La "cultura de la sobrevivencia" y la salud pública internacional en América Latina: la Guerra Fría y la erradicación de enfermedades a mediados del siglo XX / The "culture of survival" and international public health in Latin America: the Cold War and the eradication of diseases in the mid-twentieth century

Este artículo analiza las principales campañas promovidas por agencias internacionales y organismos nacionales de salud dirigidas a erradicar enfermedad infecciosas en el ámbito rural latinoamericano de los años 1940 y 1950. Las dimensiones políticas del periodo han sido estudiadas pero todavía se ha prestado poca atención a sus dimensiones sanitarias. Este trabajo propone el concepto de "cultura de la sobrevivencia" para explicar los problemas de la salud pública oficial de Estados con políticas sociales limitadas que no permitieron el ejercicio de la ciudadanía. La salud pública, como parte de esta cultura de la sobrevivencia, buscaba ser una solución temporal sin enfrentarse a los problemas sociales que originaban las infecciones y dejó un legado en la salud pública de la región.

This article analyzes the main campaigns run by international agencies and national health bodies to eradicate infectious diseases in rural Latin America in the 1940s and 1950s. The political dimensions of the period have been studied but there has been little attention as yet to the health dimensions. This article proposes the concept of a "culture of survival" to explain the official public health problems of states with limited social policies that did not allow the exercise of citizenship. Public health, as part of this culture of survival, sought a temporary solution without confronting the social problems that led to infections and left a public health legacy in the region.

A Clinical and Immunohistochemical Study on Gastrointestinal Stromal Tumor / 대한소화기학회지

BACKGROUND/AIMS: As the relationship between gastrointestinal stromal tumors (GIST) and interstitial cells of Cajal had become clear, GIST is defined as CD117 positive mesenchymal tumors, and recognized as a new distinct entity among mesenchymal tumors presenting as gastrointestinal submucosal tumors (SMT). To evaluate GISTs in the category of SMTs, we analyzed mesenchymal SMTs immunohistochemically and clinicopathologically. METHODS: Forty-five patients with mesenchymal SMTs, who received surgical or endoscopic resection were retrospectively analyzed for clinical parameters. Immunohistochemical staining for CD117, CD34, NSE, SMA, and S-100 was also performed. RESULTS: Among 45 tumors, 41 (91.1%) expressed CD117 and were diagnosed as GIST. The most frequent location was the gastric body. Except esophageal location (73.3%), GISTs accounted for 100% of SMTs in the gastrointestinal tract. The mixed myoid-neural differentiated type and the spindle cell shape were most common. Metastasis was observed in 5 patients (11%). All of them had tumors larger than 5 cm and died. Their mean survival was 4.6 months. CONCLUSIONS: GIST accounted for majority (91.1%) of SMTs. The presence of metastasis and tumor size at the time of diagnosis indicate poor prognostic factors. Immunohistochemical study is necessary for exact diagnosis of GIST.

Fine Needle Aspiration Cytology (FNAC) of Gastrointestinal Stromal Tumor: An Emphasis on Diagnostic Role of FNAC, Cell Block, and Immunohistochemistry

Recently the origin of gastrointestinal stromal tumors (GISTs) is thought be the interstitial cells of Cajal or primitive stem cells. This study was performed to evaluate the roles of fine needle aspiration cytology (FNAC), cell block preparation, and immunohistochemistry in the diagnosis of GISTs. Nine cases of GIST in which FNAC was performed were included in this study. Cytologically, the tumor cells characteristically occurred in closely packed cohesive tissue fragments with high cellular density often in bloody background. The tumor cells often formed fascicles with parallel, side-by-side arrangements of the nuclei. Histologically, GISTs were highly cellular spindle or epithelioid tumor with basophilic appearance. Immunohistochemically, GISTs were c-kit positive in all of nine cases, CD34 positive in seven, focally SMA positive in two, and S-100 and GFAP negative in all. Both histologic and cell block sections showed the same histologic and immunohistochemical features. Cytomorphologically GISTs show a broad morphologic spectrum but rarely a significant nuclear pleomorphism and the assessment of malignant potential is difficult based on cytology alone. However, in the appropriate clinical and radiologic setting, a confident diagnosis of primary or metastatic GIST can be established by FNAC, cell block, and immunohistochemistry.

