PubMed Health⌕ Search

Biomedical subjects

M Díaz

Publications and source records attributed to M Díaz.

At least 19 recordsLinked to original sources
PubMed2006

Mixed biodiversity benefits of agri-environment schemes in five European countries.

Agri-environment schemes are an increasingly important tool for the maintenance and restoration of farmland biodiversity in Europe but their ecological effects are poorly known. Scheme design is partly based on non-ecological considerations and poses important restrictions on evaluation studies. We describe a robust approach to evaluate agri-environment schemes and use it to evaluate the biodiversity effects of agri-environment schemes in five European countries. We compared species density of vascular plants, birds, bees, grasshoppers and crickets, and spiders on 202 paired fields, one with an agri-environment scheme, the other conventionally managed. In all countries, agri-environment schemes had marginal to moderately positive effects on biodiversity. However, uncommon species benefited in only two of five countries and species listed in Red Data Books rarely benefited from agri-environment schemes. Scheme objectives may need to differentiate between biodiversity of common species that can be enhanced with relatively simple modifications in farming practices and diversity or abundance of endangered species which require more elaborate conservation measures.

Agriculture↗
PubMed2006

Rheological behavior and organoleptic effects of ovalbumin addition in yogurt mousse production.

Yogurt mousse is a novel, high added-value dairy product that has been well received by the market. This paper presents a study of the effect of the addition of ovalbumin to the product on its rheological and organoleptic qualities. The ovalbumin was previously separated from egg white with a high grade of purity using an ion exchange resin synthesized by the authors. Diverse rheological tests at different temperatures and corresponding sensorial assessments were conducted to compare samples without and with added ovalbumin. The obtained results confirm that the product is viscoelastic and combines the properties of foams and emulsions; the elastic component is greater than the viscous component. Moreover, at temperatures ranging from 5 to 15 degrees C, a usual interval of consumption, the product behaves rheologically in a similar way. Conversely, the addition of ovalbumin under the assayed conditions also makes the elastic character of the product increase at a given temperature. Finally, the sensorial assessment tests and determinations of stability and volume yield enabled us to verify that the addition of ovalbumin at an amount of 1.3% hardly alters the stability, resistance to shear stress, or the texture and improves the degree of foaming. Therefore, the product with additive is of good commercial quality.

Chromatography, Ion Exchange↗
PubMed2006

[Surgical management of cutaneous and musculoskeletal complications in fulminant sepsis].

INTRODUCTION: Surgical management of purpura fulminans is required as in the acute as in the sequelae period. A retrospective case review of these sequelae, procedures which have been performed in the different moments and the outcomes was undertaken. METHODS AND MATERIALS: We reviewed retrospectively 13 patients treated in our hospital from 1993 to 2003. 8 males and 5 females, with a median age of 2 years old (4 days-14 years) were managed. 70% were meningococcical. The most common areas were low extremities (92%), upper extremities (76%), lips (n=1), nose (n=1) and genitalia (n=1). Most of cases were bilateral (n=11) although two patients presented isolated affectation in one of the extremities. The procedures were classificated depending on the surgical moment. Clinical follow-up was attempted on all surgical patients; we evaluated the aesthetic, functional and psychosocial outcomes. RESULTS: One child died along the first 24 hours; 11 required early surgery and all of them required late interventions. 50% in the serie had necrosis over 15%. In Intensive Care Unit, it was necessary to do 6 fasciotomies (extirpating muscle in 2) and escharectomies and debridements in 8. Early amputations were made in 2 patients: both of them required ampliation in the following days. The cutaneous defects were covered with skin allografts and artificial dermis. During the sequelae period, 8 amputations were necessary (the four extremities in one case). Other procedures were coverage with autologous skin grafting (n=7), Zplasties, Wplasties (n=5), myocutaneous flaps (n=3), release of contractures (n=3) and osseus resection (n=5). There were skeletal growth disturbances which were managed with osteotomies (n=3), realineations(n=3), application of Ilizarov (n=2) and Hoffman (n=2) frames; Nowadays, 6 patients have a complete independent functionning with the use of orthotics (n=3) and prosthetics (n=3) CONCLUSION: The pediatric surgeon has an important role in management and prevention of complications in patients with purpura fuminans. Urgent actuation and close follow-up decreases the morbidity; furthermore, the early reparation of sequelae improves their adaptation in school, in the family and in the society despite the physical disability.

