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H Kameyama

Publications and source records attributed to H Kameyama.

At least 19 recordsLinked to original sources
PubMed2006

Histological analysis on adhesive molecules of renal intravascular large B cell lymphoma treated with CHOP chemotherapy and rituximab.

A 48-year-old man was admitted to our hospital for investigation of mild renal dysfunction. A blood examination revealed mild elevation of creatinine level (1.77 mg/dl). Urinary examination revealed mild protein excretion (0.54 g/day) and microhematuria; renal biopsy revealed the focal proliferation of large mononuclear cells with mitosis in glomerular capillaries. According to immunohistochemical analysis, the intravascular lymphomatous cells stained positively with anti-leukocyte common antigen (LCA: CD45) and CD20, indicating a B lymphocyte lineage. In electron microscopy, the glomerular capillary was filled with lymphoma cells and epithelial foot process fusion was noted. Immunohistochemical analysis on adhesive molecules revealed a lack of CD11a expression on lymphoma cells, but positive CD54 expression on endothelial cells. Systemic 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) revealed no abnormal uptake of isotopes. On the basis of these findings, we diagnosed intravascular diffuse large B cell lymphoma localized in the kidney. Despite treatment with rituximab and CHOP (prednisolone, doxorubicin, vincristine, cyclophosphamide) for 3 cycles at 1-month intervals, the renal dysfunction did not change. In histopathological analysis of the second biopsy, lymphoma cells disappeared, but focal segmental glomerulosclerosis and moderate interstitial fibrosis were noted. Electron microscopic findings revealed severe subendothelial edema with mesangial interposition, indicating severe endothelial damage. Epithelial foot process fusion was improved. These pathological analyses let us conclude that a lack of CD11a could be a candidate factor for prevention of the extravasation of lymphoma cells from blood vessels in our patient. We also presumed that the intraglomerular endothelial damage occurred due to chemotherapy-associated cell injury.

Antibodies, Monoclonal↗
PubMed2004

Changes in serum LECT 2 levels during the early period of liver regeneration after adult living related donor liver transplantation.

We investigated changes in serum leukocyte cell-derived chemotaxin2 (LECT2) levels between donors and recipients in the early period during liver regeneration following adult living related donor liver transplantation (LRDLT). Five recipients (three women, two men; 37.0 +/- 15.8 years old), all of whom had end-stage liver failure, underwent LRDLT from healthy five donors (two women, three men; 41.6 +/- 14.3 years old) between June 2000 and February 2001. FK506 and methylprednisolone were used as immunosuppressants for recipients. Serum LECT2 levels decreased immediately after both the hepatectomy in all donors and the implantation of liver graft in all recipients. Donors showed a nadir at 3 to 12 hours, increasing at 24 to 48 hours. The nadir in recipients occurred several hours after the donors. The serum LECT2 levels of donors were significantly higher than those of recipients on day 5 (9.5 +/- 5.9 ng/mL vs 3.1 +/- 2.2 ng/mL, P = .04) and on day 7 (9.3 +/- 3.8 ng/mL vs 3.5 +/- 1.1 ng/mL, P = .04). Serum GPT and GOT levels were inversely proportionate to the serum LECT2 levels. The present studies suggest that LECT2 participates in liver regeneration and injury following hepatectomy.

Adult↗
PubMed2004

Serum LECT2 level as a prognostic indicator in acute liver failure.

In the present study, we investigated the relationship between serum leukocyte cell-derived chemotaxin2 (LECT2) levels and liver function in patients with acute liver failure, and its use as a prognostic indicator. We studied six acute liver failure patients (two women, four men; 49.8 +/- 20.7 years old) admitted to our hospital in 2002. These patients had diagnoses of fulminant hepatitis due to acute liver failure (1) from congestive heart failure; (2) from portal venous gas, and (3) from postoperative disseminated intravascular coagulation (DIC). We measured serum LECT2, GOT, and GPT levels, the last two being inversely proportionate to the serum LECT2 levels. When the serum GPT levels peaked, the serum LECT2 levels were the lowest. When the liver function recovered, serum LECT2 levels increased. Three of four patients died due to liver failure, one to congestive heart failure. Maximum serum LECT2 levels among the expired group were significantly lower than those among the alive group (0.96 +/- 0.8 ng/mL vs 12.9 +/- 4.3 ng/mL). Serum LECT2 levels may be a prognostic indicator of recovery from liver failure. The present study suggests that in clinical medicine LECT2 participates in regeneration after injury of hepatocytes.

Adult↗
PubMed2002

Simultaneous activation of natural killer T cells and autoantibody production in mice injected with denatured syngeneic liver tissue.

