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1.
Gastrointest Endosc ; 99(1): 104-107, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37722511

RESUMEN

BACKGROUND AND AIMS: Coaxial double-pigtail plastic stent (DPPS) placement is often performed within lumen-apposing metal stents (LAMSs) for drainage of pancreatic fluid collections (PFCs) to prevent adverse events (AEs) such as stent occlusion and bleeding. This study compares the safety and outcomes of LAMSs alone versus LAMSs with coaxial DPPSs for PFC management. METHODS: Patients undergoing drainage of a PFC with LAMSs were retrospectively identified and categorized as LAMS or LAMS/DPPS based on initial drainage strategy. The AE rate, AE type, and clinical success were extracted by chart review. RESULTS: One hundred eighty-five individuals (83 LAMS, 102 LAMS/DPPS) were identified. No significant differences were found in rates of clinical success (75.9% LAMS vs 69.6% LAMS/DDPS, P = .34) or overall AEs (15.7% LAMS vs 15.7% LAMS/DPPS, P = .825). CONCLUSIONS: In this comparative single-center study, placement of a coaxial DPPS for drainage of PFCs with LAMSs did not affect rates of AEs or clinical success.


Asunto(s)
Enfermedades Pancreáticas , Humanos , Estudios Retrospectivos , Enfermedades Pancreáticas/cirugía , Enfermedades Pancreáticas/etiología , Stents/efectos adversos , Drenaje/efectos adversos , Hemorragia/etiología
2.
Dig Dis Sci ; 68(9): 3573-3583, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37432533

RESUMEN

BACKGROUND: The eosinophilic esophagitis histologic scoring system (EoEHSS) was developed to enhance the diagnostic standard of peak eosinophil count (PEC) in evaluating disease activity in EoE. AIMS: (1) Correlate the EoEHSS and PEC to measures of symptomatic and endoscopic disease activity, (2) Correlate EoEHSS grade and stage subcomponents to clinical, radiology, and endoscopic markers of fibrotic disease, (3) Evaluate EoEHSS remission in asymptomatic patients with PEC < 15 eosinophils per high powered field (eos/hpf). METHODS: Secondary analysis of prospective cohort data of 22 patients with EoE that underwent dietary therapy and endoscopy at 3 time points. Active disease was defined by EoEHSS grade or stage > 0.125, symptomatic disease by EoE symptom activity index > 20, endoscopic disease by endoscopic reference score > 2, and histologic disease by PEC ≥ 15 eos/hpf. EoEHSS remission was defined by esophageal inflammation (EI) grade of 0-1, EI stage of 0, total grade ≤ 3, and total stage ≤ 3. RESULTS: EoEHSS grade and stage did not correlate with symptomatic disease but did with endoscopic and histologic disease. PEC showed similar correlation pattern. Abnormal grade and stage had strong sensitivity (87-100%) but poor specificity (11-36%) to detect symptomatic, endoscopic, and histologic disease activity. Lamina propria fibrosis was evaluated in 36% of biopsies and did not correlate with minimum esophageal diameter. Out of 14 patients who were in complete symptomatic, endoscopic, and histologic remission, 8 met criteria for EoEHSS remission. CONCLUSION: The positive and negative correlations of EoEHSS to specific measures of symptomatic, histologic, and endoscopic activity suggest that it provides complementary information in EoE.


Asunto(s)
Esofagitis Eosinofílica , Humanos , Esofagitis Eosinofílica/diagnóstico , Esofagitis Eosinofílica/terapia , Esofagitis Eosinofílica/patología , Estudios Prospectivos , Eosinófilos/patología , Inflamación/patología , Endoscopía Gastrointestinal
4.
Mar Drugs ; 20(10)2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-36286458

