689 research outputs found
Análisis comparativo entre un tutor circular y uno monolateral en elongaciones óseas
El presente trabajo compara la funcionalidad de dos tutores externos utilizados
para elongación: el del Dr. Ilizarov y el tutor HG, desarrollado en nuestra institución. De 131
pacientes tratados con elongación ósea en 147 huesos largos se seleccionaron al azar 25 huesos
por cada aparato anteriormente mencionado. Para objetivar los resultados se registraron
estadísticamente variables independientes y dependientes en sus características subjetivas y objetivas,
tales como: edad, sexo, tipo de hueso elongado, tolerancia psíquica, sensación de confort,
facilidad de higiene y control, las infecciones, las rigideces articulares por retracción
músculo tendinosa, y la deformación ósea residual. El objetivo fue comparar y establecer si el
cambio en la elección del sistema fue ventajoso para nuestros pacientes. En el intento comparativo
se enfrentaron dos variables, que a nuestro criterio eran las más importantes para establecer
diferencias: la calidad del callo del hueso sometido a elongación y la presencia de
complicaciones tanto transitorias como definitivas.In this work we compare the results obtained with two different external fixation
devices in patients undergoing bone lengthening. The devices studied were the Ilizarov type
and the HG, an apparatons developed in our institution. Out of 131 patientes treated by
bone lengthening in 147 long bones, 25 bones lengthened with each device were selected at
random. Different subjective and objective variables were assessed: age, sex, type of bone, psichological
tolerance, patients, confort, nursing, infections, joint stiffness due to musculotendinous
retractions, and residual bone deformity. The aim of the study was to analyze if the
monolateral frame entailed advantages for our patients. Two main factors were more deeply
analysed, namely the quality of the bone callus subjected to lengthening and the presence of
both transitory and definitive complications
Volatile Composition and Outgassing in C/2018 Y1 (IWAMOTO): Extending Detection Limits for High-Resolution IR Cometary Spectroscopy at the NASA-IRTF
We used iSHELL, the powerful high-resolution ( /~ 40,000) cross-dispersed IR spectrograph at the NASA-IRTF to measure the native ice composition and outgassing of moderately bright, long-period comet C/2018 Y1 (Iwamoto) (hereafter Y1) within weeks of its discovery. We measured production rates for H2O, and production rates and abundance ratios relative to H2O for eight trace molecules, including the most complete measure of cometary CH4 achieved to date. Compared with mean abundances measured among comets, our study revealed enriched CH3OH and C2H6 yet depleted CO and C2H2, perhaps indicating highly efficient H- atom addition on interstellar grains prior to their incorporation into the nucleus. The combined high spectral resolving power and broad spectral coverage of iSHELL allowed characterizing cometary composition using only three instrument settings, and its long-slit coverage allowed comparing the spatial distributions of molecular emissions and dust continuum
Acute outcome after a single cryoballoon ablation: Comparison between Arctic Front Advance and Arctic Front Advance PRO
BACKGROUND:
The novel fourth-generation cryoballoon (CB4) potentially allows for enhanced catheter maneuverability and more frequent capture of pulmonary vein (PV) potentials which can be used to monitor real-time PV isolation (PVI). The aim of our study is to compare the acute procedural endpoints between the CB4 and second-generation cryoballoon (CB2).
METHODS:
A single-center retrospective chart review was used to examine 50 consecutive patients with drug-refractory atrial fibrillation undergoing CB4-based PVI. Procedural data and acute success of these patients were compared to 50 propensity-matched controls who underwent cryoballoon ablation procedure using CB2.
RESULTS:
Procedures performed with the CB4 showed significant shorter fluoroscopy time (14.8 \ub1 5.5 vs 18.0 \ub1 6.5 minutes, P = .04), shorter procedure time (58.3 \ub1 15.7 vs 65.3 \ub1 21 minutes, P = .13), and shorter total ablation time (10.8 \ub1 1.5 vs 13.8 \ub1 1.9 minutes, P = .42). The real-time PVI visualization rate was 33.3% in the CB2 group and 74.7% in the CB4 group (P < .001). CB4 was correlated to significant increase of acute real-time recordings with regard to all the single PV (left superior PV: 58% vs 84%, P = .02; left inferior PV: 26% vs 71%, P = .001; right superior PV 29% vs 61%, P = .01; and right inferior PV 19% vs 58%, P = .002).
