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Biomedical subjects

R Lozano

Publications and source records attributed to R Lozano.

At least 19 recordsLinked to original sources
PubMed2005

Development and mapping of a codominant SCAR marker linked to the andromonoecious gene of melon.

Monoecy is an important goal for melon breeding because of the agronomic advantages it provides to parental lines in that they do not require hand emasculation to develop monoecious F1 hybrids, the latter producing fruits of higher quality. Monoecious phenotype is conferred by the dominant allele of the andromonoecious (a) gene, whereas recessive homozygous plants are andromonoecious. A bulked segregant analysis (BSA) approach performed in a set of 38 double-haploid lines has allowed us to identify an AFLP marker linked to the a gene at 3.3 cM. Following cloning and sequencing of the AFLP fragment, specific PCR primers were designed and used in the amplification of a codominant SCAR marker. Using a backcrossed mapping population of 530 plants, the SCAR marker could be mapped near the a locus (5.5 cM). Size difference between the two allelic SCAR fragments is 42 bp and might be due to a deletion/insertion. The SCAR marker is closest to the a gene identified to date, and can be useful in breeding programs, using marker-assisted selection procedures to screen for sexual types in melon.

Cucumis melo↗
PubMed2005

The importance of histology in the evaluation of pulmonary transplantation: carcinomatous lymphangitis.

Pulmonary carcinomatous lymphangitis is a form of neoplastic metastatic spread to the lungs, which represents a poor prognosis for the patient. The physician may be confronted by a differential diagnosis with diffuse pulmonary interstitial affections requiring specific treatment, including lung transplantation. We present the case of a patient, diagnosed with pulmonary interstitial disease with rapidly progressive worsening of lung function, who was considered for lung transplantation. Videothoracoscopic lung biopsy demonstrated the existence of carcinomatous lymphangitis, which completely changed the therapeutic direction.

Contraindications↗
PubMed2004

[Validation of the Spanish version of the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ)].

OBJECTIVE: Validate the questionnaire Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) in conditions of regular clinical practice. METHODS: Two hundred and eighty four adult patients with a diagnosis of rhinoconjunctivitis (RC) cared in 37 centers of specialized health care in allergy or otorhinolaryngology services in Spain were analyzed. Patients with RC were included in two groups: clinically non-stable patients who received treatment with an oral second generation antihistaminic (group A), and clinically stable patients (group B). Sociodemographic and clinical variables were collected and the questionnaires RQLQ and EQ-5D were administered in the initial visit and in the second visit 15 days after. Feasibility, validity, reliability and sensitivity related to the change of the RQLQ were analyzed. RESULTS: The mean period (standard deviation) of administration was 9.67 (6.25) minutes and 85.6% of patients needed assistance in order to fill the RQLQ, especially the selection of the characteristics (62.5%). The dimensions of the RQLQ showed a greater association with the dimensions of the EQ-5D that assessed similar aspects and the symptoms in which a greater relation was expected. The alpha Cronbach coefficient of the scorings of the RQLQ fluctuated between 0.85 and 0.96 and the intraclass correlation coefficient fluctuated between 0.68 and 0.89. The sensitivity to the change of the dimensions of the RQLQ, evaluated through the magnitude of the effect between the two visits, ranged between 0.76 and 1.46. CONCLUSIONS: The Spanish version of the RQLQ proved to be a valid instrument for assessing the Health-Related Quality of Life (HRQL) in adult patients with seasonal or perennial RC.

Activities of Daily Living↗
PubMed2003

L-calcium channel blockade induced by diltiazem inhibits proliferation, migration and F-actin membrane rearrangements in human vascular smooth muscle cells stimulated with insulin and IGF-1.

During the atheroma plaque formation, smooth muscle cells (SMC) have to change their differentiated phenotype in order to proliferate, migrate and synthesize collagen. These phenotypic changes are stimulated by insulin and IGF-1, and we have studied the effect of L-type calcium channel blockade produced by diltiazem on such changes. Mitotic activity was measured using bromodeoxyuridine DNA incorporation, the migration capability as chemotaxis index in a Boyden chamber, and cytoskeleton changes related to SMC movement in immunofluorescence studies. Diltiazem (10(-7)-10(-6) M) reduced insulin-induced mitotic activity in cultured human vascular SMC more effectively than in IGF-1-induced mitotic activity, but at 10(-5) M, the inhibitory effects were similar. Diltiazem also showed a clear inhibition of migration ability, both under basal conditions (p < 0.05) and after addition of insulin (p = 0.0001) and IGF-1 (p < 0.0001). Finally, diltiazem inhibited membrane ruffling induced both by insulin and IGF-1 in a similar manner, and similar results were obtained with SMC from rat aorta. We conclude that substances blocking the L-type calcium channels such as diltiazem, could inhibit those processes which in vivo lead SMC to form the atheroma plaque.

