Characterization of CD8+ T cells in immune-privileged organs of ZIKV-infected Ifnar1-/- mice.

Zika virus (ZIKV) infection caused neurological complications and male infertility, leading to the accumulation of antigen-specific immune cells in immune-privileged organs (IPOs). Thus, it is important to understand the immunological responses to ZIKV in IPOs. We extensively investigated the ZIKV-specific T cell immunity in IPOs in Ifnar1-/- mice, based on an immunodominant epitope E294-302 tetramer. The distinct kinetics and functions of virus-specific CD8+ T cells infiltrated into different IPOs were characterized, with late elevation in the brain and spinal cord. Single epitope E294-302-specific T cells can account for 20-60% of the total CD8+ T cells in the brain, spinal cord, and testicle and persist for at least 90 days in the brain and spinal cord. The E294-302-specific TCRαßs within the IPOs are featured with the majority of clonotypes utilizing TRAV9N-3 paired with diverse TRBV chains, but with distinct αß paired clonotypes in 7 and 30 days post-infection. Specific chemokine receptors, Ccr2 and Ccr5, were selectively expressed in the E294-302-specific CD8+ T cells within the brain and testicle, indicating an IPO-oriented migration of virus-specific CD8+ T cells after infection. Overall, this study adds to the understanding of virus-specific CD8+ T cell responses for controlling and clearing ZIKV infection in IPOs.IMPORTANCEThe immune-privileged organs (IPOs), such as the central nervous system and testicles, presented pathogenicity and inflammation after Zika virus (ZIKV) infection with infiltrated CD8+ T cells. Our data show that CD8+ T cells keep up with virus increases and decreases in immune-privileged organs. Furthermore, our study provides the first ex vivo comparative analyses of the composition and diversity related to TCRα/ß clonotypes across anatomical sites and ZIKV infection phases. We show that the vast majority of TCRα/ß clonotypes in tissues utilize TRAV9N-3 with conservation. Specific chemokine expression, including Ccr2 and Ccr5, was found to be selectively expressed in the E294-302-specific CD8+ T cells within the brain and testicle, indicating an IPO-oriented migration of the virus-specific CD8+ T cells after the infection. Our study adds insights into the anti-viral immunological characterization and chemotaxis mechanism of virus-specific CD8+ T cells after ZIKV infection in different IPOs.

Reproductive endocrinology, morphological traits, and sexual selection in a population of wild South African giraffes.

Sex steroids are pervasive in mammals and evolutionarily conserved, but differences in the nuances of endocrine profiles characterize distinct species. Two sex steroids, testosterone and progesterone, feature prominently in the life history of mammalian taxa, but neither one has been analyzed from wild giraffes. Our study was designed to address this gap in knowledge by examining how these sex steroids are related to biological features and giraffe life history. We conducted the research at Rooipoort Nature Reserve a 44,000 ha private nature reserve in South Africa on a population of South African giraffes (Giraffa camelopardalis giraffa). Eleven adult giraffe cows and seven adult bulls were immobilized and various biological samples and morphological measurements were obtained. We analyzed both testosterone and progesterone using Ultra High Performance Liquid Chromotography - Tandem Mass Spectrometry (UHPLC-MS/MS). We found that non-pregnant females had lower progesterone concentrations than pregnant females and that those in the last trimester of pregnancy showed a slight drop in progesterone, as well as an increase in testosterone. Among males, chronological age was correlated with testicle size, testosterone concentrations, and ossicone volume. We propose that the progesterone decline functions partly to accelerate resumption of ovulation because giraffes become pregnant while lactating, and that the testosterone elevation provides an endocrine mileu for female defense of neonatal calves, given that lion predation is a major threat to calf survival. We suggest that male reproductive strategies are mediated by the age-related impacts of testosterone on growth in both body mass and ossicone volume as a consequence of sexual selection. We conclude by noting that the robust and solid ossicones of male giraffes function in mate competition as wedges that are used to topple opponents by raising their legs and placing them in an off-balanced position that can seriously injure them when falling to the ground.

National survey of physicians in Swedish child health centres finds insecurity and unawareness regarding management of undescended testicles.

