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Biomedical subjects

H Machida

Publications and source records attributed to H Machida.

At least 73 records · Page 4Linked to original sources
PubMed1991

[Roentgenological manifestation of ossification of the posterior longitudinal ligament in the cervical spine causing severe spinal canal stenosis--a group comparison with and without marked spinal cord dysfunction].

Relationship between the degree of clinical symptoms and the lateral roentgenograms of the cervical OPLL causing severe spinal canal stenosis was studied among patients whose roentgenological minimum antero-posterior diameters of the available spinal canals were under 9mm. Lateral roentgenograms of 28 clinically mild patients were compared with those of 20 clinically severe patients. The type of ossification, the extent of OPLL, the narrowest level of the available spinal canal, and the minimum a-p diameter were not statistically significant parameters. The degree of canal stenosis at the 1cm cranial and 1cm caudal levels from the narrowest level, and the axial extent of canal stenosis around the narrowest level were less significantly in the group with mild symptoms than in the group with severe symptoms.

Adult↗
PubMed1990

Importance of retinal pigmentation as a subclinical marker in familial adenomatous polyposis.

Surgery was performed in 35 patients with familial adenomatous polyposis (FAP) from 22 family trees. To clarify retinal pigmentation as an important subclinical marker in patients with FAP, precise retinal examinations were performed in 41 cases (82 eyes), including 23 patients and 18 family members including 12 second-generation and third-generation possible carriers. In 27 patients, precise studies were done on accompanying lesions, and the number of polyps was counted at the time of surgery in each patient in every family tree. The overall incidence of retinal pigmentation in patients was 82.6 percent. The incidence of retinal pigmentation in possible carriers was found to be 50 percent, which is comparable with the calculated expressibility of the polyps. The shape and distribution of pigmentations were classified into two categories--large and small. A total of 1984 control retinal examinations were performed, which revealed only six retinal pigmentations (0.3 percent). In the control group, all pigmentation was solitary and unilateral. No large pigmentations in bilateral eyes were found in the control group. In large pigmentation, the sensitivity and specificity were calculated as 0.652 and 0.999, respectively, and in small pigmentation, the sensitivity and specificity were calculated as 0.783 and 0.997, respectively. Small pigmentation appears to increase in number around the age of the appearance of the polyp. Earliest recognition of the pigmentation in this series was one year of age.

Adenomatous Polyposis Coli↗
PubMed1990

Comparison of antiviral efficacies of 1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl)uracil (brovavir) and acyclovir against herpes simplex virus type 1 infections in mice.

1-beta-D-Arabinofuranosyl-E-5-(2-bromovinyl)uracil (brovavir) and acyclovir were compared for their antiviral effects against herpes simplex virus type 1 (HSV-1) model infections in mice. Both drugs were not toxic to mice when they were administered orally by the same schedule used for therapeutic experiments. Brovavir was less toxic than acyclovir when injected by the intraperitoneal (i.p.) route. Marked efficacies of brovavir by either oral or i.p. administration were demonstrated in both experimental encephalitis and i.p. infection with HSV-1 WT-51 strain. Treatment with brovavir at a dose of 15 or 25 mg/kg twice daily resulted in increasing both survival rate and mean survival time of the infected mice. On the contrary, acyclovir showed only marginal effect against the experimental encephalitis. Survival rates of mice treated with brovavir were higher than those treated with acyclovir at corresponding doses with statistical significance. The superiority of brovavir was also found in the intracerebral infection with strain VR-3, a highly virulent strain for mice. Brovavir, but not acyclovir, at a dose of 200 mg/kg reduced the mortality. Acyclovir, however, were significantly effective in reducing mortality of systemically infected mice by both oral and i.p. administrations. The effective dose of acyclovir was lower than that of brovavir against i.p. infection with strain WT-51. Differences in mortality of strain VR-3-infected mice were statistically significant between acyclovir- and brovavir-treated groups.

Acyclovir↗
PubMed1990

Drug susceptibilities of isolates of varicella-zoster virus in a clinical study of oral brovavir.

Susceptibilities to brovavir [1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl)-uracil] and acyclovir of clinical isolates of varicella-zoster virus obtained from 58 patients with herpes zoster, included in a clinical trial of oral brovavir, were tested by a plaque reduction method. All 101 isolates were significantly susceptible to brovavir; 50% effective dose of brovavir for these isolates ranged between 0.6-4.0 ng/ml (average: 1.29 ng/ml). Brovavir was about 3,000 times more potent than acyclovir against these isolates. No marked change in the susceptibility of isolates from these patients during treatment with brovavir was observed.

