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To biomechanically investigate a novel modified all-suture construct compared with commercially available suspensory button fixation for stabilization of the syndesmosis.Eight matched pairs of cadaver lower limbs were obtained. We used a material testing machine (MTS) and Optotrak optoelectronic 3D motion measurement system for testing. Syndesmotic injuries were simulated, and specimens were fixed with either a suspensory suture button or modified all suture construct. Repaired specimens were then cyclically loaded for 500 cycles. Spatial relationship of the tibia and fibula were continuously monitored for the intact, destabilized, and repaired states. Results were analyzed using independent samples t test.There was no significant difference in sagittal or coronal plane translation between intact and either repair. Compared to the intact state, both repair techniques demonstrated significantly more external rotation of the fibula relative to the tibia, and decreased construct stiffness. Cycling of the specimens did not significantly increase coronal or sagittal plane translation, however external rotation of the fibula relative to the tibia increased and stiffness decreased with cycling for both repair techniques.Our data suggests that sagittal and coronal plane translation is no different from the intact state for both fixation techniques. However, rotation of the fibula relative to the tibia was increased and construct stiffness was decreased compared to the intact state for both fixation techniques. These findings suggest that an all-suture construct could offer syndesmotic fixation comparable to proprietary suspensory button fixation in a cadaver model.

The goal was to determine the effect of addition of oblique trajectory distal interlock screws to a retrograde intramedullary femoral nail on implant stability (stiffness), cycles to failure and mode of failure. The hypothesis was that addition of oblique screws would increase implant stability and number of loading cycles to failure.Eight matched pairs were tested; one femur implanted with a femoral nail with only transverse distal interlock screws and the other with transverse and oblique interlock screws. Axial compressive load was applied to the femoral head and the gluteal tendon was tensioned vertically to simulate standing or at 45° to the sagittal plane to simulate stair climbing. Loads were cycled to increasing amplitude until failure of fixation (10 mm displacement or 10° rotation).In simulated standing, oblique screw specimen had greater sagittal bending (bowing) than transverse only specimen. Transverse (axial) plane motion was higher in simulated stair climbing in oblique screw specimen. Oblique screw specimen had higher sagittal plane translation at 600 N of load. At 300 N, oblique screw specimen had lower internal-external rotation than transverse only specimen. A larger number of cycles to failure were observed in four oblique screw of seven paired specimen. Failure (10 mm or 10 degrees of motion) was only achieved during simulated stair climbing.Our hypothesis that adding oblique screws improves fixation was rejected. Activities of daily living other than standing may constitute a challenge to fracture fixation; fixation failure occurred at lower loads in simulated stair climbing than standing.

Background: Individual contributions of the rotator cuff (RC) and superior capsule (SC) to prevent superior translation of the humerus are not well understood. Purpose: To evaluate the relative contributions of the SC and RC to normal and pathologic shoulder biomechanics by determining their independent effects on superior humeral translation. Study Design: Controlled laboratory study. Methods: Twelve cadaveric shoulders were tested at 0º, 45º, and 90º of abduction under 5 conditions: intact RC/SC, RC sectioned first, SC sectioned first, both structures sectioned, and RC repair. Matched pairs were randomly assigned to the second or third testing condition (RC or SC sectioned first). Specimens were tested under 2 static conditions (40-N deltoid load [balanced load], 80-N deltoid load [superiorly directed load]) and 1 dynamic condition during active abduction. A mixed-design 2-way repeated-measures analysis of variance with Bonferroni adjustments was performed to compare testing conditions. Paired t tests were used to compare specimens in the intact state versus the repaired state. Significance was set at P < .05. Results: During balanced deltoid loading at 0° and 45º, there was significantly greater humeral translation when both structures were sectioned as compared with the intact state and with both isolated sectioned states ( P < .05 for all). No significant differences were observed between or within groups at 90º of abduction. These effects remained consistent with superiorly directed loading. Dynamic testing of both groups showed a significant increase in superior translation for specimens in which the RC was deficient versus the intact state ( P = .027), with no difference when the SC was sectioned. The RC repair state returned translation to values similar to the intact state at all abduction angles and loading conditions ( P > .05). Conclusion: In this cadaveric study, the SC and RC played an important role in preventing superior humeral translation; however, dynamic testing suggested preferential contribution of the RC. RC repair was effective in preventing superior humeral translation, even with a sectioned SC at the level of the glenohumeral joint. Clinical Relevance: RC repair was effective in preventing superior humeral translation, even in the presence of a sectioned SC at the level of the glenohumeral joint in this cadaveric model. Our data lay the groundwork for future studies investigating the clinical effect of RC repair in an SC sectioned state.