AIM: To investigate underlying factors for previously reported shortcomings in child health centres' (CHC) referral process of boys with undescended testicles. METHODS: A total of 386 physicians working at Swedish CHCs were surveyed regarding their knowledge about undescended testicles and their clinical management. Multivariate regression analyses were performed to identify risk factors of non-adherence to guidelines and self-reported lack of clinical skills. RESULTS: The overall knowledge of the health benefits of undescended testicle surgery was high (89%), while two-thirds were unaware of surgery being recommended <1 year of age. One-fifth of respondents had never received guidance on examination techniques. Male gender (adjusted odds ratio [aOR] 0.51, 95% confidence interval [95% CI] 0.31-0.86), education in paediatrics (aOR 0.37, 95% CI 0.18-0.76) and more experience (aOR 0.02, 95% CI 0.01-0.09) significantly decreased the risk of unfamiliarity with examinations. More experience decreased the risk of stating the incorrect indications for undescended testicle surgery (aOR 0.17, 95% CI 0.03-0.95) and finding examinations difficult (aOR 0.22, 95% CI 0.07-0.72). Medical education outside Nordic countries was a risk factor for unawareness of guidelines (aOR 2.06, 95% CI 1.21-3.51). CONCLUSION: The knowledge and confidence level of the study population varied widely. The results indicate a need for further theoretical and practical education among Swedish CHC physicians.

Low energy availability reduces bone mass and gonadal function in male mice.

INTRODUCTION: In women, the female athlete triad, marked by low energy availability, functional hypothalamic amenorrhea and osteoporosis, is a recognized risk for stress fractures. Stress injuries also occur in men, but by contrast risks and mechanisms underlying them are less characterized. MATERIALS AND METHODS: 5 week-old wild-type male mice were fed ad libitum (ad) or subjected to 60% food restriction (FR) for five weeks. In both groups, some mice were allowed access to an exercise wheel in cages to allow voluntary wheel running (ex) and/or treated with active vitamin D analogues. Mice were sacrificed and analyzed at 10 weeks of age. RESULT: Male FR mice exhibited significantly reduced testicle weight, serum testosterone levels and bone mass. Such bone losses in FR male mice were enhanced by exercise. Histological analysis revealed that both bone-resorbing and -forming activities were significantly reduced in FR or FR plus exercise (FR + ex) mice, mimicking a state of low bone turnover. Significantly reduced bone mass in FR or FR + ex male mice was significantly rescued by treatment with active vitamin D analogues, with significant restoration of osteoblastic activities. Serum levels of insulin-like growth factor I (IGF-I), which is critical for bone remodeling, were significantly lower in FR versus control male mice. CONCLUSIONS: Low energy availability puts men at risk for stress injuries as well, and low energy availability is upstream of gonadal dysfunction and osteoporosis in males. Active vitamin D analogues could serve as therapeutic or preventive options for stress injuries in men.

Endocrine-disrupting chemicals (EDCs) and cancer: new perspectives on an old relationship.

PURPOSE: Environmental endocrine-disrupting chemicals (EDCs) are a mixture of chemical compounds capable to interfere with endocrine axis at different levels and to which population is daily exposed. This paper aims to review the relationship between EDCs and breast, prostate, testicle, ovary, and thyroid cancer, discussing carcinogenic activity of known EDCs, while evaluating the impact on public health. METHODS: A literature review regarding EDCs and cancer was carried out with particular interest on meta-analysis and human studies. RESULTS: The definition of EDCs has been changed through years, and currently there are no common criteria to test new chemicals to clarify their possible carcinogenic activity. Moreover, it is difficult to assess the full impact of human exposure to EDCs because adverse effects develop latently and manifest at different ages, even if preclinical and clinical evidence suggest that developing fetus and neonates are most vulnerable to endocrine disruption. CONCLUSION: EDCs represent a major environmental and health issue that has a role in cancer development. There are currently some EDCs that can be considered as carcinogenic, like dioxin and cadmium for breast and thyroid cancer; arsenic, asbestos, and dioxin for prostate cancer; and organochlorines/organohalogens for testicular cancer. New evidence supports the role of other EDCs as possible carcinogenic and pregnant women should avoid risk area and exposure. The relationship between EDCs and cancer supports the need for effective prevention policies increasing public awareness.

Diagnostic yield and safety of ultrasound-guided percutaneous testicular biopsies in children.

