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1.
Int Immunopharmacol ; 80: 106144, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31927507

RESUMO

NLRP3 inflammasome may serve as a potential target for the development of novel therapeutics for inflammatory bowel diseases. In this study, we found that Libertellenone M (Lib M), a secondary metabolite from the endophytic fungus Phomopsis sp. S12, has anti-inflammatory potential both in vitro and in vivo. Lib M selectively inhibited the expression of proinflammatory cytokine IL-1ß and IL-18 in LPS-activated macrophages. The cleavage of pro-caspase 1 was remarkably reduced by Lib M in macrophages stimulated with three NLRP3 inflammasome activators. Administering Lib M attenuated dextran sulfate sodium-induced experimental acute colitis in mice and significantly reduced the production of these cytokines and cleaved caspase 1 in colon tissues. Apart from inhibition of NLRP3 inflammasome assembly, Lib M also suppressed NF-κB nuclear translocation in macrophages. Taken together, these findings suggest that Lib M-mediated inhibition of NLRP3 inflammasome activation could protect against colitis-like inflammatory diseases, and that this compound derived from a plant-associated fungus might inspire the exploration of novel immunosuppressive agents.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31950220

RESUMO

Fatty acid-binding protein 2 (Fabp2), which is involved in the transport of long-chain fatty acids, is widely studied in mammals. Nevertheless, the role of this protein in teleost fish is mostly unknown. Here, we produced a fabp2-/- zebrafish (KO) animal model. Compared with wild-type zebrafish (WT), KO had a markedly decreased content of intestinal n-3 poly-unsaturated fatty acids (n-3 PUFAs) and increased levels of intestinal, hepatic, and serum triacylglycerols (TAG). The intestinal transcriptome analysis of KO and WT revealed an obviously disrupted TAG metabolism and up-regulated bile secretion in KO. Expression levels of the genes related to fatty acid transport and cholesterol (CL) absorption in the intestine of KO were significantly lower than those of WT, while the expression levels of genes related to intestinal TAG synthesis and hepatic CL synthesis were in the opposite direction. To confirm these findings, we further established fabp2 transgenic zebrafish (TG). Compared with WT, TG had a markedly increased content of intestinal n-3 PUFAs, a significantly decreased level of hepatic TAG, and significantly higher expression of genes related to fatty acid transport and CL absorption in the intestine. In conclusion, this study suggests that teleost fish fabp2 could promote intestinal n-3 PUFA absorption to mediate TAG synthesis and CL homeostasis, by regulating the genes involved in lipid metabolism.

3.
Oncol Res ; 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31907106

RESUMO

Cancer cell stemness is responsible for cancer relapse, distal metastasis, and drug resistance. Herewe identified that Frizzled 2 (Fzd2), one member of Wnt receptor Frizzled family, induced humanbreast cancer (BC) cell stemness via non-canonical Wnt pathways. Fzd2 was overexpressed inhuman BC tissues, and Fzd2 overexpression was associated with an unfavorable outcome. Fzd2knockdown (KD) disturbed the mesenchymal-like phenotype, migration and invasion of BC cells.Moreover, Fzd2 KD impaired BC cell mammosphere formation, reduced Lgr5+ BC cellsubpopulation, and enhanced sensitivity of BC cells to chemical agents. Mechanistically, Fzd2modulated and bound with Wnt5a/b and Wnt3 to activate several oncogenic pathways such as IL-6/Stat3, Yap1 and TGF-ß1/Smad3. These data indicate that Fzd2 contributes to BC cellmesenchymal-like stemness; targeting Fzd2 may inhibit BC recurrence, metastasis andchemoresistance.

