[Study of the effect of the herbicide 2,4-DM on the pregnant body, embryonic development on gonadal function in white rats].
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2,4-Dichlorophenoxyacetic Acid↗
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[Host-parasite interactions between Coccus hesperidum L. (Hom. Coccidae) and its parasite Coccophagus scutellaris Dalman (Hym. Aphelinidae)].
The eggs laid in the host gut will develop normally. The larva resulting from those eggs penetrate the hemocele through the gut wall. The structure of the cells near the entry point is not affected because of the continuous renewal of those cells. On the other hand, development of the ovaries is most seriously affected. In fact, ovogenesis is stopped and vitellogenesis slowed down. But this phenomenon is related to the initial level of ovary development. If the attack takes place when the host is young, the effect on the ovaries is more serious. In extreme cases gonad development is annihilated. Otherwise, the host will still be able to lay eggs, but its reproduction capacity is diminished. Factors reducing development of gonads or maintaining them at a juvenile stage are discussed.
Animals↗
Sexually dimorphic expression and hormonal responsiveness of steroidogenic Cyp genes during gonadal differentiation in mandarin fish.
Steroid hormones play a pivotal role in fish sex differentiation, yet the dynamic expression patterns of key steroidogenic enzymes during this process remain incompletely characterized. Here, we combined genome-wide identification, time series transcriptomes spanning gonadal development (5-360 days post-hatch), and multiple hormone treatment experiments (17α-methyltestosterone, estrone, and etonogestrel) to investigate the Cyp11, Cyp17, Cyp19, and Cyp21 subfamilies in mandarin fish (Siniperca chuatsi). Seven steroidogenic Cyp genes were identified, showing teleost-specific expansion, with one duplicated pair (cyp17a2 and cyp2u1) exhibiting strong purifying selection. Expression profiling revealed pronounced sexually dimorphic and stage-specific patterns: During female differentiation (20-30 days), cyp19a1a and associated genes were highly expressed, coinciding with ovarian differentiation; during male differentiation (30-60 days), cyp17a2 and related genes were upregulated, aligning with testicular development. Exogenous hormone treatments further demonstrated that these genes are dynamically responsive: cyp19a1a and cyp17a2 were highly responsive to androgenic and progestogenic treatments, and their expression changes correlated closely with gonadal sex reversal phenotypes observed histologically. Collectively, this study provides a comprehensive expression atlas of steroidogenic Cyp genes during gonadal differentiation and identifies key hormonally responsive candidates for sex control in aquaculture.
Animals↗
[A special gonad protector for comparative radiograms of the hips in infants (authors transl)].
A special, newly developed, gonad protector to be used for comparative radiograms of the hips in infants was introduced. This lead protector has a window which, due to its special shape, exposes only that portion of the skeleton which is important for the evaluation of dysplasia of the hip. In order to better protect the testes from scattered rays, a trough shaped lead plate is placed behind the scrotum.
Age Factors↗
[Pure gonadal dysgenesis. Case report with unusual anatomical and endocrine findings].
The syndrome of pure gonadal dysgenesis (PGD) cannot always easily be distinguished from other disorders of gonadal development. Relations are evident with Turner's syndrome, females with hypoplastic ovaries, male pseudohermaphroditism, mixed gonadal dysgenesis and the vanishing testes syndrome. The case is reported of a 40 year old female with primary amenorrhea, alopecia, eunuchoid features, XY karyotype with normal breast development and sexual hair after estrogen therapy. On laparotomy streak ovaries were found at ovarian site. Pathohistological examination revealed on the left side wolffian duct remnants such as ductuli deferentes and epididymis besides sparse Leydig-(hilus-)cells and on the right side only a rudimentary fallopian tube with subendothelial accumulation of hyperplastic Leydig-(hilus-)cells. Serum-testosterone elevation above the normal female range (630 ng/dl) persisted following gonadectomy (151 ng/dl). Ectopic Leydig-(hilus-)cells were regarded responsible for the continuing testosterone production. The present case lies on borderline between PGD and mixed gonadal dysgenesis because remnants of wolffian duct derivatives suggest unilateral fetal testicular activity; classification as PGD however was justified in purely female body features and lacking evidence of testicular tissue.
Adult↗
Human testicular development and the role of the mesonephros in the origin of a dual Sertoli cell system.
