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1.
Opt Lett ; 48(3): 799-802, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36723592

RESUMO

We demonstrate the first multi-segmented Nd:YLF laser, to the best of our knowledge. The multi-segmented crystal was designed to straightforwardly aim for the minimum thermal stress without sacrificing the overall laser efficiency, with the influence of the pump beam waist position considered in particular. Integrating the enhanced thermo-mechanical resistance of multi-segmented crystal and the alleviated heat load of low quantum defect pumping, this end-pumped 1314 nm Nd:YLF laser system delivered a maximum continuous-wave output power of up to 35.5 W under a pump power of 105 W, corresponding to an optical-to-optical efficiency of 33.8%. Furthermore, by incorporating an acousto-optic modulator, an active Q-switching oscillator was accomplished, yielding a maximum average output power of 22.9 W at a pulse repetition frequency (PRF) of 20 kHz and a largest pulse energy of 13.6 mJ at a PRF of 1 kHz.

2.
Sci Total Environ ; 866: 161387, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36621492

RESUMO

A warming climate is one of the most important driving forces of intensified wildfires globally. The unprecedented wildfires broke out in the Australian 'Black Summer' (November 2019-February 2020), which released massive heat, gases, and particles into the atmosphere. The total carbon dioxide (CO2) emissions from wildfires were estimated at ∼963 million tons by using a top-down approach based on direct satellite measurements of CO2 and fire radiative power. The fire emissions have led to an approximately 50-80 folds increase in total CO2 emission in Australia compared with the similar seasons of 2014-2019. The excess CO2 from wildfires has offset almost half of the global anthropogenic CO2 emission reductions due to the Corona Virus Disease 2019 in 2020. When the wildfires were intense in December 2019, they caused a 1.48 watts per square meter additional positive radiative forcing above the monthly average in Australia and the vicinity. Our findings demonstrate that vast ecosystem disturbance in a warming climate can strongly influence the global carbon cycle and hamper our climate goal of reducing CO2.

3.
Int J Immunopathol Pharmacol ; 37: 3946320221149849, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36598755

RESUMO

OBJECTIVE: Airway inflammation is a prominent feature of asthma and may play an important role in disease pathophysiology. Despite the increasing incidence of asthma worldwide, reliable diagnostic biomarkers are lacking and widely lead to asthma misdiagnosis. Neutrophil-lymphocyte ratio (NLR) is a biomarker of systemic inflammation, in addition to NLR-alanine aminotransferase ratio (NAR) and NLR-albumin ratio (NBR). The aim of this study was to evaluate associations of NLR, NAR, and NBR with diagnosis of childhood asthma to determine if they can aid clinical childhood asthma diagnosis. METHODS: This retrospective case-control study included 89 children with asthma and 53 healthy children from the Wuxi Children's Hospital affiliated with Nanjing Medical University. We applied various statistical tests to the dataset: Mann-Whitney U test to compare characteristics of the case and control groups; chi-squared test to compare categorical variables; Kruskal-Wallis test to compare statistical differences of asthma indicators among groups; receiver operating characteristic (ROC) curves to assess the diagnostic value of indices; and Spearman correlation analysis to evaluate relationships between NLR and lactate dehydrogenase, albumin, aspartate transaminase, and alanine transaminase levels. RESULTS: Compared with controls, the asthma case group had significantly higher white blood cell (p < 0.01), neutrophil, lactate dehydrogenase, C-reactive protein, and NLR levels (p < 0.01) and significantly lower lymphocyte (p = 0.001), platelet (p = 0.039), and albumin levels (p = 0.04). We determined optimal cutoff levels for several metrics: 1.723 for NLR, with sensitivity of 0.73 and specificity of 0.906; 0.135 for NAR, with sensitivity of 0.685 and specificity of 0.887; and 0.045 for NBR, with sensitivity of 0.674 and specificity of 0.906. The areas under the curve (AUCs) were 0.824 for NLR, 0.788 for NAR, 0.818 for NBR, and 0.83 for the combination of NLR + NAR + NBR. CONCLUSION: The combination of NLR, NAR, and NBR biomarkers distinguished asthmatic ones suffering from exacerbation of the condition from healthy children. Thus, our results indicate NLR + NAR + NBR could be used as a clinical biomarker for asthma in children.


