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Small bowel adenocarcinoma (SBA), particularly duodenal adenocarcinoma (DA), is a rare gastrointestinal cancer with a dismal prognosis. Data on SBA treatments are limited, and the therapeutic strategy remains uncertain. Currently, chemotherapy is the most used treatment; however, it has a poor median progression-free survival (mPFS) of no more than five months in the second-line setting. We report a case with DA that responded well to the immune checkpoint inhibitor (ICI) tislelizumab plus irinotecan in the second-line treatment. To our knowledge, this is the first report of administering ICIs plus chemotherapy to SBA. Despite the absence of microsatellite instability-high (MSI-H) and high tumor mutational burden (TMB), the patient with TP53/KRAS mutation achieved a significantly long PFS of 17 months, and the benefit is still ongoing. The mechanism of this remarkable efficacy might be associated with an increase in tumor immunogenicity after chemotherapy. The current study presents a promising effect of ICIs plus chemotherapy on SBA, affirming the need to investigate the clinical value of this combination in SBA and the underlying mechanism behind it.
Assuntos
Adenocarcinoma , Inibidores de Checkpoint Imunológico , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Biomarcadores Tumorais/genética , Adenocarcinoma/genética , Instabilidade de Microssatélites , MutaçãoRESUMO
To establish a multidimensional nomogram model for predicting progression-free survival (PFS) and risk stratification in patients with advanced nasopharyngeal carcinoma (NPC). This retrospective cross-sectional study included 156 patients with advanced NPC who underwent dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Radiomic features were extracted from the efflux rate constant (Ktrans ) and extracellular extravascular volume (Ve ) mapping derived from DCE-MRI. Least absolute shrinkage and selection operator (LASSO) Cox regression analysis was applied for feature selection. The Radscore was constructed using the selected features with their respective weights in the LASSO Cox regression analysis. A nomogram model combining the Radscore and clinical factors was built using multivariate Cox regression analysis. The C-index was used to assess the discrimination power of the Radscore and nomogram. The Kaplan-Meier method was used for survival analysis. Of the 360 radiomic features, 28 were selected (7, 6, and 15 features extracted from Ktrans , Ve, and Ktrans +Ve images, respectively). The combined Radscore k trans +Ve (C-index, 0.703, 95% confidence interval [CI]: 0.571-0.836) showed higher efficacy in predicting the prognosis of advanced NPC than Radscore k trans (C-index, 0.693; 95% CI, 0.560-0.826) and Radscore Ve (C-index, 0.614; 95% CI, 0.481-0.746) did. Multivariable Cox regression analysis revealed clinical stage, T stage, and treatment with nimotuzumab as risk factors for PFS. The nomogram established by Radscore k trans +Ve and risk factors (C-index, 0.732; 95% CI: 0.599-0.864) was better than Radscore k trans +Ve in predicting PFS in patients with advanced NPC. A lower Radscore k trans +Ve (HR 3.5584, 95% CI 2.1341-5.933), lower clinical stage (hazard ratio [HR] 1.5982, 95% CI 0.5262-4.854), lower T stage (HR 1.4365, 95% CI 0.6745-3.060), and nimotuzumab (NTZ) treatment (HR 0.7879, 95% CI 0.4899-1.267) were associated with longer PFS. Kaplan-Meier analysis showed a lower PFS in the high-risk group than in the low-risk group (p<0.0001). The nomogram based on combined pretreatment DCE-MRI radiomics features, NTZ, and clinicopathological risk factors may be considered as a noninvasive imaging marker for predicting individual PFS in patients with advanced NPC.
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Chinese medicinal injection, made of active components extracted from Chinese medicine or Chinese medicinal compound, is a novel dosage form of Chinese patent medicine in China and is pivotal in the traditional Chinese medicine(TCM) industry. The quality control standard of Chinese medicinal injection determines its safety and efficacy. The quantitative nuclear magnetic resonance(qNMR) spectroscopy is a non-targeted, non-invasive, and non-destructive technique with high reproducibility, short measurement time, convenient sample preparation, a broad range of linearity, and no requirement on the reference substance of tested components, which is advantageous as compared with traditional chromatographic methods, and it can provide information about the molecular composition of the tested samples. Therefore, in light of multiple challenges in the quality control of Chinese medicinal injection, such as complex composition, difficulties in quantitative analysis, and the shortage of reference substances, the application of qNMR spectroscopy combined with chemometrics techniques was proposed for the quality evaluation of Chinese medicine reference substances, Chinese medicinal injection, and intermediates in the production process, as well as for the stability analysis of Chinese medicinal injection. This study is expected to provide references for the application of qNMR spectroscopy in the quality control of Chinese medicinal injection.
Assuntos
Medicina Tradicional Chinesa , Controle de Qualidade , Espectroscopia de Ressonância Magnética , Reprodutibilidade dos TestesRESUMO
The present study established a quality evaluation method for ginsenoside reference substances based on quantitative nuclear magnetic resonance(qNMR) spectroscopy. ~1H-NMR spectra were collected on Bruker Avance â ¢ 500 MHz NMR spectrometer equipped with a 5 mm BBO probe. The acquire parameters were set up as follows: pulse sequence of 30°, D_1=20 s, probe temperature= 303 K, and the scan number = 32. Dimethyl terephthalate, a high-quality ~1H-qNMR standard, was used as the internal standard and measured by the absolute quantitative method. Methyl peaks of comparatively good sensitivity were selected for quantification, and linear fitting deconvolution was adopted to improve the accuracy of integration results. The qNMR spectroscopy-based method was established and validated, which was then used for the quality evaluation of ginsenoside Rg_1, ginsenoside Re, ginsenoside Rb_1, ginsenoside Rd, and notoginsenoside R_1. The results suggested that the content of these ginsenoside reference standards obtained from the qNMR spectroscopy-based method was lower than that detected by the normalization method in HPLC provided by the manufacturers. In conclusion, the qNMR spectroscopy-based method can ensure the quality of ginsenoside reference substances and provide powerful support for the accurate quality evaluation of Chinese medicine and its preparations. The qNMR spectroscopy-based method is simple, rapid, and accurate, which can be developed for the quantitative assay of Chinese medicine standard references.
Assuntos
Ginsenosídeos , Cromatografia Líquida de Alta Pressão/métodos , Ginsenosídeos/análise , Espectroscopia de Ressonância Magnética/métodos , Espectroscopia de Prótons por Ressonância Magnética , Padrões de ReferênciaRESUMO
Shenmai Injection is a Chinese medicinal injection prepared from Ginseng Radix et Rhizoma Rubra and Ophiopogonis Radix, which is widely used in clinical practice for the treatment and adjuvant therapy of cardiovascular diseases with significant pharmacological effects. Proton nuclear magnetic resonance spectroscopy(~1H-NMR) has the advantages of simple and nondestructive sample pretreatment, fast analysis, abundant chemical information, quantification and no need to follow the standard curve. It is widely used in the analysis and research of complex mixtures of traditional Chinese medicine, clinical blood and urine samples. In this study, the ~1H-NMR fingerprint of Shenmai Injection was established. Thirty-two chemical components were identified, including seven amino acids, eight small molecular organic acids, one alkaloid, four sugars, two nucleosides, seven saponins, and three other components. Pearson's correlation coefficient and multivariate analysis of variance(principal component analysis combined with hierarchical cluster analysis) were applied based on the ~1H-NMR fingerprint to evaluate the quality consistency. The results showed high-quality consistency of 82 batches of Shenmai Injection. This study confirms that the ~1H-NMR fingerprint has great potential in the application of quality control of Chinese medicinal injection.
