Biomedical subjects

H Kato

Publications and source records attributed to H Kato.

At least 415 records · Page 23Linked to original sources

PubMed2000

Vascularised fibular grafts. An experience of 102 patients.

The results and complications of 104 vascularised fibular grafts in 102 patients are presented. Bony union was ultimately achieved in 97 patients, with primary union in 84 (84%). The mean time to union was 15.5 weeks (8 to 40). In 13 patients, primary union was achieved at one end of the fibula and secondary union at the other end. In these patients, the mean time to union was 31.1 weeks (24 to 40). Five patients failed to achieve union, with a resultant pseudarthrosis (3 patients) or amputation (2 patients). There were various complications. Immediate thrombosis occurred in 14 cases. In two of 23 patients with osteomyelitis, infection recurred at two and six months after surgery, respectively. Both patients had active osteomyelitis less than one month before the operation. Bony infection occurred in a patient with a synovial sarcoma of the forearm one year after surgery. In 15 patients, 19 fractures of the fibular graft occurred after bony union, all except one within one year after union. In patients in whom an external fixator had been used, fracture occurred soon after its removal. Union was difficult to achieve in cases of congenital pseudarthrosis of the tibia. Appropriate alignment of the fibular graft is an important factor in preventing stress fracture. The vascularised fibula should be protected during the first year after union. Postoperative complications at the donor site included transient palsy of the superficial peroneal nerve in three patients, contracture of flexor hallucis longus in two and valgus deformity of the ankle in three. Vascularised fibular grafts are useful in the reconstruction of massive bony defects. We believe that meticulous preoperative planning, including choosing which vessels to select in the recipient and the type of fixation devices to use, and care in the introduction of the vascularised fibula, can improve the results and prevent complications.

Adolescent↗

PubMed2000

Clinical and histologic features of chronic hepatitis C virus infection after blood transfusion in Japanese children.

OBJECTIVE: To characterize the clinical and histologic features of chronic hepatitis C virus (HCV) infection after blood transfusion in Japanese children. STUDY DESIGN: We studied 231 children with a history of blood product transfusion. Patients were divided into two groups: 116 patients with a history of malignant disease (group 1), 115 patients who had undergone open heart surgery (group 2). We examined changes in serum alanine aminotransferase (ALT) activity and HCV markers, and patients' clinical course. Moreover, in 38 patients in whom the time of HCV infection could be defined, we examined liver histology. RESULTS: The proportions of patients in each group who were anti-HCV-positive were 35 out of 116 (30%) and 20 out of 115 (17%), respectively. Of the anti-HCV-positive patients, the proportions of HCV RNA-positive patients in each group were 30 out of 35 (86%) and 12 out of 20 (60%), respectively. Levels of ALT activity in patients with HCV infection varied widely for several years after blood transfusion; thereafter ALT activity fell to <100 IU/L in 2 groups. Serum ALT activity in patients who were HCV RNA-negative became normal. With regard to liver histology, there were no differences in the grade of necroinflammation or stage of fibrosis in patients with different durations of infection or when patients were analyzed according to the presence or absence of malignant disease. Patients mostly had grade 2-4 inflammation and stage 1-2 fibrosis. Thus, chronic hepatitis C was a morphologically mild disease in most children in this study. CONCLUSIONS: Sixty percent to 80% of children with HCV infection in this study developed chronic hepatitis C. However, examination of liver histology findings in children with chronic hepatitis C showed only mild changes.

Adolescent↗

PubMed2000

Gene expression of the three members of hepatocyte nuclear factor-3 is differentially regulated by nutritional and hormonal factors.