Assuntos
Asma , Neutrófilos , Humanos , Criança , Estudos Retrospectivos , Estudos de Casos e Controles , Voluntários Saudáveis , Linfócitos , Biomarcadores , Asma/diagnóstico , Inflamação , Albuminas , Lactato Desidrogenases
4.
Anal Chim Acta ; 1241: 340795, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36657872

RESUMO

Direct observation of metabolites in living cells by mass spectrometry offers a bright future for biological studies but also suffers a severe challenge to untargeted peak assignment to tentative metabolite candidates. In this study, we developed a method combining stable isotope tracing and induced electrospray mass spectrometry for living-cells metabolite measurement and identification. By using 13C6-glucose and ammonium chloride-15N as the sole carbon and nitrogen sources for cell culture, Escherichia coli synthesized metabolites with 15N and 13C elements. Tracing the number of carbon and nitrogen atoms could offer a complementary dimension for candidate peak searching. As a result, the identification confidence of metabolites achieved a universal improvement based on carbon/nitrogen labelling and filtration.


Assuntos
Metabolômica , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização por Electrospray/métodos , Metabolômica/métodos , Isótopos de Carbono/química , Carbono , Nitrogênio , Marcação por Isótopo/métodos
5.
Nanoscale ; 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36688447

RESUMO

Revealing multiple biomolecules in the physiopathological environment simultaneously is crucial in biological and biomedical research. Mass spectrometry (MS) features unique technical advantages in multiplexed and label-free analyses. However, owing to comparably low abundance and poor ionization efficiency of target biomolecules, direct MS profiling of these biological species in vitro or in situ remains a challenge. An emerging route to solve this issue is to devise mass tag (MT)-encoded nanointerfaces which specifically convert the abundance or activity of biomolecules into amplified ion signals of mass tags, offering an ideal strategy for synchronous MS assaying and mapping of multiple targets in biofluids, cells and tissues. This review provides a thorough and organized overview of recent advances in MT-encoded nanointerfaces elaborately tailored for several practical applications in multiplexed MS bioanalysis and biomedical research. First, we start with elucidation of the structural characteristics and working principle of MT-encoded nanointerfaces in specific labeling and sensing of multiple biological targets. In addition, we further discuss the application scenarios of MT-encoded nanointerfaces particularly in multiplexed biomarker assays, cell analysis, and tissue imaging. Finally, the current challenges are pointed out and future prospects of these nanointerfaces in MS analysis are forecast.

6.
Curr Atheroscler Rep ; 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36689071

RESUMO

PURPOSE OF REVIEW: The purpose of the study is to explore the evidence linking telomere length with atherosclerotic ischemic disease. RECENT FINDINGS: There has been a recent expansion in strategies for measuring telomere length, including analyzing genome sequence data and capitalizing on genomic loci that associate with telomere length. These, together with more established approaches, have been used to generate a more complete picture of telomere length relationships with ischemic disease. Whereas earlier meta-analyses suggested an association between short leukocyte telomeres and ischemic disease, several recent large population studies now provide particularly compelling data, including an association with cardiovascular mortality. In addition, whether short leukocyte telomeres might be causally related to ischemic disease has been interrogated using Mendelian randomization strategies, which point to shorter leukocyte telomeres as a determining risk factor. Importantly however, the wide, interindividual variability in telomere length still means that a single assessment of leukocyte telomere length in an individual does not reliably report on a biological aging process. In this regard, recent multi-tissue analyses of telomere length dynamics are providing both new mechanistic insights into how telomere length and shortening rates may participate in atherogenesis and risk prediction opportunities. The balance of evidence indicates that short leukocyte telomeres confer a risk for atherosclerotic cardiovascular disease. Moreover, an integrated analysis of telomere lengths in leukocytes and other tissues may provide a window into individualized telomere dynamics, raising new prospects for risk management.

7.
Mol Pharmacol ; 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36669879

RESUMO

A uricosuric drug benzbromarone, widely used for treatment of gout, hyperpolarizes the membrane potential of airway smooth muscle cells, but how it works remains unknown. Here we show a novel role of benzbromarone in activation of large conductance calcium-activated K+ channels. Benzbromarone results in dose-dependent activation of macroscopic BK currents about 1.7 to 14.5 folds with an EC50 of 111 µM and shifts the voltage-dependent channel activation to a more hyperpolarizing direction about 10 to 54 mV in whole-cell patch clamp recordings. In single-channel recordings, benzbromarone decreases single BKα channel closed dwell time and increases the channel open probability. Co-expressing ß1 subunit also enhances BK activation by benzbromarone with an EC50 of 67 µM and a leftward shift of G-V curve about 44 to 138 mV. Site-directed mutagenesis reveals that a motif of three amino acids 329RKK331 in the cytoplasmic linker between S6 and C-terminal RCK gating ring mediates the pharmacological activation of BK channels by benzbromarone. Further ex vivo assay shows that benzbromarone causes reduction of tracheal strip contraction. Taken together, our findings demonstrate that uricosuric benzbromarone activates BK channels through molecular mechanism of action involving the channel RKK motif of S6-RCK linker. Pharmacological activation of BK channel by benzbromarone causes reduction of tracheal strip contraction, holding a repurposing potential for asthma and pulmonary arterial hypertension or BK channelopathies. Significance Statement We describe a novel role of uricosuric agent benzbromarone in BK channel activation and relaxation of airway smooth muscle contraction. In this study, we find that benzbromarone is an activator of the large-conductance Ca2+- and voltage-activated K+ channel (BK channel) that serves numerous cellular functions including control of smooth muscle contraction. Pharmacological activation of BK channel by an FDA approved drug benzbromarone may hold repurposing potential for treatment of asthma and pulmonary arterial hypertension or BK channeopathies.

8.
Opt Express ; 31(1): 265-273, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36606965

RESUMO

We demonstrate an efficient wavelength-selectable output in the attractive deep-red spectral region from an intracavity frequency converted Nd:YLF/KGW Raman laser. Driven by an acousto-optic Q-switched 1314 nm Nd:YLF laser, two first-Stokes waves at 1461 and 1490 nm were generated owing to the bi-axial properties of KGW crystal. By incorporating intracavity sum-frequency generation and second-harmonic generation with an angle-tuned bismuth borate (BIBO) crystal, four discrete deep-red laser emission lines were yielded at the wavelengths of 692, 698, 731, and 745 nm. Under the incident pump power of 50 W and the repetition rate of 4 kHz, the maximum average output powers of 2.4, 2.7, 3.3, and 3.6 W were attained with the pulse durations of 3.4, 3.2, 4.3, and 3.7 ns, respectively, corresponding to the peak powers up to 177, 209, 190, and 245 kW. The results indicate that the Nd:YLF/KGW Raman laser combined with an angle-adjusted BIBO crystal provides a reliable and convenient approach to achieve the selectable multi-wavelength deep-red laser with short pulse duration and high peak power.

9.
J Environ Sci (China) ; 123: 41-53, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36522002

RESUMO

Accurate monitoring of the atmospheric environment and its evolution are important for understanding the sources, chemical mechanisms, and transport processes of air pollution and carbon emissions in China, and for regulatory and control purposes. This study gives an overview of atmospheric environment monitoring technology and equipment in China and summarizes the major achievements obtained in recent years. China has made great progress in the development of atmospheric environment monitoring technology and equipment with decades of effort. The manufacturing level of atmospheric environment monitoring equipment and the quality of products have steadily improved, and a technical & production system that can meet the requirements of routine monitoring activities has been initiated. It is expected that domestic atmospheric environment monitoring technology and equipment will be able to meet future demands for routine monitoring activities in China and provide scientific assistance for addressing air pollution problems.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Monitoramento Ambiental , Poluição do Ar/prevenção & controle , Poluição do Ar/análise , China , Tecnologia , Poluentes Atmosféricos/análise
10.
J Inorg Biochem ; 239: 112048, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36496289

RESUMO

Six new Pd(II), Pt(II) and Ag(I) complexes, (1);{Pd (L1)]2C6H4}2Cl4} (2); Pt(L2)(DMSO)Cl; 3; {PtL5]2C6H4}2·PhCOO-⋅11NO3-; 4; {[Pt(L4)]2C6H4}; the binuclear cyclometalated complex the polymer chain (5); {[PtL5]C6H4}·NO3-}; and the polymeric silver species (6); Zn(L6)2·AgNO3·CHCl3 were synthesized and thoroughly characterized using X-ray diffraction and spectroscopic techniques (L1=(S,S)-1,4-i-PrOx]2C6H4}2Cl4, L2=Di(2,2-bis(4R-isopropyl-4,5-dihydro-oxazol-2-yl)acetonitrile) zinc (II) (BR1);L3= 1,4-bis(4R-benzyl-4,5-dihydro-oxazol-2-yl)benzene (AR2); L4= 1,4-bis(4R-benzyl-4,5-dihydro-oxazol-2-yl)benzene,L5=1,4-bis(4R-benzyl-4,5-dihydro-oxazol-2-yl)-benzene,L6=Di(2,2-bis(4S-isopropyl-4,5-dihydrooxazol-2-yl)acetonitrile) zinc (II). Complexes 1-6 showed cytotoxic effects against human tumour cell lines, including a multidrug-resistant subline. Oxazoline and Pd complex 1 induced apoptosis in A549 cells. DFT calculations were also performed to exhibit the excellent bioactivity of complex 1 against A549, MDA-MB-231, and KB cells. Complex 1, with the best docking score and a stable interaction network within the binding site of the G-quadruplex, could stably interact with the G-quadruplex. Additionally, complex 1 was further used in the animal experiment of human lung adenocarcinoma cells in nude mice. By comparing with the model control group, the tumour volume, relative tumour volume and relative tumour proliferation rate T/C decreased significantly in the cisplatin group and compound 1 (complex 1) group.


Assuntos
Antineoplásicos , Platina , Animais , Camundongos , Humanos , Platina/farmacologia , Platina/química , Simulação de Acoplamento Molecular , Paládio/farmacologia , Paládio/química , Prata/farmacologia , Teoria da Densidade Funcional , Benzeno , Camundongos Nus , Linhagem Celular Tumoral , Antineoplásicos/química , Zinco
11.
Gastroenterol Rep (Oxf) ; 10: goac071, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36457375

RESUMO

Background: Pediatric perianal fistula is a common disorder. It is more difficult to detect the fistula tract and internal opening (IO) in children than in adults. This study aimed to evaluate the clinical diagnostic value of transcutaneous perianal ultrasound for children with perianal fistula. Methods: A retrospective review was conducted by analysing the preoperative transcutaneous perianal ultrasound and intraoperative exploration results of 203 consecutive patients who were <3 years old and diagnosed with perianal fistula. Analyses were conducted to evaluate the accuracy and consistency of utilizing the transcutaneous perianal ultrasound in the diagnosis of the complexity and location of the IO of perianal fistulas. Results: Compared with intraoperative exploration, the preoperative transcutaneous perianal ultrasonography has almost perfect agreement (Kappa = 0.881, P < 0.001) in the diagnosis of fistula tract complexity and IO with a sensitivity of 92% and a specificity of 97%. In addition, both intraoperative exploration and transcutaneous perianal ultrasound diagnosis showed high consistency in the identification of the IO of perianal fistulas (Quadrant I Kappa = 0.831, Quadrant II Kappa = 0.773, Quadrant III Kappa = 0.735, Quadrant IV Kappa = 0.802, all P < 0.01). The IOs were mainly distributed in Quadrants IV and II in both simple and complex fistulas. Conclusions: Transcutaneous perianal ultrasound, as a non-invasive and simple imaging technique, showed high accuracy in the diagnosis and identification of the fistula classification and IO location. It could be considered a first-line diagnostic instrument for evaluating perianal fistulas among children.

