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Biomedical subjects

M Ochi

Publications and source records attributed to M Ochi.

At least 181 records · Page 10Linked to original sources
PubMed1994

Further experimental evidence of selective nerve regeneration in aortic Y-chambers.

To explain the discrepancy between Weiss and Taylor's results and our recent findings about axonal growth patterns in a fresh aortic chamber, we examined whether regenerating axons show preferential growth toward a nerve piece in an aortic Y-chamber. In our previous studies, we could not reproduce their results, which showed that regenerating nerve fibres from the proximal stump of a severed peripheral nerve grew randomly in the two channels with and without a nerve segment; our results showed preferential regeneration toward a nerve segment channel. In the present study, we retraced the steps of Weiss and Taylor using white rats, the longitudinal section of the specimen, and silver staining. Despite using the same methods we were still unable to show that the growth pattern was random, but we did find preferential axonal growth into the nerve segment channel of a fresh aortic Y-chamber. The evidence of selective nerve regeneration was unequivocal and we cannot support the findings of Weiss and Taylor reported in 1944.

Animals↗
PubMed1994

[Aggressive management of prolapsed fetal membranes earlier than 26 weeks' gestation by emergent McDonald cerclage combined with amniocentesis and bladder overfilling].

During the period January, 1987-December, 1992, 32 pregnant women (33 fetuses) earlier than 26 weeks' gestation were admitted to our perinatal unit with incompetent cervix and prolapsed fetal membranes through the cervix (hourglassing). Eighteen pregnant women (19 fetuses) were managed aggressively with emergent double McDonald cerclage, which included preoperative amniocentesis and bladder overfilling to decompress and replace prolapsed fetal membranes. Fourteen pregnant women were managed conservatively with bed rest, tocolysis, and antibiotic therapy. The perinatal results of aggressive management were clearly more favorable than those of conservative management when compared: Prolongation of pregnancy 35.2 +/- 39.7 vs. 3.5 +/- 2.6 days (p < 0.01), gestational age at delivery 27.3 +/- 5.3 vs. 24.2 +/- 1.2 weeks' (p < 0.05), birth weight 1,260 +/- 909 vs. 690 +/- 124 grams (p < 0.05), and fetal salvage rates 74(14/19) vs. 7(1/14)%, respectively.

Amniocentesis↗
PubMed1994

[Arterial graft anastomosis in coronary surgery: side by side stitch with parachute technique].

We describe some techniques on arterial graft anastomosis that seem to be useful in coronary artery bypass. The graft is positioned with its cut surface upward, parallel to the left side of the coronary artery from surgeon's view point. The first stitch is placed from the inside of the coronary artery at the mid point of the anastomotic line adjacent to the graft. Then, a single stroke continuous sutures are carried out around the proximal corner of the anastomosis terminating at the one third point of the opposite side of the arteriotomy. After completion of this side by side stitch, the graft is approximated by pulling the suture in such a manner as parachute technique. The rest of the anastomosis can be performed in almost fore hand stroke. The time necessary for anastomosis is ten minutes at most.

Anastomosis, Surgical↗
PubMed1993

Cellular and humoral immune responses after fresh meniscal allografts in mice. A preliminary report.

To date, no study of allogeneic meniscal transplantation has investigated both the host cellular immune response and the humoral immune response. Using inbred mice, we examined cellular immunity to meniscal allografts by assaying mixed lymphocyte culture and investigated humoral immunity through a complement-dependent cytotoxicity test. The level of the stimulation index of the mixed lymphocyte culture seen after placing fresh meniscal allografts subcutaneously was not significantly higher than when isograft controls were similarly placed. Following placement of the allografts, no specific antibodies were detected in serum throughout the 24-week period after grafting. Thus, in mice, fresh meniscus apparently is not immunogenic. Our results tentatively suggest that a fresh allogeneic meniscus might be transplanted without any special treatment to decrease its immunogenicity.

Animals↗
PubMed1993

Arthroscopic and histologic evaluation of anterior cruciate ligaments reconstructed with the Leeds-Keio ligament.