Assuntos
Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/química , Espectroscopia de Prótons por Ressonância Magnética , Rizoma/químicaRESUMO
A content determination method based on ~1H-qNMR was developed for the determination of total ginsenosides in Shenmai Injection. The parameters were optimized with CD_3OD as the solvent, dimethyl terephthalate as the internal standard, the peak at δ 8.11 as the internal standard peak, and the peaks at δ 1.68 and δ 0.79 as quantitative peaks of total ginsenosides. The developed ~1H-qNMR-based method was validated methodologically. The results showed that the method could achieve accurate measurement of total ginsenosides in Shenmai Injection in the range of 0.167 6-3.091 1 mmol·L~(-1). The developed ~1H-qNMR-based method for total ginsenosides is simple in operation, short in analysis time, strong in specificity, independent of accompanying standard curve, and small in sample volume, which can serve as a reliable mean for the quality control of Shenmai Injection. This study is expected to provide new ideas for the development of quantification methods of total ginsenosides.
Assuntos
Medicamentos de Ervas Chinesas , Ginsenosídeos , Combinação de Medicamentos , Ginsenosídeos/análise , Controle de QualidadeRESUMO
Danhong Injection, a compound Chinese medicine injection prepared from Salviae Miltiorrhizae Radix et Rhizoma and Carthami Flos, is used in the clinical treatment of coronary heart disease, cerebral thrombosis, myocardial infarction, angina pectoris and other cardiovascular and cerebrovascular diseases. In this study, a quantitative method for simultaneous determination of multiple components in Danhong Injection was developed based on ~1H-qNMR technology and then methodological verification was carried out. The results showed that the established method had good methodological indexes. This method can simultaneously determine the content of 21 chemical components including 6 amino acids, 4 small molecular organic acids, 5 sugars and their derivatives, 1 nucleoside, and 5 aromatic compounds in Danhong Injection. The total content accounted for about 85% of the total solid mass, which reflected the great advantage of ~1H-qNMR method in the analysis of Chinese medicine injections. The ~1H-qNMR method for simultaneous determination of multiple components in Danhong Injection developed in this study has simple operation, short analysis time, and wide application range, which has practical significance for the quality evaluation of Danhong Injection and provides reference for the development of quality control methods for Chinese medicine injections.
Assuntos
Medicamentos de Ervas Chinesas , Infarto do Miocárdio , Humanos , Medicamentos de Ervas Chinesas/química , Medicina Tradicional Chinesa , Infarto do Miocárdio/tratamento farmacológico , Controle de QualidadeRESUMO
BACKGROUND: Altica (Coleoptera: Chrysomelidae) is a highly diverse and taxonomically challenging flea beetle genus that has been used to address questions related to host plant specialization, reproductive isolation, and ecological speciation. To further evolutionary studies in this interesting group, here we present a draft genome of a representative specialist, Altica viridicyanea, the first Alticinae genome reported thus far. RESULTS: The genome is 864.8 Mb and consists of 4490 scaffolds with a N50 size of 557 kb, which covered 98.6% complete and 0.4% partial insect Benchmarking Universal Single-Copy Orthologs. Repetitive sequences accounted for 62.9% of the assembly, and a total of 17,730 protein-coding gene models and 2462 non-coding RNA models were predicted. To provide insight into host plant specialization of this monophagous species, we examined the key gene families involved in chemosensation, detoxification of plant secondary chemistry, and plant cell wall-degradation. CONCLUSIONS: The genome assembled in this work provides an important resource for further studies on host plant adaptation and functionally affiliated genes. Moreover, this work also opens the way for comparative genomics studies among closely related Altica species, which may provide insight into the molecular evolutionary processes that occur during ecological speciation.
