Biomedical subjects

T Akamatsu

Publications and source records attributed to T Akamatsu.

At least 19 recordsLinked to original sources

PubMed1992

Mucin histochemistry of pancreatic duct cell carcinoma, with special reference to organoid differentiation simulating gastric pyloric mucosa.

The present study was undertaken to explore mucins produced in normal, metaplastic, and hyperplastic ductal epithelia as well as in carcinoma tissues of the pancreas, and used a battery of histochemical techniques. Thirty-five cases of ordinary pancreatic duct cell carcinoma and nine cases of duct cell carcinoma, which fulfilled the clinical criteria of "mucin-producing carcinoma of the pancreas," were examined. The results indicated that all lesions of mucinous metaplasia with or without papillary hyperplasia as well as atypical hyperplasia characteristically had gastric mucins and showed organoid differentiation simulating the gastric pyloric mucosa, but never stained for 8-O-acetyl-N-acetylneuraminic acid, which is a histochemical marker of the large intestine. Ordinary duct cell carcinoma also contained gastric mucins and small intestinal mucins and showed organoid differentiation, but rarely had 8-O-acetyl-N-acetylneuraminic acid. Mucin-producing carcinomas were classified into two groups: the ordinary duct cell carcinoma group and a group that showed marked atrophy and extensive fibrosis of the parenchyma, a lack of organoid differentiation and gastric mucins, and an abundance of large and small intestinal mucins. These results suggest that gastrointestinal mucins are useful markers to detect cancer-related lesions and cancers of the pancreas.

Adult↗

PubMed1992

Menopause related changes of adrenocortical steroid production.

To elucidate changes of adrenocortical steroid production with age, reproductive age (n = 14), peri-menopausal (n = 12) and post-menopausal (n = 13) women were studied using basal hormone levels and the results of a rapid ACTH stimulation test. Peripheral serum levels of pregnenolone, 17 alpha-hydroxypregnenolone, 17 alpha-hydroxyprogesterone, dehydroepiandrosterone and androstenedione were measured by RIA. The basal levels of all steroids except pregnenolone decreased with age. A significant increase in the levels of all steroids after ACTH stimulation was observed in all subjects. Although, there was an age related decrease in the response of C19-steroids to ACTH, the response of pregnenolone and 17 alpha-hydroxyprogesterone to ACTH did not alter with age. The preserved response of 17 alpha-hydroxyprogesterone to ACTH in post-menopausal women suggests that 17 alpha-hydroxyprogesterone production plays a role in the age independency of cortisol. In the present paper, the changes in the capacity of the post-menopausal adrenal cortex to produce androgens and C21-steroids were demonstrated.

17-alpha-Hydroxypregnenolone↗

PubMed1992

Al-type generalized amyloidosis showing a solitary duodenal tumor.

An amyloid tumor of the duodenum is a rare occurrence. A patient who presented with epigastric discomfort, in whom a barium meal study revealed a tumor of the duodenum is described. Upper gastrointestinal endoscopy showed a submucosal location of the tumor, and examination of a biopsy revealed amyloid deposition of the AL type. Diffuse tumor involvement of adjacent tissues of the duodenum and also deposits of amyloid fibrils in the liver and skin with no evidence of a chronic pre- existing disease in the patient led to the diagnosis of primary systemic amyloidosis. The distinguishing feature of this case was the formation of a solitary and relatively large tumor in the duodenum mimicking a submucosal tumor, which is in contrast to most reported cases of multiple and smaller amyloid tumors in other parts of the gastrointestinal tract.

Amyloidosis↗

PubMed1992

In vitro closing behavior of the St. Jude Medical heart valve in the pulmonary position. Valve incompetence originating in the prosthesis itself.

We examined the in vitro closing behavior of the St. Jude Medical heart valve, simulating (1) a low-pressure system, (2) the anatomic peculiarity of the right ventricular outflow tract and the main pulmonary artery, and (3) disturbed diastolic compliance of the right ventricle. The variables in the experiment were the load impedance to the pump and the valve orientation. The results were as follows. The sequence of closure of the two semidiscs was based on the valve orientation; reduction in impedance caused the semidisc that closed last to remain open, while the other semidisc continued its open-close motion; further reduction in impedance prevented the semidisc, which continued its open-close motion, from closing completely. These results highlight the forces involved in semidisc closure and the existence of a threshold of force for completion of semidisc closure. Further, the results demonstrate that under certain circumstances the threshold cannot be exceeded via those forces. Therefore this incompetence must originate in the prosthesis itself. In this regard, we suggest an urgent need to reconsider the indications for St. Jude Medical heart valve pulmonic implantation. Finally, we advocate the necessity for an in vitro assessment of valve prostheses in a low-pressure system, to evaluate the safety of right-sided placement.

Evaluation Studies as Topic↗

PubMed1992

[Changes in steroid enzyme activities with age in human ovary].

It is well documented that sex hormone secretion decreases as age advances. In this study, 17 alpha-hydroxylase (17hy), 20 alpha(beta)-hydroxy steroid dehydrogenase (20-HSD), C17-20 lyase, 17 beta-hydroxy steroid dehydrogenase (17 beta-HSD) and aromatase activities in ovarian tissues were examined in order to study the changes in steroid metabolism in human ovary with age. Tissues were obtained from women aged 30-81 years who had undergone gynecological laparotomy. Enzyme activities were measured by the conversion of 14C-labeled progesterone, 17 alpha-hydroxy progesterone and androstenedione to amounts of corresponding labeled products. Remarkable reduction of C17-20 lyase and 17hy activities were noticed in the ovaries obtained from the women in the premenopausal stage when the activities were compared with those from reproduct women. However, the activities of aromatase, 17 beta-HSD and 20-HSD were not changed. Further, a decrease of 17hy activities was observed in the ovaries obtained from menopausal women. Aromatase activity was also reduced at this stage while the 17 beta-HSD and 20-HSD remained unchanged. In addition, the formation of 17 alpha, 20 beta-OH-P4 from 17P4 was first demonstrated indicating that activity of 20 beta-HSD in postmenopausal ovary and found to be localized in the microsomal fraction. These result indicated that the changes of ovarian steroid enzyme activities with age were characterized by a striking reduction in C17-20 lyase and 17hy activities while 17 beta-HSD and 20-HSD activities were not impaired. Aromatase activity was found to be decreased in ovaries at menopause.

17-Hydroxysteroid Dehydrogenases↗

PubMed1991

Adenocarcinoma of the cervical oesophagus arising from ectopic gastric mucosa. The histochemical determination of its origin.

A case of adenocarcinoma of the cervical oesophagus was examined by employing a battery of histochemical techniques and was demonstrated to arise from ectopic gastric mucosa. The patient was a 66-year-old Japanese male. Endoscopy revealed an ulcerated tumour on the right anterior wall of the cervical oesophagus, approximately 16 cm from the incisor teeth. Pathological examination of surgically removed specimens showed well-differentiated tubular adenocarcinoma. Ectopic gastric mucosa was found in the oesophageal mucosa adjoining the carcinoma. Histochemical stains for characterizing mucosubstances and immunostains for various antigens were used. In addition to this carcinoma, ectopic gastric mucosa in the oesophagus and normal oesophageal, cardiac, tracheal and bronchial mucosa were also examined. The results showed that the carcinoma contained mucins, which showed reactivities characteristic of the gastric surface mucous cell (galactose oxidase-cold thionin Schiff reactive) and gland mucous cell (paradoxical concanavalin A staining reactive). Ectopic gastric mucosa consistently contained these mucins, but other tissue sites lacked them.

Adenocarcinoma↗

PubMed1991

Effect of alcohol on blood levels of branched-chain alpha-keto acids in male Wistar rats.

