ISSLS PRIZE in Clinical Science 2023: comparison of degenerative MRI features of the intervertebral disc between those with and without chronic low back pain. An exploratory study of two large female populations using automated annotation.

OBJECTIVES: The relationship of degeneration to symptoms has been questioned. MRI detects apparently similar disc degeneration and degenerative changes in subjects both with and without back pain. We aimed to overcome these problems by re-annotating MRIs from asymptomatic and symptomatics groups onto the same grading system. METHODS: We analysed disc degeneration in pre-existing large MRI datasets. Their MRIs were all originally annotated on different scales. We re-annotated all MRIs independent of their initial grading system, using a verified, rapid automated MRI annotation system (SpineNet) which reported degeneration on the Pfirrmann (1-5) scale, and other degenerative features (herniation, endplate defects, marrow signs, spinal stenosis) as binary present/absent. We compared prevalence of degenerative features between symptomatics and asymptomatics. RESULTS: Pfirrmann degeneration grades in relation to age and spinal level were very similar for the two independent groups of symptomatics over all ages and spinal levels. Severe degenerative changes were significantly more prevalent in discs of symptomatics than asymptomatics in the caudal but not the rostral lumbar discs in subjects < 60 years. We found high co-existence of degenerative features in both populations. Degeneration was minimal in around 30% of symptomatics < 50 years. CONCLUSIONS: We confirmed age and disc level are significant in determining imaging differences between asymptomatic and symptomatic populations and should not be ignored. Automated analysis, by rapidly combining and comparing data from existing groups with MRIs and information on LBP, provides a way in which epidemiological and 'big data' analysis could be advanced without the expense of collecting new groups. LEVEL OF EVIDENCE I: Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding.

[Incidence, Diagnosis and Risk Factors for Fracture-Related Infection (FRI): 3-Year Experience of Level I Trauma Centre]. / Incidence a diagnostika infektu pri zlomenine (FRI) a rizikové faktory jeho vzniku: tríleté zkusenosti traumacentra I. stupne.

PURPOSE OF THE STUDY The study aims to determine the incidence of fracture-related infection (hereinafter referred to as the FRI) at a Level I trauma centre over a three-year period. It also aimed to determine the risk factors, to observe confirmatory and suggestive criteria in line with the applicable recommendations, and to evaluate the bacterial spectrum in a diagnosed FRI. MATERIAL AND METHODS It is a retrospective-prospective study carried out through studying the documentation. The study included all patients diagnosed with FRI and treated between 2019 and 2021, except for the patients with hand fractures since minor phalangeal fractures of the fingers were largely treated by the outpatient department, no osteosynthesis was performed in the operating room, and these patients were not followed up at our department. RESULTS The FRI incidence was 2.33% of all osteosyntheses performed at the Level 1 trauma centre in the period 2019-2021. The FRI was most often caused by pyogenic cocci agents and the FRI developed most frequently within 6 months after osteosynthesis. The site at risk was the lower limb region. The FRI incidence was most often indicated by suggestive clinical criteria (redness, secretion, pain) and radiological criteria (delayed healing, non-union). Overall, 42.19% of treated nonunions were later diagnosed as FRI. At the time of FRI diagnosis, the CRP values were normal in 21.7% of patients. DISCUSSION The FRI incidence rate in 2019-2021 was 2.33%, which corresponds with the values reported in other papers focusing on the incidence of infectious complications after osteosynthesis. Fang and Depypere reported 1-2% of infectious complications. The most common risk factors are open fractures, which account for 20.16% in our cohort. Ktistakis and Depypere describe the incidence of osteomyelitis in 30% of treated open fractures. In our cohort, the incidence of FRI was significantly higher in lower limb fractures. Bezstarosti, Wang and Pesch published similar results, with some deviations. The time from osteosynthesis to final FRI diagnosis varied from a few weeks to several years. In more than half of the patients the FRI developed within 6 months after performed osteosynthesis. Metsemakers and Fang refer to the very same trend. The CRP levels in the study population varied a lot. Xing-qi Zhao describes CRP as a less sensitive (sensitivity 65.6%) but more specific marker (specificity 75.4%). According to the available literature, the most common agents causing infectious complications of osteosynthesis are gram-positive cocci, S. aureus in particular. In our study, G+ pyogenic cocci were clearly the most commonly detected, which is consistent with the results of studies by Fang and Depypere, focused on the incidence of infectious complications. The most common FRI clinical manifestations included wound secretion, redness, swelling and pain. Furthermore, suggestive radiological criteria, especially delayed healing and non-union also indicated the FRI occurrence. According to Fang, the most common clinical manifestations of infectious complications include pain, swelling, redness and wound dehiscence. Fang reports that the most common radiologic findings are the periosteal reaction, loosening of the implant and delayed healing or non-union, which is consistent with our cohort. In the cohort of non-unions surgically treated at our department, FRI was subsequently confirmed in 42.19% of cases. CONCLUSIONS The incidence of FRI at Level 1 trauma centre was 2.33% of operated fractures in 2019-2021, with pyogenic cocci being the most common infectious agents. The FRI usually developed within 6 months after osteosynthesis. The typical site for the FRI development was the lower limb region, the ongoing FRI was indicated by suggestive clinical criteria (redness, secretion, pain) and radiological criteria (delayed healing and a non-union). Overall, 42.19% of treated non-unions were later diagnosed as FRI. Key words: fracture-related infection, FRI, suggestive criteria, confirmatory criteria, FRI diagnosis, microbial, microbiology spectrum, osteosynthesis, complications, non-union.

