139 research outputs found
Electron Transfer Pathways and Dynamics of Chloroplast NADPH-dependent Thioredoxin Reductase C (NTRC)
NADPH-dependent thioredoxin reductases (NTRs) contain a flavin cofactor and a disulfide as redox-active groups. The catalytic mechanism of standard NTR involves a large conformational change between two configurations. Oxygenic photosynthetic organisms possess a plastid-localized NTR, called NTRC, with a thioredoxin module fused at the C terminus. NTRC is an efficient reductant of 2-Cys peroxiredoxins (2-Cys Prxs) and thus is involved in the protection against oxidative stress, among other functions. Although the mechanism of electron transfer of canonical NTRs is well established, it is not yet known in NTRC. By employing stopped-flow spectroscopy, we have carried out a comparative kinetic study of the electron transfer reactions involving NTRC, the truncated NTR module of NTRC, and NTRB, a canonical plant NTR. Whereas the three NTRs maintain the conformational change associated with the reductive cycle of catalysis, NTRC intramolecular electron transfer to the thioredoxin module presents two kinetic components (kET of ∼2 and 0.1 s−1), indicating the occurrence of additional dynamic motions. Moreover, the dynamic features associated with the electron transfer to the thioredoxin module are altered in the presence of 2-Cys Prx. NTRC shows structural constraints that may locate the thioredoxin module in positions with different efficiencies for electron transfer, the presence of 2-Cys Prx shifting the conformational equilibrium of the thioredoxin module to a specific position, which is not the most efficien
Smart vest for respiratory rate monitoring of COPD patients based on non-contact capacitive sensing
In this paper, a first approach to the design of a portable device for non-contact monitoring
of respiratory rate by capacitive sensing is presented. The sensing system is integrated into a smart
vest for an untethered, low-cost and comfortable breathing monitoring of Chronic Obstructive
Pulmonary Disease (COPD) patients during the rest period between respiratory rehabilitation
exercises at home. To provide an extensible solution to the remote monitoring using this sensor and
other devices, the design and preliminary development of an e-Health platform based on the Internet
of Medical Things (IoMT) paradigm is also presented. In order to validate the proposed solution,
two quasi-experimental studies have been developed, comparing the estimations with respect to the
golden standard. In a first study with healthy subjects, the mean value of the respiratory rate error,
the standard deviation of the error and the correlation coefficient were 0.01 breaths per minute (bpm),
0.97 bpm and 0.995 (p < 0.00001), respectively. In a second study with COPD patients, the values
were -0.14 bpm, 0.28 bpm and 0.9988 (p < 0.0000001), respectively. The results for the rest period
show the technical and functional feasibility of the prototype and serve as a preliminary validation of
the device for respiratory rate monitoring of patients with COPD.Ministerio de Ciencia e Innovación PI15/00306Ministerio de Ciencia e Innovación DTS15/00195Junta de Andalucía PI-0010-2013Junta de Andalucía PI-0041-2014Junta de Andalucía PIN-0394-201
“External and total hip rotation range of motion predispose to low back pain in elite Spanish inline hockey player”
Low back pain (LBP) is a common ailment in competitive athletes. Although the association
between limited range of motion (ROM) and prevalence of LBP has been widely investigated in other
sports, there is no research about this topic in inline hockey (IH). The main purposes of this study in IH
players were (1) to analyze the association between hip ROM and LBP and (2) to establish a diagnostic
cuto for ROM of high risk of LBP. Twenty elite IH players from the two Spanish National Teams
(male and female) were assessed for passive maximum hip ROMs; the movement evaluated were the
hip external [HER] and internal [HIR] rotation, hip flexion with flexed [HF-KF] and extended [HF-KE]
knee, hip adduction with flexed hip [HAD-HF], hip abduction with neutral [HAB] and flexed [HAB-HF]
hip, and hip extension [HE]. LBP was retrospectively monitored for the last 12 months before the date of
ROM assessment by using a questionnaire. The data were analyzed via a binary logistic regression and
receiver operating characteristic curves. The 70% of players had developed LBP during the retrospective
study period. Significant dierences between LBP group and asymptomatic group for HER (p = 0.013,
d [Cohen’s eect size] = 1.17) and hip total rotation [HTR] (p = 0.032, d [Cohen’s eect size] = 1.05) were
observed. The cuto points with the greatest discriminatory capacity were 56.5 for HER and 93 for
HTR ROMs
The novel adaptor protein Tks4 (SH3PXD2B) is required for functional podosome formation.
Metastatic cancer cells have the ability to both degrade and migrate through the extracellular matrix (ECM). Invasiveness can be correlated with the presence of dynamic actin-rich membrane structures called podosomes or invadopodia. We showed previously that the adaptor protein tyrosine kinase substrate with five Src homology 3 domains (Tks5)/Fish is required for podosome/invadopodia formation, degradation of ECM, and cancer cell invasion in vivo and in vitro. Here, we describe Tks4, a novel protein that is closely related to Tks5. This protein contains an amino-terminal Phox homology domain, four SH3 domains, and several proline-rich motifs. In Src-transformed fibroblasts, Tks4 is tyrosine phosphorylated and predominantly localized to rosettes of podosomes. We used both short hairpin RNA knockdown and mouse embryo fibroblasts lacking Tks4 to investigate its role in podosome formation. We found that lack of Tks4 resulted in incomplete podosome formation and inhibited ECM degradation. Both phenotypes were rescued by reintroduction of Tks4, whereas only podosome formation, but not ECM degradation, was rescued by overexpression of Tks5. The tyrosine phosphorylation sites of Tks4 were required for efficient rescue. Furthermore, in the absence of Tks4, membrane type-1 matrix metalloproteinase (MT1-MMP) was not recruited to the incomplete podosomes. These findings suggest that Tks4 and Tks5 have overlapping, but not identical, functions, and implicate Tks4 in MT1-MMP recruitment and ECM degradation.Peer reviewe
The role of daily physical activity and nutritional status on bone turnover in cystic fibrosis: a cross-sectional study
The novel adaptor protein Tks4 (SH3PXD2B) is required for functional podosome formation.
Metastatic cancer cells have the ability to both degrade and migrate through the extracellular matrix (ECM). Invasiveness can be correlated with the presence of dynamic actin-rich membrane structures called podosomes or invadopodia. We showed previously that the adaptor protein tyrosine kinase substrate with five Src homology 3 domains (Tks5)/Fish is required for podosome/invadopodia formation, degradation of ECM, and cancer cell invasion in vivo and in vitro. Here, we describe Tks4, a novel protein that is closely related to Tks5. This protein contains an amino-terminal Phox homology domain, four SH3 domains, and several proline-rich motifs. In Src-transformed fibroblasts, Tks4 is tyrosine phosphorylated and predominantly localized to rosettes of podosomes. We used both short hairpin RNA knockdown and mouse embryo fibroblasts lacking Tks4 to investigate its role in podosome formation. We found that lack of Tks4 resulted in incomplete podosome formation and inhibited ECM degradation. Both phenotypes were rescued by reintroduction of Tks4, whereas only podosome formation, but not ECM degradation, was rescued by overexpression of Tks5. The tyrosine phosphorylation sites of Tks4 were required for efficient rescue. Furthermore, in the absence of Tks4, membrane type-1 matrix metalloproteinase (MT1-MMP) was not recruited to the incomplete podosomes. These findings suggest that Tks4 and Tks5 have overlapping, but not identical, functions, and implicate Tks4 in MT1-MMP recruitment and ECM degradation.Peer reviewe
The role of daily physical activity and nutritional status on bone turnover in cystic fibrosis: a cross-sectional study
Background: Nutritional status and daily physical activity (PA) may be an excellent tool for the maintenance
of bone health in patients with cystic fibrosis (CF). Objective: To evaluate the relationship between nutritional status,
daily physical activity and bone turnover in cystic fibrosis patients. Method: A cross-sectional study of adolescent and
adult patients diagnosed with clinically stable cystic fibrosis was conducted. Total body, femoral neck, and lumbar spine
bone mineral density (BMD) were determined by dual energy X-ray absorptiometry and bone metabolism markers ALP,
P1NP, PICP, and ß-CrossLaps. PA monitoring was assessed for 5 consecutive days using a portable device. Exercise
capacity was also determined. Serum 25-hydroxyvitamin D and vitamin K were also determined in all participants.
