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1.
J Clin Immunol ; 44(3): 66, 2024 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-38363477

RESUMEN

B cells and their secreted antibodies are fundamental for host-defense against pathogens. The generation of high-affinity class switched antibodies results from both somatic hypermutation (SHM) of the immunoglobulin (Ig) variable region genes of the B-cell receptor and class switch recombination (CSR) which alters the Ig heavy chain constant region. Both of these processes are initiated by the enzyme activation-induced cytidine deaminase (AID), encoded by AICDA. Deleterious variants in AICDA are causal of hyper-IgM syndrome type 2 (HIGM2), a B-cell intrinsic primary immunodeficiency characterised by recurrent infections and low serum IgG and IgA levels. Biallelic variants affecting exons 2, 3 or 4 of AICDA have been identified that impair both CSR and SHM in patients with autosomal recessive HIGM2. Interestingly, B cells from patients with autosomal dominant HIGM2, caused by heterozygous variants (V186X, R190X) located in AICDA exon 5 encoding the nuclear export signal (NES) domain, show abolished CSR but variable SHM. We herein report the immunological and functional phenotype of two related patients presenting with common variable immunodeficiency who were found to have a novel heterozygous variant in AICDA (L189X). This variant led to a truncated AID protein lacking the last 10 amino acids of the NES at the C-terminal domain. Interestingly, patients' B cells carrying the L189X variant exhibited not only greatly impaired CSR but also SHM in vivo, as well as CSR and production of IgG and IgA in vitro. Our findings demonstrate that the NES domain of AID can be essential for SHM, as well as for CSR, thereby refining the correlation between AICDA genotype and SHM phenotype as well as broadening our understanding of the pathophysiology of HIGM disorders.


Asunto(s)
Citidina Desaminasa , Síndrome de Inmunodeficiencia con Hiper-IgM , Cambio de Clase de Inmunoglobulina , Humanos , Citidina Desaminasa/genética , Citidina Desaminasa/metabolismo , Síndrome de Inmunodeficiencia con Hiper-IgM/genética , Inmunoglobulina A/genética , Cambio de Clase de Inmunoglobulina/genética , Inmunoglobulina G/genética , Fenotipo , Hipermutación Somática de Inmunoglobulina
2.
Appl Environ Microbiol ; 90(5): e0169423, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38624219

RESUMEN

Given the multitude of extracellular enzymes at their disposal, many of which are designed to degrade nature's polymers (lignin, cutin, cellulose, etc.), fungi are adept at targeting synthetic polyesters with similar chemical composition. Microbial-influenced deterioration of xenobiotic polymeric surfaces is an area of interest for material scientists as these are important for the conservation of the underlying structural materials. Here, we describe the isolation and characterization of the Papiliotrema laurentii 5307AH (P. laurentii) cutinase, Plcut1. P. laurentii is basidiomycete yeast with the ability to disperse Impranil-DLN (Impranil), a colloidal polyester polyurethane, in agar plates. To test whether the fungal factor involved in this clearing was a secreted enzyme, we screened the ability of P. laurentii culture supernatants to disperse Impranil. Using size exclusion chromatography (SEC), we isolated fractions that contained Impranil-clearing activity. These fractions harbored a single ~22 kD band, which was excised and subjected to peptide sequencing. Homology searches using the peptide sequences identified, revealed that the protein Papla1 543643 (Plcut1) displays similarities to serine esterase and cutinase family of proteins. Biochemical assays using recombinant Plcut1 confirmed that this enzyme has the capability to hydrolyze Impranil, soluble esterase substrates, and apple cutin. Finally, we confirmed the presence of the Plcut1 in culture supernatants using a custom antibody that specifically recognizes this protein. The work shown here supports a major role for the Plcut1 in the fungal degradation of natural polyesters and xenobiotic polymer surfaces.IMPORTANCEFungi play a vital role in the execution of a broad range of biological processes that drive ecosystem function through production of a diverse arsenal of enzymes. However, the universal reactivity of these enzymes is a current problem for the built environment and the undesired degradation of polymeric materials in protective coatings. Here, we report the identification and characterization of a hydrolase from Papiliotrema laurentii 5307AH, an aircraft-derived fungal isolate found colonizing a biodeteriorated polymer-coated surface. We show that P. laurentii secretes a cutinase capable of hydrolyzing soluble esters as well as ester-based compounds forming solid surface coatings. These findings indicate that this fungus plays a significant role in biodeterioration through the production of a cutinase adept at degrading ester-based polymers, some of which form the backbone of protective surface coatings. The work shown here provides insights into the mechanisms employed by fungi to degrade xenobiotic polymers.


