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T Koshino

Publications and source records attributed to T Koshino.

At least 55 records · Page 3Linked to original sources
PubMed2000

Developmental changes in mitochondrial activity and energy metabolism in fetal and neonatal rat brain.

Experiments were undertaken to investigate mitochondrial activity and energy metabolism in the developing rat brain from the late fetal stage to the neonatal stage. Samples of cerebral cortical tissue were obtained from fetuses at 14, 16, 18, and 20 days of gestation, and from pups at 1 h, 1 day and 7 days after birth. Mitochondrial respiration was measured polarographically using homogenates. Fetal and neonatal brains were frozen in situ and fluorometric enzymatic techniques were used for the analysis of ATP, ADP, AMP, and lactate. In the fetal brain, there was a gradual increase in stimulated (+ADP) and uncoupled respiratory rates using glutamate and malate as substrates, from 14 days to 20 days of gestation, together with a moderate increase in ATP concentration and in the sum total of adenine nucleotides, and a significant decrease in lactate. Since non-stimulated (-ADP) respiratory rates did not change with increasing gestational age, the respiratory control ratio appeared to increase over the same period. An increase in mitochondrial activity was more pronounced immediately after birth, together with a marked increase in ATP concentration and in the sum total of adenine nucleotides. The highest rate of mitochondrial respiration was observed in 1-hour-old pups. These results indicate that, in the rat brain, there is maturation of oxidative metabolism in mitochondria that is initiated in late gestation. Acceleration in mitochondrial respiration occurs immediately after birth in order to maintain high-energy phosphate levels, and this may be crucial for the successful outcome of the newborn.

Adenosine Diphosphate↗
PubMed2000

Posterior pulmonary lobe: segmental and vascular anatomy in human specimens.

The posterior pulmonary lobe (PPL) is defined by an aberrant fissure running horizontally on the costal surface of the lower lobe. We studied the frequency of the PPL, and the ramification of bronchi and vessels in the PPL, and so describe mainly these differences compared to the normal lung. Nineteen PPL cases (15 right and 4 left) were found in 273 (116 right and 157 left) human lung specimens. The incidence of PPL was 13% on the right side and 3% on the left side. The PPL frequently (right 87%, left 50%) corresponded to S(6) (superior segment). Analysis of the ramification of bronchi revealed that B(7) (medial basal bronchus) tended to form a common trunk with B* (subsuperior bronchus) or B(8) (anterior basal bronchus). Analysis of the ramification of veins revealed that V(6) (superior vein) tributaries were often double, and V(6) tended to disperse widely. Anomalies in which the segmental artery and vein communicated with other segments were found in seven cases (37%) (4 arteries and 3 veins, 6 right and 1 left) in PPL. These results show that the PPL does not always correspond to S(6) and frequently has an anomalous vessel from other segments. This is valuable surgical information, particularly in S(6) segmentectomy.

Bronchi↗
PubMed2000

Total arch replacement with an aortic arch aneurysm due to chronic interstitial pneumonia: report of a case.

The case of a 66-year-old man who had rheumatoid arthritis, chronic interstitial pneumonia (IP) with honeycomb lung, and an aortic arch aneurysm is described. He complained of left chest pain in April 1998 and chest computed tomography revealed an enlargement of a thoracic aneurysm whose maximum diameter reached 7 cm. He was urgently transferred to our institution to undergo immediate surgery for an impending rupture of the aneurysm. His PaO2 with 80 Torr with oxygen therapy. The operation included a median sternotomy, extracorporeal circulation with selective cerebral perfusion, the use of cold blood cardioplegic solution, and open distal anastomosis. Although an acute exacerbation of IP occurred 2 months after the surgery, he successfully received intensive care including high-dose steroid therapy and artificial ventilation. He was successfully weaned from the ventilator and is now being followed up with medical treatment.

Aged↗
PubMed2000

Successful surgical treatment of giant coronary artery aneurysm with fistula.

Giant coronary artery aneurysm with fistula formation is a rare entity. We report a giant coronary artery aneurysm with a maximum diameter of 70 mm with fistula, in which a favorable course was obtained after surgical treatment. We also review the literature on giant coronary artery aneurysms exceeding 50 mm in maximum diameter.

Blood Vessel Prosthesis Implantation↗
PubMed2000

Osseous tissue reaction around hydroxyapatite block implanted into proximal metaphysis of tibia of rat with collagen-induced arthritis.

