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Biomedical subjects

I Martínez

Publications and source records attributed to I Martínez.

At least 19 recordsLinked to original sources

New Neandertal remains from Cova Negra (Valencia, Spain).

New Neandertal fossils from the Mousterian site of Cova Negra in the Valencia region of Spain are described, and a comprehensive study of the entire human fossil sample is provided. The new specimens significantly augment the sample of human remains from this site and make Cova Negra one of the richest human paleontological sites on the Iberian Peninsula. The new specimens include cranial and postcranial elements from immature individuals and provide an opportunity to study the ontogenetic appearance of adult Neandertal characteristics in this Pleistocene population. Children younger than 10 years of age constitute four of the seven minimum number of individuals in the sample, and this relative abundance of children at Cova Negra is similar that in to other Neandertal sites in Europe and southwest Asia. The recognition of diagnostic Neandertal features in several of the specimens, as well as their western European context and late Pleistocene age, suggests that all the human remains from Cova Negra represent Neandertals. The archaeological evidence from Cova Negra indicates sporadic, short-term occupations of the site, suggesting a high degree of mobility among Neandertals.

Adolescent↗

C957T DRD2 polymorphism is associated with schizophrenia in Spanish patients.

OBJECTIVE: The objective was to confirm whether a homozygous genotype for the C957 allele of the C957T DRD2 gene single nucleotide polymorphism (SNP) is associated with schizophrenia in an independent study population. METHOD: We examined the genotypic distribution of this SNP in a set of clinically ascertained schizophrenic patients (n = 131) and age-matched control subjects (n = 364). Individuals were genotyped using automated analysis of fluorescently labeled PCR products. RESULTS: The distribution of grouped genotypes for the C957T DRD2 SNP (CC vs. CT, TT) showed that C homozygote genotype was over-represented in our patient sample when compared with control subjects. This difference reaches the statistical significance (chi(2) = 7.0; df = 1; P = 0.008; OR = 2.05; % CI 1.2-3.4). CONCLUSION: The findings of this study provide additional evidence that genetic variation at the DRD2 gene plays an important role in the vulnerability to schizophrenia.

Adult↗

Effects of Hypericum perforatum on ivabradine pharmacokinetics in healthy volunteers: an open-label, pharmacokinetic interaction clinical trial.

The effects of the CYP3A4 inducer, Hypericum perforatum, on the pharmacokinetics of a single oral dose of ivabradine were assessed. An open-label, 2-period, nonrandomized, phase-I, pharmacokinetic interaction design was used. Twelve healthy volunteers received a single oral dose of ivabradine (10 mg) followed by H perforatum (300 mg orally, 3 times a day) for 14 days, combining the last dose with another single dose of ivabradine. Pharmacokinetic data for ivabradine (S16257) and its main active metabolite (S18982) prior to and after the administration of H perforatum were analyzed. After repeated administration of H perforatum, highest observed concentration in plasma (C(max)) and area under the concentration-time curve (AUC) were significantly decreased for ivabradine (32.7 +/- 16.6 vs 15.4 +/- 7.0 ng/mL, P < .01; 114 +/- 39.1 vs 43.7 +/- 12.0 ng x h/mL, P < .01, respectively), and for S18982 (C(max), 6.8 +/- 3.7 vs 5.1 +/- 2.0 ng/mL, P < .05; AUC, 56.2 +/- 23.4 vs 38.3 +/- 25.1 ng x h/mL, P < .01). Tendencies toward shorter time to C(max) and lower apparent terminal half-life values were found. Pharmacokinetic results are consistent with an induction of ivabradine metabolism by H perforatum.

Administration, Oral↗

Orogenital transmission of Neisseria meningitidis serogroup C confirmed by genotyping techniques.

Urethritis caused by Neisseria meningitidis in heterosexual patients is presumed to occur via orogenital contact, but confirmation has not been possible in most cases. Presented here is a case of urethritis caused by N. meningitidis, serogroup C, and the isolation of the same microorganism from the nasopharynx and endocervix of the patient's sexual partner. The similarity of the urethral and nasopharyngeal isolates' electrophoretic patterns, obtained using pulsed-field gel electrophoresis, proves the infection was transmitted via orogenital contact.

Adult↗

Auditory capacities in Middle Pleistocene humans from the Sierra de Atapuerca in Spain.

