アフリカ都市貧困地区における生物医療の展開と住民の治療ネットワーク形成に関する研究 : ナイジェリア・ラゴス州エグンのマラリア対処を事例に

学位の種別: 課程博士審査委員会委員 : （主査）東京大学教授 遠藤 貢, 東京大学教授 市野川 容孝, 東京大学准教授 関谷 雄一, 東京大学教授 森山 工, 関西外国語大学准教授 近藤 英俊University of Tokyo(東京大学

Scrutiny on Physical Properties of Sawdust From Tropical Commercial Wood Species: Effects of Different Mills and Sawdust's Particle Size

Physical properties of sawdust (i.e. particle size distribution, particle density, porosity, and water retention) from five tropical commercial wood species (Shorealeprosula, Dryobalanops lanceolata, Dipterocarpus cornutus, Shorea laevis, and Eusideroxylon zwageri) as prepared in various mill types (i.e. handsaw, sawmill, and milling ) were analyzed. This study aims to look into the relationship and interconnected between the use of different mill types, density of wood species origin and physical properties of the resulting sawdust. Generally, different mill types produced sawdust with different particle size distributions. The use of a handsaw produced a higher proportion of oversized particles (OS) and coarser particle size (CPS) than that of sawmill and milling , while also commonly producing the lowest proportion of fine particle size (FPS). For each wood species, the proportion of OS was lower than that of CPS and FPS. In addition, particle density and water retention produced by handsaw in CPS as well as FPS was the smallest, followed in an increasing order sawmill and milling. Porosity of CPS and FPS was the highest in handsaw-cut sawdust, followed in a decreasing order sawmill and milling cut sawdust. This study showed that the different mill types and particle size influenced the physical properties of sawdust. Further, analysis of influential factors on porosity and water retention using General Linear Model revealed that particle density inflicted a strong influence on porosity, as did particle size on water retention

Serum Anti-BPAG1 Auto-Antibody Is a Novel Marker for Human Melanoma

Malignant melanoma is one of the most aggressive types of tumor. Because malignant melanoma is difficult to treat once it has metastasized, early detection and treatment are essential. The search for reliable biomarkers of early-stage melanoma, therefore, has received much attention. By using a novel method of screening tumor antigens and their auto-antibodies, we identified bullous pemphigoid antigen 1 (BPAG1) as a melanoma antigen recognized by its auto-antibody. BPAG1 is an auto-antigen in the skin disease bullous pemphigoid (BP) and anti-BPAG1 auto-antibodies are detectable in sera from BP patients and are used for BP diagnosis. However, BPAG1 has been viewed as predominantly a keratinocyte-associated protein and a relationship between BPAG1 expression and melanoma has not been previously reported. In the present study, we show that bpag1 is expressed in the mouse F10 melanoma cell line in vitro and F10 melanoma tumors in vivo and that BPAG1 is expressed in human melanoma cell lines (A375 and G361) and normal human melanocytes. Moreover, the levels of anti-BPAG1 auto-antibodies in the sera of melanoma patients were significantly higher than in the sera of healthy volunteers (p<0.01). Furthermore, anti-BPAG1 auto-antibodies were detected in melanoma patients at both early and advanced stages of disease. Here, we report anti-BPAG1 auto-antibodies as a promising marker for the diagnosis of melanoma, and we discuss the significance of the detection of such auto-antibodies in cancer biology and patients

Biofilm deficiency in polysaccharide intercellular adhesin-negative variants of staphylococcus epidermidis selected by subminimal inhibitory concentrations of gentamicin

Staphylococcus epidermidis is a cause of orthopedic device-related infection, and to treat such infection, biofilms should be controlled. Polysaccharide intercellular adhesin (PIA) is associated with the biofilm-forming ability of staphylococcal strains. PIA in biofilm-positive staphylococcal strains can be detected by the Congo red agar (CRA) method. In this study, we used the CRA method to examine the effects of subminimal inhibitory concentrations (sub-MICs) of 11 antibacterial agents on PIA production by S. epidermidis. We found that the PIA-negative variants were selected only by sub- MICs of gentamicin (GM). This PIA-negative phenotype was maintained over several generations in the absence of GM. Such selection occurred in six of eight clinical isolates, as well as in the biofilm-positive control strain. No such selection occurred with aminoglycoside antibiotics except for GM. Most of the PIA-negative variants that were selected by GM showed a markedly lower biofilm-forming ability on stainless steel washers than their untreated parent strains. In conclusion, variants with lower biofilmforming ability may be selected by a sub-MIC of GM. Investigation of the reason why variants with reduced biofilm-forming ability can be selected in the presence of sub-MICs of GM may contribute to strategies against biofilm-related infections

