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Biomedical subjects

G Espinosa

Publications and source records attributed to G Espinosa.

At least 19 recordsLinked to original sources
PubMed2003

The 4G/4G genotype of the 4G/5G polymorphism of the type-1 plasminogen activator inhibitor (PAI-1) gene is a determinant of penetrating behaviour in patients with Crohn's disease.

BACKGROUND: Crohn's disease is a heterogeneous disorder with polygenic inheritance. AIM: To assess the effect of the 4G/5G polymorphism of the type-1 plasminogen activator inhibitor (PAI-1) gene, the major inhibitor of fibrinolysis, on Crohn's disease susceptibility and phenotype. METHODS: One hundred and fifty-seven patients with Crohn's disease and 350 controls were included prospectively. Medical records were reviewed to determine changes in the Crohn's disease phenotype. The 4G/5G polymorphism was assessed by polymerase chain reaction techniques. RESULTS: The frequencies of the 4G/4G, 4G/5G and 5G/5G genotypes were similar in patients with Crohn's disease and controls. The 4G/4G genotype (P < 0.0001; odds ratio, 4.84) and male sex (P = 0.009; odds ratio, 2.63) were independent risk factors for penetrating behaviour in Crohn's disease. Most Crohn's disease patients had a non-penetrating phenotype at diagnosis. The probability of development of a penetrating phenotype within 5 years of diagnosis was higher in patients with the 4G/4G genotype (72% vs. 19%, P < 0.0001). CONCLUSIONS: The 4G/4G genotype of the PAI-1 gene does not influence Crohn's disease susceptibility, but increases by five-fold the probability of penetrating behaviour. Most patients with the 4G/4G genotype have a non-penetrating phenotype at diagnosis, but develop a penetrating behaviour within 5 years. Genotyping the 4G/5G polymorphism may be useful for the identification of a sub-group of patients with aggressive Crohn's disease, who might benefit from specific therapy.

Adult↗
PubMed2003

A representative survey of indoor radon in the sixteen regions in Mexico City.

Mexico City, also called Federal District, covers an area of 1504 km(2), and has more than 8 million inhabitants. It is located more than 2200 m above sea level in a zone of high seismic activity, and founded on an ancient lake. At present it is one of the most crowded and contaminated cities in the world, with thermal inversions. Chemical contaminants and aerosol particles in the environmental air are high most of the year. Due to these geological, environmental and socioeconomic conditions, Federal District presents very peculiar characteristics, which are important for understanding the distribution and measurements of indoor radon concentration. In this work the results of 3 year (1998-2000) measurements of indoor radon levels in the Federal District are presented. For the detector distribution and measurements, the actual political administrative divisions of the Federal District, consisting of 16 very well defined zones, was used. Nuclear track detection methodology was selected for the measurement, with a passive device close-end-cup system with CR-39 (Lantrack) polycarbonate as the detection material, with one step chemical etching, following a very well established protocol developed at the Instituto de Física, UNAM. Calibration was carried out at the Oak Ridge National Laboratory, and verification at the Instituto de Física chamber. The results show that the arithmetical mean values of the indoor radon concentration for each region of the Federal District follow a non-homogenous distribution.

Air Pollution, Indoor↗
PubMed2003

Long term outcome of catastrophic antiphospholipid syndrome survivors.

BACKGROUND: Catastrophic antiphospholipid syndrome (APS) is defined as life threatening multiple organ thromboses developing simultaneously or over a short period. The survival rate of catastrophic APS is about 50%, but the long term outcome of patients who survive is unknown. OBJECTIVE: To determine the long term outcome of patients with catastrophic APS and provide further information on patients who survived. PATIENTS AND METHODS: The clinical characteristics and outcomes of 130 patients with catastrophic APS have been reported previously. Six new cases were recently added to this series. Based on these publications, the authors who reported patients who had survived were contacted. Each author was asked (a) what treatment they gave their patients after the catastrophic APS; (b) if their patients had any further thrombosis. RESULTS: 63/136 (46%) patients died at the initial event. Of the remaining 73 patients, information was available for 58 (79%). Thirty eight (66%) patients did not develop further APS related events during an average follow up of 67.2 months. Eleven (19%) patients developed further APS related events but were still alive. No patients developed further catastrophic APS. Nine (16%) patients died: due to multiple organ failure (three patients); myelofibrosis (one); pneumonia (one); and APS related events (four). CONCLUSION: Sixty six per cent of patients who survive an initial catastrophic APS event remained symptom free with anticoagulation during an average follow up of 67.2 months. Twenty six per cent of the survivors developed further APS related events and the mortality rate of these patients was about 25%.

