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1.  Vegetarian diets and incidence of diabetes in the Adventist Health Study-2 
Aim
To evaluate the relationship of diet to incident diabetes among non-Black and Black participants in the Adventist Health Study-2.
Methods and Results
Participants were 15,200 men and 26,187 women (17.3% Blacks) across the U.S. and Canada who were free of diabetes and who provided demographic, anthropometric, lifestyle and dietary data. Participants were grouped as vegan, lacto ovo vegetarian, pesco vegetarian, semi-vegetarian or non-vegetarian (reference group). A follow-up questionnaire after two years elicited information on the development of diabetes. Cases of diabetes developed in 0.54% of vegans, 1.08% of lacto ovo vegetarians, 1.29% of pesco vegetarians, 0.92% of semi-vegetarians and 2.12% of non-vegetarians. Blacks had an increased risk compared to non-Blacks (odds ratio [OR] 1.364; 95% confidence interval [CI], 1.093–1.702). In multiple logistic regression analysis controlling for age, gender, education, income, television watching, physical activity, sleep, alcohol use, smoking and BMI, vegans (OR 0.381; 95% CI 0.236–0.617), lacto ovo vegetarians (OR 0.618; 95% CI 0.503–0.760) and semi-vegetarians (OR 0.486, 95% CI 0.312–0.755) had a lower risk of diabetes than non-vegetarians. In non-Blacks vegan, lacto ovo and semi-vegetarian diets were protective against diabetes (OR 0.429, 95% CI 0.249–0.740; OR 0.684, 95% CI 0.542–0.862; OR 0.501, 95% CI 0.303–0.827); among Blacks vegan and lacto ovo vegetarian diets were protective (OR 0.304, 95% CI 0.110–0.842; OR 0.472, 95% CI 0.270–0.825). These associations were strengthened when BMI was removed from the analyses.
Conclusion
Vegetarian diets (vegan, lacto ovo, semi-) were associated with a substantial and independent reduction in diabetes incidence. In Blacks the dimension of the protection associated with vegetarian diets was as great as the excess risk associated with Black ethnicity.
doi:10.1016/j.numecd.2011.07.004
PMCID: PMC3638849  PMID: 21983060
Vegetarianism; Black; African American; Diabetes; Ethnicity; Diet
2.  Diagnosis of bladder cancer by immunocytochemical detection of minichromosome maintenance protein-2 in cells retrieved from urine 
British Journal of Cancer  2012;107(8):1384-1391.
Background:
We tested the accuracy of immunocytochemistry (ICC) for minichromosome maintenance protein-2 (MCM-2) in diagnosing bladder cancer, using cells retrieved from urine.
Methods:
Adequate samples were obtained from 497 patients, the majority presenting with gross haematuria (GH) or undergoing cystoscopic surveillance (CS) following previous bladder cancer. We performed an initial study of 313 patients, followed by a validation study of 184 patients. In all cases, presence/absence of bladder cancer was established by cystoscopy/biopsy.
Results:
In the initial study, receiver operator characteristic analysis showed an area under the curve of 0.820 (P<0.0005) for the GH group and 0.821 (P<0.01) for the CS group. Optimal sensitivity/specificity were provided by threshold values of 50+ MCM-2-positive cells in GH samples and 200+ cells in CS samples, based on a minimum total cell number of 5000. Applying these thresholds to the validation data set gave 81.3% sensitivity, 76.0% specificity and 92.7% negative predictive value (NPV) in GH and 63.2% sensitivity, 89.9% specificity and 89.9% NPV in CS. Minichromosome maintenance protein-2 ICC provided clinically relevant improvements over urine cytology, with greater sensitivity in GH and greater specificity in CS (P=0.05).
Conclusions:
Minichromosome maintenance protein-2 ICC is a reproducible and accurate test that is suitable for both GH and CS patient groups.
doi:10.1038/bjc.2012.381
PMCID: PMC3494445  PMID: 22968648
bladder cancer; urothelial carcinoma; MCM-2; cytology; immunocytochemistry; biomarker
3.  Lessons from next-generation sequencing analysis in hematological malignancies 
Blood Cancer Journal  2013;3(7):e127-.
