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Biomedical subjects

S Kamata

Publications and source records attributed to S Kamata.

At least 91 records · Page 5Linked to original sources

Selective optical sensing of silver ions in drinking water.

A new thiocarbamate derivative is used in polymeric sensing films together with a lipophilic chromoionophore for determining Ag+ at submicromolar levels. The membrane composition has been optimized with a view to measuring concentrations of Ag+ added as a bacteriostatic agent to drinking water. The results compare well with those obtained by ICPMS.

Indicators and Reagents↗

Continuous monitoring of short-latency somatosensory evoked potentials during cardiac and aortic surgery.

The effectiveness of monitoring somatosensory evoked potentials (SEPs) intraoperatively to detect brain damage early remains controversial. To assess the diagnostic accuracy of this modality, a study was conducted between 1991 and 1994, recording SEPs in 287 consecutive patients undergoing cardiac and aortic surgery using cardiopulmonary bypass (CPB) with moderate hypothermia or deep hypothermic circulatory arrest. From P1 to N2 of the SEPs occurring within 50 ms latency in response to electrical stimulation of the median nerve were recorded over the contralateral postcentral cortex at 5-min intervals using a Neuropack-2 (Nihon Koden, Tokyo, Japan). Normal SEPs were recovered in 247 patients postoperatively; however, 2 of these patients had suffered a cerebral infarction and 1, a transient stroke intraoperatively, demonstrating a false-negative incidence of 1.2%. On the other hand, three different types of abnormal SEPs were recorded postoperatively. P1 and N1 absence, probably caused by a subcortical lesion, was observed in 4 patients; P2 and N2 absence, probably caused by a cortical lesion, was observed in 8 patients; and a flat SEP, representing diffuse damage, was observed in 2 patients. Among these 14 patients with abnormal SEPs, 7 showed no neurologic disturbance at all, demonstrating a false-positive incidence of 50%. Thus, we concluded that when normal SEPs are recovered during weaning from CPB, the incidence of brain damage could be predicted at below 5%. Conversely, when abnormal SEPs are demonstrated, the incidence of brain dysfunction impeding a return to active life is estimated to be about 70%.

Adolescent↗

Influence of glutamine-supplemented parenteral nutrition on intestinal amino acid metabolism in rats after small bowel resection.

Glutamine (Gln)-supplemented total parenteral nutrition (TPN) has been shown to improve mucosal adaptation after massive small bowel resection (SBR); however, its influences on intestinal amino acid metabolism remain unknown. In this study, intestinal amino acid flux, circulating plasma aminogram, mucosal glutaminase activity and protein, and DNA content were measured 7 days after massive SBR in rats receiving either standard (Std) or Gln-supplemented TPN. Sham-operated rats and rats fed chow after enterectomy served as controls. The uptake of Gln and the release of citrulline (Cit) by the remaining intestine was significantly decreased, with reduced mucosal glutaminase activity after SBR in the Chow and Std-TPN groups. Glutamine supplementation resulted in significantly increased gut Gln uptake compared with Std-TPN (P < 0.01). Mucosal glutaminase activity, mucosal protein, and DNA content was also increased by Gln; however, the gut release of Cit remained unchanged (P > 0.05). The subsequent decrease in circulating arginine (Arg) in the Gln-TPN group compared with the Std-TPN group (P < 0.05) was attributed to an insufficient exogenous supply. These findings show that Gln-supplemented TPN improves mucosal growth and gut Gln uptake after SBR. However, the intestinal production of Cit, which remained low in both TPN groups, may lead to an insufficiency of endogenous Arg synthesis. Thus, both Gln and Arg may be essential amino acids after SBR.

Amino Acids↗

Analysis of results of surgery performed over a 20-year period on 500 patients with cancer of the thoracic esophagus.

