56 research outputs found
EFFECT OF THE MECHANICAL CONSTRAINTS ON MULTI-FINGER PREHENSION
INTRODUCTION: When a finger produces a force, other non-task fingers of the hand also produce an involuntary force. This phenomenon has been known as finger enslaving (Zatsiorsky et al. 1998). In the present study, we examined the characteristics of the enslaving matrices obtained by the fixed object prehension and the free object prehension. Previous studies showed that two innate constraints (i.e. peripheral and central constraints) affect the performance of finger force production during fixed object prehension. However, it is unknown how the mechanical constraints, which are imposed externally, play a role in grasping tasks. The purpose of the current study was to investigate the finger enslaving for the fixed and free object prehension during maximum finger force production tasks in statics.
The central nervous system (CNS) is required to satisfy linear and rotational equilibrium during the free object prehension, while the CNS does not need to satisfy any external constraint
TRAINING-SPECIFIC ADAPTATION OF MULTI-FINGER COORDINATION
The purpose of the present study was to investigate the effects of finger Strength Training (ST) on multi-finger coordination as well as individual finger control, independence, and strength. Thirty-three healthy, young subjects were randomly assigned into four groups. Group 1 (G1) trained all fingers together, Group 2 (G2) trained individual fingers without restricting movements of the non-training fingers, and Group 3 (G3) trained individual fingers while restricting the movement of the non-training fingers.
The control group (G0) did not undergo any training. All subjects in G1, G2, and G3 performed six sets of ten repetitions at 70% of their one repetition maximum for each sesson for six weeks, and there were three sessions of training per week. Identical experimental tests were conducted four times, biweekly, across the six-week training.
Moment stabilizing multi-finger coordination increased only in G1, while force stabilizing coordination increased only in G3. Finger strength increased significantly in all training groups. Finger force control errors decreased significantly with ST for all the training groups. Finger independence also decreased significantly for all the training groups. We conclude that the neuromuscular adaptations to finger ST are specific to the training protocol being employed, yielding improvements in different types of multi-finger coordination (i.e., ST specificity for coordination), finger force control, finger strength and a decrease in finger independence. We suggest that ST protocol should be carefully designed for the improvement of specific coordination of multi-effector motor systems
Sensory-to-Motor Overflow: Cooling Foot Soles Impedes Squat Jump Performance
Partial funding for Open Access provided by the UMD Libraries' Open Access Publishing Fund.Evidence from recent studies on animals and humans suggest that neural overflow from the primary sensory cortex (S1) to the primary motor cortex (M1) may play a critical role in motor control. However, it is unclear if whole-body maximal motor tasks are also governed by this mechanism. Maximum vertical squat jumps were performed by 15 young adults before cooling, then immediately following a 15-min cooling period using an ice-water bath for the foot soles, and finally immediately following a 15-min period of natural recovery from cooling. Jump heights were, on average, 3.1 cm lower immediately following cooling compared to before cooling (p = 3.39 ร 10โ8) and 1.9 cm lower following natural recovery from cooling (p = 0.00124). The average vertical ground reaction force (vGRF) was also lower by 78.2 N in the condition immediately following cooling compared to before cooling (p = 8.1 ร 10โ5) and 56.7N lower following natural recovery from cooling (p = 0.0043). The current study supports the S1-to-M1 overflow mechanism in a whole-body dynamic jump
A Prospective Multi-center Trial of Escherichia coli Extract for the Prophylactic Treatment of Patients with Chronically Recurrent Cystitis
We have assessed the efficacy and safety of Escherichia coli extract (ECE; UroVaxom (R)) which contains active immunostimulating fractions, in the prophylactic treatment of chronically recurrent cystitis. Forty-two patients with more than 2 episodes of cystitis in the proceeding 6 months were treated for 3 months with one capsule daily of ECE and observed for a further 6 months. The primary efficacy criterion was the number of episodes of recurrent cystitis during the 6 months after treatment compared to those during the 6 months before treatment. At the end of the 9-month trial, 34 patients (all women) were eligible for statistical analysis. Their mean age was 56.4 yr (range, 34-75 yr), and they had experienced recurrent urinary tract infections for 7.2 +/- 5.2 yr. The number of recurrences was significantly lower during the 6-month follow-up period than during the 6 months preceding the trial (0.35 vs. 4.26, P<0.001). During the follow-up, 28 (82.4%) patients had no recurrences and 4 (11.8%) had 1 each. In patients who relapsed, ECE alleviated cystitis symptoms, including painful voiding, frequency and urgency. There were no serious adverse events related to the study drug. Our study demonstrates the efficacy and safety of ECE in the prophylactic treatment of chronically recurrent cystitis.Ha US, 2008, INT J ANTIMICROB AG, V31, pS63, DOI 10.1016/j.ijantimicag.2007.07.018LEE