Next-generation sequencing has led to a revolution in the study of hematological malignancies with a substantial number of publications and discoveries in the last few years. Significant discoveries associated with disease diagnosis, risk stratification, clonal evolution and therapeutic intervention have been generated by this powerful technology. As part of the post-genomic era, sequencing analysis will likely become part of routine clinical testing and the challenge will ultimately be successfully transitioning from gene discovery to preventive and therapeutic intervention as part of individualized medicine strategies. In this report, we review recent advances in the understanding of hematological malignancies derived through genome-wide sequence analysis.
doi:10.1038/bcj.2013.26
PMCID: PMC3730204  PMID: 23872706
hematological malignancy; genome sequencing; RNA sequencing; clonal architecture
4.  Cloning and Characterization of a Hybridoma Secreting a 4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-Specific Monoclonal Antibody and Recombinant F(ab) 
Toxins  2013;5(3):568-589.
Smokeless tobacco products have been associated with increased risks of oro-pharyngeal cancers, due in part to the presence of tobacco-specific nitrosamines (TSNAs) such as 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). These potent carcinogens are formed during tobacco curing and as a result of direct nitrosation reactions that occur in the oral cavity. In the current work we describe the isolation and characterization of a hybridoma secreting a high-affinity, NNK-specific monoclonal antibody. A structurally-related benzoyl derivative was synthesized to facilitate coupling to NNK-carrier proteins, which were characterized for the presence of the N-nitroso group using the Griess reaction, and used to immunize BALB/c mice. Splenocytes from mice bearing NNK-specific antibodies were used to create hybridomas. Out of four, one was selected for subcloning and characterization. Approximately 99% of the monoclonal antibodies from this clone were competitively displaced from plate-bound NNKB conjugates in the presence of free NNK. The affinity of the monoclonal antibody to the NNKB conjugates was Kd = 2.93 nM as determined by surface plasmon resonance. Free nicotine was a poor competitor for the NNKB binding site. The heavy and light chain antibody F(ab) fragments were cloned, sequenced and inserted in tandem into an expression vector, with an FMDV Furin 2A cleavage site between them. Expression in HEK 293 cells revealed a functional F(ab) with similar binding features to that of the parent hybridoma. This study lays the groundwork for synthesizing transgenic tobacco that expresses carcinogen-sequestration properties, thereby rendering it less harmful to consumers.
doi:10.3390/toxins5030568
PMCID: PMC3705279  PMID: 23518474
TSNAs; F(ab); NNK; monoclonal antibody; 2A cleavage
5.  A molecular basis for the exquisite CD1d-restricted Antigen-specificity and functional responses of Natural Killer T cells 
Immunity  2011;34(3):327-339.
Natural Killer T (NKT) cells respond to a variety of CD1d-restricted antigens (Ags), although the basis for Ag discrimination by the NKT cell receptor (TCR) is unclear. Here we describe NKT TCR fine specificity against several closely related Ags, termed altered glycolipid ligands (AGLs), which differentially stimulate NKT cells. The structures of five ternary complexes all revealed similar docking. Acyl chain modifications did not affect the interaction, but reduced NKT cell proliferation, indicating an affect on Ag processing or presentation. Conversely, truncation of the phytosphingosine chain caused an induced fit mode of TCR binding that affected TCR affinity. Modifications in the glycosyl head group had a direct impact on the TCR interaction and associated cellular response, with ligand potency reflecting the t1/2 life of the interaction. Accordingly, we have provided a molecular basis for understanding how modifications in AGLs can result in striking alterations in the cellular response of NKT cells.
doi:10.1016/j.immuni.2011.02.001
PMCID: PMC3064745  PMID: 21376639
6.  Multiple, Unilateral Lisch Nodules in the Absence of Other Manifestations of Neurofibromatosis Type 1 
Lisch nodules associated with Neurofibromatosis Type 1 (NF1) are usually multiple and bilateral in nature. Here, we report a 21-year-old healthy, Caucasian female who was diagnosed with multiple, unilateral Lisch nodules during routine eye examination. A thorough history and physical examination revealed no other signs of NF1. We diagnosed the rare occurrence of numerous, unilateral Lisch nodules in the absence of additional features of NF1 in our patient and provide a discussion concerning the differential diagnosis of Lisch nodules as well as the potential genetic explanation of this finding.
doi:10.1155/2011/854784
PMCID: PMC3350217  PMID: 22606479
7.  The roles of community pharmacists in cardiovascular disease prevention and management 
The Australasian Medical Journal  2011;4(5):266-272.
