Exposure to reversine affects the chondrocyte morphology and phenotype in vitro

Articular chondrocytes derived from osteoarthritic tissues (OA HAC) show a severely reduced chondrogenic commitment. This impairment undermines their use for tissue-engineered cartilage repair, which relies on cell proliferation and growth to meet therapeutic needs, but also on efficient cell plasticity to recover the chondrogenic phenotype. Reversine (Rev), a 2,6-disubstituted purine inhibitor of spindle-assembly checkpoints, was described to convert differentiated mesenchymal cells to their undifferentiated precursors. We hypothesized that Rev exposure could divert OA HAC to more plastic cells, re-boosting their subsequent commitment. HAC were enzymatically released from OA cartilage specimens, expanded for 2 weeks and treated with 5 \u3bcm Rev in dimethylsulphoxide (DMSO) or with DMSO alone for 6 days. Cell growth was assessed using the AlamarBlueTM assay. Cytoskeletal structure, endoproliferation and caspase-3-immunopositivity were assayed by epifluorescence microscopy. The OA HAC chondrogenic performance was evaluated by quantitative reverse transcription-polymerase chain reaction (RT-PCR) for glyceraldehyde-3-phosphate dehydrogenase, Sox9, Aggrecan (Agg), type II collagen (Col2), Ki67, cyclinD1, transforming growth factor-\u3b21 (TGF-\u3b21), -2 and -3, interleukin-1\u3b2 (IL-1\u3b2) and -6 , SMAD3 and -7, and vascular endothelial growth factor. Rev-treated OA HAC recovered polygonal morphology and reduced Ki67 expression and proliferation. Cell-cycle impairment accounted for altered cytoskeletal organization, endoproliferation and apoptosis, whereas a compensatory mechanism sustained the increased cyclinD1 transcript levels. Sox9, Agg and TGFs were overexpressed, but not Col2. IL transcripts were massively downregulated. These events were dose-related and transient. Overall, in spite of a higher Rev-induced transcriptional activity for extracellular matrix components and in spite of a Rev-treated cell phenotype closer to that of the three-dimensional native articular chondrocyte, Rev effects seem unleashed from a full regained chondrogenic potential

Estimation of mean number of daily hand hygiene procedures per patient can represent an effective and easy understandable method to evaluate adherence. Experience in a tertiary care pediatric hospital of Northern Italy

Introduction. Hand decontamination with alcohol-based antiseptic agents is considered  the best practise to reduce healthcare associated infections.Methods. We present a new method to monitor hand hygiene, introduced in a tertiary care pediatric hospital inNorthern Italy, which estimates the mean number of daily hand decontamination procedures performed per patient. The total amount of isopropyl alcohol and chlorhexydine solution supplied in a trimester to each hospital ward was put in relation with the number of hospitalization days, and expressed as liters/1000 hospitalization-days (World Health Organization standard), and the mean number of patients hospitalized and expressed as mean estimated number of hand hygiene procedures per patient per day (new method).Results. The two methods had  similar performance for estimating  the adherence to correct hand disinfection procedures. The new method identified wards and/or periods with high or low  adherence to the procedure and indicated where to perform interventions and their effectiveness. The new methods could result easy-to understand also for non-infection control experts.Conclusion. This method can help non-infection control experts to understand adherence to correct hand- hygiene procedures and improve quality standards

Association between Antifungal Prophylaxis and Rate of Documented Bacteremia in Febrile Neutropenic Cancer Patients

Published data have suggested a correlation between antifungal prophylaxis and bacteremia in febrile neutropenia. This correlation was investigated among 3002 febrile neutropenic patients enrolled in 4 trials during 1986-1994. Globally, 1322 patients (44%) did not receive antifungal prophylaxis; 835 (28%) received poorly absorbable antifungal agents and 845 (28%) received absorbable antifungal agents. The rates of bacteremia for these groups were 20%, 26%, and 27%, respectively (P=.0001). In a multivariate model without including antifungal prophylaxis, factors associated with bacteremia were: age, duration of hospitalization, duration of neutropenia before enrollment, underlying disease, presence of an intravenous catheter, shock, antibacterial prophylaxis, temperature, and granulocyte count at onset of fever. When antifungal prophylaxis was included, the adjustment quality of the model improved slightly (P=.05), with an odds ratio of 1.19 (95% confidence interval [CI], 0.92-1.55) for patients receiving nonabsorbable and 1.42 (95% CI, 1.07-1.88) for those who were receiving absorbable antifungal agents. Antifungal prophylaxis with absorbable agents might have an impact on the rate of documented bacteremia in febrile neutropenia. This effect should be confirmed prospectivel

Do We Really Need Quantum Mechanics to Describe Plasmonic Properties of Metal Nanostructures?

