[Spontaneous idiopathic hemothorax in a healthy adolescent].
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Biomedical subjects
Publications and source records attributed to M Martínez.
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Since it has been proposed that oxygen radical inactivation of key enzymes plays a critical role in cell aging, we have investigated the effects of a thiolic free radical scavenger on the oxidative phosphorylation enzymes of liver mitochondria from female OF-1 mice. At 48 weeks of age a control group was fed standard food pellets and another group received pellets containing 0.3% (w/w) of N-acetylcysteine. A 24-week treatment resulted in a significant increase in the specific activities of complex I, IV and V in the hepatic mitochondria of the N-acetylcysteine-treated animals as compared to aged controls.
To investigate the possible existence of age-related changes in excitatory amino acid release in brain, and the influence of glucose deprivation on this process, we have determined the release of endogenous aspartate and glutamate from synaptosomes freshly isolated from the cerebrum of young (12 months old) and aged (24 months old) mice. We found that there are no age-related changes in the synaptosomal release of aspartic and glutamic acids. However, in the absence of glucose in the medium of incubation aspartate and glutamate release was higher in old than in young animals (P < 0.05, and P = 0.09 respectively). Our results suggest that the ability of cerebral synaptosomes to release glutamate and aspartate remains functionally intact in old cerebrum, but there is an age-dependent dysfunction in this process linked to energy metabolism disturbances.
The existence of leukemic-associated phenotypes has been suggested to be a valuable tool for the detection of minimal residual disease (MRD) in AML patients, as they would allow to distinguish leukemic blast cells from normal hematopoietic progenitors. The present study was designed to analyze in which proportion of AML patients the immunological detection of MRD is feasible, based on the presence of aberrant phenotypes that allow the distinction of leukemic from normal cells. For this purpose we have prospectively investigated the blast cells from 40 AML patients at diagnosis with a large panel of MoAb in double and triple staining combinations analyzed at flow cytometry, in order to detect aberrant phenotypes on blast cells (lineage infidelity, antigenic overexpression, and asynchronous antigenic expression, as well as aberrant light-scatter pattern). In the analysis of the 40 AML cases more than one blast cell subset, distinguished by its different antigenic expression, was detected in 85% of the patients: five different phenotypic blast cell subsets were observed in six cases, four in 13 patients, three subsets in three cases, and two in 12 patients; only six cases showed a homogeneous phenotypical blast cell population. Twenty-nine of the 40 AML cases analyzed (73%) showed the existence of at least one aberrant phenotype: in 15 cases the myeloid blast cells co-expressed lymphoid-associated antigens (CD2, CD5, CD7, and/or CD19)--lineage infidelity--; asynchronous antigen expression was detected in 25 patients (CD34+CD56+, CD34+CD11b+, CD34+CD14+, CD117+CD15+, CD33-CD13+, CD13-CD15+, HLADR + CD15 , HLADR-CD14+CD11b+ CD4+); seven cases displayed antigen overexpression (CD13, CD33, CD15, or CD14); and in 13 patients leukemic cells had an abnormal FSC/SSC distribution according to their phenotype. These results suggest that immunological methods for the detection of MRD based on the existence of aberrant phenotypes could be used in the majority of AML patients.
