Daylily (Hemerocallis fulva Linn.) flowers improve sleep quality in human and reduce nitric oxide and interleukin-6 production in macrophages.

The flowers of daylily (Hemerocallis fulva Linn.) have been used as vegetable and medicinal herb for thousands of years in Taiwan and eastern Asia. Daylily flowers have been demonstrated to exert several biomedical properties. In this study, we provided the evidences show that daylily flowers exert anti-inflammatory activity in vitro and improved the sleep quality in vivo. We demonstrated that adult volunteers received water extract of daylily flowers improved sleep quality, sleep efficiency and daytime functioning, while sleep latency was reduced, compared to the adult volunteers received water. In addition, we demonstrated that aqueous and ethanol extracts of daylily flowers inhibited nitric oxide and interleukin-6 production in lipopolysaccharide-activated macrophages. Furthermore, the quantitative high performance liquid chromatography-based analysis showed the rutin content of the aqueous extract, ethanolic extract, ethyl acetate fractions of ethanolic extract, and water fractions of ethanolic extract were 7.27, 23.30, 14.71, and 57.43 ppm, respectively. These results indicate that daylily flowers have the potential to be a nutraceutical for improving inflammatory-related diseases and sleep quality in the future.

SARS-CoV-2 Outbreak Dynamics in an Isolated US Military Recruit Training Center With Rigorous Prevention Measures.

BACKGROUND: Marine recruits training at Parris Island experienced an unexpectedly high rate of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, despite preventive measures including a supervised, 2-week, pre-entry quarantine. We characterize SARS-CoV-2 transmission in this cohort. METHODS: Between May and November 2020, we monitored 2,469 unvaccinated, mostly male, Marine recruits prospectively during basic training. If participants tested negative for SARS-CoV-2 by quantitative polymerase chain reaction (qPCR) at the end of quarantine, they were transferred to the training site in segregated companies and underwent biweekly testing for 6 weeks. We assessed the effects of coronavirus disease 2019 (COVID-19) prevention measures on other respiratory infections with passive surveillance data, performed phylogenetic analysis, and modeled transmission dynamics and testing regimens. RESULTS: Preventive measures were associated with drastically lower rates of other respiratory illnesses. However, among the trainees, 1,107 (44.8%) tested SARS-CoV-2-positive, with either mild or no symptoms. Phylogenetic analysis of viral genomes from 580 participants revealed that all cases but one were linked to five independent introductions, each characterized by accumulation of mutations across and within companies, and similar viral isolates in individuals from the same company. Variation in company transmission rates (mean reproduction number R 0 ; 5.5 [95% confidence interval [CI], 5.0, 6.1]) could be accounted for by multiple initial cases within a company and superspreader events. Simulations indicate that frequent rapid-report testing with case isolation may minimize outbreaks. CONCLUSIONS: Transmission of wild-type SARS-CoV-2 among Marine recruits was approximately twice that seen in the community. Insights from SARS-CoV-2 outbreak dynamics and mutations spread in a remote, congregate setting may inform effective mitigation strategies.

Oriented Immobilization of Single-Domain Antibodies Using SpyTag/SpyCatcher Yields Improved Limits of Detection.

Single-domain antibodies (sdAb), recombinantly produced variable heavy domains derived from the unconventional heavy chain antibodies found in camelids, provide stable, well-expressed binding elements with excellent affinity that can be tailored for specific applications through protein engineering. Complex matrices, such as plasma and serum, can dramatically reduce assay sensitivity. Thus, to achieve highly sensitive detection in complex matrices a highly efficient assay is essential. We produced sdAb as genetically linked dimers, and trimers, each including SpyTag at their C-terminus. The constructs were immobilized onto dyed magnetic microspheres to which SpyCatcher had been coupled and characterized in terms of their performance as capture reagents in sandwich assays. Initial tests on the ability of oriented monomer, dimer, and trimer captures to improve detection versus unoriented constructs in an assay for staphylococcal enterotoxin B spiked into buffer showed the oriented dimer format provided the best sensitivity while offering robust protein production. Thus, this format was utilized to improve a sdAb-based assay for the detection of dengue virus (DENV) nonstructural protein 1 (NS1) in serum. Detection of NS1 from each of the four DENV serotypes spiked into 50% normal human serum was increased by at least a factor of 5 when using the oriented dimer capture. We then demonstrated the potential of using the oriented dimer capture to improve detection of NS1 in clinical samples. This general method should enhance the utility of sdAb incorporated into any diagnostic assay, including those for high consequence pathogens.

