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1.
Prehosp Emerg Care ; : 1-8, 2023 Nov 29.
Article de Anglais | MEDLINE | ID: mdl-38019685

RÉSUMÉ

OBJECTIVE: Rapid sequence intubation (RSI) is frequently performed by emergency medical services (EMS). We investigated the relationship between succinylcholine and rocuronium use and time until first laryngoscopy attempt, first-pass success, and Cormack-Lehane (CL) grades. METHODS: We included adult patients for whom prehospital RSI was attempted from July 2015 through June 2022 in a retrospective, observational study with pre-post analysis. Timing was verified using recorded defibrillator audio in addition to review of continuous ECG, pulse oximetry, and end-tidal carbon dioxide waveforms. Our primary exposure was neuromuscular blocking agent (NMBA) used, either rocuronium or succinylcholine. Our prespecified primary outcome was the first attempt Cormack-Lehane view. Key secondary outcomes were first laryngoscopy attempt success rate, timing from NMBA administration to first attempt, number of attempts, and hypoxemic events. RESULTS: Of 5,179 patients in the EMS airway registry, 1,475 adults received an NMBA while not in cardiac arrest. Cormack-Lehane grades for succinylcholine and rocuronium were similar: grade I (64%, 59% [95% CI 0.64-1.09]), grade II (16%, 21%), grade III (18%, 16%), grade IV (3%, 3%). The median interval from NMBA administration to start of the first attempt was 57 s for succinylcholine and 83 s for rocuronium (mean difference 28 [95% CI 20-36] seconds). First attempt success was 84% for succinylcholine and 83% for rocuronium. Hypoxemic events were present in 25% of succinylcholine cases and 23% of rocuronium cases. CONCLUSIONS: Prehospital use of either rocuronium or succinylcholine is associated with similar Cormack-Lehane grades, first-pass success rates, and rates of peri-intubation hypoxemia.

2.
Phys Rev Lett ; 127(16): 162501, 2021 Oct 15.
Article de Anglais | MEDLINE | ID: mdl-34723594

RÉSUMÉ

We report an improved measurement of the free neutron lifetime τ_{n} using the UCNτ apparatus at the Los Alamos Neutron Science Center. We count a total of approximately 38×10^{6} surviving ultracold neutrons (UCNs) after storing in UCNτ's magnetogravitational trap over two data acquisition campaigns in 2017 and 2018. We extract τ_{n} from three blinded, independent analyses by both pairing long and short storage time runs to find a set of replicate τ_{n} measurements and by performing a global likelihood fit to all data while self-consistently incorporating the ß-decay lifetime. Both techniques achieve consistent results and find a value τ_{n}=877.75±0.28_{stat}+0.22/-0.16_{syst} s. With this sensitivity, neutron lifetime experiments now directly address the impact of recent refinements in our understanding of the standard model for neutron decay.

3.
Sci Signal ; 13(650)2020 09 22.
Article de Anglais | MEDLINE | ID: mdl-32963012

RÉSUMÉ

A homozygous missense mutation in the gene encoding the estrogen receptor α (ERα) was previously identified in a female patient with estrogen insensitivity syndrome. We investigated the molecular features underlying the impaired transcriptional response of this mutant (ERα-Q375H) and four other missense mutations at this position designed to query alternative mechanisms. The identity of residue 375 greatly affected the sensitivity of the receptor to agonists without changing the ligand binding affinity. Instead, the mutations caused changes in the affinity of coactivator binding and alterations in the balance of coactivator and corepressor recruitment. Comparisons among the transcriptional regulatory responses of these six ERα genotypes to a set of ER agonists showed that both steric and electrostatic factors contributed to the functional deficits in gene regulatory activity of the mutant ERα proteins. ERα-coregulator peptide binding in vitro and RIME (rapid immunoprecipitation mass spectrometry of endogenous) analysis in cells showed that the degree of functional impairment paralleled changes in receptor-coregulator binding interactions. These findings uncover coupling between ligand binding and coregulator recruitment that affects the potency rather than the efficacy of the receptor response without substantially altering ligand binding affinity. This highlights a molecular mechanism for estrogen insensitivity syndrome involving mutations that perturb a bidirectional allosteric coupling between ligand binding and coregulator binding that determines receptor transcriptional output.