Acyclovir↗
PubMed1990

Antiviral potencies of BV-araU and related nucleoside analogues against varicella-zoster virus in different cell lines.

1-beta-D-Arabinofuranosyl-E-5-(2-bromovinyl)uracil (BV-araU) and nine other antiherpesviral nucleoside analogues were compared for their potencies against four strains of varicella-zoster virus (VZV) on three different cell lines: HEL cells, Vero cells, and MS cells established from a human malignant schwannoma. In contrast to the activity against herpes simplex virus type 1 previously reported, BV-araU showed extremely marked antiviral activity against VZV even on Vero cells. ED50, 50% plaque reduction dose, of BV-araU for VZV was 0.20-3.1 and 0.14-0.63 ng/ml on Vero cells and on HEL cells, respectively. Potency of BV-araU on MS cells was similar to that on these cell lines. There was not significant variation in anti-VZV activities of other nucleoside analogues on these three different cell lines except a few combinations of VZV strain and test compound.

Animals↗
PubMed1990

Effect of 1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl)uracil against herpes simplex virus type 1 infection in immunosuppressed mice.

1-beta-D-Arabinofuranosyl-E-5-(2-bromovinyl)uracil (BV-araU) reduced the mortality rates of (i) 7-week-old, cyclophosphamide-treated, immunosuppressed mice (CYP mice) intraperitoneally infected with a moderately virulent strain of herpes simplex virus type 1 and (ii) 4-week-old CYP mice infected with a less virulent strain at doses of 20 and 50 mg/kg of body weight twice daily and 5 mg/kg, respectively. The degree of efficacy of BV-araU was equivalent to that of acyclovir in 4-week-old CYP mice infected with the less virulent strain. BV-araU (20 mg/kg) suppressed viral growth in various organs of CYP mice.

Acyclovir↗
PubMed1990

Effect of 1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl)uracil (brovavir) on experimental infections in mice with herpes simplex virus type 1 strains of different degrees of virulence.

In vivo antiherpesvirus effects of 1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl)uracil (brovavir) were tested in two mouse model infections with herpes simplex virus type 1 (HSV-1) strains which showed different degrees of virulence in mice. Successful efficacies of oral and intraperitoneal (i.p.) treatments with brovavir were demonstrated in both intracerebral and i.p. infections with the HSV-1 WT-51 strain of moderate virulence. However, only weak or modest effects of brovavir were observed against the two model infections with a highly virulent strain, HSV-1 VR-3. Brovavir was not effective in reducing mortality of mice infected i.p. with HSV-1 KOS, which exhibited the highest virulence in mice among HSV-1 strains used when inoculated i.p. However, the drug had a significant effect on intracerebral infection with the KOS strain. Efficacies of oral treatment with brovavir were almost equal to those of i.p. administration in the model infections. After intracerebral inoculation, the VR-3 strain grew in brains of mice at a higher rate than the WT-51 strain. By oral treatment with 50 mg of brovavir per kg twice daily, replication of the WT-51 strain in the brains was markedly suppressed and was eliminated after transient elevation of the titer. Growth of the VR-3 strain in the brains was simply delayed by the drug treatment. Thus, the antiviral efficacy of brovavir in mice was affected by the degree of virulence of the challenge virus strain used for infection.

Animals↗
PubMed1990

[A case of adrenal myelolipoma].

Adrenal myelolipoma is a rare, nonfunctioning, and benign tumor composed of varying proportion of fat and bone marrow elements. A case is presented of a thirty-six-year-old woman in whom the diagnosis of adrenal myelolipoma was suspected preoperatively by ultrasonography, computed tomography, and magnetic resonance imaging (MRI). The patient cured by surgery. Histological examination showed mature adipose tissue and normal hemopoietic tissue. This is the first report which describes MRI of adrenal myelolipoma in Japan.

Adrenal Gland Neoplasms↗
PubMed1990

Investigation and outcome of 121 infants and children requiring Nissen fundoplication for the management of gastroesophageal reflux.