Some aspects of the development of the human testis (and overy) are discussed and the main theories regarding gonadal differentiation summarized. The major part of this review deals with the origin and differentiation of the three groups of somatic cellular content: Sertoli cells, Leydig cells and peritubular cells. The most important role of the mesonephros in gonadal development is described. Under the influence of the mesonephros, a second type of meiosis-inducing Sertoli cell differentiates and becomes the opponent of a meiosis-preventing type of Sertoli cell which derives from the coelomic epithelium. All somatic cells are pooled in the central gonadal blastema which is part of the medulla. They migrate via the rete blastema to the sites of their final differentiation. Included are the precursors of the Leydig cells and the peritubular cells.
Cell Differentiation↗
[Two rare congenital malformations of the female urethra].
Two cases of incontinent females due to malformations of the dorsal wall of the urethra are presented and surgical corrections are discribed. The causal factors for the development of the malformations are explained by irregularities of the Wolffian ducts' regression during the transition period between in gonadal development between the 3rd and 5th week of gestation. The new medical technical term "indifference-syndrome" is proposed, to distuingish these malformations of the female urethra from true hypospadia.
Child, Preschool↗
Isochromosome Yq in a woman with atypical Turner's syndrome.
A female with 46,X,i(Yq) in all cells and a survey of previous cases of isochromosome Yq is presented. She was first admitted to hospital 15 years old due to nanismus and retarded sexual development. Gonadal dysgenesia was observed, and the diagnosis 'atypical Turner's syndrome' was applied. The patient, who presents only a few Turner stigmata, has been given cyclic estrogen treatment since the age of 16. She has developed normal secondary sex characteristics, cyclic bleedings and has attained normal height (161 cm). Since the age of 18 the patient has suffered various periods of anemia caused by gastrointestinal hemorrhage. This hemorrhage is probably due to intestinal teleangiectasiae which are found with increased frequency in patients with Turner's syndrome.
Adult↗
Mismatch repair protein MLH1 controls testis development by regulating the Hippo-YAP signaling pathway.
DNA mismatch repair (MMR) maintains genomic stability, and defects in MMR genes such as MLH1 and MSH2 predispose to cancer. Unlike other MMR components, MLH1 has unexplained roles in development, as Mlh1-deficient male mice exhibit severe testicular hypoplasia and sterility. Here, we uncover that MLH1 regulates testis development through the Hippo-Yes-associated protein (YAP) pathway. MLH1 directly binds YAP via its C-terminal domain and the WW domains of YAP, competitively inhibiting LATS1-mediated YAP phosphorylation. This interaction stabilizes YAP by suppressing ubiquitination and promotes its nuclear translocation dependent on MLH1's nuclear localization signal. Additionally, MLH1 facilitates YAP-TEAD complex formation, enabling expression of testicular development genes, including Wt1, Sox9, and Ctgf. These functions are independent of the MMR activity of MLH1. Mlh1-deficient mice show elevated YAP phosphorylation, reduced target gene expression, and impaired proliferation in developing testes. Pharmacological inhibition of the Hippo pathway kinases MST1/2 partially rescues testis hypoplasia in Mlh1-/- mice. These findings establish MLH1 as a Hippo pathway regulator and resolve its long-standing role in male gonad development.
Male↗
Qualitative distribution of neutral lipids and phospholipids in Hymenolepis microstoma from the cysticercoid to the egg producing adult.
The distribution of neutral lipids and phospholipids in Hymenolepis microstoma has been studied using Fettrot, Sudan Black B, Sudan IV and copper phthalocyanin staining techniques. In the cysticercoid, neutral lipids are found in the outer membrane, the lining of the cysticercoid cavity, the tegument of the larval worm and the calcareous corpuscles. A decreasing gradient of phospholipids is found starting from the acellular layer, through the circular fibrous layer, the longitudinal fibrous layer, the adjacent dense zone and ending with the lining of the cysticercoid cavity. Phospholipids are also found in the calcareous corpuscles and the tegument of the larval worm. In the young adult (3 days p.i.) fat globules are first seen to accumulate in the last 2-3 proglottids. Until the 6th day p.i. they are found in the posterior third of the worm, surrounding developing gonads, but mostly concentrated along the transverse line. The mature proglottids contain fat, (a) in both granular and globular forms: in the folds of the uterus, sperm ducts, cirrus pouch and tegument (proximal cytoplasm), (b) in a diffuse form: in the vitellaria, ovary, testes and the tegument (distal cytoplasm). Pre-gravid and gravid proglottids show the largest fat globules. From the cleaving embryo to the fully developed oncosphere the concentrations of neutral lipids and phospholipids vary in form, intensity and location. In all strobilar forms of the parasite neutral lipids and phospholipids are found in the tegument and calcareous corpuscles. Although in H. microstoma lipid droplets are found in the excretory canals, all lipids in the proglottids are not absolutely waste products. From the results it would appear that they play a role in the maturation of gonads and transformation of the fertilized ovum to the oncosphere.