Sujet(s)
Récepteur alpha des oestrogènes/génétique , Oestrogènes/métabolisme , Mutation faux-sens , Coactivateur-1 de récepteur nucléaire/génétique , Coactivateur-3 de récepteur nucléaire/génétique , Sites de fixation/génétique , Résistance aux substances/génétique , Récepteur alpha des oestrogènes/composition chimique , Récepteur alpha des oestrogènes/métabolisme , Oestrogènes/pharmacologie , Régulation de l'expression des gènes , Cellules HEK293 , Cellules HepG2 , Humains , Cinétique , Ligands , Simulation de dynamique moléculaire , Coactivateur-1 de récepteur nucléaire/métabolisme , Coactivateur-3 de récepteur nucléaire/métabolisme , Liaison aux protéines , Domaines protéiques
4.
Yale J Biol Med ; 93(2): 291-305, 2020 06.
Article de Anglais | MEDLINE | ID: mdl-32607090

RÉSUMÉ

Essential oils (EOs) have risen in popularity over the past decade. These oils function in society as holistic integrative modalities to traditional medicinal treatments, where many Americans substitute EOs in place of other prescribed medications. EOs are found in a multitude of products including food flavoring, soaps, lotions, shampoos, hair styling products, cologne, laundry detergents, and even insect repellents. EOs are complex substances comprised of hundreds of components that can vary greatly in their composition depending upon the extraction process by the producer or the origin of the plant. Thus, making it difficult to determine which pathways in the body are affected. Here, we review the published research that shows the health benefits of EOs as well as some of their adverse effects. In doing so, we show that EOs, as well as some of their individual components, possess antimicrobial, antiviral, antibiotic, anti-inflammatory, and antioxidant properties as well as purported psychogenic effects such as relieving stress, treating depression, and aiding with insomnia. Not only do we show the health benefits of using EOs, but we also indicate risks associated with their use such as their endocrine disrupting properties leading to the induction of premature breast growth in young adolescents. Taken together, there are many positive and potentially negative risks to human health associated with EOs, which make it important to bring awareness to all their known effects on the human body.


Sujet(s)
Aromathérapie/méthodes , Huile essentielle , Humains , Médecine traditionnelle/méthodes , Huile essentielle/effets indésirables , Huile essentielle/pharmacologie , Appréciation des risques
7.
Lab Chip ; 20(10): 1771-1779, 2020 05 19.
Article de Anglais | MEDLINE | ID: mdl-32347869

RÉSUMÉ

Quantitative real-time PCR (qPCR) has been the standard for nucleic acid quantification as it has a large dynamic range and good sensitivity. Digital PCR is rapidly supplanting qPCR in many applications as it provides excellent quantitative precision. However, both techniques require extensive sample preparation, and highly multiplexed assays that quantify multiple targets can be difficult to design and optimize. Here we describe a new nucleic acid quantification method that we call Spatially Isolated Reactions in a Complex Array (SIRCA), a highly parallel nucleic acid preparation, amplification, and detection approach that uses superparamagnetic microbeads in an array of thousands of 100 fL microwells to simplify sample purification and reduce reagent dispensing steps. Primers, attached to superparamagnetic microbeads through a thermo-labile bond, capture and separate target sequences from the sample. The microbeads are then magnetically loaded into a microwell array such that wells predominately contain a single bead. Master mix, lacking primers, is added before sealing the reaction wells with hydrophobic oil. Thermocycling releases the primer pair from the beads during PCR amplification. At low target concentrations, most beads capture, on average, less than one target molecule, and precise, digital PCR quantification can be derived from the percentage of positive reactions. At higher concentrations, qPCR signal is used to determine the average number of target molecules per reaction, significantly extending the dynamic range beyond the digital saturation point. We demonstrate that SIRCA can quantify DNA and RNA targets using thousands of parallel reactions, achieving attomolar limits of detection and a linear dynamic range of 105. The work reported here is a first step towards multiplexed SIRCA assays.