This paper provides insight into the design, analysis and operation of a cantilever beam resonator that is driven electrically. The beam is a bimorph structure with lead zirconate titanate (PZT) and aluminum layers. The PZT layer is electroded in segments to form a sensor and actuator pair for feedback to drive the resonator using a logic gate. A third passive segment is used to change the frequency of operation of the resonator. The study is based on an analytical model of the beam and experimental testing.

MRI allows non-invasive assessment of intervertebral disc degeneration with the added clinical benefit of using non-ionizing radiation. What has remained unclear is the relationship between assessed disc degeneration and lumbar spine kinematics. Kinematic outcomes of 54 multi-segment (L1-Sacrum) lumbar spine specimens were calculated to discover if such an underlying relationship exists with degeneration assessed using the Pfirrmann grading system. Further analyses were also conducted to determine if kinematic outcomes were affected by motion segment level, gender or applied compressive preload. Range of motion, hysteresis, high flexibility zone size and rotational stiffness in flexion-extension, lateral bending and axial rotation were the kinematic outcomes. Caudal intervertebral discs in our study sample were more degenerative than cranial discs. L5-S1 discs had the largest flexion-extension range of motion (p 0.005) and L1-L2 discs the lowest flexion high flexibility zone size (p 0.013). No other strict cranial-caudal differences in kinematic outcomes were found. Low flexibility zone rotational stiffness increased with disc degeneration grade in extension, lateral bending and axial rotation (p 0.001). Trends towards higher hysteresis and lower range of motion with increased degeneration were observed in flexion-extension and lateral bending. Applied compressive preload increased flexion-extension hysteresis and augmented the effect of degeneration on hysteresis (p 0.0005). Female specimens had about one degree larger range of motion in all rotational modes, and higher flexion extension hysteresis (p = 0.016). These results suggest that gender differences exist in lumbar spine kinematics. Additionally high disc loads, applied compressive preload or applied moment, are needed to kinematically distinguish discs with different levels of degeneration. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1389-1398, 2016.

Surveys on vectors, livestock diseases and socio-economic issues were undertaken in June and August 2005 in Kiboko area, Makueni District of Kenya. It was deemed that the information generated would help to understand the farmersf awareness of the extent of tsetse and trypanosomosis and other diseases within and around Kiboko ranch. Over 500 head of cattle belonging to KARI and surrounding small scale farms were screened for parasites . tick-borne, trypanosomes, helminths and ticks. The farmers who presented their animals were interviewed to generate the socio-economic data. Biconical traps deployed were baited with acetone and 8.4.1.phenol sachets. A total of 21 tsetse flies (6 in June and 15 in August) were caught. Veterinary records from the area indicated the commonest diseases to be anaplasmosis, trypanosomosis and non-specific pneumonia in cattle. The overall trypanosome point prevalence in phase I and II were 3.9% and 0 respectively. On a four-point scale stratification the abundance of tick infestation in Kiboko was clean to low (Clean = 0; low . 20) with the overall tick infestation prevalence of 28.2%. Results on helminth-faecal egg count ranged from 0 . 4000 epgs with a mean 74.64. Skin diseases, trypanosomosis and tick-borne diseases (TBDs) were mentioned by the respondents as the most important livestock diseases in proportions of 61%, 50% and 36%, respectively. From this investigation, despite livestock playing a key role in the economy of farmers around Kiboko ranch, their knowledge of livestock diseases and their management was found to be low. In conclusion, trypanosomosis and TBDs as well as their vectors are still constraints to livestock production.

