Integrins are not involved in the process of human sperm-oolemmal fusion

BACKGROUND: We investigated whether integrins are required forthe human sperm–oocyte binding and fusion processes. METHODS:The expression of several integrin subunits at the human oocyteplasma membrane was investigated using immunofluorescence microscopy,and the functional role of integrins expressed at the humanoocyte surface in sperm–oocyte interaction was studiedusing a zona-free human oocyte binding and fusion assay. A totalof 144 unfertilized oocytes were stained with anti-integrinantibodies and 147 zona-free unfertilized oocytes were inseminatedin the presence of various anti-integrin antibodies that wereexpressed in oocyte plasma membrane. RESULTS: The antibodiesof six integrin subunits (₂, ₃, ₅, ₆, _V, _M) and six integrinsubunits (₁, ₂, ₃, ₄, ₅, ₆) were bound to the surface of fixedunfertilized oocytes. In contrast, the presence of ₁ and ₄ subunitscould not be verified. The human sperm–oocyte bindingwas only partially inhibited by blocking antibodies of ₂, ₃,₅, ₆, _V, _M, ₁, ₂ and ₃ with a maximum of 55% inhibition, butantibodies of ₄, ₅ and ₆ showed no effect on sperm–oolemmalbinding. A similar reduction of the number of fused sperm wasobserved. However, the ratio of fused sperm to total sperm (boundand fused) was not impaired by all integrin antibodies, suggestingthat integrins had no role in the sperm–oolemmal fusionprocess. CONCLUSIONS: These results suggest that one of thebinding mechanisms can be inhibited by integrin antibodies butthat this mechanism does not play an essential role in the humansperm–oolemmal binding and fusion processes. The othermechanisms, insensitive to integrins, may involve both bindingand fusion processes in human oocytes.     

Expression of the TGF-β–ALK-1 Pathway in Dura and the Outer Membrane of Chronic Subdural Hematomas

Neovascularization of the outer membrane plays a critical role in the development and enlargement of chronic subdural hematomas (CSHs) and vascular endothelial growth factor (VEGF) may promote their progression. However, the precise mechanisms remain to be determined. We focused on the signaling pathway upstream of VEGF, transforming growth factor β (TGF-β), and activin receptor-like kinase 1 (ALK-1) to identify the mechanisms underlying the neovascularization of the outer membrane of CSH. Retrospective comparative study was conducted on 15 consecutive patients diagnosed as CSH with burr-hole drainage. Dura and the outer membrane were collected. We immunohistochemically examined the expression of VEGF, integrin-α, TGF-β, and ALK-1 on the outer membrane and dura of CSH and compared our findings with control samples and the signal intensity of hematomas on computed tomography (CT) scans. VEGF and integrin-α expression was markedly up-regulated in both the dura and outer membrane of CSH, the expression of TGF-β and ALK-1 in the dura was slightly increased in the dura and markedly up-regulated in the outer membrane. There was no significant correlation between their expression and CT density. Here we first report the expression of TGF-β and ALK-1 in the outer membrane and dura mater of CSH. We suggest that the TGF-β–ALK-1 pathway and VEGF affect neovascularization and the progression of CSH.     

A case of liver abscess co-infected with Desulfovibrio desulfuricans and Escherichia coli and review of the literature

A 73-year-old woman was admitted with consciousness disturbance following a fever. Abdominal computed tomography revealed a large liver abscess with which the presence of Desulfovibrio desulfuricans and Escherichia coli was confirmed by thorough blood and abscess content culture. Empiric meropenem treatment was switched to cefoperazone/sulbactam, followed by ampicillin/sulbactam based on susceptibility testing. Desulfovibrio desulfuricans is a common bacterium that rarely causes liver abscess and may be overlooked during co-infection due to overgrowth of the accompanying bacteria. Clinicians should bear Desulfovibrio desulfuricans in mind and select the appropriate antibiotics according to susceptibility testing when anaerobic bacteria are detected in a liver abscess.     

Association analysis of toll-like receptor 4 polymorphisms in Japanese primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is characterized by portal inflammation and immune-mediated destruction of intrahepatic bile ducts that often result in liver failure. Toll-like receptor (TLR) 4 recognizes lipopolysaccharides of Gram-negative bacteria. Infectious agents have been suspected to play a crucial role in PBC pathogenesis since TLR4 expression was found in bile duct epithelial cells and periportal hepatocytes in liver tissues of PBC. To assess the potential contribution of TLR4 SNPs to the development of this disease, we genotyped five SNPs in TLR4 in 261 PBC patients and 359 controls using a TaqMan assay. No significant positive associations with either PBC susceptibility or progression were uncovered. These results indicate that TLR4 polymorphisms do not play a prominent role in the development of PBC in Japanese patients.     

A case presenting brain abscess with multiple infectious aneurysms

We report a case presenting a brain abscess with multiple infectious aneurysms. A 59-year-old man was transferred to our hospital suffering from left hemiparesis. MRI demonstrated a huge mass in the right frontal lobe with marked brain edema in the surrounding area. Diffusion-weighted image revealed heterogenous intensity, which is not typical in cases of brain abscess. Surgical removal was planned, and preoperative angiography was performed. Angiography demonstrated aneurysms at the distal branch of both the right middle cerebral artery and the anterior cerebral artery. These aneurysms were surgically resected, and the abscess was totally removed. Postoperative course was uneventful. Left hemiparasis was resolved, and there was no ischemic lesion seen on postoperative MRI. In the treatment of brain abscess, stereotactic aspiration has recently been preferred to removal by craniotomy. We conclude that cerebral angiography might be necessary to evaluate cerebrovascular complications including infectious aneurysms, in cases presenting atypical findings in neuroimaging study.