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1.
Paediatr Anaesth ; 34(2): 112-120, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37927199

RESUMEN

BACKGROUND: During scoliosis surgery, motor evoked potentials (MEP), and somatosensory evoked potentials (SSEP) have been reported to be affected by the use of higher doses of anesthetic agents. Dexmedetomidine, a sympatholytic agent, an alpha-2 receptor agonist, has been used as an adjunctive agent to lower anesthetic dose. However, there is conflicting evidence regarding the effects of dexmedetomidine on the intraoperative neurophysiological monitoring of MEP and SSEP during surgery, particularly among pediatric patients. OBJECTIVES: This systematic review aimed to determine whether, during spinal fusion surgery in pediatric patients with scoliosis, dexmedetomidine alters MEP amplitude or SSEP latency and amplitude and, if so, whether different doses of dexmedetomidine display different effects (PROSPERO registration number CRD42022300562). METHODS: We searched PubMed, Scopus, and Cochrane Library on January 1, 2022 and included randomized controlled trials, observational cohort and case-control studies and case series investigating dexmedetomidine in the population of interest and comparing against a standardized anesthesia regimen without dexmedetomidine or comparing multiple doses of dexmedetomidine. Animal and in vitro studies and conference abstracts were excluded. RESULTS: We found substantial heterogeneity in the risk of bias (per Cochrane-preferred tools) of the included articles (n = 5); results are summarized without meta-analysis. Articles with the lowest risk of bias indicated that dexmedetomidine was associated with MEP loss and that higher doses of dexmedetomidine increased risk. In contrast, articles reporting no association between dexmedetomidine and MEP loss suffered from higher risk of bias, including suspected or confirmed problems with confounding, outcome measurement, participant selection, results reporting, and lack of statistical transparency and power. CONCLUSION: Given the limitations of the studies available in the literature, it would be advisable to conduct rigorous randomized controlled trials with larger sample sizes to assess the effects of dexmedetomidine use of in scoliosis surgery in pediatric patients.


Asunto(s)
Dexmedetomidina , Monitorización Neurofisiológica Intraoperatoria , Escoliosis , Humanos , Niño , Monitorización Neurofisiológica Intraoperatoria/métodos , Dexmedetomidina/farmacología , Escoliosis/cirugía , Potenciales Evocados Somatosensoriales/fisiología , Potenciales Evocados Motores/fisiología , Agonistas de Receptores Adrenérgicos alfa 2/farmacología , Estudios Retrospectivos
2.
Cochrane Database Syst Rev ; 11: CD013403, 2022 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-36326435

RESUMEN

BACKGROUND: Hereditary angioedema (HAE) is a serious and potentially life-threatening condition that causes acute attacks of swelling, pain and reduced quality of life. People with Type I HAE (approximately 80% of all HAE cases) have insufficient amounts of C1 esterase inhibitor (C1-INH) protein; people with Type II HAE (approximately 20% of all cases) may have normal C1-INH concentrations, but, due to genetic mutations, these do not function properly. A few people, predominantly females, experience HAE despite having normal C1-INH levels and C1-INH function (rare Type III HAE). Several new drugs have been developed to treat acute attacks and prevent recurrence of attacks. There is currently no systematic review and meta-analysis that included all preventive medications for HAE. OBJECTIVES: To assess the benefits and harms of interventions for the long-term prevention of HAE attacks in people with Type I, Type II or Type III HAE. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search date was 3 August 2021. SELECTION CRITERIA: We included randomised controlled trials in children or adults with HAE that used medications to prevent HAE attacks. The comparators could be placebo or active comparator, or both; approved and experimental drug trials were eligible for inclusion. There were no restrictions on dose, frequency or intensity of treatment. The minimum length of four weeks of treatment was required for inclusion; this criterion excluded the acute treatment of HAE attacks. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were 1. HAE attacks (number of attacks per person, per population) and change in number of HAE attacks; 2. mortality and 3. serious adverse events (e.g. hepatic dysfunction, hepatic toxicity and deleterious changes in blood tests). Our secondary outcomes were 4. quality of life; 5. severity of breakthrough attacks; 6. disability and 7. adverse events (e.g. weight gain, mild psychological changes and body hair). We used GRADE to assess certainty of evidence for each outcome. MAIN RESULTS: We identified 15 studies (912 participants) that met the inclusion criteria. The studies included people with Type I and II HAE. The studies investigated avoralstat, berotralstat, subcutaneous C1-INH, plasma-derived C1-INH, nanofiltered C1-INH, recombinant human C1-INH, danazol, and lanadelumab for the prevention of HAE attacks. We did not find any studies on the use of tranexamic acid for prevention of HAE attacks. All drugs except avoralstat reduced the number of HAE attacks compared with placebo. For breakthrough attacks that occurred despite prophylactic treatment, intravenous and subcutaneous forms of C1-INH and lanadelumab reduced attack severity. It is not known whether other drugs have a similar effect, as the severity of breakthrough attacks in people taking drugs other than C1-INH and lanadelumab was not reported. For quality of life, avoralstat, berotralstat, C1-INH (all forms) and lanadelumab increased quality of life compared with placebo; there were no data for danazol. Four studies reported on changes in disability during treatment with C1-INH, berotralstat and lanadelumab; all three drugs decreased disability compared with placebo. Adverse events, including serious adverse events, did not occur at a rate higher than placebo. However, serious adverse event data and other adverse event data were not available for danazol, which prevented us from drawing conclusions about the absolute or relative safety of this drug. No deaths were reported in the included studies. The analysis was limited by the small number of studies, the small number of participants in each study and the lack of data on older drugs, therefore the certainty of the evidence is low. Given the rarity of HAE, it is not surprising that drugs were rarely directly compared, which does not allow conclusions on the comparative efficacy of the various drugs for people with HAE. Finally, we did not identify any studies that included people with Type III HAE. Therefore, we cannot draw any conclusions about the efficacy or safety of any drug in people with this form of HAE. AUTHORS' CONCLUSIONS: The available data suggest that berotralstat, C1-INH (subcutaneous, plasma-derived, nanofiltered and recombinant), danazol and lanadelumab are effective in lowering the risk or incidence (or both) of HAE attacks. In addition, C1-INH and lanadelumab decrease the severity of breakthrough attacks (data for other drugs were not available). Avoralstat, berotralstat, C1-INH (all forms) and lanadelumab increase quality of life and do not increase the risk of adverse events, including serious adverse events. It is possible that danazol, subcutaneous C1-INH and recombinant human C1-INH are more effective than berotralstat and lanadelumab in reducing the risk of breakthrough attacks, but the small number of studies and the small size of the studies means that the certainty of the evidence is low. This and the lack of head-to-head trials prevented us from drawing firm conclusions on the relative efficacy of the drugs.


