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1.
J Immunol ; 208(2): 454-463, 2022 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-34930781

RESUMEN

Inflammation involves a delicate balance between pathogen clearance and limiting host tissue damage, and perturbations in this equilibrium promote disease. Patients suffering from autoimmune diseases, such as systemic lupus erythematosus (SLE), have higher levels of serum S100A9 protein and increased risk for infection. S100A9 is highly abundant within neutrophils and modulates antimicrobial activity in response to bacterial pathogens. We reasoned that increased serum S100A9 in SLE patients reflects accumulation of S100A9 protein in neutrophils and may indicate altered neutrophil function. In this study, we demonstrate elevated S100A9 protein within neutrophils from SLE patients, and MRL/lpr mice associates with lower mitochondrial superoxide, decreased suicidal neutrophil extracellular trap formation, and increased susceptibility to Staphylococcus aureus infection. Furthermore, increasing mitochondrial superoxide production restored the antibacterial activity of MRL/lpr neutrophils in response to S. aureus These results demonstrate that accumulation of intracellular S100A9 associates with impaired mitochondrial homeostasis, thereby rendering SLE neutrophils inherently less bactericidal.


Asunto(s)
Calgranulina B/sangre , Trampas Extracelulares/inmunología , Lupus Eritematoso Sistémico/sangre , Lupus Eritematoso Sistémico/inmunología , Mitocondrias/metabolismo , Staphylococcus aureus/inmunología , Animales , Susceptibilidad a Enfermedades/inmunología , Femenino , Homeostasis/fisiología , Humanos , Inflamación/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neutrófilos/inmunología , Infecciones Estafilocócicas/inmunología , Staphylococcus aureus/crecimiento & desarrollo , Superóxidos/metabolismo
2.
Sensors (Basel) ; 24(20)2024 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-39460231

RESUMEN

Low back pain affects 619 million people worldwide and is commonly provoked by sitting. Current assessment methods constrain task variability, removing real-world, task-switching behaviors. This study utilized accelerometers to provide an original validated method of in vivo real-world assessment of lumbar sitting behavior throughout a full day. A three-stage study design was used, which involved (1) blinded verification of our sitting detection algorithm, (2) full-day data collection from participants with low back discomfort, quantifying lumbar angles, and end-user acceptability explored, (3) case study application to two clinical low back pain (LBP) patients, incorporating measurement of provocative sitting. Focus group discussions demonstrated that data collection methods were acceptable. Sitting 'windows' were created and analyzed using novel histograms, amplitude probability distribution functions, and variability, demonstrating that sitting behavior was unique and varied across individuals. One LBP patient demonstrated two frequent lumbar postures (<15% flexion and ~75% flexion), with pain provocation at 62% lumbar flexion. The second patient demonstrated a single dominant posture (~90% flexion), with pain provoked at 86% lumbar flexion. Our in vivo approach offers an acceptable method to gain new insights into provocative sitting behavior in individuals with LBP, allowing individualized unconstrained data for full-day postures and pain provocation behaviors to be quantified, which are otherwise unattainable.


Asunto(s)
Acelerometría , Dolor de la Región Lumbar , Sedestación , Humanos , Dolor de la Región Lumbar/fisiopatología , Masculino , Femenino , Adulto , Acelerometría/métodos , Postura/fisiología , Región Lumbosacra/fisiopatología , Algoritmos , Persona de Mediana Edad
3.
Am J Physiol Gastrointest Liver Physiol ; 323(4): G306-G317, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-35916405

RESUMEN

The alternative (noncanonical) nuclear factor-κB (NF-κB) signaling pathway predominantly regulates the function of the p52/RelB heterodimer. Germline Nfkb2 deficiency in mice leads to loss of p100/p52 protein and offers protection against a variety of gastrointestinal conditions, including azoxymethane/dextran sulfate sodium (DSS)-induced colitis-associated cancer and lipopolysaccharide (LPS)-induced small intestinal epithelial apoptosis. However, the common underlying protective mechanisms have not yet been fully elucidated. We applied high-throughput RNA-Seq and proteomic analyses to characterize the transcriptional and protein signatures of the small intestinal mucosa of naïve adult Nfkb2-/- mice. Those data were validated by immunohistochemistry and quantitative ELISA using both small intestinal tissue lysates and serum. We identified a B-lymphocyte defect as a major transcriptional signature in the small intestinal mucosa and immunoglobulin A as the most downregulated protein by proteomic analysis in Nfkb2-/- mice. Small intestinal immunoglobulins were dramatically dysregulated, with undetectable levels of immunoglobulin A and greatly increased amounts of immunoglobulin M being detected. The numbers of IgA-producing, cluster of differentiation (CD)138-positive plasma cells were also reduced in the lamina propria of the small intestinal villi of Nfkb2-/- mice. This phenotype was even more striking in the small intestinal mucosa of RelB-/- mice, although these mice were equally sensitive to LPS-induced intestinal apoptosis as their RelB+/+ wild-type counterparts. NF-κB2/p52 deficiency confers resistance to LPS-induced small intestinal apoptosis and also appears to regulate the plasma cell population and immunoglobulin levels within the gut.NEW & NOTEWORTHY Novel transcriptomic analysis of murine proximal intestinal mucosa revealed an unexpected B cell signature in Nfkb2-/- mice. In-depth analysis revealed a defect in the CD38+ B cell population and a gut-specific dysregulation of immunoglobulin levels.