Animals↗
Ligand-based directed differentiation to produce granulosa-like cells expressing steroidogenic enzyme genes.
The ovarian granulosa cells are responsible for producing hormones and supporting oocytes through maturation and meiotic resumption. There is a need to generate granulosa-like cells (GLCs) from human induced pluripotent stem cells (hiPSCs) to better model human gonadal development and to test the effects of exogenous or pharmaceutical compounds on the ovary. Here we report a rapid ligand-based protocol for differentiating hiPSCs into cells that express markers of the transient developmental lineages and steroidogenic pathway genes. Single-cell RNA-sequencing (scRNA-seq) analysis identified canonical granulosa cell genes were expressed in a subset of cells and identified new genes of interest that were significantly associated with computationally modeled pseudotime. HSD17B1 was expressed in resulting GLCs but at low levels, suggesting an immature granulosa cell phenotype. The GLCs were produced using a simple culture method that could be augmented for granulosa cell functions such as sustaining oocyte growth. Producing GLCs through protocols such as this one is a first step toward designing large-scale ovarian endocrinology assays and developing personalized cell-based fertility and hormone restoration technologies in the future. This rapid protocol produced cells that express steroidogenic enzyme genes etoc blurb. Kubo and colleagues present a 5-day rapid protocol to generate immature granulosa-like cells from hiPSCs. Cells differentiated with inhibition of DKK1, a WNT signaling target gene, expressed gonadal ridge markers and FOXL2 transcripts and protein. Additionally, steroidogenic enzyme genes were expressed. A small population of differentiated cells were identified as expressing early-stage granulosa cell genes by single-cell RNA-seq.
Female↗
A reciprocal translocation (X;11) in a female with gonadal dysgenesis.
A 24-year-old female patient was referred for evaluation of primary amenorrhea. Endocrine studies showed elevated gonadotropins, consistent with gonadal failure. At laparoscopy, a normal nulligravid uterus, normal fallopian tubes, and bilateral streak gonads were observed. Histologic studies showed that the left gonad consisted entirely of fibrous tissue, confirming the presence of streak gonads. Chromosome banding studies of peripheral blood and cultures of tissue from the left gonad demonstrated a 46,X,rcp(X;11)(q22;q13) karyotype. A review of reports of X-autosome reciprocal translocations indicated that abnormal gonadal development is associated with break-points in the mid-region of the long arm of the X chromosome.
Adult↗
A study of gonadal organogenesis, and the factors influencing regeneration following surgical castration in Deroceras reticulatum (Pulmonata:Limacidae).
At hatching, the hermaphrodite duct of Deroceras reticulatum consists of a single cell type designated the Gonadal Stem Cell (GSC). Proliferation of the GSC leads to the formation of numerous ductules each of which forms one of the acini of the gonad. The germinal and supporting cells are derived entirely from the GSC. The germ cells differentiate first, followed by the Sertoli and follicle cells. At the early sperm stage of gonadal development the hermaphrodite duct differentiates to function as a seminal vesicle. Once the GSC are committed to this change they lose their regenerative ability. The only remaining GSC are the cells of the acinar epithelium, and these retain their germinal potential until the death of the animal. Regeneration will occur from the hermaphrodite duct provided it is in the immature state, i.e., composed of GSC, and is exposed to the hormonal conditions of a young animal. Nervous connections and the presence of an artery are not necessary for this regeneration. The presence of a functional gonad does not inhibit regeneration.
Animals↗
[Coelomic gonadal epithelia during the period of human embryonic morphologic sex differentiation].
The course of divergent differentiation of coelomic epithelium in the indifferent gonad has been traced up to the stage when morphological sex signs are distinctly seen. Eleven human embryos fixed in Carnoy and Bouin's fluid have been studied from 6 to 10 weeks of gestation. Paraffin sections were stained with hematoxylin, ferric hematoxylin after Heidenhain. Basal membrane fibres were revealed by silver impregnation after Karupu. PAS-reaction after McManus and additional staining with hematoxylin and light green were applied, as well as the reaction for total proteins with bromphenol blue after Miguel--Calvo. Sex differentiation of coelomic epithelium in the gonad developing according to the male type begins a little later than in the ovary. In the epithelium of the forming testis a great amount of mitotic figures is observed that might be connected with the presence of Y-chromosome stimulating cells for extra mitotic cycles. The increasing presence of Y-chromosome stimulating cells for extra mitotic cycles. The increasing number of mitotic figures in the epithelium should be considered as a sign demonstrating that differentiation according to the male type has started. Superficial epithelium of the embryonic ovary has a peculiar false pseudostratified structure. This secures cellular reserve for the ovarian cortex formation from the external epithelium. The apical surface of the cells in the external epithelium has a border which is evidently formed by microvilli and revealed by PAS-reaction and bromphenol blue. Ovarian follicular cells and Sertoli's cells (sustentocytes) in testis have the common origin in the human fetus--from coelomic epithelium of the gonad germ.
