首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
The spotted lanternfly, Lycorma delicatula, (Hemiptera, Fulgoridae) is an invasive pest to Korea and the United States, originating from China or Southeast Asia. Immature L. delicatula feed on a wide range of plants, but the adults are more host-selective, often preferring the tree of heaven, Ailanthus altissima. We performed field studies to evaluate adult movement in relation to A. altissima after disturbance. The Ailanthus trees were in a mixed suburban forested situated at the southern border of an open grassy field. Female adult lanternflies were manually disturbed from feeding on the trunks of large A. altissima trees. In the first experiment, insects were disturbed directly from the tree using a ballpoint pen to simulate a predatory attack. These insects usually flew initially southward away from the tree line toward a sunlit field, but turned northward back toward the tree line. In the second experiment, to simulate an initially successful predatory attack, they were manually taken from trees, and allowed to escape. The females immediately opened their wings in an apparent aposematic display. They then either immediately flew toward the sunlit open field, or remained with their wings splayed open for a prolonged period.  相似文献   

2.
Parent-offspring conflict—conflict over resource distribution within families due to differences in genetic relatedness—is the biological foundation for many psychological phenomena. In genomic imprinting disorders, parent-specific genetic expression is altered, causing imbalances in behaviors influenced by parental investment. We use this natural experiment to test the theory that parent-offspring conflict contributed to the evolution of vocal music by moderating infant demands for parental attention. Individuals with Prader-Willi syndrome, a genomic imprinting disorder resulting from increased relative maternal genetic contribution, show enhanced relaxation responses to song, consistent with reduced demand for parental investment (Mehr, Kotler, Howard, Haig, & Krasnow, 2017, Psychological Science). We report the necessary complementary pattern here: individuals with Angelman syndrome, a genomic imprinting disorder resulting from increased relative paternal genetic contribution, demonstrate a relatively reduced relaxation response to song, suggesting increased demand for parental attention. These results support the extension of genetic conflict theories to psychological resources like parental attention.  相似文献   

3.
We present a theory of the origin and evolution of infant-directed song, a form of music found in many cultures. After examining the ancestral ecology of parent-infant relations, we propose that infant-directed song arose in an evolutionary arms race between parents and infants, stemming from the dynamics of parent-offspring conflict. We describe testable predictions that follow from this theory, consider some existing evidence for them, and entertain the possibility that infant-directed song could form the basis for the development of other, more complex forms of music.  相似文献   

4.
AimDental enamel, the most rigid biological tissue of the tooth known to mankind, is the most integral and fundamental part of the tooth. Enamel matrixes compile 5% of Enamelin peptides and at the time of tooth development, they are considered to effect the formation and elongation of enamel crystallites. ENAM plays critical role in enamel formation. Any changes in ENAM may affect the thickness of enamel and may lead to dental caries. The present study is aimed to evaluate the association of ENAM gene polymorphisms and susceptibility of dental caries development risk.Material and methodsThe present study was carried out on 168 South Indian children, children’s with dental caries were included in study. Written consent was taken from their parents/guardians. Additionally 193 healthy individuals were enrolled as controls. Sampling was done after dental examination of the individuals. Three ENAM gene single nucleotide polymorphisms (SNPs) were rs7671281, rs3796704 and rs12640848 was genotyped to check their role in susceptibility of dental caries development risk.ResultsOut of three SNPs rs7671281 showed statistically significant risk association with dental caries susceptibility in this ethnic population at heterozygous allele CT (OR: 1.939, p = .01865) and with minor allele T (OR: 1.451, p = .001292). SNP rs3796704 showed significant protective association with dental caries in Indian population at heterozygous allele GA (OR: 0.409, p = .0192) and with minor allele A (OR: 0.645, p = .00875). SNP rs12640848 showed significant protective association with dental caries in Indian population at heterozygous allele AG (OR: 3.041, p = .00642) and with minor allele G (OR: 1.478, p = .02184). Preliminary insilico analysis also showed that rs7671281 (Ile648Thr) amino acid change will cause the structural and functional changes in ENAM protein.ConclusionsIn the present study significant association was observed between ENAM gene SNP rs7671281 and dental caries susceptibility in South Indian children. These results suggested that ENAM gene variants may contribute to dental caries in children.  相似文献   

