PubMed Health⌕ Search

Biomedical subjects

Rosa Villanueva

Publications and source records attributed to Rosa Villanueva.

11 recordsLinked to original sources
PubMed2005

Evaluation of different methods for detecting methicillin (oxacillin) resistance in Staphylococcus aureus.

OBJECTIVES: To evaluate the performance of oxacillin, cefazolin, cefoxitin, cefotaxime and imipenem discs; Etest for oxacillin; microdilution; agar screening plates with 2 and 6 mg/L of oxacillin; and PBP2' agglutination for detection of methicillin-resistant Staphylococcus aureus (MRSA). METHODS: A total of 102 clinical S. aureus isolates, including 51 MRSA isolates, tested by PCR for the presence or absence of the mecA gene (gold standard method), isolated from different patients and at different times, were tested with: oxacillin (1 microg), cefazolin, cefoxitin, cefotaxime and imipenem (all 30 microg) discs; Etest for oxacillin; microdilution with oxacillin; agar screening tests (ORSAB medium) with 2 mg/L or 6 mg/L of oxacillin; and PBP2' agglutination with two different kits for detection of MRSA strains. RESULTS: The cefoxitin disc, ORSAB medium and PBP2' detection all showed 100% sensitivity. The cefoxitin, cefazolin and imipenem discs, Etest for oxacillin, microdilution and agar screening method with 6 mg/L at 24 h showed the highest specificity (100%), although variable degrees of sensitivity. The cefoxitin disc, which showed negative and positive predictive values of 100% and 98%, respectively was the best method for detecting MRSA isolates. CONCLUSIONS: In the absence of availability of molecular biology techniques, the cefoxitin disc was the best predictor of methicillin resistance in S. aureus from among the techniques tested.

Bacterial Proteins↗
PubMed2005

Cloning and functional analysis of the gene encoding the 33- to 36-kilodalton outer membrane protein associated with carbapenem resistance in Acinetobacter baumannii.

We investigated a multiresistant strain of Acinetobacter baumannii isolated in our hospital. Analysis of the N-terminal peptide sequence of the outer membrane proteins (OMPs) purified from the strain allowed us to clone and sequence the nucleotides of the gene encoding the 33- to 36-kDa OMP associated with carbapenem resistance in A. baumannii.

Acinetobacter↗
PubMed2004

Lack of correlation between phenotypic techniques and PCR-based genotypic methods for identification of Enterococcus spp.

A total of 123 genetically-unrelated strains of Enterococcus spp. strains (51 Enterococcus faecalis, 57 Enterococcus faecium, 10 Enterococcus gallinarum, and 5 Enterococcus casseliflavus) were phenotypically identified by biochemical profiles and by using an automated method. The strains were also analyzed by a PCR assay to assess the accuracy of the phenotypically-based methods for identification of Enterococcus spp. With this aim, a PCR assay using different cell targets, which allows simultaneous detection of glycopeptide-resistant genotypes as well as identification to the species level by means of different gene targets, was used as the gold standard method. All 51 strains of E. faecalis were correctly identified, whereas 48 of 57 strains (84.2%) of E. faecium, were correctly identified. All of the strains of E. gallinarum and 3 out of 5 strains of E. casseliflavus were also correctly identified. The overall results showed that it is possible to identify Enterococcus spp. at the molecular level in less than 30 hours, compared with the 48-96 hours required for the phenotypically-based methods. The excellent accuracy of the PCR assay in identifying these species, particularly E. faecium, must also be emphasized. These findings may have implications for the routine clinical identification of enterococci species.

Bacterial Typing Techniques↗
PubMed2004

High-level resistance to ceftazidime conferred by a novel enzyme, CTX-M-32, derived from CTX-M-1 through a single Asp240-Gly substitution.

A clinical strain of Escherichia coli isolated from pleural liquid with high levels of resistance to cefotaxime, ceftazidime, and aztreonam harbors a novel CTX-M gene (bla(CTX-M-32)) whose amino acid sequence differs from that of CTX-M-1 by a single Asp240-Gly substitution. Moreover, by site-directed mutagenesis we demonstrated that this replacement is a key event in ceftazidime hydrolysis

Amino Acid Sequence↗
PubMed2004

Risk factors for colonization and infection in a hospital outbreak caused by a strain of Klebsiella pneumoniae with reduced susceptibility to expanded-spectrum cephalosporins.