Adsorption Behavior of Recyclable Magnetites with N-Components for Adsorption of Copper Ion.

Recyclable magnetites with thioureido group (poly-allyl-thiourea/oleic acid/magnetite, PAT-adsorbent) and amine functional group (ethylenediamine/methyl methacrylate/oleic acid/magnetite, EDA-adsorbent) were synthesized by modifying magnetite with oleic acid, methyl methacrylate, allyl thiourea and ethylenediamine. PAT-adsorbent and EDA-adsorbent were used and compared for adsorption of copper ions in a batch system due to the existence of amino group (-NH2) both on thioureido group and amine functional group. The kinetics of both PAT-adsorbent and EDA-adsorbent were evaluated utilizing pseudo-first-order and pseudo-second-order kinetic models. The equilibrium data was analyzed and compared using the Langmuir and Freundlich isotherm models. The maximum adsorption capacity (Qm) of PAT-adsorbent (19.126 mg g-1) was higher than that of EDA-adsorbent (7.096 mg g-1). As compared to EDA-adsorbent the magnetic adsorbent (PAT-adsorbent) with good desorption performance (>85% desorption efficiency) and easily reuse (>85% recovery by magnetic force) was the important factors for its potential practical application.

Adsorption of Phosphate in Aqueous Solution by Magnetite Modified with Diethylenetriamine.

A magnetic adsorbent, amine-functionalized silica magnetite (NH2-Al/SiO2/Fe3O4), has been synthesized to behave as an cationic adsorbent by adjusting the pH value of the aqueous solution to make amino groups protonated. NH2-Al/SiO2/Fe3O4 was used to adsorb phosphate ions in an aqueous solution in a batch system, and the maximum adsorption were found to occur at pH 3.0. The adsorption equilibrium data were all fitted the Langmuir isotherm equation reasonably well, and the maximum adsorption capacities of phosphate ions were more than 40 mg g(-1) and increased with elevating temperature. The enthalpy (ΔH0) and entropy (ΔS0) values of NH2-Al/SiO2/Fe3O4 with the adsorption reaction of phosphate ions were 11.98 KJ mol(-1) and 0.095 KJ (T mol)(-1), respectively. A pseudo-second-order model also could best describe the adsorption kinetics, and the derived activation energy for phosphate ions was 20.2 kJ mol(-1). The optimum condition to desorb phosphate ions from NH2-Al/SiO2/Fe3O4 is provided by a solution with 0.05 M NaOH.

A single domain antibody-based Luminex assay for the detection of SARS-CoV-2 in clinical samples.

Within the past decade, single domain antibodies (sdAbs) have been recognized as unique affinity binding reagents that can be tailored for performance in a variety of immunoassay formats. Luminex MagPlex color-coded magnetic microspheres provide a high-throughput platform that enables multiplexed immunoassays. We developed a MagPlex bead-based assay for the detection of SARS-CoV-2, using sdAbs against SARS-CoV-2 nucleocapsid (N) protein in which we engineered the sdAb capture reagents to orient them on the beads. The oriented sdAbs provided an increase in sensitivity over randomly oriented sdAbs for samples of N diluted in buffer, which also translated into better detection of SARS-CoV-2 in clinical samples. We assessed the specificity of the assay by examining seasonal coronavirus clinical samples. In summary, we provide a proof-of-concept that a bead-based assay using sdAbs to detect SARS-CoV-2 is feasible and future research combining it with other sdAb-coated beads that can detect other viruses may provide a useful diagnostic tool.

Influence of calcination temperature on structure, magnetic property, photocatalytic activity and recovery of recyclable photocatalysts.

