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Biomedical subjects

K Aoki

Publications and source records attributed to K Aoki.

At least 595 records · Page 33Linked to original sources
PubMed1990

Analysis with restriction endonucleases recognizing 4- or 5-base-pair sequences of human adenovirus type 3 isolated from ocular diseases in Sapporo, Japan.

A total of 49 adenovirus type 3 (Ad3) strains from patients with epidemic keratoconjunctivitis at an eye clinic in Sapporo, Japan, from 1983 to 1986 were classified into either genome type Ad3f (26 strains) or Ad3g (23 strains). By the use of Hinf1 and TaqI restriction endonucleases, they were classified into 11 and 3 subgenome types, respectively. During this observation period, two epidemics of Ad3 infection relating to epidemic keratoconjunctivitis occurred. The prevalent Ad3g strains isolated during the epidemic in 1983 belonged to a single subgenome type. However, in the course of the Ad3f epidemic in 1986, alteration of one subgenome type of the prevalent strain to a different subgenome type which was presumed to be a derivative of the former was observed. In the years in which only a few Ad3 strains were isolated, such Ad3f strains were classified into different subgenome types. However, all Ad3g strains except two belonged to the same subgenome type.

Adenoviruses, Human↗
PubMed1990

Generation of a different type of beta-kallikrein from porcine pancreatic alpha-kallikrein by the action of chymotrypsin--observation of proteolytic processing occurring around "kallikrein autolysis loop" region.

The generation of a different type of beta-kallikrein, designated C beta-kallikrein, from alpha-kallikrein by chymotryptic action was ascertained by the following observations: 1) When alpha-kallikrein was incubated with chymotrypsin, an increase of esterolytic activity of kallikrein was observed. 2) In sodium dodecyl sulfate polyacrylamide gel electrophoresis, C beta-kallikrein was found to be different from the beta-kallikrein obtained from alpha-kallikrein by tryptic digestion, and was designated T beta-kallikrein. 3) N-Terminal amino acid sequence analyses of internal light and heavy chains of C beta-kallikrein indicated that N-termini of the light and the heavy chains were isoleucine and lysine, respectively, and that the heavy chain had most of the "kallikrein autolysis loop" sequence in its N-terminal end. In the case of T beta-kallikrein, N-termini of the light and the heavy chains were isoleucine and alanine, respectively, and the light chain retained the "kallikrein autolysis loop" region in its C-terminal end. These observations demonstrated that C beta-kallikrein was different from the beta-kallikrein prepared from autolyzed pancreas, A beta-kallikrein, which had lost the "kallikrein autolysis loop" sequence. Structural differences of the above four kallikreins (alpha-, T beta-, C beta-, and A beta-) result in somewhat different enzyme properties. The kinetic constants for the hydrolysis of synthetic substrates (N alpha-benzoyl-L-arginine ethyl ester and N alpha-tosyl-L-arginine methyl ester) of these kallikreins differed from each other, and inhibitory profiles against alpha 1-antitrypsin were also different.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1990

Family history of cancer and mortality among patients gastrectomized because of benign gastric diseases.

A preliminary result from a cohort study on the association of a family history of cancer with mortality is discussed in this paper. Among 2200 patients (1912 males and 288 females) gastrectomized because of benign gastric diseases, 274 male patients, and 40 female patients had a family history of cancer. During 2750 person-years of observation, 22 patients with the family history of cancer were found to be dead and 111 patients without the family history died during 17,527 person-years, giving a relative risk of 1.26 (not significant). We focused on the male subjects that were followed up for more than 10 years; however, the observed/expected ratio of cancer deaths for subjects with a family history of cancer was about four times higher than that for those without family history. Since case-control studies on family history are vulnerable to biased recall and interchangeability of cases, more cohort studies like the present study should be conducted to assess the association of the family history of cancer.

Case-Control Studies↗
PubMed1990

New screening system for unruptured cerebral aneurysms--combination of an expert system and DSA examination.

We have designed a screening system to diagnose unruptured aneurysms, including the use of digital subtraction angiography (DSA). We surveyed 115 patients who had undergone clipping procedures after subarachnoid hemorrhage (SAH) and questioned them with regard to the subjective symptoms. Sixty-eight of 92 patients who returned the questionnaire reported, prior to rupture, headache, eye pain, and neck pain most frequently, and also impairment of extraocular movements, ptosis, visual field defects, and motor and sensory disturbances. Nineteen (47.5%) of 40 patients who had complete pain relief after surgery complained of headache from 1 week to 1 month before SAH. In addition, nine patients (22.5%) complained of headache for several years, and were also pain-free after surgery. For the indication of DSA, we employed an expert system based on fuzzy set theory. Seven groups of parameters are: Group 1, a basic questionnaire concerning age, sex, and past and family histories; Group 2, 15 warning signs selected on the basis of retrospective study; and Groups 3-7, detailed questions concerning each sign. Scoring weights assigned to each condition based on the results of the retrospective study, and threshold values were determined by several neurosurgeons. The certainty factors for intermediate hypotheses were calculated from these weights and threshold values and summed up, from which the conclusion was obtained. Twelve new cases of unruptured cerebral aneurysm were diagnosed using this screening system. This system may improve the ability to diagnose cerebral aneurysms before rupture.

