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Biomedical subjects

A Matsushita

Publications and source records attributed to A Matsushita.

At least 19 recordsLinked to original sources

Definitive experimental evidence for two-band superconductivity in MgB2.

The superconducting-gap of MgB2 has been studied by high-resolution angle-resolved photoemission spectroscopy. The results show that superconducting gaps with values of 5.5 and 2.2 meV open on the sigma band and the pi band, respectively, but both the gaps close at the bulk transition temperature, providing a definitive experimental evidence for the two-band superconductivity with strong interband pairing interaction in MgB2. The experiments validate the role of k-dependent electron-phonon coupling as the origin of multiple-gap superconductivity as well as the high transition temperature of MgB2.

Journal Article↗

Subcutaneous phaeohyphomycosis caused by Veronaea botryosa in the People's Republic of China.

The second case of phaeohyphomycosis caused by Veronaea botryosa in China, in a 12-year-old boy from Jiangsu Province, is presented. Based on direct examination of the scrapings from crusted lesions; histologic examination of the biopsy tissue showing septate, phaeoid hyphal elements; and the culture exhibiting sympodial, conidiogenous cells producing predominantly two-celled, cylindric conidia, the etiologic agent was identified as V. botryosa.

Child↗

Expression of the 67-kDa elastin receptor in perforating skin disorders.

BACKGROUND: Perforating skin dermatoses include elastosis perforans serpiginosa (EPS), reactive perforating collagenosis, Kyrle's disease and perforating folliculitis. In addition to these four diseases, an acquired form of perforating dermatosis associated with diabetes mellitus and/or chronic renal failure has been reported for which the term acquired perforating dermatosis (APD) was proposed. The molecular mechanism of transepidermal elimination of dermal components in perforating skin dermatoses remains unclear. We recently demonstrated that the 67-kDa elastin receptor can be detected in the epidermis eliminating altered elastic fibres in EPS, suggesting that the elastin-keratinocyte interaction may play a role in transepidermal elimination in EPS. OBJECTIVES: To determine whether the 67-kDa elastin receptor is involved in other perforating diseases. METHODS: Paraffin-embedded skin specimens from new cases of EPS (n = 2), APD (n = 15) and perforating granuloma annulare (PGA; n = 2) were studied immunohistochemically using a specific antibody to the 67-kDa elastin receptor. In one case of EPS, two different sites from a single lesion, a central atrophic area and a peripheral keratotic area, were studied. RESULTS: Expression of the elastin receptor was detected in the epidermis surrounding the elastic materials in both cases of EPS. The elastin receptor was not detected in the central inactive area, whereas it was expressed strongly in the peripheral keratotic active area. The elastin receptor was also detected in three of 15 cases of APD in which a few elastic fibres were found in the eliminated dermal materials. In one case of APD, the elastin receptor was not detected in spite of the presence of a few elastic fibres in the eliminated materials. The elastin receptor was not detected in either case of PGA. CONCLUSIONS: Expression of the elastin receptor in EPS was seen in both cases studied and was dependent on the stage of the lesion. Expression of the elastin receptor in APD appeared to be related to the amount of elastic fibres in the eliminated materials. Thus, expression of the elastin receptor in perforating skin disorders may depend on the stage of the lesion and/or the content of elastic fibres in the dermal materials being eliminated.

Adult↗

Antitumor effect of a new selective matrix metalloproteinase inhibitor, MMI-166, on experimental pancreatic cancer.

The antitumor effect of a new matrix metalloproteinase inhibitor, MMI-166, which is a selective inhibitor of MMP-2 and -9, was examined in the hamster pancreatic cancer cell line PGHAM-1. In vitro, MMI-166 inhibited the gelatinase activity of MMP-2 and -9 derived from PGHAM-1 cells, and dose-dependently inhibited invasion of PGHAM-1 through a basement membrane-like barrier. MMI-166 showed no apparent cytotoxicity to PGHAM-1 cells in culture at 100 microgram/ml. MMI-166 (200 mg/kg) or vehicle were administered orally, once daily, from day 1 until day 21 after implantation in the orthotopic implantation model of PGHAM-1. MMI-166 significantly reduced the incidence of liver surface metastasis from 66.7% to 20.0%, and it reduced the number of liver surface metastases per animal from 6.17 to 2.00, but this reduction was not significant. MMI-166 significantly reduced the volume of pancreatic tumors from 718.3 +/- 220.0 mm(3) to 222.8 +/- 85.4 mm(3). Treatment of pancreatic tumors with MMI-166 caused a significant reduction in the microvessel density from 37.90 +/- 10.18/mm(2) to 16.16 +/- 3.15/mm(2) and a significant increase in apoptotic index from 1.75 +/- 0.41% to 3.96 +/- 0.38%, but there was no significant difference between tumor cell proliferation in the MMI-166-group and the control group. These results showed that selective MMP inhibition could limit both cancer spread and angiogenesis in pancreatic cancer. The selective MMP-2 and -9 inhibitor MMI-166 may be of therapeutic use in the treatment of pancreatic cancer because of its inhibitory effect on invasion and angiogenesis.

Animals↗

Involvement of the NUP98 gene in a chromosomal translocation t(11;20)(p15;q11.2) in a patient with acute monocytic leukemia (FAB-M5b).

We report here a case of acute monocytic leukemia (M5b subtype according to the French-American-British [FAB] classification) with chromosomal translocation t(11;20)(p15;q11.2). Fluorescence in situ hybridization analysis with a probe for the NUP98 gene, which is located at chromosome band 11p15, showed that the probe hybridized to both derivative chromosomes 11 and 20 as well as to the remaining normal chromosome 11, indicating that the NUP98 gene was split and involved in this translocation. This is the first report of t(11;20)(p15;q11.2) involving the NUP98 gene in overt leukemia.

Aclarubicin↗

Malignant hyperthermia in a patient with Graves' disease during subtotal thyroidectomy.

We report the case of a 31-year-old man with Graves' disease who manifested malignant hyperthermia during subtotal thyroidectomy. His past medical history and family history were unremarkable. Before surgery, his condition was well controlled with propylthiouracil, beta-adrenergic blocker and iodine. During the operation, anesthesia was induced by intravenous injection of vecuronium and thiopental, followed by suxamethonium for endotracheal intubation. Anesthesia was maintained with nitrous oxide and sevoflurane. One hour after induction of anesthesia, his end tidal carbon dioxide concentration (ET(CO2)) increased from 40 to 50 mmHg, heart rate increased from 90 to 100 beats per min and body temperature began to rise at a rate of 0.3 degrees C per 15 min. Suspecting thyroid storm, propranolol 0.4 mg and methylprednisolone 1,500 mg were administered, which, however, had little effect. Despite the lack of muscular rigidity, the diagnosis of malignant hyperthermia was made based on respiratory acidosis. Sevoflurane was discontinued and dantrolene was given by intravenous bolus. Soon after the treatment, ET(CO2), heart rate and body temperature started to fall to normal levels. His laboratory findings showed abnormally elevated serum creatine phosphokinase and myoglobin but normal thyroid hormone levels. Since dantrolene is efficacious in thyrotoxic crisis and malignant hyperthermia, an immediate intravenous administration of dantrolene should be considered when a hypermetabolic state occurs during anesthesia in surgical treatment for a patient with Graves' disease.

Acidosis, Respiratory↗

Effects of dietary lipids on renal function of aged rats.

Normal aging is accompanied by renal functional and morphological deterioration and dietetic manipulation has been used to delay this age-related decline. We examined the effects of chronic administration of diets containing 5% lipid-enriched diet (LD, w/w) on renal function of rats at different ages. Three types of LD were tested: canola oil, fish oil and butter. Mean systemic tail-cuff blood pressure and glycemia remained within the normal range whatever the age and the diet of the animals. Proteinuria began to rise from the 8th month in the groups ingesting LD, while in the control group it increased significantly (above 10 mg/24 h) only after the 10th month. With age, a significant and progressive decline in glomerular filtration rate (GFR) and renal plasma flow was observed in the LD groups but after 6 months of lipid supplementation, the decline in these parameters was more marked in the butter and fish oil groups. By the 18th month, the lowest GFR level was observed in the group ingesting the butter diet (2.93 +/- 0.22 vs 5.01 +/- 0.21 ml min(-1) kg(-1) in control, P<0.05). Net acid excretion, evaluated in 9- and 18-month-old rats, was stimulated in the fish oil group when compared both to control and to the other two LD groups. These results suggest that even low levels of LD in a chronic nutritional regimen can modify the age-related changes in renal function and that the impact of different types of lipid-supplemented diets on renal function depends on the kind of lipid present in the diet.

Age Factors↗

One week pulse therapy with itraconazole (200 mg day-1) for onychomycosis. Evaluation of treatment results according to patient background.

We investigated background factors of patients that affect the response of onycomycosis to pulse therapy with itraconazole. The regimen used in this study involved administering 200 mg of itraconazole orally on a daily basis for 1 week as one pulse, which is half of the normally recommended dose. The number of pulses was fixed at one per month, and altered in accordance with improvements in the infected nails and/or the patients' request. Patient background (n = 63) including sex, age, occupation, duration of the disease, site of lesion (fingernail, toenail), number of affected nails, clinical types, severity of thickening, presence or absence of pathogens, the presence or absence of underlying diseases such as adult onset diseases, turbidity of the target nails before therapy and the number and duration of pulses was investigated. The efficacy of the therapy was evaluated after 12 months. A complete cure was judged to have taken place if an entirely healthy nail plate re-grew in place of the diseased nail, whereas lack of success was defined as the persistence of lesions beyond the designated time period. The average number and duration of pulses were 4.7 +/- 3.2 times over 5.6 +/- 4.3 months, respectively. The rate of complete cure was 62%. Factors in the patients' background that were judged to have an influence on treatment results were the relative duration of the disease, the number of affected nails, and severity of thickening. With regard to the efficacy of the therapy in terms of the number and duration of pulses, 78% of 23 patients who were given pulse therapy two to six times during a course of 2 to 6 months achieved total cure.

Administration, Oral↗

Cutaneous zygomycosis: a case report and review of Japanese reports.

A 69-year-old man, a carpenter with idiopathic thrombopenic purpura and interstitial pneumonia, was treated with steroid pulse therapy and antibiotics. On the seventh day of steroid therapy, a conglomeration of papules, vesicles and pustules appeared in an area of the left buttock in contact with his napkin. In a Parker KOH specimen of the crust of the lesion, many non-septate hyphae were seen, and culture of material obtained by biopsy yielded Rhizopus microsporus var. microsporus. Ketoconazole cream was applied topically for 1 week, and the exanthema healed. After the third month of inpatient treatment, the patient's overall condition had returned to normal, and he was discharged. Cutaneous zygomycosis is a rare disease, and only 19 cases have been reported in Japan. Its characteristics, as reported in these cases, have been collected and collated.

Aged↗

Compressibility and polygonization of single-walled carbon nanotubes under hydrostatic pressure

Single-walled carbon nanotubes show linear elasticity under hydrostatic pressure up to 1.5 GPa at room temperature. The volume compressibility, measured by in situ synchrotron x-ray diffraction, has been determined to be 0.024 GPa (-1). Theoretical calculations suggest that single-walled carbon nanotubes are polygonized when they form bundles of hexagonal close-packed structure and the intertubular gap is smaller than the equilibrium spacing of graphite (002) (d = 3.35 A). It has also been determined that the deformation of the trigonal nanotube lattice under hydrostatic pressure is reversible up to 4 GPa, beyond which the nanotube lattice is destroyed.

Journal Article↗

Colocalization of pinopsin with two types of G-protein alpha-subunits in the chicken pineal gland.

Pinopsin is a photoreceptive molecule present in the outer segments of chicken pinealocytes. In this paper, the localization of alpha-subunits of G-proteins, rod transducin (Gt1) and Gq/11, was examined by immunoelectron microscopy to investigate whether these G-proteins colocalize with pinopsin in the outer segments. Ultrathin sections of the chicken pineal gland were double-immunolabeled with antibodies to pinopsin and either Gt1alpha or Gq/11alpha. As shown previously, the outer segments around the follicular lumen exhibited divergent morphology with ciliary, bulbous, or lamellate shapes, and most of them displayed pinopsin immunoreactivity. The majority (>90%) of pinopsin-immunopositive outer segments were labeled by anti-Gt1alpha and/or anti-Gq/11alpha antibodies. Application of double-immunolabeling to serial sections demonstrated that a large number of the pinopsin-immunopositive outer segments contained both Gt1alpha and Gq/11alpha immunoreactivities. These results suggest that Gt1alpha and Gq/11alpha are functionally coupled with light-activated pinopsin within a single outer segment.

Animals↗

The cytotoxic effects of bile acids in crude bile on human pancreatic cancer cell lines.

Pancreatic cancer frequently causes extrahepatic cholestasis. To identify the direct effects of bile acids in jaundiced serum on pancreatic cancer, the proliferation of PANC-1 and MIA PaCa-2 cells as well as the ultrastructural alteration of PANC-1 cells cultured in crude bile modified media were studied. The growth of these cells in the RPMI-1640 media with or without 1%, 2%, and 4% of the refined crude bile was assessed after 48 and 96 h of incubation. The ultrastructure of PANC-1 cells was investigated by scanning and transmission electron microscopy after 24 and 48 h of incubation. The proliferation of both cell lines in the bile-treated media was greatly inhibited. The inhibitory rates of bile on PANC-1 ranged from 24.1% +/- 3.3% to 66.9% +/- 6.6% (P < 0.01) and those on MIA PaCa-2 ranged from 16.7% +/- 3.8% to 50.7% +/- 5.5%. (P < 0.01). When the bile-added media were replaced, the cells were able to restore their proliferating ability. The PANC-1 cells incubated in the bile-supplied media indicated that the mirovilli, mitochondria, and other organelles had thus been injured. These results suggest that bile acids appear to inhibit the proliferation of PANC-1 and MIA PaCa-2 cells, and the probable inhibitory mechanism is mainly considered to be due to the cytotoxicity of such bile acids.

Bile Acids and Salts↗

Differences between the silencing-related properties of the extreme carboxyl-terminal regions of thyroid hormone receptors alpha 1 and beta 1.

Human thyroid hormone receptor (TR) is encoded by two distinct genes, TR alpha and TR beta. TR heterodimerizes with retinoid X receptor (RXR) and binds efficiently to the thyroid hormone (T(3)) response element (TRE) of target genes. In the absence of T(3), unliganded TR suppresses the basal promoter activity of positively regulated genes (silencing). Silencing mediator for retinoid and thyroid hormone receptors (SMRT) and nuclear receptor co-repressor (N-CoR) interact with unliganded TR and function as corepressor proteins. Previously, we found beta F451X with carboxyl (C)-terminal 11-amino acid deletion had stronger silencing potency than wild-type TR beta 1 and beta E449X with C-terminal 13-amino acid deletion on a subset of TREs. In the present study, to assess the isoform-specific effects of the C-terminal truncations on TR silencing, we constructed two mutant TR alpha 1s (alpha F397X and alpha E395X) with the same respective C-terminal truncations as beta F451X and beta E449X and analysed their silencing activities. Unlike beta F451X and beta E449X, alpha F397X and alpha E395X showed similarly stronger silencing potency than wild-type TR alpha 1. We further studied the abilities of wild-type and the mutant TR beta 1s and alpha 1s on RXR and co-repressor binding by a two-hybrid interference assay. beta F451X had significantly stronger abilities to bind to RXR and SMRT than did wild-type TR beta 1 and beta E449X. In contrast, wild-type TR alpha 1, alpha F397X and alpha E395X showed similar abilities to bind to RXR and SMRT. beta E449X and alpha E395X, which have identical C-terminal truncation, showed less ability to bind to N-CoR than did wild-type TR beta 1 and beta F451X and wild-type TR alpha 1 and alpha F397X respectively. These results indicate that an identical C-terminal truncation gives rise to different effects on TR beta 1 and alpha1 with respect to silencing potency, RXR binding and SMRT binding. The difference in the silencing potency among wild-type TR beta 1, beta F451X and beta E449X correlated well with the difference in the ability to bind co-repressor SMRT.

Animals↗

Very strong correlation between dominant negative activities of mutant thyroid hormone receptors and their binding avidity for corepressor SMRT.

The syndrome of resistance to thyroid hormone (RTH) is an inherited disorder involving a mutation of the thyroid hormone receptor (TR) gene. Mutant (m) TR inhibits wild-type (wt) TR functions in a dominant negative manner, and this dominant negative effect (DNE) is a crucial factor in RTH pathogenesis. The molecular mechanism of the DNE is still unclear, although several possibilities (including competition between wt- and mTRs at the T(3) response element (TRE), sequestration of TR-associated protein(s) and titration out of functional TR) have been considered. Here we report that the DNE of mTRs is strongly correlated with their binding avidity for the retinoid X receptor (RXR), and especially for corepressor SMRT (silencing mediator for retinoid and thyroid hormone receptor), but not for the nuclear receptor corepressor, NCoR. The DNE of six natural TRs and four artificially constructed mTRs was assayed using a TR reporter gene containing TRE-DR4 (DR=direct repeat), TRE-pal (pal=palindrome) or TRE-lap (lap=inverted palindrome) in CV1 cells treated with 10 nM T(3). Of the mTRs examined, F451X (with a carboxy-terminal 11-amino-acid truncation) identified in a patient with RTH exhibited the strongest DNE on all TREs. The binding affinities between mTRs and corepressors SMRT or NCoR were quantified using a two-hybrid interference assay system consisting of VP16-TR(LBD) (LBD=ligand binding domain) and Gal4(DBD)-SMRT (DBD=DNA binding domain), or Gal4(DBD)-NCoR respectively, together with the Gal4 reporter gene. In this assay, VP16-TR(LBD) and Gal4(DBD)-SMRT (or Gal4 (DBD)-NCoR) interact with each other and trans-activate the Gal4 reporter gene. When an equal amount of mTR is coexpressed, it reduces the transcriptional activity of the reporter gene, depending on its binding avidity for a corepressor. A very strong correlation was observed between the SMRT-binding activity and the potency of the DNE among six natural mTRs and also among all mTRs, including four artificially constructed ones. The relationship between NCoR and DNE, however, was not significant. When we assayed the binding avidity of mTRs for RXR by using a two-hybrid assay system consisting of Gal4(DBD)-RXR(LBD) and VP16-TR(LBD), a significant correlation between DNE and binding avidity for the RXR was also observed. These results suggest that a corepressor plays an important role in DNE pathogenesis.

Analysis of Variance↗

Relationship between breast milk feeding and atopic dermatitis in children.

OBJECTIVE: To determine whether or not the breast milk feeding has a role in the prevalence of atopic dermatitis among children. METHODS: The target population of the study was all children participating in health check-up program for 3-year-old children in 60 municipalities locating 10 selected prefectures during designated 2 months between October and December 1997. Using a questionnaire, information on nutrition in infants (breast milk only, bottled milk only, or mixed), parity, mothers' age at birth, and a history of atopic dermatitis was obtained. Besides, data on potential confounding factors were obtained. RESULTS: Questionnaires from 3856 children (81.6% of those who were to participate in the programs, and 96.4% of children who participated them) were analyzed. After the adjustment for all potential confounding factors using unconditional logistic models, the risk of atopic dermatitis was slightly higher among children with breast milk (odds ratio [OR] = 1.16 with 95% confidence interval [CI] 0.96-1.40). Mothers' age at birth (OR for those who were more than 30 years or older in comparison with those who were younger than 30 years = 1.15; 95% CI, 0.96-1.37) and those with second or later parity orders (OR = 1.14, 95% CI; 0.95-1.35) showed odds ratios that were higher than unity without statistical significance. CONCLUSION: Breast milk elevates the risk of atopic dermatitis slightly without statistical significance; the risk may be, however, higher in children in second or later parity orders.

Adult↗

Giant cavernous hemangioma of the liver: is tumor size a risk factor for hepatectomy?

The aim of this study was to evaluate whether hepatic giant cavernous hemangioma (GCH) tumor size is a risk factor for hepatectomy. Twenty patients with GCH of the liver were treated by hepatic resection. Eleven patients with maximum resected specimen tumor size of >10 cm (mean tumor size, 18.5 cm; group 1) were compared with the 9 patients with tumor size. <10 cm (mean tumor size, 8.6 cm; group 2). The incidence of major hepatectomy in group 1 was significantly higher than that in group 2 (P = 0.0241). Although there were no significant differences in preoperative liver function, or in fibrinogen or platelet counts between the two groups, the level of preoperative fibrin degradation product (FDP) in group 1 was significantly higher than that in group 2 (P = 0.0116). Mean intraoperative hemorrhage volume, blood transfusion volume, and operation time in group 1 vs group 2 were 7003 ml vs 1092 ml (P = 0. 0251), 2927 ml vs 556 ml (P = 0.0169), and 431 min vs 216 min (P < 0. 0001), respectively. The incidence of postoperative complications in group 1 (45.5%) was higher than that in group 2 (22.2%), although not significantly so. There was no operative mortality in either group. Tumor size significantly correlated with intraoperative blood loss, operation time, weight of resected liver, intraoperative blood transfusion volume, and preoperative FDP levels. GCH tumor size is a significant risk factor for hepatectomy mainly because of the massive intraoperative blood loss and blood transfusion associated with major hepatic resection. More careful preoperative management to decrease tumor size may increase the safety of surgery for GCH of the liver.

Adult↗

Reresection for local recurrence of rectal cancer.

Local recurrence is one of the major reasons that rectal cancer surgery is unsuccessful. The aim of this study was to investigate the surgical characteristics of patients undergoing reresection for local recurrence of rectal cancer. A total of nine patients were enrolled in this study, six of whom underwent total pelvic exenteration, one, posterior exenteration, one, abdominoperineal resection with sacral resection, and one, lymph node dissection alone. The mean operative time was 8 h 15 min, and the mean operative blood loss was 2 325 ml. Although major postoperative complications occurred in four patients (44%), there were no postoperative or hospital deaths. Lateral lymph node metastasis was detected in all four patients whose lateral lymph nodes were dissected or extirpated at the reresection. Two patients survived for more than 5 years without rerecurrence, and the cumulative 5-year survival rate was 26%. The para-aortic lymph nodes were the most common site of first rerecurrence. The results of this study indicate that patients who undergo reresection for local recurrence of rectal cancer are at high risk of devel-oping lateral or para-aortic nodal metastasis. Nevertheless, reresection may be a therapeutic option for the local recurrence of rectal cancer.

Adenocarcinoma↗

Hepatic resection of giant cavernous hemangioma of the liver.

Surgical treatment of giant hemangioma of the liver is still controversial. The aim of this study is to examine the efficacy of hepatic resection for giant hemangioma of the liver. Twenty patients with giant cavernous hemangioma of the liver were treated by hepatic resection. The mean diameter of the hemangiomas was 13.9 cm (range, 6.5-30 cm). The surgical outcome was reviewed retrospectively. Major hepatectomy was performed in 14 patients and minor hepatectomy in 6 patients. Complications occurred in 7 of the 20 patients treated by hepatic resection. At a mean follow-up of 79 months (range, 12-173 months), 18 patients were symptom free whereas 2 patients had died--one died of pneumonia at 2 years and the other died of gastric cancer 6 years after surgery. Mean intraoperative hemorrhage and blood transfusion in all patients was 4,343 mL (range, 270-24,000 mL) and 1,860 mL (range, 0-8,800 mL) respectively. In the seven patients with preoperative high levels of fibrin degradation products (FDP), mean intraoperative hemorrhage and blood transfusion were markedly higher (9,371 mL and 3,714 mL respectively) than in the 13 patients without abnormal FDP (1,603 mL and 900 mL respectively). Preoperative hematologic status returned to normal after operation in all patients. Hepatic resection is a useful treatment for giant cavernous hemangioma of the liver. More careful management to reduce intraoperative hemorrhage is recommended to increase the safety of surgery, particularly in patients with preoperative abnormal FDP.

Adult↗