1. Action potentials of single plantaris motoneurons were recorded monophasically from fine ventral root filaments. A resistor was placed in shunt across the recording electrodes and its value was varied until the size of the action potentials was reduced by one-half. At this point the resistance of the filament was taken to be equal to that of the shunt, and the quotient of action-potential amplitude divided by filament resistance was proportional to the axonal action current. 2. The measurement of axonal action currents depends on the assumption that the filament-electrode system obeys Ohm's law. Tests were performed which validated this assumption. It was then shown that the axonal action currents varied as the square of conduction velocity over the range of alpha and gamma motoneurons. 3. A direct correlation was established between the critical firing levels of motoneurons and the sizes of the impulses in their axons after the recorded sizes had been normalized in accordance with the resistances of the ventral root filaments in which they were located. Since both the CFL and axonal diameter were related to impulse size, they were related to each other (Fig. 6). 4. Evidence is cited justifying the conclusion that the dimater of a motor axon is directly related to the size of its soma. Thus, it may be inferred that the critical firing level of a motoneuron is a function of its size.

OBJECTIVE

To compare radiation exposure and effective dose in children who underwent voiding cystourethrography (VCUG) performed with grid-controlled variable-rate pulsed fluoroscopy (GCPFL) with radiation exposure and effective dose in children who underwent VCUG performed with continuous fluoroscopy (CFL) and to compare these effective doses with those estimated with radionuclide cystography (RNC).

METHODS

Institutional review board approval was obtained, and the informed consent requirement was waived for this HIPAA-compliant retrospective study. Radiation exposure and fluoroscopy time during VCUG were reviewed in 145 children (75 girls, 70 boys; age range, 3 days to 8 years) who underwent GCPFL or CFL between 2001 and 2002. Children were grouped on the basis of the fluoroscopy unit used and their supine anteroposterior abdominal diameter (group 1, 8.0-8.5-cm diameter; group 2, 10-11-cm diameter; group 3, 12-13-cm diameter). Analysis of variance was used to compare radiation exposure and fluoroscopy time between fluoroscopy units and patient diameter groups. Effective doses were calculated and compared for both fluoroscopes and for estimated RNC dose values.

RESULTS

GCPFL resulted in a significant reduction in total radiation exposure, which was at least eight times lower than that with CFL in all three groups (P < .001 for all). There was no significant difference in fluoroscopy time (P>> .50). Effective radiation doses from GCPFL were approximately one order of magnitude lower than those from CFL but one order of magnitude higher than those from RNC.

CONCLUSIONS

In children, VCUG can be performed with a GCPFL unit that delivers radiation exposures that are at least eight times lower than those delivered by a conventional CFL unit.

BACKGROUND

http://radiology.rsnajnls.org/cgi/content/full/2492062066/DC1.

Ankle sprain injuries are the most common injury sustained during sporting activities. Three-quarters of ankle injuries involve the lateral ligamentous complex, comprised of the anterior talofibular ligament (ATFL), the calcaneofibular ligament (CFL), and the posterior talofibular ligament (PTFL). The most common mechanism of injury in lateral ankle sprains occurs with forced plantar flexion and inversion of the ankle as the body's center of gravity rolls over the ankle. The ATFL followed by the CFL are the most commonly injured ligaments. Eighty percent of acute ankle sprains make a full recovery with conservative management, while 20% of acute ankle sprains develop mechanical or functional instability, resulting in chronic ankle instability. Treatment of acute ankle sprains generally can be successfully managed with a short period of immobilization that is followed by functional rehabilitation. Patients with chronic ankle instability who fail functional rehabilitation are best treated with a Brostrom-Gould anatomic repair or, in those patients with poor tissue quality or undergoing revision surgery, an anatomic reconstruction.

