Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 831
Filtrar
1.
Surg Endosc ; 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32444970

RESUMO

BACKGROUND: Laparoscopic cholecystectomy (LC) is the standard treatment for acute cholecystitis (AC), and it should be performed within 72 h of symptoms onset if possible. In many undesired situations, LC was performed beyond the golden 72 h. However, the safety and feasibility of prolonged LC (i.e., performed more than 72 h after symptoms onset) are largely unknown, and therefore were investigated in this study. METHODS: We retrospectively enrolled the adult patients who were diagnosed as AC and were treated with LC at the same admission between January 2015 and October 2018 in an emergency department of a tertiary academic medical center in China. The primary outcome was the rate and severity of adverse events, while the secondary outcomes were length of hospital stay and costs. RESULTS: Among the 104 qualified patients, 70 (67.3%) underwent prolonged LC and 34 (32.7%) underwent early LC (< 72 h of symptom onset). There were no differences between the two groups in mortality rate (none for both), conversion rates (prolonged LC 5.4%, and early LC 8.8%, P = 0.68), intraoperative and postoperative complications (prolonged LC 5.7% and early LC 2.9%, P ≥ 0.99), operation time (prolonged LC 193.5 min and early LC 198.0 min, P = 0.81), and operation costs (prolonged LC 8,700 Yuan, and early LC 8,500 Yuan, P = 0.86). However, the prolonged LC was associated with longer postoperative hospitalization (7.0 days versus 6.0 days, P = 0.03), longer total hospital stay (11.0 days versus 8.0 days, P < 0.01), and subsequently higher total costs (40,400 Yuan versus 31,100 Yuan, P < 0.01). CONCLUSIONS: Prolonged LC is safe and feasible for patients with AC for having similar rates and severity of adverse events as early LC, but it is also associated with longer hospital stay and subsequently higher total cost.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32444999

RESUMO

This study reports the effects of early-life lactoferrin (LF) intervention on the colonic microbiota, intestinal function and mucosal immunity in suckling piglets. A total of 60 Duroc × Landrace × Yorkshire suckling piglets from six sows were assigned to the control (CON) and LF groups in litters. The LF group piglets were fed 0.5 g/kg body weight of LF solution per day, and the CON group piglets were fed the same dose of physiological saline for a week. Six piglets from the two groups were randomly chosen and euthanised on days 8 and 21. The LF group piglets had higher ACE and Chao1 indices of colonic microbiota than the CON group piglets (P < 0.05). In addition, the LF group piglets had a higher abundance of Roseburia (P < 0.05) and a lower abundance of Escherichia-Shigella (P < 0.05) in the colonic digesta. The LF group piglets also had a higher concentration of butyrate (P < 0.05) in the colonic digesta. Moreover, the LF group piglets had a higher gene expression of occludin (P < 0.05) in the colonic mucosa. In addition, the gene expression of MUC4 was upregulated in the LF group piglets compared with that in the CON group on day 21 (P < 0.05), and the lower gene expression of TLR-4 was found in the LF group compared with the CON group on day 8 (P < 0.05). Furthermore, the concentration of IL-10 was increased in the LF group on day 8 (P < 0.05), while the LF group piglets had a higher concentration of sIgA and lower concentrations of IL-1α and IL-1ß (P < 0.05) in the colonic mucosa. These results suggest that early-life LF intervention can modulate the composition of colonic microbiota and improve the intestinal function in suckling piglets.Key Points• Early-life LF intervention significantly modulated colon microbiota.• Early-life LF intervention can improve the colon health.• The colon microbiota plays an important role in host health.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32459953

RESUMO

Solar-blind photodetectors have widespread applications due to the unique merit of "black background" on the earth. However, most solar-blind photodetectors reported previously underwent quite low rejection ratio (R200 nm/R280 nm < 103), and were interfered by the light longer than 280 nm. Herein, by an ambient pressure chemical vapor deposition (CVD) method, large-area, clean and uniform two-dimensional (2D) multilayer h-BN films with different thickness have been successfully synthesized on Au foils. The synthesized multilayer h-BN film is transparent to spectra longer than 280 nm, showing excellent optical and optoelectronic properties to weak solar-blind light (µW/cm2). This sensitive solar-blind h-BN photodetector exhibits ultrahigh rejection ratio (R220 nm/R280 nm >103 and R220 nm/R290 nm>104), low dark current (102 fA), large detectivity (3.9 × 1010 Jones). It is noteworthy that the rejection ratio (R220 nm/R290 nm) here is superior to most previous ones based on traditional semiconductors. This large-scale, clean and uniform multilayer h-BN film will contribute to the progress of next generation optoelectronic devices.

