Anaesthetic Management of Pulmonary Metastasectomy in a Patient Infected with Novel Corona Virus SARS-CoV-2.

Prioritisation of individual patients for thoracic surgeries gained importance during the current COVID-19 pandemic to ensure optimal utilisation of resources. We report a 76-year-old-male patient who presented to a tertiary care hospital in Muscat, Oman, 2020, with bilateral pulmonary metastasis. The patient underwent an urgent pulmonary metastasectomy with successful anaesthesia management in an elderly patient despite him testing positive for COVID-19 twice via real-time reverse transcription-polymerase chain reaction. At the 3-month follow-up some pulmonary abnormalities persisted but the patient was recovering well. This report discusses the rationale to perform surgery in this case and highlights the precautions taken for reducing aerosol generation during the various stages of anaesthesia.

The impact of the acceleration of COVID-19 vaccine deployment in two border regions in Oman.

Background: Among the challenges to public health systems imposed by coronavirus disease 2019 (COVID-19) have been vaccine scarcity and the prioritization of high-risk groups. Countries have been prompted to accelerate the pace of immunization campaigns against COVID-19 to deploy the immunization umbrella to the largest possible number of target groups. In this paper, we share the perspective of Oman regarding the impact of accelerating the administration of the first dose of the COVID-19 vaccine in one border governorate (Musandam) by comparison to another border governorate (Al-Buraimi) where this approach was not applied. Methods: Daily admissions data (April 10, 2020 to June 24, 2021) and vaccination data (January 1 to June 24, 2021) were collected systematically. For each governorate, the cumulative doses (first and second doses) and vaccination coverage were calculated daily. Results: Within 1 month, first dose vaccination coverage increased from 20% to 58% in Musandam, reducing the incidence of hospital admission by 75%. In comparison, vaccination coverage plateaued at 20% in Al-Buraimi, and the incidence of hospital admission increased by 500%. Conclusions: Given the peculiarity of the geographical location and being the first line of access for imported cases, border regions should be a priority for vaccine deployment as a preventive measure. The two different approaches reported here, implemented in broadly similar cross-border governorates, provide evidence of the significant effect of accelerating the first dose of vaccine in reducing hospitalizations.

Seroprevalence of SARS-CoV-2 antibodies in the general population of Oman: results from four successive nationwide sero-epidemiological surveys.

OBJECTIVE: To assess the seroprevalence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in Oman and longitudinal changes in antibody levels over time within the first 11 months of the coronavirus disease 2019 (COVID-19) pandemic. METHODS: This nationwide cross-sectional study was conducted as a four-cycle serosurvey using a multi-stage stratified sampling method from July to November 2020. A questionnaire was used and included demographics, history of acute respiratory infection and list of symptoms, COVID-19 contact, previous diagnosis or admission, travel history and risk factors. RESULTS: In total, 17,457 participants were surveyed. Thirty percent were female and 66.3% were Omani. There was a significant increase in seroprevalence throughout the study cycles, from 5.5% (4.8-6.2%) in Cycle 1 to 22% (19.6-24.6%) in Cycle 4. There was no difference in seroprevalence between genders, but significant differences were found between age groups. There was a transition of seroprevalence from being higher in non-Omanis than Omanis in Cycle 1 [9.1% (7.6-10.9%) vs 3.2% (2.6-3.9%)] to being higher in Omanis than non-Omanis in Cycle 4 [24.3% (21.0-27.9%) vs 16.8% (14.9-18.9%)]. There was remarkable variation in the seroprevalence of SARS-CoV-2 according to governorate. Close contacts of people with COVID-19 had a 96% higher risk of having the disease [adjusted odds ratio (AOR) 1.96, 95% confidence intervals (CI) 1.64-2.34]. Labourers had 58% higher risk of infection compared with office workers (AOR 1.58, 95% CI 1.04-2.35). CONCLUSION: This study showed a wide variation in the spread of SARS-CoV-2 across governorates in Oman, with higher estimated seroprevalence in migrants in the first two cycles. Prevalence estimates remain low and are insufficient to provide herd immunity.

Imported bancroftian filariasis discovered in a patient infected with Plasmodium falciparum: First case of concomitant parasitism in the Al-Buraimi Governorate, Oman.

Malaria and lymphatic filariasis (LF) are endemic in tropical and subtropical regions of sub-Saharan Africa, Asia, and Central and South America. Ninety-two percent (200 million) of malaria cases in 2017 were detected in the WHO African Region. This accounts for approximately 30% of the global burden of LF disease and includes 405.9 million people at risk in 39 out of 46 member countries. Anopheles species of mosquitoes transmit Wuchereria bancrofti in most parts of Africa. Our case of a 23-year-old Nigerian woman highlights incidental laboratory findings showing the first malaria/filariasis coinfection in the governorate (province). This coinfection was ascertained during the usual medical screening before recruitment in Oman, which is routinely conducted for every expatriate.

