Human factor VIII inhibitor alloantibodies with a C2 epitope inhibit factor Xa-catalyzed factor VIII activation: a new anti-factor VIII inhibitory mechanism

Factor VIII (FVIII) inhibitor alloantibodies react with the A2, C2, or A3-CI domains of FVIII and inactivate FVIII activity. We recently demonstrated that an anti-C2 monoclonal antibody with a Val2248-Gly2285 epitope, inhibited factor Xa (FXa)-catalyzed FVIII activation, and that a FXa binding site for FVIII was located within residues Thr2253-Gln2270. In this study, we investigated whether anti-C2 alloantibodies inhibit FXa-catalyzed FVIII activation. Anti-C2 alloantibodies from four patients inhibited FVIII activation by FXa in one-stage clotting assay. Furthermore, analysis by SDS-PAGE showed that all alloantibodies inhibited FVIII proteolytic cleavage by FXa independently of phospholipid. To confirm direct inhibition of FVIII and FXa interaction, we examined the effect of alloantibodies on FVIII binding to anhydro-FXa, a catalytically inactive FXa, in ELISA. All alloantibodies and C2-affinity purified F(ab)'2 preparations inhibited FVIII binding to anhydro-FXa dose-dependently. Our results revealed a new inhibitory mechanism of FVIII, mediated by inhibition of FXa in the presence of anti-C2 alloantibodies.     

Evaluation of intractable diseases

OBJECTIVE: The aim of this study was to determine priorities for specific intractable disease from the viewpoint of countermeasures. METHODS: A significance evaluation to provide a priority framework for intractable disease was performed with a questionnaire distributed to the staff of preventive medicine and public health departments of medical schools in Japan. To determine the actual conditions of these intractable diseases question were directed at the chairmen of individual clinical study groups. The priority to be assigned countermeasures for such diseases was obtained from the two questionnaires. RESULTS: When the 4 factors "rare nature of diseases," "level of clarity of causes and pathology," "unestablished curative treatment", and "influence on daily life" were evaluated using 100 point as a full score, the mean scores were 14.5, 27.1, 28.5 and 29.9 points, respectively. In attaching importance to the various items, regarding the "rare nature of disease" the elements of "few patients nationwide" and "few specialist doctors nationwide" proved important; for the "level of clarity of causes and pathology," this was the case for the elements of "unclear triggering mechanism" and "diagnostic criteria not established." With the "unestablished curative treatment," the "no efficacious treatment available" and "low 5-year survival rate elements were important; and with the factor of "influence on daily life," the two most significant were "high proportion of patients needing assistance in daily life" and "high percentage of patients impeded from attending school or obtaining a job (playing a role in society)". CONCLUSION: When the priority among the 118 intractable diseases was evaluated by combining the overall results of the questionnaire survey with preventive medicine and public health staffs, and actual condition data from survey investigation of the intractable diseases among chairmen of clinical study groups, it was suggested that some intractable diseases whose medical expenses are covered by the medical aid program have a low ranking.     

Monoamine oxidase-B activity in alcohol withdrawal of smokers: is there any relationship with aggressiveness?

There is a considerable inconsistency in terms of the association between alcoholism and alterations in monoamine oxidase (MAO) activity. The main objectives of this study were to investigate the changes in platelet MAO-B activity throughout the alcohol withdrawal period and whether or not MAO-B activity differed between patients with high- and low-aggression tendency. We assayed platelet MAO-B levels spectrophotometrically in 22 male inpatients with alcohol dependence in their first and fourth weeks of withdrawal and in 20 healthy controls. Patients were divided into two high- and low-aggression subgroups according to scores obtained in a Brown-Goodwin Assessment for Life History of Aggression. Our data revealed that the significantly lower platelet MAO-B activity observed during the first week of alcohol withdrawal in patients, compared to controls, did not continue in the fourth week, and that there was no relationship between aggressiveness and MAO activity. These results suggest that low platelet MAO activity may be a state marker of alcohol withdrawal period or a result of high alcohol consumption rather than a trait marker of alcoholism.     