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Besouros , Sifonápteros , Animais , Besouros/genética , Evolução Molecular , Genoma , GenômicaRESUMO
BACKGROUND: High incidence of asymptomatic venous thromboembolism (VTE) has been observed in severe COVID-19 patients, but the characteristics of symptomatic VTE in general COVID-19 patients have not been described. OBJECTIVES: To comprehensively explore the prevalence and reliable risk prediction for VTE in COVID-19 patients. METHODS/RESULTS: This retrospective study enrolled all COVID-19 patients with a subsequent VTE in 16 centers in China from January 1 to March 31, 2020. A total of 2779 patients were confirmed with COVID-19. In comparison to 23,434 non-COVID-19 medical inpatients, the odds ratios (ORs) for developing symptomatic VTE in severe and non-severe hospitalized COVID-19 patients were 5.94 (95% confidence interval [CI] 3.91-10.09) and 2.79 (95% CI 1.43-5.60), respectively. When 104 VTE cases and 208 non-VTE cases were compared, pulmonary embolism cases had a higher rate for in-hospital death (OR 6.74, 95% CI 2.18-20.81). VTE developed at a median of 21 days (interquartile range 13.25-31) since onset. Independent factors for VTE were advancing age, cancer, longer interval from symptom onset to admission, lower fibrinogen and higher D-dimer on admission, and D-dimer increment (DI) ≥1.5-fold; of these, DI ≥1.5-fold had the most significant association (OR 14.18, 95% CI 6.25-32.18, p = 2.23 × 10-10 ). A novel model consisting of three simple coagulation variables (fibrinogen and D-dimer levels on admission, and DI ≥1.5-fold) showed good prediction for symptomatic VTE (area under the curve 0.865, 95% CI 0.822-0.907, sensitivity 0.930, specificity 0.710). CONCLUSIONS: There is an excess risk of VTE in hospitalized COVID-19 patients. This novel model can aid early identification of patients who are at high risk for VTE.
Assuntos
Biomarcadores/sangue , COVID-19/complicações , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Tromboembolia Venosa/diagnóstico , Trombose Venosa/epidemiologia , Idoso , COVID-19/sangue , COVID-19/diagnóstico , COVID-19/terapia , China/epidemiologia , Feminino , Mortalidade Hospitalar , Humanos , Imunização Passiva , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2 , Tromboembolia Venosa/sangue , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Trombose Venosa/sangue , Trombose Venosa/etiologia , Soroterapia para COVID-19RESUMO
Host plant shifts are a common mode of speciation in herbivorous insects. Although insects can evolve adaptations to successfully incorporate a new host plant, it is becoming increasingly recognized that the gut bacterial community may play a significant role in allowing insects to detoxify novel plant chemical defenses. Here, we examined differences in gut bacterial communities between Altica flea beetle species that feed on phylogenetically unrelated host plants in sympatry. We surveyed the gut bacterial communities of three closely related flea beetles from multiple locations using 16S rRNA amplicon sequencing. The results showed that the beetle species shared a high proportion (80.7%) of operational taxonomic units. Alpha-diversity indicators suggested that gut bacterial diversity did not differ among host species, whereas geography had a significant effect on bacterial diversity. In contrast, analyses of beta-diversity showed significant differences in gut bacterial composition among beetle species when we used species composition and relative abundance metrics, but there was no difference in composition when species presence/absence and phylogenetic distance indices were used. Within host beetle species, gut bacterial composition varied significantly among sites. A metagenomic functionality analysis predicted that the gut microbes had functions involved in xenobiotic biodegradation and metabolism as well as metabolism of terpenoids and polyketides. These predictions, however, did not differ among beetle host species. Antibiotic curing experiments showed that development time was significantly prolonged, and there was a significant decline in body weight of newly emerged adults in beetles lacking gut bacteria, suggesting the beetles may receive a potential benefit from the gut microbe-insect interaction. On the whole, our results suggest that although the gut bacterial community did not show clear host-specific patterns among Altica species, spatiotemporal variability is an important determinant of gut bacterial communities. Furthermore, the similarity of communities among these beetle species suggests that microbial facilitation may not be a determinant of host plant shifts in Altica.
