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1.
Inflamm Bowel Dis ; 28(12): 1859-1864, 2022 12 01.
Article de Anglais | MEDLINE | ID: mdl-35259266

RÉSUMÉ

BACKGROUND: Exclusive enteral nutrition (EEN) is the recommended induction treatment of mild to moderate active pediatric Crohn's disease (CD). This study compared outcomes of 2 proprietary polymeric formulas. Treatment effectiveness was examined along with practical aspects of formula delivery and differences in estimated treatment costs. METHODS: Data were retrospectively collected from patients with CD who received a generic oral nutritional supplement (Fortisip) across 2 centers (RCH, Melbourne and RHSC, Edinburgh). This was compared with a prospective cohort (RHC, Glasgow) that used a specialized formula (Modulen IBD). The data collected included patient demographics, remission rates, biochemical markers, administration method, and anthropometrics. The estimated treatment cost was performed by comparing price per kcal between each formula. RESULTS: One hundred seventy-one patients were included (106 Fortisip, 65 Modulen IBD, 70 female; median age 13.3 yrs). No difference was demonstrated in remission rate (Fortisip n = 67 of 106 [63%] vs Modulen IBD n = 41 of 64 [64%], P = .89), nonadherence rate (Fortisip n = 7 of 106 [7%] vs Modulen IBD 3 of 64 [5%], P = .57) or method of administration (NGT Fortisip use n = 16 of 106 [12%] vs Modulen IBD 14 of 65 [22%]; P = .31). There was no difference in reduction of biochemical disease markers between the groups (C-reactive protein , P = .13; erythrocyte sedimentation rate, P = .49; fecal calprotectin, P = .94). However, there was a cost-saving of around £500/patient/course if the generic oral nutritional supplement was used. CONCLUSIONS: The generic oral nutritional supplement and specialized formulas both had similar clinical effectiveness in induction of remission in pediatric CD. However, there is considerable cost-saving when using a generic oral nutritional supplement.


Sujet(s)
Maladie de Crohn , Enfant , Humains , Femelle , Adolescent , Induction de rémission , Études rétrospectives , Études prospectives , Maladie de Crohn/traitement médicamenteux , Résultat thérapeutique , Marqueurs biologiques
4.
Proc Biol Sci ; 285(1883)2018 07 18.
Article de Anglais | MEDLINE | ID: mdl-30051845

RÉSUMÉ

To withstand the pressures of a rapidly changing world, resilient ecosystems should exhibit compensatory dynamics, including uncorrelated temporal shifts in population sizes. The observation that diversity is maintained through time in many systems is evidence that communities are indeed regulated and stabilized, yet empirical observations suggest that positive covariance in species abundances is widespread. This paradox could be resolved if communities are composed of a number of ecologically relevant sub-units in which the members compete for resources, but whose abundances fluctuate independently. Such modular organization could explain community regulation, even when the community as a whole appears synchronized. To test this hypothesis, we quantified temporal synchronicity in annual population abundances within spatial guilds in an estuarine fish assemblage that has been monitored for 36 years. We detected independent fluctuations in annual abundances within guilds. By contrast, the assemblage as a whole exhibited temporal synchronicity-an outcome linked to the dynamics of guild dominants, which were synchronized with each other. These findings underline the importance of modularity in explaining community regulation and highlight the need to protect assemblage composition and structure as well as species richness.


Sujet(s)
Biote , Poissons/physiologie , Animaux , Angleterre , Estuaires , Densité de population , Dynamique des populations , Saisons
5.
Sci Total Environ ; 637-638: 1175-1186, 2018 Oct 01.
Article de Anglais | MEDLINE | ID: mdl-29801211