The repellancy of essential oils of eight Lippia species on maize weevils was compared with NN-diethyltoluamide (DEET). The larvicidal activity of these essential oils was also examined. As a repellant, the essential oil of L. ukambensis (chemotype camphor) was the most active. Other promising repellants were the essential oils of L. javanica, L. dauensis, L. somalensis and L. grandifolia. The essential oil of L. wilmsii was the most active as a larvicide. Individual hydrocarbon monoterpene constituents were generally more active than the oxygenated constituents of the essential oils.

A custom program for the processing of pressure sensitive (Fuji) film data is presented and validated in this paper. Some of the shortcomings of previous descriptions of similar programs in literature are addressed. These shortcomings include incomplete descriptions of scan resolution, processing technique, and accuracy of results. Of these, the accuracy of results is the most important and is addressed in this study by using Fuji film calibration data. In Fuji film calibration, known loads are applied to forms with known area. The accuracy of this program and that of the two commercially available image processing programs were determined. The results of the custom program are found to be within 10% of the results from the commercial programs and from experimental data. This level of accuracy is the same reported level of accuracy of Fuji film, verifying the custom program for use in Fuji film contact pressure and area measurements.

Three steroidal indoxyls, 3-oxo-16,17-seco-16-nor-1,4-androstadien-15-(7\'-methoxy-2-indoxyliden)17-oic acid, 1-(2\'-indoxyliden)-2-nor-1,2-secocholestan-3-oic acid and 1-(5\'- chloro-2-indoxyliden)-2-nor-1,2-secocholestan-3-oic acid were synthesized and screened for anti-inflammatory activity. Their pKa values were also determined using a solubility method. The first compound, 3-oxo-16,17-seco-16-nor-1,4-androstadien-15-(7\'-methoxy-2-indoxyliden) 17-oic acid, had an ED50 value of 15.3 mg/kg and a pKa of 7.09. The cholestane derivative, 1-(2\'-indoxyliden)-2-nor-1,2-secocholestan-3-oic acid, and its chloro analogue 1-(5\'-chloro-2-indoxyliden)-2-nor-1,2-secocholestan-3-oic acid had ED50 values of 16.2 and 22.8 mg/kg, while their pKa values were 6.56 and 7.07, respectively, suggesting that these compounds are relatively weak acids. Keywords : Steroidal indoxyls, pKa values, anti-inflammatory The East and Central African Journal of Pharmaceutical Sciences Vol. 9 (2) 2006: pp. 52-57

The anti-inflammatory and antidiarrhoeal activities of 3β-Hydroxy-16, 17-seco-16-nor-5-androsten-15-(2-indoxyliden)-17-oic acid (I) are reported. After intraperitoneal administration, compound (I) gave an ED 50 of 9.5 mg/kg using the carrageenan induced rat paw oedema anti-inflammatory assay method. Indomethacin had an ED 50 of 5.8 mg/kg in this assay. Compound (I) and indomethacin caused comparable and dose-dependent varying degrees of delay in diarrhoea and also significantly reduced net colonic water flux into the colon of rats induced by castor oil. Key words: Steroidal Indoxyl, Anti-Inflammatory, Antidiarrhoeal. East and Central African Journal of Pharmaceutical Sciences Vol.6(2) 2003: 26-29

The estrogenic and anti-inflammatory activities of 3-methoxy-16, 17-seco-16-norestra-1,3,5-trien-15-(2'-indoxyliden)-17-oic acid is reported. After intraperitoneal administration, the dose of this compound required to reduce swelling of the rat paw by 50% (ED 50 ) was 14.1 mg/kg using the carrageenan-induced rat paw oedema anti-inflammatory assay method. Indomethacin had an ED 50 of 3.2 mg/kg in this assay while dexamethasone had an ED 50 of 1.7 mg/kg. The estrogenic activity of the compound after intramuscular administration in rats was 0.72 relative to diethylstilbestrol, when the two compounds were assayed at three dose levels of 1.0, 0.3 and 0.1 mg/kg. Key Words: Steroidal indoxyl, synthesis, estrogenic, anti-inflammatory East and Central African Journal of Pharmaceutical Sciences Vol.5(3) 2002: 44-48