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Fenômenos Fisiológicos Bacterianos , Besouros/microbiologia , Microbioma Gastrointestinal , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , Besouros/fisiologia , Feminino , Masculino , Metagenoma , RNA Bacteriano/análise , RNA Ribossômico 16S/análiseRESUMO
In the fission yeast Schizosaccharomyces pombe, both RNAi machinery and RNAi-independent factors mediate transcriptional and posttranscriptional silencing and heterochromatin formation. Here, we show that the silencing of reporter genes at major native heterochromatic loci (centromeres, telomeres, mating-type locus and rDNA regions) and an artificially induced heterochromatin locus is alleviated in a fission yeast hsp90 mutant, hsp90-G84C Also, H3K9me2 enrichment at heterochromatin regions, especially at the mating-type locus and subtelomeres, is compromised, suggesting heterochromatin assembly defects. We further discovered that Hsp90 is required for stabilization or assembly of the RNA-induced transcriptional silencing (RITS) and Argonaute siRNA chaperone (ARC) RNAi effector complexes, the RNAi-independent factor Fft3, the shelterin complex subunit Poz1 and the Snf2/HDAC-containing repressor complex (SHREC). Our ChIP data suggest that Hsp90 regulates the efficient recruitment of the methyltransferase/ubiquitin ligase complex CLRC by shelterin to chromosome ends and targeting of the SHREC and Fft3 to mating type locus and/or rDNA region. Finally, our genetic analyses demonstrated that increased heterochromatin spreading restores silencing at subtelomeres in the hsp90-G84C mutant. Thus, this work uncovers a conserved factor critical for promoting RNAi-dependent and -independent heterochromatin assembly and gene silencing through stabilizing multiple effectors and effector complexes.
Assuntos
Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Montagem e Desmontagem da Cromatina , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Heterocromatina/genética , Interferência de RNA , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/metabolismoRESUMO
BACKGROUND: Membrane-associated fibrinogen-like protein 2 (FGL2 prothrombinase, pFGL2) is abundantly expressed in activated microvascular endothelial cells (MVECs) and plays a crucial role in microthrombus formation in microcirculatory vasculature. It has been widely reported that coronary microvascular obstruction (CMVO) contributes to adverse outcomes following myocardial ischemia/reperfusion. However, the role of pFGL2 in CMVO is poorly understood. METHODS AND RESULTS: We aimed to identify the effect of MVECs-pFGL2 in CMVO using FGL2 knockout mice. As results, the MVECs-pFGL2 expression progresses significantly over 3â¯days and then gradually decreases, which is positively correlated with the extent of CMVO as detected by HE staining in wild type mice. Furthermore, FGL2 deficiency is correlated with decreased areas of no-reflow and necrosis as detected by Evans Blue and TTC staining and that it ameliorates cardiac dysfunction detected by hemodynamics in the early stage of CMVO. Moreover, fibrin deposition in microvasculature is significantly reduced in FGL2-deficient mice as evidenced by immunohistochemistry, MSB and Carstairs staining, along with the down-regulation of leukocyte adhesion and infiltration. Additionally, we observed that the FGL2 deficiency decreases macrophage infiltration and shifts the macrophage phenotype from pro-inflammatory (M1,) to anti-inflammatory (M2,) pattern in the early stage of CMVO. CONCLUSION: These findings highlight the MVECs-pFGL2-fibrin pathway in the early stage of CMVO and provide insights into coagulation and inflammation for the coronary artery disease therapeutics.
