Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 190
Filtrar
1.
Food Sci Nutr ; 9(10): 5590-5599, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34646529

RESUMO

Lipid accumulation is a major factor in the development of non-alcoholic fatty liver disease (NAFLD). Currently, there is a lack of intervention or therapeutic drugs against NAFLD. In this study, we investigated the ability of Sargassum fusiforme polysaccharide (SFPS) to reduce lipid accumulation induced by high sugar in HepG2 cells and Drosophila melanogaster larvae. The results indicated that SFPS significantly (p < .01) decreased the accumulation of lipid droplets in high sugar-induced HepG2 cells. Furthermore, SFPS also suppressed the expression of Srebp and Fas (genes involved in lipogenesis) and increased the expression of PPARɑ and Cpt1 (genes that participated in fatty acid ß-oxidation) in these cells. SFPS markedly reduced the content of triglyceride of the third instar larvae developed from D. melanogaster eggs reared on the high-sucrose diet. The expression of the Srebp and Fas genes in the larvae was also inhibited whereas the expression of two genes involved in the ß-oxidation of fatty acids, Acox57D-d and Fabp, was increased in the larval fat body (a functional homolog of the human liver). We also found that SFPS ameliorated developmental abnormalities induced by the high-sucrose diet. These results of this study suggest that SFPS could potentially be used as a therapeutic agent for the prevention and treatment of NAFLD.

2.
J Int Med Res ; 49(9): 3000605211038137, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34486433

RESUMO

Primary pulmonary high-grade mucoepidermoid carcinoma (MEC) with a cystic airspace is uncommon, and early metastasis is extremely rare. In such cases, however, it is clinically important for clinicians to consider whether the tumor has spread to the lymph nodes through the cystic airspace. A 77-year-old man presented to our hospital with cough and hemoptysis. Chest computed tomography showed a 25-mm-diameter mass with a cystic airspace located in the upper lobe of the left lung. The possibility of malignancy was considered. Without a definitive preoperative diagnosis, left upper lobectomy and mediastinal lymphadenectomy were performed. Histopathological examination revealed the typical histological characteristics of high-grade MEC (stage IA) and no lymph node metastasis. However, lymph node metastasis was found 6 months after surgical resection, and radiochemotherapy was performed. The patient developed widespread metastatic disease 4 months following completion of radiochemotherapy and died 2 months later. Primary pulmonary MEC with a cystic airspace is a rare malignant disease with uncommon imaging findings. Complete surgical resection is the main treatment method for high-grade MEC. In this case, we hypothesize that early metastasis was caused by seeding of tumor cells through the cystic airspace.


Assuntos
Carcinoma Mucoepidermoide , Neoplasias Pulmonares , Idoso , Carcinoma Mucoepidermoide/diagnóstico por imagem , Carcinoma Mucoepidermoide/cirurgia , Humanos , Pulmão , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Excisão de Linfonodo , Metástase Linfática , Masculino
3.
Cladistics ; 37(5): 540-558, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34570937

RESUMO

The Sarcophagidae (flesh flies) comprise a large and widely distributed radiation within the Calyptratae (Diptera). Larval feeding habits are ecologically diverse and include sarcosaprophagy, coprophagy, herbivory, invertebrate and vertebrate predation, and kleptoparasitism. To elucidate the geographic origin and evolution of flesh fly life-history, we inferred a backbone phylogeny based on transcriptomic data from 26 sarcophagid species covering all three subfamilies plus 15 outgroups. The phylogeny was inferred using maximum parsimony and maximum likelihood methods based on a series of supermatrices, one set with overall information content improved by MARE (2290 loci), one set with 100% gene coverage for all included species (587 loci), and the last set including mitochondrial and nuclear genes (589 loci) and additional taxa. In order to obtain a more detailed hypothesis, we utilized the supertree approach to combine results from the present study with previously published hypotheses. This resulted supertree covers 84 of the one hundred currently recognized sarcophagid genera and formed the basis for the ancestral state reconstructions. The monophyletic Sarcophagidae is well-supported as sister to {Mystacinobiidae + Oestridae}, and relationships at the subfamily level are inferred as {Sarcophaginae, (Paramacronychiinae + Miltogramminae)}. The Sarcophagidae and each subfamily originated in the Americas, with Sarcophaginae diversifying mainly in the Neotropics, whereas the major radiation of both Miltogramminae and Paramacronychiinae occurred in the Palaearctic. Sarcosaprophagy is reconstructed as the ancestral larval feeding habit of the family Sarcophagidae and each subfamily. The ancestral sarcophagid larva probably utilized dead invertebrates as food, and the food spectrum expanded together with the diversification of breeding strategies. Particularly, kleptoparasitism in Miltogramminae is derived from sarcosaprophagy and may be seen as having derived from the breeding biology of 'lower' miltogrammines, the larvae of which feed on buried vertebrate carrion.