Optical properties of metal nanostructures are the basis of several scientific and technological applications. When the nanostructure characteristic size is of the order of few nm or less, it is generally accepted that only a description that explicitly describes electrons by quantum mechanics can reproduce faithfully its optical response. For example, the plasmon resonance shift upon shrinking the nanostructure size (red-shift for simple metals, blue-shift for d-metals such as gold and silver) is universally accepted to originate from the quantum nature of the system. Here we show instead that an atomistic approach based on classical physics, ωFQFμ (frequency dependent fluctuating charges and fluctuating dipoles), is able to reproduce all the typical “quantum” size effects, such as the sign and the magnitude of the plasmon shift, the progressive loss of the plasmon resonance for gold, the atomistically detailed features in the induced electron density, and the non local effects in the nanoparticle response. To support our findings, we compare the ωFQFμ results for Ag and Au with literature time-dependent DFT simulations, showing the capability of fully classical physics to reproduce these TDDFT results. Only electron tunneling between nanostructures emerges as a genuine quantum mechanical effect, that we had to include in the model by an ad hoc term

Thymosin Beta 4 may translocate from the cytoplasm in to the nucleus in HepG2 cells following serum starvation. An ultrastructural study

Due to its actin-sequestering properties, thymosin beta-4 (Tβ4) is considered to play a significant role in the cellular metabolism. Several physiological properties of Tβ4 have been reported;, however, many questions concerning its cellular function remain to be ascertained. To better understand the role of this small peptide we have analyzed by means of transmission immunoelectron microscopy techniques the ultrastructural localization of Tβ4 in HepG2 cells. Samples of HepG2 cells were fixed in a mixture of 3% formaldehyde and 0.1% glutaraldehyde in 0.1 M cacodylate buffer and processed for standard electron microscopic techniques. The samples were dehydrated in a cold graded methanol series and embedded in LR gold resin. Ultrathin sections were labeled with rabbit antibodies to Tβ4, followed by gold-labeled goat anti-rabbit, stained with uranyl acetate and bismuth subnitrate, observed and photographed in a JEOL 100S transmission electron microscope. High-resolution electron microscopy showed that Tβ4 was mainly restricted to the cytoplasm of HepG2 growing in complete medium. A strong Tβ4 reactivity was detected in the perinuclear region of the cytoplasmic compartment where gold particles appeared strictly associated to the nuclear membrane. In the nucleus specific Tβ4 labeling was observed in the nucleolus. The above electron microscopic results confirm and extend previous observations at light microscopic level, highlighting the subcellular distribution of Tβ4 in both cytoplasmic and nuclear compartments of HepG2 cells. The meaning of Tβ4 presence in the nucleolus is not on the best of our knowledge clarified yet. It could account for the interaction of Tβ4 with nucleolar actin and according with this hypothesis, Tβ4 could contribute together with the other nucleolar acting binding proteins to modulate the transcription activity of the RNA polymeras

Artificial Intelligence Models for the Detection of Microsatellite Instability from Whole-Slide Imaging of Colorectal Cancer

With the advent of whole-slide imaging (WSI), a technology that can digitally scan whole slides in high resolution, pathology is undergoing a digital revolution. Detecting microsatellite instability (MSI) in colorectal cancer is crucial for proper treatment, as it identifies patients responsible for immunotherapy. Even though universal testing for MSI is recommended, particularly in patients affected by colorectal cancer (CRC), many patients remain untested, and they reside mainly in low-income countries. A critical need exists for accessible, low-cost tools to perform MSI pre-screening. Here, the potential predictive role of the most relevant artificial intelligence-driven models in predicting microsatellite instability directly from histology alone is discussed, focusing on CRC. The role of deep learning (DL) models in identifying the MSI status is here analyzed in the most relevant studies reporting the development of algorithms trained to this end. The most important performance and the most relevant deficiencies are discussed for every AI method. The models proposed for algorithm sharing among multiple research and clinical centers, including federal learning (FL) and swarm learning (SL), are reported. According to all the studies reported here, AI models are valuable tools for predicting MSI status on WSI alone in CRC. The use of digitized H&E-stained sections and a trained algorithm allow the extraction of relevant molecular information, such as MSI status, in a short time and at a low cost. The possible advantages related to introducing DL methods in routine surgical pathology are underlined here, and the acceleration of the digital transformation of pathology departments and services is recommended

Atherosclerosis, dyslipidemia, and inflammation: the significant role of polyunsaturated fatty acids

Phospholipids play an essential role in cell membrane structure and function. The length and number of double bonds of fatty acids in membrane phospholipids are main determinants of fluidity, transport systems, activity of membrane-bound enzymes, and susceptibility to lipid peroxidation. The fatty acid profile of serum lipids, especially the phospholipids, reflects the fatty acid composition of cell membranes. Moreover, long-chain n-3 polyunsatured fatty acids decrease very-low-density lipoprotein assembly and secretion reducing triacylglycerol production. N-6 and n-3 polyunsatured fatty acids are the precursors of signalling molecules, termed “eicosanoids,” which play an important role in the regulation of inflammation. Eicosanoids derived from n-6 polyunsatured fatty acids have proinflammatory actions, while eicosanoids derived from n-3 polyunsatured fatty acids have antiinflammatory ones. Previous studies showed that inflammation contributes to both the onset and progression of atherosclerosis: actually, atherosclerosis is predominantly a chronic low-grade inflammatory disease of the vessel wall. Several studies suggested the relationship between long-chain n-3 polyunsaturated fatty acids and inflammation, showing that fatty acids may decrease endothelial activation and affect eicosanoid metabolis