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M Romero

Publications and source records attributed to M Romero.

At least 37 records · Page 2Linked to original sources
PubMed2004

[Study of in vitro activity of caspofungin on non-Candida albicans yeast strains determined by two methods: M27-A2 and EUCAST].

The in vitro activity of caspofungin against 147 non-Candida albicans yeasts isolated from blood culture was studied using two broth microdilution methods: M27-A2 and EUCAST. The minimum concentrations that produced a growth inhibition of > or = 50% and of 100% (MIC2 and MIC0, respectively) and a reduction in the number of viable colonies > or = 99% versus the initial inoculum (MFC) were determined for all strains. Caspofungin demonstrated good activity (MIC2 and MIC0 < or = 2 mg/l for 90% of the strains) against the species studied, including those that are normally resistant or have a high percentage of azole resistance (Candida krusei, Candida glabrata, Candida tropicalis). Nevertheless, the antifungal activity is lower (MFC < or = 2 mg/l in 73.47% of the strains with the M27-A2 method versus 62.59% with EUCAST), particularly for Candida guilliermondii and Candida parapsilosis. The two methods tested demonstrated good correlation for the MIC and lower correlation for the MFC. Essential agreement and concordance (+/- 2 log) between both methods for all strains tested were: 73.47% and 93.20% for MIC2; 74.8% and 91.84% for MIC0; and 57.1% and 74.15% for MFC, respectively. MICs determined by the EUCAST method are one- to three-fold dilutions lower, while the MFC are higher than those obtained by the M27-A2 method.

Antifungal Agents↗
PubMed2003

Synthesis, pharmacology and pharmacokinetics of 3-(4-aryl-piperazin-1-ylalkyl)-uracils as uroselective alpha1A-antagonists.

Predominance in the urethra and prostate of the alpha(1A)-adrenoceptor subtype, which is believed to be the receptor mediating noradrenaline induced smooth muscle contraction in these tissues, led to the preparation of alpha(1A)-selective antagonists to be tested as uroselective compounds for the treatment of benign prostatic hyperplasia. Thus, a number of selective alpha(1A)-adrenoceptor antagonists were synthesized and assayed in vitro for potency and selectivity. Dog pharmacokinetic parameters of 12 (RO700004) and its metabolite 40 (RO1104253) were established. The relative selectivity of intravenously administered 12, 40 and standard prazosin to inhibit hypogastric nerve stimulation-induced increases in intraurethral prostatic pressure versus phenylephrine-induced increases in diastolic blood pressure in anesthetized dogs was 76, 71 and 0.6, respectively.

Administration, Oral↗
PubMed2003

Comparative study of the efficacy of an induction dose of interferon-alpha2b with ribavirin compared with standard combined treatment in naive patients with chronic hepatitis C.

