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91.
Four new lanostane triterpenes, colossolactone V (1), colossolactone VI (2), colossolactone VII (3), and colossolactone VIII (4), were isolated from the fruiting bodies of the Vietnamese mushroom Ganoderma colossum, together with the known compound colossolactone E (5). The structures of 1- 4 were assigned on the basis of spectroscopic evidence, and their absolute configurations were determined by CD spectroscopy and the Mosher ester method. Compounds 1- 5, as well as two previously isolated compounds [schisanlactone A (6) and colossolactone G (7)] from the same mushroom, were evaluated for inhibition of HIV-1 protease, with IC 50 values for the most potent compounds ranging from 5 to 13 microg/mL. 相似文献
92.
Meroditerpenoids and derivatives from the brown alga Cystoseira baccata and their antifouling properties 总被引:1,自引:0,他引:1
Mokrini R Mesaoud MB Daoudi M Hellio C Maréchal JP El Hattab M Ortalo-Magné A Piovetti L Culioli G 《Journal of natural products》2008,71(11):1806-1811
The brown alga Cystoseira baccata harvested along the Atlantic coasts of Morocco yielded seven new meroditerpenoids (1-4) and derivatives (5-7), whose chemical structures were elucidated mainly by 2D NMR and mass spectrometry. Surprisingly, for all these compounds, which possess a bicyclo[4.3.0]nonane ring system, a trans fusion of the bicyclic system was deduced by stereochemical studies even though such compounds isolated from Cystoseira species are known to have a typical cis orientation for the bridgehead methyls. The antifouling and antibacterial activities of compounds 1-5 and 7 were evaluated, as well as their toxicity toward nontarget species. Compounds 4, 5, and 7 showed antifouling activities against growth of microalgae, macroalgal settlement, and mussel phenoloxidase activity, while being nontoxic to larvae of sea urchins and oysters. 相似文献
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Abdallah MA Abdullah HI Kang S Taylor DD Nakajima ST Gercel-Taylor C 《Fertility and sterility》2007,87(4):978-981
We describe our experience of over 300 cycles of preimplantation genetic diagnosis (PGD) and report clinical pregnancy rates (35%-67%) that support using this technology to screen for genetic disorders and chromosomal abnormalities. In clinical practice for over ten years, PGD offers couples the earliest form of genetic screening and may help improve ongoing pregnancy rates in poor-prognosis patients. 相似文献
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96.
Abdullah Alhendal Randa Abd Almoaeen Mohamed Rashad Ali Husain Fouzi Mouffouk Zahoor Ahmad 《RSC advances》2022,12(28):18077
This work describes the preparation of an analytical microextraction sorbent using a simple and versatile sol–gel hybrid composite, i.e., aramid oligomers wrapping multi-walled carbon nanotubes (CNTs) covalently bonded to a porous silica network. To overcome the inherent shortcomings of the CNTs'' solubility and dispersion in both organic phases and in the sol–gel solution, the outer surface of the CNTs was initially functionalized with carboxylic acid groups and then reacted with both aramid oligomers and 3-aminopropyl triethoxysilane (APTES). The obtained sorbent was characterized by FT-IR, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Using sol–gel chemistry, the functionalized CNTs were coated onto SPME fibers and used in conjunction with GC-MS for the analysis of polycyclic aromatic hydrocarbons (PAHs) in water and soil samples. Excellent repeatability (run-to-run RSD% ∼ 8) and reproducibility (fiber-to-fiber RSD% ∼ 6) were achieved in addition to low LODs (0.10–0.30 ng mL−1) and noticeable recovery%. The present method of sorbent preparation led to enhanced thermal and chemical stabilities, a long sorbent lifetime and good affinity towards PAHs. Moreover, the present sorbent enhanced the extraction capability by more than 30% compared to that of commercially available PDMS counterparts.This work describes the preparation of an analytical microextraction sorbent using a simple and versatile sol–gel hybrid composite, i.e., aramid oligomers wrapping multi-walled carbon nanotubes (CNTs) covalently bonded to a porous silica network. 相似文献
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99.