RESUMEN

Harmful algal blooms are an increasing worldwide threat to the seafood industry and human health as a consequence of the natural production of biotoxins that can accumulate in shellfish. In the Argentine Sea, this has been identified as an issue for the offshore fisheries of Patagonian scallops (Zygochlamys patagonica), leading to potentially harmful effects on consumers. Here we assess spatial and temporal patterns in marine biotoxin concentrations in Patagonian scallops harvested in Argentinian waters between 2012-2017, based on analyses for paralytic shellfish toxins, lipophilic toxins, and amnesic shellfish toxins. There was no evidence for concentrations of lipophilic or amnesic toxins above regulatory acceptance thresholds, with trace concentrations of pectenotoxin 2, azaspiracid 2 and okadaic acid group toxins confirmed. Conversely, paralytic shellfish toxins were quantified in some scallops. Gonyautoxins 1 and 2 dominated the unusual toxin profiles (91%) in terms of saxitoxin equivalents with maximum concentrations reaching 3985 µg STX eq/kg and with changes in profiles linked in part to seasonal changes. Total toxin concentrations were compared between samples of the adductor muscle and whole tissue, with results showing the absence of toxins in the adductor muscle confirming toxin accumulation in the digestive tracts of the scallops and the absence of a human health threat following the processing of scallop adductor meat. These findings highlight that paralytic shellfish toxins with an unusual toxin profile can occur in relatively high concentrations in whole Patagonian scallops in specific regions and during particular time periods, also showing that the processing of scallops on board factory ships to obtain frozen adductor muscle is an effective management process that minimizes the risk of poisonings from final products destined for human consumption.


Asunto(s)
Toxinas Marinas , Pectinidae , Animales , Humanos , Toxinas Marinas/análisis , Ácido Ocadaico/análisis , Saxitoxina/análisis , Alimentos Marinos/análisis
5.
Am J Public Health ; 112(8): 1212-1216, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35830662

RESUMEN

Xylazine is a nonopioid veterinary anesthetic and sedative that is increasingly detected in the illicit drug supply in the United States. Data indicate a striking prevalence of xylazine among opioid-involved overdose deaths. The emergence of xylazine in the illicit drug supply poses many unknowns and potential risks for people who use drugs. The public health system needs to respond by increasing testing to determine the prevalence of xylazine, identifying its potential toxicity at various exposure levels, and taking mitigating action to prevent harms. Currently, there is little testing capable of identifying xylazine in drug supplies, which limits the possibility of public health intervention, implementation of harm reduction strategies, or development of novel treatment strategies. (Am J Public Health. 2022;112(8):1212-1216. https://doi.org/10.2105/AJPH.2022.306881).


Asunto(s)
Sobredosis de Droga , Drogas Ilícitas , Sobredosis de Opiáceos , Analgésicos Opioides/toxicidad , Sobredosis de Droga/epidemiología , Sobredosis de Droga/prevención & control , Reducción del Daño , Humanos , Salud Pública , Estados Unidos/epidemiología , Xilazina
6.
Antioxid Redox Signal ; 36(4-6): 337-353, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34514838

RESUMEN

Significance: Reactive sulfur and nitrogen species such as hydrogen sulfide (H2S) and nitric oxide (NO•) are ubiquitous cellular signaling molecules that play central roles in physiology and pathophysiology. A deeper understanding of these signaling pathways will offer new opportunities for therapeutic treatments and disease management. Recent Advances: Chemiluminescence methods have been fundamental in detecting and measuring biological reactive sulfur and nitrogen species, and new approaches are emerging for imaging these analytes in living intact specimens. Ozone-based and luminol-based chemiluminescence methods have been optimized for quantitative analysis of hydrogen sulfide and nitric oxide in biological samples and tissue homogenates, and caged luciferin and 1,2-dioxetanes are emerging as a versatile approach for monitoring and imaging reactive sulfur and nitrogen species in living cells and animal models. Critical Issues: This review article will cover the major chemiluminescence approaches for detecting, measuring, and imaging reactive sulfur and nitrogen species in biological systems, including a brief history of the development of the most established approaches and highlights of the opportunities provided by emerging approaches. Future Directions: Emerging chemiluminescence approaches offer new opportunities for monitoring and imaging reactive sulfur and nitrogen species in living cells, animals, and human clinical samples. Widespread adoption and translation of these approaches, however, requires an emphasis on rigorous quantitative methods, reproducibility, and effective technology transfer. Antioxid. Redox Signal. 36, 337-353.


Asunto(s)
Sulfuro de Hidrógeno , Nitrógeno , Animales , Sulfuro de Hidrógeno/metabolismo , Mediciones Luminiscentes , Especies de Nitrógeno Reactivo/metabolismo , Reproducibilidad de los Resultados , Azufre/metabolismo
7.
J Addict Dis ; 40(1): 92-95, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34121634

RESUMEN

BACKGROUND: While Opioid use disorder (OUD)-related mortality is epidemic in the United States, regions like Appalachia are disproportionately affected. Moreover, a dual epidemic of Hepatitis C virus (HCV) infections and OUD-related admissions has been observed. OBJECTIVE: To evaluate sociodemographic characteristics of opioid-dependent patients admitted for medically managed withdrawal in East Tennessee and compare those with and without HCV. METHODS: Cross-sectional study of patients with an OUD admitted for treatment, comparing those with and without a history of HCV. RESULTS: The studied population was found to have high rates of HCV (36%), intravenous drug use (IVDU) (77%), polysubstance use (84%), previous incarceration (87%), and unemployment (80%). Patients with HCV, compared to those without, were significantly more likely to have a history of IVDU, IVDU complications, and polysubstance use. CONCLUSIONS: This sample reflects the significant morbidity of OUD in East Tennessee. To prevent mortality, contributing factors such as polysubstance use and OUD treatment during incarceration need to be specifically addressed.


