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1.
Insect Sci ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783625

RESUMO

Vitellogenin receptor (VgR) plays a crucial role in oogenesis by mediating endocytosis of vitellogenin and a portion of the yolk proteins in many insect species. However, the function of VgR in minute parasitoid wasps is largely unknown. Here, we applied Trichogramma dendrolimi, a minute egg parasitoid, as a study model to investigate the function of VgR in parasitoids. We developed RNA interference (RNAi) methods based on microinjection of prepupae in T. dendrolimi. RNAi employs nanomaterial branched amphipathic peptide capsules (BAPC) as a carrier for double-stranded RNA (dsRNA), significantly enhancing delivery efficiency. Also, artificial hosts without medium were used to culture the injected prepupae in vitro. Utilizing these methods, we found that ovarian growth was disrupted after knockdown of TdVgR, as manifested by the suppressed development of the ovariole and the inhibition of nurse cell internalization by oocytes. Also, the initial mature egg load in the ovary was significantly reduced. Notably, the parasitic capacity of the female adult with ovarian dysplasia was significantly decreased, possibly resulting from the low availability of mature eggs. Moreover, ovarian dysplasia in T. dendrolimi caused by VgR deficiency are conserved despite feeding on different hosts. The results confirmed a critical role of TdVgR in the reproductive ability of T. dendrolimi and provided a reference for gene functional studies in minute insects.

2.
J Econ Entomol ; 117(1): 93-101, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38124393

RESUMO

In this study, 5 species of Trichogramma Westwood were evaluated for the biological control of Spodoptera frugiperda (JE Smith), concerning the physical characteristics of female Trichogramma. The results showed that Trichogramma chilonis Ishii, Trichogramma dendrolimi Matsumura, and Trichogramma ostriniae Pang et Chen exhibited high parasitism rates, emergence rates, and offspring numbers, with the highest values observed for T. ostriniae. The ovipositor length of Trichogramma japonicum Ashmead and T. dendrolimi were longer than those of other species, and the hind tibia length was the shortest in Trichogramma cacoeciae Marchal. We further evaluated relationships between the parasitism ability of Trichogramma and various morphological indexes based on Spearman's rank correlation coefficients. A positive correlation was found between the parasitism rate and hind tibia length of T. cacoeciae. In T. dendrolimi, the parasitism rate was negatively correlated with ovipositor width and positively correlated with the length-width ratio of the ovipositor. A significant positive correlation was observed between the proportion of female offspring and the mother's ovipositor length in T. japonicum. However, there were no significant correlations between morphological indexes and indexes of parasitism in T. ostriniae. Overall, the parasitic abilities of T. chilonis on S. frugiperda eggs were significantly correlated with the morphology of the female ovipositors.


Assuntos
Himenópteros , Lepidópteros , Mariposas , Vespas , Feminino , Animais , Spodoptera/parasitologia , Mariposas/parasitologia , Controle Biológico de Vetores/métodos
3.
J Vis Exp ; (200)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37870359

RESUMO

Parasitoid wasps are a diverse group of hymenopteran insects that serve as invaluable resources for pest biocontrol. To ensure successful parasitism, parasitoid wasps inject venom into their hosts to suppress their hosts' immunity, modulate hosts' development, metabolism, and even behavior. With over 600,000 estimated species, the diversity of parasitoid wasps surpasses that of other venomous animals, such as snakes, cone snails, and spiders. Parasitoid wasp venom is an underexplored source of bioactive molecules with potential applications in pest control and medicine. However, collecting parasitoid venom is challenging due to the inability to use direct or electrical stimulation and the difficulty in dissection because of their small size. Trichogramma is a genus of tiny (~0.5 mm) egg parasitoid wasps that are widely used for the biological control of lepidopteran pests in both agriculture and forests. Here, we report a method for extracting venom from T. dendrolimi using artificial hosts. These artificial hosts are created with polyethylene film and amino acid solutions and then inoculated with Trichogramma wasps for parasitism. The venom was subsequently collected and concentrated. This method enables the extraction of large amounts of Trichogramma venom while avoiding contamination from other tissues caused by dissection, a common issue in venom reservoir dissection protocols. This innovative approach facilitates the study of Trichogramma venom, paving the way for new research and potential applications.


