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1.
Pest Manag Sci ; 80(7): 3194-3206, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38348909

RESUMO

BACKGROUND: Oogenesis is a complex pathway necessary for proper female reproduction in insects. Ovary-serine protease (Osp) is a homologous gene of serine protease Nudel (SpNudel) and plays an essential role in the oogenesis and ovary development of Drosophila melanogaster. However, the function of Osp is not determined in Plutella xylostella, a highly destructive pest of cruciferous crops. RESULTS: The PxOsp gene comprises a 5883-bp open-reading frame that encodes a protein consisting of 1994 amino acids, which contain four conserved domains. PxOsp exhibited a high relative expression in adult females with a specific expression in the ovary. Through the utilization of CRISPR/Cas9 technology, homozygous mutants of PxOsp were generated. These homozygous mutant females produced fewer eggs (average of 56 eggs/female) than wild-type (WT) females (average of 97 eggs/female) when crossed with WT males, and these eggs failed to hatch. Conversely, mutant males produced normal progeny when crossed with WT females. The ovarioles in homozygous mutant females were significantly shorter (5.02 mm in length) and contained fewer eggs (average of 3 eggs/ovariole) than WT ovarioles (8.09 mm in length with an average of 8 eggs/ovariole). Moreover, eggs laid by homozygous mutant females were fragile, with irregular shapes, and were unable to maintain structural integrity due to eggshell ruptures. However, no significant differences were observed between WT and mutant individuals regarding developmental duration, pupal weight, and mating behavior. CONCLUSION: Our study suggesteds that PxOsp plays a vital role in female reproduction, particularly in ovary and egg development. Disrupting PxOsp results in recessive female sterility while leaving the male reproductive capability unaffected. This report represents the first study of a haplosufficient gene responsible for female fertility in lepidopteran insects. Additionally, these findings emphasize PxOsp as a potential target for genetically-based pest management of P. xylostella. © 2024 Society of Chemical Industry.


Assuntos
Sistemas CRISPR-Cas , Fertilidade , Mariposas , Ovário , Serina Proteases , Animais , Feminino , Mariposas/genética , Mariposas/crescimento & desenvolvimento , Ovário/crescimento & desenvolvimento , Fertilidade/genética , Serina Proteases/genética , Serina Proteases/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Masculino
2.
Phys Chem Chem Phys ; 26(5): 4572-4578, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38247378

RESUMO

Using a three-dimensional classical ensemble model, nonsequential double ionization (NSDI) of Ar atoms by counter-rotating two-color elliptical polarization (TCEP) fields is investigated. The major axes of the two elliptical fields are aligned in different directions. The relative alignment of the two elliptical fields strongly affects the waveform of the combined electric field and the ultrafast dynamics of NSDI in TCEP fields. Numerical results show that the correlated electron momentum distributions in the x direction evolve from a V-shaped structure near the axis to a distribution concentrated on the diagonal with the angle between the two elliptical major axes increasing. The asymmetry of the energy sharing between the two electrons during recollision results in the V-shaped structure in the correlated momentum spectrum. Back analysis indicates that the recollision times of a part of the trajectories move from the peak to the valley of the combined electric field with the angle between the two elliptical major axes increasing. Therefore, for the case of a larger angle between the two elliptical major axes, the electrons experience a longer time to escape away from the vicinity of the parent ion and thus the stronger Coulomb effect from the parent ion makes the momentum difference between two electrons small, which results in a distribution concentrated on the diagonal. This provides an effective avenue to control the electron ultrafast dynamics in NSDI.

3.
Pest Manag Sci ; 80(4): 2109-2119, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38133081

RESUMO

BACKGROUND: Dicer is an endonuclease that belongs to the RNase III family and can specifically recognize and cleave double-stranded RNA (dsRNA). In most insects, there are two Dicer genes, Dicer-1 (Dcr-1) and Dicer-2 (Dcr-2), which are involved in the micro-RNA and small-interfering RNA pathways in many species, respectively. The function of Dicer in Plutella xylostella remains unknown. RESULTS: The full-length open reading frames of P. xylostella Dicer-1 (PxDcr-1) and Dicer-2 (PxDcr-2) were cloned and sequenced. Dcr-1 and Dcr-2 proteins shared similar structural domains with the Dicer-Partner Binding Domain (Dicer-PBD) and the double-strand RNA binding domain (dsRBD) present only in Dcr-1. The phylogenetic trees showed that lepidopteran Dcr-1s or Dcr-2s clustered in one branch, with PxDcr-1 in the basal position and PxDcr-2 closest to Plodia interpunctella Dicer. Two homozygous knockout lines, ΔPxDcr-1 and ΔPxDcr-2, were obtained by using the CRISPR-Cas9 technique. The ΔPxDcr-1 strain exhibited a high mortality rate, a low eclosion rate, a low egg-laying rate, a low hatching rate, and a shriveled ovariole without mature eggs. The ΔPxDcr-2 strain showed no significant difference from the wild-type in terms of survival, development and reproduction, but the RNA interference (RNAi) efficiency caused by dsRNA was significantly reduced. CONCLUSION: These findings demonstrate the involvement of PxDcr-1 in the development and reproduction of P. xylostella, specifically in the formation of ovarioles and eggs, and PxDcr-2 is indispensable for RNAi. These findings shed light on the function of Dcr-1 and Dcr-2 in Lepidoptera. © 2023 Society of Chemical Industry.


