Gonadal Tissue Research Articles

Clinical, genetic, and pathological analysis in 165 children with disorders of sex development

To investigate the clinical phenotypes, genetic characteristics, and pathological features of children with disorders of sex development (DSD). A retrospective analysis was conducted on epidemiological, clinical phenotype, chromosomal karyotype, gonadal pathology, and genotype data of 165 hospitalized children with DSD at Children's Hospital of Hebei Province and Tangshan Maternal and Child Health Hospital from August 2008 to December 2022. Among the 165 children with DSD, common presenting symptoms were short stature (62/165, 37.6%), clitoromegaly (33/165, 20.0%), cryptorchidism (28/165, 17.0%), hypospadias (24/165, 14.5%), and skin pigmentation abnormalities/exteriorized pigmented labia majora (19/165, 11.5%). Chromosomal karyotype analysis was performed on 127 cases, revealing 36 cases (28.3%) of 46,XX DSD, 34 cases (26.8%) of 46,XY DSD, and 57 cases (44.9%) of sex chromosome abnormalities. Among the sex chromosome abnormal karyotypes, the 45,X karyotype (11/57, 19%) and 45,X/other karyotype mosaicism (36/57, 63%) were more common. Sixteen children underwent histopathological biopsy of gonadal tissues, resulting in retrieval of 25 gonadal tissues. The gonadal tissue biopsies revealed 3 cases of testes, 3 cases of dysplastic testes, 6 cases of ovaries, 11 cases of ovotestes, and 1 case each of streak gonad and agenesis of gonads. Genetic testing identified pathogenic/likely pathogenic variants in 23 cases (23/36, 64%), including 12 cases of 21-hydroxylase deficiency congenital adrenal hyperplasia caused by CYP21A2 pathogenic variants. Short stature, clitoromegaly, cryptorchidism, hypospadias, and skin pigmentation abnormalities are common phenotypes in children with DSD. 45,X/other karyotype mosaicism and CYP21A2 compound heterozygous variants are major etiological factors in children with DSD. The most commonly observed gonadal histopathology in children with DSD includes ovotestes, ovaries, and testes/dysgenetic testes.

Possible germline progenitor cells in extra-gonadal tissues of the sea anemone, Exaiptasia diaphana

Many anthozoans, e.g., sea anemones and corals, have remarkable capacities for asexual reproduction and regeneration, creating complete individual polyps from pieces of parental polyp tissue. Notably, polyps produced asexually (or regenerated) from somatic tissues that originally contain no gonads are capable of sexual reproduction. However, how somatically derived polyps can reproduce remains largely unexplored. Here, using a sea anemone, Exaiptasia diaphana, we show that potential germline progenitor cells are present in the extra-gonadal tissues, and that they are allocated to newly produced individuals during asexual reproduction/regeneration. Histological analysis of E. diaphana demonstrated that polyps asexually produced from pedal lacerates can create mature gametes. Amputation experiments showed that polyps regenerated from the head, which originally lacked gonadal tissue, formed gonads and initiated gametogenesis. Immunohistochemical analysis with a germline marker, vasa, demonstrated the presence of vasa-positive cells in various polyp tissues. These findings suggest that vasa-positive cells in extra-gonadal tissues may be a reservoir of germline progenitor cells to ensure sexual reproductive capacity in individuals produced asexually or regenerated from somatic tissues.

The lymphatic system favours survival of a unique T. brucei population.

Trypanosoma brucei colonize and multiply in the blood vasculature, as well as in various organs of the host's body. Lymph nodes have been previously shown to harbour large numbers of parasites, and the lymphatic system has been proposed as a key site that allows T. brucei distribution through, and colonization of the mammalian body. However, visualization of host-pathogen interactions in the lymphatic system has never captured dynamic events with high spatial and temporal resolution throughout infection. In our work, we used a mixture of tools including intravital microscopy and ex vivo imaging to study T. brucei distribution in 20 sets of lymph nodes. We demonstrate that lymph node colonization by T. brucei is different across lymph node sets, with the most heavily colonized being the draining lymph nodes of main tissue reservoirs: the gonadal white adipose tissue and pancreas. Moreover, we show that the lymphatic vasculature is a pivotal site for parasite dispersal, and altering this colonization by blocking LYVE-1 is detrimental for parasite survival. Additionally, parasites within the lymphatic vasculature have unique morphological and behavioural characteristics, different to those found in the blood, demonstrating that across both types of vasculature, these environments are physically separated. Finally, we demonstrate that the lymph nodes and the lymphatic vasculature undergo significant alterations during T. brucei infection, resulting in oedema throughout the host's body.