Assuntos
Vespas , Animais , Vespas/fisiologia , Peçonhas
4.
Int J Surg ; 109(10): 3061-3069, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37526126

RESUMO

BACKGROUND: APROPOS was a multicentre, randomized, blinded trial focus on investigating the perineal nerve block versus the periprostatic block in pain control for men undergoing a transperineal prostate biopsy. In the analysis reported here, the authors aimed to evaluate the association of biopsy core count and location with pain outcomes in patients undergoing a transperineal prostate biopsy under local anesthesia. METHODS: APROPOS was performed at six medical centers in China. Patients with suspected prostate cancer were randomized to receive either a perineal nerve block or a periprostatic block (1:1), followed by a transperineal prostate biopsy. The secondary analysis outcomes were the worst pain experienced during the prostate biopsy and postbiopsy pain at 1,6, and 24 h. RESULTS: Between 12 August 2020 and 20 July 2022, a total of 192 patients were randomized in the original trial, and 188 were involved in this analysis, with 94 patients per group. Participants had a median (IQR) age of 68 (63-72) and a median (IQR) prostate volume of 42.51 (30.04-62.84). The patient population had a median (IQR) number of biopsy cores of 15 (12-17.50), and 26.06% of patients had a biopsy cores count of more than 15. After adjusting the baseline characteristics, the number of biopsy cores was associated with the worst pain during the biopsy procedure in both the perineal nerve block group ( ß 0.19, 95% CI: 0.12-0.26, P <0.001) and the periprostatic block group ( ß 0.16, 95% CI: 0.07-0.24, P <0.001). A similar association was also evident for the postbiopsy pain at 1, 6, and 24 h. A lesser degree of pain in both groups at any time (r range -0.57 to -0.01 for both groups) was associated with biopsy cores from the peripheral zone of the middle gland, while other locations were associated with a higher degree of pain. In addition, the location of the biopsy core had less of an effect on pain during the biopsy (r range -0.01-0.25 for both groups) than it did on postbiopsy pain (r range -0.57-0.60 for both groups). CONCLUSIONS: In this secondary analysis of a randomized trial, biopsy core count and location were associated with pain in patients undergoing a transperineal prostate biopsy under local anesthesia. These results may be helpful for making clinical decisions about the anesthetic approach for scheduled transperineal prostate biopsies.


Assuntos
Dor Processual , Neoplasias da Próstata , Masculino , Humanos , Próstata/patologia , Anestesia Local/efeitos adversos , Anestesia Local/métodos , Biópsia/efeitos adversos , Dor/etiologia , Dor/prevenção & controle , Dor Processual/epidemiologia
5.
Insects ; 13(6)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35735886

RESUMO

Despite its substantial costs, sexual reproduction dominates in animals. One popular explanation for the paradox of sex is that asexual reproduction is more likely to accumulate deleterious mutations than sexual reproduction. To test this hypothesis, we compared the mitogenomes of two asexual wasp strains, Trichogramma cacoeciae and T. pretiosum, to their sexual relatives. These two asexual strains represent two different transition mechanisms in Trichogramma from sexual to asexual reproduction. Asexual T. pretiosum is induced by Wolbachia, while T. cacoeciae presumably originated from interspecific hybridization. We sequenced and assembled complete mitochondrial genomes of asexual T. cacoeciae and T. pretiosum. Compared to four sexual relatives, we found no evidence of higher mutation accumulation in asexual Trichogramma mitogenomes than in their sexual relatives. We also did not detect any relaxed selection in asexual Trichogramma mitogenomes. In contrast, the intensified selection was detected in Nad1 and Nad4 of the asexual T. pretiosum mitogenome, suggesting more purifying selection. In summary, no higher mitochondrial mutation accumulation was detected in these two asexual Trichogramma strains. This study provides a basis for further investigating mitochondrial evolution and asexual reproduction in Trichogramma.