12.
Food Res Int ; 162(Pt B): 112151, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36461412

RESUMO

Cannabis sativa L., has gained increasing attention due to its potential applications in various fields. However, the compositions of hemp seeds from different producing regions are quite different, significantly affects resource utilization. This work conducted the regional differentiation of hemp seeds from Dongbei, Guangxi, Inner Mongolia and Shanxi in China based on the headspace solid phase micro-extraction coupled with gas chromatography-mass spectrometry (HS-SPME/GC-MS) and multivariate analysis. Moreover, the chemical composition, amino acid and fatty acid profiles of hemp seeds and antioxidant activities of hemp protein isolate were evaluated from above four producing regions. The results showed that hemp seeds had large amounts of fat (24.30-34.65%) and protein (21.87-23.40%) with ideal amino acid and fatty acid profiles and large amounts of volatiles. More than 300 volatile compounds were detected, and 35 key contributors to the unique aroma were finally identified out of 110 volatile compounds with odor activity values (OAVs), including 14 aldehydes, 2 ketones, 4 alcohols, 2 esters, 1 acid, 3 aromatics, 5 terpenes and 4 other compounds. The content of alcohols in all hemp seeds was highest and 16 unique volatiles only found in hemp seeds from Shanxi. Meanwhile, the VIP scores indicated that acetic acid, hexanal, hexan-1-ol and eucalyptol contributed the most to the difference among groups. According to the results of fuzzy comprehensive evaluation, the hemp seeds from Shanxi seemed to have the better quality. Therefore, multivariate analysis combined with HS-SPME/GC-MS could effectively distinguish hemp seeds from different producing regions, and thus decipher the geographical characteristics of raw materials.


Assuntos
Cannabis , Microextração em Fase Sólida , Cromatografia Gasosa-Espectrometria de Massas , China , Sementes , Aminoácidos , Ácidos Graxos
13.
Int J Infect Dis ; 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36455810

RESUMO

BACKGROUND: Physical frailty is one of the major concerns among aging people living with HIV. A comprehensive meta-analysis exploring the association between physical frailty and negative health outcomes among people living with HIV is lacking. METHODS: We systematically searched six electronic databases including PubMed, Embase, Web of Science, the Cochrane Library and Chinese databases up to April 10, 2022 for studies examining the association between physical frailty and risk of negative health outcomes among people living with HIV. Relative risks (RRs), odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (CIs) were extracted, and meta-analyses were conducted by using a fixed or random-effects model. RESULTS: In total, 10 studies incorporating 7,755 HIV-seropositive patients (mean age 49.4 years) were included in the meta-analysis. Five studies with 3,434 participants reported the effect of physical frailty on falls. Results showed that physical frailty HIV-seropositive individuals demonstrated a higher risk of future falls (pooled RR 3.74, 95% CI 1.42-9.86) compared to robust HIV-seropositive patients. In addition, meta-analysis of five studies (4,321 participants) reporting the frailty-mortality association showed that physical frailty was significantly associated with a higher risk of all-cause mortality (RR 1.70, 95% CI 1.32-2.19) among people living with HIV. CONCLUSIONS: Physical frailty is a significant risk factor for injurious falls and all-cause mortality in people living with HIV, including falls and all-cause mortality, underscoring needs of routine screening and early intervention of physical frailty among people living with HIV.

