To the Editor,Is it worth wearing a face mask? That is the question many people ask during the COVID-19 pandemic. To better understand answers of individuals to this question and their subsequent risk, we first recall the prisoner’s dilemma, a classic example of Game Theory, and then apply the same ideas to the decision of wearing a face mask.In the prisoner’s dilemma, two individuals, A and B, are arrested and put in a solitary confinement being both suspected of a robbery.1 Each of the prisoners has a choice between either testifying that the other committed the crime, or remaining silent. The prosecutor comes with the following offer to each prisoner separately: if you testify and the other remains silent, you will be free and the other will be imprisoned for three years, and vice versa. However, if you both testify, you will both get two years of imprisonment. Finally, if you both remain silent, you get one year each. At the personal level, testifying that the other did it is more interesting than remaining silent: if the other prisoner remains silent, testifying will get you free; if he testifies, testifying will result in two years in prison instead of three. Therefore, the two prisoners will tend to testify against each other and will get two years of imprisonment each. Meanwhile, if they had both cooperated and remained silent, they would both have ended up in a better situation as they would have been sentenced to one year of imprisonment instead of two.Consider now a group of N +1 individuals among whom contact patterns and disease transmission are the same in a situation where there is sustained human-to-human infection. Here, we are looking at the consequences of getting infected (P) if an individual i decides to wear a mask or not, and the effort (E) needed to get and wear the mask. Let C0 be the risk of i getting infected when all other N individuals wear a mask, and δ1, δ2, …, δN , the additional risk of getting infected when 1, 2, …, N subjects don’t wear a mask. Denote the percentage of protection obtained when wearing a mask by ε. The probability of i being infected and the effort needed when deciding to wear a mask or not, can be formulated as shown in Table 1.When, for example, r individuals do not wear a mask, if idecides to wear a mask, the effort f needed for this decision results in a decreased risk of infection is (C0+δ r)ε . Weighing this gain against the effort helps in choosing whether to wear a mask or not.At the individual level, i may well be tempted not to wear a mask: for non-surgical masks the gain (C0+δ r)ε can be low, as the level of protection can be small against submicron particles.2 In addition, if improperly manipulated, masks may even increase the risk of contamination.3 Finally, COVID-19 infection was reported to also happen via the eyes which are not covered by the mask.4 All this while a substantial effortf may be needed to be able to manage the discomfort and proper handling of the mask.However, if all the other individuals, reasoning like i , also decide not to wear masks the resulting risk of getting infected becomes C0 + δN . This would mean an increase of C0 ε + δN in infection risk compared to the situation where everyone wore a mask. The addition of δN to the reduction in infection risk can justify wearing a mask as δN is likely to be nonnegligible: if everybody, including the infected ones who are asymptomatic, but infectious, were wearing a mask, this could significantly reduce the virus transmission.5,6,7 In fact, the indirect protective effect of everybody else wearing a mask on decreasing the infection risk δN may be much higher than the direct protective effect (C0+δ r)ε of wearing a mask.Other factors may influence the decision of whether to wear or not a mask, but it is unlikely that the protective aspects and the burden linked to their use would not play significant roles in the decision of wearing them. Given a potentially weak protective effect, a significant effort needed to wear them, and a marked disease containment indirect effect, we may well end up in a prisoner’s dilemma situation. The question is then how to bring the individuals to cooperate and reach the optimal situation of wearing masks. Several options can be considered, spanning from simple encouragement to enforcement. Educating the public by explaining the benefit of everybody wearing even imperfectly sealed masks could provide a potentially cheap and effective measure.8Another option could be to lower the effort f by making good quality and easy to use masks widely available. These initiatives along with other incentives to foster a cooperative behaviour amongst individuals could be key to achieve widespread use of masks to fight against the COVID-19 pandemic, especially when easing lockdown restrictions.DisclaimerEmmanuel Aris