In a 6.5 year period starting January 1982, 121 patients (74 male, 47 female; 1.6:1) with complicated gastroesophageal reflux referred to Alberta Children's Hospital, University of Calgary, required a Nissen fundoplication at a mean age of 35.5 months (range 3 weeks to 18 years). The median age of onset of symptoms was less than 1 month. Symptoms and indications for surgery included regurgitation (88%), failure to thrive (52%), reflux-associated pulmonary symptoms and aspiration (48%), biopsy evidence of esophagitis (35%) with heartburn (17%), dysphagia (18%), hematemesis (17%), anemia (13%), and hypoproteinemia (22%). Sixty-four percent of the patients had a syndrome or chromosomal abnormality, respiratory disease, or neuromuscular disorder. The barium contrast upper-gastrointestinal radiographic series, performed in all patients, identified structural [gastric outlet obstruction (2%), esophageal stricture (11%), erosive esophagitis (9%)], and functional abnormalities [gastroesophageal reflux (90%), barium aspiration (8%), esophageal hypoperistalsis (30%), delayed gastric emptying (4%)]. Barium contrast upper gastrointestinal radiographic series identified gastroesophageal reflux with a sensitivity of 90% (compared to history), was 50% sensitive and 92% specific for erosive esophagitis (compared to biopsy), was 59% sensitive and 74% specific for esophageal dysmotility (compared to esophageal manometry), and there was a significant (p less than 0.01) association between barium aspiration and prior evidence of aspiration pneumonitis. Esophageal manometry demonstrated a significantly (p less than 0.001) lower esophageal sphincter pressure in patients compared with controls, but no significant correlation with failure to thrive, aspiration pneumonia, biopsy evidence of esophagitis, or parameters of the 24-hour esophageal pH study. Twenty-four hour pH monitoring showed significantly (p less than 0.05) more reflux episodes than in asymptomatic controls and there was significant (p less than 0.05) correlation between the percentage of time pH was less than 4 and the presence of hypoalbuminemia, and biopsy-proven erosive esophagitis or Barrett's esophagus. Endoscopic appearance was 91% sensitive and 60% specific for esophagitis when compared to biopsy. Nissen fundoplication was completely effective at resolving gastroesophageal reflux in 83%, and associated with marked improvement in 15%. No patient died as a result of fundoplication. Major complications included: recurrence of symptoms requiring reoperation (2%), subsequent mechanical bowel obstruction (8%), wound infection or pneumonia (12%).

Adolescent↗
PubMed1990

[Transcatheter arterial embolization for massive abdominal bleeding in post-pancreatoduodenectomy--first report].

Transcatheter arteria embolization (TAE) was carried out for 10 cases (14 times) with massive intra-abdominal bleeding after pancreatoduodenectomy (PD). The results obtained were as follows: 1. The ten patients (carcinoma of the pancreas head 4, carcinoma of the papilla Vater: 3, carcinoma of the bile duct: 2. leiomyosarcoma of the duodenum: 1) included eight men and two women aged 45 to 75, with an average age of 63.7. The time span before TAE was instituted averaged 20.8 days. 2. Infection due to leakage noted in all cases. 3. A good course was noted when manifestation of symptoms related to poor sutures or the onset of intra-abdominal bleeding after PD was delayed and the time from the onset of intra-abdominal bleeding to TAE was short. 4. Bleeding sites could be determined in all cases. Pseudoaneurysm accounted for five and extravasation accounted for nine of the total of 14 bleeding sites. The prognosis was apparently good in cases of pseudoaneurysm as compared with that in cases of extravasation. 5. Bleeding was controlled in all cases. 6. No complication due to TAE occurred. These results indicate the TAE is a safe and effective procedure for the control of massive intra-abdominal bleeding after PD.

Abdomen↗
PubMed1989

Mechanism of selective inhibition of varicella zoster virus replication by 1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl)uracil.

To investigate the mechanism of action of 1-beta-D-arabinofuranosyl-(E)-5-(2-bromovinyl)uracil (BV-araU) on varicella zoster virus (VZV) replication, we examined the metabolism of the drug in VZV-infected cells using 14C-labeled BV-araU. [14C]BV-araU was taken up by the cells infected with thymidine kinase-positive (TK+)VZV, but not so much by TK- VZV-infected or mock infected cells. Most of the radioactivity in TK+ VZV-infected cells that were incubated with [14C]BV-araU was recovered from their acid-soluble fraction, and little from their acid-insoluble fraction. By high performance liquid chromatographic assay of the acid-soluble fraction, it was proved that BV-araU was metabolized to its 5'-monophosphate, diphosphate, and triphosphate only in TK+ VZV-infected cells. The radioactivity was not detected in VZV nucleocapsids or in VZV DNA and cellular DNA isolated from TK+ VZV-infected cells, even if BV-araU was added at a 1000 times higher concentration than the 50% inhibitory dose for VZV replication in vitro. Furthermore, it was enzymatically proved that [14C]BV-araU was selectively and effectively phosphorylated to BV-araU monophosphate by VZV TK and that affinity of BV-araU triphosphate for VZV DNA polymerase was the quite strong. From these results, it can be concluded that marked inhibition of VZV replication by BV-araU is due to selective phosphorylation of BV-araU in the TK+ VZV-infected cells and strong inhibition of VZV DNA synthesis by BV-araU triphosphate, without detectable incorporation into VZV DNA.

