Are sleep problems a risk factor for the onset of musculoskeletal pain in children and adolescents? A systematic review

Study Objectives: Musculoskeletal pain is a major burden on the society. Adults with sleep problems are at higher risk of musculoskeletal pain onset, but there is no evidence for this relationship in children and adolescents. This study aimed to systematically review prospective studies on the risk of musculoskeletal pain onset in children and adolescents with sleep problems. Methods: Five databases (MEDLINE, PsycINFO, AMED, EMBASE, and HMIC) were systematically searched to identify prospective studies that investigated if children and adolescents (aged 6–19 years) with sleep problems are at higher risk of musculoskeletal pain onset. Included studies were assessed for study quality and a best evidence synthesis was carried out on extracted data. Results: Thirteen prospective studies were identified. Overall, evidence indicates that sleep problems (quality, quantity, and day time tiredness) are not risk factors for musculoskeletal pain onset. Further analysis on specific body regions shows strong evidence that sleep problems are a risk factor for neck pain onset (only in girls) and that sleep problems are not a risk factor for the onset of widespread pain. Conclusions: Overall, sleep problems are not a risk factor for musculoskeletal pain onset in children and adolescents. Increased risk was found for some specific body regions and subgroups, but the evidence base was less strong and generally inconsistent. This review found a lack of quality in research methodology compared to research in adults, and further research with improved methodology is required

Monte Carlo study of gating and selection in potassium channels

The study of selection and gating in potassium channels is a very important issue in modern biology. Indeed such structures are known in all types of cells in all organisms where they play many important functional roles. The mechanism of gating and selection of ionic species is not clearly understood. In this paper we study a model in which gating is obtained via an affinity-switching selectivity filter. We discuss the dependence of selectivity and efficiency on the cytosolic ionic concentration and on the typical pore open state duration. We demonstrate that a simple modification of the way in which the selectivity filter is modeled yields larger channel efficiency

Microbial-derived pirite as evidence of early diagenetic processes on a Late Holocene shoreface deposits (Sulcis Iglesiente, West Sardinia, Italy)

Since Roman time, SW Sardinia was a mine district and its fluorishing industrial activity lasted few decades ago. Mine activity in the district resulted in enhanced amount of sediments transported by rivers to the coast and, one of the major concern is elucidating the mineralogical background before and after industrial activity along the present-day coasts. A 3-m long core was collected in the shoreface zone, at -13–m depth below sea level and ca. 500 m far from the coastal area located on the southern-western of Sardinia (west Mediterranean, Italy). A multidisciplinary approach was followed to study the core and two samples were collected for dating purpose. 14C analysis revealed a Late Holocene age comprises between 4320 ± 30 BP (base) and 1420 ± 30 yeas BP (close to the top). Preliminary sedimentological data show that the core is composed of medium-fine grained sand, with the presence of aligned pebbles and/or shells at the base of the strata. These strata can be interpreted as the results of major storms occurred in a shoreface setting. Pervasive early diagenetic processes and sub-oxic conditions are observed as well. The preliminary geochemical results can be summarized as follows: 1) residual metal sulphides are not detected; 2) Zn and Pb carbonates can be found in samples collected close to the beaches, 3) barite and other minerals are often concentrated in the fine fraction (<63 microns). Moreover, the microscopic analysis reveals the presence of secondary pyrite that is interpreted to be of microbial origin. Thus the microbial activity most likely plays a fundamental tool in the pervasive early digenesis of the studied core. Bacterial activity and its effect on biominerals processes and sedimentological features are actually under investigation

Renal function is impaired in normotensive chronic HCV patients: role of insulin resistance

Renal dysfunction is an independent predictor for cardiovascular morbidity and mortality. We investigated whether chronic hepatitis C virus (HCV) infection and the related insulin resistance/hyperinsulinemia influence renal function in comparison with a group of healthy subjects and with another group with metabolic syndrome. We enrolled 130 newly diagnosed HCV outpatients matched for age and gender with 130 patients with metabolic syndrome and 130 healthy subjects. Renal function was evaluated by calculation of glomerular filtration rate (e-GFR, mL/min/1.73 m2) using the CKD-EPI equation. The following laboratory parameters were measured: fasting plasma glucose and insulin, total, LDL- and HDL-cholesterol, triglyceride, creatinine, and HOMA to evaluate insulin sensitivity. HCV patients with respect to both healthy subjects and metabolic syndrome patients have a decreased e-GFR: 86.6 ± 16.1 vs 120.2 ± 23.1 mL/min/1.73 m2 (P &lt; 0.0001) and 94.9 ± 22.6 mL/min/1.73 m2 (P = 0.003), respectively. Regarding biochemical variables, HCV patients, in comparison with healthy subjects, have a higher triglyceride level, creatinine, fasting insulin and HOMA (3.4 ± 1.4 vs 2.6 ± 1.3; P &lt; 0.0001). At linear regression analysis, the correlation between e-GFR and HOMA is similar in the metabolic syndrome (r = -0.555, P &lt; 0.0001) and HCV (r = -0.527, P &lt; 0.0001) groups. At multiple regression analysis, HOMA is the major determinant of e-GFR in both groups, accounting for, respectively, 30.8 and 27.8 % of its variation in the metabolic syndrome and HCV. In conclusion, we demonstrate that HCV patients have a significant reduction of e-GFR and that insulin resistance is the major predictor of renal dysfunction