Aged↗
PubMed1990

Reconstruction for the vertebral artery stenosis at its origin--bypass surgery using a saphenous vein graft with external shunting.

Eight patients with vertebral artery (VA) stenosis at its origin were surgically treated by a new reconstructive technique. Two patients suffered vertebrobasilar transient ischemic attacks, and five had brainstem and/or cerebellar infarction. All patients had multiple stenotic lesions, including bilateral VA stenoses in one and unilateral VA stenosis plus contralateral VA occlusion in seven. They underwent a subclavian artery to VA bypass using a saphenous short vein graft with external shunting. Postoperatively, no patients had aggravated neurological symptoms, and angiography showed all bypasses to be patent. One had an episode of transient loss of consciousness 8 months postoperatively, but the others showed no episodes of ischemia during an average follow-up period of 2 years and 10 months. The results indicate that this procedure is safer and more useful than other surgical procedures.

Aged↗
PubMed1990

[Visual scoring in the auditory brainstem response first report: judging the presence or absence of a response].

The evaluation of visual scoring in the ABR audiometry was performed by the two groups of scorers 3 experienced and 3 inexperienced. The sample traces of responses for visual scoring were obtained from 3 normal adults, and consisted of 300 which were derived from 100 each on with clicks of 0, 5, 10, 15, 20, 30 dBSL and without stimulation. The forced choice method and the five confidence level method were applied from estimation when the traces were presented to the scorers separately on duplicatively. Judgment was given twice with a 2 months intervals. Results obtained were as follows: 1. The rate of positive responses in the forced choice method was 15% at 0dB and 96% at 15dB in the experienced group. 2. In the forced choice method the lowest rate that all scorers of a group had the same judgment, was 78% at 10dB in the experienced and 55% at 5dB in the inexperienced. 3. The lowest rate of the repeated judgments were same, was 90% at 10dB in the experienced and 79% at 0dB in the inexperienced. 4. The rate of the false positive response was significantly smaller in the duplicate presentation than in the separate one. 5. A tendency of great subjectivity was observed more often in the confidence level method than in the forced choice method, especially in the inexperienced group.

Audiometry, Evoked Response↗
PubMed1990

[Rapid diagnosis of enterovirus 70 infection by detection of IgM antibodies with a biotin-avidin ELISA].

A biotin-avidin immunoassay was developed to detect IgM antibodies to enterovirus 70 (EV70) in sera from patients with acute hemorrhagic conjunctivitis. Biotinylated monoclonal antibody to EV70 and horseradish peroxidase-streptavidin were used in an indirect IgM capture ELISA. 40 acute- and convalescent-phase serum pairs were tested and 34 sera (85.0%) in the convalescent phase were positive for IgM antibodies. The positive rate of the method was much higher than that of the non-biotin-avidin system for EV70 (55%). Two sera in the acute phase, which were negative for neutralizing antibodies, had IgM antibodies. Two serum specimens which had been collected a third time from 2 patients during the seventh week after onset were positive for IgM, showing that EV70 IgM lasts at least for one month and a half. The biotin-avidin ELISA is sensitive and can be performed in 2 days instead of 3 days for the non-biotin-avidin method, and is useful for rapid diagnosis of EV70 infection.

Antibodies, Viral↗
PubMed1990

[Morphological studies on the roots of maxillary premolars in Japanese].

