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Biomedical subjects

H Kawabata

Publications and source records attributed to H Kawabata.

At least 127 records · Page 7Linked to original sources
PubMed1994

In vitro antibiotic susceptibilities of Borrelia isolates from erythema migrans lesion of Lyme disease patients in Japan.

Antibiotic susceptibilities of twelve borrelial isolates from skin of patients with erythema migrans (EM) and ticks (Ixodes persulcatus and I. ovatus) in Japan were examined by in vitro microdilution MIC method and macrodilution MBC method. Nine EM isolates and 3 tick isolates were susceptible to amoxicillin, erythromycin, and minocycline. MICs for Japanese isolates were 0.038-0.30 microgram/ml, < 0.012 microgram/ml, and < 0.012-0.05 microgram/ml, respectively. MBCs were as follows: 0.038-0.88 microgram/ml, < 0.012-0.10 microgram/ml, and < 0.025-0.78 microgram/ml, respectively. These antibiotics could be recommended for treatment of patients in early stage of Lyme disease in Japan.

Amoxicillin↗
PubMed1994

Polymerase chain reaction analysis of Borrelia species isolated in Japan.

Primer reactivities of 25 Borrelia burgdorferi sensu lato isolates from the ticks, Ixodes persulcatus and I. ovatus, in Japan and 10 isolates in Europe and North America were investigated. The methods used in this study were the polymerase chain reaction (PCR) on the flagellin structural gene (fla), the outer surface protein A gene (osp A) and the outer surface protein B gene (osp B), and the restriction fragment length polymorphism (RFLP) analysis of PCR products from osp A and osp B. The flagellin PCR primer set reacted with all the Borrelia strains tested. Four genospecies, B. burgdorferi sensu stricto, B. garinii, B. afzelii and B. japonica, were differentiated by PCR using osp A and osp B primers combined with RFLP analysis. Some Japanese isolates from I. persulcatus were identified as B. garinii or B. afzelii. The other isolates from I. persulcatus did not fit in any of the 4 genospecies. These results suggested that Japanese isolates from I. persulcatus are highly heterogeneous in their osp A and osp B structures. Furthermore, PCR primers targeting fla are applicable to the gene diagnosis for Lyme disease in Japan, and osp A and osp B primers can be used to classify B. burgdorferi sensu lato isolates into genospecies by PCR and RFLP analyses.

Bacterial Outer Membrane Proteins↗
PubMed1994

Infectivity and early antibody response to Borrelia burgdorferi sensu lato isolated in Japan in outbred mice.

Borrelia burgdorferi sensu lato isolated from Ixodes ovatus (B. japonica), I. persulcatus and patients with erythema migrans (EM) in Japan were determined on infectivity and arthritis induction-activity in outbred mice. Infectivity of B. japonica was weak and did not induce the development of footpad swelling by subcutaneous (s.c.) inoculation into the footpad. Challenged strain, NO129-M of B. japonica, to ddY mice were reinoculated to the mice at various cell numbers (1 x 10-1 x 10(6) cells/mouse). The strain isolated from the mouse did not reinfect ddY mice and did not induce the production of specific antibody to the homologous strain. On the other hand, strains from I. persulcatus and patients with EM in Japan infected the mice and induced a serious inflammatory response in Borrelia-inoculated footpad as well as strains belonging to the three genospecies, B. burgdorferi sensu stricto, B. garinii, and B. afzelii, related to Lyme disease, from North America and Europe. The mice were infected with 10 cells of strain HP1 isolated from I. persulcatus in Hokkaido and of strain 297 isolated from a patient in the U.S.A. by subcutaneous inoculation into the hind footpad, or by intradermal inoculation into the back. Antigens of ca. 20, 23-24 (Osp C), 29, 39, 41 (flagellin) and 45 kDa reacted with the pooled sera from mice inoculated with strains HP1 and 297, but Osp A and Osp B did not.

Animals↗
PubMed1994

A histochemical study of the biceps brachii muscle cross-innervated by intercostal nerves. 6 cases of brachial plexus injuries operated with nerve-crossing.

Direct nerve-crossing of intercostal nerves from the lateral thorax to the musculocutaneous nerve was performed in 6 patients after spinal nerve root avulsion with brachial plexus palsy. Elbow flexion power was regained well enough to move against gravity and some resistance in all cases. The muscles were examined histochemically 4 (1-9) years after the operation. The intercostally-innervated biceps brachii muscle showed motor predominance of slow-twitch Type 1 fiber regeneration much more than that of fast-twitch Type 2 fiber in 5 of our patients. Our study suggests that the motor nerves of slow-twitch fibers may have priority in peripheral nerve regeneration over those of fast-twitch fibers.

