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1.
Sci Rep ; 14(1): 10149, 2024 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-38698048

RESUMO

This study aims to investigate the potential impact of high-dose radiotherapy (RT) on brain structure, cognitive impairment, and the psychological status of patients undergoing brain tumor treatment. We recruited and grouped 144 RT-treated patients with brain tumors into the Low dose group (N = 72) and the High dose group (N = 72) according to the RT dose applied. Patient data were collected by using the HADS and QLQ-BN20 system for subsequent analysis and comparison. Our analysis showed no significant correlation between the RT doses and the clinicopathological characteristics. We found that a high dose of RT could aggravate cognitive impairment and deteriorate patient role functioning, indicated by a higher MMSE and worsened role functioning in the High dose group. However, the depression status, social functioning, and global health status were comparable between the High dose group and the Low dose group at Month 0 and Month 1, while being worsened in the High dose group at Month 3, indicating the potential long-term deterioration of depression status in brain tumor patients induced by high-dose RT. By comparing patient data at Month 0, Month 1, Month 3, Month 6, and Month 9 after RT, we found that during RT treatment, RT at a high dose could aggravate cognitive impairment in the short term and lead to worsened patient role functioning, and even deteriorate the overall psychological health status of patients in the long term.


Assuntos
Neoplasias Encefálicas , Disfunção Cognitiva , Humanos , Masculino , Feminino , Disfunção Cognitiva/etiologia , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/psicologia , Pessoa de Meia-Idade , Idoso , Encéfalo/efeitos da radiação , Encéfalo/patologia , Adulto , Dosagem Radioterapêutica , Depressão/etiologia , Qualidade de Vida
2.
Plant Commun ; : 100934, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689493

RESUMO

In angiosperms, the pollen tube enters the receptive synergid cell, where they rupture to release its cytoplasm along with two sperm cells. Although this interaction is complex, the exact signal transducers that trigger the bursting of pollen tubes are not well understood. In this study, we identify three homologous Receptor-Like Cytoplasmic Kinase (RLCK) expressed in pollen tubes, named Delayed Burst 1/2/3 (DEB1/2/3) in Arabidopsis, which play a crucial role in this process. These genes produce proteins localized on the plasma membrane, and knockout of them causes delayed pollen tube burst and the entrance of additional pollen tubes into the embryo sac due to fertilization recovery. We show that DEBs interact with the Ca2+ pump ACA9, influencing the dynamics of cytoplasmic Ca2+ in pollen tubes through phosphorylation. These results highlight the importance of DEBs as key signal transducers and the critical function of the DEB-ACA9 axis in the timely pollen tube burst in synergids.

3.
Antiviral Res ; : 105905, 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38740191

RESUMO

The rapid emergence of Severe Acute Respiratory Syndrome Coronavirus type 2 (SARS-CoV-2) variants, coupled with severe immune evasion and imprinting, has jeopardized the vaccine efficacy, necessitating urgent development of broad protective vaccines. Here, we propose a strategy employing recombinant rabies viruses (RABV) to create a universal SARS-CoV-2 vaccine expressing heterologous tandem receptor-binding domain (RBD) trimer from the SARS-CoV-2 Prototype, Delta, and Omicron strains (SRV-PDO). The results of mouse immunization indicated that SRV-PDO effectively induced cellular and humoral immune responses, and demonstrated higher immunogenicity and broader SARS-CoV-2 neutralization compared to the recombinant RABVs that only expressed RBD monomers. Moreover, SRV-PDO exhibited full protection against SARS-CoV-2 in the challenge assay. This study demonstrates that recombinant RABV expressing tandem RBD-heterotrimer as a multivalent immunogen could elicit a broad-spectrum immune response and potent protection against SARS-CoV-2, making it a promising candidate for future human or veterinary vaccines and offering a novel perspective in other vaccine design.

