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81.
Nanoparticles (NPs) may help treat multidrug-resistant Staphylococcus aureus (MDR). This study prepared and evaluated chitosan/alginate-encapsulated Echinacea angustifolia extract against MDR strains. Evaluating synthesized NPs with SEM, DLS, and FT-IR. Congo red agar and colorimetric plate techniques examined isolate biofilm formation. NP antibacterial power was assessed using well diffusion. Real-time PCR assessed biofilm-forming genes. MTT assessed the synthesized NPs′ toxicity. According to DLS measurements, spherical E. angustifolia NPs had a diameter of 335.3±1.43 nm. The PDI was 0.681, and the entrapment effectiveness (EE%) of the E. angustifolia extract reached 83.45 %. Synthesized NPs were most antimicrobial. S. aureus resistant to several treatments was 80 percent of 100 clinical samples. Biofilm production was linked to MDR in all strains. The ALG/CS-encapsulated extract had a 4 to 32-fold lower MIC than the free extract, which had no bactericidal action. They also significantly decreased the expression of genes involved in biofilm formation. E. angustifolia-encapsulated ALG/CS decreased IcaD, IcaA, and IcaC gene expression in all MDR strains (***p<0.001). Free extract, free NPs, and E. angustifolia-NPs had 57.5 %, 85.5 %, and 90.0 % cell viability at 256 μg/ml. These discoveries could assist generate stable plant extracts by releasing natural-derived substances under controlled conditions.  相似文献   
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Indomethacin-treated bovine iris-ciliary body microsomes (IBIM) have been studied for their ability to convert PG endoperoxides into either thromboxane-A2 (TxA2)-like or prostacyclin (PGI2)-like activity. The biological activity of the ocular tissue microsomes were compared with either indomethacin-treated human platelet microsomes (for TxA2-like activity) or rabbit aorta microsomes (for PGI2-like activity) under appropriate incubation conditions. No evidence could be found for the formation of TxA2-like activity from PG endoperoxides by the IBIM. In contrast, when the IBIM were incubated with PGH2 for 1 min at 22 degrees C without cofactors, PGI2-like activity was produced, causing profound relaxation of the isolated dog coronary artery preparation without contracting the rabbit aorta and inhibiting arachidonic acid-induced platelet aggregation. Equivalent quantities of boiled IBIM failed to alter the biological activity of PGH2 under identical conditions. Tranylcypromine (500 microgram/ml) completely abolished the appearance of PGI2-like activity. Furthermore, the PGI2-like activity found was stable for 10 min at 22 degrees C at pH 8.5 but completely lost under similar conditions at pH 5.5. It is concluded that microsomal preparations of normal bovine iris-ciliary body can synthesize PGI2-like activity in substantial amounts but not TxA2-like activity.  相似文献   
83.
Insect-resistant transgenic cotton has been commercialized for two decades. Most of the introduced cultivars express Bt gene(s) constitutively under the control of 35S promoter in whole-plant tissues. However, there have been other promoters considered by researchers to confine the toxin expression to targeted organ and tissues. We developed a triple-gene construct including GNA, cry1Ac and cp4 epsps genes. We attempted to confine cry1Ac expression to insect biting sites by cloning it to downstream of a wound-inducible promoter isolated from Asparagus officinalis (AoPR1). Moreover, to broaden the range of resistance, GNA was driven by the 35S promoter to target the sap-sucking insects like aphids which impose large losses in cotton production. To select the transformants in selection medium and for glyphosate tolerance, GNA and cry1Ac genes were accompanied with cp4 epsps gene. Two binary vectors harboring desired genes were constructed and utilized in the study (pGTGNAoC1AC and pGTGN35C1AC). Transformation of cultivar GSN-12 was carried out by employing Agrobacterium tumefaciens strain EHA105. Plantlets were primarily screened under glyphosate (N-phosphonomethyl glycine) selection pressure and subsequently subjected to molecular and biotoxicity assays. Introduction of cry1Ac and GNA to cotton plant conferred resistance to Spodoptera littoralis and Aphis gossypii Glover. Restriction of cry1Ac toxin protein to insect biting sites along with a plant lectin attributes significantly to insect pest management strategies.  相似文献   
84.
