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Biomedical subjects

H Miyazawa

Publications and source records attributed to H Miyazawa.

At least 91 records · Page 5Linked to original sources
PubMed1993

Periventricular hyperintensity on magnetic resonance imaging correlated with brain ageing and atrophy.

Fifty-two patients with cerebrovascular risk factors without neurological abnormalities were reviewed with respect to periventricular hyperintensity (PVH) on T2-weighted magnetic resonance imaging (MRI); brain atrophy was also assessed by CT and T1-weighted MRI. Extensive PVH showed a stronger correlation with age-related atrophy than mild or absent PVH. The relative volume of brain affected by PVH, calculated by computer, also correlated with brain atrophy, especially ventricular enlargement. The effects of PVH on brain ageing and atrophy is discussed.

Aged↗
PubMed1993

Airborne cat (Fel d I), dog (Can f I), and mite (Der I and Der II) allergen levels in the homes of Japan.

We measured the airborne and floor dust allergen levels of the cat (Fel d I), dog (Can f I), and mite (Der I and Der II) allergens in 13 houses. Airborne allergens were sampled with a low-noise air sampler for 5 to 7 days in the living rooms where the inhabitants were living as usual. The mean levels of airborne Fel d I and Can f I in houses with cats or dogs were 5960 and 2880 pg/m3, respectively, which were about 160 and 100 times higher than levels of airborne Der I. In floor dust the mean levels of Fel d I and Can f I were 322 and 236 micrograms/gm fine dust, respectively, which were 59 and 10 times higher than the levels of Der I. These results suggest that the airborne cat and dog allergens might be important sources of allergens for persons who live in a house with those animals, because the absolute allergen levels in both the air and dust are significantly higher than those of mite.

Air↗
PubMed1993

Determination of 18F-fluoro-2-deoxy-D-glucose rate constants in the anesthetized baboon brain with dynamic positron tomography.

We have determined the rate constants (ki*) of 18F-fluorodeoxyglucose (FDG) in the unlesioned baboon brain, for use in positron emission tomography (PET) measurements of glucose utilization. In contrast to earlier reports, we used a radiosynthesis which guarantees production of FDG essentially uncontaminated by fluorodeoxymannose, and an improved determination of ki* by (1) direct measurement of the time-shift between bolus arrival in femoral arterial plasma and brain, (2) rapid initial PET frames, and (3) extended data acquisition (up to 180 min). Young adult baboons were studied under anesthesia with either phencyclidine or etomidate. The FDG time-activity curves obtained from temporal grey matter showed a consistent decline after about 80 min, indicating true product loss. Three-compartment modelling was performed for increasing fitting intervals (20-120 min) with both a 5-parameter (K1*-k4*, and vascular volume (Vo)) and a 4-parameter (K1*-k3*,Vo) model. With the latter, both the calculated FDG net clearance ((K* = K1*.k3*/(k2* + k3*)) and the fitted kinetic constants were dependent on fitting interval, i.e., they showed sustained unstability. With the former, the constant k4*, which presumably represents dephosphorylation, was overestimated and unstable for short fitting times (presumably due to heterogeneous brain compartments in the sample tissue), but stabilized at approximately 0.01 min-1 for fitting times > or = 80 min; K1*-k3* and K* were also stable after this time. These findings were identical for both anesthetic regimen. Thus, in the anesthetized baboon, the FDG ki* values can be reliably determined based on an adequate PET acquisition paradigm and with a model that incorporates k4* and > or = 80 min time-activity data.

Anesthesia↗
PubMed1993

MEN type 1 associated with mediastinal carcinoid producing parathyroid hormone, calcitonin and chorionic gonadotropin.

A 34-year-old Japanese woman was admitted to our hospital with a mediastinal tumor. Laboratory data showed high levels of calcitonin (CT), human chorionic gonadotropin (hCG) and parathyroid hormone (PTH) in the serum. Surgery was performed, but the tumor could not be completely resected. The patient died in the 10th postoperative month due to systemic metastasis and cachexia. At autopsy, diffuse parathyroid hyperplasia and multiple islet cell tumors of the pancreas were found. A pathological diagnosis of multiple endocrine neoplasia (MEN) type 1 associated with mediastinal atypical carcinoid tumor was made. Immunohistochemical study indicated the tumor cells of the mediastinum to be positively stained for hCG beta but not for PTH or CT. The tumor tissue contained significantly high levels of CT, PTH and whole hCG. This is the first case report on MEN type 1 associated with mediastinal carcinoid tumor producing PTH, CT and hCG beta.

