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1.
Genes Dev ; 35(9-10): 619-634, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33888561

RESUMEN

Development of the ovary or testis is required to establish reproductive competence. Gonad development relies on key cell fate decisions that occur early in embryonic development and are actively maintained. During gonad development, both germ cells and somatic cells proliferate extensively, a process facilitated by cell cycle regulation. This review focuses on the Cip/Kip family of cyclin-dependent kinase inhibitors (CKIs) in mouse gonad development. We particularly highlight recent single-cell RNA sequencing studies that show the heterogeneity of cyclin-dependent kinase inhibitors. This diversity highlights new roles for cell cycle inhibitors in controlling and maintaining female fertility.


Asunto(s)
Puntos de Control del Ciclo Celular/genética , Fertilidad/genética , Gónadas/crecimiento & desarrollo , Animales , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Diferenciación Celular/genética , Gónadas/metabolismo , Ratones , Procesos de Determinación del Sexo/genética , Análisis de la Célula Individual
2.
Am J Hum Genet ; 109(9): 1667-1679, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-36055213

RESUMEN

African populations are the most diverse in the world yet are sorely underrepresented in medical genetics research. Here, we examine the structure of African populations using genetic and comprehensive multi-generational ethnolinguistic data from the Neuropsychiatric Genetics of African Populations-Psychosis study (NeuroGAP-Psychosis) consisting of 900 individuals from Ethiopia, Kenya, South Africa, and Uganda. We find that self-reported language classifications meaningfully tag underlying genetic variation that would be missed with consideration of geography alone, highlighting the importance of culture in shaping genetic diversity. Leveraging our uniquely rich multi-generational ethnolinguistic metadata, we track language transmission through the pedigree, observing the disappearance of several languages in our cohort as well as notable shifts in frequency over three generations. We find suggestive evidence for the rate of language transmission in matrilineal groups having been higher than that for patrilineal ones. We highlight both the diversity of variation within Africa as well as how within-Africa variation can be informative for broader variant interpretation; many variants that are rare elsewhere are common in parts of Africa. The work presented here improves the understanding of the spectrum of genetic variation in African populations and highlights the enormous and complex genetic and ethnolinguistic diversity across Africa.


Asunto(s)
Variación Genética , Genética de Población , África Austral , Población Negra/genética , Estructuras Genéticas , Variación Genética/genética , Humanos
3.
Pflugers Arch ; 476(5): 847-859, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38421407

RESUMEN

Increases in the current threshold occur in optic nerve axons with the application of infra-red laser light, whose mechanism is only partly understood. In isolated rat optic nerve, laser light was applied near the site of electrical stimulation, via a flexible fibre optic. Paired applications of light produced increases in threshold that were reduced on the second application, the response recovering with increasing delays, with a time constant of 24 s. 3-min duration single applications of laser light gave rise to a rapid increase in threshold followed by a fade, whose time-constant was between 40 and 50 s. After-effects were sometimes apparent following the light application, where the resting threshold was reduced. The increase in threshold was partially blocked by 38.6 mM Li+ in combination with 5  µ M bumetanide, a manoeuvre increasing refractoriness and consistent with axonal depolarization. Assessing the effect of laser light on the nerve input resistance ruled out a previously suggested fall in myelin resistance as contributing to threshold changes. These data appear consistent with an axonal membrane potential that partly relies on temperature-dependent electroneutral Na+ influx, and where fade in the response to the laser may be caused by a gradually diminishing Na+ pump-induced hyperpolarization, in response to falling intracellular [Na+].


Asunto(s)
Axones , Rayos Láser , Nervio Óptico , Sodio , Animales , Ratas , Nervio Óptico/metabolismo , Sodio/metabolismo , Axones/metabolismo , Axones/fisiología , Axones/efectos de la radiación , Potenciales de la Membrana/fisiología , Masculino , Bumetanida/farmacología , Ratas Sprague-Dawley
4.
Mol Ther ; 31(7): 2056-2076, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-36905120

