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T Obara

Publications and source records attributed to T Obara.

At least 145 records · Page 8Linked to original sources
PubMed1993

Mucin-producing tumor of the pancreas: natural history and serial pancreatogram changes.

The clinical features and changes of the pancreatic duct system in nine patients with mucin-producing tumor of the pancreas were serially studied to clarify the natural history and evolution of pancreatograms. The observation periods ranged from 6 to 50 months (mean, 30 months), and all patients were examined by endoscopic retrograde pancreatography two or more times. Four of the nine cases exhibited obvious progression of pancreatic duct dilation in association with increased amounts of mucin in the dilated duct, whereas five did not show apparent progression of ductal changes. Changes in the pancreatograms of mucin-producing tumor occurred when mucin secretion by the tumor became prominent, and such cases frequently presented with abdominal pain and pancreatitis. In contrast, most of the branch duct type remained unchanged; all three cases of main duct type showed progression of pancreatograms. There was no apparent relationship between degree and progression of ductal changes and the tumor malignancy.

Aged↗
PubMed1993

[Lymphoscintigraphy with 99mTc-DTPA-HSA in the diagnosis of protein-losing gastroenteropathy].

We evaluated the diagnostic capability of technetium-99m-diethylene triamine pentaacetic acid-human serum albumin (99mTc-DTPA-HSA) lymphoscintigrapy in a patient with protein-losing gastroenteropathy. 99mTc-DTPA-HSA (total 740 MBq) was injected subcutaneously into the digital webs of the both feet. With a gamma camera, whole-body and abdominal lymphoscintigrams were obtained after the injection of the radioisotope: early images and delayed images taken 5-15 min and 50-60 min, respectively, after the injection. A few days later, the dynamic lymphoscintigraphy was also performed. Lymph fluid leakage into the small bowel and the sites of the leakage were detected. It was concluded that lymphoscintigraphy with 99mTc-DTPA-HSA was a useful diagnostic tool in patients with protein-losing gastroenteropathy.

Adult↗
PubMed1992

[Diagnosis and treatment of primary hyperparathyroidism].

Primary hyperparathyroidism is nowadays not uncommon in Japan. The incidence is considered to be one in every 2,500 to 5,000 persons. Many advances have occurred in diagnosis, localization study, and treatment of the disease. Surgery remains the treatment of choice for patients with primary hyperparathyroidism. Notwithstanding, there are still controversies concerning the management of primary hyperparathyroidism. One of the current disputable points is whether the use of localization study in patients who are undergoing and initial operation is justified or not. Another is whether unilateral exploration is justified or not. The basic reasons for these persistent controversies is the lack of consensus about incidence of multiglandular hyperplasia or double adenomas. Our observation implies that the incidence of hyperplasia or double adenomas among all the patients with primary hyperparathyroidism in Japan is lower than that in western countries. Since diagnostic accuracy of noninvasive localization studies has recently improved, it seems reasonable to adopt unilateral neck exploration in our country. It is also characteristic in Japan that the incidence of parathyroid carcinoma is relatively high (6%) compared with that reported in many other countries.

Adenoma↗
PubMed1992

New neplanocin analogues. 1. Synthesis of 6'-modified neplanocin A derivatives as broad-spectrum antiviral agents.

Novel neplanocin A analogues modified at the 6'-position, i.e., 6'-deoxy analogues (2, 3, 6, 9, 20), 6'-O-methylneplanocin A (15), and 6'-C-methylneplanocin A's (22a and 22b) have been synthesized and evaluated for their antiviral activity in a wide variety of DNA and RNA virus systems. These compounds showed an activity spectrum that conforms to that of S-adenosylhomocysteine hydrolase inhibitors. They were particularly active against pox- (vaccinia), paramyxo-(parainfluenza, measles, respiratory syncytial), arena- (Junin, Tacaribe), rhabdo- (vesicular stomatitis), reo-, and cytomegalovirus. In order of (increasing) antiviral activity, the compounds ranked as follows: 3 less than 15 approximately 20 less than 6 less than 9 approximately 2 less than 22a. Of the two diastereomeric forms of 22, only 22a was active; 22a surpassed neplanocin A both in antiviral potency and selectivity. Compound 22a appears to be a promising candidate drug for the treatment of pox-, paramyxo-, arena-, rhabdo-, reo-, and cytomegalovirus infections.

Adenosine↗
PubMed1992

A silicone prosthesis for covering a large tracheal defect in patients who underwent surgery for locally recurrent aggressive thyroid cancer.

