Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 65
Filtrar
1.
Chin J Physiol ; 66(5): 313-325, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37929342

RESUMO

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.


Assuntos
Hemerocallis , Extratos Vegetais , Qualidade do Sono , Humanos , Flores/química , Hemerocallis/química , Interleucina-6 , Macrófagos , Óxido Nítrico , Extratos Vegetais/farmacologia
2.
Epidemiology ; 33(6): 797-807, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35944149

RESUMO

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.


Assuntos
COVID-19 , Surtos de Doenças , Militares , COVID-19/epidemiologia , COVID-19/prevenção & controle , Surtos de Doenças/prevenção & controle , Feminino , Humanos , Masculino , Militares/estatística & dados numéricos , Filogenia , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Estados Unidos/epidemiologia
3.
Anal Chem ; 91(15): 9424-9429, 2019 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-31313917

RESUMO

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.


Assuntos
Anticorpos Imobilizados/imunologia , Imunoensaio/métodos , Orientação Espacial , Peptídeos/química , Anticorpos de Domínio Único/imunologia , Imunoensaio/normas , Limite de Detecção , Microesferas , Multimerização Proteica , Proteínas não Estruturais Virais/sangue
4.
J Nanosci Nanotechnol ; 18(3): 2241-2248, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448754

RESUMO

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.

6.
J Nanosci Nanotechnol ; 15(4): 2850-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26353504

RESUMO

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.


Assuntos
Óxido Ferroso-Férrico/química , Fosfatos/química , Poliaminas/química , Adsorção , Fosfatos/isolamento & purificação , Dióxido de Silício/química , Termodinâmica , Água
7.
J Nanosci Nanotechnol ; 13(4): 2974-80, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23763188

RESUMO

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.

8.
Microbiol Spectr ; 11(1): e0228622, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36519888

RESUMO

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.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , SARS-CoV-2/genética , Mutação , Saúde Pública
9.
World J Clin Cases ; 11(7): 1498-1505, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36926405

RESUMO

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.

10.
BJS Open ; 7(1)2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36849753

RESUMO

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).


Assuntos
Carcinoma Hepatocelular , Laparoscopia , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/cirurgia , Hepatectomia , Recidiva Local de Neoplasia/epidemiologia , Qualidade de Vida , Neoplasias Hepáticas/cirurgia , Ásia/epidemiologia , Laparoscopia/efeitos adversos
11.
Environ Technol ; 43(6): 805-814, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32741260

RESUMO

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.


Assuntos
Cobre , Poluentes Químicos da Água , Adsorção , Íons , Cinética , Fenômenos Magnéticos , Polímeros , Dióxido de Silício , Poluentes Químicos da Água/análise
12.
Chem Phys Lipids ; 244: 105191, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35257749

RESUMO

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.


Assuntos
Curcumina , Lipossomos , Disponibilidade Biológica , Curcumina/química , Sistemas de Liberação de Medicamentos , Lipossomos/química , Tamanho da Partícula
13.
Mil Med ; 187(7-8): 802-807, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33861353

RESUMO

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.


Assuntos
Leptospira , Leptospirose , Militares , Infecções por Rickettsia , Tifo por Ácaros , Tifo Endêmico Transmitido por Pulgas , Animais , Anticorpos Antibacterianos , Honduras/epidemiologia , Humanos , Imunoglobulina G , Leptospirose/epidemiologia , Camundongos , Infecções por Rickettsia/epidemiologia , Infecções por Rickettsia/microbiologia
14.
Process Saf Environ Prot ; 167: 695-707, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36185493

RESUMO

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.

15.
Mil Med ; 187(5-6): e655-e660, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33428750

RESUMO

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.


Assuntos
Dengue , Anticorpos Antivirais , Dengue/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Técnicas de Amplificação de Ácido Nucleico , Sensibilidade e Especificidade
16.
AJPM Focus ; 1(1): 100003, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36896336

RESUMO

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.

17.
Microorganisms ; 10(5)2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35630476

RESUMO

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.

18.
PLoS One ; 17(11): e0276729, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36342921

RESUMO

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.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , RNA Viral/genética , COVID-19/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Automação , Sensibilidade e Especificidade
19.
Water Environ Res ; 83(7): 588-93, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21790076

RESUMO

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.


Assuntos
Acetona/química , Peróxido de Hidrogênio/química , Ozônio/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Água/química , Oxirredução , Purificação da Água/instrumentação
20.
Environ Technol ; 33(15-16): 1799-806, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22439567

RESUMO

Platinum-incorporated TiO2 (Pt-TiO2) and silver-incorporated TiO2 (Ag-TiO2) coatings on sapphire tubes of a thin-film photoreactor were prepared using a photoreduction process. Results of X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) revealed that the Ag-TiO2 coatings consisted of a mixture of Ag2O, Ag and TiO2 particles, owing to the partial oxidization of silver particles on the TiO2 coatings, while the Pt-TiO2 coating contained a mixture of Pt and TiO2 particles. Diffuse reflectance UV-Vis spectra (DRS) showed that metal particles (Ag or Pt) incorporated into the TiO2 coatings promoted optical absorption in the visible region and made it possible for the coatings to be excited by visible light. Photoluminescence (PL) spectra showed that the PL intensity of the Pt-TiO2 coating was lower than that of the Ag-TiO2 and TiO2 coatings, indicating that the Pt-TiO2 coating had a higher efficiency of charge carrier trapping, immigration and transfer, which subsequently promoted the pseudo-first-order rate constants after the UV/TiO2 process. The Pt-TiO2 coatings for the photocatalytic decomposition of o-cresol under UV light irradiation corresponded to a higher pseudo-first-order rate constant (k) of 0.02 min(-1) when compared with the photocatalytic decomposition rates of pure TiO2 coatings (k = 0.0062 min(-1)) and Ag-TiO2 coatings (k = 0.01 min(-1)). The experimental results also indicated that the photodegradation rate of the Pt-TiO2 coating under visible light irradiation was significantly higher than the photodegradation rates of the Ag-TiO2 and pure TiO2 coatings.


Assuntos
Cresóis/química , Poluentes Ambientais/química , Fotólise , Titânio/química , Platina/química , Prata/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA