotype of 46,XY. WES revealed that the patient has harbored heterozygous deletion of exon 5 of the NR5A1 gene, which was a novel pathogenic variant inherited from the mother. No abnormality was found in the father. CONCLUSION: The main symptoms of 46,XY DSD children are insufficient external genitalia masculinization, for which variants of the NR5A1 gene are an important cause. WES has improved the detection rate of genetic variants and provided a solid basis for genetic counseling of the affected families.


Assuntos
Transtorno 46,XY do Desenvolvimento Sexual , Transtornos do Desenvolvimento Sexual , Criança , Transtorno 46,XY do Desenvolvimento Sexual/genética , Transtornos do Desenvolvimento Sexual/genética , Éxons/genética , Feminino , Testes Genéticos , Heterozigoto , Humanos , Mutação , Fator Esteroidogênico 1/genética
2.
J Hist Dent ; 69(2): 132-133, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34734796

RESUMO

James Washington Bartlett (1839-1910, FAG Memorial #124715057) was born in Derby Line, Orleans County, Vermont to Nathaniel Bartlett (1791-1866), a harness maker, and Martha Pinkham Bartlett (1798-1847). Little is known about his youth nor his education. He was evidently preceptor trained in dentistry but we were unable to determine with whom.


Assuntos
Cardiologia , Transtornos do Desenvolvimento Sexual , Adolescente , Humanos , Masculino , Publicações , Vermont , Washington
3.
Zoolog Sci ; 38(5): 416-426, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34664916

RESUMO

Although many animals that perform sexual reproduction exhibit sexual dimorphism, individuals with intersex traits between the traits of males and females appear in some species, depending on environmental factors. Ptychognathus ishii, a varunid crab, exhibits distinctive sexual dimorphism in the morphology of its abdomen, chelipeds and setal tufts on the chelipeds. In this study, however, we report for the first time that intersex individuals with intermediate characters between those of males and females were occasionally found in wild populations. Morphological features of intersex individuals are described. Their taxonomic positions are identified based on DNA sequences of part of the mitochondrial cytochrome c oxidase I (COI) gene. It was shown that the intersexuality was induced by entoniscid parasites, because all intersex individuals were parasitized by entoniscid isopods, identified as Entionella sp. The apparent correlation between parasitism and morphological anomalies suggests that the parasitic isopods affect physiological conditions, leading to the feminization of male hosts.


Assuntos
Braquiúros/parasitologia , Transtornos do Desenvolvimento Sexual/parasitologia , Caracteres Sexuais , Animais , Braquiúros/anatomia & histologia , Braquiúros/genética , Feminino , Isópodes/classificação , Masculino , Análise de Sequência de DNA
4.
Zhonghua Bing Li Xue Za Zhi ; 50(10): 1145-1150, 2021 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-34619868

RESUMO

Objective: To investigate the clinicopathological features of gonadal neoplastic related lesions in children with disorders of sexual development (DsD). Methods: The clinical manifestations, chromosomal karyotype, histology and immunophenotype of 12 cases of neoplastic related lesions from Guangzhou Women and Children's Medical Center, Guangzhou were analyzed during Jan 2015 to May 2020. Results: Twelve cases of neoplastic related lesions were screened in 205 cases of DsD, and 6 patients with gonadal germ cell neoplasia aged 3-13 years with an average age of 8.3 years. There were 2 males and 4 females. Clinical features showed malformation of external genitalia in 2 cases, short stature in 2 cases, clitoral enlargement in 1 case, lower abdominal pain and a huge pelvic mass in 1 case. Chromosomal karyotyping of peripheral blood showed 2 cases of 46XY and 4 cases of 45X/46XY. Fourteen gonadal specimens were examined. Microscopically, 1 case showed dysgerminoma in left ovary, and malignant mixed germ cell tumors in right ovary, as well as gonadoblastoma (GB) and undifferentiated gonadal tissue (UGT). The remaining 5 cases were all precursor lesions of germ cell tumor. Six specimens showed GB, 3 of UGT, and 3 specimens showed germ cell neoplasia in situ (GCNIS), one of which was accompanied by intratubular seminoma and 1 was GB with GCNIS. The other 6 patients with DsD were aged from 8 months to 2 years and 5 months, including 5 males and 1 females. Clinical manifestations showed 5 cases of hypospadias and 1 case of bilateral indirect inguinal hernia. Microscopically, 6 cases showed maturation delay of gonocytes in seminiferous tubules. Immunohistochemically, the primordial germ cells/gonocytes expressed OCT3/4, PLAP and c-KIT in the 12 cases. Conclusion: Gonadal neoplasia in children with DsD is mainly precursor lesions of germ cell tumor and improved understanding of these lesions is of great significance.