4.
DNA Cell Biol ; 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32460527

RESUMO

Prostate cancer is the second most common cancer and the fifth cause of cancer death in males. Currently, there are no effective therapies for prostate cancer yet, and the status of treatment remains severe. In this study, we analyzed the composition of tumor-infiltrating immune cells (TIICs) in prostate cancer and paracancerous samples based on the gene expression profiles using CIBERSORT. Calculation of the TIIC subset proportions in 52 paired prostate cancer and paracancerous samples showed that their proportions were similar in intergroup and varied in intragroup. Compared with the paracancerous samples, the proportion of M0 macrophages was significantly increased in prostate cancer samples. Cox regression analysis using the TIIC subpopulations as continuous variables revealed that high plasma cell proportion was associated with poor 3-year Disease-Free Survival (DFS) in prostate cancer (hazard ratios = 1.8e-76, p = 0.001). Moreover, three immune clusters, which presented distinct prognosis, were identified using hierarchical clustering analysis based on the proportions of TIIC subpopulations. Among them, cluster 1 had superior 3-year DFS, while cluster 3 showed inferior 3-year DFS (p = 0.025). In summary, our research provided a comprehensive analysis on the TIIC composition in prostate cancer and suggested that both plasma cells and different cluster patterns were associated with the prostate cancer prognosis, which should be helpful for the clinical surveillance and treatment of prostate cancer.

5.
Cell Death Dis ; 11(5): 357, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32393776

RESUMO

In recent years, micropeptides have been increasingly identified as important regulators in various biological processes. However, whether micropeptides are functionally conserved remains largely unknown. Here, we uncovered a micropeptide with evolutionarily conserved roles in myogenesis. RNA-seq data analysis of proliferating mouse satellite cells (SCs) and differentiated myotubes identified a previously annotated lncRNA, MyolncR4 (1500011K16RIK), which is upregulated during muscle differentiation. Significantly, MyolncR4 is highly conserved across vertebrate species. Multiple lines of evidence demonstrate that MyolncR4 encodes a 56-aa micropeptide, which was named as LEMP (lncRNA encoded micropeptide). LEMP promotes muscle formation and regeneration in mouse. In zebrafish, MyolncR4 is enriched in developing somites and elimination of LEMP results in impaired muscle development, which could be efficiently rescued by expression of the mouse LEMP. Interestingly, LEMP is localized at both the plasma membrane and mitochondria, and associated with multiple mitochondrial proteins, suggestive of its involvement in mitochondrial functions. Together, our work uncovers a micropeptide that plays an evolutionarily conserved role in skeletal muscle differentiation, pinpointing the functional importance of this growing family of small peptides.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32378872

RESUMO

Multilayer InSe is a promising material for high-performance optoelectronic applications because of its small direct band gap and good light absorption. However, as a photoconductive photodetector, multilayer InSe photodetectors endure large dark current and high driving power. In this work, we study the electrical properties of InGaSe alloys and demonstrate the high-performance devices based on multilayer InSe-In0.24Ga0.76Se van der Waals heterojunctions (vdWHs). The electrical properties of InGaSe alloy samples strongly depend on the ratio of In to Ga, and the In0.24Ga0.76Se alloy shows a p-type transport behavior. More importantly, a multilayer InSe-In0.24Ga0.76Se vdWH device is demonstrated as a high-performance forward diode, photodiode, and self-powered photodetector (SPPD). The multilayer InSe-In0.24Ga0.76Se diode shows a high forward rectification ratio of over 103 without gate modulation at room temperature, which is superior to most of the multilayer vdWH devices. Moreover, the vdWH photodiode has a broadband photoresponse spectrum (400-1000 nm) and a high-performance photoresponse. The light switching ratio, detectivity (D*), and responsivity (R) are 103, 1012 Jones, and 49 A W-1 for 400 nm illumination, respectively. Furthermore, the vdWH SPPD also shows a sensitive photoresponse to a broadband spectrum of 400-1000 nm. Our work offers an opportunity for multilayer vdWH device applications in high-performance electronic and optoelectronic devices.

