RESUMEN
Mammalian oocytes are filled with poorly understood structures called cytoplasmic lattices. First discovered in the 1960s and speculated to correspond to mammalian yolk, ribosomal arrays, or intermediate filaments, their function has remained enigmatic to date. Here, we show that cytoplasmic lattices are sites where oocytes store essential proteins for early embryonic development. Using super-resolution light microscopy and cryoelectron tomography, we show that cytoplasmic lattices are composed of filaments with a high surface area, which contain PADI6 and subcortical maternal complex proteins. The lattices associate with many proteins critical for embryonic development, including proteins that control epigenetic reprogramming of the preimplantation embryo. Loss of cytoplasmic lattices by knocking out PADI6 or the subcortical maternal complex prevents the accumulation of these proteins and results in early embryonic arrest. Our work suggests that cytoplasmic lattices enrich maternally provided proteins to prevent their premature degradation and cellular activity, thereby enabling early mammalian development.
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Oocitos , Proteínas , Embarazo , Animales , Femenino , Oocitos/metabolismo , Proteínas/metabolismo , Embrión de Mamíferos/metabolismo , Citoesqueleto , Ribosomas , Desarrollo Embrionario , MamíferosRESUMEN
Arabidopsis thaliana diverged from A. arenosa and A. lyrata at least 6 million years ago. The three species differ by genome-wide polymorphisms and morphological traits. The species are to a high degree reproductively isolated, but hybridization barriers are incomplete. A special type of hybridization barrier is based on the triploid endosperm of the seed, where embryo lethality is caused by endosperm failure to support the developing embryo. The MADS-box type I family of transcription factors is specifically expressed in the endosperm and has been proposed to play a role in endosperm-based hybridization barriers. The gene family is well known for its high evolutionary duplication rate, as well as being regulated by genomic imprinting. Here we address MADS-box type I gene family evolution and the role of type I genes in the context of hybridization. Using two de-novo assembled and annotated chromosome-level genomes of A. arenosa and A. lyrata ssp. petraea we analyzed the MADS-box type I gene family in Arabidopsis to predict orthologs, copy number, and structural genomic variation related to the type I loci. Our findings were compared to gene expression profiles sampled before and after the transition to endosperm cellularization in order to investigate the involvement of MADS-box type I loci in endosperm-based hybridization barriers. We observed substantial differences in type-I expression in the endosperm of A. arenosa and A. lyrata ssp. petraea, suggesting a genetic cause for the endosperm-based hybridization barrier between A. arenosa and A. lyrata ssp. petraea.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Endospermo/genética , Endospermo/metabolismo , Semillas/genética , Factores de Transcripción/metabolismo , Proteínas de Dominio MADS/genética , Proteínas de Dominio MADS/metabolismo , Regulación de la Expresión Génica de las Plantas/genéticaRESUMEN
OBJECTIVE: To translate and evaluate the validity of the Participation Assessment with Recombined Tools-Objective (PART-O) in a Norwegian context. METHODS: One hundred and twenty persons with TBI with verified intracranial lesions and persistent symptoms lasting more than 2 years, included in a randomized controlled trial, rated their participation using the PART-O at baseline. The PART-O with its three subscales (Productivity, Out and About, and Social Relations) was translated to Norwegian. Descriptive statistics, Cronbach's alpha, Rasch analysis, and correlation analysis were applied. RESULTS: The Rasch analysis indicated a unidimensional construct of PART-O and its subscales (χ2 < 12.69, p > 0.28). The internal consistency was moderate (Cronbach's alpha 0.48-0.52) and there was a need to reduce scaling options for most of the items. The Out and About and Productivity subscales had considerable floor effects. PART-O showed moderate positive correlation to TBI-related quality of life and global functioning. CONCLUSIONS: PART-O and its subscales reflect unidimensional aspects of participation. In the present Norwegian TBI population the original scaling of PART-O was too detailed for all subscales. The floor effects and suboptimal targeting between items and subjects participation level of the Out and About subscale is a matter of concern.