Asunto(s)
Angioedemas Hereditarios , Adulto , Niño , Femenino , Humanos , Masculino , Angioedemas Hereditarios/tratamiento farmacológico , Angioedemas Hereditarios/prevención & control , Angioedemas Hereditarios/inducido químicamente , Calidad de Vida , Danazol/uso terapéutico , Proteína Inhibidora del Complemento C1/uso terapéutico , Proteína Inhibidora del Complemento C1/efectos adversos , Administración Intravenosa , Resultado del Tratamiento
3.
J Physiol ; 599(17): 4117-4130, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34261189

RESUMEN

KEY POINTS: Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disorder of motor neurons, carrying a short survival. High-density motor unit recordings permit analysis of motor unit size (amplitude) and firing behaviour (afterhyperpolarization duration and muscle fibre conduction velocity). Serial recordings from biceps brachii indicated that motor units fired faster and with greater amplitude as disease progressed. First-recruited motor units in the latter stages of ALS developed characteristics akin to fast-twitch motor units, possibly as a compensatory mechanism for the selective loss of this motor unit subset. This process may become maladaptive, highlighting a novel therapeutic target to reduce motor unit vulnerability. ABSTRACT: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder with a median survival of 3 years. We employed serial high-density surface electromyography (HDSEMG) to characterize voluntary and ectopic patterns of motor unit (MU) firing at different stages of disease. By distinguishing MU subtypes with variable vulnerability to disease, we aimed to evaluate compensatory neuronal adaptations that accompany disease progression. Twenty patients with ALS and five patients with benign fasciculation syndrome (BFS) underwent 1-7 assessments each. HDSEMG measurements comprised 30 min of resting muscle and 1 min of light voluntary activity from biceps brachii bilaterally. MU decomposition was performed by the progressive FastICA peel-off technique. Inter-spike interval, firing pattern, MU potential area, afterhyperpolarization duration and muscle fibre conduction velocity were determined. In total, 373 MUs (ALS = 287; BFS = 86) were identified from 182 recordings. Weak ALS muscles demonstrated a lower mean inter-spike interval (82.7 ms) than strong ALS muscles (96.0 ms; P = 0.00919) and BFS muscles (95.3 ms; P = 0.0039). Mean MU potential area (area under the curve: 487.5 vs. 98.7 µV ms; P < 0.0001) and muscle fibre conduction velocity (6.2 vs. 5.1 m/s; P = 0.0292) were greater in weak ALS muscles than in BFS muscles. Purely fasciculating MUs had a greater mean MU potential area than MUs also under voluntary command (area under the curve: 679.6 vs. 232.4 µV ms; P = 0.00144). These results suggest that first-recruited MUs develop a faster phenotype in the latter stages of ALS, likely driven by the preferential loss of vulnerable fast-twitch MUs. Inhibition of this potentially maladaptive phenotypic drift may protect the longevity of the MU pool, stimulating a novel therapeutic avenue.


