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Background: Little evidence exists of the burden and predictors of cardiac death after transcatheter aortic valve replacement (TAVR)., Objectives: The purpose of this study was to assess the incidence and predictors of cardiac death from advanced heart failure (HF) and sudden cardiac death (SCD) in a large patient cohort undergoing TAVR., Methods: The study included a total of 3,726 patients who underwent TAVR using balloon (57%) or self-expandable (43%) valves. Causes of death were defined according to the Valve Academic Research Consortium-2., Results: At a mean follow-up of 22 ± 18 months, 155 patients had died due to advanced HF (15.2% of total deaths, 46.1% of deaths from cardiac causes) and 57 had died due to SCD (5.6% of deaths, 16.9% of cardiac deaths). Baseline comorbidities (chronic obstructive pulmonary disease, atrial fibrillation, left ventricular ejection fraction ≤40%, lower mean transaortic gradient, pulmonary artery systolic pressure >60 mm Hg; p < 0.05 for all) and 2 procedural factors (transapical approach, hazard ratio [HR]: 2.38, 95% confidence interval [CI]: 1.60 to 3.54; p < 0.001; presence of moderate or severe aortic regurgitation after TAVR, HR: 2.79, 95% CI: 1.82 to 4.27; p < 0.001) independently predicted death from advanced HF. Left ventricular ejection fraction ≤40% (HR: 1.93, 95% CI: 1.05 to 3.55; p = 0.033) and new-onset persistent left bundle-branch block following TAVR (HR: 2.26, 95% CI: 1.23 to 4.14; p = 0.009) were independently associated with an increased risk of SCD. Patients with new-onset persistent left bundle-branch block and a QRS duration >160 ms had a greater SCD risk (HR: 4.78, 95% CI: 1.56 to 14.63; p = 0.006)., Conclusions: Advanced HF and SCD accounted for two-thirds of cardiac deaths in patients after TAVR. Potentially modifiable or treatable factors leading to increased risk of mortality for HF and SCD were identified. Future studies should determine whether targeting these factors decreases the risk of cardiac death., (Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objective: To describe the characteristics and determining factors of carer stress in a group of elderly home care patients with dementia evaluated in a Geriatric Assessment Unit., Material and Methods: An observational descriptive cross-sectional study was conducted using an assessment of baseline characteristics of patients and carers. Estimation of caregiver burden was registered by validated scales: Goldberg Anxiety Scale (GAS), Goldberg Depression Scales (GDS), and Zarit Burden Scale (ZS)., Results: A total of 130 patients were included. No item related to dementia patients was associated with caregiver burden. A poor perception of health and quality of life by the caregivers were associated with anxiety risk, depression and burden. Attendance rates for primary care and lack of paid work outside the home were associated with both, depression (GDS>2) and anxiety (GAS>4). Carer age and a lower education were related to depression. Anti-inflammatory, anxiolytics and antidepressants consumption was associated with anxiety, and anti-inflammatory consumption with caregiver burden (ZS >47)., Conclusions: The profile of carers in our sample is comparable to that described in other national studies, but care time is longer. The target population is difficult to identify and in need of help. Although there is not a formal demand for help, we should be encouraged to develop new healthcare methods., (Copyright © 2013 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España. All rights reserved.)

Background: Transcatheter aortic valve implantation (TAVI) is the recommended therapy for patients with severe aortic stenosis who are not suitable candidates for surgery. The aim of this study was to describe early experience and long-term follow-up with the CoreValve self-expanding aortic prosthesis at 42 Ibero-American hospitals., Methods: Multiple centre observational study including 1220 consecutive patients with symptomatic severe aortic stenosis who are not suitable candidates for surgery and underwent transcatheter aortic valve implantation with the self-expanding Medtronic CoreValve System between December 2007 and May 2012., Results: The registry included 1220 consecutive patients with a mean age of 80.8 ± 6.3 years and a mean logistic euroSCORE of 17.8% ± 13%. The procedural success rate was 96.1%. Hospital mortality was 7.3% and combined end-point was 21.3%. Aortic regurgitation after TAVI was present in 24.5% (Sellers grade ≥ 2). The estimated 1-year and 2-year survival rates were 82.1% and 73.4% respectively. The following issues were significant independent risk factors for hospital mortality: acute kidney failure (odds ratio 3.55); stroke (odds ratio 5.72); major bleeding (odds ratio 2.64) and euroSCORE (odds ratio 1.02). Long-term predictors of mortality were diabetes mellitus (hazard ratio 1.59, 95% confidence interval 1.09-2.31), severe chronic obstructive pulmonary disease (hazard ratio 1.85, 95% confidence interval 1.85-2.88), and functional classes NYHA III-IV (hazard ratio 1.31, 95% confidence interval 1.01-1.70)., Conclusions: Transcatheter aortic valve implantation constitutes a safe and viable therapeutic option for high operative risk patients with severe aortic stenosis. Long-term prognosis is conditioned by associate comorbidities., (© 2013.)

