Novel stage classification of human spermatogenesis based on acrosome development.

International audienceTo date, in the human seminiferous epithelium, only six associations of cell types have been distinguished, subdividing the epithelial cycle into six stages of very different duration. This hampers comparisons between studies on human and laboratory animals in which the cycle is usually subdivided into 12 stages. We now propose a new stage classification on basis of acrosomal development made visible by immunohistochemistry (IHC) for (pro)acrosin. IHC for acrosin gives results that are comparable to periodic acid Schiff staining. In the human too, we now distinguish 12 stages that differ from each other in duration by a factor of two at most. B spermatogonia are first apparent in stage I, preleptotene spermatocytes are formed in stage V, leptonema starts in stage VII, and spermiation takes place at the end of stage VI. A similar timing was previously observed in several monkeys. Stage identification by way of IHC for acrosin appeared possible for tissue fixed in formalin, Bouin fixative, diluted Bouin fixative, Cleland fluid, and modified Davidson fixative, indicating a wide applicability. In addition, it is also possible to distinguish the 12 stages in glutaraldehyde/osmium-tetroxide fixed/plastic embedded testis material without IHC for acrosin. The new stage classification will greatly facilitate research on human spermatogenesis and enable a much better comparison with results from work on experimental animals than hitherto possible. In addition, it will enable a highly focused approach to evaluate spermatogenic impairments, such as germ cell maturation arrests or defects, and to study details of germ cell differentiation

Liver harvesting surgical technique for the treatment of retro-hepatic caval thrombosis concomitant to renal cell carcinoma: perioperative and long-term results in 15 patients without mortality.

Objective: Radical surgical treatment improves the prognosis of patients affected by Inferior Vena Cava (IVC) thrombosis concomitant to renal carcinoma. However, thrombus extension above the infrahepatic IVC represents a major technical topic for surgeons because of the possible occurrence of uncontrollable haemorrhages and tumor fragmentation. We report the results of an innovative surgical approach to caval thrombosis including the isolation of the IVC from the liver as routinely performed during liver harvesting. In the presence of retro-hepatic IVC thrombosis, this technique improves vascular control and allows to perform a large cavotomy with an en-bloc removal of the thrombus and the tumor. Methods: From January 1995 through June 2003, 15 patients with renal cancer and caval thrombosis were treated at our Institution. Four, ten and one patients were respectively affected by an infrahepatic (Level I), retro-hepatic (Level II) and atrial (Level III) IVC thrombosis. Results: All patients underwent radical surgical treatment. In presence of Level II caval thrombosis, the patients underwent the above reported surgical technique. Perioperative mortality was absent; major morbidity occurred in one patient (6.7%). The thrombus was radically removed in all cases. After a mean follow-up of 53.9 months (5–100 months) all patients but one are still alive. One patient died 9 months after surgery with multiple bilateral pulmonary metastases. Conclusions: Isolation of the retro-hepatic IVC is a safe and effective manoeuvre to signi?cantly reduce perioperative mortality and morbidity in patients affected by Level II caval thrombosis concomitant to renal carcinoma

Female gender and overestimation of glomerular filtration rate: independent predictors of acute kidney injury after liver transplantation

Acute kidney injury (AKI) in liver transplant (LT) setting is a recognized complication and is related to increased morbidity and mortality. Pre-LT renal function is difficult to estimate, in particular for the female gender. The aim of the study was to evaluate the incidence of post-LT AKI, its relationship with survival, and related risk factors. In a single-center retrospective study of consecutive LT patients (2008 - 2015), we assessed patient characteristics and intra-LT events, and post-operative data were collected. The occurrence of AKI post-LT was also evaluated (KDIGO guidelines). Data of 145 LT patients were analyzed. 45 (31.0%) patients showed an overestimation of glomerular filtration rate (over-GFR), defined as GFR > 120 mL/min/1.73m2; 83 patients (57.2%) developed post-LT AKI. The patients (n = 145) were divided into two groups: 123 (84.8%) patients with no-AKI & AKI stage 1 and 22 (15.2%) patients with AKI stages 2 and 3. Patients with AKI stages 2 and 3 were characterized by a significantly decreased 5-year survival (p < 0.001). On the multivariable analysis, female gender and over-GFR were significantly predictive for development of AKI stages 2 and 3. Female gender has already been reported as a discriminant factor for LT candidates. Altered estimation of renal function also needs to be considered in this setting, as this could mask the presence of an unknown compromised renal function.