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C Mora

Publications and source records attributed to C Mora.

At least 19 recordsLinked to original sources
PubMed2006

[Heparin-induced thrombocytopenia in hemodialysis. Case report and review of the literature].

Thrombocytopenia is a potential complication of heparin therapy. There are two forms of heparin-induced thrombocytopenia (HIT). Type-I HIT is characterized by a mild decrease in platelet count that occurs within the first 2-4 days after heparin initiation. The platelet count often returns to normal without stop heparin treatment. The mechanism of thrombocytopenia appears to be due to a direct effect of heparin on platelet activation. The second form (type-II) is an immune-mediated disorder characterized by severe thrombocytopenia, which may include both arterial and venous thrombosis. We present a case of type-II HIT occurred in a hemodialysis patient resulting in acute pulmonary embolism and peripheral venous thrombosis, and review the literature.

Algorithms↗
PubMed2005

Four-body problem and BEC-BCS crossover in a quasi-one-dimensional cold fermion gas.

The four-body problem for an interacting two-species Fermi gas is solved analytically in a confined quasi-one-dimensional geometry, where the two-body atom-atom scattering length a(aa) displays a confinement-induced resonance. We compute the dimer-dimer scattering length a(dd) and show that this quantity completely determines the many-body solution of the associated BEC-BCS crossover phenomenon in terms of bosonic dimers.

Journal Article↗
PubMed2005

Estimation of atrial fibrillatory wave from single-lead atrial fibrillation electrocardiograms using principal component analysis concepts.

A new method for the assessment of the atrial fibrillatory wave (AFW) from the ECG is presented. This methodology is suitable for signals registered from Holter systems, where the reduced number of leads is insufficient to exploit the spatial information of the ECG. The temporal dependence of the bio-electrical activity were exploited using principal component analysis. The main features of ventricular and atrial activity were extracted, and several basis signals for each subspace were determined. Hence, the estimated (AFW) are reconstructed exclusively from the basis signals that formed the atrial subspace. Its main advantage with respect to adaptive template subtraction techniques was its robustness to variations in the QRST morphology, which thus minimised QRST residua. The proposed approach was first validated using a database of simulated recordings with known atrial activity content. The estimated AFW was compared with the original AFW, obtaining correlation indices of 0.774 +/- 0.106. The suitability of this methodology for real recordings was also proven, though its application to a set of paroxysmal AF ECGs. In all cases, it was possible to detect the main frequency peak, which was between 4.6 Hz and 6.9 Hz for the patients under study.

Algorithms↗
PubMed2004

Atom-dimer scattering for confined ultracold fermion gases.

We solve the three-body problem of a quasi-one-dimensional ultracold Fermi gas with parabolic confinement length a (perpendicular) and 3D scattering length a. On the two-body level, there is a Feshbach-type resonance at a (perpendicular)/a approximately 1.46, and a dimer state for arbitrary a (perpendicular)/a. The three-body problem is shown to be universal, and described by the atom-dimer scattering length a(ad) and a range parameter b(ad). In the dimer limit a (perpendicular)/a>>1, we find a repulsive zero-range atom-dimer interaction. For a (perpendicular)/a<<-1, however, the potential has long range, with a(ad)>0 and b(ad)>>a(ad). There is no trimer state, and despite a(ad)=0 at a( perpendicular)/a approximately 2.6, there is no resonance enhancement of the interaction.

Journal Article↗
PubMed2004

Pancreatic islets from cyclin-dependent kinase 4/R24C (Cdk4) knockin mice have significantly increased beta cell mass and are physiologically functional, indicating that Cdk4 is a potential target for pancreatic beta cell mass regeneration in Type 1 diabetes.

AIMS/HYPOTHESIS: Cyclin-dependent kinase 4 (Cdk4) is crucial for beta cell development. A mutation in the gene encoding for Cdk4, Cdk4R24C, causes this kinase to be insensitive to INK4 cell cycle inhibitors and induces beta cell hyperplasia in Cdk4R24C knockin mice. We aimed to determine whether this Cdk4R24C mutation also affects proper islet function, and whether it promotes proliferation in human islets lentivirally transduced with Cdk4R24C cDNA. METHODS: Our study was conducted on wild-type and Cdk4R24C knockin mice. Pancreases were morphometrically analysed. Intraperitoneal glucose tolerance tests and intravenous insulin tolerance tests were performed on wild-type and Cdk4R24C mice. We also did in vitro islet perifusion studies and islet metabolic labelling analysis. Human islets were transduced with Cdk4R24C cDNA. RESULTS: Pancreatic islets from Cdk4R24C knockin mice exhibit a larger insulin-producing beta cell area and a higher insulin content than islets from wild-type littermates. Insulin secretion in response to glucose is faster and reaches a higher peak in Cdk4R24C mice without leading to hypoglycaemia. Conversion of pro-insulin into insulin and its intermediates is similar in Cdk4R24C and wild-type mice. Glucose utilisation and oxidation measured per islet were similar in both experimental groups. Insulin secretion was faster and enhanced in Cdk4R24C islets perifused with 16.7 mmol/l glucose, with slower decay kinetics when glucose returned to 2.8 mmol/l. Moreover, human islets expressing Cdk4R24C cDNA exhibited higher beta cell proliferation. CONCLUSIONS/INTERPRETATION: Despite their hyperplastic growth, Cdk4R24C insulin-producing islet cells behave like differentiated beta cells with regard to insulin production, insulin secretion in response to glucose, and islet glucose metabolism. Therefore Cdk4 could possibly be used to engineer a source of beta cell mass for islet transplantation.

Animals↗
PubMed2004

[Prevalence of atrial fibrillation and relationed factors in a population in the centre Madrid].

