Effects of endoscopic reprocessing on disinfection and its influential factors during coronavirus disease 2019 pandemic.

Objective To explore the effects of endoscopic reprocessing on disinfection and its influential factors under the coronavirus disease 2019 (COVID-19) pandemic. Methods A total of 450 endoscopes cleaned and disinfected according to Technical Specifications for Cleaning and Disinfection of Endoscopes from November 2019 to January 2020, and 450 endoscopes cleaned and disinfected according to The recommended procedure for cleaning and disinfection of gastrointestinal endoscopes during COVID-19 epidemic by Chinese Society of Digestive Endoscopology from February to April 2020 in the Second Affiliated Hospital of Chongqing Medical University were enrolled in the control group and observation group respectively by random number method. Both the control group and the observation group contained 200 gastroscopes, 200 enteroscopes and 50 ultrasound endoscopes. ATP fluorescence detection method and pour plate technique were used to evaluate the disinfection effect of endoscopes. Single factor analysis and multiple logistic regression were used to analyze the risk factors for unqualified sterilization after endoscopic reprocessing. Results The disinfection pass rates of gastroscopes, enteroscopes and ultrasound endoscopes in the observation group were not significantly different compared with those of the control group (P>0. 05). The sterilization pass rates and ATP test pass rates of gastroscopes, enteroscopes and ultrasound endoscopes in the observation group were significantly higher than those in the control group (all P<0. 05). Multivariate logistic regression analysis showed that non-strict implementation of endoscopic reprocessing (OR = 7. 96, 95%CI: 4. 55-22. 84, P<0. 001), non-standard operation (OR = 2. 26, 95%CI: 1. 24-5. 63, P<0. 001), insufficient concentration of disinfectant (OR = 5. 43, 95% CI: 2. 52-9. 02, P < 0. 001), insufficient concentration ratio of multi-enzyme solution (OR = 4. 38, 95% CI: 1. 95-8. 61, P < 0. 001), non-timely cleaning (OR= 2. 86, 95%CI: 1. 33-6. 42, P<0. 001), incomplete cleaning (OR = 3. 75, 95%CI: 1. 61-7. 49, P<0. 001) and improper endoscopic preservation (OR= 2. 12, 95%CI: 1. 36-4. 12, P<0. 001) were independent risk factors for unqualified sterilization after endoscopic reprocessing. Conclusion In COVID-19 pandemic, endoscope reprocessing can significantly improve the disinfection effect of endoscopes, worthy of further clinical promotion. The failure to strictly implement the reprocessing procedure is an important factor that may lead to unqualified sterilization.Copyright © 2021 The authors.

SARS-CoV-2 Invasion and Pathogenesis of COVID-19: A Perspective of Viral Receptors, Bradykinin, and Purinergic System

The present chapter focuses on the mechanisms of the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) infection, pathogenesis, and the possible therapeutic strategies targeted to the viral receptors, purinergic and kallikrein-kinin systems. SARS-CoV-2 spike protein binds with high affinity to the human ACE2 receptor on host cells, but it can also interact with other receptors and enzymes. Following viral infection, a plethora of subsequent molecular and cellular alterations occurs in the host. These alterations, which include the cytokine and bradykinin storms, as well as exacerbated ATP signalling, have been implicated in the genesis and progression of the signs and symptoms observed in COVID-19 patients. These routes and systems provide important targets for developing specific and effective anti-COVID-19 drugs, as well as reveal a novel understanding of pathogenesis and tropism of SARS-CoV-2. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2022.

Recent progress in online detection methods of bioaerosols

The aerosol transmission of coronavirus disease in 2019, along with the spread of other respiratory diseases, caused significant loss of life and property;it impressed upon us the importance of real-time bioaerosol detection. The complexity, diversity, and large spatiotemporal variability of bioaerosols and their external/internal mixing with abiotic components pose challenges for effective online bioaerosol monitoring. Traditional methods focus on directly capturing bioaerosols before subsequent time-consuming laboratory analysis such as culture-based methods, preventing the high-resolution time-based characteristics necessary for an online approach. Through a comprehensive literature assessment, this review highlights and discusses the most commonly used real-time bioaerosol monitoring techniques and the associated commercially available monitors. Methods applied in online bioaerosol monitoring, including adenosine triphosphate bioluminescence, laser/light-induced fluorescence spectroscopy, Raman spectroscopy, and bioaerosol mass spectrometry are summarized. The working principles, characteristics, sensitivities, and efficiencies of these real-time detection methods are compared to understand their responses to known particle types and to contrast their differences. Approaches developed to analyze the substantial data sets obtained by these instruments and to overcome the limitations of current real-time bioaerosol monitoring technologies are also introduced. Finally, an outlook is proposed for future instrumentation indicating a need for highly revolutionized bioaerosol detection technologies.