7.
Small ; : e1907233, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32406198

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignant tumors with extremely poor prognosis due to the later stage diagnosis when surgical resection is no longer applicable. Alternatively, the traditional gene therapy which drives pancreatic cancer cells into an inactive state and inhibiting the proliferation and metastasis, presents potentials to safely inhibit pancreatic cancer progression, but unfortunately has received limited success to date. Here, an efficient gene therapy of pancreatic cancer is shown via a peptide nucleic acid (PNA)-loaded layered double hydroxides (LDHs) nanoplatform. Compared with the traditional DNA- or RNA-based gene therapies, the gene therapy using PNA features great advantages in recognizing and hybridizing with the target mutant sequences to form PNA-DNA hybrids with significantly enhanced stability due to the absence of electrostatic repulsion, and the constrained flexibility of the polyamide backbone. Moreover, ultrasmall LDHs are engineered to load PNA and the obtained PNA-loaded LDH platform (LDHs/PNA) is capable of efficiently and selectively targeting the intranuclear mutant sequences thanks to the proton sponge effect. Treatments with LDHs/PNA demonstrate markedly inhibited growth of pancreatic cancer xenografts via a cancer cell proliferation suppression mechanism. The results demonstrate the great potentials of LDHs/PNA as a highly promising gene therapy agent for PDAC.

8.
Cell Rep ; 31(5): 107596, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32375046

RESUMO

Hypotonic stress causes the activation of swelling-activated nonselective cation channels (NSCCs), which leads to Ca2+-dependent regulatory volume decrease (RVD) and adaptive maintenance of the cell volume; however, the molecular identities of the osmosensitive NSCCs remain unclear. Here, we identified TMEM63B as an osmosensitive NSCC activated by hypotonic stress. TMEM63B is enriched in the inner ear sensory hair cells. Genetic deletion of TMEM63B results in necroptosis of outer hair cells (OHCs) and progressive hearing loss. Mechanistically, the TMEM63B channel mediates hypo-osmolarity-induced Ca2+ influx, which activates Ca2+-dependent K+ channels required for the maintenance of OHC morphology. These findings demonstrate that TMEM63B is an osmosensor of the mammalian inner ear and the long-sought cation channel mediating Ca2+-dependent RVD.

9.
Nanotechnology ; 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32365337

RESUMO

Conventional solitons (CSs) as well as bound-state solitons in a passively mode-locked erbium-doped fiber (EDF) laser based on 1T-phase titanium diselenide (1T-TiSe2) saturable absorber (SA) have been systematically demonstrated for the first time. The mode locker is assembled by sandwiching the 1T-TiSe2 film between two fiber ferrules to improve compatibility with the all-fiber-integrated ring cavity configuration. The modulation depth, saturation intensity and nonsaturable loss of the prepared 1T-TiSe2 SA are 14.36 %, 1.33 MW/cm2 and 9.44 %, respectively. The system, by means of carefully adjusting the orientations of the polarization controller (PC), is switchable between two states: CS and bound-state CS. In the CS mode-locked regime, the oscillating wavelength is centered at 1558.294 nm with a pulse duration of 1.74 ps, a pulse repetition rate of 3.23 MHz and a maximum average output power of 2.904 mW, respectively. In the bound-state CS regime, two identical solitons form the bound-state pulses with a temporal separation of 6.1 ps, and the bound-state pulses are equally distributed at a repetition rate of 3.23 MHz, corresponding to the fundamental cavity repetition rate. The experimental results further indicate that 1T-TiSe2 SA is competitive to the existing SAs explored so far and will promote the applications of 1T-TiSe2-based SAs in the field of ultrafast lasers.

10.
Exp Cell Res ; 391(1): 111987, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32240661

RESUMO

BACKGROUND: The protein plasminogen activator inhibitor-1 (PAI-1), an inhibitor specific for urokinase plasminogen activator (uPA) and tissue plasminogen activator (tPA), has been shown to have a key role in cancer metastases. Currently, it is unknown as to whether the exocellular inhibition of PAI-1 can inhibit the migration of cancer cells. METHODS: By fusing the mutated serine protease domain (SPD) of uPA and human serum albumin (HSA), PAItrap3, a protein that traps PAI-1, was synthesized and experiments were conducted to determine if exocellular PAItrap3 attenuates PAI-1-induced cancer cell migration in vitro. RESULTS: PAItrap3 (0.8 µM) significantly inhibited the motility of MCF-7, MDA-MB-231, HeLa and 4T1 cancer cells, by 90%, 50%, 30% and 20%, respectively, without significantly altering their proliferation. The PAI-1-induced rearrangement of F-actin was significantly inhibited by PAItrap3, which produced a decrease in the number of cell protrusions by at least 20%. CONCLUSIONS: In vitro, PAItrap3 inhibited PAI-1-induced cancer cell migration, mainly through inhibiting the rearrangement of F-actin. Overall, these results, provided they can be extrapolated to humans, suggest that the PAItrap3 protein could be used as an exocellular inhibitor to attenuate cancer metastases.

