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Biomedical subjects

M Hara

Publications and source records attributed to M Hara.

At least 433 records · Page 24Linked to original sources
PubMed1997

Structural and biochemical basis for the UVB-induced alterations in epidermal barrier function.

Ultraviolet light (UVR) induces a myriad of cutaneous changes, including delayed disruption of the permeability barrier with higher doses. To investigate the basis for the UVB-induced barrier alteration, we assessed the epidermal lamellar body secretory system at various time points before and after barrier disruption with a single high dose of UVB (7.5 MED) to murine epidermis. Morphological data were correlated with changes in epidermal proliferation and lipid synthesis, indicative of lamellar body generation. Twenty-four hours following UVB, the stratum corneum (SC) is normal, but a layer of abnormal, vacuolated, and lamellar body (LB)-deficient cells is present, immediately beneath the stratum granulosum (SG)/SC interface. Immediately subjacent to this band of damaged cells, normal keratinocytes that contain intact LBs are present. By 72 h, concomitant with the appearance of a barrier abnormality, extensively damaged cells persist at the SC/SG interface, and abnormal lamellar membrane structures appear in the lower SC. Upper stratum spinosum (SS) and lower SG cells appear normal, with increased numbers of LBs. A barrier abnormality is still present at 96 h, in association with membrane abnormalities in the lower SC interstices, but up to four normal appearing, subjacent SG cell layers are present. By 120 h, accelerated LB formation and precocious LB extrusion occur throughout the thickened SG; normal lamellar membranes are present in the lower SC; and barrier recovery is almost complete. Whereas, epidermal synthesis of the major barrier lipid species (i.e., cholesterol, fatty acids, and ceramides, including acylceramides) is reduced or unchanged at 24 and 48 h, it increases significantly 72 h after exposure to UVB. Therefore, the delayed disruption of the permeability barrier following acute UVB exposure results from the arrival of a band of lamellar body-incompetent (i.e., damaged) cells at the SG/SC interface. The subsequent, rapid recovery of the barrier, in turn, results from compensatory hyperplasia of subjacent, undamaged SS/SG cells, generating increased numbers and contents of LB. These results underscore the critical role of the stratum compactum in mediating barrier function, and suggest that beneficial therapeutic effects of UV exposure may be due to enhanced lipid production and barrier regeneration.

Acyltransferases↗
PubMed1997

Effect of beta 2-agonists on histamine-induced airway microvascular leakage in ozone-exposed guinea pigs.

beta 2-adrenergic agonists exhibit antipermeability effects in the airways. However, it is not known whether beta 2-agonists have this beneficial effect in airway mucosa that is already inflamed. We evaluated the effects of two inhaled beta 2-agonists, salbutamol and formoterol, on the histamine-induced bronchoconstriction and plasma extravasation in the airways of guinea pigs with or without ozone exposure. Total pulmonary resistance (RL) was measured before and after histamine inhalation in anesthetized animals that were pretreated with inhaled salbutamol, formoterol, or saline. Plasma extravasation in the airways was measured using Evans blue dye. In the control animals not exposed to ozone, salbutamol and formoterol each significantly reduced both the histamine-induced bronchoconstriction and the plasma extravasation in the trachea and main bronchi. In the ozone-exposed animals, the increase in RL after histamine was greater than that in control animals. Salbutamol and formoterol each significantly reduced histamine-induced bronchoconstriction, even in the ozone-exposed animals. Salbutamol did not affect the histamine-induced plasma extravasation, whereas formoterol reduced the plasma extravasation in the main bronchi, but not in the trachea, of the animals exposed to ozone. These results suggest that the anti-inflammatory properties of formoterol in inflamed airways may contribute to the beneficial effects in the treatment of airway inflammation.

Adrenergic beta-Agonists↗
PubMed1997

Ocular melatonin rhythms in the goldfish, Carassius auratus.

Ocular melatonin rhythms in the goldfish were studied and compared to those in the pineal organ and plasma. Under light:dark (LD) of 12 h light:12 h dark, melatonin contents in the eye as well as the pineal organ and plasma exhibited clear day-night changes with higher levels at mid-dark than at mid-light. However, melatonin contents in the eye at mid-light and mid-dark were approximately 100 and 9 times greater than those in the pineal organ, respectively. Day-night changes of ocular melatonin persisted after pinealectomy, which abolished those in plasma melatonin under LD 12:12. Ocular melatonin contents in the pinealectomized fish at mid-light were significantly higher than those in the sham-operated control. Under constant darkness (DD), circadian melatonin rhythms were observed in the eye but damped on the 3rd day, whereas plasma melatonin rhythms generated by the pineal organ persisted for at least 3 days. Under constant light, ocular melatonin contents exhibited a significant fluctuation with a smaller amplitude than that under DD, whereas plasma melatonin remained at low levels. These results indicate the involvement of LD cycles, a circadian clock, and the pineal organ in the regulation of ocular melatonin rhythms in the goldfish.

