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Biomedical subjects

M Velasco

Publications and source records attributed to M Velasco.

At least 19 recordsLinked to original sources
PubMed2006

Mortality among adult patients admitted to the hospital on weekends.

BACKGROUND: Some reports have shown that the risk of death is higher for patients admitted on weekends than for patients who go into the hospital on weekdays. This study was conducted to assess what independent influence, if any, weekend admission might have on mortality in our hospital. METHODS: The clinical data of 35,993 adult (>14 years) patients admitted to the emergency department of Fundación Hospital Alcorcón from 1999 to 2003 were analyzed. We compared global mortality and mortality within the first 48 h according to whether the patients were admitted on the weekend or on a weekday. Elective admissions, critical care patients, children under 14 and births were not included. RESULTS: Global mortality was similar in both groups, but mortality within the first 48 h was higher for patients admitted on the weekend (OR 1.40, 95% CI 1.18-1.62, P<0.001), even after controlling for age, gender and comorbidity (weight of diagnosis-related group and Charlson comorbidity index). CONCLUSION: The risk of mortality within the first 48 h is higher for patients admitted on weekends than for patients admitted on a weekday.

Journal Article↗
PubMed2006

Routine use of auxiliary partial orthotopic liver transplantation for children with fulminant hepatic failure: Preliminary report.

Auxiliary partial orthotopic liver transplantation (APOLT) has been performed for both metabolic disorders and fulminant liver failure (FHF). When the native liver regenerates, the patients with FHF who undergo APOLT have a chance to withdraw immunosuppression. It may be most beneficial for children. This preliminary report describes our start to routinely offer APOLT as an option to standard OLT for children with FHF in 2005. Six children (ages 8 months to 8 years) received APOLT: 1 in 1996 and the others in 2005 and 2006. The donor ages ranged from 4 to 40 years. We used either a left lateral segment or a left lobe graft. The recipient left lobe, which was removed, showed submassive to massive necrosis at the time of transplantation. All children are alive and well. The first patient who received APOLT in 1996 is currently off immunosuppression with a fully recovered native liver; the grafted liver underwent complete atrophy. The 5 remaining subjects are receiving reduced levels of immunosuppression with close monitoring. Their serial liver biopsy specimens show slight to significant recovery. One developed hepatic artery thrombosis, requiring retransplantation. The native liver was retained at the time of retransplantation (redo APOLT). Other postoperative complications included a bile leak (n = 1), invasive mucomycosis of the arm (preexisting condition; n = 1), biliary stricture (n = 1), and acute cellular rejection (n = 3). Posttransplantation length of stay was 6 to 60 days (median, 15 days). In conclusion, APOLT can be safely performed in children with FHF displaying short-term outcomes comparable to standard transplantations.

Adolescent↗
PubMed2006

ATM gene expression is associated with differentiation and angiogenesis in infiltrating breast carcinomas.

UNLABELLED: The product of the ATM gene, mutated in the human genetic disorder ataxia-telangiectasia (A-T) plays a key role in the detection and repair of DNA double-strand breaks. A-T is defined by progressive cerebellar ataxia, telangiectasia, sensitivity to ionising radiation and genomic instability with cancer predisposition. On the other hand, increased angiogenesis is essential for tumor growth and metastasis. The aim of this study was to investigate ATM expression in breast carcinomas and its relationship to neoangiogenesis. METHODS AND RESULTS: Fifty-two breast tumors from 51 patients, 38 of them with concomitant in situ component (CIS), were analyzed by immunohistochemistry for the expression of ATM. CD34 expression was used for the morphometric evaluation of vasculature. ATM was positive in 1 to 10% of normal epithelial cells. ATM expression was reduced in 55.8% of infiltrating carcinomas, non-reduced in 34.6%, and increased in 9.6%. Expression of ATM in CIS was similar to the infiltrating component in 71% of cases and reduced in 23.7% of them. High-grade ductal infiltrating carcinomas showed lower ATM expression than low-grade ones. Reduced ATM expression also correlated with increased microvascular area. CONCLUSIONS: Reduced ATM expression in breast carcinomas correlated with tumor differentiation and increased microvascular parameters, supporting its role in neoangiogenesis and tumor progression in breast carcinogenesis.