Asunto(s)
Hepatitis C , Trastornos Relacionados con Opioides , Abuso de Sustancias por Vía Intravenosa , Síndrome de Abstinencia a Sustancias , Analgésicos Opioides/uso terapéutico , Estudios Transversales , Hepacivirus , Hepatitis C/tratamiento farmacológico , Hepatitis C/epidemiología , Humanos , Trastornos Relacionados con Opioides/tratamiento farmacológico , Trastornos Relacionados con Opioides/epidemiología , Abuso de Sustancias por Vía Intravenosa/tratamiento farmacológico , Abuso de Sustancias por Vía Intravenosa/epidemiología , Síndrome de Abstinencia a Sustancias/tratamiento farmacológico , Tennessee/epidemiología , Estados Unidos
8.
Med Clin North Am ; 106(1): 43-60, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34823734

RESUMEN

In the United States, alcohol is the most common substance used and the spectrum of unhealthy alcohol use is highly prevalent. Complications of unhealthy alcohol use affect nearly every organ system. One of the most frequent and potentially life-threatening of these complications is alcohol withdrawal syndrome for which benzodiazepines remain first-line therapy. Pharmacologic treatment of alcohol use disorder, the most severe form of unhealthy alcohol use, is underutilized despite the availability of multiple effective medications. Although behavioral therapies are an important component of treatment, they are overemphasized at the expense of pharmacotherapy.


Asunto(s)
Alcoholismo/diagnóstico , Alcoholismo/terapia , Benzodiazepinas/uso terapéutico , Terapia Cognitivo-Conductual/métodos , Síndrome de Abstinencia a Sustancias/tratamiento farmacológico , Anciano , Síndrome Alcohólico de Korsakoff/diagnóstico , Síndrome Alcohólico de Korsakoff/epidemiología , Alcoholismo/complicaciones , Alcoholismo/epidemiología , Biomarcadores/sangre , Nivel de Alcohol en Sangre , Quimioterapia/economía , Femenino , Humanos , Hepatopatías Alcohólicas/diagnóstico , Hepatopatías Alcohólicas/epidemiología , Masculino , Síndrome de Abstinencia a Sustancias/etiología , Estados Unidos
9.
Mar Drugs ; 19(12)2021 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-34940694

RESUMEN

Saxitoxins (STXs) are a family of potent neurotoxins produced naturally by certain species of phytoplankton and cyanobacteria which are extremely toxic to mammalian nervous systems. The accumulation of STXs in bivalve molluscs can significantly impact animal and human health. Recent work conducted in the North Sea highlighted the widespread presence of various saxitoxins in a range of benthic organisms, with the common sunstar (Crossaster papposus) demonstrating high concentrations of saxitoxins. In this study, an extensive sampling program was undertaken across multiple seas surrounding the UK, with 146 starfish and 5 brittlestars of multiple species analysed for STXs. All the common sunstars analysed (n > 70) contained quantifiable levels of STXs, with the total concentrations ranging from 99 to 11,245 µg STX eq/kg. The common sunstars were statistically different in terms of toxin loading to all the other starfish species tested. Two distinct toxic profiles were observed in sunstars, a decarbomylsaxitoxin (dcSTX)-dominant profile which encompassed samples from most of the UK coast and an STX and gonyautoxin2 (GTX2) profile from the North Yorkshire coast of England. Compartmentalisation studies demonstrated that the female gonads exhibited the highest toxin concentrations of all the individual organs tested, with concentrations >40,000 µg STX eq/kg in one sample. All the sunstars, male or female, exhibited the presence of STXs in the skin, digestive glands and gonads. This study highlights that the common sunstar ubiquitously contains STXs, independent of the geographical location around the UK and often at concentrations many times higher than the current regulatory limits for STXs in molluscs; therefore, the common sunstar should be considered toxic hereafter.