Adolescent↗
PubMed2003

Analysis of patient flow in the emergency department and the effect of an extensive reorganisation.

OBJECTIVES: To evaluate the different internal factors influencing patient flow, effectiveness, and overcrowding in the emergency department (ED), as well as the effects of ED reorganisation on these indicators. METHODS: The study compared measurements at regular intervals of three hours of patient arrivals and patient flow between two comparable periods (from 10 February to 2 March) of 1999 and 2000. In between, a structural and staff reorganisation of ED was undertaken. The main reason for each patient remaining in ED was recorded and allocated to one of four groups: (1) factors related to ED itself; (2) factors related to ED-hospital interrelation; (3) factors related to hospital itself; and (4) factors related to neither ED nor hospital. The study measured the number of patients waiting to be seen and the waiting time to be seen as effectiveness markers, as well as the percentage of time that ED was overcrowded, as judged by numerical and functional criteria. RESULTS: Effectiveness of ED was closely related with some ED related and hospital related factors. After the reorganisation, patients who remained in ED because of hospital related or non-ED-non-hospital related factors decreased. ED reorganisation reduced the number of patients waiting to be seen from 5.8 to 2.5 (p<0.001) and waiting time from 87 to 24 minutes (p<0.001). Before the reorganisation, 31% and 48% of the time was considered to be overcrowded in numerical and functional terms respectively. After the reorganisation, these figures were reduced to 8% and 15% respectively (p<0.001 for both). CONCLUSIONS: ED effectiveness and overcrowding are not only determined by external pressure, but also by internal factors. Measurement of patient flow across ED has proved useful in detecting these factors and in being used to plan an ED reorganisation.

Analysis of Variance↗
PubMed2003

Adrenal involvement in the antiphospholipid syndrome.

Although Addison disease and hypoadrenalism are rare in patients with systemic lupus erythematosus (SLE), early reports of the association suggested the presence of antiphospholipid antibodies (aPL) in these patients. Data from literature reveal that adrenal failure was present in between 10 and 26% of patients with catastrophic APS and that one-third of patients presented with adrenal involvement during the course of catastrophic APS. Adrenal involvement may be the first clinical manifestation of this syndrome, whereas a few patients may have a history of Addison's disease in the past. The pathological mechanisms involved in the production of adrenal insufficiency in APS are still not clearly understood, but the hypercoagulable state in these patients supports the concept that adrenal haemorrhagic infarction may possibly be related to adrenal vein thrombosis. In the present article,we review the pathogenic mechanisms and main clinical, laboratory and treatment features of patients suffering adrenal involvement with aPL to support the idea that APS leads to the development of adrenal insufficiency.

Adrenal Insufficiency↗
PubMed2002

Myelodysplastic and myeloproliferative syndromes associated with giant cell arteritis and polymyalgia rheumatica: a coincidental coexistence or a causal relationship?

A variety of systemic autoimmune disorders have been reported in patients with myelodysplastic and myeloproliferative syndromes. A possible association with polymyalgia rheumatica and giant cell arteritis has also been recognised. We report another case of polymyalgia rheumatica and one of giant cell arteritis associated with a myelodysplastic syndrome and the two first cases of giant cell arteritis associated with essential thrombocytaemia and chronic myelomonocytic leukaemia, respectively. It seems that there is a relationship between these entities, but the nature of this association is still unknown.

Aged↗
PubMed2002

Neutron angular distribution in a plasma focus obtained using nuclear track detectors.

The dense plasma focus (DPF) is a coaxial plasma gun in which a high-density, high-temperature plasma is obtained in a focused column for a few nanoseconds. When the filling gas is deuterium, neutrons can be obtained from fusion reactions. These are partially due to a beam of deuterons which are accelerated against the background hot plasma by large electric fields originating from plasma instabilities. Due to a beam-target effect, the angular distribution of the neutron emission is anisotropic, peaked in the forward direction along the axis of the gun. The purpose of this work is to illustrate the use of CR-39 nuclear track detectors as a diagnostic tool in the determination of the time-integrated neutron angular distribution. For the case studied in this work, neutron emission is found to have a 70% contribution from isotropic radiation and a 30% contribution from anisotropic radiation.

Copper↗
PubMed2002

Measurements of alpha particle energy using nuclear tracks in solids methodology.

In this paper we present a method for the measurement of alpha particle energy using polycarbonate materials as nuclear track detectors (NTDs). This method is based on the interaction of the radiation with the solid-state materials, using the relationship between the energy deposited in the material by the ionising particle and the track developed after an established chemical process. The determination of the geometrical parameters of the formed track, such as major axis, minor axis and overall track length, permit determination of the energy of the alpha particle. The track analysis is performed automatically using a digital image system, and the data are processed in a PC with commercial software. In this experiment 148Gd, 238U, 230Th, 239Pu and 244Cm alpha particle emitters were used. The values for alpha particle energy resolution, the linear response to energy, the confidence in the results and the automatisation of the procedure make this method a promising analysis system.