4.
Opt Express ; 32(6): 8723-8735, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571123

RESUMO

In this study, a Si defect structure was added into the silica network in order to activate the bismuth and silica structure active center. TD-DFT theoretical simulations show that the Bi and Si ODC(I) models can excite the active center of the E-band at 1408 nm. Additionally, the Bi-doped silica fiber (BDSF) with improved fluorescence was fabricated using atomic layer deposition (ALD) combined with the modified chemical vapor deposition (MCVD) technique. Some tests were used to investigate the structural and optical properties of BDSF. The UV-VIS spectral peak of the BDSF preform is 424 cm-1, and the binding energy of XPS is 439.3 eV, indicating the presence of Bi° atom in BDSF. The Raman peak near 811 cm-1 corresponds to the Bi-O bond. The Si POL defect lacks a Bi-O structure, and the reason for the absence of simulated active center from the E-band is explained. A fluorescence spectrometer was used to analyze the emission peak of a BDSF at 1420 nm. The gain of the BDSF based optical amplifier was measured 28.8 dB at 1420 nm and confirmed the effective stimulation of the bismuth active center in the E-band.

5.
Opt Express ; 32(6): 8937-8949, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571139

RESUMO

In this study, PbS/Er co-doped fibers (PEDFs) were fabricated by atomic layer deposition (ALD) combined with modified chemical vapor deposition (MCVD). A pumping scheme based on two-photon absorption at 1310 nm of PEDF is proposed for L + band amplification. Through the theoretical analysis, the local environment of Er3+ is changed due to the co-doping of PbS, which improves the two-photon absorption efficiency near 1300 nm. Compared with the 980 nm pump, the PEDFs excited by the 1310 nm pump show better amplification performance in the L + band. And in a bi-directional pumping system, PEDF achieves over 22 dB of gain in the whole L band. In particular, the bandwidth of over 20 dB gain was extended to 1627 nm with a noise figure as low as 4.9 dB. To the best of our knowledge, this is the first time that a high-gain bandwidth of L band amplification has been extended to 1627 nm. The results of unsaturated loss also show that PbS co-doping improves the two-photon absorption efficiency of PEDF to broaden the amplification bandwidth of L + band. These results demonstrate that an effective L + band amplification method is practically provided for future ultra-wideband optical communications.

6.
Materials (Basel) ; 17(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38673091

RESUMO

This paper describes the effects of macro fibers on permeability and crack surface topography of layered fiber-reinforced concrete (FRC) specimens with different layering ratios under uniaxial tensile load. The crack permeability of layered FRC specimens is investigated by a self-designed permeability setup. The topographical analysis of crack surfaces is investigated by a custom-designed laser scanning setup. The results show that when the fiber volume content and layering ratio of the FRC layer are constant, the tensile toughness of layered FRC specimens depends on the proportion of steel fiber in macro fibers, and with an increase in the proportion of steel fiber, the tensile toughness of layered FRC specimens increases. For the layered FRC specimens, the crack permeability is much lower than that of the normal concrete (NC) specimen. A significant positive synergistic effect on crack impermeability can be achieved by the combination of steel fiber and polypropylene fiber in the SF80PP2.3 specimen. The crack surface roughness parameter (Rn) values of the NC layer in layered FRC specimens are all higher than those of the NC specimen, and the crack surface Rn of the FRC layer in layered FRC specimens is higher than that of the unlayered FRC specimens. This can effectively increase the head loss of cracks and reduce the crack permeability of layered FRC specimens.

