Relative Frequencies Of Stages Research Articles

Clinical pathological characteristics and treatment outcomes of renal cell carcinoma (RCC): a retrospective study from Sudan.

Worldwide, renal cell carcinoma comprises 2.2% and 1.8% of global cancer incidence and mortality, respectively. Studies of epidemiology, treatment modalities and outcomes of renal cell carcinoma (RCC) in Sudan are scarce. To address this shortcoming, we evaluated baseline information on the epidemiology, types of treatment and outcomes of RCC at Gezira Hospital for Renal Diseases and Surgery (GHRDS) and the National Cancer Institute (NCI). We performed a retrospective, descriptive study of all patients with RCC, who were treated in GHRDS and NCI from January 2000 to December 2015. A total of 189 patients with RCC were identified over the study period. Tumours were more common among male patients (56%) and involved the left kidney in 52% of cases. The median age at diagnosis was 57 years (range: 21-90 years). Loin pain was the most frequent symptom (n = 103 patients) followed by weight loss (n = 103 patients) and haematuria (n = 65 patients). The most common histopathologic type of RCC was clear cell (73.5%), followed by papillary (13.8%) and chromophobe (1.6%). The relative frequencies of stages I-IV were 3.2%, 14.3%, 29.1% and 53.4%, respectively. The overall median survival rate was 24 months, and the 5-year survival rate was 40%. The 5-year survival rate in stages I-IV was 95%, 83%, 39%, and 17%, respectively. Advanced stages and higher-grade tumour were associated with worse survival. The median survival of stage IV patients was better for patients who underwent nephrectomy (11.0 months) compared to those who did not undergo nephrectomy (4.0 months) (p value = 0.28). Our findings reveal poor outcomes for patients with RCC in Sudan, which is most likely due to the high proportion of patients presenting with advanced stages at the time of initial presentation.

Characterization of Seminiferous Epithelium Stages in the Wild Javan Muntjac (Muntiacus muntjak muntjak) Using the Tubular Morphology Method.

Stages of the seminiferous epithelium of the testis of the wild Javan muntjac (Muntiacus muntjak muntjak) in hard antler period were characterized based on the tubular morphology method. The number and the relative frequencies of seminiferous epithelium stages and the morphometry of germinal cell nuclei were identified microscopically. We identified eight stages of seminiferous epithelium in testicular tissue of the Javan muntjac and found that the relative frequencies of stages I to VIII were 14.87, 15.12, 17.75, 6.87, 7.37, 12.37, 13, and 12.62%, respectively. The diameter of the nuclei of germinal cells varied in each stage of seminiferous epithelium. Diplotene-stage primary spermatocytes had prominent and large nuclei ~8.97 ± 1.0 μm in stages III and IV. Pachytene primary spermatocytes appeared in most stages, except stage IV, whereas leptotene- and diplotene-stage primary spermatocytes were found in stages I and II, and III and IV, respectively. Round spermatids were observed in stages IV to VIII and in stage I but were absent in stages II and III, while elongated spermatids were observed in all stages except stage I. Our findings show that the stages of seminiferous epithelium in the Javan muntjac are similar to those found in neotropical cervids, small ruminants, and other domestic animals.

Spermatogenesis in house mouse in a Robertsonian polymorphism zone

Robertsonian (Rb) translocations can be important in speciation as a mechanism of postzygotic isolation between populations. Meiotic non-disjunction, gametogenic impairment, and association of impaired autosomal segments with sex chromosomes have been postulated as mechanisms responsible for reducing fertility in Rb mice. Quantitative histological studies needed to understand the role of Rb fusions in gametogenic impairment are scarce. Most research on Rb mice has analyzed meiotic non-disjunction of laboratory and wild-derived strains, which have complex or simple structural heterozygosity with large numbers of fusions. Using histological multilevel sampling, we examined spermatogenesis in mice from the Rb polymorphism area of Barcelona. We studied four chromosomal groups having: a) one Rb heterozygote fusion and 2n=39, b) one Rb heterozygote fusion and 2n=31, c) three Rb heterozygote fusions without monobrachial homology and with diploid number ranging from 2n=29 to 2n=37, and d) only Rb homozygote fusions with diploid number ranging from 2n=28 to 2n=30. Standard mice from the area surrounding the Rb zone were used as control. We analyzed morphological variables of the testes, relative frequency of stages in the seminiferous epithelium cycle, the 'round spermatids:primary spermatocytes' ratio, and other derived parameters. Our results reveal that structural homozygote mice and simple heterozygote mice having as few as one to three Rb fusions undergo greater germ cell death (GCD) than standard mice, suggesting that Rb fusions are related to increased GCD (in both the heterozygous and homozygous state) and may be the main cause of decreased gene flow between mice populations from this area.

Kinetics of spermatogenesis in the Mongolian gerbil (Meriones unguiculatus)

The Mongolian gerbil (Meriones unguiculatus) is a small rodent native to the arid regions of Mongolia and Northeastern China. The present study provides descriptions of both the cellular associations of the seminiferous-epithelium cycle and relative frequencies of stages in the gerbil. Based on the development of the acrosomic system and the nuclear morphology changes using the PAS-H staining technique, the transformation of spermatids into spermatozoa was divided into 15 steps. The first 12 steps were used to identify 12 stages or cellular associations and the other three steps were spread among the first six stages of the cycle of the seminiferous epithelium. The relative frequencies found for stages I through XII were: 13.15; 8.06; 8.98; 6.48; 5.37; 6.71; 7.36; 7.45; 7.27; 5.83; 11.53 and 11.81, respectively. Stage I had the highest frequency while stage V proved the lowest frequency among the XII stages. The pattern of spermatogenesis is similar to those of rodents used as laboratory animals. The present description is the first for this rodent and provides the foundation for a variety of future studies of the testis in this animal.

