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H Okabe

Publications and source records attributed to H Okabe.

At least 199 records · Page 11Linked to original sources
PubMed1995

Endotoxin-induced pulmonary vascular injury is mainly mediated by activated neutrophils in rats.

Acute respiratory failure is a common complication in patients with disseminated intravascular coagulation associated with sepsis. To elucidate the role of coagulation abnormalities in acute lung injury in sepsis, we investigated the effect of anticoagulants on the pulmonary vascular injury in rat induced by lipopolysaccharide (LPS). When administered intravenously, LPS (5 mg/kg body weight) significantly increased the accumulation of 111indium-labeled neutrophils in lung 30 min after administration. Subsequently, the pulmonary vascular permeability and the serum level of fibrin and fibrinogen degradation products (E) [FDP (E)] increased and remained elevated for several hours. Neither heparin alone, heparin plus antithrombin III, or dansyl-Glu-Gly-Arg-chloromethyl ketone-treated factor Xa, a selective inhibitor of thrombin generation, prevented LPS-induced vascular injury 6 hours after LPS administration, whereas these substances significantly inhibited the increase in serum FDP (E) at that time. LPS-induced pulmonary vascular injury was significantly attenuated in rats with methotrexate-induced leukocytopenia or treated with ONO-5046, a potent granulocyte elastase inhibitor, although ONO-5046 did not inhibit the LPS-induced increase in serum FDP (E). Thus, activated leukocytes play a more important role than coagulation abnormalities in the pathogenesis of LPS-induced pulmonary vascular injury in an experimental rat model of endotoxemia.

Amino Acid Chloromethyl Ketones↗
PubMed1995

Antithrombin III Kumamoto II; a single mutation at Arg393-His increased the affinity of antithrombin III for heparin.

Abnormal antithrombin III (AT III) was found in a 30-year-old woman who suffered from recurrent thrombosis during pregnancy and the postpartum period. Among her family members, only her father had recurrent episodes of deep vein thrombosis of the lower extremities, from his youth. The antithrombin and antifactor Xa heparin cofactor activities of the proposita's plasma were 61% and 42% of normal, respectively. The progressive antithrombin and antifactor Xa activities were also decreased to 55% and 58% of normal, respectively. The immunoreactive level of AT III was within the normal range (23.1 mg/dl). Analysis of the proposita's plasma by crossed immunoelectrophoresis in the presence or absence of heparin and by affinity chromatography on heparin-Sepharose revealed that the proposita's AT III had apparently normal affinity for heparin. Nucleotide sequencing of 7 exons of the proposita's AT III gene amplified by polymerase chain reaction (PCR) disclosed that the second base of codon 393 comprised both G and A, indicating Arg393-His conversion. The base sequences of exons 1, 2, 3a, 3b, 4, and 5 were normal, excluding any other mutation. These findings indicated that the proposita's AT III was a variant of AT III at the thrombin binding site and that the proposita was a heterozygote for the abnormality. Heparin affinity of purified abnormal AT III from the proposita's plasma was demonstrated to be increased upon affinity chromatography using heparin-Sepharose, suggesting that the mutation (Arg393-His) per se could possibly increase the affinity of antithrombin III for heparin. For this variant AT III (Arg393-His), the name AT III Kumamoto II is proposed.

Adult↗
PubMed1995

Comparison of monoclonal and polyclonal enzyme-linked immunoabsorbent (ELISA) assays for serum Lp(a) and differences in reactivities to Lp(a) phenotypes.

We have prepared a monoclonal antibody to Lipoprotein(a)[Lp(a)] and have used it to develop an ELISA test for assaying Lp(a) in serum. The monoclonal antibody employed in the assay system reacts uniformly with S1, S2, S3 and B phenotypes of isoforms, and no cross-reaction with plasminogen at a concentration of 100 mg/dL was observed. Results of the monoclonal ELISA assay were similar to those obtained with a polyclonal antibody ELISA method and demonstrated a correlation coefficient, r = 0.99 with the equation for the regression line: Y(proposed) = 1.06 x (polyclonal antibody reference ELISA test) = 0.36 (N = 51). Inter- and intra-assay precision(CVs) of the monoclonal ELISA assay were between 2.2-3.6% at a mean Lp(a) concentration range of 19.1-68.2 mg/dL,(N = 12). Assay results of various standards were compared by both monoclonal and polyclonal antibody ELISA tests. We observed some discrepancies between expected concentrations and the polyclonal antibody ELISA assay results, which is thought to be more uniformly reactive to the various Lp(a) phenotypes. The monoclonal antibody employed in our proposed method reacts uniformly with Lp(a) phenotypes, and the assay exhibits excellent sensitivity, specificity, and accuracy and is well suited for clinical use.