7.
Materials (Basel) ; 17(8)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38673176

RESUMO

This paper describes hybrid fiber's influence on the crack permeability of cracked concrete exposed to freeze-thaw cycles. A permeability setup and a laser-scanning setup have been designed to measure the crack permeability and the fractured surface roughness of cracked hybrid fiber-reinforced concrete, containing polypropylene fiber and steel fiber, under a splitting tensile load. The results show that, when the effective crack width of the specimens is less than 25 µm, the rough crack surface significantly reduces the concrete's crack permeability. As the crack width increases, the effect of the concrete crack surface on crack permeability gradually decreases, and the crack permeability of the concrete is closer to the Poiseuille flow model. The permeability parameter α derived from the Poiseuille flow model is effective for assessing the crack permeability of concrete. Compared to the modified factor ξ of crack permeability, the permeability parameter α can effectively evaluate and quantify the development trend of crack permeability within a certain range of crack widths. The permeability parameter α of SF20PP2.3, subjected to the same freeze-thaw cycles, decreases by 16.3-94.8% compared to PP4.6 and SF40, and SF20PP2.3 demonstrates a positive synergistic effect on the crack impermeability of cracked concrete. The crack impermeability of SF40PP2.3, subjected to the same freeze-thaw cycles, lies between that of PP6.9 and SF60. The roughness of crack surface (X) and the crack permeability (Y) are highly correlated and follow an exponential curve (Y = 1.0415 × 107·e-6.025·X) in concrete. This demonstrates that hybrid fibers enhance crack impermeability by increasing the crack surface roughness. Furthermore, the combination of polypropylene fiber and steel fiber effectively promotes the formation of micro-cracks and facilitates the propagation of multiple cracks in the concrete matrix. This combination increases the head loss of water flow through the concrete and decreases the crack permeability.

8.
Sci Total Environ ; 925: 171767, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38499102

RESUMO

Soil water conditions are known to influence soil nutrient availability, but the specific impact of different conditions on soil phosphorus (P) availability through the modulation of P-cycling functional microbial communities in hyper-arid desert ecosystems remains largely unexplored. To address this knowledge gap, we conducted a 3-year pot experiment using a typical desert plant species (Alhagi sparsifolia Shap.) subjected to two water supply levels (25 %-35 % and 65 %-75 % of maximum field capacity, MFC) and four P-supply levels (0, 1, 3, and 5 g P m-2 y-1). Our investigation focused on the soil Hedley-P pool and the four major microbial groups involved in the critical phases of soil microbial P-cycling. The results revealed that the drought (25 %-35 % MFC) and no P-supply treatments reduced soil resin-P and NaHCO3-Pi concentrations by 87.03 % and 93.22 %, respectively, compared to the well-watered (65 %-75 % MFC) and high P-supply (5 g P m-2 y-1) treatments. However, the P-supply treatment resulted in a 12 %-22 % decrease in the soil NH4+-N concentration preferred by microbes compared to the no P-supply treatment. Moreover, the abundance of genes engaged in microbial P-cycling (e.g. gcd and phoD) increased under the drought and no P-supply treatments (p < 0.05), suggesting that increased NH4+-N accumulation under these conditions may stimulate P-solubilizing microbes, thereby promoting the microbial community's investment in resources to enhance the P-cycling potential. Furthermore, the communities of Steroidobacter cummioxidans, Mesorhizobium alhagi, Devosia geojensis, and Ensifer sojae, associated with the major P-cycling genes, were enriched in drought and no or low-P soils. Overall, the drought and no or low-P treatments stimulated microbial communities and gene abundances involved in P-cycling. However, this increase was insufficient to maintain soil P-bioavailability. These findings shed light on the responses and feedback of microbial-mediated P-cycling behaviors in desert ecosystems under three-year drought and soil P-deficiency.


Assuntos
Ecossistema , Microbiota , Solo , Secas , Microbiologia do Solo , Plantas
9.
Virol Sin ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38556051