Denatured syngeneic liver tissue prepared by mechanical procedures was intraperitoneally injected into adult C57BL/6 mice. In parallel with a decrease in the total number of lymphocytes in the liver, spleen, and thymus from days 1-7 after the injection, the proportion of the CD4+NK1.1+CD3(int) subset of these cells (i.e. natural killer T or NKT cells) increased in the liver. Even the absolute number of these NKT cells increased in the liver on days 14 and 21. In response to the injection of denatured liver tissue, tissue damage was induced in the liver, as shown by elevated levels of serum transaminases and hepatocyte degeneration observed by electron microscopy. Sera obtained on days 7 and 14 contained autoantibodies including anti-DNA antibodies. The proportion of CD1d(high)B cells in the liver was found to decrease on days 1-7. In other words, denatured liver tissue stimulated both NKT cells and certain B cells in the liver. These results suggest that liver lymphocytes might contain not only autoreactive T cells (e.g. CD3(int) or NKT cells) but also some B cells (e.g. B-1 cells) which produce autoantibodies and that the denatured tissue had the potential to stimulate these lymphocytes and to evoke an autoimmune-like state.

Animals↗
PubMed2001

Abundance of unconventional CD8(+) natural killer T cells in the large intestine.

Natural killer T (NKT) cells are mainly present in the liver and thymus, and the majority of these T cells express either a CD4(+) or a double-negative (DN) CD4(-)8(-) phenotype. In the present study, we examined whether such NKT cells were present in the intestine. NKT cells were rare in all sites of the small intestine, including an intraepithelial site. However, a considerable number of NKT cells were found at an intraepithelial site in the large intestine. This result was confirmed by both immunofluorescence and immunohistochemistry. In contrast to conventional NKT cells, NKT cells in the large intestine were CD8(+) or DN CD4(-)8(-). In the case of conventional NKT cells, their existence is known to depend on non-classical MHC class I-like antigens (i. e. CD1d) but not on classical MHC class I antigens. However, the NKT cells in the large intestine were independent of the presence of both CD1d and classical MHC class I antigens. These results were obtained using knockout mice lacking the corresponding genes and molecules. NKT cells in the large intestine were mainly alpha betaTCR(+) (> 75 %) but did not use an invariant chain of Valpha14Jalpha281, which is preferentially used by conventional NKT cells. These NKT cells did not bias the TCR-Vbeta usage toward Vbeta8. These findings suggest that the large intestine is a site in which unconventional NKT cells carrying the CD8(+) phenotype (or DN CD4(-)8(-)) are abundant and that these cells are independent of MHC and MHC-like antigens.

Animals↗
PubMed2001

Size of the population of CD4+ natural killer T cells in the liver is maintained without supply by the thymus during adult life.

Given that there are few natural killer T (NKT) cells in the liver of athymic nude mice and in neonatally thymectomized mice, it is still controversial whether all NKT cells existing in the liver are supplied by the thymus or if some such cells develop in the liver. To determine whether or not NKT cells are consistently supplied from the thymus during adult life, thymectomy was conducted in mice at the age of 8 weeks. Interestingly, the proportion and number of CD4+ NKT cells increased or remained unchanged in the liver after adult thymectomy and this phenomenon continued for up to 6 months after thymectomy. The administration of alpha-galactosylceramide induced severe cytopenia (due to apoptosis) of CD4+ NKT cells in the liver on day 1, but subsequent expansion of these NKT cells occurred in thymectomized mice similar to the case in normal mice. However, in thymectomized mice given lethal irradiation (9.5 Gy) and subsequent bone marrow transfer, the population of CD4+ NKT cells no longer expanded in the liver, although that of CD8+ NKT cells did. These results suggest that thymic CD4+ NKT cells, or their progenitors, may migrate to the liver at a neonatal stage but are not supplied from the thymus in the adult stage under usual conditions. CD8+ NKT cells can be generated in the liver.

Animals↗
PubMed2001

[Malignant lymphoma of the prostate: a case report].

A case of a primary malignant lymphoma of the prostate is presented. An 82-year-old man visited our hospital complaining of anal pain. Digital rectal examination revealed an enlarged prostate gland, which caused a rectal stricture. A computed tomographic scan and magnetic resonance imaging (MRI) showed a large mass arising from the prostate and protruding to the rectum. According to the Working Formulation, he was diagnosed with non-Hodgkin's lymphoma of B-cell origin, diffuse, mixed, small and large cell. The results of bone marrow puncture and imaging studies led to the diagnosis of primary malignant lymphoma of the prostate. Because of poor performance status deriving from severe anal pain, radiation therapy was performed to control the pain. After improvement of his performance status, he received combination chemotherapy consisting of cyclophosphamide, adriamycin, vincristine and predonisone (CHOP regimen). His prostate markedly diminished in size, but pneumonia developed. His respiratory condition rapidly deteriorated, and he died of respiratory failure about two and a half months after the onset of his illness. Malignant lymphoma involving the prostate, whether primary or secondary, is very rare. In our understanding, this case is thought to be the 28th clinical case of a malignant lymphoma of the prostate in Japan.

Aged↗
PubMed1999

Nerve growth factor inducer, 4-methyl catechol, potentiates central sensitization associated with acceleration of spinal glutamate release after mustard oil paw injection in rats.