Asunto(s)
Subunidad p52 de NF-kappa B , Células Plasmáticas , Animales , Inmunoglobulina A/metabolismo , Inmunoglobulinas/metabolismo , Mucosa Intestinal/metabolismo , Lipopolisacáridos/farmacología , Ratones , FN-kappa B/metabolismo , Subunidad p52 de NF-kappa B/genética , Subunidad p52 de NF-kappa B/metabolismo , Células Plasmáticas/metabolismo , Proteómica
4.
BMC Med Imaging ; 22(1): 5, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34986790

RESUMEN

Pancreas volume is reduced in individuals with diabetes and in autoantibody positive individuals at high risk for developing type 1 diabetes (T1D). Studies investigating pancreas volume are underway to assess pancreas volume in large clinical databases and studies, but manual pancreas annotation is time-consuming and subjective, preventing extension to large studies and databases. This study develops deep learning for automated pancreas volume measurement in individuals with diabetes. A convolutional neural network was trained using manual pancreas annotation on 160 abdominal magnetic resonance imaging (MRI) scans from individuals with T1D, controls, or a combination thereof. Models trained using each cohort were then tested on scans of 25 individuals with T1D. Deep learning and manual segmentations of the pancreas displayed high overlap (Dice coefficient = 0.81) and excellent correlation of pancreas volume measurements (R2 = 0.94). Correlation was highest when training data included individuals both with and without T1D. The pancreas of individuals with T1D can be automatically segmented to measure pancreas volume. This algorithm can be applied to large imaging datasets to quantify the spectrum of human pancreas volume.


Asunto(s)
Aprendizaje Profundo , Diabetes Mellitus Tipo 1/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Páncreas/diagnóstico por imagen , Adolescente , Algoritmos , Diabetes Mellitus Tipo 1/patología , Humanos , Imagenología Tridimensional/métodos , Masculino , Tamaño de los Órganos , Páncreas/patología , Estudios Retrospectivos
5.
Vet Pathol ; 59(2): 299-309, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34872393

RESUMEN

This study was designed to identify the cause of mutilation and death in 32 cats, part of a larger cohort found dead in Greater London, the United Kingdom, between 2016 and 2018. At the time, discussion in the media led to concerns of a human serial cat killer (dubbed The Croydon Cat Killer) pursuing domestic cats, causing a state of disquietude. Given the link between animal abuse and domestic violence, human intervention had to be ruled out. Using a combination of DNA testing, computed tomography imaging, and postmortem examination, no evidence was found to support any human involvement. Instead, a significant association between cat carcass mutilation and the presence of fox DNA was demonstrated. Gross examination identified shared characteristics including the pattern of mutilation, level of limb or vertebral disarticulation, wet fur, wound edges with shortened fur, and smooth or irregular contours, and marks in the skin, muscle, and bone consistent with damage from carnivore teeth. Together these findings supported the theory that the cause of mutilation was postmortem scavenging by red foxes (Vulpes vulpes). The probable cause of death was established in 26/32 (81%) carcasses: 10 were predated, 8 died from cardiorespiratory failure, 6 from blunt force trauma, one from ethylene glycol toxicity, and another from liver failure. In 6 carcasses a cause of death was not established due to autolysis and/or extensive mutilation. In summary, this study highlights the value of a multidisciplinary approach to fully investigate cases of suspected human-inflicted mutilation of animals.


