Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 103
Filtrar
1.
J Hered ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635970

RESUMO

Species conservation can be improved by knowledge of genetic diversity and demographic history. The Sichuan hill-partridge (Arborophila rufipectus, SP) is an endangered species endemic to the mountains in southwestern China. However, little is known about this species' genomic variation and demographic history. Here, we present a comprehensive whole-genome analysis of six SP individuals from the Laojunshan National Nature Reserve in Sichuan Province, China. We observe a relatively high genetic diversity and low level of recent inbreeding in the studied SP individuals. This suggests that the current population carries genetic variability that may benefit the long-term survival of this species, and that the present population may be larger than currently recognized. Analyses of demographic history showed that fluctuations in the effective population size of SP are inconsistent with changes of the historical climate. Strikingly, evidence from demographic modeling suggests SPs population decreased dramatically 15,100 years ago after the Last Glacial Maximum (LGM), possibly due to refugial isolation and later human interference. These results provide the first detailed and comprehensive genomic insights into genetic diversity, genomic inbreeding levels, and demographic history of the Sichuan hill-partridge, which are crucial for the conservation and management of this endangered species.

2.
Int J Cancer ; 152(8): 1648-1658, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36444498

RESUMO

Patients with biliary tract cancer (BTC) were associated with poor prognosis and limited therapeutic options after first-line therapy currently. In this study, we sought to evaluate the feasibility and tolerability of sintilimab plus anlotinib as the second-line treatment for patients with advanced BTC. Eligible patients had histologically confirmed locally advanced unresectable or metastatic BTC and failed after the first-line treatment were recruited. The primary endpoint was overall survival (OS). Simultaneously, association between clinical outcomes and genomic profiling and gut microbiome were explored to identify the potential biomarkers for this regimen. Twenty patients were consecutively enrolled and received study therapy. The trail met its primary endpoint with a median OS of 12.3 months (95% CI: 10.1-14.5). Only four (20%) patients were observed of the grade 3 treatment-related adverse events (TRAEs) and no grade 4 or 5 TRAEs were detected. Mutation of AGO2 was correlated with a significantly longer OS. Abundance of Proteobacteria was associated with inferior clinical response. Therefore, sintilimab plus anlotinib demonstrated encouraging anti-tumor activity with a tolerable safety profile and deserved to be investigated in larger randomized trials for patients with advanced BTC subsequently.


Assuntos
Neoplasias dos Ductos Biliares , Neoplasias do Sistema Biliar , Humanos , Estudos de Viabilidade , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias do Sistema Biliar/genética , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
3.
J Hered ; 114(6): 654-668, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37646645

RESUMO

The schizothoracine fishes, widely distributed in the Qinghai-Tibetan Plateau and its adjacent areas, are considered as ideal models for investigation of high-altitude adaptation. Schizophygopsis are one group of the highly specialized schizothoracine fishes, and the genetic basis for their high-altitude adaptation is poorly understood. In this study, we performed comparative genomics analyses to investigate the potential genetic mechanisms for high-altitude adaptation of Schizopygopsis malacanthus and Schizopygopsis pylzovi based on the chromosome-level genomes. Functional enrichment analysis revealed that many expanded gene families in Schizopygopsis were associated with immune response while many contracted gene families were functionally associated with olfaction. Among the 123 positively selected genes (PSGs), angpt2a was detected in HIF-1 signaling pathway and possibly related to the hypoxia adaptation of Schizopygopsis. Furthermore, two PSGs cox15 and ndufb10 were distributed in thermogenesis, and there was a Schizopygopsis-specific missense mutation in cox15 (Gln115Glu), which possibly contributed to the cold temperature adaptation of the Schizopygopsis. Kyoto Encyclopedia of Genes and Genomes enrichment of the PSGs revealed three significant pathways including metabolic pathways, cell cycle, and homologous recombination and Gene Ontology enrichment analysis of the PSGs revealed several categories associated with DNA repair, cellular response to DNA damage stimulus, and metabolic process. Chromosome-scale characterization of olfactory receptor (OR) repertoires indicated that Schizopygopsis had the least number of OR genes, and the OR gene contraction was possibly caused by the limited food variety and the environmental factors such as lower air pressure, lower humidity, and lower temperature. Our study will help expand our understanding of the potential adaptive mechanism of Schizopygopsis to cope with the high-altitude conditions.


