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R Reig

Publications and source records attributed to R Reig.

At least 19 recordsLinked to original sources
PubMed2001

SHV-1 beta-lactamase is mainly a chromosomally encoded species-specific enzyme in Klebsiella pneumoniae.

The nature of the SHV-1 beta-lactamase gene was analyzed in 97 epidemiologically unrelated Klebsiella pneumoniae strains isolated from clinical samples. beta-Lactamase bands that focused at a pI of 7.6 (SHV-1-type) in 74 strains, at a pI of 7.1 (LEN-1-type) in 13 strains, and at a pI of 5.4 (TEM-1-type) in 10 strains were detected by analytical isoelectric focusing (IEF). Among the 74 SHV-1-producing strains, 40 had, in addition to the pI 7.6 band, an additional band on IEF: 20 had a band with a pI of 7.1 and 20 had a band with a pI of 5.4. Most of the 74 SHV-1-producing strains (76.7%) carried plasmids. Transfer of beta-lactam resistance by conjugation was possible in only 9.3% of the strains tested. SHV-1 gene-specific PCR-restriction fragment length polymorphism (PCR-RFLP) analysis of the chromosomal DNA was positive for 93 of the 97 strains and negative for only 4 of the 10 samples with K. pneumoniae TEM-1 producers. In an attempt to approximate the location of the SHV gene locus by endonuclease restriction analysis, RFLP analysis with Southern blotting of chromosomal DNA with a labeled SHV-1 fragment as a probe was used to study the 97 strains. A trial with EcoRI showed at least one positive hybridization band for 96 strains; two bands were detected for 8 strains. The hybridization was negative for only one TEM-1 beta-lactamase-producing strain. DNA sequence analysis showed no differences in promoter regions or extra stop-triplet sequences; only point mutations determined different allelic variants. The novel SHV-type variants are designated SHV-32 and SHV-33. As a result of the RFLP and sequencing analyses, it can be postulated that the loci for SHV-1 and LEN-1 genes are arranged in tandem. Our results strongly support the hypothesis that the ancestor of the SHV-1 beta-lactamase originated from the K. pneumoniae chromosome.

Chromosomes, Bacterial↗
PubMed1995

Beta-lactamase activity in mycobacteria other than M. tuberculosis.

Beta-lactamase activity was studied in 142 non-tuberculosis mycobacterial strains. The distribution according to species was as follows: four M. avium, 14 M. chelonae, 10 M. fortuitum, 59 M. gordonae, 55 M. kansasii. The spectrum of hydrolysis of the beta-lactamases was screened using an acidimetric method and the characterization was performed by analytical isoelectric focusing.

Bacterial Proteins↗
PubMed1994

[Loss of antibiotic sensitivity of Pseudomonas aeruginosa strains during treatment].

BACKGROUND: Loss of sensitivity to betalactamic, quinolones and aminoglucoside antibiotics has been described during treatment of infections produced by strains of Pseudomonas aeruginosa. Sixteen nosocomial strains isolated over a year during which sensitivity to one or several antibiotics of the above mentioned groups had been lost during the course of treatment were studied. METHODS: The strains were identified by conventional techniques. Sensitivity to antibiotics was studied by determination of the minimum inhibitory concentration in solid medium, according to the guidelines of the National Committee for Clinical Laboratory Standards. Plasmidic beta-lactamases were identified by analytic isoelectric focusing. Hyperproduction of chromosomic lactamase was studied by a qualitative technique. The 0 antigens were studied against rabbit antisera. The pyocinetype was determined according to the Fyfe method. Plasmids were detected by alkaline lysis extraction and electrophoresis in agarose gel. RESULTS: The 16 strains in which changes in sensitivity were observed during the course of treatment represent 4.47% of all P. aeruginosa isolates during one year. Loss of sensitivity to betalactamic antibiotics was observed in 10 strains, in one to aminoglucosides, in two to ciprofloxacin, simultaneously to aminoglucosides and ciprofloxacin in one and to betalactamic and ciprofloxacin in another two. Six of the 13 patients (46%) required a change in antibiotic treatment. CONCLUSIONS: The convenience of following the sensitivity of the strains of Pseudomonas aeruginosa isolated in a patients is suggested to thereby avoid therapeutic failure and the potential danger of clonal dissemination of the strains which have lost sensitivity.

Adult↗
PubMed1993

Characterization of penicillinase-producing strains of Neisseria gonorrhoeae.

Twenty-three penicillinase-producing strains of Neisseria gonorrhoeae were characterized. All strains showed hybridization with a TEM-1 probe and production of a TEM-1 type beta-lactamase (pI 5.4) on isoelectric focusing. Eight strains also showed a beta-lactamase band of pI 5.5. The penicillin MICs for the strains producing only TEM-1 were in the range 4-16 micrograms/ml; MICs of the strains with the additional pI 5.5 band were > or = 128 micrograms/ml for seven strains and 4 micrograms/ml for an arginine-hypoxanthine dependent strain. The association of the high MICs with the presence of the pI 5.5 band was statistically significant. The pI 5.5 band could represent a new beta-lactamase type or a TEM-1 mutant.

