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1.
Phys Rev Lett ; 128(13): 132501, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35426696

RESUMO

We report the first measurement of the parity-violating elastic electron scattering asymmetry on ^{27}Al. The ^{27}Al elastic asymmetry is A_{PV}=2.16±0.11(stat)±0.16(syst) ppm, and was measured at ⟨Q^{2}⟩=0.02357±0.00010 GeV^{2}, ⟨θ_{lab}⟩=7.61°±0.02°, and ⟨E_{lab}⟩=1.157 GeV with the Q_{weak} apparatus at Jefferson Lab. Predictions using a simple Born approximation as well as more sophisticated distorted-wave calculations are in good agreement with this result. From this asymmetry the ^{27}Al neutron radius R_{n}=2.89±0.12 fm was determined using a many-models correlation technique. The corresponding neutron skin thickness R_{n}-R_{p}=-0.04±0.12 fm is small, as expected for a light nucleus with a neutron excess of only 1. This result thus serves as a successful benchmark for electroweak determinations of neutron radii on heavier nuclei. A tree-level approach was used to extract the ^{27}Al weak radius R_{w}=3.00±0.15 fm, and the weak skin thickness R_{wk}-R_{ch}=-0.04±0.15 fm. The weak form factor at this Q^{2} is F_{wk}=0.39±0.04.

2.
J Hum Nutr Diet ; 33(6): 876-880, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32975829

RESUMO

BACKGROUND: Portable gluten sensors are now commercially available to the public, although there is genuine uncertainty within the medical community over whether they should be used for coeliac disease management. The present study described qualitatively the experience of using a portable gluten sensor for 15 adults and 15 adolescents with coeliac disease participating in a 3-month pilot clinical trial. METHODS: Participants were 30 individuals, aged 13-70 years, with biopsy-confirmed coeliac disease on a gluten-free diet. All received a portable gluten sensor and were randomised to low, medium, and high numbers of single-use capsules. Open-ended questions addressed likes and dislikes using the portable gluten sensor after 3 months. Major themes were identified and described. RESULTS: Participants liked that the portable gluten sensor provided extra assurance to check foods presented as gluten-free, the convenient size and portability, the added sense of control, and overall peace-of-mind. Participants disliked having attention drawn to them when using the sensor and feeling as if they were deterring others from eating. Participants also disliked the physical difficulty associated with using the capsules, questionable accuracy and the inability to test fermented foods. Adults were more enthusiastic about the sensor than adolescents. CONCLUSIONS: Positive and negative experiences may be expected when using commercially available portable gluten sensors to help manage coeliac disease. As future versions of this and other gluten sensors become available, it will be important to investigate the relationship between users' experience with the sensors and long-term outcomes such as mucosal healing and quality of life.


Assuntos
Doença Celíaca/psicologia , Dieta Livre de Glúten/instrumentação , Dieta Livre de Glúten/psicologia , Análise de Alimentos/instrumentação , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Adolescente , Adulto , Idoso , Doença Celíaca/dietoterapia , Emoções , Comportamento Alimentar/psicologia , Feminino , Glutens/análise , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Pesquisa Qualitativa , Qualidade de Vida , Adulto Jovem
3.
Phys Rev Lett ; 125(11): 112502, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32976004

RESUMO

A beam-normal single-spin asymmetry generated in the scattering of transversely polarized electrons from unpolarized nucleons is an observable related to the imaginary part of the two-photon exchange process. We report a 2% precision measurement of the beam-normal single-spin asymmetry in elastic electron-proton scattering with a mean scattering angle of θ_{lab}=7.9° and a mean energy of 1.149 GeV. The asymmetry result is B_{n}=-5.194±0.067(stat)±0.082 (syst) ppm. This is the most precise measurement of this quantity available to date and therefore provides a stringent test of two-photon exchange models at far-forward scattering angles (θ_{lab}→0) where they should be most reliable.