Damage to the anterior talofibular ligament (ATFL) and cacaneofibular ligament (CFL) during an ankle sprain may be linked to the development of osteoarthritis. Although altered tibiotalar kinematics have been demonstrated, the effects of lateral ankle instability (LAI) on in vivo cartilage strains have not been described. We hypothesized that peak cartilage strains increase, and the location is shifted in patients with ATFL injuries. We used 3-D MRI models and biplanar fluoroscopy to evaluate in vivo cartilage contact strains in seven patients with unilateral LAI. Subjects had chronic unilateral ATFL injury or combined ATFL and CFL injury, and were evaluated with increasing load while stepping onto a force plate. Peak cartilage strain and the location of the peak strain were measured using the contralateral normal ankle as a control. Ankles with LAI demonstrated significantly increased peak strain when compared with ATFL-intact controls. For example, at 100% body weight, peak strain was 29+/-8% on the injured side compared to 21+/-5% on the intact side. The position of peak strain on the injured ankle also showed significant anterior translation and medial translation. At 100% body weight, the location of peak strain in the injured ankle translated anteriorly by 15.5+/-7.1mm and medially by 12.9+/-4.3mm relative to the intact ankle. These changes correspond to the region of clinically observed osteoarthritis. Chronic LAI, therefore, may contribute to the development of tibiotalar cartilage degeneration due to altered cartilage strains.

This study was designed to determine and describe precise anatomy of the lateral ankle ligaments and their relationship to adjacent osseous structures. This study was performed on 42 legs of 22 adult human embalmed cadavers. The lateral ankle ligaments were carefully dissected using a 2.5x surgical loupe. Mean values for the length, width and angle of the individual lateral ankle ligaments were measured. The precise location of insertion points and course of each ligament was observed and noted with ankle placed in neutral position. The anterior talofibular and calcaneofibular ligaments were coated with radio-opaque material. Radiographs were then taken in the anteroposterior, mortise and lateral projections. The anterior talofibular ligament (ATFL) was a flat, quadrilateral ligament and it made mean angle of 25 degrees (range 5 degrees -45 degrees ) with horizontal plane, and a mean angle of 47 degrees (range 45 degrees -56 degrees ) with sagittal plane. The posterior talofibular ligament was oriented in a nearly horizontal plane. Calcaneofibular ligament (CFL) was a flat oval ligament. It made a mean angle of 40 degrees (range 30 degrees -58 degrees ) with horizontal plane, and mean angle of 51 degrees (range 32 degrees -60 degrees ) with sagittal plane. The angle between CFL and ATFL was approximately 132 degrees (range 118 degrees -145 degrees ). These data provides important information for diagnosing injury and reconstructing lateral ankle ligaments.

We report the synthesis and self-assembly of amphiphilic, nonspherical, polymeric microparticles. Wedge-shaped particles bearing segregated hydrophilic and hydrophobic sections were synthesized in a microfludic channel by polymerizing across laminar coflowing streams of hydrophilic and hydrophobic polymers using continuous flow lithography (CFL). Particle monodispersity was characterized by measuring both the size of the particles formed and the extent of amphiphilicity. The coefficient of variation (COV) was found to be less than 2.5% in all measured dimensions. Particle structure was further characterized by measuring the curvature of the interface between the sections and the extent of cross-linking using FTIR spectroscopy. The amphiphilic particles were allowed to self-assemble in water or at water-oil interfaces. In water, the geometry of the particles enabled the formation of micelle-like structures, while in emulsions, the particles migrated to the oil-water interface and oriented themselves to minimize their surface energy.

Metastasis leads to the death of most cancer patients, and basal breast cancer is the most aggressive breast tumor type. Metastasis involves a complex cell migration process dependent on cytoskeletal remodeling such that targeting such remodeling in tumor cells could be clinically beneficial. Here we show that Hormonally Up-regulated Neu-associated Kinase (HUNK) is dramatically down-regulated in tumor samples and cell lines derived from basal breast cancers. Reconstitution of HUNK expression in basal breast cancer cell lines blocked actin polymerization and reduced cell motility, resulting in decreased metastases in two in vivo murine cancer models. Mechanistically, HUNK overexpression sustained the constitutive phosphorylation and inactivation of cofilin-1 (CFL-1), thereby blocking the incorporation of new actin monomers into actin filaments. HUNK reconstitution in basal breast cancer cell lines prevented protein phosphatase 2-A (PP2A), a phosphatase putatively acting on CFL-1, from binding to CFL-1. Our investigation of HUNK suggests that the interaction between PP2A and CFL-1 may be a target for antimetastasis therapy, particularly for basal breast cancers.

