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PubMed2006

[Preparation of Shuxiong micropellets by centrifugal granulation technology].

OBJECTIVE: To prepare shuxiong micropellets. METHOD: Shuxiong micropellets were prepared by using a centrifugal granulator. The formulation composition and process factors were optimized investigated by adopting several indices such as size distribution, repose angle, bulk density and friability as indexes. RESULT: The optimal process parameters were as follows. The ratio of fine intermediate product and MCC was 3:1 (w/w), the adhesive agent was 3% HMPC solution, the rotating rate of plate was 200 r x min(-1), the blower rate was 15 x 20 L x min(-1), the rate of air flow was 15 L x min(-1), the spray air pressure was 0.5 MPa, the rotating of spray solution pump was 5-25 r x min(-1) and the rotating rate of powder feed machine was 5-25 r x min(-1). CONCLUSION: Under the optimal conditions, micropellets prepared by using centrifugal granulator hadpossessed prefect shape and surface characteristics and the yield of shuxiong pellets was 90.5%.

Carthamus tinctorius↗

PubMed2000

Comparison of three-dimensional fast spin echo and gradient echo sequences for high-resolution temporal bone imaging.

T2-weighted high-resolution gradient and fast spin echo sequences are widely used as an alternative or adjunct to contrast-enhanced T1-weighted temporal bone imaging. However, to date no systematic comparison has been presented. The purpose of this work is to identify optimal acquisition parameters and to compare volume gradient and fast spin echo techniques. Signal intensities and scan efficiency were computed for gradient echo segment-interleaved motion-compensated acquisition into steady state (SIMCAST), standard fast spin echo (FSE), and fast recovery fast spin echo (FR-FSE). Computations were compared with inner ear images acquired with cubic voxel sizes of 0.35-0.40 mm(3)in 5-8 minutes. Given otherwise identical conditions, the FR-FSE sequence produces images with improved SNR in shorter scan times than standard FSE. For FR-FSE, the scan efficiency is optimal for specific pairs of TR and echo train length, eg, 400 ms/8, 735 ms/16, and 2,050 ms/48. FR-FSE images with large TR and echo trains, while achieving better SNR, are severely compromised by blurring. Imaging with echo train lengths of 16-24 and TR of 800-1,200 ms is a good compromise, and FR-FSE signal-to-noise ratio (SNR) and scan efficiency become comparable to SIMCAST. In vivo image quality is excellent with both FR-FSE and SIMCAST, but SIMCAST images have slightly higher SNR and are significantly more crisp. J. Magn. Reson. Imaging 2000;12:814-825.

Adult↗

PubMed1995

A comparison of conventional 'forward planning' with inverse planning for 3D conformal radiotherapy of the prostate.

A radiotherapy treatment plan optimisation algorithm has been applied to 48 prostate plans and the results compared with those of an experienced human planner. Twelve patients were used in the study, and 3-, 4-, 6- and 8-field plans (with standard coplanar beam angles for each plan type) were optimised by both the human planner and the optimisation algorithm. The human planner 'optimised' the plan by conventional forward planning techniques. The optimisation algorithm was based on fast simulated annealing using a cost-function designed to achieve a homogenous dose in the 'planning-target-volume' and to minimise the integral dose to the organs at risk. 'Importance factors' assigned to different regions of the patient provide a method for controlling the algorithm, and it was found that the same values gave good results for almost all plans. A study of the convergence of the algorithm is presented and optimal convergence parameters are determined. The plans were compared on the basis of both dose statistics and 'normal-tissue-complication-probability' (NTCP) and 'tumour-control-probability' (TCP). The results of the comparison study show that the optimisation algorithm yielded results that were at least as good as the human planner for all plan types, and on the whole slightly better. A study of the beam-weights chosen by the optimisation algorithm and the planner revealed differences that increased with the number of beams in the plan. The planner was found to make small perturbations about a conceived optimal beam-weight set. The optimisation algorithm showed much greater showed much greater variation, in response to individual patient geometry, frequently deselecting certain beams altogether from the plan. The algorithm is shown to be a useful tool for radiotherapy treatment planning. For simple (e.g., three-field) plans it was found to consistently achieve slightly higher TCP and lower NTCP values. For more complicated (e.g., eight-field) plans the optimisation also achieved slightly better results with generally less numbers of beams, unfavourable beams being deselected from the plan. Probably the greatest benefit is the reduced time taken by the optimisation to compute optimised beam-weights. This time always < or = 5 min; a factor of up to 20-times faster than the human planner.