Metabolic scaling variation as a constitutive adaptation to tide level in Mytilus galloprovincialis

Understanding how allometric exponents vary in the different biologically determined patterns turns out to be fundamental for the development of a unifying hypothesis that intends to explain most of the variation among taxa and physiological states. The aims of this study were (i) to analyze the scaling exponents of oxygen consumption at different metabolic rates in Mytilus galloprovincialis according to different seasons, habitat, and acclimation to laboratory conditions and (ii) to examine the variation in shell morphology depending on habitat or seasonal environmental hazards. The allometric exponent for standard metabolic rate (b value) did not vary across seasons or tide level, presenting a consistent value of 0.644. However, the mass-specific standard oxygen consumption (a value), i.e. metabolic level, was lower in intertidal mussels (subtidal mussels: a = - 1.364; intertidal mussels: a = - 1.634). The allometric exponent for routine metabolic rate changed significantly with tide level: lower allometric exponents for intertidal mussels (b = 0.673) than for subtidal mussels (b = 0.871). This differential response did not change for at least two months after the environmental cue was removed. We suggest that this is the result of intertidal mussels investing fundamentally in surface-dependent organs (gill and shell), with the exception of the slightly higher values obtained in May as a likely consequence of gonadal tissue development. Subtidal mussels, on the contrary, are probably in constant demand for volume-related resources, which makes them consistently obtain an allometric exponent of around 0.87.

A Case of Ovarian Hyperthecosis in a Postmenopausal Woman

Abstract We report a case of a 55-year-old postmenopausal woman who presented with symptoms of fatigue, male pattern hair loss, and hirsutism over 3 years. Investigations showed elevated total testosterone levels of 5.0 nmol/L (1.44 ng/mL; range, 0.3-3.1 nmol/L) using Beckman-Unicel-DXI-800 immunoassay. Testosterone levels were repeated by liquid chromatography-tandem mass spectrometry and were found to be elevated at 7.3 nmol/L (2.10 ng/mL). Estradiol was detectable and free androgen index was elevated. Dehydroepiandrosterone sulfate levels and androstenedione were within normal range, suggesting a nonadrenal source. Computed tomography scan of the abdomen showed no evidence of adrenal or adnexal tumor. GnRH analog stimulation test led to reduction of gonadotrophins and normalization of testosterone within 4 weeks. She had a biopsy of a cranial hair follicle, which showed androgenic alopecia. These investigations confirmed an ovarian source of androgens. Subsequently, she underwent bilateral salpingo-oophorectomy. Histological study of gonadal tissue confirmed the diagnosis of ovarian hyperthecosis. Four weeks after oophorectomy, her testosterone levels normalized and clinical symptoms improved. Ovarian hyperthecosis is a rare cause of hyperandrogenism in postmenopausal women and can pose a diagnostic and therapeutic challenge. Careful history and physical examination along with critical analysis of biochemistry and imaging studies is crucial for correct diagnosis.

Pseudohermafroditismo masculino en una perra: Reporte de caso

Pseudohermaphroditism is an anomaly in the development of the reproductive system, and scarcely reported in Veterinary Medicine. Its etiology is not well elucidated, but studies show that it can be congenital or hereditary. Animals that have this condition have distinct phenotypic characteristics of their gonadal tissue. The study reports a bitch with no defined breed, nine months old and without a history of estrus, who presents external female genitalia and a penis in the vaginal canal. The patient was referred for ultrasound examination, which found the presence of testicles in subcutaneous and intrabdominal topography, without evidence of a uterus or ovaries. The patient was referred for exploratory laparotomy, orchiectomy and penectomy. Based on the phenotypic, sonographic and histological characteristics, it is concluded that this is a dog with male pseudohermaphroditism.

