Differentiation of white matter histopathology using b-tensor encoding and machine learning.

Diffusion-weighted magnetic resonance imaging (DW-MRI) is a non-invasive technique that is sensitive to microstructural geometry in neural tissue and is useful for the detection of neuropathology in research and clinical settings. Tensor-valued diffusion encoding schemes (b-tensor) have been developed to enrich the microstructural data that can be obtained through DW-MRI. These advanced methods have proven to be more specific to microstructural properties than conventional DW-MRI acquisitions. Additionally, machine learning methods are particularly useful for the study of multidimensional data sets. In this work, we have tested the reach of b-tensor encoding data analyses with machine learning in different histopathological scenarios. We achieved this in three steps: 1) We induced different levels of white matter damage in rodent optic nerves. 2) We obtained ex vivo DW-MRI data with b-tensor encoding schemes and calculated quantitative metrics using Q-space trajectory imaging. 3) We used a machine learning model to identify the main contributing features and built a voxel-wise probabilistic classification map of histological damage. Our results show that this model is sensitive to characteristics of microstructural damage. In conclusion, b-tensor encoded DW-MRI data analyzed with machine learning methods, have the potential to be further developed for the detection of histopathology and neurodegeneration.

Quantification and enantiomeric distribution of clenbuterol in several bovine tissues using UHPLC-tandem mass spectrometry: Evaluation of a risk factor associated with meat contamination.

Clenbuterol (Clb) (4-amino-α-[(tert-butylamine) methyl]-3,5-dichlorobenzyl alcohol) is a sympathomimetic agent that exhibits ß2-agonist activity. It is applied as a bronchodilatory, tocolytic, and mucolytic agent and is authorized for clinical management in both human and veterinary therapeutics as a racemic mixture. However, its use is strictly prohibited in animals destined for food production in countries in the European Union and in the United States and Mexico, among many others. The R-(-) enantiomer in clenbuterol stimulates ß2-receptors, whereas the S-(+) enantiomer blocks the effect of ß1-receptors. The aims of this study were to develop a method for detecting and quantifying Clb and its enantiomeric distribution in several bovine tissues. The UHPLC-MS/MS method developed to quantify the target compound at trace levels in these tissues combines high sensitivity with good selectivity and short chromatographic run time. The tissue samples tested were found to contain racemic Clb in concentrations of 5-447 pg g-1 . The enantiomeric analysis of Clb showed that R-(-)-Clb is present at higher concentrations in some tissues, whereas S-(+)-Clb was detected in a ratio of 55/45 in the liver and heart tissues.

GABB: A global dataset of alpine breeding birds and their ecological traits.

Alpine ecosystems represent varied climates and vegetation structures globally, with the potential to support rich and functionally diverse avian communities. High mountain habitats and species are under significant threat from climate change and other anthropogenic factors. Yet, no global database of alpine birds exists, with most mountain systems lacking basic information on species breeding in alpine habitats, their status and trends, or potential cryptic diversity (i.e., sub-species distributions). To address these critical knowledge gaps, we combined published literature, regional monitoring schemes, and expert knowledge from often inaccessible, data-deficient mountain ranges to develop a global list of alpine breeding bird species with their associated distributions and select ecological traits. This dataset compiles alpine breeding records for 1,310 birds, representing 12.0% of extant species and covering all major mountain regions across each continent, excluding Antarctica. The Global Alpine Breeding Bird dataset (GABB) is an essential resource for research on the ecological and evolutionary factors shaping alpine communities, as well as documenting the value of these high elevation, climate-sensitive habitats for conserving biodiversity.

Detection of clenbuterol residues in beef sausages and its enantiomeric analysis using UHPLC-MS/MS: A risk of unintentional doping in sport field.