This study was conducted to examine the long-term outcome of 500 patients who underwent surgery for cancer of the thoracic esophagus during the past 20 years. Favorable results were obtained with postoperative adjuvant radiation and chemotherapy and there were no surgical deaths in the last 5 years. The mortality rate decreased from 17% prior to 1980 to 5% between 1981 and 1993, this being most probably attributable to the decreased incidence of suture leakage. With respect to changes in surgical techniques, during the initial years we performed intrathoracic anastomosis, after which sternal manubrium resection with anterior mediastinal esophagogastrostomy was carried out. Subsequently, we invented a technique for performing esophagogastrostomy via the posterior mediastinum. The posterior mediastinum was selected as the most physiologic route, based on measurement of tissue oxygen tension. Using blood flow determinations obtained by laser-Doppler velocimetry, we concluded that the effectiveness of thicker gastric tubes was superior to that of thin tubes. Esophagogastrostomy was performed in a shallow field in the cervical region, with the anastomosis ultimately positioned in the superior mediastinum and covered with mediastinal pleura.

Anastomosis, Surgical↗

Congenital bilateral zygomatico-mandibular fusion with mandibular hypoplasia.

We report a very rare case of congenital bilateral zygomatico-mandibular fusion with mandibular hypoplasia. Soon after birth, the patient underwent tracheotomy because of upper airway obstruction. At the age of one and a half years, reconstruction of the temporomandibular joint and lengthening of the ramus with a costochondral graft were performed. Only a few cases of congenital bony syngnathia revealed in this case have been described in the literature.

Humans↗

Anomalies of the tracheobronchial tree in patients with esophageal atresia.

To examine associated anatomic anomalies of the tracheobronchial tree and structural abnormalities of the trachea, and their clinical consequences, bronchoscopic examination and follow-up studies were performed in 32 patients with esophageal atresia (EA) and tracheoesophageal fistula (TEF) over a 5-year period. To evaluate structural abnormalities of trachea, the ratio of circumferential length of cartilaginous trachea to circumferential length of membranous trachea (C:M ratio) was determined before surgical repair. In patients examined before and after surgical repair, the motion of the posterior tracheal wall was observed under spontaneous respiration. Fifteen of the 32 patients (47%) had abnormalities of the tracheobronchial tree such as ectopic right upper bronchus (12), congenital bronchial stenosis (4), and absence of the right upper bronchus (2). The C:M ratio of the 27 patients with EA (2.0 +/- 0.6) was significantly lower than that of controls (3.0 +/- 0.3); the ratio for the 10 cases with ectopic right upper bronchus (1.7 +/- 0.4) was significantly lower than that of other cases (2.2 +/- 0.5). The C:M ratio for the 12 patients who had atelectasis (1.7 +/- 0.3) was significantly lower than that of the 15 who did not have atelectasis (2.2 +/- 0.6). Of 24 infants, nine had bulging of the posterior tracheal wall synchronized with expiration, and their C:M ratio (1.8 +/- 0.2) was significantly lower than that of the 15 patients without bulging (2.2 +/- 0.6). These data show an association between anatomic anomalies of the tracheobronchial tree and structural abnormalities of the trachea in patients with EA. Because these abnormalities may be related to the occurrence of respiratory disorders such as tracheomalacia and atelectasis, early bronchoscopic examination, including measurement of the C:M ratio and observation of the motion of the posterior tracheal wall under spontaneous respiration, may be useful in the care of patients with EA.

Bronchi↗

Prenatal diagnosis of abdominal wall defects and their prognosis.

