Biomedical subjects

S Hitomi

Publications and source records attributed to S Hitomi.

At least 91 records · Page 5Linked to original sources

PubMed1996

Ultrastructural changes in canine lung preserved in newly developed solutions.

The present study was undertaken to clarify the effect of differences in the ionic composition of a preservation solution by investigating ultrastructures of pulmonary endothelial cells and oxygenation ability of preserved lungs after reperfusion. The relation between the ultrastructural changes and the oxygenation ability was also examined. Canine lungs flushed with an extracellular-type (ET)-Kyoto solution (group A, n = 6), with an intracellular-type-Kyoto solution and prostaglandin El (group B, n=6), or with Euro-Collins solution and prostaglandin E1 (group C, n=6) were stored at 4 degrees C for 20 hr. In transmission electron microscopic findings, the frequency of ultrastructural changes (protrusion of endothelial cells and cellular vacuolization) was significantly less in group A (23.3 +/- 9.1 and 13.3 +/- 5.2%, respectively) than in group B (64.4 +/- 6.1 and 42.2 +/- 8.8%, respectively). In group A, PaO2 after 40, 70, and 130 min of reperfusion was uniformly excellent (289.4 +/- 5.7, 303.3 +/- 7.0, and 303.0 +/- 19.6 mm Hg, respectively) and significantly higher than in groups B and C (202.6 +/- 32.0 and 185.9 +/- 23.0 mm Hg, respectively) after 70 min and higher than in group C (155.7 +/- 36.3 mm Hg) after 130 min of reperfusion. A negative correlation was noted between the frequency of cellular vacuolization and the PaO2 after reperfusion. These results indicated that extracellular ion composition has significantly better effect on pulmonary vascular ultrastructures than intracellular ion composition. This may be a factor making ET-Kyoto solution superior to the other two solutions in oxygenation ability after reperfusion. When attempting to develop better lung preservation solution, the ability to preserve the ultrastructures of preserved lung may be an important consideration in the evaluation.

Animals↗

PubMed1996

Resection of primary pulmonary hemangiopericytoma: a report of two cases.

We report herein the cases of two patients who underwent resection of a primary pulmonary hemangiopericytoma. The first patient was a 58-year-old man found to have a mass-like shadow of about 5 cm in diameter in the right hilum by a routine chest X-ray. Subsequent magnetic resonance imaging (MRI) showed a probable mediastinal tumor, and surgery was performed. Postoperative pathological examinations confirmed the diagnosis of pulmonary hemangiopericytoma. The second patient was a 21-year-old woman found to have a mass-like shadow of about 2 cm in diameter in the left middle lung field. As a preoperative diagnosis could not be made, exploratory surgery was performed and the left S6 segment was excised. A definitive diagnosis of pulmonary hemangiopericytoma was established postoperatively by pathological examination. Primary pulmonary hemangiopericytoma is an extremely rare type of tumor, with only 36 cases having been reported in the Japanese literature to date, including out 2 cases. A discussion following the case reports examines the sex, age, initial manifestations, sites, and methods of surgery employed in these 36 cases.

Adult↗

PubMed1996

The infeasibility of using ten-ring irradiated grafts for tracheal allotransplantation even with omentopexy.

In our previous study, we demonstrated that high-dose 60Co irradiation was able to prevent rejection of canine tracheal allografts. To determine the maximum possible length of these grafts, in the present study we attempted to transplant five-ring and ten-ring tracheal allografts in two groups of five dogs each. Either five or ten rings were excised from donor tracheas and irradiated with 100,000 cGy of 60Co. The irradiated tracheal grafts were transplanted to replace either five- or ten-ring sections of the mediastinal tracheas removed from the recipient dogs. The grafts were covered with omental pedicles and no immunosuppressants were used. Graft incorporation was achieved in four of the five dogs in the five-ring groups, and three of these dogs survived for more than 700 days. However, four of the five animals in the ten-ring group died from tracheostenosis accompanied by ischemia within 3 weeks. These findings demonstrate the impossibility of performing ten-ring tracheal allotransplantation using irradiated grafts, even with omentopexy.

Animals↗

PubMed1996

Surgical treatment for invasive thymoma, especially when the superior vena cava is invaded.

