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1.
Plant Dis ; 107(3): 903-907, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36587236

RESUMO

Apple replant disease (ARD) caused by the fungal pathogen Fusarium proliferatum f. sp. malus domestica (Fpmd) MR5 brings annual losses to apple production within China. However, the genomic information of the pathogen is not yet available. Here, we obtained the whole-genome sequence of the highly virulent Fpmd MR5 using the Illumina PE150 platform. The genome size was 42.76 Mb and consisted of 9,047 genes. The GC content was 48.80%, and several genes potentially associated with pathogenicity were identified, such as carbohydrate-active enzymes, secreted proteins, and secondary metabolite gene clusters. There were 260 specific virulence factor genes, mainly related to fungal vegetative growth and the production of cell wall-degrading enzymes. These data will aid future studies investigating host-pathogen interactions and help us develop suitable disease management strategies.


Assuntos
Fusarium , Malus , Malus/microbiologia , Genômica , Virulência/genética
2.
Plant Dis ; 106(11): 2958-2966, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35306841

RESUMO

Apple replant disease (ARD) is the most serious threat facing the apple industry globally. ARD is mainly manifested as decreased plant growth, serious root rot disease, and considerable yield loss. Microbial factors are the dominant factors leading to the occurrence of ARD. Research on soil-borne pathogenic fungi leading to the occurrence of ARD in China is limited. In the present study, we selected 16 replanting orchards from the Northwest Loess region and around the Bohai Gulf. Diseased roots and rhizosphere soil from healthy apple trees and trees showing ARD symptoms were sampled at random. High-throughput sequencing was used to study the fungal communities in the rhizosphere soil, which showed that the composition of the rhizosphere soil fungal community of ARD-symptomatic and healthy apple trees was different. Nectriaceae at the family level and Fusarium at the genus level dominated the rhizosphere soil fungal community in the two regions, while for healthy apple trees, the relative abundance of Mortierella, Minimedusa, Tetracladium, and Chaetomium was higher. Tissue separation and serial dilution were used to separate fungi, and a total of 89 genera and 219 species were obtained, most of which were Fusarium. Fusarium was further confirmed to be the most abundant pathogen species leading to the occurrence of ARD in China through pathogenicity assays. A pathogenicity assay was carried out by the dip-and-cut technique using different host plants. It was found that Fusarium MR5 showed strong aggressiveness to apple rootstocks. Diseased seedlings specifically exhibited chlorosis of the leaves, browning from the edge of the leaf, followed by rolling and yellowing of the leaves, resulting in wilting and eventually death. Strain MR5 was preliminarily identified as F. proliferatum according to the morphological and cultural characteristics. A maximum likelihood analysis of identities based on six gene sequence (ITS, TUB2, IGS, mtSSU, RPB2, and the TEF gene) alignments between the MR5 strain and other strains showed 99 to 100% homology with F. proliferatum. Based on our test results, strain MR5 was identified as F. proliferatum f. sp. malus domestica, which is of great significance for finding new measures to control ARD in China.


Assuntos
Ascomicetos , Fusarium , Malus , Malus/microbiologia , Fusarium/genética , Solo
3.
Zhonghua Gan Zang Bing Za Zhi ; 29(9): 855-860, 2021 Sep 20.
Artigo em Chinês | MEDLINE | ID: mdl-34638204