4.
J Comp Pathol ; 175: 64-68, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32138844

RESUMO

A 15-year-old neutered male miniature pinscher was presented with a pedunculated mass (4 × 1 cm) in its urinary bladder. Exploratory cystotomy revealed that the mass was located at the trigone of the bladder and projected into the lumen. The cut surface of the mass was homogeneous grey to tan in colour with focal brown pigmentation. Microscopically, the mass was predominantly composed of neoplastic spindle cells characterized by moderate cellular pleomorphism, invasion into the muscular layer of the bladder wall and few mitotic figures. The neoplastic spindle cells formed interwoven bundles intersecting at various angles. Immunohistochemically, these cells were negative for cytokeratin 7 and α-smooth muscle actin, but strongly expressed S100 and vimentin, confirming a diagnosis of a malignant peripheral nerve sheath tumour (PNST). To the best of our knowledge, this is the first report of a primary malignant PNST in the urinary bladder of a dog.


Assuntos
Doenças do Cão/patologia , Neoplasias de Bainha Neural/veterinária , Neoplasias da Bexiga Urinária/veterinária , Animais , Cães , Masculino
5.
Osteoporos Int ; 31(1): 59-66, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31377915

RESUMO

Skeletal fragility is a common complication of childhood acute lymphoblastic leukaemia (ALL) but the impact of bisphosphonate therapy on bone mass and fracture is unclear. We aim to conduct a systematic review to evaluate the effects of bisphosphonates on bone mineral density (BMD) and fracture incidence in children with ALL. METHODS: EMBASE, Medline and the Cochrane Library were thoroughly searched by two researchers. Inclusion criteria was any child under the age of 18 years with a diagnosis of ALL, who had received any bisphosphonate treatment and had serial measurements of bone density performed thereafter. All primary research studies of any study design, excluding case reports, were included. RESULTS: Ten full text papers were identified with two exclusively meeting the inclusion criteria. Both studies administered bisphosphonates to children receiving maintenance chemotherapy for varying durations. Bone density was assessed at regular intervals by dual x-ray absorptiometry (DXA). The majority of participants had an improvement in bone density at the end of each study. However, no size adjustment of DXA data was performed. Limited information on fracture occurrence was provided by one study but did not include routine screening for vertebral fractures. CONCLUSIONS: This systematic review identified that there is insufficient evidence to support routine use of prophylactic bisphosphonate therapy in childhood ALL for prevention of fracture and improvement of bone mass. Future well-designed clinical trials in those at highest risk of fractures in ALL are now needed.


Assuntos
Densidade Óssea , Difosfonatos , Fraturas Ósseas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adolescente , Criança , Difosfonatos/uso terapêutico , Feminino , Fraturas Ósseas/etiologia , Fraturas Ósseas/prevenção & controle , Humanos , Incidência , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Estudos Prospectivos , Estudos Retrospectivos
6.
Epidemiol Infect ; 147: e203, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-31364537

RESUMO

Norovirus, a major cause of gastroenteritis in people of all ages worldwide, was first reported in South Korea in 1999. The most common causal agents of pediatric acute gastroenteritis are norovirus and rotavirus. While vaccination has reduced the pediatric rotavirus infection rate, norovirus vaccines have not been developed. Therefore, prediction and prevention of norovirus are very important. Norovirus is divided into genogroups GI-GVII, with GII.4 being the most prevalent. However, in 2012-2013, GII.17 showed a higher incidence than GII.4 and a novel variant, GII.P17-GII.17, appeared. In this study, 204 stool samples collected in 2013-2014 were screened by reverse transcriptase-polymerase chain reaction; 11 GI (5.39%) and 45 GII (22.06%) noroviruses were identified. GI.4, GI.5, GII.4, GII.6 and GII.17 were detected. The whole genomes of the three norovirus GII.17 were sequenced. The whole genome of GII.17 consists of three open reading frames of 5109, 1623 and 780 bp. Compared with 20 GII.17 strains isolated in other countries, we observed numerous changes in the protruding P2 domain of VP1 in the Korean GII.17 viruses. Our study provided genome information that might aid in epidemic prevention, epidemiology studies and vaccine development.