Adolescent↗
PubMed1994

Lyme disease spirochetes in a wild fox (Vulpes vulpes schrencki) and in ticks.

Lyme disease spirochetes were demonstrated in a wild female fox (Vulpes vulpes schrencki) and in Ixodes persulcatus ticks collected from the fox on Sapporo, Hokkaido, Japan. Spirochetes were detected in I. persulcatus, as well as skin lesions, brain, heart, kidney, and liver of the fox. Five of seven isolates reacted with a monoclonal antibody against Borrelia afzelii specific Osp B. Deoxyribonucleic acid (DNA) relatedness of a brain isolate was 89% to B. afzelii, and ranged from 50 to 67% to three other species. Immunoglobulin G antibodies to B. afzelii, B. garinii and B. burgdorferi sensulato, when tested in an enzyme-linked immunosorbent assay (ELISA), were negative in the fox. There were no antibodies against seven serovars of Leptospira interrogans.

Animals↗
PubMed1994

Magnetic stimulation of biceps after intercostal cross-innervation for brachial plexus palsy. A study of motor evoked potentials in 25 patients.

We studied the motor evoked potentials (MEP) in the biceps of 25 patients with traumatic brachial plexus palsy from root avulsion after cross-innervation by intercostal nerves. We used transcranial, transcervical and transthoracic magnetic stimulation at 8 to 235 months (mean 51) after transfer of intercostal nerves to the musculocutaneous nerve. Biceps strength recovered to MRC grade 2 in eight patients, grade 3 in three and grade 4 in 14. The mean latency of the MEP in the normal biceps on transcranial stimulation was 12.5 +/- 1.3 ms and on transcervical stimulation 6.3 +/- 1.1 ms. After intercostal reinnervation the mean latency on transcranial stimulation was 21.7 +/- 4.5 ms and on transthoracic stimulation 11.6 +/- 3.8 ms. The latency of the biceps MEP after reinnervation by intercostal nerves on transcranial and transthoracic magnetic stimulation correlated well with the duration of follow-up and the latency of the MEP on transthoracic magnetic stimulation correlated significantly with muscle power.

Adolescent↗
PubMed1994

A new method for quantitative estimation of the degree of DNA fragmentation utilizing agarose gel electrophoresis.

We designed a new method for quantitative analysis of the degree of DNA fragmentation, a characteristic feature of apoptosis. A photograph of an agarose gel electrophoresis of fragmented DNA was incorporated by an optical density scanner or equivalent equipment, and the integrations of middle molecular size area (10,000 to 300 bp), single nucleosomal size area (smaller than 300 bp) and total lane area were calculated. We defined fragmentation rate or (%)FR as the amount of fragmented DNA expressed as the percentage of the total amount of DNA, assigning the coefficients of 1 and 0.5, respectively, to the fragments completely digested into single nucleosomal length and to those partially digested (between 10 k to 300 bp). A standard calibration curve was constructed from triplicate experiments of target nuclei digestion by micrococcal nuclease, which revealed that this method covered a wide range of nuclease activity. We also confirmed that our method was applicable to an autodigestion assay of isolated nuclei which represented endogenous endonuclease activities. This method may be a useful tool for quantitative analysis of endonuclease activities capable of producing nucleosomal-size DNA fragmentation.

Apoptosis↗
PubMed1994

Marked apoptosis of human myelomonocytic leukemia cell line P39: significance of cellular differentiation.

Myelodysplastic syndrome (MDS)-derived leukemia cell line P39/Tsugane could be induced to apoptosis by a variety of agents including metabolic inhibitors, a calcium ionophore and differentiation-inducing agents. As evaluated by characteristic morphological changes and oligonucleosomal lengths DNA ladder, the levels of apoptosis in P39 cells induced by actinomycin D, or A23187, were far greater than in other myeloid lines examined in this study. When 22-oxa-1 alpha, 25(OH)2D3 (D3), dimethyl sulfoxide (DMSO) and all-trans retinoic acid (RA) were used as differentiation-inducers, varying degrees of apoptosis were seen. D3 induced monocytoid differentiation, but not apoptosis above the control level. On the other hand, RA induced profound apoptosis concomitant with the progressive expression of differentiation markers. Studies on morphology, functions and phenotypes of P39 cells exposed to differentiation inducers suggest that the incidence of apoptosis was not affected by the process of differentiation, but cells in the process of varying degrees of differentiation may die via apoptosis. Moreover, RA-treated P39 cells are unique in the simultaneous occurrence of profound apoptosis and differentiation. We propose that RA-treated P39 differentiation model is ideally suited for the study of MDS.

Apoptosis↗
PubMed1993

Detection of Mg(2+)-dependent endonuclease activity in myeloid leukemia cell nuclei capable of producing internucleosomal DNA cleavage.