SJ, 2008, KOREAN J UROL, V48, P428Krieger JN, 2002, J UROLOGY, V168, P2351, DOI 10.1097/01.ju.0000037620.30988.b2Barnett BJ, 1997, AM J MED SCI, V314, P245Nicolle LE, 1997, INFECT DIS CLIN N AM, V11, P647Baier W, 1997, ARZNEIMITTEL-FORSCH, V47, P980Lettgen B, 1996, CURR THER RES CLIN E, V57, P464AVORN J, 1994, JAMA-J AM MED ASSOC, V271, P751MAGASI P, 1994, EUR UROL, V26, P137SCHULMAN CC, 1993, J UROLOGY, V150, P917JACOBY GA, 1991, NEW ENGL J MED, V324, P601NAUCK M, 1991, INT J EXP CLIN CHEMO, V4, P1SOTOLONGO JR, 1990, J UROLOGY, V143, P979VANPHAM T, 1990, J BIOL RESP MODIF, V9, P231TAMMEN H, 1990, BRIT J UROL, V65, P6HANSSON S, 1989, BRIT MED J, V298, P856HANSSON S, 1989, BRIT MED J, V298, P853WYBRAN J, 1989, IMMUNOPHARM IMMUNOT, V11, P17BOSCH A, 1988, IMMUNOPHARM IMMUNOT, V10, P333TAMMEN H, 1988, UROLOGE, V28, P294BOTTEX C, 1988, INT J IMMUNOTHER, V4, P203FREY C, 1986, UROL INT, V41, P444HAUSER WE, 1982, AM J MED, V72, P711
Development of an Animal Experimental Model for a Bileaflet Mechanical Heart Valve Prosthesis
The objective of this study was to develop a pre-clinical large animal model for the in vivo hemodynamic testing of prosthetic valves in the aortic position without the need for cardiopulmonary bypass. Ten male pigs were used. A composite valved conduit was constructed in the operating room by implanting a prosthetic valve between two separate pieces of vascular conduits, which bypassed the ascending aorta to the descending aorta. Prior to applying a side-biting clamp to the ascending aorta for proximal grafting to the aortic anastomosis, an aorta to femoral artery shunt was placed just proximally to this clamp. The heart rate, cardiac output, Vmax, transvalvular pressure gradient, effective orifice area and incremental dobutamine stress response were assessed. A dose dependant increase with dobutamine was seen in terms of cardiac output, Vmax, and the peak transvalvular pressure gradient both in the native and in the prosthetic valve. However, the increment was much steeper in the prosthetic valve. No significant differences in cardiac output were noted between the native and the prosthetic valves. The described pre-clinical porcine model was found suitable for site-specific in-vivo hemodynamic assessment of aortic valvular prosthesis without cardiopulmonary bypass
An Activin A/BMP2 chimera, AB215, blocks estrogen signaling via induction of ID proteins in breast cancer cells
Molecular diagnosis of hereditary spherocytosis by multi-gene target sequencing in Korea: matching with osmotic fragility test and presence of spherocyte
Background
Current diagnostic tests for hereditary spherocytosis (HS) focus on the detection of hemolysis or indirectly assessing defects of membrane protein, whereas direct methods to detect protein defects are complicated and difficult to implement. In the present study, we investigated the patterns of genetic variation associated with HS among patients clinically diagnosed with HS.
Methods
Multi-gene targeted sequencing of 43 genes (17 RBC membrane protein-encoding genes, 20 RBC enzyme-encoding genes, and six additional genes for the differential diagnosis) was performed using the Illumina HiSeq platform.
Results
Among 59 patients with HS, 50 (84.7%) had one or more significant variants in a RBC membrane protein-encoding genes. A total of 54 significant variants including 46 novel mutations were detected in six RBC membrane protein-encoding genes, with the highest number of variants found in SPTB (nโ=โ28), and followed by ANK1 (nโ=โ19), SLC4A1 (nโ=โ3), SPTA1 (nโ=โ2), EPB41 (nโ=โ1), and EPB42 (nโ=โ1). Concurrent mutations of genes encoding RBC enzymes (ALDOB, GAPDH, and GSR) were detected in three patients. UGT1A1 mutations were present in 24 patients (40.7%). Positive rate of osmotic fragility test was 86.8% among patients harboring HS-related gene mutations.
Conclusions
This constitutes the first large-scaled genetic study of Korean patients with HS. We demonstrated that multi-gene target sequencing is sensitive and feasible that can be used as a powerful tool for diagnosing HS. Considering the discrepancies of clinical and molecular diagnoses of HS, our findings suggest that molecular genetic analysis is required for accurate diagnosis of HS.Support was provided by: the National Research Foundation of Korea (NRF) grant funded by the Korea government(MSIT) (NRF-2017R1A2A1A17069780) http://www.nrf.re.kr/
Regular and Random Components in Aiming-Point Trajectory During Rifle Aiming and Shooting
The authors examined the kinematic qualities of the aiming trajectory as related to expertise. In all, 2 phases of the trajectory were discriminated. The first phase was regular approximation to the target accompanied by substantial fluctuations obeying the WeberโFechner law. During the first phase, shooters did not initiate the triggering despite any random closeness of the aiming point (AP) to the target. In the second phase, beginning at 0.6โ0.8 s before the trigger pull, shooters applied a different control strategy: They waited until the following random fluctuation brought the AP closer to the target and then initiated triggering. This strategy is tenable when sensitivity of perception is greater than precision of the motor action, and could be considered a case of stochastic resonance. The strategies that novices and experts used distinguished only in the values of parameters. The authors present an analytical model explaining the main properties of shooting
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