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Biomedical subjects

M Koga

Publications and source records attributed to M Koga.

At least 109 records · Page 6Linked to original sources
PubMed2000

Proposed abdominal sonographic staging to predict severity of liver diseases: analysis with peritoneoscopy and histology.

Abdominal sonography is a routinely used noninvasive modality for screening and treatment of liver diseases. We attempted to establish a morphological sonographic staging to predict the severity of liver diseases with their consequent analysis with morphological staging of peritoneoscopy and histology. In all, 136 patients were enrolled for the final confirmation of disease state by peritoneoscopy and histology preceded by abdominal sonography. All patients were categorized from stage 0 to stage 5, depending on a proposed criterion of sonographic features based on surface pattern of liver and the appearance of internal echogenic bands relating to the irregularity of the liver texture. A digitized computer quantitation of histogram-based standard deviation (SD) values from different stages of sonographic images was analyzed, and their values were justified by correlation with the definite appearance of an internal echogenic band. The association of different sonographic stages with disease progression was also demonstrated by their relation with peritoneoscopy and histology. In all patients, the different sonographic staging results were significantly correlated with hepatic surface features of peritoneoscopic staging (r = 0.939, P < 0.0001) graded from stage 0 to stage 5 and were also correlated with biopsy-proven staging of fibrosis (r = 0.739, P < 0.0001). The greater SD values of histogram-based echo levels, as analyzed from digitized sonographic images of 90 patients, were associated with the appearance of internal echogenic bands (P < 0.0001). Furthermore, the corresponding SDS were significantly correlated with the qualitative staging of sonographic features (r = 0.781, P < 0.0001), peritoneoscopy (r = 0.786, P < 0.0001) and histology (r = 0.779, P < 0.0001). We concluded that our proposed sonographic staging is well correlated with peritoneoscopic and histological staging of liver diseases, with only a small discrepancy, and can be used clinically to demonstrate the ongoing severity of liver diseases.

Abdomen↗
PubMed2000

Is Campylobacter lipopolysaccharide bearing a GD3 epitope essential for the pathogenesis of Guillain-Barré syndrome?

The hypothesis has been proposed that the GD3 ganglioside-like lipopolysaccharide (LPS) is essential for and functions in the development of Guillain-Barré syndrome (GBS) and Miller Fisher syndrome (MFS) subsequent to Campylobacter jejuni enteritis. Our study showed that patients with GBS or MFS who had previously suffered diarrhea had anti-GD3 antibodies less often than those who had not had diarrhea. Sera from patients who showed GBS or MFS with the serologic evidence of prior C. jejuni infection had anti-GD3 antibodies less frequently than sera from those without evidence of infection. Statistical analysis showed that anti-GD3 antibodies were less frequent in patients with GBS or MFS from whom C. jejuni had been isolated than were other antiganglioside antibodies, such as anti-GM1 antibodies. These results could not support the above hypothesis.

Acute Disease↗
PubMed2000

CD14+CD16+ monocyte subpopulation in Kawasaki disease.

Kawasaki disease (KD) is an acute febrile illness caused by vasculitis, occurring in early childhood. We have demonstrated that the activation of monocytes/macrophages plays a central role during acute KD. Recently, it has been reported that the CD14+CD16+ monocyte subpopulation plays a more important role in inflammation. In this study, we investigated the peripheral blood CD14+CD16+ monocyte subpopulation by flow cytometry, and serum levels of IL-10 and IL-12 using a sandwich ELISA in 28 KD patients. We also investigated this subpopulation in patients with bacterial infections, mononucleosis and anaphylactoid purpura, since the cause of KD remains unknown. We observed an increase in the number of CD14+CD16+ monocytes with acute KD, which was a positive correlation with C-reactive protein levels, and we observed only the patients with severe bacterial infections had increased this subpopulation during the acute stage among control diseases. In addition, we found that the serum levels of IL-10, but not IL-12, were higher during acute KD. These data suggest that increased peripheral blood CD14+CD16+ monocytes are part of the regulatory system of monocyte function during acute KD.

Acute Disease↗
PubMed2000

Impaired beta-cell function in the presence of reduced insulin sensitivity determines glucose tolerance status in acromegalic patients.