4.
Int J Biol Sci ; 16(2): 194-203, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929748

RESUMO

Ruxolitinib is a selective inhibitor of Jak1/2. Downstream signaling pathways of Jak, such as Stat3 and Akt/mTOR, are overactivated and contribute to renal interstitial fibrosis. Therefore, we explored the effect of Ruxolitinib on this pathological process. Unilateral ureteral obstruction (UUO) models and TGF-ß1-treated fibroblasts and renal tubular epithelial cells were adopted in this study. Ruxolitinib was administered to UUO mice and TGF-ß1-treated cells. Kidneys from UUO mice with Ruxolitinib treatment displayed less tubular injuries compared with those without Ruxolitinib treatment. Ruxolitinib treatment suppressed fibroblast activation and extracellular matrix (ECM) production in UUO kidneys and TGF-ß1-treated fibroblasts. Ruxolitinib treatment also blocked epithelial-mesenchymal transition (EMT) in UUO kidneys and TGF-ß 1-treated renal tubular epithelial cells. Moreover, Ruxolitinib treatment alleviated UUO-induced inflammation, oxidative stress and apoptosis. Mechanistically, Ruxolitinib treatment attenuated activation of both Stat3 and Akt/mTOR/Yap pathways. In conclusion, Ruxolitinib treatment can ameliorate UUO-induced renal interstitial fibrosis, suggesting that Ruxolitinib may be potentially used to treat fibrotic kidney disease.

5.
Eur J Med Chem ; 187: 111971, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31881457

RESUMO

For the purpose of advancing our research on diverse C-20 decorated derivatives of camptothecin (CPT), 46 new CPT acylthiourea derivatives were synthesized and evaluated in vitro for their cytotoxicity. All the compounds showed promising in vitro cytotoxicity against six tumor cell lines (Hep3B, MCF7, A549, MDA-MB-231, KB and KB-vin). Out of them, compound c20 possesses remarkable in vitro cytotoxic activity and is more potent than topotecan. Mechanistically, c20 not only induces cell cycle arrest and cell apoptosis in A549 cells, but also inhibits Topo I activity in the cell and cell-free system in a manner similar to that of topotecan. In both xenograft and primary HCC mouse models, c20 displays significant in vivo anti-cancer activity and is more potent than topotecan. In addition, the acute toxicity assay showed that c20 has no apparent toxicity to mouse liver, kidney and hemopoietic system of the FVB/N mice. Take together, these results indicated that compound c20 could be a potential anti-cancer candidate for further clinical trial.

6.
Biomacromolecules ; 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31851512

RESUMO

Self-assembled peptide nanofibers have been widely studied in cancer nanotherapeutics with their excellent biocompatibility and low toxicity of degradation products, showing the significant potential in inhibiting tumor progression. However, poor solubility prevents direct intravenous administration of nanofibers. Although water-soluble peptide precursors have been formed via the method of phosphorylation for intravenous administration, their opportunities for broad in vivo application are limited by the weak capacity of encapsulating drugs. Herein, we designed a novel restructured reduced glutathione (GSH)-responsive drug delivery system encapsulating doxorubicin for systemic administration, which achieved the intracellular restructuration from three-dimensional micelles into one-dimensional nanofibers. After a long blood circulation, micelles endocytosed by tumor cells could degrade in response to high GSH levels, achieving more release and accumulation of doxorubicin at desired sites. Further, the synergistic chemotherapy effects of self-assembled nanofibers were confirmed in both in vitro and in vivo experiments.

7.
Cancer Sci ; 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31830330

RESUMO

Patients with triple-negative breast cancer (TNBC) lack molecular targets and have an unfavorable outcome. CD155 is overexpressed in human cancers, but whether it plays a role in TNBC is unexplored. Here we found that CD155 was enriched in both TNBC cell lines and tumor tissues. High CD155 expression was related to poor prognosis of breast cancer patients. CD155 was associated with a mesenchymal phenotype. CD155 knockdown induced a mesenchymal-epithelial transition (MET) in TNBC cells, and suppressed TNBC cell migration, invasion and metastasis in vitro and in vivo. Mechanistically, CD155 cross-talked with oncogenic IL-6/Stat3 and TGF-ß/Smad3 pathways. Moreover, CD155 knockdown inhibited TNBC cell growth and survival. Taken together, these data indicate that CD155 contributes to the aggressive behavior of TNBC; targeting CD155 may be beneficial to these patients.