Asunto(s)
Esclerosis Amiotrófica Lateral , Electromiografía , Fasciculación , Humanos , Neuronas Motoras , Músculo Esquelético , Fenotipo
4.
Muscle Nerve ; 63(3): 392-396, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33290574

RESUMEN

INTRODUCTION: Prognostic uncertainty in amyotrophic lateral sclerosis (ALS) confounds clinical management planning, patient counseling, and trial stratification. Fasciculations are an early clinical hallmark of disease and can be quantified noninvasively. Using an innovative analytical method, we correlated novel fasciculation parameters with a predictive survival model. METHODS: Using high-density surface electromyography, we collected biceps recordings from ALS patients on their first research visit. By accessing an online survival prediction tool, we provided eight clinical and genetic parameters to estimate individual patient survival. Fasciculation analysis was performed using an automated algorithm (Surface Potential Quantification Engine), with a Cox proportional hazards model to calculate hazard ratios. RESULTS: The median predicted survival for 31 patients was 41 (interquartile range, 31.5-57) months. Univariate hazard ratios were 1.09 (95% confidence interval [CI], 1.03-1.16) for the rate of change of fasciculation frequency (RoCoFF) and 1.10 (95% CI, 1.01-1.19) for the amplitude dispersion rate. Only the RoCoFF remained significant (P = .04) in a multivariate model. DISCUSSION: Noninvasive measurement of fasciculations at a single time-point could enhance prognostic models in ALS, where higher RoCoFF values indicate shorter survival.


Asunto(s)
Esclerosis Amiotrófica Lateral/fisiopatología , Fasciculación/fisiopatología , Músculo Esquelético/fisiopatología , Anciano , Brazo , Electromiografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Tasa de Supervivencia
5.
Am J Obstet Gynecol ; 224(3): 258-265.e4, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32941790

RESUMEN

OBJECTIVE: After strong evidence and major organizations recommending salpingectomy over tubal ligation, we sought to perform a systematic review and meta-analysis comparing the intraoperative attributes and complication rates associated with these 2 procedures. DATA SOURCES: We searched PubMed, the Cochrane Library, Embase, and clinical trials registries without time or language restrictions. The search was conducted in February 2020. Database searches revealed 74 potential studies, of which 11 were examined at the full-text level. Of these, 6 studies were included in the qualitative analysis and 5 studies were included in the meta-analysis. STUDY ELIGIBILITY CRITERIA: We included randomized controlled trials comparing salpingectomy with tubal ligation in women seeking sterilization. We included studies that also had at least 1 outcome listed in the population/patient problem, intervention, comparison, outcome, and time. Articles were excluded if they did not meet the inclusion criteria or if data were not reported and the authors did not respond to inquiries. STUDY APPRAISAL AND SYNTHESIS METHODS: Abstracts and full-text articles were assessed by 2 authors independently using the blinded coding assignment function or EPPI-Reviewer 4. Conflicting selections were resolved by consensus. The quality of included studies was determined using the Cochrane Collaboration tool for assessing the risk of bias in randomized trials. Two authors independently assessed the risk of bias for each study; disagreements were resolved by consensus. RESULTS: There were few differences between the procedures, with no differences in most important clinical outcomes (antimüllerian hormone, blood loss, length of hospital stay, pre- or postoperative complications, or wound infections). A single study reported a reduced rate of pregnancies with salpingectomy (risk ratio, 0.22; 95% confidence interval, 0.05-1.02), but this did not reach statistical significance (P=.05). CONCLUSION: We conclude from these data that salpingectomy is as safe and efficacious as tubal ligation for sterilization and may be preferred, where appropriate, to reduce the risk of ovarian cancer.


Asunto(s)
Salpingectomía , Esterilización Reproductiva/métodos , Esterilización Tubaria , Femenino , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
6.
Anesth Analg ; 132(3): 686-695, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-32991330

RESUMEN

BACKGROUND: Although invasive monitoring is the standard method for intracranial pressure (ICP) measurement, it is not without potential for serious complications. Noninvasive methods have been proposed as alternatives to invasive ICP monitoring. The study aimed to investigate the diagnostic accuracy of the currently available noninvasive methods for intracranial hypertension (ICH) monitoring. METHODS: We searched 5 databases for articles evaluating the diagnostic accuracy of noninvasive methods in diagnosing ICH in PubMed, Institute of Science Index, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), and Embase. The quantitative analysis was conducted if there were at least 2 studies evaluating a specific method. The accuracy measures included the sensitivity, specificity, likelihood ratios, and diagnostic odds ratio. RESULTS: We included 134 articles. Ultrasonographic optic nerve sheath diameter (US ONSD) had high diagnostic accuracy (estimated sensitivity of 90%; 95% confidence interval [CI], 87-92, estimated specificity of 88%; 95% CI, 84-91) while the magnetic resonance imaging (MRI) ONSD had estimated sensitivity of 77%; 95% CI, 64-87 and estimated specificity of 89%; 95% CI, 84-93, and computed tomography (CT) ONSD had estimated sensitivity of 93%; 95% CI, 90-96 and estimated specificity of 79%; 95% CI, 56-92. All MRI signs had a very high estimated specificity ranging from 90% to 99% but a low estimated sensitivity except for sinus stenosis which had high estimated sensitivity as well as specificity (90%; 95% CI, 75-96 and 96%; 95% CI, 91-99, respectively). Among the physical examination signs, pupillary dilation had a high estimated specificity (86%; 95% CI, 76-93). Other diagnostic tests to be considered included pulsatility index, papilledema, transcranial Doppler, compression or absence of basal cisterns, and ≥10 mm midline shift. Setting the cutoff value of ICH to ≥20 mm Hg instead of values <20 mm Hg was associated with higher sensitivity. Moreover, if the delay between invasive and noninvasive methods was within 1 hour, the MRI ONSD and papilledema had a significantly higher diagnostic accuracy compared to the >1 hour subgroup. CONCLUSIONS: Our study showed several promising tools for diagnosing ICH. Moreover, we demonstrated that using multiple, readily available, noninvasive methods is better than depending on a single sign such as physical examination or CT alone.