The effect of oral alcohol administration on branched-chain alpha-keto acids was studied in Wistar rats. Rats were divided into alcohol loading groups 1 (ethanol single daily dose: 2.5 g/kg body wt for 14 days) and 2 (ethanol dose: 5 g/kg body wt), and a pair-fed control group (isocaloric glucose and food equal to the amount taken by group 1 the previous day). Branched-chain alpha-keto acids, other alpha-keto acids and amino acids were analysed using high-performance liquid chromatography. Results showed a significant body weight increase in the alcohol loading groups. Concentrations of branched-chain amino acids and keto acids were significantly increased in the alcohol-treated groups. The blood levels of methionine, threonine, alanine and glutamic acid were also increased by alcohol administration. Blood levels of taurine and ornithine, however, showed a significant decrease in the alcohol-treated groups. These results show that alcohol increases the blood levels of branched-chain keto acids and branched-chain amino acids.

Alcohol Drinking↗

PubMed1991

[Relations of serum apolipoprotein A-I, A-II and B levels to smoking, drinking and body mass].

To examine whether the serum apolipoprotein A-I level (Apo A-I), serum apolipoprotein A-II level (Apo A-II) and serum apolipoprotein B level (Apo B) are related to cigarette-smoking habits, drinking frequency and body mass index (BMI) independent of serum lipoprotein cholesterol levels (HDLC, LDLC or VLDLC), we statistically analyzed the data on Apo A-I, Apo A-II, Apo B, HDLC, LDLC and VLDLC and the life style data obtained from health examinations of 256 male residents aged 40 to 49 mostly randomly selected from two Japanese areas, Ninohe, Iwate and Ishikawa, Okinawa. The results were as follows: (1) HDLC was strongly positively correlated with Apo A-I and Apo A-II, while Apo B was strongly correlated with LDLC and VLDLC. (2) According to univariate analyses, Apo A-I, Apo A-II, Apo B, HDLC, LDLC and VLDLC were not associated with smoking. On the other hand, drinking frequency was positively associated with Apo A-I, Apo A-II and HDLC. Apo A-I and HDLC were negatively correlated with BMI, whereas Apo B, LDLC and VLDLC were positively correlated with BMI. (3) According to the results of multi-dimensional analyses of covariance, Apo A-II was positively correlated with drinking frequency independent of Apo A-I and HDLC, especially among the individuals with increased HDLC. The same multivariate analysis showed that Apo B was positively associated with smoking independent of LDLC and VLDLC among the individuals without increased VLDLC. From these results, we conclude that Apo A-II may be effective as a biological marker for alcohol drinking independent of Apo A-I and HDLC, while cigarette smoking may affect Apo B through a certain direct mechanical effect. (4) Increased HDLC in obese individuals (BMI greater than or equal to 27) or non-drinkers was associated with remarkably increased Apo A-I, while decreased HDLC in thin individuals (BMI less than 21) was associated with remarkably decreased Apo A-II.

Adult↗

PubMed1991

Epidemiology of glaucoma in Japan--a nationwide glaucoma survey.

A population-based, collaborative glaucoma survey was conducted in seven regions throughout Japan, during the years of 1988 and 1989. The total number of subjects examined was 8,126 out of 16,078 residents aged 40 years or older, representing a participation rate of 50.54%. There were no significant differences in background factors between participants and randomly sampled nonparticipants. A mainstay of the screening consisted of tonometry and fundus photography with nonmydriatic camera, followed by automatic perimetry as a recall examination. Overall prevalences obtained were primary open-angle glaucoma (POAG) 0.58%, low-tension glaucoma (LTG) 2.04%, primary angle closure glaucoma (PACG) 0.34%, other types of glaucomas 0.60%, and ocular hypertension (OH) 1.37% at the time of screening. The very high prevalence of LTG and extremely low prevalence of OH in the Japanese might reflect a racial peculiarity in the age-specific trend of the intraocular pressure. The prevalence of PACG was found much higher in Japanese than in Caucasians, with a predilection for women. Racial peculiarities as revealed in this study were discussed, with particular reference to the refractive status in the Japanese that showed progressive decrease in myopia with age.

Adult↗

PubMed1991

Factors affecting the patency of stents in malignant biliary obstructive disease: univariate and multivariate analysis.