Utility of Thyroid Transcription Factor-1 and Cytokeratin 20 in Identifying the Origin of Metastatic Carcinomas of Cervical Lymph Nodes

The identification of primary location of a metastatic tumor is a difficult diagnostic problem and sometimes can be facilitated by the use of immunohistochemical markers. Thyroid transcription factor-1 (TTF-1) is a 38-kDa nuclear homeodomain transcription factor that is expressed specifically in lung or thyroid neoplasms. Cytokeratin 20 (CK20) is a 46-kDa low-molecular-weight cytokeratin that shows restricted expression in adenocarcinomas of the gastrointestinal tract (GIT) and transitional cell carcinomas of the urinary tract. We studied the immunohistochemical expression of TTF-1 and CK20 in 68 metastatic carcinomas in cervical lymph nodes. The primary sites were the lung in 29 cases, stomach in 13, colorectum in 3, and other sites in 23. TTF-1 expression was detected in 69.0% of metastatic lung carcinomas and none in metastatic GIT carcinomas, whereas CK20 expression was detected in 68.8% of metastatic GIT carcinomas and none of metastatic lung carcinomas. TTF-1 had a specificity of 0.95 and a sensitivity of 0.69 for metastatic lung carcinoma, whereas CK20 had a specificity of 1.00 and a sensitivity of 0.69 for metastatic GIT carcinoma. These results indicate that TTF-1 and CK20 should be the first choice as a component of antibody panel to prove or to exclude the lung and GIT origin, respectively, especially in patients presenting with metastatic carcinomas of unknown primary site.

CA 50: a tumor marker for gastrointestinal malignancies.

Efforts to find the ideal tumor marker, together with the advanced knowledge of the carbohydrate expression by cancer and the development of monoclonal antibody technology have facilitated the generation of many new tests used in clinical oncology. CA 50, a novel cancer-associated carbohydrate marker, is detected by the C 50 antibody that has been obtained by immunization of mice with a human colorectal adenocarcinoma cell line. This antibody that defines CA 50 reacts with both the afucosyl form of sialylated Lewis(a) carbohydrate moiety and sialylated Lewis(a) moiety which is also the antigenic epitope in the CA 19-9 assay. CA 50 is not organ-specific and its elevated levels in serum can be observed in a variety of malignancies, especially gastrointestinal cancers. In contrast to CA 19-9, high CA 50 levels can also be seen in malignant tumors outside the digestive tract. The expectation, that CA 50 might be positive in the Lewis negative patients who cannot synthesize CA 19-9, is supported by the histoimmunologic study. However, in serum determination close correlation between CA 50 and CA 19-9 has been observed even in patients who have Lewis negative phenotype. In clinical application, CA 50 is marginally beneficial for the diagnosis, but very useful for the follow-up of patients with pancreatic cancers. It gives results rather similar to CA 19-9. Moderately high serum levels of CA 50 can also be seen in benign hepatobiliary diseases, especially in jaundice cases. Therefore, this should be considered in order to obtain the most advantage of the marker. For other gastrointestinal cancers, CA 50 in combination with other previously defined markers may give additional information for the evaluation of some patients with colorectal, biliary, or gastric cancers. At present, there are many new emerging tumor markers used in clinical oncology. Increasing our knowledge about these markers, their capabilities and limitations will enable us to use them effectively in the evaluation of cancer patients.

Bauhinia purpurea agglutinin (BPA) binding sites in human gastrointestinal tract.

The binding of biotinylated BPA to parraffin sections of 18 normal gastrointestinal tract mucosa, 5 nonneoplastic polyps (NNP), 12 adenomas, and 59 carcinomas was studied by using avidinbiotin peroxidase complex (ABC) technique. In normal mucosa BPA appeared to bind both mucus and nonmucus glycoproteins but goblet cell mucus showed a decrease in binding and increase in binding of nonmucus glycoproteins as the cells lose their differentiation. BPA showed characteristic binding patterns in adenoma and carcinoma that differed from the pattern in normal mucosa. In normal mucosa linear binding to the apical cytoplasm in the columnar cells of the surface epithelium was observed, whereas in adenomas and carcinomas, in addition to the linear binding to the apical cytoplasm, diffuse cytoplasmic and granular deposits in the supranuclear, paranuclear or infranuclear zones were seen. Our findings suggest that BPA binding patterns in normal and neoplastic mucosa are related to the degree of cellular differentiation. In the process of malignant transformation the carbohydrate distribution undergoes progressive changes through the adenoma carcinoma sequence. These changes are related to the degree of dysplasia in adenomas and to the degree of differentiation in carcinomas.