Unravelling the tunable exchange bias-like effect in magnetostatically-coupled two dimensional hybrid (hard/soft) composites.

Hybrid 2D hard-soft composites have been fabricated by combining soft (Co73Si27) and hard (NdCo5) magnetic materials with in-plane and out-of-plane magnetic anisotropies, respectively. They have been microstructured in a square lattice of CoSi anti-dots with NdCo dots within the holes. The magnetic properties of the dots allow us to introduce a magnetostatic stray field that can be controlled in direction and sense by their last saturating magnetic field. The magnetostatic interactions between dot and anti-dot layers induce a completely tunable exchange bias-like shift in the system's hysteresis loops. Two different regimes for this shift are present depending on the lattice parameter of the microstructures. For large parameters, dipolar magnetostatic decay is observed, while for the smaller one, the interaction between the adjacent anti-dot's characteristic closure domain structures enhances the exchange bias-like effect as clarified by micromagnetic simulations.

Adenosine deaminase in the diagnosis of tuberculous pleural effusions. A report of 218 patients and review of the literature.

The activity of adenosine deaminase in the pleural fluid of 218 consecutive patients was studied. According to the etiology of exudative pleural effusions, the patients were divided into the following five groups: (1) tuberculosis; (2) lung cancer; (3) pneumonias; (4) miscellaneous; and (5) idiopathic. Patients with pleural tuberculosis presented significantly higher ADA activity than patients with nontuberculous pleural effusions (p less than 0.0001). The results indicated that in a population with a relatively high prevalence of tuberculosis, the analysis of ADA levels in pleural effusions constitutes a useful marker for the diagnosis which, in addition, can be made quickly and cheaply. Additionally, a comprehensive review of the literature on the role of ADA in the diagnosis of tuberculous pleural effusions is presented.

Molecular analysis of p53 tumor-suppressor gene and microsatellites in preneoplastic and neoplastic lesions of the colon and esophagus.

Mutations in exons 4-8 of the p53 gene by the PCR-SSCP analysis in preneoplastic and neoplastic lesions of the colon (n=11) and esophagus (n=18) were screened. p53 overexpression by immunohistochemistry in 11 colonic lesions and 13 microsatellites, in all the patients (n=29), were also studied. A positive result concordancy between the three techniques was found in 1 adenoma and 2 adenocarcinomas of the colon, each with loss of heterozygocity of microsatellites. Metaplastic lesions of esophagus showed biallelic mutations and low frequency of microsatellite alterations. The relationship between genetic alterations in p53, microsatellites and type of colon and esophageal lesions is discussed.

Production of platelet-derived growth factor by human lung cancer.

The production of platelet-derived growth factor (PDGF) was studied in small cell lung carcinoma, lung squamous carcinoma and lung adenocarcinoma cell lines, and in seven human lung tissues obtained from each type of lung cancer. By indirect immunofluorescence, PDGF was detected in all the cell lines. Likewise, five out of seven biopsies derived from patients with adenocarcinoma and squamous carcinoma, and four out of seven specimens with small cell carcinoma displayed a positive pattern for PDGF. In addition, lung carcinoma cell lines expressed both PDGF-A and PDGF-B/sis genes, as judged by Northern blot analysis. Biologically active, serum-free conditioned media obtained from all three cell lines stimulated the incorporation of [3H]thymidine into quiescent BALB/c-3T3 cells. This effect was abolished when IgG-PDGF antiserum was used. These findings suggest that an abnormal expression of PDGF occurs in the three more frequent types of lung cancer, which can play a potential role in neoplastic transformation and uncontrolled cell growth.

Tuberculosis of the larynx: clinical aspects in 19 patients.

Laryngeal tuberculosis continues to exist in spite of extensive tuberculosis eradication campaigns. We present 19 cases of laryngeal tuberculosis seen in our institution between 1982 and 1987. From the clinical findings it is clear that the localization of the lesions has changed since the preantibiotic era. Today the spread appears to be mainly via lymphatic and hematogenic routes, as opposed to the direct spread more common previously. The fibrosis caused by the lesions is incapacitating and frequently requires surgical correction.

[Primary hydatic cyst of the tail of the pancreas. Segmental portal hypertension]. / Quiste hidatídico primitivo de cola de pancreas. Hipertensión portal segmentaria.