RÉSUMÉ

Mercury inputs by surface and ground water sources to Penobscot River from a defunct Hg-cell chlor-alkali plant were measured in 2009-10 and estimated for the entire period of operation of this facility. Over the measured interval (422 days) approximately 2.3 kg (5.4 g day-1) of mercury was discharged to the Penobscot River by the two surface streams that drain the site, with most of the combined loading (1.8 kg Hg, 78%) associated with a single storm with rainfall in excess of 100 mm. Groundwater seepage rates from the site, as estimated from both a radon tracer and seepage meter methods were in the range of 3 to 4 cm day-1 and, when combined with a best estimate of the area of groundwater discharge (11,000 m2) and average seepage/porewater mercury concentration (242 ng L-1, UCL95), yielded a loading of 0.11 g day-1 for site groundwater. None of the municipal or other industrial point sources of mercury to the river between Veazie and Bucksport, Maine exceeded 1 g day-1 individually, nor was the aggregate loading of all such sources >3 g day-1 (based on State of Maine data). Mercury loadings for the three largest tributaries downstream of Veazie Dam were estimated to contribute 4.2, 3.7 and 2.5 g day-1, respectively, to the Penobscot River. Based on sampling (total Hg ~ 2 to 4 ng L-1) and historical mean discharge data (340-460 m3 s-1), the Penobscot River upstream of the plant site contributes as much as 160 g day-1 to the downstream reach depending on river discharge. Estimates of historical (1967-2012) mercury loading using both generic emission factors and measured releases ranged from 2.6 to 27 MT while the mass of mercury found in downstream sediments amounted to 9 MT.


Sujet(s)
Surveillance de l'environnement , Mercure/analyse , Polluants chimiques de l'eau/analyse , Pollution chimique de l'eau/statistiques et données numériques , Alcalis , Sédiments géologiques , Maine , Rivières/composition chimique
6.
Chem Commun (Camb) ; 54(27): 3383-3386, 2018 Mar 29.
Article de Anglais | MEDLINE | ID: mdl-29552681

RÉSUMÉ

The spontaneous formation of a chiral phase via molecular recognition in a system consisting of achiral components is reported. Specifically, the liquid crystalline behaviour of two molecular complexes assembled by hydrogen bonding between a stilbazole-based template and alkoxybenzoic acids has been characterised. The complexes exhibit the heliconical twist-bend nematic phase (NTB) over a broad temperature range despite the hydrogen-bond acceptor not being liquid crystalline and the donor exhibiting the conventional achiral nematic phase.

12.
Mar Pollut Bull ; 61(1-3): 100-14, 2010.
Article de Anglais | MEDLINE | ID: mdl-20074757

RÉSUMÉ

The species of fish and macro-crustacean living within the Severn Estuary are reviewed. The fish community is notably species rich and exceeds 100 species in total for the estuary. Standardised long-term sampling at Hinkley Point in Bridgwater Bay gives a total complement of 83 for a single locality and this number is increasing by about one new species every two years. Most of these new species are moving in from centres of population lying to the south of the estuary. Almost all species of fish and macro-crustacean living within the estuary undertake regular migrations so that they tend to move seasonally in waves up and down the estuary. For fish, both species richness and the total abundance reach a maximum in late summer and autumn. The timing of this peak varies between the upper and lower estuary. This seasonal maximum is primarily caused by the arrival of the new recruits which use the estuary as a nursery. In contrast, crustaceans tend to be at their most diverse and abundant in early to mid summer. Using a 30-year time series of fish and crustacean abundance collected at Hinkley Point it is shown that major changes in the structure of the community are now underway and there are considerable recent changes in the abundance. However, some abundant species, including sand goby, Pomatoschistus spp., whiting, Merlangius merlangus and sprat, Sprattus sprattus, the three most abundant species in the estuary, have shown no long-term trend. At present, approximately 20% of the fish and macro-crustaceans observed in Bridgwater Bay are undergoing rapid, typically exponential, change in abundance. For a numerically abundant, diverse, fauna composed of approximately 90 species such levels of change are unexpected and suggest that the system is presently far from equilibrium. In some cases, the observed changes can be related to recent warming and the North Atlantic Oscillation. The overall increase in fish abundance observed may reflect a general improvement in water quality and a reduction in other anthropogenic impacts such as mortality in cooling-water intakes. The potential impacts of tidal power generation in the Severn Estuary are reviewed. There is considerable potential for any major installation to impact the fish and crustacean populations as they migrate and also alter the nature of the habitat resulting in changes in community composition. A particular difficulty in predicting the future impact of harnessing tidal energy is that the present community is already changing rapidly. The ability of fish and crustaceans to pass through the turbines unharmed will be a key issue in an assessment of the impact of tidal power generation.