Assuntos
Altitude , Cyprinidae , Animais , Filogenia , Cyprinidae/genética , Genoma , Cromossomos , Adaptação Fisiológica/genética , Tibet
4.
J Hered ; 114(2): 175-188, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36546409

RESUMO

The Tibetan partridge (Perdix hodgsoniae) is a widely distributed endemic species in high-altitude areas across the Tibetan Plateau where the hypoxia, lower temperature and high ultraviolet radiation are pivotal factors influencing survival. However, the underlying genetic adaptation of the Tibetan partridge to extreme environments remains uncertain due to limited genomic resources. Similarly, the phylogenetic position of Perdix within Phasianidae remains controversial due to lacking information. Consequently, we de novo assembled and annotated the whole genome of the Tibetan partridge. The genome size was 1.15 Gb with contig N50 of 3.70 Mb. A total of 202.30 Mb (17.61%) repetitive elements and 445,876 perfect microsatellites were identified. A total of 16,845 functionally annotated protein-coding genes were identified in the Tibetan partridge. Genomic phylogenetic analysis across 30 Galliformes species indicated a close relationship between Perdix and typical pheasants composed of Chrysolophus, Symaticus, Phasianus, Crossopilon, and Lophura. However, the phylogenetic relationship of (Perdix + (Chrysolophus + (Syrmaticus + other pheasants))) was different from those of (Perdix + (Syrmaticus + (Chrysolophus + other pheasants))) in previous studies. Comparative genomic results identified NFKB1 and CREBBP positively selected genes related to hypoxia with 3 and 2 Tibetan partridge-specific missense mutations, respectively. Expanded gene families were mainly associated with energy metabolism and steroid hydroxylase activity, meanwhile, contracted gene families were mainly related to immunity and olfactory perception. Our genomic data considerably contribute to the phylogeny of Perdix and the underlying adaptation strategies of the Tibetan partridge to a high-altitude environment.


Assuntos
Altitude , Galliformes , Animais , Filogenia , Tibet , Raios Ultravioleta , Galliformes/genética , Adaptação Fisiológica/genética , Hipóxia
5.
Appl Microbiol Biotechnol ; 107(5-6): 1887-1902, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36795140

RESUMO

Vibrio alginolyticus is an important foodborne pathogen that can infect both humans and marine animals and cause massive economic losses in aquaculture. Small noncoding RNAs (sRNAs) are emerging posttranscriptional regulators that affect bacterial physiology and pathological processes. In the present work, a new cell density-dependent sRNA, Qrr4, was characterized in V. alginolyticus based on a previously reported RNA-seq analysis and bioinformatics approach. The effects of Qrr4 actions on the physiology, virulence, and metabolism of V. alginolyticus were comprehensively investigated based on molecular biology and metabolomics approaches. The results showed that qrr4 deletion markedly inhibited growth, motility and extracellular protease activities. Additionally, nontargeted metabolism and lipidomics analyses revealed that qrr4 deletion induced significant disturbance of multiple metabolic pathways. The key metabolic remodelling that occurred in response to qrr4 deletion was found to involve phospholipid, nucleotide, carbohydrate and amino acid metabolic pathways, providing novel clues about a potential mechanism via which mutation of qrr4 could interfere with cellular energy homeostasis, modulate membrane phospholipid composition and inhibit nucleic acid and protein syntheses to regulate the motility, growth and virulence characteristics of V. alginolyticus. Overall, this study provides a comprehensive understanding of the regulatory roles of the new cell density-dependent sRNA Qrr4 in V. alginolyticus. KEY POINTS: • A novel cell density-dependent sRNA, Qrr4, was cloned in V. alginolyticus. •Qrr4 regulated growth and virulence factors of V. alginolyticus. • Phospholipid, nucleotide and energy metabolisms were modulated obviously by Qrr4.