To investigate the factors affecting the patency of biliary stents, we performed univariate and multivariate analyses in 370 straight stents with diameters of 10- to 12-French gauge which had been inserted singly as palliative treatment in 228 patients with malignant biliary obstructive disease. In the analysis of 226 first stents, advanced age of patients and higher serum bilirubin levels before insertion were found to be significant unfavorable factors limiting the duration of stent function. Overall, older age, male sex, no stent cleaning, and insertion on three or more occasions were significant unfavorable prognostic factors for patency. The risk of occlusion for stents inserted on three or more occasions was 2.32 times that of the first stent insertion. The median duration of patency of first, second, and subsequent stents was 177, 98, and 97 days, respectively. Diagnosis and the area of stenosis were unrelated to patency. No predictive significance of length or size of stent between 10- and 12-French gauge was found in our study.

Actuarial Analysis↗

PubMed1990

Histochemical demonstration of mucins in the intramucosal laminated structure of human gastric signet ring cell carcinoma and its relation to submucosal invasion.

Thirty-one cases of signet ring cell carcinoma of the human stomach at an early stage were studied, employing a variety of histochemical techniques to characterize mucins and to elucidate factors accelerating the invasion of carcinoma beyond the muscularis mucosae. Signet ring cells were classified into six types largely depending on their histochemical reactivities. In 29 of 31 cases examined, the histochemical stainings detected the presence of characteristic mucins in an intramucosal laminated structure of proliferating carcinoma cells. The upper and lower layers of the typical intramucosal laminated structure consisted of carcinoma cells containing surface mucous cell and glandular epithelial cell-type mucins respectively, whereas the middle layer was occupied by immature carcinoma cells. Such a structure appeared to simulate cellular differentiations occurring in normal mucosa. The intramucosal laminated structure underwent structural distortion or disappeared, where submucosal invasion was evident. Ulceration appears to trigger the invasion beyond the muscularis mucosae.

Adenocarcinoma, Mucinous↗

PubMed1990

A case of multiple cavernous hemangioma of the small intestine and clinical review of the Japanese literature.

We report a case of multiple cavernous hemangioma of the small intestine which was diagnosed definitively before operation. A 33-yr-old male was found to have multiple polypoid lesions in the small intestine during examination for recurrent iron deficiency anemia. Plain X-ray film of the abdomen revealed multiple calcifications in the middle to lower region, suggestive of cavernous hemangioma, which was further confirmed by angiography and scintigraphy with Tc 99m-labeled red blood cells. Endoscopy during surgery was used to determine the extent of surgical resection. Seventy-three cases of hemangioma of the small intestine were reported in Japan between 1953 and 1988 and their clinical features were reviewed.

Adult↗

PubMed1990

Nucleotide sequences of the Bacillus subtilis flaD locus and a B. licheniformis homologue affecting the autolysin level and flagellation.

A DNA fragment containing the flaD locus of Bacillus subtilis, which had been cloned into plasmid pAC3, was subcloned into an M13 phage and sequenced. The sequence contained five open reading frames (ORFs), of which ORF2 was the flaD gene. Unexpectedly, the sequence of the flaD locus was identical to that of sin [sporulation inhibition gene; Gaur, N. K., Dubnau, E. & Smith, I. (1986). Journal of Bacteriology 168, 860-869]. A B. licheniformis homologue (flaL) of the B. subtilis flaD locus was cloned into pUC19 and identified by colony hybridization. The B. licheniformis DNA was subcloned and sequenced. Two ORFs (ORF1, or L-ORF1; and ORF2, or flaL) were detected, encoding 58 and 111 amino acid residues, respectively. These are almost identical in length to ORF1 (D-ORF1; 57 amino acids) and flaD (111 amino acids) on the fragment of B. subtilis DNA. The overall interspecies differences between the nucleotide sequences of D-ORF1 and L-ORF1, and those of flaD and flaL, were 42% and 11%, respectively, and the differences in the predicted amino acid sequences were 50% and 7%, respectively. The regions 3' of the ORFs (flaL and flaD) in both species resemble rho-independent terminators of transcription. The characteristics of the amino acid sequences are also discussed.

Amino Acid Sequence↗

PubMed1990

[Efficacy of acellular pertussis vaccine].