14.
Biosci Trends ; 16(6): 434-443, 2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36504071

RESUMO

Keeping adherence to the continuous and standardized CD4 follow-up monitoring service is of great significance to the control of disease progression and the reduction of avoidable mortality for HIV-infected patients. As non-communicable diseases (NCDs) have become main causes of deaths for people with HIV (PWH) in the era of combination antiretroviral therapy (cART), how and to what extent does adherence to routine CD4 monitoring differentially impact on AIDS-related versus NCDs-related deaths in low- and middle-income countries (LMIC) remains elucidated. A CD4 test index was developed by dividing the actual number of received CD4 tests by the theoretical number of CD4 tests that should have been performed according to national treatment guidelines during the study period, with an index value of 0.8-1.2 reflecting compliance. From 1989 to 2020, 14,571 adults were diagnosed with HIV infection in Dehong Prefecture of Yunnan province in Southwestern China, 6,683 (45.9%) PWH had died with the all-cause mortality of 550.13 per 10,000 person-years, including 3,250 (48.6%) AIDS-related deaths (267.53 per 10,000 person-years). Among patients on cART, the median CD4 test index was 1.0 (IQR 0.6-1.3), and 35.2% had a CD4 test index less than 0.8. Cox proportional hazards regression analysis indicated that PWH with CD4 test index at 0.8-1.2 were at the lowest risk of both AIDS-related (aHR = 0.06; 95%CI: 0.05-0.07) and NCDs-related (aHR = 0.13; 95%CI: 0.11-0.16)deaths. Adherence to routine CD4 monitoring is critical for reducing both AIDS-related and NCDs-related mortality of PWH. An appropriate (once or twice a year) rather than an unnecessarily higher frequency of routine CD4 testing could be most cost-effective in reducing mortality in LMIC.


Assuntos
Síndrome de Imunodeficiência Adquirida , Infecções por HIV , Adulto , Humanos , Infecções por HIV/tratamento farmacológico , Síndrome de Imunodeficiência Adquirida/tratamento farmacológico , China/epidemiologia , Fatores de Risco , Contagem de Linfócito CD4
15.
Insect Mol Biol ; 2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36482511

RESUMO

Long non-coding RNAs (lncRNAs), a class of transcripts exceeding 200 nucleotides and lacking protein coding potential, have been proven to play important roles in viral infection and host immunity. Bombyx mori nucleopolyhedrovirus (BmNPV) is an important pathogen, which causes the silkworm disease and leads to a huge challenge to the sericultural industry. At present, research on the roles of insect lncRNAs in host-virus interaction are relatively few. In this study, we explored the function of lincRNA_XR209691.3 that was significantly up-regulated in the silkworm fat body upon BmNPV infection. Firstly, the subcellular localization experiment confirmed that lincRNA_XR209691.3 was present in both the nucleus and cytoplasm. Enhancing the expression of lincRNA_XR209691.3 in BmN cells could promote the proliferation of BmNPV, while inhibition of lincRNA_XR209691.3 by RNA interference suppresses the proliferation of BmNPV. Combining RNA pull-down and mass spectrometry, we identified the host and BmNPV proteins that could interact with lincRNA_XR209691.3. Next, by using truncation experiment and RNA immunoprecipitation (RIP) assay, it was found that lincRNA_XR209691.3 could bind to the Actin domain of BmHSP70. Subsequently, overexpression of lncRNA_XR209691.3 in BmN cells promoted the expression of BmHSP70, while knockdown of BmHsp70 suppressed the replication of BmNPV. Based on the above results, it is speculated that lincRNA_XR209691.3 could promote the proliferation of BmNPV through interaction with BmHSP70, possibly by improving the stability of BmHSP70 and thereby enhancing the expression of BmHSP70. Our results shed light on the lncRNA function in insect-pathogen interactions and provide a new clue to elucidate the molecular mechanism of BmNPV infection.

