Associated factors with the occurrence of in-hospital cardiac arrest in patients admitted to internal medicine wards for non-cardiovascular causes. / Factores asociados a la ocurrencia de paro cardiaco intrahospitalario en pacientes ingresados en salas de medicina interna por causas no cardiovasculares.

BACKGROUND AND OBJECTIVE: In-hospital cardiac arrest (IHCA) has a low survival rate, so it is essential to recognize the cases with the highest probability of developing it. The aim of this study is to identify factors associated with the occurrence of IHCA. MATERIAL AND METHODS: A single-center case-control study was conducted including 65 patients admitted to internal medicine wards for non-cardiovascular causes who experienced IHCA, matched with 210 admitted controls who did not present with IHCA. RESULTS: The main reason for admission was pneumonia. The most prevalent comorbidity was arterial hypertension. Four characteristics were strongly and independently associated with IHCA presentation, these are electrical left ventricular hypertrophy (LVH) (OR: 13.8; 95% IC: 4.7-40.7), atrial fibrillation (OR: 9.4: 95% CI: 4.3-20.6), the use of drugs with known risk of torsades de pointes (OR: 2.7; 95% CI: 1.3-5.5) and the combination of the categories known risk plus conditional risk (OR: 17.1; 95% CI: 6.7-50.1). The first two detected in the electrocardiogram taken at the time of admission. CONCLUSION: In admitted patients for non-cardiovascular causes, the use of drugs with a known risk of torsades de pointes, as well as the detection of electrical LVH and atrial fibrillation in the initial electrocardiogram, is independently associated with a higher probability of suffering a IHCA.

The effect of root canal preparation tapers on planktonic bacteria and biofilm reduction in the apical third: A correlative microtomography and microbiological laboratory study.

AIM: To evaluate the influence of different preparation tapers on the reduction in planktonic bacteria and biofilms of Enterococcus faecalis and Candida albicans in the apical third (4 mm) of the mesial roots of mandibular molars, correlating decontamination with canal shape. METHODOLOGY: After microtomography analysis for morphological standardization of the canals, 48 mandibular molar roots, each containing two canals (96 canals), were contaminated with E. faecalis and C. albicans and divided into four groups (n = 11) for canal instrumentation using ProDesign Logic 2 files with different tapers G (.03): # 25.03; G (.04): # 25.04; G (.05): # 25.05; and G (.06): # 25.06 and irrigation with 2.5% sodium hypochlorite. Four roots were examined under a scanning electron microscope (SEM) to qualitatively assess biofilm formation. Eight roots were used as the negative control group (samples were not contaminated). Bacteriological samples were taken exclusively from the apical third of the roots before and after chemical-mechanical preparation and bacterial counts were determined (CFU/mL). The final micro-CT scan was used to quantify the volume variation and unprepared canal area in the apical third. Statistical analysis was performed using the Kruskal-Wallis, Student-Newman-Keuls and Wilcoxon tests for analysis of microbiological data. anova and the Tukey or Games-Howell test were used for analysis of micro-CT data and Spearman's test for correlations (α = 5%). RESULTS: All groups showed a significant reduction in bacteria (p < .05), with no statistically significant difference between groups. There was no significant difference in per cent volume increase between groups. The unprepared area (Δ%) was affected by the file used (p = .026) and was significantly lower for G (.06) compared to G (.03). There was no statistically significant correlation among bacterial reduction, volume and unprepared area (p > .05). CONCLUSION: The different preparation tapers influenced root canal shaping in the apical third but did not improve decontamination in this region.

Diverse array of neutralizing antibodies elicited upon Spike Ferritin Nanoparticle vaccination in rhesus macaques.

