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A Correia

Publications and source records attributed to A Correia.

At least 19 recordsLinked to original sources
PubMed2006

In99, an In100-related integron, its occurrence and prevalence in clinical Pseudomonas aeruginosa strains from a central region of Portugal.

In99, a possible ancestor of In100, is a class 1 integron associated with carbenicillinase (blaPSE) and aminoglycoside resistance genes [aac(6')-Ib and aadA2]. In99 was present in 8 of 81 clinical isolates of Pseudomonas aeruginosa from unrelated patients collected in different years. The strains fell into two clonal groups and exhibited resistance to beta-lactams and aminoglycosides.

Drug Resistance, Bacterial↗
PubMed2005

Long-term performance and microbial dynamics of an up-flow fixed bed reactor established for the biodegradation of fluorobenzene.

An up-flow fixed bed reactor (UFBR) was established to investigate the biodegradation of fluorobenzene (FB) under a number of operating conditions, which included variation in the concentration of FB in the feed stream (up to 180 mg l(-1)) and temporary suspension of feeding. Degradation of FB was followed for a period of 8 months under a continuous flow regime. During the operation of the UFBR, FB was never detected in the reactor effluent, being biodegraded by the microbial biofilm or adsorbed to the granular activated carbon (GAC). Biodegradation of FB was observed from the beginning of the reactor operation, and overall, it accounted for 50% of the total amount fed to the bioreactor. High organic loads of FB (210-260 mg d(-1) dm(-3)) were found to affect the biological removal efficiency, possibly due to an inhibitory effect caused by the higher FB concentrations fed to the bioreactor (149-179 mg l(-1)). When FB feeding was suspended for 1 month, biodegradation continued, indicating that the adsorbed FB became bioavailable. Biofilm bacterial dynamics were followed throughout the UFBR operation by denaturing gradient gel electrophoresis and plate-counting techniques, showing that a quite stable community was found in the bioreactor, and this was mainly attributed to the high selective pressure exerted by the presence of FB.

Biofilms↗
PubMed2005

Morphology and phylogeny of Botryosphaeria dothidea causing fruit rot of olives.

The taxonomic position of the causal agent of fruit rot of olives was determined from fresh collections of the fungus from central Greece. In culture it formed two types of conidia, namely fusiform, hyaline, aseptate conidia typical of the genus Fusicoccum, and dark-walled, ovoid, ellipsoid or fusiform, 1-2 septate conidia that are not typically observed in Fusicoccum. A phylogenetic analysis based on ITS and EF1-alpha sequences placed the fungus within the same clade as Fusicoccum aesculi, which is the anamorph of Botryosphaeria dothidea, and the type of the genus Fusicoccum.

Ascomycota↗
PubMed2005

The relationship between the androgen receptor CAG repeat polymorphism length and the response to intermittent androgen suppression therapy for advanced prostate cancer.

OBJECTIVE: To determine whether the duration of the off-treatment interval in patients being treated with intermittent androgen deprivation therapy can be predicted by the length of the CAG trinucleotide repeat polymorphism in the androgen receptor. METHODS: This is a companion study to a prospective randomized trial, NCIC CTG PR-7, comparing intermittent to continuous androgen deprivation therapy in men with PSA progression after radiation therapy. The duration of the first off-treatment interval was established for 76 participants randomized to the intermittent therapy arm of the trial. Androgen receptor CAG repeat polymorphism lengths were determined for these 76 participants. Statistical analysis was completed to determine a relationship between CAG repeat length and the duration of the off-treatment interval. RESULTS: A significant correlation was not established (P = 0.424) between androgen receptor CAG repeat length and the duration of the first off-treatment interval. Categorical analysis of CAG repeat lengths using 18 and 22 as cutoff points did not find any significant difference in the mean duration of the off-treatment interval between categories (P = 0.672 and 0.774, respectively). CONCLUSION: No relationship was established between the duration of the first off-treatment interval and the CAG repeat length.

Aged↗
PubMed2004

Floc characterisation by analysis of laser beam attenuation.

The continuous growth in the demand of good quality water for different purposes makes the control of environmental pollution a matter for public and official concern. The monitoring of particles for quality control of water or wastewater treatment is becoming important and the need for the development of control devices is increasing. The purpose of this work was to develop a photosedimentation method for floc characterization combining gravitational settling with photoelectric measurements. Settling particles cross a light beam that illuminates a detection system. The attenuation of the beam is related to the projected area of the particles and so the particle size distribution can be determined. When a floc crosses the beam, the amount of light reaching the detector is reduced. Voltage/time signals are analyzed in order to produce the physical characteristics of flocs such as size and density. Different light sources and detection systems were tested in calibration tests and afterwards flocculated suspensions were used for experimental analysis. Floc characteristics could then be related to the experimental conditions of floc formation (mixing conditions and polymer concentration). With the experience acquired, a prototype was designed and implemented, being capable of operating in laboratory or field conditions.

