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1.
J Phys Condens Matter ; 33(19)2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33545697

RESUMO

In recent years, artificial intelligence techniques have proved to be very successful when applied to problems in physical sciences. Here we apply an unsupervised machine learning (ML) algorithm called principal component analysis (PCA) as a tool to analyse the data from muon spectroscopy experiments. Specifically, we apply the ML technique to detect phase transitions in various materials. The measured quantity in muon spectroscopy is an asymmetry function, which may hold information about the distribution of the intrinsic magnetic field in combination with the dynamics of the sample. Sharp changes of shape of asymmetry functions-measured at different temperatures-might indicate a phase transition. Existing methods of processing the muon spectroscopy data are based on regression analysis, but choosing the right fitting function requires knowledge about the underlying physics of the probed material. Conversely, PCA focuses on small differences in the asymmetry curves and works without any prior assumptions about the studied samples. We discovered that the PCA method works well in detecting phase transitions in muon spectroscopy experiments and can serve as an alternative to current analysis, especially if the physics of the studied material are not entirely known. Additionally, we found out that our ML technique seems to work best with large numbers of measurements, regardless of whether the algorithm takes data only for a single material or whether the analysis is performed simultaneously for many materials with different physical properties.

2.
Eur J Nutr ; 59(4): 1517-1527, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31139889

RESUMO

PURPOSE: Diets with increased protein content are popular strategies for body weight regulation, but the effect of such diets for the colonic luminal environment is unclear. We aimed to investigate the associations between putative colorectal cancer-related markers and total protein intake, plant and animal proteins, and protein from red and processed meat in pre-diabetic adults (> 25 years). METHODS: Analyses were based on clinical and dietary assessments at baseline and after 1 year of intervention. Protein intake was assessed from 4-day dietary records. Putative colorectal cancer-related markers identified from 24-h faecal samples collected over three consecutive days were: concentration of short-chain fatty acids, phenols, ammonia, and pH. RESULTS: In total, 79 participants were included in the analyses. We found a positive association between change in total protein intake (slope: 74.72 ± 28.84 µmol per g faeces/E%, p = 0.01), including animal protein intake (slope: 87.63 ± 32.04 µmol per g faeces/E%, p = 0.009), and change in faecal ammonia concentration. For change in ammonia, there was a dose-response trend from the most negative (lowest tertile) to the most positive (highest tertile) association (p = 0.01): in the high tertile, a change in intake of red meat was positively associated with an increase in ammonia excretion (slope: 2.0 ± 0.5 µmol per g faeces/g/day, p < 0.001), whereas no such association was found in the low and medium tertile groups. CONCLUSION: Increases in total and animal protein intakes were associated with higher excretion of ammonia in faeces after 1 year in overweight pre-diabetic adults undertaking a weight-loss intervention. An increase in total or relative protein intake, or in the ratio of animal to plant protein, was not associated with an increase in faeces of any of the other putative colorectal cancer risk markers. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01777893.


Assuntos
Proteínas Animais da Dieta/administração & dosagem , Neoplasias Colorretais/complicações , Neoplasias Colorretais/metabolismo , Sobrepeso/complicações , Proteínas de Plantas/administração & dosagem , Estado Pré-Diabético/metabolismo , Programas de Redução de Peso/métodos , Biomarcadores Tumorais/metabolismo , Estudos de Coortes , Dieta/métodos , Fezes , Feminino , Humanos , Internacionalidade , Masculino , Pessoa de Meia-Idade , Sobrepeso/metabolismo , Sobrepeso/terapia , Fatores de Risco
3.
Arq. bras. med. vet. zootec. (Online) ; 69(5): 1331-1334, set.-out. 2017. ilus
Artigo em Português | LILACS, VETINDEX | ID: biblio-879370

RESUMO

We report the use of a new surgical technique in a male dog affected by extensive stenosis of intrapelvic urethra through a antepubic urethral deviation, as an alternative to prepubic urethrostomy and ablation of the external genitalia. The technique consisted initially of orchiectomy, followed by retroumbilical celiotomy, transverse section of the penis in the pre-scrotal region and transposition of this towards the abdominal cavity by making anastomosis to the prostatic urethra. The dog was evaluated clinically and by urethrography retrograde positive contrast for up to four years after the procedure without any clinical signs, changes in urine stream or stenosis image. It is concluded that the pre-pubic urethral transposition is a viable alternative treatment for this dog affected by extensive stenosis of the membranous urethra.(AU)


