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1.
Animals (Basel) ; 12(9)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35565572

RESUMO

Kudoa (Myxosporea: Multivalvulida) parasites are critical pathogens in marine and freshwater fish associated with significant economic losses and reduced market prices caused by post-mortem myoliquefaction or numerous cysts on muscles. In the present study, large yellow croakers infected by Kudoa were found during fish disease surveillance in China in November 2020 and used for morphological observation and characterization using light DIC microscopy and electron microscopy. Numerous creamy-white oval plasmodia were observed in muscles and on the surface of brain cartilage, gill arches, and serosal surfaces. The spores were considerably longer and thicker than previously reported Kudoa, with protruding polar filaments (PFs) in the mature spores, fingertip-shaped apical projections (APs), and polar capsules. Phylogenetic analyses with SSU rDNA, LSU rDNA, and mitochondrial DNA showed that the Kudoa-infected sample (LcK-2020) had the highest similarity to Kudoa iwatai reported in Japan. Based on the morphological characterization and phylogenetic analysis, it could be concluded that the sample LcK-2020 was infected by Kudoa iwatai, which would be the first report of Kudoa iwatai infection in large yellow croaker in China.

2.
Anim Biotechnol ; : 1-10, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35167410

RESUMO

The purpose of this study was to explore the effects of Rice straw and King grass on apparent digestibility, ruminal bacterial, and fungus composition in buffaloes. Three ruminal fistulated buffaloes were used in a 3 × 2 Latin square design. The dietary treatments were king grass and straw hay. Experimental animals were kept in individual pens and concentrate was offered at 1 kg/d while roughage was fed ad libitum. Each period lasted for 15d, with the first 12d for an adaptation period, followed by a 3-day formal trial period. King grass has higher digestibility of protein. Rice straw has higher digestibility to cellulose. The results showed that when buffaloes were fed king grass and straw, Bacteroidetes were dominant in the rumen normal flora, but firmicutes were not. In addition, the results of this experiment suggest that increasing protein content in diets may be beneficial to increase the relative abundance of Proteobacteria. Similarly, higher dietary fiber content may be beneficial for increasing relative abundance of Prevotella and Staphylococcus. The dominant fungi in ruminal fluid 2 h after ingestion were aerobic fungi. These aerobic fungi most likely entered the rumen with food. Whether and how long aerobic fungi can survive in the rumen needs more research.

3.
Environ Res ; 208: 112735, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35051428

RESUMO

The low methanogenic efficiency of protein wastewater during anaerobic digestion can be attributed to the hydrolysis rate-limiting caused by the complex native structure of protein. In this study, the characterization of secondary structure alterations of protein molecules under acid-base stress was investigated and the effect of structure and conformation alterations on the methanogenic efficiency of protein wastewater biotransformation was analyzed. The optimal methane yields were obtained for protein wastewater pretreated with acid and base at pH = 3 and pH = 12, which was 29.4% and 35.7% higher than that of the control group (without pretreatment), reaching 142.6 ± 4.0 mL/g protein and 149.6 ± 16.1 mL/g protein, respectively. The time economy evaluation showed that 6 h pretreatment time was scientific and reasonable whether pH = 3 or pH = 12, since the methane gain effect reached 74.4% and 82.2% longing with the anaerobic digestion proceeded to 120 h, respectively. Endogenous fluorescence characteristics illustrated that the microenvironment of protein molecules has changed regardless of acid or alkali pretreatment. The circular dichroism (CD) analysis revealed that only the content of α-helix in the secondary structure of the protein at pH = 12 decreased by 46.3%, while the contents of ß-sheet, ß-turn and unordered structure were 29.5 ± 0.8%, 18.9 ± 0.6% and 32.2 ± 1.3%, respectively. The increase in the composition of the unordered structure demonstrated an irreversible damage to the hydrogen bonding network in the protein. FTIR spectroscopy further confirmed that the stretching vibrations of CO in amide I led to the destruction of the hydrogen bonding network and the unfolding of the protein structure. Thus, the above work provides new insights into the anaerobic digestion of protein wastewater for methanogenic processes from the perspective of protein structure and conformational changes.