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Lesiones Traumáticas del Encéfalo , Calidad de Vida , Humanos , Encuestas y Cuestionarios , Psicometría , Noruega , Reproducibilidad de los ResultadosRESUMEN
Apicomplexans are a protozoan phylum of obligate parasites which may be highly virulent during acute infections, but may also persist as chronic infections which appear to have little fitness cost. Babesia microti is an apicomplexan haemoparasite that, in immunocompromised individuals, can cause severe, potentially fatal disease. However, in its natural host, wild field voles (Microtus agrestis), it exhibits chronic infections that have no detectable impact on survival or female fecundity. How is damage minimized, and what is the impact on the host's immune state and health? We examine the differences in immune state (here represented by expression of immune-related genes in multiple tissues) associated with several common chronic infections in a population of wild field voles. While some infections show little impact on immune state, we find strong associations between immune state and B. microti. These include indications of clearance of infected erythrocytes (increased macrophage activity in the spleen) and activity likely associated with minimizing damage from the infection (anti-inflammatory and antioxidant activity in the blood). By analysing gene expression from the same individuals at multiple time points, we show that the observed changes are a response to infection, rather than a risk factor. Our results point towards continual investment to minimize the damage caused by the infection. Thus, we shed light on how wild animals can tolerate some chronic infections, but emphasize that this tolerance does not come without a cost.
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Babesiosis , Animales , Femenino , Babesiosis/epidemiología , Babesiosis/parasitología , Roedores , Infección Persistente , Arvicolinae , InmunomodulaciónRESUMEN
Individuals differ in the nature of the immune responses they produce, affecting disease susceptibility and ultimately health and fitness. These differences have been hypothesized to have an origin in events experienced early in life that then affect trajectories of immune development and responsiveness. Here, we investigate how early-life immune expression profiles influence life history outcomes in a natural population of field voles, Microtus agrestis, in which we are able to monitor variation between and within individuals through time by repeat sampling of individually marked animals. We analysed the co-expression of 20 immune genes in early life to create a correlation network consisting of three main clusters, one of which (containing Gata3, Il10 and Il17) was associated with later-life reproductive success and susceptibility to chronic bacterial (Bartonella) infection. More detailed analyses supported associations between early-life expression of Il17 and reproductive success later in life, and of Il10 expression early in life and later infection with Bartonella. We also found significant association between an Il17 genotype and the early-life expression of Il10. Our results demonstrate that immune expression profiles can be manifested during early life with effects that persist through adulthood and that shape the variability among individuals in susceptibility to infection and fitness widely seen in natural populations.
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Infecciones por Bartonella , Bartonella , Enfermedades de los Roedores , Animales , Interleucina-10/genética , Roedores , Genotipo , Arvicolinae/genética , Enfermedades de los Roedores/microbiologíaRESUMEN
Severe skin pain when exposed to long wave ultraviolet radiation or visible light is the main symptom of erythropoietic protoporphyria (EPP). Treatment options for EPP are inadequate and new treatments are needed but hampered by the lack of valid efficacy outcomes. Phototesting with well-defined illumination of the skin can be performed reliably. We aimed to provide an overview of phototest procedures used to evaluate EPP treatments. Systematic searches of Embase, MEDLINE and the Cochrane Library were performed. Searches identified 11 studies using photosensitivity as efficacy outcome. The studies used eight different phototest protocols. Illuminations were performed with a filtered high-pressure mercury arc, or a xenon arc lamp equipped with monochromator or filters. Some used broadband, others narrowband illumination. In all protocols phototests were performed on the hands or the back. Endpoints were minimal dose required to induce either first symptom of discomfort, erythema, urticaria or intolerable pain. Other endpoints were change in erythema intensity or diameter of any type of flare after exposure compared to before. In conclusion, protocols displayed extensive variability in illumination set-up and evaluation of phototest reactions. Implementation of a standardized phototest method will allow more consistent and reliable outcome evaluation in future therapeutic research of protoporphyric photosensitivity.
