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In this review, the Hymenoptera Allergy Committee of the SEAIC analyzes the most recent scientific literature addressing problems related to the diagnosis of hymenoptera allergy and to management of venom immunotherapy. Molecular diagnosis and molecular risk profiles are the key areas addressed. The appearance of new species of hymenoptera that are potentially allergenic in Spain and the associated diagnostic and therapeutic problems are also described. Finally, we analyze the issue of mast cell activation syndrome closely related to hymenoptera allergy, which has become a new diagnostic challenge for allergists given its high prevalence in patients with venom anaphylaxis.
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Venenos de Artrópodos/inmunología , Himenópteros/inmunología , Hipersensibilidad/inmunología , Mordeduras y Picaduras de Insectos/inmunología , Animales , Venenos de Artrópodos/uso terapéutico , Hipersensibilidad/diagnóstico , Hipersensibilidad/epidemiología , Hipersensibilidad/terapia , Pruebas Inmunológicas , Inmunoterapia/métodos , Mordeduras y Picaduras de Insectos/diagnóstico , Mordeduras y Picaduras de Insectos/epidemiología , Mordeduras y Picaduras de Insectos/terapia , Valor Predictivo de las Pruebas , Factores de Riesgo , Índice de Severidad de la Enfermedad , España/epidemiología , Resultado del TratamientoRESUMEN
BACKGROUND: The latest recommendations from the American Heart Association and the European Resuscitation Council invite allowance for the presence of relatives (PR) during cardiopulmonary resuscitation (CPR) as an extra measure of family care. OBJECTIVE: To discover the opinion of health professionals on the PR during CPR. METHOD: Cross-sectional observational study through an online survey in Spain, based on a non-probability sample (n=315). RESULTS: 45% consider that the PR during CPR is not demanded by users. 64% value the implementation of this practice in a negative or a very negative way. 45% believe that the practice would avoid the feeling of abandonment that is instilled in the relatives, this being the most widely perceived potential benefit. 30% do not believe that it can help reduce the anxiety of relatives. The majority remarked that PR would cause situations of violence, psychological harm in witnesses, and more mistakes during care. 48% feel prepared to perform the role of companion. CONCLUSIONS: Most professionals perceive more risks than benefits, and are not in favour of allowing PR due to a paternalistic attitude, and fear of the reactions that could be presented to the team. Extra-hospital emergency personnel seems to be the group most open to allowing this practice. Most professionals do not feel fully prepared to perform the role of companion.
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Actitud del Personal de Salud , Reanimación Cardiopulmonar , Familia , Relaciones Profesional-Familia , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
We investigated the antibiotic and heavy-metal resistance mechanisms, virulence genes and clonal relationships of macrolide- and/or lincosamide-resistant (M+/-LR) Streptococcus agalactiae (group B Streptococcus, GBS) isolates from pregnant women in La Rioja in Northern Spain, a region with a significant immigrant population. In total 375 GBS isolates were recovered during 2011. About three-quarters of isolates were from European nationals and the remainder distributed among 23 other nationalities. Seventy-five (20%) were classified as M+/-LR strains and 28 (37%) of these were resistant to ⩾3 classes of antibiotics. Capsular serotypes III (29·3%), V (21·3%) and II (12%) were the most frequent. A wide variety of antibiotic resistance genes were detected in M+/-LR strains; notably, 5·3% harboured the lsa(C) gene associated with cross-resistance, and tet(W) was identified in a single strain. We report, for the first time, the detection of cadmium and copper resistance encoded by tcrB + cadA + cadC genes in 20 M+/-LR strains, which raises the possibility of co-selection of antibiotic and heavy-metal resistance disseminated through mobile genetic elements. The M+/-LR strains were highly diverse by DNA macrorestriction profiles (65 patterns) and 16 multilocus sequence types (STs) distributed among six clonal complexes; the most frequent were ST1, ST19, and ST12, and two strains were novel (ST586 and ST601). In conclusion, a wide diversity of genetic lineages of macrolide, lincosamide and heavy-metal- resistant GBS strains was observed in an ethnically diverse maternal population.
