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BACKGROUND: Radical surgery remains the primary option for locally recurrent rectal cancer (LRRC) as it has the potential to considerably extend the patient's lifespan. At present, the effectiveness of laparoscopic surgery for LRRC remains unclear. METHODS: The clinical data of patients with LRRC who were admitted to the Cancer Hospital of the Chinese Academy of Medical Sciences between 2015 and 2021 were retrospectively analyzed in this study. Patients were categorized into two groups, namely the open group and the laparoscopic group, based on the surgical method used. Propensity score matching was used to reduce baseline differences. The short-term outcomes and long-term survival between the two groups were compared. RESULTS: Curative surgery was performed on 111 patients who were diagnosed with LRRC. After propensity score matching, a total of 80 patients were included and divided into the laparoscopic group (40 patients) and the open group (40 patients). The laparoscopic group had less intraoperative bleeding (100 vs. 300, P = 0.011), a lower postoperative complication rate (20.0% vs. 42.5%, P = 0.030), a lower incidence of wound infection (0 vs. 15.0%, P = 0.026), and a shorter time to first flatus (2 vs. 3, P = 0.005). The laparoscopic group had higher 3-year overall survival (85.4% vs. 57.5%, P = 0.016) and 3-year disease-free survival (63.9% vs 36.5%, P = 0.029). CONCLUSIONS: In comparison to open surgery, laparoscopic surgery is linked to less bleeding during the operation, quicker recovery after the surgery, and a lower incidence of infections at the surgical site. Moreover, laparoscopic surgery for LRRC might yield superior long-term survival outcomes.
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Laparoscopia , Recidiva Local de Neoplasia , Pontuação de Propensão , Neoplasias Retais , Humanos , Neoplasias Retais/cirurgia , Neoplasias Retais/mortalidade , Laparoscopia/métodos , Laparoscopia/estatística & dados numéricos , Laparoscopia/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Recidiva Local de Neoplasia/cirurgia , Resultado do Tratamento , Idoso , Fatores de Tempo , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Perda Sanguínea Cirúrgica/estatística & dados numéricos , AdultoRESUMO
BACKGROUND: In this study, we aimed to identify the risk factors in patients with rectal anastomotic re-leakage and develop a prediction model to predict the probability of rectal anastomotic re-leakage after stoma closure. METHODS: This study was a single-center retrospective analysis of patients with rectal cancer who underwent surgery between January 2010 and December 2020. Among 3225 patients who underwent Total or Partial Mesorectal Excision (TME/PME) surgery for rectal cancer, 129 who experienced anastomotic leakage following stoma closure were enrolled. Risk factors for rectal anastomotic re-leakage were analyzed, and a prediction model was established for rectal anastomotic re-leakage. RESULTS: Anastomotic re-leakage after stoma closure developed in 13.2% (17/129) of patients. Multivariable analysis revealed that neoadjuvant chemoradiotherapy (odds ratio, 4.07; 95% confidence interval, 1.17-14.21; p = 0.03), blood loss > 50 ml (odds ratio, 4.52; 95% confidence interval, 1.31-15.63; p = 0.02), and intersphincteric resection (intersphincteric resection vs. low anterior resection: odds ratio, 6.85; 95% confidence interval, 2.01-23.36; p = 0.002) were independent risk factors for anastomotic re-leakage. A nomogram was constructed to predict the probability of anastomotic re-leakage, with an area under the receiver operating characteristic curve of 0.828 in the cohort. Predictive results correlated with the actual results according to the calibration curve. CONCLUSIONS: Neoadjuvant chemoradiotherapy, blood loss > 50 ml, and intersphincteric resection are independent risk factors for anastomotic re-leakage following stoma closure. The nomogram can help surgeons identify patients at a higher risk of rectal anastomotic re-leakage.