Suppression of Oxidative Stress and Proinflammatory Cytokines Is a Potential Therapeutic Action of Ficus lepicarpa B. (Moraceae) against Carbon Tetrachloride (CCl4)-Induced Hepatotoxicity in Rats.

Local tribes use the leaves of Ficus lepicarpa B. (Moraceae), a traditional Malaysian medicine, as a vegetable dish, a tonic, and to treat ailments including fever, jaundice and ringworm. The purpose of this study was to look into the possible therapeutic effects of F. lepicarpa leaf extract against carbon tetrachloride (CCl4)-induced liver damage in rats. The DPPH test was used to measure the antioxidant activity of plants. Gas chromatography-mass spectrometry was used for the phytochemical analysis (GCMS). Six groups of male Sprague-Dawley rats were subjected to the following treatment regimens: control group, CCl4 alone, F. lepicarpa 400 mg/kg alone, CCl4 + F. lepicarpa 100 mg/kg, CCl4 + F. lepicarpa 200 mg/kg and CCl4 + F. lepicarpa 400 mg/kg. The rats were euthanized after two weeks, and biomarkers of liver function and antioxidant enzyme status were assessed. To assess the extent of liver damage and fibrosis, histopathological and immunohistochemical examinations of liver tissue were undertaken. The total phenolic content and the total flavonoid content in methanol extract of F. lepicarpa leaves were 58.86 ± 0.04 mg GAE/g and 44.31 ± 0.10 mg CAE/g, respectively. F. lepicarpa's inhibitory concentration (IC50) for free radical scavenging activity was reported to be 3.73 mg/mL. In a dose-related manner, F. lepicarpa was effective in preventing an increase in serum ALT, serum AST and liver MDA. Histopathological alterations revealed that F. lepicarpa protects against the oxidative stress caused by CCl4. The immunohistochemistry results showed that proinflammatory cytokines (tumour necrosis factor-α, interleukin-6, prostaglandin E2) were suppressed. The antioxidative, anti-inflammatory, and free-radical scavenging activities of F. lepicarpa can be related to its hepatoprotective benefits.

GliPR1 knockdown by RNA interference exerts anti-glioma effects in vitro and in vivo.

INTRODUCTION: In human glioblastomas, glioma pathogenesis-related protein1 (GliPR1) is overexpressed and appears to be an oncoprotein. We investigated whether GliPR1 knockdown in glioma cells by RNA interference exerts anti-glioma effects. METHODS: Experiments used human glioblastoma cell lines transduced with GliPR1 shRNA (sh#301, sh#258). Transduction produced stringent doxycycline-dependent GliPR1 knockdown in clones (via lentiviral "all-in-one" TetOn-shRNA vector) or stable GliPR1 knockdown in polyclonal cells (via constitutive retroviral-shRNA vector). In vitro assessments included cellular proliferation and clonogenic survival. In vivo assessments in tumor-bearing nude mice included tumor growth and survival. RESULTS: Using doxycycline-dependent GliPR1 knockdown, shGliPR1-transduced U87-MG clones demonstrated reductions in cellular proliferation in the presence versus absence of doxycycline. Using stable GliPR1 knockdown, polyclonal shGliPR1-transduced U87-MG, A172, and U343-MG cells consistently showed decreased clonogenic survival and induced apoptosis (higher proportion of early apoptotic cells) compared to control shLuc-transduced cells. In tumor-bearing nude mice, using doxycycline-dependent GliPR1 knockdown, subcutaneous and cranial transplantation of the U87-MG clone 980-5 (transduced with GliPR1 sh#301) resulted in reduced subcutaneous tumor volume and cerebral tumor area in doxycycline-treated mice versus those left untreated. Using stable GliPR1 knockdown, nude mice cranially transplanted with polyclonal U87-MG cells transduced with GliPR1 sh#258 had significantly prolonged survival compared to mice cranially transplanted with control shLuc-transduced cells (41 versus 26 days; P < 0.001). CONCLUSION: GliPR1 knockdown in glioma cells decreased cellular proliferation, decreased clonogenic survival, and induced apoptosis in vitro, and reduced glioblastoma tumor growth and prolonged survival in vivo. These findings support that GliPR1 may have potential value as a therapeutic target.

Triggering receptor expressed on myeloid cells 1 and 2 in patients with chronic maxillary sinusitis.

PURPOSE: Chronic sinusitis can result from variable types of immune-mediated process, whose pathogenesis is not fully understood. Triggering receptors expressed on myeloid cells 1 and 2 (TREM-1, TREM-2) are involved in myeloid cell activation enabling these cells to fine-tune the inflammatory response, which may have an impact on subsequent adaptive immunity and may be the key factor in pathogenesis. The aim of the study was to analyse soluble TREM-1 and TREM-2 molecules in maxillary sinus lavage fluid and compare the defined subgroups selected from patients with chronic sinusitis with/without nasal polyps and allergy (asthma and allergic rhinitis). METHODS: The levels of soluble TREM-1 and TREM-2 were measured by Elisa test in a cohort of patients with chronic maxillary sinusitis (n=45). We compared subgroups of patients with nasal polyps (n=33) and allergy (n=25: inclusive of asthma (n=11) and allergic rhinitis (n=14)) with the control group of patients without nasal polyps (n=13), and without allergy (n=21). RESULTS: The study did not prove the difference between subgroups with and without nasal polyps. The levels of soluble TREM-1 did not differ significantly between patients with allergy (asthma and allergic rhinitis) and the control group without allergy (p=0.4804). The levels of soluble TREM-2 were significantly higher in patients with allergy (p=0.0028), asthma (p=0.0103) and allergic rhinitis (p=0.0137) as compared with the control group. CONCLUSION: Our results suggest the role of TREM-2­mediated activation of myeloid cells in chronic sinusitis accompanied by allergy, asthma, and allergic rhinitis (Tab. 6, Ref. 25).

