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Biomedical subjects

S Horiuchi

Publications and source records attributed to S Horiuchi.

At least 307 records · Page 17Linked to original sources
PubMed1988

[Postoperative hydrocele testis as a complication of high ligation of internal spermatic vein].

We reviewed 785 patients with varicocele testis who underwent high ligation of internal spermatic vein at Kasukabe City Hospital between 1969 and 1985, and found only 3 patients suffering from postoperative hydrocele testis. Analysis of the hydrocele content in one case revealed a high protein level, which suggested that the etiology of the hydrocele after high ligation is of lymphatic origin, so that it is important to preserve the lymphatics of spermatic cord in order to prevent postoperative hydrocele.

Adult↗
PubMed1988

Age-specific growth rates: the legacy of past population dynamics.

Recent developments in population mathematics have focused attention on a function that is widely available but rarely examined: the set of age-specific growth rates in a population. In particular, this set of rates is sufficient for translating the current birth rate and age-specific mortality rates into the current age distribution. This growth-rate function contains all of the pertinent features of a population's demographic history that are required to relate major demographic functions for a particular period to one another. This article presents an expression for the age-specific growth rate and uses it to derive an equation for age distribution. We show how the value of the age-specific growth rate is determined by a population's demographic past and present various sets of growth rates corresponding to stylized demographic scenarios. Several noteworthy sets of growth rates observed in human populations are discussed. Finally, we explain why age-specific growth rates make it possible to determine the age distribution solely from information on current demographic conditions.

Adolescent↗
PubMed1987

Distinction in the mode of receptor-mediated endocytosis between high density lipoprotein and acetylated high density lipoprotein: evidence for high density lipoprotein receptor-mediated cholesterol transfer.

The interactions of high density lipoprotein (HDL) and acetylated high density lipoprotein (acetyl-HDL) with isolated rat sinusoidal liver cells have been investigated. Cellular binding of 125I-acetyl-HDL at 0 degrees C demonstrated the presence of a specific, saturable membrane-associated receptor. This receptor was affected neither by formaldehyde-treated albumin nor by low density lipoprotein modified either by acetylation or malondialdehyde, ligands known to undergo receptor-mediated endocytosis by the cells, indicating that the receptor for acetyl-HDL constitutes a distinct class among the scavenger receptors for chemically modified proteins. Parallel binding experiments using 125I-HDL also revealed the presence on these cells of a receptor for unmodified HDL. The ligand specificities of these two receptors were similar to each other except that the acetyl-HDL receptor was sensitive to polyanions such as dextran sulfate and fucoidin. Interaction of HDL with the cells at 37 degrees C was totally different from that of acetyl-HDL. Cellular binding of HDL was not accompanied by subsequent intracellular degradation of its apoprotein moiety, whereas its cholesterol moiety was significantly transferred to the cells. In contrast, acetyl-HDL was endocytosed and underwent lysosomal degradation as a holoparticle. This shift in receptor-recognition from the HDL receptor to the acetyl-HDL receptor was accomplished by acetylation of approximately 8% of the total lysine residues of HDL apoprotein. This unique difference in endocytic behavior between HDL and acetyl-HDL suggests a potential link of the HDL receptor to HDL-mediated cholesterol transfer in sinusoidal liver cells.

Acetylation↗
PubMed1987

Overproduction of gene products by the super-high-copy-number plasmid pNR333.

The plasmid pNR333 is a kanamycin-resistant, deletion derivative of pNR113 with an extremely high copy number in Escherichia coli and in Proteus mirabilis. In order to determine the usefulness of pNR333 as a replication gene of vector, the genes encoding chloramphenicol acetyl-transferase (CAT) and beta-galactosidase (beta-gal) were cloned individually into both pNR333 and other low-copy-number plasmids. The expression of the cloned genes was compared by measuring the specific activity of each enzyme and the amounts of the proteins produced. A hybrid plasmid pNR333-cat expressed 53 times as much activity of CAT as the low-copy plasmid S-a which had a copy number of four. The lacZ gene cloned in pNR333 produced 17 times as much beta-gal as in the low-copy-number plasmid pNR1150. These results suggest that pNR333 is a useful vector plasmid for producing a large amount of polypeptides in E. coli hosts.

Acetyltransferases↗
PubMed1987

Identification of the DNA sequence required for transposition immunity of the gamma delta sequence.