Actins↗
PubMed2002

Apoptosis and CD8 and CD54 cell expression in rat small bowel transplantation.

The importance of activated CD8 cells expressing IL-2R in small bowel and other organ rejection has been reported. Some authors even consider that a positive correlation might be demonstrated between the number of apoptotic enterocytes and the degree of graft rejection. In addition, moderate to intense activation of endothelial molecules in small bowel allograft in rats has been reported in chronic rejection. The aim of the present paper is to ascertain, in a heterotopic small bowel transplantation (HSBT) in rats, whether CD3, CD4, CD8, and CD54 cell expression in the allograft infiltrates shows some relationship with allograft enterocyte apoptosis when rejection is present. Wistar Furth male rats were allotted to two groups: group A was the control group without transplantation; group B received a heterotopic small bowel allograft from Fisher rats and an im dose of FK506 (0.25 mg/kg/day). A significant increase of CD8, CD54 cell receptor expression, and apoptosis in the group undergoing HSBT showed rejection. No significant differences have been observed in the variables under study between the control and HSBT without rejection groups or in CD3 and CD4 among the three groups. We observed a significant correlation between apoptosis and rejection, between CD8 and CD54 with apoptosis and with rejection, and between CD8 and CD54. This indicates that the activation of endothelial molecules and cells may play an important role in established HSBT chronic rejection. We consider that this study may contribute to the knowledge of small bowel allograft chronic rejection and its immunomodulation.

Animals↗
PubMed2002

CDP-choline reduces pro-caspase and cleaved caspase-3 expression, nuclear DNA fragmentation, and specific PARP-cleaved products of caspase activation following middle cerebral artery occlusion in the rat.

Citicoline has been demonstrated to be beneficial in several models of cerebral ischaemia. We tested the hypothesis that citicoline may provide apoptotic pathways following focal cerebral ischaemia. Focal cerebral ischaemia was produced by distal, permanent middle cerebral artery occlusion (MCAO) in Sprague-Dawley rats. The animals were randomised into four groups: (B+A) Citicoline 500 mg/kg IP 24 and 1 h before MCAO, and 23 h after MCAO; (A) citicoline 500 mg/kg IP, within 30 min after MCAO, and 23 h after MCAO; (C) vehicle IP; and (D) sham-operated. The animals were sacrificed at 12 h (n=8 per group) and 24 h (n=8 per group) after MCAO. Immunohistochemistry was performed on free-floating tissue sections with goat polyclonal antibodies to procaspase-1, -2, -3, -6 and -8, and in paraffin-embedded sections processed for cleaved caspase-3 (17 kDa) immunohistochemistry. Finally, some sections were stained with the method of in situ end-labelling of nuclear DNA fragmentation. For gel electrophoresis and Western blotting, antibodies to poly (ADP-ribose) polymerase (PARP) products of 89 kDa were used to reveal specific cleavage substrates of caspases. MCAO induced the expression of all procaspases and the expression of PARP products of 89 kDa, as well as cells with nuclear DNA fragmentation, at 12 and 24 h, in the infarcted core and penumbra. Citicoline reduced the expression of all procaspases at 12 and 24 h after MCAO, as well as the expression of cleaved caspase-3 in cells in the penumbra area. This was accompanied by a reduction in the number of cells bearing nuclear DNA fragments. The expression of caspase-cleaved products of PARP (PARP 89 kDa) was reduced in citicoline-treated ischaemic rats. These results show that citicoline inhibits the expression of proteins involved in apoptosis following MCAO.

Animals↗
PubMed2001

Determination of the immunoglobulin E postoperative variation as a measure of surgical injury.

