Species radiations, despite immense phenotypic variation, can be difficult to resolve phylogenetically when genetic change poorly matches the rapidity of diversification. Genomic potential furnished by palaeopolyploidy, and relative roles for adaptation, random drift and hybridisation in the apportionment of genetic variation, remain poorly understood factors. Here, we study these aspects in a model radiation, Syzygium, the most species-rich tree genus worldwide.
View Article and Find Full Text PDFIn 2002, the Physician Charter on Medical Professionalism was published to provide physicians with guidance for decision making in a rapidly changing environment. Feedback from physicians indicated that they were unable to fully live up to the principles in the 2002 charter partly because of their employing or affiliated health care organizations. A multistakeholder group has developed a Charter on Professionalism for Health Care Organizations, which may provide more guidance than charters for individual disciplines, given the current structure of health care delivery systems.
View Article and Find Full Text PDFAustralia's Great Sandy Region is of international significance containing two World Heritage areas and patches of rainforest growing on white sand. Previous broad-scale analysis found the Great Sandy biogeographic subregion contained a significantly more phylogenetically even subset of species than expected by chance contrasting with rainforest on white sand in Peru. This study aimed to test the patterns of rainforest diversity and relatedness at a finer scale and to investigate why we may find different patterns of phylogenetic evenness compared with rainforests on white sands in other parts of the world.
View Article and Find Full Text PDFMammalian α4 phosphoprotein binds to the protein phosphatase 2A catalytic subunit (PP2Ac) to regulate PP2A activity, and to poly(A)-binding protein (PABP) and progestin-inducible EDD E3 ubiquitin ligase. This study showed induction of the EDD protein by progesterone, 17β-estradiol and prolactin in breast cancer cells. Co-immunoprecipitation analyses, using lysates of COS-1 cells transfected with α4-deletion constructs, showed the α4 N-terminus binding to endogenous PP2Ac and PABP, and the C-terminus to EDD.
View Article and Find Full Text PDFGrowth of the human MCF-7 breast cancer cell line is highly dependent on L-arginine. We have reported that L-arginine, released from extracellular substrates by prolactin (PRL)- and 17β-estradiol (E2)-induced carboxypeptidase-D in the cell membrane, promotes nitric oxide (NO) production for MCF-7 cell survival. Arginine uptake is mediated by members of the cationic amino acid transporter (CAT) family and may coincide with induction of nitric oxide synthase (NOS) for the production of NO.
View Article and Find Full Text PDFA facile and mild reduction procedure is reported for the preparation of chiral allylic and propargyl alcohols in high enantiomeric purity. Under optimized conditions, alkynyl and alkenyl ketones were reduced by TarB-NO2 and NaBH4 at 25 °C in 1 h to produce chiral propargyl and allylic alcohols with enantiomeric excesses and yields up to 99%. In the case of α,β-unsaturated alkenyl ketones, α-substituted cycloalkenones were reduced with up to 99% ee, while more substituted and acyclic derivatives exhibited lower induction.
View Article and Find Full Text PDFPhotolysis of alpha-diazo-N-methoxy-N-methyl (Weinreb) beta-ketoamides derived from enantiomerically pure (EP) alpha-amino acids affords the corresponding EP beta-lactams via an intramolecular Wolff rearrangement. The photochemistry is promoted with either standard UV irradiation or through the use of a 100 W compact fluorescent light; the latter affords a safe and environmentally friendly alternative to standard photolysis conditions. A continuous-flow photochemical reactor made from inexpensive laboratory equipment reduced reaction times and was amenable to scale-up.
View Article and Find Full Text PDFMammalian alpha4 phosphoprotein, the homolog of yeast Tap42, is a component of the mammalian target-of-rapamycin (mTOR) pathway that regulates ribogenesis, the initiation of translation, and cell-cycle progression. alpha4 is known to interact with the catalytic subunit of protein phosphatase 2A (PP2Ac) and to regulate PP2A activity. Using alpha4 as bait in yeast two-hybrid screening of a human K562 erythroleukemia cDNA library, EDD (E3 isolated by differential display) E3 ubiquitin ligase was identified as a new protein partner of alpha4.
View Article and Find Full Text PDFDensity functional theory was used to explore the effects of aqueous solvation on the structure, vibrational frequencies, and the electronic absorption spectrum of 2-(4-methylimidazol-1-yl)-phenol (Me-ImPhOH), a chemical analogue of the cross-linked histidine-tyrosine Cu(B) ligand of cytochrome c oxidase. In addition, the phenolic-OH pK(a), the anodic redox potential for the biring radical/anion couple, and the phenolic-OH bond dissociation energy were calculated relative to phenol using a series of isodesmic reactions. In the gas phase, the imidazole moiety stabilizes the biring anion for all the models and greatly decreases the phenolic-OH pK(a) relative to phenol.
View Article and Find Full Text PDFProfessional medical associations (PMAs) play an essential role in defining and advancing health care standards. Their conferences, continuing medical education courses, practice guidelines, definitions of ethical norms, and public advocacy positions carry great weight with physicians and the public. Because many PMAs receive extensive funding from pharmaceutical and device companies, it is crucial that their guidelines manage both real and perceived conflict of interests.
View Article and Find Full Text PDFThe effects of aqueous solvation on the structure and vibrational frequencies of phenol, para-cresol, and their respective radicals are calculated at the B3LYP/6-31+G(d,p) level of theory using the conductor-like polarizable continuum model (C-PCM) alone and in combination with an explicit water molecule H-bonded to the phenolic oxygen. Calculated vibrational frequencies are compared to experimental frequencies obtained in aqueous buffer at high pH. For all models, the C-PCM provides the best overall agreement between theory and experiment at a modest computational effort, as demonstrated by the lowest mean absolute deviations in the computed frequencies.
View Article and Find Full Text PDFJ Contin Educ Health Prof
December 2005
The Council of Medical Specialty Societies (CMSS) recognizes the need for continuing medical education (CME) reform and intends to be actively engaged in that process. While recognizing that CME reform must involve many organizations, the CMSS and particularly the 23 societies that make up the CMSS are in a position to affect many of the needed changes. Of these, perhaps the most important is the need to link CME to a change in physician behavior and patient outcomes.
View Article and Find Full Text PDFSpeculation about the future of medicine is risky. Few would have predicted five years ago the sweeping changes that have occurred. Nonetheless, an analysis and projection of current trends would suggest that further substantial changes await us.
View Article and Find Full Text PDFTrans Am Clin Climatol Assoc
July 1997
Table 2 summarizes the apparent motivations of the five physician signers. While religion played a role and each individual had his own other motivations, patriotic feelings for the evolving nation were probably a major factor which has been down-played in the past. It was an exciting and heady time for the citizens of the colonies.
View Article and Find Full Text PDFTreatment with aminoglycosides is known to cause irreversible hearing loss, typically affecting higher-frequency hearing first and progressing to lower frequencies. Standardized methodology has not been developed for early detection of ototoxicity. Serial conventional (0.
View Article and Find Full Text PDFJ Gen Intern Med
August 1990
Study Objective: To test reports that beta blockers, particularly lipophilic forms, impair cognitive function and cause psychiatric disturbances.
Design: Randomized, double-blind, controlled crossover trial with eight-week treatment periods.
Patients: Sequential sample of 42 male veterans, with untreated diastolic blood pressures (DBP) between 90 and 110 mmHg, aged 35-64 years.