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Wataru Kitagawa

Publications and source records attributed to Wataru Kitagawa.

26 records · Page 2Linked to original sources
PubMed2002

Trial of autotransplantation of cryopreserved thyroid tissue for postoperative hypothyroidism in patients with Graves' disease.

BACKGROUND: Some patients with Graves' disease who select surgical therapy so they can discontinue antithyroid medication require lifelong levo-thyroxin (l-T4) replacement therapy because of irreversible postoperative hypothyroidism. The aim of this study was to enable the replacement of absent thyroid hormone through autotransplanted thyroid tissue that had been cryopreserved since the initial thyroid operation, and to release these patients from lifelong l-T4 administration. STUDY DESIGN: At the time of subtotal thyroidectomy for Graves' disease, the surgical specimen was partially cryopreserved at -196 degrees C until it was used for autotransplantation. After obtaining sufficient informed consent, four patients with postoperative hypothyroidism underwent autotransplantation of cryopreserved thyroid tissues. These patients required 50 to 150 microg/day of l-T4 at 1.8, 3.4, 3.5, and 2.8 years after operation. For the transplantation, 2.5 to 3.5 g of cryopreserved thyroid tissue was autotransplanted into the forearm muscle of each patient. RESULTS: In three of the patients, l-T4 administration could be discontinued and the clinical symptoms of hypothyroidism disappeared because of an improved serum thyroid-stimulating hormone level. Pathologic and immunohistochemical examinations of the thawed cryopreserved tissue demonstrated well-preserved thyroid structure and thyroglobulin-positive follicular cells and colloids, suggesting that the transplanted material was functional. In addition, 123I scintiscanning in patients 1 and 2 indicated an accumulation of radioactive iodine at the transplantation sites. One patient, who was able to discontinue l-T4 administration for 6 months, subsequently required l-T4 again because of recurrent hypothyroidism. BACKGROUND: Despite a few remaining uncertainties that must be resolved before this procedure is optimized, autotransplantation of cryopreserved thyroid tissue promises to be a useful therapeutic procedure for treating permanent postoperative hypothyroidism in patients with Graves' disease.

Adult↗
PubMed2002

Novel 2,4-dichlorophenoxyacetic acid degradation genes from oligotrophic Bradyrhizobium sp. strain HW13 isolated from a pristine environment.

The tfd genes of Ralstonia eutropha JMP134 are the only well-characterized set of genes responsible for 2,4-dichlorophenoxyacetic acid (2,4-D) degradation among 2,4-D-degrading bacteria. A new family of 2,4-D degradation genes, cadRABKC, was cloned and characterized from Bradyrhizobium sp. strain HW13, a strain that was isolated from a buried Hawaiian soil that has never experienced anthropogenic chemicals. The cadR gene was inferred to encode an AraC/XylS type of transcriptional regulator from its deduced amino acid sequence. The cadABC genes were predicted to encode 2,4-D oxygenase subunits from their deduced amino acid sequences that showed 46, 44, and 37% identities with the TftA and TftB subunits of 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) oxygenase of Burkholderia cepacia AC1100 and with a putative ferredoxin, ThcC, of Rhodococcus erythropolis NI86/21, respectively. They are thoroughly different from the 2,4-D dioxygenase gene, tfdA, of R. eutropha JMP134. The cadK gene was presumed to encode a 2,4-D transport protein from its deduced amino acid sequence that showed 60% identity with the 2,4-D transporter, TfdK, of strain JMP134. Sinorhizobium meliloti Rm1021 cells containing cadRABKC transformed several phenoxyacetic acids, including 2,4-D and 2,4,5-T, to corresponding phenol derivatives. Frameshift mutations indicated that each of the cadRABC genes was essential for 2,4-D conversion in strain Rm1021 but that cadK was not. Five 2,4-D degraders, including Bradyrhizobium and Sphingomonas strains, were found to have cadA gene homologs, suggesting that these 2,4-D degraders share 2,4-D degradation genes similar to those of strain HW13 cadABC.

2,4-Dichlorophenoxyacetic Acid↗
PubMed2002

Immunohistochemical, biochemical and immunoelectron microscopic analysis of antigenic proteins on neuroendocrine cell tumors using monoclonal antibody HISL-19.

The monoclonal antibody HISL-19 was originally generated after immunizing BALB/c mice with human islet cells. We used this antibody to study a wide variety of neuroendocrine (NE) and non-NE tumors by immunohistochemical, immunoelectron microscopic, and biochemical (Western blotting) techniques. Of the thyroid tumors, HISL-19 specifically immunoreacted with medullary carcinoma of the thyroid (MCT); of the pancreatic tumors, it reacted with islet cell tumors such as insulinomas and a gastrinoma; of the adrenal tumors, it reacted with pheochromocytoma. HISL-19 showed particularly strong immunoreactivity to a gross granular material at the perinuclear area in the MCT and malignant pheochromocytoma but not in the benign pheochromocytoma, although the latter cells showed a faint and homogenous positive reactivity in the cytoplasm. The strongly HISL-19-positive material was found to consist of newly synthesized antigenic proteins with a molecular weight between 60 and 65 kilodaltons (kDa) by Western blotting. Immunoelectron microscopic analysis revealed that this antigenic protein was located in the secretory granules that appear markedly in malignant endocrine tumors, usually located close to the nucleus. Thus, HISL-19 is a useful and specific marker for the immunohistochemical diagnosis of NE cell tumors. The specific antigenic proteins of HISL-19 were defined in MCT and malignant pheochromocytoma. These proteins are speculated to be actively synthesized and more highly produced in the secretory granules of malignant endocrine tumors than benign ones. Thus, a preoperative immunohistochemical study using HISL-19 might be useful for predicting the grade of malignancy of endocrine malignant tumors and thus help determine an appropriate operative procedure, in addition to being a useful marker of neuroendocrine cell tumors.

