COVID-19: A Recommendation to Examine the Effect of Mouthrinses with β-Cyclodextrin Combined with Citrox in Preventing Infection and Progression

Recent developments in the field of radiotherapy for the management of lung cancer

Lung cancer has a poor prognosis, and further improvements in outcomes are needed. Radiotherapy plays an important role in the treatment of unresectable lung cancer, and there have been recent developments in the field of radiotherapy for the management of lung cancer. However, to date, there have been few reviews on the improvement in treatment outcomes associated with high precision radiotherapy for lung cancer. Thus, this review aimed to summarize the recent developments in radiotherapy techniques and indicate the future directions in the use of radiotherapy for lung cancer. Stereotactic body radiotherapy (SBRT) for unresectable stage I lung cancer has been reported to improve local control rates without severe adverse events, such as radiation pneumonitis. For locally advanced lung cancer, a combination of chemoradiotherapy and adjuvant immune checkpoint inhibitors dramatically improves treatment outcomes, and intensity-modulated radiotherapy (IMRT) enables safer radiation therapy with less frequent pneumonitis. Particle beam therapy, such as carbon-ion radiotherapy and proton beam therapy, has been administered as advanced medical care for patients with lung cancer. Since 2024, it has been covered under insurance for early stage lung cancer with tumors ≤ 5 cm in size in Japan. In addition to chemotherapy, local ablative radiotherapy improves treatment outcomes in patients with oligometastatic stage IV lung cancer. A particular problem with radiotherapy for lung cancer is that the target location changes with respiratory motion, and various physical methods have been used to control respiratory motion. Recently, coronavirus disease has had a major impact on lung cancer treatment, and cancer treatment during situations, such as the coronavirus pandemic, must be performed carefully. To improve treatment outcomes for lung cancer, it is necessary to fully utilize evolving radiotherapy modalities, and the role of radiotherapy in lung cancer treatment is expected to increase.

SARS-CoV-2 entry and fusion are independent of ACE2 localization to lipid rafts

Membrane fusion occurs at the early stages of SARS-CoV-2 replication, during entry of the virus, and later during the formation of multinucleated cells called syncytia. Fusion is mediated by the binding of the viral Spike protein to its receptor ACE2. Lipid rafts are dynamic nanodomains enriched in cholesterol and sphingolipids. Rafts can act as platforms for entry of different viruses by localizing virus receptors, and attachment factors to the same membrane domains. Here, we first demonstrate that cholesterol depletion by methyl-beta-cyclodextrin inhibits Spike-mediated fusion and entry. To further study the role of ACE2 lipid raft localization in SARS-CoV-2 fusion and entry, we designed a GPI-anchored ACE2 construct. Both ACE2 and ACE2-GPI proteins were similarly expressed at the plasma membrane. Through membrane flotation assays, we show that in different cell lines, ACE2-GPI localizes predominantly to raft domains of the plasma membrane while ACE2 is non-raft associated. We then compare the ability of ACE2 and ACE2-GPI to permit SARS-CoV-2 entry, replication, and syncytia formation of different viral variants. We find little difference in the two proteins. Our results demonstrate that SARS-CoV-2 entry and fusion are cholesterol-dependent and raft-independent processes.IMPORTANCERafts are often exploited by viruses and used as platforms to enhance their entry into the cell or spread from cell to cell. The membrane localization of ACE2 and the role of lipid rafts in SARS-CoV-2 entry and cell-to-cell spread are poorly understood. The function of lipid rafts in viral fusion is often studied through their disruption by cholesterol-depleting agents. However, this process may have off-target impacts on viral fusion independently of lipid-raft disruption. Therefore, we created an ACE2 construct that localizes to lipid rafts using a GPI anchor. Conversely, wild-type ACE2 was non-raft associated. We find that the localization of ACE2 to lipid rafts does not modify the fusion dynamics of SARS-CoV-2.

Antiseptics: An expeditious third force in the prevention and management of coronavirus diseases

Notably, severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS) and coronavirus disease 2019 (COVID-19) have all had significant negative impact on global health and economy. COVID-19 alone, has resulted to millions of deaths with new cases and mortality still being reported in its various waves. The development and use of vaccines have not stopped the transmission of SARS coronavirus 2 (SARS-CoV-2), the etiological agent of COVID-19, even among vaccinated individuals. The use of vaccines and curative drugs should be supplemented with adoption of simple hygiene preventive measures in the fight against the spread of the virus, especially for healthcare workers. Several virucidal topical antiseptics, such as povidone-iodine (PVP-I), citrox, cyclodextrins among others, have been demonstrated to be efficacious in the inactivation of SARS-CoV-2 and other coronaviruses in both in vitro and in vivo studies. The strategic application of these virucidal formulations could provide the additional impetus needed to effectively control the spread of the virus. We have here presented a simple dimension towards curtailing the dissemination of COVID-19, and other coronaviruses, through the application of effective oral, nasal and eye antiseptics among patients and medical personnel. We have further discussed the mechanism of action of some of these commonly available virucidal solutions while also highlighting some essential controversies in their use.

Transport Properties in Multicomponent Systems Containing Cyclodextrins and Nickel Ions

In this work, we propose a comprehensive experimental study of the diffusion of nickel ions in combination with different cyclodextrins as carrier molecules for enhanced solubility and facilitated transport. For this, ternary mutual diffusion coefficients measured by Taylor dispersion method are reported for aqueous solutions containing nickel salts and different cyclodextrins (that is, α-CD, β-CD, and γ-CD) at 298.15 K. A combination of Taylor dispersion and other methods, such as UV-vis spectroscopy, will be used to obtain complementary information on these systems. The determination of the physicochemical properties of these salts with CDs in aqueous solution provides information that allows us to understand solute-solvent interactions, and gives a significant contribution to understanding the mechanisms underlying diffusional transport in aqueous solutions, and, consequently, to mitigating the potential toxicity associated with these metal ions. For example, using mutual diffusion data, it is possible to estimate the number of moles of each ion transported per mole of the cyclodextrin driven by its own concentration gradient.

Use of over-the-counter mouthwashes as an additional measure in individual oral prophylaxis on adults with plaque-induced gingivitis: a double-blind, parallel, randomized controlled trial

BACKGROUND

Plaque-induced gingivitis is a chronic inflammatory condition characterized by complete reversibility of tissue damage once the periodontal biofilm has been disorganised. The aim of this study was to evaluate the efficacy of two commercially available mouthwashes (MWs) versus a chlorhexidine (CHX) 0.12% MW in reducing gingival bleeding (GB) in adults with plaque-induced gingivitis.

METHODS

The present study was a double-blind, parallel, randomized controlled trial involving 6492 gingival sites (i.e. 39 subjects × 28 teeth × 6 sites/tooth) aged 18-75 years. During a 2-week period, subjects were randomized to receive MWs: a control CHX 0.12% MW (group C, 1818 sites); a MW test containing CHX 0.09% + Citrox®/P complex (group CX, 2628 sites); a MW test based on natural compounds (group P, 2016 sites). GB was assessed at the inclusion visit (T0) and after 2 weeks of MW use (T1). Analyses of GB were compared between groups and then restricted to subjects with bleeding sites between 10 and 30% (moderate gingivitis) or ≥ 30% (severe gingivitis) at T0. Pairwise comparisons were made between groups and logistic regression was used to identify correlates of GB (T1).

RESULTS

For total bleeding site analysis, GB reduction between T0 and T1 ranged from 23% (C), 26% (CX) and 36% (P), respectively (all p < 0.05). Multiple comparison between groups showed that group C was significantly less effective (p < 0.05) than groups CX and P. Splitting the analysis, in patients with severe gingivitis (≥ 30% bleeding sites at T0), all MWs had a positive effect on GB with a reduction at T1 of 36% (C), 33% (CX) and 42% (P), respectively. While GB reduction between T0 and T1, was significant for all groups, the comparison among groups showed no significant difference between group C and CX, whereas the improvement was significant for group P. On the other hand, in adults with moderate gingivitis (< 30% bleeding sites at T0), only CX and P had a positive effect on GB reduction at T1(9% in CX and 2% in P, respectively), although the differences between the three groups were not significant.

