sEMG activity of masticatory, neck, and trunk muscles during the treatment of scoliosis with functional braces. A longitudinal controlled study

Background

Studies on the relationship between occlusal problems and the spine are of increasing interest. In this study, we monitored the sEMG activity of masticatory, neck, and trunk muscles during the treatment of scoliosis in young patients, and compared the data with a control of untreated group.

Subjects and methods

Twelve white Caucasian patients (nine males and three females; mean age of 8.0 ± 1.5 years) with scoliosis and Class I occlusion (without crowding) were included in this study (study group). Fifteen healthy subjects (nine males and six females; mean age of 9.5 ± 0.8 years) were recruited as control group. The subjects were visited before they underwent the treatment of scoliosis, as well as after 3 (T1) and 6 months (T2) of their treatment for scoliosis. The patients were instructed to wear the device during sleep and during the day, according to the protocol given by their orthopedic.

Results

The treated group showed statistically significant changes in the sEMG activity of masticatory, neck, and trunk muscles, both at rest and during MVC of the mandible with respect to T0. The masseter and the anterior temporalis showed a significant improvement in the asymmetry index from T0 to T2. On the other hand, subjects in the control group did not register much change.

Conclusion

Our findings suggest that the use of a functional device for the treatment of scoliosis induces a significant reduction in the asymmetry index of the trunk muscles, as well as a significant increase in the contractility of masticatory muscles.     

Normalizing surface electromyographic measures of the masticatory muscles: Comparison of two different methods for clinical purpose

PurposeTo compare a new normalization technique (wax pad, WAX) with the currently utilized cotton roll (COT) method in surface electromyography (sEMG) of the masticatory muscles.MethodssEMG of the masseter and anterior temporalis muscles of 23 subjects was recorded while performing two repetitions of 5 s maximum voluntary clenches (MVC) on COT and WAX. For each task, the mean value of sEMG amplitude and its coefficient of variation were calculated, and the differences between the two repetitions computed. The standard error of measurement (SEM) was calculated. For each subject and muscle, the COT-to-WAX maximum activity increment was computed. Participant preference between tasks was also recorded.ResultsWAX MVC tasks had larger maximum EMG amplitude than COT MVC tasks (P < 0.001), with COT-to-WAX maximum amplitude increments of 61% (temporalis) and 94% (masseter) (P = 0.006). WAX MVC had better test-retest repeatability than COT. For both MVC modalities, the mean amplitude (P > 0.391) and its coefficient of variation were unchanged (P > 0.180). The WAX task was the more comfortable for 18/23 subjects (P = 0.007).ConclusionWAX normalization ensures the same stability level of maximum EMG amplitude as COT normalization, but it is more repeatable, elicits larger maximum muscular contraction, and is felt to be more comfortable by subjects.     

Bis-(4-methylumbelliferyl) phosphate as a substrate for the surface membrane-associated phosphodiesterase activity of pig platelets

It was found that the newly-available compound, bis-(4-methylumbelliferyl) phosphate, could be used as a substrate for the pig platelet surface membrane-associated phosphodiesterase activity, usually assayed with $\text{bis-(}\text{p-}\text{nitrophenyl)}$ phosphate. This enzyme activity is distinct from the phosphodiesterase activity towards $\text{5′ -}\text{dTMP}\text{-p-}\text{nitrophenyl}$ ester, which is probably associated with intracellular membrane structure in platelets. Consequently, the use of the 4-methylumbelliferyl derivative as substrate for the phosphodiesterase activity provides a sensitive, fluorimetric assay for this marker enzyme of the platelet surface membrane.     

Bis-(4-methylumbelliferyl) phosphate as a substrate for the surface membrane-associated phosphodiesterase activity of pig platelets.

It was found that the newly-available compound, bis-(4-methylumbelliferyl) phosphate, could be used as a substrate for the pig platelet surface membrane-associated phosphodiesterase activity, usually assayed with bis-(p-nitrophenyl) phosphate. This enzyme activity is distinct from the phosphodiesterase activity towards 5'-dTMP-P-nitrophenyl ester, which is probably associated with intracellular membrane structures in platelets. Consequently, the use of the 4-methylumbelliferyl derivative as substrate for the phosphodiesterase activity provides a sensitive, fluorimetric assay for this marker enzyme of the platelet surface membrane.     