11.
Chem Commun (Camb) ; 56(40): 5393-5396, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32285901

RESUMO

A cytochrome c (Cyt c)-modified glass nanopore sensing platform was constructed to sensitively detect glucose in single cells based on changes in the ionic current rectification (ICR) of the system. A difference in glucose content between single H8 and HeLa cells in their satiety or starvation states was clearly able to be detected using this method.

12.
Org Lett ; 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32233500

RESUMO

A copper-catalyzed three-component reaction of terminal alkynes, TsN3, and tertiary allylic amines is developed toward the one-pot synthesis of α-allylic amidines. The product was synthesized on gram scale under 1 mol % of catalyst loading. Transformations of products into alkenyl amine and other nitrogen-containing compounds are demonstrated without any loss of stereochemical information.

13.
Radiology ; : 201491, 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32339081

RESUMO

Background COVID-19 and pneumonia of other etiology share similar CT characteristics, contributing to the challenges in differentiating them with high accuracy. Purpose To establish and evaluate an artificial intelligence (AI) system in differentiating COVID-19 and other pneumonia on chest CT and assess radiologist performance without and with AI assistance. Methods 521 patients with positive RT-PCR for COVID-19 and abnormal chest CT findings were retrospectively identified from ten hospitals from January 2020 to April 2020. 665 patients with non-COVID-19 pneumonia and definite evidence of pneumonia on chest CT were retrospectively selected from three hospitals between 2017 and 2019. To classify COVID-19 versus other pneumonia for each patient, abnormal CT slices were input into the EfficientNet B4 deep neural network architecture after lung segmentation, followed by two-layer fully-connected neural network to pool slices together. Our final cohort of 1,186 patients (132,583 CT slices) was divided into training, validation and test sets in a 7:2:1 and equal ratio. Independent testing was performed by evaluating model performance on separate hospitals. Studies were blindly reviewed by six radiologists without and then with AI assistance. Results Our final model achieved a test accuracy of 96% (95% CI: 90-98%), sensitivity 95% (95% CI: 83-100%) and specificity of 96% (95% CI: 88-99%) with Receiver Operating Characteristic (ROC) AUC of 0.95 and Precision-Recall (PR) AUC of 0.90. On independent testing, our model achieved an accuracy of 87% (95% CI: 82-90%), sensitivity of 89% (95% CI: 81-94%) and specificity of 86% (95% CI: 80-90%) with ROC AUC of 0.90 and PR AUC of 0.87. Assisted by the models' probabilities, the radiologists achieved a higher average test accuracy (90% vs. 85%, Δ=5, p<0.001), sensitivity (88% vs. 79%, Δ=9, p<0.001) and specificity (91% vs. 88%, Δ=3, p=0.001). Conclusion AI assistance improved radiologists' performance in distinguishing COVID-19 from non-COVID-19 pneumonia on chest CT.

14.
Sheng Li Xue Bao ; 72(2): 235-242, 2020 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-32328617

RESUMO

Gliomas are malignant tumors with strong invasiveness. The current treatment strategy is surgical treatment assisted by a variety of radiotherapies, chemotherapies and immunotherapies. However, the curative efficacy is limited. Adrenergic receptor (AR) is an important stress hormone receptor, which is highly involved in the regulation of the tumorigenesis and progression of various tumors by activating different downstream signal transduction pathways. Recent studies have shown that AR is dysregulated in glioma cells and tissues, and plays an important role in a series of biological behaviors such as tumorigenesis, invasion and metastasis of glioma. This article reviews the research progress of AR in the field of glioma in recent years, which provides a theoretical basis for the prevention and treatment of glioma targeting the AR.

