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Biomedical subjects

K Okabayashi

Publications and source records attributed to K Okabayashi.

At least 37 records · Page 2Linked to original sources

Video-assisted thoracoscopic esophagectomy for esophageal cancer.

BACKGROUND: The Ivor-Lewis procedure is a radical, invasive, and effective procedure for the resection of most esophageal cancers. To minimize invasiveness, we performed thoracoscopic and video-assisted esophagectomy and mediastinal dissection for esophageal cancer. METHODS: From November 1995 to June 1997, 23 patients with intrathoracic esophageal cancer, excluding T4 cancers, underwent thoracoscopic and video-assisted esophagectomy. Bilateral cervical dissections were performed as well as preparation of the gastric tube and transhiatal dissection of the lower esophagus. The cervical esophagus was cut using a stapler knife, and esophageal reconstruction was performed through the retrosternal route or anterior chest wall. Next, thoracoscopic mediastinal dissection and esophagectomy were performed. RESULTS: The mean volume of blood loss was 163 +/- 122 ml; mean thoracoscopic surgery duration, 111 +/- 24 min; mean postoperative day for patients to start eating, 8 +/- 3 days; and mean hospital stay, 26 +/- 8 days. No patient developed systemic inflammatory response syndrome postoperatively. Tracheal injury occurred and was repaired during the thoracoscopic approach in one patient. No patients died within 30 days after surgery. Postoperative complications included transient recurrent nerve palsy in five patients, pulmonary secretion retention requiring tracheotomy in two, and chylothorax in one. Five patients died of cancer recurrence within 1 year of surgery. CONCLUSIONS: Our surgical experience with thoracoscopic and video-assisted esophagectomy indicate that it is a feasible and useful procedure.

Blood Loss, Surgical↗

Molecular confirmation of a Trichophyton violaceum isolate from human black-dot ringworm.

A clinical isolate from a black-dot ringworm lesion of a 28-year-old female Japanese was investigated by morphological and biochemical analyses as well as molecular analyses. The isolate grew well on thiamine enriched agar and did not produce violet pigment, macro-conidia or micro-conidia on Sabouraud's dextrose agar. Approximately 620-bp genomic DNA fragments of the CHS1 gene were amplified from Trichophyton mentagrophytes, T. rubrum, T. tonsurans and T. violaceum by polymerase chain reaction (PCR) and sequenced. The chitin synthase 1 (CHS1) nucleotide sequences of the clinical isolate showed more than 97% similarity to that of T. violaceum and less than 96% similarity to that of T. mentagrophytes, T. rubrum and T. tonsurans. The phylogenetic analysis of their sequences revealed that the clinical isolate was genetically close to T. violaceum and distinct from T. mentagrophytes, T. rubrum and T. tonsurans. Therefore, the isolate was confirmed as T. violaceum by mycological examination and molecular analyses.

Adult↗

[Pronounced progression of interstitial pneumonia in a precious metal worker].

A 43-year-old man who had been engaged in the precious-metal processing industry for 18 years was admitted to our hospital because of shortness of breath on exertion. Chest roentgenograms disclosed ground glass opacities and annular-nodular shadows in the basal area of the right lung field and almost all of the left lung field. A video-assisted thoracoscopic lung biopsy was performed, and histologic examination disclosed usual interstitial pneumonia (UIP). Mineral analysis revealed high modes of silicon and aluminum, two elements consistent with the materials used in the patient's factory. The histopathological findings indicated interstitial pneumonia caused by the inhalation of dust particles. After corticosteroid therapy, computed tomographic scans disclosed that the ground glass opacities had subsided, but that honeycomb shadows remained. A chest roentgenogram taken 2 years earlier demonstrated only minute granular lesions in the basal area of right lung field. The interstitial shadows had progressed significantly over the intervening 2-year span. The findings in this case should be of value to the etiologic study of UIP.

Adult↗

[Home medical care from our hospital].