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Trastornos por Fotosensibilidad , Protoporfiria Eritropoyética , Humanos , Protoporfiria Eritropoyética/terapia , Rayos Ultravioleta , Piel , EritemaRESUMEN
BACKGROUND: Vascular calcification is a known risk factor for cardiovascular events and mortality in patients with chronic kidney disease (CKD). However, since there is a lack of studies examining several arterial regions at a time, we aimed to evaluate the risk of major adverse cardiovascular events (MACE) and all-cause mortality according to calcium scores in five major arterial sites. METHODS: This was a prospective study of 580 patients from the Copenhagen CKD Cohort. Multidetector computed tomography of the coronary and carotid arteries, the thoracic aorta, the abdominal aorta and the iliac arteries was used to determine vascular calcification at baseline. Calcium scores were divided into categories: 0, 1-100, 101-400 and >400. RESULTS: During the follow-up period of 4.1 years a total of 59 cardiovascular events and 64 all-cause deaths occurred. In Cox proportional hazards models adjusted for age, sex, estimated glomerular filtration rate, hypertension, diabetes mellitus, hypercholesterolemia and smoking, only the coronary and carotid arteries, and the thoracic aorta were independent predictors of the designated endpoints. When examining the potential of calcification in the five arterial sites for predicting MACE, the difference in C-statistic was also most pronounced in these three sites, at 0.21 [95% confidence interval (CI) 0.16%-0.26%, P < .001], 0.26 (95% CI 0.22%-0.3%, P < .001) and 0.20 (95% CI 0.16%-0.24%, P < .001), respectively. This trend also applied to all-cause mortality. CONCLUSIONS: The overall results, including data on specificity, suggest that calcium scores of the coronary and carotid arteries have the most potential for identifying patients with CKD at high cardiovascular risk and for evaluating new therapies.
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Enfermedades Cardiovasculares , Enfermedad de la Arteria Coronaria , Insuficiencia Renal Crónica , Calcificación Vascular , Humanos , Estudios Prospectivos , Calcio , Vasos Coronarios , Insuficiencia Renal Crónica/terapia , Calcificación Vascular/diagnóstico por imagen , Calcificación Vascular/etiología , Factores de Riesgo , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/complicaciones , Enfermedad de la Arteria Coronaria/etiología , Enfermedad de la Arteria Coronaria/complicacionesRESUMEN
AIM: Liraglutide treatment is associated with gallbladder-related disorders and has been shown to delay postprandial gallbladder refilling. The gut hormones cholecystokinin (CCK), fibroblast growth factor 19 (FGF19) and glucagon-like peptide 2 (GLP-2), are known to regulate gallbladder motility and may be implicated in gallbladder-related disorders associated with liraglutide treatment. MATERIALS AND METHODS: In a double-blind, 12-week trial, 52 participants [50% male, age 47.6 ± 10.0 years, body mass index 32.6 ± 3.4 kg/m2 (mean ± standard deviation)] with obesity were randomized 1:1 to once-daily subcutaneous liraglutide (escalated from 0.6 mg to 3.0 mg once-daily) or placebo. During liquid meal tests performed at baseline, after the first dose and following 12 weeks of treatment, we evaluated postprandial gallbladder dynamics and plasma responses of CCK, FGF19 and GLP-2. RESULTS: Liraglutide reduced postprandial FGF19 after the first dose [area under the curve (AUC)0-240 min 24.8 vs. 48.0 min × ng/ml, treatment ratio (TR) (95% confidence interval) 0.52 (0.39; 0.69)] and following 12 weeks of treatment [AUC0-240 min 33.7 vs. 48.5 ng/ml × min, TR 0.69 (0.52; 0.93)]. Liraglutide also reduced postprandial GLP-2 responses (AUC0-240 min 3650 vs. 4894 min × pmol/L, TR 0.75 (0.62; 0.90)] following the first dose as well as after 12 weeks [AUC0-240 min 3760 vs. 4882 min × pmol/L, TR 0.77 (0.60; 0.99)]. Liraglutide increased postprandial responses of CCK after the first dose [AUC0-240 min 762 vs. 670 min × pmol/L; TR 1.14 (0.97; 1.33)] and following 12 weeks of treatment [AUC0-240 min 873 vs. 628 min × pmol/L; TR 1.39 (1.12; 1.73)]. CONCLUSION: Compared with placebo, treatment with liraglutide decreased postprandial FGF19 and GLP-2 concentrations and increased postprandial CCK concentrations, which may explain the delayed postprandial gallbladder refilling observed in individuals with obesity treated with liraglutide.