Asunto(s)
Hipertensión Intracraneal/diagnóstico , Presión Intracraneal , Nervio Óptico/diagnóstico por imagen , Examen Físico , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Hipertensión Intracraneal/fisiopatología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neuroimagen , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Tomografía Computarizada por Rayos X , Ultrasonografía
7.
Crit Care Med ; 48(2): 233-240, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31939793

RESUMEN

OBJECTIVES: Tracheostomy is a very common clinical intervention in critically ill adult patients. The indications for tracheostomy procedures in pediatric patients with complex conditions have increased dramatically in recent years, but there are currently no guidelines on the optimal timing of tracheostomy in pediatric patients undergoing prolonged ventilation. DATA SOURCES: We performed a systematic search of the existing literature in MEDLINE via PubMed and Embase databases and the Cochrane Library to identify clinical trials, observational studies, and cohort studies that compare early and late tracheostomy in children. The date of the last search was August 27, 2018. Included articles were subjected to manual searching. STUDY SELECTION: Studies in mechanically ventilated children that compared early with late tracheostomy were included. DATA EXTRACTION: Data were extracted into a spreadsheet and copied into Review Manager 5.3 (The Cochrane Collaboration, Copenhagen, Denmark). DATA SYNTHESIS: Data were meta-analyzed using an inverse variance, random effects model. Continuous outcomes were calculated as mean differences with 95% CIs, and dichotomous outcomes were calculated as Mantel-Haenszel risk ratios with 95% CIs. We included eight studies (10 study arms). These studies were all retrospective cohort studies. Early tracheostomy was associated with significant reductions in mortality, days on mechanical ventilation, and length of intensive care and total hospital stay, although the lack of randomized, controlled trials limits the validity of these findings. Although variance was imputed for some studies, these conclusions did not change after removing these studies from the analysis. CONCLUSIONS: In children on mechanical ventilation, early tracheostomy may improve important medical outcomes. However, our data demonstrate the urgent need for high-quality, randomized controlled trials in the pediatric population.


Asunto(s)
Respiración Artificial/estadística & datos numéricos , Traqueostomía/métodos , Adolescente , Niño , Preescolar , Cuidados Críticos , Enfermedad Crítica , Humanos , Lactante , Unidades de Cuidados Intensivos , Tiempo de Internación , Estudios Retrospectivos , Factores de Tiempo , Traqueostomía/mortalidad
8.
Muscle Nerve ; 61(6): 745-750, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32208527

RESUMEN

INTRODUCTION: Fasciculations represent early neuronal hyperexcitability in amyotrophic lateral sclerosis (ALS). To aid calibration as a disease biomarker, we set out to characterize the daytime variability of fasciculation firing. METHODS: Fasciculation awareness scores were compiled from 19 ALS patients. In addition, 10 ALS patients prospectively underwent high-density surface electromyographic (HDSEMG) recordings from biceps and gastrocnemius at three time-points during a single day. RESULTS: Daytime fasciculation awareness scores were low (mean: 0.28 muscle groups), demonstrating significant variability (coefficient of variation: 303%). Biceps HDSEMG recordings were highly consistent for fasciculation potential frequency (intraclass correlation coefficient [ICC] = 95%, n = 19) and the interquartile range of fasciculation potential amplitude (ICC = 95%, n = 19). These parameters exhibited robustness to observed fluctuations in data quality parameters. Gastrocnemius demonstrated more modest levels of consistency overall (44% to 62%, n = 20). DISCUSSION: There was remarkable daytime consistency of fasciculation firing in the biceps of ALS patients, despite sparse and intermittent awareness among patients' accounts.


Asunto(s)
Esclerosis Amiotrófica Lateral/diagnóstico , Esclerosis Amiotrófica Lateral/fisiopatología , Fasciculación/diagnóstico , Fasciculación/fisiopatología , Músculo Esquelético/fisiopatología , Anciano , Anciano de 80 o más Años , Electromiografía/tendencias , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Autoinforme , Factores de Tiempo
9.
Cardiovasc Diabetol ; 18(1): 14, 2019 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-30700294