From April, 1996 to March, 1999, our hospital provided home medical care on a 24-hour basis for fifty patients with advanced or terminal cancer. Eventually, twenty-four patients died at home and twenty-six in the hospital. Stability of health status, the presence of willing and able caregivers, as well as a greater number of house-calls are suggested factors in facilitating a death at home. However, the patients who died in the hospital were obliged to readmit themselves until the time of death due to caregivers' reasons such as fatigue, emotional stress and/or health problems. In addition to timely availability and accessibility of respite care, psychosocial support for family caregivers by liaison nurses remains an issue to be solved in future.

Caregivers↗

The number of lymph node metastases influences survival in esophageal cancer.

BACKGROUND AND OBJECTIVES: Lymph node involvement adversely affects the survival of patients with esophageal cancer. We retrospectively investigated whether the number of involved lymph nodes and the degree of lymph node dissection affect survival. PATIENTS AND METHODS: Eighty-eight patients underwent surgical resection and reconstruction for T -T3 thoracic esophageal squamous cell carcinoma. Patients were classified into three groups: group 1, 32 patients without lymph node involvement; group 2, 26 patients with 1 to 3 positive nodes; and group 3, 30 patients with > or = 4 involved lymph nodes. RESULTS: The 3-year and 5-year survival rates were 34.8% and 30.0% in group 1, 30.0% and 22.7% in group 2, and 14.8% and 0% in group 3, respectively. The mean survival time (MST) X +/- SD of the patients in group 3 (453.06+/-74.5 days) was significantly shorter than in group 1 (450.1+/-450.5, P = 0.0005) and group 2 (937.3+/-1317.9, P = 0.0295). For patients in groups 1 and 2, the MST for three-field lymph node dissection (1136.9+/-1476.4 days) was longer than for two-field lymph node dissection (1007.4+/-1476.4 days, P = 0.0355). However, in group 3, there was no survival advantage to three-field lymph node dissection. CONCLUSION: We conclude that the survival in patients with thoracic esophageal cancer involving four or more nodes, is poorer than in patients with lesser involvement. Three-field lymph node dissection does contribute to prolonged survival in patients with node-negative disease or fewer than four positive nodes.

Adult↗

Y-shaped tracheobronchial stent for carinal and distal tracheal stenosis.

A Y-shaped tracheo-bronchial tube was designed and used for two patients with carinal stenosis following a lower tracheal resection in one case and a malignant tracheal fistula in the other. The tube consisted of three parts including a Y-shaped, thin-walled, soft silicone stent; a spiral-wire-reinforced main tube; and a curved tracheostomy tube. The stent was inserted easily and comfortably through the tracheostomy under fiberoptic bronchoscopic guidance with minimal local anesthesia. The positioning stability of the tube was excellent because of the carina-shaped structure of the tube end. Resistance to compression was satisfactory due to the embedded spiral wire. The insertion procedure through the tracheostomy was smooth, even in patients whose respiratory condition was severe or critical. Satisfactory phonational activity was also provided by breathing through the hole on the tube back up to the vocal cord. Bronchoscopic inspection was uncomplicated, and the patients themselves could easily clean the stent. Since palliation of the airway obstruction is the main purpose of such a stent for patients with either severe lower tracheal or carinal stenosis, and because of the difficulty of ordinary stent insertion in this part of the airway, this device appears to offer excellent stability and easy insertion of the stent. In addition, the ease of maintenance and suctioning through the tracheostomal end allows for an excellent quality of life in which the patients are able to return to their homes.

Adult↗

Stenting for airway obstruction in the carinal region.