Algorithms↗

PubMed2005

Synthetic scaffold morphology controls human dermal connective tissue formation.

Engineering tissues in bioreactors is often hampered by disproportionate tissue formation at the surface of scaffolds. This hinders nutrient flow and retards cell proliferation and tissue formation inside the scaffold. The objective of this study was to optimize scaffold morphology to prevent this from happening and to determine the optimal scaffold geometric values for connective tissue engineering. After comparing lyophilized crosslinked collagen, compression molded/salt leached PEGT/PBT copolymer and collagen-PEGT/PBT hybrid scaffolds, the PEGT/PBT scaffold was selected for optimization. Geometric parameters were determined using SEM, microcomputed tomography, and flow permeability measurements. Fibroblast were seeded and cultured under dynamic flow conditions for 2 weeks. Cell numbers were determined using CyQuant DNA assay, and tissue distribution was visualized in H&E- and Sirius Red-stained sections. Scaffolds 0.5 and 1.5 mm thick showed bridged connected tissue from top-to-bottom, whereas 4-mm-thick scaffolds only revealed tissue ingrowth until a maximum depth of 0.6-0.8 mm. Rapid prototyped scaffold were used to assess the maximal void space (pore size) that still could be filled with tissue. Tissue bridging between fibers was only found at fiber distances < or =401 +/- 60 microm, whereas filling of void spaces in 3D-deposited scaffolds only occurred at distances < or =273 +/- 55 microm. PEGT/PBT scaffolds having similar optimal porosities, but different average interconnected pore sizes of 142 +/- 50, 160 +/- 56 to 191 +/- 69 microm showed comparable seeding efficiencies at day 1, but after 2 weeks the total cell numbers were significantly higher in the scaffolds with intermediate and high interconnectivity. However, only scaffolds with an intermediate interconnectivity revealed homogenous tissue formation throughout the scaffold with complete filling of all pores. In conclusion, significant amount of connective tissue was formed within 14 days using a dynamic culture process that filled all void spaces of a PEGT/PBT scaffolds with the following geometric parameters: thickness 1.5-1.6 mm, pore size range 90-360 microm, and average interconnecting pore size of 160 +/- 56 microm.

Biocompatible Materials↗

PubMed2006

Electric near-field enhancing properties of a finite-size metal conical nano-tip.

Finite-difference time-domain (FDTD) technique simulations are performed to study the near-field resonance properties of a silver conical nano-tip with a rounded end. Varying the tip geometry, we have computed the electric field distribution, as well as the electric field enhancement factor in the immediate vicinity of the tip apex. The aim of this study is to find optimal geometric parameters of the conical tip, such as its angle and length, in order to maximize the electric field enhancement factor. The increase of the tip length is shown to result in a redshift of the tip resonance wavelength. In addition, some subsidiary (non-dipole) peaks appear for relatively long tips. The peak enhancement values for the small-angle tips increase with the tip length while those for the large-angle ones decrease with it. At the same time, the dependencies of the field enhancement on the cone angle exhibit non-monotonic behavior. In other words, an optimal angle exists allowing one to maximize the electric near field. Finally, the effect of the supporting dielectric medium on the electric field near the tip apex is discussed. In the approximation used, the effect is shown to leave the main conclusions unchanged.

Journal Article↗

PubMed2003

First-principles calculations as a tool for structure validation in electron crystallography.

The crystal structures of Ti(11)Se(4) [Weirich, Ramlau, Simon, Hovmöller & Zou (1996). Nature (London), 382, 144-146] and Ti(45)Se(16) [Weirich (2001). Acta Cryst. A57, 183-191] determined previously from selected-area electron diffraction (SAED) data have been checked for their correctness by means of total energy calculations within the non-local density functional theory. The reliability of the used method was verified by test calculations carried out for the structurally related compound Ti(8)Se(3), which is well known from single-crystal X-ray diffraction [Weirich, Pöttgen & Simon (1996). Z. Kristallogr. 212, 929-930]. For Ti(8)Se(3), structural models from both experiment and calculation show a perfect match (average agreement 0.01 A). This proves that the geometrical optimized models from first-principles calculation can be used as a reliable alternative when good-quality X-ray results cannot be obtained. Calculations carried out for the two structures determined from electron crystallography yielded average improvement of the atomic coordinates of 0.04 and 0.09 A for Ti(11)Se(4) and Ti(45)Se(16), respectively. The optimized cell parameters of the monoclinic structures (both space group C2/m, No. 12) are a = 25.51, b = 3.43, c = 19.19 A, beta = 117.9 degrees for Ti(11)Se(4) and a = 36.31, b = 3.45, c = 16.59 A, beta = 92.1 degrees for Ti(45)Se(16). These results prove that crystals that are too small for single-crystal X-ray diffraction and are difficult to solve by powder diffraction may nevertheless be amenable to accurate structure determination by electron diffraction structure analysis using data from standard SAED and the assumption of quasi-kinematical scattering. Moreover, this study shows that geometry optimization by first-principles calculations is the perfect tool for validation and improvement of complex structural models, which are suspected to have errors owing to the poor quality of experimental data.