Adenoma, Islet Cell↗
PubMed2002

Radioguided parathyroidectomy for reexploration of primary hyperparathyroidism-- a case report.

BACKGROUND: We report a case of radioguided parathyroidectomy using a hand-held gamma probe for the reexploration of primary hyperparathyroidism. CASE REPORT: The patient was a 66-year-old Japanese woman. She had previously undergone surgical exploration for primary hyperparathyroidism due to a left inferior parathyroid tumor detected by 99mTc-methoxyisobutylisonitrile (MIBI) scintigraphy. However, the pathological diagnosis of the resected tumor was adenomatous goiter. 99mTc-MIBI scintigraphy was performed again and revealed an abnormal uptake close to the right lower lobe of the thyroid. However, venous sampling for PTH measurements did not support this finding. Sestamibi was injected and the radioactivity was measured pre- and intraoperatively with a hand-held gamma probe. With the patient under general anesthesia, the tumor, which was adjacent to the right recurrent laryngeal nerve, was resected, but it contained only a low level of radioactivity ex vivo, indicating that it was not a parathyroid tumor. A hand-held gamma probe accurately located the radioactive parathyroid tumor in the right lower neck. The resected tumor measured 15 x 6 mm and weighed 331 mg. The pathological diagnosis was parathyroid adenoma. CONCLUSIONS: Radioguided parathyroidectomy is useful to localize parathyroid tumors not only in primary hyperparathyroidism at the initial neck exploration but also for reexploration.

Adenoma↗
PubMed2002

[Indications for and limitations of endoscopic thyroid surgery].

Endoscopic thyroid surgery has become a common procedure in recent years, mainly because of its cosmetic advantages. Generally two methods are used to obtain a working space: CO2 insufflation and anterior neck skin lifting. The incision sites for approaching the thyroid are the chest wall, mammary areolar area, axillary and submandibular area, in addition to the neck. Among the new operative devices, the ultrasonically activated scalpel has contributed to the development of endoscopic thyroid surgery. Based on our experience of more than 180 cases using our original endoscopic method, video-assisted neck surgery(the VANS method), we here report the clinical outcome and usefulness of the method. The operating time and blood loss in patients with 161 benign thyroid tumors were statistically compared between the small-tumor group (n = 138, < 5 cm) and the large-tumor group (n = 23, > or = 5 cm). More than 60% of the benign and 7.1% of the malignant thyroid tumors were operated on using the VANS method. Near or subtotal lobectomy was the most common procedure (64.4%) for benign tumors. Malignancy was defined as a papillary carcinoma < 1 cm in diameter. Total lobectomy with lymph node clearance was performed for all malignant cases. Although the operating time and blood loss were statistically greater in the large-tumor group than the small-tumor group, with increased experience it was possible to remove tumors of up to 7.4 cm safely. Our findings show that the VANS method is feasible, practical, and safe, and has great cosmetic benefits. However, it must be remembered that the intrinsic surgical goal of treatment should not be compromised in the pursuit of less-invasive surgery. Care must be taken to select appropriate patients carefully and to train surgeons sufficiently in the techniques required.

Adolescent↗
PubMed2002

Evaluation of an alternative, subclavicular approach to thyroidectomy.

BACKGROUND: After presenting with the common finding of a nodular goiter, many patients refuse surgery because of the potential for a conspicuous anterior neck scar. Despite the development of endoscopic approaches to neck dissections, it can be difficult to remove a large thyroid tumor using such approaches. MATERIAL/METHODS: We attempted thyroid lobectomies via a subclavicular approach in three cases - three women whose ages ranged from 36-45 years old. Each patient was diagnosed with a cytologically-benign nodular goiter with a diameter greater than 60 mm. Subclavicular incisions were made with the length being determined by the size of the tumor and with the thyroid being approached laterally for resection. RESULTS: Despite a maximum tumor diameter of greater than 70 mm, our operative technique was comparable to conventional methods with respect to surgical exposure, safety and operation time. Cosmetically, each patient was satisfied with the post-operative results. CONCLUSIONS: We believe that the subclavicular approach to thyroidectomy is a safe and cosmetically-superior alternative to conventional surgery, even in cases that are too large to approach endoscopically.

Adult↗
PubMedDate not supplied

Histological study of papillary thyroid carcinoma treated with percutaneous ethanol injection therapy.

An 86-year-old male patient was treated by percutaneous ethanol injection therapy (PEIT), following tumorectomy of a papillary thyroid carcinoma and a modified radical neck dissection for its metastasis. After seven treatments with PEIT, the patient was admitted to hospital for a tracheotomy to treat progressive severe dyspnea. Seven days later the patient died from acute renal failure caused by diabetic ketoacidosis. At autopsy, tumor masses were found to comprise mostly scar tissue, and the remaining neoplastic cells often showed anaplastic changes. Fresh coagulation necrosis and hemorrhages were scattered throughout the tumor lesions and their microvessels were occasionally occluded by thrombus. These changes were seen prominently, especially at the central areas of PEIT treatment. Given these findings, we believe that PEIT may be useful in providing local control for the progression of thyroid cancer, especially in cases of unresectable malignant thyroid tumors.

Administration, Cutaneous↗