Asunto(s)
Hidrolasas de Éster Carboxílico , Proteínas Fúngicas , Poliésteres , Proteínas Recombinantes , Hidrolasas de Éster Carboxílico/metabolismo , Hidrolasas de Éster Carboxílico/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Poliésteres/metabolismo , Hidrólisis
3.
PLoS Comput Biol ; 18(11): e1010708, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36441766

RESUMEN

The clustering of platelet glycoprotein receptors with cytosolic YxxL and YxxM motifs, including GPVI, CLEC-2 and PEAR1, triggers activation via phosphorylation of the conserved tyrosine residues and recruitment of the tandem SH2 (Src homology 2) domain effector proteins, Syk and PI 3-kinase. We have modelled the clustering of these receptors with monovalent, divalent and tetravalent soluble ligands and with transmembrane ligands based on the law of mass action using ordinary differential equations and agent-based modelling. The models were experimentally evaluated in platelets and transfected cell lines using monovalent and multivalent ligands, including novel nanobody-based divalent and tetravalent ligands, by fluorescence correlation spectroscopy. Ligand valency, receptor number, receptor dimerisation, receptor phosphorylation and a cytosolic tandem SH2 domain protein act in synergy to drive receptor clustering. Threshold concentrations of a CLEC-2-blocking antibody and Syk inhibitor act in synergy to block platelet aggregation. This offers a strategy for countering the effect of avidity of multivalent ligands and in limiting off-target effects.


Asunto(s)
Glicoproteínas de Membrana Plaquetaria , Dominios Homologos src , Simulación por Computador
4.
Intern Med J ; 53(2): 280-284, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36822603

RESUMEN

Kidney donor allocation can occasionally be difficult in Australia given a small population spread over vast distances. Therefore, between 2017 and 2019 our service allowed transplantation from deceased donors into local (same-state) preemptive recipients, only if no well-matched dialysis-dependent transplant waitlist recipient was available. Transplantation using this novel allocation pathway was associated with good clinical and immunological outcomes.


Asunto(s)
Trasplante de Riñón , Humanos , Australia Occidental , Donantes de Tejidos , Diálisis Renal , Riñón , Supervivencia de Injerto
5.
Biochem Soc Trans ; 50(5): 1329-1339, 2022 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-36111814

RESUMEN

Understanding the basis of the immune determinants controlling disease outcome is critical to provide better care to patients and could be exploited for therapeutics and vaccine design. The discovery of the human immunodeficiency virus (HIV) virus as the causing agent of acquired immunodeficiency syndrome (AIDS) decades ago, led to a tremendous amount of research. Among the findings, it was discovered that some rare HIV+ individuals, called HIV controllers (HICs), had the ability to control the virus and keep a low viral load without the need of treatment. This ability allows HICs to delay or avoid progression to AIDS. HIV control is strongly associated with the expression of human leukocyte antigen (HLA) alleles in HICs. From the HIV protective HLAs described, HLA-B57 is the most frequent in HIC patients. HLA-B57 can present a large range of highly conserved Gag-derived HIV peptides to CD8+ T cells and natural killer (NK) cells, both the focus of this review. So far there are limited differences in the immune response strength, magnitude, or receptor repertoire towards HIV epitopes that could explain viral control in HICs. Interestingly, some studies revealed that during early infection the large breadth of the immune response towards HIV mutants in HLA-B57+ HIC patients, might in turn influence the disease outcome.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Infecciones por VIH , VIH-1 , Humanos , Antígenos HLA-B/metabolismo , Linfocitos T CD8-positivos/metabolismo , Células Asesinas Naturales/metabolismo
6.
Clin Endocrinol (Oxf) ; 96(2): 165-174, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34668586

RESUMEN

OBJECTIVE: Being born small for gestational age (SGA) is frequently associated with unexplained disorders of sex development (nonspecific DSD) in boys. Little is known about their future growth, puberty and testicular function. Our objective is to determine the long-term endocrine outcome of boys born SGA who have a nonspecific DSD. DESIGN: Boys with a nonspecific DSD born SGA and appropriate for GA (AGA) were retrieved through the International Disorders of Sex Development registry and retrospective data collected, based on a spreadsheet containing 102 items. PATIENTS AND MEASUREMENTS: In total, 179 boys were included, of which 115 were born SGA and 64 were born AGA. Their growth and pubertal development were compared. Serum LH, FSH, testosterone, AMH and inhibin B levels in infancy and puberty were analysed to assess testicular function. RESULTS: At 2 years of age, 30% of SGA boys had incomplete or absent catch-up growth. Boys born SGA also had higher LH during minipuberty and lower testosterone in stimulation tests (p = 0.037 and 0.040, respectively), as compared to boys born AGA. No differences were observed in timing or course of puberty or end-pubertal hormone levels. CONCLUSIONS: Almost one out of three SGA boys with a nonspecific DSD experiences insufficient catch-up growth. In addition, our data suggest dysfunction of infantile Leydig cells or altered regulation of the hypothalamic-pituitary-gonadal axis in SGA boys during childhood. Sex steroid production during puberty seems unaffected.