BACKGROUND: We analyzed the operative outcome of extensive surgery for invasive thymoma, especially in those with thymomas invading the superior vena cava, the left innominate vein, or both. METHODS: We treated 41 patients with invasive thymoma, including 34 stage III, 5 stage IVa, and 2 stage IVb thymomas. Thirty-eight patients received radiotherapy preoperatively or postoperatively. In 12 patients with invasion of the superior vena cava or innominate vein, we performed angioplasty, reconstruction, or both. RESULTS: The overall 5-year survival rate was 77% and the 10-year survival rate was 59%. In the stage III group, there was a significant difference between those with complete and those with incomplete resection. Ten of 12 patients who had angioplasty with or without reconstruction of the superior vena cava or innominate vein survived without recurrence of the tumors. CONCLUSION: Angioplasty and vascular reconstruction are recommended because successful treatment for invasive thymomas depends on complete resection of the tumors.

Adolescent↗

PubMed1996

Trehalose-containing solutions enhance preservation of cultured endothelial cells.

BACKGROUND AND METHODS: We have developed two types of preservation solutions containing trehalose. ET-Kyoto solution (ET-K) is an extracellular type and IT-Kyoto solution (IT-K) is an intracellular type. In the present study we examined with in vitro assays the ability of ET-K, IT-K, Euro-Collins (EC), and University of Wisconsin (UW) solutions to preserve a murine endothelial cell line. The viability of cells stored in the solutions at 4 degrees C was determined by trypan blue exclusion and MTT assay. RESULTS: Trypan blue exclusion showed the viability after 48 hours of cold storage to be 49.5 +/- 4.7% (mean +/- standard error) in ET-K, 59.5 +/- 0.7% in IT-K, 29.2 +/- 2.5% in EC, and 55.3 +/- 7.6% in UW (ET-K or UW versus EC, p < 0.05; IT-K versus EC, p < 0.01). MTT assay absorbance values for cells after 48 hours of cold storage were 0.366 +/- 0.0066 (mean +/- standard error) in ET-K, 0.358 +/- 0.0044 in IT-K, 0.336 +/- 0.011 in EC, and 0.362 +/- 0.0019 in UW (ET-K or UW versus EC, p < 0.05). After 120 hours, absorbance values for cells were 0.303 +/- 0.0038 in ET-K, 0.269 +/- 0.0034 in IT-K, 0.186 +/- 0.011 in EC, and 0.265 +/- 0.0066 in UW (ET-K versus UW, p < 0.05; ET-K versus IT-K, p < 0.01; ET-K, IT-K or UW versus EC, p < 0.01). CONCLUSIONS: As far as the ability to preserve a murine endothelial cell line at a low temperature was concerned, the ET-K solution was superior to the UW solution, the IT-K solution and UW solution were equal, and the ET-K and IT-K solutions were superior to the EC solution.

Animals↗

PubMed1996

ET-Kyoto solution for 48-hour canine lung preservation.

BACKGROUND: ET-Kyoto (ET-K) solution, proven safe for 20-hour lung preservation, was modified to achieve longer preservation: ET-K2 solution with more buffer capacity and ET-K3 with less potassium. METHODS: Lungs were preserved with one of the three solutions (with prostaglandin E1 at 4 degrees C for 48 hours (n = 5 for each). Left lung transplantation was performed and evaluated for 6 hours. RESULTS: Each solution became acidic after preservation (p < 0.01), though the change was lowest in the ET-K2 solution. All animals in the ET-K and ET-K3 groups survived for 6 hours after reperfusion, but only 1 survived in the ET-K2 group (p < 0.05). In all groups, partial pressure of oxygen in arterial blood decreased gradually after reperfusion. Pulmonary vascular resistance after reperfusion was significantly lower in the ET-K group than in the ET-K3 group (p < 0.01). Scanning electron microscopic examination showed that endothelial cell swelling and disruption were milder in the ET-K group (with the solution containing potassium of 44 mEq/L) than in the ET-K3 group. CONCLUSION: Lung preservation can be achieved for 48 hours in ET-K and ET-K3 solutions. Enhancement of buffer capacity provides no advantage. Potassium at 44 mEq/L does not cause deterioration of endothelial cells.

Animals↗

PubMed1996

A newly developed solution enhances thirty-hour preservation in a canine lung transplantation model.