8.
Sheng Li Xue Bao ; 71(6): 839-845, 2019 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-31879739

RESUMO

The purpose of this study was to explore the effects of calcitonin gene-related peptide (CGRP) on the long-term depression (LTD) of hippocampus in mice. Sixty C57BL/6J mice (30 days old) were randomly divided into control group, three CGRP (50, 100, and 200 nmol/L) groups, CGRP + CGRP8-37 group and CGRP + APV group (10 mice for each group). The effects of exogenous application of different concentrations of CGRP on synaptic plasticity and LTD in hippocampus of mice were detected by in vitro recording of local field potential. The results showed that higher doses (100 and 200 nmol/L) of CGRP significantly enhanced the induction of LTD in the hippocampus. Moreover, CGRP increased the magnitude of N-methyl-D-aspartate (NMDA) receptor-mediated excitatory postsynaptic currents. The above-mentioned effects of CGRP were blocked by either CGRP selective antagonist CGRP8-37 or NMDA receptor antagonist APV. These results suggest that CGRP can dose-dependently enhance the induction of LTD in hippocampus of mice, and the underlying mechanism involves the mediation of NMDA receptor function.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina , Hipocampo , Animais , Peptídeo Relacionado com Gene de Calcitonina/farmacologia , Hipocampo/efeitos dos fármacos , Depressão Sináptica de Longo Prazo/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória
9.
Adv Mater ; : e1907005, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31850657

RESUMO

Microsized supercapacitors (mSCs) with small volume, rapid charge-discharge rate, and ultralong cyclic lifetime are urgently needed to meet the demand of miniaturized portable electronic devices. A versatile self-shrinkage assembling (SSA) strategy to directly construct the compact mSCs (CmSCs) from hydrogels of reduced graphene oxide is reported. A single CmSC is only 0.0023 cm3 in volume, which is significantly smaller than most reported mSCs in fiber/yarn and planar interdigital forms. It exhibits a high capacitance of up to 68.3 F cm-3 and a superior cycling stability with 98% capacitance retention after 25 000 cycles. Most importantly, the SSA technique enables the CmSC as the building block to realize arbitrary, programmable, and multi-dimensional integration for adaptable and complicated power systems. By design on mortise and tenon joint connection, autologous integrated 3D interdigital CmSCs are fabricated in a self-holding-on manner, which thus dramatically reduces the whole device volume to achieve the high-performance capacitive behavior. Consequently, the SSA technique offers a universal and versatile approach for large-scale on-demand integration of mSCs as flexible and transformable power sources.

10.
Huan Jing Ke Xue ; 40(12): 5202-5212, 2019 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854590

RESUMO

To study the composition characteristics and source apportionment of PM2.5 in the eastern part of the North China Plain, manual samples during the two-year heating period of 2016 and 2017 were collected in seven cities, including Hengshui, Cangzhou, Ji'nan, Dezhou, Binzhou, Zibo, and Liaocheng. The results showed that the average values of ρ(PM2.5) during the observation periods were 137.23 µg·m-3 and 111.83 µg·m-3, respectively, which exceeded the daily average secondary standard limit of GB 3095-2012 "Environmental Air Quality Standard" by 1.8 and 1.5 times, respectively. The mean mass of water-soluble ions accounted for 53.32% and 47.04% of ρ(PM2.5), respectively, of which SNA (NO3-, SO42-, and NH4+) were the main ions. During the 2016 and 2017 observation periods, NO3-/SO42- increased from 1.35 to 1.60, while the concentration of Cl- decreased, indicating a decrease in the impact of coal burning. The proportions of secondary organic carbon (SOC) in organic carbon (OC) were 71.63% and 55.35%, respectively, indicating the source of secondary organic carbon had decreased. Analysis of characteristic elements Fe/Al and Ba/Ni showed that dust sources and vehicle sources had increased significantly. The backward trajectories of air mass results showed that the polluted air mass mainly came from the northwest direction during the observation period. However, the PM2.5 concentration was highest when the air mass came from the Anhui and Jiangsu provinces.

11.
Comput Math Methods Med ; 2019: 4830914, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31885681

RESUMO

In recent years, we have seen more and more interest in the field of medical images and shape comparison motivated by the latest advances in microcomputed tomography (µCT) acquisition, modelling, and visualization technologies. Usually, biologists need to evaluate the effect of different root canal preparation systems. Current root canal preparation evaluation methods are based on the volume difference, area difference, and transportation of two root canals before and after treatment. The purpose of root canal preparation is to minimize the volume difference and ensure the complete removal of the smear layer. Previous methods can reflect some general geometric differences, but they are not enough to evaluate the quality of root canal shape. To solve this problem, we proposed a novel root canal evaluation method based on spectrum and eigenfunctions of Steklov operators, which can be served as a better alternative to current methods in root canal preparation evaluation. Firstly, the ideal root canal model was simulated according to the root canal model before and after preparation. Secondly, the Steklov spectrum of the two models was calculated. Thirdly, based on the spectrum and the histogram of the Gaussian curvature on the surface, the weight of each eigenvalue was computed. Therefore, the Steklov spectrum distance (SSD), which measures shape difference between the root canals, was defined. Finally, the calculation method that quantifies the root canal preparation effect of root canals was obtained. Through experiments, our method manifested high robustness and accuracy compared with existing state-of-the-art approaches. It also demonstrates the significance of our algorithm's advantages on a variety of challenging root canals through result comparison with counterpart methods.

12.
Biomed Res Int ; 2019: 4242304, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31886212

RESUMO

Background: Neck circumference (NC) was found to be related to the risk factors of cardiovascular disease. However, the effects of NC on cardiovascular disease are still controversial. A prospective study of Chinese patients with type 2 diabetes was performed to evaluate the relationship between NC and cardiovascular disease. Methods: A multicenter prospective study with eight-year follow-up was conducted in Beijing communities. Cardiovascular events were defined as myocardial infarction, unstable angina pectoris, hospitalization for heart failure, coronary revascularization, cardiac death, stroke, transient ischemic attack, and cerebral hemorrhage. Results: A total of 3,009 diabetic patients were recruited. Following an eight-year follow-up, 211 patients with cardiovascular events (105 in men and 106 in women) were identified. All patients were categorized into two groups according to the upper quartile of NC (43 cm in men and 39 cm in women). The prevalence of cardiovascular events in men with an NC >43 cm (16.48%) was higher than that in the group with an NC <43 cm (8.16%, p=0.007). The prevalence of cardiovascular events in women with the NC >39 cm (10.67%) was higher compared to the group with NC <39 cm (5.31%, p=0.004). The longitudinal prevalence of cardiovascular events in groups with different NC increased with the increasing duration of follow-up (p < 0.001). Cox regression analysis showed that higher NC was associated with the occurrence of cardiovascular events after adjusting for confounding variables (adjusted HR = 2.305 (1.535-3.460)). Conclusions: NC was associated with the occurrence of cardiovascular events in type 2 diabetes in Chinese communities, and greater NC may increase the risk of cardiovascular events by about 2.3-fold.

13.
Opt Express ; 27(23): 34192-34203, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31878472

RESUMO

Large heterodyne receiver arrays (~100 pixel) allow astronomical instrumentations to map more area within limited space mission lifetime. One challenge is to generate multiple local oscillator (LO) beams. Here, we succeeded in generating 81 beams at 3.86 THz by combining a reflective, metallic Fourier grating with an unidirectional antenna coupled 3rd-order distributed feedback (DFB) quantum cascade laser (QCL). We have measured the diffracted 81 beams by scanning a single pyroelectric detector at a plane, which is in the far field for the diffraction beams. The measured output beam pattern agrees well with a simulated result from COMSOL Multiphysics, with respect to the angular distribution and power distribution among the 81 beams. We also derived the diffraction efficiency to be 94 ± 3%, which is very close to what was simulated for a manufactured Fourier grating (97%). For an array of equal superconducting hot electron bolometer mixers, 64 out of 81 beams can pump the HEB mixers with similar power, resulting in receiver sensitivities within 10%. Such a combination of a Fourier grating and a QCL can create an LO with 100 beams or more, enabling a new generation of large heterodyne arrays for astronomical instrumentation.