CONCLUSION

The daily use of MWs with natural components (groups P and CX) for 2 weeks should be considered positively as an adjunct to individual oral prophylaxis to reduce GB compared to the control MW containing CHX 0.12% (group C) in healthy adults with plaque-induced gingivitis. For subjects with severe gingivitis, it is advisable to first use natural MW (P) and then MW based on CHX 0.09% with natural components (CX), compared to MW with CHX 0.12% (C). For adults with moderate gingivitis, P and CX can be advisable, even if no definitive recommendations can be drawn.

TRIAL REGISTRATION

ACTRN12622000215729, 07/02/2022.

Effectiveness of mouthwashes on reducing SARS-CoV-2 viral load in oral cavity: a systematic review and meta-analysis

BACKGROUND

The risk of SARS-COV-2 transmission is relatively high during dental procedures. A study was conducted to investigate the effects of mouthwashes on SARS-COV-2 viral load reduction in the oral cavity.

METHODS

A systematic search was performed in PubMed, EMBASE, Scopus, Web of Science, and Cochrane library for relevant studies up to 20 July, 2022. Randomized and non-randomized clinical trial and quasi-experimental studies evaluating patients with Covid-19 infection (patients) who used mouthwashes (intervention) compared to the same patients before using the mouthwash (comparison) for reducing the SARS-COV-2 load or increasing the cycle threshold (Ct) value (outcome) were searched according to PICO components. Three independent reviewers conducted literature screening and data extraction. The Modified Downs and Black checklist was used for quality assessment. A meta-analysis was performed with a random effects model in the Revman 5.4.1software using the mean difference (MD) of cycle threshold (Ct) values.

RESULTS

Of 1653 articles, 9 with a high methodological quality were included. A meta-analysis indicated that 1% Povidone-iodine (PVP-I) was an effective mouthwash for reducing the SARS-COV-2 viral load [MD 3.61 (95% confidence interval 1.03, 6.19)]. Cetylpyridinium chloride (CPC) [MD 0.61 (95% confidence interval -1.03, 2.25)] and Chlorhexidine gluconate (CHX) [MD -0.04 95% confidence interval (-1.20, 1.12)] were not effective against SARS-COV-2.

CONCLUSION

Using mouthwashes containing PVP-I may be recommended for reducing the SARS-COV-2 viral load in the oral cavity of patients before and during dental procedures, while the evidence is not sufficient for such effects for CPC and CHX-containing mouthwashes.

The anti-SARS-CoV-2 effect and mechanism of Chiehyuan herbal oral protection solution

The Chiehyuan herbal oral protection solution (GB-2) is a herbal mixture commonly utilized in Taiwan for combating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as per traditional Chinese medicine practices. This study assessed the clinical impact of GB-2 through prospective clinical trials. With twice-daily use for a week, GB-2 was shown to diminish the expression of angiotensin-converting enzyme 2 (ACE2) in oral mucosal cells. Moreover, after two weeks of use, it could reduce transmembrane protease, serine 2 (TMRPSS2) expression in these cells. Additionally, in vitro experiments demonstrated that GB-2 lessened the entry efficiency of the Omicron, L452R-D614G, T478K-D614G, and L452R-T478K-D614G variants of the SARS-CoV-2 pseudotyped lentivirus. It also impeded the interaction between ACE2 and the receptor-binding domain (RBD) presenting N501Y-K417N-E484A-G339D-Q493R-G496S-Q498R and L452R-T478K mutations. Glycyrrhizic acid, a major compound in GB-2, also hindered the entry of the Omicron variant (BA.1) of the SARS-CoV-2 pseudotyped lentivirus by obstructing the binding between ACE2 and the RBD presenting the N501Y-K417N-E484A-G339D-Q493R-G496S-Q498R mutation. To sum up, these findings suggest that GB-2 can decrease ACE2 and TMPRSS2 expression in oral mucosal cells. Both glycyrrhizic acid and GB-2 were found to reduce the entry efficiency of the Omicron variant (BA.1) of the SARS-CoV-2 pseudotyped lentivirus and block the binding between ACE2 and the RBD with the N501Y-K417N-E484A-G339D-Q493R-G496S-Q498R mutation. This evidence implies that GB-2 might be a potential candidate for further study as a preventative measure against SARS-CoV-2 infection.

Effects of Chlorhexidine and Povidone-Iodine on the SARS-CoV-2 Load: A Systematic Review and Meta-analysis

The efficacy of mouthwash for reducing the viral load in patients with the novel coronavirus disease 2019 (COVID-19) remains unclear. This systematic review and meta-analysis comprehensively examined the effects of chlorhexidine (CHX) and povidone-iodine (PVP-I) on the viral load in patients with COVID-19. We performed methodological analysis, systematic review, and meta-analysis of included studies using the Comprehensive Meta-analysis Software. PubMed, EMBASE, Cochrane Library, and ProQuest were searched from December 1, 2019, to December 2, 2021. In total, we included 10 studies of 1,339 patients with COVID-19. Compared with the control group, both CHX and PVP-I significantly reduced the number of negative reverse-transcription polymerase chain reaction (RT-PCR) results (p<0.001) among COVID-19 patients. The CHX and PVP-I were effective on reducing the number of negative RT-PCR results in COVID-19 patients. Additional studies using adequate randomization methods and larger samples are warned.

COVID-19 pandemic sheds a new research spotlight on antiviral potential of essential oils - A bibliometric study

Background

Essential oils are thought as potential therapies in managing coronavirus disease 2019 (COVID-19). Many researchers have put their efforts to tackle the pandemic by exploring antiviral candidates which consequently changes the research landscape. Herein, we aimed to assess the effect of COVID-19 pandemic toward the landscape of essential oil research.

Methods

This study employed bibliometric analysis based on the metadata of published literature indexed in the Scopus database. The search was performed on December 15th, 2022 by using keyword 'essential oil' and its synonyms. We grouped the data based on publication year; pre-COVID-19 (2014-2019) and during COVID-19 (2020-2024, some studies have been published earlier). Further, we separated the COVID-19-focused research from COVID-19 (2020-2024) by introducing a new keyword 'COVID-19' during the search. All metadata were processed using VoSviewer and Biblioshiny for network visualization analysis. Selections of frequently occurring keywords, clusters of keyword co-occurrence, and the list of most impactful papers were performed by two independent reviewers.

Results

Metadata from a total of 35,262 publications were included for bibliometric analysis, comprised of three groups of datasets namely pre-COVID-19 (n = 18,670), COVID-19 (n = 16,592), and COVID-19-focused (n = 281). Five research topics clusters were found from pre-COVID-19 dataset, eight - from COVID-19 dataset, and nine - from COVID-19-focused dataset. COVID-19 cluster containing the keyword 'antiviral' emerged in the COVID-19 dataset, whereas none of the previous research topic clusters contained the keyword 'antiviral'. Antiviral, angiotensin-converting enzyme 2 (ACE2) inhibitory, and anti-inflammation activities were among the top occurring keywords in studies covering both essential oil and COVID-19. Studies on essential oil used for managing COVID-19 were most reported by authors from the United States (documents = 37, citations = 405), Australia (documents = 16, citations = 115) and Italy (documents = 23, citations = 366).

Conclusion

A significant increase was found during COVID-19 pandemic for publications covering essential oil themes, but only a small portion was occupied by COVID-19 research. The COVID-19 pandemic does not alter the ongoing progress of essential oil research but rather offers a new spotlight on the antiviral potential of essential oils. Hence, the COVID-19 pandemic has provided an opportunity to investigate deeper the antiviral potential of essential oils.

Tenofovir antiviral drug solubility enhancement with β-cyclodextrin inclusion complex and in silico study of potential inhibitor against SARS-CoV-2 main protease (Mpro)

Tenofovir (TFR) is an antiviral drug commonly used to fight against viral diseases infection due to its good potency and high genetic barrier to drug resistance. In physiological conditions, TFR is less water soluble, more unstable, and less permeable, limiting its effective therapeutic applications. In addition to their use in treating the Coronavirus disease 2019 (COVID-19), cyclodextrins (CDs) are also being used as a molecule to develop therapies for other diseases due to its enhance solubility and stability. This study is designed to synthesize and characterization of β-CD:TFR inclusion complex and its interaction against SARS-CoV-2 (M^Pro) protein (PDB ID;7cam). Several techniques were used to characterize the prepared β-CD:TFR inclusion complex, including UV-Visible, FT-IR, XRD, SEM, TGA, and DSC, which provided appropriate evidence to confirm the formation. A 1:1 stoichiometry was determined for β-CD:TFR inclusion complex in aqueous medium from UV-Visible absorption spectra by using the Benesi-Hildebrand method. Phase solubility studies proposed that β-CD enhanced the excellent solubility of TFR and the stability constant was obtained at 863 ± 32 M^-1. Moreover, the molecular docking confirmed the experimental results demonstrated the most desirable mode of TFR encapsulated into the β-CD nanocavity via hydrophobic interactions and possible hydrogen bonds. Moreover, TFR was validated in the β-CD:TFR inclusion complex as potential inhibitors against SARS-CoV-2 main protease (M^pro) receptors by using in silico methods. The enhanced solubility, stability, and antiviral activity against SARS-CoV-2 (M^Pro) suggest that β-CD:TFR inclusion complexes can be further used as feasible water-insoluble antiviral drug carriers in viral disease infection.

