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Biomedical subjects

E Alvarez

Publications and source records attributed to E Alvarez.

At least 19 recordsLinked to original sources
PubMed2006

Identification and physical mapping of induced translocation breakpoints involving chromosome 1R in rye.

To obtain translocations involving specific chromosomes in rye, pollen of a line in which chromosome 1R has large C-bands on its two telomeres, but which lacks C-bands (or has very small ones) on the telomeres of the remaining chromosomes, was X-irradiated. All translocations involving the labelled chromosome (1R) could be easily recognized in C-banded mitotic metaphases. The non-labelled chromosome involved in each translocation was identified either from mitotic C-banding analysis or from the meiotic configurations observed in some specific progenies. A physical map including 40 translocation breakpoints has been developed by means of synaptonemal complex (SC) analysis of well-paired pachytene quadrivalents. The results agree with the hypothesis of chromosomes 2R to 7R having similar probabilities of participating in translocations with chromosome 1R. However, the locations of the breakpoints are not entirely random: an excess of translocation breakpoints located on the short arm of chromosome 1R was obtained, and the two acentric translocated segments of each translocation show a trend towards having similar sizes. The possible reasons for these two non-random situations are discussed.

Chromosome Banding↗
PubMed2006

Improved incidence of pT0 downstaged surgical specimens in locally advanced rectal cancer (LARC) treated with induction oxaliplatin plus 5-fluorouracil and preoperative chemoradiation.

PURPOSE: To compare efficacy in terms of pathologic response in LARC patients treated with preoperative chemoradiation, with or without a short-intense course of induction oxaliplatin. PATIENTS AND METHODS: From 05/98 to 10/02, 114 patients were treated with preoperative chemoradiation (4500-5040 cGy + oral Tegafur 1200 mg/day) for cT(3)-(4)N(+/x)M(0) rectal cancer. Starting 05/01, 52 consecutive patients additionally received induction FOLFOX-4, oxaliplatin (85 mg/m(2) iv d1), 5-FU (400 mg/m(2) iv bolus d1) and 600 mg/m(2) iv continuous infusion in 22 h with leucovorin (200 mg iv) d1 and d2, every 15 days (2 cycles), followed by the previously described Tegafur chemoradiation regime. Surgery was performed in 5-6 weeks. Pathological assessment investigated post-treatment T and N status in the rectal wall and peri-rectal tissues. RESULTS: Patients, tumor and treatment characteristics were comparable between groups. Incidence of pT(0) specimens was significantly increased by induction FOLFOX-4 (P = 0.006). Total T and N downstaging were 58% versus 75% and 42% versus 40%, respectively (P = ns). T downstaging of > or =2 categories was significantly superior in FOLFOX-4 group (P = 0.029). CONCLUSIONS: Short-intense induction FOLFOX-4 significantly improves pathologic complete response in LARC patients treated with tegafur-sensitized preoperative chemoradiation. The 44% rate of pT(0)-(1) specimens observed in the oxaliplatin group should impulse innovative surgical approaches to promote ano-rectal sphincter conserving protocols.

Adult↗
PubMed2006

Identification of type-specific and cross-reactive neutralizing conformational epitopes on the major capsid protein of human papillomavirus type 31.

The majority of the neutralizing epitopes of papillomaviruses (PV) are conformation-specific and have not been fully characterised. Studies have, to date, been limited to a few HPV types only. We analysed the epitopes on the major capsid protein (L1) of Human papillomavirus (HPV) type 31 using monoclonal antibodies (MAbs) generated against HPV-31 virus-like particles (VLPs). The type-specific MAbs against HPV-31 were all found to be neutralizing and recognized conformation-dependent epitopes. Two other MAbs directed against a conformational epitope were found to be cross-reactive with other HPV types, and one of them was found to be cross-neutralizing. Cross-reactive antibodies were further investigated using wild-type HPV-16 L1 VLPs and two mutants. The results obtained suggested the existence of a cross-neutralizing conformational epitope at the N-terminal part of the FG loop of the major capsid protein, and the other four cross-reactive MAbs recognized epitopes also located at the N-terminal part of the FG loop.

Amino Acid Sequence↗
PubMed2006

Tissue banking in Mexico.

