Successful BK virus-specific T cell therapy in a kidney transplant recipient with progressive multifocal leukoencephalopathy.

The strategy for progressive multifocal leukoencephalopathy (PML) in solid organ transplant recipients primarily focuses on reducing immunosuppressive therapy. However, this approach offers limited efficacy and carries a high risk of graft loss. Here, we present the case of a 64-year-old male kidney transplant recipient with a high degree of immunosuppression who developed PML in October 2022. Despite the standard reduction of immunosuppressive therapy, the patient's condition continued to deteriorate, as evidenced by worsening neurological symptoms and increasing JC virus (JCV) DNA levels in cerebrospinal fluid. This prompted the innovative use of BKPyV-virus-specific T cell (BKPyV-VST) therapy, given the genetic similarities between BK and JCVs. Infusion of third-party donor BKPyV-VST resulted in clinical stabilization, a significant reduction in JCV-DNA levels, and the emergence of a JCV-specific T cell response, as observed in enzyme-linked immunospot assays and TCRß sequencing. This represents the first case report of successful third-party BKPyV-VST therapy in a kidney recipient presenting PML, without graft-versus-host disease or graft dysfunction.

Clinical protocol phase II study of tumor infiltrating lymphocytes in advanced tumors with alterations in the SWI/SNF complex: the TILTS study.

The SWI/SNF complex is a chromatin remodeling complex comprised by several proteins such as SMARCA4 or SMARCB1. Mutations in its components can lead to the development of aggressive rhabdoid tumors such as epithelioid sarcoma, malignant rhabdoid tumor or small cell carcinoma of the ovary hypercalcemic type, among others. These malignancies tend to affect young patients and their prognosis is poor given the lack of effective treatments. Characteristically, these tumors are highly infiltrated by TILs, suggesting that some lymphocytes are recognizing tumor antigens. The use of those TILs as a therapeutic strategy is a promising approach worth exploring. Here, we report the clinical protocol of the TILTS study, a Phase II clinical trial assessing personalized adoptive cell therapy with TILs in patients affected by these tumor types.Clinical Trial Registration: 2023-504632-17-00 (www.clinicaltrialsregister.eu) (ClinicalTrials.gov).

[Box: see text].

Fracture load of chairside CAD-CAM veneers fabricated with pre-and fully crystalized lithium disilicate ceramics.

PURPOSE: To evaluate the fracture load of chairside computer-aided design and computer-aided manufacturing (CAD-CAM) veneers fabricated with two conventional pre-crystallized and two fully crystallized lithium disilicate ceramic materials. MATERIALS AND METHODS: Seventy-five chairside CAD-CAM veneers (15 specimens/group) for maxillary right central incisors were fabricated with different lithium disilicate brands: (1) IPS e.max CAD; (2) Amber Mill; (3) Cerec Tessera; (4) n!ce Straumann; and (5) GC Initial LiSi Block. Restorations were cemented with resin luting cement (Variolink Esthetic, Ivoclar) to 3D-printed resin dies. Bonded restorations received 5000 thermal cycles and then were loaded until fracture. Statistical analysis included One-Way ANOVA. RESULTS: Conventional pre-crystallized e.max CAD displayed the highest fracture load value (640 N), followed by fully-crystallized n!ce Straumann (547 N), pre-crystallized Cerec Tessera (503 N), pre-crystallized Amber Mill (476 N), respectively; fully-crystallized GC Initial LiSi Block (431 N) displayed the lowest values. When comparing the fracture load of recent lithium disilicate ceramic material to the e.max group, which acted as the control, significant differences were noted. The LiSi Block GC group, in particular, had considerably higher mean difference values (208.867, p < 0.001, 95% CI [89.63, 328.10]), as did the Amber Mill group (164.200, p = 0.002, 95% CI [44.96, 283.44]) and CEREC Tessera group (137.533, p = 0.016, 95% CI [18.30, 256.77]). The e.max and n!ce Straumann groups had no statistically significant differences in mean scores (92.933, p = 0.198, 95% CI [-26.30, 212.17]). These findings imply that the clinical performance of recent lithium disilicate veneers varies when compared to the e.max CAD group. CONCLUSIONS: The fracture load of chairside CAD-CAM lithium disilicate veneers for maxillary central incisors varies according to the type of ceramic brands. Conventional pre-crystallized e.max CAD displayed higher fracture load than the recent pre- and fully-crystallized lithium disilicate materials, emphasizing the significance of choosing the right product based on the desired clinical outcome.

Comparability exercise of critical quality attributes of clinical-grade human mesenchymal stromal cells from the Wharton's jelly: single-use stirred tank bioreactors versus planar culture systems.

BACKGROUND AIMS: The increasing demand of clinical-grade mesenchymal stromal cells (MSCs) for use in advanced therapy medicinal products (ATMPs) require a re-evaluation of manufacturing strategies, ensuring scalability from two-dimensional (2D) surfaces to volumetric (3D) productivities. Herein we describe the design and validation of a Good Manufacturing Practice-compliant 3D culture methodology using microcarriers and 3-L single-use stirred tank bioreactors (STRs) for the expansion of Wharton's jelly (WJ)-derived MSCs in accordance to current regulatory and quality requirements. METHODS: MSC,WJ were successfully expanded in 3D and final product characterization was in conformity with Critical Quality Attributes and product specifications previously established for 2D expansion conditions. RESULTS: After 6 days of culture, cell yields in the final product from the 3D cultures (mean 9.48 × 108 ± 1.07 × 107 cells) were slightly lower but comparable with those obtained from 2D surfaces (mean 9.73 × 108 ± 2.36 × 108 cells) after 8 days. In all analyzed batches, viability was >90%. Immunophenotype of MSC,WJ was highly positive for CD90 and CD73 markers and lacked of expression of CD31, CD45 and HLA-DR. Compared with 2D expansions, CD105 was detected at lower levels in 3D cultures due to the harvesting procedure from microcarriers involving trypsin at high concentration, and this had no impact on multipotency. Cells presented normal karyotype and strong immunomodulatory potential in vitro. Sterility, Mycoplasma, endotoxin and adventitious virus were negative in both batches produced. CONCLUSIONS: In summary, we demonstrated the establishment of a feasible and reproducible 3D bioprocess using single-use STR for clinical-grade MSC,WJ production and provide evidence supporting comparability of 3D versus 2D production strategies. This comparability exercise evaluates the direct implementation of using single-use STR for the scale-up production of MSC,WJ and, by extension, other cell types intended for allogeneic therapies.

Clinical translation of mesenchymal stromal cell extracellular vesicles: Considerations on scientific rationale and production requisites.

The present paper is a commentary to 'Identification and characterization of hADSC-derived exosome proteins from different isolation methods' (Huang et al. 2021; 10.1111/jcmm.16775). Given the enthusiasm for the potential of mesenchymal stromal cell-derived extracellular vesicles (MSC-EVs), some considerations deserve attention as they move through successive stages of research and application into humans. We herein remark the prerequisite of generating that evidence ensuring a high consistency in safety, composition and biological activity of the intended MSC-EV preparations, and the suitability of disparate isolation techniques to produce efficacious EV preparations and fulfil requirements for standardized clinical-grade biomanufacturing.

Development of Proanthocyanidin-Loaded Mesoporous Silica Nanoparticles for Improving Dental Adhesion.