Assuntos
Eliminação de Resíduos Líquidos , Águas Residuárias , Anaerobiose , Reatores Biológicos , Biotransformação , Ligação de Hidrogênio , Metano , Esgotos/química , Eliminação de Resíduos Líquidos/métodos
4.
J Laparoendosc Adv Surg Tech A ; 32(2): 158-164, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33651638

RESUMO

Objective: To investigate the efficacy and safety of cold snare endoscopic mucosal resection (CS-EMR) and hot snare endoscopic mucosal resection (HS-EMR) for colorectal polyps with diameters of 6-9 mm. Methods: Retrospective analysis was performed on the clinical data of 485 patients with colorectal polyps (6-9 mm in size) who were treated with CS-EMR or HS-EMR in the endoscopy center of Hangzhou Third People's Hospital from January 2017 to December 2019. Colorectal polyps were lifted by submucosal injection of normal saline. The CS-EMR group used a cold snare to remove the lifting polyps, while the HS-EMR group used a hot snare. Propensity score matching analysis with 1:1 matching and the nearest neighbor matching method were performed to ensure well-balanced characteristics of the CS-EMR and HS-EMR groups. Matching factors included age, gender, body mass index, blood routine, coagulation indicators, polyp site, size, number, and morphology. This resulted in a balanced cohort of 128 patients per group. Polyp recovery, complications, clipping for disclosure, and length of hospital stay were compared after matching. t-Tests, χ2 tests, McNemar's tests, and Fisher's exact test were used for comparison between the two groups before and after matching. Results: There were no differences between the two groups of intraoperative and postoperative bleeding (P > .05), but the CS-EMR clipping rate was lower than the HS-EMR group (P < .01). There was a higher incidence of post-polypectomy syndrome (PPS) (P = .03) and longer hospital stays (P < .01) in the HS-EMR group than the CS-EMR group. Conclusions: Compared with HS-EMR, CS-EMR is more convenient to operate, with a low incidence of PPS, clipping rates, and short hospital stays. It is a safe and effective removal method for 6-9 mm colorectal polyps.


Assuntos
Pólipos do Colo , Ressecção Endoscópica de Mucosa , Pólipos do Colo/cirurgia , Colonoscopia , Humanos , Pontuação de Propensão , Estudos Retrospectivos
5.
Environ Geochem Health ; 44(2): 301-318, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33761034

RESUMO

This study developed a method to build relationships between chemical fractionations of heavy metals in soils and their accumulations in rice and estimate the respective contribution of each geochemical speciation in the soils from the Yangtze River Delta, China. In contaminated areas, residue and humic acid-bound fractions in soils were the main phases for most heavy metals. The mobility of heavy metals was in this following order: Cd > Pb ≈ Zn > Ni > As ≈ Cr > Hg. Transfer factors calculated by the ratios of specific fractionations of heavy metals in the soil-rice system were used to assess the capability of different metal speciation transfer from soil to rice. The carbonate and Fe/Mn oxyhydroxides bound phase had significant positive correlations with total metal concentrations in rice. Hg uptake by rice might be related to the exchangeable and carbonate-bound fractions of soil Hg. Results of PCA analysis of transfer factors estimated that the labile fractions (i.e. water soluble, exchangeable and carbonate bound) contributed more than 40% of the heavy metal accumulations in rice. Effect of organic matter and residue fraction on metals transfer was estimated to be ~ 25 to ~ 30% while contribution of humic acid and Fe/Mn oxyhydroxides-bound fractions was estimated to be ~ 20 to ~ 30%. Modified risk assessment code (mRAC) and ecological contamination index (ECI) confirmed that the soil samples were polluted by heavy metals. Soil Cd contributed more than 80% of mRAC. Contrarily, the main contributors to ECI were identified as As, Hg, Pb and Zn. The average values of total target hazard quotient (TTHQ) and Risktotal were above 1 and 10-4 respectively, implying people living in the study area were exposed to both non-carcinogenic and carcinogenic risk. As and Pb were the main contributor to high TTHQ value while As, Cd and Cr in rice contributed mostly to Risktotal value. Spatial changes of ecological risk indexes and human health risk indexes showed that the samples with high TTHQ values distributed in the area with high values of mRAC. Likewise, the area with high ECI values and with high carcinogenic risk overlapped.