Assuntos
Pequeno RNA não Traduzido , Vibrio alginolyticus , Animais , Humanos , Vibrio alginolyticus/genética , Virulência/genética , Fatores de Virulência/metabolismo , Nucleotídeos/metabolismo , Pequeno RNA não Traduzido/genética , Proteínas de Bactérias/genética
6.
Angew Chem Int Ed Engl ; 62(14): e202216977, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36753392

RESUMO

Post-synthetic modification (PSM) is an effective approach for the tailored functionalization of metal-organic architectures, but its generalizability remains challenging. Herein we report a general covalent PSM strategy to functionalize Pdn L2n metal-organic cages (MOCs, n=2, 12) through an efficient Diels-Alder cycloaddition between peripheral anthracene substituents and various functional motifs bearing a maleimide group. As expected, the solubility of functionalized Pd12 L24 in common solvents can be greatly improved. Interestingly, concentration-dependent circular dichroism and aggregation-induced emission are achieved with chiral binaphthol (BINOL)- and tetraphenylethylene-modified Pd12 L24 , respectively. Furthermore, Pd12 L24 can be introduced with two different functional groups (e.g., chiral BINOL and achiral pyrene) through a step-by-step PSM route to obtain chirality-induced circularly polarized luminescence. Moreover, similar results are readily observed with a smaller Pd2 L4 system.

7.
Angew Chem Int Ed Engl ; 62(50): e202315020, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37884445

RESUMO

The development of energy-saving technology for the efficient separation of olefin and paraffin is highly important for the chemical industry. Herein, we report a self-assembled Fe4 L6 capsule containing a hydrophobic cavity, which can be used to encapsulate and separate propylene/propane. The successful encapsulation of propylene and propane by the Fe4 L6 cage in a water solution was documented by NMR spectroscopy. The binding constants K for the Fe4 L6 cage toward propylene and propane were determined to be (5.0±0.1)×103  M-1 and (2.1±0.7)×104  M-1 in D2 O at 25 °C, respectively. Experiments and theoretical studies revealed that the cage exhibited multiple weak interactions with propylene and propane. The polymer-grade propylene (>99.5 %) can be obtained from a mixture of propylene and propane by using the Fe4 L6 cage as a separation material in a U-shaped glass tube. This work provides a new strategy for the separation of olefin/paraffin.

8.
Insect Mol Biol ; 31(4): 457-470, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35302262

RESUMO

Pederin, a group of antitumor compounds, is produced by an endosymbiotic bacterium of Paederus fuscipes. Pederin content differed between male and female P. fuscipes, but the reason why these differences are maintained remains unexplored. Here, the pederin-producing bacteria (PPB) infection rate in P. fuscipes was investigated. Furthermore, we assessed the microbiota structure differences in male and female P. fuscipes harbouring PPB and sequenced the transcriptome of both sexes to shed light on genes of interest. Of the 625 analysed beetles (275 females, 350 males), 96.36% of females and 31.14% of males were positive for PPB infection. PPB accounted for 54.36%-82.70% of the bacterial population in females but showed a much lower abundance in males (0.92%-3.87%). Reproductive organs possessed the highest PPB abundance compared with other parts of females, but no such relationships existed in males. Moreover, we provide the first transcriptome analysis of male and female P. fuscipes harbouring PPB and identified 8893 differentially expressed unigenes. Our results indicated that the pederin content difference between males and females might be caused by the PPB density difference in hosts. The biosequence data would be helpful for illustrating the mechanism that regulates PPB density in P. fuscipes.


Assuntos
Besouros , Microbiota , Animais , Bactérias/genética , Besouros/genética , Feminino , Masculino , Piranos , Transcriptoma
9.
Genetica ; 150(6): 355-366, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36287311

RESUMO

Short Tandem repeats (STRs) often occur within coding regions and adaptive selection could play a vital role in shaping the landscape of coding STRs. Here, we identified 849, 1282 and 1501 genes that contained 966, 1565 and 1921 STRs in the coding regions of the giant panda, polar bear and brown bear genomes, respectively. The results showed that coding STRs were subject to strong selection on STR type, motif, repetition and mode of evolution. Coding STRs were primarily found in regulatory genes. Of the three ursids studied, we found 585 differential genes in the giant panda. Gene Ontology analysis showed that the significant enrichment term (insulin-like growth factor receptor signaling pathway) exerted direct carbohydrate metabolic effects in vivo in this species. The enrichment of this pathway suggested that the giant panda's ability to absorb carbohydrates (starch) and adapt to a bamboo diet might be enhanced by variable coding STRs. We also identified 377 conserved coding STRs located in 377 genes across the three species. Kyoto Encyclopedia of Genes and Genomes enrichment analysis showed that these genes were significantly enriched in two pathway involved in key physiological processes, including cardiovascular function and energy metabolism regulation. This study provides an important resource for future studies on the regulation of rapid diet and environmental adaptation of species by coding STRs.