The aim of this study was to ascertain postoperative changes in immunoglobulin E (IgE) in patients undergoing different types of surgery and the possible correlation with the duration and type of surgery. Evidence suggests that surgery induces a predominant activation pattern through the T-helper-2 (Th2) cell pathway, increasing interleukins (IL-4, IL-5, IL-10, IL-13), inhibiting Th1 cell activation, and promoting B and Th2 cell activation. IgE production may indicate predominant Th2 pathway activation and may be a more persistent and easily measurable postoperative marker than IL-6 for measuring surgical trauma. Altogether, 180 patients undergoing different types of surgery for nonneoplastic and nonparasitic diseases were studied. All patients received the same type of anesthesia. Before surgery and on the first (1PO) and 7th (7PO) postoperative days we determined in peripheral blood the CD3, CD4, CD8, CD16, and CD19 cell percentages; IL-1, IL-2, IL-4, IL-6, and tumor necrosis factor (TNF) levels; and the IgA, IgG, IgM, total IgE, C3, C4, and CIC levels. On 1PO, all variables decreased except IgE, IL-1, IL-2, IL-4, IL-6, CIC, and CD19. Only IgE, IL-6, and CD19 increases showed a significantly statistical (ss) difference regarding preoperative values (0.01, 0.05, 0.001, respectively). Relations between the IL-4 and IgE increases (p < 0.01) and between the IgG decrease and IgE increase (p < 0.001) were found. On 7PO, only IgE was increased (p < 0.001). The IgE increase correlated with surgical trauma intensity (p < 0.05). We concluded that IgE increases during the early postoperative period, correlating with surgical injury intensity. The increase in the IgE level may be detected 24 hours after surgery and during the first 7 postoperative days depending on the type of surgery.

Adult↗
PubMed2001

Therapeutic response to octreotide in patients with refractory CPT-11 induced diarrhea.

PURPOSE: Severe diarrhea can represent a dose-limiting toxicity with the use of CPT-11. Conventional therapy is ineffective in some patients and is also limited by patient compliance. We report our observation on the effectiveness of octreotide acetate in the treatment of CPT-11-induced diarrhea refractory to opioids. PATIENTS AND METHODS: We describe 4 patients with metastatic gastrointestinal tumors who developed severe diarrhea following treatment with CPT-11 (65-125 mg/m2/weekly for 4 weeks every 6 weeks). Diarrhea was refractory to treatment with loperamide and diphenoxylate and was treated with octreotide acetate. RESULTS: Complete resolution of diarrhea was observed within 2-4 days of octreotide acetate treatment. Three patients responded to SC octreotide given every 8 hours and the 4th patient to octreotide given by continuous s.c. infusion. CONCLUSIONS: Our preliminary observation suggests value of octreotide in the control of CPT-11 induced refractory diarrhea. Prospective studies are warranted.

Adult↗
PubMed2001

N-terminal fatty acid substitution increases the leishmanicidal activity of CA(1-7)M(2-9), a cecropin-melittin hybrid peptide.

In order to improve the leishmanicidal activity of the synthetic cecropin A-melittin hybrid peptide CA(1-7)M(2-9) (KWKLFKKIGAVLKVL-NH(2)), a systematic study of its acylation with saturated linear fatty acids was carried out. Acylation of the N(epsilon)-7 lysine residue led to a drastic decrease in leishmanicidal activity, whereas acylation at lysine 1, in either the alpha or the epsilon NH(2) group, increased up to 3 times the activity of the peptide against promastigotes and increased up to 15 times the activity of the peptide against amastigotes. Leishmanicidal activity increased with the length of the fatty acid chain, reaching a maximum for the lauroyl analogue (12 carbons). According to the fast kinetics, dissipation of membrane potential, and parasite membrane permeability to the nucleic acid binding probe SYTOX green, the lethal mechanism was directly related to plasma membrane permeabilization.

Acylation↗
PubMed2000

Characterization of the potato MADS-box gene STMADS16 and expression analysis in tobacco transgenic plants.

A new MADS-box gene, STMADS16, has been cloned in Solanum tuberosum L. that is expressed in all vegetative tissues of the plant, mainly in the stem, but not in flower organs. STMADS16 expression is established early during vegetative development and is not regulated by light. Sequence similarity besides the spatial and temporal expression patterns allow to define a novel MADS-box subfamily comprising STMADS16 and the gene STMADS11. Expression of the STMADS16 sense cDNA under the control of the 35S cauliflower mosaic virus promoter modifies the inflorescence structure by increasing both internode length and flower proliferation of the inflorescence meristems, and confers vegetative features to the flower. Moreover, STMADS16 ectopic expression overcomes the increase in flowering time and node number produced under short-day photoperiod, while the flowering time is not affected in long-day conditions. These results are discussed in terms of a possible role for STMADS16 in promoting vegetative development.

