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BACKGROUND: Magnetically controlled growing rods (MCGR) aim to control curve progression while limiting surgical burden in children with early-onset scoliosis. Systemic and local distribution of metal debris has been documented in children with spinal implants. The aim of the study was to assess serum metal ion levels and local metal debris-related changes at the conclusion of MCGR treatment. METHODS: Between February 2019 and September 2022, all patients who had a conversion to definitive fusion at the completion of MCGR treatment in our institution were invited to participate in this study. Consenting patients had serum metal ion levels drawn (titanium, cobalt, and chromium) and histologic analyses of peri-implant tissue samples. RESULTS: We enrolled 24 children who underwent definitive fusion post-MCGR treatment for early-onset scoliosis. The average age at definitive fusion was 13.3 years (range: 11 to 17 y). The average length of MCGR treatment was 4.8 years (range: 1.5 to 6.8 y). At the end of the MCGR treatment, 23 (96%) patients had elevated serum metal ion levels. Mean serum titanium levels were 165.4 nmol/L (range: 30 to 390 nmol/L), mean serum cobalt levels were 4.6 nmol/L (range: 1.2 to 14 nmol/L), and mean serum chromium levels were 14 nmol/L (range: 2.4 to 30 nmol/L). Peri-implant soft tissue histologic analysis demonstrated local metal debris and foreign body reactions in all patients. CONCLUSIONS: At the completion of MCGR treatment, the majority of patients demonstrate elevated serum metal ion levels and local metal debris-related peri-implant soft tissue changes. Although there is no current literature to suggest these findings are harmful, further research as to the clinical significance is required. LEVEL OF EVIDENCE: Level IV.
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Escoliosis , Niño , Humanos , Adolescente , Escoliosis/cirugía , Titanio , Columna Vertebral/cirugía , Cobalto , Cromo , Estudios RetrospectivosRESUMEN
BACKGROUND: The management of congenital scoliosis poses a significant challenge for treating surgeons. The aim of our study was to provide insight into the long-term clinical results of spinal fusion in congenital scoliosis. METHODS: We performed a retrospective review of the scoliosis database in our institution for the period 1976 until 2002 identifying 43 patients with congenital scoliosis who underwent spinal fusion. Patient demographics, diagnosis, levels fused, and radiographs were evaluated. Patients were evaluated for unplanned return to the operating room (UPROR) via SRS 22, EQ5D-5L, and Oswestry Disability Index (ODI). RESULTS: Of the 43 patients who fulfilled the inclusion criteria, 22 patients agreed to participate, 3 patients were known to be deceased and 18 patients were lost to follow-up or declined to participate and were excluded. The mean age of the respondents was 40.7 years (range, 30 to 47 y) with a mean follow-up from index surgery of 35 years (range, 20 to 44 y). At most recent follow-up, 12 patients (54%) underwent UPROR. The mean age at diagnosis was 3.4 years (range, birth to 11.5 y), and the mean age for first surgery was 5.8 years (range, 1 to 13 y). As regards radiologic follow-up; the mean number of levels fused was 5.2 (range, 2 to 12). Thoracic fusion was performed in 17 patients (77%). The mean T1 to T12 height at index surgery and maturity was 166 mm (range, 130 to 240 mm) and 202 mm (range, 125 to 270 mm), respectively. The mean functional scores at follow-up were SRS 22: 4.5 (range, 2.4 to 5), cumulative EQ5D-5L score 7.2 (range, 5 to 15), and ODI: 8% (range, 2 to 30%). All respondents completed high school, 10 patients (45%) completed university, and 2 patients were awarded doctorates. Currently, 17 patients (77%) are in paid employment. CONCLUSIONS: This report constitutes the largest series of patients treated by spinal arthrodesis for congenital scoliosis followed into maturity. We demonstrate the thorax continues to grow after index fusion, patient-reported outcomes were satisfactory with superior educational and employment rates and unplanned return to theatre is rare in adult life. LEVEL OF EVIDENCE: Therapeutic Level IV.