RESUMEN

Our research has proven that the inhibitory activity of the serine protease inhibitor neuroserpin (NS) is impaired because of its oxidation deactivation in glaucoma. Using genetic NS knockout (NS-/-) and NS overexpression (NS+/+ Tg) animal models and antibody-based neutralization approaches, we demonstrate that NS loss is detrimental to retinal structure and function. NS ablation was associated with perturbations in autophagy and microglial and synaptic markers, leading to significantly enhanced IBA1, PSD95, beclin-1, and LC3-II/LC3-I ratio and reduced phosphorylated neurofilament heavy chain (pNFH) levels. On the other hand, NS upregulation promoted retinal ganglion cell (RGC) survival in wild-type and NS-/- glaucomatous mice and increased pNFH expression. NS+/+Tg mice demonstrated decreased PSD95, beclin-1, LC3-II/LC3-I ratio, and IBA1 following glaucoma induction, highlighting its protective role. We generated a novel reactive site NS variant (M363R-NS) resistant to oxidative deactivation. Intravitreal administration of M363R-NS was observed to rescue the RGC degenerative phenotype in NS-/- mice. These findings demonstrate that NS dysfunction plays a key role in the glaucoma inner retinal degenerative phenotype and that modulating NS imparts significant protection to the retina. NS upregulation protected RGC function and restored biochemical networks associated with autophagy and microglial and synaptic function in glaucoma.


Asunto(s)
Glaucoma , Células Ganglionares de la Retina , Ratones , Animales , Células Ganglionares de la Retina/metabolismo , Beclina-1/metabolismo , Modelos Animales de Enfermedad , Glaucoma/genética , Glaucoma/terapia , Glaucoma/metabolismo , Apoptosis/genética , Presión Intraocular , Neuroserpina
5.
Pediatr Crit Care Med ; 25(3): 222-230, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37846938

RESUMEN

OBJECTIVES: Post-extubation stridor (PES) is difficult to predict before extubation. We therefore evaluated the potential diagnostic performance of pre-extubation laryngeal air column width difference (LACWD) measurement, as assessed by intensivist-performed point-of-care laryngeal ultrasound, in relation to clinically important PES. DESIGN: Prospective observational cohort study. SETTING: Single quaternary care PICU (July 19, 2021, to October 31, 2022). PATIENTS: Included subjects were younger than 5 years old, intubated with a cuffed endotracheal tube, requiring invasive mechanical ventilation for greater than 24 hours, and nearing extubation. Subjects at high risk for supraglottic airway obstruction were excluded. INTERVENTIONS: Laryngeal ultrasound with measurement of laryngeal air column width with the endotracheal tube cuff inflated and deflated. Clinically important PES was defined as a high-pitched inspiratory respiratory noise suspected to be from a subglottic focus necessitating received medical intervention or reintubation. MEASUREMENTS AND MAIN RESULTS: Among 53 enrolled subjects, 18 of 53 (34%) experienced PES and three of 53 (6%) were reintubated because of severe subglottic upper airway obstruction. Median LACWD was significantly lower in the stridor group compared with the nonstridor group (∆ 0.41 mm; 95% CI, 0.37-0.48; p < 0.001). The area under the receiver operating characteristic curve for LACWD as a diagnosis of PES was 0.94 (95% CI, 0.89-1.00; p < 0.001). The LACWD cutoff for PES was less than or equal to 0.47 mm, which yielded a diagnostic sensitivity of 91.4% and specificity of 88.9%. In this population, the pre-to-post-test change in probability of PES for LACWD less than or equal to 0.47 mm is 0.34 to 0.81. CONCLUSIONS: Pre-extubation LACWD is a novel, noninvasive assessment that can be performed and interpreted by the intensivist at the bedside. There is, however, diagnostic uncertainty in the use of this measurement for identifying those at-risk of PES and larger validation studies are needed.


Asunto(s)
Obstrucción de las Vías Aéreas , Ruidos Respiratorios , Humanos , Preescolar , Proyectos Piloto , Estudios Prospectivos , Ruidos Respiratorios/etiología , Extubación Traqueal/efectos adversos , Obstrucción de las Vías Aéreas/diagnóstico por imagen , Obstrucción de las Vías Aéreas/etiología , Intubación Intratraqueal/efectos adversos
6.
J Appl Clin Med Phys ; 25(1): e14235, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38059633

RESUMEN

PURPOSE: The purpose of this investigation was to assess the effect of visceral adipose tissue volume (VA) on reader efficacy in diagnosing and characterizing small bowel Crohn's disease using lower exposure CT enterography (CTE). Secondarily, we investigated the effect of lower exposure and VA on reader diagnostic confidence. METHODS: Prospective paired investigation of 256 CTE, 129 with Crohn's disease, were reconstructed at 100% and simulated 50% and 30% exposure. The senior author provided the disease classification for the 129 patients with Crohn's disease. Patient VA was measured, and exams were evaluated by six readers for presence or absence of Crohn's disease and phenotype using a 0-10-point scale. Logistic regression models assessed the effect of VA on sensitivity and specificity. RESULTS: The effect of VA on sensitivity was significantly reduced at 30% exposure (odds radio [OR]: 1.00) compared to 100% exposure (OR: 1.12) (p = 0.048). There was no statistically significant difference among the exposures with respect to the effect of visceral fat on specificity (p = 0.159). The study readers' probability of agreement with the senior author on disease classification was 60%, 56%, and 53% at 100%, 50%, and 30% exposure, respectively (p = 0.004). When detecting low severity Crohn's disease, readers' mean sensitivity was 83%, 75%, and 74% at 100%, 50%, and 30% exposure, respectively (p = 0.002). In low severity disease, sensitivity also tended to increase as visceral fat increased (ORs per 1000 cm3 increase in visceral fat: 1.32, 1.31, and 1.18, p = 0.010, 0.016, and 0.100, at 100%, 50%, and 30% exposure). CONCLUSIONS: While the interaction is complex, VA plays a role in detecting and characterizing small bowel Crohn's disease when exposure is altered, particularly in low severity disease.