There is ample evidence in the international literature for pharmacist involvement in the prevention and management of cardiovascular disease (CVD) conditions in primary care. Systematic reviews and meta-analyses have confirmed the significant clinical benefits of pharmacist interventions for a range of CVD conditions and risk factors. Evidence generated in research studies of Australian community pharmacist involvement in CVD prevention and management is summarised in this article.
Commonwealth funding through the Community Pharmacy Agreements has facilitated research to establish the feasibility and effectiveness of new models of primary care involving community pharmacists. Australian community pharmacists have been shown to effect positive clinical, humanistic and economic outcomes in patients with CVD conditions. Improvements in blood pressure, lipid levels, medication adherence and CVD risk have been demonstrated using different study designs. Satisfaction for GPs, pharmacists and consumers has also been reported. Perceived ‘turf‘ encroachment, expertise of the pharmacist, space, time and remuneration are challenges to the implementation of disease management services involving community pharmacists.
doi:10.4066/AMJ.2011.698
PMCID: PMC3562935  PMID: 23393519
Cardiovascular; community pharmacy; outcomes; pharmacist; primary care
8.  Stress, song and survival in sparrows 
Biology Letters  2009;5(6):746-748.
The stress response—increases in circulating glucocorticoids following a stressor—is typically considered adaptive, but few studies address the fitness consequences of individual variation in stress response. Generally, due to negative consequences of prolonged elevation of glucocorticoids, animals should have a transient stress response just sufficient to cope with the stressor. In rodents, stress responsiveness is affected by early developmental experience, and hyper-responsiveness to stress is linked to morbidity and mortality. We assessed individual variation in stress responses in free-living song sparrows, Melospiza melodia, in relation to fitness-related measures including song and overwinter survival. Birds with greater increases in corticosterone 30 min following restraint stress were less likely to return to breed the following year. Stress responsiveness was also correlated with song complexity: males with fewer syllables in their song repertoires had greater stress reactivity. Our findings support the hypothesis that developmental stressors both impair song development and affect the adult stress response. Thus, individual variation in the stress response may relate to variation in fitness.
doi:10.1098/rsbl.2009.0382
PMCID: PMC2827981  PMID: 19605381
birdsong; stress response; survival
9.  T cell receptor CDR2β and CDR3β loops collaborate functionally to shape the iNKT cell repertoire 
Immunity  2009;31(1):60-71.
SUMMARY
Mouse iNKT cell receptors (iNKT TCRs) use a single Vα14-Jα18 sequence and Vβs that are almost always Vβ8.2, Vβ7 or Vβ2, although the basis of this differential usage is unclear. We show that the Vβ bias occurs as a consequence of the CDR2β loops determining the affinity of the iNKT TCR for CD1d/glycolipids, thus controlling positive selection. Within a conserved iNKT-TCR-CD1d docking framework, these inherent Vβ-CD1d affinities are further modulated by the hypervariable CDR3β loop, thereby defining a functional interplay between the two iNKT TCR CDRβ loops. These Vβ biases reveal a broadly hierarchical response in which Vβ8.2 > Vβ7 > Vβ2 in the recognition of diverse CD1d ligands. This restriction of the iNKT TCR Vβ repertoire during thymic selection paradoxically ensures that each peripheral iNKT cell recognizes a similar spectrum of antigens.
doi:10.1016/j.immuni.2009.05.010
PMCID: PMC2965025  PMID: 19592274
10.  Synthesis and evaluation of 3”- and 4”-deoxy and -fluoro analogs of the immunostimulatory glycolipid, KRN7000 
Four 3”- and 4”-deoxy and -fluorogalactosyl ceramides were synthesized, and their ability to stimulate iNKT cells, based on levels of IL-2 production, was assessed in three NKT cell receptor hybridomas. In two of the hybridomas, 1.2 and 2H4, all of the analogs were immunostimulatory, while in the 1.4 hybridoma only the 4”-fluoro analog led to the production of significant levels of IL-2.
doi:10.1016/j.bmcl.2009.06.005
PMCID: PMC2710405  PMID: 19535248
11.  Instruction, Teacher–Student Relations, and Math Achievement Trajectories in Elementary School 
Journal of educational psychology  2010;102(2):407-417.