Assuntos
Ursidae , Animais , Ursidae/genética , Ursidae/metabolismo , Repetições de Microssatélites , Fases de Leitura Aberta , Genoma , Adaptação Fisiológica/genética
10.
Org Biomol Chem ; 20(35): 7011-7016, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36000782

RESUMO

Herein, an economical copper-catalyzed reaction of α,ß-unsaturated N-tosylhydrazones with diaryliodonium salts to construct both N-arylpyrazoles and diaryl sulfones has been developed. Both the p-toluenesulfonyl anion and the 3-arylpyrazole intermediates were formed in situ from N-tosylhydrazones. Subsequently, the former reacted rapidly with diaryliodonium salts to give diaryl sulfones and aryl iodide intermediates, and the latter reacted with aryl iodide to give N-arylpyrazoles under copper-catalyzed conditions. Using unsymmetrical mesityl phenyliodonium salts as substrates, mesityl p-toluenesulfide was obtained as the major product. This reaction took full advantage of the "waste" part of substrates to form an extra diaryl sulfone.


Assuntos
Cobre , Sais , Catálise , Iodetos , Sulfonas
11.
Arch Insect Biochem Physiol ; 111(4): e21956, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35933728

RESUMO

The synanthropic pest and a model organism for entomological research, American cockroach, Periplaneta americana (Linnaeus), can survive in unfavorable environments for humans. To investigate the genetic mechanisms of success in environmental adaptation of P. americana, we de novo reassembled its whole genome based on next-generation sequencing and PacBio sequencing. The final genome reassembly consisted of approximately 3.34 Gb with scaffold N50 of 465.51 Kb. The completeness (95.4%) of the complete genome was evaluated with single-copy orthologous genes using BUSCO. We identified 18,618 protein-coding genes, 16,443 (88.32%) of which were well supported by public protein databases. We identified 482.04 Mb (approximately 14.45%) repeat elements, 1,385,093 perfect microsatellites simple sequence repeats in P. americana genome, which was higher than other four Blattaria insects. Comparative genomics analysis revealed obvious expansion in the gene families associated with chemoreception (olfactory receptors, gustatory receptors, ionotropic glutamate receptors, chemosensory protein, and sensory neuron membrane protein), which provided the necessary information for functional characterization of the chemosensory receptors of P. americana, with potential for new or refined applications of semiochemicals-based control of this pest insect. Similarly, gene families (cytochrome P450s, carboxyl/choline esterases, and UDP-glycosyl-transferases) encoding receptors for bitter or toxic substances and detoxification enzymes were obviously expanded in P. americana, enabling its ability to detect and detoxify many toxins. Enrichment analysis of positively selected genes in P. americana revealed items associated with metabolic process and catalytic activity, which possibly contributed to the pesticide resistance of P. americana. We also analyzed the homologs to antimicrobial peptide genes reported in the Drosophila genome, and identified two attacins and seven defensins in P. americana. Our data and findings will substantially facilitate molecular studies in P. americana, including elucidation of detoxification mechanisms of xenobiotic, as well as development of new pest management strategies for the control of pests like P. americana.


Assuntos
Periplaneta , Receptores Odorantes , Animais , Alérgenos/metabolismo , Genoma , Sequenciamento de Nucleotídeos em Larga Escala , Periplaneta/metabolismo , Receptores Odorantes/genética , Análise de Sequência de DNA
12.
Mol Genet Genomics ; 295(1): 31-46, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31414227

RESUMO

The buff-throated partridge (Tetraophasis szechenyii) is a hypoxia-tolerant bird living in an extremely inhospitable high-altitude environment, which has high ultraviolet (UV) radiation as well as a low oxygen supply when compared with low-altitude areas. To further understand the molecular genetic mechanisms of the high-altitude adaptation of the buff-throated partridges, we de novo assembled the complete genome of the buff-throated partridge. Comparative genomics revealed that positively selected hypoxia-related genes in the buff-throated partridge were distributed in the HIF-1 signaling pathway (map04066), response to hypoxia (GO:0001666), response to oxygen-containing compound (GO:1901700), ATP binding (GO:0005524), and angiogenesis (GO:0001525). Of these positively selected hypoxia-related genes, one positively selected gene (LONP1) had one buff-throated partridge-specific missense mutation which was classified as deleterious by PolyPhen-2. Moreover, positively selected genes in the buff-throated partridge were enriched in cellular response to DNA damage stimulus (corrected P value: 0.028006) and DNA repair (corrected P value: 0.044549), which was related to the increased exposure of the buff-throated partridge to UV radiation. Compared with other avian genomes, the buff-throated partridge showed expansion in genes associated with steroid hormone receptor activity and contractions in genes related to immune and olfactory perception. Furthermore, comparisons between the buff-throated partridge genome and red junglefowl genome revealed a conserved genome structure and provided strong evidence of the sibling relationship between Tetraophasis and Lophophorus. Our data and analysis contributed to the study of Phasianidae evolutionary history and provided new insights into the potential adaptation mechanisms to the high altitude employed by the buff-throated partridge.


Assuntos
Adaptação Fisiológica/genética , Aves/genética , Altitude , Animais , Evolução Biológica , Genoma/genética , Estudo de Associação Genômica Ampla/métodos , Hipóxia/genética , Masculino , Seleção Genética/genética
13.
Mol Genet Genomics ; 294(3): 679-692, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30834967

RESUMO

Cathartidae is a small family of large-bodied carrion-feeding birds, of which the turkey vulture (Cathartes aura, Cathartidae) is the most widespread distributed. To investigate the chemoreception system, detoxification system, and immune system in the turkey vulture, we compared its genome to 14 other avian genomes. Comparative genomics demonstrated the expansion in the chemoreception system, especially the olfactory receptors, while the genes in the detoxification system of the turkey vulture did not show apparent expansion. We identified five positively selected genes associated with the immune system in the turkey vulture, which was likely to strengthen the immune defense against pathogenic invasion. Functional enrichment analysis indicated that many positively selected genes were involved in the regulation of immune system processes, implying important reorganization of the immune system in the turkey vulture. The turkey vulture-specific missense mutations were found in one positively selected gene (BCL6), and all the missense mutations were classified as deleterious by PolyPhen-2, possibly contributing to immune adaptation to the carrion feeding. Furthermore, we identified four turkey vulture-specific missense mutations in three ß-defensin genes of the turkey vulture, which was an indispensable part in the innate immunity (a natural barrier against invasive microbes including bacteria, fungi, and viruses). Our genomic analyses in the turkey vulture provided insights into the genetic signatures of the adaptation to the carrion feeding.


Assuntos
Proteínas Aviárias/genética , Aves/genética , Genoma/genética , Genômica/métodos , Sequência de Aminoácidos , Animais , Bactérias/patogenicidade , Aves/classificação , Aves/microbiologia , Comportamento Alimentar , Fungos/patogenicidade , Sistema Imunitário/metabolismo , Sistema Imunitário/microbiologia , Filogenia , Homologia de Sequência de Aminoácidos , Virulência , Vírus/patogenicidade , beta-Defensinas/genética
14.
Anticancer Drugs ; 30(9): 925-932, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31517732

RESUMO

Hypoxia has crucial roles in cancer development and progression. Our previous study indicated that cell migration was increased in a hypoxic microenvironment in GBC-SD gallbladder cancer (GBC) cells. Oridonin, a bioactive diterpenoid compound that is isolated from the plant Rabdosia rubescens, has been identified as an anticancer agent in various types of cancer. However, its roles in cell proliferation, apoptosis, and migration in a hypoxic microenvironment and the associated regulatory mechanisms have not yet to be fully elucidated in GBC. The present study investigated the effect of oridonin on cell proliferation, apoptosis, the cell cycle and cell migration in GBC in vitro and in vivo. Furthermore, the role of oridonin in hypoxia-induced cell migration and its underlying mechanisms were explored in GBC. The results indicated that treatment with oridonin significantly suppressed cell proliferation and the metastatic ability of GBC-SD cells in a dose-dependent manner, increased the level of cell apoptosis and induced cell cycle arrest at the G0/G1 phase. Further experiments demonstrated that oridonin could inhibit hypoxia-induced epithelial-mesenchymal transition and cell migration by downregulating the expression levels of hypoxia-inducible factor (HIF)-1α/matrix metallopeptidase (MMP)-9. In addition, oridonin suppressed GBC cell growth and downregulated the expression levels of HIF-1α and MMP-9 in a GBC-SD cell xenograft model. Taken together, these results suggest that oridonin possesses anticancer properties in GBC. Notably, oridonin can suppress tumor epithelial-mesenchymal transition and cell migration by targeting the HIF-1α/MMP-9 signaling pathway.


