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Biomedical subjects

Y Yoshikawa

Publications and source records attributed to Y Yoshikawa.

At least 217 records · Page 12Linked to original sources
PubMed1995

Analysis of sexual behavior in rams (Ovis aries).

In this study, a matured ram was paired with an estrus ewe and sexual behavior was investigated. All the behavior was recorded by a time-lapse video tape recorder from the start of pairing. The series of unit movements comprising the sexual behavior, the mounting series (MS), was extracted from the record and analyzed quantitatively (n = 774). The MS starts from ram's approaching or following a ewe and ends by ram's mounting on a ewe. The sexual behavior was consisted of the following eight unit movements, following or approaching (F/A), chin resting (CR), flehmen (Fl), mounting (Mo), nosing (No), nudging (Nu), pushing (Pu) and twisting (Tw). Analysis of a frequency of any combinations of two unit movements consisted of preceding and succeeding ones, observed in the MS was conducted by cell-by-cell test using the transitional matrix to make a flow-diagram of the ram's sexual behavior. As a result, the pattern of unit movements, F/A-Tw-Nu-CR-Mo, formed a main route of the MS, whereas the repertoire of a sequential pattern increased by diverging. Though Fl and No didn't lead to mounting directly, these movements associated with olfactory perception also belonged to sexual behavior and may have independent function from other six unit movements that constitute the MS.

Animals↗
PubMed1995

[Histopathological studies on senile plaques and cerebral amyloid angiopathy in aged cynomolgus monkeys].

The incidence and morphological characteristics of senile plaque and amyloid angiopathy in the cerebrum of six aged cynomolgus monkeys (Macaca fascicularis), 20 to 29 years old, were studied histopathologically and immunohistochemically. By periodic acid methenamine silver stain (PAM) and alkaline Congo red stain, senile plaques were detected in 5 out of 6 cases, and 3 of them were positive for amyloid in the wall of capillaries and arterioles in the cerebral cortex. Senile plaques were classified into three types. Mature plaques, including classical and primitive types, were more frequently observed than the immature diffuse type. Senile plaques were often seen in the cortex of temporal lobe, putamen and head of caudate nucleus. Since mature types of senile plaques were seen frequently around vascular amyloid deposition and no amyloid angiopathy was detected in the areas without senile plaques, the close relation between senile plaque of the mature type and amyloid angiopathy might be considered. All senile plaques and amyloid angiopathy were positively stained immunohistochemically with antibody against amyloid beta-protein (A beta P) 1-40 synthetic peptide, but all diffuse and some primitive plaques were negative for antibody against A beta P 8-17 synthetic peptide. Neither senile plaque nor amyloid angiopathy was detected in the cerebrum of 15 young monkeys, 9 to 11 years old, examined as controls.

Aging↗
PubMed1995

[Clinical studies on 14 cases of adult-onset Still's disease].

We here report fourteen patients diagnosed as adult-onset Still's disease (AOSD) in our hospital. Seven patients were males (mean age at onset was 26.6 years), and seven were females (30.6 years). All of the cases had spiking fever ( > 39 degrees C) and joint symptoms. Hepatomegaly, splenomegaly, and lymphadenopathy were noted in 50% of the patients, respectively. Skin eruption was seen in twelve patients (85.7%). Among them, nine patients (64.3%) exhibited typical rash. Pleuritis or pericarditis was seen in one case each. Only one patient revealed neurological disorder. Abdominal pain was present in 50% of the cases. The ratio of occurrence of secondary amyloidosis was 14.3%. Four patients (28.6%) were diagnosed to have the apophyseal narrowing at the cervical spine (C2-C3). Two patients (14.3%) accompanied by Sjögren's syndrome were women over 40 years of age. The levels of soluble interleukin-2 receptor were significantly elevated in the sera obtained from seven patients with AOSD and four patients with juvenile-onset Still's disease, compared with normal controls. It seems to support the notion that immunopathologic processes via T cell activation play an important role in the pathogenesis of AOSD.

Adolescent↗
PubMed1995

Significance of laparoscopic excisional biopsy for polypoid lesions of the gallbladder.