Assuntos
Animais , Masculino , Cães , Anastomose Cirúrgica/veterinária , Estreitamento Uretral/cirurgia , Estreitamento Uretral/veterinária , Uretra/cirurgia
4.
Osteoporos Int ; 26(10): 2479-89, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26018090

RESUMO

UNLABELLED: Persistence with and adherence to osteoporosis therapy are critical for fracture reduction. This non-interventional study is evaluating medication-taking behavior of women with postmenopausal osteoporosis (PMO) receiving denosumab in Germany, Austria, Greece, and Belgium. Patients were representative of the PMO population and highly persistent with and adherent to denosumab at 12 months. INTRODUCTION: Persistence with and adherence to osteoporosis therapy are important for optimal treatment efficacy, namely fracture reduction. This ongoing, non-interventional study will evaluate medication-taking behavior of women with postmenopausal osteoporosis (PMO) receiving denosumab in routine practice in four European countries. METHODS: The study enrolled women who had been prescribed subcutaneous denosumab (60 mg every 6 months) in accordance with prescribing information and local guidelines. Persistence was defined as receiving the subsequent injection within 6 months + 8 weeks of the previous injection. Adherence was defined as receiving two consecutive injections within 6 months ± 4 weeks of each other. Medication coverage ratio (MCR) was calculated using the time a patient was covered with denosumab, as assessed from prescription records. Treatment was assigned prior to and independently of enrollment; outcomes are recorded during routine practice. RESULTS: These planned 12-month interim analyses included data from 1500 patients from 141 sites. Mean age was 66.4-72.4 years, mean baseline total hip T-scores ranged from -2.0 to -2.1 and femoral neck T-scores from -2.2 to -2.6, and 30.7-62.1% of patients had prior osteoporotic fracture. Persistence was 87.0-95.3%, adherence 82.7-89.3%, and MCR 91.3-95.4%. In a univariate analysis, increased age, decreased mobility, and increased distance to the clinic were associated with significantly decreased persistence; parental history of hip fracture was associated with significantly increased persistence. CONCLUSIONS: These data extend the real-world evidence regarding persistence with and adherence to denosumab, both of which are critical for favorable clinical outcomes, including fracture risk reduction.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Denosumab/administração & dosagem , Adesão à Medicação/estatística & dados numéricos , Osteoporose Pós-Menopausa/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Conservadores da Densidade Óssea/efeitos adversos , Conservadores da Densidade Óssea/uso terapêutico , Comorbidade , Denosumab/efeitos adversos , Denosumab/uso terapêutico , Esquema de Medicação , Europa (Continente)/epidemiologia , Feminino , Humanos , Injeções Subcutâneas , Medicina/estatística & dados numéricos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/epidemiologia , Osteoporose Pós-Menopausa/psicologia , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/prevenção & controle , Estudos Prospectivos
5.
Nat Commun ; 5: 4504, 2014 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-25060143

RESUMO

The quest for realization of non-Abelian phases of matter, driven by their possible use in fault-tolerant topological quantum computing, has been spearheaded by recent developments in p-wave superconductors. The chiral p(x)+ip(y)-wave superconductor in two-dimensions exhibiting Majorana modes provides the simplest phase supporting non-Abelian quasiparticles and can be seen as the blueprint of fractional topological order. Alternatively, Kitaev's Majorana wire has emerged as an ideal toy model to understand Majorana modes. Here we present a way to make the transition from Kitaev's Majorana wires to two-dimensional p-wave superconductors in a system with cold atomic gases in an optical lattice. The main idea is based on an approach to generate p-wave interactions by coupling orbital degrees of freedom with strong s-wave interactions. We demonstrate how this design can induce Majorana modes at edge dislocations in the optical lattice, and we provide an experimentally feasible protocol for the observation of the non-Abelian statistics.

