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M Koga

Publications and source records attributed to M Koga.

At least 235 records · Page 13Linked to original sources
PubMed1997

[Late phase reaction in atopic dermatitis--immunological parameters and immunohistological analysis].

We studied the correlation between late phase reaction (LPR) and laboratory data in atopic dermatitis (AD) and evaluated the pathological findings in LPR. We studied the correlation between LPR and the severity of AD, total IgE, specific IgE, total IgG4, specific IgG4 and eosinophils. There were correlations between immediate reaction (IR) and some laboratory data, but not between LPR and laboratory data. Pathological findings at 15 min 24 hrs and 48 hrs after dermal injection showed edema at 15 min, followed by epidermal eczematous changes in almost all cases at 24 hrs, edema and degeneration of dermal endothelial cells and surrounding connective tissue, and leukocytoclasia in half of the cases and deposition of C3 and IgG in parts. We found CD4+ cells in all layers of dermis, a greater ratio of EG2+ cells in deeper layers of dermis as time passed, and decrease of CD23+ cells after 24 hrs throughout the dermis. These changes were found in cases of IR-LPR+, too. It appears that the mechanism of LPR is complex and that IR is not indispensable, for LPR and that infiltration of CD4+ and EG2+ cells throughout all layers of dermis are important, and these condition were related to subsequent reactions.

Adolescent↗
PubMed1997

[Measurement of cerebral blood flow using phase-contrast MRI].

The development of phase-contrast magnetic resonance imaging(P-C MRI) provides a noninvasive method for measurement of volumetric blood flow(VFR). The VFR of the left and right internal carotid arteries and basilar artery were measured using P-C MRI, and total cerebral blood flow(tCBF) was calculated by summing up the VFR values in three vessels. We investigated the changes in these blood flows as influenced from age, head size, height, weight, body surface area and handedness. Moreover, regional CBF(rCBF) was measured by combining with the single photon emission computed tomography(SPECT) of 123I. The blood flows were 142 +/- 58 mL/ min(mean +/- SD) in the basilar artery, 229 +/- 86 mL/min in the left, 223 +/- 58 mL/min in the right internal carotid artery, and tCBF was 617 +/- 128 mL/min(Ref. Magn Resn Imaging 14:P. 1143, 1996). Significant increases were observed in head-size-related change of VFR in the basilar artery and height-related change of tCBF. The value of rCBF was easily acquired in combination with SPECT. Phase-contrast MRI is useful for a noninvasive and rapid analysis of cerebral VFR and has potential for clinical use.

Adolescent↗
PubMed1997

[Metabolic imaging of human brain tumors: H-1 chemical shift imaging and PET].

Positron Emission Tomography(PET) and Proton Chemical Shift Imaging(1H-CSI) has provided a cerebral metabolism. The glucose analog fluorine-18 fluorodeoxy-glucose(FDG) and amino acid analog 11C-L-methionine is the most commonly used PET tumor tracer. This time we compare with 1H-CSI and PET in gliomas and metastatic brain tumor with computer-assisted fusion images. We experienced some cases of the brain tumor. One case is metastatic brain tumor after radiation therapy, localized in right parietal hemisphere, with hemorrhage, and slightly accumulated Gd-DTPA in tumors. 11C-methionine PET demonstrates defects in tumors, but slight accumulated surrounding tumors. Accumulation of PET lesion is not elevated choline in CSI, but lactate is accumulated in tumors. Choline signal elevation seen in brain neoprasms, associated with increased cellular proliferation. Accumulation of PET and another accumulation of lactate in tumor are not demonstrate recurrence. Fusion image of PET and CSI is useful in understanding metabolism of brain tumor.

Aspartic Acid↗
PubMed1997

[Relationship between cholinergic symptoms caused by distigmine and the activities of serum AChE and BChE].

