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1.
Int J Mol Sci ; 25(4)2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38397027

RESUMEN

A feature of the SARS-CoV-2 Omicron subvariants BF.5 and BF.7 that recently circulated mainly in China and Japan was the high prevalence of the ORF7a: H47Y mutation, in which the 47th residue of ORF7a has been mutated from a histidine (H) to a tyrosine (Y). Here, we evaluated the effect of this mutation on the three main functions ascribed to the SARS-CoV-2 ORF7a protein. Our findings show that H47Y mutation impairs the ability of SARS-CoV-2 ORF7a to antagonize the type I interferon (IFN-I) response and to downregulate major histocompatibility complex I (MHC-I) cell surface levels, but had no effect in its anti-SERINC5 function. Overall, our results suggest that the H47Y mutation of ORF7a affects important functions of this protein, resulting in changes in virus pathogenesis.


Asunto(s)
COVID-19 , Interferón Tipo I , Humanos , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , COVID-19/genética , Interferón Tipo I/metabolismo , Mutación , China
2.
Eur J Orthop Surg Traumatol ; 34(3): 1253-1258, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38085371

RESUMEN

This review presents the principal features of paediatric femoral shaft fractures including the contemporary management strategies and relevant supporting evidence. The article is an overview of information relevant to clinical practice, in addition to preparation for the FRCS (Orth) examination.


Asunto(s)
Fracturas del Fémur , Humanos , Niño , Fracturas del Fémur/diagnóstico , Fracturas del Fémur/cirugía , Estudios Retrospectivos
3.
Biochemistry ; 61(2): 57-66, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-34979083

RESUMEN

The improper maintenance of the bioactivated form of vitamin-D (1α,25(OH)2D) may result in vitamin-D insufficiency and therefore compromise the absorption of dietary calcium. A significant regulator of vitamin-D metabolism is the inactivating function of the mitochondrial enzyme cytochrome P450 24A1 (CYP24A1). In humans, CYP24A1 carries out hydroxylation of carbon-23 (C23) or carbon-24 (C24) of the 1α,25(OH)2D side chain, eventually resulting in production of either an antagonist of the vitamin-D receptor (C23 pathway) or calcitroic acid (C24 pathway). Despite its importance to human health, the human isoform (hCYP24A1) remains largely uncharacterized due in part to the difficulty in producing the enzyme using recombinant means. In this study, we utilize a cleavable fusion with the cognate redox partner, human Adx (hAdx), to stabilize hCYP24A1 during production. The subsequent cleavage and isolation of active hCYP24A1 allowed for an investigation of substrate and analog binding, enzymatic activity, and redox partner recognition. We demonstrate involvement of a nonpolar contact involving Leu-80 of hAdx and a nonconserved proximal surface of hCYP24A1. Interestingly, shortening the length of this residue (L80V) results in enhanced binding between the CYP-Adx complex and 1α,25(OH)2D yet unexpectedly results in decreased catalysis. The same mutation has a negligible effect on rat CYP24A1 (a C24-hydroxylase), indicating the presence of a species-specific requirement that may correlate with differences in regioselectivity of the reaction. Taken together, this work presents an example of production of a challenging human CYP as well as providing details regarding hydrophobic modulation of a CYP-Adx complex that is critical to human vitamin-D metabolism.


Asunto(s)
Adrenodoxina/metabolismo , Vitamina D3 24-Hidroxilasa/metabolismo , Vitamina D/metabolismo , Adrenodoxina/química , Sitios de Unión , Humanos , Hidroxilación , Oxidación-Reducción , Unión Proteica , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismo , Especificidad por Sustrato , Vitamina D/química , Vitamina D3 24-Hidroxilasa/química
4.
Int Orthop ; 46(1): 143-152, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34655318

RESUMEN

BACKGROUND AND BURDEN: Trauma with its early and late consequences disproportionately effects those from poor countries. The availability of effective orthopaedic and trauma care varies significantly across the globe. CHALLENGES: The balancing out of quality care is required to reach the health-related UN development goal set out in 2015. A multifactorial approach addressing local, national and international aspects is key to improving the discrepancy seen between high- and low-income countries.


