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J M Ramos

Publications and source records attributed to J M Ramos.

At least 37 records · Page 2Linked to original sources
PubMed1999

[Isolated left anterior artery disease: angiographic features and clinical evolution of patients submitted to surgical myocardial revascularization or angioplasty].

The option for revascularization and the choice of intervention in isolated left anterior descending artery disease may be controversial. We decided to study retrospectively a group of revascularized patients (PTCA or surgery), with previous isolated LAD disease, to evaluate the angiographic features of LAD lesion, its contribution to the persistence of symptoms after revascularization and also to compare the occurrence of cardiac events in the two subgroups (PTCA and surgery). We studied 87 patients (mean age 57 +/- 10 years) submitted to myocardial revascularization (68 PTCA; 19 surgery), whose clinical evolution was followed for a mean period of 49 +/- 10 months (cardiac events: death, myocardial infarction, angina, heart failure, PTCA, surgery). We evaluated in cineangiography angiographic features of LAD lesions (degree of stenosis, lesion length and diameter, ectasia, luminal irregularity, ulcerated plaque, eccentricity, thrombus, calcification, type of lesion). On comparing angiographic features, we noted coronary lesions were longer in operated patients (p < 0.05) and a tendency for more complex lesions in this group (p = 0.08). After revascularization, 65% of PTCA patients and 26% of operated patients maintained angina (p < 0.01). The frequency of events was significantly higher in patients submitted to PTCA (84%) due to the greater occurrence of angina (65%). Sixteen percent PTCA were redilated and 6% operated whereas 11% of the surgical group were reoperated, without statistical difference regarding reintervention between the two groups. In the PTCA group, the greater frequency of angina and the necessity of a new PTCA could reflect restenosis. The disappearance of angina in operated patients may reflect probable patency of coronary bypass.

Aged↗
PubMed1998

Retrograde amnesia for spatial information: a dissociation between intra and extramaze cues following hippocampus lesions in rats.

Several recent studies have shown a flat retrograde amnesia for spatial information following lesions to the hippocampus in rats and mice. However, the results of the present investigation demonstrate that in rats that presurgically learned a spatial reference memory task based on extramaze cues, a temporally graded retrograde amnesia is evident following lesions to the hippocampus (1, 16, 32 or 64 days after learning) if two conditions are met. First, that a wide range of retention intervals is used, and second, that independent groups of rats are tested, not a single group that learns different spatial discrimination tasks at different times (expt 1). The results of expt 2 show that the hippocampus does not serve as a consolidating mechanism when the spatial task learned presurgically is based on intramaze cues. Taken together, these results indicate that the hippocampus is critical for the storage and/or retrieval of spatial reference information that was learned up to 1 month before hippocampus damage; however, in the absence of the hippocampus, efficient retention can still occur provided that the spatial knowledge was learned in a simple associative manner.

Amnesia, Retrograde↗
PubMed1998

[Methods for evaluating diagnostic tests in Enfermedades Infecciosas y Microbiología Clínica].

BACKGROUND: In the field of infectious diseases and clinical microbiology, the evaluation of diagnostic tests (DT) is an important research area. The specific difficulties of this type of research has motivated that have not caught the severity methodological of others areas of clinical research. This article try to asses and characterize the methodology of articles about DT published in Enfermedades Infecciosas y Microbiología Clínica (EIMC) journal. METHODS: Forty-five articles was selected in the EIMC journal during the 1990-1996 period, because of determinate the sensitivity and specificity of different DT. Methodological standards, extensively accepted was used. RESULTS: In all of articles, except one (98%) the gold standard was specified yours use, however in 4 studies (9%) include the DT in the gold standard (incorporation bias). The correct description of DT was reported in 75% of cases, but only in 11% cases the reproducibility of test was evaluated. The description of source of reference population, standard of inclusion and spectrum of composition was described in 58, 33 and 40% of articles, respectively. In 33% of studies presented workup bias, only 6% commented blind-analysis of results, and 11% presented indeterminate test results. Half of the studies reported test indexes for clinical subgroups, only one article (2%) provided numerical precision for test indexes, and only 7% reported receiver operating characteristics curves. CONCLUSIONS: The methodological quality of DT research in the EIMC journal may improve in different aspects of design and presentation of results.