Environmental Monitoring↗
PubMed2004

Central nervous system Aspergillus fumigatus infection after near drowning.

AIMS: To report the case of a 26 year old white man, who developed chronic meningitis and intracerebral granulomata 15 days after an episode of near drowning in a swamp. METHODS: Aspergillus fumigatus was isolated from cerebrospinal fluid cultures. RESULTS: The patient died 70 days after the symptoms were first noticed, and seven days after a subarachnoid haemorrhage. Aspergillus has never been reported before as a cause of intracranial infection after near drowning. CONCLUSIONS: Physicians must be aware of this possibility when confronted with such a situation, because there are now effective therapeutic options for systemic aspergillosis.

Adult↗
PubMed1999

[Pulmonary thromboembolism in a female with resistance to activated protein C].

Primary or acquired hypercoagulable states favour thrombotic events. The identification of prothrombotic states is of immediate practical usefulness in the orientation, prophylaxis and treatment of pulmonary embolism. Detection of individuals resistant to activated protein C. the most frequent laboratory anomaly in the study of patients with venous thromboembolism, offers a better approach for these patients as well as a better prophylaxis and orientation of their direct relatives concerning thromboembolic events. The authors describe the clinical case of a young woman, previously healthy, who developed serious pulmonary thromboembolism, the resolution of which was difficult and the evolution unusual. Later, a state of resistance to activated protein C (aPCr) was identified. Concerning the case described, the authors reflect on hypercoagulable situations, especially "aPCr" states.

Activated Protein C Resistance↗
PubMed1999

[Extra-adrenal pheochromocytoma simulating acute myocardial infarction].

The authors present the case of a 65 year-old female who was admitted to the emergency room with epigastric pain, headache, palpitations, nausea, vomiting and sweating. The laboratory tests performed showed elevation of CK and CK-MB and the ECG presented sinus tachycardia. T-wave inversion and prolonged QT interval. The echocardiogram was normal. The patient was admitted to the ICU and during the standard myocardial infarction treatment (including beta-blocker) a wide range of the arterial pressure (230/140 to 70/40 mm Hg) was registered. In view of these new data, the hypothesis of pheochromocytoma and catecholamine induced myocarditis was suggested and later confirmed by high levels of plasmatic and urinary catecholamines. The abdominal echography. CT and MRI showed a large retroperitonal and para-aortic mass. The administration of phenoxybenzamine (30 mg/day) led to the normalization of the ECG and arterial pressure and the respective clinical improvement. The anatomopathological exam, after surgical removal, confirmed our hypothesis. Sixteen months after the surgical procedure the patient is assymptomatic, with normal arterial pressure and normal levels of plasmatic and urinary catecholamines.

Aged↗
PubMed1998

Pulsed-field gel electrophoresis analysis of the genome of Rhodococcus fascians: genome size and linear and circular replicon composition in virulent and avirulent strains.

Total DNA of virulent and avirulent strains of Rhodococcus fascians was resolved by pulsed-field gel electrophoresis (PFGE) into a discrete number of fragments by digestion with the endonucleases AseI and DraI. Restriction endonucleases PacI, PmeI, and SwaI yielded no fragments upon digestion of R. fascians genome, and all the other tested endonucleases recognizing 6 bp released too many fragments. The genome size was 5.6 megabases for the type strain R. fascians DSM 20669, and 5.8 megabases for the virulent R. fascians D188 strain. However the genome size of R. fascians CECT 3001 (NRRL B15096) was 8.0 megabases. No linear chromosome in the megabase range was observed under pulse conditions in which Saccharomyces cerevisiae and Schizosaccharomyces pombe chromosomes were perfectly resolved, suggesting that the R. fascians chromosome is circular. A new linear plasmid pIRN640 of 640 kb was found in the avirulent R. fascians CECT 3001 that did not hybridize with a probe internal to the fas region of pFiD188 known to be involved in plant pathogenicity in the virulent strain R. fascians D188. Virulence was correlated in all strains tested with the presence of the fas region. The AseI and DraI bands corresponding to the extrachromosomal elements were identified providing the basis for a physical map of this organism.

DNA, Circular↗
PubMed1998

Characterization of the rrnB operon of the plant pathogen Rhodococcus fascians and targeted integrations of exogenous genes at rrn loci.