Assuntos
Movimento Celular/efeitos dos fármacos , Diterpenos do Tipo Caurano/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias da Vesícula Biliar/tratamento farmacológico , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/tratamento farmacológico , Metaloproteinase 9 da Matriz/metabolismo , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Feminino , Neoplasias da Vesícula Biliar/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Hipóxia/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
15.
Org Biomol Chem ; 17(37): 8561-8570, 2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31513227

RESUMO

An efficient method for the synthesis of N-sec-alkylpyrazoles through a base-promoted cascade cyclization/Michael addition reaction of α,ß-unsaturated N-tosylhydrazones with ortho-hydroxybenzyl alcohols has been developed. The desired products containing di- or triaryl groups at the same carbon atom were afforded in good to excellent yields with excellent regioselectivities (>20 : 1). Moreover, a three-component reaction of ortho-hydroxybenzyl alcohols, α,ß-unsaturated N-tosylhydrazones and saturated N-tosylhydrazones also took place to afford pyrazoles in good yields. This reaction offers a new route to triarylmethanes with a simple operation and is applicable for large-scale synthesis.

16.
Sensors (Basel) ; 19(8)2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31027253

RESUMO

A self-sensing and self-actuating quartz tuning fork (QTF) can be used to obtain its frequency shift as function of the tip-sample distance. Once the function of the frequency shift versus force gradient is acquired, the combination of these two functions results in the relationship between the force gradient and the tip-sample distance. Integrating the force gradient once and twice elucidates the values of the interaction force and the interatomic potential, respectively. However, getting the frequency shift as a function of the force gradient requires a physical model which can describe the equations of motion properly. Most papers have adopted the single harmonic oscillator model, but encountered the problem of determining the spring constant. Their methods of finding the spring constant are very controversial in the research community and full of discrepancies. By circumventing the determination of the spring constant, we propose a method which models the prongs and proof mass as elastic bodies. Through the use of Hamilton's principle, we can obtain the equations of motion of the QTF, which is subject to Lennard-Jones potential force. Solving these equations of motion analytically, we get the relationship between the frequency shift and force gradient.

17.
Int J Mol Sci ; 20(19)2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31590392

RESUMO

The American cockroach (Periplaneta americana) is a medicinal insect. Its extract is used clinically to promote wound healing and tissue regeneration, but the effective medicinal components and mechanisms are not yet clear. It has been reported that human thymosin beta 4 (Tß4) may accelerate skin wound healing, however, the role of P. americana thymosin (Pa-THYs) is still poorly understood. In the present study, we identify and analyze the DNA sequences of Pa-THYs by bioinformatics analysis. Then we clone, express, and purify the Pa-THYs proteins and evaluate the activity of recombinant Pa-THYs proteins by cell migration and proliferation assays in NIH/3T3 cells. To elucidate the role of Pa-THYs in wound healing, a mouse model is established, and we evaluate wound contraction, histopathological parameters, and the expressions of several key growth factors after Pa-THYs treatment. Our results showed that three THY variants were formed by skipping splicing of exons. Pa-THYs could promote fibroblast migration, but have no effect on fibroblast proliferation. In wound repair, Pa-THYs proteins could effectively promote wound healing through stimulating dermal tissue regeneration, angiogenesis, and collagen deposition. On the molecular mechanism, Pa-THYs also stimulated the expression of several key growth factors to promote wound healing. The data suggest that Pa-THYs could be a potential drug for promoting wound repair.


Assuntos
Baratas/genética , Proteínas de Insetos/farmacologia , Timosina/farmacologia , Cicatrização/efeitos dos fármacos , Células 3T3 , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Clonagem Molecular , Baratas/metabolismo , Proteínas de Insetos/genética , Masculino , Camundongos , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Timosina/genética
18.
Cell Physiol Biochem ; 42(1): 222-230, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28535506

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNAs) have been shown to play important roles in a wide range of pathophysiological processes, including cancer progression. Our previous study has shown that AFAP1-AS1 was upregulated and acted as an oncogene in hepatocellular carcinoma. However, the expression and biological functions of lncRNA AFAP1-AS1 in intrahepatic cholangiocarcinoma (CCA) remains largely unknown. METHODS: The expression level of AFAP1-AS1 was measured in 56 pairs of human cholangiocarcinoma tumor tissues and corresponding adjacent normal bile duct tissues. The correlation between AFAP1-AS1 and the clinicopathological features were evaluated by chi-square test. The effects of AFAP1-AS1 on CCA cells were determined by CCK-8 assay, clone formation assay, flow cytometry and transwell assay. Finally, to determine the effect of AFAP1-AS1 on tumor growth in vivo, AFAP1-AS1 knockdowned CCLP-1 cells were subcutaneously into nude mice to evaluate tumor growth. RESULTS: In this study, we found that lncRNA AFAP1-AS1 was increased in CCA tissues and patients with high AFAP1-AS1 expression had a shorter overall survival. SiRNA-mediated AFAP1-AS1 knockdown significantly decreased cell proliferation of the CCA cells, with downregulation of C-myc and Cycling D1 in vitro. Furthermore, AFAP1-AS1 silencing inhibited cell migration partly due to decrease the expression of MMP-2 and MMP-9. In addition, CCLP-1 cells with AFAP1-AS1 knockdown were injected into nude mice to investigate the effect of AFAP1-AS1 on the tumorigenesis in vivo. CONCLUSIONS: Taken together, our findings suggested that AFAP1-AS1 might promote the CCA progression and provided a novel potential therapeutic target for CCA.


Assuntos
Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/patologia , RNA Longo não Codificante/metabolismo , Animais , Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/mortalidade , Carcinogênese , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Colangiocarcinoma/metabolismo , Colangiocarcinoma/mortalidade , Progressão da Doença , Regulação para Baixo , Feminino , Humanos , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Interferência de RNA , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/genética , RNA Interferente Pequeno/metabolismo , Transplante Heterólogo
19.
J Asian Nat Prod Res ; 19(9): 884-889, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27802774

RESUMO

The EtOH extract of the roots and rhizomes of Clematis mandshurica afforded two new lignans clemomanshurinane C (1) and clemomanshurinane D (2), and three known compounds (3-5). Their structures were elucidated on the basis of spectroscopic means and hydrolysis products. All compounds displayed moderate inhibitory activity against enzyme lipoxygenase.


Assuntos
Clematis/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Lignanas/isolamento & purificação , Lignanas/farmacologia , Inibidores de Lipoxigenase/isolamento & purificação , Inibidores de Lipoxigenase/farmacologia , Medicamentos de Ervas Chinesas/química , Lignanas/química , Inibidores de Lipoxigenase/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/química , Rizoma/química
20.
Tumour Biol ; 37(7): 9699-707, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26803513

RESUMO

Increasing evidence has indicated that dysregulation of long non-coding RNAs (lncRNAs) can contribute to the progression and metastasis of human cancer, including HCC. Previous studies have shown that the lncRNA AFAP1-AS1 plays a critical role in cancer. However, the roles of AFAP1-AS1 in HCC remain to be determined. In the present study, AFAP1-AS1 was found to be increased in HCC tissues, and high AFAP1-AS1 expression was associated with tumor size, TNM stage, vascular invasion, and poor prognosis. Silencing of AFAP1-AS1 significantly reduced cell proliferation, clonal growth, cell migration, and invasion and increased apoptosis in vitro. Furthermore, AFAP1-AS1 silencing markedly reduced tumor growth in a murine allograft model in vivo. The results suggested that AFAP1-AS1 is important in HCC development and serves as a therapeutic target of HCC.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/secundário , Movimento Celular , Proliferação de Células , Neoplasias Pulmonares/patologia , RNA Longo não Codificante/genética , Animais , Apoptose , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Estudos de Casos e Controles , Progressão da Doença , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Metástase Linfática , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA