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1.  Antiretroviral therapy CNS penetration and HIV-1–associated CNS disease 
Neurology  2011;76(8):693-700.
The impact of different antiretroviral agents on the risk of developing or surviving CNS disease remains unknown. The aim of this study was to investigate whether using antiretroviral regimens with higher CNS penetration effectiveness (CPE) scores was associated with reduced incidence of CNS disease and improved survival in the UK Collaborative HIV Cohort (CHIC) Study.
Adults without previous CNS disease, who commenced combination antiretroviral therapy (cART) between 1996 and 2008, were included (n = 22,356). Initial and most recent cART CPE scores were calculated. CNS diseases were HIV encephalopathy (HIVe), progressive multifocal leukoencephalopathy (PML), cerebral toxoplasmosis (TOXO), and cryptococcal meningitis (CRYPTO). Incidence rates and overall survival were stratified by CPE score. A multivariable Poisson regression model was used to identify independent associations.
The median (interquartile range) CPE score for initial cART regimen increased from 7 (5–8) in 1996–1997 to 9 (8–10) in 2000–2001 and subsequently declined to 6 (7–8) in 2006–2008. Differences in gender, HIV acquisition risk group, and ethnicity existed between CPE score strata. A total of 251 subjects were diagnosed with a CNS disease (HIVe 80; TOXO 59; CRYPTO 56; PML 54). CNS diseases occurred more frequently in subjects prescribed regimens with CPE scores ≤4, and less frequently in those with scores ≥10; however, these differences were nonsignificant. Initial and most recent cART CPE scores ≤4 were independently associated with increased risk of death.
Clinical status at time of commencing cART influences antiretroviral selection and CPE score. This information should be considered when utilizing CPE scores for retrospective analyses.
PMCID: PMC3053326  PMID: 21339496
3.  Ecological Genomics of Marine Picocyanobacteria†  
Summary: Marine picocyanobacteria of the genera Prochlorococcus and Synechococcus numerically dominate the picophytoplankton of the world ocean, making a key contribution to global primary production. Prochlorococcus was isolated around 20 years ago and is probably the most abundant photosynthetic organism on Earth. The genus comprises specific ecotypes which are phylogenetically distinct and differ markedly in their photophysiology, allowing growth over a broad range of light and nutrient conditions within the 45°N to 40°S latitudinal belt that they occupy. Synechococcus and Prochlorococcus are closely related, together forming a discrete picophytoplankton clade, but are distinguishable by their possession of dissimilar light-harvesting apparatuses and differences in cell size and elemental composition. Synechococcus strains have a ubiquitous oceanic distribution compared to that of Prochlorococcus strains and are characterized by phylogenetically discrete lineages with a wide range of pigmentation. In this review, we put our current knowledge of marine picocyanobacterial genomics into an environmental context and present previously unpublished genomic information arising from extensive genomic comparisons in order to provide insights into the adaptations of these marine microbes to their environment and how they are reflected at the genomic level.
PMCID: PMC2698417  PMID: 19487728
4.  Photosynthesis of Prochlorothrix hollandica under Sulfide-Rich Anoxic Conditions 
The photosynthetic activity and photosystem II fluorescence of Prochlorothrix hollandica were studied under anoxic, sulfide-rich conditions. Oxygenic photosynthetic activity with water as the electron donor was highly resistant to inhibition by sulfide. Cells still retained 50% of their oxygenic photosynthetic activity at >1 mM sulfide. In the presence of DCMU [N-(3,4-dichlorophenyl)-N(prm1)-dimethylurea], an inhibitor of photosystem II activity, P. hollandica cells exhibited a low but significant anoxygenic photosynthetic activity when sulfide was present. This activity increased with higher sulfide concentrations and reached maximal rates at concentrations exceeding 1 mM sulfide. The effects of hydroxylamine on both oxygen evolution and fluorescence induction kinetics were similar to those observed for sulfide. It was concluded that the oxidizing site of photosystem II was the site of sulfide action leading to reduced or even fully inhibited electron donation to photosystem II. These observations bear similarity to the situation in some cyanobacteria in which both hydroxylamine and sulfide inhibit electron donation from H(inf2)O to P(inf680). The high resistance of photosystem II to sulfide is related to the hydrophobic nature of the manganese-stabilizing protein in P. hollandica (T. S. Mor, A. F. Post, and I. Ohad, Biochim. Biophys. Acta 1141:206-212, 1993). The observed sulfide tolerance of P. hollandica may confer a competitive advantage in its natural environment, where it forms a dominant fraction of phytoplankton in waters in which sulfide presence is a recurring phenomenon.
