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Biomedical subjects

K Kuroda

Publications and source records attributed to K Kuroda.

At least 37 records · Page 2Linked to original sources

Etizolam-induced superficial erythema annulare centrifugum.

Erythema annulare centrifugum (EAC) is characterized by slowly enlarging annular erythematous lesions. Although the origin is not clear in most cases, EAC has been associated with infections, medications, and in rare cases, underlying malignancy. We describe a patient who developed annular erythematous lesions after etizolam administration. The eruptions were typical of the superficial form of EAC, both clinically and histopathologically. The lesions disappeared shortly after discontinuation of the medication. Patch testing with etizolam gave positive results. To our knowledge this is the first reported case of etizolam-induced superficial EAC.

Aged↗

Acute haemorrhagic oedema of infancy associated with cytomegalovirus infection.

Acute haemorrhagic oedema (AHO) of infancy is a cutaneous leukocytoclastic vasculitis, clinically characterized by the acute development of peripheral oedema and targetoid purpuric lesions on the face and extremities. It usually affects children younger than 2 years of age. The disorder follows a benign course usually without recurrence or long-term complication. In most cases the origin is not clear, but underlying infections are assumed to play an aetiological role. We describe a 7-month-old boy whose clinical and histopathological features are typical of AHO. Serological tests clearly demonstrated a primary infection for cytomegalovirus (CMV). To our knowledge, this is the first reported case of AHO associated with CMV infection.

Acute Disease↗

Clinical study on the antiseptic effect of povidone-iodine solution for the surgical field of digestive tract operations.

Our previous study showed 10% povidone-iodine solution (Isodine) to be safe and effective for skin antisepsis in healthy young adults. The present study was carried out in 45 adult and old-age patients undergoing surgery (average age 62 years). 10% povidone-iodine solution was effective for skin antisepsis; however, after completion of the intra-abdominal procedures, contaminations were found due to the type II and IV operations with unprotected incision sites and wound walls. Diabetes was found to be one of the most important factors in surgical site infection. In conclusion, the antiseptic efficacy immediately after application of 10% povidone-iodine solution was evidenced in surgical patients with class II wounds. The solution was also effective for the prevention of postoperative skin wound infection.

Adult↗

Cortical silent period in the tongue induced by transcranial magnetic stimulation.

Cortical silent period (SP) of the limb muscles is thought to reflect the cortical excitability. However, the lingual SP has not been examined precisely even in normal subjects. We investigated SP in the tongue induced by transcranial magnetic stimulation (TMS) in 18 controls. Surface electrodes were placed on the lingual dorsum using a bipolar technique. A round coil (13.5 cm in outer diameter) connected with Magstim 200 stimulator was placed on the motor cortex of the tongue, and the intensity of the stimulation was increased stepwise to maximum. SP was detected in all subjects especially at the contralateral side to the stimulated side, without contamination of peripheral SP. The duration of SP depended on the stimulus intensity, while the degrees of muscle contraction did not influence SP. SP of the tongue showed similar characteristics to that of limb muscles. This suggests that SP of lingual muscles can be clinically useful for the evaluation of corticobulbar excitability.

Adult↗

Effect of diazepam binding inhibitor (DBI) on the fluid intake, preference and the taste reactivity in mice.

We have reported that a diazepam binding inhibitor (DBI)-like peptide is released by the aversive quinine stimuli 'Chem. Senses 25 (2000) 739'. To determine the effect of DBI on the fluid intake, we injected a DBI peptide fragment into the fourth ventricle in mice. DBI suppressed the intake of 5% sucrose, water and 0.9 mM quinine-HCl and the preference for 0.05% saccharin. Administration (i.p.) of flumazenil, a benzodiazepine receptor antagonist, 20 min before the injection of DBI (i.c.v.) antagonized the suppressive effect of DBI on the intake and the preference for saccharin. We also studied the dose dependency of the effect of DBI on the intake of 5% sucrose. Injection of DBI in excess of 3 microg suppressed the intake of 5% sucrose in mice. Furthermore, injection of DBI (i.c.v.) increased the aversive response to 0.9% NaCl in the taste reactivity in mice. These results suggest that DBI affect the preference to food.