Results: Fifty patients (median age: 24.4 years; range: 16-46) were included. BMI had positive correlation with all BMD
parameters, with Spearman’s coefficients ranging from 0.31 to 0.47. Total hip bone mineral density and femoral neck
BMD had positive correlation with the daily time spent on moderate PA (>4.8 metabolic equivalent-minutes/day; r=0.74,
p7.2 metabolic equivalent-minutes/day; r=0.45
p<0.001), body mass index (r=0.44, p=0.001), and muscle mass in limbs (r=0.41, p=0.004). Levels of carboxy-terminal
propeptide of type 1 collagen were positively associated with the daily time spent on moderate (r=0.33 p=0.023) and
vigorous PA (r=0.53, p<0.001). Conclusions: BMI and the daily time spent on moderate PA were found to be correlated
with femoral neck BMD in CF patients. The association between daily PA and biochemical markers of bone formation
suggests that the level of daily PA may be linked to bone health in this patient group. Further research is needed to
confirm these findings
Fiabilidad absoluta de 2 pruebas de valoración del rango de movimiento del tobillo en jugadores de balonmano
El objetivo de este estudio fue examinar la fiabilidad absoluta de las pruebas de estimación de la flexibilidad de la musculatura del tríceps sural ROMsoleo y ROM-gemelo a través de un diseño de medidas repetidas. 25 jugadores senior de balonmano completaron 3 sesiones de evaluación del ROM articular de la dorsi-flexión del tobillo con rodilla flexionada (ROM-soleo) y extendida (ROM-gemelo) con un intervalo de 2 semanas entre sesiones consecutivas. La fiabilidad absoluta fue examinada mediante el cálculo de los estadísticos cambio en la media (CM) entre sesiones de valoración, porcentaje del error típico (CVET) e índice de correlación intraclase (ICC). Los resultados del actual estudio demuestran que las pruebas ROM-soleo y ROM-gemelo presentan una elevada fiabilidad absoluta (CM<1%; CVET<4,6%; ICC>0,92)
Perfil de flexibilidad de la extremidad inferior en jugadores senior de balonmano
El objetivo de este estudio fue definir los valores de referenciadel perfil de flexibilidad de la extremidad inferior en jugadores senior debalonmano. Para ello, se valoró la flexibilidad de los principales gruposmusculares de la extremidad inferior (psoas ilíaco, cuádriceps, aductores,isquiosurales, glúteo mayor, gemelo y soleo). 56 jugadores senior de balonmanocon más de 9 años de experiencia tomaron parte en este estudio.Los resultados del presente estudio definen como perfil de flexibilidad dela muestra los siguientes valores de referencia: 41,2º para el gemelo, 43,1ºpara el sóleo, 147,8º para el glúteo mayor, 82,9º para la musculatura isquiosural,47,5º para los aductores, 18,5º para el psoas iliaco y 125,2º parael cuádriceps. A su vez, los resultados del presente estudio demuestran quelos jugadores de balonmano analizados presentan un perfil de flexibilidadde la extremidad inferior superior a los valores propuestos para poblacióngeneral, a los valores encontrados en sujetos sanos sedentarios, o en personasfísicamente activas. De la misma forma, los valores de flexibilidadde los jugadores de balonmano del presente estudio son superiores o similaresa los observados en otros deportes (tenis, fútbol, corredores de largadistancia), excepto para la flexibilidad de la musculatura isquiosural y delpsoas iliaco. Finalmente, no se han encontrado desequilibrios muscularescontra laterales entre ambos lados corporales en ninguno de los músculosevaluados
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