is currently employed by GSK, but wrote this article in his personal capacity. The views expressed are his own and do not necessarily represent the views of GSK.References1. Nash J. Non Cooperative Games. Annals of Mathematics 1951;54: 286–295. DOI: 10.2307/1969529.2. Rengasamy S, Eimer B, Shaffer RE. Simple Respiratory Protection—Evaluation of the Filtration Performance of Cloth Masks and Common Fabric Materials Against 20–1000 nm Size Particles. Ann. Occup. Hyg. 2010; 54:789–798. DOI: 10.1093/annhyg/meq044. Epub 2010 Jun 28.3. World Health Organization. Advice on the use of masks in the community setting in Influenza A (H1N1) outbreaks. Interim guidance (3 May 2009). http://www.who.int/csr/resources/publications/Adviceusemaskscommunityrevised.pdf Date: 2020. Accessed April 20th 2020.4. Li JPO, Lam DSC, Chen Y, et al . Novel Coronavirus disease 2019 (COVID-19): The importance of recognising possible early ocular manifestation and using protective eyewear. Br J Ophthalmol 2020;104: 297-298. DOI:10.1136/bjophthalmol-2020-315994.5. Yu X, Yang R. COVID-19 transmission through asymptomatic carriers is a challenge to containment. Influenza Other Respi Viruses . 2020;00:1–2.6. Feng S, Shen C, Xia, N, et al . Rational use of face masks in the COVID-19 pandemic. Lancet Respir Med 2020 https://doi.org/10.1016/ S2213-2600(20)30134-X.7. Johnson DF, Druce JD, Birch C, Grayson ML. A Quantitative Assessment of the Efficacy of Surgical and N95 Masks to Filter Influenza Virus in Patients with Acute Influenza Infection. Clinical Infectious Diseases 2009; 49: 275–277 DOI: 10.1086/600041.8. Greenhalgh T, Schmid, MB, Czypionka T, et al. Face masks for the public during the covid-19 crisis. BMJ , 2020;369:m1435 DOI: https://doi.org/10.1136/bmj.m1435.
The present study reports nonlinear optical properties such as first and second hyper polarizabilities (β and γ) of Y-shaped polymer (P1) and substituted polymers. The basic Y-shaped polymer (R=R1=H) named as P1. Upon substitution of one OCH3 group in ortho position of Oxygen becomes polymer P2 (R1=H, R=OCH3) and two OCH3 group as P3 (R1=R=OCH3). We have also reported structural parameters, vibrational and electronic absorption spectra of polymer and substituted using quantum chemical methods. The geometrical parameters such as dipole moment, bond length and angles are reported at B3LYP/6-311++g** level of theory. In addition, the vibrational, electronic absorption spectra and NLO properties are also reported at the same level of theory. There is significant change in dipole moment and energy observed whereas symmetry, bond length and angles are resembling in Y-shaped and substituted polymer. The vibrational spectra of Y-shaped polymer (P1) having the intense peak is C-H stretching mode observed at 1258 cm-1. These Theoretical vibrational modes are well matching with available experimental determinations. The method dependent and the along the X, Y and Z-direction hyperpolarizabilites also reported. This study confirms the polymer P1 and P2 showing first and second hyperpolarizability response whereas P3 do not show. The electronic absorption spectra for polymer and substituted polymers are also reported at the same level of theory using (TDDFT) approach. The wavelength of electronic transition, oscillator strength and HOMO-LUMO gap also reported.
The novel coronavirus outbreak arose in Wuhan, China in Dec, 2019. It is declared the 6th public health emergency by the WHO and named as COVID-19. SARS-CoV-2 is non-segmented positive sense ssRNA virus, belongs to the Coronaviridae under the Nidovirales and spread largely in human being and other mammals. Person to person, airborne and surface transmission is common, the virus get entered to host through nose, mouth, eyes, food, water and feces. An infected patients can transmit the virus to 2.2 healthy individuals. A patient in the US showed gastrointestinal symptoms vomiting, nausea and pass loose stools. Later the patient declared positive for SARS-CoV-2 on the basis of viral detection in stools and respiratory samples. The gastrointestinal symptoms like diarrhea, nausea, vomiting, abdominal discomfort and detection of SARS-CoV-2 in stools of infected and recovered patients indicates potential oral-fecal transmission route, it could be potential risk for the spread of COVID-19. The flatus is gas produced by aerophagia or bacterial fermentation in intestine and expelled out through esophagus or anus. It consists of Hydrogen, Oxygen, Nitrogen, Carbon dioxide and Methane, their percentage composition is 99%. Previous study showed that bacteria can transmit through bare-bottom farting. The gastrointestinal manifestation and possible oral-fecal transmission, the flatulence could be the risk of transmission for COVID-19. Personal hygiene must be adapted to prevent the spread of disease.
