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1.
Food Chem ; 336: 127714, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32828014

RESUMO

Five new flavonoids (1-5), along with 25 known compounds, were isolated from the rhizomes of Potentilla anserina L. and their structures were identified using spectroscopic and chemical evidence. The extract, all fractions, and all isolated compounds were evaluated for their antioxidant, α-glucosidase, and tyrosinase inhibitory activities, and their structure-activity relationship was interpreted. The biflavanols and quercetin-3-O-α-l-rhamnopyranoside-2″-gallate (14) exhibited significant antioxidant and α-glucosidase inhibition activities. In this study, anti-tyrosinase activity and its mechanism of active compounds (potenserin C (4), potenserin D (5), and quercetin-3-O-α-l-rhamnopyranoside-2″-gallate (14)) were explored by a combination of computational simulations and kinetic studies. Kinetic studies indicated that potenserin C (4) and quercetin-3-O-α-l-rhamnopyranoside-2″-gallate (14) inhibited tyrosinase in a competitive manner, whereas potenserin D (5) acted in a reversible noncompetitive manner. The molecular docking result indicated that the substitution of the glucose moiety with galloyl and the presence of 3', 4', 5'-OH in flavonoid aglycones played a crucial role for the tyrosinase inhibiting effect. Moreover, the presence of biflavanols increased the activity against tyrosinase because of strong hydrogen binding, π-alkyl binding, and electrostatic interaction. Thus, the presented experiments developed several new lead compounds that could act as antioxidants and α-glucosidase inhibitors. Furthermore, biflavanols and quercetin-3-O-α-l-rhamnopyranoside-2″-gallate played important roles in the anti-browning activity during food processing.

2.
Org Lett ; 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33044826

RESUMO

A palladium-catalyzed cascade reaction of ß'-allenoate adducts with aryl/heteroaryl carboxamides through a vinylogous elimination/C-H functionalization/intramolecular allylation reaction sequence has been developed with high Z stereoselectivity. Various ring-fused dihydropyridinones bearing an α,ß-unsaturated ester substituent are obtained. It is the first example of application of the allenoate adducts to C-H functionalization annulations as practical precursors of hard-to-get functionalized electron-deficient 1,3-butadienes. Using air as the terminal oxidant also shows a great advantage in environmental friendliness.

3.
Artigo em Inglês | MEDLINE | ID: mdl-33044868

RESUMO

Females are protected against the development of Angiotensin II (Ang II)-induced hypertension compared with males, but the mechanisms are not completely elucidated. In the present study, we hypothesized that the effect of Ang II on macula densa nitric oxide (NO) synthase ß (NOS1ß)-mediated tubuloglomerular feedback (TGF) mechanism is different between male and female, thereby contributing to the sexual dimorphism of Ang II-induced hypertension. We used microperfusion, micropuncture, clearance of FITC-inulin, and radio telemetry to examine the sex differences in the changes of macula densa NOS1ß expression and activity, TGF response, natriuresis, and blood pressure (BP) after 2-weeks Ang II infusion in wild-type and macula densa-specific NOS1 knockout mice. In wild-type mice, Ang II induced higher expression of macula densa NOS1ß, greater NO generation by the macula densa, as well as lower TGF response in vitro and in vivo in females than in males; the increases of GFR, urine flow rate and sodium excretion in response to an acute volume expansion were significantly greater and the BP responses to Ang II were significantly less in females than in males. In contrast, these sex differences in the effects of Ang II on TGF, natriuretic response and BP were largely diminished in knockout mice. Additionally, tissue culture of human kidney biopsies (renal cortex) with Ang II resulted in a greater increase in NOS1ß expression in females than in males. In conclusion, macula densa NOS1ß-mediated TGF is a novel and important mechanism for the sex differences in Angiotensin II-Induced hypertension.

4.
Emerg Microbes Infect ; : 1-31, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33048025

RESUMO

Balamuthia mandrillaris infection is a rare and fatal disease. It has been reported globally, with most cases reported in the US. We have recorded 28 cases of Balamuthia mandrillaris infection during the past 20 years. The diagnosis was confirmed by immunohistochemical staining with polyclonal anti-Balamuthia antibody and polymerase chain reaction amplification with specific primers. Eighteen patients (64%) were male and 10 (36%) were female. Patient age ranged from 3 to 74 (mean, 27) years; 14 (50%) patients were children. Patient locations were distributed among 12 separate Provinces in China. Twenty-seven (96%) patients lived in rural areas, and 17 (61%) patients reported a history of trauma before the appearance of skin lesions. All cases presented with skin lesions as the primary symptom, and 16 (57%) cases developed encephalitis. Histopathology of skin lesions revealed granulomatous changes with histiocytes, lymphocytes, and plasma cells infiltration. Amebas were identified in all cases with immunohistochemical staining. Follow-up information was available in 27 (96%) cases. Fifteen (56%) patients died due to encephalitis and 12 (44%) were free of disease after treatment. Our results show that the clinical characteristics of Balamuthia mandrillaris infection in China are very different from those in the US. Infection of traumatized skin may play an important role in the pathogenesis of the disease in China. Encephalitis usually develops 3-4 years after skin lesions in Chinese cases. Patients with only skin lesions have a higher cure rate than patients with encephalitis.

5.
Anal Chim Acta ; 1136: 134-140, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33081937

RESUMO

In this paper, an effective and accurate ratiometric electrochemiluminescence (ECL) system based on Au-luminol and CdS quantum dots (CdS QDs) as signal probes was constructed for detecting carcinoembryonic antigen (CEA). Polyaniline (PANI) and gold nanoparticles (AuNPs) strongly enhanced the electronic transfer efficiency and the specific area of the modified sensing surface, and improved the detection sensitivity. CdS QDs functionalized DNA strands functioned as cathode ECL emitters, and the aptamer of CEA modified with Au-luminol and quencher cyanine dye (Cy5) fluorophore functioned as anode ECL emitters. After the DNA capture probe combined with CEA aptamer, the negative potential ECL response of the CdS QDs was quenched because of electrochemiluminescence resonance energy transfer (ERET) between the Cy5 fluorophore and CdS QDs. However, the positive potential ECL response of Au-luminol can still be detected. The negative potential ECL response of CdS QDs was recovered, and the positive potential ECL response of Au-luminol decreased after CEA combined with its aptamer to take Cy5 and Au-luminol off the sensing interface. Additionally, the peptide provided effective anti-fouling performance in the detection of complex samples. The ratiometric ECL sensor with anti-fouling ability can sensitively determine the concentration of CEA in human serum.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33083831

RESUMO

The central nervous system (CNS) diseases are still a major cause of morbidity and mortality throughout the world, which imposes heavy burden on the development of society. Ethionine is a non-proteinogenic amino acid having similar chemical structure and activity to that of methionine, with which it competes. Previous studies have confirmed that ethionine affects various cellular functions by inhibiting the biosynthesis of proteins, RNA, DNA, and phospholipids, or all of them. The relationship of ethionine with some CNS diseases, including neural tube defects, has been investigated recently. However, the detailed effects of ethionine on the nerve cell bioactivities and the underlying mechanisms have not been fully explored. Herein, we systematically investigated the influences of ethionine on the proliferation, differentiation, and apoptosis of neural stem cells (NSCs) and post-mitotic nerve cells. We demonstrated that ethionine inhibited cell viability by disrupting the balance between proliferation and apoptosis, prevented NSCs from differentiating into neurons and astrocytes, and blocked cell progression from G1 to S phase via reducing cyclin D1 function in nerve cells including NSCs, a mouse hippocampal neuron cell line (HT-22), and a mouse brain neuroma cell line (Neuro-2a). We speculated that the inhibitory effect of ethionine on cell viability and differentiation are associated with increased reactive oxygen species production. Our results also supported the concept that ethionine may be an underlying cause of abnormal folate metabolism-induced CNS diseases. Our findings may provide important direction for the application of abnormal folate metabolism-induced CNS diseases in future NSC-based therapies.

7.
Chem Commun (Camb) ; 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33084644

RESUMO

Exosomes have been widely considered as excellent noninvasive or minimally invasive biomarkers; however, the currently available methods for exosome detection usually need sophisticated instruments, or the sensitivity cannot be satisfactory, since the size of exosomes is very large. Nevertheless, in this work, by making use of the steric hindrance of exosomes due to their large size, we have developed a simple and sensitive method for the detection of exosomes with great potential in clinical use.

8.
Redox Biol ; 37: 101742, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33045621

RESUMO

Hyperhomocysteinemia (HHcy) is related to liver diseases, such as nonalcoholic fatty liver (NAFL). Although the precise pathogenesis of NAFL is still largely unknown, the links between organs seem to play a vital role. The current study aimed to explore the role of white adipose tissue in homocysteine (Hcy)-induced NAFL. Blood samples from nonhyperhomocysteinemia or hyperhomocysteinemia individuals were collected to assess correlation between Hcy and triglyceride (TG) or free fatty acids (FFAs) levels. C57BL/6 mice were maintained on a high-methionine diet or administered with Hcy (1.8 g/L) in the drinking water to establish an HHcy mouse model. We demonstrated that Hcy activated adipocyte lipolysis and that this change was accompanied by an increased release of FFAs and glycerol. Excessive FFAs were taken up by hepatocyte, which resulted in lipid accumulation in the liver. Treatment with acipimox (0.08 g kg -1 day -1), a potent chemical inhibitor of lipolysis, markedly decreased Hcy-induced NAFL. Mechanistically, hypoxia-inducible factor 1α (HIF1α)-endoplasmic reticulum oxidoreductin 1α (ERO1α) mediated pathway promoted H2O2 accumulation and induced endoplasmic reticulum (ER) overoxidation, ER stress and more closed ER-lipid droplet interactions, which were responsible for activating the lipolytic response. In conclusion, this study reveals that Hcy activates adipocyte lipolysis and suggests the potential utility of targeted ER redox homeostasis for treating Hcy-induced NAFL.

9.
Cell Biol Int ; 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33049093

RESUMO

Non-small-cell lung cancer (NSCLC) is one of the most common malignancies, and the occurrence of drug-resistance severely limits the efficacy of anticancer drugs in the treatment of NSCLC. Identification of new agents to reverse drug-resistance in NSCLC treatment is of great importance and urgency both clinically and scientifically. In the present study, we found that A549/Taxol cells displayed a high level of resistance to paclitaxel with the resistance index up to 231. Importantly, esomeprazole could potentiate the antiproliferative effect of paclitaxel in A549/Taxol cells, but not in A549 cells. Further exploration on the underlying mechanisms revealed that esomeprazole decreased the intracellular pH via inhibiting V-ATPase expression in A549/Taxol cells. Meanwhile, esomeprazole pretreatment significantly promoted paclitaxel-induced polymerization of tubulin and enhanced the proportion of G2/M-arrested cells in A549/Taxol cells. Unfortunately, esomeprazole could only result in a slight decrease in the expression of P-gp in A549/Taxol cells. Interestingly, esomeprazole significantly increased paclitaxel-induced apoptosis, which was impeded by the autophagy inhibitor 3-MA in A549/Taxol cells. Taken together, our data suggest that esomeprazole is a promising chemosensitizer against paclitaxel-resistant NSCLC by inducing autophagy. Our study also offers a new strategy to solve the paclitaxel-resistance problem during NSCLC treatment.

10.
Sci Rep ; 10(1): 17235, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33057239

RESUMO

Evidence on the long-term influence of climatic variables on pertussis is limited. This study aims to explore the long-term quantitative relationship between weather variability and pertussis. Data on the monthly number of pertussis cases and weather parameters in Chongqing in the period of 2004-2018 were collected. Then, we used a negative binomial multivariable regression model and cointegration testing to examine the association of variations in monthly meteorological parameters and pertussis. Descriptive statistics exhibited that the pertussis incidence rose from 0.251 per 100,000 people in 2004 to 3.661 per 100,000 persons in 2018, and pertussis was a seasonal illness, peaked in spring and summer. The results from the regression model that allowed for the long-term trends, seasonality, autoregression, and delayed effects after correcting for overdispersion showed that a 1 hPa increment in the delayed one-month air pressure contributed to a 3.559% (95% CI 0.746-6.293%) reduction in the monthly number of pertussis cases; a 10 mm increment in the monthly aggregate precipitation, a 1 °C increment in the monthly average temperature, and a 1 m/s increment in the monthly average wind velocity resulted in 3.641% (95% CI 0.960-6.330%), 19.496% (95% CI 2.368-39.490%), and 3.812 (95% CI 1.243-11.690)-fold increases in the monthly number of pertussis cases, respectively. The roles of the mentioned weather parameters in the transmission of pertussis were also evidenced by a sensitivity analysis. The cointegration testing suggested a significant value among variables. Climatic factors, particularly monthly temperature, precipitation, air pressure, and wind velocity, play a role in the transmission of pertussis. This finding will be of great help in understanding the epidemic trends of pertussis in the future, and weather variability should be taken into account in the prevention and control of pertussis.

