Biomedical subjects

M Yagi

Publications and source records attributed to M Yagi.

At least 73 records · Page 4Linked to original sources

PubMed1999

Complications associated with enteral nutrition using catheter jejunostomy after esophagectomy.

The present study was conducted on 78 patients, encountered over a 7-year period, who had a catheter-feeding jejunostomy placed at the time of thoracoabdominal esophagectomy for esophageal cancer. A broad-based attachment of the jejunal wall to the peritoneum at the place of entry of the catheter was used. Enteral nutrition was begun an average of 10 days after the operation, the caloric content was increased gradually, and the mean duration was 69 days. There were three patients who suffered from local skin erosion at the site of catheter entry, and seven who developed diarrhea and/or a feeling of abdominal fullness, but none of the patients showed any signs of peritonitis or ileus. The morbidity rates related to enteral nutrients and placement of the catheter jejunostomy were 8.9% and 3.8%, respectively. These findings demonstrate that a broad-based attachment of the jejunal wall to the peritoneum at the place of entry of the catheter is useful for preventing leakage or twisting of the jejunum, and for reducing the incidence and severity of the complications of catheter jejunostomy feeding.

Catheterization↗

PubMed1999

Efficacy of the axially loaded pivot shift test for the diagnosis of a meniscal tear.

Although magnetic resonance imaging (MRI) has improved the diagnostic accuracy of meniscal pathology, the authors believe that physical examination remains essential to the evaluation of knee pathology. In this study, the diagnostic accuracy of five clinical tests for meniscal pathology was prospectively evaluated in 160 patients, who thereafter underwent arthroscopy. 69% (109 knees) of the knees tested had associated ACL deficiency. There were 144 meniscal lesions in 130 of the 160 knees which were examined. The sensitivity of the tests was lower than the specificity. Conventional tests such as McMurray and Apley tests showed a low accuracy rate of 45% and 28% respectively. The diagnostic value of the axially loaded pivot shift test was significantly higher, indicating that this remains a useful diagnostic aid.

Adolescent↗

PubMed1999

A clinical and molecular study of a patient with Simpson-Golabi-Behmel syndrome.

Simpson-Golabi-Behmel syndrome (SGBS) is one of the overgrowth syndromes. Microdeletions of the glypican-3 (GPC3) gene were described by Pilia et al. (1996). Glypican-3 encodes a putative extracellular proteoglycan which is expressed in embryonic mesodermal tissues and plays an important role in embryonal growth. We report a Japanese patient with SGBS who had a single base deletion in the exon 7 of the GPC3 gene. This is the first report of a single base deletion of the GPC3 gene.

Abnormalities, Multiple↗

PubMed1999

Role of PDGF B-chain and PDGF receptors in rat tubular regeneration after acute injury.

Various polypeptide growth factors are generally considered to be involved in the regulation of the nephrogenic process both after acute renal injury and during renal development. Because platelet-derived growth factor B-chain (PDGF-B) has been reported to be expressed in immature tubulus of the developing kidney, PDGF-B could play a role in the process of tubulogenesis. We examined the expression of PDGF-B and PDGF receptors alpha and beta and their localization in kidneys after ischemia/reperfusion injury. The mRNA expressions of PDGF-B, PDGFR-alpha, and PDGFR-beta were enhanced after injury. In the immunohistochemical analysis and/or in situ hybridization, PDGF-B and PDGFR-alpha, beta were expressed after reperfusion in the S3 segment of the proximal tubuli, where they were not expressed normally. The expressions of proliferating cell nuclear antigen and vimentin were concomitantly observed with PDGF-B and PDGFRs in the tubular cells of injured S3 segment at 48 hours after injury. Next, the inhibition of the PDGF-B/PDGFRs axis with either Trapidil or Ki6896, which was found to inhibit the phosphorylation of PDGFR-beta selectively, resulted in a rise of serum creatinine, higher mortality rate, abnormal regenerating process, and suppressed proliferation of tubular epithelial cells. These findings suggest that the PDGF-B/PDGFRs axis is involved in the proliferation of injured tubular cells and plays an important role in the regeneration of tubular cells from acute ischemic injury.