Assuntos
Transtornos do Desenvolvimento Sexual , Gonadoblastoma , Neoplasias Embrionárias de Células Germinativas , Neoplasias Ovarianas , Neoplasias Testiculares , Criança , Feminino , Gonadoblastoma/genética , Gonadoblastoma/cirurgia , Humanos , Masculino
5.
Orphanet J Rare Dis ; 16(1): 416, 2021 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-34627348

RESUMO

BACKGROUND: 46, XY disorders of sex development (46, XY DSD) are congenital disorders with 46, XY chromosomal karyotype but inconsistent gonadal/phenotypic sex. One of the biggest concerns for parents and clinicians is the gender assignment. However, there is no standard uniform of care nor consensus at present. We sought to evaluate the current treatment's rationality and provide a reference basis for the gender reassignment in 46, XY DSD patients with a specific diagnosis. METHODS: We conducted a cross-sectional survey of gender role with the Pre-school Activities Inventory (PSAI), the Children's Sex Role Inventory (CSRI) in 46, XY DSD patients and set up control groups comparison. Psychiatrist assessed gender dysphoria in patients ≥ 8-year-old with the criteria of diagnostic and statistical manual of mental disorders, 5th edition (DSM-5). RESULTS: A total of 112 responders of 136 patients participated in this study (82.4%, aged 2-17.8 years, median age: 4-year-old). The follow-up period was from 6 months to 10 years (median: 2 years). Twenty-five females were reassigned to the male gender after a specific diagnosis (16/25 (64%) in 5 alfa-reductase-2 deficiency (5α-RD2), 5/25 (20%) in partial androgen insensitivity syndrome (PAIS), 4/25 (16%) in NR5A1gene mutation). Male gender assignment increased from 55.3 (n = 62) to 77.7% (n = 87). The median PSAI score was similar to the control males in 5α-RD2, PAIS, and NR5A1 gene mutation groups (p > 0.05); while identical to the control females in complete androgen insensitivity syndrome (CAIS) and CYP17A1 gene mutation groups (p > 0.05). PSAI score of children raised as male was higher than those of CAIS and CYP17A1 groups raised as female (p < 0.05). CSRI scale showed no statistical differences in the consistency of gender roles and reassigned gender between 46, XY DSD patients and control groups (p > 0.05). None of the patients over 8-year-old (n = 44) had gender dysphoria. CONCLUSION: The reassigned gender in 46, XY DSD patients is consistent with their gender role during early childhood. None of them had gender dysphoria. The molecular diagnosis, gonadal function, and the gender reassignment are congruent within our Chinese cohort. Long-term follow-up and more evaluation are still required.


Assuntos
Transtorno 46,XY do Desenvolvimento Sexual , Transtornos do Desenvolvimento Sexual , Disforia de Gênero , Criança , Pré-Escolar , Estudos Transversais , Transtorno 46,XY do Desenvolvimento Sexual/diagnóstico , Transtorno 46,XY do Desenvolvimento Sexual/genética , Transtornos do Desenvolvimento Sexual/diagnóstico , Transtornos do Desenvolvimento Sexual/genética , Feminino , Disforia de Gênero/diagnóstico , Disforia de Gênero/genética , Papel de Gênero , Humanos , Masculino
6.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 38(9): 912-916, 2021 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-34487543

RESUMO

MAMLD1 gene has been implicated in 46,XY disorders of sex development (DSD) in recent years. Patients carrying MAMLD1 gene variants showed a "continuous spectrum" of simple micropenis, mild, moderate and severe hypospadias with micropenis, cryptorchidism, split scrotum and even complete gonadal dysplasia. The function of MAMLD1 gene in sexual development has not been fully elucidated, and its role in DSD has remained controversial. This article has reviewed recent findings on the role of the MAMLD1 gene in DSD, including the MAMLD1 gene, its encoded protein, genetic variants, clinical phenotype and possible pathogenic mechanism in DSD.