Antiviral Agents↗
PubMed1989

[The rabbit thermo-regulatory system. Effects of high dose of sodium fluoride].

The mechanism of sodium fluoride (NaF) induced hypothermia was investigated on relations between the monoamine synthesis and metabolism in the rabbit brain. Five male rabbits per a group, weighing about 2.5kg and having rectal temperatures of 38.4 to 39.3 degrees C, were used in this experiment. The rectal temperature measurements were made by means of an electric thermometer for 5 hours at intervals of 15 or 30 minutes. Through this experiment, animals were housed in a room kept at 22 to 23 degrees C. The following drugs were used in this experiment: NaF (40 mg/kg i.v.), barbital sodium (0.1 g/kg s.c.), hexamethonium bromide (C6, 10 mg/kg i.v.), ergotamine tartrate (30 mg/kg s.c.), phenoxybenzamine hydrochloride (15 mg/kg i.v.), propranolol hydrochloride (5 mg/kg s.c.), pindolol (0.3 mg/kg s.c.), atropine sulfate (30 mg/kg s.c.), 2, 4-dinitrophenol (DNP, 20 mg/kg i.v.), l-DOPA (20 mg/kg i.v.), 5-HTP (20 mg/kg i.v.) Results 1. Intravenous injection of 30 mg/kg of NaF induced a drop of 0.66 degrees C in rectal temperature. 2. Pretreatment with 0.1 mg/kg of barbital sodium or 10 mg/kg of C6 prominently inhibited the NaF-induced hypothermia. 3. The alpha-blockade caused by ergotamine tartrate and phenoxybenzamine or the beta blockade by propranolol hydrochloride and pindolol resulted in an approximate 50% inhibition of maximum drop in body temperature induced by NaF administration. Both alpha- and beta-blockades caused by ergotamine tartrate and propranolol or by phenoxybenzamine and pindolol, however, made a remarkable inhibition of the NaF effect. Cholinergic blockade brought on by atropine sulfate, on the other hand, had no effect against NaF-induced hypothermia. 4. Bilateral splanchnicotomy completely inhibited drops in rectal temperature. 5. Intravenous injection of NaF 40 mg/kg failed to counteract the rise of rectal temperature caused by DNP 20 mg/kg. 6. Pretreatment with l-DOPA made a prominent inhibition of NaF-induced hypothermia. The inhibiting effects of 5-HTP, however, were slight. 7. Administration of NaF made a significant decrease in norepinephrine levels in the rabbit hypothalamus, but had no effect on 5-HT levels.

Animals↗
PubMed1988

Effect of stilbenedisulfonate binding on the state of association of the membrane-spanning domain of band 3 from bovine erythrocyte membrane.

The membrane-spanning domain of bovine band 3, the anion transport protein of erythrocyte membrane, was purified in the presence of nonaethyleneglycol lauryl ether (C12E9) and the effect of a covalent attachment of 4,4'-diisothiocyanostilbene-2,2'-disulfonate (DIDS), a potent transport inhibitor, on the state of association of the domain isolated (the 58 kDa fragment) was studied via gel filtration, gel electrophoresis and sedimentation velocity experiments. It was indicated that the DIDS-unlabeled fragment in C12E9 solution forms heterogeneous aggregates which are larger in size than the dimer. This contrasted with the behavior that bovine band 3 is present as dimers or tetramers in the same medium (Nakashima and Makino (1980) J. Biochem. 88, 933-947). When DIDS was covalently attached, the fragment was present as a single molecular species which was indicated to be a dimer by molecular weight determination. The secondary structure of the fragment was not affected by DIDS. The change in the state of association caused by the DIDS-binding was also found in the presence of sucrose monolaurate (SE12), which was a more potent detergent for extraction of the 58 kDa fragment from membranes than C12E9. However, the complex with SE12 was extremely unstable.

4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid↗
PubMed1988

Effects of various nucleosides on antiviral activity and metabolism of 1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl)uracil against herpes simplex virus types 1 and 2.