BACKGROUND: Recent progress on airway stents has provided sufficient airway patency for patients with airway obstruction; however, when the stenosis exists in the carinal zone, establishing an excellent airway condition is still troublesome because of the anatomic structure. METHODS: We treated 15 patients with severe tracheobronchial stenosis involving a carinal bifurcation region, using several types of stenting devices (long T-tube, T-Y tube, wire reinforced Y tracheostomal tube, Freitag Dynamic stent [Karl Storz, Tuttlingen, Germany], and covered metallic stent). All patients had advanced inoperable tumors (lung cancer, n = 6; esophageal cancer, n = 3; thyroid cancer, n = 3; mediastinal tumor, n = 3). RESULTS: All but 2 patients had immediate relief of respiratory symptoms. One patient died of respiratory failure caused by pulmonary lymphatic spread 3 days after Dynamic stent insertion. In 1 patient with severe left main bronchial stenosis due to lung cancer, effective palliation was not achieved by insertion of a covered metallic stent because of its insufficient expansion against the stenosis. Mean survival after successful stenting was 4.3 months (range, 1 to 15 months). There were no complications directly attributable to the stents. CONCLUSIONS: As evidenced by the clinical effectiveness, airway stenting for inoperable tumor is valuable in such patients. Choosing a stent that will fully cover the lesion and allow sufficient tolerance against compression is important to successful stenting. Benefits such as ease of phonation and stent maintenance should also be considered.

Bronchial Diseases↗

Tracheal transplantation for carinal reconstruction in dogs.

BACKGROUND: Experimental carinal allotransplantation has been performed with tracheocarinal Y-shaped allografts in dogs. In this study we tried canine carinal reconstruction with cylindrical allografts. MATERIAL AND METHODS: Carinal reconstruction was performed with allotransplantation of cylindrical trachea in dogs, and graft healing was evaluated by bronchoscopic observation, mucosal blood flow measurement, and histologic examination. A section of the recipient carina containing five tracheal rings and two main stem bronchi was removed, and a donor trachea seven rings long was inserted between the recipient trachea and the left main stem bronchus; then side-to-end anastomosis was performed between the graft midportion and recipient right main stem bronchus (new carina). The grafts were wrapped with pedicled omentum. Fresh grafts were transplanted into one group of dogs (n=8 ), and grafts cryopreserved for 1 week were transplanted into another group (n=7). RESULTS: No anastomotic leakage occurred in any dog. Excellent healing of grafts and graft anastomoses was observed by fiberoptic bronchoscopy in six dogs (75%) in the fresh graft group and in four dogs (57%) in the cryopreserved graft group. The mucosal blood flow in the new carina decreased remarkably and, although it recovered, mucosal blood flow remained under the preoperative level on day 28 after the operation. CONCLUSION: Cylindrical tracheal allotransplantation is useful for carinal reconstruction, and the method of side-to-end anastomosis between the donor trachea and recipient bronchus is a feasible and accessible procedure in dogs.

Anastomosis, Surgical↗

[Therapeutic strategy for pleural mesothelioma].

Generally pleural mesothelioma is divided into two histologic types: localized and diffuse. Most cases of the former are considered to be benign and the latter malignant. The treatment strategy for these tumors has been investigated, including various surgical and chemotherapeutic approaches. In spite of these efforts. no curative method for malignant mesothelioma has been established yet, although the gene therapy is expected to be the most powerful tool in the near future.

Adult↗

Extended operation for T4 lung carcinoma.

The extended surgery for T4 lung carcinoma was reviewed. From literature in the last decade, the 5-year survival rate has been under 10% worldwide. However a more favorable prognosis will be expected nowadays because of the progress of perioperative intensive care and appearance of effective anticancerous agents for induction chemotherapy. We compared the results of surgery for T4 lung carcinoma from 1978 to 1989, to those from 1992 to 1997. The 3 and 5-year survivals in the former period were 6.8% respectively, however in the latter period the 3-year survival rate rose to 24.6%. In patients with T4, the prognoses are different according to the involved organs by lung carcinoma. Generally, combined resection of the trachea, carina, descending aorta and left atrium show better prognoses compared to that of the esophagus and liver. We consider that malignant pleural effusion with N2 should not be the object for panpleuropneumonectomy. In our series from 1992 to 1997 median survival time (MST) of T4 with N0 or N1 was 25.5 months, on the other hand MST with N2 or N3 was 14.2 months. Histologically patients with squamous cell carcinoma showed a better prognosis than those with adenocarcinoma. From these results, in the extended operation for T4 we may expect more favorable prognoses in cases with involvements of the trachea, carina, aorta and left atrium, and with N0 or N1, histologically squamous cell carcinoma.

