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Complication rates for paediatric tonsillectomy based on Scottish national data 2000-...
Christy Moen
Laura Downie

Christy Moen

and 2 more

March 02, 2022
It is important to give parents accurate information about complication rates as part of the process of informed consent for surgery.  National, routinely-collected data give an opportunity to estimate the rates of rare adverse events such as bleeding, blood transfusion and death.We reviewed data for all Scottish NHS hospitals over the time period 2000-2018 to identify all children (aged 0-16 years) undergoing tonsillectomy, and to identify adverse events occurring within 30 days of the procedure.Readmission to hospital was required in 2%.Surgical arrest of haemorrhage was required in 1%.Blood transfusion occurred in 0.1% and death occurred in one child out of 50,194.
Obstetric anal sphincter injury by maternal origin and length of residence: a letter
Rinchen Zangmo
Avir Sarkar

Rinchen Zangmo

and 3 more

November 16, 2021
Obstetric anal sphincter injury by maternal origin and length of residence: a letterIt gives us great pleasure to read the study entitled “Obstetric anal sphincter injury (OASI) by maternal origin and length of residence: a nation-wide cohort study” by Sorbye and Bains et al1. We appreciate the authors for conducting a large scale multicentric cohort study on this newer aspect of OASI. However, we wish to make certain observations to further help in comprehending the results.Firstly, the eligibility criteria for the recruitment of participants needs clarification as to why foreign-born women with Norwegian-born parents were excluded from enrolment. Keeping them as a separate group could have been beneficial in assessing whether environmental factors due to migrating out of Norway had an impact on the incidence of OASI. Futhermore, the greater odds of OASI among women with foreign-born partners has to be digested with a pinch of salt. A subgroup analysis comparing the newborn birth weight (NBW) and head circumference (HC) could be instrumental in solving this dilemma. Prior studies by Vik et al from Norway had demonstrated similar outcomes in neonatal survival as well2. In the absence of significant difference in NBW and HC, social issues need due consideration. It probably opens up the arena for potential future research in this very field.The study does mention that the mean HC of newborns to foreign-born women with OASI did not differ from Norwegian-born counterparts without OASI. But the p value mentioned alongside in the text is 0.000, which would amount to high significance. This area needs clarification.Table 3 has stratified the association between OASI and the length of residence in Norway. We appreciate this robust comparison as this outcome was vital in hypothesizing the impact of environment and lifestyles on the incidence of OASI. But, it is quite strange to note that women who had childbirth before their lawful residence (probably had immigrated recently) had lesser odds of OASI compared to those who had legal residence upto 4 years. Discrete analysis of this subgroup of patients might give us a better comprehension. Another analysis which can be done is to assess whether the place of delivery (government or private setup) was significantly affecting the prevalence of OASI. It can be thought of as an auxiliary outcome. This will ultimately help in addressing the barriers to optimal utilization of resources and will probably stimulate the health care policy to achieve equitable care across the nation.References:Sorbye IK, Bains S, Vangen S, Sundby J, Lindskog B, Owe KM. Obstetric anal sphincter injury by maternal origin and length of residence: a nation-wide cohort study. BJOG. 2021 Oct 28. doi: 10.1111/1471-0528.16985. Epub ahead of print. PMID: 34710268.Vik ES, Aasheim V, Nilsen RM, Small R, Moster D, Schytt E. Paternal country of origin and adverse neonatal outcomes in births to foreign-born women in Norway: A population-based cohort study. PLoS Med. 2020 Nov;17(11):e1003395.
A common low back pain hiding tuberculous sacro-iliitis .
saoussen miladi
Ben Ayed Hiba

saoussen miladi

and 9 more

November 16, 2021
The sacroiliac joint is rarely affected by tuberculosis. Only few cases have been reported. Consequently, the diagnosis is often delayed. This case report highlights the importance of continued awareness for early detection and treatment of a tuberculous sacroiliac joint infection.
How Covid-19 spreads: narratives, counter-narratives and social dramas
Trisha Greenhalgh

