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1.
World J Orthop ; 13(2): 171-177, 2022 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-35317399

RESUMEN

BACKGROUND: Carpal tunnel syndrome (CTS) is one of the most common peripheral nerve compressive neuropathies. The clinical symptoms and physical examinations of CTS are widely recognised, however, there is still debate around what is the best approach for assessment of CTS. Clinical assessment is still considered the gold standard, however, controversies do exist regarding the need for investigations such nerve conduction studies (NCS) to aid with management decisions. AIM: To correlate the severity of NCS results to a scoring system which included symptoms, signs and risk factors. METHODS: This was a prospective correlation study. We scored patients' signs and symptoms using our CTS scoring system. This was then correlated with the findings of the NCS. The scoring system included - four symptoms (2 Katz hand diagrams - one for tingling and one for numbness; nocturnal paresthesia and bilateral symptoms) and four clinical signs (weak thumb abduction test; Tinel's sign; Phalen sign and hypoalgesia in median nerve territory) and two risk factors (age more than 40 years and female sex). We classified the NCS results to normal, mild, moderate and severe. RESULTS: There were 61 scores in 59 patients. The mean scores for the categories were as follows: 6.75 for normal NCS; 5.50 for mild NCS; 9.17 for moderate NCS and 9 for severe NCS. All scores of 8 or more matched with NCS results of moderate and severe intensity apart from three scores which were greater than seven that had normal NCS. Eta score was 0.822 for the CTS score being the dependent value and the NCS category being the independent variable showing a strong association between the scoring system and the NCS group. CONCLUSION: We feel that this simple scoring system can be used to predict and correlate the severity of NCS in patients with CTS.

2.
Ultrasound Med Biol ; 48(6): 1019-1032, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35307235

RESUMEN

Ultrasound has previously been demonstrated to non-invasively cause tissue disruption. Small animal studies have demonstrated that this effect can be enhanced by contrast microbubbles and has the potential to be clinically beneficial in techniques such as targeted drug delivery or enhancing liquid biopsies when a physical biopsy may be inappropriate. Cavitating microbubbles in close proximity to cells increases membrane permeability, allowing small intracellular molecules to leak into the extracellular space. This study sought to establish whether cavitating microbubbles could liberate cell-specific miRNAs, augmenting biomarker detection for non-invasive liquid biopsies. Insonating human polarized renal proximal tubular epithelial cells (RPTECs), in the presence of SonoVue microbubbles, revealed that cellular health could be maintained while achieving the release of miRNAs, miR-21, miR-30e, miR-192 and miR-194 (respectively, 10.9-fold, 7.17-fold, 5.95-fold and 5.36-fold). To examine the mechanism of release, RPTECs expressing enhanced green fluorescent protein were generated and the protein successfully liberated. Cell polarization, cellular phenotype and cell viability after sonoporation were measured by a number of techniques. Ultrastructural studies using electron microscopy showed gap-junction disruption and pore formation on cellular surfaces. These studies revealed that cell-specific miRNAs can be non-specifically liberated from RPTECs by sonoporation without a significant decrease in cell viability.


Asunto(s)
MicroARNs , Animales , Biomarcadores , Permeabilidad de la Membrana Celular , Células Epiteliales , Humanos , Microburbujas
3.
Ageing Res Rev ; 71: 101447, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34403830

RESUMEN

Deficits in adult neurogenesis may contribute to the aetiology of many neurodevelopmental, psychiatric and neurodegenerative diseases. Genetic ablation of neurogenesis provides proof of concept that adult neurogenesis is required to sustain complex and dynamic cognitive functions, such as learning and memory, mostly by providing a high degree of plasticity to neuronal circuits. In addition, adult neurogenesis is reactive to external stimuli and the environment making it particularly susceptible to impairment and consequently contributing to comorbidity. In the human brain, the dentate gyrus of the hippocampus is the main active source of neural stem cells that generate granule neurons throughout life. The regulation and preservation of the pool of neural stem cells is central to ensure continuous and healthy adult hippocampal neurogenesis (AHN). Recent advances in genetic and metabolic profiling alongside development of more predictive animal models have contributed to the development of new concepts and the emergence of molecular mechanisms that could pave the way to the implementation of new therapeutic strategies to treat neurological diseases. In this review, we discuss emerging molecular mechanisms underlying AHN that could be embraced in drug discovery to generate novel concepts and targets to treat diseases of ageing including neurodegeneration. To support this, we review cellular and molecular mechanisms that have recently been identified to assess how AHN is sustained throughout life and how AHN is associated with diseases. We also provide an outlook on strategies for developing correlated biomarkers that may accelerate the translation of pre-clinical and clinical data and review clinical trials for which modulation of AHN is part of the therapeutic strategy.