DNA Methylation Profiling of Ovarian Tissue of Climbing Perch (Anabas testudienus) in Response to Monocrotophos Exposure.

Epigenetic modifications like DNA methylation can alter an organism's phenotype without changing its DNA sequence. Exposure to environmental toxicants has the potential to change the resilience of aquatic species. However, little information is available on the dynamics of DNA methylation in fish gonadal tissues in response to organophosphates. In the present work, reduced-representation bisulfite sequencing was performed to identify DNA methylation patterns in the ovarian tissues of Anabas testudienus exposed to organophosphates, specifically monocrotophos (MCP). Through sequencing, an average of 41,087 methylated cytosine sites were identified and distributed in different parts of genes, i.e., in transcription start sites (TSS), promoters, exons, etc. A total of 1058 and 1329 differentially methylated regions (DMRs) were detected as hyper-methylated and hypo-methylated in ovarian tissues, respectively. Utilizing whole-genome data of the climbing perch, the DMRs, and their associated overlapping genes revealed a total of 22 genes within exons, 45 genes at transcription start sites (TSS), and 218 genes in intergenic regions. Through gene ontology analysis, a total of 16 GO terms particularly involved in ovarian follicular development, response to oxidative stress, oocyte maturation, and multicellular organismal response to stress associated with reproductive biology were identified. After functional enrichment analysis, relevant DMGs such as steroid hormone biosynthesis (Cyp19a, 11-beta-HSD, 17-beta-HSD), hormone receptors (ar, esrrga), steroid metabolism (StAR), progesterone-mediated oocyte maturation (igf1ar, pgr), associated with ovarian development in climbing perch showed significant differential methylation patterns. The differentially methylated genes (DMGs) were subjected to analysis using real-time PCR, which demonstrated altered gene expression levels. This study revealed a molecular-level alteration in genes associated with ovarian development in response to chemical exposure. This work provides evidence for understanding the relationship between DNA methylation and gene regulation in response to chemicals that affect the reproductive fitness of aquatic animals.

Exploring the molecular and toxicological mechanism associated with interactions between heavy metals and the reproductive system of Mytilus galloprovincialis

A large number of heavy metals resulted toxic to the reproductive system, but invertebrate infertility has been poorly explored, and above all, there are limited molecular, cellular and toxicological studies. In the present work, we exposed Mytilus galloprovincialis to three individual metal chlorides (CuCl2 15 μM, CdCl2 1.5 μM, NiCl2 15 μM) and their mixture for 24 h, to evaluate the effects on the protamine-like proteins (PLs), sperm DNA and on their interaction in the formation of sperm chromatin. Under all exposure conditions, but particularly after exposure to the metals mix, relevant changes in the electrophoretic pattern, by AU-PAGE and SDS-PAGE, and in fluorescence spectroscopy measurements of PLs were shown. In addition, alterations in DNA binding of these proteins were observed by Electrophoretic Mobility Shift Assay (EMSA) and through their release from sperm nuclei. Moreover, there was evidence of increased accessibility of micrococcal nuclease to sperm chromatin, which was also confirmed by toluidine blue staining. Furthermore, morphological analyses indicated severe gonadal impairments which was also corroborated by increased PARP expression, by Western blotting, and sperm DNA fragmentation, by comet assay. Finally, we investigated the expression of stress genes, gst, hsp70 and mt10, in gonadal tissue. The latter investigations also showed that exposure to this metals mix was more harmful than exposure to the individual metals tested. The present results suggest that these metals and in particular their mixture could have a negative impact on the reproductive fitness of M. galloprovincialis. Based on these evidences, we propose a molecular mechanism.