Embolization of uterine artery in terminal stage cervical cancers

Ligation of the hypogastric artery has been a standard and effective procedure in controlling massive bleeding in advanced cervical carcinoma. The authors wanted to demonstrate the selective use of embolization of hypogastric or uterine artery to achieve the same end result--the stoppage of vaginal bleeding. In a number of cases, surgical approach may not be appropriate either because of the critically ill patient or because of the highly deformed pelvic anatomy due to radiotherapy or to the recurrence of cancerous tissue. As an alternative therapy, we used selective embolization of the uterine artery in eight patients. In all the patients, embolization served to control bleeding. As the bleeding was brought under control, a gradual recovery of the patient was generally observed. The most common side-effect was temporary severe pain related to ischemia of tumoral tissue. Embolization may be regarded as an effective procedure, which can be used to control massive bleeding in selected cervical cancer patients.     

Microsatellite instability and immunohistochemical analysis of MLH1 and MSH2 in normal endometrium, endometrial hyperplasia and endometrial cancer from a hereditary nonpolyposis colorectal cancer patient

Hereditary nonpolyposis colorectal cancer (HNPCC)-related endometrial cancer is associated with mutations in DNA mismatch repair genes. However, chronological changes of these genes in the endometrium have not been studied in women from HNPCC families. Tissue samples of normal endometrium, endometrial hyperplasia without atypia and endometrial cancer were collected at different times from a 41-year-old Japanese woman with a family history of HNPCC. Combined microsatellite instability (MSI) and immunohistochemical analysis of MLH1 and MSH2 predicted the presence of a mutation in MSH2 when she had endometrial hyperplasia without atypia 7 months before the diagnosis of endometrial cancer. Endometrial hyperplasia without atypia may indicate an early development of endometrial cancer in women from HNPCC families.     

Detection of sentinel lymphatic region with activated carbon particles in lymph node dissection for colorectal cancer

Sentinel node navigation surgery (SNNS) for gastrointestinal cancer has been examined using various methods, but the SN concept has not been established. For 18 patients who had colorectal cancer without macroscopic nodal metastases, we had attempted to detect sentinel lymph nodes (SNs) with activated carbon particles and investigate the existence of nodal metastases histologically. SNs were detected in 17 of 18 patients. Thus activated carbon particles are a useful tracer for SN detection. Three patients had microscopic nodal metastases, and two had nodal metastases in SNs. Although the remaining patient was a false negative case which had nodal metastases in non-SNs only, the nodal metastases were within the sentinel lymphatic region (SLR) which includes SNs. It is considered possible to safely perform minimally invasive lymphadenectomy for colorectal cancer without macroscopic nodal metastases, by means of SLR dissection using activated carbon particles.     

Analysis of effect of dextran sulfate on cancer cells

Peritoneal recurrence is one of the critical problems that occurs after surgery for gastrointestinal cancers. Since no curative treatment has been established for peritoneal recurrence, many efforts have been made to develop an effective method for preventing such recurrence. We focused on dextran sulfate, an anti-cell-adherence agent, to prevent peritoneal metastasis. Our previous studies in vitro and in vivo clarified that dextran sulfate prevents cancer cells from adhering to plastic flasks and the abdominal wall. In this study, we investigated the effects of dextran sulfate on cancer cells from the viewpoint of the cell cycle. Changes in gene expression caused by dextran sulfate were analyzed by cDNA microarrays. Analysis by cDNA microarray revealed the decreased expression of the genes essential to the progression of G1 and S phases. Our results indicate that dextran sulfate suppresses progression of the cell cycle as well as cell adhesion, suggesting that dextran sulfate could be used as an antimetastatic agent. Anti-cell-adherence agents with such mechanisms of action could be effective drugs for treatment during and after operation to prevent peritoneal metastases induced by surgical operation.     

