PubMed Health⌕ Search

Biomedical subjects

L Ortega

Publications and source records attributed to L Ortega.

70 records · Page 4Linked to original sources
PubMed1987

[Biochemical complications of experimental vesico-sigmoidostomy].

Three experimental models of vesico-sigmoidostomy are studied (model-1, end to side V-S plus urethral ligation, model-2, end to end V-S, in "Y of Rous" plus urethral ligation and model-3, vesico-sigmoidoplasty), with aim of reproducing chemical imbalance observed in human subjects with ureterosigmoidostomy. Authors have evaluated clinical biochemical (serum acido-base balance, Cl, Na+, K+, BUN, creatinine, ammonia and albumin), and histologic variables in the first, third and fifth month after operation in 225 rats. Animal of model-1 presented more frequently than model-2 and model-3, alterations (hyperchloraemic acidosis, uraemia, hyperammonemia and hypoalbumin) as well as affectation of upper urinary system for acute or chronic pyelonephritis.

Animals↗
PubMed1986

Antral gastrin-producing G-cells and somatostatin-producing D-cells in peptic ulcer.

The number of G cells and D cells per area unit and the G cell/D cell ratio was studied in control subjects and patients with duodenal or gastric ulcer. A great inter-individual variation in the population density of both types of cells was observed in the three groups studied. G cell density was significantly decreased in both duodenal and gastric ulcer patients, when compared with controls; whereas no difference in G cell density was seen between duodenal ulcer patients and gastric ulcer patients. However, D cell density was significantly decreased in duodenal ulcer patients when compared with control subjects and gastric ulcer patients. In this latter group, D cell density was also lower than in control subjects. A significant positive linear correlation between G cell number and D cell number was found in the three groups studied. The G cell/D cell ratio was significantly increased in duodenal and gastric ulcer patients when compared with controls. This was mainly due to a decrease in D cell numbers. It is concluded that a local deficit in antral D cells in patients with peptic ulcer may favor the pathogenesis of ulcer disease.

Adult↗
PubMed1976

Charcot arthropathy secondary to amyloid neuropathy.

Neuropathic (Charcot) ankle joints developed in a 50-year-old patient with end-stage renal disease from primary, nonfamilial amyloidosis. Sensory neuropathy in the legs had been noted three years before the onset of uremia and had porgressed. Sural nerve, but not synovial biopsy specimen, showed amyloid in and around arteriolar walls by light and electron microscopy. Since Charcot joints are only rarely associated with amyloid neuropathy, it is possible that uremic neuritis, or prolonged survival by dialysis, contributed to progression of the neuropathy, allowing subsequent joint degeneration.

Amyloidosis↗
PubMed1976

[Pharmacological reactivity in cricetus aureus uterus (author's transl)].

The motility of the isolated Cricetus auratus uterus was studied and compared to that of other species. Oxitocyn, epinephrine, norepinephrine, histamine, 5-hydroxy-tryptamine and acetylcholine were used as spasmogen agents. There was not contractil response with epinephrine or nor-epinephrine. Histamine reduced basal tonus. There was contraction with acetylcholine, oxytocin and 5-hydroxy-tryptamine. Cricetus auratus uterus appeared more sensitive when the contraction was registered by the isometric method. No taquifilaxy was produced by 5-hydroxy-tryptamine, as opposed to such effect in rat uterus. The Cricetus auratus uterus has, therefore, shown similar reactivity to that of rat, but different from rabbit and guinea-pig.

Acetylcholine↗
PubMedDate not supplied

Acetaminophen-induced fulminant hepatic failure in dogs.

Results concerning morphological and biochemical changes following intravenous administration of different doses of acetaminophen in dogs are reported. Acetaminophen infusion, as a parenteral solution (500 mg per kg per 90 min), produced fulminant hepatitis characterized by a good correlation between Portmann's grade of lesion and percentage of necrosis. All animals died within 76 hr after intoxication. Analysis of biochemical parameters revealed positive correlation between serum bilirubin levels and severity of the hepatic lesion. The experimental model of acetaminophen-induced hepatotoxicity is proposed as a model for evaluation of the therapeutic efficacy of new medical and surgical procedures.

Acetaminophen↗
PubMedDate not supplied

Value of serum neuron-specific enolase in nonsmall cell lung cancer.

To assess the prognostic value of pretreatment serum neuron-specific enolase (NSE) in nonsmall cell lung cancer (NSCLC), levels were measured in 84 NSCLC patients, 40 healthy controls, and 20 patients with benign pulmonary diseases. NSE concentration was higher in NSCLC (11.7 +/- 10.8 ng/ml) (mean +/- SD; median = 9.7 ng/ml) than in the two control groups (p < 0.001). Serum NSE was neither related with the tumor-node-metastasis (TNM) stage, nor with histologic subtype. At a cutoff value of 15 ng/ml, NSE had a sensitivity of 27.3% and a specificity of 96%. Patients with a preoperative NSE level < 15 ng/ml showed significantly longer 24-month survival than those whose initial levels were > 15 ng/ml (70 vs, 47%; p < 0.05), and this was confirmed after stratifying by TNM stage. Likelihood of tumor relapse in I, II, and IIIa TNM stages showed similar behavior. These findings suggest that NSE could be used as an adjunctive prognostic test in NSCLC patients.

Aged↗
PubMedDate not supplied

Cytologic diagnosis of leishmaniasis in HIV infection. A report of eight cases.