Comparison between a native and exotic adelgid as hosts for Laricobius rubidus (Coleoptera: Derodontidae)

Laricobius rubidus LeConte, native to eastern North America whose primary host is Pineus strobi Hartig, has been observed in association with Adelges tsugae, an exotic and lethal pest of hemlock trees in eastern North America. Pineus strobi and A. tsugae were used to evaluate host preference and suitability of this predatory beetle to determine in part its suitability as a potential biological control agent of A. tsugae. In a paired-choice oviposition test, L. rubidus preferred to oviposit in P. strobi ovisacs over those of A. tsugae. However, in the no-choice oviposition test, there was no significant difference in the mean number of eggs laid by L. rubidus females in P. strobi or A. tsugae ovisacs. There were no significant differences in larval developmental time or survivorship for L. rubidus reared on a diet of either P. strobi or A. tsugae. Laricobius rubidus completed development to the adult stage on A. tsugae indicating that it is a suitable host and therefore has the potential to contribute to biological control of A. tsugae in the eastern United States. The introduction of a congener, Laricobius nigrinus to eastern North America may result in competition with L. rubidus on A. tsugae, but the inability of L. nigrinus to complete development on P. strobi suggests that the two congeners will not compete on the primary host of L. rubidus.     

Comparison between the surface plasmon resonance (SPR) and the quartz crystal microbalance (QCM) method in a structural analysis of human endothelin-1

In this study, an automated surface plasmon resonance (SPR)-based biosensor was compared with a quartz crystal microbalance (QCM) biosensor. The two biosensor systems were used for characterizing a site-directed monoclonal antibody (mAb), raised against the C-terminal heptapeptide ET-1_15–21 of the human endothelin (ET-1). The mAb was characterized by its capacity for binding to ET-1, ET-3, Big.ET-1_22–38, the C-terminal (ET-1_15–21, ET-1_16–21, ET-1_17–21), and six derivates of ET-1_16–21, each containing a substitution with alanine (Ala) of a single aminoacid from position 16–21, respectively. The mAb reacted well with ET-1 and its fragments ET-1_15–21, ET-1_16–21, ET-1_17–21, but showed only a partial cross-reaction with ET-3, and did not bind human Big.ET-1_22–38. The Ala substitution on position 16,17, or 19 of ET-1_16–21 did not affect the antibody binding capacity of the hexapaptide ET-1_16–21. On the contrary, Ala substitution or Asp¹⁸, Ile²⁰ and particularly Trp²¹, inhibited its immunoreactivity. Thus the C-terminal represents an immunodominant epitope in ET-1 and is important for antibody binding. The SPR and QCM response signals were similar in shape but differing in time scales, reflecting differences in detection mechanisms. With regard to the fundamental problem of comparing different measurement principles, we found a good correlation between results obtained using the BIA technology and the QCM.     

Selective expression of the type 3 isoform of ryanodine receptor Ca2+ release channel (RyR3) in a subset of slow fibers in diaphragm and cephalic muscles of adult rabbits

The expression pattern of the RyR3 isoform of Ca2+ release channels was analysed by Western blot in neonatal and adult rabbit skeletal muscles. The results obtained show that the expression of the RyR3 isoform is developmentally regulated. In fact, RyR3 expression was detected in all muscles analysed at 2 and 15 days after birth while, in adult animals, it was restricted to a subset of muscles that includes diaphragm, masseter, pterygoideus, digastricus, and tongue. Interestingly, all of these muscles share a common embryonic origin being derived from the somitomeres or from the cephalic region of the embryo. Immunofluorescence analysis of rabbit skeletal muscle cross-sections showed that RyR3 staining was detected in all fibers of neonatal muscles. In contrast, in those adult muscles expressing RyR3 only a fraction of fibers was labelled. Staining of these muscles with antibodies against fast and slow myosins revealed a close correlation between expression of RyR3 and fibers expressing slow myosin isoform.     

Discovery of a novel murine keratin 6 (K6) isoform explains the absence of hair and nail defects in mice deficient for K6a and K6b

The murine genome is known to have two keratin 6 (K6) genes, mouse K6 (MK6)a and MK6b. These genes display a complex expression pattern with constitutive expression in the epithelia of oral mucosa, hair follicles, and nail beds. We generated mice deficient for both genes through embryonic stem cell technology. The majority of MK6a/b-/- mice die of starvation within the first two weeks of life. This is due to a localized disintegration of the dorsal tongue epithelium, which results in the build up of a plaque of cell debris that severely impairs feeding. However, approximately 25% of MK6a/b-/- mice survive to adulthood. Remarkably, the surviving MK6a/b-/- mice have normal hair and nails. To our surprise, we discovered MK6 staining both in the hair follicle and the nail bed of MK6a/b-/- mice, indicating the presence of a third MK6 gene. We cloned this previously unknown murine keratin gene and found it to be highly homologous to human K6hf, which is expressed in hair follicles. We therefore termed this gene MK6 hair follicle (MK6hf). The presence of MK6hf in the MK6a/b-/- follicles and nails offers an explanation for the absence of hair and nail defects in MK6a/b-/- animals.     

Optimisation of the surface electrostatics as a strategy for cold adaptation of uracil-DNA N-glycosylase (UNG) from Atlantic cod (Gadus morhua)

Cold-adapted enzymes are characterised by an increased catalytic efficiency and reduced temperature stability compared to their mesophilic counterparts. Lately, it has been suggested that an optimisation of the electrostatic surface potential is a strategy for cold adaptation for some enzymes. A visualisation of the electrostatic surface potential of cold-adapted uracil-DNA N-glycosylase (cUNG) from Atlantic cod indicates a more positively charged surface near the active site compared to human UNG (hUNG). In order to investigate the importance of the altered surface potential for the cold-adapted features of cod UNG, six mutants have been characterised and compared to cUNG and hUNG. The cUNG quadruple mutant (V171E, K185V, H250Q and H275Y) and four corresponding single mutants all comprise substitutions of residues present in the human enzyme. A human UNG mutant, E171V, comprises the equivalent residue found in cod UNG. In addition, crystal structures of the single mutants V171E and E171V have been determined. Results from the study show that a more negative electrostatic surface potential reduces the activity and increases the stability of cod UNG, and suggest an optimisation of the surface potential as a strategy for cold-adaptation of this enzyme. Val171 in cod UNG is especially important in this respect.     

Characterization and use of the total head soluble cholinesterases from mosquitofish (Gambusia holbrooki) for screening of anticholinesterase activity

Inhibition of cholinesterases (ChE) has been widely used as an environmental biomarker of exposure to organophosphates (OP) and carbamate (CB) pesticides. Different ChE isoforms may be present in the same tissue and may present distinct sensitivities towards environmental contaminants. The present work characterises the soluble ChE present in mosquitofish (Gambusia holbrooki) total head homogenates, through the use of different substrates and selective inhibitors of cholinesterasic activity. Furthermore, the effects of sodium dodecylsulphate (SDS) on the enzymatic activity were investigated, both in vivo and in vitro. These results showed that acetylcholinesterase (AChE) seemed to be the predominant form present in head homogenates of G. holbrooki, despite the inhibition by tetraisopropylpyrophosphoramide (iso-OMPA) found at high concentrations. SDS was responsible for in vitro, but not in vivo, inhibitory effects. The in vitro AChE inhibitory effects of SDS was partially prevented by the use of increasing amounts of ethanol, suggesting that the inhibition was induced by an emulsion effect, which may explain the lack of effect in vivo.     

Preliminary report on a method for establishing the relation between the surface of a plantar load and the total projective surface of the foot: index of plantar load (IPL)

The creation of a Plantar Load Index (PLI) is proposed, with a view to studying the plantar surface of the foot from a morphofunctional standpoint. This Index would provide information on the centesimal relationship between the surface load values and the total projective values of the foot, expressed in cm2. The measurements in question are homogeneous in nature and may, therefore, be easily related to one another. To obtain these values, the two surfaces are visualized, photographed together in a single photogram and analyzed by means of the computerized visual system (Zeiss Videoplan). Visualization is obtained by means of a thermochromatic variation plate which is placed on the stand of a reflexion podoscope and which is sensitive to the heat of the plantar skin and the suitably emitted infra-red rays. The heat of the skin in contact with the plate shows the load surface. The intra-red rays suitably emitted from above onto the plate and onto the back of the foot produce the general chromatic variation of the plate, also showing the perimetrical outline of the foot. The picture to be photographed will, then, be as follows: a continuous black edge formed from the outside by the colouring of the plate produced by the infra-red rays (the perimeter of the foot); more black, extending inwards, in varying degrees, when the skin is not touching the plate (the archer and furrows in the skin); coloured areas inside of the perimeter, showing the load surface.(ABSTRACT TRUNCATED AT 250 WORDS)     