6.
Allergy ; 69(5): 632-42, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24661001

RESUMO

BACKGROUND: Type 2 immune responses directed by Th2 cells and characterized by the signature cytokines IL4, IL5, and IL13 play major pathogenic roles in atopic diseases. Single nucleotide polymorphisms in the human Th2 cytokine locus in particular in a locus control region within the DNA repair gene RAD50, containing several RAD50 DNase1-hypersensitive sites (RHS), have been robustly associated with atopic traits in genome-wide association studies (GWAS). Functional variants in IL13 have been intensely studied, whereas no causative variants for the IL13-independent RAD50 signal have been identified yet. This study aimed to characterize the functional impact of the atopy-associated polymorphism rs2240032 located in the human RHS7 on cis-regulatory activity and differential binding of transcription factors. METHODS: Differential transcription factor binding was analyzed by electrophoretic mobility shift assays (EMSAs) with Jurkat T-cell nuclear extracts. Identification of differentially binding factors was performed using mass spectrometry (LC-MS/MS). Reporter vector constructs carrying either the major or minor allele of rs2240032 were tested for regulating transcriptional activity in Jurkat and HeLa cells. RESULTS: The variant rs2240032 impacts transcriptional activity and allele-specific binding of SMAD3, SP1, and additional putative protein complex partners. We further demonstrate that rs2240032 is located in an RHS7 subunit which itself encompasses repressor activity and might be important for the fine-tuning of transcription regulation within this region. CONCLUSION: The human RHS7 critically contributes to the regulation of gene transcription, and the common atopy-associated polymorphism rs2240032 impacts transcriptional activity and transcription factor binding.


Assuntos
Citocinas/genética , Regulação da Expressão Gênica , Hipersensibilidade Imediata/genética , Hipersensibilidade Imediata/metabolismo , Região de Controle de Locus Gênico , Proteína Smad3/metabolismo , Fator de Transcrição Sp1/metabolismo , Células Th2/metabolismo , Transcrição Gênica , Alelos , Sítios de Ligação , Ordem dos Genes , Humanos , Hipersensibilidade Imediata/imunologia , Desequilíbrio de Ligação , Motivos de Nucleotídeos , Polimorfismo de Nucleotídeo Único , Matrizes de Pontuação de Posição Específica , Regiões Promotoras Genéticas , Ligação Proteica , Sequências Reguladoras de Ácido Nucleico
7.
Clin Exp Allergy ; 44(4): 517-28, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24261983

RESUMO

BACKGROUND: Regulatory B cells have been identified that strongly reduce allergic and auto-immune inflammation in experimental models by producing IL-10. Recently, several human regulatory B-cell subsets with an impaired function in auto-immunity have been described, but there is no information on regulatory B cells in allergic asthma. OBJECTIVE: In this study, the frequency and function of IL-10 producing B-cell subsets in allergic asthma were investigated. METHODS: Isolated peripheral blood B cells from 13 patients with allergic asthma and matched healthy controls were analyzed for the expression of different regulatory B-cell markers. Next, the B cells were activated by lipopolysaccharide (LPS), CpG or through the B-cell receptor, followed by co-culture with endogenous memory CD4(+) T cells and house dust mite allergen DerP1. RESULTS: Lower number of IL-10 producing B cells were found in patients in response to LPS, however, this was not the case when B cells were activated through the B-cell receptor or by CpG. Further dissection showed that only the CD24(hi)CD27(+) B-cell subset was reduced in number and IL-10 production to LPS. In response to DerP1, CD4(+) T cells from patients co-cultured with LPS-primed total B cells produced less IL-10 compared to similar cultures from controls. These results are in line with the finding that sorted CD24(hi)CD27(+) B cells are responsible for the induction of IL-10(+) CD4(+) T cells. CONCLUSIONS: Taken together, these data indicate that CD24(hi)CD27(+) B cells from allergic asthma patients produce less IL-10 in response to LPS leading to a weaker IL-10 induction in T cells in response to DerP1, which may play a role in allergic asthma.


