Biomedical subjects

A Hidalgo

Publications and source records attributed to A Hidalgo.

At least 19 recordsLinked to original sources

PubMed2006

Hippocampal upregulation of the cyclooxygenase-2 gene following neonatal clomipramine treatment (a model of depression).

Although a putative role has been attributed to inflammation in the pathogenesis of depressive disorders, the relationship of prostaglandins, known mediators of inflammation, and depression has not been elucidated. Clomipramine is an antidepressive drug with a pro-depressive paradoxical effect in adult rats when administrated neonatally. Using this effect as a model of depression, we investigated the differential expression of the cyclooxygenase (COX-2) gene in rat brains. Rats injected neonatally with clomipramine showed depressive-like symptoms in adulthood, as well as decreased levels of the brain-derived neurotrophic factor (BDNF) and a quantitative differential expression of the COX-2 gene (Real Time PCR) and protein (immunohistochemistry) in the hippocampus. As evidenced, the relationship between a key enzyme in the prostaglandin synthesis and biological and behavioral depression-like changes opens an interesting line of investigation regarding the molecular bases of depression and its potential treatment through immunomodulatory drugs.

Animals↗

PubMed2006

[Modelling of the geometry of the external auditory canal by the finite elements method].

The aim of this work is to design a computerized 3-D model of the human external ear, based on the finite elements method. The method consists to splitting a specific special area in a simple element net connected between themselves by nodes. The elements are associated to equations that define their physical characteristics. We realize a coupling with the middle ear model to know the behaviour of both systems with an acoustic excitation without the use of real measures or biological models. The model simulates the acoustic and biomechanic characteristics of the human external auditory canal. The development of a computerized model allows a better knowledge of the external ear mechanic-acoustic behaviour, this makes easier understand the physiology of the human external ear.

Acoustic Impedance Tests↗

PubMed2006

Effect of antiretroviral therapy on admissions of HIV-infected patients to an intensive care unit.

OBJECTIVES: To analyse the characteristics of HIV-infected patients admitted to an Intensive Care Unit (ICU) and to compare them in the pre-highly active antiretroviral therapy (HAART) and HAART eras. METHODS: All HIV-infected patients who were admitted to the ICU of our hospital between January 1990 and December 2003 were reviewed. Patients were divided into two groups based on whether they were admitted before or after the advent of HAART, the cut-off date being 31 December 1996. RESULTS: Data were collected on 66 patients, 17 in the pre-HAART and 49 in the HAART era. The proportion of HIV-infected patients admitted to the ICU in our HIV-infected population increased after the introduction of HAART (3.8 vs 0.5%; P=0.001), and the largest diagnostic group was respiratory pathology in both periods. More than a third of patients were diagnosed with HIV infection during the ICU income, and only 31.2% were on antiretroviral therapy. The in-hospital mortality was 53.0%, and later survival was high. There were no significant differences between the pre-HAART and HAART eras. CONCLUSIONS: Our results suggest that the characteristics of HIV-infected patients admitted to ICU have not changed: respiratory diseases are still the most frequent cause of admission, in-hospital mortality is high, and later survival rates are good.

AIDS-Related Opportunistic Infections↗

PubMed2006

Rectovaginal fistula following colectomy with an end-to-end anastomosis stapler for a colorectal adenocarcinoma.

An 11-year-old, female neutered Labrador retriever was presented with a micro-invasive differentiated papillar adenocarcinoma at the colorectal junction. A colorectal end-to-end anastomosis stapler device was used to perform resection and anastomosis using a transanal technique. A rectovaginal fistula was diagnosed two days later. An exploratory laparotomy was conducted and the fistula was identified and closed. Early dehiscence of the colon was also suspected and another colorectal anastomosis was performed using a manual technique. Comparison to a conventional manual technique of intestinal surgery showed that the use of an automatic staple device was quicker and easier. To the authors' knowledge, this is the first report of a rectovaginal fistula occurring after end-to-end anastomosis stapler colorectal resection-anastomosis in the dog. To minimise the risk of this potential complication associated with the limited surgical visibility, adequate tissue retraction and inspection of the anastomosis site are essential.

Adenocarcinoma↗

PubMed2006

Safety profile of proton pump inhibitors according to the spontaneous reports of suspected adverse reactions.