QOL models constructed for the community-dwelling elderly with ikigai (purpose in life) as a composition factor, and the effect of habitual exercise

The purpose of this study was to construct QOL models for the elderly that included ikigai as a composition factor and to clarify differences in two kinds of models, one constructed for the elderly with habitual exercise and the other for those without it.The subjects were 1,566 healthy community-dwelling independent people aged 60 years or more (752 males, 814 females). First, the ratio of subjects with ikigai was calculated. The ratios of subjects with different kinds of objects of ikigai were also calculated. Next, structural equation models (SEM) were constructed on the basis of social, physical, and mental QOL and ikigai. Fits of the models were evaluated. To examine whether the presence or absence of habitual exercise caused any difference in the QOL model, subjects were divided into 4 groups according to whether they were male or female and whether they had or did not have an exercise habit. Multi-population group simultaneous analysis was then performed among the four groups.More than 85% of the subjects had objects of ikigai. Ikigai is an important factor for comprehending the QOL of the elderly. It was possible to construct QOL models for the elderly with ikigai as a composition factor. The effect of physical QOL on mental QOL was negligible in females irrespective of whether they had an exercise habit. The effect of social QOL on mental QOL was profound in aged females with an exercise habit. The effect of the living situation on mental QOL was profound in aged females without an exercise habit. The effect of mental QOL on ikigai was more marked in subjects without an exercise habit than in those with an exercise habit.     

Evaluation of a peripherally selective antiandrogen (Casodex) as a tool for studying the relationship between testosterone and spermatogenesis in the rat.

The endocrine profile and the effects on spermatogenesis of the new antiandrogen, Casodex [2RS)-4-cyano-3-(4-fluorophenylsulphonyl)-2-anilide, CAS) were evaluated in the adult rat. In the first experiment rats were administered CAS at daily doses of 10, 20 and 40 mg/kg for 14 days. For comparison groups receiving flutamide (FL, 10 mg/kg) and ethane dimethane sulphonate (EDS) were included. Unlike FL, administration of CAS (10 and 20 mg/kg) did not significantly raise serum concentrations of gonadotropic hormones and testosterone. With 40 mg/kg CAS gonadotropin secretion, but not testosterone levels, were elevated on day 15. Administration of CAS lowered the weight of the seminal vesicles and coagulating glands comparable to the administration of the Leydig cell toxin EDS. In contrast to FL a significant loss of germ cells in stage VII of spermatogenesis was observed with CAS. In a second experiment the ability of FL and CAS to block testicular androgen action was compared in rats with reduced testicular androgen production induced by a gonadotropin-releasing hormone antagonist. Both antiandrogens markedly enhanced spermatogenic involution as revealed by quantitative flow cytometric analysis of germ cell numbers. The study demonstrates that (a) CAS is a peripherally selective antiandrogen and (b) CAS might provide a feasible approach to study androgen dependence of spermatogenesis in the presence of normal FSH levels.     

Ultracytochemistry as a tool for the study of the cellular and subcellular localization of membrane-bound guanylate cyclase (GC) activity. Applicability to both receptor-activated and receptor-independent GC activity

Membrane-bound guanylate cyclase activity was detected by ultracytochemistry at the electron microscope level in several mammalian tissues. The technique used in these studies allows the detection of active enzyme at the membrane site where it is located. In a few cases, such as normal and regenerating peripheral nerves and placenta, membrane-bound guanylate cyclase could be detected in the absence of stimulators of enzyme activity. However, in the majority of these studies membrane-bound guanylate cyclase was investigated following stimulation with natriuretic peptides, guanylin, or the Ca²⁺ sensor proteins, S100B and S100A1. In general, membrane-bound guanylate cyclase was localized to plasma membranes, in accordance with the functional role of this enzyme. Yet, in secretory cells the enzyme activity was localized on intracellular membranes, suggesting a role of membrane-bound guanylate cyclase in secretory processes. Finally, S100B and S100A1 were found to colocalize with membrane-bound guanylate cyclase on photoreceptor disc membranes and to stimulate enzyme activity at these sites in dark-adapted retinas in a Ca²⁺-dependent manner. The results of these analyses are discussed in relation to the proposed functional role(s) of this enzyme.     