An uncommon purulent primitive hydatic cyst of the pancreatic tail with segmental portal hypertension and gastric varix is reported. Recognition of gastric varix on angiography and immunological diagnosis of hydatidosis clarified the ethiology of hematemesis. Surgical resection of the spleen and pancreas tail cured the patient's recurrent hemorrhages.

[Endoscopic diagnosis of duodenal and jejunal diseases]. / Diagnóstico endoscópico de las afecciones del duodeno y yeyuno.

We presented and studied the endoscopic diagnosis of the duodenal ulcer, duodenal tumors and duodenal bleeding. Duodenal Ulcer is classified according as location, form and evolutive stage. Duodenal tumors are divided in polyps, primitive tumors, pancreas anomaly and lymphoma. Duodenal bleeding can be diagnosed according its cause (inflammatory, tumors vascular and traumatic). It is emphasized the importance of the indications and methods of the enteroscopy. We show our experience in 313 duodenal ulcers cases and 98 enteroscopic diagnosis.

[Simple-blind clinical study with sublingual lorazepam vs. injectable diazepam as premedication in colonoscopies]. / Estudio clínico simple ciego con lorazepan sublingual vs. diazepan inyectable como premedicación en colonoscopías.

Those patients premedicated at least 90 minutes before coloscopy, with sublingual lorazepam, showed improved sedative effect, better tolerance and collaboration? Less discomfort and pain when air was, as usually insuflated, as compared with patients receiving intramuscular diazepam. Doctor's opinion coincided with the before mentioned preference for sublingual lorazepam prescribed at least 90 minutes before the endoscopic procedure. No adverse side effects were pointed out.

[Primary gastric plasmacytoma. Presentation of a case]. / Plasmocitoma gástrico primario. Presentación de un caso.

A case of primary gastric plasmacytome is presented. The difficulties of the endoscopic diagnosis, including the citology and the biopsy, are emphasised.

[Catarrhal stomatitis of the gastric stump. Histological changes]. / Estomatitis catarral del muñón gástrico. Alteraciones histológicas.

The prospective investigation here presented tries to show the histologic changes produced in the endoscopic mucosal erythema zone of the gastric stump, which is the largest exposition and reactivity site to which the duodenal-biliary reflux damages. 56 clinically asynthomatic patients have been studied through directed biopsy. The observed results are: great prevailing of chronic gastritis and a high percentage of intestinal metaplasia which, in both cases are in close correlation with the age of the patient and not with his surgical age. There is not any relation either with age or intensity in the different degrees of dysplasia. We came to the conclusion that the erythema does not constitute by it self a histologic perfile different from the rest of the remaining gastric stump.

[Percutaneous transhepatic biliary drainage in obstructive jaundice]. / Drenaje biliar transhepático percutáneo en las ictericias obstructivas.

PTC was performed in 86 patients with obstructive jaundice, between February/80--March/81 diagnosing 20 cases of the hepatic hilium carcinoma, 14 of pancreatic carcinoma, and 2 multiplex abscess of the liver. PTC-D was successfully attempted on 16 patients, catheterizing the intrahepatic biliary tree in 15 and maintaining a good biliary flow in 10 of them. The catheter was on the correct position into the biliary tree in 6 patients, and the drainage continued for 7-20 days. General improvement was obtained in 83.33%, itching decreased in 40% and disappeared in 60%, cholestasis was reduced in 100% and sepsis in 75%. Complications of the technique were: pain during the introduction of the guide wire (18.75%) and transitory hemobilia (31.21%). PTC-D seems to be a procedure with a precisely indication in every transitory obstructive jaundice, in order to put the patient in better conditions to a definitive therapy: 1) Surgery 2) Prosthesis 3) External-internal biliary drainage.

[Intermediate gastric cancer]. / Cancer gástrico intermedio.

Gastric Cancer comprises two basic types: Advanced Gastric Cancer (A.G.C.) and Early Gastric Cancer (E.G.C.). A.G.C. extends beyond the proper muscle layer with a 5 to 17%, five years survival rate after surgery. E.G.C. does not extend beyond the submucosa (with or without metastasis to regional lymph nodes) and has a 80 - 95% five years survival rate. Intermediate Gastric Cancer, PM G.C. (Gastric cancer of the proper muscle layer) does not surpass the proper muscle layer and offers a five years life expectance of near 60% after adequate surgical treatment, with peculiar features in radiology, endoscopy and evolutivity. We report a case of PM G.C., "depressed" and "protruded". The proper muscle layer was invaded by the depressed lesion". Both lesions were continguous.