The repeat emergence of SARS-CoV-2 variants of concern (VoC) with decreased susceptibility to vaccine-elicited antibodies highlights the need to develop next-generation vaccine candidates that confer broad protection. Here we describe the antibody response induced by the SARS-CoV-2 Spike Ferritin Nanoparticle (SpFN) vaccine candidate adjuvanted with the Army Liposomal Formulation including QS21 (ALFQ) in non-human primates. By isolating and characterizing several monoclonal antibodies directed against the Spike Receptor Binding Domain (RBD), N-Terminal Domain (NTD), or the S2 Domain, we define the molecular recognition of vaccine-elicited cross-reactive monoclonal antibodies (mAbs) elicited by SpFN. We identify six neutralizing antibodies with broad sarbecovirus cross-reactivity that recapitulate serum polyclonal antibody responses. In particular, RBD mAb WRAIR-5001 binds to the conserved cryptic region with high affinity to sarbecovirus clades 1 and 2, including Omicron variants, while mAb WRAIR-5021 offers complete protection from B.1.617.2 (Delta) in a murine challenge study. Our data further highlight the ability of SpFN vaccination to stimulate cross-reactive B cells targeting conserved regions of the Spike with activity against SARS CoV-1 and SARS-CoV-2 variants.

Antibody targeting of conserved sites of vulnerability on the SARS-CoV-2 spike receptor-binding domain.

Given the continuous emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VoCs), immunotherapeutics that target conserved epitopes on the spike (S) glycoprotein have therapeutic advantages. Here, we report the crystal structure of the SARS-CoV-2 S receptor-binding domain (RBD) at 1.95 Å and describe flexibility and distinct conformations of the angiotensin-converting enzyme 2 (ACE2)-binding site. We identify a set of SARS-CoV-2-reactive monoclonal antibodies (mAbs) with broad RBD cross-reactivity including SARS-CoV-2 Omicron subvariants, SARS-CoV-1, and other sarbecoviruses and determine the crystal structures of mAb-RBD complexes with Ab246 and CR3022 mAbs targeting the class IV site, WRAIR-2134, which binds the recently designated class V epitope, and WRAIR-2123, the class I ACE2-binding site. The broad reactivity of class IV and V mAbs to conserved regions of SARS-CoV-2 VoCs and other sarbecovirus provides a framework for long-term immunotherapeutic development strategies.

Reducing physical restraints in pediatrics: A quality improvement mixed-methods analysis of implementing a clinical debriefing process after behavioural health emergencies in a Children's Hospital.

INTRODUCTION: An increasing number of pediatric patients with mental and behavioral health (MBH) conditions present to Emergency Department (ED) and inpatient settings with behavioral events that require physical restraint (PR). PR usage is associated with adverse outcomes. Clinical debriefing (CD) programs have been associated with improved performance but have not been studied in this population. After implementing an MBH-CD program in our Children's Hospital, we aimed to decrease the baseline (7/2018-3/2021) rate of a second PR episode (2PR) by 50 % in the ED and inpatient settings over two years. METHODS: A multidisciplinary team implemented an MBH-CD process in April 2021 for hospital teams to use immediately after behavioral events. We included patients ≤18 years old, with an ED or inpatient discharge MBH diagnosis, between July 2018 and June 2023. Pre- and post-implementation secondary outcomes included the ED median duration of PR and the ED PR time per 1000 h of ED care. ED and inpatient mean length of stay (LOS) and mean monthly visits (MMV) in pre- and post-implementation were also compared. Qualitative analysis identified major themes. RESULTS: Post-implementation, the ED significantly decreased 2PR rate by 67 %; in inpatients, no significant change was demonstrated. Median duration of ED PR decreased from 112 to 71 min (p = 0.006) and ED PR time significantly decreased by 82 % (14.8 to 2.7 h per 1000 h). In the post-implementation period, mean LOS (ED and inpatient) and MMV (ED only) were significantly higher. Fifty-one percent of 494 behavioral alerts were debriefed. Median debriefing duration was 6 min (IQR 4,10). Common themes included cooperation and coordination (23 %) and clinical standards (14 %). DISCUSSION: Clinical debriefing implementation was associated with significant improvement in ED patient outcomes. Inpatient outcomes were unchanged, but debriefings in both settings should enable frontline teams to continuously identify opportunities to improve future outcomes.

In vitro cytotoxicity of resin cement and its influence on the expression of antioxidant genes.