Trisha Greenhalgh

and 2 more

November 16, 2021
This paper offers a critique of UK government policy based on mode of transmission of SARS-CoV-2 (which in turn followed misleading advice from the World Health Organisation) through the lens of policymaking as narrative. Two flawed narratives—“Covid is droplet- not airborne-spread” and “Covid is situationally airborne” (that is, airborne transmission is unusual but may occur during aerosol-generating medical procedures and severe indoor crowding)—quickly became dominant despite no evidence to support them. Two important counter-narratives—“Covid is unequivocally airborne” and “Everyone generates aerosols; everyone is vulnerable”— were sidelined despite strong evidence to support them. Tragic consequences of the flawed policy narrative unfolded as social dramas. For example, droplet precautions became ritualised; care home residents died in their thousands; public masking became a libertarian lightning rod; and healthcare settings became occupational health battlegrounds. In a discussion, we call for bold action to ensure that the science of SARS-CoV-2 transmission is freed from the shackles of historical errors, scientific vested interests, ideological manipulation and policy satisficing.
Comparison of materials for rapid passive collection of environmental DNA
Cindy Bessey
Yuan Gao

Cindy Bessey

and 5 more

November 16, 2021
Passive collection is an emerging sampling method for environmental DNA (eDNA) in aquatic systems. Passive eDNA collection is inexpensive, efficient, and requires minimal equipment, making it suited to high density sampling and remote deployment. Here, we compare the effectiveness of nine membrane materials for passively collecting fish eDNA from a 3 million litre marine mesocosm. We submerged materials (cellulose, cellulose with 1% and 3% chitosan, cellulose overlayed with electrospun nanofibers and 1% chitosan, cotton fibres, hemp fibres and sponge with either zeolite or active carbon) for intervals between five and 1080 minutes. We show that for most materials, with as little as five minutes submersion, mitochondrial fish eDNA measured with qPCR, and fish species richness measured with metabarcoding, was comparable to that collected by conventional filtering. Furthermore, PCR template DNA concentrations and species richness were generally not improved significantly by longer submersion. Species richness detected for all materials ranged between 11 to 37 species, with a median of 27, which was comparable to the range for filtered eDNA (19-32). Using scanning electron microscopy, we visualised biological matter adhered to the surface of materials, rather than entrapped, with images also revealing a diversity in size and structure of putative eDNA particles. Environmental DNA can be collected rapidly from seawater with a passive approach and using a variety of materials. This will suit cost and time-sensitive biological surveys, and where access to equipment is limited.
An unexpected difficult airway due to an undiagnosed congenital lingual thyroglossal...
Yoshiki Kohashi
Tomohiro Yamamoto

Yoshiki Kohashi

and 3 more

November 16, 2021
Lingual thyroglossal duct cysts can be a rare cause of feeding difficulties in infants. Here, we describe a case of an undiagnosed lingual thyroglossal duct cyst in an infant with vomiting and feeding difficulty, who underwent surgery for Hirschsprung's disease and had an unexpected difficult airway during anesthesia induction.
Therapeutic Effect of His-Purkinje System Pacing Proportion on Persistent Atrial Fibr...
Fei Tong
Zhijun Sun