Asunto(s)
Recién Nacido Pequeño para la Edad Gestacional , Pubertad , Edad Gestacional , Humanos , Recién Nacido , Masculino , Estudios Retrospectivos , Testosterona
7.
Mov Disord ; 37(8): 1683-1692, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35702056

RESUMEN

BACKGROUND: Dystonia is an understudied motor feature of Parkinson's disease (PD). Although considerable efforts have focused on brain oscillations related to the cardinal symptoms of PD, whether dystonia is associated with specific electrophysiological features is unclear. OBJECTIVE: The objective of this study was to investigate subcortical and cortical field potentials at rest and during contralateral hand and foot movements in patients with PD with and without dystonia. METHODS: We examined the prevalence and distribution of dystonia in patients with PD undergoing deep brain stimulation surgery.  During surgery, we recorded intracranial electrophysiology from the motor cortex and directional electrodes in the subthalamic nucleus (STN) both at rest and during self-paced repetitive contralateral hand and foot movements. Wavelet transforms and mixed models characterized changes in spectral content in patients with and without dystonia. RESULTS: Dystonia was highly prevalent at enrollment (61%) and occurred most commonly in the foot. Regardless of dystonia status, cortical recordings display beta (13-30 Hz) desynchronization during movements versus rest, while STN signals show increased power in low frequencies (6.0 ± 3.3 and 4.2 ± 2.9 Hz peak frequencies for hand and foot movements, respectively). Patients with PD with dystonia during deep brain stimulation surgery displayed greater M1 beta power at rest and STN low-frequency power during movements versus those without dystonia. CONCLUSIONS: Spectral power in motor cortex and STN field potentials differs markedly during repetitive limb movements, with cortical beta desynchronization and subcortical low-frequency synchronization, especially in patients with PD with dystonia. Greater knowledge on field potential dynamics in human motor circuits can inform dystonia pathophysiology in PD and guide novel approaches to therapy. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Estimulación Encefálica Profunda , Distonía , Trastornos Distónicos , Enfermedad de Parkinson , Núcleo Subtalámico , Distonía/etiología , Humanos , Núcleo Subtalámico/fisiología
8.
J Headache Pain ; 23(1): 63, 2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-35668368

RESUMEN

BACKGROUND: Initial evidence have shown the short-term efficacy of sTMS in the acute and preventive treatment of migraine. It is unknown whether this treatment approach in the long-term is effective and well tolerated in difficult-to-treat migraine. METHODS: This is a prospective, single centre, open-label, real-world analysis conducted in difficult-to-treat patients with high-frequency episodic migraine (HFEM) and chronic migraine (CM) with and without medication overuse headache (MOH), who were exposed to sTMS therapy. Patients responding to a three-month sTMS treatment, continued the treatment and were assessed again at month 12. The cut-off outcome for treatment continuation was reduction in the monthly moderate to severe headache days (MHD) of at least 30% (headache frequency responders) and/or a ≥ 4-point reduction in headache disability using the Headache Impact test-6 (HIT-6) (headache disability responders). RESULTS: One hundred fifty-three patients were included in the analysis (F:M = 126:27, median age 43, IQR 32.3-56.8). At month 3, 93 out of 153 patients (60%) were responders to treatment. Compared to baseline, the median reduction in monthly headache days (MHD) for all patients at month 3 was 5.0 days, from 18.0 (IQR: 12.0-26.0) to 13.0 days (IQR: 5.75-24.0) (P = 0.002, r = - 0.29) and the median reduction in monthly migraine days (MMD) was 4.0 days, from 13.0 (IQR: 8.75-22.0) to 9.0 (IQR: 4.0-15.25) (P = 0.002, r = - 0.29). Sixty-nine out of 153 patients (45%) reported a sustained response to sTMS treatment at month 12. The percentage of patients with MOH was reduced from 52% (N = 79/153) at baseline to 19% (N = 29/153) at month 3, to 8% (N = 7/87) at month 12. There was an overall median 4-point reduction in HIT-6 score, from 66 (IQR: 64-69) at baseline to 62 at month 3 (IQR: 56-65) (P < 0.001, r = - 0.51). A total of 35 mild/moderate adverse events were reported by 23 patients (15%). One patient stopped sTMS treatment due to scalp sensitivity. CONCLUSIONS: This open label analysis suggests that sTMS may be an effective, well-tolerated treatment option for the long-term prevention of difficult-to-treat CM and HFEM.