Sk Masum Billah Tarana E. Ferdous Abu Bakkar Siddique Camille RaynesGreenow Patrick Kelly Nuzhat Choudhury Tahmeed Ahmed Stuart Gillespie John Hoddinott Rukhsana Haider Purnima Menon Shams El Arifeen Michael J. Dibley 《Maternal & child nutrition》2022,18(3)
Exclusive breastfeeding (EBF) for the first 6 months has established benefits, yet had slow improvements globally. Little is known about electronic job aid‐assisted counselling to support EBF. As a secondary outcome of a cluster randomized controlled trial in Bangladesh, we assessed the effect of electronic job aid‐supported nutrition counselling and practical demonstration on EBF. We randomized pregnant women to one of five study arms in the trial and followed mother–child dyads until 2 years of age. Community health workers (CHWs) provided breastfeeding counselling with or without prenatal and complementary nutrient supplements in all four intervention arms. The comparison arm continued with the usual practice where mothers could receive nutrition counselling at routine antenatal and postnatal care, and during careseeking for childhood illnesses. We assessed breastfeeding indicators at birth and monthly until the child was 6 months old, in both intervention and comparison arms. To evaluate the effect of nutrition counselling on breastfeeding, we combined all four intervention arms and compared them with the comparison arm. Intervention newborns had half the risk (relative risk [RR]: 0.54, 95% confidence interval [CI]: 0.39, 0.76) of receiving prelacteal feeds than those in the comparison arm. EBF declined steeply in the comparison arm after 3 months of age. EBF was 16% higher in the intervention than the comparison arm at 4 months (RR: 1.16, 95% CI: 1.08, 1.23) and 22% higher at 5 months of age (RR: 1.22, 95% CI: 1.12, 1.33). Maternal background and household characteristics did not modify the intervention effect, and we observed no difference in EBF among caesarean versus vaginal births. Breastfeeding counselling and practical demonstration using an electronic job aid by CHWs are promising interventions to improve EBF and are scalable into existing community‐based programmes. 相似文献
100.
Hani Z. Asfour Nabil A. Alhakamy Osama A. A. Ahmed Usama A. Fahmy Shadab Md Mohamed A. El-Moselhy Waleed Y. Rizg Adel F. Alghaith Basma G. Eid Ashraf B. Abdel-Naim 《Drug delivery》2022,29(1):1892
The present study aimed to design and optimize, a nanoconjugate of gabapentin (GPN)-melittin (MLT) and to evaluate its healing activity in rat diabetic wounds. To explore the wound healing potency of GPN-MLT nanoconjugate, an in vivo study was carried out. Diabetic rats were subjected to excision wounds and received daily topical treatment with conventional formulations of GPN, MLT, GPN-MLT nanoconjugate and a marketed formula. The outcome of the in vivo study showed an expedited wound contraction in GPN-MLT-treated animals. This was confirmed histologically. The nanoconjugate formula exhibited antioxidant activities as evidenced by preventing malondialdehyde (MDA) accumulation and superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzymatic exhaustion. Further, the nanoconjugate showed superior anti-inflammatory activity as it inhibited the expression of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). This is in addition to enhancement of proliferation as indicated by increased expression of transforming growth factor-β (TGF- β), vascular endothelial growth factor-A (VEGF-A) and platelet-derived growth factor receptor-β (PDGFRB). Also, nanoconjugate enhanced hydroxyproline concentration and mRNA expression of collagen type 1 alpha 1 (Col 1A1). In conclusion, a GPN-MLT nanoconjugate was optimized with respect to particle size. Analysis of pharmacokinetic attributes showed the mean particle size of optimized nanoconjugate as 156.9 nm. The nanoconjugate exhibited potent wound healing activities in diabetic rats. This, at least partly, involve enhanced antioxidant, anti-inflammatory, proliferative and pro-collagen activities. This may help to develop novel formulae that could accelerate wound healing in diabetes. 相似文献