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Escoliosis , Fusión Vertebral , Adulto , Humanos , Persona de Mediana Edad , Niño , Lactante , Preescolar , Adolescente , Escoliosis/diagnóstico por imagen , Escoliosis/cirugía , Estudios de Seguimiento , Resultado del Tratamiento , Estudios Retrospectivos , Fusión Vertebral/métodosRESUMEN
BACKGROUND: Early-onset scoliosis (EOS) is frequently associated with complex spine and chest wall deformities that may lead to severe cardiopulmonary impairment and malnutrition. The aim of this study is to evaluate the change in the nutritional status of EOS patients after treatment with magnetically controlled growing rod instrumentation (MCGR) in a single center. METHODS: We prospectively collected data of patients treated with MCGR for EOS in a single center. Exclusion criteria were <2 years' follow-up and incomplete weight-for-age Z-scores (WAZ) data. Preoperative and postoperative WAZ, radiographic parameters, including major coronal curve, kyphosis angle, space available for lung ratios, thoracic height, and unplanned returns to the operating room (UPROR), were analyzed. SD and 95% Confidence intervals (CI) are presented with means. RESULTS: Sixty-eight patients (37 males/31 females) were included. The mean age at surgery was 8.2 years (SD 2.8, range 1.8-14.2), and the mean follow-up time was 3.8 years (SD 1.0, range 2.1-6.8). The study population was categorized by the primary diagnosis as follows: 23 neuromuscular, 18 idiopathic, 15 congenital, and 12 syndromic patients. The major coronal curve improved between the preoperative and latest visits by 40% ( P <0.005, SD 27, CI 33-47), while the space available for lung ratios improved by 8% ( P <0.005, SD 13, CI 5-12). Thoracic height increased by 25% ( P <0.005, SD 13, CI 22-28), and kyphosis angle decreased by 25% ( P <0.005, SD 26, CI 9-39). Eighteen patients (27%) required a total of 53 UPRORs. WAZ improved significantly between the preoperative and the latest follow-up ( P =0.005). Regression analysis showed WAZ improvements were most significant in the underweight patients and the Idiopathic or Syndromic EOS patients. UPROR was not associated with deterioration in WAZ. CONCLUSIONS: Treatment of EOS patients with MCGR resulted in an improvement in nutritional status, as evidenced by the significant increase in WAZ. Underweight, Idiopathic and Syndromic EOS patients, and those who required UPROR all had significant improvement in their WAZ with MCGR treatment. LEVEL OF EVIDENCE: Therapeutic Study-Level II.
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Cifosis , Escoliosis , Masculino , Femenino , Humanos , Lactante , Preescolar , Niño , Adolescente , Escoliosis/cirugía , Estudios de Seguimiento , Delgadez , Resultado del Tratamiento , Cifosis/cirugía , Aumento de Peso , Estudios RetrospectivosRESUMEN
INTRODUCTION: Twenty-five-hydroxy-vitamin D3 (25-OH-vit D) is a prohormone that is essential for normal calcium homeostasis and bone metabolism. Understanding its role is an important component of the proper care of the pediatric orthopaedic patient. The aim of this study was to determine whether children in Ireland with fractures have increased prevalence of 25-OH-Vit D deficiency compared with age matched controls and to ascertain the relationship between a low 25-OH-vit D level and the incidence of fractures in Irish children. We hypothesised that children presenting to our centre following a fracture would have significantly lower 25-OH-vit D. METHODS: A prospective case-control study at a large urban tertiary referral academic hospital located in Dublin, Ireland was completed over a 14 month period from June 2014 to August 2015. A total of 116 subjects, distributed as cases (n = 58) and controls (n = 58) were included in this study. Whole blood (10 ml) was taken in two serum bottles from each patient. Serum 25-hydroxy-vitamin D3 levels were measured. An age matched control group was generated from other children attending the hospital, who also had vitamin D levels measured for different clinical reasons. We followed up both the fracture and control group for the next 5 years to assess the repeat fracture rate. RESULTS: Fifty-eight patients with a fracture requiring operative intervention, were included in the study. Statistical analysis was performed comparing to 58 age and sex-matched controls. The mean vitamin D level for the fracture group was 63.2 nmol/L (SD = 27.3), which was higher than the mean of the controls (62.5 nmol/L) (SD = 21.3) (p = 0.86), but this difference was found not to be statistically significant in unadjusted analysis. There was no statistically significant difference in the number of patients classified with low serum Vitamin D levels (<50 nmolL), with the fracture group consisting of 22 (37.9%) patients, and the control group of 17 patients (29.3%) (p = 0.33) with a level below 50 nmol/L. At five-year follow-up, 11 of the 58 patients (18.9%) in the fracture group went on to have a further fracture compared with eight patients (13.7%) from the control group. Out of these 11 from the fracture group five (45.45%) had been found to have a low serum 25-OH-Vit D level five years previously. Out of the eight controls that presented with a fracture within the five-year period, 3 (37.5%) had had a low vitamin D level at the origin of this study. CONCLUSION: The results of this study show that children presenting to our institution with low energy fractures have a prevalence of 38% 25-hydroxy-vitamin D deficiency. This study included children from age 1 to 16 primarily Caucasian encompassing all fracture types resulting from accidental trauma. Our findings suggest that in an Irish pediatric population vitamin D status may impact fracture risk with more than one-third being deficient in this review.
