Validation of the Polish language version of the SF-36 Health Survey in patients suffering from lumbar spinal stenosis

Introduction and objective. Patient-reported outcome (PRO) questionnaires have become the standard measure for treatment effectiveness after spinal surgery. One of the most widely used generic PROs is the SF-36 Health Survey. The aim of this study was to specifically focus on validating the SF-36 Health Survey to confirm that the tool is an acceptable and psychometrically robust measure to collect HRQoL data in Polish patients with spinal stenosis. Materials and Methods. Patients were eligible if they were above 18 years of age and had been qualified for spine surgery of the lumbar region due to either discopathy or non-traumatic spinal stenosis. All patients filled-in the Polish version of the SF-36 and a demographic questionnaire. Standard validity and reliability analyses were performed. Results. 192 patients (83 women – 43.2%) agreed to take part in the study (mean age: 57.5±11.4 years). In 47 patients (24.5%), using MRI, ossification of the ligamenta flava were found. Cronbach’s alpha coefficients showed positive internal consistency (0.70–0.92). Interclass correlations for the SF-36 ranged from 0.72 – 0.86 and proved appropriate test-retest reliability. Satisfactory convergent and discriminant validity in multi-trait scaling analyses was seen. Conclusions. The Polish version of the SF-36 is a reliable and valid tool for measuring HRQoL in patients with spinal stenosis. It can be recommended for use in clinical and epidemiological settings in the Polish population. However, caution is warranted when interpreting the results of the ‘role limitations due to physical health problems’ and the ‘role limitations due to emotional problems’ scales because of floor and ceiling effects

Ossification of the ligamentum flavum of the lumbosacral spine in the polish hospitalized population : a prospective cohort study

The aim of this study was to assess the prevalence, clinical features and distribution of lumbosacral ossifications of the ligamentum flavum (OLF), using MRI, CT and microCT, in hospitalized Polish patients. Patients were recruited prospectively between January 2011 and January 2013. Patients were further qualified to the study group only if CT or MRI of the lumbosacral region detected OLF. Level of OLF excision was determined by the localization of spinal stenosis. After excision the LF fragments containing OLF were stored in a 4% solution of formaldehyde until microCT assessment. A total of 184 agreed to take part in the study. In 50 patients (27.2%) OLF were found. Thus, the study group consisted of 17 women (34%) and 33 men, with a mean age of 55.4 \pm 17.2 years. OLF occurred more often in men (66%) than in women (34%) (p = 0.0014). The most common site for the localization of OLF in women, as well as in men was the L5/S1 level (60% and 53.3% respectively). The mean volume of OLF was 3.87\pm 5.27 mm^{3}\left ( 4.66 \pm 5.71 mm^{3} vs. 1.27 \pm 2.19 mm^{3}, in men and women respectively; p = 0.023 \right ). The LF were thickened in 21 (42%) patients. The mean volume of OLF in patients with normal LF was 4.78\pm 5.95 mm^{3} and in patients with thickened LF 5.33\pm 6.10 mm^{3} (p = 0.75). The prevalence of lumbosacral OLF in the Polish hospitalized population is very high. The most common site of their localization is the L5/S1 level. LF thickening is not associated with OLF formation

Rare collapse of fermionic quasiparticles upon coupling to local bosons

We study the stability of the fermionic quasiparticle in a fermion-boson model on a Bethe lattice, with fermions interacting with local bosons via a polaronic-type coupling. We solve the problem by mapping it onto a non-interacting chain with site-dependent potential. We show that, despite a finite number of bosonic excitations costing zero energy, among the many analyzed cases, the occurrence of a complete collapse of the quasiparticle is rare. The quasiparticle disappearance becomes easier with an increase in: (i) the total number of bosons with zero energy, and (ii) the relative strength of the coupling between bosons and fermions. The postulated model can, among other things, be applied to study systems in which fermions are introduced into antiferromagnetic (or antiferro-orbital) domains surrounded by ferromagnetic (or ferro-orbital) ordered states. This might take place in the overdoped cuprates or upon doping manganese or vanadium oxides. Finally, we show how this model leads to an in-depth understanding of the onset of quasiparticles in the 1D and 2D $t$-$J^z$ model.Comment: 14 pages, 9 figures, 2 Appendice

Validation of the Polish language version of the SF-36 Health Survey in patients suffering from lumbar spinal stenosis

[b]introduction and objective[/b]. Patient-reported outcome (PRO) questionnaires have become the standard measure for treatment effectiveness after spinal surgery. One of the most widely used generic PROs is the SF-36 Health Survey. The aim of this study was to specifically focus on validating the SF-36 Health Survey to confirm that the tool is an acceptable and psychometrically robust measure to collect HRQoL data in Polish patients with spinal stenosis. [b]materials and methods[/b]. Patients were eligible if they were above 18 years of age and had been qualified for spine surgery of the lumbar region due to either discopathy or non-traumatic spinal stenosis. All patients filled-in the Polish version of the SF-36 and a demographic questionnaire. Standard validity and reliability analyses were performed. [b]results.[/b] 192 patients (83 women – 43.2%) agreed to take part in the study (mean age: 57.5±11.4 years). In 47 patients (24.5%), using MRI, ossification of the ligamenta flava were found. Cronbach’s alpha coefficients showed positive internal consistency (0.70–0.92). Interclass correlations for the SF-36 ranged from 0.72 – 0.86 and proved appropriate test-retest reliability. Satisfactory convergent and discriminant validity in multi-trait scaling analyses was seen. [b]conclusions.[/b] The Polish version of the SF-36 is a reliable and valid tool for measuring HRQoL in patients with spinal stenosis. It can be recommended for use in clinical and epidemiological settings in the Polish population. However, caution is warranted when interpreting the results of the ‘role limitations due to physical health problems’ and the ‘role limitations due to emotional problems’ scales because of floor and ceiling effects