Asunto(s)
Toxinas Marinas/análisis , Neurotoxinas/análisis , Saxitoxina/análisis , Estrellas de Mar , Animales , Organismos Acuáticos , Intoxicación por Mariscos
10.
Proc Natl Acad Sci U S A ; 118(44)2021 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-34654739

RESUMEN

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in over 100 million infections and millions of deaths. Effective vaccines remain the best hope of curtailing SARS-CoV-2 transmission, morbidity, and mortality. The vaccines in current use require cold storage and sophisticated manufacturing capacity, which complicates their distribution, especially in less developed countries. We report the development of a candidate SARS-CoV-2 vaccine that is purely protein based and directly targets antigen-presenting cells. It consists of the SARS-CoV-2 Spike receptor-binding domain (SpikeRBD) fused to an alpaca-derived nanobody that recognizes class II major histocompatibility complex antigens (VHHMHCII). This vaccine elicits robust humoral and cellular immunity against SARS-CoV-2 and its variants. Both young and aged mice immunized with two doses of VHHMHCII-SpikeRBD elicit high-titer binding and neutralizing antibodies. Immunization also induces strong cellular immunity, including a robust CD8 T cell response. VHHMHCII-SpikeRBD is stable for at least 7 d at room temperature and can be lyophilized without loss of efficacy.


Asunto(s)
Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/farmacología , COVID-19/inmunología , COVID-19/prevención & control , Pandemias , SARS-CoV-2/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Neutralizantes/biosíntesis , Anticuerpos Antivirales/biosíntesis , Células Presentadoras de Antígenos/inmunología , Linfocitos T CD8-positivos/inmunología , COVID-19/epidemiología , Vacunas contra la COVID-19/administración & dosificación , Camélidos del Nuevo Mundo/inmunología , Femenino , Antígenos de Histocompatibilidad Clase II/inmunología , Humanos , Inmunidad Celular , Inmunidad Humoral , Inmunización Secundaria , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Transgénicos , Pandemias/prevención & control , Proteínas Recombinantes de Fusión/administración & dosificación , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , SARS-CoV-2/genética , Anticuerpos de Dominio Único/administración & dosificación , Anticuerpos de Dominio Único/inmunología , Glicoproteína de la Espiga del Coronavirus/administración & dosificación , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología
11.
Cell Rep ; 36(5): 109483, 2021 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-34348157

RESUMEN

Loss-of-function variants in the gene SCN2A, which encodes the sodium channel NaV1.2, are strongly associated with autism spectrum disorder and intellectual disability. An estimated 20%-30% of children with these variants also suffer from epilepsy, with altered neuronal activity originating in neocortex, a region where NaV1.2 channels are expressed predominantly in excitatory pyramidal cells. This is paradoxical, as sodium channel loss in excitatory cells would be expected to dampen neocortical activity rather than promote seizure. Here, we examined pyramidal neurons lacking NaV1.2 channels and found that they were intrinsically hyperexcitable, firing high-frequency bursts of action potentials (APs) despite decrements in AP size and speed. Compartmental modeling and dynamic-clamp recordings revealed that NaV1.2 loss prevented potassium channels from properly repolarizing neurons between APs, increasing overall excitability by allowing neurons to reach threshold for subsequent APs more rapidly. This cell-intrinsic mechanism may, therefore, account for why SCN2A loss-of-function can paradoxically promote seizure.


Asunto(s)
Canal de Sodio Activado por Voltaje NAV1.2/metabolismo , Neocórtex/citología , Células Piramidales/metabolismo , Potenciales de Acción , Animales , Dendritas/metabolismo , Eliminación de Gen , Ratones Endogámicos C57BL , Ratones Noqueados
12.
J Shoulder Elbow Surg ; 30(7S): S27-S37, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33892117

