Water content within the testis is transferred across the seminiferous epithelium by Sertoli cells and served to transport sperm to the epididymis via the efferent duct. The water also plays an important role in the maintenance of liquid circumstance in the seminiferous tubule. Aquaporins (AQPs) are a family of integral membrane proteins that transport water, glycerol, urea and ions. In mammals, 13 AQPs isoforms have been identified, and they are expressed in a variety of tissues, including the kidney, the brain, the eye and the respiratory tract. In the testis, AQP0 and 8 have been identified in Sertoli cells, while AQP7, 8, 9 and11 have been identified in spermatogenic cells. These AQPs may be involved in testicular function such as spermatogenesis and spermiation. The present review focuses on the distribution and its possible function of AQPs in the testis.

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The development of hepatic sinusoids is only partially understood. This study investigated the development of hepatic sinusoids in order to clarify the formation process of sinusoidal endothelium by focusing on mouse tissue during a period of active liver hematopoiesis (E11-E16) using hematoxylin and eosin staining on paraffin-embedded liver sections, and toluidine blue staining on epoxy resinembedded semi-thin sections. Flat cells lining the luminal surface of hepatic sinusoids were identified as endothelial cells with CD-146 immunohistochemical staining.  We observed that developing sinusoids had partially naked walls that were not lined by flat cells, and from that hematopoietic cells and/or hepatic cells protruded into the sinusoidal lumen. In addition, CD-146 positive round cells scattering among hematopoietic cells and hepatic cells were observed. These observations suggest that hepatic sinusoids do not arise from the sprouting of intrahepatic capillary vessels but appear to be formed by CD-146 positive endothelial progenitor cells.

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Animals with a drunken gait were discovered during maintenance of the C57BL/6 polycystic kidney disease mouse (B6-cpk) strain. Their abnormal behavior included staggering and stumbling of the hind legs (wobble (wob)), and this was confirmed by observing sudden falls on their sides. These mice are bred by us and have been named B6-wob/takahashi (tentative (t)). The objective of this study was to evaluate the behavioral abnormalities of B6-wob/t and identify the causes. We performed behavioral analysis of B6-wob/t based on the open field activity, foot print, rotarod, beam walking, hanging and grip strength, and pole tests.  As a result, frequencies of reverse backward movement and pivoting in the open field activity were significantly (p<0.05∼0.001) increased in B6-wob/t (n=5) in comparison with B6(n=10). On the other hand, a significant reduction in the frequencies of rearing, preening and grooming (p<0.05∼0.001) was recognized. Duration of stay on the rod was significantly shorter (p<0.001) in B6 (600±0.0 sec.) in comparison with B6-wob/t (3.42±1.0 sec.) in the results of rotating rod tests. When all organs were pathologically investigated, cerebellar atrophy was macroscopically observed and the results suggested the central role of motion control as the major cause of the ataxic symptoms in B6-wob/t. This is the first report on B6-wob/t.

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In our previous study, we identified a novel intramuscular injection point at the intersection of the horizontal line from the anterior superior iliac spine and the perpendicular line from the middle portion of the trochanter major with the extended hip joint, and clarified that this point is as safe as the point of Clark for intramuscular injection. In the present study, we used 29 right buttocks of cadavers aged 59-100. We injected 1 mL gel into both the point of Clark and our novel intramuscular injection point to examine the relationship of the two points with nerves and blood vessels by investigating whether they were present in the gel. Ultrasound tomography was used to measure the thickness of the subcutaneous tissue and the gluteal muscle at both points. The incidence of accidental insertion to nerves or blood vessels at the two sites was almost the same as we experienced in our previous study. This indicates that our novel intramuscular injection point provides an appropriate site for intramuscular injection to the gluteal muscle. The injected gel made a mass between the gluteus medius and minimus muscles, suggesting the possibility that hematomas could be formed with negative effects on nerves and blood vessels. Since the thickness of subcutaneous tissue ranged from 1.2 to 2.6 cm at both points, we consider that a depth of 3 cm at a right angle to the skin is appropriate for both the point of Clark and our novel intramuscular injection point. However, assessment of the thickness of fatty tissue with confirmation of the position of blood vessels by ultrasound tomography is recommended for safe intramuscular injection.

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In our previous study, we identified a novel intramuscular injection point located at the intersection of the horizontal line from the anterior superior iliac spine and the perpendicular line from the middle portion of the trochanter major with the extended hip joint, and clarified that this site is as safe as the point of Clark for intramuscular injection. The aims of the present study were to determine whether intramuscular injection at our novel point is safe during flexion of the hip joint, and to determine the optimal depth of needle insertion for use in clinical settings. We determined four sites as injection points in the right buttocks of women aged 21-27 at four sites: Clark's point, our novel intramuscular point with extended hip joint (angle 0°), our novel point with hip joint flexed 45° and our novel point with hip joint flexed 90°. After measuring the distances between the point of Clark and each novel intramuscular injection point, we used ultrasound to measure the thickness of subcutaneous fat and gluteal muscle, and measured blood flow. We found that our novel intramuscular injection point was near the point of Clark during hip joint flexion, and the thickness of the subcutaneous fat and the gluteal muscle did not show significant differences. Our results suggested that this novel point is safe for intramuscular injection. We furthermore examined the optimal depth for insertion of the needle, considering the thickness of the subcutaneous fat, and found that inserting the needle 3 cm perpendicular to the skin is ideal for safe intramuscular injection, because it helps prevent damage to the nerves and blood vessels.

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