BACKGROUND: Traditionally, testicular biopsy is performed using an open surgical approach. Ultrasound-guided percutaneous biopsy is a less invasive alternative and can be performed in children. OBJECTIVE: The aim of this study is to report our technique and to assess the diagnostic accuracy and safety of ultrasound-guided percutaneous biopsy of testicular masses in children. MATERIALS AND METHODS: This is a 16-year retrospective review of ultrasound-guided percutaneous testicular biopsies at a single pediatric hospital. RESULTS: We performed nine ultrasound-guided testicular biopsies in 9 patients (median age: 3 years, range: 4 months-11 years; median weight: 20.9 kg, range: 8.4-35 kg; median volume of testicular lesion biopsied: 4.4 mL, range: 1.2-17 mL). A percutaneous co-axial technique was used for 5/9 biopsies with absorbable gelatin sponge tract embolization performed in 4 of those biopsies. A non-co-axial technique was used in 4/9 biopsies. A median of three cores, range 2-6, were obtained. The diagnostic yield was 89% with one biopsy yielding material suggestive of, but insufficient for, a definitive diagnosis. The most common histological diagnosis was leukemic infiltration, occurring in 6/9 biopsies. Of the remaining three biopsies, one biopsy was suggestive of, but not confirmatory for, juvenile granulosa cell tumor and two biopsies confirmed normal testicular tissue; the long-term follow-up of which demonstrated normal growth and no lasting damage. There was one (clinically insignificant) complication out of nine biopsies (11%, 95% confidence interval 0-44%): a mild, self-resolving scrotal hematoma. CONCLUSION: Ultrasound-guided testicular biopsy can be performed safely in children as an alternative to open surgical biopsy, with a high diagnostic yield and low complication rate.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection by Intranasal or Intratesticular Route Induces Testicular Damage.

BACKGROUND: The role of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the pathogenesis of testicular damage is uncertain. METHODS: We investigated the virological, pathological, and immunological changes in testes of hamsters challenged by wild-type SARS-CoV-2 and its variants with intranasal or direct testicular inoculation using influenza virus A(H1N1)pdm09 as control. RESULTS: Besides self-limiting respiratory tract infection, intranasal SARS-CoV-2 challenge caused acute decrease in sperm count, serum testosterone and inhibin B at 4-7 days after infection; and chronic reduction in testicular size and weight, and serum sex hormone at 42-120 days after infection. Acute histopathological damage with worsening degree of testicular inflammation, hemorrhage, necrosis, degeneration of seminiferous tubules, and disruption of orderly spermatogenesis were seen with increasing virus inoculum. Degeneration and death of Sertoli and Leydig cells were found. Although viral loads and SARS-CoV-2 nucleocapsid protein expression were markedly lower in testicular than in lung tissues, direct intratesticular injection of SARS-CoV-2 demonstrated nucleocapsid expressing interstitial cells and epididymal epithelial cells, While intranasal or intratesticular challenge by A(H1N1)pdm09 control showed no testicular infection or damage. From 7 to 120 days after infection, degeneration and apoptosis of seminiferous tubules, immune complex deposition, and depletion of spermatogenic cell and spermatozoa persisted. Intranasal challenge with Omicron and Delta variants could also induce similar testicular changes. This testicular damage can be prevented by vaccination. CONCLUSIONS: SARS-CoV-2 can cause acute testicular damage with subsequent chronic asymmetric testicular atrophy and associated hormonal changes despite a self-limiting pneumonia in hamsters. Awareness of possible hypogonadism and subfertility is important in managing convalescent coronavirus disease 2019 in men.

Contrast-enhanced and microvascular ultrasound imaging features of testicular lymphoma: report of five cases and review literature.

BACKGROUND: To retrospectively investigate the grey-scale, Doppler, contrast-enhanced and microvascular ultrasound of five patients with primary testicular lymphoma of our institute through review literature analysis. METHODS: From January to November 2020, five patients with primary testicular lymphoma confirmed by histology were preoperatively investigated with a standardized sonographic protocol including contrast-enhanced and microvascular ultrasound. RESULTS: Conventional ultrasound showed localized hypoechogenicity represented with solitary (2 of 5), multiple lesions (2 of 5), or entire testicular involvement (1 of 5). Increased blood flow appeared in color Doppler ultrasound with straight vascular sign (4 of 5). In contrast-enhanced ultrasound images confirmed this pattern (4 of 5) and presented hyper enhancement with enlarged range. On microvascular ultrasound imagings, all lesions were presented with straight and parallel course of intralesional vessels (5 of 5). CONCLUSIONS: Here, we identified an increased vascularity with enlarged range on contrast-enhanced ultrasound along with a linear nonbranching pattern by vascular sign on microvascular ultrasonographic of testicular lymphoma.