Effects of divalent metal ions on the alphaB-crystallin chaperone-like activity: spectroscopic evidence for a complex between copper(II) and protein

AlphaB-crystallin is a small heat shock protein, showing chaperone-like activity, that is expressed in the lens and in several other tissues. The role of some metal ions in the alphaB-crystallin biology starts to be well documented. In some neuro-degenerative pathologies, like Parkinson and Alzheimer's diseases, alphaB-crystallin is expressed at high levels. In the same pathologies an accumulation of divalent metal cations is observed. In order to investigate the interactions between human alphaB-crystallin and divalent metal ions, the effect of copper, zinc and calcium on the chaperone-like activity of the protein has been studied. Copper and zinc at concentrations 0.1 and 1 mM significantly increase the chaperone-like activity, whereas calcium 1 mM completely inhibits activity. Electron paramagnetic resonance (EPR) and circular dichroism (CD) spectra indicate the possible complex formation between Cu(II) and protein at physiological pH. Molecular modeling calculations, carried out for the probable Cu(II) binding site, suggest that a complex with three histidine residues is possible.     

Relevance of the leaving group for antitumor activity of new platinum(II) compounds containing anthracene derivatives as a carrier ligand

A new anticancer-active platinum(II) compound [Pt(A9pyp)(dmso)(cbdca)], containing the E-1-(9-anthryl)-3-(2-pyridyl)-2-propenone ligand (abbreviated as A9pyp) has been synthesized by the replacement of the anionic chloride ligands in cis-[Pt(A9pyp)(dmso)Cl₂] by the dianionic chelating cyclobutanedicarboxylate ligand (abbreviated as cbdca). The in vitro relevance of the leaving group of these new platinum(II) compounds has been investigated. Measurements of the time-dependent intracellular accumulation of both compounds in human ovarian carcinoma cell lines show that the leaving group affects their cellular uptake. In addition, the leaving group also influences DNA platination, and, therefore, has an effect on the biological activity against a pair of human ovarian carcinoma cell lines, i.e. sensitive and resistant to cisplatin.     

Comparison of Acyrthosiphon pisum (Homoptera: Aphididae) and Frankliniella occidentalis (Thysanoptera: Thripidae) as prey for the development and survival of Chrysopa pallens (Neuroptera: Chrysopidae)

The effects of two different prey species on the pre-imaginal development and survival of the green lacewing, Chrysopa pallens were determined under laboratory conditions. The developmental duration from first instar to adult emergence was shorter when larvae were fed on Acyrthosiphon pisum (22.56 ± 0.39 d) than on Frankliniella occidentalis (29 ± 0.45 d). The survival rate of lacewings from first instar to adult emergence was 22.6% higher when they were fed on A. pisum than when fed on F. occidentalis. The possible implications of these findings are applicable to mass-rearing of C. pallens and for understanding predator's biology and survival capacity in the presence of prey species evaluated and could be used in the development of an effective biological control program.     

Multiple spectroscopic studies of the interaction between a quaternary ammonium-based cationic Gemini surfactant (as a carrier) and human erythropoietin

Erythropoietin (EPO) is a hematopoietic growth factor. This substance, as a strong cell protector, can increase cell maintenance during different damages of central nervous system. Since the brain-blood barrier prevents the entrance of large proteins similar to EPO into the brain, its systemic delivery gets limited. The aim of this study was to find an alternative approach for EPO delivery into the brain to skip the blood-brain barrier prevention. So, a new quaternary ammonium-based cationic Gemini surfactant has been used to study the interaction of the cationic Gemini surfactant (as a carrier) with EPO using various spectroscopic techniques of (fluorescence and circular dichroism (CD)) and thermal denaturation. Fluorescence spectroscopy studies show the formation of Gemini-EPO complex and also static quenching of protein upon this interaction. The binding parameters of number of binding sites, binding affinity, Gibbs free energy, enthalpy, and entropy were calculated according to fluorescence quenching studies. Also, CD results have further represented that the content of regular secondary structure of EPO did not show any significant alterations by increasing the Gemini concentration. Finally, thermal denaturation behavior of EPO results indicates decreasing the thermal stability of protein in the presence of Gemini. In conclusion, the obtained results proposed that Gemini as a cationic surfactant can bind to EPO without any significant diverse effects on the structure of this drug (EPO) which can be considered as a candidate for EPO delivery in future.