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Biomedical subjects

Y Hirai

Publications and source records attributed to Y Hirai.

At least 73 records · Page 4Linked to original sources
PubMed2000

Site-specific integration of an adeno-associated virus vector plasmid mediated by regulated expression of rep based on Cre-loxP recombination.

Recombinant adeno-associated virus (AAV) type 2 has attracted attention because it appears to have the potential to serve as a vector for human gene therapy. An interesting feature of wild-type AAV is its site-specific integration into AAVS1, a defined locus on chromosome 19. This reaction requires the presence of two viral elements: inverted terminal repeats and Rep78/68. Accordingly, current AAV vectors lacking the rep gene lack the capacity for site-specific integration. In this report, we describe the use of Cre-loxP recombination in a novel system for the regulated, transient expression of Rep78, which is potentially cytotoxic when synthesized constitutively. We constructed a plasmid in which the p5 promoter was situated downstream of the rep coding sequence; in this configuration, rep expression is silent. However, Cre circularizes the rep expression unit, directly joining the p5 promoter to the 5' end of the rep78 coding sequence, resulting in expression of Rep78. Such structural and functional changes were confirmed by detailed molecular analysis. A key feature of this system is that Rep expression was terminated when the circular molecule was linearized and integrated into the chromosome. Using this regulated expression system, we attempted site-specific integration of AAV vector plasmids. A PCR-based assay and analysis of fluorescence in situ hybridization showed that the AAV vector sequence was integrated into chromosome 19. Sequence analysis also confirmed that transient expression of Rep78 was sufficient for site-specific integration at the AAVS1 locus, as is observed with integration of wild-type AAV.

Base Sequence↗
PubMed2000

Chromosomal localization of 18S rDNA and telomere sequence in the aye-aye, Daubentonia madagascariensis.

Chromosomal localization of 18S rDNA and telomere sequence was attempted on the chromosomes of the aye-aye (2n = 30) using fluorescence in situ hybridization (FISH) and primed in situ labeling (PRINS), respectively. The rDNA was localized at the tip or whole of the short arm of acrocentric chromosomes 13 and 14 in all spreads observed. However, post-FISH silver-nitrate (Ag) staining showed that transcriptional activity of the rRNA genes was variable, particularly in chromosome 14, which was most frequently negative in one homologue carrying the smaller copy number of rDNA. This observation supports, at the molecular cytogenetic level, previous data concerning the relationship between the copy number of rDNA and its trancriptional activity. On the other hand, telomere sequence was localized only at the telomeric region of all chromosomes, the so-called telomere-only pattern, a characteristic similar to that of the greater bushbaby. These data may provide information on the chromosomal evolution of the lemur, because locations of rDNA and telomere sequences frequently offer important clues in reconstruction of karyotype differentiation.

Animals↗
PubMed2000

Technique to investigate the temporal phase shift between L- and M-cone inputs to the luminance mechanism

We describe a technique to estimate the intrinsic phase shift between long-wavelength-cone (L-cone) and middle-wavelength-cone (M-cone) signals in the luminance mechanism with minimal contamination by chromatic mechanism(s). The technique can also estimate, simultaneously with the phase shift, the weight ratio of L and M cones for the luminance mechanism. We measured motion identification thresholds for a 1.0 cycle/deg, 12.0-Hz sinusoidal grating representing different vector directions in L- and M-cone contrast space. The physical phase of the L- and M-cone signals was varied over a broad range between -150 deg and +150 deg to investigate the effect on the threshold contours. The slope of the threshold contour in cone contrast space varied as a function of the physical phase. Estimates of the intrinsic phase shift between L and M cones are based on the change in slope of the threshold contour. The estimates are consistent with previous reports and show that whereas the L-cone signal lags behind the M-cone signal by approximately 35 deg for an orange background, the M-cone signal lags behind the L-cone signal by approximately 8 deg for a green background.

Journal Article↗
PubMed2000

Effect of Er:YAG laser irradiation on acid resistance to bovine dentin in vitro.