Asunto(s)
Enfermedad de Crohn , Enfermedades Intestinales , Humanos , Enfermedad de Crohn/diagnóstico por imagen , Grasa Intraabdominal/diagnóstico por imagen , Estudios Prospectivos , Tomografía Computarizada por Rayos X/métodos
7.
J Med Syst ; 48(1): 24, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38386137

RESUMEN

BACKGROUND: Intraoperative neurophysiological monitoring (IOM) is a valuable adjunct for neurosurgical operative techniques, and has been shown to improve clinical outcomes in cranial and spinal surgery. It is not necessarily provided by NHS hospitals so may be outsourced to private companies, which are expensive and at cost to the NHS trusts. We discuss the benefits and challenges of developing an in-house service. METHODS: We surveyed NHS neurosurgical departments across England regarding their expenditure on IOM over the period January 2018 - December 2022 on cranial neurosurgery and spinal surgery. Out of 24 units, all responded to our Freedom of Information requests and 21 provided data. The standard NHS England salary of NHS staff who would normally be involved in IOM, including physiologists and doctors, was also compiled for comparison. RESULTS: The total spend on outsourced IOM, across the units who responded, was over £8 million in total for the four years. The annual total increased, between 2018 and 2022, from £1.1 to £3.5 million. The highest single unit yearly spend was £568,462. This is in addition to salaries for staff in neurophysiology departments. The mean NHS salaries for staff is also presented. CONCLUSION: IOM is valuable in surgical decision-making, planning, and technique, having been shown to lead to fewer patient complications and shorter length of stay. Current demand for IOM outstrips the internal NHS provision in many trusts across England, leading to outsourcing to private companies. This is at significant cost to the NHS. Although there is a learning curve, there are many benefits to in-house provision, such as stable working relationships, consistent methods, training of the future IOM workforce, and reduced long-term costs, which planned expansion of NHS services may provide.


Asunto(s)
Neurocirugia , Humanos , Monitoreo Intraoperatorio , Inglaterra , Gastos en Salud , Hospitales
8.
Biol Reprod ; 108(6): 854-865, 2023 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-36917225

RESUMEN

Organoid technology has provided a unique opportunity to study early human development and decipher various steps involved in the pathogenesis of disease. The technology is already used in clinics to improve human patient outcomes. However, limited knowledge of the methodologies required to establish organoid culture systems in domestic animals has slowed the advancement and application of organoid technology in veterinary medicine. This is particularly true for the field of reproduction and the application of assisted reproductive technologies (ART). Here, we have developed a platform to grow oviductal organoids from five domestic species-bovine, porcine, equine, feline, and canine. The organoids were grown progressively from single cells derived from the enzymatic digestion of freshly collected infundibular/fimbrial samples. The addition of WNT, TGFß, BMP, ROCK, and Notch signaling pathway activators or inhibitors to the organoid culture medium suggested remarkable conservation of the molecular signals involved in oviductal epithelial development and differentiation across species. The gross morphology of organoids from all the domestic species was initially similar. However, some differences in size, complexity, and growth rate were subsequently observed and described. After 21 days, well-defined and synchronized motile ciliated cells were observed in organoids. Histopathologically, oviductal organoids mimicked their respective native tissue. In summary, we have carried out a detailed cross-species comparison of oviductal organoids, which would be valuable in advancing our knowledge of oviduct physiology and, potentially, help in increasing the success of ART.