6.
J Econ Entomol ; 115(4): 1095-1101, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35746894

RESUMO

Parasitoid wasps are invaluable agents in pest biological control. Early detection and identification of parasitoid immatures are vital in characterizing parasitoid-host interactions and for evaluating parasitism rates accurately in the field. Trichogramma is the most widely used parasitoid wasp, and several studies have been performed for its molecular identification. However, those studies were mainly focused on Trichogramma adults and rarely on immatures. Here, we report a method to detect and identify Trichogramma larvae in their host eggs. We designed a pair of Trichogramma-specific primers that amplified Trichogramma mtCOI sequences from Corcyra cephalonica (Stainton) eggs parasitized by any of eight Trichogramma species tested but not from nonparasitized eggs of four lepidopteran hosts. This PCR method reliably detected Trichogramma immatures in parasitized eggs as early as 1 h after parasitism. We further developed an RFLP (restriction fragment length polymorphism) assay using restriction enzymes SspI and VspI to differentiate eight Trichogramma species at their immature stage. Overall, we developed a sensitive and reliable PCR-RFLP method to detect and identify immature-stage Trichogramma in their lepidopteran hosts. This method shows promise for conveniently identifying Trichogramma in insectaries and accurately evaluating parasitism rates in the field.


Assuntos
Himenópteros , Lepidópteros , Mariposas , Vespas , Animais , Larva/genética , Mariposas/genética , Controle Biológico de Vetores/métodos , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Vespas/genética
7.
Chem Asian J ; 17(1): e202101135, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34729930

RESUMO

Functional supramolecular gel materials have potential applications in sensors, optical switches, artificial antennae, drug delivery and so on. In this paper, quinoline-cored poly(aryl ether) dendritic organogelators were designed, synthesized and fully characterized. The gelation behaviour of the dendritic organogelator was tested in organic solvents, mixed solvents and ionic liquids. The dendron Q-G1 was found to be an efficient and versatile organogelator toward various apolar and polar organic solvents with the critical gelation concentrations (CGCs) approaching 1.2×10-2  mol/L, indicating one dendritic organogelator could immobilize 1.2×103 solvent molecules in the organogel network. Interestingly, these dendrons exhibited excellent gel formation in ionic liquids. Notably, these dendritic organogels were found to display multiple stimuli-responsive properties toward external stimuli including heat, ultrasound and shear stress, with a reversible sol-gel phase transition. In addition, the dendritic organogel could effectively adsorb heavy metals and organic dyes. The removal rate of Pb2+ was up to 20% and the adsorption rate for Rhodamine B was as high as 89%.

8.
BMC Genomics ; 22(1): 569, 2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34301178

RESUMO

BACKGROUND: The two-spotted spider mite, Tetranychus urticae, is a major agricultural pest with a cosmopolitan distribution, and its polyphagous habits provide a model for investigating herbivore-plant interactions. There are two body color forms of T. urticae with a different host preference. Comparative genomics and transcriptomics are used here to investigate differences in responses of the forms to host plants at the molecular level. Biological responses of the two forms sourced from multiple populations are also presented. RESULTS: We carried out principal component analysis of transcription changes in three red and three green T. urticae populations feeding on their original host (common bean), and three hosts to which they were transferred: cotton, cucumber and eggplant. There were differences among the forms in gene expression regardless of their host plant. In addition, different changes in gene expression were evident in the two forms when responding to the same host transfer. We further compared biological performance among populations of the two forms after feeding on each of the four hosts. Fecundity of 2-day-old adult females showed a consistent difference between the forms after feeding on bean. We produced a 90.1-Mb genome of the red form of T. urticae with scaffold N50 of 12.78 Mb. Transcriptional profiles of genes associated with saliva, digestion and detoxification showed form-dependent responses to the same host and these genes also showed host-specific expression effects. CONCLUSIONS: Our research revealed that forms of T. urticae differ in host-determined transcription responses and that there is form-dependent plasticity in the transcriptomic responses. These differences may facilitate the extreme polyphagy shown by spider mites, although fitness differences on hosts are also influenced by population differences unrelated to color form.