Mathematical chromatography deciphers the molecular fingerprints of dissolved organic matter.

High-resolution mass spectrometry (HRMS) elucidates the molecular composition of dissolved organic matter (DOM) through the unequivocal assignment of molecular formulas. When HRMS is used as a detector coupled to high performance liquid chromatography (HPLC), the molecular fingerprints of DOM are further augmented. However, the identification of eluting compounds remains impossible when DOM chromatograms consist of unresolved humps. Here, we utilized the concept of mathematical chromatography to achieve information reduction and feature extraction. Parallel Factor Analysis (PARAFAC) was applied to a dataset describing the reverse-phase separation of DOM in headwater streams located in southeast Sweden. A dataset consisting of 1355 molecular formulas and 7178 mass spectra was reduced to five components that described 96.89% of the data. Each component summarized the distinct chromatographic elution of molecular formulas with different polarity. Component scores represented the abundance of the identified HPLC features in each sample. Using this chemometric approach allowed the identification of common patterns in HPLC-HRMS datasets by reducing thousands of mass spectra to only a few statistical components. Unlike in principal component analysis (PCA), components closely followed the analytical principles of HPLC-HRMS and therefore represented more realistic pools of DOM. This approach provides a wealth of new opportunities for unravelling the composition of complex mixtures in natural and engineered systems.

TREM-1 and TREM-2 Expression on CD14+ Cells in Bronchoalveolar Lavage Fluid in Pulmonary Sarcoidosis and Hypersensitivity Pneumonitis in the Context of T Cell Immune Response.

BACKGROUND: Sarcoidosis and hypersensitivity pneumonitis (HP) are immunologically mediated processes caused by hypersensitivity reaction accompanied by similar features including lymphocytic alveolitis and granuloma formation. Recent studies describe the role of TREM receptors in T cell activation, differentiation, and granuloma formation. Alveolar macrophages activation via TREM receptors may be the key factor mediating subsequent immune response. The aim of the study was to analyse TREM-1 and TREM-2 expression to identify further molecular mechanisms participating in the immunopathogenesis of sarcoidosis and HP. METHODS: Flow cytometry was performed to analyse TREM-1 and TREM-2 expression on CD14+ cells in bronchoalveolar lavage fluid from patients having sarcoidosis or HP and a control group. RESULTS: The study proved increased TREM-1 expression on alveolar macrophages in pulmonary sarcoidosis and diminished TREM-1 expression in HP-Sarcoidosis: median: 76.7; HP: median: 29.9; control: median: 53.3, (sarcoidosis versus HP: p < 0.001; sarcoidosis versus control: p < 0.05). TREM-2 expression was increased in both, sarcoidosis and HP-sarcoidosis: median: 34.79; HP: median: 36.00; control: median: 12.98, (sarcoidosis versus control: p < 0.05; HP versus control: p < 0.05). Correlation analysis showed negative correlation between TREM-1 and total number of CD8+ cytotoxic T cells. In sarcoidosis TREM-1 expression decreased with changes of HRCT image, decrease in CD4/CD8 ratio and decrease in DLCO. CONCLUSIONS: Differences in TREM receptor expression in sarcoidosis (increase in TREM-1 and TREM-2) and HP (increase in TREM-2) and correlation analysis suggests that activation via TREM may participate in typical immunological characteristics of sarcoidosis and HP.

Comparison of hair manifestations in cardio-facio-cutaneous and Costello syndromes highlights the influence of the RAS pathway on hair growth.

BACKGROUND: Abnormal hair growth is a defining feature of RASopathies, syndromes caused by germline mutations in the RAS pathway. However, detailed hair manifestations and the mechanisms of altered hair growth in RASopathies are poorly delineated. OBJECTIVES: To identify distinguishing clinical features and investigate how the RAS pathway influences hair growth by performing a systematic and detailed side-by-side comparison of hair manifestations in cardio-facio-cutaneous syndrome (CFCS) and Costello syndrome (CS), two RASopathies caused by mutations in the downstream and upstream elements of the RAS pathway, respectively. METHODS: Sixteen individuals with CFCS and 23 individuals with CS were enrolled. Mutation data were recorded. Scalp hair, eyebrows and eyelashes of individuals with CFCS or CS were examined for texture, colour, density and morphology. Scalp hairs were examined by light microscopy. RESULTS: While both syndromes displayed abnormal hair, striking differences were observed, including darker and thicker scalp hair and sparse eyebrows and eyelashes in CFCS. By contrast, synophrys, trichomegaly and abnormalities of the scalp hair shafts were observed in CS. Possible correlation with straight hair and genotype was observed in CS. CONCLUSION: The results emphasize the role of the RAS pathway in hair growth, improve accuracy of clinical diagnosis of CFCS and CS and provide a foundation for identification of therapeutic targets.

[Minimally Invasive Cancellous Bone Graft Harvesting in Trauma Indication - Clinical Part of the Study]. / Miniinvazivní odber spongiózních stepu v traumatologické indikaci ­ klinická cást studie.