Sujet(s)
Crustacea/croissance et développement , Écosystème , Poissons/croissance et développement , Rivières , Eau de mer , Animaux , Biodiversité , Crustacea/classification , Poissons/classification , Dynamique des populations , Royaume-Uni
13.
Scott Med J ; 54(4): 11-4, 2009 Nov.
Article de Anglais | MEDLINE | ID: mdl-20034274

RÉSUMÉ

BACKGROUND AND AIMS: Familial benign hypocalciuric hypercalcaemia (FBHH) is a benign autosomal dominantly inherited condition which results in elevated serum calcium and low urinary calcium. This condition is of clinical interest because it can be mistakenly diagnosed as primary hyperparathyroidism (PHP). In most cases FBHH can be shown to be due to a mutation in the calcium sensing receptor (CASR) gene and we aimed to find the causative mutation in three Scottish kindreds with FBHH. METHODS: We used a combination of denaturing gradient gel electrophoresis and direct DNA sequencing to detect mutations in the CASR gene. RESULTS: We detected a mutation in the CASR gene in each of the three kindreds. Two different mutations were detected (the same one was present in two kindreds). Neither mutation has been reported previously. All hypercalcaemic individuals from each kindred had the appropriate mutation while all normocalcaemic individuals did not. CONCLUSION: In the vast majority of kindreds with FBHH which have been reported previously, the CASR mutation responsible is private to that kindred. In three Scottish kindreds we have identified two new mutations.


Sujet(s)
Calcium/urine , Hypercalcémie/génétique , Mutation , Récepteurs-détecteurs du calcium/génétique , Femelle , Humains , Pedigree , Écosse
14.
Biochem Soc Trans ; 33(Pt 4): 867-72, 2005 Aug.
Article de Anglais | MEDLINE | ID: mdl-16042616

RÉSUMÉ

A general strategy for the expression of bacterial membrane transport and receptor genes in Escherichia coli is described. Expression is amplified so that the encoded proteins comprise 5-35% of E. coli inner membrane protein. Depending upon their topology, proteins are produced with RGSH6 or a Strep tag at the C-terminus. These enable purification in mg quantities for crystallization and NMR studies. Examples of one nutrient uptake and one multidrug extrusion protein from Helicobacter pylori are described. This strategy is successful for membrane proteins from H. pylori, E. coli, Enterococcus faecalis, Bacillus subtilis, Staphylococcus aureus, Microbacterium liquefaciens, Brucella abortus, Brucella melitensis, Campylobacter jejuni, Neisseria meningitides, Streptomyces coelicolor and Rhodobacter sphaeroides.


Sujet(s)
Protéines de transport membranaire/métabolisme , Protéines bactériennes/composition chimique , Protéines bactériennes/génétique , Protéines bactériennes/métabolisme , Transport biologique actif , Dichroïsme circulaire , ADN bactérien/génétique , Helicobacter pylori/composition chimique , Helicobacter pylori/génétique , Helicobacter pylori/métabolisme , Protéines de transport membranaire/composition chimique , Protéines de transport membranaire/génétique , Modèles biologiques , Plasmides , Cartographie de restriction , Symporteurs/génétique , Symporteurs/métabolisme
15.
Sex Transm Infect ; 78(4): 246-9, 2002 Aug.
Article de Anglais | MEDLINE | ID: mdl-12181460

RÉSUMÉ

OBJECTIVE: To describe an exercise, the structure and content of which assists medical students to conduct potentially embarrassing conversations concerning sexual health which require expression of empathy, to integrate previous learning, to identify their further learning needs, and to develop and test strategies to meet these needs. METHOD: Students' role play, sequentially, speakers (patients) and listeners (clinical students) in a "carousel," in which all students are engaged at all times in a sequence of pairings which change at rapid intervals. Half way through the exercise, students reflect on the experience, identify difficulties and successes, and develop and share strategies for experimental use in the second half of the exercise. RESULTS: Qualitative comments from the written student evaluations are reported. CONCLUSIONS: The exercise provides a formative student centred approach to the integration and further development of previously learnt knowledge and skills of value for promoting sexual health education. It is useful for educators interested in promoting more open and informed learning about sexual health.