Polypoid lesions of the gallbladder taken from 103 patients were examined to correlate clinical indicators with pathological characteristics. By ultrasonographic examination, no carcinoma was found in polypoid lesions with a diameter less than 1 cm. However, the incidence of carcinoma in those with diameters greater than 1 cm was 23%, a lower rate than expected from previous pathological studies. Comparison of ultrasonographic and actual measurements suggested that the size of cholesterol polyps tended to be overestimated by ultrasonography, suggesting that the apparent risk of cancer was decreased by cholesterol polyps. Laparoscopic cholecystectomy was performed in 30 patients with polyps. No complications were encountered, and operative time was significantly shorter (p < 0.01) than in the 116 laparoscopic cholecystectomies for cholelithiasis. This study demonstrated the difficulty in distinguishing large benign polyps from carcinoma by ultrasonography. To complete the diagnosis with less invasive intervention, we propose the use of laparoscopic cholecystectomy for patients with polypoid lesions larger than 1 cm by ultrasonographic estimation.

Adenocarcinoma↗
PubMed1995

Urodynamic study of storage and evacuation of urine in patients with a urethral Kock pouch.

PURPOSE: The urodynamics of pouch-urethra function were investigated in patients with a urethral Kock pouch to understand mechanisms involved in the storage and evacuation of urine, and elucidate any problems of long-term outcome. MATERIALS AND METHODS: Urodynamic evaluation was performed in 18 male patients who underwent bladder replacement with a urethral Kock pouch following radical cystectomy. RESULTS: Good urinary continence was achieved with normal frequency of voiding. On urodynamics pressure within the pouch remained low during the storage phase (mean 33.2 cm. water) but markedly increased during the evacuation of urine (mean 77.3 cm. water). In 8 patients (44%) extremely high pressure within the pouch (80 to 150 cm. water) was noted at voiding. Clean intermittent self-catheterization was initiated in a patient with high pressure within the pouch at voiding in whom pouch-ureter reflux developed 7 months postoperatively. The external urethral sphincter was impaired to some extent postoperatively but it contracted in response to filling of the pouch with a marked increase in urethral pressure from a mean of 31.6 to 66.3 cm. water. CONCLUSIONS: Urodynamic and radiological studies will be necessary periodically since high pressure within the pouch at voiding might jeopardize the antireflux mechanism, leading to reflux and renal impairment.

Adult↗
PubMed1995

[Amyloidosis of the small intestine secondary to rheumatoid arthritis and juvenile rheumatoid arthritis: report of two cases].

We herein report two cases of gastrointestinal amyloidosis, secondary to juvenile rheumatoid arthritis (JRA) in one, and rheumatoid arthritis (RA) in the other. A 21-year-old woman, who has been suffering from JRA for the past 12 years, was transferred to our hospital due to intense pain in the epigastrium and back, diarrhea, high fever, and paralytic ileus. Treatment by corticosteroid, antibiotics, protease inhibitor, and total parenteral nutrition was not effective. The laparoscopic surgery was performed because of repeated melena followed by an episode of hypovolemic shock. The resected specimen of the ileum showed histologically marked amyloid deposition in the arteriolar walls. A 83-year-old man with RA for 14 years, was admitted to our hospital with complaints of abdominal pain, nausea, and diarrhea. He underwent an emergency operation for perforation of the ileum. The resected specimen revealed amyloid deposition and non-caseating granulomas. The fragility and impaired blood supply caused by amyloid deposition in the vascular walls may have terminated in the severe intestinal lesion. Further clinicopathological studies along this line are keenly desired in order to establish therapeutic modalities for gastrointestinal amyloidosis.

Adult↗
PubMed1995

Effect of a lipid-lowering agent or a high-cholesterol diet on focal glomerulosclerosis in hyperlipidemic rats.

Hyperlipidemic rats given a diet supplemented with 1% probucol (4,4'-isopropylidenedithiobis [2,6-di-tert-butylphenol]) or 4% cholesterol with 1% cholic acid from 4 to 20 weeks of age were evaluated for the effect of a lipid-lowering agent or a high-cholesterol diet on focal glomerulosclerosis. Although mean cholesterol and phospholipid concentrations in hyperlipidemic rats given probucol were lower than those in control hyperlipidemic rats, there was no difference in urinary protein content or renal histologic findings when the two groups were compared. Mean cholesterol, phospholipid, urea nitrogen, and creatinine concentrations in hyperlipidemic rats given a high-cholesterol diet were greater than those in hyperlipidemic rats given a normal diet, and the glomerular sclerotic lesions became more severe.

