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1.
Heliyon ; 10(9): e30548, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38765162

RESUMO

Urban expansion often occurs at the expense of cropland loss, posing challenges to sustainable urban growth and food security. However, detailed investigations into urban expansion and cropland loss remain limited, particularly in regions with varying levels of urbanization. Here, we take Guangdong Province, China, as a case study to exemplify how urban expansion affects cropland using remotely sensed land use products. We adopted geospatial analysis, correlation indicators, and landscape metrics to uncover their spatial relationships at 10-m spatial resolutions. Results showed that urban areas increased by 6335 km2 while cropland decreased by 3780 km2 from 2017 to 2022. Notably, 41 % of newly expanded urban areas were from croplands, and 45 % of lost croplands were converted to urban areas. Western Guangdong experienced the largest extent of urban expansion and cropland loss, emerging as a hotspot region in recent years. Additionally, our analysis observed the increasing compactness of urban areas and the growing fragmentation of cropland landscapes over time. These findings shed light on the intricate dynamics between urban expansion and cropland loss in rapidly urbanizing regions, which provide valuable insights for sustainable urban development, agricultural practice, and land management in the future.

2.
Front Immunol ; 15: 1326859, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38361935

RESUMO

The central nervous system (CNS) harbors its own special immune system composed of microglia in the parenchyma, CNS-associated macrophages (CAMs), dendritic cells, monocytes, and the barrier systems within the brain. Recently, advances in the immune cells in the CNS provided new insights to understand the development of tuberculous meningitis (TBM), which is the predominant form of Mycobacterium tuberculosis (M.tb) infection in the CNS and accompanied with high mortality and disability. The development of the CNS requires the protection of immune cells, including macrophages and microglia, during embryogenesis to ensure the accurate development of the CNS and immune response following pathogenic invasion. In this review, we summarize the current understanding on the CNS immune cells during the initiation and development of the TBM. We also explore the interactions of immune cells with the CNS in TBM. In the future, the combination of modern techniques should be applied to explore the role of immune cells of CNS in TBM.


Assuntos
Mycobacterium tuberculosis , Tuberculose Meníngea , Humanos , Sistema Nervoso Central/patologia , Encéfalo/patologia , Microglia/patologia
3.
Front Nutr ; 10: 1177950, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37143474

RESUMO

Introduction: Chlorine dioxide (ClO2) is a safe and efficient bactericide with unique advantages in reducing foodborne illnesses, inhibiting microbial growth, and maintaining the nutritional quality of food. However, gaseous ClO2 is sensitive to heat, vibration, and light, which limits its application. Methods: In this study, a ClO2 precursor-stabilized ClO2 aqueous solution was encapsulated by the double emulsion method, and a high-performance ClO2 self-releasing polyvinyl alcohol (PVA) film was prepared to investigate its performance and effect on blueberry quality during storage. Results: The self-releasing films had the best overall performance when the microcapsule content was 10% as the film's mechanical properties, thermal stability, and film barrier properties were significantly improved. The inhibition rates of Listeria monocytogenes and Escherichia coli were 93.69% and 95.55%, respectively, and the mycelial growth of Staphylococcus griseus was successfully inhibited. The resulting ClO2 self-releasing films were used for blueberry preservation, and an experimental study found that the ClO2 self-releasing antimicrobial film group delayed the quality decline of blueberries. During the 14-day storage period, no mold contamination was observed in the ClO2 self-releasing film group, and blueberries in the antibacterial film group had higher anthocyanin accumulation during the storage period. Discussion: Research analysis showed that films containing ClO2 microcapsules are promising materials for future fruit and vegetable packaging.

4.
Food Chem X ; 18: 100637, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-36949750

RESUMO

The research of starch retrogradation have been attracting interest. Thereby, the long-term retrogradation mechanism (0-21 days) of Pouteria campechiana seed starch (PCSS) was investigated. The results showed that crystal type was changed from A- to B + V-type during retrogradation. The retrogradation PCSS (RPCSS) exhibited faster retrogradation rate and more compact internal ultra-structure compared to rice, wheat and maize starch. Pearson correlation indicated that, as retrogradation days increased, values of α-1,4-glycosidic bond, A chains, double helix, V-type polymorphism, Mw, relative crystallinity (Rc) and short-range order gradually significantly increased, and B1 chains, B3 + chains values gradually significantly dropped (p < 0.05). These inferred an increasing peak temperature and compactness of morphology with increasing retrogradation days. Compared to native starch, RPCSS α-1.4-glycosidic bond was increased, which indicated that its quick molecules degradation including decreased Mw, B3 + chains, Rc, semicrystalline order, and ΔH. These might provide a theoretical direction for preparation of starch-basis food.