Changes in the proteomics of exhaled breath condensate under the influence of inhaled hydrogen in patients with post-COVID syndrome.

Aim. To study the effect of inhalation therapy with an active hydrogen (AH) on the protein composition of exhaled breath condensate (EBC) in patients with post-COVID syndrome (PCS). Material and methods. This randomized controlled parallel prospective study included 60 patients after coronavirus disease 2019 (COVID-19) with PCS during the recovery period and clinical manifestations of chronic fatigue syndrome who received standard therapy according to the protocol for managing patients with chronic fatigue syndrome (CFS). The patients were divided into 2 groups: group 1 (main) - 30 people who received standard therapy and AH inhalations (SUISONIA, Japan) for 10 days, and group 2 (control) - 30 medical workers who received only standard therapy. Patients in both groups were comparable in sex and mean age. All participants in the study were sampled with EBC on days 1 and 10. Samples were subjected to tryptic digestion and high-performance liquid chromatography combined with tandem mass spectrometry analysis using a nanoflow chromatograph (Dionex 3000) in tandem with a high-resolution time-of-flight mass spectrometer (timsTOF Pro). Results. A total of 478 proteins and 1350 peptides were identified using high resolution mass spectrometry. The number of proteins in samples after AH therapy, on average, is 12% more than before treatment. An analysis of the distribution of proteins in different groups of patients showed that only half of these proteins (112) are common for all groups of samples and are detected in EBC before, after, and regardless of hydrogen therapy. In addition to the qualitative difference in the EBC protein compositions in different groups, quantitative changes in the concentration of 36 proteins (mainly structural and protective) were also revealed, which together made it possible to reliably distinguish between subgroups before and after treatment. It is worth noting that among these proteins there are participants of blood coagulation (alpha-1-antitrypsin), chemokine- and cytokine-mediated inflammation, and a number of signaling pathways (cytoplasmic actin 2), response to oxidative stress (thioredoxin), glycolysis (glyceraldehyde-3- phosphate dehydrogenase), etc. Conclusion. The use of hydrogen therapy can contribute to the switching of a number of physiological processes, which may affect the success of recovery in PCS patients. In particular, the obtained results indicate the activation of aerobic synthesis of adenosine triphosphate in mitochondria by hydrogen therapy, which correlates well with the decrease in the blood lactate level detected by laboratory studies. At the same time, this therapy can inhibit pro-inflammatory activity, negatively affecting the coagulation and signaling pathways of integrins and apoptosis, and, in addition, activate protective pathways, tricarboxylic acid cycle, FAS signaling, and purine metabolism, which may be essential for effective recovery after COVID-19.Copyright © 2023 Vserossiiskoe Obshchestvo Kardiologov. All rights reserved.

SARS-CoV-2 Nsp13 Catalytic Efficiency is Regulated by ATP: Mg2+ Stoichiometry and Functional Cooperativity Among Nsp13 Molecules

Coronavirus disease 19 (COVID-19) is a highly contagious and lethal disease caused by the SARS-CoV-2 positive-strand RNA virus. Nonstructural protein 13 (Nsp13) is the highly conserved ATPase/helicase required for replication of the SARS-CoV-2 genome which allows for the infection and transmission of COVID-19. We biochemically characterized the purified recombinant SARS-CoV-2 Nsp13 helicase protein expressed using a eukaryotic cell-based system and characterized its catalytic functions, focusing on optimization of its reaction conditions and assessment of functional cooperativity among Nsp13 molecules during unwinding of duplex RNA substrates. These studies allowed us to carefully determine the optimal reaction conditions for binding and unwinding various nucleic acid substrates. Previously, ATP concentration was suggested to be an important factor for optimal helicase activity by recombinant SARS-CoV-1 Nsp13. Apart from a single study conducted using fixed concentrations of ATP, the importance of the essential divalent cation for Nsp13 helicase activity had not been examined. Given the importance of the divalent metal ion cofactor for ATP hydrolysis and helicase activity, we assessed if the molar ratio of ATP to Mg2+ was important for optimal SARS-CoV-2 Nsp13 RNA helicase activity. We determined that Nsp13 RNA helicase activity was dependent on ATP and Mg2+ concentrations with an optimum of 1 mM Mg2+ and 2 mM ATP. Next, we examined Nsp13 helicase activity as a function of equimolar ATP:Mg2+ ratio and determined that helicase activity decreased as the equimolar concentration increased, especially above 5 mM. We determined that Nsp13 catalytic functions are sensitive to Mg2+ concentration suggesting a regulatory mechanism for ATP hydrolysis, duplex unwinding, and protein remodeling, processes that are implicated in SARS-CoV-2 replication and proofreading to ensure RNA synthesis fidelity. Evidence is presented that excess Mg2+ impairs Nsp13 helicase activity by dual mechanisms involving both allostery and ionic strength. In addition, using single-turnover reaction conditions, Nsp13 unwound partial duplex RNA substrates of increasing doublestranded regions (16-30 base pairs) with similar kinetic efficiency, suggesting the enzyme unwinds processively in this range under optimal reaction conditions. Furthermore, we determined that Nsp13 displayed sigmoidal behavior for helicase activity as a function of enzyme concentration, suggesting that functional cooperativity and oligomerization are important for optimal activity. The observed functional cooperativity of Nsp13 protomers suggests the essential coronavirus RNA helicase has roles in RNA processing events beyond its currently understood involvement in the SARS-CoV-2 replication-transcription complex (RTC), in which it was suggested that only one of the two Nsp13 subunits has a catalytic function, whereas the other has only a structural role in complex stability. Altogether, the intimate regulation of Nsp13 RNA helicase by divalent cation and protein oligomerization suggests drug targets for modulation of enzymatic activity that may prove useful for the development of novel anti-coronavirus therapeutic strategies. This work was supported by the Intramural Training Program, National Institute on Aging (NIA), NIH, and a Special COVID-19 Grant from the Office of the Scientific Director, NIA, NIH.Copyright © 2023 The American Society for Biochemistry and Molecular Biology, Inc.