AIM: This study evaluated cytotoxicity and antioxidant gene expression of resin cements on human gingival fibroblasts (hGF). MATERIALS AND METHOD: RelyX Ultimate™(RXU), Variolink™II(VLII), and RelyXU200™(RXU200) resin cements were incubated with culture medium for 24 h to obtain eluates. Then, the eluates were applied over hGF to assess cell viability at 24 h, 48 h, and 72 h and antioxidant gene expression at 24 h. hGF cultures non-exposed to the eluates were used as Control. Data were submitted to ANOVA and Bonferroni tests (α≤0.05). RESULTS: RXU and RXU200 reduced the number of viable cells in 24 h. Longer exposure to cement extracts caused cell death. Gene expression showed peroxiredoxin 1 (PRDX1) induction by all resin cement types, and superoxide dismutase 1 (SOD1) induction by RXU200 and VLII. Moreover, RXU200 induced not only PRDX1 and SOD1, but also glutathione peroxidase 1 (GPX1), catalase (CAT), and glutathione synthetase (GSS). CONCLUSIONS: All resin cements showed toxicity, and induced antioxidant genes in hGF. Antioxidant gene induction is at least partly associated with cytotoxicity of tested cements to oxidative stress experience.

OBJETIVO: O objetivo deste estudo foi avaliar a toxicidade dos cimentos resinosos Rely X Ultimate 2, Rely X U200 e Variolink II, bem como sua influência na expressão de genes antioxidantes em fibroblastos gengivais humanos. Materiais e Método: Corpos de prova de cada cimento foram colocados em meio de cultura por 24 h e os extratos correspondentes foram aplicados aos fibroblastos. A viabilidade celular foi avaliada após 24, 48 e 72 h de exposição pelo ensaio de exclusão do azul de tripano e MTT. A expressão gênica foi avaliada por PCR quantitativo após 24 h de exposição aos extratos. Estes parâmetros foram comparados aos das células não expostas aos cimentos. Os dados foram submetidos ao teste ANOVA, seguido pelo pós-teste de Bonferroni (a≤0.05). RESULTADOS: Os resultados demonstraram que todos os cimentos promoveram redução do número de células viáveis e da atividade mitocondrial nos períodos de 48 e de 72 h (p< 0,01), sendo que o Variolink II apresentou o menor efeito e os cimentos Rely X Ultimate e Rely X U200 promoveram similarmente os maiores efeitos. A análise de expressão gênica evidenciou influência significativa em todos os cimentos avaliados sobre os níveis de transcritos de PRDX1, SOD1, GPX1 e GSS (p> 0,05), com um aumento considerável no Rely X U200. Conclusão: A indução de genes antioxidantes está, pelo menos em parte, associada à citotoxicidade dos cimentos testados para a experiência de estresse oxidativo.

Conditioned Media from Human Pulp Stem Cell Cultures Improve Bone Regeneration in Rat Calvarial Critical-Size Defects.

The aim of this study was to test whether lyophilized conditioned media from human dental pulp mesenchymal stem cell cultures promote the healing of critical-size defects created in the calvaria of rats. Prior to the surgical procedure, the medium in which dental pulp stem cells were cultured was frozen and lyophilized. After general anesthesia, an 8 mm diameter bone defect was created in the calvaria of twenty-four rats. The defects were filled with the following materials: xenograft alone (G1) or xenograft associated with lyophilized conditioned medium (G2). After 14 or 42 days, the animals were euthanized, and the specimens processed for histologic and immunohistochemical analysis. Bone formation at the center of the defect was observed only in the G2 at 42 days. At both timepoints, increased staining for VEGF, a marker for angiogenesis, was observed in G2. Consistent with this, at 14 days, G2 also had a higher number of blood vessels detected by immunostaining with an anti-CD34 antibody. In conclusion, conditioned media from human dental pulp mesenchymal stem cell cultures had a positive effect on the regenerative process in rat critical-size bone defects. Both the formation of bone and enhancement of vascularization were stimulated by the conditioned media.

Surface topography of resorbable porcine collagen membranes, and their effect on early osteogenesis: An in vitro study.