Asunto(s)
Servicios Médicos de Urgencia , Ortopedia , Países en Desarrollo , Humanos , Calidad de la Atención de Salud
5.
Eur J Orthop Surg Traumatol ; 31(5): 871-881, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33744996

RESUMEN

PURPOSE: Supracondylar fractures are common injuries accounting for approximately 15% of all fractures in children with a large body of literature on this subject. METHODS:  This article critically appraises the available evidence to provide an overview of the treatment options including the role and timing of surgery, the geometry of wire fixation and the management of nerve and arterial injury. CONCLUSION:  Management decisions are based on a number of considerations particularly fracture stability. Closed reduction and percutaneous K-wire stabilisation are commonly recommended for an unstable displaced fracture. These techniques are however associated with the potential for iatrogenic neurological injury. Vascular injury is also rare but must be recognised and treated promptly to avoid significant permanent morbidity.


Asunto(s)
Fracturas del Húmero , Lesiones del Sistema Vascular , Hilos Ortopédicos , Niño , Fijación Interna de Fracturas , Humanos , Fracturas del Húmero/diagnóstico por imagen , Fracturas del Húmero/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Lesiones del Sistema Vascular/etiología , Lesiones del Sistema Vascular/cirugía
6.
Eur J Orthop Surg Traumatol ; 31(5): 883-892, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33839930

RESUMEN

This article discusses the incidence, applied anatomy and classification of paediatric femoral fractures based on critical appraisal of the available evidence. The aim is to identify techniques that are relevant to contemporary practice whilst excluding the technical details of individual procedures that are beyond the scope of this review. Injuries of the proximal, diaphyseal and distal segments are considered individually as there are considerations that are specific to each anatomical site. Femoral neck fractures are rare injuries and require prompt anatomical reduction and stable fixation to minimise the potentially devastating consequences of avascular necrosis. Diaphyseal fractures are relatively common, and there is a spectrum of management options that depend on patient age and size. Distal femoral fractures often involve the physis, which contributes up to 70% of femoral length. Growth arrest is common consequence of fractures in this region, resulting in angular and length-related deformity. Long-term surveillance is recommended to identify deformity in evolution and provide an opportunity for early intervention. Deliberate injury should be considered in all fractures, particularly distal femoral physeal injuries and fractures in the non-walking child.


Asunto(s)
Fracturas del Fémur , Fracturas del Cuello Femoral , Niño , Fracturas del Fémur/cirugía , Fémur , Placa de Crecimiento , Humanos , Estudios Retrospectivos
7.
Respir Res ; 18(1): 124, 2017 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-28629419

RESUMEN

BACKGROUND: Beta-blockers are commonly prescribed for patients with cardiovascular disease. Providers have been wary of treating chronic obstructive pulmonary disease (COPD) patients with beta-blockers due to concern for bronchospasm, but retrospective studies have shown that cardio-selective beta-blockers are safe in COPD and possibly beneficial. However, these benefits may reflect symptom improvements due to the cardiac effects of the medication. The purpose of this study is to evaluate associations between beta-blocker use and both exacerbation rates and longitudinal measures of lung function in two well-characterized COPD cohorts. METHODS: We retrospectively analyzed 1219 participants with over 180 days of follow up from the STATCOPE trial, which excluded most cardiac comorbidities, and from the placebo arm of the MACRO trial. Primary endpoints were exacerbation rates per person-year and change in spirometry over time in association with beta blocker use. RESULTS: Overall 13.9% (170/1219) of participants reported taking beta-blockers at enrollment. We found no statistically significant differences in exacerbation rates with respect to beta-blocker use regardless of the prevalence of cardiac comorbidities. In the MACRO cohort, patients taking beta-blockers had an exacerbation rate of 1.72/person-year versus a rate of 1.71/person-year in patients not taking beta-blockers. In the STATCOPE cohort, patients taking beta-blockers had an exacerbation rate of 1.14/person-year. Patients without beta-blockers had an exacerbation rate of 1.34/person-year. We found no detrimental effect of beta blockers with respect to change in lung function over time. CONCLUSION: We found no evidence that beta-blocker use was unsafe or associated with worse pulmonary outcomes in study participants with moderate to severe COPD.


Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Pulmón/efectos de los fármacos , Pulmón/fisiología , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Antagonistas Adrenérgicos beta/farmacología , Anciano , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Pruebas de Función Respiratoria/métodos , Estudios Retrospectivos , Resultado del Tratamiento
12.
bioRxiv ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38915642

RESUMEN

The fungus Cryptococcus neoformans is an opportunistic pathogen of people that reprograms its translatome to facilitate adaptation and virulence within the host. We studied the role of Hog1/p38 in reprogramming translation during thermal stress adaptation, and found that this pathway acts on translation via crosstalk with the Gcn2 pathway, a well-studied regulator of general translation control. Using a combination of molecular assays and phenotypic analysis, we show that increased output from the Gcn2 pathway in a Hog1 deletion mutant is associated with rescue of thermal stress adaptation at both molecular and phenotypic scales. We characterize known outputs of the Hog1 pathway during thermal stress as either Gcn2-dependent or Gcn2-independent, and demonstrate that Hog1 activation regulates the Gcn2 pathway even in the absence of thermal stress. Finally, we implicate this phenomenon in another Hog1-regulated process, morphogenesis, and recapitulate Hog1-Gcn2 crosstalk in the distantly related fungal pathogen, Candida albicans. Our results point to an important link between the stress response machinery and translation control, and clarify the etiology of phenotypes associated with Hog1 deletion. More broadly, this study highlights complex interplay between core conserved signal transduction pathways and the utility of molecular assays to better understand how these pathways are connected.

13.
Materials (Basel) ; 17(13)2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38998244

RESUMEN

Additively manufactured implants, surgical guides, and medical devices that would have direct contact with the human body require predictable behaviour when stress is applied during their standard operation. Products built with Fused Filament Fabrication (FFF) possess orthotropic characteristics, thus, it is necessary to determine the properties that can be achieved in the XY- and Z-directions of printing. A concentration of 10 wt% of hydroxyapatite (HA) in polyetherketoneketone (PEKK) matrix was selected as the most promising biomaterial supporting cell attachment for medical applications and was characterized with an Ultimate Tensile Strength (UTS) of 78.3 MPa and 43.9 MPa in the XY- and Z-directions of 3D printing, respectively. The effect of the filler on the crystallization kinetics, which is a key parameter for the selection of semicrystalline materials suitable for 3D printing, was explained. This work clearly shows that only in situ crystallization provides the ability to build parts with a more thermodynamically stable primary form of crystallites.

14.
Gynecol Oncol ; 131(3): 613-8, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24076063

RESUMEN

OBJECTIVE: Excessive oestrogenic stimulation is a well-known risk factor for the development and progression of endometrial cancer. Aromatase is the key enzyme which catalyses the conversion of androgens to oestrogens in postmenopausal women. Inhibition of aromatase may therefore be a useful strategy in the management of endometrial cancer. A pilot study was designed to assess the feasibility of a neoadjuvant model and understand the biological effects of anastrozole, an aromatase inhibitor, in the treatment of endometrial cancer. METHODS: Patients with endometrial cancer who consented to participate in the study were randomised to receive anastrozole or placebo for a minimum of 14 days prior to definitive surgery. Endometrial samples were obtained before and after treatment. Immunohistochemistry was performed to ascertain the expression of oestrogen receptor alpha (ERα), progesterone receptor (PR), androgen receptor (AR), ki-67 and Bcl2 before and after treatment in glands and stroma of the endometrium. RESULTS: A total of 16 patients were randomised to the anastrozole arm and 8 to the placebo arm (2:1 randomisation). A significant decrease in the glandular expression of ERα and AR was observed in the anastrozole arm. There was no significant change in the expression of PR or Bcl2. Expression of ki-67, a proliferation marker, also decreased significantly following treatment with anastrozole. CONCLUSIONS: Treatment with anastrozole caused a significant decrease in proliferation as demonstrated by decreased ki-67 expression. A large randomised controlled trial is warranted to fully assess the role of anastrozole in the neoadjuvant treatment of endometrial cancer.