Medullary bone in male budgerigars (Melopsittacus undulatus) with testicular neoplasms.

Medullary bone is a calcium-rich, labile bone normally occurring in female birds with each egg-laying cycle. The stimulus for formation of medullary bone is, in part, the cyclic increase in serum estrogens produced by preovulatory ovarian follicles. Increased bone density due to formation of medullary bone, particularly in pneumatic bones, has been termed polyostotic hyperostosis, even if physiologic. This study investigated the formation of medullary bone in nonpneumatic (femur) and pneumatic (humerus) bones in sexually mature male budgerigars submitted for autopsy. Of the 21 sexually mature male budgerigars submitted for autopsy, 7 (33%) had medullary bone in 1 or more bones examined. All 7 male budgerigars with medullary bone had a testicular neoplasm, which was morphologically consistent with a testicular sustentacular cell tumor, seminoma, or interstitial cell tumor. Medullary bone was not present in the 14 cases with other diseases. Medullary bone formation in pneumatic and nonpneumatic bones can occur in male budgerigars with testicular neoplasms. Radiographic increases in medullary bone density, particularly in the humerus, could provide antemortem indication of testicular neoplasia in male budgerigars.

The effect of Fumaria parviflora on the expression of sexual hormones along with their receptors in testicles of adult rats induced by varicocele.

Varicocele (VCL) is a pathological dilation of the venous pampiniform plexus of the spermatic cord and is also classified as male factor infertility. The current experiment aimed to examine the protective effect of Fumaria parviflora (FP), as a powerful antioxidant, against reproductive damage induced by VCL. In this experimental study, 32 male rats were randomly allocated into four groups, namely sham (simple laparotomy without additional intervention), FP (healthy rats administered 250 mg/kg FP), VCL + FP (underwent VCL and received 250 mg/kg FP), VCL (underwent VCL without receiving any treatment). The results showed that the number of Sertoli and germ cells were markedly reduced in the VCL group in comparison to the FP-treated and sham groups. The VCl + FP group had significantly higher serum levels of testosterone (T), FSH, and LH hormones than the VCL group. The quality and motility of spermatozoa were reduced in the VCL group compared with other groups (p ≤ 0.05). Moreover, our findings demonstrated that the administration of FP considerably enhanced the mRNA levels of CatSper-1 and -2, SF-1, 3ß-HSD, 17ß-HSD3, LHCGR, and FSHR (p ≤ 0.05). Based on the obtained results, treatment with FP is capable of preventing testicular dysfunction and elevating the concentration of hormones and some crucial genes, such as CatSper1 and 2, SF-1, 3ß-HSD, 17ß-HSD3, LHCGR, and FSHR that contribute to the spermatogenesis process.

Impact of high fat diet on the sterol regulatory element-binding protein 2 cholesterol pathway in the testicle.

Male fertility has been shown to be dependent on cholesterol homeostasis. This lipid is essential for testosterone synthesis and spermatogenesis, but its levels must be maintained in an optimal range for proper testicular function. In particular, sperm cells' development is very sensitive to high cholesterol levels, noticeably during acrosomal formation. The aim of this work was to study whether the molecular pathway that regulates intracellular cholesterol, the sterol regulatory element-binding protein (SREBP) pathway, is affected in the testicles of animals under a fat diet. To investigate this, we took advantage of the non-obese hypercholesterolemia (HC) model in New Zealand rabbits that displays poor sperm and seminal quality. The testicular expression of SREBP isoform 2 (SREBP2) and its target molecules 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMGCR) and low-density lipoprotein receptor (LDLR) were studied under acute (6 months) and chronic (more than 12 months) fat intake by RT-PCR, western blot and immunofluorescence. Our findings showed that fat consumption promoted down-regulation of the SREBP2 pathway in the testicle at 6 months, but upregulation after a chronic period. This was consistent with load of testicular cholesterol, assessed by filipin staining. In conclusion, the intracellular pathway that regulates cholesterol levels in the testicle is sensitive to dietary fats, and behaves differently depending on the duration of consumption: it has a short-term protective effect, but became deregulated in the long term, ultimately leading to a detrimental situation. These results will contribute to the understanding of the basic mechanisms of the effect of fat consumption in humans with idiopathic infertility.