5.
The mechanism for more frequent ovulation from right ovary (RO) than left ovary (LO) was considered by determining if RO of recently born calves had a propensity for more follicles. Rationale was from reports that RO in heifers has more 6-mm follicles before selection of the future ovulatory follicle as well as greater frequency of RO ovulation. Dimensions, weight, and number of follicles per ovary were compared between LO and RO in 10 Holstein calves (age, 1 to 7 days). Weight of an ovary was greater (P < 0.05) for RO (0.393 ± 0.04 g) than LO (0.355 ± 0.05 g). Follicles were delineated by translucency of follicular fluid from transmitted light. Follicles from 0.3 mm diameter (smallest identified) to 4.8 mm (largest present) were counted. Mean number of translucent antral follicles (8.1 ± 1.8 vs 5.3 ± 1.2 follicles) and means for follicle diameter, fluid volume, and surface area were each greater (P < 0.01) for RO than LO. Combined for all diameters (0.3–4.8 mm), the hypothesis was supported that more follicles are present in RO than LO in calves 1 to 7 days of age. Although follicle activity in the fetus has not been compared between LO and RO, more follicles in RO than LO in recently born calves is consistent with the concept that the propensity for RO ovulation is congenital.  相似文献   

6.
Mutations in the gene triosephosphate isomerase (TPI) lead to a severe multisystem condition that is characterized by hemolytic anemia, a weakened immune system, and significant neurologic symptoms such as seizures, distal neuropathy, and intellectual disability. No effective therapy is available. Here we report a compound heterozygous patient with a novel TPI pathogenic variant (NM_000365.5:c.569G>A:p.(Arg189Gln)) in combination with the common (NM_000365.5:c.315G>C:p.(Glu104Asp)) allele. We characterized the novel variant by mutating the homologous Arg in Drosophila using a genomic engineering system, demonstrating that missense mutations at this position cause a strong loss of function. Compound heterozygote animals were generated and exhibit motor behavioural deficits and markedly reduced protein levels. Furthermore, examinations of the TPIArg189Gln/TPIGlu104Asp patient fibroblasts confirmed the reduction of TPI levels, suggesting that Arg189Gln may also affect the stability of the protein. The Arg189 residue participates in two salt bridges on the backside of the TPI enzyme dimer, and we reveal that a mutation at this position alters the coordination of the substrate-binding site and important catalytic residues. Collectively, these data reveal a new human pathogenic variant associated with TPI deficiency, identify the Arg189 salt bridge as critical for organizing the catalytic site of the TPI enzyme, and demonstrates that reduced TPI levels are associated with human TPI deficiency. These findings advance our understanding of the molecular pathogenesis of the disease, and suggest new therapeutic avenues for pre-clinical trials.  相似文献   

7.
8.
The feeding preference of pear psylla (Cacopsylla chinensis) varies among pear cultivars. To clarify whether leaf structural factors are related to C. chinensis resistance, eleven pear cultivars of three pear species and their hybrids in China were studied. The population size of C. chinensis in plots of different cultivars was investigated, and leaf paraffin sections of each pear cultivar were observed. Correlation analysis results showed that the thickness of palisade tissue (PT) and the thickness ratio (TR) of PT to leaf (L) were the main factors influencing resistance to C. chinensis. The leaves of cultivar Wujiuxiang and those species from France and the USA exhibited the thickest PT and the highest TR; these three cultivars demonstrated much higher resistance to C. chinensis than did the other cultivars. The cultivar Gold Nijisseiki, with a large C. chinensis population size, showed low PT and TR. The findings of this study may provide valuable information to pear growers, experts and scientists regarding plant protection, cultivation and breeding when selecting suitable varieties to culture from the perspective of pest control.  相似文献   

9.
Research has indicated that serotonin (5-HT) modulates non-associative learning in a variety of invertebrate species. Recent work has demonstrated that the terrestrial hermit crab is a suitable animal model for non-associative learning phenomena, including habituation, sensitization, and dishabituation. We examined the potential role of a non-selective 5-HT antagonist, methysergide, in non-associative learning in the hermit crab. We administered methysergide prior to delivering repeated stimulus presentations of a looming visual predator. We found evidence for more rapid habituation relative to a control condition in which crabs did not receive the drug. These results indicate a role for 5-HT in the defensive behavior of the hermit crab and importantly, suggest a conserved role for 5-HT in modulating basic learning processes in invertebrates.  相似文献   