Diagnostic Techniques and Procedures↗
PubMed1997

Increasing urinary cotinine concentrations at elevated temperatures: the role of conjugated metabolites.

The presence of cotinine, a nicotine metabolite, in urine above a specified cutoff concentration is commonly used to distinguish smokers from nonsmokers, as in smoking cessation studies. A stability study of cotinine in urine was carried out after questions arose concerning analyte stability at elevated storage and shipment temperatures. Aliquots from a smokers urine pool were stored at 5, 25, 40, 50 and 60 degrees C for 30 days. Another set of aliquots, obtained by diluting the smokers pool 1:1 with nonsmokers urine, were stored under the same conditions. Free cotinine levels, determined by a stability-indicating gas chromatographic/mass spectrometric (GC/MS) assay, increased over the 30-day period at higher storage temperatures. Cotinine concentrations in the aliquots stored at 60 degrees C, for example, nearly doubled over 30 days (1301 to 2476 ng/ml), with similar proportional increases observed in the aliquots diluted with nonsmokers urine. Since cotinine can be excreted to a large degree as cotinine-N-glucuronide, this conjugated metabolite was determined by an indirect method. As the storage temperature increased, the free/conjugated cotinine ratio dramatically increased, pointing to cotinine-N-glucuronide as the source of the additional free cotinine at the higher storage temperatures. The results of this study are of much practical importance, since urine samples with free cotinine concentrations just below a cutoff value may become positive for smoking status if suitably low temperatures cannot be maintained during sample handling and shipment.

Chromatography, Gas↗
PubMed1997

Focal infections due to non-typhi Salmonella in patients with AIDS: report of 10 cases and review.

Bacteremia due to non-typhi Salmonella is frequent in human immunodeficiency virus (HIV)-infected patients; however, focal complications rarely have been reported. Ten of 38 HIV-infected patients (26.3%) with salmonellosis documented over a period of 9 years had focal suppurative complications; only 19 (3.9%) of 490 adults without HIV infection who were seen during the same period had focal complications (P = .001). Infections of the urinary tract, lungs, and soft tissue, followed by arthritis, endocarditis, and meningitis were most frequently seen. Although salmonellosis occasionally heralded HIV infection, most patients were severely immunocompromised and had CD4 cell counts of <100/mm3. The mortality rate was 50%, equivalent to that observed among patients with other immunosuppressive disorders (52.6%). Major emphasis must be put on intensive therapy for salmonella bacteremia and prevention of its complications.

AIDS-Related Opportunistic Infections↗
PubMed1997

[A review of infectious endocarditis due to Candida].

OBJECTIVE: As fungal endocarditis is a serious disease, frequently requiring cardiac surgery, a review was made of the experience of our Departments in this pathology. DESIGN: A retrospective analysis of clinical, echocardiographic and surgical data. SETTING: Patients studied in a tertiary care Hospital with cardiac surgery available. PATIENTS: Between 1984 and 1994 there were ten cases of candida endocarditis in nine patients, four male and five female, mean age--45 +/- 12 years (31-65). INTERVENTIONS: The following parameters were analysed: clinical (predisposing factors, clinical evolution, complications, therapy and mortality), echocardiographic (presence of vegetations, abscesses, valvular regurgitations). Patients studied in other Centres and referred to our Department only for examination (echocardiograms) were excluded from this analysis. RESULTS: Eight cases in seven patients were prosthetic valve endocarditis and two native valve endocarditis. No patient was drug addicted. Seven cases of prosthetic valve endocarditis developed less than one year after surgery and another had a gynecological fungal infection as the cause of the endocarditis. Four patients had had previous endocarditis. There were four embolic events and three developed heart failure. There were three perivalvular infections, six valvular regurgitations and only one case with huge vegetations on echocardiography. Nine patients were treated with amphotericin B, in five fluocytosin was added and in four ketoconazol, which was replaced by flukonazol in one patient. Therapy was continued for at least eight weeks. Six patients were operated during the acute stage and one died. One patient was operated on late after the infection. Three patients died during the active stage. In a follow up of 5.2 +/- 4.8 years (8 months to 8 years) there was one fatal candida endocarditis relapse, one fatal candida sepsis, one non cardiac death, one patient developed a periprosthetic leak and one had recurrent systemic embolization. Abscesses/pseudoaneurysms were found in five out of seven patients submitted to surgery. CONCLUSION: Candida infective endocarditis has a bad prognosis, specially in those patients not operated early; it develops in patients with predisposing factors, which in our series were a previous infective endocarditis (four patients) and/or a prosthetic valve implantation less than one year before; it has important morbidity with multiple embolic events, perivalvular involvement, valvular regurgitation and heart failure.

Adult↗
PubMed1996

Changes in susceptibility of Salmonella enteritidis, Salmonella typhimurium, and Salmonella virchow to six antimicrobial agents in a Spanish hospital, 1980-1994.

To determine changes in the susceptibility patterns of Salmonella enteritidis, Salmonella typhimurium, and Salmonella virchow over time, resistance to ampicillin, chloramphenicol, tetracycline, gentamicin, trimethoprim/sulfamethoxazole, and nalidixic acid was studied by the disk diffusion method in 1,024, 191, and 61 clinical isolates of these organisms, respectively. All isolates were recovered from 1980 to 1994 at a hospital in Madrid, Spain. Salmonella enteritidis isolates were less resistant (10.9%) than Salmonella typhimurium (43.5%) and Salmonella virchow (36.1%; p < 0.001). The incidence of resistance of Salmonella enteritidis to ampicillin increased from 2.7% during the period 1980-1982 to 15.6% during 1992-1994 (p < 0.001). The resistance of Salmonella typhimurium to ampicillin, chloramphenicol, and tetracycline increased from 15.2%, 7.6%, and 21.2% respectively in 1980-1982 to 73.3%, 46.7%, and 73.3% in 1992-1994 (p < 0.001). These marked increases in antimicrobial resistance suggest the need for public health interventions, several of which are discussed.

Anti-Bacterial Agents↗
PubMed1996

Clinical spectrum of urinary tract infections due on nontyphoidal Salmonella species.

We performed a retrospective analysis of 28 cases of bacteriuria due to nontyphoidal Salmonella (NTS). Twenty-one patients (75%) had symptoms of urinary tract infection (16, cystitis; 3, pyelonephritis; and 2, renal abscess), and 7 remained asymptomatic. In 24 cases NTS was the sole pathogen isolated from urine. Salmonella enteritidis (a Salmonella subgroup 1 serotype) was the serotype most frequently isolated (16 cases), followed by Salmonella enteritidis serotype typhimurium (5 cases). Sixteen patients (57%) were severely immunocompromised, and 14 (52%) had urologic abnormalities. Recurrence of bacteriuria occurred in four patients. It is suggested that in cases of urinary salmonellosis one must consider the existence of an occult urologic problem or severe immunosuppression.

Abscess↗
PubMed1996

Classifying extraintestinal non-typhoid Salmonella infections.

Non-typhoid Salmonella infection in man has been divided into five clinical groups: gastroenteritis, enteric fever, bacteraemia, chronic carrier state and localized infection. This classification has neither pathogenic nor prognostic significance. We retrospectively reviewed the charts of 183 patients with extraintestinal salmonellosis who presented to our institution during a period of 32 years. Patients were classified into four groups: primary bacteraemia (PB), enteritis-associated bacteraemia (secondary bacteraemia) (SB), digestive focal infection (DI) and non-digestive focal infection (NDI). Sex, age, acquisition, underlying disease and outcome were compared between patients with bacteraemia and diseases with focal infection. The differences found between PB and SB were: community acquisition (66% in PB and 85% in SB, p = 0.06) severe immunosuppression (53% in PB and 15% in SB, p < 0.001) and mortality (37% in PB and 3% in SB, p < 0.001). The differences found between NDI and DI were: age over 60 years (45% in NDI and 18% in DI, p < 0.05), severe immunosuppression (51% in NDI and 12% DI, p < 0.001) and associated bacteraemia (38% in NDI and 6% in DI, p < 0.001). This classification of extraintestinal salmonellosis may have pathogenic and prognostic implications, and could help us to understand the clinical significance of this disease.

Aged↗