The Effects of an Integrated Exercise Program on Lower Extremity Biomechanics in Females with Medial Knee Displacement

Knee injury prevention exercise programs are aimed to correct knee valgus alignment during functional activities. Various factors are associated with knee valgus, including altered flexibility, muscle strength, and neuromuscular factors. However, the exercise programs that were used in previous studies did not consider these factors, which may have resulted in inconsistent finding. In addition, although lower extremity bony alignment has been associated with faulty movement patterns, little is known whether the bony alignment abnormalities influence individual's response to the exercise program. Lastly, effectiveness of exercise program was tested within the tasks that were part of the exercise program; therefore, it is unclear if improvement in the trained task transfers to untrained task. The purpose of this investigation was to examine the effects of an integrated exercise program on lower extremity biomechanics while accounting for bony alignment measures in females displaying high risk movement pattern. Thirty-two active females completed the study and randomly assigned to either the integrated exercise program group (INT=17, Age=21.0±3.1 yrs, Ht=161.1±5.0 cm, Mass=63.6±8.4 Kg) or the control group (CON=15, Age=20.8±3.0, Ht=162.3 ± 7.8 cm, Mass = 64.9± 18.9 Kg). The participants in the INT group went on a 6-week exercise training. Lower extremity joint range of motion, muscle strength, and hip, knee, and ankle kinetics and moment during the double-leg squat, single-leg squat, jump-landing, and running were assessed before and post-training. The frontal plane knee kinematics was improved during the single-leg squat, jump-landing, and running tasks following the intervention (p<0.05). These improvements were influenced by combined effects of bony alignments as greater femoral antetorsion, external tibial rotation while the magnitude of change was small. Peak knee valgus moment was also improved during the jump-landing task (p<0.05). The results indicate that the exercise program utilized in this study is effective in improving frontal plane knee kinematics in females present with knee valgus during the jump-landing, single-leg squat, and running tasks while no improvements were observed during the double-leg squat. This study also demonstrated motor learning transfer as frontal plane knee kinematics during running improved while this task was not a part of the exercise program during intervention.Doctor of Philosoph

Trunk and Lower Extremity Kinematics During Stair Descent in Women With or Without Patellofemoral Pain

Context: There is limited evidence indicating the contribution of trunk kinematics to patellofemoral pain (PFP). A better understanding of the interaction between trunk and lower extremity kinematics in this population may provide new avenues for interventions to treat PFP. Objective: To compare trunk and lower extremity kinematics between participants with PFP and healthy controls during a stair-descent task. Design: Cross-sectional study. Setting: Research laboratory. Patients or Other Participants: Twenty women with PFP (age = 22.2 +/- 3.1 years, height = 164.5 +/- 9.2 cm, mass = 63.5 +/- 13.6 kg) and 20 healthy women (age = 21.0 +/- 2.6 years, height = 164.5 +/- 7.1 cm, mass = 63.8 +/- 12.7 kg). Intervention(s): Kinematics were recorded as participants performed stair descent at a controlled velocity. Main Outcome Measure(s): Three-dimensional joint displacement of the trunk, hip, and knee during the stance phase of stair descent for the affected leg was measured using a 7-camera infrared optical motion-capture system. Pretest and posttest pain were assessed using a visual analogue scale. Kinematic differences between groups were determined using independent-samples t tests. A 2 3 2 mixed-model analysis of variance (group = PFP, control; time = pretest, posttest) was used to compare knee pain. Results: We observed greater knee internal-rotation displacement for the PFP group (12.8 degrees +/- 7.2 degrees) as compared with the control group (8.9 degrees +/- 4.4 degrees). No other between-groups differences were observed for the trunk, hip, or other knee variables. Conclusions: We observed no difference in trunk kinematics between groups but did note differences in knee internalrotation displacement. These findings contribute to the current knowledge of altered movement in those with PFP and provide direction for exercise interventions

Female Adolescent Soccer Players Utilize Different Neuromuscular Strategies Between Limbs During the Propulsion Phase of a Lateral Vertical Jump