PURPOSE OF THE STUDY The clinical prospective study presents the results of minimally invasive harvesting of cancellous bone tissue in trauma indications. We focused on evaluating the clinical outcomes of this technique, particularly on the amount of cancellous bone harvested, the effectiveness of its use and complications. The pain in the bone graft harvest site is evaluated and compared with the pain after a standard harvest from the iliac crest. MATERIAL AND METHODS All the patients aged 18-90 years, in whom cancellous bone was harvested by minimally invasive technique using a bone cutter were included prospectively in the study. It was used to fill the defect in treating a fracture or in surgical treatment of non-union. The patients, in whom the grafts harvested in this manner were combined with another substitute, were not included in the study. Thus, 57 adult patients (40 men, 17 women) were included in the group in the period from March 2012 to March 2016. 37 patients, i.e. 65% of the total number of 57 patients, arrived for the evaluation of the clinical outcome. The minimally invasive graft harvesting was performed using the Aesculap® cutters. The graft was harvested either from the skeleton directly in the area of surgical wound or by a mini incision above the harvest site in the area under surgical drapes. The diameter of the cutter was selected based on the planned necessary number of grafts and with account taken of the harvest site. There were 6 harvest sites selected - proximal humerus, proximal ulna, iliac crest, greater trochanter of femur, distal femur and proximal tibia. The age and gender of patients, harvest site, type of the used cutter and the total number of harvested grafts were recorded in the study. The patients underwent a clinical follow-up at 6 weeks, 3 months, 6 months and 1 year postoperatively. The healing of the fracture or non-union was assessed on radiographs and in case of any doubt a CT scan was indicated. The pain at the graft harvest site was quantified with the use of the VAS score. A possible correlation between the age and the harvest site pain was explored by means of the Pearson s correlation coefficient. RESULTS In surgical management of fractures, 10.98 cm³ of bone marrow (σ 5.32) was harvested on average, in non-unions it was 10.85 cm³ (σ 5.52). With the above described technique, the mean healing time of lower extremity fractures was 26 weeks, in upper extremity it was 22 weeks. The non-unions of lower extremity and upper extremity healed after 28 weeks and 19 weeks, respectively. The average pain at the harvest site was 4.08 (σ 2.21, p ˂ 0.001). By calculating the Pearson's correlation coefficient it was confirmed that there is no correlation between the age and pain VAS score at the harvest site (r = -0.05). No early complications at the graft harvest site were observed in our group of patients. DISCUSSION On average, 10.98 cm³ of bone marrow was harvested in treated fractures, which in comparison to standard harvests from the iliac crest offers sufficient amount of tissue to treat complicated fractures and non-unions. Technically, the standard harvest site of cancellous bone tissue from the iliac crest is replaceable. The harvesting technique offers an interesting alternative also in terms of the duration of surgery and material. CONCLUSIONS Our study confirmed that by the minimally invasive technique of bone graft harvesting adequate amount of tissue to treat defect fractures and non-unions can be harvested. Spongioplasty using grafts harvested in this manner is effective, with a minimum percentage of non-unions. The advantage of this technique is the proximity of the harvest site and the operative field and low level of pain. The minimally invasive graft harvesting represents a technique with a low risk of postoperative and late complications. Key words: bone graft, autografts, minimally invasive surgery, ilium, pain.

[Comparison of Plaster Fixation and Kirschner Wire Transfixation as Temporary Fixation of Displaced Ankle Fractures - Randomised Prospective Study]. / Porovnání sádrové fixace a transfixace Kirschnerovými dráty pri docasné fixaci dislokovaných zlomenin hlezna ­ randomizovaná prospektivní studie.

PURPOSE OF THE STUDY The purpose of the study was to assess two therapeutic procedures of temporary fixation of displaced ankle fractures, namely the plaster fixation or Kirschner wire (KW) transfixation via the sole of the foot. MATERIAL AND METHODS Group of patients The randomised prospective study conducted in the period 02/2016-02/2017 compared two methods of temporary fixation of displaced ankle fractures. In total, 38 patients were included in the study (18 patients treated with plaster fixation, 20 patients treated with KW). Methods During the randomisation (by envelopes, drawing of lots by the patient), in one group of patients, temporary stabilisation by plaster fixation was performed, whereas the other group was treated by percutaneously inserted KWs. The attention was focused on the quality of achieved reduction, its retention until the final treatment, and soft tissue status. After one year, the final examination was performed, in which we focused on the assessment of the clinical condition of the ankle joint with the use of the Olerud-Molander Ankle Score (OMAS), the AOFAS (American Orthopedic Foot and Ankle Society) score, and the Visual Analogue Scale (VAS) measuring the overall satisfaction. Moreover, in both the methods potential incidence of arthritic changes was monitored on radiographs. RESULTS Both the methods achieved 100% successful reduction rate. The group with plaster fixation reported a loss of reduction in six patients (33.3%) as against the KW group where no loss of reduction occurred. This difference was significant (p = 0.007). In plaster fixation method, after its removal local complications occurred on skin in 56%, of which skin necrosis in 16.7%, and it always occurred in association with the loss of reduction, which was statistically significant (p = 0.245). In KW method, local complications on skin were present in 25% only. In the group of patients with KW, there was not a single case of surface or deep infection reported. No KW migration was observed. DISCUSSION Potential complications of conservative treatment of displaced fractures with plaster fixation include the migration of fragments and widening of the ankle fork during the further course which may threaten the vitality of soft tissues. A total of six patients (33.3%) treated with plaster fixation showed a failure of reduction, which is by approximately 10% more than described in literature. In seven cases after the plaster fixation removal bullae were observed (38.9%) and in three cases skin necrosis was present (16.7%), which occurred in re-displaced fractures only. The bullae were present whether the reduction was successfully maintained or not. In literature, local complications after plaster fixation removal are reported in roughly 14%. Temporary percutaneous ankle KW transfixation is applied to maintain the reduced fracture in a favourable position and to facilitate monitoring and treating the soft tissues. Prior to the final surgical solution, bullae were observedin four cases (20%), of which skin necrosis in one case (5%). Bullae formation and necrosis are most likely related to the initial damage to soft tissues due to the injury and were not caused by the KW insertion. The literature describes local complications in 7% with respect to the KW technique, however, the type of complications is not specified. In our group, at a one-year follow-up arthritic changes grade I and II according to Kellgren and Lawrence scale were reported in 70% of cases with KW technique. Whether the osteoarthritis was caused by fixation or the fracture itself and what would be the percentage of individual types of osteoarthritis after several years of follow-up is a question. CONCLUSIONS Plaster fixation or Kirschner wires for temporal fixation of displaced ankle fractures shall be applied on a case by case basis. Based on our findings, the application of plaster fixation to displaced ankle fractures does not provide adequate stability of the reduced fracture and in case of re-displacement the status of soft tissues deteriorates. The impossibility to control the status of soft tissues in plaster fixation and the lower complication rate in fixation with K wires constitute additional reasons why this fixation technique via the sole of the foot appears to reap more benefits. Key words:displaced ankle fractures, temporal fixation, plaster fixation, Kirschner wire transfixation, complications.

