Testing the effectiveness of the exercise plus program in older women post-hip fracture

Background: Exercise is an important strategy with potential to improve recovery in older adults following a hip fracture.Purpose: The purpose of this study was to test the impact of a self-efficacy based intervention, the Exercise Plus Program, and the different components of the intervention, on self-efficacy, outcome expectations, and exercise behavior among older women post-hip fracture.Methods: Participants were randomized to one of four groups: exercise plus, exercise only, plus only (i.e., motivation), or routine care. Data collection was done at baseline (within 22 days of fracture), 2, 6, and 12 months post-hip fracture.Results: A total of 209 women were recruited with an average age of 81.0 years (SD=6.9). The majority was White (97.1%), was widowed (57.2%), and had a high school education (66.7%). Generalized Estimating Equations were used to perform repeated measures analyses. No differences in trajectories of recovery were observed for self-efficacy or outcome expectations. A statistically significant difference in the overall trajectory of time in exercise was seen (p<.001), with more time spent exercising in all three treatment groups.Conclusions: The study demonstrated that it was possible to engage these women in a home-based exercise program and that the plus only, exercise only, and the exercise plus groups all increased exercise. Support for this project was provided by National Institute on Aging grants R37 AG09901, R01-AG18668, R01 AG17082, and the Claude D. Pepper Older Americans Independence Center P60-AG12583.     

Loss of T-type Calcium Current in Sensory Neurons of Rats with Neuropathic Pain

Background: Pathophysiology in the primary sensory neuron may contribute to chronic neuropathic pain. Ca channels play a central role in neuronal processes, and sensory neurons are rich in low-voltage-activated calcium channels (LVACCs). However, the physiologic function of these channels is unknown. Their possible role in rebound burst firing makes them a candidate for increased excitability after neuropathic injury.

Methods: This study uses pharmacological methods to isolate LVACC in cells from the dorsal root ganglia of neuropathic and sham-operated rats, including the blockade of high-voltage-activated Ca channels with fluoride and selective toxins. LVACCs were examined with conventional whole cell patch clamp electrophysiology techniques.

Results: After chronic constriction injury of the peripheral axon, LVACC was significantly reduced compared to sham rats as shown by a 60% reduction in peak current density and an 80% reduction in total calcium influx. A depolarizing shift in the voltage dependence of activation and an increase in the rate of deactivation and inactivation appear to cause this reduction of LVACC. Either Ni2+ or mibefradil, blockers of LVACC, applied in the bath to normal dorsal root ganglion cells during current clamp significantly and reversibly increased excitability.     

Epinephrine reduces the sedative side effects of epidural sufentanil for labour analgesia

PURPOSE: The use of opioids in labour analgesia has primarily been as an adjuvant to local anesthetics. For early labour, satisfactory analgesia with epidural sufentanil alone is possible. This study evaluates the impact of epinephrine on sedative side effects and analgesia related to the latter technique. METHODS: After Institutional Review Board approval and informed consent this prospective, randomized, double-blind study evaluated 43 nulliparous subjects requesting epidural analgesia. The study site, a tertiary care obstetric unit, accommodates 3500-4500 deliveries annually. Group selection was randomized and blinded by selection of a sealed envelope containing a number which corresponded to a premixed labelled syringe of saline or epinephrine (100 microg/mL). An epidural catheter was placed in a standardized fashion. All subjects received 40 microg of sufentanil and 0.5 mL from the premixed syringe, diluted to 10 mL with NaCl. A blinded observer collected data on maternal sedation, lightheadedness, hemodynamics, oxygenation, and fetal heart rate over a one-hour period following sufentanil injection. RESULTS: The addition of epinephrine significantly (P <0.05) reduced the incidence of sedation and lightheadedness after epidural sufentanil at all data collection points, except two. Analgesic duration was also significantly prolonged by this addition (120 +/- 56 vs 84 +/- 32 min). Maternal satisfaction was high regardless of solution. CONCLUSION: Forty micrograms of epidural sufentanil produces satisfactory analgesia in early labour. The addition of epinephrine improves the side effect profile of this technique while prolonging the duration of analgesia. Epidural sufentanil requires attention to maternal monitoring of oxygenation as maternal desaturation occurred in both groups.     