A 6.0-kb SalI DNA fragment containing an entire rRNA operon (rrnB) was cloned from a cosmid gene bank of the phytopathogenic strain Rhodococcus fascians D188. The nucleotide sequence of the 6-kb fragment was determined and had the organization 16S rRNA-spacer-23S rRNA-spacer-5S rRNA without tRNA-encoding genes in the spacer regions. The 5' and 3' ends of the mature 16S, 23S, and 5S rRNAs were determined by alignment with the rrn operons of Bacillus subtilis and other gram-positive bacteria. Four copies of the rrn operons were identified by hybridization with an rrnB probe in R. fascians type strain ATCC 12974 and in the virulent strain R. fascians D188. However, another isolate, CECT 3001 (= NRRL B15096), also classified as R. fascians, produced five rrn-hybridizing bands. An integrative vector containing a 2.5-kb DNA fragment internal to rrnB was constructed for targeted integration of exogenous genes at the rrn loci. Transformants carrying the exogenous chloramphenicol resistance gene (cmr) integrated in different rrn operons were obtained. These transformants had normal growth rates in complex medium and minimal medium and were fully stable for the integrated marker.

Base Sequence↗
PubMed1997

[A structural analysis of the entrance exams for specialist interns from 1994 to 1996].

In order to obtain specialist training in Portugal, doctors must pass a multiple-choice examination. The aim of this article is to present a structural and mathematical analysis of the examinations in the last three years. We based our work on the calculation of reliability coefficient of the examinations, and the difficulty and discrimination index of the questions and the examinations as a whole. A detailed analysis of the examinations, including that of each of the three hundred questions, will be published by the Department of Health Manpower in January, 1997.

Education, Medical↗
PubMed1996

Cloning and characterization of an IS-like element present in the genome of Brevibacterium lactofermentum ATCC 13869.

A repetitive DNA element of the Gram+ Brevibacterium lactofermentum (Bl), cloned by a modification of the subtractive hybridization method, contained a 1.4-kb IS-like element, IS13869, which included an open reading frame (ORF) inside a perfect 26-bp terminal inverted repeat (TIR). An 8-bp direct repeat (DR) was found outside each TIR. The ORF encoded a deduced protein of 436 amino acids (49 380 Da) with extensive similarity to other known transposases of insertion elements of Mycobacterium smegmatis (IS1096). Pseudomonas sp. (tpnA) and Corynebacterium glutamicum (IS31831). Distinct patterns were observed in different strains of Bl by hybridization with a probe internal to IS13869: four copies of IS13869 occurred in the wild type (wt) and R31 strains, but only three of them were observed in a recA derivative of the wt. Analysis by pulsed-field gel electrophoresis suggested that at least one copy of IS13869 had changed its position inside the chromosome during the lineage of a Bl derivative.

Bacterial Proteins↗
PubMed1994

Pulsed-field gel electrophoresis analysis of the genome of amino acid producing corynebacteria: chromosome sizes and diversity of restriction patterns.

A large number of species of corynebacteria are known to be amino acid producers, including members of the genera Corynebacterium and Brevibacterium. Pulsed-field gel electrophoresis (PFGE) of DNA fragments obtained by using endonucleases which recognize AT-rich hexanucleotide or octanucleotide sequences produces a discrete pattern of bands useful for fingerprinting and physical mapping of the chromosome. Using Pacl and Swal endonucleases the genome of Brevibacterium lactofermentum ATCC 13869 (genome size 3052 kb) was consistently cut into 26 and 20 bands, respectively, and the genome of Corynebacterium glutamicum ATCC 13032 (2987 kb) yielded 27 and 26 fragments, respectively. The pattern of restriction fragments was identical for related strains (B. lactofermentum ATCC 13869, B. lactofermentum BLO, B. lactofermentum R31) but different from the pattern of fragments of other soil isolates of the same species (B. lactofermentum DSM 20412) or from closely related organisms such as C. glutamicum; the different pattern of restriction fragments may be used to differentiate taxonomically related species. Brevibacterium linens showed a different behaviour, due to its high G+C content; its genome (3105 kb) was resolved into 8 or 15 fragments, respectively, by digestion with the hexanucleotide-recognizing endonucleases DraI and AseI. PFGE of DNA fragments obtained using these enzymes is a powerful technique for quick resolution of the corynebacteria genome into a small number of large fragments.

Chromosomes, Bacterial↗
PubMed1993

[Primary hyperaldosteronism. A report of 2 clinical cases].

We describe two clinical cases of primary hyperaldosteronism caused by adrenal adenoma (Conn's syndrome) with very different forms of clinical presentation. Some theoretical considerations about diagnosis and treatment of the disease are made.

Adenoma↗