Conditional logistic regression is used for the analysis of binary outcomes when subjects are stratified into several subsets, e.g. matched pairs or blocks. Log odds ratio estimates are usually found by maximizing the conditional likelihood. This approach eliminates all strata-specific parameters by conditioning on the number of events within each stratum. However, in the analyses of both an animal experiment and a lung cancer case-control study, conditional maximum likelihood (CML) resulted in infinite odds ratio estimates and monotone likelihood. Estimation can be improved by using Cytel Inc.'s well-known LogXact software, which provides a median unbiased estimate and exact or mid-p confidence intervals. Here, we suggest and outline point and interval estimation based on maximization of a penalized conditional likelihood in the spirit of Firth's (Biometrika 1993; 80:27-38) bias correction method (CFL). We present comparative analyses of both studies, demonstrating some advantages of CFL over competitors. We report on a small-sample simulation study where CFL log odds ratio estimates were almost unbiased, whereas LogXact estimates showed some bias and CML estimates exhibited serious bias. Confidence intervals and tests based on the penalized conditional likelihood had close-to-nominal coverage rates and yielded highest power among all methods compared, respectively. Therefore, we propose CFL as an attractive solution to the stratified analysis of binary data, irrespective of the occurrence of monotone likelihood. A SAS program implementing CFL is available at: http://www.muw.ac.at/msi/biometrie/programs.

BACKGROUND

The short-term results of modified Brostrom procedures (MBP) have been satisfactory. However, the long-term results of anatomical reconstruction have been less frequently reported. We report on our long-term results in our patient group.

METHODS

Thirty patients with chronic ankle instability who were treated using the MBP without CFL reconstruction from March 1997 to June 1999 were evaluated retrospectively. This consecutive series of patients was comprised of 26 males and four females. The mean age of the patients at the time of operation was 23 years. The mean followup period was 10.6 years. Twenty-four of the 30 were high-level amateur or professional athletes. The operation procedure involved only ATFL imbrication with inferior extensor retinaculum (IER) reinforcement. Clinical outcomes were evaluated by reviewing clinical charts, retrospectively. Functional outcome scores were obtained using the Hamilton scale, a VAS, and AOFAS score at final followup visit, when each patient underwent a physical examination and stress radiography.

RESULTS

Mean AOFAS score was 91 and the mean VAS at final followup was 87. According to the Hamilton classification, 12 achieved an excellent result, 16 a good result, and two a fair result. Mean anterior translation values at final followup were 6.9 and 6.1 mm on ipsilateral and contralateral sides. Furthermore, mean talar tilt angles were 3.0 and 2.5 degrees for ipsilateral and contralateral sides. Twenty-eight of the 30 patients were restored to pre-injury activity levels.

CONCLUSIONS

The long-term surgical results of the MBP without CFL reconstruction for chronic lateral ankle instability were good to excellent in terms of functional, clinical, and radiographic assessments.

No final comprehensive hypothesis of the chain of events involved in inhibition of calcification can be constructed at the present time. The flow diagram in Figure 1 is presented only as a working hypothesis currently used by the authors. Insofar as the Cfl is representative of native factors at calcifying sites, none of the major theories on the nature of mineral formation at present seem excluded. As in the fields of clotting and complement pathways, where backup systems seem to operate, one should not be surprised if more than one system operates in cartilaginous calcification.