This paper presents the design and analysis of a cantilever beam resonator that is driven by a piezoelectric material. In this paper, we shall look at the effects of miniaturizing the resonator. The beam is a bimorph structure with a Lead Zirconate Titanate (PZT) layer and a stainless steel substrate layer. The PZT layer is electroded in segments to form a sensor and actuator pair for feedback to drive the resonator. Key issues are the effects of design choices on the gain required to cause self-oscillation. These choices are placement and sizing of the sensor and actuator. The study is based on an analytical model of the beam. Results show that the gain required for self-oscillation is highly dependent on the actuator and sensor size and location, the mode of vibration and the overall resonator size.

This paper presents the design and analysis of a cantilever beam resonator that is driven by a piezoelectric material. The beam is a bimorph structure with Lead Zirconate Titanate (PZT) and stainless steel or aluminum layers. The PZT layer is electroded in segments to form a sensor and actuator pair for feedback to drive the resonator. An additional PZT segment is used, in conjunction with a capacitive shunt circuit, to change the vibration frequency of the resonator. The study is based on an analytical model of the beam and experimental testing.Copyright © 2003 by ASME

Myrica salicifolia Hoechst (Myricaceae) root extract was found to have analgesic activity in mice. In rats there was antipyretic but no antiinflammatory activity.

Field trips to herbalists' practices in an area about 200 miles around Nairobi (Kenya) enabled us to make a list of medicinal plant species preferentially used to treat malaria. Ajuga remota and Caesalpinia volkensii were further investigated as being the most frequently used species. Aqueous decoctions, ethanol macerates, and petroleum ether, methanol and water Soxhlet extracts of these plants were further tested for their in vitro antimalarial properties in a chloroquine sensitive (FCA/20GHA) and resistant (W2) strain of Plasmodium falciparum . The activity was assessed by the parasite lactate dehydrogenase (pLDH) assay method. There was a concentration-dependent inhibition by the vegetal extracts of both plants. The IC 50 of the most active A. remota extract (ethanol macerate) was 55 and 57 μg/ml against FCA/20GHA and W2, respectively. For C . volkensii , it was the Soxhlet-water extract which was most active against FCA/20GHA with an IC 50 of 404 μg/ml while the petroleum ether extract exhibited the most activity against W2 with an IC 50 of 250 μg/ml. Further phytochemical work is being done in order to identify the active principles.

This paper presents a model for a magnetorheological damper, and subsequent experimental results. Two cylindrical piston type MR dampers, which develop almost identical friction and viscous forces, were tested. These dampers were designed to provide different combinations of fluid flow and magnetic field orientation. In one damper, the magnetic field and magnetic field orientation are designed to be primarily parallel to each other, and in the other damper, the field and flow are designed to be perpendicular. Each actuator was tested under different conditions of applied current and piston speed, and the force-generating characteristics were studied. The two damper designs will be introduced and a comparison between results from the model and the experiments will be made. In general, the model captures the forcegenerating characteristics of the dampers; however, it does not account for field-flow orientations.

(-)-Cathinone and d-norpseudoephedrine (DNE) in the dose range 0.2-1.2 mg/ml produced a reduction in contractions of skeletal muscle, evoked by direct and indirect electrical stimulation and antagonised the facilitatory action of physostigmine on the neuromuscular junction; but failed to antagonise a partial blockade induced by d-tubocurarine (dTb) as occurs with norepinephrine or epinephrine. The local anaesthetic actions of (-)-cathinone and DNE were found to be almost equivalent to that of lignocaine. These results indicate that (-)-cathinone and DNE may have a direct blocking action on the neuromuscular junction, which is independent of cholinergic and adrenergic transmission.

A novel clerodane-type furano-diterpene with the 9,10-abeo-methyl group has been isolated from Croton megalocarpus as a major constituent. Structure elucidation has been achieved by a combination of spectroscopic measurements including 2D-NMR and NOE experiments, on the parent compound as well as the monoacetyl derivative. Lupeol, betulin, β-sitosterol and long-chain aliphatic esters were also found and characterized.