Fei Tong

and 1 more

November 16, 2021
Background His-Purkinje system pacing(HPSP) combined with atrioventricular node (AVN) ablation is an effective therapy for atrial fibrillation (AF) patients with heart failure (HF).However, AVN ablation is accompanied with some limitations and disadvantages. HPSP combined with β -blocker reduces inherent heart rate and increases pacing ratio, which may be an alternative to HPSP combined with AVN ablation. This study was to assess the therapeutic effect of different His-Purkinje system pacing proportions on AF patients with HF. Methods The study enrolled 30 consecutive persistent AF patients with HF who underwent HPSP. Heart rate was controlled by medical therapy. New York Heart Association (NYHA) classification, serum NT-proBNP concentration, echocardiographic parameters were assessed at each follow-up. Results The best cut-off value of pacing proportion to predict MACE by ROC analysis was 71%. In high pacing proportion group, there were significant improvements of NYHA classification, NT-proBNP concentration, LVEF and LVEDD from the baseline in wide QRS complex patients and HFrEF patients, and there were significant improvements in NYHA classification, NT-proBNP concentration from baseline in narrow QRS complex patients and HFpEF patients, moderate but no significant improvements of LVEF and LVEDD were observed in those patients groups. In low pacing proportion group, there were no significant improvements of NT-proBNP concentration, LVEDD or LVEF regardless of baseline QRS duration or LVEF (P > 0.05). Conclusion High pacing proportion of HPSP has a beneficial effect on the prognosis of persistent AF patients with heart failure.
The National Burden of Influenza-Like Illness and Severe Respiratory Illness Overall...
Stefano Tempia
Jocelyn Moyes

Stefano Tempia

and 11 more

November 16, 2021
Background Estimates of the disease burden associated with different respiratory viruses are severely limited in low- and middle-income countries, especially in Africa. Methods We estimated age-specific numbers and rates of medically and non-medically attended influenza-like illness (ILI) and severe respiratory illness (SRI) that were associated with influenza, respiratory syncytial virus (RSV), rhinovirus, human metapneumovirus, adenovirus, enterovirus and parainfluenza virus types 1-3 after adjusting for the attributable fraction (AF) of virus detection to illness in South Africa during 2013-2015. Rates were reported per 100,000 population. Results The mean annual rates were 51,383 and 4,196 for ILI and SRI, respectively. Of these, 26% (for ILI) and 46% (for SRI) were medically attended. Among outpatients with ILI, rhinovirus had the highest AF-adjusted rate (7,221), followed by influenza (6,443) and adenovirus (1,364); whereas, among inpatients with SRI, rhinovirus had the highest AF-adjusted rate (400), followed by RSV (247) and influenza (130). Rhinovirus (9,424) and RSV (2,026) had the highest AF-adjusted rates among children aged <5 years with ILI or SRI, respectively; whereas rhinovirus (757) and influenza (306) had the highest AF-adjusted rates among individuals aged ≥65 years with ILI or SRI, respectively Conclusions There was a substantial burden of ILI and SRI in South Africa during 2013-2015. Rhinovirus and influenza had a prominent disease burden among patients with ILI. Rhinovirus had the highest burden of illness among patients of any age with SRI, followed by RSV. RSV and influenza were the most prominent causes of SRI in children and the elderly, respectively.
Turnover of sex defining mutation provides an insight into evolution of sex chromosom...
Liang Guo
Danilo  Malara

Liang Guo

and 3 more

November 16, 2021
A document by Liang Guo. Click on the document to view its contents.
The effect of hormone replacement therapy on the survival of UK women: a retrospectiv...
Nurunnahar Akter

Nurunnahar Akter

November 16, 2021
Nurunnahar Akter,a Elena Kulinskaya,a Nicholas Steel,b Ilyas Bakbergenulya a School of Computing Sciences, University of East Anglia, Norwich, UKb Norwich Medical School, University of East Anglia, Norwich, UKCorrespondence: Nurunnahar Akter, School of Computing Sciences, University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK. Email: n.akter@uea.ac.ukRunning title: HRT and its impact on all-cause mortality.
Yes, a non‐random distribution, but why do dragonflies and damselflies not follow lat...
Maya Rocha
Freddy Palacino