Asunto(s)
Cefaleas Secundarias , Trastornos Migrañosos , Adulto , Cefalea/etiología , Cefaleas Secundarias/etiología , Humanos , Trastornos Migrañosos/tratamiento farmacológico , Trastornos Migrañosos/prevención & control , Estudios Prospectivos , Estimulación Magnética Transcraneal , Resultado del Tratamiento
9.
Ecol Food Nutr ; 61(1): 1-19, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33908326

RESUMEN

Despite Rwanda's impressive economic success over the last decade, household food insecurity persists, particularly in rural areas. Empirical evidence is therefore deemed necessary to inform policies addressing food insecurity, hunger and poverty in general. This study examines household food security and its determinants in the rural areas of Southern and Northern provinces of Rwanda. Using cross-sectional data collected from 534 farming households, we estimated household food security status by Food Consumption Score (FCS) and Food Insecurity Experience Scale (FIES) and applied ordered Probit model to identify drivers of household food security. The results indicate that a significant proportion (74.4%) of households had an acceptable FCS, but 36.52% of the farming households experienced moderate and severe food insecurity when assessed with FIES. Ownership of livestock was identified as a key determinant of food security using both metrics, which affirms the importance of combating hunger and food insecurity in Rwanda through their 'one cow per household policy' and recommends that this policy be strengthened.


Asunto(s)
Composición Familiar , Abastecimiento de Alimentos , Agricultura , Estudios Transversales , Seguridad Alimentaria , Humanos , Rwanda
10.
J Urol ; 206(3): 734-744, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33955779

RESUMEN

PURPOSE: We assessed the long-term surgical, functional urinary and sexual outcomes of adolescent and young adult men who underwent childhood hypospadias repair. MATERIALS AND METHODS: Men born with nonsyndromic hypospadias and healthy male controls aged 16-21 years old were recruited, and their surgical, urinary, sexual functional and aesthetic outcomes assessed. Good outcome was defined as a patent and orthotopic meatus without fistulas, and straight erections (<30 degree curvature) without erectile or ejaculatory problems. Statistics included regression analyses, chi-square/Fisher exact tests and Student's t/Mann-Whitney U and Kruskal-Wallis tests. RESULTS: A total of 193 patients and 50 controls participated 16.4 years (range 8.2-21.2) after initial repair. At least 1 reintervention was performed in 39.2%. The highest reintervention rate was found in those younger than 12 months at initial repair, even when excluding proximal hypospadias cases. A disturbed urinary and/or suboptimal sexual functional outcome was seen in 52.9% of cases. Suboptimal voiding was found in 22.1%, although few had relevant residual urine. More reinterventions and proximal hypospadias cases were associated with suboptimal urinary outcome, and the latter also with impaired sexual function. Poor inter-observer agreements were found between physician and patient genital appraisal. CONCLUSIONS: In 52.9% of cases, at least 1 concern was identified that required long-term followup. Hypospadias repair below 12 months was associated with more reinterventions. Adopting a restrictive attitude toward aesthetic refinement, unless on the patient's own request, could improve urinary outcomes.


Asunto(s)
Hipospadias/cirugía , Complicaciones Posoperatorias/epidemiología , Disfunciones Sexuales Fisiológicas/epidemiología , Trastornos Urinarios/epidemiología , Procedimientos Quirúrgicos Urológicos Masculinos/efectos adversos , Adolescente , Factores de Edad , Estudios de Casos y Controles , Niño , Estética , Estudios de Seguimiento , Voluntarios Sanos , Humanos , Hipospadias/complicaciones , Masculino , Satisfacción del Paciente , Complicaciones Posoperatorias/etiología , Reoperación/efectos adversos , Reoperación/estadística & datos numéricos , Disfunciones Sexuales Fisiológicas/etiología , Encuestas y Cuestionarios , Tiempo de Tratamiento/estadística & datos numéricos , Resultado del Tratamiento , Trastornos Urinarios/etiología , Procedimientos Quirúrgicos Urológicos Masculinos/estadística & datos numéricos , Adulto Joven
11.
World J Urol ; 39(4): 1013-1019, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32067073