Dentin biomodification is a promising approach to enhance dental tissue biomechanics and biostability for restorative and reparative therapies. One of the most active dentin tissue biomodifiers is proanthocyanidin (PAC)-rich natural extracts, which are used in the dental bonding procedure in combination with resin-based adhesives (RBAs). This study aimed to investigate the use of mesoporous silica nanoparticles (MSNs) for the sustained delivery of PACs for dentin biomodification as a novel drug-delivery system for dental applications. The effects of the incorporation of MSN functionalized with 3-aminopropyltriethoxysilane (APTES) and loaded with PAC into an experimental RBA were assessed by characterizing the material mechanical properties. In addition, the immediate and long-term bonding performance of an experimental resin-based primer (RBP) containing MSN-APTES loaded with PAC was also evaluated. For that, different formulations of RBA and RBP were prepared containing 20% w/v MSN-APTES loaded with PAC before or after functionalization (MSN-PAC-APTES and MSN-APTES-PAC, respectively). The incorporation of MSN-APTES-PAC did not negatively impact the degree of conversion or the overall mechanical properties of the RBA. However, adding MSN-PAC-APTES resulted in inferior mechanical properties of the experimental RBA. In the adhesion studies, APTES-functionalized MSN was successfully added to an experimental RBP for drug-delivery purposes without compromising the bond strength to the dentin or the failure mode. Interestingly, the sequence of surface functionalization with APTES resulted in differences in the bonding performance, with better long-term results for RBP containing MSN loaded with PAC after functionalization.

Improved short-term outcomes of kidney transplants in controlled donation after the circulatory determination of death with the use of normothermic regional perfusion.

Normothermic regional perfusion (NRP) allows the in situ perfusion of organs with oxygenated blood in donation after the circulatory determination of death (DCDD). We aimed at evaluating the impact of NRP on the short-term outcomes of kidney transplants in controlled DCDD (cDCDD). This is a multicenter, nationwide, retrospective study comparing cDCDD kidneys obtained with NRP versus the standard rapid recovery (RR) technique. During 2012-2018, 2302 cDCDD adult kidney transplants were performed in Spain using NRP (n = 865) or RR (n = 1437). The study groups differed in donor and recipient age, warm, and cold ischemic time and use of ex situ machine perfusion. Transplants in the NRP group were more frequently performed in high-volume centers (≥90 transplants/year). Through matching by propensity score, two cohorts with a total of 770 patients were obtained. After the matching, no statistically significant differences were observed between the groups in terms of primary nonfunction (p = .261) and mortality at 1 year (p =  .111). However, the RR of kidneys was associated with a significantly increased odds of delayed graft function (OR 1.97 [95% CI 1.43-2.72]; p < .001) and 1-year graft loss (OR 1.77 [95% CI 1.01-3.17]; p = .034). In conclusion, compared with RR, NRP appears to improve the short-term outcomes of cDCDD kidney transplants.

Unmasking Retinitis Pigmentosa complex cases by a whole genome sequencing algorithm based on open-access tools: hidden recessive inheritance and potential oligogenic variants.

BACKGROUND: Retinitis Pigmentosa (RP) is a clinically and genetically heterogeneous disorder that results in inherited blindness. Despite the large number of genes identified, only ~ 60% of cases receive a genetic diagnosis using targeted-sequencing. The aim of this study was to design a whole genome sequencing (WGS) based approach to increase the diagnostic yield of complex Retinitis Pigmentosa cases. METHODS: WGS was conducted in three family members, belonging to one large apparent autosomal dominant RP family that remained unsolved by previous studies, using Illumina TruSeq library preparation kit and Illumina HiSeq X platform. Variant annotation, filtering and prioritization were performed using a number of open-access tools and public databases. Sanger sequencing of candidate variants was conducted in the extended family members. RESULTS: We have developed and optimized an algorithm, based on the combination of different open-access tools, for variant prioritization of WGS data which allowed us to reduce significantly the number of likely causative variants pending to be manually assessed and segregated. Following this algorithm, four heterozygous variants in one autosomal recessive gene (USH2A) were identified, segregating in pairs in the affected members. Additionally, two pathogenic alleles in ADGRV1 and PDZD7 could be contributing to the phenotype in one patient. CONCLUSIONS: The optimization of a diagnostic algorithm for WGS data analysis, accompanied by a hypothesis-free approach, have allowed us to unmask the genetic cause of the disease in one large RP family, as well as to reassign its inheritance pattern which implies differences in the clinical management of these cases. These results contribute to increasing the number of cases with apparently dominant inheritance that carry causal mutations in recessive genes, as well as the possible involvement of various genes in the pathogenesis of RP in one patient. Moreover, our WGS-analysis approach, based on open-access tools, can easily be implemented by other researchers and clinicians to improve the diagnostic yield of additional patients with inherited retinal dystrophies.