4.
Integr Zool ; 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34520120

RESUMO

Captive conditions can affect the symbiotic microbiome of animals. In this study, we compared the structural and functional differences of the gastrointestinal microbiomes of wild Bactrian camels (Camelus ferus) between wild and captive populations, as well as their different host energy utilization performances through metagenomics. The results showed that wild-living camels harbored more microbial taxa related to the production of volatile fatty acids, fewer methanogens, and fewer genes encoding enzymes involved in methanogenesis, leading to higher energy utilization efficiency compared to that of captive-living camels. These findings suggest that the wild-living camel fecal microbiome demonstrates a series of adaptive characteristics that enable the host to adjust to a relatively barren field environment. Our study provides novel insights into the mechanisms of wildlife adaptations to habitats from the perspective of the microbiome.

5.
Vet Parasitol ; 299: 109575, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34521041

RESUMO

We characterised, for the first time, the whole mitogenome of a unique tapeworm, Moniezia sichuanensis (Cyclophyllidea, Anoplocephalidae) of forest musk deer (Moschus berezovskii). The total length of the circular mitogenome was 13,652 bp. It consisted of 12 protein-coding genes (PCGs), 22 transfer RNA genes, and two ribosomal RNA genes, which are typical of the mitogenomes of Moniezia. By comparing the available mitogenomes of PCGs for Cyclophyllidea in GenBank, nad6 and cox1 showed the highest and lowest evolutionary rates, respectively, and cox2 could be used as a potential DNA barcoding marker. The phylogenetic analyses of Cyclophyllidea confirmed the monophyly of the genus Moniezia and the family Anoplocephalidae; they then formed a clade with species of Hymenolepididae. Moreover, two novel gene arrangements of Cyclophyllidea were observed.

6.
Virus Res ; 305: 198573, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34555436

RESUMO

The PB2 protein of avian influenza virus (AIV) is essential for transcription and replication of virus genome. In this study, we reported that chicken heterogenous nuclear riboncleoprotein AB (hnRNPAB) cooperated with avian influenza viral protein PB2 and inhibited the polymerase activity and virus replication. We found that hnRNPAB was associated with PB2 mRNA and overexpression of hnRNPAB reduced PB2 mRNA nuclear export and PB2 protein level, but had no influence on PB2 mRNA level. At the same time, overexpression of hnRNPAB also reduced protein levels rather than mRNA levels of PA, PB1 and NP. In addition, overexpression of hnRNPAB restricted the polymerase activity and virus replication, while knockdown of hnRNPAB resulted in enhanced polymerase activity and virus replication. Lastly, virus infection induced the nuclear accumulation of hnRNPAB, but did not cause the change of expression level of endogenous hnRNPAB in DF-1 cells. Collectively, these findings suggested that hnRNPAB played a restrictive role in polymerase activity and virus replication potentially through inhibiting PB2 mRNA nuclear export and PB2 protein level.

7.
Int J Parasitol Parasites Wildl ; 16: 70-74, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34458090

RESUMO

Myiasis is an infestation of maggots on living tissue in humans and animals all over the world. It is known to occur in wild animals, while no information is reported in forest musk deer (Moschus berezovskii). During our research on the conservation of forest musk deer, we found a new record of traumatic myiasis of an injured forest musk deer. The flies are likely Lucilia caesar (Linnaeus, 1758) according to the results of DNA barcoding technology. We report traumatic myiasis of forest musk deer for the first time, which expands the information on parasite and myiasis of forest musk deer and confirms the potential risk of traumatic myiasis of forest musk deer.