Objectives: This study sought to evaluate the main baseline and procedural characteristics, management, and clinical outcomes of patients from a large cohort of patients undergoing transcatheter aortic valve implantation (TAVI) who suffered coronary obstruction (CO)., Background: Very little data exist on CO following TAVI., Methods: This multicenter registry included 44 patients who suffered symptomatic CO following TAVI of 6,688 patients (0.66%). Pre-TAVI computed tomography data was available in 28 CO patients and in a control group of 345 patients (comparisons were performed including all patients and a cohort matched 1:1 by age, sex, previous coronary artery bypass graft, transcatheter valve type, and size)., Results: Baseline and procedural variables associated with CO were older age (p < 0.001), female sex (p < 0.001), no previous coronary artery bypass graft (p = 0.043), the use of a balloon-expandable valve (p = 0.023), and previous surgical aortic bioprosthesis (p = 0.045). The left coronary artery was the most commonly involved (88.6%). The mean left coronary artery ostia height and sinus of Valsalva diameters were lower in patients with obstruction than in control subjects (10.6 ± 2.1 mm vs. 13.4 ± 2.1 mm, p < 0.001; 28.1 ± 3.8 mm vs. 31.9 ± 4.1 mm, p < 0.001). Differences between groups remained significant after the case-matched analysis (p < 0.001 for coronary height; p = 0.01 for sinus of Valsalva diameter). Most patients presented with persistent severe hypotension (68.2%) and electrocardiographic changes (56.8%). Percutaneous coronary intervention was attempted in 75% of the cases and was successful in 81.8%. Thirty-day mortality was 40.9%. After a median follow-up of 12 (2 to 18) months, the cumulative mortality rate was 45.5%, and there were no cases of stent thrombosis or reintervention., Conclusions: Symptomatic CO following TAVI was a rare but life-threatening complication that occurred more frequently in women, in patients receiving a balloon-expandable valve, and in those with a previous surgical bioprosthesis. Lower-lying coronary ostium and shallow sinus of Valsalva were associated anatomic factors, and despite successful treatment, acute and late mortality remained very high, highlighting the importance of anticipating and preventing the occurrence of this complication., (Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Introduction and Objectives: There is little information on the use of transcatheter aortic valve implantation in patients with severe aortic stenosis and porcelain aorta. The primary aim of this study was to analyze death from any cause after CoreValve(®) implantation in patients with severe aortic stenosis, with and without porcelain aorta., Methods: In this multicenter, observational prospective study, carried out in 3 hospitals, percutaneous aortic valves were implanted in 449 patients with severely calcified aortic stenosis. Of these, 36 (8%) met the criteria for porcelain aorta. The primary end-point was death from any cause at 2 years., Results: Patients with porcelain aorta more frequently had extracardiac vascular disease (11 [30.6%] vs 49 [11.9%]; P=.002), prior coronary revascularization (15 [41.7%] vs 98 [23.7%]; P=.017), and dyslipidemia (26 [72.2%] vs 186 [45%]; P=.02). In these patients, there was greater use of general anesthesia (15 [41.7%] vs 111 [16.9%]; P=.058) and axillary access (9 [25%] vs 34 [8.2%]; P=.004). The success rate of the procedure (94.4 vs 97.3%; P=.28) and the incidence of complications (7 [19.4%] vs 48 [11.6%]; P=.20) were similar in both groups. There were no statistically significant differences in the primary end point at 24 months of follow-up (8 [22.2%] vs 66 [16%]; P=.33). The only predictive variable for the primary end point was the presence of complications during implantation (hazard ratio=2.6; 95% confidence interval, 1.5-4.5; P=.001)., Conclusions: In patients with aortic stenosis and porcelain aorta unsuitable for surgery, percutaneous implantation of the CoreValve(®) self-expanding valve prosthesis is safe and feasible., (Copyright © 2013 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.)