Application of BMP-2/FGF-2 gene-activated scaffolds for dental pulp capping.

OBJECTIVES: To evaluate the effect of non-viral gene therapy on human dental pulp stem cells (DPSCs) in an in vitro and an ex vivo model. MATERIALS AND METHODS: Nanoplexes comprising polyethyleneimine (PEI) and plasmid DNA (pDNA) encoding for fibroblast growth factor-2 (pFGF-2) and bone morphogenic protein-2 (pBMP-2) were cultured with DPSCs to evaluate cytotoxicity, protein expression, and mineralization activity. Collagen scaffolds loaded with these nanoplexes or mineral trioxide aggregate (MTA) were utilized in an ex vivo tooth culture model to assess pulp response, over a period of 14 days. All nanoplex formulations were characterized for size and zeta potential by measuring dynamic light scattering and electrophoretic mobility, respectively. RESULTS: DPSCs treated with the nanoplexes showed increased cell proliferation and enhanced expression of BMP-2 and FGF-2 proteins. Collagen scaffolds containing PEI-pBMP-2 and/or pFGF-2 nanoplexes significantly increased cell proliferation, BMP-2 and FGF-2 expression, and mineralization when compared to MTA. Ex vivo histology showed a well-preserved pulp and healthy tissue in both the MTA and scaffold groups. Connective tissue in contact with the scaffold was dense and homogeneous, with some cells present in contact and within the scaffold. CONCLUSION: Transfection of DPSCs with pBMP-2/pFGF-2 nanoplexes resulted in increased expression of BMP-2 and FGF-2, enhanced proliferation, and mineralization properties compared to MTA. These findings were supported by the ex vivo observations. CLINICAL RELEVANCE: This biological approach in pulp capping brings new insights into the effective management of engineered pulp tissues, mainly those generated by the transplantation of DPSCs in empty root canals.

A Multi-Strategy Sequencing Workflow in Inherited Retinal Dystrophies: Routine Diagnosis, Addressing Unsolved Cases and Candidate Genes Identification.

The management of unsolved inherited retinal dystrophies (IRD) cases is challenging since no standard pipelines have been established. This study aimed to define a diagnostic algorithm useful for the diagnostic routine and to address unsolved cases. Here, we applied a Next-Generation Sequencing-based workflow, including a first step of panel sequencing (PS) followed by clinical-exome sequencing (CES) and whole-exome sequencing (WES), in 46 IRD patients belonging to 42 families. Twenty-six likely causal variants in retinal genes were found by PS and CES. CES and WES allowed proposing two novel candidate loci (WDFY3 and a X-linked region including CITED1), both abundantly expressed in human retina according to RT-PCR and immunohistochemistry. After comparison studies, PS showed the best quality and cost values, CES and WES involved similar analytical efforts and WES presented the highest diagnostic yield. These results reinforce the relevance of panels as a first step in the diagnostic routine and suggest WES as the next strategy for unsolved cases, reserving CES for the simultaneous study of multiple conditions. Standardizing this algorithm would enhance the efficiency and equity of clinical genetics practice. Furthermore, the identified candidate genes could contribute to increase the diagnostic yield and expand the mutational spectrum in these disorders.

[Prevalence of smoking among Chilean older people]. / Tabaquismo en el adulto mayor: un freno al envejecimiento saludable en la población chilena.

BACKGROUND: Smoking is one of the main causes of death among adults worldwide. AIM: To characterize smoking among Chilean older people, according to sociodemographic and clinical variables. MATERIAL AND METHODS: Secondary analysis of data obtained during the National Health Survey 2009-10, selecting individuals aged 60 years and older. Expansion factors were used due to the complex design of the sample. Prevalence and characteristics of smoking were calculated, according to age, sex, educational level, marital status, healthcare insurance system and comorbidities. RESULTS: Nineteen percent of older people were actual smokers, and 85% of these smokers were aged between 60 and 69 years. Forty-five percent were highly dependent to nicotine and 73% reported their intention to quit smoking. CONCLUSIONS: There is a high prevalence of tobacco smoking among Chilean older people. Prevention measures are needed.