A plasmid containing the transposon gamma delta sequence was immune to further insertion of gamma delta (transposition immunity). Plasmids carrying a fragment containing either 0.2 kilobase pairs of the gamma end or 0.4 kilobase pairs of the delta end of the gamma delta sequence were immune, and other parts of the gamma delta sequence did not confer immunity. The terminal 38-base-pair (bp) sequence of the delta end of the gamma delta was sufficient to confer immunity, the 38-bp sequence of the gamma end conferred only moderate immunity, and the terminal 35-bp sequence, which was completely identical at both the gamma and delta ends, was insufficient to confer immunity.

Base Sequence↗
PubMed1987

Biological features of the skin of the pika, Ochotona rufescens rufescens: histological structure and enzymatic histochemical reactivity.

To examine the usefulness of the pika, Ochotona rufescens rufescens, as an experimental animal for skin irritability tests, the histological structure and enzymatic histochemical reactivity of pika skin were investigated. The pika had a hair cycle similar to that of the rabbit. The skin and epidermis of the pika trunk were 1.16mm and 29.5 microns thick, on the average, respectively. Both of them were the thickest in the dorsal region followed by the interscapular area, while they were the thinnest in the abdominal region. In the epidermis of the pika, the strata corneum, granulosum, spinosum and basale were rather clearly distinguished. The cell arrangement in the stratum basale was more compact than that in the rabbit. Dermal mast cells, which are distributed in the stratum reticulare in rabbits and guinea pigs, were distributed in the stratum papillare right beneath the epidermis. The mast cell of the pika in the TEM images had granules of low electron density and with relatively long microvilli and rather large mitochondria. The activities of the enzymes, SDH, MDH, LDH, beta HBDH, alpha GPDH, ALD, G6PDH and GPR, in the hair follicles and sebaceous glands of the pika were similar to those of the rabbit.

Animals↗
PubMed1987

[Prophylactic intravesical chemotherapy in bladder tumors after surgery of upper tract urothelial carcinoma].

Sixteen patients with upper tract urothelial carcinoma underwent intravesical chemotherapy usually at 2 week intervals in the first year and at 4 week intervals in the second year after nephrouretectomy. For bladder instillation 10 mg mitomycin C in 20 ml saline was used on 7 patients, 5 mg carboquone and 100 mg cytosine arabinoside in 40 ml saline on 5 patients and 30 mg adriamycin in 40 ml saline on 4 patients. Two (12.5%) of the 16 patients developed bladder tumors within 2 years after surgery, but 11 (42.3%) of the 26 patients with upper tract urothelial carcinoma who did not receive intravesical chemotherapy suffered from bladder tumor within 2 years after surgery. Prophylactic intravesical chemotherapy reduced significantly (p less than 0.1) the incidence of bladder tumor after the surgery of renal pelvic and ureteral tumors.

Administration, Intravesical↗
PubMed1987

[Primary adenocarcinoma of the female urethra: report of two cases].

Two cases of primary adenocarcinoma of the female urethra are reported. Case 1 was a 75-year-old female presenting with the complaint of genital bleeding. Physical examination revealed a pea-sized tumor in the urethral meatus. Tumor resection was performed under the preoperative diagnosis of caruncles, but, histopathological examination revealed adenocarcinoma. She was readmitted because of recurrence of tumor 7 months after the first operation. En bloc resection including the bladder, urethra and uterus was done followed by ileal conduit for urinary diversion. Case 2 was an 85-year-old female presenting with the complaint of macroscopic hematuria. Physical examination revealed a thumb's-head-sized tumor in the urethral meatus and also the left enlarged inguinal lymph nodes. Tumor resection and biopsy of the left inguinal lymph nodes were performed. Histopathological examination revealed adenocarcinoma. Postoperative irradiation to the left inguinal lymph nodes was given to a total dose of 4,000 rads. Ninety-two cases of primary adenocarcinoma of the female urethra in the Japanese literature including our cases are reviewed.

Adenocarcinoma↗
PubMed1987

[Bladder instillation of verapamil as a means of enhancing the efficacy of chemotherapy in superficial bladder carcinoma: influence of bladder instillation of verapamil on the cardiovascular system].

Although it is well known that calcium antagonists in vitro possess enhancing effects on anti-tumor drugs, their clinical use is limited on account of side effects on the cardiovascular system. In the present study, the authors attempted the instillation of Verapamil (calcium antagonist) combined with anti-tumor drugs into the bladder for the treatment of superficial bladder carcinoma. The dosage of Verapamil necessary for maintaining an effective concentration for enhancement of the anti-tumor drug was determined and the influences of bladder instillation of Verapamil on the cardiovascular system and on the bladder were studied. The results obtained were as follows: the use of 5 mg of Verapamil was able to maintain an effective concentration (10(-5) M) for enhancement of anti-tumor drugs for at least 2 h. Absorption of Verapamil from the bladder to the vascular system was minimal. No influence on the cardiovascular system or on the bladder was observed. The results of the present study encourage us to pursue the clinical use of Verapamil combined with anti-tumor drugs for the treatment of superficial bladder carcinoma.

