Biomedical subjects

K Hamada

Publications and source records attributed to K Hamada.

At least 199 records · Page 11Linked to original sources

PubMed1997

Anti-nuclear antibodies and the optic-spinal form of multiple sclerosis.

We found anti-nuclear antibodies (ANA) (1:20 or higher) in sera from 11 of 16 patients with a diagnosis of the optic-spinal form of multiple sclerosis (OpS-MS) and 13 of 59 patients with other forms of MS (other MS), both rates being significant (P = 0.0004). Six of the OpS-MS patients had a high level of ANA (1:80 or higher), while levels were high in only three of the other MS patients, showing a significant difference (P = 0.0022). Titres of ANA were significantly higher in OpS-MS patients than in other MS patients (P < 0.0001). There was no relationship between the presence of ANA and age in OpS-MS patients, while patients with were older than those without high ANA levels among other MS patients. ANA-positive rate and titres were significantly higher in OpS-MS patients than in sex- and age-matched other MS patients. These results support the concept that OpS-MS constitutes a distinct subgroup among patients with a clinical diagnosis of MS and may indicate that systemic dysregulation of the inflammatory or immune response is more common in OpS-MS patients; the possible pathogenetic relevance of ANA-associated vasculopathy to some patients with a clinical diagnosis of OpS-MS should be considered.

Adult↗

PubMed1997

Facial palsy in multiple sclerosis.

Facial palsy occurred in 21 (19.6%) of 107 Japanese patients with multiple sclerosis (MS) during a mean follow-up period of 4.3 years. We observed residual signs of facial palsy in five other patients in whom acute onset was confirmed from medical records. Facial palsy began on average 7.6 years after the onset of MS but in five patients (4.7%) was the first symptom of MS, preceding the next MS symptom by 0.5-3 years. Facial palsy was usually associated with other brainstem signs, while two patients showed only facial palsy 1 and 3 years after the onset of MS. Twenty-one (84.0%) of the 25 patients who underwent brain magnetic resonance imaging (MRI) showed brainstem lesions in the pontine tegmentum ipsilateral to the facial palsy. However, the two patients without other symptoms or signs had no apparent causal lesion on MRI, which suggests difficulty in differentiating idiopathic Bell's palsy from MS- associated facial palsy by MRI, although it has an excellent capacity to detect causal lesions of facial palsy associated with MS.

Adult↗

PubMed1997

Localization of 2',5'-oligoadenylate synthetase and the enhancement of its activity with recombinant interferon-alpha A/D in the mouse brain.

Although the expression of 2',5'-oligoadenylate synthetase (2-5AS) is induced by interferon (IFN), low constitutive levels can be detected in animals that have not been treated with IFN. In order to clarify which cells express 2-5AS in the mouse brain, the distribution of this enzyme in the brains of both normal healthy mice and mice treated with recombinant human IFN-alpha A/D was studied by Western blotting and immunohistochemistry, using a specific monoclonal antibody. On the Western blots, the antibody to 42-kD 2-5AS reacted slightly with extracts from the telencephalon, cerebellum, diencephalon, and medulla oblongata of normal mouse brain. 42-kD 2-5AS was predominantly found in the ependymal cells and epithelium of the choroid plexus, and to a lesser degree in neurons and glial cells. Injection of recombinant human IFN-alpha A/D into the left lateral ventricle enhanced the activity of the enzyme in the telencephalon, cerebellum, diencephalon, and medulla oblongata, but did not change the immunohistochemical localization of the enzyme. Direct injection of the IFN into the cortex of the telencephalon enhanced the activity of 2-5AS in all parts of the brain and immunoreactivity was observed in the neurons and glial cells surrounding the injection site. These data indicate that 42-kD 2-5AS activity in the mouse brain is enhanced by the injection of recombinant human IFN-alpha A/D either into the left lateral ventricle or cortex of the telencephalon. Expression of 42-kD 2-5AS in ependymal cells and epithelium of the choroid plexus may prevent viral infections in the brain.

2',5'-Oligoadenylate Synthetase↗

PubMed1997

Regulation by tetracycline of gene expression in Saccharomyces cerevisiae.