The photocatalytic oxidation of titanium dioxide is conducted in a suspension of submicrometer-sized particles, and an additional separation step is required to recover these catalyst particles from treated water, which presents a major drawback in treating wastewater. In this study, magnetic photocatalysts of spinel structure Fe3O4 coated with SiO2 and TiO2 by employing various heat treatments were synthesized and their characterization was carried out by thermogravimetric analysis, X-ray diffraction, vibrating sample magnetometry, and Fourier transform infrared spectroscopy. Furthermore, the reaction behavior in photocatalytic processes involving photocatalysts of porous composite for treating wastewater were analyzed to enhance their activity and recovery. The results showed that the calcination temperatures of the magnetic photocatalysts significantly affect their properties, i.e., rutile ratio, magnetization, surface area, and photocatalytic activity. The photocatalytic activity of these catalysts was measured using the decomposition of benzoic acid, which can be well modeled by the Langmuir-Hinshelwood kinetic equation. Furthermore, because of the paramagnetic behaviors of the prepared TiO2/SiO2/Fe3O4, these magnetic photocatalyst could be easily recovered by applying a magnetic field.

Performance Evaluation of Five Rapid At-Home COVID-19 Antigen Tests against the Omicron Variant.

Rapid coronavirus disease 2019 (COVID-19) antigen tests can be used to aid in quickly identifying positive cases, which can help mitigate the spread of COVID-19 infection. Using previously characterized Omicron-positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), non-Omicron-positive SARS-CoV-2, and negative samples, we evaluated five brands of at-home rapid COVID-19 antigen tests (On/Go at-home COVID-19 rapid antigen self-test, iHealth COVID-19 antigen rapid test, QuickVue SARS antigen test, Abbott BinaxNOW COVID-19 card home test, and InBios SCoV-2 Ag detect rapid self-test). Our results showed that these rapid tests had similar levels of sensitivity to Omicron and non-Omicron variants (On/Go, 76.4% and 71.0%; iHealth, 73.0% and 71.0%; QuickVue, 84.3% and 74.3%; BinaxNOW, 69.7% and 71.0%; and InBios, 66.3% and 64.5%, respectively). In conclusion, rapid COVID-19 antigen tests can continue to be used as part of public health measures to combat the spread of the Omicron variant, as their sensitivity was not significantly affected. IMPORTANCE The emergence of the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is due to mutations as part of the virus evolution process. These mutations might affect the sensitivity of diagnostic tests that are currently being used to detect the virus. Because rapid coronavirus disease 2019 (COVID-19) antigen tests are commonly used in the general population, it is important to assess their performance in detecting the Omicron variant. Here, we compared the performance of five brands of rapid tests against Omicron and non-Omicron variants using nasopharyngeal swab samples in viral transport media. Our result found no difference in their performance, suggesting no reduction in sensitivity when used to detect the Omicron variant.

Successful multidisciplinary therapy for a patient with liver metastasis from ascending colon adenocarcinoma: A case report and review of literature.

BACKGROUND: Liver metastasis is the most common form of distant metastasis in colorectal cancer, and the only possible curative treatment for patients with colorectal liver metastases (CRLM) is hepatectomy. However, approximately 25% of patients with CRLM have indications for liver resection at the initial diagnosis. Strategies aimed at downstaging large or multifocal tumors to enable curative resection are appealing. CASE SUMMARY: A 42-year-old man was diagnosed with ascending colon cancer and liver metastases. Due to the huge lesion size and compression of the right portal vein, the liver metastases were initially diagnosed as unresectable lesions. The patient was treated with preoperative transcatheter arterial chemoembolization (TACE) consisting of 5-fluorouracil/Leucovorin/oxaliplatin/Endostar®. After four courses, radical right-sided colectomy and ileum transverse colon anastomosis were performed. Postoperatively, the pathological analysis revealed moderately differentiated adenocarcinoma with necrosis and negative margins. Thereafter, S7/S8 partial hepatectomy was performed after two courses of neoadjuvant chemotherapy. Pathological examination of the resected specimen revealed a pathologically complete response (pCR). Intrahepatic recurrence was detected more than two months after the operation, and the patient was then treated with TACE consisting of irinotecan/Leucovorin/fluorouracil therapy plus Endostar®. Subsequently, the patient was treated with a γ-knife to enhance local control. Notably, a pCR was reached, and the patient's overall survival time was > 9 years. CONCLUSION: Multidisciplinary treatment can promote the conversion of initially unresectable colorectal liver metastasis and facilitate complete pathological remission of liver lesions.

Asia-Pacific multicentre randomized trial of laparoscopic versus open major hepatectomy for hepatocellular carcinoma (AP-LAPO trial).