The spermatogenic cycle in the blue fox (Alopex lagopus): relative frequency and absolute duration of the different stages

The spermatogenic cycle of the blue fox was divided into eight distinct stages, based on an analysis of different cell associations of the seminiferous epithelium. The criteria used for classification of the stages were the type of spermatogonia, the occurrence of meiotic figures, and the shape and location of spermatids. The relative frequencies of the stages I to VIII were 25.7, 9.8, 8.7, 5.9, 13.8, 9.9, 10.6 and 15.5%, respectively. The duration of one cycle of the seminiferous epithelium was 12.0 +/- 0.2 days as determined from the progression of 5-bromo-2-deoxyuridine (BrdU)-labelled cells at various time intervals. The absolute duration of stages I to VIII was calculated to be 3.1, 1.2, 1.0, 0.6, 1.7, 1.2, 1.3 and 1.9 days, respectively. The estimated life span of primary spermatocytes was 19.2 days, of secondary spermatocytes less than 0.6 days, of spermatids with round nuclei 9.2 days and of spermatids with elongated nuclei 8.9 days.

The cycle of the seminiferous epithelium in the Australian Swamp buffalo

The relative frequencies of stages and substages of the Swamp buffalo seminiferous epithelium were determined using a morphological classification. Duration of one cycle of the seminiferous epithelium was determined from radiolabelling studies using tritiated thymidine. Mean (±SD) duration of the cyle of the seminiferous epithelium of five Swamp buffalo was 8.74 ± 0.18 d. Mean (±SEM) relative frequencies of stages and substages of the seminiferous epithelial cycle in ten bulls were Stage 1a, 7.27 ± 0.72; Stage 1b, 8.11 ± 0.85; Stage 1c, 8.54 ± 1.13; Stage 2a, 5.9 ± 0.79; Stage 2b, 7.49 ± 0.78; Stage 3a, 9.05 ± 0.66; Stage 3b, 9.69 ± 1.11; Stage 4a, 5.04 ± 0.44; Stage 4b, 4.8 ± 0.69; Stage 5, 1.86 ± 0.23; Stage 6, 8.81 ± 0.84; Stage 7, 10.64 ± 1.2; Stage 8a, 6.87 ± 0.96; and Stage 8b, 5.93 ± 0.72.

Reproduction in the Male Llama (<i>Lama glama</i>), a South American Camelid

The cycle of the seminiferous epithelium of the llama was divided into eight stages, using as criteria the shape and distribution of the germ cell nuclei, the location of the spermatids, the presence of meiotic figures and the release of spermatozoa from the tubular wall. Cell populations making up each stage are described. The relative frequencies of stages 1 through 8 were: 9.86, 12.46, 17.65, 14.12, 5.81, 8.09, 13.04 and 18.89%, respectively. In the seminiferous epithelium, spermatogonia of the A and B type are present and twelve spermiogenic steps can be recognized. Interstitial (Leydig) cells are packaged together forming large masses and elongated cords and share the intertubular space with one or two central great lymphatic vessels and few capillaries. Season male Leydig cells contain lipid droplets in their cytoplasm and show a marked immunoreactive testosterone reaction.

Cycle of the seminiferous epithelium and its duration in the zebu, Bos indicus

The cycle of the seminiferous epithelium was studied in Nelore zebu bulls 4–6 years old. The stages of the cycle were determined according to the shape and position of spermatid nuclei and the presence of meiotic divisions in cross-sections of seminiferous tubules. The relative frequencies of stages 1 to 8 were, respectively: 31.3 ± 0.5, 12.2 ± 0.7, 21.2 ± 0.5, 8.8 ± 0.6, 4.2 ± 0.4, 5.7 ± 0.6, 6.3 ± 0.5 and 10.3 ± 0.5. The duration of the cycle was estimated by autoradiography using tritiated thymidine injected directly into the testes. The mean duration of one cycle was estimated to be 14.0 ± 0.4 days.

Spermatogenesis in the dog.

AbstractThe cycle of the seminiferous epithelium of the dog was divided into eight stages, using as criteria the shape of the spermatid nucleus, the location of spermatids and spermatozoa in regard to the basement membrane, the presence of meiotic figures and the release of spermatozoa from the lumen of the tubule. Based upon these criteria, a modification of the eight‐stage system of classification of the cycle of the seminiferous epithelium was developed. Cell populations making up each stage are described. The relative frequencies of stages 1 through 8 were 21.9, 12.7, 2.8, 11.5, 8.3, 15.4, 13.3 and 14.0%, respectively. The duration of one cycle of the seminiferous epithelium was 13.6 days (SE ± 0.7), as determined from cells labeled by tritiated thymidine. The absolute durations of stages 1 through 8 were 3.0, 1.7, 0.4, 1.6, 1.1, 2.1, 1.8 and 1.9 days, respectively. The life span of primary spermatocytes was 20.9 days, of secondary spermatocytes 0.5 days, spermatids with round nuclei 10.5 days, spermatids with elongated nuclei up to the time they are released into the lumen, 10.6 days. Counts of the different types of spermatogenic cells in tubular cross sections revealed little or no germ cell degeneration during the two maturation divisions.