CONCLUSION:
The CB4 was more often able to capture real-time recordings of PV potentials and the subsequent acute PV isolation
The composition of the protosolar disk and the formation conditions for comets
Conditions in the protosolar nebula have left their mark in the composition
of cometary volatiles, thought to be some of the most pristine material in the
solar system. Cometary compositions represent the end point of processing that
began in the parent molecular cloud core and continued through the collapse of
that core to form the protosun and the solar nebula, and finally during the
evolution of the solar nebula itself as the cometary bodies were accreting.
Disentangling the effects of the various epochs on the final composition of a
comet is complicated. But comets are not the only source of information about
the solar nebula. Protostellar disks around young stars similar to the protosun
provide a way of investigating the evolution of disks similar to the solar
nebula while they are in the process of evolving to form their own solar
systems. In this way we can learn about the physical and chemical conditions
under which comets formed, and about the types of dynamical processing that
shaped the solar system we see today.
This paper summarizes some recent contributions to our understanding of both
cometary volatiles and the composition, structure and evolution of protostellar
disks.Comment: To appear in Space Science Reviews. The final publication is
available at Springer via http://dx.doi.org/10.1007/s11214-015-0167-
The Future of Personalized Medicine in Space: From Observations to Countermeasures
The aim of personalized medicine is to detach from a “one-size fits all approach” and improve patient health by individualization to achieve the best outcomes in disease prevention, diagnosis and treatment. Technological advances in sequencing, improved knowledge of omics, integration with bioinformatics and new in vitro testing formats, have enabled personalized medicine to become a reality. Individual variation in response to environmental factors can affect susceptibility to disease and response to treatments. Space travel exposes humans to environmental stressors that lead to physiological adaptations, from altered cell behavior to abnormal tissue responses, including immune system impairment. In the context of human space flight research, human health studies have shown a significant inter-individual variability in response to space analogue conditions. A substantial degree of variability has been noticed in response to medications (from both an efficacy and toxicity perspective) as well as in susceptibility to damage from radiation exposure and in physiological changes such as loss of bone mineral density and muscle mass in response to deconditioning. At present, personalized medicine for astronauts is limited. With the advent of longer duration missions beyond low Earth orbit, it is imperative that space agencies adopt a personalized strategy for each astronaut, starting from pre-emptive personalized pre-clinical approaches through to individualized countermeasures to minimize harmful physiological changes and find targeted treatment for disease. Advances in space medicine can also be translated to terrestrial applications, and vice versa. This review places the astronaut at the center of personalized medicine, will appraise existing evidence and future preclinical tools as well as clinical, ethical and legal considerations for future space travel
The Growing Culture Of A Minimally Fluoroscopic Approach In Electrophysiology Lab
Most of interventional procedures in cardiology are carried out under fluoroscopic imaging guidance. Besides other peri-interventional risks, radiation exposure should be considered for its stochastic (inducing malignancy) and deterministic effects on health (tissue reactions like erythema, hair loss and cataracts). In this article we analized the radiation risk from cardiovascular imaging to both patients and medical staff and discusses how customize the X-ray system and how to implement shielding measures in the cath lab. Finally, we reviewed the most recent developments and the latest findings in catheter navigation and 3D electronatomical mapping systems that may help to reduce patient and operator exposure
Prevalence and clinical significance of collateral findings detected by chest computed tomography in patients undergoing atrial fibrillation ablation
Aims Chest computed tomography (CT) scanning is increasingly used as an imaging technique in patients undergoing atrial fibrillation (AF) catheter ablation. Chest CT scans visualize organs other than the heart and collateral findings may be identified incidentally. Our study aims to assess the prevalence and clinical relevance of such collateral findings in patients undergoing AF ablation.
Methods and results One hundred and seventy-three patients (127 males, age 59 +/- 10 years) underwent chest CT scan for image integration in AF ablation. Collateral findings from visualized thoracic and upper abdominal organs were collected. Findings that required further investigations or treatment according to current guidelines were considered as clinically significant. A total of 164 collateral findings were identified in 97 (56%) patients, and most patients showed abnormalities of the lungs (67 patients, 39%). Forty-nine (28%) patients had clinically significant findings needing further investigation and 17 (10%) of them required specific treatments, including three cases (1.7%) of lung malignancy.