Kidney transplantation from donors after uncontrolled circulatory death: the Spanish experience.

Donation after uncontrolled circulatory death (uDCD) refers to donation from persons who have died following cardiac arrest and unsuccessful attempt at resuscitation. We report the Spanish experience of uDCD kidney transplantation, and identify factors related to short-term post-transplant outcomes. The Spanish CORE system compiles data on all donation and transplant procedures in the country. Between 2012-2015, 517 kidney transplants from 288 uDCD donors were performed. The incidence of primary non-function was 10%, and the incidence of delayed graft function was 76%. One-year death-censored graft survival was 87%. In a Cox-Model, donor age ≥ 60 years (odds ratio [OR] 2.7; 95% confidence interval [CI] 1.2-6.1), in situ cooling of kidneys versus normothermic regional perfusion (OR 5.6; 95% CI 2.7-11.5) or hypothermic regional perfusion based on the use of extracorporeal membrane oxygenation devices (OR 4.3; 95% CI 2.1-8.6), and a recipient history of prior kidney transplant (OR 3.5; 95% CI 1.5-8.3) all significantly increased the risk of graft loss during the first year after transplantation. Kidney transplantation from uDCD donors provides acceptable 1-year outcomes, although there is room for improvement. Hypothermic and normothermic regional perfusion strategies are preferable to in situ cooling of kidneys from uDCD donors.

Structural and biomechanical changes to dentin extracellular matrix following chemical removal of proteoglycans.

Proteoglycans are biomacromolecules with significant biomineralization and structural roles in the dentin extracellular matrix. This study comprehensively assessed the mechanical properties and morphology of the dentin extracellular matrix following chemical removal of proteoglycans to elucidate the structural roles of proteoglycans in dentin. Dentin extracellular matrix was prepared from extracted teeth after complete tissue demineralization. Chemical removal of proteoglycans was carried-out using guanidine hydrochloride for up to 10 days. The removal of proteoglycans was determined by dimethylmethylene blue colorimetric assay and histological staining analyses using transmission electron microscopy and optical microscopy. The modulus of elasticity of dentin matrix was determined by a 3-point bending test method. Partial removal of proteoglycans induced significant modifications to the dentin matrix, particularly to type I collagen. Removal of proteoglycans significantly decreased the modulus of elasticity of dentin extracellular matrix (p < 0.0001). In conclusion, the subtle disruption of proteoglycans induces pronounced changes to the collagen network packing and the bulk modulus of elasticity of dentin matrix.

Sodium Trimetaphosphate as a Novel Strategy for Matrix Metalloproteinase Inhibition and Dentin Remineralization.

The effect of sodium trimetaphosphate (STMP) as an antiproteolytic and remineralizing agent on demineralized dentin was evaluated in vitro. The inhibitory potential of STMP at 0.5, 1.5, 3.5, and 5% against recombinant matrix metalloproteinases (MMPs) MMPs-2 and -9 was assessed by zymography. To investigate its remineralization potential, 40 bovine root specimens were obtained and subjected to a demineralization protocol to produce caries-like dentin lesions. After that, dentin surfaces were divided into 3 areas: (1) mineralized (no treatment); (2) demineralized; and (3) demineralized/treated with STMP and submitted to a pH-cycling associated or not with STMP (1.5, 3.5, or 5% STMP, 10 min of treatment). After that, superficial hardness (SH) and cross-sectional hardness (CSH) were determined. Polarized light microscopy (PLM) was used to qualitatively evaluate mineralization within the caries-like lesions. The zymographic analysis showed that STMP solution is a potent inhibitor of the gelatinolytic activity of MMPs-2 and -9 depending on the dose, since the lowest concentration (0.5%) partially inhibited the enzyme activity, while the higher concentrations completely inhibited enzyme activity. Regarding remineralization effect, only 1.5% STMP solution enhanced both the SH and CSH. PLM showed that the area treated with 1.5% STMP presented similar birefringence as mineralized sound dentin. In conclusion, 1.5% STMP solution is effective as an antiproteolytic agent against MMPs and promotes dentin remineralization.