Sujet(s)
Acides nucléiques , ADN/génétique , Séparation immunomagnétique , Champs magnétiques , Réaction de polymérisation en chaine en temps réel
8.
J Clin Endocrinol Metab ; 104(11): 5393-5405, 2019 11 01.
Article de Anglais | MEDLINE | ID: mdl-31393563

RÉSUMÉ

CONTEXT: Previous case reports associated prepubertal gynecomastia with lavender-containing fragrances, but there appear to be no reports of premature thelarche. OBJECTIVE: To add to a case series about lavender-fragranced product use and breast growth in children and to measure endocrine-disrupting chemical activity of essential oil components. DESIGN, SETTING, AND PATIENTS: Patients experiencing premature thelarche or prepubertal gynecomastia with continuous exposure to lavender-fragranced products were evaluated in the pediatric endocrinology departments of two institutions. Mechanistic in vitro experiments using eight components of lavender and other essential oils were performed at National Institute of Environmental Health Sciences. MAIN OUTCOME MEASURES: Case reports and in vitro estrogen and androgen receptor gene expression activities in human cell lines with essential oils. RESULTS: Three prepubertal girls and one boy with clinical evidence of estrogenic action and a history of continuous exposure to lavender-containing fragrances were studied. Breast growth dissipated in all patients with discontinuation of the fragranced products. Some of the components tested elicited estrogenic and antiandrogenic properties of varying degrees. CONCLUSION: We report cases of premature thelarche that resolved upon cessation of lavender-containing fragrance exposure commonly used in Hispanic communities. The precise developmental basis for such conditions could be multifactorial. In vitro demonstration of estrogenic and antiandrogenic properties of essential oil components suggests essential oils in these cases could be considered a possible source and supports a possible link with idiopathic prepubertal breast development. Whether the level of lavender oil estrogenic potency is sufficient to cause these effects is unknown.


Sujet(s)
Région mammaire/physiopathologie , Perturbateurs endocriniens/effets indésirables , Huile essentielle/effets indésirables , Huiles végétales/effets indésirables , Région mammaire/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Enfant , Enfant d'âge préscolaire , Récepteur alpha des oestrogènes/métabolisme , Femelle , Gynécomastie/induit chimiquement , Humains , Lavandula , Mâle , Coactivateur-2 de récepteur nucléaire/métabolisme , Puberté précoce/induit chimiquement , Récepteurs aux androgènes/métabolisme
9.
J Arthroplasty ; 34(11): 2532-2537, 2019 Nov.
Article de Anglais | MEDLINE | ID: mdl-31375287

RÉSUMÉ

BACKGROUND: Health care spending is projected to increase throughout the next decade alongside the number of total joint arthroplasties (TJAs) performed. Such growth places significant financial burden on the economic system. To address these concerns, Bundled Payments for Care Improvement (BPCI) is becoming a favorable reimbursement model. The aim of this study is to present the outcomes with BPCI model focused on the post-acute care (PAC) phase and compare the outcomes between years 1 and 2 of implementation. METHODS: The Joint Utilization Management Program (JUMP) was implemented in January 2014. Inclusion criteria were Medicare patients undergoing primary unilateral in-patient TJA procedures, outpatient procedures that resulted in an in-hospital admission, and trauma episodes that required TJA. Scorecards monitoring surgeons' performance and tracking length of stay (LOS) in the PAC setting were established. The data generated from these scorecards guided percentage sum-allocation from the total gain-shared sum among the participating providers. RESULTS: A total of 683 JUMP patients were assessed over two years. PAC utilization decreased between 2014 and 2015. The average LOS was longer in year 1 than year 2 (4.50 vs 3.19 days). In-patient rehabilitation (IPR) decreased from 6.45% to 3.22%, with a decrease in IPR average LOS of 1.47 days. The rate of 30-day readmission was lower for JUMP patients in 2015 than 2014 (8.77% vs 10.56%), with day of readmission being earlier (11.91 days vs 13.71 days) in 2014. CONCLUSION: Under the BPCI program, our experience with the JUMP model demonstrates higher efficiency of care in the PAC setting through reduced LOS, IPR admission rates, and 30-day readmission rate.


