[Sorting of senescent cells by flow cytometry: Specificities and pitfalls to avoid]. / Tri des cellules sénescentes par cytométrie en flux - Des spécificitéset des pièges à éviter.

Cells can be reprogrammed into senescence to adapt to a variety of stresses, most often affecting the genome integrity. Senescent cells accumulate with age or upon various insults in almost all tissues, and contribute to the development of several age-associated pathologies. Studying the molecular pathways involved in senescence induction, maintenance, or escape is challenged by the heterogeneity in the level of commitment to senescence, and by the pollution of senescent cell populations by proliferating pre- or post-senescent cells. We coped with these difficulties by developing a protocol for sorting senescent cells by flow cytometry, based on three major senescence markers : the SA-ß-Galactosidase activity, the size of the cells, and their granularity reflecting the accumulation of aggregates, lysosomes, and altered mitochondria. We address the issues related to sorting senescent cells, the pitfalls to avoid, and propose solutions for sorting viable cells expressing senescent markers at different extents.

Title: Tri des cellules sénescentes par cytométrie en flux - Des spécificitéset des pièges à éviter. Abstract: La sénescence est un état d'adaptation des cellules au stress qui contribue au vieillissement et au développement de nombreuses maladies. Étudier les voies moléculaires modulant l'induction, le maintien ou l'échappement de la sénescence est compliqué par la contamination des populations de cellules sénescentes par des cellules proliférantes pré- ou post-sénescentes. Pour contourner cette difficulté, nous avons développé un protocole de tri par cytométrie en flux, fondé sur trois marqueurs majeurs de sénescence (l'activité SA-ß-galactosidase, la taille et la granularité des cellules), qui permet de trier des cellules sénescentes viables, à des degrés choisis d'engagement dans le phénotype.

Role of astrocyte senescence regulated by the non- canonical autophagy in the neuroinflammation associated to cerebral malaria.

BACKGROUND: Cerebral malaria (CM) is a fatal neuroinflammatory syndrome caused (in humans) by the protozoa Plasmodium (P.) falciparum. Glial cell activation is one of the mechanisms that contributes to neuroinflammation in CM. RESULT: By studying a mouse model of CM (caused by P. berghei ANKA), we describe that the induction of autophagy promoted p21-dependent senescence in astrocytes and that CXCL-10 was part of the senescence-associated secretory phenotype. Furthermore, p21 expression was observed in post-mortem brain and peripheral blood samples from patients with CM. Lastly, we found that the depletion of senescent astrocytes with senolytic drugs abrogated inflammation and protected mice from CM. CONCLUSION: Our data provide evidence for a novel mechanism through which astrocytes could be involved in the neuropathophysiology of CM. p21 gene expression in blood cell and an elevated plasma CXCL-10 concentration could be valuable biomarkers of CM in humans. In the end, we believe senolytic drugs shall open up new avenues to develop newer treatment options.

Flow Cytometry-based Method for Efficient Sorting of Senescent Cells.

Cellular senescence is a reprogrammed cell state triggered as an adaptative response to a variety of stresses, most often those affecting the genome integrity. Senescent cells accumulate in most tissues with age and contribute to the development of several pathologies. Studying molecular pathways involved in senescence induction and maintenance, or in senescence escape, can be hindered by the heterogeneity of senescent cell populations. Here, we describe a flow cytometry strategy for sorting senescent cells according to three senescence canonical markers whose thresholds can be independently adapted to be more or less stringent: (i) the senescence-associated-ß-galactosidase (SA-ß-Gal) activity, detected using 5-dodecanoylaminofluorescein Di-ß-D-galactopyranoside (C12FDG), a fluorigenic substrate of ß-galactosidase; (ii) cell size, proportional to the forward scatter value, since increased size is one of the major changes observed in senescent cells; and (iii) cell granularity, proportional to the side scatter value, which reflects the accumulation of aggregates, lysosomes, and altered mitochondria in senescent cells. We applied this protocol to the sorting of normal human fibroblasts at the replicative senescence plateau. We highlighted the challenge of sorting these senescent cells because of their large sizes, and established that it requires using sorters equipped with a nozzle of an unusually large diameter: at least 200 µm. We present evidence of the sorting efficiency and sorted cell viability, as well as of the senescent nature of the sorted cells, confirmed by the detection of other senescence markers, including the expression of the CKI p21 and the presence of 53BP1 DNA damage foci. Our protocol makes it possible, for the first time, to sort senescent cells from contaminating proliferating cells and, at the same time, to sort subpopulations of senescent cells featuring senescent markers to different extents. Graphical abstract.