Asunto(s)
Organoides , Mascotas , Humanos , Femenino , Animales , Gatos , Bovinos , Caballos , Perros , Porcinos , Granjas , Trompas Uterinas , Diferenciación Celular
9.
Brief Bioinform ; 22(2): 1620-1638, 2021 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-32047889

RESUMEN

Statistically, accurate protein identification is a fundamental cornerstone of proteomics and underpins the understanding and application of this technology across all elements of medicine and biology. Proteomics, as a branch of biochemistry, has in recent years played a pivotal role in extending and developing the science of accurately identifying the biology and interactions of groups of proteins or proteomes. Proteomics has primarily used mass spectrometry (MS)-based techniques for identifying proteins, although other techniques including affinity-based identifications still play significant roles. Here, we outline the basics of MS to understand how data are generated and parameters used to inform computational tools used in protein identification. We then outline a comprehensive analysis of the bioinformatics and computational methodologies used in protein identification in proteomics including discussing the most current communally acceptable metrics to validate any identification.


Asunto(s)
Espectrometría de Masas/métodos , Proteínas/química , Proteómica/métodos , Cromatografía de Gases/métodos , Cromatografía Liquida/métodos , Biología Computacional/métodos
10.
HIV Med ; 24(5): 568-579, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36411596

RESUMEN

BACKGROUND: Limited data exist on pregnant women living with HIV exposed to cabotegravir + rilpivirine (CAB + RPV). Outcomes in pregnant participants exposed to CAB + RPV, and pharmacokinetic washout data in those exposed to CAB + RPV long-acting (LA) with live births, are presented. METHODS: Women exposed to one or more doses of CAB + RPV (oral/LA) from ViiV Healthcare-sponsored phase 2b/3/3b clinical trials and the compassionate use programme who became pregnant were included. Upon pregnancy in the trial programme, CAB + RPV was discontinued, an alternative antiretroviral regimen was initiated, and quarterly pharmacokinetic sampling for 52 weeks post-last injection was obtained. CAB + RPV continuation or alternative antiretroviral regimen initiation was decided by pregnant compassionate use programme participants and their treating physicians. RESULTS: As of 31 March 2021, 25 pregnancies following CAB + RPV exposure at conception were reported (five oral, 20 LA), including four who conceived during pharmacokinetic washout following treatment discontinuation. There were eight elective abortions, six miscarriages (five in first trimester), one ectopic pregnancy, and 10 live births (one oral, nine LA), including one infant born with congenital ptosis. Among participants exposed to CAB + RPV LA at conception with live births, plasma CAB and RPV washout concentrations during pregnancy were within the range of those observed in non-pregnant women. CONCLUSION: In this first analysis of pregnancy outcomes following CAB + RPV exposure at conception, 10 live births, including one with congenital anomaly, were reported. Plasma CAB and RPV washout concentrations during pregnancy were within the range of those in non-pregnant women. Pregnancy surveillance within ViiV Healthcare-sponsored clinical trials is ongoing, with dedicated pregnancy studies planned.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Femenino , Humanos , Embarazo , Rilpivirina , Infecciones por VIH/tratamiento farmacológico , Resultado del Embarazo , Antirretrovirales/uso terapéutico
11.
Exp Physiol ; 108(1): 12-27, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36412084

RESUMEN

NEW FINDINGS: What is the topic of this review? The emerging condition of long COVID, its epidemiology, pathophysiological impacts on patients of different backgrounds, physiological mechanisms emerging as explanations of the condition, and treatment strategies being trialled. The review leads from a Physiological Society online conference on this topic. What advances does it highlight? Progress in understanding the pathophysiology and cellular mechanisms underlying Long COVID and potential therapeutic and management strategies. ABSTRACT: Long COVID, the prolonged illness and fatigue suffered by a small proportion of those infected with SARS-CoV-2, is placing an increasing burden on individuals and society. A Physiological Society virtual meeting in February 2022 brought clinicians and researchers together to discuss the current understanding of long COVID mechanisms, risk factors and recovery. This review highlights the themes arising from that meeting. It considers the nature of long COVID, exploring its links with other post-viral illnesses such as myalgic encephalomyelitis/chronic fatigue syndrome, and highlights how long COVID research can help us better support those suffering from all post-viral syndromes. Long COVID research started particularly swiftly in populations routinely monitoring their physical performance - namely the military and elite athletes. The review highlights how the high degree of diagnosis, intervention and monitoring of success in these active populations can suggest management strategies for the wider population. We then consider how a key component of performance monitoring in active populations, cardiopulmonary exercise training, has revealed long COVID-related changes in physiology - including alterations in peripheral muscle function, ventilatory inefficiency and autonomic dysfunction. The nature and impact of dysautonomia are further discussed in relation to postural orthostatic tachycardia syndrome, fatigue and treatment strategies that aim to combat sympathetic overactivation by stimulating the vagus nerve. We then interrogate the mechanisms that underlie long COVID symptoms, with a focus on impaired oxygen delivery due to micro-clotting and disruption of cellular energy metabolism, before considering treatment strategies that indirectly or directly tackle these mechanisms. These include remote inspiratory muscle training and integrated care pathways that combine rehabilitation and drug interventions with research into long COVID healthcare access across different populations. Overall, this review showcases how physiological research reveals the changes that occur in long COVID and how different therapeutic strategies are being developed and tested to combat this condition.


