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Biomedical subjects

C R Teixeira

Publications and source records attributed to C R Teixeira.

At least 19 recordsLinked to original sources
PubMed2000

Biliary ascariasis after Roux-en-Y hepaticojejunostomy.

The authors report on a 6-year-old girl with biliary ascariasis after surgical treatment of a choledochal cyst and biliary-digestive tract reconstruction by Roux-en-Y hepaticojejunostomy. A precise diagnosis can be obtained by ultrasonography. Surgical treatment is required when clinical and endoscopic treatments fail. In countries in which this disease is endemic, biliary ascariasis should be considered in the differential diagnosis of cholangitis after surgery for hepaticojejunostomy.

Anastomosis, Roux-en-Y↗
PubMed1998

Isolation and partial characterisation of highly toxic lectins from Abrus pulchellus seeds.

The seeds of Abrus pulchellus, sub-specie tenuiflorus, belonging to the Leguminosae, subfamily Papilionoideae contain highly toxic lectins exhibiting specificity for galactose and galactose-containing structures. The toxins which agglutinate rabbit erythrocytes, present a highly toxic activity in vivo when injected in the peritoneal cavity of mice (LD50=31 microg x kg(-1)) or when tested with the microcrustacean Arthemia salina (LD50=3.5 microg x ml(-1)). The active fraction was purified in a single step, by affinity chromatography on a Sepharose-4B column. The purified toxins migrated as two single bands of Mr 63000 and 61500 Da (SDS-PAGE) and Mr 31500 and 29000 Da (SDS-PAGE with 2-mercaptoethanol), respectively, suggesting the presence of disulphide-bridge interchains as occurs in other plant toxins. The antibodies anti-A. pulchellus toxins did not recognize ricin preparation and only partial identity was observed to A. precatorius toxic lectins prepared in a similar way to ricin and A. pulchellus toxins.

Abrin↗
PubMed1995

Endoscopic treatment of submucosal invasive colorectal carcinoma with special reference to risk factors for lymph node metastasis.

A clinicopathological analysis of the risk factors for lymph node metastasis was performed in 177 patients with submucosal invasive colorectal carcinoma (CRC). The submucosal deepest invasive portion was histologically subclassified as well (W), moderately (M), or poorly (Por) differentiated. M type was further subdivided into moderately-well (Mw) and moderately-poorly (Mp) differentiated. The pattern of tumor growth was classified as polypoid growth (PG) and non-polypoid growth (NPG). Lymph node metastasis was detected in 21 (12%) of the 177 patients. Macroscopically, type IIc and IIa + IIc lesions showed a significantly higher incidence of lymph node metastasis (44% and 30%) than type IIa and I (4% and 8%). Regarding the histologic subclassification, Por and Mp lesions showed a significantly higher incidence of lymph node metastasis (67% and 37%) than W and Mw lesions (4% and 14%). NPG tumors showed a significantly higher incidence of lymph node metastasis (29%) than PG tumors (7%). The depth of submucosal invasion and lymphatic invasion (ly) were also significantly correlated with the incidence of lymph node metastasis (submucosal scanty (sm-s) invasion 4%, massive invasion 20%; ly(+) 23%, ly(-) 5%). None of the lesions with both sm-s invasion and of W or Mw type showed lymph node metastasis. These results indicate that submucosal invasive CRC with both sm-s invasion and of W or Mw type, which shows no ly, is the appropriate indication for endoscopic curative treatment.

Adenocarcinoma↗
PubMed1994

Proliferating cell nuclear antigen expression at the invasive tumor margin predicts malignant potential of colorectal carcinomas.

BACKGROUND: Proliferative activity may be a useful measure of malignant potential for a variety of tumors. Colorectal carcinomas contain multiple cell populations with different biologic properties. The invasive tumor margin is thought to represent the area with the highest metastatic potential. METHODS: Cell proliferation at the invasive tumor margin of 49 specimens of advanced colorectal carcinoma was assessed by immunohistochemical staining of proliferating cell nuclear antigen (PCNA) and compared with clinicopathologic findings. RESULTS: Colorectal carcinomas showed a wide range of PCNA labeling indexes (LI), reflecting variation in proliferative activity. The PCNA LI of tumors showing venous invasion (mean, 51.7% +/- 16.2%) was significantly higher than that of tumors without venous invasion (mean, 36.7% +/- 18.2%; P < 0.01). A strong association was observed between the PCNA LI and the metastatic potential of colorectal carcinoma; the PCNA LI of tumors showing lymph node metastasis (mean, 50.5% +/- 17%) was significantly higher than that of tumors without nodal involvement (mean, 39.8% +/- 18.5%; P < 0.05). In addition, the PCNA LI of tumors metastatic to liver (mean, 55.2% +/- 15.7%) was significantly higher than that of tumors without liver metastasis (mean, 41.0% +/- 17.6%; P < 0.01). Correlation with histologic features at the invasive tumor margin showed that a higher PCNA LI was associated with less differentiated tumors (P < 0.05). CONCLUSION: Evaluation of the PCNA LI at the invasive tumor margin may help identify colorectal carcinomas that have a higher malignant potential.