5.
Orthop J Sports Med ; 10(8): 23259671221115743, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36051971

RESUMO

Background: Rotator cuff pathology is a common cause of pain and shoulder dysfunction. Several nonoperative treatment modalities have been developed for rotator cuff lesions, but their relative efficacy is not well-established. Purpose/Hypothesis: The purpose of this systematic review and meta-analysis was to evaluate the efficacy and safety of sodium hyaluronate (SH) in the treatment of patients with rotator cuff lesions. It was hypothesized that SH would be found to be more effective than other nonoperative regimens. Study Design: Systematic review; Level of evidence, 3. Methods: We searched various databases to identify eligible studies that evaluated the effects of SH on the pain and shoulder dysfunction attributed to rotator cuff lesions. Outcome measures were pain visual analog scale (VAS) score; Constant score; University of California, Los Angeles (UCLA) score; satisfaction rate; complications; and factors affecting the pain VAS score. Outcomes were reported as weighted mean difference (WMD) or risk ratio. Results: A total of 9 studies were identified for data analysis. Compared with patients treated with other nonoperative treatments (controls), those treated with SH had significantly improved pain VAS scores at 1 week (WMD = -0.95; 95% CI, -1.75 to -0.16; P = .019), 2 weeks (WMD = -1.05; 95% CI, -2.07 to -0.03; P = .044), 3 weeks (WMD = -1.49; 95% CI, -2.88 to -0.11; P = .035), and 4 weeks (WMD = -2.12; 95% CI, -4.05 to -0.19; P = .031). The Constant score was significantly improved in the SH group versus controls at 2 weeks (WMD = 3.25; 95% CI, 2.36 to 4.13; P < .001), 3 months (WMD = 20.28; 95% CI, 0.54 to 40.03; P = .044), and 6 months (WMD = 5.58; 95% CI, 0.94 to 10.21; P = .018). The UCLA score and satisfaction rate did not differ significantly between the 2 groups. No complications associated with SH were reported in the included studies. Metaregression analysis showed that, except for study design (coefficient = -1.64; 95% CI, -2.64 to -0.63; P = .002), none of the variables (sample size, tear type, control treatments) significantly predicted the difference in VAS pain score between SH and other treatments. Conclusion: The present meta-analysis demonstrated that SH was effective in treating patients with rotator cuff lesions.

7.
J Agric Food Chem ; 69(11): 3452-3465, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33724017

RESUMO

An efficient technique using citric acid and glucose based natural deep eutectic solvent (G-C-NADES) was developed to obtain ultrahigh deamidated wheat gluten (UDWG) (deamidation degree (DD) > 90%). FTIR and 1H NMR indicated intensive hydrogen bonds (HBs) in G-C-NADES supermolecules. Quantum chemical calculations and molecular dynamic simulations demonstrated that 10 wt % diluted G-C-NADES still had a myriad of HBs. Physicochemical results showed UDWG had DD up to 92.45% after G-C-NADES deamidation, that is, 22% higher than citric-acid-DWG with a weak degree of hydrolysis (1.75%). Conformational characterization demonstrated the obvious conversion from α-helix to ß-sheet via FTIR, the least amount of disulfide bonds by Raman spectra, and more exposure of tryptophan residues by fluorescence measurement for UDWG. It is proven that enhanced accessible conformation of WG reached with HBs of G-C-NADESs could contribute to the improvement on nucleophilic attack of deamidation, declaring that G-C-NADES might be a potential solvent for obtaining an ultrahigh deamidation for WG to successfully guarantee the safety of wheat gluten based cereal food regarding to lowering its allergy.


Assuntos
Ácido Cítrico , Triticum , Glucose , Glutens , Solventes
8.
Carbohydr Polym ; 257: 117557, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33541626

RESUMO

Coix seed oil (CSO) is easily suffered functional-loss by oxidation and hydrothermal-treatment. The environmental stable nanocage-coating-CSO particles (OGC-Ca) by the frameworks consist of gliadins, carboxymethyl chitosan (CMCS) and Ca2+ were investigated. Results showed Ca2+ was the key controller for fabricating this nanocage-coating-frameworks, bridging macromolecule-chains with electrostatic interaction and hydrogen bonds, detected by FTIR, CD, DSC and XRD. SEM displayed new-formed velvet-like twigs after cross-linking CMCS to gliadins. Ca2+ assisted the nanocage-coating by significant down-sizing conversion OGC to OGC-Ca with consumption of twigs. OGC-Ca displayed a good stability towards heat (60-80 °C, 0-80 min), pH (3-8), NaCl (0-0.5 mM), storage (4/25 °C, 12 days), and a reduce of the pre-oxidation value of CSO in water and the improved controlled release of CSO in simulated GI tract. It illustrated GC-Ca frameworks would be a suitable delivery carrier for the CSO like pharmaceuticals and nutraceuticals for the food or medical use.

9.
Mikrochim Acta ; 187(8): 437, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32647943

RESUMO

Gold nanoparticles (AuNPs) conjugated with Cy3-tagged aptamer which can specifically recognize chloramphenicol (CAP) (referred to as AuNPs-AptCAP) are described. CAP can trigger the configuration change of CAP binding aptamer, and thus switching the fluorescence of AuNPs-AptCAP through changing the efficiency of the fluorescence resonance energy transfer (FRET) system with Cy3 as donors and AuNPs as recipients. AuNPs-AptCAP exhibits a linear range of CAP concentrations from 26.0 to 277 µg L-1 with a limit of detection of 8.1 µg L-1 when Cy3 was excited at 530 nm and emission was measured at 570 nm. More importantly, AuNPs-AptCAP can be utilized as signal transducers for the build-up of a series of logic gates including YES, PASS 0, INH, NOT, PASS 1, and NAND. Utilizing the principle of a metal ion-mediated fluorescence switch together with a strong metal ion chelator, the fluorescence of AuNPs-AptCAP could be modulated by adding metal ions and EDTA sequentially. Therefore, a "Plug and Play" logic system based on AuNPs-AptCAP has been realized by simply adding other components to create new logic functions. This work highlights the advantages of simple synthesis and facile fluorescence switching properties, which will provide useful knowledge for the establishment of molecular logic systems. Graphical abstract.


Assuntos
Aptâmeros de Nucleotídeos/química , Carbocianinas/química , Corantes Fluorescentes/química , Lógica , Nanopartículas Metálicas/química , Sequência de Bases , Cloranfenicol/química , DNA/química , Ácido Edético/química , Fluorescência , Transferência Ressonante de Energia de Fluorescência , Ouro/química , Ácidos Nucleicos Imobilizados/química , Limite de Detecção , Mercúrio/química , Níquel/química
10.
J Cancer ; 9(21): 4087-4091, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30410613

RESUMO

Neoadjuvant chemotherapy (NACT) plays an important role in ovarian cancer. The appropriate time interval from the completion of NACT to interval debulking surgery (TTS) in ovarian cancer is still unknown. The aim of this retrospective study was to evaluate the effect of the time interval between the end of NACT and surgery (TTS ≤ 4 weeks vs TTS > 4 weeks) on the survival outcomes among patients with advanced-stage ovarian, tubal, and peritoneal cancers. 152 patients with stage III or IV ovarian, tubal, and peritoneal cancers were included in this retrospective cohort study: 115 in the TTS ≤4 weeks and 37 in the TTS >4 weeks groups. The Kaplan-Meier analysis showed that the progression-free survival in the TTS ≤4 weeks group was longer than that in the TTS >4 weeks group (26 vs 14 months, P=0.04). However, the overall survival was not different between the two groups (66 vs 36 months, P=0.105). The multivariate analysis presented that delay in surgery after NACT (TTS >4 weeks) was associated with a shorter progression-free (P=0.002) but not overall survival (P=0.231). Our findings demonstrated no relationship between the NACT to surgery interval and OS, while a detrimental effect of TTS >4 weeks on PFS was observed.

