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•Successfully doped V into TaON lattice to enhance its photocatalytic activity.•V dopant enhanced e−/h+ separation and prolonged the lifetime of the generated e− and h+.•The VTaON ...converted CO2 into CH4 and CO even under visible light.•The optimal V doping ratio enhancing photocatalytic activity of TaON was 1.5 wt%.
We successfully used V as dopant to enhance activity of TaON for visible light photocatalytic reduction of CO2 into valuable fuels. We investigated that the used V dopants existed in the TaON lattice and replaced several Ta elements in the lattice leading to decrease in the conduction band minimum and increase in the valence band maximum of the prepared VTaON. Hence, the band gap energy of the prepared VTaON was lower than that of prepared TaON or the prepared VTaON material could absorb significant amount of incident visible light for production of e− and h+ pairs, which participated in reactions with CO2 and H2O to generate CH4, CO, O2 and H2. We also investigated that the optimal V/Ta ratio (or optimal amount of V dopant) for maximum enhancing photocatalytic activity of TaON was 1.5 wt%. The prepared 1.5VTaON visible light photocatalytically converted CO2 with H2O to generate CH4, CO, O2 and H2 with generation rates of 673, 206, 1479 and 67 (µmol·g−1cat·h−1), respectively.
Abstract
Background
Little is known about the natural history of asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.
Methods
We conducted a prospective study at a ...quarantine center for coronavirus disease 2019 in Ho Chi Minh City, Vietnam. We enrolled quarantined people with reverse-transcription polymerase chain reaction (RT-PCR)–confirmed SARS-CoV-2 infection, collecting clinical data, travel and contact history, and saliva at enrollment and daily nasopharyngeal/throat swabs (NTSs) for RT-PCR testing. We compared the natural history and transmission potential of asymptomatic and symptomatic individuals.
Results
Between 10 March and 4 April 2020, 14 000 quarantined people were tested for SARS-CoV-2; 49 were positive. Of these, 30 participated in the study: 13 (43%) never had symptoms and 17 (57%) were symptomatic. Seventeen (57%) participants imported cases. Compared with symptomatic individuals, asymptomatic people were less likely to have detectable SARS-CoV-2 in NTS collected at enrollment (8/13 62% vs 17/17 100%; P = .02). SARS-CoV-2 RNA was detected in 20 of 27 (74%) available saliva samples (7 of 11 64% in the asymptomatic group and 13 of 16 81% in the symptomatic group; P = .56). Analysis of RT-PCR positivity probability showed that asymptomatic participants had faster viral clearance than symptomatic participants (P < .001 for difference over the first 19 days). This difference was most pronounced during the first week of follow-up. Two of the asymptomatic individuals appeared to transmit SARS-CoV-2 to 4 contacts.
Conclusions
Asymptomatic SARS-CoV-2 infection is common and can be detected by analysis of saliva or NTSs. The NTS viral loads fall faster in asymptomatic individuals, but these individuals appear able to transmit the virus to others.
Forty-three percent (13/30) of confirmed SARS-CoV-2–infected individuals were asymptomatic, with the virus detected in both saliva and nasopharyngeal/throat swabs. Viral clearance was faster in asymptomatic individuals, but they still appeared able to pass the infection to others.
Talaromyces marneffei
is a dimorphic fungus that causes substantial disease in Asia, especially among persons infected with the human immunodeficiency virus. In this randomized, controlled trial, ...initial therapy with amphotericin B was found to be superior to itraconazole.
The dimorphic fungus
Talaromyces
(previously
Penicillium
)
marneffei
causes a life-threatening mycosis in immunocompromised persons living in or traveling to Southeast Asia, China, and India.
1
Talaromycosis (previously penicilliosis) is a major cause of human immunodeficiency virus (HIV)–related death; its prevalence is surpassed only by the prevalence of tuberculosis and cryptococcosis,
2
and it leads to 4 to 15% of HIV-related hospital admissions in regions in which the disease is endemic.
3
–
7
Talaromycosis is increasingly diagnosed among patients who are not infected with HIV but who have other immunodeficiency conditions
8
and is reported to be the second most common cause of all . . .
Herein, Cu was incorporated into ZnO lattice to reduce its band gap as well as to extend its visible radiation response. The obtained Cu-ZnO was continuously integrated with g-C3N4 to create ...Cu-ZnO/g-C3N4Z-direct scheme photocatalyst for advanced atrazine removal. Radical scavenging experiments have been also conducted to clearly figure out photocatalytic mechanism for degradation of atrazine by the synthesized photocatalyst. The synthesized Cu-ZnO only utilized the generated h+ for atrazine degradation (direct and indirect via formation hydroxyl radicals (•OH)) and the g-C3N4 only utilized the generated e− for atrazine degradation (indirect via reaction with O2 to form superoxide anion, which needed to continuously react with H2O to form •OH). Therefore, the photocatalytic atrazine degradation by synthesized Cu-ZnO material was greater than that by synthesized g-C3N4 material. Cu-ZnO/g-C3N4 utilized both generated e− and h+ for degradation of atrazine. Thus, the photocatalytic atrazine degradation by the synthesized Cu-ZnO/g-C3N4 was greater than those of single g-C3N4 or Cu-ZnO materials. Finally, the conducted recycling experiments indicated great stability of synthesized Cu-ZnO/g-C3N4 during long-term atrazine degradation process opening new era for application of the material in practical systems.
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•Cu doped into ZnO lattice to reduce its band gap and to extend its visible radiation response.•Cu-ZnO was successfully combined with g-C3N4 to establish Z direct scheme system.•Z-scheme prevented fast recombination of e− and h+ and maintained their re-dox potential.•The Cu-ZnO/g-C3N4 utilized both generated e− and h+ for degradation of atrazine.•The Cu-ZnO/g-C3N4 showed excellent activity and stability during long-term photocatalysis.
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In this study, we firstly aimed to use Nb as dopant to dope into the TiO2 lattice in order to narrow band gap energy or enhance photocatalytic activity of the Nb-TiO2. Then, the ...prepared Nb-TiO2 was combined with g-C3N4 to establish Nb-TiO2/g-C3N4 direct Z-scheme system for superior reduction of CO2 into valuable fuels even under visible light. The obtained results indicated that the band gap energy of the Nb-TiO2 (2.91 eV) was lower than that of the TiO2 (3.2 eV). In the successfully established Nb-TiO2/g-C3N4 direct Z-scheme system, the photo-excited e− in the CB of the Nb-TiO2 combined with the photo-excited h+ in the VB of the g-C3N4 preserving the existence of e− in the CB of the g-C3N4 and h+ in the VB of Nb-TiO2, and thereby, the system produced numerous amount of available e−/h+ pairs for the reduction of CO2 into various valuable fuels. In addition, the produced e− of the Nb-TiO2/g-C3N4 existing in the CB of the g-C3N4, which the potential energy is approximately −1.2 V, would be strong enough for the reduction of CO2 to generate not only CH4 and CO but also HCOOH. Among established Nb-TiO2/g-C3N4 materials, the 50Nb-TiO2/50 g-C3N4 material was the best material for the CO2 reduction.
Mpox was diagnosed in 2 women returning to Vietnam from the United Arab Emirates. The monkeypox viruses belonged to an emerging sublineage, A.2.1, distinct from B.1, which is responsible for the ...ongoing multicountry outbreak. Women could contribute to mpox transmission, and enhanced genomic surveillance is needed to clarify pathogen evolution.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Targeted therapy with tyrosine kinase inhibitors (TKI) provides survival benefits to a majority of patients with non-small cell lung cancer (NSCLC). However, resistance to TKI almost always develops ...after treatment. Although genetic and epigenetic alterations have each been shown to drive resistance to TKI in cell line models, clinical evidence for their contribution in the acquisition of resistance remains limited. Here, we employed liquid biopsy for simultaneous analysis of genetic and epigenetic changes in 122 Vietnamese NSCLC patients undergoing TKI therapy and displaying acquired resistance. We detected multiple profiles of resistance mutations in 51 patients (41.8%). Of those, genetic alterations in EGFR, particularly EGFR amplification (n = 6), showed pronounced genome instability and genome-wide hypomethylation. Interestingly, the level of hypomethylation was associated with the duration of response to TKI treatment. We also detected hypermethylation in regulatory regions of Homeobox genes which are known to be involved in tumor differentiation. In contrast, such changes were not observed in cases with MET (n = 4) and HER2 (n = 4) amplification. Thus, our study showed that liquid biopsy could provide important insights into the heterogeneity of TKI resistance mechanisms in NSCLC patients, providing essential information for prediction of resistance and selection of subsequent treatment.
