Biomedical subjects

H Wada

Publications and source records attributed to H Wada.

At least 433 records · Page 24Linked to original sources

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

Evaluation of a new solution containing trehalose for twenty-hour canine lung preservation.

We examined the efficacy of two new preservation solutions containing trehalose--an extracellular type (ET-K) of solution and an intracellular type (IT-K) of solution--in relation to that of Euro-Collins (EC) solution in 20-h canine lung preservation. Canine lungs were flushed with one of the three solutions (n = 5 for each solution) after pretreatment with PGE1 (20 micrograms/kg) and were stored for 20 h at 4 degrees C. The left lungs were transplanted and evaluated to 6 h post transplant. In the ET-K group, the arterial oxygen tension after reperfusion was significantly higher than in the IT-K and EC groups. The pulmonary vascular resistance, wet/dry weight ratio, and histological evaluation of each transplanted lung in the ET-K group were also better than in the IT-K and EC groups. This indicates that ET-K solution is useful for 20-h preservation of canine lung grafts.

Analysis of Variance↗

PubMed1996

Molecular cloning and linkage analysis of the Japanese medaka fish complement Bf/C2 gene.

Evolutionary studies of complement factor B (Bf) and C2 in lower vertebrates have revealed the presence of the Bf/C2 common ancestor-like molecule in lamprey (cyclostome) and the Bf molecule encoded by the duplicated genes closely linked to the major histocompatibility complex (MHC) in Xenopus (amphibian). To further define when Bf/C2 gene duplication occurred and when linkage between the Bf/C2 gene and the MHC was established, we amplified the Bf/C2 sequences in teleost, the Japanese medaka (Oryzias latipes), by reverse transcription - polymerase chain reaction with primers corresponding to the common amino acid sequences shared by mammalian Bf and C2. Only a single molecular species has been amplified, and the corresponding cDNA clones were isolated from the liver cDNA library. The longest insert contained 2384 nucleotides with an open reading frame of 754 residues. The deduced amino acid sequence showed 33.6% and 34.1% overall identity with the human Bf and C2 sequences, respectively, hence this clone was named medaka Bf/C2. The single-copy medaka Bf/C2 gene had exactly the same exon-intron organization as the mammalian Bf and C2 genes, and spanned about 8 kilobases. The Bf/C2 locus was mapped to the close proximity (2.9 cM) of the superoxide dismutase locus on the linkage group XX by the use of a restriction site polymorphism between two inbred strains of the medaka.

Amino Acid Sequence↗

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

Effective 30-hour preservation of canine lungs with modified ET-Kyoto solution.

BACKGROUND: With the aim of developing a preservation solution that can preserve donor lungs reliably for a long time, we prepared a modified ET-Kyoto solution by adding N-acetylcysteine, nitroglycerin, and dibutyryl adenosine 3', 5'-cyclic phosphate to the previously reported ET-Kyoto solution, which contains trehalose, gluconate, and hydroxyethyl starch. In this study, we examined the efficacy of modified ET-Kyoto solution in 30-hour lung preservation. METHODS: Twenty five pairs of adult mongrel dogs were divided into four groups. Donor lungs were flushed with modified ET-Kyoto solution (n = 9), with ET-Kyoto solution (n = 6), with University of Wisconsin solution group (n = 6), or with ET-Kyoto solution plus the solvents of nitroglycerin (ethanol and propylene glycol) (n = 4), then stored at 4 degrees C for 30 hours. All animals were treated with prostaglandin E1. Left lungs were transplanted and reperfused for 6 hours. RESULTS: With respect to arterial oxygen tension, peak inspiratory pressure, and wet-to-dry lung weight ratio, modified ET-Kyoto solution was significantly superior to ET-Kyoto solution. The modified ET-Kyoto solution was significantly superior to University of Wisconsin solution with respect to survival rate, arterial oxygen tension, and wet-to-dry lung weight ratio. Ultrastructural findings supported these results. CONCLUSIONS: These results suggest that modified ET-Kyoto solution is superior to University of Wisconsin solution for 30-hour lung preservation.

Acetylcysteine↗

PubMed1996

Insulin regulated PKC isoform mRNA in rat adipocytes.

Insulin and 12-O-tetradecanoyl phorbol-13-acetate (TPA) induce both glucose uptake and translocation of protein kinase C (PKC) from cytosol to membrane in insulin-sensitive tissues as previously reported by several investigators. We examined insulin-mediated PKC beta I, beta II, and epsilon translocation from cytosol to cytoskeleton, and expression of PKC alpha, beta I, beta II, gamma, and epsilon isoforms using the reverse transcription polymerase chain reaction (RT-PCR) method during treatment with insulin for 240 min in rat adipocytes. Insulin-induced increases in PKC beta I, beta II, and epsilon were greater in the cytoskeleton fraction than those in the membrane fraction. Insulin induced time-dependent increases in PKC alpha, gamma, epsilon and zeta mRNA levels for up to 240 min (555%, 117%, 236% and 138% increase, respectively). TPA also induced time-dependent increases in PKC alpha and gamma (34% and 500% increase, respectively) but not in PKC zeta. However, PKC beta I mRNA was decreased for up to 60 min and then maintained at under the basal level during stimulation with insulin and TPA. On the other hand, PKC beta II mRNA was markedly increased for up to 240 min. These results suggest that insulin-regulated PKC alpha, gamma and epsilon mRNA levels and PKC beta mRNA alternative splicing may occur in rat adipocytes.

Adipocytes↗

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

Inhibition by CsA and FK506 of the in vitro proliferative response of gamma delta T cells on stimulation with anti-TCR delta monoclonal antibody.

Tg.Tla'-3-1 mice are transgenic C3H/He mice with a Tlaa-3 gene derived from A mice. We demonstrated that spleen cells from Tg.Tlaa-3-1 mice, but not C3H/He mice, showed a proliferative response on stimulation with immobilized anti-TCR delta monoclonal antibody (mAb 3A10). Thus, Tg.Tlaa-3-1 mice can be useful for analysis of the function of gamma delta T cells. Using spleen cells from Tg.Tlaa-3-1 mice, we showed that cyclosporin A (CsA) and FK506 inhibited the in vitro proliferative response of gamma delta T cells on stimulation with anti-TCR delta mAb. The dose-dependent inhibitory effect of CsA and FK506 on proliferation of gamma delta T cells on stimulation with anti-TCR delta mAb was similar to that on proliferation of alpha beta T cells on stimulation with anti-TCF beta mAb. Inhibition by CsA and FK506 of proliferation of gamma delta T cells was not reversed by addition of rIL 2 (recombinant interleukin 2) during culture. The proliferative response of gamma delta T cells among spleen cells from TCR alpha beta-depleted Tg.Tlaa-3-1 mice was also inhibited by CsA and FK506, suggesting that the inhibition directly affected gamma delta T cells without mediation by alpha beta T cells.

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

Second transplantation with CD34+ bone marrow cells selected from a two-loci HLA-mismatched sibling for a patient with chronic myeloid leukaemia.

A 43-year-old man with chronic myeloid leukaemia underwent a second transplant with CD34+ bone marrow cells selected from his two-loci HLA-mismatched sibling after rejection of the first graft from an HLA-matched unrelated donor. By immunomagnetic positive selection, CD34+ marrow cells at 0.95 x 10(6)/kg with 97% purity and CD3+ T lymphocytes at 1.3 x 10(4)/kg were collected and transplanted. Engraftment was confirmed to be of CD34+ cell-donor origin. The patient developed only grade I acute graft-versus-host disease (GVHD) and no chronic GVHD to date. These observations suggest that allogeneic CD34+ bone marrow cells are capable of reconstituting haemopoiesis and that CD34+ selection could be applicable to T-cell depletion.

Adult↗

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

Application of clonal analysis. Differential diagnosis for synchronous primary ovarian and endometrial cancers and metastatic cancer.

Simultaneous involvement of the endometrium and the ovary by carcinoma is a familiar problem in the routine practice of surgical pathology. Such cases may be considered either examples of a single primary carcinoma with metastasis or as synchronous primary neoplasms. The distinction between these two possibilities is made based on clinicopathologic observations, and therefore may not be definitive. In the present study, the authors used molecular techniques to analyze the clonal composition of five cases of concurrent adenocarcinomas of the endometrium and ovary that were clinicopathologically diagnosed as synchronous primary tumors. Patterns of X-chromosome inactivation, mutations in the K-ras gene, mutations or allelic loss of the p53 gene, or human papillomavirus detection were identical in both endometrial and ovarian lesions in three of the cases suggesting that those three cases represented single primary tumors with metastases. In both of the other two cases, the patterns of X-chromosome inactivation clearly demonstrated the presence of independent primary tumors. The application of molecular technology may play an important role for the differential diagnosis between synchronous primary carcinomas and a single carcinoma with metastasis.

Adult↗