Epithelial Cells↗
Breed differences in abnormalities of the reproductive organs of young beef bulls.
A total of 702 examinations were conducted on young (16 to 31 months) beef bulls of 3 breeds and 3 breed crosses (Brahman cross--100; Africander cross--93; Shorthorn cross--109; Brahman--81; Africander--89, and Hereford--230). A high occurrence of both increased size (overall 11.7%) and consistency (overall 40.2%) of seminal vesicles was observed. The Hereford breed had most enlarged (19.1%, P less than .01) and firm (20.9%, P less than .01) seminal vesicles. The significance of these findings is discussed. Testicular hypoplasia was diagnosed in 2.7% of examinations. The Brahman breed had most testicular hypoplasia (8.6%, P less than .01). The implications of this finding are discussed and the need is stressed for a wider investigation of gonad development in the Brahman breed in Australia. Other findings included: small seminal vesicles in 1.6% of examinations (Brahman breed highest with 8.6%, P less than .001), enlarged ampullae, 1.9%, 'soft' testicles, 3.4% and small testicles, 7.5%. Abnormal carriage of the testicles was detected in 0.3% of examinations. Ulceration of the prepuce was observed in 6.8% of examinations. The highest occurrences were in the SH (13.8%, P less than .01) and Africander (13.5%, P less than .05) breed groups. Varying degrees of preputial eversion or prolapse were seen in 0.7% of examinations with the Bx breed group having highest representation (3.0%, P less than .05).
Animals↗
Changes in the activity of the ependyma in the infundibular recess of the brain of Rana esculenta L. in the annual cycle.
Volume of the cell nuclei of the ependyma of the infundibular recess was measured in 30 female and 30 male water frogs (Rana esculenta L.) obtained from their natural environment, taking into account the phase of the annual cycle. Karyometry of the ependymal cell nuclei in the infundibular recess in males and females showed statistically significant differences of volume (activity) in the annual cycle. The largest volume of nuclei of the ependymal cells in females and males was observed in the first decade of April (end of hibernation), and the smallest in the first decade of September (end of the period of active life). Activity of nuclei of cells from the infundibular recess clearly correlated with gonadal development.
Activity Cycles↗
Electron microscopic studies on the structure of motile primordial germ cells of Xenopus laevis in vitro.
Primordial germ cells (PGCs) of Xenopus laevis have been isolated from early embryos and kept alive in vitro, in order to study the structural basis of their motility, using the transmission and scanning electron microscope. The culture conditions used mimicked as closely as possible the in vivo environment of migrating PGCs, in that isolated PGCs were seeded onto monolayers of amphibian mesentery cells. In these conditions we have demonstrated that: (a) No significant differences were found between the morphology of PGCs in vitro and in vivo. (b) Structural features involved in PGC movement in vitro include (i) the presence of a filamentous substructure, (ii) filipodial and blunt cell processes, (iii) cell surface specializations. These features are also characteristic of migratory PGCs studied in vivo. (c) PGCs in vitro have powers of invasion similar to those of migrating PGCs in vivo. They occasionally become completely surrounded by cells of the monolayer and, in this situation, bear striking resemblance to PGCs moving between mesentery cells to the site of the developing gonad in stage-44 tadpoles. We conclude that as far as it is possible to assess, the behaviour of isolated PGCs in these in vitro conditions mimics their activities in vivo. This allows us to study the ultrastructural basis of their migration.
Animals↗
[The localization of primordial germ cells in Japanese quail embryos using a technic of ultraviolet irradiation].
In the Japanese quail embryo at the stage of 6 pairs of somites, ultraviolet irradiation of the extraembryonic crescent-shaped area anterior to the level of the first somites does not lead to total sterilization of the developing gonads. There are always subsisting primordial germ cells which apparently can restore the population of gonocytes. On the contrary, complete sterilization can be obtained by irradiating the area extending posteriorly to the level of the Hensen node.
Animals↗