Assuntos
Infecções por Caliciviridae/virologia , Gastroenterite/virologia , Genótipo , Norovirus/genética , Norovirus/isolamento & purificação , Análise de Sequência , Sequenciamento Completo do Genoma , Infecções por Caliciviridae/epidemiologia , Fezes/virologia , Gastroenterite/epidemiologia , Humanos , Incidência , Epidemiologia Molecular , Norovirus/classificação , Fases de Leitura Aberta , Filogenia , República da Coreia/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência
7.
J Hum Nutr Diet ; 32(3): 311-320, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30834587

RESUMO

BACKGROUND: Certain approaches to managing a strict gluten-free diet (GFD) for coeliac disease (CD) may lead to impaired psychosocial well-being, a diminished quality of life (QOL) and disordered eating. The present study aimed to understand adolescents' approaches to managing a GFD and the association with QOL. METHODS: Thirty adolescents with CD (13-17 years old) following the GFD for at least 1 year completed the Celiac Dietary Adherence Test (CDAT) and QOL survey. Their approaches to GFD management were explored using a semi-structured interview, where key themes were developed using an iterative process, and further analysed using a psychosocial rubric to classify management strategies and QOL. CDAT ratings were compared across groups. RESULTS: Gluten-free diet management strategies were classified on a four-point scale. Adaptive eating behaviours were characterised by greater flexibility (versus rigidity), trust (versus avoidance), confidence (versus controlling behaviour) and awareness (versus preoccupation) with respect to maintaining a GFD. Approximately half the sample (53.3%) expressed more maladaptive approaches to maintaining a GFD and those who did so were older with lower CD-Specific Pediatric Quality of Life (CDPQOL) scores, mean subscale differences ranging from 15.0 points for Isolation (t = 2.4, P = 0.03, d.f. = 28) to 23.4 points for Limitations (t = 3.0, P = 0.01, d.f. = 28). CONCLUSIONS: Adolescents with CD who manage a GFD with maladaptive eating behaviours similar to known risk factors for feeding and eating disorders experience diminished QOL. In accordance with CD management recommendations, we recommend ongoing follow-up with gastroenterologists and dietitians and psychosocial support referrals, as needed.


Assuntos
Doença Celíaca/psicologia , Dieta Livre de Glúten/psicologia , Comportamento Alimentar/psicologia , Cooperação do Paciente/psicologia , Qualidade de Vida , Adaptação Psicológica , Adolescente , Doença Celíaca/dietoterapia , Estudos Transversais , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Feminino , Humanos , Masculino , Pesquisa Qualitativa , Fatores de Risco , Inquéritos e Questionários
8.
Epidemiol Infect ; 146(7): 839-847, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29534770

RESUMO

Human bocaviruses (HBoVs) have been detected in human gastrointestinal infections worldwide. In 2005, HBoV was also discovered in infants and children with infections of the lower respiratory tract. Recently, several genotypes of this parvovirus, including HBoV genotype 2 (HBoV2), genotype 3 (HBoV3) and genotype 4 (HBoV4), were discovered and found to be closely related to HBoV. HBoV2 was first detected in stool samples from children in Pakistan, followed by detection in other countries. HBoV3 was detected in Australia and HBoV4 was identified in stool samples from Nigeria, Tunisia and the USA. Recently, HBoV infection has been on the rise throughout the world, particularly in countries neighbouring South Korea; however, there have been very few studies on Korean strains. In this study, we characterised the whole genome and determined the phylogenetic position of CUK-BC20, a new clinical HBoV strain isolated in South Korea. The CUK-BC20 genome of 5184 nucleotides (nt) contains three open-reading frames (ORFs). The genotype of CUK-BC20 is HBoV2, and 98.77% of its nt sequence is identical with those of other HBoVs, namely Rus-Nsc10-N386. Especially, the ORF3 amino acid sequences from positions 212-213 and 454 corresponding to a variable region (VR)1 and VR5, respectively, showed genotype-specific substitutions that distinguished the four HBoV genotypes. As the first whole-genome sequence analysis of HBoV in South Korea, this information will provide a valuable reference for the detection of recombination, tracking of epidemics and development of diagnosis methods for HBoV.