Children enter elementary school with widely different skill levels in core subjects. Whether because of differences in aptitude or in preparedness, these initial skill differences often translate into systematic disparities in achievement over time. How can teachers reduce these disparities? Three possibilities are to offer basic skills training, to expose students to higher order instruction, or to provide socioemotional support. Repeated measures analyses of longitudinal data from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Study of Early Child Care and Youth Development revealed that children with low, average, or high math skills prior to elementary school followed different but parallel trajectories of math achievement up through fifth grade. When enrolled in classes with inference-based instruction, however, the initially least skilled children narrowed the achievement gap as long as they did not have conflictual relations with their teachers. They did not make this kind of progress if they were in classes focused exclusively on basic skills instruction or if they were in inference-focused classes but had conflictual relations with teachers.
doi:10.1037/a0017762
PMCID: PMC2908253  PMID: 20657743
elementary school; instruction; teacher–student relations; math
12.  Admission pattern and outcome in a UK weaning centre 
Critical Care  2010;14(Suppl 1):P416.
doi:10.1186/cc8648
PMCID: PMC2934416
13.  MRI as a Biomarker of Disease Progression in a Therapeutic Trial of Milameline for AD 
Neurology  2003;60(2):253-260.
Objective
To assess the feasibility of using magnetic resonance imaging (MRI) measurements as a surrogate end point for disease progression in a therapeutic trial for Alzheimer's disease (AD).
Methods
Three-hundred-sixty-two patients with probable AD from 38 different centers participated in the MRI portion of a 52 week randomized placebo controlled trial of milameline, a muscarinic receptor agonist. The therapeutic trial itself was not completed due to projected lack of efficacy on interim analysis; however, the MRI arm of the study was continued. Of the 362 subjects who underwent a baseline MRI study, 192 subjects underwent a second MRI one-year later. Hippocampal volume and temporal horn volume were measured from the MRI scans.
Results
The annualized percent change in hippocampal volume (−4.9%) and temporal horn volume (16.1%) in the study patients were consistent with data from prior single site studies. Correlations between the rate of MRI volumetric change and change in behavioral/cognitive measures were greater for the temporal horn than for the hippocampus. Decline over time was more consistently seen with imaging measures, 99% of the time for the hippocampus, than behavioral/cognitive measures (p<0.001). Greater consistency in MRI than behavioral/clinical measures resulted in markedly lower estimated sample size requirements for clinical trials. The estimated number of subjects per arm required to detect a 50% reduction in the rate of decline over one year are: ADAS-Cog 320; MMSE 241; hippocampal volume 21; temporal horn volume fifty-four.
Conclusion
The consistency of MRI measurements obtained across sites, and the consistency between the multi-site milameline data and that obtained in prior single site studies, demonstrate the technical feasibility of using structural MRI measures as a surrogate end point of disease progression in therapeutic trials. However, validation of imaging as a biomarker of therapeutic efficacy in AD still awaits a positive trial.
PMCID: PMC2745302  PMID: 12552040
14.  Exercise effects on cardiac size and left ventricular diastolic function: relationships to changes in fitness, fatness, blood pressure and insulin resistance 
Heart  2005;92(7):893-898.
Objectives
To determine exercise training effects on cardiac size and left ventricular (LV) diastolic function and relationships of exercise induced changes in physiological and body composition parameters with cardiac parameters.
Design
Prospective, randomised controlled trial.
Subjects
Men and women (63.6 (5.7) years, body mass index 29.5 (4.4) kg/m2) with untreated hypertension (systolic blood pressure (BP) 130–159 or diastolic BP 85–99 mm Hg).
Main outcome measures
Cardiac size and LV diastolic function, peak oxygen uptake (Vo2), muscle strength, general and abdominal fatness, and insulin resistance.
Interventions
6 months of exercise training versus usual care.