Acute Disease↗
PubMed2006

[Venous malformations. Diagnosis and treatment during the childhood].

INTRODUCTION: Congenital venous malformations are the most common slow-flow vascular abnormalities during childhood. Although they are usually present at birth, clinical evidence often appear during late childhood. This type of malformations do not disappear, and they grow progressively during years. PATIENTS AND METHODS: We present a retrospective study based on the medical records of 72 patients treated in our Department during the last 15 years. Patients' age at the diagnosis was 5 days to 26 years. Male-female relationship was 2:1. The most frequent locations were Upper and lower extremities, followed by head and neck. We do not include in this study those patients with mixed lesions involving CNS or abdomen. RESULTS: Main symptoms were: pain, 60%; thrombophlebitis, growing size of the extremities, dermis lesions, osseous dystrophy and chronic coagulopathy. Symptoms worsening was related to trauma, infections and hormonal changes. Clinical course was the clue for the diagnosis. Eco-doppler was useful to study the flow of the lesion. MRI was employed to determinate the limits of the lesion. We did not perform arteriography, and phlebography was used as a diagnostic and therapeutic tool. Plain X-rays showed phleboliths in most of patients and osseous changes in a group of six patients. Treatment was conservative and palliative using elastic stockings, pain therapy and thromboembolism prophylaxis. This was the only treatment in irresectable lesions and in those cases without functional abnormalities. Surgery and sclerotherapy were the main curative treatments. Sclerotherapy was employed in cases of intramuscular and in delimited lesions. Ethanol and Ethibloc (Sodic Amidotrozoate) were the sclerosant agents. We performed surgery in cases of cutaneous complications, localized muscular lesions and in cases of recurrences after sclerotherapy. Ablative surgery was followed by reconstructive attempts using cutaneous and dermal artificial grafts. CONCLUSIONS: Congenital venous malformations must be diagnosed and treated during childhood. Conservative and resective treatments are useful in different cases. Accurate diagnosis and treatment improve long term results.

Adolescent↗
PubMed2005

Upper limits on a stochastic background of gravitational waves.

The Laser Interferometer Gravitational-Wave Observatory has performed a third science run with much improved sensitivities of all three interferometers. We present an analysis of approximately 200 hours of data acquired during this run, used to search for a stochastic background of gravitational radiation. We place upper bounds on the energy density stored as gravitational radiation for three different spectral power laws. For the flat spectrum, our limit of omega0 < 8.4 x 10(-4) in the 69-156 Hz band is approximately 10(5) times lower than the previous result in this frequency range.

Journal Article↗
PubMed2005

Limits on gravitational-wave emission from selected pulsars using LIGO data.

We place direct upper limits on the amplitude of gravitational waves from 28 isolated radio pulsars by a coherent multidetector analysis of the data collected during the second science run of the LIGO interferometric detectors. These are the first direct upper limits for 26 of the 28 pulsars. We use coordinated radio observations for the first time to build radio-guided phase templates for the expected gravitational-wave signals. The unprecedented sensitivity of the detectors allows us to set strain upper limits as low as a few times 10(-24). These strain limits translate into limits on the equatorial ellipticities of the pulsars, which are smaller than 10(-5) for the four closest pulsars.

Journal Article↗
PubMed2005

[Advantages and characteristics of the laparoscopic approach in the elderly].