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Diabetes Mellitus Tipo 2 , Liraglutida , Humanos , Masculino , Adulto , Persona de Mediana Edad , Femenino , Liraglutida/farmacología , Liraglutida/uso terapéutico , Vesícula Biliar/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Obesidad/complicaciones , Índice de Masa Corporal , Periodo Posprandial , Método Doble Ciego , Glucemia/metabolismoRESUMEN
BACKGROUND: Distinguishing cutaneous malignant melanoma (CMM) from nevi can be clinically challenging. Suspicious lesions are therefore excised, resulting in many benign lesions being removed surgically to find 1 CMM. It has been proposed to use tape strip derived ribonucleic acid (RNA) to distinguish CMM from nevi. OBJECTIVE: To develop this technique further and validate if RNA profiles can rule out CMM in clinically suspicious lesions with 100% sensitivity. METHODS: Before surgical excision, 200 lesions clinically assessed as CMM were tape stripped. Expression levels of 11 genes on the tapes were investigated by RNA measurement and used in a rule-out test. RESULTS: Histopathology showed that 73 CMMs and 127 non-CMMs were included. Our test correctly identified all CMMs (100% sensitivity) based on the expression levels of 2 oncogenes, PRAME and KIT, relative to a housekeeping gene. Patient age and sample storage time were also significant. Simultaneously, our test correctly excluded CMM in 32% of non-CMM lesions (32% specificity). LIMITATIONS: Our sample contained a very high proportion of CMMs, perhaps due to inclusion during COVID-19 shutdown. Validation in a separate trial must be performed. CONCLUSION: Our results demonstrate that the technique can reduce removal of benign lesions by one-third without overlooking any CMMs.
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COVID-19 , Melanoma , Nevo , Neoplasias Cutáneas , Humanos , ARN , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/cirugía , Melanoma/diagnóstico , Melanoma/genética , Melanoma/patología , Nevo/diagnóstico , Nevo/genética , Prueba de COVID-19 , Antígenos de Neoplasias , Melanoma Cutáneo MalignoRESUMEN
BACKGROUND: Cutaneous malignant melanoma (MM) is potentially aggressive, and numerous clinically suspicious pigmented skin lesions are excised, causing unnecessary mutilation for patients at high healthcare costs, but without histopathological evidence of MM. The high number of excisions may be lowered by using more accurate diagnostics. Tape stripping (TS) of clinically suspicious lesions is a non-invasive diagnostic test of MM that can potentially lower the number needed to biopsy/excise. MATERIALS AND METHODS: The aim is to determine the diagnostic accuracy of TS in detecting MM in clinically suspicious pigmented skin lesions. This systematic review following PRISMA guidelines searched PubMed, Web of Science, and Embase (September 2022) using melanoma combined with tape stripping, adhesive patch(es), pigmented lesion assay, or epidermal genetic information retrieval. RESULTS: Ten studies were included. Sensitivity ranged from 68.8% (95% confidence interval [CI] 51.5, 82.1) to 100% (95% CI 91.0, 100). Specificity ranged from 69.1% (95% CI 63.8, 74.0) to 100% (95% CI 78.5, 100). A pooled analysis of five studies testing the RNA markers LINC00518 and PRAME found a sensitivity of 86.9% (95% CI 81.7, 90.8) and a specificity of 82.4% (95% CI 80.8, 83.9). CONCLUSION: Overall quality of studies was low, and the reliability of sensitivity and specificity is questionable. However, TS may supplement well-established diagnostic methods as pooled analysis of five studies indicates a moderate sensitivity. Future studies are needed to obtain more reliable data as independent studies with no conflict of interest.