Assuntos
Genoma Viral , Bocavirus Humano/genética , Infecções por Parvoviridae/virologia , Sequência de Aminoácidos , Bocavirus Humano/classificação , Humanos , Lactente , Masculino , Infecções por Parvoviridae/classificação , Filogenia , República da Coreia , Alinhamento de Sequência/veterinária , Sequenciamento Completo do Genoma
9.
Br J Oral Maxillofac Surg ; 55(8): 822-829, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28864147

RESUMO

The aim of this randomised controlled clinical trial was to assess the early efficacy of bone morphogenetic protein-2 with hydroxyapatite granules (BMP-2/hydroxyapatite) on augmentation of the alveolar ridge, by comparing changes in volume with those associated with the use of an inorganic bovine-derived xenograft (BDX). We studied 20 patients who were divided into two groups using a table of random numbers, and BMP-2/hydroxyapatite and BDX were applied accordingly. Computed tomographic (CT) images and panoramic radiographs were obtained immediately after operation and four months later. CT images were reconstructed in three dimensions to measure volumetric changes, and linear measurements were made on panoramic images. The mean (SD) absorption rates for BMP-2/hydroxyapatite and BDX were 13.2 (8.8)% and 13.8 (20.5)%, respectively. While the mean value did not differ significantly between the two materials, the SD was higher in the BDX group than in the BMP-2/hydroxyapatite group. No clinically important complications occurred in either group. We conclude that both BMP-2/hydroxyapatite and BDX were effective in augmenting the alveolar ridge, but BMP-2/hydroxyapatite seemed to be more useful in complicated bone defects.


Assuntos
Perda do Osso Alveolar/cirurgia , Aumento do Rebordo Alveolar/métodos , Materiais Biocompatíveis , Proteína Morfogenética Óssea 2/administração & dosagem , Transplante Ósseo , Durapatita , Fator de Crescimento Transformador beta/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Processo Alveolar/anatomia & histologia , Animais , Bovinos , Feminino , Xenoenxertos , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Proteínas Recombinantes/administração & dosagem , Método Simples-Cego , Adulto Jovem
10.
J Hum Nutr Diet ; 29(3): 383-90, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26194359

RESUMO

BACKGROUND: There is little information available on the use of social support systems for patients with coeliac disease (CD). We performed a cross-sectional study aiming to examine the association between participation in different types of social support networks and quality of life (QOL) in adults with CD. METHODS: A survey including a validated CD specific QOL instrument was administered online and in-person to adults with CD who were following a gluten-free diet. Participation in social support networks (type, frequency and duration) were assessed. RESULTS: Among the 2138 participants, overall QOL scores were high, averaging 68.9 out of 100. Significant differences in QOL scores were found for age, length of time since diagnosis and level of education. Most (58%) reported using no social support networks. Of the 42% reporting use of social support networks (online 17.9%, face-to-face 10.8% or both 12.8%), QOL scores were higher for those individuals who used only face-to-face social support compared to only online support (72.6 versus 66.7; P < 0.0001). A longer duration of face-to-face social support use was associated with higher QOL scores (P < 0.0005). By contrast, a longer duration and increased frequency of online social support use was associated with lower QOL scores (P < 0.03). CONCLUSIONS: Participation in face-to-face social support networks is associated with greater QOL scores compared to online social support networks. These findings have potential implications for the management of individuals with CD. Emphasis on face-to-face support may improve long-term QOL and patient outcomes.


Assuntos
Doença Celíaca/psicologia , Redes Comunitárias , Qualidade de Vida , Apoio Social , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
11.
J Dairy Sci ; 97(9): 5587-91, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25022682

