Human papillomaviruses (HPVs) represent a family of diverse DNA viruses consisting of more than 100 types and have been extensively studied as an etiological factor in benign and malignant tumors. In malignant epithelial lesions, the mechanism by which two E6 and E7 proteins of the high risk HPV types, HPV 16 and 18 interact with cellular factors in deregulating the normal growth of the cells, has been well described by many authors. The E6 and E7 proteins are consistently expressed in HPV-associated malignant tumor and E6 binding to the p53 gene mediated by the E6-associated protein ligase turned out to be important. In contrast important function of E7 was demonstrated by its binding to pRb and Rb-related proteins. The bindings under phosphorylation of these proteins was degradated by ubiquination and transcription factors of the E2F regulated cell proliferation. Overall HPV 16 DNA is able to induced modifications in the host cells and immortalizing epithelial cells by stimulating human telomerase reverse transcriptase (hTERT) protein. High risk E6 proteins directly interacts with c-myc and c-myc/E6 complex activates hTERT protein expression.
The various methods for detection or cloning of HPV DNA are summarized in this manuscript. PCR method has been become an established technique for detecting a large number of HPV DNAs. In particular PCR-RFLP is a simple and useful method for identifying the specific HPV types. However many modifications of the methods have been developed. Recently clinical trials are being conducted to test the preventive efficacy of HPV vaccines, directed against HPV 16 and 18 in Japan. In the future the therapeutic efficacy of HPV vaccines are required to prevent cervical cancer and other HPV associated cutaneous carcinomas.

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The aim of this study was to investigate maternal and neonatal outcomes in dichorionic twin pregnancies in older primiparae (nulliparous women older than 35 years) compared with those in younger primiparae. This was a retrospective study of dichorionic twin pregnancies managed at Japanese Red Cross Katsushika Maternity Hospital from 2002 through 2006. Nulliparous women 35 years and older at delivery (n=60) were compared with nulliparous women between the aged 20 to 34 years at delivery (n=181). The women 35 or older were more likely to have used assisted reproductive technology. There were no measurable differences in obstetric outcomes such as preeclampsia, premature delivery, low birth weight and neonatal asphyxia between the two groups. Advanced maternal age does not seem to affect obstetric outcomes in nulliparous dichorionic twin pregnancies.

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The use of stem cells is promising for future cell-based therapies such as tissue regeneration and engineering. Although embryonic stem cells are theoretically beneficial, there are several potential limitations, such as cell regulations and ethical considerations. Mesenchymal stem cells isolated from bone marrow stroma have been shown to possess adipogenic, osteogenic, chondrogenic, myogenic, and neurogenic potential in vitro and in vivo. However, bone marrow procurement is so painful for donors that general anesthesia is often required. Moreover, the yield of harvested cells is low. A similar pluripotent cell population was isolated from human adipose tissue in 2001 and termed adipose-derived stem cells (ASCs). Since then, our laboratory has investigated the versatility of ASCs for regenerative medicine both in vitro and in vivo. We found that (1) ASCs were successfully induced to differentiate into neurogenic, angiogenic and cardiomyogenic lineages, as well as adipogenic, chondrogenic, osteogenic and myogenic lineages in vitro and (2) mature tissue, including fat, bone, cartilage, bone marrow, granulation tissue, and periodontal tissue, was regenerated in a murine model in vivo. Because human adipose tissue is plentiful, and easily harvested in large quantity under the local anesthesia with less discomfort for patients, it may be an alternative stem cell source for mesenchymal tissue regeneration and engineering. In this paper, our research about ASCs and future clinical applications are described.

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An 80-year-old man died of rupture of the thoracic aorta 3 months after surgery for abdominal aortic aneurysm. Autopsy revealed that multiple penetrating atherosclerotic ulcers with intramural hematoma had resulted in psudoaneurysm of the abdominal aorta and dissection of the thoracic aorta. Differentiation from common aortic aneurysm or classic aortic dissection is important because pseudoaneurysm and aortic dissection related to penetrating atherosclerotic ulcer have a higher risk of rupture.

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To understand neural mechanisms of reproductive physiology, we have generated promoter transgenic rats for gonadotropin-releasing hormone (GnRH) neurons. Using these rats we have analyzed ion channels expressed in rat GnRH neurons by means of patch clamp experiments and reverse transcriptase-polymerase chain reaction. The study revealed that rat GnRH neurons exhibit voltage-gated Na⁺, K⁺ and Ca²⁺ currents. There are delayed rectifier K⁺ currents, large conductance voltage- and Ca²⁺ -activated K⁺ currents (BK currents carried through BK channels) and Ca²⁺ -activated K⁺ currents (slow afterhyperpolarization currents carried through SK channels). Ca²⁺ currents are carried through five different Ca²⁺ channels, namely L-, N-, P/Q-, R- and T-types. Activation of these ion channels determines excitability of GnRH neurons and their firing pattern of action potentials.

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Phacoemulsification and aspiration (PEA) has become the most popular type of cataract surgery. The safety of cataract surgery has been dramatically improved due to the development of surgical techniques and associated instruments. However, corneal endothelial damage still represents a serious complication, as excessive damage can lead to irreversible bullous keratopathy. Collision of lens fragments to corneal endothelium by turbulent flow causes physical breakdown of the endothelial cells. We report a case in which corneal endothelial damage occurred by the collision of lens fragments during phacoemulsification and aspiration. The outcome prompted us to perform safer operations with new surgical instruments.

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