Adipocyte lipolysis protects mice against Trypanosoma brucei infection

Trypanosoma brucei causes African trypanosomiasis, colonizing adipose tissue and inducing weight loss. Here we investigated the molecular mechanisms responsible for adipose mass loss and its impact on disease pathology. We found that lipolysis is activated early in infection. Mice lacking B and T lymphocytes fail to upregulate adipocyte lipolysis, resulting in higher fat mass retention. Genetic ablation of the rate-limiting adipose triglyceride lipase specifically from adipocytes (AdipoqCre/+-Atglfl/fl) prevented the stimulation of adipocyte lipolysis during infection, reducing fat mass loss. Surprisingly, these mice succumbed earlier and presented a higher parasite burden in the gonadal adipose tissue, indicating that host lipolysis limits parasite growth. Consistently, free fatty acids comparable with those of adipose interstitial fluid induced loss of parasite viability. Adipocyte lipolysis emerges as a mechanism controlling local parasite burden and affecting the loss of fat mass in African trypanosomiasis.

FIGO statement: Fertility preservation.

Fertility preservation is a growing field in reproductive medicine that may raise ethical questions. Preservation of fertility must be discussed with the patient if gonadotoxic treatment is required, whether in the case of benign or malignant pathology, or in the management of transgender identity. As a result, surgery or chemotherapy that has fewer adverse impacts on fertility should be proposed if this does not alter the prognosis of the disease. If the risk of infertility persists, then fertility cryopreservation should be proposed for children and adults of reproductive age. Sperm, oocytes, and gonadal tissue can be cryopreserved for many years. FIGO wishes to emphasize the importance of fertility preservation in the medical and surgical management of patients, and the importance of a specialized, multidisciplinary approach.

SAT343 Nicotinamide Nucleotide Transhydrogenase (NNT)-related Familial Glucocorticoid Deficiency: More Than Adrenal Insufficiency

Abstract Disclosure: A. Shanker: None. H.L. Calero: None. K. DeCarlo: None. Background: Familial glucocorticoid deficiency (FGD) is a rare cause of primary adrenal insufficiency, with an estimated prevalence of fewer than 5,000 cases in the United States. Patients often present as infants with signs including hypoglycemia, failure to thrive, seizures, and recurrent infections. Clinical Case: A 25-year-old woman with a history of intellectual disability was admitted with MIS-A due to COVID-19. Her presenting symptoms were lethargy and fever for several days. Her vitals were significant for a heart rate of 122 with atrial flutter and blood pressure of 90/50. Her initial labs showed elevated TSH (24.07 mcIU/mL [0.35-4.00]), normal free T4 (0.7 ng/dL [0.6-1.7]), hyponatremia (133 mmol/L [135-145]), and low alkaline phosphatase (25 U/L [40-125). Her physical exam was notable for hyperpigmentation, macrognathia, and oral mucositis. Her parents report she has limited daily activities and recalls recurrent illnesses as a child. She has been amenorrheic for the past 5 years; menarche was at age 12. Further chart review revealed that ketotic hypoglycemic seizure was diagnosed during hospitalization at 11 months of age. . Pediatric Endocrinology diagnosed Addison’s disease, which was treated until age 12 when she was lost to follow-up. On this admission, ACTH was elevated (756.5 pg/mL [7.2 - 63.3]), 8 AM cortisol was 1.2 ug/dL, and peak cortisol obtained after high dose co-syntropin stimulation was abnormal at 1.1 ug/dL upon high dose. Primary adrenal insufficiency was confirmed, and stress-dose steroids were initiated; her clinical condition improved. She was discharged with prednisone and fludrocortisone maintenance therapy. As an outpatient, TSH was persistently elevated (17.9 mcIU/mL [0.35-4.00]) and weight-based levothyroxine was initiated. Secondary amenorrhea testing demonstrated normal FSH, LH, and estradiol levels and discussions began regarding progesterone withdrawal testing (pending given patient again lost to follow up). The nutritional screening revealed deficiencies in vitamins A, C, and D, and supplementation was initiated. A unifying diagnosis was reached with microarray and whole exome sequencing showing nicotinamide nucleotide transhydrogenase (NNT) -related FGD. Conclusions: In FGD, several causative genes have been identified. One of these, NNT is expressed in most tissues, including cardiac, renal, thyroid, gastrointestinal, and gonadal tissue. This may predispose patients to organ dysfunction outside of the prominent effect on the adrenal glands. Since NNT is widely expressed, routine screening can include nutritional, renal, and hepatic labs and patients should receive reproductive counseling due to the risk of gonadal dysfunction. Therefore, patients with NNT-related glucocorticoid FGD require significant care coordination to ensure that patients receive uninterrupted therapy and appropriate multispecialty follow-up. Presentation: Saturday, June 17, 2023