Asunto(s)
Enfermedades del Sistema Nervioso Autónomo , COVID-19 , Humanos , Síndrome Post Agudo de COVID-19 , SARS-CoV-2 , Factores de Riesgo
12.
Epilepsia ; 64(11): 3099-3108, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37643892

RESUMEN

OBJECTIVE: This study was undertaken to develop a novel pathway linking genetic data with routinely collected data for people with epilepsy, and to analyze the influence of rare, deleterious genetic variants on epilepsy outcomes. METHODS: We linked whole-exome sequencing (WES) data with routinely collected primary and secondary care data and natural language processing (NLP)-derived seizure frequency information for people with epilepsy within the Secure Anonymised Information Linkage Databank. The study participants were adults who had consented to participate in the Swansea Neurology Biobank, Wales, between 2016 and 2018. DNA sequencing was carried out as part of the Epi25 collaboration. For each individual, we calculated the total number and cumulative burden of rare and predicted deleterious genetic variants and the total of rare and deleterious variants in epilepsy and drug metabolism genes. We compared these measures with the following outcomes: (1) no unscheduled hospital admissions versus unscheduled admissions for epilepsy, (2) antiseizure medication (ASM) monotherapy versus polytherapy, and (3) at least 1 year of seizure freedom versus <1 year of seizure freedom. RESULTS: We linked genetic data for 107 individuals with epilepsy (52% female) to electronic health records. Twenty-six percent had unscheduled hospital admissions, and 70% were prescribed ASM polytherapy. Seizure frequency information was linked for 100 individuals, and 10 were seizure-free. There was no significant difference between the outcome groups in terms of the exome-wide and gene-based burden of rare and deleterious genetic variants. SIGNIFICANCE: We successfully uploaded, annotated, and linked genetic sequence data and NLP-derived seizure frequency data to anonymized health care records in this proof-of-concept study. We did not detect a genetic influence on real-world epilepsy outcomes, but our study was limited by a small sample size. Future studies will require larger (WES) data to establish genetic variant contribution to epilepsy outcomes.


Asunto(s)
Epilepsia , Adulto , Humanos , Femenino , Masculino , Secuenciación del Exoma , Epilepsia/tratamiento farmacológico , Epilepsia/genética , Convulsiones/tratamiento farmacológico , Atención a la Salud , Almacenamiento y Recuperación de la Información , Anticonvulsivantes/uso terapéutico
13.
BMC Neurol ; 23(1): 58, 2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36737716

RESUMEN

BACKGROUND: Parkinson's disease (PD) is the fastest growing neurological condition worldwide. Recent theories suggest that symptoms of PD may arise due to spread of Lewy-body pathology where the process begins in the gut and propagate transynaptically via the vagus nerve to the central nervous system. In PD, gait impairments are common motor manifestations that are progressive and can appear early in the disease course. As therapies to mitigate gait impairments are limited, novel interventions targeting these and their consequences, i.e., reducing the risk of falls, are urgently needed. Non-invasive vagus nerve stimulation (nVNS) is a neuromodulation technique targeting the vagus nerve. We recently showed in a small pilot trial that a single dose of nVNS improved (decreased) discrete gait variability characteristics in those receiving active stimulation relative to those receiving sham stimulation. Further multi-dose, multi-session studies are needed to assess the safety and tolerability of the stimulation and if improvement in gait is sustained over time. DESIGN: This will be an investigator-initiated, single-site, proof-of-concept, double-blind sham-controlled randomised pilot trial in 40 people with PD. Participants will be randomly assigned on a 1:1 ratio to receive either active or sham transcutaneous cervical VNS. All participants will undergo comprehensive cognitive, autonomic and gait assessments during three sessions over 24 weeks, in addition to remote monitoring of ambulatory activity and falls, and exploratory analyses of cholinergic peripheral plasma markers. The primary outcome measure is the safety and tolerability of multi-dose nVNS in PD. Secondary outcomes include improvements in gait, cognition and autonomic function that will be summarised using descriptive statistics. DISCUSSION: This study will report on the proportion of eligible and enrolled patients, rates of eligibility and reasons for ineligibility. Adverse events will be recorded informing on the safety and device tolerability in PD. This study will additionally provide us with information for sample size calculations for future studies and evidence whether improvement in gait control is enhanced when nVNS is delivered repeatedly and sustained over time. TRIAL REGISTRATION: This trial is prospectively registered at www.isrctn.com/ISRCTN19394828 . Registered August 23, 2021.