Gastric cancer with multiple liver metastases,which responded significantly to oral administration of TS-1 following intravenous FMP therapy under hospitalization

TS-1, a novel oral formation of 5-fluorouracil that consists of 1 M tegafur (FT), 0.4 M gimeracil and 1 M otacil potassium, was reported to achieve a relatively high response rate of 49% in patients with advanced gastric cancer in a late phase II study. We report a case of inoperable gastric cancer with multiple liver metastases, which responded significantly to the short-term administration of TS-1 following intravenous FMP therapy. A 79-year-old man, who had nothing of note in his past or family history, presented with multiple liver tumors and type 3 gastric tumor. His diagnosis was inoperable gastric cancer with liver metastases, and he underwent outpatient treatment of oral administration of TS-1, following FMP therapy under hospitalization. The main and metastatic lesions shrunk dramatically with the two courses of the chemotherapy. There were no noticeable adverse effects. QOL has been maintained and the patient remains in good condition. TS-1 can be considered well-tolerable and quite effective for inoperable gastric cancer, especially if preceding therapy with 5-FU shows significant efficacy. TS-1 may therefore be a new candidate as a first line drug in outpatient cancer treatment.     

Chemoprevention of 2-amino-1-methyl-6-phenylimidazo- [4,5-b]pyridine-induced colon carcinogenesis by 1-O-hexyl-2,3,5-trimethylhydroquinone after initiation with 1,2-dimethylhydrazine in F344 rats

The aim of this study is to investigate the chemopreventive effects of the synthetic phenolic antioxidant 1-O-hexyl-2,3, 5-trimethylhydroquinone (HTHQ) on 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-associated colon carcinogenesis in rats after initiation with 1,2-dimethylhydrazine (DMH) in male F344 rats. Groups of 20-22, 6-week-old male F344 rats were given four subcutaneous injections of 40 mg/kg body wt of DMH during the initial 4 weeks. They were then maintained on powdered basal diet containing 0.03% PhIP alone, PhIP together with 0.5 or 0.125% HTHQ, 0.5 or 0.125% HTHQ alone or basal diet for 32 weeks. A small number (1.1 +/- 1.1/rat) of colon tumors were induced by DMH treatment alone. After initiation with DMH, the number of colon tumors was greatly increased to 8.3 +/- 5.6 by the administration of PhIP. Additional treatment with HTHQ dose-dependently decreased the multiplicity of colon adenocarcinomas to 4.9 +/- 2.8 and 2.6 +/- 1.4 with 0.125 and 0.5%, respectively. This treatment similarly reduced atypical hyperplasias of the ventral prostate. Furthermore, HTHQ significantly reduced the multiplicity of duodenal adenocarcinomas induced by DMH + PhIP or DMH alone. Immunohistochemically, HTHQ was revealed to suppress PhIP-DNA adduct formation in the epithelial cells of the colon and prostate in a separate 2 weeks experiment. The present results clearly showed that HTHQ has chemopreventive potential for PhIP-associated colon and prostate carcinogenesis. The observed inhibition may largely be due to interference with PhIP-DNA adduct formation. In addition, HTHQ has been demonstrated to inhibit duodenal carcinogenesis in the post-initiation stage.     

Demyelination associated with HSV-1-induced facial paralysis

In 1995, we developed an animal model of transient homolateral facial nerve paralysis by inoculating Herpes simplex virus type 1 (HSV-1) into the auricle of mice. This study examined the mechanism of facial nerve paralysis in this model histopathologically. Using the immunofluorescence technique with anti-HSV-1 antibody, the time course of viral spread and the site of viral replication were investigated over the entire course of the facial nerve. Furthermore, viral replication and nerve degeneration at the site of viral replication were observed by electron microscopy. On the 7th day after inoculation, facial paralysis was observed in more than 60% of mice. Immunofluorescence study revealed HSV-1 in the geniculate ganglion, the descending root, and the facial nucleus at this stage. On the 9th day, the descending root in the sections stained with osmium looked pale, because prominent demyelination had occurred in this region; electron micrographs showed many degenerated oligodendrocytes and large naked axons. In contrast, the facial nucleus neurons showed no remarkable degeneration, despite HSV-1 particles in their cytoplasm. From these findings, we concluded that facial nerve paralysis in this model is caused mainly by facial nerve demyelination in the descending root.