Asunto(s)
Carnívoros , Zorros , Animales , Gatos , Humanos , Reino Unido
6.
FASEB J ; 33(3): 3129-3136, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30359099

RESUMEN

Metabolomics studies have the potential to discover biomarkers. Fecal volatile organic compounds (VOCs) have been found to differ in patients with inflammatory bowel disease and irritable bowel syndrome. Murine models of colitis offer an alternative to human studies in which diet can be controlled. We aimed to investigate fecal VOCs from mice in which acute and chronic colitis was induced. Groups of adult C57BL/6 mice underwent treatment with oral dextran sulfate sodium to induce colitis. Control mice received no treatment or had acute osmotic diarrhea induced with magnesium sulfate. Colitis was assessed clinically and by histology. Samples of feces and/or colon contents were collected and volatile compounds determined by solid phase microextraction-GC-MS. Statistics were performed using metabolomics tools. Acute colitis was associated with an increase in aldehydes and chronic colitis with one specific ketone. Osmotic diarrhea was associated with a significant reduction in VOCs, especially alcohols. We provide evidence that the identification of disease-associated VOC concentration ranges, combined with specific marker compounds, would potentially increase the likelihood of finding an inflammatory bowel disease-specific fecal VOC marker profile.-Reade, S., Williams, J. M., Aggio, R., Duckworth, C. A., Mahalhal, A., Hough, R., Pritchard, D. M., Probert, C. S., Potential role of fecal volatile organic compounds as biomarkers of chemically induced intestinal inflammation in mice.


Asunto(s)
Colitis/metabolismo , Heces/química , Compuestos Orgánicos Volátiles/análisis , Enfermedad Aguda , Aldehídos/análisis , Animales , Biomarcadores/análisis , Enfermedad Crónica , Colitis/inducido químicamente , Colitis/patología , Sulfato de Dextran , Diarrea/inducido químicamente , Diarrea/metabolismo , Modelos Animales de Enfermedad , Femenino , Humanos , Enfermedades Inflamatorias del Intestino/diagnóstico , Enfermedades Inflamatorias del Intestino/metabolismo , Metabolómica , Ratones , Ratones Endogámicos C57BL
7.
J Sport Rehabil ; 28(8)2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30860413

RESUMEN

CONTEXT: Balance is important for injury prediction, prevention, and rehabilitation. Clinical measurement of higher level balance function such as hop landing is necessary. Currently, no method exists to quantify balance performance following hopping in the clinic. OBJECTIVE: To quantify the sacral acceleration profile and test-retest reliability during hop landing. PARTICIPANTS: A total of 17 university undergraduates (age 27.6 [5.7] y, height 1.73 [0.11] m, weight 74.1 [13.9] kg). MAIN OUTCOME MEASURE: A trunk-mounted accelerometer captured the acceleration profile following landing from hopping forward, medially, and laterally. The path length of the acceleration traces were computed to quantify balance following landing. RESULTS: Moderate to excellent reliability (intraclass correlation coefficient .67-.93) for hop landing was established with low to moderate SEM (4%-16%) and minimal detectable change values (13%-44%) for each of the hop directions. Significant differences were determined in balance following hop landing from the different directions. CONCLUSION: The results suggest that hop landing balance can be quantified by trunk-mounted accelerometry.


Asunto(s)
Acelerometría , Movimiento , Equilibrio Postural/fisiología , Torso/fisiología , Adulto , Humanos , Reproducibilidad de los Resultados , Adulto Joven
8.
J Immunol ; 195(3): 853-64, 2015 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-26109644

RESUMEN

Autoreactive B lymphocytes that escape central tolerance and mature in the periphery are a liability for developing autoimmunity. IgG insulin autoantibodies that predict type 1 diabetes and complicate insulin therapies indicate that mechanisms for tolerance to insulin are flawed. To examine peripheral tolerance in anti-insulin B cells, we generated C57BL/6 mice that harbor anti-insulin VDJH-125 site directed to the native IgH locus (VH125(SD)). Class switch-competent anti-insulin B cells fail to produce IgG Abs following T cell-dependent immunization of VH125(SD) mice with heterologous insulin, and they exhibit markedly impaired proliferation to anti-CD40 plus insulin in vitro. In contrast, costimulation with LPS plus insulin drives robust anti-insulin B cell proliferation. Furthermore, VH125(SD) mice produce both IgM and IgG2a anti-insulin Abs following immunization with insulin conjugated to type 1 T cell-independent Brucella abortus ring test Ag (BRT). Anti-insulin B cells undergo clonal expansion in vivo and emerge as IgM(+) and IgM(-) GL7(+)Fas(+) germinal center (GC) B cells following immunization with insulin-BRT, but not BRT alone. Analysis of Igκ genes in VH125(SD) mice immunized with insulin-BRT reveals that anti-insulin Vκ from the preimmune repertoire is selected into GCs. These data demonstrate that class switch-competent anti-insulin B cells remain functionally silent in T cell-dependent immune responses, yet these B cells are vulnerable to reversal of anergy following combined BCR/TLR engagement that promotes Ag-specific GC responses and Ab production. Environmental factors that lead to infection and inflammation could play a critical yet underappreciated role in driving loss of tolerance and promoting autoimmune disease.


Asunto(s)
Autoanticuerpos/inmunología , Linfocitos B/inmunología , Diabetes Mellitus Tipo 1/inmunología , Anticuerpos Insulínicos/inmunología , Insulina/inmunología , Animales , Autoanticuerpos/biosíntesis , Autoinmunidad/inmunología , Antígenos CD40/inmunología , Diabetes Mellitus Tipo 1/genética , Tolerancia Inmunológica/inmunología , Inmunoglobulina G/biosíntesis , Inmunoglobulina G/inmunología , Inmunoglobulina M/biosíntesis , Inmunoglobulina M/inmunología , Lipopolisacáridos , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Datos de Secuencia Molecular , Exones VDJ/inmunología
9.
Biochim Biophys Acta ; 1853(10 Pt A): 2349-60, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26036343

RESUMEN

P21-activated kinases (PAKs) are multifunctional effectors of Rho GTPases with both kinase and scaffolding activity. Here, we investigated the effects of inflammation on PAK1 signaling and its role in colitis-driven carcinogenesis. PAK1 and p-PAK1 (Thr423) were assessed by immunohistochemistry, immunofluorescence, and Western blot. C57BL6/J wildtype mice were treated with a single intraperitoneal TNFα injection. Small intestinal organoids from these mice and from PAK1-KO mice were cultured with TNFα. NF-κB and PPARγ were analyzed upon PAK1 overexpression and silencing for transcriptional/translational regulation. PAK1 expression and activation was increased on the luminal intestinal epithelial surface in inflammatory bowel disease and colitis-associated cancer. PAK1 was phosphorylated upon treatment with IFNγ, IL-1ß, and TNFα. In vivo, mice administered with TNFα showed increased p-PAK1 in intestinal villi, which was associated with nuclear p65 and NF-κB activation. p65 nuclear translocation downstream of TNFα was strongly inhibited in PAK1-KO small intestinal organoids. PAK1 overexpression induced a PAK1-p65 interaction as visualized by co-immunoprecipitation, nuclear translocation, and increased NF-κB transactivation, all of which were impeded by kinase-dead PAK1. Moreover, PAK1 overexpression downregulated PPARγ and mesalamine recovered PPARγ through PAK1 inhibition. On the other hand PAK1 silencing inhibited NF-κB, which was recovered using BADGE, a PPARγ antagonist. Altogether these data demonstrate that PAK1 overexpression and activation in inflammation and colitis-associated cancer promote NF-κB activity via suppression of PPARγ in intestinal epithelial cells.


Asunto(s)
Colitis/metabolismo , Enfermedades Inflamatorias del Intestino/metabolismo , Mucosa Intestinal/metabolismo , FN-kappa B/metabolismo , PPAR gamma/metabolismo , Transducción de Señal , Quinasas p21 Activadas/metabolismo , Animales , Línea Celular , Colitis/genética , Colitis/patología , Humanos , Inflamación/genética , Inflamación/metabolismo , Inflamación/patología , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/patología , Neoplasias Intestinales/genética , Neoplasias Intestinales/metabolismo , Neoplasias Intestinales/patología , Intestinos/patología , Ratones , Ratones Noqueados , FN-kappa B/genética , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , PPAR gamma/genética , Quinasas p21 Activadas/genética
10.
Org Biomol Chem ; 14(36): 8452-8456, 2016 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-27714221

RESUMEN

Air-stable N-sulfonyl and N-phosphonyl DBN hexafluorophosphate salts have been synthesised under mild conditions as sulfonylating and phosphonylating agents. These salts are highly efficient in the sulfonylation and phosphonylation of a range of N- and O-nucleophiles to generate sulfonamides, sulfonate esters, phosphoramidates and phosphonate esters in good yields.