The Molecular Fingerprint of Fluorescent Natural Organic Matter Offers Insight into Biogeochemical Sources and Diagenetic State.

Investigating the biogeochemistry of dissolved organic matter (DOM) requires the synthesis of data from several complementary analytical techniques. The traditional approach to data synthesis is to search for correlations between measurements made on the same sample using different instruments. In contrast, data fusion simultaneously decomposes data from multiple instruments into the underlying shared and unshared components. Here, Advanced Coupled Matrix and Tensor Factorization (ACMTF) was used to identify the molecular fingerprint of DOM fluorescence fractions in Arctic fjords. ACMTF explained 99.84% of the variability with six fully shared components. Individual molecular formulas were linked to multiple fluorescence components and vice versa. Molecular fingerprints differed in diversity and oceanographic patterns, suggesting a link to the biogeochemical sources and diagenetic state of DOM. The fingerprints obtained through ACMTF were more specific compared to traditional correlation analysis and yielded greater compositional insight. Multivariate data fusion aligns extremely complex, heterogeneous DOM data sets and thus facilitates a more holistic understanding of DOM biogeochemistry.

Investigating Fluorescent Organic-Matter Composition as a Key Predictor for Arsenic Mobility in Groundwater Aquifers.

Dissolved organic matter (DOM) is linked to the heterogeneous distribution of elevated arsenic (As) in groundwater used for drinking and irrigation purposes, but the relationship between DOM characteristics and arsenic mobility has yet to be fully understood. Here, DOM from groundwater sampled in the Bengal Basin region was characterized using both conventional bulk emission-excitation (EEM) spectroscopy and high-performance size-exclusion chromatography coupled to spectroscopy (HPSEC-EEM). Notably, application of the novel HPSEC-EEM approach permitted the total fluorescence of individual samples to be independently resolved into its underlying components. This allowed the external validation of the bulk-sample fluorescence decomposition and offered insight into the molecular size distribution of fluorescent DOM. Molecular size distributions were similar for the UVA fluorescent (C310 and C340) as well as the three visible fluorescent (C390, C440, and C500) components. There was a greater visible fluorescence in shallow aquifer samples (10-33 m) with high As (SH, up to 418 µg/L) than in samples from the same depth with lower As (up to 40 µg/L). This indicated a link between DOM quality and As mobility within the shallow aquifer. The deep aquifer samples (170-200 m) revealed DOM characteristics similar to SH samples but had low As concentrations (<4 µg/L), signifying that the deep aquifer is potentially vulnerable to As contamination. These findings pave the way for a more comprehensive assessment of the susceptibility of drinking water aquifers, thereby supporting the management of groundwater resources.

Probing the Interlayer Exciton Physics in a MoS2/MoSe2/MoS2 van der Waals Heterostructure.

Stacking atomic monolayers of semiconducting transition metal dichalcogenides (TMDs) has emerged as an effective way to engineer their properties. In principle, the staggered band alignment of TMD heterostructures should result in the formation of interlayer excitons with long lifetimes and robust valley polarization. However, these features have been observed simultaneously only in MoSe2/WSe2 heterostructures. Here we report on the observation of long-lived interlayer exciton emission in a MoS2/MoSe2/MoS2 trilayer van der Waals heterostructure. The interlayer nature of the observed transition is confirmed by photoluminescence spectroscopy, as well as by analyzing the temporal, excitation power, and temperature dependence of the interlayer emission peak. The observed complex photoluminescence dynamics suggests the presence of quasi-degenerate momentum-direct and momentum-indirect bandgaps. We show that circularly polarized optical pumping results in long-lived valley polarization of interlayer exciton. Intriguingly, the interlayer exciton photoluminescence has helicity opposite to the excitation. Our results show that through a careful choice of the TMDs forming the van der Waals heterostructure it is possible to control the circular polarization of the interlayer exciton emission.

Susceptibility of clinical isolates of Bordetella pertussis to chemicals.

THE AIM OF STUDY: To test clinical isolates of Bordetella pertussis from the National Reference Laboratory for Pertussis and Diphtheria for susceptibility to commonly available disinfectants. Another aim was to determine the concentration and exposure time for each chemical under real conditions of use and possibly to detect the emergence of resistance to disinfectants among 34 strains of B. pertussis referred to the National Reference Laboratory for Pertussis and Diphtheria in 2014 and 2015. MATERIAL AND METHODS: A total of 34 clinical isolates of Bordetella pertussis were tested for susceptibility to chemical disinfectants by three different methods. The microsuspension method was used for the primary screening, and the tests were carried out without protein contamination. Further testing was conducted in accordance with standard EN 14885, where the test procedure consists of several steps. Step 1 involves quantitative suspension methods (Phase 2, Step 1), and step 2 uses methods designed for practice (Phase 2, Step 2). The quantitative suspension method modified according to EN 13727+A2 was used in step 1 to confirm bactericidal activity of the test products under the dirty conditions. In step 2, clinical isolates were tested using a quantitative carrier test method under the dirty conditions modified according to EN 14561. Based on this standard, the real conditions of product use are simulated. Four disinfectants differing in composition and intended use were tested. RESULTS: Disinfectant No. 1 showed bactericidal activity at a concentration of 0.5% after 2 min of exposure in the case of immersion or at a concentration of 5% after 2 min of exposure when treated by wiping. Disinfectant No. 2 was active at a concentration of 0.1% after 2 min of exposure or at a concentration of 1% after 2 min of exposure, respectively. Disinfectant No. 3 did not show bactericidal activity even at a concentration of 100% after 5 min of exposure. Disinfectant No. 4 showed bactericidal activity at a concentration of 10% after 5 min of exposure or at a concentration of 30% after 2 min of exposure. CONCLUSIONS: None of the strains tested was resistant. Using the methods that simulate the real conditions of use of disinfectants Nos. 1 and 2, it was possible to determine the concentration and exposure time needed to achieve disinfection of surfaces under the dirty conditions. Disinfectants Nos. 3 and 4 are not primarily intended for the treatment of surfaces but for the treatment of the skin and mucous membranes. The results obtained with the latter two products are interesting but inconclusive as the real conditions of their use were not simulated accurately. KEYWORDS Bordetella pertussis - susceptibility - disinfectants.

The One-Sample PARAFAC Approach Reveals Molecular Size Distributions of Fluorescent Components in Dissolved Organic Matter.

Molecular size plays an important role in dissolved organic matter (DOM) biogeochemistry, but its relationship with the fluorescent fraction of DOM (FDOM) remains poorly resolved. Here high-performance size exclusion chromatography (HPSEC) was coupled to fluorescence emission-excitation (EEM) spectroscopy in full spectral (60 emission and 34 excitation wavelengths) and chromatographic resolution (<1 Hz), to enable the mathematical decomposition of fluorescence on an individual sample basis by parallel factor analysis (PARAFAC). The approach allowed cross-system comparisons of molecular size distributions for individual fluorescence components obtained from independent data sets. Spectra extracted from allochthonous DOM were highly similar. Allochthonous and autochthonous DOM shared some spectra, but included unique components. In agreement with the supramolecular assembly hypothesis, molecular size distributions of the fluorescence fractions were broad and chromatographically unresolved, possibly representing reoccurring fluorophores forming noncovalently bound assemblies of varying molecular size. Samples shared underlying fluorescence components that differed in their size distributions but not their spectral properties. Thus, in contrast to absorption measurements, bulk fluorescence is unlikely to reliably indicate the average molecular size of DOM. The one-sample approach enables robust and independent cross-site comparisons without large-scale sampling efforts and introduces new analytical opportunities for elucidating the origins and biogeochemical properties of FDOM.

Comparison of central and local serial CT assessments of metastatic renal cell carcinoma patients in a clinical phase IIB study.

Background Clinical oncological studies attempt to improve precision of data by central radiological assessments. However, it is unclear, to which extent local and central assessments diverge. Purpose To quantify inter-reader variability and the deviation of local from central radiological assessments of computed tomography (CT) scans. Material and Methods This was a sub-study of a randomized clinical phase IIb trial in metastatic renal cell carcinoma (RCC), comparing first-line sorafenib with interferon-alpha-2a (IFN-α-2a). It analyzed agreements of local with central RECIST CT assessments by Cohen's kappa (κ), symmetry tests, deviations in waterfall plots, Bland-Altman plots, and parametric survival analyses. Results The concordance between local and central radiologic review was quantified by κ = 0.53. While local assessment yielded progressive disease (PD) in 18.6%, central assessment classified 22.5% of patient time points as PD exhibiting only a partial overlap with the 18.6% The tumor shrinkage rates in waterfall plots were 68.1% in local and 55.8% in central review (57.8% and 59% by Reader 1 and Reader 2). Bland-Altman plots identified a systematic shift of tumor change rates by -7.5% in local compared to central assessments, that may reflect a systematic tendency of more favorable results in local assessments. The discordance between local and central review was reflected by a time to progression (TTP) hazard ratio (HR) of 1.73 ( P = 0.0003). Conclusion These data suggest that central radiologic review may reduce technical measurement variability in clinical trials, which should be scrutinized in future studies compared to a volumetric reference.