INTRODUCTION: Atrial fibrillation is the most common arrhythmia on clinical practice and an important risk factor for ictus. The aim of this study was to know the prevalence of this arrythmia in a central district of Madrid. MATERIAL AND METHODS: A retrospective study was done analysing medical records of 13,945 patients belonging to a primary care centre of Madrid. Time of study: recruitment of data from September 2000 to May 2001; analysis of data: from September 2001 to May 2002. RESULTS: We obtained a total of 425 atrial fibrillations, 348 non-valvular and 77 valvular. Global prevalence of atrial fibrillation in patients over 40 years in our area was 2.52%. (2.47% male, 2.55% female). Risk factors for atrial fibrillation more frequently found in non-valvular were high blood pressure (HBP), diabetes, ischaemic heart disease and left ventricular dysfunction. Among valvulars we found HBP, left atrial size over 45 mm and left ventricular dysfunction. CONCLUSIONS: Atrial fibrillation shows a prevalence and distribution in the studied area similar to that found in other European countries.

Atrial Fibrillation↗
PubMed2003

Cloning and expression of Blo t 1, a novel allergen from the dust mite Blomia tropicalis, homologous to cysteine proteases.

BACKGROUND: House dust mite allergens have been shown to be a very important stimulus in the causation of asthma and triggers for the exacerbation of symptoms. Therefore, characterization of mite-derived allergens at the molecular level is an important step for the development of effective diagnostic and therapeutic approaches, as well as for epidemiological studies. OBJECTIVE: To clone, express and characterize at the molecular level the cysteine protease from Blomia tropicalis (Bt). METHODS: A full-length cDNA encoding Blo t 1 was cloned from a Bt cDNA library using a PCR and RACE-based strategy. The cDNA was PCR-amplified, sequenced and subcloned into a prokaryotic expression vector. The allergenicity of the recombinant Blo t 1 was evaluated for IgE reactivity by Western blot. RESULTS: Blo t 1 cDNA encodes a 221 amino acids polypeptide with an estimated molecular weight of 25 kDa. The recombinant protein is 35% identical to other mite cysteine proteases. Recombinant Blo t 1 (rBlo t 1) bound IgE from 62% of Bt skin test-positive serum. Dermatophagoides pteronyssinus (Dp) skin test-positive sera did not react with rBlo t 1, indicating the possible presence of unique IgE epitopes on the rBlo t 1 molecule. A three-dimensional image of Blo t 1, constructed based on predicted analysis, showed conserved secondary and tertiary structure with other cysteine proteases. CONCLUSION: We report the cloning, expression and IgE reactivity of Blo t 1, a novel allergen from the domestic mite Blomia tropicalis (Bt), highly homologous to cysteine proteases. This putative cysteine protease, designated Blo t 1, may play a major role as an immunodominant allergen involved in dust mite-specific IgE-mediated hypersensitivity.

Allergens↗
PubMed2001

Androgen therapy for anemia in elderly uremic patients.

Androgens were the mainstay of treatment of renal anemia prior to the introduction of recombinant human erythropoietin. With the introduction of this recombinant hormone, the protocols of treatment of anemia were completely modified, and the use of androgens was relegated to the background. However, several authors have continued showing interest in the use of androgenic steroids for the treatment of anemia. This review examines several aspects of aging on androgenic hormones and hematopoiesis, the effects of androgen administration on hematological parameters, the side effects of these compounds and the future of this treatment for anemia in renal patients.

Aged↗
PubMed2001

Tropical spastic paraparesis.

Human T-cell lymphotropic virus type I (HTLV-I) is the cause of endemic tropical spastic paraparesis (TSP) or HTLV-I-associated myelopathy (HAM). Because TSP/HAM is not a fatal disease, the neuropathology of this disease, albeit relatively well understood, is based on the examination of just a few incidental cases. We summarise our experience with the neuropathology of tropical spastic paraparesis/HTLV-I associated myelopathy (TSP/HAM). We studied three cases of TSP/HAM from different parts of the world. We demonstrated peculiar lamellated structures, called "multilamellar bodies" (MLB). It is tempting to suggest that MLB may represent specific ultrastructural markers of TSP/HAM. The pathology of the anteriorand posterior horns was similar and comprised axonal degeneration, accompanied by extensive astrocytic gliosis. Lymphocytic infiltration, particularly observed as "cuffs" around blood vessels, was scattered among other cellular elements. Ultrastructurally, myelin sheaths were relatively well preserved, and some demyelinated but not remyelinated fibres were observed. Moreover, axons with abnormal accumulations of neurofilaments, suggestive of axonal degeneration, were detected. Several axons contained Hirano bodies. In many samples glial processes replaced most of the remaining neuropil.

Ganglia, Spinal↗
PubMed2000

Neonatal tumor necrosis factor alpha promotes diabetes in nonobese diabetic mice by CD154-independent antigen presentation to CD8(+) T cells.

Neonatal islet-specific expression of tumor necrosis factor (TNF)-alpha in nonobese diabetic mice promotes diabetes by provoking islet-infiltrating antigen-presenting cells to present islet peptides to autoreactive T cells. Here we show that TNF-alpha promotes autoaggression of both effector CD4(+) and CD8(+) T cells. Whereas CD8(+) T cells are critical for diabetes progression, CD4(+) T cells play a lesser role. TNF-alpha-mediated diabetes development was not dependent on CD154-CD40 signals or activated CD4(+) T cells. Instead, it appears that TNF-alpha can promote cross-presentation of islet antigen to CD8(+) T cells using a unique CD40-CD154-independent pathway. These data provide new insights into the mechanisms by which inflammatory stimuli can bypass CD154-CD40 immune regulatory signals and cause activation of autoreactive T cells.

Animals↗