Clenbuterol (Clb) can be present in Mexico often but not all over the world in animal tissues and organs, therefore, potentially is derived from animal sources as well. The aims of this study were to develop and validate a method for detecting traces of clenbuterol in beef sausages. A calibration curve showed linearity in the range of 20-500 pg ml-1 . The limit of detection (LOD) and lower limit of quantification (LLOQ) were 5 and 10 pg g-1 , respectively. The analyte recovery was from 95.70% to 100.40% with an intraday relative standard deviation (RSD%) of 0.99%-2.10% and an interday RSD% of 0.54%-2.34%, R2 = 0.9998. The methodology developed was applied successfully in 15 samples of beef sausage, and 73.3% of the samples tested contained racemic clenbuterol in concentrations between 30 and 471 pg g-1 . The UHPLC-MS/MS method developed combines high sensitivity with good selectivity and short chromatographic run time. Additionally, the enantiomeric analysis of clenbuterol performed in beef sausages showed a 59% for R-(-)-Clb and 41% for S-(+)-Clb. The presence of clenbuterol in beef sausages could represent a risk of unintentional doping in sport field, because the clenbuterol is a banned substance included in the World Anti-Doping Agency's (WADA) list of prohibited substances.

Assembly principle of a membrane-anchored nuclear pore basket scaffold.

Nuclear pore complexes (NPCs) are membrane-embedded gatekeepers of traffic between the nucleus and cytoplasm. Key features of the NPC symmetric core have been elucidated, but little is known about the NPC basket, a prominent structure with numerous roles in gene expression. Studying the basket was hampered by its instability and connection to the inner nuclear membrane (INM). Here, we reveal the assembly principle of the yeast NPC basket by reconstituting a recombinant Nup60-Mlp1-Nup2 scaffold on a synthetic membrane. Nup60 serves as the basket's flexible suspension cable, harboring an array of short linear motifs (SLiMs). These bind multivalently to the INM, the coiled-coil protein Mlp1, the FG-nucleoporin Nup2, and the NPC core. We suggest that SLiMs, embedded in disordered regions, allow the basket to adapt its structure in response to bulky cargo and changes in gene expression. Our study opens avenues for the higher-order reconstitution of basket-anchored NPC assemblies on membranes.

Determination of clenbuterol at trace levels in raw gelatin powder and jellies using ultra-high-performance liquid chromatography coupled to triple quadrupole mass spectrometry.

Clenbuterol is present in animal tissues and organs and, therefore, potentially present in gelatin derived from animal sources. The objective of this study was to develop a method for identify an quantify traces of clenbuterol in gelatin and jellies. The clenbuterol calibration curve showed linearity in the range of 20-1000 pg mL-1. The detection and quantification limits were 5 pg g-1 and 10 pg g-1, respectively. The recovery of the analyte ranged from 93.4 to 98.7% with an intra-day RSD% (n = 4) of 1.25%-3.25%, and an inter-day RSD% (n = 12) of 0.5%-2.25%, with good linearity (R2 = 0.99). The method developed and validated was successfully applied in 54 gelatin samples, 57.4% of which showed clenbuterol. This UHPLC-MS/MS method combines high sensitivity with good selectivity and short chromatographic run time.

3D Simulation-Based Acoustic Wave Resonator Analysis and Validation Using Novel Finite Element Method Software.

This work illustrates the analysis of Film Bulk Acoustic Resonators (FBAR) using 3D Finite Element (FEM) simulations with the software OnScale in order to predict and improve resonator performance and quality before manufacturing. This kind of analysis minimizes manufacturing cycles by reducing design time with 3D simulations running on High-Performance Computing (HPC) cloud services. It also enables the identification of manufacturing effects on device performance. The simulation results are compared and validated with a manufactured FBAR device, previously reported, to further highlight the usefulness and advantages of the 3D simulations-based design process. In the 3D simulation results, some analysis challenges, like boundary condition definitions, mesh tuning, loss source tracing, and device quality estimations, were studied. Hence, it is possible to highlight that modern FEM solvers, like OnScale enable unprecedented FBAR analysis and design optimization.

Phase separation directs ubiquitination of gene-body nucleosomes.