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Fracturas Óseas , Deficiencia de Vitamina D , Adolescente , Estudios de Casos y Controles , Niño , Preescolar , Estudios de Seguimiento , Fracturas Óseas/epidemiología , Humanos , Lactante , Vitamina D , Deficiencia de Vitamina D/complicaciones , Deficiencia de Vitamina D/epidemiologíaRESUMEN
BACKGROUND: A fundamental tenent of treating developmental dysplasia of the hip is to identify patients with dislocated hips early so as to avoid the long-term sequelae of late diagnosis. The aim of this study was to develop a readily useable triage tool for patients with suspected hip dislocation, based on the clinical history and examination findings of the referring practitioner. METHODS: All primary care referrals (n=934) over a 3-year period for suspected developmental dysplasia of the hip to a tertiary pediatric center were evaluated. Defined parameters with respect to history and clinical examination were evaluated. Multivariable logistic regression was used to establish predictors of hip dislocation, and from this a predictive model was derived which incorporated significant predictors of dislocation. An illustrative nomogram translated this predictive model into a usable numerical scoring system called the Children's Hip Prediction score, which estimates probability of hip dislocation. RESULTS: There were 97 dislocated hips in 85 patients. The final predictive model included age, sex, family history, breech, gait concerns, decreased abduction, leg length discrepancy, and medical/neurological syndrome. The area under receiver operating curve for the model is 0.761. A Children's Hip Prediction score of≥5 corresponds to a sensitivity of 76.3% and a score of≥15 has a specificity of 97.8%, corresponding to an odds ratio of 27.3 for increased risk of dislocation. CONCLUSION: We found that a novel clinical prediction score, based on readily available history and examination parameters strongly predicted risk of dislocations in hip dysplasia referral. It is hoped that this tool could be utilized to optimize resource allocation and may be of particular benefit in less well-resourced health care systems. LEVEL OF EVIDENCE: Level II.
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Displasia del Desarrollo de la Cadera , Luxación Congénita de la Cadera , Luxación de la Cadera , Luxaciones Articulares , Niño , Luxación de la Cadera/diagnóstico , Luxación Congénita de la Cadera/diagnóstico , Luxación Congénita de la Cadera/terapia , Humanos , Derivación y Consulta , Estudios Retrospectivos , Factores de Riesgo , TriajeRESUMEN
BACKGROUND: The aim was to describe the introduction and operation of a virtual developmental dysplasia of the hip (DDH) clinic. Our secondary objectives were to provide an overview of DDH referral reasons, treatment outcomes, and adverse events associated with it. METHODS: A prospective observational study involving all patients referred to the virtual DDH clinic was conducted. The clinic consultant delivered with 2 DDH clinical nurse specialists (CNS). The outcomes following virtual review include further virtual review, CNS review, consultant review or discharge. Treatment options include surveillance, brace therapy, or surgery. Efficiency and cost analysis were assessed. RESULTS: Over the 3.5-year study period, 1002 patients were reviewed, of which 743 (74.2%) were female. The median age at time of referral was 7 months, (interquartile range of 5 to 11) with a median time to treatment decision of 9 days. Median waiting times from referral to treatment decision was reduced by over 70%. There were 639 virtual reviews, 186 CNS reviews, and 144 consultant reviews. The direct discharge rate was 24%. One hundred one patients (10%) had dislocated or subluxed hips at initial visit while 26.3% had radiographically normal hips. Over the study period 704 face to face (F2F) visits were avoided. Cost reductions of 170 were achieved per patient, with 588,804 achieved in total. Eighteen parents (1.8%) opted for F2F instead of virtual review. There were no unscheduled rereferrals or recorded adverse events. CONCLUSION: We report the outcomes of the first prospective virtual DDH clinic. This clinic has demonstrated efficiency and cost-effectiveness, without reported adverse outcomes to date. It is an option to provide consultant delivered DDH care, while reducing F2F consults. LEVEL OF EVIDENCE: Level III.