Assuntos
Tetranychidae , Animais , Feminino , Perfilação da Expressão Gênica , Genômica , Plantas , Tetranychidae/genética , Transcriptoma
9.
Biomaterials ; 276: 121007, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34237505

RESUMO

The outbreak of infectious diseases such as COVID-19 causes an urgent need for abundant personal protective equipment (PPE) which leads to a huge shortage of raw materials. Additionally, the inappropriate disposal and sterilization of PPE may result in a high risk of cross-contamination. Therefore, the exploration of antimicrobial materials possessing both microbe interception and self-decontamination effects to develop reusable and easy-to-sterilize PPE is of great importance. Herein, an aggregation-induced emission (AIE)-active luminogen-loaded nanofibrous membrane (TTVB@NM) sharing sunlight-triggered photodynamic/photothermal anti-pathogen functions are prepared using the electrospinning technique. Thanks to its porous nanostructure, TTVB@NM shows excellent interception effects toward ultrafine particles and pathogenic aerosols. Benefiting from the superior photophysical properties of the AIE-active dopants, TTVB@NM exhibits integrated properties of wide absorption in visible light range, efficient ROS generation, and moderate photothermal conversion performance. A series of antimicrobial evaluations reveal that TTVB@NM could effectively inactivate pathogenic aerosols containing bacteria (inhibition rate: >99%), fungi (~88%), and viruses (>99%) within only 10 min sunlight irradiation. This study represents a new strategy to construct reusable and easy-to-sterilize hybrid materials for potential bioprotective applications.


Assuntos
Anti-Infecciosos , COVID-19 , Nanofibras , Anti-Infecciosos/farmacologia , Humanos , SARS-CoV-2 , Luz Solar
10.
Soft Matter ; 17(25): 6081-6087, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34109344

RESUMO

Chain entanglement behaviors were studied by 1H Hahn echo nuclear magnetic resonance (NMR) and 1H double-quantum (DQ) NMR experiments. Poly(ethylene oxide) (PEO) was chosen to investigate the chain entanglement behaviors. The 1H Hahn echo NMR results demonstrate that the critical molecular weight of PEO is approximately 6 kg mol-1. Above this critical molecular weight, chain entanglements start to occur in the melts resulting in anisotropic motions of polymer chain. The 1H DQ NMR observations establish that PEO melts with molecular weights above the critical value exhibit dynamical entanglements. The entangled networks, formed by PEO with a molecular weight of 480 kg mol-1 (PEO480), present slow mobility and rather homogeneously distributed chain entanglements, while the entangled networks, formed by PEO with a molecular weight of 255 kg mol-1 (PEO255), present fast mobility and obvious dynamic heterogeneity in the distribution of chain entanglement. Short chain PEOs like that with a molecular weight of 2 kg mol-1 are demonstrated to function like solvents when being added in an appropriate concentration to PEO480, and the dilution effect increases the chain mobility of PEO480. Moreover, properly diluted PEO480 networks exhibit dynamic heterogeneity similar to that observed in PEO255.

11.
Artigo em Inglês | MEDLINE | ID: mdl-33166853

RESUMO

Insects perceive dangerous or attractive chemicals in the environment (such as the presence of predators, food or mates) through their olfaction and gustation. This leads to host searching, mate finding and other behaviors that are critical for insect survival. These vital activities are mediated by many chemosensory receptor proteins, including odorant receptors (ORs), gustatory receptors (GRs) and ionotropic receptors (IRs). Trichogramma japonicum Ashmead (Hymenoptera: Trichogrammatidae) is a commonly used egg parasitoid for controlling lepidopteran pests in rice fields. To reveal the roles of its olfactory and gustatory systems in biological control, we systematically analyzed major chemosensory receptor genes from T. japonicum. Through transcriptomic analyses of male and female heads, we found that the differentially expressed genes (DEGs) were mainly related to chemosensory functions, and there were more chemosensory-related genes expressed in female heads than male heads, which may be related to the need for females to search for their hosts or sense male pheromone. Furthermore, we identified 66 chemosensory receptor genes, including 51 ORs, seven IRs and eight GRs, that were most closely relate to those of other hymenopteran species according to the results of both Blast best-hit and phylogenetic analyses. The tissue expression profile showed that 65 of the 66 chemosensory receptors were highly expressed in the heads, suggesting their putative roles in olfaction and gustation. In addition, the sex-specific expression patterns suggested their potential functions in host-seeking or mate sensing behaviors. This study may provide base for further understanding the olfactory and gustatory systems of T. japonicum and increasing its efficiency in pest control in the future.