We present a model of single species fishery which alternates closed seasons with pulse captures. The novelty is that the length of a closed season is determined by the remaining stock size after the last capture. The process is described by a new type of impulsive differential equations recently introduced. The main result is a fishing effort threshold which determines either the sustainability of the fishery or the extinction of the resource., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background: University students are especially vulnerable towards substance abuse, Aim: To describe and compare drug consumption in students of a Chilean university who attended first and fourth year of studies, according to gender and faculty., Material and Methods: A representative, stratified and proportional sample of 305 students was randomly chosen by faculty, career, grade and gender during 2009. The consumption of alcohol, tobacco and illicit drugs was evaluated using an anonymous survey., Results: Students from health care faculties had the lower prevalence of consumption of tobacco, alcohol, tobacco-alcohol and marijuana, during the first and fourth year. Education area and social sciences faculties had the highest prevalence of consumption. Fourth year students had higher rates of consumption than their first year counterparts. Females had significantly lower rates of alcohol and marijuana consumption., Conclusions: Alcohol, tobacco and marijuana consumption was higher among students from education and social sciences faculties and those attending the fourth year of studies.

Background: Atrioventricular (AV) block is one of the most frequent complications of CoreValve transcatheter aortic valve implantation (TAVI). The aim of this study was to analyze the effects of CoreValve implantation on AV conduction., Methods and Results: Electrophysiological study was performed immediately before and after CoreValve implantation in 18 consecutive, permanent pacemaker-free patients. An electrode was placed on the His bundle during valve implantation, and data were continuously recorded during the procedure. With surface ECG, a median (first, third quartile) QRS width of 96 (84, 116) to 150 (121, 164) ms (P=0.001) and PR interval of 180 (159, 216) to 210 (190, 240) ms (P=0.008) were significantly prolonged, and QRS axis was left deviated 30° (-32°, 46°) to -20° (-60°, 2°) (P=0.005). With intracardiac electrograms, the AH (97 [70, 123] to 115 [96, 135] ms, P=0.021) and HV (52 [42, 55] to 60 [50, 70] ms, P=0.002) intervals were increased. At the end of the procedure, we observed significant ECG- or electrophysiological study-persistent conduction disturbances in 14 (78%) patients. Five patients experienced transient changes (2 AV blocks and 3 left bundle branch blocks)., Conclusions: CoreValve implantation worsens AV conduction in most patients, either transiently or permanently. This worsening is the result of direct damage either on the His bundle or on the AV node.

Introduction and Objectives: Transfemoral implantation of an Edwards SAPIEN (ES) or Medtronic CoreValve (MCV) aortic valve prosthesis is an alternative to surgical replacement for patients with severe aortic stenosis and a high surgical risk. The study's aim was to compare results obtained with these two devices., Methods: Prospective observational study of transfemoral prosthesis implantation performed at our center., Results: Of the 76 patients (age 83 ± 6 years, 63% female, logistic EuroSCORE 18 ± 9) included, 50 were assigned the ES and 26 the MCV device. There was no difference between the groups in age, sex, functional class, valve area, associated conditions, or EuroSCORE. Implantation was successful in 84% of the ES group and 100% of the MCV group (P = .04). There were three cases of tamponade, two aortic dissections and one valve malposition in the ES group. The two groups had similar vascular access complication rates (26% vs. 23%; P=NS), but pacemaker need was greater with the MCV (10% vs. 39%; P = .003). Mortality rates at 30 days were 12% and 20% (P = NS) in the ES and MCV groups, respectively, and at 1 year, 24% and 20% (P = NS), respectively. After a follow-up of 367 ± 266 days in the ES group and 172 ± 159 days in the MCV group, three patients died. Clinical improvement was maintained in other patients and no echocardiographic changes were observed., Conclusions: In-hospital mortality, the complication rate and medium-term outcomes were similar with the two devices. The only difference observed was a higher implantation success rate with the MCV, although at the expense of a greater frequency of atrioventricular block., (Copyright © 2010 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.)

Aims: To validate and test in vivo a new modality of quantitative coronary angiography (QCA), dual QCA (D-QCA), developed to quantify intracoronary thrombotic burden (ITB)., Methods and Results: Calculation of ITB with D-QCA is based on the discrepancy of luminal areas assessed with edge detection (ED) and video-densitometry (VD), measured with Cardiovascular Angiography Analysis System II. Experimental validation was first performed in phantoms with known obstructive volumes. In vivo assessment of thrombotic burden changes was performed in angiograms from 19 patients with large ITB, obtained before and after antithrombotic treatment, and compared with semi-quantitative assessment (TIMI thrombus grade (TTG)). A good correlation between D-QCA and true occlusive volumes was found (y = 9.21+0.99x, r = 0.996). Intra- and inter-observer variability was 2.77 +/- 10.97 mm3 (p = 0.50) and -1.28 +/- 6.99 mm3 (p = 0.62) respectively. In vivo, D-QCA demonstrated a significant reduction in ITB resulting from treatment (137.22 +/- 120.13 mm3 before and 104.72 +/- 99.19 mm3 after treatment, p = 0.001). Overall, TTG also decreased (3.63 +/- 0.68 before and 3.11 +/- 1.20 after, p = 0.008), but in those nine (47%) patients in which remained unchanged D-QCA detected a reduction in ITB (pre 148.17 +/- 154.03 mm3, post 112.86 +/- 117.82 mm3, p = 0.05)., Conclusions: D-QCA appears as a useful approach to quantify IC thrombus volume, being more sensitive than TTG in assessing changes in ITB resulting from treatment strategies.

