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1.
Insect Mol Biol ; 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38949741

ABSTRACT

Transcriptomic data have been used to study sex chromosome dosage compensation (SCDC) in approximately 10 Lepidoptera ZW species, yielding a consensus compensation pattern of Z ≈ ZZ < AA . $$ \approx \mathrm{ZZ}<\mathrm{AA}. $$ It remains unclear whether this compensation pattern holds when examining more Lepidoptera ZW species and/or using proteomic data to analyse SCDC. Here we combined transcriptomic and proteomic data as well as transcriptional level of six individual Z genes to reveal the SCDC pattern in Helicoverpa armigera, a polyphagous lepidopteran pest of economic importance. Transcriptomic analysis showed that the Z chromosome expression of H. armigera was balanced between male and female but substantially reduced relative to autosome expression, exhibiting an SCDC pattern of Z ≈ ZZ < AA $$ \approx \mathrm{ZZ}<\mathrm{AA} $$ . When using H. amigera midgut proteomic data, the SCDC pattern of this species changed from Z ≈ ZZ < AA $$ \approx \mathrm{ZZ}<\mathrm{AA} $$ at transcriptomic level to Z = ZZ = AA at the proteomic level. RT-qPCR analysis of transcript abundance of six Z genes found that compensation for each Z gene could vary from no compensation to overcompensation, depending on the individual genes and tissues tested. These results demonstrate for the first time the existence of a translational compensation mechanism, which is operating in addition to a translational mechanism, such as has been reported in other lepidopteran species. And the transcriptional compensation mechanism functions to accomplish Z chromosome dosage balance between the sexes (M = F on the Z chromosome), whereas the translation compensation mechanism operates to achieve dosage compensation between Z chromosome and autosome (Z = AA).

2.
Insects ; 15(5)2024 May 02.
Article in English | MEDLINE | ID: mdl-38786884

ABSTRACT

Expressions of a wide range of cytoprotective counter-defense genes are mainly regulated by the Keap1-Nrf2-ARE signaling pathway in response to oxidative stress from xenobiotics. Gossypol is the major antiherbivore secondary metabolite of cotton, but how the polyphagous pest Helicoverpa armigera copes with this phytochemical to utilize its favorite host plant cotton remains largely elusive. In this study, we first suppressed the Keap1 gene in newly hatched larvae of cotton bollworm by feeding them the siRNA diet for 4 days. All of the larvae were subsequently fed the artificial diet supplied with gossypol or the control diet for 5 days. We identified that the knockdown of the Keap1 gene significantly decreased larval mortality and significantly increased the percentages of larval survival, reaching the fourth instar, compared with ncsiRNA when exposed to a diet containing gossypol. Three counter-defense genes CYP9A17, CYP4L11 and UGT41B3, which were related to the induction or metabolism of gossypol according to the report before, were all significantly up-regulated after the knockdown of the Keap1 gene. The Antioxidant Response Elements (AREs) were also detected in the promoter regions of the three counter-defense genes above. These data indicate that the suppression of the Keap1 gene activates the Keap1-Nrf2-ARE signaling pathway, up-regulates the expressions of counter-defense genes involved in the resistance of oxidative stress and finally contributes to reducing the susceptibility of gossypol. Our results provide more knowledge about the transcriptional regulation mechanisms of counter-defense genes that enable the cotton bollworm to adapt to the diversity of host plants including cotton.