INTRODUCTION: Here, we describe our Tissue Banking experiences of 4 years of activity in Mexico. METHODS: Data of allografts provided by our Bank and bone retrievals performed by our teams between February of 2001 and August of 2004 were included. RESULTS: There were 100 bone donors, a total of 1,107 tissues were obtained with an average of 11 tissues by retrieval, samples from all tissues were obtained during retrieval and cultured for bacterial contamination, 250 tissues were positives to bacterial growth with an average of 22.58% of bacterial contamination of tissue by retrieval. A total of 4,493 allografts were provided and were utilized in 3,643 patients. The allografts were used mainly by orthopedic surgeons (62%) and dentists (30%). The most used allografts were morcellized cancellous bone 31%, pulverized 25% and chips of cancellous bone 20%. Among orthopedic patients the most frequent procedures were related with spine degenerative diseases 39.09%, followed by non-pathological fractures and its complications 28.67% and bone tumors and cystic bone lesions 11.59%. CONCLUSIONS: Sustained increase of allograft utilization in Mexico reflects a great necessity for them in our country. The increase in public awareness about tissue donation has allowed an increase in tissue donations and retrievals.

Adult↗
PubMed2006

Injectable atypical antipsychotics for agitation in borderline personality disorder.

Agitation is relatively common among Borderline Personality Disorder (BPD) patients in Psychiatric Emergency Services (PES). New injectable atypical antipsychotics are indicated for treatment in agitated psychotic or maniac patients but not for agitated BDP patients. Twenty agitated BPD patients were treated with intramuscular atypical antipsychotics (olanzapine or ziprasidone). Results suggest intramuscular atypical antipsychotics may be effective, fast and safe for treating acute BPD patients.

Adult↗
PubMed2006

Effects of policosanol on patients with ischemic stroke: a pilot open study.

Stroke is a major health problem worldwide. Its pharmacological management includes thrombolytic therapy for the acute phase and antiplatelet drugs for stroke recovery and prevention. Statins can help in the acute phase and in preventing stroke in secondary prevention patients. Policosanol is a cholesterol-lowering drug with concomitant antiplatelet effects, with protective effects in stroke models. This observational study investigated the effects of policosanol (20 mg/day) administered during the acute phase and for 5 years later on the neurological recovery of patients with ischemic stroke treated with antiplatelets and vitamins. After hospital discharge, patients were followed up every 3 (first year) and 6 (thereafter) months. Neurological improvement was assessed with the modified Canadian Neurological Scale. Adverse events were recorded. Fifty patients were included; all completed the study. Neurological score improved throughout the study. No patient died, and most [40 (80.0%)] did not experience new vascular events; only one (2.0%) suffered a new stroke, and two (4.0%) suffered more than one transient ischemic attack. The time to the first recurrent event was 46.2 months. Policosanol persistently lowered serum total cholesterol, with such reduction correlating with the neurological improvement (R = 0.995253301). Triglycerides were unchanged. Treatment was well tolerated. Policosanol administered to patients suffering ischemic stroke treated with aspirin and vitamins showed good results on neurological outcomes and recurrent events. This study, however, has limitations, since it was open and uncontrolled, and patients also consumed aspirin and vitamins. New randomized, controlled studies are needed to assess the usefulness of policosanol in stroke management.

Aged↗
PubMed2006

Digital imaging of patterns of dental wear to diagnose bruxism in children.

OBJECTIVE: The aim of this study was to evaluate and compare the area, perimeter, and form (D factor and fractal dimension) of the dental wear among bruxist and nonbruxist children with mixed dentition in order to determine if the dental wear may be used as criteria to diagnose bruxism. METHODS: The children were 8 to 11 years old and were classified as bruxist or nonbruxist, according to anxiety level and temporomandibular disorders. Dental casts of the upper arch were obtained for the bruxist (n = 24) and the control (n = 29) group. The dental wear was measured in digital format and processed automatically. The complete and pathological dental wear was compared between the two groups, using the Student's t-test and Mann-Whitney test. RESULTS: Statistically significant differences were observed between the two groups, with a higher area, perimeter, and more irregular form of the pathological dental wear among the bruxist group. Regarding complete dental wear, differences were only significant for the D factor (an un-dimensional quantitative parameter which produces a relation between the area and the perimeter of an object). CONCLUSION: Digital imaging of dental wear may be used as criteria to diagnose bruxism in children with mixed dentition after making an analysis of the area, perimeter, and irregularity of the form of pathological dental wear.

Anxiety↗
PubMed2005

Scientific management of Mediterranean coastal zone: a hybrid ocean forecasting system for oil spill and search and rescue operations.

The oil spill from Prestige tanker showed the importance of scientifically based protocols to minimize the impacts on the environment. In this work, we describe a new forecasting system to predict oil spill trajectories and their potential impacts on the coastal zone. The system is formed of three main interconnected modules that address different capabilities: (1) an operational circulation sub-system that includes nested models at different scales, data collection with near-real time assimilation, new tools for initialization or assimilation based on genetic algorithms and feature-oriented strategic sampling; (2) an oil spill coastal sub-system that allows simulation of the trajectories and fate of spilled oil together with evaluation of coastal zone vulnerability using environmental sensitivity indexes; (3) a risk management sub-system for decision support based on GIS technology. The system is applied to the Mediterranean Sea where surface currents are highly variable in space and time, and interactions between local, sub-basin and basin scale increase the non-linear interactions effects which need to be adequately resolved at each one of the intervening scales. Besides the Mediterranean Sea is a complex reduced scale ocean representing a real scientific and technological challenge for operational oceanography and particularly for oil spill response and search and rescue operations.

Disaster Planning↗
PubMed2005

First enantiospecific synthesis of the antitumor marine sponge metabolite (-)-15-oxopuupehenol from (-)-sclareol.

[reaction: see text] A new route toward puupehenone-related bioactive metabolites from (-)-sclareol, based on the palladium(II)-mediated diastereoselective cyclization of a drimenylphenol, is described. Utilizing this, the first enantiospecific synthesis of the antitumor and antimalarial (-)-15-oxopuupehenol, together with improved syntheses of (+)-puupehenone, (+)-puupehedione, and (+)-15-cyanopuupehenone, were accomplished.

Animals↗
PubMed2005

Cognitive and emotional functions of the teleost fish cerebellum.

Increasing experimental and neuropsychological evidence indicates that the cerebellum of humans and other mammals, traditionally associated with motor control, is implicated in a variety of cognitive and emotional functions. For example, the cerebellum has been identified as an essential structure in different learning processes, ranging from simple forms of associative, sensory-motor learning and emotional conditioning, to more complex, higher-order processes such as spatial cognition. Although neuroanatomical and neurophysiological data indicate that the organization of the cerebellum is notably well conserved in vertebrates, little is actually known about the cerebellar contribution to processes besides the motor domain in non-mammals. In this work, we analyzed the involvement of the teleost fish cerebellum on classical conditioning of motor and emotional responses and on spatial cognition. Cerebellum lesions in goldfish impair the classical conditioning of a simple eye-retraction response analogous to the eyeblink conditioning described in mammals. Single unit extracellular electrophysiological recording and cytochrome oxidase histochemistry also reveal the involvement of the teleost fish cerebellum in classical conditioning. Autonomic emotional responses (e.g., heart rate classical conditioning) are also impaired by cerebellum lesions in goldfish. Furthermore, goldfish with cerebellum lesions present a severe impairment in spatial cognition. In contrast, cerebellum lesions do not produce any observable motor deficit as indicated by the swimming activity or obstacle avoidance and do not interfere with the occurrence of unconditioned motor or emotional responses. These data indicate that the functional involvement of the teleost cerebellum in learning and memory is strikingly similar to mammals and suggest that the cognitive and emotional functions of the cerebellum may have evolved early in vertebrate evolution, having been conserved along the phylogenetic history of the extant vertebrate groups.

Animals↗
PubMed2005

Bilateral subthalamotomy in Parkinson's disease: initial and long-term response.

We conducted an open label pilot study of the effect of bilateral subthalamotomy in 18 patients with advanced Parkinson's disease. In seven patients, the first subthalamotomy pre-dated the second by 12-24 months ('staged surgery'). Subsequently, a second group of 11 patients received bilateral subthalamotomy on the same day ('simultaneous surgery'). Patients were assessed according to the CAPIT (Core Assessment Program for Intracerebral Transplantation) protocol, a battery of timed motor tests and neuropsychological tests. Evaluations were performed in the 'off' and 'on' drug states before surgery and at 1 and 6 months and every year thereafter for a minimum of 3 years after bilateral subthalamotomy. Compared with baseline, bilateral subthalamotomy induced a significant (P < 0.001) reduction in the 'off' (49.5%) and 'on' (35.5%) Unified Parkinson's Disease Rating Scale (UPDRS) motor scores at the last assessment. A blind rating of videotape motor exams in the 'off' and 'on' medication states preoperatively and at 2 years postoperatively also revealed a significant improvement. All of the cardinal features of Parkinson's disease as well as activities of daily living (ADL) scores significantly improved (P < 0.01). Levodopa-induced dyskinesias were reduced by 50% (P < 0.01), and the mean daily levodopa dose was reduced by 47% at the time of the last evaluation compared with baseline (P < 0.0001). Dyskinesias occurred intraoperatively or in the immediate postoperative hours in 13 patients, but were generally mild and short lasting. Three patients developed severe generalized chorea that gradually resolved within the next 3-6 months. Three patients experienced severe and persistent postoperative dysarthria. In two, this coincided with the patients exhibiting large bilateral lesions also suffering from severe dyskinesias. No patient exhibited permanent cognitive impairment. The motor benefit has persisted for a follow-up of 3-6 years. This study indicates that bilateral subthalamotomy may induce a significant and long-lasting improvement of advanced Parkinson's disease, but the clinical outcome was variable. This variability may depend in large part on the precise location and volume of the lesions. Further refinement of the surgical procedure is mandatory.

Activities of Daily Living↗
PubMed2005

[Hematuria and sharp renal failure as debut of secondary bladder amiloidosis. Presentation of a new case and revision of the literature].

The primary bladder amiloidosis is an uncommon pathology, not existing in the world more than 150 published cases, being even more exceptional the secondary bladder amiloidosis being described around 25 cases. The secondary bladder amiloidosis associates in most from the patients to arthritis reumatoide of long evolution. The diagnoses clinical it is difficult, being necessary the differential diagnosis with the bladder tumour. The pathological study and inmunohistochemics, confirm the diagnosis. We present the case of a patient that I debut with frank hematuria, hemodynamic uncertainty and renal inadequacy that it required combined treatment, doctor and surgical for the resolution of their square.

Aged↗
PubMed2005

[Myofibroblastic tumor of bladder].

The myofibroblastic tumor, is a mesenchymal benign tumor of exceptional character, being its localization but habitual it is the lung; while its appearance in the bladder, is exceptional, not existing but of 100 published cases, of this tumor type in the bladder. This tumor type that clinic and radiologics, behave as a wicked tumor. The pathological diagnosis is complex, due to its similarity with the sarcomas, being necessary to appeal to the inmunohistochemics for a I diagnose of certainty. The treatment by means of wide resection is usually enough not existing any case of metastasis at the present time at distance, neither of malignization. We present a new case of this neoplasm, carrying out a wide bibliographical revision.

Diagnosis, Differential↗
PubMed2005

Human fibroblast growth factor 20 (FGF-20; CG53135-05): a novel cytoprotectant with radioprotective potential.

The aim was to evaluate the radioprotective properties of recombinant human fibroblast growth factor 20 (FGF-20; CG53135-05) in vitro and in vivo and to examine its effects on known cellular pathways of radioprotection. Relative transcript levels of the cyclooxygenase 2 (COX2), Mn-super oxide dismutase (SOD), CuZn-SOD, extracellular (EC)-SOD, nuclear respiratory factor 2 (Nrf2), glutathione peroxidase 1 (GPX1) and intestinal trefoil factor 3 (ITF3) genes, which are involved in radiation response pathways, were assessed by reverse transcriptase-polymerase chain reaction (RT-PCR) in NIH/3T3, IEC18, CCD-18Co, CCD-1070sk and human umbilical vein endothelial cells (HUVEC) cells exposed to FGF-20. Activation of the radioprotective signal transduction pathways initiating with the serine/threonine Akt kinase and the extracellular regulated kinase (ERK) were analysed. Levels of intracellular hydrogen peroxide and cytosolic redox potential were also measured in irradiated and unirradiated cells in the presence or absence of FGF-20. The effects of FGF-20 on cell survival in vitro following ionizing radiation were evaluated using clonogenic assays. To test the potential activity of FGF-20 as a radioprotectant in vivo, mice were administered a single dose of FGF-20 (4 mg kg(-1), intraperitoneally (i.p.) 1 day before lethal total-body irradiation and evaluated for survival. In vitro exposure to FGF-20 increased expression of the Nrf2 transcription factor and oxygen radical scavenging enzymes such as MnSOD, activated signal transduction pathways (ERK and Akt) and resulted in increased survival of irradiated cells in vitro. FGF-20 treatment also resulted in a concomitant reduction in intracellular levels of injurious reactive oxygen species (ROS) following acute ionizing irradiation. Finally, prophylactic administration of FGF-20 to mice before potentially lethal, whole-body X-irradiation led to significant increases in overall survival. FGF-20 reduced the lethal effects of acute ionizing radiation exposure in cells by up-regulating important signalling and free radical scavenging pathways. Survival-sparing effects of FGF-20 prophylaxis in acutely irradiated mice presumably are elicited by comparable mechanisms. These results indicate that FGF-20, has significant radioprotective attributes with potential applications in clinical and non-clinical exposure settings.