Establishing Normal Testicular 18F-FDG PET/CT SUVs.

OBJECTIVE. Knowledge of normal testicular 18F-FDG PET/CT (FDG PET/CT) SUVs is crucial for accurate examination interpretation. The objective of this study was to establish normal testicular SUV ranges among adult men receiving health care in North America. MATERIALS AND METHODS. A retrospective review of an institutional electronic database identified adult men undergoing pretreatment clinical FDG PET/CT examinations from March 15, 2013, through March 15, 2018. An FDG PET/CT image review of 700 testicles in 350 male patients was performed. Data collected included testicular SUVmax, SUVmean, and visual PET pattern of uptake. RESULTS. Testicular SUVmean and SUVmax values (mean ± SD) by age group were as follows: 3.1 ± 0.7 and 3.8 ± 0.9 for the age group of 18-30 years; 3.2 ± 0.6 and 4.0 ± 0.8, 31-40 years; 3.1 ± 0.4 and 3.8 ± 0.5, 41-50 years; 3.0 ± 0.5 and 3.7 ± 0.7, 51-60 years; 2.9 ± 0.5 and 3.5 ± 0.7, 61-70 years; 2.8 ± 0.5 and 3.5 ± 0.7, 71-80 years; and 2.6 ± 0.5 and 3.3 ± 0.6, more than 80 years. A statistically significant difference exists between age groups for testicular SUVmean (p ≤ .001) and SUVmax (p < .001), with SUVs peaking in the 4th decade of life and subsequently declining with age. A small but significant negative correlation exists between blood glucose level and testicular SUVmean (r = -0.12). CONCLUSION. This study reports the largest currently known cohort of SUVs in normal testicles and may guide clinical interpretation of testicular FDG activity. Discrepancies in normal SUVs may exist because of differences in patient demographics and PET technology.

Intracerebroventricular salusin-ß infusion to rats increases hypothalamus-pituitary-testicular axis hormones.

Salusin-ß (Sal-ß), which originates from preprosalusin, is a multifunctional hormone with a peptide structure. Sal-ß exists in the hypothalamus and can stimulate the pituitary gland. The present study was conducted to determine the effects of Sal-ß on hormones that play roles in the male reproductive system. Forty male Wistar Albino rats were used in the study. No infusions were performed on the control group, and infusions were applied to the infusion groups (artificial cerebrospinal fluid to the sham group, 2 and 20 nM Sal-ß to the experimental group) through intracerebroventricular infusion for 7 days at 10 µl/hour rate. The animals were decapitated after 7 days of infusion; and the hypothalamus, testicles, and blood tissue samples were collected. The gonadotropin-releasing hormone (GnRH) mRNA levels were determined from the hypothalamus tissues by using the Real Time-PCR Method, and the serum luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone levels were determined using the ELISA method. Also, Hematoxylin-Eosin Staining Method was used for histopathological evaluations in the testicle tissues. As a result, Sal-ß infusion increased GnRH mRNA levels in hypothalamus tissues (p < 0.05) besides, serum LH, FSH, and testosterone levels of the rats were higher at significant levels following Sal-ß infusion compared to the control and sham group (p < 0.05). In the histological examination of the testicle tissues, Sal-ß application was found to decrease the seminiferous tubule diameter and germinal epithelial thickness (p < 0.05). This evidence is the first, indicating that Sal-ß, which is administered to male rats with central infusion, stimulates hypothalamus and pituitary tissues, and causes increased secretion of male reproductive hormones.

Staged Fowler Stephens, Who Requires a Third Procedure?

PURPOSE OF REVIEW: The two-stage Fowler-Stephens orchiopexy is a well-described surgical approach for most pediatric urologists tackling the high intra-abdominal testis. Testicular ascent is a well-reported outcome of the surgery and a problem that could be fixed with a repeat procedure. The purpose of this review is to determine the rate of subsequent testicular ascent and repeat surgery after a two-stage Fowler-Stephens using best available evidence. RECENT FINDINGS/RESULT: We selected 16 studies that pertained to our topic. 0-13% of testicles were deemed to be in an inappropriate position on follow-up (6-37 months). The definition of appropriate postoperative position varied between studies and rates of repeat procedures were sparsely available. Available data reports a repeat orchiopexy rate of 2.6-7.5% after two-stage Fowler-Stephens. Two-stage Fowler-Stephens orchiopexy is a highly successful surgical technique to manage high intra-abdominal testes. Rates of testicular ascent are difficult to ascertain due to varying definitions and small sample sizes. While repeat procedures are typically indicated, the actual rate of repeat orchiopexy is rarely reported and long-term outcomes following a third procedure is sparse.