Sujet(s)
Communication , Empathie , Étudiant médecine , Enseignement/méthodes , Attitude envers la santé , Assistance , Enseignement médical premier cycle/méthodes , Émotions , Humains , Relations entre professionnels de santé et patients , Jeu de rôle , Éducation sexuelle , Étudiant médecine/psychologie , Royaume-Uni
16.
Int J Food Microbiol ; 76(1-2): 151-64, 2002 Jun 05.
Article de Anglais | MEDLINE | ID: mdl-12038572

RÉSUMÉ

Salmonella and Campylobacter continue to be major foodborne pathogens and raw poultry is considered to be an important source of these bacteria. In this study, the prevalence and numbers of Salmonella and Campylobacter spp. in relation to isolation/sampling methods were determined in 241 whole raw chickens purchased from retail outlets in England during the winters of 1998/1999 (101 chickens) and 1999/2000 (140 chickens). The packaging of the 140 chickens was also examined for the presence of the above pathogens. The prevalence and numbers of enterococci were examined in 21 of the 101 chickens. In total, Salmonella and Campylobacter spp. were present in 25% and 83% of the chickens, respectively. Salmonella were isolated from a sample representing both the inside and outside of the packaging in 19% of the chickens, while the corresponding figure for Campylobacter spp. was 56%. Both of these pathogens were isolated from the outside of the packaging in 6% of the chickens. Salmonella was more frequently isolated from samples containing chicken skin in comparison with those containing carcass-rinse fluid only. Two chickens (0.8%) were positive for Salmonella by direct enumeration methods with contamination levels of log10 3.8 and 4.5 colony forming units (cfu) per carcass, respectively. The most prevalent serotypes were S. Hadar, S. Enteritidis and S. Indiana and two different serotypes were identified in 5/20 salmonella-positive chickens. Resistance to at least one antibiotic was found in 70% of the strains, 46% were multiresistant (resistant to > or = four drugs) and 52% showed a lowered susceptibility to ciprofloxacin. The likelihood of isolating Campylobacter spp. from neck-skin, carcass-rinse or carcass-rinse plus whole skin samples was similar, Campylobacter spp. were found in higher levels in carcass-rinse or carcass-rinse plus whole skin samples than in neck-skin. The log10 cfu of Campylobacter spp. were 2.70-4.99 in 18% of the chickens and 5.00-6.99 in 20%. Campylobacter isolates (425) comprised Campylobacter jejuni (98%) and C. coli (2%) and 98 different sero/phagetypes of these two species were identified. Resistance to at least one antibiotic was found in 73% of the strains and 13% were multiresistant. Thirteen percent of the strains showed lowered susceptibility to ciprofloxacin, while 4.9% were resistant to erythromycin. Vancomycin-resistant enterococci (VRE), able to grow on agar containing 15 mg l(-1) vancomycin (VRE15), were present in 19 chickens. The log10 cfu of VRE15 was 2.90-3.99 in 10 chickens and between 4.00 and 4.99 in two chickens. The data presented here contribute to risk assessment and highlight the need to continue to emphasise the safe handling of raw retail poultry.