Adenoma, Islet Cell↗
PubMed1993

Site-specific initiation of DNA replication in metazoan chromosomes and the role of nuclear organization.

We have asked whether or not Xenopus eggs or egg extracts, which have previously been shown to replicate essentially any DNA molecule, will preferentially utilize a known mammalian OBR. Our results reveal that Xenopus egg extracts can preferentially initiate DNA replication at sites chosen in vivo by the hamster cell, provided that the DNA substrate is presented to the extract in the form of a nucleus rather than bare DNA. Thus, site-specific initiation of DNA replication in metazoan cell chromosomes appears to be determined by nuclear organization as well as DNA sequence. We have also considered whether or not BPV, which was previously reported to regulate its copy number through negative as well as positive cis-acting sequences, provides a suitable paradigm for cellular origins. The BPV genome was found to contain cis-acting sequences that can suppress DNA replication driven by a lytic virus such as PyV. However, this suppression did not require any BPV protein, did not limit PyV origin activity to one initiation event per S phase, and did not affect BPV origin activity. These results, together with data from other laboratories, strongly suggest that BPV is simply a slow-replicating version of SV40 and PyV and therefore is not an appropriate model to explain how initiation of cellular DNA replication is limited to once per cell cycle.

Animals↗
PubMed1993

[Effect of storage conditions on the infectivity of Chlamydia pneumonia].

In order to facilitate the isolation of C. pneumoniae, strain similar TWAR, with high frequency, we investigated the effect of various factors on the infectivity of Chlamydia using two laboratory strains, C. pneumoniae TWAR and C. trachomatis serovar D. The factors tested were the effects of different temperatures for storage conditions, saliva from healthy person, storage media for Chlamydia, and the frequency of freezing and thawing. Chlamydial suspension was prepared in the two media, SPG (sucrose-phosphate-glutamate buffer pH 7.5), and CT-GM (culture medium for Chlamydia which contains 1 micrograms/ml cycloheximide and 0.04% glucose). Chlamydial suspension was allowed to stand in each of four different thermal conditions: 37 degrees C, room temperature (25 degrees C), 4 degrees C, 0 degrees C and -75 degrees C for 1, 3, 6, 24, 48, 72, 96, 120 and 144 hours. For storage at -75 degrees C, one of three groups of glass vial tubes containing Chlamydia was covered with an "airmat" to prevent the rapid freezing of Chlamydia. The effect of various factors on the infectivity was assayed by inoculation of the suspension on HeLa 229 cell monolayers. Results showed that the infectivity rapidly decreased at 37 degrees C and room temperature, while at 4 degrees C, 0 degrees C and -75 degrees C, relatively high infectivity was maintained and contained until days 4 to 6. This decreasing pattern was similar to among the media used. We were not able to find any differences in the infectivity among the samples with or without the "airmat".(ABSTRACT TRUNCATED AT 250 WORDS)

Chlamydia↗
PubMed1993

In vivo mapping of brain benzodiazepine receptor changes by positron emission tomography after focal ischemia in the anesthetized baboon.