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Fístula Anastomótica , Nomogramas , Neoplasias Retais , Estomas Cirúrgicos , Humanos , Estudos Retrospectivos , Feminino , Masculino , Fístula Anastomótica/etiologia , Pessoa de Meia-Idade , Neoplasias Retais/cirurgia , Estomas Cirúrgicos/efeitos adversos , Fatores de Risco , Idoso , Reto/cirurgia , Anastomose Cirúrgica/efeitos adversos , Adulto , Terapia Neoadjuvante/efeitos adversosRESUMO
The main type of saponins occurring in the root of Platycodon grandiflorus (Jacq.) A. DC. are oleanolic acid glycosides. The CYP716 gene family plays a major role in catalyzing the conversion of ß-amyrin into oleanolic acid. However, studies on the CYP716 genes in P. grandiflorus are limited, and its evolutionary history remains poorly understood. In this study, 22 PgCYP716 genes were identified, distributed among seven subfamilies. Cis-acting elements of the PgCYP716 promoters were mainly involved in plant hormone regulation and responses to abiotic stresses. PgCYP716A264, PgCYP716A391, PgCYP716A291, and PgCYP716BWv3 genes were upregulated in the root and during saponin accumulation, as shown by RNA-seq analysis, suggesting that these four genes play an important role in saponin synthesis. The results of subcellular localization indicated that these four genes encoded membrane proteins. Furthermore, the catalytic activity of these four genes was proved in the yeast, which catalyzed the conversion of ß-amyrin into oleanolic acid. We found that the content of ß-amyrin, platycodin D, platycoside E, platycodin D3, and total saponins increased significantly when either of the four genes was over expressed in the transgenic hair root. In addition, the expression of PgSS, PgGPPS2, PgHMGS, and PgSE was also upregulated while these four genes were overexpressed. These data support that these four PgCYP716 enzymes oxidize ß-amyrin to produce oleanolic acid, ultimately promoting saponin accumulation by activating the expression of upstream pathway genes. Our results enhanced the understanding of the functional variation among the PgCYP716 gene family involved in triterpenoid biosynthesis and provided a theoretical foundation for improving saponin content and enriching the saponin biosynthetic pathway in P. grandiflorus.
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Platycodon grandiflorus (Jacq.) A. DC, known for its saponin content, can potentially prevent and treat cerebrovascular diseases and COVID-19. Triterpenoid saponin biosynthesis in plants is enhanced by methyl jasmonate (MeJA) application. However, the underlying molecular mechanisms of MeJA-induced saponin biosynthesis remain unknown in P. grandiflorus. In the current study, exogenous application of 100 µmol/l MeJA was identified to be optimal for promoting saponin accumulation. RNA sequencing analysis demonstrated the PgbHLH28 gene as a key regulatory factor responding to MeJA during saponin accumulation. Overexpression of PgbHLH28 in P. grandiflorus increased saponin content, while silencing of PgbHLH28 significantly inhibited saponin synthesis, suggesting that PgbHLH28 acts as a positive regulator of saponin biosynthesis. Yeast one-hybrid and dual luciferase assays demonstrated that PgbHLH28 directly bound to the promoters of PgHMGR2 and PgDXS2 to activate gene expression. PgHMGR2 and PgDXS2 transformation promoted saponin accumulation, while silencing of these genes inhibited saponin biosynthesis. This study determined that MeJA promoted saponin accumulation in P. grandiflorus by inducing PgbHLH28 gene expression and activating downstream genes (PgHMGR2 and PgDXS2) involved in saponin biosynthesis. In conclusion, a complex regulatory network governing saponin biosynthesis following MeJA treatment was elucidated, offering a theoretical foundation for enhancing saponin content and biosynthesis efficacy in P. grandiflorus.
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PURPOSE: Surgical techniques and the prognosis of posterior pelvic exenteration for locally advanced primary rectal cancer in female patients pose challenges that need to be addressed. Therefore, we investigated the short-term and survival outcomes of posterior pelvic exenteration in female patients using a novel Peking classification. METHODS: We retrospectively analysed a prospective database from China PelvEx Collaborative across three tertiary referral centres. A total of 172 patients who underwent combined resection for locally advanced primary rectal cancer were classified based on four subtypes (PPE-I [64/172], PPE-II [68/172], PPE-III [21/172], and PPE-IV [19/172]) according to the Peking classification; perioperative characteristics and short-term and oncological outcomes were analysed. RESULTS: Differences were significant among the four groups regarding colorectal reconstruction (p < 0.001), perineal reconstruction (p < 0.001), in-hospital complications (p < 0.05), and urinary retention (p < 0.05). The R0 resection rates for PPE-I, PPE-II, PPE-III, and PPE-IV were 90.6%, 89.7%, 90.5%, and 89.5%, respectively. The 5-year overall survival rates of the PPE-I, PPE-II, PPE-III, and PPE-IV groups were 73.4%, 68.8%, 54.7%, and 37.3%, respectively. Correspondingly, their 5-year disease-free survival rates were 76.0%, 62.5%, 57.7%, and 43.1%, respectively. Notably, the PPE-IV group demonstrated the lowest 5-year overall survival rate (p < 0.001) and 5-year disease-free survival rate (p < 0.001). CONCLUSION: The Peking classification can aid in determining suitable surgical techniques and conducting prognostic assessments in female patients with locally advanced primary rectal cancer.