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Coagulação Sanguínea/fisiologia , Circulação Coronária/fisiologia , Oclusão Coronária/metabolismo , Vasos Coronários/metabolismo , Endotélio Vascular/metabolismo , Fibrina/metabolismo , Fibrinogênio/biossíntese , Animais , Western Blotting , Oclusão Coronária/patologia , Oclusão Coronária/fisiopatologia , Vasos Coronários/patologia , Modelos Animais de Doenças , Endotélio Vascular/patologia , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microcirculação , Fatores de TempoRESUMO
Coronary artery disease (CAD) is a multifactorial disease in which inflammation plays a central role. This study aimed to investigate the association of inflammatory markers such as the neutrophil to lymphocyte ratio (NLR), the Global Registry of Acute Coronary Events (GRACE) score with in-hospital mortality of elderly patients with acute myocardial infarction (AMI) in an attempt to explore the prognostic value of these indices for elderly AMI patients. One thousand consecutive CAD patients were divided into two groups based on age 60. The laboratory and clinical characteristics were assessed retrospectively by reviewing the medical records. The NLR and GRACE score were calculated. In the elderly (≥60 years), patients with non-ST-elevation myocardial infarction (NSTEMI) and ST-elevation myocardial infarction (STEMI) had significantly higher NLR than did those with unstable angina (UA) and stable angina pectoris (SAP) (P<0.01). The NLR was considerably elevated in older AMI patients compared with their younger counterparts (<60 years) (P<0.05). In elderly AMI patients, the NLR was considerably higher in the high-risk group than in both the low-risk and medium-risk groups based on the GRACE score (P<0.05 and P<0.01, respectively), and the NLR was positively correlated with the GRACE score (r=0.322, P<0.001). Either the NLR level or the GRACE score was significantly higher in the death group than in the surviving group (P<0.05). By curve receiver operator characteristic curve (ROC) analysis, the optimal cut-off levels of 9.41 for NLR and 174 for GRACE score predicted in-hospital death [ROC area under the curve (AUC) 0.771 and 0.787, respectively, P<0.001]. It was concluded that an elevated NLR is a potential predictor of in-hospital mortality in elderly patients with AMI.
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Mortalidade Hospitalar , Linfócitos/patologia , Infarto do Miocárdio/sangue , Infarto do Miocárdio/mortalidade , Neutrófilos/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Feminino , Humanos , Inflamação/sangue , Contagem de Linfócitos , Masculino , Infarto do Miocárdio/imunologia , Prognóstico , Curva ROC , Análise de SobrevidaRESUMO
The long noncoding RNA, homeobox transcript antisense RNA (Hotair), has been demonstrated to have an important role in regulating various biological processes in various cancers, including hepatocellular carcinoma (HCC). However, the importance of Hotair in HCC proliferation and cell cycle progression remains to be elucidated. In the present study, knockdown of HOTAIR expression by RNA interference inhibited cell proliferation and induced G0/G1 cell cycle arrest in Huh7 hepatocellular carcinoma cells. In addition, the expression levels of CCND1 mRNA and its cyclin D1 protein product were reduced in Huh7 cells following knockdown of HOTAIR. Knockdown of HOTAIR reduced the expression of phosphorylated signal transducer and activator of transcription 3 (STAT3) and HOTAIR knockdown combined with STAT3 inhibition led to an additional decrease in cyclin D1 expression. The present study suggested that Hotair may have a critical role in the proliferation of HCC by regulating cell cycle, STAT3 activity and cyclin D1 expression. Therefore, Hotair may be a novel potential therapeutic target for HCC treatment.
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Carcinoma Hepatocelular/genética , Ciclina D1/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , RNA Longo não Codificante/genética , Carcinoma Hepatocelular/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Hepáticas/metabolismo , Interferência de RNA , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismoRESUMO
Divergence in chemosensory traits has been posited as an important component of chemosensory speciation in insects. In particular, chemosensory genes expressed in the peripheral sensory neurons are likely to influence insect behaviors such as preference for food, oviposition sites, and mates. Despite their key role in insect behavior and potentially speciation, the underlying genetic basis for divergence in chemosensory traits remains largely unexplored. One way to ascertain the role of chemosensory genes in speciation is to make comparisons of these genes across closely related species to detect the genetic signatures of divergence. Here, we used high throughput transcriptome analysis to compare chemosensory genes of the sister leaf beetles species Pyrrhalta maculicollis and P. aenescens, whose sexual isolation and host plant preference are mediated by divergent chemical signals. Although there was low overall divergence between transcriptome profiles, there were a number of genes that were differentially expressed between the species. Furthermore, we also detected two chemosensory genes under positive selection, one of which that was also differentially expressed between the species, suggesting a possible role for these genes in chemical-based premating reproductive isolation and host use. Combined with the available chemical and ecological work in this system, further studies of the divergent chemosensory genes presented here will provide insight into the process of chemosensory speciation among Pyrrhalta beetles.