In 62 of the patients who underwent anterior cruciate ligament (ACL) reconstruction with the Leeds-Keio (L-K) artificial ligament, we performed an arthroscopic second look and biopsy of the reconstructed ACL at 8-36 months postoperatively. Arthroscopic findings were classified into two groups according to the tautness of the ligament and the coverage of the implanted L-K ligament with synovial tissue. Histologic results were classified into three groups according to the orientation of the collagen fibers around the L-K ligament, and the arrangement and morphology of the cells. Although our results demonstrated that the implanted L-K ligament had the capacity for tissue induction, no statistically significant correlation was observed between any two results among the arthroscopic, histologic, and clinical data. Therefore, within the time span of our experiment, we could not conclude that the L-K ligament functioned as a scaffold type of artificial ligament. More convincing results must be attained before any firm recommendation can be made for the use of the L-K ligament as a substitute ACL over the autograft or allograft.

Adolescent↗
PubMed1993

[The amnioinfusion therapy of saline solution for premature rupture of the membranes before 27 weeks' gestational age].

Saline solution amnioinfusion was performed for 12 cases of preterm PROM before 27 weeks gestational age complicated by oligohydramnios in order to suppress chorioamnionitis, prevent fetal pulmonary hypoplasia and delay delivery. The results were as follows. 1. The mean gestational ages at diagnosis of premature rupture of membranes and initiating saline solution amnioinfusion were 23.6 +/- 2.9 weeks and 24.9 +/- 1.5 weeks, respectively. The mean duration of saline solution amnioinfusion was 14.7 +/- 11.9 days. The mean gestational age at delivery was 27.2 +/- 1.7 weeks. The mean birth weight was 1,056 +/- 220g. 2. Saline solution amnioinfusion was effective in relieving oligohydramnios in all cases. No pulmonary hypoplasia was observed in the infants. 3. Clinically saline solution amnioinfusion was effective in suppressing chorioamnionitis in 9 cases out of 12. Histologically the picture of chorioamnionitis was revealed in 10 cases out of 12. no serious infection was observed in the infants. 4. Nine infants out of 12 survived. There were 2 IUFD and one neonatal death. The perinatal survival rate was 75%. 5. It is concluded from the above results that saline solution amnioinfusion is an effective treatment for preterm PROM before 27 weeks' gestational age.

Amnion↗
PubMed1993

[Malfunction of mitral and tricuspid Ionescu-Shiley pericardial xenografts].

We report a case of the malfunction of Ionescu-Shiley pericardial xenografts (ISPX) in the mitral and tricuspid positions at 6 years after implantation. The patient underwent an emergency operation successfully despite his high age (75 years) and extremely poor preoperative condition. The valve extracted from the mitral position showed spontaneous disruption of the leaflet, while the tricuspid valve graft was entangled with the preserved native septal leaflet around the stents. This former complication is now widely recognized, but the latter one appears to be rare. Care should be taken in replacing the atrioventricular valve with a bioprosthesis when the native valve leaflets are not removed. Although the ISPX is no longer in clinical use, careful follow-up is mandatory in patients with this prosthesis especially when it was implanted in the mitral position.

Aged↗
PubMed1992

Intestinal type alkaline phosphatase hyperphosphatasemia associated with liver cirrhosis.

Hyperphosphatasemia due to increased intestinal type serum alkaline phosphatase was noted in a 48-year-old male who had asymptomatic liver cirrhosis. The alkaline phosphatase activity in the serum was 828 U/l (our reference range in adults: 57-194 U/l), 94% of which was of the intestinal type as measured by an immunoprecipitation method. The intestinal component of alkaline phosphatase was separated into two major and some minor components using electrophoresis and isoelectrofocusing. One of the major components had similar mobility to that of a standard intestinal enzyme purified from adult intestine. The components were heat-labile and neuraminidase-resistant. Serial lectin affinity chromatography, however, indicated that sugar chain compositions of the alkaline phosphatase were different from those of the standard tissue intestinal enzyme. These results and further enzymological studies suggest that the patient's serum alkaline phosphatase basically consisted of several intestine-like isoforms.

Alkaline Phosphatase↗
PubMed1992

Growth retardation due to idiopathic growth hormone deficiencies: MR findings in 24 patients.