Assuntos
Metais Pesados , Oryza , Poluentes do Solo , Disponibilidade Biológica , Fracionamento Químico , China , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Medição de Risco , Solo/química , Poluentes do Solo/análise
6.
Asian J Androl ; 24(1): 5-14, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34135169

RESUMO

Continuous spermatogenesis depends on the self-renewal and differentiation of spermatogonial stem cells (SSCs). SSCs, the only male reproductive stem cells that transmit genetic material to subsequent generations, possess an inherent self-renewal ability, which allows the maintenance of a steady stem cell pool. SSCs eventually differentiate to produce sperm. However, in an in vitro culture system, SSCs can be induced to differentiate into various types of germ cells. Rodent SSCs are well defined, and a culture system has been successfully established for them. In contrast, available information on the biomolecular markers and a culture system for livestock SSCs is limited. This review summarizes the existing knowledge and research progress regarding mammalian SSCs to determine the mammalian spermatogenic process, the biology and niche of SSCs, the isolation and culture systems of SSCs, and the biomolecular markers and identification of SSCs. This information can be used for the effective utilization of SSCs in reproductive technologies for large livestock animals, enhancement of human male fertility, reproductive medicine, and protection of endangered species.


Assuntos
Células-Tronco Germinativas Adultas , Espermatogônias , Animais , Diferenciação Celular , Masculino , Espermatogênese , Células-Tronco
7.
Cardiovasc Intervent Radiol ; 45(4): 488-501, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34282489

RESUMO

PURPOSE: To evaluate the effectiveness and safety of prophylactic intraoperative uterine artery embolization (UAE) performed immediately after fetal delivery during planned cesarean section or cesarean hysterectomy in patients with placenta accreta spectrum disorder or placenta previa. METHODS: A systematic search was conducted on Ovid MEDLINE and Embase, PubMed, Web of Science, and Cochrane databases. Studies were selected using the Population/Intervention/Comparison/Outcomes (PICO) strategy. The intraoperative blood loss and the rate of emergent peripartum hysterectomy (EPH) were the primary outcomes, whereas the length of hospital stay and volume of blood transfused were the secondary outcomes. A random-effects model was employed to pool each effect size. The cumulative values of the primary outcomes were calculated using the generic inverse variance method. RESULTS: Eleven retrospective cohort studies and five case series were included, recruiting 421 women who underwent prophylactic intraoperative UAE (UAE group) and 374 women who did not (control group). Compared with the control group, the UAE group had significantly reduced intraoperative blood loss (p = 0.020) during cesarean section or cesarean hysterectomy. Furthermore, the EPH rate was also significantly decreased (p = 0.020; cumulative rate: 19.65%), but not the length of hospital stay (p = 0.850) and volume of pRBC transfused (p = 0.140), after cesarean section in the UAE group. The incidence of major complications was low (3.33%), despite two patients with uterine necrosis. CONCLUSION: The currently available data provides encouraging evidence that prophylactic intraoperative UAE may contribute to hemorrhage control and fertility preservation in women with abnormal placentation. REGISTRATION: PROSPERO registration code: CRD42021230581. https://clinicaltrials.gov/ct2/show/CRD42021230581 LEVEL OF EVIDENCE: Level 2a, systematic review of retrospective cohort studies.