OBJECTIVE: Guided tissue regeneration (GTR) is based on the use of different membranes that function as sealants and barriers in specific clinical situations. Among the several tissue production methods and origins, resorbable porcine-derived membranes are the most commonly used. Because these membranes are so diverse, and have several different clinical applications, doubts linger as to their effect in stimulating osteogenesis. The objective of this study was to make an in vitro evaluation of the viability and differentiation of osteoblastic cells cultured on the surface of the following collagen membranes: Jason® (Botiss Biomaterials), Collprotect® (Botiss Biomaterials), and Bio-Gide® (Geistlich). MATERIAL AND METHODS: Fragments of the 3 resorbable collagen membranes (5 × 5 mm) were used, and pre-osteoblastic SAOS-2 cells (ATCC, USA) were plated on their porous surfaces. Evaluation of the membranes was performed at 3, 5 and 7 days, considering the following parameters: (1) topographic analysis of the different surfaces by scanning electron microscope; (2) cellular viability by MTT, (3) quantification of type I collagen and osteopontin by Elisa. The quantitative analyses were carried out using a significance level of 5%. RESULTS: Collprotect® and Jason® membranes presented a rough surface with an irregular aspect on both sides, while double-layered Bio-Gide® had one layer with a smooth surface and the other with a rough surface along each respective length. The viability assays revealed that the cells cultured the cells grown on Collprotect® showed higher viability than those grown in Bio-Gide® or Jason®, especially after 5 and 7 days. After 3 and 5 days, evaluation of type I collagen showed that the cells plated on the Jason® and Collprotect® surfaces had greater collagen secretion than those plated on BioGide®. After 7 days, an increase in osteopontin levels was observed when the cells were plated on all the experimental membranes, compared with the control group. CONCLUSION: All the tested membranes were suitable for use in GTR clinical procedures. Their indication in specific regenerative cases depends on the mechanical and biological properties of their originating tissues, thus enabling better results and assertive choices by dental professionals.

Sema4D is diminished in leukocyte platelet-rich fibrin and impairs pre-osteoblastic MC3T3-E1 cells' functionality.

OBJECTIVE: Semaphorin 4D (Sema4D) is a coupling factor expressed on osteoclasts that may hinder osteoblast differentiation. Since the leukocyte platelet-rich fibrin (L-PRF) membrane promotes growth factor concentration, this study aims to quantify the amount of Sema4D in L-PRF membranes, and analyze the impact of Sema4D on osteoblast cell function in vitro. DESIGN: Enzyme-linked immunosorbent assay (ELISA) was used to quantify the levels of Sema4D in both L-PRF and whole blood (serum). To analyze the impairment of Sema4D on osteoblasts, MC3T3-E1 cells were induced to osteogenic differentiation and exposed to Sema4D ranging from 10 to 500 ng/ml concentrations. The following parameters were assayed: 1) cell viability by MTT assay after 24, 48, and 72 h; 2) matrix mineralization by Alizarin Red staining after 14 days, 3) Runt-related transcription factor 2 (RUNX-2), osteocalcin (OCN), osteonectin (ONC), bone sialoprotein (BSP) and alkaline phosphatase (ALP) gene expression by qPCR. For all data, the significance level was set at 5%. RESULTS: The amount of Sema4D in the whole blood (serum) was higher than in L-PRF. Osteoblasts exposed to Sema4D at all tested concentrations exhibited a decrease in matrix mineralization formation as well in RUNX-2, OCN, ONC, BSP, and ALP gene expression (p < 0.05). CONCLUSION: The presence of Sema4D, a molecule known for suppressing osteoblast activity, diminishes within L-PRF, enhancing its ability to facilitate bone regeneration.

In vitro cytotoxicity of resin cement and its influence on the expression of antioxidant genes / Avaliação in vitro da toxicidade de cimentos resinosos e sua influência na expressão de genes antioxidantes em fibroblastos humanos

ABSTRACT Aim: This study evaluated cytotoxicity and antioxidant gene expression of resin cements on human gingival fibroblasts (hGF). Materials and Method: RelyX Ultimate™(RXU), Variolink™II(VLII), and RelyXU200™(RXU200) resin cements were incubated with culture medium for 24 h to obtain eluates. Then, the eluates were applied over hGF to assess cell viability at 24 h, 48 h, and 72 h and antioxidant gene expression at 24 h. hGF cultures non-exposed to the eluates were used as Control. Data were submitted to ANOVA and Bonferroni tests (α≤0.05). Results: RXU and RXU200 reduced the number of viable cells in 24 h. Longer exposure to cement extracts caused cell death. Gene expression showed peroxiredoxin 1 (PRDX1) induction by all resin cement types, and superoxide dismutase 1 (SOD1) induction by RXU200 and VLII. Moreover, RXU200 induced not only PRDX1 and SOD1, but also glutathione peroxidase 1 (GPX1), catalase (CAT), and glutathione synthetase (GSS). Conclusions: All resin cements showed toxicity, and induced antioxidant genes in hGF. Antioxidant gene induction is at least partly associated with cytotoxicity of tested cements to oxidative stress experience.