Introduction: This prospective randomized case-control study was performed to compare the surgical outcomes of our swing-door overlay tympanoplasty with or without absorbable gelatine sponge (AGS, gelfoam) packing in the middle ear cavity, according to the surgical procedure. Subjects and Methods: Fifty-seven patients who underwent swing-door overlay tympanoplasty by a single surgeon were enrolled in the study. The data of 30 patients of the gelfoam-packing group (GPG) and 27 patients of the non-gelfoam-packing group (NGPG) were prospectively collected and compared. Results: Closure of the tympanic membrane was found to be successful in all patients at postoperative 3 months evaluation. NGPG showed a statistically better healing process compared to GPG; earlier epithelialization and less fascia edema in NGPG than in GPG (P<0.05). The air-bone gap (ABG) measured at postoperative 1 and 2 months was smaller in NGPG than GPG, although there were no statistical differences. Conclusion: Swing-door overlay tympanoplasty showed good surgical outcomes in terms of graft uptake rate regardless of AGS packing. However, this study revealed earlier healing process and faster recovery of ABG in NGPG, thereby indicating that the gelfoam in the middle ear may interfere with both hearing recovery and the healing process of neodrum. Non-gelfoam packing in the middle ear cavity appeared to be superior to gelfoam packing in swing-door overlay tympanoplasty.
An 88-year-old lady presented with idiopathic sepsis and ischaemic gangrene of the right breast. Group-A bacteraemia was identified on blood culture. Breast biopsies taken were negative for malignancy. The patient was treated with intravenous antibiotics and fluid resuscitation. Subsequent wound care and continuation of oral antibiotics led to complete recovery.
Electrochemical ammonia synthesis is being actively studied as a low temperature, low pressure alternative to the Haber-Bosch process. This work studied iridium as the electrochemical catalyst, following a previous study of adsorption characteristics on platinum. The characteristics studied include bond energies, bond lengths, spin densities, and free and adsorbed vibrational frequencies for the molecules N2, N, NH, NH2, and NH3. Overall, these descriptive characteristics explore the use of dispersion-corrected Density Functional Theory methods that can model N2 adsorption – the key reactant for electrochemical ammonia synthesis via transition metal catalysis. Specifically, three methods were tested: hybrid B3LYP, a dispersion-corrected form B3LYP-D3, and semi-empirical B97-D3. The latter semi-empirical method was explored to increase the accuracy obtained in vibrational analysis as well as reduce computational time. Two lattice surfaces, (111) and (100), were compared. The adsorption energies are stronger on (100) and follow the trend EB3LYP > EB3LYP-D3 > EB97-D3 on both surfaces.
Avian transgenesis has served as a suitable approach to generate bioreactors for the manufacturing of recombinant proteins. Production in chicken cells comes with significant advantages over other systems including providing the human-like glycosylation on target proteins. In this regard, the oviduct-specific ovalbumin promoter has been one of the ideal candidates to drive the expression of transgenes. Previous plasmid-based studies on the regulatory sequences of ovalbumin promoter have led researchers to exploit ovalbumin regulatory elements out of their native genomic context (ex situ) to direct transgene expression in the transgenic chicken bioreactors. Although the inherent limitations on the ex situ use of ovalbumin promoter have promoted the use of native ovalbumin promoter for the expression of a transgene, generation of transgenic chicken is relatively difficult, inefficient, and time-consuming. To overcome these obstacles, in this study we show that CRISPR-mediated deletion of some distal ovalbumin promoter sequences in a non-oviduct cell can lead to the significant expression of the ovalbumin gene, and also a knocked-in reporter, in an estrogen-independent manner. These findings overcome the limitation of cloned promoters, where the promoter regulatory sequences have to be taken out of their cis context and also their native spatial nuclear organization into a plasmid.