Fast and Slow Oscillation Electrooculography in Harada Disease

We assessed clinical utility of fast and slow oscillations (FO and SO) of the electrooculogram (EOG) in Harada disease. In 12 eyes of 4 female and 2 male subject patients aged 18 to 77 years (average: 41.8 years), FO and SO were recorded using an automated electrooculograph, the Nidek EOG-2, in the acute period before treatment and in the remission period under corticosteroid therapy. FO parameters, namely the RfFO [the average ratio in percentage of the maximum amplitude in the dark period (AD)/the minimum amplitude in the light period (AL) during FO measurement] and the dfFO (the average difference in ?V between AD and AL) were evaluated. The L/DSO (the light peak/dark trough ratio of the SO) was calculated as an SO parameter. The RfFO, dfFO and L/DSO showed low values in 7 (58.3%), 10 (83.3%) and 8 (66.7%) out of all 12 eyes in the acute period, respectively. In the remission period, values in the normal range were obtained in 12 (100%), 11 (91.7%) and 8 (66.7%) out of 12 eyes in the RfFO, dfFO and L/DSO, respectively. In mutual relation to each RfFO, dfFO and L/DSO in the acute and remission periods, all 12 eyes showed recovery values both in the RfFO and dfFO in the remission stage after systemic administration of corticosteroids, but 4 out of 12 eyes (33.3%) showed no recovery in the L/DSO. The FO may therefore well reflect the affected or ameliorated conditions in the outer layers of the retina and the choroid in Harada disease, in contrast to the SO. However, further observations are requested in more Harada disease patients

Clinical Evaluation of a Three-Dimensional Ultrasonography System in the Ophthalmic Field

Clinical use of a 3-dimensional ultrasonography system with a new ophthalmic imaging device using conventional 2-dimensional ultrasound tomography in the ophthalmic field was evaluated in 5 patients with different ocular conditions. With the system, surface rendering and volume measurement were easy in 3-dimensional ultrasonographic examinations. In a patient with rhegmatogenous retinal detachment, the surface rendering made the image cube transparent, revealing interior surface details. In a patient with lens luxation resulting from Marfan's syndrome, the shape of luxated spherophakia was detected stereographically. In a patient with choroidal detachment, we could evaluate the effect of administration of aspirin on the amelioration of this disease by measuring the volume of the choroidal lesion. In a patient with aberration of a lens fragment into subretinal space during cataract surgery, we grasped the whole ocular condition in the 3-dimensional image only by just one manipulation. In a patient with optic disc melanocytoma, we could detect the volume change in detail using the 3-dimensional images-saving system. No discomfort occurred in these patients during examination. Based upon the above findings, we considered that this device was useful in making diagnosis and grasping the whole ocular conditions and outcome in breathtaking 3-dimensional views, and in causing no discomfort for patients

Regulation of hepatitis C virus secretion by the Hrs-dependent exosomal pathway

AbstractThe molecular mechanisms of assembly and budding of hepatitis C virus (HCV) remain poorly understood. The budding of several enveloped viruses requires an endosomal sorting complex required for transport (ESCRT), which is part of the cellular machinery used to form multivesicular bodies (MVBs). Here, we demonstrated that Hrs, an ESCRT-0 component, is critical for the budding of HCV through the exosomal secretion pathway. Hrs depletion caused reduced exosome production, which paralleled with the decrease of HCV replication in the host cell, and that in the culture supernatant. Sucrose-density gradient separation of the culture supernatant of HCV-infected cells revealed the co-existence of HCV core proteins and the exosome marker. Furthermore, both the core protein and an envelope protein of HCV were detected in the intraluminal vesicles of MVBs. These results suggested that HCV secretion from host cells requires Hrs-dependent exosomal pathway in which the viral assembly is also involved