Assuntos
Lepidópteros , Animais , Filogenia , Lepidópteros/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , RNA de Cadeia Dupla/genética , Interferência de RNA
4.
Medicine (Baltimore) ; 102(48): e36355, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38050281

RESUMO

RATIONALE: To describe the diagnostic and treatment approaches of renal abscesses complicated with acute pyelonephritis in children. PATIENT CONCERNS: Two children presented with fever, vomiting, and abdominal pain with no typical manifestations, like frequent urination, urgency, dysuria, hematuria, foam urine, and lumbago. Renal abscess complicating acute pyelonephritis was diagnosed by B-ultrasound and computed tomography enhancement. Moreover, inflammatory markers were elevated significantly, but routine blood and urine cultures were repeatedly negative. The empirical anti-infection therapy had no obvious effect. A pathogenic diagnosis was confirmed in case two, and macro gene detection in blood and urine guided the follow-up treatment. DIAGNOSES: Both children were diagnosed with acute gastroenteritis on admission, but renal abscess complicating acute pyelonephritis were diagnosed by imaging examination. INTERVENTIONS: Both children were given anti-infection therapy of third-generation cephalosporin, which had no obvious effect. Routine blood and urine cultures were repeatedly negative. Case one was changed to piperacillin sodium tazobactam. We further carried out blood and urinary metagenomic next-generation sequencing detection for case two. Meanwhile, meropenem and linezolid anti-infection treatment was given. The results showed overlapping infection with Escherichia coli and Enterococcus faecalis. According to the genetic test results, amoxicillin clavulanate potassium combined with nitrofurantoin were prescribed after discharge. OUTCOMES: Clinical symptoms of the 2 children disappeared, the infection was controlled, and imaging showed that renal abscess complicated with acute pyelonephritis disappeared. LESSONS: The clinical spectrum of renal abscess complicating acute pyelonephritis is vague, with no specific manifestations, and can be easily misdiagnosed. B-ultrasound and computed tomography enhancement are helpful in making a definite diagnosis. Moreover, the sensitivity of routine culture is low, and metagenomic next-generation sequencing might be helpful to detect pathogenic microorganisms and guided treatment. Early treatment with broad-spectrum antibiotics might have favorable outcomes.


Assuntos
Nefropatias , Doenças Peritoneais , Pielonefrite , Infecções Urinárias , Criança , Humanos , Abscesso/complicações , Abscesso/diagnóstico , Abscesso/tratamento farmacológico , Pielonefrite/complicações , Pielonefrite/diagnóstico , Pielonefrite/tratamento farmacológico , Infecções Urinárias/diagnóstico , Nefropatias/complicações , Antibacterianos/uso terapêutico , Escherichia coli , Tomografia Computadorizada por Raios X , Doenças Peritoneais/complicações
5.
Int J Mol Sci ; 24(15)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37569697

RESUMO

Piwi proteins play a significant role in germ cell development and the silencing of transposons in animals by associating with small non-coding RNAs known as Piwi-interacting RNAs (piRNAs). While the Piwi gene has been well characterized in various insect species, the role of the Piwi (PxPiwi) gene in the diamondback moth (Plutella xylostella), a globally distributed pest of cruciferous crops, remains unclear. Expression analysis demonstrated the upregulation of PxPiwi in pupae and testes. Furthermore, we generated a PxPiwi-knockout mutant using CRISPR/Cas9 technology, which resulted in a significantly prolonged pupal stage and the failure of pupae to develop into adults. Additionally, the knockdown of PxPiwi, through RNA interference (RNAi), led to a substantial decrease in the oviposition and hatchability of P. xylostella. These findings indicate that PxPiwi is specifically expressed and essential for the development and reproduction of P. xylostella. This is the first report indicating the involvement of the Piwi gene in the development of lepidopteran insects, except for reproduction and germ cell development, which provides a foundation for future investigations into the functions of PxPiwi.


Assuntos
Mariposas , Animais , Feminino , Mariposas/fisiologia , Reprodução/genética , Oviposição , Larva/metabolismo
6.
Opt Express ; 30(14): 24898-24908, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-36237033

RESUMO

Nonsequential double ionization (NSDI) of Argon atoms by counter-rotating two-color elliptically polarized (TCEP) fields is investigated with a three-dimensional classical ensemble model. Different from two-color circularly polarized fields, the combined electric field in TCEP pulses has no symmetry and the ionized electron mainly returns to the parent ion from one direction. Thus the electron momentum distributions show strong asymmetry. Numerical results show with the increase of the relative phase between the two elliptical fields, the return angle of the travelling electron, i.e., the angle between the return direction of the electron and the +x direction, gradually decreases. Moreover, the dominant behavior of electron pairs evolves from anti-correlation to correlation with the relative phase increasing. This provides an avenue to control the return angle and electron correlation behavior by the relative phase between the two elliptical fields.

7.
Biology (Basel) ; 11(10)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36290396

RESUMO

Cyclin-like genes are primarily considered as cell cycle regulators and have shown to be crucial for insect growth, development, reproduction, and fertility. However, no research has been performed on the cyclin-like genes in the diamondback moth (Plutella xylostella). Here, we identified the 21 cyclin genes in the genome of P. xylostella and clustered them into four groups. Most cyclin genes showed a well-maintained gene structure and motif distribution within the same group. The putative promoter regions of cyclin genes contained several transcription binding factors related to reproduction, along with growth and development. Furthermore, 16 miRNAs were identified targeting the 13 cyclin genes. Transcriptome and quantitative real-time PCR (qRT-PCR)-based expression profiling of cyclin-like genes at different stages and tissues were evaluated, revealing that 16 out of 21 cyclin genes were highly expressed in reproductive tissues of adult females and males. The Cyclin B1 gene (PxCyc B1) was only expressed in the ovary of the adult female and selected for the subsequent analysis. RNAi-mediated suppression of PxCyc B1 interrupted the external genitalia and length of the ovariole of female adults. Furthermore, the egg-laying capacity and hatching rate were also significantly decreased by suppressing the PxCyc B1, indicating the importance of cyclin genes in the reproduction and fertility of P. xylostella. The current study explained the detailed genome-wide analysis of cyclin-like genes in P. xylostella, which provided a basis for subsequent research to assess the roles of cyclin genes in reproduction, and the cyclin gene may be considered an effective target site to control this pest.

8.
Wei Sheng Yan Jiu ; 47(1): 80-92, 2018 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-29903228

RESUMO

OBJECTIVE: To assess preadolescents' emotional reactions and intended use of refusal responses to tobacco and ecstasy. METHODS: A total of 333 students from two junior schools in Baise City were recruited with cluster-sampling method, filled the questionnaire to assess a respondent's emotional reactions and refusal skills in response to an offer of tobacco and MDMA from Feb to Jul 2014. RESULTS: 88. 89%-93. 39% of preadolescents would more likely to use "say no"and "tell them you don't want it". A series of 2( type of drug) × 2( offerer) × 2( sex) ANOVAs showed there were main effects for sex in "explicit refusal scale "( F = 8. 391, P = 0. 004), "excuse scale "( F =156. 560, P < 0. 001), "implicit refusal scale "( F = 84. 498, P < 0. 001), "aggression scale"( F = 31. 911, P < 0. 001). For the excuse scale, there were main effects for drug( F = 12. 009, P = 0. 001). A series of χ~2-tests showed that participants were more"curious"to MDMA offers than tobacco offers from close friends and acquaintances( χ~2=13. 76, P = 0. 0003; χ~2= 10. 24, P = 0. 002). For the close friends offers, participants were more "pleasure " to tobacco offers than MDMA offers( χ~2= 8. 33, P = 0. 006). CONCLUSION: There were significant effects of sex and offers in refusal style for drug offers. Preadolescents would show different emotional reaction to type of drug supplier or provider.


Assuntos
Afeto , Emoções , N-Metil-3,4-Metilenodioxianfetamina , Nicotiana , Grupo Associado , Estudantes/psicologia , Criança , Feminino , Humanos , Masculino , Instituições Acadêmicas , Comportamento Social , Inquéritos e Questionários
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