RESUMO

Objective: To analyze the clinical value and predictive difference of serum Golgi protein 73 (GP73) and serum autophagy-related protein p62 levels in the short-term prognosis of patients with hepatitis B virus-related acute-on-chronic liver failure (ACLF). Methods: Clinical data of admitted cases to our hospital from October 2018 to April 2020 were retrospectively analyzed. Simultaneously, there were 32 cases with HBV-related ACLF in group A, 65 cases with hepatitis B virus-related cirrhosis in group B and C (Child-Pugh Class A, 34 cases as B group, and Child-Pugh B/C class, 31 cases as group C), and another 30 healthy subjects served as the control group (group D). The serum GP73 and p62 levels of the four selected groups were measured. ACLF group patients were followed up for 3 months to analyze the prognosis of the patients. The serum GP73 and p62 levels of patients who died and survived during hospitalization were compared. The data were analyzed by one-way analysis of variance, independent sample t-test, and Pearson's correlation analysis. Receiver operating characteristic curve (ROC) was used to analyze the predictive value of GP73 and p62 levels in surviving patients. Results: GP73 levels in the four groups A, B, C and D were (284.30 ± 70.55) ng/ml, (125.33 ± 20.57) ng/ml, (159.82 ± 31.20) ng/ml, and (45.46 ± 10.22) ng/ml, respectively. The p62 levels were (1.30 ± 0.35) ng/ml, (2.88 ± 0.58) ng/ml, (2.02 ± 0.545) ng/ml, and (4.68 ± 1.03) ng/ml, respectively. GP73 detection value was significantly higher in group A than the other three groups (P < 0.05). Group D had significantly lower value than the other three groups (P < 0.05), and group C had significantly higher value than group B (P < 0.05). The detection value of p62 in group A was significantly lower than the other three groups (P < 0.05). Group D had significantly higher value than the other three groups (P < 0.05), and group B had slightly higher value than group C, and the differences were statistically significant (P < 0.05). There was a negative correlation between GP73 and p62 (r = -0.695, P < 0.001). Survived patients GP73 level in the ACLF group was significantly lower than dead patients [(212.17 ± 22.47) ng/ml and (340.08 ± 32.91) ng/ml, t = 12.493, P < 0.05], and p62 level was significantly higher than dead patients [(1.46 ± 0.28) ng/ml and (1.18 ± 0.35) ng/ml, t = 2.445, P < 0.05]. According to the ROC curve analysis results, the area under the curve (AUC) of GP73 was 0.865, the AUC of p62 was 0.750, and the combined AUC of the both was 0.968. Conclusion: Both GP73 and p62 have a certain predictive value for the short-term prognosis of HBV-related ACLF patients, but the combination of the two indicators has a higher predictive value.


Assuntos
Insuficiência Hepática Crônica Agudizada , Carcinoma Hepatocelular , Neoplasias Hepáticas , Insuficiência Hepática Crônica Agudizada/diagnóstico , Vírus da Hepatite B , Humanos , Proteínas de Membrana , Prognóstico , Estudos Retrospectivos
4.
J Phys Condens Matter ; 31(41): 415702, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31220819

RESUMO

The circular (CPGE) and linear photogalvanic effect (LPGE) of a three-dimensional topological insulator Bi2Se3 thin film of seven quintuple layers excited by near-infrared (1064 nm) and mid-infrared (10.6 [Formula: see text]m) radiations have been investigated. The comparison of the CPGE current measured parallel and perpendicular to the incident plane, together with the comparison of the CPGE current under front and back illuminations, indicates that the CPGE under front illumination of 1064 nm light is dominated by the top surface states of the Bi2Se3 thin film. The CPGE current excited by 10.6 [Formula: see text]m light is about one order larger than that excited by 1064 nm light, which may be attributed to the smaller cancelation effect of the CPGE generated in the two-dimensional electron gas when excited by 10.6 [Formula: see text]m light. Under the excitation of 1064 nm light, the LPGE current is dominated by the component which shows an even parity of incident angles, while the LPGE current excited by 10.6 [Formula: see text]m light is mainly contributed by the component which is an odd parity of incident angles. Both of the CPGE and LPGE currents excited by 1064 nm decrease with increasing temperature, which may be owing to the decrease of the momentum relaxation time and the stronger electron-electron scattering with increasing temperature, respectively.