# Background Multiplanar dynamic stability is an important unilateral function in soccer performance but has been scarcely examined in female soccer players. The lateral vertical jump task assesses unilateral functional performance, and energy generation contribution examines how each joint (hip, knee, ankle) contributes to the vertical component of the vertical jump phase to measure inter- and intra-limb differences. # Purpose To examine dominant versus non-dominant limb performance using energy generation contribution of the hip, knee, and ankle during the vertical jump component of the lateral vertical jump. # Study Design Cross-sectional observational study. # Methods Seventeen healthy, adolescent female soccer players (age 13.4±1.7 years; height 160.6±6.0 cm; mass 53.1±8.2 kg) participated. Quadriceps strength was measured via isokinetic dynamometry. Energy generation contribution (measured from maximal knee flexion to toe off) and vertical jump height were measured during the vertical component of the lateral vertical jump. # Results There was no significant difference between limbs for quadriceps strength (p=0.64), jump height (p=0.59), or ankle energy generation contribution (p=0.38). Energy generation contribution was significantly greater in the dominant hip (dominant 29.7±8.6%, non-dominant 18.4±6.3%, p\<0.001) and non-dominant knee (dominant 22.8±6.8%, non-dominant 36.2±8.5%, p\<0.001). # Conclusion High demand on coordination and motor control during the lateral vertical jump and inherent limb dominance may explain different intra-limb strategies for task performance despite jump height symmetry. Non-dominant affinity for stability and dominant compensatory performance may neutralize potential asymmetries. Implications for symmetry in observable outcomes such as jump height must consider underlying internal asymmetries. # Levels of Evidence 3B # Clinical Relevance Symmetrical findings on functional tasks have underlying internal asymmetries observed here in female adolescent soccer players. The lateral vertical jump may highlight these internal asymmetries (hip- versus knee-dominant movement strategies) due to the high coordinative demand to perform the task. Clinicians should be cognizant of underlying, potentially inherent, asymmetries even when observing functional symmetry in a task. # What is known about the subject Female adolescent soccer players are a high-risk cohort for sustaining anterior cruciate ligament injuries. Limb dominance may play a role in the performance of functional tasks, and limb dominance in soccer players is quite specialized: the dominant limb is the preferred kicking limb, while the non-dominant limb is the preferred stabilizing limb (plant leg). Functional performance in female soccer players has been studied in kicking, dribbling, sprinting, change of direction, and jumping -- however, these tasks were measured independent of limb dominance. It remains to be seen how unilateral functional tasks may be affected by limb dominance in female adolescent soccer players. # What this study adds to existing knowledge This study provides data on functional performance relative to limb dominance in female adolescent soccer players, and captures the lateral vertical jump task in both inter- and intra-limb measures. This highlights that intra-limb strategies to perform a coordinated motor task may be different between limbs, herein attributed to limb dominance. Even if gross motor outputs between limbs are symmetrical (i.e. jump height), the underlying movement strategies to achieve that output may be different (hip- versus knee-dominant movement strategies). These findings are important to research on functional performance measures related to attaining between-limb symmetry, as measures of energy generation contribution open the door for a more thorough understanding of joint-by-joint intra-limb contributions during a functional task

Closed Factorization

A closed string is a string with a proper substring that occurs in the string as a prefix and a suffix, but not elsewhere. Closed strings were introduced by Fici (Proc. WORDS, 2011) as objects of combinatorial interest in the study of Trapezoidal and Sturmian words. In this paper we present algorithms for computing closed factors (substrings) in strings. First, we consider the problem of greedily factorizing a string into a sequence of longest closed factors. We describe an algorithm for this problem that uses linear time and space. We then consider the related problem of computing, for every position in the string, the longest closed factor starting at that position. We describe a simple algorithm for the problem that runs in O(nlogn/loglogn) time, where n is the length of the string. This also leads to an algorithm to compute the maximal closed factor containing (i.e. covering) each position in the string in O(n log n/ log log n) time. We also present linear time algorithms to factorize a string into a sequence of shortest closed factors of length at least two, to compute the shortest closed factor of length at least two starting at each position of the string, and to compute a minimal closed factor of length at least two containing each position of the string

Trunk and Lower Extremity Kinematics During Stair Descent in Women With or Without Patellofemoral Pain

There is limited evidence indicating the contribution of trunk kinematics to patellofemoral pain (PFP). A better understanding of the interaction between trunk and lower extremity kinematics in this population may provide new avenues for interventions to treat PFP

Twelve-Week Quadriceps Strength as A Predictor of Quadriceps Strength At Time Of Return To Sport Testing Following Bone-Patellar Tendon-Bone Autograft Anterior Cruciate Ligament Reconstruction