Journal Article↗

PubMed2005

Optimizing the integrated pulsed amperometric multicycle step waveform for the determination of tetracyclines.

A method of modified integrated pulsed amperometric detection with multicycle step waveform (Multi-IPAD) following high-performance liquid chromatography (HPLC) was applied for the determination of tetracyclines (TCs) including dimethyltetracycline (DMTC), oxytetracycline (OTC) and tetracycline (TC). The key advantages of the Multi-IPAD are the abilities to enhance sensitivity and reproducibility and the ability to keep working electrode clean through the use of a high-frequent waveform alteration in integration step and the use of a cleaning potential, which is quite different from conventional three-step potential waveform. The analyses were carried out using the mobile phase of acetonitrile-water mixture solution (10:90, v/v) containing 1% perchloric acid on a C(18) column at a flow rate of 0.21 mL/min. The IPAD waveform parameters were optimized to maximize the signal-to-noise ratio (S/N) and successfully applied for the sensitive detection of TCs. The detection limits (S/N=3, 20 microL injected) were 0.07 mg/L for DMTC, 0.08 mg/L for OTC and 0.05 mg/L for TC. The peak height relative standard deviations (RSDs) of every compound for replicate injection (n=15) determined were below 4.6%.

Chromatography, High Pressure Liquid↗

PubMed1989

Highly efficient DNA delivery mediated by pH-sensitive immunoliposomes.

We have previously shown that pH-sensitive immunoliposomes can mediate a target-specific delivery of plasmid DNA to tumor cells grown in a mouse model [Wang, C.-Y., & Huang, L. (1987) Proc. Natl. Acad. Sci. U.S.A. 84, 7851-7855]. The efficiency of delivery in terms of the target cell transformation frequency has now been characterized for both short- and long-term gene expression in a tissue culture system. Herpes simplex virus thymidine kinase (TK) gene was used as a reporter gene. It was placed under the control of the promoter for the rat phosphoenolpyruvate carboxykinase gene, which contains a cAMP regulatory element. Therefore, the expression of the exogenous gene in the target cell, mouse Ltk- cells, can be regulated by cAMP drugs. The plasmid DNA was encapsulated in liposomes using a detergent dialysis method. The efficiency of gene delivery was optimized with respect to the time course and dose of liposome-associated DNA. The existence of antibody of the liposomes was essential for the maximal level of DNA delivery. Delivery was also dependent on the lipid composition of the liposome. The pH-sensitive lipid composition gave 8-fold higher efficiency than the corresponding pH-insensitive composition. The transformation efficiency of the target cell also depended on the regulation of gene expression; cells incubated with dibutyryl-cAMP and theophylline showed a much higher level of transformation frequency than cells incubated without the drugs. When all liposome and incubation parameters are optimized, the Ltk- cells showed a 47% efficiency for the short-term transformation, and 2% for the long-term transformation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed2001

Ergonomic principles of task alignment, visual display, and direction of execution of laparoscopic bowel suturing.

BACKGROUND: Laparoscopic suturing is technically a demanding skill in laparoscopic surgery. Ergonomic experimental studies provide objective information on the important factors and variables that govern optimal endoscopic suturing. Our objective was to determine the optimum physical alignment, visual display, and direction of intracorporeal laparoscopic bowel suturing using infrared motion analysis and telemetric electromyography (EMG) systems. METHODS: Ten surgeons participated in the study; each sutured 50-mm porcine small bowel enterotomies toward and away from the surgeon in the vertical and horizontal bowel plane with either isoplanar (image display corresponds with actual lie of the bowel) or nonisoplanar (bowel displayed horizontally but mounted vertically in the trainer and vice versa) display. The end points were the placement error score, execution time, leakage pressure, motion analysis, and telemetric EMG parameters of the surgeon's dominant upper limb. RESULTS: Suturing was demonstrably easier in the vertical than in the horizontal plane, resulting in a better task quality (placement error score, p < 0.0001; leakage pressure, p < 0.005) and shorter execution time (p < 0.05). Nonisoplanar display of the surgical anatomy degrades performance in terms of both task efficiency and task quality. On motion analysis, a wider angle of excursion and lower angular velocity were observed during the vertical suturing with isoplaner display. Compared to horizontal suturing, supination at the wrist was significantly greater during vertical than horizontal suturing (p < 0.05). Within each category (vertical vs horizontal suturing), the direction of suturing (toward/away from the surgeon) did not influence the extent of pronation/ supination at the wrist. In line with the degraded performance, significantly more muscle work was expended during horizontal suturing. This affected the forearm flexors (p < 0.05), arm flexors and extensors (p < 0.005 and p < 0.05, respectively), and deltoid muscles (p < 0.005) and was accompanied by significantly more fatigue in the related muscles. Small bowel enterotomies sutured toward the surgeon in both the vertical and the horizontal planes exhibited less placement error score than when sutured away from the surgeon, with no significant difference in the motion analysis and EMG parameters. CONCLUSIONS: Optimal laparoscopic suturing (better task quality and reduced execution time) is achieved with vertical suturing toward the surgeon with isoplanar monitor display of the operative field. The poorer task performance observed during horizontal suturing is accompanied by more muscle work and fatigue, and it is not improved by monitor display of the enterotomy in the vertical plane.

Animals↗

PubMed1995

Long-term effect of sphincteric fatigue during bladder neurostimulation.

Commercially available stimulators lack several features, including multiple channel capability and flexible stimulation parameters. These factors limit clinical application. A new computerized electrical stimulator system was developed by our team and evaluated for its efficacy in bladder evacuation in an animal model after spinal cord transection. The system can generate a wide range of stimulation characteristics and has the feature of being a programmable multichannel pacemaker. It has enabled us to induce a reversible fatigue to the external sphincter that results in proper bladder emptying on stimulation. Using this new bladder pacemaker, 8 dogs were studied. We applied the concept of fatiguing of the external sphincter via the pudendal nerve to avoid rhizotomy. We determined the optimal stimulation parameters that can reliably empty the dog's bladder for the duration of the experiment, which lasted for 8 months. The new computerized electrical stimulation system achieved the objective of reducing bladder outlet resistance without the need for sacral rhizotomy.

Animals↗

PubMed2004

Calculus fragmentation in laser lithotripsy.

The intracorporeal treatment of urinary calculi with lasers is presented, which describes laser-calculus interactions associated with lithotripsy. Reliable fragmentation of calculi with diverse compositions and minimal collateral tissue damage are primarily contingent upon laser parameters (wavelength, pulse duration, and pulse energy) and physical properties of calculi (optical, mechanical, and chemical). The pulse duration governs the dominant mechanism in calculi fragmentation, which is either photothermal or photoacoustical/photomechanical. Lasers with long pulse durations (i.e. > tens of micros) induce a temperature rise in the laser-affected zone with minimal acoustic waves; material is removed by means of vaporization, melting, mechanical stress, and/or chemical decomposition. Short-pulsed laser ablation (i.e. < 10 micros), on the other hand, produces shock waves, and the resultant mechanical energy fragments calculi. Work continues throughout the world to evaluate the feasibility of advanced lasers in lithotripsy and to optimize laser parameters and light delivery systems pertinent to efficient fragmentation of calculi.

Biophysical Phenomena↗

PubMed1995

Hemorrheological changes associated with brain death and their implications for potential organ donors.

Successful transplantation of donor organs from brain-dead patients requires adequate maintenance of hemodynamic parameters. Blood flow and tissue perfusion are highly dependent upon hemorrheology. The aim of the present study was to evaluate hemorrheological parameters in potential organ donors compared to healthy volunteers. Whole blood-, plasma- and corrected blood viscosity, hematocrit, erythrocyte deformability, and erythrocyte aggregation were obtained in ten consecutive brain-dead patients and ten matched volunteers. Compared to controls, hematocrit and whole blood viscosity at high and medium shear rates and erythrocyte deformability were significantly decreased. Plasma viscosity was significantly increased in all patients. In the same group, a highly significant increase was observed at all shear rates when viscosity was corrected for hematocrit. Definite rheological abnormalities were found in the blood of brain-dead patients, something which might lead to impaired organ function after transplantation. Therefore, optimizing such parameters by special fluid management may be of importance in potential organ donors.