RESUMO

The Ebola virus (EBOV) is a member of the Orthoebolavirus genus, Filoviridae family, which causes severe hemorrhagic diseases in humans and non-human primates (NHPs), with a case fatality rate of up to 90%. The development of countermeasures against EBOV has been hindered by the lack of ideal animal models, as EBOV requires handling in biosafety level (BSL)-4 facilities. Therefore, accessible and convenient animal models are urgently needed to promote prophylactic and therapeutic approaches against EBOV. In this study, a recombinant vesicular stomatitis virus expressing Ebola virus glycoprotein (VSV-EBOV/GP) was constructed and applied as a surrogate virus, establishing a lethal infection in hamsters. Following infection with VSV-EBOV/GP, 3-week-old female Syrian hamsters exhibited disease signs such as weight loss, multi-organ failure, severe uveitis, high viral loads, and developed severe systemic diseases similar to those observed in human EBOV patients. All animals succumbed at 2-3 days post-infection (dpi). Histopathological changes indicated that VSV-EBOV/GP targeted liver cells, suggesting that the tissue tropism of VSV-EBOV/GP was comparable to wild-type EBOV (WT EBOV). Notably, the pathogenicity of the VSV-EBOV/GP was found to be species-specific, age-related, gender-associated, and challenge route-dependent. Subsequently, equine anti-EBOV immunoglobulins and a subunit vaccine were validated using this model. Overall, this surrogate model represents a safe, effective, and economical tool for rapid preclinical evaluation of medical countermeasures against EBOV under BSL-2 conditions, which would accelerate technological advances and breakthroughs in confronting Ebola virus disease.

10.
Antiviral Res ; 225: 105854, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38447647

RESUMO

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with frequent mutations has seriously damaged the effectiveness of the 2019 coronavirus disease (COVID-19) vaccine. There is an urgent need to develop a broad-spectrum vaccine while elucidating the underlying immune mechanisms. Here, we developed a SARS-CoV-2 virus-like particles (VLPs) vaccine based on the Canarypox-virus vector (ALVAC-VLPs) using CRISPR/Cas9. Immunization with ALVAC-VLPs showed the effectively induce SARS-CoV-2 specific T and B cell responses to resist the lethal challenge of mouse adaptive strains. Notably, ALVAC-VLPs conferred protection in golden hamsters against SARS-CoV-2 Wuhan-Hu-1 (wild-type, WT) and variants (Beta, Delta, Omicron BA.1, and BA.2), as evidenced by the prevention of weight loss, reduction in lung and turbinate tissue damage, and decreased viral load. Further investigation into the mechanism of immune response induced by ALVAC-VLPs revealed that toll-like receptor 4 (TLR4) mediates the recruitment of dendritic cells (DCs) to secondary lymphoid organs, thereby initiating follicle assisted T (Tfh) cell differentiation, the proliferation of germinal center (GC) B cells and plasma cell production. These findings demonstrate the immunogenicity and efficacy of the safe ALVAC-VLPs vaccine against SARS-CoV-2 and provide valuable insight into the development of COVID-19 vaccine strategies.


Assuntos
COVID-19 , Vacinas de Partículas Semelhantes a Vírus , Camundongos , Animais , Humanos , SARS-CoV-2 , Vacinas contra COVID-19 , Sistemas CRISPR-Cas , Edição de Genes , Anticorpos Antivirais , Anticorpos Neutralizantes
11.
Glob Chang Biol ; 30(3): e17213, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38436125

RESUMO

Paddy fields serve as significant reservoirs of soil organic carbon (SOC) and their potential for terrestrial carbon (C) sequestration is closely associated with changes in SOC pools. However, there has been a dearth of comprehensive studies quantifying changes in SOC pools following extended periods of rice cultivation across a broad geographical scale. Using 104 rice paddy sampling sites that have been in continuous cultivation since the 1980s across China, we studied the changes in topsoil (0-20 cm) labile organic C (LOC I), semi-labile organic C (LOC II), recalcitrant organic C (ROC), and total SOC. We found a substantial increase in both the content (48%) and density (39%) of total SOC within China's paddy fields between the 1980s to the 2010s. Intriguingly, the rate of increase in content and density of ROC exceeded that of LOC (I and II). Using a structural equation model, we revealed that changes in the content and density of total SOC were mainly driven by corresponding shifts in ROC, which are influenced both directly and indirectly by climatic and soil physicochemical factors; in particular temperature, precipitation, phosphorous (P) and clay content. We also showed that the δ13 CLOC were greater than δ13 CROC , independent of the rice cropping region, and that there was a significant positive correlation between δ13 CSOC and δ13 Cstraw . The δ13 CLOC and δ13 CSOC showed significantly negative correlation with soil total Si, suggesting that soil Si plays a part in the allocation of C into different SOC pools, and its turnover or stabilization. Our study underscores that the global C sequestration of the paddy fields mainly stems from the substantial increase in ROC pool.


