The postoperative outcome (including clinicopathologic features) in 19 patients with differentiated thyroid cancer of the isthmus was investigated to develop more appropriate surgical strategies for these lesions. The extent of thyroidectomy, including neck dissection, tumor size, nodal involvement, and other clinical features were evaluated. The incidence of intraglandular dissemination was about 16% in all patients. Analysis of regional node metastatic distribution revealed no definite metastatic pattern. In addition, there was no apparent correlation between tumor size and nodal involvement. Two of the six patients who underwent total thyroidectomy suffered permanent postoperative hypoparathyroidism. It is thus recommended that isthmusectomy, including an adequate edge of surrounding normal thyroid tissues of each lobe and modified or limited neck dissection when cervical nodes are palpably enlarged, is sufficient as an appropriate primary surgical procedure for differentiated carcinoma of the thyroid isthmus.

Adenocarcinoma↗

PubMedDate not supplied

Management of tracheal wall resection for thyroid carcinoma by tracheocutaneous fenestration and delayed closure using auricular cartilage.

BACKGROUND: In the case of advanced thyroid carcinoma invading the trachea, surgical procedures for tracheal resection are selected in relation to the degree of invasion. We created a tracheocutaneous fenestration that was later closed with a free auricular cartilage autograft. We present a simple and effective method for permanent closure of tracheostoma. METHODS: The surgical procedure for delayed closure consists of three steps: (1) preparing the hinge flap with additional undermining of the subcutaneous layer and the strap muscles; (2) removing a portion of the conchal cartilage from the auricle, which is easily performed with a semicircular skin incision along the anthelix of the ear; and (3) placing the conchal cartilage with its convex surface upward just over the sutured hinge flap layer. RESULTS: Under local anesthesia, we successfully employed this reconstructive procedure for 5 patients. Unfortunately, however, in one patient, we had to reopen the closed tracheocutaneous fenestration on the second postoperative day because of an acute problem that was independent of the closure surgery. Four patients remain in satisfactory condition for more than 2 years since the closure of tracheostoma. CONCLUSIONS: The auricular cartilage free graft is a relatively simple procedure which supplies tracheal wall skeletal support for the permanent closure of the tracheocutaneous fenestration.

Aged↗

PubMedDate not supplied

Subword activation in reading Japanese single Kanji character words.

Kanji are categorized into four types based on the combination of "subword validity" (when the right phonemic radical represents the same On reading as the whole Kanji character) and "radical-neighbor consistency" (when the whole Kanji character represents the same On reading with all its neighbor characters). The study demonstrated that both subword validity and radical-neighbor consistency affect naming latencies and error rates for relatively high-frequency Kanji character words. Moreover, both analytic and holistic decoding processes, which correspond to subword and whole-character activation, are used in the naming of Japanese single Kanji character words. Accounts of the findings by dual-route and connectionist models are discussed.

Cognition↗

PubMedDate not supplied

Radioimmunoassay for dexamethasone 17,21-dipropionate and its metabolites in plasma and urine after topical application.

A sensitive radioimmunoassay for dexamethasone 17,21-dipropionate and its four metabolites in human plasma and urine has been developed using single anti-dexamethasone antiserum. The antiserum was obtained by immunizing rabbits with dexamethasone-3-oxime-bovine serum albumin conjugate. All of the endogenous steroids tested cross-reacted less than 0.07%. Before radioimmunoassay, dexamethasone 17,21-dipropionate and dexamethasone 17-propionate were hydrolyzed to dexamethasone, and 6 beta-OH-dexamethasone 17-propionate was hydrolyzed to 6 beta-OH-dexamethasone in 3% ammonia/methanol at 5 C for 16 h. A standard curve was established with a useful range between 0.005 and 2 ng in the case of dexamethasone, between 0.05 and 5 ng in the case of 6 beta-OH-dexamethasone. Measurement of plasma concentrations and percent urinary excretion of the metabolites in healthy men was performed following occlusive dressing of dexamethasone 17,21-dipropionate cream and ointment. The main metabolites in plasma were dexamethasone 17-propionate and dexamethasone, which increased gradually and reached maximum levels (160-200 pg/mL) at 24-32 h after application. The major metabolites observed in urine were 6 beta-OH-dexamethasone 17-propionate and 6 beta-OH-dexamethasone. Total percentage of their urinary excretions within 72 h after application amounted to 0.28-0.50% of the dose administered.

Administration, Topical↗

PubMedDate not supplied

Increase in endothelial cell density before artery enlargement in flow-loaded canine carotid artery.