Nanoscale volume confinement and fluorescence enhancement with double nanohole aperture.

Diffraction ultimately limits the fluorescence collected from a single molecule, and sets an upper limit to the maximum concentration to isolate a single molecule in the detection volume. To overcome these limitations, we introduce here the use of a double nanohole structure with 25 nm gap, and report enhanced detection of single fluorescent molecules in concentrated solutions exceeding 20 micromolar. The nanometer gap concentrates the light into an apex volume down to 70 zeptoliter (10(-21) L), 7000-fold below the diffraction-limited confocal volume. Using fluorescence correlation spectroscopy and time-correlated photon counting, we measure fluorescence enhancement up to 100-fold, together with local density of optical states (LDOS) enhancement of 30-fold. The distinctive features of double nanoholes combining high local field enhancement, efficient background screening and relative nanofabrication simplicity offer new strategies for real time investigation of biochemical events with single molecule resolution at high concentrations.

Label-free free-solution nanoaperture optical tweezers for single molecule protein studies.

Nanoaperture optical tweezers are emerging as useful label-free, free-solution tools for the detection and identification of biological molecules and their interactions at the single molecule level. Nanoaperture optical tweezers provide a low-cost, scalable, straight-forward, high-speed and highly sensitive (SNR ∼ 33) platform to observe real-time dynamics and to quantify binding kinetics of protein-small molecule interactions without the need to use tethers or labeling. Such nanoaperture-based optical tweezers, which are 1000 times more efficient than conventional optical tweezers, have been used to trap and isolate single DNA molecules and to study proteins like p53, which has been claimed to be in mutant form for 75% of human cancers. More recently, nanoaperture optical tweezers have been used to probe the low-frequency (in the single digit wavenumber range) Raman active modes of single nanoparticles and proteins. Here we review recent developments in the field of nanoaperture optical tweezers and how they have been applied to protein-antibody interactions, protein-small molecule interactions including single molecule binding kinetics, and protein-DNA interactions. In addition, recent works on the integration of nanoaperture optical tweezers at the tip of optical fiber and in microfluidic environments are presented.

A label-free untethered approach to single-molecule protein binding kinetics.

Single molecule approaches provide rich real-time dynamics of molecular interactions that are not accessible to ensemble measurements. Previous single molecule studies have relied on labeling and tethering, which alters the natural state of the protein. Here we use the double-nanohole (DNH) optical tweezer approach to measure protein binding kinetics at the single molecule level in a label-free, free-solution (untethered) way. The binding kinetics of human serum albumin (HSA) to tolbutamide and to phenytoin are in quantitative agreement with previous measurements, and our single-molecule approach reveals a biexponential behavior characteristic of a multistep process. The DNH optical tweezer is an inexpensive platform for studying the real-time binding kinetics of protein-small molecule interactions in a label-free, free-solution environment, which will be of interest to future studies including drug discovery.

Observing single protein binding by optical transmission through a double nanohole aperture in a metal film.

We experimentally demonstrate protein binding at the single particle level. A double nanohole (DNH) optical trap was used to hold onto a 20 nm biotin-coated polystyrene (PS) particle which subsequently is bound to streptavidin. Biotin-streptavidin binding has been detected by an increase in the optical transmission through the DNH. Similar optical transmission behavior was not observed when streptavidin binding sites where blocked by mixing streptavidin with excess biotin. Furthermore, interaction of non-functionalized PS particles with streptavidin did not induce a change in the optical transmission through the DNH. These results are promising as the DNH trap can make an excellent single molecule resolution sensor which would enable studying biomolecular interactions and dynamics at a single particle/molecule level.

Double nanohole optical trapping: dynamics and protein-antibody co-trapping.

A double nanohole in a metal film can optically trap nanoparticles such as polystyrene/silica spheres, encapsulated quantum dots and up-converting nanoparticles. Here we study the dynamics of trapped particles, showing a skewed distribution and low roll-off frequency that are indicative of Kramers-hopping at the nanoscale. Numerical simulations of trapped particles show a double-well potential normally found in Kramers-hopping systems, as well as providing quantitative agreement with the overall trapping potential. In addition, we demonstrate co-trapping of bovine serum albumin (BSA) with anti-BSA by sequential delivery in a microfluidic channel. This co-trapping opens up exciting possibilities for the study of protein interactions at the single particle level.