Isoelectric Point↗
PubMed1993

A survey of beta-lactamases from 618 isolates of Klebsiella spp.

beta-Lactamases from 618 isolates of Klebsiella spp. (487 Klebsiella pneumoniae and 131 Klebsiella oxytoca) were identified by analytical isoelectric focusing. The strains were consecutive isolates from 618 different patients in five hospital centres between 1980 and 1984. Most of the chromosomal beta-lactamases from the K. pneumoniae isolates had a pI of 7.1, and most of the K. oxytoca isolates had chromosomal beta-lactamases of pIs 7.8, 5.3 and 5.5. Plasmid-mediated beta-lactamases were produced by 91.8% of K. pneumoniae isolates and 9.9% of K. oxytoca isolates. The beta-lactamase types identified most frequently were SHV-1 in the former species, and TEM-1 in the latter species. Of the K. pneumoniae isolates, 101 produced both of these plasmid-mediated beta-lactamases, while one strain produced an extended-spectrum SHV-like beta-lactamase. Of the 131 K. oxytoca isolates, 20 were hyper-producers of chromosomal beta-lactamase. The susceptibility of this genus to beta-lactam antibiotics is controlled almost exclusively by beta-lactamases, the production of which may differ from one strain to another; thus the empirical therapeutic use of beta-lactam antibiotics is not recommended for this genus.

Chromosomes, Bacterial↗
PubMed1993

In vitro antimicrobial production of beta-lactamases, aminoglycoside-modifying enzymes, and chloramphenicol acetyltransferase by and susceptibility of clinical isolates of Acinetobacter baumannii.

Antimicrobial susceptibility testing was performed on 54 epidemiologically unrelated clinical isolates of Acinetobacter baumannii by using a standard agar dilution technique. On the basis of the in vitro activities, imipenem and doxycycline were the most active agents, whereas amikacin, isepamicin, and the new fluorquinolones ciprofloxacin and ofloxacin presented moderate activity. Cephalosporinase activity was found in 98% of the strains, whereas lactamases of TEM type 1 and one with a pI of 7 to 7.5 were present in 16 and 11% of the strains, respectively. Resistance to aminoglycosides was explained by the production of the three classes of aminoglycoside-modifying enzymes, with predominance of aminoglycoside-3'-phosphotransferase VI in 28% of the strains.

Acinetobacter↗
PubMed1992

Clinical and pathological findings in fatal plant oxalosis. A review.

Poisoning by ingestion of oxalate-containing plants, such as raw rhubarb, is infrequent, and such deaths are rare. We present a review of the most important clinical and pathological aspects of oxalate poisoning and recommend that the public be educated about the dangers of eating unknown plants with potentially adverse effects.

Animals↗
PubMed1992

[The radiological findings in poisonings by metals].

We present four cases of heavy metal poisoning (mercury, lead, bismuth and arsenic) in which plain chest and/or abdominal assisted in the differential diagnosis of the clinical picture manifested upon admission at our Emergency Department. The patients suffering from mercury, lead, and bismuth poisoning recovered some weeks after treatment was started. However, the patient with arsenic trioxide poisoning developed cardio-circulatory collapse leading to death three days after admission.

Adult↗
PubMed1991

[Characterization of Haemophilus influenzae's resistance to ampicillin].

BACKGROUND: The resistance of Haemophilus influenzae to ampicillin is nearly always dependent on plasmid-mediated betalactamase production. The betalactamase type most frequently identified was TEM-1; type ROB has occasionally been identified. The presence of plasmid-mediated betalactamase has been studied in H. influenzae strains moderately susceptible or resistant to ampicillin. METHODS: The test used in the detection of the presence of betalactamase was nitrocefin hydrolysis; the enzyme type was identified by analytic isoelectric focusing; the codifying gene of this betalactamase was identified by hybridisation with a TEM-1 probe labeled with digoxigenine. Strains studied were 110, obtained during the period 1987 to 1989 and isolated from four Hospitals of the Vallés area of Barcelona. RESULTS: Enzyme production was detected in 105 of 110 strains studied; TEM-1 type betalactamase was identified in 108 and positive hybridisation was obtained in these strains with the TEM-1 probe. CONCLUSIONS: Nitrocefin hydrolysis is a reliable test for the detection of betalactamase production, although it may be unable to detect it (falses negatives) when the production is low. The only betalactamase type identified was TEM-1. The frequency of the strains with non-enzymatic resistance was 1.8%.

Adult↗
PubMed1990

Fatal poisoning by Rumex crispus (curled dock): pathological findings and application of scanning electron microscopy.

A case of fatal poisoning due to ingestion of the plant Rumex crispus (curled dock) is described. The patient, a 53-year-old male, presented with gastrointestinal symptoms, severe hypocalcemia, metabolic acidosis and acute hepatic insufficiency. Despite therapeutic measures, the patient died 72 h after ingestion of the plant material. Noteworthy among the pathological findings were centrolobular hepatic necrosis and birefringent crystals in the liver and kidneys that were identified by histochemical techniques and scanning electron microscopy. These observations are compared with other reports in the medical literature, with an emphasis on the risk involved in the use of these plants for culinary or medicinal purposes.

Edema↗
PubMed1989

[Failure of a cyclophosphamide-dexamethasone combination in paraquat poisoning].

A 37-year-old female deliberately ingested a 20% solution of paraquat in water. One hour later gastric lavage was carried out and bentonite was administered. Five hours later cyclophosphamide (5 mg/kg/day) and dexamethasone (24 mg/day) were started and a continuous intestinal lavage was carried out; four hours later, hemodialysis was begun. After 36 hours, features of renal and respiratory failure developed, with a rapid progress to respiratory distress. The patient died 94 hours after the ingestion of the poison. Despite early therapy with dexamethasone and cyclophosphamide, this patient's evolution does not support the presumed effectiveness of this drug association for paraquat poisoning.

Adult↗