Both the age of the population and anesthetic and surgical techniques are advancing. Currently, 40% of surgical activity is performed in patients older than 65 years, who present a higher surgical risk than younger patients. The aim of treatment in the elderly is to provide the best possible quality of life, even though this represents a surgical challenge because of associated comorbidity and reduced cardiopulmonary reserve. From the moment at which laparotomy becomes an increased stress in the elderly, laparoscopic surgery can be particularly advantageous in this population. Therefore, minimally invasive surgery may have a greater impact in these individuals than in younger patients in reducing postoperative pain, cardiorespiratory complications, hospital stay, and recovery time before resuming physical activity. The recent advances in anesthesia, together with improved patient selection and perioperative cardiac care, and the general adoption of minimally invasive access have enabled more complex gastrointestinal procedures to be performed in the elderly. The factors that could influence the development of this type of approach in the elderly, as well as the precautions that should be taken, should be further analyzed.

Aged↗
PubMed2004

Bovine plasma protein fractionation by ion exchange chromatography.

An ion exchange chromatography process was developed to separate the main protein fractions of bovine blood plasma using a composite material, Q-HyperD resin, and a gel material, DEAE-Sepharose. The experiments were carried out at semipreparative scale. It was necessary to establish analytical methods of electrophoresis and HPLC to identify the fractionated proteins. Results show that these materials are able to adequately fractionate different protein groups from the raw blood plasma. This method may be used to avoid chemical fractionation using agents such as ethanol or PEG and, thus, decrease protein denaturation of the different fractions to be used for research or pharmaceutical purposes. The Q-HyperD resin presents a better retention capacity for plasma protein than DEAE-Sepharose under the experimental conditions employed.

Animals↗
PubMed2004

Therapeutic immunization with an inactivated HIV-1 Immunogen plus antiretrovirals versus antiretroviral therapy alone in asymptomatic HIV-infected subjects.

To determine whether the addition of an inactivated-gp120-depleted HIV-1 Immunogen to antiretrovirals (ARTs) conferred a beneficial effect on delaying time to virologic failure relative to that obtained by ARTs alone, a phase II clinical trial was performed in 243 asymptomatic, ART naïve, HIV-1 seropositive adults. The Cox model showed that HIV-1 Immunogen treatment was associated with a 34% decrease in the risk of virologic failure (P = 0.056). When the analysis incorporated baseline HIV-RNA stratification the risk of virologic failure in the HIV-1 Immunogen Arm was significantly reduced a 37% compared to the IFA placebo Arm (P = 0.034). The data suggest that therapeutic immunization plus ARTs could influence virologic control.

AIDS Vaccines↗
PubMed2004

Streptomyces lividans and Brevibacterium lactofermentum as heterologous hosts for the production of X22 xylanase from Aspergillus nidulans.

The Aspergillus nidulans gene xlnA coding for the fungal xylanase X22 has been cloned and expressed in two heterologous bacterial hosts: Streptomyces lividans and Brevibacterium lactofermentum. Streptomyces strains yielded 10 units/ml of xylanase when the protein was produced with its own signal peptide, and 19 units/ml when its signal peptide was replaced by the one for xylanase Xys1 from Streptomyces halstedii. B. lactofermentum was also able to produce xylanase X22, affording 6 units/ml upon using either the Aspergillus xlnA signal peptide or Streptomyces xysA. These production values are higher than those previously reported for the heterologous expression of the A. nidulans xlnA gene in Saccharomyces cerevisiae (1 unit/ml). Moreover, the X22 enzyme produced by Streptomyces lividans showed oenological properties, indicating that this Streptomyces recombinant strain is a good candidate for the production of this enzyme at the industrial scale.

Aspergillus nidulans↗
PubMed2004

Public health surveillance and incidence of adulthood Guillain-Barré syndrome in Spain, 1998-1999: the view from a sentinel network of neurologists.