Hepatocyte nuclear factor-3 (HNF-3) belongs to a large family of forkhead transcription factors and is made up of three members (HNF-3alpha, -3beta and -3gamma). It has been shown that HNF-3 regulates a number of metabolically important genes. However, the mechanisms underlying this regulation of HNF-3 activity by hormones and nutrition have not yet been well elucidated. In attempting to explore the regulation of gene expression of HNF-3 members by physiological status, we analyzed the effects of insulin, dexamethasone and protein malnutrition on the hepatic mRNA level of each member. Male Wistar rats were fed on a 12% casein diet, 12% gluten diet (deficient in lysine and threonine) or a protein-free diet for 1 week. The protein-free diet and gluten diet caused a 3. 7-fold increase in HNF-3g mRNA in the liver and did not affect the mRNA level of either HNF-3alpha or HNF-3beta. Daily administration of dexamethasone caused the mRNA levels of HNF-3alpha and HNF-3beta to increase (2.3- and 1.4-fold, respectively), but had no effect on the HNF-3gamma mRNA level. In diabetic rats that had been injected with streptozotocin, an elevation of the hepatic mRNA levels of HNF-3beta and HNF-3gamma was observed (1.6-and 1.9-fold, respectively). Insulin replacement in the diabetic rats decreased both mRNA levels in a dose-dependent manner. HNF-3alpha mRNA was not affected by insulin status. These results show that the genes of the three members of the HNF-3 family respond differently to hormonal and nutritional factors suggesting that the activities of HNF-3 members are regulated, at least in part, by the levels of their gene expression.

Animals↗

PubMed2000

A study of attached and oriented human periodontal ligament cells to periodontally diseased cementum and dentin after demineralizing with neutral and low pH etching solution.

BACKGROUND: This study aimed to evaluate quantitatively the migrated, attached, and oriented human periodontal ligament cells (HPLC) to periodontally diseased cementum and dentin after demineralization with low and neutral pH etching solution. METHODS: Human teeth, extracted due to periodontal diseases, were scaled and root planed so that cementum remained on one longitudinal half of the root and dentin was exposed on the other half. Forty root slices of 200 microm thickness, obtained from the mid-third of these roots, were divided into four groups: group 1, demineralized with a saturated solution of citric acid (pH 1.20); group 2, with 24% EDTA (pH 7.04); group 3, with tetracycline HCl 100 mg/ml (pH 2.00); and group 4, only scaled and root planed (control). Root slices were placed over the confluent HPLC in 35 mm culture dishes and incubated. Phase contrast microscopic photographs of attached and oriented refractile HPLC to root surfaces were taken at days 1, 3, and 7. Quantitative analysis of attached and oriented HPLC from these photographs was done using special software. RESULTS: The results showed no significant difference in the attachment and orientation index of HPLC to cementum compared to dentin in any method of demineralization at each time point (P >0.05), although there was a significantly higher cell attachment and orientation index to demineralized dentin with EDTA and citric acid than to non-etched dentin and to all 3 demineralized cementum surfaces compared to non-etched cementum (P<0.05). CONCLUSIONS: EDTA and citric acid demineralization may enhance HPLC attachment and orientation to the root surface, and it is not always necessary to remove excessive cementum when the demineralizing procedure is used.

Cell Adhesion↗

PubMed2000

Riedel's lobe of the liver evaluated by multiple imaging modalities.

An 81-year-old Japanese woman visited our hospital because of abdominal discomfort. Physical examination revealed that she had an abdominal mass. A combination of ultrasonography, computed tomography, magnetic resonance imaging (MRI), and hepatic asialoglycoprotein scintigraphy was utilized to make a diagnosis. We found that she had a downward elongated hepatic lobe or Riedel's lobe which did not appear to be common in our district. The prevalence of Riedel's lobe in the Asian population has not been studied. Furthermore, this is the first report that describes the MRI and hepatic asialoglycoprotein scintigraphy features of Riedel's lobe of the liver.

Abdominal Pain↗

PubMed2000

[A case of common variable immunodeficiency with intractable diarrhea and the functional disorder of renal tubules].