Animals↗
PubMed1997

3,5,3'-Triiodo-L-thyronine potentiates all-trans-retinoic acid-induced apoptosis during differentiation of the promyeloleukemic cell HL-60.

Although the programmed cell death mediated by thyroid hormone is not well evaluated in mammalian cells, thyroid hormone plays a crucial role in differentiation of the cells during the metamorphosis of Xenopus, suggesting that thyroid hormone has the potential ability to induce the apoptosis. To investigate the thyroid hormone-inducible apoptosis, we cultured HL-60 cells with various amounts of all-transretinoic acid (RA) and L-T3. T3 alone did not induce the apoptosis of the cells. T3, however, suppressed the proliferation of cells in the presence of RA. DNA ladder and microscopical examination showed that the reduction of cell number was due to the apoptosis induced by RA. These findings suggested that T3 affects the apoptotic process during the differentiation of HL-60 cells by RA. T3-inducible apoptosis may require the factors augmented by RA in HL-60 cells.

Apoptosis↗
PubMed1997

Orientation of photosynthetic reaction center reconstituted in neutral and charged liposomes.

The photosynthetic reaction center from the photosynthetic bacterium Rhodobacter sphaeroides was reconstituted into neutral, positively charged, or negatively charged liposomes. About 70% of photosynthetic reaction centers were reconstituted in the proteoliposomes exposing their H-subunit outside with positively charged lipids while only 30-40% of them were in the same topological orientation with neutral or negatively charged lipids.

Cytochrome c Group↗
PubMed1997

Multiple endocrine neoplasia type 1 is not rare in Japan.

Multiple endocrine neoplasia type 1 (MEN 1) is rarely reported in Japanese and other oriental populations. To examine if there is a racial difference in the prevalence of MEN 1, we initiated extensive work on patients with endocrine tumors for additional lesions, and annual screening of family members of affected patients. In a four-year study, eleven asymptomatic patients were found by family screening, and the number of patients with MEN 1 in our clinics increased from 16 to 38. Estimated prevalence of MEN 1 was no less than 0.018/1000. MEN 1 may not be as rare as had been thought in Japanese, and the prevalence of MEN 1 in Japanese would not be significantly different from that of Caucasians. Systemic surveillance and extensive screening of family members are required for early detection and management of patients.

Adolescent↗
PubMed1997

Sclerosing cholangitis associated with hypereosinophilic syndrome.

A 15-year-old male with hypereosinophilic syndrome was admitted to our hospital because of general malaise and abnormal liver function tests. Endoscopic retrograde cholangiopancreatography demonstrated bile duct changes consistent with primary sclerosing cholangitis. The patient's liver profile tests returned to normal after treatment with prednisolone and ursodeoxycholic acid. In this case, eosinophils might have played an important role in the pathogenesis of the bile duct lesion.

Adolescent↗
PubMed1997

[An autopsy case of anti-neutrophil cytoplasmic antibodies associated vasculitis accompanied by autoimmune hepatitis and hepatocellular carcinoma].

Here we report an autopsy case with anti-neutrophil antibodies (ANCA) associated vasculitis accompanied by autoimmune hepatitis and hepatocellular carcinoma. A 69-year-old woman was admitted to Tokyo Metropolitan Ohtsuka Hospital in October 1995 because of leg edema. She had presented cough in 1990 and diagnosed as interstitial pneumonia, esophageal varices and liver chirosis. On admission, laboratory data showed mild anemia, hypoproteinemia, and marked gammagloblinemia. IgM-HA antibody, HBs antigen, HBs antibody, HCV antibody and HDV antibody were negative. Anti-nuclear antibody, anticentromere antibody, anti-neutrophil cytoplasmic antibody against myeloperoxidase and cathepsin G (MPO-ANCA and cathepsin G), rheumatoid factor and direct coombs test were positive. Serum level of AFP and CEA were elevated. Ultrasonography and computed tomography of abdomen scowed liver chirosis and tumor in left lobe of liver. The diagnosis of liver chirosis based on autoimmune hepatitis and Interstitial pneumonia was made with clinical course, laboratory findings and radiographic findings although liver biopsy was not performed. She complained of bloody stool due to ulcer of the large intestine, and died of liver failure which progressed rapidly. The autopsy findings detected that pulmonary fibrosis, liver fibrosis with multiple hepatocellular carcinoma, necrotizing crescentic glomerulonephritis, and vasculitis of small artery inn colon. This was the first report of MPO-ANCA associated vasuculitis complicated with autoimmune hepatitis and hepatocellular carcinoma. Clinical significance of ANCA and immunogenetic background of these diseases were discussed.

Aged↗
PubMed1997

[Cyclophosphamide pulse therapy for refractory rheumatic diseases].

We studied the efficacy of cyclophosphamide pulse therapy (CYP) for refractory rheumatic diseases except for lupus nephritis. Thirty-five patients were included in all, that is 9 patients with systemic lupus erythematosus (SLE), 10 with rheumatoid arthritis (RA), 7 with polymyositis/dermatomyositis (PM/DM), 2 with progressive systemic sclerosis (PSS), 2 with anti-phospholipid antibody syndrome (APS), 1 with mixed connective tissue disease (MCTD), 1 with juvenile rheumatoid arthritis (JRA), 1 with Behcet's disease (BD), 1 with Wegener's granulomatosis (WG) and 1 with allergic granulomatous angiitis (AGA). Moderate to marked improvement was noted in 4 patients with SLE (2 with CNS-lupus and 2 with vasculitis), 7 with RA (2 with interstitial pneumonia:IP, 2 with vasculitis and 2 with refractory arthritis), 4 with PM/DM (2 with IP and 2 with refractory myositis), 1 PSS with IP, 2 APS with thrombocytopenia, 1 JRA with vasculitis and BD with CNS disturbance. On the other hand, adverse reactions were observed in 9 out of 35 patients (25.8%). CYP should apply in the treatment for such refractory rheumatic diseases as CNS disturbance, vasculitis, IP and autoimmune thrombocytopenia.

Arthritis, Rheumatoid↗
PubMed1997

Mutations in the hepatocyte nuclear factor-1alpha/MODY3 gene in Japanese subjects with early- and late-onset NIDDM.

Recent studies have shown that mutations in the hepatocyte nuclear factor (HNF)-1alpha gene are the cause of maturity-onset diabetes of the young type 3 (MODY3). We have screened 193 unrelated Japanese subjects with NIDDM for mutations in this gene: 83 with early-onset NIDDM (diagnosis at <30 years of age) and 110 with late-onset NIDDM (diagnosis > or = 30 years of age). All of the members of the latter group also had at least one sibling with NIDDM. The 10 exons, flanking introns, and promoter region were amplified using polymerase chain reaction and were sequenced directly. Mutations were found in 7 of the 83 (8%) unrelated subjects with early-onset NIDDM. The mutations were each different and included four missense mutations (L12H, R131Q, K205Q, and R263C) and three frameshift mutations (P379fsdelCT, T392fsdelA, and L584S585fsinsTC). One of the 110 subjects with late-onset NIDDM was heterozygous for the missense mutation G191D. This subject, who was diagnosed with NIDDM at 64 years of age, also had a brother with NIDDM (age at diagnosis, 54 years) who carried the same mutation, suggesting that this mutation contributed to the development of NIDDM in these two siblings. None of these mutations were present in 50 unrelated subjects with normal glucose tolerance (100 normal chromosomes). Mutations in the HNF-1alpha gene occur in Japanese subjects with NIDDM and appear to be an important cause of early-onset NIDDM in this population. In addition, they are present in about 1% of subjects with late-onset NIDDM.

Age Factors↗
PubMed1997

P300 and cerebral blood flow before and after TRH in olivopontocerebellar atrophy.

Ten cases of olivopontocerebellar atrophy (OPCA) (mean age 56 +/- 9 years) and 8 healthy controls (mean age 58 +/- 9 years) were studied. The P300 was measured with a Synax 1100 evoked potential recorder and the regional cerebral blood flow was measured using the stable xenon computed tomography method. The P300 latency was significantly longer in the OPCA group than in the healthy control group. The P300 latency after the intravenous infusion of thyrotropin releasing hormone (TRH) in the OPCA group was significantly shorter than that before the intravenous infusion of TRH. The blood flows in all the measured areas (the cerebellar cortex, the cerebellar white matter, the brainstem, the thalamus, the basal ganglia, the frontal lobe cortex and the frontal lobe white matter) were significantly lower in the OPCA group than in the healthy control group. The blood flows in the cerebellar cortex and in the frontal lobe cortex after the intravenous infusion of TRH were significantly higher than those before the intravenous infusion of TRH. The prolongation of P300 latency in the OPCA group suggests that subclinical disturbance in recognition function is present in OPCA and may be related to the blood flow decrease outside the cerebellum.

Aged↗
PubMed1997

[Randomized prospective trial of gentian violet with dibutyryl cAMP and povidone-iodine with sugar as treatment for pressure sores infected with methicillin-resistant Staphylococcus aureus in elderly patients].

A randomized prospective study was done to evaluate the two treatments for pressure sores infected with methicillin-resistant Staphylococcus aureus in elderly patients: Gentian violet plus dibutyryl cAMP (GVcAMP, n = 8) and povidone-iodine plus sugar (IS, n = 11). Age, underlying diseases, and nutritional status did not differ between the two groups. Specimens were obtained biweekly from the pressure sores and were cultured. The percentage of culture dishes with no methicillin-resistant S. aureus was 93% for the patients given GVcAMP, but only 74% for those given IS (p < 0.01). By the 14th week after the start of treatment, the mean area of the pressure sores in the GVcAMP group had decreased to 45% of the area at the start of treatment. In the IS group, the decrease was smaller to 56% of the area before treatment. No local or systemic adverse effects occurred in either group. GVcAMP is useful to treat pressure sores infected with methicillin-resistant S. aureus.

Aged↗
PubMed1997

Co-secretion of parathyroid hormone and parathyroid-hormone-related protein via a regulated pathway in human parathyroid adenoma cells.

Parathyroid-hormone-related protein (PTHrP) is widely expressed not only in malignant tumors but also in both epithelial and nonepithelial cells of normal tissues. Secreted PTHrP is suspected to act as a paracrine or autocrine regulator. However, little is known about its secretory pathway. To cast light on this question, we studied the intracytoplasmic distribution of parathyroid hormone (PTH) and PTHrP immunohistochemically and immunoelectron microscopically in 10 surgically resected parathyroid adenomas. Double immunostaining was performed using anti-PTH antibody and a newly established anti-PTHrP antibody to reveal the relationship between their two distributions. Additional examination by cell immunoblot assay was performed to determine whether both PTH and PTHrP are secreted simultaneously. Both PTH and PTHrP were actually secreted from individual parathyroid cells simultaneously on cell immunoblot assay. Immunohistochemically, there were two different types of adenoma cells, i.e., one positive only for PTH and the other positive for both PTH and PTHrP. PTH was distributed linearly or fine granularly along the cytoplasmic membrane, whereas PTHrP was distributed diffusely or coarse granularly in the cytoplasm. The intracytoplasmic distributions of PTH and PTHrP often overlapped. Immunoelectron microscopical examination demonstrated that PTHrP co-localized with PTH in the same secretory granules. The results clearly demonstrated that PTHrP can be co-secreted with PTH via a regulated pathway using secretory granules.

Adenoma↗
PubMed1997

[Syndrome of inappropriate secretion of antidiuretic hormone associated with miliary tuberculosis].

An 82-year-old man with the chief complaint of anorexia was referred on suspicion of pulmonary tuberculosis. He had undergone thyroidectomy because of thyroid cancer 5 years ago, had taken levothyroxine sodium, and had kept plasma level of thyroidal hormone within normal range. He had never pointed out hyponatremia. On laboratory findings on admission, serum natrium level was 125 mEq/l. A chest X-ray film showed the infiltration in both lower lung fields, and a chest CT scan revealed a miliary pattern in both lungs. Tubercle bacilli were detected from the sputum by the Ziehl-Neelsen staining. Antituberculous drugs were started. On 5th hospital day, he developed consciousness disturbance, and the serum level of natrium and osmolarity was 103 mEq/l and 250 mOsm /kgH2O, respectively, while plasma ADH level was increased to 5.9 pg/ml, and urine level of natrium and osmolarity was 123 mEq/l and 394 mOsm/kgH2O, respectively. His mental disturbance and hyponatremia gradually improved by supplementing NaCl. We diagnosed this case as SIADH associated with miliary tuberculosis. SIADH should be considered when hyponatremia was occurred in the case of miliary tuberculosis.

Aged↗
PubMed1997

[Arterial-venous carbon dioxide tension difference after hypothermic cardiopulmonary bypass].

Arterial-venous carbon dioxide tension difference (Pv-aCO2) is known to become high after severe hemorrhage shock and resuscitation. We hypothesized that Pv-aCO2 might be high after cardiac surgery because of the oxygen debt occurred during hypothermic cardiopulmonary bypass (CPB). Blood pressure, cardiac index, hemoglobin, the arterial and mixed venous blood gases were repeatedly measured every 6 hours for 24 hours following cardiac surgery in 60 adult patients who underwent hypothermic CPB. Immediately after the surgery, Pv-aCO2 was extremely high, then gradually decreased to within normal ranges 12 hours later (8.0 +/- 2.9 mmHg vs 5.9 +/- 3.1 mmHg. p < 0.01). Factors which significantly correlated to Pv-aCO2 were cardiac index, oxygen delivery, minimum rectal temperature and duration of CPB. Oxygen debt during hypothermic CPB might cause significantly high Pv-aDO2. At least 12 hours were necessary to recover from anaerobic status to physiological condition.

Adult↗