11.
Hum Brain Mapp ; 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33058385

RESUMO

Spurred by availability of automatic segmentation software, in vivo MRI investigations of human hippocampal subfield volumes have proliferated in the recent years. However, a majority of these studies apply automatic segmentation to MRI scans with approximately 1 × 1 × 1 mm3 resolution, a resolution at which the internal structure of the hippocampus can rarely be visualized. Many of these studies have reported contradictory and often neurobiologically surprising results pertaining to the involvement of hippocampal subfields in normal brain function, aging, and disease. In this commentary, we first outline our concerns regarding the utility and validity of subfield segmentation on 1 × 1 × 1 mm3 MRI for volumetric studies, regardless of how images are segmented (i.e., manually or automatically). This image resolution is generally insufficient for visualizing the internal structure of the hippocampus, particularly the stratum radiatum lacunosum moleculare, which is crucial for valid and reliable subfield segmentation. Second, we discuss the fact that automatic methods that are employed most frequently to obtain hippocampal subfield volumes from 1 × 1 × 1 mm3 MRI have not been validated against manual segmentation on such images. For these reasons, we caution against using volumetric measurements of hippocampal subfields obtained from 1 × 1 × 1 mm3 images.

12.
J Org Chem ; 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33063514

RESUMO

A novel and efficient visible-light-induced decarboxylative cyclization/hydrogenation cascade reaction of α-oxocarboxylic acids and 2-isocyanobiaryls has been developed. Without the need of any external photosensitizer, oxidant, and reductant, this method offers a mild and green approach for the synthesis of diverse alcohols in moderate to good yields. A mechanism indicated that an electron donor-acceptor complex-driven decarboxylation, radical addition/cyclization, and in situ photochemical reduction of ketones to alcohols could be involved in the reaction.

13.
Nanoscale Horiz ; 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33063803

RESUMO

Compared with the highly active anatase TiO2, rutile TiO2 usually presents poor photocatalytic performance due to high electron-hole recombination. Herein, we propose a surface domain heterojunction (SDH) structure between adjacent micro-domains with and without chemisorbed chlorine on rutile TiO2, which utilizes the potential difference between these domains to form a built-in field that promotes charge separation. Single-crystal rutile TiO2 nanorods assembled into radial microspheres with SDHs were fabricated, and these exhibited excellent solar-driven photocatalytic hydrogen evolution, ∼8-fold higher than that of the pristine one. Experimental results and density functional theory calculations reveal that the exceptional photocatalytic performance can be attributed to the in situ formation of chemisorbed chlorine, which forms SDHs that separate electrons and holes efficiently and results in surface reconfiguration, exposing the tri-active sites, increasing the O-site active centers and enhancing the catalytic activity of the 4-coordinated (Ti4c) and 5-coordinated Ti sites (Ti5c). This SDH strategy can extend to other halogen elements and thus provides an universal approach for the rational design of high-efficiency TiO2 photocatalysts toward sustainable solar-fuel evolution.

14.
Dalton Trans ; 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33063805

RESUMO

The low surface area, poor electrical conductivity, and rapid electron-hole recombination in bulk C3N4 limit its photocatalytic activity, which makes it challenging to improve the performance of bulk C3N4. Herein, an effective strategy is proposed to fabricate Co3O4/C3N4 heterojunctions (Co3O4 nanoparticles grown on C3N4 nanosheets), where bulk C3N4 is exfoliated to thin nanosheets. The bulk C3N4 precursor was synthesized with the hydrothermal treatment of melamine solution, and Co2+ ions were then inserted into the interlayer of the precursor through a vacuum-assisted intercalation process. Subsequently, the precursor was exfoliated to C3N4 nanosheets, and 15 nm Co3O4 nanoparticles were simultaneously formed using in situ thermal polycondensation. The Brunauer-Emmett-Teller (BET) specific surface area of the prepared heterojunction was 21 times higher than that of bulk C3N4, and thus more active sites were exposed on the surface of the heterostructure. Co3O4 nanoparticles contained oxygen vacancies, and the type-II transfer mechanism between these nanoparticles and C3N4 could be used to effectively separate photogenic carriers and improve the electron mobility. As expected, the heterostructure exhibited an excellent photocatalyzed degradation rate of 99.5% for methylene blue within 30 min (10 mg catalyst, wavelength >420 nm) under visible light irradiation, which was nearly three times higher than that of bulk C3N4. Electron paramagnetic resonance (EPR) analysis indicated that ˙O2- was the main reactive oxidizing species during the degradation process.

