Complication Pattern After Percutaneous Cement Discoplasty: Identification of Factors Influencing Reoperation and Length of Hospital Stay.

OBJECTIVE: Percutaneous cement discoplasty (PCD) was introduced to treat symptomatic vertical instability of the lumbar spine in a minimally invasive way. The aim of the present study was to analyze the complication pattern after PCD and to identify factors that predict the chance of cement leakage, reoperation, and length of hospital stay (LOS). METHODS: patients were treated with PCD within the study period. Clinical features and complications were analyzed by applying descriptive statistics, whereas perioperative factors predictive of cement leakage, reoperation, and LOS were identified by regression models. RESULTS: Cement leakage rate was 30.4% in the total cohort; however, only fifth of them were symptomatic. Cement leakage itself did not have a significant influence on clinical outcome. Other complications and nonsurgical adverse events were registered only in 2.0% of cases. Age, subcutaneous fat tissue thickness, low viscosity cement, lower level of surgeon's experience and the number of operated levels were identified as risk factors of cement leakage (P < 0.01; c-index = 0.836). Type of procedure, Charlson comorbidity score, reoperation, and nonsurgical adverse events significantly increased the LOS (P < 0.01). Cement leakage, early surgical practice, and increased subcutaneous fat tissue thickness were risk factors for reoperation (P < 0.01; c-index = 0.72). CONCLUSIONS: PCD is a relatively safe and effective procedure for treating spinal instability caused by advanced-stage disc degeneration characterized by vacuum phenomenon. Cement leakage is not uncommon but is only a radiologic complication without clinical consequences in most cases. On the other hand, it can increase the LOS and is a significant risk factor for reoperation.

A novel three-dimensional volumetric method to measure indirect decompression after percutaneous cement discoplasty.

PURPOSE: Percutaneous cement discoplasty (PCD) is a minimally invasive surgical option to treat patients who suffer from the consequences of advanced disc degeneration. As the current two-dimensional methods can inappropriately measure the difference in the complex 3D anatomy of the spinal segment, our aim was to develop and apply a volumetric method to measure the geometrical change in the surgically treated segments. METHODS: Prospective clinical and radiological data of 10 patients who underwent single- or multilevel PCD was collected. Pre- and postoperative CT scan-based 3D reconstructions were performed. The injected PMMA (Polymethylmethacrylate) induced lifting of the cranial vertebra and the following volumetric change was measured by subtraction of the geometry of the spinal canal from a pre- and postoperatively predefined cylinder. The associations of the PMMA geometry and the volumetric change of the spinal canal with clinical outcome were determined. RESULTS: Change in the spinal canal volume (ΔV) due to the surgery proved to be significant (mean ΔV = 2266.5 ±â€¯1172.2 mm3, n = 16; p = 0.0004). A significant, positive correlation was found between ΔV, the volume and the surface of the injected PMMA. A strong, significant association between pain intensity (low back and leg pain) and the magnitude of the volumetric increase of the spinal canal was shown (ρ = 0.772, p = 0.009 for LBP and ρ = 0.693, p = 0.026 for LP). CONCLUSION: The developed method is accurate, reproducible and applicable for the analysis of any other spinal surgical method. The volume and surface area of the injected PMMA have a predictive power on the extent of the indirect spinal canal decompression. The larger the ΔV the higher clinical benefit was achieved with the PCD procedure. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: The developed method has the potential to be integrated into clinical software's to evaluate the efficacy of different surgical procedures based on indirect decompression effect such as PCD, anterior lumbar interbody fusion (ALIF), lateral lumbar interbody fusion (LLIF), oblique lumbar interbody fusion (OLIF), extreme lateral interbody fusion (XLIF). The intraoperative use of the method will allow the surgeon to respond if the decompression does not reach the desired level.

Indirect foraminal decompression and improvement in the lumbar alignment after percutaneous cement discoplasty.

PURPOSE: Percutaneous cement discoplasty (PCD) is a minimally invasive surgical procedure, that can provide a segmental stabilizing and indirect decompression effect in case of severely degenerated discs characterized by vacuum phenomenon. The objective of this study was to evaluate the effects of PCD on spinopelvic radiological parameters and their associations with the clinical outcome. METHODS: Retrospective analysis of prospectively collected dataset of 28 patients (112 lumbar segments) who underwent single- or multilevel PCD was performed. Spinopelvic, intrasegmental and intersegmental parameters were measured on lumbar X-rays pre-, postoperatively and 6 months after the surgery. Correlations between radiological parameters and clinical outcome data were determined. RESULTS: Sacral slope significantly increased (p < .001), and pelvic tilt (p < .05) was decreased after the PCD procedure. Segmental and total lordosis (p < .05, p < .05) disc and foraminal height showed significantly increase (p < .001, p < .001) after procedure. Pain and disability (ODI) significantly decreased due to PCD. An association was found between postoperative increase in SS and improvement in ODI (r = 0.39, p < .05). The change in low back pain was correlated with segmental scoliosis correction (p < .001). Moderate correlation was detected between the increase in disc height and ODI (p < .05) as well as leg pain (p < .01). CONCLUSION: PCD is an effective minimally invasive technique to treat axial pain and disability related to severe lumbar disc degeneration. Our study shows that an improvement in lumbar alignment and a significant indirect foraminal decompression could be achieved with the procedure. These changes can significantly contribute to the pain relief and increase in the patients' functional capacity. These slides can be retrieved under Electronic Supplementary Material.