Antigens, CD34↗
PubMed2006

Evaluation of a rapid culture method for tuberculosis diagnosis: a Latin American multi-center study.

SETTINGS: Tuberculosis (TB) diagnostic laboratories in Latin America. OBJECTIVES: Evaluation of thin-layer agar (TLA) compared to Löwenstein-Jensen (LJ) culture for the diagnosis of TB. DESIGN: Phase II prospective study in six laboratories. Samples included sputum and extra-pulmonary specimens from patients with a clinical diagnosis of TB. Respiratory samples were decontaminated using NaOH/ NALC; all samples were centrifuged, stained with Ziehl-Neelsen for acid-fast bacilli (AFB), cultured on LJ and TLA and identified according to recommended procedures. Sensitivity and likelihood ratios (LR), growth detection time and contamination rate were calculated for both media. RESULTS: A total of 1118 clinical specimens were studied. Cultures detected Mycobacterium tuberculosis in all AFB-positive samples, whereas for AFB-negative specimens LJ detected 3.2% and TLA 4.4%. Sensitivity was 92.6% (95%CI 87.9-95.9) and 84.7% (95%CI 78.8-89.0) for TLA and LJ, respectively. Positive and negative LRs were similar. Contamination was 5.1% for TLA and 3.0% for LJ. Median time to detection of a positive culture was 11.5 days (95%CI 9.3-15.0) for TLA and 30.5 days (95%CI 26.9-39.0) for LJ (P < 0.0001). CONCLUSION: Difference in the characteristics of the participating laboratories, the disease prevalence and the number and type of specimens processed did not affect the overall performance of TLA as compared to LJ, supporting the robustness of the method and its feasibility in different laboratory settings.

Agar↗
PubMed2005

Clinical axillary recurrence after sentinel node biopsy in breast cancer: a follow-up study of 220 patients.

PURPOSE: The aim of this study was to evaluate the frequency of false-negative (FN) sentinel node procedures in patients with breast cancer and the subsequent clinical outcome in such patients. METHODS: A total of 325 breast cancer patients underwent sentinel lymph node biopsy at our institution between June 1998 and May 2004. A 2-day protocol was used to localise the sentinel node with the injection of 99mTc-nanocolloid. There were two phases in the study: the learning phase (105 patients) and the application phase (220 patients). In the learning phase, a complete lymphadenectomy was always performed. In the application phase, sentinel nodes were studied intraoperatively and lymphadenectomy was performed when considered warranted by the pathological intraoperative results. RESULTS: The median follow-up duration in the 220 patients studied during the application phase was 21.2 months (range 4-45 months). In this phase a total of 427 sentinel nodes were obtained (range 1-5 per patient, median 1.99), with 66 positive sentinel nodes in 56 patients (26%). The lymphadenectomies performed were also positive in 25% of cases (14 patients). We observed a total of two false-negative sentinel lymph node results (3.45%). One of them was found during the surgical excision of non-sentinel nodes, and the other presented as an axillary recurrence 17 months postoperatively (1.72% clinical false-negative rate). The latter patient died 1 year after the first recurrence. CONCLUSION: After a median follow-up of 21.2 months we observed only one clinical recurrence among 220 patients. Our results indicate that adequate local control is achieved by application of the sentinel node protocol.

Adult↗
PubMed2005

Multicenter study of MTT and resazurin assays for testing susceptibility to first-line anti-tuberculosis drugs.