Assuntos
Oryza , Solo , Carbono , China , Geografia
12.
Int J Biol Macromol ; 264(Pt 2): 130820, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38484812

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and its variants has resulted in global economic losses and posed a threat to human health. The pandemic highlights the urgent need for an efficient, easily producible, and broad-spectrum vaccine. Here, we present a potentially universal strategy for the rapid and general design of vaccines, focusing on the design and testing of omicron BA.5 RBD-conjugated self-assembling ferritin nanoparticles (NPs). The covalent bonding of RBD-Fc to protein A-ferritin was easily accomplished through incubation, resulting in fully multivalent RBD-conjugated NPs that exhibited high structural uniformity, stability, and efficient assembly. The ferritin nanoparticle vaccine synergistically stimulated the innate immune response, Tfh-GCB-plasma cell-mediated activation of humoral immunity and IFN-γ-driven cellular immunity. This nanoparticle vaccine induced a high level of cross-neutralizing responses and protected golden hamsters challenged with multiple mutant strains from infection-induced clinical disease, providing a promising strategy for broad-spectrum vaccine development for SARS-CoV-2 prophylaxis. In conclusion, the nanoparticle conjugation platform holds promise for its potential universality and competitive immunization efficacy and is expected to facilitate the rapid manufacturing and broad application of next-generation vaccines.


Assuntos
COVID-19 , Nanopartículas , Animais , Cricetinae , Humanos , SARS-CoV-2 , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Imunidade Inata , Ferritinas/genética , Nanovacinas , Anticorpos Neutralizantes , Anticorpos Antivirais
13.
J Hazard Mater ; 467: 133731, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38340562

RESUMO

In this study Paraccocus versutus XT0.6 was employed to address the mechanism of microbial dissolution and oxidation of stibnite. Results showed that with the growth of XT0.6, pH increased to 9.0 in both microbe-mineral contact (MM) and microbe-mineral non-contact groups (M[M]). Dissolved Sb(III) was released from stibnite, which was subsequently quickly oxidized to Sb(V) completely in MM and partially in M[M] groups. On the contrast, the final pH decreased to 6.5 and 4.9, respectviely, in system amended with extracellular secretion (EM) of XT0.6 and abiotic groups. Dissolution of stibnite and oxidation of Sb(III) were also observed in EM group, suggesting a potential contribution of extracellular enzyme in Sb(III) oxidation. The dissolution and oxidation rates were the highest in MM group, followed by those in M[M], EM and abiotic groups. To be noted, Sb(V) concentration decreased in MM group on the fifth day, which might indicate the formation of Sb(V)-bearing secondary mineral. Genome of XT0.6 consisted of two chromosomes and one plasmid, and most genes responsible for antimony oxidation and antimony resistance were located on the chromosomes. Proteomics analysis of the extracellular secretions indicated the up-regulated proteins were mainly related to electron-transfer, suggesting their potential role in Sb(III) oxidation.


Assuntos
Antimônio , Proteômica , Oxirredução , Transporte de Elétrons , Minerais
14.
Sensors (Basel) ; 24(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38400261

