Better knowledge of the risk factors associated with the appearance of hepatocellular carcinoma (HCC) could improve the efficacy of surveillance programs. A total of 463 patients aged 40 to 65 years with liver cirrhosis in Child-Pugh class A or B were included in a program of early diagnosis. The predictive value of different risk factors was evaluated using the Kaplan-Meier method and Cox regression model. Thirty-eight patients developed HCC. In the multivariate analysis, 4 variables showed an independent predictive value for the development of HCC: age 55 years or older, antibody to hepatitis C virus (anti-HCV) positivity, prothrombin activity 75% or less, and platelet count less than 75 ؋ 10 3 /mm 3 . According to the contribution of each of these factors to the final model, a score ranging between 0 and 4.71 points was constructed to allow the division of patients into 2 different risk groups. The low-risk group included those with a score of 2.33 points or less (n ؍ 270; 4 with HCC; cumulative incidence of HCC at 4 years, 2.3%), and the high-risk group included those with a score greater than 2.33 (n ؍ 193; 34 with HCC; cumulative incidence of HCC at 4 years, 30.1%) (P ؍ .0001). In conclusion, a simple score made up of 4 clinical and biological variables allowed us to distinguish 2 groups of cirrhotic patients at high and low risk for the development of HCC. We believe this score can be useful in establishing a subset of cirrhotic patients in whom a surveillance program for early detection of HCC could be unjustified.
Postcopulatory sexual selection through sperm competition may be an important evolutionary force affecting many reproductive traits, including sperm morphometrics. Environmental factors such as pollutants, pesticides, and climate change may affect different sperm traits, and thus reproduction, in sensitive bird species. Many sperm-handling processes used in assisted reproductive techniques may also affect the size of sperm cells. The accurately measured dimensions of sperm cell structures (especially the head) can thus be used as indicators of environmental influences, in improving our understanding of reproductive and evolutionary strategies, and for optimizing assisted reproductive techniques (e.g., sperm cryopreservation) for use with birds. Computer-assisted sperm morphometry analysis (CASA-Morph) provides an accurate and reliable method for assessing sperm morphometry, reducing the problem of subjectivity associated with human visual assessment. Computerized systems have been standardized for use with semen from different mammalian species. Avian spermatozoa, however, are filiform, limiting their analysis with such systems, which were developed to examine the approximately spherical heads of mammalian sperm cells. To help overcome this, the standardization of staining techniques to be used in computer-assessed light microscopical methods is a priority. The present review discusses these points and describes the sperm morphometric characteristics of several wild and domestic bird species.
The aim of this study was to examine ovine sperm cryoresistance during the rutting season (RS) and its association with sperm head area and seminiferous epithelium proliferation. Small ruminants show fluctuating testosterone levels throughout the year, which could interfere with spermatogenesis and sperm cryopreservation. Ejaculates, testicular biopsies and blood were collected during the middle and at the end of the RS (Middle-RS vs End-RS) during periods of high and low testosterone levels in Merino and Mouflon rams. Fresh and frozen–thawed sperm quality, sperm morphometry, seminiferous tubule morphometry and testicular proliferation markers (proliferating cell nuclear antigen, proliferation marker protein Ki-67 and transcription factor GATA-4) were evaluated. Post-thaw sperm viability was higher in the End-RS group in both Merino (69.9±8.2 vs 41.6±7.3%; P=0.020) and Mouflon rams (40.9±3.3 vs 24.2±5.0%; P=0.008). Mouflons had larger sperm head area at the End-RS (38.3±0.2 vs 34.3±0.1µm2; P=0.029), whereas there was no difference between Merino groups (35.7±0.5 vs 34.8±1.0µm2). Seminiferous tubule morphometry and proliferation markers showed higher levels of germinal epithelium proliferation in the Middle-RS of both species. In conclusion, sperm freezability is affected during the RS in domestic and wild rams, which could be correlated with changes that occur during spermatogenesis, since there is an effect of season on cell proliferation in the testis.
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