Usual or unusual presentations of Dirofilaria repens in two sibling dogs: a case report.

This study describes two different manifestations of Dirofilaria repens infection in sibling dogs with microfilaremia. Dog 1, asymptomatic, harbored a gravid female of D. repens on the parietal layer of tunica vaginalis of one testicle and showed a marked circulating eosinophilia (3.3·103/µL). Both testicles were normal in shape and size without any gross lesions. Dog 2 had a pyotraumatic dermatitis. The cases were confirmed by PCR and sequencing. The sequences obtained showed 100% identity with those of D. repens isolated from human scrotum in Croatia. The treatment with moxidectin 2.5% and imidacloprid 10%/kg was effective in eliminating microfilariae after just one application, as demonstrated by negative modified Knott's tests and PCR analyses of blood samples. This status was maintained during the post-treatment observation period. The classical localization of D. repens in dogs is in subcutaneous tissues, within nodules or free; however, it can also occur with some frequency in testicles, as described in humans. The infection can be associated with circulating eosinophilia or pyotraumatic dermatitis, as reported in this study. Thus, in endemic areas, it is advisable to carefully inspect the removed testicles at neutering since parasite localization can take place without any macroscopic changes. Moreover, in the case of circulating eosinophilia or pyotraumatic dermatitis, investigations should include modified Knott's test and PCR to ensure that D. repens is not the cause of these alterations. Rapid and sensitive tests for the early detection of infected animals would help to prevent or limit the spread of this zoonosis.

Differentially expressed microRNA in testicular tissues of hyperuricaemia rats.

This study is to identify the differentially expressed miRNAs in testicular tissues of rats with hyperuricaemia-induced male infertility. We found that the hyperuricaemia model group had significantly increased serum uric acid, while significantly decreased sperm concentration and motile sperm percentage than normal group (p < .05). A total of 39 differentially expressed miRNAs were identified in the testicular tissues of hyperuricaemia rats compared with the control rats, ten of which were validated by real-time PCR. The target mRNAs of 7 differentially expressed miRNAs (miR-10b-5p, miR-26a-5p, miR-136-5p, miR-151-3p, miR-183-5p, miR-362-3p and miR-509-5p) from 3'-untranslated region binding perspective were enriched in signalling pathways of Wnt, Jak-STAT, mTOR and MAPK. The target mRNAs of 6 differentially expressed miRNAs (miR-136-5p, miR-144-3p, miR-99a-5p, miR-509-5p, miR-451-5p and miR-362-3p) from coding sequence binding perspective were enriched in signalling pathways of Calcium, Notch and MAPK. The functions of miRNAs in testicular tissues of rats with hyperuricaemia were revealed by the differentially expressed miRNAs (miR-183-5p, miR-99a-5p, miR-10b-5p, miR-151-3p, miR-26a-5p, miR-451-5p, miR-362-3p, miR-136-5p, miR-144-3p and miR-509-5p)-mRNAs interaction network. The differentially expressed miRNAs in the testicular tissues of hyperuricaemia rats might shed light on the mechanism of hyperuricaemia-induced male infertility.

Feminising hormone therapy reduces testicular ACE-2 receptor expression: Implications for treatment or prevention of COVID-19 infection in men.

It has been proposed that men hospitalised with COVID-19 be treated with oestrogen or progesterone to improve COVID-19 outcomes. Transgender women (male-to-female) are routinely treated with oestrogen or oestrogen +progesterone for feminisation which provides a model for the effect of feminising hormones on testicular tissue. Our goal was to analyse differences in ACE-2 expression in testicles of trans-women taking oestrogen or oestrogen +progesterone. Orchiectomy specimens were collected from trans-women undergoing gender-affirming surgery, who were taking oestrogen or oestrogen+progesterone preoperatively. For controls, we used benign orchiectomy specimens from cis-gender men. All specimens were stained with H&E, Trichrome (fibrosis), insulin-like 3 antibody (Leydig cell) and ACE-2 IHC. Cells per high-powered field were counted by cell type (Leydig, Sertoli and Germ). Stain intensity was rated on a 0-2 scale. On immunohistochemistry staining for Leydig cells and ACE-2 staining, the oestrogen+progesterone cohort had fewer Leydig cells compared with controls. The oestrogen+progesterone cohort also had greater degree of tissue fibrosis compared with controls and the oestrogen cohort. This work supports the hopeful possibility that a short course of progesterone (or oestrogen+progesterone) could downregulate ACE-2 to protect men from COVID-19 infection.

