Angiosperm male reproductive organs (anthers and pollen grains) have complex and interesting morphological features, but mechanisms that underlie their patterning are poorly understood. Here we report the isolation and characterization of a male sterile mutant of No Pollen 1 (NP1) in rice (Oryza sativa). The np1-4 mutant exhibited smaller anthers with a smooth cuticle surface, abnormal Ubisch bodies, and aborted pollen grains covered with irregular exine. Wild-type exine has two continuous layers; but np1-4 exine showed a discontinuous structure with large granules of varying size. Chemical analysis revealed reduction in most of the cutin monomers in np1-4 anthers, and less cuticular wax. Map-based cloning suggested that NP1 encodes a putative glucose-methanol-choline oxidoreductase; and expression analyses found NP1 preferentially expressed in the tapetal layer from stage 8 to stage 10 of anther development. Additionally, the expression of several genes involved in biosynthesis and in the transport of lipid monomers of sporopollenin and cutin was decreased in np1-4 mutant anthers. Taken together, these observations suggest that NP1 is required for anther cuticle formation, and for patterning of Ubisch bodies and the exine. We propose that products of NP1 are likely important metabolites in the development of Ubisch bodies and pollen exine, necessary for polymerization, assembly, or both.
The
sealed anatomical features of the eye and its physiological activity
that rapidly removes drugs are called anatomical and physiological
barriers, which are the cause of more than 90% of drug loss. This
aspect remains a critical issue in eye surface medication. Thus, promoting
tissue permeability of drugs as well as prolonging their retention
on the eye surface can improve their bioavailability and enhance their
therapeutic effects. Thanks to the existence of a negatively charged
mucin layer on the eye surface, several peptide-decorated polymeric
micelles were prepared to enhance the interaction between the micelle
and eye surface, thus prolonging the drug retention on the eye surface
and promoting its tissue permeability. Tacrolimus (also known as FK506)
is a hydrophobic macrolide immunosuppressant used to treat dry eye
syndrome and other eye diseases. However, its hydrophobic nature makes
its delivery as a topical eye surface medication difficult, with the
risk of side effects due to overdoses. Therefore, the aim of this
work is to evaluate the ability of FK506 micelles in promoting their
permeability on the eye surface. Our results showed that the positively
charged nanomicelles could significantly prolong FK506 retention on
the eye surface and enhance its corneal permeability in ex vivo and
in vivo conditions. FK506 nanomicelles exhibited superior curing effects
against dry eye diseases than the FK506 suspension and a commercial
FK506 formula. It exerted better inhibitory effects on eye surface
inflammation and corneal epithelium apoptosis when examined by a slip
lamp and a transferase-mediated dUTP nick end labeling assay, respectively.
Further assays revealed the higher suppressive effects on the expression
of several inflammation-related factors at an mRNA and protein level.
Hence, our results suggested that these positively charged nanomicelles
might be a good drug delivery system for ocular surface medication.
Longan is a delicious subtropical fruit with great health-beneficial effects. It has been utilized for disease prevention and health care since ancient age. To explore the chemicals responsible for the health benefits, water-soluble polysaccharides were extracted from longan flesh in this work. A pure polysaccharide (LPS1) was obtained through column purification. Analysis by gas chromatography showed LPS1 was a homopolysaccharide of glucose with glycosidic linkage of →6)-d-Glc-(1→. Nuclear magnetic resonance (NMR) spectra indicated that the configuration of anomeric carbon in glucose residual was α-form. The polysaccharide structure was further confirmed to be (1→6)-α-d-glucan by chemcial shift of C6. The molecular weight of LPS1 was calculated to be 108 kDa, which had 661 glucose residuals. Anticancer assay showed that LPS1 had anticancer activity against the growth of HepG2 cells to a certain extent. However, it did not show any cytotoxicity against MCF-7 breast cancer cells.
Silymarin has been shown to be a multiple-functional plant extract having antioxidant, hepatoprotective, hypolipidemic, antihypertensive, antidiabetic and anti-obesity effects. In recent years, the galactagogue effects of silymarin in animals and humans have also been revealed. This research was conducted to test whether dietary inclusion of silymarin during transition and lactation could impact reproductive performance of sows and to explore the underlying mechanisms. From day 108 of gestation to weaning, sows were randomly assigned to receive dietary treatment of silymarin (40 g/day) or not and were designated as control group (CGP, n = 55) or treatment group (TGP, n = 55). The results showed that piglets' average daily gain and average weaning weight were higher in TGP than CGP sows. In comparison with the CGP sows, the TGP sows had higher serum concentrations of catalase (CAT) on day 18 of lactation and glutathione peroxidase (GSH-Px) on day 7 of lactation. The TGP sows had lower concentration of TNF-α on day 7 of lactation and significantly lower concentration of IL-1β on day 18 of lactation than CGP sows. There was significantly higher serum concentration of PRL on day 7 of lactation in sows consuming silymarin than sows from the CGP group. On day 18 of lactation, the protein and urea contents in milk were significantly increased while the serum urea concentration was significantly decreased in TGP sows. In summary, our results indicate that silymarin supplementation during transition and lactation can increase circulating concentrations of PRL transiently, reduce oxidative stress, increase feed intake and enhance protein metabolism, thereby significantly increasing milk yield of sows and subsequently improving growth performance of their offsprings.
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