The relationship between compulsive behaviour and academic achievement across the three genetic subtypes of Prader–Willi syndrome

Background Prader–Willi syndrome (PWS) is a genetic syndrome associated with several physical, cognitive and behavioural characteristics. For many individuals with this syndrome, compulsive behaviour is often noted in both food and non‐food situations. The focus of this paper is on the non‐food‐related compulsions in individuals with PWS and comparing differences across the three genetic subtypes of the syndrome. Methods Compulsive behaviours in 73 people with PWS were assessed using the Yale‐Brown Obsessive Compulsive Scale and the Compulsive Behavior Checklist. Compulsive behaviour and its relation to IQ and academic achievement also were evaluated. Phenotypic differences were characterized for the three most common genetic subtypes of the disorder: 16 individuals with the long Type I (TI) 15q deletion, 26 individuals with the short Type II (TII) 15q deletion and 31 individuals with maternal disomy 15. Results There appeared to be important differences between the two deletion subtypes. Specifically, individuals with the TI deletion had more compulsions regarding personal cleanliness (i.e. excessive bathing/grooming), and their compulsions were more difficult to interrupt and interfered with social activities more than the other subtypes. Individuals with the TII deletion were more likely to have compulsions related to specific academic areas (i.e. rereading, erasing answers and counting objects or numbers). Conclusions These findings may help clinicians and researchers identify possible intervention strategies and supports based on the behavioural phenotype associated with genetic subtype in individuals with PWS.     

骨骼肌的生物力学

骨骼肌能产生力和运动,肌肉的收缩与运动的激发完美协调。本文回顾骨骼肌的生物力学特点,描述力的产生和力通过肌细胞的传递。首先描述正常的肌肉结构特征和不同的肌肉结构形式,随后讨论肌肉的功能及其结构对功能的影响,分析收缩蛋白与中间肌丝在力从细胞内肌小节传递到细胞外基质过程中的相互作用。     

High-frequency oscillatory ventilation in premature infants with respiratory failure: a preliminary report

High-frequency ventilation has been used successfully to manage life-threatening complications in premature infants with lung disease. Here we report a preliminary assessment of the efficacy and safety of high-frequency oscillatory ventilation-(HFO-A, A = active expiratory phase) when used as a primary ventilator in 11 infants of 24-34 weeks gestation who required ventilatory support. HFO-A was initiated after no more than 5.5 hr of conventional mechanical ventilation (CMV). HFO-A at 15 Hz was used for 12-203 hr following a protocol designed for rapid reduction of FI02 requirements. CO2 elimination was easily achieved in all infants. Oxygenation was satisfactory, except in one infant with congenital pneumonia. There were four deaths during HFO-A: two pulmonary (one congenital pneumonia; one pulmonary hemorrhage) and two nonpulmonary. The HFO-A protocol utilized lung volume recruitment maneuvers plus mean airway pressures (MAwP) greater than those generally used early in the course of CMV. Therefore, in a subset of infants less than or equal to 29 weeks' gestation with respiratory distress syndrome (RDS), ventilator pressures and gas exchange were compared in infants treated with either HFO-A or CMV. Maximum MAwP levels were reached earlier in six infants on HFO-A (5.2 +/- 2.5 hr; mean +/- SD) than in a comparable group of 9 CMV-treated infants (36 +/- 1 hr). This earlier use of high MAwP lowered the FI02 to less than 0.4 by 18.9 +/- 11 hr with HFO-A as compared with 64 +/- 6 hr using CMV, without any evidence of an increase in pulmonary complications. There were 17 complications in the nine CMV-treated infants; and four in the six HFO-A treated ones. We conclude that HFO-A, instituted early and used with a protocol designed for early reduction in FI02 requirements, demonstrates sufficient efficacy and safety to warrant further clinical trials in the routine management of infant RDS.     

Comparison of Methodologies for Calculating Quality Measures Based on Administrative Data versus Clinical Data from an Electronic Health Record System: Implications for Performance Measures

New reimbursement policies and pay-for-performance programs to reward providers for producing better outcomes are proliferating. Although electronic health record (EHR) systems could provide essential clinical data upon which to base quality measures, most metrics in use were derived from administrative claims data. We compared commonly used quality measures calculated from administrative data to those derived from clinical data in an EHR based on a random sample of 125 charts of Medicare patients with diabetes. Using standard definitions based on administrative data (which require two visits with an encounter diagnosis of diabetes during the measurement period), only 75% of diabetics determined by manually reviewing the EHR (the gold standard) were identified. In contrast, 97% of diabetics were identified using coded information in the EHR.The discrepancies in identified patients resulted in statistically significant differences in the quality measures for frequency of HbA1c testing, control of blood pressure, frequency of testing for urine protein, and frequency of eye exams for diabetic patients. New development of standardized quality measures should shift from claims-based measures to clinically based measures that can be derived from coded information in an EHR. Using data from EHRs will also leverage their clinical content without adding burden to the care process.