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Biomedical subjects

J Carballido

Publications and source records attributed to J Carballido.

47 records · Page 3Linked to original sources
PubMed1989

The immunomodulatory effects of interferon-gamma on mature B-lymphocyte responses.

Interferon-gamma (IFN-gamma) exerts a broad spectrum of activities which affect the responses of mature B-cells. It strongly inhibits B-cell activation, acts as a B-cell growth factor (BCGF), and also induces final differentiation to immunoglobulin (Ig) production. IFN-gamma is deeply involved in the differential control of isotype expression, as it enhances IgG2a production and suppresses both IgG1 and IgE production. Although it is now possible to draw a general scheme of the effects of IFN-gamma on B-cells, a number of paradoxical results still exist in the field. In this manuscript, different experimental systems are analyzed in an attempt to explain these apparent paradoxes.

Animals↗
PubMed1987

Inhibition of human natural killer (NK) activity by calcium channel modulators and a calmodulin antagonist.

The presence of calcium (Ca2+) in the culture medium is a requirement for the NK cytotoxic reaction. To further explore the role of Ca2+ and calmodulin (a cytoplasmic protein that mediates most of the biological effects of Ca2+) in this process, we evaluated the effects of nifedipine (a Ca2+ channel antagonist), BAY-K-8644 (a Ca2+ channel agonist), and haloperidol (an inhibitor of calmodulin) on the NK activity of human peripheral blood mononuclear cells (PBMC), and the augmentation of this activity by recombinant interleukin 2 (r-IL 2) and interferon-gamma (r-gamma-IFN). We found that all of these drugs inhibit NK activity in a dose-dependent fashion. This appears to result from interference with the programming for lysis stage of the lytic process. In contrast, the presence of these agents during the incubation of PBMC with r-IL 2 or r-gamma-IFN did not induce any change in the enhancement of NK activity. These data suggest that Ca2+ exerts its effect at the intracellular level during the NK cytotoxic process, and that the augmentation of NK activity by lymphokines is independent of the calcium-calmodulin system.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMedDate not supplied

Diminished T lymphocyte proliferative response to polyclonal mitogens in acute brucellosis patients.

T lymphocytes from 21 untreated patients with acute brucellosis were tested for their proliferative response to polyclonal mitogens. The purified T lymphocytes from these patients showed a defective proliferative response to plant lectins and anti CD3 monoclonal antibodies with respect to the response observed in T lymphocytes from 21 healthy controls (p < 0.05). This defective proliferative response was not corrected by the exogenous addition of interleukin-2 or tumor necrosis factors alpha or beta to the culture medium. After antibiotic therapy, the proliferative response to the mitogens in T lymphocytes was found to be similar to that of the healthy controls (p > 0.05), and significantly higher than that found before treatment (p < 0.05). It was concluded that T lymphocytes from acute brucellosis patients have a defective proliferative response to membrane mitogenic signals, which disappears when the patients are cured after antibiotic treatment.

Acute Disease↗
PubMedDate not supplied

Left ventricular volume reduction and reconstruction in ischemic cardiomyopathy.

BACKGROUND: Ischemic cardiomyopathy can be the result of large or small myocardial infarctions or due to myocardial hibernation. Patients with an end-systolic volume index >100 mL¿m2 do not benefit from revascularization alone and require an operation that reduces ventricular volume. Various approaches to reduce ventricular volume have been described. We applied several of these techniques in patients with end-stage ischemic cardiomyopathy. METHODS: Forty eight patients with end-stage ischemic cardiomyopathy (Class III-IV) underwent left ventricular volume reduction operations with coronary revascularization and mitral valve repair or Alfieri valvoplasty. Fourteen patients underwent interpapillary resections, 22 anterior resections, 4 posterior resections, 2 anterior and posterior resections, and 6 patients reduction of left ventricular volume with endocavitary patches. RESULTS: All the techniques used improved left ventricular function. Analysis of mortality revealed that extensive resections (interpapillary, anterior, and posterior resection) had a 43% mortality. However, a limited resection or a ventricular reconstruction with an endocavitary patch had only a 12.5% mortality. When we changed our approach to a more conservative one, mortality was reduced from 26% the first 12 months to 13% in the last 15 months of the study. CONCLUSIONS: Ischemic cardiomyopathy has a poor prognosis if the end-systolic volume index exceeds 100 mL/m2. Various procedures exist to reduce left ventricular volume. Extensive ventricular resections improve ventricular function, but have a high mortality. This led us to use other methods of ventricular volume reduction such as more conservative resections combined with left ventricular reconstructions or ventricular volume reduction with endocavitary patches. Mortality was reduced significantly by this approach. The patients that survived have remained Class I-II in a follow-up that extends up to 30 months. Surgical therapy of Class III-IV ischemic cardiomyopathy is feasible, but aggressive ventricular resections have a high mortality. We advocate a more reconstructive approach with limited or no ventricular resection.

Aged↗
PubMedDate not supplied

[Bladder carcinosarcoma with osteosarcomatous differentiation].

Osteoid tissue can eventually be identified outside the bone skeleton adopting the form of metastasis, osteoid metaplasia or primitive osteosarcoma. This latter presentation is most frequently located in soft tissues and exceptionally at the visceral level. The term used for any of these forms is extra-bone osteogenic sarcoma. This paper reports the case of a 62 year-old female patient diagnosed with vesical urothelial carcinosarcoma treated with external radiotherapy. After a disease-free period of 20 years the patient developed osteosarcomatous-differentiated vesical carcinosarcoma. A literature review is made to analyze, from a clinical and histopathological perspective, several items of interest presented by this pathology. The role of sarcomatous radio-induction is also highlighted. Finally, we emphasize the relevance of using radical treatments from the start, so as to restrain the highly malignant potential of this condition.

Carcinosarcoma↗
PubMedDate not supplied

[Pneumoperitoneum: infrequent complication of lithiasic pyonephrosis].

A case of lithiasic pyonephrosis evolving with intrapyelic gas formation, with positive urinary culture for Escherichia coli, is presented. Original clinical presentation was a picture of acute peritonitis with pneumoperitoneum. Clinical and radiological findings were indicative of exploratory laparotomy. The picture was resolved surgically, the procedure adopted being nephrectomy with retroperitoneal space drainage and empirically chosen antibiotics. The paper establishes the uncommon nature of this complication, and includes a literature review.

Aged↗
PubMedDate not supplied

[Experience with the use of an implantable automatic cardioverter defibrillator].

An automatic implantable cardioverter-defibrillator with pacemaker was implanted in Cuba, in ten patients with malignant ventricular arrhythmias, sudden cardiac collapse, and ventricular tachycardia with syncope, after a previous electrophysiological study for analysis of the arrhythmia and pharmacological evaluation. The patients were 9 males, ranging in age from 23 a 70 years, with a mean of 48 years, and an ejection fraction of 32% (18-62%). The etiologies were: an old myocardial infarction (7 cases) and dilated cardiomyopathy (3 cases). During the follow-up, mean from 2 to 25 months, four patients received effective shocks for rapid palpitations and presyncope. Two patients died, one due to incessant ventricular tachycardia and one of a cause unrelated to device. We concluded that the GUARDIAN 4201 and 4202 device are useful to prevent sudden cardiac death in high risk patients who experienced a life threatening arrhythmia.

Adult↗
PubMedDate not supplied

[Renal hydatid cyst: a nuclear magnetic resonance study].

A case of renal hydatid cyst (R.H.C.) in which study both traditional diagnostic methods (such as serology, radiology, ecoraphia, C.A.T., etc.) and the newer ones, including Nuclear Magnetic Resonance (N.M.R.) were used, is presented. The diagnostic characteristics of this type of cystic pathology were reviewed through N.M.R. study, as well as current criteria to outline a correct differential diagnosis with simple Renal Cysts (R.C.). Finally, a theoretical place for each of these methods within the diagnostic algorithm of renal masses is suggested.

Aged↗
PubMedDate not supplied

[Chemoprophylaxis of superficial tumors of the bladder with thiotepa: long-term results].

A retrospective study was done on the long-term evolution of 48 patients diagnosed of transitional cell carcinoma of the bladder who were treated with full transurethral resection and intracavitary chemoprophylaxis with Thiotepa. All patients presented a minimum disease control period of 36 months, and were followed for 85.3 months on the average (38-156) months. The actuarial study of the relapse-free intervals turned out into a possibility of 89.3% of patients without a relapse by 5 years, and of 64.6% by 10 years. The actuarial study of tumor progress showed that 91.4% and 58.8% of the patients were free of progression by 5 and 10 years respectively. pT1-G3 tumors did not show greater relapse rate nor progression than the rest of cases, it is therefore convenient to consider other prognostic factors in the long-term evolution of these patients. 85.7% of patient deaths were due to direct consequence of the bladder tumor. These results and their clinical implications are analyzed.

Administration, Intravesical↗