Uptake of 1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl)uracil (BV-araU) into herpes simplex virus type 1 (HSV-1)- and 2 (HSV-2)-infected cells was elevated about 190 to 40 times, compared with that into mock-infected human embryo lung fibroblast cells. Uptake was not enhanced by infection with thymidine kinase-negative HSV-1 and HSV-2 mutants, however. In HSV-1-infected cells, 9.7% of BV-araU was phosphorylated to BV-araU triphosphate, but only 1.1% was phosphorylated in HSV-2-infected cells. The antiviral effect, uptake, and turnover of BV-araU were inhibited significantly by thymidine (dThd), moderately by deoxyuridine, and not at all by deoxycytidine. On the other hand, the antiviral activity of acyclovir (ACV) was inhibited only by dThd. The effect of BV-araU was influenced by dThd and dThd phosphates (mono-, di-, and triphosphates), and the effect of ACV was influenced only by dThd, which competitively inhibited the phosphorylation of ACV to ACV monophosphate. The combination of 5-fluorodeoxyuridine (FUdR)-BV-araU or FUdR-ACV had a synergistic effect on HSV-1 and HSV-2 replication. The effect of FUdR on the turnover of BV-araU in HSV-1- and HSV-2-infected cells was analyzed by high-performance liquid chromatography. In HSV-1-infected cells, 86% of the BV-araU was phosphorylated to BV-araU triphosphate, but no effect was observed in HSV-2-infected cells, in which 98% of the BV-araU remained as BV-araU monophosphate.

Antiviral Agents↗
PubMed1988

Efficacies of antiherpesvirus nucleosides against two strains of herpes simplex virus type 1 in Vero and human embryo lung fibroblast cells.

Antiviral activities of five nucleoside analogs against the VR-3 and WT-34 strains of herpes simplex virus type 1 (HSV-1) were investigated in Vero and human embryo lung fibroblast (HEL) cells. In HEL cells, the compounds showed antiviral activities against both strains of HSV-1, but in Vero cells, the antiviral activities of the compounds were reduced in proportion to their antiviral indexes (the 50% inhibitory dose [ID50] for cell growth divided by the 50% plaque reduction dose for virus). The ratio of the ID50 in Vero cells to the ID50 in HEL cells was larger in VR-3-infected cells than in WT-34-infected cells. The following results were obtained. (i) Thymidine kinase (TK; EC 2.7.1.21) activity in the VR-3- or WT-34-infected Vero cells was about half that in VR-3- or WT-34-infected HEL cells. Induction of viral TK was especially low in the VR-3-infected Vero cells. (ii) The ID50 of the plaque reduction assay in hypoxanthine, aminopterin, and thymidine medium revealed that the activity of cellular thymidylate synthetase (EC 2.1.1.45) was important in viral replication in VR-3-infected Vero cells. (iii) The VR-3-infected cells required larger thymidine and thymidine phosphate pools for viral replication than the WT-34-infected cells did, although uptake of 1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl) uracil into infected cells was equal for both strains. (iv) In the VR-3-infected Vero cells, the quantity of 1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl)uracil triphosphate was smaller than that in VR-3-infected HEL cells and WT-34-infected Vero and HEL cells.

Acyclovir↗
PubMed1988

Comparison of two bromovinyl nucleoside analogs, 1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl)uracil and E-5-(2-bromovinyl)-2'-deoxyuridine, with acyclovir in inhibition of Epstein-Barr virus replication.

The effect of 1-beta-D-arabinofuranosyl-E-5-(2-bromovinyl)uracil (BV-araU), a new antiviral drug, on Epstein-Barr virus (EBV) was studied and compared with those of E-5-(2-bromovinyl)-2'-deoxyuridine (BVdU) and acyclovir (ACV). BV-araU effectively inhibited EBV replication both in superinfected Raji cells and in virus producer P3HR-1(LS) cells, as determined by density gradient centrifugation, in situ cytohybridization with an EBV DNA probe, and cRNA-DNA hybridization. The 50% effective doses for viral DNA replication were 0.26, 0.06, and 0.3 microM for BV-araU, BVdU, and ACV, respectively. The relative efficacy on the basis of the in vitro therapeutic index was BVdU (6,500) greater than BV-araU (1,500) greater than ACV (850). Synthesis of EBV-induced polypeptides with molecular weights of 145,000 and 140,000 was inhibited by these drugs. Kinetic analysis of reversibility of inhibition of EBV DNA replication after removal of the drugs indicated that BV-araU, like BVdU, has a more prolonged inhibitory effect than ACV. These results indicate that the 2' OH group in the arabinosyl configuration of BV-araU results in marked reduction in anti-EBV activity while slightly diminishing cytotoxicity.

Acyclovir↗