The conserved yeast E3 ubiquitin ligase Bre1 and its partner, the E2 ubiquitin-conjugating enzyme Rad6, monoubiquitinate histone H2B across gene bodies during the transcription cycle1. Although processive ubiquitination might-in principle-arise from Bre1 and Rad6 travelling with RNA polymerase II2, the mechanism of H2B ubiquitination across genic nucleosomes remains unclear. Here we implicate liquid-liquid phase separation3 as the underlying mechanism. Biochemical reconstitution shows that Bre1 binds the scaffold protein Lge1, which possesses an intrinsically disordered region that phase-separates via multivalent interactions. The resulting condensates comprise a core of Lge1 encapsulated by an outer catalytic shell of Bre1. This layered liquid recruits Rad6 and the nucleosomal substrate, which accelerates the ubiquitination of H2B. In vivo, the condensate-forming region of Lge1 is required to ubiquitinate H2B in gene bodies beyond the +1 nucleosome. Our data suggest that layered condensates of histone-modifying enzymes generate chromatin-associated 'reaction chambers', with augmented catalytic activity along gene bodies. Equivalent processes may occur in human cells, and cause neurological disease when impaired.

Quantification and Stereochemical Composition of R-(-) and S-(+)-Clenbuterol Enantiomers in Bovine Urine by Liquid Chromatography-Tandem Mass Spectrometry.

Clenbuterol (4-amino-α-[(tert-butylamino)methyl]-3,5-dichlorobenzylalcohol) is a ß2-adrenergic agonist. The consumption of meat contaminated with clenbuterol can lead to increased heart rate, blood pressure, anxiety, palpitations and skeletal muscle tremors. Several analytical methods have been developed to identify and quantify clenbuterol in different biological matrices. In this report, we have developed a specific and sensitive analytical method for quantifying clenbuterol and performed an in-depth enantiomeric analysis in bovine urine. The method was evaluated in accordance with international guidelines, and we used an isotopically labeled analog as an internal standard. The extraction efficiency for clenbuterol in bovine urine was > 98%, the limit of detection was 0.05 ng/mL and the limit of quantification was 0.10 ng/mL. Our assay showed high specificity, no carryover was observed and the assay was linear in the range 0.10-8.0 ng/mL. Fifteen bovine urine samples were analyzed (containing clenbuterol), and an enantiomeric analysis was performed. The clenbuterol concentration range was 0.10-10.56 ng/mL across these samples. The levorotatory enantiomer was detected at greater concentrations than the dextrorotatory enantiomer, the ratio being 1.7 ± 0.6 (n = 15), and a statistical difference was observed (P < 0.05) using the Wilcoxon test.

Small-Bowel Obstruction Secondary to Ileal Trichobezoar in a Patient with Rapunzel Syndrome.

Bezoars are conglomerations of undigested foreign material retained in the gastrointestinal tract. Trichobezoar is a compact conglomeration of swallowed hair and constitutes less than 6% of all bezoars. Their most frequent location is in the stomach but they may extend through the pylorus into the small bowel. This condition is known as Rapunzel syndrome. Many patients may remain asymptomatic or present a mild form of the disease characterized by abdominal pain, early satiety, nausea, and vomiting. Complications may manifest as gastric outlet obstruction or bleeding, and intestinal obstruction. A 15-year-old female patient presented with clinical findings of intestinal obstruction. The patient suffered from depressive and anxiety disorders and trichotillomania, although trichophagy could not be assured. Alopecia circumscripta and irregular hair length on the scalp were identified. A computed tomography (CT) scan showed two images highly suggestive of trichobezoars, one in the stomach and the second one causing obstruction at the ileocecal valve. At laparotomy, both a mobile gastric trichobezoar with a tail extending to the duodenum and a trichobezoar causing obstruction at the ileocecal valve were removed. The postoperative course was uneventful. The passage of a detached trichobezoar fragment in a patient with Rapunzel syndrome may cause intestinal obstruction. CT is the preferred image modality for the evaluation of suspected trichobezoars in order to characterize their size and locations, the presence and level of obstruction, and complications such as ischemia or perforation. A case of small-bowel obstruction secondary to ileal trichobezoar in a patient with Rapunzel syndrome is herein reported.