Asunto(s)
Células-Madre Neurales , Neurogénesis , Envejecimiento , Animales , Hipocampo , Humanos , Neuronas
4.
JCI Insight ; 5(24)2020 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-33328386

RESUMEN

Small noncoding RNAs, miRNAs (miRNAs), are emerging as important modulators in the pathogenesis of kidney disease, with potential as biomarkers of kidney disease onset, progression, or therapeutic efficacy. Bulk tissue small RNA-sequencing (sRNA-Seq) and microarrays are widely used to identify dysregulated miRNA expression but are limited by the lack of precision regarding the cellular origin of the miRNA. In this study, we performed cell-specific sRNA-Seq on tubular cells, endothelial cells, PDGFR-ß+ cells, and macrophages isolated from injured and repairing kidneys in the murine reversible unilateral ureteric obstruction model. We devised an unbiased bioinformatics pipeline to define the miRNA enrichment within these cell populations, constructing a miRNA catalog of injury and repair. Our analysis revealed that a significant proportion of cell-specific miRNAs in healthy animals were no longer specific following injury. We then applied this knowledge of the relative cell specificity of miRNAs to deconvolute bulk miRNA expression profiles in the renal cortex in murine models and human kidney disease. Finally, we used our data-driven approach to rationally select macrophage-enriched miR-16-5p and miR-18a-5p and demonstrate that they are promising urinary biomarkers of acute kidney injury in renal transplant recipients.


Asunto(s)
Lesión Renal Aguda/genética , MicroARNs/genética , Especificidad de Órganos/genética , Animales , Biomarcadores , Biología Computacional/métodos , Células Endoteliales/metabolismo , Perfilación de la Expresión Génica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Riñón/metabolismo , Túbulos Renales/metabolismo , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/metabolismo
5.
Front Immunol ; 10: 2547, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31749806

RESUMEN

Background: Ultrasound guided sampling of human lymph node (LN) combined with advanced flow cytometry allows phenotypic analysis of multiple immune cell subsets. These may provide insights into immune processes and responses to immunotherapies not apparent from analysis of the blood. Methods: Ultrasound guided inguinal LN samples were obtained by both fine needle aspiration (FNA) and core needle biopsy in 10 adults within 8 weeks of diagnosis of type 1 diabetes (T1D) and 12 age-matched healthy controls at two study centers. Peripheral blood mononuclear cells (PBMC) were obtained on the same occasion. Samples were transported same day to the central laboratory and analyzed by multicolour flow cytometry. Results: LN sampling was well-tolerated and yielded sufficient cells for analysis in 95% of cases. We confirmed the segregation of CD69+ cells into LN and the predominance of CD8+ Temra cells in blood previously reported. In addition, we demonstrated clear enrichment of CD8+ naïve, FOXP3+ Treg, class-switched B cells, CD56bright NK cells and plasmacytoid dendritic cells (DC) in LNs as well as CD4+ T cells of the Th2 phenotype and those expressing Helios and Ki67. Conventional NK cells were virtually absent from LNs as were Th22 and Th1Th17 cells. Paired correlation analysis of blood and LN in the same individuals indicated that for many cell subsets, especially those associated with activation: such as CD25+ and proliferating (Ki67+) T cells, activated follicular helper T cells and class-switched B cells, levels in the LN compartment could not be predicted by analysis of blood. We also observed an increase in Th1-like Treg and less proliferating (Ki67+) CD4+ T cells in LN from T1D compared to control LNs, changes which were not reflected in the blood. Conclusions: LN sampling in humans is well-tolerated. We provide the first detailed "roadmap" comparing immune subsets in LN vs. blood emphasizing a role for differentiated effector T cells in the blood and T cell regulation, B cell activation and memory in the LN. For many subsets, frequencies in blood, did not correlate with LN, suggesting that LN sampling would be valuable for monitoring immuno-therapies where these subsets may be impacted.


Asunto(s)
Diabetes Mellitus Tipo 1/inmunología , Citometría de Flujo , Ganglios Linfáticos/inmunología , Linfocitos/inmunología , Adulto , Diabetes Mellitus Tipo 1/patología , Femenino , Humanos , Ganglios Linfáticos/patología , Linfocitos/patología , Masculino
6.
PLoS One ; 10(8): e0127785, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26252954