The NLRP6 protein is very faintly expressed in several normal and cancerous epithelial cells and may be confused with an unrelated protein.

Nod-Like Receptor Pyrin domain-containing protein 6 (NLRP6), a member of the Nucleotide-oligomerization domain-Like Receptor (NLR) family of proteins, assembles together with the ASC protein to form an inflammasome upon stimulation by bacterial lipoteichoic acid and double-stranded DNA. Besides its expression in myeloid cells, NLRP6 is also expressed in intestinal epithelial cells where it may contribute to the maintenance of gut homeostasis and negatively controls colorectal tumorigenesis. Here, we report that NLRP6 is very faintly expressed in several colon cancer cell lines, detected only in cytoplasmic small dots were it colocalizes with ASC. Consequently, it is very hardly detected by standard western-blotting techniques by several presently available commercial antibodies which, in contrast, highly cross-react with a protein of 90kDa that we demonstrate to be unrelated to NLRP6. We report here these results to caution the community not to confuse the 90kDa protein with the endogenous human NLRP6.

Life Cycle Assessment of Reusable and Disposable Cystoscopes: A Path to Greener Urological Procedures.

BACKGROUND: The environmental impact of reusable and disposable devices is unclear; reuse is expected to reduce the carbon footprint, but the environmental impact of reprocessing of reusable devices is increasingly being questioned. OBJECTIVE: The aim was to provide the first rigorous life cycle assessment of reusable and disposable flexible cystoscopes. DESIGN, SETTING, AND PARTICIPANTS: We performed a life cycle assessment of reusable flexible cystoscopes and the aS4C single-use cystoscope (aScope; Ambu, Ballerup, Denmark). For the aScope, the complete lifespan of the scope was evaluated, including raw material extraction, material formulation, component production, product assembly, distribution, transportation after use, and final disposal. For reusable cystoscopes, we limited our analysis to their reprocessing, using a model consisting of standard high-level disinfection with peracetic acid. The environmental impact was evaluated by an independent third-party consulting company APESA (Technopole Hélioparc, Pau, France) dedicated to such risk assessments. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The environmental footprint of both cystoscopes was assessed using five environmental impact categories, namely, climate change, mineral resource depletion, ecotoxicity, acidification, and eutrophication. To perform the life cycle assessment, Simapro v9.3.3 software was used and the Ecoinvent v3.5 database was employed as the primary life cycle inventory database. A Monte Carlo analysis was used to account for the inherent uncertainty in life cycle inventory data and the variability in material and energy consumption for each type of flexible cystoscope. RESULTS AND LIMITATIONS: By only comparing the disinfection reprocessing of reusable cystoscopes with the complete lifespan of the single-use cystoscope, the use of the aScope would allow a reduction of at least 33% in the climate change category, 50% in the mineral resources' depletion category, 51% in the ecotoxicity category, 71% in the acidification category, and 49% in the eutrophication category. Our results cannot be generalized to all health care facilities as we studied only one type of reprocessing method and one disposable flexible cystoscope. CONCLUSIONS: Disinfection reprocessing of reusable cystoscopes was found to have a significantly larger environmental footprint and impact than the whole lifespan of the single-use cystoscope aScope. PATIENT SUMMARY: Using a cradle-to-grave life cycle analysis, we showed that the environmental footprint of a flexible cystoscopy procedure can be reduced by using a disposable cystoscope instead of a reusable cystoscope.

Senescence Induced by UVB in Keratinocytes Impairs Amino Acids Balance.

Skin is one of the most exposed organs to external stress. Namely, UV rays are the most harmful stress that could induce important damage leading to skin aging and cancers. At the cellular level, senescence is observed in several skin cell types and contributes to skin aging. However, the origin of skin senescent cells is still unclear but is probably related to exposure to stresses. In this work, we developed an in vitro model of UVB-induced premature senescence in normal human epidermal keratinocytes. UVB-induced senescent keratinocytes display a common senescent phenotype resulting in an irreversible cell cycle arrest, an increase in the proportion of senescence-associated ß-galactosidase‒positive cells, unrepaired DNA damage, and a long-term DNA damage response activation. Moreover, UVB-induced senescent keratinocytes secrete senescence-associated secretory phenotype factors that influence cutaneous squamous cell carcinoma cell migration. Finally, a global transcriptomic study highlighted that senescent keratinocytes present a decrease in the expression of several amino acid transporters, which is associated with reduced intracellular levels of glycine, alanine, and leucine. Interestingly, the chemical inhibition of the glycine transporter SLC6A9/Glyt1 triggers senescence features.