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Exenteração Pélvica , Neoplasias Retais , Humanos , Feminino , Neoplasias Retais/cirurgia , Neoplasias Retais/patologia , Estudos Retrospectivos , Pessoa de Meia-Idade , Prognóstico , China , Idoso , Estadiamento de Neoplasias , Resultado do Tratamento , Adulto , Intervalo Livre de DoençaRESUMO
Excess copper (Cu) imparts negative effects on plant growth and productivity in soil. To develop the ability of O. biennis to govern pollution soil containing excessive Cu, we investigated seed germination, seedling growth, and seed yield. Furthermore, Cu content and the expression levels of Cu transport related genes in different tissues were measured under exogenous high concentration Cu. O. biennis seeds were sensitive to excess Cu, with an observed reduction in the germination rate, primary root length, fresh weight, and number of seeds germinated daily. Consecutive Cu stress did not cause fatal damage to evening primrose, yet it slowed down plant growth slightly by reducing the leaf water, chlorophyll, plant yield, and seed oil contents while increasing the soluble sugar, proline, malondialdehyde, and H2O2 contents. The Cu content in different organs of O. biennis was disrupted by excess Cu. In particular, the Cu content in O. biennis seeds and seed oil increased and subsequently decreased with the increase of exogenous Cu, reaching a peak under 600â¯mg·kg-1 consecutive Cu. Furthermore, the 4-month 900â¯mg·kg-1 Cu treatment did not induce the excessive accumulation of Cu in peels, seeds, and seed oil, maintaining the Cu content within the range required by the Chinese National Food Safety Standards. The treatment also resulted in an upregulation of Cu-uptake (ObCOPT5, ObZIP4, and ObYSL2) and vigorous efflux (ObHMA1) of transport genes, of which expression levels were significant positive correlation (p < 0.05) with the Cu content. Among all organs, the stem replaced the root as the organ exhibited the greatest ability to absorb and store Cu, and even the Cu transport genes could still function continuously in stem under excess Cu. This work identified a species that can tolerate high Cu content in soil while maintaining a high yield. Furthermore, the results revealed the enrichment of Cu to occur primarily in the O. biennis stem rather than the seeds and peel under excess Cu.
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Cobre , Germinação , Oenothera biennis , Sementes , Poluentes do Solo , Poluentes do Solo/toxicidade , Cobre/toxicidade , Sementes/efeitos dos fármacos , Germinação/efeitos dos fármacos , Oenothera biennis/efeitos dos fármacos , Oenothera biennis/genética , Solo/química , Plântula/efeitos dos fármacosRESUMO
Sugars act as the main energy sources in many fruit and vegetable crops. The biosynthesis and transportation of sugars are crucial and especially contribute to growth and development. SWEET is an important gene family that plays a vital role in plants' growth, development, and adaptation to various types of stresses (biotic and abiotic). Although SWEET genes have been identified in numerous plant species, there is no information on SWEETs in Potentilla anserina. In the present study, we performed a comprehensive genome-wide bioinformatics analysis and identified a total of 23 candidate PaSWEETs genes in the Potentilla anserina genome, which were randomly distributed on ten different chromosomes. The phylogenetic analysis, chromosomal location, gene structure, specific cis-elements, protein interaction network, and physiological characteristics of these genes were systematically examined. The identified results of the phylogenetic relationship with Arabidopsis thaliana revealed that these PaSWEET genes were divided into four clades (I, II, III, and IV). Moreover, tissue-specific gene expression through quantitative real-time polymerase chain reaction (qRT-PCR) validation exposed that the identified PaSWEETs were differentially expressed in various tissues (roots, stems, leaves, and flowers). Mainly, the relative fold gene expression in swollen and unswollen tubers effectively revealed that PaSWEETs (7, 9, and 12) were highly expressed (300-, 120-, and 100-fold) in swollen tubers. To further elucidate the function of PaSWEETs (7, 9, and 12), their subcellular location was confirmed by inserting them into tobacco leaves, and it was noted that these genes were present on the cell membrane. On the basis of the overall results, it is suggested that PaSWEETs (7, 9, and 12) are the candidate genes involved in swollen tuber formation in P. anserina. In crux, we speculated that our study provides a valuable theoretical base for further in-depth function analysis of the PaSWEET gene family and their role in tuber development and further enhancing the molecular breeding of Potentilla anserina.