A convenient system for the control of gene expression in Saccharomyces cerevisiae was developed. Tetracycline-responsive promoters were constructed by fusing the tetracycline operator (tetO) to the S. cerevisiae HOP1 promoter. When fused to the tetracycline repressor (tetR), trans-activation domains of both GAL4 and HAP4 were capable of promoting transcription from the tetO-HOP1 chimeric promoter, but the tetR-HAP4 fusion activator was the more efficient transcriptional activator. Addition of tetracycline nearly completely repressed activator-dependent transcription from the tetO-HOP1 promoter. Moreover, tetracycline-dependent repression of YEF3, CDC28 and RAM2 expression impaired cell growth. Thus, this system is useful for the elucidation of gene function in S. cerevisiae.

Gene Expression Regulation, Fungal↗

PubMed1997

Immunohistology of skin and oral biopsies in graft-versus-host disease after bone marrow transplantation and cytokine therapy.

BACKGROUND: Early diagnosis of graft-versus-host-disease (GVHD) after bone marrow transplantation is often difficult, particularly when the patients are immunosuppressed by chemotherapy or irradiation. OBJECTIVE: To investigate the influence of cytokines on skin lesions after bone marrow transplantation. METHODS: Biopsy specimens of skin and oral mucosa were obtained from bone marrow transplant patients with GVHD and were subjected to histologic and immunohistochemical examination. RESULTS: Administration of granulocyte-macrophage colony-stimulating factor caused atopic dermatitis-like lesions in two patients, who had infiltration of neutrophils, eosinophils, and lymphocytes around the hair follicles of the skin and no signs of GVHD in other organs. Only patients who were treated with cytokines developed acute GVHD. Immunohistochemical examination of skin biopsies from 18 patients with acute GVHD and 11 patients with chronic GVHD after cyclophosphamide administration or irradiation showed that the maculopapular skin lesions characteristic of acute GVHD contained infiltrates of CD4+ and CD8+ lymphocytes. There was also an increase in numbers of epidermal keratinocytes expressing intercellular adhesion molecule-I and HLA-DR antigens. CONCLUSION: These findings support the involvement of cytokines in GVHD and suggest that immunostaining of skin biopsies may be useful for the early diagnosis of this condition.

Acute Disease↗

PubMed1997

Anticholinergic and calcium antagonistic activities of NS-21 contribute to the inhibition of rat urinary bladder contractions.

1. Pharmacological characteristics of NS-21 and its main metabolite, RCC-36, in the inhibition of rat urinary bladder contractions were investigated both in vitro and in vivo. 2. NS-21 and RCC-36 inhibited muscarinic receptor bindings to rat bladder membranes with [3H]3-quinuclidinyl bezilate (pKi 6.19 and 7.24, respectively), whereas they failed to inhibit the following receptor bindings: adrenergic (alpha 1, alpha 2 and beta), dopaminergic (D1 and D2), adenosine (A1 and A2), histaminergic (H1) and opioid (mu, delta and kappa) receptors. 3. NS-21 and RCC-36 suppressed carbachol-induced contractions of isolated rat detrusor strips in competitive (pA2 6.80 and 7.93, respectively) and noncompetitive (pD'2 5.93 and 5.77, respectively) manners. 4. NS-21 and RCC-36 inhibited CaCl2-induced contractions of rat detrusor strips in the presence of 100 mM K+ (pIC50 6.54 and 5.76, respectively), as well as the 100 mM K(+)-induced 45Ca influx into the isolated bladder strips at > or = 1 microM. 5. Electrical stimulation of the peripheral end of the pelvic nerve in anesthetized rats induced bladder contractions composed of two phases: an initial phasic contraction that was weakly suppressed by atropine, and a tonic contraction that was strongly suppressed by atropine. NS-21 suppressed both contractions to the same degree (ID50 2.65 and 2.19 mg/kg, i.v., respectively). RCC-36 suppressed the tonic contraction (ID50 1.20 mg/kg, i.v.) more markedly than the initial contraction (ID50 7.43 mg/kg, i.v.). 6. These results suggest that NS-21 and RCC-36 suppressed bladder contractions owing to their anticholinergic and calcium antagonistic activities.

Animals↗

PubMed1997

Effects of single and repeated administration of sulthiame on amygdaloid kindled seizures in rats.