Ossification of the ligamentum flavum of the lumbosacral spine in the Polish hospitalized population - a prospective cohort study

The aim of this study was to assess the prevalence, clinical features and distribution of lumbosacral ossifications of the ligamentum flavum (OLF), using MRI, CT and microCT, in hospitalized Polish patients. Patients were recruited prospectively between January 2011 and January 2013. Patients were further qualified to the study group only if CT or MRI of the lumbosacral region detected OLF. Level of OLF excision was determined by the localization of spinal stenosis. After excision the LF fragments containing OLF were stored in a 4% solution of formaldehyde until microCT assessment. A total of 184 agreed to take part in the study. In 50 patients (27.2%) OLF were found. Thus, the study group consisted of 17 women (34%) and 33 men, with a mean age of 55.4 \pm 17.2 years. OLF occurred more often in men (66%) than in women (34%) (p = 0.0014). The most common site for the localization of OLF in women, as well as in men was the L5/S1 level (60% and 53.3% respectively). The mean volume of OLF was 3.87\pm 5.27 mm^{3}\left ( 4.66 \pm 5.71 mm^{3} vs. 1.27 \pm 2.19 mm^{3}, in men and women respectively; p = 0.023 \right ). The LF were thickened in 21 (42%) patients. The mean volume of OLF in patients with normal LF was 4.78\pm 5.95 mm^{3} and in patients with thickened LF 5.33\pm 6.10 mm^{3} (p = 0.75). The prevalence of lumbosacral OLF in the Polish hospitalized population is very high. The most common site of their localization is the L5/S1 level. LF thickening is not associated with OLF formation

Near-shore distribution of alien Ponto-Caspian amphipods in a European dam reservoir in relation to substratum type and occurrence of macroinvertebrate taxa

Knowledge of habitat requirements and interspecific interactions of invasive species helps predict their impact and spread. We determined the relationships within the invasive freshwater Ponto-Caspian amphipod assemblage, and their associations with macroinvertebrates in the near-shore zone of a central European lowland dam reservoir. We sampled five habitat types: bare sand at the water line, bare sand (0.2 m depth), bare sand (0.5 m depth), macrophyte-overgrown sand (1 m depth), stones (0.3 m depth) on four dates (October 2015–October 2016). Pontogammarus robustoides occurred in all habitats, Dikerogammarus villosus and Echinogammarus ischnus were limited to the stony bottom. Amphipod densities were positively associated with one another except Dikerogammarus juveniles, negatively correlated with adults. The occurrence of D. villosus, juvenile Dikerogammarus and E. ischnus was positively related to the presence of the shelter-forming bivalve Dreissena polymorpha. Pontogammarus robustoides was positively associated with sphaeriid clams and gastropods (shelters), as well as oligochaetes and chironomids (potential prey items). Dikerogammarus villosus and E. ischnus were positively related to chironomids and oligochaetes, respectively. Coexistence of various alien amphipods in the studied area, indicated by prevailing positive relationships in their assemblage, may be enabled by the abundance of shelters and rich food sources allowing habitat partitioning

Synthesis and potential cytotoxicity evaluation of carboxymethyl chitosan hydrogels

The aim of the research was to employ radiation to produce flexible carboxymethyl chitosan (CMCS) based hydrogels of uniform structure to characterise their swelling properties and cytocompatibility for potential applications as hydrogel wound dressings. CMCS in aqueous solution was irradiated with an electron beam in the presence of a poly(ethylene glycol) diacrylate (PEGDA) macromonomer as a crosslinker, at 12 different compositions, i.e. 3–20% CMCS, 3 and 5% PEGDA. The obtained hydrogels were subjected to sol–gel analysis. The amount of insoluble fraction (up to 100%) rose with an increase in the PEGDA/polysaccharide ratio. Moreover, the equilibrium degree of swelling, ca. 15 to 200 g of water per g of gel, which was higher for lower content of crosslinker, decreased with the delivered dose, which was associated with an increase in crosslinking density. The in vitro XTT cell viability assay (murine fibroblasts, L929 cell line) showed no significant cytotoxicity of CMCS gels

Carboxymethyl Chitosan Hydrogels for Effective Wound Healing—An Animal Study

Hydrogels have various applications in medicine, for example, in systems for controlled drug release or as wound dressings, where they provide an appropriate environment for healing and constitute a barrier to microorganisms. The aim of this study was to evaluate the action of carboxymethyl chitosan (CMCS) hydrogels in wound healing therapy in vivo using a laboratory rat model. The hydrogels were formed from aqueous solutions of a CMCS biopolymer via electron beam irradiation, with the presence of a crosslinking agent of poly(ethylene glycol) diacrylate. A histopathological examination of injured tissue, using a model of a hard-to-heal wound, indicated that the CMCS hydrogel supported healing. The new gel dressing, being noncytotoxic, presents great potential in wound treatment, with positive effects on the amount of inflammatory infiltration, young collagen formation, and the degree of epidermalization. A key advantage of the current approach (i.e., using competitive radiation technology for synthesis) is that it includes only one step, with the product being sterilized as it is synthesized. The hydrogel effectively supports wound healing and can serve as a bio-based and biodegradable platform for other medical applications