Assuntos
Placenta Acreta , Placenta Prévia , Hemorragia Pós-Parto , Embolização da Artéria Uterina , Cesárea/métodos , Feminino , Humanos , Histerectomia , Placenta Acreta/cirurgia , Placenta Prévia/cirurgia , Placentação , Hemorragia Pós-Parto/prevenção & controle , Gravidez , Estudos Retrospectivos , Embolização da Artéria Uterina/métodos
8.
Chemosphere ; 287(Pt 1): 131932, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34455122

RESUMO

Efficient elimination of fluoride from wastewater is an urgent need for ensuring water safety. In the present study, a stable and reusable nanocomposite (NCO@PAE) was synthesized by impregnating nanosized cerium oxides (NCO) inside a porous polystyrene anion exchanger (PAE) host for efficient fluoride removal from wastewater. The newly fabricated NCO@PAE exhibited excellent resistance to acid and alkali environment, allowing it to be utilized in a wide pH range (2-12). Fluoride uptake onto NCO@PAE was a pH-dependent process, which could reach the maximum capacity at pH 3.0. Compared with its host PAE, NCO@PAE showed conspicuous adsorption affinity towards fluoride in the coexistence of other competing anions at high concentrations. Adsorption kinetics confirmed its high efficiency for achieving equilibrium within 120 min. Fixed-bed adsorption runs demonstrated that the effective processing capacity of NCO@PAE for synthetic fluoride-containing wastewater (initial fluoride 2.5 mg/L) was about ~330 BV (bed volume), while only 22 BV for the host PAE. The exhausted NCO@PAE could be effectively revived by a simple in-situ desorption method for long-term cycle operation without conspicuous capacity loss. All the results indicated that NCO@PAE is a reliable and promising adsorbent for water defluoridation.


Assuntos
Cério , Poluentes Químicos da Água , Purificação da Água , Adsorção , Ânions , Fluoretos , Concentração de Íons de Hidrogênio , Cinética , Poliestirenos , Porosidade , Água , Poluentes Químicos da Água/análise
9.
Environ Sci Technol ; 56(1): 194-207, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34935353

RESUMO

In recent years, dozens of halogenated disinfection byproducts (DBPs) with cyclic structures were identified and detected in drinking water globally. Previous in vivo toxicity studies have shown that a few new cyclic DBPs possessed higher developmental toxicity and growth inhibition rate than common aliphatic DBPs; however, in vitro toxicity studies have proved that the latter exhibited higher cytotoxicity and genotoxicity than the former. Thus, to provide a more comprehensive toxicity comparison of DBPs from different endpoints, 11 groups of cyclic DBPs and nine groups of aliphatic DBPs were evaluated for their comparative in vitro and in vivo toxicity using human hepatoma cells (Hep G2) and zebrafish embryos. Notably, results showed that the in vitro Hep G2 cytotoxicity index of the aliphatic DBPs was nearly eight times higher than that of the cyclic DBPs, whereas the in vivo zebrafish embryo developmental/acute toxicity indexes of the cyclic DBPs were roughly 48-50 times higher than those of the aliphatic DBPs, indicating that the toxicity rank order differed when different endpoints were applied. For a broader comparison, a Pearson correlation analysis of DBP toxicity data from nine different endpoints was conducted. It was found that the observed Hep G2 cytotoxicity and zebrafish embryo developmental/acute toxicity in this study were highly correlated with the previously reported in vitro CHO cytotoxicity and in vivo toxicity in aquatic organisms (P < 0.01), respectively. However, the observed in vitro toxicity had no correlation with the in vivo toxicity (P > 0.05), suggesting that the toxicity rank orders obtained from in vitro and in vivo bioassays had large discrepancies. According to the observed toxicity data in this study and the candidate descriptors, two quantitative structure-activity relationship (QSAR) models were established, which help to further interpret the toxicity mechanisms of DBPs from different endpoints.


Assuntos
Desinfetantes , Água Potável , Poluentes Químicos da Água , Purificação da Água , Animais , Desinfetantes/toxicidade , Desinfecção , Água Potável/química , Halogenação , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Peixe-Zebra
10.
Front Psychol ; 13: 805208, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35369191

RESUMO

Based on social exchange theory and attribution theory, this paper explores the role of affective commitment and organizational support in the relationship between career growth and the engagement of knowledge workers. The results show that (1) career growth has a positive impact on knowledge workers' organizational engagement; (2) career goal progress and professional ability development promote job engagement; (3) career growth has a positive effect on affective commitment, which in turn influences employee engagement; (4) affective commitment plays a mediating role in the effect of career growth on engagement; and (5) perceived organizational support positively moderates the relationship between career growth and affective commitment.

11.
Animals (Basel) ; 11(11)2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34827747

RESUMO

Enterocytozoon bieneusi is a fungus-like protist parasite that can cause diarrhea and enteric diseases. The infection of E. bieneusi has been reported in many host species, including cattle and humans. However, information on prevalence and genotype distribution of E. bieneusi in dairy cattle in Yunnan province in China is still absent. In this study, 490 Holstein Cows and 351 dairy buffalo fecal samples were collected from three regions in Yunnan province, China. By using nest-PCR that targets the internal transcribed spacer (ITS), we found that the prevalence of E. bieneusi was 0.59% (5/841). DNA sequence analysis showed that five E. bieneusi genotypes were identified in this study, including two novel genotypes, YNDCEB-90 and YNDCEB-174, and three known genotypes (I, J, BEB4). Phylogenetic analysis revealed that two novel genotypes, YNDCEB-90 and YNDCEB-174, were clustered into Group 1, representing the zoonotic potential. The remaining genotypes I, J, and BEB4, which are the most frequent genotypes of E. bieneusi infection in cattle and lead to E. bieneusi infection in humans, belonged to Group 2. Although the lower prevalence of E. bieneusi was detected in dairy cattle in Yunnan province, it indicates that dairy cattle should be considered to be one of the potential hosts for transmitting E. bieneusi to humans. These findings are important for the development of effective prevention strategies for microsporidiosis.

13.
Huan Jing Ke Xue ; 42(8): 3622-3632, 2021 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-34309249

RESUMO

In recent years, China's air quality has been improving, and the concentration of atmospheric particulate matter has decreased significantly. In this study, the pollution characteristics and trends of two typical representative cities (Beijing and Chengdu) were analyzed. The geographical locations, pollution emissions, and meteorological diffusion conditions of the two cities were compared, to evaluate the relative contribution of meteorological conditions and pollution reduction regulations in decreasing fine particulate matter (PM2.5) concentrations. The results showed that the number of heavily polluted days and pollution episodes in Beijing and Chengdu decreased significantly from 2013 to 2018, and the concentration of SO2 and PM2.5 decreased substantially. Compared to 2013, SO2 concentration in Beijing and Chengdu has decreased by 77.8% and 70.9%, whereas PM2.5 concentration has decreased by 42.7% and 48.5%, respectively. The largest reduction appeared in winter, when PM2.5 decreased at an annual rate of 13.5 µg ·m-3 for Beijing and 14.1 µg ·m-3 for Chengdu. During the study period, the wind speed in Chengdu was less than that in Beijing, temperature was approximately 3℃ higher, and static wind in winter was more frequent. A significantly lower mixed-layer height, atmospheric capacity index, and ventilation coefficient in Chengdu resulted in more unfavorable atmospheric diffusion conditions. The static and stable weather index and the environmental meteorological index (EMI) also showed that the atmospheric diffusion conditions were better in Beijing than in Chengdu. The EMI of the two cities showed a decreasing trend during the study period, and the decline in EMI in Chengdu was the most significant in 2018, indicating an evident improvement in meteorological conditions. In 2018, emission reductions are estimated to have contributed 33.5% and 24% to the decrease in PM2.5 in Beijing and Chengdu, respectively, and meteorological conditions contributed 7.2% and 11.1% to the reduction in these two cities. In winter, emission reductions respectively contributed 31.7% and 32.5% to reduction in Beijing and Chengdu, while meteorological conditions made a larger contribution.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Pequim , China , Cidades , Monitoramento Ambiental , Material Particulado/análise , Melhoria de Qualidade , Estações do Ano
14.
J Orthop ; 25: 230-236, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34099952