RESUMO

Nonantibiotic treatments for mastitis are needed in organic dairy herds. Plant-derived oils may be useful but efficacy and potential mechanisms of action of such oils in mastitis therapy have not been well documented. The objective of the current study was to evaluate the antibacterial activity of the plant-derived oil components of Phyto-Mast (Bovinity Health LLC, Narvon, PA), an herbal intramammary product, against 3 mastitis-causing pathogens: Staphylococcus aureus, Staphylococcus chromogenes, and Streptococcus uberis. Plant-derived oils evaluated were Thymus vulgaris (thyme), Gaultheria procumbens (wintergreen), Glycyrrhiza uralensis (Chinese licorice), Angelica sinensis, and Angelica dahurica. Broth dilution testing according to standard protocol was performed using ultrapasteurized whole milk instead of broth. Controls included milk only (negative control), milk + bacteria (positive control), and milk + bacteria + penicillin-streptomycin (antibiotic control, at 1 and 5% concentrations). Essential oil of thyme was tested by itself and not in combination with other oils because of its known antibacterial activity. The other plant-derived oils were tested alone and in combination for a total of 15 treatments, each replicated 3 times and tested at 0.5, 1, 2, and 4% to simulate concentrations potentially achievable in the milk within the pre-dry-off udder quarter. Thyme oil at concentrations ≥2% completely inhibited bacterial growth in all replications. Other plant-derived oils tested alone or in various combinations were not consistently antibacterial and did not show typical dose-response effects. Only thyme essential oil had consistent antibacterial activity against the 3 mastitis-causing organisms tested in vitro. Further evaluation of physiological effects of thyme oil in various preparations on mammary tissue is recommended to determine potential suitability for mastitis therapy.


Assuntos
Antibacterianos/farmacologia , Óleos de Plantas/farmacologia , Animais , Bovinos , Feminino , Glândulas Mamárias Animais/efeitos dos fármacos , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/tratamento farmacológico , Mastite Bovina/microbiologia , Leite/microbiologia , Óleos Voláteis/farmacologia , Staphylococcus/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Streptococcus/efeitos dos fármacos , Thymus (Planta)/química
12.
Acta Anaesthesiol Scand ; 58(5): 580-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24645718

RESUMO

BACKGROUND: Catheterisation of the internal jugular vein (IJV) can be difficult in infants. We aimed to evaluate whether a simple manoeuvre, a slight caudo-lateral traction of the ipsilateral arm (CLTIA), could decrease the head rotation-induced overlap of the IJV to the carotid artery (CA) in infants. METHODS: Twenty-five infants were included. The patients were placed in the 10° Trendelenburg position with a shoulder roll. On both sides of the neck, ultrasound images were obtained in a transverse orientation before and after the CLTIA at 0°, 40°, and 80° of head rotation, respectively. On each image, CA overlap was calculated as follows: CA overlap (%) = (overlap distance/CA diameter) × 100. RESULTS: The CLTIA decreased CA overlap (%) in 0°, 40°, and 80° of head rotation on the right side of the neck [14 (interquartile range, IQR 0-32) to 0 (IQR 0-14), 24 (IQR 0-46) to 0 (IQR 0-33), and 31 (IQR 12-58) to 23 (IQR 0-34); all P < 0.01] and on the left [29 (IQR 7-61) to 19 (IQR 0-44), 40 (IQR 21-65) to 31 (IQR 0-46), and 44 (IQR 29-97) to 33 (IQR 14-69); all P < 0.01], respectively. CONCLUSION: The CLTIA successfully reduced the overlap between the IJV and the CA in infants. However, further study should be needed to evaluate the clinical usefulness of the CLTIA during the IJV catheterisation.


Assuntos
Artérias Carótidas , Cateterismo Venoso Central/métodos , Veias Jugulares , Posicionamento do Paciente/métodos , Anestesia Geral , Artérias Carótidas/anatomia & histologia , Procedimentos Cirúrgicos Eletivos , Feminino , Cabeça , Decúbito Inclinado com Rebaixamento da Cabeça , Humanos , Lactente , Veias Jugulares/anatomia & histologia , Masculino , Estudos Prospectivos , Rotação , Método Simples-Cego
13.
Phys Rev Lett ; 111(14): 141803, 2013 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-24152148