Resin bond strength to Er:YAG laser irradiated dentin has been reported to be lower than that of unlased dentin. The reasons have been much discussed, but not clarified. One hypothetical cause has been discussed that lased dentin is acid resistant, therefore, the etching effect of acid conditions decreases. The purpose of this study was to evaluate the acid resistance of laser-irradiated dentin and compare it with the dissolved mineral of Er:YAG laser irradiated dentin and unlased dentin. This experiment was a pilot study to assess the etching effect of pre-conditioner for resin bonding to lased dentin. Bovine dentin was irradiated by Er:YAG laser and immersed in 0.1 M lactic buffer solution (pH 4.0). The dissolved Ca and P in the solution were then both measured. Dissolved Ca from lased dentin was not significantly different from that coming from unlased dentin (p > 0.05). The molar ratio of Ca/P did not differ significantly between lased and unlased dentin, either (p > 0.05). Under FE-SEM view before immersion, the dentin surface was covered with a smear layer in unlased dentin, but this layer was not clearly observed in lased dentin. These results suggested that the lased dentin had little or no resistance to lactic buffer solution.

Acid Etching, Dental↗
PubMed2000

An anomalous case of the hepato-spleno-mesenteric and the gastro-phrenic trunks independently arising from the abdominal aorta.

This report describes an arterial anomaly case in the celiaco-mesenteric region, which was encountered in a Japanese male cadaver in the dissecting room at Kurume University School of Medicine in 1999. In this case, the usual celiac trunk was not identified, and the hepato-spleno-mesenteric and the gastro-phrenic trunks were independently arising from the abdominal aorta. In addition, the common hepatic artery divided into the left hepatic, the right hepatic, and the gastroduodenal arteries simultaneously, then, the accessory gastric artery arose from the left hepatic artery. This type of arteral anomaly belongs to the Type III of Adachi's classification and the Type II of Morita's classification.

Aged↗
PubMed2000

Two anomalous cases of the hepato-mesenteric and the gastro-splenic trunks independently arising from the abdominal aorta.

This report describes two arterial anomaly cases in the celiaco-mesenteric region, which were encountered in two Japanese male cadavers in the dissecting room at Kurume University School of Medicine in 1999. In these cases, the usual celiac trunks were not identified, and the hepato-mesenteric and the gastro-splenic trunks were independently arising from the abdominal aorta. Moreover, in the first case, the common hepatic artery passed ventral side of the portal vein and divided into the hepatic proper and the gastroduodenal arteries. This type of arterial anomaly belongs to the Type V of Adachi's classification and the Type IV' of Morita's classification. In the second case, the common hepatic artery passed dorsal side of the portal vein and divided into the hepatic proper and the gastroduodenal arteries. This type of arterial anomaly belongs to the Type VI of Adachi's classification and the Type IV' of Morita's classification.

Aged↗
PubMed2000

[Dental treatment for the handicapped by a combination of public community, dental association and university hospital--a system of Suginoki Dental Clinic].

Suginoki Dental Clinic, which is managed by Suginami Dental Association, financially supported by Suginami City, and technically assisted by the University Hospital, Tokyo Medical and Dental University, was established for dental treatment of handicapped persons living in Suginami City, Tokyo who are difficult to be treated by private practitioners. It has one full-time dentist, 12 part-time dentists, two dental hygienists, one nurse, and one clerk; one of the part-time dentists practices twice a week there. Since December 1994, 406 patients visited the clinic and the total cases was 9,273 in December 1999; 99 cases were mentally retarded, 36 autism, and 30 epileptic patients in the younger group; and 65 cases were cerebrovascular disease and 27 cardiac malfunction patients in the older group. Almost all the patients needed special care such as monitoring, intravenous sedation, nitrous oxide sedation, and general anesthesia. Four cases underwent general anesthesia, and no complication was seen among the cases. It was concluded that the clinic has been successful due to a good relationship among the Dental Association, Suginami City, and the dental hospital.

Community Dentistry↗
PubMed2000

[Postoperative interstitial pneumonia: 2 cases after lobectomy].

Two patients with postoperative interstitial pneumonia are reported. Preoperative diagnosis was primary lung cancer without idiopathic interstitial pneumonia (IIP). Within one week after operation acute interstitial pneumonia (AIP) occurred on the nonoperated side and developed. Steroid therapy was performed but one was dead. AIP is a fatal complication after pulmonary resection and steroid therapy may be useful in some cases of postoperative AIP.

Adenocarcinoma↗
PubMed2000

[A resected case of large cell neuroendocrine carcinoma].

Large cell neuroendocrine carcinoma (LCNEC) is a rare lung cancer and it has a poor prognosis. We describe our experience with a patient in whom LCNEC was diagnosed. 38-year-old woman who complained of a cough and low grade fever up was admitted to our hospital. Chest X-ray and CT shoued 6.5 x 5.0 mass in rt-S1 and S2. It was suspected as LCNEC of the right lung because of broncopscopic cytology. The upper lobectomy of the right lung and desection of mediastinal lymph nodes were performed. Pathological diagnosis was III B (T2N2M0) LCNEC. Four weeks after the operation, one cycle of chemotherapy (CDDP + VP - 16 + VDS) and one cycle of chemoradiotherapy (thoracic radiation of 40 Gy, CDDP + 5 - FU) were performed. There are no findings of tumor recurrence 7 months after operation.

Adult↗
PubMed2000

[The analysis of surgically treated pulmonary tuberculosis].

Between January 1990 and December 1999, thirteen patients with pulmonary tuberculosis underwent surgical management in our hospital. The purpose of surgery was classified into three groups: drug-resistant or persistent disease (7 patients), hemoptysis (3), and the others. We have no operative death, but have two late deaths due to postoperative persistent positive sputum and progressive tuberculosis infection. One patient relapsed one year and six months after operation and medical treatment was done successfully. Pulmonary resection is useful for localized pulmonary tuberculosis even drug-resistant cases.

Adult↗
PubMed2000

[Evaluation of adverse effects including neurotoxicity of combination chemotherapy with paclitaxel and carboplatin].

The adverse effects of combination chemotherapy with paclitaxel and carboplatin, including neurotoxicity, arthralgia and muscle pain, were evaluated in 21 patients (30 courses) using questionnaires of the Gynecologic Oncology Chemotherapy Joint Research Group. The scores of pain and numbness peaked from the third to fourth day of treatment. Although the pain score improved subsequently, the numbness score persisted at a high level. Compared to the first and second courses, the peak pain score was higher and persisted for a longer duration in the fifth and sixth courses. Using the questionnaires, we were able to recognize a high incidence of numbness and pain in patients on combination chemotherapy with paclitaxel and carboplatin, and identify the degree and temporal changes of the adverse effects. Our results suggest that the questionnaires used in this study are clinically useful for evaluating the degree and clinical course of pain and numbness in anticancer chemotherapy.

Antineoplastic Agents↗
PubMed2000

[Effect of alcohol intake on dietary habits and obesity in Japanese middle-aged men].

The amount of alcohol intake has been increasing in Japan. We investigated whether this might affect dietary habits in middle-aged men. In 1989, we conducted a health examination of 809 Japanese males aged 40-69. Food and nutrient intakes were estimated from 24-hour dietary recall. Mean values of total energy, protein, fat, and carbohydrate were evaluated according to alcohol intake. Consumption of total calories and proteins, especially animal proteins, increased and carbohydrate intake decreased proportionately with the amount of alcohol intake. Meat, fish, and soybean intake were increased in heavy drinker, along with niacin, sodium, and phosphorus intake. Despite their higher caloric intake, moderate and heavy drinkers were not more obese than non- or light-drinkers. Japanese heavy drinkers took more animal protein and sodium instead of carbohydrate compared to non- and light- drinkers. In our series, heavy drinking was not related to obesity.

Adult↗
PubMed2000

Influence of different acid conditioners on the tensile bond strength of 4-META/MMA-TBB resin to Er:YAG laser-irradiated bovine dentin.