The X-linked hyper IgM syndrome is a primary immunodeficiency disorder (PID) due to mutations in the
CD40LG
gene. Hyper IgM syndrome is characterized by the absence or decreased levels of IgG and IgA ...and normal or elevated IgM levels in serum. Affected patients become susceptible to infections such as pneumonia, diarrhea, and skin ulcer types. Hematopoietic stem cell transplantation is the only treatment currently available and ideally performed before the age of 10 years. Early, accurate diagnosis will contribute to the effective treatment for patients with hyper IgM. The patients from different Vietnamese families who have been diagnosed with hyper IgM at The Allergy, Immunology and Rheumatology Department, Vietnam National Hospital Pediatrics, were performed a genetic analysis using whole exome sequencing. The mutations were confirmed by the Sanger sequencing method in patients and their families. The influence of the mutations was predicted with the in silico analysis tools: PROVEAN, SIFT, PolyPhen-2, and MutationTaster. In this study, two novel mutations (p.Thr254fs and p.Leu138Phe) in the
CD40LG
gene were found in Vietnamese patients with X-linked hyper IgM syndrome. Our results contribute to the general understanding of the etiology of the disease and can help diagnose the different forms of PID.
In the study, we doped N into TiO2 lattice to narrow its band gap energy. Then, the synthesized N doped TiO2 material was combined with AgI to form AgI/N–TiO2 (ANT) direct Z scheme materials. The ...synthesized materials were utilized for photocatalytic removal of tetracycline (TC) using visible irradiation as an excitation source. We also conducted radical scavenging experiments to determine photocatalytic degradation mechanism. We investigated that these photo-excited electrons (e−) in N–TiO2 conduction band tended to combine with the left holes (h+) in AgI valence band maintaining h+ in the valence band of the N–TiO2 and e− in the conduction band of the AgI. The remained e− and h+ have high redox potential to initiate for photocatalytic decomposition of TC. Thus, the TC degradation by the ANT materials were significant greater than those by single components (AgI or N–TiO2). We also investigated that the TC degradation by the ANT-30 material, which the AgI: N–TiO2 molar ratio was 30%, exhibited that highest degradation efficiency. Finally, the ANT photocatalyst exhibited excellent stability during TC degradation processes supporting for its promising potential application in practical systems.
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•Synthesized Ta3N5 and V–Ta3N5 successfully converted CO2 to valuable fuels.•V dopant enhanced electron–hole separation and prolonged its lifetime.•V–Ta3N5 exhibited great increases ...in light adsorption and decreases in band gap energy.•V–Ta3N5 reduced CO2 and H2O vapor to CH4, CO, O2, and H2 even under visible light.•A V/Ta ratio of 2wt.% was optimal for enhancing the photocatalytic activity of Ta3N5.
In this study, Ta3N5 and V-doped Ta3N5 (V–Ta3N5) were synthesized as catalysts for the conversion of CO2 into valuable fuels under visible light. As compared with Ta2O5, the synthesized Ta3N5 and V–Ta3N5 exhibited great increases in visible light adsorption and decreases in band gap energy. Therefore, the synthesized Ta3N5 and V–Ta3N5 photocatalytically converted CO2 into CO and CH4 even under visible light. The V dopants, which existed in the Ta3N5 lattice, could act as an intermediate band (V3d) between the valence band (N2p) and the conduction band (Ta5d) of the Ta3N5 to increase the electron–hole separation efficiency of the photocatalyst. Thus, the photocatalytic activity of V–Ta3N5 was much higher than that of Ta3N5. However, an increase in the V doping ratio led the formation of VN particles distributed on the Ta3N5 surface. The formed particles eclipsed the light reaching the photocatalyst surface, resulted in a decrease in photocatalytic activity. The optimal V doping ratio in V–Ta3N5 was found to be 2wt.%. As a result, the production rates of CH4, CO, O2, and H2 generated from the photocatalytic reduction of CO2 by 2wt.% V–Ta3N5 under visible light were 425, 236, 1003, and 56µmolg−1cath−1, respectively.
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