SARS-CoV-2 has claimed more than 300,000 lives while infecting 4 million individuals worldwide. There are no specific treatments for COVID-19. Symptoms vary from very mild/asymptomatic to severe, including admission to ICU. Strong sex-bias in COVID-19 have been noted with males showing more than double the odds of requiring ICU admission and higher mortality. Reproductive steroids, including estrogens, progesterone and its physiologically-active metabolite, allopregnanolone exert anti-inflammatory actions and influence the immune system. Intriguingly, pregnant women with COVID-19 appear to experience milder symptoms. In some pregnant women escalated symptoms severity is observed immediately postpartum in coincidence with the rapid hormonal drop associated with parturition. This finding suggests that reproductive steroids’ anti-inflammatory effects and their role in reshaping competence of immune cells may protect during pregnancy. The hypothesis that estradiol, progesterone may provide a treatment against COVID-19 in men and in postmenopausal women is discussed.
The synthesis of starch-based physical hydrogels in combination with chitosan and polyvinyl alcohol, and their potential co-application with chitosan nanoparticles was evaluated. The potential of starch-chitosan hydrogel obtained by physical/chemical method for tissue engineering uses was also studied in a mouse wound healing model. Although the microscopical structure of each synthesized hydrogel suggests a possible biological application, starch-polyvinyl alcohol hydrogel exhibited rigid behavior with minor channel diameters, a lower swelling rate (less than 300%), and negatively affected cell viability in a cytotoxicity assay. Starch-chitosan hydrogel obtained by chemical crosslinking with glutaraldehyde demonstrated the higher swelling rate (about 1100%), cell viability values over 80%, and a homogeneous tri-dimensional structure; along with an excellent interaction with chitosan nanoparticles. This type of hydrogel was selected for an in vivo experiment, showing significant differences in wound healing process against a non-treated control, in terms of inflammation, exudate production and tissue recovering.
The global pandemic from Sars-cov-2 has down caused thousands of deaths worldwide, triggering a health crisis in the various countries involved, with few precedents in history. To date there are no vaccines for prophylaxis, and there are no antivirals directed against the virus. Among the therapeutic options that have shown effectiveness is passive immunization with immune plasma from convalescent patients cured of the infection. Plasma collected from patients cured of Sars-cov-2 infection is rich in antibodies that neutralized the pathogen. Plasma therapy has already demonstrated its efficacy in other epidemics, such as Sars-Cov and MERS. To date, there are limited data for its use in sars-Cov-2 infection, both for prophylaxis and treatment, but the few existing data bode well for the scientific world. Many questions are still unresolved, when to administer it? At what dosage? When is it most appropriate to take the plasma from the cured patient? Are there different answers depending on gender and age? Certainly in view of the high number of patients infected and cured by Sars-Cov-2, there could be a high amount of plasma from donor patients. In this article we want to give an overview on a current and important topic in the perspective of the battle against the new Sars-Cov-2, analysing the therapeutic successes in past epidemics, the clinical data currently available, the future prospect and an expert opinion.
The role of CD4+ Treg in immune responses has been well established. More recently a role of CD8+ Treg in the regulation of immune responses in health and autoimmune diseases has been investigated. Furthermore, different investigators have used different markers to define CD8 Treg. Finally, regulatory effects of CD8 Treg have been studied against T cell responses; however, their role in regulating B cell proliferation and immunoglobulin production has not been evaluated. Therefore, in this study we examined the effect of two types of CD8 Treg on B cell proliferation and immunoglobulin production. Methods: Purified CD8+ T cells were activated with anti-CD3/CD28 for 48 hours and then sorted into two different types of CD8 Treg as defined by two different sets of markers, CD8+CD183+CCR7+CD45RA-, and CD8+CD183+CD25highCD278+. Purified B cells were co-cultured with sorted CD8 Treg at 1:1, 1:1/2, 1:1/4 ratios, and activated with anti-CD40 and CpG. B cell proliferation was assessed by CFSE dye dilution assay and immunoglobulin production by ELISA assay. Results: Our data show CD183+CCR7+CD45RA- CD8 T reg significantly inhibited B cell proliferation and inhibited IgM and IgG production but not of IgA production at 1:1 ratio only. However, CD183+CD25highCD278+ CD8 Treg inhibited significantly B cell proliferation at 1:1 and 1:1/2 ratio and IgM, IgG, and IgA production at all ratios. In Conclusion, CD8 Treg regulate B cell responses, and CD183+CD25highCD278+ CD8 Treg are more powerful regulators of B cell proliferation and Immunoglobulin production than CD183+CCR7+CD45RA- CD8 Treg.