5.
Bone Joint Res ; 6(11): 612-618, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29092816

RESUMO

OBJECTIVES: This study looked to analyse the expression levels of microRNA-140-3p and microRNA-140-5p in synovial fluid, and their correlations to the severity of disease regarding knee osteoarthritis (OA). METHODS: Knee joint synovial fluid samples were collected from 45 patients with OA of the knee (15 mild, 15 moderate and 15 severe), ten healthy volunteers, ten patients with gouty arthritis, and ten with rheumatoid arthritis. The Kellgren-Lawrence grading (KLG) was used to assess the radiological severity of knee OA, and the patients were stratified into mild (KLG < 2), moderate (KLG = 2), and severe (KLG > 2). The expression of miR-140-3p and miR-140-5p of individual samples was measured by SYBR Green quantitative polymerase chain reaction (PCR) analysis. The expression of miR-140-3p and miR-140-5p was normalised to U6 internal control using the 2-△△CT method. All data were processed using SPSS software. RESULTS: Expression of both miR-140-3p and miR-140-5p was downregulated in OA synovial fluid, showing a statistical difference between the OA and non-OA group, and increased OA severity was associated with a decreased expression of miR-140-3p or miR-140-5p. The Spearman rank correlation analysis suggested that the expression of miR-140-3p or miR-140-5p was negatively correlated with OA severity. In addition, the expression of miR-140-5p was 7.4 times higher than that of miR-140-3p across all groups. CONCLUSION: The dysregulation of miR-140-3p and miR-140-5p in synovial fluid and their correlations with the disease severity of OA may provide an important experimental basis for OA classification, and the miR-140-3p/miR-140-5p are of great potential as biomarkers in the diagnosis and clinical management of patients with OA.Cite this article: C-M. Yin, W-C-W. Suen, S. Lin, X-M. Wu, G. Li, X-H. Pan. Dysregulation of both miR-140-3p and miR-140-5p in synovial fluid correlate with osteoarthritis severity. Bone Joint Res 2017;6:612-618. DOI: 10.1302/2046-3758.611.BJR-2017-0090.R1.

6.
Zhonghua Fu Chan Ke Za Zhi ; 52(5): 320-326, 2017 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-28545270

RESUMO

Objective: To detect mutations of p53 gene 2-4 exons from peripheral blood and to explore their relevance in HPV16-positive cervical cancer susceptibility and clinical significance. Methods: Collected firstly cases from the Third Affiliated Hospital of Kunming Medical University from October 2012 to April 2014, included 167 cases HPV16-postive cervical cancer and 160 cases HPV-negative healthy women. Genomic DNA from the host peripheral venous blood was taken, mutations of p53 gene 2-4 exons were analyzed with software DNAstar after PCR and bidirectional sequencing. Meanwhile, mutations of p53 gene 2-4 exons among different clinicopathological characteristics in HPV16-postive cervical cancer were distinguished. Results: (1) Three mutations and an 16-bp insertion/deletion sequences were found in p53 gene exons 2-4, included C/G mutation of single nucleotide polymorphism (SNP) 11827 in intron2, A/C mutation of SNP11992 in intron3, C/G mutation in codon 72 (rs1042522) of exon4 and 16-bp (acctggagggctgggg) repeat insertion or deletion in intron3 (rs17878362), while deletion recorded as A1, insertion recorded as A2. No significant differences were found in each point allele and genotype frequency (P>0.05) . (2) Stratified analysis for cervical cancer group resulted with some differences. Compared group of non-squamous carcinoma with squamous carcinoma group, there were obviously decreased in allete A2 [11.8% (4/34) vs 3.5% (10/284) ; χ(2)=4.90, P=0.027], genotype A1A2 [4/17 vs 7.0% (10/142) ; χ(2)=5.14, P=0.023], and haplotype C-A2 [11.8% (4/34) vs 3.5% (10/284) ; χ(2)=4.91, P=0.027]. Compared with poorly differentiated group, allele C of SNP11827 and rs1042522 were obviously decreased in medium high differentiation group [50.8% (61/120) vs 38.8% (62/160) ; χ(2)=4.07, P=0.044], while haplotype G-A1 were apparently higher [49.2% (59/120) vs 61.2% (98/160) ; χ(2)=4.07, P=0.044], genotype GG of SNP11827 and rs1042522 were obviously decreased in superficial myometrial invasion depth group than that in deep myometrial invasion depth group [46.3% (25/54) vs 21.1% (8/38) ; χ(2)=7.06, P=0.029]. No significant differences were found between stage Ⅰ and Ⅱ, pelvic lymph node metastasis or not (all P>0.05) . Conclusions: No obvious correlation is found between polymorphisms in exons 2-4 of p53 gene and susceptibility of HPV16-postive cervical cancer. But the patient with allete C and A2, genotype GG and A1A2, haplotype C-A2 and G-A1 may be increase risk of poorly differentiation, deep muscular invasion and bad pathological type. Analysis of p53 gene polymorphism may be provide a basis for the prognosis evaluation and individualized treatment of cervical cancer.