Adolescent↗

PubMed2002

Methanocalculus taiwanensis sp. nov., isolated from an estuarine environment.

Two novel hydrogenotrophic methanogens, designated strains P2F9704aT and P2F9705, were isolated from an estuary in Eriln Shi, Taiwan. The cells of strain P2F9704aT were non-motile, irregular cocci 0.9-1.4 microm in diameter. They stained gram-negative. The cells catabolized formate and H2+CO2 to produce methane, but did not utilize acetate, methanol, trimethylamine, ethanol or secondary alcohols as methanogenic substrates. The optimal growth parameters for strain P2F9704aT were pH 6.7, 37 degrees C and 0.5% NaCl. Acetate was required for cell growth even though it was not a substrate for methanogenesis. The trace element tungsten was not required but slightly stimulated the growth of strain P2F9704aT. However, tungsten extended the growth ranges relating to temperature, pH and salt. The sequences of the 16S rRNA genes of strains P2F9704aT and P2F9705 were nearly identical and possessed 99.1 and 98.5% similarity to the genes of Methanocalculus pumilus and Methanocalculus halotolerans, respectively. In addition, strain P2F9704aT possessed 14 and 12% DNA relatedness with respect to Methanocalculus pumilus and Methanocalculus halotolerans, respectively. In addition, the optimal salt concentrations, the cellular protein profiles and the molecular masses of surface-layer protein subunits of strain P2F9704aT were different from those of the other two known Methanocalculus species. On the basis of these observations, it is proposed that these two organisms should be placed in a new species, namely Methanocalculus taiwanensis. The type strain is P2F9704aT (= OCM 671T = CCRC 16182T = DSM 14663T).

Archaeal Proteins↗

PubMed1993

Accelerometer-based adaptive-rate pacing: a multicenter study. European EXCEL Study Group.

UNLABELLED: A new adaptive rate pacemaker, using an accelerometer to detect body motion as an indicator of metabolic demand, was evaluated in 13 centers located in five countries. During the study, 55 patients with a broad range of indications were implanted with the EXCEL VR single chamber pacemaker. One month evaluations were completed on a subgroup of 37 patients. The pacemaker response was optimized before discharge using a simple walking test. An "exercise test" recording feature in the programmer eliminated the need for ECG monitoring. At nominal settings, the mean (+/- SD) pacing rate increased 29 +/- 9 ppm while walking slowly and 44 +/- 11 ppm (n = 33) during a brisk walk. This information was used to optimize the parameter settings. Without further changes to the programmed settings the patients were subsequently tested 2-4 weeks postimplant with a symptom-limited treadmill test using the chronotropic assessment exercise protocol (CAEP). Mean pacing rate increased from 74.5 +/- 2.5 ppm (n = 24) at rest to 118.6 +/- 12.2 ppm (n = 21) at 3 mph/6% grade to 143.5 +/- 3.5 ppm (n = 2) at 3.8 mph/8% grade. CONCLUSION: The individual responses were proportional to the physical exertion imposed on the patients. Pacing rates were considered to be appropriate using the chronotropic response zone as a criterion for appropriate rate modulation. A simple walking test utilizing the exercise test facility, results in appropriate optimization of the pulse generator to the individual patient.

Acceleration↗

PubMed1987

Antagonist muscle activity during human forearm movements under varying kinematic and loading conditions.

During the performance of unidirectional, single-joint movements it is known that muscle activation is not confined to the agonist, but is generally seen in the antagonist as well, appearing as a burst of antagonist activity if the movement is quite rapid. We have studied the integral over time of antagonist electromyographic activity (Eant) during forearm movements encompassing a wide range of movement speeds, amplitudes and inertial loads, with two intents: first, to provide an empirical description of the dependence of Eant on kinematic and loading parameters which would be valid over a several hundred-fold range of Eant; and second, to test the hypothesis that Eant is related to the torque necessary for braking the movement. With respect to the first aim, we found that for all subjects Eant was correlated with a simple algebraic expression dependent upon peak velocity, movement amplitude and total moment of inertia, when each of these movement parameters was varied either singly or in combination. Although a more complex algebraic expression, in which exponents for each parameter were optimized for a given subject, provided marginally better correlations with Eant, we prefer the simpler expression on the grounds that it provides similar correlations without requiring a different form for each subject. With respect to the second aim of the study, the braking hypothesis was supported by the fact that the simple expression could be interpreted as representing the average net torque required for braking. However, in experiments in which an external torque was provided to assist in braking, antagonist muscle activity was not reduced as much as would be expected if provision of braking torque was the sole function of antagonist activity. We conclude that: (1) antagonist activity varies with kinematic parameters and inertial load in accordance with the requirements for braking the limb, but (2) the activity may in fact provide a multiple of the torque that is required for braking alone, with excess activity presumably offset by concurrent agonist activity. Possible roles of such cocontraction are discussed.