The current study investigates the correlation between biological activity and physicochemical properties of a few specific estradiol isomers. Theoretical studies on the physicochemical properties of estradiol isomers were performed using different quantum mechanical methods. The computational methods used in this study include the Density Functional Theory (DFT) method, the Hartree-Fock (HF) method and Semi-empirical (AM1) method. Some physicochemical properties such as dipole moment, molecular weight, the energy of the highest occupied molecular orbital (E HOMO), the energy of the lowest unoccupied molecular orbital (E LUMO), polarizability, the octanol-water partition coefficient (Log P), polar surface area (PSA) the number of hydrogen bond donors (HBDs) and the number of hydrogen bond acceptors (HBAs), the surface area, volume of the molecule, and ovality are calculated for the isomers. However, only dipole moment values are suitable to identify a correlation of experimental biological activity of estradiol isomers. To the best of our knowledge, this is the first report on the relationships between dipole moment and biological activities of estradiol isomers. It is observed that the active compound has a significantly higher dipole moment value compared to the inactive compound. We have also analyzed the geometrical and graphical models of these isomers and related compounds to evaluate the differences in the molecular charge distributions.
Rationale, aims, and objectives: Post-hospitalization follow-up within 30 days following discharge has been shown to positively impact time to readmission, healthcare costs, and patient self-reported adherence and satisfaction. We aimed to improve resident satisfaction with the process of establishing post-hospitalization, primary care provider (PCP) follow-up. Methods: In this quality improvement study we surveyed all internal medicine residents at our institution regarding their satisfaction with the process of establishing PCP follow-up at the time of hospital discharge. A streamlined process was developed and two subsequent interventions were enacted; a dedicated teaching session and distribution of pocket cards outlining the process. Residents were then surveyed following each intervention to assess for impact on overall satisfaction and burden of work. Results: Initially, 77.3% of residents were not satisfied with the process of establishing post-hospitalization PCP follow-up. Following the first intervention there was a trend towards increasing satisfaction rates by 16.7% (p= 0.20), and after the second intervention there was a statistically significant increase in satisfaction rates from baseline by 44% (p= 0.007). There was also a reduction in the feeling of workload burden associated with establishing PCP follow-up from 32% to 25%, and over 67% of participants either agreed or strongly agreed that the workload was not too burdensome. Conclusion: This quality improvement initiative established that resident physicians at our institution previously found the process of establishing PCP follow-up at the time of patient discharge both confusing and burdensome. Through the implementation of our interventions we were able to achieve our aims of improving resident satisfaction.
Seed predators have the potential to act as agents of natural selection that influence seed traits. Accordingly, plants deploy a variety of mechanisms (e.g. resistance and tolerance strategy) to lessen the impact of predation on seed crop or on an individual seed. In this study, we found a novel mechanism (i.e. cloning strategy) in a tropical plant species in countering animal predation. We found both rodent damaged and human artificially damaged seed fragments of a large-seeded tree Garcinia xanthochymus in the Xishuangbanna tropical forest of China could develop into seedlings in both field and laboratory conditions. G. xanthochymus seed has no endosperm in seeds, and its seed tissue own strong capacity of differentiation and cloning. Seed damage would negatively affect seedling growth and germination, but the seed germination rate was remarkably high. Our study suggests that, as a novel strategy countering animal predation, seed cloning would play a significant role in stabilizing the mutualism between plant and animals.