Assuntos
Proteínas de Ligação a DNA , Transtornos do Desenvolvimento Sexual , Proteínas de Ligação a DNA/genética , Transtornos do Desenvolvimento Sexual/genética , Humanos , Masculino , Mutação , Proteínas Nucleares/genética , Fenótipo , Desenvolvimento Sexual , Fatores de Transcrição/genética
7.
Pediatr Ann ; 50(9): e359-e365, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34542337

RESUMO

Throughout the history of Western culture, sex has been reflected as a binary rule, with this binary system affecting self-expression, lifestyle choices, and health outcomes of everyone, but especially those with intersex traits. "Intersex" (or differences of sex development) is an umbrella term used to describe a wide range of natural variations in genitalia, gonads, and chromosome patterns that do not fit typical binary notions of male or female bodies. Currently, people who identify as intersex or as having intersex traits are not provided with the appropriate care needed for their wellbeing. Intersex health care has undergone a great deal of change in the last century, led by intersex leaders and advocates. Clinician advocates have also played a vital role. This article will focus on this history of intersex health care evolution, the role of clinician advocacy, and suggestions for how clinicians can become advocates for improving intersex health care. [Pediatr Ann. 2021;50(9):e359-e365.].


Assuntos
Atenção à Saúde/tendências , Transtornos do Desenvolvimento Sexual , Transtornos do Desenvolvimento Sexual/diagnóstico , Transtornos do Desenvolvimento Sexual/terapia , Feminino , Gônadas/anatomia & histologia , Humanos , Masculino , Defesa do Paciente , Papel do Médico
8.
AMA J Ethics ; 23(7): E550-556, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34351265

RESUMO

For years, physicians have debated how best to care for children with differences in sex development (DSD, also termed intersex). Stories of suffering of adults who underwent early surgical intervention for DSD have led many health organizations to call for deferral of unnecessary procedures. While some have instituted full deferral of cosmetic procedures, standard of care remains an interdisciplinary team approach informed by parents' wishes. As the medical community hesitates to institute full deferral, citing absence of long-term data, legislation restricting early procedures is mounting. This article highlights recent data from the DSD-LIFE Study and considers whether and to what extent they support deferral.


Assuntos
Transtornos do Desenvolvimento Sexual , Médicos , Adulto , Criança , Humanos , Pais , Desenvolvimento Sexual , Padrão de Cuidado
10.
Semin Pediatr Surg ; 30(4): 151078, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34412885

RESUMO

Differences/disorders of sex development (DSD) are a heterogeneous group of congenital conditions in which the development of chromosomal, gonadal, or anatomical sex is atypical. Patients usually present during the newborn period but occasionally some cases remain unrecognized until later in infancy or even adolescence. Genital appearance, psychosocial support, sociocultural background, gender identity development, and genetic and biochemical analysis in addition to ethical and legal implications need to be considered when deciding on the appropriate treatment strategy. Surgeons are important members of the multidisciplinary expert teams involved in the initial approach and long-term follow-up. Surgical care of DSD patients is one of the main challenges. Recommendations regarding the opportunity and timing of surgical procedures are still under discussion. Surgical procedures are aimed to reduce urologic problems, prevent the risk of gonadal germ-cell cancer, and facilitate sexual function and reproduction. Providing its excellent visualization, access to pelvic structures and less postoperative adhesion MIS has been an important tool in the diagnosis and treatment of DSD. The role of MIS will be summarized in: 1) Gonadal biopsy / gonadectomy 2) Treatment of urogenital sinus/vaginoplasty 3) Vaginal Replacement 4) Resection / treatment of Mullerian structures.


Assuntos
Transtornos do Desenvolvimento Sexual , Neoplasias Embrionárias de Células Germinativas , Transtornos do Desenvolvimento Sexual/diagnóstico , Transtornos do Desenvolvimento Sexual/cirurgia , Feminino , Identidade de Gênero , Humanos , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos , Desenvolvimento Sexual
11.
J Equine Vet Sci ; 104: 103692, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34416985

RESUMO

A 4-year-old Straight Egyptian Arabian horse was evaluated in 2016 due to a malformation of external genitalia and male sexual behavior. On physical examination, small teats in the inguinal area and a rudimentary penis-like structure surrounded by a clitoral fossa could be seen. There was no evidence of vulva and vaginal canal. A stallion like behavior was observed, especially in the presence of mares in heat, when the animal was excited and aggressive and had erection of the penis-like structure. Blood samples were collected for two purposes: hormonal (testosterone and estradiol plasma concentration analyses) and genetic (cytogenetic and molecular analysis). The karyotype showed 32 pairs of chromosomes in all cells (2n = 64) including 14 and 18 pairs of metacentric and acrocentric chromosomes respectively, in agreement with a presumptive 64, XX complement. This result agree with STR and SNP molecular analysis, which also ruled out the possibility of hematopoietic chimerism. In addition, SNP genotyping showed no numerical chromosomal aberrations or large deletions or duplications, that can be linked to the phenotype in any autosome, nor numerical chromosomal abnormalities in the father and mother of the horse analyzed. In conclusion, we determined that the animal in the present study is a male pseudohermaphrodite.