The efficacy and secondary effects of an induction dose of interferon-alpha2b (IFN-alpha2b) with ribavirin compared with standard combined treatment in naive patients with chronic hepatitis C infection were compared. A prospective study was undertaken between March 1998 and November 2001 in which 84 Spanish hospitals took part. Six hundred and fourteen naive patients (age range 18-65 years) diagnosed with chronic hepatitis C virus (HCV) infection and without cirrhosis or co-infection by other viruses, were included. Patients were divided into two groups. Group A (n = 304) received induction treatment with a daily dose of 5 MU of IFN-alpha2b for 4 weeks, followed by 5 MU three times a week with ribavirin (1000-1200 mg/day, according to weight) until completing 1 year of treatment. Group B (n = 310) received the standard dose of IFN-alpha2b of 3 MU three times per week for 48 weeks together with ribavirin (1000-1200 mg/day, according to weight). Both groups were completely comparable according to age, gender, body weight, transaminase levels, genotype, viral load and hepatic inflammatory activity (Knodell Index). No control group was included for ethical reasons. Pegylated interferon was not available at the time of the study. Serum baseline samples were collected for the determination of genotype. Samples were also collected at baseline, weeks 4, 12, 24, 48 and 72, in order to detect and quantify HCV-RNA. The efficacy of treatment was evaluated by means of sustained viral response (SVR) characterized by persistent negativity of HCV-RNA at the end of the follow-up period. At week 4, the response to treatment was greater in group A (49.6%) compared with group B (34.5%) (P = 0.0002), and was maintained until week 12 (64.1% compared with 55.8% respectively) (P = 0.03). These differences disappeared at week 24, when group A (69%) was compared with group B (65%) (NS). At week 48, the response rate for group A was 50.6% compared with group B 47.4% (NS), and at week 72, the SVR in group A was 46% compared with 40.3% for group B (NS). The global SVR was 43.1%. On analysing the response to treatment according to genotype and viral load, we found that the induction treatment was slightly superior in patients with genotype 1 and an elevated viral load (>2 x 10(6) copies/ml). They achieved a SVR in group A of 39.1% compared with 25.5% in group B (P < 0.05). However, this slight improvement obtained in group A, was achieved at the expense of a greater percentage of dropouts compared with group B (6.4% vs 2.2%, P < 0.01); a greater rate of side effects (58.5 vs 36.7%, P < 0.05) and also a greater percentage of neutropenia (3.1% vs 0.9%, P < 0.05). The induction treatment presented a better initial response, but this was not maintained at the end of treatment, and did not improve the results obtained with the standard treatment. Although the patients with genotype 1 and elevated viral load had a better response with the induction treatment, this was accompanied by a greater percentage of dropouts and secondary effects. It would be interesting to repeat this type of study in the future, using pegylated interferon.

Adolescent↗
PubMed2003

Shall-issue policy and criminal activity among applicants for permits to carry concealed firearms.

Permits to carry concealed firearms in public (CCW permits) remain controversial. A small scale natural experiment with shall-issue CCW permit policy in California, a may-issue state, is reported. During the mid-1990s, the chief of police of the Sacramento County town of Isleton issued permits to all county residents who applied and passed a standard background check. This program received national publicity. The incidence of subsequent criminal activity among 691 persons applying for CCW permits through Isleton's program in 1995 and that in a statewide sample of 965 CCW applicants from 1993-94 were compared. Subjects were followed up for three years from their application dates. The arrest rates for violent crime among Isleton and statewide applicants were 291 and 104 per 100 000 person-years, respectively (relative risk 2.8, 95% confidence interval 0.7 to 11.2, p = 0.18). This suggests that a shall-issue policy for CCW permits may result in higher rates of violent crime among permit holders, but the results do not reach statistical significance; larger studies are needed.

Adult↗
PubMed2003

New advances in the field of calcium channel antagonists: cardiovascular effects and structure-activity relationships.

In the last 15 years, calcium channel blockers have been widely used for treating cardiovascular diseases. These agents are a heterogeneous group of drugs with differing cardiovascular effects, and are effective in the treatment of angina and hypertension. These synthetic compounds bind separately with receptor sites located in or near the calcium channel, at molecular sites still to be fully identified. Verapamil, nifedipine and diltiazem are the most representative calcium channel blockers and used as prototypes for the design and development of new anticalcium molecules with potential efficacy and reduced toxic effects. There are three different types of voltage-operated calcium channels (VOCs): L-type, T-type and N-type, which are considered extra-cellular, but some anti-calcium agents as bepridil possess potential intracellular calcium activity. Many synthetic compounds containing heterocyclic ring in their structures have attracted considerable interest since current studies revealed their mechanisms and sites of action. This article reviews the new advances in the calcium channel antagonist group, showing new structures with longer-acting and higher vascular selectivity.

Angina Pectoris↗
PubMed2003

Evaluation of the polymerase chain reaction in the diagnosis of miliary tuberculosis in bone marrow smear.

