Successful Use of Platelet-Rich Plasma for Chronic Plantar Fasciitis

Background:

There are limited data on the use of platelet-rich plasma (PRP) for treating chronic plantar fasciitis.

Questions/Purposes:

The purpose of this study was to document the clinical outcomes of patients who were treated with PRP injections for plantar fasciitis to determine the degree to which injections were able to decrease the visual analogue scale (VAS) pain scores and improve patient reported functional scores.

Methods:

This was a retrospective review of 23 consecutive patients treated with PRP for chronic plantar fasciitis (symptoms lasting over 6 months). Patients returned after 4 weeks for a postinjection follow-up. A second injection was given if significant improvement was not obtained by that time. Postinjection foot and ankle outcome scores (FAOS), 12-item short form health survey (SF-12), and VAS scores were collected at a minimum of 6 months follow-up.

Results:

Thirty injections were given in 23 patients, with one patient lost to follow-up. The mean VAS score improved from 7 to 4. The pain, symptoms, and quality of life subscales of the FAOS and SF-12 significantly improved from preinjection scores. Five patients went on to have endoscopic release of the plantar fascia at an average of 94 days after the last injection (range, 22–314 days). Six patients obtained full resolution of symptoms while the majority of patients were able to forgo surgery due to improvement from the PRP injection.

Conclusion:

These results provide preliminary information on the safety and efficiency of PRP injection as treatment for chronic plantar fasciitis.

Electronic supplementary material

The online version of this article (doi:10.1007/s11420-012-9321-9) contains supplementary material, which is available to authorized users.     

Methods for voltage-sensitive dye imaging of rat cortical activity with high signal-to-noise ratio

We describe methods to achieve high sensitivity in voltage-sensitive dye (VSD) imaging from rat barrel and visual cortices in vivo with the use of a blue dye RH1691 and a high dynamic range imaging device (photodiode array). With an improved staining protocol and an off-line procedure to remove pulsation artifact, the sensitivity of VSD recording is comparable with that of local field potential recording from the same location. With this sensitivity, one can record from approximately 500 individual detectors, each covering an area of cortical tissue 160 microm in diameter (total imaging field approximately 4 mm in diameter) and a temporal resolution of 1,600 frames/s, without multiple-trial averaging. We can record 80-100 trials of intermittent 10-s trials from each imaging field before the VSD signal reduces to one half of its initial amplitude because of bleaching and wash-out. Taken together, the methods described in this report provide a useful tool for visualizing evoked and spontaneous waves from rodent cortex.     

Alcohol withdrawal is associated with a downregulation of large-conductance Ca2+-activated K+ channels in rat inferior colliculus neurons

Rationale

Large conductance calcium-activated potassium (BK_Ca or K_Ca1.1) channels are well-known molecular targets for the action of alcohol and therefore may play an important role in the pathogenesis of alcohol withdrawal syndrome.

Objectives

We evaluate the modifications of total outward K⁺ currents and protein expression of BK_Ca channels α-subunit in inferior colliculus (IC) neurons obtained from controls and rats subjected to alcohol withdrawal associated with enhanced susceptibility to seizures.

Methods

Outward K⁺ currents and BK_Ca channel proteins were measured using the whole cell configuration of patch clamp techniques and Western blot analysis, respectively.

Results

Total outward K⁺ current density was significantly reduced in IC neurons at 24 and 48 h during the alcohol withdrawal period when the susceptibility to seizures was maximal and absent, respectively. The iberiotoxin-sensitive (BK_Ca) current density and conductance also were significantly reduced at 24 h following alcohol withdrawal. Consistent with functional data, the levels of protein expression of α-subunit associated with BK_Ca channels also was significantly reduced in IC neurons at 24 and 48 h following alcohol withdrawal.

Conclusions

The downregulation of BK_Ca channels outlasts the finite period of elevated susceptibility to alcohol withdrawal seizures. These findings indicate that BK_Ca channels, per se, may not be fundamentally important for the generation of alcohol withdrawal seizures.     

Effect of hybrid circle reservoir injected with wavelet-neurons on performance of echo state network

The Echo State Network (ESN) has attracted wide attention for its superior performance in chaos time-series prediction. However, the complicated ESN topologies and the random reservoirs are difficult to implement in practice. We propose a hybrid circle reservoir (HCR) ESN architecture that comprises the following features: (1) built with low complexity circle reservoir; (2) partly injected with wavelet-neurons; (3) uses fixed connection weights in both input matrix and dynamic reservoir matrix. The HCR model has been successfully applied to solve six application problems, and the results are used to compare with the existing low complexity simple circle reservoir (SCR) ESN. Furthermore, we analyze the performance of the new model under different ratios of wavelet-neurons, different circle distributions and different input sign patterns. Simulation results show that the HCR model achieves significantly better performance in prediction accuracy than the SCR model. Additionally, the HCR model has similar low complexity as the SCR. Moreover, the short-term memory capacity (MC) in the HCR is close to the theoretical optimal MC value.     