Sujet(s)
Arthroplastie prothétique de hanche , Arthroplastie prothétique de genou , Bouquets de soins des patients , Sujet âgé , Humains , Medicare (USA) , Réadmission du patient , États-Unis
10.
Med Vet Entomol ; 33(1): 31-43, 2019 03.
Article de Anglais | MEDLINE | ID: mdl-30039583

RÉSUMÉ

Nine sandfly species (Diptera: Psychodidae) are suspected or proven vectors of Leishmania spp. in the North and Central America region. The ecological niches for these nine species were modelled in three time periods and the overlaps for all time periods of the geographic predictions (G space), and of ecological dimensions using pairwise comparisons of equivalent niches (E space), were calculated. Two Nearctic, six Neotropical and one species in both bioregions occupied a reduced number of distribution areas. The ecological niche projections for most sandfly species other than Lutzomyia shannoni and Lutzomyia ovallesi have not expanded significantly since the Pleistocene. Only three species increase significantly to 2050, whereas all others remain stable. Lutzomyia longipalpis shared a similar ecological niche with more species than any other, although both L. longipalpis and Lutzomyia olmeca olmeca had conserved distributions over time. Climate change, at both regional and local levels, will play a significant role in the temporal and spatial distributions of sandfly species.


Sujet(s)
Répartition des animaux , Changement climatique , Écosystème , Vecteurs insectes/physiologie , Psychodidae/physiologie , Animaux , Amérique centrale , Leishmania/physiologie , Amérique du Nord
11.
J Intellect Disabil Res ; 62(12): 1008-1017, 2018 12.
Article de Anglais | MEDLINE | ID: mdl-30450801

RÉSUMÉ

BACKGROUND: Self-injurious behaviour (SIB) can be classified as intentional, direct injuring of body tissue usually without suicidal intent. In its non-suicidal form it is commonly seen as a clinical sign of borderline personality disorder, autism, PTSD, depression, and anxiety affecting a wide range of ages and conditions. In rhesus macaques SIB is most commonly manifested through hair plucking, self-biting, self-hitting, and head banging. SIB in the form of self-biting is observed in approximately 5-15% of individually housed monkeys. Recently, glial cells are becoming recognised as key players in regulating behaviours. METHOD: The goal of this study was to determine the role of glial activation, including astrocytes, in macaques that had displayed SIB. To this end, we performed immunohistochemistry and next generation sequence of brain tissues from rhesus macaques with SIB. RESULTS: Our studies showed increased vimentin, but not nestin, expression on astrocytes of macaques displaying SIB. Initial RNA Seq analyses indicate activation of pathways involved in tissue remodelling, neuroinflammation and cAMP signalling. CONCLUSIONS: Glia are most probably activated in primates with self-injury, and are therefore potential novel targets for therapeutics.