OBJECTIVE: [corrected] To evaluate similarities and differences in safety among proton pump inhibitors (PPIs) under the usual conditions of prescription. METHODS: A search of spontaneous reports on adverse reactions associated with these drugs and registered between January 1, 2004 and December 31, 2004 was undertaken in the Spanish Pharmacovigilance System Database. We compared the frequency of reports with the consumption of PPIs, and analyzed the organ and system distribution for each PPI. Of the organ and system groups more commonly affected, diarrhea, myalgia, abnormal vision and hepatitis were selected for further analysis. RESULTS: Nearly 8 times more reports for omeprazole compared to other drugs were found but a similar difference was observed in their consumption. Skin and appendage disorders were more frequently reported for omeprazole and rabeprazole, the urinary, female reproductive and endocrine systems for lansoprazole, musculoskeletal for omeprazole and esomeprazole, vision for pantoprazole, rabeprazole and esomeprazole, gastrointestinal tract for omeprazole and lansoprazole and liver and biliary systems for omeprazole, lansoprazole and pantoprazole. Myalgia appears more often in younger patients than diarrhea, abnormal vision or hepatitis and shows longer periods of latency and recovery. The four adverse reactions analyzed were mainly reversible. CONCLUSION: A direct relationship was found between consumption and the number of reports. Some organ and system groups were affected by more than one PPI and this showed a specific pattern of group toxicity to these pharmacological agents. Some reports involved only lansoprazole and these require further analysis.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed2005

Lichtenstein inguinal hernioplasty: sutures versus glue.

INTRODUCTION: This was a prospective, randomised study undertaken from January 2001 to July 2003 firstly to assess the possibility of using glues to fix meshes, secondly to verify whether or not this leads to a higher hernia recurrence rate, and thirdly to assess post-operative pain. METHODS: This study covered a total of 55 patients with bilateral hernias who presented similar characteristics on both sides and on whom fixation of the mesh was undertaken differently, depending on the side. On the right side polypropylene sutures were used (prolene 2/0), while on the left, attachment was done using glue (Tissucol). RESULTS AND CONCLUSIONS: Results were similar in both inguinal regions, although there was less post-operative pain and less inflammatory reaction on the left side. There was no hernia recurrence in the follow-up at the end of 1 year.

Aged↗

PubMed2005

Cross-neurotization of the caudal brachial plexus with the contralateral C-8 ventral nerve branch in the cat. Potential surgical applications, effects of graft collection on the healthy donor limb and results.

Contralateral transfer of the right, eighth ventral nerve branch (C8) (C8 cross-transfer - C8CT) was performed in 6 adult cats, in which the caudal part of the left brachial plexus (C8 and T1) had been severed, in order to mimic nerve root avulsion. Clinical and electrophysiological parameters, muscle contraction force measurements and histology were used to evaluate the effects of the surgery in a 14- to 36-month follow-up. The right forelimb (donor side) was clinically normal (no lameness) in all the cats at the end of the study. Electromyography performed 14 days after surgery revealed denervation fibrillation potentials in both forelimbs. Fibrillation potentials disappeared in all the cats at the end of the study. Direct stimulation of the right C8 ventral branch induced motor and sensory evoked potentials in the left limb muscles in all the cats. The left to right contraction ratio of the extensor carpi radialis muscle was approximately 1. This experimental study demonstrates that C8CT enables re-innervation of the contralateral brachial plexus and allows the establishment of new functional neuromuscular units. This can in turn enable the restoration of function, and could potentially lead to partial recovery after caudal brachial plexus avulsion in the cat.

Action Potentials↗

PubMed2004

Feasibility of CT scan-guided Tru-Cut serial liver biopsies to evaluate pharmacodynamic endpoints in patients with liver metastasis treated with experimental drugs.

We assessed the feasibility of using computed tomographically guided, Tru-Cut serial liver biopsies to perform pharmacodynamic studies in patients with liver metastasis who had been treated with experimental drugs. Twenty-three patients with liver metastasis were enrolled in two protocols for evaluation of the response to two new biologic drugs: a farnesyltransferase inhibitor and a tyrosine kinase inhibitor of the epidermal growth factor receptor. Computed tomographically guided Tru-Cut biopsies with an 18-gauge needle were performed. The procedure was performed at baseline and 2, 6, and 24 h after starting the administration of the drug. The procedures were scheduled on an outpatient basis. We obtained 271 samples (168 from metastatic lesions and 103 from surrounding normal liver tissue) from 23 patients. Biochemical determination of farnesyltransferase activity and different immunohistochemistry stainings (pEGRF, pMAPK, p27, Ki67, and apoptosis) of the signal transduction pathway were determined in each tissue sample, and all scheduled tissue assays were performed with the tissues obtained. Complete serial biopsies were performed in 20 patients. Three patients were excluded due to minor complications after the first biopsy. The morbidity rate in relation to the number of procedures was 1.1% (three of 271 samples). We found serial liver biopsies using Tru-Cut to be a safe and easy procedure. In our series, we could evaluate samples for molecular changes that influence the optimal dose, sequence, and schedule of the new antineoplastic agents.