Distigmine is widely used for the treatment of dysuria, which is caused by various types of psychotropic medications. Distigmine, however, is also known to induce adverse cholinergic effects, such as diarrhea and salivation, with a decreased level of serum cholinesterase. We evaluated the possibility of using serum acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) as specific clinical markers for the adverse cholinergic effects of distigmine. Of the twelve patients treated with distigmine for dysuria caused by psychotropic drugs six patients presented both adverse cholinergic effects and decreased levels of serum AChE and BChE. The other six presented neither of these changes. This study suggests that the values of serum AChE and BChE may be useful markers for the manifestation of adverse cholinergic effects caused by distigmine.

Acetylcholinesterase↗
PubMed1997

[Association of IgA anti-GM1 antibody with antecedent diarrhea in patients with Guillain-Barré syndrome].

IgA has an important role in the gastrointestinal immune system. We investigated IgA anti-GM1 antibodies in Guillain-Barré syndrome (GBS) subsequent to diarrhea. IgA anti-GM1 antibodies were detected more often in GBS patients with a history of antecedent diarrhea than in those without that. Between the GBS patients with a history of prior symptoms of upper respiratory tract infections and those without that, we found no difference of the frequency of increased IgA anti-GM1 antibody titers. Six GBS patients who had antecedent symptoms of upper respiratory tract infections had IgA anti-GM1 antibodies. However, 5 patients of them also had a history of antecedent diarrhea. Our findings show that IgA anti-GM1 antibodies are associated with GBS following diarrhea.

Autoantibodies↗
PubMed1997

[No association between IgG anti-GTla antibody and bulbar palsy in Guillain-Barré and Fisher's syndromes].

Pharyngeal-cervical-brachial weakness (PCB) is a rare variant of Guillain-Barré syndrome (GBS) and shows a regional muscle weakness, specially in oropharynx. Mizoguchi et al. (1994) reported a GBS patient with PCB-like symptoms who had serum IgG anti-GTla antibodies in the acute phase of illness. We therefore assumed that bulbar palsy was associated with anti-GTla antibodies and made serological study in patients with GBS or Fisher's syndrome. The frequency of positive IgG anti-GTla antibody was significantly higher in patients with bulbar palsy than those without bulbar palsy. Most of the patients with IgG anti-GTla antibodies, however, had also anti-GQlb antibodies in their sera and anti-GTla antibodies were more closely associated with ophthalmoplegia than with bulbar palsy. These findings do not support that IgG anti-GTla antibodies play an important role in the pathogenesis of bulbar palsy in GBS.

Autoantibodies↗
PubMed1997

Circadian changes in body temperature during the menstrual cycle of healthy adult females and patients suffering from premenstrual syndrome.

The biological rhythm of females is closely related to the menstrual cycle, and this rhythm is believed to influence circadian changes in body temperature. This study investigated and compared the patterns of circadian changes in the body temperature of healthy adult females and patients suffering from premenstrual syndrome or major depression. Body temperature was measured both rectally and sublingually in healthy subjects, and only sublingually in the patients. During the luteal phase in healthy adult females, both the average and lowest nocturnal body temperatures increased, the amplitude of the circadian changes decreased, and the times of the lowest and highest temperatures within a 24-hour period were delayed by 2-3 h. In the patients, the amplitude decreased during disease periods, especially in the follicular phase, whereas in the luteal phase, circadian changes showed great variation each day, although the decrease in amplitude was not as remarkable. The results show that (i) the biological rhythm of females is intrinsically unstable in the luteal phase, although this rhythm is stable in the follicular phase; and, (ii) symptoms were often aggravated with the decreases in amplitude experienced in the luteal phase.

Adult↗
PubMed1996

Genomic structure and 5' regulatory regions of the let-23 gene in the nematode C. elegans.