Animals↗

PubMed1999

Tracheal agenesis in a child who survived for 6 years.

The authors report on a child with tracheal agenesis who survived for 6 years and 10 months. A female infant was born with respiratory distress and an absence of audible cry. With mask ventilation, gastrostomy and division of the esophagus was performed just after birth. She was well ventilated with an endotracheal tube inserted through the cervical esophagostomy after thoracic esophageal banding. An accidental extubation caused her anoxic encephalopathy at 9 months of age. She had been alive without artificial ventilatory support until she died of acute esophageal bleeding.

Abnormalities, Multiple↗

PubMed1999

Use of a Palmaz stent for tracheomalacia: case report of an infant with esophageal atresia.

A male infant with congenital cardiac anomalies and esophageal atresia with tracheoesophageal fistula (EA-TEF) showed intractable respiratory symptoms after delayed primary repair of EA-TEF. Computed tomography demonstrated that the trachea was compressed by the enlarged aorta. Artificial ventilation was necessary even after aortopexy performed at 2 months of age. At 140 days of age, an expandable metallic stent (Palmaz stent) was inserted through a rigid bronchoscope into the trachea underfluoroscopic control. His respiratory status improved dramatically, and he was extubated in 18 hours. Although the follow-up period has been 9 months, the short-term result is satisfactory. The expandable metallic stent placement should be considered in patients with EA-TEF who show intractable respiratory symptoms caused by tracheomalacia.

Esophageal Atresia↗

PubMed1999

Cochlear gene transfer: round window versus cochleostomy inoculation.

Two possible approaches for cochlear gene transfer have been inoculation via the round window membrane and through a cochleostomy. The aim of this study was to determine which of the two is more effective. Using both approaches, normal-hearing and deafened guinea pigs were inoculated with adenovirus carrying the reporter gene lacZ. After 5 days, the animals were killed and the cochlear tissue was stained with X-gal. The distribution and intensity of staining was estimated by a score system developed to compare gene transfer results between animals. We found that gene transfer via the cochleostomy resulted in a better distribution throughout the cochlea and in higher staining intensity, due to more efficient transfection. Auditory brainstem response (ABR) results showed that neither virus inoculation through a cochleostomy nor through the round window membrane had a significant effect on the click-ABR threshold measured on day 5 following virus injection. Gene transfer via both approaches was also found to be more effective in deafened animals than in hearing animals.

Adenoviridae↗

PubMed1999

Use of robotic technology for diathrodial joint research.

Knowledge of diarthrodial joint mechanics and specific function of the ligaments are needed in order to understand injury mechanisms, improve surgical procedures and design better post-surgical rehabilitation protocols. To facilitate these needs, a robotic/universal force-moment sensor (UFS) testing system was developed to measure joint kinematics in multiple degree-of-freedom and the in situ forces in the ligaments. When operated in the position control mode, the testing system applies a known load to the intact joint while the motion and force data are recorded. After transection of a ligament, the recorded motion for the intact joint is repeated and new force and moment data is recorded by the UFS. Since the robot reproduces the identical initial position as well as path of joint motion before and after a ligament is transected, the in situ force in the ligament is the difference between the two sets of force and moment data. In force control mode, a known force is applied to the intact knee while the kinematics are recorded. After ligament transection, the same force is applied while the changes in kinematics are again recorded. Testing in this mode is similar to a clinical examination that diagnoses ligament injury. To date, this testing system has been used for experimental studies that examine the anterior cruciate ligament & posterior cruciate ligament of the knee and ligaments of the shoulder. A three-dimensional finite element model has also been constructed based on CT/MRI scans of a knee specimen and validated using data obtained with the testing system. Once in vivo kinematics (such as during gait analysis or throwing activities) are available, the robotic/UFS testing system can be programmed to reproduce these joint kinematics on young human cadaveric specimens in order to generate a database for in situ forces in the ligaments, or Ligament replacement grafts. With appropriate computational models, the stresses and strains in these tissues in vivo can also be determined. Potential applications of this combined approach include pre-operative surgical planning, improvement of surgical procedures as well as development of appropriate post-operative rehabilitation protocols.