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Biopsia , Melanoma , Neoplasias Cutáneas , Cinta Quirúrgica , Humanos , Antígenos de Neoplasias/genética , Biopsia/métodos , Melanoma/patología , Melanoma/cirugía , Trastornos de la Pigmentación/patología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/cirugía , Melanoma Cutáneo MalignoRESUMEN
OBJECTIVE: Self-control is a meaningful predictor of crucial life outcomes. Knowingly, genes contribute substantially to differences in self-control, but behavioral genetic findings are often misinterpreted regarding environmental influences. Therefore, we reinvestigate the heritability of self-control as well as potential environmental influences, namely parenting and a chaotic home environment. METHOD: We used cross-sectional and longitudinal data from the German twin family study TwinLife (N = 3354 individuals), structured in a multicohort design in which 13-, 19-, and 25-year-old twins rated their self-control, parents' behavior, and home environment. RESULTS: Results showed increasing mean levels and 1-year stabilities for self-control accompanied by substantial genetic influences, increasing particularly from ages 19 to 25 (53% to 76%). While chaotic home environments and negative parenting were phenotypically associated with lower self-control, twin difference models revealed that differences in these individually perceived "environments" directly predicted self-control differences (ß = -0.16 to -0.28) within families when controlling for genetic and environmental similarities. CONCLUSIONS: In addition to the genetic anchoring of self-control, results indicate that environmental factors such as negative family environments are meaningful and depend on individual perceptions within families. Interventions for enhancing self-control should, therefore, rely on individual perspectives rather than objective characteristics of home environments.
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Responsabilidad Parental , Autocontrol , Adolescente , Adulto , Humanos , Adulto Joven , Estudios Transversales , Gemelos/genéticaRESUMEN
BACKGROUND: This is a qualitative feasibility study of the Child in Context Intervention (CICI). The CICI is an individualized, goal-oriented and home-based tele-rehabilitation intervention which targets everyday functioning of children (6-16 years) with acquired brain injury in the chronic stage, and their families, one year or more after insult, who have ongoing challenges (physical, cognitive, behavioral, social and/or psychological). The aim of this study is to better understand how children, parents and teachers experienced participation and acceptability; to develop knowledge about the mechanisms of change, and to explore how the CICI was tailored to the context. METHODS: Six families and schools participated in the intervention, which comprised seven tele-rehabilitation sessions in which the child and parent participated, one in-person parent seminar and four digital school meetings. A multidisciplinary team delivered the intervention to 23 participants over a 4- to 5-month period. The intervention involved psychoeducation about targeted acquired brain injury-related problems, such as fatigue, pain, or social challenges. All but one consented to participate in the current digital interview study. The data were analyzed using content analysis. RESULTS: The experience of participation and acceptability varied among the children. Attendance was consistently high; the child participants felt mostly listened to and could influence goal setting and strategies. However, engaging and motivating the child participants proved somewhat challenging. The parents found the CICI rewarding, useful and relevant. However, they had different experiences regarding which intervention component they perceived as most helpful. Some argued in favor of the 'whole intervention', while others highlighted new knowledge, SMART goals or the school collaboration. The teachers found the intervention acceptable and useful but wanted a better meeting plan. They had difficulties in finding time for meetings, emphasized the involvement of school leaders, and appreciated the digital format. CONCLUSIONS: Overall, the intervention was perceived as acceptable, and the participants felt that the various intervention components contributed to improvements. The CICI's flexibility facilitated tailoring to different contexts based on the children's functional level. The digital format saved time and provided flexibility regarding the amount of attendance but limited full participation from children with more severe cognitive impairments. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04186182.
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Telerrehabilitación , Niño , Humanos , Estudios de Factibilidad , Padres/psicología , Investigación Cualitativa , Instituciones Académicas , AdolescenteRESUMEN
OBJECTIVE: Hypertension contributes to increased risk of cardiovascular disease in patients with Turner syndrome (TS). Our objective was to evaluate blood pressure (BP) in girls with TS followed longitudinally through childhood and adolescence compared to a newly established BP reference material. DESIGN: Cohort study with data collected from 1991 to 2019 consisting of a population-based reference cohort and a group of girls with TS followed at a single tertiary centre. PATIENTS/PARTICIPANTS: Reference population of 1888 healthy girls with 4890 BP recordings and 60 girls with TS with 365 BP recordings. MEASUREMENTS: Difference in diastolic BP (DBP) and systolic BP (SBP), expressed in standard deviation scores (SDS), between girls with TS and the reference population, unadjusted and adjusted for BMI. Difference in BP (SDS) between TS subgroups (karyotype, oestrogen treatment, cardiac diagnosis). RESULTS: The girls with TS had significantly higher DBP (mean ± SD, 0.72 SDS ± 0.95; p < .001) and SBP (0.53 SDS ± 1.11; p = .001) than the reference population. Adjusted for BMI, girls with TS had significantly higher DBP (mean ± SE, 0.71 SDS ± 0.12; p < .001) but not SBP (0.17 SDS ± 0.16; p = .29). There was no significant difference in DBP (median, IQR: 0.97 SDS, 0.30-1.58 vs. 0.76 SDS, 0.10-1.20; p = .31) or SBP (0.51 SDS, 0.15-1.30 vs. 0.57 SDS, -0.30 to 1.05; p = .67) between individuals with or without a cardiac diagnosis. In the TS population, 55% (31/56) had at least one BP recording above the hypertension threshold. CONCLUSIONS: Our findings indicate that standardised longitudinal routine monitoring of BP in girls with TS already in childhood is of utmost importance.