3.
Pestic Biochem Physiol ; 198: 105744, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38225087

ABSTRACT

Cry2Ab is one of the important alternative Bt proteins that can be used to manage insect pests resistant to Cry1A toxins and to expand the insecticidal spectrum of pyramided Bt crops. Previous studies have showed that vacuolar H+-ATPase subunits A and B (V-ATPase A and B) may be involved in Bt insecticidal activities. The present study investigated the role of V-ATPases subunit E in the toxicity of Cry2Ab in Helicoverpa amigera. RT-PCR analysis revealed that oral exposure of H. amigera larvae to Cry2Ab led to a significant reduction in the expression of H. armigera V-ATPase E (HaV-ATPase E). Ligand blot, homologous and heterologous competition experiments confirmed that HaV-ATPases E physically and specifically bound to activated Cry2Ab toxin. Heterologous expressing of HaV-ATPase E in Sf9 cells made the cell line more susceptible to Cry2Ab, whereas knockdown of the endogenous V-ATPase E in H. zea midgut cells decreased Cry2Ab's cytotoxicity against this cell line. Further in vivo bioassay showed that H. armigera larvae fed a diet overlaid with both Cry2Ab and E. coli-expressed HaV-ATPase E protein suffered significantly higher mortality than those fed Cry2Ab alone. These results support that V-ATPases E is a putative receptor of Cry2Ab and can be used to improve Cry2Ab toxicity and manage Cry2Ab resistance at least in H. armigera.


Subject(s)
Bacillus thuringiensis , Insecticides , Moths , Animals , Helicoverpa armigera , Endotoxins/toxicity , Endotoxins/metabolism , Adenosine Triphosphatases/genetics , Adenosine Triphosphatases/metabolism , Escherichia coli , Bacillus thuringiensis Toxins/metabolism , Moths/genetics , Moths/metabolism , Larva/metabolism , Insecticides/toxicity , Insecticides/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Hemolysin Proteins/genetics , Hemolysin Proteins/toxicity , Hemolysin Proteins/metabolism , Bacillus thuringiensis/metabolism , Insecticide Resistance
4.
Nutrients ; 15(19)2023 Oct 05.
Article in English | MEDLINE | ID: mdl-37836550

ABSTRACT

As an important resource insect, the Cryptotympana atrata is widely distributed in the eastern and central parts of China. The cicada slough is one of the traditional crude drugs in East Asia, and the main component is polysaccharide, which has the functions of anti-convulsion, relieving asthma and improving lipid metabolism. The parasitoid fungus Cordyceps cicadae, which grows inside the cicada nymphs and forms the fruiting bodies on the surface of the host's carcass, is also known as the "cicada flower" in China. The Cordyceps cicadae is another old, traditional Chinese medicine, which has been used as a tonic and medicine to nourish and regulate human immunity for centuries. For the further development and utilization of the golden cicada, this paper summarized the C. atrata from the aspects of their biological characteristics, distribution area, life cycle, history of edible and medicinal use, edible methods and nutritional compositions; emphatically introduced the edible and potential medicinal value of the C. atrata; and specifically expounded the research progress of its application. As one popular insect food, the prospects for the development of C. atrata have also been put forward, especially in artificial breeding technology, food safety risk assessment and medicinal value utilization.


Subject(s)
Cordyceps , Hemiptera , Animals , Humans , Plant Breeding , Hemiptera/metabolism , Hemiptera/microbiology , China
5.
Insects ; 14(9)2023 Aug 31.
Article in English | MEDLINE | ID: mdl-37754704

ABSTRACT

Target pests of genetically engineered crops producing both defensive allelochemicals and Bacillus thuringiensis (Bt) toxins often sequentially or simultaneously uptake allelochemicals, Bt toxins, and/or insecticides. How the three types of toxins interact to kill pests remains underexplored. Here we investigated the interactions of Bt toxin Vip3A, plant allelochemical flavone, and insecticide emamectin benzoate in Spodoptera frugiperda. Simultaneous administration of flavone LC25 + Vip3A LC25, emamectin benzoate LC25 + Vip3A LC25, and flavone LC15 + emamectin benzoate LC15 + Vip3A LC15 but not flavone LC25 + emamectin LC25 yielded a mortality significantly higher than their expected additive mortality (EAM). One-day pre-exposure to one toxin at LC5 followed by six-day exposure to the same toxin at LC5 plus another toxin at LC50 showed that the mortality of flavone LC5 + Vip3A LC50, emamectin benzoate LC5 + Vip3A LC50, and Vip3A LC5 + emamectin benzoate LC50 were significantly higher than their EAM, while that of flavone LC5 + emamectin benzoate LC50 was significantly lower than their EAM. No significant difference existed among the mortalities of Vip3A LC5 + flavone LC50, emamectin benzoate LC5 + flavone LC50, and their EAMs. The results suggest that the interactions of the three toxins are largely synergistic (inductive) or additive, depending on their combinations and doses.

