A novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain, the Omicron variant (Pango lineage B.1.1.529), was identified in South Africa in late September 2021. This variant has ...multiple spike protein deletions and mutations, with 15 amino acid substitutions detected in the receptor-binding domain (RBD). These RBD substitutions are hypothesized to increase infectivity and reduce antibody affinity, which is supported by recent data showing that the Omicron variant spreads faster than the Delta variant (Pango lineage B.1.617.2). Thus, this increase in infectivity should lead to Omicron being the dominant variant and developing screening tests that discriminate between Omicron and Delta variants is urgently needed. In this study, we successfully developed a novel screening assay using high-resolution melting analysis, in which two genotypes at G446/L452 and S477/T478 RBD were determined (G446S/L452 and S477N/T478K for Omicron; G446/L452R and S477/T478K for Delta). Using synthetic DNA fragments, we confirmed both melting point and melting peak shape of the RBD Omicron variant was distinguishable from those of wild-type and the Delta variant. Although this study was conducted without clinical samples, these results suggest that our high-resolution melting (HRM)-based genotyping method can readily identify the Omicron and Delta variants. This simple method should contribute to the rapid identification of SARS-CoV-2 variants and thus prevent potential widespread infection and inflow of the Omicron variant.
Adjunctive use of laser devices as high reactive-level laser/light therapy (HLLT) or photobiomodulation therapy (PBMT) for periodontal therapy is known to be more effective on suppressing pain than ...conventional therapy, however, there are no systematic reviews addressed its effectiveness. This systematic review and meta-analysis aim to investigate the following clinical question (CQ): does adjunctive use of lasers with conventional therapy suppress the pain associated with periodontal treatment? A systematic and extensive literature search was performed to summarize the currently available knowledge to answer the CQ using the PubMed, Cochrane Library, and Web of Science databases for randomized controlled trials (RCTs) conducted before June 2020. Bias risk was assessed using the Cochrane tool for the risk of bias evaluation. A meta-analysis was performed on quantitative evaluation of pain control based on patient-reported outcomes. After an independent screening of 165 initial records, ten RCTs were included. Six of them focused on surgical procedures and the others on non-surgical periodontal pocket therapy. The protocols of HLLT, PBMT, and combination with HLLT and PBMT were employed in five, four and one RCTs, respectively. Following the assessment of bias risk, it is revealed that all RCTs had methodological weaknesses regarding the blinding of key personnel, although other bias risk factors were not evident. Meta-analysis showed that HLLT using erbium lasers significantly reduced the patient-reported pain immediately after treatment (two RCTs, p 0.0001), while PBMT using diode lasers significantly reduced pain 2-7 days after treatment (two RCTs, p 0.0001 to p = 0.03). The presented systematic review and meta-analysis suggest that the alternative use of HLLT using erbium lasers to conventional instrumentation can significantly suppress postoperative pain and that intraoperative or postoperative PBMT using diode lasers combined with periodontal surgery can significantly reduce postoperative pain. However, the evidence is still insufficient and more well-designed RCTs are required.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus causing coronavirus disease 2019 (COVID-19), has been expanding globally since late 2019. SARS-CoV-2, an RNA virus, ...has a genome sequence that can easily undergo mutation. Several mutated SARS-CoV-2 strains, including those with higher infectivity than others, have been reported. To reduce SARS-CoV-2 transmission, it is crucial to trace its infection sources. Here, we developed a simple, easy-to-use genotyping method to identify SARS-CoV-2 variants using a high-resolution melting (HRM) analysis.
We investigated five mutation sites, A23403G, G25563T, G26144T, T28144C, and G28882A, which are known strain determinants according to GISAID clades (L, S, V, G, GH, and GR).
We first employed synthetic DNA fragments containing the five characteristic sites for HRM analysis. All sequences clearly differentiated wild-type from mutant viruses. We then confirmed that RNA fragments were suitable for HRM analysis following reverse transcription. Human saliva did not negatively affect the HRM analysis, which supports the absence of a matrix effect.
Our results indicate that this HRM-based genotyping method can identify SARS-CoV-2 variants. This novel assay platform potentially paves the way for accurate and rapid identification of SARS-CoV-2 infection sources.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission has been reported worldwide and novel SARS-CoV-2 variants continue to emerge. A novel SARS-CoV-2 strain, the Delta variant ...(B.1.617.2), is spreading worldwide. The Delta variant has reportedly high infectivity and immune evasion potency. In June 2021, the World Health Organization categorized it as a variant of concern (VOC). Therefore, it is vital to develop tests that can exclusively identify the Delta variant. Here, we developed a rapid screening assay to detect characteristic mutations observed in the Delta variant using high-resolution melting (HRM) analysis. In this assay, we determined L452R and T478K, among which T478K is an identifier of the Delta variant since L452R is seen in other strains (Kappa and Epsilon variants). Additionally, nested PCR-based HRM analysis, which involved RT-PCR (1st PCR) and HRM analysis (2nd PCR), was developed to improve the specificity and sensitivity. Our method discriminated between the L452R mutant and wild-type L452. In addition, HRM analysis distinguished the T478K mutant from the wild-type T478. Seven clinical samples containing the Delta variant were successfully identified as L452R/T478K mutants. These results indicate that this HRM-based genotyping method can identify the Delta variant. This simple method should contribute to rapid identification of the Delta variant and the prevention of infection spread.