Adolescent↗

PubMed2002

Mechanism and prediction for contamination of freshwater bivalves (Unionidae) with the cyanobacterial toxin microcystin in hypereutrophic Lake Suwa, Japan.

Seasonal changes of microcystin (MC) bioaccumulation in three freshwater Unionid bivalves, Anodonta woodiana, Cristaria plicata, and Unio douglasiae, were investigated in the hypereutrophic Lake Suwa. Total MC concentrations (MC-RR and -LR) as determined by reverse-phase high-performance liquid chromatography were at high levels in the hepatopancreas of C. plicata and U. douglasiae, with maxima at 297 and 420 microg/g dry weight, respectively. The amounts and seasonal changes in the accumulated MC concentration differed in all species. The total MC concentration of A. woodiana was always less than that of other species (maximum concentration of 12.6 microg/g dry weight). The toxin concentration of C. plicata remained very low in summer, when the Microcystis bloom occurred, but increased rapidly in autumn, when the toxic bloom disappeared. For U. douglasiae, simple regression analyses were performed to clarify the relationship between MC bioaccumulation and environmental parameters such as water temperature, chlorophyll a, suspended solids (SS), intracellular MC per unit volume of lake water and per-unit weight of SS and extracellular MC. The toxin concentration of U. douglasiae correlated more closely with qualitative factors, with intracellular toxin per SS (p < 0.001, R(2) = 0.72) than with quantitative factors such as chlorophyll a and intracellular toxin per unit volume of lake water. No correlation could be found between MC in the tissues and extracellular MC. These results indicate that a long-term survey is needed to assess the safety of bivalves. The study should take into consideration both interspecific differences in toxin content and what is the optimal monitoring parameter.

Animals↗

PubMed2003

Metallic artefacts in MR imaging: effects of main field orientation and strength.

AIM: To determine the effect of metallic implant positioning on magnetic resonance (MR) imaging artefacts, and to determine the optimal imaging parameters for minimization of metallic artefacts. MATERIALS AND METHODS: In a phantom and in three joints with non-ferromagnetic metallic implants imaged at 1.5 and/or at 0.2 T, we examined the influence of the static magnetic field (B(0)) strength and orientation, frequency-encoding direction, and type of imaging sequence on metallic artefacts. RESULTS: The impact of artefacts caused by metallic objects depends mainly on the relationship between the anatomy of interest and the orientation of the object relative to the direction of B(0). The main field strength plays a less important role, but its orientation depends on the type of MR imager. CONCLUSION: MR artefacts can be easily minimized by optimally positioning patients with metallic implants in the magnet. Knowledge of how this influences MR imaging is helpful in patient selection and guiding limb positioning.

Artifacts↗

PubMedDate not supplied

The role of physical agents in modulating pain.

This article presents a review of the literature on the use of physical agents in modulating pain associated the hand and upper extremity musculoskeletal conditions. The physical agents presented include superficial heating agents, cryotherapy, ultrasound, and transcutaneous electrical nerve stimulation. There has been increased interest in modes of transdermal drug delivery, including iontophoresis, phonophoresis, and the application of transdermal patches. Treatment applications, parameters, and integration strategies are suggested. The purposes of this article are to review which physical agents are used to treat pain or inflammation and to discuss their relevant application to hand therapy practice. Today's health care climate requires therapists to select treatment strategies that are efficient, safe, and clinically effective. Although physical agents are widely used to manage pain in hand therapy, there is little scientific evidence to support their efficacy. Most information regarding the rationale for the use of physical agents in pain management is based on tradition, data extrapolated from basic science research, and uncontrolled randomized clinical trials. This paper discusses the need for additional research to establish clinical efficacy and determine optimal treatment parameters for the physical agents used most often to modulate pain in hand therapy.

Acute Disease↗