Efficacy and Complication Rates of Percutaneous Vertebroplasty and Kyphoplasty in the Treatment of Vertebral Compression Fractures: A Retrospective Analysis of 280 Patients.

Background: Percutaneous vertebroplasty (PVP) and kyphoplasty (PKP) are established methods in the treatment of vertebral compression fractures (VCFs). In our manuscript, the target was to evaluate the efficacy of PVPs/PKPs and to determine the implications of potential periprocedural complications. Methods: 280 patients, specifically 194 women (69.3%) and 86 men (30.7%), were enrolled. We used the AO spine fractures classification and the Yeom classification to determine the subtype of cement leakage. Only single-level VCFs of the thoracic or lumbar spine were included. Visual analogue scale (VAS) was assessed preoperatively and regularly after the surgery. Vertebral compression ratio (VBCR) was used to determine postoperative vertebral body collapse. Results: We recorded 54 cases (19.3%) of cement leakage. There was a significant decrease in mean VAS scores (6.82-0.76 in PVPs, 7.15-0.81 in PKPs). The decrease in VBCR was greater in the VP group (4.39%; 84.21-79.82) compared to the KP group (1.95%; 74.36-72.41). Conclusions: No significant difference in the risk of cement leakage when comparing KPs and VPs was found. VPs and KPs provide rapid and significant pain relief in patients with VCFs. Clinically relevant complications of VPs and KPs are rare. Kyphoplasties prevent further vertebral body collapse more effectively compared to vertebroplasties.

Current Approaches to Osteoid Osteoma and Minimally Invasive Surgery-A Minireview and a Case Report.

Osteoid osteoma is a benign bone tumor typically affecting the long bones of the lower limbs in young male patients. The lesion can be asymptomatic but, in most cases, patients present with characteristic nocturnal pain that is very responsive to the administration of non-steroidal anti-inflammatory drugs. Although osteoid osteomas can regress spontaneously over time, surgical therapy is often indicated in cases of long-lasting resistant pain. Apart from a traditional open resection, the modalities of minimally invasive surgery, such as radiofrequency ablation or cryoablation, have gradually become the option of choice in most cases. The first part of this manuscript is a minireview of the contemporary literature on the pathogenesis, diagnosis, and current trends in the treatment of osteoid osteoma. The second part is a case report of our own experience with a conventional C-arm-guided radiofrequency ablation of an osteoid osteoma located in the femoral neck in an adolescent patient. The aim was to prove that, even when more sophisticated guiding devices (CT, O-arm, etc.) are not available, the safe and reliable ablation of the lesion using a C-arm is still possible even in hard-to-reach areas. The case was a success, with no perioperative or postoperative complications.

A Successful Case of TKA With Complex Deformity And Retained Hardware Using Computer Navigation.

We present a case report of a 60-year-old Caucasian female patient, who had undergone a series of procedures for a periprosthetic (after total hip arthroplasty) Vancouver C type diaphyseal fracture of the right femur (reverse distal femoral locking compression plate [LCP] osteosynthesis, then a corrective osteotomy with another distal femoral LCP osteosynthesis). Subsequently, she developed high-grade osteoarthrosis of the right knee, indicated for a total knee arthroplasty. Considering the extent of previous procedures, which had significantly compromised the bone quality of the femur and therefore increased the risk of a refracture after an eventual hardware removal, we decided to retain the LCP plate. We concluded that the optimal solution would be the use of a computer-navigated total knee arthroplasty. This procedure obviated the need for intramedullary guiding, while ensuring optimal joint alignment. No postoperative complications emerged.

Toxocariasis as a Rare Parasitic Complication of a Transthoracic Spine Surgery Procedure.