The aim of this work was to study the hypothesis that the release of vasoactive neuropeptides may be related to the hemodynamic changes and severity of disease in human sepsis and septic shock. Twenty-two patients diagnosed with sepsis and treated in medical wards with standard supportive therapy and twenty patients admitted to a medical intensive care unit because of septic shock were studied Twenty healthy volunteers in a similar age range were enrolled as control group. Blood samples were taken at onset and every 12 hours on the following day after hospital admission to measure plasma concentrations of calcitonin gene-related peptide (CGRP), neuropeptide Y (NPY) and substance P (SP). Clinical and biochemical variables were measured simultaneously. The Acute Physiology and Chronic Health Evaluation (APACHE) II score was calculated on admission. From the day of admission, septic shock patients had significantly higher plasma CGRP-like immunoreactivity levels than patients with sepsis, as well as both groups of patients compared to control subjects. Plasma NPY-like immunoreactivity levels in patients with either sepsis or septic shock was significantly increased, and plasma SP-like immunoreactivity levels significantly reduced compared to those in controls. Plasma CGRP levels at study entry correlated with the APACHE II score (r = 0.71, p < 0.01), as well as with the cardiac index (r = 0.61, p < 0.05) and systemic vascular resistance index (r = -0.62, p < 0.05). Our data suggest that both CGRP and NPY, but not SP, are increasedly released into the circulation during the development of human sepsis and septic shock. In patients with sepsis the vasoconstriction mediated by the release of NPY appears to counterbalance the vasodilatory effect of CGRP. In septic shock patients, however, the release of NPY might be inadequately low to overcome the widespread CGRP-induced vasodilation.
This study assessed the reinforcing properties of successful intermale agonistic encounters between OF1 male mice using the conditioned place preference paradigm. A three compartment apparatus was used and the procedure consisted of three phases: preconditioning (3 days), conditioning (8 days) and postconditioning (3 tests). Individually housed male mice were allocated to two groups. The aggression group confronted docile opponents in the preconditioning "less-preferred" compartment and were left alone in the "preferred" one. The control group was left alone in both compartments. Whereas no significant differences were found between both groups in the time spent in the less-preferred compartment, a separate analysis of animals in function of the color of the less-preferred compartment revealed a clear-cut difference. Mice developed a conditioned place preference for the aggression-paired compartment only if that experience took place in the black one. These findings suggest that the process of establishing a conditioned place preference with successful intermale aggression as reinforcer is extremely fragile and can be easily disrupted by changing the environmental cues involved.
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The structure of the polysaccharide from Cercidium praecox (R&P) Harms gum exudate has been studied by Smith degradation, by sugar and methylation analyses, and by 13C NMR spectroscopy. The results showed a (1-->4)-xylan core. Some xylose residues are substituted at O-2 by alpha-D-glucuronic acid and 4-O-methyl-alpha-D-glucuronic acid residues. beta-D-Glucuronic acid is present, probably as terminal residues. The arabinose is present as alpha-L-furanose and beta-L-pyranose.
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A multicenter, double-masked, parallel-group clinical trial was carried out in 151 patients with moderate to severe chronic conjunctivitis. The study compared the antiinflammatory efficacy and safety of pranoprofen 0.1%, a new cyclo-oxygenase inhibitor, with fluorometholone 0.1%, after topical doses four times a day for 15 days. The basal mean score for the signs and symptoms of inflammation, was significantly reduced (P < .001), with no significant difference between the two groups, at days 8 and 15. There was a statistically significant difference of approximately 1.0 mm Hg (P < .05) in the mean intraocular pressure between treatment, which was a decrease of 0.3 mm Hg with pranoprofen and an increase of 0.8 mm Hg with fluorometholone. One patient in the pranoprofen group had an adverse experience, compared to nine patients in the fluorometholone group (P < .03). Our data suggest that pranoprofen has efficacy equivalent to a moderate-potency corticosteroid with a better safety profile. It should be considered for the treatment of chronic conjunctivitis of presumed nonbacterial origin.
To elucidate the role of mitochondrial oxidative phosphorylation in neuronal aging, we have studied the activity of the respiratory complexes in the brain of young, adult and old mice. In synaptic mitochondria, we found a significant decrease in complexes IV (29%, P < 0.001) and V (21%, P < 0.01) in old as compared with adult mice. Nonsynaptic mitochondria also showed a senescent decrease in complexes I (15%, P < 0.01), II + III (34%, P < 0.01) and IV (17%, P < 0.01) activities. These findings suggest a dysfunction in mitochondrial oxidative phosphorylation in brain aging.
