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Biomedical subjects

K Hamaguchi

Publications and source records attributed to K Hamaguchi.

At least 55 records · Page 3Linked to original sources
PubMed1997

Hepatic denervation induces supersensitivity to terbutaline of the hepatic arterial system in conscious dogs.

The effects of hepatic denervation on liver blood flow and the influence of the denervation on the hemodynamic response to exogenously administered agents remain equivocal. This study examined the effects of the beta 2-adrenoceptor agonist, terbutaline, on liver blood flow and how these effects were influenced by surgical hepatic denervation in a conscious canine model. Two weeks after denervation, hepatic arterial flow, portal venous flow, and aortic blood flow were measured during intravenous infusion of terbutaline at 0.1, 0.2, 0.4, and 0.8 microgram/kg/min, and responses were compared between the hepatic denervated and sham-operated dogs. Implantable transit-time ultrasonic flowmeter and probes were used. Hepatic arterial flow increased dose-dependently in response to terbutaline in denervated dogs, while it remained unchanged in control dogs except at the highest dose of terbutaline. The increase in hepatic arterial flow of denervated dogs was significantly greater than that of controls at all doses of terbutaline. Aortic blood flow-indexed hepatic arterial flow in response to terbutaline also differed substantially between the two groups. Terbutaline produced a marked dose-dependent increase of portal venous flow similarly in both groups. These results suggest that the beta 2-adrenoceptor agonist terbutaline should be effective for increasing liver blood flow and could lessen postoperative liver ischemia. We speculate that hepatic denervation induces supersensitivity of the hepatic arterial system to intravenous terbutaline.

Adrenergic beta-Antagonists↗
PubMed1997

Distal pancreatectomy with en bloc resection of the celiac artery for carcinoma of the body and tail of the pancreas.

CONCLUSION: Combined resection of the celiac artery with a distal pancreatectomy (DP) increases the resectability and improves the overall prognosis of patients with locally advanced ductal cancer of the body and tail of the pancreas. BACKGROUND: Carcinoma of the body and tail of the pancreas is often unresectable because of invasion to adjacent organs. We evaluated a DP including an en bloc resection of the celiac artery ("extended"), for pancreatic cancer that had invaded the common hepatic and/or celiac arteries. METHODS: Six cases of an "extended" DP were compared with 19 cases of a "standard" DP for pancreatic ductal carcinoma in terms of clinical and pathologic findings, perioperative course, and long-term outcome. We also compared the survival rate of these two groups with a third group consisting of 22 patients with unresectable pancreatic ductal carcinoma. RESULTS: The mean operative time, postoperative serum aspartate aminotransferase concentration, and length of hospital stay did not significantly differ between the "extended" and "standard" DP groups. The cumulative 1- and 3-yr accumulated survival rates for the "extended," "standard," and unresectable groups were 40.0, 33.3, and 5.4, and 20.0, 16.6, and 0%, respectively. Statistically significant differences (p < 0.01) existed between the "extended" and unresected groups.

Adult↗
PubMed1997

Comparative study of clinical effects between plasma adsorption and double filtration plasmapheresis in patients with myasthenia gravis.

Plasma exchange (PE) has been one of the most powerful treatments for patients with myasthenia gravis (MG) since Pinching et al. reported its clinical usefulness in 1976, despite the need for supplemental human plasma. However, new apheresis techniques, e.g., plasma adsorption (PA) and double filtration plasmapheresis (DFPP), which do not need human plasma, were developed and have been introduced for clinical use in MG. We compared the effects of these plasma purification therapies in patients with MG and found that DFPP improved such subjective symptoms as chest compression and general fatigue better than PA while both of them could decrease the serum level of acetylcholine receptor (AChR) antibodies and relieve objective muscle weakness to a similar degree. It may be that DFPP can remove some circulating pathogenic factors other than AChR antibodies more efficiently than PA.

Adult↗
PubMed1997

[Tumor reduction in advanced renal cell carcinoma with tumor thrombus by renal embolization, interferon-alpha and UFT. A case report].

A 73-year-old man with renal cell carcinoma involving the left renal vein was treated with the embolization of the left renal artery followed by interferon-alpha and UFT. Computerized tomography revealed 53% reduction of the primary lesion and 47% reduction of the tumor thrombus 40 days after treatment. The histopathological study revealed marked lymphocyte infiltration and necrosis of the tumor after nephrectomy.

Aged↗
PubMed1997

[A case of primary antiphospholipid antibody syndrome with severe nephrotic syndrome showing remarkable endothelial cell damage in the capillary lumen].

