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Biomedical subjects

S Inokuchi

Publications and source records attributed to S Inokuchi.

At least 19 recordsLinked to original sources
PubMed2001

Injection of CD4(+) and CD8(+) cells with donor or host accessory cells induces acute graft-vs-host disease in human skin in immunodeficient mice.

OBJECTIVE: We examined cell subsets with respect to cutaneous graft-vs-host disease by cell sorting selection of subsets of human mononuclear cells and injecting the subsets subcutaneously in a mouse model. MATERIALS AND METHODS: Cell suspensions containing cultured human epidermal cells and dermal fibroblasts from a single donor mixed with lymphoid cell subsets positively selected using the FACSVantage cell sorting instrument and/or MACS cell isolation kits from unrelated individuals were injected into immunodeficient mice. This model is known to generate human skin with histologic findings similar to human graft-vs-host disease. RESULTS: Donor T-cell subsets CD4(+) and CD8(+) plus either host or donor CD14(+) cells were necessary to cause acute cutaneous graft-vs-host disease. Although graft-vs-host disease can result from recognition of class I antigens expressed on human cutaneous cells by donor peripheral blood mononuclear cells, additional recognition of class II antigens expressed on host mononuclear cells resulted in more severe histologic manifestations. Dendritic cells that differentiated from donor and host monocytes also showed competent accessory cell function in this system. CONCLUSIONS: Based on this model, human cutaneous graft-vs-host disease was caused by donor CD4(+) cells and CD8(+) cells activated through recognition of host antigens, including class I and class II antigens presented by either donor or host CD14(+) cells or dendritic cells.

Animals↗
PubMed2001

Hyperplastic vascular smooth muscle cells of the intrarenal arteries in angiotensin II type 1a receptor null mutant mice.

BACKGROUND: Angiotensin II (Ang II), which contracts vascular smooth muscle cells (VSMCs), has been reported to regulate VSMC growth. Recently formed transgenic mice without angiotensinogen or Ang II receptors showed vascular alterations. However, it is still unclear how their VSMCs alter. We explored the role of Ang II via the Ang II type 1a receptor (AT1a) in VSMCs in vivo using AT1a null mutant mice. METHODS: We analyzed the ultrastructure of the intrarenal arteries in AT1a null mutant mice that were homozygous for a targeted disruption of AT1a receptor gene using light and electron microscopy. RESULTS: The structural changes of the intrarenal arteries in AT1a null mutant mice showed the wall thickening, which in the interlobar, arcuate, and proximal interlobular arteries consisted of two additional populations of VSMCs, on the luminal and abluminal sides of the media. The luminal overpopulation of smooth muscle cells (SMCs) was arranged in a longitudinal direction separated by increased interposed elastic laminae. The abluminal overpopulation of SMCs ran in circumferential directions separated from the main population. The cytological structure of VSMCs in AT1a null mutant mice was smaller in size, contained more organelles for protein synthesis and secretion than in control mice, and had poorly developed contractile apparatus. CONCLUSIONS: The lack of AT1a signaling causes structural abnormalities in the renal vascular system and transforms the phenotype of VSMCs into cell proliferation, induces the escape of VSMCs from the circular mechanical integrity, and results in increased synthesis of extracellular matrices.

Animals↗
PubMed2001

Accumulation of p53 in esophageal squamous cell carcinoma.

p53 is one of the most important tumor suppressor genes. Mutation of the p53 gene can be detected immunohistochemically as over-expression of its protein in the nucleus. The p53 gene product is known to regulate cell growth and proliferation. Genetic alterations related to the carcinogenesis or progression of esophageal cancer are poorly understood. We examined accumulation of p53 protein in esophageal squamous cell carcinomas including early-stage cancers, and its clinicopathological significance. p53 immunoreactivity in the cancer tissues was found in 61 (79.2%) of 77 esophageal squamous cell carcinomas. Over-expression of p53 protein (diffusely and focally positive staining) was seen in 70.1% (54/77). p53 over-expression was detected not only in the cases of in situ or intramucosal carcinomas, but also in invasive carcinomas. No significant correlations were found between p53 over-expression and clinicopathological features such as depth of tumor invasion, lymph node metastasis or venous/lymphatic invasion. These results suggested that p53 mutations may be closely associated with the early-stage of pre-invasive esophageal carcinoma, and p53 gene mutations may play an important role in the carcinogenesis of human esophageal cancer.