RESUMO

The Q(weak) experiment has measured the parity-violating asymmetry in ep elastic scattering at Q(2)=0.025(GeV/c)(2), employing 145 µA of 89% longitudinally polarized electrons on a 34.4 cm long liquid hydrogen target at Jefferson Lab. The results of the experiment's commissioning run, constituting approximately 4% of the data collected in the experiment, are reported here. From these initial results, the measured asymmetry is A(ep)=-279±35 (stat) ± 31 (syst) ppb, which is the smallest and most precise asymmetry ever measured in ep scattering. The small Q(2) of this experiment has made possible the first determination of the weak charge of the proton Q(W)(p) by incorporating earlier parity-violating electron scattering (PVES) data at higher Q(2) to constrain hadronic corrections. The value of Q(W)(p) obtained in this way is Q(W)(p)(PVES)=0.064±0.012, which is in good agreement with the standard model prediction of Q(W)(p)(SM)=0.0710±0.0007. When this result is further combined with the Cs atomic parity violation (APV) measurement, significant constraints on the weak charges of the up and down quarks can also be extracted. That PVES+APV analysis reveals the neutron's weak charge to be Q(W)(n)(PVES+APV)=-0.975±0.010.

14.
Anaesthesia ; 68(9): 931-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23841798

RESUMO

We evaluated the effects of three airway manipulation manoeuvres: (a) conventional (single-handed chin lift); (b) backward, upward and right-sided pressure (BURP) manoeuvre; and (c) modified jaw thrust manoeuvre (two-handed aided by an assistant) on laryngeal view and intubation time using the Clarus Video System in 215 patients undergoing general anaesthesia with orotracheal intubation. In the first part of this study, the laryngeal view was recorded as a modified Cormack-Lehane grade with each manoeuvre. In the second part, intubation was performed using the assigned airway manipulation. The primary outcome was the time to intubation, and the secondary outcomes were the modified Cormack-Lehane grade, the number of attempts and the overall success rate. There were significant differences in modified Cormack-Lehane grade between the three airway manipulations (p < 0.0001). Post-hoc analysis indicated that the modified jaw thrust improved the laryngeal view compared with the conventional (p < 0.0001) and the BURP manoeuvres (p < 0.0001). The BURP worsened the laryngeal view compared with the conventional manoeuvre (p = 0.0132). The time to intubation in the modified jaw thrust group was shorter than with the conventional manoeuvre (p = 0.0004) and the BURP group (p < 0.0001). We conclude that the modified jaw thrust is the most effective manoeuvre at improving the laryngeal view and shortening intubation time with the Clarus Video System.


Assuntos
Intubação Intratraqueal/instrumentação , Intubação Intratraqueal/métodos , Gravação em Vídeo/instrumentação , Análise de Variância , Desenho de Equipamento/métodos , Feminino , Tecnologia de Fibra Óptica , Humanos , Arcada Osseodentária , Laringoscópios , Laringoscopia/instrumentação , Laringoscopia/métodos , Masculino , Pessoa de Meia-Idade , Postura , Pressão , Tempo
15.
Biochemistry ; 52(35): 6127-36, 2013 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-23879692

RESUMO

Many cellular processes involve interactions between membrane-associated proteins, and those interactions are enhanced by membrane association. We have used cross-linking reactions to compare the extent and specificity of protein interactions in solution versus on a membrane surface. Cysteine mutants of a soluble cytoplasmic fragment (CF) of the aspartate receptor, a transmembrane receptor involved in bacterial chemotaxis, are used in disulfide bond formation with the thiol-specific oxidant diamide and chemical cross-linking reactions with the trifunctional maleimide TMEA. CF binding to membranes is mediated by its N-terminal His tag binding to vesicles containing a nickel-chelating lipid, so cross-linking reactions conducted in the presence and absence of vesicles differ only in whether CF is bound to the vesicles or is free in solution. For multiple Cys throughout the CF, membrane association is shown to increase the rate and extent of these reactions. Cross-linking specificity, which is measured as the preference for cross-linking between Cys near each other in the native structure, is also enhanced by membrane association. These results provide an experimental demonstration that membrane binding enhances protein-protein interactions, an important consideration for understanding processes involving membrane-associated proteins. The experiments further demonstrate the importance of cross-linking conditions for these reactions that are often used to probe protein structure and dynamics and the potential of membrane association to restore native interactions of membrane-associated proteins for cross-linking studies.