Effect of the povidone iodine, hypertonic alkaline solution and saline nasal lavage on nasopharyngeal viral load in COVID-19

OBJECTIVE

The present study aimed to investigate the in vivo activity of nasal irrigation (NI) with saline, NI with povidone-iodine (PVP-I) 1%, NI with a mix of hypertonic alkaline and PVP-I 1% against Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2).

DESIGN

This study was a prospective randomised clinical trial.

SETTING

A multicenter study involving tertiary care centres.

PARTICIPANTS

The study included adult outpatients whose qualitative SARS-CoV-2 RT-PCR tests in nasopharyngeal swabs were positive. One hundred twenty patients were divided into four equal groups. Standard COVID-19 treatment was given to Group 1, NI containing saline was added to patients' treatment in Group 2, NI containing 1% PVP-I solution was added to patients' treatment in Group 3, and NI containing 1% PVP-I solution and the hypertonic alkaline solution was added to patients' treatment in Group 4.

MAIN OUTCOME MEASURES

On the first day of diagnosis (Day 0), nasopharyngeal swab samples were taken, on the third and fifth days the nasopharyngeal viral load (NVL) reduction in quantitative RT-PCR test was calculated.

RESULTS

Between the zeroth to third days and zeroth to fifth days, the NVL reduction was significant in all groups (p < .05). In paired comparisons of groups, the NVL decrease in Group 4 in the first 3 days was significantly lower than all groups (p < .05). The NVL decrease in Groups 3 and 4 in the first 5 days were significantly lower than Group 1 (p < .05).

CONCLUSION

This study revealed that the use of NI of 1% PVP-I and the hypertonic alkaline solution mixture was more effective in reducing NVL.

Pilot study of aerosols visualized and evaluated in a radiotherapy room

Health care institutions provide prevention strategies for coronavirus disease 2019 and non-infectious disease care. We investigated the characteristics of patient contamination in a radiotherapy room by examining the trajectory and number of airborne particles in the air when talking and coughing occurred and clarified the actual state of contamination in this closed space. Aerosols were visualized and evaluated in the vertical height and head-to-tail width directions when the participant was lying on the radiotherapy tabletop. Aerosol reach was significantly greater for loud voice and coughing both at vertical height and the head-to-tail width direction. The size and number of particles around the radiotherapy tabletop were also visualized and evaluated in the radiotherapy room. The radiotherapy staff who were in the presence of the participant sometimes had many particles adhering to their facial area; particle adhesion to the staff was dominated by small size particles. Particle adherence to the irradiation device surface near the ceiling had particles larger than 1 mm. Tabletop particles tended to have a wider size range, including bigger sizes and a larger count compared to the surrounding floor. The 0.7-m radius distance from the participant's mouth tended to be highly contaminated, and the smaller the particle size, the farther it reached. The capacity to estimate areas prone to contamination can be used to predict infection of other patients and medical staff in a radiotherapy room.

Anticancer potential of curcumin-cyclodextrin complexes and their pharmacokinetic properties

Cancer is one of the most common diseases throughout the world, with many treatment modalities currently being used, and new treatment strategies being sought. Most chemotherapeutic molecules have shown extensive toxicity for normal cells, which leads to severe adverse effects. Chemotherapy may also lead to drug resistance, which is one of the major obstacles to the clinical treatment of cancer. Curcumin, a polyphenolic natural compound, has long been considered a therapeutic molecule for a variety of diseases and possesses anti-cancer, anti-oxidant, and anti-inflammatory properties. However, its use is limited due to its hydrophobic nature, poor solubility in water at acidic or neutral pH, and limited bioavailability at the tumor site. Cyclodextrin complexes of curcumin increase curcumin's water solubility, as well as its physicochemical stability to hydrolysis and photochemical decomposition. The most common type of cyclodextrin used for pharmaceutical preparations is β-cyclodextrin. This review focuses on different curcumin-cyclodextrin formulations and compares their pharmacokinetic parameters and efficacy.

Efectividad de enjuagues bucales contra virus de la familia coronavirus

La aparición del virus Sars-CoV-2 y la enfermedad Covid-19 han provocado un estado de emergencia en el sistema de salud. Teniendo en cuenta el potencial de la saliva como material contaminante, la práctica odontológica fue una de las áreas que se vio afectada debido al uso de instrumentos que pueden esparcir aerosoles y salpicaduras que contienen microorganismos hacia el medio ambiente. Por esta razón, conociendo su potencial en la inactivación de patógenos, se propuso la utilización de enjuagues bucales en la práctica clínica previo a la realización de procedimientos dentales, sin embargo la evidencia no es clara respecto a su efectividad. Objetivo. Establecer el estado de evidencia actual del efecto de los enjuagues bucales sobre los coronavirus que se encuentran en cavidad. Métodos. Se realizó una revisión sistemática siguiendo todos los parámetros descritos en las DirectricesPRISMA basada en información obtenida en los buscadores Science direct, Pubmed y Dentistry and Oral Science Source. Los criterios de selección incluyeron estudios in vivo e in vitro de texto completo que evidenciaron la efectividad del enjuague bucal contra coronavirus. Resultados. Se obtuvieron 90 artículos, de los cuales sólo 12 cumplían con los criterios de inclusión,8 in vitro y 4 in vivo, que fueron sometidos a la evaluación de calidad metodológica utilizando la lista de verificación de evaluación crítica del JBI.  Conclusiones. Los resultados sugieren que la povidona yodada es efectiva para la inactivación del virus Sars-coV-2 en todas sus concentraciones.

When the clock ticks wrong with COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a member of the coronavirus family that causes the novel coronavirus disease first diagnosed in 2019 (COVID-19). Although many studies have been carried out in recent months to determine why the disease clinical presentations and outcomes can vary significantly from asymptomatic to severe or lethal, the underlying mechanisms are not fully understood. It is likely that unique individual characteristics can strongly influence the broad disease variability; thus, tailored diagnostic and therapeutic approaches are needed to improve clinical outcomes. The circadian clock is a critical regulatory mechanism orchestrating major physiological and pathological processes. It is generally accepted that more than half of the cell-specific genes in any given organ are under circadian control. Although it is known that a specific role of the circadian clock is to coordinate the immune system's steady-state function and response to infectious threats, the links between the circadian clock and SARS-CoV-2 infection are only now emerging. How inter-individual variability of the circadian profile and its dysregulation may play a role in the differences noted in the COVID-19-related disease presentations, and outcome remains largely underinvestigated. This review summarizes the current evidence on the potential links between circadian clock dysregulation and SARS-CoV-2 infection susceptibility, disease presentation and progression, and clinical outcomes. Further research in this area may contribute towards novel circadian-centred prognostic, diagnostic and therapeutic approaches for COVID-19 in the era of precision health.