Maya Rocha

and 3 more

November 16, 2021
1. Latitudinal diversity gradient (LDG) is the increase in species richness towards the equator and is one of the most consistent patterns in biogeography, where current and historical processes contribute to shape the pattern. 2. Despite that LDG patterns have been described for some insects, the underlying mechanisms associated with community assembly and diversification along modern latitudinal diversity gradient pattern remain unknowledge for many groups. 3. Odonata is an old order of insects that originated during the Carboniferous and has diversified through different eras. Here, we defined co-occurrence based on the presence in ecoregions and 1°×1° grid cells of Odonata species in North America NA, to address their species richness, phylogenetic structure, and species diversification rate along the latitudinal gradient. 4. For the whole order, we found the highest species richness at mid-latitudes, while phylogenetic diversity showed a linear positive pattern along the gradient. Our results showed dragonfly assemblages were clustered along all the gradient, suggesting that environmental filtering sorted the assemblages. Whereas damselfly species assemblages were clustered at mid-latitude and overdispersed into both extremes of gradient, probably community assembly is driving by thermal gradients at mid-latitude, by competitive exclusion at south extreme, and by different origins of the biota at the boreal zone. Our results show that apparently most ancestral lineages of Odonata inhabit tropical zones, where diversified and dispersed to the temperate region, although likely also have been diversified into regions of NA, which might be linked with the highest species richness at mid-latitude for both suborders.
Petroleum-contamination drives the shift of microbiome through modifying soil metallo...
Zhe Liu
Meixia Gu

Zhe Liu

and 4 more

November 16, 2021
Soil oil-pollution is one of the most severe environmental issues at present. Shifts of soil metallome and microbiome are essential indicators for risk assessment and remediation of field soil pollutions, but not well studied undergoing the petroleum contamination. In this research, soil samples were collected from a short-term and long-term petroleum-contaminated oil field. The soil physicochemical properties, metallome, microbial community, and polluted and unpolluted soil network were testified. Results showed that the contents of soil total petroleum hydrocarbon, total carbon, total nitrogen, total sulfur, total phosphorus, calcium, copper, manganese, lead, and zinc were increased by petroleum contamination. In contrast, the soil pH was decreased by petroleum contamination regardless of the pollution duration. Petroleum-contamination also reduced bacterial and fungal α-diversity indices. In contrast, bacterial α-diversity was negatively correlated with soil TPH and EC, and fungal α-diversity was negatively correlated with soil EC. Moreover, the relative abundances of Proteobacteria, Ascomycota, Oleibacter, and Fusarium in soil were increased by petroleum contamination. Network analysis showed that number of links, modules and the network invulnerability decreased in PS, followed by the OS group. These results demonstrate that short-term heavy petroleum contamination can cause shifts in soil physicochemical properties, metallome, and microbiome and assemble a less complex and vulnerable soil microbial network. Moreover, natural restoration can hardly amend soil properties and microbial network structure. This research emphasizes that the uncommonly studied soil metallome may play a vital part in the reaction of soil microbial communities to petroleum-contamination and potential application value of synthetic community in bioremediation.
Agricultural practice negatively affects soil microbial diversity and nitrogen functi...
Tiehang Wu
Michael  Sabula

Tiehang Wu

and 4 more

December 06, 2021
Soil microbial diversity and community are determined by anthropogenic activities and environmental conditions, which greatly affect the functioning of ecosystem. We investigated the soil bacterial diversity, communities, and nitrogen (N) functional genes with different disturbance intensity levels from crop, transition, to forest soils at three locations in the coastal region of Georgia, USA. Illumina high-throughput DNA sequencing based on bacterial 16S rRNA genes were performed for bacterial diversity and community analyses. Nitrifying (AOB amoA) and denitrifying (nirK) functional genes were further detected using quantitative PCR (qPCR) and Denaturing Gradient Gel Electrophoresis (DGGE). Soil bacterial community structure determined by Illumina sequences were significantly different between crop and forest soils (p < 0.01), as well as between crop and transition soils (p = 0.01). However, there is no difference between transition and forest soils. Compared to less disturbed forest, agricultural practice significantly decreased soil bacterial richness and Shannon diversity. Soil pH and nitrate contents together contributed highest for the observed different bacterial communities (Correlations = 0.381). Two OTUs (OTU5, OTU8) belonging to Acidobacteriales species decreased in crop soils, however, agricultural practices significantly increased an OTU (OTU4) of Nitrobacteraceae. The relative abundance of AOB amoA gene was significantly higher in crop soils than in forest and transition soils. Distinct grouping of soil denitrifying bacterial nirK communities was observed and agricultural practices significantly decreased the diversity of nirK gene compared to forest soils. Anthropogenic effects through agricultural practices negatively affecting the soil bacterial diversity, community structure, and N functional genes.
Infinitely many homoclinic solutions for double phase problem on integers
Robert Steglinski

Robert Steglinski

November 16, 2021
We consider a discrete double phase problem on integers with an unbounded potential and reaction term, which does not satisfy the Ambrosetti--Rabinowitz condition. A new functional setting was provided for this problem. Using the Fountain and Dual Fountain Theorem with Cerami condition, we obtain some existence of infinitely many solutions. Our results extend some recent findings expressed in the literature.
Prevalence and predictors of bradyarrhythmias requiring Permanent Pacing in patients...
luigi tassetti
Carlo Fumagalli

luigi tassetti

and 8 more

November 16, 2021
Introduction: Bradyarrhythmias are an established red flag for storage cardiac conditions including Anderson-Fabry disease (AFD). The prevalence of bradyarrhythmias requiring a pacemaker (PM) and their timing in AFD is unresolved. We evaluated prevalence and predictors of PM requirement in a large AFD cohort, investigating the occurrence of bradyarrhythmias as initial versus late manifestation. Methods: we retrospectively evaluated 82 consecutive AFD patients referred to our multidisciplinary referral centre from 1994 to 2020 with a median follow up of 6.9 years, identifying those requiring pacing. Univariable analysis was performed to identify cardiac features associated with PM implantantion. Results: Five of 82 (6%) AFD patients required PM implantation (5/39, i.e. 13% of those with cardiac involvement), always in the context of advanced cardiomyopathy. In none, bradyarrhythmias were the presenting feature. Indications included sick sinus syndrome in 3 patients, advanced atrio-ventricular block in 2 patients. QRS prolongation during follow up strongly correlated with the onset of bradyarrhythmias. Conclusions: Severe bradyarrhythmias are relatively frequent in patients with AFD cardiomyopathy, but do not represent a mode of presentation, occurring late in the disease course and always in the context of advanced cardiac involvement. Monitoring QRS variations over time may help to identify patients requiring pacing.
Cytokine concentrations in bronchoalveolar lavage fluid (BALF) from children with sev...
bingru yin
Min Lu

bingru yin

and 5 more

November 16, 2021
Background: It has been well known that overreaction of host immune systems plays a critical role in severe community-acquired pneumonia (SCAP). However, few of previous studies focused on the association between cytokine concentrations in bronchoalveolar lavage fluid (BALF) and SCAP. Object: We examined cytokine concentrations in BALF from children with SCAP and explored predictive value of cytokine concentrations for SCAP. Method: It was a retrospective study. A total of 100 children with SCAP who underwent parallel bronchoalveolar lavage between July 2017 and June 2019 were enrolled. 100 patients with mild community-acquired pneumonia (MCAP) who were admitted to the hospital were matched based on age and sex during the same time period . Basic clinical information were collected. Flow cytometry was used to determine the cytokine concentrations in BALF. Receiver operating characteristic curve was used to analyze their predictive value for SCAP. Result: A total of 106 males and 94 females were included in this study. The results showed that the CRP, PCT, ESR, LDH, and D-dimer were significantly increased in the SCAP group. The SCAP patients also had longer fever duration, hospitalization stays, and higher hospitalization costs. The IL-5,IL-17A,IL-18,and TnF-α in BALF of SCAP group were significantly higher than those in MCAP group. ROC curve analysis demonstrated AUC of those cytokines were all among 0.5~0.7. Conclusion: The IL-5,IL-17A,IL-18,and TnF-α in BALF of children with SCAP group were highe. However, the efficacy of those cytokines in the clinical diagnosis of SCAP is not excellent to be used as a predictor.
Preliminary study on left bundle branch area pacing in children:clinical observation...
Wenlong Dai
baojing guo