Aged↗
PubMed2001

Three dimensional ultrastructure of transverse (Harris) lines in the long bone.

To investigate the occurrence of transverse lines in long bones of adults, we studied 27 cadavers (14 males and 13 females). After confirming the presence of a transverse line, a cross-sectional sample was examined macroscopically, and by soft X-ray and scanning electron microscopy. The following results were obtained: 1. According to roentgenograms, transverse (Harris') lines were observed in 40.7% of the distal half of the femur and in 29.6% of the proximal half of the tibia. 2. Macroscopic examination of the bone cross-sections at the level of the transverse line showed various membranous structures. 3. In scanning electron micrographs, no marked difference in structure was observed between the transverse line trabeculae and the compact bone.

Aged↗
PubMed2001

A patient with diabetes mellitus and severe arterial embolism.

An 89-year-old man with diabetes mellitus was admitted to the hospital because of a low-grade fever and a disturbance in consciousness. He had been diagnosed as having diabetes mellitus at the age of 22 years and had been taking oral hypoglycemic drugs for 16 years at least. A few days before admission, a loss of appetite was noticed by his family; he developed a stupor on the day of admission. On physical examination, his lower extremities were pale and his skin temperature was low. Laboratory tests showed an increase in his white blood cell count and his blood culture was positive for Staphylococcus aureus. An MRI showed that the abdominal aorta was totally occluded beneath the renal arteries, and no significant collateral circulation was observed. He was given antibiotics and anticoagulants, but his general condition continued to worsen. Laboratory tests showed renal failure and liver dysfunction, indicating multi-organ failure. On the 24th day of admission, he died of respiratory and heart failure. An autopsy showed the aorta to be totally occluded beneath the renal arteries by an embolism; atherosclerotic changes were rather mild. Acute plaque change on the surface of the aorta may have induced the sudden development of emboli in the aorta.

Acute Kidney Injury↗
PubMed2001

Effects of physical training and mental practice of in-clothes swimming: assessment by physiological parameters.

PURPOSE: This study examined whether a short-term physical or mental training reduces the physiological load and perceived exertion of the in-clothes swimming. METHODS: The study included 24 male inter-collegiate competitive swimmers with no previous experience of the in-clothes swimming. Prior to the training, the subjects performed 200-meter swimming with two styles of swimming, namely the crawl and elementary backstroke, and the degree of perceived exertion in the Borg scale, heart rate, and blood lactic acid level were determined. Following this baseline determination, the subjects were divided into 4 groups with 6 individuals each. These four groups were Group A "in-clothes training", Group B "image training", Group C "swimsuit training", and Group N "no training". Group A and C were lectured on the in-clothes swimming and practiced 7.5 min-long in-clothes swimming per day for a week with the two swimming styles, with Group A subjects wearing daily clothes and Group C subjects in swimsuits. Group B received 15 min of nonphysical mental practice primarily through viewing video recording of swimming performance everyday for a week. No training was given to Group N. At the completion of the training session, the subjects underwent the 2nd 200-meter swimming, and the physiological parameters were determined. RESULTS: The 1st in-clothes swimming load test showed that the elementary backstroke swimming resulted in significantly lower values of heart rate, blood lactic acid level, and perceived exertion than the crawl. For Group N, no difference was observed in the physiological parameters between the 1st and 2nd load test with either the elementary backstroke or crawl. Upon the 2nd in-clothes load test with the elementary backstroke, all three parameters were lower for Group A, B, and C than those seen for the 1st load test, and these differences were statistically significant, except for blood lactic acid in Group A. The 2nd in-clothes load test with the crawl showed that both heart rate and blood lactic acid were lower than those of the 1st load test for all three groups, with the differences in heart rate and blood lactic acid in Group A and that in blood lactic acid in Group B reaching the statistic significance. With respect to perceived exertion, the Borg score determined after the in-clothes load test with the crawl was significantly reduced for Group A, B, and C. The score after the in-clothes load test with the elementary backstroke was significantly reduced only for Group A. CONCLUSION: The elementary backstroke, when practiced in-clothes, imposes a relatively less physiological load. The present training methods can reduce physiological load and/or perceived exertion of the in-clothes swimming. Thus, both image training and swimsuit swimming are equally effective as a training method of the in-clothes swimming.