Sujet(s)
Campylobacter/isolement et purification , Poulets/microbiologie , Contamination des aliments/analyse , Salmonella/isolement et purification , Animaux , Campylobacter/effets des médicaments et des substances chimiques , Campylobacter/croissance et développement , Numération de colonies microbiennes , Sécurité des produits de consommation , Multirésistance bactérienne aux médicaments , Angleterre , Manipulation des aliments , Microbiologie alimentaire , Emballage alimentaire , Prévalence , Salmonella/effets des médicaments et des substances chimiques , Salmonella/croissance et développement , Sérotypie , Peau/microbiologie
17.
Circulation ; 104(11): 1255-60, 2001 Sep 11.
Article de Anglais | MEDLINE | ID: mdl-11551876

RÉSUMÉ

BACKGROUND: Insulin resistance (IR) and hyperinsulinemia are phenotypically associated with hypertension. We have previously provided evidence that blood pressure (BP) and IR cosegregate in Hispanic families, suggesting that this association has a genetic component. In the present study, we provide further support for the hypothesis of a genetic basis for the BP-IR relationship from a genetic linkage study. METHODS AND RESULTS: A 10-cM genome scan was conducted in 390 Hispanic family members of 77 hypertensive probands. Detailed measurements of BP, glucose, insulin levels, and insulin sensitivity (euglycemic clamp) were performed in adult offspring of probands. Multipoint variance component linkage analysis was used. A region on chromosome 7q seemed to influence both IR and BP. The greatest evidence for linkage was found for fasting insulin (lod score=3.36 at 128 cM), followed by systolic BP (lod score=2.06 at 120 cM). Fine mapping with greater marker density in this region increased the maximum lod score for fasting insulin to 3.94 at 125 cM (P=0.00002); lod score for systolic BP was 2.51 at 112 cM. Coincident mapping at this locus also included insulin sensitivity measured by the homeostasis assessment model (HOMA) and serum leptin concentrations. Insulin sensitivity by euglycemic clamp did not map to the same locus. CONCLUSIONS: Our results demonstrate that a major gene determining fasting insulin is located on chromosome 7q. Linkage of BP, HOMA, and leptin levels to the same region suggests this locus may broadly influence traits associated with IR and supports a genetic basis for phenotypic associations in IR syndrome.


Sujet(s)
Pression sanguine/génétique , Chromosomes humains de la paire 7/génétique , Hypertension artérielle/génétique , Insulinorésistance/génétique , Adolescent , Adulte , Cartographie chromosomique , Santé de la famille , Jeûne , Femelle , Liaison génétique , Génome humain , Hispanique ou Latino/génétique , Humains , Insuline/sang , Mâle , Répétitions microsatellites , Adulte d'âge moyen , Phénotype
18.
Gerontologist ; 41(4): 490-8, 2001 Aug.
Article de Anglais | MEDLINE | ID: mdl-11490047

RÉSUMÉ

PURPOSE: This study examined gender differences in cardiovascular responses to laboratory-based stress, as well as in ambulatory hemodynamic (i.e., blood pressure and heart rate) functioning among caregivers of persons with dementia. DESIGN & METHODS: Participants were 25 men and 25 women caregivers, matched on age, type of care recipient's dementia, and relationship to the care recipient. After cardiovascular reactivity to a laboratory-based caregiving stressor was assessed, the ambulatory hemodynamic functioning levels of caregivers were measured in caregivers' natural environments. RESULTS: Female caregivers displayed greater systolic and diastolic blood pressure reactivity to a laboratory-based stress task (i.e., discussing caregiving difficulties) compared with male caregivers (p < or =.01). In contrast, no gender differences were found for ambulatory hemodynamic functioning when aggregated overall or when in the presence of the care recipient. IMPLICATIONS: Laboratory-based findings suggest that female caregivers experience greater blood pressure reactivity to caregiving-related stress than do male caregivers. However, these laboratory-based gender differences may not generalize to differences in hemodynamic functioning in caregivers' daily lives.