We report a case of a 31-year-old woman with common variable immunodeficiency (CVID) complicated with intractable diarrhea and the functional disorder of renal tubules. The patient became hypogammaglobulinemic after she suffered from measles at 6 years of age. She also suffered from lupus-like syndrome at 7 years of age. The complete remission was obtained by glucocorticosteroid treatment. An intravenous immunoglobulin replacement therapy was introduced at 11 years of age, since then her general condition was stable for more than 20 years. When she was 29 years old, she suffered from generalized malaise, anorexia with body weight loss, and numbness of face. The intractable diarrhea as protein loosing syndrome, and the severe abnormality of electrolyte balance with metabolic acidosis as the functional disorder of renal tubules were found. Her condition was not improved by the electrolytes or alkali replacement therapy. She was admitted for further evaluation and treatment. The intractable diarrhea and the functional disorder of renal tubules were dramatically improved after absolute restriction of food intake under hyperalimentation. When she began to take food, the symptom and sign became worse again. The interstitial nephritis and nonspecific inflammation of intestine were found by the tissue biopsy. The most characteristic finding was the infiltration of lymphocytes (predominantly CD 8 + T lymphocytes) in both intestinal mucosa and renal interstitium. The introduction of glucocorticosteroids improved her general condition and biochemical findings. This CVID case is complicated with intractable diarrhea and the functional disorder of renal tubules which is associated with the infiltration of CD 8 + lymphocytes in intestine and kidney. We consider that such case is very rare and valuable to report.

Adult↗

PubMed2000

Mortality among persons with a history of Kawasaki disease in Japan: existence of cardiac sequelae elevated the mortality.

OBJECTIVE: To clarify whether patients with Kawasaki disease have a higher death rate than the age-matched healthy population after the disease occurrence. STUDY DESIGN: Between July 1982 and December 1992, 52 collaborating hospitals collected data on all patients having a new definite diagnosis of Kawasaki disease. Patients were followed until December 31, 1997, or death. The expected number of deaths was calculated from Japanese vital statistics data and compared with the observed number. RESULTS: Of 6576 patients enrolled, 25 (19 males and 6 females) died. The standardized mortality ratio (SMR) was 1.35. In spite of the high SMRs during acute phase, the mortality rate was not high after the acute phase for all patients. Although the SMR after the acute phase was 0.76 for those without cardiac sequelae, 6 males (no females) with cardiac sequelae died during this period and the SMR for the male group with cardiac sequelae was 2.77. CONCLUSION: The mortality rate among males with cardiac sequelae due to Kawasaki disease was 2.8 times as high as in general population, whereas mortality rates for females with the sequelae and both males and females without sequelae were not elevated.

Adolescent↗

PubMed2000

Molecular analysis of multidrug resistance in feline lymphoma cells.

OBJECTIVE: To evaluate the mechanism of multidrug resistance in feline lymphoma cell lines. SAMPLE POPULATION: A feline lymphoma cell line (FT-1) and its adriamycin (ADM)-resistant subline (FT-1/ADM). PROCEDURES: The FT-1 cell line was cultivated in the presence of a gradually increasing concentration of ADM to generate its ADM-resistant subline (FT-1/ADM). Susceptibility of cells from the parental FT-1 cell line and the FT-1/ADM subline to antineoplastic drugs was determined. From the complementary DNA (cDNA) template of FT-1/ADM cells, feline MDR1 cDNA was amplified by use of polymerase chain reaction (PCR) and sequenced. Reverse transcription (RT)-PCR and Western blot analyses were performed to assess expression of the MDR1 gene and P-glycoprotein (P-gp) in FT-1/ADM cells, compared with that in FT-1 cells. RESULTS: A drug sensitivity assay revealed that FT-1/ADM cells were much more resistant to ADM and vincristine than the parental FT-1 cells. The feline MDR7 cDNA amplified by use of PCR was 3,489 base pairs long, corresponding to approximately 90% of the whole open reading frame of human MDR1 cDNA; its amino acid sequence was 91.5, 87.0, and 79.4% identical to that of human MDR1, mouse mdr1a, and mdr1b cDNA, respectively. By RT-PCR analysis, expression of MDR1 messenger RNA was clearly detected in FT-1/ADM cells but not in the parental FT-1 cells. Western blot analysis also revealed the expression of P-gp encoded by the MDR1 gene in FT-1/ADM cells but not in FT-1 cells. CONCLUSIONS: The basic structure of the feline MDR1 gene was essentially the same as that of multidrug-resistance genes of other species. Expression of P-gp appeared to be one of the mechanisms responsible for the development of multidrug resistance in feline lymphoma cell lines in vitro.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2000

PSK and OK-432-induced immunomodulation of inducible nitric oxide (NO) synthase gene expression in mouse peritoneal polymorphonuclear leukocytes and NO-mediated cytotoxicity.