6.
Toxins (Basel) ; 15(6)2023 05 29.
Article in English | MEDLINE | ID: mdl-37368666

ABSTRACT

Flavone is widely found in plants and plays an important role in plant defense against pests. Many pests, such as Helicoverpa armigera, use flavone as a cue to upregulate counter-defense genes for detoxification of flavone. Yet the spectrum of the flavone-inducible genes and their linked cis-regulatory elements remains unclear. In this study, 48 differentially expressed genes (DEGs) were found by RNA-seq. These DEGs were mainly concentrated in the retinol metabolism and drug metabolism-cytochrome P450 pathways. Further in silico analysis of the promoter regions of 24 upregulated genes predicted two motifs through MEME and five previously characterized cis-elements including CRE, TRE, EcRE, XRE-AhR and ARE. Functional analysis of the two predicted motifs and two different versions of ARE (named ARE1 and ARE2) in the promoter region of the flavone-inducible carboxylesterase gene CCE001j verified that the two motifs and ARE2 are not responsible for flavone induction of H. armigera counter-defense genes, whereas ARE1 is a new xenobiotic response element to flavone (XRE-Fla) and plays a decisive role in flavone induction of CCE001j. This study is of great significance for further understanding the antagonistic interaction between plants and herbivorous insects.


Subject(s)
Flavones , Moths , Animals , Moths/genetics , Moths/metabolism , Cytochrome P-450 Enzyme System/genetics , Cytochrome P-450 Enzyme System/metabolism , Flavones/metabolism , Larva
7.
J Agric Food Chem ; 2023 Apr 10.
Article in English | MEDLINE | ID: mdl-37036055

ABSTRACT

Insect resistance to Bacillus thuringiensis (Bt) toxins has led to an urgent need to explore the insecticidal mechanisms of Bt. Previous studies indicated that Helicoverpa armigera ATP synthase subunit α (HaATPs-α) is involved in Cry1Ac resistance. In this study, a real-time quantitative polymerase chain reaction (RT-PCR) confirmed that HaATPs-α expression was significantly reduced in the Cry1Ac-resistant strain (BtR). Cry1Ac feeding induced the downregulated expression of HaATPs-α in the susceptible strain, but not in the BtR strain. Furthermore, the interaction between HaATPs-α and Cry1Ac was verified by ligand blotting and homologous competition experiments. The in vitro gain and loss of function analyses showed HaATPs-α involved in Cry1Ac toxicity by expressing endogenous HaATPs-α and HaATPs-α double-stranded RNAs in Sf9 and midgut cells, respectively. Importantly, purified HaATPs-α synergized Cry1Ac toxicity to H. armigera larvae. These findings provide the first evidence that HaATPs-α is a potential receptor of Cry1Ac, it shows downregulated participation in Cry1Ac resistance, and it exhibits higher enhancement of Cry1Ac toxicity to H. armigera larvae.

8.
Int J Biol Macromol ; 226: 840-852, 2023 Jan 31.
Article in English | MEDLINE | ID: mdl-36481335

ABSTRACT

Spodoptera frugiperda (Lepidoptera: Noctuidae) is a globally distributed lepidopteran crop pest that has developed resistance to most insecticides. The G-quadruplex (G4) is a secondary structure in the genome enriched in the promoters for regulating gene expression. However, little is known about G4 in S. frugiperda, especially whether G4 is involved in insecticide resistance and pest control. In this study, 387,875 G4 motifs in the whole genome of S. frugiperda were identified by bioinformatics prediction. We found that 66.90 % of theseG4 structures were located in genic regions and highly enriched in the upstream regions of start codons. Functional and pathway analyses showed that the genes with G4 enriched in promoter regions participate in several metabolic processes. Further analyses showed that G4 structures occurred more frequently in the promoters of P450 and CarE gene families. It was also investigated that G4 ligand N-methyl mesoporphyrin IX (NMM) decreased P450 protein activity in larval midgut tissue. Cytotoxicity and bioassay results revealed that NMM and pesticides had synergistic effects on toxicity. In conclusion, our findings suggest that G4 motif could be a new potential target for pest control.