Asunto(s)
Neoplasias Endometriales/tratamiento farmacológico , Nitrilos/uso terapéutico , Triazoles/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Anastrozol , Antineoplásicos Hormonales/uso terapéutico , Inhibidores de la Aromatasa/uso terapéutico , Procesos de Crecimiento Celular/efectos de los fármacos , Neoplasias Endometriales/metabolismo , Neoplasias Endometriales/patología , Neoplasias Endometriales/cirugía , Receptor alfa de Estrógeno/biosíntesis , Femenino , Humanos , Inmunohistoquímica , Antígeno Ki-67/biosíntesis , Persona de Mediana Edad , Terapia Neoadyuvante , Proyectos Piloto , Placebos , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Receptores de Progesterona/biosíntesis
15.
Bone Jt Open ; 4(12): 964-969, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38112276

RESUMEN

Aims: We assessed the long-term outcomes of a large cohort of patients who have undergone a periacetabular osteotomy (PAO), and sought to validate a patient satisfaction questionnaire for use in a PAO cohort. Methods: All patients who had undergone a PAO from July 1998 to February 2013 were surveyed, with several patient-reported outcome measures (PROMs) and radiological measurements of preoperative acetabular dysplasia and postoperative correction also recorded. Patients were asked to rate their level of satisfaction with their operation in achieving pain relief, restoration of activities of daily living, ability to perform recreational activity, and their overall level of satisfaction with the procedure. Results: A total of 143 PAOs were performed between 1998 and 2013. Of those, 90 postoperative surveys were returned. Only 65 patients (73 hips) had both pre- and postoperative radiographs available for measurement. The mean time to follow-up was 15 years (6.5 to 20). Most patients were female (91%), with a mean age of 26.4 years (14.9 to 48.3) at the time of their surgery. A statistically significant improvement in radiological correction was detected in all hips (p < 0.001). A total of 67 patients (92.3%) remained either very satisfied or satisfied with their PAO. The internal consistency of the patient satisfaction questionnaire, measured using Cronbach's α, ranged from 0.89 to 0.94 indicating 'good' to 'excellent' reliability. Conclusion: Outcomes of importance to patients undergoing a PAO include several key domains: pain relief, improve activities of daily living, and improve recreational ability. Our study demonstrates high rates of long-term patient satisfaction in all domains, and found the patient satisfaction questionnaire to be a valid and reliable instrument for use in this cohort.

16.
Pract Anthropol ; 44(3): 20-29, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36382342

RESUMEN

In rural, Indigenous Guatemala, women's healthcare is fragmented and inadequate. Our interdisciplinary, multinational research team aimed to 1) describe reproductive health in one rural Indigenous community; 2) explore contraceptive use; and 3) learn about and prioritize Indigenous Maya women's reproductive health beliefs and needs. Our study team conducted mixed-methods surveys with 62 women, led focus groups with 20 community health workers, and analyzed data using concurrent mixed methods analysis. We found that 51% of women surveyed reported current family planning, with 33% using a biomedical method. We found high mean fertility, 6.9 live births per woman aged 40-49 (national average 4.7), with significant socioeconomic variation. We also found that poverty correlated with total fertility, while education inversely correlated. Our research found that contraceptive use had a strong association with access to healthcare and with women's reported sexual autonomy (which we instrumentalized based on women's answers to the question "can you refuse to have sex with your husband?"). Many women we spoke to feared contraception, specifically concerned it could cause cancer. Overall, Guatemalan Indigenous women expressed unease seeking reproductive healthcare within health systems that have historically and currently excluded and mistreated Indigenous communities. Our research documented unexplored influences on contraceptive use, including the relationship between sexual autonomy and contraception and widespread concern of cancer with contraceptive use. We conclude, moving forward, that we and other researchers should continue to collaborate with communities to improve Indigenous women's reproductive healthcare.

17.
Cortex ; 153: 87-96, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35635860

RESUMEN

Kording and Wolpert (2004), hereafter referred to as KW, describe an experiment where subjects strove for accuracy in a stochastic environment and, on some trials, received mid-trial and post-trial feedback. KW claims that subjects learned the underlying stochastic distribution from the post-trial feedback of previous trials. KW also claims that subjects regarded mid-trial feedback that had a smaller visual size as more precise and they were therefore more sensitive to such mid-trial feedback. KW concludes that the observations are consistent with optimal Bayesian learning. KW has become an extremely influential paper in the large literature arguing that subjects are optimal Bayesian learners in stochastic environments. It is therefore crucial that the KW conclusions follow from their dataset. We note that KW analyzes data that have been both averaged across trials and averaged across other important trial-specific details. We also note that KW mischaracterizes the accuracy of the mid-trial feedback and the relative sizes of the mid-trial feedback. When we analyze the trial-level KW data, we do not find that subjects were more sensitive to mid-trial feedback when it had a smaller visual size. Our trial-level analysis also suggests a recency bias, rather than evidence that the subjects learned the stochastic distribution. In other words, we do not find that the observations are consistent with optimal Bayesian learning. In the KW dataset, it seems that evidence for optimal Bayesian learning is a statistical artifact of analyzing averaged data. Our results from the KW dataset would seem to have important implications for the literature on Bayesian judgments.