RESUMO Objetivo: O objetivo deste estudo foi avaliar a toxicidade dos cimentos resinosos Rely X Ultimate 2, Rely X U200 e Variolink II, bem como sua influência na expressão de genes antioxidantes em fibroblastos gengivais humanos. Materiais e Método: Corpos de prova de cada cimento foram colocados em meio de cultura por 24 h e os extratos correspondentes foram aplicados aos fibroblastos. A viabilidade celular foi avaliada após 24, 48 e 72 h de exposição pelo ensaio de exclusão do azul de tripano e MTT. A expressão gênica foi avaliada por PCR quantitativo após 24 h de exposição aos extratos. Estes parâmetros foram comparados aos das células não expostas aos cimentos. Os dados foram submetidos ao teste ANOVA, seguido pelo pós-teste de Bonferroni (a≤0.05). Resultados: Os resultados demonstraram que todos os cimentos promoveram redução do número de células viáveis e da atividade mitocondrial nos períodos de 48 e de 72 h (p < 0,01), sendo que o Variolink II apresentou o menor efeito e os cimentos Rely X Ultimate e Rely X U200 promoveram similarmente os maiores efeitos. A análise de expressão gênica evidenciou influência significativa em todos os cimentos avaliados sobre os níveis de transcritos de PRDX1, SOD1, GPX1 e GSS (p> 0,05), com um aumento considerável no Rely X U200. Conclusão: A indução de genes antioxidantes está, pelo menos em parte, associada à citotoxicidade dos cimentos testados para a experiência de estresse oxidativo.

Targeting the Spike Receptor Binding Domain Class V Cryptic Epitope by an Antibody with Pan-Sarbecovirus Activity.

Novel therapeutic monoclonal antibodies (MAbs) must accommodate comprehensive breadth of activity against diverse sarbecoviruses and high neutralization potency to overcome emerging variants. Here, we report the crystal structure of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor binding domain (RBD) in complex with MAb WRAIR-2063, a moderate-potency neutralizing antibody with exceptional sarbecovirus breadth, that targets the highly conserved cryptic class V epitope. This epitope overlaps substantially with the spike protein N-terminal domain (NTD) -interacting region and is exposed only when the spike is in the open conformation, with one or more RBDs accessible. WRAIR-2063 binds the RBD of SARS-CoV-2 WA-1, all variants of concern (VoCs), and clade 1 to 4 sarbecoviruses with high affinity, demonstrating the conservation of this epitope and potential resiliency against variation. We compare structural features of additional class V antibodies with their reported neutralization capacity to further explore the utility of the class V epitope as a pan-sarbecovirus vaccine and therapeutic target. IMPORTANCE Characterization of MAbs against SARS-CoV-2, elicited through vaccination or natural infection, has provided vital immunotherapeutic options for curbing the COVID-19 pandemic and has supplied critical insights into SARS-CoV-2 escape, transmissibility, and mechanisms of viral inactivation. Neutralizing MAbs that target the RBD but do not block ACE2 binding are of particular interest because the epitopes are well conserved within sarbecoviruses and MAbs targeting this area demonstrate cross-reactivity. The class V RBD-targeted MAbs localize to an invariant site of vulnerability, provide a range of neutralization potency, and exhibit considerable breadth against divergent sarbecoviruses, with implications for vaccine and therapeutic development.

Antibacterial nanocomposite of chitosan/silver nanocrystals/graphene oxide (ChAgG) development for its potential use in bioactive wound dressings.