RESUMEN

The cystine-glutamate antiporter (system xc-) is a Na+-independent amino acid transporter that exchanges extracellular cystine for intracellular glutamate. It is thought to play a critical role in cellular redox processes through regulation of intracellular glutathione synthesis via cystine uptake. In gliomas, system xc- expression is universally up-regulated while that of glutamate transporters down-regulated, leading to a progressive accumulation of extracellular glutamate and excitotoxic cell death of the surrounding non-tumorous tissue. Additionally, up-regulation of system xc- in activated microglia has been implicated in the pathogenesis of several neurodegenerative disorders mediated by excess glutamate. Consequently, system xc- is a new drug target for brain cancer and neuroinflammatory diseases associated with excess extracellular glutamate. Unfortunately no potent and selective small molecule system xc- inhibitors exist and to our knowledge, no high throughput screening (HTS) assay has been developed to identify new scaffolds for inhibitor design. To develop such an assay, various neuronal and non-neuronal human cells were evaluated as sources of system xc-. Human glioma cells were chosen based on their high system xc- activity. Using these cells, [14C]-cystine uptake and cystine-induced glutamate release assays were characterized and optimized with respect to cystine and protein concentrations and time of incubation. A pilot screen of the LOPAC/NINDS libraries using glutamate release demonstrated that the logistics of the assay were in place but unfortunately, did not yield meaningful pharmacophores. A larger, HTS campaign using the 384-well cystine-induced glutamate release as primary assay and the 96-well 14C-cystine uptake as confirmatory assay is currently underway. Unexpectedly, we observed that the rate of cystine uptake was significantly faster than the rate of glutamate release in human glioma cells. This was in contrast to the same rates of cystine uptake and glutamate release previously reported in normal human fibroblast cells.


Asunto(s)
Sistema de Transporte de Aminoácidos y+/metabolismo , Neoplasias Encefálicas/metabolismo , Cistina/metabolismo , Glioma/metabolismo , Ácido Glutámico/metabolismo , Ensayos Analíticos de Alto Rendimiento/métodos , Sistema de Transporte de Aminoácidos y+/genética , Benzoatos/farmacología , Neoplasias Encefálicas/genética , Línea Celular Tumoral , Cistina/farmacología , Bases de Datos de Compuestos Químicos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glioma/genética , Glicina/análogos & derivados , Glicina/farmacología , Humanos , Concentración 50 Inhibidora , Modelos Biológicos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Sulfasalazina/farmacología , Factores de Tiempo
7.
Open Orthop J ; 9: 194-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26069515

RESUMEN

The purpose of this study was to assess whether subsidence occurs in collarless Corail hip replacement (CCHR) and to ascertain the extent and timing of subsidence if present. Retrospective case notes analysis was performed. Sixty eight patients who had CCHR were identified from our database. Male to female ratio was 32:36. Their mean age was 74.2 years (range 37-95 years). Indications for surgery were osteoarthritis in 64 (94%) patients, rheumatoid arthritis in two (3%) patients and avascular necrosis in two (3%) patients. Subsidence was measured at 6 weeks, 6 months and 1 year post-op compared to initial post-op x-rays. At 6 weeks x-ray 21 patients did not have any subsidence, 18 patients had 1 millimeter (mm) subsidence, 10 patients had 2mms subsidence, 4 patients had 3mms subsidence, 5 patients had 4mms subsidence, 1 patient had 5mms subsidence, 4 patients had 6 mms subsidence and 1 patient each had subsidence of 7mms, 9mms, 11mms, 13mms and 26 mms respectively. When compared with 6 months x-rays only 2 patients had a further subsidence of 2mms while another patient had 3mms subsidence. No further subsidence occurred at 1 year follow up x-rays. One patient had revision surgery due to symptomatic subsidence (29mms) at 6 months follow up. Subsidence does occur in the first 6 weeks in collarless Corail hip replacement, and to a lesser extent until 6 months postoperatively, but does not progress further.

8.
Am J Emerg Med ; 26(9): 1073.e1-2, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19091297

RESUMEN

Blood pressure recording is a part of the routine set of initial observations for any patient. It is performed by variety of medical and paramedical personnel universally. Bone metastases and pathologic fracture of the bone are common in the elderly patient. Noninvasive blood pressure recording is innocuous procedure, although on rare occasions can cause iatrogenic fracture of the asymptomatic pathologic bone. This case report highlights the importance of vigilance to look for pain and tender area over the site of blood pressure cuff placement and before its inflation to record blood pressure, as it can be "traumatic" for the asymptomatic weak pathologic bone leading to a fracture. Iatrogenic fracture can add to the burden of a patient's medical problem, necessitating secondary surgical procedure, delaying recovery, and having the possibility of medicolegal problems.


Asunto(s)
Determinación de la Presión Sanguínea/efectos adversos , Fracturas del Fémur/etiología , Fracturas del Hombro/etiología , Accidentes por Caídas , Anciano de 80 o más Años , Femenino , Humanos , Radiografía , Fracturas del Hombro/diagnóstico por imagen , Fracturas del Hombro/patología
9.
J Neurosci ; 26(23): 6364-76, 2006 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-16763045

RESUMEN

We show that desert hedgehog (dhh), a signaling molecule expressed by Schwann cells, is essential for the structural and functional integrity of the peripheral nerve. Dhh-null nerves display multiple abnormalities that affect myelinating and nonmyelinating Schwann cells, axons, and vasculature and immune cells. Myelinated fibers of these mice have a significantly increased (more than two times) number of Schmidt-Lanterman incisures (SLIs), and connexin 29, a molecular component of SLIs, is strongly upregulated. Crossing Dhh-null mice with myelin basic protein (MBP)-deficient shiverer mice, which also have increased SLI numbers, results in further increased SLIs, suggesting that Dhh and MBP control SLIs by different mechanisms. Unmyelinated fibers are also affected, containing many fewer axons per Schwann cell in transverse profiles, whereas the total number of unmyelinated axons is reduced by approximately one-third. In Dhh-null mice, the blood-nerve barrier is permeable and neutrophils and macrophage numbers are elevated, even in uninjured nerves. Dhh-null nerves also lack the largest-diameter myelinated fibers, have elevated numbers of degenerating myelinated axons, and contain regenerating fibers. Transected dhh nerves degenerate faster than wild-type controls. This demonstrates that a single identified glial signal, Dhh, plays a critical role in controlling the integrity of peripheral nervous tissue, in line with its critical role in nerve sheath development (Parmantier et al., 1999). The complexity of the defects raises a number of important questions about the Dhh-dependent cell-cell signaling network in peripheral nerves.


Asunto(s)
Neuroglía/metabolismo , Nervio Ciático/anatomía & histología , Nervio Ciático/fisiología , Transducción de Señal , Transactivadores/fisiología , Envejecimiento/metabolismo , Animales , Animales Recién Nacidos/crecimiento & desarrollo , Animales Recién Nacidos/metabolismo , Axones , Permeabilidad Capilar , Recuento de Células , Tamaño de la Célula , Conexinas/genética , Conexinas/metabolismo , Proteínas Hedgehog , Ratones , Ratones Noqueados , Neuronas Motoras/patología , Vaina de Mielina/patología , Degeneración Nerviosa , Fibras Nerviosas Mielínicas/ultraestructura , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , ARN Mensajero/metabolismo , Células de Schwann/patología , Nervio Ciático/irrigación sanguínea , Nervio Ciático/ultraestructura , Transactivadores/deficiencia , Transactivadores/genética , Transactivadores/metabolismo , Regulación hacia Arriba
10.
Exp Brain Res ; 174(4): 734-45, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16721607

RESUMEN

The variety of sometimes contradictory results of studies of the impact of secondary cognitive tasks on postural balance may be attributed to the heterogeneity of balance challenges and tasks deployed and frequent lack of quantitative comparability of tasks. We deployed a wide range of quantitatively graded difficulties of both balance challenge and cognitive tasking to obtain an overview of the spectrum of their interactions in a multi-tasking situation. A differential comparison of the effects of verbally versus spatially loaded tasks, balanced for difficulty, was made and unlike any other study, we contrived to incorporate falls as an experimental variable. In the first study subjects stood in tandem on beams of either 2, 3 and 6 cm or 3, 6 and 8 cm width (according to 'best performance' ability) while performing mental verbal or spatial 'Stroop' tasks. The design was a between groups (sixteen subjects each) comparison (to reduce learning effect) of sway, fall rate and task error, balanced for order. Measurements were taken of centre of pressure, sway velocity at the hip and head displacement. For any beam width there were no within-subject correlations between sway magnitudes and frequency of falls. Spatial task errors increased with balance challenge (hence with magnitude of sway) but verbal performance was maintained independently of balance challenge. The results of the first study provided statistical power estimates for the design of the second focussed experiment which made a within group (twenty four subjects) comparison of the impact of spatial versus verbal tasks on balancing on the hardest beam. The spatial task significantly elevated the incidence of falls whereas the verbal task had no effect on fall rate. The spatial task raised the incidence of falling by 50% (P = 0.0008) in comparison with 'no task'. The verbal task had no effect (P = 0.07). We conclude that sway magnitude is a poor index of multi-task load. Multi-tasking can increase the chance of falling and spatial processing may have a specific impact on balance. The significant elevation of fall frequency during cognitive tasking shows that the 'posture first' principal can be transgressed although the necessary condition for transgression may be that the subject is willing to take risks believing that he can arrest any fall.


Asunto(s)
Atención , Cognición/fisiología , Movimiento/fisiología , Equilibrio Postural/fisiología , Desempeño Psicomotor/fisiología , Accidentes por Caídas , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Percepción Espacial/fisiología , Análisis y Desempeño de Tareas , Conducta Verbal
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