Efficacy of Mouth Rinses and Nasal Spray in the Inactivation of SARS-CoV-2: A Systematic Review and Meta-Analysis of In Vitro and In Vivo Studies

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) is a global and evolving pandemic associated with heavy health and financial burdens. Considering the oral cavity as the major reservoir for SARS-CoV-2, a systematic review and meta-analysis were conducted to assess the efficacy of mouth rinses and nasal sprays in reducing the salivary viral load of SARS-CoV-2. All in vivo and in vitro studies that assessed the virucidal efficacy of mouth rinses and nasal sprays against SARS-CoV-2 and were published in the English language from December 2019 to April 2022 were considered for analyses. Special Medical Subject Headings terms were used to search Pubmed, Scopus, Embase Ovid, and Web of Science databases. The toxicological data reliability assessment tool (ToxRToool) was used to assess the quality of the included studies. Thirty-three studies (11 in vivo and 22 in vitro) were deemed eligible for inclusion in this analysis. Results of the pooled data showed that povidone-iodine is the most efficacious intervention in vivo in terms of reducing the SARS-CoV-2 salivary viral load, followed by chlorhexidine. The mean difference in the viral load was 86% and 72%, respectively. Similarly, povidone-iodine was associated with the highest log₁₀ reduction value (LRV) in vitro, followed by cetylpyridinium chloride, (LRV = 2.938 (p < 0.0005) and LRV = 2.907 (p = 0.009), respectively). Povidone-iodine-based oral and nasal preparations showed favourable results in terms of reducing SARS-CoV-2 viral loads both in vivo and in vitro. Considering the limited number of patients in vivo, further studies among larger cohorts are recommended.

Oral Lesions Associated with COVID-19 and the Participation of the Buccal Cavity as a Key Player for Establishment of Immunity against SARS-CoV-2

BACKGROUND

Some oral lesions have been described in patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2); the possibility has been raised that the buccal lesions observed in patients with the coronavirus disease 2019 (COVID-19) are due to this virus and the patient's systemic condition. The aim of this review was to integrate the knowledge related to the oral lesions associated with COVID-19 and the participation of the buccal cavity in the establishment of immunity against SARS-CoV-2.

METHODS

A literature search on the manifestations of buccal lesions from the beginning of the pandemic until October 2021 was carried out by using the PubMed database. A total of 157 scientific articles were selected from the library, which included case reports and reports of lesions appearing in patients with COVID-19.

RESULTS

Oral lesions included erosions, ulcers, vesicles, pustules, plaques, depapillated tongue, and pigmentations, among others. The oral cavity is a conducive environment for the interaction of SARS-CoV-2 with the mucosal immune system and target cells; direct effects of the virus in this cavity worsen the antiviral inflammatory response of underlying oral disorders, immunodeficiencies, and autoimmunity primarily.

CONCLUSIONS

The oral cavity is an accessible and privileged environment for the interaction of SARS-CoV-2 with the mucosal immune system and target cells; the direct effects of the virus in this cavity worsen the antiviral inflammatory response of underlying oral disorders, in particular those related to immunodeficiencies and autoimmunity.

Diffusion of Vanadium Ions in Artificial Saliva and Its Elimination from the Oral Cavity by Pharmacological Compounds Present in Mouthwashes

In this study, diffusion coefficients of ammonium vanadate at tracer concentrations in artificial saliva with and without sodium fluoride, at different pH values, were measured using an experimental model based on the Taylor dispersion technique. Ternary mutual diffusion coefficients (D11, D22, D12, and D21) for four aqueous systems {NH4VO3 (component 1) + β-cyclodextrin (β-CD) (component 2),} {NH4VO3 (component 1) + β-cyclodextrin (HP-β-CD) (component 2)}, {NH4VO3 (component 1) + sodium dodecyl sulphate (SDS) (component 2)} and {NH4VO3 (component 1) + sodium hyaluronate (NaHy) (component 2)} at 25.00 °C were also measured by using the same technique. These data showed that diffusion of ammonium vanadate was strongly affected in all aqueous media studied. Furthermore, a significant coupled diffusion of this salt and β-CD was observed through the non-zero values of the cross-diffusion coefficients, D12, allowing us to conclude that there is a strong interaction between these two components. This finding is very promising considering the removal, from the oral cavity, of vanadium resulting from tribocorrosion of Ti-6Al-4V prosthetic devices.

Is Chlorhexidine in Dentistry an Ally or a Foe? A Narrative Review

Chlorhexidine has been one of the most effective and popular antiseptic substances used in medicine for decades. In dentistry, it has been used in endodontics, periodontology, surgery, and general dentistry. It is also widely used daily by patients in mouth rinses, gels, or toothpastes. Because of its multiple uses, we should follow all types of research reporting its potential adverse effects. This article aims to review the most up-to-date studies regarding chlorhexidine and its possible side effects, in the period of the SARS-CoV-2 pandemic, as the use of different antiseptic substances has rapidly increased.

Efficacy of Pre-Procedural Mouthwashes against SARS-CoV-2: A Systematic Review of Randomized Controlled Trials

The oral mucosa is one of the first sites to be affected by the SARS-CoV-2. For this reason, healthcare providers performing aerosol-generating procedures (AGPs) in the oral cavity are at high risk of infection with COVID-19. The aim of this systematic review is to verify whether there is evidence in the literature describing a decrease in the salivary viral load of SARS-CoV-2 after using different mouthwashes. An electronic search of the MEDLINE database (via PubMed), Web of Science, SCOPUS, and the Cochrane library database was carried out. The criteria used were those described by the PRISMA® Statement. Randomized controlled trial studies that have used mouthwashes as a form of intervention to reduce the viral load in saliva were included. The risk of bias was analyzed using the Joanna Briggs Institute Critical Appraisal Tool. Ultimately, eight articles were included that met the established criteria. Based on the evidence currently available in the literature, PVP-I, CHX and CPC present significant virucidal activity against SARS-CoV-2 in saliva and could be used as pre-procedural mouthwashes to reduce the risk of cross-infection.

Virucidal Activity of Different Mouthwashes against the Salivary Load of SARS-CoV-2: A Narrative Review

The saliva of COVID-19-confirmed patients presents a high viral load of the virus. Aerosols generated during medical and dental procedures can transport the virus and are a possible causative agent of cross-infection. Since the onset of the pandemic, numerous investigations have been attempting to mitigate the risk of transmission by reducing the viral load in saliva using preprocedural mouthwashes. This study aims to review the most up-to-date in vitro and in vivo studies investigating the efficacy of different mouthwashes on reducing the salivary viral load of SARS-CoV-2, giving particular attention to the most recent randomized control trials published.

Povidone-Iodine as a Pre-Procedural Mouthwash to Reduce the Salivary Viral Load of SARS-CoV-2: A Systematic Review of Randomized Controlled Trials

The use of pre-procedural rinses has been investigated to reduce the number of viral particles and bacteria in aerosols, potentially decreasing the risk of cross-infection from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during medical and dental procedures. This review aims to confirm whether there is evidence in the literature describing a reduction in salivary load of SARS-CoV-2 when povidone-iodine (PVP-I) is used as a pre-intervention mouthwash. An search of the MEDLINE, Embase, SCOPUS, and the Cochrane library databases was conducted. The criteria used followed the PRISMA® Statement guidelines. Randomized controlled trials investigating the reduction of salivary load of SARS-CoV-2 using PVP-I were included. Ultimately, four articles were included that met the established criteria. According to the current evidence, PVP-I is effective against SARS-CoV-2 in saliva and could be implemented as a rinse before interventions to decrease the risk of cross-infection in healthcare settings.

In silico screening of potent inhibitors against COVID-19 key targets from a library of FDA-approved drugs

Coronavirus disease (COVID-19) is an emerging pandemic that threatens the world since the early days of 2020. Development of vaccines or new drugs against COVID-19 comprises several stages of investigation including efficacy, safety, and approval studies. A shortcut to this delicate pathway is computational-based analysis of FDA-approved drugs against assigned molecular targets of the coronavirus. In this study, we virtually screened a library of FDA-approved drugs prescribed for different therapeutic purposes against versatile COVID-19 specific proteins which are crucial for the virus life cycle. Three antibiotics in our screening polymyxin B, bafilomycin A, and rifampicin show motivating binding stability with more than one target of the virus. Another category of tested drugs is oral antiseptics of mouth rinsing solutions that unexpectedly exhibited significant affinity to the target proteins employed by the virus for attachment and cell internalization. Other OTC drugs widely used and tested in our study are heartburn drugs and they show no significant binding. We tested also some other drugs falling under the scope of investigation regarding interference with a degree of severity of COVID-19 like angiotensin II blockers used as antihypertensive, and our study suggests a therapeutic rather than predisposing effect of these drugs against COVID-19.

ANTIVIRAL EFFECT OF MOUTHWASHES AGAINST SARS-COV-2: A SYSTEMATIC REVIEW

Objective

This systematic review aimed to evaluate the antiviral effect of mouthwashes against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Material and methods

An electronic search was performed on PubMed, Scopus, Web of Science, Cochrane Library, LILACS, ProQuest, and Google Scholar, and was complemented by a manual search. Both clinical and in vitro studies that focused on the antiviral effect of mouthwashes against SARS-CoV-2 were included. Risk of bias assessment was performed only on the clinical studies using the RoB-2 and ROBINS-I tools.