Animals↗
PubMed1995

Daunomycin induces elongation for a compacted single DNA molecule.

Effect of daunomycin on the higher order structure of single giant DNA molecule compacted by spermidine was studied using fluorescence and electron microscopies. We found that, with the addition of daunomycin, unfolding of the compacted DNA is induced, indicating that this drug has the activity to loose the higher order structure of the compacted state. Such an effect will be concerned with the antitumor activity of daunomycin.

Antibiotics, Antineoplastic↗
PubMed1994

Percutaneous transluminal coronary angioplasty of the left internal thoracic artery graft: a case report in a child.

A 9-year-old girl who had undergone previous coronary artery bypass surgery at the age of 3.5 years for stenoses of the left anterior descending and right coronary arteries resulting from Kawasaki disease presented with recurrent exertional angina. Stenosis was found at the anastomosis of the left internal thoracic artery to the left anterior descending artery. Percutaneous transluminal coronary angioplasty was successfully performed. This is the first reported case of percutaneous transluminal coronary angioplasty of an internal thoracic artery graft in a child.

Angioplasty, Balloon, Coronary↗
PubMed1994

Pelvic fascia strength in women with stress urinary incontinence in comparison with those who are continent.

Biophysical properties of the anterior vaginal wall as well as the rectus fascia were evaluated in vivo by penetrating the Stamey needle into these tissues of 26 female patients with stress incontinence in comparison with those of 21 continent subjects. The results demonstrated that shear strength of the anterior vaginal wall was lower in incontinent patients than in continent subjects (P < 0.01). Shear strength of the rectus fascia in the patients, which was not supposed to be related to urinary incontinence and should have had the same strength as the control subjects, was also found to be lower than the control (P < 0.01). Shear strength of the vaginal wall was not correlated with age irrespective of their continence status (P > 0.05). Based on our findings it is concluded that some women suffering from stress incontinence may have a hereditary disorder of biophysical properties of the tissues.

Adult↗
PubMed1994

Pathology of equine pneumonia associated with transport and isolation of Streptococcus equi subsp. zooepidemicus.

Seven horses that died of pneumonia associated with transport yielded Streptococcus equi subsp. zooepidemicus (S.z.) from their pulmonary lesions. These lesions were divisible roughly into two types, serous haemorrhagic pneumonia and multiple foci of coagulative necrosis, which were considered to reflect a temporal difference in the process of lesion formation. Immunohistologically, S.z. antigen was detected in both types of lesion. Acute necrotic lacunar tonsillitis was considered to play an important role in the onset of the pneumonia.

Animals↗
PubMed1994

Cryopreservation of spermatozoa from cynomolgus monkeys (Macaca fascicularis).

Fertilization of eggs from cynomolgus monkeys (Macaca fascicularis) was achieved in vitro using frozen-thawed spermatozoa. The best sperm survival rate was obtained after freezing spermatozoa in a semen-diluting medium (TTE: Tes, Tris, egg yolk base) containing 5% glycerol with 30 min equilibrium time. Although frozen-thawed spermatozoa could fertilize eggs in vitro and some of the fertilized eggs developed into blastocysts or hatched blastocysts, a sperm fertility assay using salt-stored eggs indicated that frozen-thawed spermatozoa had a shorter lifespan in capacitation medium than did fresh, unfrozen spermatozoa. This may be attributable to damage to their plasma membranes.

Animals↗
PubMed1994

[A feeding experiment on laboratory-bred male cynomolgus monkeys. I. Morphometrical study].