Ischemia and reperfusion cause the production of oxygen free radicals. These damage grafts or disrupt normal vascular homeostatic mechanisms, with a parallel reduction in endothelial nitric oxide and adenosine 3',5'-cyclic monophosphate levels. We hypothesized that lung preservation failure may be related to these events. To improve lung preservation, we prepared a new ET-Kyoto solution, which contains N-acetylcysteine (a radical scavenger), nitroglycerin (to elevate the nitric oxide level), and dibutyryl adenosine 3',5'-cyclic monophosphate (to elevate the adenosine 3',5'-cyclic monophosphate level) and examined its efficacy in a canine single-lung transplantation model. Lungs were flushed with new ET-Kyoto solution (group I, n = 9), basal ET-Kyoto solution (group II, n = 6), basal ET-Kyoto solution plus ethanol and propylene glycol (solvents of nitroglycerin; group III, n = 6), or low-potassium dextran glucose solution (group IV, n = 6), and stored at 4 degrees C for 30 hours. After left single-lung transplantation, the right main bronchus and right pulmonary artery were ligated and the functions of the transplanted lung were assessed for 6 hours. Arterial oxygen tension was significantly higher in group I than in groups II, III, and IV (p < 0.05). Peak inspiratory pressure and wet-to-dry lung weight ratio were significantly lower in group I than in groups II and IV (p < 0.01). Histologic and ultrastructural studies showed better preservation in group I than in groups II, III, and IV. We conclude that the new ET-Kyoto solution provides enhanced 30-hour lung preservation.

Animals↗

PubMed1996

Split transplantation of the trachea: a new operative procedure for extended tracheal resection.

Before tracheal transplantation can be applied clinically, several problems must be solved: immunosuppression, blood supply to grafts, and reliable long-term preservation of grafts. We have conducted experiments on tracheal transplantation to solve these problems. In the present study, we tried a new operative procedure to accomplish reliable revascularization of transplanted tracheal grafts. It has been reported that transplantation of a 10-ring length of trachea is difficult even with omentopexy. Long tracheal allografts can be transplanted with use of direct revascularization, but this technique is extremely troublesome. Thus we developed a new operative procedure, "split tracheal transplantation," in which grafts are divided at the midportion and covered with omentum, after demonstrating that the blood supply to tracheal grafts can be reestablished around the suture lines. Two groups of dogs were used. In group A (control, n = 4), a 10-ring length of trachea was autotransplanted. The anastomotic sites and grafts were covered with omental pedicles. In group B (split tracheal transplantation, n = 10), tracheal grafts 10 rings long were autotransplanted. These grafts were divided at the midportion, a piece of omentum was inserted between the two halves, and the midportion was sutured. Grafts were observed regularly by bronchoscopy and examined histopathologically after the animals died or were killed. In some animals, microangiography of the bronchial circulation was done. In the control group, necrosis, stenosis, or malacia of the grafts was observed in three of the four animals. In the split transplantation group, all animals survived for at least 2 months, all grafts were incorporated, and none showed ischemia, stenosis, or malacia. Microscopic examination and microangiography revealed that neovascularization of the graft was promoted by omentum inserted at the midportion of the graft. Split transplantation of the trachea is an easy and reliable way to extend tracheal resection.

Anastomosis, Surgical↗

PubMed1996

Time trends and survival after operations for primary lung cancer from 1976 through 1990.

To assess the time trends and survivals after operations for primary lung cancer, the cases of 845 consecutive patients who underwent thoracotomy between 1976 and 1990 were retrospectively reviewed by groups corresponding to year of the operation (the early period was 1976 to 1980, n = 208; the middle period was 1981 to 1985, n = 291, and the late period was 1986 to 1990, n = 346). The 5-year survivals at the early, the middle, and the late periods were 31.5%, 39.0%, and 54.0%, respectively, with significant improvement particularly at the late period (p < 0.05 for the early period vs the middle period, p < 0.01 for the early or middle period vs the late period); the improvement was caused by increase in the ratio of patients with stage I disease (20.7% at the early period, 32.0% at the middle period, 44.2% at the late period), increase in the rates of complete tumor resection with lymph node dissection (57.2%, 68.0%, 74.3%, respectively), and decrease in the rates of operation-related death (3.8%, 3.4%, 0.9%, respectively). The postoperative prognosis of patients with stage II disease at the late period (5-year survival 74.8%) showed significant improvement compared with the other periods. Moreover, the prognosis of patients with stage IIIa, pN2 disease (5-year survival 41.5%) showed significant improvement, which was caused by the significant decrease in patients with pT3 N2 M0 disease and poor prognosis.

Adenocarcinoma↗

PubMed1996

Long-term cryopreservation can prevent rejection of canine tracheal allografts with preservation of graft viability.