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Atención Ambulatoria/métodos , Luxación Congénita de la Cadera/diagnóstico por imagen , Luxación Congénita de la Cadera/terapia , Telemedicina/estadística & datos numéricos , Atención Ambulatoria/economía , Atención Ambulatoria/organización & administración , Tirantes , Ahorro de Costo/estadística & datos numéricos , Femenino , Costos de la Atención en Salud/estadística & datos numéricos , Humanos , Lactante , Masculino , Enfermeras Clínicas/organización & administración , Visita a Consultorio Médico/economía , Visita a Consultorio Médico/estadística & datos numéricos , Alta del Paciente/estadística & datos numéricos , Estudios Prospectivos , Derivación y Consulta/estadística & datos numéricos , Telemedicina/economía , Telemedicina/organización & administración , Tiempo de Tratamiento , Resultado del Tratamiento , Espera VigilanteRESUMEN
KEY POINTS: TRESK background K+ channel is expressed in sensory neurons and acts as a brake to reduce neuronal activation. Deletion of the channel enhances the excitability of nociceptors. Skin nociceptive C-fibres show an enhanced activation by cold and mechanical stimulation in TRESK knockout animals. Channel deletion selectively enhances mechanical and cold sensitivity in mice, without altering sensitivity to heat. These results indicate that the channel regulates the excitability of specific neuronal subpopulations involved in mechanosensitivity and cold-sensing. ABSTRACT: Background potassium-permeable ion channels play a critical role in tuning the excitability of nociceptors, yet the precise role played by different subsets of channels is not fully understood. Decreases in TRESK (TWIK-related spinal cord K+ channel) expression/function enhance excitability of sensory neurons, but its role in somatosensory perception and nociception is poorly understood. Here, we used a TRESK knockout (KO) mouse to address these questions. We show that TRESK regulates the sensitivity of sensory neurons in a modality-specific manner, contributing to mechanical and cold sensitivity but without any effect on heat sensitivity. Nociceptive neurons isolated from TRESK KO mice show a decreased threshold for activation and skin nociceptive C-fibres show an enhanced activation by cold and mechanical stimulation that was also observed in behavioural tests in vivo. TRESK is also involved in osmotic pain and in early phases of formalin-induced inflammatory pain, but not in the development of mechanical and heat hyperalgesia during chronic pain. In contrast, mice lacking TRESK present cold allodynia that is not further enhanced by oxaliplatin. In summary, genetic removal of TRESK uncovers enhanced mechanical and cold sensitivity, indicating that the channel regulates the excitability of specific neuronal subpopulations involved in mechanosensitivity and cold-sensing, acting as a brake to prevent activation by innocuous stimuli.
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Nociceptores , Canales de Potasio , Animales , Hiperalgesia/genética , Ratones , Nocicepción , Células Receptoras SensorialesRESUMEN
Extracellular pH variations are seen as the principal endogenous signal that triggers activation of Acid-Sensing Ion Channels (ASICs), which are basically considered as proton sensors, and are involved in various processes associated with tissue acidification. Here, we show that human painful inflammatory exudates, displaying non-acidic pH, induce a slow constitutive activation of human ASIC3 channels. This effect is largely driven by lipids, and we identify lysophosphatidylcholine (LPC) and arachidonic acid (AA) as endogenous activators of ASIC3 in the absence of any extracellular acidification. The combination of LPC and AA evokes robust depolarizing current in DRG neurons at physiological pH 7.4, increases nociceptive C-fiber firing, and induces pain behavior in rats, effects that are all prevented by ASIC3 blockers. Lipid-induced pain is also significantly reduced in ASIC3 knockout mice. These findings open new perspectives on the roles of ASIC3 in the absence of tissue pH variation, as well as on the contribution of those channels to lipid-mediated signaling.
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Canales Iónicos Sensibles al Ácido/biosíntesis , Ácido Araquidónico/metabolismo , Lisofosfatidilcolinas/metabolismo , Nociceptores/fisiología , Animales , Línea Celular , Ganglios Espinales/citología , Humanos , Ratones Noqueados , Dolor , RatasRESUMEN
Cold temperature detection involves the process of sensory transduction in cutaneous primary sensory nerve terminals, which converts thermal stimuli into depolarizations of the membrane. This transformation into electrical signals is followed by the subsequent propagation of action potentials in cold-sensitive afferent nerve fibers. A large array of ion channels shapes this process; however, the precise contribution of specific ion channel subtypes to cold perception and cold pain remains elusive. This review aims at giving an update on our current understanding of the role played by TRPs, leak K+ and voltage-gated Na+ and K+ channels in the transduction of cold by nociceptors and in cold-induced pain.