Human toxocariasis is a helminthozoonosis caused by the migration of Toxocara species larvae through an organism. The infection in humans is transmitted either by direct ingestion of the eggs of the parasite, or by consuming undercooked meat infested with Toxocara larvae. This parasitosis can be found worldwide, but there are significant differences in seroprevalence in different areas, depending mainly on hot climate conditions and on low social status. However, the literature estimates of seroprevalence are inconsistent. Infected patients commonly present a range of symptoms, e.g., abdominal pain, decreased appetite, restlessness, fever, and coughing. This manuscript presents a case report of a polytraumatic patient who underwent a two-phase spinal procedure for a thoracolumbar fracture. After the second procedure, which was a vertebral body replacement via thoracotomy, the patient developed a pathologic pleural effusion. A microscopic cytology examination of this effusion revealed the presence of Toxocara species larvae. Although the patient presented no specific clinical symptoms, and the serological exams (Enzyme-linked immunosorbent assay (ELISA), Western blot) were negative, the microscopic evaluation enabled a timely diagnosis. The patient was successfully treated with albendazole, with no permanent sequelae of the infection.

Rare Case of Traumatic Anterior Knee Dislocation of Total Knee Arthroplasty With a Serious Neurovascular Injury.

Traumatic anterior dislocation of a total knee arthroplasty (TKA) is an extremely rare occurrence. There are only a few known cases of this type of dislocation which discuss the high risk of a neurovascular complication. This article describes a traumatic anterior dislocation of the TKA with a severe vascular lesion in a 75-year-old severely comorbid patient. Further complications led to the development of a compartment syndrome. Despite the repeated effort in performing a well-functioning anastomosis of the popliteal artery tear by the vascular surgeon, reperfusion of the lower extremity was not effective. Furthermore, multiorgan system failure due to the reperfusion syndrome evolved. This led to an above-knee amputation as a lifesaving procedure. Despite thorough intensive care therapy, the patient did not survive this complication. Presently there are no reported cases with such severe complications after the luxation of a previously well-functioning TKA leading to the death of the patient.

Cotargeting of BCL2 with Venetoclax and MCL1 with S63845 Is Synthetically Lethal In Vivo in Relapsed Mantle Cell Lymphoma.

PURPOSE: Mantle cell lymphoma (MCL) is an aggressive subtype of B-cell non-Hodgkin lymphomas characterized by (over)expression of BCL2. A BCL2-targeting drug, venetoclax, has promising anticancer activity in MCL. We analyzed molecular mechanisms of venetoclax resistance in MCL cells and tested strategies to overcome it. EXPERIMENTAL DESIGN: We confirmed key roles of proapoptotic proteins BIM and NOXA in mediating venetoclax-induced cell death in MCL. Both BIM and NOXA are, however, differentially expressed in cell lines compared with primary cells. First, NOXA protein is significantly overexpressed in most MCL cell lines. Second, deletions of BIM gene harbored by three commonly used MCL cell lines (JEKO-1, MINO, and Z138) were not found by array comparative genomic hybridization using a validation set of 24 primary MCL samples. RESULTS: We demonstrated that MCL1 and NOXA play important roles in mediating resistance to venetoclax. Consequently, we tested an experimental treatment strategy based on cotargeting BCL2 with venetoclax and MCL1 with a highly specific small-molecule MCL1 inhibitor S63845. The combination of venetoclax and S63845 demonstrated synthetic lethality in vivo on a panel of five patient-derived xenografts established from patients with relapsed MCL with adverse cytogenetics. CONCLUSIONS: Our data strongly support investigation of venetoclax in combination with S63845 as an innovative treatment strategy for chemoresistant MCL patients with adverse cytogenetics in the clinical grounds.

Mantle cell lymphoma-variant Richter syndrome: Detailed molecular-cytogenetic and backtracking analysis reveals slow evolution of a pre-MCL clone in parallel with CLL over several years.