To elucidate the contribution of lipid peroxides and glutathione to brain aging, we have carried out a comparative study of their contents in synaptic mitochondria from young (10-week-old), adult (24-week-old), and senescent (72-week-old) mice. In synaptic mitochondria, there is a significant decline in lipid peroxide content (P < 0.01) and cytochrome c oxidase activity (P < 0.001) in senescent as compared to adult and young mice. By contrast, glutathione concentration showed an increase in senescent (P < 0.05) in comparison to the other age groups. Moreover, there was a significant inverse correlation between age and lipid peroxide content (r = -0.5, P < 0.001) or cytochrome c oxidase-specific activity (r = -0.58, P < 0.001). We suggest that this age-dependent decrease in lipid peroxide content in synaptic mitochondria may be the result of an age-related decline in the activity of the electron transport chain, with concomitant decrease in oxyradical production, in the senescent organelles.
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The effectiveness of surgery in patients with refractory complex partial seizures depends on accurate localisation of the epileptogenic zone. To assess the correlation between magnetic resonance imaging (MRI) hippocampal volume measurements. Tc 99m-hexamethyl-propyleneamineoxime inter- and postictal single photon emission computed tomography (SPECT) and clinico-electrophysiological (video/EEG) localisation of the epileptogenic zone we prospectively studied 16 consecutive patients with refractory complex partial seizures and no significant abnormality on standard MRI. Each test was interpreted blindly by independent observers. Eight patients (50%) had asymmetrical hippocampal volumes indicative of unilateral atrophy; correlation with the video/EEG and postical SPECT changes was very high (100% with definitive video/EEG localisation, 75% with interictal EEG and 83% with postictal SPECT). Moreover, the left/right hippocampal ratio was able to differentiate temporal from extratemporal video/EEG localisations. Postictal SPECT showed regional lateralised changes in 9 (64%) of 14 technically satisfactory studies. Disagreement between the video/EEG and postictal SPECT was seen with two extratemporal and one bitemporal foci.
An open prospective clinical trial designed to evaluate the efficacy and safety of the combined hormonal oral contraceptive (OC) containing 75 micrograms gestodene plus 30 micrograms ethinyl estradiol was undertaken in a Mexican population. Sixty-nine healthy women of reproductive age took part in the study for a total of 627 woman-months of observation. The combination of gestodene and ethinyl estradiol proved its effectiveness in preventing pregnancy during the study. Side-effects were minimal and regular endometrial bleeding patterns were observed during one year of continuous use of this OC preparation. The discontinuation rate for medical reasons was 11.6% at one year. Among a sample of 10 women, the gestodene/ethinyl estradiol combination did not induce significant changes in the serum concentration of total cholesterol and LDL cholesterol after 12 months of continuous administration. An increase in serum triglycerides and HDL cholesterol was observed; this effect could be attributed to a lack of androgenic and/or the intrinsic estrogenic behavior of gestodene. It can be concluded that this preparation is highly effective as a combined oral contraceptive; it is well tolerated and might offer some advantages with respect to other oral contraceptive combinations in its short- and medium-term impact on lipid metabolism.
A new demand feeder was designed for the automatic and accurate feeding of fish. The feeding device is microcomputer controlled and permits the continuous recording of feeding behaviour. The electromechanical feeder consists of a sliding door powered by a solenoid which provides only one weighed pellet when activated by the fish. Some preliminary results on feeding behaviour in sea bass are presented to test the efficiency of the feeder.
Eleven entire and twelve castrated male pigs were implanted with trenbolone acetate and the effects of the treatment on genital tract macro- and microscopical modifications were evaluated and compared to non-implanted animals. In entire male pigs a reduction of testicular weight and size was observed as a consequence of the treatment (< 0.001), but no important modifications were found in bulbourethral gland and seminal vesicles macroscopically. Castrated non-implanted males had bulbourethral gland atrophy (P < 0.01), while castrated implanted ones showed similar development to entire males. As for vesicular glands there were no significant differences among the four groups under study. Histological study of prostate has demonstrated structural modifications. As a consequence of the treatment glandular lumen was increased (P < 0.05), and most parenchyma was occupied by polymorphous cysts.