11.
J Pathol ; 236(3): 326-36, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25727407

RESUMEN

NF-κB signalling is an important factor in the development of inflammation-associated cancers. Mouse models of Helicobacter-induced gastric cancer and colitis-associated colorectal cancer have demonstrated that classical NF-κB signalling is an important regulator of these processes. In the stomach, it has also been demonstrated that signalling involving specific NF-κB proteins, including NF-κB1/p50, NF-κB2/p52, and c-Rel, differentially regulate the development of gastric pre-neoplasia. To investigate the effect of NF-κB subunit loss on colitis-associated carcinogenesis, we administered azoxymethane followed by pulsed dextran sodium sulphate to C57BL/6, Nfkb1(-/-), Nfkb2(-/-), and c-Rel(-/-) mice. Animals lacking the c-Rel subunit were more susceptible to colitis-associated cancer than wild-type mice, developing 3.5 times more colonic polyps per animal than wild-type mice. Nfkb2(-/-) mice were resistant to colitis-associated cancer, developing fewer polyps per colon than wild-type mice (median 1 compared to 4). To investigate the mechanisms underlying these trends, azoxymethane and dextran sodium sulphate were administered separately to mice of each genotype. Nfkb2(-/-) mice developed fewer clinical signs of colitis and exhibited less severe colitis and an attenuated cytokine response compared with all other groups following DSS administration. Azoxymethane administration did not fully suppress colonic epithelial mitosis in c-Rel(-/-) mice and less colonic epithelial apoptosis was also observed in this genotype compared to wild-type counterparts. These observations demonstrate different functions of specific NF-κB subunits in this model of colitis-associated carcinogenesis. NF-κB2/p52 is necessary for the development of colitis, whilst c-Rel-mediated signalling regulates colonic epithelial cell turnover following DNA damage.


Asunto(s)
Adenoma/metabolismo , Colitis/complicaciones , Neoplasias del Colon/metabolismo , Subunidad p50 de NF-kappa B/metabolismo , Subunidad p52 de NF-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-rel/metabolismo , Adenoma/inducido químicamente , Adenoma/etiología , Animales , Azoximetano/toxicidad , Transformación Celular Neoplásica/metabolismo , Colitis/inducido químicamente , Neoplasias del Colon/inducido químicamente , Neoplasias del Colon/etiología , Citocinas/metabolismo , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Células Epiteliales/metabolismo , Femenino , Inflamación , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal
12.
J Sports Sci ; 34(11): 1058-66, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26375051

RESUMEN

Artificial surfaces are now an established alternative to grass (natural) surfaces in rugby union. Little is known, however, about their potential to reduce injury. This study characterises the spinal kinematics of rugby union hookers during scrummaging on third-generation synthetic (3G) and natural pitches. The spine was sectioned into five segments, with inertial sensors providing three-dimensional kinematic data sampled at 40 Hz/sensor. Twenty-two adult, male community club and university-level hookers were recruited. An equal number were analysed whilst scrummaging on natural or synthetic turf. Players scrummaging on synthetic turf demonstrated less angular velocity in the lower thoracic spine for right and left lateral bending and right rotation. The general reduction in the range of motion and velocities, extrapolated over a prolonged playing career, may mean that the synthetic turf could result in fewer degenerative injuries. It should be noted, however, that this conclusion considers only the scrummaging scenario.


Asunto(s)
Fútbol Americano/fisiología , Rango del Movimiento Articular , Columna Vertebral/fisiología , Instalaciones Deportivas y Recreativas , Aceleración , Adulto , Traumatismos en Atletas/prevención & control , Fenómenos Biomecánicos , Humanos , Masculino , Poaceae , Rotación , Adulto Joven
13.
J Immunol ; 190(12): 5992-6003, 2013 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-23677466

RESUMEN

Effective central tolerance is required to control the large extent of autoreactivity normally present in the developing B cell repertoire. Insulin-reactive B cells are required for type 1 diabetes in the NOD mouse, because engineered mice lacking this population are protected from disease. The Cg-Tg(Igh-6/Igh-V125)2Jwt/JwtJ (VH125Tg) model is used to define this population, which is found with increased frequency in the periphery of NOD mice versus nonautoimmune C57BL/6 VH125Tg mice; however, the ontogeny of this disparity is unknown. To better understand the origins of these pernicious B cells, anti-insulin B cells were tracked during development in the polyclonal repertoire of VH125Tg mice. An increased proportion of insulin-binding B cells is apparent in NOD mice at the earliest point of Ag commitment in the bone marrow. Two predominant L chains were identified in B cells that bind heterologous insulin. Interestingly, Vκ4-57-1 polymorphisms that confer a CDR3 Pro-Pro motif enhance self-reactivity in VH125Tg/NOD mice. Despite binding circulating autoantigen in vivo, anti-insulin B cells transition from the parenchyma to the sinusoids in the bone marrow of NOD mice and enter the periphery unimpeded. Anti-insulin B cells expand at the site of autoimmune attack in the pancreas and correlate with increased numbers of IFN-γ-producing cells in the repertoire. These data identify the failure to cull autoreactive B cells in the bone marrow as the primary source of anti-insulin B cells in NOD mice and suggest that dysregulation of central tolerance permits their escape into the periphery to promote disease.


