Motility and the genotype diversity of the flagellin genes fliC and fliD among Clostridioides difficile ribotypes.

OBJECTIVE: The motility and genotype of the flagellin fliC and fliD genes were investigated in 82 Clostridioides difficile isolates belonging to the ribotypes (RTs): 027 (n = 41), 176 (n = 17), 023 (n = 8), 017 (n = 6) and 046 (n = 10). The reference C. difficile strains 630 and M120 were included as controls for the motility assay. METHODS: A Multiple Locus Variable-number Tandem Repeat Analysis (MLVA) was used to exclude the genetic relatedness of C. difficile isolates belonging to the same RT. The variability of the fliC and fliD genes was determined by PCR-restriction fragment length polymorphism (RFLP) analysis and Sanger sequencing. The motility assay was carried out with 0.175% BHI agar tubes and BHI solid media plates with 0.4% agar. RESULTS: The highest motility was observed in C. difficile RT023 isolates (p < 0.01), followed by RTs 027 and 176. C. difficile isolates of RTs 017 and 046 were less motile than RTs 027, 176 and 023 (p < 0.01). The fliC and fliD genes were present in all clinical isolates irrespective of the motility results. In the fliC gene analysis, four different RFLP groups were identified (I, II, VII, X). The fliC group VII was identified in two RTs (027 and 176), whereas the remaining three groups (I, II and X) belonged to a single RT 046, 017 and 023, respectively. The fliD gene analysis identified four new RFLP groups (a, b, c and d). CONCLUSIONS: C. difficile RT023 is highly motile and its motility is comparable to the hypervirulent RT027 and its genetic relative RT176.

The effect of berberine chloride and/or its combination with vancomycin on the growth, biofilm formation, and motility of Clostridioides difficile.

This study aims to investigate the antimicrobial and antibiofilm activity of berberine chloride (BBR) and vancomycin (VAN) as well as synergistic combinations of BBR with VAN against Clostridioides difficile strains. The effect of different concentrations of BBR on strain motility was also assessed. Twelve C. difficile strains (two reference C. difficile 630, ATCC 9689, and one control M120, and 9 clinical C. difficile strains belonging to the PCR-ribotype (RT027)) were collected and investigated for their susceptibility to BBR and VAN in planktonic and biofilm forms. Both the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of BBR for the C. difficile strains were found to vary over a broad range (256-1.024 mg/L and 256-16.384 mg/L, respectively). The MIC and MBC of VAN also varied greatly, ranging from 0.25 to 4.0 mg/L for MIC and 0.25 to 64.0 mg/L for MBC. The synergistic effect of the sub-MIC (1/2 MIC) BBR with VAN reduced of MICs of VAN against the planktonic forms of ten C. difficile strains. The sub-MIC of BBR enhanced the biofilm formation of one strain and was found to be statistically significant. In addition, the sub-MIC of BBR with VAN surprisingly enhanced the biofilm formation of one C. difficile strain. The effect of inhibition of motility in the presence of BBR was statistically significant for 3 clinical strains (p < 0.05). Altogether, BBR exhibited strong antimicrobial activity against C. difficile, and the analysis of the combination of BBR with VAN showed a synergistic effect.

Fructooligosaccharides and mannose affect Clostridium difficile adhesion and biofilm formation in a concentration-dependent manner.

The aim of this study was to investigate the effects that prebiotic and candidates for prebiotics on Clostridium difficile strains to adhere to various human epithelial cell lines and to compare the adhesive properties of specific C. difficile strains. We also sought to examine the effect of different concentrations of fructooligosaccharides and mannose on the formation of biofilms by C. difficile strains. The influence of cellobiose, fructooligosaccharides, inulin, mannose, and raffinose on the adherence properties of various C. difficile strains, including motile 630, non-motile M120, and 10 clinical motile ribotype 027 strains, to non-mucous secreting HT-29, mucous secreting HT-29 MXT, and CCD 841 CoN cells lines. The most effective prebiotics were used in biofilm formation assays. We demonstrated that all C. difficile strains adhered to all cell lines. However, the C. difficile M120 non-motile strain was statistically more likely to adhere to all three cell lines (CFU median, 40) compared to the motile strains (CFU median, 3; p < 0.001). Furthermore, among the carbohydrates examined, only fructooligosaccharides and mannose were found to significantly decrease adhesion (p < 0.001) of C. difficile strains. Alternatively, using a biofilm assay, we observed, via confocal laser scanning microscopy, that sub-inhibitory concentrations (1%) of fructooligosaccharides and mannose functioned to increase biofilm formation by C. difficile. We demonstrated that specific prebiotics and candidate prebiotics exhibit varying anti-adhesive properties towards C. difficile in vitro and that treatment with sub-inhibitory concentrations of prebiotics can cause an increase in biofilm formation by C. difficile.

