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Several letter to the editors are presented in response to the article "Detecting Helping Anxiety" by Michael Poole, "Hallmark Help Please" by Paul Emmison in October 2016 issue and one related to Minelab CTX 3030 metal detector.

Nanoscale separation techniques, nanoscale packed capillary columns (75 μm id), and capillary zone electrophoresis (CZE), on-line with electrospray mass spectrometry (ESI/MS), were applied to the separation of a series of ten macrolide antibiotics. Both techniques use sub-microliter-per-minute flow rates through the analytical column and therefore require an electrospray probe that incorporates coaxial sheath flow. Positive ion electrospray mass spectra of these compounds yielded mainly protonated molecules. Fragmentation to yield structurally significant fragment ions was achieved by collision-induced dissociation (CID) at increased skimmer voltages. Separations were achieved using both techniques, with CZE/ESI/MS showing improved peak shapes and detection limits combined with faster analysis times. Nonescale packed capillary columns provided better chromatographic resolution and was less susceptible to peak broadening caused by overloading of the analytes.

Macrolide 2'-phosphotransferase [MPH(2')] was purified 90-fold from an erythromycin-resistant strain of Escherichia coli, and its enzymatic properties were investigated. MPH(2') is an inducible intracellular enzyme which showed high levels of activity with 14-member-ring macrolides and extremely low levels with 16-member-ring macrolides. The optimum pH for inactivation of oleandomycin was 8.2, and the optimum temperature of the reaction was 40 degrees C. Enzyme activity was lost by heat treatment at 50 degrees C for 1 min. The isoelectric point and molecular weight of the enzyme were 5.3 and 34,000, respectively. Purine nucleotides, such as GTP, ITP, and ATP, were effective as cofactors in the inactivation of macrolides. Iodine, EDTA, or divalent cations inhibited MPH(2') activity.

The paper attempts to establish the importance of addressing what Chalmers (1995) calls the 'easy problems' of consciousness, at the expense of the 'hard problem'. One pragmatic argument and two philosophical arguments are presented to defend this approach to consciousness, and three major theories of consciousness are criticized in this light. Finally, it is shown that concentration on the easy problems does not lead to eliminativism with respect to consciousness.

Three cases of gastritis glandularis et cystica profunda are presented, two associated with severe chronic gastritis and the other with invasive gastric carcinoma and chronic gastritis. This poorly known entity consists of benign downgrowths of deep gastric glands through the muscularis mucosae into, the submucosa. The pattern is primarily adenomatous with secondary cyst formation, which varies in extent and severity. The lesion is related to the chronic gastritis but why it should occur so rarely in such a common condition as chronic gastritis remains obscure. More documented cases are needed before a meaningful analysis can be attempted.

Beta-Lactam antibiotics and the crude enzyme were mixed in deuterium oxide and placed in a nuclear magnetic resonance tube. The change of the nuclear magnetic resonance spectrum during the enzymatic reaction was then analyzed to determine beta-lactamase activity. By using beta-lactam antibiotics such as penicillins, cephalosporins, and cephamycins as substrates, a comparison of the beta-lactamase activities was made between the nuclear magnetic resonance spectrometric assay and the iodometric assay. There was a close correlation between these two methods.

Eight cases of papillary serous cystadenoma arising in paramesonephric parovarian cysts are presented. None of these benign lesions were diagnosed preoperatively as such and were only detected pathologically. In only one case was the tumor-bearing cyst symptomatic owing to its large size. The etiology, pathogenesis, and evolution of this lesion are briefly discussed.

Clinical isolates of Pseudomonas aeruginosa were examined for the basis of impermeability-type aminoglycoside resistance. Two apparently related burn isolate strains with high-level (strain 8803) and low-level (strain 13934) gentamicin resistance each had a plasmid. Transformation of the plasmid from either strain to P. aeruginosa PAO503 resulted in low-level gentamicin resistance. No mechanism for this resistance could be determined. Low-level gentamicin and streptomycin resistance from strain 8803 (but not 13934) was transduced with phage E79.tv2 to PAO503 without transfer of plasmid DNA. Transductants like strain 8803 showed absence or reduction of the lipopolysaccharide (LPS) "ladder" pattern of PAO503, had a change in chemical composition of LPS, and, like strain 8803, had a reduced capability to accumulate streptomycin. Comparison of the resistant clinical isolates 8803 and P10 with the apparently related but less-resistant strains 13934 and P10R, respectively, showed the latter strains had LPS ladder patterns and the former strains did not. Strain 8803 had normal outer membrane protein profiles, electron transport components, and transmembrane electrical potential relative to PAO503 and has been previously shown to have no detectable gentamicin-modifying enzymes and normal protein synthesis. We conclude that low-level impermeability-type aminoglycoside resistance in P. aeruginosa results from conversion of smooth LPS to superficial or deeper rough LPS phenotypes. High-level resistance apparently results from a plasmid-specified, but as yet unknown, mechanism combined with the preceding change in LPS structure.

The antibacterial activity of sisomicin (SS), a new aminoglycoside antibiotic active toward clinical isolates of Pseudomonas aeruginosa, was determined and compared with that of the gentamicin C complex. Both drugs were effective against these strains and showed almost the same antibacterial activity. A few strains were found to be resistant to SS. The antibiotic was inactivated by a cell-free extract from the SS-resistant strains due to acetylation of the drug. Comparative studies of the inactivation of the drugs which lack a 6'-amino group in the amino sugar linked to 2-deoxystreptamine strongly suggested that SS inactivation was due to acetylation of the 6'-amino group of the 4',5'-didehydropurpurosamine moiety.