Asunto(s)
Autoinmunidad/inmunología , Linfocitos B/inmunología , Células de la Médula Ósea/inmunología , Diabetes Mellitus Tipo 1/inmunología , Islotes Pancreáticos/inmunología , Autotolerancia/inmunología , Secuencia de Aminoácidos , Animales , Autoantígenos/inmunología , Separación Celular , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Región Variable de Inmunoglobulina/química , Región Variable de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/inmunología , Insulina/inmunología , Activación de Linfocitos/inmunología , Ratones , Ratones Endogámicos NOD , Datos de Secuencia Molecular
14.
BMC Musculoskelet Disord ; 16: 105, 2015 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-25935843

RESUMEN

BACKGROUND: Dynamic knee valgus and internal femoral rotation are proposed to be contributory risk factors for patellofemoral pain and anterior cruciate ligament injuries. Multimodal interventions including hip abductor strengthening or functional motor control programmes have a positive impact of pain, however their effect on knee kinematics and muscle strength is less clear. The aim of this study was to examine the effect of isolated hip abductor strengthening and a functional motor control exercise on knee kinematics and hip abductor strength. METHODS: This prospective, randomised, repeated measures design included 29 asymptomatic volunteers presenting with increase knee valgus and femoral internal rotation. Participants completed either isolated hip abductor strengthening or a functional motor control exercise for 5 weeks. Knee kinematics were measured using inertial sensors during 2 functional activities and hip abductor strength measured using a load cell during isometric hip abduction. RESULTS: There were no significant differences in dynamic knee valgus and internal rotation following the isolated hip abductor or functional motor control intervention, and no significant differences between the groups for knee angles. Despite this, the actual magnitude of reduction in valgus was 10° and 5° for the functional motor control group and strengthening group respectively. The actual magnitude of reduction in internal rotation was 9° and 18° for the functional motor control group and strengthening group respectively. Therefore there was a tendency towards clinically significant improvements in knee kinematics in both exercise groups. A statistically significant improvement in hip abductor strength was evident for the functional motor control group (27% increase; p = 0.008) and strengthening group (35% increase; p = 0.009) with no significant difference between the groups being identified (p = 0.475). CONCLUSIONS: Isolated hip strengthening and functional motor control exercises resulted in non-statistically significant changes in knee kinematics, however there was a clear trend towards clinically meaningful reductions in valgus and internal rotation. Both groups demonstrated similar significant gains in hip abductor strength suggesting either approach could be used to strengthen the hip abductors.


Asunto(s)
Terapia por Ejercicio/métodos , Articulación de la Cadera/fisiología , Actividad Motora/fisiología , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Modalidades de Fisioterapia , Adulto , Fenómenos Biomecánicos/fisiología , Femenino , Humanos , Contracción Isométrica/fisiología , Pierna/fisiología , Masculino , Neuronas Motoras/fisiología , Estudios Prospectivos , Rango del Movimiento Articular/fisiología , Reproducibilidad de los Resultados
15.
J Manipulative Physiol Ther ; 38(6): 442-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26099204

RESUMEN

OBJECTIVE: The purpose of this study was to explore the relationship between the kinematic profiles of flexion of the upper lumbar and lower lumbar (LL) spine and hip and 3 sagittally dominant functional tasks (lifting, stand-to-sit, and sit-to-stand). METHODS: Fifty-three participants were recruited for this study. Four sensors were attached to the skin over the S1, L3, T12, and lateral thigh. Relative angles between adjacent sensors were used to quantify the motion for the hip, LL, and upper lumbar spine. Pearson correlation coefficients were used to explore the relationship between the movements and more functional tasks. One-way analysis of variance was used to determine the significance of differences between the variables. RESULTS: Flexion resulted in a greater or similar range of motion (ROM) to the other tasks investigated for both spinal regions but less ROM for the hip. Strong correlations for ROM are reported between forward flexion tasks and lifting for the LL spine (r = 0.83) and all regions during stand-to-sit and sit-to-stand (r = 0.70-0.73). No tasks were strongly correlated for velocity (r = 0.03-0.55). CONCLUSION: Strong correlations were only evident for the LL spine ROM between lifting and flexion; all other tasks afforded moderate or weak correlations. This study suggests that sagittal tasks use different lumbar-hip kinematics and place different demands on the lumbar spine and hip.


Asunto(s)
Fenómenos Biomecánicos/fisiología , Articulación de la Cadera/fisiología , Vértebras Lumbares/fisiología , Rango del Movimiento Articular/fisiología , Adulto , Estudios de Cohortes , Femenino , Voluntarios Sanos , Humanos , Masculino , Postura/fisiología , Análisis y Desempeño de Tareas , Adulto Joven
16.
J Manipulative Physiol Ther ; 38(4): 275-81, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25936464

RESUMEN

OBJECTIVES: The purpose of this study was to investigate the reliability of a novel motion analysis device for measuring the regional breakdown of spinal motion and describing the relative motion of different segments of the thoracolumbar (TL) spine. METHODS: Two protocols were applied to 18 healthy participants. In protocol 1, 2 sensors were placed on the forehead and T1 to measure cervical range of motion (ROM). In protocol 2, 6 sensors were placed on the spinous processes of T1, T4, T8, T12, L3, and S1 to measure TL regional ROM. Intraclass correlation coefficients were used to evaluate the repeatability of movement, whereas SEM was used to define the extent of error. Ranges of motion were demonstrated in flexion extension, right-left lateral flexion, and right-left rotation of the head-cervical, upper thoracic, middle thoracic, lower thoracic, upper lumbar, and lower lumbar. RESULTS: The intraclass correlation coefficient values, for all regions, were found to be high, ranging from 0.88 to 0.99 for all movements, and regions of the spine and SEM values ranged from 0.4° to 5.2°. Multiregional spine ROM ranged from 3° in the upper thoracic and mid-thoracic during flexion and 80° at head cervical during right rotation. CONCLUSION: The described methodology was reliable for assessing regional spinal ROM across multiple spinal regions while providing the relative motions of different segments of the TL spine.


Asunto(s)
Acelerometría/instrumentación , Rango del Movimiento Articular/fisiología , Columna Vertebral/fisiología , Adulto , Humanos , Masculino , Movimiento/fisiología , Reproducibilidad de los Resultados , Procesamiento de Señales Asistido por Computador
17.
BMC Musculoskelet Disord ; 15: 304, 2014 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-25228332

RESUMEN

BACKGROUND: Movement alterations are often reported in individuals with back pain. However the mechanisms behind these movement alterations are not well understood. A commonly cited mechanism is pain. The aim of this study was to investigate the effect of pain reduction, from oral analgesia, on lumbar kinematics in individuals with acute and chronic low back pain. METHODS: A prospective, cross-sectional, experimental repeated-measures design was used. Twenty acute and 20 chronic individuals with low back pain were recruited from General Practitioner and self-referrals to therapy departments for low back pain. Participants complained of movement evoked low back pain. Inertial sensors were attached to the sacrum and lumbar spine and used to measure kinematics. Kinematic variables measured were range of motion, angular velocity and angular acceleration as well as a determining movement irregularity (a measure of deviation from smooth motion). Kinematics were investigated before and after administration of oral analgesia to instigate pain reduction. RESULTS: Pain was significantly reduced following oral analgesia. There were no significant effects on the kinematic variables before and after pain reduction from oral analgesia. There was no interaction between the variables group (acute and chronic) and time (pre and post pain reduction). CONCLUSION: The results demonstrate that pain reduction did not alter lumbar range of motion, angular velocity, angular acceleration or movement irregularity questioning the role of pain in lumbar kinematics.