RESUMO

In the field of inter-satellite laser communication, achieving high-quality communication and compensating for the Doppler frequency shift caused by relative motion necessitate lasers with narrow linewidths, low phase noise, and the ability to achieve mode-hop-free tuning within a specific range. To this end, this paper investigates a novel external cavity diode laser (ECDL) with a frequency-selective F-P etalon structure, leveraging the external cavity F-P etalon structure in conjunction with an auxiliary filter to achieve single longitudinal mode selection. The laser undergoes linewidth testing using a delayed self-heterodyne beating method, followed by the testing of its phase noise and frequency noise characteristics using a noise analyzer, yielding beat spectra and noise power spectral density profiles. Furthermore, the paper introduces an innovative bidirectional temperature-scanning laser method to achieve optimal laser-operating point selection and mode-hop-free tuning. The experimental results showcase that the single longitudinal mode spectral side-mode suppression ratio (SMSR) is around 70 dB, and the output power exceeds 10 mW. Enhancing the precision of the F-P etalon leads to a more pronounced suppression of low-frequency phase noise, reducing the Lorentzian linewidth from the initial 10 kHz level to a remarkable 5 kHz level. The bidirectional temperature-scanning laser method not only allows for the selection of the optimal operating point but also enables mode-hop-free tuning within 160 pm.

15.
Front Cell Infect Microbiol ; 14: 1349221, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38357444

RESUMO

Viruses, despite their simple structural composition, engage in intricate and complex interactions with their hosts due to their parasitic nature. A notable demonstration of viral behavior lies in their exploitation of lysosomes, specialized organelles responsible for the breakdown of biomolecules and clearance of foreign substances, to bolster their own replication. The man-nose-6-phosphate (M6P) pathway, crucial for facilitating the proper transport of hydrolases into lysosomes and promoting lysosome maturation, is frequently exploited for viral manipulation in support of replication. Recently, the discovery of lysosomal enzyme trafficking factor (LYSET) as a pivotal regulator within the lysosomal M6P pathway has introduced a fresh perspective on the intricate interplay between viral entry and host factors. This groundbreaking revelation illuminates unexplored dimensions of these interactions. In this review, we endeavor to provide a thorough overview of the M6P pathway and its intricate interplay with viral factors during infection. By consolidating the current understanding in this field, our objective is to establish a valuable reference for the development of antiviral drugs that selectively target the M6P pathway.


Assuntos
Hidrolases , Viroses , Humanos , Hidrolases/metabolismo , Manosefosfatos/análise , Manosefosfatos/química , Manosefosfatos/metabolismo , Viroses/metabolismo , Lisossomos/metabolismo
16.
Environ Res ; 246: 118070, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38157962

RESUMO

BACKGROUND: Type 2 diabetes (T2D) is the most common type of diabetes. However, research on the relationship between blue light exposure and diabetes development is limited. OBJECTIVE: The present study aimed to investigate the relationship between blue light exposure and T2D incidence and whether it is affected by sleep duration, physical activity, outdoor activity time, and genetic susceptibility. METHODS: A total of 471,686 participants without diabetes were recruited from the UK Biobank cohort. T2D incidence was assessed using hospital inpatient records. Blue light exposure was calculated based on the time spent watching TV, using a computer, and playing computer games, which was determined using an online questionnaire. Cox proportional hazards regression models were used to assess the survival relationship between blue light exposure and T2D, as well as the potential modification effects. RESULT: A total of 18,738 cases of T2D were documented during the median follow-up of 13.04 years. After adjusting for potential confounders, the participants with heavy blue light exposure had a greater risk of T2D compared to those with mild blue light exposure (hazard ratio (HR) = 1.17, 95% confidence interval (CI): 1.12-1.23). A significant association between blue light exposure and T2D risk was observed among the participants with heavy physical activity (HR = 1.39, 95%CI: 1.25-1.55), healthy sleep habits (HR = 1.23, 95%CI: 1.10-1.36), higher outdoor activity time (HR = 1.14, 95%CI: 1.07-1.22), or high genetic susceptibility (HR = 1.24, 95%CI: 1.14-1.35). However, this association became non-significant among the participants with low genetic susceptibility (HR = 1.05, 95%CI: 0.97-1.15). CONCLUSION: The present study showed that blue light exposure is associated with a greater risk of T2D independent of classical T2D risk factors.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/etiologia , Estudos Prospectivos , Fatores de Risco , Incidência , Bancos de Espécimes Biológicos , Luz Azul , Biobanco do Reino Unido , Predisposição Genética para Doença
17.
Environ Res ; 245: 118011, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38141916