Animals↗

Preparation and HREM characterization of a protonated form of a layered perovskite tantalate from an Aurivillius phase Bi(2)SrTa(2)O(9) via acid treatment.

An Aurivillius phase, Bi(2)SrTa(2)O(9), which consists of perovskite-like slabs and bismuth oxide sheets, was treated with 3 M hydrochloric acid for 72 h, and the resultant product was characterized. Scanning electron microscopy investigation indicated that no morphological change occurred during the acid treatment. X-ray diffraction (XRD) analysis revealed that the product exhibited tetragonal symmetry with a = 0.391 +/- 0.004 nm and c = 0.98 +/- 0.01 nm, and the a parameter is consistent with a typical value for cubic perovskite oxides. High-resolution electron microscopy (HREM) observations along both [001] and [010] showed that the structure of the perovskite-like slabs in Bi(2)SrTa(2)O(9) was retained after the acid treatment. The compositional analyses revealed the loss of a large portion of bismuth and a part of strontium (present in the bismuth oxide sheets due to B <--> Sr disorder) and the introduction of protons. These observations indicate that the bismuth oxide sheets in Bi(2)SrTa(2)O(9) were selectively leached and that protons were introduced into the interlayer space to form a protonated layered perovskite, H(1.8)[Sr(0.8)Bi(0.2)Ta(2)O(7)]. Though diffraction techniques (XRD and electron diffraction) demonstrated that an average structure of H(1.8)[Sr(0.8)Bi(0.2)Ta(2)O(7)] consisted of perovskite-like slabs stacked without displacement, HREM observation along [010] demonstrated that both a simple stacking sequence without displacement (P-type) and a stacking sequence with a relative displacement by (a + b)/2 (I-type) were present in H(1.8)[Sr(0.8)Bi(0.2)Ta(2)O(7)].

Journal Article↗

Stable operation of a 300-m laser interferometer with sufficient sensitivity to detect gravitational-wave events within our galaxy.

TAMA300, an interferometric gravitational-wave detector with 300-m baseline length, has been developed and operated with sufficient sensitivity to detect gravitational-wave events within our galaxy and sufficient stability for observations; the interferometer was operated for over 10 hours stably and continuously. With a strain-equivalent noise level of h approximately 5x10(-21)/sqrt[Hz], a signal-to-noise ratio of 30 is expected for gravitational waves generated by a coalescence of 1.4M-1.4M binary neutron stars at 10 kpc distance. We evaluated the stability of the detector sensitivity with a 2-week data-taking run, collecting 160 hours of data to be analyzed in the search for gravitational waves.

Astronomy↗

Detection and typing of TT virus DNA genotype by the PCR-RFLP method.

TT virus (TTV) is a novel single-stranded DNA virus that was identified in patients with post-transfusion-hepatitis of non-A-G type in Japan in 1997. We developed a new detection and typing method for TTV DNA strains, by combining polymerase chain reaction (PCR) and restriction fragment length polymorphism (PCR-RFLP) techniques. TTV DNA was amplified by nested-PCR with TTV-specific mixed primers derived from the conserved open reading frame 1 (ORF1) region of the published TTV DNA sequences. Using the enzymes Hae III, Dra I, Eco RI and Pst I, we were able to distinguish between the four TTV genotypes. In 200 serum samples obtained from healthy pregnant women at an outpatient clinic, the positive rate of TTV detection was 27.0%, almost identical to the positive rate of the detection of ORF1-PCR in Japanese healthy individuals. The strains detected in the positive serum samples were genotype 1a (9.3%), genotype 1b (11.1%), genotype 2 (51.9%), genotype 3 (7.4%) and other genotypes (1.9%). This results indicate that genotype 1 and genotype 2 were the two major strains in the Japanese population. Moreover, 10 serum samples (18.5%) presented RFLP patterns in which some genotypes were mixed.

DNA Restriction Enzymes↗

Brain PET and technetium-99m-ECD SPECT imaging in Lhermitte-Duclos disease.