PURPOSE: This study evaluated the effect of acid conditioners on resin bonding to dentin following irradiation with an Er:YAG laser and investigated the characteristics of resin bonding to the laser-treated dentin. MATERIALS AND METHODS: Extracted bovine teeth were cervically sectioned to expose a dentin surface. After polishing, the dentin was irradiated with an Er:YAG laser. Aqueous solutions of 10% citric acid (10-0) or 10% citric acid/3% ferric chloride (10-3) were then applied to the laser-treated surface as acid conditioners. After the acid treatment, a PMMA rod was bonded to the irradiated dentin using 4-META/MMA-TBB resin, and miniaturized dumbbell-shaped bonded specimens were prepared. These specimens were subjected to tensile testing, and fractured surfaces were observed with field-emission scanning electron microscopy (FE-SEM) to determine the mode of fracture. Additionally, the resin-dentin interfaces were observed under FE-SEM. RESULTS: The tensile bond strength of acid-conditioned bonded specimens was lower than that of specimens not subjected to acid treatment (11.1 MPa) in the laser-irradiated group. No significant difference was observed between 10-0 and 10-3 treatments. 10-3 treatment yielded the highest bond strength (24.6 MPa) in the nonirradiated group, as opposed to only 7.7 MPa in the laser-treated group. Cohesive failure in the dentin was observed in almost all specimens in the irradiated group. Furthermore, a 10- to 30-micron-thick resin-penetrated layer was observed at the interface between the dentin and resin. CONCLUSION: These results suggest that the effect of acid conditioners on resin bonding to dentin differs according to whether the dentin has been laser irradiated or not.

Acid Etching, Dental↗
PubMed1999

Assessment of the revised International Federation of Gynecology and obstetrics staging for early invasive squamous cervical cancer.

OBJECTIVE: The aim of this study was to investigate the value of the International Federation of Obstetrics and Gynecology (FIGO) classification (1995) for early invasive cervical cancer. Methods. Clinico-pathological analysis was performed in 402 patients with invasive squamous cervical cancer in whom the depth of stromal invasion was 5 mm or less. RESULTS: The incidence of lymph node metastasis was 1.2% (1/82) in patients with 3 mm or less depth of invasion; the node-positive patient was in stage IA1. The incidence of lymph node metastasis was 6.8% (5/73) in patients with 3-5 mm depth of invasion; this increased with increasing horizontal spread from 3.4% for 7 mm or less to 9.1% for more than 7 mm. None of the patients in this series had metastasis to the parametrial tissues. Of 4 patients with recurrence, 3 had horizontal spread of more than 7 mm and the remaining patient was in stage IA2. CONCLUSION: The FIGO definition of early squamous cervical cancer is generally acceptable in its present form.

Adult↗
PubMed1999

Low-grade endometrial stromal sarcoma with cardiovascular involvement--a report of three cases.

BACKGROUND: In low-grade endometrial stromal sarcoma, it has been reported that vascular space involvement in surgical specimens is found in over 50% of patients. However, in contrast to intravenous leiomyomatosis, it has been thought that further tumor extension to large vessels is rarely observed. CASES: We present three cases of low-grade endometrial stromal sarcoma with cardiovascular involvement by recurrent tumors observed on imaging studies. Two cases demonstrated tumor infiltration inside the inferior vena cava while the other case showed tumor growth in the left ventricle. CONCLUSION: This report suggests that attention should be paid to the possibility of cardiovascular invasion during the entire course of this disease.

Adult↗
PubMed1999

Utility of the monoclonal antibody HIK1083 in the diagnosis of adenoma malignum of the uterine cervix.

OBJECTIVES: The aim of this study was to qualify a staining technique for the diagnosis of adenoma malignum. METHODS: The gastric mucin expression of adenoma malignum, ordinary endocervical adenocarcinoma, and normal cervical glands was immunohistochemically compared using the monoclonal antibody HIK1083. RESULTS: The three categories were clearly distinguished, with 90% (9/10) of cases with positive adenoma malignum, 30% (3/10) of cases with weakly positive ordinary cervical adenocarcinoma, and no (0/10) cases of positive normal cervical glands. CONCLUSIONS: This preliminary report indicates that the use of HIK1083 is valuable in the diagnosis of adenoma malignum.

Adenoma↗