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Quimiotaxia , Besouros/genética , Proteínas de Insetos/genética , Transcriptoma , Animais , Feminino , Proteínas de Insetos/metabolismo , Masculino , Filogenia , Seleção GenéticaRESUMO
Host shifts and subsequent adaption to novel host plants are important drivers of speciation among phytophagous insects. However, there is considerably less evidence for host plant-mediated speciation in the absence of a host shift. Here, we investigated divergence of two sympatric sister elm leaf beetles, Pyrrhalta maculicollis and P. aenescens, which feed on different age classes of the elm Ulmus pumila L. (seedling versus adult trees). Using a field survey coupled with preference and performance trials, we show that these beetle species are highly divergent in both feeding and oviposition preference and specialize on either seedling or adult stages of their host plant. An experiment using artificial leaf discs painted with leaf surface wax extracts showed that host plant chemistry is a critical element that shapes preference. Specialization appears to be driven by adaptive divergence as there was also evidence of divergent selection; beetles had significantly higher survival and fecundity when reared on their natal host plant age class. Together, the results identify the first probable example of divergence induced by host plant age, thus extending how phytophagous insects might diversify in the absence of host shifts.
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Adaptação Fisiológica , Besouros/fisiologia , Comportamento Alimentar , Oviposição , Animais , Besouros/crescimento & desenvolvimento , Feminino , Masculino , Folhas de Planta/química , Plântula , Especificidade da Espécie , Simpatria , Árvores , UlmusRESUMO
Chemical signals in insects have been documented to play an important role in mate recognition, and divergence in chemical signals can often cause sexual isolation between closely related species or populations within species. We investigated the role of cuticular hydrocarbons (CHCs), short distance chemical signals, in male mate recognition between the two sympatric elm leaf beetles, Pyrrhalta maculicollis and Pyrrhaltaaenescens. Mating experiments demonstrated that strong sexual isolation between the two species was driven by CHCs divergence. Males preferred to mate with conspecific females with intact conspecific CHCs or conspecific CHCs reapplied after removal. Males also preferred heterospecific females that were treated with conspecific CHCs. Chemical analysis showed that the CHC profiles differ significantly between species. In P. maculicollis dimethyl-branched alkanes between C29 and C35 account for the majority of the saturated alkanes while the CHC profile of P. aenescens mostly consisted of monomethyl-branched alkanes between C22 and C29. Additionally, some compounds, such as 12,18-diMeC32, 12,18-diMeC34, are unique to P. maculicollis.
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Besouros/fisiologia , Hidrocarbonetos/metabolismo , Preferência de Acasalamento Animal/fisiologia , Isolamento Reprodutivo , Atrativos Sexuais/fisiologia , Animais , Feminino , Masculino , Especificidade da EspécieRESUMO
Host plant shifting of phytophagous insects can lead to the formation of host associated differentiation and ultimately speciation. In some cases, host plant specificity alone acts as a nearly complete pre-mating isolating barrier among insect populations. We here test whether effective pre-mating isolation and host-independent behavioral isolation have evolved under the condition of extreme host specilization using two sympatric flea beetles with incomplete post-mating isolation under laboratory conditions. Phylogenetic analysis and coalescent simulation results showed that there is a limited interspecific gene flow, indicating effctive isolation between these species. Three types of mating tests in the absence of host plant cues showed that strong host-independent behavioral isolation has evolved between them. We conclude that almost perfect assortative mating between these two extreme host specialists results from a combination of reduced encounter rates due to differential host preference and strong sexual isolation.