Monthly Variation of Tetrodotoxin Levels in Pufferfish (Lagocephalus sceleratus) Caught from Antalya Bay, Mediterranean Sea.

The silver-cheeked toadfish (Lagocephalus sceleratus), an invasive alien pufferfish species that has rapidly settled throughout the Mediterranean region, poses significant threats not only to native marine species and fisheries but also to public health due to the tetrodotoxin (TTX) they harbor. In this study, TTX concentrations in L. sceleratus from Antalya Bay in the Northeastern Mediterranean Sea were investigated using Q-TOF-LC-MS on a monthly basis over a one-year period. Pufferfish were caught by angling from May 2018 to April 2019. The TTX levels in three different tissues (gonads, liver, and muscle) of 110 pufferfish in total were determined in both male and female individuals caught for 11 months. The highest TTX mean levels generally occurred in the gonads and the lowest in the muscle samples. As regards the maximum TTX contents, the highest concentrations determined were 68.2, 34.2, and 7.8 µg/g in the gonad, liver, and muscle tissues, respectively. The highest levels were generally observed in late autumn to winter (especially in November and December) in all tissues from both genders. Female individuals were generally found to be more toxic than male individuals. The TTX levels found confirm that the consumption of L. sceleratus from Antalya Bay remains dangerous throughout the year, and thus L. sceleratus constantly constitutes an important risk source for public health.

Seasonal changes in the reproductive cycle and condition index of the surf clam Mactra stultorum (Mollusca: Bivalvia) in the Gulf of Gabes, Tunisia

The reproductive biology of Mactra stultorum from the Gulf of Gabes was investigated monthly during a oneyear period (2017). This study is the first study examining its reproductive biology during one-year in the south of Tunisia. The overall samples presented a balanced sex ratio, with males dominating among smaller individuals (< 22 mm) and females predominating in larger size classes (> 34 mm). The obtained total sex ratio (F:M) was equal to 1.03:1. The size at first maturity (SL50%) was 20.43 and 22.10 mm for males and females, respectively. The seasonal variations assessed through macro- and microscopic characteristics in the gonads of both sexes indicated a clearly defined annual reproductive cycle with a principal spawning peak during summer and a resting period during December and January. The reproduction of M. stultorum was strongly influenced by fluctuations in the seawater temperature, as reflected through the temporal variation in the gonadal cycle, condition index (CI) and tissue weight rate (TiWR). If managed properly, M. stultorum is expected to meet the domestic market demand through artisanal fishery. The adoption and implementation of rules, such as limiting the size of clams, is required to protect this new exploitable fishery resource.

Microsporidia MB in the primary malaria vector Anopheles gambiae sensu stricto is avirulent and undergoes maternal and horizontal transmission