BACKGROUND AND PURPOSE: Recent reports have shown an increase in specific binding (in vitro) of [3H]PK 11195 to peripheral-type benzodiazepine receptors in both experimental animals and humans, reflecting a glial/macrophagic reaction within and around focal ischemic insults. We have evaluated by positron emission tomography the time course of changes in brain uptake in vivo of 11C-labeled PK 11195 and flumazenil (an antagonist of central benzodiazepine receptors) as indirect and direct markers of neuronal loss, respectively, after focal cerebral ischemia. METHODS: Ten anesthetized baboons were submitted to sequential positron emission tomography studies between day 1 and day 91 after unilateral middle cerebral artery occlusion. The studies consisted of successive assessments, in the same positron emission tomography session, of [11C]PK 11195, [11C]flumazenil, cerebral blood flow, and oxygen consumption; late computed tomographic scans were obtained to map the approximate contours of infarction and to define a concentric peri-infarct area. RESULTS: We found a significant time-dependent increase in [11C]PK 11195 uptake in the peri-infarcted area, maximum at 20 to 40 days after occlusion. In contrast, there was a time- and perfusion-independent significant decrease in [11C]flumazenil uptake in the infarcted area, stable from day 2 onward, and already present in one baboon at day 1. Challenge studies with saturating doses of cold ligands confirmed that these changes represented alterations in specific binding. [11C]Flumazenil uptake was not affected in hypometabolic (but apparently noninfarcted, ie, deafferented) cortical areas. CONCLUSIONS: The delayed and apparently transient increases in [11C]PK 11195 specific uptake in vivo presumably represent glial/macrophage reaction; the marked depression in [11C]flumazenil specific binding, which appears selective for synaptic damage, is both precocious and sustained and thus may be better suited for the early assessment of ischemic damage in humans.

Animals↗
PubMed1993

PET imaging of non-small-cell lung carcinoma with carbon-11-methionine: relationship between radioactivity uptake and flow-cytometric parameters.

Carbon-11-methionine PET scans were obtained from 24 patients with non-small-cell lung carcinoma for whom surgical treatment was considered. The tumor mass was visualized with clear delineation. After PET scanning, the tumor was removed by lobectomy or pulmonectomy. The tumor tissue was first processed to yield tumor cell suspensions and then subjected to DNA flow cytometry. Comparison between 11C uptake rate and flow-cytometric data gave the following results: 11C uptake rate in the tumor correlated well with the cellular DNA content (DNA index) of tumor cells at the resting state of cell division (G0 + G1-phase) (r = 0.67). The correlation between 11C uptake rate and S-phase cell percentage was markedly high (r = 0.76), and the correlation between 11C uptake rate and S+G2/M-phase cell percentage was extremely high (r = 0.86). It was concluded that the tumor uptake rate of 11C-methionine was representative of tumor growth rate in this tumor type.

Aged↗
PubMed1993

[The background of foreign patients with pulmonary tuberculosis and investigation of treatment results].

This study focuses on the investigation of 35 foreign patients diagnosed as having pulmonary tuberculosis and treated at National Chiba-Higashi Hospital and the Chiba Anti-Tuberculosis Association between 1987 and 1991. All of the patients had lived in Japan less than five years. A large number of the patients were in their 20s. The chest X-rays of 24 cases (70%) revealed cavitary and sputum smear cultures for Mycobacterium tuberculosis were positive in 27 cases (77%). Many patients were in moderately advanced stages of the disease, becoming ill soon after their arrival in Japan, and being diagnosed symptomatically. Among the 35 cases, eight cases failed to finish treatment. Of those failing to finish, six were female and two were male. The results of sputum smear cultures of the patients failing to complete treatment revealed four cases that tested positive. Among those cases failing to complete treatment, four patients discharged themselves, three patients stopped during out-patient treatment, and one patient had to return to her home country because of a legal problem. A total of 14 patients were illegal immigrants: three of them failed to complete treatment because of their illegal status, and two of them due to unspecified reasons.

Adolescent↗
PubMed1993

[A case of Addison's disease caused by adrenal tuberculosis, and revealed acute hypoadrenocorticism].

We reported a case of Addison's disease, caused by adrenal tuberculosis. The patient was female, seventy four years old. She complained cough and body weight loss. She complained cough from June, 1989, but her home doctor didn't take care of her symptoms. September 1989, she felt appetite loss, and easy fatigue, so her home doctor suspected her disease as pulmonary tuberculosis, so he introduced our hospital, and she admitted. When she admitted, her chest roentogenogram revealed bIII2. Sputum smear examinations were negative. Laboratory data on admission, we observed slightly eosinophilia, severe iron deficiency anemia, and accenturation of blood sedimentation rate. Immediately after admission, she complained nausea, vomiting, coldness, and powerless. On 25 days after admission, she lost her senses suddenly, and her blood pressure fell 5 days after, she fell in shock state, too. We found out her blood sugar data was 29. After blood examinations, we found out that ACTH was high, cortisole, 17-KS, 17-OHCS were low. So we thought she got acute hypoadrenocorticism. We found her abdominal CT revealed calcification in her right adrenal gland. We diagnosed her disease as Addison's disease caused by adrenal tuberculosis so we began to give prednisolone, 7.5 mg per day. After giving, her state made better. We thought her disease as Addison's disease caused by adrenal tuberculosis, revealed acute hypoadrenocorticism.