Assuntos
Asma/imunologia , Subpopulações de Linfócitos B/imunologia , Adulto , Asma/fisiopatologia , Subpopulações de Linfócitos B/metabolismo , Antígeno CD24/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Imunofenotipagem , Interleucina-10/metabolismo , Lipopolissacarídeos/imunologia , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Fenótipo , Testes de Função Respiratória , Fatores de Risco , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Receptor 4 Toll-Like/metabolismo , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo , Adulto Jovem
8.
J Intern Med ; 274(5): 425-39, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24127940

RESUMO

BACKGROUND: Metabolomics is a versatile unbiased method to search for biomarkers of human disease. In particular, one approach in cancer therapy is to promote apoptosis in tumour cells; this could be improved with specific biomarkers of apoptosis for monitoring treatment. We recently observed specific metabolic patterns in apoptotic cell lines; however, in that study, apoptosis was only induced with one pro-apoptotic agent, staurosporine. OBJECTIVE: The aim of this study was to find novel biomarkers of apoptosis by verifying our previous findings using two further pro-apoptotic agents, 5-fluorouracil and etoposide, that are commonly used in anticancer treatment. METHODS: Metabolic parameters were assessed in HepG2 and HEK293 cells using the newborn screening assay adapted for cell culture approaches, quantifying the levels of amino acids and acylcarnitines with mass spectrometry. RESULTS: We were able to identify apoptosis-specific changes in the metabolite profile. Moreover, the amino acids alanine and glutamate were both significantly up-regulated in apoptotic HepG2 and HEK293 cells irrespective of the apoptosis inducer. CONCLUSION: Our observations clearly indicate the potential of metabolomics in detecting metabolic biomarkers applicable in theranostics and for monitoring drug efficacy.


Assuntos
Apoptose/genética , Linhagem Celular Tumoral/metabolismo , Metabolômica , Medicina de Precisão/métodos , Alanina/análise , Aminoácidos/análise , Apoptose/efeitos dos fármacos , Biomarcadores/metabolismo , Carnitina/análogos & derivados , Carnitina/análise , Caspase 3/metabolismo , Caspase 7/metabolismo , Linhagem Celular Tumoral/química , Linhagem Celular Tumoral/efeitos dos fármacos , Etoposídeo/farmacologia , Análise de Injeção de Fluxo , Fluoruracila/farmacologia , Ácido Glutâmico/análise , Células HEK293/química , Células HEK293/efeitos dos fármacos , Células HEK293/metabolismo , Células Hep G2/química , Células Hep G2/efeitos dos fármacos , Células Hep G2/metabolismo , Humanos , Metabolômica/métodos
9.
Phys Rev Lett ; 108(25): 256809, 2012 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-23004638

RESUMO

We study interacting bosons on a lattice in a magnetic field. When the number of flux quanta per plaquette is close to a rational fraction, the low-energy physics is mapped to a multispecies continuum model: bosons in the lowest Landau level where each boson is given an internal degree of freedom, or pseudospin. We find that the interaction potential between the bosons involves terms that do not conserve pseudospin, corresponding to umklapp processes, which in some cases can also be seen as BCS-type pairing terms. We argue that in experimentally realistic regimes for bosonic atoms in optical lattices with synthetic magnetic fields, these terms are crucial for determining the nature of allowed ground states. In particular, we show numerically that certain paired wave functions related to the Moore-Read Pfaffian state are stabilized by these terms, whereas certain other wave functions can be destabilized when umklapp processes become strong.

10.
Hum Reprod ; 27(10): 2955-65, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22859507

RESUMO

BACKGROUND: Current non-invasive diagnostic methods for endometriosis lack sensitivity and specificity. In search for new diagnostic biomarkers for ovarian endometriosis, we used a hypothesis-generating targeted metabolomics approach. METHODS: In a case-control study, we collected plasma of study participants and analysed their metabolic profiles. We selected a group of 40 patients with ovarian endometriosis who underwent laparoscopic surgery and a control group of 52 healthy women who underwent sterilization at the University Clinical Centre Ljubljana, Slovenia. Over 140 targeted analytes included glycerophospholipids, sphingolipids and acylcarnitines. The analytes were quantified by electrospray ionization tandem mass spectrometry. For assessing the strength of association between the metabolite or metabolite ratios and the disease, we used crude and adjusted odds ratios. A stepwise logistic regression procedure was used for selecting the best combination of biomarkers. RESULTS: Eight lipid metabolites were identified as endometriosis-associated biomarkers due to elevated levels in patients compared with controls. A model containing hydroxysphingomyelin SMOH C16:1 and the ratio between phosphatidylcholine PCaa C36:2 to ether-phospholipid PCae C34:2, adjusted for the effect of age and the BMI, resulted in a sensitivity of 90.0%, a specificity of 84.3% and a ratio of the positive likelihood ratio to the negative likelihood ratio of 48.3. CONCLUSIONS: Our results suggest that endometriosis is associated with elevated levels of sphingomyelins and phosphatidylcholines, which might contribute to the suppression of apoptosis and affect lipid-associated signalling pathways. Our findings suggest novel potential routes for therapy by specifically blocking highly up-regulated isoforms of phosphpolipase A2 and lysophosphatidylcholine acyltransferase 4.