Assuntos
Carcinoma de Células Escamosas/patologia , Colo do Útero/virologia , Genes p53 , Predisposição Genética para Doença , Papillomavirus Humano 16 , Polimorfismo de Nucleotídeo Único , Neoplasias do Colo do Útero/patologia , Alelos , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/virologia , Códon , DNA de Neoplasias/análise , DNA Viral/análise , Éxons , Feminino , Regulação Neoplásica da Expressão Gênica , Genótipo , Papillomavirus Humano 16/genética , Humanos , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase , Prognóstico , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/virologia
7.
Phys Rev Lett ; 101(14): 147402, 2008 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-18851572

RESUMO

Under normal incidence of circularly polarized light at room temperature, a charge current with swirly distribution has been observed in the two-dimensional electron gas in Al{0.25}Ga{0.75}N/GaN heterostructures. We believe that this anomalous charge current is produced by a radial spin current via the reciprocal spin Hall effect. It suggests a new way to research the reciprocal spin Hall effect and spin current on the macroscopic scale and at room temperature.

8.
J Insect Physiol ; 48(7): 733-741, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12770068

RESUMO

In Phormia regina, the rate of juvenile hormone (JH) synthesis rises rapidly after the ingestion of an adequate protein meal. In a previous publication we have localized the neurons containing Manduca sexta allatotropin (Mas-AT)-like substances in the brain of P. regina and demonstrated the allatotropic effect of synthetic Mas-AT in sugar-fed flies in vitro. In this current study, we examined the possible role of the brain of P. regina after the fly received a protein meal. In vitro studies showed that the brain releases, at 8 h after a protein meal, a factor(s) with a strong allatotropic effect. This factor(s) stimulates the corpus allatum (CA) to produce 6.9 times more juvenile hormones (JHs) than the control CA. Time course studies showed that the release of this allatotropic factor(s) is temporally controlled. Only the brains collected from flies at 6 and 8 h after the onset of a liver meal release allatotropic factor(s). Injection of anti-Mas-AT antiserum partially suppressed the fly follicle development in vivo. Presence of anti-Mas-AT antiserum decreased the allatotropic effect of the brain released allatotropic factor(s) in vitro. In addition to a Mas-AT-like substance, it is possible that the brains of liver-fed P. regina females may synthesize other allatotropic factors that are chemically unrelated or partially related to Mas-AT, which cannot be recognized/neutralized by our anti-Mas-AT antiserum.

9.
Science ; 292(5514): 107-10, 2001 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-11292875

RESUMO

The Drosophila melanogaster gene insulin-like receptor (InR) is homologous to mammalian insulin receptors as well as to Caenorhabditis elegans daf-2, a signal transducer regulating worm dauer formation and adult longevity. We describe a heteroallelic, hypomorphic genotype of mutant InR, which yields dwarf females with up to an 85% extension of adult longevity and dwarf males with reduced late age-specific mortality. Treatment of the long-lived InR dwarfs with a juvenile hormone analog restores life expectancy toward that of wild-type controls. We conclude that juvenile hormone deficiency, which results from InR signal pathway mutation, is sufficient to extend life-span, and that in flies, insulin-like ligands nonautonomously mediate aging through retardation of growth or activation of specific endocrine tissue.