Human hearing differs from that of chimpanzees and most other anthropoids in maintaining a relatively high sensitivity from 2 kHz up to 4 kHz, a region that contains relevant acoustic information in spoken language. Knowledge of the auditory capacities in human fossil ancestors could greatly enhance the understanding of when this human pattern emerged during the course of our evolutionary history. Here we use a comprehensive physical model to analyze the influence of skeletal structures on the acoustic filtering of the outer and middle ears in five fossil human specimens from the Middle Pleistocene site of the Sima de los Huesos in the Sierra de Atapuerca of Spain. Our results show that the skeletal anatomy in these hominids is compatible with a human-like pattern of sound power transmission through the outer and middle ear at frequencies up to 5 kHz, suggesting that they already had auditory capacities similar to those of living humans in this frequency range.

Animals↗

[Effects of sevoflurane on mid-latency auditory evoked potentials and the 95% spectral frequency limit].

OBJECTIVES: To investigate the effects of sevoflurane on mid-latency auditory evoked potentials (MLAEP) and compare them to changes in the encephalographic 95% spectral edge frequency (SEF95). PATIENTS AND METHODS: The effect of sevoflurane on MLAEP and SEF95 was studied in 15 patients. Anesthetic induction was carried out with propofol, remifentanil, and cisatracurium. After anesthetic induction, the patients were ventilated to achieve different expired concentrations of sevoflurane (1%, 1.5%, and 2%) during 3 consecutive 10-minute periods before the start of surgery. SEF95 and the amplitude and latency of the Na, Pa and Nb MLAEP waves were recorded. All the parameters were measured at baseline and during the different expired fractions of sevoflurane. RESULTS: The increase in sevoflurane concentration was accompanied by a significant decrease in amplitude and a statistically significant increase in latency of the Na, Pa and Nb waves. Likewise, SEF95 decreased significantly. A linear relation was demonstrated between sevoflurane concentration and the variables Na, Pa, Nb and SEF95. CONCLUSIONS: Our results indicate that the effect of sevoflurane on the MLEAP of Na, Pa and Nb is similar to that of other anesthetic gases. Even though the amplitude of the Na, Pa and Nb waves decreased in a dose-dependent way, SEF95 correlated more strongly with sevoflurane concentration.

Adult↗

Epidemiological factors on hymenoptera venom allergy in a Spanish adult population.

BACKGROUND: The prevalence and risk factors of hymenoptera venom allergy (HVA) have been studied in several countries. However, there are few studies on the general population and these have very variable results. METHODS: An observational, prospective and cross-sectional study was carried out on a sample of 1064 subjects in a total working population of 7887 subjects (Ford factory, Spain) in order to know the prevalence of HVA in this population and the influence of several risk factors in its development. RESULTS: The rate of exposure to stings was 84.1% (ci 95%: 81.8-86.3%). The prevalence of HVA was 7.6% (ci 95%: 6.1-9.4%), with local severe reactions (LSR) in 5.3% (ci 95%: 4-6.8%) and systemic reactions (SR) in 2.3% (ci 95%: 1.5-3.4%). More than 82% of individuals over 20 years had already had some exposure, a figure that did not change in the age groups of older decades. In our study, the prevalence of HVA was not dependent on either age (similar age in all groups), sex: for LSR OR 2.75 (ci 95%: 0.37-20.30), for SR OR 0.54 (ci 95%: 0.12-2.38), or atopy OR 0.96 (ci 95%: 0.50-1.83); SR being more frequent among the residents of rural habitats, with ranges approaching statistically significant levels OR 2.15 (ci 95%: 0.95-4.81). The number of stings was larger in HVA group with respect a control group. The degree of venom sensitization measure by skin test and CAP-RAST was more intensive in SR group versus LSR group. Among vespids, sensitization to Polistes was more frequent than Vespula. CONCLUSIONS: HVA in our sample has a similar prevalence to other countries located in similar geo-climatic environments. Rural habitat and the number of stings suffered along life are risk factors of HVA development.

Adult↗

The adrenal cortex in experimental congenital diaphragmatic hernia.

BACKGROUND/PURPOSE: Adrenal cortical malfunction was found recently in patients with severe congenital diaphragmatic hernia (CDH). The current study tests the hypothesis that the development and function of the adrenal cortex could be abnormal in an experimental model of CDH. METHODS: Pregnant rats were exposed on day 9.5 of gestation to 100 mg of 2-4-dichlorophenyl-p-nitrophenyl ether (nitrofen) diluted in olive oil. The sham group was treated only with oil. Fetuses were recovered on the 21st day, bled, and examined for the presence or absence of CDH. Adrenal glands from sham and CDH animals were dissected, weighed, and prepared for histologic, biochemical, and immunohistochemical studies (ki-67) aimed at measuring total DNA, total protein, and the proportion of proliferating cells. Serum corticosterone levels were assayed. The results in both groups were compared with parametric tests with a significance level of P <.05. RESULTS: The adrenal weight was not different in CDH animals versus controls (0.049 +/- 0.014 v 0.052 +/- 0.012% of body weight; not significant). Total DNA was reduced significantly (1.180 +/- 0.481 v 1.909 +/- 0.893 microgram P <.05) with unchanged DNA to protein ratio. Proliferation index in both groups was 20.1 +/- 3.1% and 26.5 +/- 7.5%, respectively (not significant), and the proliferating cells were mainly located in the glomerular areas of the glands. Corticosterone levels were similar in both groups. CONCLUSIONS: Nitrofen induces very slight changes in the development of adrenal glands of fetal rats, expressed by reduced cell proliferation especially in glomerular areas, reduced total DNA with preservation of cell sizes (constant DNA to protein ratio), with no change in function because corticosterone levels remained unchanged. It is doubtful that primary adrenal malformation/malfunction contributes to the severity of CDH in this model.