We previously reported that cryopreservation of tracheas for 1 month was possible in a canine tracheal autotransplantation model with use of a preservative solution containing trehalose. Realizing that the allogenicity of many organs is decreased by freezing, we examined the possibility of immunosuppressant-free canine tracheal allotransplantation after long-term cryopreservation. Six to 10 rings of the trachea were removed from donor dogs (n = 12), immersed in the preservative solution, and cryopreserved in a deep freezer at -85 degrees C for 285 +/- 28 days (cryopreservation group). Five rings of the mediastinal trachea of recipient dogs were removed. The cryopreserved tracheas were thawed and transplanted to replace the excised mediastinal tracheas. In a control group (n = 6), the graft was preserved in Euro-Collins solution at 10 degrees C for 16 to 17 hours. Allotransplantation of tracheas was done as in the cryopreservation group. The anastomotic site and graft were covered with an omental pedicle in both groups. In the cryopreservation group, every animal, except one that was killed for pathologic examination, survived more than 2 months. All the grafts of this group were viable, and no stenosis or tracheomalacia was observed. In the control group, most of the animals died within 1 month of tracheal stenosis caused by rejection. These findings reveal that immunosuppressant-free canine tracheal allotransplantation was consistently possible after long-term cryopreservation of the graft in a preservative solution containing trehalose. This simple method could solve both donor shortage and immunosuppression problems.

Animals↗

PubMed1996

Extensive resection with selective cerebral perfusion for a lung cancer invading the aortic arch.

An extensive operation for lung cancer invading the aortic arch is reported. A 66-year-old man presented the recent onset of hoarseness. Chest computed tomography and magnetic resonance imaging demonstrated a tumor of the Botallo lymph node invading the aortic arch. Left pneumonectomy with combined resection of the aortic arch was performed with the use of brain-isolated cardiopulmonary bypass. The aortic arch was resected and replaced by an artificial graft. Pathological examination revealed a primary lesion of adenocarcinoma in the left upper lobe and contiguous lymph node involvement, pT4N2M0. He was discharged and followed as an outpatient, however he died of miswallowing 10 months later. Such an extensive operation may be of value in selected patients.

Adenocarcinoma↗

PubMed1996

A case of giant cell tumor of the rib with magnetic resonance imaging.

A surgical case of giant cell tumor originating from the right seventh rib in a 51-year-old Japanese man is reported. Surgical resection without radiation therapy is preferable, because radiation may cause malignant transformation of this kind of tumor. Magnetic resonance imaging (MRI) of the tumor, reported for the first time in the English literature, was useful in planning complete resection, because both the excellent soft-tissue contrast resolution and the multiplanar images could demonstrate accurately the tumor extent both in the bone marrow and to the surrounding soft tissue.

Bone Neoplasms↗

PubMed1996

Intercostal hemangioma.

Chest wall tumors are uncommon and there have been only a few reports of intercostal hemangioma during the past 20 years. We treated a 33-year-old man who presented with intercostal hemangioma. We resected tumor and surrounding muscles beyond the limits of the lesion without removing any bone or lung tissue. The patient is free of any recurrence 3 years after surgery.

Adult↗

PubMed1996

Oral sustained-release cisplatin capsule.

An oral sustained-release cisplatin preparation was prepared by combining microporous water-insoluble pharmaceutical polymer, ethylcellulose, a membrane and a gel-forming polymer, poly(acrylic) acid (Carbopol). As cisplatin is an extremely hydrophilic and small compound, it was difficult to control the release rate solely by the micropores on the ethylcellulose capsule. To retain cisplatin within the capsule, gel-forming polymer was formulated inside the capsule. The release rate of cisplatin was dependent both on the number of micropores of the capsule and the formulated amount of Carbopol. The number of micropores ranged from 20 and 30 to 60, and the formulated amount of Carbopol varied from 15 to 100 mg. In-vitro release experiments suggested that the release rate decreased as the formulated amount of Carbopol increased when the pore number was 60 and 30. However, when pore number was decreased to 20, the effect of the amount of Carbopol was not clearly observed. In the in-vivo study using rabbits, the sustained-release cisplatin capsule was evaluated in comparison with solution after oral administration of 20 mg drug. With the pore number of 60, Cmax was 0.46 +/- 0.02 microgram mL-1 at 4 h and thereafter serum concentrations declined rapidly. When the pore number was 30, serum cisplatin level-time profiles showed long-acting patterns and AUC was reversely correlated with the formulated amount of Carbopol. Cmax and tmax were 0.41 +/- 0.02 microgram mL-1 and 3.33 +/- 0.88 h, respectively and 0.23 +/- 0.01 microgram mL-1 was obtained at 24 h after oral administration of capsule having 30 pores and 15 mg of Carbopol. We conclude that the possibility of developing an oral sustained-release cisplatin preparation is feasible.

Acrylic Resins↗

PubMed1996

Adjuvant chemotherapy after complete resection in non-small-cell lung cancer. West Japan Study Group for Lung Cancer Surgery.