Antigens, Neoplasm↗
PubMed1992

Heterotopic pancreas diagnosed by endoscopic ultrasonography and endoscopic injection of ethanol to make a histologic diagnosis.

A gastric submucosal tumor in a 56-year-old man was presumed to be heterotopic pancreas on the basis of endoscopy and endoscopic ultrasonography. To obtain a histologic diagnosis we injected ethanol at the tumor site to create an artificial ulcer. This facilitated the removal of endoscopic biopsy specimens from the submucosal layer so that histologic examination could confirm the presence of heterotopic pancreatic tissue.

Choristoma↗
PubMed1991

Endoscopic therapy for gastric cancer in patients more than 80 years old.

We prospectively studied 17 gastric cancer patients who were more than 80 yr old, in whom endoscopic therapy was performed. The patients were divided into two groups: the first group included 13 patients in whom curative treatment was attempted, and in 11 (85%) a curative response was achieved. Two patients in this group showed a positive gastric biopsy after 1 and 2 yr, respectively, of therapy: one patient is under current treatment with laser therapy, and the other patient underwent surgery with resection of the stomach. The second group included four patients in whom treatment was aimed at prolonging survival or palliation, and in all four patients, a successful response was obtained. Therefore, our results demonstrate that endoscopic therapy is effective for the treatment of gastric cancer patients over 80 yr old.

Aged↗
PubMedDate not supplied

The clinical significance of the histologic subclassification of colorectal carcinoma.

According to the histologic features at the deepest level of tumor invasion (the tumor apex), we classified colorectal carcinomas as follows: well differentiated (W), moderately differentiated (M), and mucinous (Muc). By assessing its glandular configuration and cellular arrangement, the M type was further subdivided in to two different groups: moderately well differentiated (Mw) and moderately poorly differentiated (Mp) carcinomas. In our sample there were 56 W, 53 Mw, 20 Mp and 13 Muc tumors. The malignant potential of each tumor was evaluated by examining for the presence or absence of lymphatic invasion, venous invasion, lymph node metastases and liver metastases. In comparison with the other tumors, the Mp tumors proved to harbor the highest malignant potential, exhibiting a higher incidence of lymphatic invasion (95%, 19/20 of the cases), venous invasion (75%, 15/20 of the cases), lymph node metastases (80%, 16/20 of the cases), and liver metastases (40%, 8/20 of the cases). Colorectal carcinomas are composed of multiple cell populations with different biological and malignant properties, and through the histologic subclassification we could identify that Mp tumors have the highest potential to invade normal tissue and metastasize.

Antigens, Tumor-Associated, Carbohydrate↗
PubMedDate not supplied

Carcinoembryonic antigen staining patterns at the invasive tumor margin predict the malignant potential of colorectal carcinoma.

Immunohistochemical carcinoembryonic antigen (CEA) staining patterns at the invasive tumor margin were correlated with malignant potential in 64 advanced colorectal carcinomas. Twenty-two (34%) carcinomas showed an apical and 42 (66%) a cytoplasmic staining pattern. Carcinomas with a cytoplasmic pattern had a higher incidence of lymph node (71 versus 41%; p < 0.05) and liver (50 versus 23%; p < 0.05) metastasis and higher levels of serum CEA (p < 0.01) than those with an apical staining pattern. Nine of 11 recurrent tumors had a cytoplasmic pattern and 2 had an apical pattern (p < 0.05). Among carcinomas having the same degree of differentiation, those with a cytoplasmic CEA staining pattern were more aggressive. Six (55%) well-differentiated carcinomas with a cytoplasmic pattern metastasized to the liver while none with an apical pattern did (p < 0.05). Moderately differentiated carcinomas with a cytoplasmic pattern had a significantly higher incidence of lymph node metastasis than those with an apical pattern (77 versus 46%; p < 0.05). When colorectal carcinomas are examined at the invasive tumor margin, an evaluation of the CEA staining pattern is useful in recognizing carcinomas having a higher potential to metastasize and recur after curative surgery.

Adenocarcinoma↗
PubMedDate not supplied

Proliferating cell nuclear antigen expression correlates with the metastatic potential of submucosal invasive colorectal carcinoma.