10.
Lablab bean (Lablab purpureus) is a popular vegetable crop in Bangladesh, but farmers growing this crop experience significant losses to insect pests despite heavy reliance on conventional insecticides. We conducted field studies to improve pest management in lablab bean by testing biorational insecticides as alternatives to conventional insecticides for the control of pod borers (Maruca vitrata) and aphids (Aphis craccivora), and characterizing flower-inhabiting thrips as an emerging pest in this crop. In field experiments, spinosad was the most promising biorational we tested, suppressing pod-boring caterpillars more effectively than thiamethoxam or quinalphos. In contrast, azadirachtin (neem) did not significantly suppress any of the insect pests we measured, although target aphid populations were generally low at our research site. Using DNA barcoding at the coxI locus combined with morphological identification, we found eight thrips taxa inhabiting lablab bean flowers, dominated by Megalurothrips usitatus and M. distalis/peculiaris. A preliminary regression analysis indicated that these flower-inhabiting thrips reduced lablab bean yield. Our results suggest that spinosad may be useful within lablab bean IPM programs, and that these programs will likely need to incorporate tactics against thrips to effectively protect yield. Finally, we found that DNA barcoding was a valuable tool for pest identification in an understudied crop and region, but that to reach its full potential will require an investment in more comprehensive reference libraries.  相似文献   

11.
For the first time a finger print analysis via high-performance thin layer chromatography (HPTLC) of Boswellia Sp. Burseraceae was accomplished. A preliminary investigation of the Boswellia Sp. Burseraceae displayed the presence of chemical constituents that could be involved in the production of innovative pharmaceuticals for an array of antiviral, anticancer, and antibacterial uses. Moreover, the finger print analysis would deem useful for establishing HPTLC standardization for natural and herbal photochemical constituents.  相似文献   

12.
This first ever study was carried out to explore the floristic composition of protected and unprotected forests of Sathan Gali, District Mansehra, KP, Pakistan. The study area being the part of the Western Himalayas harbours rich floristic diversity. In the current investigation, an effort was made to record primary data about floral diversity of the area. The study area was visited recurrently during 2013 and 2014. Plants were collected from different sampling sites, identified, preserved and deposited in Herbarium of Hazara University, Mansehra. A total of 127 plants species including 59 common and 68 different were found in 13 stands of reserved forest. The different species were only confined with this forest whereas common plant species were distributed in both forests. The dominant family was Asteraceae (13 species, 10.7%) followed by Labiateae (10 species, 7.75%), Poaceae and Rosaceae (8 species, 6.2%) each, Polygonaceae and Pteridaceae by (5 species, 3.87%) each. Angiosperms were represented by 118 (92.91%), plant species, Pteridophytes 5(3.93%) species and Gymnosperms 4 (3.14%) species were recorded in reserved forest. Only single species of climber was documented. The number of herbs, shrubs and trees species recorded were 73.64%, 13.17% and 10.07% respectively. A total of 103 plant species of 55 families including 61 common in both forest types and 42 species different to guzara Forest. These plant species were recorded from 22 sampling stands. Angiosperms by (92.3%) plant species, Gymnosperms (2.88%) and Pteridophytes (4.8%) were recorded. The dominant family was Poaceae by 11 plant species followed by Asteraceae and Rosaceae each represented by 10 species and Pteridaceae by 5 plant species. Habit wise 69.23% were herbs, 14.42% shrubs and 16.34% species of tree were reported. This study will assist ecologists, botanists, taxonomist, conservationists and policy makers to mend, and manage the current vegetation status and sustainability for upcoming generations. The present investigation will also serves as base line for future researches on the Himalaya regions.  相似文献   