RESUMEN

BACKGROUND: Commercially available suture anchors for rotator cuff repairs can differ significantly in architecture and material. Clinical data on their osseous integration and its effect on patient-reported outcomes is scarce. Preclinical investigations indicated a higher rate of osseous integration for the open-architecture design of the Healicoil Regenesorb anchor than the closed-threaded design of the Twinfix (Smith & Nephew). The purpose of this study was to investigate these 2 anchors with different architecture and material to determine their effect on osseous integration and clinical outcomes after rotator cuff repair. METHODS: A prospective randomized controlled trial was performed from 2014 to 2019. Sixty-four patients (39 females, 25 males) with an average age of 58.7 years who underwent arthroscopic rotator cuff repair by one of 4 board-certified, fellowship-trained surgeons were randomized to receive Healicoil Regenesorb (PLGA/ß-TCP/Calcium Sulfate) or Twinfix Ultra HA (PLLA/HA) anchors. Thirty-two patients had Healicoil anchors implanted, and 32 patients had Twinfix anchors implanted. Of the 64 patients, 51 returned at 24 months for computed tomographic (CT) examination (25 Twinfix and 26 Healicoil) to determine osteointegration of the anchors. Patient-reported outcomes, including Penn Shoulder Score (PENN), Western Ontario Rotator Cuff Index, visual analog scale, EQ-5D, Single Assessment Numeric Evaluation, Global Rating of Change, were collected at baseline, 6 weeks, 3 months, 6 months, 12 months, and 24 months. Ultrasonography was used to assess rotator cuff integrity after 6 months. Two board-certified, fellowship-trained orthopedic surgeons, blinded to the type of anchors, analyzed the CT scans to assess the anchor osteointegration at 24 months using a previously published grading scale. RESULTS: There were no differences in demographics, preoperative outcomes, or baseline characteristics such as tear size, number of anchors, Goutallier classification, or smoking status between groups. There was no difference in osseous integration between the 2 anchors at 24 months (P = .117). Eight patients had rotator cuff retears, of which 2 patients had Twinfix anchors and 6 patients had Healicoil anchors (P = .18). There were no statistically significant differences in patient-reported outcomes or complications between groups. The 2-year PENN scores were 89 with the Twinfix and 88 with Healicoil anchors (P = .55). CONCLUSION: Despite differences in material and anchor architecture, the rate of healing and patient-reported outcomes were similar between the Twinfix and Healicoil anchor groups. The rate of osteointegration was the same at 2 years.


Asunto(s)
Lesiones del Manguito de los Rotadores , Manguito de los Rotadores , Artroscopía , Durapatita , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ontario , Poliésteres , Estudios Prospectivos , Manguito de los Rotadores/diagnóstico por imagen , Manguito de los Rotadores/cirugía , Lesiones del Manguito de los Rotadores/diagnóstico por imagen , Lesiones del Manguito de los Rotadores/cirugía , Anclas para Sutura
13.
Adolesc Res Rev ; 6(2): 91-123, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33553578

RESUMEN

Understanding how child and adolescent health is influenced by fluctuations in socioeconomic status has important public health and policy implications, as children are often subjected to both micro and macro-level socioeconomic events. This study provides the first systematic review to date on the relationship between changes in household or parental socioeconomic status and subsequent child and adolescent health outcomes. Eighty articles were identified for inclusion in this review, examining 85 different socioeconomic exposures in five categories: Income (n = 64), Employment (n = 14), Socioeconomic Mobility (n = 3), Education (n = 2), and Food Insecurity (n = 2). The health outcomes analyzed by these eighty articles were separated into eight discrete categories, with many articles examining outcomes in more than one category: Anthropometric Measurements (n = 21), Cognition and Development (n = 15), Dental Health (n = 3), Health Behaviours (n = 9), Mental Health (n = 12), Overall Parent/Guardian Assessed health (n = 6); Physical Health Outcomes (n = 11), and Socio-Emotional Behaviour (n = 30). Several consistent patterns emerged in the literature, such as a link between increased income and improved, or decreased income and deteriorating, cognition, dental health, and physical health. The results of this review suggest a need to replicate current studies in diverse geographies to expand generalizability and clarify regional patterns. There should also be an effort to go beyond income, and employment, to assess the relationship between less frequently studied socioeconomic exposures and child health outcomes. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40894-021-00151-8.