RESUMEN

PURPOSE: To review existing literature about fertility and sexuality of boys born with complex congenital genitourinary anomalies. METHODS: A Pubmed review was performed in December 2018 to identify the most relevant original manuscripts regarding male complex congenital conditions affecting the urogenital system in male patients including spina bifida (SB), bladder exstrophy-epispadias complex (BEEC) and hypospadias. A comprehensive review was drafted exploring sexual dysfunction from a medical, psychosexual, surgical and reproductive point of view during transition from childhood (or adolescence) to adulthood. RESULTS: About 75% of men with SB have erectile dysfunction (ED) (Gamé et al. in Urology 67(3):566-570, 2006; Diamond et al. in 58(4):434-435, 1986). Most SB patients have impaired sexual development mainly due to diminished self-esteem, dependence on caregivers and lack of privacy (Blum et al. in Pediatrics 88(2):280-285, 1991). Men with BEEC have fewer intimate relationships than women because of the greater difficulties with issues regarding their genitalia and sexual activities (Deans et al. in Am J Obstet Gynecol 206(6):496.e1-496.e6, 2012). However, a good quality of life is achievable with the effective use of coping strategies (Deng et al. in Transl Androl Urol 7:941, 2018; Rikken et al. in BMC Womens Health 18(1):163, 2018; Friedler et al. in Reprod Biomed Online 32(1):54-61, 2016). Chordee occurs in 25% of all hypospadias patients. More severe hypospadias is related to a greater risk for complications. The long-term sexual quality of life (QoL) in men who underwent hypospadias surgery is influenced by a lot of factors. Therefore, an interactive and dynamic biopsychosocial model of sexual QoL was proposed. CONCLUSIONS: The care of patients with congenital urologic conditions becomes a challenge especially in the period of 'transition'. The goal of follow-up is a holistic management viewed from a medical, psychosexual, surgical end reproductive point. All patients should be asked for specific urinary, fecal or sexual concerns.


Asunto(s)
Infertilidad Masculina/etiología , Disfunciones Sexuales Fisiológicas/etiología , Anomalías Urogenitales/complicaciones , Extrofia de la Vejiga/complicaciones , Epispadias/complicaciones , Humanos , Hipospadias/complicaciones , Masculino , Disrafia Espinal/complicaciones
12.
J Nucl Cardiol ; 28(4): 1692-1701, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-31529384

RESUMEN

PURPOSE: Cardiac 123I-MIBG image interpretation is affected by population differences and technical factors. We recruited older adults without cognitive decline and compared their cardiac MIBG uptake with results from the literature. METHODS: Phantom calibration confirmed that cardiac uptake results from Japan could be applied to our center. We recruited 31 controls, 17 individuals with dementia with Lewy bodies (DLB) and 15 with Alzheimer's disease (AD). Images were acquired 20 minutes and four hours after injection using Siemens cameras with medium-energy low-penetration (MELP) collimators. Local normal heart-to-mediastinum (HMR) ratios were compared to Japanese results. RESULTS: Siemens gamma cameras with MELP collimators should give HMRs very close to the calibrated values used in Japan. However, our cut-offs with controls were lower at 2.07 for early and 1.86 for delayed images. Applying our lower cut-off to the dementia patients may increase the specificity of cardiac MIBG imaging for DLB diagnosis in a UK population without reducing sensitivity. CONCLUSIONS: Our local HMR cut-off values are lower than in Japan, higher than in a large US study but similar to those found in another UK center. UK centers using other cameras and collimators may need to use different cut-offs to apply our results.


Asunto(s)
3-Yodobencilguanidina/farmacocinética , Enfermedad de Alzheimer/metabolismo , Radioisótopos de Yodo/farmacocinética , Enfermedad por Cuerpos de Lewy/metabolismo , Radiofármacos/metabolismo , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico por imagen , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Humanos , Enfermedad por Cuerpos de Lewy/diagnóstico por imagen , Masculino , Persona de Mediana Edad
13.
Nature ; 519(7543): 344-8, 2015 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-25788097

RESUMEN

Atmospheric carbon dioxide records indicate that the land surface has acted as a strong global carbon sink over recent decades, with a substantial fraction of this sink probably located in the tropics, particularly in the Amazon. Nevertheless, it is unclear how the terrestrial carbon sink will evolve as climate and atmospheric composition continue to change. Here we analyse the historical evolution of the biomass dynamics of the Amazon rainforest over three decades using a distributed network of 321 plots. While this analysis confirms that Amazon forests have acted as a long-term net biomass sink, we find a long-term decreasing trend of carbon accumulation. Rates of net increase in above-ground biomass declined by one-third during the past decade compared to the 1990s. This is a consequence of growth rate increases levelling off recently, while biomass mortality persistently increased throughout, leading to a shortening of carbon residence times. Potential drivers for the mortality increase include greater climate variability, and feedbacks of faster growth on mortality, resulting in shortened tree longevity. The observed decline of the Amazon sink diverges markedly from the recent increase in terrestrial carbon uptake at the global scale, and is contrary to expectations based on models.