OBJECTIVE: A multicentre evaluation was performed to assess two rapid low-cost methods, MTT (3-[4.5-dimethylthiazol-2-yl]-2.5-diphenyltetrazolium bromide) and resazurin assays, for testing the susceptibility of Mycobacterium tuberculosis to the first-line anti-tuberculosis drugs rifampicin (RMP), isoniazid (INH), ethambutol (EMB) and streptomycin (SM). METHODS: Thirty coded M. tuberculosis strains were sent to seven laboratories located in Latin America, representing six countries. Each site performed the colorimetric assays, MTT and resazurin, blind for the first-line drugs RMP, INH, EMB and SM. The minimum inhibitory concentration results obtained were compared to the conventional proportion method on Lowenstein-Jensen medium. RESULTS: After establishing the breakpoint concentrations, excellent results were obtained for RMP, INH and EMB, with levels of specificity and sensitivity of between 96% and 99%. CONCLUSION: MTT and resazurin assays are promising, accessible new alternative methods for middle- and low-resource countries that need low-cost methods to perform rapid susceptibility testing of M. tuberculosis to key anti-tuberculosis drugs.

Antitubercular Agents↗
PubMed2004

Encephalopathy secondary to imipenem therapy.

We describe the case of an 84-year-old woman who developed a confusional state and suffered from a generalized tonic-clonic seizure while she was treated with imipenem, a beta-lactam antibiotic. Focal and generalized epileptiform discharges and a photoparoxysmal response were prominent with transient changes on the EEG.

Acinetobacter Infections↗
PubMed2003

[Theoretical model of a cost-effectiveness analysis of combined enalapril-nitrendipine therapy for treating hypertension].

OBJECTIVE: Cost-effectiveness analysis of combined enalapril-nitrendipine therapy (E/N), as second-line therapy for light or moderate hypertension. DESIGN: Theoretical model of cost-effectiveness, based on the norms of hypertension treatment in primary care, the considered view of a panel of experts and the direct costs of health resources and purchase of medication. SETTING: Spanish National Health system. PARTICIPANTS: Simulation of 1000 patients with hypertension, with a time horizon of one year. INTERVENTIONS: After a prior failure of the first-line treatment with either enalapril or nitrendipine, an evaluation was made of the possibilities of increasing dosage of the first-line treatment, changing the drug or administering the E/N combination. MAIN MEASUREMENT: The likelihoods, in the primary care context, of controlling diastolic pressure, of abandonment and of using the two strategies or not were measured, as were the use of health resources in each situation, and costs of resource use and of medication. RESULTS: The cost-effectiveness quotient of the combined E/N treatment was consistently more efficient than the increase in dose or change to another drug. This was so, whether the treatment was started with enalapril (301.06 euros vs 337.97 euros and 588.42 euros) or with nitrendipine (331.5 euros vs 469.88 euros and 579.76 euros). CONCLUSIONS: Combined therapy (E/N) is, on the basis of the assumptions made in the model, an efficient therapy option. Therefore, it can be recommended for prescription.

Cost-Benefit Analysis↗
PubMed2003

Community-acquired febrile urinary tract infection in diabetics could deserve a different management: a case-control study.

OBJECTIVE: To investigate if there are relevant differences in clinical, microbiological and outcome characteristics of community-acquired febrile urinary tract infection (UTI) between diabetic and nondiabetic patients. DESIGN: A prospectively matched case-control study. SETTING: An 800-bed tertiary care university-affiliated hospital. SUBJECTS: A total of 108 patients (54 diabetic and 54 nondiabetic patients matched by age and gender) admitted between January 1996 and September 1999 with febrile UTI. METHODS: Clinical, analytical, microbiological and outcome variables were analysed by means of McNemar test (categorical) or Wilcoxon matched pairs signed rank test (continuous). RESULTS: Mean age (SD) in both groups was 67.9 (14.4) years. In comparison with controls, diabetic patients were more likely to have fever without localizing symptoms (27% vs. 9%, P </= 0.0001), diminished consciousness level at admission (25% vs. 10%, P = 0.03), aetiological microorganism different from Escherichia coli (17% vs. 0, P = 0.0004), and quinolone-resistant bacteria (17% vs. 3.7%, P = 0.07). Duration of fever after the onset of treatment was 1.75 (1) days in diabetics and 1.5 (1.1) days in nondiabetics (P = 0.17). However, diabetic patients had a longer hospitalization [5.2 (3.3) days] than nondiabetics [3.9 (2.6) days, P = 0.006]. CONCLUSIONS: In diabetic patients, febrile UTIs have clinical and microbiological peculiarities that may have diagnostic and therapeutic implications.

Aged↗
PubMed2002

Dopamine, hypertension and obesity.

Dopamine, a neurotransmitter, precursor of noradrenaline, is responsible for cardiovascular and renal actions, such as increase in myocardial contractility and cardiac output, without changes in heart rate, producing passive and active vasodilatation, diuresis and natriuresis. These cardiovascular and renal actions take place through the interaction with dopamine receptors, D(1), D(2), D(3), D(4), and D(5). Recent findings point to the possibility of D(6) and D(7)receptors. Dopamine is known to influence the control of arterial pressure by influencing the central and peripheral nervous system and target organs such as kidneys and adrenal glands, in some types of hypertension. Although dopamine and its derivatives have been shown to have antihypertensive effects, these are still being studied; therefore it is important to explain some physiological and pharmacological aspects of dopamine, its receptors, and the clinical uses it could have in the treatment of arterial hypertension and more recently in obesity, based on evidence proving a clear association between obesity and the decrease in the expression of D(2) receptors in the brain of obese persons.

Angiotensin II↗
PubMed2002

Angiotensin II receptor antagonists role in arterial hypertension.

Angiotensin II receptor blockers represent a class of effective and well tolerated orally active antihypertensive drugs. Activation of AT(1) receptors leads to vasoconstriction, stimulation of the release of catecholamines and antidiuretic hormone and promote growth of vascular and cardiac muscle. AT(1) receptor blockers antagonise all those effects. Losartan was the first drug of this class marketed, shortly followed by valsartan, irbesartan, telmisartan, candesartan, eprosartan and others on current investigation. All these drugs have the common properties of blockading the AT(1) receptor thereby relaxing vascular smooth muscle, increase salt excretion, decrease cellular hypertrophy and induce antihypertensive effect without modifying heart rate or cardiac output. Most of the AT(1) receptor blockers in use controlled blood pressure during the 24 h with a once-daily dose, without evidence of producing tolerance to the antihypertensive effect and being with low incidence of side effects even at long term use. Monotherapy in mild-to-moderate hypertension controls blood pressure in 40 to 50% of these patients; when a low dose of thiazide diuretic is added, 60-70% of patients are controlled. The efficacy is similar to angiotensin-converting enzyme (ACE) inhibitors, diuretics, calcium antagonists and beta-blocking agents. AT(1) receptor blockers are specially indicated in patients with hypertension who are being treated with ACE inhibitors and developed side effects such as, cough or angioedema. The final position in the antihypertensive therapy in this special population and other clinical situations, such as left ventricular hypertrophy, heart failure, diabetes mellitus and renal disease, has to be determined in large prospective clinical trials, some of which are now being conducted and seem promising.

Angiotensin Receptor Antagonists↗
PubMed2002

Update on the use of calcium antagonists on hypertension.

Calcium antagonists represent an important group of drugs for the treatment of hypertension; they are effective in the whole range of severity of the disease. Dihy- dropyridine derivatives are most frequently used, and can be used in association with other antihypertensive drugs; meanwhile phenylalkylamines and benzothiazepines are contraindicated in association with beta-blocker drugs. Calcium antagonists with slow starting effect and long duration of action are the choice for use in long-term antihypertensive treatment. This group of drugs is specially indicated in elderly patients, in those with diabetes mellitus and in patients with coronary heart disease. Phenylalkylamines and benzothiazepine derivatives are also used in patients with supraventricular arrhythmias. This group of agents is as safe as diuretics, angiotensin-converting enzyme-inhibitors and beta-blocking drugs in the long-term treatment of hypertension.

Calcium Channel Blockers↗
PubMed2002

Comparison of two nimodipine formulations in healthy volunteers.

