Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 31
Filter
2.
Blood Press Monit ; 28(5): 268-275, 2023 Oct 01.
Article in English | MEDLINE | ID: mdl-37382121

ABSTRACT

OBJECTIVE: We used our established database to investigate predialysis blood pressure (BP) measurements at different time points. METHODS: Our study period spanned from 1 January 2019 to 31 December 2019. The different time points included: the long interdialytic interval versus the short interdialytic interval; different hemodialysis shifts. Multiple linear regression was used to explore the association between BP measurements and different time points. RESULTS: A total of 37 081 cases of hemodialysis therapies were included. After a long interdialytic interval, predialysis SBP and DBP were significantly elevated. Predialysis BP was 147.72/86.73 mmHg on Monday and 148.26/86.52 mmHg on Tuesday, respectively. Both predialysis SBP and DBP were higher in the a.m. shift. The mean BP in the a.m. and p.m. shifts were 147.56/87 mmHg and 144.83/84.64 mmHg, respectively. In both diabetic nephropathy and non-diabetic nephropathy patients, higher SBP measurements after a long interdialytic interval were observed; however, in diabetic nephropathy patients, we did not find significant differences in DBP among different dates. In diabetic nephropathy and non-diabetic nephropathy patients, we observed that the effect of different shifts on BP was similar. In Monday, Wednesday and Friday subgroups, the long interdialytic interval was also associated with BP; however, in Tuesday, Thursday and Saturday subgroups, different shifts but not the long interdialytic interval was associated with BP. CONCLUSION: The long interdialytic interval and different hemodialysis shifts have a significant effect on predialysis BP in patients with hemodialysis. When interpreting BP in patients with hemodialysis, different time points is a confounder.


Subject(s)
Kidney Failure, Chronic , Renal Dialysis , Humans , Blood Pressure/physiology , Arterial Pressure , Blood Pressure Determination , Blood Pressure Monitoring, Ambulatory , Kidney Failure, Chronic/complications
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 297: 122739, 2023 Sep 05.
Article in English | MEDLINE | ID: mdl-37084684

ABSTRACT

Hydrogen sulfide (H2S) is an endogenously generated gaseous signaling molecule and is known to be involved in the occurrence and development of inflammation. To better understand its physiological and pathological process of inflammation, reliable tools for H2S detection in living inflammatory models are desired. Although a number of fluorescent sensors have been reported for H2S detection and imaging, water-soluble and biocompatibility nanosensors are more useful for imaging in vivo. Herein, we developed a novel biological imaging nanosensor, XNP1, for inflammation-targeted imaging of H2S. XNP1 was obtained by self-assembly of amphiphilic XNP1, which was constructed by the condensation reaction of the hydrophobic, H2S response and deep red-emitting fluorophore with hydrophilic biopolymer glycol chitosan (GC). Without H2S, XNP1 showed very low background fluorescence, while a significant enhancement in the fluorescence intensity of XNP1 was observed in the presence of H2S, resulting in a high sensitivity toward H2S in aqueous solution with a practical detection limit as low as 32.3 nM, which could be meet the detection of H2S in vivo. XNP1 also has a good linear response concentration range (0-1 µM) toward H2S with high selectivity over other competing species. These characteristics facilitate direct H2S detection of the complex living inflammatory cells and drug-induced inflammatory mice, demonstrating its practical application in biosystems.


Subject(s)
Fluorescent Dyes , Hydrogen Sulfide , Humans , Mice , Animals , HeLa Cells , Fluorescent Dyes/chemistry , Microscopy, Fluorescence , Optical Imaging , Hydrogen Sulfide/chemistry , Inflammation/diagnostic imaging
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 295: 122624, 2023 Jul 05.
Article in English | MEDLINE | ID: mdl-36933443

ABSTRACT

Peroxynitrite (OONO-) is closely related to the occurrence and development of health and inflammatory diseases. The physiological and pathological results of OONO- are related to the local concentration of ONOO-. Therefore, to develop of a simple, rapid and reliable OONO- detection tool is badly needed. In this work, we developed a small-molecule near-infrared (NIR) turn-on fluorescence sensor (NN1), harnessing a well-known response group phenylboronic acid response toward OONO-. It shows high detection sensitivity and yields a ratio (I658/I0) fluorescence enhancement (∼280-fold). In addition, NN1 can be effectively used to detect endogenous and exogenous ONOO- in living inflammatory cells. Notably, NN1 can be applied to OONO- imaging analysis in drug-induced inflammatory mice model with satisfactory results. Therefore, NN1 is a robust molecular biological tool, which has a good prospect in the study of ONOO- and the occurrence and development of inflammatory diseases.