Alkyl and Aryl Transferases↗

PubMed2004

Safety, immunogenecity, and efficacy of an autoclaved Leishmania amazonensis vaccine plus BCG adjuvant against New World cutaneous leishmaniasis.

The safety, immunogenecity, and efficacy of two doses of an autoclaved-killed, whole cell Leishmania amazonensis vaccine (IFLA/BR/67/PH8) and BCG adjuvant (n = 750) against cutaneous leishmaniasis (CL) was compared with placebo (n = 756) in a randomized, placebo-controlled, blinded study. Systemic and local side-effects were more frequent in the vaccine than placebo group. Leishmanin skin test (LST) conversion was greater in the vaccine than placebo group 2 months after the second vaccination dose (74.4% versus 14.7%; P = 0.000001). The 26-month incidence of confirmed CL (n = 25) was similar between the vaccine (2.0%) and placebo groups (2.0% versus 1.3%; P > 0.05). LST conversion was not associated with CL protection and the vaccine did not offer significant protection against CL infection caused by L. Viannia spp. compared to placebo.

Adjuvants, Immunologic↗

PubMed2003

Neuron-glia interactions during axon guidance in Drosophila.

Axons navigate to trace stereotypic trajectories over an environment often rich in glial cells. Once axonal trajectories are defined, their structuring proceeds through multiple fasciculation and defasciculation events, to finally establish the mature bundles. Fasciculation and ensheathment also proceed in close association between axons and glial cells, and ultimately require glia. The cross-talk between axons and glia during axon guidance is manifested in: (i) axonal fasciculation and bundling, promoted by glia; (ii) growth cone guidance, as glia function as guidepost cells at choice points; (iii) glial migration patterns, which are influenced by neurons; (iv) cell survival control, which constrains position and number of both cell types; and (iv) connectivity, where an axon contacts its final target aided by glial cells. Understanding the reciprocal interactions between neurons and glia during guidance and fasciculation is absolutely necessary to implement repair of axonal trajectories upon damage. Drosophila can be used as a model system for these purposes.

Animals↗

PubMed2003

A catalogue of molecular, physiological and symbiotic properties of soybean-nodulating rhizobial strains from different soybean cropping areas of China.

We have analysed 198 fast-growing soybean-nodulating rhizobial strains from four different regions of China for the following characteristics: generation time; number of plasmids; lipopolysaccharide (LPS), nodulation factors (LCOs) and PCR profiles; acidification of growth medium; capacity to grow at acid, neutral, and alkaline pH; growth on LC medium; growth at 28 and 37 degrees C; melanin production capacity; Congo red absorption and symbiotic characteristics. These unbiased analyses of a total subset of strains isolated from specific soybean-cropping areas (an approach which could be called "strainomics") can be used to answer various biological questions. We illustrate this by a comparison of the molecular characteristics of five strains with interesting symbiotic properties. From this comparison we conclude, for instance, that differences in the efficiency of nitrogen fixation or competitiveness for nodulation of these strains are not apparently related to differences in Nod factor structure.

Bacterial Proteins↗

PubMed2003

A simple method for the construction of small format tissue arrays.

Tissue arrays can evaluate molecular targets in high numbers of samples in parallel. Array construction presents technical difficulties and tissue arrayers are expensive, particularly for small and medium sized laboratories. This report describes a method for the construction of 36 sample arrays using widely available materials. A blunted 16 gauge needle for bone marrow aspiration was used to extract paraffin wax cylinders and manually define a 6 x 6 matrix on a blank paraffin wax block. Tissue cores from 36 paraffin wax embedded premalignant lesions and invasive cervical carcinomas were injected into the matrix using a 14 gauge needle. This tissue array was sectioned using a standard microtome and used for the immunodetection of CD44 variant 9 and interleukin 18 with satisfactory results. This method can be applied in any laboratory, without the need of specialised equipment, offering a good alternative for the wider application of tissue arrays.