Sujet(s)
Maladie d'Alzheimer/psychologie , Éveil , Pression sanguine , Aidants/psychologie , Rythme cardiaque , Stress psychologique/complications , Sujet âgé , Sujet âgé de 80 ans ou plus , Femelle , Humains , Mâle , Adulte d'âge moyen , Surveillance électronique ambulatoire , Facteurs sexuels
19.
Biochemistry ; 40(22): 6653-9, 2001 Jun 05.
Article de Anglais | MEDLINE | ID: mdl-11380260

RÉSUMÉ

The human endonuclease III homologue (hNTH1) removes premutagenic cytosine damage from DNA. This includes 5-hydroxycytosine, which has increased potential for pairing with adenine, resulting in C --> T transition mutations. Here we report that hNTH1 acts on both 5-hydroxycytosine and abasic sites preferentially when these are situated opposite guanines in DNA. Discrimination against other opposite bases is strongly dependent on the presence of magnesium. To further elucidate this effect, we have introduced mutations in the helix-hairpin-helix domain of hNTH1 (K212S, P211R, +G212, and DeltaP211), and measured the kinetics of 5-hydroxycytosine removal of the mutants relative to wild type. The K212S and DeltaP211 (truncated hairpin) mutant proteins were both inactive, whereas the extended hairpin in the +G212 mutant diminished recognition and binding to 5-hydroxycytosine-containing DNA. The P211R mutant resembled native hNTH1, except for decreased specificity of binding. Despite the altered kinetic parameters, the active mutants retained the ability to discriminate against the pairing base, indicating that enzyme interactions with the opposite strand relies on other domains than the active site helix-hairpin-helix motif.


Sujet(s)
Cytosine/analogues et dérivés , Altération de l'ADN , Réparation de l'ADN , ADN/composition chimique , Deoxyribonuclease (pyrimidine dimer) , Endodeoxyribonucleases/composition chimique , Protéines Escherichia coli , Guanine/composition chimique , Séquence d'acides aminés , Mésappariement de bases , Substances tampon , Carbon-oxygen lyases/composition chimique , Carbon-oxygen lyases/métabolisme , Cytosine/composition chimique , ADN/métabolisme , DNA-(apurinic or apyrimidinic site) lyase , DNA-formamidopyrimidine glycosylase , Deoxyribonuclease IV (phage T4-induced) , Endodeoxyribonucleases/génétique , Endodeoxyribonucleases/métabolisme , Guanine/métabolisme , Motifs à hélice-tour-hélice/génétique , Humains , Cinétique , Données de séquences moléculaires , N-Glycosyl hydrolases/génétique , N-Glycosyl hydrolases/métabolisme , Similitude de séquences d'acides nucléiques , Spécificité du substrat/génétique
20.
Biochim Biophys Acta ; 1510(1-2): 464-73, 2001 Feb 09.
Article de Anglais | MEDLINE | ID: mdl-11342180

RÉSUMÉ

The D-galactose-H(+) symport protein (GalP) of Escherichia coli is a homologue of the human glucose transport protein, GLUT1. After amplified expression of the GalP transporter in E. coli, other membrane proteins were prereacted with N-ethylmaleimide in the presence of excess D-galactose to protect GalP. Inner membranes were then specifically spin labelled on Cys(374) of GalP with 4-maleimide-2,2,6,6-tetramethylpiperidine-1-oxyl. The electron paramagnetic resonance (EPR) spectra are characteristic of a single labelling site in which the mobility of the spin label is very highly constrained. This is confirmed with other nitroxyl spin labels, which are derivatives of iodoacetamide and indanedione. Saturation transfer EPR spectra indicate that the overall rotation of the GalP protein in the membrane is slow at low temperatures (approx. 2 degrees C), but considerably more rapid and highly anisotropic at physiological temperatures. The rate of rotation about the membrane normal at 37 degrees C is consistent with predictions for a 12-transmembrane helix assembly that is less than closely packed.


Sujet(s)
Protéines de liaison au calcium , Escherichia coli/génétique , Transporteurs de monosaccharides/génétique , Protéines de liaison périplasmiques , Marqueurs de spin , Séquence d'acides aminés , Sites de fixation , Membrane cellulaire/métabolisme , Diffusion , Spectroscopie de résonance de spin électronique/méthodes , Escherichia coli/métabolisme , Données de séquences moléculaires , Transporteurs de monosaccharides/biosynthèse , Transporteurs de monosaccharides/composition chimique , Plasmides , Température
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