The let-23 gene in the nematode Caenorhabditis elegans encodes a receptor tyrosine kinase and is necessary for the induction of a vulva, survival past the L1 stage, hermaphrodite fertility and for male spicule development. We sequenced the entire let-23 genomic region of over 12 kb. The 5' end of the let-23 mRNA was mapped by sequencing polymerase chain reaction products, and two mRNAs were found which had alternative exons and were probably initiated at different sites. One transcript was trans-spliced to SL1. Expression of either cDNA rescued a let-23 vulvaless mutation in germline transformation. These results suggest that the let-23 gene encodes two proteins of 1323 or 1335 amino acid residues. We prepared various 5' deletion constructs of the let-23 gene, and examined their rescue activities for a let-23 lethal or vulvaless mutation. The results revealed that two regions were required for let-23 expression, one for larval survival and the other for vulva formation. We also cloned and analyzed a let-23 homologue from Caenorhabditis vulgaris. It can encode two proteins of 77% amino acid residue identity with the Let-23 proteins. The 12 kb fragment carrying the C. vulgaris gene rescued the let-23 vulvaless mutation in C. elegans. Seventeen sequences highly conserved between the two species were identified in the 5' upstream region or within an intron. Three of these sequences are contained in the two regions required for let-23 expression, suggesting that they are cis-acting elements for let-23 expression.

Amino Acid Sequence↗
PubMed1996

Habitual and genetic factors that affect urinary background levels of biomarkers for organic solvent exposure.

Urinary hippuric acid, phenol, and o-cresol, which are biomarkers for toluene, benzene, and phenol exposures, are usually present in a significant amount in urine collected from subjects who have not been occupationally exposed to the organic solvents. With the improvement of working environments, the urinary concentrations of the biomarkers have become lower and closer to the levels of urine from unexposed subjects. It is very useful to clarify the background levels of these biomarkers and the factors which effect the background levels of the biomarkers in order to make effective use of biological monitoring under low level exposure. In the present study, the effects of life habits and the genetic polymorphisms of the metabolizing enzymes on the background levels of urinary hippuric acid, phenol and o- and p-cresol were clarified, using 351 males (means age: 38.6, range: 19-71) who were not occupationally exposed to hazardous chemical materials. Their life habits, smoking, alcohol consumption, and dietary habits were examined by means of a questionnaire. The genotypes of five metabolizing enzymes, that is, low Km aldehyde dehydrogenase (ALDH2), polymorphic N-acetyl transferase (NAT2), cytochrome P-4501A1 (CYP1A1), cytochrome P-4502E1 (CYP2E1), and glutathione-S-transferase mu (GSTM1) were determined form peripheral blood samples. The urinary hippuric acid and creatinine were analyzed by HPLC and urinary phenol, o-, p- and m-cresol were determined by GC/MS. Recoveries and the coefficients of variance of phenol, o-cresol, and p-cresol ranged from 92.7 to 107.8% and 1.3% to 6.7%, respectively. Linear relationships between the concentrations of phenol, o- and p-cresol, and their peak area ratios were observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetyltransferases↗
PubMed1996

Effect of triiodothyronine on graft function in a model of heart transplantation.

BACKGROUND: Brain death is associated with neuroendocrine changes that result in impaired metabolism, reduced myocardial energy stores, and deteriorating cardiac function. As a result of these changes, a substantial number of normal human hearts are not considered suitable for transplantation. In the hope of preventing these complications and stabilizing the condition of cardiac donors, we compared the function of transplanted hearts from brain-dead rats that received triiodothyronine (T3) (n = 6) with that of hearts from a group that received a placebo (n = 5). METHODS: This experiment was designed to be both blinded and randomized. Brain death was achieved by bilateral carotid ligation and inflation of an intracranial balloon. Triiodothyronine or placebo was administered in a blinded, randomized fashion. The brain-dead donors were then supported with conventional techniques for 2 hours after which time heterotopic transplantation was performed using hypothermic preservation and a working heart model. Hemodynamics of the transplanted hearts were assessed 48 hours postoperatively. RESULTS: The hearts from donors that had been pretreated with T3 were found to have a significantly higher (p < 0.005) peak left ventricular pressure than the hearts from the placebo-treated group (137 +/- 17 mm Hg versus 115 +/- 15 mm Hg). Left ventricular end-diastolic pressure was significantly lower (p < 0.01) in the T3-treated group (5.2 +/- 2.2 mm Hg) compared with the placebo-treated group (6.9 +/- 0.5 mm Hg). There was also a significantly higher (p = 0.03) maximal first derivative of left ventricular pressure in the T3-treated group compared with the placebo-treated group (4,876 +/- 1,348 mm Hg/s versus 3,344 +/- 1,016 mm Hg/s). Finally, the cardiac output in the group given T3 was 93 +/- 16 mL/min compared with 61 +/- 22 mL/min in the group given the placebo (p < 0.01). CONCLUSIONS: Hearts from brain-dead rats that had received T3 before transplantation showed improved postoperative function. The experimental design of predonation brain death, cold immersion storage, and transplantation in a working heart model should make these data more relevant clinically than those previously reported.

