Discovering how organisms and their proteins adapt to extreme conditions is a complicated process. Every condition has its own set of adaptations that make it uniquely stable in its environment. The ...purpose of our review is to discuss what is known in the extremophilic community about protein adaptations. To simplify our mission, we broke the extremophiles into three broad categories: thermophiles, halophiles and psychrophiles. While there are crossover organisms- organisms that exist in two or more extremes, like heat plus acid or cold plus pressure, most of them have a primary adaptation that is within one of these categories which tends to be the most easily identifiable one. While the generally known adaptations are still accepted, like thermophilic proteins have increased ionic interactions and a hardier hydrophobic core, halophilic proteins have a large increase in acidic amino acids and amino acid/peptide insertions and psychrophiles have a much more open structure and reduced ionic interactions, some new information has come to light. Thermophilic stability can be improved by increased subunit-subunit or subunit-cofactor interactions. Halophilic proteins have reversible folding when in the presence of salt. Psychrophilic proteins have an increase in cavities that not only decrease the formation of ice, but also increase flexibility under low temperature conditions. In a proof of concept experiment, we applied what is currently known about adaptations to a well characterized protein, malate dehydrogenase (MDH). While this protein has been profiled in the literature, we are applying our adaptation predictions to its sequence and structure to see if the described adaptations apply. Our analysis demonstrates that thermophilic and halophilic adaptations fit the corresponding MDHs very well. However, because the number of psychrophiles MDH sequences and structures is low, our analysis on psychrophiles is inconclusive and needs more information. By discussing known extremophilic adaptations and applying them to a random, conserved protein, we have found that general adaptations are conserved and can be predicted in proposed extremophilic proteins. The present field of extremophile adaptations is discovering more and more ways organisms and their proteins have adapted. The more that is learned about protein adaptation, the closer we get to custom proteins, designed to fit any extreme and solve some of the world’s most pressing environmental problems.
Abstract Brininger TL, Rogers JC, Holm MB, Baker NA, Li Z-M, Goitz RJ. Efficacy of a fabricated customized splint and tendon and nerve gliding exercises for the treatment of carpal tunnel syndrome: a ...randomized controlled trial. Objective To compare the effects of a neutral wrist and metacarpophalangeal (MCP) splint with a wrist cock-up splint, with and without exercises, for the treatment of carpal tunnel syndrome (CTS). Design A 2×2×3 randomized factorial design with 3 main factors: splint (neutral wrist and MCP and wrist cock-up), exercise (exercises, no exercise), and time (baseline, 4wk, 8wk). Setting Subjects were evaluated in an outpatient hand therapy clinic. Participants Sixty-one subjects with mild to moderate CTS; 51 subjects completed the study. Interventions There were 4 groups: the neutral wrist and MCP group and the neutral wrist and MCP-exercise group received fabricated customized splints that supported the wrist and MCP joints; the wrist cock-up group and the wrist cock-up-exercise group received wrist cock-up splints. The neutral wrist and MCP-exercise and wrist cock-up-exercise groups also received tendon and nerve gliding exercises and were instructed to perform exercises 3 times a day. All subjects were instructed to wear the assigned splint every night for 4 weeks. Main Outcome Measures We used the CTS Symptom Severity Scale (SSS) and the Functional Status Scale (FSS) to assess CTS symptoms and functional status. Results Analysis of variance showed a significant main effect for splint and time on the SSS ( P <.001, P =.014) and FSS ( P <.001, P =.029), respectively. There were no interaction effects. Conclusions Our results validate the use of wrist splints for the treatment of CTS, and suggest that a splint that supports the wrist and MCP joints in neutral may be more effective than a wrist cock-up splint.
The purpose of this prospective cohort study was to investigate physical, occupational, and psychosocial risk factors for musculoskeletal injuries (MSI) in deployed female soldiers. Before ...deployment, participants completed performance testing and surveys and after deployment an additional survey detailing occupational demands and MSI. Data analyzed found 57/160 (36%) suffered 78 MSI. In unadjusted analyses, these factors increased the relative risk (RR, 95% confidence interval) of injury: wearing an average load >10% body weight (BW) (RR = 2.00, 1.31-4.57), wearing an average load >1 hour (RR = 2.44, 1.30-4.57), heaviest load worn >15% BW (RR = 5.83, 1.51-22.50), wearing a backpack (RR = 1.82, 1.23-2.80), wearing body armor >1 hour (RR = 1.62, 1.002-2.62), lifting objects weighing above 22.68 kg (RR = 1.96, 1.08-3.57), lifting objects one to two times (RR = 1.73, 1.002-2.97), carrying objects >7.62 m (RR = 2.01, 1.19-3.42), and Y Balance composite score <95.23 (RR = 1.71, 1.13-2.60). The best logistic regression model predicting MSI was average load as % BW (odds ratio OR = 1.04, 1.01-1.07), heaviest load as % BW (OR = 1.03, 1.01-1.05), average repetitions lifting objects (OR = 1.07, 1.01-1.14), and sit-ups (OR = 0.93, 0.93-0.99). Results indicate that risk of MSI in deployed female soldiers increased with heavier equipment worn and more repetitious lifting, although more performing more sit-ups on the fitness test before deployment reduced the risk.
