Search PubMed⌕ Search

Biomedical subjects

E Ruiz

Publications and source records attributed to E Ruiz.

At least 19 recordsLinked to original sources
PubMed2004

Decrease of parafollicular thyroid C-cells in experimental esophageal atresia: further evidence of a neural crest pathogenic pathway.

Adriamycin-induced experimental esophageal atresia (EA) is often associated with malformations of neural crest (NC) origin, such as abnormal pharyngeal pouch derivatives like the thymus and the parathyroids. The aim of the present study was to examine whether NC-derived thyroid C-cells were abnormal in a rat model. Pregnant rats received intraperitoneally either 2 mg/kg Adriamycin (EA) or vehicle (controls) on days 8 and 9 of gestation. Fetuses were recovered on day 21, and blocks including the trachea and thyroid were fixed in formalin, coronally sectioned at 3-mum widths, and stained with standard hematoxylin and eosin until the largest area of thyroid was reached. From this point on, the 1st, 10th, and 20th slices were immunohistochemically stained with anti-calcitonin antibody. Positively-stained cells in each section of the gland were counted using a computer-assisted image analysis method, and the results were averaged. The distribution of the cells within the gland was assessed as well. Comparisons between EA and control rats were made by nonparametric tests with a significance threshold of p<0.05. The number of C-cells was dramatically reduced in EA animals compared with controls (32.4+/-36 vs. 92.3+/-60.5, p<0.001). Histology of the thyroid was similar in both groups, but the distribution of positive C-cells within the gland followed an abnormal pattern in EA rats. Adriamycin causes a pattern of NC-derived malformations, including a severe decrease in thyroid C-cells accompanied by abnormal distribution or migration patterns. These results represent further evidence of the involvement of NC organogenic control dysregulation in the pathogenesis of EA and its associated malformations. The similarities between the rat model and the clinical picture strongly support investigating other subclinical NC-derived anomalies in patients with EA.

Animals↗
PubMed2004

Creation of BAC genomic resources for cocoa ( Theobroma cacao L.) for physical mapping of RGA containing BAC clones.

We have constructed and validated the first cocoa ( Theobroma cacao L.) BAC library, with the aim of developing molecular resources to study the structure and evolution of the genome of this perennial crop. This library contains 36,864 clones with an average insert size of 120 kb, representing approximately ten haploid genome equivalents. It was constructed from the genotype Scavina-6 (Sca-6), a Forastero clone highly resistant to cocoa pathogens and a parent of existing mapping populations. Validation of the BAC library was carried out with a set of 13 genetically-anchored single copy and one duplicated markers. An average of nine BAC clones per probe was identified, giving an initial experimental estimation of the genome coverage represented in the library. Screening of the library with a set of resistance gene analogues (RGAs), previously mapped in cocoa and co-localizing with QTL for resistance to Phytophthora traits, confirmed at the physical level the tight clustering of RGAs in the cocoa genome and provided the first insights into the relationships between genetic and physical distances in the cocoa genome. This library represents an available BAC resource for structural genomic studies or map-based cloning of genes corresponding to important QTLs for agronomic traits such as resistance genes to major cocoa pathogens like Phytophthora spp ( palmivora and megakarya), Crinipellis perniciosa and Moniliophthora roreri.

Cacao↗
PubMed2003

Relation between leptin and body fat distribution in menopausal status.

We examined the serum concentrations of leptin in a homogeneous group of 52 postmenopausal Mediterranean women, calculating body fat mass distribution by waist-to-hip circumference ratio (WHR) and other anthropometric measurements. Significant correlations were found between leptin and weight (r=0.59), Body Mass Index (BMI) (r=0.56), Conicity Index (CI) (r=0.49) and all circumferences measured: chest (r=0.55), waist (0.61) and hip (r=0.65), but not between leptin and WHR. Leptin levels does not seem to be influenced by fat mass distribution (android or gynoid type) while weight gain over life appears to be related with the hormone concentration when menopausal status is well established.

Adipose Tissue↗
PubMed2003

Rickettsia typhi infection in wild rodents from central Spain.

When sera from 218 rodents captured in two provinces of central Spain were tested, by indirect immunofluorescence, for antibodies to Rickettsia typhi, 46 (21.1%) were found to be positive, at titres between 1:20 and 1:320. The seropositives included rodents of each of the five species collected: Mus musculus, Mus spretus, Apodemus sylvaticus, Rattus rattus and Rattus norvegicus. Rickettsia typhi infection appears to be common and widespread among the rodents of central Spain.