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Antibacterianos/farmacología , Farmacorresistencia Bacteriana/genética , Metales Pesados/toxicidad , Infecciones Estreptocócicas/epidemiología , Streptococcus agalactiae/efectos de los fármacos , Streptococcus agalactiae/genética , Virulencia/efectos de los fármacos , Adolescente , Adulto , Femenino , Humanos , Lincosamidas/farmacología , Macrólidos/farmacología , Persona de Mediana Edad , Embarazo , España/epidemiología , Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae/patogenicidad , Streptococcus agalactiae/fisiología , Virulencia/genética , Factores de Virulencia/genética , Adulto JovenAsunto(s)
Anafilaxia , Himenópteros , Hipersensibilidad , Mordeduras y Picaduras de Insectos , Animales , Humanos , Calidad de VidaRESUMEN
OBJECTIVE: To acknowledge the challenges and limitations of image-guided neurosurgery systems, we compared the application accuracy of two different image registration methods for one commercial system. (VectorVision, BrainLab, Germany). METHODS: We used an anthropomorphic head phantom for radiosurgery and a custom built add-on to simulate surgical targets inside the brain during an image-guided neurosurgery. We used two image registration methods, fiducial registration using attachable surface markers for computed tomography (CT) and surface registration using infrared laser face scanning. After simulation, we calculated the three-dimensional (3D) distance between the predicted position of a target, and its actual position using a registered pointer and an infrared camera. Deviations were measured for both superficial fiducial markers and internal surgical targets by five different users. RESULTS: Deviations from the location of fiducial markers after each registration method were 2.15 ± 0.93 mm after CT surface marker registration and 1.25 ± 0.64 mm after infrared face scanner registration. The mean target registration errors were 2.95 ± 1.4 mm using fiducial registration and 2.90 ± 1.3 mm using surface registration. The largest deviations (6.2 mm) were found for the targets in the skull base and posterior cranial fossa. Fiducial deviations and target registration errors were statistically uncorrelated. The total application accuracy was 4.87 ± 0.97 mm after CT surface marker registration and 4.14 ± 0.64 mm after infrared face scanner registration. CONCLUSIONS: Despite others have reported differences, we did not find significant variations between both registration methods for the target registration error, although application accuracy was slightly better after surface face registration. Superficial registration errors, but not the target registration error, can be routinely evaluated in the operating room. Since both errors were uncorrelated, surgeons may neglect the achievable accuracy of the procedure. The described method is recommended to assess application accuracy in the operating room.
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Cabeza/cirugía , Procedimientos Neuroquirúrgicos/métodos , Fantasmas de Imagen , Cirugía Asistida por Computador/métodos , Fosa Craneal Posterior/diagnóstico por imagen , Fosa Craneal Posterior/cirugía , Cara/diagnóstico por imagen , Cabeza/diagnóstico por imagen , Humanos , Imagenología Tridimensional , Radiocirugia/métodos , Reproducibilidad de los Resultados , Base del Cráneo/diagnóstico por imagen , Base del Cráneo/cirugía , Tomografía Computarizada por Rayos XRESUMEN
PURPOSE: To evaluate the clinical status and renal function of pa- tients with duplex system and intravesical ureterocele after drainage by cystoscopy. MATERIAL AND METHODS: In 9 patients with duplex system and intravesical ureterocele drainage was performed to present recurrent urinary tract infections (7 children with episodes of pyelonephritis and sepsis) or obstruction of the urinary drainage. The mean age was 33 months (range 8-108 months). The thecnique was done under general anesthesia in the operating room and puncture of the ureterocele was performed using cystourethroscopy with loop electrode. The minimum follow-up was 12 months (range 12-48 months) and includes renal ultrasound, renal isotopic study (Mag3 with furosemide) and-echocystography study in patients with preoperative vesicoureteral reflux or postoperative urinary tract infection. RESULTS: The average operative time was 60 minutes. Mean hospital stay was 48 hours. There were no complications during the procedure. In five patients urinary infection episodes disappeared. Ultrasound demonstrated decreased hydronephrosis and megaureter. In two patients the differential renal function following the technique improved. One patient with preoperative split renal function of 14% required nephrectomy. One patient had postoperative vesicoureteral reflux. CONCLUSIONS: The drainage of intravesical ureterocele in patients with duplex system reduces episodes of urinary tract infection and urinary tract dilation.