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Frío , Canales Iónicos/metabolismo , Nociceptores/fisiología , Percepción del Dolor/fisiología , Dolor/fisiopatología , Sensación Térmica/fisiología , Animales , Medicina Basada en la Evidencia , Humanos , Activación del Canal Iónico/fisiología , Plasticidad Neuronal/fisiologíaRESUMEN
BACKGROUND: After successful hematopoietic stem cell transplantation, maintaining function and mobility have become key goals in the management of patients with Hurler syndrome, (mucopolysaccharoidosis type 1H). The aim of this study was to establish the functional and radiologic outcomes after hip surgery in patients with this condition who had reached skeletal maturity. METHODS: We prospectively followed 13 mucopolysaccharoidosis type 1H patients with closed triradiate cartilages who had undergone hip surgery in a single institution (Our Lady's Children's Hospital, Crumlin) in early childhood, after successful hematopoietic stem cell transplantation. Functional assessment was performed using the Harris Hip Score. Acetabular and femoral head morphology were defined using a pelvic radiograph. RESULTS: The average age at follow-up was 18.6 years (range, 13.2 to 23.8 y). The average length of follow-up from surgical intervention was 14.6 years (range, 10.3 to 21.6 y). The average Harris Hip Score at follow-up was 61.0 (range, 19 to 91). At follow-up, 4 patients were either wheelchair bound or required a walking frame to mobilize in the community. At follow-up, all hips were in-joint with an average center edge angle of 37.7 degrees (range, 0 to 63 degrees). All hips displayed characteristic medial flattening of the femoral head. Ten hips (of 26 hips) showed radiologic degenerative changes with loss of joint space <2 mm. CONCLUSIONS: Despite the surgical provision of stable well-covered hips, active intervention did not prevent the development of radiologic deterioration and clinically significant hip arthritis. We recommend that pediatric hip surgery in Hurler syndrome be designed with the possibility of early hip replacement in mind. LEVEL OF EVIDENCE: Level III.
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Artroplastia de Reemplazo de Cadera , Predicción , Luxación de la Cadera/cirugía , Articulación de la Cadera/cirugía , Mucopolisacaridosis I/complicaciones , Rango del Movimiento Articular/fisiología , Adolescente , Niño , Preescolar , Femenino , Luxación de la Cadera/diagnóstico por imagen , Luxación de la Cadera/etiología , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/fisiopatología , Humanos , Lactante , Masculino , Estudios Prospectivos , Radiografía , Resultado del TratamientoRESUMEN
In rodent sensory neurons, acid-sensing ion channel 3 (ASIC3) has recently emerged as a particularly important sensor of nonadaptive pain associated with tissue acidosis. However, little is known about the human ASIC3 channel, which includes three splice variants differing in their C-terminal domain (hASIC3a, hASIC3b, and hASIC3c). hASIC3a transcripts represent the main mRNAs expressed in both peripheral and central neuronal tissues (dorsal root ganglia [DRG], spinal cord, and brain), where a small proportion of hASIC3c transcripts is also detected. We show that hASIC3 channels (hASIC3a, hASIC3b, or hASIC3c) are able to directly sense extracellular pH changes not only during acidification (up to pH 5.0), but also during alkalization (up to pH 8.0), an original and inducible property yet unknown. When the external pH decreases, hASIC3 display a transient acid mode with brief activation that is relevant to the classical ASIC currents, as previously described. On the other hand, an external pH increase activates a sustained alkaline mode leading to a constitutive activity at resting pH. Both modes are inhibited by the APETx2 toxin, an ASIC3-type channel inhibitor. The alkaline sensitivity of hASIC3 is an intrinsic property of the channel, which is supported by the extracellular loop and involves two arginines (R68 and R83) only present in the human clone. hASIC3 is thus able to sense the extracellular pH in both directions and therefore to dynamically adapt its activity between pH 5.0 and 8.0, a property likely to participate in the fine tuning of neuronal membrane potential and to neuron sensitization in various pH environments.