The level of fecal calprotectin significantly correlates with Clostridium difficile infection severity.

INTRODUCTION: Fecal calprotectin (FC) rises significantly in intestinal inflammation accompanied by neutrophil activation - such as Clostridium difficile infection (CDI). The aim of the study was to evaluate the benefit of FC testing in assessing the severity of CDI. MATERIALS AND METHODS: The study group included 76 patients with CDI hospitalized in the Jagiellonian University Hospital in Krakow from July 2017 till January 2018. FC levels were measured using an EIA (Enzyme Immunoassay). Demographic, clinical information and blood tests were recorded using standardized data collection forms. The selection of patients into non-severe and severe groups was carried out in accordance with the ESCMID criteria (European Society of Clinical Microbiology and Infectious Diseases) and some modi cations to those criteria were proposed. RESULTS: the studied population included 76 patients (39 men and 37 women) with CDI aged from 24 to 98 years (mean: 72). Median calprotectin level was 739 (Q25-Q75: 612-799 µg/g), characteristic of patients with colitis. A statistically significant difference in FC concentration in patients with severe vs non-severe CDI was observed (severe - 770 vs non-severe - 659 µg/g, p = 0.009). FC directly correlated with platelets level; however, no correlation between FC level and the blood parameters prognostic for CDI (leukocyte, neutrophil count, albumin, creatinine levels) was found. CONCLUSION: FC level is an indication of ongoing intestinal inflammation in CDI patients. FC level significantly correlated with CDI severity, which demonstrates that FC could serve as a predictive marker for assessing CDI severity.

A malignant astrocytoma with uncommon angiocentric features and dot-like EMA expression.

Angiocentric features are uncommon in high-grade World Health Organisation (WHO) brain tumours, whilst they are typical for WHO grade I tumours, e.g. angiocentric gliomas. We present an unusual glial tumour that occurred in a 59-year-old man. The tumour had equivocal radiologic and histopathologic features, especially a characteristic angiocentric pattern, low-to-moderate Ki67, and dot-like epithelial membrane antigen expression. The tumour did not show features characteristic for glioblastoma; however, it recurred as glioblastoma four months later. Based on this case, we show that high-grade WHO brain tumours may show an angiocentric pattern typical for low-grade WHO brain tumours, such as angiocentric gliomas.

[Evaluation of growth of clinical Clostridium difficile strains belonging to different PCR-ribotypes on chromID C. difficile Agar]. / Ocena wzrostu na podlozu chromID C. difficile Agar klinicznych szczepów Clostridium difficile nalezacych do róznych PCR-rybotypów.