# Background Restoration of quadriceps strength following anterior cruciate ligament reconstruction (ACL-R) continues to challenge both patients and clinicians. Failure to adequately restore quadriceps strength has been linked to decreased patients’ self-reported outcomes and an increased risk for re-injury. Early identification of quadriceps strength deficits may assist in tailoring early interventions to better address impairments. # Purpose The purpose of this study was to assess the relationship between early (12 weeks following ACL-R) isokinetic peak torque and isokinetic peak torque at time of return to sport (RTS) testing. # Study Design Cohort Study # Methods A total of 120 participants (males = 55; females =65) were enrolled in the study (age = 16.1±1.4 yrs; height = 1.72±10.5 m; mass = 70.7±16.3 kg). All participants were level 1 or 2 cutting and pivoting sport athletes who underwent a primary bone-patellar tendon-bone autograft ACL-R. Participants were tested at two time points: 12 weeks following surgery and again at time of RTS testing. A linear regression model was carried out to investigate the relationship between age, sex, and isokinetic peak torque at 12 weeks following ACL-R and isokinetic peak torque at time of RTS testing. # Results When 12-week isokinetic peak torque was entered first for the hierarchy regression analysis, this factor was predictive of the peak torque at the time of RTS testing, *F*(1, 118) = 105.6, *p* < 0.001, *R*^2^ = 0.472, indicating that the 12-week quadriceps strength accounted for 47% of the variance in the quadriceps strength at the time of RTS testing. When age and sex were added in the regression analysis, both factors only added 0.8% of variance for the quadriceps strength at the time of RTS testing. # Conclusion Isokinetic peak torque at 12 weeks following surgery was shown to be a significantly strong predictor (47%) for isokinetic quadriceps strength recovery at time of RTS. This finding underscores the importance of early restoration of quadriceps strength and that while non-modifiable factors such as sex and age are important, early restoration of quadriceps strength most strongly influences late stage quadriceps strength. # Level of Evidence

Dietary intake, mental status, physical activity, and lifestyle affecting bowel movement frequency and stool texture in young Japanese women

Constipation is a symptom-based disorder, and its definition is mainly subjective. Patients are more concerned with ease ofpassage and consistency rather than frequency of bowel movement. Studies on bowel movement frequency and stool texture inthe general population are sparse, especially in young women. In this cross-sectional study, data obtained from self-administered questionnaires, including age, height, body weight, lifestyle, food habits, anxiety, depressive status, frequency of bowel movements,stool texture, and defecation-related symptoms were analyzed in 245 female Japanese university students. An establishedsemiquantitative questionnaire available for clinical investigation (FFQg) was used to obtain a detailed assessment of food intake and physical activity levels. Of the participants, 21.4% had bowel movements ?3 times per week and 33.3% had hard or lumpy stools ?25% and loose (mushy) or watery stools <25% of bowel movements. There was a positive association between infrequent bowel movements and hard or lumpy stools. These two situations both caused similar symptoms such as a sensation of incomplete evacuation and straining. There was no association of bowel movement frequency and stool texture with any specificnutrients and foods, dietary intake, mental status, or physical activity. Several lifestyle factors such as regular bowel movements and hesitation with evacuation were associated with bowel movement frequency and stool texture. Several lifestyle factors, but not mental, physical, or dietary intake factors, were associated with bowel movement frequency and stool texture in young Japanese women

Enhanced transgene expression from chromatinized plasmid DNA in mouse liver

Plasmid DNA was chromatinized with core histones (H2A, H2B, H3, and H4) in vitro and was delivered into mouse liver by hydrodynamics-based administration. Transgene expression from the chromatinized plasmid DNA was more efficient than that from plasmid DNA delivered in the naked form. The use of acetylation-enriched histones isolated from cells treated with a histone deacetylase inhibitor (trichostatin A) seemed to be more effective. These results indicated that chromatinized plasmid DNA is useful for efficient transgene expression in vivo

N-Glycosylation of extracellular matrix protein 1 (ECM1) regulates its secretion, which is unrelated to lipoid proteinosis

Extracellular matrix protein 1 (ECM1) is expressed in a wide variety of tissues and plays important roles in extracellular matrix formation. Additionally, ECM1 gene mutations cause lipoid proteinosis (LP), a rare skin condition of genetic origin. However, an effective therapeutic approach of LP is not established. Here, we showed that ECM1 gene mutation observed in LP patients significantly suppresses its secretion. As ECM1 has three putative N-glycosylation sites and most of mutated ECM1 observed in LP patients are defective in these N-glycosylation sites, we investigated the correlation between LP and N-glycosylation of ECM1. We identified that the Asn354 and Asn444 residues in ECM1 were N-glycosylated by mass spectrometry analysis. In addition, an N-linked glycan at Asn354 negatively regulated secretion of ECM1, contrary to LP patient-derived mutants. These results indicate that the defect of N-glycosylation in ECM1 is not involved in the aberration of secretion of LP-derived mutated ECM1

N-glycosylation is required for secretion and enzymatic activity of human hyaluronidase1

Hyaluronidase1 (HYAL1) is a hydrolytic enzyme that degrades hyaluronic acid (HA) and has three predicted N-glycosylation sites at Asn99, Asn216, and Asn350. In this report, we show the functional significance of N-glycosylation on HYAL1 functions. Using mass spectrometry, we demonstrated that HYAL1 was N-glycosylated at the three asparagine residues. N-glycosylation of HYAL1 is important for secretion of HYAL1, as demonstrated by site-directed mutation. Moreover, a defect of N-glycosylation attenuated the enzymatic activity of HYAL1. Thus, HYAL1 is N-glycosylated at the three asparagine residues, and its secretion and enzymatic activity are regulated by N-glycosylation