Results
When analysed by group at six months, cardiac size and LV diastolic function did not differ between exercisers (n  =  51) and controls (n  =  53), whereas exercisers had significantly higher peak Vo2 (28 v 24 ml/kg/min) and strength (383 v 329 kg), and lower fatness (34% v 37%), diastolic BP (73 v 75 mm Hg) and insulin resistance (quantitative insulin sensitivity check index 0.35 v 0.34) versus controls (all p ⩽ 0.05). By regression analysis, among six month changes, increased peak Vo2 and reduced abdominal fat were associated with increased cardiac size. Increased peak Vo2 and reduced abdominal fat, BP and insulin resistance were associated with improved LV diastolic function. r Values ranged from 0.20 to 0.32 (p ⩽ 0.05).
Conclusions
When examined by group assignment, exercise had no effect on cardiac size or LV diastolic function. When individual variations in six month changes were examined, participants attaining the greatest increases in fitness and reductions in abdominal fatness, insulin resistance and BP showed a modest trend towards physiological hypertrophy characterised by increased cardiac size and improved LV diastolic function. These results suggest that decreased abdominal fatness may have a role in improving cardiovascular health.
doi:10.1136/hrt.2005.079962
PMCID: PMC1860691  PMID: 16308413
exercise; blood pressure; obesity; diastole; cardiac structure
15.  Natural Sphingomonas Glycolipids Vary Greatly in their Ability to Activate Natural Killer T Cells 
Chemistry & biology  2008;15(7):654-664.
Summary
Mouse natural killer T (NKT) cells expressing an invariant T cell antigen receptor (TCR) recognize glycosphingolipids (GSLs) from Sphingomonas bacteria. The synthetic antigens previously tested, however, were designed to closely resemble the potent synthetic agonist α-galactosyl ceramide (αGalCer), which contains a monosaccharide and a C18:0 sphingosine lipid. Some Sphingomonas bacteria, however, also have oligosaccharide containing GSLs, and they normally synthesize several GSLs with different sphingosine chains, including one with a cyclopropyl ring containing C21:0 (C21cycl) sphingosine. Here we studied the stimulation of NKT cells with synthetic GSL antigens containing natural tetrasaccharide sugars, or the C21cyclo sphingosine. Our results indicate that there is great degree of variability of the antigenic potency of different natural Sphingomonas glycolipids, with the (C21cycl) sphingosine having intermediate potency, and the oligosaccharide-containing antigens exhibiting limited or no stimulatory capacity.
doi:10.1016/j.chembiol.2008.05.012
PMCID: PMC2519143  PMID: 18635002
16.  Contact burns from hair straighteners: a new hazard in the home 
This series highlights a previously unreported hazard for children within the home, hair straightening irons. Thermal injury is a common reason for presentation at the emergency department. Contact burns from domestic irons and hair curling tongs are well documented in the literature. We have become aware of this new hazard in the home, which has resulted in several presentations to our department with deep partial thickness or full thickness burns.
doi:10.1136/emj.2005.027094
PMCID: PMC2464438  PMID: 16498145
burns; hair straighteners; children
17.  A minimal binding footprint on CD1d-glycolipid is a basis for selection of the unique human NKT TCR 
Although it has been established how CD1 binds a variety of lipid antigens (Ag), data are only now emerging that show how αβ T cell receptors (TCRs) interact with CD1-Ag. Using the structure of the human semiinvariant NKT TCR–CD1d–α-galactosylceramide (α-GalCer) complex as a guide, we undertook an alanine scanning mutagenesis approach to define the energetic basis of this interaction between the NKT TCR and CD1d. Moreover, we explored how analogues of α-GalCer affected this interaction. The data revealed that an identical energetic footprint underpinned the human and mouse NKT TCR–CD1d–α-GalCer cross-reactivity. Some, but not all, of the contact residues within the Jα18-encoded invariant CDR3α loop and Vβ11-encoded CDR2β loop were critical for recognizing CD1d. The residues within the Vα24-encoded CDR1α and CDR3α loops that contacted the glycolipid Ag played a smaller energetic role compared with the NKT TCR residues that contacted CD1d. Collectively, our data reveal that the region distant to the protruding Ag and directly above the F′ pocket of CD1d was the principal factor in the interaction with the NKT TCR. Accordingly, although the structural footprint at the NKT TCR–CD1d–α-GalCer is small, the energetic footprint is smaller still, and reveals the minimal requirements for CD1d restriction.