Assuntos
Transtornos do Desenvolvimento Sexual , Doenças dos Cavalos , Animais , Transtornos do Desenvolvimento Sexual/diagnóstico , Transtornos do Desenvolvimento Sexual/veterinária , Egito , Feminino , Genômica , Doenças dos Cavalos/diagnóstico , Cavalos , Cariótipo , Cariotipagem/veterinária , Masculino
12.
J Sex Med ; 18(10): 1797-1806, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34419416

RESUMO

BACKGROUND: Secondary vaginal stenosis may occur after reconstruction of genital malformations in childhood or after failed vaginal aplasia repair in adults. AIM: This study focusses on the results of the surgical treatment of these patients in our multidisciplinary transitional disorders/differences of sex development team of pediatric surgeons and gynecologists. METHODS: A retrospective analysis was carried out on adult and female identified disorders/differences of sex development patients with vaginal stenoses treated between 2015 and 2018 in a single center with revision vaginoplasty. The underlying type of malformation, the number and surgical techniques of vaginoplasties in infancy, techniques of revision of the stenotic vagina, vaginal length and caliber, possibility of sexual intercourse, and temporary vaginal dilatation. A review of literature with regard to recommended surgical techniques of revision vaginoplasties was accomplished. OUTCOMES: To describe the surgical technique, the main outcome measures of this study are vaginal calipers after revision vaginoplasty as well as ability for sexual intercourse. RESULTS: Thirteen patients presented with vaginal stenosis with a median age of 19 years (range 16-31). All patients had one or more different types of vaginoplasties in their medical history, with a median age at first vaginoplasty of 15 months (0-233). Underlying anatomical conditions were urogenital sinus (n = 8), vaginal agenesis (n = 2), persistent cloacae (n = 2), and cloacal exstrophy (n = 1). The main symptoms were disability of sexual intercourse in 13 patients due to stenotic vaginal tissue. The most frequently performed surgical technique was partial urogenital mobilization with a perineal or lateral flaps (n = 10), followed by bowel vaginoplasty (n = 2), in 1 patient a revision vaginoplasty failed due to special anatomical conditions. In a median follow-up of 11 months, all but one patient presented with physiological vaginal length and width, and normal sexual intercourse in those with a partnership. CLINICAL IMPLICATIONS: Perineal flap with partial urogenital mobilization should be considered as a treatment of choice in severe cases of distal vaginal stenosis and after multiple failed former vaginoplasties, while bowel vaginoplasty should be reserved only for cases of complete cicatrization or high located stenosis of the vagina. STRENGTHS & LIMITATIONS: The strength of this study is the detailed description of several cases while the retrospective character is a limitation. CONCLUSION: In patients after feminizing genital repair, perineal flap with partial urogenital mobilization provides a normal anatomical outcome and allows unproblematic sexual intercourse. Ellerkamp V, Rall KK, Schaefer J, et al. Surgical Therapy After Failed Feminizing Genitoplasty in Young Adults With Disorders of Sex Development: Retrospective Analysis and Review of the Literature. J Sex Med 2021;18:1797-1806.


Assuntos
Coito , Transtornos do Desenvolvimento Sexual , Adolescente , Adulto , Criança , Constrição Patológica , Transtornos do Desenvolvimento Sexual/cirurgia , Feminino , Procedimentos Cirúrgicos em Ginecologia , Humanos , Estudos Retrospectivos , Vagina/cirurgia , Adulto Jovem
15.
J Med Case Rep ; 15(1): 362, 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34253226

RESUMO

BACKGROUND: Disorders of sex development are anomalies in which the development of urogenital ridge is undifferentiated for the male and female child. Imaging plays a vital role in investigating the gross anatomy and associated anomalies. Ultrasonography, such as genitography and magnetic resonance, is the primary modality for demonstrating internal gonads and genitalia. Early multidisciplinary approach in the management of ambiguous genitalia including early surgical intervention is the predominant practice, with few current considerations on deferral of genital reconstruction until adolescent age. CASE PRESENTATION: We report the rare case of a 24-year-old adult female from a majority ethnic group of the Volta region, Ghana who was diagnosed and raised as male, now requiring surgical restoration to the female gender. The surgical team decided to assign external genitalia to correspond with the already intact internal organs, thus constructing the vulva. Consent was given by the client and her family members for management and surgical intervention. The surgery was scheduled and duly performed with a successful outcome. Understanding and consent was sought from the patient for the purpose of using her images for teaching, scientific publication, and demonstrations. CONCLUSION: The advantages of deferring surgical reconstruction with psychological counseling after early assessment need to be considered to prevent inappropriate gender assignment.