INTRODUCTION: Clostridium difficile is main reason of antibiotic-associated diarrhea in hospitalized patients. Diagnostic method for detection of Clostridium difficile infection (CDI) are limited to an enzyme immunoassays (EIAs), while the culture of toxigenic strains is still seen as the gold standard for the laboratory diagnosis. The aim of this study was to compare growth of C. difficile strains belonging to different polymerase chain reaction (PCR) ribotypes on new ChromID C. difficile Agar (CDIFF, bioMérieux, Marcy l'Etoile, France). MATERIALS AND METHODS: One hundred thirty one of clinical C. difficile strains stored. in Anaerobic Laboratory were cultured on ChromID C. difficile Agar. Ten faecal samples were cultured on the same chromogenic medium and incubated at 37°C for 24 h under anaerobic conditions. Isolates were confirmed as C. difficile on the basis of well-known criteria. PCR-ribotyping was performed by visually comparison of patterns of PCR products of the 16S-23S rRNA intergenic spacer region. We examined the occurrence of beta-glucosidase gene, responsible for the dark color of the colony C. difficile on ChromID C.difficile Agar using a pair of primers: gluF (5'-AAGGT GTAAATTTAGGAGGTTGGTT-3') i gluR (5'-AGGTCCCAACTATCCC ATCC-3'). RESULTS: Among ten C. dfficile isolates obtained from stool specimens one formed colorless colonies. We received 8 colorless isolates from 131 additional examined strains. All C. difficile isolates forming colorless colonies belonged to PCR ribotype 023. The prevalence of PCR-ribotype 023 was about 6%. We detected lack of beta-glucosidase gene in PCR-ribotype 023 isolates. CONCLUSIONS: There are some C. difficile strains forming colorless colonies on ChromID C.difficile Agar. This appearance is important in routine diagnostic use this chromogenic culture medium.

Effect of Testing Conditions on Low-Cycle Fatigue Durability of Pre-Strained S420M Steel Specimens.

S420M steel subjected to strain-controlled low-cycle fatigue does not exhibit a period of cyclic properties stabilization. The maximum stress on a cycle continuously drops until fracture. For this reason, it is difficult to plan experimental research for different types of control in such a way that their results can be considered comparable. The aim of this paper is to present and discuss the results of tests conducted in various conditions of low-cycle fatigue of S420M steel specimens, both undeformed and pre-strained. In both loading conditions, after initial deformation, a significant change in the cyclic properties of steel described by the parameters of the hysteresis loop was observed. Also, the fatigue life of the pre-strained specimens appeared to be different from unstrained specimens and was affected by the test loading conditions. The reduction in life under controlled stress conditions was attributed to the increase in the extent of plastic deformation and stress and the occurrence of creep.

Antimicrobial Effects of Some Natural Products on Adhesion and Biofilm Inhibition of Clostridioides difficile.

Understanding the potential antimicrobial properties of natural compounds and their impacts on Clostridioides difficile virulence factors may aid in developing alternative strategies for preventing and treating C. difficile infections (CDI). In this study, we investigated the bactericidal effects of ginger oil (GO), peppermint oil (PO), curcumin (CU), cinnamon aldehyde (CI), and trans-cinnamaldehyde (TCI) on the adhesion and biofilm disruption of C. difficile. We used three reference and five clinical C. difficile strains of different ribotypes. The bactericidal activity was assessed using the broth microdilution method. The adhesion was evaluated using human epithelial cell lines, and biofilm formation was visualized by confocal laser scanning microscopy. All tested strains exhibited susceptibility to CU, with minimum inhibitory concentration (MIC) values ranging from 128 µg/mL to 2048 µg/mL. Similarly, all strains were susceptible to CI and TCI, with MIC values ranging from 6.25% (v/v) to 25% (v/v). Most of the tested substances reduced the adhesion of C. difficile strains, while two tested strains showed significantly higher adhesion when co-incubated with the tested substances. Similar observations were made for biofilm formation, with observed density and morphology varied depending on the strain. In conclusion, the tested products demonstrated bactericidal activity and reduced the adhesion of C. difficile strains. They may be considered for further studies as potential antimicrobial agents targeting biofilm-related infections.

On the Use of the Fricke-Pluronic F-127 Gel Dosimeter for Radiation Isocenter Testing of a Medical Linear Accelerator.

This work presents a Fricke-XO-Pluronic F-127 2D radiochromic dosimeter with a flat-bed scanner for 2D reading and a dedicated data processing software package as a tool for performing coincidence testing of the radiation and mechanical isocenter of a medical accelerator. The optimal irradiation parameters were determined as follows: monitor units per beam and multi-leaf collimator gap, which are ≤750-≤2500 MU and 2-5 mm, respectively, for a cuboidal container with dimensions of 12 × 12 × 0.3 cm3. Despite the diffusion of Fe3+ ions occurring during irradiation, 2D reading can be performed at least 3 h after irradiation, without affecting the calculation performance of the coincidence test. The test was successfully performed for various irradiation settings. Overall, the Fricke-XO-Pluronic F-127 dosimeter has proven to be a potential tool for the coincidence testing of medical accelerators.