The SARS-CoV-2 Nsp13 Helicase Required for Coronavirus Replication Interacts with Structured Nucleic Acids in a Strand-Specific Manner and Catalyzes a Novel Protein-RNA Remodeling Activity Implicated in the Proofreading Mechanism of the Replication-Transc

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a single-stranded, positive-sense RNA virus responsible for COVID-19, requires a set of virally encoded nonstructural proteins that compose a replication-transcription complex (RTC) to replicate its 30 kilobase genome. One such nonstructural protein within the RTC is Nsp13, a highly conserved molecular motor ATPase/helicase. Upon purification of the recombinant SARS-CoV-2 Nsp13 protein expressed using a eukaryotic cell-based system, we biochemically characterized the enzyme by examining its catalytic functions, nucleic acid substrate specificity, and putative protein-nucleic acid remodeling activity. We determined that Nsp13 preferentially interacts with single-stranded (ss) DNA compared to ssRNA during loading to unwind with greater efficiency a partial duplex helicase substrate. The binding affinity of Nsp13 to nucleic acid was confirmed through electrophoretic mobility shift assays (EMSA) by determining that Nsp13 binds to DNA substrates with significantly greater efficiency than RNA. These results demonstrate strand-specific interactions of SARS-CoV-2 Nsp13 that dictate its ability to load and unwind structured nucleic acid substrates. We next determined that Nsp13 catalyzed unwinding of double-stranded (ds) RNA forked duplexes on substrates containing a backbone disruption (neutrally charged polyglycol linker (PGL)) was strongly inhibited when the PGL was positioned in the 5' ssRNA overhang, suggesting an unwinding mechanism in which Nsp13 is strictly sensitive to perturbation of the translocating strand sugar-phosphate backbone integrity. Furthermore, we demonstrated for the first time the ability of the coronavirus Nsp13 helicase to disrupt a high-affinity nucleic acid-protein interaction, i.e., a streptavidin tetramer bound to biotinylated RNA or DNA substrate, in a uni-directional manner and with a preferential displacement of the streptavidin complex from biotinylated ssDNA versus ssRNA. In contrast to the poorly hydrolysable ATP-gamma-S or non-hydrolysable AMP-PNP, ATP supports Nsp13-catalyzed disruption of the nucleic acidprotein complex, suggesting that nucleotide binding by Nsp13 is not sufficient for protein-RNA disruption and the chemical energy of nucleoside triphosphate hydrolysis is required to fuel remodeling of protein bound to RNA or DNA. Our results build upon structural studies of the SARS-CoV-2 RTC in which it was suggested that Nsp13 pushes the RNA polymerase (Nsp12) backward on the template RNA strand. Experimental evidence from our studies demonstrate that Nsp13 helicase efficiently remodels a large high affinity protein-RNA complex in a manner dependent on its intrinsic ATP hydrolysis function. We proposed that this novel biochemical activity of Nsp13 is relevant to its role in SARS-CoV-2 RNA processing functions and replication. It was proposed that Nsp13 facilitates proofreading during coronavirus replication when a mismatched base is inadvertently incorporated into the SARS-CoV-2 genome during replication to reposition the RTC so that the proofreading nuclease complex (Nsp14-Nsp10) can gain access and remove the nascently synthesized nucleotide to ensure polymerase fidelity. Our findings implicate a direct catalytic role of Nsp13 in protein-RNA remodeling during coronavirus genome replication beyond its duplex strand separation or structural stabilization of the RTC, yielding new insight into the proofreading mechanism. This work was supported by the Intramural Training Program, National Institute on Aging (NIA), NIH, and a Special COVID-19 Grant from the Office of the Scientific Director, NIA, NIH.Copyright © 2023 The American Society for Biochemistry and Molecular Biology, Inc.