This study was conducted to investigate the influence of osteoporosis on new bone formation around a hydroxyapatite (HA) block implanted into the proximal metaphysis of the tibia of rats with collagen-induced arthritis (CIA). Ten rats were immunized with an emulsion of bovine type II collagen and Freund's complete adjuvant (arthritis group). Another 10 rats, which were not immunized were used as the control group. Seventeen days after immunization, HA block was implanted into the proximal metaphysis of the tibia. Four weeks after implantation, all rats were killed. The serum level of tetrate-resistant acid phosphatase (TRAP), bone mineral density (BMD) in the proximal metaphysis of the tibia and the affinity index in the arthritis group were 28.0+/-3.5 IU/ml, 130.3+/-28.7 mg/cm2 and 77.6+/-10.8%, respectively, and those in the control group were 24.6+/-5.5 IU/ml, 175.9+/-30.5 mg/cm2 and 56.3+/-14.8%. The serum level of TRAP was higher (P < 0.05) and BMD was lower (P < 0.005) in the arthritis group. The amount of new bone formation around the HA block was larger (affinity index, P < 0.05) in the arthritis group than in the control group. These findings suggest that bone formation around HA block might be enhanced even in conditions associated with highly activated bone resorption and bone formation, such as arthritis.

Animals↗
PubMed2000

Distribution of neuropeptides in synovium of the knee with osteoarthritis.

Synovial tissue was obtained from medial, lateral, and suprapatellar sites of 21 knees (15 patients) with medial compartmental osteoarthritis at surgery. All patients reported pain around the medial joint of their knees while walking and climbing stairs. For investigation of the synovial innervation, six samples were stained with modified gold chloride and the others with an immunohistochemical method using antisera against neuropeptides. The extent of synovitis in each part was scored using a new 10-point scale. The results showed that the synovium had an extensive neural network in the somatic and autonomic nervous systems. Neuropeptides were most abundant, with an especially large number of substance P and calcitonin gene related peptide immunoreactive free nerve endings. Some of the substance P positive nerve endings were surrounded by monocytes. Substance P and calcitonin gene related peptide were found more frequently in the medial than in the lateral or suprapatellar areas. Substance P positive free nerve endings showed more dendritic morphologic features in the medial region than did those in the lateral and suprapatellar regions, and small nerves were accompanied by newly developed vessels in synovial villi. In the medial region, the synovitis was more remarkable than in the lateral region. These findings suggest that free nerve endings containing substance P may modulate inflammation and the pain pathway in osteoarthritis.

Aged↗
PubMed2000

Secondary mitochondrial dysfunction after transient intrauterine ischemia in the fetal rat brain.

OBJECTIVE: Recirculation following transient intrauterine ischemia has previously been found to cause partial recovery and secondary deterioration of cellular bioenergetic states in the fetal rat brain. Our objective was to assess whether secondary bioenergetic failure is due to mitochondrial dysfunction. STUDY DESIGN: Cerebral cortical tissues were obtained from 20-day-old fetal rats at the end of 30 minutes of intrauterine ischemia (n = 6) and after 1 hour (n = 6), 2 hours (n = 6), and 4 hours (n = 6) of recirculation. Mitochondrial respiratory activities were measured polarographically using homogenates. RESULTS: Mitochondrial activities decreased to 45% of sham-operated controls at the end of ischemia. Recirculation (1 hour) brought about partial recovery, but continued reflow (2 hours and 4 hours) was associated with a secondary deterioration of mitochondrial activities. CONCLUSION: The results indicate that although during the early time period after ischemia mitochondrial respiratory capacity is restored, secondary mitochondrial dysfunction develops in the immature rat brain.

Animals↗
PubMed2000

Changes in uterine and ovarian arterial impedance during the periovulatory period in conception and nonconception cycles.

OBJECTIVE: To evaluate whether the Doppler velocimetry of uterine and ovarian arteries during the periovulatory period in conception cycles differs from that in nonconception cycles. DESIGN: Transvaginal color Doppler sonography was used to assess uterine and ovarian perfusion in 63 infertile women during the periovulatory period. RESULTS: In the conception cycles (n = 16), the PI values of uterine arteries at the day of ovulation were significantly less than those in nonconception cycles (n = 47). There were no significant differences in the PI values of ovarian arteries between the conception and nonconception cycles. CONCLUSIONS: In the present study, the conception cycles showed lower vascular impedance in the uterine during the periovulatory period than did the nonconception cycles. This endometrial perfusion presents an accurate noninvasive assay of uterine receptivity that can be used to predict the successful outcome of implantation and to reveal unexplained infertility problems.