Adult↗
PubMed1995

Anaplastic large cell Ki-1 lymphoma with bone involvement: report of two cases.

Two cases of anaplastic large cell Ki-1 lymphoma involving bone as the most prominent and initial manifestation are reported. The first patient was a 20-year-old male who had back pain and incomplete paraparesis due to vertebral involvement. The second was a 14-year-old girl, whose first clinical signs were fever of unknown origin and sternal bone pain. Radiologically, skeletal lesions were lytic and destructive. Histopathologically, the tumour cells had pleomorphic bizarre nuclei and abundant basophilic cytoplasm. Immunohistochemically, Ki-1(CD30) reactivity was strongly positive in both cases. Tumour cells were also CD3, CD4, epithelial membrane antigen and interleukin-2 receptor positive in the first case, and CD10, HLA-DR positive in the second case. The former tumour was considered to be of T-cell lineage and the latter of lymphoid progenitor cell origin. Radiation and chemotherapy were temporarily effective. However, both patients died 14 and 7 months after diagnosis, respectively, due to systemic lymph node involvement. These observations suggest that the prognosis for Ki-1 lymphoma involving bone is poorer than indicated in previous reports.

Adolescent↗
PubMed1995

Juvenile xanthogranuloma with cutaneous and cerebral manifestations in a young infant.

Juvenile xanthogranuloma is usually a self-limiting disease of the skin. Intracranial manifestations are extremely rare. We report the clinico-pathological features of an 8-month-old boy suffering from a gradually enlarging nodule of the chest wall and subsequent epileptic seizures. The subcutaneous tumor and a cerebral subcortical tumor of the left temporal lobe were resected. The histological appearance of both tumors corresponded to juvenile xanthogranuloma and included histiocytes, foamy cells, giant cells, inflammatory cells, and collagen-producing fibroblasts showing a storiform pattern. Immunohistochemical studies demonstrated positivity of the tumor cells for lysozyme, CD68 and myeloid-histiocytic antigen, but not S-100 protein, supporting mono-histiocytic differentiation. This case indicates that juvenile xanthogranuloma should be considered in the differential diagnosis of intracranial "xanthomatous" and histiocytic lesions.

Antibodies↗
PubMed1995

A super long-acting LH-RH analogue induces regression of hypothalamic hamartoma associated with precocious puberty.

We treated a 1-year-old female with a hypothalamic hamartoma and precocious puberty with leuprolide acetate depot, a super long-acting hormone-releasing hormone analogue (Tap-144-SR; [D-Leu6-[des-Gly10-NH2] LH-RH ethylamide acetate). The infant's major symptoms were genital bleeding and gynaecomastia. The LH-RH analogue (30 micrograms/kg) was injected subcutaneously once every 4 weeks. Clinical and laboratory manifestations of precocious puberty showed marked improvement. A follow-up after 16 months of treatment, the size of the tumour decreased significantly and remained unchanged for 2 years of further follow-up. To the best of our knowledge, this is the first hypothalamic hamartoma case in whom a decrease of tumour size under treatment with LH-RH analogue has been documented. But, because diagnosis of hamartoma is only based on neuroradiological and not on histological examinations, the possibility of a gangliocytoma cannot be excluded with certainty.

Delayed-Action Preparations↗
PubMed1995

Measurement of Lp(a) with a two-step monoclonal competitive sandwich ELISA method.