A 25-year-old woman complained of anasarca and was admitted to Sakura National hospital on the presumptive diagnosis of nephrotic syndrome with 10.7 g of 24-hour urinary protein. At first, lupus nephritis with antiphospholipid antibody syndrome was suspected because of prolongation of APTT, existence of lupus anticoagulant and elevation of serum anticardiolipin antibody titer (IgM) in addition to positive ANA, lymphocytopenia and the biologically false positive test for syphilis (BFPTS). On day 28 of hospitalization, renal biopsy findings revealed severe endocapillary cell damage, such as swelling and proliferation of endothelial cells, fragmentation and double contour of the basement membrane walls, which were located only in the capillary lumens with a few thrombi. Immunofluorescent micrography revealed the absence of specific immunoglobulin or complement deposit. Therefore, the diagnosis of lupus nephritis was negated as these findings were suggestive of characteristic glomerulopathy due to primary antiphospholipid antibody syndrome. She was treated initially with oral prednisolone 60 mg and intravenous infusion of heparin 20,000 units daily. Moreover, cyclophosphamide 750 mg was administered intravenously as pulse therapy on day 13 as her serum level of CH50 had fallen suddenly, and hemodialysis was necessary because her renal function had deteriorated and she was suffering from cough and orthopnea with overhydratin. After the combined therapy, BFPTS disappeared and APTT returned to the normal range: dialysis treatment was not required further after the 4th hemodialysis. Thereafter, renal function improved and complete remission of nephrotic syndrome was obtained. This patient was a case of primary antiphospholipid antibody syndrome in which endothelial cell damage was located exclusively in the capillary lumens and pulse cyclophosphamide therapy in addition to prednisolone and anticoagulant was effective. We present this instructive case to promote understanding of the pathogenesis of primary antiphospholipid antibody syndrome.

Adult↗
PubMed1997

[Two cases of encephalo-myelo-radiculoneuropathy, triggered by herpes simplex virus type-1 infection].

We report two cases of encephalo-myelo-radiculoneuropathy, triggered by herpes simplex virus type-1 (HSV-1) infection. Patient 1 (a 25-year-old man) and patient 2 (a 52-year-old man) were admitted to the hospital because of fever, headache, abnormal behavior, and loss of consciousness. In each case, cerebrospinal fluid (CSF) showed lymphocytic pleocytosis with protein elevation, and serum and CSF IgG antibody titers to HSV-1 were elevated markedly. Although patient 1 was treated with aciclovir in the early phase of encephalitis, he developed severe quadriparesis as a sequela. Patient 2 was treated with a combination of aciclovir and corticosteroids, and he recovered completely about 4 months after the onset of the disease. There have been only a few reports of encephalo-myelo-radiculoneuropathy triggered by HSV-1 infection. Early corticosteroid therapy was effective in our patients with post-HSV-1 infectious encephalo-myelo-radiculoneuropathy. These two patients were studied with flow cytometry for peripheral blood lymphocyte subsets during the disease course. In the active stage of the disease, the helper-inducer (CD4 + CD29+), activated T cell (CD4 + CD25+), and cytotoxic/NK (CD8 Dull + CD11b Bright+) subsets were increased compared with subsets in controls. An interesting finding was mismatched responses with an increased suppressor-inducer (CD4 + Leu8+) subset and a decreased suppressor-effecter (CD8 Bright+ CD11b Dull+) subset, indicating a possible autoimmune character of encephalo-myelo-radiculoneuropathy triggered by viral infection.

Acyclovir↗
PubMed1996

Aging and superoxide dismutase activity in cerebrospinal fluid.

We investigated superoxide dismutase (SOD) activity in human cerebrospinal fluid (CSF) as an index of the aging process in the central nervous system (CNS). The subjects were 61 individuals aged 21-77 years, comprising 24 men and 37 women without organic disorders of the nervous system. SOD activity in CSF was measured by the nitrite method modified by Oyanagui. The results showed that SOD activity in CSF gradually increased with age and that the values of SOD activity after the fifth decade were significantly higher than those in the third and fourth decades. It might suggest that the productivity of SOD in the CNS gradually increased with age due to stimulation of various types of oxidative stress which accumulated in vivo especially after the fifth decade.

Adult↗
PubMed1996

Mouse-Musashi-1, a neural RNA-binding protein highly enriched in the mammalian CNS stem cell.

There is increasing interest in the role of RNA-binding proteins during neural development. Drosophila Musashi is one of the neural RNA-binding proteins essential for neural development and required for asymmetric cell divisions in the Drosophila adult sensory organ development. Here, a novel mammalian neural RNA-binding protein, mouse-Musashi-1, was identified based on the homology to Drosophila Musashi and Xenopus NRP-1. In the developing CNS, mouse-Musashi-1 protein was highly enriched in the CNS stem cell. Single-cell culture experiments indicated that mouse-Musashi-1 expression is associated with neural precursor cells that are capable of generating neurons and glia. In contrast, in fully differentiated neuronal and glial cells mouse-Musashi-1 expression is lost. This expression pattern of mouse-Musashi-1 is complementary to that of another mammalian neural RNA-binding protein, Hu (a mammalian homologue of a Drosophila neuronal RNA-binding protein Elav), that is expressed in postmitotic neurons within the CNS. In vitro studies indicated that mouse-Musashi-1 possesses binding preferences on poly(G) RNA homopolymer, whereas Hu is known to preferentially bind to short A/U-rich regions in RNA. Based on their differential expression patterns and distinct preferential target RNA sequences, we believe that the mouse-Musashi-1 and Hu proteins may play distinct roles in neurogenesis, either through sequential regulatory mechanisms or differential sorting of mRNA populations during asymmetric division of neural precursor cells.

Amino Acid Sequence↗
PubMed1996

Thymus-related liposarcoma: report of a case and review of the literature.

We report herein the case of a 77-year-old woman who was admitted to our hospital for further evaluation of an abnormal shadow in the right upper mediastinum that had been revealed by a routine chest X-ray. Computed tomography (CT) and magnetic resonance imaging (MRI) scans confirmed the presence of a thymic tumor, but did not show any evidence of invasion into the central vessels or adjacent structures. Thus, an extended thymectomy with resection of the tumor was performed. Microscopically, normal thymic tissue was found among the tumor cells, and a pathological diagnosis of well-differentiated liposarcoma was established. From the operative and microscopic findings, it is apparent that the tumor was related to the thymus. Postoperative irradiation of 60 Gy was delivered to the operative site and the patient has remained free of disease for 29 months since the operation.

Aged↗
PubMed1996

Monoclonal antibodies specific to the integral membrane protein P0 of bovine peripheral nerve myelin.

Two monoclonal antibodies (mAbs), 58A and 46E, were generated against the major protein P0 of bovine peripheral nervous system myelin (PNSM). The reactivities of the mAbs were assessed by enzyme-linked immunosorbent assay (ELISA), Western blot, and immunohistochemistry. Both mAbs, 58A and 46E, reacted to PNSM of bovine, human, rat and rabbit, but not to chicken PNSM or the brains of rat and rabbit. In the Western blot, these mAbs showed specific binding to bovine P0 as well as deglycosylated P0, but not to myelin-associated glycoprotein (MAG) of bovine spinal cord. The analyses of the lysylendopeptidase-digested peptides of bovine P0 revealed that the epitopes for the mAbs 58A and 46E were located on the amino acid residues 68-79 and 210-216, respectively. Since the mAbs 58A and 46E recognize the extracellular domain and the cytoplasmic domain of P0, respectively, they could be useful for studies on P0's role in myelin formation, its adhesive properties, and functions of the N-terminal extracellular and C-terminal cytoplasmic domains of the protein.

Amino Acid Sequence↗
PubMed1996

Different contribution of HLA-DR and -DQ genes in susceptibility and resistance to insulin-dependent diabetes mellitus (IDDM).

Previous studies have indicated that certain alleles of HLA-DR and -DQ genes were strongly associated with susceptibility and resistance to insulin-dependent diabetes mellitus (IDDM), and the role of DQ molecule in IDDM has been suggested. To further clarify the association of DQ alleles with IDDM, we determined the nucleotide sequences of full-length cDNA from 13 DQA1 alleles and 14 DQB1 alleles. The sequencing analysis revealed sequence polymorphisms outside the hypervariable region of DQ genes. We then analyzed the DQA1 and DQB1 polymorphisms along with that of DRB genes in 86 B-lymphoblastoid cell lines (B-LCLs) from various ethnic groups and in healthy unrelated Japanese and Norwegian individuals. The allelic and haplotypic distributions in each population revealed the characteristic haplotypic formation in the HLA class II region. HLA genes in 139 Japanese and 100 Norwegian IDDM patients were analyzed. DQB1*0301 was negatively associated with IDDM in both ethnic groups, irrespective of associated DRB1 and DQA1 alleles. In DQB1*0302 positive populations, which represented a positive association with IDDM in both ethnic groups, DRB1*0401, *0404, *0802 haplotypes increased in the patients, whereas DRB1*0406 haplotype decreased. Considering about the hierarchy in DRB1 alleles with IDDM susceptibility (DRB1*0401>*0404>*0403 in Norwegian and DRB1*0802>*0403>*0406 in Japanese), the genetic predisposition to IDDM is suggested to be defined by the combination of DR-associated susceptibility and DQ-associated susceptibility and by the DQ-associated resistance which is a dominant genetic trait.