To examine the malignant potential of submucosal invasive colorectal carcinoma, the relationship between proliferating cell nuclear antigen (PCNA) expression and clinicopathologic risk factors for lymph node metastasis was studied in 149 patients with submucosal invasive colorectal carcinoma. The depth of submucosal invasion was classified as scanty or massive. Histologic subclassification at the submucosal deepest invasive portion was done as follows: well differentiated (W), moderately well differentiated (Mw), moderately poorly differentiated (Mp) or poorly differentiated (Por). Tumor growth was divided into polypoid growth and nonpolypoid growth. The PCNA expression (labeling index, LI) was examined at the submucosal deepest invasive portion. The PCNA-LI of tumors showing lymph node metastasis (mean, 56.5 +/- 19.0%) was significantly higher than that of tumors without lymph node metastasis (mean, 41.5 +/- 19.3%; p < 0.01). The PCNA-LI of Mp tumors (mean, 57.7 +/- 16.5%) was significantly higher than that of W (mean, 38.5 +/- 19.0%; p < 0.05) and Mw (mean, 43.7 +/- 19.1%; p < 0.05) tumors. The PCNA-LI of tumors without adenomatous features (mean, 47.9 +/- 20.5%) was significantly higher than that of tumors with such features (mean, 37.1 +/- 17.1%; p < 0.05). The PCNA-LI was not correlated with other risk factors for lymph node metastasis, such as lymphatic invasion, depth of submucosal invasion, macroscopic type, and growth pattern. These results indicate that the PCNA-LI may be useful marker for predicting the potential metastases to lymph nodes in submucosal invasive colorectal carcinoma, while the proliferative activity of cancer cells correlates with the degree of the differentiation in the area of deepest invasion.

Antibodies, Monoclonal↗
PubMedDate not supplied

Flat-elevated colorectal neoplasms exhibit a high malignant potential.

The potential of flat-elevated colorectal adenomas to undergo rapid malignant transformation and progression to invasive carcinoma is still under discussion. Therefore, a total of 130 colorectal neoplastic lesions > or = 1 cm in diameter were examined after endoscopic or surgical resection. Lesions were macroscopically classified into three categories: (1) flat elevation (22 lesions), superficially elevated lesion with a smooth surface; (2) granular laterally spreading tumor (GLST; 26 lesions), laterally spreading aggregates of nodules forming a lesion with granular surface, and (3) polypoid (82 lesions), pedunculated, subpedunculated and sessile polyps. The adenomatous component showed a tubulovillous architecture in 9/26 (35%) of GLST and 18/82 (22%) of polypoid lesions, however none of the flat-elevated lesions had a villous component (p <0.01; p <0.05). Carcinoma was present in 17/22 (77%) flat elevations, 37/82 (45%) polypoid lesions and 11/26 (42%) GLST (p <0.05). None of the carcinomas arising in GLST and only 1/37 (3%) of those developing in polypoid lesions were invasive carcinomas, but 4/17 (24%) carcinomas arising in flat elevations showed submucosal invasion. Moreover, while all 5 noncancerous flat elevations showed severe atypia, 17/82 (21%) polypoid lesions and 5/26 (19%) GLST showed moderate atypia. In conclusion, flat-elevated colorectal neoplasms have a high malignant potential and the role of these lesions as precursors of colorectal carcinomas deserves greater emphasis.

Adenoma↗
PubMedDate not supplied

[Magnifying colonoscopy in the diagnosis of colorectal carcinoma invading the submucosa in familial adenomatous polyposis].

The development of colonoscopy with image magnification has enable to study the colonic mucosa in detail and to do differential diagnosis between neoplastic and non-neoplastic lesions from the observation of pit patterns. The results are comparable to stereomicroscopy being possible to predict the histologic diagnosis. In a patient with familial adenomatous polyposis magnifying colonoscopy was performed and this method demonstrated a wide variation of benign polypoid lesions and the morphological features of early colorectal cancer. In this patient, the evaluation by image magnification, together with indigo carmin 0.4% chromoscopy, showed a wide variety of lesions in the colon and rectum: laterally spreading tumor in the cecum, with IIIL + IV pits, subpediculate polyp in the transverse colon with approximately 2.0 cm diameter and IV + V pits, flat elevated lesions IIIL type, and in the sigmoid colon IIa + IIc lesion with V type of Kudo's classification were observed. The evaluation of pit patterns of the lesions in the transverse and sigmoid colon has enable to do the endoscopic diagnosis of the lesion with submucosal invasion.

Adenocarcinoma↗
PubMedDate not supplied

[Reutilization of disposable syringes: frequency and costs for the administration of insulin at home].

The present survey has the purpose to analyze the frequency and costs of the re-utilization of disposable syringes for insulin administration at home. One hundred and thirteen patients with diabetes assisted by a public hospital in a city in the interior São Paulo State, Brazil, were interviewed. The findings showed that regarding the studied population, the frequency of needles re-utilization varied from 1 to 20 times, and syringes re-utilization from 1 to 60 times. The greatest frequencies in the use of the same syringe or needle were of four times followed by three times. Re-utilizing the same syringe four times resulted in a cost reduction of 74.68%. The results pointed out the need for a legislation review as well as for new studies on the risks and benefits arising from this practice.

Costs and Cost Analysis↗