Extracellular vesicles do not contribute to higher circulating levels of soluble LRP1 in idiopathic dilated cardiomyopathy.

Idiopathic dilated cardiomyopathy (IDCM) is a frequent cause of heart transplantation. Potentially valuable blood markers are being sought, and low-density lipoprotein receptor-related protein 1 (LRP1) has been linked to the underlying molecular basis of the disease. This study compared circulating levels of soluble LRP1 (sLRP1) in IDCM patients and healthy controls and elucidated whether sLRP1 is exported out of the myocardium through extracellular vesicles (EVs) to gain a better understanding of the pathogenesis of the disease. LRP1 α chain expression was analysed in samples collected from the left ventricles of explanted hearts using immunohistochemistry. sLRP1 concentrations were determined in platelet-free plasma by enzyme-linked immunosorbent assay. Plasma-derived EVs were extracted by size-exclusion chromatography (SEC) and characterized by nanoparticle tracking analysis and cryo-transmission electron microscopy. The distributions of vesicular (CD9, CD81) and myocardial (caveolin-3) proteins and LRP1 α chain were assessed in SEC fractions by flow cytometry. LRP1 α chain was preferably localized to blood vessels in IDCM compared to control myocardium. Circulating sLRP1 was increased in IDCM patients. CD9- and CD81-positive fractions enriched with membrane vesicles with the expected size and morphology were isolated from both groups. The LRP1 α chain was not present in these SEC fractions, which were also positive for caveolin-3. The increase in circulating sLRP1 in IDCM patients may be clinically valuable. Although EVs do not contribute to higher sLRP1 levels in IDCM, a comprehensive analysis of EV content would provide further insights into the search for novel blood markers.

267 Spanish Exomes Reveal Population-Specific Differences in Disease-Related Genetic Variation.

Recent results from large-scale genomic projects suggest that allele frequencies, which are highly relevant for medical purposes, differ considerably across different populations. The need for a detailed catalog of local variability motivated the whole-exome sequencing of 267 unrelated individuals, representative of the healthy Spanish population. Like in other studies, a considerable number of rare variants were found (almost one-third of the described variants). There were also relevant differences in allelic frequencies in polymorphic variants, including ∼10,000 polymorphisms private to the Spanish population. The allelic frequencies of variants conferring susceptibility to complex diseases (including cancer, schizophrenia, Alzheimer disease, type 2 diabetes, and other pathologies) were overall similar to those of other populations. However, the trend is the opposite for variants linked to Mendelian and rare diseases (including several retinal degenerative dystrophies and cardiomyopathies) that show marked frequency differences between populations. Interestingly, a correspondence between differences in allelic frequencies and disease prevalence was found, highlighting the relevance of frequency differences in disease risk. These differences are also observed in variants that disrupt known drug binding sites, suggesting an important role for local variability in population-specific drug resistances or adverse effects. We have made the Spanish population variant server web page that contains population frequency information for the complete list of 170,888 variant positions we found publicly available (http://spv.babelomics.org/), We show that it if fundamental to determine population-specific variant frequencies to distinguish real disease associations from population-specific polymorphisms.

Absolute Configuration of Native Oligomeric Proanthocyanidins with Dentin Biomodification Potency.