Biomarkers, Tumor↗

PubMed2002

Accuracy of high-resolution CT in distinguishing between Pneumocystis carinii pneumonia and non- Pneumocystis carinii pneumonia in AIDS patients.

The aim of this study was to assess the value of high-resolution CT in distinguishing between Pneumocystis carinii and non- Pneumocystis carinii pneumonia (PCP) in patients HIV-positive and high risk to have PCP. We performed a prospective study in 30 patients with <200 CD4 lymphocytes, clinical symptoms of pulmonary disease and chest X-ray non-conclusive for pulmonary infection. Evaluated CT findings included ground-glass opacities, reticulation, tree-in-bud appearance, consolidation, cystic lesions, bronchiectasis and lymphadenopathies. The diagnosis of "examination suggestive of PCP" was applied to cases showing a diffuse or predominant ground-glass pattern in the upper fields, associated or not with reticulations and small cystic lesions. The sensitivity, specificity, positive predictive value and negative predictive value of high-resolution computed tomography (HRCT) for the diagnosis of PCP was 100, 83.3, 90.5 and 100%, respectively. Pneumocystis carinii pneumonia was not demonstrated in any of the cases classified as "examination not suggestive of PCP". Significant small airway disease was not observed in any of the PCP cases. We conclude that HRCT is a reliable method for differentiating PCP from other infectious processes in HIV-positive patients and a good method to rule our PCP. Its inclusion in the diagnostic algorithm of lung infections is justified in these patients.

AIDS-Related Opportunistic Infections↗

PubMed2002

Biodegradation of phenol in synthetic and industrial wastewater by Rhodococcus erythropolis UPV-1 immobilized in an air-stirred reactor with clarifier.

Phenol biodegradation by suspended and immobilized cells of Rhodococcus erythropolis UPV-1 was studied in discontinuous and continuous mode under optimum culture conditions. Phenol-acclimated cells were adsorbed on diatomaceous earth, where they grew actively forming a biofilm of short filaments. Immobilization protected cells against phenol and resulted in a remarkable enhancement of their respiratory activity and a shorter lag phase preceding active phenol degradation. Under optimum operation conditions in a laboratory-scale air-stirred reactor, the immobilized cells were able to completely degrade phenol in synthetic wastewater at a volumetric productivity of 11.5 kg phenol m(-3) day(-1). Phenol biodegradation was also tested in two different industrial wastewaters (WW1 and WW2) obtained from local resin manufacturing companies, which contained both phenols and formaldehyde. In this case, after wastewater conditioning (i.e., dilution, pH, nitrogen and phosphorous sources and micronutrient amendments) the immobilized cells were able to completely remove the formaldehyde present in both waters. Moreover, they biodegraded phenols completely at a rate of 0.5 kg phenol m(-3) day(-1) in the case of WW1 and partially (but at concentrations lower than 50 mg l(-1)) at 0.1 and 1.0 kg phenol m(-3) day(-1) in the cases of WW2 and WW1, respectively.

Biodegradation, Environmental↗

PubMed2002

Formaldehyde removal in synthetic and industrial wastewater by Rhodococcus erythropolis UPV-1.

Rhodococcus erythropolis strain UPV-1 is able to grow on phenol as the only carbon and energy source and to remove formaldehyde completely from both synthetic and industrial wastewater. The rate of formaldehyde removal is independent of either initial biomass or formaldehyde concentration. The presence of viable, intact cells is strictly necessary for this removal to take place. Discontinuous and continuous formaldehyde-feed systems were successfully tested with synthetic wastewater in shaken flasks. Once biodegradation was well established in model synthetic wastewater, a real wastewater sample was obtained from a local phenolic and melamine resin-manufacturing company. Incubation of biomass with this wastewater at subtoxic concentrations of formaldehyde resulted in the complete removal of the pollutant. Parameters, such as chemical oxygen demand and toxicity, were assessed as indicators of wastewater cleanup progress.

Biodegradation, Environmental↗

PubMed2001

Increases in ornithine decarboxylase activity in the positive inotropism induced by androgens in isolated left atrium of the rat.