OBJECTIVE: To evaluate the results of Lipoprotein (a)[Lp(a)] measurements by a competitive two-step monoclonal enzyme-linked immuno sorbent assay method comparing them with those by a conventional ELISA. METHODS: Serum having various isoforms of Lp(a) and purified Lp(a) were assayed using the method described here and commercially available kits. The reference range was determined with the use of 324 normal subjects by means of calculation from Lp(a) results of logarithmic transformation. RESULTS: Our method takes advantage of a competitive reaction between fixed antibody and free antibody to Lp(a), having the detection range up to 1000 mg/L with the lowest detection limit of 2 mg/L. The anti-Lp(a) monoclonal antibody employed in the assay system reacts uniformly with all phenotypes of Lp(a) but showing very low cross-reactivity for plasminogen and LDL. Within-run and between-run precisions were excellent, giving CVs of 2.9 and 4.0% with mean values of 145 and 635 mg/L, respectively. In comparison of the results by our method with those by a polyclonal method (Biopool) or a monoclonal antibody method (Terumo), they correlated well; Y (our method) = 0.99 x (polyclonal method, Biopool) - 1.9, r = 0.994 (n = 60), and Y = 0.94 X(monoclonal method, Terumo) -9.8, r = 0.97 (n = 60), respectively. The reference range was 105.9 +/- 25.4 mg/L, the difference between the sexes was not significant. CONCLUSION: Our method has proven highly accurate and specific. It is applicable with auto analyzer because it does not require such a pre-dilution step as is necessary for Lp(a) determination by conventional ELISA assay. Accordingly, we can conclude that our test method is workable for both clinical laboratories and mass screening.

Antibodies, Monoclonal↗
PubMed1995

Two endothelin receptors (ETA and ETB) expressed on circular smooth muscle cells of guinea pig cecum.

BACKGROUND/AIMS: The functional receptors for endothelin (ET) in colonic smooth muscle are still unknown. This study investigated the expression of ET receptors in isolated circular smooth muscle cells of guinea pig cecum. METHODS: Inhibition of 125I-ET-1 binding was examined using unlabeled ET-1, ET-2, ET-3, sarafotoxin 6c (S6c), and ETA antagonists. Expression of the ET-receptor message was investigated using reverse-transcription polymerase chain reaction. The contractile potency of the ET family and the inhibitory effect of ETA antagonists on ET-1-induced contraction were also investigated. RESULTS: Unlabeled ET-1, ET-2, and ET-3 inhibited the specific binding of 125I-ET-1 in a concentration-dependent manner, but the inhibitory effect of ET-3 was smaller than those of ET-1 and ET-2. At a 10(-6) mol/L concentration of S6c, the specific binding of 125I-ET-1 was 24.7%. S6c had clearly reached maximal inhibition. Abundant polymerase chain reaction products for both the ETA and the ETB message were observed. ET-1 and ET-2 showed similar contractile potency, but ET-3-induced and S6c-induced contractions were significantly less potent than the ET-1-induced contraction. A significant response to S6c was obtained at a concentration as low as 10(-10) mol/L. The ETA antagonists BQ-123 and FR 139317 significantly inhibited ET-1-induced contraction. CONCLUSIONS: The results show a direct contractile effect of ETs on circular smooth muscle of guinea pig cecum and the presence of both ETA- and ETB-receptor subtypes.

Animals↗
PubMed1995

Interaction between atrial natriuretic peptide and vasoactive intestinal peptide in guinea pig cecal smooth muscle.

BACKGROUNDS & AIMS: The role of atrial natriuretic peptide (ANP) in gastrointestinal motility is still unclear. The aim of this study was to investigate the relationship between ANP and vasoactive intestinal peptide (VIP) in guinea pig cecal circular smooth muscle cells. METHODS: The inhibition of 125I-ANP binding or 125I-VIP binding to cecal smooth muscle cells was assessed using unlabeled peptides (i.e., ANP, ANP fragments, VIP, secretin, and peptide histidine isoleucine); the effect of ANP, ANP fragments, and VIP on muscle contraction stimulated by 1 mumol/L carbachol was assessed; and the inhibitory effects of ANP 1-11 on VIP-induced relaxation, ANP 1-11 and VIP 10-28 (a VIP antagonist) on ANP-induced relaxation, and nitric oxide production inhibitors on ANP-induced relaxation were assessed. RESULTS: The specific binding of 125I-ANP was inhibited completely by unlabeled ANP and VIP in a dose-dependent manner but only slightly inhibited by secretin and peptide histidine isoleucine. ANP 1-11 and C-atrial natriuretic factor inhibited the binding of 125I-ANP with a lower affinity than ANP. ANP only partly inhibited 125I-VIP binding. ANP and VIP inhibited 1 mumol/L carbachol-induced contraction in a dose-dependent manner. ANP 1-11 significantly inhibited VIP-induced relaxation. ANP 1-11, VIP 10-28, and NO production inhibitors completely inhibited ANP-induced relaxation. CONCLUSIONS: The results of the study showed that ANP 1-11 antagonized ANP-induced relaxation and that ANP stimulated NO production and subsequently induced relaxation via a receptor to which VIP binds.