Synthetic sedimentation velocity boundaries were generated using finite-element solutions to the original and modified forms of the Lamm equation. Situations modeled included ideal single- and multicomponent samples, concentration-dependent samples, noninteracting multicomponent samples, and reversibly self-associating samples. Synthetic boundaries subsequently were analyzed using the method of van Holde and Weischet, and results were compared against known input parameters. Results indicate that this analytical method provides rigorous diagnostics for virtually every type of sample complexity encountered experimentally. Accordingly, both the power and utility of sedimentation velocity experiments have been significantly expanded.  相似文献   
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Protein aggregation into oligomers and mature fibrils are associated with more than 20 diseases in humans. The interactions between cationic surfactants dodecyltrimethylammonium bromide (DTAB) and tetradecyltrimethylammonium bromide (TTAB) with varying alkyl chain lengths and bovine liver catalase (BLC) were examined by various biophysical approaches. The delicate coordination of electrostatic and hydrophobic interactions with protein, play imperative role in aggregation. In this article, we have reconnoitered the relation between charge, hydrophobicity and cationic surfactants DTAB and TTAB on BLC at pH 7.4 and 9.4 which are two and four units above pI, respectively. We have used techniques like turbidity, Rayleigh light scattering, far-UV CD, ThT, ANS, Congo red binding assay, DLS, and transmission electron microscopy. The low concentration ranges of DTAB (0–600 μM) and TTAB (0–250 μM) were observed to increase aggregation at pH 9.4. Nevertheless, at pH 7.4 only TTAB was capable of inducing aggregate. DTAB did not produce any significant change in secondary structure at pH 7.4 suggestive of the role of respective charges on surfactants and protein according to the pI and alkyl chain length. The morphology of aggregates was further determined by TEM, which proved the existence of a fibrillar structure. The surfactants interaction with BLC was primarily electrostatic as examined by ITC. Our work demystifies the critical role of charge as well as hydrophobicity in amyloid formation.  相似文献   
89.
Tuckerella japonica Ehara (Acari: Tetranychoidea: Tuckerellidae) was found on stems of seedling plants of Camellia sinensis (L.) O. Kuntze (Theaceae) in the continental USA. This mite is able to pierce exposed green periderm tissue with its paired stylets on 1- to 3- or 4-year-old stems where the outer bark had split longitudinally. The mite was not found on branches older than 3 or 4 years, where splitting diminished and, eventually, a uniform covering of bark was formed. The mouthparts of T. japonica were examined under scanning electron microscopy and their external morphology was compared with known Tetranychoidea. There were usually one or two feeding holes in an area where the female subsequently deposited one or more eggs. Females were observed defending the areas where their eggs and/or young occurred. This behavior along with potentially limited access to exposed periderm or availability of shoots in the rows of plants may restrict higher populations of T. japonica from becoming established. The potential of T. japonica as an economic pest remains unknown at this time.  相似文献   
90.
Purpose: Sulfur mustard (SM) lung is a heterogeneous disease associated with abnormal inflammatory immune responses. The Th17/Treg axis imbalance is associated with the pathogenesis of chronic inflammatory pulmonary disease. We aimed to determine the distribution of different Th17 and Treg cells in patients with SM lung and chronic obstructive pulmonary disease (COPD) and evaluate the clinical implications in this homeostasis. Methods: In this analytical cross-sectional study, CD4?+?Foxp3+?Treg and CD4+?IL-17+?Th17 cells were measured in peripheral blood mononuclear cells (PBMCs) and transbronchial biopsy (TBB) samples of 15 SM-exposed patients, 12 COPD and 13 healthy controls (HCs). The potential correlation between the ratio of Th17/Tregs and lung function was evaluated with multivariate logistic regression (MLR) analysis. Results: The frequency of CD4?+?FoxP3+?Tregs and CD4?+?IL-17+?Th17 was increased ~1.7-fold (8.71/4.95) and ~2.7-fold (1.028/0.371) respectively, in the PBMC of SM patients compared with the health controls (p?<?0.001). The results indicated that there were increases in the frequency of Th17 and Tregs cells in the patients with COPD versus the HC, that is, ~2.6-fold (0.987/0.371) and ~1.4-fold (7.12/4.95), respectively; but they did not reach to SM level (p?≥?0.05). Moreover, in the TBB samples, the CD4?+?IL-17+?Th17 and CD4+?FoxP3+?Tregs numbers were significantly higher in SM and COPD patients than HC (p?<?0.05). The Th17 and Treg cells were inversely correlated with forced expiratory volume in 1s (FEV1%) (r?=??0.351, p =?0.001; r?=??0.344, p?=?0.021) and FEV1/FVC (r?=??0.44, p?=?0.001; r?=??0.302, p?=?0.011), respectively. Instead, positive correlations were found between Treg/Th17 ratios and forced FEV1%pred (r?=?0.156, p?=?0.007), as well as FEV1/FVC ratio (r?=?0.334, p?=?0.006). Conclusions: The imbalance of Th17/Treg has a key role in immunopathogenesis of chronic phase of mustard lung disease.  相似文献   
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