PMCID: PMC1389245  PMID: 16535689
6.  Psychological aspects of geriatrics. 
Postgraduate Medical Journal  1968;44(510):307-318.
PMCID: PMC2466395  PMID: 4872904
7.  Learning from old age. 
PMCID: PMC1811209  PMID: 5441964
8.  Management of senile psychiatric disorders. 
British Medical Journal  1968;4(5631):627-630.
PMCID: PMC1912500  PMID: 5723369
9.  Influence of Phosphate Compounds on Certain Fungi and Their Preservative Effects on Fresh Cherry Fruits (Prunus cerasus, L.) 
Applied Microbiology  1968;16(1):138-142.
Studies were conducted to ascertain the retarding effects of four phosphate compounds (sodium hexametaphosphate, sodium tripolyphosphate, sodium tetraphosphate, and tetrasodium pyrophosphate) on molding of fresh cherries (Prunus cerasus, L.). In vitro studies on their antimycotic effects against the most common fungal spoilers, Penicillium expansum, Rhizopus nigricans, and Botrytis sp., were also carried out. Sodium tetraphosphate appeared to be the most effective compound in preserving cherries and also had the greatest antimycotic effects in the in vitro studies. A 10% concentration, when applied as a dip, inhibited fungal growth on fresh cherries for up to 30 days of storage at 1.1 C (34 F) and a relative humidity of 94%, whereas untreated controls showed fungal growth at 14 days. Following in order of effectiveness were sodium hexametaphosphate, sodium tripolyphosphate, and tetrasodium pyrophosphate.
PMCID: PMC547333  PMID: 4295176
10.  Simple Medium for the Selective Isolation of Bacteroides and Related Organisms, and Their Occurrence in Sewage 
Applied Microbiology  1967;15(2):213-218.
A medium composed of 0.009% sodium azide, 0.07% sodium deoxycholate, and 0.0007% ethyl violet in Brain Heart Infusion Agar (Difco) and a process of incubation in an atmosphere of 90% N2 and 10% CO2 for the selective isolation of certain members of the intestinal bacteroides are described. The medium appears to select predominantly members of the genus Bacteroides and a few of the genus Sphaerophorus. A survey of the occurrence of these organisms in sewage and various stages of sewage treatment indicates that they survive complete sewage treatment in low numbers and that their rate of decline parallels that of the coliforms. Large numbers were recovered from sludge digestion tanks, suggesting a possible role in the anaerobic breakdown of organic matter.
PMCID: PMC546880  PMID: 6029824
12.  Influence of Sodium Hexametaphosphate on Selected Bacteria 
Applied Microbiology  1963;11(5):430-435.
Sodium hexametaphosphate (HEX), the solvent of calcium alginate wool used in swabbing inanimate surfaces was studied relative to its effect on various bacterial populations, both pure cultures and wild. It was found that bacteria in wild populations were greatly inhibited, and that a percentage reduction of count was directly related to concentration of HEX. Most gram-positive bacteria were prevented from growing on a medium containing 0.1% HEX. This, or a higher concentration, occurred in the final medium when the method recommended in Standard Methods for the Examination of Dairy Products was followed. Growth of Sarcina lutea occurred on media with higher concentrations than that of inhibition (0.05%), if MgSO4·7H2O was incorporated in the medium. Gram-negative bacteria were capable of growing in higher concentrations, even up to 10% HEX. A large percentage of the cells of some strains (represented by Pseudomonas fluorescens) were lysed on contact with HEX. Lysis could be prevented by the addition of NaCl or MgSO4·7H2O. The evidence presented suggests that HEX, a phosphate-glass water-softening sequestrant, interferes with divalent cation metabolism, notably magnesium ion, and possibly others, producing cell division inhibition and loss of cell-wall integrity. The mechanism of action was not elucidated.
PMCID: PMC1058021  PMID: 14063787

Results 1-12 (12)