Animals↗
PubMed1995

Successful management of infantile hepatic hilar hemangioendothelioma with obstructive jaundice and consumption coagulopathy.

A 4-month-old boy with benign hemangioma of the porta hepatis is described. Obstructive jaundice and consumption coagulopathy developed, which were treated by percutaneous transhepatic drainage (PTHD), without resection of the tumor or bypass surgery. Because of tumor regression, the patient has remained free of symptoms even after the PTHD tube was removed. Because juvenile hemangioma is a benign tumor and occasional spontaneous regression is known to occur (as in our case and other reports), it is suggested that complete resection or bypass surgery is not necessary for juvenile hemangioendothelioma, even with obstructive jaundice, if bile drainage is adequately maintained.

Cholestasis↗
PubMed1995

Pathogenicity of bacteria using a simulated root canal system.

The purpose of this study was to investigate the reliability of an implantation test using Teflon-simulated root canals for evaluating the pathogenicity of root canal bacteria. Models including suspensions of lyophilized strains (Actinomyces israelii, Streptococcus faecalis, and Porphyromonas asaccharolyticus) were implanted in rat subcutaneous tissue for 1 wk, and histological changes were observed. Severe inflammation occurred around the models. Among them, P. asaccharolyticus induced the severest inflammatory response. Further study using P. asaccharolyticus was conducted to compare the implantation test's ability to evaluate pathogenicity with that of an injection test at 1, 2, or 4 wk. Tissue injected with a bacterial suspension showed no clear response through the experimental periods, whereas tissue around implantation sites showed a severe response at 1 wk. However, the inflammatory response subsided at later stages. Consequently, further improvement is needed to investigate pathogenicity for long periods.

Actinomyces↗
PubMed1995

Newly discovered familial juvenile gouty nephropathy in a Japanese family.

Our attention was initially called to 2 young Japanese sisters with gout and renal insufficiency, which led to an investigation of members of their family with similar conditions. One sister, a 26-year-old woman who had suffered from polyuria since infancy, suffered from gout and renal insufficiency. Her younger sister also had a history of polyuria, hyperuricemia, and moderately reduced renal function. Their urinary uric acid levels were reduced but purine enzyme activities in the erythrocytes were normal. A renal biopsy specimen from the younger sister showed severe interstitial fibrosis with tubular atrophy. An investigation of the family revealed an autosomal dominant transmission pattern. We believe these are new familial cases of juvenile gouty nephropathy found in a Japanese family.

Adult↗
PubMed1995

Direct contractile effect of endothelin-1 on isolated circular smooth muscle cells of guinea pig caecum.

Smooth muscle cells isolated from the circular muscle layers of the guinea pig caecum were used to determine whether endothelin-1 (ET-1) can cause contraction by exerting a direct action on smooth muscle cells. In addition, the inhibitory effects of 8-(N,N-diethylamino)-octyl-3,4,5-trimethoxybenzoate hydrochloride (TMB-8), an inhibitor of intracellular Ca2+ release, verapamil, a Ca2+ channel blocker, and removal of extracellular Ca2+ on the ET-1-induced muscle contraction were examined. ET-1 elicited a contractile response of isolated smooth muscle cells in a dose-dependent manner (ED50: 2 nM). TMB-8, verapamil, and removal of extracellular Ca2+ significantly inhibited the contraction produced by ET-1. These results strongly suggest that ET-1 has a direct contractile effect on circular smooth muscle cells of the guinea pig caecum, and that this contraction depends on both intracellular and extracellular Ca2+.

Animals↗
PubMed1995

Functional endothelin A receptor on gastric smooth muscle cells.

Smooth muscle cells isolated from the gastric muscle layers of the guinea pig were used to examine the functional endothelin receptor subtype responsible for gastric smooth muscle contraction by endothelin. Endothelin-1 induced the contraction of these cells in a dose-dependent manner, with an ED50 value of 0.2 nM. Endothelin-3-induced contraction was significantly less than that of endothelin-1. Sarafotoxin 6c (10(-11)-10(-7) M), endothelinB highly selective agonist, did not elicit the contraction of gastric smooth muscle cells. BQ-123, endothelinA selective antagonist, inhibited the contractile response produced by 10(-7) M endothelin-1 in a dose-dependent manner, with an IC50 value of 5 nM. These results strongly suggest that endothelin elicited the contraction of gastric smooth muscle cells via functional endothelinA receptor subtype.

