Alendronate does not prevent long bone fragility in an inactive rat model

The lack of estrogen and inactivity are both important in the pathogenesis of osteoporosis in elderly women, and there have been no appropriate rodent studies to examine the effects of common bisphosphonates on these two components separately. We compared the efficacy of alendronate (ALN) on the long bones of aged female rats, which were sedentary, estrogen deficient, or both. The rats were either forced to remain in a sitting position or allowed to walk in standard cages with or without ALN administration. The 8-week experimental period began 5 weeks after ovariectomy or sham surgery. Parameters of the hindlimb bones were determined by a three-point bending test, peripheral quantitative computed tomography, microfocus computed tomography, confocal laser Raman microspectroscopy, and dynamic histomorphometry. Regardless of ovariectomy, ALN was ineffective against the deterioration of breaking stress caused by sitting even though the trabecular bone mineral density was significantly higher in the sitting–ALN groups. Toughness was significantly deficient in the ovariectomy sitting–ALN group. This was in agreement with the bone geometry with a greater marrow space. Sitting also increased the mineral-to-matrix ratio and the carbonate-to-phosphate ratio, both indicative of aged bone. A greater loss of proteinaceous amide intensity compared with mineral intensity resulted in an increased mineral-to-matrix ratio in the presence of ALN. Sitting resulted in deficits in the quality and the geometry of cortical bone, resulting in fragility. The use of bisphosphonates, such as ALN, may provide a therapy best suited for osteoporotic individuals whose daily activity is not limited.     

Retro-transduction by virus pseudotyped with glycoprotein of vesicular stomatitis virus

A virus pseudotyped with glycoprotein of vesicular stomatitis virus (VSV-G) can enter various cell types at a relatively high titer. We observed that the amount of viral antigen from VSV-G pseudotyped human immunodeficiency virus type 1 (HIV-1) producing cells was much higher than that from their non-pseudotyped counterparts. This enhanced viral antigen production was not observed when we used HIV-1 pol mutant, viral enzyme inhibitors, HIV Env protein, or VSV-G fusion defective mutants. The transfection experiment using GFP-expressing virus showed time-dependent expansion of GFP-positive cells and viral DNA integration. These results suggested that the increase in viral antigen yield was caused by the release of a progeny virus following retro-transduction by the pseudotyped virus of the cells within the transfected cell culture. The infectivity as well as the amount of VSV-G on virus particles per unit of viral antigen was significantly different before and after the onset of the yield enhancement. This suggests that results of infection assays of the virus pseudotyped with VSV-G may be affected by the occurrence of such enhancement. This means that, while pseudotyping with VSV-G is a simple and effective method, this procedure should be carefully considered when the virus is produced for infectivity assays.     

Different patterns of cerebellar abnormality and hypomyelination between POLR3A and POLR3B mutations

Background

Mutations of POLR3A and POLR3B have been reported to cause several allelic hypomyelinating disorders, including hypomyelination with hypogonadotropic hypogonadism and hypodontia (4H syndrome). Patients and methods: To clarify the difference in MRI between the two genotypes, we reviewed MRI in three patients with POLR3B mutations, and three with POLR3A mutations. Results: Though small cerebellar hemispheres and vermis are common MRI findings with both types of mutations, MRI in patients with POLR3B mutations revealed smaller cerebellar structures, especially vermis, than those in POLR3A mutations. MRI also showed milder hypomyelination in patients with POLR3B mutations than those with POLR3A mutations, which might explain milder clinical manifestations. Conclusions: MRI findings are distinct between patients with POLR3A and 3B mutations, and can provide important clues for the diagnosis, as these patients sometimes have no clinical symptoms suggesting 4H syndrome.     

Comparing the Efficacy of a Microperforated Titanium Membrane for Guided Bone Regeneration with an Existing Mesh Retainer in Dog Mandibles

Acute-type lateral ridge defects (25 mm × 6 mm × 5 mm) were bilaterally created in the mandibles of four dogs (two defects per animal). The defects were reconstructed with particulate autologous bone and covered with a microperforated titanium membrane (Ti-honeycomb membrane, TiHM) or an existing conventional titanium mesh as control. The samples were dissected after 16 weeks postoperatively and processed for radiographic, histologic, and histomorphometric analyses. Regenerated tissue and bone volume were significantly larger in the TiHM group than in the control group (p = 0.05; p = 0.049). In contrast, bone mineral density was similar between the two groups. Histomorphometric analysis revealed that the regenerated bone area and calcific osseous area were larger in the TiHM group than in the control group; however, the differences were not significant. The efficacy of TiHM was generally satisfactory with the potential to become a standard tool for the GBR procedure; however, early membrane exposure will be a major problem to overcome.     

Structure-Guided Design of Novel l-Cysteine Derivatives as Potent KSP Inhibitors

l-cysteine derivatives as selective KSP inhibitors. Here, we report further optimizations using docking modeling in the L5 allosteric binding site, which led to the discovery of several high affinity derivatives with two fused phenyl rings in the trityl group giving low nanomolar range KSP ATPase inhibition. The representative derivatives potently inhibited cell growth of HCT116 cells in correlation with KSP inhibitory activities and significantly suppressed tumor growth in the xenograft model in vivo.     

Pure laparoscopic pancreas parenchymal dissection using CUSA for distal pancreatectomy

Although stapler dissection and closure is commonly used for laparoscopic distal pancreatectomy (LDP), it is risky in patients with thick pancreatic parenchyma or titanium allergy. We performed laparoscopic pancreatic parenchymal dissection with cavitron ultrasonic surgical aspirator (CUSA) successfully in a patient with titanium allergy. Slinging the pancreas with nylon tape delineates the surgical plane. Pancreatic parenchyma was transected by CUSA in an almost bloodless field. Pancreatic duct branches and vessels were adequately exposed and dissected with a vessel sealing system. The main pancreatic duct was closed with Hem-O-lock. CUSA is an alternative to stapler dissection during LDP in select patients.     

Hepatitis-associated aplastic anemia preceded by a hemophagocytic syndrome-like state

A 21-year-old man was admitted to our hospital for acute hepatitis of unknown cause. His liver function improved with rest, but worsened 2 months later. He developed a high fever and pancytopenia. The serum level of cytokines including TNF-alpha, IFN-gamma, IL-6, and M-CSF was elevated, and hemophagocytes were seen in bone marrow. These findings suggested a hemophagocytic syndrome-like state. With prednisolone, gamma-globulin, and G-CSF, the high fever disappeared and the patient's liver function gradually recovered. However, the severe pancytopenia persisted. The bone marrow became acellular with a small number of hemophagocytes, and hepatitis-associated aplastic anemia was diagnosed. After immunosuppressive therapy with ATG, CyA and G-CSF was started, and the patient showed hematopoietic reconstitution. The bone marrow CD4+/CD8+ lymphocyte ratio recovered to within the normal range, and the serum cytokines including TNF-alpha and IFN-gamma decreased. The increase in serum cytokines, particularly TNF-alpha and INF-gamma, as well as the presence of activated T cells associated with the preceding hemophagocytic syndrome-like state may have predisposed this patient to aplastic anemia.