Results

A total of 907 records were found; after initial selection by title and abstract, 33 full-text articles were selected to be evaluated for eligibility. Finally, a total of 27 studies were included for the qualitative synthesis, including 16 in vitro studies and 11 clinical trials. Antiviral effects were evaluated separately for the in vitro and clinical studies. In vitro studies included mouthwashes containing hydrogen peroxide, chlorhexidine digluconate, povidone-iodine, essential oils, cetylpyridinium chloride, and other compounds; in vivo studies included mouthwashes containing hydrogen peroxide, chlorhexidine digluconate, povidone-iodine, cetylpyridinium chloride, essential oils, chlorine dioxide, β-cyclodextrin-citrox, and sorbitol with xylitol. Povidone-iodine, cetylpyridinium chloride, and essential oils were effective in vitro, while hydrogen peroxide, chlorhexidine digluconate, povidone-iodine, cetylpyridinium chloride, β-cyclodextrin-citrox, and sorbitol with xylitol were effective in vivo. Unclear or high risk of bias was found for almost all clinical studies, and only one study presented with a low risk of bias. No further quantitative analysis was performed.

Conclusion

Although povidone-iodine, cetylpyridinium chloride, and essential oils may be an alternative to reduce the viral load in vitro and in vivo, more studies are needed to determine the real antiviral effect of these different mouthwashes against SARS-CoV-2.

This work was not funded. The protocol was registered in PROSPERO (identification number: CRD42021236134).

Cetylpyridinium chloride promotes disaggregation of SARS-CoV-2 virus-like particles

Background

SARS-CoV-2 is continuously disseminating worldwide. The development of strategies to break transmission is mandatory.

Aim of the study

To investigate the potential of cetylpyridinium chloride (CPC) as a viral inhibitor.

Methods

SARS-CoV-2 Virus Like-Particles (VLPs) were incubated with CPC, a potent surfactant routinely included in mouthwash preparations.

Results

Concentrations of 0.05% CPC (w/v) commonly used in mouthwash preparations are sufficient to promote the rupture of SARS-CoV-2 VLP membranes.

Conclusion

Including CPC in mouthwashes could be a prophylactic strategy to keep SARS-CoV-2 from spreading.

COVID-19 Pandemic and Periodontal Practice: The Immunological, Clinical, and Economic Points of View

The recent global health problem, COVID-19, has had far-reaching impacts on lifestyles. Although many effective WHO-approved vaccines have been produced that have reduced the spread and severity of the disease, it appears to persist in humans for a long time and possibly forever as everyday it turns out to have new mutations. COVID-19 involves the lungs and other organs primarily through cytokine storms, which have been implicated in many other inflammatory disorders, including periodontal diseases. COVID-19 is in a close association with dental and periodontal practice from two respects: first, repeated mandatory lockdowns have reduced patient referrals to dentists and limited the dental and periodontal procedures to emergency treatments, whereas it is important to recognize the oral manifestations of COVID-19 as well as the influence of oral and periodontal disease on the severity of COVID-19. Second, dentistry is one of the high-risk professions in terms of close contact with unmasked individuals, necessitating redefining the principles of infection control. The pressures of the economic recession on patients as well as dentists add to the difficulty of resuming elective dental services. Therefore, this study is divided into two parts corresponding to what mentioned above: the first part examines the clinical and immunological associations between COVID-19 and periodontal and oral diseases, and the second part delineates the measures needed to control the disease transmission in dental clinics as well as the economic impact of the pandemic era on dental services.

Nasopharyngeal and oropharyngeal rinses with neutral electrolyzed water prevents COVID-19 in front-line health professionals: A randomized, open-label, controlled trial in a general hospital in Mexico City

The worldwide efforts that healthcare professionals are making in the COVID-19 pandemic is well known, and the high risk of illness and death that front-line staff experience on a daily basis is a reality, despite well-defined protocols for the use of personal protective equipment. In addition, it is well known that vaccination is still faraway to be achieved worldwide and that new variants are emerging, thus additional protective measures must be explored. A prospective open-label randomized controlled clinical trial was performed on front-line medical staff from the Dr. Enrique Cabrera General Hospital in México City to evaluate the effectiveness of nasopharyngeal and oropharyngeal rinses with a neutral electrolyzed water, known as SES, to reduce the risk of COVID-19 disease among front-line, not vaccinated medical staff. A total of 170 volunteers were enrolled and equally divided in a control group and SES group. All members of the trial wore the adequate personal protection equipment at all times while performing their duties, as required by standard COVID-19 safety protocols. Additionally, the SES group participants followed a prophylactic protocol with SES (oral and nasal rinses, three times a day for 4 weeks). All participants were monitored for COVID-19 symptoms and disease in a time-frame of 4 weeks and the incidence of illness per group was registered. The relative risk of disease, associated with each treatment was calculated. The presence of COVID-19-positive cases, in the group that received the nasal and oral rinses with SES was 1.2%, while in the group that did not do the SES rinses (control group), it was 12.7% (P=0.0039 and RR=0.09405; 95% CI of 0.01231-0.7183). The prophylactic protocol was demonstrated as a protective factor, in more than 90%, for developing the disease, and without adverse effects. Nasal and oral rinses with SES may be an efficient alternative to reinforce the protective measures against COVID-19 disease and should be further investigated. The present clinical trial was retrospectively registered in the Cuban public registry of clinical trials (RPCEC) database (March 16, 2021; PREVECOVID-19: RPCEC00000357).

Population-based virucidal phthalocyanine gargling/rinsing protocol to reduce the risk of coronavirus disease-2019: a community trial

Aim

In this community trial, the objective was to evaluate the incidence of coronavirus disease-2019 (COVID-19) cases in two similar communities in three distinct phases: 1 (before the intervention), 2 (during the intervention), and 3 (after the intervention).

Methods

The test community received the oral antiseptic intervention (experimental), while the control community did not. The official information agency ("Statewise System for Data Analysis") provided the number of confirmed COVID-19 cases. Data were analyzed according to the three phases per epidemiological week (epi) using the R Core Team (2021) program. The relative risk and 95% confidence intervals between the cumulative incidence values of the test and control communities were calculated for each period. In the test community, a total of 995 residents over 10 years of age received two bottles containing 600 ml of mouthwash containing antiviral phthalocyanine derivative (APD). The participants were asked to gargle/rinse with of 5 mL of the mouthwash containing ADP 3 to 5 times a day, for 1 min, until the bottles were empty.

Results

In phases 1 and 3, the disease risk between the two communities did not differ significantly (p>0.05), while in phase 2, the disease risk was 54% lower in the test community than in the control community.

Conclusion

The use of the APD mouthwash protocol seems to reduce the COVID-19 incidence at the population level, and further studies are needed to confirm its protective effect under more precisely controlled conditions.

SARS-CoV-2: Overview and Its Impact on Oral Health

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its virulent variants causing coronavirus disease 2019 (COVID-19) COVID-19 has spread rapidly worldwide, and is highly contagious. A comprehensive search was conducted for the most current published information about SARS-CoV-2, COVID-19, and oral health. Clinical studies, case reports, in vivo studies, and any current published evidence on SARS-CoV-2 and COVID-19 were included in this review. Survival against SARS-CoV-2 infection may be partially dependent on periodontal health, good oral hygiene, and access to dental care. Optimum oral health, maintaining good systemic health, and elimination of smoking habits may be beneficial for the prevention and management of COVID-19 infections.

Periodontal Management during COVID-19 Pandemic: Mini Review

A few cases of pneumonia were reported by Wuhan Municipal Health Commission in Wuhan, Hubei Province, Republic of China and this mysterious pneumonia was recognized as novel coronavirus disease (COVID-19) in the course of time on 31 December 2019. Based on the literature knowledge, COVID-19 outbreak was came into existence through an animal-to-human transmission, then continued human-to-human diffusion. Especially dentists among the medical professionals are at high-risk group of SARS-CoV-2 virus contamination because of several routine dental procedures having the risk to convey the SARS-CoV-2 virus via droplets and close contact. In this mini review, it was aimed to give information about patient management during COVID-19 pandemic for dental practitioners, periodontologists and dental hygienists.