In this study, we assessed the anti-convulsive effects of sulthiame (SUL) in amygdaloid (AM) kindled rats. Electrodes were implanted into the left AM of adult male Wistar rats. The animals were kindled at the after-discharge (AD) threshold. Upon completion of kindling, a generalized seizure triggering threshold was determined. The drugs were administered intraperitoneally in rats which reproducibly exhibited generalized convulsions at the near-threshold stimulation. Single administration of SUL (25-200 mg; n = 7-9) reduced the forelimb clonus (FCL) duration, but only the highest dose significantly regressed the secondarily generalized convulsion. During repeated administration of SUL, 50 mg/kg for 8 days, FCL duration was significantly alleviated until the fifth treatment day. With the dose of 200 mg/kg, significant suppression of secondary generalization was noted only until the second test day. On the other hand, significant reductions of FCL and AD duration were preserved afterwards. The anti-convulsive effects of SUL indicated in this study were not comparable to those of other standard anti-epileptic drugs reported from our laboratory.

Amygdala↗

PubMed1997

Neonatal alloimmune thrombocytopenia associated with anti-human platelet antigen-3a antibody.

A sister and brother with neonatal alloimmune thrombocytopenic purpura (NAITP) caused by maternal anti-human platelet antigen (HPA)-3a are reported. The children had transient severe thrombocytopenia in the newborn period, and were treated with intravenous gamma-globulin and platelet concentrates from random donors. Although the sister had intracranial hemorrhage on day 2 postnatally, the development of the child has been normal and no neurological sequelae have been observed. The brother only had bloody stool when the platelet count was low, and did not have severe hemorrhagic manifestations. The diagnosis of NAITP was made by the sera from the mother, which contained anti-HPA-3a antibody directed against platelets of the children. The rate of recurrence might be high in this family, because the father of the patients was found to be homozygous for the HPA-3a gene.

Antigens, Human Platelet↗

PubMed1997

Effect of NS-21, an anticholinergic drug with calcium antagonistic activity, on lower urinary tract function in a rat model of urinary frequency.

BACKGROUND: NS-21 is under development for the treatment of urinary frequency and urinary incontinence. The purpose of this study was to investigate the effects of NS-21 and its active metabolite, RCC-36, on lower urinary tract function in an experimental rat model of urinary frequency. METHODS: Cystometrograms were recorded in anesthetized rats with bilaterally transected hypogastric nerves. All drugs were administered intraduodenally. RESULTS: In sham-operated rats, NS-21 (> or = 50 mg/kg) significantly increased the bladder capacity without significantly decreasing micturition pressure, while RCC-36 (100 mg/kg) significantly increased bladder capacity, and at a dose of > or = 30 mg/kg, also caused a decrease in micturition pressure. This increase in bladder capacity appeared at lower doses of both NS-21 and RCC-36 in the hypogastric nerve-transected rats. Propiverine (100 mg/kg) increased bladder capacity and at > or = 30 mg/kg, decreased micturition pressure in both sham-operated and nerve-transected rats. Oxybutynin (100 mg/kg) and atropine (30 mg/kg) decreased the micturition pressure in both sham-operated and nerve-transected rats without increasing the bladder capacity, while a similar anticholinergic calcium antagonist, terodiline (100 mg/kg) had no effect on bladder capacity in either sham-operated or nerve-transected rats. Flavoxate (500 mg/kg) significantly increased bladder capacity without significantly decreasing micturition pressure in both sham-operated and nerve-transected rats, while 50 mg/kg of verapamil significantly increased bladder capacity without significantly decreasing the micturition pressure in nerve-transected rats. CONCLUSIONS: NS-21 and RCC-36 increased bladder capacity at lower doses in hypogastric nerve-transected rats than in sham-operated rats. Furthermore, NS-21 increased the bladder capacity without suppressing micturition pressure, suggesting that NS-21 may be a more effective therapeutic drug than propiverine, oxybutynin or flavoxate for the treatment of urinary frequency and urinary incontinence.

Animals↗

PubMed1997

[Campylobacter jejuni enteritis in three patients with HIV infection].

