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Biomedical subjects

Marta Pérez

Publications and source records attributed to Marta Pérez.

11 recordsLinked to original sources
PubMed2006

A multivariate index based on the seagrass Posidonia oceanica (POMI) to assess ecological status of coastal waters under the water framework directive (WFD).

We propose here a multivariate index based on structural and functional attributes of the Posidonia oceanica ecosystem (Posidonia oceanica multivariate index: POMI) to assess the ecological status of coastal waters following WFD requirements. POMI is based on the combination, through principal component analysis, of physiological, morphological, structural and community level seagrass descriptors (or metrics), univocally related to environmental quality. Scores on the first axis are normalised to a 0-1 scale (EQR) using reference and worst sites. The index was tested by sampling 22 seagrass beds in the Catalan coast (ca. 500 km, NW Mediterranean). The results show a clustering of variables on both sides of the first axis of the PCA, indicating a common relation of all metrics with ecological status. Moreover, the values (EQR) obtained reflect human pressure levels. The proposed index allows a practical and relatively simple assessment of the ecological status of coastal waters, and contains a considerable amount of ecological information, which can be useful for managing purposes.

Alismatales↗
PubMed2006

[Treatment of severe chronic constipation through the antegrade continent enema procedure].

The antegrade continent enema procedure was first described in 1990 by Malone for the treatment of severe fecal neurogenic incontinence in children. Since then, this technique has been successfully carried out in adults, as well as in patients with refractory constipation. The procedure provides a continent and catheterizable channel, generally an appendicostomy, through which antegrade washouts are given to produce colonic emptying. We describe the case of a 23-year-old man with severe constipation and overflow fecal incontinence who underwent an appendicostomy. There were no immediate postoperative complications and saline washouts were started on the fourth day. Since then, the patient has had a bowel movement between 1 and 3 hours after each washout, has recovered continence, and no longer wears an absorbent pad.

Adult↗
PubMed2005

Anti-cyclic citrullinated peptide autoantibodies in IgM rheumatoid factor-positive patients.

BACKGROUND: Antibodies to citrullinated proteins have been described in patients with RA and these appear to be the most specific markers of the disease. The objective of this study was to analyse the improvement in diagnostic accuracy of anti-cyclic citrullinated peptide autoantibodies and IgA rheumatoid factor in patients with clinical suspicion of RA and who were IgM rheumatoid factor-positive. Anti-CCP antibodies were measured with three different second-generation enzyme immunoassays. METHODS: We chose 133 serum samples with IgM RF levels greater than 20 IU/mL sent to our Laboratory from Specialized Care Units. Subsequently, patients were classified according to their clinical records. Eighty-seven had rheumatoid arthritis and 46 had other diseases. In all samples anti-CCP and IgA RF were measured by the corresponding ELISAs. RESULTS: Comparison of the three anti-CCP second-generation ELISAs revealed differences between them. Likewise, clinical performances in terms of sensitivity, specificity, and positive and negative likelihood ratios were different. In patients with IgM RF higher than 20 IU/mL, anti-CCP antibodies increased the clinical efficiency of IgM RF and offered better performance as compared with IgA RF. CONCLUSIONS: The use of anti-CCP antibodies affords good clinical efficiency and modifies the pre-test probability of the occurrence of RA in patients with IgM rheumatoid factor higher than 20 IU/mL.

Arthritis, Rheumatoid↗
PubMed2005

Laboratory screening of connective tissue diseases by a new automated ENA screening assay (EliA Symphony) in clinically defined patients.

BACKGROUND: The measurement of antinuclear antibodies (ANA) is used in the autoimmune laboratory for the screening of connective tissue diseases (CTD). ANA measurements are mainly performed by indirect immunofluorescence (IIF) on HEp-2 cells or by enzyme immunoassay (EIA). The objective of this study was to clinically evaluate an automated EIA for extractable nuclear antigens (ENA) which lacks anti-dsDNA for the screening of CTD. METHODS: The study involved a total of 170 serum samples, 54 from patients with CTD, 26 from patients with other autoimmune diseases, and 90 from patients with non-autoimmune diseases. For all sera, ANA detection was performed by IIF and by EliA Symphony (Pharmacia Diagnostics, Freiburg, Germany), an ENA screening which detects the following autoantibodies: SSA/Ro, SSB/La, U1RNP (70 kDa, A, C), Scl-70, JO-1, centromere B and Sm. Also, anti-dsDNA (EliA dsDNA, Pharmacia Diagnostics, Freiburg, Germany) was measured on all samples. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), efficiency, positive likelihood ratio (PLR), and negative likelihood ratio (NLR) were calculated. RESULTS: Diagnostic efficiency was similar for IIF (82.6%) and EliA Symphony (82.3%), as well as PLR (6.5 for IIF, and 7.3 for Eli Symphony), and NLR (0.35 for IIF, and 0.41 for EliA Symphony). The combined measurement of EliA Symphony and dsDNA increased sensitivity but not PLR. Area under receiver operator characteristic (ROC) curve was similar for IIF (0.847) and EliA Symphony (0.823). CONCLUSIONS: The results of the study demonstrate that EliA Symphony solely or combined with anti-dsDNA detection has an efficiency similar to HEp-2 cells IIF with a cut-off of 1:160 for the diagnosis of CTD.