Assuntos
Transtornos do Desenvolvimento Sexual , Transtornos do Desenvolvimento Sexual/cirurgia , Família , Feminino , Genitália/diagnóstico por imagem , Genitália Masculina , Gana , Humanos , Masculino , Ultrassonografia , Adulto Jovem
16.
J Pediatr Urol ; 17(4): 583-584, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34284957

RESUMO

INTRODUCTION: Ovotesticular disorder of sex development (OTD) is a rare condition. There's a lack of literature addressing gonad-sparing surgery for OTD. OBJECTIVE: Report the laparoscopic partial gonadectomy technique - gonad-sparing surgery - in an 11-year-old child, 46, XX karyotype with OTD with atypical genitalia. MATERIAL AND METHODS: After a complete diagnostic evaluation the patient underwent feminizing genitoplasty followed by laparoscopic partial gonadectomy (gonad-sparing surgery). The patient was positioned on supine position and Trendelenburg. One 5 mm port was placed on the umbilicus and two 3 mm ports in both flanks. A gonadal wedge biopsy was performed to achieve histopathological confirmation before resection. The testicular component of the ovotestis is clearly identified based on macroscopic aspects, and resected with laparoscopic scissors and limited use of electrocautery. DISCUSSION: This case was classified as bipolar or terminal ovotestis. At the 5-month follow-up, the patient attained menarche. No adverse outcomes have been recorded. Postoperative third year follow-up hormone evaluation revealed a= female pattern characteristic and ultrasound demonstraed uterine volume increase, as well as bilateral ovarian tissue development with follicles. CONCLUSIONS: Gonad-sparing procedure is feasible and desirable whenever possible, especially in 46, XX patients with female sex of rearing, since it preserves the fertility potential. The risk of malignancy must be monitored.


Assuntos
Transtornos do Desenvolvimento Sexual , Laparoscopia , Transtornos Ovotesticulares do Desenvolvimento Sexual , Criança , Feminino , Gônadas , Humanos , Transtornos Ovotesticulares do Desenvolvimento Sexual/diagnóstico , Transtornos Ovotesticulares do Desenvolvimento Sexual/cirurgia , Desenvolvimento Sexual
17.
Sci Rep ; 11(1): 13766, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215813

RESUMO

Sexual dimorphism in gene regulation, including DNA methylation, is the main driver of sexual dimorphism in phenotypes. However, the questions of how and when sex shapes DNA methylation remain unresolved. Recently, using mice with different combinations of genetic and phenotypic sex, we identified sex-associated differentially methylated regions (sDMRs) that depended on the sex phenotype. Focusing on a panel of validated sex-phenotype dependent male- and female-biased sDMRs, we tested the developmental dynamics of sex bias in liver methylation and the impacts of mutations in the androgen receptor, estrogen receptor alpha, or the transcriptional repressor Bcl6 gene. True hermaphrodites that carry both unilateral ovaries and contralateral testes were also tested. Our data show that sex bias in methylation either coincides with or follows sex bias in the expression of sDMR-proximal genes, suggesting that sex bias in gene expression may be required for demethylation at certain sDMRs. Global ablation of AR, ESR1, or a liver-specific loss of BCL6, all alter sDMR methylation, whereas presence of both an ovary and a testis delays the establishment of male-type methylation levels in hermaphrodites. Moreover, the Bcl6-LKO shows dissociation between expression and methylation, suggesting a distinct role of BCL6 in demethylation of intragenic sDMRs.