OBJECTIVE: Miliary tuberculosis (MTB) is difficult to diagnose. When prompt diagnosis is necessary, the polymerase chain reaction (PCR) to detect mycobacterial DNA may be valuable. SETTING: Tuberculosis clinic in an academic tertiary-level hospital in Mexico. DESIGN: Bone marrow (BM) aspiration samples from 30 consecutive clinically suspected MTB patients and 58 non-tuberculosis hematologic patients were evaluated by in-house PCR using a fragment of the insertion sequence IS6110; results were compared with those obtained by acid-fast-stained smears, culture in Löwenstein-Jensen medium, histology, and serology. RESULTS: Tuberculosis diagnosis was confirmed in all MTB suspects, 28 by microscopy and culture in pulmonary or extra-pulmonary samples other than BM, and two by clinical and radiologic improvement after antituberculosis treatment. In fresh BM specimens, in-house PCR was positive in 21/30 (70%) suspects, contrasting with only one positive (3.3%) in staining and culture, and four with compatible histologic findings (13.3%). BM samples from the control group showed negative results in bacteriologic and histologic studies, except in nine who had positive PCR results. These nine control cases had malignant processes. CONCLUSION: PCR in aspirates of BM is a useful diagnostic assay in cases of MTB, mainly when bacteriological results are negative.

Adolescent↗
PubMed2003

Investigation of biological risk in mycobacteriology laboratories: a multicentre study.

SETTING: Microbiology laboratories constitute a special working environment that may pose a risk of infectious disease to persons in or near them. OBJECTIVE: To assess whether clinical mycobacteriology laboratories in Spanish hospitals comply with occupational health and safety guidelines, and if laboratory workers are protected against the risk of exposure to biological agents in the workplace. DESIGN: A transversal epidemiological study was carried out in 26 hospitals from October to December 2000 by means of a standardised survey questionnaire to evaluate the workers, workload, training and information and safety practices in mycobacteria laboratories. RESULTS: Less than half of employees receive periodic information on the health hazards involved in their work. More than a third of the workers in mycobacteriology laboratories stated that the laboratories lack effective air filtering systems and more than half stated that negative pressurisation was not maintained in the work area. Biosafety masks are used by little more than half of the workers. The most frequently used Biological Safety Cabinets are Class IIB. CONCLUSION: Our findings demonstrate that clinical microbiology laboratories in Spanish hospitals comply poorly with the prevention measures outlined in the applicable directives and regulations.

Adult↗
PubMed2002

Utilisation of IGCC slag and clay steriles in soft mud bricks (by pressing) for use in building bricks manufacturing.

The subject of this study is the application to the construction of soft mud bricks (also known as pressed bricks), both green and heat-treated bodies, built from raw materials from Santa Cruz de Mudela, Ciudad Real, and IGCC slag from the power central of Puertollano (Ciudad Real, Spain). For this purpose, industrial level tests have been performed: the production of these kind of bricks from mixes of waste from ores of construction clays and to significant fraction of different ratios and clay granulometries mixed with IGCC slag. The results of this experimentation suggests that not only can IGCC slag be applied to a ceramic process, but also its use gives several advantages, as water and energy savings, as well as improvements on the final properties of products.

Aluminum Silicates↗
PubMed2002

Diversity of Bacillus thuringiensis strains from Colombia with insecticidal activity against Spodoptera frugiperda (Lepidoptera:Noctuidae).

AIMS: To identify and characterize Bacillus thuringiensis strains highly toxic to Spodoptera frugiperda, and to explore the genetic diversity of such strains. METHODS AND RESULTS: The insecticidal activity of 1100 strains of B. thuringiensis from Colombian soil samples was assayed against first instar S. frugiperda larvae, and 32 active strains were found. After a second bioassay evaluation, the eight most potent strains were selected for further characterization, which included crystal protein profiles determined by polyacrylamide gel electrophoresis, plasmid profile, plasmid restriction patterns, cry gene composition, qualitative determination of beta-exotoxin production, random amplified polymorphic DNA, serotyping, and toxicity to S. frugiperda. All Colombian strains contained cry1Aa, cry1Ab, cry1Ac, cry1B, cry1C and cry1D genes. However, PCR profiles of the Colombian strains suggested the presence of variants of the cry1 genes. Serotyping indicated that these strains belong to the kurstaki, thuringiensis, canadiensis and indiana subspecies. Interestingly, three strains belonging to different serotypes and subspecies were found in the same soil sample, and toxicity ranged between 11 and 976 ng cm(-2) of diet. CONCLUSIONS: It has been shown that B. thuringiensis strains belonging to different serotypes and displaying variable potency to S. frugiperda larvae can be found in the same soil sample. SIGNIFICANCE AND IMPACT OF THE STUDY: The results obtained indicate that some of the B. thuringiensis strains studied could be of interest for further development for S. frugiperda control programmes.