Periodontitis is an inflammatory disease characterized by the destruction of the periodontium. In the last decade, a new murine model of periodontitis has been widely used to simulate alveolar bone ...resorption and periodontal soft tissue destruction by ligation. Typically, 3-0 to 9-0 silks are selected for ligation around the molars in mice, and significant bone loss and inflammatory infiltration are observed within a week. The ligature-maintained period can vary according to specific aims. We reviewed the findings on the interaction of systemic diseases with periodontitis, periodontal tissue destruction, the immunological and bacteriological responses, and new treatments. In these studies, the activation of osteoclasts, upregulation of pro-inflammatory factors, and excessive immune response have been considered as major factors in periodontal disruption. Multiple genes identified in periodontal tissues partly reflect the complexity of the pathogenesis of periodontitis. The effects of novel treatment methods on periodontitis have also been evaluated in a ligature-induced periodontitis model in mice. This model cannot completely represent all aspects of periodontitis in humans but is considered an effective method for the exploration of its mechanisms. Through this review, we aimed to provide evidence and enlightenment for future studies planning to use this model.
Laser therapy has the potential to be an effective, minimally invasive procedure in periodontal therapy. The aim of the present review was to survey the relevant literature on the clinical ...application of lasers as a minimally invasive treatment for periodontitis and peri‐implant disease. Currently, there are a large number of published clinical studies and case reports that evaluate the adjunctive use of diode, carbon dioxide, neodymium‐doped yttrium aluminium garnet (Nd:YAG), erbium‐doped yttrium aluminium garnet (Er:YAG) and erbium, chromium‐doped: yttrium, scandium, gallium, garnet (Er,Cr:YSGG) lasers or antimicrobial photodynamic therapy for nonsurgical and minimally invasive surgical treatment of periodontal pockets. These procedures are expected not only to control inflammation but also to provide biostimulation effects with photonic energy. Recent meta‐analyses did not show statistically significant differences in pocket reduction and clinical attachment gain compared with mechanical debridement alone, although limited positive effects of adjunctive laser therapy were reported. At present, systematic literature approaches suggest that more evidence‐based studies need to be performed to support the integration of various laser therapies into the treatment of periodontal and peri‐implant diseases. The disparity between previous statistical analyses and individual successful clinical outcomes of laser applications might reveal the necessity of developing optimal laser‐treatment modalities of different wavelengths and better‐defined indications for each protocol.
Phthalic acid (PA) diesters are widely used in consumer products, as plasticizers, and are ubiquitous environmental pollutants. There is a growing concern about their adjuvant effect on allergic ...diseases. Although its precise mechanism remains unknown, possible involvement of transient receptor potential ankyrin 1 (TRPA1) has been suggested. Hence, in this study, the activation of human and mouse TRPA1s by a series of PA di- and monoesters was investigated using a heterologous expression system in vitro. Consequently, it was found that monoesters activated human TRPA1, where EC50 values were in the order of mono-hexyl > mono-heptyl > mono-n-octyl > mono-2-ethylhexyl > mono-isononyl and mono-isodecyl esters. Significant species differences in TRPA1 activation by PA monoesters were also discovered; PA monoesters activated human TRPA1 but not mouse TRPA1 in a concentration-dependent manner up to 50 µM. These findings suggest that PA esters may exert TRPA1-dependent adverse effects on humans, which have never been demonstrated in experimental animals.
Periodontal disease is a chronic inflammatory disease caused by periodontal bacteria. Recently, periodontal phototherapy, treatment using various types of lasers, has attracted attention. ...Photobiomodulation, the biological effect of low-power laser irradiation, has been widely studied. Although many types of lasers are applied in periodontal phototherapy, molecular biological effects of laser irradiation on cells in periodontal tissues are unclear. Here, we have summarized the molecular biological effects of diode, Nd:YAG, Er:YAG, Er,Cr:YSGG, and CO
lasers irradiation on cells in periodontal tissues. Photobiomodulation by laser irradiation enhanced cell proliferation and calcification in osteoblasts with altering gene expression. Positive effects were observed in fibroblasts on the proliferation, migration, and secretion of chemokines/cytokines. Laser irradiation suppressed gene expression related to inflammation in osteoblasts, fibroblasts, human periodontal ligament cells (hPDLCs), and endothelial cells. Furthermore, recent studies have revealed that laser irradiation affects cell differentiation in hPDLCs and stem cells. Additionally, some studies have also investigated the effects of laser irradiation on endothelial cells, cementoblasts, epithelial cells, osteoclasts, and osteocytes. The appropriate irradiation power was different for each laser apparatus and targeted cells. Thus, through this review, we tried to shed light on basic research that would ultimately lead to clinical application of periodontal phototherapy in the future.
Objectives: The primary aim was to address the following focused question: What is the clinical effect of laser application compared with mechanical debridement in non‐surgical periodontal therapy in ...patients with chronic periodontitis? A secondary aim was to survey the relevant literature in relation to safety of laser applications.
Material and Methods: Electronic databases of the PubMed and the Cochrane Library were searched and completed by manual searches up to December 2007.
Results: Following screening, 12 publications (11 studies) were eligible for the review. A meta‐analysis could not be performed due to the heterogeneity of the studies. The results from a narrative synthesis indicate that Er:YAG laser monotherapy resulted in similar clinical outcomes, both in the short and the long term (up to 24 months), compared with mechanical debridement. There is insufficient evidence to support the clinical application of either CO2, Nd:YAG, Nd:YAP, or different diode laser wavelengths.
Conclusions: The Er:YAG laser seems to possess characteristics most suitable for the non‐surgical treatment of chronic periodontitis. Research conducted so far has indicated that its safety and effects might be expected to be within the range reported for conventional mechanical debridement. However, the evidence from the evaluated studies is weak.
PDF