Effects of restricted feeding on the growth of laboratory-bred male cynomolgus monkeys (Macaca fascicularis) aged between one year and four years were studied morphometrically. A series of 11 variables representing physical elements were measured. Before 2.5 years of age, the amount of commercial diet (Type AS, 382kcal/100g and 28.1% of crude protein, Oriental Yeast Co. Ltd.) per day was restricted to 50g (group A), 30g (group B) or 20g (group C) and increased to 100g (group A), 50g (group B) or 40g (group C) respectively at 2.5 years old. Throughout the experimental period ca 100g of apples and oranges per day were provided. Significant differences in body weight between group A and C were detected excepting the early period of the experiment. Although the slight suppression in weight gain was observed in group B during the second trimester of the experiment, body weight increased gradually after increasing the amount of food and no significant difference from A was observed at four years of age. The minimum requirement of diets is judged to be 30g/day before two years old and 50g/day over two years old in the laboratory-bred male cynomolgus monkey. Moreover, the suppressive effects of restricted feeding were most significant on the growth of the limbs and, secondarily, on the growth of the trunk. Practically no effect on the growth of the head was observed.

Animal Feed↗
PubMed1994

[Feeding experiment on laboratory-bred male cynomolgus monkeys. II. Hematological and serum biochemical studies].

The effects of restricted feeding on hematological and serum biochemical values were studied in laboratory-bred male cynomolgus monkeys (Macaca fascicularis) aged between one year and four years. In animals younger than 2.5 years old, the amount of commercial diet (Type AS, Oriental Yeast Co. Ltd.) given per day was restricted to 50 g (group A), 30 g (group B) or 20 g (group C) and increased to 100 g (group A), 50 g (group B) or 40 g (group C) at 2.5 years old. Throughout the experimental period, about 100 g per day of apples and oranges were fed to the animals. Differences in red blood cell counts, hematocrit values and hemoglobin concentrations between groups A and C were detected in the middle period of the experiment. The function of hematogenesis may be suppressed by restricted feeding. A significant increase in serum triglyceride concentration in group C and slight increase in group B were observed during the second trimester of the experiment. A decrease in serum alkaline phosphatase activities in group C during the same period suggests that restricted feeding has a suppressive effect on bone growth. The results obtained by hematological and serum biochemical observations in this study are in good agreement with the previous somatometric study [10].

Alkaline Phosphatase↗
PubMed1994

[Age-related changes in bone mineral density, mean width and area of the lumbar vertebrae in male African green monkeys (Cercopithecus aethiops)].

We were able to measure bone mineral density (BMD), mean bone width and the area of the lumbar vertebrae in male African green monkeys with a dual-energy X-ray absorptiometry (DPX-alpha, Lunar, USA). For analysis of spinal bone mass, mean width and area of the bone, we scanned lumbar vertebrae L3-L5 using a pediatric analysis program. We used restraining bed made of formed polystyrol to support the animal in a supine position. The precision of the measuring technique was calculated by averaging the coefficients of variance of the 5 scans obtained in 5 animals aged from 5 to 7 years. The precision values for BMD, bone width and area were 1.9%, 0.9% and 2.6%, respectively. Furthermore, age-related changes in bone measurements were demonstrated using laboratory-bred males (n = 45) and, additionally, wild-originated males (n = 7, estimated ages over 15 years old). The values of B M D, bone width and area at 6 months old were about 0.3 g/cm2, 1.2cm and 4.5 cm2 respectively. These values increased with aging to about 0.7 g/cm2, 1.5 cm and 11cm2 at 5 years old, respectively, and were judged to reach plateau. However, animals over 10 years old and wild-originated animals which had been kept over 10 years in our breeding colony showed rather smaller BMD and area values than the animals aged 5 to 10 years. The animals aged between 5 and 10 years seemed to have retained a peak bone mass in this primate species.

Absorptiometry, Photon↗
PubMed1994

[Measuring bone mineral content and soft tissue mass in living the cynomolgus monkey].

Bone mineral content and soft tissue (lean and fat) mass in living female cynomolgus monkeys were successfully measured with a dual-energy X-ray absorptiometry (DEXA; DPX-alpha, LUNARE, USA). Measurements were performed using a restraining bed made of forming polystyrol with 5cm thickness to support the animal in a supine position. Accuracy of measurements was checked by using a dummy consisted by various combinations of lean, lard and ribs. The results confirmed that this system is able to measure each constituent exactly. The percentage of fat in the soft tissue is seemed to be better index of obesity in this primate species when compared with other obesity markers such as body weight and morphometry.

Absorptiometry, Photon↗