We detected Mg(2+)-dependent, Ca(2+)-independent endonuclease activity in non-apoptotic myeloid leukemia cell nuclei using autodigestion method which cleaved the chromatin of the autologous leukemia cells to an oligonucleosomal length pattern. Similar endonuclease activity could be successfully recovered in the protein extracts of the human leukemia cell nuclei. The extracts consistently elicited characteristic DNA cleavage of another leukemia cell (KG-1) nuclei as the target, the enzyme activity of which had been inactivated. We propose that this method is a useful tool for the study of endonucleases involved in apoptosis.

Animals↗
PubMed1993

Serial changes in endogenous erythropoietin levels in patients with myelodysplastic syndromes and aplastic anemia undergoing erythropoietin treatment.

Recombinant human erythropoietin (rhEpo) was administered to 14 patients with myelodysplastic syndrome (MDS) and seven patients with aplastic anemia (AA). In 19 patients, doses of 6000 units were given intravenously three times a week (t.i.w.) with the dose being doubled up to 24,000 units every 8 weeks until a response was obtained. RhEpo was given subcutaneously in two patients. Seven patients, four with MDS and three with AA, showed a significant response with an increase of hemoglobin concentration during therapy. The response occurred at doses of 12,000 units in five and 24,000 units in two patients. Responding patients with both MDS and AA had a relatively low serum Epo (s-Epo) level prior to Epo therapy. MDS responders had either refractory anemia (RA) or RA with ring sideroblasts (RARS), while two of the Epo responders in AA had a severe form of the disease. However, since some of the Epo responders had a high initial s-Epo concentration, a high s-Epo level does not preclude the use of rhEpo. Serial determination of s-Epo levels showed a progressive decline in six of the seven responders even when they were on rhEpo therapy, while the s-Epo levels remained elevated or further increased with time in most nonresponders. RhEpo was well tolerated by all patients. The results suggest that rhEpo is a safe and effective treatment for a certain proportion of patients with MDS and AA. Moreover, serial determination of s-Epo during therapy may be useful in monitoring and predicting the therapeutic effect of rhEpo.

Adolescent↗
PubMed1993

Development of a specific enzyme-linked immunosorbent assay for the hepatitis C virus antibody using clone 14.

The authors isolated a specific cDNA clone (clone 14) for non-A, non-B hepatitis virus infection. In this study, we developed an enzyme-linked immunosorbent assay (ELISA) using a synthetic oligopeptide encoded by clone 14 and examined its usefulness for detecting hepatitis C virus (HCV) antibody in 181 patients with chronic NANB hepatitis, 88 with cirrhosis and 24 with hepatocellular carcinoma associated with NANB hepatitis virus. Anti-clone 14 antibody was detected in 75% of patients with chronic NANB hepatitis, 57% of cirrhotic patients and 58% hepatocellular carcinoma patients. Anticlone 14 and anti-C-100 antibody assayed using a commercial kit were found in serum from 199 (69%) and 205 (70%) of these 294 patients, respectively. Approximately 85% of the patients showed the presence of anticlone 14 and/or anti-C-100 antibodies. We compared the presence of these antibodies and the second generation anti-HCV antibody using ELISA and HCV RNA by the polymerase chain reaction assay, in the same blood samples from 49 patients with chronic liver disease who had anti-clone 14 and/or anti-C-100 antibody. HCV RNA was detected in 38 of 40 (95%) plasma samples containing anti-clone 14 antibody, the prevalence of which was similar to that for anti-C-100 antibody (41/42, 98%) and the second generation anti-HCV antibody (46/47, 98%). Furthermore, 6 of 7 plasma samples containing anti-clone 14 antibody and lacking anti-C-100 antibody were positive for the second generation anti-HCV antibody and HCV RNA.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1993

Treatment of residual instability and extensor lag in polydactyly of the thumb.

Extensor indicis tendon transfers were used in six cases with residual deformity of the thumb in polydactyly. The indication was extensor lag and instability of the interphalangeal joint. At mean follow-up of three and a half years, normal stability was improved. Full extension was achieved in three cases and two cases also derived some benefits from this operation. Alignment was improved in five cases.

Child↗
PubMed1993

Genomic analysis of Borrelia japonica sp. nov. isolated from Ixodes ovatus in Japan.