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Fragrance is an important feature of ornamental lilies. Components of volatile substances and important genes for monoterpene synthesis in the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway were examined in this study. Twenty volatile compounds (2 in the budding stage, 3 in the initial flowering stage, 7 in the semi-flowering stage, 17 in the full-flowering stage, and 5 in withering stage) were detected in the Oriental lily 'Sorbonne' using gas chromatography-mass spectrometry. The semi- and full-flowering stages were key periods for volatile substance production and enzyme function. Sequence assembly from samples collected during all flowering stages resulted in the detection of 274,849 genes and 129,017 transcripts. RNA sequencing and heatmapping led to the detection of genes in the MEP monoterpene metabolism pathway. Through gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis, we extracted key genes (LiDXS2, LiLIS, and LiMYS) and transcription factors (in the bHLH, MYB, HD-ZIP, and NAC families) associated with the MEP pathway. Tissue localization revealed that LiDXS2, LiLIS, and LiMYS were expressed in Lilium 'Sorbonne' petals in the full-flowering stage. Genes regulating the 1-deoxy-D-X-lignone-5-phosphate synthase family of rate-limiting enzymes, involved in the first step of monoterpene synthesis, showed high expression in the semi- and full-flowering stages. LiDXS2 was cloned and localized in chloroplast subcells. The relative expression of terpene-related genes in the MEP and mevalonic acid pathways of wild-type and LiLIS/LiMYS transgenic Arabidopsis thaliana, and changes in chemical composition, confirmed that LiLIS/LiMYS regulates the monoterpene synthesis pathway. The results of this study provide a theoretical basis for the synthesis of lily aromatic substances and the cultivation of new garden flower varieties.
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BACKGROUND: Laparoscopic surgery is controversial for patients with clinical T4b colorectal cancer (CRC) who require multivisceral resection (MVR). This study aims to explore and compare the safety and long-term oncological outcomes of laparoscopic surgery and open surgery for patients with clinical T4b CRC. MATERIALS AND METHODS: This study was a retrospective cohort study based on a multicentre database. According to the operation method, the patients were divided into a laparoscopic MVR group and an open MVR group. The short-term and long-term outcomes were compared. RESULTS: From January 2010 to December 2021, a total of 289 patients in the laparoscopic MVR group and 349 patients in the open MVR group were included. After propensity score matching, patients were stratified into a laparoscopic MVR group (n = 163) and an open MVR group (n = 163). Compared with the open MVR group, the laparoscopic MVR group had less blood loss (100 vs. 200, p < 0.001), a shorter time to first flatus (3 vs. 4, P < 0.001), a shorter postoperative hospital stay (10 vs. 12, P < 0.001), and a lower incidence of surgical site infection (2.5 % vs. 8.0 %, P = 0.043). The Kaplan-Meier curves showed that the two groups had similar overall survival (P = 0.283) and disease-free survival (P = 0.152). CONCLUSION: Compared with open MVR, laparoscopic MVR had less blood loss, fewer surgical site infection complications, faster recovery and a shorter hospital stay. The long-term survival outcome of laparoscopic MVR was not inferior to that of open MVR.