It is well established that the intracellular receptors of androgens act as transcription factors upon their activation by androgen binding. However, a growing number of studies have associated androgens with rapid biological responses independent of their classical action mechanism. In this sense, 5alpha- and 5beta-dihydrotestosterone elicited a rapid positive inotropism in the isolated left atrium of the rat via cAMP-dependent mechanisms that may involve genomic effects. In addition, polyamines are mediators of several biological actions including those acute and long-term effects induced by androgens in the heart. The present study analyzed the role of polyamine synthesis in the cardiotonic effect of androgens in the left atrium of male Wistar rats, electrically stimulated (0.5 Hz, 5 ms and supramaximal voltage) and placed in an organ bath in 10 ml of Tyrode's solution. Incubation in the organ bath with an inhibitor of ornithine decarboxylase activity, alpha-difluoromethylornithine 10 mM, significantly decreased the positive inotropism induced by 5alpha- and 5beta-dihydrotestosterone (0.1-100 microM). This suggests that ornithine decarboxylase seems to be involved in androgen-induced positive inotropism. Furthermore, 6-min exposure to 5alpha- or 5beta-dihydrotestosterone significantly increased the activity of ornithine decarboxylase from 61.81+/-7.53 (control) to 93.28+/-9.45 and 80.28+/-12 pmol/h/mg of protein, respectively. Northern blot analysis showed that 5alpha- and 5beta-dihydrotestosterone did not modify the level of expression of the ornithine decarboxylase gene. Therefore, our results suggest that polyamine synthesis might be involved in the positive inotropism elicited by androgens through the stimulation of ornithine decarboxylase activity without changes in the expression of the ornithine decarboxylase gene.

Androgens↗

PubMed2001

Involvement of K(ATP) channels in diethylstilbestrol-induced relaxation in rat aorta.

The estrogens prevent cardiovascular diseases that among other effects could be related to the modulation of the vascular tone via modifying ionic channel permeability. ATP-sensitive K(+) (K(ATP)) channels seem to be involved in diethylstilbestrol-induced relaxation in isolated rat aorta precontracted by noradrenaline (30 nM), since the effect is inhibited by glibenclamide (1--10 microM), and 1 mM tetraethylammonium, but not by 30 mM tetraethylammonium or paxilline. The antiestrogen tamoxifen, the inhibitor of protein kinase A, Rp-cAMPS, and the inhibitor of ornithine decarboxylase, difluoromethylornithine, antagonized diethylstilbestrol-induced relaxation. The association of glibenclamide with these compounds separately did not modify the effect of glibenclamide alone on diethylstilbestrol-induced relaxation. Functional K(ATP) channels are present in rat aorta, since diazoxide induced relaxation sensitive to glibenclamide. Papaverine, dibutyryl cyclic AMP and spermine relaxed isolated rat aorta although this was not sensitive to glibenclamide. The relaxation to forskolin was antagonized by glibenclamide. We conclude that diethylstilbestrol-induced relaxation in rat aorta is related to the modulation of K(ATP) channels. Cyclic AMP-dependent mechanisms and polyamine synthesis may mediate this modulation.

Animals↗

PubMed2001

Chemokine stromal cell-derived factor-1alpha modulates VLA-4 integrin-mediated multiple myeloma cell adhesion to CS-1/fibronectin and VCAM-1.

The chemokine stromal cell-derived factor-1alpha (SDF-1alpha) and its G-protein-linked receptor CXCR4 are involved in hematopoietic progenitor cell and lymphocyte migration. The integrin VLA-4 is a cell adhesion receptor for CS-1/fibronectin and VCAM-1 and constitutes one of the main adhesion receptors mediating myeloma cell adhesion to bone marrow (BM) stroma in multiple myeloma (MM). It is shown here that MM CD38(hi)CD45RA(-) BM cells and myeloma-derived cell lines expressed CXCR4 and displayed a moderate chemotactic response to SDF-1alpha. Because cell migration in response to SDF-1alpha might require a dynamic regulation of integrin function, it was investigated whether SDF-1alpha can modulate VLA-4 function on myeloma cells. SDF-1alpha rapidly and transiently up-regulated VLA-4-mediated myeloma cell adhesion to both CS-1/fibronectin and VCAM-1, which was inhibited by pertussis toxin and cytochalasin D, indicating the involvement of G(i) protein downstream signaling and an intact cytoskeleton. Modulation of VLA-4-dependent myeloma cell adhesion by SDF-1alpha could contribute to the trafficking and localization of these cells in the BM microenvironment.

Bone Marrow Cells↗