Objective To evaluate the semen quality and sperm morphology in the patients with different grades of varicocele. Methods Semen from 121 patients with varicocele which were divided into three groups, gradel, grade Ⅱ and grade Ⅲ, were studied and those of 23 normal male were taken as the control. Semen analysis was performed with the methods described in the WHO manual and sperm morphology was evaluated by WHO cri-teria. Results A significant reduction of semen quality and sperm morphology and an increase of small oval head, tapering head and amorphous head sperm were found in patients with different grades of varicocele compa-ring with those of the control. There was no difference in routine analysis between different groups. A reducetion of normal morphology percentage in grade Ⅲ were found comparing with grade Ⅱ (P<0.01). An increase of a-morphous head sperm in grade Ⅲ was found comparing with that of sperm in grade Ⅱ (P <0.01). Canclusions The routine semen analysis can not distinguish seminal damage between different grades of varicocele, but the sperm morphology can reflect the sperm state. Therefore, the patients with varicocele should not only get routine semen analysis but also check the sperm morphology.

Background: and Purpose We investigated the causal relationships between the gut microbiota (GM), stroke, and potential metabolite mediators using Mendelian randomization (MR). Methods: We leveraged the summary statistics of GM (n=18,340 in the MiBioGen consortium), blood metabolites (n=115,078 in the UK Biobank), and stroke (cases n=60,176 and controls n=1,310,725 in the Global Biobank Meta-Analysis Initiative) from the largest genome-wide association studies to date. We performed bidirectional MR analyses to explore the causal relationships between the GM and stroke, and two mediation analyses, two-step MR and multivariable MR, to discover potential mediating metabolites. Results: Ten taxa were causally associated with stroke, and stroke led to changes in 27 taxa. In the two-step MR, Bifidobacteriales order, Bifidobacteriaceae family, Desulfovibrio genus, apolipoprotein A1 (ApoA1), phospholipids in high-density lipoprotein (HDL_PL), and the ratio of apolipoprotein B to ApoA1 (ApoB/ApoA1) were causally associated with stroke (all P<0.044). The causal associations between Bifidobacteriales order, Bifidobacteriaceae family and stroke were validated using the weighted median method in an independent cohort. The three GM taxa were all positively associated with ApoA1 and HDL_PL, whereas Desulfovibrio genus was negatively associated with ApoB/ApoA1 (all P<0.010). Additionally, the causal associations between the three GM taxa and ApoA1 remained significant after correcting for the false discovery rate (all q-values <0.027). Multivariable MR showed that the associations between Bifidobacteriales order, Bifidobacteriaceae family and stroke were mediated by ApoA1 and HDL_PL, each accounting for 6.5% (P=0.028) and 4.6% (P=0.033); the association between Desulfovibrio genus and stroke was mediated by ApoA1, HDL_PL, and ApoB/ApoA1, with mediated proportions of 7.6% (P=0.019), 4.2% (P=0.035), and 9.1% (P=0.013), respectively. Conclusion The current MR study provides evidence supporting the causal relationships between several specific GM taxa and stroke and potential mediating metabolites.