Adult↗
PubMed2000

Study for verification testing of the helmet-mounted display in the Japanese Experimental Module.

Our purpose is to propose a research and development project in the field of telemedicine. The proposed Multimedia Telemedicine Experiment for Extra-Vehicular Activity will entail experiments designed to support astronaut health management during Extra-Vehicular Activity (EVA). Experiments will have relevant applications to the Japanese Experimental Module (JEM) operated by National Space Development Agency of Japan (NASDA) for the International Space Station (ISS). In essence, this is a proposal for verification testing of the Helmet-Mounted Display (HMD), which enables astronauts to verify their own blood pressures and electrocardiograms, and to view a display of instructions from the ground station and listings of work procedures. Specifically, HMD is a device designed to project images and data inside the astronaut's helmet. We consider this R&D proposal to be one of the most suitable projects under consideration in response to NASDA's open invitation calling for medical experiments to be conducted on JEM.

Data Display↗
PubMed2000

Intravenous mycophenolate mofetil: safety, tolerability, and pharmacokinetics.

An intravenous (i.v.) formulation of mycophenolate mofetil (MMF; CellCept, Roche Pharmaceuticals, Inc., Palo Alto, CA) that will enable its administration to patients unable to tolerate oral medication is available. Two separate studies, an open-labeled pharmacokinetic (PK) study and a double-blind safety study, were performed. Within 24 h after transplant, 153 (safety study) and 45 (PK study) first or second renal transplant recipients were started on i.v. MMF 1 g Q12h or placebo (used in the safety study only, 2:1 MMF:placebo), given over 2 h via a dedicated peripheral venous catheter. In the safety study, per os (p.o.) MMF (1g Q12h) or placebo was administered, starting within 72 h after transplant, whereas in the PK study, p.o. MMF was started on the evening of day 5. Sequential blood samples obtained on study days 5 (i.v. MMF) and 6 (p.o. MMF) before and up to 12 h after the AM dose were analyzed for mycophenolic acid (MPA) and MPA glucuronide (MPAG) concentrations by high-performance liquid chromatography. The area under the concentration curve (AUC) was calculated using the linear trapezoidal rule. The MPA AUC(0-12) was higher for i.v. MMF than p.o. MMF (40.8 +/- 11.4 microg x h/ mL vs. 32.9 +/- 15, p < 0.001). There were no other significant PK differences for plasma MPA or MPAG. In the safety study (n = 98 i.v. MMF vs. n = 55 placebo), 11 patients (11%, i.v. MMF) and 4 patients (7%, placebo) discontinued their use of the drug because of an adverse event (AE). Overall, AEs were similar between i.v. MMF and placebo. Injection site phlebitis (4%) and thrombosis (4%) were observed only with i.v. MMF. MMF i.v. 1 g twice daily (b.i.d.) should provide efficacy at least equivalent to p.o. MMF without increased toxicity, and it provides an acceptable alternative dose form in the immediate period after transplant.

Administration, Oral↗
PubMed2000

Correlating the severity of paraquat poisoning with specific hemodynamic and oxygen metabolism variables.