BackgroundThe demonstration that the recently discovered Anopheles symbiont Microsporidia MB blocks malaria transmission in Anophelesarabiensis and undergoes vertical and horizontal transmission suggests that it is a promising candidate for the development of a symbiont-based malaria transmission-blocking strategy. The infection prevalence and characteristics of Microsporidia MB in Anopheles gambiae sensu stricto (s.s.), another primary vector species of malaria in Kenya, were investigated.MethodsField-collected females were confirmed to be Microsporidia MB-positive after oviposition. Egg counts of Microsporidia MB-infected and non-infected individuals were used to infer the effects of Microsporidia MB on fecundity. The time to pupation, adult sex ratio and survival were used to determine if Microsporidia MB infection has similar characteristics in the host mosquitoes An. gambiae and An. arabiensis. The intensity of Microsporidia MB infection in tissues of the midgut and gonads, and in carcasses, was determined by quantitative polymerase chain reaction. To investigate horizontal transmission, virgin males and females that were either Microsporidia MB-infected or non-infected were placed in standard cages for 48 h and allowed to mate; transmission was confirmed by quantitative polymerase chain reaction targeting Microsporidia MB genes.ResultsMicrosporidia MB was found to naturally occur at a low prevalence in An. gambiae s.s. collected in western Kenya. Microsporidia MB shortened the development time from larva to pupa, but other fitness parameters such as fecundity, sex ratio, and adult survival did not differ between Microsporidia MB-infected and non-infected hosts. Microsporidia MB intensities were high in the male gonadal tissues. Transmission experiments indicated that Microsporidia MB undergoes both maternal and horizontal transmission in An. gambiae s.s.ConclusionsThe findings that Microsporidia MB naturally infects, undergoes maternal and horizontal transmission, and is avirulent in An. gambiae s.s. indicate that many of the characteristics of its infection in An. arabiensis hold true for the former. The results of the present study indicate that Microsporidia MB could be developed as a tool for the transmission-blocking of malaria across different Anopheles species.Graphical

Non-gonadal somatic piRNA pathways ensure sexual differentiation, larval growth, and wing development in silkworms.

PIWI-interacting RNAs (piRNAs) guide PIWI proteins to target transposons in germline cells, thereby suppressing transposon activity to preserve genome integrity in metazoans' gonadal tissues. Piwi, one of three Drosophila PIWI proteins, is expressed in the nucleus and suppresses transposon activity by forming heterochromatin in an RNA cleavage-independent manner. Recently, Piwi was reported to control cell metabolism in Drosophila fat body, providing an example of piRNAs acting in non-gonadal somatic tissues. However, mutant flies of the other two PIWI proteins, Aubergine (Aub) and Argonaute3 (Ago3), show no apparent phenotype except for infertility, blurring the importance of the piRNA pathway in non-gonadal somatic tissues. The silkworm, Bombyx mori, possesses two PIWI proteins, Siwi (Aub homolog) and BmAgo3 (Ago3 homolog), whereas B. mori does not have a Piwi homolog. Siwi and BmAgo3 are mainly expressed in gonadal tissues and play a role in repressing transposon activity by cleaving transposon RNA in the cytoplasm. Here, we generated Siwi and BmAgo3 loss-of-function mutants of B. mori and found that they both showed delayed larval growth and failed to become adult moths. They also exhibited defects in wing development and sexual differentiation. Transcriptome analysis revealed that loss of somatic piRNA biogenesis pathways results in abnormal expression of not only transposons but also host genes, presumably causing severe growth defects. Our results highlight the roles of non-gonadal somatic piRNAs in B. mori development.

Comparative transcriptome analysis reveals key genes and pathways related to gonad development in the sea cucumber Apostichopus japonicus

The sea cucumber Apostichopus japonicus is an economically important marine species in China, and understanding the mechanisms underlying its gonad development is crucial for successful reproduction and breeding. In this study, we performed transcriptome comparisons and analyses of A. japonicus gonadal and non-gonadal tissues to identify genes and molecular pathways associated with gonadal development. We also supplemented the annotation of the A. japonicus genome. Collectively, results revealed a total of 941 ovary-specific genes and 2499 testis-specific genes through different expression analysis and WGCNA analysis. The most enriched pathways in ovary and testis were “DNA replication” and “purine metabolism”, respectively. Additionally, we identified key candidate gene modules that control gonad development and germ cell maturation, with CDT1 and DYNC2LI1 serving as hub genes. Our findings provide important insights into the gonadal development system of A. japonicus and offer valuable references for further research on reproductive biology in this marine invertebrate species.