Wenlong Dai

and 3 more

November 16, 2021
Objective: To explore the safety and feasibility of left bundle branch area pacing (LBBAP) in children. Methods: This study observed 12 children attempted LBBAP from 2019 to 2021 in our department prospectively. Clinical data, pacing parameters, electrocardiograms, echocardiographic measurements and complications were recorded at implant and during follow-up. Results: The 12 patients aged between 3 and 14ys and weighted from 13 to 48kg. 11 patients were diagnosed with third-degree AVB and 1 patient (case 4) suffered from cardiac dysfunction due to right ventricular apical pacing (RVAP). LBBAP was successfully achieved in all patients with narrow QRS complexes. LVEF of case 4 recovered on the 3rd day after LBBAP. The median of LVEDD Z score of the 12 patients decreased from 1.75 to1.05 3 months after implantation (p<0.05). The median of paced QRS duration was 103ms. The median of pacing threshold, R-wave amplitude and impedance were 0.85V, 15mV and 717Ω respectively and remained stable during follow-up. No complications such as loss of capture, lead dislodgement or septal perforation occurred. Conclusions: LBBAP can be performed safely in children with narrow QRS duration and stable pacing parameters. Cardiac dysfunction caused by long-term RVAP can be corrected by LBBAP quickly.
Soil eukaryote community shift but not composition is consistently recovered by diffe...
Shadi Eshghi Sahraei
Brendan Furneaux

Shadi Eshghi Sahraei

and 6 more

November 16, 2021
Long amplicon metabarcoding has opened the door for phylogenetic analysis of the largely unknown communites of microeukaryotes in soil. Here, we amplified and sequenced the ITS and LSU regions of the rDNA operon (around 1500 bp) from grassland soils using PacBio SMRT sequencing and evaluated the performance of three different methods for generation of operational taxonomic units (OTUs). The field site at Kungsängen Nature Reserve has drawn frequent visitors since Linnaeus’s time, and its species rich vegetation includes the largest population of Fritillaria meleagris in Sweden. To test the effect of different OTU generation methods, we sampled soils across an abrupt moisture transition that divides the meadow community into a Carex acuta dominated plant community with low species richness in the wetter part, which is visually distinct from the mesic-dry part that has a species rich grass-dominated plant community including a high frequency of F. meleagris. We used the moisture and plant community transition as a framework to investigare how detected belowground microeukaryotic community composition was influenced by OTU generation methods. Soil communities in both moisture regimes were dominated by protists, a large fraction of which were taxonomically assigned to Ciliophora (Alveolata) while 30-40% of all reads were assigned to kingdom Fungi. Ecological patterns were consistently recovered irrespective of OTU generation method used. However, different methods strongly affect richness estimates and the taxonomic and phylogenetic resolution of the characterized community with implications for how well members of the microeukaryotic communities can be recognized in the data.
Classification of AVNRT: an unresolved entity.
Yash Lokhandawala
Ashesh Halder

Yash Lokhandawala

and 1 more

November 16, 2021
The classification of AVNRT is based on HA and VA interval. Typical AVNRT is diagnosed in presence of HA ≤70 ms OR VA interval ≤60 ms and HA>70ms or VA >60ms is required to diagnose atypical AVNRT. This might be fallacious in some clinical situations. The septal VA and the “shortest” VA may be also different depending on clinical scenario .
Cutting through the Fat: Relationship Between Comorbidities and Arrhythmias in Hypert...
Alan Sugrue
David Lin

Alan Sugrue

and 1 more

November 15, 2021
Cutting through the Fat: Relationship Between Comorbidities and Arrhythmias in Hypertrophic Cardiomyopathy Alan Sugrue MBBCh, MSc; David Lin MD, FHRSCardiovascular Division, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PAManuscript word count: 1223Conflicts of interest: noneFunding: noneAddress for Correspondence:David Lin, MDHospital of the University of Pennsylvania3400 Spruce Street9 Founders PavilionPhiladelphia, PA 19104Email: david.lin@pennmedicine.upenn.edu
Idiopathic Ventricular Outflow Tract Arrhythmias: Avoid the Use of a Sledgehammer to...
Roy John
Alexander Perino