Animals↗
PubMed2002

Protein nitration in cutaneous inflammation in the rat: essential role of inducible nitric oxide synthase and polymorphonuclear leukocytes.

1: We have examined the relationship between neutrophil accumulation, NO(*) production and nitrated protein levels in zymosan-mediated inflammation in rat skin in vivo. 2: Rats were anaesthetized and cutaneous inflammation was induced by zymosan (injected intradermally, i.d.). Experiments were carried out up to 48 h, in recovery procedures as appropriate. Assays for neutrophil accumulation (measurement of myeloperoxidase), nitric oxide (assessment of NO(2)(-)/NO(3)(-)) and nitrated proteins (detected by ELISA and Western blot) were performed in skin extracts. 3: The results demonstrate a close temporal relationship between these parameters. Samples were assayed at 1, 4, 8, 24 and 48 h after i.d. injection of zymosan. The highest levels measured of each parameter (P<0.001 compared with vehicle) were found at 4-8 h, with a reduction towards basal levels by 24 h. 4: Selective depletion of circulating neutrophils with anti-neutrophil antibody abolished neutrophil accumulation and protein nitration. In addition substantially decreased NO levels were found. 5: A selective inducible nitric oxide synthase (iNOS) inhibitor, N-3-aminomethyl-benzyl-acetamidine-dihydrochloride (1400W) also significantly reduced neutrophil levels and NO production and substantially inhibited protein nitration. 6: We conclude that the neutrophil leukocyte plays an essential role in the formation of iNOS-derived NO and nitrated proteins in inflammation, in a time-dependent and reversible manner. The NO-derived iNOS also has a role in stimulating further neutrophil accumulation into skin. This suggests a close mechanistic coupling between neutrophils, NO production and protein nitration.

Analysis of Variance↗
PubMed2002

Physiological and performance responses to a 6-day taper in middle-distance runners: influence of training frequency.

The purpose of this investigation was to examine the influence of training frequency on performance and some physiological responses during a 6-day taper. After 18 weeks of training, 9 male middle-distance runners were assigned to a high frequency taper (HFT, n = 5) or a moderate frequency taper (MFT, n = 4), consisting of training daily or resting every third day of the taper. Taper consisted of an 80% nonlinear progressive reduction in high intensity interval training. Blood samples were obtained, and 800 m performance and peak blood lactate ([La] peak ) measured before and after taper. Performance improved significantly after HFT (121.8 +/- 4.7 vs 124.2 +/- 4.9 s, p < 0.05), but not after MFT (126.6 +/- 2.8 vs 127.1 +/- 2.1 s). Neutrophils (2.89 +/- 0.68 vs 2.56 +/- 0.61 10 (3) x mm(-3)), granulocytes (3.08 +/- 0.70 vs 2.77 +/- 0.66 10 (3) x mm(-3)), haptoglobin (79.7 +/- 47.9 vs 60.7 +/- 33.6 mg x dl(-1)), total testosterone (7.39 +/- 1.67 vs 5.52 +/- 0.88 microg x l(-1)) and [La] peak (15.5 +/- 1.5 vs 14.4 +/- 2.0 mmol x l(-1)) significantly increased with taper. [La] peak correlated with performance time before taper (r = -0.76, p < 0.05), and change in [La] peak with change in serum cortisol (r = -0.75, p < 0.05) and total testosterone:cortisol ratio (r = 0.82, p < 0.01). In conclusion, training daily during a 6-day taper brought about significant performance gains, whereas resting every third day did not. High [La] peak and a hormonal milieu propitious to anabolic processes seemed to be necessary for optimum performance.

Adult↗
PubMed2002

Pleural-fluid myeloperoxidase in complicated and noncomplicated parapneumonic pleural effusions.

The diagnostic accuracy of myeloperoxidase (MPO) in pleural fluid, for differentiating between complicated and noncomplicated parapneumonic pleural effusions (PPE) evaluated prospectively. Seventy patients aged >18 yrs with PPE (36 complicated and 34 noncomplicated) were studied after admission to a tertiary referral teaching hospital. MPO concentration was measured in plasma and pleural fluid using a double-antibody competitive radioimmunoassay. The concentrations of MPO in complicated and noncomplicated PPE were compared using a Mann-Whitney U-test and multiple logistic regression models were used to predict the odds that an effusion was complicated. MPO pleural-fluid concentrations were significantly higher in complicated than in noncomplicated PPE. After excluding purulent effusions, pleural-fluid MPO was the marker that best differentiated between the two types of PPE: the area under the receiver operating characteristic curve was 0.912, the sensitivity was 87.5% and the specificity was 85.1% at a cut-point limit of 3.000 microg x L(-1). The authors concluded that the concentration of pleural-fluid myeloperoxidase helps to differentiate between nonpurulent complicated and noncomplicated parapneumonic pleural effusions.

Biomarkers↗
PubMed2002

[Repercussion of age on management of neoplastic patients in an Internal Medicine Service].

AIM: To determine whether age is a factor affecting the management of patients diagnosed with neoplastic disease in an internal medicine service. PATIENTS AND METHODS: Prospective study of 388 patients diagnosed with cancer in the internal medicine service of a large public health teaching hospital. We evaluated clinical characteristics, diagnostic procedures, types and stage of neoplasm, referral after hospital discharge and treatment. A comparative study based on age was performed between patients 65 years older and patients under this age. RESULTS: The 388 cancer patients accounted for 12% of hospital admissions in our service. Among the total, 62% were > or = 65 years old. Constitutional syndrome, the most frequently associated symptom and the main reason for the consultation, was more common in the > or = 65-year-old group. Lung cancer was predominant in men and hematologic neoplasms in women. Patients > or = 65 were referred more frequently to internal medicine physicians, general practitioners and home palliative assistance services (p < 0.05) and they received only palliative treatment in a greater percentage of cases (50% vs. 37%, p = 0.001). CONCLUSIONS: The incidence of neoplasms in our service was high (12%), with a considerable percentage of patients in advanced phases of the disease (83%). Age was not related to diagnostic methods nor was it determinant in the staging, but it did have repercussions on treatment; patients > or = 65 received palliative treatment alone more often than younger patients.

Adult↗
PubMed2001

Exchange coupling in cyano-bridged homodinuclear Cu(II) and Ni(II) complexes: synthesis, structure, magnetism, and density functional theoretical study.

The synthesis and structural characterization of several new cyano-bridged copper(II) and nickel(II) homodinuclear complexes is presented. The measure of magnetic properties for these complexes is complemented with a computational study of the exchange coupling for several model structures representing this family of compounds. The influence of several factors on the coupling constant has been examined, coordination position occupied by the bridging ligand, distortions of the coordination environment, and relative disposition of the cyanide ion with respect to the M-M vector. Comparison of experimental and calculated coupling constants allows for the rationalization of the most relevant features of the exchange interaction between two identical metal ions through a cyano bridge.

Journal Article↗
PubMed2001

[Tumors diagnosed in 65 patients with type I neurofibromatosis].

BACKGROUND: Type 1 neurofibromatosis patients develop malignant neoplasm more frequently than general population. PATIENTS AND METHOD: We have studied 65 patients with neurofibromatosis type 1 because we intend to know the kind of neoplasms that they have presented. RESULTS: 65 patients (48 men and 17 women) fulfilling type 1 neurofibromatosis criteria have been studied. Globally 67 tumors appeared, from which 47 (70%) were benign and 20 (30%) were malignant. Benign tumors included 25 neurofibromas, 11 central nervous system tumors and 11 extraneurological tumors. Malignant tumors accounted for 6 soft tissue sarcomas, 6 carcinomas, 3 malignant CNS tumors and 2 acute lymphoblastic leukemias. CONCLUSION: Presentation of neoplasms is frequent in type 1 neurofibromatosis and constitutes main death and morbility cause.

Aged↗
PubMed2001

Growth inhibitory activity of indapamide on vascular smooth muscle cells.

Abnormal vascular smooth muscle cell proliferation has a fundamental role in the pathogenesis of vascular diseases. Indapamide is an oral diuretic antihypertensive drug effective for patients with mild or moderate essential hypertension. We now investigated the effects of indapamide on the growth of aortic vascular smooth muscle cells (A10 cell line). Indapamide inhibited cell proliferation as measured by the tetrazolium salt XTT (sodium 3'-[1-(phenylamino-carbonyl)-3,4-tetrazolium]-bis(4-methoxy-6-nitro)benzene sulfonic acid hydrate) test. The increase in cell number was significantly reduced in the presence of indapamide 10(-6) and 5 x 10(-4) M (P < 0.05 n = 3 and P < 0.01, n = 3, respectively). Serum-induced DNA synthesis, determined as the incorporation of 5-bromo-2'-deoxyuridine (BrdU), was concentration-dependently inhibited by indapamide. BrdU incorporation was 47.2+/-1.6% (10% foetal calf serum). Indapamide treatment markedly prevented BrdU incorporation (37.2+/-2.1%, 29.2+/-4.8%, 15.0+/-1.8%, 8.7+/-2.1%) indapamide 10(-6), 10(-5), 5 x 10(-5) and 5 x 10(-4) M, respectively. Cell-cycle progression was also evaluated. Flow cytometry analysis of DNA content in synchronised cells revealed blocking of the serum-inducible cell-cycle progression by indapamide. This inhibition was abolished when the drug was added 2 h after serum repletion, indicating that indapamide must act at the early events of a cell cycle to be fully effective against DNA synthesis. In addition, serum-induced intracellular Ca2+ movements and also p44/p42 mitogen-activated protein kinase (MAPK) phosphorylation were studied in the presence or absence of indapamide. Indapamide 10(-5) and 5 x 10(-5) M decreased significantly cytosolic free calcium, and the p44/p42 mitogen-activated protein kinase phosphorylation (5 x 10(-5) M) stimulated by 10% foetal calf serum. In accordance with this finding, indapamide (5 x 10(-4) M) caused a 95% to 99% decrease in the early elevation of c-fos expression as evaluated by northern blot analysis of mRNA induced after serum addition. In conclusion, our results indicate that indapamide reduces vascular smooth muscle cell proliferation by a mechanism which involves a decrease in the intracellular Ca2+ movements that might link with the mitogen-activated protein kinase (MAPK) pathway, altering cell-cycle progression.