Abdomen↗
PubMed1996

Noninvasive analysis of water movement in rat testis using deuterium magnetic resonance imaging.

To measure water movement in the testis without the effects from the blood-testis barrier, we performed in vivo deuterium magnetic resonance imaging (2H MRI) of rats administered with deuterated saline. Alcohol was injected into one testis of each animal and the other was administered with normal saline as a control. Dynamic 2H MRI was obtained at 2 T by FLASH pulse sequence (TR, 300 ms; TE, 10 ms; alpha = 90 degrees) using a surface coil (3 cm in diameter). The variation in 2H signal intensity between the two testes as a function of time after deuterated saline injection was examined every 1.1 min up to 20 min. The signal intensity in the testis receiving the alcohol treatment was lower than that in the normal control. Thus, deuterium MRI can be used to analyze functional disorders of the testis.

Animals↗
PubMed1996

Prevalence of hepatitis B or C virus infection in patients with fulminant viral hepatitis. An analysis using polymerase chain reaction.

BACKGROUND/METHODS: The cause of fulminant hepatitis is still not fully understood. We studied 23 patients with fulminant hepatitis, using polymerase chain reaction to detect hepatitis virus genomes. Tests for HBsAg and IgM anti-HAV and IgM anti-HBc were performed in all patients. Serum samples were stored at -70 degrees C for later analysis of anti-HCV and hepatitis virus genomes such as hepatitis B virus, hepatitis C virus and hepatitis D virus. RESULTS: Of 23 patients, 17 (74%) had HBV-DNA and two (9%) had HCV-RNA. No patient was positive for both viruses or positive for HDV-RNA. Serological tests indicated that two patients, negative for HBV-DNA and HCV-RNA, were positive for IgM anti-HAV. In contrast, 8 of 17 (47%) HBV-DNA positive patients were negative for both IgM anti-HBc and HBsAg in conjunction with low levels of viremia. Four patients were positive for anti-HCV, but only one was positive for HCV-RNA. One patient, positive for HCV-RNA, was negative for anti-HCV. CONCLUSIONS: Our results indicate that analysis of hepatitis virus genomes using polymerase chain reaction allows accurate identification of the virus causing fulminant hepatitis.

Adolescent↗
PubMed1996

Three-vessel study of cerebral blood flow using phase-contrast magnetic resonance imaging: effect of physical characteristics.

The development of phase-contrast magnetic resonance imaging (P-C MRI) provides a noninvasive method for measurement of volumetric blood flow (VFR). We performed P-C MRI to study the effects of physical characteristics on cerebral blood flow. VFR of the left and right internal carotid arteries and basilar artery were measured using P-C MRI and total cerebral blood flow (tCBF) was calculated by summing up the VFR values in the three vessels. Moreover, we investigated the changes in these blood flows as influenced by age, head size, height, weight, body surface area, and handedness. The blood flows were 142 +/- 58 ml/min (mean +/- standard deviation) in the basilar artery; and 229 +/- 86 ml/min in the left, and 223 +/- 58 ml/min in the right internal carotid artery; and tCBF was 617 +/- 128 ml/min. Significant increases were observed in head size-related change of VFR in the basilar artery (p = .028) and height-related change of tCBF (p = .045). The other characteristics did not significantly influence any VFR. The results suggest that head size and height may reflect CBF, and that these effects should be considered when changes of CBF are diagnosed. Phase-contrast MRI is useful for a noninvasive and rapid analysis of cerebral VFR and has potential for clinical use.

Adolescent↗
PubMed1996

Localization and clinical significance of thyrotropin receptor mRNA expression in orbital fat and eye muscle tissues from patients with thyroid-associated ophthalmopathy.