Alpha Particles↗
PubMed2002

Nuclear tracks in CR-39 produced by carbon, oxygen, aluminium and titanium ions.

This work describes the response of CR-39 (allyl diglycol polycarbonate) to different ions (C, O, Al and Ti) produced by the Instituto de Fisica 3 MV 9SDH-2 Pelletron accelerator and backscattered from a thin Au film on a C support. The ion energies were chosen in series such that the ranges of the different ions in the detector were 2, 3, 4, 5, 6, 7 and 8 microm respectively for each series. Once exposed, the detectors were etched with a solution of 6.25 M KOH at 60 degrees C, and the reading was carried out using a digital image analysis system. An analysis of the measured track diameters of all the types of ions indicates that, for a given range, track kinetics are independent of type of ion, energy and stopping power.

Aluminum↗
PubMed2002

Analysis of the formed track in solid state materials using atomic force microscopy.

The track formation in solid state materials, from the theoretical point of view, is still under study. One way to understand the track formation mechanisms and radiation damage of the charged particles in some materials such as polymers, glasses and minerals, is to analyse the surface topography effects. In this work, the track formation analysis in polycarbonate material is presented using an atomic force microscope (AFM) to characterise the evolution of the track on the material surface and beyond a thin layer of the surface material. The AFM is very useful to obtain valuable information at the level of the atomic structure of the materials and of the nuclear tracks, due to its high resolution and very easy operation involving also a simple sample preparation. The results show the development of the formed track by means of induced surface effects after being exposed to ionising radiation and chemical etching.

Microscopy, Atomic Force↗
PubMed2002

The lung in the antiphospholipid syndrome.

Patients with antiphospholipid syndrome (APS) may develop a broad spectrum of pulmonary disease. Pulmonary thromboembolism and pulmonary hypertension are the most common complications, but microvascular pulmonary thrombosis, pulmonary capillaritis, and alveolar haemorrhage have also been reported. Clinicians should seriously consider these types of vascular injury when evaluating patients with APS who present with dyspnoea, fever, and infiltrates on chest radiography.

Antiphospholipid Syndrome↗
PubMed2002

Clinical significance of acquired activated protein C resistance in patients with systemic lupus erythematosus.

Antiphospholipid antibodies (aPL) may induce acquired activated protein C resistance (acquired APCR). The role of acquired APCR in patients with systemic lupus erythematosus (SLE) is not well known. To evaluate the prevalence of acquired APCR and its association with clinical manifestations we studied 103 consecutive SLE patients and 103 matched controls. APCR in the undiluted test and after dilution in factor V deficient plasma, factor V Leiden, protein C and S, lupus anticoagulant, and anti-cardiolipin, anti-beta2-glycoprotein I and anti-prothrombin antibodies were determined. Factor V Leiden was found in 4% in both patients and controls. The prevalence of acquired APCR was 22% for the undiluted assay and 17% in the diluted test. In SLE patients, acquired APCR was associated with aPL (39 vs 13% in undiluted assay, P = 0.007; and 33 vs 7% in the diluted test, P = 0.001). Arterial thromboses were found in 24% of patients with acquired APCR and in 6% of patients without (P = 0.04). However, no relationship was found with venous thrombosis. Acquired APCR was also associated with pregnancy losses: miscarriages in 70% of women with acquired APCR vs 32% in those without (P=0.03). Thus, in SLE patients acquired APCR seems to be associated with increased prevalence of arterial thrombosis and pregnancy losses.

Abortion, Spontaneous↗
PubMed2002

Lessons from the "Euro-Lupus Cohort".

The "Euro-Lupus Cohort" is composed by 1,000 patients with systemic lupus erythematosus (SLE) that have been followed prospectively since 1991. These patients have been gathered by a European consortium - the "Euro-Lupus Project Group". This consortium was originated as part of the network promoted by the "European Working Party on SLE", a working group created in 1990 in order to promote research in Europe on the different problems related to this disease. The "Euro-Lupus Cohort" provides an updated information on the SLE morbidity and mortality characteristics in the present decade as well as defines several clinical and immunological prognostic factors.

Adolescent↗
PubMed2001

[Liquid ecstasy poisoning: study of 22 cases].

