Radim Lipina

Prevalence of Propionibacterium acnes in Intervertebral Discs of Patients Undergoing Lumbar Microdiscectomy: A Prospective Cross-Sectional Study

Background The relationship between intervertebral disc degeneration and chronic infection by Propionibacterium acnes is controversial with contradictory evidence available in the literature. Previous studies investigating these relationships were under-powered and fraught with methodical differences; moreover, they have not taken into consideration P. acnes’ ability to form biofilms or attempted to quantitate the bioburden with regard to determining bacterial counts/genome equivalents as criteria to differentiate true infection from contamination. The aim of this prospective cross-sectional study was to determine the prevalence of P. acnes in patients undergoing lumbar disc microdiscectomy. Methods and Findings The sample consisted of 290 adult patients undergoing lumbar microdiscectomy for symptomatic lumbar disc herniation. An intraoperative biopsy and pre-operative clinical data were taken in all cases. One biopsy fragment was homogenized and used for quantitative anaerobic culture and a second was frozen and used for real-time PCR-based quantification of P. acnes genomes. P. acnes was identified in 115 cases (40%), coagulase-negative staphylococci in 31 cases (11%) and alpha-hemolytic streptococci in 8 cases (3%). P. acnes counts ranged from 100 to 9000 CFU/ml with a median of 400 CFU/ml. The prevalence of intervertebral discs with abundant P. acnes (≥ 1x103 CFU/ml) was 11% (39 cases). There was significant correlation between the bacterial counts obtained by culture and the number of P. acnes genomes detected by real-time PCR (r = 0.4363, p<0.0001). Conclusions In a large series of patients, the prevalence of discs with abundant P. acnes was 11%. We believe, disc tissue homogenization releases P. acnes from the biofilm so that they can then potentially be cultured, reducing the rate of false-negative cultures. Further, quantification study revealing significant bioburden based on both culture and real-time PCR minimize the likelihood that observed findings are due to contamination and supports the hypothesis P. acnes acts as a pathogen in these cases of degenerative disc disease.

Propionibacterium acnes biofilm is present in intervertebral discs of patients undergoing microdiscectomy.

Background In previous studies, Propionibacterium acnes was cultured from intervertebral disc tissue of ~25% of patients undergoing microdiscectomy, suggesting a possible link between chronic bacterial infection and disc degeneration. However, given the prominence of P. acnes as a skin commensal, such analyses often struggled to exclude the alternate possibility that these organisms represent perioperative microbiologic contamination. This investigation seeks to validate P. acnes prevalence in resected disc cultures, while providing microscopic evidence of P. acnes biofilm in the intervertebral discs. Methods Specimens from 368 patients undergoing microdiscectomy for disc herniation were divided into several fragments, one being homogenized, subjected to quantitative anaerobic culture, and assessed for bacterial growth, and a second fragment frozen for additional analyses. Colonies were identified by MALDI-TOF mass spectrometry and P. acnes phylotyping was conducted by multiplex PCR. For a sub-set of specimens, bacteria localization within the disc was assessed by microscopy using confocal laser scanning and FISH. Results Bacteria were cultured from 162 discs (44%), including 119 cases (32.3%) with P. acnes. In 89 cases, P. acnes was cultured exclusively; in 30 cases, it was isolated in combination with other bacteria (primarily coagulase-negative Staphylococcus spp.) Among positive specimens, the median P. acnes bacterial burden was 350 CFU/g (12 - ~20,000 CFU/g). Thirty-eight P. acnes isolates were subjected to molecular sub-typing, identifying 4 of 6 defined phylogroups: IA1, IB, IC, and II. Eight culture-positive specimens were evaluated by fluorescence microscopy and revealed P. acnes in situ. Notably, these bacteria demonstrated a biofilm distribution within the disc matrix. P. acnes bacteria were more prevalent in males than females (39% vs. 23%, p = 0.0013). Conclusions This study confirms that P. acnes is prevalent in herniated disc tissue. Moreover, it provides the first visual evidence of P. acnes biofilms within such specimens, consistent with infection rather than microbiologic contamination.