Assuntos
Envelhecimento/fisiologia , Proteínas de Transporte/genética , Proteínas de Transporte/fisiologia , Corpora Allata/metabolismo , Proteínas de Drosophila , Drosophila melanogaster/fisiologia , Longevidade/fisiologia , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/fisiologia , Receptores Proteína Tirosina Quinases , Alelos , Animais , Drosophila melanogaster/genética , Feminino , Fertilidade , Genes de Insetos , Genótipo , Insulina/farmacologia , Hormônios Juvenis/metabolismo , Masculino , Metoprene/farmacologia , Mutação , Receptor de Insulina/genética , Receptor de Insulina/fisiologia , Reprodução , Transdução de Sinais , Superóxido Dismutase/metabolismo , Triglicerídeos/metabolismo , Vitelogênese/efeitos dos fármacos
10.
J Comp Neurol ; 421(1): 136-42, 2000 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-10813776

RESUMO

Antibody to the dipteran myosuppressin peptide, dromyosuppressin, TDVDHVFLRFamide, stained cells and fibers in the brain, optic lobes, subesophageal ganglion, and thoracico-abdominal ganglion of the blow fly, Phormia regina (Meigen). Dromyosuppressin-like immunoreactive fibers were detected in the cardiac recurrent nerve, hypocerebral ganglion/corpora cardiaca complex, crop duct, and crop. In order to explore the mechanisms involved in regulating crop movement, we established an in vitro bioassay. The basal rate of crop movement was 50.8 +/- 1.5 contractions per minute. Application of 1 microl of saline to the crop did not significantly affect the rate of movement compared to the basal rate (46.1 +/- 1.1 contractions per minute, P < 0.05). Application of 1 microl 10(-6) M dromyosuppressin or 1 microl 10(-3) M benzethonium chloride to the crop slowed the rate to 2.2 +/- 0.2 and 6.1 +/- 0.7 contractions per minute, respectively. Although other data have previously been interpreted to suggest that dipteran crop contractions do not include a neural component, the neuropeptide dromyosuppressin affected P. regina crop motility. Innervation of the crop and crop duct by dromyosuppressin immunoreactive processes that originated in the central nervous system and the effect of dromyosuppressin on crop muscle contractions suggest that dromyosuppressin is released locally to modulate crop contractions and that crop motility is under neural regulation. Myosuppressins isolated from numerous insects have a high degree of structure identity and reduce spontaneous muscle contractions of the hindgut, oviduct, and heart. Benzethonium chloride, previously identified as a myosuppressin agonist on the cockroach hindgut and locust oviduct, mimicked the effect of dromyosuppressin on the crop. This suggests that structural requirements for myosuppressin receptor binding in the cockroach hindgut, locust oviduct, and fruit fly crop are similar.


Assuntos
Benzetônio/farmacologia , Sistema Digestório/inervação , Dípteros/fisiologia , Hormônios de Inseto/fisiologia , Neuropeptídeos/fisiologia , Animais , Química Encefálica , Sistema Digestório/efeitos dos fármacos , Sistema Digestório/crescimento & desenvolvimento , Feminino , Gânglios dos Invertebrados/citologia , Gânglios dos Invertebrados/efeitos dos fármacos , Gânglios dos Invertebrados/metabolismo , Motilidade Gastrointestinal/fisiologia , Imuno-Histoquímica , Hormônios de Inseto/metabolismo , Contração Muscular/fisiologia , Fibras Nervosas/fisiologia , Neuropeptídeos/metabolismo
11.
J Insect Physiol ; 45(9): 815-822, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12770294