16.
Front Public Health ; 10: 1023797, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36582384

RESUMO

Objective: This study aimed to provide a basis for epidemic prevention and control measures as well as the management of re-positive personnel by analyzing and summarizing the characteristics of re-positive patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta variant infections discharged from a hospital in the Ningxia Hui Autonomous Region in 2021. Methods: This case-control study included a total of 45 patients with Delta variant infections diagnosed in the Fourth People's Hospital of the Ningxia Hui Autonomous Region between October 17 and November 28, 2021. Based on the nucleic acid test results post-discharge, the patients were dichotomized into re-positive and non-re-positive groups. Based on the time of the first re-positive test, the re-positive group was further divided into <7 and ≥7 days groups to compare their clinical characteristics and explore the possible influencing factors of this re-positivity. Results: Of the 45 total patients, 16 were re-positive (re-positivity rate: 35.6%), including four patients who were re-positive after 2 weeks (re-positivity rate: 8.8%). The median time of the first re-positive after discharge was 7 days (IQR: 14-3). The re-positive group was younger than the non-re-positive group (35 vs. 53, P < 0.05), had a higher proportion of patients who were not receiving antiviral therapy (56.2 vs. 17.2%, P < 0.05). The median CT value of nucleic acid in the re-positive group was considerably greater than that at admission (36.7 vs. 22.6 P < 0.05). The findings demonstrated that neutralizing antibody treatment significantly raised the average IgG antibody level in patients, particularly in those who had not received COVID-19 vaccine (P < 0.05). The median lowest nucleic acid CT value of the ≥7 days group during the re-positive period and the immunoglobulin G (IgG) antibody level at discharge were lower than those in the <7 days group (P < 0.05). When compared to the non-positive group, patients in the ≥7 days group had a higher median virus nucleic acid CT value (27.1 vs. 19.2, P < 0.05) and absolute number of lymphocytes at admission (1,360 vs. 952, P < 0.05), and a lower IgG antibody level at discharge (P < 0.05). Conclusions: In conclusion, this study found that: (1) The re-positivity rate of SARS-CoV-2 Delta variant infection in this group was 35.6%, while the re-positivity rate was the same as that of the original strain 2 weeks after discharge (8.0%). (2) Young people, patients who did not use antiviral therapy or had low IgG antibody levels at discharge were more likely to have re-positive. And the CT value of nucleic acid at the time of initial infection was higher in re-positive group. We speculated that the higher the CT value of nucleic acid at the time of initial infection, the longer the intermittent shedding time of the virus. (3) Re-positive patients were asymptomatic. The median CT value of nucleic acid was > 35 at the re-positive time, and the close contacts were not detected as positive. The overall transmission risk of re-positive patients is low.


Assuntos
COVID-19 , Ácidos Nucleicos , Humanos , Adolescente , SARS-CoV-2/genética , Estudos de Casos e Controles , Assistência ao Convalescente , Vacinas contra COVID-19 , Alta do Paciente , Antivirais , Imunoglobulina G
17.
Sci Total Environ ; 859(Pt 1): 159997, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36368395

RESUMO

Anthropogenic volatile organic compounds (VOCs) are serious pollutants in the atmosphere because of their toxicity and as precursors of secondary organic aerosols and ozone pollution. Although in-situ measurements provide accurate information on VOCs, their spatial coverage is limited and insufficient. In this study, we provide a global perspective for identifying anthropogenic VOC emission sources through the ratio of glyoxal to formaldehyde (RGF) based on satellite observations. We assessed typical cities and polluted areas in the mid latitudes and found that some Asian cities had higher anthropogenic VOC emissions than cities in Europe and America. For heavily polluted areas, such as the Yangtze River Delta (YRD), the areas dominated by anthropogenic VOCs accounted for 23 % of the total study areas. During the COVID-19 pandemic, a significant decline in RGF values was observed in the YRD and western United States, corresponding to a reduction in anthropogenic VOC emissions. Furthermore, developing countries appeared to have higher anthropogenic VOC emissions than developed countries. These observations could contribute to optimising industrial structures and setting stricter pollution standards to reduce anthropogenic VOCs in developing countries.