Endoscopic third ventriculostomy in previously shunted children

Endoscopic third ventriculostomy (ETV) is a routine and safe procedure for therapy of obstructive hydrocephalus. The aim of our study is to evaluate ETV success rate in therapy of obstructive hydrocephalus in pediatric patients formerly treated by ventriculoperitoneal (V-P) shunt implantation. From 2001 till 2011, ETV was performed in 42 patients with former V-P drainage implantation. In all patients, the obstruction in aqueduct or outflow parts of the fourth ventricle was proved by MRI. During the surgery, V-P shunt was clipped and ETV was performed. In case of favourable clinical state and MRI functional stoma, the V-P shunt has been removed 3 months after ETV. These patients with V-P shunt possible removing were evaluated as successful. In our group of 42 patients we were successful in 29 patients (69%). There were two serious complications (4.7%)—one patient died 2.5 years and one patient died 1 year after surgery in consequence of delayed ETV failure. ETV is the method of choice in obstructive hydrocephalus even in patients with former V-P shunt implantation. In case of acute or scheduled V-P shunt surgical revision, MRI is feasible, and if ventricular system obstruction is diagnosed, the hydrocephalus may be solved endoscopically.

Nationwide study of decompressive surgery for malignant supratentorial infarction in the Czech Republic: utilization and outcome predictors. Clinical article.

OBJECT Decompressive surgery within 48 hours in patients younger than 60 years of age reduces mortality and morbidity from malignant supratentorial infarction. The goal of this study was to characterize the utilization of decompressive surgery in the Czech Republic in 2006. METHODS This nationwide study was undertaken from September to December 2007 using a questionnaire sent to all neurosurgery departments in the Czech Republic. Diagnosis of brain infarction and decompressive surgery was based on discharge codes. Patient data were retrieved from hospital charts. Favorable outcome was defined as a modified Rankin scale score ≤4 on the day of discharge from the hospital. RESULTS Data were obtained from 15 of the 16 neurosurgery departments in the Czech Republic (94%) and from 39 patients (11 female [28%]). The average patient age was 52 +/-14 years (11 patients > 60), median time to surgery was 48 hours (interquartile range [IQR] 26-67 hours; 15 patients > 48 hours), median National Institutes of Health Stroke Scale score was 22 (IQR 16-30), median infarct volume was 341 cm³ (IQR 243-375 cm³), mean shift from the midline was 9.9 +/- 4.1 mm, median duration of hospitalization was 19 days (IQR 13-30 days), and mean bone flap surface area was 75 cm² (IQR 70-97 cm²). A favorable outcome was achieved in 19 patients (49%). The median number of procedures per site in 2006 was 1.5 (range 0-13 procedures). Five sites (31%) serving one-third of the entire population did not perform any decompressive surgery. No variable was a significant predictor of outcome in a multiple regression model. CONCLUSIONS In 2006 decompressive surgery was underutilized and occurred late in the clinical course in the Czech Republic. Revision of national guidelines is necessary to incorporate the latest data and ensure that the patients who can benefit most receive treatment.

Long Non-Coding RNAs in Gliomas: From Molecular Pathology to Diagnostic Biomarkers and Therapeutic Targets

Gliomas are the most common malignancies of the central nervous system. Because of tumor localization and the biological behavior of tumor cells, gliomas are characterized by very poor prognosis. Despite significant efforts that have gone into glioma research in recent years, the therapeutic efficacy of available treatment options is still limited, and only a few clinically usable diagnostic biomarkers are available. More and more studies suggest non-coding RNAs to be promising diagnostic biomarkers and therapeutic targets in many cancers, including gliomas. One of the largest groups of these molecules is long non-coding RNAs (lncRNAs). LncRNAs show promising potential because of their unique tissue expression patterns and regulatory functions in cancer cells. Understanding the role of lncRNAs in gliomas may lead to discovery of the novel molecular mechanisms behind glioma biological features. It may also enable development of new solutions to overcome the greatest obstacles in therapy of glioma patients. In this review, we summarize the current knowledge about lncRNAs and their involvement in the molecular pathology of gliomas. A conclusion follows that these RNAs show great potential to serve as powerful diagnostic, prognostic, and predictive biomarkers as well as therapeutic targets.