Richter syndrome represents the transformation of the chronic lymphocytic leukemia (CLL) into an aggressive lymphoma, most frequently the diffuse large B-cell lymphoma (DLBCL). In this report we describe a patient with CLL, who developed a clonally-related pleomorphic highly-aggressive mantle cell lymphoma (MCL) after five cycles of a fludarabine-based second-line therapy for the first relapse of CLL. Molecular cytogenetic methods together with whole-exome sequencing revealed numerous gene alterations restricted to the MCL clone (apart from the canonical t(11;14)(q13;q32) translocation) including gain of one copy of ATM gene or emergence of TP53, CREBBP, NUP214, FUBP1 and SF3B1 gene mutations. Similarly, gene expression analysis revealed vast differences between the MCL and CLL transcriptome, including overexpression of cyclin D1, downregulation of cyclins D2 and D3, or downregulation of IL4R in the MCL clone. Backtracking analysis using quantitative PCR specifically detecting an MCL-restricted focal deletion of TP53 revealed that the pre-MCL clone appeared in the bone marrow and peripheral blood of the patient approximately 4 years before the clinical manifestation of MCL. Both molecular cytogenetic and sequencing data support the hypothesis of a slow development of the pre-MCL clone in parallel to CLL over several years, and thereby exclude the possibility that the transformation event occurred at the stage of the CLL relapse clone by mere t(11;14)(q13;q32) acquisition.

Targeting of BCL2 Family Proteins with ABT-199 and Homoharringtonine Reveals BCL2- and MCL1-Dependent Subgroups of Diffuse Large B-Cell Lymphoma.

PURPOSE: To investigate the roles of BCL2, MCL1, and BCL-XL in the survival of diffuse large B-cell lymphoma (DLBCL). EXPERIMENTAL DESIGNS: Immunohistochemical analysis of 105 primary DLBCL samples, and Western blot analysis of 18 DLBCL cell lines for the expression of BCL2, MCL1, and BCL-XL. Pharmacologic targeting of BCL2, MCL1, and BCL-XL with ABT-199, homoharringtonine (HHT), and ABT-737. Analysis of DLBCL clones with manipulated expressions of BCL2, MCL1, and BCL-XL. Immunoprecipitation of MCL1 complexes in selected DLBCL cell lines. Experimental therapy aimed at inhibition of BCL2 and MCL1 using ABT-199 and HHT, single agent, or in combination, in vitro and in vivo on primary cell-based murine xenograft models of DLBCL. RESULTS: By the pharmacologic targeting of BCL2, MCL1, and BCL-XL, we demonstrated that DLBCL can be divided into BCL2-dependent and MCL1-dependent subgroups with a less pronounced role left for BCL-XL. Derived DLBCL clones with manipulated expressions of BCL2, MCL1, and BCL-XL, as well as the immunoprecipitation experiments, which analyzed MCL1 protein complexes, confirmed these findings at the molecular level. We demonstrated that concurrent inhibition of BCL2 and MCL1 with ABT-199 and HHT induced significant synthetic lethality in most BCL2-expressing DLBCL cell lines. The marked cytotoxic synergy between ABT-199 and HHT was also confirmed in vivo using primary cell-based murine xenograft models of DLBCL. CONCLUSIONS: As homoharringtonine is a clinically approved antileukemia drug, and ABT-199 is in advanced phases of diverse clinical trials, our data might have direct implications for novel concepts of early clinical trials in patients with aggressive DLBCL.

Thermodynamics Study of Solvent Adsorption on Octadecyl-Modified Silica.

Elution and solvation processes in liquid chromatography may be controlled by temperature changes. In the case of solvent adsorption, the temperature influences the amount of adsorbed solvent as well as the enthalpy and entropy of the solvation process. In this work, the thermodynamic parameters of organic solvents used as organic modifiers in the reversed-phase high-performance liquid chromatography elution process were determined. The changes of enthalpy and entropy in a series of chemically bonded stationary phases were measured to determine the effects of the temperature and surface coverage density of octadecyl ligands on the thermodynamic parameters of the solvation. For both the enthalpy and entropy a parabolic trend was observed with the minimum for medium surface coverage. The correlation of solvent adsorption values with the enthalpy of solvation was also investigated. The highest influence of the temperature on solvation process was observed for stationary phases with high surface coverage.

Determination of the polyphenolic content of a Capsicum annuum L. extract by liquid chromatography coupled to photodiode array and mass spectrometry detection and evaluation of its biological activity.

The present study was aimed to investigate the polyphenolic profile of a pepper (Capsicum annuum L.) extract from Algeria and evaluate its biological activity. The total polyphenol content of the extract was determined as 1.373 mg of gallic acid equivalents (±0.0046), whereas the flavonoids were determined as 0.098 mg of quercetin (±0.0015). The determination of the complete polyphenolic profile of the extract was achieved by liquid chromatography with an RP-amide column in combination with photodiode array and mass spectrometry detection through an electrospray ionization interface. A total of 18 compounds were identified, of which five were reported for the first time in the sample tested. Quercetin rhamnoside was the most abundant compound (82.6 µg/g of fresh pepper) followed by quercetin glucoside (19.86 µg/g). The antioxidant activity and antimicrobial effects were also determined. For the antimicrobial tests assessed against Gram-positive and Gram-negative bacteria, kaempferol showed the strongest inhibitory effect followed by quercetin and caffeic acids. In the study of the cytotoxicity of the extract, the cancer cells (U937) were more affected than the normal cells (peripheral blood mononucleated cells), with more than 62% inhibition at the highest concentration.

Adsorption of water from aqueous acetonitrile on silica-based stationary phases in aqueous normal-phase liquid chromatography.

Excess adsorption of water from aqueous acetonitrile mobile phases was investigated on 16 stationary phases using the frontal analysis method and coulometric Karl-Fischer titration. The stationary phases include silica gel and silica-bonded phases with different polarities, octadecyl and cholesterol, phenyl, nitrile, pentafluorophenylpropyl, diol and zwitterionic sulfobetaine and phosphorylcholine ligands bonded on silica, hybrid organic-silica and hydrosilated matrices. Both fully porous and core-shell column types were included. Preferential uptake of water by the columns can be described by Langmuir isotherms. Even though a diffuse rather than a compact adsorbed discrete layer of water on the adsorbent surface can be formed because of the unlimited miscibility of water with acetonitrile, for convenience, the preferentially adsorbed water was expressed in terms of a hypothetical monomolecular water layer equivalent in the inner pores. The uptake of water strongly depends on the polarity and type of the column. Less than one monomolecular water layer equivalent was adsorbed on moderate polar silica hydride-based stationary phases, Ascentis Express F5 and Ascentis Express CN column at the saturation capacity, while on more polar stationary phases, several water layer equivalents were up-taken from the mobile phase. The strongest affinity to water was observed on the ZIC cHILIC stationary phases, where more than nine water layer equivalents were adsorbed onto its surface at its saturation capacity. Columns with bonded hydroxyl and diol ligands show stronger water adsorption in comparison to bare silica. Columns based on hydrosilated silica generally show significantly decreased water uptake in comparison to stationary phases bonded on ordinary silica. Significant correlations were found between the water uptake and the separation selectivity for compounds with strong polarity differences.

[A complex diagnostic approach in lymphomas: practical aspect in short case reports]. / Komplexní prístup v diagnostice lymfomu v praktických príkladech.

Complex laboratory investigation is necessary for the diagnosis and relevant classification of lymphomas. The classical histopathological morphology and cytology investigation is essential, but further investigations such as immunohistochemistry and fluorescence in situ hybridization are necessary. It is also important to employ flow cytometry as a method of investigation running synchronously or preceding the histopathological approach. Last but not least, the investigation of nucleic acids in lymphoma by molecular approaches is necessary and has become an everyday practice. Communication between pathologists and clinical colleagues (oncologists, hematologists, internal medicine specialists and radiologists) is very important. We demonstrate the necessity of a complex diagnostic approach to lymphomas and an appropriate interpretation of all laboratory investigations giving examples of eight patients with various types of lymphomas. In some cases, it is impossible to properly diagnose a lymphoma without molecular investigation. Occasionally, the results of the molecular investigation may be misleading and/or may be inaccurately interpreted, leading to an incorrect conclusion. For that reason, it is very important to incorporate all specialized laboratories and their teams under one roof (preferably that of pathology departments), enabling tight and daily cooperation between the specialists. This is the way to reach a precise diagnosis in a majority of cases, as well as how to comply with clinical expectations of properly classified lymphomas for a targeted therapy of patients.