Sujet(s)
Encéphale/anatomopathologie , Névroglie/anatomopathologie , Comportement auto-agressif/anatomopathologie , Animaux , Comportement animal , Encéphale/physiopathologie , Modèles animaux de maladie humaine , Immunohistochimie , Macaca mulatta , Comportement auto-agressif/physiopathologie
12.
Anal Chem ; 90(21): 13000-13006, 2018 11 06.
Article de Anglais | MEDLINE | ID: mdl-30335366

RÉSUMÉ

Improvements were made to a previously developed platform coupling microchip capillary electrophoresis (CE) with high pressure mass spectrometry (HPMS). The RF drive frequency was increased to over 30 MHz from less than 10 MHz, and the ion trap was scaled down to 100 µm critical dimensions. A stretched length ion trap was used to improve sensitivity, and a tube lens was used to improve ion transmission. Detection of the 20 common amino acids was demonstrated, resulting in an average improvement of signal-to-noise of 28 times and an average improvement in peak width of 2.6 times over those obtained in previous work. Consumption of amino acids by cells in growth media was monitored over time using the improved CE-HPMS platform, and several amino acids were shown to be consumed at different rates, demonstrating the potential for real-time bioreactor monitoring.


Sujet(s)
Électrophorèse sur puce/instrumentation , Escherichia coli K12/croissance et développement , Laboratoires sur puces , Acides aminés/analyse , Électrophorèse capillaire/méthodes , Électrophorèse sur puce/méthodes , Spectrométrie de masse ESI/méthodes
13.
Science ; 360(6389): 627-632, 2018 05 11.
Article de Anglais | MEDLINE | ID: mdl-29731449

RÉSUMÉ

The precise value of the mean neutron lifetime, τn, plays an important role in nuclear and particle physics and cosmology. It is used to predict the ratio of protons to helium atoms in the primordial universe and to search for physics beyond the Standard Model of particle physics. We eliminated loss mechanisms present in previous trap experiments by levitating polarized ultracold neutrons above the surface of an asymmetric storage trap using a repulsive magnetic field gradient so that the stored neutrons do not interact with material trap walls. As a result of this approach and the use of an in situ neutron detector, the lifetime reported here [877.7 ± 0.7 (stat) +0.4/-0.2 (sys) seconds] does not require corrections larger than the quoted uncertainties.

14.
Proc Natl Acad Sci U S A ; 115(18): E4189-E4198, 2018 05 01.
Article de Anglais | MEDLINE | ID: mdl-29666266

RÉSUMÉ

Early transient developmental exposure to an endocrine active compound, diethylstilbestrol (DES), a synthetic estrogen, causes late-stage effects in the reproductive tract of adult mice. Estrogen receptor alpha (ERα) plays a role in mediating these developmental effects. However, the developmental mechanism is not well known in male tissues. Here, we present genome-wide transcriptome and DNA methylation profiling of the seminal vesicles (SVs) during normal development and after DES exposure. ERα mediates aberrations of the mRNA transcriptome in SVs of adult mice following neonatal DES exposure. This developmental exposure impacts differential diseases between male (SVs) and female (uterus) tissues when mice reach adulthood due to most DES-altered genes that appear to be tissue specific during mouse development. Certain estrogen-responsive gene changes in SVs are cell-type specific. DNA methylation dynamically changes during development in the SVs of wild-type (WT) and ERα-knockout (αERKO) mice, which increases both the loss and gain of differentially methylated regions (DMRs). There are more gains of DMRs in αERKO compared with WT. Interestingly, the methylation changes between the two genotypes are in different genomic loci. Additionally, the expression levels of a subset of DES-altered genes are associated with their DNA methylation status following developmental DES exposure. Taken together, these findings provide an important basis for understanding the molecular and cellular mechanism of endocrine-disrupting chemicals (EDCs), such as DES, during development in the male mouse tissues. This unique evidence contributes to our understanding of developmental actions of EDCs in human health.