Selectins are essential for leukocyte recruitment in inflammation. Because of a lectin domain present in the selectin structure, we investigated the anti-inflammtory activity of six mannose-glucose binding lectins from brazilian beans: Dioclea guianensis-DguiL; D. grandiflora-DgL; Cratylia floribunda-CfL; D. violacea-D.vL; D. virgata-DvirL and Canavalia brasiliensis-ConBr. The lectins were injected intravenously (i.v.) into rats (0.1 and 1.0 mg/kg; 30 min before irritants) and its activities compared to E. coli endotoxin (LPS,30 mug/kg i.v.). Three lectins (DvL, CfL and DguiL), although less intense than LPS, inhibited the neutrophil migration induced by carrageenan (Cg, 300 mug) in a dose-dependent manner (0.1 and 1.0 mg/kg). DvL activity was reversed by 0.1 M alpha-D-methyl-mannoside (alpha-CH3), but not by 0.1 M alpha-D-galactose. The fMLP (44 ng)-induced neutrophil migration was also reduced by these lectins. Endotoxin contamination of lectin samples could be excluded since alpha-CH3 treatment reversed the DvL effect, but did not modify LPS inhibitory activity. Carrageenan (300 mug)-induced paw oedema was also reduced by LPS or lectin treatments. Conversely, none of the tested lectins inhibited dextran (Dex, 300 mug)-induced paw oedema, a classical leukocyte independent model, or zymosan (Zy, 1.0 mg)-induced peritonitis and paw oedema. LPS showed no effect upon Dex-induced paw oedema and barely reduced (25%) the oedematogenic effects of zymosan. As proposed for LPS, the lectin inhibitory activity was better observed on neutrophil-mediated inflammatory reactions. We speculate that the plant lectin antiinflammatory activity is probably due to a competitive blockage of a common leukocyte and/or endothelial selectin carbohydrate ligand.

BACKGROUND

Surgical management of ossification of the posterior longitudinal ligament (OPLL) is associated with complications. However, surgical complications for OPLL have not been clearly documented.

OBJECTIVE

To review and summarize the incidence of surgical complications of OPLL in the cervical spine and evaluate the impact of surgical approach (anterior or posterior), year of study publication, follow-up duration, and the surgical outcome on complication incidence.

METHODS

Systematic review.

METHODS

An English literature review was conducted especially on surgical complications of cervical OPLL. The incidence of complications was statistically summarized, with its correlation to surgical approaches, year of study publications, follow-up duration, and the surgical outcome was statistically evaluated.

RESULTS

Twenty-seven retrospective studies, including a total of 1,558 patients, were reviewed. The overall incidence of surgical complications of cervical OPLL was 21.8%. Neurologic deficit (8.3%, overall rate), cerebrospinal fluid leakage (CFL) (5.1%), axial pain (3.5%), and implant complications (3.5%) were relatively common. The incidence of complications for posterior approach was not statistically different from those for anterior procedures. However, with regard to individual complication, C5 palsy and axial pain occurred more frequently in patients approached posteriorly, whereas CFL, implant complications, hoarseness, dysphagia, and dyspnea appeared more common in anterior cases.

CONCLUSIONS

There is a relatively high incidence of surgical complications for cervical OPLL compared with other cervical degeneration diseases. It is, therefore, necessary for surgeons to take into consideration the risk of surgical complications when communicating with patients for decision making and to alert complications during or after surgical procedures.

The high intensity focused ultrasound (HIFU) and thermosensitive cerasomes (HTSCs) were successfully assembled by employing cerasome-forming lipid (CFL) in combination with the component lipids of conventional low temperature sensitive liposomes (LTSLs) including 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000] (DSPE-PEG-2000) and 1-stearoyl-2-hydroxy-sn-glycero-3-phosphocholine (MSPC). The HTSCs showed spherical shape with a mean diameter around 200 nm, exhibiting good biocompatibility. Both hydrophilic and lipophilic drugs can be efficiently encapsulated into HTSCs. In addition, the release rate of HTSCs could be conveniently adjusted by varying the molar ratios of CFL to DPPC. The drug loaded HTSCs showed much longer blood circulation time (half-life >8.50 ± 1.49 h) than conventional LTSLs (0.92 ± 0.17 h). An in vitro study demonstrated that the drug loaded HTSCs are highly stable at 37 °C and show a burst release at 42 °C, providing a capability to act synergistically against tumors. We found that the HTSCs with a proportion of 43.25% of CFL could release more than 90% hydrophilic drugs in 1 min at an elevated temperature of 42 °C generated by HIFU exposure. After intravenous injection of doxorubicin (DOX) loaded HTSCs at 5 mg DOX/kg, followed by double HIFU sonication, the tumor growth of the adenocarcinoma (MDA-MB-231) bearing mice could be significantly inhibited. Therefore, the drug loaded HTSCs combined with HIFU hold great potential for efficient local chemotherapy of cancer due to the ability to deliver high concentration of chemotherapy drugs directly to the tumor, achieve maximum therapeutic efficacy and minimal side effects, and avoid the damage to the healthy tissues caused by systemic administration of drugs.

BACKGROUND

Phototherapy is the mainstay of treatment of neonatal hyperbilirubinaemia. The commonly used light sources for providing phototherapy are special blue fluorescent tubes, compact fluorescent tubes and halogen spotlights. However, light emitting diodes (LEDs) as light sources with high luminous intensity, narrow wavelength band and higher delivered irradiance could make phototherapy more efficacious than the conventional phototherapy units.

OBJECTIVE

To evaluate the effect of LED phototherapy as compared to conventional phototherapy in decreasing serum total bilirubin levels and duration of treatment in neonates with unconjugated hyperbilirubinaemia.

METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library 2010, Issue 1), MEDLINE (1966 to April 30, 2010) and EMBASE (1988 to July 8, 2009). Handsearches of the proceedings of annual meetings of The European Society for Paediatric Research and The Society for Pediatric Research were conducted through 2010.

METHODS

Randomised or quasi-randomised controlled trials were eligible for inclusion if they enrolled neonates (term and preterm) with unconjugated hyperbilirubinaemia and compared LED phototherapy with other light sources (fluorescent tubes, compact fluorescent tubes, halogen spotlight; method of administration: conventional or fibreoptic).

METHODS

We used the standard methods of The Cochrane Collaboration and its Neonatal Review Group for data collection and analysis.

RESULTS

Six randomised controlled trials met the inclusion criteria for this review. Four studies compared LED and halogen light sources. Two studies compared LED and compact fluorescent light sources. The duration of phototherapy (six studies, 630 neonates) was comparable in LED and non-LED phototherapy groups (mean difference (hours) -0.43, 95% CI -1.91 to 1.05). The rate of decline of serum total bilirubin (STB) (four studies, 511 neonates) was also similar in the two groups (mean difference (mg/dL/hour) 0.01, 95% CI -0.02 to 0.04). Treatment failure, defined as the need of additional phototherapy or exchange blood transfusion (1 study, 272 neonates), was comparable (RR 1.83, 95% CI 0.47 to 7.17). Side effects of phototherapy such as hypothermia (RR 6.41, 95% CI 0.33 to 122.97), hyperthermia (RR 0.61, 95% CI 0.18 to 2.11) and skin rash (RR 1.83, 95% CI 0.17 to 19.96) were rare and occurred with similar frequency in the two groups.

CONCLUSIONS

LED light source phototherapy is efficacious in bringing down levels of serum total bilirubin at rates that are similar to phototherapy with conventional (compact fluorescent lamp (CFL) or halogen) light sources. Further studies are warranted for evaluating efficacy of LED phototherapy in neonates with haemolytic jaundice or in the presence of severe hyperbilirubinaemia (STB ≥ 20 mg/dL).

OBJECTIVE

To determine how central field loss (CFL) affects reaction time to pedestrians and to test the hypothesis that scotomas lateral to the preferred retinal locus will delay detection of hazards approaching from that side.

METHODS

Participants with binocular CFL (scotoma diameter, 7°-25°; visual acuity, 0.3-1.0 logMAR) using lateral preferred retinal fixation loci and matched controls with normal vision drove in a simulator for approximately 1½ hours per session for 2 sessions a week apart. Participants responded to frequent virtual pedestrians who appeared on either the left or right sides and approached the participant's lane on a collision trajectory that, therefore, caused them to remain in approximately the same area of the visual field.

RESULTS

The study included 11 individuals with CFL and 11 controls with normal vision. The CFL participants had more detection failures for pedestrians who appeared in areas of visual field loss than did controls in corresponding areas (6.4% vs 0.2%). Furthermore, the CFL participants reacted more slowly to pedestrians in blind than nonscotomatous areas (4.28 vs 2.43 seconds, P < .001) and overall had more late and missed responses than controls (29% vs 3%, P < .001). Scotoma size and contrast sensitivity predicted outcomes in blind and seeing areas, respectively. Visual acuity was not correlated with response measures.