Conclusions Chest CT images acquired for integration in AF ablation should be read thoroughly as they may serve as a screening tool for otherwise unrecognized clinically significant conditions of the heart, lungs, or other visualized organs
Genome-wide analyses of platinum-induced ototoxicity in childhood cancer patients: Results of GO-CAT and United Kingdom MAGIC consortia
: Hearing loss (ototoxicity) is a major adverse effect of cisplatin and carboplatin chemotherapy. The aim of this study is to identify novel genetic variants that play a role in platinum-induced ototoxicity. Therefore, a genome-wide association study was performed in the Genetics of Childhood Cancer Treatment (GO-CAT) cohort (n = 261) and the United Kingdom Molecular Genetics of Adverse Drug Reactions in Children Study (United Kingdom MAGIC) cohort (n = 248). Results of both cohorts were combined in a meta-analysis. In primary analysis, patients with SIOP Boston Ototoxicity Scale grade ≥1 were considered cases, and patients with grade 0 were controls. Variants with a p-value <10-5 were replicated in previously published data by the PanCareLIFE cohort (n = 390). No genome-wide significant associations were found, but variants in TSPAN5, RBBP4P5, AC010090.1 and RNU6-38P were suggestively associated with platinum-induced ototoxicity. The lowest p-value was found for rs7671702 in TSPAN5 (odds ratio 2.0 (95% confidence interval 1.5-2.7), p-value 5.0 × 10-7). None of the associations were significant in the replication cohort, although the effect directions were consistent among all cohorts. Validation and functional understanding of these genetic variants could lead to more insights in the development of platinum-induced ototoxicity
Pharmacological inhibition of Akt and downstream pathways modulates the expression of COX-2 and mPGES-1 in activated microglia
<p>Abstract</p> <p>Background</p> <p>Microglia are considered a major target for modulating neuroinflammatory and neurodegenerative disease processes. Upon activation, microglia secrete inflammatory mediators that contribute to the resolution or to further enhancement of damage in the central nervous system (CNS). Therefore, it is important to study the intracellular pathways that are involved in the expression of the inflammatory mediators. Particularly, the role of the phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) and glycogen synthase kinase-3 (GSK-3) pathways in activated microglia is unclear. Thus, in the present study we investigated the role of Akt and its downstream pathways, GSK-3 and mTOR, in lipopolysaccharide (LPS)-activated primary rat microglia by pharmacological inhibition of these pathways in regard to the expression of cyclooxygenase (COX)-2 and microsomal prostaglandin E synthase-1 (mPGES-1) and to the production of prostaglandin (PG) E<sub>2 </sub>and PGD<sub>2</sub>.</p> <p>Findings</p> <p>We show that inhibition of Akt by the Akt inhibitor X enhanced the production of PGE<sub>2 </sub>and PGD<sub>2 </sub>without affecting the expression of COX-2, mPGES-1, mPGES-2 and cytosolic prostaglandin E synthase (cPGES). Moreover, inhibition of GSK-3 reduced the expression of both COX-2 and mPGES-1. In contrast, the mTOR inhibitor rapamycin enhanced both COX-2 and mPGES-1 immunoreactivity and the release of PGE<sub>2 </sub>and PGD<sub>2</sub>. Interestingly, NVP-BEZ235, a dual PI3K/mTOR inhibitor, enhanced COX-2 and reduced mPGES-1 immunoreactivity, albeit PGE<sub>2 </sub>and PGD<sub>2 </sub>levels were enhanced in LPS-stimulated microglia. However, this compound also increased PGE<sub>2 </sub>in non-stimulated microglia.</p> <p>Conclusion</p> <p>Taken together, we demonstrate that blockade of mTOR and/or PI3K/Akt enhances prostanoid production and that PI3K/Akt, GSK-3 and mTOR differently regulate the expression of mPGES-1 and COX-2 in activated primary microglia. Therefore, these pathways are potential targets for the development of novel strategies to modulate neuroinflammation.</p
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