Asunto(s)
Retroalimentación Sensorial , Aprendizaje , Teorema de Bayes , Humanos
18.
Phys Rev E ; 106(1-1): 014801, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35974555

RESUMEN

Embioptera (webspinners) are insects that construct domiciles using silk produced from their front feet. This silk is the finest known with measured single fiber diameters in the 30-140 nm range. In the wild, some webspinner silk on trees is observed to have a clothlike or shiny sheetlike appearance. Both forms of silk shield the occupants from rain water effectively: presumably valuable in tropical environments. In this article we elucidate the mechanism by which silk fibers are transformed into these structures through interaction with water. We quantify the evaporation rates of single water droplets which have been suspended on unmodified as-spun silk for two Trinidadian arboreal species: Antipaluria urichi (Clothodidae) and Pararhagadochir trinitatis (Scelembiidae). These rates are compared to those of droplets suspended on rose petals due to similar wetting properties (both hydrophobicity and pinning). We observe that on sufficiently thick silk, droplet evaporation rates decrease with time. This behavior is a result of a thin soluble film developing on the drop surface that later becomes a solid residual film. Experimentally verified theoretical models are invoked to support the results.

19.
BMJ Open ; 12(4): e053590, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35365520

RESUMEN

OBJECTIVES: To develop and validate tests to assess the risk of any cancer for patients referred to the NHS Urgent Suspected Cancer (2-week wait, 2WW) clinical pathways. SETTING: Primary and secondary care, one participating regional centre. PARTICIPANTS: Retrospective analysis of data from 371 799 consecutive 2WW referrals in the Leeds region from 2011 to 2019. The development cohort was composed of 224 669 consecutive patients with an urgent suspected cancer referral in Leeds between January 2011 and December 2016. The diagnostic algorithms developed were then externally validated on a similar consecutive sample of 147 130 patients (between January 2017 and December 2019). All such patients over the age of 18 with a minimum set of blood counts and biochemistry measurements available were included in the cohort. PRIMARY AND SECONDARY OUTCOME MEASURES: sensitivity, specificity, negative predictive value, positive predictive value, Receiver Operating Characteristic (ROC) curve Area Under Curve (AUC), calibration curves RESULTS: We present results for two clinical use-cases. In use-case 1, the algorithms identify 20% of patients who do not have cancer and may not need an urgent 2WW referral. In use-case 2, they identify 90% of cancer cases with a high probability of cancer that could be prioritised for review. CONCLUSIONS: Combining a panel of widely available blood markers produces effective blood tests for cancer for NHS 2WW patients. The tests are affordable, and can be deployed rapidly to any NHS pathology laboratory with no additional hardware requirements.


Asunto(s)
Aprendizaje Automático , Neoplasias , Adulto , Algoritmos , Humanos , Persona de Mediana Edad , Neoplasias/diagnóstico , Neoplasias/epidemiología , Atención Primaria de Salud , Derivación y Consulta , Estudios Retrospectivos
20.
Anal Biochem ; 416(1): 123-5, 2011 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-21624343

RESUMEN

Laser capture microdissection of frozen tissue sections allows homogeneous cell populations to be isolated for expression profiling. However, this requires striking a balance between retaining adequate morphology for accurate microdissection and maintaining RNA integrity. Various staining protocols were applied to frozen endometrial carcinoma tissue sections. Although alcohol-based methods were superior to aqueous stains for maintaining RNA integrity, they suffered from irreproducible staining intensity. We developed a modified alcohol-based, buffered cresyl violet staining protocol that provides reproducible staining with minimal RNA degradation suitable for tissues with moderate to high levels of intrinsic RNase activity.


Asunto(s)
Carcinoma Endometrioide/patología , Neoplasias Endometriales/patología , Secciones por Congelación , Rayos Láser , Microdisección , ARN Neoplásico/análisis , Coloración y Etiquetado/métodos , Carcinoma Endometrioide/genética , Neoplasias Endometriales/genética , Femenino , Humanos , ARN Neoplásico/genética , ARN Neoplásico/metabolismo
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