Adjunctive therapies for in vitro carious lesions: Antimicrobial activity,activation of dentin metalloproteinases and effects on dental pulp cells

BackgroundAdjunctive therapies used before dental restorative procedures may encourage carious tissue removal. Beyond promising antimicrobial properties, treatments could positively modulate the dentin-pulp complex while not interfering with restoration survival. Herein, we evaluated a set of substances and their effects on carious lesions and the underlying dentin or pulp cells.MethodsArtificial caries lesions were developed in bovine teeth cavities immersed in Streptococcus mutans and Lactobacillus casei co-cultures. The cavities were treated according to the following groups: Phosphate Buffer Saline (PBS), Chlorhexidine (CHX), Papac&#225;rie® (Papain gel), Ozone (O₃), and antimicrobial Photodynamic Therapy (aPDT). After treatments, samples were cultivated to count isolated microbial colonies. The zymography assay evaluated the activity of dentin metalloproteinases (MMP-2 and MMP-9). Cell viability was indirectly assessed on human dental pulp cells after 24, 72, or 120 h, whereas the odontodifferentiation potential was evaluated after ten days of cell culture.ResultsCHX and aPDT led to around 1 log bacterial load reduction. PBS, CHX, and aPDT showed the eventual expression of MMP-2 and MMP-9. Cell viability was reduced (< 30%) after 120 h for all groups compared to the control. CHX, O3, and aPDT induced greater odontodifferentiation (≈ 20% higher) than PBS and papain gel.ConclusionAdjunctive therapies presented little or no biological significance in reducing bacterial load in artificial carious lesions. Although the activation of endogenous metalloproteinases may represent a possible concern for adhesive restorations, some of these treatments may have a positive role in dental pulp tissue repair.     

How can biophotonics help dentistry to avoid or minimize cross infection by SARS-CoV-2?

Biophotonics is defined as the combination of biology and photonics (the physical science of the light). It is a general term for all techniques that deal with the interaction between biological tissues/cells and photons (light). Biophotonics offers a great variety of techniques that can facilitate the early detection of diseases and promote innovative theragnostic approaches. As the COVID-19 infection can be transmitted due to the face-to-face communication, droplets and aerosol inhalation and the exposure to saliva, blood, and other body fluids, as well as the handling of sharp instruments, dental practices are at increased risk of infection. In this paper, a literature review was performed to explore the application of Biophotonics approaches in Dentistry focusing on the COVID-19 pandemic and how they can contribute to avoid or minimize the risks of infection in a dental setting. For this, search-related papers were retrieved from PubMED, Scielo, Google Schoolar, and American Dental Association and Centers for Disease Control and Prevention databases. The body of evidence currently available showed that Biophotonics approaches can reduce microorganism load, decontaminate surfaces, air, tissues, and minimize the generation of aerosol and virus spreading by minimally invasive, time-saving, and alternative techniques in general. However, each clinical situation must be individually evaluated regarding the benefits and drawbacks of these approaches, but always pursuing less-invasive and less aerosol-generating procedures, especially during the COVID-19 pandemic.     

肌萎缩侧索硬化伴认知功能障碍的研究进展

认知功能障碍在肌萎缩侧索硬化（ALS）患者中是普遍存在的，ALS伴认知功能障碍常提示预后不良。近年来对ALS患者认知功能障碍的研究取得了一定的进展，本文对ALS伴认知功能障碍的临床特点、生物标志物、遗传学特征和最新治疗进展进行综述，以期为ALS伴认知功能障碍的临床诊疗提供新思路。     