Adrenal Cortex↗

[Impact of the protocol of ABO group and irregular antibodies on the transfusional index].

OBJECTIVES: The ABO group/irregular red cell antibodies (G/A) protocol is a scheme for reducing the number of unnecessary crossmatch tests in selected patients scheduled for surgery. Reduction would lower expenses and risks related to the overuse of such tests. Studying transfusion rates allows us to predict which patients are candidates for application of the protocol. The present study evaluated the impact of the G/A protocol on transfusion rate. PATIENTS AND METHODS: A retrospective analysis of pre-transfusion testing of patients in our hospital in 1996, before application of the G/A protocol, and in 2001, after four years of experience with the scheme. RESULTS: The G/A protocol was followed with 194 patients in 2001. The surgical transfusion rate decreased by 27.8% over the rate for 1996 (1.84 vs. 2.55). The outdating of blood units in 2001 decreased by 42.4% (65 units outdated vs. 113). Only one patient subject to the protocol had to be transfused. CONCLUSION: The transfusion rate can be significantly reduced by applying the G/A protocol with selected patients, with no loss of transfusion safety.

ABO Blood-Group System↗

[Role of diet in the management of osteodystrophy during progressive renal insufficiency].

Secondary hyperparathyrodism (SH) is an early manifestation of chronic renal failure (CRF), which has serious complications. Moreover, treating SH is not a risk-free process. Once in its advanced state, it is extremely difficult to reverse and therefore it is critical an early intervention and prevention. An excess of phosphorus and a deficit of calcium and calcitriol are key factors in the evolution of SH. Despite the fact that plasma phosphorus levels remain normal until an extremely advanced stage of CRF, and even apparent hyperphosphatemia in mild CRF, it has been shown that restricting dietary levels of protein and phosphorus impedes the progression of SH. A decrease of protein in the diet also decreases the amount of calcium, thus the calcium levels must be supplemented in order to prevent their deficit. In addition to that slightly diminished levels of calcitriol can be observed in the early stages of CRF, thus it is logical to provide this hormone. However, administering calcitriol may induce hypercalcemia and hyperphosphatemia, which in turn risks the onset of cardiovascular calcifications and complications. Therefore, the calcitriol dosage should be small and then adjusted according to the degree of SH. Neither the PTH levels nor alterations in the phospho-calcium metabolism follow a linear increase appropriate to the decrease in renal function, therefore we propose a treatment strategy which adapts to the different degrees of renal failure.

Calcinosis↗

Clone B7 cells have a single copy of SIVsmB7 integrated in chromosome 20.

B7 is the designation of a cell clone derived from the human cell line CEMx174, which was infected with SIVsmH3 clone. B7 cells chronically produce high quantities of non-infectious virus-like particles (VLP) denominated SIVsmB7. Here we report the molecular characterization of the B7 cell line. We found that B7 cells have a single copy of the SIVsmB7 provirus integrated in a noncoding region of chromosome 20 (nt 24,957 of clone RP5-963K23 on human chromosome 20q 13.11-13.2). Similarly to HIV and SIVmac, we show that integration of SIVsm results in a characteristic five base pair sequence repeat of host DNA that flanks the proviral DNA genome. Since the SIVsmB7 genome has a deletion in the IN coding sequence, the generation of this defective proviral genome most likely occurred during a faulty process of reverse transcription. Thus, these studies reveal the molecular clonality of the SIVsmB7 VLP produced by B7 cells. These genetically homogeneous VLP are useful reagents for vaccine development. In addition, these particles have been used by others (Montelaro et al.) to study the maturation of immune system responses to SIV infection.

Animals↗

Comparison of adsorption equilibrium and kinetics of four chlorinated organics from water onto GAC.