Adenocarcinoma↗

Inhaled nitric oxide does not increase rat pulmonary allograft rejection.

BACKGROUND: There is evidence that inducible nitric oxide (NO) may be directly related to the process of allograft rejection. Because of its strong pulmonary vasodilatory activity, inhaled NO (INO) has recently been used as a therapeutic option for allograft dysfunction after lung transplantation. The action of inducible NO and inhaled NO seems contradictory for preserving posttransplantation pulmonary allograft function. INO used for lung transplant recipients may actually enhance acute allograft rejection. We studied the effect of INO on acute allograft rejection with a rat pulmonary allograft model. METHOD: A total of 24 left lung allotransplantations were performed from Lewis donors into F344 recipients. Animals were divided into two groups and inhaled either room air alone or 20 ppm NO with room air in a closed chamber immediately after transplantation until rats were killed on days 7 and 14. During observation, NO uptake was monitored by measuring serum NO2-/NO3- level. Acute rejection was evaluated by use of a semiquantitative radiographic scoring method (aeration score: 0 to 6, opaque to normal appearance) and rejection score (0 to 4, no sign of rejection to diffuse mononuclear infiltration). RESULTS: Markedly elevated serum NO2-/NO3- levels were observed in the NO inhalation group compared with levels in the normal air inhalation control group (110.8 +/- 25.3 vs 16.3 +/- 4.0 micromol/L/ml on day 7, p < 0.01; 107.0 +/- 30.9 vs 16.8 +/- 4.8 micromol/L/ml on day 14, p < 0.01). However, no positive effect of INO on acute rejection was found histologically or radiographically. CONCLUSION: The effect of INO on acute rejection is likely so minimal as not to be clinically relevant.

Administration, Inhalation↗

Carinal resection and reconstruction for recurrent lung cancer.

A patient with a recurrent tumor in the trachea adjacent to the right main bronchus was treated by surgical resection 19 months after undergoing surgery for the primary cancer. The patient had previously undergone right upper lobectomy for T1N0M0 stage I squamous cell carcinoma. A carinal resection was performed which included 4 rings of the trachea, 2 rings of the right main bronchus, and 1 ring of the left main bronchus. Reconstruction consisted of an end-to-end anastomosis of the trachea and left main bronchus, and an end-to-side anastomosis of the right and left main bronchi. The postoperative course was uneventful, and at present the patient is healthy 12 months following reoperation.

Aged↗

Free radical-mediated tissue injury in acute lung allograft rejection and the effect of superoxide dismutase.

BACKGROUND: The role of monocytes and neutrophils is crucial during acute allograft rejection. They have the capacity to generate toxic reactive oxygen intermediates in response to specific agonists that may act as tissue destructive molecules. We examined the possibility of reactive intermediate-mediated tissue injury in acute lung allograft rejection, as well as the effect of superoxide dismutase. METHODS: Allogenic (Brown Norway to F344) or syngenic (F344 to F344) rat left-lung transplantation was performed. Generation of reactive oxygen intermediates in peripheral blood was evaluated by the method of luminol-dependent chemiluminescence. Cell membrane phospholipid peroxidation in the graft was measured as malondialdehyde concentration. The third group of animals having allografts received bovine erythrocyte superoxide dismutase (5,000 U/kg intravenously every 12 hours after transplantation). RESULTS: Relative chemiluminescence response in the allograft recipient to normal F344 was elevated on postoperative day 1 (257%), then decreased slightly on day 3 (156%) and was elevated again on day 7 (560%) as the process of rejection progressed. Allograft tissue malondialdehyde levels (248.37 +/- 112.35 nM/whole lung, n = 6; p < 0.05 by Student's t test) were higher than isograft levels (139.29 +/- 35.93 nM/whole lung, n = 6) on day 7. Superoxide dismutase treatment significantly ameliorated the histologic degree of rejection on day 7. CONCLUSIONS: These results demonstrate the tissue destructive activity of reactive oxygen intermediates during lung allograft rejection. To scavenge free radicals may be a useful therapeutic modality in the management of acute lung allograft rejection.