The structurally complex oligomeric proanthocyanidins (OPACs) are promising biomimetic agents, capable of strengthening the macromolecular backbone of teeth via intermolecular and intermicrofibrillar cross-linking. This study establishes analytical methods capable of determining the absolute configuration of the catechin-type monomeric units of underivatized OPACs. This preserves the capacity of their biological evaluation, aimed at understanding the inevitably stereospecific interactions between the OPACs and dentin collagen. Guided by dental bioassays (modulus of elasticity, long-term stability), two new trimeric and tetrameric A-type OPACs were discovered as dentin biomodifiers from pine (Pinus massoniana) bark: epicatechin-(2ß→O→7,4ß→8)-epicatechin-(2ß→O→7,4ß→8)-catechin (5) and epicatechin-(2ß→O→7,4ß→8)-epicatechin-(2ß→O→7,4ß→6)-epicatechin-(2ß→O→7,4ß→8)-catechin (6), respectively. Combining 1D/2D NMR, HRESIMS, ECD, 1H iterative full spin analysis (HiFSA), and gauge-invariant atomic orbital (GIAO) δ calculations, we demonstrate how 13C NMR chemical shifts (diastereomeric building blocks (A-type dimers)) empower the determination of the absolute configuration of monomeric units in the higher oligomers 5 and 6. Collectively, NMR with ECD reference data elevates the level of structural information achievable for these structurally demanding molecules when degradation analysis is to be avoided. Considering their numerous and deceptively subtle, but 3D impactful, structural variations, this advances the probing of OPAC chemical spaces for species that bind selectively to collagenous and potentially other biologically important biomacromolecules.

Wrap53, a natural p53 antisense transcript required for p53 induction upon DNA damage.

Antisense transcription is a widespread phenomenon in the mammalian genome. It is thought to play a role in regulation of gene expression, but its exact functional significance is largely unknown. We have identified a natural antisense transcript of p53, designated Wrap53, that regulates endogenous p53 mRNA levels and further induction of p53 protein by targeting the 5' untranslated region of p53 mRNA. siRNA knockdown of Wrap53 results in significant decrease in p53 mRNA and suppression of p53 induction upon DNA damage. Conversely, overexpression of Wrap53 increases p53 mRNA and protein levels. Blocking of potential Wrap53/p53 RNA hybrids reduces p53 levels nearly as efficiently as Wrap53 knockdown, strongly suggesting that Wrap53 regulates p53 via Wrap53/p53 RNA interaction. Furthermore, induction of Wrap53 sensitizes cells for p53-dependent apoptosis. This discovery not only reveals a regulatory pathway for controlling p53, but also proposes a general mechanism for antisense-mediated gene regulation in human cells.

Effect of synthetic and natural-derived novel endodontic irrigant solutions on mechanical properties of human dentin.

This study aimed to evaluate the effects of different synthetic and natural-derived root canal irrigants (6% sodium hypochlorite [NaOCl], 6% calcium hypochlorite [Ca(OCl)2] and 6.5% grape seed extract [GSE]) on dentin mechanical properties (flexural strength, ultimate tensile strength [UTS] and fracture resistance). Rectangular-shaped beams and hourglass-shaped sections obtained from mid-coronal and root dentin were treated with 6% NaOCl, 6% Ca(OCl)2 or 6.5% GSE for 30 min. The irrigant solutions were replaced every 5 min. Then, the dentin specimens were rinsed with distilled water (DW) followed by incubation with 17% EDTA for 1 min, and thoroughly rinsed with DW again. Specimens from the control group were tested without prior irrigation. After treatment with the irrigants, dentin beams were used to assess the flexural strength (n = 10) while UTS was evaluated using the root dentin hourglass-shaped sections (n = 10). Similarly, roots with 1 mm of dentinal wall thickness were obtained from human teeth and treated with the same irrigant solutions (n = 10). A compressive loading was applied to the coronal surfaces of roots until fracture. The values of each mechanical test were statistically analyzed individually by one-way ANOVA followed by Tukey HSD test (P < 0.05). NaOCl significantly reduced the mechanical properties of dentin in all mechanical tests (P < 0.05) and no statistical difference was found among Ca(OCl)2, GSE and control group (P > 0.05). It can be concluded that Ca(OCl)2 and GSE may be alternative irrigant solutions, since they do not negatively affect the dentin mechanical properties.