Between February 2001 and January 2002, an increase in the number of Klebsiella pneumoniae isolates with reduced susceptibility to expanded-spectrum cephalosporins (RSKp) was detected in the neonatal unit of the Juan Canalejo Hospital, and 21 patients were either colonized or infected by the bacterial isolates. The current "gold standard" method for typing K. pneumoniae isolates is pulsed-field gel electrophoresis. However, this technique is expensive and time-consuming. In a search for faster and accurate alternatives to this method, we investigated PCR-based fingerprinting techniques (enterobacterial repetitive intergenic consensus sequence PCR [ERIC-PCR], repetitive extragenic palindromic sequence-based PCR [REP-PCR], and RAPD [randomly amplified polymorphic DNA]) for their ability to characterize K. pneumoniae isolates. The causal agent of the nosocomial outbreak was characterized by these techniques and was found to be a single epidemic strain (RSKp). A multiple regression logistic model was developed to identify potential independent factors associated with colonization and/or infection by RSKp. Logistic regression analysis was applied to all significant variables (P < 0.05) in the univariate analysis, and it was revealed that intubation (odds ratio [OR], 27.0; 95% confidence interval [95%CI], 5.39 to 135.14) and prematurity (OR, 4.4; 95%CI, 0.89 to 21.89) were such independent factors. Moreover, oxime cephalosporins did not appear to be statistically significant. Overall, the results showed that PCR-based techniques are expeditious and useful methods for typing K. pneumoniae isolates. Of the techniques studied, ERIC-PCR showed the highest discriminatory index (D = 0.828), followed by RAPD (D = 0.826) and REP-PCR (D = 0.773)

Cephalosporins↗
PubMed2003

[Antifungal susceptibility of Candida spp. isolates from blood cultures in a five-year period (1997-2001)].

INTRODUCTION: This retrospective study investigates the incidence of candidemia and antifungal susceptibility of Candida spp. isolates from blood cultures performed in the period from January 1997 to December 2001. METHODS: Amphotericin B, fluconazole, itraconazole and flucytosine minimal inhibitory concentrations (MICs) were determined using the Sensititre YeastOne broth microdilution assay for the 53 isolates detected in the study period: C. parapsilosis (22), C. albicans (19), C. glabrata (5), C. krusei (3), C. tropicalis (2) and C. guilliermondii (2). RESULTS: The incidence of candidemia was 0.25 episodes per 1000 admissions in the period studied. C. parapsilosis was present in 41.5% of cases, followed by C. albicans (35.8%), C. glabrata (9.4%), C. krusei (5.5%), C. tropicalis (3.7%) and C. guilliermondii (3.7%). Isolation of C. parapsilosis was significantly associated with the neonatal and pediatric ICU. None of the isolates presented an amphotericin B MIC > 1 micro g/ml. All the C. krusei isolates were resistant to fluconazole. Itraconazole resistance and dose-dependent fluconazole susceptibility was found in 80% of C. glabrata isolates. Only one C. parapsilosis isolate was resistant to flucytosine. CONCLUSIONS: The incidence of candidemia in our hospital was low. C. parapsilosis was the most common species and was associated with neonatal and pediatric ICUs. Fluconazole and itraconazole resistance was only found among C. krusei and C. glabrata isolates, which accounted for 15% of the total Candida spp. isolated from blood cultures in our hospital.

Adult↗
PubMedDate not supplied

[Burnout syndrome among nursing staff at a hospital in Madrid].

BACKGROUND: The term "burnout" is related to a situation arising increasingly more often among the professionals performing their duties by way of a long-term, direct, people-to-people relationship, which includes all healthcare professionals. This study is aimed at determining the prevalence of the Burnout syndrome and of the three components involved therein (emotional exhaustion, impersonalization and lack of personal fulfillment) among the nursing staff at the "Hospital Clínico Universitario San Carlos" in Madrid and the relationship thereof to certain socio-demographic, job-related and institutional factors. METHODS: A cross-sectional study was conducted among the professionals assigned to the nursing staff at the above-mentioned hospital. The variables involved were gathered by means of a questionnaire prepared by those conducting this study. The Burnout syndrome was measured by means of the Maslach Burnout Inventory, in the validated Spanish version thereof. RESULTS: The nursing staff is more impersonalized (p=0.004) and less fulfilled (p=0.036) than the nursing assistant/technician group. When the results of the four scales by units were analyzed, burnout was found to be greater among the nursing staff assigned to oncology and emergency care units (p=0.001), the impersonalization in the emergency rooms (p=0.007), and Burnout is once again greater in the oncology and emergency units (p=0.000). Those professionals who answered that there was little recognition of their nursing care scored worst regarding Burnout and the three aspects thereof (p =0.000). The lower the degree of on-the-job satisfaction, the higher the scores on the four scales (p=0.000). CONCLUSIONS: The conclusion which may be drawn from this study is that the profile of a person affected by Burnout is that of a professional with on-the-job experience who nevertheless considers very little recognition to be given to their caregiving and a high degree of dissatisfaction with the way in which their workplaces are managed.

Adult↗