Animals↗
PubMed1995

Small intestinal perforation due to cytomegalovirus infection in patients with non-Hodgkin's lymphoma.

We describe two patients with non-Hodgkin's lymphoma (NHL) who suffered cytomegalovirus (CMV)-related small intestinal perforations during the course of chemotherapy. Surgical specimens from both patients revealed histologic evidence of occlusive vasculitis and tissue destruction caused by CMV-affected cells in the submucosa and muscular walls, that may have played an important role in the pathogenesis of these perforations. Although such intestinal perforations are rare complications in NHL patients, CMV infection should be recognized as a primary etiological factor in acute abdominal crises when treating NHL patients with pharmaceutical agents including steroids. Emergency surgery and the anti-CMV agent, ganciclovir, would improve the prognoses of such patients.

Combined Modality Therapy↗
PubMed1995

Inhibitory effects of cucurbitane triterpenoids on Epstein-Barr virus activation and two-stage carcinogenesis of skin tumor. II.

To search for possible anti-tumor-promoters, we carried out a primary screening of twenty-four 29-nor-cucurbitacin glucosides isolated from the roots of Cayaponia tayuya (Cucurbitaceae) using an in vitro synergistic assay system. Of these glucosides, cayaponosides B (5), B3 (7), D (8), D3b (22) and C2 (23) exhibited significant inhibitory effects on Epstein-Barr virus (EBV) activation induced by the tumor promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA). Furthermore, 5 and 23 exhibited remarkable anti-tumor-promoting effects on mouse skin tumor promotion in an in vivo two-stage carcinogenesis test.

Animals↗
PubMed1995

Immunophenotypes of Reed-Sternberg cells and their variants: a study of 68 cases of Hodgkin's disease.

Utilizing a panel of monoclonal and polyclonal antibodies, routine paraffin sections in 68 cases of Hodgkin's disease were examined for the presence of immunoreactivity in Reed-Sternberg (R-S) and related cells by the avidin-biotin-peroxidase complex (ABC) technique. In 14 cases of lymphocyte-predominant Hodgkin's disease (LPHD), R-S cells and the polyploid lymphocytic and histiocytic (L & H) variants of R-S cells were immunoreactive for L26 and alpha 1-antitrypsin (alpha 1-AT) in 9 (64%) and 6 (43%), respectively, whereas the remaining antibodies were negative or rarely positive against L & H variants of R-S cells. R-S cells in 24 cases of mixed cellularity Hodgkin's disease (MCHD) were positive with alpha 1-AT in 63% of cases, positive with LN3 in 71% of cases and positive for BerH2 in 92% of cases. The lacunar cell type of R-S cells in 19 cases of nodular sclerosing Hodgkin's disease (NSHD) were reactive for alpha 1-AT in all cases, BerH2 in 18 cases (95%), and LN3 in 17 cases (89%). Pleomorphic variant of R-S cells in 11 cases of lymphocyte depleted Hodgkin's disease (LDHD) showed reactivity with alpha 1-AT in 9 cases (82%), BerH2 in 6 cases (55%), and LN3 in 9 cases (82%). The incidence of L26 in R-S cells was higher in LPHD than in other three subtypes, whereas the immunohistochemical finding of alpha 1-AT had reverse relevance to the result of L26. The incidence of BerH2 in MCHD and NSHD was higher than that of this antibody in the whole of Hodgkin's disease. R-S cells in NSHD and LDHD were highly positive to LN3, and detection rate of these two types was higher than that in the whole of Hodgkin's disease. No cases showed immunoreactivity with anti-T-cell antibodies (CD3, UCHL1 and DFT1), a marker for natural killer cell (Leu7), and a marker for interdigitating reticulum cell (S-100 protein). These results suggest that correlation between predominant staining pattern and R-S cells and variants thereof in each histological subtype of Hodgkin's disease are as follows: LPHD shows L26+, alpha 1-AT-, BerH2-; MCHD and NSHD show L26-, alpha 1-AT+, BerH2+; and LDHD shows L26-, alpha 1-AT+, BerH2+ or L26+, alpha 1-AT+, BerH2-.

Antibodies, Monoclonal↗