In this study we evaluated the pituitary-hypothalamic abnormalities of "idiopathic growth hormone (GH) deficiency" as demonstrated by MR imaging. Twenty-four patients were examined with a 1.5-T unit using spin echo T-1 weighted images. The patients were divided into two groups according to MR findings: those with ectopic posterior pituitary glands (12 patients), and those with normal posterior pituitary glands (12 patients). Ten patients in the former group and four in the latter group had small anterior pituitary glands. All patients in the former group but only four in the latter group had severe GH deficiencies. Multiple hormone deficiencies were found in eight patients in the former group, but in only two in the latter group. Among the 12 patients with posterior pituitary ectopia, 11 were males, 10 had been born by breech delivery, and four had a history of asphyxia. It is speculated that perinatal abnormalities can cause posterior pituitary ectopia and that there is a close correlation between breech delivery and the male disadvantage of posterior pituitary ectopia. Half of our patients with "idiopathic GH deficiency" had ectopic posterior pituitaries. GH deficiency with posterior pituitary ectopia should no longer be considered idiopathic because organic lesions can now be identified during life.

Adolescent↗
PubMed1992

A device for tracheal tube during CO2 laser irradiation in laryngomicrosurgery.

We devised that the segment of commercially available defensor II tube coming in contact with the vocal cord was concaved. We used this new tube during CO(2) laser irradiation in laryngomicrosurgery. We came to the conclusion that it was much more superior to the conventional tube in safety and resistance of the material to Co(2) laser irradiation and in increase of the operation field.

Journal Article↗
PubMed1992

Experimental evidence of selective axonal regeneration in allogenic and isogenic Y-chambers.

Studies on axonal regeneration in Y-chambers over the past decade have consistently provided evidence of preferential growth toward a distal nerve piece. However, these findings are in contrast to the observations by Weiss and Taylor (1944. J. Exp. Zool. 95: 233-257), indicating that in fresh aortic Y-chambers regenerating axons had no tendency to grow into a channel containing a distal nerve piece as compared to an open channel. The discrepancy between Weiss and Taylor's findings and those of later authors remains unexplained. In the present study we repeated the investigations by Weiss and Taylor, using both isogenic and allogenic aortic Y-chambers. In control groups the aorta graft was frozen and treated chemically to kill all cells and to deactivate possible growth factors of protein nature. In these groups preferential growth toward the distal nerve was pronounced although such specificity in growth was evident also in the nontreated types of aortic chambers. The findings do not support the results presented by Weiss and Taylor.

Animals↗
PubMed1992

Reinnervation of denervated skeletal muscles by grafted dorsal root ganglion.

We examined whether or not the cervical dorsal root ganglion (DRG) of the rat, when isografted and connected to the distal stump of the severed common peroneal nerve, could survive, project axons to the denervated leg muscles, and exert beneficial influences to delay the degeneration of the denervated muscles. Rats in which the muscles were similarly denervated but no DRG was grafted served as the control. After a postoperative period of 72 to 286 days, histological study showed that nerve cells at the superficial part of the grafted DRG survived. Indirect electrical stimulation via the distal stump of the common peroneal nerve produced no contraction of the muscles, indicating that no functional neuromuscular contacts had been reestablished. Direct stimulation of the denervated muscles did elicit contraction, and the isometric twitch and tetanic tensions were significantly much higher in the experimental rats with a grafted DRG than in the control rats. Cholinesterase-silver staining indicated the presence of axons in the denervated muscles, but the axons did not terminate on endplates. Compared with the control muscles, the experimental muscles had significantly more axons, and had atrophied less as indicated by muscle wet weight and histological appearance. These results indicate that the sensory axons can delay the weakening and atrophy of muscles after denervation. We suggest that the sensory axons may exert certain trophic influence on the denervated muscle fibers, though the actual mechanism is unknown.

Animals↗
PubMed1991

[Computed tomographic features in ovarian bleeding].

CT scans of eight patients with ovarian bleeding (7 idiopathic and 1 secondary to bleeding tendency) were reviewed. CT showed intrapelvic hemorrhage in all cases, and ruptured ovary was identified in 6 cases. High density area in or around the ovary, seen in 2 cases, suggested the site of bleeding. In 4 cases the ovary was observed as a low density area. Ovarian bleeding is a common disorder, and should be considered as a differential diagnosis of intrapelvic hemorrhage in females.

Adult↗
PubMed1991

Magnetic resonance imaging of cerebral fat embolism.

The cerebral fat embolism is a potentially serious complication of fractures but clinical cases often go undiagnosed. Two cases of clinically diagnosed cerebral fat embolism are reported, and MR images of these patients are described. While brain CT revealed no abnormality, MR imaging showed relative low-intensity areas on T1-weighted images and high-intensity areas on T2-weighted images. In one patient follow-up MR showed nearly complete resolution of the abnormal signal. MR imaging appears to be valuable for detecting the lesions in these patients.

Adolescent↗