Amino Acid Sequence↗
PubMed2000

The global burden of injuries.

The traditional view of injuries as "accidents", or random events, has resulted in the historical neglect of this area of public health. However, the most recent estimates show that injuries are among the leading causes of death and disability in the world. They affect all populations, regardless of age, sex, income, or geographic region. In 1998, about 5.8 million people (97.9 per 100,000 population) died of injuries worldwide, and injuries caused 16% of the global burden of disease. Road traffic injuries are the 10th leading cause of death and the 9th leading cause of the burden of disease; self-inflicted injuries, falls, and interpersonal violence follow closely. Injuries affect mostly young people, often causing long-term disability. Decreasing the burden of injuries is among the main challenges for public health in the next century--injuries are preventable, and many effective strategies are available. Public health officials must gain a better understanding of the magnitude and characteristics of the problem, contribute to the development and evaluation of injury prevention programs, and develop the best possible prehospital and hospital care and rehabilitation for injured persons.

Adolescent↗
PubMed2000

Autologous blood transfusion as an immunomodulator in experimental sepsis.

BACKGROUND: Homologous blood transfusion is associated with immunosuppressive consequences. Some clinical and experimental studies have suggested an immunostimulating action of autologous blood transfusion. The aim of this paper is to ascertain the effects of either homologous blood transfusion or autologous blood transfusion on the lymphocyte subsets and cytokines in a model of intra-abdominal sepsis. MATERIALS AND METHODS: There were three study groups. Group A: 10 Wistar-Furth (WF) rats underwent cecal ligation and puncture (CLP) aimed at causing an intra-abdomial sepsis; Group B: 10 WF rats underwent CLP plus 1 ml homologous blood perioperative transfusion obtained from Fisher-344 rat while Group C: 10 WF rats underwent CLP plus 1 ml autologous blood perioperative transfusion. Changes of peripheral lymphocyte subsets, percentages of total T-lymphocytes (CD3), Helper T-lymphocytes (CD4), supressor/cytotoxic T-lymphocytes (CD8), CD4/CD8 ratio, Interleukin-2 receptor expression (IL-2R) and cytokines IL-1 and TNF-alpha were measured in peripheral blood on the preoperative, 1st, 3rd and 7th postsepsis (PO) days. RESULTS: Rats in homologous transfused group showed a decrease of %CD4 on the 3rd PO (from preoperative to 3rd PO;p < 0.01; and from 1st to 3rd PO; p < 0.05) and on the 7th PO (from preoperative to 7th PO; p < 0.05); %CD8 increased from preoperative to 3rd PO (p < 0.05), from 1st to 3rd PO (p < 0.01) and from 1st to 7th PO (p < 0.05). An initial decrease on day 1 (p < 0.01) followed by an increase on the 3rd PO (p < 0.01) with regard to IL-2R and a significant increase of IL-1 levels within the first 24h (p < 0.01). Rats in autologous transfused group showed an increase of %CD3 from preoperative to 7th PO (p < 0.05), and from 3rd to 7th PO (p < 0.01). CONCLUSIONS: We observed that homologous blood transfusions induce a greater alteration in the cellular immune response and of the cascade of cytokines than autologous transfusions. This modulates the variations of the immune response induced by sepsis.

Animals↗
PubMed2000

S-adenosylmethionine immunomodulator treatment in sepsis.

BACKGROUND: S-adenosylmethionine (SAMe) is a forerunner of glutathione. AIMS: The aim of the present study is to ascertain this drug effect on T-lymphocytes and cytokines in an experimental model of surgical sepsis. METHODS: Rats were allotted in two groups. In the control group, rats underwent anaesthesia and laparatomy with cecal ligation and puncture (CLP). In the second group, rats underwent the same CLP and received SAMe (14 mg/kg) i.m., on the 1st (1PO) and 2nd (2PO) postoperative days. A week before surgery (PRE), on the 1PO and on the 3PO: IL-1, IL-2, IL-4, IL-6, IL-10 and TNF levels (ELISA & MoAb), and CD3, CD4, CD8 cell and IL-2R percentages (%) (flow cytometry & MoAb) were determined in peripheral blood. RESULTS: Rats receiving SAMe do not show changes of CD3%, CD4% and IL-1 levels but show a significant increase of CD8% on the 3PO, showing a significant difference with regard to controls (p < 0.01). Both groups show a similar IL-2R variation pattern: increasing on 1PO (p < 0.05) and decreasing on 3PO (p < 0.05). CONCLUSION: In sepsis: SAMe inhibits the decrease of circulating immune-active cells and the IL-1 increase. This drug seems to have effects useful in avoiding immunological alterations in sepsis, that need to be tested in humans.