Subject(s)
Diagnostic Imaging , Fluorescent Dyes , Animals , Mice , Fluorescence , Peroxynitrous Acid/analysis , Optical Imaging
5.
Plants (Basel) ; 12(3)2023 Feb 03.
Article in English | MEDLINE | ID: mdl-36771765

ABSTRACT

Crop production encounters challenges due to the dearth of nitrogen (N) and phosphorus (P), while excessive chemical fertilizer use causes environmental hazards. The use of N-fixing microbes and P-solubilizing microbes (PSMs) can be a sustainable strategy to overcome these problems. Here, we conducted a greenhouse pot experiment following a completely randomized blocked design to elucidate the influence of co-inoculating N-fixing bacteria (Bradyrhizobium japonicum) and PSMs (Saccharomyces cerevisiae and Saccharomyces exiguus) on atmospheric N2-fixation, growth, and yield. The results indicate a significant influence of interaction on Indole-3-acetic acid production, P solubilization, seedling germination, and growth. It was also found that atmospheric N2-fixation, nodule number per plant, nodule dry weight, straw, and root dry weight per plant at different growth stages were significantly increased under dual inoculation treatments relative to single inoculation or no inoculation treatment. Increased seed yield and N and P accumulation were also noticed under co-inoculation treatments. Soil available N was highest under sole bacterial inoculation and lowest under the control treatment, while soil available P was highest under co-inoculation treatments and lowest under the control treatment. We demonstrated that the co-inoculation of N-fixing bacteria and PSMs enhances P bioavailability and atmospheric N2-fixation in soybeans leading to improved soil fertility, raising crop yields, and promoting sustainable agriculture.

6.
Appl Opt ; 62(4): 1046-1056, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36821162

ABSTRACT

A broadband and CMOS-compatible polarization beam splitter and rotator (PSR) built on the silicon nitride-on-silicon multilayer platform is presented. The PSR is realized by cascading a polarization beam splitter and a polarization rotator, which are both subtly constructed with an asymmetrical directional coupler waveguide structure. The advantage of this device is that the function of PSR can be directly realized in the SiN layer, providing a promising solution to the polarization diversity schemes in SiN photonic circuits. The chip is expected to have high power handling capability as the light is input from the SiN waveguide. The use of silicon dioxide as the upper cladding of the device ensures its compatibility with the metal back-end-of-line process. By optimizing the structure parameters, a polarization conversion loss lower than 1 dB and cross talk larger than 27.6 dB can be obtained for TM-TE mode conversion over a wavelength range of 1450 to 1600 nm. For TE mode, the insertion loss is lower than 0.26 dB and cross talk is larger than 25.3 dB over the same wavelength range. The proposed device has good potential in diversifying the functionalities of the multilayer photonic chip with high integration density.