Asunto(s)
Enfermedad de Parkinson , Estimulación del Nervio Vago , Humanos , Resultado del Tratamiento , Enfermedad de Parkinson/terapia , Estimulación del Nervio Vago/efectos adversos , Estimulación del Nervio Vago/métodos , Marcha , Progresión de la Enfermedad , Método Doble Ciego , Ensayos Clínicos Controlados Aleatorios como Asunto
14.
Brain ; 145(2): 542-554, 2022 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-34927673

RESUMEN

In this retrospective, multicentre, observational cohort study, we sought to determine the clinical, radiological, EEG, genetics and neuropathological characteristics of mitochondrial stroke-like episodes and to identify associated risk predictors. Between January 1998 and June 2018, we identified 111 patients with genetically determined mitochondrial disease who developed stroke-like episodes. Post-mortem cases of mitochondrial disease (n = 26) were identified from Newcastle Brain Tissue Resource. The primary outcome was to interrogate the clinico-radiopathological correlates and prognostic indicators of stroke-like episode in patients with mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes syndrome (MELAS). The secondary objective was to develop a multivariable prediction model to forecast stroke-like episode risk. The most common genetic cause of stroke-like episodes was the m.3243A>G variant in MT-TL1 (n = 66), followed by recessive pathogenic POLG variants (n = 22), and 11 other rarer pathogenic mitochondrial DNA variants (n = 23). The age of first stroke-like episode was available for 105 patients [mean (SD) age: 31.8 (16.1)]; a total of 35 patients (32%) presented with their first stroke-like episode ≥40 years of age. The median interval (interquartile range) between first and second stroke-like episodes was 1.33 (2.86) years; 43% of patients developed recurrent stroke-like episodes within 12 months. Clinico-radiological, electrophysiological and neuropathological findings of stroke-like episodes were consistent with the hallmarks of medically refractory epilepsy. Patients with POLG-related stroke-like episodes demonstrated more fulminant disease trajectories than cases of m.3243A>G and other mitochondrial DNA pathogenic variants, in terms of the frequency of refractory status epilepticus, rapidity of progression and overall mortality. In multivariate analysis, baseline factors of body mass index, age-adjusted blood m.3243A>G heteroplasmy, sensorineural hearing loss and serum lactate were significantly associated with risk of stroke-like episodes in patients with the m.3243A>G variant. These factors informed the development of a prediction model to assess the risk of developing stroke-like episodes that demonstrated good overall discrimination (area under the curve = 0.87, 95% CI 0.82-0.93; c-statistic = 0.89). Significant radiological and pathological features of neurodegeneration were more evident in patients harbouring pathogenic mtDNA variants compared with POLG: brain atrophy on cranial MRI (90% versus 44%, P < 0.001) and reduced mean brain weight (SD) [1044 g (148) versus 1304 g (142), P = 0.005]. Our findings highlight the often idiosyncratic clinical, radiological and EEG characteristics of mitochondrial stroke-like episodes. Early recognition of seizures and aggressive instigation of treatment may help circumvent or slow neuronal loss and abate increasing disease burden. The risk-prediction model for the m.3243A>G variant can help inform more tailored genetic counselling and prognostication in routine clinical practice.


Asunto(s)
Síndrome MELAS , Enfermedades Mitocondriales , Accidente Cerebrovascular , Adulto , ADN Mitocondrial/genética , Humanos , Síndrome MELAS/genética , Enfermedades Mitocondriales/complicaciones , Enfermedades Mitocondriales/genética , Mutación , Estudios Retrospectivos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/genética
15.
Surg Endosc ; 37(11): 8728-8734, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37563341