14.
Cell Death Dis ; 10(12): 957, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31862870

RESUMO

Radiation-induced lung injury (RILI) is one of the most common and fatal complications of thoracic radiotherapy, whereas no effective interventions are available. Andrographolide, an active component extracted from Andrographis paniculate, is prescribed as a treatment for upper respiratory tract infection. Here we report the potential radioprotective effect and mechanism of Andrographolide on RILI. C57BL/6 mice were exposed to 18 Gy of whole thorax irradiation, followed by intraperitoneal injection of Andrographolide every other day for 4 weeks. Andrographolide significantly ameliorated radiation-induced lung tissue damage, inflammatory cell infiltration, and pro-inflammatory cytokine release in the early phase and progressive fibrosis in the late phase. Moreover, Andrographolide markedly hampered radiation-induced activation of the AIM2 inflammasome and pyroptosis in vivo. Furthermore, bone marrow-derived macrophages (BMDMs) were exposed to 8 Gy of X-ray radiation in vitro and Andrographolide significantly inhibited AIM2 inflammasome mediated-pyroptosis in BMDMs. Mechanistically, Andrographolide effectively prevented AIM2 from translocating into the nucleus to sense DNA damage induced by radiation or chemotherapeutic agents in BMDMs. Taken together, Andrographolide ameliorates RILI by suppressing AIM2 inflammasome mediated-pyroptosis in macrophage, identifying Andrographolide as a novel potential protective agent for RILI.

15.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(6): 631-635, 2019 Dec 01.
Artigo em Chinês | MEDLINE | ID: mdl-31875442

RESUMO

OBJECTIVE: This study aimed to investigate the value of normalized iodine concentration (NIC), spectral attenuation curve slope (SACS), area under curve (AUC), and iodine concentration difference (ICD) generated from spectral CT in the assessment of parotid gland tumors. METHODS: Ninety-two patients with pathologically confirmed parotid gland tumors underwent arterial phase- and venous phase-enhanced CT in spectral CT. The patients were divided into the pleomor-phic adenoma group (group A), Warthin tumor group (group B), basal cell tumor group (group C), and malignant tumor group (group D). The SACS, AUC, NIC, ICD were measured and analyzed. Statistical analyses were performed by one-way ANOVA, and statistical significance was set at P<0.05. RESULTS: SACS(AP), AUC(AP), and NIC(AP) in group A were lower than those in other groups; SACS(VP) and AUC(VP) in group C were higher than those in other groups; NIC(AP) and NIC(VP) in group D were higher than those in other groups; and ICD in group B was a positive number. The difference in SACS(AP) and AUC(AP) in groups B and C, SACS(VP) and AUC(VP) in groups C and D, and ICD in groups A and C were not statistically significant. By contrast, the diffe-rence between the other groups was statistically significant (P<0.05). The difference in NIC(AP) between groups A and B and groups C and D and the difference in NIC(VP) between groups A and C, groups A and D, and groups B and C were statistically significant (P=0.005, 0.025, 0.002, 0.038, and 0.049, respectively). CONCLUSIONS: Multi-quantitative parameters from spectral CT might be helpful in differentiating various types of parotid gland tumors.


Assuntos
Iodo , Tomografia Computadorizada por Raios X , Diagnóstico Diferencial , Humanos , Glândula Parótida
16.
Proc Natl Acad Sci U S A ; 116(49): 24463-24469, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31740599

RESUMO

From 2013 to 2017, with the implementation of the toughest-ever clean air policy in China, significant declines in fine particle (PM2.5) concentrations occurred nationwide. Here we estimate the drivers of the improved PM2.5 air quality and the associated health benefits in China from 2013 to 2017 based on a measure-specific integrated evaluation approach, which combines a bottom-up emission inventory, a chemical transport model, and epidemiological exposure-response functions. The estimated national population-weighted annual mean PM2.5 concentrations decreased from 61.8 (95%CI: 53.3-70.0) to 42.0 µg/m3 (95% CI: 35.7-48.6) in 5 y, with dominant contributions from anthropogenic emission abatements. Although interannual meteorological variations could significantly alter PM2.5 concentrations, the corresponding effects on the 5-y trends were relatively small. The measure-by-measure evaluation indicated that strengthening industrial emission standards (power plants and emission-intensive industrial sectors), upgrades on industrial boilers, phasing out outdated industrial capacities, and promoting clean fuels in the residential sector were major effective measures in reducing PM2.5 pollution and health burdens. These measures were estimated to contribute to 6.6- (95% CI: 5.9-7.1), 4.4- (95% CI: 3.8-4.9), 2.8- (95% CI: 2.5-3.0), and 2.2- (95% CI: 2.0-2.5) µg/m3 declines in the national PM2.5 concentration in 2017, respectively, and further reduced PM2.5-attributable excess deaths by 0.37 million (95% CI: 0.35-0.39), or 92% of the total avoided deaths. Our study confirms the effectiveness of China's recent clean air actions, and the measure-by-measure evaluation provides insights into future clean air policy making in China and in other developing and polluting countries.