OBJECTIVE: To investigate the hemodynamics and oxygen metabolism of patients with varying degrees of severity of paraquat poisoning. DESIGN: Prospective, observational, clinical study. SETTING: Intensive care unit in a university hospital. PATIENTS: Forty-three consecutive patients with paraquat and/or diquat poisoning were classified into three groups by the severity index of paraquat poisoning (SIPP; hr/mg/L). INTERVENTIONS: Standard treatments included specific respiratory management, fluid resuscitation, and aggressive circulatory support. MEASUREMENTS AND MAIN RESULTS: Serum paraquat and diquat levels were measured at arrival, and SIPP was calculated. The cardiac index (CI), left ventricular stroke work index (LVSWI), systemic vascular resistance index (SVRI), oxygen delivery index (DO2I), oxygen consumption index (VO2I), and oxygen extraction ratio (O2ER) were measured at 6, 12, 24, 36, 48, 72, and 96 hrs postadmission. A significant inverse correlation between SIPP and survival time was found in 31 fatal cases (r = .85; p < .001). In the SIPP 10-50 group, CI, DO2I, VO2I, and O2ER were maintained at higher levels than in the SIPP group of <10 (p < .05), whereas SVRI decreased significantly (p < .05). In the SIPP group of >50, CI, LVSWI, SVRI, DO2I, and VO2I decreased, whereas O2ER had a tendency to increase progressively. There was a significant correlation between SVRI and SIPP, O2ER and SIPP, and O2ER and SVRI 24 hrs after admission, respectively (p < .001). CONCLUSIONS: Paraquat poisoning is characterized by high oxygen consumption with high oxygen extraction, with the degree of derangement based on the severity index. The development of a marked imbalance between increased oxygen demand and decreased oxygen supply because of myocardial depression might be a possible cause of death in circulatory failure.

Adolescent↗
PubMed2000

Clinical application of artificial ligament for ankle instability--long-term follow-up.

We have applied a reconstructive operation to patients with injury of the lateral ligament in the ankle joint using an artificial ligament made of polyester (Leeds-Keio) since 1985. The operation was performed on 451 feet of 436 patients. Average follow-up period was 5 years and 8 months. Talar tilt and anterior drawer translation before and after the operation were improved from 16 degrees to 4 degrees and from 11 mm to 4 mm, respectively. In this study, which has followed the same patients over an extended period, there were no cases with a decrease in the range of motion of the joint, with further development of osteoarthritis, or with a poorer result than those observed in our earlier study, which reported a short-term follow-up of the same patients. It may therefore be concluded that this reconstructive procedure of the lateral ligament of the ankle joint, using the artificial ligament, is also excellent after long-term follow-up.

Adolescent↗
PubMed1999

Rapid ex vivo expansion of human umbilical cord hematopoietic progenitors using a novel culture system.

Cell numbers limit the widespread clinical use of cord blood (CB) for gene therapy and marrow replacement in adults; a simple and effective method for ex vivo expansion of CB primitive progenitor cells (PPC) is required. Recently, the combination of thrombopoietin (TPO) and Flk-2/Flt-3 ligand (FL-2) was reported to support slow proliferation of CB-PPC in stroma-free liquid culture. We established a novel culture system in which the murine stromal cell line HESS-5 dramatically supports the rapid expansion of cryopreserved CB-PPC in synergy with TPO/FL-2. Furthermore, while HESS-5 cells directly adhered to human progenitors during culture, the cultured human cells could easily be harvested without contamination by HESS-5 cells. Within 7 days of culture, a 100-fold increase in CD34bright/CD38dim cells was obtained in serum-containing culture. When HESS-5 cells were physically separated from human progenitor cells in the presence of TPO/FL-2, synergy was blocked, suggesting that HESS-5 cells support proliferation of PPC by direct cell-to-cell interaction. The hematopoietic-supportive effects of this xenogeneic coculture system were then assessed in a very short-term (5 days) serum-free culture. Expansion was further enhanced by addition of stem cell factor (SCF) or interleukin-3 (IL-3). As a result, a 50- to 100-fold increase in CD34bright/CD38dim cells was noted. Colony-forming units in culture (CFU-C) and mixed colonies (CFU-GEMM) were enhanced by 10- to 30-fold and 10- to 20-fold, respectively. Moreover, generation of long-term-culture-initiating cells (LTC-IC) from CD34bright/CD38dim cells was amplified by 25-fold. The severe-combined immunodeficient (SCID) mouse-repopulating cell (SRC) assay confirmed extensive ability of the expanded cells to reconstitute long-term hematopoiesis. These results indicate that this xenogeneic coculture system, in combination with human cytokines, can rapidly generate PPC from cryopreserved CB.

Animals↗
PubMed1999

An in vivo model of human skin acute graft-versus-host disease: transplantation of cultured human epidermal cells and dermal fibroblasts with human lymphocytes into SCID mice.

The ability of mixed epidermal cell-lymphocyte reactions to detect allogeneic reactivities in an in vivo model was investigated by developing an in vivo model of acute graft-versus-host disease (GVHD), using SCID mice with a C.B-17 background in which human skin structures were generated by transplantation of cultured human epidermal cells (HEC) with dermal fibroblasts (HDFC). Suspensions containing cultured HEC and HDFC from a single donor were mixed with autologous peripheral blood mononuclear cells (PBMNC) or with PBMNC from unrelated individuals, and were injected into the flanks of C.B-17-SCID mice. Ten and 21 days after injection, subcutaneous nodules generated in the mice were examined histologically and immunohistochemically. Cystic structures developing after injection of HEC and HDFC without human PBMNC showed normal epidermislike tissue. Human skin generated in SCID mice injected with HEC and HDFC with auto-PBMNC showed no graft-versus-host reaction (GVHR) histologically, whereas those mice injected with PBMNC from siblings that shared an HLA haplotype showed mild GVHR. Human skin in SCID mice injected with HEC and HDFC with histoincompatible unrelated PBMNC showed moderate to severe GVHR. The severity of GVHR paralleled the dose of unrelated PBMNC, and GVHR was prevented by peroral treatment with cyclosporine A. Immunohistochemically, inflammatory cells infiltrating human cutaneous tissue formed in the SCID mice were stained by an anti-human CD45RO antibody that reacts with human T cells but not with murine lymphocytes, and most T cells were stained by an anti-human CD8 antibody recognizing HLA class I antigens. These findings are similar to those in clinical skin graft-versus host disease (GVHD) observed in patients undergoing allogeneic bone marrow transplantation. This experimental system should be useful as an in vivo model of human skin GVHD.

Animals↗
PubMed1999

The effects of tensile load on the metabolism of cultured chondrocytes.

The effect of cyclic tensile load on articular cartilage metabolism was investigated experimentally using 12 Japanese White rabbits. Chondrocytes obtained from the knee joints were cultured on plates with flexible silicone rubber bases. They were subjected to a cyclic (3 seconds on and 3 seconds off) tensile load for 24 hours with a maximum increase in area of 17%. Proteoglycan synthesis, collagen synthesis, and tissue inhibitors of metalloproteinases production by the chondrocytes under the load were quantified and compared with those produced by the control cells in an unloaded condition. The cultured chondrocytes under the cyclic tensile load perpendicularly aligned to the direction of the tensile load. Collagen synthesis and tissue inhibitors of metalloproteinases production increased significantly under the cyclic tensile load, although no significant change in proteoglycan synthesis was observed. These results suggested that the cyclic tensile load on the chondrocytes contribute to the regulation of articular cartilage metabolism in part.

Animals↗
PubMed1998

Angiotensin II maintains the structure and function of glomerular mesangium via type 1a receptor. What we have learned from null mutant mice minus the angiotensin II type 1a receptor gene.