8.
ACS Appl Mater Interfaces ; 13(34): 40249-40266, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34424682

RESUMO

Disruption of intestinal homeostasis is an important event in the development of inflammatory bowel disease (IBD), and genistein (GEN) is a candidate medicine to prevent IBD. However, the clinical application of GEN is restricted owing to its low oral bioavailability. Herein, a reactive oxygen species (ROS)-responsive nanomaterial (defined as GEN-NP2) containing superoxidase dismutase-mimetic temporally conjugated ß-cyclodextrin and 4-(hydroxymethyl)phenylboronic acid pinacol ester-modified GEN was prepared. GEN-NP2 effectively delivered GEN to the inflammation site and protected GEN from rapid metabolism and elimination in the gastrointestinal tract. In response to high ROS levels, GEN was site-specifically released and accumulated at inflammatory sites. Mechanistically, GEN-NP2 effectively increased the expression of estrogen receptor ß (ERß), simultaneously reduced the expression of proinflammatory mediators (apoptosis-associated speck-like protein containing a CARD (ASC) and Caspase1-p20), attenuated the infiltration of inflammatory cells, promoted autophagy of intestinal epithelial cells, inhibited the secretion of interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α), modulated the gut microbiota, and ultimately alleviated colitis. In addition, the oral administration of these nanoparticles showed excellent safety, thereby providing confidence in the further development of precise treatments for IBD.

9.
Chem Biol Interact ; 347: 109616, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34363818

RESUMO

The reproductive toxicity of endocrine-disrupting chemicals has become a matter of great concern. However, the potential toxicological mechanism of typical environmental estrogens, bisphenol A (BPA) and genistein (GEN), on adult ovary remains ambiguous. In this study, we used laying hens as the experimental model and aimed to clarify the effect of long-term exposure to safe reference doses of BPA and GEN on adult ovary. Results demonstrated that 1/10 no-observable-adverse effect-level dose (1/10 NOAEL, 500 µg/kg body weight [bw]/day) of BPA significantly reduced the production performance and caused the degeneration of follicles and stromal cells and the increase of atretic follicles. Moreover, 1/10 NOAEL dose of BPA undermined the redox homeostasis of the ovary through activating Keap1 and suppressing the Nrf2-signaling pathway (Nrf2, NQO1, and HO-1). On the contrary, GEN (20, 40 mg/kg bw/day) dramatically improved the antioxidant capacity of the ovary by regulating the Nrf2-Keap1 pathway, enhancing the activities of antioxidant-related enzymes (CAT, GSH-Px, and T-SOD), and inhibiting the excessive accumulation of lipid peroxidation products (MDA). Parallel in vitro studies confirmed that the differential role of BPA and GEN on ovarian redox balance was directly mediated by Nrf2-Keap1 antioxidant system. And GEN could ameliorate BPA-induced oxidative stress. Importantly, our research found that exposure to BPA and GEN altered estrogen receptor alpha (ERα) expression in the ovary. And the use of specific ERα agonist/antagonist confirmed that BPA and GEN have opposite regulatory effects on the Nrf2-Keap1 pathway by targeting ERα.


Assuntos
Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Genisteína/toxicidade , Ovário/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fenóis/toxicidade , Transdução de Sinais/efeitos dos fármacos , Animais , Galinhas , Receptor alfa de Estrogênio/metabolismo , Feminino , Homeostase/efeitos dos fármacos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Ovário/metabolismo , Ovário/patologia
11.
Environ Pollut ; 288: 117795, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34274649