[Transjugular hepatic biopsy. Technic and indications in hepatobiliary diseases]. / La biopsia hepática transyugular. Técnica e indicaciones en las enfermedades hepatobiliares.

The result of 25 transjugular liver biopsies are described. The indications of this technique were: Abnormal blood clotting 65%. Failure of previous percutaneous biopsy 15%. Requirements of suprahepatic venography and or manometry. Perforation of the hepatic capsule was evident in three patients when contrast medium injected after the biopsy escaped under the capsule but without evidence of bleeding. The transjugular liver biopsy is not easy but safe and preferable technique in the management of selected patients.

[Evaluation of Ig and muramidase (lysozyme) in unspecified chronic duodenitis (bulbitis)]. / Valoración de Ig y muramidasa (lisozima) en la duodenitis crónica inespecífica (bulbitis).

In 158 patients with symptoms of non ulcerative dyspepsia, endoscopic, histologic and immunohystochemical studies were performed over three years with the aim of investigating the immunological involvement in the Chronic non specific Duodenitis (CND). After excluding 112 patients with associated pathologies of those not fulfilling technics requisites, a population of 46 subjects was selected and subsequently it was subdivided into four groups. A group of 15 patients with histologically normal duodeno served as control; the rest (31 patients) were grouped according to duodenal compromise into three groups of minor-major severity; Grade 1 (n=12); Grade 2 (n=12); Grade 3 (n=7). The number of immunoglobuline producing cells by mn2 of mucosal area and semiquantitative evaluation of mononucleated cells with cytoplasmatic activity to hydrolitic enzymes (lysozyme or muramidase) were compared among the 4 sub-groups. It was observed a variation in the immunoglobulines rate among controls (IgA: M: G=82, 52: 11, 01: 6,45) regarding the most severe degree (61, 56: 27,30: 11,14). The increase of IgMy G compared with controls was highly significant (p is less than 0.001) and it was noted a correlative IgA diminution. The contribution of hydrolitic enzymes through the presence of "activated" histiocytes was maximal in the most degree-coinciding with the increase of IgM and IgG. This findings indicated that a marked local activation of the Immunitary System type B is observed in the Chronic Nonspecific Duodenitis and its increment, expressed as quali-quantitative variations of the different immunologlobulines and muramidase producing cells, should have lythic activity in the highest degrees. We conclude, proposing this disease as a model of immunological aggression which affects bulbar mucosae.

[Misoprostol and cimetidine in the treatment of active duodenal ulcer. Multicenter, double-blind, clinico-endoscopic study. The Argentine experience]. / Misoprostol y cimetidina en el tratamiento de la úlcera duodenal activa. Estudio clínico-endoscópico, multicéntrico, doble ciego. Experiencia Argentina.

Ten Argentine centers participated in this cooperative trial. One hundred and sixteen patients with endoscopically proven duodenal ulcer entered the study and were randomly assigned to receive either Misoprostol 800 micrograms or Cimetidine 1200 mg, q.i.d. per day, during four weeks of treatment. Patients were allowed to take Amphogel tablets for relief of ulcer pain when necessary, and clinical, lab-tests and adverse effects were evaluated weekly. Ninety-nine patients (Misoprostol 54, Cimetidine 45) completed the study and were evaluable. Success/failure criteria were based on endoscopically documented complete healing at the end of treatment period. Healing rate of four week was 85.2 per cent (46/54) for Misoprostol and 75.5 per cent (34/45) for Cimetidine, with no statistically significant difference. It is concluded that Misoprostol and Cimetidine are highly effective and safety in the healing of active duodenal ulcer. Misoprostol is a new therapeutical alternative for the treatment of duodenal ulcer patients.

Electron microscopic appearances of chronic nonspecific duodenitis (bulbitis).

The diagnosis of CND cannot be improved by electron microscopy. The normal duodenal cap and CND have similar ultrastructural appearances on guided endoscopic biopsy.

G-cells and gastrinaemia in chronic nonspecific bulbitis.

Chronic nonspecific bulbitis (CNB), the number of G-cells in the antrum and the level of serum gastrin were unrelated in a group of 24 patients. Gastrin may be produced by cells outside the antrum or by a few but hyperactive antral G-cells.