Many studies have quantified use of established refuges where hunting is not permitted by counting waterfowl or conducting behavioral observations on refuges during hunting season. However, refuge ...use by individually marked birds remains largely unexplored, along with arrival and departure times, lengths of stay, and nighttime use. We used radio-transmitters and telemetry receiving stations that continuously scanned at 14 waterfowl refuges to test predictions that refuge use would be greatest during hunting hours and on weekends when hunting intensity was expected to be greatest, and that departures would occur in the evening after hunting ended. Movements on and off refuges coincided with sunrise and sunset, which approximated hunting hours. The average length of refuge stay was 12.0 ± 0.5 hours, although some departing birds returned repeatedly to refuges, resulting in longer accumulative stays. Use during the day was greater than at night at most refuges (92.7 ± 18.1 vs. 56.1 ± 10.8 hr, P= 0.03) and was greater on weekends during hunting season than before hunting opened (0.36 ± 0.03 vs. 0.22 ± 0.05, P= 0.01). We also documented nighttime use at refuges with good or excellent food ratings by wildlife managers. Our findings are consistent with the use of refuges to avoid disturbance and suggest that many of these areas provide numerous benefits to ring-necked ducks during fall staging and migration in northern Minnesota. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
Each year musculoskeletal injuries (MSIs) result in thousands of lost duty days and medical discharges. Women represent 15% of the Army and have higher incidence of injury than male soldiers; studies ...that have investigated MSIs in deployed women are lacking. Therefore, the purpose of this prospective cohort study was to investigate MSIs in women during a 9-month deployment to Afghanistan. Participants were recruited from three Brigade Combat Teams. Participants completed a demographic survey before deployment and a second survey on occupational demands and MSIs after deployment. Of the 160 women, 57 (36%) suffered 78 MSIs resulting in 1,642 days of limited duty, a median of 7 days per MSI, losing 10% of the available duty time to MSIs. Most injuries affected the knee (24%) or low back (18%). Soldiers attributed the majority of injuries (27%) to physical training and trips/falls (17%). Of the MSIs, 93% caused limitations to physical training and 76% resulted in large limitations to occupational tasks. Most MSIs (41%) resolved within 3 weeks and most (37%) occurred before the fourth month of deployment. Prevention measures should target knee and low back injuries. Physical training should be further investigated to discover modifications capable of reducing injuries.
The purpose of the current study was to examine motion enslaving characteristics of multiple fingers during isolated flexion of the distal interphalangeal joints. Because the distal interphalangeal ...joints are flexed by multiple tendons of the single flexor digitorum profundus, the current experimental design provided a unique advantage to understand inter-finger enslaving effects due to the flexor digitorum profundus. Eight subjects were instructed to flex the distal interphalangeal joint of each individual finger from the fully extended position to the fully flexed position as quickly as possible. Maximal angular displacements, velocities, or accelerations of individual fingers were used to calculate the enslaving effects. An independence index, defined as the ratio of the maximal displacement of a master finger to the sum of the maximal displacements of the master and slave fingers, was used to quantify relative independence of each finger. The angular displacements of the index, middle, ring, and little fingers were 68.6(degrees) (+/-7.7), 68.1(degrees) (+/-10.1), 68.1(degrees) (+/-9.7), and 74.7(degrees) (+/-13.3), respectively. The motion of a master finger was invariably accompanied by motion of 1 or 2 slave fingers. Angular displacements of master and slave fingers increased to maximum values with time monotonically. Velocity curves demonstrated bell-shaped profile, and the acceleration curves were sinusoidal. Enslaving effects were generated mainly on the neighboring fingers. The amount of enslaving on the middle and ring fingers exceeded more than 60% of their own maximum angular displacements when a single adjacent finger moved. The index finger had the highest level of independence as indicated by the lowest enslaving effects on other fingers or by other fingers. The independence indices of the index, middle, ring, and little fingers were 0.812 (+/-0.070), 0.530 (+/-0.051), 0.479 (+/-0.099), and 0.606 (+/-0.148), respectively. In all tasks, motion of slave fingers always lagged with respect to the master finger. Time delays, on average, ranged from 7.8 (+/-5.0) to 35.9 (+/-22.1) ms. Our results suggest that there exist relatively large enslaving effects among the compartments of the flexor digitorum profundus, and functional independence of fingers in daily activities is likely enhanced through synergistic activities of multiple muscles, including flexors and extensor.
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