15.
Med Phys ; 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33064863

RESUMO

PURPOSE: To investigate the effects of CT protocol and in-room x-ray technique on CyberKnife® (Accuray Inc.) tracking accuracy by evaluating end-to-end tests. METHODS: End-to-end (E2E) tests were performed for the different tracking methods (6D skull, fiducial, spine and lung) using an anthropomorphic head phantom (Accuray Inc.) and thorax phantom (CIRS Inc.). Bolus was added to the thorax phantom to simulate a large patient and to evaluate the performance of lung tracking in a more realistic condition. The phantoms were scanned with a Siemens Sensation Open 24 slice CT at low-dose (120kV, 70mAs, 1.5mm slice thickness) and high-dose (120kV, 700mAs, 1.5mm slice thickness) to generate low-dose and high-dose digitally reconstructed radiographs (DRRs). The difference in initial phantom alignment, Δ(Align), and in total targeting accuracy, E2E, were obtained for all tracking methods with low and high dose DRRs. Additionally, Δ(Align) was determined for different in-room x-ray imaging techniques (0.5 to 50mAs and 100 to 140kV) using a low-dose lung tracking plan. RESULTS: Low-dose CT scans produced images with high noise, however, for these phantoms the targets could be easily delineated on all scans. End-to-end results were less than 0.95mm for all tracking methods and all plans. The greatest difference in initial alignment Δ(Align) and E2E results between low and high dose CT protocols was 0.32mm and 0.24mm, respectively. Similar results were observed with a large thorax phantom. Tracking using di_erent in-room x-ray imaging techniques (mAs) corresponding to low exposures (resulting in high image noise) or high exposure (resulting in image saturation) had alignment accuracy Δ(Align) greater than 1mm. CONCLUSIONS: End-to-end targeting accuracy within tolerance (<0.95mm) was obtained for all tracking methods using low-dose CT protocols, suggesting that CT protocol should be set by target contouring needs. Additionally, high tracking accuracy was achieved for in in-room x-ray imaging techniques that produce high quality images.

17.
Food Chem ; 341(Pt 2): 128268, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33039742

RESUMO

To investigate the effects of exogenous melatonin (MLT) treatment on the quality of postharvest jujubes, fresh 'Lingwuchangzao', and 'Dongzao' jujubes (Zizyphus jujuba Mill) were dipped in MLT solution at the dose of 0, 50,100 and 200 µmol L-1 for 20 min. Results showed the exogenous MLT application significantly delayed the color change and firmness decline, and maintained the content of total soluble solids and titratable acidity of both jujube cultivars, (p < 0.05). It was demonstrated that the endogenous MLT content was increased by exogenous MLT treatment. Furthermore, phenolic compounds level was enhanced by MLT application, companied by the upregulated expression of main genes involved in phenolic biosynthesis, including phenylalanine ammonia-lyase, cinnamate 4-hydroxylase, chalcone synthase, flavonoid 3ß-hydroxylase, leucoanthocyanidin reductase, and anthocyanidin synthase. Given the evidence from the present study, it's proposed that the exogenous MLT approach is a promising approach for maintaining quality attributes and delaying the senescence of postharvest jujubes.

18.
Trials ; 21(1): 844, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33046128

RESUMO

BACKGROUND: Traditional Chinese medicine (TCM) has a long history of use in breast cancer, but lacking systematic evidence to support its clinical benefits. In this study, we evaluated the prophylactic and therapeutic effects of moxibustion combined with decoctions for treating chemotherapy-induced myelosuppression (CIM) in early-stage breast cancer patients. METHODS: This is a randomized controlled clinical trial single-blinded for TCM decoction but not moxibustion. Patients are equally divided into the control group without decoction and moxibustion treatment (control), the decoction+moxibustion group (MD), and the placebo+moxibustion group (MP), according to the following stratification factors: age (below 40s, 40s, 50s, and 60s or above), chemotherapy regimen (anthracyclines, taxanes, anthracyclines+taxane, and others), and chemotherapy strategy (adjuvant and neoadjuvant). The TCM decoction is Wenshen Shengbai Decoction. The anticipated sample size is 462 cases (154 cases in each group). All participants are expected to treat with chemotherapy and recombinant human granulocyte colony-stimulating factor (rhG-CSF). The primary outcomes include the proportion of patients with relief of leukopenia and/or neutropenia, the myelosuppression-associated serious adverse event including grade 3-4 leukopenia and/or neutropenia, and febrile neutropenia, and the dose of rhG-CSF. The secondary outcomes include chemotherapy adherence, stratified analysis, adverse reactions, quality of life by EORTC Breast-Cancer-Specific Quality of Life Questionnaire including EORTC QLQ-C30 (V3.0) and QLQ-BR23, TCM Constitution, and 3-year disease-free survival and overall survival. Baseline information including age, surgical approach, chemotherapy regimen and strategy, pathological stage, and molecular subtype will be recorded. DISCUSSION: This will be the first randomized controlled trial to evaluate the efficacy of moxibustion combined with TCM decoction in treating CIM in early-stage breast cancer patients, aiming to standardize the TCM decoction and moxibustion method, thus providing evidence for its clinical benefit. TRIAL REGISTRATION: chictr.org.cn ChiCTR-INR-16009557 . Registered on 23 October 2016.