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Hipertensión , Síndrome de Turner , Adolescente , Presión Sanguínea , Estudios de Cohortes , Dinamarca , Femenino , Humanos , Hipertensión/diagnóstico , MasculinoRESUMEN
BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease and represents a wide spectrum ranging from mild steatosis to non-alcoholic steatohepatitis with or without fibrosis to overt cirrhosis. Patients with NAFLD have a high risk of developing cardiovascular disease and chronic kidney disease (CKD). So far there has been scarce evidence of the prevalence of NAFLD among patients with CKD. We investigated the prevalence of moderate-severe hepatic steatosis graded according to the definition of NAFLD in a cohort of patients with CKD. METHODS: Hepatic liver fat content was evaluated by computed tomography (CT) scan in 291 patients from the Copenhagen CKD Cohort Study and in 866 age- and sex-matched individuals with normal kidney function from the Copenhagen General Population Study. Liver attenuation density <48 HU was used as a cut-off value for moderate-severe hepatic steatosis. RESULTS: The prevalence of moderate-severe hepatic steatosis was 7.9 and 10.7% (P = 0.177) among patients with CKD and controls, respectively. No association between liver fat content and CKD stage was found. In the pooled dataset from both cohorts, adjusted odds ratios for moderate-severe hepatic steatosis among persons with diabetes, overweight and obesity were 3.1 [95% confidence interval (CI) 1.6-5.9], 14.8 (95% CI 4.6-47.9) and 42.0 (95% CI 12.9-136.6), respectively. CONCLUSIONS: In a cohort of 291 patients with CKD, kidney function was not associated with the prevalence of moderate-severe hepatic steatosis as assessed by CT scan.
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Enfermedad del Hígado Graso no Alcohólico , Insuficiencia Renal Crónica , Estudios de Cohortes , Estudios Transversales , Humanos , Hígado , Cirrosis Hepática/complicaciones , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Prevalencia , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/epidemiologíaRESUMEN
The metallobiochemistry underlying the formation of the inorganic N-N-bond-containing molecules nitrous oxide (N2O), dinitrogen (N2), and hydrazine (N2H4) is essential to the lifestyles of diverse organisms. Similar reactions hold promise as means to use N-based fuels as alternative carbon-free energy sources. This review discusses research efforts to understand the mechanisms underlying biological N-N bond formation in primary metabolism and how the associated reactions are tied to energy transduction and organismal survival. These efforts comprise studies of both natural and engineered metalloenzymes as well as synthetic model complexes.