The potential protective effect of Commelina nudiflora L. against carbon tetrachloride (CCl4)-induced hepatotoxicity in rats, mediated by suppression of oxidative stress and inflammation.

BACKGROUND: This study aims to assess the hepatoprotective potential of Commelina nudiflora against CCl4-induced hepatic injury in rats. METHOD: Antioxidant activities were determined. Phytochemical analysis was performed by gas chromatography mass spectrometry (GCMS). In the in vivo study, Sprague Dawley rats were pretreated with C. nudiflora (150, 300, and 450 mg kg body weight (b.wt.)) once daily for 14 days followed by two doses of CCl4 (1 ml/kg b.wt.). After 2 weeks, the rats were sacrificed and hepatoprotective analysis was performed. RESULTS: In vitro studies have shown that the extract possessed strong antioxidant activity and has ability to scavenge 2,2-diphenyl-2-picrylhydrazyl-free radicals effectively. GCMS analysis of the C. nudiflora extract revealed the presence of various bioactive compounds. Administration of C. nudiflora significantly reduced the impact of CCl4 toxicity on serum markers of liver damage, serum aspartate transaminase (AST), and alanine transaminase (ALT). C. nudiflora also increased antioxidant levels of hepatic glutathione (GSH) and antioxidant enzymes and ameliorated the elevated hepatic formation of malondialdehyde (MDA) induced by CCl4 in rats. Histopathological examination indicated that C. nudiflora protect the liver from the toxic effect of CCl4 and healed lesions such as necrosis, fatty degeneration, and hepatocyte injury as irregular lamellar organization and dilations in the endoplasmic reticulum. The immunohistochemical studies revealed that pretreatment of C. nudiflora decreased the formation of 4-hydroxy-2-nonenal (HNE)-modified protein adducts and 8-hydroxy-2'-deoxyguanosine (8-OHdG). Furthermore, overexpression of the proinflammatory cytokines TNF-α, IL-6, and prostaglandin E2 is also reduced. CONCLUSION: These findings exhibited the potential prospect of C. nudiflora as functional ingredients to prevent ROS-related liver damage.

[Long-Term Outcomes of the Treatment of Pediatric Femoral Shaft Fractures Treated with Bryant's Vertical Traction]. / Dlouhodobé výsledky lécby zlomenin diafýzy femuru u detí lécených Bryantovou vertikální trakcí.

PURPOSE OF THE STUDY The paper aimed to evaluate the long-term outcomes of the treatment of diaphyseal femur fractures in children treated with Bryant's vertical traction. Moreover, we also assessed the size of overgrowth in the injured femur. MATERIAL AND METHODS The study included 23 patients with 23 femoral shaft fractures treated with Bryant's vertical traction at our department in 2009-2014. The following parameters were assessed: sex, ïnjured side, weight, age, mechanism of injury, potential abuse, type of fracture, duration of traction, and total length of hospital stay. The healing time of the fracture was the same as the duration of traction. Also assessed was the size of femoral shortening after the removal of traction, the presence of skin complications in the course of treatment and potential development of compartment syndrome. At the mean follow-up of 47.8 months (range 22-85 months) from the date of injury the patients were evaluated clinically and radiologically for: length of limbs, presence of rotational deformity, range of motion of knee and hip joints, potential pain or limping, potential scoliosis of the spine and presence of scars after traction. Finally, through a questionnaire we learned about the opinions of parents as to the treatment method and about the possibility of home traction. RESULTS All the fractures healed. There was a total of 17 injured boys and 6 injured girls. Whereas 12 patients sustained a fracture of the left femur, 11 patients sustained a fracture of the right femur. The mean weight of patients at the time of injury was 13.9 kg (range 5-20 kg). The mean age at the time of traction was 30.8 months (range 1-70 months). The injury most frequently occurred from various falls, altogether in 15 cases (65.2%). Traffic accidents were registered as the cause of injury in 3 cases (13%). No abuse was confirmed. The average duration of traction was 19.8 days (range 8-26 days). The total length of hospital stay took on average 23.6 days (range 9-33 days). Skin excoriation and bullae due to irritation by the traction occurred in 21 children (91.3% cases). All the bullae healed, in 4 (17.4%) patients minor scars of 1x1 cm in size were formed around ankles. Not a single patient developed the compartment syndrome. The average femoral shortening after the removal of traction was 0.8 cm (range 0-2.3 cm). The follow-up examination, performed on average 47.8 months (range 22-85 months) from the date of injury revealed the average discrepancy of spinomalleolar distances in both the lower limps of 0 cm (range -1 to 1 cm). Radiographically measured lengths of both the femurs showed the average difference of 0 cm (range -1.4 to 0.9 cm). The resulting average overgrowth of injured femur was 0.9 cm (range 0.1 to 3.2 cm). Scoliosis of the spine was not reported in any of the patients. In 3 patients femur alignment demonstrated rotation, namely an external rotation of 10° in all the cases. All the children demonstrated full hip and knee joint mobility, identical to the uninjured side. After a heavy load one patient reported pain in the thigh and one walked with limp. The other patients showed no problems whatsoever. Treatment with the use of Bryant's traction was well tolerated by parents. Altogether 15 parents (65.2%) would opt for the same treatment method in case of a recurrent injury. The home traction option would be welcomed by 17 parents (73.9%). DISCUSSION The treatment by Bryant's vertical traction is condemned in Anglo-Saxon countries due to the risk for developing compartment syndrome, described in earlier studies. Neither our cohort, nor more recent studies reported the occurrence of compartment syndrome. The most frequent complication faced in our study was the skin complications underneath the traction, namely in a total of 91.3% of patients. In the literature, the other authors only make references to bullae occurrence, but do not provide any further specifications. Overgrowth after femoral shaft fractures is a very well described phenomenon. The size of femoral overgrowth described in our study was similar to that referred to in the available literature. A method frequently used abroad is the so-called home traction. This method, however, has so far failed to take root in our country, even though this therapeutic technique would be appreciated by parents. CONCLUSIONS The treatment of femoral shaft fractures by Bryant's vertical traction, in children up to the weight of 15 kg, is a simple and safe method with excellent functional outcomes and minimum serious complications. When treating the children with the body weight more than 15 kg, the risk of bullae formation increases, therefore in this weight category treatment shall be decided upon on a case by case basis. The resulting average overgrowth of injured femur was 0.9 cm which corresponds with the findings of other authors. The treatment method using the Bryant's traction is well tolerated by parents, even though most of them would welcome the option of home traction. Key words: traction, femur fracture, overgrowth, children.