BACKGROUND: Hepatocellular carcinoma is the sixth most common malignancy in the world. Major hepatectomy (resection of greater than or equal to three liver segments) is needed if a tumour is large or close to major blood vessels. Despite low mortality, open major hepatectomy is associated with high rates of tumour recurrence that limits survival. Laparoscopic major hepatectomy has been proposed as an alternative approach with potential oncological benefits. This study compares laparoscopic major hepatectomy with open major hepatectomy for hepatocellular carcinoma in a randomized trial. METHODS: The Asia-Pacific multicentre randomized trial of laparoscopic versus open major hepatectomy for hepatocellular carcinoma (AP-LAPO trial) is an open-labelled multicentre randomized trial to be conducted in five centres in the Asia-Pacific region. The study will test the hypothesis that laparoscopic major hepatectomy for hepatocellular carcinoma is associated with less tumour recurrence and better survival compared with open major hepatectomy; the primary outcome being 2-year recurrence-free survival. Secondary outcomes include hospital mortality, postoperative complications according to the Clavien-Dindo classification, time to functional recovery, quality of life, long-term survival, and postoperative serum surgical stress-related cytokines. RESULTS AND CONCLUSION: The AP-LAPO trial will determine whether laparoscopic major hepatectomy offers oncological benefits to patients with hepatocellular carcinoma compared with open major hepatectomy. REGISTRATION NUMBER: NCT04852211 (http://www.clinicaltrials.gov) registered on 21 April 2021. PROTOCOL VERSION: AP-LAPO trial version 01 (1 December 2021).

Magnetic nanoadsorbents with amino-functionalized polymers for magnetic separation removal of copper ion.

The adsorption of copper ions on magnetic adsorbents with amino-functionalized polymers (DETA/SiO2/Fe3O4) has been investigated. In addition, the structure and characterization of magnetic nano-adsorbents were confirmed using FTIR, TGA, TEM, VSM, and BET. The results showed that DETA/SiO2/Fe3O4 exhibited a paramagnetic behaviour and could be easily recovered and quickly separated from a suspension solution. The optimum pH level for adsorption of copper ions was proposed to be in the range of pH level from 5 to 6, and the maximum adsorption capacity (qm) and activated energy (Ea) at 298 K was 13.459 mg g-1 and 22.421 kJ mol-1, respectively. The copper ions adsorption behaviour by DETA/SiO2/Fe3O4 was in good agreement with the Langmuir isotherm rather than Freundlich equation. A pseudo-second-order model could best describe the adsorption kinetics, and the optimal condition of copper ions desorption (99%) from DETA/SiO2/Fe3O4 was provided by 1.0 M HNO3. The novel magnetic nano-adsorbents could not only be regenerated by HNO3 solutions but also reused by the recovery of magnetic force without requiring further downstream treatment.

Leptospirosis and Rickettsial Diseases Sero-Conversion Surveillance Among U.S. Military Personnel in Honduras.