Mitochondrial Dysfunction Is Associated with Post-Acute Sequelae of Covid-19

Background: Mitochondrial (mt) dysfunction has been described in acute severe SARS-CoV2 infection. It remains unclear whether the disturbances in mt are also present in post-acute sequelae of COVID-19 (PASC). Method(s): We analyzed cross-sectional data from participants without history of COVID and SARS-CoV2 antibody negative (COVID-), with documented prior COVID and full recovery (COVID+ PASC-), and with prior COVID with PASC as defined by the CDC (COVID+PASC+). Mt respiration was measured from peripheral blood mononuclear cells utilizing the Seahorse XFe96 analyzer. Generalized linear regression was used to compare estimates of mt and non-mt respirations, and unadjusted odds ratios using multinomial logistic regression to assess if mt respiration were associated with PASC. Result(s): For this analysis, 59 participants were enrolled, 71.19% (n=42) had a confirmed COVID-19 diagnosis. The overall mean age was 47.47 +/- 14.86 years, 69.49% (n=41) were females and 33.90% (n=20) were non-white race. There was no difference in demographics between participants with and without COVID (p>=0.72). Amongst all COVID+ participants, 19% (n=11) had hypertension and 8% (n=5) had diabetes. Among all COVID+, the median time between COVID diagnosis and study evaluation was 210 (IQR: 119, 453) days, and 50% (n=21) of COVID+ experienced persistent symptoms consistent with PASC. PASC participants had the highest observed values in non-mt respiration (21.57 +/- 10.77 pmol/min), basal respiration (38.95 +/- 17.58 pmol/min), proton leak (10.41 +/- 3.1), maximal respiration (103.91 +/- 58.63 pmol/min), spare respiratory capacity (64.96 +/- 41.82 pmol/min), and ATP production (28.55 +/-14.85 pmol/min). Basal respiration, ATP production, maximal respiration, and non-mt respiration were highest in PASC compared to COVID- (p<=0.02). There was marginal evidence (p=0.05) of a mean difference (8.09 pmol/min) in ATP production between COVID+PASC+ and COVID+PASC-, without differences in proton leak (p=0.23) or spare respiration capacity (p=0.07). Every unit increase in non-mt respiration, basal respiration, maximal respiration, and ATP production increased the predicted odds of PASC by 10.99, 5.6, 1.6 and 6.2%, respectively (Figure). Conclusion(s): Individuals with PASC are consuming more oxygen and producing more ATP in the PBMCs compared to controls. There also appears to be increased PBMC ATP production between PASC and COVID+. We hypothesize that this may reflect a crucial pathogenic mechanism in PASC that may be associated with ongoing inflammation. (Figure Presented).

Adipose tissue, systematic inflammation, and neurodegenerative diseases

Obesity is associated with several diseases, including mental health. Adipose tissue is distributed around the internal organs, acting in the regulation of metabolism by storing and releasing fatty acids and adipokine in the tissues. Excessive nutritional intake results in hypertrophy and proliferation of adipocytes, leading to local hypoxia in adipose tissue and changes in these adipokine releases. This leads to the recruitment of immune cells to adipose tissue and the release of pro-inflammatory cytokines. The presence of high levels of free fatty acids and inflammatory molecules interfere with intracellular insulin signaling, which can generate a neuroinflammatory process. In this review, we provide an up-to-date discussion of how excessive obesity can lead to possible cognitive dysfunction. We also address the idea that obesity-associated systemic inflammation leads to neuroinflammation in the brain, particularly the hypothalamus and hippocampus, and that this is partially responsible for these negative cognitive outcomes. In addition, we discuss some clinical models and animal studies for obesity and clarify the mechanism of action of anti-obesity drugs in the central nervous system.Copyright © 2023 Wolters Kluwer Medknow Publications. All rights reserved.

Size-classified monitoring of ATP bioluminescence for rapid assessment of biological distribution in airborne particulates.