To determine whether associated anatomic features may be useful in predicting fetal prognosis, 43 fetuses who had ultrasonographic evaluation for abdominal wall defects during a 13-year period were reviewed. Thirty-one fetuses had omphalocele and were classified into three groups according to fetal ultrasonography results: ruptured omphalocele with exposed liver, giant omphalocele with exposed liver, and small omphalocele without liver herniation. Twelve fetuses had gastroschisis. Ten of the 12 fetuses with gastroschisis survived; one died in utero. Nine of the 12 with a small omphalocele survived. Ten of 12 fetuses with giant omphalocele survived, but six of the seven with ruptured omphalocele died of pulmonary hypoplasia and respiratory insufficiency. Ruptured omphalocele recognized in utero was accompanied by intrauterine growth retardation and liver herniation and frequently was associated with deformity of the spine, diaphragmatic defects, vesicointestinal fissure, and meningocele. These results indicated that, together with the deformity of the spine, rupture and absence of the covering membrane with an exposed liver (noted through fetal ultrasonography) may suggest a poor prognosis because of pulmonary hypoplasia.

Abdominal Muscles↗

Significant telomere reduction in human superficial transitional cell carcinoma.

OBJECTIVE: To investigate telomere reduction and telomerase activity in human transitional cell carcinomas (TCCs) of the bladder, using primary tissue preparations, and their relationship to the clinicopathological properties of the TCC. MATERIALS AND METHODS: Tumour tissues were obtained from 21 patients together with apparently normal urothelia as controls. The mean telomere length of each sample was determined using southern blot analysis with an oligonucleotide probe (TTAGGG)4 and telomerase activity was semi-quantified using a polymerase chain reaction based assay. RESULTS: The mean (SE) telomere length was 6.6 (0.7) kb in tumour tissues and 11.5 (0.4) kb in apparently normal urothelia adjacent to the tumour (P < 0.001). Furthermore, it was 8.9 (1.4) kb and 3.4 (0.9) kb in superficial and invasive tumours (P = 0.002), respectively. Telomerase activity was detected in all 13 of the tumour tissues examined, with no relationship to telomere reduction, while it was undetectable in any of the control tissues. CONCLUSIONS: In human TCCs, telomere length was reduced in tumour tissue, more so in superficial than in invasive tumours. Telomerase was detectable only in tumour tissues and its activity was unrelated to telomere reduction.

Adult↗

[The long-term effect and outcome of preoperative chemotherapy combined with radiation therapy for bladder cancer].

(BACKGROUND). The object of this study is to evaluate the efficacy of preoperative chemotherapy combined with radiation therapy for bladder cancer. (METHOD). A total of 44 patients with bladder cancer were treated by preoperative chemotherapy combined with radiation therapy between October, 1981 and December, 1986. Of the 44 patients, ranging in age from 40 to 82, with an average age of 65.8, 34 were male and 10 were female. Clinical stages included 4 patients in Ta, 25 in T1, 11 in T2, and 4 in T3. Each patient was treated twice with 15 gray of radiation to the small pelvic cavity and a chemotherapy combination of adriamycin, cis-platinum, tegaful, and peplomycin. The average observation time after the therapy was 83 month, with the maximum being 146 months. (RESULTS). Complete remission was included in 5 patients, partial remission in 27, and no change in 12. Thus, the overall effective rate was 72.8%. Operations, selected by the results of the preoperative therapy, included transurethral resection on 28 patients, transurethral fulguration on 2, partial cystectomy on 4, resection of tumor on 4, and total cystectomy on 3. Operations were not performed on 2 patients and not allowed on 1 patient. The outcome during the long-term follow-up included cancer related deaths in 4 patients, and death resulting from other disorders in 9. The 5-year survival rates for superficial and invasive bladder cancer were 92.4%, and 83.9%, respectively. The 10-year survival rates for superficial and invasive bladder cancer were also 92.4% and 83.9%, respectively. The 3-year and 5-year non-recurrence rates for superficial bladder cancer were 75.8%, and 66.9% respectively, according to the Kaplan-Meier method. On the other hand, the 3-year and 5-year non-recurrence rates for invasive bladder cancer were both 73.8%. During the follow-up between 9 and 11 years, 3 upper tract tumor were diagnosed (2 ureteral cancer, and 1 renal pelvic cancer). (CONCLUSION). We concluded that preoperative chemotherapy combined with radiation therapy may be effective for the treatment of bladder cancer.