Gatrointestinal symptoms, which include diarrhea, are as common as respiratory symptoms in patients with HIV infection. Gastrointestinal symptoms may result from infections, neoplasma, HIV enteropathy or drug toxicity. Three HIV-infected patients admitted to our hospital complaining of diarrhea and fever. We confirmed their diagnosis as Campylobacter jejuni enteritis by bacteriological examination of their feces. All of them had eaten inadequately cooked meat in restaurants before the onset of their enteritis. Their symptoms immediately improved after the administration of antimicrobial agents. One strain of C. jejuni isolated in our cases, however, was resistant to ofloxacin. This case report suggests that we must counsel HIV-infected patients to avoid inadequately cooked food and observe resistant patterns of C. jejuni to antimicrobial agents in Japan in the future.

AIDS-Related Opportunistic Infections↗

PubMed1997

[Analysis of prognosis of bronchopulmonary infectious disease with lung cancer].

Bronchopulmonary infection affects the prognosis of lung cancer patients. Thus, we investigated the relationship between the prognosis of bronchopulmonary infectious diseases and their causative bacteria isolated by transtracheal aspiration (TTA) in lung cancer patients. In the present study, we determined which factor is more predisposing for the outcome of bronchopulmonary infections, the type of causative bacteria or the host nutritional status. A total of 107 lung cancer patients, which consisted of 105 males and 5 females (mean age 67.3 +/- 8.0), were included in this study. The study was conducted from 1981 to 1994. They were classified into the survival group and the deceased group. Causative agents of infection were compared between these 2 groups. S. pneumoniae, alpha-Streptococcus sp., M. catarrhalis, and Neisseria sp. were predominant in organisms isolated from TTA-specimens of lung cancer patients with bronchopulmonary infections, regardless of prognosis. Nutritional status, as determined by serum levels of cholinesterase, albumin, and cholesterol, was poor in the deceased group than in the survival group. These results indicate that the outcome of bronchopulmonary infections in lung cancer patients are affected mainly by the nutritional status of the host.

Aged↗

PubMed1997

[The evaluation of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) level in peripheral blood of patients with chronic lower respiratory tract infection].

In the present study, we assessed the serum level of IL-6 and TNF-alpha by ELISA in patients with chronic lower respiratory tract infection. The serum levels of IL-6 and TNF-alpha of patients in acute exacerbation phase are higher than that of in stable phase. We also classified patients in acute exacerbation phase into two groups according to the microorganism of persistent infection. The serum level of IL-6 and TNF-alpha in the patients with persistent infection with Pseudomonas aeruginosa were higher than that with Haemophilus influenzae. Moreover, the serum level of IL-6 and TNF-alpha were found to be related with malnutrition which assessed by clinical indices such as the serum level of albumin and cholinesterase. The present result suggests that IL-6 and TNF-alpha may have relationship with not only inflammation in airway but also indices of nutrition in patients with chronic lower respiratory tract infection.

Acute-Phase Reaction↗

PubMed1997

[Prognostic analysis of sepsis in patients with lung cancer].

Sepsis is one of the most serious infections occurring in patients with lung cancer. Thus, we determined what is most predisposing factor in prognosis of sepsis in lung cancer patients; the type of causative bacteria, neutropenia or host nutritional status. A total of 27 lung cancer patients with sepsis, which consisted of 23 males and 4 females (mean age 70.7 +/- 6.6), were included in this study. The study was conducted from 1991 to 1995. All subjects were classified into the survival group and the dead group. Staphylococcus aureus or Esherichia coli most frequently isolated from the blood of the patients in the survival group, while either E. coli alone or multiple organisms were predominant in the dead group. Neutropenia did not affect the outcome of sepsis in lung cancer patients. In contrast nutritional status, as determined by serum albumin levels, was closely related to the mortality in septic lung cancer patients. These results predict that the prognosis of sepsis is dependent on nutritional status of lung cancer patients.

Aged↗

PubMed1997

[A case of multiple muscular abscesses of the lower limbs by Staphylococcus aureus after chemotherapy for lung cancer].