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Neoplasias Colorretais , Laparoscopia , Humanos , Resultado do Tratamento , Infecção da Ferida Cirúrgica/etiologia , Estudos Retrospectivos , Laparoscopia/métodos , Neoplasias Colorretais/cirurgiaRESUMO
2-C-methyl-D-erythritol-phosphate cytidylyltransferase (MCT) is a key enzyme in the MEP pathway of monoterpene synthesis, catalyzing the generation of 4- (5'-pyrophosphate cytidine)-2-C-methyl-D-erythritol from 2-C-methyl-D-erythritol-4-phosphate. We used homologous cloning strategy to clone gene, LiMCT, in the MEP pathway that may be involved in the regulation of floral fragrance synthesis in the Lilium oriental hybrid 'Sorbonne.' The full-length ORF sequence was 837 bp, encoding 278 amino acids. Bioinformatics analysis showed that the relative molecular weight of LiMCT protein is 68.56 kD and the isoelectric point (pI) is 5.12. The expression pattern of LiMCT gene was found to be consistent with the accumulation sites and emission patterns of floral fragrance monoterpenes in transcriptome data (unpublished). Subcellular localization indicated that the LiMCT protein is located in chloroplasts, which is consistent with the location of MEP pathway genes functioning in plastids to produce isoprene precursors. Overexpression of LiMCT in Arabidopsis thaliana affected the expression levels of MEP and MVA pathway genes, suggesting that overexpression of the LiMCT in A. thaliana affected the metabolic flow of C5 precursors of two different terpene synthesis pathways. The expression of the monoterpene synthase AtTPS14 was elevated nearly fourfold in transgenic A. thaliana compared with the control, and the levels of carotenoids and chlorophylls, the end products of the MEP pathway, were significantly increased in the leaves at full bloom, indicating that LiMCT plays an important role in regulating monoterpene synthesis and in the synthesis of other isoprene-like precursors in transgenic A. thaliana flowers. However, the specific mechanism of LiMCT in promoting the accumulation of isoprene products of the MEP pathway and the biosynthesis of floral monoterpene volatile components needs further investigation.
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Arabidopsis , Butadienos , Hemiterpenos , Lilium , Fosfatos Açúcares , Lilium/genética , Lilium/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Monoterpenos/metabolismo , Eritritol/metabolismo , Clonagem Molecular , Regulação da Expressão Gênica de PlantasRESUMO
Brackish water stands as a promising alternative to mitigate freshwater scarcity in arid regions. However, its application poses potential threats to agricultural sustainability. There is a need to establish a clear understanding of the economic and ecological benefits. We conducted a two-year (2021-2022) field experiment to investigate the effects of four different irrigation water salinity levels on soil electrical conductivity, cotton yield, water use efficiency, CO2 emissions, and carbon sequestration. The salinity levels were designated as CK (0.85 g L-1), S1 (3 g L-1), S2 (5 g L-1), and S3 (8 g L-1). Results indicated that using irrigation water with high salinity (≥5 g L-1) led to the accumulation of salt in the soil, and a decrease in plant biomass and seed cotton yield. Compared to CK, the S3 treatment decreased by 18.72 % and 20.10 % in the respective two years. Interestingly, using brackish water (3 L-1 and 5 g L-1) decreased the rate and cumulative CO2 emissions, and increased the carbon emission efficiency and carbon sequestration by 0.098-0.094 kg kg-1 and 871-1859 kg ha-1 in 2021, 0.098-0.094 kg kg-1 and 617-1995 kg ha-1 in 2022, respectively. To comprehensively evaluate the tradeoff between economic and ecological benefits, we employed the TOPSIS method, and S1 was identified as the optimal irrigation salinity. Through fitting analysis, the most suitable irrigation salinity levels for 2021 and 2022 were determined as 3.52 g L-1 and 3.31 g L-1, respectively. From the perspective of water conservation, salinity management, yield improvement, and reduction of CO2 emissions, it is feasible to utilize brackish water for irrigation purposes, as long as the salinity does not exceed 3.52 g L-1 (first year) and 3.31 g L-1 (second year).