The Right Coronary Anatomy and Operative Topography of the Tricuspid Valve Annulus.

BACKGROUND: The region of the tricuspid valve is an important area for various cardiac interventions. In particular, the spatial relationships between the right coronary artery and the annulus of the tricuspid valve should be considered during surgical interventions. The aim of this study was to provide an accurate description of the clinical anatomy and topography of this region. METHODS: We analyzed 107 computed tomography scans (44% female, age 62.1 ± 9.4 years) of the tricuspid valve region. The circumference of the free wall of the tricuspid valve annulus was divided into 13 annular points and measurements were taken at each point. The prevalence of danger zones (distance between artery and annulus less than 2 mm) was also investigated. RESULTS: Danger zones were found in 20.56% of the cases studied. The highest prevalence of danger zones and the smallest distances were found at the annular points of the tricuspid valve located at the posterior insertion of the leaflets, without observed sex-specific differences. CONCLUSION: The highest risk of iatrogenic damage to the right coronary artery is in the posterior part of the tricuspid valve annulus.

The Anterior Inferior Cerebral Artery Variability in the Context of Neurovascular Compression Syndromes: A Narrative Review.

The anterior inferior cerebellar artery (AICA) is situated within the posterior cranial fossa and typically arises from the basilar artery, usually at the pontomedullary junction. AICA is implicated in various clinical conditions, encompassing the development of aneurysms, thrombus formation, and the manifestation of lateral pontine syndrome. Furthermore, owing to its close proximity to cranial nerves within the middle cerebellopontine angle, AICA's pulsatile compression at the root entry/exit zone of cranial nerves may give rise to specific neurovascular compression syndromes (NVCs), including hemifacial spasm (HFS) and geniculate neuralgia concurrent with HFS. In this narrative review, we undertake an examination of the influence of anatomical variations in AICA on the occurrence of NVCs. Significant methodological disparities between cadaveric and radiological studies (CTA, MRA, and DSA) were found, particularly in diagnosing AICA's absence, which was more common in radiological studies (up to 36.1%) compared to cadaver studies (less than 5%). Other observed variations included atypical origins from the vertebral artery and basilar-vertebral junction, as well as the AICA-and-PICA common trunk. Single cases of arterial triplication or fenestration have also been documented. Specifically, in relation to HFS, AICA variants that compress the facial nerve at its root entry/exit zone include parabola-shaped loops, dominant segments proximal to the REZ, and anchor-shaped bifurcations impacting the nerve's cisternal portion.

Influence of Pre-Strain on Static and Fatigue Properties of S420M Steel.

This paper reports the results of static tensile and low-cycle fatigue tests on S420M steel specimens. As-received (unstrained) and pre-strained specimens were used during the tests. Based on the static tensile tests carried out, no effect of pre-strain on the basic strength parameters of the S420M steel was found. Low-cycle fatigue tests showed that the pre-strain of the specimens causes a change in the cyclic properties of the steel and a slight increase in fatigue life compared to that of the as-received specimens. The greatest increase in durability was observed at the lowest strain levels.

The Effect of Subinhibitory Concentration of Metronidazole on the Growth and Biofilm Formation on Toxigenic Clostridioides difficile Strains Belonging to Different Ribotypes.

Clostridioides difficile is a predominant nosocomial pathogen within the healthcare setting able to produce biofilms. Sub-minimum inhibitory concentrations (sub-MICs) of antibiotics trigger mechanisms affecting bacterial virulence, including increased adhesion and biofilm formation. The aim of this study was to investigate how sub-MICs of metronidazole affect the biofilm formation of C. difficile strains. We tested 14 reference and clinical C. difficile strains, including hypervirulent strains of RT027. The MICs of metronidazole for the tested strains were determined using the broth microdilution method. Biofilm formation was evaluated using confocal laser scanning microscopy. The C. difficile strains belonging to RT027 produced the highest amounts of biofilm. The results of confocal laser scanning microscopy showed that all the tested C. difficile strains developed larger biofilms with diversified architectures upon exposure to sub-MICs of metronidazole. In our study, we reveal that sub-MIC concentrations of metronidazole affect the biofilm formation of clinical and reference strains of C. difficile. Importantly, metronidazole induces biofilm formation via hypervirulent RT027 strains.