Purpose: Cross-sectional study to validate a Spanish version of the 5 and 15 items Geriatric Depression Scale (GDS 5 and 15) in a non-selected community dwelling older population, compared with the clinical diagnosis of depression (using DSM-IV criteria) as gold standard., Patients and Method: A total of 301 subjects randomly selected from the >64 years old population served by a public Primary Care Center in Madrid were included. Severe cognitive impairment (MMSE < 20/30), severe hearing impairment and denial to participate were exclusion criteria. A descriptive and a screening study were performed., Results: The prevalence of depression in this population was 14.6%. The 5- item GDS had a sensitivity of 0.864 (0.762-0.965), specificity of 0.856 (0.813-0.899), PPV 0.507 (0.394-0.62), NPV 0.973 (0.952-0.994), and positive likelihood ratio 6 (4.34-8.26). The 15-item GDS had a sensitivity of 0.818 (0.704-0.932), specificity of 0.977 (0.958-0.995), PPV 0.857 (0.751-0.963), NPV 0.969 (0.948-0.99), and positive likelihood ratio 35.03 (28.76-40.77)., Conclusions: GDS-5 may be useful screening test for depression in non selected elderly patients in primary care. It has better sensitivity than GDS-15 and similar area under curve.

Cervical carotid artery dissections (CCAD) are common in young adults with a mean age of 44 years and may account for as many as 20% of strokes in patients younger than 30 years. Trauma and primary diseases of the arterial wall such as fibromuscular dysplasia are the main predisposing factors. Some CCAD cases are diagnosed solely on clinical history and physical examination, and even imaging tools such as helical/multi-slice computed tomography (CT) and magnetic resonance imaging (MRI) sometimes are not sufficient to reach a diagnosis. We describe the case of an 18-year-old male who presented to our emergency department due to loss of consciousness 18 hours after a car accident. Previously he had been in no acute distress, with fluent speech, and able to follow 3-step commands. Helical CT showed a hypodense lesion in the left-middle cerebral artery territory, as well as hyperdensity of the M1 segment of the middle cerebral artery. Cerebral angiography depicted the left carotid artery dissection in the C1 segment. Physicians should consider this entity in "asymptomatic" patients during their first hours after head injury, among patients who later develop focal neurological symptoms and clinical deficits. Clinical suspicion followed by radiological findings allows early neurovascular treatment, trying to save viable brain tissue in the first hours post injury.

Object: Volume estimation is one of the most important criteria in the evaluation and follow up of radiosurgical treatments and outcomes; however, several limitations are involved in the calculation estimation of target volumes., Methods: Retrospective and prospective studies were conducted to evaluate the efficacy of a new noninvasive stereotactic method when it is compared with geometric volume calculation of intracranial tumors for planning stereotactic radiosurgery treatment as well as for follow up and outcome evaluation. Two equations were created that permit comparison of the calculated and measured volumes. These equations took linear and quadratic forms, respectively. Volume estimation using the stereotactic approach compared with traditional volume calculation gave more accurate results regardless of the shape and size of the lesion., Conclusions: The use of stereotactic volume calculation is highly recommended in planning, follow up, and determination of the outcome in patients participating in radiosurgical treatment and should lead to more uniform reports of the response to treatment.

Objective: To find just how suitable thromboembolism prophylaxis (TEP) is in a group of patients with chronic auricular fibrillation belonging to the primary care environment., Design: Cross-sectional and descriptive multi-centre study., Setting: The study was performed at 3 urban primary care centres in Madrid., Participants: All the patients recorded up to April 2001 with the diagnosis of chronic auricular fibrillation (n=274) were included. Patients with no clinical history or who had a valve prosthesis were excluded., Main Measurements: Demographic variables, existence of factors of risk of embolism, presence of counter-indications for oral anti-coagulants, and the kind of thromboembolic prophylaxis taken were collected., Results: A total of 274 patients were evaluated. Average age was 75 (SD, 9) and 52% were women. 82% of patients had at least one factor of risk of thromboembolism. The most commonly used kind of TEP was oral anti-coagulants. 45% of patients did not receive suitable TEP. 13.5% of patients at risk of embolism and who had no kind of TEP were found., Conclusions: There is a high percentage of patients with chronic auricular fibrillation and a high risk of embolism, who do not receive adequate TEP, in the absence of counter-indications to taking oral anticoagulants. There is great scope for improvement, which is within professionals' possibilities.

The authors report on the case of a 38-year-old woman who had experienced incapacitating pulsatile tinnitus in the left ear for 6 months. Angiographic studies revealed a wide-necked venous aneurysm of the left transverse-sigmoid sinus. Solitary stent placement across the aneurysm neck resulted in a slight modification in the lesion's characteristics. A second session, in which embolization with Guglielmi Detachable Coils was performed, resulted in a 100% occlusion of the aneurysm, with patency of the parent vessel and resolution of the tinnitus.

When the essential and distinctive cell walls of either pathogenic or nonpathogenic fungi break, cytoplasmic membranes rupture and fungi die. This fungicidal activity was discovered previously on nonproliferating Saccharomyces cerevisiae cells treated briefly with the oxidative tool and anticancer drug family of bleomycins. The present studies investigated effects of bleomycin on growing fungal organisms. These included the medically important Aspergillus fumigatus and Cryptococcus neoformans, as well as the emerging human pathogen and fungal model, S. cerevisiae. Bleomycin had its highest potency against A. fumigatus. Scanning electron microscopy and thin-section transmission electron microscopy were used to study morphological growth characteristics. Killing and growth inhibition were also measured. Long, thin, and segmented hyphae were observed when A. fumigatus was grown without bleomycin but were never observed when the mold was grown with the drug. Bleomycin arrested conidial germination, hyphal development, and the progression and completion of cell wall septation. Similarly, the drug inhibited the construction of yeast cell wall septa, preventing cytokinesis and progression in the cell division cycle of S. cerevisiae. Even when cytoplasms of mother and daughter cells separated, septation and cell division did not necessarily occur. Bizarre cell configurations, abnormally thickened cell walls at mother-daughter necks, abnormal polarized growth, large undivided cells, fragmented cells, and empty cell ghosts were also produced. This is the first report of a fungicidal agent that arrests fungal growth and development, septum formation, and cytokinesis and that also preferentially localizes to cell walls and alters isolated cell walls as well as intact cell walls on nongrowing cells.

Objectives: To find the number of patients seen in casualty who received gastropathy prophylaxis with NSAIDs that complied with the pharmaco-therapeutic guidelines of the health district., Design: Descriptive study of technical-scientific quality., Setting: The Casualty Department of the Ramón y Cajal hospital., Participants: Randomised sample of 400 emergencies attended in January 1999 and 2000, excluding paediatric cases, people previously treated with gastro-protectors, patients admitted and the deceased. Main measurements. On the basis of casualty records: suitability of indication and criteria used; if unsuitable, how; adequacy of selection of the principle, patient' age and sex, digestive pathology history, area and year of care., Results: NSAIDs were prescribed in 37.9% of cases (33.27-42.79), with prescription unsuitable in 21.19% (15.2-28.3). 15% (9.5-22) were unsuitable by default; and 54.2% (35.1-72.1), by excess. Unsuitability was greater among women, if there was history of digestive pathology, and among older people, with no differences found for area or year of care. The choice of gastric protector was not suitable in any case., Conclusions: Given the amount of primary care prescription originating in hospital casualty departments, and its effect on the training of family medicine interns, strategies coordinated between health care levels must be introduced in order to improve gastric protection prescription in NSAID gastropathy prophylaxis. The effectiveness of these strategies must be evaluated.

Objectives: To evaluate the utility of C-reactive protein (CRP) in the detection of necrosis in acute pancreatitis and to determine the best cut-off point for CRP used for this purpose., Material and Methods: We performed a retrospective study of 157 patients with acute pancreatitis who underwent computed tomography (CT) with intravenous contrast material between 72 h and 8 days after the onset of symptoms and whose serum CRP values were determined by nephelometry 24 h or later after the onset of pain., Results: Ninety-four patients were men and 63 were women, with a mean age of 61 years (range, 15-96 years). The cause of pancreatitis was biliary lithiasis in 53.5%, alcohol in 20.4%, and idiopathic in 10.8%. Other causes were found in 15.3%. The mean (standard deviation) time elapsed between symptom onset and extraction to evaluate CRP was 3.21 (1.7) days. The patients were divided into two groups according to the results of CT: 132 patients with acute intersitial edematous pancreatitis and 25 patients with acute necrotizing pancreatitis. The mean CRP concentrations were: 322 mg/l (range, 10.7-538) in patients with acute necrotizing pancreatitis and 133 mg/l (range, 3-442) in those with acute interstitial pancreatitis; this difference was statistically significant (p < 0.001). The area under the ROC curve of CRP vs. the occurrence of necrosis was 0.862 (95% CI, 0.778, 0.946). To evaluate the presence of pancreatic necrosis a cut-off level of 200 mg/l showed a sensitivity of 88% and a specificity of 75% while a cut-off level of 279 mg/l presented a sensitivity of 72% and a specificity of 88%., Conclusions: In acute pancreatitis, a CRP value of less than or equal to 200 mg/l obtained at 72 h of symptom onset is useful for ruling out, with a high degree of probability, the presence of necrosis. With higher values, additional investigations should be performed to determine the presence of pancreatic necrosis; nevertheless, with values higher than 279 mg/l the risk of necrosis markedly increases.