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Líquido Extracelular/química , Potenciales de la Membrana/fisiología , Neuronas/fisiología , Canales de Sodio/metabolismo , Canales Iónicos Sensibles al Ácido , Animales , Células COS , Chlorocebus aethiops , Fluorescencia , Humanos , Concentración de Iones de Hidrógeno , Neuronas/metabolismo , Técnicas de Placa-ClampRESUMEN
ABSTRACT: Lipid-rich diet is the major cause of obesity, affecting 13% of the worldwide adult population. Obesity is a major risk factor for metabolic syndrome that includes hyperlipidemia and diabetes mellitus. The early phases of metabolic syndrome are often associated with hyperexcitability of peripheral small diameter sensory fibers and painful diabetic neuropathy. Here, we investigated the effect of high-fat diet-induced obesity on the activity of dorsal root ganglion (DRG) sensory neurons and pain perception. We deciphered the underlying cellular mechanisms involving the acid-sensing ion channel 3 (ASIC3). We show that mice made obese through consuming high-fat diet developed the metabolic syndrome and prediabetes that was associated with heat pain hypersensitivity, whereas mechanical sensitivity was not affected. Concurrently, the slow conducting C fibers in the skin of obese mice showed increased activity on heating, whereas their mechanosensitivity was not altered. Although ASIC3 knockout mice fed with high-fat diet became obese, and showed signs of metabolic syndrome and prediabetes, genetic deletion, and in vivo pharmacological inhibition of ASIC3, protected mice from obesity-induced thermal hypersensitivity. We then deciphered the mechanisms involved in the heat hypersensitivity of mice and found that serum from high-fat diet-fed mice was enriched in lysophosphatidylcholine (LPC16:0, LPC18:0, and LPC18:1). These enriched lipid species directly increased the activity of DRG neurons through activating the lipid sensitive ASIC3 channel. Our results identify ASIC3 channel in DRG neurons and circulating lipid species as a mechanism contributing to the hyperexcitability of nociceptive neurons that can cause pain associated with lipid-rich diet consumption and obesity.
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Síndrome Metabólico , Estado Prediabético , Animales , Ratones , Canales Iónicos Sensibles al Ácido/metabolismo , Dieta Alta en Grasa/efectos adversos , Ganglios Espinales/metabolismo , Lípidos , Síndrome Metabólico/metabolismo , Obesidad , Dolor , Estado Prediabético/metabolismo , Células Receptoras Sensoriales/metabolismoRESUMEN
The sensation of cold or heat depends on the activation of specific nerve endings in the skin. This involves heat- and cold-sensitive excitatory transient receptor potential (TRP) channels. However, we show here that the mechano-gated and highly temperature-sensitive potassium channels of the TREK/TRAAK family, which normally work as silencers of the excitatory channels, are also implicated. They are important for the definition of temperature thresholds and temperature ranges in which excitation of nociceptor takes place and for the intensity of excitation when it occurs. They are expressed with thermo-TRP channels in sensory neurons. TRAAK and TREK-1 channels control pain produced by mechanical stimulation and both heat and cold pain perception in mice. Expression of TRAAK alone or in association with TREK-1 controls heat responses of both capsaicin-sensitive and capsaicin-insensitive sensory neurons. Together TREK-1 and TRAAK channels are important regulators of nociceptor activation by cold, particularly in the nociceptor population that is not activated by menthol.
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Frío , Calor , Canales de Potasio de Dominio Poro en Tándem/fisiología , Canales de Potasio/fisiología , Sensación Térmica/fisiología , Animales , Células Cultivadas , Electrofisiología , Ganglios Espinales/citología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Dolor , Canales de Potasio/genética , Canales de Potasio de Dominio Poro en Tándem/genética , Células Receptoras Sensoriales/citología , Células Receptoras Sensoriales/metabolismo , Sensación Térmica/genéticaRESUMEN
Iatrogenic pain consecutive to a large number of surgical procedures has become a growing health concern. The etiology and pathophysiology of postoperative pain are still poorly understood, but hydrogen ions appear to be important in this process. We have investigated the role of peripheral acid-sensing ion channels (ASICs), which form depolarizing channels activated by extracellular protons, in a rat model of postoperative pain (i.e., hindpaw skin/muscle incision). We report high levels of ASIC-type currents (â¼ 77%) in sensory neurons innervating the hindpaw muscles, with a prevalence of ASIC3-like currents. The ASIC3 protein is largely expressed in lumbar DRG neurons innervating the plantar muscle, and its mRNA and protein levels are increased by plantar incision 24 h after surgery. Pharmacological inhibition of ASIC3 channels with the specific toxin APETx2 or in vivo knockdown of ASIC3 subunit by small interfering RNA led to a significant reduction of postoperative spontaneous, thermal, and postural pain behaviors (spontaneous flinching, heat hyperalgesia, and weight bearing). ASIC3 appears to have an important role in deep tissue but also affects prolonged pain evoked by skin incision alone. The specific homomeric ASIC1a blocker PcTx1 has no effect on spontaneous flinching, when applied peripherally. Together, these data demonstrate a significant role for peripheral ASIC3-containing channels in postoperative pain.