The Superior Cerebellar Artery: Variability and Clinical Significance.

The superior cerebellar artery (SCA) arises from the distal part of the basilar artery and passes by the oculomotor, trochlear, and trigeminal nerves. SCA is known to play a crucial role in the development of trigeminal neuralgia. However, due to its anatomical variability, it may also trigger other neurovascular compression (NVC), including hemifacial spasm, oculomotor nerve palsy, and ocular neuromyotonia. Additionally, it may be associated with ischemic syndromes and aneurysm development, highlighting its clinical significance. The most common anatomical variations of the SCA include duplication, a single vessel origin from the posterior cerebral artery (PCA), and a common trunk with PCA. Rarely observed variants include bifurcation and origin from the internal carotid artery. Certain anatomical variants such as early bifurcation and caudal course of duplicated SCA trunk may increase the risk of NVC. In this narrative review, we aimed to examine the impact of the anatomical variations of SCA on the NVCs based on papers published in Pubmed, Scopus, and Web of Science databases with a snowballing approach. Our review emphasizes the importance of a thorough understanding of the anatomical variability of SCA to optimize the management of patients with NVCs associated with this artery.

Morphology and Anatomical Classification of Pericardial Cavities: Oblique and Transverse Sinuses.

The pericardial sinuses are an important anatomical feature of the pericardial cavity, however, their clinical anatomy has not been thoroughly studied. In this study, we aim to provide the first classification of the oblique and transverse sinuses. We analyzed 121 computer tomography scans (46.3% female, age of 66 ± 12 years) of the pericardial cavity. The oblique sinuses were classified into four types: 1 (shallow with narrow entrance), 2 (shallow with wide entrance), 3 (deep with narrow entrance), and 4 (deep with wide entrance). The transverse sinuses were classified into four types: Concave, Wine-type, Straight, and Convex. The most common oblique sinus type was Type 1. The median oblique sinus volume was 8.4 (5.3) mL, the median entrance length was 33.0 (13.2) mm, and the depth was 38.2 (11.8) mm. The most common transverse sinus type was Concave. The median transverse sinus volume was 14.8 (6.5) mL, and the median length was 52.8 (17.7) mm. Our study provides an anatomical classification of the pericardial sinuses. The individual variability of the sinuses' morphology highlights the importance of understanding the clinical topography of the sinuses, particularly for minimally invasive thoracic ablation procedures.

Effect of prebiotics on Bacteroides sp. adhesion and biofilm formation and synbiotic effect on Clostridioides difficile.

Aim: The objective of this study was to determine the effect of standard and candidate prebiotics on the adhesion and biofilm formation of Bacteroides sp. in monoculture and co-culture with Clostridioides difficile. Materials & methods: The effect of seven prebiotics on the adhesion and biofilm formation of Bacteroides sp. to three human cell lines was determined. The effect of Bacteroides sp. and fructooligosaccharides (FOS) on the adhesion and biofilm formation of C. difficile was tested by the co-incubation assay. Results: Inulin, mannose and raffinose presented the best anti-adhesion properties against Bacteroides sp. Combination of Bacteroides sp. with FOS decreased the adhesion of C. difficile. Conclusion: The study shows the potential role of prebiotics and synbiotics in decreasing the burden of C. difficile infections.

The prebiotic effect of human milk oligosaccharides 3'- and 6'-sialyllactose on adhesion and biofilm formation by Clostridioides difficile - pilot study.