A 67-year-old male was admitted to our hospital because of lung cancer and interstitial pneumonia. Cisplatin, vindesie and mitomycin C were administered for treatment of lung cancer. The leucocyte-counts declined to 1700/microliter on the eighth day after the chemotherapy. Though granulocyte colony-stimulating factor was administered, pain in the right thigh and high grade fever developed. Because Staphylococcus aureus was isolated from the blood specimen, piperacillin was administered. But the high grade fever continued and the pain was expanded to the right hip, left hip, thigh and leg. Because a computed tomograph of the lower limbs showed low density areas in bilateral gluteus maximus muscle right adductor magnus muscle, left biceps femoris muscle and left soleus muscle and the culture of an aspirate from abscess of right leg detected S. aureus, multiple muscular abscesses of the lower limbs was confirmed. We changed the antibiotics from PIPC to imipenem/cilastatin and minocycline on nineteenth day after the chemotherapy. His symptoms improved after the change of antibacterial agents. But he died of acute exacerbation of interstitial pneumonia, after about two months of the chemotherapy. Muscular abscesses of the limbs are very rare in Japan. Only four cases with muscular abscess of the limbs were reported in Japan, since 1988. This case suggests that a muscular abscess must be considered in the differential diagnosis of fever in patients with neutropenia.

Abscess↗

PubMed1997

Effect of amino acid and glucose administration during postexercise recovery on protein kinetics in dogs.

To examine the effect of the timing of amino acids (AA) and glucose (G) administration after exercise on protein kinetics, ten dogs fitted with chronic catheters in the artery and the femoral vein ran on a treadmill for 150 min. They were intraportally infused with a solution containing AA and G either right after (E) or 2 h after (L) the exercise. The protein kinetics were estimated using the arteriovenous difference of phenylalanine (Phe) coupled with the [2H5]Phe dilution method. The net balance of Phe across the hindlimb (HL) was negative after exercise. It became positive in E within 15 min after the start of the infusion, and it remained negative in L until the infusion was initiated. The uptake of Phe by the HL during the second half of the infusion period was higher in E than in L (10.9 +/- 6.6 vs. 5.4 +/- 2.3 nmol.kg-1.min-1, P = 0.049). During the infusion, protein synthesis in the HL was higher in E than in L (29.7 +/- 9.6 vs. 22.0 +/- 10.1 nmol.kg-1.min-1, P = 0.028), whereas proteolysis was comparable (18.7 +/- 5.7 vs. 16.5 +/- 11.1 nmol.kg-1.min-1. These results suggest that the early provision of the nutrients after exercise more effectively enhances protein accretion than nutrients administered later.

Amino Acids↗

PubMed1997

Spinocerebellar ataxia type 1 and familial spontaneous pneumothorax.

We report two siblings with spinocerebellar ataxia type 1 (SCA1) who experienced frequent episodes of spontaneous pneumothorax. Radiologic findings indicated underlying degenerative changes in the lungs. This suggests a possible pathophysiologic relationship between SCA1 and familial occurrence of spontaneous pneumothorax.

Adult↗

PubMed1997

Study on histamine related enzyme activities during murine hair cycle.

The beginning of each anagen phase of the hair growth cycle appears to partially repeat the stages in the initial development of the hair cycle, but the regulatory mechanism of the hair cycle is unclear. We have investigated the levels of histamine related enzyme activities in the third hair cycle period of C3H mouse after depilation. The level of histidine decarboxylase activity increased just after depilation treatment and returned to the normal level within two weeks: this change was relevant to histamine content as we have previously reported. This result suggests that the histamine synthesising enzyme, histidine decarboxylase, activity may be involved in the distinctive process of hair re-growth, in particular, the initiation of the anagen phase.

Animals↗

PubMed1997

Establishment of a new myeloid cell line with i(17q) as the sole chromosomal anomaly from the bone marrow of a patient with myelodysplastic syndrome.

A new myeloid cell line, MTO-94, was established from the bone marrow of a patient with myelodysplastic syndrome (MDS). MTO-94 cells matured in culture medium without the addition of growth factors, and yielded neutrophils with pseudo-Pelger Huët anomaly or hypersegmentation until 6 months. Ten months after the start of cell cultivation, MTO-94 consisted of myeloblasts. Surface phenotypes were as follows: CD7 90.3%, CD13 99.6%, CD33 75.6%, HLA-DR 96.3% and CD34 0.9%. The karyotype was 46, XY i(17q). The proliferation of MTO-94 cells was enhanced by rhIL-3, G-CSF, rhGM-CSF and rhSCF but not by rhIL-6 and erythropoietin. MTO-94 cells with i(17q) might be useful in the study of biological aspects of not only MDS, but also hematological malignancies with i(17q) as the sole chromosomal anomaly.

Aged↗