................................................................................................................... 46 Introduction .............................................................................................................. 47 5 Experimental section ................................................................................................ 49 2.3.1 Materials ...............

Self-assembled nanostructures of zwitterionic octaphosphanatoporphyrin 1, of either nanoparticles or nanorods, depending on small changes in the pH, is demonstrated based on the J-aggregates. Porphyrin 1 self-assembled into nanosphere aggregates with a diameter of about 70-80 nm in the pH range 5-7, and nanorod aggregates were observed at pH 8.5. Hydrogen bonding, π-π stacking and hydrophilic i...

Light hydrocarbons in water emulsions are formed in many gas refinery wastewaters, and its stability depends on some parameters such as temperature, pH and salinity. In this study, different surfactants have been used to prepare gas condensates in water emulsion along with four surfactant kinds namely, Span 80, Tween 80, CTAB, SDS and Span 80 and Tween 80 mixture. For this purpose,...

For determination of the activity of this enzyme (EC 4.2.1.24) in blood, pH dependency was evaluated by using whole blood and washed erythrocytes. The effects of assay methods, original and final pH, and use of sodium or potassium phosphate buffer were examined. The pattern of pH dependency differed for whole blood and washed erythrocytes, whether blood from normal or lead-exposed subjects was ...

The prevalence of pathogenic bacteria acquiring multidrug antibiotic resistance is a global health threat to mankind. This has motivated a renewed interest in developing alternatives to conventional antibiotics including bacteriophages (viruses) as therapeutic agents. The bacterium Clostridium difficile causes colon infection and is particularly difficult to treat with existing antibiotics; pha...

Fluoroquinolones were discovered in the 1960s as a derivative of the antimalarial drug chloroquine. Over the past 40 years, many fluoroquinolones have been developed for use in human and veterinary medicine. As with all classes of antibiotics, resistance to fluoroquinolones is a serious concern, and multiple avenues for resistance are being investigated. Resistance-associated point mutations in...

The themes presented in this Presidential address are introduced through masterpieces of medicine in art from the very earliest depictions to the modern day. The representations of medicine in art provide a commentary on the place of medicine in society and how it was viewed by society. Some artists used their work both to highlight important health issues of the time and as a " propaganda " to...

My third year of medical school, and I have finally begun my training. I am slowly learning to be a surgeon. I will open you up and search through the detritus of sickness, extirpate what is necessary, and leave in my wake a health of my own creation. There is power in that; a power that I have already glimpsed. Reaching out and calmly saying, "knife." Deliberately moving the scalpel across the...

In This Issue In This Issue Initiate then elongate tudies on yeast have provided significant insights into eukaryotic DNA replication, but it has been difficult to examine the process in more complex organisms. On page 225, Claycomb et al. have taken advantage of a peculiar aspect of insect biology to develop a new model for studying metazoan DNA replication, and have already made one surprisin...