RESUMO

Bisphenol A (BPA) and genistein (GEN) are selective estrogen receptor modulators, which are involved in the occurrence and development of metabolic syndrome. However, their roles in non-alcoholic fatty liver disease (NAFLD) of laying hens have not been reported. Here, we investigated the effects of different concentrations of GEN and BPA on the NAFLD of laying hens. Results showed that GEN ameliorated the high-energy and low-protein diet (HELP)-induced NAFLD by improving pathological damage, hepatic steatosis, and insulin resistance and blocking the expression of NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome-related factors. By contrast, high dose of BPA could aggravate these changes with serious symptom of NAFLD and suppress the level of ERα in the liver considerably, while GEN could reverse this phenomenon in a dose-dependent manner. In general, our research shows that the protective effect of GEN on NAFLD aims to improve the metabolic disorders and inflammation closely connected to ERα, while BPA can inhibit the expression of ERα and exacerbate the symptom of NAFLD. In conclusion, we elucidate the opposing effects of GEN and BPA in NAFLD of laying hens, thus providing a potential mechanism related to ERα and inflammation.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Compostos Benzidrílicos/toxicidade , Galinhas , Feminino , Genisteína/toxicidade , Fígado , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Fenóis
12.
Drug Metab Dispos ; 49(10): 870-881, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34321251

RESUMO

Point mutations in isocitrate dehydrogenase 1 (IDH1) result in conversion of α-ketoglutarate to the oncometabolite, d-2-hydroxyglutarate (2-HG). Ivosidenib is a once daily (QD), orally available, potent, mutant isocitrate dehydrogenase 1 (mIDH1) inhibitor approved for the treatment of patients with relapsed or refractory acute myeloid leukemia (AML) and intensive chemotherapy-ineligible newly diagnosed AML, with a susceptible IDH1 mutation. We characterized the protein binding, metabolism, metabolites, cell permeability, and drug-drug interaction potential of ivosidenib in humans, monkeys, dogs, rats, and/or mice in in vitro experiments. In vivo pharmacokinetic (PK) profiling and assessment of drug distribution and excretion was undertaken in rats, dogs, and monkeys administered single-dose ivosidenib. The PK/pharmacodynamic (PD) relationship between ivosidenib and 2-HG was analyzed in an mIDH1 xenograft mouse model. Ivosidenib was well absorbed, showed low clearance, and moderate to long terminal half-life (5.3-18.5 hours) in rats, dogs, and monkeys. Brain to plasma exposure ratio was low (2.3%), plasma protein binding was high, and oxidative metabolism was the major elimination pathway. Ivosidenib had high cell permeability and was identified as a substrate for P-glycoprotein. There was moderate induction of cytochrome P450 (P450) enzymes CYP3A4 and CYP2B6 but minimal P450 inhibition or autoinduction. Tumor 2-HG reduction appeared to be dose- and drug-exposure-dependent. Ivosidenib showed a favorable PK profile in several animal species, along with a clear PK/PD relationship demonstrating 2-HG inhibition that translated well to patients with AML. SIGNIFICANCE STATEMENT: Ivosidenib is a mutant IDH1 (mIDH1) inhibitor approved for the treatment of certain patients with mIDH1 acute myeloid leukemia. In Sprague-Dawley rats, beagle dogs, and cynomolgus monkeys, ivosidenib demonstrated a favorable pharmacokinetic profile, and in female BALB/c mice showed clear dose- and exposure-dependent inhibition of the oncometabolite, d-2-hydroxyglutarate, which is present at abnormal levels in mIDH1 tumors. These findings led to the further development of ivosidenib and are consistent with data from patients with mIDH1 cancers and healthy participants.

13.
Dalton Trans ; 50(31): 10806-10810, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34291266

RESUMO

Fluoro(dialkyl)stannylenoid 2 exhibits unique reactivity towards ethynes with acetylenic hydrogen and those with trimethylsilyl groups, though the corresponding free dialkylstannylene 1 is inactive against those ethynes. Stannylenoid 2 reacts smoothly with gaseous ethyne and phenylethyne at room temperature, giving the corresponding diethynylstannanes, di(phenylethynyl)stannane 3 and diethynylstannane 6, respectively, in good yields with the concomitant evolution of H2. Trimethylsilyl-substituted ethynes such as 1-trimethylsilyl-(2-phenyl)ethyne and 1,2-bis(trimethylsilyl)ethyne react similarly to give 3 and bis(trimethylsilylethynyl)stannane 8, respectively. Rather unexpectedly, the reaction of 2 with (trimethylsilyl)ethyne affords 1,2-bis(ethenylstannyl)ethyne 7 in a good yield. The reactions of 2 with methyl and ethyl propynoates give the same products 4 and 5 as those obtained during the reaction of dialkylstannylene 1 without CsF. Pathways involving the nucleophilic attack of cesium acetylide to an ethyne-complexed stannylene were proposed, while the detailed mechanisms remain unknown. The structure of 7 was studied by single crystal X-ray diffraction analysis.