CONCLUSIONS

In addition to causing visual acuity and contrast sensitivity loss, the central scotoma per se delayed hazard detection even though small eye movements could potentially compensate for the loss. Responses in nonscotomatous areas were also delayed, although to a lesser extent, possibly because of the eccentricity of fixation. Our findings will help practitioners advise patients with CFL about specific difficulties they may face when driving.

BACKGROUND

We describe the topographic anatomy of the lateral ligament complex of the ankle using 3-dimensional (3D) computed tomography (CT) imaging.

METHODS

Dissection of the anterior talofibular ligament (ATFL) and the calcaneofibular ligament (CFL) was performed on 8 unpaired fresh-frozen cadaver feet. Ligaments were sharply dissected from bone, and the footprint was outlined with radio-opaque paint. The specimen underwent a 0.625-mm slice CT scan of the ankle with 3D reconstructions. Software was used to determine the surface area of the ligament footprint as well as measure the distance from the peroneal tubercle to the center of the CFL footprint. Data are presented as mean ± standard error.

RESULTS

Six specimens had a bifid ATFL. Seven ankles had a bifid ATFL footprint on the talus. All specimens had intact CFL fibers. The intact superior and inferior limbs of the ATFL measured 19.7 ± 1.2 mm and 16.7 ± 1.1 mm. The CFL measured 24.8 ± 2.4 mm. The area of the footprints of the superior ATFL and inferior ATFL on the talus measured 1.5 ± 0.26 cm(2) and 0.90 ± 0.07 cm(2). The CFL and ATFL origins on the fibula were continuous and measured 3.48 ± 0.39 cm(2). The CFL insertion on the calcaneus measured 2.68 ± 0.20 cm(2). The CFL was found 27.1 ± 1.0 mm posterior and superior from the peroneal tubercle.

CONCLUSIONS

In presumably uninjured specimens, both the ATFL and its footprint on the talus were bifid. The CFL and ATFL origins have a single confluent footprint on the anterior border of the distal fibula. The CFL footprint on the calcaneus is almost 3 cm posterior and superior to the peroneal tubercle.

CONCLUSIONS

This study may assist surgeons in anatomically reconstructing the lateral ligament complex of the ankle.

BACKGROUND

Light-emitting diodes (LEDs) deliver higher levels of blue light to the retina than do conventional domestic light sources. Chronic exposure to high-intensity light (2,000-10,000 lux) has previously been found to result in light-induced retinal injury, but chronic exposure to relatively low-intensity (750 lux) light has not been previously assessed with LEDs in a rodent model.

OBJECTIVE

We examined LED-induced retinal neuronal cell damage in the Sprague-Dawley rat using functional, histological, and biochemical measurements.

METHODS

We used blue LEDs (460 nm) and full-spectrum white LEDs, coupled with matching compact fluorescent lights, for exposures. Pathological examinations included electroretinogram, hematoxylin and eosin (H&E) staining, immunohistochemistry (IHC), and transmission electron microscopy (TEM). We also measured free radical production in the retina to determine the oxidative stress level.

RESULTS

H&E staining and TEM revealed apoptosis and necrosis of photoreceptors, which indicated blue-light induced photochemical injury of the retina. Free radical production in the retina was increased in LED-exposed groups. IHC staining demonstrated that oxidative stress was associated with retinal injury. Although we found serious retinal light injury in LED groups, the compact fluorescent lamp (CFL) groups showed moderate to mild injury.

CONCLUSIONS

Our results raise questions about adverse effects on the retina from chronic exposure to LED light compared with other light sources that have less blue light. Thus, we suggest a precautionary approach with regard to the use of blue-rich "white" LEDs for general lighting.

BACKGROUND

Shang YM, Wang GS, Sliney D, Yang CH, Lee LL. 2014. White light-emitting diodes (LEDs) at domestic lighting levels and retinal injury in a rat model. Environ Health Perspect 122:269-276; http://dx.doi.org/10.1289/ehp.1307294.