Acute Disease↗

Is video-assisted thoracoscopic surgery suitable for resection of primary lung cancer?

We investigated the validity of thoracoscopic surgery-in patients with primary lung cancer undergoing lobectomy. 14 primary lung cancer patients treated by typical VATS lobectomy and one by anatomical segmentectomy, were compared with 56 patients with Stage-I lung cancer undergoing standard lobectomy (control group), the results focusing on the lymph-nodes dissected. All 14 lobectomy patients showed primary lesions of size less than 3 cm. Following classification of the lymph-nodes into groups I (hilar lymph node) and II (mediastinal lymph node), we compared results according to the sites of the lobectomies conducted. Numbers of dissected lymph-nodes were similar in patients whether undergoing standard thoracotomy or VATS lobectomy. We also investigated what histological types of cancer should be treated by VATS lobectomy by comparing preoperative and operative staging in the control group. The results showed that in most patients with squamous-cell carcinoma judged as T1 N0 M0 the staging corresponded, the other patients actually being in N1 (Stage II). Of Patients with adenocarcinoma of T1 N0 M0, however, 14% had lymph-node metastasis even into the superior mediastinum, i.e., Stage III. The overall findings suggest at present that VATS lobectomy should be applied preferably to patients with a histological typing such as squamous cell carcinoma or alveolar cell carcinoma of relatively early stage, i.e. preoperative Stage I.

Adenocarcinoma↗

Inhibition of inducible nitric oxide synthase prolongs rat lung allograft survival.

Nitric oxide (NO) has been demonstrated to be an important immunoregulation molecule in the process of cellular immunologic interactions. Our recent results demonstrated that NO is produced in association with acute allograft rejection and NO inhibition may suppress rejection histologically. This data provides direct evidence of NO in allograft rejection and the immunosuppressive potential of NO inhibitors. In this paper, the effect of NO inhibition on allograft survival was evaluated to investigate the capacity of NO inhibitors as immunosuppressive agents. Seventeen rat left lung transplants from BN donors to F344 recipients were accepted for this study. After surgery, recipients were randomized into two groups and received either aminoguanidine (AG), a highly selective NO synthase inhibitor, 200 mg/kg, intra-peritoneal every 6h (n = 13) or normal saline treatment (n = 4). No production was determined from the recipient's serum nitrite and nitrate levels. Graft survival was monitored via semi-quantitative radiographic aeration scores (AS: 0 = opaque lung to 6 = normal appearing lung). The nitrite and nitrate levels were clearly detectable before the radiographic finding associated with rejection became obvious. Production of NO was significantly inhibited by AG treatment. AG treatment prolonged allograft survival radiographically (12.0 days and 6.0 days for treated and untreated groups respectively, p = 0.0001). These data suggest that the inducible NO is produced in association with acute lung allograft rejection and may serve as a sensitive rejection marker. NO inhibition significantly prolonged rat lung allograft survival but failed to induce immunological tolerance.

Animals↗

Primary tracheal fibrosarcoma in a child: a case of tracheal resection under ECMO support.

We report a case of severe airway obstruction due to endotracheal fibrosarcoma in a 3-year-old boy. Successful tracheal resection and reconstruction was performed under extracorporeal membrane oxygenation support. A solid, elastic hard tumor with a smooth surface was attached by a tiny stalk structure to the membranous part of the lower trachea. Histological findings of the tumor were consistent with infantile fibrosarcoma, showing proliferation of spindle cells forming interlacing patterns.

Airway Obstruction↗