RESUMEN

BACKGROUND: Carotid artery intima-media thickness (cIMT) progression is a surrogate marker of atherosclerosis with a high predictive value for future CVD risk. This study evaluates the comparative efficacies of lipid lowering, hypoglycemic, antihypertensive and antiplatelet medications on cIMT progression. METHODS: We conducted a network meta-analysis (NMA) to evaluate the relative efficacies of several drug classes in modifying cIMT progression. After a literature search in several electronic databases, studies were selected by following predetermined eligibility criteria. An inverse variance-heterogeneity model was used for NMA. Sensitivity analyses were performed to check the reliability of the overall NMA, and transitivity analyses were performed to examine the effects of modifiers on the NMA outcomes. RESULTS: Data were taken from 47 studies (15,721 patients; age: 60.2 years [95% confidence interval (CI) 58.8, 61.6]; BMI: 27.2 kg/m2 [95% CI 26.4, 28.0]; and gender: 58.3% males [95% CI 48.3, 68.3]). Treatment duration was 25.8 months [95% CI 22.9, 28.7]. Of the 13 drug classes in the network, treatment with phosphodiesterase III inhibitors was the most effective in retarding annual mean cIMT against network placebo (weighted mean difference (WMD) - 0.059 mm [95% CI - 0.099, - 0.020) followed by the calcium channel blockers (WMD - 0.055 mm [95% CI - 0.099, 0.001]) and platelet adenosine diphosphate inhibitors (WMD - 0.033 mm [95% CI - 0.058, 0.008]). These 3 drug classes also attained the same positions when the NMA was conducted by using first-year changes in mean cIMT. In transitivity analyses, longer treatment duration, higher body mass index (BMI), and a higher baseline cIMT were found to be independently associated with a lesser reduction in annual mean cIMT. However, in a multivariate analysis with these 3 modifiers, none of these factors was significantly associated with annual change in mean cIMT. In the placebo group, age was inversely associated with annual change in mean cIMT independently. CONCLUSION: Phosphodiesterase III inhibitors and calcium channel blockers are found more effective than other drug classes in retarding cIMT progression. Age, BMI, and baseline cIMT may have some impact on these outcomes.


Asunto(s)
Antihipertensivos/uso terapéutico , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/tratamiento farmacológico , Grosor Intima-Media Carotídeo , Hipoglucemiantes/uso terapéutico , Hipolipemiantes/uso terapéutico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Bloqueadores de los Canales de Calcio/uso terapéutico , Enfermedades de las Arterias Carótidas/epidemiología , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Inhibidores de Fosfodiesterasa 3/uso terapéutico , Valor Predictivo de las Pruebas , Factores de Tiempo , Resultado del Tratamiento
11.
Br J Nutr ; 114(4): 503-8, 2015 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-26202329

RESUMEN

Low vitamin B12 status is common in older people; however, its public health significance in terms of neurological manifestations remains unclear. The present systematic review evaluated the association of vitamin B12 status with neurological function and clinically relevant neurological outcomes in adults aged 50+ years. A systematic search of nine bibliographic databases (up to March 2013) identified twelve published articles describing two longitudinal and ten cross-sectional analyses. The included study populations ranged in size (n 28-2287) and mean/median age (range 65-81 years). Studies reported various neurological outcomes: nerve function; clinically measured signs and symptoms of nerve function; self-reported neurological symptoms. Studies were assessed for risk of bias, and results were synthesised qualitatively. Among the general population groups of older people, one longitudinal study reported no association, and four of seven cross-sectional studies reported limited evidence of an association of vitamin B12 status with some, but not all, neurological outcomes. Among groups with clinical and/or biochemical evidence of low vitamin B12 status, one longitudinal study reported an association of vitamin B12 status with some, but not all, neurological outcomes and three cross-sectional analyses reported no association. Overall, there is limited evidence from observational studies to suggest an association of vitamin B12 status with neurological function in older people. The heterogeneity and quality of the evidence base preclude more definitive conclusions, and further high-quality research is needed to better inform understanding of public health significance in terms of neurological function of vitamin B12 status in older people.


Asunto(s)
Envejecimiento/fisiología , Estado de Salud , Sistema Nervioso , Vitamina B 12/sangre , Complejo Vitamínico B/sangre , Anciano , Humanos
12.
Brain Commun ; 6(2): fcae061, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38487552

RESUMEN

Sensory processing and sensorimotor integration are abnormal in dystonia, including impaired modulation of beta-corticomuscular coherence. However, cortex-muscle interactions in either direction are rarely described, with reports limited predominantly to investigation of linear coupling, using corticomuscular coherence or Granger causality. Information-theoretic tools such as transfer entropy detect both linear and non-linear interactions between processes. This observational case-control study applies transfer entropy to determine intra- and cross-frequency cortex-muscle coupling in young people with dystonia/dystonic cerebral palsy. Fifteen children with dystonia/dystonic cerebral palsy and 13 controls, aged 12-18 years, performed a grasp task with their dominant hand. Mechanical perturbations were provided by an electromechanical tapper. Bipolar scalp EEG over contralateral sensorimotor cortex and surface EMG over first dorsal interosseous were recorded. Multi-scale wavelet transfer entropy was applied to decompose signals into functional frequency bands of oscillatory activity and to quantify intra- and cross-frequency coupling between brain and muscle. Statistical significance against the null hypothesis of zero transfer entropy was established, setting individual 95% confidence thresholds. The proportion of individuals in each group showing significant transfer entropy for each frequency combination/direction was compared using Fisher's exact test, correcting for multiple comparisons. Intra-frequency transfer entropy was detected in all participants bidirectionally in the beta (16-32 Hz) range and in most participants from EEG to EMG in the alpha (8-16 Hz) range. Cross-frequency transfer entropy across multiple frequency bands was largely similar between groups, but a specific coupling from low-frequency EMG to beta EEG was significantly reduced in dystonia [P = 0.0061 (corrected)]. The demonstration of bidirectional cortex-muscle communication in dystonia emphasizes the value of transfer entropy for exploring neural communications in neurological disorders. The novel finding of diminished coupling from low-frequency EMG to beta EEG in dystonia suggests impaired cortical feedback of proprioceptive information with a specific frequency signature that could be relevant to the origin of the excessive low-frequency drive to muscle.