Comparison of four cholesterol-based stationary phases for the separation of steroid hormones.

The chromatographic behavior of steroid hormones on four cholesterol-bonded stationary phases with different structures in binary methanol/water mobile phases was studied. Of the stationary phases tested, the commercially available stationary phases Cogent UDC cholesterol™ and COSMOSIL cholester™ provided better separations of steroid hormones in comparison to homemade aminocholesterol and diaminocholesterol stationary phases. The results show that the temperature has a significant influence on the retention and selectivity for steroid hormones separation. The temperature increase may cause changes in the elution order. From the dependences of the retention (ln k) on temperature (1/T), the standard partial molar enthalpy and standard partial molar entropy were calculated and their enthalpic and entropic contributions to the retention were compared. The enthalpic effects principally control the retention mechanism.

Comparison of nonaqueous hydrophilic interaction chromatography with aqueous normal-phase chromatography on hydrosilated silica-based stationary phases.

We investigated the retention behavior of phenolic acids in nonaqueous normal-phase (NP) LC with buffered methanol/acetonitrile mobile phases on hydrosilated silica-based stationary phases. The silica hydride, Diamond hydride, Bidentate C18, and Cholesterol columns showed a higher retention of phenolic acids in the nonaqueous mobile phases than in aqueous NP mobile phases. There are some selectivity differences between the aqueous and nonaqueous mobile phases, but generally the resolution and selectivity are better in the aqueous systems. The retention of the phenolic acids tested decreased with increasing concentration of methanol in the mobile phase, up to 20% v/v methanol. At increased temperatures, the retention factors and peak widths decrease in both NP modes, showing linear ln k versus 1/T plots, due to a single retention mechanism over the temperature range from 25°C up to the column stability limit, however, the best separations are achieved at low temperatures. The enthalpic and entropic contributions to the retention were determined, and the differences between the aqueous and nonaqueous modes are possibly due to the adsorbed water layer.

Gradient elution in aqueous normal-phase liquid chromatography on hydrosilated silica-based stationary phases.

The possibility of applying a theoretical model in the prediction of the retention of phenolic acids on hydrosilated silica, in aqueous normal phase mode was studied. The actual gradient of the aqueous component in acetonitrile may fluctuate from the pre-set program, as even the gradient-grade acetonitrile contains some water. Hence, the actual concentration of water during the gradient run is higher than pre-set by the gradient program, which leads to lower than expected sample retention. Furthermore, the actual gradient profile may be affected by an increase in water uptake on a polar column during the gradient run. These effects were investigated using the using frontal analysis method and Karl-Fischer titration, for the determination of water in the initial mobile phase, and in the column effluent. Preferential adsorption of water on the Silica hydride, Diamond hydride, UDC Cholesterol, Bidentate C18, and Phenyl hydride columns can be described by Langmuir isotherms. At the column saturation capacity, less than one monomolecular water layer is adsorbed, with a further decrease in coverage density for modified materials. Parameters of semi-logarithmic and logarithmic model equations, describing the dependence of retention factor on the concentration of water, were determined under isocratic conditions. These parameters and linear gradient profiles corrected for the actual water concentrations were used in calculation of gradient retention data. The corrections for the actual water concentration greatly improved the agreement between the experiment and the predicted gradient elution volumes. Generally, the semi-logarithmic model provides slightly better prediction of the gradient data, with respect to the logarithmic retention model.

The effect of temperature and mobile phase composition on separation mechanism of flavonoid compounds on hydrosilated silica-based columns.