An adequate wound dressing reduces time of healing, provides cost-effective care, thereby improving patients' quality life. An antimicrobial bioactivity is always desired, for that reason, the objective of this work is to design an antimicrobial nanocomposite of chitosan/silver nanocrystals/graphene oxide (ChAgG). ChAgG nanostructured composite material is composed of chitosan from corn (Ch), and silver nanocrystals from garlic (Allium sativum). The nanocomposite obtained is the result of a series of experiments combining the graphene oxide (GrOx) with two members of the Amaryllidaceae family; garlic and onion (Allium cebae), which contain different sulfur materials. The characterization arrays confirmed the successful production of silver crystal, graphene oxidation and the blending of both components. The role of the chitosan as a binder between graphene and silver nanocrystals is proved. Moreover, the study discusses garlic as an optimal source that permits the synthesis of silver nanocrystals (AgNCs) (⁓ 2 to 10 nm) with better thermal and crystallinity properties. It was also confirmed the successful production of the ChAgG nanocomposite. Escherichia coli and Staphylococcus aureus were used to demonstrate the antibacterial bioactivity and L-929 fibroblast cells were utilized to visualize their biocompatibility. The proposed ChAgG nanomaterial will be useful for functionalizing specific fiber network that represents current challenging research in the fabrication of bioactive wound dressings.

Microbiological analysis of bacterial sealing of internal conical implants with different taper angles.

The present study evaluated the effect of the taper angle of different internal conical connection implants and cyclic loading on the implant-abutment bacterial seal. A total of 96 implant-abutment sets were divided into eight groups. Four groups of different taper degrees with cyclic mechanical loading of 500,000 cycles per sample, with a 120-N load at 2 Hz before analysis [16DC (16-degree, cycled), 11.5DC (11.5-degree, cycled), 3DC (3- degree, cycled) and 4DC (4- degree, cycled)] were compared to four control groups without cyclic loading [16D (16-degree), 11.5D (11.5-degree), 3D (3-degree), and 4D (4-degree)]. Microbiological analysis was performed by immersing all samples in a suspension containing Escherichia coli and incubating them at 37°C. After 14 days, the presence of bacterial seals was evaluated. Fisher-Freeman-Halton exact tests and binomial tests were performed (5% significance level). The groups showed significant differences in bacterial seal, and mechanical load cycling improved the bacterial seal in the 3DC group. In all other groups, no significant differences in bacterial seal were found between cycled and uncycled samples. To conclude, the internal conical connection with a 3-degree taper angle showed better results than the other connection with different angles when subjected to load cycling. However, none of the angles tested were fully effective in sealing the implant-abutment interface.

Hyperspectral camera as a compact payload architecture for remote sensing applications.

Monitoring and observation over the surface of the Earth have been a matter of global interest. In this path, recent efforts aim to develop a spatial mission to perform remote sensing applications. Mainly, CubeSat nanosatellites have emerged as a standard for developing low-weight and small-sized instruments. In terms of payloads, state-of-the-art optical systems for CubeSats are expensive and designed to work in general use cases. To overcome these limitations, this paper presents a 1.4 U compact optical system to acquire spectral images from a CubeSat standard satellite at the height of 550 km. To validate the proposed architecture, optical simulations using ray tracing simulation software are presented. Because the performance of computer vision tasks is highly related to data quality, we compared the optical system in terms of the classification performance on a real remote sensing application. The performances of the optical characterization and land cover classification show that the proposed optical system achieves a compact instrument, operating at a spectral range from 450 nm to 900 nm discretized on 35 spectral bands. The optical system has an overall f-number of 3.41 with a ground sampling distance of 52.8 m and a swath of 40 km. Additionally, the design parameters for each optical element are publicly available for validation, repeatability, and reproducibility of the results.

Pulp-Dentin Complex Regeneration with Cell Transplantation Technique Using Stem Cells Derived from Human Deciduous Teeth: Histological and Immunohistochemical Study in Immunosuppressed Rats.

The aim of this study was to histologically verify the performance of pulp-derived stem cells used in the pulp-dentin complex regeneration. Maxillary molars of 12 immunosuppressed rats were divided into two groups: the SC (stem cells) group, and the PBS (just standard phosphate-buffered saline) group. After pulpectomy and canal preparation, the teeth received the designated materials, and the cavities were sealed. After 12 weeks, the animals were euthanized, and the specimens underwent histological processing and qualitative evaluation of intracanal connective tissue, odontoblast-like cells, intracanal mineralized tissue, and periapical inflammatory infiltrate. Immunohistochemical evaluation was performed to detect dentin matrix protein 1 (DMP1). In the PBS group, an amorphous substance and remnants of mineralized tissue were observed throughout the canal, and abundant inflammatory cells were observed in the periapical region. In the SC group, an amorphous substance and remnants of mineralized tissue were observed throughout the canal; odontoblasts-like cells immunopositive for DMP1 and mineral plug were observed in the apical region of the canal; and a mild inflammatory infiltrate, intense vascularization, and neoformation of organized connective tissue were observed in the periapical region. In conclusion, the transplantation of human pulp stem cells promoted partial pulp tissue neoformation in adult rat molars.