An outbreak of pertussis occurred in one room of a residential facility where 19 children aged 5 to 36 months were residing. They were prospectively surveyed to estimate the efficacy of acellular pertussis vaccine. Among the 19 residents, 9 were immunized with acellular pertussis vaccine. Among the 19 residents, 9 were immunized with acellular DTP vaccine and 10 were unimmunized. The spread of pertussis was surveyed bacteriologically and serologically for 2 months. Among the 9 immunized, 7 children acquired the laboratory-confirmed pertussis and 1 of the 7 developed the typical symptoms (whooping or paroxysmal coughing attack lasting for 14 days or more). Among the 10 unimmunized, 7 children acquired the laboratory-confirmed pertussis and 6 of the 7 developed the typical symptoms. There was no difference in the rate of secondary infection (7/9:7/10), but there was a significant difference in the rate of development of the typical symptoms (1/7:6/7 p less than 0.05). The point estimate of protective efficacy of the acellular DTP vaccine against typical pertussis was (6/10 - 1/9)/(6/10) x 100 = 81%. It was concluded from these findings that acellular DTP vaccine could not prevent the infection of Bordetella pertussis, but could prevent the development of the typical symptoms.

Child, Preschool↗

PubMed1990

[Trichloroethylene concentration in the work environment in relation to the development of pneumatosis cystoides intestinalis].

Four cases of primary pneumatosis cystoides intestinalis (PCI) were studied in relation to occupational trichloroethylene (TRI) exposure. Three of the patients were exposed to TRI in the process of washing or polishing of camera lenses. The maximum concentration of TRI in the work environment of two PCI patients often exceeded 50 ppm, though the geometric mean concentrations were below this value. Monitoring of TRI exposure by measuring urinary TRI metabolites suggested that the third patient had been working in the environment with an 8-h time weighted average TRI concentration exceeding 50 ppm. Scrutiny of 19 PCI cases thus far collected by us revealed that i) three groups of patients (7 in total) were working in the same factories, ii) most of the PCI patients were workers in small-scale factories having poor working conditions, and iii) occupational TRI exposure is probably responsible for the development of primary PCI.

Adult↗

PubMed1990

The role of preventive medicine in developing countries.

In trying to demonstrate the importance of preventive medicine in health care promotion, previous studies involving prevention and control of diseases have been discussed. Preventive medicine is also urged as the best method to help promoting health especially in the developing countries. Developed countries are urged to support developing countries, materially and financially in promoting their health. In terms of cost analysis prevention is an investment in health that produce a reduced probability of mortality and/or morbidity, therefore, we, investors in the developing countries, have to sacrifice something today in order to gain a benefit at a later point in time.

Communicable Disease Control↗

PubMed1990

Present health situation in Tanzania.

This article discusses the present health situation in Tanzania, however, health system before independence, the colonial health system, has been the foundation on which the present health services in Tanzania are built upon. The population growth in Tanzania is high (3.2% in 1986), and projected to be 3.7% by the year 2,000. This high growth explains why it is difficult to achieve health objectives on the long term basis. Compounded to this is the economical crisis in the country. Child population in Tanzania account for about 47% of the total population in 1986. Maternal and Child Health Care services (MCHC) are discussed, with much emphasis on the child health care problems, and different programmes involved in improving child health care in the country. Problems of poor environmental sanitation are discussed including possible solutions for Tanzania. Tanzania, in this article, is urged to strengthen the existing health services in terms of staff, drugs, other supplies and equipment in order to give adequate health care to its people. Tanzania should also balance the distribution of resources between urban and rural so as to comply with the objective of the national health policy of comprehensive basic health services equitably to all within the limited available resources and to be able to reach the ultimate goal of health for all the people in the country by the year 2,000.

Child↗

PubMed1989

Availability of immunostaining methods for identification of mixed-up tissue specimens.

The immunostaining method of ABO blood determinants in tissue sections is useful when surgical tissue specimens, submitted for diagnosis, are improperly identified. This article reports two cases in which the surgical specimens became mixed-up and the ABO immunostaining method was used to identify the patients' tissues correctly and prevent unnecessary surgery.

Biopsy↗