The objective of this study was to assess the pharmacokientic parameters of regular nimodipine (Bayer), 30 mg, given every 6 h and nimodipine AP (nimodipine in micro particles with programmed action contained in tablets, developed by Biocontrolled-Leti Group Laboratories), 120 mg, given every 24 h. Subjects (19 healthy volunteers, five female; 14 male: age: 21 +/- 0.7 years) received one formulation over 5 days. Then, after a washout period of 7 days, the other formulation was given. The analyst was blinded to the relationship in formulation received. Antecubital blood samples were taken before the first tablet was taken and after 15, 45, 60 min and 2, 4, 6, 8, 12, 13, 18 and 24 h on day 1 and five of each formulation. Nimodipine blood levels were analysed by HPLC. At steady-state regular nimodipine reached a C-max of 10.208 +/- 0.317 ng/ml, at a t-max of 1 h; minimum concentration 6 h after dosage was 1.2929 +/- 0.411 ng/ml, half-life was estimated in 2.9 h. Meanwhile nimodipine AP 120 mg reach a C-max of 11.885 +/- 0.403 ng/ml; a t-max of 1 h with a minimum concentration 24 h after the last dose of 4.2387 +/- 0.353 ng/ml (P < 0.001). Apparent half-life was calculated in 17.8 h (P < 0.001). Area under the curve for the 24 h period was 143.76 ng/ml/min for regular nimodipine and 183.7 ng/ml/min for nimodipine AP 120 mg (P < 0.001), indicating better bioavailability. In conclusion nimodipine in AP formulation 120 mg produced similar peak plasma levels (C-max) than regular nimodipine, but with higher trough (C-min) values and stable plasma levels with one administration every 24 h. This formulation would be more suitable when nimodipine chronic therapy is indicated.

Adult↗
PubMed2002

111Indium labelled leukocyte scintigraphy in the detection of acute prostatitis.

Although prostatitis is a common problem the diagnosis is still controversial despite the availability of a wide variety of diagnostic tools. In fact, there is still no accurate method of localizing the infected tissue. The aims of the present study were to assess whether 111In labelled leukocytes (ILLs) accumulated in the infected tissue of acute prostatitis and if such uptake responded to treatment. We prospectively studied 10 adult male patients who had community acquired prostatitis and compared them with six male patients who had urinary tract infections but without prostatitis. An initial urinary culture and two blood cultures were carried out for each patient. All patients were followed up for 8 weeks after therapy was completed. Pre- and post-treatment scintigraphies were performed. Before treatment, all patients with prostatitis showed uptake of ILLs in the prostate area. After the patients had completed treatment with antibiotics, the scintigraphy results showed no uptake in the prostate area in 9/10 patients. The remaining patient showed a marked decrease in the uptake of ILLs. None of the six patients with urinary tract infection showed ILL uptake in the prostate region. It is suggested that ILLs could be useful for detecting acute prostatitis, especially in clinically ambiguous patients with urological infections. Furthermore, scintigraphy with 111In labelled leukocytes could help to determine the most appropriate course of therapy.

Acute Disease↗
PubMed2001

Decreased invasive capacity of quinolone-resistant Escherichia coli in patients with urinary tract infections.

Quinolone-resistant (QR) Escherichia coli may have lower invasive capacity than does quinolone-susceptible E. coli. To evaluate this, we prospectively collected data regarding all cases of E. coli invasive urinary tract infections (IUTI) in 669 adults admitted to the Infectious Diseases Unit of our hospital during a 3-year period, as well as 10,950 patients with cystitis or asymptomatic bacteriuria who presented to the outpatient clinic during a 1-year period. QR E. coli was isolated in 20% of patients with cystitis, compared with 8% of those with IUTI (P<.05). The proportion of E. coli isolates that were quinolone resistant was similar in patients with bacteremic and nonbacteremic IUTI. The factors of urinary manipulation and structural abnormalities were independently associated with the presence of quinolone resistance. Old age was the only variable independently associated with blood invasion. QR E. coli is less likely to produce invasive disease (pyelonephritis and prostatitis) than is quinolone-susceptible E. coli. However, once pyelonephritis or prostatitis have developed, there is no difference in the incidence of bacteremia.

4-Quinolones↗