INTRODUCTION: Leptospirosis and rickettsial diseases are global zoonotic diseases. In severe infection cases, mortality can range from 10% to 30%. Currently most epidemiological data available are based on outbreak investigations and hospital-based studies from endemic countries. The U.S. soldiers at military bases in these countries are highly vulnerable due to the fact that most of them are immunologically naïve to these pathogens. No risk assessment of leptospirosis and rickettsial diseases among U.S. military personnel in Honduras is currently available. This study was aimed at determining the prevalence of leptospirosis and rickettsial diseases in U.S. military personnel deployed to Honduras using serological assays. MATERIALS AND METHODS: A cohort of pre- and post-deployment sera from the most recent 1,000 military personnel stationed in Honduras for at least 6 months between 2000 and 2016 was identified for this study. Serum specimens from these eligible subjects were retrieved. All post-deployment serum specimens were screened at a dilution of 1:100 for the presence of IgG antibodies to Leptospira and Rickettsia pathogens. The pre-deployment sera from those individuals with post-deployment IgG antibodies above cutoff (i.e., seropositive) were tested to determine seroconversion. Seroconversion was defined as conversion of an optical density value from below the cutoff (i.e., negative) in a pre-deployed specimen to above the cutoff (i.e., positive) in a post-deployed specimen at a titer of 100. RESULTS: The seropositive post-deployment specimens for antibodies against Leptospira (causing leptospirosis), Rickettsia typhi (causing murine typhus [MT]), spotted fever group rickettsioses (SFGR, causing SFG Rickettsia), Orientia tsutsugamushi (causing scrub typhus [ST]), and Coxiella burnetii (causing Q fever [QF]) were 11.6%, 11.3%, 6%, 5.6%, and 8.0%, respectively. The seroconverted rate in those assigned to Honduras from 2000 to 2016 was 7.3%, 1.9%, 3.9%, 4.3%, and 2.7% for leptospirosis, MT, SFGR, ST, and QF, respectively. Among the seroconverted specimens, 27 showed seroconversion of at least two antibodies. These seroconverted individuals accounted for 8.8% (3 out of 34) of the personnel who looked for medical attention during their deployment. CONCLUSIONS: Our results suggest a leptospirosis seroconversion rate of 7.3%, which is higher than the 0.9% and 3.9% seroconversion in Korea and Japan, respectively. The higher rate of seroconversion indicates potential risk of Leptospira exposure. Additional testing of water samples in the pools and pits around the training sites to locate the infected areas is important to eliminate or reduce future exposure to Leptospira during trainings. The rates of seroconversion for ST, MT, spotted fever Rickettsia, and QF were 4.3%, 1.9%, 3.9%, and 2.7%, respectively, indicating the potential exposure to a variety of rickettsial-related pathogens. Testing of vectors for rickettsial pathogens in the areas could inform effective vector control countermeasures to prevent exposure. Proper precaution and protective measures are needed to better protect military personnel deployed to Honduras.

Preparation of curcumin-loaded liposome with high bioavailability by a novel method of high pressure processing.

Curcumin has been incorporated for the development of new products with applicability in food, pharmaceutical and cosmetic fields in Asia, due to the traits of anti-oxidation and anti-inflammatory. In the application of food engineering, high-pressure processing (HPP) can destroy non-covalent bonds and use as a method to inactivate bacteria for extending the perseveration of food. Thus, this study focuses on a novel approach for the microencapsulation of curcumin by the combination of ethanol injection and HPP at the room temperature for stabilizing pure curcumin in aqueous solutions and in liposome. The results revealed that the most optimal curcumin-liposome was prepared by HPP at operational pressure of 200 MPa within 5 mins holding time to obtain the minimum particle size of 281.9 nm, encapsulation efficiency of 87.25% and polydispersity index (PDI) of 0.23. Particle size could reduce to nanoscale (70.65 nm) after 0.5% addition of Tween 80, but the encapsulation efficiency spontaneously decreased to 45.05%. It is an option to produce liposome with nanosize and uniform distribution for the consideration of high drug delivery. Conclusively, HPP process could not only effectively decrease particle size and PDI of liposome but also efficiently sterilize bacteria around concentration of 103 CFU/g.

Biocompatibile nanofiber based membranes for high-efficiency filtration of nano-aerosols with low air resistance.

Particulate matter (PMs) from combustion emissions (traffic, power plant, and industries) and the novel coronavirus (COVID-19) pandemic have recently enhanced the development of personal protective equipment against airborne pathogens to protect humans' respiratory system. However, most commercial face masks still cannot simultaneously achieve breathability and high filtration of PMs, bacteria, and viruses. This study used the electrospinning method with polyimide (PI) and polyethersulfone (PES) solutions to form a nanofiber membrane with low-pressure loss and high biocompatibility for high-efficiency bacteria, viruses, and nano-aerosol removal. Conclusively, the optimized nano-sized PI/PES membrane (0.1625 m2/g basis weight) exhibited conspicuous performance for the highest filtration efficiency towards PM from 50 to 500 nm (99.74 %), good filter quality of nano-aerosol (3.27 Pa-1), exceptional interception ratio against 100-nm airborne COVID-19 (over 99 %), and non-toxic effect on the human body (107 % cell viability). The PI/PES nanofiber membrane required potential advantage to form a medical face mask because of its averaged 97 % BEF on Staphylococcus aureus filiation and ultra-low pressure loss of 0.98 Pa by referring ASTM F2101-01. The non-toxic PI/PES filters provide a new perspective on designing excellent performance for nano-aerosols from air pollution and airborne COVID-19 with easy and comfortable breathing under ultra-low air flow resistance.