Animals↗
PubMed2005

General characterization of noncommercial microbial lipases in hydrolytic and synthetic reactions.

Fourteen noncommercial preparations of microbial lipases were investigated with respect to their catalytic activity for hydrolysis and synthesis of ester bonds. Six of the lipases were derived from microorganisms that have not previously been described as lipase producers, and another four were characterized for the first time. The synthetic reactions were carried out in two solvents of different polarities (n-heptane and acetone) using a series of fatty acids and primary and secondary alcohols with different chain lengths. Under the culture conditions employed, Pseudomonas cepacia produced more active enzyme than the other microorganisms. The lipase preparations produced using Ovadendron sulphureo-ochraceum, Monascus mucoroides, Monascus sp., Fusarium oxysporum, Penicillium chrysogenum, Rhodotorula araucariae, Pseudomonas cepacia, Streptomyces halstedii, and Streptomyces sp.were the most efficient catalysts for hydrolysis at lipid-water interfaces. Enzyme preparations from P. cepacia, Streptomyces sp., S. halstedii, and R. araucariae were good biocatalysts for esterification in the polar medium (acetone). When the lipase preparations with the greatest activity for hydrolytic reactions were excluded, regression analysis of the data for the hydrolytic and synthetic activities of the remaining lipase preparations yielded high multiple correlation coefficients for these reactions in both n-heptane and acetone (R = 0.82 and 0.91, respectively).

Acetone↗
PubMed2004

CD44 and hyaluronic acid regulate in vivo iNOS expression and metalloproteinase activity in murine air-pouch inflammation.

OBJECTIVE: To evaluate the effects of anti-CD44 IM7.8.1 antibody, HMW-HA and LMW-HA on leukocyte migration and adhesion, and the induction of proinflammatory mediators, in mouse air-pouch inflammation induced by zymosan. METHODS: Leukocytes were obtained from zymosan-air pouches after the intra-pouch injection of anti-CD44 IM7.8.1, isotype control, HMW-HA, LMW-HA or PBS. TNF-alpha, IL-1beta and iNOS mRNA were estimated in leukocytes by semi-quantitative RT-PCR. Matrix metalloproteinases (MMPs) from exudates were evaluated by zymography and Western Blot. Adhesion and migration of leukocytes were evaluated in HA-coated plates and Boyden chambers respectively. RESULTS: IM7.8.1 decreased iNOS mRNA levels and the activity of both MMP-9 and MMP-2 eight h after injection into zymosan air pouch while IM7.8.1, HMW-HA and LMW-HA had no effect on IL1-beta or TNF-alpha mRNA levels. Leukocytes from air pouch adhered to and migrated in vitro against both HMW-HA and LMW-HA. LMW-HA increased the number of leukocytes in the air pouch and iNOS mRNA levels as compared to PBS injection. In contrast, HMW-HA decreased leukocyte count and reduced iNOS mRNA levels. Paradoxically, the activity of both MMP-9 and MMP-2 was increased by HMW-HA and decreased by LMW-HA. CONCLUSIONS: Both CD44 and HA can modulate leukocyte migration and induction of proinflammatory mediators in mouse zymosan air pouch inflammation. IM7.8.1 had consistent anti-inflammatory effects, reducing iNOS, MMP-9 and MMP-2. HMW-HA and LMW-HA were able to modulate both the induction of proinflammatory mediators and leukocyte count in the air pouch.

Animals↗