Influence of different warming temperatures on the vitrified testicular fragments from pre-pubertal cat.

Testicular vitrification is an alternative to preserve the genetic material of pre-pubertal animals. However, there are few studies on post-vitrification warming. Hence, the aim was to compare the influence of different warming temperatures on vitrified testicular fragments from pre-pubertal cats. The testicles were fragmented and divided into a control group (non-vitrified) and vitrified, using an association between dimethylsulphoxide and glycerol. The vitrified fragments were warmed at 50, 55 and 60°C/5 s. Morphological and morphometric evaluations were carried out using classical histology. Afterwards, the mitochondrial activity was evaluated using Rhodamine 123. The data were expressed in mean and standard error. The differences were considered significant when p < .05. In the histomorphological analysis, the testicular fragment presented seminiferous tubules with poorly developed germinal epithelium, compatible with pre-pubertal animals. The group warmed at 50°C presented similar to the control regarding the maintenance of the integrity of the tubules and cells, without stromal rupture and lamina propria alteration, as well as regarding the maintenance of the junctions between the cells. The group warmed at 55°C showed reduction of the cell junctions, and the one warmed at 60°C had increased detachment of the basement membrane (p < .05). The warming caused a reduction in the tubular diameter inversely proportional and progressive to the increase in temperature, with the highest diameter in the control group and the lowest in the 60°C group. The control group showed a lower incidence of Rhodamine 123, followed in ascending order of the warmings at 55 and 60°C. The higher mitochondrial activity was obtained with 50°C, showing an increase of the metabolic cell function at this temperature. It was concluded that the testicular fragment of pre-pubertal cats presents a better preserved morphology, morphometry and viability when warmed at 50°C.

Testicular Changes of Honey Bee Drones, Apis mellifera (Hymenoptera: Apidae), During Sexual Maturation.

The normal developmental anatomy and histology of the reproductive tract of the honey bee drone, Apis mellifera (Linnaeus, 1758), has been well documented. The post-emergence maturation changes of the accessory glands are likewise well understood, but the normal histological changes of the testicle undergoing physiologic atrophy are not well characterized. To address this knowledge gap, herein we describe the anatomy and sequential histological stages of normal testicular atrophy of drones sampled daily from emergence to sexual maturity in the spring (June) and early summer (July). Testicular histological changes during maturation are characterized by the following stages: I) conclusion of spermiogenesis; II) evacuation of spermatodesms from tubular lumens; III) progressive follicular cell atrophy, and IV) complete atrophy and collapse of testicular parenchyma. Tubular changes occur in a basilar to apical direction where segments closer to the vas deferens are histologically more mature than corresponding apical segments. In addition, the rate of testicular maturation was found to change with seasonal progression. This description of physiologic testicular atrophy should be useful for future studies investigating potential pathological effects of stressors on drone testes during sexual maturation.

Testicular thermoregulation with respect to spermatogenesis and contraception.

There has been some evidence that a short heating exposure of the testicles can lead to temporary sterility. However, little attention has been paid to analyzing the temperature/time pattern throughout the testicle and how metabolism and blood perfusion affect the temperature profile. We use the Penne bioheat equation that accounts for the elements of conduction, perfusion, and metabolism along with the COMSOL Finite Element Method for the analysis of this thermoregulation problem. Typically, the testicles were modeled as two uniform spheres and exposed to an increase in surface temperature of 42 °C for 30 min. We found that heat produced by tissue metabolism had a minor effect on the temperature pattern. However, blood flow from the core (at 37 °C) could prevent the region where the testicles touch each other from reaching the target temperature of 42 °C. Further, we found that for animals, as rodents and monkeys that are used for contraception studies, the temperature distribution on heating testicles is much more uniform than for humans. Thus, extrapolation results from animal models to humans should be done with caution.