Beneficial effects of a mouthwash containing an antiviral phthalocyanine derivative on the length of hospital stay for COVID-19: randomised trial

The risk of contamination and dissemination by SARS-CoV-2 has a strong link with nasal, oral and pharyngeal cavities. Recently, our research group observed the promising performance of an anionic phthalocyanine derivative (APD) used in a mouthwash protocol without photoexcitation; this protocol improved the general clinical condition of patients infected with SARS-CoV-2. The present two-arm study evaluated in vitro the antiviral activity and cytotoxicity of APD. Additionally, a triple-blind randomized controlled trial was conducted with 41 hospitalized patients who tested positive for COVID-19. All the included patients received World Health Organization standard care hospital treatment (non-intensive care) plus active mouthwash (experimental group AM/n = 20) or nonactive mouthwash (control group NAM/n = 21). The adjunct mouthwash intervention protocol used in both groups consisted one-minute gargling/rinsing / 5 times/day until hospital discharge. Groups were compared considering age, number of comorbidities, duration of symptoms prior admission and length of hospital stay (LOS). The associations between group and sex, age range, presence of comorbidities, admission to Intensive care unit (ICU) and death were also evaluated. The in vitro evaluation demonstrated that APD compound was highly effective for reduction of SARS-CoV-2 viral load in the 1.0 mg/mL (99.96%) to 0.125 mg/mL (92.65%) range without causing cytotoxicity. Regarding the clinical trial, the median LOS of the AM group was significantly shortened (4 days) compared with that of the NAM group (7 days) (p = 0.0314). Additionally, gargling/rinsing with APD was very helpful in reducing the severity of symptoms (no ICU care was needed) compared to not gargling/rinsing with APD (28.6% of the patients in the NAM group needed ICU care, and 50% of this ICU subgroup passed way, p = 0.0207). This study indicated that the mechanical action of the protocol involving mouthwash containing a compound with antiviral effects against SARS-CoV-2 may reduce the symptoms of the patients and the spread of infection. The use of APD in a mouthwash as an adjuvant the hospital COVID-19 treatment presented no contraindication and reduced the hospital stay period.

Trial registration: The clinical study was registered at REBEC—Brazilian Clinical Trial Register (RBR-58ftdj).

COVID-19 and dental workers: The Italian Society of Periodontology and Implantology (SIdP) survey

Objectives

To evaluate the proportion of COVID‐19 infections among a population of Italian Dental workers across different geographical area of Italy and to analyze the impact of both the preventive measures/strategies adopted and the psychological influences.

Subjects and Methods

The current cross‐sectional survey was administered with a web‐based form. To be eligible for the study, participants had to be 18 years and being dentists or dental hygienists members of the Italian Society of Periodontology and Implantology (SIdP). A 23‐item questionnaire concerning positiveness to COVID‐19, clinical strategies and psychological attitude within the pandemic was administered. Sub‐group analysis was conducted according to geographical macro‐area.

Results

A total of 790 dentists and dental hygienists were included. A total of 4.7% participants developed a positive diagnosis to COVID‐19. The Northwest of Italy experienced almost double of COVID‐19‐positive participants (p < 0.05). Preoperatory mouthwashes together with natural air change/ventilation were the most frequent approaches used to prevent COVID‐19 outbreak. Positive and proactive attitudes were predominant among participants. Only a reduced proportion feels some concerns for the future.

Conclusions

Prevalence of positive COVID‐19 among dental workers in Italy was double in Northwest area in comparison with the whole country proportion. Preventive strategies comprise mainly ultrasound reduction and preoperative mouthwashes.

COVID-19 risks and extra-protective measures practised among Nigerian orthodontists and orthodontic residents

Background and Aims

There is a high possibility of transmitting the coronavirus (severe acute respiratory syndrome coronavirus 2) in the orthodontic clinic because orthodontists and their patients are in very close contact when orthodontic care is being given. The aim of this study was to evaluate the knowledge and perception of Nigerian orthodontists and orthodontic residents about the risks of COVID-19 as well as the extra-protective infection control measures that need to be taken.

Materials and Methods

This was a descriptive, cross-sectional study. The questionnaires were distributed and retrieved from consenting participants through an online platform. The questionnaires were analysed using the Statistical Package for the Social Sciences software version 23. The results were presented in tables and charts.

Results

Out of a total of 90 members on the association's WhatsApp group as at the time the study was being conducted, a total of 48 respondents participated in this study. There were more females (60.4%) than males. Majority (97.9%) of the respondents agreed/strongly agreed that an infected patient could infect the orthodontic clinic staff members with COVID-19 while most were of the view that debonding (95.8%) and retainer delivery (70.8%) posed a risk for spread of the virus. More than half of the respondents (52.1%) considered it necessary to change N95 masks after each patient as an extra-protective measure against COVID-19.

Conclusions

Majority of the respondents knew about the risks that COVID-19 posed to different aspects of orthodontic practice and were also knowledgeable about some of the extra-protective measures that they should take. There is a need to improve the knowledge of the participants concerning the use of appropriate mouth rinses to reduce the risks of transmission of COVID-19 in the dental/orthodontic clinic.

Evidence-based Recommendations on Periodontal Practice and the Management of Periodontal Patients During and After the COVID-19 Era: Challenging Infectious Diseases Spread by Airborne Transmission

Background:

Periodontal care, which was completely suspended during the peak of the SARS-Cov-2 pandemic and was delayed and recurrently discontinued during the succeeding waves, must be safely provided in the COVID-19 era.

Objectives:

The study aimed to provide recommendations on periodontal practice, optimizing safety, ergonomics, and economic resources, and the management of periodontal patients, ensuring continuity, timing, and effectiveness of periodontal care in the COVID-19 era.

Methods:

Reported protocols for the dental practice in the context of the COVID-19 and current evidence on periodontitis treatment and prevention were reviewed.

Results:

Evidence-based recommendations on contamination control and ergonomic improvements for periodontal practice and the management of periodontal patients challenging COVID-19 and airborne infectious diseases have been provided.

Conclusion:

Due to the economic, ergonomic, and ethical concerns raised by limited periodontal care due to the SARS-Cov-2 pandemic, and awareness of other emerging airborne transmitted infections, the periodontal practice should integrate measures minimizing airborne cross-infections and optimizing time-space and economic resources. The management of periodontal patients in the COVID-19 era should comprise less complex treatments and more comprehensive and definitive approaches, reducing emergencies, session length and number, and, concurrently, extending the recall and maintenance intervals. Moreover, it should implement prevention strategies through teledentistry tools and apps, improving periodontal awareness and self-care, and also through the self-reporting of periodontitis and periodontal risk assessment tools, performing both “population-based” and “high-risk” surveillance of periodontitis. Finally, it should enhance inter-professional collaboration, through telehealth networks, especially targeting subjects at high-risk of both periodontitis and systemic disorders, each of the two variously linked to COVID-19 onset and worsening.

Cyclodextrin-based Pickering emulsions: functional properties and drug delivery applications

Cyclodextrins (CDs) are biocompatible, cyclic oligosaccharides that are widely used in various industrial applications and have intriguing interfacial science properties. While CD molecules typically have low surface activity, they are capable of stabilizing emulsions by inclusion complexation of oil-phase components at the oil/water interface, which results in Pickering emulsion formation. Such surfactant-free formulations have gained considerable attention in recent years, owing to their enhanced physical stability, improved tolerability, and superior environmental compatibility compared to conventional, surfactant-based emulsions. In this review, we critically describe the latest insights into the molecular mechanisms involved in CD stabilization of Pickering emulsions, including covering practical aspects such as methods to prepare CD-based Pickering emulsions, lipid encapsulation, and relevant stability issues. In addition, the rheological and textural features of CD-based Pickering emulsions are discussed and particular attention is focused on promising examples for drug delivery, cosmetic, and nutraceutical applications. The functionality of currently developed CD-based Pickering emulsions is also summarised, including examples such as antifungal uses, and we close by discussing emerging possibilities to utilize the molecular encapsulation of CD-based emulsions for translational medicine applications in the antiviral and antibacterial spaces.