RESUMO

Microbes have been confirmed to play key role in biogeochemistry of antimony. However, the impact of indigenous bacteria (from active mines) on the behavior of dissolved antimony remained poorly understood. In current study, the hyper antimony-resistant strain, Achromobacter sp. 25-M, isolated from the world largest antimony deposit, Xikuangshan antimony deposit, was evaluated for its role in dissolved Sb(V) and Sb(III) precipitation and removal. Despite of the high resistance to Sb(III) (up to 50 mM), the facultative alkaliphile, 25-M was not capable of Sb(III) oxidation. Meanwhile 25-M can produce high amount of exopolymeric substance (EPS) with the presence of Sb, which prompted us to investigate the potential role of EPS in the precipitation and removal of Sb. To this end, 2 mM of Sb(III) and Sb(V) were added into the experimental systems with and without 25-M to discern the interaction mechanism between microbe and antimony. After 96 hrs' incubation, 88% [1.73 mM (210 mg/L)] of dissolved Sb(V) and 80% [1.57 mM (190 mg/L)] of dissolved Sb(III) were removed. X-ray diffraction and energy dispersive spectroscopy analysis confirmed the formation of valentinite (Sb2O3) in Sb(III) amended system and a solitary Sb(V) mineral mopungite [NaSb(OH)6] in Sb(V) amended group with microbes. Conversely, no precipitate was detected in abiotic systems. Morphologically valentinite was bowtie and mopungite was pseudo-cubic as indicated by scanning electronic microscopy. EPS was subjected to fourier transform infrared (FT-IR) analysis. FT-IR analysis suggested that -OH and -COO groups were responsible for the complexation and ligand exchange with Sb(III) and Sb(V), respectively. Additionally, the C-H group and N-H group could be involved in π-π interaction and chelation with Sb species. All these interactions between Sb and functional groups in EPS may subsequently favore the formation of valentinite and mopungite. Collectively, current results suggested that EPS play fundamental role in bioprecipitation of Sb, which offered a new strategy in Sb bioremediation.


Assuntos
Antimônio , Minerais , Antimônio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Oxirredução , Difração de Raios X , Adsorção
18.
Sci Total Environ ; 913: 169282, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38141989

RESUMO

Coastal wetlands play a vital role in mitigating climate change, yet the characteristics of buried organic carbon (OC) and carbon cycling are limited due to difficulties in assessing the composition of OC from different sources (allochthonous vs. autochthonous). In this study, we analyzed the total organic carbon (TOC) to total nitrogen (TN) ratio (C/N), stable carbon isotope (δ13C) composition, and n-alkane content to distinguish different sources of OC in the surface sediments of the coastal wetlands on the western coast of the Bohai Sea. The coupling of the C/N ratio with δ13C and n-alkane biomarkers has been proved to be an effective tool for revealing OC sources. The three end-member Bayesian mixing model based on coupling C/N ratios with δ13C showed that the sedimentary OC was dominated by the contribution of terrestrial particulate organic matter (POM), followed by freshwater algae and marine phytoplankton, with relative contributions of 47 ± 21 %, 41 ± 18 % and 12 ± 17 %, respectively. The relative contributions of terrestrial plants, aquatic macrophytes and marine phytoplankton assessed by n-alkanes were 56 ± 8 %, 35 ± 9 % and 9 ± 5 % in the study area, respectively. The relatively high salinity levels and strong hydrodynamic conditions of the Beidagang Reservoir led to higher terrestrial plants source and lower aquatic macrophytes source than these of Qilihai Reservoir based on the assessment of n-alkanes. Both methods showed that sedimentary OC was mainly derived from terrestrial sources (plant-dominated), suggesting that vegetation plays a crucial role in storing carbon in coastal wetlands, thus, the coastal vegetation management needs to be strengthened in the future. Our findings provide insights into the origins and dynamics of OC in coastal wetlands on the western coast of the Bohai Sea and a significant scientific basis for future monitoring of the blue carbon budget balance in coastal wetlands.