The COVID-19 pandemic ignited massive research into the rapid detection of bioaerosols. In particular, nanotechnology-based detection strategies are proposed as alternatives because of issues in bioaerosol enrichment and lead time for molecular diagnostics; however, the practical implementation of such techniques is still unclear due to obstacles regarding the large research and development effort and investment for the validation. The use of adenosine triphosphate (ATP) bioluminescence (expressed as relative luminescence unit (RLU) per unit volume of air) of airborne particulate matter (PM) to determine the bacterial population as a representative of the total bioaerosols (viruses, bacteria, and fungi) has been raised frequently because of the high reponse speed, resolution, and compatibility with culture-based bioaerosol monitoring. On the other hand, additional engineering attempts are required to confer significance because of the size-classified (bioluminescence for different PM sizes) and specific (bioluminescence per unit PM mass) biological risks of air for providing proper interventions in the case of airborne transmission. In this study, disc-type impactors to cut-off aerosols larger than 1 µm, 2.5 µm, and 10 µm were designed and constructed to collect PM1, PM2.5, and PM10 on sampling swabs. This engineering enabled reliable size-classified bioluminescence signals using a commercial ATP luminometer after just 5 min of air intake. The simultaneous operations of a six-stage Andersen impactor and optical PM spectrometers were conducted to determine the correlations between the resulting RLU and colony forming unit (CFU; from the Andersen impactor) or PM mass concentration (deriving specific bioluminescence).

Evaluation of cardiac involvement in patients with clinical post-COVID-19 syndrome

Introduction: The underlying pathophysiology of Post-COVID-19 syndrome remains unknown, but increased cardiometabolic demand and state of mitochondrial dysfunction have emerged as candidate mechanisms. Cardiovascular magnetic resonance (CMR) provides insight into pathophysiological mechanisms underlying cardiovascular disease and 31-phosphorus magnetic resonance spectroscopy (31P-MRS) allows noninvasive assessment of the myocardial energetic state. Purpose(s): We sought to assess whether Post-COVID-19 syndrome is associated with abnormalities of myocardial structure, function, perfusion and tissue characteristics or energetic derangement. Method(s): Prospective case-control study. A total of 20 patients with a clinical diagnosis of Post-COVID-19 syndrome (seropositive) and no prior underlying cardiovascular disease (CVD) and ten matching controls underwent 31P-MRS and CMR at 3T at a single time point. (Figure 1) All patients had been symptomatic with acute COVID-19, but none required hospital admission. Result(s): Between the Post-COVID-19 syndrome patients and matched contemporary controls there were no differences in myocardial energetics (phosphocreatine to ATP ratio), in cardiac structure (biventricular volumes, left ventricular mass), function (biventricular ejection fractions, global longitudinal strain), tissue characterization (T1 and extracellular volume [ECV] fraction mapping, late gadolinium enhancement) or perfusion (myocardial rest and stress blood flow, myocardial perfusion reserve). One patient with Post-COVID-19 syndrome showed subepicardial hyperenhancement on the late gadolinium enhancement imaging compatible with prior myocarditis, but no accompanying abnormality in cardiac size, function, perfusion, ECV, T1, T2 mapping or energetics. This patient was excluded from statistical analyses. (Table 1) Conclusion(s): In this study, the overwhelming majority of patients with a clinical Post-COVID-19 syndrome with no prior CVD did not exhibit any abnormalities in myocardial energetics, structure, function, blood flow or tissue characteristics.

Does an Extraoral Suction Device Reduce Aerosol Generation and Prevent Droplet Exposure to the Examiner during Esophagogastroduodenoscopy?

Esophagogastroduodenoscopy (EGD) is an aerosol-generating procedure. A major challenge in the COVID-19 era is how to prevent the spread of aerosols and droplets in endoscopic units. We evaluated the effectiveness of an extraoral suction device in preventing indoor aerosol diffusion and droplet exposure for examiners. The study involved 61 patients who underwent EGD at our institution from 1 February to 31 March 2022. To determine whether aerosol spread increases before or after EGD examination with an extraoral suction device located in front of the patient's mouth, aerosols of 0.3, 0.5, 1, 3, 5, and 10 µm were measured with a handheld particle counter. The degree of contamination of the plastic gowns on the examiners was assessed using the rapid adenosine triphosphate test. The extraoral suction device significantly reduced the diffusion of large particles (3, 5, and 10 µm) after finishing the EGD examination. However, the diffusion of small particles (0.3 and 0.5 µm) was significantly increased. This extraoral suction device was effective in reducing large particle diffusion during EGD examination but was limited for minimizing small particle diffusion or droplet exposure to the examiner.