Adult↗

[Relationship between pretreatment serum levels of prostate specific antigen and bone metastasis in prostate cancer].

We retrospectively reviewed pretreatment levels of serum prostate specific antigen (PSA) in 138 newly diagnosed, untreated patients with prostate adenocarcinoma to evaluate the usefulness of serum PSA levels to predict results of radionuclide bone scans. All of the 24 patients with serum PSA levels above 200 ng/ml showed positive bone scans whereas those with serum PSA levels below 10 ng/ml included only three cases (3/51, 5.1%) positive for bone metastasis. All of the three had poorly differentiated adenocarcinoma of the prostate. In conclusion, bone scans may not be necessary in the cases with serum PSA levels less than 10 ng/ml except for those with poorly differentiated adenocarcinoma.

Adenocarcinoma↗

[Recent advance in head and neck cancer surgery].

In order to remove a tumor radically, it is necessary to resect the tumor en-bloc together with surrounding normal tissues as much as possible. This results in a large tissue defect. Since the head and neck region has important functions for daily life such as respiration, speech, chewing, swallowing, the size of tissue defect directly affects post-operative functions and cosmetic results. Recently, the use of free flaps has made it possible to resect the advanced tumor which had been thought to be inoperable before. The introduction of free flaps has permitted reconstruction of the skull base, the nasopharynx, the mandible and the face. These were impossible to reconstruct with pedicled flaps such as delto-pectoral flap and pectoral major musculo-cutaneous flap. Therefore, the indication of reconstructive surgery has been remarkably enlarged for advanced head and neck cancer. We employed reconstructive surgery using free flaps for head and neck cancer in 1982, and, in August 1994, the number of patients operated on with free flaps reached 1,000. Through our experience of head and neck reconstructive surgery, we can conclude that the use of free flaps for the reconstruction in the head and neck region has permitted enlarging surgical indication for far advanced head and neck cancers. And the free flaps have made it possible to assure oral functions such as speech and chewing after reconstruction of the palate or the mandible. The use of free flaps has also decreased the incidence of postoperative complications such as fistula, infection, etc. It is incontestable that reconstructive surgery is indispensable for the treatment of head and neck cancer.

Adolescent↗

[Investigation of the actual conditions of hospital nurses working on three rotating shifts: questionnaire results of shift work schedules, feelings of sleep and fatigue, and depression].

These studies were performed to clarify (1) the actual conditions concerning rotating shift schedules of nurses in Japanese university and college hospitals and to evaluate (2) some aspects of the physical and mental health, and (3) sleep profile of hospital nurses working on counter-clockwise shift rotation. Two questionnaire surveys and the OSA sleep inventory (OSA) were carried out. The subjects in the study (1) were a total of 80 nursing directors in university and college hospitals. The questionnaire covered 4 categories, such as the schedule most frequently adopted and reasons for using the schedule. The questionnaires were returned by 67 directors (83.8%). The subjects in the study (2) were 189 nurses working on three-shift work schedules at Asahikawa Medical College Hospital. The items in the questionnaire covered 7 categories, as follows: 1) feeling of sleep after each shift (8 items); 2) feeling of fatigue after each shift (30 items); 3) physical symptoms; 4) inter-personal problems; 5) all the items on Zung's self-rating depression scale (SDS); 6) all the items on the Horne and Ostberg morningness-eveningness questionnaire; and 7) 24 items on the Maudsley personality inventory. The questionnaires were returned by 156 nurses (82.5%), whose mean age and duration of shift-work employment were 27.2 +/- 5.1 and 5.0 +/- 4.3 years (mean +/- SD), respectively. For 152 nurses (97.4%) of those returning the questionnaire, the working schedule consisted of 2 consecutive night shifts and 2 consecutive evening shifts, following a variable number of day shifts (rapid and counterclockwise shift rotation). The subjects in the study (3) were 8 healthy nurses working on above-mentioned three rotating shifts at the psychiatric ward of Asahikawa Medical College Hospital, whose mean age was 29.4 +/- 5.8 years (mean +/- SD). All the subjects recorded their sleep-logs and underwent OSA everyday for 30 consecutive days. Of the 240 OSA data, 95 data (16 after day shift, 17 after the 1st night shift, 16 after the 2nd night shift, 15 after the 1st evening shift, 16 after the 2nd evening shift, 15 after day off) were analyzed. In addition to five of sleep factors in the OSA analysis, we evaluated the global score (GS), which represents subjective global feeling of sleep. In the study (1), 47 of 66 hospitals (71.2%) adopted rapid and counterclockwise shift rotation. The results of study (2) were as follows: 1) After the first night shift (diurnal sleep), the sleep problems were worst, and the frequency of taking sleep-inducing drugs was highest (12.6%); 2) Feelings of fatigue were the highest level after each of the two night shifts; 3) SDS score was relatively high (57.8 +/- 8.1, mean +/- SD); 4) The older the nurse, the greater the aggravation of both sleep problems and fatigue; 5) Sleep problems after day shifts were worse and SDS score was higher in nurses classified as "nightowls" compared to those in nurses classified as "morning people"; and 6) There was no difference between introverts and extroverts in sleep problems, fatigue or SDS score. The results of study (3) were as follows: 1) In 3 of sleep factors (Sleepiness, Integrated sleep, sleep initiation) and GS, there were significant differences among each rotating shift schedule including day off; 2) The highest score in five of sleep factors and the highest GS were noted after the 2nd night shift (nocturnal sleep), and the lowest after the 1st night shift (diurnal sleep); and 3) The younger subjects (n = 4; mean age, 24.5 years) showed a higher GS compared with that of the older subjects (n = 4; mean age, 34.2 years).

Adult↗

[Clinical analysis of embolism with left atrial myxomas].

We conducted a retrospective analysis examining the relationship between the tumor quality and the occurrence of systemic embolization in 16 patients who underwent surgical excision of the left atrial myxoma. Systemic embolization occured in 10 patients (63%) before surgery, in 5 of whom embolic episodes were the first manifestation of the tumor. Cerebral infarction had developed in 7 patients, TIA in 2, myocardial infarction in 2, limb ischemia in 2, and multiple infarctions in the kidney, adrenal gland, spleen and bone marrow in one. A permanent deficit remained in 6 patients (60%). Myxoma was a lobulated and gelatinous type in 9 (90%) of these patients with embolization and a solid type only in one case. When the dignosis of the left atrial myxoma with soft and fragile quality is made by echocardiography, surgical excision should be performed without delay to prevent systemic embolization.

Adolescent↗

[Influence of aging on the unilateral and the contralateral amygdaloid kindling in rats].

To investigate the seizure susceptibility in the rat after the mature period, the unilateral (primary site, left) and the subsequent contralateral (secondary site, right) amygdaloid kindling were examined in 2-3-month-old (n = 12, group A), 12-month-old (n = 11, group B), and 18-month-old (n = 7, group C) male Sprague-Dawley rats. At both of the primary and the secondary sites, the number of stimulations required to produce a generalized convulsion with falling (stage 5) increased as the age progressed, and there was a significant difference in the number of stimulations to reach stage 5 between groups A and B, and between groups A and C. These findings suggest that the age-related retardation of the development of amygdaloid kindling reflects aging changes of synaptic transmission. On the other hand, positive transfer effect (a facilitory effect of the primary site amygdaloid kindling on the development of the secondary site amygdaloid kindling) was observed in all of the three groups. This results suggests that both in and after the mature period, the secondary site amygdaloid kindling in the rats utilizes proconvulsant neuroplastic changes in the brainstem that has been already established by the primary site amygdaloid kindling.

Aging↗

[Malignant fibrous histiocytoma of spermatic cord: a case report].

A 52-year-old man presented with a painful, gradually enlarging mass in the left inguinal region. An ultrasound examination demonstrated a lobulated, heterogenous tumor 6.0 x 4.0 x 3.0 cm in diameter, which separated from the left testis and epididymis. Radical inguinal orchiectomy with wide en bloc local resection was performed. Histologic diagnosis was a malignant fibrous histiocytoma (MFH) with a giant cell variant. The patient underwent postoperative regional irradiation and has been alive without metastasis and local recurrence 3 months after the operation. Among the 19 patients with MFH of spermatic cord reported in Japan, only two cases were of giant cell type of MFH including the present case.

Genital Neoplasms, Male↗

[Surgical treatment of aortic valve endocarditis associated with aortic root aneurysm and abscess].

Between Jan. 1979 and Mar. 1996, aortic root abscess and aneurysm were encountered in 10 (34.5%) of the 29 patients who underwent surgical treatment for the aortic valve endocarditis ; native valve endocarditis (NVE) in 8 and prosthetic valve endocarditis (PVE) in 2. Noncoronary sinus was involved in 8 (80%) of 10 patients, left coronary sinus destructed in one, and more than one sinus were involved in one. All patients underwent aortic valve replacement after repair of abscess or aneurysm with suture closure in 5, and patch closure in 3, and its resection in one. Aortic root reconstruction using a valved conduit was required for the repair of aortico-ventricular discontinuity followed debridement of the abscess cavity of almost entire annulus in one PVE patient who consequentry died of LOS and sepsis. There was no operative or postoperative death in the other patients, however, one female patient suddenly died 24 months after surgery. She underwent direct suture closure of left coronary sinus aneurysm and aortic valve replacement with a small-sized prosthetic valve. Suture dehiscence of the orifice of the aneurysm developed immediately after surgery. It is concluded that patch closure of aortic root aneurysm or abscess is recommended so as to avoid narrowing of left ventricular outflow tract and recurrence of aneurysm formation even if its orifice proved to be small.

Abscess↗

[Traumatic thoracic aortic rupture--diagnosis and surgical repair].

Fifteen cases of traumatic thoracic aortic rupture (TAR) were treated at St. Marianna University Hospital from December 1980 to July 1995. Causes of TAR were due to vehicle accidents in 14 patients and fall in one patient. On diagnosis, contrast-enhanced CT scan was routinely performed in the patients with blunt chest trauma associated with superior mediastinal widening, loss of the aortic knob or right shift of the trachea on the initial roentgenogram. When CT scan demonstrated specific signs for TAR, pseudoaneurysm formation and/or extravasation of the contrast dye, aortography was eliminated before operation. As a role, operation was performed on an emergency basis as soon as the diagnosis was confirmed. Four cases died due to intrapleural rupture before or immediately after thoracotomy. Nine (82%) of the 11 patients in whom operation was completed survived and are doing well. In one of the 4 patients who underwent operation with simple aortic cross-clamping; paraplegia developed after 30 minutes of spinal ischemia. Left heart bypass with the Bio-Pump without heparin or with an antithrombin agent, argatroban, was used in recent 6 patients. Use of left heart bypass with the Bio-Pump without anticoagulant or with argatroban appears to be promising as a safe adjunct in the repair of TAR, preventing fatal bleeding of other injured organs.

Adolescent↗

[Surgery for bone metastasis of testicular tumor: a case report].

A 31-year-old man was admitted to our hospital with the chief complaint of painful right scrotal swelling. Based on the diagnosis of right testicular tumor with multiple lung metastasis and L2 vertebral body metastasis, right high orchiectomy and three courses of chemotherapy (peplomycin, etoposide, CDDP) were performed. Histological diagnosis was teratocarcinoma. With the complete remission for lung metastasis and no change for bone metastasis, L2 spondylectomy and additional four courses of the same chemotherapy were performed. The patient has been free of the disease for 11 months after the spondylectomy.

Adult↗