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Riñón/anomalías , Uréter/anomalías , Ureterocele/complicaciones , Ureterocele/cirugía , Ureteroscopía , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Estudios RetrospectivosRESUMEN
ABSTRACT: Organizations are learning that efforts to protect the health and safety of their workers from risks both at work and outside of work yield great dividends in the form of increased productivity, morale, and reduced healthcare costs. This realization has given rise to a variety of worker well-being initiatives that span far beyond the typical boundaries of traditional workplace health and safety programs. Examples include providing information and services on diet, exercise, personal habits, and mental health issues. Interestingly, the radiation safety profession has been historically involved with a series of progressive worker well-being practices that perhaps are not fully appreciated by the broader well-being community. These include the ability to comprehensively track occupational doses, training regarding doses arising from outside the workplace (such as medical procedures and environmental exposures), and fetal protection policies, to name a few. Described here is the shift in perspective from health and safety merely for the workplace to a more holistic approach, but the degree to which the actions may be implemented varies. Included then is a compendium of radiation safety practices that may be possibly folded into the discussion of larger organizational well-being efforts.
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Salud Laboral , Protección Radiológica , Protección Radiológica/normas , Humanos , Exposición Profesional/prevención & control , Lugar de Trabajo/organización & administración , Administración de la Seguridad/organización & administración , Traumatismos por Radiación/prevención & controlRESUMEN
BACKGROUND: Pyoderma gangrenosum is a serious cutaneous complication seen in approximately 1 % of patients with inflammatory bowel disease (IBD). Oral corticosteroids are the mainstay treatment, although the evidence supporting their use is weak. AIMS: The purpose of this study was to investigate the characteristics of pyoderma gangrenosum associated with Crohn's disease or ulcerative colitis and which treatments are prescribed in Spanish clinical practice. METHODS: In this retrospective, observational study, the medical records from all patients with IBD and a diagnosis of pyoderma gangrenosum attended by the gastroenterology departments of 12 Spanish hospitals were reviewed. Data on patient demographics and characteristics, underlying IBD and treatment, and pyoderma gangrenosum characteristics, treatment, and outcome were collected and analyzed. RESULTS: The data from 67 patients were analyzed (41 [61.2 %] women, 41 [61.2 %] with Crohn's disease, 25 [37.3 %] with ulcerative colitis, and 1 [1.5 %] with indeterminate disease). The underlying disease was in remission in approximately one-third of patients at the time of presentation of pyoderma gangrenosum. Healing was achieved in all patients (in 3 without any systemic therapy). Oral corticosteroids were taken by 51 patients (76.1 %), almost always as first-line treatment, although definitive healing was attained in 19 (28.4 %). Biologic agents such as infliximab and adalimumab were taken by 31 patients (46.3 %) at some point (first-line in 6 patients [9.0 %]), with definitive healing in 29 patients (93.5 %). CONCLUSIONS: Oral corticosteroid therapy remains the most common treatment for pyoderma gangrenosum associated with inflammatory bowel disease. Biologic therapies such as infliximab and adalimumab should also be considered.
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Colitis Ulcerosa/complicaciones , Enfermedad de Crohn/complicaciones , Enfermedades Inflamatorias del Intestino/complicaciones , Piodermia Gangrenosa/tratamiento farmacológico , Piodermia Gangrenosa/patología , Adalimumab , Administración Oral , Administración Tópica , Corticoesteroides/administración & dosificación , Corticoesteroides/uso terapéutico , Adulto , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/uso terapéutico , Femenino , Humanos , Infliximab , Masculino , Persona de Mediana Edad , Piodermia Gangrenosa/etiología , Estudios Retrospectivos , España , Resultado del TratamientoRESUMEN
Many information processing challenges are difficult to solve with traditional Turing or von Neumann approaches. Implementing unconventional computational methods is therefore essential and optics provides promising opportunities. Here we experimentally demonstrate optical information processing using a nonlinear optoelectronic oscillator subject to delayed feedback. We implement a neuro-inspired concept, called Reservoir Computing, proven to possess universal computational capabilities. We particularly exploit the transient response of a complex dynamical system to an input data stream. We employ spoken digit recognition and time series prediction tasks as benchmarks, achieving competitive processing figures of merit.