We investigated the effects of mobile phase composition on the retention of flavones on four different hydrosilated C silica-based columns in buffered aqueous acetonitrile. Cogent UDC cholesterol™ and Cogent bidentate C18™ columns show significant dual reversed-phase/normal-phase retention behavior, while Cogent Diamond hydride™ and Cogent Silica hydride™ columns show negligible retention in the reversed-phase mode. The effect of the aqueous acetate buffer concentration on retention factors of flavones over the full mobile phase composition range, including both aqueous normal-phase (ANP) and reversed-phase mechanisms, can be described by a four-parameter equation for dual-retention mechanism. At increasing temperature, the retention factors and peak widths decrease both in the aqueous normal phase and in the reversed phase mobile phase range. In agreement with van't Hoff model, linear lnk versus 1/T plots were observed, showing a single retention mechanism in the highly organic normal-phase and in highly aqueous reversed-phase mobile phase ranges. From among the stationary phases tested, Cogent UDC cholesterol™ column has high temperature stability (up to 100 °C) and provides most selective and efficient separations of flavones both in the ANP and in the RP modes with almost reversed elution order.

The influence of the organic modifier in hydro-organic mobile phase on separation selectivity of steroid hormones separation using cholesterol-bonded stationary phases.

Chromatographic properties of four cholesterol bonded phases with different structures were studied. The columns used were packed with a stationary phase containing a cholesterol molecule attached to the silica surface using different types of linkage molecules. Columns were compared according to the retention and separation selectivity of steroid hormones. The measurements were done using binary hydro-organic mobile phases with methanol, ethanol and acetonitrile as an organic modifier. The presented results show that the coverage density of the bonded ligands and the type of organic modifier strongly influence the retention mechanism and separation selectivity of steroid hormones on cholesterol-containing adsorbents.

Hydrosilated silica-based columns: the effects of mobile phase and temperature on dual hydrophilic-reversed-phase separation mechanism of phenolic acids.

The effects of mobile phase composition and of temperature on the retention behavior of phenolic acids were studied on 4 hydrosilated (type C silica) based columns in buffered aqueous acetonitrile, both in the aqueous normal phase (HILIC) and in the reversed-phase mobile phase range. The UDC cholesterol and the C18 bidentate columns show significant reversed phase and normal-phase retention mechanisms, whereas very weak retention in the reversed-phase mode was observed on the silica hydride and the Diamond hydride columns. The concentration effects of the aqueous acetate buffer over the full mobile phase (HILIC and RP) composition range can be described by a simple four-parameter equation. At increasing temperature, the retention times and peak widths decrease both in the aqueous normal phase and in the reversed phase mobile phase range. Linear van't Hoff log k versus 1/T plots were observed, indicating a single retention mechanism predominating in the highly organic (HILIC), like in highly aqueous (RP) mobile phase ranges. Besides the type of the stationary phase, the separation selectivity of phenolic acids strongly depends on temperature and on the mobile phase composition. From among the 4 hydrosilated columns compared in this work, the UDC cholesterol column has high temperature stability (up to 100 °C) and is most suitable for selective and efficient separations of phenolic acids both in the HILIC and in the RP modes.

Screen-printed carbon electrodes modified by rhodium dioxide and glucose dehydrogenase.

The described glucose biosensor is based on a screen-printed carbon electrode (SPCE) modified by rhodium dioxide, which functions as a mediator. The electrode is further modified by the enzyme glucose dehydrogenase, which is immobilized on the electrode's surface through electropolymerization with m-phenylenediamine. The enzyme biosensor was optimized and tested in model glucose samples. The biosensor showed a linear range of 500-5000 mg L(-1) of glucose with a detection limit of 210 mg L(-1) (established as 3σ) and response time of 39 s. When compared with similar glucose biosensors based on glucose oxidase, the main advantage is that neither ascorbic and uric acids nor paracetamol interfere measurements with this biosensor at selected potentials.