Gonadotropin Receptor Cross-Talk and Altered Functions in Gonadal and Non-Gonadal Tissues

Reproduction depends on the responses of gonadotropins through their specific receptors. The gonadotropin family has three members; Follicle Stimulating Hormone (FSH), Luteinizing Hormone (LH), and Human Chorionic Gonadotropin (hCG). These glycoprotein hormones comprise two subunits, an identical α-subunit and a hormone-specific-β subunit. Their cognate receptors (FSHR and LHCGR) are two adrenergic receptor-like family A/rhodopsin-like G-Protein Coupled Receptors (GPCRs) with structurally distinct ligand binding domains. The hCG binds to LHCGR but has a longer half-life and higher affinity to LHCGR. The expression of FSHR and LHCGR is observed in both gonadal and nongonadal cells. In this review, we will be emphasizing the differential expression of gonadotropin receptors in different cells of the human body, their specific responses through cross-talk, and how a defect in the expression and activity of FSHR and LHCGR may alter the responses of FSH and LH/hCG leading to diseases like PCOS, cancer and metabolic disorders.

Etiology, histology, and long-term outcome of bilateral testicular regression: a large Belgian series

Abstract STUDY QUESTION What is the long-term outcome of individuals born with bilateral testicular regression (BTR) in relation to its underlying etiology? SUMMARY ANSWER Statural growth and pubertal development are adequate with incremental doses of testosterone replacement therapy (TRT); however, penile growth is often suboptimal, especially in those with a suspected genetic etiology (i.e. heterozygous DHX37 variants) or a micropenis at birth. WHAT IS KNOWN ALREADY BTR is a rare and poorly understood condition. Although a vascular origin has been postulated, heterozygous missense variants in DHX37 have been attributed to the phenotype as well. How these various etiologies impact the clinical phenotype, gonadal histology and outcome of BTR remains unclear. STUDY DESIGN, SIZE, DURATION For this cross-sectional study, individuals with BTR were recruited in eight Belgian pediatric endocrinology departments, between December 2019 and December 2022. A physical exam was performed cross-sectionally in all 17 end-pubertal participants and a quality of care questionnaire was completed by 11 of them. Exome-based panel testing of 241 genes involved in gonadal development and spermatogenesis was performed along with a retrospective analysis of presentation and management. A centralized histological review of gonadal rests was done for 10 participants. PARTICIPANTS/MATERIALS, SETTING, METHODS A total of 35 participants (33 with male, 1 with female, and 1 with non-binary gender identity) were recruited at a mean age of 15.0 ± 5.7 years. MAIN RESULTS AND THE ROLE OF CHANCE The median age at presentation was 1.2 years [0–14 years]. Maternal gestational complications were common (38.2%), with a notably high incidence of monozygotic twin pregnancies (8.8%). Heterozygous (likely) pathogenic missense variants in DHX37 (p.Arg334Trp and p.Arg308Gln) were found in three participants. No other (likely) pathogenic variants were found. All three participants with a DHX37 variant had a microphallus at birth (leading to female sex assignment in one), while only six of the remaining 31 participants without a DHX37 variant (19.4%) had a microphallus at birth (information regarding one participant was missing). Testosterone therapy during infancy to increase penile growth was more effective in those without versus those with a DHX37 variant. The three participants with a DHX37 variant developed a male, female, and non-binary gender identity, respectively; all other participants identified as males. TRT in incremental doses had been initiated in 25 participants (median age at start was 12.4 years). Final height was within the target height range in all end-pubertal participants; however, 5 out of 11 participants (45.5%), for whom stretched penile length (SPL) was measured, had a micropenis (mean adult SPL: 9.6 ± 2.5). Of the 11 participants who completed the questionnaire, five (45.5%) reported suboptimal understanding of the goals and effects of TRT at the time of puberty induction. Furthermore, only 6 (54.5%) and 5 (45.5%) of these 11 participants indicated that they were well informed about the risks and potential side effects of TRT, respectively. Histological analysis of two participants with DHX37 variants suggested early disruption of gonadal development due to the presence of Müllerian remnants in both and undifferentiated gonadal tissue in one. In eight other analyzed participants, no gonadal remnants were found, in line with the BTR diagnosis. LIMITATIONS, REASONS FOR CAUTION The limitations of this study include the relatively small sample size (n = 35) and the few individuals with DHX37 variants (n = 3). Furthermore, data on the SPL were often missing, due to this being undocumented or refused by participants. WIDER IMPLICATIONS OF THE FINDINGS TRT provides adequate statural growth, even when initiated in late adolescence, thus providing time for physicians to explore the patients’ gender identity if needed. However, sufficient and understandable information regarding the effects and side effects of TRT is required throughout the management of these patients. SPL remains suboptimal in many individuals and could be improved by TRT during infancy to mimic the physiological mini-puberty. An environmental origin in some participants is supported by the high incidence of gestational complications (38.2%) and by the three monozygotic twin pregnancies discordant for the BTR phenotype. Individuals with a heterozygous DHX37 variant have a more severe phenotype with severely restricted penile growth until adulthood. Histological analysis confirmed DHX37 as a gonadal development, rather than a BTR-related, gene. STUDY FUNDING/COMPETING INTEREST(S) Funding was provided by the Belgian Society for Pediatric Endocrinology and Diabetology (BESPEED) and by Ghent University Hospital under the NucleUZ Grant (E.D.B.). M.C. and E.D.B. are supported by an FWO senior clinical investigator grant (1801018N and 1802220N, respectively). The authors report no conflicts of interest. TRIAL REGISTRATION NUMBER N/A.