19.
Med Sci Monit ; 29: e940545, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38062672

RESUMO

BACKGROUND Large cancer lesions are often challenging to treat with surgical intervention alone. Neoadjuvant chemotherapy is frequently used for FIGO stage IB3 and IIA2 cervical cancers to optimize the outcomes of radical surgeries. This study aimed to compare the effectiveness of neoadjuvant chemotherapy, followed by adjuvant chemotherapy and radiotherapy, if necessary, with the traditional approach of adjuvant chemotherapy and radiotherapy after radical hysterectomy in treatment-naïve patients with cervical cancer of specified stages. MATERIAL AND METHODS A total of 245 female patients were administered either 70 to 85 mg/m² cisplatin and 165 to 175 mg/m² paclitaxel every 21 days (2 cycles) prior to radical hysterectomy, followed by adjuvant chemotherapy and radiotherapy if needed (neoadjuvant therapy, NT cohort, n=105), or received adjuvant chemotherapy and radiotherapy after radical hysterectomy adjuvant therapy, AT cohort, n=140). RESULTS In the NT cohort, 76% of patients responded to neoadjuvant chemotherapy, while 24% did not. Adverse operative, intraoperative, and postoperative outcomes were significantly more common among the non-responders (P<0.05). After 5 years, 91% of responders and 72% of non-responders survived without recurrence (P=0.0372), and 3% of responders and 28% of non-responders had died (P=0.0005). CONCLUSIONS The resistance to neoadjuvant chemotherapy is a poor prognostic factor. Neoadjuvant chemotherapy followed by radical hysterectomy and adjuvant chemotherapy/radiotherapy appears to be advantageous for cervical cancer patients who respond well to neoadjuvant chemotherapy.


Assuntos
Terapia Neoadjuvante , Neoplasias do Colo do Útero , Humanos , Feminino , Terapia Neoadjuvante/métodos , Cisplatino/uso terapêutico , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/patologia , Estadiamento de Neoplasias , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Paclitaxel/uso terapêutico , Quimioterapia Adjuvante , Histerectomia/métodos
20.
Antiviral Res ; 220: 105765, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38036065

RESUMO

Coronavirus disease 2019 (COVID-19) seriously threatens public health safety and the global economy, which warrant effective prophylactic and therapeutic approaches. Currently, vaccination and establishment of immunity have significantly reduced the severity and mortality of COVID-19. However, in regard to COVID-19 vaccines, the broad-spectrum protective efficacy against SARS-CoV-2 variants and the blocking of virus transmission need to be further improved. In this study, an optimum oral COVID-19 vaccine candidate, rVSVΔG-Sdelta, was selected from a panel of vesicular stomatitis virus (VSV)-based constructs bearing spike proteins from different SARS-CoV-2 strains. After chitosan modification, rVSVΔG-Sdelta induced both local and peripheral antibody response, particularly, broad-spectrum and long-lasting neutralizing antibodies against SARS-CoV-2 persisted for 1 year. Cross-protection against SARS-CoV-2 WT, Beta, Delta, BA.1, and BA.2 strains was achieved in golden hamsters, which presented as significantly reduced viral replication in the respiratory tract and alleviated pulmonary pathology post SARS-CoV-2 challenge. Overall, this study provides a convenient, oral-delivered, and effective oral mucosal vaccine against COVID-19, which would supplement pools and facilitate the distribution of COVID-19 vaccines.


Assuntos
COVID-19 , Quitosana , Animais , Cricetinae , Humanos , SARS-CoV-2 , Vacinas contra COVID-19 , Mesocricetus , COVID-19/prevenção & controle , Adjuvantes Imunológicos , Anticorpos Neutralizantes , Anticorpos Antivirais , Glicoproteína da Espícula de Coronavírus/genética
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