14.
JSES Int ; 5(1): 109-113, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33554175

RESUMEN

BACKGROUND: Previous studies show that reverse shoulder arthroplasty (RSA) may improve forward elevation (FE) but external rotation may remain impaired with substantial teres minor fatty infiltration. The purpose of this study was to examine the influence of fatty infiltration on postoperative range of motion (ROM) and patient-reported outcomes (PROs) after RSA with a more lateralized center of rotation. METHODS: About 69 patients (average age 69 years; 44 women, 25 men) with preoperative MRI, 1-year postoperative ROM, 2-year Veteran's Rand Survey, American Shoulder and Elbow Surgeons subjective form, and Single Alpha-Numeric Evaluation scores who underwent RSA with a lateralized glenoid component between 2010 and 2014 were identified. Patients with Fuchs stage 3 fatty degeneration were compared with patients with Fuchs stage ≤ 2 using a one-way ANOVA. RESULTS: Eleven patients had Fuchs stage 3 in the teres minor and 28 with stage 3 in the infraspinatus. Charlson comorbidity indices, Veteran's Rand Survey scores, age, and BMI were not different between groups. There were no differences after one year (follow-up = 15 ± 14 months) in FE (FE = 128 ± 29) or external rotation (33 ± 13) between groups. There were no differences in two-year minimum (follow-up = 42.9 ± 17.9 months) American Shoulder and Elbow Surgeons scores between degenerated teres minor (76.4 ± 20) or infraspinatus (69.1 ± 24) groups. CONCLUSION: This is the first study to assess the influence of teres minor and infraspinatus fatty infiltration on the postoperative ROM and PROs with a more lateralized glenoid RSA implant. Our results show that in a more lateralized RSA, neither teres minor nor infraspinatus fatty infiltration appear to negatively influence ROM or PROs.

15.
J Physiol ; 599(2): 647-665, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33146903

RESUMEN

KEY POINTS: We show that NMDA receptors (NMDARs) elicit a long-term increase in the firing rates of inhibitory stellate cells of the cerebellum NMDARs induce intrinsic plasticity through a Ca2+ - and CaMKII-dependent pathway that drives shifts in the activation and inactivation properties of voltage-gated Na+ (Nav ) channels An identical Ca2+ - and CaMKII-dependent signalling pathway is triggered during whole-cell recording which lowers the action potential threshold by causing a hyperpolarizing shift in the gating properties of Nav channels. Our findings open the more general possibility that NMDAR-mediated intrinsic plasticity found in other cerebellar neurons may involve similar shifts in Nav channel gating. ABSTRACT: Memory storage in the mammalian brain is mediated not only by long-lasting changes in the efficacy of neurotransmitter receptors but also by long-term modifications to the activity of voltage-gated ion channels. Activity-dependent plasticity of voltage-gated ion channels, or intrinsic plasticity, is found throughout the brain in virtually all neuronal types, including principal cells and interneurons. Although intrinsic plasticity has been identified in neurons of the cerebellum, it has yet to be studied in inhibitory cerebellar stellate cells of the molecular layer which regulate activity outflow from the cerebellar cortex by feedforward inhibition onto Purkinje cells. The study of intrinsic plasticity in stellate cells has been particularly challenging as membrane patch breakthrough in electrophysiology experiments unintentionally triggers changes in spontaneous firing rates. Using cell-attached patch recordings to avoid disruption, we show that activation of extrasynaptic N-methyl-d-aspartate receptors (NMDARs) elicits a long-term increase in the firing properties of stellate cells by stimulating a rise in cytosolic Ca2+ and activation of Ca²âº/calmodulin-dependent protein kinase II (CaMKII). An identical signalling pathway is triggered during whole-cell recording which lowers the action potential threshold by causing a hyperpolarizing shift in the gating properties of voltage-gated sodium (Nav ) channels. Together, our findings identify an unappreciated role of Nav channel-dependent intrinsic plasticity in cerebellar stellate cells which, in concert with non-canonical NMDAR signalling, provides the cerebellum with an unconventional mechanism to fine-tune motor behaviour.


Asunto(s)
Cerebelo , Receptores de N-Metil-D-Aspartato , Potenciales de Acción , Animales , Cerebelo/metabolismo , Técnicas de Placa-Clamp , Receptores de N-Metil-D-Aspartato/metabolismo , Sodio
16.
Dig Dis Sci ; 66(9): 3096-3104, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-32995996

RESUMEN

BACKGROUND: Identification of clinical predictors of response to first-line therapies for EoE is needed to guide initial medical management. STUDY DESIGN: A retrospective analysis of patients diagnosed with EoE from 2011 to 2018 was conducted. Clinical and diagnostic variables including demographics, endoscopic, and esophagram findings were compared between PPI responders and PPI nonresponders. All patients underwent a standard 8-week twice-daily PPI trial, with PPI responsiveness defined as < 15 eos/hpf on repeat EGD. Univariate and multivariable analyses were conducted to identify risk factors for nonresponse, and ROC curves were created to identify cutoff values. RESULTS: A total of 223 EoE patients (135 male, median age 39 (29-51)) were identified, with PPI nonresponse (PPI-NR) in 71% of patients. PPI-NR was seen in all 10 patients with failure of scope passage, with an OR of 9.06 by univariate analysis (P = 0.1485). In a multivariable model, age per 10 years (OR 0.71; P = 0.007), BMI per 1 kg/m2 (OR 0.94; P = 0.03), and peripheral eosinophil count per 100 per mm3 (OR 1.37; P = 0.003) were independent risk factors. Dichotomization to maximize sensitivity and specificity identified age ≤ 36 years old, BMI ≤ 25.2 kg/m2, and peripheral eos > 460 per mm3 as predictive thresholds for PPI-NR. The probability of PPI-NR was 72.4-84.5% with 1 risk factor, 87.9-93.8% with 2 risk factors, and 97.2% with all 3 risk factors. CONCLUSIONS: Young age, reduced BMI, elevated peripheral eosinophil count, and likely inability to pass an endoscope predict lack of response to PPIs in patients with EoE.