Factors That Predict the Growth of Residual Nonfunctional Pituitary Adenomas: Correlations between Relapse and Cell Cycle Markers

Introduction Nonfunctional pituitary adenomas are treated surgically, and even partial resection can improve or eliminate clinical symptoms. Notably, progression requires further intervention, which presents an increased risk, especially in older patients. This study investigated whether the histopathological characteristics of nonfunctional adenomas could predict recurrence. Materials and Methods Data were obtained retrospectively from 30 patients who underwent surgery for the partial resection of pituitary adenomas. Remnant tumor growth was observed in 17 patients, while the residual tumor was unchanged more than 7 years after surgery in 13 patients. Statistical analysis was performed to investigate correlations between remnant tumor progression and tumor histopathological findings, including protein expression of p21, p27, p53, and Ki-67. Results and Discussion Remnant tumors that demonstrated regrowth showed significantly higher protein expression of p21 and Ki-67. Expression of the p53 tumor suppressor was also higher in this group, but the difference was at the limit of statistical significance. Conclusion Tumors with high expression of p21 and p53 and with a high Ki-67 index were more likely to show residual pituitary adenoma progression. Such cases should undergo frequent radiological examination and timely reoperation, and radiosurgery should be considered.

Abstract 3445: ZFAS1 is upregulated in GBM tissue and affects viability and migration of GBM cells in vitro

Introduction: Glioblastoma multiforme (GBM) is the most frequent primary brain tumor of astrocytic origin characterized by very poor prognosis. Despite conventional therapeutic protocol the prognosis of GBM patients is very poor with median of overall survival ranging between 12 and 15 months from diagnosis. Therefore, many financial charges and lot of effort is spent in research of new therapeutic approaches that could prolong the survival of GBM patients. Long non-coding RNAs (lncRNAs) are a relatively new class of noncoding gene regulators playing critical roles in tumor biology, including GBM. From this perspective, lncRNAs seem to be promising therapeutic targets in GBM patients. Material and Methods: We performed next-generation sequencing analysis of fresh-frozen histopatologically confirmed 45 GBM tissues and 5 non-tumor brain tissues obtained from non-dominant anterior temporal cortexes resected during surgery for intractable epilepsy. Informed consent approved by the local Ethical Commission was obtained from each patient before the treatment. rRNA depletion and cDNA library preparation were performed with GeneRead rRNA Depletion Kit (Qiagen) and NEXTflex Rapid Directional qRNA-Seq Kit (Bioo Scientific), respectively. Sequencing was held using NextSeq 500 High Output Kit and NextSeq 500 instrument (both Illumina). Statistical analysis evaluated 24 087 protein-coding and 8 414 non-coding RNAs and their sequential variants with non-zerou RPKM (Reads Per Kilobase of transcript per Million mapped reads) at least in one sample. We used CLC genomic workbench for the alignment and target counts. Targeted regulation of ZFAS1 level have been carried out by the transient transfection of specific siRNA in GBM stable cell lines (A172, T98G, U87MG, U251). Viability and migration were analyzed in vitro using MTT and scratch wound healing assay, respectively. Results: Statistical analysis has revealed 274 (P Note: This abstract was not presented at the meeting. Citation Format: Jiri Sana, Marek Vecera, Romana Butova, Jaroslav Juracek, Tana Machackova, Parwez Ahmad, Natalia Anna Gablo, Kamila Souckova, Leos Kren, Radim Lipina, Martin Smrcka, Ondrej Slaby. ZFAS1 is upregulated in GBM tissue and affects viability and migration of GBM cells in vitro [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3445. doi:10.1158/1538-7445.AM2017-3445