7.
BMC Genomics ; 24(1): 27, 2023 Jan 17.
Article in English | MEDLINE | ID: mdl-36650452

ABSTRACT

BACKGROUND: As an economically important crop, tea is strongly nitrogen (N)-dependent. However, the physiological and molecular mechanisms underlying the response of N deficiency in tea are not fully understood. Tea cultivar "Chunlv2" [Camellia sinensis (L.) O. Kuntze] were cultured with a nutrient solution with 0 mM [N-deficiency] or 3 mM (Control) NH4NO3 in 6 L pottery pots containing clean river sands. RESULTS: N deficiency significantly decreased N content, dry weight, chlorophyll (Chl) content, L-theanine and the activities of N metabolism-related enzymes, but increased the content of total flavonoids and polyphenols in tea leaves. N deficiency delayed the sprouting time of tea buds. By using the RNA-seq technique and subsequent bioinformatics analysis, 3050 up-regulated and 2688 down-regulated differentially expressed genes (DEGs) were isolated in tea leaves in response to N deficiency. However, only 1025 genes were up-regulated and 744 down-regulated in roots. Gene ontology (GO) term enrichment analysis showed that 205 DEGs in tea leaves were enriched in seven GO terms and 152 DEGs in tea roots were enriched in 11 GO items based on P < 0.05. In tea leaves, most GO-enriched DEGs were involved in chlorophyll a/b binding activities, photosynthetic performance, and transport activities. But most of the DEGs in tea roots were involved in the metabolism of carbohydrates and plant hormones with regard to the GO terms of biological processes. N deficiency significantly increased the expression level of phosphate transporter genes, which indicated that N deficiency might impair phosphorus metabolism in tea leaves. Furthermore, some DEGs, such as probable anion transporter 3 and high-affinity nitrate transporter 2.7, might be of great potential in improving the tolerance of N deficiency in tea plants and further study could work on this area in the future. CONCLUSIONS: Our results indicated N deficiency inhibited the growth of tea plant, which might be due to altered N metabolism and expression levels of DEGs involved in the photosynthetic performance, transport activity and oxidation-reduction processes.


Subject(s)
Camellia sinensis , Camellia sinensis/metabolism , Chlorophyll A , Nitrogen/metabolism , Tea/metabolism , Plant Leaves/metabolism , Plant Proteins/genetics , Plant Proteins/metabolism , Gene Expression Regulation, Plant
8.
Environ Sci Pollut Res Int ; 30(11): 29243-29257, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36409416

ABSTRACT

The purpose of this paper is to quantify the level of new-type urbanization and unravel the spatial and nonlinear effects of new-type urbanization and technological innovation on industrial carbon emissions. Although the impact of traditional urbanization levels on carbon emissions has been widely studied, there is still a huge room for optimization, and the impact of new-type urbanization on carbon emissions has not yet been clarified. Selecting 37 cities in the Yangtze River Delta as a research sample, this paper measures the new-type urbanization based on an evaluation system we build. Consequently, we assess the spatial and nonlinear effects of new-type urbanization and technological innovation on carbon emissions by the spatial Durbin model and non-parameter addictive model, respectively. The results indicate that the new-type urbanization and low-carbon city pilot policy have significant spatial spillover effects on reducing carbon dioxide emissions, while the economic growth plays a positive role in increasing carbon emission. As for nonlinear effects, there is a significant inverted "N"-shaped relationship between the level of new-type urbanization and carbon dioxide emissions, while the nexus between technological innovation and carbon emissions is an inverted "U"-shaped relationship. This paper provides a new perspective for confirming the mechanism of the new-type urbanization on carbon emissions. Meanwhile, these findings are of significance for the relevant authorities in China to develop appropriate policy in carbon dioxide emission reduction.


Subject(s)
Carbon Dioxide , Urbanization , Carbon Dioxide/analysis , Inventions , Rivers , Industry , Cities , Economic Development , China
9.
Int J Mol Sci ; 25(1)2023 Dec 23.
Article in English | MEDLINE | ID: mdl-38203412

ABSTRACT

Leaf color variations in tea plants were widely considered due to their attractive phenotypes and characteristic flavors. The molecular mechanism of color formation was extensively investigated. But few studies focused on the transformation process of leaf color change. In this study, four strains of 'Baijiguan' F1 half-sib generation with similar genetic backgrounds but different colors were used as materials, including Green (G), Yellow-Green (Y-G), Yellow (Y), and Yellow-Red (Y-R). The results of broadly targeted metabolomics showed that 47 metabolites were differentially accumulated in etiolated leaves (Y-G, Y, and Y-R) as compared with G. Among them, lipids were the main downregulated primary metabolites in etiolated leaves, which were closely linked with the thylakoid membrane and chloroplast structure. Flavones and flavonols were the dominant upregulated secondary metabolites in etiolated leaves, which might be a repair strategy for reducing the negative effects of dysfunctional chloroplasts. Further integrated analysis with the transcriptome indicated different variation mechanisms of leaf phenotype in Y-G, Y, and Y-R. The leaf color formation of Y-G and Y was largely determined by the increased content of eriodictyol-7-O-neohesperidoside and the enhanced activities of its modification process, while the color formation of Y-R depended on the increased contents of apigenin derivates and the vigorous processes of their transportation and transcription factor regulation. The key candidate genes, including UDPG, HCT, CsGSTF1, AN1/CsMYB75, and bHLH62, might play important roles in the flavonoid pathway.