13.
Hepatology ; 55(2): 373-83, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21953491

RESUMEN

UNLABELLED: Human hepatitis B virus (HBV) is characterized by a high species specificity and a distinct liver tropism. Within the liver, HBV replication occurs in differentiated and polarized hepatocytes. Accordingly, the in vitro HBV infection of primary human hepatocytes (PHHs) and the human hepatoma cell line, HepaRG, is restricted to differentiated, hepatocyte-like cells. Though preparations of PHH contain up to 100% hepatic cells, cultures of differentiated HepaRG cells are a mixture of hepatocyte-like and biliary-like epithelial cells. We used PHH and HepaRG cells and compared the influence of virus inoculation dose, cell differentiation, and polarization on productive HBV infection. At multiplicities of genome equivalents (mge) >8,000, almost 100% of PHHs could be infected. In contrast, only a subset of HepaRG cells stained positive for HBcAg at comparable or even higher mge. Infection predominantly occurred at the edges of islands of hepatocyte-like HepaRG cells. This indicates a limited accessibility of the HBV receptor, possibly as a result of its polar sorting. Multidrug resistance protein 2 (MRP2), a marker selectively transported to the apical (i.e., canalicular) cell membrane, revealed two polarization phenotypes of HepaRG cells. HBV infection within the islands of hepatocyte-like HepaRG cells preferentially occurred in cells that resemble PHH, exhibiting canalicular structures. However, disruption of cell-cell junctions allowed the additional infection of cells that do not display a PHH-like polarization. CONCLUSION: HBV enters hepatocytes via the basolateral membrane. This model, at least partially, explains the difference of PHH and HepaRG cells in infection efficacy, provides insights into natural HBV infection, and establishes a basis for optimization of the HepaRG infection system.


Asunto(s)
Polaridad Celular , Virus de la Hepatitis B/fisiología , Hepatocitos/virología , Interacciones Huésped-Patógeno , Internalización del Virus , Línea Celular Tumoral , Hepatitis B/virología , Humanos , Uniones Intercelulares
14.
Acta Orthop ; 84(6): 579-84, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24171677

RESUMEN

BACKGROUND: and purpose Limb lengthening is performed for a diverse range of orthopedic problems. A high rate of complications has been reported in these patients, which include motor and sensory loss as a result of nerve damage. We investigated the effect of limb lengthening on peripheral nerve function. PATIENTS AND METHODS: 36 patients underwent electrophysiological testing at 3 points: (1) preoperatively, (2) after application of external fixator/corticotomy but before lengthening, and (3) after lengthening. The limb-length discrepancy was due to a congenital etiology (n = 19), a growth disturbance (n = 9), or a traumatic etiology (n = 8). RESULTS: 2 of the traumatic etiology patients had significant changes evident on electrophysiological testing preoperatively. They both deteriorated further with lengthening. 7 of the 21 patients studied showed deterioration in nerve function after lengthening, but not postoperatively, indicating that this was due to the lengthening process and not to the surgical procedure. All of these patients had a congenital etiology for their leg-length discrepancy. INTERPRETATION: As detailed electrophysiological tests were carried out before surgery, after surgery but before lengthening, and finally after completion of lengthening, it was possible to distinguish between the effects of the operation and the effects of lengthening on nerve function. The results indicate that the etiology, site (femur or tibia), and nerve (common peroneal or tibial) had a bearing on the risk of nerve injury and that these factors had a far greater effect than the total amount of lengthening.


Asunto(s)
Técnica de Ilizarov/efectos adversos , Diferencia de Longitud de las Piernas/cirugía , Conducción Nerviosa/fisiología , Traumatismos de los Nervios Periféricos/etiología , Adolescente , Niño , Electromiografía/métodos , Fijadores Externos , Fémur/anomalías , Fémur/cirugía , Humanos , Diferencia de Longitud de las Piernas/congénito , Diferencia de Longitud de las Piernas/etiología , Traumatismos de los Nervios Periféricos/diagnóstico , Traumatismos de los Nervios Periféricos/fisiopatología , Tiempo de Reacción/fisiología , Factores de Riesgo , Tibia/anomalías , Tibia/cirugía , Resultado del Tratamiento
15.
Front Med (Lausanne) ; 10: 1089361, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36744141

