Efficacy of physical exercise on sleep quality in patients with chronic kidney disease: a systematic review and meta-analysis.

BACKGROUND AND OBJECTIVE: To revise and critically summarize the available scientific evidence regarding the effect of exercise on sleep quality in patients with chronic kidney disease (CKD). METHODS: A systematic review of randomized controlled trials (RCTs) and comparative studies was conducted, searching MEDLINE/PubMed, SPORTDiscus, and Scopus using keywords "Exercise", "Physical Activity", "Chronic Kidney Disease," and "Sleep". The methodological quality of included studies was assessed using the PEDRo and MINORS scales. RESULTS: A total of 8 RCTs and 3 comparative studies were included, showing a low (n = 1), fair (n = 7), and good (n = 3) methodological quality. Most of the studies included patients undergoing hemodialysis (HD) (n = 8). Self-reported sleep quality (n = 9), sleepiness (n = 2), and objective sleep status (n = 2) were the main outcomes analyzed. The most frequent exercise interventions included aerobic training (n = 7), resistance training (n = 2), or a combination of both (n = 4). Generally, exercise induced positive effects on the reported outcomes. Data synthesis indicated that participants who exercised obtained significant improvements on their self-reported sleep quality in comparison with those included in the control groups, with a mean difference in the Pittsburgh Sleep Quality Index of - 5.27 points (95% CI - 7.76, - 2.77; p < 0.001). CONCLUSION: Preliminary scientific evidence indicates that patients with CKD, especially those undergoing HD, report improvements in self-reported sleep quality after taking part in aerobic exercise programs, while combined training interventions yielded diverse findings. The effects of exercise on sleepiness and objective sleep status were backed by few studies with mixed results.

Eclampsia y síndrome HELLP en los Andes del Perú: complicaciones perinatales / Eclampsia and HELLP syndrome in the Peruvian Andes: perinatal complications

Resumen OBJETIVO: Comparar las complicaciones perinatales en pacientes con eclampsia, síndrome HELLP y su asociación. MATERIALES Y MÉTODOS: Estudio transversal y comparativo efectuado en mujeres con eclampsia, síndrome HELLP, o ambos, y sus neonatos atendidas en el Hospital Regional Docente de Cajamarca, Perú, entre el 1 de enero y el 31 de diciembre de 2015. La información se procesó con el programa Epi Info versión 7. Se usó la ANOVA y χ2 no paramétrica con Kruskal-Wallis para comparar grupos, y se consideró significativo un valor de p < 0.05. RESULTADOS: Se registraron 3411 nacimientos; 71 pacientes tuvieron eclampsia o síndrome HELLP. Las complicaciones perinatales de prematurez, menor peso y talla al nacer y Apgar más bajo fueron significativamente mayores en mujeres con síndrome HELLP que con eclampsia. En cuanto a prematurez hubo 30 (66.6%) casos de madres con síndrome HELLP, 14 (70%) con eclampsia asociada con síndrome HELLP y ninguno con eclampsia (p = 0.01). El peso promedio al nacimiento fue 2133.5 ± 66.7 g en síndrome HELLP y 3083.1 ± 67.8 g en eclampsia (p = 0.001). Hubo Apgar más bajo al minuto y a los cinco minutos en la combinación eclampsia y síndrome HELLP que en solo eclampsia (p = 0.002). No hubo diferencias significativas en la mortalidad, restricción del crecimiento fetal, asfixia neonatal, taquipnea transitoria, enfermedad de membranas hialinas, enterocolitis necrotizante, policitemia, ictericia patológica o sepsis. La tasa de cesáreas en síndrome HELLP fue 41 (91.1%) y en eclampsia 4 (66.6%) (p = 0.03). CONCLUSIONES: Las complicaciones perinatales son mayores pacientes con síndrome HELLP que con eclampsia.

Abstract OBJECTIVES: To compare perinatal complications in patients with eclampsia, HELLP syndrome and association. MATERIALS AND METHODS: a cross-sectional, comparative study conducted in women with eclampsia and / or HELLP syndrome and their perinates in Hospital Regional Docente de Cajamarca , Peru. Data obtained from 01/01/2015 to 12/31/15. Information processing was carried out with the Epi Info program version 7. The ANOVA and non-parametric χ2 with Kruskal-Wallis were used to compare groups, and a value of P <0.05 was considered significant. RESULTS: 71 women had eclampsia and / or HELLP syndrome of 3411 births. Perinatal complications such as prematurity, lower weight and height at birth and lower Apgar were significantly higher in HELLP syndrome than in eclampsia. Regarding prematurity, there were 30 (66.6%) in HELLP syndrome, 14 (70%) in eclampsia associated with HELLP syndrome and none in eclampsia (p = 0.01). Birth weight was 2133.5 ± 66.7 g in HELLP syndrome and 3083.1 ± 67.8 g in eclampsia (p = 0.001). Apgar was lower at minute and at 5 minutes in the combination eclampsia and HELLP syndrome than in eclampsia alone (p = 0.002). There were no significant differences in mortality, IUGR, neonatal asphyxia, transient tachypnea, hyaline membrane disease, necrotizing enterocolitis, polycythemia, pathological jaundice or sepsis. The rate of cesareans in HELLP syndrome was 41 (91.1%) and in eclampsia 4 (66.6%) (p = 0.03). CONCLUSIONS: Perinatal complications are greater in HELLP syndrome than in eclampsia.

Sparse Labeling PELDOR Spectroscopy on Multimeric Mechanosensitive Membrane Channels.

Pulse electron paramagnetic resonance (EPR) is being applied to ever more complex biological systems comprising multiple subunits. Membrane channel proteins are of great interest as pulse EPR reports on functionally significant but distinct conformational states in a native environment without the need for crystallization. Pulse EPR, in the form of pulsed electron-electron double resonance (PELDOR), using site-directed spin labeling, is most commonly employed to accurately determine distances (in the nanometer range) between different regions of the structure. However, PELDOR data analysis is more challenging in systems containing more than two spins (e.g., homomultimers) due to distorting multispin effects. Without suppression of these effects, much of the information contained in PELDOR data cannot be reliably retrieved. Thus, it is of utmost importance for future PELDOR applications in structural biology to develop suitable approaches that can overcome the multispin problem. Here, two different approaches for suppressing multispin effects in PELDOR, sparse labeling of the protein (reducing the labeling efficiency f) and reducing the excitation probability of spins (λ), are compared on two distinct bacterial mechanosensitive channels. For both the pentameric channel of large conductance (MscL) and the heptameric channel of small conductance (MscS) of Escherichia coli, mutants containing a spin label in the cytosolic or the transmembrane region were tested. Data demonstrate that distance distributions can be significantly improved with either approach compared to the standard PELDOR measurement, and confirm that λ < 1/(n-1) is needed to sufficiently suppress multispin effects (with n being the number of spins in the system). A clear advantage of the sparse labeling approach is demonstrated for the cytosolic mutants due to a significantly smaller loss in sensitivity. For the transmembrane mutants, this advantage is less pronounced but still useful for MscS, but performance is inferior for MscL possibly due to structural perturbations by the bulkier diamagnetic spin label analog.

Accurate Extraction of Nanometer Distances in Multimers by Pulse EPR.

Pulse electron paramagnetic resonance (EPR) is gaining increasing importance in structural biology. The PELDOR (pulsed electron-electron double resonance) method allows extracting distance information on the nanometer scale. Here, we demonstrate the efficient extraction of distances from multimeric systems such as membrane-embedded ion channels where data analysis is commonly hindered by multi-spin effects.

Strategies for the synthesis of yardsticks and abaci for nanometre distance measurements by pulsed EPR.

Pulsed electron paramagnetic resonance (EPR) techniques have been found to be efficient tools for the elucidation of structure in complex biological systems as they give access to distances in the nanometre range. These measurements can provide additional structural information such as relative orientations, structural flexibility or aggregation states. A wide variety of model systems for calibration and optimisation of pulsed experiments has been synthesised. Their design is based on mimicking biological systems or materials in specific properties such as the distances themselves and the distance distributions. Here, we review selected approaches to the synthesis of chemical systems bearing two or more spin centres, such as nitroxide or trityl radicals, metal ions or combinations thereof and outline their application in pulsed EPR distance measurements.

A modular approach for the synthesis of nanometer-sized polynitroxide multi-spin systems.

The synthesis of rigid symmetric polyradical model systems with inter-spin distances between 1.4 and 4 nm and their room temperature continuous wave (CW) EPR spectra are reported. Conditions for attachment of the spin-label via esterification have been optimized on the direct synthesis of polyradicals from commercially available polyphenols and the carboxylic acid functionalized nitroxide TPC. A common synthetic protocol utilizing 4-hydroxy-4'-iodobiphenyl as a key building block has been used to synthesize an equilateral biradical and a triradical in only two steps from commercially available starting materials. The first synthesis of a tetraradical based upon an adamantane core bearing six equivalent nitroxide-nitroxide distances is also reported. These systems are very promising candidates for studying multi-spin effects in pulsed EPR distance measurements.