Subject(s)
Camellia sinensis , Camellia sinensis/genetics , Camellia sinensis/metabolism , Metabolome , Plant Leaves/metabolism , Transcriptome
10.
Appl Opt ; 61(26): 7798-7806, 2022 Sep 10.
Article in English | MEDLINE | ID: mdl-36256383

ABSTRACT

A CMOS-compatible, broadband, and polarization-independent edge coupler for efficient chip coupling with standard single-mode fiber is proposed. Three layers of a silicon nitride waveguide array with the same structures are used in the top oxide cladding of the chip to achieve high coupling efficiency and to simplify the mode transformation structure. Optimal total coupling loss at the wavelength of 1550 nm, -0.49dB for TE mode polarization and -0.92dB for TM mode polarization is obtained. The -1dB bandwidth is beyond 160 nm for TE mode polarization and ∼130nm for TM mode polarization, respectively. A significant reduction in the packaging cost of silicon photonic chips is anticipated. Meanwhile, the structure holds vast potential for on-chip three-dimensional photonic integrations or fiber-to-chip, chip-to-chip optical interconnections.

11.
Medicine (Baltimore) ; 101(35): e30293, 2022 Sep 02.
Article in English | MEDLINE | ID: mdl-36107545

ABSTRACT

BACKGROUND: Cellular angiofibroma (CAF), a rare benign mesenchymal tumor, is histologically characterized by abundant thick-walled vessels with a spindle cell component. As one of the female reproductive system tumors, its clinical and pathological features are not well characterized. METHODS: A 47-year-old woman presented for the removal of intrauterine device on October 28, 2021, as she had achieved menopause one year back. The patient had no discomfort or awareness of any mass in her vagina. She has history of breast cancer and papillary thyroid cancer. Till date, no progression of thyroid cancer or breast cancer has been observed. Her menstrual cycle was regular, and she had one child delivered vaginally. RESULTS: Pelvic examination revealed a mass sized 2.5 × 2.0 cm located near the fornix in the upper segment of the left vaginal wall. Thin prep cytologic test (TCT) revealed negative intraepithelial lesion or malignancy (NILM). HPV test was negative and leucorrhea routine inspection cleanliness II degree. No cervical mass was detected by ultrasound examination. The patients underwent the operation for intrauterine device removal plus vaginal tumor resection on November 1, 2021. Postoperative antibiotics (intravenous cefuroxime sodium 0.75 g bid for 1 day) were administered to prevent infection. The patient showed no signs of recurrence at one-month follow-up. CONCLUSION: In summary, CAF is a rare benign soft tissue tumor. Surgery is the only treatment method, and the definitive diagnosis of CAF is based on histopathological examination of surgical specimen. Long-term follow-up is needed for surveillance of recurrence.


Subject(s)
Angiofibroma , Breast Neoplasms , Angiofibroma/diagnosis , Angiofibroma/pathology , Angiofibroma/surgery , Cefuroxime , Female , Humans , Middle Aged , Sodium , Vagina/pathology , Vagina/surgery
12.
BMC Plant Biol ; 22(1): 319, 2022 Jul 04.
Article in English | MEDLINE | ID: mdl-35787241