Sujet(s)
Méthylation de l'ADN/effets des médicaments et des substances chimiques , Diéthylstilbestrol/effets indésirables , Récepteur alpha des oestrogènes/métabolisme , Oestrogènes nonstéroïdiens/effets indésirables , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Vésicules séminales/métabolisme , Transcriptome/effets des médicaments et des substances chimiques , Animaux , Méthylation de l'ADN/génétique , Diéthylstilbestrol/pharmacologie , Récepteur alpha des oestrogènes/agonistes , Récepteur alpha des oestrogènes/génétique , Oestrogènes nonstéroïdiens/pharmacologie , Locus génétiques , Mâle , Souris , Souris knockout
15.
Environ Health Perspect ; 126(1): 017012, 2018 01 31.
Article de Anglais | MEDLINE | ID: mdl-29389661

RÉSUMÉ

BACKGROUND: Bisphenol A (BPA) is an endocrine-disrupting chemical (EDC) that might be harmful to human health. Recently, there has been widespread usage of bisphenol chemicals (BPs), such as bisphenol AF (BPAF) and bisphenol S (BPS), as replacements for BPA. However, the potential biological actions, toxicity, and the molecular mechanism of these compounds are still poorly understood. OBJECTIVES: Our objective was to examine the estrogenic effects of BPA, BPAF, and BPS and the molecular mechanisms of action in the estrogen receptor alpha (ERα) complex. METHODS: In vitro cell models were used to compare the estrogenic effects of BPA, BPAF, and BPS to estrogen. Microarray Assay for Real-Time Coregulator-Nuclear receptor Interaction (MARCoNI) analysis was used to identify coregulators of BPA, BPAF, and BPS, and molecular dynamic (MD) simulations were used to determine the compounds binding in the ERα complex. RESULTS: We demonstrated that BPA and BPAF have agonistic activity for both ERα and ERß, but BPS has ERα-selective specificity. We concluded that coregulators were differentially recruited in the presence of BPA, BPAF, or BPS. Interestingly, BPS recruited more corepressors when compared to BPA and BPAF. From a series of MD analysis, we concluded that BPA, BPAF, and BPS can bind to the ER-ligand-binding domain with differing energetics and conformations. In addition, the binding surface of coregulator interactions on ERα was characterized for the BPA, BPAF, and BPS complexes. CONCLUSION: These findings further our understanding of the molecular mechanisms of EDCs, such as BPs, in ER-mediated transcriptional activation, biological activity, and their effects on physiological functions in human health. https://doi.org/10.1289/EHP2505.


Sujet(s)
Composés benzhydryliques/toxicité , Perturbateurs endocriniens/toxicité , Phénols/toxicité , Sulfones/toxicité , Lignée cellulaire tumorale , Perturbateurs endocriniens/métabolisme , Récepteur alpha des oestrogènes/effets des médicaments et des substances chimiques , Récepteur alpha des oestrogènes/métabolisme , Récepteur bêta des oestrogènes/effets des médicaments et des substances chimiques , Récepteur bêta des oestrogènes/métabolisme , Oestrogènes/pharmacologie , Humains , Ligands , Analyse sur microréseau , Simulation de dynamique moléculaire
16.
Med Vet Entomol ; 32(1): 102-110, 2018 03.
Article de Anglais | MEDLINE | ID: mdl-28892179

RÉSUMÉ

The behavioural and electrophysiological (electroantennography) responses of the first two instars of Triatoma dimidiata (Hemiptera: Reduviidae) Latreille to fresh and dry faecal headspace volatile extracts from fifth instar conspecific nymphs and synthetic compounds were analysed in this study. Recently emerged nymphs (3-5 days) aggregated around filter paper impregnated with dry faeces and around filter paper impregnated with extracts from both fresh and dry faeces. Older first instars (10-15 days) and second instars aggregated around filter paper impregnated with fresh and dry faeces, and their respective headspace extracts. Dry faecal volatile extracts elicited the strongest antennal responses, followed by fresh faecal extracts. Gas chromatography-mass spectrometry analysis of dried faecal headspace volatiles demonstrated the presence of 12 compounds: 2-ethyl-1-hexanol, 1,2,4-trimethylbenzene, n-octadecane, n-nonadecane, n-eicosane, n-heneicosane, n-tricosane, n-pentaeicosane, n-hexaeicosane, n-octaeicosane, nonanal, and 4-methyl quinazoline. In fresh faecal headspace extracts, only nonanal was clearly detected, although there were other trace compounds, including several unidentified sesquiterpenes. Four of the 11 compounds tested individually elicited aggregation behaviour at concentrations of 100 ng/µL and 1 µg/µL. A blend containing these four components also mediated the aggregation of nymphs. These volatiles may be valuable for developing monitoring methods and designing sensitive strategies to detect and measure T. dimidiata infestation.


Sujet(s)
Antennes des arthropodes/physiologie , Chimiotaxie , Fèces/composition chimique , Triatoma/physiologie , Composés organiques volatils/analyse , Animaux , Phénomènes électrophysiologiques , Nymphe/croissance et développement , Nymphe/physiologie , Comportement social , Triatoma/croissance et développement
17.
J Anim Physiol Anim Nutr (Berl) ; 102(2): e787-e797, 2018 Apr.
Article de Anglais | MEDLINE | ID: mdl-29130533

RÉSUMÉ

The objective of this study was to examine the relationship between mitochondrial proton leak and feed efficiency with supplementation of different levels of Cu, Mn and Zn (Bioplex, Alltech) at levels above Nutrient Requirements of Dairy Cattle (NRC, 2001). Milk yield and composition, mineral excretion in milk and faeces, feed efficiency and liver mitochondrial proton leak were measured in 60 Holstein dairy cows at approximately 70 days in milk on a commercial dairy. Treatments reflect total Cu, Mn and Zn intake/day and are as follows: (i) High: 444 mg/day Cu, 3492 mg/day Mn, 2234 mg/day Zn; (ii) Med: 436 mg/day Cu, 3002 mg/day Mn, 2047 mg/day Zn; (iii) Low: 420 mg/day Cu, 2764 mg/day Mn, 2186 mg/day Zn; (iv) LowMn: 391 mg/day Cu, 2617 mg/day Mn, 1849 mg/day Zn; and (v) Control: 264 mg/day Cu, 2850 mg/day Mn, 1593 mg/day Zn. Proton leak-dependent respiration was lowest in Control (p < .10). However, measures of efficiency were greatest in Med and least in High (p < .10). Therefore, measures of efficiency did not reflect efficiency due to low proton leak and there appears to be an upper limit to beneficial supplementation of Cu, Mn and Zn.


Sujet(s)
Bovins , Cuivre/administration et posologie , Lactation/effets des médicaments et des substances chimiques , Manganèse/administration et posologie , Mitochondries du foie/métabolisme , Zinc/administration et posologie , Aliment pour animaux/analyse , Phénomènes physiologiques nutritionnels chez l'animal , Animaux , Régime alimentaire/médecine vétérinaire , Compléments alimentaires , Femelle , Lactation/métabolisme , Lait , Consommation d'oxygène/effets des médicaments et des substances chimiques , Consommation d'oxygène/physiologie
18.
Med Vet Entomol ; 32(1): 84-101, 2018 03.
Article de Anglais | MEDLINE | ID: mdl-28887895

RÉSUMÉ

Climate change can influence the geographical range of the ecological niche of pathogens by altering biotic interactions with vectors and reservoirs. The distributions of 20 epidemiologically important triatomine species in North America were modelled, comparing the genetic algorithm for rule-set prediction (GARP) and maximum entropy (MaxEnt), with or without topographical variables. Potential shifts in transmission niche for Trypanosoma cruzi (Trypanosomatida: Trypanosomatidae) (Chagas, 1909) were analysed for 2050 and 2070 in Representative Concentration Pathway (RCP) 4.5 and RCP 8.5. There were no significant quantitative range differences between the GARP and MaxEnt models, but GARP models best represented known distributions for most species [partial-receiver operating characteristic (ROC) > 1]; elevation was an important variable contributing to the ecological niche model (ENM). There was little difference between niche breadth projections for RCP 4.5 and RCP 8.5; the majority of species shifted significantly in both periods. Those species with the greatest current distribution range are expected to have the greatest shifts. Positional changes in the centroid, although reduced for most species, were associated with latitude. A significant increase or decrease in mean niche elevation is expected principally for Neotropical 1 species. The impact of climate change will be specific to each species, its biogeographical region and its latitude. North American triatomines with the greatest current distribution ranges (Nearctic 2 and Nearctic/Neotropical) will have the greatest future distribution shifts. Significant shifts (increases or decreases) in mean elevation over time are projected principally for the Neotropical species with the broadest current distributions. Changes in the vector exposure threat to the human population were significant for both future periods, with a 1.48% increase for urban populations and a 1.76% increase for rural populations in 2050.


Sujet(s)
Répartition des animaux , Maladie de Chagas/transmission , Changement climatique , Vecteurs insectes/physiologie , Reduviidae/physiologie , Trypanosoma cruzi/physiologie , Animaux , Maladie de Chagas/parasitologie , Vecteurs insectes/parasitologie , Mexique , Modèles biologiques , Reduviidae/parasitologie , États-Unis
19.
Cell Biochem Funct ; 35(8): 527-537, 2017 Dec.
Article de Anglais | MEDLINE | ID: mdl-29243276

RÉSUMÉ

The purpose of this study was to determine if Shc proteins influence the metabolic response to acute (7 days) feeding of a high-fat diet (HFD). To this end, whole animal energy expenditure (EE) and substrate oxidation were measured in the Shc knockout (ShcKO) and wild-type (WT) mice fed a control or HFD. The activities of enzymes of glycolysis, the citric acid cycle, electron transport chain (ETC), and ß-oxidation were also investigated in liver and skeletal muscle of ShcKO and WT animals. The study showed that ShcKO increases (P < .05) EE adjusted for either total body weight or lean mass. This change in EE could contribute to decreases in weight gain in ShcKO versus WT mice fed an HFD. Thus, our results indicate that Shc proteins should be considered as potential targets for developing interventions to mitigate weight gain on HFD by stimulating EE. Although decreased levels of Shc proteins influenced the activity of some enzymes in response to high-fat feeding (eg, increasing the activity of acyl-CoA dehydrogenase), it did not produce concerted changes in enzymes of glycolysis, citric acid cycle, or the ETC. The physiological significance of observed changes in select enzyme activities remains to be determined. SIGNIFICANCE OF THE STUDY: We report higher EE in ShcKO versus WT mice when consuming the HFD. Although decreased levels of Shc proteins influenced the activity of a central enzyme of ß-oxidation in response to high-fat feeding, it did not produce concerted changes in enzymes of glycolysis, citric acid cycle, or the ETC. Thus, an increase in EE in response to consumption of an HFD may be a mechanism that leads to decreased weight gain previously reported in ShcKO mice with long-term consumption of an HFD.


Sujet(s)
Alimentation riche en graisse/effets indésirables , Métabolisme énergétique , Protéines adaptatrices de signalisation Shc/métabolisme , Animaux , Mâle , Souris , Souris de lignée C57BL , Souris knockout , Protéines adaptatrices de signalisation Shc/déficit , Prise de poids
20.
Chem Commun (Camb) ; 54(2): 204-207, 2017 Dec 21.
Article de Anglais | MEDLINE | ID: mdl-29230440

RÉSUMÉ

Herein we describe a synthetically simple strategy for increasing the lifetime of unstructured peptides in cytosolic environment via dimerization at the N-terminus to block threading into the catalytic cleft of cytosolic proteases. We establish this approach with kinase substrates, allowing for phosphorylation in cells as a demonstration of protease resistance.


Sujet(s)
Cytosol/enzymologie , Peptide hydrolases/métabolisme , Peptides/pharmacologie , Inhibiteurs de protéases/pharmacologie , Lignée cellulaire , Dimérisation , Cellules HeLa , Humains , Structure moléculaire , Peptides/synthèse chimique , Peptides/composition chimique , Inhibiteurs de protéases/composition chimique
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