Adult↗
PubMed2000

Effect of alpha-phenyl-N-tert-butyl nitrone (PBN) on fetal cerebral energy metabolism during intrauterine ischemia and reperfusion in rats.

The objective of the present study was to explore whether a free radical spin trap agent, alpha-phenyl-N-tert-butyl nitrone (PBN), influences bioenergetic failure induced in the 20-day-old fetal brain by 30 min of intrauterine ischemia in Wistar rats. Fetal brains were frozen in situ at the end of ischemia and after 1, 2, and 4 h of recirculation for analysis of ATP, ADP, AMP, and lactate. PBN or vehicle was given 1 h after recirculation. Tissue oxygen tension was evaluated in placental and fetal cerebral tissues throughout the whole periods of 30 min of ischemia and 4 h of recirculation. Ischemia was associated with a decrease in ATP concentration and an increase in lactate concentration (p < 0.001). Recirculation (1 and 2 h) led to a recovery of ATP concentration, but continued reflow (4 h) was associated with a secondary deterioration of high-energy phosphates (p < 0.01). Lactate concentration increased during this recovery period. This deterioration was prevented by PBN (p < 0.05). After 30 min of ischemia, tissue oxygen tension in placenta and fetal brain decreased to about 30% and 50% of control, respectively. However, recirculation brought about a recovery of oxygen delivery. The results indicate that although during the early time period after ischemia fetal cerebral energy metabolism is maintained by an acceleration of the anaerobic glycolytic rate, secondary deterioration of cellular bioenergetic state develops in the immature fetal brain. This deterioration may be due to mitochondrial dysfunction, which may be induced by oxygen-derived free radicals, and not by compromised microcirculation.

Animals↗
PubMed2000

Primary aldosteronism in pregnancy.

Aldosteronism is a rare complication of pregnancy. We report a case of a 26-year-old woman who became pregnant soon after a diagnosis of primary aldosteronism due to left adrenal adenoma was made. Only oral potassium supplementation was required in addition to routine prenatal care until 36 weeks' gestation. Subsequently, antihypertensive medication was needed to control elevated blood pressure. A healthy male infant was delivered by cesarean section because of abruptio placentae. The postoperative course was uneventful. Left adrenalectomy was conducted eight months after delivery under laparoscopic visualization. In this case report, we discuss management of aldosteronism in pregnancy and review the literature.

Abruptio Placentae↗
PubMed2000

Changes in maternal lipid peroxidation levels and antioxidant enzymatic activities before and after delivery.

OBJECTIVE: Our goal was to characterize the changes in maternal lipid peroxidation levels and antioxidant enzymatic activities before and after delivery. METHODS: Predelivery and 1, 24, and 48 hours post-partum plasma concentrations of malondialdehyde, erythrocyte enzyme superoxide dismutase, glutathione peroxidase and catalase were measured in uncomplicated pregnancies. RESULTS: Malondialdehyde levels increased slightly from predelivery to 24 hours post-partum and then decreased significantly at 48 hours post-partum. At one hour post-partum superoxide dismutase and catalase levels increased significantly to about 125% and 170% of predelivery levels, respectively. Thereafter, these values decreased significantly from one hour to 48 hours post-partum. The relative changes in superoxide dismutase and catalase levels at one hour post-partum compared to predelivery values correlated significantly with the duration of labor. CONCLUSION: The results suggest that the uncontrolled lipid peroxidation caused by reactive oxygen species, which are produced in consequence of tissue reoxygenation, may occur during labor and that prolonged labor, may cause maternal oxidative stress.

Adult↗
PubMed2000

[Immunohistochemical analysis of bronchial mucosa in severe asthmatics treated with long-term, high-dose inhaled BDP].