Genetic characteristics of 12 Borrelia isolates from the tick, Ixodes ovatus, I. persulcatus, and the rodent, Apodemus speciosus ainu, in Japan were compared to members of the three genospecies of Borrelia burgdorferi sensu lato; B. burgdorferi sensu stricto, B. garinii and group VS461. The methods used in this study were the quantitative microplate DNA hybridization assay and restriction fragment length polymorphism (RFLP) analyses of the flagellin structural genes and the 16S rRNA genes. The six isolates from I. persulcatus and A. speciosus ainu were identified as genospecies B. garinii using RFLP analysis of the flagellin and 16S rRNA genes. In contrast, RFLP analysis of the six isolates from I. ovatus indicated that they were different from the three reported genospecies. DNA homology studies confirmed the RFLP results. The six isolates from I. ovatus had DNA homologies ranging from 85 to 99%, whereas DNA relatedness of the I. ovatus isolate with strains belonging to the three genospecies was 50 to 64%. These results suggest that the strains isolated from I. ovatus in Japan differ from the three genospecies and should be classified as a new genospecies of B. burgdorferi sensu lato. We propose that strains isolated from I. ovatus should be classified as B. japonica sp. nov.

Animals↗
PubMed1993

Evoked spinal cord potentials for diagnosis during brachial plexus surgery.

We used evoked spinal cord potentials (ESCP) for intraoperative diagnosis in 17 cases of traumatic brachial plexus palsy. Forty spinal nerves were directly stimulated during exploration of the brachial plexus and ESCP recorded from the cervical epidural space were compared with simultaneously observed somatosensory evoked potentials (SEP) and myelographic findings. Both SEP and ESCP could be evoked in 21 spinal nerves but ESCP were always more distinct and five to ten times greater in amplitude than SEP. In four nerves, ESCP but no SEP were produced, suggesting that there was continuity from the nerves to the spinal cord. ESCP were obtained from two spinal nerves which appeared to be abnormal on the myelogram. The results show that intraoperative electrodiagnosis by epidural ESCP recordings can provide useful information on the lesions of traumatic brachial plexus palsy.

Adolescent↗
PubMed1993

Time-course detection of HIV-1 proviral DNA and genomic RNA by polymerase chain reaction in sera from seropositive and seronegative hemophiliacs treated with clotting factor concentrates.

The detection of HIV-1 proviral DNA and genomic RNA was performed by polymerase chain reaction (PCR) in hemophiliacs treated with non-heated clotting factor concentrates. Reamplification with double PCR was performed on those samples that were negative for single PCR. Primer pairs of the gag, env, and pol regions were used for the amplification of HIV-1 proviral DNA sequences. Amplification of the gag region by the SK38/SK39 primer pair was useful for the detection of proviral DNA sequences. With double PCR, 44 of 47 seropositive samples (93.6%) were PCR-positive. All 23 seronegative samples were PCR-negative. Reverse transcription and PCR amplification (RT-PCR) according to the primer pair of the gag region were performed to detect HIV-1 genomic RNA sequences. Double RT-PCR analysis of the HIV-1 RNA sequence in frozen-preserved sera revealed that 49 of 55 seropositive sera (89.1%) were PCR-positive. Although quantification of the PCR method was not performed in this study, we concluded that, in patients in whom proviral DNA or genomic RNA sequences are detected with difficulty with PCR, the onset and progression of HIV-1 infection is delayed.

Blood Coagulation Factors↗
PubMed1993

[Studies on fatigue and stress of anesthesiologist during anesthetic works using Holter ECG].

We evaluated fatigue, stress and workload of anesthesiologists during anesthetic works using Holter ECG. Recorded heart rates of anesthesiologists enable us to draw the task graph and to calculate the workload scores according to their task behavior. We conclude that the application of Holter ECG is useful in measuring the fatigue, stress, and especially workload of anesthesiologists.

Anesthesiology↗
PubMed1993

[Detection of HIV-1 proviral DNA and RNA in serum from HIV-1 sero-positive hemophiliacs by polymerase chain reaction].

We amplified HIV-1 proviral DNA and RNA in serum by DNA-PCR and RT-RCR in 20 HIV-1 seropositive hemophiliacs asymptomatic carrier (AC): 10, AIDS-related complex (ARC):8, AIDS:2). HIV-1 DNA sequences were identified in 44 (93.6%) of 47 specimens. 23 (92.0%) of 25 samples in AC, 13 (100%) of 13 in ARC, 8 (88.8%) of 9 in AIDS had detectable bands. RNA sequences were identified in 36 (85.7%) of 42 specimens. 17 (70.8%) of 24 specimens in AC, 13 (100%) of 13 in ARC, 5 (100%) of 5 in AIDS cases had detectable bands. RNA in serum was strongly positive in two asymptomatic patients with progression to AIDS who showed no changes of other markers. Patients with almost normal CD4 cell counts had trace amounts of proviral DNA and RNA in serum. RNA in serum is the parameter most predictive of progression to AIDS and is detectable earlier than other parameters. From the results of RT-PCR before and after seroconversion, the serum of one patient was shown to be positive at 5 months before seroconversion.

Acquired Immunodeficiency Syndrome↗