Differential depot-specific parameters of adipose tissue cellularity and thermogenesis in preobese congenic LA/Ntul//-cp rats

To determine the effects of adipose tissue development during early normal postweaning growth, groups of lean and obese LA/N//tul-cp rats were subjected to measures of caloric intake, linear growth and of adipose tissue mass, cell lipid content, and adipocyte number in principle adipose tissue depots at 6 weeks of age, prior to the expression of significant adiposity. Live body weights and daily caloric intake of obese > lean by 6 weeks of age, but parameters of linear growth were similar in both phenotypes. Resting metabolic rate (RMR) and the thermic response to norepinephrine (NE, 200 µg/KG BW, s.c.) of lean >> obese rats. Adipose tissue mass and combined fat pad mass:body weight ratio of Dorsal Subcutaneous (DOR), Retroperitoneal (RP), Gonadal (GON), and Interscapular brown adipose tissue (IBAT) depots were greater in the obese than lean phenotype, with the greatest magnitude of increase in the DOR subcutaneous depot. Adipocyte number was modestly greater in DOR subcutaneous depot, while adipocyte lipid content was greater in the RP and GON depots of obese but not lean rats. The IBAT mass and proportion of IBAT:body weight of obese >> lean. These results are consistent with the differential onset of adipose tissue depot growth initially occurs via hyperplasia in the dorsal subcutaneous depot and via hypertrophy in the RP and GON abdominal depots, while lean tissue development was of similar magnitude in both phenotypes at this age.

Reproductive cycle of the yellow clam Amarilladesma mactroides (Reeve, 1854)

Studies on the reproductive cycle are essential for understanding the reproduction of a species. No studies on the reproductive cycle of Amarilladesma mactroides in Brazil have been conducted. Therefore, the present study sought to analyze, in the wild, the influence of the seasons on the development of the gonadic tissue of the yellow clam in southern Brazil (28°50’10.4”S, 49°13’55.7”W) and to evaluate the effect of water temperature on the development of gonadic tissue and its growth in the laboratory. A total of 227 animals were collected monthly between October 2019 and October 2020 to evaluate the reproductive cycle of the species using a condition index (CI) and histological analysis. In addition, the effect of temperature (17 °C and 23 °C) on the maturation and growth of 270 animals was evaluated in the laboratory. A higher CI was observed in autumn and winter when compared to that observed in spring and summer. The results of the histological analyses corroborated those obtained for the CI, demonstrating that the mature animals had a higher CI than the immature animals. Animals exposed to a temperature of 23 °C reached maturation faster than those exposed to a temperature of 17 °C. At both temperatures, the animals increased in shell length and total live weight, with no significant differences in these parameters between the temperatures. It was concluded that 23 °C is the most suitable temperature for the maturation of A. mactroides in the laboratory and that the best season of the year to collect wild animals for subsequent spawning induction in the laboratory is winter.