We investigated whether PSK (a polysaccharide from the mycelia of Coriolus versicolor) or OK-432 (a streptococcal preparation) can up-regulate inducible nitric oxide synthase (iNOS) gene expression and nitric oxide (NO) production in mouse peritoneal polymorphonuclear leukocytes (PMNs). Six hrs after intraperitoneal injection of mice with PSK (2,500 microg/mouse) or OK-432 (100 microg/mouse), mouse peritoneal PMNs were restimulated with PSK (500 microg/ml) or OK-432 (10 microg/ml) plus 100 U/ml of mouse interferon-gamma (IFN-gamma) in vitro. Northern blot analysis showed strong synergism between both PSK and OK-432 and IFN-gamma for the induction of iNOS gene expression. NO production by PMNs was increased up to 20 microM (2 microM/10(6) PMNs/24 hrs) as measured by the Griess reagent method when PMNs were restimulated with PSK or OK-432 plus IFN-gamma for 24 hrs, although tumor cell killing was not detected. NO concentrations of more than 80 microM were required for P815 tumor cell killing. These results suggest that PMNs produce NO after stimulation with PSK or OK-432 in combination with IFN-gamma and may regulate the immune system in vivo, although the NO production induced by these agents is insufficient for tumor cell killing in vitro.

Adjuvants, Immunologic↗

PubMed2000

Midkine expression in Reed-Sternberg cells of Hodgkin's disease.

Midkine (MK) was originally cloned as a product of a retinoic acid-responsive gene. The rationale for studying MK expression is based on previous reports showing that it transforms 3T3 cells, and that it acts as an autocrine growth factor in Wilm's tumors, and that its overexpression has been associated with worse outcome in bladder carcinoma. Besides bladder carcinoma, its expression was reported in various solid tumors. We investigated the expression of MK protein and/or MK gene in biopsied specimens from 40 patients with primary malignant lymphoma, 21 with Hodgkin's disease (HD) and 19 with non-Hodgkin's lymphoma (NHL). Reed-Sternberg (R-S) cells were stained positive in 10 of 16 HD cases evaluated by immunohistochemical method, whereas 18 of 19 NHL cases did not stain, and one B-cell NHL stained weakly positive. Immunostaining analysis was extended to established cell lines and to normal lymphocytes with or without lectin stimulation or with EB virus transformation. Among hematopoietic cells examined, erythro- or megakaryoblastic leukemia cell lines (K562, MEG-01 and UT7) were positive, while normal lymphocytes (except the EB virus-transformed one) and most myeloid and lymphoid cell lines (except Raji cells) were negative. On the contrary, solid tumor cell lines showed high and strongly positive staining including cell lines derived from of lung gastric, colon, and a pancreatic cancer. Using semi-quantitative reverse transcription polymerase chain reaction (RT-PCR), which is suitable for the detection of weakly expressed mRNA, the relative ratio of MK mRNA to beta-actin mRNA of samples was measured and compared in cases where RNA was available. The mean values of relative ratio (MK/beta-actin) of HD were almost twice as those of NHL samples, peripheral blood T cells, and spleen B cells. Our findings showed that MK is expressed in Reed-Sternberg cells of HD, and that MK might play a role in the pathogenesis of HD.

Animals↗

PubMed2000

Reduced or absent expression and codon 201Gly/Arg polymorphism of DCC gene in rhabdomyosarcoma and Ewing's sarcoma/PNET family.