Single-dose ß-aminobutyric acid treatment modifies tobacco (Nicotiana tabacum L.) leaf acclimation to consecutive UV-B treatment.

ß-Aminobutyric acid (BABA) pre-treatment has been shown to alter both biotic and abiotic stress responses. The present study extends this observation to acclimative UV-B-response, which has not been explored in this context so far. A single soil application of 300 ppm BABA modified the non-enzymatic antioxidant capacities and the leaf hydrogen peroxide levels in tobacco (Nicotiana tabacum L.) leaves in response to a 9-day treatment with 5.4 kJ m-2 d-1 biologically effective supplementary UV-B radiation in a model experiment that was performed in a growth chamber. BABA decreased leaf hydrogen peroxide levels both as a single factor and in combination with UV-B, but neither BABA nor UV-B affected leaf photochemistry significantly. The total antioxidant capacities were increased by either BABA or UV-B, and this response was additive in BABA pre-treated leaves. These results together with the observed changes in hydroxyl radical neutralising ability and non-enzymatic hydrogen peroxide antioxidant capacities show that BABA pre-treatment (i) has a long-term effect on leaf antioxidants even in the absence of other factors and (ii) modifies acclimative readjustment of prooxidant-antioxidant balance in response to UV-B. BABA-inducible antioxidants do not include phenolic compounds as a UV-B-induced increase in the adaxial leaf flavonoid index and total leaf extract UV absorption were unaffected by BABA.

Nanostructured TiO2-induced photocatalytic stress enhances the antioxidant capacity and phenolic content in the leaves of Vitis vinifera on a genotype-dependent manner.

Over the past decades, nanotechnology has received great attention and brought revolutionary solutions for a number of challenges in scientific fields. Industrial, agricultural and medical applications of engineered nanomaterials have increased intensively. The ability of titanium dioxide nanoparticles (TiO2 NPs) to produce reactive oxygen species (ROS), when excited by ultra-violet (UV) light, makes them useful for effectively inactivate various pathogens. It is known that ROS also have signalling role in living organisms, therefore, TiO2 NPs-induced ROS can influence both enzymatic and non-enzymatic defence systems, and could play a role in the resistance of plants to pathogens. Herein, we studied the photocatalytic stress responses of grapevine (Vitis vinifera L.) as model plant, when exposed to a well-known photocatalyst, Degussa P25 TiO2 NPs. The photocatalytically produced ROS such as superoxide anion, hydroxyl radical and singlet oxygen were confirmed by electron paramagnetic resonance spectroscopy. Foliar exposure of five red cultivars (Cabernet sauvignon, Cabernet franc, Merlot, Kékfrankos and Kadarka) was carried out in blooming phenophase under field condition where plants are exposed to natural sunlight with relatively high UV radiation (with a maximum of ~ 45 W m-2). After two weeks of exposure, the effects of photogenerated ROS on the total phenolic content, antioxidant capacity, flavonol profile and the main macro-, microelements of the leaves were studied in detail. We found that foliar application of TiO2 NPs boosted the total phenolic content and biosynthesis of the leaf flavonols depending on the grapevine variety. Photocatalytically active TiO2 NPs also increased K, Mg, Ca, B and Mn levels in the leaves as shown by ICP-AES measurements.

Environmental Factors Correlated with the Metabolite Profile of Vitis vinifera cv. Pinot Noir Berry Skins along a European Latitudinal Gradient.

Mature berries of Pinot Noir grapevines were sampled across a latitudinal gradient in Europe, from southern Spain to central Germany. Our aim was to study the influence of latitude-dependent environmental factors on the metabolite composition (mainly phenolic compounds) of berry skins. Solar radiation variables were positively correlated with flavonols and flavanonols and, to a lesser extent, with stilbenes and cinnamic acids. The daily means of global and erythematic UV solar radiation over long periods (bud break-veraison, bud break-harvest, and veraison-harvest), and the doses and daily means in shorter development periods (5-10 days before veraison and harvest) were the variables best correlated with the phenolic profile. The ratio between trihydroxylated and monohydroxylated flavonols, which was positively correlated with antioxidant capacity, was the berry skin variable best correlated with those radiation variables. Total flavanols and total anthocyanins did not show any correlation with radiation variables. Air temperature, degree days, rainfall, and aridity indices showed fewer correlations with metabolite contents than radiation. Moreover, the latter correlations were restricted to the period veraison-harvest, where radiation, temperature, and water availability variables were correlated, making it difficult to separate the possible individual effects of each type of variable. The data show that managing environmental factors, in particular global and UV radiation, through cultural practices during specific development periods, can be useful to promote the synthesis of valuable nutraceuticals and metabolites that influence wine quality.