Pacientes pediátricos con VIH/sida en Baja California, México: alteraciones bucales relacionadas / Pediatric patients with HIV/AIDS in Baja California, Mexico: oral disorders related

Antecedentes: Baja California, México, ocupa el cuarto lugar nacional en casos reportados de VIH/sida. Por ser los pacientes pediátricos la población más vulnerable, el odontólogo debe diagnosticarlos y canalizarlos oportunamente para una adecuada atención. Objetivo: describir las alteraciones dentales y de mucosa oral asociadas más frecuentes en pacientespediátricos con diagnóstico de VIH/sida en Baja California. Metodología: se realizó un estudioclínico de corte transversal a pacientes pediátricos diagnosticados antes de los 12 años de edad, registrados en los Departamentos de Epidemiología del estado hasta agosto del 2006. Se aplicó un cuestionario para registrar variables sociodemográficas, antecedentes heredofamiliares, patológicos, concentraciones de CD4 y cargas virales. Posteriormente, demanera calibrada y siguiendo los índices establecidos por la OMS, se realizó exploración intraoral y de estructuras extraorales. Cuando se identificó la presencia de manifestaciones orales asociadas al VIH/sida, se realizaron frotis. Resultados: se revisaron 46 pacientes VIH positivos, con edad media de 6,4 ± 4,4 años, 57% de sexo masculino, 50% en categoríaclínica sintomática ligera y 67% sin supresión, 50% tenía antecedentes de hospitalizaciones por enfermedades como tuberculosis y neumonía, 63% presentaba caries y 44% lesionesen la mucosa oral, siendo la candidosis oral la de mayor frecuencia. El índice CPO-d fue de 5,2 ± 4,9. Conclusiones: este estudio describe lesiones orales en una población infantil condiagnóstico de VIH/sida en Baja California. Ya que no existen estudios previos, el valor del trabajo radica en que aporta información para el desarrollo de programas odontológicos y provee una base de comparación para futuros trabajos...

Background: Baja California, Mexico, ranks fourth nationally in reported cases of HIV/AIDS. Since paediatric patients are the most vulnerable population, the dentist must do awell-timed diagnosis and channel them for adequate care. Objective: To describe the most frequent dental and oral mucosa alterations associated with HIV/AIDS in diagnosed pediatricpatients from Baja California. Methods: A cross-sectional clinical study was carried out with pediatric patients diagnosed with HIV/AID before age 12, who were registered atEpidemiology Departments of the state until August 2006. A questionnaire including sociodemographic variables, family history, pathology, CD4 and viral load levels was applied. Later, calibrated observers registering the indicators determined by the WHO performed intraoral and extraoral examination. When an oral alteration associated with HIV/AIDS was identified, tissues smears were obtained. Results: 46 HIV positive patients with a mean of 6.4 ± 4.4 years of age were examined. 57% were male, 50% were in light symptomatic clinical category and 67% did not have suppression, 50% reported a history of hospitalizations for diseases such as Tuberculosis and Pneumonia, 63% had caries and 44% oral mucosal lesions, of which oral candidiasis was the most frequent. The DMF-T index was 5.2 ± 4.9. Conclusion: The population studied presented lesions associated with HIV/AIDS; they may be markers of immune status in which they are, so that immediate oral care, supervision and monitoring must accompany immunosuppression therapy...

Cuidados en el tratamiento odontológico de pacientes pediátricos cardiópatas con transposición de grandes vasos: reporte de un caso / Care in the dental treatment of pediatric heart patients with transposition of the creat vessels: a case report

En este artículo se reporta el caso de un paciente de 12 años de edad, con una cardiopatía congénita conocida como transposición de grandes vasos, quien se presenta a consulta en la Clínica de Odontopediatría de la Facultad de Odontología de la Universidad de Baja California en Mexicali, México, para quien se estableció un protocolo de atencióncon interconsulta con el médico cardiólogo que lo atendió, así como con especialistas en periodoncia y odontopediatría. Para prevenir la endocarditis bacteriana se recomendó la profilaxis antibiótica en cada cita, administrándole clindamicina (600 mg) dos horas antes del procedimiento dental y posteriormente una tableta cada ocho horas durante siete días.Localmente, en cada cita se le administró mepivacaína al 1% como anestésico local, para su tratamiento periodontal y dental. Normalmente, los pacientes cardiópatas con antecedenteshospitalarios requieren una atención especial del odontopediatra en el control de la conducta en cualquier tipo de tratamiento dental...

This article reports the case of a 12-year-old patient who suffered from a congenital heart disease known as transposition of the great vessels, and attended the pediatric dental careservice at the Baja California University Dental School in Mexicali, Mexico. Treatment was planned based on consultation with the cardiologist, the periodontist, and the pediatric dentist. To prevent the risk of bacterial endocarditis, 600 mg clindamycin 2 hours before the dental procedures and 1 tablet every 8 hours for seven days afterwards was prescribed.1% mepivacaine was used as local anesthetic to perform periodontal and dental therapy. Usually, heart patients with history of hospitalization require special behavior management by the pediatric dentist for any kind of dental treatment...

Rehabilitación oral de un paciente pediátrico con síndrome de Smith-Lemli-Opitz bajo anestesia general ambulatoria / Oral rehabilitation of a pediatric patient with smith-lemli-opitz syndrome under outpatient general anesthesia

El síndrome de Smith-Lemli-Opitz es una rara enfermedad hereditaria de transmisión autosómica recesiva. Se caracteriza por presenta hipocolesterolemia como consecuenciade una mutación del gen 7-deshidrocolesterol reductasa (7DHCR), lo que produce retrasomental, retardo en el crecimiento, microcefalia, micrognatismo y otras anomalías neurológicas sistémicas y físicas. Se presenta el caso de un paciente de tres años y nueve mesesafectado por este síndrome, quien acudió a la clínica de odontología pediátrica de la Facultad de Odontología de la Universidad Autónoma de Baja California, Tijuana, donde se inició historia médica y dental. Debido a su corta edad, la presencia de múltiples lesiones cariosas, conducta incontrolable, retraso mental y compromiso sistémico, se decidió realizar larehabilitación oral del paciente bajo anestesia general, la cual se describe detalladamente...

Smith-Lemli-Opitz syndrome is a rare autosomal recessive hereditary disease. It is caused by a mutation in the 7-dehydrocholesterol reductase (DHCR7) gene producing hypocholesterolemia,and consequence mental retardation, delayed growth, microcephaly, micrognathia and other systemic neurological and physical features. A case of a three-year-ninemonth-old patient affected by this syndrome who attended the Pediatric Dental Clinic of the Universidad Autónoma de Baja California Dental School at Tijuana is presented. Afterdoing medical and dental records and because of his young age, multiple dental cavities, uncontrollable behavior, mental retardation and medical status, oral rehabilitation under general anesthesia was performed. The anesthesia procedure is detailed...

Síndrome de Papillon-Lefèvre: reporte de un caso clínico / Papillon-Lefèvre syndrome: report of a clinical case

En este artículo se describe el caso de una paciente de seis años de edad diagnosticada con el síndrome de Papillon-Lefèvre, una rara enfermedad hereditaria de transmisión autosómica recesiva y de etiología desconocida. La paciente presentaba hiperqueratosispalmoplantar. La principal manifestación oral es una periodontitis agresiva que hace que se pierda la dentición primaria y, antes de los quince años de edad, generalmente, sufra la pérdida de su dentición permanente. Los tratamientos generalmente son paliativos yprotésicos desde la infancia...

A case of a six-year-old female patient with a diagnosis of Papillon-Lefèvre syndrome is described. This is a rare hereditary autosomal recessive disease with unknown etiology. The patient presented palmoplantar hyperkeratosis. The main oral manifestation is an aggressiveperiodontitis that causes the patient to lose their deciduous teeth and before the age of fifteen, to lose the permanent dentition. Treatment is generally palliative and prostheticstarting at early age...

Ha perdido la profesión odontológica la batalla contra la caries dental o ha perdido el rumbo: análisis de la situación en México / Has the dental profession lost the battle against tooth decay or has it lost its way: analysis of the situation in Mexico

Objetivo: se presenta un estudio retrospectivo con base en la bibliografía existente de losúltimos cuarenta años acerca de la odontología en México y su contribución a la salud bucodentalen la población, sobre todo en relación con la caries dental. Métodos: se revisarontres aspectos principales: la formación odontológica en escuelas y facultades del país, elservicio de las instituciones públicas de salud y la atención a la población desde la prácticaodontológica privada. Se analizó la bibliografía existente de investigadores mexicanosdesde 1970 hasta el 2011. Resultados: en este análisis se observa una falta de planeaciónpara la creación de escuelas y facultades de odontología, sustentada en las necesidadesreales de la población. Además, es notable la ausencia de un organismo rector que unifiquelos objetivos para la formación de odontólogos en las 120 escuelas existentes en México.Del mismo modo, se observan la falta de desarrollo de la función preventiva de las institucionesde salud, que trabajan con el mismo modelo de servicio de cuando fueron creadas,y una educación odontológica carente de planeación y una normatividad actualizada parala formación de recursos humanos. Conclusión: todo esto se traduce en una profesión quepractica principalmente una actividad centrada en atacar las lesiones y no la enfermedad y,mucho menos, en aplicar acciones para prevenirla. Ello ha propiciado una competencia porun mercado de pacientes que puedan pagar los servicios, pero no ha contribuido a mejorarla salud bucal de la población...

Aim: A retrospective study based on a literature review about dentistry in Mexico and itsimpact on the population’s dental health, with a special focus on dental caries, is presented.Methods: Three main areas were reviewed: training of dentists in Mexican dental schools;dental health care in public institutions, and dental care in the private dental practice. Publicationsfrom 1970 to 2011 by Mexican researchers were analyzed. Results: In this analysis itis noted that there is a lack of planning for the creation of dental schools, in relation to thedental care needs of the population. Besides that, there is an absence of a governing bodythat unifies the objectives for the training of dentists in the 120 existing schools in Mexico,as well as an obsolete preventative role of health care institutions, which work with a healthcare model that has not changed since they were created. There is also a lack of planningand updated regulations for the training and formation of human resources in dentalschools. Conclusions: All this translates into a profession whose practice is mostly focusedon attacking the injuries, not the disease, and much less attention is given to implementactions in preventive dentistry. This has led to a competition for a market of patients whocan afford their services, but has not contributed to improve dental health in the population...

Flujo y capacidad amortiguadora salival en dos grupos de sujetos de 6 a 11 años de edad con bajo y alto índice de dientes cariados, perdidos y obturados / Salivary flow and buffer capacity in two 6-to-11-year-old groups of subjects with low and high decayed, missing and filled teeth index

Objetivo: comprobar la relación entre el flujo y la capacidad amortiguadora salival con la experiencia de caries, en niños con bajo y alto índice de dientes cariados, perdidos y obturados (CPOD). Método: Se realizó un estudio descriptivo transversal a un grupo de 60 niños de 6 a 11 años de edad, de ambos sexos, admitidos para consulta en la Clínica de Admisión de la Facultad de Odontología de la Universidad Autónoma de Baja California, sede Mexicali. Se establecieron dos grupos en función del CPOD: grupo 1 (puntuación 0-3) y grupo 2 (4 o más). Se elaboró una historia clínica que incluyó tanto los datos generales del niño como el registro de la experiencia de caries bajo los criterios de la Organización Mundial de la Salud. Asimismo, se midieron y registraron el volumen de saliva estimulada y la capacidad amortiguadorapara cada sujeto. Resultados: se observó una correlación negativa (r=–0,221) entre el flujo salival y el CPOD; sin embargo, esta tendencia no fue estadísticamente significativa (p>0,05). En cuanto a la capacidad amortiguadora, se hallaron diferencias estadísticamente significativas al relacionar una mayor capacidad amortiguadora y un CPOD bajo (p<0,05). Conclusión: la mayor capacidad amortiguadora de la saliva se relacionó con la menor experiencia de caries. Por su parte, el flujo salival estimulado mostró alguna asociación descriptivamente con el CPOD, pero dicha asociación no fue estadísticamente significativa.

Objective: Demonstrate the association between salivary flow and buffer capacity with caries experience in children with low and high Decayed, Missing and Filled Teeth Index (DMFT). Methods: A cross-sectional study was conducted with 60 6-to-11-year-old children of both sexes, who attended the Dental School of Universidad Autónoma de Baja California, Mexicali campus. The patients were assigned to two groups according to the DMFT score, group 1 (score 0-3) and group 2 (score 4 or more). A clinical record including patient’s general information and dental evaluation was filled out. Cavity experience evaluation was carried out following WHO parameters. Also, salivary flow and buffer capacity were measured in each individual. Results: A weak negative correlation between salivary flow and DMFT score was observed (r=–0.221); however, this trend was not statistically significant (p>0.05). Regarding the buffer capacity, statistically significant differences between this salivary property and DMFT were found (p<0.05). Conclusion: The buffer capacity of saliva was associated with lower caries experience. On the other side, stimulated salivary flow show was not found to be related with the DMFT score.