11.
Environ Sci Pollut Res Int ; 23(12): 12075-84, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26965277

RESUMO

Amounts of landslide deposits were triggered by the Wenchuan earthquake with magnitude 8.0 on May 12, 2008. The landslide deposits were composed of soil and rock fragments, which play important roles in hydrological and erosion processes in the steep slope of landslide deposits. The mixtures of soil and gravels are common in the top layers of landslide deposits, and its processes are obviously different with the soil without gravels. Based on the data of field investigation, a series of simulated scouring flow experiments with four proportion of gravel (0, 25, 33.3, and 50 %) and three scouring flow rates (4, 8, 12 L/min) under two steep slopes (67.5, 72.7 %) were conducted sequentially to know the effects of proportion of gravel on infiltration capacity, runoff generation, and sediment production in the steep slope of landslide deposit. Results indicated that gravel had promoted or reduced effects on infiltration capacity which could affect further the cumulative runoff volume and cumulative sediment mass increase or decrease. The cumulative infiltration volume in 25 % proportion of gravel was less than those in 0, 33.3, and 50 % proportion of gravel. The cumulative runoff volume was in an order of 25 > 0 > 33.3 > 50 % while cumulative sediment mass ranked as 25 > 33.3 > 0 > 50 % with different proportions of gravel. A significant power relationship was found between scouring time and cumulative runoff volume as well as cumulative sediment mass. The relationship between average soil and water loss rate and proportion of gravel was able to express by quadratic function, with a high degree of reliability. The results have important implications for soil and water conservation and modeling in landslide deposit but also provide useful information for the similar conditions.


Assuntos
Terremotos , Sedimentos Geológicos , Deslizamentos de Terra , China , Hidrologia , Solo
12.
ACS Appl Mater Interfaces ; 8(14): 9472-82, 2016 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-27007856

RESUMO

In this study, two new functionalized polyethylenimine (PEI), PEIR and PEIQ, have been synthesized by covalently conjugating rhodamine 6G (R6G) or 8-chloroacetyl-aminoquinoline (CAAQ) and have been investigated for their sensing capabilities toward metal ions and anions basing on fluorescence on-off and off-on mechanisms. When triggered by protons, metal ions, or anions, functionalized PEIs can behave as a fluorescence switch, leading to a multiaddressable system. Inspired by these results, functionalized PEI-based logic systems capable of performing elementary logic operations (YES, NOT, NOR, and INHIBIT) and integrative logic operations (OR + INHIBIT) have been constructed by observing the change in the fluorescence with varying the chemical inputs such as protons, metal ions, and anions. Due to its characteristics, such as high sensitivity and fast response, developing functionalized PEI as a new material to perform logic operations may pave a new avenue to construct the next generation of molecular devices with better applicability for biomedical research.


Assuntos
Computadores Moleculares , Polietilenoimina/química , Aminoquinolinas/química , Fluorescência , Íons/química , Metais/química , Polietilenoimina/síntese química , Prótons , Rodaminas/química
13.
Tumour Biol ; 35(5): 4357-62, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24375257

RESUMO

Limited information is available concerning the clinicopathologic profile of colorectal gastrointestinal stromal tumors (GISTs), which are relatively rare, as well as survival rates following surgical resection. The present study was designed to describe the clinicopathologic characteristics of patients with colorectal GISTs and identify potential factors that may predict postoperative survival outcomes. We reviewed the medical records of 67 patients with colorectal GISTs who underwent surgical resection between January 2000 and December 2012. Clinicopathologic factors affecting overall survival were assessed using the Kaplan-Meier method and multivariate Cox proportional hazards models. The median age at diagnosis was 57 years (range, 32-79 years), with a male-to-female ratio of 1.68. Tumor size varied from 0.2 to 11 cm, with a median size of 5.7 cm. Sixty-two tumors (93%) were positive for CD117, 53 (79%) for CD34, 6 (9%) for PDGFRA, 15 (22%) for SMA, 5 (8%) for S100, and 39 (58%) for vimentin. The overall median survival time was 54 months (95% confidence interval, 32-59 months), and the 1-, 3-, and 5-year overall survival rates were 89.6, 63.9, and 34.4%, respectively. High-risk tumors (determined by histologic grade, size, and other histologic variables) were associated with poor prognosis (hazard ratio, 1.83; 95% confidence interval, 1.21-2.78), and patients who received adjuvant treatment with imatinib had significantly longer median overall survival times than patients who did not (hazard ratio, 0.43; 95% confidence interval, 0.24-0.80). In patients with colorectal GISTs, high-risk tumor histologic grade can predict poor prognosis, and patients may benefit from adjuvant treatment with imatinib. Findings from the present study may provide information to establish evidence-based management strategies for colorectal GISTs.


Assuntos
Neoplasias Colorretais/patologia , Tumores do Estroma Gastrointestinal/patologia , Adulto , Idoso , Neoplasias Colorretais/mortalidade , Feminino , Tumores do Estroma Gastrointestinal/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Taxa de Sobrevida
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