This study deals with the adsorption of four chlorinated pollutants onto GAC (F-400); two pesticides (lindane and alachlor) and two PCB congeners: 2-PCB (MPCB) and 2,2',5,5'-PCB (TPCB). Equilibrium and kinetic parameters have been obtained for the adsorption of alachlor and each PCB. whereas the kinetic results for lindane presented elsewhere (Proc. First World Water Congr. Int. Water Assoc., Texts of Posters, CD-ROM, AGHTM, Paris, 2000) are reanalyzed in this work. A model assuming a bidisperse structure (macro- and micropores). each region having a different adsorption isotherm, is used to study the adsorption kinetics in a batch system in the period dominated by macropore diffusion. Both the saturation capacity and the rate of internal transport of TPCB are much lower than those of the other solutes. This difference is attributed to a chemisorption mechanism for this compound, which is favored by its very low solubility.

Acetamides↗

Monteggia fractures in adults. Review of 54 cases.

INTRODUCTION: We present a review of Monteggia fractures treated in our hospital between 1992 and 1998. PATIENTS AND METHODS: Fifty four patients with a Monteggia fracture were treated in our hospital with an average follow-up of 24 months (12-48 months). The average age was 41 years (18-81 years). According to the classification of Bado, there were 24 type I, 20 type II, 6 type III and 4 type IV. The etiology was in 27 cases a motor-vehicle and motorcycle accident, five a pedestrian struck by a car, 21 by a causal fall and only one by a direct hit by an iron bar in an assault. In 56% of the patients, the lesions were associated with polytrauma. In all the cases, treatment consisted of open reduction and internal fixation of the ulnar fracture using different methods of osteosynthesis (3.5 mm DCP, 3.5 mm reconstruction plates, 6.5 mm cancellous screw, tension band technique with Kirschner wires, and one-third tubular plates). Initial treatment of the radial head dislocation was attempted by closed reduction and verification under fluoroscopy. Subsequent open reduction and osteosynthesis were performed in 10 cases, and resection of radial head was necessary in three cases as the initial treatment. There were six open fractures with one case developing chronic infection. RESULTS: Results were evaluated according to the criteria of Anderson (union fracture, elbow and wrist flexion/extension). The results were excellent in nine patients (17%), satisfactory in 33 (61%), unsatisfactory in nine (17%) and failure in three (5%). Complications could be attributed to the severity of injury, type of fixation and errors in technique (four non-union, three failure of one-third tubular plates, one distal radioulnar instability) and to some features peculiar to this lesion (five nerve injuries, three redislocations of the radial head and four radioulnar synostosis). We needed to perform 14 reoperations to resolve some of the above mentioned complications.

Adolescent↗

[Doxazosin, of modified liberation, in hemodialyzed patients].

INTRODUCTION: Valuation of doxazosin, system formulation modified, in the hypertension in the hemodialysis population. METHOD: Arterial Hypertension (AHT) has been studied in 77 patients (p) subjected to hemodialysis (HD). Mean age (mag) was 61 years (y), range 84y-25y; 66% were males. The underlying etiology was glomerular in 19%, tubulo-interstitial in 18%, congenital in 18%, vascular in 19% and diabetic in 26%. RESULTS: Doxazosin (system formulation modified, single daily dose (4 mg), treatment follow-up was completed in 16 patients subjected to HD for 24 weeks (wk). CONCLUSION: It is concluded that AHT is of great importance in HD, and can be adequately controlled with the new antihypertensive drugs. In this context, doxazosin affords excellent therapeutic control, efficiency and good pharmacological tolerance.

Adult↗

Only self-paced mating is rewarding in rats of both sexes.

When rats are mated in a traditional mating chamber (with one male and one female) in which the male dictates the pace of the copulatory sequence, males develop a reward state as evaluated by conditioned place preference (CPP). In this mating situation no reward state is induced in females. However, when female rats are able to control (pace) the rate of sexual stimulation, thereby reducing the aversive consequences associated with mating, a clear CPP is observed. In the present study the CPP paradigm was used to determine whether if the reinforced state induced by coital interactions in male rats can be maintained when females pace the sexual interaction. Adult male and female rats were mated in one of two different conditions: (1) where subjects were able to pace their coital interactions or (2) where subjects were not able to pace their sexual contacts. The results showed that when males had control over the sexual interaction they developed a clear place preference while males that mated with females that paced their coital contacts did not develop CPP. Similarly, only females that were able to pace their sexual contacts developed place preference. These results suggest that coital interactions in males, as well as in females, can induce a reward state only when they are able to control the sexual interaction. Under seminatural conditions sexual behavior in rats is highly promiscuous, they mate in groups and repeatedly change partners in the middle of copulation. This behavioral sequence allows both, male and female to control the rate of sexual interaction, assuring the induction of a reward state outlasting the actual performance of coital responses.

Animals↗