Assuntos
Besouros/fisiologia , Especiação Genética , Filogenia , Plantas/parasitologia , Comportamento Sexual Animal/fisiologia , Animais , Evolução Biológica , China , Besouros/classificação , Besouros/genética , DNA Mitocondrial/química , DNA Espaçador Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Variação Genética , Geografia , Haplótipos , Especificidade de Hospedeiro , Proteínas de Insetos/classificação , Proteínas de Insetos/genética , Masculino , Dados de Sequência Molecular , Fator 1 de Elongação de Peptídeos/genética , Dinâmica Populacional , Análise de Sequência de DNA , Especificidade da EspécieRESUMO
Fibrinogen-like protein 2 (fgl2) is highly expressed in microvascular endothelial cells in diseases associated with microcirculatory disturbances and plays a crucial role in microthrombosis. Previous studies have demonstrated that the Ser89 residue is a critical site for mouse fgl2 prothrombinase activity. The aim of this study was to investigate the prothrombinase inhibitory ability of antibodies against an hfgl2-derived peptide. The peptide was termed NPG-12 because it is located at the N-terminus of membrane-bound hfgl2, contains 12 amino acid residues (corresponding to residues 76 to 87), and is rich in Glu. This peptide was selected as an antigenic determinant to produce antibodies in immunized rabbits using the DNAStar and HomoloGene software program. Abundant hfgl2 expression was induced in human umbilical vein endothelial cells through treatment with TNF-α. The generated anti-NPG-12 antibodies specifically recognize fgl2, as determined by ELISA, Western Blot and immunostaining. Moreover, one-stage clotting and thrombin generation tests provide evidence that the antibodies can reduce the hfgl2 prothrombinase activity without affecting the platelet-poor plasma prothrombin time (PT) or the activated partial thromboplastin time (APTT). In addition, the antibodies exerted undetectable influence on the proliferation or activation of bulk T cell populations. In conclusion, the selected peptide sequence NPG-12 may be a critical domain for hfgl2 prothrombinase activity, and the development of inhibitors against this sequence may be promising for research or management of hfgl2-associated microcirculatory disturbances.
Assuntos
Anticorpos/farmacologia , Fibrinogênio/antagonistas & inibidores , Fibrinogênio/imunologia , Ácido Glutâmico/imunologia , Peptídeos/imunologia , Serina/metabolismo , Tromboplastina/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Especificidade de Anticorpos/efeitos dos fármacos , Especificidade de Anticorpos/imunologia , Polaridade Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Fibrinogênio/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Ativação Linfocitária/efeitos dos fármacos , Masculino , Modelos Moleculares , Dados de Sequência Molecular , Tempo de Tromboplastina Parcial , Peptídeos/química , Tempo de Protrombina , Coelhos , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Tromboplastina/metabolismoRESUMO
BACKGROUND: Fig pollinating wasps form obligate symbioses with their fig hosts. This mutualism arose approximately 75 million years ago. Unlike many other intimate symbioses, which involve vertical transmission of symbionts to host offspring, female fig wasps fly great distances to transfer horizontally between hosts. In contrast, male wasps are wingless and cannot disperse. Symbionts that keep intimate contact with their hosts often show genome reduction, but it is not clear if the wide dispersal of female fig wasps will counteract this general tendency. We sequenced the genome of the fig wasp Ceratosolen solmsi to address this question. RESULTS: The genome size of the fig wasp C. solmsi is typical of insects, but has undergone dramatic reductions of gene families involved in environmental sensing and detoxification. The streamlined chemosensory ability reflects the overwhelming importance of females finding trees of their only host species, Ficus hispida, during their fleeting adult lives. Despite long-distance dispersal, little need exists for detoxification or environmental protection because fig wasps spend nearly all of their lives inside a largely benign host. Analyses of transcriptomes in females and males at four key life stages reveal that the extreme anatomical sexual dimorphism of fig wasps may result from a strong bias in sex-differential gene expression. CONCLUSIONS: Our comparison of the C. solmsi genome with other insects provides new insights into the evolution of obligate mutualism. The draft genome of the fig wasp, and transcriptomic comparisons between both sexes at four different life stages, provide insights into the molecular basis for the extreme anatomical sexual dimorphism of this species.