Biomedical subjects

José M Peña

Publications and source records attributed to José M Peña.

6 recordsLinked to original sources

PubMed2006

[Reappraisal of the standard method (Light's criteria) for identifying pleural exudates].

BACKGROUND AND OBJECTIVES: Light's criteria remain the best method for separating pleural exudates from transudates. We assessed their operating characteristics, as well as those resulting from omitting the pleural fluid to serum lactate dehydrogenase (LDH) ratio from the original criteria (abbreviated Light criteria), in a large series of patients. We also searched for the best combination of pleural fluid parameters, including protein, LDH and cholesterol that identify exudates. PATIENTS AND METHOD: We conducted a retrospective study of 1,490 consecutive patients with pleural effusion who underwent a diagnostic thoracentesis. There were 1,192 exudates and 298 transudates. Sensitivity, specificity, area under ROC curve, and odds ratio for both individual and combined pleural fluid parameters were calculated. RESULTS: Light's criteria yielded 97.5% sensitivity and 80% specificity. Both abbreviated Light criteria (sensitivity: 95.4%; specificity: 83.3%) and the combined use in an "or" rule of pleural fluid protein and LDH (sensitivity: 95.4%; specificity: 80,2%) had similar discriminative properties than standard criteria. CONCLUSIONS: Diagnostic separation of pleural effusions into exudates or transudates can be done effectively thorough the abbreviated Light criteria when the serum LDH value is not available. On the other hand, if venipuncture wants to be avoided (an unusual circumstance) the combination of pleural fluid protein and LDH represents an alternative to Light's criteria.

Cholesterol↗

PubMed2005

Lopinavir/ritonavir as single-drug therapy for maintenance of HIV-1 viral suppression: 48-week results of a randomized, controlled, open-label, proof-of-concept pilot clinical trial (OK Study).

OBJECTIVE: This study evaluated maintenance with lopinavir/ritonavir monotherapy vs. continuing lopinavir/ritonavir and 2 nucleosides in HIV-infected patients with suppressed HIV replication. DESIGN: Randomized, controlled, open-label, multicenter, pilot clinical trial. METHODS: Adult patients were eligible if they had no history of virologic failure while receiving a protease inhibitor, were receiving 2 nucleosides + lopinavir/ritonavir (400/100 mg b.i.d.) for >1 month and had maintained serum HIV RNA <50 copies/mL for >6 months prior to enrollment. RESULTS: Forty-two patients were randomly assigned 1:1 to continue or stop the nucleosides. At baseline there were no significant differences between groups in median CD4 cells/muL (baseline or nadir), pre-HAART (highly active antiretroviral therapy) HIV log10 viremia, or time with HIV RNA <50 copies/mL prior to enrollment. After 48 weeks of follow-up, percentage of patients remaining at <50 HIV RNA copies/mL (intention to treat, M = F) was 81% for the monotherapy group (95% CI: 64% to 98%) vs. 95% for the triple-therapy group (95% CI: 86% to 100%); P = 0.34. Patients in whom monotherapy failed had significantly worse adherence than patients who remained virally suppressed on monotherapy. Monotherapy failures did not show primary resistance mutations in the protease gene and were successfully reinduced with prerandomization nucleosides. Mean change in CD4 cells/microL: +70 (monotherapy) and +8 (triple) (P = 0.27). Mean serum fasting lipids remained stable in both groups. No serious adverse events were observed. CONCLUSION: Most of the patients maintained with lopinavir/ritonavir monotherapy remain with undetectable viral load after 48 weeks. Failures of lopinavir/ritonavir monotherapy were not associated with the development of primary resistance mutations in the protease gene and could be successfully reinduced adding back prior nucleosides.

Adult↗

PubMed2004

Bayesian network multi-classifiers for protein secondary structure prediction.

Successful secondary structure predictions provide a starting point for direct tertiary structure modelling, and also can significantly improve sequence analysis and sequence-structure threading for aiding in structure and function determination. Hence the improvement of predictive accuracy of the secondary structure prediction becomes essential for future development of the whole field of protein research. In this work we present several multi-classifiers that combine the predictions of the best current classifiers available on Internet. Our results prove that combining the predictions of a set of classifiers by creating composite classifiers is a fruitful one. We have created multi-classifiers that are more accurate than any of the component classifiers. The multi-classifiers are based on Bayesian networks. They are validated with 9 different datasets. Their predictive accuracy results outperform the best secondary structure predictors by 1.21% on average. Our main contributions are: (i) we improved the best know predictive accuracy by 1.21%, (ii) our best results have been obtained with a new semi naïve Bayes approach named Pazzani-EDA and (iii) our multi-classifiers combine results of previously build classifiers predictions obtained through Internet, thanks to our development of a Java application.

Bayes Theorem↗

PubMed2003

Searching for universals: preliminary evidence for the validity of substance abuse subtypes in a sample of Mexican American youths.

Recent studies of substance abuse typologies indicate that multivariate models originally developed for identifying subtypes of alcoholics are valid among users of other substances, including heroin, cocaine, and marijuana. Little is known regarding the generalizability of these subtypes across culturally different subgroups. If substance abuse typologies are universal, then controlling for subtype may prove to be an effective research strategy in studies attempting to distinguish the separate and specific contribution of culturally related factors to risk for substance use and to treatment response. In this article, we present data that replicate the Type A-Type B distinction, developed by Babor et al., in a sample of Hispanic youths with substance involved problems.

Adolescent↗

PubMed2003

Prognosis and clinical evaluation of infection caused by Rhodococcus equi in HIV-infected patients: a multicenter study of 67 cases.

OBJECTIVE: To assess the clinical characteristics and the factors that influenced the prognosis of patients with HIV and infection caused by Rhodococcus equi. DESIGN: Observational, multicenter study in 29 Spanish general hospitals. SETTING: These hospitals comprised a total of 20,250 beds for acute patients and served a population of 9,716,880 inhabitants. PATIENTS: All patients with HIV and diagnosed R equi infection until September 1998. RESULTS: During the study period, 19,374 cases of AIDS were diagnosed. Sixty-seven patients were included (55 male patients; mean +/- SD age, 31.7 +/- 5.8 years). At the time of diagnosis of R equi infection, the mean CD4+ lymphocyte count was 35/ micro L (range, 1 to 183/ micro L) and the stage of HIV infection was A3 in 10.4% of patients, B3 in 31.3%, C3 in 56.7%, and unknown in 1.5%. R equi was most commonly isolated in sputum (52.2%), blood cultures (50.7%), and samples from bronchoscopy (31.3%). Chest radiographic findings were abnormal in 65 patients (97%). Infiltrates were observed in all of them, with cavitations in 45 patients. The most active antibiotics against the strains isolated were vancomycin, amikacin, rifampicin, imipenem, ciprofloxacin, and erythromycin. After a mean follow-up of 10.7 +/- 12.8 months, 23 patients (34.3%) died due to causes related to R equi infection and 6 other patients showed evidence of progression of the infection. The absence of highly active antiretroviral therapy (HAART) was independently associated with mortality related to R equi infection (relative risk, 53.4; 95% confidence interval, 1.7 to 1,699). Survival of patients treated with HAART was much higher than that of patients who did not receive this therapy. CONCLUSIONS: Infection by R equi is an infrequent, opportunistic complication of HIV infection and occurs during advanced stages of immunodepression. In these patients, it leads to a severe illness that usually causes a bacteremic, cavitary pneumonia, although HAART can improve the prognosis.

Actinomycetales Infections↗

PubMed2003

The influence of French, Spanish, and English legal traditions on early mental health proceedings in Louisiana.

Unlike other jurisdictions in the United States where the basis of the law can be traced more exclusively to the common law of England, the legal system in Louisiana also has origins in the laws of France and Spain. In this article, the authors describe the laws and procedures that developed early in Louisiana's history for the involuntary care and civil commitment of the mentally ill, focusing on the laws that were passed after the American takeover in 1803.

Civil Rights↗