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31.
Macías Batista A Martínez Martín FJ de Pablos Velasco PL 《Anales de medicina interna (Madrid, Spain : 1984)》1999,16(2):87-88
A fourteen-year male patient presented a retrochiasmatic craniopharyngioma. Aer transcranial surgical resection, the patient had diabetes insipidus, which presented an interphase with manifestations of inadequate secretion of ADH. The patient was adequately treated with intranasal desmopresin, but aer i.v. fluid replacement was withdrawn, severe dehydration occurred. This was attributed to loss of the thirst reflex, due to surgical lesion of the lamina terminalis, where the osmoreceptor neurons are located. This case underscores the complications with body fluids and osmolality which may occur after surgery of hypothalamic lesions; i.e. diabetes insipidus (which may have a triphasic course), and adipsia, an infrequent complication due to absence of thirst. 相似文献
32.
Cerveró C Escribano L San Miguel JF Díaz-Agustín B Bravo P Villarrubia J García-Sanz R Velasco JL Herrera P Vargas M González M Navarro JL Orfao A 《American journal of hematology》1999,60(3):191-195
Bcl-2 protein plays a major role in the prevention of programmed cell death of differentiating cells. In the present study, the expression of cytoplasmic bcl-2 by human Bone Marrow Mast Cells (BMMC) from both normal and pathological bone marrow samples was examined. A total of 35 subjects corresponding to 9 healthy volunteers, 8 cases of adult indolent systemic mast cell disease (SMCD), 4 cases of pediatric mastocytosis (PM), 11 cases of hematological malignancies (HM), 2 cases of reactive bone marrow, and 1 case of mast cell leukemia (MCL) were analyzed. The expression of bcl-2 was studied using quantitative three-color flow cytometry. We also studied the molecular configuration of the bcl-2 gene and other relatives by Southern blot and polymerase chain reaction (PCR) in the MCL case. Bcl-2 expression was detected in BMMC from all samples analyzed. No significant differences on the expression of bcl-2 were detected between BMMC from healthy subjects and patients with SMCD, PM, HM, and reactive bone marrow. By contrast, bcl-2 protein was overexpressed in BMMC from MCL patient without gene rearrangement. Our results show that bcl-2 protein was constitutively expressed by BMMC. BMMC from MCL display overexpression of bcl-2, which could not be related to molecular rearrangements involving the bcl-2 gene. The expression of this protein by mature MC may play a role in the prevention of MC apoptosis and thus help to explain the long survival of these cells. The overexpression of bcl-2 by BMMC in MCL may help to explain their resistance to chemotherapy-induced apoptosis. 相似文献
33.
Amy K. Feehan Daniel Fort Cruz Velasco Jeffrey H. Burton Julia Garcia-Diaz Eboni G. Price-Haywood Eric Sapp Dawn Pevey Leonardo Seoane 《Clinical microbiology and infection》2021,27(4):633.e9-633.e16
ObjectiveWhile many seroprevalence studies of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been performed, few are demographically representative. This investigation focused on defining the nature and frequency of symptomatic and asymptomatic SARS-CoV-2 infection in a representative, cross-sectional sample of communities in Louisiana, USA.MethodsA sample of 4778 adults from New Orleans and Baton Rouge, Louisiana were given a survey of symptoms and co-morbidities, nasopharyngeal swab to test for active infection (PCR), and blood draw to test for past infection (IgG). Odds ratios, cluster analysis, quantification of virus and antibody, and linear modelling were used to understand whether certain symptoms were associated with a positive test, how symptoms grouped together, whether virus or antibody varied by symptom status, and whether being symptomatic was different across the age span.ResultsReported anosmia/ageusia was strongly associated with a positive test; 40.6% (93/229) tested positive versus 4.8% (218/4549) positivity in those who did not report anosmia/ageusia (OR 13.6, 95% CI 10.1–18.3). Of the people who tested positive, 47.3% (147/311) were completely asymptomatic. Symptom presentation clustered into three groups; low/no symptoms (0.4 ± 0.9, mean ± SD), highly symptomatic (7.5 ± 1.9) or moderately symptomatic (4.0 ± 1.5). Quantity of virus was lower in the asymptomatic versus symptomatic group (cycle number 23.3 ± 8.3 versus 17.3 ± 9.0; p < 0.001). Modelling the probability of symptoms showed changes with age; the highest probability of reporting symptoms was 64.6% (95% CI 50.4–76.5) at age 29 years, which decreased to a probability of 49.3% (95% CI 36.6–62.0) at age 60 years and only 25.1% (95% CI 5.0–68.1) at age 80 years.ConclusionAnosmia/ageusia can be used to differentiate SARS-CoV-2 infection from other illnesses, and, given the high ratio of asymptomatic individuals, contact tracing should include those without symptoms. Regular testing in congregant settings of those over age 60 years may help mitigate asymptomatic spread. 相似文献
34.