15.
Radiology ; : 200823, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32155105

RESUMO

Background Despite its high sensitivity in diagnosing COVID-19 in a screening population, chest CT appearances of COVID 19 pneumonia are thought to be non-specific. Purpose To assess the performance of United States (U.S.) and Chinese radiologists in differentiating COVID-19 from viral pneumonia on chest CT. Methods A total of 219 patients with both positive COVID-19 by RT-PCR and abnormal chest CT findings were retrospectively identified from 7 Chinese hospitals in Hunan Providence, China from January 6 to February 20, 2020. A total of 205 patients with positive Respiratory Pathogen Panel for viral pneumonia and CT findings consistent with or highly suspicious for pneumonia by original radiology interpretation within 7 days of each other were identified from Rhode Island Hospital in Providence, RI. Three Chinese radiologists blindly reviewed all chest CTs (n=424) to differentiate COVID-19 from viral pneumonia. A sample of 58 age-matched cases was randomly selected and evaluated by 4 U.S. radiologists in a similar fashion. Different CT features were recorded and compared between the two groups. Results For all chest CTs, three Chinese radiologists correctly differentiated COVID-19 from non-COVID-19 pneumonia 83% (350/424), 80% (338/424), and 60% (255/424) of the time, respectively. The seven radiologists had sensitivities of 80%, 67%, 97%, 93%, 83%, 73% and 70% and specificities of 100%, 93%, 7%, 100%, 93%, 93%, 100%. Compared to non-COVID-19 pneumonia, COVID-19 pneumonia was more likely to have a peripheral distribution (80% vs. 57%, p<0.001), ground-glass opacity (91% vs. 68%, p<0.001), fine reticular opacity (56% vs. 22%, p<0.001), and vascular thickening (59% vs. 22%, p<0.001), but less likely to have a central+peripheral distribution (14.% vs. 35%, p<0.001), pleural effusion (4.1 vs. 39%, p<0.001) and lymphadenopathy (2.7% vs. 10.2%, p<0.001). Conclusion Radiologists in China and the United States distinguished COVID-19 from viral pneumonia on chest CT with high specificity but moderate sensitivity. A translation of this abstract in Farsi is available in the supplement. - ترجمه چکیده این مقاله به فارسی، در ضمیمه موجود است.

16.
Int J Nurs Pract ; : e12830, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32167225

RESUMO

AIMS: To assess the effect of peer support intervention on diabetes distress in people with type 2 diabetes. BACKGROUND: Diabetes distress may be decreased by peer support intervention, but findings about the effect of peer support on diabetes distress have been mixed. DESIGN: A systematic review and meta-analysis of randomized controlled studies. DATA SOURCES: PubMed, Embase, CENTRAL, PsycINFO, Web of Science, and CINAHL databases were searched for randomized controlled trials from inception to 30 June 2018. REVIEW METHODS: Investigators assessed eligibility, extracted data, and assessed methodological quality. Standardized mean difference and 95% confidence intervals were calculated for pooled effect size. RESULTS: A total of 13 studies included in systematic review and 10 in meta-analysis. In the random-effects model, the pooled effect size showed current peer support intervention did not significantly reduce diabetes distress in type 2 diabetes population compared with usual care. CONCLUSION: High quality and well-designed studies targeting at reducing diabetes distress are needed to further test the effect of peer support intervention on diabetes distress.

17.
J Dig Dis ; 21(4): 237-245, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32166900

RESUMO

OBJECTIVE: To explore the prevalence of and risk factors for gallstone disease in Shanghai, China. METHODS: A population-based cross-sectional study was conducted in Shanghai between 2016 and 2017. Using a three-stage stratified sampling strategy, 4009 participants (1753 men and 2256 women) from 10 districts were enrolled. RESULTS: The overall prevalence of gallstones was 6.83% (6.22% for men vs 7.31% for women, P = 0.173). According to the multivariate analysis, individuals aged ≥40 years (odds ratio [OR] 3.058, 95% confidence interval [CI] 2.110-4.433, P < 0.001), hypertension (OR 1.479, 95% CI 1.076-2.034, P = 0.016), thyroid disease (OR 1.409, 95% CI 1.029-1.928, P = 0.032), a family history of gallstones (OR 2.234, 95% CI 1.362-3.662, P = 0.001) and a waist-to-height ratio ≥0.5 (OR 1.656, 95% CI 1.197-2.292, P = 0.002) had an increased risk of developing gallstones. The risk of gallstone disease was 2.232 (95% CI 1.167-4.268, P = 0.015) times higher in individuals with elevated C4 levels than in those with normal C4 levels. Diabetes (OR 4.144, 95% CI 1.171-14.671, P = 0.028) was a risk factor for the formation of gallstones with diameters ≥1 cm, and men were more susceptible to develop multiple stones (OR 2.356, 95% CI 1.321-4.200, P = 0.004). CONCLUSION: Individuals aged ≥40 years, with a history of hypertension and familial gallstones, a high waist-to-height ratio, thyroid disease and high C4 levels were related to an increased risk of gallstone disease.

18.
J Mol Diagn ; 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32205292

RESUMO

Spinal muscular atrophy (SMA) is a relatively common, life-shortening, autosomal recessive neuromuscular disease. The carrier frequency of SMA ranges from approximately 0.98% to 2.02%, depending on ethnicity. The American College of Medical Genetics has therefore recommended population screening for SMA carrier status, regardless of race or ethnicity. We performed the largest-scale carrier screening for SMA carriers in mainland China. Carrier screening was offered to 36,470 pregnant women between July 2017 and June 2019, of whom 13,069 women accepted the screening program (35.83%; 95% credibility interval (CI), 35.34%-36.33%). Copy numbers of exons 7 and 8 in the SMN1 gene were detected by real-time quantitative PCR, and the results were confirmed by multiplex ligation-dependent probe amplification. A total of 231 women were identified as carriers (1.77%; 95% CI, 1.56%-2.01%), indicating a carrier prevalence of approximately 1:56 in the population. After detailed genetic counseling, 207 paternal partners were recalled and tested. Both partners were carriers in 10 couples, of whom prenatal diagnosis was implemented in seven, and one fetus was diagnosed with SMA. Carrier screening could provide couples with informed reproductive choices. Our workflow and experience of carrier screening may facilitate the popularization of SMA carrier screening in mainland China.

19.
Chem Biodivers ; 17(4): e2000033, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32119759

RESUMO

Five traditional medicinal food from the Tibetan plateau including Nitraria tangutorum Bobrov (NT), Hippophae rhamnoides L. (HR), Lycium ruthenicum Murray (LR), Lycium barbarum L. (LB) and Rubus corchorifolius L.f. (RC) are rich in phenolic compounds. However, the detailed studies about the phenolic compounds remain scarce. Therefore, we established a rapid method for the simultaneous identification and quantification of the phenolic compounds from berries via Ultra Performance Liquid Chromatography-Quadruple-Orbitrap MS system (UPLC-Q-Orbitrap MS). This method was verified from many aspects including detection limit, quantification limit, precision, repeatability, stability, average recovery rate and recovery range, and then was used to analyze the phenolic compounds in these five species of berries. Finally, a total of 21 phenolic compounds were directly identified by comparing the retention time and exact mass, of which 14 compounds were identified by us for the first time in berries from the Tibetan plateau, including one flavonoid aglycone (myricetin), 11 phenolic acids (gallic acid, protocatechuate, chlorogenic acid, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, ferulic acid, 2-hydroxybenzeneacetic acid and ellagic acid), one flavanol (catechin) and one dihydrochalcone flavonoid (phloretin). Quantitative results showed that rutin, myricetin, quercetin and kaempferol were the main flavonoids. Moreover, a variety of phenolic acid compounds were also detected in most of the berries from the Tibetan plateau. Among these compounds, the contents of protocatechuate and chlorogenic acid were high, and high levels of catechin and phloretin were also detected in these plateau berries.

20.
Mol Plant ; 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32222483

RESUMO

Plant architecture is a complex agronomic trait and a major factor of crop yield, which is affected by several important hormones. Strigolactones (SLs) are identified as a new class hormoneinhibiting branching in many plant species and have been shown to be involved in various developmental processes. Genetical and chemical modulation of the SL pathway is recognized as a promising approach to modify plant architecture. However, whether and how the genes involved in the SL pathway could be utilized in breeding still remain elusive. Here, we demonstrate that a partial loss-of-function allele of the SL biosynthesis gene, HIGH TILLERING AND DWARF 1/DWARF17 (HTD1/D17), which encodes CAROTENOID CLEAVAGE DIOXYGENASE 7 (CCD7), increases tiller number and improves grain yield in rice. We found that the HTD1 gene had been widely utilized and co-selected with Semidwarf 1 (SD1), both contributing to the improvement of plant architecture in modern rice varieties since the Green Revolution in the 1960s. Understanding how phytohormone pathway genes regulate plant architecture and how they have been utilized and selected in breeding will lay the foundation for developing the rational approaches toward improving crop yield.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA