Comparative population genetic analyses suggest hybrid origin of Rhododendron pubicostatum,an endangered plant species with extremely small populations endemic to Yunnan,China

Gene flow between sympatric congeneric plants is thought to be very common and may pose serious threats to endangered species.In the present study,we evaluate the genetic diversity and divergence of three sympatric Rhododendron species in Jiaozi Mountain using newly developed microsatellites through the Illumina MiSeq sequencing approach.Genetic diversity of all three Rhododendron species studied was moderate in comparison to genetic parameters previously reported from species of this genus.Interestingly,genetic structure analysis of the three species identified a possible hybrid origin of the threatened Rh.pubicostatum.This sympatry should be considered a unimodal hybrid zone,since Rh.pubicostatum is predominant here.Unimodal hybrid zones are uncommon in Rhododendron,despite the fact that hybridization frequently occurs in the genus.Issues pertaining to the conservation of Rh.pubicostatum resulting from admixture of genetic material from its parental species are discussed.

Glutathione-depleted cyclodextrin pseudo-polyrotaxane nanoparticles for anti-inflammatory oxaliplatin(Ⅳ) prodrug delivery and enhanced colorectal cancer therapy

Oxaliplatin(Oxa) is the first-line chemotherapeutic drug for the treatment of colorectal cancer(CRC). However, long-term Oxa chemotherapy can induce inflammation and increase the levels of cyclooxygenase-2(COX-2) and prostaglandin E2(PGE2), which can promote tumor metastasis. Moreover,high glutathione(GSH) levels in CRC cells significantly reduce Oxa sensitivity and seriously restrict the clinical application of Oxa. Herein, an Oxa(Ⅳ) prodrug with anti-inflammatory properties(desmethyl naproxe, DN) and GSH-depleting cyclodextrin pseudo-polyrotaxane carriers were prepared and further self-assembled into micellar nanoparticles(designated DNPt@PPRI). The relesae of DN from DNPt@PPRI can reduce the level of PGE2 to inhibit inflammation and tumor metastasis by decreasing COX-2 protein,and also synergize with Oxa to inhibit tumor. More importantly, GSH depletion can reduce the detoxification of Oxa and further enhance chemotherapy-induced apoptosis. DNPt@PPRI have a good GSH depletion ability to enhance the sensitivity of Oxa, indicating a potential in the synergistic chemotherapy and chemo-sensitization of colorectal cancer.

2-Diphenylphosphinoyl-acetyl as a Remote Directing Group for the Highly Stereoselective Synthesis ofβ-Glycosides

Comprehensive Summary The configuration of the anomeric glycosidic linkages is crucial for maintaining the biological functions and activities of carbohydrate molecules.However,their stereochemistry control in glycosylation represents one of the most challenging tasks in carbohydrate chemistry.

Amelioration of imiquimod-induced psoriasis-like dermatitis in mice by DSW therapy inspired hydrogel

Psoriasis is a long-lasting and recurrent autoimmune disease which is incurable so far.Dead Sea water(DSW)therapy is an effective approach to help control the symptoms of psoriasis due to the abundant mineral ions in DSW,which inspired the material formulation in this study.Rubidium–Sodium alginate/Polyacrylamide hydrogels(Rb-SA/PAAm gels)composed of sodium alginate and polyacrylamide interpenetrating network structure with different concentrations of rubidium and certain magnesium and zinc content were prepared for the treatment of psoriasis.The obtained results suggest the good mechanical properties of the Rb-SA/PAAm gels including toughness and swelling performance.In terms of in vitro tests,the Rb-SA/PAAm gels not only show nontoxicity to human keratinocyte cell line(Hacats)but also inhibits the activity against inflammatory NF-κβ signaling pathway.Meanwhile,they can release Rb+which enable the Rb-SA/PAAm gels have better antibacterial ability to Streptococcus and Escherichia coli.The results obtained from in vivo tests indicate that these hydrogels could alleviate the symptoms of psoriasis caused by Imiquimod(IMQ)in mice by reducing the inflammatory factor in STAT3 pathway and therefore reduce the immune stimulation of the spleen.In conclusion,the 100Rb-SA/PAAm gel has demonstrated great potential to be a topical wettable dressing for psoriasis treatment.

Retraction notice to“Amelioration of imiquimod-induced psoriasis-like dermatitis in mice by DSW therapy inspired hydrogel”[BIOMAT 6(2021)299-311]

This article has been retracted:please see Elsevier Policy on Article Withdrawal(https://www.elsevier.com/about/our-business/policies/article-withdrawal).This article has been retracted at the request of all the Authors,the Editor-in-Chief and the owner of the journal.The article has been retracted because of the authors recently re-conducted partly the experiments and found that the anti-bacteria behavior of Rb+was not reproducible.As shown in Fig.1(see enclosed file),at a centration as high as 200 mM,the addition of single Rb+does not show anti-bacteria effect.In Fig.2(see enclosed file),the authors prepared a mixed solution containing Rb+,Mg2+and Zn2+with concentrations close to those(12 h)in the article,and found that the mixed solution does not show anti-bacterial effect either.The two figures indicate that the anti-bacteria effect of Rb+is not conclusive,which seriously impairs the rigidity of the paper.Considering complex factors influencing the experiments with hydrogels,there might be other effects on the anti-bacteria behavior.However,since the anti-bacteria effect of Rb+is incorrect,the authors would like to retract the published article.