Evaluation of pulmonary function in post-COVID-19patients

Introduction: Changes in the lungs caused by COVID-19 can lead to impaired lung function. Recentrecommendations suggest that only patients with severe COVID-19 should be referred for pulmonary functionevaluation (PFT) 12 weeks after completion of treatment. The aim of this study was to evaluate PFT in bothmoderate and severe COVID-19 patients in the recommended period. Method(s): PFT was performed in 66 patients with no prior respiratory disease 3 months after COVID-19, analyzingthe forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), FEV1/FVC ratio, and thediffusing capacity for carbon monoxide (DLCO). Statistical analysis was done with the null hypothesis tested atp<0.05. Result(s): The study included 66 patients (45 males, 21 females) of mean age 56.1+/-11 years (30-75 years), with 28patients (42.4%) after severe COVID-19. The average values of PFT parameters are: FVC% 85.6+/-17.1 (52.1-124.9),FEV1% 88.2+/-17.6 (48.4-121.7), FEV1/FEV% 83.3+/-6.8 (64.3-97.3), DLCO% 72.6+/-19.1 (37-122). Reduced FVC was found in 13 patients (19.7%), while 3 patients (4.5%) had reduced FEV1/FVC values. DLCO was reduced in 25 patients (37.9%), but did not differ statistically significantly in relation to the severity of the disease (p>0.05). Conclusion(s): A significant number of patients had reduced diffusion capacity for carbon monoxide, although without statistically significant difference in relation to the disease severity. We conclude that the evaluation of pulmonary function is also important in patients after moderate COVID-19.

Use of ATP bioluminescence to survey the contamination of dental goggles in surgical removal of impacted mandibular third molars

The importance of protecting the eyes from infectious agents in patients' blood and saliva during dental surgery has long been known, but the global COVID-19 pandemic has made this even more important. The use of ATP bioluminescence to investigate the contamination of dental goggles during the surgical removal of impacted teeth in the present study indicates their importance for protecting the eyes from aerosols from the front, from above, and from the sides.Copyright © 2021 The Author(s)

Severe Prps1 Deficiency and Response to S-Adenosylmethionine and Nicotinamide Riboside Supplementation

Background: PRPS1 deficiency spectrum is an X-linked condition caused by pathogenic variants in PRPS1, which encodes for the PRPP enzyme involved in the purine synthesis pathway, among other metabolic pathways. Severely affected individuals, also known as Arts syndrome, have congenital sensorineural hearing loss, optic atrophy, developmental delays, ataxia, hypotonia, and recurrent infections. Infections often precipitate worsening of symptoms and many individuals pass away in childhood. Mildly to moderately affected individuals can have isolated hearing loss, also known as DFNX1, or hearing loss with later onset ataxia and optic neuropathy concerns, also known as CMTX5. Given the importance of PRPP in the role of purine synthesis as well as other cellular processes, including formation of NAD(P), supplementation of these pathways is a logical approach for these patients. 2 Arts syndrome patients were previously supplemented with S-adenosylmethionine, starting in mid-childhood, with improvement in infection severity and frequency, as well as stabilization of other symptoms. Recently another Arts syndrome patient was supplemented with S-adenosylmethionine and nicotinamide riboside, starting in early childhood, with improvement in infection frequency and developmental gains. Here we present a now 23 month old male patient with severe PRPS1 deficiency spectrum symptoms, who was started on S-adenosylmethionine and nicotinamide riboside supplementation. Result(s): This is a 23 month old male with developmental delay, retinal dystrophy, congenital bilateral sensorineural hearing loss, and hypotonia with a PRPS1 c.383A > T / p.Asp128Val likely pathogenic variant. He does not have a history of recurrent infections, however family reports relative isolation due to the Covid-19 pandemic. He sat unsupported at 10 months, crawled at 14 months, pulled to stand at 18 months, and is nonverbal. His uric acid testing was in the low range of normal. He had normal purine testing with low normal xanthine and hypoxanthine levels. At 19 months the patient started 20 mg/kg/d S-adenosylmethionine supplementation. At 20 months this was increased to 40 mg/kg/d S-adenosylmethionine and he started on 30 mg/kg/d nicotinamide riboside supplementation. Parents reported subjective improvement in strength and endurance with supplementation. He made significant developmental gains including walking with a walker. He had done well with occasional upper respiratory infections without regression in skills, worsening hypotonia, or increased respiratory needs. Unfortunately, very recently he had a cardiac arrest secondary to respiratory failure from rhinovirus/enterovirus and H. influzenzae pneumonia, for which he remains hospitalized at this time. Conclusion(s): This is the 4th reported patient with severe PRPS1 deficiency treated with S-adenosylmethionine supplementation and the 2nd reported patient treated with nicotinamide riboside supplementation. Both supplements have a limited side effect profile and have a biochemical basis for consideration in PRPS1 deficiency. He initially did well on supplementation with improvements in strength and endurance, as well as developmental gains, however his current trajectory remains to be seen. Unfortunately, NAD/NADP, ADP/ATP, and similar markers were unavailable to us and we plan to continue clinical monitoring on supplementation. Further studies are needed to evaluate the effectiveness of S-adenosylmethionine and nicotinamide riboside supplementation in these patients.Copyright © 2023

SG-APSIC1091: Assessment of compliance to cleaning of computers by healthcare workers (HCWs) using adenosine triphosphate (ATP) measurement

