Factor Structure, Validity, and Reliability of the STarT Back Screening Tool in Italian Obese and Non-obese Patients With Low Back Pain.

Background: The STarT Back Screening Tool (SBST) is a self-report questionnaire developed for prognostic purposes which evaluates risk factors for disability outcomes in patients with chronic low back pain. Previous studies found that its use enables to provide a cost-effective stratified care. However, its dimensionality has been assessed only using exploratory approaches, and reports on its psychometric properties are conflicting. Objective: The objective of this study was to assess the factorial structure and the psychometric properties of the Italian version of the STarT Back Screening Tool (SBST). Materials and Methods: Patients with medical diagnosis of low back pain were enrolled from a rehabilitation unit of a tertiary care hospital specialized in obesity care (Sample 1) and from a clinical internship center of an osteopathic training institute (Sample 2). At baseline and after 7 days patients were asked to fill a battery of self-report questionnaires. The factorial structure, internal consistency, test-retest reliability, and construct validity of the SBST were assessed. Results: One hundred forty-six patients were enrolled (62 from Sample 1 and 84 from Sample 2). The confirmatory factor analysis showed that the fit of the original two-correlated factors model was adequate (CFI = 0.98, TLI = 0.99, RMSEA = 0.03). Cronbach's α of the total scale (α = 0.64) and of the subscales (physical subscale α = 0.55; psychological subscale α = 0.61) was below the cutoffs, partly because of the low correlation of item 2 with the other items. Test-retest reliability was adequate (ICC = 0.84). The SBST had moderate correlations with comparisons questionnaires, except for the Roland-Morris Disability Questionnaire, which had a high correlation (r = 0.65). Discussion: The SBST has adequate psychometric properties and can be used to assess prognostic factors for disability in low back pain patients.

Sham treatment effects in manual therapy trials on back pain patients: a systematic review and pairwise meta-analysis.

OBJECTIVE: To assess the effects and reliability of sham procedures in manual therapy (MT) trials in the treatment of back pain (BP) in order to provide methodological guidance for clinical trial development. DESIGN: Systematic review and meta-analysis. METHODS AND ANALYSIS: Different databases were screened up to 20 August 2020. Randomised controlled trials involving adults affected by BP (cervical and lumbar), acute or chronic, were included.Hand contact sham treatment (ST) was compared with different MT (physiotherapy, chiropractic, osteopathy, massage, kinesiology and reflexology) and to no treatment. Primary outcomes were BP improvement, success of blinding and adverse effect (AE). Secondary outcomes were number of drop-outs. Dichotomous outcomes were analysed using risk ratio (RR), continuous using mean difference (MD), 95% CIs. The minimal clinically important difference was 30 mm changes in pain score. RESULTS: 24 trials were included involving 2019 participants. Very low evidence quality suggests clinically insignificant pain improvement in favour of MT compared with ST (MD 3.86, 95% CI 3.29 to 4.43) and no differences between ST and no treatment (MD -5.84, 95% CI -20.46 to 8.78).ST reliability shows a high percentage of correct detection by participants (ranged from 46.7% to 83.5%), spinal manipulation being the most recognised technique.Low quality of evidence suggests that AE and drop-out rates were similar between ST and MT (RR AE=0.84, 95% CI 0.55 to 1.28, RR drop-outs=0.98, 95% CI 0.77 to 1.25). A similar drop-out rate was reported for no treatment (RR=0.82, 95% 0.43 to 1.55). CONCLUSIONS: MT does not seem to have clinically relevant effect compared with ST. Similar effects were found with no treatment. The heterogeneousness of sham MT studies and the very low quality of evidence render uncertain these review findings.Future trials should develop reliable kinds of ST, similar to active treatment, to ensure participant blinding and to guarantee a proper sample size for the reliable detection of clinically meaningful treatment effects. PROSPERO REGISTRATION NUMBER: CRD42020198301.

A Pilot Study of Jugular Compression (Queckenstedt maneuver) for Cranial Movement Perception.

CONTEXT: Osteopathy in the cranial field (OCF) is among the most controversial topics of osteopathic practice. The mechanism by which cranial movement (CM) occurs is poorly understood, but includes speculation that intracranial pressure can generate a movement of the cranial bones. If this model is valid, an increase in intracranial pressure produced by bilateral compression of internal jugular veins, or the Queckenstedt maneuver (Q-test), should be detectable. OBJECTIVE: To determine whether osteopaths can perceive a palpable change in CM when the Q-test is applied. METHODS: Blindfolded osteopaths experienced in OCF evaluated the CM of volunteers as a trained clinician applied the Q-test. The osteopaths reported any change in CM amplitude during 3 different 1-minute periods. The total number of variations perceived in each period (PV) by all osteopaths on all volunteers was analyzed. The Kruskal Wallis test was used to evaluate the differences between the test periods. The Mann-Whitney test was used for a pairwise comparison. Statistical significance was set at P≤.05. RESULTS: Eight osteopaths participated in this study and evaluated the CM of 6 volunteers. A Kruskal-Wallis test of the PV between monitoring periods revealed a statistically significant difference (P<.001). A Mann-Whitney Test showed there was a significant increase in PV between the compression period and the 2 other monitoring periods (base P=.003 and expectation P=.009). CONCLUSION: Osteopaths could detect a change in the amplitude of CM after the Q-test was applied. Although this was a small-scale pilot study, our data represent a starting point for understanding whether an intracranial or an extracranial mechanism is responsible for the CM.

How type and number of training sessions influence the reliability of palpation.

INTRODUCTION: Accurate and reliable palpation is needed to identify anatomical landmarks as well as to assess motion and dysfunctions. Although different trials suggested that training might increase reliability of palpation, the poor dependability of the examined tests may show the need to review the teaching methods to improve palpatory accuracy? The aims of this study were: METHODS: 82 examiners with different years of experience were enrolled from AIMO institute. Two different type of training sessions were performed (individual and group training). A total of 5 training sessions were performed during 5 weeks and 5 different models with a similar BMI were used. A uni-variated statistical analysis was used to evaluate the main effect of type and number of trainings, a multi-variated analysis was used to verify cross-effects. RESULTS: Overall results show moderate reliability for the correct detection of the position of the heel lift (Random probability being 33%, GT = 58.6% and SIPS = 57.1%, both P-value < 0.001). No difference was shown between the types of training (p-value GT = 0.503, p-value PSIS = 1) and no overall improvement was shown after the first training (P-value(GT) = 0.25, P-value(PSIS) = 0.96). The professional group improved the reliability during the training sessions starting from substantial reliability and ended with an almost perfect reliability (P-value GT = 0.0029, P-Value PSIS<0.001). Whereas the 3rd 4th and 5th showed a decreased performance. CONCLUSIONS: Type of training sessions seems not to influence reliability of palpation accuracy. The improvement of reliability during the training sessions seems to be related to the experience of examiners, which plays an important role in reliability and the learning experience.

Fast and slow gating are inherent properties of the pore module of the K+ channel Kcv.

Kcv from the chlorella virus PBCV-1 is a viral protein that forms a tetrameric, functional K+ channel in heterologous systems. Kcv can serve as a model system to study and manipulate basic properties of the K+ channel pore because its minimalistic structure (94 amino acids) produces basic features of ion channels, such as selectivity, gating, and sensitivity to blockers. We present a characterization of Kcv properties at the single-channel level. In symmetric 100 mM K+, single-channel conductance is 114+/-11 pS. Two different voltage-dependent mechanisms are responsible for the gating of Kcv. "Fast" gating, analyzed by beta distributions, is responsible for the negative slope conductance in the single-channel current-voltage curve at extreme potentials, like in MaxiK potassium channels, and can be explained by depletion-aggravated instability of the filter region. The presence of a "slow" gating is revealed by the very low (in the order of 1-4%) mean open probability that is voltage dependent and underlies the time-dependent component of the macroscopic current.

Chlorella virus ATCV-1 encodes a functional potassium channel of 82 amino acids.

Chlorella virus PBCV-1 (Paramecium bursaria chlorella virus-1) encodes the smallest protein (94 amino acids, named Kcv) previously known to form a functional K+ channel in heterologous systems. In this paper, we characterize another chlorella virus encoded K+ channel protein (82 amino acids, named ATCV-1 Kcv) that forms a functional channel in Xenopus oocytes and rescues Saccharomyces cerevisiae mutants that lack endogenous K+ uptake systems. Compared with the larger PBCV-1 Kcv, ATCV-1 Kcv lacks a cytoplasmic N-terminus and has a reduced number of charged amino acids in its turret domain. Despite these deficiencies, ATCV-1 Kcv accomplishes all the major features of K+ channels: it assembles into a tetramer, is K+ selective and is inhibited by the canonical K+ channel blockers, barium and caesium. Single channel analyses reveal a stochastic gating behaviour and a voltage-dependent conductance that resembles the macroscopic I/V relationship. One difference between PBCV-1 and ATCV-1 Kcv is that the latter is more permeable to K+ than Rb+. This difference is partially explained by the presence of a tyrosine residue in the selective filter of ATCV-1 Kcv, whereas PBCV-1 Kcv has a phenylalanine. Hence, ATCV-1 Kcv is the smallest protein to form a K+ channel and it will serve as a model for studying structure-function correlations inside the potassium channel pore.