Istradefylline protects from cisplatin-induced nephrotoxicity and peripheral neuropathy while preserving cisplatin antitumor effects.

Cisplatin is a potent chemotherapeutic drug that is widely used in the treatment of various solid cancers. However, its clinical effectiveness is strongly limited by frequent severe adverse effects, in particular nephrotoxicity and chemotherapy-induced peripheral neuropathy. Thus, there is an urgent medical need to identify novel strategies that limit cisplatin-induced toxicity. In the present study, we show that the FDA-approved adenosine A2A receptor antagonist istradefylline (KW6002) protected from cisplatin-induced nephrotoxicity and neuropathic pain in mice with or without tumors. Moreover, we also demonstrate that the antitumoral properties of cisplatin were not altered by istradefylline in tumor-bearing mice and could even be potentiated. Altogether, our results support the use of istradefylline as a valuable preventive approach for the clinical management of patients undergoing cisplatin treatment.

Cost and Environmental Impact of Disposable Flexible Cystoscopes Compared to Reusable Devices.

Objectives: To quantify the environmental impact and costs associated with flexible cystoscopy procedures from an institutional perspective, with particular attention for the comparison between disposable and reusable cystoscopes. Materials and Methods: This is a single-center retrospective study, including all flexible cystoscopies performed between 2020 and 2021 using reusable or single-use devices. The Ambu aS4C single-use cystoscope (Ballerup, Denmark) gradually replaced the reusable device in our center, with exclusive use from October 2021. Reprocessing costs for reusable cystoscopes were evaluated using a micro-costing approach. The environmental impact of reusable and disposable cystoscopes was assessed by the amount of waste and water consumed for each procedure. Results: A total of 1578 flexible cystoscopies using reusable cystoscopes were performed in 2020, and 550 cystoscopies were performed using the Ambu aS4C cystoscope from October 2021 to February 2022. The cost of flexible cystoscopy with a reusable and a disposable endoscope was €196 and €192, respectively. The amount of waste generated by reprocessing reusable and disposable cystoscopes was 800 and 200 g per procedure, respectively. Water consumption for sterilization of the reusable cystoscope was 60 L per procedure, whereas no water consumption was required with the Ambu aS4C cystoscope. A 100% Ambu aS4C cystoscope use would reduce waste generation and water consumption by 946.8 kg and 94.68 m3 per year. Conclusion: In this study, implementing a strategy of using 100% disposable cystoscopes was associated with similar costs and reduced waste generation and water consumption compared to reusable devices. Future studies are needed to compare the carbon footprint of these devices, through a comprehensive and rigorous life cycle assessment from manufacturing to recycling.

The out-of-field dose in radiation therapy induces delayed tumorigenesis by senescence evasion.

A rare but severe complication of curative-intent radiation therapy is the induction of second primary cancers. These cancers preferentially develop not inside the planning target volume (PTV) but around, over several centimeters, after a latency period of 1-40 years. We show here that normal human or mouse dermal fibroblasts submitted to the out-of-field dose scattering at the margin of a PTV receiving a mimicked patient's treatment do not die but enter in a long-lived senescent state resulting from the accumulation of unrepaired DNA single-strand breaks, in the almost absence of double-strand breaks. Importantly, a few of these senescent cells systematically and spontaneously escape from the cell cycle arrest after a while to generate daughter cells harboring mutations and invasive capacities. These findings highlight single-strand break-induced senescence as the mechanism of second primary cancer initiation, with clinically relevant spatiotemporal specificities. Senescence being pharmacologically targetable, they open the avenue for second primary cancer prevention.

Impact of insulin adsorption in various containers during hyperkalaemia treatment.