Addison Disease↗
PubMed1993

[Investigation of tracheo-bronchial tuberculosis cases].

A total of 1397 patients were admitted to our hospital between 1986 and 1992. Of those patients, 68 were diagnosed as having tracheo-bronchial tuberculosis, when examined using a bronchofiberscope. We investigated the cases of 50 patients who were examined during the early stages of the diagnosed them as having pulmonary tuberculosis. The number of women in the group was larger than men, and young patients made up 30% of the group. Upon admission to the hospital, all of the patient's sputum examinations were tested positive, but their chest roentgenograms did not show a progressive stage. After treatment, patient roentgenograms showed improvement, however there was no improvement in tracheo or bronchial conditions. It was therefore believed that therapy was impeded by tracheobronchial tuberculosis, but only one patient was treated surgically. It was deemed that the delay of patients seeking treatment was not long, however, the delay for doctors in beginning therapy was very long. Many of the patients with tracheo-bronchial tuberculosis complained of coughing and sputum, therefore diagnosis and therapy should be performed as soon as possible.

Adolescent↗
PubMed1993

[A case of local reactivation of tuberculous peritonitis with suspected gastric submucosal tumors after laparotomy].

After complaining of right hypochondrial pain, a 36-year old man was diagnosed as having a gastric submucosal tumor at a nearby hospital and admitted to Chiba Cancer Center Hospital. On admission, a hard and immobile mass was palpable on the right upper quadrant. Laboratory findings were within normal limits. A chest X-ray revealed bilateral pleural adhesions and streaking shadows in the bilateral lung area. These findings were assumed to be due to a prior tuberculous infection. Upper gastrointestinal series and endoscopic examination showed a protruding lesion on the stomach body. An abdominal CT showed another lesion adjacent to the stomach antrum. A resection was carried out under the presumptive diagnosis of multiple gastric submucosal tumors. Exploration of the abdomen revealed widespread fibrous adhesion suspected to be due to prior old tuberculous peritonitis. Two tumors were located here. One was adjacent to the stomach body, and the other was adjacent to the liver and abdominal wall. Pathologically, both were caseated necrotizing granulomas composed of mature epithelioid cells and Langhans giant cells. A close examination revealed that one originated from the serosa of the stomach and the other from the peritoneum. Both were believed to be relatively new lesions. Pus obtained from the tumors tested positive for acid-fast bacilli. A post-operative tuberculin skin test was given and checked highly positive. From these findings, this case was diagnosed as local reactivation of old tuberculous peritonitis. After antituberculous chemotherapy at our hospital, the patient was discharged and sent home without any symptoms. The reason for the local reactivation was unknown.

Adult↗
PubMed1993

High accumulation of 2-deoxy-2-fluorine-18-fluoro-D-galactose by well-differentiated hepatomas of mice and rats.

The potential application of 2-deoxy-2-[18F]fluoro-D-galactose for the detection and evaluation of hepatomas with PET was examined in mouse and rat liver tumor models. Biodistribution studies showed that uptake of this marker was high in well-differentiated, spontaneous hepatoma of C3H mice at almost 92% of the normal liver level. The uptake by well-differentiated Morris rat hepatoma (5123D) was relatively high and second to that of the C3H hepatoma. On the other hand, uptake values for poorly differentiated mouse hepatoma (MH129P), rat hepatomas (AH109A, AH272), mouse melanoma (B-16) and mammary carcinoma (FM3A) were very low and only 14%-18% of that in the normal liver. The results suggest that while well-differentiated hepatomas maintain a high galactose metabolic activity, poorly differentiated hepatomas or other tumors lose this to a large extent. Consequently, this radiopharmaceutical can be used with PET for biochemical characterization of hepatomas and the differential diagnosis between hepatomas and other cancers.

Animals↗
PubMed1993

[Investigation of self-discharged patients of pulmonary tuberculosis].

This study investigates 27 cases in which the patients left hospital care without permission for personal reasons. These patients were classified as "self-discharged patients". Each of the patients had been diagnosed as having pulmonary tuberculosis, and were receiving treatment at the National Chiba Higashi Hospital during the period from January 1988 to July 1991. Disease was in an advanced stage in each of the patients when admitted: all sputum examinations were positive and chest roentgenograms revealed cavities in 26 patients. In addition to pulmonary tuberculosis, the patients were also diagnosed has having a variety of other medical complications such as diabetes mellitus, gastric ulcers and liver disease. Many of them were unemployed or were day labors. Reasons attributed to patients self-discharge from the hospital included repetition of alcohol drinking and unauthorized outings. At the time patients chose to leave hospitalization 11 cases checked positive for sputum examinations, and 16 cases never returned to complete therapy. Many of them were rated as high risk patients for pulmonary tuberculosis because they had no immediate family, did not own a residence or have regular employment thus economic and psychological conditions were very low. There is a high possibility that these individuals will suffer pulmonary tuberculosis relapse and become infectious bacteria carriers. It is important that such patients be hospitalized long enough to receive adequate treatment to prevent then from becoming infectious carriers and spreading disease.

Adolescent↗
PubMed1992

Isolation and sequence of a developmentally regulated putative novel gene, priA, from the basidiomycete Lentinus edodes.

Screening for gene(s) homologous to v-Ha-ras (Harvey rat sarcoma viral ras gene) in the basidiomycete, Lentinus edodes, resulted in the isolation of a novel gene (designated priA), in addition to a ras gene homologue [Hori et al., Gene 105 (1991) 91-96]. The priA gene has a coding capacity of 258 amino acids (aa) interrupted by two short putative introns. The 5'-upstream region of priA contains GGGCGG box, CCAAT box, TATAAA box and CT sequence elements in 5'----3' order. One transcription start point (tsp) was located 10 nucleotides upstream from a TATAAA box and another tsp just in a CT sequence. The deduced PRIA protein (26.7 kDa), rich in Ser (42 residues), Pro (29 residues) and Thr (27 residues), contained different types of putative zinc-binding motifs. It initiated with a hydrophobic aa sequence and terminated with the unique sequence, Cys-Aaa-Aaa-Xaa (where Aaa is aliphatic aa and Xaa is any aa), implying an association with the inner membrane surface via acylation of the Cys residue. The priA gene expression was found to be developmentally regulated with primordia/immature fruiting bodies having much higher levels of priA transcript. Preprimordial mycelia and mature fruiting bodies, however, contain very low levels of priA transcript. The priA gene may play a role during the beginning of fruiting.

Amino Acid Sequence↗
PubMed1992

[Maternal carriage and vertical transmission of group B Streptococcus (GBS)].

The pneumonia, sepsis and meningitis are common diseases of GBS infection in infants. There are early-onset and late-onset types in this disease, the result of the infection is unknown. M. Sugiyama reported that M9 is a new type of GBS in Japan in 1989. Analysis of GBS typing and serum specific antibody concentrations of the type are simple with new technics. By studying the infants' contamination we discovered that GBS appeared to originate from mother-infant sources. The infants were followed for a year. 52% of the infants had GBS contamination in their throat or stool. The most common type was Ia, followed by III, JM9 and NT6. Those types without III type had been present for more than 9 months in the infant. The contamination term of Ia or III type in infants correlated with the blood specific antibody concentration of the type.

Carrier State↗
PubMed1992

An endocrinological study of persistent pubertal macromastia.

We performed an endocrinological study on three males with persistent pubertal macromastia. The blood testosterone (T) level in these patients was either elevated or at the upper normal limit, estrone (E1) and estradiol (E2) levels were high, and T/E1 and T/E2 ratios were decreased. Persistence of low T/E1 and T/E2 ratios was thought to be the cause of the macromastia. Results of therapy using drugs (cyproterone acetate, tamoxifen citrate, danazol, and clomiphene citrate) were unsatisfactory. Persistent pubertal macromastia is an extreme condition of physiological pubertal gynecomastia, a transient phenomenon in more than half of pubertal males. It is a pathological condition characterized by a great degree of breast enlargement and abnormal endocrinological findings, and its clinical course and treatment are different from those of physiological pubertal gynecomastia.

Adolescent↗