Two patients with Lhermitte-Duclos disease were evaluated by brain positron emission tomography (PET) and technetium-99m-ethyl cysteinate dimer (99mTc-ECD) single-photon emission computed tomography (SPECT). In the lesions in both patients, hyperperfusion was detected on cerebral blood flow images obtained by PET, and hyperactivity by standard 99mTc-ECD SPECT. Dynamic 99mTc-ECD SPECT images demonstrated a plateau of activity in each lesion. These findings suggest that lesions in Lhermitte-Duclos disease have a retention mechanism for 99mTc-ECD equivalent to that of normal neural tissue.

Adolescent↗

Cell surface-engineered yeast displaying a histidine oligopeptide (hexa-His) has enhanced adsorption of and tolerance to heavy metal ions.

A histidine oligopeptide (hexa-His) with the ability to chelate divalent heavy metal ions was displayed on the yeast cell surface for the purpose of enhanced adsorption of heavy metal ions. We genetically fused a hexa-His-encoding gene with the gene encoding the C-terminal half of alpha-agglutinin that includes a glycosylphosphatidylinositol anchor attachment signal sequence and attached the hexa-His peptide on the cell wall of Saccharomyces cerevisiae. This surface-engineered yeast adsorbed three to eight times more copper ions than the parent strain and was more resistant to copper (4 mM) than the parent (below 1 mM at pH 7.8). It was possible to recover about a half of the copper ions adsorbed by whole cells with EDTA treatment without disintegrating the cells. Thus, we succeeded in constructing a novel yeast cell with both tolerance to toxic contaminants and enhanced adsorption of metal ions onto the cell surface.

Adsorption↗

Combination of early and delayed SPET imaging using technetium-99m ethyl cysteinate dimer immediately after local intra-arterial thrombolysis.

The aim of this study was to investigate the prognostic utility of post-treatment technetium-99m ethyl cysteinate dimer (99mTc-ECD) single-photon emission tomography (SPET) for predicting ischemic tissue outcome in cases involving embolic middle cerebral artery occlusion treated with local intra-arterial thrombolysis. We examined twenty-five patients with a moderately ischemic area determined using pretreatment technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) SPET, and with complete recanalization within 6 h. Post-treatment 99mTc-ECD SPET studies, consisting of scanning for 0.5-6.5 min (early scan) and 15-21 min (delayed scan) after tracer injection, were performed immediately after thrombolysis. The extent of the affected area outlined on pretreatment 99mTc-HMPAO SPET was used for the post-treatment early and delayed 99mTc-ECD SPET images, and the AR/CE ratio (ratio of affected regional activity to cerebellar activity) was calculated. The washout index of 99mTc-ECD in the affected area was also calculated by dividing the difference between the AR/CE ratio in the early and delayed images by the AR/CE ratio in the early image. Twelve patients without infarction or with small subcortical/basal ganglial infarction, ten with medium or large cortical infarction, and three with hemorrhage were identified by follow-up computed tomography. Although the AR/CE ratio in post-treatment early 99mTc-ECD SPET images was significantly higher in the hemorrhagic group than in the cortical infarction group, this value did not differentiate the reversible ischemia group from either the cortical infarction or the hemorrhagic group. The AR/CE ratio in post-treatment delayed 99mTc-ECD SPET images statistically differentiated the reversible ischemia group from both the cortical infarction and the hemorrhagic group. However, the difference between the cortical infarction and hemorrhagic groups was not statistically significant. The washout index of 99mTc-ECD statistically differentiated all three groups. This study demonstrated that a combination of early and delayed 99mTc-ECD SPET imaging performed immediately after thrombolysis predicts ischemic tissue outcome.

Adult↗

Up-regulation of putative hyaluronan synthase mRNA by basic fibroblast growth factor and insulin-like growth factor-1 in human skin fibroblasts.

Recently, cDNAs for the three putative human hyaluronan synthase (HAS) genes, HAS1, HAS2 and HAS3, have been cloned. In this study we investigated the effects of basic fibroblast growth factor (bFGF) and insulin-like growth factor-1 (IGF-1) on the expression of HAS genes in cultured skin fibroblasts. Northern blot analyses showed that treatment of fibroblasts with bFGF enhanced the mRNA levels of all three genes. HAS2 gene expression showed the strongest up-regulation with a more than 10-fold increase at 50 ng/ml of bFGF. bFGF also increased hyaluronan production. Incubation of fibroblasts with IGF-1 increased HAS1, HAS2, and HAS3 mRNA levels, as well as hyaluronan production. Our results suggest that up-regulation of the HAS genes by bFGF and IGF-1 is closely associated with the stimulation of hyaluronan synthesis, and that effects of growth factors on HAS gene expression may have important implications for tissue remodeling, such as in development and wound healing.