Synchronous brain tumors are rare in children. We present 2 unique cases of synchronous brain tumors and we elaborate on their presentation, diagnosis, approach to management, and outcome. The first case describes a unique and previously unreported combination of a supratentorial anaplastic ependymoma and a cerebellar low-grade glioma.
Stem cell (SC) differentiation towards somatic cells has proven to be an effective technique in the understanding and progression of regenerative medicine. Despite improvements, concerns regarding the efficiency of differentiation and the differences between SC products and their in vivo counterparts must be addressed. Biomaterials that mimic endogenous growth conditions represent one recent method used to improve the quality and efficiency of SC differentiation. Here, we aim to use bioinformatics approaches to accomplish two aims: 1) determine the effect of different biomaterials on SC growth and differentiation, and 2) understand the effect of cell of origin on the differentiation potential of multipotent SCs. First, we demonstrate that the dimensionality (2D versus 3D) and the degradability of biomaterials affects the way that the cells are able to grow and differentiate at the transcriptional level. Additionally, the particular cell of origin is an important factor in determining the response of SCs to same biomaterial transcriptionally. Our data demonstrates the ability of bioinformatics to understand novel molecular mechanisms and context by which SCs are most efficiently able to differentiate. These results and strategies may suggest proper combinations of biomaterials and SCs to achieve high differentiation efficiency and functionality of desired cell types.
Atomically precise metallic clusters behaving as superatoms, are relevant building blocks towards new materials under the bottom-up approach. Here we discussed the plausible formation of the Cu10Ru cluster as a superatomic specie accounted its 1S2 1P6 1D10 shell order, with the aim of identification of particular clusters with enhanced stability. By stochastic structure search on Cu10Ru clusters, we found six low-lying cluster isomers with ΔE values from 0.0 to 4.7 kcal∙mol above the ground state denoting an endohedral motif with the Ru dopant inside the Cu10 cage, as the favored structures. By using molecular dynamics simulations we found a clear trend of encapsulation of the Ru atom at low temperatures, quantified by the Cu-Ru bonding distances during the annealing procedure. The 17-ve counterpart, Cu9Ru shows a large electron affinity, owing to the trend to achieve a electronic shell closing as a new superhalogen species. These results are useful for further rationalization and design of novel superatoms expanding the libraries of endohedral clusters.
Background. Differential diagnosis of Low-back pain (LBP) is complex and a prominent health care issue at all Health-care levels; guidance may come from patients’ history cues and clinical examination signs. Human and animal studies report that lumbar radicular pain (LRP) may be diagnosed, at all care settings, by the evaluation of subjective responses of injured lumbar nerves to a strain applied at the buttock. The Buttock Applied Strain (BUAS-test) may guide the differential diagnosis of LBP. Following an ex-adiuvantibus criterion, clinical improvement of LRP, diagnosed with the BUAS-test and congruently treated, may support this test diagnostic ability. Methods. Among 258 LRP patients, positive at V1, to the BUAS-test (with/without positive Straight-Leg-Raising-Test, SLRT), the effect of gabapentin on painDETECT (PD) questionnaire and BPI outcomes was quantified in the follow-up visit (V2). We hypothesized that, at V2, >50% of the sample would present negative PD-outcome, significant (t-Test), and 2 points V2-V1 differences for each the BPI-item’s score. Multinomial-Logistic-Regression (MLR) and χ2 analyses were used to evaluate the PD-V2-outcomes’ dependence upon independent variables. Results. Of the sample, 77% reported Negative PD-V2-outcome. V2-V1 differences of all BPI-items were significant and >2 points. PD-V2-outcomes showed significant associations with SLRT-V1 and PD-V1, respectively, but not with gender, age group, or pain-site. MLR showed a significant relationship between SLRT-V1 and PD-V2 outcomes. Conclusions. Among LRP patients, diagnosed by the BUAS-test and treated with gabapentin, all prespecified endpoints were reached. These results may be considered a piece of ex-adiuvantibus evidence for the BUAS-test ability to diagnose LRP. While positive BUAS-test implies potential LRP, the co-presence with positive SLRT may imply a severer LRP condition. Further prospective research, in different settings and direct clinical measures, is needed.