RESUMO

Both dietary protein and the corpus allatum (CA) were required for normal mating behavior in both male and female black blow fly, Phormia regina (Meigen). Nutrition (protein diet) activated the CA in both sexes. More than 10 mg of dietary liver was required for each male to result in 80% insemination of females, while 20 mg of liver was required for each female to allow 78% of females to become inseminated. Between 10 to 15 mg of protein meal (i.e., liver) was required to activate sexual receptivity in 71% of the females, while between 15 to 20 mg of liver was needed to support full oöcyte development in 70% of the females (Yin, C.-M., Zou, B.-X., Li, M.-F., Stoffolano, J.G., Jr. 1994. Discovery of a midgut peptide hormone which activates the endocrine cascade leading to oogenesis in Phormia regina Meigen. Journal of Insect Physiology, 40, 283-292). Allatectomy suppressed mating behavior more than 2-fold in both sexes. Topical application of 10 &mgr;g of S-methoprene (a juvenile hormone analogue) at 12 h after the onset of liver feeding restored sexual activity of both allatectomized males and females. Incidence of successful insemination increased as the oöcyte development progressed. Ovariectomy suppressed sexual receptivity more than 3-fold in liver-fed females. Thus, in addition to nutrition and the CA, ovaries and their developmentaal status can also affect the sexual receptivity in female P. regina.

12.
J Insect Physiol ; 43(6): 533-540, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12770415

RESUMO

Neck-ligation, brain implantation, allatectomy, methoprene treatment, and ovariectomy indicated that the disappearance of pupal fat body cells in newly emerged adult female blow fly, Phormia regina, is controlled by the brain and the corpus allatum (CA). Absence of brain or CA greatly lowered the rate of fat body cell disappearance (i.e. death). Dependency on the CA decreased from 0 to 36h post-emregence, indicating that the CA was active during the earlier part of this timespan. Methoprene treatment enhanced pupal fat body cell disappearance in allatectomized females. Brain implantation restored the rate of pupal fat body cell disappearance in neck-ligated flies. Brains from day 1 sugar-fed flies proved to be more effective than those from day 2 sugar-fed flies, indicating that there may be a window after adult emergence that allows the brain to act directly or indirectly on the death of pupal fat body cells. Ovariectomy did not alter the rate of pupal fat body cell death in test animals. Dying pupal fat body cells were smaller in size, less dense (i.e. did not sink in saline like normal pupal fat body cells), and stickier (i.e. attached to other tissues tighter) than the healthy cells. A possible role played by ecdysteroids is also discussed.

13.
Mol Cell Endocrinol ; 127(1): 109-16, 1997 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-9099906

RESUMO

We previously reported that a deficiency in prothoracicotropic hormone (PTTH) transduction during the early last larval instar of Bombyx mori plays a role in leading to very low ecdysteroid levels in the hemolymph, inactivation of corpora allata, as well as larval-pupal transformation. In the present study, the role of juvenile hormone (JH) in the regulation of PTTH transduction was clarified. When JH analog (hydroprene) was applied to early last instar larvae, the development of larvae was greatly inhibited. It was found that it was not PTTH release, but prothoracic gland competency in both cAMP generation and ecdysteroidogenesis to the stimulation of PTTH which was developmentally inhibited by hydroprene application. Glands in hydroprene-treated larvae showed no response in ecdysteroidogenesis to either PTTH or 1-methyl-3-isobutylxanthine (MIX) until day 7, 4 days later than those of control larvae. JH-I application showed the same effects as those of hydroprene. By contrast, allatectomy on day 0 of the last instar accelerated development, and glands showed the activation response to either PTTH or MIX in both cAMP generation and ecdysteroidogenesis 1 day after allatectomy. From these results, we conclude that the absence of JH is a prerequisite for successful PTTH transduction and for acquisition of the cAMP generating system of gland cells.