Adjuvants, Immunologic↗
PubMed1999

Stamenless, a tomato mutant with homeotic conversions in petals and stamens.

A tomato (Lycopersicon esculentum Mill.) monogenic semidominant mutation, stamenless (sl), which results in homeotic conversions in two adjacent floral whorls, was studied. When grown at standard temperature, flowers of sl/sl plants showed sepaloid petals in the second whorl and strong transformation of stamens to carpels in whorl three. These transformed carpels were fused with each other and with the genuine carpels in the fourth whorl to form a unique gynoecium. The mutation is semidominant since heterozygous plants showed a phenotype intermediate between that of the wild type (WT) and that of homozygous mutant plants, with nearly WT petals but with feminized stamens bearing naked ovules on the base of their adaxial face. The initiation and position of organ primordia in sl/sl flowers were not altered when compared with WT primordia although development of organ primordia in the second and third whorls deviated from WT at an early stage as observed by scanning electron microscopy. The mutant phenotype is temperature sensitive and when sl/sl plants were cultured at low temperature, the morphology of some flowers resembled that of the WT. This reversion of the mutant phenotype is also induced by treatment of young sl/sl plants with gibberellic acid, providing evidence that gibberellin synthesis or sensitivity could mediate the effect of low temperature on the mutant phenotype. Southern blot analyses using a Deficiens-homologous gene from Solanum tuberosum as a probe showed a restriction-fragment-length polymorphism (RFLP) linked to the sl mutation. This result indicates that the mutation affects a Deficiens-like gene that controls the identity of petals and stamens.

Journal Article↗
PubMed1999

Evolution of centromeric satellite DNA and its use in phylogenetic studies of the Sparidae family (Pisces, Perciformes).

In this paper, we use the EcoRI centromeric satellite DNA family conserved in Sparidae as a taxonomic and a phylogenetic marker. The analyses of 56 monomeric units (187 bp in size) obtained by means of cloning and PCR from 10 sparid species indicate that this repetitive DNA evolves by concerted evolution. Different phylogenetic inference methods, such as neighbor-joining and UPGMA, group the 56 repeats by taxonomic affinity and support the existence of at least two monophyletic groups within the Sparidae family. These results reinforce the recent taxonomic revision of the genera Sparus and Pagrus and contradict previous classifications of the Sparidae family.

Animals↗
PubMed1999

A randomized blinded clinical trial of two antivenoms, prepared by caprylic acid or ammonium sulphate fractionation of IgG, in Bothrops and Porthidium snake bites in Colombia: correlation between safety and biochemical characteristics of antivenoms.

A randomized blinded clinical trial was performed in 53 patients bitten by Bothrops sp. and Porthidium sp. in Antioquia and Chocó, Colombia, in order to compare the efficacy and safety of two antivenoms made of whole IgG obtained by either ammonium sulphate (monovalent anti-B. atrox) or caprylic acid (polyvalent) fractionation. Additionally, antivenoms were compared by electrophoretic and chromatographic analyses and anticomplementary activity in vitro. With a protocol of 2, 4 and 6 antivenom vials for the treatment of mild, moderate and severe envenomings, respectively, both antivenoms were equally efficient to neutralize the most relevant signs of envenoming and to clear serum venom levels in patients from the first hour and later on. Three patients with severe envenoming and initially treated with less than six vials on admission had persistent or recurrent venom antigenemia within 12-48 h. Monovalent antivenom fractionated by ammonium sulphate precipitation had higher amounts of protein aggregates and nonimmunoglobulin proteins than polyvalent antivenom fractionated by caprylic acid precipitation. Both antivenoms presented anticomplementary activity in vitro, being higher in the monovalent product. In agreement, monovalent antivenom induced a significantly higher incidence of early antivenom reactions (52%) than polyvalent antivenom (25%).

Adolescent↗