35.
Maritza Del Carmen Quezada‐Conde Patricia de Lourdes Alvarez‐Velasco Edisson Fernando Lopez Marco Vinicio Medina Renata Pereira de Samuel Marques Marcia Turolla Wanderley E. Michel-Crosato Claudio Mendes Pannuti Antonio Carlos Frias Daniela Prcida Raggio Fausto Medeiros Mendes 《Dental traumatology》2020,36(5):510-517
36.
L. Pierot J. Moret F. Turjman D. Herbreteau H. Raoult X. Barreau S. Velasco H. Desal A.-C. Januel P. Courtheoux J.-Y. Gauvrit C. Cognard S. Soize A. Molyneux L. Spelle 《AJNR. American journal of neuroradiology》2015,36(5):922
BACKGROUND AND PURPOSE:Safety analyses in the French Observatory have shown that treatment of intracranial aneurysms by using flow disruption with the Woven EndoBridge Device (WEB) is safe, with low morbidity and no mortality. The objective of this study was to analyze treatment feasibility, complications, and safety results in patients treated with the Woven EndoBridge Device Dual-Layer (WEB DL) and Woven EndoBridge Device Single-Layer/Single-Layer Sphere (WEB SL/SLS) in the French Observatory.MATERIALS AND METHODS:Patients with bifurcation aneurysms were included in this prospective, multicenter good clinical practices study. A medical monitor independently analyzed procedural and clinical data. The study started with the WEB DL, and secondarily, the WEB SL/SLS was authorized in the study.RESULTS:Between November 2012 and January 2014, 10 French centers included 62 patients with 63 aneurysms. Thirty patients with 31 aneurysms were treated with the WEB DL, and 32 patients with 32 aneurysms, with the WEB SL/SLS. The percentage of anterior communicating artery aneurysms treated with WEB SL/SLS was significantly higher (37.5%) compared with WEB DL (12.9%) (P = .04). The WEB SL/SLS was more frequently used in aneurysms of <10 mm than the WEB DL (respectively, 96.9% and 67.7%; P = .002). Morbidity was similar in both groups (WEB DL, 3.3%; WEB SL/SLS, 3.1%), and mortality was 0.0% in both groups.CONCLUSIONS:This comparative study shows increased use of WEB treatment in ruptured, small, and anterior communicating artery aneurysms when using WEB SL/SLS. There was a trend toward fewer thromboembolic complications with the WEB SL/SLS. With both the WEB DL and WEB SL/SLS, the treatment was safe, with low morbidity and no mortality.Endovascular treatment is the preferred therapeutic option for ruptured aneurysms that are anatomically suitable for endovascular coil treatment, supported by randomized studies, especially in locations less suitable for surgery.1,2 It also has an important place in the management of unruptured aneurysms that are judged appropriate for treatment.3 Complex aneurysms (fusiform, wide-neck, large, or giant) are often untreatable or difficult to treat with standard coiling. For these complex cases, endovascular techniques such as balloon-assisted coiling, stent-assisted coiling, or flow diversion have been used with good results.4–9Flow disruption is a new endovascular approach, which involves placement of a Woven EndoBridge Device (WEB; Sequent Medical, Aliso Viejo, California), which modifies the blood flow at the level of the neck and induces intra-aneurysmal thrombosis. The WEB was designed initially to treat wide-neck and bifurcation aneurysms. The initial clinical results have shown that treatment is feasible with a low level of complications, low morbidity, and no mortality.10–14 The device has been progressively developed from a dual-layer version (WEB Dual-Layer [DL] aneurysm embolization system; Sequent Medical) to single-layer versions (WEB Single-Layer [SL] and WEB Single-Layer Sphere [SLS]).The French Observatory is a prospective, multicenter observational study of consecutive cases, with independent monitoring, across 10 French centers.It has 2 major objectives:
- To carefully evaluate the safety of this treatment with an independent assessment of all adverse events and morbidity/mortality.
- To evaluate the efficacy of this treatment at 12 and 24 months with independent core lab adjudication.
37.
38.