Assuntos
Himenópteros/genética , Transcriptoma , Animais , Feminino , Perfilação da Expressão Gênica , Genes de Insetos , Proteínas de Insetos/genética , Masculino , Filogenia , Receptores de Superfície Celular/genética , Receptores Odorantes/genética
12.
ACS Appl Mater Interfaces ; 12(43): 49050-49060, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33064940

RESUMO

A robust hybrid ion gel is fabricated utilizing the combined strategies of double-network (DN), composite, and high-functionality cross-linkers. The charged poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPS) constructs the DN skeleton, with graphene oxide (GO) and N,N'-methylenebisacrylamide (MBA) being the cross-linkers for the first and second networks, respectively. The ionic liquid, either 1-ethyl-3-methylimidazolium dicyanamide ([EMIm][DCA]) or 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIm][BF4]), is locked in the network to offer the high conductivity. Compared to the DN PAMPS ion gel without nanoparticles and the hybrid DN ion gel with unconnected silica nanoparticles, the present ion gel exhibits a significantly higher tensile strength (3.2 ± 0.1 MPa) and an excellent compressive strength (26 ± 1 MPa). The [EMIm][DCA] ion gel has a high conductivity close to that of its neat ionic liquids. The conductivity of the gel is sensitive to deformation and temperature, which leads to potential applications in sensing body movements, pulse, and temperature change.

13.
Front Physiol ; 11: 9, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32038312

RESUMO

Parasitoid wasps inject venom containing complex bioactive compounds to regulate the immune response and development of host arthropods and sometime paralyze host arthropods. Although extensive studies have been conducted on the identification of venom proteins in larval parasitoids, relatively few studies have examined the pupal parasitoids. In our current study, a combination of transcriptomic and proteomic methods was used to identify 64 putative venom proteins from Pachycrepoideus vindemmiae, an ectoparasitoid of Drosophila. Expression analysis revealed that 20 tested venom proteins have 419-fold higher mean expression in the venom apparatus than in other wasp tissues, indicating their specialization to venom. Comparisons of venom proteins from P. vindemmiae and other five species spanning three parasitoid families detected a core set of "ancient" orthologs in Pteromalidae. Thirty-five venom proteins of P. vindemmiae were assigned to the orthologous groups by reciprocal best matches with venoms of other pteromalids, while the remaining 29 were not. Of the 35 categories, twenty-seven have orthologous relationships with Nasonia vitripennis venom proteins and 25 with venoms of Pteromalus puparum. More distant relationships detected that five and two venom proteins of P. vindemmiae are orthologous with venoms of two Figitidae parasitoids and a Braconidae representative, respectively. Moreover, twenty-two venoms unique to P. vindemmiae were also detected, indicating considerable interspecific variation of venom proteins in parasitoids. Phylogenetic reconstruction based on a set of single-copy genes clustered P. vindemmiae with P. puparum, N. vitripennis, and other members of the family Pteromalidae. These findings provide strong evidence that P. vindemmiae venom proteins are well positioned for future functional and evolutionary studies.

14.
Polymers (Basel) ; 11(10)2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31546998

RESUMO

The linear and nonlinear rheology of associative colloidal polymer assemblies with metallo-supramolecular interactions is herein studied. Polystyrene-b-poly(tert-butylacrylate) with a terpyridine ligand at the end of the acrylate block is self-assembled into micelles in ethanol, a selective solvent for the latter block, and supramolecularly connected by complexation to divalent metal ions. The dependence of the system elasticity on polymer concentration can be semi-quantitatively understood by a geometrical packing model. For strongly associated (Ni2+, Fe2+) and sufficiently concentrated systems (15 w/v%), any given ligand end-group has a virtually 100% probability of being located in an overlapping hairy region between two micelles. By assuming a 50% probability of intermicellar crosslinks being formed, an excellent prediction of the plateau modulus was achieved and compared with the experimental results. For strongly associated but somewhat more dilute systems (12 w/v%) that still have significant overlap between hairy regions, the experimental modulus was lower than the predicted value, as the effective number of crosslinkers was further reduced along with possible density heterogeneities. The reversible destruction of the network by shear forces can be observed from the strain dependence of the storage and loss moduli. The storage moduli of the Ni2+ and Zn2+ systems at a lower concentration (12 w/v%) showed a rarely observed feature (i.e., a peak at the transition from linear to nonlinear regime). This peak disappeared at a higher concentration (15 w/v%). This behavior can be rationalized based on concentration-dependent network stretchability.