The potassium channel KAT1 is activated by plant and animal 14-3-3 proteins.

14-3-3 proteins modulate the plant inward rectifier K+ channel KAT1 heterologously expressed in Xenopus oocytes. Injection of recombinant plant 14-3-3 proteins into oocytes shifted the activation curve of KAT1 by +11 mV and increased the tau(on). KAT1 was also modulated by 14-3-3 proteins of Xenopus oocytes. Titration of the endogenous 14-3-3 proteins by injection of the peptide Raf 621p resulted in a strong decrease in KAT1 current (approximately 70% at -150 mV). The mutation K56E performed on plant protein 14-3-3 in a highly conserved recognition site prevented channel activation. Because the maximal conductance of KAT1 was unaffected by 14-3-3, we can exclude that they act by increasing the number of channels, thus ruling out any effect of these proteins on channel trafficking and/or insertion into the oocyte membrane. 14-3-3 proteins also increased KAT1 current in inside-out patches, suggesting a direct interaction with the channel. Direct interaction was confirmed by overlay experiments with radioactive 14-3-3 on oocyte membranes expressing KAT1.

Electrokinetics of miniature K+ channel: open-state V sensitivity and inhibition by K+ driving force.

Kcv, isolated from a Chlorella virus, is the smallest known K+ channel. When Kcv is expressed in Xenopus oocytes and exposed to 50 mM: [K+](o), its open-state current-voltage relationship (I-V) has the shape of a "tilted S" between -200 and +120 mV. Details of this shape depend on the conditioning voltage (V (c)) immediately before an I-V recording. Unexpectedly, the I-V relationships, recorded in different [K+](o), do intersect. These characteristics are numerically described here by fits of a kinetic model to the experimental data. In this model, the V (c) sensitivity of I-V is mainly assigned to an affinity increase of external K+ association at more positive voltages. The general, tilted-S shape as well as the unexpected intersections of the I-V relationships are kinetically described by a decrease of the cord conductance by the electrochemical driving force for K+ in either direction, like in fast V-dependent blocking by competing ions.

Novel Semliki Forest virus vectors with reduced cytotoxicity and temperature sensitivity for long-term enhancement of transgene expression.

Alphaviral vectors inhibit host cell protein synthesis and are cytotoxic. To overcome these limitations, we modified the nonstructural protein-2 (nsP2) gene in the Semliki Forest virus (SFV) vector, pSFV1. Packaging of SFV replicons with two point mutations in nsP2 resulted in high-titer recombinant SFV(PD) particles. SFV(PD) led to more efficient host cell protein synthesis, exhibited reduced cytotoxicity and improved cell survival, and allowed greater and prolonged transgene expression than the original vector, SFV. In dissociated hippocampal neurons and organotypic rat hippocampal slices, SFV(PD) infection preserved neuronal morphology and synaptic function more efficiently than SFV. Combination of the two point mutations with a replication-persistent mutation in nsP2 resulted in a highly temperature-sensitive vector, SFV(PD713P), which efficiently transduced neurons in hippocampal slice cultures. At 31 degrees C, SFV(PD713P) allowed continuous transgene expression in BHK cells, at amounts comparable to SFV(PD). These new SFV mutants are expected to substantially broaden the application of alphaviral vectors in neurons and other mammalian cells.

Multimodal quantal release at individual hippocampal synapses: evidence for no lateral inhibition.

Most CNS synapses investigated thus far contain a large number of vesicles docked at the active zone, possibly forming individual release sites. At the present time, it is unclear whether these vesicles can be discharged independently of one another. To investigate this problem, we recorded miniature excitatory currents by whole-cell and single-synapse recordings from CA3-CA1 hippocampal neurons and analyzed their stochastic properties. In addition, spontaneous release was investigated by ultrastructural analysis of quickly frozen synapses, revealing vesicle intermediates in docking and spontaneous fusion states. In these experiments, no signs of inhibitory interactions between quanta could be detected up to 1 msec from the previous discharge. This suggests that exocytosis at one site does not per se inhibit vesicular fusion at neighboring sites. At longer intervals, the output of quanta diverged from a random memoryless Poisson process because of the presence of a bursting component. The latter, which could not be accounted for by random coincidences, was independent of Ca2+ elevations in the cytosol, whether from Ca2+ flux through the plasma membrane or release from internal stores. Results of these experiments, together with the observation of spontaneous pairs of omega profiles at the active zone, suggest that multimodal release is produced by an enduring activation of an integrated cluster of release sites.