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BACKGROUND: It remains unclear whether laparoscopic multisegmental resection and anastomosis (LMRA) is safe and advantageous over traditional open multisegmental resection and anastomosis (OMRA) for treating synchronous colorectal cancer (SCRC) located in separate segments. AIM: To compare the short-term efficacy and long-term prognosis of OMRA as well as LMRA for SCRC located in separate segments. METHODS: Patients with SCRC who underwent surgery between January 2010 and December 2021 at the Cancer Hospital, Chinese Academy of Medical Sciences and the Peking University First Hospital were retrospectively recruited. In accordance with the inclusion and exclusion criteria, 109 patients who received right hemicolectomy together with anterior resection of the rectum or right hemicolectomy and sigmoid colectomy were finally included in the study. Patients were divided into the LMRA and OMRA groups (n = 68 and 41, respectively) according to the surgical method used. The groups were compared regarding the surgical procedure's short-term efficacy and its effect on long-term patient survival. RESULTS: LMRA patients showed markedly less intraoperative blood loss than OMRA patients (100 vs 200 mL, P = 0.006). Compared to OMRA patients, LMRA patients exhibited markedly shorter postoperative first exhaust time (2 vs 3 d, P = 0.001), postoperative first fluid intake time (3 vs 4 d, P = 0.012), and postoperative hospital stay (9 vs 12 d, P = 0.002). The incidence of total postoperative complications (Clavien-Dindo grade: ≥ II) was 2.9% and 17.1% (P = 0.025) in the LMRA and OMRA groups, respectively, while the incidence of anastomotic leakage was 2.9% and 7.3% (P = 0.558) in the LMRA and OMRA groups, respectively. Furthermore, the LMRA group had a higher mean number of lymph nodes dissected than the OMRA group (45.2 vs 37.3, P = 0.020). The 5-year overall survival (OS) and disease-free survival (DFS) rates in OMRA patients were 82.9% and 78.3%, respectively, while these rates in LMRA patients were 78.2% and 72.8%, respectively. Multivariate prognostic analysis revealed that N stage [OS: HR hazard ratio (HR) = 10.161, P = 0.026; DFS: HR = 13.017, P = 0.013], but not the surgical method (LMRA/OMRA) (OS: HR = 0.834, P = 0.749; DFS: HR = 0.812, P = 0.712), was the independent influencing factor in the OS and DFS of patients with SCRC. CONCLUSION: LMRA is safe and feasible for patients with SCRC located in separate segments. Compared to OMRA, the LMRA approach has more advantages related to short-term efficacy.
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This study reports the synthesis of CdS/WS2 composites via a green and ultra-low-cost hydrothermal method. By controlling the relative mass ratio between WS2 and CdS, an n-n type CdS/WS2 heterostructure, with excellent NH3 gas-sensitive properties, was developed and investigated at room temperature. Compared with pristine WS2 and CdS, the CdS/WS2-40%wt composite exhibited excellent selectivity of more than 4 orders of magnitude for sensing NH3, a very short recovery time of 3 s, and ultrahigh selectivity at room temperature. The large specific surface area of the CdS/WS2 composite increased the active sites for the gas-sensitive reaction. Additionally, the 2D morphology of CdS/WS2 and the heterojunction formed between WS2 and CdS contributed to the improved performance. Anti-humidity interference tests showed that the CdS/WS2 sample remained stable under real-time monitoring of NH3 at different ambient humidity values. This study paves the way for designing high-performance gas sensors operating at room temperature.
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Elastic strain sensor nanocomposites are emerging materials of high scientific and commercial interest. This study analyzes the major factors influencing the electrical behavior of elastic strain sensor nanocomposites. The sensor mechanisms were described for nanocomposites with conductive nanofillers, either dispersed inside the polymer matrix or coated onto the polymer surface. The purely geometrical contributions to the change in resistance were also assessed. The theoretical predictions indicated that maximum Gauge values are achieved for mixture composites with filler fractions slightly above the electrical percolation threshold, especially for nanocomposites with a very rapid conductivity increase around the threshold. PDMS/CB and PDMS/CNT mixture nanocomposites with 0-5.5 vol.% fillers were therefore manufactured and analyzed with resistivity measurements. In agreement with the predictions, the PDMS/CB with 2.0 vol.% CB gave very high Gauge values of around 20,000. The findings in this study will thus facilitate the development of highly optimized conductive polymer composites for strain sensor applications.
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In this paper, the heterostructure of MoS2/WS2 was prepared by a hydrothermal method; the n-n heterostructure was demonstrated using TEM combined with Mott-Schottky analysis. The valence and conduction band positions were further identified by the XPS valence band spectra. The NH3-sensing properties were assessed at room temperature by changing the mass ratio of the MoS2 and WS2 components. The 50 wt%-MoS2/WS2 sample exhibited the best performance, with a peak response of 23643% to NH3 at a concentration of 500 ppm, a minimum detection limit of 20 ppm, and a fast recovery time of 2.6 s. Furthermore, the composites-based sensors demonstrated an excellent humidity immune property with less than one order of magnitude in the humidity range of 11-95% RH, revealing the practical application value of these sensors. These results suggest that the MoS2/WS2 heterojunction is an intriguing candidate for fabricating NH3 sensors.