RESUMEN

BACKGROUND: Esophageal morphology in achalasia is thought to affect outcomes, with "end-stage" sigmoidal morphology faring poorly; however, evaluation of morphology's role in outcomes has been limited by lack of objective characterization. Hence, the goals of this study were twofold: characterize the variability of timed barium esophagram (TBE) interpretation and evaluate an objective classification of TBE tortuosity: length-to-height ratio (LHR). We hypothesized that the esophagus must elongate to become sigmoidal such that sigmoidal morphology would demonstrate a larger LHR. METHODS: Ninety pre-operative TBEs were selected from an institutional database. Esophageal morphology was categorized as straight, intermediate, or sigmoidal. Esophageal length was measured by a mid-lumen line from the aortic knob to the esophagogastric junction on TBE; height was measured vertically from the aortic knob to the level of the esophagogastric junction. The length divided by the height generated the LHR. Descriptive statistics and frequency of expert agreement were calculated. Median LHR was compared between consensus morphologies. A receiver operating characteristic (ROC) determined the optimal LHR for sigmoidal vs non-sigmoidal characterization. RESULTS: From a total of 90 pre-operative TBEs, expert consensus morphology was reached in 56 (62.2%) cases. Pairs of experts agreed on morphology in 62-74% of TBEs, with all three experts agreeing on 46.7-48.9% of cases. Median LHR between expert consensus morphologies was 1.03, 1.09, and 1.24 for straight, intermediate, and sigmoidal morphologies, respectively (p < 0.001). ROC demonstrated that an LHR cutoff of 1.13 was 100% sensitive and 95% specific (AUC 0.99) for ruling out sigmoidal morphology. CONCLUSION: These findings confirm our anecdotal experience that subjective morphology interpretation is variable, even between experts at a high-volume center. LHR provides an objective method for classification, allowing us to overcome the limitations of inter-observer variability, thus paving the way for future study of the role of morphology in achalasia outcomes.


Asunto(s)
Acalasia del Esófago , Humanos , Acalasia del Esófago/diagnóstico por imagen , Acalasia del Esófago/cirugía , Sulfato de Bario , Manometría/métodos , Unión Esofagogástrica
16.
Can J Neurol Sci ; 50(4): 579-583, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-35684949

RESUMEN

BACKGROUND: Sensory-motor decoupling at the cortical level involving cholinergic circuitry has also been reported in Parkinson's Disease (PD). Short-latency afferent inhibition (SAI) is a transcranial magnetic stimulation (TMS) paradigm that has been used previously to probe cortical cholinergic circuits in well-characterised subgroups of patients with PD. In the current study, we compared SAI in a cohort of PD patients at various stages of disease and explored correlations between SAI and various clinical measures of disease severity. METHODS: The modified Hoehn and Yahr (H&Y) scale was used to stage disease in 22 patients with PD. Motor and cognitive function were assessed using the MDS-UPDRS (Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale) part III and MoCA (Montreal Cognitive Assessment) score, respectively. Objective gait assessment was performed using an electronic walkway (GAITRite®). SAI was measured as the average percentage inhibition of test motor-evoked potentials (MEPs) conditioned by electrical stimulation of the contralateral median nerve at the wrist. RESULTS: SAI was significantly reduced in patients with advanced PD (H&Y stage 3) compared to early PD patients (H&Y stage 1) on pairwise comparison. The visuospatial executive function and orientation domains of cognition demonstrated significant negative associations with SAI. CONCLUSION: Cortical sensory-motor integration is progressively diminished as disease progresses. The observation that a reduction in SAI is associated with a reduction in cognitive function possibly reflects the progressive involvement of cortical cholinergic circuits in PD with increasing motor stage. Future longitudinal studies are necessary to confirm this preliminary result.


Asunto(s)
Inhibición Neural , Enfermedad de Parkinson , Humanos , Inhibición Neural/fisiología , Potenciales Evocados Motores/fisiología , Muñeca , Colinérgicos
17.
Vascular ; : 17085381231214318, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38031998

RESUMEN

INTRODUCTION: Aortic graft infection (AGI) is a rare complication following endovascular aneurysm repair and is associated with substantial morbidity and mortality. The traditional management of AGI is intravenous antibiotic therapy and surgical explantation. In this case series, percutaneous drainage was used as a bridge therapy in the treatment of AGI. METHODS: We report two cases, 78-year-old male and 57-year-old female, in whom image-guided percutaneous drainage was used to treat AGI in two contrasting contexts. Informed consent was obtained from both cases/relatives for publication. RESULTS: Both cases underwent successful percutaneous drainage of AGI utilized as a bridge therapy before definitive surgical reconstruction and graft explantation. Each patient had a different outcome. In the first case, the patient's comorbidities and severe disease state could not be overcome, resulting in his death. The second patient benefitted from the percutaneous drainage by allowing her more time ameliorate her malnutrition before definitive surgery. CONCLUSION: Data on the outcomes of percutaneous drainage of AGI is limited. The successful procedure described in this case series emphasizes the need to conduct more research to evaluate the safety and efficacy of this treatment approach before the surgical explantation.