18.
Mol Ther ; 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36384875

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is a malignant tumor with poor prognosis. Gemcitabine-based chemotherapy has become one of the main modalities of its management. However, gemcitabine resistance frequently occurs, leading to failure of PDAC therapy. Platelet-derived growth factors (PDGFs) and their receptors play important roles in cancer progression and chemoresistance. We aimed to investigate the biological function and therapeutic significance of platelet-derived growth factor C (PDGFC) in drug-resistant PDAC. Our study showed that PDGFC was abnormally highly expressed in gemcitabine-resistant PDAC. Silencing PDGFC expression can enhance the therapeutic effect of gemcitabine on PDAC. Mechanistically, the transcription of PDGFC is mediated by H3K27 acetylation, and PDGFC promotes gemcitabine resistance by activating the PDGFR-PI3K-AKT signaling pathway. The PDGFR inhibitor imatinib inhibits the PDGFR pathway. Imatinib and gemcitabine have a synergistic effect on the treatment of PDAC, and imatinib can significantly enhance the anti-tumor effect of gemcitabine in a drug-resistant PDAC patient-derived xenograft model. In conclusion, PDGFC is a potential predictor of gemcitabine-resistant PDAC. Imatinib inhibits PDGFR activation to promote gemcitabine sensitivity in PDAC. Combined modality regimen of imatinib and gemcitabine is likely to translate into clinical trial for the treatment of PDGFC-associated gemcitabine-resistant patients.

19.
Front Cardiovasc Med ; 9: 988820, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386299

RESUMO

Background: There are few reports published on the comparison of the resting full-cycle ratio (RFR) and fractional flow reserve (FFR) on the assessment of the severity of coronary stenosis. We aimed to investigate the diagnostic accuracy of RFR for detection of functionally significant coronary lesions. Methods: This was an observational, retrospective, single-center study. We evaluated both RFR and FFR for 277 coronary lesions of 235 patients who underwent coronary angiography. Patients presenting with chronic coronary syndrome, unstable angina, or non-ST-elevation myocardial infarction were included. Results: The mean FFR and RFR values were 0.84 ± 0.08 and 0.90 ± 0.08, respectively. RFR significantly correlated with FFR (r = 0.727, P < 0.001). The agreement rate between the FFR and RFR was 79.8% (221/277). The diagnostic performance of RFR vs. FFR was accuracy 79.8%, sensitivity 70.4%, specificity 83.7%, positive predictive value 64.0%, and negative predictive value 87.2%. The discriminative power of RFR to identify lesions with FFR ≤ 0.80 was acceptable when the RFR value was within the gray zone [0.86 ≤ RFR ≤ 0.93; AUC: 0.72 (95% CI:0.63-0.81)], while it was excellent when the RFR value was out of the gray zone [RFR > 0.93 or < 0.86; AUC: 0.94 (95% CI:0.88-0.99)]. Conclusion: RFR was significantly correlated with FFR in the assessment of intermediate coronary stenosis. An RFR-FFR hybrid approach increases the diagnostic accuracy of RFR in the detection of functionally significant lesions.

20.
Chemphyschem ; 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36380531

RESUMO

We report on bimetallic FeRh clusters with a narrow size-distribution grown on graphene on Ir(111) as a carbon-supported model catalyst to promote low-temperature catalytic CO oxidation. By combining scanning tunneling microscopy with catalytic performance measurements, we reveal that Fe-Rh interfaces are active sites for oxygen activation and CO oxidation, especially at low temperatures. Rh core Fe shell clusters not only provide the active sites for the reaction, but also thermally stabilize surface Fe atoms towards coarsening compared with pure Fe clusters. Alternate isotope-labelled CO/O2 pulse experiments show opposite trends on preferential oxidation (PROX) performance as a result of surface hydroxyl species formation and competitive adsorption between CO and O2 . The present results introduce a general strategy to stabilize metallic clusters and to reveal the reaction mechanisms on bimetallic structures for low-temperature catalytic CO oxidation as well as preferential oxidation.

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