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Beta vulgaris var. cicla is an edible, ornamental and horticultural plant. However, the difference of components and contents of betalain in beets with different leaf color are not well understood. Here, the stress resistance and metabolites of two B. vulgaris var. cicla cultivars were determined. The differences in stress resistance between red leaf-colored chard (RC) and yellow leaf-colored chard (YC) were positively related to betacyanins (BC) and betaxathins (BX) content in the leaves. Furthermore, a total of 3615 distinct metabolites were identified by UPLC-QTOF-MS in two cultivars, including 70 alkaloids and their derivatives, 249 flavonoids, and 264 terpenoids. There were 17 metabolites attributed to betalain biosynthesis pathway, seven of nine BC were up-regulated, and eight BX showed no significant difference in RC compared with YC. The contents of celosianin II and betanin were the highest BC in RC, at approximately 84.38 and 19.97 times that of YC, respectively. The content of portulacaxanthin II was the highest BX in two beets. Additionally, the BvCYP450 genes were identified based on genome, and the members that might be involved in betalain biosynthesis were screened. BvCYP76AD27, a member of the BvCYP76AD subfamily, had a higher expression level in RC than YC under freezing, drought and shading stress. In yeast Saccharomyces cerevisiae, BvCYP76AD5 and BvCYP76AD27 only hydroxylated tyrosine to L-DOPA, which was transformed into portulacaxanthin II by 4,5-DOPA extradiol dioxygenase. The results contribute to illustrating the molecular mechanism of betalain biosynthesis and provide useful information for further investigation of beet chemistry and sufficient utilization of this species.
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Beta vulgaris , Betalaínas , Betalaínas/química , Betalaínas/metabolismo , Beta vulgaris/genética , Tirosina/metabolismo , Levodopa/análise , Levodopa/metabolismo , Folhas de Planta/metabolismo , Saccharomyces cerevisiae/metabolismoRESUMO
Trehalose, trehalose-6-phosphate synthase (TPS),and trehalose-6-phosphatase (TPP) have been reported to play important roles in plant abiotic stress and growth development. However, their functions in the flowering process of Rosa hybrida have not been characterized. In this study we found that, under a short photoperiod or weak light intensity, the content of trehalose in the shoot apical meristem of Rosa hybrida cv 'Carola' significantly decreased, leading to delayed flowering time. A total of nine RhTPSs and seven RhTPPs genes were identified in the genome. Cis-element analysis suggested that RhTPS and RhTPP genes were involved in plant hormones and environmental stress responses. Transcriptome data analysis reveals significant differences in the expression levels of RhTPSs and RhTPPs family genes in different tissues and indicates that RhTPPF and RhTPPJ are potential key genes involved in rose flower bud development under different light environments. The results of quantitative real-time reverse transcription (qRT-PCR) further indicate that under short photoperiod and weak light intensity all RhTPP members were significantly down-regulated. Additionally, RhTPS1a, RhTPS10, and RhTPS11 were up-regulated under a short photoperiod and showed a negative correlation with flowering time and trehalose content decrease. Under weak light intensity, RhTPS11 was up-regulated and negatively regulated flowering, while RhTPS5, RhTPS6, RhTPS7b, RhTPS9, and RhTPS10 were down-regulated and positively regulated flowering. This work lays the foundation for revealing the functions of RhTPS and RhTPP gene families in the regulation of rose trehalose.
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BACKGROUND: Delayed gastric emptying (DGE) is one of the most common complications after pancreaticoduodenectomy (PD). There is currently no widely accepted procedure for PD to reduce the incidence of DGE. Our institution attempts to perform subtotal gastrectomy in patients undergoing PD to reduce DGE. Here we aimed to evaluate the effectiveness and safety of PD with subtotal gastric resection. METHODS: Patients who underwent PD between January 2014 and December 2021 were reviewed. They were stratified by extent of gastrectomy into a conventional PD group (PD that resected approximately 1/3 of the distal stomach) and a subtotal gastrectomy PD group (PD that resected approximately 3/4 of the distal stomach), which were compared in terms of intraoperative and postoperative parameters. RESULT: From January 2014 to December 2021, a total of 512 patients underwent PD in the Department of Hepatobiliary Surgery, Peking University People's Hospital. Nineteen patients were excluded from this study due to benign disease. A total of 493 patients were included, with 378 in the conventional PD group and 115 in the subtotal gastrectomy PD group. Compared with the conventional PD group, the subtotal gastrectomy PD group had a lower incidence of DGE (8.7% vs. 17.7%, p = 0.019), and a shorter hospital stay. Multivariate analysis showed that conventional PD and higher body mass index were independent risk factors for grade B/C DGE. CONCLUSION: This study showed that, compared with conventional PD, subtotal gastrectomy PD can reduce the incidence of DGE and shorten the length of hospital stay. At the same time, subtotal gastrectomy PD is comparable to conventional PD in terms of surgical safety. Furthermore, high BMI is an independent risk factor for postoperative DGE.