RESUMEN

Background: Photodynamic therapy (PDT) is increasingly used for the treatment of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). However, it is unknown whether photodynamic therapy is more effective than other commonly used treatment modalities for these cancers. Purpose: The aim of this study was to determine the relative efficacy and safety of PDT compared with placebo or other interventions for the treatment of skin carcinomas. Methods: Searches were performed in PubMed, Web of Science, Embase, and the Cochrane Central Register of Controlled Trials databases. We included randomized controlled trials comparing the PDT with other interventions in adults skin BCC or SCC that reported on lesion response, recurrence, cosmetic appearance, or safety outcomes. Results: Seventeen unique randomized controlled trials, representing 22 study arms from 21 publications were included. The included trials included 2,166 participants, comparing methyl aminolevulinic (MAL) PDT (six studies) or aminolevulinic acid (ALA) PDT (two studies). Comparators included placebo, surgery, hexaminolevulinic (HAL) PDT, erbium: yttrium-aluminum-garnet ablative factional laser (YAG-AFL) PDT, fluorouracil, and imiquimod. There were few studies available for each comparison. Mantel-Haenszel fixed effects risk ratios were calculated for response, recurrence, cosmetic outcomes, and adverse events. MAL-PDT had similar response rates to surgery, ALA-PDT, fluorouracil and imiquimod at 3- and 12 months post-intervention. The rate of recurrence was similar, showing few differences at 12 months, but at later time points (24-60 months), fewer lesions recurred with surgery and imiquimod than with PDT. PDT also caused more adverse events and pain than other interventions. However, PDT treatment was more likely to receive a "good" or "excellent" rating for cosmetic appearance than surgery or cryotherapy. Conclusion: This systematic review and meta-analysis demonstrates that the choice of treatment modality for BCC or SCC is best chosen in the context of the location and size of the lesion, the socioeconomic circumstances of the patient, as well as the patient's preferences. We call for more high quality studies to be done, in order to enable more reliable interpretations of the data. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=368626, identifier CRD42022368626.

16.
Drugs ; 83(6): 531-546, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36943634

RESUMEN

BACKGROUND: Nutritional therapies are effective alternative treatments for male infertility or subfertility. These are cost-effective and easily implementable, unlike other advanced invasive treatments. Even moderate improvements in sperm quality could improve spontaneous pregnancy. OBJECTIVE: We aimed to compare the effectiveness of all nutritional therapies in male infertility/subfertility treatment and ranked their efficacy based on type and etiology. We intend to aid clinicians with an evidence-based approach to affordable and safer initial infertility treatment for those who mainly do not wish to have other advanced invasive treatments or could not afford or have access to them. METHODS: We included 69 studies with 94 individual study arms identified from bibliographic databases and registries. We included studies in adult men with proven infertility or subfertility that investigated nutritional or dietary supplement therapies compared with control or placebo and at least reported on a sperm parameter. We undertook a network meta-analysis and performed a pairwise meta-analysis on all sperm parameter outcomes and meta-regression. No language or date restriction was imposed. A systematic article search was concluded on August 29, 2022. RESULTS: Our network meta-analysis is the first to compare all dietary interventions in a single analysis, sub-grouped by intervention type and type of infertility. L-Carnitine with micronutrients, antioxidants, and several traditional herbal supplements showed statistically and clinically significant improvement in sperm quality. Meta-regression identified that improvement in the sperm count, motility and morphology translated into increased pregnancy rates (p < 0.001; p < 0.001; p < 0.002, respectively). In particular, L-carnitine with micronutrient therapy (risk ratio [RR]: 3.60, 95% CI 1.86, 6.98, p = 0.0002), followed by zinc (RR 5.39, 95% CI 1.26, 23.04, p = 0.02), significantly improved pregnancy rates. Men with oligozoospermia (RR 4.89), followed by oligoasthenozoospermia (RR 4.20) and asthenoteratozoospermia (RR 3.53), showed a significant increase in pregnancy rates. CONCLUSION: We ranked nutritional therapies for their ability to improve sperm quality in men with infertility. Nutritional therapies, particularly L-carnitine alone or combined with micronutrients, significantly improved sperm parameters and pregnancy rates even under severe conditions. We believe these affordable solutions may be valuable for people without access to or who do not wish to undergo more invasive and costly fertility treatments.


Asunto(s)
Infertilidad Masculina , Semen , Embarazo , Adulto , Femenino , Masculino , Humanos , Metaanálisis en Red , Infertilidad Masculina/tratamiento farmacológico , Infertilidad Masculina/etiología , Micronutrientes/uso terapéutico , Carnitina/uso terapéutico
17.
Muscle Nerve ; 45(5): 635-41, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22499088

RESUMEN

INTRODUCTION: We assessed the clinical impact of replacing standard neurophysiologic testing with a hand-held device (Mediracer) for diagnosis of carpal tunnel syndrome (CTS). METHODS: One hundred patients (200 hands) with suspected CTS were studied by blinded assessors [Hand-therapist (HT)1 and Consultant Neurophysiologist] using the Mediracer, followed by standard neurophysiologic testing. To simulate testing by personnel without neurological training, Mediracer recordings were analyzed separately by an assessor who had not seen the patients (HT2). RESULTS: Correlation of the CTS grades was 0.94 for the results obtained by HT1, and 0.87 for HT2. The sensitivity and specificity of the Mediracer was 0.85 and 0.9, respectively, by HT1, and 0.84 and 0.89 for HT2. Nine patients had conditions other than CTS, and 35 patients were judged to require further investigation. CONCLUSIONS: The Mediracer should only be used in patients with typical CTS symptoms and signs and no muscle wasting who have had careful neurological assessment.