Administration, Intravesical↗
PubMed1986

Scavenger receptor for malondialdehyde-modified high density lipoprotein on rat sinusoidal liver cells.

We report here the presence of a membrane-associated receptor which mediates endocytic uptake of malondialdehyde-modified high density lipoprotein (MDA-HDL) on sinusoidal liver cells. Binding of [125I]MDA-HDL to the cells was followed by internalization and degradation in lysosomes. The binding and lysosomal degradation of [125I]MDA-HDL were effectively inhibited by unlabeled MDA-HDL and acetyl-HDL. However, formaldehyde-treated serum albumin or low density lipoprotein modified either by acetylation or malondialdehyde, ligands known to undergo receptor-mediated endocytosis by sinusoidal liver cells, did not affect the binding of [125I]MDA-HDL to the cells. These results indicate that a receptor for MDA-HDL is described as a distinct member among the scavenger receptors for chemically modified proteins.

Acetylation↗
PubMed1986

Scavenger receptor for aldehyde-modified proteins.

This paper describes an unexpectedly broad ligand specificity of a scavenger receptor of sinusoidal liver cells that is responsible for endocytic uptake of formaldehyde-treated bovine serum albumin (f-Alb). Binding of 125I-f-Alb to the isolated cells was effectively inhibited by bovine serum albumin (BSA) modified with aliphatic aldehydes such as glycolaldehye, DL-glyceraldehyde, and propionaldehyde whereas albumin preparations modified by aromatic aldehydes such as pyridoxal, pyridoxal phosphate, salicylaldehyde, and benzaldehyde did not affect this binding process. Binding of 125I-glycolaldehyde-treated BSA to the cells exhibited a saturation kinetics with an apparent Kd = 3.3 micrograms of the ligand/ml. This binding process was inhibited by unlabeled f-Alb as well as by the antibody raised against the f-Alb receptor. Indeed, 125I-glycolaldehyde-treated BSA underwent a rapid plasma clearance (t1/2 approximately 2 min) which was markedly retarded by unlabeled f-Alb. Upon treatment by these aldehydes, other proteins such as ovalbumin, soybean trypsin inhibitor, and hemoglobin were also converted to active ligands for the f-Alb receptor, while no ligand activity was generated with gamma-globulin and RNase A. These results clearly show that the f-Alb receptor, originally described as being specific for f-Alb, exhibits a broad ligand specificity in terms of both aldehydes and proteins and, hence, should be described as a scavenger receptor for aldehyde-modified proteins.

Acetaldehyde↗
PubMed1986

Acetylated low-density lipoprotein is endocytosed through coated pits by rat peritoneal macrophages.

The surface distribution of the scavenger receptors for acetylated low-density lipoprotein (acetyl-LDL) and their endocytic behavior were studied by the direct immunoperoxidase method using monomeric conjugates of horseradish peroxidase with Fab' antibody raised against LDL. The receptors were demonstrated to be distributed diffusely on the surface membrane of cultured peritoneal macrophages, with preferential localization in coated pit regions. With temperature shift from 4 degrees C to 37 degrees C, acetyl-LDL bound to the surface membrane rapidly disappeared, but became detectable in coated vesicles or lysosomes. Further incubation in the presence of acetyl-LDL revealed lipid vacuoles devoid of a limiting membrane in the cytoplasm, transforming macrophages into typical foam cells. These data suggest that the binding of acetyl-LDL to its receptors triggers the clustering of the receptors into the coated pit regions through which acetyl-LDL is endocytosed by coated vesicles to be degraded in lysosomes with subsequent intracellular accumulation of cholesterol esters.

Animals↗
PubMed1986

Comparative biochemistry of acid proteinase from animal origins.

Acid proteinases from 17 tissues of 12 animal species were compared with respect to molecular weight, inhibition by pepstatin and activation by tripolyphosphate. Gel filtration of acid proteinases from protochordates and vertebrates showed a common elution profile and three peaks with mol. wts of -20,000, -45,000 and above 150,000 were detected with acid-denatured hemoglobin as substrate at pH 3.6. The main component of vertebrate acid proteinases was identified as cathepsin D. In the invertebrate acid proteinases, the elution profiles through gel filtration were characteristic to the tissues examined, and were not so distinct as those of vertebrates. Through a biochemical survey, the animal acid proteinase was discussed from a comparative point of view.

Animals↗