Objectives: HCWs are recommended to wipe the computers with alcohol wipes before clinical use. Compliance assessment by direct observation is resource intensive. We used ATP measurement as a surrogate to assess the compliance to preutilization cleaning of computers. Methods: We conducted a pilot study to determine the median relative light unit (RLU) value reflective of preutilization cleaning of the computers. We identified values of <250, 250–500, and >500 RLU to reflect cleaned, probably cleaned, and not cleaned computers, respectively. Subsequently, we conducted a cross-sectional study of the computers in the inpatient wards in Tan Tock Seng Hospital and National Centre for Infectious Diseases. Using 3M Clean-Trace ATP swabs, we tested 5 computers in each ward: 2 computers on wheels, 2 from the nursing station, and 1 at the patients' room entrance. All analyses were conducted using STATA version 15 software. Results: Between October 4 and 10, 2021, we collected 219 samples from 219 computers. Among them, 44 (20.1%) were cleaned, 49 (22.4%) were probably cleaned, and 126 (57.5%) computers were not cleaned. Higher compliance to computer cleaning was observed in COVID-19 wards [85 ATP samples;cleaned, 37 (43.5%);probably cleaned, 26 (30.6%);not cleaned, 22 (25.9%)] compared with non–COVID-19 wards [134 ATP samples;cleaned, 7 (5.2%);probably cleaned, 23 (17.2%);not cleaned, 104 (77.6%)] (P < .01). No significant difference was observed in compliance with cleaning computers between the ICU [30 ATP samples;cleaned, 7 (23.3%);probably cleaned, 4 (13.3%);not cleaned, 19 (63.3%)] and general wards [189 ATP samples;cleaned, 37 (19.6%);probably cleaned, 45 (23.8%);not cleaned, 107 (56.6%)] (P = .47). Conclusions: ATP swab tests can be used as a surrogate marker to assess compliance to pre-utilization cleaning of computers. Enhanced awareness of environmental hygiene may explain the higher compliance to computer cleaning observed in COVID-19 wards.

Rna-Dependent Rna Polymerase (Rdrp) Inhibitor Drugs against Sars-Cov-2: A Molecular Docking Study

Objective: SARS-CoV-2 associated viral pandemic was first reported in Wuhan, China, in December 2019. Due to the rapid increase in its pathogenicity, SARS-CoV-2 was declared a global pandemic by WHO on March 11, 2020. For that reason, determining the most attractive viral protein targets became a must. One of the most important target proteins is SARS-COV-2 RNA-dependent RNA polymerase (RdRp) on which COVID-19 depends in its replication process. This study aimed to examine the possible interactions between RdRp and the most promising RdRp nucleoside inhibitors especially Purine nucleoside analogs, to detect the most important residues that commonly interact with RdRp's inhibitors and to investigate whether if there any mutations have been observed so far in these residues or not. Material(s) and Method(s): Molecular docking studies were carried out using AutoDock Vina between SARS-CoV-2 RdRp and drugs approved against different viral RdRps (Galidesivir, Remdesivir, Ribavirin, Sofosbuvir, and Favipiravir) as well as physiological nucleotides (ATP and GTP). Based on the obtained results, a detailed surface-interaction analysis was also performed using Pymol and Discovery Studio Visualizer software for the models that exhibited the most suitable location and configuration in space. Result and Discussion: All the tested molecules were able to bind to SARS-CoV-2 RdRp successfully. Also, they all commonly interact with 9 different amino acids (Arg553, Arg555, Asp618, Asp623, Ser682, Asn691, Ser759, Asp760, and Asp761), and 3 different Template-primer RNA nucleotides (U10, A11, and U20) causing inhibition of viral RdRp via non obligate RNA chain termination.Copyright © 2022 University of Ankara. All rights reserved.

The mechanisms of action of ivermectin against SARS-CoV-2-an extensive review

Considering the urgency of the ongoing COVID-19 pandemic, detection of new mutant strains and potential re-emergence of novel coronaviruses, repurposing of drugs such as ivermectin could be worthy of attention. This review article aims to discuss the probable mechanisms of action of ivermectin against SARS-CoV-2 by summarizing the available literature over the years. A schematic of the key cellular and biomolecular interactions between ivermectin, host cell, and SARS-CoV-2 in COVID-19 pathogenesis and prevention of complications has been proposed.Copyright © 2022 Japan Antibiotics Research Association. All rights reserved.

Ketone Bodies and Cardiovascular Disease: An Alternate Fuel Source to the Rescue.

