Cadmium sulfide in a Mesoproterozoic terrestrial environment

Peer reviewedPostprin

AFOMP Policy Statement No. 3: recommendations for the education and training of medical physicists in AFOMP countries

AFOMP recognizes that clinical medical physicists should demonstrate that they are competent to practice their profession by obtaining appropriate education, training and supervised experience in the specialties of medical physics in which they practice, as well as having a basic knowledge of other specialties. To help its member countries to achieve this, AFOMP has developed this policy to provide guidance when developing medical physicist education and training programs. The policy is compatible with the standards being promoted by the International Organization for Medical Physics and the International Medical Physics Certification Board

AFOMP Policy Statement No. 3: recommendations for the education and training of medical physicists in AFOMP countries

AFOMP recognizes that clinical medical physicists should demonstrate that they are competent to practice their profession by obtaining appropriate education, training and supervised experience in the specialties of medical physics in which they practice, as well as having a basic knowledge of other specialties. To help its member countries to achieve this, AFOMP has developed this policy to provide guidance when developing medical physicist education and training programs. The policy is compatible with the standards being promoted by the International Organization for Medical Physics and the International Medical Physics Certification Board

AFOMP Policy Statement No. 4: Recommendations for continuing professional development systems for medical physicists in AFOMP countries

This policy statement, which is the fourth of a series of documents being prepared by the Asia-Oceania Federation of Organizations for Medical Physics Committees Professional Development Committee, gives guidance on how member countries could develop a continuing professional development system for ensuring that its clinical medical physicists are up-to-date in their knowledge and practice. It is not intended to be prescriptive as there are already several CPD systems successfully operated by AFOMP member countries and elsewhere that vary considerably in scope and structure according to local culture, practice and legislation but all of which are capable of ensuring that physicists are up-to-date. It is intended to be advisory and set out options for member countries to develop their individual CPD systems

Peptide Deformylase Inhibitors as Potent Antimycobacterial Agents

Peptide deformylase (PDF) catalyzes the hydrolytic removal of the N-terminal formyl group from nascent proteins. This is an essential step in bacterial protein synthesis, making PDF an attractive target for antibacterial drug development. Essentiality of the def gene, encoding PDF from Mycobacterium tuberculosis, was demonstrated through genetic knockout experiments with Mycobacterium bovis BCG. PDF from M. tuberculosis strain H37Rv was cloned, expressed, and purified as an N-terminal histidine-tagged recombinant protein in Escherichia coli. A novel class of PDF inhibitors (PDF-I), the N-alkyl urea hydroxamic acids, were synthesized and evaluated for their activities against the M. tuberculosis PDF enzyme as well as their antimycobacterial effects. Several compounds from the new class had 50% inhibitory concentration (IC(50)) values of <100 nM. Some of the PDF-I displayed antibacterial activity against M. tuberculosis, including MDR strains with MIC(90) values of <1 μM. Pharmacokinetic studies of potential leads showed that the compounds were orally bioavailable. Spontaneous resistance towards these inhibitors arose at a frequency of ≤5 × 10(−7) in M. bovis BCG. DNA sequence analysis of several spontaneous PDF-I-resistant mutants revealed that half of the mutants had acquired point mutations in their formyl methyltransferase gene (fmt), which formylated Met-tRNA. The results from this study validate M. tuberculosis PDF as a drug target and suggest that this class of compounds have the potential to be developed as novel antimycobacterial agents

Design, Synthesis, and Pharmacological Evaluation of a Novel Series of Pyridopyrazine-1,6-dione γ‑Secretase Modulators

Herein we describe the design and synthesis of a novel series of γ-secretase modulators (GSMs) that incorporates a pyridopiperazine-1,6-dione ring system. To align improved potency with favorable ADME and in vitro safety, we applied prospective physicochemical property-driven design coupled with parallel medicinal chemistry techniques to arrive at a novel series containing a conformationally restricted core. Lead compound <b>51</b> exhibited good in vitro potency and ADME, which translated into a favorable in vivo pharmacokinetic profile. Furthermore, robust reduction of brain Aβ42 was observed in guinea pig at 30 mg/kg dosed orally. Through chemical biology efforts involving the design and synthesis of a clickable photoreactive probe, we demonstrated specific labeling of the presenilin N-terminal fragment (PS1-NTF) within the γ-secretase complex, thus gaining insight into the binding site of this series of GSMs