Assuntos
Reagentes de Ligações Cruzadas/química , Maleimidas/química , Proteínas de Membrana/química , Cristalografia por Raios X , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Modelos Moleculares , Mutagênese
16.
Phys Rev Lett ; 110(11): 113602, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25166531

RESUMO

We study the effects of relativistic motion on quantum teleportation and propose a realizable experiment where our results can be tested. We compute bounds on the optimal fidelity of teleportation when one of the observers undergoes nonuniform motion for a finite time. The upper bound to the optimal fidelity is degraded due to the observer's motion. However, we discuss how this degradation can be corrected. These effects are observable for experimental parameters that are within reach of cutting-edge superconducting technology.

17.
Anaesthesia ; 67(7): 755-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22506571

RESUMO

This study assessed the relationship between the occurrence of apnoea-hypopnoea during propofol sedation for spinal anaesthesia and two different predictive tests of sleep apnoea: the STOP-Bang score (snoring while sleeping, daytime tiredness, observed breathing stoppages, high blood pressure-body mass index, age, neck circumference, gender); and the obstructive sleep apnoea (OSA) score. Thirty-four middle-aged men not diagnosed with obstructive sleep apnoea received propofol infusions adjusted to produce a bispectral index of 70-75. ApnoeaLink(TM) was used to estimate the incidence of apnoea-hypopnoea. The median (IQR [range]) apnoea-hypopnoea index was 17 (8-24 [0-70]) events.h(-1) and correlated weakly with the STOP-Bang score (p = 0.022, r = 0.423) and moderately with the OSA score (p < 0.001, r = 0.693). Severe apnoea-hypopnoea developed more frequently in patients with a higher OSA score (34.5% vs 0%) or higher STOP-Bang score (27.6% vs 6.9%). Both assessment tools have some predictive value for the occurrence of apnoea-hypopnoea during propofol sedation in patients undergoing spinal anaesthesia.


Assuntos
Raquianestesia/efeitos adversos , Sedação Consciente/efeitos adversos , Hipnóticos e Sedativos/efeitos adversos , Propofol/efeitos adversos , Apneia Obstrutiva do Sono/induzido quimicamente , Adulto , Idoso , Raquianestesia/métodos , Sedação Consciente/métodos , Humanos , Complicações Intraoperatórias/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Exame Físico/métodos , Valor Preditivo dos Testes , Próstata/cirurgia , Fatores de Risco , Índice de Gravidade de Doença , Apneia Obstrutiva do Sono/diagnóstico , Bexiga Urinária/cirurgia
18.
Pharmacol Ther ; 135(1): 54-70, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22484805

RESUMO

Estrogen is a potent steroid with pleiotropic effects, which have yet to be fully elucidated. Estrogen has both nuclear and non-nuclear effects. The rapid response to estrogen, which involves a membrane associated estrogen receptor(ER) and is protective, involves signaling through PI3K, Akt, and ERK 1/2. The nuclear response is much slower, as the ER-estrogen complex moves to the nucleus, where it functions as a transcription factor, both activating and repressing gene expression. Several different ERs regulate the specificity of response to estrogen, and appear to have specific effects in cardiac remodeling and the response to injury. However, much remains to be understood about the selectivity of these receptors and their specific effects on gene expression. Basic studies have demonstrated that estrogen treatment prevents apoptosis and necrosis of cardiac and endothelial cells. Estrogen also attenuates pathologic cardiac hypertrophy. Estrogen may have great benefit in aging as an anti-inflammatory agent. However, clinical investigations of estrogen have had mixed results, and not shown the clear-cut benefit of more basic investigations. This can be explained in part by differences in study design: in basic studies estrogen treatment was used immediately or shortly after ovariectomy, while in some key clinical trials, estrogen was given years after menopause. Further basic research into the underlying molecular mechanisms of estrogen's actions is essential to provide a better comprehension of the many properties of this powerful hormone.


Assuntos
Doenças Cardiovasculares/metabolismo , Sistema Cardiovascular/metabolismo , Estrogênios/metabolismo , Envelhecimento/metabolismo , Animais , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/fisiopatologia , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/fisiopatologia , Doenças Cardiovasculares/prevenção & controle , Sistema Cardiovascular/fisiopatologia , Terapia de Reposição de Estrogênios , Estrogênios/uso terapêutico , Humanos , Inflamação/metabolismo , Menopausa/metabolismo , Miocárdio/metabolismo , Receptores de Estrogênio/metabolismo , Transdução de Sinais
19.
Transplant Proc ; 44(2): 512-5, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22410058

RESUMO

PURPOSE: The aim of this study was to evaluate the impact of macrovesicular (MaS) and microvesicular steatosis (MiS) on postoperative liver function in living donors undergoing right hepatectomy. METHODS: We retrospectively reviewed the medical records of 450 living liver donors who underwent right hepatectomy between 2000 and 2009. First, we divided the donors into two groups according to the degree of MaS regardless of MiS: group MaS_5 (n=250), donors with <5% MaS and group MaS_30 (n=200), donors with 5% to 30% MaS. Second, we stratified donors according to the degree of MiS regardless of Mas: group MiS_5 (n=163), donors with <5% MiS, group MiS_30 (n=287), and 5%-30% MiS. We evaluated the peak values of total bilirubin (TB), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) until the thirtieth postoperative day (POD). Next, we assessed the relation between MaS or MiS and postoperative peak liver function tests using regression analysis. RESULTS: Peak values of postoperative AST (227±77 vs 203±67, respectively) and ALT (232±85 vs. 198±72, respectively) were significantly higher in the group MaS_30 than MaS_5. Similarly, the peak values of AST (225±80 vs 194±50, respectively) and ALT (228±85 vs 186±60, respectively) were significantly higher in the group MiS_30 than the group MiS_5. Regression models showed a significant modifying influence of MiS (P<0.001) on postoperative peak ALT levels in addition to MaS (P<.036), suggesting have comparable influences of both MiS and MaS on hepatic injury. CONCLUSION: Our results suggested that a mild degree of either MaS or MiS was associated with higher postoperative peak AST and ALT values. A regression analysis showed both MaS and MiS to display similar impacts on postoperative liver functions after living donor right hepatectomy.


Assuntos
Fígado Gorduroso/diagnóstico , Hepatectomia , Transplante de Fígado , Doadores Vivos , Adulto , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Bilirrubina/sangue , Biomarcadores/sangue , Distribuição de Qui-Quadrado , Ensaios Enzimáticos Clínicos , Fígado Gorduroso/complicações , Feminino , Hepatectomia/efeitos adversos , Humanos , Modelos Lineares , Transplante de Fígado/efeitos adversos , Masculino , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Valor Preditivo dos Testes , Curva ROC , República da Coreia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
20.
J Hum Nutr Diet ; 25(3): 233-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22364496

RESUMO

BACKGROUND: The only treatment for coeliac disease is lifelong adherence to a rigorous gluten-free diet. The present study aimed to evaluate the influence of coeliac disease on the social aspects of daily life of individuals in the U.S.A. METHODS: The present study used a self-administered survey including the standard Quality of Life questionnaire (12-item short-form) with validated disease-specific questions. sas statistical software 2010 (SAS Institute, Cary, NC, U.S.A.) was used to calculate the mean (SD). RESULTS: Individuals with coeliac disease overall had a low positive health perception. Validated diet and disease-specific questions revealed a significant negative impact on quality of life in social settings. Specifically, the areas of travel, dining out and family life are most affected. The negative impact of diet significantly decreased over time, although it did not resolve for the domains of dining out of the home and travel. Those diagnosed in childhood and maintained on the diet had less of an impact on the quality of life as an adult. CONCLUSIONS: Individuals with coeliac disease in the U.S.A. have a diminished quality of life, especially in the social aspects of life.


Assuntos
Doença Celíaca/psicologia , Inquéritos Epidemiológicos , Qualidade de Vida , Adolescente , Adulto , Idoso , Doença Celíaca/dietoterapia , Dieta Livre de Glúten , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Autoimagem , Ajustamento Social , Inquéritos e Questionários , Estados Unidos , Adulto Jovem
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