Assuntos
Bombyx/efeitos dos fármacos , AMP Cíclico/metabolismo , Ácidos Graxos Insaturados/farmacologia , Hormônios de Inseto/metabolismo , Hormônios Juvenis/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Bombyx/embriologia , Hormônios de Inseto/genética , Larva/efeitos dos fármacos
14.
J Insect Physiol ; 43(11): 1065-1076, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12770478

RESUMO

The cuticular hydrocarbons from adult Phormia regina (Meigen) were characterized by gas chromatography-mass spectrometry. Both sexes had similar components in nearly identical quantities, consisting of complex mixtures of saturated n-, monomethyl- and dimethylalkanes from 23 to 33 total carbons. Although no diet-, age-, or sex-specific differences were observed, cuticular hydrocarbons were shown to be involved in copulatory behavior. Hydrocarbon profiles of wild, compared to laboratory reared flies, showed no major differences. Behaviorally, males responded the same to dead decoys of either sex. Removal of the hydrocarbons, using hexane, from either male or female decoys, did not affect the number of mating strikes, but markedly reduced the number of copulatory attempts and the amount of time males spent mounted on either decoy. House fly, Musca domestica L., males when paired with a female M. domestica decoy produced copulatory attempts: whereas, when P. regina males were placed with M. domestica female decoys, there were no copulatory attempts. It is concluded that the cuticular hydrocarbons of P. regina function as species-specific but not sex-specific mating cues and elicit species-specific copulatory behavior in males.

15.
J Gen Virol ; 77 ( Pt 3): 547-54, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8601794

RESUMO

The baculovirus Lymantria dispar nuclear polyhedrosis virus interferes with insect larval development by altering the host's hormonal system. The level of haemolymph ecdysteroids, the insect moulting hormone, was found to be higher in virus-infected larvae than in uninfected controls. This was consistently observed in both fourth instars and day 5-infected fifth instars. The rate of hormone synthesis was examined by in vitro incubation of the prothoracic gland. Gland activity in virus-infected larvae was higher than controls and continued until the late stages of virus infection, even during the time that controls had ceased to secrete ecdysone after moulting. During virus replication, the prothoracic gland was observed to maintain morphological and ultrastructural characteristics indicative of ecdysone biosynthetic activities. Therefore, it is likely that the insects are no longer under the control of the normal hormonal system after virus infection. It is felt that the alteration of hormone titre and the rate of ecdysone synthesis is the result of the activity of ecdysteroid UDP-glucosyl transferase (EGT), a virus-encoded enzyme which is thought to inactivate ecdysteroids by sugar conjugation.


Assuntos
Hormônios de Inseto/sangue , Mariposas/virologia , Nucleopoliedrovírus/fisiologia , Esteroides/sangue , Animais , Ecdisteroides , Glândulas Endócrinas/crescimento & desenvolvimento , Glândulas Endócrinas/metabolismo , Glândulas Endócrinas/ultraestrutura , Glândulas Endócrinas/virologia , Hemolinfa/metabolismo , Mariposas/enzimologia , Mariposas/crescimento & desenvolvimento , Replicação Viral
16.
Med Vet Entomol ; 9(4): 388-92, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8541589

RESUMO

Fresh beef liver, sugar, and five different types of faeces were evaluated as supportive diets for egg development in the blowfly Phormia regina. Females on a sugar diet were unable to develop follicles beyond stage 3, whereas liver proved to be the best diet for complete egg maturation. Some faecal diets were unable to support egg maturation when fed upon for a short period of time; however, longer periods of feeding produced complete egg maturation. The necessity to feed for longer periods of time in order to produce eggs on most of these diets was attributed to their low protein content. Males, in a shorter period of time than females, obtained enough protein from faeces to activate the neuroendocrine system involved in mating.


Assuntos
Dípteros/fisiologia , Animais , Fezes , Comportamento Alimentar , Feminino , Inseminação , Masculino , Ovário , Proteínas/metabolismo , Reprodução
17.
J Med Entomol ; 32(2): 190-4, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7608926

RESUMO

To study the role of the crop in protein storage, crop and midgut filling in female Phormia regina (Meigen) was measured volumetrically and the soluble protein content determined. During a 4-h feeding period on homogenized liver, nonligated females consumed and stored enough protein in the crop and midgut to develop a normal compliment of eggs. Within 26 h from the onset of feeding, 75% of the protein content of the crop and a similar amount from the midgut were emptied. Neck ligation or sham neck ligation 7 h after females fed to repletion slowed but still allowed delivery of sufficient protein for egg development.


Assuntos
Sistema Digestório/metabolismo , Dípteros/metabolismo , Proteínas/metabolismo , Animais , Feminino , Fígado , Masculino
18.
J Morphol ; 225(3): 369-376, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29865341

RESUMO

The corpora allata in adult Loreyi leafworms Leucania loreyi (Lepidoptera: Noctuidae) exhibit sexual dimorphism. The male possesses right and left corpora allata of about the same size. Each gland is composed of a cluster of approximately 40 semi-transparent, spherical, isolated cells held together by fine tracheae and nerve fibers. The largest cell diameter found in male glands was 203 pm. In contrast, the female gland cells and clusters are much smaller. The largest dimensions of one whole female gland cluster were 452 µm in length and 280 µm in width. Using bilateral and unilateral larval allatectomy, we confirmed that the adult isolated cell type glands develop ontogenetically from larval capsular type glands. Ultrastructural study re- vealed many similarities between the subcellular structures of the isolated cell type glands of L. loreyi and the more common capsular gland reported by others. These similarities include very large numbers of mitochondria, abun- dant whorled smooth endoplasmic reticulum, irregularly shaped nuclei, Golgi bodies, and free ribosomes. Compared with the corpora allata of 3- to 9-day-old adults, the glands of 1-day-old adults possessed much less smooth endoplasmic reticulum. The gland cells in females usually have more neurosecretory nerve endings, less-abundant stacked smooth endoplasmic reticulum, and less- defined interdigitations than the gland cells in males. © 1995 Wiley-Liss, Inc.

19.
J Chem Ecol ; 18(5): 749-60, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-24253968

RESUMO

The diel periodicity of sex pheromone titer from pheromone glands of femaleLymantria dispar is described. On the day of emergence (day 0), pheromone titer was generally low; means ranged from 1 to 4 ngcis- 7,8-epoxy-2-methyloctadecane during photophase and gradually increased to 8.4 ng over the course of scotophase. For day-1, -2, and -3 females, the diel fluctuations of titer were more pronounced. Lowest titers (5-9 ng) occurred 0-4 hr after lights-on, and peak titers (19-32 ng) were found 0-4 hr before lights-off. Comparison of the average daily titer among the different age groups (data pooled over six time points at 4-hr intervals) indicated that significantly less pheromone was extracted from glands of day-0 (4.5 ng) than day-1 (12.4 ng), day-2 (15.4 ng), or day-3 females (13.5 ng). No significant differences were found among the three older ages. Femalesin copula exhibited a rapid reduction in titer within the first 0.5 hr of mating initiation (7.6 ng vs. 19.5 ng from virgin females of similar age). After the second 0.5 hr, the reduction in titer was not nearly as marked, falling only to 4.5 ng. Twenty-four hours after mating, titer fell below the limits of detection (0.5 ng). All extracts from pheromone glands of virgin or mated females contained < 1.0 ng of the putative pheromone precursor, 2-methyl-cis-7-octadecene.

20.
Life Sci ; 40(17): 1725-30, 1987 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-3561173

RESUMO

Cortisol increased growth and differentiation in the large milkweed insect (Oncopeltus fasciatus). The glucocorticoid significantly increased the growth of the insect as analyzed by wet and dry weights. Cortisol also stimulated the development of the insects over that of the controls during the six day bioassay.


Assuntos
Glucocorticoides/farmacologia , Hemípteros/crescimento & desenvolvimento , Mineralocorticoides/farmacologia , Aldosterona/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Cortodoxona/farmacologia , Desoxicorticosterona/análogos & derivados , Desoxicorticosterona/farmacologia , Hemípteros/efeitos dos fármacos , Hidrocortisona/farmacologia , Larva/efeitos dos fármacos
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