18.
Neuromodulation ; 26(3): 681-689, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37032583

RESUMEN

OBJECTIVES: Fatigue is one of the most important symptoms needing improvement in Primary Sjögren's syndrome (PSS). Previous data from our group suggest that noninvasive stimulation of the vagus nerve (nVNS) may improve symptoms of fatigue. This experimental medicine study uses the gammaCore device (electroCore) and a sham device to investigate the relationship between nVNS and fatigue in PSS, and to explore potential mechanisms involved. MATERIALS AND METHODS: Forty participants with PSS were randomly assigned to use active (n = 20) or sham (n = 20) nVNS devices twice daily for 54 days in a double-blind manner. Patient-reported measures of fatigue were collected at baseline and day 56: Profile of Fatigue (PRO-F)-Physical, PRO-F-Mental and Visual Analogue Scale of abnormal fatigue (fVAS). Neurocognitive tests, immunologic responses, electroencephalography alpha reactivity, muscle acidosis, and heart rate variability were compared between devices from baseline to day 56 using analysis of covariance. RESULTS: PRO-F-Physical, PRO-F-Mental, and fVAS scores were significantly reduced at day 56 in the active group only (p = 0.02, 0.02, and 0.04, respectively). Muscle bioenergetics and heart rate variability showed no change between arms. There were significant improvements in digit span and a neurocognitive test (p = 0.03), and upon acute nVNS stimulation, frontal region alpha reactivity showed a significant negative relationship with fatigue scores in the active group (p < 0.01). CONCLUSIONS: We observed significant improvements in three measures of fatigue at day 56 with the active device but not the sham device. Directly after device use, fatigue levels correlate with measures of alpha reactivity, suggesting modulation of cholinergic system integrity as a mechanism of action for nVNS.


Asunto(s)
Fatiga , Síndrome de Sjögren , Estimulación del Nervio Vago , Humanos , Fatiga/diagnóstico , Fatiga/etiología , Fatiga/terapia , Dimensión del Dolor , Síndrome de Sjögren/complicaciones , Síndrome de Sjögren/terapia , Resultado del Tratamiento , Estimulación del Nervio Vago/métodos
19.
Int J Mol Sci ; 24(2)2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36675126

RESUMEN

Glioblastoma multiforme (GBM) is the most lethal adult brain cancer. Temozolomide (TMZ), the standard chemotherapeutic drug used in GBM, has limited benefit and alternate therapies are needed to improve GBM treatment. Nerve growth factor (NGF) and its precursor proNGF are increasingly recognized as stimulators of human tumor progression. The expression and stimulatory effect of NGF on GBM cell growth has previously been reported, but the status of proNGF in GBM is unreported. In this study, we have investigated proNGF expression and biological activity in GBM. A clinical cohort of GBM (n = 72) and low-grade glioma (n = 20) was analyzed by immunohistochemistry for proNGF and digital quantification. ProNGF expression was significantly increased in GBM compared to low grade gliomas and proNGF was also detected in patient plasma samples. ProNGF was also detected in most GBM cell lines by Western blotting. Although anti-proNGF blocking antibodies inhibited cell growth in GBM cells with methylated MGMT gene promoter, targeting proNGF could not potentiate the efficacy of TMZ. In subcutaneous xenograft of human GBM cells, anti-proNGF antibodies slightly reduced tumor volume but had no impact on TMZ efficacy. In conclusion, this data reveals that proNGF is overexpressed in GBM and can stimulate cancer cell growth. The potential of proNGF as a clinical biomarker and therapeutic target warrants further investigations.


Asunto(s)
Antineoplásicos Alquilantes , Neoplasias Encefálicas , Glioblastoma , Glioma , Temozolomida , Humanos , Antineoplásicos Alquilantes/farmacología , Antineoplásicos Alquilantes/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Glioblastoma/patología , Glioma/tratamiento farmacológico , Glioma/genética , Glioma/metabolismo , Temozolomida/farmacología , Temozolomida/uso terapéutico
20.
Br J Nurs ; 32(5): 260-265, 2023 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-36913333

RESUMEN

The COVID-19 pandemic restricted face-to-face contact between students and educators, limiting continual assessment of student's clinical skill development. This led to rapid transformational online adaptations to nursing education. This article will present and discuss the introduction of a clinical 'viva voce' approach, which has been used at one university to formatively assess students' clinical learning and reasoning skills using virtual methods. The Virtual Clinical Competency Conversation (V3C) was developed using the 'Think aloud approach' and involved facilitated one-to-one discussion based on two questions from a bank of 17 predefined clinically focused questions. A total of 81 pre-registration students completed the formative assessment process. Overall, feedback from students and academic facilitators was positive and facilitated both learning and consolidation in a safe and nurturing way. Further local evaluation is continuing to measure the impact of the V3C approach on student learning now that some aspects of face-to-face education have resumed.


Asunto(s)
COVID-19 , Educación en Enfermería , Estudiantes de Enfermería , Humanos , Pandemias , COVID-19/epidemiología , Aprendizaje , Competencia Clínica
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