BACKGROUND: Leishmania organisms are among the intracellular microorganisms with a tendency to develop in patients with the acquired immunodeficiency syndrome (AIDS). With increasing travel to endemic areas by patients with human immunodeficiency virus (HIV) infection, it is becoming a more-frequent diagnosis in nonendemic areas. CASES: Ten cytologic specimens from eight patients with leishmaniasis and AIDS were reviewed. Eight samples were obtained from lymph nodes through fine needle aspiration (FNA). Another sample was obtained after scraping a tongue ulcer. The last one was an ascitic fluid specimen. Smears showed numerous parasitized histiocytes with abundant intracellular Leishmania organisms (amastigotes). Extracellular microorganisms were also abundant. Diff-Quik-stained smears allowed the clear recognition of the characteristic morphologic appearance with a deep-staining area (nuclei) and paranuclear zone (kinetoplast). Intracellular organisms were round, while single, extracellular forms were a more elongated. CONCLUSION: The polymorphous clinical manifestations usually seen in patients suffering from leishmaniasis and AIDS constitute a diagnostic challenge that can be facilitated by cytopathologic examination. Cytology permits easy and rapid identification of Leishmania amastigotes, allowing a specific diagnosis and treatment.

Adult↗
PubMedDate not supplied

Fine needle aspiration cytology of breast fibroadenoma. A cytohistologic correlation study of 405 cases.

OBJECTIVE: To evaluate the cytohistologic correlation of breast fibroadenoma (FA) in order to assess the value of cytology in the conservative management of this lesion. STUDY DESIGN: A retrospective analysis of all aspirates diagnosed as FA or fibroadenomatous lesion (n = 1,549) for which a histologic follow-up study was available (n = 362). Forty-three aspirates, including 14 nonrepresentative smears, from histologically proven FAs with a different cytologic report were also included in the study. RESULTS: Cytohistologic agreement was present in 287 of the 362 cytodiagnoses. Lack of correlation was observed in 75 cases. Most diagnostic errors accumulated in the older patient group. The sensitivity of the cytologic diagnosis of FA was 86.9% (90.8% excluding nonrepresentative cases), with a positive predictive value of 79.3%. In 43 cases a histologic diagnosis of FA was given after previous erroneous (n = 29) or nonrepresentative cytodiagnoses (n = 14). The specificity of the cytologic diagnosis of FA reached 93.8%, with a negative predictive value of 96.3% (97.5% excluding nonrepresentative cases). Regarding malignancy, five tumors were diagnosed as FA and were malignant. No false positive diagnoses of malignancy were given, but nine aspirates were included in the category "suspicious for carcinoma." CONCLUSION: FA of the breast remains a diagnostic challenge for the cytopathologist. A considerable amount of benign breast lesions can mimic FA on cytology, and such diagnostic categories as "fibroadenomatous lesion" or "consistent with FA" are associated with low diagnostic accuracy. While the cytologic requisites for entering a program of conservative management of FA are established, it seems that strict diagnostic criteria should be applied even at the expense of diminishing sensitivity.

Adult↗
PubMedDate not supplied

Nodular pseudoangiomatous stromal hyperplasia of the breast. Cytologic features.

OBJECTIVE: To define and discuss the cytologic findings in six cases of nodular pseudoangiomatous stromal hyperplasia (PASH) of the breast. STUDY DESIGN: Retrospective evaluation of the medical records, cytologic and histologic material from six patients with palpable mammary PASH. Cases in which PASH was associated with other predominant mammary lesions were not included in the study. RESULTS: A total of six patients with histologically proven PASH underwent aspiration in nine occasions (three patients studied twice). Clinically, five patients were diagnosed as having fibroadenoma or another benign lesion, and in one patient carcinoma was suspected. In two patients, mammography disclosed rapid growth of the lesion. Seven aspirations, performed on five patients, were diagnosed as fibroadenoma (n = 5) or fibroadenomatous lesion (n = 2). An eighth aspiration was cystic and reported as fibrocystic disease. The last case was erroneously diagnosed as suspicious for carcinoma. Even after revision, the cytologic similarities of PASH with fibroadenoma were remarkable. Most smears were less cellular than those of conventional fibroadenomas. Epithelial clusters showed variable size, with a predominance of medium to small groups. Stromal elements were minimal or absent. Background cellularity was composed of round to oval naked nuclei and others with spindle shapes. Occasional epithelial clusters showed cellular dissociation and slight atypia. CONCLUSION: Due to the absence of specific cytologic features and similarities to fibroadenoma, a precise diagnosis of PASH cannot be made on cytologic material. However, the majority of cases can be diagnosed correctly as benign, allowing appropiate treatment.

Adult↗
PubMedDate not supplied

[Cigarette smoking and its relation to pregnancy and lactation in Arica (Chile)].

Cigarette smoker and non smoker mothers from Africa, Chile, were followed along pregnancy and lactation and the influence of cigarette smoking on infant's birth weight and length of lactation was assessed from a sample of 240 pregnant women, 87 (36.3%) of them were actively smoking mothers and 33 among these (37.9%) smoked throughout all pregnancy and lactation. Mothers who smoked along lactation showed significantly shorter exclusive breast feeding time (2.6 month) in comparison with non smokers (3.5 month, p < 0.05) and their total lactation time was also reduced (4.2 vs. 5.3 months respectively, p < 0.01).

Adult↗