A new switching design to finite-time stabilization of nonlinear systems with applications to neural networks

This paper is concerned with the optimal finite-time stabilization problem for nonlinear systems. For the given stabilization strength, a new switching protocol is designed to stabilize the system with a fast speed. The obtained protocol covers both continuous control and discontinuous one under the framework of Filippov solutions. Some criteria are discussed in detail on how to choose an optimal protocol such that the finite stabilization time can be shortened. Finally, the main theory results are applied to the general neural networks by one numerical example to illustrate the effectiveness of the proposed design method.     

Alexia due to ischemic stroke of the visual word form area

The visual word form area (VWFA) is a region in the posterior left occipitotemporal cortex adjacent to the fusiform gyrus hypothesized to mediate word recognition. Evidence supporting the role of this area in reading comes from neuroimaging studies of normal subjects, case-controlled lesion studies, and studies of patients with surgical resection of the VWFA for tumors or epilepsy. Based on these prior reports, a small discrete lesion to the VWFA would be expected to cause alexia in a literate person without prior brain process, but such a case has not previously been reported to our knowledge. Here, we report the case of a previously-healthy 63-year-old man with the acute onset of alexia without other significant impairments. Magnetic resonance imaging (MRI) of the brain revealed a small ischemic stroke localized to the inferior left occipitotemporal cortex, corresponding to the approximate location of the putative VWFA. Characteristic of pure alexia, testing in the weeks following the stroke revealed a letter-by-letter reading strategy and a word length effect on single word reading. Formal visual field testing was normal. There was no color anomia, or object or face recognition deficits, although a mild agraphia may have been present. This case of acute-onset alexia in a previously normal individual due to a small stroke restricted to the VWFA and sparing occipital cortex and white matter pathways supports the conclusion that the VWFA is crucial for reading.     

Allelic variation of killer cell immunoglobulin-like receptor 2DS5 impacts glycosylation altering cell surface expression levels

Natural killer cell stimulatory receptor gene, KIR2DS5, is polymorphic. While KIR2DS5^∗002 is most frequently observed, other alleles have also been found. The proteins encoded by these alleles (KIR2DS5^∗002–^∗009) are expressed at varying levels on the surface of NKL and Jurkat transfectants. Gel electrophoresis of all allelic products showed two isoforms which differ in the extent of maturation of N-linked glycosylation. These isoforms differed in intensity and molecular weight among the allelic products. Site-directed mutagenesis was used to identify polymorphic variation at residues 123 and 157 as key in altering glycosylation and levels of surface expression.     

Improving the performance of poly(3,4-ethylenedioxythiophene) for brain–machine interface applications

Conducting polymers, especially poly(3,4-ethylenedioxythiophene) (PEDOT) based materials, are important for developing highly sensitive and microscale neural probes. In the present work, we show that the conductivity and stability of PEDOT can be significantly increased by switching the widely used counter anion poly(styrenesulfonate) (PSS) to the smaller tetrafluoroborate (TFB) anion during the electrodeposition of the polymer. Time-dependent impedance measurements of polymer modified implantable microwires were conducted in physiological buffer solutions under accelerated aging conditions and the relative stability of PEDOT:PSS and PEDOT:TFB modified microwires was compared over time. This study was also extended to carbon nanotube (CNT) incorporated PEDOT:PSS which, according to some reports, is claimed to enhance the stability and electrical performance of the polymer. However, no noticeable difference was observed between PEDOT:PSS and CNT:PEDOT:PSS in our measurements. At the biologically relevant frequency of 1 kHz, PEDOT:TFB modified microwires exhibit approximately one order of magnitude higher conductivity and demonstrate enhanced stability over both PEDOT:PSS and CNT:PEDOT:PSS modified microwires. In addition, PEDOT:TFB is not neurotoxic and we show the proof-of-concept for both in vitro and in vivo neuronal recordings using PEDOT:TFB modified microelectrode arrays and chronic electrodes, respectively. Our findings suggest that PEDOT:TFB is a promising conductive polymer coating for the recording of neural activities.