doi:10.1084/jem.20072141
PMCID: PMC2292230  PMID: 18378792
18.  In Vitro Study of Flow Regulation for Pulmonary Insufficiency 
Given the tolerance of the right heart circulation to mild regurgitation and gradient, we study the potential of using motionless devices to regulate the pulmonary circulation. In addition, we document the flow performance of two mechanical valves. A motionless diode, a nozzle, a mechanical bileaflet valve, and a tilting disk valve were tested in a pulmonary mock circulatory system over the normal human range of pulmonary vascular resistance (PVR). For the mechanical valves, regurgitant fractions (RFs) and transvalvular pressure gradients were found to be weak functions of PVR. On the low end of normal PVR, the bileaflet and tilting disk valves fluttered and would not fully close. Despite this anomaly, the regurgitant fraction of either valve did not change significantly. The values for RF and transvalvular gradient measured varied from 4 to 7% and 4 to 7 mm Hg, respectively, at 5 lpm for all tests. The diode valve was able to regulate flow with mild regurgitant fraction and trivial gradient but with values higher than either mechanical valve tested. Regurgitant fraction ranged from 2 to 17% in tests extending from PVR values of 1 to 4.5 mm Hg/lpm at 5 lpm and with concomitant increases in gradient up to 17 mm Hg. The regurgitant fraction for the nozzle increased from 2 to 23% over the range of PVR with gradients increasing to 18 mm Hg. The significant findings were: (1) the mechanical valves controlled regurgitation at normal physiological cardiac output and PVR even though they failed to close at some normal values of PVR and showed leaflet flutter; and (2) it may be possible to regulate the pulmonary circulation to tolerable levels using a motionless pulmonary valve device.
doi:10.1115/1.2540892
PMCID: PMC2140231  PMID: 17408334
mechanical heart valve; pulmonary vascular resistance; diode; regurgitant fraction
19.  Exercise training: can it improve cardiovascular health in patients with type 2 diabetes? 
doi:10.1136/bjsm.2004.012187
PMCID: PMC1724815  PMID: 15155419
21.  Cultural aspects of cancer genetics: setting a research agenda 
Journal of Medical Genetics  2001;38(7):425-429.
BACKGROUND—Anecdotal evidence suggests that people from non-Anglo-Celtic backgrounds are under-represented at familial cancer clinics in the UK, the USA, and Australia. This article discusses cultural beliefs as a potential key barrier to access, reviews previous empirical research on cultural aspects of cancer genetics, draws implications from findings, and sets a research agenda on the inter-relationships between culture, cancer genetics, and kinship.
METHODS—The CD-ROM databases MEDLINE, PsychLIT, CINAHL, and Sociological Abstracts were searched from 1980 onwards.
RESULTS—Cultural aspects of cancer genetics is the focus of an emerging body of publications. Almost all studies assessed African-American women with a family history of breast cancer and few studies included more diverse samples, such as Americans of Ashkenazi Jewish background or Hawaiian- and Japanese-Americans. Our analysis of published reports suggests several directions for future research. First, an increased focus on various Asian societies appears warranted. Research outside North America could explore the extent to which findings can be replicated in other multicultural settings. In addition, control group designs are likely to benefit from systematically assessing culture based beliefs and cultural identity in the "majority culture" group used for comparative purposes.
CONCLUSION—More data on which to base the provision of culturally appropriate familial cancer clinic services to ethnically diverse societies are needed. Empirical data will assist with culturally appropriate categorisation of people from other cultures into risk groups based on their family histories and provide the basis for the development of culturally appropriate patient education strategies and materials.