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Hiperalgesia/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Dolor Postoperatorio/metabolismo , Células Receptoras Sensoriales/fisiología , Canales de Sodio/metabolismo , Canales Iónicos Sensibles al Ácido , Animales , Electrofisiología , Ganglios Espinales/metabolismo , Ganglios Espinales/fisiopatología , Miembro Posterior/inervación , Miembro Posterior/metabolismo , Hiperalgesia/fisiopatología , Masculino , Músculo Esquelético/inervación , Músculo Esquelético/metabolismo , Dimensión del Dolor , Dolor Postoperatorio/fisiopatología , ARN Interferente Pequeño , Ratas , Ratas Wistar , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Acid-sensing ion channels (ASICs) are cationic channels activated by extracellular acidosis that are expressed in both central and peripheral nervous systems. Although peripheral ASICs seem to be natural sensors of acidic pain (e.g., in inflammation, ischaemia, lesions or tumours), a direct demonstration is still lacking. We show that approximately 60% of rat cutaneous sensory neurons express ASIC3-like currents. Native as well as recombinant ASIC3 respond synergistically to three different inflammatory signals that are slight acidifications (approximately pH 7.0), hypertonicity and arachidonic acid (AA). Moderate pH, alone or in combination with hypertonicity and AA, increases nociceptors excitability and produces pain suppressed by the toxin APETx2, a specific blocker of ASIC3. Both APETx2 and the in vivo knockdown of ASIC3 with a specific siRNA also have potent analgesic effects against primary inflammation-induced hyperalgesia in rat. Peripheral ASIC3 channels are thus essential sensors of acidic pain and integrators of molecular signals produced during inflammation where they contribute to primary hyperalgesia.
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Inflamación/fisiopatología , Proteínas del Tejido Nervioso/metabolismo , Dolor/metabolismo , Canales de Sodio/metabolismo , Canales Iónicos Sensibles al Ácido , Acidosis/metabolismo , Potenciales de Acción/fisiología , Animales , Ácido Araquidónico/farmacología , Células Cultivadas , Venenos de Cnidarios/metabolismo , Ganglios Espinales/citología , Calor/efectos adversos , Humanos , Soluciones Hipertónicas , Inflamación/metabolismo , Masculino , Proteínas del Tejido Nervioso/genética , Neuronas Aferentes/citología , Neuronas Aferentes/metabolismo , Dimensión del Dolor , Péptidos , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Ratas , Ratas Wistar , Piel/efectos de los fármacos , Piel/inervación , Canales de Sodio/genética , Venenos de Araña/metabolismoRESUMEN
BACKGROUND: The Ponseti method has revolutionized the management of idiopathic congenital talipes equinovarus (CTEV). However, nonidiopathic CTEV is still often primarily treated by extensive surgical soft tissue release. We believe that nonoperative treatment of these patients using the Ponseti method may give very satisfactory results. METHODS: We examined the demographics of nonidiopathic CTEV and the success of the Ponseti method in this population over a 5-year period. We treated 29 patients with 43 nonidiopathic and 97 patients with 138 idiopathic CTEV feet. Patients with nonidiopathic CTEV made up 23% of all cases. The commonest etiologies were arthrogryposis (5 cases), trisomy 21 (4 cases), and spina bifida (3 cases). Average follow-up was 39 (nonidiopathic group) and 35 months (idiopathic group). RESULTS: The Ponseti method was initially successful in 91% of nonidiopathic and 98% of idiopathic feet. Recurrence of deformity occurred in 44% of nonidiopathic and 8% of idiopathic feet. Thirty-seven percent of nonidiopathic feet required extensive surgical release compared with 2% in the idiopathic group. CONCLUSIONS: Although the success rate of the Ponseti method in nonidiopathic CTEV is inferior to that in idiopathic CTEV, 63% of our nonidiopathic patients did not require extensive surgery. We believe that the Ponseti method should be used in all cases of nonidiopathic CTEV. LEVEL OF EVIDENCE: Level III--prospective cohort study.