Lessons Learned From a Prospective Observational Study of U.S. Marine Recruits During a Supervised Quarantine, Spring‒Fall 2020.

Introduction: Quarantining is commonly used to mitigate the spread of SARS-CoV-2. However, questions remain regarding what specific interventions are most effective. Methods: After a 2-week home quarantine, U.S. Marine Corps recruits underwent a supervised 2-week quarantine at a hotel from August 11 to September 21, 2020. All recruits were assessed for symptoms through oral questioning and had their temperatures checked daily. Study participants answered a written clinical questionnaire and were tested for SARS-CoV-2 by polymerase chain reaction shortly after arrival in quarantine and on Days 7 and 14. The results were compared with those of a previously reported Marine-supervised quarantine at a college campus from May until July 2020 utilizing the same study, laboratory, and statistical procedures. Results: A total of 1,401 of 1,514 eligible recruits (92.5%) enrolled in the study, 93.1% of whom were male. At the time of enrollment, 12 of 1,401 (0.9%) participants were polymerase chain reaction positive for SARS-CoV-2, 9 of 1,376 (0.7%) were positive on Day 7, and 1 of 1,358 (0.1%) was positive on Day 14. Only 12 of 22 (54.5%) participants endorsed any symptoms on a study questionnaire, and none of the participants had an elevated temperature or endorsed symptoms during daily screening for SARS-CoV-2. Participation rate (92%) was much greater than the approximately 58.8% (1,848 of 3,143) rate observed in the previous Marine-supervised college campus quarantine, suggesting the changing attitudes of recruits during the pandemic (p<0.001). Approximately 1% of participants were quantitative polymerase chain reaction positive after self-quarantine in both studies. Conclusions: Key findings include the shifting attitudes of young adults during the pandemic, the limitations of self-quarantine, and the ineffectiveness of daily temperature and symptom screening to identify SARS-CoV-2‒positive recruits.

Independent Evaluation of Two Prototype Immunochromatographic Tests for Dengue Fever Developed by InBios.

INTRODUCTION: Dengue fever, caused by any of the four dengue viruses (DENV1-4), is endemic in more than 100 countries around the world. Each year, up to 400 million people get infected with dengue virus. It is one of the most important arthropod-borne viral diseases. Dengue's global presence poses a medical threat to deploying military personnel and their dependents. An accurate diagnosis followed by attentive supportive care can improve outcomes in patients with severe dengue disease. Dengue diagnostic tests based on PCR and ELISA platforms have been developed and cleared by the U.S. FDA. However, these diagnostic assays are laborious and usually require highly trained personnel and specialized equipment, which presents a significant challenge when conducting operations in austere and resource-constrained areas. InBios International, Inc. (Seattle, WA) has developed two rapid and instrument-free immunochromatographic test prototype devices (multiplex and traditional formats) for dengue diagnosis. MATERIALS AND METHODS: To determine the performance of the InBios immunochromatographic tests, 183 clinical samples were tested on both prototype devices. Both assays were performed without any instruments and the results were read in 20 minutes. RESULTS: The traditional format had better overall performance (sensitivity: 97.4%; specificity: 90%) than the multiplex format (sensitivity: 86.9%; specificity: 63.3%). The traditional format was superior in serotype-specific detection with 100% overall sensitivity for DENV1, DENV3, and DENV4 and 93.3% sensitivity for DENV2 compared to the multiplex format (91.7%, 78.3%, 83.3%, and 96.3% for DENV1, 2, 3, and 4, respectively). The traditional format was easier to read than the multiplex format. The multiplex format was simpler and faster to set up than the traditional format. CONCLUSIONS: The InBios traditional format had a better overall performance and readability profile than the multiplex format, while the multiplex format was easier to set up. Both formats were highly sensitive and specific, were easy to perform, and did not require sophisticated equipment. They are ideal for use in resource-limited settings where dengue is endemic. Based on our overall assessment, the traditional format should be considered for further development and used in the upcoming multicenter clinical trial toward FDA clearance.

Enhanced Immunogenicity of Inactivated Dengue Vaccines by Novel Polysaccharide-Based Adjuvants in Mice.