We analyzed the changes in lateral ligament forces during anterior drawer and talar tilt testing and examined ankle joint motion during testing, following an isolated lesion of the anterior talofibular ligament (ATFL) or a combined lesion of the ATFL and calcaneofibular ligament (CFL). 8 cadaver specimens were held in a specially designed testing apparatus in which the ankle position (dorsiflexion-plantarflexion and supination-pronation) could be varied in a controlled manner. Ligament forces were measured with buckle transducers, and joint motion was measured with an instrumented spatial linkage. An anterior drawer test was performed using an 80 N anterior translating force, and a talar tilt test was performed using a 5.7 Nm supination torque with intact ligaments, after sectioning of the ATFL, and again after sectioning of the CFL. The tests were repeated at 10 degrees dorsiflexion, neutral, and 10 degrees and 20 degrees plantarflexion. In the intact ankle, the largest increases in ATFL force were observed during testing in plantarflexion, whereas the largest increases in CFL force were observed in dorsiflexion. Isolated ATFL injury caused only small laxity changes, but a pronounced increase in laxity was observed after a combined CFL and ATFL injury.

The actin depolymerizing factor (ADF)/cofilin protein family is essential for actin dynamics, cell division, chemotaxis and tumor metastasis. Cofilin-1 (CFL-1) is a primary non-muscle isoform of the ADF/cofilin protein family accelerating the actin filamental turnover in vitro and in vivo. In response to environmental stimulation, CFL-1 enters the nucleus to regulate the actin dynamics. Although the purpose of this cytoplasm-nucleus transition remains unclear, it is speculated that the interaction between CFL-1 and DNA may influence various biological responses, including DNA damage repair. In this review, we will discuss the possible involvement of CFL-1 in DNA damage responses (DDR) induced by ionizing radiation (IR), and the implications for cancer radiotherapy.

Subjects with central field loss (CFL) individually selected enhancement parameters to improve visibility of static video images. The effect of enhancement on performance and on perceived quality of motion video was assessed. Performance, e.g. recognition of visual details, was assessed by having subjects answer questions regarding visual information contained in the video motion segments that were enhanced using the individually-selected parameters. Enhancement did not improve subject performance on questions about video content. This result might be due to a ceiling effect limitation of the performance assessment method. In a second procedure, subjects' continuous perceptions of quality (using an adjective-based rating scale) were made while the enhancement parameters were abruptly switched among multiple values; these included the individually-selected enhancements, as well as unenhanced, over-enhanced, and degraded segments. The results indicate that adaptive enhancement (individually-tuned using a static image) adds significantly to perceived image quality when viewing motion video. Subjects who selected stronger contrast enhancement also perceived the enhancement to provide a larger benefit in image quality.

BACKGROUND

Clinical assessment of syndesmotic injury usually consists of two tests: the ankle external rotation test and squeeze test. This study sought to determine the sensitivity and specificity of both for syndesmotic injury secondary to lateral ankle sprain.

METHODS

Fifty-six patients with sprained ankles underwent clinical examination for syndesmotic injury with the aforementioned tests. Clinical findings were compared against magnetic resonance imaging (MRI) of the ankle. Sprains were graded on anatomical and functional classification scales, and correlation and agreement between both scales were assessed.

RESULTS

The MRI prevalence of syndesmotic injury in patients with lateral ankle sprains was 17.8%. Sensitivity and specificity were 30% and 93.5% for the squeeze test, and 20% and 84.8% for the external rotation test, respectively. Using the anatomical scale for sprain grading, 40% of syndesmotic injuries occurred in Grade I, 40% in Grade II, and 20% in Grade III sprains. Ten percent of patients with syndesmotic injury had no lateral ligament injury on MRI, 70% had injury of the anterior talofibular (ATFL) ligament, and 20% had injury to the ATFL and calcaneofibular (CFL).

CONCLUSIONS

The sensitivity of the squeeze test and external rotation test was low, suggesting that physical examination often fails to diagnose syndesmotic injury. Conversely, specificity was very high; nearly all patients with a positive test actually had syndesmotic injury. Severity of ankle sprain was not associated with prevalence of syndesmotic injury.