We have studied the cellular localization of thyrotropin receptor (TSH-R) mRNA in orbital fat and extraocular muscle tissues from patients with thyroid-associated ophthalmopathy (TAO) using Northern blot, reverse transcriptase polymerase chain reaction (RT-PCR), and in situ hybridization, and we correlated the findings with clinical estimates of ophthalmopathy. Although we failed to detect TSH-R mRNA in orbital tissues by Northern blot, TSH-R cDNA was amplified in orbital fat tissue from 13 of 25 patients with TAO and from 2 of 4 control subjects, in eye muscle tissue from 2 out of 7 patients with TAO, and in cultured orbital fibroblasts and subcutaneous fibroblasts from TAO patients. In situ hybridization showed that TSH-R mRNA was detected in cultured orbital fibroblasts as well as skin fibroblasts obtained from the patient. Furthermore, the expression of TSH-R mRNA in orbital fat tissue from patients with TAO significantly correlated with the orbital fat volume and the severity of ophthalmopathy, especially the extent of eye muscle dysfunction. These results suggest that the expression of TSH-R in the orbit, especially fibroblasts, may play a role in the pathogenesis and clinical manifestations of the ophthalmopathy in patients with TAO, although a secondary effect, involving fibroblasts in TAO is also possible.

Adipose Tissue↗
PubMed1996

Clinical manifestations of HBsAg and anti-HCV negative chronic liver disease in Nagasaki Prefecture, Japan.

The discovery of hepatitis C virus (HCV) has enabled the diagnosis of type C chronic liver disease, which had in the past been diagnosed as part of non-A, non-B chronic liver disease. Although most cases with chronic liver disease are caused by hepatitis B virus (HBV) or HCV infection, there are still cases of non-B, non-C chronic liver disease. Forty patients with chronic liver disease, who were seronegative for hepatitis B surface antigen and antibody to HCV, were followed for a mean period of 72 months. The clinical manifestations in these patients were compared with those reported for type B and type C chronic liver disease. Of the 40 patients, 22 were diagnosed with chronic hepatitis, 14 with liver cirrhosis and 4 with hepatocellular carcinoma (HCC). Twenty-seven (67.5%) patients showed mild alanine aminotransferase activity profiles, and the natural clinical course of most patients showed a slow progression compared with that reported for type B and type C patients. The yearly incidence of HCC was 9.7% in patients with liver cirrhosis and 3.9% in chronic hepatitis. These rates were similar to those in type B or type C patients. This suggests that our population sample contained a number of patients with type B, type C or other etiologic agent(s), because 66.7% of the patients who developed HCC had some evidence of exposure to HBV or HCV. Our results suggest that more detailed and accurate tests for detecting HBV and HCV should be considered before making the diagnosis of non-B, non-C chronic liver disease, and that there is the need to reveal unknown etiologic agent(s).

Adolescent↗
PubMed1996

[Chest wall reconstruction after the resection of primary chest wall tumors].

Between April 1983 and June 1994, we performed chest wall reconstructions on 9 patients (7 males and 2 females) out of 27 all of whom underwent the radical resection for the primary chest wall tumors. Histological diagnosis of tumors included 6 chondrosarcomas, 1 Ewing's sarcoma, 1 plasmacytoma and 1 giant cell tumor. Six lesions were located on the rib and 3 on the sternum. For the materials for reconstruction of the chest wall use a polyethylene plate in 2 patients, a Marlex mesh in 5 patients and a Marlex mesh with a methyl methacrylate utilizing the sandwich method in 2 patients. The polyethylene plate proved to be satisfactory for maintaining stability of the chest wall. However, our experience using this plate showed intensive foreign body reactions, and discovering these we have not use the polyethylene plate. Marlex mesh had an affinity with human tissue and was very easy to use and produced no complications. We use Marlex mesh for flat surfaces on the anterior or posterior chest wall. Marlex mesh and methyl methacrylate utilizing the sandwich method, combined the solidity and shaping of methyl methacrylate with the benefit such as easy fixation and excellent incorporation of the mesh.

Adult↗