To analyze specific mucosal changes in asthmatic patients receiving long-term, high-dose beclomethazone dipropionate (BDP) inhalation therapy, we performed bronchial mucosal biopsies and immunohistochemical analysis of patients who had been treated with or without BDP-inhalation. Our study enrolled 6 chronic severe asthmatics who were treated with 1,800 micrograms/day or more of BDP with regular use for more than 3 years (HD-BDP group), 6 mild asthmatics who were not treated with BDP (non-BDP group), and 6 control subjects. Specimens of bronchial mucosa were stained with anti-EG 2 (eosinophils), anti-UCHLA-1 (T lymphocytes) and anti-tryptase (mast cells). Although limited eosinophil infiltration was observed in the HD-BDP and control groups, a significant increase was noted in the non-BDP group. The infiltration of both T lymphocytes and mast cells exhibited a statistically significant increase in the non-BDP group compared to the HD-BDP and control groups. In chronic severe asthmatics, airway mucosal cell infiltration was reduced by high-dose and long-term inhaled BDP therapy, and BDP also relieved their asthmatic symptoms. However, in mild asthmatics, bronchial mucosal cell infiltration remained high. For such patients, we concluded that initiating BDP therapy from an early stage may bring clinical improvement and help prevent cell infiltration.

Administration, Inhalation↗
PubMed2000

[A case treated surgically through anterior axillary thoracotomy for recurrent right spontaneous pneumothorax after repeated video-assisted thoracoscopic surgery].

A 21-year-old male who had thoracoscopic surgery for right spontaneous pneumothorax was admitted to our hospital complaining of dyspnea due to the recurrence. There was no bulla in right apex but empysematous change in visceral pleura at re-thoracoscopic surgery. Two bulla in right S6 were removal using endo-stapler. Three years after the second thoracoscopic surgery, the recurrence of right pneumothorax was recognized. Chest CT revealed a new bulla in right apex. Therefore the third operation was carried out through anterior axillary thoracotomy. A new bulla was resected with endo-stapler and pleurodesis using argon laser was also applied to prevent of recurrence of pneumothorax. The patient is now doing well without recurrence 6 months after the third operation.

Adult↗
PubMed2000

Left internal thoracic artery harvesting in pleural symphyses under minimally invasive direct vision.

In minimally invasive direct coronary artery bypass grafting (MIDCAB), the internal thoracic artery (ITA) is harvested under a direct-vision or videothoracoscopic techniques. However, whatever the technique used, dense pleural adhesions hamper ITA harvesting. We describe the case of a patient who underwent MIDCAB 40 years after a pulmonary resection for tuberculosis. The parietal pleura adhered to the left lung so firmly that we could not enter the intrapleural cavity. Therefore, the ITA was harvested creating an extrapleural tunnel Although this approach resulted in more operating time and bleeding, an anastomosis between the ITA and left anterior descending coronary artery was performed successfully. We believe that MIDCAB can be carried out even in patients with dense pleural adhesions.

Aged↗
PubMed2000

[Clinical features of patients with osteoarthritic knees followed by development of rheumatoid arthritis].

We investigated clinical features of patients with osteoarthritic knees followed by development of rheumatoid arthritis (RA) after several year's interval. The subjects were 16 knees of 8 patients with osteoarthritis (OA) including one man and 7 women. The mean age at development of OA knee was 62.8 years (range; 45-73). The mean age at later development of RA was 66.0 years (range; 52-79). The mean follow-up period was 96.4 months (range; 28-191). We evaluated clinical features using the 1987 revised Criteria of the American College of Rheumatology (ACR), laboratory dates including RF, CRP, ESR, the number of joints with RA, and femorotibial angle (FTA). The mean number of features of patients which was fulfilled with the ACR criteria was 3.3 +/- 1.6 at the onset of RA. Only four patients were seropositive through the total follow-up period. The serum level of RF, CRP, and ESR were reduced at the follow-up period. The mean number of the joints involved in RA was 11.0 +/- 5.1 (range; 4-22) and wrist and shoulder joints were involved more frequently than other joints except knees. High tibial osteotomy (HTO) was performed on 5 knees of 3 patients and the mean degree of FTA was 168.8 +/- 1.9 degrees just after surgery. However, 36 months after development of RA, joint destruction and valgus deformity occurred on 3 knees and the mean degree of FTA of 5 knees was ended up to 159.6 +/- 11.3 degrees. Our experiences suggested that RF, CRP, ESR and lesions of other joints should be carefully evaluated in the OA patients with seropositivity or knee hydrarthrosis and that histological analysis for synovium should be assessed by the biopsy at time of HTO or arthroscopic surgery to improve accuracy of diagnosis.

Aged↗