PURPOSE: We performed a study to determine whether postoperative mild chemotherapy to maintain the patient's quality of life (QOL) and immunoactivity could also prolong survival. SUBJECT AND METHODS: From December 1985 to July 1988, 323 patients with completely resected primary non-small-cell lung cancer (stage I to III) were enrolled. The subjects were randomized into three treatment groups, as follows: cisplatin (CDDP) 50 mg/m2 body surface, vindesine (VDS) 2 to 3 mg/kg body weight for three courses, and 1-year oral administration of tegafur (FT) plus uracil (UFT) 400 mg/kg body weight (CVUft group, 115 patients); 1-year oral administration of UFT 400 mg/kg body weight (Uft group, 108 patients); or surgical treatment only (control group, 100 patients). RESULTS: The overall 5-year survival rates were 60.6% for the CVUft group and 64.1% for the Uft group versus 49.0% for the control group. The results of statistical testing were P = .053 (log-rank test) and P = .044 (generalized Wilcoxon test) among the three groups, P = .083 (log-rank) and P = .074 (Wilcoxon) between the CVUft and the control groups, and P = .022 (log-rank) and P = .019 (Wilcoxon) between the Uft and the control groups, which indicates higher survival rates in the CVUft and the Uft groups compared with the control group. A multivariate statistical analysis on prognostic factors using Cox's proportional hazards model was performed with the following results: P = .037, hazards ratio = 0.64 with a 95% confidence interval (CI) of 0.42 to 0.97 (control v CVUft group); and P = .009, hazards ratio = 0.55 with a 95% CI of 0.36 to 0.86 (control v Uft group). CONCLUSION: Significantly favorable results were obtained in the CVUft and Uft groups compared with surgery alone. These data showed significant prognostic advantages in the postoperative adjuvant chemotherapy groups.

Adolescent↗

PubMed1996

Development of an ultrathin fiberscope with a built-in channel for bronchoscopy in infants.

Flexible fiberoptic bronchoscopy (FFB) is of great importance for diagnostic and therapeutic purposes in pediatric respiratory management. However, lack of a built-in channel in commercially available ultrathin fiberscopes has limited its usefulness in neonates and infants. Bronchoscopic procedures, including suctioning, BAL, bronchography, and selective drug injection have instead been performed by temporary extubation followed by mask ventilation. However, such techniques are not suitable for repeated FFB and are open to considerable risks, especially in critically ill patients. In this context, we developed a directable ultrathin fiberscope with an external diameter of 2.7 mm and a 0.8-mm internal diameter built-in channel. This prototype fiberscope, the XPF27, is useful during spontaneous ventilation and can be inserted through a 3.5-mm or larger endotracheal tube. The XPF27 was utilized for 55 FFB procedures and allowed suctioning, BAL, bronchial toileting, and bronchography in 16 critically ill children without complications. We conclude that XPF27 is useful for pediatric FFB despite its limited flexibility, visual field, and resolution.

Bronchoscopes↗

PubMed1996

Perineuronal sulfated proteoglycans, cell surface glycoproteins and dark neurons in the cingulate cortex of newborn and adult rats.

Many neurons in the adult rat cingulate cortex possess perineuronal sulfated proteoglycans detectable with cationic iron colloid and aldehyde fuchsin, or cell surface glycoproteins reactive to lectin Vicia villosa or soybean agglutinin. The perineuronal sulfated proteoglycans develop three to four weeks after birth. The cell surface glycoproteins develop at earlier stage or two to three weeks after birth. Dark or active neurons begin to appear three to four weeks after birth. These findings indicate that the brain matures after birth or during weaning period.

Animals↗

PubMed1996

Perineuronal sulfated proteoglycans in the adult rat brain: histochemical and electron microscopic studies.

Neurons of cerebellar nuclei in the rat brain had a marked surface coat which was stained with cationic iron colloid or aldehyde fuchsin. Neurons with a similar surface coat were also noted in the retrosplenial cortex. The surface coat was stained doubly with cationic iron colloid and aldehyde fuchsin. Digestion with hyaluronidase eliminated the stainability of the surface coat to both agents. Combined digestion with chondroitinase ABC, heparitinase and keratanase eliminated the cationic iron colloid staining but did not interfere with the aldehyde fuchsin staining. Electron microscopy of ultrathin sections revealed that the iron particles were deposited in the perineuronal tissue spaces. These findings indicate that the surface coat consists of sulfated proteoglycans which occupy, as the extracellular matrix, the perineuronal tissue spaces. Many neurons in the retrosplenial cortex were labeled with lectin Vicia villosa agglutinin. Double staining revealed that these lectin-labeled neurons are usually reactive to cationic iron colloid. Few neurons in the cerebellar nuclei were labeled with lectin V. villosa agglutinin.

Animals↗