OBJECTIVE

The aim of this study was to determine static load-bearing capacity and compressive fatigue limits (CFL) of laboratory particulate filler composite resin (PFC) with three different types of fiber-reinforced composite (FRC) substructures.

METHODS

A total of 420 test specimens were prepared having 1.0mm of FRC layer as substructure (short random, continuous unidirectional and bidirectional fiber orientations), and a 2.0-mm thick surface layer of PFC. Control specimens were prepared from plain FRC or PFC. The specimens (n=15) were either dry stored or water stored (37 degrees C for 2 weeks) before they were loaded with a steel ball (Ø 3.0mm) under static load until fracture and cyclic load with maximum controlled regimen following a staircase approach with maximum 10(3) cycles. The decrease in CFL compared to static load was calculated and data were analyzed using ANOVA and Weibull statistics.

RESULTS

The highest static loads were registered for plain FRC specimens [short random 1842 N(205), continuous bidirectional 2258 N(233) and unidirectional fiber orientation 538 N(254)]. The specimens with FRC substructure and PFC coverage gave load values of 1517 N(249), 1670 N(241) and 677 N(240), respectively. The specimens made of PFC only, failed with 1047 N(230) load. The CFL for 10(3) cycles ranged between 19 and 39% of the static load values. ANOVA revealed that all factors significantly affected the load bearing capacity (p<0.001).

CONCLUSIONS

The results suggested that the material combination of continuous bidirectional or random FRC and PFC, gave higher CFL and static load-bearing capacity than that obtained with plain particulate filler composite resin.

A level-set method is developed for the numerical minimization of a class of Had-wiger valuations with a potential on a set of three-dimensional bodies. Such valuations are linear combinations of the volume, surface area, and surface integral of mean curvature. The potential increases rapidly as the body shrinks beyond a critical size. The combination of the Hadwiger valuation and the potential is the mean-field free-energy functional of the solvation of non-polar molecules in the recently developed variational implicit-solvent model. This functional of surfaces is minimized by the level-set evolution in the steepest decent of the free energy. The normal velocity of this surface evolution consists of both the mean and Gaussian curvatures, and a lower-order, "forcing" term arising from the potential. The forward Euler method is used to discretize the time derivative with a dynamic time stepping that satisfies a CFL condition. The normal velocity is decomposed into two parts. The first part consists of both the mean and Gaussian curvature terms. It is of parabolic type with parameter correction, and is discretized by central differencing. The second part has all the lower-order terms. It is of hyperbolic type, and is discretized by an upwinding scheme. New techniques of local level-set method and numerical integration are developed. Numerical tests demonstrate a second-order convergence of the method. Examples of application to the modeling of molecular solvation are presented.

Skeletal muscle is a highly organized tissue in which the extracellular matrix (ECM) is composed of highly-aligned cables of collagen with nanoscale feature sizes, and provides structural and functional support to muscle fibers. As such, the transplantation of disorganized tissues or the direct injection of cells into muscles for regenerative therapy often results in suboptimal functional improvement due to a failure to integrate with native tissue properly. Here, we present a simple method in which biodegradable, biomimetic substrates with precisely controlled nanotopography were fabricated using solvent-assisted capillary force lithography (CFL) and were able to induce the proper development and differentiation of primary mononucleated cells to form mature muscle patches. Cells cultured on these nanopatterned substrates were highly-aligned and elongated, and formed more mature myotubes as evidenced by up-regulated expression of the myogenic regulatory factors Myf5, MyoD and myogenin (MyoG). When transplanted into mdx mice models for Duchenne muscular dystrophy (DMD), the proposed muscle patches led to the formation of a significantly greater number of dystrophin-positive muscle fibers, indicating that dystrophin replacement and myogenesis is achievable in vivo with this approach. These results demonstrate the feasibility of utilizing biomimetic substrates not only as platforms for studying the influences of the ECM on skeletal muscle function and maturation, but also to create transplantable muscle cell patches for the treatment of chronic and acute muscle diseases or injuries.