RESUMO

INTRODUCTION: It is difficult to determine the optimal size of unicompartmental knee arthroplasty (UKA) prosthesis both pre-operatively and intra-operatively. Inappropriate femoral and tibial components are still the leading cause of failure. Several guidelines based on the Western population may not apply to the Chinese patients. We consequently try to investigate distributions of Oxford-UKA prosthesis in Chinese patients in order to provide a good reference for surgeons preoperatively. METHODS: From January 2010 to December 2019, 1909 patients (2307 knees) with primary anteromedial osteoarthritis accepted Oxford phase III UKA. Statistical analyses were performed on the distributions of the femoral, tibial, and matching of the femoral-tibial prosthesis. The possible factors affecting the sizes of femoral components, including gender, height based on gender were investigated. RESULTS: 1. The distributions of femoral size components include extra-large (XL) 0, large (L) 1.08%, medium (M) 26.09%, small (S) 59.64%, extra-small (XS) 13.18%; the tibial sizes components were F 0, E 0.69%, D 7.80%, C 19.59%, B 24.79%, A 34.16%, AA 12.96%. 2. The matching of femur-tibia components were L-E 0.52%,L-D 0.52%,M-E 0.17%, M-D 7.28%,M - C 16.60%,M - B 1.95%,M-A 0.13%, M-AA 0.04%, S-C 2.99%, S-B 22.67%, S-A 31.12%, S-AA 2.82%, XS-B 0.17%, XS-A 2.90% and XS-AA 10.10%. The optimal matches between femoral and tibial components were: XL with F; L with E; M with C and D; S with A and B. 3. The patient's gender and height based on gender are necessary considerations for selection of femoral components (P<0.01). CONCLUSION: In Chinese patients, the size of femoral components is mainly small (S) for women, medium (M) for men. The tibial components of female patients are mainly A and B, whereas C is predominant for male patients. The more commonly used matching forms are S-A and S-B.

15.
Artigo em Inglês | MEDLINE | ID: mdl-33982301

RESUMO

BACKGROUND AND AIM: An accurate assessment of liver fibrosis is critical for the management of chronic hepatitis B (CHB) patients. Two-dimensional shear wave elastography (2D-SWE) and magnetic resonance elastography (MRE) have recently been proposed to diagnose liver fibrosis. To determine the optimal noninvasive method for diagnosing fibrosis in CHB, we conducted a meta-analysis to compare the performance of 2D-SWE and MRE for diagnosing fibrosis in patients with CHB. METHODS: Literature databases were searched until January 1st 2021. Three measures, the summary area under the receiver operating characteristic curve (AUSROC), the summary diagnostic odds ratios, and the summary sensitivities and specificities, were used to assess the performance of 2D-SWE and MRE for detecting liver fibrosis. RESULTS: Twenty-four studies with 5126 CHB patients were included. The summary sensitivities and specificities of 2D-SWE and MRE were 82% and 81%, 91% and 94%, respectively, for detecting significant fibrosis, 88% and 85%, 93% and 93%, respectively, for detecting advanced fibrosis, and 89% and 87%, 92% and 92%, respectively, for detecting cirrhosis. The AUSROC value of MRE (0.97) in predicting significant fibrosis was significantly higher than those of 2D-SWE (0.88, P < 0.001). The AUSROC values of 2D-SWE and MRE were 0.93 and 0.98, respectively, for the diagnosis of advanced fibrosis, and 0.94 and 0.97, respectively, for the diagnosis of cirrhosis. CONCLUSIONS: MRE and 2D-SWE are excellent tools for staging fibrosis in patients with CHB. MRE probably exhibit the better diagnostic accuracy in detecting significant fibrosis as compared to 2D-SWE.