Genetic alterations occurring in various chromosomes have been described in many human tumors. The DCC gene was originally identified in colorectal cancer and was reported as a tumor suppressor gene that might be related to tumor metastasis. We investigated 10 cell lines and 15 fresh tumors of childhood rhabdomyosarcoma, 7 cell lines of Ewing's sarcoma, and 4 cell lines of primitive neuroectodermal tumor (PNET) for the expression and mutation of DCC gene by RT-PCR analysis and PCR-single stranded conformation polymorphism (SSCP) analysis. Twenty-five pairs of primers were used for PCR-SSCP. Six of ten (60%) cell lines of rhabdomyosarcoma and 3 of 7 (43%) cell lines of Ewing's sarcoma showed reduced or absent expression of DCC gene. There was no mobility shift within 24 exons by SSCP analysis, although 3 types of polymorphism were found at codon 201 in exon 3. Direct sequencing of different bands showed types I, II, and I/II representative of codon 201Gly, codon 201Arg, and codon 201Gly/Arg, respectively. The proportion of type I between fresh rhabdomyosarcoma and normal controls was not significant. Our results suggested that the inactivation of DCC gene may play a role in the pathogenesis of a subset of rhabdomyosarcoma and Ewing's sarcoma.

Adolescent↗

PubMed2000

A case of small polypoid esophageal carcinoma with multidirectional differentiation, including neuroendocrine, squamous, ciliated glandular, and sarcomatous components.

A small composite esophageal carcinoma measuring 1.5 x 1.4 x 1.0 cm is described. The tumor had a polypoid elevation with a superficial extension. Histologic examination revealed invasion of the submucosal layer and multidirectional differentiation, including neuroendocrine, squamous, ciliated glandular, and sarcomatous components. The neuroendocrine component was strongly positive for chromogranin and formed the bulk of the polypoid tumor. The squamous cell carcinoma exhibited a superficial extension. The adenocarcinoma was located in a small region of the tumor and contained ciliated glandular cells. The spindle cell sarcomatous component, which was positive for alpha-smooth muscle actin and negative for cytokeratin, exhibited no specific mesenchymal differentiation. Each component was found in 60%, 10%, 5%, and 25% of the tumor, respectively. Cases of small composite esophageal carcinoma containing various carcinomatous and sarcomatous components are extremely rare.

Actins↗

PubMed2000

[A case of rhabdomyolysis with water intoxication confirmed by muscle biopsy].

A 32-year-old woman with chronic schizophrenia who took 8-10 liters of water for three years due to thirsty, admitted to our hospital because of convulsion and muscle weakness. Neurological finding on admission showed a mild disturbance of consciousness, moderate proximal muscle weakness, and muscle pain. Laboratory examination revealed marked serum hyponatremia(102 mEq/l) and high value of creatin kinase (1,259 IU/l). The level of creatin kinase reached a peak(39,700 IU/l) at the 5th hospital day. An analysis of the muscle biopsy specimen showed necrotic muscle fibers and opaque fibers, that was compatible with rhabdomyolysis. T 2 weighted magnetic resonance imaging of the brain showed a transient high signals in bilateral putamen but not in pons. She was diagnosed to have rhabdomyolysis due to water intoxication. The present case is the first rhabdomyolysis in Japan that was confirmed by muscle biopsy at an acute stage of water intoxication related with schizophrenia.

Adult↗

PubMed2000

Three-dimensional helical computed tomographic angiography in neonates and infants with complex congenital heart disease.

BACKGROUND: For the clinical management of patients with complex congenital heart disease (CHD), accurate evaluation of their morphologic conditions is critical. Three-dimensional (3D) helical computed tomography (CT) angiography has been used to assess the vascular system in adult patients; the indication for complex CHD, especially in the neonatal period, has not yet been defined. Therefore the purposes of our study were to determine the quality and limitations of current 3D helical CT angiography for neonates and infants with complex CHD and to assess the clinical utility of this technique. METHODS AND RESULTS: 3D helical CT angiography was performed in 17 patients with various types of complex CHD. Their median age was 41 days (range 3 days to 9 months), and mean body weight was 3.6 kg (range 2.2 to 8.5 kg). All 3D images were produced with the 3D reconstruction algorithm of shaded-surface display. Oral sedation was required in only 4 infants during the procedure. 3D helical CT angiography clearly demonstrated the shape and spatial relation of great arteries, proximal branch pulmonary arteries, anomalous pulmonary venous connections, the patent ductus arteriosus, and a shunt. The 3D information of extracardiac morphologic characteristics and 3D anatomic relation of each extracardiac structure were easily recognized by this imaging process. However, intracardiac structure could not be visualized because of blurred and/or unclear edges of the ventricular wall caused by respiratory movement. CONCLUSIONS: 3D helical CT angiography represents an important additional diagnostic tool and may become an alternative method to angiography or other noninvasive techniques used in the evaluation of extracardiac anomalies in neonates and infants with complex CHD.