14.
Front Surg ; 8: 666389, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34124136

RESUMO

Epithelioid angiosarcoma arising in schwannoma is an extremely rare mesenchymal tumor that accounts for only 1 to 2% of all sarcomas. This type of tumor occurs in all parts of the body, most often in the skin and soft tissues and rarely in the mediastinum. The present study describes the case of an asymptomatic, 58-year-old male who presented with epithelioid angiosarcoma in the posterior mediastinum during a physical examination. Enhanced computed tomography of the chest revealed a 3.5 × 3.1-cm mass in the posterior mediastinum. Thoracoscopic mediastinal mass resection was performed under general anesthesia due to the possibility that the tumor was malignant. Pathological examination revealed the presence of angiosarcoma and schwannoma components. Immunohistochemical staining for cluster of differentiation (CD) 31, CD34, early growth response (EGR), vimentin, Sry-related HMG box (SOX)-10 and S-100 was strongly positive. The patient recovered and was discharged on postoperative day 5. Two months postsurgery, the patient returned for evaluation, and no evidence of tumor recurrence was observed.

15.
PeerJ ; 9: e11294, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33996279

RESUMO

Background: The mitochondrial genome (mitogenome) has been extensively used for phylogenetic and evolutionary analysis in Diptera, but the study of mitogenome is still scarce in the family Chironomidae. Methods: Here, the first complete mitochondrial genomes of four Chironomid species representing Diamesinae, Orthocladiinae, Prodiamesinae and Tanypodinae are presented. Coupled with published mitogenomes of two, a comparative mitochondrial genomic analysis between six subfamilies of Chironomidae was carried out. Results: Mitogenomes of Chironomidae are conserved in structure, each contains 37 typical genes and a control region, and all genes arrange the same gene order as the ancestral insect mitogenome. Nucleotide composition is highly biased, the control region displayed the highest A + T content. All protein coding genes are under purifying selection, and the ATP8 evolves at the fastest rate. In addition, the phylogenetic analysis covering six subfamilies within Chironomidae was conducted. The monophyly of Chironomidae is strongly supported. However, the topology of six subfamilies based on mitogenomes in this study is inconsistent with previous morphological and molecular studies. This may be due to the high mutation rate of the mitochondrial genetic markers within Chironomidae. Our results indicate that mitogenomes showed poor signals in phylogenetic reconstructions at the subfamily level of Chironomidae.

16.
Exp Ther Med ; 21(6): 645, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33968176

RESUMO

Osteosarcoma (OS) is the most common malignant bone tumor in teens. Non-coding RNA activated by DNA damage (NORAD), a long non-coding RNA (lncRNA), has been reported to be involved in cancer biology, although its role in OS remains largely unknown. In the present study reverse transcription-quantitative PCR (RT-qPCR) was used to determine the expression levels of NORAD and miR-155-5p in samples from patients with OS. OS cell lines (Saos-2 and U2OS) were used as cell models. The biological influence of NORAD on OS cells was studied in vitro using Cell Counting Kit-8 and Transwell assays. The interaction between NORAD and miR-155-5p was clarified by bioinformatics analysis, RT-qPCR, luciferase reporter assay and RNA immunoprecipitation. NORAD was significantly increased in OS samples in comparison with controls, while miR-155-5p was reduced. Knockdown of NORAD and transfection of miR-155-5p mimics markedly inhibited the viability, migration and invasion of OS cells. There was a negative correlation between NORAD and miR-155-5p expression levels in OS samples. Taken together, the results of the present study indicated that the NORAD/miR-155-5p axis played a crucial role in regulating the proliferation, migration and invasion of OS cells. It is hypothesized that NORAD and miR-155-5p may serve as potential novel therapeutic targets for OS management.