Visual observations were made of 3,202 maxillary first premolars and 3,365 maxillary second premolars from subjects of known sex, age, and side attributes. The material belongs to the Okamoto Research Laboratory of Dentistry. Items observed for each donor included number of dental roots, shapes of root apexes, root grooves, root orientation and curvature, and conditions of the maxillary first and second premolars. Results 1) In 65.7% of all materials (55.4% in males and 76.1% in females), maxillary first premolars had primary single roots. Complete branched roots accounted for 25.5% of the male and 17.6% of the female materials. In both cases, there was significant distinction between the sexes. Triple root teeth were extremely rare in both male- and female-donor teeth, as were double rooted maxillary second premolars. 2) Protruding, circular, and flat root apex types occurred in both maxillary first and second premolars. Circular and flat types were common among males. Branched and double-root maxillary first and second premolars were of either the complete or the incomplete type, both of which were more common in males. 3) About half of the mesial surface grooves in single-root maxillary first premolars were deeper than distal surface grooves in the same teeth: In 1/4-branch double teeth, 28.8% of the mesial surface grooves were deeper than the distal-surface grooves. The corresponding percentage for 1/3-branch double teeth was 38.8%. In 7.6% of 1/4-branch and 17.4% of 1/3-branch double teeth, distal-surface grooves were deeper than mesial-surface grooves. In 36.4% of 1/4-branch double teeth and 28.9% of 1/3-branch double teeth, the lower portion of the root was web shaped. In maxillary first premolars, lingual roots of 1/3-branch double-root teeth were cylindrical, as were 28.9% of buccal roots. Root grooves occurred on the lingual sides of 61.7% of all specimens. For 1/2-branch double root teeth, 18.4% were cylindrical: and 62.7% had grooves on the lingual side. Results are essentially the same in both cases. 4) Straight dental roots occurred in 37.4% of maxillary first and 35.4% of maxillary second premolars. Roots inclined distally in 36.7% of maxillary first premolars and in 18.8% of maxillary second premolars. A variety of inclinations and curvatures was observed. Booth roots were straight in 47.5% of 2-branch maxillary first premolars, whereas 35.1% had 1 straight and 1 inclined root and 84.4% had 2 distally inclined roots.(ABSTRACT TRUNCATED AT 400 WORDS)

Bicuspid↗
PubMed1990

Alteration in sarcoplasmic reticulum-dependent contraction of tail arteries in response to caffeine and noradrenaline in spontaneously hypertensive rats.

Since the membrane Ca2+ handling properties of the arterial smooth muscle sarcoplasmic reticulum may be altered in genetic hypertension, we studied caffeine- and noradrenaline-induced contractions in tail arteries from spontaneously hypertensive rats (SHR) at the prehypertensive stage (4 weeks old) and from age-matched Wistar-Kyoto rats (WKY). After the sarcoplasmic reticulum had been loaded with Ca2+ by pretreatment with physiological Ca2+ solution, caffeine- and noradrenaline-induced contractions of the tail arteries, measured in a Ca2(+)-free solution [containing 0.1 mmol/l ethyleneglycol-bis-(beta-aminoethylether)-N,N,N',N'-tetraace tic acid], were smaller in SHR than in WKY. After caffeine-releasable Ca2+ in the sarcoplasmic reticulum had been depleted by pretreatment with the Ca2(+)-free solution, the caffeine-induced arterial contractions in a low-Ca2+ (0.5 mmol/l) solution were smaller in SHR than in WKY. The Ca2+ concentration-tension relationship in skinned arterial fibres was similar in WKY and SHR. These data suggest that the ability of the sarcoplasmic reticulum to take up and store caffeine- and noradrenaline-releasable Ca2+ is decreased in SHR. The development of hypertension in SHR may be explained by an impaired function of the sarcoplasmic reticulum in arterial smooth muscle.

Animals↗
PubMed1990

[Rapid etiologic diagnosis of epidemic keratoconjunctivitis].

We evaluated enzyme-linked immunosorbent assay (Adenoclone) in 253 cases of epidemic keratoconjunctivitis (EKC), pharyngeal conjunctival fever (PCF) and acute conjunctivitis. The clinical diagnosis due to adenoviral ocular infection was 86/114 (75%) in EKC, 26/50 (52%) in PCF and 25/89 (28%) in acute conjunctivitis, Adenoclone was positive only within 7 days after the disease onset. The specificity (87%) and sensitivity (74%) of Adenoclone were confirmed by isolate cell culture. Cases with corneal complication due to adenoviral infection show higher a value than the OD value in Adenoclone and the bulbar conjunctiva is a suitable site to detect adenoviral antigen. In this survey, isolated adnovirus type 4 was recognized in 53%, Ad8 in 14%, Ad3 in 13%, Ad37 in 5%, Ad19 in 2% and non typed Ad in 12%. Clinical findings due to Ad4 showed EKC in 50%, PCF in 30% and acute conjunctivitis in 20% respectively.

Adenovirus Infections, Human↗
PubMed1990

[Familial idiopathic vitamin E deficiency associated with cerebellar atrophy].

Sibling cases of familial vitamin E deficiency accompanied by ataxia, polyneuropathy and mental retardation were reported. Case 1 was a 37-year-old male who developed progressive gait disturbance, deformity of the feet and head tremor from childhood, after normal delivery and development of early childhood. On physical examination, he had cataract, high arched palate and pes cavus. Neurological examination revealed mental retardation (WAIS 68), scanning speech, muscular atrophy of the face and extremities with predominance in the lower limbs, absent Achilles tendon reflex, disturbance of superficial and deep sensation predominant in distal limbs, and marked gait ataxia. Ataxia was both cerebellar and sensory in nature. Laboratory data of the blood showed no significant abnormalities including blood glucose and vitamin B12 except a markedly low level of serum vitamin E. The brain CT scan revealed severe cerebellar atrophy and marked dilatation of the cisterna magna and the subarachnoid space around the cerebellum. Motor nerve conduction velocity in the leg was decreased. Biopsy specimen from the quadriceps muscle showed neurogenic atrophy. Sural nerve biopsy revealed decrease in large myelinated fibers with axonal degeneration and regeneration. Oral administration of alpha-tocopherol acetate, 600 mg per day, diminished ataxia significantly. Based on lysosomal enzyme activity in leukocytes, clinical and laboratory examination, lipidosis or spinocerebellar degeneration was excluded. Chronic lipid malabsorption or beta lipoprotein deficiency which can cause decrease in vitamin E absorption, was not recognized. On oral loading with 2 g of alpha-tocopherol acetate, the decrease rate of serum vitamin E was normal. Consequently the low vitamin E was considered to have resulted from selective impairment of vitamin E absorption.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

A sensitive assay for anti-phosphatidylethanol-amine antibody in patients with recurrent fetal loss.

There is strong evidence that anti-phospholipid antibodies is implicated in thrombosis and recurrent fetal death. In recent years, it has been suggested that anti-phosphatidylethanolamine (PE) antibody is an important antibody of this type. In the present study, we established a sensitive enzyme linked immunosorbent assay (ELISA) to detect anti-PE antibodies and examined the relationship between the anti-PE antibody level in serum and recurrent abortion. The improvement of the assay was made by treating PE with 1.0% acetic acid in methanol solution prior to its application to the microplates. This treatment markedly increased the antigenicity of PE. Using this modified ELISA, anti-PE antibodies in 10 patients with a history of recurrent fetal loss were measured before and after therapy during the last period of their pregnancies. IgG anti-PE antibodies were detected in all 10 patients. Four patients exhibiting high titers of IgG anti-PE antibody experienced subsequent intrauterine fetal death (IUFD), while the other 6 patients, whose titers of IgG anti-PE antibody had decreased with therapy, had live births. These results suggest that this modified ELISA for estimating IgG anti-PE antibody is a valuable tool for the diagnosis and prognosis of patients with recurrent fetal loss.

Abortion, Habitual↗
PubMed1990

Aberrant right gastric vein directly communicating with left portal vein system. Incidence and implications.

In 3 patients with primary hepatic malignancies, a communication between the right gastric vein and the left portal vein system was recognized at angiography. The right gastric vein entered directly into the left lateral portal veins in 2 patients and into the left medial portal veins in one. Portal angio-CT performed in one patient demonstrated a specific defect only in the left lateral superior area of the liver, consistent with the segmental opacification of the portal vein branch recognized on the angiogram. This rare communication was seen in 3 (1.5%) of 200 consecutive patients who underwent celiac angiography and is most likely an anomaly in which the right gastric vein directly enters the left portal vein instead of the portal vein trunk. When interpreting a filling defect not associated with a mass lesion on portal angio-CT for hepatic neoplasms or the right gastric vein communicating with the left portal vein system on the angiogram, this particular anomaly should be considered.

Adult↗
PubMed1990

[Studies on evaluation of risk factors of cancer by a large-scale cohort study newly organized in Japan--planning and pilot study].

A large-scale cohort study has been planned in cooperation of 22 epidemiologists in Japan since 1986. The objective of this new cohort aged more than 40, consisting the inhabitants throughout Japan is to evaluate risk factors of cancer already known and suspected agents in so rapidly changing society of Japan where age-sex contraction of population, disease pattern and lifestyle habits have remarkably changing for the last decades. The factors examined are not only social factors but also biological ones from blood, serum and other body fluids. At the same time serum bank of healthy inhabitants in Japan is established in this study.

Cohort Studies↗
PubMed1990

Mortality of hematopoietic disorders and hair dye use among barbers.

A total of 8,316 barbers were followed up from 1976 to 1987 to examine the relations between hair dye use and deaths from hematopoietic disorders. The follow-up rate was about 95%. Three leukemia deaths and two malignant lymphoma deaths were observed in this cohort. The observed deaths were less than the expected number calculated from age- and sex-specific mortality of the general population in Japan (3.8 and 3.0, respectively). No deaths from aplastic anemia or the other hematopoietic disorders were observed.

Adult↗