Pneumocystis jirovecii pneumonia (PCP) is an important opportunistic infection in patients infected with HIV, but its burden is incompletely characterized in those areas of sub-Saharan Africa where HIV is prevalent. We explored the prevalence of both PCP in HIV-infected adults admitted with pneumonia to a tertiary-care hospital in Uganda and of putative P. jirovecii drug resistance by mutations...

Since the late 1970s pyrimethamine-sulfadoxine (PS; FansidarTM Hoffman-LaRoche, Basel) has been used as first line therapy for uncomplicated malaria in the Amazon basin. Unfortunately, resistance has developed over the last ten years in many regions of the Amazon and PS is no longer recommended for use in Brazil. In vitro resistance to pyrimethamine and cycloguanil (the active metabolite of pro...

Discrete Hahn polynomials (DHPs) and their moments are considered to be one of the efficient orthogonal they applied in various scientific areas such as image processing feature extraction. Commonly, DHPs used object representation; however, suffer from problem numerical instability when moment order becomes large. In this paper, an operative method compute basis is proposed high orders. This p...

To the Editor: Diversity of genotypes among Pneumocystis jirovecii (human-specifi c Pneumo-cystis species) isolates mainly involves internal transcribed spacer (ITS) loci (1). Type Eg, one of the most frequently detected ITS genotypes, has been found worldwide (2). The locus of dihydropteroate synthase (DHPS) is also of interest because DHPS is the target of sulfonamides, the main drugs used to...

We report herein that 4-alkyl-1,4-dihydropyridines (alkyl-DHPs) can directly reach an electronically excited state upon light absorption and trigger the generation of C(sp3 )-centered radicals without the need for an external photocatalyst. Selective excitation with a violet-light-emitting diode turns alkyl-DHPs into strong reducing agents that can activate reagents through single-electron tran...

The resistance of Plasmodium falciparum to sulfadoxine-pyrimethamine (SP) is an emerging public health threat. Resistance to these drugs is associated with point mutations in the genes encoding dihydropteroate synthase (DHPS) and dihydrofolate reductase (DHFR). We describe here an assay using real-time PCR and sequence-specific probes that detects these mutations. Using DNA from plasmids, cultu...

Dihydropyrazines (DHPs), which generate hydroxyl and carbon-centered radicals, cleaved DNA single-strand. It is new knowledge that DHPs were recently determined to produce 8-hydroxydeoxyguanosine. The remarkable increase in the DNA strand-cleavage activity upon the addition of Cu2+ suggests that the primary reactive species is carbon-centered radicals rather than the hydroxyl radical generated ...

The nucleotide sequence analysis of the dihydropteroate synthase (DHPS) gene of six diaminodiphenylsulfone-resistant Mycobacterium leprae strains revealed that the mutation was limited at highly conserved amino acid residues 53 or 55. Though the mutation at amino acid residue 55 or its homologous site has been reported in other bacteria, the mutation at residue 53 is the first case in bacteria....

The need for new antimicrobials is great in face of a growing pool of resistant pathogenic organisms. This review will address the potential for antimicrobial therapy based on polypharmacological activities within the currently utilized bacterial biosynthetic folate pathway. The folate metabolic pathway leads to synthesis of required precursors for cellular function and contains a critical node...