Assuntos
Metilação de DNA/genética , Receptor alfa de Estrogênio/genética , Proteínas Proto-Oncogênicas c-bcl-6/genética , Receptores Androgênicos/genética , Animais , Transtornos do Desenvolvimento Sexual/genética , Epigênese Genética , Feminino , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Fígado/crescimento & desenvolvimento , Fígado/metabolismo , Masculino , Camundongos , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Caracteres Sexuais , Sexismo , Testículo/crescimento & desenvolvimento , Testículo/metabolismo
18.
Mar Pollut Bull ; 170: 112633, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34171630

RESUMO

Organotin (OT) based Antifouling Systems (AFS) were globally banned by the AFS Convention since 2008, but the Republic of Cabo Verde did not ratify this Convention, nor did it develop a national legislation to control OT-AFS. Gemophos viverratus imposex and butyltin tissue contamination were assessed around the São Vicente Island (Cabo Verde) in 2019 and compared with the data available from 2012. The vas deferens sequence index (VDSI), the relative penis length (RPL), the percentage of females with imposex (%I) and the percentage of sterilized females (%S) in 2019 ranged from 0 to 4.0, 0-84.4%, 0-100% and 0-5.1%, respectively, whilst TBT reached maximum values of ≈30 ng TBT-Sn g-1 dw in the whelk tissues. These values are very similar to those registered in 2012, which indicates that TBT pollution has not decreased over the years, in contrast to the declining trend observed worldwide.


Assuntos
Transtornos do Desenvolvimento Sexual , Gastrópodes , Compostos Orgânicos de Estanho , Compostos de Trialquitina , Poluentes Químicos da Água , Animais , Cabo Verde , Transtornos do Desenvolvimento Sexual/induzido quimicamente , Monitoramento Ambiental , Feminino , Masculino , Compostos Orgânicos de Estanho/toxicidade , Compostos de Trialquitina/toxicidade , Poluentes Químicos da Água/análise
20.
BMC Ecol Evol ; 21(1): 133, 2021 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-34174830

RESUMO

BACKGROUND: Expression of sexual dimorphism is recognised in various fossil groups of molluscs such as the Ammonoidea, an extinct group of shelled cephalopods. During the Mesozoic, the best-documented sexual dimorphic examples are seen in the Jurassic superfamily Perisphinctoidea. It is usually expressed by distinct adult size and apertural modifications between the antidimorphs. Putative males (otherwise referred to as microconch) are small in size and develop lappets at the end of the shell while the females (macroconch) are larger and bear a simple peristome. Dubious cases are, however, known in that superfamily, which often relate to taxonomic biases or lack of diagnostic characters, and some others expose ontogenetic anomalies illustrated by 'sex reversals' in the shell morphology and ornamentation. RESULTS: The discovery of two specimens of the Callovian Aspidoceratidae Peltoceras athleta (Phillips), having both female and male features, questions the significance and causes of 'sex reversals' in the Ammonoidea. The two specimens have started with the macroconch ontogeny of Peltoceras athleta and show an apparent change toward maleness in the adult, as illustrated by their rounded whorl section, ribs retroversion, fading of the tubercles and lappets typical of the microconchs. Few other cases of female-to-male, as well as male-to-female 'sex reversal', are known in the fossil record, all belonging to the Jurassic Perisphinctoidea (families Perisphinctidae or Aspidoceratidae). Since all Jurassic Perisphinctoidea are strictly gonochoristic, these 'sex reversals' are pathological in nature and are herein referred to as a new forma-type pathology: namely "forma hermaphrodita". CONCLUSIONS: In the absence of any clear evidence of injury or parasitism, we hypothesize that such "forma hermaphrodita" individuals illustrate pathologic cases of intersexuality. Little is known about the ammonoid soft parts, and it is not possible to determine which internal sexual organs occur in specimens having both male and female external shell features. Abnormal feminisation and/or masculinisation also occur in modern cephalopods, the latter also grouping only gonochoric species. This phenomenon is similarly illustrated by a change in the adult body size and a mixing of both female and male structures. In that case, intersexuality is either advantageous in the population or caused sterility. The causes of intersexuality are not clearly established but environmental pollutants are evoked in modern cephalopods because they act as endocrine disrupters. 'Sex reversals' and/or non-functional reproductive abnormalities have also been caused by endocrine disrupters in various gonochoric gastropods species, but infestation, genetic abnormalities, temperature fluctuations or viruses are multiple causes, which can stimulate or inhibit neural-endocrinal activity by direct gonadal influence, and ultimately lead to feminisation or masculinisation in fishes, isopods, crustaceans, and gastropods as well. Regardless of whether "forma hermaphrodita" is due to an exogenic or endogenic cause, the record of intersex Perisphinctoidea in the Jurassic can be explained by the ready recognition of dimorphic pairs, and the easy collection of large and sufficiently preserved fossil palaeopopulations in which intersex specimens have statistically more chance to be found.


Assuntos
Cefalópodes , Transtornos do Desenvolvimento Sexual , Animais , Crustáceos , Feminino , Fósseis , Humanos , Masculino , Moluscos
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