13.
Antibiotic-resistant Escherichia coli strains including extended-spectrum β-lactamase (ESBL) isolates are globally widespread in medical, food, and environmental sources. Some of these strains are considered the most pathogenic bacteria in humans. The present work examined the predominance of antibiotic resistance in E. coli strains in wound infections comparing with E. coli strains isolated from a raw milk as a potential source of those strains. The wound infections included abdomen, anus, arm, back, buttock, chest, foot, hand, head, leg, lung, mouth, neck, penis, thigh, toe, and vagina infections. In total, 161 and 153 isolates identified as E. coli were obtained from wound infections and raw milk, respectively. A Vitek 2 system innovated by bioMérieux, France was applied to perform the identification and susceptibility tests. The E. coli isolates that have ability to produce ESBL were detected by an ESBL panel and NO45 card (bioMérieux). Over half of the E. coli were from abdomen, back, and buttock wound infections. More than 50%of the E. coli isolates obtained from wound infections were resistant to cefazolin, ampicillin, cefuroxime, ciprofloxacin, mezlocillin, moxifloxacin, piperacillin, and tetracycline; 70% of the isolates from wound infections and 0% of the isolates from raw milk were E. coli isolates produced ESBL. The data showed that the strains resistance to multi-antibiotic and produced ESBL are more widespread among wound infections than in raw milk.  相似文献   

14.
Hexamerins are hemolymph-proteins, which are mainly considered as storage proteins for non-feeding stages, and also undertake other roles during insect development and growth, however the characterization of hexamerin proteins in Spodoptera exigua is less understood. In this study five new hexamerin genes were identified and a total seven hexamerin genes were reported in S. exigua. These hexamerins contain the typical domains of hemocyanin at the N-terminal, C-terminal and in the middle of their protein sequences. These genes are mainly expressed in fat body, and the signal peptide sequences at their N-terminal of protein sequences can drive the expressed protein to excrete into hemolymph after synthesis. The phylogenetic analysis and amine acid composition revealed S. exigua express five different types of hexamerins: 1) Storage protein rich in methionine residue (MRSP), 2) Storage protein moderately rich in methionine (MMRSP), 3) Hexamerin with high composition of aromatic amino acids (Arylphorin), 4) Arylphorin-like hexamerin, and 5) Riboflavin-binding hexamerin (RbH). The phylogenetic pattern combined with the comparison of conserved histidine residues in copper binding sites of hexamerins revealed basal position of RbH and the evolutionary pathway in lepidopteran hexamerins. Finally, the induction expression of hexamerins by insecticide, lambda-cyhalothrin, were analyzed, results showed that lambda-cyhalothrin exposure may down-regulate their expression. This study increased the gene number of hexamerin to seven, and reported their expression and structural characterizations, the finding will facilitate the understand of hexamerin in other insects.  相似文献   

15.
Defects in the development, maintenance or expansion of β-cell mass can result in impaired glucose metabolism and diabetes. N6-methyladenosine affects mRNA stability and translation efficiency, and impacts cell differentiation and stress response. To determine if there is a role for m6A in β-cells, we investigated the effect of Mettl14, a key component of the m6A methyltransferase complex, on β-cell survival and function using rat insulin-2 promoter-Cre-mediated deletion of Mettl14 mouse line (βKO). We found that βKO mice with normal chow exhibited glucose intolerance, lower levels of glucose-stimulated insulin secretion, increased β-cell death and decreased β-cell mass. In addition, HFD-fed βKO mice developed glucose intolerance, decreased β-cell mass and proliferation, exhibited lower body weight, increased adipose tissue mass, and enhanced insulin sensitivity due to enhanced AKT signaling and decreased gluconeogenesis in the liver. HFD-fed βKO mice also showed a decrease in de novo lipogenesis, and an increase in lipolysis in the liver. RNA sequencing in islets revealed that Mettl14 deficiency in β-cells altered mRNA expression levels of some genes related to cell death and inflammation. Together, we showed that Mettl14 in β-cells plays a key role in β-cell survival, insulin secretion and glucose homeostasis.  相似文献   

16.
17.
A highly sensitive and ultra-fast high performance liquid chromatography- tandem mass spectrometry (LC–MS/MS) assay is developed and validated for the quantification of Lenalidomide in human plasma. Lenalidomide is extracted from human plasma by Liquid- Liquid Extraction by Ethyl Acetate and analyzed using a reversed phase isocratic elution on a XTerra RP18, (4.6 × 50 mM, 5 µm) column. A 0.1% Formic acid: Methanol (10:90% v/v), is used as mobile phase and detection was performed by Triple quadrupole mass spectrometry LC-MS/MS using electrospray ionization in positive mode. Fluconazole is used as the internal standard. The lower limit of quantification is 9.999 ng/mL for Lenalidomide. The calibration curves are consistently accurate and precise over the concentration range of 9.999 to 1010.011 ng/mL in plasma for Lenalidomide. This novel LC–MS/MS method competes with all the regulatory requirements and shows satisfactory accuracy and precision and is sufficiently sensitive for the performance of pharmacokinetic and bioequivalence studies in humans.  相似文献   