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Moldes Quirúrgicos , Pie Equinovaro/cirugía , Pie Equinovaro/etiología , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Estudios Prospectivos , Recurrencia , Resultado del TratamientoRESUMEN
The use of hippocampal dissociated neuronal cultures has enabled the study of molecular changes in endogenous native proteins associated with long-term potentiation. Using immunofluorescence labelling of the active (Thr286-phosphorylated) alpha-Ca(2+) /calmodulin-dependent protein kinase II (CaMKII) we found that CaMKII activity was increased by transient (3 × 1 s) depolarisation in 18- to 21-day-old cultures but not in 9- to 11-day-old cultures. The increase in Thr286 phosphorylation of CaMKII required the activation of NMDA receptors and was greatly attenuated by the CaMKII inhibitor KN-62. We compared the effects of transient depolarisation on the surface expression of GluA1 and GluA2 subunits of the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate receptor and found a preferential recruitment of the GluA1 subunit. CaMKII inhibition prevented this NMDA receptor-dependent delivery of GluA1 to the cell surface. CaMKII activation is therefore an important factor in the activity-dependent recruitment of native GluA1 subunit-containing alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate receptors to the cell surface of hippocampal neurons.
Asunto(s)
Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/fisiología , Regulación Enzimológica de la Expresión Génica , Hipocampo/metabolismo , Potenciación a Largo Plazo/fisiología , Neuronas/metabolismo , Receptores AMPA/biosíntesis , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/farmacología , Animales , Animales Recién Nacidos , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/antagonistas & inhibidores , Células Cultivadas , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Hipocampo/efectos de los fármacos , Hipocampo/enzimología , Potenciación a Largo Plazo/efectos de los fármacos , Proteínas de la Membrana/biosíntesis , Neuronas/efectos de los fármacos , Neuronas/enzimología , Ratas , Ratas Wistar , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/fisiologíaRESUMEN
Traumatic hip dislocation in the pediatric patient requires much less energy than in an adult, yet it remains a rare diagnosis. We report the case of a 3-year-old girl who dislocated her right hip when bindings failed to release as she skied downhill. The hip was promptly reduced in the nearest trauma center, and at 18 months after injury, there is no evidence of avascular necrosis. The potential risk of avascular necrosis is significant, and the risk rises greatly when reduction is delayed beyond 6 hours. Reduction can be safely performed in the emergency department, although up to 25% of cases will require open reduction in the operating room. A high index of suspicion is warranted to not miss the "golden window" and achieve satisfactory reduction in a timely fashion.
Asunto(s)
Luxación de la Cadera/etiología , Esquí/lesiones , Factores de Edad , Preescolar , Diagnóstico Precoz , Urgencias Médicas , Femenino , Necrosis de la Cabeza Femoral/prevención & control , Luxación de la Cadera/diagnóstico , Luxación de la Cadera/diagnóstico por imagen , Luxación de la Cadera/cirugía , Humanos , Radiografía , Estrés MecánicoRESUMEN
Colorectal cancer (CRC) continues to be one of the most common cancers globally. The incidence has increased in developing countries in the past few decades, this could be partly attributed to aging populations and unhealthy lifestyles. While the treatment of CRC has seen significant improvement since the advent of target-specific therapies and personalized medicine, CRC is oftentimes detected at late or advanced stages, thereby reducing the efficacy of treatment. Hence, screening for early detection is still the key to combat CRC and to increase overall survival (OS). Considering that the field of medical diagnostics is moving towards molecular diagnostics, CRC can now be effectively screened and diagnosed with high accuracy and sensitivity. Depending on the tumor genotype and genetic profile of the individual, personalized treatments including tyrosine kinase inhibitor therapy and immunotherapy can be administered. Notably, there can be no one single treatment that is effective for all CRC patients due to the variation in tumor genetics, which highlights the importance of molecular diagnostics. This review provides insights on therapeutic modalities, molecular biomarkers, advancement of diagnostic technologies, and current challenges in managing CRC.
RESUMEN
Acquired immunodeficiency syndrome (AIDS) cases are on the rise globally. To date, there is still no effective measure to eradicate the causative agent, human immunodeficiency virus (HIV). Highly active antiretroviral therapy (HAART) is being used in HIV/AIDS management, but it results in long-term medication and has major drawbacks such as multiple side effects, high cost, and increasing the generation rate of escape mutants. In addition, HAART does not control HIV-related complications, and hence more medications and further management are required. With this, other alternatives are urgently needed. In the past, small-molecule inhibitors have shown potent antiviral effects, and some of them are now being evaluated in clinical trials. The challenges in developing these small molecules for clinical use include the off-target effect, poor stability, and low bioavailability. On the other hand, antibody-mediated therapy has emerged as an important therapeutic modality for anti-HIV therapeutics development. Many antiviral antibodies, namely, broad neutralizing antibodies (bnAbs) against multiple strains of HIV, have shown promising effects in vitro and in animal studies; further studies are ongoing in clinical trials to evaluate their uses in clinical applications. This short review aims to discuss the current development of therapeutic antibodies against HIV and the challenges in adopting them for clinical use.