Biomechanical Phenomena↗

PubMed1999

A study of therapy for pediatric hepatoblastoma: prevention and treatment of pulmonary metastasis.

Our results of treatment for pediatric hepatoblastoma are presented with special emphasis on pulmonary metastasis. The pulmonary metastasis rate of hepatoblastoma was 44% (11/25). In 19 patients with resected hepatoblastomas, the 5-year survival rate without pulmonary metastasis was 90% (9/10); while with pulmonary metastasis it was 22% (2/9). Six patients with unresected hepatoblastomas all died within 4 months regardless of chemotherapy and/or metastasis. To improve survival in patients with hepatoblastoma, preoperative or postoperative chemotherapy was thought to be essential for tumors extending over 2 hepatic segments and having predictable factors for pulmonary metastasis (large size or histological evidence of capsular invasion). A long-term multidisciplinary approach including hepatic lobectomy, current multiagent chemotherapy (including CDDP, THP-ADR), and partial pulmonary resection for localized lung areas with metastases would ultimately be needed.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1999

Sacrococcygeal teratoma: a series of 19 cases with long-term follow-up.

A series of 19 cases of sacrococcygeal teratoma (SCT) with follow-up of 5 to 25 years is presented. Twelve patients were neonates, age 0 to 26 days (5 immature teratomas and 7 mature teratomas, representing 3, 6, 2, and 1 Altman's type I, II, III, and IV tumors, respectively), four were infants, age 1 to 6 months (all mature teratomas, representing 1, 1, and 2 Altman's type I, II, and IV tumors), and 3 were children, age 1 to 4 years (all malignant teratomas, all Altman's IV tumors). Eight babies were delivered by elective caesarean section (CS). Though the mean gestational age at CS was 34.3 weeks in our series, we now believe that CS often must be performed earlier, depending on a tumor size or fetal condition. Eleven neonates and 4 infants were operated upon using a sacral approach in 10 and an abdominosacral approach in 5, and all survived. However, 4 patients had neurogenic bladder and were treated by urinary catheterization or vesicostomy for 2 to 5 years after surgery. Postoperative urogenital sequelae are seen in patients with a large tumor, urethral compression, urinary retention, or edema of the lower body. Malignant tumors usually had metastasized by the time of diagnosis, but the prognosis for outcome has been improved following surgery and combination chemotherapy.

Adolescent↗

PubMed1999

Functional ileus in neonates: Hirschsprung's disease-allied disorders versus meconium-related ileus.

Sixty-eight neonates with functional ileus were reviewed. Twelve required laparotomy; in seven, histological studies revealed decreased ganglia and ganglion cells of the myenteric plexus (MP) (Group A), and in five, MP was normal (Group B). In the remaining 56 cases, obstructive symptoms were relieved following conservative therapy (Group C). All Group A cases except one had normal birth weight, while Group B and C cases showed significantly lower birth weights. A marked caliber change of the small intestine and/or small-caliber distal intestine with meconium stagnation in the proximal intestine was commonly demonstrated at operation in Group A and B, or on contrast enema in Group C. Four Group A cases died of enteritis, and three survivors suffered from prolonged obstructive symptoms. The grade of histological abnormality of MP correlated with the clinical outcome. In Group B, three died of sepsis shortly after surgery, but two survivors have been free from symptoms. Group A can be categorized as Hirschsprung's disease-allied disorders (HAD). Group B and C can be categorized as meconium-related ileus (MRI). The similarity of the macroscopic findings of HAD and MRI, and the occurrence of MRI exclusively in low birth weight neonates, strongly suggest that functional immaturity of MP plays a role in the etiology of MRI.