Asunto(s)
Aceleración , Analgésicos/administración & dosificación , Dolor de la Región Lumbar/tratamiento farmacológico , Región Lumbosacra , Movimiento , Manejo del Dolor/métodos , Rango del Movimiento Articular , Administración Oral , Adulto , Analgesia/métodos , Estudios Transversales , Femenino , Humanos , Dolor de la Región Lumbar/diagnóstico , Masculino , Persona de Mediana Edad , Estudios Prospectivos
18.
J Back Musculoskelet Rehabil ; 37(2): 305-315, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37781790

RESUMEN

BACKGROUND: Despite wobble board use being common in physiotherapy the effect of certain factors, essential to clinical reasoning, have not been investigated. OBJECTIVE: To determine the effect of biological sex, anthropometrics, footwear and dual tasking (DT) on wobble board balance performance. METHODS: Eighty-six healthy participants (44 females) had their wobble board performance measured during double-leg-stance (DLS) with eyes open (DLSEO), closed (DLSEC) and single-leg-stance (SLS) tasks, with and without footwear and a DT added. Anthropometrics were also measured. RESULTS: Females outperformed males during most tasks, with some large effect sizes (ES). Performance was moderately related to weight and shoulder, waist and hip circumference. Overall, there were no differences between footwear and no footwear, except for males during SLS. DT made little difference, except during DLSEO and SLS, where single task was better than DT, though only females had a large ES. CONCLUSION: During wobble board tasks, biological sex differences were observed and a modest correlation between anthropometrics and performance noted. DT and footwear had minimal effect.


Asunto(s)
Equilibrio Postural , Humanos , Masculino , Adulto Joven , Femenino
19.
Med Eng Phys ; 126: 104146, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38621847

RESUMEN

Low back pain (LBP) is a leading cause of disability, resulting in aberrant movement. This movement is difficult to measure accurately in clinical practice and gold standard methods, such as optoelectronic systems involve the use of expensive laboratory equipment. Inertial measurement units (IMU) offer an alternative method of quantifying movement that is accessible in most environments. However, there is no consensus around the validity and reliability of IMUs for quantifying lumbar spine movements compared with gold standard measures. The aim of this systematic review was to establish concurrent validity and repeated measures reliability of using IMUs for the measurement of lumbar spine movements in individuals with and without LBP. A systematic search of electronic databases, incorporating PRISMA guidelines was completed, limited to the English language. 503 studies were identified where 15 studies met the inclusion criteria. Overall, 305 individuals were included, and 109 of these individuals had LBP. Weighted synthesis of the results demonstrated root mean squared differences of <2.4° compared to the gold standard and intraclass correlations >0.84 for lumbar spine movements. IMUs offer clinicians and researchers valid and reliable measurement of motion in the lumbar spine, comparable to laboratory methods, such as optoelectronic motion capture for individuals with and without LBP.


Asunto(s)
Dolor de la Región Lumbar , Vértebras Lumbares , Movimiento , Dolor de la Región Lumbar/fisiopatología , Humanos , Vértebras Lumbares/fisiopatología , Vértebras Lumbares/fisiología , Reproducibilidad de los Resultados , Fenómenos Biomecánicos
20.
Diabetes Care ; 47(3): 393-400, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38151474

RESUMEN

OBJECTIVE: This multicenter prospective cohort study compared pancreas volume as assessed by MRI, metabolic scores derived from oral glucose tolerance testing (OGTT), and a combination of pancreas volume and metabolic scores for predicting progression to stage 3 type 1 diabetes (T1D) in individuals with multiple diabetes-related autoantibodies. RESEARCH DESIGN AND METHODS: Pancreas MRI was performed in 65 multiple autoantibody-positive participants enrolled in the Type 1 Diabetes TrialNet Pathway to Prevention study. Prediction of progression to stage 3 T1D was assessed using pancreas volume index (PVI), OGTT-derived Index60 score and Diabetes Prevention Trial-Type 1 Risk Score (DPTRS), and a combination of PVI and DPTRS. RESULTS: PVI, Index60, and DPTRS were all significantly different at study entry in 11 individuals who subsequently experienced progression to stage 3 T1D compared with 54 participants who did not experience progression (P < 0.005). PVI did not correlate with metabolic testing across individual study participants. PVI declined longitudinally in the 11 individuals diagnosed with stage 3 T1D, whereas Index60 and DPTRS increased. The area under the receiver operating characteristic curve for predicting progression to stage 3 from measurements at study entry was 0.76 for PVI, 0.79 for Index60, 0.79 for DPTRS, and 0.91 for PVI plus DPTRS. CONCLUSIONS: These findings suggest that measures of pancreas volume and metabolism reflect distinct components of risk for developing stage 3 type 1 diabetes and that a combination of these measures may provide superior prediction than either alone.


Asunto(s)
Diabetes Mellitus Tipo 1 , Humanos , Diabetes Mellitus Tipo 1/diagnóstico , Estudios Prospectivos , Páncreas/diagnóstico por imagen , Páncreas/metabolismo , Factores de Riesgo , Autoanticuerpos , Imagen por Resonancia Magnética
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