Asunto(s)
Resistencia a Medicamentos , Endoscopía/métodos , Esofagitis Eosinofílica , Eosinófilos , Esófago , Inhibidores de la Bomba de Protones , Adulto , Biopsia/métodos , Índice de Masa Corporal , Monitoreo de Drogas/métodos , Esofagitis Eosinofílica/sangre , Esofagitis Eosinofílica/diagnóstico , Esofagitis Eosinofílica/tratamiento farmacológico , Esofagitis Eosinofílica/epidemiología , Esófago/diagnóstico por imagen , Esófago/patología , Femenino , Humanos , Recuento de Leucocitos/métodos , Masculino , Valor Predictivo de las Pruebas , Pronóstico , Inhibidores de la Bomba de Protones/administración & dosificación , Inhibidores de la Bomba de Protones/efectos adversos , Estudios Retrospectivos , Sensibilidad y Especificidad , Estados Unidos/epidemiología
17.
PLoS Comput Biol ; 16(12): e1008463, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33315892

RESUMEN

Cerebellar stellate cells (CSCs) are spontaneously active, tonically firing (5-30 Hz), inhibitory interneurons that synapse onto Purkinje cells. We previously analyzed the excitability properties of CSCs, focusing on four key features: type I excitability, non-monotonic first-spike latency, switching in responsiveness and runup (i.e., temporal increase in excitability during whole-cell configuration). In this study, we extend this analysis by using whole-cell configuration to show that these neurons can also burst when treated with certain pharmacological agents separately or jointly. Indeed, treatment with 4-Aminopyridine (4-AP), a partial blocker of delayed rectifier and A-type K+ channels, at low doses induces a bursting profile in CSCs significantly different than that produced at high doses or when it is applied at low doses but with cadmium (Cd2+), a blocker of high voltage-activated (HVA) Ca2+ channels. By expanding a previously revised Hodgkin-Huxley type model, through the inclusion of Ca2+-activated K+ (K(Ca)) and HVA currents, we explain how these bursts are generated and what their underlying dynamics are. Specifically, we demonstrate that the expanded model preserves the four excitability features of CSCs, as well as captures their bursting patterns induced by 4-AP and Cd2+. Model investigation reveals that 4-AP is potentiating HVA, inducing square-wave bursting at low doses and pseudo-plateau bursting at high doses, whereas Cd2+ is potentiating K(Ca), inducing pseudo-plateau bursting when applied in combination with low doses of 4-AP. Using bifurcation analysis, we show that spike adding in square-wave bursts is non-sequential when gradually changing HVA and K(Ca) maximum conductances, delayed Hopf is responsible for generating the plateau segment within the active phase of pseudo-plateau bursts, and bursting can become "chaotic" when HVA and K(Ca) maximum conductances are made low and high, respectively. These results highlight the secondary effects of the drugs applied and suggest that CSCs have all the ingredients needed for bursting.


Asunto(s)
4-Aminopiridina/farmacología , Potenciales de Acción/efectos de los fármacos , Cadmio/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Cerebelo/efectos de los fármacos , Bloqueadores de los Canales de Potasio/farmacología , Células de Purkinje/efectos de los fármacos , 4-Aminopiridina/administración & dosificación , Animales , Cadmio/administración & dosificación , Cerebelo/citología , Cerebelo/fisiología , Relación Dosis-Respuesta a Droga , Ratones , Ratones Endogámicos C57BL , Modelos Biológicos , Técnicas de Placa-Clamp , Células de Purkinje/fisiología
18.
South Med J ; 113(12): 629-632, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33263131

RESUMEN

Mentorship is vital in the effective progression of a physician's educational training. This journey often begins during a physician's undergraduate career prior to advancing on to medical school, residency, and fellowship training. These levels of training distinguish different tiers of mastery, and collaboration among these tiers is integral in order to facilitate a meaningful transition into an independent physician.