Keywords: hereditary cancer; kinship; culture; family history; cultural competence
doi:10.1136/jmg.38.7.425
PMCID: PMC1757175  PMID: 11432959
22.  The quality and isolation of habitat patches both determine where butterflies persist in fragmented landscapes. 
Habitat quality and metapopulation effects are the main hypotheses that currently explain the disproportionate decline of insects in cultivated Holarctic landscapes. The former assumes a degradation in habitat quality for insects within surviving ecosystems, the latter that too few, small or isolated islands of ecosystem remain in landscapes for populations to persist. These hypotheses are often treated as alternatives, and this can lead to serious conflict in the interpretations of conservationists. We present the first empirical demonstration that habitat quality and site isolation are both important determinants of where populations persist in modern landscapes. We described the precise habitat requirements of Melitaea cinxia, Polyommatus bellargus and Thymelicus acteon, and quantified the variation in carrying capacity within each butterfly's niche. We then made detailed surveys to compare the distribution and density of every population of each species with the size, distance apart and quality of their specific habitats in all their potential habitat patches in three UK landscapes. In each case, within-site variation in habitat quality explained which patches supported a species' population two to three times better than site isolation. Site area and occupancy were not correlated in any species. Instead of representing alternative paradigms, habitat quality and spatial effects operate at different hierarchical levels within the same process: habitat quality is the missing third parameter in metapopulation dynamics, contributing more to species persistence, on the basis of these results, than site area or isolation. A reorientation in conservation priorities is recommended.
doi:10.1098/rspb.2001.1693
PMCID: PMC1088810  PMID: 11522197
23.  Preventing impaired driving around the world: lessons learned 
Injury Prevention  2000;6(2):80-81.
doi:10.1136/ip.6.2.80
PMCID: PMC1730620  PMID: 10875660
24.  Regulation of AE2-mediated Cl− Transport by Intracellular or by Extracellular pH Requires Highly Conserved Amino Acid Residues of the AE2 NH2-terminal Cytoplasmic Domain 
The Journal of General Physiology  2002;120(5):707-722.
We reported recently that regulation by intracellular pH (pHi) of the murine Cl−/HCO3− exchanger AE2 requires amino acid residues 310–347 of the polypeptide's NH2-terminal cytoplasmic domain. We have now identified individual amino acid residues within this region whose integrity is required for regulation of AE2 by pH. 36Cl− efflux from AE2-expressing Xenopus oocytes was monitored during variation of extracellular pH (pHo) with unclamped or clamped pHi, or during variation of pHi at constant pHo. Wild-type AE2–mediated 36Cl− efflux was profoundly inhibited by acid pHo, with a value of pHo(50) = 6.87 ± 0.05, and was stimulated up to 10-fold by the intracellular alkalinization produced by bath removal of the preequilibrated weak acid, butyrate. Systematic hexa-alanine [(A)6]bloc substitutions between aa 312–347 identified the greatest acid shift in pHo(50) value, ∼0.8 pH units in the mutant (A)6342–347, but only a modest acid-shift in the mutant (A)6336–341. Two of the six (A)6 mutants retained normal pHi sensitivity of 36Cl− efflux, whereas the (A)6 mutants 318–323, 336–341, and 342–347 were not stimulated by intracellular alkalinization. We further evaluated the highly conserved region between aa 336–347 by alanine scan and other mutagenesis of single residues. Significant changes in AE2 sensitivity to pHo and to pHi were found independently and in concert. The E346A mutation acid-shifted the pHo(50) value to the same extent whether pHi was unclamped or held constant during variation of pHo. Alanine substitution of the corresponding glutamate residues in the cytoplasmic domains of related AE anion exchanger polypeptides confirmed the general importance of these residues in regulation of anion exchange by pH. Conserved, individual amino acid residues of the AE2 cytoplasmic domain contribute to independent regulation of anion exchange activity by pHo as well as pHi.
doi:10.1085/jgp.20028641
PMCID: PMC2229549  PMID: 12407081
Cl−/HCO3− exchange; weak acids; Xenopus oocytes; isotopic flux; pH-sensitive microelectrodes
25.  Advance directives and living wills. 
Postgraduate Medical Journal  1998;74(869):151-156.
Under certain circumstances, living wills or advance directives may carry legal force in the UK. This paper traces the development of advance directives, clarifies their current legal position and discusses potential problems with their use. Case histories are used to illustrate some of the common dilemmas which doctors may face.
PMCID: PMC2360827  PMID: 9640440

Results 1-25 (59)