Antibodies, Antinuclear↗
PubMed2005

[Surgical treatment of recurrent secondary hyperparathyroidism].

INTRODUCTION: Secondary renal hyperparathyroidism (SHPT) affects nearly all patients on regular hemodialysis. Between 5% and 10% will need surgery to control the disease. Despite a meticulous technique, the rate of recurrent/persistent hyperparathyroidism after surgery remains between 2% and 12%. PATIENTS AND METHOD: We reviewed the reoperations of 7 patients with recurrent or persistent SHPT from a series of 56 patients, 3 of which were referred from other units for treatment of recurrence. Subtotal parathyroidectomy (ST-PTX) was performed in 51 patients and total parathyroidectomy with autograft (TPTX-AT) was performed in the remaining 5 patients. RESULTS: Seven patients underwent reoperation for recurrent SHPT, 1 of them twice (8 reinterventions in 56 patients). In 2 patients only 3 parathyroid glands were removed at the first intervention and recurrence was due to the presence of a fourth gland. In 4 patients, ST-PTX was performed and recurrence was due to a remnant hyperplasic area in 1 and to a fifth gland in 3. Recurrence in the patient with a TPTX-AT was to due to cervical parathyromatosis. All the patients with recurrence had a positive preoperative Tc-MIBI scintigraphy and the computed tomography/magnetic resonance examination was highly useful for anatomical localization of the lesion and for planning the surgical approach.

Adult↗
PubMed2003

Evaluation of ontology development tools for bioinformatics.

Ontologies are being used nowadays in many areas, including bioinformatics. To assist users in developing and maintaining ontologies a number of tools have been developed. In this paper we compare four such tools, Protégé-2000, Chimaera, DAG-Edit and OilEd. As test ontologies we have used ontologies from the Gene Ontology Consortium. No system is preferred in all situations, but each system has its own strengths and weaknesses.

Computational Biology↗
PubMed2003

Benthic primary producers--a neglected environmental problem in Mediterranean maricultures?

Marine fish farming is increasing rapidly in the Mediterranean and in contrast to the Atlantic the coastal zone in the Mediterranean is characterized by clear waters with high transparency. This allows benthic primary producers such as the slow-growing seagrass Posidonia oceanica to grow at large depths at locations suitable for fish farming and generating a conflict between the conservation of these meadows and the growth of aquaculture operations in the Mediterranean. In this paper we review the current knowledge on environmental interactions between fish farming and benthic primary producers with particular focus on P. oceanica, as this seagrass is a key component along Mediterranean coasts. The recovery times of P. oceanica are very long, in the order of centuries, and losses of this species are thus considered to be irreversible at managerial time scales.

Aquaculture↗
PubMed2002

The relevance of carbohydrate hydrogen-bonding cooperativity effects: a cooperative 1,2-trans-diaxial diol and amido alcohol hydrogen-bonding array as an efficient carbohydrate-phosphate binding motif in nonpolar media.

Carbohydrates with suitably positioned intramolecularly hydrogen-bonded hydroxyl and amide groups have the potential to act as efficient bidentate phosphate binders by taking advantage of sigma- and/or ,sigma,pi-H-bonding cooperativity in nonpolar solvents. Donor-donor 1,2-trans-diaxial amido alcohol (1) and diol (3), in which one of the donor centres is cooperative, are very efficient carbohydrate-phosphate binding motifs. We have proven and quantified the key role of hydrogen-bonding centres indirectly involved in complexation, which serve to generate an intramolecular H-bond (six-membered cis H-bond) in 1 and 3. This motif enhances the donor nature of the H-bonding centres that are directly involved in complexation. A comparison of the thermodynamic parameters of the complexes formed between phosphate and a cooperative (1-Phos) or anti-cooperative (2-Phos) bidentate H-bonded motif of a carbohydrate has allowed us to quantify the energetic advantage of H-bonding cooperativity in CDCl3 and CDCl3/CCl4 (1:1.3) (Delta Delta G degrees=-2.2 and -2.0 kcal mol(-1), respectively). The solvent dependences of the entropy and enthalpy contributions to binding provide a valuable example of the delicate balance between entropy and enthalpy that can arise for a single process, providing effective cooperative binding in terms of Delta G degrees.

Carbohydrates↗
PubMedDate not supplied

[Commitment hierarchy of the Geneva declaration].

There is a revival at present in the use of the medical oath. A study of the text is necessary from the first year of study in medical school. The aim of this work was to know how medical students rank the commitments of the Geneva Declaration. One hundred seventy 1st-year students were evaluated. They were asked to enumerate the commitments in a hierarchy according to their perception of medical work. The greatest percentages of the principles for each position were obtained. The commitments placed first were respect to life (39.4%), consideration of patient health as first concern (23.5%), and non-discrimination (27.1%). Votes placed last in the ranking were related to honor and professional traditions (24.1%) and consideration of colleagues as brothers (28.8% and 44.7%). The difference among percentages was significant, mainly with regard the last commitment. Medical students located in the first places obligations with reference to ethical principles of physician-patient relationship, considering less relevant commitments with the profession and its members. It will be of interest to determine the reason for this dichotomy and to encourage reflection upon medical oaths, generating greater commitment.

Delivery of Health Care↗