Dengue fever, caused by any of four dengue viruses (DENV1-4), is a major global burden. Currently, there is no effective vaccine that prevents infection in dengue naïve populations. We tested the ability of two novel adjuvants (Advax-PEI and Advax-2), using aluminum hydroxide (alum) as control, to enhance the immunogenicity of formalin- or psoralen-inactivated (PIV or PsIV) DENV2 vaccines in mice. Mice were vaccinated on days 0 and 30, and serum samples were collected on days 30, 60, 90, and 101. Neutralizing antibodies were determined by microneutralization (MN) assays, and the geometric mean 50% MN (MN50) titers were calculated. For the PIV groups, after one dose MN50 titers were higher in the novel adjuvant groups compared to the alum control, while MN50 titers were comparable between the adjuvant groups after the second dose. For the PsIV groups, both novel adjuvants induced higher MN50 titers than the alum control after the second dose. Spleen cells were collected on days 45 and 101 for enzyme-linked immunospot (ELISPOT) for IFNγ and IL4. Both PIV and PsIV groups elicited different degrees of IFNγ and IL4 responses. Overall, Advax-2 gave the best responses just ahead of Advax-PEI. Given Advax-2's extensive human experience in other vaccine applications, it will be pursued for further development.

Validation of SARS-CoV-2 pooled testing for surveillance using the Panther Fusion® system: Impact of pool size, automation, and assay chemistry.

Combining diagnostic specimens into pools has been considered as a strategy to augment throughput, decrease turnaround time, and leverage resources. This study utilized a multi-parametric approach to assess optimum pool size, impact of automation, and effect of nucleic acid amplification chemistries on the detection of SARS-CoV-2 RNA in pooled samples for surveillance testing on the Hologic Panther Fusion® System. Dorfman pooled testing was conducted with previously tested SARS-CoV-2 nasopharyngeal samples using Hologic's Aptima® and Panther Fusion® SARS-CoV-2 Emergency Use Authorization assays. A manual workflow was used to generate pool sizes of 5:1 (five samples: one positive, four negative) and 10:1. An automated workflow was used to generate pool sizes of 3:1, 4:1, 5:1, 8:1 and 10:1. The impact of pool size, pooling method, and assay chemistry on sensitivity, specificity, and lower limit of detection (LLOD) was evaluated. Both the Hologic Aptima® and Panther Fusion® SARS-CoV-2 assays demonstrated >85% positive percent agreement between neat testing and pool sizes ≤5:1, satisfying FDA recommendation. Discordant results between neat and pooled testing were more frequent for positive samples with CT>35. Fusion® CT (cycle threshold) values for pooled samples increased as expected for pool sizes of 5:1 (CT increase of 1.92-2.41) and 10:1 (CT increase of 3.03-3.29). The Fusion® assay demonstrated lower LLOD than the Aptima® assay for pooled testing (956 vs 1503 cp/mL, pool size of 5:1). Lowering the cut-off threshold of the Aptima® assay from 560 kRLU (manufacturer's setting) to 350 kRLU improved the assay sensitivity to that of the Fusion® assay for pooled testing. Both Hologic's SARS-CoV-2 assays met the FDA recommended guidelines for percent positive agreement (>85%) for pool sizes ≤5:1. Automated pooling increased test throughput and enabled automated sample tracking while requiring less labor. The Fusion® SARS-CoV-2 assay, which demonstrated a lower LLOD, may be more appropriate for surveillance testing.

Decomposition of acetone by hydrogen peroxide/ozone process in a rotating packed contactor.

The direct use of ozone (O3) in water and wastewater treatment processes is found to be inefficient, incomplete, and limited by the ozone transfer between the gas-liquid interface because of its low solubility and instability in aqueous solutions. Therefore, rotating packed contactors were introduced to improve the transfer of ozone from the gaseous phase to the solution phase, and the effect of several reaction parameters were investigated on the temporal variations of acetone concentration in aqueous solution. The decomposition rate constant of acetone was enhanced by increasing the rotor speed from 450 to 1800 rpm. Increasing the hydrogen peroxide (H2O2)/O3 molar ratios accelerated the decomposition rate until a certain optimum H2O2/O3 molar ratio was reached; further addition of H2O2 inhibited the decomposition of acetone, possibly because excessive amounts of H2O2 added might serve as a scavenger to deplete hydroxyl free radicals.