17.
Biodivers Data J ; 9: e64558, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33948101

RESUMO

Background: The bat fly genus Ascodipteron Adensamer, 1896 currently contains 15 species, all of which occur in tropical and subtropical areas of the Eastern Hemisphere. A new species of endoparasitic bat fly, Ascodipteron sanmingensis sp. nov., was collected from the Great Himalayan Leaf-nosed Bat, Hipposideros armiger (Hodgson, 1853), during ecological studies on bats in Fujian, China. New information: A new species, Ascodipteron sanmingensis sp. nov., is described, based on dealate neosomic females and is supported by molecular data from a 368 bp fragment of the cytochrome B (Cytb) gene. Habitus and diagnostic details, as well as the attachment sites on the host, are documented with photographs. A detailed comparison of the new species with related species is provided and the new species is accommodated in the most recent key to the world species of Ascodipteron.

18.
BMC Gastroenterol ; 21(1): 230, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34020603

RESUMO

BACKGROUND: The effect of time delay from diagnosis to surgery on the prognosis of elderly patients with liver cancer is not well known. We investigated the effect of surgical timing on the prognosis of elderly hepatocellular carcinoma patients undergoing surgical resection and constructed a Nomogram model to predict the overall survival of patients. METHODS: A retrospective analysis was performed on elderly patients with primary liver cancer after hepatectomy from 2012 to 2018. The effect of surgical timing on the prognosis of elderly patients with liver cancer was analyzed using the cut-off times of 18 days, 30 days, and 60 days. Cox was used to analyze the independent influencing factors of overall survival in patients, and a prognostic model was constructed. RESULTS: A total of 232 elderly hepatocellular carcinoma patients who underwent hepatectomy were enrolled in this study. The cut-off times of 18, 30, and 60 days were used. The duration of surgery had no significant effect on overall survival. Body Mass Index, Child-Pugh classification, Tumor size Max, and Length of stay were independent influencing factors for overall survival in the elderly Liver cancer patients after surgery. These factors combined with Liver cirrhosis and Venous tumor emboli were incorporated into a Nomogram. The nomogram was validated using the clinical data of the study patients, and exhibited better prediction for 1-year, 3-year, and 5-year overall survival. CONCLUSIONS: We demonstrated that the operative time has no significant effect on delayed operation in the elderly patients with hepatocellular carcinoma, and a moderate delay may benefit some patients. The constructed Nomogram model is a good predictor of overall survival in elderly patients with hepatectomy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Idoso , Carcinoma Hepatocelular/cirurgia , Hepatectomia , Humanos , Neoplasias Hepáticas/cirurgia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
19.
Mitochondrial DNA B Resour ; 6(3): 862-864, 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33796659

RESUMO

Hamaxiella brunnescens (Mesnil, 1967) (Diptera, Tachinidae) is a parasitic fly species and of great ecological importance in natural systems as parasitoids of herbivorous insects. The mitogenome of H. brunnescens was sequenced and analyzed here for the first time. The genome is 14,956 bp in length with high A + T content, which consists of 13 protein-coding, 22 tRNA, two rRNA genes, and a partial non-coding control region. The phylogenetic analyses support a monophyletic Tachinidae. The two subfamilies Exoristinae and Phasiinae are fully supported as monophyletic while Tachininae is inferred to be paraphyletic.

20.
Opt Express ; 29(6): 8344-8357, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33820282

RESUMO

Absolute distance measurement with laser interferometry has the advantages of high precision and traceability to the definition of meter but its accuracy is primarily limited by the phase demodulation. Among kinds of absolute distance interferometric measurements, the multi-wavelength interferometry is widely used but seriously limited by the generation of suitable synthetic wavelength and the stability of adopted synthetic wavelength. Inspired by the mechanical lever, we hereby establish a principle of laser interferometric wavelength leverage (LIWL) for absolute distance measurement. By keeping the phase difference in two single wavelengths constant, LIWL achieves the measurement of large distance with respect to synthetic wavelengths by detecting nanometer displacement with respect to a single wavelength. The merit of LIWL is eliminating the influence of phase demodulation error. And a dynamic-sideband locking method based on a high-frequency electro-optic modulator is proposed, which can flexibly and quickly generate variable synthetic wavelengths from tens of kilometer to millimeter with high stability. Experimental setup was constructed and absolute distance measurements were performed. Experimental results show that a measurement range of 100 m with residual error of less than 15 µm has been achieved by comparing the LIWL system and an incremental laser interferometer.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...