To investigate the morphologic basis of blood flow-dependent adaptive vascular enlargement, we quantitated endothelial cell density, dimensions, and structure in canine carotid arteries that were flow-loaded for 4 weeks, i.e., just before the development of significant adaptive enlargement. Increased flow was produced in the right common carotid artery of seven adult beagle dogs by an arteriovenous shunt to the right external jugular vein. The left common carotid artery was used to produce sham-operated controls. Five additional animals were used to produce sham-shunted controls, and two dogs were used as nonoperated controls. The blood flow rate (BFR) and wall shear rate (WSR) were markedly increased immediately after anastomosis in the proximal segment of the shunted artery (BFR = 719 +/- 142 ml/min, WSR greater than 4127 +/- 1002/sec) and after 4 weeks (BFR = 628 +/- 157 ml/min, WSR greater than 2919 +/- 388/sec) compared to the same artery before anastomosis (BFR = 154 +/- 50 ml/min, WSR = 904 +/- 314/sec, p less than 0.01 x 10(-3) for both comparisons) and to the contralateral control artery after 4 weeks (BFR = 365 +/- 110 ml/min, WSR = 2136 +/- 876/sec, p less than 0.01 and p less than 0.05, respectively, compared to the shunted side). In the shunted artery, endothelial cell density was markedly increased (6.15 +/- 0.68 x 10(3) cells/mm2 compared to 3.33 +/- 0.70 x 10(3) cells/mm2 for the controls, p less than 0.001). Endothelial cells on the high flow side were markedly narrowed in both axial and circumferential directions, but were radially thickened; nuclei became prolate-spheroid in shape. On the control side, cells were relatively flat and thin. We conclude that elevated wall shear stress induces an early increase in endothelial cell number and that this increase precedes the development of significant blood flow-dependent vascular enlargement.

Animals↗

PubMedDate not supplied

Clinical experience with temporary vena cava filters.

An experience with temporary filter placement, which seems to be safe and effective for temporarily preventing pulmonary embolism, is reported. Since October 1997, six patients had temporary filters. There were two men and four women, with a mean age of 37 years. Three filters were placed at the infrarenal inferior vena cava, two at the suprarenal inferior vena cava, and one at the superior vena cava. All filters were placed before various surgical interventions. During filter placement, anticoagulation therapy was routinely performed. There were no complications at and during filter placement. No pulmonary emboli occurred during surgical intervention. All filters were successfully removed, two of which were exchanged for permanent filters. All patients are alive and well without recurrent deep vein thrombosis and/or pulmonary emboli during a follow-up period of 11 to 25 months. Although this experience is small, temporary filter placement is safe and effective for short-term prevention of pulmonary emboli even in older patients or those with malignant disease. Veins of the upper part of the body may be more favorable than the femoral vein for insertion of a temporary filter. Temporary filters can be safely placed not only at the infrarenal inferior vena cava, but also at the suprarenal inferior vena cava or superior vena cava.

Adolescent↗

PubMedDate not supplied

Freeze-etch visualizations of some elements in the stria vascularis.

A quick-freeze, deep-etch study was made to observe the three-dimensional aspect of both membranes and organelles in the stria vascularis of the guinea pig. Our replicas showed various membrane characteristics of the vesicles, e.g., a clathrin basket on the inner surface membrane, aggregation of membrane particles on the protoplasmic fracture face, and regularly arranged surface protuberances on the outer surface membrane. In the cell processes of marginal cells, there were not only bundles of microtubules but also another type of fibril. Many gap junctions were observed between marginal, intermediate, and basal cells. In some replicas, the inner surfaces of the gap junctions were covered with particle protrusions with some ordered arrangements. The functional roles of these elements in the stria vascularis are discussed.

Animals↗

PubMedDate not supplied

c-myc gene mutation in gastric mucosa-associated lymphoid tissue (MALT) lymphoma and diffuse large B-cell lymphoma.

The c-myc gene is involved in important cellular processes, including cell proliferation, differentiation, and apoptosis. We analyzed mutation of the c-myc gene in 51 patients with gastric lymphoma [27 patients with low-grade mucosa-associated lymphoid tissue (MALT) lymphoma, 11 with high-grade MALT lymphoma, and 13 with diffuse large B-cell lymphoma (DLL)], by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis. We also evaluated the relationship between mutation of the c-myc gene and regression of low-grade MALT lymphoma after Helicobacter pylori (H. pylori) eradication. Mutation in exon 2 of the c-myc gene was present in 2 of 20 (10%) patients with low-grade MALT lymphoma, in 1 of 7 (14%) patients with high-grade MALT lymphoma, and none of 10 patients with DLL. The 3 patients who had mutations of the gene, showed different patterns of mobility shift, suggesting different mutations. In addition, 15 patients with low-grade MALT lymphoma received anti-H. pylori therapy. All the patients achieved eradication. Nine of the 15 (60%) patients with low-grade MALT lymphoma showed complete regression (CR), 3 (20%) showed partial regression (PR), and 3 (20%) showed no change (NC). One of the 9 (11%) CR patients had a mutation of the c-myc gene. None of the 3 PR and 3 NC patients had mutation of the gene. There was no significant difference between the frequencies among the c-myc gene mutation in CR, in PR and in NC patients. These data suggest that mutation of the c-myc gene may not be commonly associated with development of gastric MALT lymphoma and DLL, and may not be associated with regression of low-grade MALT lymphoma after H. pylori eradication.

Anti-Ulcer Agents↗

PubMedDate not supplied

Microsatellite instability at D18S61 is associated with no regression of gastric mucosa-associated lymphoid tissue lymphoma after Helicobacter pylori eradication.

Recent studies have shown 70-80% of gastric low-grade mucosa-associated lymphoid tissue (MALT) lymphomas regressing in response to eradication of Helicobacter pylori (H. pylori). Genetic mechanism of regression of gastric MALT lymphoma after H. pylori eradication remains unclear. To clarify the issue, we evaluated microsatellite instability (MSI) at 12 microsatellite loci in 15 patients with gastric low-grade MALT lymphoma, who received eradication therapy of H. pylori. H. pylori infection was observed in all the patients. After eradication therapy of H. pylori, patients were observed for a median of 21 months (range, 6-49 months). Eradication was achieved in all the patients. Nine of the 15 (60%) patients showed complete regression (CR), 3 (20%) partial regression (PR), and 3 (20%) no change (NC). MSI was detected in 3 of the 15 (20%) patients with low-grade MALT lymphoma. Compared with response to eradication therapy of H. pylori, MSI was detected in 1 of the 12 (8%) CR and PR patients, and in 2 of the 3 (67%) NC patients. Especially, MSI at D18S61 was detected in 2 of the 3 (67%) NC patients but in none of the 12 CR and PR patients. There was a significant difference between frequency of MSI at D18S61 in NC patients and that in CR and PR patients (p<0.05). These data suggest that MSI at D18S61 may be associated with lack of regression of gastric MALT lymphoma after H. pylori eradication.

Anti-Ulcer Agents↗

PubMedDate not supplied

Microsatellite instability of each tumor in sporadic synchronous multiple colorectal cancers.

The purpose of this study was to elucidate microsatellite instability (MSI) and p53 expression for each tumor in cases with sporadic synchronous multiple colorectal cancers. Twenty-nine patients with sporadic synchronous multiple colorectal cancer were examined. There were sixty-five tumors, all of which indicated adenocarcinoma histopathologically. The MSI was assessed using six microsatellite markers (BAT26, BAT40, D2S136, D5S346, D11S922, D17S250). Tumors with two or more positive loci were determined to be MSI-H (high-frequency MSI), tumors with one positive locus were designated as MSI-L (low-frequency MSI) and tumors lacking apparent instability were designated as MSS (microsatellite stable). In addition, overexpression of p53 protein was examined using immunohistochemical (IHC) methods for each tumor. The DO-7 monoclonal antibody was used in the IHC assessments. The following results were obtained: i) there were nine patients who indicated MSI-H at the first tumor (1-H group) and 20 patients who had MSI-L or MSS at the first tumor (1-LS group). ii) The ratio of cases that indicated MSI-H at the second tumor and beyond in the 1-H group was 88.9% (8/9), which was significantly higher than that of the 1-LS group (30.0%, 6/20) (p=0.0021). iii) The frequency of cases with the right-sided colon in the 1-H group (61.9%) was significantly higher than that of the 1-LS group (27.3%) (p=0.0073). In addition, a significant difference was noted in terms of the ratio of cases with poorly differentiated adenocarcinoma or mucinous carcinoma between the two groups [1-H group (19.0%) vs 1-LS group (0%), p=0.0028]. Furthermore, no distinct relationship between MSI status and p53 overexpression was obtained. In conclusion, we think that sporadic synchronous multiple colorectal cancers should be divided into two types; one type that indicates multiple occurrence of MSI-H consecutive tumors and another type that shows multiple occurrence irrespective of MSI.

Adenocarcinoma↗

PubMedDate not supplied

p53 mutation found to be a significant prognostic indicator in distal colorectal cancer.

There has been few reports describing that the prognostic significance of p53 alteration in colorectal tumors depended on the site of origin. Therefore, in this study, we examined whether there is a valid association between the p53 alterations and the prognosis of colorectal cancer patients, especially distal colorectal cancer cases. Tumor samples were collected from 110 patients resected for colorectal cancer between 1989 and 1997. The entire coding region of the p53 gene was analyzed by automated direct sequencing. In addition, the DO-7 monoclonal antibody was used in the immunohistochemical (IHC) assessments. By the Cox univariate analyses in all tumors, Dukes' stage, lymph node metastasis, liver metastasis, p53 mutation and p53 protein overexpression were significant predictors of survival. The cases without p53 mutation showed significantly improved prognosis compared to the cases with p53 mutation (p = 0.0085). In distal tumors, Dukes' stage, liver metastasis, p53 mutation and p53 protein overexpression were significant predictors of survival. Multivariate analysis of all tumors, p53 mutation and liver metastasis were independent indicators of poor survival (p = 0.0223 for p53 mutation, p = 0.0254 for liver metastasis). Also in distal tumors, p53 mutation was an independent indicator (p = 0.0011). Furthermore, the relative risk associated with p53 mutation in distal tumors was much higher than that in all tumors (8.260 vs. 1.796). However, p53 protein overexpression was not an independent indicator of survival in all tumors as well as distal tumors (p = 0.1918 in all tumors, p = 0.0607 in distal tumors). In proximal tumors, p53 mutation was not an independent indicator (p = 0.6673). We think that p53 mutation is a very useful prognostic indicator when distal colorectal cancers are considered.

Aged↗