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Materiales Biomiméticos , Computadores , Electrónica/instrumentación , Dispositivos Ópticos , Oscilometría/instrumentación , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , FotonesRESUMEN
Herein, we report the formation of organized mesoporous silica materials prepared from a novel nonionic gemini surfactant, myristoyl-end-capped Jeffamine, synthesized from a polyoxyalkyleneamine (ED900). The behavior of the modified Jeffamine in water was first investigated. A direct micellar phase (L(1)) and a hexagonal (H(1)) liquid crystal were found. The structure of the micelles was investigated from the SAXS and the analysis by generalized indirect Fourier transformation, which show that the particles are globular of core-shell type. The myristoyl chains, located at the ends of the amphiphile molecule, are assembled to form the core of the micelles and, as a consequence, the molecules are folded over on themselves. Mesoporous materials were then synthesized from the self-assembly mechanism. The recovered materials were characterized by SAXS measurements, nitrogen adsorption-desorption analysis, and transmission and scanning electron microscopy. The results clearly evidence that by modifying the synthesis parameters, such as the surfactant/silica precursor molar ratio and the hydrothermal conditions, one can control the size and the nanostructuring of the resulting material. It was observed that, the lower the temperature of the hydrothermal treatment, the better the mesopore ordering.
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ABSTRACT: In 1992, the University of Texas Health Science Center at Houston (UTHealth) Radiation Safety Program began assembling data on a monthly basis that described various program drivers and associated activities. A summary of the data was assembled on an annual basis and shared with the professional health physics community at the 10-y and 20-y intervals. With the inclusion of 1991 data points, three decades (1991 to 2020) of data have now been collected and summarized into an updated program prospectus. The prospectus models a commercial enterprise prospectus provided to potential investors and displays various program indicator parameters. The consistent formatting of the data affords an easily digestible and succinct snapshot of program activities and trends. Various program stakeholder's feedback regarding this data continues to be well received. Additionally, UTHealth provides increasing support for UT Physicians clinics throughout the greater Houston, Texas area. The prospectus allows succinct description of the drivers of the program, revealed interesting trends, and has identified training needs for both existing personnel and academic programs that support the radiation protection sciences.
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Protección Radiológica , Física Sanitaria , TexasRESUMEN
ABSTRACT: The onset of the COVID pandemic impacted various regulatory agencies' ability to safely fulfill their regulatory compliance inspection mandates via on-site inspections. Some agencies shifted to a remote or hybrid inspection process, which necessitates the electronic transmittal of a variety of records that may or may not have been transmitted in this fashion in the past, raising concerns about the records being sent and received securely. Considering this new environment, some basic cyber security diagnostic considerations are described for radiation source permit holders to consider prior to responding to an apparent legitimate regulatory inspection request, both in the current COVID cyber risk environment and the environment likely to exist into the future.
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ABSTRACT: The Health Physics Society's stated mission is "excellence in the science and practice of radiation safety." Why, then, should we discuss disease outbreaks, epidemics, and pandemics with radiation safety professionals? The answer is simple: all workers are impacted by infectious diseases-and, as safety professionals, we will inevitably be called upon to prepare for and respond to these events. The COVID-19 pandemic has disrupted every facet of life, including home, school, work, and leisure. Moreover, virtually all radiation safety professionals have been impacted by the pandemic either personally, academically, or professionally. Even if radiation safety professionals were not involved directly with COVID-19 response, they were impacted by school closures, remote schooling and work, testing regimes, temperature screenings, vaccination programs, and so forth. However, many radiation safety professionals have been intimately involved in COVID-19 response through activities such as the deployment of personal protective equipment, directional airflow verification for isolation areas, disinfection and decontamination efforts, the design and layout of testing and vaccine centers, and in many other ways. Yet, it is likely that many radiation safety professionals have not received formal training in epidemiology, disease control, or other related topics, and thus may not be attuned to the key aspects to consider when the next pandemic emerges-and it will.