[Quality of life specific questionnaire for constipated patients: development and validation of CVE-20]. / Cuestionario específico de calidad de vida para pacientes con estreñimiento: desarrollo y validación del CVE-20.

BACKGROUND AND OBJECTIVE: Although constipation affects quality of life, questionnaires hardly exist for its evaluation. We aimed to develop and validate a questionnaire able to measure the quality of life in patients with constipation. PATIENTS AND METHOD: A Spanish multicenter study was performed in 2 stages: a) questionnaire development (open interview to patients with constipation, pilot questionnaire, quantitative and factorial analysis, Rasch analysis, and specific questionnaire design), and b) questionnaire validation in 136 patients. These patients were divided in 2 groups: a) reliability group (n = 55; no need to begin or change treatment; re-tested after 15 days), and b) sensibility to change group (n = 81; need to begin or change treatment; re-tested after 3 months). We collected clinical and socio-demographic data and we evaluated the quality of life through the general questionnaire EuroQoL-5D (EQ-5D) and the specific one, design in the previous stage (25 items). After that, we analysed feasibility, reliability and validity (of content, convergent and longitudinal). RESULTS: The trial questionnaire was obtained during the development stage and the results were 51 items that were later reduced to 25 in the validation stage. A total of 126 patients (93% women; mean age [standard deviation]: 43.4 [1] years) completed the study properly. The answer average time was 12 min. The content validity process reduced the questionnaire to 20 items (CVE-20) within 4 domains: emotional, general physical, rectal physical and social. The reliability was good in relation to the general punctuation (Cronbach alpha coefficient = 0.87), being in the different domains of 0.79, 0.73, 0.75 and 0.60, respectively. The construct validity showed a good correlation between the CVE-20 results and constipation severity. The CVE-20 score positively correlated with EQ -5D changes. The test and re-test reliability were good: interclass correlation coefficient = 0.89 (ranging from 0.80 to 0.88 in the different domains). The clinically relevant and minimal difference was 17 points (95% confidence interval, 11-23). The content validity showed a strong correlation between CVE-20 and constipation severity. CONCLUSIONS: The CVE-20 is the first specific questionnaire in Spanish language for constipated patients; it is valid, reliable, sensitive to changes and it meets the psychometric requirements to be applied in daily practice and clinical trials.

Genoma: presente y futuro / Genome: present and future

Aristóteles, hace 2300 años, dijo que el "concepto" de pollo está implícito en el huevo y que una bellota estaba literalmente "informada" por el plan de una encina. Mucho tiempo después un investigador, Mx Delbruck, decía en broma que se debería conceder un Premio Nobel póstumo al filósofo griego por el descubrimiento del ADN. En efecto Aristóteles, con esos argumentos, confusamente percibió que "la información" estaba en la base de la biología; es decir, de los seres vivos, plantas y animales. Y así es, en realidad: el filamento de ADN es información, es un mensaje escrito en un código de sustancias químicas; además, el lenguaje que utiliza es sencillo y consta de cuatro letras conocidas convencionalmente como A, C, G y T. El ADN es el instrumento de la vida. Hay que señalar dos de sus características esenciales: su capacidad para replicarse y su capacidad de crear orden. Las cosas vivas, plantas y animales producen copias aproximadas de sí mismas; por ejemplo: las semillas del maíz producen más plantas de maíz y el óvulo fecundado de un conejo lleva las instrucciones para componer un nuevo conejo. De otra parte, la capacidad de crear orden corresponde el metabolismo; este es un proceso universal, similar en toda la biodiversidad. Como corolario cabe afirmar lo siguiente: un conejo adulto (todo ser vivo), tanto con su capacidad de reproducirse como de metabolizar, está prefigurado en su código genético. Los genes son, pues, recetas codificadas; en los filamentos (ADN) está prefgurado todo ser viviente.