M Ledesma Velasco R Verdín Vázquez J L Acosta Valdez J Munayer Calderón J L Salgado Escobar L Arias Monroy J Flores Mendoza 《Archivos del Instituto de Cardiología de México》1989,59(1):69-71
We performed catheter balloon valvuloplasty (CBV) on 8 stenotic operatively-excised bioprosthetic valves (2 Hancock and 6 Ionescu Shiley). Pathology of valves before CBV included degenerative changes: commissural fusion by mounds of calcific deposits (2 valves), fibrotic and focally calcified leaflets (7 valves) and stiff and thick valves (1 valve). Inflation of the balloon resulted in commissural splitting (2 valves), leaflet cracks and fractures (3 valves). Removal of the deflated balloon catheter was associated with debris dislodgement (3 valves). In one case the valve was unable to close with potential for acute regurgitation. Thus, CBV of bioprosthetic valves can split fused commissures by similar mechanisms as in native valves. CBV may fracture calcific deposits causing acute emboli. It can also disrupt the leaflets causing acute insufficiency. The findings suggest a limited role of CBV in the treatment of stenotic bioprosthetic valves in mitral and aortic position. 相似文献
39.
Hernndez Mariana Dolores Alma Villaseor Olmos Sofia Pia Crisforo Mercado Mrquez Benjamín Velasco Bejarano María Eugenia Gonsebatt Bonaparte Raquel Lpez‐Arellano 《Drug testing and analysis》2019,11(8):1238-1247
Clenbuterol is known to improve competition resistance and muscular growth in athletes. Although it is an illegal drug, its use by farmers is widely spread to induce growth of their cattle. Thus, when clenbuterol is found in the urine of an athlete, there is doubt whether it was consumed with doping purposes or if it is due to the consumption of meat from a clenbuterol‐fed animal. Previous studies suggest that enantiomeric relationship of clenbuterol may be different according to the intake source. However, the enantiomeric relationship throughout a doping cycle or a continuous intake of contaminated meat has not yet been explored. In this first approximation, our aim was the development and validation of a sensitive and rapid method for the determination of S‐ (+) and R‐ (─) clenbuterol enantiomers to be used in a controlled study in rats fed for one week with contaminated meat or simulating a doping cycle. Enantiomers were measured using liquid chromatography coupled to mass spectrometry with a triple quadrupole analyzer (LC‐TQ‐MS) and were separated on an AGP Chiralpak column. The method was fully validated following the VICH (Veterinary International Conference on Harmonization guidelines) and was linear in the range of 12.5–800 pg/mL with a correlation coefficient of ≥0.98 for each enantiomer, and with a limit of quantitation and detection (LOQ and LOD) of 12.5 pg/mL and 6.5 pg/mL, respectively, for both enantiomers. The application of this method pointed out the shift of the enantiomeric relationship in urine from rats during the first five days of the doping cycle compared to those fed with contaminated meat. This finding can be of substantial importance in further doping studies. 相似文献
40.
Perez-Sanchez C Ruiz-Limon P Aguirre MA Bertolaccini ML Khamashta MA Rodriguez-Ariza A Segui P Collantes-Estevez E Barbarroja N Khraiwesh H Gonzalez-Reyes JA Villalba JM Velasco F Cuadrado MJ Lopez-Pedrera C 《Blood》2012,119(24):5859-5870
The exact mechanisms underlying the role of oxidative stress in the pathogenesis and the prothrombotic or proinflammatory status of antiphospholipid syndrome (APS) remain unknown. Here, we investigate the role of oxidative stress and mitochondrial dysfunction in the proatherothrombotic status of APS patients induced by IgG-antiphospholipid antibodies and the beneficial effects of supplementing cells with coenzyme Q(10) (CoQ(10)). A significant increase in relevant prothrombotic and inflammatory parameters in 43 APS patients was found compared with 38 healthy donors. Increased peroxide production, nuclear abundance of Nrf2, antioxidant enzymatic activity, decreased intracellular glutathione, and altered mitochondrial membrane potential were found in monocytes and neutrophils from APS patients. Accelerated atherosclerosis in APS patients was found associated with their inflammatory or oxidative status. CoQ(10) preincubation of healthy monocytes before IgG-antiphospholipid antibody treatment decreased oxidative stress, the percentage of cells with altered mitochondrial membrane potential, and the induced expression of tissue factor, VEGF, and Flt1. In addition, CoQ(10) significantly improved the ultrastructural preservation of mitochondria and prevented IgG-APS-induced fission mediated by Drp-1 and Fis-1 proteins. In conclusion, the oxidative perturbation in APS patient leukocytes, which is directly related to an inflammatory and pro-atherothrombotic status, relies on alterations in mitochondrial dynamics and metabolism that may be prevented, reverted, or both by treatment with CoQ(10). 相似文献