Background: It has been traditionally accepted that ophthalmologic alterations in cases of primary empty sella syndrome are caused by the herniation of the visual system in the pituitary fossa, but this cannot be stated categorically., Methods: Two female patients with primary empty sella syndrome and visual field defects were included in this series. The peculiarity of these cases was that in neither of them was there an evident herniation of the visual system. In the absence of other causes that could explain the visual defects, the patients were operated on through a transsphenoidal approach., Results: Both patients showed immediate improvement of their visual deficits without recurrence. Postoperative imaging studies have shown continuance of an adequate elevation of the sellar contents during the 5-year follow-up period., Conclusions: Visual field defects in cases of primary empty sella syndrome may occur even without radiological evidence of herniation of the visual system. The fact that the two patients described in this paper improved after surgery supports other reports that in this syndrome traction on the infundibular stalk may cause some microscopic anatomic alteration in the visual system or in its vascular supply that is not evident on imaging studies.

Objective: To find scientific evidence to support the indication for treating outbreaks in COPD patients on an out-patient basis with levofloxacine, as against conventional treatments., Design: Standardised review, following the criteria of medicine based on the evidence. A bibliographic search of the MEDLINE data base from 1966 to June 2000 was the basis for an analysis of the evidence found., Setting: Non-hospital treatment., Patients and Other Participants: COPD patients suffering a light outbreak of probable bacterial origin, according to the Anthonisen criteria., Interventions: The intervention analysed was treatment with 500 mg/day of levofloxacine taken orally. An attempt was made to compare this with conventional treatments such as amoxycillin-clavulanic acid and acetyl cefuroxime. The indicators of results analysed were reduction in mortality or in the number of hospital admissions., Measurements and Main Results: No clinical trial was found that compared levofloxacine and amoxycillin-clavulanic acid. Two clinical trials were found that compared levofloxacine and acetyl cefuroxime. These found no significant differences between the group treated with levofloxacine and the group treated with cefuroxime., Conclusions: No scientific evidence demonstrating advantages of levofloxacine treatment over amoxycillin-clavulanic acid was found, or over acetyl cefuroxime as empirical PC first-choice treatment for patients with outbreaks of COPD.

Three experiments studied the effectiveness of ketamine acting as an aversive unconditioned stimulus (UCS) in a conditioned flavor aversion procedure. In Experiment 1a, three conditioning trials where sucrose was paired with ketamine produced a weak but significant aversion to sucrose; Experiment 1b showed that this effect was not due to a reduced consumption of sucrose caused by ketamine-induced neophobia. In Experiment 2, acquisition of an aversion to sucrose paired with lithium chloride (LiCl) injections was retarded by prior repeated exposure to LiCl but not to ketamine. These results are not consistent with an interpretation of previous results, showing that ketamine impairs the acquisition of flavor aversions based on LiCl-induced illness, as an example of the UCS preexposure effect.

Mechanical ventilation of the lungs is an integral component of modern medical practice in the operating room and intensive care unit settings. Most ventilators available in the operating room are capable of providing only controlled mechanical ventilation. With the increasing use of the microprocessor-controlled ventilators in the intensive care unit, there are now a wide variety of ventilatory types and mode choices available to the clinician. This paper summarizes some of the ventilatory choices currently available and mentions some of the newer and experimental modalities available in larger centers.

Specific groups of sea anemone and scorpion toxins compete on the same pharmacological site, on the voltage-gated sodium channel of mammal excitable membranes. However, these scorpion and sea anemone toxins are two distinct protein families. Here we purified and sequenced a new sea anemone toxin, Bg II, highly toxic to mammals and also a less toxic mutant, Bg III. Two Bg II models were determined from sequence homologies with two sea anemone toxin two-dimensional NMR structures. Only one model conformed to circular dichroism data obtained from Bg II and was compared with an x-ray structure of a scorpion toxin. The comparison of the two structures shows that 5 amino acid residues are located similarly in the sea anemone toxin and the scorpion toxin. From these 5 residues, 4 are basic residues, constituting two distinct positively charged poles on the surface of these toxins. In the sea anemone mutant isolated, a negative charge beside one of the positive poles decreases the toxicity. These results show that positively charged amino acid residues could be essential for the activity of these toxins and outline the role of electrostatic bonds in the interaction of sea anemone and scorpion toxins with their receptor.

In four experiments with rats, the effects of the NMDA antagonist ketamine on several forms of gustatory learning were studied. Replicating previous findings, in Experiment 1 ketamine was shown to impair one-trial acquisition of a flavor aversion at the dose of 25 mg/kg, but also produced a significant state-dependency effect. In Experiment 2 ketamine did not alter the process of habituation of neophobia to a new flavor. Abolition of latent inhibition by ketamine injected before preexposure in Experiment 3a was not replicated in Experiment 3b when ketamine was injected before all phases of the experiment. Finally, in Experiment 4 rats injected with ketamine showed slower acquisition of a flavor aversion with a multiple-trial procedure but finally reached a level similar to that shown by saline controls. The implications of these results for an interpretation of the effects of ketamine on flavor aversion learning in terms of interference with flavor memory storage are discussed.

We review the pathological specimens sent to the Pathology Department from January 1983 to June 1988 that belonged to 7567 patients. For this study we have selected specimens from 1139 patients (15.05% of the total), who were submitted to valvular replacement surgery. We analyzed 1037 "native" valves and 186 prosthesis. Rheumatic fever was confirmed in 68% of "native" valves. The remaining 32% includes a group in which this etiology was not confirmed by histology in spite of the clinical diagnosis. The leading cause of biological prosthesis replacement was dysfunction caused by calcification and fibrosis, and for mechanical prosthesis it was thrombosis. Included in this study are 747 patients who received 836 heterologous valves of bovine pericardium, fabricated at the "Instituto Nacional de Cardiología (INC)". The price of imported mechanical prosthesis is superior to the price of the prosthesis manufactured at INC. The difference varies between 1400% and 4000% depending on mechanical prosthesis type. The survival rate of the receiving patients of the INC implants was 82.2%, and the dysfunction rate of these prosthesis was 3.38% for the period studied, four and a half years.

A case of small and large cells non Hodgkin lymphoma with an unusual involvement of the lung is presented. The tumor was located in the inferior lower lobe of the right lung and coincided with hemorrhagic pleural effusion. The cytopathological study of the fluid was negative for neoplastic cells, so were the aspiration biopsy of the lung and the pleural biopsy. The transmission and scanning electron microscopic study of the pleural fluid demonstrated lymphoid atypical cells. The patient was treated by resection of the lower right lobe and pleurectomy. The difficulties in the differential diagnosis of this type on non Hodgkin lymphoma are discussed. The importance of scanning and transmission electron microscopy is stressed when the light cytologic studies are negative in processes suggestive of being neoplasms. After one year of the lobectomy and treatment with vincristine-epirubicin-cyclophosphamide and methyl-prednisolone, the patient is in good condition without evidence of neoplastic activity.

An ATPase co-sedimenting with rat liver peroxisomes has been detected after subcellular fractionation. The activity is Mg2+ dependent, with pH optimum of 7.5 and is inhibited by NEM and DCCD but not by oligomycin. Partial inhibition of the mitochondrial ATPase allows to detect the peroxisomal activity in the gradients. Protease inactivation and solubilization data suggests that the activity resides in a protein of the peroxisomal membrane, exposed to the cytosol.

The severity and prevalence of coronary and aortic atherosclerosis was studied in 174 subjects who died from violent causes in Mexico City. As in other geographic areas, fatty streaks were found early in life (12 years old). Fibrolipid plaques were present in the thoracic aorta at age 15 and at age 19 in the abdominal segment. Complicated lesions were detected in the aorta after age 25. Because of the obvious clinical significance we looked for severe aortic lesions in the abdominal bifurcation. The prevalence of severe lesions in the bifurcation was 0 between 15 to 24 years and raised to 23.3% in the 45-54 age group. A moderate correlation was found between the severity of coronary and aortic lesions. The discordance most often found was the presence of severe coronary lesions without severe aortic involvement.

The presence of rigid coronary arterial segments was detected during a survey for coronary atherosclerosis in men who died of violent causes. These lesions which traditionally are considered of non-clinical significance, in the absence of stenosis are probably responsible of the clinical and electrocardiographical abnormalities as seen in patients with "normal" coronary arteries using coronary angiography, the best current procedure for the detection of isolated coronary atherosclerosis. We propose these lesions are to be considered as functional lesions and consequently that these lesions should be considered by both, the pathologist and the clinician. Our hypothesis is to be tested in the near future when new diagnostic advances with the possibility of detection of coronary pathology in vivo, appear. The prevalence of these abnormalities in different age-groups as well as the topography are presented. The concordance of these lesions with coronary stenosis is also presented.

This report compares quantitative measures of atherosclerosis in aortas and coronaries from autopsies of deceased men from Mexico City collected during 1960 to 1964 and 1986 to 1987. The comparison of lesions in two different time periods provides an opportunity for determining whether the extent of atherosclerosis has changed over time in Mexico City. Three pathologists independently evaluated the extent of fatty streaks (FS), fibrous plaques (FP), calcified plaques (CA), and complicated lesions (CO) in 165 aortas and 120 sets of coronary arteries collected during 1986 to 1987 for comparison with similar gradings of 128 aortas and coronary arteries from the International Atherosclerosis Project in 1960 to 1964. Neither FS nor more advanced lesions differed significantly in either the descending thoracic or abdominal aorta between the two collection periods. In contrast, there were more extensive FP and raised atherosclerotic lesions (RL = FP + CA + CO) in the coronary artery segments evaluated in the younger age groups in 1986 to 1987 versus 1960 to 1964. Additional analyses, based on 75 pairs of aortas and 32 pairs of coronary arteries from age-matched cases, all regraded by the team of pathologists after blind coding, showed more FS in both aortic segments and more extensive involvement with RL in the three main branches of the coronary arteries in the more recent study. An overview of our findings suggests that atherosclerosis, particularly in the coronary arteries, is increasing in Mexico City. This hypothesis merits careful testing in parallel with consideration of possible changes in the risk factors that could be responsible for changes in extent of lesions.

Topographic and morphologic aspects of coronary atherosclerotic "protruding" lesions were investigated in 119 accidental deaths in males living in Mexico City. Morphology and topography varied according to the arterial trunk studied and age. Left anterior descending and circumflex lesions were almost always confined to the initial 5 cms and if a lesion was present after the 3rd cm there was always a proximal lesion. Right coronary lesions occasionally were found distally even in the absence of proximal lesions. Third decade lesions were usually not calcified. Stenosis if present was rarely multivascular. Some fourth decade lesions were calcified; plurivascular stenosis was present in some cases. Fifth decade lesions show sequential stenotic lesions in the same vessel; calcium and plurivascular stenosis were often observed. However the features observed in the 3rd decade could be observed in the older subjects. Reference is made to lesions which are found in both the left main trunk and the left anterior descending. Epidemiological and clinical applications related with preventive programs are mentioned.

For clinicians, cardiac myxomas has been a diagnostic challenge. It may simulate a valvular disfunction. The present paper displays the morphologic aspects on 17 patients with the diagnosis of atrial myxoma. In 14 cases the tumor was located in the left atrium. In all the cases stellate shaped cells were seen within a myxoid matrix. The findings in this report support the idea that myxomas are tumors and not thrombi as it has been speculated in the literature. We also consider that the cell of origin of this neoplasm is a pluripotential cell which needs further studies.

Intramitochondrial lamellar bodies were observed in three cases of acute myeloblastic leukemia. Two of the patients had M1 leukemia and the remaining patient M4 leukemia, by the FAB classification. In all three cases neoplastic cells contained dilated mitochondria that varied in size and shape and contained decreased numbers of cristae. Some mitochondria contained lamellar structures that resembled myelin figures and, occasionally, primary granules; these structures were more conspicuous in the central portion of the mitochondria. Regardless of the proliferating cell type (lymphoblasts, myeloblasts, or monoblasts), there are common ultrastructural changes that represent abnormal metabolic function, such as disorders of intramitochondrial protein synthesis. The exact meaning of these findings is not known; adequate interpretation will require further investigation of the biology of these neoplastic processes.

The prevalence of microscopic atheroma in the proximal left anterior descending coronary artery was studied in thirty young males aged 20 to 29 years, living in Mexico City, who died in urban accidents. All of them were either unemployed or labor workers with a socioeconomical status considered to be representative of the majority of young males living in Mexico City. It was found that coronary atheroma was present in 11 of them (33%) with variable degrees of luminal obstruction. In two of them the luminal obstruction was greater than 75%. The prevalence found in this group was significantly different to that found in younger and older males who also died in accidents. Since the prevalence of coronary atheroma was not related to ventricular hypertrophy, valvular or congenital heart disease our findings indicate that in Mexico City as in other geographical regions, coronary atherosclerosis is not an unusual finding in males in the third decade of life, with a low socioeconomical status.