Alleles↗
PubMed1996

PDX-1 induces insulin and glucokinase gene expressions in alphaTC1 clone 6 cells in the presence of betacellulin.

The pancreatic beta- and alpha-cells are developmentally related to each other but reveal diverse gene expression patterns. Among the two important transcription factors for insulin gene expression, IEF1 is present both in alpha- and beta-cells, but PDX-1/IPF1/STF-1/IDX-1, a homeodomain-containing transcription factor, is present in beta-cells but not in alpha-cells. To elucidate the function of PDX-1 in the expression of beta-cell-specific genes, we established stable alphaTC1 clone 6 (alphaTC1.6)-derived transfectants expressing PDX-1 and examined the changes in the gene expression patterns in them. The exogenous expression of PDX-1 in alphaTC1.6 cells alone could induce islet amyloid polypeptide (IAPP) mRNA expression in the cells but not the expression of insulin, glucokinase, or GLUT2 gene. However, when betacellulin was added to the medium, the PDX-1-expressing alphaTC1.6 cells, but not the control alphaTC1.6 cells, came to express insulin and glucokinase mRNAs. This did not occur with other growth factors such as epidermal growth factor, transforming growth factor alpha, and insulin-like growth factor I. GLUT2 mRNA remained undetectable in the PDX-1--expressing alphaTC1.6 cells. These observations demonstrate the potency of PDX-1 for the expression of the insulin, glucokinase, and IAPP genes and suggest that certain regulatory factors, which can partially be modified by betacellulin, also contribute to the beta-cell specificity of gene expression.

Amyloid↗
PubMed1996

[A case of familial amyotrophic lateral sclerosis with markedly decreased accumulation on 123I-MIBG myocardiac scintigraphy and atonic bladder].

A 63-year-old Japanese woman with familial amyotrophic lateral sclerosis (ALS) showed cardiac hypofunction and neurogenic bladder. Her autonomic function was evaluated by means of 123I-metaiodobenzylguanidine (MIBG) cardiac scintigraphy and urodynamic study. (1) MIBG scintigraphy: Both early and late imagings showed severe defects of myocardial 123I-MIBG accumulation despite the normal accumulation of 201thallium. (2) Urodynamic study: Atonic bladder was observed on cystometry. These data indicate that both sympathetic and parasympathetic nerve functions were disturbed, suggesting the possibility that autonomic disturbance in familial ALS may differ from those in sporadic ALS, in which increased sympathetic nervous function has been reported.

3-Iodobenzylguanidine↗
PubMed1996

[Rhabdomyolysis related-acute renal failure in a patient with hyperosmolar nonketotic diabetic coma (HNKC): demonstration of myoglobin casts after normalization of renal function].

We report a patient with rhabdomyolysis secondary to hyperosmolar nonketotic diabetic coma (HNKC), who progressed to acute renal failure. A 43-year-old male with diabetes mellitus for three years was admitted to our hospital because of loss of consciousness. The laboratory findings at admission were as follows: serum glucose 1792 mg/dl, serum Na 129 mEq/1, BUN 71 mg/d1, serum creatinine 3.3 mg/d1, CPK 715 IU/1, plasma osmolality 370 mOsm/1, and negative urine ketone bodies. A diagnosis of HNKC was made. On the 2nd day, he had oliguria and the serum creatinine increased despite adequate treatment of HNKC by the administration of intravenous fluid and insulin. On the 4th day, CPK reached 47,300 IU/1, and serum myoglobin was also increased, indicating rhabdomyolysis. His renal function improved gradually and was almost normalized on the 20th day. Renal biopsy on the 23rd day showed myoglobin at the distal renal tubules, which appeared to be involved in the pathogenesis of renal failure by rhabdomyolysis. However, we found little abnormality association with diabetic nephropathy in the renal tissue. Since HNKC is known to induce acute renal failure rarely without diabetic nephropathy, these findings suggested that the acute renal failure was caused mainly by the rhabdomyolysis. Acute renal failure induced by rhabdomyolysis in patients with HNKC is rare, but fatal. The present study showed that the measurement of serum CPK and urine myoglobin was helpful for early diagnosis. Only 12 cases have been reported to have developed renal failure due to rhabdomyolysis among patients with HNKC. To our knowledge, we demonstrated for the first time that myoglobin at the distal renal tubules after renal function was normalized.

Acute Kidney Injury↗