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COVID-19 , Pandemias , COVID-19/epidemiología , COVID-19/prevención & control , Física Sanitaria , Humanos , Pandemias/prevención & control , Equipo de Protección PersonalRESUMEN
A simple and effective route has been developed for the synthesis of bimodal (3.6 and 9.4 nm) mesoporous silica materials that have two ordered interconnected pore networks. Mesostructures have been prepared through the self-assembly mechanism by using a mixture of polyoxyethylene fluoroalkyl ether and triblock copolymer as building blocks. The investigation of the R(F)(8)(EO)(9)/P123/water phase diagram shows that in the considered surfactant range of concentrations the system is micellar (L(1)). DLS measurements indicate that this micellar phase is composed of two types of micelles; the size of the first one at around 7.6 nm corresponds unambiguously to the pure fluorinated micelles. The second type of micelles at higher diameter consists of fluorinated micelles that have accommodated a weak fraction of P123 molecules. Thus, in this study the bimodal mesoporous silica is really templated by two kinds of micelles.
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Hidrocarburos Fluorados/química , Micelas , Dióxido de Silicio/química , Tamaño de la Partícula , Porosidad , Dióxido de Silicio/síntesis química , Propiedades de SuperficieRESUMEN
BACKGROUND: adalimumab, a human anti-TNF, is an effective induction and maintenance therapy for patients with moderate to severe Crohn's disease. It seems to be effective in patients with resistance to infliximab, too, though the experience is more limited. AIM: to evaluate the efficacy of adalimumab, in patients with Crohn's disease (CD) and failure to previous treatment with infliximab. METHODS: twenty-five patients with CD and failure to previous treatment with infliximab were enrolled; they were treated with 160/80 (24 patients) and 80/40 (1 patient) induction doses. We analyze clinical response to treatment with adalimumab by the Crohn's disease Activity Index (CDAI) and plasma concentration of C-reactive protein (CRP), steroid sparing and complete fistula closure at week 48. RESULTS: eighteen out of twenty-five patients (72%) achieved clinical remission (CDAI score < 150) at week 24 and 15/25 (60%) patients at week 48. There was a statistically significant difference(p < 0.01) in CRP serum levels from 21 to 8 mg/dl at week 48.Nine out of fifteen patients (60%) treated with corticosteroids were able to discontinue steroids. Three out of eleven patients (27%) with fistulizing Crohn's disease had complete fistula closure after the treatment. Seventy two percent of the patients (18/25) needed to increase adalimumab to weekly dose, in order to maintain clinical response. Five out of twenty-five patients (20%) had adverse events; two of them (8%) with serious adverse events (tuberculous meningitis and abdominal abscess) that forced the withdrawal of treatment. CONCLUSIONS: according to these data, adalimumab provides a clinical and analytical improvement in patients with CD and failure to previous therapy with infliximab.