Following the usual sleeve or window resection of the trachea, reconstruction of the trachea can be carried out without difficulty in patients with aggressive thyroid cancer. When the cancer recurs locally in those patients, reoperation often yields a large tracheal defect, for which a commercially available tracheostomy cannula or a silicone-tube does not fit. By using a technique in the maxillofacial prosthetic field, it has become possible to make a new type of prosthesis which is more comfortable and acceptable to the patients with a large tracheal defect. A new type of silicone rubber prosthesis is made individually from the mold of each patient. Several appointments are required for adjustments by the chair side. It must tightly obstruct the tracheostomy stoma so that the patient can easily breathe, speak and take oral fluids. Patients can easily remove and replace this device by themselves and care of the prosthesis is easy. The practical use of this type of prosthesis in three patients is reported herein.

Adenocarcinoma↗
PubMed1992

Increased soluble CD4 and decreased soluble CD8 molecules in patients with Sjögren's syndrome.

PURPOSE: A new enzyme-linked immunosorbent assay for soluble CD4 (sCD4) and soluble CD8 (sCD8) molecules has been developed. We estimated the concentrations of these molecules in patients with Sjögren's syndrome and in patients with systemic lupus erythematosus (SLE) serving as a control population for non-Sjögren's inflammatory disease, since several findings suggestive of an aberration of immunocompetent cells have been reported in these autoimmune diseases. PATIENTS AND METHODS: The study population consisted of 41 patients with Sjögren's syndrome (28 cases of the primary form and 13 cases of the secondary form), 66 patients with SLE, and 43 normal individuals. Serum samples and clinical and laboratory data were collected from each patient and control. Assays of the sCD4 and sCD8 molecules were performed using an enzyme-linked immunosorbent kit developed by T Cell Science Inc., Cambridge, MA. RESULTS: The concentration of sCD4 was significantly increased in patients with both primary and secondary Sjögren's syndrome as compared with that in the control subjects. In contrast, sCD8 was significantly decreased in patients with primary disease but not in patients with secondary disease. A low or high concentration of sCD8 was significantly correlated with the presence of anti-SS-A antibody or hypocomplementemia, respectively. A similar significant correlation was noted between an increased sCD4 concentration and increased serum IgG level. In patients with SLE, the levels of both sCD4 and sCD8 were significantly increased. CONCLUSION: These observations represent the first evidence of an increased level of the sCD4 molecule and a decreased level of the sCD8 molecule and an association with immunologic abnormalities in Sjögren's syndrome. The increased and decreased levels of these soluble molecules observed may play a pathologic role in patients with Sjögren's syndrome.

Adult↗
PubMed1992

Multicentric development of pancreatic intraductal carcinoma through atypical papillary hyperplasia.

We report a case of multiple intraductal carcinomas of the pancreas associated with diffuse atypical papillary hyperplasia. A 67-year-old Japanese man with a complaint of epigastric pain was examined by endoscopic retrograde pancreatography, which demonstrated multiple dilated branches of the pancreatic duct in the body and tail of the pancreas. Histologic examination on the resected pancreas showed diffuse atypical papillary hyperplasia in multiple dilated ducts associated with multiple intraductal carcinomas. Histologic features are described and multicentric carcinogenesis through atypical papillary hyperplasia is discussed.

Aged↗
PubMed1992

Papillary adenoma of the pancreas with excessive mucin secretion.

A 68-year-old woman with papillary adenoma of the pancreas with excessive mucin secretion is reported. The patient was initially diagnosed as having chronic pancreatitis because of a history of repeated attacks of pancreatitis and localized dilatation of the main pancreatic duct. Four years later, endoscopic retrograde pancreatography showed markedly diffuse dilatation of the entire main pancreatic duct with amorphous filling defects of mucin. Excretion of mucin was observed through the enlarged orifice of Vater's ampulla. The patient was treated with distal pancreatectomy, and papillary adenoma with abundant mucin in the cytoplasm was histologically demonstrated. We describe unique clinical features of "mucin-producing pancreatic tumor" and discuss an important role of endoscopic retrograde pancreatography in the diagnosis.

Ampulla of Vater↗
PubMed1992

Antiviral activities of ribavirin, 5-ethynyl-1-beta-D-ribofuranosylimidazole-4-carboxamide, and 6'-(R)-6'-C-methylneplanocin A against several ortho- and paramyxoviruses.

5-Ethynyl-1-beta-D-ribofuranosylimidazole-4-carboxamide (EICAR) and 6'-(R)-6'-C-methylneplanocin A (TJ13025) are two novel antiviral agents which are targeted against IMP dehydrogenase and S-adenosylhomocysteine hydrolase, respectively. These compounds have been examined for their activities against various strains of orthomyxoviruses (influenza virus) and paramyxoviruses (parainfluenza virus, mumps virus, measles virus, and respiratory syncytial virus) in vitro. EICAR was 10- to 59-fold more active than ribavirin and TJ13025 was 32- to 330-fold more active than ribavirin against parainfluenza virus types (2 and 3), mumps virus, and measles virus. EICAR was also more active than ribavirin against respiratory syncytial virus and influenza virus, whereas TJ13025 was virtually inactive against these viruses. The 50% virus-inhibitory concentrations of EICAR and TJ13025 were generally within the 0.1- to 1-microgram/ml range. Although the compounds did not prove cytotoxic to stationary host cells (HeLa, Vero, MDCK, and LLCMK2) at a concentration of 200 micrograms/ml, concentrations of 4 to 13 micrograms/ml inhibited the growth of dividing cells. EICAR and TJ13025 should be further pursued as candidate drugs for the treatment of ortho- and paramyxovirus infections.

Adenosine↗
PubMed1992

Experimental study on adrenal autografts in rats to preserve normal adrenocortical function after bilateral adrenalectomy.

In order to establish a technique for successful adrenal tissue autotransplantation, we conducted an experimental study with rats, in which we investigated the effects of the total amount of grafted tissue and the size of each graft piece. Three 'amount' factor levels (1/4 of a gland and 1 and 2 glands) and two 'size' factor levels (1-mm3 fragments and a paste-like mince) were studied. The total amount of grafted adrenal tissue affected the amount of steroid secreted. Autografting of 1/4 of a gland resulted in corticosterone secretion at the normal basal level, but grafting of more than 1 gland enabled the rats to withstand stress better. The take of the grafts with the two different size levels did not differ.

Adrenal Glands↗
PubMed1992

[Usefulness of selective endoscopic retrograde pancreatography (selective ERP) and endoscopic pancreatic biopsy (EPB) in the diagnosis of mucin-producing tumor of the pancreas].

Selective ERP and EPB were employed in the diagnosis of mucin-producing tumor (MPT) of the pancreas and their usefulness was evaluated. Thirty five cases of MPTs were subdivided into three subtypes, i.e., 1) main duct type, 2) branch duct type and 3) peripheral type (mucinous cystadenoma/cystadenocarcinoma). Selective ERP was proved to be useful in demonstrating precise and whole pancreatograms, especially in revealing multiple lesions, when compared with standard ERP. Selective ERP could demonstrate communication between cystic tumors of the peripheral type and the pancreatic duct in seven (88%) of eight cases of the peripheral type, which suggests high frequency of the communication in the peripheral type. For preoperative tissue diagnosis, EPB was shown to be a useful method to yield sufficient tissue materials for histopathological evaluation and may be used as an adjunction method to diagnose the intraductal extent of the tumorous lesion.

Adenocarcinoma, Mucinous↗
PubMed1992

Primary hyperparathyroidism in patients with multiple endocrine neoplasia type 1: experience by a single surgical team in Japan.

Nineteen patients were surgically treated for hyperparathyroidism associated with multiple endocrine neoplasia type 1 syndrome. Fourteen patients (74%) had removal of three or more parathyroid glands at the first operation, and five (26%) by removal of 2 1/2 or fewer glands. Two patients had recurrent hypercalcemia during the mean follow-up period of 65 months. One had a recurrence 10 years after subtotal parathyroidectomy. Reexploration in this patient revealed enlargement of the remaining tissue in the neck and an enlarged supernumerary gland in the aorticopulmonary window. The other patient had persistent hypercalcemia after removal of two hyperplastic parathyroid glands until after another 1 1/2 more glands were removed. After reoperation the patient was normocalcemic for 10 years before hypercalcemia was again noticed. The patient subsequently died from renal carcinoma metastases, which might have been the cause of the hypercalcemia before death.

Adult↗
PubMed1992

Risk factors associated with postoperative persistent hypertension in patients with primary aldosteronism.

BACKGROUND: Unilateral adrenalectomy was performed in 63 patients with primary aldosteronism. During a mean follow-up time of 4.1 years, none of the patients showed recurrence of hyperaldosteronism. However, 24 patients (38%) had persistent hypertension. The purpose of this study was to determine factors responsible for postoperative persistent hypertension. METHODS: A stepwise multivariate logistic regression analysis was performed to assess the combined predictive effects of the clinicopathologic variables. RESULTS: Age, sex, and pathologic findings were the best predictive factors of postoperative persistent hypertension. For a patient aged 50 years or more, the odds of persisting hypertension are 10.6:1, compared with those of a patient under 40 years of age. A male patient appears to have a greater chance of hypertension than a female patient; the odds ratio is 5.9:1. Persistent hypertension develops in patients with multiple adenomas or with an adenoma associated with macronodules more frequently than in those patients with a solitary adenoma; the odds ratio is 8.1. CONCLUSIONS: This study suggests that early surgical intervention at a younger age results in a more favorable outcome for patients with primary aldosteronism. The presence of macronodules in association with an adenoma is a cautious predictor of persistent hypertension after adrenalectomy.

Adrenalectomy↗