[Treatment of Displaced Patellar Fractures with Multiple Circular Cerclage]. / Lécba dislokovaných zlomenin césky etázovou cerklází.

PURPOSE OF THE STUDY The study aims to conduct a mid-term evaluation of results of the treatment of patellar fractures with multiple circular cerclage. MATERIAL AND METHODS The retrospective clinical study with its own group of patients who underwent surgery in our centre in the period from 2008 to 2014. The study included a total of 29 patients with displaced patellar fractures treated with multiple circular cerclage. The available radiographic documentation was assessed and the quality of perioperative reposition, fracture healing, loss of reposition and potential failure of osteosynthesis material was considered. During the clinical examination, the range of motion (ROM) of the operated knee was measured. The current pain was evaluated on the Visual Analogue Scale for Pain (VAS). For evaluation of functional outcomes, the KOOS and LEFS scoring systems were used. RESULTS A total of 27 fractures (93.1%) healed after a mean period of 10.3 weeks after the primary surgery. In 23 cases two circular loops and in six cases 3 loops were used. The mean follow-up period was 66.6 months (range 22-100). The mean duration of the surgery was 59.6 minutes with the mean length of the incision of 11.8 cm (range 9-15). The quality of reposition was evaluated as exact in 23 patients, as adequate in six patients. The mean extension and flexion was 0.2° and 135°, respectively. The individual mean KOOS scores were the following: pain 75.0, symptom 74.5, knee function in daily living 76.7, knee function in sports and recreational activities 48.1, quality of life 57.8. The mean LEFS score was 68.7. The mean VAS score was 2.4. Extraction of osteosynthesis material was done in a total of seventeen cases (58.6%) at a mean of 10 months after osteosynthesis (range 5-14). In altogether five cases (17.2%) the loss of reposition occurred. In two patients pseudoarthrosis developed. Osteosynthesis material failure was reported in two cases (6.9%). DISCUSSION In our study population, by using the technique of multiple circular cerclage 27 fractures (93.1%) healed. In two cases the fractures failed to heal and pseudoarthrosis developed. In one case it was due to non-adherence to the postoperative regimen by the patient. According to the literature, 15-30% of patients suffer from functional limitations. In our study population the mean values of extension and flexion were 0.2° and 135°, respectively. Compared to the group of 17 patellar fractures managed with the modified Pyrford technique where the mean extension and flexion was 0.5° and 131.1°, respectively. According to the data referred to in literature, in up to 80 % cases post-operative pain of anterior knee is reported. In our population the current pain was assessed on the VAS and the mean value of 2.4 was ascertained in comparison to the set of different ORIF surgical procedures and a partial patellectomy, when the final mean VAS score was 2.8. In our population the values of LEFS and KOOS scores are comparable to the values of populations where different surgical techniques were assessed. The post-operative loss of reposition in up to 20% cases is reported by the literature, compared to our population, where it was recorded in a total of 5 cases (17.2%). CONCLUSIONS Multiple circular cerclage is a simple and inexpensive surgical method for treating displaced patellar fractures. It can be used for majority of types of fracture, including comminuted fractures, in which, however, there is a slightly higher risk of loss of reposition. The functional outcomes and the number of complications are comparable to other surgical techniques used. Key words: displaced patellar fracture, multiple circular cerclage, functional outcomes.

In situ Raman spectroscopy of the graphene/water interface of a solution-gated field-effect transistor: electron-phonon coupling and spectroelectrochemistry.

We present a novel measurement approach which combines the electrical characterization of solution-gated field-effect transistors based on epitaxial bilayer graphene on 4H-SiC (0001) with simultaneous Raman spectroscopy. By changing the gate voltage, we observed Raman signatures related to the resonant electron-phonon coupling. An analysis of these Raman bands enabled the extraction of the geometrical capacitance of the system and an accurate calculation of the Fermi levels for bilayer graphene. An intentional application of higher gate voltages allowed us to trigger electrochemical reactions, which we followed in situ by Raman spectroscopy. The reactions showed a partially reversible character, as indicated by an emergence/disappearance of peaks assigned to C-H and Si-H vibration modes as well as an increase/decrease of the defect-related Raman D band intensity. Our setup provides a highly interesting platform for future spectroelectrochemical research on electrically-induced sorption processes of graphene on the micrometer scale.