Short implants: Influence of different diameters, torques, and transmucosal heights of straight prosthetic abutments on screw preload loss after cycling.

This study evaluated the influence of different implant diameters, insertion torques, and transmucosal heights on the loosening of abutments installed on short implants, after mechanical cycling. The Morse taper connection implants (n = 96) tested were 5 mm high, divided according to the platform diameter: 4 or 6 mm. A universal abutment was coupled to each implant (with different transmucosal heights: 1 or 5 mm). The sets were subdivided into 20- and 32-Ncm torque. After the cycle fatigue test, the detorque values were measured with a digital torque indicator. After mechanical cycling, the mean detorque values obtained for the abutment with 20-Ncm insertion torque were lower than for implants with 32-Ncm insertion torque, regardless of the platform diameter or transmucosal height. In the 20-Ncm torque group, there was no statistically significant difference in the detorque values between platform diameters or transmucosal heights. Otherwise, for 32-Ncm sets, a smaller platform diameter (4 mm), and a longer transmucosal height (5 mm) showed the lowest detorque values. In conclusion, implants placed with 32-Ncm insertion torque and abutments with 1 mm transmucosal height and a 6 mm implant diameter demonstrated the highest detorque values.

Can Collagen Membrane on Bone Graft Interfere with Light Transmission and Influence Tissue Neoformation During Photobiomodulation? A Preliminary Study.

Objective: This study qualitatively and quantitatively evaluated the transmission of light through a collagen membrane and the consequent local bone formation in a critical bone defect in vitro and in an animal model. Background: Currently, bone substitutes and collagen membranes are used to promote new bone formation; however, when associated with photobiomodulation, biomaterials can act as a barrier, hindering the passage of light radiation to the area to be treated. Methods: Light transmittance was evaluated in vitro with a power meter and a 100 mW, 808 nm laser source with and without membrane. Twenty-four male rats received a critical surgical defect of 5 mm in diameter in the calvarial bone, subsequently a biomaterial (Bio-Oss; Geistlich®, Switzerland) was applied, and the animals were divided into the following three groups: G1-collagen membrane and no irradiation; G2-collagen membrane and photobiomodulation (irradiation with 4 J of 808 nm); and G3-photobiomodulation (4 J) followed by a collagen membrane. Histomophometric analyses were performed at 7 and 14 days after euthanasia. Results: The membrane reduced the light transmittance (808 nm) by an average of 78%. Histomophometric analyses showed significant differences in new blood vessels on day 7 and bone neoformation on day 14. Irradiation without membrane interposition resulted in a 15% more neoformed bone compared with the control (G1), and 6.5% more bone compared with irradiation over the membrane (G2). Conclusions: The collagen membrane interferes with light penetration during photobiomodulation, decreases light dosimetry on the wound area, and interferes with bone neoformation.

Ad26.COV2.S and SARS-CoV-2 spike protein ferritin nanoparticle vaccine protect against SARS-CoV-2 Omicron BA.5 challenge in macaques.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines demonstrate reduced protection against acquisition of BA.5 subvariant but are still effective against severe disease. However, immune correlates of protection against BA.5 remain unknown. We report the immunogenicity and protective efficacy of vaccine regimens consisting of the vector-based Ad26.COV2.S vaccine and the adjuvanted spike ferritin nanoparticle (SpFN) vaccine against a high-dose, mismatched Omicron BA.5 challenge in macaques. The SpFNx3 and Ad26 + SpFNx2 regimens elicit higher antibody responses than Ad26x3, whereas the Ad26 + SpFNx2 and Ad26x3 regimens induce higher CD8 T cell responses than SpFNx3. The Ad26 + SpFNx2 regimen elicits the highest CD4 T cell responses. All three regimens suppress peak and day 4 viral loads in the respiratory tract, which correlate with both humoral and cellular immune responses. This study demonstrates that both homologous and heterologous regimens involving Ad26.COV2.S and SpFN vaccines provide robust protection against a mismatched BA.5 challenge in macaques.