ABSTRACT

BACKGROUND: Tea plant breeding or cultivation mainly involves propagation via cuttings, which not only ensures the inheritance of the excellent characteristics of the mother plant but also facilitates mechanized management. The formation of adventitious root (AR) determines the success of cutting-based propagation, and auxin is an essential factor involved in this process. To understand the molecular mechanism underlying AR formation in nodal tea cuttings, transcriptome and endogenous hormone analysis was performed on the stem bases of red (mature)- and green (immature)-stem cuttings of 'Echa 1 hao' tea plant as affected by a pulse treatment with naphthalene acetic acid (NAA). RESULTS: In this study, NAA significantly promoted AR formation in both red- and green-stem cuttings but slightly reduced callus formation. External application of NAA reduced the levels of endogenous indole-3-acetic acid (IAA) and cytokinin (TZR, trans-zeatin riboside). The number of DEGs (NAA vs. CK) identified in the green-stem cuttings was significantly higher than that in the red-stem cuttings, which corresponded to a higher rooting rate of green-stem cuttings under the NAA treatment. A total of 82 common DEGs were identified as being hormone-related and involved in the auxin, cytokinin, abscisic acid, ethylene, salicylic acid, brassinosteroid, and jasmonic acid pathways. The negative regulation of NAA-induced IAA and GH3 genes may explain the decrease of endogenous IAA. NAA reduced endogenous cytokinin levels and further downregulated the expression of cytokinin signalling-related genes. By the use of weighted gene co-expression network analysis (WGCNA), several hub genes, including three [cellulose synthase (CSLD2), SHAVEN3-like 1 (SVL1), SMALL AUXIN UP RNA (SAUR21)] that are highly related to root development in other crops, were identified that might play important roles in AR formation in tea cuttings. CONCLUSIONS: NAA promotes the formation of AR of tea cuttings in coordination with endogenous hormones. The most important endogenous AR inductor, IAA, was reduced in response to NAA. DEGs potentially involved in NAA-mediated AR formation of tea plant stem cuttings were identified via comparative transcriptome analysis. Several hub genes, such as CSLD2, SVL1 and SAUR21, were identified that might play important roles in AR formation in tea cuttings.


Subject(s)
Camellia sinensis , Acetates/metabolism , Camellia sinensis/genetics , Camellia sinensis/metabolism , Cytokinins/metabolism , Hormones/metabolism , Indoleacetic Acids/metabolism , Naphthalenes/metabolism , Plant Breeding , Plant Roots/metabolism , Tea , Transcriptome
13.
BMC Cancer ; 22(1): 657, 2022 Jun 14.
Article in English | MEDLINE | ID: mdl-35701738

ABSTRACT

BACKGROUND AND PURPOSE: We aimed to explore the necessity of the external iliac lymph nodes (EIN) along with inguinal nodes (IN) region in clinical target volume (CTV) for rectal carcinomas covering the anal canal region. MATERIALS AND METHODS: This research premise enrolled 399 patients who had primary low rectal cancer detected below the peritoneal reflection via magnetic resonance imaging (MRI) and were treated with neoadjuvant radiotherapy (NRT), without elective EIN along with IN irradiation. We stratified the patients into two groups based on whether the lower edge of the rectal tumor extended to the anal canal (P group, n = 109) or not (Rb group, n = 290). Comparison of overall survival (OS), locoregional recurrence-free survival (LRFS), disease-free survival (DFS), as well as distant metastasis-free survival (DMFS) were performed via inverse probability of treatment weighting (IPTW) along with multivariable analyses. We compared the EIN and IN failure rates between the two groups via the Fisher and Gray's test. RESULTS: P group showed a similar adjusted proportion along with five-year cumulative rate of EIN failure compared with the Rb group. The adjusted proportion and five-year cumulative rate of IN failure in the P group was higher in comparison to the Rb group. There were no remarkable differences in the adjusted five-year OS, DFS, DMFS or LRFS between the two groups. Anal canal involvement (ACI) exhibited no effect on OS, LRFS, DFS, or DMFS. CONCLUSIONS: During NRT for rectal cancer with ACI, it may be possible to exclude the EIN and IN from the CTV.


Subject(s)
Lymphadenopathy , Rectal Neoplasms , Anal Canal/pathology , Humans , Lymph Nodes/pathology , Lymphadenopathy/pathology , Neoplasm Recurrence, Local/pathology , Neoplasm Staging , Pelvis/pathology , Prognosis , Rectal Neoplasms/pathology , Retrospective Studies
14.
Front Cardiovasc Med ; 9: 820483, 2022.
Article in English | MEDLINE | ID: mdl-35369290

ABSTRACT

Objective: To investigate a seasonal variation in blood pressure (BP) for patients undergoing hemodialysis (HD). Methods: In this retrospective study, we exported all BP measurements from the information system to investigate a seasonal variation of BP. We also investigated a seasonal variation in BP for patients of different gender types, of different age groups, with diabetic nephropathy (DN), and with non-DN having HD. Multiple linear regression models were used to explore the associations between BP and climatic parameters. Results: In 2019, a total of 367 patients had received HD therapy in the Longwen HD unit. We included nearly 40,000 pre-dialysis BP measurements. The result of our study demonstrated a clear seasonal variation in pre-dialysis BP in general patients with HD, in male and female patients, and patients with DN and non-DN. December seemed to be a peak in the values of pre-dialysis systolic BP (SBP) and diastolic BP (DBP). The nadir values of pre-dialysis SBP and DBP were observed in June and July, respectively. A difference between peak and nadir values of BP is 3.81/2.20 mmHg in patients undergoing HD. Maximal seasonal variation in BP is 9.03/5.08 mmHg for patients with DN. A significant association of SBP and DBP with climatic parameters was found in this study. Pre-dialysis BP was inversely correlated with outdoor temperature, daytime length, and relative humidity. Conclusion: A clear seasonal variation in BP is observed for patients with HD. Pre-dialysis SBP and DBP are inversely associated with outdoor temperature, daytime length, and relative humidity. The magnitude of a seasonal variation in BP increases in patients with DN.

15.
Int Immunopharmacol ; 106: 108564, 2022 May.
Article in English | MEDLINE | ID: mdl-35158228

ABSTRACT

The gut is hypothesized to be the "motor" of critical illness and plays an important role in the development of sepsis. Berberine (BBR) is an alkaloid compound extracted from herbs, which has anti-inflammatory, anti-oxidative effects and can be used in intestinal infectious diseases and inflammatory bowel disease (IBD). BBR could promote differentiation of Treg cells which play a key role in maintaining intestinal immune homeostasis. However, its effect on sepsis-induced intestinal injury remains poorly understood. This study investigated the effect of BBR on cecal ligation and puncture (CLP)-induced intestinal injury and explained the underlying mechanism. These results showed that BBR treatment decreased the mortality of septic mice, alleviated intestinal injury and reduced serum endotoxin level; at the same time, BBR had a protective effect on CLP-induced lung and liver apoptosis. Meanwhile, BBR treatment increased the proportion of Treg cells and CTLA-4 in Treg cells. Treg cells from BBR treatment mice could decrease the pro-inflammatory response by inhibiting the activation of macrophages, thus exerting a protective effect on CLP-induced intestinal injury, and CTLA-4 mediated cell-cell contact pathway is required for this protective effect.


Subject(s)
Berberine , Sepsis , Animals , Berberine/pharmacology , Berberine/therapeutic use , Cecum/surgery , Ligation , Mice , Punctures , Sepsis/drug therapy , T-Lymphocytes, Regulatory
17.
Front Plant Sci ; 13: 1033316, 2022.
Article in English | MEDLINE | ID: mdl-36589051

ABSTRACT

Caffeine is a characteristic secondary metabolite in tea plants. It confers tea beverage with unique flavor and excitation effect on human body. The pathway of caffeine biosynthesis has been generally established, but the mechanism of caffeine transport remains unclear. Here, eight members of purine permeases (PUPs) were identified in tea plants. They had diverse expression patterns in different tissues, suggesting their broad roles in caffeine metabolism. In this study, F1 strains of "Longjing43" ♂ × "Baihaozao" ♀ and different tea cultivars were used as materials to explore the correlation between caffeine content and gene expression. The heterologous expression systems of yeast and Arabidopsis were applied to explore the function of CsPUPs. Correlation analysis showed that the expressions of CsPUP1, CsPUP3.1, and CsPUP10.1 were significantly negatively correlated with caffeine content in tea leaves of eight strains and six cultivars. Furthermore, subcellular localization revealed that the three CsPUPs were not only located in plasma membrane but also widely distributed as circular organelles in cells. Functional complementation assays in yeast showed that the three CsPUPs could partly or completely rescue the defective function of fcy2 mutant in caffeine transport. Among them, transgenic yeast of CsPUP10.1 exhibited the strongest transport capacity for caffeine. Consistent phenotypes and functions were further identified in the CsPUP10.1-over-expression Arabidopsis lines. Taken together, it suggested that CsPUPs were involved in caffeine transport in tea plants. Potential roles of CsPUPs in the intracellular transport of caffeine among different subcellular organelles were proposed. This study provides a theoretical basis for further research on the PUP genes and new insights for caffeine metabolism in tea plants.

18.
Se Pu ; 39(5): 494-509, 2021 May.
Article in Chinese | MEDLINE | ID: mdl-34227334

ABSTRACT

QuEChERS pretreatment combined with gas chromatography-quadrupole time-of-flight mass spectrometry (GC-Q-TOF/MS) has been investigated for application in screening 244 pesticide residues in chilli. Fresh chilli samples were extracted with acetonitrile, and dried chilli samples were extracted using an acetonitrile/acetic acid (99∶1, v/v) mixture. The two extraction solvents were stored at -20 ℃. After salting out and cleaning by dispersive solid phase extraction (dSPE), heptachlor epoxide B was added as an internal standard, and the resulting residues were dissolved in 1.00 mL acetone. The dissolved sample solution was loaded onto an HP-5MS UI column (30 m×0.25 mm, 0.25 µm) and eluted by GC-Q-TOF/MS with a programmable temperature vaporizer and splitless injection in the full-scan mode. The compensation effects of the analytical protectant (AP) and matrix-matched calibration method on the matrix effect were established. AP could be used in the fresh chilli matrix to compensate for matrix effects, but it was not effective in the dried chilli matrix. The matrix-matched calibration method was effective in both matrices, which was selected for the quantification of pesticide residues in the samples. Because of the existence of the isomers of one compound and the same characteristic ions of different compounds, analyte detection was based on a flexible retention time deviation of ±0.25 min and accurate mass deviation of ±20×10 -6. Screening was performed by the software in the automatic matching mode. Compound identification and quantitation were based on a database and calibration curve established with reference materials. Suspicious samples were subjected to manual analysis. Quantitative analysis of 244 pesticide residues in fresh chilli and 222 pesticide residues in dried chilli was performed. The results showed that the developed database and method can provide a reference for the high-throughput screening and quantitation of fresh and dried chilli. Different levels of pesticides were added to the blank chilli samples, and the addition level corresponding to a signal-to-noise ratio (S/N) of 10 was used as the limit of quantification (LOQ). The LOQs of 44 pesticides with a maximum residue limit (MRL) ≤0.05 mg/kg in fresh chilli did not exceed 0.010 mg/kg. The linear ranges of these 44 pesticides were 0.01-1.00 mg/L. At spiked levels of the LOQ and 2.5 times the LOQ, the ratios of the 44 pesticides with recoveries of 60% to 120% were 88.64% and 100%, respectively. The LOQs of 200 pesticides with MRLs ≥0.05 mg/kg or without MRLs in fresh chilli did not exceed 0.025 mg/kg. The linear ranges of these 200 pesticides were 0.05-1.00. At spiked levels of the LOQ, twice the LOQ, and 10 times the LOQ, the ratios of the 200 pesticides with recoveries of 60% to 120% were 49.50%, 87.00%, and 89.50%, respectively. The linear correlation coefficients (r 2) of the 244 pesticides in fresh chilli were greater than 0.99. The LOQs of 222 pesticides in dried chilli were less than 0.15 mg/kg, and the linear ranges were 0.04-1.00 mg/L. The ratios of these 222 pesticides with r 2 greater than 0.99 was 95.46%. At spiked levels of the LOQ, twice the LOQ and 10 times the LOQ in dried chilli, the ratio of the 222 pesticides with recoveries of 60% to 120% were 72.52%, 73.42%, and 81.53%, respectively. The established screening and confirmation method was used to analyze 12 fresh chilli samples and 14 dried chilli samples. Eight pesticides were found in nine fresh chilli samples and three dried chilli samples, all of which were confirmed to be positive after manual identification. The concentrations of these pesticides were lower than the MRLs required by GB 2763-2019: National Food Safety Standard Maximum Residue Limits for Pesticides in Food. The results demonstrate that the established method is rapid, easy to execute, efficient, and reliable. It can be used for the high-throughput screening and quantitation of pesticide residues in fresh and dried chilli.


Subject(s)
Food Analysis/methods , Food Contamination/analysis , Pesticide Residues , Calibration , Gas Chromatography-Mass Spectrometry , Meat/analysis , Pesticide Residues/analysis , Solid Phase Extraction
19.
Aging Dis ; 11(1): 141-153, 2020 Feb.
Article in English | MEDLINE | ID: mdl-32010488

ABSTRACT

Diabetes mellitus (DM) is a chronic metabolic disease with high morbidity and mortality. Recently, stem cell-based therapy for DM has shown considerable promise. Here, we undertook a systematic review and meta-analysis of published clinical studies to evaluate the efficacy and safety of stem cell therapy for both type 1 DM (T1DM) and type 2 DM (T2DM). The PubMed, Cochrane Central Register of Controlled Trials, EMBASE, and ClinicalTrials.gov databases were searched up to November 2018. We employed a fixed-effect model using 95% confidence intervals (CIs) when no statistically significant heterogeneity existed. Otherwise, a random-effects statistical model was used. Twenty-one studies met our inclusion criteria: ten T1DM studies including 226 patients and eleven T2DM studies including 386 patients. Stem cell therapy improved C-peptide levels (mean difference (MD), 0.41; 95% CI, 0.06 to 0.76) and glycosylated hemoglobin (HbA1c; MD, -3.46; 95% CI, -6.01 to -0.91) for T1DM patients. For T2DM patients, stem cell therapy improved C-peptide levels (MD, 0.33; 95% CI, 0.07 to 0.59), HbA1c (MD, -0.87; 95% CI, -1.37 to -0.37) and insulin requirements (MD, -35.76; 95% CI, -40.47 to -31.04). However, there was no significant change in fasting plasma glucose levels (MD, -0.52; 95% CI, -1.38 to 0.34). Subgroup analyses showed significant HbA1c and C-peptide improvements in patients with T1DM treated with bone marrow hematopoietic stem cells (BM-HSCs), while there was no significant change in the mesenchymal stem cell (MSC) group. In T2DM, HbA1c and insulin requirements decreased significantly after MSC transplantation, and insulin requirements and C-peptide levels were significantly improved after bone marrow mononuclear cell (BM-MNC) treatment. Stem cell therapy is a relatively safe and effective method for selected individuals with DM. The data showed that BM-HSCs are superior to MSCs in the treatment of T1DM. In T2DM, MSC and BM-MNC transplantation showed favorable therapeutic effects.

20.
J Agric Food Chem ; 68(8): 2445-2456, 2020 Feb 26.
Article in English | MEDLINE | ID: mdl-31899627

ABSTRACT

Nitrogen (N) uptake, as the first step of N metabolism, is a key limiting factor for plant growth. To understand the gene expression networks that control N absorption and metabolism in tea plants, we analyzed transcriptomes in the young roots of two groups of tea plants with significantly different growth rates under different N treatments (0, 0.2, and 2 mM). Using pairwise comparisons and weighted gene co-expression network analyses (WGCNA), we successfully constructed 16 co-expression modules. Among them, a specific module (turquoise) that substantially responded to the low N treatment was identified. Based on KEGG analysis, the relative genes that enriched in the "N metabolism" pathways were used to construct gene co-expression networks of N metabolism. Finally, a high-affinity ammonium (NH4+) transporter designated CsAMT1.2 was identified as a hub gene in the N metabolism network in tea plant roots and the gene expression could be highly induced by N resupply. The gene functional analysis revealed that CsAMT1.2 could make functional complementation of MEP1, MEP2, and MEP3 genes in 31019b yeast cells and improve NH4+ uptake rate in 31019b at low NH4+ level. Thus, CsAMT1.2 was a key gene controlling N uptake in tea plants and might play a vital role in promoting NH4+ uptake from the environment in tea roots. This study provided a useful foundation for improving the NUE in tea plantations.


Subject(s)
Camellia sinensis/genetics , Camellia sinensis/metabolism , Nitrogen/metabolism , Plant Proteins/genetics , Biological Transport , Gene Expression Regulation, Plant , Gene Regulatory Networks , Plant Proteins/metabolism , Plant Roots/genetics , Plant Roots/metabolism , Transcriptome
SELECTION OF CITATIONS
SEARCH DETAIL
...