19.
Zootaxa ; 4821(3): zootaxa.4821.3.6, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-33056314

RESUMO

In the present study, the complete mitochondrial genome of Smerinthus planus Walker (Lepidoptera: Sphingidae) was sequenced and analyzed to add additional traits for expanding our knowledge on systematics and phylogenetics of world-wide studied Sphingidae moths. The mitochondrial genome is a circular double-stranded DNA molecule, 15368 bp in size. It includes 13 protein-coding genes (PCGs), two ribosomal RNA (rRNA) genes, twenty-two transfer RNA (tRNA) genes, and an adenine (A) + thymine (T) rich region. All the PCGs start with the typical ATN start codons, except for the nad5 gene, which initiates with TTA. The codon usage analysis revealed that Phe, Ile, Lys, Leu, Asn, and Tys were the most common amino acids, while Cys and Trp were least common. Among the 13 PCGs, nine genes harbor the complete termination codon TAA, whereas the remaining four genes (nad1, cob, nad4, and nad3) terminate with TAG. The A+T rich region of S. planus is 318 bp. This region displays the highest A+T rich content, accounting for 91.50%, with both AT skew (-0.09) and GC skew (-0.26) are negative. Like other Lepidopterans, the A+T-rich region of the S. planus also contains some conserved regions, including the motif 'ATAGA' followed by an 18 bp poly-T stretch, a microsatellite-like (AT)8 and a poly-A element. Phylogenetic relationships, based on nucleotide sequences from the genomes of 31 species, confirmed that S. planus belong to the Sphingidae family. This study is aimed to improve the mitochondrial genome database of moths and provide valuable information for studying the genetic evolution and phylogeny of Lepidopteran species.


Assuntos
Genoma Mitocondrial , Mariposas , Animais , Evolução Molecular , Filogenia , RNA de Transferência
20.
Artigo em Inglês | MEDLINE | ID: mdl-33079493

RESUMO

BACKGROUND: To evaluate the failure patterns and prognostic factors in patients with cervical node-negative nasopharyngeal carcinoma (NPC) in the intensity-modulated radiotherapy (IMRT) era. METHODS: Patients with cervical node-negative NPC treated with IMRT at the Sun Yat-sen University Cancer Center between February 2001 and December 2008 were retrospectively reviewed. The failure patterns, prognostic factors, and efficacy of additional chemotherapy were assessed. RESULTS: The median follow-up time was 78 months for 298 patients. The 5-year local recurrence-free survival (LRFS), nodal recurrence-free survival (NRFS), distant metastasis-free survival (DMFS), failure-free survival (FFS), and overall survival (OS) were 95.2%, 99.3%, 94.8%, 89.8%, and 92.9%, respectively. The rate of treatment failure remained high in patients with T4 disease (35.4%, 17/48), including eight of local recurrence, two of nodal recurrence, and seven of distant metastasis. Multivariate analyses showed that the primary gross tumor volume (GTVp) was significantly associated with LRFS, DMFS, FFS, and OS. Subgroup analysis revealed that patients with GTVp ≤ 42.5 cc had better 5-year LRFS (98.7% vs 81.4%, P < .001), 5-year DMFS (97.8% vs 82.5%, P < .001), 5-year FFS (96.1% vs 65.4%, P < .001), and 5-year OS (96.6% vs 78.2%, P < .001) than patients with GTVp > 42.5 cc. However, additional chemotherapy showed no significant survival benefit in stratification analysis. CONCLUSIONS: Cervical node-negative NPC has a good prognosis in the IMRT era, and the primary tumor volume is the most important prognostic factor. Further exploration is needed to determine the optimal treatment strategy for patients with a high tumor burden.

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