OBJECTIVE: Abnormal glucose tolerance is often demonstrated in acromegalic patients. Although insulin resistance is a common feature of acromegaly, it remains unclear whether the extent of insulin resistance per se determines the abnormal glucose tolerance. In order to elucidate this issue, we investigated insulin sensitivity and beta-cell function in acromegalic patients. DESIGN: Twenty-four acromegalic patients were studied in comparison with 24 healthy control subjects. To estimate insulin sensitivity and beta-cell function, we used correct homeostasis model assessment (HOMA) model, a computer-solved model. We also investigated the effects of surgical success on both parameters. RESULTS: HOMA insulin sensitivity (HOMA-%S) in the acromegalic patients was 74 +/- 51 (SD)%, significantly lower than that in 24 healthy controls (144 +/- 49%). HOMA-%S in 12 normal glucose tolerance (NGT) patients was 54 +/- 31%, not significantly different from that in impaired glucose tolerance (IGT; n = 11) or diabetes mellitus (DM; n = 1) patients (93 +/- 60%). By contrast, HOMA beta-cell function (HOMA-%beta) in the NGT acromegalic patients was 163 +/- 67%, significantly higher than the IGT/DM acromegalic patients (89 +/- 34%) and the healthy controls (72 +/- 19%). In 11 patients who achieved complete normalization of GH excess after surgery, HOMA-%S significantly increased to control ranges (from 76 +/- 26 to 159 +/- 61%) within 2 weeks after the surgical success. CONCLUSIONS: We conclude that insulin sensitivity is reduced to a similar extent in acromegalic patients with normal glucose tolerance and those with impaired glucose tolerance or diabetes. Compensatory hyperfunction of beta-cells appears to counterbalance the reduced insulin sensitivity in the acromegalic patients with normal glucose tolerance but not in those with impaired glucose tolerance or diabetes.

Acromegaly↗
PubMed2000

Hemodynamic effects of intravenous administration of olprinone hydrochloride on experimental pulmonary hypertension.

To examine acute effects of olprinone hydrochloride (CAS 106730-54-0, Coretec) on pulmonary hypertension, hypoxic pulmonary hypertension was produced in 6 adult Beagle dogs. Using this pulmonary hypertension model, single intravenous bolus injections of olprinone at doses of 10, 30 and 100 micrograms/kg were administered at 5-min intervals and hemodynamic parameters were evaluated. Heart rate increased at doses of 30 and 100 micrograms/kg, but did not change at a dose of 10 micrograms/kg. Mean aortic pressure, mean pulmonary arterial pressure, pulmonary vascular resistance and systemic vascular resistance and right ventricular stroke work index did not change at doses of 10 and 30 micrograms/kg, but they decreased significantly at a dose of 100 micrograms/kg. On the other hand, cardiac index and the first derivative value of the left ventricular pressure did not show significant change at all doses. These results indicate the vasodilating effects on peripheral and pulmonary vessels in hypoxic model at high doses of olprinone. Its application in right heart failure accompanied by pulmonary hypertension therefore is expected to yield promising results.

Animals↗
PubMed2000

Different expression of ICAM-1 and LFA-1 alpha by peripheral leukocytes during respiratory syncytial virus and influenza virus infection in young children.

We compared the expression of intercellular adhesion molecule (ICAM)-1 and lymphocyte function-associated antigen (LFA)-1 alpha (alpha) on the surfaces of peripheral immunocompetent cells of young children infected with respiratory syncytial virus (RSV) and influenza virus. Flow cytometric analysis revealed a significantly higher percentage of CD14 + monocytes/macrophages that were strongly ICAM-1-positive in the influenza group than in age-matched controls, whereas the ICAM-1 expression levels of the RSV and control groups did not differ significantly. Analysis of LFA-1alpha expression by CD3 + T lymphocytes showed a significantly higher percentage of strongly positive cells in the influenza group than in the age-matched controls. By contrast, the percentage of cells that were strongly LFA-1alpha-positive was significantly lower in the RSV group than in the age-matched controls. These results suggest that no increase of adhesion molecule expression occurs in vivo in patients with RSV infection, and also that there is little activation of peripheral blood monocytes/macrophages and T lymphocytes in young children with RSV infection.

CD3 Complex↗
PubMed2000

Molecular cloning and characterization of phosphatidylcholine transfer protein-like protein gene expressed in murine haploid germ cells.

We have isolated a cDNA clone specifically expressed in spermiogenesis from a subtracted cDNA library of mouse testis. The cDNA consisted of 1392 nucleotides and had an open reading frame of 873 nucleotides encoding a protein of 291 amino acid residues. Computer-mediated homology search revealed that the nucleotide sequence was unique but the deduced amino acid sequence had similarity to mouse phosphatidylcholine transfer protein (PCTP). We named this newly isolated gene PCTP-like protein. Northern blot analysis revealed a 1.4-kilobase mRNA expressed in the testis, kidney, liver, and intestine with the highest level in the testis. Messenger RNA expression in the testis was detected first on Day 23 in postnatal development and then increased up to adulthood. The protein, having a molecular weight of approximately 40 000, was encoded by the mRNA and was detected at the tail of the elongated spermatids and sperm by immunohistochemical staining.

Aging↗
PubMed2000

Cloning and characterization of a complementary deoxyribonucleic acid encoding haploid-specific alanine-rich acidic protein located on chromosome-X.

We have isolated a cDNA clone encoding a germ cell-specific protein from an expression cDNA library prepared from the mouse testis using testis-specific polyclonal antibodies. Northern blot analysis showed a transcript of 1.1 kilobases exclusively expressed in haploid germ cells of the testis. Sequence analysis of the cDNA revealed one long open reading frame consisting of 238 deduced amino acids, rich in basic amino acids in the N-terminal one-third that also contained the nuclear localization signal, and rich in acidic amino acids, including two type of acidic alanine-rich repeats, in the rest of the deduced protein. The protein having a molecular weight of approximately 55 kDa and an isoelectric point of pH 4.3-4.7 was also exclusively detected in the testis by Western blot analysis. As the cDNA was located on chromosome-X, Halap-X (haploid-specific alanine-rich acidic protein located on chromosome-X) was proposed for the name of the protein encoded by the cDNA. Immunohistochemical observation revealed that the Halap-X protein was predominantly present in the nucleoplasm of round spermatids but gradually decreased as spermatids matured, followed by the subsequent appearance in the cytoplasm of elongating spermatids. Thus, the Halap-X protein was transferred from the nuclei to the cytoplasm during the spermatid maturation when the chromatin condensation and transformation of the nuclei occurred. The Halap-X may facilitate specific association of nuclear DNA with some basic chromosomal proteins and play important roles in the process of chromatin condensation.

Amino Acid Sequence↗
PubMed2000

Isolation and characterization of a haploid germ cell-specific novel complementary deoxyribonucleic acid; testis-specific homologue of succinyl CoA:3-Oxo acid CoA transferase.

We have isolated a cDNA clone encoding a mouse haploid germ cell-specific protein from a subtracted cDNA library. Sequence analysis of the cDNA revealed high homology with pig and human heart succinyl CoA:3-oxo acid CoA transferase (EC 2.8.3.5), which is a key enzyme for energy metabolism of ketone bodies. The deduced protein consists of 520 amino acid residues, including glutamate 344, known to be the catalytic residue in the active site of pig heart CoA transferase and the expected mitochondrial targeting sequence enriched with Arg, Leu, and Ser in the N-terminal region. Thus, we termed this gene scot-t (testis-specific succinyl CoA:3-oxo acid CoA transferase). Northern blot analysis, in situ hybridization, and Western blot analysis demonstrated a unique expression pattern of the mRNA with rapid translation exclusively in late spermatids. The scot-t protein was detected first in elongated spermatids at step 8 or 9 as faint signals and gradually accumulated during spermiogenesis. It was also detected in the midpiece of spermatozoa by immunohistochemistry. The results suggest that the scot-t protein plays important roles in the energy metabolism of spermatozoa.

Amino Acid Sequence↗
PubMed2000

The relationship between angioblastoma (Nakagawa) and tufted angioma: report of four cases with angioblastoma and a literature-based comparison of the two conditions.

We report four recent cases of angioblastoma (Nakagawa). Histopathologic examinations of all cases revealed dispersed islets of clear marginal lobules of varying sizes in the dermis. Neoplastic endothelioid cells with moderate atypia and enlarged capillaries containing erythrocytes were found in the conglomerates. Recently, the features of this disease have been compared to the tufted angioma that has been reported in Europe and the U.S. Our evaluation suggests that these two diseases are very likely the same. We suggest that this disease should be called "angioblastoma" in agreement with the first report of this disease by Nakagawa.

Adolescent↗
PubMed2000

Two cases of confluent and reticulate papillomatosis: successful treatments of one case with cefdinir and another with minocycline.

The present report presents two cases of confluent and reticulate papillomatosis. Case 1 was a 24-year-old man who had suffered from skin eruptions for six months, and Case 2 was a 19-year-old woman who had had this disease for three days. In both patients, reticular dark brown papules, accompanied by mild keratosis and infiltration, spread from the trunk to the neck and upper arm. Direct light microscopy did not detect the presence of any fungi, and histopathological examinations confirmed hyperkeratosis, acanthosis, papillomatosis, and mild small-round-cell infiltration. Thus, these patients were diagnosed as confluent and reticulate papillomatosis. Neither one had diabetes or thyroid dysfunction. In Case 1, cefdinir was effective, and in Case 2, minocycline hydrochloride and ketoconazole were effective. To the best of our knowledge, this was the first documented case of confluent and reticulate papillomatosis responding to cefdinir.

Adult↗
PubMed2000

Changes in plasma serotonin concentration and acceleration plethysmograms in patients with Raynaud's phenomenon after long-term treatment with a 5-HT2 receptor antagonist.

High blood serotonin concentrations have been reported in patients with Raynaud's phenomenon and a relationship has been suggested. Because of the difficulty in evaluating Raynaud's phenomenon objectively, a possible correlation between blood serotonin concentrations and clinical findings has not yet been evaluated. We measured plasma serotonin concentrations and acceleration plethysmograms (APG) before and one year after administration of a serotonin receptor antagonist. Twenty-seven patients with either collagen disease or diseases associated with Raynaud's phenomenon were given a combined 5-HT2 and serotonin receptor antagonist, sarpogrelate hydrochloride. Plasma serotonin concentrations were determined before and after administration and the APG d/a value was measured as an index of peripheral hemodynamics. These values were compared with the clinical symptoms of the patients. After one year of treatment, the subjective symptoms improved in 59.3% of patients who has Raynaud's phenomenon. The pretreatment plasma serotonin concentrations of the study patients were significantly higher than those of the normal controls, but became significantly decreased following 5-HT2 administration. However, there was no clear-cut relationship with the clinical symptoms. The pre-treatment APG d/a value of the patients was significantly lower than that of the normal controls, although there was no significant difference after administration when analyzed as an entire group or in a subset of patients whose symptoms did not subjectively improve or worsened after one year of treatment. In the subset in whom the subjective symptoms improved, however, the value significantly increased following administration, suggesting an improvement in peripheral hemodynamics. These results suggest the possibility that APG can be used as an objective index of peripheral hemodynamics.

Adult↗
PubMed2000

A case of dermatomyositis associated with mechanic's hand.

A 67-year-old man was referred to the Department of Internal Medicine at Tokyo Medical University with interstitial pneumonia in July 1999. He presented with keratotic plaques on both palsm and on the ventral and lateral sides of his fingers. Erythematous keratosis was observed on the dosal aspect of his fingers and metatarsophalangeal (MP) joints. Edematous erythema was seen on the patient's chest, back, and the extensor surfaces of his arms. Electromyography revealed a myogenic pattern and an increased level of myogenic enzymes was found in the blood. Histological findings of the ventral sides of his fingers showed hyperkeratosis and parakeratosis of the dermal tissue and liquefaction degeneration of the basal layer at the papilla. Based on these findings, the patient was given a diagnosis of dermatomyositis associated with mechanic's hand. A systemic examination confirmed interstitial pneumonia and carcinoma of the duodenal papilla. Mechanic's hand is a type of dermatitis associated with myopathy first reported by Stahl et al. in patients with collagen disease. We report herein the first documented case of mechanic's hand in Asians.

Adenocarcinoma↗
PubMed2000

A case of varicella complicated by cellulitis and scarlet fever due to Streptococcus pyogenes.

We report a 4-year-old boy with cellulitis and scarlet fever due to streptococcal infection following the onset of varicella. He developed a painful ulcer and subcutaneous induration on the left shoulder and a small, light-red-colored rash on the trunk at approximately the same time as the development of vesicles over the entire body. Streptococcus pyrogenes was isolated from samples from the posterior intranasal space and the ulcer on the shoulder. The clinical symptoms improved with the administration of antibiotics and intravenous drip infusion, but it took approximately one month from the first visit for the subcutaneous induration to disappear and the ulcer to heal with epithelialization. The complication of secondary streptococcal infection in varicella is relatively rare in Japan, but in Western countries there have been many reported cases of life-threatening necrotizing fasciitis and necrotizing pyomyositis due to secondary streptococcal infection following varicella. Close attention should be paid to streptococcal infection as a complication of varicella.

Cellulitis↗
PubMed2000

Isolated absence of F waves and proximal axonal dysfunction in Guillain-Barré syndrome with antiganglioside antibodies.

OBJECTIVES: To investigate the pathophysiology of selective absence of F waves and its relation with antiganglioside antibodies in Guillain-Barré syndrome (GBS). Some patients with GBS show the absence of F waves as an isolated conduction abnormality, which has been interpreted as demyelination in the proximal nerve segments. METHODS: In 62 consecutive patients with GBS, sequential nerve conduction and F wave studies were reviewed, and antibodies against ganglioside GM1, GM1b, GD1a, GalNAc-GD1a, GD1b, and GQ1b were measured by an enzyme linked immunosorbent assay. RESULTS: In the first electrophysiological studies, isolated absence of F waves was found in 12 (19%) patients. Sequential studies in 10 of these patients showed two electrophysiological sequel patterns; rapid restoration of F waves (six patients), and persistent absence of F waves with distal motor nerve degeneration (acute motor axonal neuropathy, four patients). None of the 10 patients showed evidence of demyelination in the proximal, intermediate, or distal nerve segments throughout the course. Of the 62 patients, IgG antibodies against GM1, GM1b, GalNAc-GD1a, or GD1b were significantly associated with the electrodiagnosis of acute motor axonal neuropathy, and patients with these antibodies more often had isolated absence of F waves than patients without them (11 of 36 (31%) v one of 26 (4%); p<0.01). Eleven of the 12 patients with isolated absence of F waves had positive serology for one or more antiganglioside antibodies. CONCLUSIONS: In GBS with antiganglioside antibodies, isolated absence of F waves is a frequent conduction abnormality especially in the early phase of the disease, and may be caused by axonal dysfunction, such as physiological conduction block or axonal degeneration at the nerve roots.

Adolescent↗
PubMed2000

The regression of left ventricular hypertrophy by imidapril and the reduction of serum procollagen type III amino-terminal peptide in hypertensive patients.

Angiotensin-converting enzyme (ACE) inhibitors are known to be the most effective antihypertensive drugs for reducing left ventricular mass in hypertensives when compared to other classes of drugs. In the present study, we evaluated the effects of imidapril, an ACE inhibitor, on serum procollagen type III amino-terminal peptide (PIIIP) levels as well as the left ventricular mass index (LVMI). The subjects consisted of 15 patients (12 men and 3 women) in the outpatient clinic of our hospital who were diagnosed as essential hypertensives and who had not been treated with any antihypertensive medication prior to the study. Left ventricular hypertrophy was observed in all of the patients, ie., LVMI >110 g/m2 in men and >106 g/m2 in women. Blood pressure, LVMI, and serum PIIIP levels were measured before and after treatment with imidapril for 6 months. The starting dose of imidapril was 5 mg, and this was increased to 10 mg. Finally, 1 mg of trichlormethiazide was added to obtain adequate control of blood pressure. Blood pressure significantly decreased in 12 patients, and the mean LVMI decreased significantly from 153.1 +/- 9.0 to 135.4 +/- 6.3 (p< 0.01) after treatment. The changes in LVMI and PIIIP levels with treatment had significant correlation (r=0.639, p< 0.05). The present study showed that imidapril reduces the left ventricular mass in hypertensives after 6 months of treatment, and that this may at least in part be due to a decrease in the collagen content of the hypertrophied heart, suggesting that serum PIIIP levels are a useful marker of the regression of left ventricular hypertrophy.

Adult↗