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Metaloproteínas/metabolismo , Nitrógeno/metabolismo , Hidrazinas/química , Hidrazinas/metabolismo , Metaloproteínas/química , Modelos Moleculares , Nitrógeno/química , Óxido Nitroso/química , Óxido Nitroso/metabolismoRESUMEN
CONTEXT AND PURPOSE: There is an urgent need to develop vitamin D dietary recommendations for dark-skinned populations resident at high latitude. Using data from randomised controlled trials (RCTs) with vitamin D3-supplements/fortified foods, we undertook an individual participant data-level meta-regression (IPD) analysis of the response of wintertime serum 25-hydroxyvitamin (25(OH)D) to total vitamin D intake among dark-skinned children and adults residing at ≥ 40° N and derived dietary requirement values for vitamin D. METHODS: IPD analysis using data from 677 dark-skinned participants (of Black or South Asian descent; ages 5-86 years) in 10 RCTs with vitamin D supplements/fortified foods identified via a systematic review and predefined eligibility criteria. Outcome measures were vitamin D intake estimates across a range of 25(OH)D thresholds. RESULTS: To maintain serum 25(OH)D concentrations ≥ 25 and 30 nmol/L in 97.5% of individuals, 23.9 and 27.3 µg/day of vitamin D, respectively, were required among South Asian and 24.1 and 33.2 µg/day, respectively, among Black participants. Overall, our age-stratified intake estimates did not exceed age-specific Tolerable Upper Intake Levels for vitamin D. The vitamin D intake required by dark-skinned individuals to maintain 97.5% of winter 25(OH)D concentrations ≥ 50 nmol/L was 66.8 µg/day. This intake predicted that the upper 2.5% of individuals could potentially achieve serum 25(OH)D concentrations ≥ 158 nmol/L, which has been linked to potential adverse effects in older adults in supplementation studies. CONCLUSIONS: Our IPD-derived vitamin D intakes required to maintain 97.5% of winter 25(OH)D concentrations ≥ 25, 30 and 50 nmol/L are substantially higher than the equivalent estimates for White individuals. These requirement estimates are also higher than those currently recommended internationally by several agencies, which are based predominantly on data from Whites and derived from standard meta-regression based on aggregate data. Much more work is needed in dark-skinned populations both in the dose-response relationship and risk characterisation for health outcomes. TRAIL REGISTRATION: PROSPERO International Prospective Register of Systematic Reviews (Registration Number: CRD42018097260).
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Deficiencia de Vitamina D , Vitamina D , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Suplementos Dietéticos , Humanos , Persona de Mediana Edad , Necesidades Nutricionales , Estaciones del Año , Deficiencia de Vitamina D/epidemiología , Deficiencia de Vitamina D/prevención & control , Vitaminas , Adulto JovenRESUMEN
Treelines are expected to expand into alpine ecosystems with global warming, but herbivory may delay this expansion. This study quantifies long-term effects of temporally varying sheep densities on birch recruitment and growth in the treeline ecotone. We examined treeline ecotone successional trajectories and legacy effects in a replicated experimental setup, where enclosures were present for 14 years with three different sheep densities (0, 25, 80 sheep km-2). Before and after the enclosures were present, the site had an ambient sheep density of 20-25 km-2. We sampled field data 4 years after enclosure removal and compared these to data sampled 8 and 9 years after enclosure erection. We sampled data on birch browsing pressure, birch distribution across life-stages (recruits, saplings, and mature trees), and birch annual radial growth. Fourteen years of increased or decreased sheep density had observable legacy effects depending on birch life-stage. Birch recruit prevalence decreased in areas, where sheep were reintroduced after being absent for 14 years. For the same areas, sapling and mature tree prevalence increased, indicating that these areas have entered alternative successional trajectories compared to areas, where sheep were present the whole time. Birch annual radial growth showed a lag effect of 2 years after enclosure removal, with growth decreasing in areas where sheep had been absent for 14 years and increasing where sheep densities were high. Thus, decadal-scale absences of herbivores can leave legacy effects due to increased numbers of trees that have high resistance to later-introduced herbivore browsing.
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Ecosistema , Herbivoria , Animales , Betula , Calentamiento Global , Ovinos , ÁrbolesRESUMEN
AIMS: The purpose of the work was to investigate bacterial levels and diversity as well as survival of Salmonella in used dish washing sponges and brushes and identify consumer practices that can potentially explain bacterial status of these items. METHODS AND RESULTS: Used washing up utensils were collected from consumers. The bacterial numbers (TVC) were very variable with an extremely high median level (10.3 log cfu/item) in Portuguese sponges and lower levels in Norwegian items (7.3 and 7.0 cfu/item for sponges and brushes). No self-reported practices or household composition could explain differences found in TVC levels among the collected sponges. Lower mean TVC levels were found in unworn brushes and brushes regularly cleaned with soap, but the differences were modest (1.5 log or less). A common set of bacteria was found in brushes and sponges, dominated by Acinetobacter, Chryseobacterium, Enhydrobacter, Enterobacteriaceae and Pseudomonas. There was no difference in TVC or bacterial diversity between conventional and antimicrobial sponges containing silver after 4 weeks of use. For used brushes inoculated with Salmonella and allowed to dry overnight, a significant reduction in Salmonella numbers was observed. No reduction was observed for brushes stored in humid conditions (in a plastic bag) or for sponges regardless of storing conditions. CONCLUSIONS: Overall, lower bacterial levels were observed in used brushes than in sponges, and Salmonella died more rapidly in brushes. A common set of non-pathogenic bacteria dominated in brushes and sponges. SIGNIFICANCE AND IMPACT OF STUDY: The study demonstrates that the use of brushes may be more hygienic than the use of sponges.
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Bacterias , Salmonella , Enterobacteriaceae , HigieneRESUMEN
BACKGROUND: Constipation is a prevalent gastrointestinal complication in diabetes. The pathophysiology may include neural dysfunction and impaired gastrocolic reflex; however, investigation of the latter has been limited in diabetes. Using the wireless motility capsule, we investigated whether the gastrocolic reflex was impaired in adults with type 1 diabetes compared to healthy. METHODS: One hundred and four adults with type 1 diabetes underwent investigation with the wireless motility capsule and recorded sleep cycle, eating habits, and bowel movements in a diary. Colonic motility index, contraction amplitudes, time-to-peak, peak motility, and colonic transit time were investigated directly in response to a meal. Diagnosis of peripheral (nerve conduction) and autonomic (orthostatic hypotension) polyneuropathy was verified. RESULTS: In comparison with health, people with diabetes had at the time of ingestion decreased motility index and contraction amplitudes (p < 0.001), prolonged time-to-peak (p = 0.01), and borderline decreased peak motility (p = 0.06), which taken together indicate impaired coordination of the gastrocolic reflex. These features were most prominent in those with concomitant peripheral or autonomic neuropathy. Additionally, they were associated with prolonged colonic transit time (p > 0.01). CONCLUSIONS: In type 1 diabetes, the gastrocolic reflex was delayed and diminished and further associated with the presence of neuropathy and constipation. These results suggest that impaired reflex is part of the underlying pathogenesis in the development of constipation.
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Diabetes Mellitus Tipo 1 , Tránsito Gastrointestinal , Adulto , Colon , Estreñimiento/etiología , Diabetes Mellitus Tipo 1/complicaciones , Motilidad Gastrointestinal/fisiología , Tránsito Gastrointestinal/fisiología , Humanos , ReflejoRESUMEN
OBJECTIVES: Comprehensive review of existing types and effectiveness of community-based interventions delivered to adults (mean age 18-65 years) with long-lasting (≥6 months) difficulties following acquired brain injury (ABI). DESIGN: Systematic review of controlled intervention studies published until February 2021. MAIN MEASURES: Systematic searches in databases (MEDLINE, PsycINFO, Database of Abstracts of Reviews of Effects [Cochrane Library], and Cochrane Central Register of Controlled Trials [Cochrane Library]) and inclusion of English peer-reviewed full-text articles; randomized or controlled community-based intervention studies; sample size of 20 or more participants; and 3 or more intervention sessions. Two reviewers independently extracted data for the synthesis and assessed the methodological quality. Data extraction included study characteristics, demographics of participants, content and dose of intervention, outcome measures, and findings. RESULT: The search returned 7386 publications, of which 49 eligible studies were included, revealing a diverse range of community-based interventions and a myriad of outcome measures applied for assessing functional capacities, participation, and quality of life in the chronic phase of ABI. Intervention types encompassed 14 holistic, 23 physical, and 12 specific interventions. A large heterogeneity regarding intervention frequency and intensity was found. Meta-analyses performed on the holistic, physical, and specific interventions did not indicate any significant pooled effects but showed highly variable effects between individuals, both in persons with traumatic and nontraumatic brain injuries. CONCLUSIONS: Because of lack of pooled effects within types of community-based interventions, specific evidence-based recommendations within holistic, physical, and specific interventions designed to mitigate long-lasting ABI problems cannot be made. This review highlights the need for future studies to address methodological issues concerning larger sample size, lack of clear description interventions and comparator, missing reports of effects in change scores, need for consistent use of recommended outcome measures, and investigating the wide variety in intervention responsiveness among participants with ABI. Systematic review registration: PROSPERO (CRD42019124949).