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Antiinflamatorios/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Enfermedad de Crohn/tratamiento farmacológico , Absceso Abdominal/etiología , Adalimumab , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Azatioprina/administración & dosificación , Azatioprina/uso terapéutico , Proteína C-Reactiva/análisis , Enfermedad de Crohn/complicaciones , Susceptibilidad a Enfermedades , Resistencia a Medicamentos , Quimioterapia Combinada , Femenino , Humanos , Infliximab , Fístula Intestinal/tratamiento farmacológico , Fístula Intestinal/etiología , Masculino , Metotrexato/administración & dosificación , Metotrexato/uso terapéutico , Prednisona/administración & dosificación , Prednisona/uso terapéutico , Tuberculosis Meníngea/etiología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidoresRESUMEN
INTRODUCTION: several studies have pointed out the effectiveness of the PillCam colon capsule endoscopy (CCE) compared with the colonoscopy in the study of the colonic pathology. AIMS AND METHODS: the objective of our study was to assess the agreement in the diagnosis of CCE with conventional colonoscopy as well as its sensitivity and specificity, and to describe the findings of the CCE in our clinical practice. Consecutive patients with abdominal symptoms were included in the study. The CCE was performed as previously reported (with PEG and sodium phosphate as laxative agents). The nature and location of the findings, colonic transit time, complications, cleanliness degree and consistency with diagnostic colonoscopy, when performed, were analyzed. RESULTS: a total of 144 subjects (67 women and 77 men); (52.17 ± 16.71 years) with the following indications were included: screening of Colorectal cancer (88 patients), control after polipectomy (24), incomplete colonoscopy (7), rectal bleeding (10), anemia (8), diarrhea (7). The CCE exploration was complete in 134/144 cases (93%), with no case of retention. The preparation was good-very good in 88/134 (65,6%), fair in 26/134 (19,4%) and poor in 20/134 (15%) of the cases. The average colonic transit was of 140.76 min (9-603). Any adverse effect was notified.In 44 cases a colonoscopy was carried out after CCE (results were hidden from another endoscopist). Compared to colonoscopy, the rate of agreement was 75,6%, the sensitivity was 84% and the specificity 62,5%, PPV was 77,7% and NPV was 71,4%.The colonic findings in 134 CCE were: in 34 cases CCE it did not show lesions, diverticulosis in 63 explorations, polyps in 43, angiodysplasias in 15, Crohn's Disease in 9 and ulcerative colitis in other 8 cases. CONCLUSIONS: the CCE is an effective and reliable technique for the detection of lesions in colon, and because of its high agreement with the colonoscopy, it could be useful in clinical practice. Further studies with large seria and cost-effectiveness analysis are needed to confirm these data.
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Endoscopía Capsular/métodos , Colon/patología , Colonoscopía/métodos , Adolescente , Adulto , Anciano , Endoscopios en Cápsulas , Enfermedades del Colon/diagnóstico , Enfermedades del Colon/patología , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/patología , Dieta , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto JovenRESUMEN
UNLABELLED: The surgical treatment of Chiari I malformation is to carry out a suboccipital decompression. It is described that postoperative complications may occur, especially if the dura is open and closed using a graft (duraplasty). Among them, one of the most important events due to its difficult handling is cerebrospinal fluid leak through the suture line. OBJECTIVE: To conduct a postoperative review to analyze the outcome of the patients and the occurrence of complications depending on the dural plasty used. MATERIAL AND METHODS: A retrospective study was carried out between 1997 and 2008, both inclusive, where we assessed 36 patients. All of them were studied with preoperative and postoperative craniospinal magnetic resonance, and by a thorough clinical examination performed before and after the surgery. The surgical procedure consisted of suboccipital decompression and resection of the posterior arch of C1 or C1 and C2 (depending on the extent of the caudal displacement of the tonsils), followed by duraplasty using either an autologous graft (pericranium) or a synthetic graft (Gore-tex). RESULTS: After a mean follow-up of 2 years, the clinical results were: excellent (55%), if there was a great clinical improvement; good (29%), if there was slight improvement; and bad (16%), if there was no improvement or there was worsening. In the 30 patients given a duraplasty (18 with an artificial graft, 12 with an autologous pericranium graft), 6 cases of cerebrospinal fluid leak appeared, although no significant association between the type of dural plasty and the presence of leak was observed. CONCLUSIONS: The best results were obtained for headaches, cervical pain and dizziness. Despite the fact that there were more cases of cerebrospinal fluid leak in patients receiving an artificial graft compared to patients with pericranium graft, there was no significant difference.