15.
Polymers (Basel) ; 11(5)2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31052491

RESUMO

The thermoreversible sol-gel transition for an ionic liquid (IL) solution of isotactic-rich poly (N-isopropylacrylamides) (PNIPAMs) is investigated by rheological technique. The meso-diad content of PNIPAMs ranges between 47% and 79%, and molecular weight (Mn) is ~35,000 and ~70,000 g/mol for two series of samples. PNIPAMs are soluble in 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl) imide ([BMIM][TFSI]) at high temperatures but undergo a gelation with decreasing temperatures. The transition temperature determined from G'-G" crossover increases with isotacticity, consistent with the previous cloud-point result at the same scanning rate, indicating imide groups along the same side of backbones are prone to be aggregated for formation of a gel. The transition point based on Winter-Chambon criterion is on average higher than that of the G'-G" crossover method and is insensitive to tacticity and molecular weight, since it correlates with percolation of globules rather than the further formation of elastic network (G' > G"). For the first time, the phase diagram composed of both G'-G" crossover points for gelation and cloud points is established in PNIPAM/IL mixtures. For low-Mn PNIPAMs, the crossover-point line intersects the cloud-point line. Hence, from solution to opaque gel, the sample will experience two different transitional phases, either clear gel or opaque sol. A clear gel is formed due to partial phase separation of isotactic segments that could act as junctions of network. However, when the partial phase separation is not faster than the formation of globules, an opaque sol will be formed. For high-Mn PNIPAMs, crossover points are below cloud points at all concentrations, so their gelation only follows the opaque sol route. Such phase diagram is attributed to the poorer solubility of high-Mn polymers for entropic reasons. The phase diagram composed of Winter-Chambon melting points, crossover points for melting, and clear points is similar with the gelation phase diagram, confirming the mechanism above.

16.
Polymers (Basel) ; 11(5)2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31091730

RESUMO

An anomalous plasticizing effect was observed in polymer/ionic liquid (IL) solutions by applying broad range of rheological techniques. Poly(ethylene oxide)(PEO)/IL solutions exhibit stronger dynamic temperature dependence than pure PEO, which is in conflict with the knowledge that lower-Tg solvent increases the fractional free volume. For poly(methy methacrylate)(PMMA)/IL solutions, the subtle anomaly was detected from the fact that the effective glass transition temperature Tg,eff of PMMA in IL is higher than the prediction of the self-concentration model, while in conventional polymer solutions, Tg,eff follows the original Fox equation. Observations in both solutions reveal retarded segmental dynamics, consistent with a recent simulation result (Macromolecules, 2018, 51, 5336) that polymer chains wrap the IL cations by hydrogen bonding interactions and the segmental unwrapping delays their relaxation. Start-up shear and nonlinear stress relaxation tests of polymer/IL solutions follow a universal nonlinear rheological behavior as polymer melts and solutions, indicating that the segment-cation interaction is not strong enough to influence the nonlinear chain orientation and stretch. The present work may arouse the further theoretical, experimental, and simulation interests in interpreting the effect of complex polymer-IL interaction on the dynamics of polymer/IL solutions.