Subject(s)
G-Quadruplexes , Insecticides , Animals , Spodoptera/genetics , Insecticides/pharmacology , Larva
9.
Insects ; 13(9)2022 Sep 02.
Article in English | MEDLINE | ID: mdl-36135504

ABSTRACT

During the messenger RNA (mRNA) maturation process, RNA polyadenylation is a key step, and is coupled to the termination of transcription. Various cis-acting elements near the cleavage site and their binding factors would affect the process of polyadenylation, and AAUAAA, a highly conserved hexamer, was the most important polyadenylation signal (PAS). PAS usage is one of the critical modification determinants targeted at mRNA post-transcription. The full-length transcriptome has recently generated a massive amount of sequencing data, revealing poly(A) variation and alternative polyadenylation (APA) in Spodoptera frugiperda. We identified 50,616 polyadenylation signals in Spodoptera frugiperda via analysis of full-length transcriptome combined with expression Sequence Tags Technology (EST). The polyadenylation signal usage in Spodoptera frugiperda is conserved, and it is similar to that of flies and other animals. AAUAAA and AUUAAA are the most highly conserved polyadenylation signals of all polyadenylation signals we identified. Additionally, we found the U/GU-rich downstream sequence element (DSE) in the cleavage site. These results demonstrate that APA in Spodoptera frugiperda plays a significant role in root growth and development. This is the first polyadenylation signal usage analysis in agricultural pests, which can deepen our understanding of Spodoptera frugiperda and provide a theoretical basis for pest control.

10.
Article in English | MEDLINE | ID: mdl-35886662

ABSTRACT

Human muscle tissue undergoes dynamic changes in gene expression during exercise, and the dynamics of these genes are correlated with muscle adaptation to exercise. A database of gene expression changes in human muscle before and after exercise was established for data mining. A web-based searchable database, Exe-muscle, was developed using microarray sequencing data, which can help users to retrieve gene expression at different times. Search results provide a complete description of target genes or genes with specific expression patterns. We can explore the molecular mechanisms behind exercise science by studying the changes in muscle gene expression over time before and after exercise. Based on the high-throughput microarray data before and after human exercise, a human pre- and post-exercise database was created using web-based database technology, which researchers can use or share their gene expression data. The Exe-muscle database is accessible online.


Subject(s)
Physical Conditioning, Animal , Animals , Gene Expression , Humans , Muscle, Skeletal/physiology , Physical Conditioning, Animal/physiology
11.
Insect Sci ; 29(6): 1629-1642, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35226400

ABSTRACT

Insects utilize xenobiotic compounds to up- and downregulate cytochrome P450 monooxygenases (P450s) involved in detoxification of toxic xenobiotics including phytochemicals and pesticides. G-quadruplexes (G4)-forming DNA motifs are enriched in the promoter regions of transcription factors and function as cis-acting elements to regulate these genes. Whether and how P450s gain and keep G4 DNA motifs to regulate their expression still remain unexplored. Here, we show that CYP321A1, a xenobiotic-metabolizing P450 from Helicoverpa zea, a polyphagous insect of economic importance, has acquired and preserved a G4 DNA motif by selectively retaining a transposon known as HzIS1-3 that carries this G4 DNA motif in its promoter region. The HzIS1-3 G4 DNA motif acts as a silencer to suppress the constitutive and induced expression of CYP321A1 by plant allelochemicals flavone and xanthotoxin through folding into an intramolecular parallel or hybrid-1 conformation in the absence or presence of K+ . The G4 ligand N-methylmesoporphyrin IX (NMM) strengthens the silencing effect of HzIS1-3 G4 DNA motif by switching its structure from hybrid-1 to hybrid-2. The enrichment of transposons in P450s and other environment-adaptation genes implies that selective retention of G4 DNA motif-carrying transposons may be the main evolutionary route for these genes to obtain G4 DNA motifs.


Subject(s)
G-Quadruplexes , Moths , Animals , Xenobiotics , Moths/genetics , Cytochrome P-450 Enzyme System/genetics , Pheromones
12.
Animals (Basel) ; 12(2)2022 Jan 13.
Article in English | MEDLINE | ID: mdl-35049816

ABSTRACT

RNA polyadenylation is an important step in the messenger RNA (mRNA) maturation process, and the first step is recognizing the polyadenylation signal (PAS). The PAS type and distribution is a key determinant of post-transcriptional mRNA modification and gene expression. However, little is known about PAS usage and alternative polyadenylation (APA) regulation in livestock species. Recently, sequencing technology has enabled the generation of a large amount of sequencing data revealing variation in poly(A) signals and APA regulation in Sus scrofa. We identified 62,491 polyadenylation signals in Sus scrofa using expressed sequence tag (EST) sequences combined with RNA-seq analysis. The composition and usage frequency of polyadenylation signal in Sus scrofa is similar with that of human and mouse. The most highly conserved polyadenylation signals are AAUAAA and AUUAAA, used for over 63.35% of genes. In addition, we also analyzed the U/GU-rich downstream sequence (DSE) element, located downstream of the cleavage site. Our results indicate that APA regulation was widely occurred in Sus scrofa, as in other organisms. Our result was useful for the accurate annotation of RNA 3' ends in Sus scrofa and the analysis of polyadenylation signal usage in Sus scrofa would give the new insights into the mechanisms of transcriptional regulation.

13.
Insect Sci ; 29(3): 631-644, 2022 Jun.
Article in English | MEDLINE | ID: mdl-34232550

ABSTRACT

MicroRNAs (miRNAs) are regulatory RNA molecules that bind to target messenger RNAs (mRNAs) and affect the stability or translational efficiency of the bound mRNAs. Single or dual-luciferase reporter systems have been successfully used to identify miRNA target genes in mammalian cells. These reporter systems, however, are not sensitive enough to verify miRNA-target gene relationships in insect cell lines because the promoters of the target luciferase (usually Renilla) used in these reporter systems are too weak to drive sufficient expression of the target luciferase in insect cells. In this study, we replaced the SV40 promoter in the psiCHECK-2 reporter vector, which is widely used with mammalian cell lines, with the HSV-TK or AC5.1 promoter to yield two new dual-luciferase reporter vectors, designated psiCHECK-2-TK and psiCHECK-2-AC5.1, respectively. Only psiCHECK-2 and psiCHECK-2-AC5.1 had suitable target (Renilla)/reference (firefly) luciferase activity ratios in mammalian (HeLa and HEK293) and insect (Sf9, S2, Helicoverpa zea fat body and ovary) cell lines, while psiCHECK-2-TK had suitable Renilla/firefly luciferase activity ratios regardless of the cell line. Moreover, psiCHECK-2-TK successfully detected the interaction between Helicoverpa armigera miRNA9a and its target, the 3'-untranslated region of heat shock protein 90, in both mammalian and H. zea cell lines, but psiCHECK-2 failed to do so in H. zea cell lines. Furthermore, psiCHECK-2-TK with the target sequence, HzMasc (H. zea Masculinizer), accurately differentiated between H. zea cell lines with or without the negative regulation factor (miRNA or piRNA) of HzMasc. These data demonstrate that psiCHECK-2-TK can be used to functionally characterize small RNA target genes in both mammalian and insect cells.


Subject(s)
Genes, Reporter , MicroRNAs , Animals , HEK293 Cells , HeLa Cells , Humans , Insecta/genetics , Insecta/metabolism , Luciferases/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Messenger/metabolism , Sf9 Cells
14.
Int J Mol Sci ; 22(16)2021 Aug 11.
Article in English | MEDLINE | ID: mdl-34445352

ABSTRACT

The Masculinizer (Masc) gene has been known to control sex development and dosage compensation in lepidopterans. However, it remains unclear whether its ortholog exists and plays the same roles in distantly related lepidopterans such as Helicoverpa armigera. To address this question, we cloned Masc from H. armigera (HaMasc), which contains all essential functional domains of BmMasc, albeit with less than 30% amino acid sequence identity with BmMasc. Genomic PCR and qPCR analyses showed that HaMasc is a Z chromosome-linked gene since its genomic content in males (ZZ) was two times greater than that in females (ZW). RT-PCR and RT-qPCR analyses revealed that HaMasc expression was sex- and stage-biased, with significantly more transcripts in males and eggs than in females and other stages. Transfection of a mixture of three siRNAs of HaMasc into a male embryonic cell line of H. armigera led to the appearance of female-specific mRNA splicing isoforms of H. armigeradoublesex (Hadsx), a downstream target gene of HaMasc in the H. armigera sex determination pathway. The knockdown of HaMasc, starting from the third instar larvae resulted in a shift of Hadsx splicing from male to female isoforms, smaller male pupa and testes, fewer but larger/longer spermatocytes and sperm bundles, delayed pupation and internal fusion of the testes and follicles. These data demonstrate that HaMasc functions as a masculinizing gene in the H. armigera sex-determination cascade.


Subject(s)
Insect Proteins/physiology , Moths/genetics , Sex Determination Processes/genetics , Amino Acid Sequence , Animals , Cloning, Molecular , Dosage Compensation, Genetic , Female , Insect Proteins/genetics , Larva , Male , Moths/classification , Phylogeny , RNA Isoforms , Sequence Analysis, DNA , Sex Chromosomes
15.
Insects ; 12(8)2021 Aug 19.
Article in English | MEDLINE | ID: mdl-34442315

ABSTRACT

The high fecundity of the most destructive pest Helicoverpa armigera and its great resistance risk to insecticides and Bt crops make the reproductive-destruction-based control of this pest extremely appealing. To find suitable targets for disruption of its reproduction, we observed the testis and ovary development of H. armigera and conducted deep sequencing of the ovary and testis small RNAs of H. armigera and quantitative RT-PCR (RT-qPCR) validation to identify reproduction-related micro RNAs (miRNAs). A total of 7,592,150 and 8,815,237 clean reads were obtained from the testis and ovary tissue, respectively. After further analysis, we obtained 173 novel and 74 known miRNAs from the two libraries. Among the 74 known miRNAs, 60 miRNAs existed in the ovary and 72 existed in the testis. Further RT-qPCR validation of 5 miRNAs from the ovary and 6 miRNAs from the testis confirmed 8 of them were indeed ovary- (miR-989a, miR-263-5p, miR-34) or testis-biased (miR-2763, miR-998, miR-2c, miR-2765, miR-252a-5p). The 8 ovary- or testis-biased miRNAs had a total of 30,172 putative non-redundant target transcripts, as predicted by miRanda and RNAhybrid. Many of these target transcripts are assigned to reproduction-related GO terms (e.g., oocyte maturation, vitellogenesis, spermatogenesis) and are members of multiple reproduction-related KEGG pathways, such as the JAK-STAT signaling pathway, oocyte meiosis, the insulin signaling pathway, and insect hormone biosynthesis. These results suggest that the 8 gonad-biased miRNAs play important roles in reproduction and may be used as the targets for the development of reproductive-destruction-based control of H. armigera and, possibly, other lepidopteran pests.

16.
Curr Opin Insect Sci ; 43: 108-116, 2021 02.
Article in English | MEDLINE | ID: mdl-33385580

ABSTRACT

Insect herbivores use phytochemicals as signals to induce expression of their phytochemical-detoxifying cytochrome P450 monooxygenases (P450s). The regulatory cascades that transduce phytochemical signals to enhanced expression of P450s are the focus of this review. At least seven signaling pathways, including RTK/MAPK, GPCR/CREB, GPCR/NFκB, ROS/CncC/Keap1, AhR/ARNT, cytosol NR, and nucleus-located NR, may be involved in phytochemical induction of P450s. Constitutive overexpression, overphosphorylation, and/or activation of one or more effectors in the corresponding pathway are common causes of P450 overexpression that lead to phytochemical or insecticide resistance. Future research should pay more attentions to the starting point of each pathway, the number of pathways and their cross talk for a given phytochemical, and the pathways for downregulation of P450s.


Subject(s)
Cytochrome P-450 Enzyme System , Insecta/enzymology , Animals , Herbivory , Inactivation, Metabolic , Phytochemicals , Signal Transduction
17.
Insect Sci ; 28(6): 1756-1765, 2021 Dec.
Article in English | MEDLINE | ID: mdl-33377308

ABSTRACT

Genetically engineered crops simultaneously produce defensive allelochemicals and Bacillus thuringiensis (Bt) toxin proteins to kill some of the world's most devastating insect pests. How the two types of toxins, when ingested sequentially or simultaneously, interact at both lethal and sublethal doses in these pests remains underexplored. Here, we examined the toxicological interactions between the Bt toxin Cry1Ac and the flavonoid allelochemical flavone in Helicoverpa armigera. Simultaneous exposure of H. armigera neonates to lethal doses (LC25 ) of Cry1Ac and flavone caused a mortality significantly higher than that of either toxin alone and their expected additive mortality. Preexposure for 24 h to a sublethal dose (LC10 ) of Cry1Ac followed by 6-d simultaneous exposure to the same dose of Cry1Ac plus a lethal dose (1.6 mg/g diets, LC50 ) of flavone resulted in a mortality significantly higher than that of the LC50 dose of flavone alone and the expected additive mortality of the LC50 dose of flavone plus the LC10 dose of Cry1Ac. One-day preexposure to the sublethal dose (LC10 ) of flavone followed by 6-d simultaneous exposure to the LC50 dose (6 ng/cm2 ) of Cry1Ac plus the LC10 dose of flavone yielded a mortality significantly higher than that of the LC50 dose of Cry1Ac but similar to the expected additive mortality of the LC50 dose of Cry1Ac plus the LC10 dose of flavone. The results suggest that Cry1Ac induces and synergizes the toxicity of flavone against H. armigera larvae.


Subject(s)
Bacillus thuringiensis Toxins/toxicity , Flavones , Insect Control , Moths , Pheromones , Animals , Flavones/toxicity , Larva , Pheromones/toxicity
18.
Article in English | MEDLINE | ID: mdl-32974317

ABSTRACT

BACKGROUND: A second dorsal metacarpal artery cutaneous branches flap is often used to repair skin defects in the hand. The location of the cutaneous branch of that artery is very critical for the removal of the flap. In this study, we quantitatively analyzed the origin of the cutaneous branches of the second dorsal metacarpalartery and the distribution characteristics of the radial and ulnar side to provide an anatomical basis for designing a flap. METHODS: Sixteen upper limb specimens were perfused with latex. Four specimens were infused with ethyl acetate plus plastic, and four specimens were perfused with red latex to create pellucid specimens. The origin, travel paths, and distribution of the cutaneous branches of the second dorsal metacarpal artery were anatomically observed, and we measured the length of the cutaneous branch from the midpoint of the second web space edge. We also measured the diameters and pedicle lengths of the radial and ulnar distributions of cutaneous branches of the second dorsal metacarpal artery. RESULTS: The cutaneous branches of the second dorsal metacarpal artery were mainly clustered at three positions, the second cluster point was at 43.9%, the fourth cluster point was at 61.2%, and the fifth cluster point was at 72.1%. The first cluster point was at 30.8% and the sixth cluster point was at 85.6%. The diameter and pedicle length of the sixth cluster point were the largest. There was no significant difference in the distribution of the diameters and pedicle lengths of the cutaneous branch between the radial and ulnar side. The second dorsal metacarpal artery sent out 1-2 cutaneous branches before the tendon joint, and formed a blood vessel anastomosis with other cutaneous branches located further from the tendon joint. The dorsal branch of the radial nerve in the hand extended a nerve branch at the wrist joint and traveled between the cutaneous branches of the second dorsal metacarpal artery to dominate the corresponding skin. CONCLUSION: Three clusters in the distal second dorsal metacarpal artery were selected to be the flap pedicle containing a cutaneous nerve for use in repairing a skin defect in the hand and fingers.

19.
Front Genet ; 11: 649, 2020.
Article in English | MEDLINE | ID: mdl-32636875

ABSTRACT

Helicoverpa armigera is a globally-important crop pest with a WZ (female)/ZZ (male) sex chromosome system. The absence of discernible sexual dimorphism in its egg and larval stages makes it impossible to address any sex-related theoretical and applied questions before pupation unless a W-specific sequence marker is available for sex diagnosis. To this end, we used one pair of morphologically pre-sexed pupae to PCR-screen 17 non-transposon transcripts selected from 4855 W-linked candidate reads identified by mapping a publicly available egg transcriptome of both sexes to the male genome of this species and detected the read SRR1015458.67499 only in the female pupa. Subsequent PCR screenings of this read and the previously reported female-specific RAPD (random amplified polymorphic DNA) marker AF18 with ten more pairs of pre-sexed pupae and different annealing positions and/or temperatures as well as its co-occurrence with the female-specific transcript splicing isoforms of doublesex gene of H. armigera (Hadsx) and amplification and sequencing of their 5' unknown flanking sequences in three additional pairs of pre-sexed pupae verified that SRR1015458.67499 is a single copy protein-coding gene unique to W chromosome (named GUW1) while AF18 is a multicopy MITE transposon located on various chromosomes. Test application of GUW1 as a marker to sex 30 neonates of H. armigera yielded a female/male ratio of 1.14: 1.00. Both GUW1 and Hadsx splicing isoforms assays revealed that the H. armigera embryo cell line QB-Ha-E-1 is a male cell line. Taken together, GUW1 is not only a reliable DNA marker for sexing all stages of H. armigera and its cell lines, but also represents the first W-specific protein-coding gene in lepidopterans.

20.
World Neurosurg ; 113: 225-231, 2018 May.
Article in English | MEDLINE | ID: mdl-29499425

ABSTRACT

BACKGROUND: The concern of adjacent segment disease (ASD) has led to the development of motion-preserving technologies, such as cervical disc arthroplasty (CDA). However, there is still controversy whether CDA is superior to anterior cervical decompression and fusion (ACDF) as to the incidence of ASD. The purpose of this study is to evaluate the rate of ASD between CDA and ACDF. METHODS: Systematic searches of all relevant studies through November 2017 were identified from the Cochrane Library, PubMed, Embase, and CNKI. Randomized controlled trials comparing the clinical effectiveness of CDA and ACDF for cervical degenerative disc disease (DDD) were included. Two independent reviewers searched and assessed all literature according to the standard of Cochrane systematic review. Data extraction and quality assessment were conducted, and RevMan 5.2 was used for data analysis. The random effects model was used if there was heterogeneity between studies; otherwise, the fixed effects model was used. RESULTS: Twenty-one studies were included in our meta-analysis. The pooled data revealed that the CDA group had significantly lower adjacent segment diseases than the ACDF group did. Furthermore, there were fewer adjacent segment reoperations in the CDA group compared with the ACDF group. CONCLUSIONS: In this meta-analysis, we conclude that CDA was better than the ACDF in terms of ASD and adjacent segment reoperations. This conclusion suggests that CDA is a superior alternative invention for the treatment of cervical DDD to preserve cervical range of motion and reduce the risk of ASD; however, this requires further validation and investigation in larger sample-size prospective and randomized studies with long-term follow-up.


Subject(s)
Arthroplasty/methods , Cervical Vertebrae/surgery , Decompression, Surgical/methods , Intervertebral Disc Degeneration/surgery , Randomized Controlled Trials as Topic/methods , Spinal Fusion/methods , Arthroplasty/standards , Cervical Vertebrae/pathology , Decompression, Surgical/standards , Humans , Intervertebral Disc Degeneration/diagnosis , Randomized Controlled Trials as Topic/standards , Range of Motion, Articular/physiology , Spinal Fusion/standards
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