Animals↗
PubMed2001

The etiology of maternal mortality in developing countries: what do verbal autopsies tell us?

OBJECTIVE: To reassess the practical value of verbal autopsy data, which, in the absence of more definitive information, have been used to describe the causes of maternal mortality and to identify priorities in programmes intended to save women's lives in developing countries. METHODS: We reanalysed verbal autopsy data from a study of 145 maternal deaths that occurred in Guerrero, Querétaro and San Luis Potosí, Mexico, in 1995, taking into account other causes of death and the WHO classification system. The results were also compared with information given on imperfect death certificates. FINDINGS: The reclassification showed wide variations in the attribution of maternal deaths to single specific medical causes. CONCLUSION: The verbal autopsy methodology has inherent limitations as a means of obtaining histories of medical events. At best it may reconfirm the knowledge that mortality among poor women with little access to medical care is higher than that among wealthier women who have better access to such care.

Adult↗
PubMed2001

Long-term results of endovascular stent placement in the superior caval venous system.

PURPOSE: To present the long-term results in superior caval stenting for symptomatic obstruction. METHODS: Forty-nine stents were placed in 30 patients: 16 (53%) with malignant lesions, five (17%) with benign lesions and nine (30%) hemodialysis patients. Self-expandable stents were deployed on a first-line basis. Patients were followed clinically as well as by various imaging techniques and survival analysis was performed. RESULTS: Stent deployment was possible in all cases. Reocclusion was seen in 13 patients, of whom eight belonged to the hemodialysis group. Primary and secondary patency rates for malignant, benign and hemodialysis patients were respectively 74%, 50% and 22%, and 74%, 75% and 56% at 1 year. We had 7% complications and one death from iatrogenic superior vena cava injury. CONCLUSION: Primary stenting of superior caval obstruction is a first-choice treatment method achieving good mid-term patency. Patients with hemodialysis shunts must be closely monitored for early reintervention.

Adenocarcinoma↗
PubMed2001

Blood flow rate and energy charge in the isolated perfused canine liver.

Background. Liver viability depends on blood flow rate, which varies among isolated perfused livers used in different studies. We aimed to identify the minimal blood flow capable of keeping the energy charge compatible with liver viability. Materials and methods. Isolated canine livers were assigned to different groups (n = 4) with blood flow rates of 0.5 (Group I), 1.0 (Group II), and 1.5 ml/g/min (Group III). Blood gases, hematocrit, and glucose were measured over 180 min. Nucleotides, serum osmolarity, and electrolytes were also measured. Morphological changes were recorded at the end of each experiment. Results. Acid-base balance was better in livers from Group III. Electrolytes, osmolarity, hematocrit, and glucose showed no differences. Higher energy charges correlated with higher blood flow rates. On histopathology, there was evidence of more hydrostatic pressure-related changes in Group III, with no difference in necrosis or inflammatory-related alterations. Conclusions. (1) Energy charge correlates strongly with blood flow rate. (2) A rate of 1.5 ml/g/min allows for a better electrolyte, osmolarity, and acid-base balance. (3) Morphological analysis is not a sensitive predictor of organ viability as assessed by energetic potential. (4) The minimal blood flow rate required to attain an energy charge above 0.75 is 1.33 ml/g/min.

Acid-Base Equilibrium↗
PubMed2001

Characterisitcs of patients having thyroid surgery under regional anesthesia.

BACKGROUND: Recently local/regional anesthesia has been reintroduced as an alternative to general anesthesia for thyroidectomy. This study was undertaken to analyze characteristics and outcomes of patients who had thyroid surgery performed under regional anesthesia compared with those who had thyroidectomy under general anesthesia. STUDY DESIGN: One hundred seventy-five consecutive patients who underwent thyroid surgery under regional or general anesthesia during a 3-year period were analyzed. Fifty-eight operations were performed under regional anesthesia and 116 under general anesthesia. Patient characteristics analyzed included age, gender, obesity, anesthesia class, and tumor pathology. Postoperative complications, including nausea or vomiting, were compared. Additionally, operative times and length of stay in each group were compared. RESULTS: Patient characteristics including age, gender, tumor pathology, and anesthesia class were similar in both groups. But only 2% of patients treated under regional anesthesia were obese compared with 23% under general anesthesia. Although not significant, there was a trend toward decreased incidence of nausea and vomiting in the regional group. Other complications for the regional and general anesthesia groups were equal at 3%. Two patients required conversion to general anesthesia. Complications in the general anesthesia group included one episode of transient symptomatic hypocalcemia, two patients with transient vocal cord paralysis, and one episode of hematoma. Finally, there was a statistically significant increase in total operating room time and length of stay for the general anesthesia group. CONCLUSIONS: Regional anesthesia is a safe alternative to general anesthesia for patients undergoing thyroid surgery. Patients who cannot communicate verbally with the surgical team or who are obese may not be ideal candidates for regional anesthesia. The use of regional anesthesia results in a decreased length of stay and similar operative and operating room times.

Adolescent↗
PubMed2001

Intrahepatic expression of inducible nitric oxide synthase in acute liver allograft rejection: evidence of modulation by corticosteroids.

Nitric oxide (NO) has been proposed to have an important role in the immune response. Plasma nitrate levels increase during acute rejection and decrease after treatment with corticosteroids, but little is known about its potential cellular source. We studied inducible NO synthase (iNOS) expression in liver biopsy specimens of 12 patients with acute rejection compared with biopsy specimens from the same patients after treatment with high doses of intravenous corticosteroids. We also compared iNOS expression during acute rejection with a control group (9 patients without histological rejection). iNOS expression was assessed by immunohistochemistry. Intrahepatic iNOS expression was only observed in the cytoplasm of hepatocytes, which were diffusely distributed throughout hepatic lobules. iNOS expression could not be shown in portal tracts, inflammatory cells, or endothelial and sinusoidal lining cells. In patients with acute rejection, iNOS expression was significantly stronger than in the control group (2 +/- 0.7 v 0.6 +/- 0.7; P <.05). After treatment with corticosteroids, iNOS expression decreased significantly (2 +/- 0.7 v 1.3 +/- 0.9; P <.05). In conclusion, the findings of the present study show that during acute liver rejection, hepatocytes are the main cellular source for NO production and treatment with corticosteroids induces significant downregulation of intrahepatic iNOS expression.

Adrenal Cortex Hormones↗
PubMed2001

Multiple micronutrient supplementation increases the growth of Mexican infants.

BACKGROUND: The role of single micronutrient deficiencies in the etiology of growth retardation has recently gained attention. However, because multiple micronutrient deficiencies are common in children in developing countries, it is possible that more than one micronutrient may limit growth and, hence, the correction of a single deficiency may not be enough to improve growth substantially. OBJECTIVE: The objective was to evaluate the effect of multiple micronutrient supplementation on the growth of children aged 8-14 mo whose diets were poor in several micronutrients. DESIGN: Children were randomly assigned to 1 of 2 groups. One group received a multiple micronutrient supplement containing the recommended dietary allowance (RDA) or 1.5 times the RDA of vitamins A, D, E, K, C, B-1, B-6, B-12, riboflavin, niacin, biotin, folic acid, and pantothenic acid, and iron, zinc, iodine, copper, manganese, and selenium. The other group received a placebo. Supplements were administered 6 d/wk for an average of 12.2 mo. Body length was measured at baseline and monthly thereafter until the end of supplementation. RESULTS: Supplemented infants initially aged <12 mo had significantly greater length gains than did the placebo group, with a difference of 8.2 mm (length-for-age z score: 0.3) at the end of supplementation. In contrast, differences in length gains between the supplemented and placebo groups initially aged > or =12 mo were not significant. CONCLUSIONS: Micronutrient deficiencies limited the growth of the Mexican infants studied. Improving micronutrient intakes should be a component of interventions to promote growth in infants living in settings where micronutrient intakes are inadequate.

Age Factors↗