Protein and alkaloid patterns of the floral nectar in some solanaceous species.

The family Solanaceae includes several melliferous plants, which tend to produce copious amounts of nectar. Floral nectar is a chemically complex aqueous solution, dominated by sugars, but minor components such as amino acids, proteins, flavonoids and alkaloids are present as well. This study aimed at analysing the protein and alkaloid profile of the nectar in seven solanaceous species. Proteins were examined with SDS-PAGE and alkaloids were analyzed with HPLC. The investigation of protein profile revealed significant differences in nectar-protein patterns not only between different plant genera, but also between the three Nicotiana species investigated. SDS-PAGE suggested the presence of several Nectarin proteins with antimicrobial activity in Nicotiana species. The nectar of all tobacco species contained the alkaloid nicotine, N. tabacum having the highest nicotine content. The nectar of Brugmansia suaveolens, Datura stramonium, Hyoscyamus niger and Lycium barbarum contained scopolamine, the highest content of which was measured in B. suaveolens. The alkaloid concentrations in the nectars of most solanaceous species investigated can cause deterrence in honeybees, and the nectar of N. rustica and N. tabacum can be considered toxic for honeybees.

Dissecting the beta-aminobutyric acid-induced priming phenomenon in Arabidopsis.

Plants treated with the nonprotein amino acid beta-aminobutyric acid (BABA) develop an enhanced capacity to resist biotic and abiotic stresses. This BABA-induced resistance (BABA-IR) is associated with an augmented capacity to express basal defense responses, a phenomenon known as priming. Based on the observation that high amounts of BABA induce sterility in Arabidopsis thaliana, a mutagenesis screen was performed to select mutants impaired in BABA-induced sterility (ibs). Here, we report the isolation and subsequent characterization of three T-DNA-tagged ibs mutants. Mutant ibs1 is affected in a cyclin-dependent kinase-like protein, and ibs2 is defective in AtSAC1b encoding a polyphosphoinositide phosphatase. Mutant ibs3 is affected in the regulation of the ABA1 gene encoding the abscisic acid (ABA) biosynthetic enzyme zeaxanthin epoxidase. To elucidate the function of the three IBS genes in plant resistance, the mutants were tested for BABA-IR against the bacterium Pseudomonas syringae pv tomato, the oomycete Hyaloperonospora parasitica, and BABA-induced tolerance to salt. All three ibs mutants were compromised in BABA-IR against H. parasitica, although to a different extent. Whereas ibs1 was reduced in priming for salicylate (SA)-dependent trailing necrosis, mutants ibs2 and ibs3 were affected in the priming for callose deposition. Only ibs1 failed to express BABA-IR against P. syringae, which coincided with a defect in priming for SA-inducible PR-1 gene expression. By contrast, ibs2 and ibs3 showed reduced BABA-induced tolerance to salt, which correlated with an affected priming for ABA-inducible gene expression. For all three ibs alleles, the defects in BABA-induced sterility and BABA-induced protection against P. syringae, H. parasitica, and salt could be confirmed in independent mutants. The data presented here introduce three novel regulatory genes involved in priming for different defense responses.

Neuropathology of white matter disease in Leber's hereditary optic neuropathy.

Leber's hereditary optic neuropathy (LHON) is associated with point mutations in the mitochondrial DNA (mtDNA), coding for a mitochondrial respiratory chain complex I subunit. It is characterized by bilateral, usually sequential, optic neuropathy and may co-occur with multiple sclerosis-like white matter lesions. Despite repeated clinical reports including MRI and histopathological examination of the visual system, neuropathological descriptions of LHON associated with multiple sclerosis-like syndrome are lacking. We present here the case of a female patient with a point mutation at nucleotide position T14484C, who suffered from relapsing episodes of visual loss of both eyes and consecutively developed Hashimoto thyroiditis as well as widespread demyelinating CNS lesions outside the visual system. She died of bronchopneumonia at the age of 44 years, after a disease duration of 19 years, with progressive deterioration, epileptic seizures and immobility. Immunohistochemical analysis on formalin-fixed and paraffin-embedded tissue reveals a spectrum of neuropathological changes, including actively and inactively demyelinating plaques in the white matter and optic nerve, vacuolation and cystic necrosis with CD8-positive T cells in the frontal lobe, axonal damage, and vacuolation of white matter. Tissue destruction is associated with upregulation of mitochondrial manganese superoxide dismutase within the lesions and an increase in the expression of inducible nitric oxide synthase within macrophages and microglia. This variable phenotype of extraoptic LHON disease suggests that mtDNA mutations may affect the nervous system on a common metabolic basis and occasionally may aggravate or initiate autoimmune pathology.