Sympathovagal balance and 1-h postload plasma glucose in normoglucose tolerant hypertensive patients.

AIMS: Normoglucose tolerant (NGT) subjects with a 1-h postload plasma glucose (PLPG) value ≥155 mg/dL have an increased risk of type-2 diabetes and subclinical organ damage. Heart rate variability (HRV) reflects cardiac autonomic balance, frequently impaired in course of diabetes. At this time, no data support the association between 1-h PLPG and HRV; thus, we investigated the possible association between 1-h PLPG and HRV. METHODS: We enrolled 92 never-treated hypertensive subjects (56 women, 36 men), aged 55 ± 9.8 years. During OGTT, the patients underwent electrocardiographic recordings to evaluate HRV in the time domain (SDNN). Insulin sensitivity was assessed by Matsuda index. RESULTS: Among participants, 56 were NGT, 20 had impaired glucose tolerance (IGT), and 16 had type-2 diabetes. According to the 1-h PLPG cutoff point of 155 mg/dL, we divided NGT subjects into: NGT &lt; 155 (n = 38) and NGT ≥ 155 (n = 18). Glucose tolerance status was associated with a significant (P &lt; 0.0001) increase in PLPG and insulin and the reduction in Matsuda index. In all groups, the SDNN values significantly (P &lt; 0.0001) decreased during the first hour of OGTT. A complete recovery in NGT groups was observed at the end of the second hour; in IGT and type-2 diabetes, SDNN remained significantly lower with respect to baseline values. At multiple regression analysis, Matsuda index resulted in the only determinant of SDNN modification, explaining the 12.3 % of its variability. CONCLUSIONS: Our data demonstrate that during OGTT, sympathovagal balance is acutely affected by both glucose and insulin modifications. Particularly, NGT ≥ 155 subjects behave in the same way of IGT and type-2 diabetes patients

Enzyme replacement therapy with agalsidase beta improves cardiac involvement in Fabry's disease.

Fabry's disease is an X-linked lysosomal storage disease caused by a deficiency of alpha-galactosidase that results in an accumulation of neutral glycosphingolipids throughout the body, including the cardiovascular system. Fabry cardiomyopathy, characterized by progressive severe concentric left ventricular (LV) hypertrophy, is very frequent and is the most important cause of death in affected patients. Enzyme replacement therapy (ERT) allows a specific treatment for this disease, however, there are very few data on the effectiveness of therapy on cardiac involvement. Nine patients with Fabry cardiac disease were studied on basal condition and after 6 and 12 months of treatment with algasidase beta (Fabrazyme). A complete clinical, electrocardiographic and echocardiographic evaluation was performed in all patients. Interpretable Doppler recordings of transmitral flow and pulmonary flow velocity curves were also acquired. At baseline, the patients with Fabry's disease had increased LV septum and posterior wall thickness, normal LV fractional shortening, LV ejection fraction, normal Doppler parameters of mitral inflow but a duration of pulmonary vein flow velocity wave exceeding that of the mitral wave at atrial systole. ERT did not affect heart rate and arterial pressure. LV internal diameters did not change, there was a slight but not significant decrease in the LV posterior wall thickening and a progressive decrease in the interventricular septum thickening (p < 0.025) and in LV mass (p < 0.001) The difference in duration between pulmonary vein flow velocity wave and mitral wave at atrial systole significantly decreased (p < 0.001). These results suggest that ERT in patients with Fabry cardiomyopathy is able to reduce the LV mass and ameliorate the LV stiffness

Optimal decay rate for degenerate parabolic equations on noncompact manifolds

We consider an initial value problem for a doubly degenerate parabolic equation in a noncompact Riemannian manifold. The geometrical features of the manifold are coded in either a Faber-Krahn inequality or a relative Faber-Krahn inequality. We prove optimal decay and space-time local estimates of solutions. We employ a simplified version of the by now classical local approach by DeGiorgi, Ladyzhenskaya-Uraltseva, DiBenedetto which is of independent interest even in the euclidean case