The increased metabolic activity of the heart as a pump involves a high demand of mitochondrial adenosine triphosphate (ATP) production for its mechanical and electrical activities accomplished mainly via oxidative phosphorylation, supplying up to 95% of the necessary ATP production, with the rest attained by substrate-level phosphorylation in glycolysis. In the normal human heart, fatty acids provide the principal fuel (40-70%) for ATP generation, followed mainly by glucose (20-30%), and to a lesser degree (<5%) by other substrates (lactate, ketones, pyruvate and amino acids). Although ketones contribute 4-15% under normal situations, the rate of glucose use is drastically diminished in the hypertrophied and failing heart which switches to ketone bodies as an alternate fuel which are oxidized in lieu of glucose, and if adequately abundant, they reduce myocardial fat delivery and usage. Increasing cardiac ketone body oxidation appears beneficial in the context of heart failure (HF) and other pathological cardiovascular (CV) conditions. Also, an enhanced expression of genes crucial for ketone break down facilitates fat or ketone usage which averts or slows down HF, potentially by avoiding the use of glucose-derived carbon needed for anabolic processes. These issues of ketone body utilization in HF and other CV diseases are herein reviewed and pictorially illustrated.

Prospective study on the risk of transmission due to droplets and aerosols during an endoscopic procedure and the usefulness of extraoral suction devices.

OBJECTIVES: Endoscopy poses a high risk of severe acute respiratory syndrome coronavirus 2 infection for medical personnel due to the dispersal of aerosols from the patient. We investigated the location and size of droplets generated during esophagogastroduodenoscopy (EGD) and endoscopic submucosal dissection (ESD), the contamination of the surrounding area before and after the procedures, and the effectiveness of using an extraoral suction device (Free arm arteo; TOKYO GIKEN, Inc., Tokyo, Japan). METHODS: Patients who consented to the study and underwent EGD or ESD between December 8, 2020, and April 15, 2021, at the National Cancer Center East Hospital were included. Adenosine triphosphate (ATP) hygiene monitoring tests and a particle counter were used for measurements. RESULTS: Assessments were performed on 22 EGD and 15 ESD cases. ATP hygiene monitoring tests showed significant elevations at three sites near the patient, and two sites 1.5 m away, for EGD, and at four sites near the patient and 1.5 m away for ESD. In both ESD and EGD, extraoral suction devices reduced the extent of the contamination. Particles <5 µm in size were generated during endoscopic procedures and dispersed from both the forceps hole and the patient's mouth. The extraoral suction device did not reduce the number of particles generated. CONCLUSIONS: During endoscopic procedures, cleaning the surrounding environment is important in addition to standard precautions the endoscopist and caregivers take. The use of extraoral suction devices can also potentially reduce contamination of the surrounding environment.

Effects of classroom cleaning on student health: a longitudinal study.

BACKGROUND: School districts across the world have been grappling with how to keep their schools open, students healthy, and prevent the spread of viruses in their communities. OBJECTIVE: The aims of this study included assessing both (1) the effectiveness of enhanced classroom cleaning and disinfecting protocol on surface biocontamination and (2) the associations between surface biocontamination and student absence due to illnesses. METHODS: Cleaning effectiveness was assessed using quantitative adenosine triphosphate (ATP) measurements during a 10-week study period in a sample of 34 public schools (15,814 students), of a district located in the Western US. The schools were randomly assigned to 17 intervention schools implementing enhanced cleaning and disinfecting protocol and 17 control schools cleaning as usual. General estimating equations (GEEs) were used for modeling associations between ATP levels and weekly aggregates of student absences due to respiratory and gastrointestinal illnesses, which were recorded by the schools according to district wide protocol. RESULTS: The weekly average ATP levels on logarithmic scale were 5.02 (SD 0.53) and 5.26 (SD 0.48) in the intervention and control schools, respectively, where the difference is statistically significant (p < 0.001). The probability of weekly absence due to gastrointestinal illness was significantly associated with ATP levels (parameter estimate 1.16, 95% CI 1.01-1.34, per unit (log) increase of weekly average ATP), where the model accounts for student level, gender, ethnic group, and socioeconomic status as well as for school level attendance, total absence ratio, and ventilation adequacy in classrooms. Associations were not found between ATP levels and weekly probability of any absence, or absence due to respiratory illness. SIGNIFICANCE: Enhanced cleaning resulted in a significantly lower level of biocontamination on desktops in the intervention group. In addition, a statistically significant association was established between ATP levels on classroom desks and probability of absence due to gastrointestinal illness. IMPACT: We found that enhanced cleaning protocol, including bi-weekly cleaning of classroom desks, as well as training of custodians and teachers, monitoring of effectiveness, and feedback, yielded a moderate but statistically significantly lower level of biocontamination on desktops, indicated by quantitative ATP monitoring. Within the range of weekly average desktop ATP levels observed, the probability of reported absence due to gastrointestinal illness is estimated to increase from 0.021 to 0.026. Based on the results, enhanced surface cleaning and monitoring its effectiveness is a possible district, state, or even national level policy to support healthy school environments.