BACKGROUND: Insulin-glucose therapy in hyperkalaemia treatment has a narrow therapeutic index for a safe and efficient use. We assess the variability of the effective delivered insulin under conditions used in the setting of hyperkalaemia treatment. METHODS: A range of simulated insulin infusions was studied using different containers (bag or syringes) according to the different hyperkalaemia treatment procedures of our institution. Insulin concentration was assayed using a chromatographic method on an automatic high-performance liquid chromatography. We calculated the effective delivered insulin and compared the time average of percentage delivered insulin (TAdi) between all the procedures. RESULTS: The TAdi was significantly decreased to 63.3% of the expected insulin delivery in the polyurethane (PE) bag compared with allover container. The procedure duration and the insulin concentration influenced the variability of the insulin delivery in the PE and glass bag. The polyvinyl chloride bag had the highest TAdi at 93.8%, without significant variation during the time. TAdi reaches ∼90% of the expected insulin with all the syringe procedure without variation according to the solute used to dilute insulin. CONCLUSIONS: Clinically significant variations in intravenous insulin delivery occur in the setting of hyperkalaemia treatment according to the container. The use of propylene syringe limits the insulin delivery variation. In the future, clinical studies on hyperkalaemia treatment by insulin-glucose therapy should detail the procedure precisely.

CDKN2A/p16INK4a suppresses hepatic fatty acid oxidation through the AMPKα2-SIRT1-PPARα signaling pathway.

In addition to their well-known role in the control of cellular proliferation and cancer, cell cycle regulators are increasingly identified as important metabolic modulators. Several GWAS have identified SNPs near CDKN2A, the locus encoding for p16INK4a (p16), associated with elevated risk for cardiovascular diseases and type-2 diabetes development, two pathologies associated with impaired hepatic lipid metabolism. Although p16 was recently shown to control hepatic glucose homeostasis, it is unknown whether p16 also controls hepatic lipid metabolism. Using a combination of in vivo and in vitro approaches, we found that p16 modulates fasting-induced hepatic fatty acid oxidation (FAO) and lipid droplet accumulation. In primary hepatocytes, p16-deficiency was associated with elevated expression of genes involved in fatty acid catabolism. These transcriptional changes led to increased FAO and were associated with enhanced activation of PPARα through a mechanism requiring the catalytic AMPKα2 subunit and SIRT1, two known activators of PPARα. By contrast, p16 overexpression was associated with triglyceride accumulation and increased lipid droplet numbers in vitro, and decreased ketogenesis and hepatic mitochondrial activity in vivo Finally, gene expression analysis of liver samples from obese patients revealed a negative correlation between CDKN2A expression and PPARA and its target genes. Our findings demonstrate that p16 represses hepatic lipid catabolism during fasting and may thus participate in the preservation of metabolic flexibility.

Comparative medico-economic study of reusable vs. single-use flexible ureteroscopes.

PURPOSE: Reusable flexible-ureteroscopes (fURS) require personnel and budget for processing and repairing, whereas single-use fURS were recently developed. After exclusive reusable fURS since 2011, we experienced high repair costs and single-use fURS were therefore introduced in mid-2017. We aimed to evaluate economic and practical advantages and disadvantages of reusable versus single-use fURS. MATERIALS AND METHODS: First, we evaluated the incidence of breakage and repairs of reusable fURS in 2017. We assessed the overall operational costs of reusable fURS including purchase, processing, and repairing in our institution from 2011 to 2017. Following our experience, we created a model to compare operation costs/procedure of single-use fURS with reusable fURS depending on repair costs. RESULTS: In 2017, repair costs of reusable fURS increased by 345% compared with the period 2011-2016, causing: a median unavailability per reusable fURS of 200 days/year (100-249), median number of functioning fURS 0/5-3/5 per operating day, while unavailability of reusable fURS had become the first reason for cancellation of procedure. Since it was introduced, single-use fURS accounted for 59% of the flexible ureteroscopy activity. Taking into account the costs of processing, maintenance and repair, in 2011-2016 versus 2017, the single-use fURS was cost-effective compared with the reusable fURS until the 22nd procedure versus the 73rd procedure, respectively. CONCLUSIONS: After years of exclusive reusable fURS, the rising incidence of breakage not only increased maintenance costs but also hampered daily activity owing to unavailability of the devices. The introduction of single-use with reusable fURS provided substantial help to maintain our activity.

Effect of the new high vacuum technology on the chemical composition of maple sap and syrup.