The Predictors of Painful Diabetic Neuropathy and Its Effect on Quality of Life

BackgroundKnowing the prevalence and predictors of neuropathic pain and its impacts on the quality of life (QoL) using measurement tools is important for good diabetes management. In Turkish society, neuropathic pain, its predictors and its impact on the quality of life of diabetics are not considered enough.ObjectivesThis study examined the prevalence and predictors of neuropathic pain and its impacts on the quality of life in diabetics in Rize Province, Turkey.DesignThis study was designed as a cross-sectional, correlational study.SettingData collected through face-to-face interviews. The sample size was determined using the formula [n= N t²pq / d² (N-1) + t²pq].ParticipantThe sample of the study consisted of 122 people with diabetes who visited the diabetes outpatient clinic of the hospital.MethodsA Personal Information Form, Douleur Neuropathique en 4 questions (DN4), and Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) were used to collect data. Pain intensity was measured using Visual Analogue Scale (VAS)ResultsThe prevalence of the diagnosed painful diabetic polyneuropathy (PDPN) was found to be 22.9%. On the other hand, the prevalence of the undiagnosed PDPN was found to be 44.3% according to DN4 and 27.9% according to LANSS. The VAS pain score was determined as 1.99±1.20 (range: 1-5). In the people with PDPN, nephropathy was seen 4.514 times more frequently according to DN4 and 7.217 times more frequently according to LANSS. Painful diabetic peripheral neuropathy had negative effects on all dimensions of QoL except for social function and mental health (p <0.05).ConclusionsIt is important for nurses to determine the prevalence and predictive factors of PDPN in their region and to evaluate the effect of pain on the quality of life of diabetics. Nurses should attempt to increase the quality of life of people with diabetes by reducing the predictors affecting pain.     

Single-dose replicating poxvirus vector-based RBD vaccine drives robust humoral and T cell immune response against SARS-CoV-2 infection

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Integrative Expression,Survival Analysis and Cellular miR-2909 Molecular Interplay in MRN Complex Check Point Sensor Genes (MRN-CSG) Involved in Breast Cancer

BackgroundBreast cancer, an emerging global challenge, is evidenced by recent studies of miRNAs involvement in DNA repair gene variants (MRE11, RAD50, and NBN as checkpoint sensor genes (CSG) – MRN-CSG). The identification of various mutations in MRN-CSG and their interactions with miRNAs is still not understood. The emerging studies of miR-2909 involvement in other cancers led us to explore its role as molecular mechanistic marker in breast cancer.Materials and MethodsThe genomic and proteomic data of MRN-CSG of breast cancer patients (8426 samples) was evaluated to identify the mutation types linked with the patient's survival rate. Additionally, molecular, 3D-structural and functional analysis was performed to identify miR-2909 as regulator of MRN-CSG.ResultsThe genomic and proteomic data analysis shows genetic alterations with majority of missense mutations [RAD50 (0.7%), MRE11 (1.5%), and NBN (11%)], though with highest MRE11 mRNA expression in invasive ductal breast carcinoma as compared to other breast cancer types. The Kaplan–Meier survival curves suggest higher survival rate for unaltered groups as compared to the altered group. Network analysis and disease association of miR-2909 and MRN-CSG shows strong interactions with other partners. The molecular hybridization between miR-2909-RAD50 and miR-2909-MRE11 complexes showed thermodynamically stable structures. Further, argonaute protein, involved in RNA silencing, docking studies with miR-MRE11-mRNA and miR-RAD50-mRNA hybridized complexes showed strong binding affinity.ConclusionThe results suggest that miR-2909 forms strong thermodynamically stable molecular hybridized complexes with MRE11 and RAD50 mRNAs which further strongly interacts with argonaute protein to show potential molecular mechanistic role in breast cancer.     

An Artificial Gut/Absorption Simulator: Simultaneous Evaluation of Desupersaturation and Absorption from Ketoconazole Supersaturated Solutions

For supersaturating formulations of BCS-II compounds, which by definition have high intestinal permeability, a closed USP apparatus does not provide the necessary absorptive conditions during dissolution. To address this, an artificial gut simulator (AGS) has been constructed consisting of a 2.5 mL donor compartment in which a hollow fiber-based absorption module is suspended. Drug from donor diffuses across the hollow fiber membrane to be absorbed by the continuously flowing intraluminal receiver fluid. The membrane surface area and intraluminal fluid flow rate are tuned to obtain the physiologically observed absorption rate constant for a weakly basic, poorly water-soluble model compound, ketoconazole (KTZ). Supersaturated solutions of KTZ were generated in the donor in pH 6.5 phosphate buffer by the pH-shift method in the absence (closed system, control) and presence (open system, biorelevant) of an optimally or suboptimally tuned absorption module. Drug concentrations in the donor and intraluminal fluids were determined by in-line UV spectroscopy. The presence of an absorptive sink reduced the supersaturated solution's crystallization propensity, more so in the case of the optimally tuned AGS. This study demonstrates the significance of simulating absorption of drug at a physiological rate during dissolution studies, especially to predict the performance of formulations of BCS-II drugs.