1. In rats, injection of mustard oil (MO) into the paw caused a gradual increase in flinching of the injected paw and this algogenic behavior corresponded with an increase in the CSF-Glu level. 2. The nerve growth factor (NGF) inducer, 4-methyl catechol (4MC), enhanced the frequency of flinching and this effect was dose dependent. In addition, spinal CSF-Glu release was significantly above baseline 10 min after MO injection. In contrast, morphine (MOR) pretreatment completely blocked this behavioral and neurohumoral effect. 3. Anti-NGF paw injection attenuated the algogenic behavior and spinal Glu release otherwise observed after 4MC treatment. 4. The results demonstrated that MO-induced hyperalgesia is associated with increased CSF-Glu release and that this effect is potentiated by a NGF inducer. These data also suggest a possible involvement of NGF in the development of central sensitization after acute peripheral nociceptive stimulation.

Analgesics, Opioid↗
PubMed1997

Endoscopic ultrasonography in the diagnosis of submucosal lesions of the large intestine.

BACKGROUND: Although reports of colorectal submucosal tumors have increased since the development of endoscopic examinations, precise diagnosis of these lesions remains difficult. In this study, we evaluated the usefulness of endoscopic ultrasonography (EUS) in the diagnosis of submucosal lesions of the large intestine. METHODS: From September 1989 to June 1996, EUS was performed in 46 patients who were suspected to have submucosal lesions by barium enema or colonoscopy. Twenty-seven of the 46 cases were confirmed histologically by endoscopic or surgical resection, and their ultrasonographic images were compared with resection specimens. RESULTS: Lipomas (n = 15) were visualized as hyperechoic masses and lymphangiomas (n = 9) visualized as cystic lesions with septal structures as characteristic findings. The EUS images of leiomyomas (n = 6), leiomyosarcomas (n = 3), and enteric endometriosis (n = 7) were all hypoechoic masses in the fourth layer. Leiomyosarcomas tended to be larger and more inhomogeneous than leiomyomas. Enteric endometriosis was shaped like a spindle or a half-moon, and myogenic tumors were lobulated when the lesions were large. Recurrences of colorectal carcinoma (n = 3), malignant lymphomas (n = 2), and an appendiceal mucocele (n = 1) were examined. CONCLUSIONS: EUS is useful in the diagnosis of submucosal lesions of the large intestine because it provides precise information about these lesions.

Adult↗
PubMed1996

Distribution of phosphoneuroprotein 14 (PNP 14) in vertebrates: its levels as determined by enzyme immunoassay.

We have established an enzyme immunoassay for phosphoneuroprotein 14 (PNP 14) which is mainly localized in the cytoplasmic matrix in presynaptic axon terminals and which is phosphorylated in vivo, as well as in vitro. Fab' prepared from rabbit IgG antibodies against bovine PNP 14 was conjugated with maleimide-horseradish peroxidase. The enzyme-conjugated Fab' was used as a second antibody in a sandwich enzyme immunoassay. This assay was able accurately to quantify 0.5-100 ng of rat PNP 14, as well as bovine PNP 14, and it was used for the determination of concentrations of PNP 14 in various rat tissues, neuroblastoma cells, and brains of other vertebrates. The concentrations of PNP 14 in the rat cerebrum, cerebellum, and testis were 1.1, 1.0, and 0.28 micrograms/mg of protein, respectively, and those in other tissues examined were less than 0.1 microgram/mg of protein. PNP 14 was also found in cultured cells, such as rat pheochromocytoma PC12 cells, NG108-15 cells, which are a hybrid between a mouse neuroblastoma and a rat glioma, mouse neuroblastoma Neuro-2a cells, and human neuroblastoma IMR32 cells. Furthermore, PNP 14-specific immunoreactivity was evaluated in the brains of various vertebrates, such as fish, frog, snake and chicken by immunoblot and enzyme immunoassay. The results revealed the immunoreactivity in the brains of all vertebrates examined and the levels were determined to be 0.6-2.1 micrograms bovine PNP 14 equivalents per mg of protein, suggesting that PNP 14 might be an essential component of the central nervous systems of vertebrates.

Animals↗
PubMed1989

Clinical study of radioisotope clearance from the cerebrospinal fluid space using single photon emission computed tomography.

Radioisotope cisternography with statistical analysis was evaluated in 18 patients with suspected hydrocephalus shown by conventional CT, and 4 control patients. Regions of interest were located at cisterna magna, basal cistern, lateral cistern Sylvii, interhemispheric cistern, and lateral ventricle using three dimensional SPECT images. A value for the constant K was determined for each exponential radioactivity decay curve. On the basis of SPECT-derived K values our patients were grouped into hydrocephalus, nonhydrocephalus, and control patients. Twelve of 14 hydrocephalus patients were treated by shunt operation. Our less-invasive method showed reliable criteria for assessing the cerebrospinal fluid circulation.

Adolescent↗