BACKGROUND: To describe characteristics of acute poisoning with liquid ecstasy (gammahydroxybutyrate, GHB). PATIENTS AND METHOD: Epidemiological and clinical data of patients with acute GHB poisoning seen at emergency department (ED) along one year were collected. RESULTS: 22 patients were included. Typical profile corresponds to a young male, who consults on weekend, at night, complaining of a marked decreased level of consciousness. Patients refer coingestion of other drugs and typically regain consciousness spontaneously in a short time. CONCLUSION: The frequency of GHB poisoning has increased notably in our environment. GHB poisoning must be considered on the differential diagnostic of coma of unknown origin in young patients attended in ED.

Adolescent↗
PubMed2001

[Impact in the quality of health care and cost-effectiveness analysis of the reform of an emergency medicine service].

BACKGROUND: To determine the effects that the reform of an emergency department (ED) have on efficacy, health care quality and efficiency. MATERIAL AND METHOD: Reforms consisted of 50% and 34% increases in structural and human resources, respectively. Roles of each ED member were redetermined, new assistance pathways were implemented, and the relationship between ED and the remaining hospital departments was reassessed. As efficacy markers, we determined the number of patients waiting to be attended (Pesp), the waiting time of patients to receive medical assistance (T(esp)),and the total waiting time of patients staying in the ED (T(total)). As health-care quality markers, we determined the percentage of patients leaving ED without having been visited by a physician(IPNV), the percentage of patients who were visited again (IPR),and the percentage of mortality (IPF). We also quantified the number of visits to the ED. All these data were obtained daily over 3 weeks, before (February 1999) and after (February 2000)the reforms. Effectiveness was estimated from the ratio P(total)/T(esp)(E1) and P(total)/P(esp) (E2). Costs were recorded for both periods and a cost-effectiveness analysis was performed to study the efficiency. RESULTS: In 2000, the number of visits increased by +12% (CI 95%: 2% to 22%). Despite this increase, we observed an improvement of most efficacy and health-care quality markers after the ED reforms. E1 increased by 996% (CI 95%: 335% to 1,658%) and E2 increased by 186% (CI 95%: -23%to 395%). Cost-effectiveness analysis showed 70% (CI 95%: 33%to 107%) and 56% (CI 95%: 18% to 94%) increases regarding E1 and E2, respectively, after the reforms. CONCLUSIONS: Providing ED with the necessary resources leads to an objective improvement of its efficacy and health-care quality and, consequently, the service and quality perceived by users improve. Despite the total cost increase after the ED reforms, efficiency also improves.

Cost-Benefit Analysis↗
PubMed2001

Antiphospholipid antibodies and thrombophilic factors in giant cell arteritis.

OBJECTIVES: To evaluate the prevalence of thrombophilic risk factors known to induce intravascular clotting and to assess their relationship with ischemic manifestations in giant cell arteritis (GCA). METHODS: Eighty consecutive patients with established GCA were included: 36 with isolated temporal arteritis (TA), 14 with isolated polymyalgia rheumatica (PMR), and 30 with TA and PMR. Forty-four patients (67%) had ischemic phenomena due to GCA. Twelve patients (15%) had thrombotic events unrelated to GCA (6 strokes, 5 deep venous thrombosis, and 1 myocardial infarction). A control group of 100 age- and sex-matched individuals without autoimmune disease, bleeding disorders, thrombosis, or clinical picture of TA or PMR also was analyzed. All participants were tested for the antiphospholipid antibody (aPL) profile, protein C, protein S, antithrombin activity, factor V Leiden mutation, and prothrombin gene G20210A mutation. We also studied fibrinolysis parameters: plasminogen, tissue-type plasminogen activator (t-PA) antigen, t-PA activity, type-1 plasminogen activator inhibitor (PAI-1) antigen, PAI-1 activity, and the 4G/5G polymorphism of the promoter region of the PAI-1 gene. RESULTS: Eleven patients (18%) tested positive for lupus anticoagulant, 24 (30%) for anticardiolipin antibodies, 9 (11%) for anti-beta 2-glycoprotein I antibodies, and 29 (36%) for antiprothrombin antibodies. No relationship was found between these autoantibodies and ischemic manifestations. None of the patients had decreased protein C, protein S or antithrombin activity. Two patients and 2 controls were heterozygous for factor V Leiden, and only 1 patient and 2 controls were heterozygous for the prothrombin gene G20210A mutation. No statistically significant correlation was found between any thrombophilic factor and GCA-related or GCA-unrelated ischemic events. CONCLUSION: GCA patients have a high prevalence of aPL that is not related to ischemic manifestations. Moreover, GCA-related or GCA-unrelated ischemic manifestations do not appear to be due to congenital thrombophilic risk factors. Semin Arthritis Rheum 31:12-20.

Aged↗