Bacterial adhesion is the first stage of colonisation and biofilm formation by Clostridioides difficile. Cell wall proteins (Cwp) 84 and 66 play crucial roles in the pathophysiology of C. difficile and may affect bacterial adhesion. Sialylated human milk oligosaccharides (HMOs) have potential to inhibit bacterial adhesion in vitro. The aim of this study was to investigate how 3'-sialyllactose (SL) and 6'-SL affect adhesion and C. difficile biofilm formation. Also, the influence of these substances on cwp84 and cwp66 genes expression by C. difficile was assessed. An adhesion assay was performed using three human colon cells in vitro, and biofilm formation was evaluated using crystal violet staining and confocal laser scanning microscopy. The effect of 3'-SL and 6'SL on cwp expression was measured using real time-PCR. Both tested HMOs decreased expression of the cwp84 gene, adhesion of C. difficile to human colon cells in vitro and biofilm formation.

Study of the Optimal Composition and Storage Conditions of the Fricke-XO-Pluronic F-127 Radiochromic Dosimeter.

This paper presents the results of research on the Fricke-XO-Pluronic F-127 dosimeter. It consists of a Fricke dosimetric solution and xylenol orange (XO), which are embedded in a matrix of poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (Pluronic F-127). Upon irradiation, Fe+2 ions transform into Fe+3, forming a colored complex with XO ([XO-Fe]+3). The color intensity is related to the dose absorbed. The optimal composition, storage conditions, and radiation-induced performance of the Fricke-XO-Pluronic F-127 dosimeter were investigated. The optimal composition was found to be 1 mM FAS, 50 mM sulfuric acid (H2SO4), 0.165 mM XO in 25% Pluronic F-127. The basic features of this dosimeter are discussed, such as dose sensitivity, linear and dynamic dose range, stability before and after irradiation, storage conditions, dose response for irradiation with 6 and 15 MV photons, and batch-to-batch reproducibility. The obtained results showed a certain potential of the Fricke-XO-Pluronic F-127 for radiotherapy dosimetry.

Impact of Salt on Thermal Stability and Dose Response of the Fricke-XO-Pluronic F-127 3D Radiotherapy Dosimeter.

Fricke-XO-Pluronic F-127 has recently been proposed as a 3D dosimeter for radiotherapy. It contains the typical ingredients of the Fricke ionizing radiation dosimeter, which are embedded in a physical gel of poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (Pluronic F-127). The main reactions upon irradiation are the conversion of Fe+2 to Fe+3 and the formation of a colored complex with XO ([XO-Fe]+3). The study attempts to optimize the dosimeter in terms of its solution-to-gel transition temperature. In order to lower this temperature, the use of NaCl salt has been proposed. The new composition was characterized in order to obtain information on its thermal performance, storage stability, dose response to irradiation with a medical accelerator emitting different types of radiation, and tissue equivalence. The results obtained show an improvement in the sol-gel transition temperature and dose sensitivity compared to the composition without NaCl and broaden the knowledge of the Fricke-XO-Pluronic F-127.

Validation of the Elderly Traumatic Brain Injury Score: Observational Case Control Study.

BACKGROUND: Traumatic brain injury (TBI) poses a particular health risk for the elderly. The recently developed elderly TBI (eTBI) score combines the prognostic information of the risk factors characteristic of the geriatric population. We aimed to determine its validity and reliability on an independent sample. METHODS: We present a retrospective analysis of 506 consecutive patients after TBI aged ≥65 years. The previously described nomogram and the eTBI score were used. The primary outcome measure was mortality or vegetative state at 30 days after hospital admission. RESULTS: Mortality or vegetative state rate was 21.3%. The nomogram and eTBI Score showed similar predictive performance with accuracy of 83.8% (95% confidence interval 80.2%-87%) and 84.4% (95% confidence interval 80.8%-87.6%), respectively. On the basis of the Youden index and C4.5 algorithm, we divided patients according to the 3-tier pattern into low-, high-, and medium-risk groups. The outcome prediction in the first 2 groups was correct in 93.1% (survival in the low-risk group) and 94.4% (mortality in the high-risk group). Patients included in the medium-risk group usually required surgical treatment (85.3%) and were characterized by increased mortality or vegetative state (55%). Among patients with eTBI ≥5 (n = 221), there was no difference in outcome between those treated conservatively and surgically. CONCLUSIONS: This is the first study confirming the validity of the eTBI Score and its close association with outcome of geriatric population after TBI. The novel 3-tier risk stratification scheme was applicable to both conservatively and surgically treated patients.