17.
Int J Ophthalmol ; 12(4): 542-548, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31024804

RESUMO

AIM: To determine the progression of parameters from optical coherence tomography (OCT) in chronic elevated intraocular pressure (IOP) monkeys. METHODS: A chronic elevated IOP model of rhesus monkeys was induced by laser photocoagulation. Representative OCT parameters, including the average and four-quadrant retinal nerve fiber layer (RNFL) thickness, and parameters from optic nerve head (ONH) analysis were collected before and after laser treatments biweekly for up to 28wk. The performance of each parameter for early progression detection was analyzed. The progressive trends toward elevated IOP were analyzed using a linear mixed-effects model. RESULTS: There were 10 successfully maintained high IOP eyes in 7 monkeys. The follow-up time was 24±5.37wk. With cumulative IOP elevation, the cup area, rim area and C/D area ratio were statistically significantly changed as early as 2wk after elevated IOP induction (P<0.05). The quadrant RNFL thickness changed at 6wk after high IOP induction, and the superior and inferior RNFL thicknesses exhibited more obvious reductions than other quadrants. The average RNFL thickness was the last one to show a significant decrease at 8wk. CONCLUSION: The parameters of ONH are most sensitive to elevated IOP in a primate glaucomatous model. These findings suggest that we should focus on those parameters instead of RNFL thickness in patients with elevated IOP, as they might present with earlier glaucomatous changes.

18.
Carbohydr Polym ; 199: 58-67, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30143165

RESUMO

Here, we report on the effect of functional copolymer poly(N-isopropylacrylamide-co-4-vinyl-phenylboronic acid) (NIBA) on the rheology and network structure formed by sodium alginate (SA) through linear and nonlinear viscoelasticity measurements. The hydrogel moduli at pH 3 increased with increasing NIBA addition, while the yield point decreased. Furthermore, these hydrogels showed strain-softening behavior, weak G″-overshoot marking the onset of nonlinearity, and good self-healing properties after large deformation. The zero-strain nonlinearity parameter (Q0) was found to be more sensitive to NIBA-addition than the linear viscoelastic properties. The blends showed a clear peak in the startup test except for SA alone and the peak intensity increased with increasing NIBA-concentration. Finally, based on all data, gelation mechanism and interaction of SA and NIBA will be clarified.

19.
Polymers (Basel) ; 10(9)2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30960898

RESUMO

We report on the viscoelastic properties of linear, monocyclic, and multicyclic polystyrenes with the same low molecular weight. All polymers investigated were found to exhibit unentangled dynamics. For monocyclic polymers without inner loops, a cyclic-Rouse model complemented by the contribution of unlinked chains (whose fraction was determined experimentally) captured the observed rheological response. On the other hand, multicyclic polymers with inner loops were shown to follow a hierarchical cyclic-Rouse relaxation with the outer loops relaxing first, followed by the inner loop relaxation. The influence of unlinked linear chains was less significant in multicyclic polymers with inner loops. The isofrictional zero-shear viscosity decreased with increasing number of constrained segments on the coupling sites, which was attributed to the decreasing loop size and the dilution effect due to the hierarchical relaxation.

20.
Toxins (Basel) ; 9(4)2017 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-28417942

RESUMO

Many species of endoparasitoid wasps provide biological control services in agroecosystems. Although there is a great deal of information on the ecology and physiology of host/parasitoid interactions, relatively little is known about the protein composition of venom and how specific venom proteins influence physiological systems within host insects. This is a crucial gap in our knowledge because venom proteins act in modulating host physiology in ways that favor parasitoid development. Here, we identified 37 possible venom proteins from the polydnavirus-carrying endoparasitoid Cotesia chilonis by combining transcriptomic and proteomic analyses. The most abundant proteins were hydrolases, such as proteases, peptidases, esterases, glycosyl hydrolase, and endonucleases. Some components are classical parasitoid venom proteins with known functions, including extracellular superoxide dismutase 3, serine protease inhibitor and calreticulin. The venom contains novel proteins, not recorded from any other parasitoid species, including tolloid-like proteins, chitooligosaccharidolytic ß-N-acetylglucosaminidase, FK506-binding protein 14, corticotropin-releasing factor-binding protein and vascular endothelial growth factor receptor 2. These new data generate hypotheses and provide a platform for functional analysis of venom components.


Assuntos
Proteínas de Insetos/genética , Venenos de Vespas/genética , Animais , Feminino , Filogenia , Proteômica , RNA Mensageiro/metabolismo , Transcriptoma , Vespas/genética
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