Asunto(s)
Educación Médica/organización & administración , Educación de Pregrado en Medicina/organización & administración , Humanos , Internado y Residencia/organización & administración , Mentores , Facultades de Medicina/organización & administración , South Carolina , Estudiantes de Medicina
19.
Mar Drugs ; 18(8)2020 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-32751216

RESUMEN

In early 2018, a large easterly storm hit the East Anglian coast of the UK, colloquially known as the 'Beast from the East', which also resulted in mass strandings of benthic organisms. There were subsequent instances of dogs consuming such organisms, leading to illness and, in some cases, fatalities. Epidemiological investigations identified paralytic shellfish toxins (PSTs) as the cause, with toxins present in a range of species and concentrations exceeding 14,000 µg STX eq./kg in the sunstar Crossaster papposus. This study sought to better elucidate the geographic spread of any toxicity and identify any key organisms of concern. During the summers of 2018 and 2019, various species of benthic invertebrates were collected from demersal trawl surveys conducted across a variety of locations in the North Sea. An analysis of the benthic epifauna using two independent PST testing methods identified a 'hot spot' of toxic organisms in the Southern Bight, with a mean toxicity of 449 µg STX eq./kg. PSTs were quantified in sea chervil (Alcyonidium diaphanum), the first known detection in the phylum bryozoan, as well as eleven other new vectors (>50 µg STX eq./kg), namely the opisthobranch Scaphander lignarius, the starfish Anseropoda placenta, Asterias rubens, Luidia ciliaris, Astropecten irregularis and Stichastrella rosea, the brittlestar Ophiura ophiura, the crustaceans Atelecyclus rotundatus and Munida rugosa, the sea mouse Aphrodita aculeata, and the sea urchin Psammechinus miliaris. The two species that showed consistently high PST concentrations were C. papposus and A. diaphanum. Two toxic profiles were identified, with one dominated by dcSTX (decarbamoylsaxitoxin) associated with the majority of samples across the whole sampling region. The second profile occurred only in North-Eastern England and consisted of mostly STX (Saxitoxin) and GTX2 (gonyautoxin 2). Consequently, this study highlights widespread and variable levels of PSTs in the marine benthos, together with the first evidence for toxicity in a large number of new species. These findings highlight impacts to 'One Health', with the unexpected sources of toxins potentially creating risks to animal, human and environmental health, with further work required to assess the severity and geographical/temporal extent of these impacts.


Asunto(s)
Organismos Acuáticos/química , Saxitoxina/análogos & derivados , Intoxicación por Mariscos , Animales , Crustáceos/química , Monitoreo del Ambiente , Mar del Norte , Saxitoxina/análisis , Erizos de Mar/química , Estrellas de Mar/química
20.
Science ; 368(6490)2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32355002

RESUMEN

Repeated bouts of exercise condition muscle mitochondria to meet increased energy demand-an adaptive response associated with improved metabolic fitness. We found that the type 2 cytokine interleukin-13 (IL-13) is induced in exercising muscle, where it orchestrates metabolic reprogramming that preserves glycogen in favor of fatty acid oxidation and mitochondrial respiration. Exercise training-mediated mitochondrial biogenesis, running endurance, and beneficial glycemic effects were lost in Il13-/- mice. By contrast, enhanced muscle IL-13 signaling was sufficient to increase running distance, glucose tolerance, and mitochondrial activity similar to the effects of exercise training. In muscle, IL-13 acts through both its receptor IL-13Rα1 and the transcription factor Stat3. The genetic ablation of either of these downstream effectors reduced running capacity in mice. Thus, coordinated immunological and physiological responses mediate exercise-elicited metabolic adaptations that maximize muscle fuel economy.


Asunto(s)
Adaptación Fisiológica/inmunología , Glucógeno/metabolismo , Interleucina-13/metabolismo , Mitocondrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Resistencia Física/inmunología , Animales , Glucemia/metabolismo , Línea Celular , Ácidos Grasos/metabolismo , Femenino , Humanos , Interleucina-13/sangre , Interleucina-13/genética , Subunidad alfa1 del Receptor de Interleucina-13/genética , Subunidad alfa1 del Receptor de Interleucina-13/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mioblastos/metabolismo , Oxidación-Reducción , Condicionamiento Físico Animal , Carrera , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo
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