Asunto(s)
Síndrome del Túnel Carpiano/diagnóstico , Mano , Conducción Nerviosa/fisiología , Examen Neurológico/instrumentación , Examen Neurológico/métodos , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Síndrome del Túnel Carpiano/fisiopatología , Estimulación Eléctrica/instrumentación , Estimulación Eléctrica/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Estadística como Asunto , Adulto Joven
18.
Exp Brain Res ; 219(2): 275-92, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22526947

RESUMEN

The purpose of this study was to investigate the effects of peripheral afferent stimuli on the synchrony between brain and muscle activity as estimated by corticomuscular coherence (CMC). Electroencephalogram (EEG) from sensorimotor cortex and electromyogram (EMG) from two intrinsic hand muscles were recorded during a key grip motor task, and the modulation of CMC caused by afferent electrical and mechanical stimulation was measured. The particular stimuli used were graded single-pulse electrical stimuli, above threshold for perception and activating cutaneous afferents, applied to the dominant or non-dominant index finger, and a pulsed mechanical displacement of the gripped object causing the subject to feel as if the object may be dropped. Following electrical stimulation of the dominant index finger, the level of ß-range (14-36 Hz) CMC was reduced in a stimulus intensity-dependent fashion for up to 400 ms post-stimulus, then returned with greater magnitude before falling to baseline levels over 2.5 s, outlasting the reflex and evoked changes in EMG and EEG. Subjects showing no baseline ß-range CMC nevertheless showed post-stimulus increases in ß-range CMC with the same time course as those with baseline ß-range CMC. The mechanical stimuli produced similar modulation of ß-range CMC. Electrical stimuli to the non-dominant index finger produced no significant increase in ß-range CMC. The results suggest that both cutaneous and proprioceptive afferents have access to circuits generating CMC, but that only a functionally relevant stimulus produces significant modulation of the background ß-range CMC, providing further evidence that ß-range CMC has an important role in sensorimotor integration.


Asunto(s)
Corteza Motora/fisiología , Nervios Periféricos/fisiología , Estimulación Física/métodos , Desempeño Psicomotor/fisiología , Adulto , Estimulación Eléctrica/métodos , Electroencefalografía/métodos , Femenino , Fuerza de la Mano/fisiología , Humanos , Contracción Isométrica/fisiología , Masculino , Persona de Mediana Edad , Adulto Joven
19.
IEEE Trans Biomed Eng ; 69(2): 771-782, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34398749

RESUMEN

OBJECTIVE: Functional coupling between the motor cortex and muscle activity is commonly detected and quantified by cortico-muscular coherence (CMC) or Granger causality (GC) analysis, which are applicable only to linear couplings and are not sufficiently sensitive: some healthy subjects show no significant CMC and GC, and yet have good motor skills. The objective of this work is to develop measures of functional cortico-muscular coupling that have improved sensitivity and are capable of detecting both linear and non-linear interactions. METHODS: A multiscale wavelet transfer entropy (TE) methodology is proposed. The methodology relies on a dyadic stationary wavelet transform to decompose electroencephalogram (EEG) and electromyogram (EMG) signals into functional bands of neural oscillations. Then, it applies TE analysis based on a range of embedding delay vectors to detect and quantify intra- and cross-frequency band cortico-muscular coupling at different time scales. RESULTS: Our experiments with neurophysiological signals substantiate the potential of the developed methodologies for detecting and quantifying information flow between EEG and EMG signals for subjects with and without significant CMC or GC, including non-linear cross-frequency interactions, and interactions across different temporal scales. The obtained results are in agreement with the underlying sensorimotor neurophysiology. CONCLUSION: These findings suggest that the concept of multiscale wavelet TE provides a comprehensive framework for analyzing cortex-muscle interactions. SIGNIFICANCE: The proposed methodologies will enable developing novel insights into movement control and neurophysiological processes more generally.


Asunto(s)
Corteza Motora , Músculo Esquelético , Electroencefalografía/métodos , Electromiografía/métodos , Entropía , Humanos , Corteza Motora/fisiología , Músculo Esquelético/fisiología
20.
J Neurol Neurosurg Psychiatry ; 82(5): 549-51, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-20462913

RESUMEN

A practical issue in the diagnosis of amyotrophic lateral sclerosis (ALS) is how long the EMG must be observed before a muscle can be declared free of fasciculations with some degree of certainty. To answer this question, the intervals between fasciculation potentials (FPs) were recorded from 53 muscles of 19 ALS patients. The distribution of the FP intervals found across the sample showed that to record a single fasciculation with a probability approaching unity, observation for up to 90 s may be required.


Asunto(s)
Esclerosis Amiotrófica Lateral/fisiopatología , Fasciculación/fisiopatología , Músculo Esquelético/fisiopatología , Esclerosis Amiotrófica Lateral/diagnóstico , Electromiografía/métodos , Fasciculación/diagnóstico , Humanos , Factores de Tiempo
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