Adult↗

PubMed2000

Regional cerebral blood flow after status epilepticus.

Two patients with status epilepticus due to specific conditions were examined using MRI and stable Xe/CT CBF. [Case 1] A 30-year-old woman developed a grand mal seizure during delivery. She was comatose, and MRI revealed abnormal high intensity areas bilateral basal ganglia, compatible with eclampsia. Regional CBF was decreased in bilateral occipital lobes and right basal ganglia. Six days after onset. Regional gray matter flow was increased, especially in the thalami and basal ganglia. [Case 2] The patient is a 31-year-old male diagnosed with temporal lobe epilepsy since 10 years. At the onset, he had a prolonged right hemiconvulsion followed by generalized tonic-clonic convulsion. MRI 13 days after onset showed left hemispheric edematous swelling of gray matter. Stable Xe/CT 3 weeks after onset demonstrated increased cortical CBF corresponding to edematous area. The results suggested that regional CBF decreased immediately after status epilepticus and then increased for 1-3 weeks in the interictal period. We speculate that the energy debt incurred during prolonged seizure causes relative ischemic condition in the neurons, with the increase in CBF resulting from accelerated energy production for a long period.

Adult↗

PubMed2000

[Congenital thrombophilia caused by protein C deficiency].

To clarify the prevalence of protein C deficiency in patients with cardiovascular problems, we identified 54 patients with protein C deficiency by screening approximately 26,800 patients. The observed prevalence of protein C deficiency was 1 in 500. From the results of genetic analysis of 67 Japanese families with protein C deficiency, the recurrent defects of Phe139Val, Arg169Trp, Val297Met, Met364Ile substitutions and a G8857 deletion were accounting 49% of Japanese families with protein C deficiency. The defects including Phe139Val and Met364Ile substitutions and a G8857 deletion were only found in Japanese subjects and seemed to be a founder effect. Protein C deficiency is associated with a predisposition to venous thrombosis. It is not clear whether the deficiency is involved in arterial occlusion. We identified 34 patients with protein C deficiency manifested 45 episodes of arterial occlusive disease. We compared the onset age of arterial occlusive disease between patients with protein C deficiency and a group of patients with normal protein C levels. We found the early onset of acute myocardial infarction and atherothrombotic cerebral infarction in patients with protein C deficiency. Thus, our study suggests that congenital protein C deficiency contributes to earlier onset of arterial occlusive diseases in Japanese subjects.

Arterial Occlusive Diseases↗

PubMed2000

[Bronchofiberscopy].

New diagnostic modalities have been used in conjunction with endoscopy for early detection of lung cancer. Videoendoscope is routinely used instead of fiberoptic bronchoscope. Fluorescence diagnosis has been proved to be useful in detecting subtle lesions which might be invisible by conventional endoscopy in central airway. Also, a number of small peripheral lesions has increased by the helical CT. CT guided transbronchial lung as well as needle cytology are indicated for definitive diagnosis of such lesions. Endobronchial Ultrasonography is employed to evaluate the depth of cancer invasion of the bronchus and lymph node swelling around the bronchus. It should be helpful in staging of lung cancer and selecting therapy.

Bronchoscopy↗

PubMed2000

[Molecular biological diagnosis].

Biological behavior of lung cancer was evaluated by basic study. Malignancy Associated Change is the concept that the nuclear features of normal cells in the vicinity of cancer show subtle morphological difference from those of healthy individuals. The difference was recognized by high resolution cytometry and the expression of MAC cells was correlated with the degree of abnormality of chest diseases. Comparative genomic hybridization and fluorescence in situ hybridization were performed to investigate genetic abnormality of. Multiple genetic abnormalities and chromosomal instability showed poor prognosis. Two dimensional electrophoresis was employed to detect the expression of the specific protein of lung cancer. TAO2 was proved to be specific to well differentiated adenocarcinoma. Also, metabolic analysis will be employed for cell analysis.

Biomarkers, Tumor↗