Ganglia↗

PubMed1998

Structure and expression of the human septin gene HCDCREL-1.

Septins are a family of highly conserved filament-forming proteins that have been shown to mediate cytokinesis and cytoskeletal organization in fungi and Drosophila. The gene encoding the human septin family member HCDCREL-1 has been shown to be transcribed from a locus immediately adjacent to that of the platelet glycoprotein (GP) Ib b. The HCDCREL-1 gene possesses a non-consensus polyadenylation signal that apparently is not efficiently utilized, resulting in the expression of a readthrough transcript also containing the platelet GPIb beta coding region. As a first step in understanding the regulation and function of HCDCREL-1, we have analyzed the structure of this gene and characterized its expression in a variety of human cells. Our results indicate that the gene is expressed at high levels in platelets and neural tissue, and is transcriptionally complex.

Base Sequence↗

PubMed1998

Pyloric motor abnormality in patients with infantile hypertrophic pyloric stenosis.

There are no published data of manometric studies of pyloric motor function in patients with infantile hypertropic pyloric stenosis (IHPS). The present study attempted to examine the characteristics of motor abnormality of the pylorus in five children with IHPS. Using a transducer-built-in manometric catheter cannulated through the pylorus under fluoroscopy, the pressure in the pyloric canal was recorded continuously over 3 h during fasting. Clusters of high-amplitude spastic contractions of over 300 mmHg were recorded at intervals. The frequency was 1-3/min (mean 1.7 cpm) and the duration was 7-15 s. These periodic spastic contractions were suppressed temporarily for 20-30 min after intravenous injection of 0.01 mg/kg atropine. After pyloromyotomy, these spastic contractions decreased remarkably in amplitude, but there were no changes in frequency. It is concluded that the underlying motor abnormality observed in hypertrophied pyloric muscle is clusters of high-amplitude contractions, although more precise measurements of basal pyloric pressure are needed to explore the pathophysiology of IHPS in detail. The effect of pyloromyotomy may be related to the decrease in high-amplitude contractions.

Atropine↗

PubMed1998

Change in nitric oxide in humans due to application of a pneumatic tourniquet.

The nitric oxide profile produced by application of a pneumatic tourniquet was investigated in the plasma of 15 patients. Nitrite (NO2-) and nitrate (NO3-) plasma concentrations were measured simultaneously by high-performance liquid chromatography (HPLC). UV detection using the Griess reaction was done after the reduction of nitrate to nitrite. The plasma nitrate concentration 5 min after reperfusion was significantly higher than the concentrations before ischemia, immediately before reperfusion, and the next day. In contrast, there was no significant difference in the plasma nitrite concentrations before ischemia, immediately before reperfusion, 5 min after reperfusion, and the next day. These findings suggest that the generation of NO is important in ischemic reperfusion injury.

Adolescent↗

PubMed1998

Mechanisms underlying the antireflux effect of Nissen fundoplication in children.

BACKGROUND/PURPOSE: It is reported that the main mechanism responsible for gastroesophageal reflux (GER) is transient lower esophageal sphincter (LES) relaxation in children. However, the effect of Nissen fundoplication on transient LES relaxation has not been investigated in children. This study examined the effect of Nissen fundoplication on motor patterns of the LES in children with pathological GER. METHODS: Esophageal manometry and pH were recorded concurrently for 2 hours after administration of apple juice (10 mL/kg). In seven children documented to have pathological GER by prolonged esophageal pH monitoring (%time pH less than 4.0>5.0), studies were performed preoperatively and 1 to 3 months after surgery. RESULTS: Nissen fundoplication virtually eliminated reflux in all patients. Percentage of time pH was less than 4.0 reduced from 15+/-9 to 0+/-0. Basal LES pressure did not change significantly (pre, 21+/-10 mm Hg v post, 27+/-9 mm Hg). The number of transient LES relaxation reduced significantly from 13+/-4 to 7+/-7, and the mean nadir LES pressures during swallow-induced LES relaxation and transient LES relaxation increased significantly from 1+/-1 mm Hg to 13+/-5 mm Hg and from 0+/-0 mm Hg to 11+/-7 mm Hg, respectively. CONCLUSIONS: Our findings suggest the antireflux effects of Nissen fundoplication may be based on changes of LES motor patterns that result in incomplete LES relaxation and reduction of the number of transient LES relaxation.

Child↗

PubMed1998

Beneficial effects of a novel inhibitor of platelet-derived growth factor receptor autophosphorylation in the rat with mesangial proliferative glomerulonephritis.

1. Our original compound, Ki6896 ((4-t-butylphenyl)(4-[(6,7-dimethoxy-4-quinolyl) oxy]phenyl) methanone) strongly inhibited the autophosphorylation of platelet-derived growth factor (PDGF) beta-receptor (IC50=0.31 microM) and that of basic fibroblast growth factor receptor (IC50=3.1 microM), whereas it did not inhibit some other kinases. 2. The [3H]thymidine incorporation and the growth of mesangial cells under the stimulation of PDGF were inhibited by Ki6896 in a dose-dependent manner. 3. In the mesangial proliferative glomerulonephritis rats induced by anti-Thy-1 monoclonal antibody, glomerulosclerosis was ameliorated and the number of glomerular proliferating cells was decreased by the daily administration of Ki6896. However, the accumulation of type I collagen and fibronectin in the glomeruli was not suppressed by Ki6896.

3T3 Cells↗

PubMed1998

Risk factors for low birthweight in Japanese infants.

The purpose of our study was to identify risk factors for low birthweight (LBW; birthweight < 2500 g) in Japanese infants. The data was collected from questionnaires completed by the parents of 23132 infants who underwent a standardized well baby check-up for 1-month-old infants, conducted by the Fukuoka City Medical Association from 1987 to 1995. The following eight factors and their second-order interaction terms were examined as potential risk factors for LBW: maternal age at delivery, history of live-born LBW infant, history of abortion in previous pregnancies, maternal smoking, coffee and alcohol consumption during pregnancy, prenatal training and live birth order. The results of multiple logistic regression analysis showed that the following three factors and one interaction term significantly contributed to LBW: history of live born LBW infant, maternal smoking, live birth order and the interaction between maternal smoking and live birth order. The smoker-related risk for LBW was quite different in each of the three groups stratified by live birth order. Efforts should be made, for example, to increase the accessibility of early, high-quality prenatal care for the high-risk groups with previous LBW babies and to implement smoking intervention, ranging from specific medical procedures to broad-scale public health and health-related educational programs in schools.

Alcohol Drinking↗

PubMed1998

Long-term observation of glomerulonephritis induced by multiple injections with anti-Thy-1 antibody in rats.

Multiple injections with a mouse monoclonal anti-rat Thy-1 antibody (five times, at weekly intervals) induced marked glomerular sclerotic lesions which are characterized by adhesion of glomerular capillaries to Bowman's capsule and persistent proteinuria in rats. Abnormal production of type I collagen and increased accumulation of type IV collagen and fibronectin were observed in these glomeruli. The glomerular expression of mRNA for these matrix components and transforming growth factor-beta1 (TGF-beta1) were markedly increased at 4 days after the last injections with anti-Thy-1 antibody, but decreased to below the levels of control rats at 5 weeks. This may be down-regulation of mRNA in mesangial cells. The glomerular sclerotic lesions were not progressive but the process of glomerular healing seemed to be retarded. The proteinuria and the glomerular adhesion were irreversible.

Animals↗