Animals↗
PubMed2001

Copper(II) complexes with 4-amino-N-[4,6-dimethyl-2-pyrimidinyl]benzenesulfonamide. Synthesis, crystal structure, magnetic properties, EPR, and theoretical studies of a novel mixed mu-carboxylato, NCN-bridged dinuclear copper compound.

New Cu(II) complexes of sulfamethazine (4-amino-N-[4,6-dimethyl-2-pyrimidinyl]benzenesulfonamide, HL) [Cu(2)(CH(3)COO)(2)(L)(2)].2dmf (1) and ([Cu(L)(2)].2H(2)O)(infinity) (2) were prepared and structurally characterized. Compound 1 crystallizes in the monoclinic system, space group P2(1)/n, with a = 8.9486(9) A, b = 15.0956(12) A, c = 16.542(3) A, beta = 105.584(15) degrees, and Z = 2. Compound 2 crystallizes in the monoclinic system, space group P2(1)/c, with a = 13.8097(8) A, b = 14.5765(4) A, c = 13.7853(15) A, beta = 96.033(9) degrees, and Z = 1. In compound 1 two copper ions are linked by two syn-syn acetates and two nonlinear NCN bridging groups pertaining to the deprotonated sulfamethazine ligands. Each copper center presents a nearly square planar geometry. Magnetic susceptibility data for 1 show a strong antiferromagnetic coupling with 2J = -216.7 cm(-)(1). The EPR spectra at the X- and Q-band frequencies present the signals corresponding to the dinuclear entity, being the zero-field splitting parameter, D = 0.265 cm(-)(1). The antiferromagnetic exchange coupling is discussed using DFT calculations on some model compounds with NCN bridging ligands and also on model structures with mixed mu-acetato and NCN bridges. The copper in the polymeric compound 2 is five coordinate. The CuN(5) chromophore has a highly distorted square pyramidal geometry with small axial N-Cu-N angles of 65.53(14) and 59.90(13) degrees. In the structure a sulfamethazinate anion binds to one copper through the sulfonamido and pyrimidine N atoms and to an adjacent copper via the amino N atom.

Journal Article↗
PubMed2001

Exchange coupling in carboxylato-bridged dinuclear copper(II) compounds: a density functional study.

A computational study of the exchange coupling is presented for a selected sample of carboxylato-bridged dinuclear copper(II) compounds. Model calculations have been used to examine the influence of several factors on the coupling constants: a) the electron-withdrawing power of the bridging ligands; b) the nature of the axial ligands; c) the number of bridging carboxylato groups; d) some structural distortions frequently found in this family of compounds; and e) the coordination mode of the carboxylato bridge. Coupling constants calculated for some complete structures, as determined by X-ray diffraction, are in excellent agreement with experimental data, confirming the ability of the computational strategy used in this work to predict the coupling constant for compounds for which experimental data are not yet available.

Journal Article↗
PubMed2001

Sigmoid cystoplasty with argon beam without mucosa.

PURPOSE: Intestinal bladder augmentations have well recognized complications, including mucus production, metabolic abnormalities and perforation. These complications may be avoided if the intestinal mucosa is not incorporated in the urinary tract. We report our experience with sigmoid cystoplasty without mucosa using argon beam, and describe the clinical, urodynamic, ultrasound and pathological results. MATERIALS AND METHODS: We performed sigmoid cystoplasty without mucosa in 26 patients and with argon beam over the mucosa before it was removed in 6 boys and 4 girls with a mean age of 8 years (range 3 to 14). All patients had neurogenic bladder as the initial disease. Indications for augmentation were poor bladder compliance, low bladder capacity, hydronephrosis and urinary incontinence. Mean followup was 18 months (range 8 to 40) and included ultrasound, urodynamic evaluation, renal function and clinical assessment. In all patients intraoperative biopsies were done. In 8 of the 10 patients endoscopic biopsies of the augmented segment were obtained between 6 months and 2 years postoperatively. The operation consisted of the Goodwin technique without mucosa, which was treated with argon beam before it was removed. RESULTS: The 10 patients are dry on intermittent clean catheterization with intervals of greater than 4 hours. There have been no clinical urinary tract infections. Two patients presented with peristaltic contractions and no symptoms. Bladder capacity increased from 80 (range 45 to 200) to 300 (220 to 400) ml., and mean postoperative compliance was 15 ml./cm. H2O (range 9 to 38). There were no significant changes in the urodynamic data between patients treated with sigmoid cystoplasty without mucosa only and with argon beam. Intraoperative biopsies after treatment with argon beam showed damaged mucosa and muscularis mucosa, and intact serosa, muscularis and submucosa layers. On the 8 argon beam postoperative biopsies the sigmoid submucosa was covered with a pseudostratified metaplasia of connective tissue with collagen fibers without scars (trichromic technique). CONCLUSIONS: Sigmoid cystoplasty without mucosa with argon beam is easy to perform. The clinical and urodynamic results have been satisfactory, and use of argon beam prevents postoperative bleeding and residual glands.

Adolescent↗
PubMed2001

Single distal ureter for ureterocystoplasty: a safe first choice tissue for bladder augmentation.

PURPOSE: Recently, the use of ureter for bladder augmentation has gained wide acceptance due to a lower complication rate compared to gastrointestinal segments. Unfortunately, the presence of a severely dilated urinary tract implicates loss of function of a renal unit which is often not demonstrated at diagnosis. Conversely, many patients present with 1 or both ureters mildly dilated because of vesicoureteral reflux or functional obstruction. In these cases the use of a single distal ureter seems to be a good option. We report our experience and long-term followup with this subset of patients. MATERIALS AND METHODS: Between December 1994 and November 1998, 17 females and 5 males 1.5 to 15.7 years old (mean age 7.2) with a low capacity, poorly compliant bladder underwent ureterocystoplasty with a single distal dilated ureter. Diagnosis included myelomeningocele in 13 cases, central neurogenic bladder in 3, neurogenic nonneurogenic bladder in 2, congenital spinal cord injury in 2, sacral agenesis in 1 and giant sacral teratoma in 1. All but 2 patients complained of recurrent febrile urinary tract infections. Variable degrees of hydronephrosis were observed in all patients. Vesicoureteral reflux was detected in 14 patients and was bilateral in 3. Five patients presented with chronic renal failure. Before surgery 19 patients were on clean intermittent catheterization and prophylactic antibiotics. The segments of ureter used for augmentation ranged from 9 to 14 cm. long (mean 11) and from 0.8 to 2.5 cm. in diameter (mean 1.3). The more distal piece of the ureter was kept unopened to preserve vascular supply. Simultaneous procedures included transureteroureterostomy in all 22 patients, appendicovesicostomy in 10, bladder neck continence procedures in 4 and ureteroneocystostomy in 3. Clinical, radiological and urodynamic evaluation was done 6 months postoperatively and yearly thereafter. RESULTS: Followup ranged from 12 to 60 months (mean 22). Of the patients 19 are dry on clean intermittent catheterization at 4-hour intervals and 6 have had 9 symptomatic urinary tract infections. Hydronephrosis resolved in 14 patients, improved in 6 and remained unchanged in 2. On urodynamics median increase in capacity less than 30 cm. pressure was 177% (range 11% to 560%). When comparing capacity less than 30 cm. water to normal expected capacity for age and weight, 50% of the cases reached or exceeded theoretical capacity while the rest reached 63% to 89% (mean 76%). Long-term complications included persistent reflux in 1 case, deterioration of bladder function without clinical impairment in 1 and spontaneous perforation of the ureteral patch in 1 requiring colocystoplasty. CONCLUSIONS: Although increase in bladder capacity is not always optimal with the use of a distal dilated ureter, it is good enough to ensure a good clinical outcome and allow an adequate catheterization interval with a low complication rate in the long term, thus avoiding use of a piece of gut or stomach to perform bladder augmentation in nearly all patients.

Adolescent↗