BACKGROUND: Techniques used to produce maple syrup have considerably evolved over the last decades making them more efficient and economically profitable. However, these advances must respect composition and quality standards as well as authenticity of maple products. Recently, a new and improved high vacuum technology has been made available to producers to achieve higher sap yields. The aim of the present study was therefore to evaluate the effect of this new system on the yield of sap and on the sap and syrup chemical composition. RESULTS: Sap yield was monitored during the 2013 and 2014 seasons for high vacuum collection systems (25-28 InHg) and compared to the control systems (20 InHg). Samples of sap and syrup were also collected for chemical analysis. During the 2013 season, a sap volume of 166.19 L/tap was recorded at 25 InHg vacuum level while the control vacuum level permitted to collect 139.47 L/tap, corresponding to a yield increase of 19.2 %. The following season, a yield increase of 38.2 % was measured when control and 28 InHg vacuum levels were compared with 118.06 and 163.13 L/tap, respectively. Results on the pH, color, flavor, minerals, sugars, organic acids, total polyphenols, total nitrogen, abscisic acid and auxin (Indol-3-acetic acid) showed no major differences between high vacuum technology and the control with values remaining within ranges previously published. CONCLUSION: Results showed that a use of high vacuum systems increased sap yield and had no major impact on the quality and purity of maple sap and syrups compared with the control systems.

Characterization and Removal of Buddy Off-Flavor in Maple Syrup.

Buddy maple syrup is characterized by an unpleasant cabbage-like flavor occurring generally toward the end of the sap harvest season. Occurrence of buddy off-flavor leads to a decrease in syrup value and economic loss for the industry. It is therefore relevant to characterize the off-flavor in order to apply corrective treatments. HS-SPME combined with GC/MS was applied to analyze volatile aroma compounds in buddy maple syrup samples. Two novel volatile sulfur compounds were found in maple syrup: dimethyl disulfide (DMDS) and dimethyl trisulfide. A 3-alternative forced choice in ascending concentration of different buddy syrups diluted in good quality syrup was conducted in triplicate to assess buddy syrup concentration thresholds leading to detection and recognition of the off-flavor by 16 panelists while monitoring volatile aroma compounds in diluted samples. Results showed that DMDS was associated with the flavor defect. The recognition threshold concentration of buddy syrup varies depending on the syrup sample and the off-flavor can be detected in syrups containing very low DMDS content. Application of a continuous heat treatment on buddy syrups for 2 hr at 104.5 °C led to a removal of the buddy off-flavor as well as a significant reduction in DMDS content. PRACTICAL APPLICATION: The results of this study provide a better understanding of the buddy off-flavor in maple syrup and the heat treatment applied allowed us to eliminate this defect and obtain a syrup with a better sensory quality.

Bone Augmentation and Simultaneous Implant Placement with Allogenic Bone Rings and Analysis of Its Purification Success.

The main objective of this manuscript was to demonstrate the use of freeze-dried bone allografts (FDBA) by means of a technique of simultaneous bone augmentation and implant placement ("Bone Ring Technique") in different indications, i.e., ridge reconstruction and sinus floor elevation procedure with a maxillary bone height of less than 4 mm. Moreover, cases with an up to 3-year follow-up were chosen to analyze the techniques of mid-term clinical success. Finally, the purification success of the FDBA was analyzed by means of established scanning electron microscopic (SEM) and histological methods. The FBDA bone ring was applied in three different patients and indications and presented; the healing success was analyzed on the basis of radiographical and clinical images. For analysis of the purification of the allogeneic bone, previously established histological methods and scanning electron microscopy (SEM) were applied. All analyzed patient cases showed that the FDBA-based bone ring was fully integrated into newly built alveolar bone. Furthermore, the observations revealed that the three-dimensional bone reconstructions in maxilla and mandible were stable within the observational period of up to 3 years. Altogether, the present data show that the application of the Bone Ring Technique using the FDBA rings allows for successful regeneration of alveolar bone with a predictable clinical outcome, functionality and esthetics. Moreover, the material analyses showed that the allogeneic bone tissue was free of cells or cell remnants, while the (ultra-) structure of the bone matrix has been retained. Thus, the biological safety of the FDBA has been confirmed.

Consumption rituals relating to food and drink: A review and research agenda.

Rituals are common in relation to consumption of food and drink, and are related to psychosocial benefits such as social bonding, affective change, and enhanced consumer perceptions. However, theoretical understanding of food and drink consumption rituals, and empirical examination of their effects and mechanisms of action, is limited. In this literature review we show a need for greater theoretical understanding of these rituals, and especially mechanisms linking ritual performance to outcomes. Such understanding would be greatly enhanced by a holistic model of consumption ritual and the development of an instrument that can be used to study different aspects of such rituals, both of which are currently lacking. We also highlight specific research questions regarding the cognitive, social, and affective outcomes of ritual consumption of food and drink, and the affective and cognitive-behavioural mechanisms that might precede them. We provide suggestions regarding the research paradigms and methods that might suit such questions, and encourage research along these lines of inquiry.