Cyclodextrins in the antiviral therapy

The main antiviral drug-cyclodextrin interactions, changes in physicochemical and physiological properties of the most commonly used virucides are summarized. The potential complexation of antiviral molecules against the SARS-Cov2 also pointed out the lack of detailed information in designing effective and general medicines against viral infections. The principal problem of the current molecules is the 3D structures of the currently active compounds. Improving the solubility or bioavailability of antiviral molecules is possible, however, there is no universal solution, and the complexation experiments dominantly use the already approved cyclodextrin derivatives. This review discusses the basic properties of the different cyclodextrin derivatives, their potential in antiviral formulations, and the prevention and treatment of viral infections. The biologically active new cyclodextrin derivatives are also discussed.

Versatile Nasal Application of Cyclodextrins: Excipients and/or Actives?

Cyclodextrins (CDs) are oligosaccharides widely used in the pharmaceutical field. In this review, a detailed examination of the literature of the last two decades has been made to understand the role of CDs in nasal drug delivery systems. In nasal formulations, CDs are used as pharmaceutical excipients, as solubilizers and absorption promoters, and as active ingredients due to their several biological activities (antiviral, antiparasitic, anti-atherosclerotic, and neuroprotective). The use of CDs in nasal formulations allowed obtaining versatile drug delivery systems intended for local and systemic effects, as well as for nose-to-brain transport of drugs. In vitro and in vivo models currently employed are suitable to analyze the effects of CDs in nasal formulations. Therefore, CDs are versatile pharmaceutical materials, and due to the continual synthesis of new CDs derivatives, the research on the new nasal applications is an interesting field evolving in the coming years, to which Italian research will still contribute.

Controversy around parabens: Alternative strategies for preservative use in cosmetics and personal care products

Parabens usage as preservatives in cosmetics and personal care products have been debated among scientists and consumers. Parabens are easy to production, effective and cheap, but its safety status remains controversial. Other popular cosmetics preservatives are formaldehyde, triclosan, methylisothiazolinone, methylchloroisothiazolinone, phenoxyethanol, benzyl alcohol and sodium benzoate. Although their high antimicrobial effectiveness, they also exhibit some adverse health effects. Lately, scientists have shown that natural substances such as essential oils and plant extracts present antimicrobial potential. However, their use in cosmetic is a challenge. The present review article is a comprehensive summary of the available methods to prevent microbial contamination of cosmetics and personal care products, which can allow reducing the use of parabens in these products.

Virucidal Activity of the Antiseptic Mouthwash and Dental Gel Containing Anionic Phthalocyanine Derivative: In vitro Study

AIM

This research suggested an in vitro virucidal action of a dental gel and a mouthwash with phthalocyanine derivative.

PURPOSE

The aim of this study was to report an in vitro study evaluating the virucidal capacity of mouthwash and dental gel containing anionic phthalocyanine derivate (APD).

METHODS

The research followed the recommendations of the National Health Surveillance Agency (ANVISA) and adapted methodology, described in the standards EN14776: 2015; ASTM E1053-11 and the Robert Koch Institute - RKI, in addition to good laboratory practices (GLP). The determination of the percentage of inactivation of the SARS-CoV-2 virus particles was carried out by imposing the viral solution in contact with the respective tested products, with intervals of 30 seconds, 1 and 5 minutes, with subsequent submission of the aliquots, recovered in cell culture microplates following virus titration using the TCID50 (50% Median Tissue Culture Infectious Dose).

RESULTS

The Mouthwash APD presented 90% of viral inactivation percentage, while the dental gel APD demonstrated 99.99% of viral inactivation.

CONCLUSION

In vitro analyses showed that mouthwash and dental gel APD can reduce the viability of SARS-CoV-2 virus particles.

The Use of Cyclodextrin or its Complexes as a Potential Treatment Against the 2019 Novel Coronavirus: A Mini-Review

Severe Acute Respiratory Syndrome Coronavirus 2 has spread rapidly since its discovery in December 2019 in the Chinese province of Hubei, reaching this day all the continents. This scourge is, unfortunately, in lineage with various dangerous outbreaks such as Ebola, Cholera, Spanish flu, American seasonal flu. Until today, the best solution for the moment remains prevention (Social distancing, hand disinfection, use of masks, partial or total sanitary containment, etc.); there is also the emergence of drug treatment (research and development, clinical trials, use on patients). Recent reviews emphasized the role of membrane lipids in the infectivity mechanism of SARS-COV-2. Cholesterol-rich parts of cell membranes serve as docking places of host cells for the viruses. Coronavirus 2 is a member of a virus family with lipid envelope that fuses with host cell through endocytosis, internalizing its components in the cell. In vitro cell models have shown that depletion of cholesterol by cyclodextrin, and particularly methyl beta cyclodextrin disturb the host cell membrane lipid composition this way, reducing the attachment of the virus to the protein receptors. This review aims to summarize the state of the art of research concerning the use of cyclodextrin or its complexes as a potential treatment against this new virus and update work already published.

Nanobased Platforms for Diagnosis and Treatment of COVID-19: From Benchtop to Bedside

Human respiratory viral infections are the leading cause of morbidity and mortality around the world. Among the various respiratory viruses, coronaviruses (e.g., SARS-CoV-2) have created the greatest challenge and most frightening health threat worldwide. Human coronaviruses typically infect the upper respiratory tract, causing illnesses that range from common cold-like symptoms to severe acute respiratory infections. Several promising vaccine formulations have become available since the beginning of 2021. Nevertheless, achievement of herd immunity is still far from being realized. Social distancing remains the only effective measure against SARS-CoV-2 infection. Nanobiotechnology enables the design of nanobiosensors. These nanomedical diagnostic devices have opened new vistas for early detection of viral infections. The present review outlines recent research on the effectiveness of nanoplatforms as diagnostic and antiviral tools against coronaviruses. The biological properties of coronavirus and infected host organs are discussed. The challenges and limitations encountered in combating SARS-CoV-2 are highlighted. Potential nanodevices such as nanosensors, nanobased vaccines, and smart nanomedicines are subsequently presented for combating current and future mutated versions of coronaviruses.

Safety protocols for dental care during the COVID-19 pandemic: the experience of a Brazilian hospital service

The coronavirus disease (COVID-19) has been prioritized in relation to other illnesses considered critical, such as cancer, cardiovascular diseases/stroke, diabetes, and autoimmune diseases. The management of patients with these diseases involves dental care to reduce systemic complications caused by odontogenic infections, and/or to treat oral manifestations of systemic comorbidities. In this regard, the dental care of these individuals must be guaranteed during the pandemic. Although a high risk of exposure to and catching of COVID-19 is expected to befall dental professionals, biosafety guidelines reduce the likelihood of infection. Thus, the current scenario poses challenges, and offers decision-making approaches and tools that facilitate the management of individuals with oral manifestations of chronic and/or critical diseases, using hospital-based services. This article presents an overview for hospital service providers who are at the forefront of COVID-19 care, including a secure protocol, and clinical guidelines based on the experience of the Hospital das Clínicas in Belo Horizonte, a public referral service, supported by the Brazilian National Health System.

Highly Active, Entirely Biobased Antimicrobial Pickering Emulsions

We present the development of surfactant-free, silica-free and fully biobased oil-in-water antimicrobial Pickering emulsions, based on the self-assembly of β-cyclodextrin and phytoantimicrobial oils (terpinen-4-ol or carvacrol). Undecylenic acid (UA), derived from castor oil, can be used as bio-based drug to treat fungal infection, but is less effective than petroleum-based drugs as azole derivatives. To maximize its antifungal potential, we have incorporated UA in fully biobased Pickering emulsions. These emulsions are effective against fungi, Gram-positive and Gram-negative bacteria. The carvacrol emulsion charged with UA is +390 % and +165 % more potent against methicillin-resistant S. aureus (MRSA), compared to UA and azole-based commercial formulations. Moreover, this emulsion is up to +480 % more efficient that UA ointment against C. albicans. Finally, remarkable eradication of E. coli and MRSA biofilms was obtained with this environmental-friendly emulsion.

Natural biflavonoids as potential therapeutic agents against microbial diseases

Microbes broadly constitute several organisms like viruses, protozoa, bacteria, and fungi present in our biosphere. Fast-paced environmental changes have influenced contact of human populations with newly identified microbes resulting in diseases that can spread quickly. These microbes can cause infections like HIV, SARS-CoV2, malaria, nosocomial Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA), or Candida infection for which there are no available vaccines/drugs or are less efficient to prevent or treat these infections. In the pursuit to find potential safe agents for therapy of microbial infections, natural biflavonoids like amentoflavone, tetrahydroamentoflavone, ginkgetin, bilobetin, morelloflavone, agathisflavone, hinokiflavone, Garcinia biflavones 1 (GB1), Garcinia biflavones 2 (GB2), robustaflavone, strychnobiflavone, ochnaflavone, dulcisbiflavonoid C, tetramethoxy-6,6″-bigenkwanin and other derivatives isolated from several species of plants can provide effective starting points and become a source of future drugs. These biflavonoids show activity against influenza, severe acute respiratory syndrome (SARS), dengue, HIV-AIDS, coxsackieviral, hepatitis, HSV, Epstein-Barr virus (EBV), protozoal (Leishmaniasis, Malaria) infections, bacterial and fungal infections. Some of the biflavonoids can provide antiviral and protozoal activity by inhibition of neuraminidase, chymotrypsin-like protease, DV-NS5 RNA dependant RNA polymerase, reverse transcriptase (RT), fatty acid synthase, DNA polymerase, UL54 gene expression, Epstein-Barr virus early antigen activation, recombinant cysteine protease type 2.8 (r-CPB2.8), Plasmodium falciparum enoyl-acyl carrier protein (ACP) reductase or cause depolarization of parasitic mitochondrial membranes. They may also provide anti-inflammatory therapeutic activity against the infection-induced cytokine storm. Considering the varied bioactivity of these biflavonoids against these organisms, their structure-activity relationships are derived and wherever possible compared with monoflavones. Overall, this review aims to highlight these natural biflavonoids and briefly discuss their sources, reported mechanism of action, pharmacological uses, and comment on resistance mechanism, flavopiridol repurposing and the bioavailability aspects to provide a starting point for anti-microbial research in this area.

History of cyclodextrin-based polymers in food and pharmacy: a review

Cyclodextrins are glucose macrocycles whose inclusional capabilities towards non-polar solutes can be modulated with the help of other macrostructures. The incorporation of cyclodextrin moieties into larger structures produces five types of new materials: crosslinked networks, functionalized chains, amphiphilic cyclodextrins, polyrotaxanes and nanocomposites. This review presents crosslinking and grafting to prepare covalently-attached cyclodextrins, and applications in the food and pharmaceutical sectors, from an historical point of view. In food science, applications include debittering of juices, retention of aromas and release of preservatives from packaging. In biomedical science, cyclodextrin polymers are applied classically to drug release, and more recently to gene delivery and regenerative medicine. The remarkable points are: 1) epichlorohydrin and diisocyanates have been extensively used as crosslinkers since the 1960s, but during the last two decades more complex cyclodextrin polymeric structures have been designed. 2) The evolution of cyclodextrin polymers matches that of macromolecular materials with regard to complexity, functionality and capabilities. 3) The use of cyclodextrin polymers as sorbents in the food sector came first, but smart packaging is now an active challenge. Cyclodextrins have also been recently used to design treatments against the coronavirus disease 2019 (COVID-19).

Oral antiseptics against coronavirus: in-vitro and clinical evidence

Angiotensin converting enzyme 2 (ACE2) is the cellular receptor for SARS-CoV-2, so ACE2-expressing cells can act as target cells and are susceptible to infection. ACE2 receptors are highly expressed in the oral cavity, so this may be a potential high-risk route for SARS-CoV-2 infection. Furthermore, the virus can be detected in saliva, even before COVID-19 symptoms appear, with the consequent high risk of virus transmission in asymptomatic/presymptomatic patients. Reducing oral viral load could lead to a lower risk of transmission via salivary droplets or aerosols and therefore contribute to the control of the pandemic. Our aim was to evaluate the available evidence testing the in-vitro and in-vivo effects of oral antiseptics to inactivate or eradicate coronaviruses. The criteria used were those described in the PRISMA declaration for performing systematic reviews. An electronic search was conducted in Medline (via PubMed) and in Web of Sciences, using the MeSH terms: ‘mouthwash’ OR ‘oral rinse’ OR ‘mouth rinse’ OR ‘povidone iodine’ OR ‘hydrogen peroxide’ OR ‘cetylpyridinium chloride’ AND ‘COVID-19’ OR ‘SARS-CoV-2’ OR ‘coronavirus’ OR ‘SARS’ OR ‘MERS’. The initial search strategy identified 619 articles on two electronic databases. Seventeen articles were included assessing the virucidal efficacy of oral antiseptics against coronaviruses. In conclusion, there is sufficient in-vitro evidence to support the use of antiseptics to potentially reduce the viral load of SARS-CoV-2 and other coronaviruses. However, in-vivo evidence for most oral antiseptics is limited. Randomized clinical trials with a control group are needed to demonstrate its clinical efficacy.

Important Roles of Oligo- and Polysaccharides against SARS-CoV-2: Recent Advances

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-initiated outbreak of COVID-19 has spread rapidly around the world, posing a huge threat to public health. Natural oligo- and polysaccharides with low toxicity, good sustainability, high biocompatibility, respectable safety, immune regulation, and antiviral activity can be employed as promising candidates for the prevention and inhibition of viral infections, especially COVID-19. Glycosaminoglycans, marine polysaccharides, terrestrial plant polysaccharides, and some others have exhibited potential antiviral activity against pathogenic viruses, in the format of polysaccharide-centered vaccine adjuvants, nano-based structures, drug conveyance platforms, etc. In this review, significant recent advancements pertaining to the antiviral applications of oligo- and polysaccharides against SARS-CoV-2 are highlighted, including important challenges and future perspectives.

Severe Acute Respiratory Syndrome Coronavirus 2 and Dentistry: A Summative Review of Guidelines issued by National Health Authorities

COVID-19 was first reported in China, in November 2019 and since then the spread of this disease was so rapid that on March 11, 2020, it was declared a pandemic by the World Health Organization. Due to the high transmissibility of the COVID virus and the associated morbidity and mortality, various International and National health authorities released different guidelines for day-to-day living, laying down "new norms" which has impacted our lives enormously. Although these guidelines seem to be convoluted but owing to some differences in the guidelines, it raises an ambiguity in the minds of dentists. Hence, we felt the need of this review to summarize different guidelines issued by various National health authorities for catering emergency and routine dental care. We included guidelines from CDC, ADA, NHS, India, UAE, Egypt, and Tunisia and compared and consolidated to reach a consensus that teledentistry is a good alternative to face-to-face management for nonemergency patients. Triage should be done for all patients coming to the health-care facility. Temperature and other vital parameters should be recorded in our daily practice. Antibacterial mouth rinses before the dental procedure can reduce the microbial load and therefore can alleviate transmission. To reduce indirect transmission through fomites on inanimate objects various waiting area changes must be ensured. Air conditioners can be used in well-serviced conditions with due care given to ventilation of the operatory after each patient. Strict disinfection protocols and personal protective equipment for dentist safety are mandatory.

Dental workers in front-line of COVID-19: an in silico evaluation targeting their prevention

OBJECTIVE

SARS-CoV-2 has high human-human transmission rate. The aerosols and saliva droplets are the main contamination source. Thus, it is crucial to point out that dental practitioners become a high-risk group of contagion by SARS-CoV-2. Based on this, protocols have been recommended to avoid cross-contamination during dental care; however, appropriate evidence has not yet been established. Our study sought to make a screening, by in silico analysis, of the potential of mouth rinses used in dental practices to prevent the dental workers' contamination by SARS-CoV-2.

METHODOLOGY

Multiple sequence comparisons and construction of the phylogenetic tree were conducted using the FASTA code. Therefore, molecular docking investigation between SARS-CoV-2 proteins (Main Protease, Spike Glycoprotein, Non-structure Protein, and Papain-like Protease) and molecules used in dental practices (chlorhexidine digluconate, hydrogen peroxide, cetylpyridinium chloride, povidone-iodine, gallic acid, β-cyclodextrin, catechin, and quercetin) was performed using AutoDock Vina. Moreover, 2D interactions of the complex protein-ligand structure were analyzed by Ligplot+.

RESULTS

The obtained results showed a remarkable affinity between SARS-CoV-2 proteins and all tested compounds. The chlorhexidine digluconate, catechin, and quercetin presented a higher affinity with SARS-CoV-2.

CONCLUSIONS

The overall results allowed us to suggest that chlorhexidine is the most suitable active compound in reducing the SARS-CoV-2 salivary load due to its better binding energy. However, in vivo studies should be conducted to confirm their clinical use.