Asunto(s)
Dióxido de Carbono/análisis , Secuestro de Carbono , Bosque Lluvioso , Atmósfera/química , Biomasa , Brasil , Carbono/análisis , Carbono/metabolismo , Dióxido de Carbono/metabolismo , Tallos de la Planta/metabolismo , Árboles/crecimiento & desarrollo , Árboles/metabolismo , Clima Tropical , Madera/análisis
14.
J Sports Sci ; 39(16): 1838-1849, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33759688

RESUMEN

We quantified on pitch external loading of English Premier League (EPL) academy soccer players (n=76; U12-U18 age groups) over an entire competitive season. Mean accumulative weekly duration and total distance, respectively, was similar in the U12 (329±29 min; 19.9±2.2 km), U13 (323±29 min; 20.0±2.0 km) and U14 (339±25 min; 21.7±2.0 km; P>0.05 for all comparisons) age-groups, though all teams were less than U15 (421±15 min; 26.2±2.1 km), U16 (427±20 min; 25.9±2.5 km) and U18 (398±30 min; 26.1±2.6 km) players (P<0.05 for all comparisons). Mean weekly high-speed running and sprint distance was not different between U12 (220±95 m and 6±9 m respectively), U13 (331±212 m and 6±27 m) and U14 (448±193 m and 21±29 m) age-groups (P>0.05 for all pairwise comparisons) though all squads were less than U15 (657±242 m and 49±98 m), U16 (749±152 m and 95±55 m) and U18 (979±254 m and 123±56 m) age-groups (P<0.05 for all pairwise comparisons). Data demonstrate that absolute weekly training volume in EPL academy soccer players increases throughout the academy pathway. Furthermore, although U16-U18 players are capable of achieving similar training and match volumes as previously reported in adult EPL players, they do not yet achieve the absolute intensities of adult EPL players.


Asunto(s)
Rendimiento Atlético/fisiología , Carrera/fisiología , Fútbol/fisiología , Adolescente , Factores de Edad , Niño , Sistemas de Información Geográfica , Humanos , Masculino , Estaciones del Año
15.
Eur Respir J ; 55(1)2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31672759

RESUMEN

The mechanisms by which cigarette smoking impairs airway mucus clearance are not well understood. We recently established a ferret model of cigarette smoke-induced chronic obstructive pulmonary disease (COPD) exhibiting chronic bronchitis. We investigated the effects of cigarette smoke on mucociliary transport (MCT).Adult ferrets were exposed to cigarette smoke for 6 months, with in vivo mucociliary clearance measured by technetium-labelled DTPA retention. Excised tracheae were imaged with micro-optical coherence tomography. Mucus changes in primary human airway epithelial cells and ex vivo ferret airways were assessed by histology and particle tracking microrheology. Linear mixed models for repeated measures identified key determinants of MCT.Compared to air controls, cigarette smoke-exposed ferrets exhibited mucus hypersecretion, delayed mucociliary clearance (-89.0%, p<0.01) and impaired tracheal MCT (-29.4%, p<0.05). Cholinergic stimulus augmented airway surface liquid (ASL) depth (5.8±0.3 to 7.3±0.6 µm, p<0.0001) and restored MCT (6.8±0.8 to 12.9±1.2 mm·min-1, p<0.0001). Mixed model analysis controlling for covariates indicated smoking exposure, mucus hydration (ASL) and ciliary beat frequency were important predictors of MCT. Ferret mucus was hyperviscous following smoke exposure in vivo or in vitro, and contributed to diminished MCT. Primary cells from smokers with and without COPD recapitulated these findings, which persisted despite the absence of continued smoke exposure.Cigarette smoke impairs MCT by inducing airway dehydration and increased mucus viscosity, and can be partially abrogated by cholinergic secretion of fluid secretion. These data elucidate the detrimental effects of cigarette smoke exposure on mucus clearance and suggest additional avenues for therapeutic intervention.


Asunto(s)
Deshidratación , Enfermedad Pulmonar Obstructiva Crónica , Adulto , Humanos , Depuración Mucociliar , Moco , Fumar/efectos adversos , Viscosidad
16.
Opt Lett ; 45(20): 5879, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-33057308

RESUMEN

The referenced article [Opt. Lett.43, 4615 (2018)OPLEDP0146-959210.1364/OL.43.004615] has been retracted by the authors.

17.
Langmuir ; 36(6): 1596-1607, 2020 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-32026679

RESUMEN

Painted environmental surfaces are prone to microbiological colonization with potential coating deterioration induced by the microorganisms. Accurate mechanistic models of these interactions require an understanding of the heterogeneity in which the deterioration processes proceed. Here, unsaturated biofilms (i.e., at air/solid interfaces) of the yeast Papiliotrema laurentii were prepared on polyether polyurethane (PEUR) and polyester-polyether polyurethane (PEST-PEUR) coatings and incubated for up to 33 days at controlled temperature and humidity with no additional nutrients. Transmission micro-Fourier transform infrared microscopy (µFTIR) confirmed preferential hydrolysis of the ester component by the biofilm. Atomic force microscopy combined with infrared nanospectroscopy (AFM-IR) was used to analyze initial PEST-PEUR coating deterioration processes at the single-cell level, including underlying surfaces that became exposed following cell translocation. The results revealed distinct deterioration features that remained localized within ∼10 µm or less of the edges of individual cells and cell clusters. These features comprised depressions of up to ∼300 nm with locally reduced ester/urethane ratios. They are consistent with a formation process initiated by enzymatic ester hydrolysis followed by erosion from water condensation cycles. Further observations included particle accumulation in the broader biofilm vicinity. AFM-IR spectroscopy indicated these to be secondary microplastics consisting of urethane-rich oligomeric aggregates. Overall, multiple contributing factors have been identified that can facilitate differential deterioration rates across the PEST-PEUR surface. Effects of the imposed nutrient conditions on Papiliotrema laurentii physiology were also apparent, with cells developing the characteristics of starvation response, despite the availability of polyester metabolites as a carbon source. The combined results provide new laboratory insights into field-relevant microbiological polymer deterioration mechanisms and biofilm physiology at polymer coating interfaces.


Asunto(s)
Microplásticos , Poliuretanos , Basidiomycota , Biopelículas , Plásticos
18.
J Sex Med ; 17(9): 1665-1675, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32444342

RESUMEN

BACKGROUND: The psychosexual outcome in adolescents and young adults (AYA) men born with hypospadias is precarious. However, the factors responsible for impaired outcome in some AYA men have been understudied. AIM: To explore the outcome after hypospadias repair in childhood of AYA men aged 16-21 years and examine their opinion and their parents' opinion about this type of surgery. METHODS: Cross-sectional assessment of 193 AYA men born with hypospadias and 50 male controls was performed. Questionnaires such as the Decision Regret Scale, Pediatric Penile Perception Score, Sexual Quality of Life-Male, International Index of Erectile Function, and a custom-made questionnaire were used. The Decision Regret Scale and a custom-made questionnaire were also completed by the participants' parents. Physical examination including Hypospadias Objective Penile Evaluation and measuring stretched penile length was performed. OUTCOMES: This study reports the psychosexual functioning (ie, social, relational, and sexual), erectile and sexual function after childhood hypospadias repair, using ad hoc measures. In addition, the opinion about hypospadias repair of patients and their parents is represented. RESULTS: The number of surgeries and satisfaction regarding penile appearance were the most important factors associated with the opinion on hypospadias repair and the psychosexual outcome. Most AYA men were more satisfied with their penile appearance than the physician. 80% of men were satisfied with having had a childhood hypospadias repair, even though they had not been able to consent to surgery themselves. Erectile and ejaculation problems were mild and seen in approximately 10% of the population. CLINICAL IMPLICATIONS: Based on our data, deferring hypospadias repair until the patient can decide himself is not warranted. However, physicians who accept a suboptimal esthetic outcome and withdraw from repeated surgery may contribute importantly to the patient's well-being, especially in proximal forms of hypospadias. STRENGTHS & LIMITATIONS: This is one of the rare studies addressing the AYA's psychosexual outcome after childhood hypospadias repair. Strengths include the combination of clinical and psychosexual data from a very large cohort of men and their parents to provide a more holistic view. By entering this study, participants might have a different comfort level regarding their sexuality or have a different body image than the overall population of young men. CONCLUSION: Uncomplicated hypospadias surgery results in equal psychosexual outcome as controls and in high satisfaction rates; multiple surgeries are a risk factor for poorer outcomes. 80% of men are satisfied with childhood hypospadias repair. Tack LJW, Springer A, Riedl S, et al. Psychosexual Outcome, Sexual Function, and Long-Term Satisfaction of Adolescent and Young Adult Men After Childhood Hypospadias Repair. J Sex Med 2020;17:1665-1675.


Asunto(s)
Hipospadias , Adolescente , Adulto , Niño , Estudios Transversales , Humanos , Hipospadias/cirugía , Masculino , Satisfacción del Paciente , Satisfacción Personal , Calidad de Vida , Conducta Sexual , Encuestas y Cuestionarios , Adulto Joven
19.
Nature ; 506(7486): 76-80, 2014 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-24499918

RESUMEN

Feedbacks between land carbon pools and climate provide one of the largest sources of uncertainty in our predictions of global climate. Estimates of the sensitivity of the terrestrial carbon budget to climate anomalies in the tropics and the identification of the mechanisms responsible for feedback effects remain uncertain. The Amazon basin stores a vast amount of carbon, and has experienced increasingly higher temperatures and more frequent floods and droughts over the past two decades. Here we report seasonal and annual carbon balances across the Amazon basin, based on carbon dioxide and carbon monoxide measurements for the anomalously dry and wet years 2010 and 2011, respectively. We find that the Amazon basin lost 0.48 ± 0.18 petagrams of carbon per year (Pg C yr(-1)) during the dry year but was carbon neutral (0.06 ± 0.1 Pg C yr(-1)) during the wet year. Taking into account carbon losses from fire by using carbon monoxide measurements, we derived the basin net biome exchange (that is, the carbon flux between the non-burned forest and the atmosphere) revealing that during the dry year, vegetation was carbon neutral. During the wet year, vegetation was a net carbon sink of 0.25 ± 0.14 Pg C yr(-1), which is roughly consistent with the mean long-term intact-forest biomass sink of 0.39 ± 0.10 Pg C yr(-1) previously estimated from forest censuses. Observations from Amazonian forest plots suggest the suppression of photosynthesis during drought as the primary cause for the 2010 sink neutralization. Overall, our results suggest that moisture has an important role in determining the Amazonian carbon balance. If the recent trend of increasing precipitation extremes persists, the Amazon may become an increasing carbon source as a result of both emissions from fires and the suppression of net biome exchange by drought.


Asunto(s)
Atmósfera/química , Ciclo del Carbono , Sequías/estadística & datos numéricos , Biomasa , Biota , Brasil , Dióxido de Carbono/análisis , Monóxido de Carbono/análisis , Incendios/estadística & datos numéricos , Agua Dulce/análisis , Fotosíntesis , Lluvia , Estaciones del Año , Árboles/metabolismo , Clima Tropical
20.
Public Health ; 182: 116-124, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32259722

RESUMEN

OBJECTIVE: To examine the effectiveness of interventions using the World Health Organization Health Promoting Schools (HPSs) framework approach in increasing physical activity (PA) and improving the diet of 11-18-year-olds. STUDY DESIGN: A systematic review guided by the National Health Services Centre for Reviews and Dissemination framework and reported in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses. METHODS: Nine databases and trial registries were searched from 2013 to 2018 for cluster randomised controlled trials involving adolescents' aged 11-18 years. We also included relevant studies from a 2014 Cochrane Review of HPS approach on health behaviours. Data were extracted from included studies and assessed for quality. RESULTS: Twelve eligible studies were identified from seven countries. The studies varied in outcome measures, sample size, quality and duration of intervention and follow-up. Only four of the included studies were of high to moderate quality. We found some evidence of effectiveness for physical activity only interventions and limited evidence of effectiveness for nutrition only and combined PA and nutrition interventions. CONCLUSIONS: There were no discernible patterns across the studies to suggest effective mechanisms for the HPS approach. The family/community component was poorly developed and superficially reported in all studies. Future research should seek to understand how best to work in partnership with secondary schools, to foster and sustain a healthy eating and physical activity culture, which aligns with their core aims. More attention should be paid to the restriction of unhealthy foods in the school environment.


Asunto(s)
Dieta , Ejercicio Físico , Promoción de la Salud , Servicios de Salud Escolar , Instituciones Académicas , Adolescente , Niño , Dieta Saludable , Conductas Relacionadas con la Salud , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudiantes , Organización Mundial de la Salud
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