18.
Schistosomiasis is widely distributed along the Senegal River Basin (SRB), affecting both the human population and their livestock. Damming of the Senegal River for irrigation purposes in the 1980s induced ecological changes that resulted in a large outbreak of Schistosoma mansoni, followed a few years later by an increase and spread of Schistosoma haematobium infections. The presence of hybrid crosses between the human and cattle schistosomes, S. haematobium and Schistosoma bovis, respectively, is adding complexity to the disease epidemiology in this area, and questions the strength of the species boundary between these two species. This study aimed to investigate the epidemiology of S. haematobium, S. bovis and their hybrids along the Senegal River basin using both microsatellite genetic markers and analysis of mitochondrial and nuclear DNA markers. Human schistosome populations with a S. haematobium cox1 mtDNA profile and those with a S. bovis cox1 mtDNA profile (the so-called hybrids) appear to belong to a single randomly mating population, strongly differentiated from the pure S. bovis found in cattle. These results suggest that, in northern Senegal, a strong species boundary persists between human and cattle schistosome species and there is no prolific admixing of the populations. In addition, we found that in the SRB S. haematobium was spatially more differentiated in comparison to S. mansoni. This may be related either to the presence and susceptibility of the intermediate snail hosts, or to the colonisation history of the parasite.  相似文献   

19.
Human semen quality has declined worldwide in the last 40 years, by some accounts as much as 50–60%, causing serious concerns and implications for human fertility. Even though it has been shown to be a worldwide problem, this decrease is more pronounced in developed and industrialized countries, pointing to changes in modifiable lifestyle factors (e.g. unhealthy diets, lifestyles, and pollution) as the main causes. Studies investigating the relation between diet and semen quality can be classified into three groups; studies assessing the association between semen quality and 1) nutrients, dietary supplements and antioxidants, 2) food, and 3) dietary patterns. The present narrative review provides a wide-ranging vision of the positive associations and effects of diet on sperm quality. Although the picture of the relationship between diet and sperm quality and fertility is far from complete, a number of broad conclusions have emerged. First, increased intake of selenium and zinc, omega-3 (ω-3) fatty acids, CoenzymeQ10 (CoQ10) and carnitine supplements have been positively related to sperm quality. In terms of food groups, vegetables, fruits, nuts and whole cereals, all rich in fiber and antioxidants, and fish, seafood, shellfish, poultry, and low-fat dairy products have been positively associated with sperm quality. Finally, adherence to healthy dietary patterns is positively associated with sperm concentration and sperm motility.  相似文献   

20.
To investigate whether autophagy and subcellular changes are involved in the corpus luteum after heat exposure, a total of 30 early pregnant mice were divided equally into heat stress (HS) and non-HS (NHS) groups (n = 15). Mice in the HS group were exposed to 40.5 ± 0.2 ℃ for 7 consecutive days. Ovaries were collected for immunohistochemistry (IHC), western blot (WB) analysis and transmission electron microscopy (TEM). Serum was collected to determine progesterone by RIA and uteri were collected to count the implantation sites. Results showed that heat exposure increased rectal temperature, decreased body weight and number of implantation sites. WB analysis revealed that ovarian expression of LC3B and Atg7 was up-regulated, while p62 was down-regulated in the HS group. IHC results demonstrated that ovarian staining intensity of LC3B was more intense in the HS group than that of the NHS group. LC3B was mainly localized in the granulosa cells, oocytes and luteal steroidogenic cells of the HS group. TEM results revealed double-layered separated membranes indicative of autophagosomes in the luteal steroidogenic cells of the HS group. Moreover, TEM showed that the mitochondrial cristae became dearth, structure-less, swollen after HS. Additionally, the nucleus expanded and accumulation of lipid droplets increased after HS. Results also showed that heat exposure decreased serum progesterone level and ovarian P450scc expression. These results indicate that HS enhanced autophagy and altered the subcellular structure of luteal steroidogenic cells, which may contribute to interfering with the maintenance of luteal function in early pregnant mice.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号