Base Sequence↗

Glut1 expression in T1 and T2 stage colorectal carcinomas: its relationship to clinicopathological features.

Glucose uptake is mediated by glucose transporter (Glut) proteins, which exhibit altered expression in a variety of malignant neoplasms. Glut1 expression is thought to be a potential marker for malignant transformation. The aim of the present study was to investigate the expression of Glut1 protein in colorectal adenomas, T1 and T2 stage carcinomas. Immunohistochemical detection of Glut1 protein was examined in 141 formalin-fixed and paraffin-embedded colorectal tumour specimens (57 adenomas, 84 carcinomas). The degree of Glut1 immunostaining of a specimen was graded according to the proportion of Glut1-positive cells in it; absent (positive cells are 0%), weakly positive (less than 10%), moderately positive (10-50%), and strongly positive (more than 50%). Glut1 expression was present in 18% of the adenomas with low-grade dysplasia, and in 63% of the adenomas with high-grade dysplasia. The positivity in such lesions was usually weak, but was moderate in 8% of the adenomas with high grade dysplasia. For the carcinomas, there were significant correlations between Glut1-positivity and depth of invasion (T1 45% versus T2 74%, P<0.01), histological differentiation (well 49% versus moderately to poorly 74%, P< 0.05) and morphological type (polypoid 42% versus depressed 73%, P< 0.05), if the cut-off value was set at 10% of cells. In conclusion, we clarified the relationship between Glut1 expression and clinicopathological features in T1 and T2 stage colorectal carcinomas, and our results suggested a high malignant potential of the depressed-type carcinoma.

Adenocarcinoma↗

Enhancement of the thermophilic stage in cattle waste composting by addition of tofu residue.

The microbial degradation and temperature rise during the composting of a cattle waste and rice straw mixture blended with tofu (soybean curd) residue was investigated using an insulated and unheated in-vessel composter (effective volume, 12 1) and a static pile with passive aeration. The addition of 11% (dry weight basis) of tofu residue shortened the time required for temperature to reach the thermophilic phase and increased the duration of the temperatures above 55 degrees C significantly, but the maximum temperature was not affected by the additive level. As shown by the change in BOD, most of the easily biodegradable matter in the tofu residue was consumed during 12 days of composting. The same results were observed in the temperature profile of the static pile with passive aeration. Tofu residue addition yielded a higher maximum temperature and a nearly two times longer duration of temperatures above 55 degrees C in almost all locations of the pile. The use of tofu residue as a co-composting material would promote thermophilic degradation throughout the entire composting mass.

Animals↗

Characterization of sago palm (Metroxylon sagu) lignin by analytical pyrolysis.

Dioxane lignin prepared from sago palm (Metroxylon sagu) was characterized by analytical pyrolysis coupled to gas chromatography-mass spectrometry. Large abundances of the p-hydroxybenzoates ester-linked to the lignin were proven by analytical pyrolysis as well as by mild alkaline treatment that produced p-hydroxybenzoic acid in 16.3% yield. Pyrolysis in the presence of tetramethylammonium hydroxide (TMAH) before and after alkaline treatment also showed the presence of ester- and ether-linked p-hydroxybenzoates. Quantitative results of pyrolysis showed that the sago palm lignin is of syringyl type. The relative abundances of TMAH/pyrolysis products derived from the syringyl beta-aryl ether substructures were 4.9 times those of the guaiacyl equivalents. Proton nuclear magnetic resonance analysis also showed the presence of the p-hydroxybenzoates and the predominance of the syringyl moiety over the guaiacyl ones in the sago palm lignin.

Gas Chromatography-Mass Spectrometry↗

Altered expression of angiopoietins and Tie2 endothelium receptor in psoriasis.

Psoriasis is a chronic inflammatory skin disease in which epidermal proliferation is closely associated with excessive microvascular expansion within the papillary dermis. Angiopoietins have recently been identified as the major ligands of the endothelial- specific receptor Tie2. Angiopoietin 1 induces Tie2 signaling as a receptor activator and maintains blood vessel formation, whereas angiopoietin 2 destabilizes vessels by blocking Tie2 signaling as an antagonist of angiopoietin 1 and acts with vascular endothelial growth factor to initiate angiogenesis. In this study we examined the potential role of angiopoietins and the Tie2 receptor in vascular changes of psoriasis. Angiopoietin 1, angiopoietin 2, and Tie2 were upregulated in involved psoriasis skin compared to uninvolved psoriasis skin, healthy skin, and chronic spongiotic dermatitis skin. Angiopoietin 1 was expressed by stromal cells in the highly vascularized papillary dermis of involved psoriasis skin. Angiopoietin 2 was expressed by endothelial cells in the vicinity of the proliferating epidermis that abundantly expressed vascular endothelial growth factor. Vascular endothelial growth factor and basic fibroblast growth factor, which were overexpressed in involved psoriasis skin, enhanced angiopoietin 2 and Tie2 expression in dermal microvascular endothelial cell cultures. Thus, our findings suggest that upregulation of angiopoietin 1, angiopoietin 2, and Tie2 is closely associated with the development of microvascular proliferation in psoriasis, and that the angiopoietin-Tie2 system may act coordinately with vascular endothelial growth factor and basic fibroblast growth factor to promote neovascularization in psoriasis. Moreover, successful antipsoriatic treatment was accompanied by noticeable reduction of angiopoietin 2 expression, suggesting that alteration of angiopoietin 2 expression may be particularly important in controlling vascular proliferation in the treatment of psoriasis.

Angiopoietin-1↗

Dynamic and static 99mTc-ECD SPECT imaging of subacute cerebral infarction: comparison with 133Xe SPECT.

UNLABELLED: 99mTc-ethylcysteinate dimer (99mTc-ECD) SPECT imaging reportedly fails to show reflow hyperemia in patients with subacute stroke. This study attempts to determine the clinical usefulness of dynamic 99mTc-ECD SPECT in evaluating regional blood flow in subacute cerebral infarction and the kinetic behavior of 99mTc-ECD in infarct areas. METHODS: 133Xe and consecutive dynamic and static 99mTc-ECD SPECT studies were performed on 24 patients with cortical infarction in the middle cerebral artery territory 13-15 d after the onset of a stroke. Image contrast between infarct and contralateral control areas on 99mTc-ECD tomograms (ECD uptake ratio) was compared with that on cerebral blood flow (CBF) images obtained using 133Xe inhalation (CBF ratio). RESULTS: In all cases, ECD uptake ratios from static images were lower than CBF ratios. This tendency was obvious when CBF in the infarct area increased above the normal control value, and no significant correlation was found between ECD uptake ratios from static images and CBF ratios. Only in the infarct areas with CBF below the normal control value, however, was a significant correlation between the two maintained (r = 0.795; P = 0.0011). A very strong correlation was found between CBF ratios and ECD uptake ratios on both the first dynamic scan (36 s after injection) (r = 0.991; P < 0.0001) and the second dynamic scan (72 s after injection) (r = 0.945; P < 0.0001). The correlation coefficient decreased in a time-dependent manner, with no significant correlation observed after the fourth dynamic scan (144 s after injection). On the other hand, significant correlations were observed on all dynamic scans only in the infarct areas with CBF below the control value. CONCLUSION: Super-early images of dynamic 99mTc-ECD SPECT provide a close imaging contrast with CBF and reveal reflow hyperemia in areas with irreversible changes produced by subacute stroke, which static 99mTc-ECD SPECT images fail to show. Decreased retention of the tracer in the infarct areas with hyperperfusion causes an underestimation of CBF on static 99mTc-ECD SPECT images. Given these results, we believe that dynamic 99mTc-ECD SPECT is an effective clinical tool to evaluate regional blood flow in subacute cerebral infarction.

Adult↗