18.
Int J Mol Sci ; 20(21)2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31671637

RESUMO

Based on the up-regulation of the proviral integration site of the Moloney murine leukemia virus (Pim) kinase family (Pim1, 2, and 3) observed in several types of leukemias and lymphomas, the development of pan-Pim inhibitors is an attractive therapeutic strategy. While only PIM447 and AZD1208 have entered the clinical stages. To elucidate the interaction mechanisms of three Pim kinases with PIM447 and AZD1208, six Pim/ligand systems were studied by homology modeling, molecular docking, molecular dynamics (MD) simulation and molecular mechanics/generalized Born surface area (MM/GBSA) binding free energy calculation. The residues of the top group (Leu44, Val52, Ala65, Lys67, and Leu120 in Pim1) dominated the pan-Pim inhibitors binding to Pim kinases. The residues of the bottom group (Gln127, Asp128, and Leu174 in Pim1) were crucial for Pims/PIM447 systems, while the contributions of these residues were decreased sharply for Pims/AZD1208 systems. It is likely that the more potent pan-Pim inhibitors should be bound strongly to the top and bottom groups. The residues of the left, right and loop groups were located in the loop regions of the binding pocket, however, the flexibility of these regions triggered the protein interacting with diverse pan-Pim inhibitors efficiently. We hope this work can provide valuable information for the design of novel pan-Pim inhibitors in the future.

19.
Biotech Histochem ; : 1-9, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31762324

RESUMO

Chromosome spreads are important for complex molecular cytogenetic studies. An adequate chromosome spreading method for identification and isolation of the maize B chromosome, however, has not been reported. We used the maize inbred lines, B73 and Mo17, the hybrid YD08 line and the landrace DP76 to develop an optimized chromosome spreading method. We investigated the effects of four treatment factors on the quality of metaphase chromosome spreads using a factorial analysis of variance. Optimal conditions for metaphase spreading were identified using regression analysis based on multifactor orthogonal design of four treatment factors with five levels for each factor. We developed optimal conditions for metaphase spreading as follows: nitrous oxide treatment for 2 h, glacial acetic acid fixation for 2 h, enzyme hydrolysis for 6.0 h, and a drop height of 35 cm for cell suspension. We obtained high quality metaphase chromosome spreads with large metaphase areas, large numbers of chromosomes, few chromosome overlaps and high frequency of intact metaphases. Our optimized drop-slide procedure was markedly better than the traditional flame smear technique. We identified 487 B chromosomes in three forms from maize landraces from Southwest China. We found no relation between the C-band number and B chromosome. Single B chromosomes also were isolated directly from a metaphase chromosome drop-slide using a micromanipulator. Our optimized method provides a simple, efficient and reproducible procedure for preparing high quality plant chromosome spreads.

20.
Zootaxa ; 4623(1): zootaxa.4623.1.7, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31716277

RESUMO

The Hirtodrosophila melanderi species group is currently known for thirteen described species, most of which were thought to be fungivorous. More than half known species of this species group were recorded exclusively from high altitude zone to the southeast of the Qinghai-Tibet Plateau in China. In our recent field survey in the Huanglong National Nature Reserve (located to the east of the Qinghai-Tibet Plateau) in Sichuan Province, China, we collected dozens of specimens of the H. melanderi group there. In the present study, these specimens are subjected to species delimitation based on data of not only morphology, but also DNA barcodes (nucleotide sequences of a 658-bp fragment of the mitochondrial cytochrome c oxidase subunit I gene). The five new species thus recognized are described: Hirtodrosophila minshanensis sp. nov., H. lambda sp. nov., H. zhangae sp. nov., H. zouae sp. nov., and H. nigrispina sp. nov. In addition, an updated key to all species of the H. melanderi species group is provided.


Assuntos
Dípteros , Drosophilidae , Animais , China , Genes Mitocondriais , Filogenia , Tibet
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