Assuntos
Gastroparesia , Pancreaticoduodenectomia , Humanos , Pancreaticoduodenectomia/efeitos adversos , Pancreaticoduodenectomia/métodos , Gastroparesia/epidemiologia , Gastroparesia/etiologia , Gastroparesia/prevenção & controle , Incidência , Estudos Retrospectivos , Resultado do Tratamento , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Gastrectomia/métodos , Fatores de Risco , Esvaziamento GástricoRESUMO
The tribological characteristics of ultra-high molecular weight polyethylene (UHMWPE) under unsaturated lubrication of water and brine were studied. The friction coefficients and wear rates of UHMWPE at different applied loads and sliding speeds were recorded by field tests, and the effects of load and speed on the friction properties of UHMWPE were analyzed. The results showed that under certain liquid drop (about 150-170 mL/h) lubrication, the tribological behaviors of UHMWPE were better than those of dry sliding, and the friction coefficient and wear rate of UHMWPE were reduced by more than 39% and 10% respectively. The lubrication form of UHMWPE gradually transited from saturated lubrication to unsaturated lubrication with the increase in applied load or sliding speed. The evaporation of water caused by frictional heat affected the water content between the surface of UHMWPE and the counterface, which was the main reason for the change in the lubrication form. In the current work, the critical values for the change of lubrication mode were 70 N and 700 r/min for load and speed, respectively, beyond which UHMWPE was in unsaturated lubrication. Under brine-unsaturated lubrication, the anti-friction property of UHMWPE was better than that in water-unsaturated lubrication at high speed because the precipitated salt granules played a ball effect, which was opposite to that under saturated lubrication. The study of the wear resistance with surface profiler showed that the wear rate of UHMWPE under water-unsaturated lubrication was 9% lower than that under brine-unsaturated lubrication at 110 N load. While the wear resistance of UHMWPE under brine-unsaturated lubrication was better than that in water-unsaturated lubrication at high speed, the wear rate of UHMWPE under brine-unsaturated lubrication was 10% lower than that under water-unsaturated lubrication at 1100 r/min speed.
RESUMO
BACKGROUND: The prognosis of cerebrovascular diseases treated with mechanical ventilation during perioperative has not been clearly reported. AIM: To analyze mortality and functional disability and to determine predictors of unfavorable outcome in the patients with cerebrovascular diseases treated with mechanical ventilation. METHODS: A retrospective follow-up study of 111 cerebrovascular disease patients who underwent mechanical ventilation during the perioperative period in the First Hospital of Jilin University from June 2016 to June 2019 was performed. Main measurements were mortality and functional outcome in-hospital and after 3-month follow-up. According to the modified rankin scale (mRS), the functional outcome was divided into three groups: Good recovery (mRS ≤ 3), severe disability (mRS = 4 or 5) and death (mRS = 6). Univariate analysis was used to compare the differences between three functional outcomes. Multivariate logistic regression analysis was used to for risk factors of mortality and severe disability. RESULTS: The average age of 111 patients was 56.46 ± 12.53 years, 59 (53.15%) were males. The mortality of in-hospital and 3-month follow-up were 36.9% and 45.0%, respectively. Of 71 discharged patients, 46.47% were seriously disabled and 12.67% died after three months follow-up. Univariate analysis showed that preoperative glasgow coma scale, operation start time and ventilation reasons had statistically significant differences in different functional outcomes. Multiple logistic regression analysis showed that the cause of ventilation was related to the death and poor prognosis of patients with cerebrovascular diseases. Compared with brainstem compression, the risk of death or severe disability of pulmonary disease, status epilepticus, impaired respiratory center function, and shock were 0.096 (95%CI: 0.028-0.328), 0.026 (95%CI: 0.004-0.163), 0.095 (95%CI: 0.013-0.709), 0.095 (95%CI: 0.020-0.444), respectively. CONCLUSION: The survival rate and prognostic outcomes of patients with cerebrovascular diseases treated with mechanical ventilation during the perioperative period were poor. The reason for mechanical ventilation was a statistically significant predictor for mortality and severe disability.