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Malformación de Arnold-Chiari/cirugía , Descompresión Quirúrgica/efectos adversos , Duramadre/cirugía , Complicaciones Posoperatorias , Adulto , Anciano , Pérdida de Líquido Cefalorraquídeo , Rinorrea de Líquido Cefalorraquídeo/etiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Trasplantes/efectos adversos , Resultado del Tratamiento , Adulto JovenRESUMEN
NiWO4 with a volumetric storage density (VSD) of 496 g L-1 was studied to evaluate its H2 storage potential as an oxygen carrier under a chemical looping (CL) process scheme. The material was synthesized by precipitation and calcined at 950 °C for 5 hours in air. Characterization consisted in XRD, BET surface area, SEM and EDS analysis. NiWO4 hydrogen storage reduction-oxidation evaluation was performed by TGA using 5% v H2/Ar and 2.2% v H2O/Ar at 800 °C. Global kinetics for the reduction step was studied from 730 to 870 °C using 2 to 5% v of H2/Ar. While oxidation kinetics was examined from 730 to 870 °C using 0.8 to 2.2% v H2O/Ar. A hydrogen storage multicycle stability test was performed by exposing NiWO4 to 17 consecutive redox cycles. XRD results of the synthesized material indicate NiWO4 as the only crystalline phase. Fully reduced material found only W and Ni species, while reoxidation led back to NiWO4. BET surface area of synthesized material was 4.25 m2 g-1. SEM results showed fresh NiWO4 composed of non-porous large particles (1-5 µm). After reduction, the material shown a porous coral-like morphology with particles between 50 to 100 nm. EDS analysis results confirmed the compositions of the reduced (Ni + W) and fully oxidized NiWO4 species, respectively. Oxygen carrier reaction conversions for both reduction and regeneration steps were 100%. Global kinetic studies indicate a first order reaction for the two reduction steps and during oxidation, with activation energies of 22.1, 48.4 and 53.4 kJ mol-1 for the two reduction and oxidation steps, respectively. NiWO4 multicycle stability test shown no loss of VSD and fast reduction and oxidation kinetics under the studied conditions after seventeen consecutive redox cycles, which confirms the potential of this material with respect to current oxygen carriers reported in the literature for hydrogen storage applications.
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INTRODUCTION AND AIM: Hepatocellular carcinoma (HCC) is the most frequent primary tumor of the liver. HCC in the noncirrhotic liver accounts for 15-20% of all HCC. Noncirrhotic HCC is a clinically different entity because of the non-neoplastic liver parenchyma involved. Our aim was to describe the presentation, treatment, and predictive survival results of noncirrhotic HCC in Veracruz. MATERIAL AND METHOD: A retrospective study, spanning 13 years, was conducted on patients with noncirrhotic HCC. It analyzed their clinical characteristics, fibrosis/cirrhosis biologic index (NAFLD, MELD, ALBI, APRI, CDS, FIB-4, GUCI, Lok) results, disease treatment, and survival. RESULTS: From a total of 168 cases of HCC, 33 (19.6%) noncirrhotic patients were included in the study. Of those patients, the mean patient age was 67.3 years (51.5% men), 9.1% had hepatitis C virus infection, and 27.3% were alcoholics. Less than 20% of the patients had biologic indexes suggestive of fibrosis/cirrhosis. Mean tumor size was 7.7cm and 42.4% of the patients had alpha-fetoprotein levels>15ng/ml. A total of 52.5% of the tumors were classified as Okuda II and 30.3% of the patients had advanced disease (the Milan criteria). Liver resection was performed on 51.5% of the patients, radiofrequency ablation on 18.2%, and transarterial chemoembolization on 9.1%. The overall 5-year survival rate was 55.4%. Liver resection resulted in the best 5-year survival rate (72.7%). Age>67 years and elevated alpha-fetoprotein levels were associated with poorer survival (P<.05, log-rank). CONCLUSIONS: The characteristics and survival rate of HCC in the noncirrhotic liver were similar to those reported in other studies. Liver resection provided the highest survival rates. The liver fibrosis biologic indexes were not risk factors for survival.
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Convergent evolution provides insights into the selective drivers underlying evolutionary change. Snake venoms, with a direct genetic basis and clearly defined functional phenotype, provide a model system for exploring the repeated evolution of adaptations. While snakes use venom primarily for predation, and venom composition often reflects diet specificity, three lineages of cobras have independently evolved the ability to spit venom at adversaries. Using gene, protein, and functional analyses, we show that the three spitting lineages possess venoms characterized by an up-regulation of phospholipase A2 (PLA2) toxins, which potentiate the action of preexisting venom cytotoxins to activate mammalian sensory neurons and cause enhanced pain. These repeated independent changes provide a fascinating example of convergent evolution across multiple phenotypic levels driven by selection for defense.