A systems biology approach to explore the impact of maple tree dormancy release on sap variation and maple syrup quality.

Maple sap is a complex nutrient matrix collected during spring to produce maple syrup. The characteristics of sap change over the production period and its composition directly impacts syrup quality. This variability could in part be attributed to changes in tree metabolism following dormancy release, but little is known about these changes in deciduous trees. Therefore, understanding the variation in sap composition associated with dormancy release could help pinpoint the causes of some defects in maple syrup. In particular, a defect known as "buddy", is an increasing concern for the industry. This off-flavor appears around the time of bud break, hence its name. To investigate sap variation related to bud break and the buddy defect, we monitored sap variation with respect to a dormancy release index (Sbb) and syrup quality. First, we looked at variation in amino acid content during this period. We observed a shift in amino acid relative proportions associated with dormancy release and found that most of them increase rapidly near the point of bud break, correlating with changes in syrup quality. Second, we identified biological processes that respond to variation in maple sap by performing a competition assay using the barcoded Saccharomyces cerevisiae prototroph deletion collection. This untargeted approach revealed that the organic sulfur content may be responsible for the development of the buddy off-flavor, and that dormancy release is necessary for the appearance of the defect, but other factors such as microbial activity may also be contributing.

Right Sizing: Sensory-Based Product Design Is a Promising Strategy to Nudge Consumers toward Healthier Portions.

Research has shown that people consume more food when offered larger portions, and that reducing exposure to large food portions and packages could decrease the average daily energy consumed. In this context, our aim is to develop strategies to promote healthier eating behaviors by reducing portion selection and intake. The present research investigates the impact of different visual attributes of foods on quantity perception and portion selection. In the first study, we tested whether modifying the shape of a familiar food influenced the ideal portion size in adults. In the second study, we assessed the impact of shape, number of units, size, and color variety on a perceived quantity for a familiar multiunit product in children. Participants (N1 = 70 adults, N2 = 62 children) completed different picture-based computer tasks. As hypothesized: (1) adults selected a smaller ideal portion size for an elongated product than for wider and thicker shapes, and (2) children's perception of food quantity was primarily driven by number of pieces, with smaller effects of size and elongation. Perceived quantity was not influenced by color variety. These findings suggest that it may be possible to reduce the size of food portions without negatively impacting perceived quantity, and to provide opportunities to nudge consumers towards smaller portions while maintaining satisfaction.

Pre-malignant transformation by senescence evasion is prevented by the PERK and ATF6alpha branches of the Unfolded Protein Response.

The incidence of carcinomas highly increases with age. However, the initial steps of the age-related molecular carcinogenic processes remain poorly characterized. We previously showed that normal human epidermal keratinocytes spontaneously and systematically escape from senescence to give rise to preneoplastic emerging cells through a process called post-senescence neoplastic emergence (PSNE). To identify molecular pathways involved in the switch from senescence to pre-transformation, we performed Connectivity Map analyses and DAVID functional annotations followed by hierarchical clustering and multidimensional scaling of the gene expression signature of PSNE cells. We identified endoplasmic reticulum stress related pathways as key regulators of PSNE. Invalidation by RNA interference of the UPR sensors PERK, ATF6α, but not IRE1α, delayed the occurrence of senescence when performed in pre-senescent cells, and increased the PSNE frequency when performed in already senescent cells. Conversely, endoplasmic reticulum stress inducers applied to already senescent cells decreased the frequency of PSNE. In conclusion, these results indicate that the activation of the UPR could protect from the early carcinogenic steps by senescence evasion. This opens new avenues to explore therapeutics that could be useful in decreasing the age-associated tumor incidence.

Vertical bone augmentation in a single-tooth gap with an allogenic bone ring: Clinical considerations.

OBJECTIVE: The main objective of this case report is to introduce a one-stage bone block augmentation with a cylindrical freeze-dried bone allograft (FDBA) and simultaneous implantation for the reconstruction of a single-tooth bone defect. CLINICAL CONSIDERATIONS: The report describes this method on the basis of radiographical and clinical images derived from a single patient. CONCLUSIONS: The report demonstrates the time-saving and successful application of this treatment concept, which has the potential to increase patient satisfaction and comfort. CLINICAL SIGNIFICANCE: The application of the presented technique enabled a prosthetic rehabilitation of the extracted tooth about 3 months earlier as compared to the conventional procedure, while demonstrating no compromises regarding clinical outcome, functionality and esthetics.