Roy John

and 1 more

November 15, 2021
Ventricular outflow is a common site for idiopathic PVCs and repetitive ventricular arrhythmias. Sites of origin of these arrhythmias may vary from the sites of earliest activation mapped. Better definition of the site of origin can help avoid unnecessary large volume ablation to suppress these arrhythmia.
Sudden Sensorineural Hearing Loss in a Hyperbaric Oxygen Chamber Employee Following P...
Henry Ideker
Ronald Walker

Henry Ideker

and 2 more

November 15, 2021
Sudden sensorineural hearing loss (SSNHL) is uncommon and oftentimes idiopathic. We describe the unique presentation of SSNHL in an HBO chamber employee following a parotidectomy, whose chief complaint was otalgia and aural fullness during dives. She ultimately recovered completely due to timely diagnosis and a high-dose steroid taper.
Activation of anti-SARS-CoV-2 human CTLs by extracellular vesicles engineered with th...
Francesco Manfredi
Chiara Chiozzini

Francesco Manfredi

and 6 more

November 15, 2021
We investigated an innovative anti-SARS-CoV-2 immune strategy finalized to oral administration of extracellular vesicles (EVs) inducing an anti-SARS-CoV-2 N CD8+ T cytotoxic lymphocyte (CTL) immune response. We previously reported that the SARS-CoV-2 N protein can be uploaded at high levels in EVs upon fusion with Nefmut, i.e., a biologically inactive HIV-1 Nef mutant incorporating into EVs at quite high levels. Here, we analyze the immunogenic properties in human cells of EVs engineered with SARS-CoV-2 N fused at the C-terminus of either Nefmut or a deletion mutant of Nefmut referred to as NefmutPL. Analysis of in vitro produced EVs proven the uploading of N protein also when fused with truncated Nefmut. Mice injected with DNA vectors expressing each fusion protein developed robust SARS-CoV-2 N-specific CD8+ T cell immune responses. When ex vivo human dendritic cells were challenged with EVs engineered with either fusion products, the induction of a robust N-specific CTL activity, as evaluated by both CD107a and trogocytosis assays, was observed. Through these data we achieved the proof-of-principle that engineered EVs can be instrumental to elicit anti-SARS-CoV-2 CTL immune response in human cells. This achievement represents a mandatory step towards the upcoming experimentations in pre-clinical models.
Prevalence of occult nodal metastases in squamous cell carcinoma of the temporal bone...
Daniele Borsetto
Ananth Vijendren

Daniele Borsetto

and 10 more

November 15, 2021
Objectives : Primary : To determine the rate of occult cervical metastasis in primary temporal bone squamous cell carcinomas (TBSSC). Secondary : to perform a subgroup meta-analysis of the risk of occult metastasis based on the clinical stage of the tumour and its risk based on corresponding levels of the neck Design : A systematic review and meta-analysis of papers searched through Medline, Cochrane, Embase, Scopus and Web of Science up to January 2021 to determine the pooled rate of occult lymph node/parotid metastases. Quality assessment of the included studies was assessed through the Newcastle-Ottawa scale. Setting : Centres around the world that perform surgery for TBSCC Participants : Patients with TBSCC Results : Overall, 9 out of 1034 screened studies met the inclusion criteria, for a total of 907 patients of which 388 had TBSCC. Out of the 191 patients who underwent a neck dissection, 21 had positive lymph nodes giving a pooled rate of occult metastases of 11% (95% CI: 7%-17%). When analysed using the Modified Pittsburg staging system, 21 pT2 cases had a pooled occult metastases rate of 3% (95% CI: 0%-21%), 27 pT3 cases had a pooled occult metastases rate of 12% (95% CI: 1%-60%), and 65 pT4 cases had a pooled occult metastases rate of 14% (95% CI: 7%-25%). Data available showed that most of the positive nodes were in Level II. Conclusion: The rate of occult cervical metastases in TBSCC increases based on the tumour (T) staging of the disease with majority of nodal disease found in level 2 of the neck.
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