Temporal variation in Guillain-Barré syndrome (GBS) warrants monitoring in certain situations. This study sought to describe a public-health-based GBS surveillance service in Spain and conduct pilot surveillance in the period 1998-1999. Neurologists from 11 hospitals countrywide, serving a population of 3.9 million, reported all patients, ages 20 years or over, admitted to hospital with suspected GBS. Cases that did not belong to the designated hospital catchment area or failed to fulfill diagnostic criteria after follow- up were excluded. Reported monthly incidence was compared against predicted incidence obtained from retrospective data (1985-1997) using a reported method based on 97.5% percentile values. Alarm thresholds for 2000 onwards were obtained by applying the same method to the updated 1985-1999 series. During the 2-year period, 98 GBS cases were reported, yielding an overall age-adjusted incidence of 1.26 per 100 000 population, with a breakdown by sex of 1.83 for males and 0.76 for females. Monthly incidence remained below or was similar to the corresponding threshold limit value. Seasonality with highest incidence in winter was more pronounced in the elderly. Preceding events, mainly respiratory infections, were identified in 71% of patients. Pilot two-year GBS surveillance in Spain resulted neither in alarm nor in preventive measures. Adult GBS incidence in Spain might be monitored by a surveillance system set up at short notice when a possible threat is perceived. A monthly incidence of over 3 per 100 000 person-years in the population aged 20 years or older would exceed threshold values.

Adult↗
PubMed2004

Histochemical assay to detect class III ADH activity in situ in Arabidopsis seedlings.

Whole-mount detection methods are quick, inexpensive and offer the possibility of studying the temporal and spatial patterns of gene expression in a morphological context. These methods have been used widely to detect messenger RNAs and to measure enzymatic activity of reporter genes, such as beta-galactosidase or beta-glucuronidase. Taking advantage of the fact that NADH generated during the oxidation of formaldehyde by class III alcohol dehydrogenase can reduce the compound nitroblue tetrazolium to form a blue precipitate, we have developed a new method to detect class III alcohol dehydrogenase activity in situ in whole Arabidopsis plants. This reaction has been used earlier for in situ electrophoresis detection and for histochemical analysis in animal tissue sections. With a few modifications, it can be used in whole Arabidopsis plants or excised plant tissues to allow a rapid analysis of class III ADH activity during development or in response to elicitors. The method might be extended to other dehydrogenases by using specific substrates.

Aldehyde Oxidoreductases↗
PubMed2004

[The multifocal hepatic hemangioendothelioma. Is always a benign tumor?].

UNLABELLED: The hepatic multicentric haemangioma is defined by its extension, affecting all the mass of the liver. The high mortality associated with it is mostly related with the complications produced by its enormous size (haemodynamic, platelet trapping, spontaneous rupture and bleeding). There is a general belief that is a benign tumor with possibility of spontaneous regression and cure. AIM: Retrospective analysis of our recent cases of MHH with the purpose of: 1 degrees) To show the evolution and results. 2 degrees) To realize if the "benign character" of the tumor is real or if some cases may be considered as malignant tumors. MATERIAL AND METHODS: 10 cases of MHH treated in the last 10 years. In 9 the age of presentation was less than 6 months and one patient was diagnosed at 3 and half years. The diagnosis was confirmed by image techniques in 7 cases and by biopsy in 3. In 7 patients extrahepatic vascular lesions were associated prior to the treatment. Methylprednisolone was given to all the cases and alpha-2-interferon was administered to the patients that not responded to the steroids. Vincristine was added to 2 patients. In two cases the hepatic artery embolization was tried and one patient had a liver transplant. RESULTS: Four children had at least one episode of congestive cardiac insufficiency, two patients suffered a consumption coagulopathy (Kasabach Merrit syndrome), and one presented acute hepatic failure. In six children it has been complete regression of the tumor, one more is still under treatment and three died. The dead were produced by the malignant behavior of the tumor in one case (tumoral rupture of a MHH recurrence in the transplanted liver), and possibly in other (intracranial haemorrhage and hepatic failure in a liver transplantation candidate without demonstrated extrahepatic extension in the previous studies, but with multiorgan dissemination at autopsy. In both cases it was impossible to discover signs of histologic or biologic malignancy neither in the primitive lesion nor in the metastasis. CONCLUSIONS: 1a) The regression of the MHH, spontaneous or induced by the treatment is frequent. 2a) Some cases of MHH are aggressive and develop local recurrences and distant metastasis. 3a) The discrimination between MHH of "benign" or "malignant" behaviour is not possible. 4a) Despite of the unpredictable biological conduct of the tumor, the liver transplantation must be considered as an option in the symptomatic cases that not respond to the conventional treatment.

Child, Preschool↗