The angiotensin II type 1a (AT1a) receptor is the major receptor effecting the multiple actions of angiotensin II on the cardiovascular system. It is expressed abundantly in the glomerular mesangial cells of the kidney. We investigated glomerular changes in null mutant mice minus the AT1a receptor gene to gain an understanding of the in vivo action of angiotensin II via AT1a on the mesangium. Morphological observations and morphometric analysis revealed that the glomerular volume was greatly increased owing to the expansion of the mesangial area, which contained fluid-filled spaces with a small amount of fibrillar components. The mesangial cells lost contact with each other and with the perimesangial area of the glomerular basement membrane (GBM), so that the glomerular capillary neck was greatly widened. These findings suggest a defect of the anchoring function of mesangial cells resulting from some abnormality in mesangial matrix formation. We conclude that angiotensin II has an important role in the structural and functional maintenance of the mesangium via the AT1a receptor, especially by reinforcing the connection between mesangial cells and GBM via the mesangial matrix.

Angiotensin II↗
PubMed1998

Histological and immunocytochemical studies of human psoriatic lesions transplanted onto SCID mice.

To investigate the pathology of psoriasis, we developed an animal model for this disease using severe combined immunodeficiency (SCID) mice. These mice possess neither B nor T Lymphocytes so that both cellular and humoral immunities are impaired. For the in vivo study of psoriasis, human psoriatic skin was grafted on SCID mice. Long-term morphological and immunohistochemical changes in the grafted skin ware examined for up to 22 weeks after transplantation. The human skin graft were generally well maintained during this period, but the histological and immunohistochemical findings characteristic of psoriasis, except for acanthosis and hyperkeratosis, gradually disappeared as lymphocytic infiltration of the psoriatic lesions declined.

Adult↗
PubMed1998

The new-concept full-face-type helmet with removable cheek pads.

BACKGROUND: The American College of Surgeons proposed a method of removing helmets. But the problem with full-face-type helmets is that their shape makes them difficult to remove. METHODS: A dummy doll was fixed to a smooth bed surface in the supine position, and a full-face-type helmet with a hook attached to the vertex was placed on the doll's head. A spring balance was attached to the hook, traction was applied to the helmet through the spring balance, and the maximum tension needed to completely remove the helmet was measured. RESULTS: A tension of 13.2 +/- 1.8 kg was found. But when cheek pads were removed, the tension required to remove the helmet was 1.7 +/- 0.2 kg. CONCLUSION: We devised a full-face-type helmet that uses removable cheek pads so that helmet removal can be performed safely by removing only the cheek pads in the event of an accident.

Cervical Vertebrae↗
PubMed1998

A simple and efficient purification of transduced cells by using green fluorescent protein gene as a selection marker.

BACKGROUND: Simple and efficient method for the selection of transduced cells would greatly facilitate the clinical utilization of retrovirus vectors. We developed a therapeutic bicistronic retrovirus vector for Gaucher disease, MFG-GC-GFP, which contains the human glucocerebrosidase (GC) gene and the green fluorescent protein (GFP) gene of the jellyfish Aequorea victoria as a vital selection marker, and investigated its applicability as gene therapy for Gaucher disease. METHODS AND RESULTS: A packaging cell line, GP + envAM12, was transfected with MFG-GC-GFP and, thus, produced a high titer recombinant virus (1.0 x 10(6) c.f.u./mL) in the culture supernatant. The expression level of GFP was correlated with the virus production in cells. The recombinant virus infected skin fibroblasts from a Gaucher patient and a sorted fraction of the cells expressing GFP by flow cytometry exhibited almost a six-fold higher activity of GC than normal fibroblasts. CONCLUSIONS: These data indicate that MFG-GC-GFP enables the one-step purification of a transduced fraction of target cells and is, therefore, considered to be a useful therapeutic vector for the experimental gene therapy of Gaucher disease.

Animals↗