16.
Microsc Res Tech ; 84(9): 2095-2103, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33934435

RESUMO

Chestnut rose, R. roxburghii Tratt. (Rosaceae) (RR) is an important crop in China due to its nutritional and medicinal values. RR frequently produces trichomes on the surfaces of a diverse range of organs, however a genetic component exists to the control of trichome development, with some cultivars having significantly fewer trichomes to others. Certain varieties have fruits that are thickly covered with macroscopic trichomes, which is an undesirable trait for fruit processing and consumption. However, smooth-fruit cultivars exist, such as R. roxburghii Tratt. f. esetosa Ku (RRE). Despite their economic importance, the anatomical features of trichomes have not been explored in detail for these two chestnut rose germplasms. Here, we investigate the ultrastructure of trichomes distributed on the stem, sepal, and fruit of RR and RRE using transmission electron microscopy (TEM). The internal structure of stem prickle trichomes in RR and RRE was oval in shape and did not contain nucleoli or other organelles. The cell walls of stem prickles in RR are thick and the intercellular spaces occupied with liquid, whereas the cells wall of stem prickles in RRE are thin and have air-filled intercellular spaces. The cells of sepal acicular trichomes in RR and glandular trichomes (GTs) of sepals in RRE had similar vacuole sizes, cytoplasm content, intercellular spaces, and arrangement of plastids within cells. However, there were osmiophilic granules present in the GTs of RRE. The flagelliform trichomes in the sepals of the two germplasms are composed of oval or rod-shaped cells. Although the flagelliform trichomes in the sepals of the two germplasms had a similar internal structure, and both contained starch grains and plastids with visible thylakoid membranes, the flagelliform trichomes in the sepals of RR had a thinner cell wall and a higher proportion of cytoplasm which was more evenly distributed across the cell. There were granules that stained heavily with osmium tetroxide which occurred infrequently in the flagelliform trichomes of sepals in RRE but were not observed in RR. On the acicular trichomes of fruit in RR, the flagelliform trichomes and the GTs of fruit in RRE shared similar cell morphology, arrangement and vacuole size as well as intercellular space. Both the fruit flagelliform trichomes and GTs in RRE contain granules which stain heavily with osmium tetroxide, and the GTs contain plastids and starch grains. These differences in trichome cell ultrastructure may be related to developmental processes or biological functions of the trichomes. These results also suggest that the two chestnut rose germplasms are good candidates for further study of trichome ontogeny in the genus and subsequent breeding of the smooth organ trait in this species.


Assuntos
Rosa , China , Frutas , Fenótipo , Tricomas
17.
Talanta ; 229: 122223, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33838765

RESUMO

Short-chain fatty alcohols (SCFAs) are one of the reactants for the production of biodiesels. The SCFA residues at the trace level have a significant impact on biodiesel quality. However, the analysis of SCFAs in aged biodiesels has not been reported so far, which is probably due to the unavailability of an appropriate analytical method for the simultaneous determination of SCFAs. Herein, we developed a novel analytical approach with high sensitivity and selectivity for the simultaneous identification and determination of SCFAs in seed oil and biodiesel samples during the simulated real-time aging by stable isotope labeling assisted liquid chromatography-mass spectrometry (SIL-LC-MS). A pair of isotope labeling reagents, pyridine (Py) and [2H5]pyridine ([2H5]Py), were used to label SCFAs in biodiesels and standards, respectively. The [2H5]Py labeled SCFAs were used as internal standards to compensate for the detection of variances. The simultaneous determination of SCFAs was performed by LC-MS with an improved detection selectivity and sensitivity. The limits of detection (LODs) values were ranged from 0.2 to 0.5 ng mL-1 for the investigated SCFAs. Good linearity was observed in the studied ranges (R2 > 0.99) and good precision with relative standard deviations (RSDs) was in the range of 4.9-18.1%. Average recoveries were obtained in the range of 80.3%-115.4%. The matrix effects were in the range of 70.0-104.3%. The validated SIL-LC-MS method was applied to the simultaneous quantitative analysis of SCFAs in seed oil and biodiesel samples and the LC-MS analysis could be done within 3 min. The formation mechanism of SCFAs in aged oil and biodiesel samples was also investigated by this method. The results suggest that SCFAs were formed and their composition changed during the simulated real-time aging of long-chain fatty acid (LCFA), long-chain fatty acid methyl ester (FAME), seed oil, and biodiesels. Moreover, we found that the formation of 1-pentanol and 1-hexanol was associated with the number and position of double bonds in LCFAs and FAMEs.

18.
Environ Sci Pollut Res Int ; 28(33): 45109-45120, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33864217

RESUMO

Sewage treatment is an important public service, but it consumes a lot of energy and chemicals in the process of removing wastewater pollutants, which may cause the risk of pollution transfer. To find the corresponding hot issues, this paper took the lead in integrating life cycle assessment (LCA) with life cycle costing (LCC) to evaluate four most typical sewage treatment technologies with more than 85% share in China. It is found that anaerobic/anoxic/oxic (AAO) was the optimal treatment scheme with relatively small potential environmental impact and economic load. The normalized results show that the trends of the four technologies on eleven environmental impact categories were basically the same. Marine aquatic ecotoxicity potential accounted for more than 70% of the overall environmental impact. Contribution analysis indicates that electricity and flocculant consumption were the main processes responsible for the environmental and economic burden. Overall, electricity consumption was the biggest hot spot. Sensitivity analysis verifies that a 10% reduction in electricity could bring high benefits to both the economy and the environment. These findings are expected to provide effective feedback on the operation and improvement of sewage treatment. Graphical abstract.


Assuntos
Esgotos , Águas Residuárias , Animais , China , Meio Ambiente , Estágios do Ciclo de Vida , Eliminação de Resíduos Líquidos
19.
Anal Chim Acta ; 1158: 338402, 2021 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-33863407

RESUMO

Chemical derivatization-assisted electrospray ionization-triple quadrupole mass spectrometry (ESI-QqQ-MS) has become an efficient tool for the quantification of low-molecular-weight molecules. Many studies found that the derivatives of the same analytes derivatized by different derivatization reagents with the same reaction group had different detection sensitivity, even under the same conditions of electrospray ionization-mass spectrometry (ESI-MS). This phenomenon was suggested to be caused by the different modifying groups in the derivatization reagents. However, there is still a lack of systematic study on how modifying groups in the derivatization reagents affect the detection sensitivity of their corresponding derivatives of analytes, especially theoretical investigations. In this study, we employed a quantitative structure-activity relationship (QSAR) modeling approach to explore the relationship between modifying group structures and the detection sensitivity of derivatization reagents and their derivatives during ESI-MS detection. A total of 110 derivatization reagents of the hydrazine family and their hexanal derivatives (substituted hydrazones) were selected as the prototypes to construct QSAR models. The established models suggested that several molecular descriptors, related to hydrophobicity, electronegativity, and molecular shape, were related to the detection sensitivity of hexanal derivatives induced by different modifying groups in the derivatization reagents. Besides, we found that the detection sensitivity of compounds detected in selected ion mode (SIM) showed a positive correlation with that obtained in multiple reaction monitoring mode (MRM), and the ionization efficiency was the key factor on the detection sensitivity in both modes.

20.
Talanta ; 226: 122107, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33676663

RESUMO

The free fatty acids that contain one to eight carbons (C1-C8) in biodiesel would affect the quality of biodiesel. It is still a matter of challenge to simultaneously determine the composition of C1-C8 fatty acids in seed oil and seed oil-based biodiesel. Herein, a novel method of charge derivatization coupling with direct infusion mass spectrometry (CD-DIMS) was developed for the determination of the C1-C8 fatty acids in biodiesels. A fixed-charge derivatization reagent, 1-cyclohexyl-3-(2-morpholinoethyl)carbodiimide (CMCT), was used to convert fatty acids into their cationic derivatives, which significantly improved the sensitivity and selectivity of detection. Good linearity was observed with the limits of detection (LODs) in the range of 0.0002-0.001 µg mL-1 for the investigated fatty acids. The recovery was in the range of 85.1%-101.9% and the matrix effect was within the range of 75.5-93.2%. The developed method was carried out to analyze C1-C8 fatty acids in rubber seed oil (RSO) and RSO-based biodiesels produced by different catalysts, including NaOH, TiO2, and carbodiimide. It was also applied to the dynamic monitoring of C1-C8 fatty acids in RSO and produced RSO biodiesels during the oxidation process. As results, formic acid, acetic acid, and propionic acid were detected in aged RSO and biodiesel samples. The contents of formic acid, acetic acid, and propionic acid all increased in aged RSO and biodiesels, but with different growth rates. These results demonstrated that the developed CD-DIMS method can provide a quick, accurate, and sensitive analysis of C1-C8 fatty acids in seed oil and biodiesel samples.

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