Assuntos
Endometriose/diagnóstico , Fosfatidilcolinas/sangue , Esfingomielinas/sangue , Adulto , Fatores Etários , Biomarcadores/sangue , Índice de Massa Corporal , Estudos de Casos e Controles , Endometriose/sangue , Feminino , Humanos , Funções Verossimilhança , Modelos Logísticos , Sensibilidade e Especificidade
11.
Eur J Vasc Endovasc Surg ; 44(2): 153-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22705161

RESUMO

OBJECTIVES: It is currently unclear whether the parallels between abdominal aortic aneurysms (AAAs) and chronic obstructive pulmonary disease (COPD) are explained by common risk factors alone, such as cigarette smoking, or by a predetermined cause. Given the persistent controversy with regard to the association between AAA and COPD, we studied this association in depth. METHODS: We conducted a case-control study comparing patients with a small AAA (maximum infrarenal diameter 35-50 mm, n = 221) with controls diagnosed with peripheral artery disease (PAD, n = 87). The controls were matched to the cases for lifetime cigarette smoking. Pulmonary function was measured by spirometry, and all subjects completed a questionnaire on medical history and smoking habits (current, former and never smokers). RESULTS: Aneurysm patients were similar to controls with respect to gender (p = 0.71), lifetime cigarette smoking (39 vs. 34 pack years, p = 0.23) and history of cardiovascular disease (45% vs. 55%, p = 0.12). Aneurysm patients had more airway obstruction (forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) (0.69 ± 0.12 vs. 0.78 ± 0.11, p < 0.001)), which was most pronounced in never smokers (0.73 ± 0.07 vs. 0.86 ± 0.07, p < 0.001). COPD was more prevalent in aneurysm patients (44%; 98/221) than in controls (20%; 17/87) (adjusted odds ratio (OR) 3.0; 95% confidence interval (95%CI) 1.6-5.5, p < 0.001). In particular, a major proportion of AAA patients was newly diagnosed with COPD; only 40 of 98 patients (41%) with COPD (mild, moderate or severe/very severe) were known before with obstructive pulmonary defects and received treatment. CONCLUSIONS: This study confirms an association between AAA and COPD and shows that this association is independent from smoking. Findings also demonstrate that COPD is under-diagnosed in AAA patients.


Assuntos
Aneurisma da Aorta Abdominal/epidemiologia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Fumar/epidemiologia , Idoso , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/tratamento farmacológico , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Doxiciclina/uso terapêutico , Feminino , Volume Expiratório Forçado , Humanos , Modelos Lineares , Modelos Logísticos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Países Baixos/epidemiologia , Razão de Chances , Prevalência , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Medição de Risco , Fatores de Risco , Espirometria , Inquéritos e Questionários , Ultrassonografia , Capacidade Vital
12.
Phys Rev Lett ; 108(4): 045306, 2012 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-22400857

RESUMO

We study correlated phases occurring in the flat lowest band of the dice-lattice model at flux density one-half. We discuss how to realize this model, also referred to as the T(3) lattice, in cold atomic gases. We construct the projection of the model to the lowest dice band, which yields a Hubbard Hamiltonian with interaction-assisted hopping processes. We solve this model for bosons in two limits. In the limit of large density, we use Gross-Pitaevskii mean-field theory to reveal time-reversal symmetry breaking vortex lattice phases. At low density, we use exact diagonalization to identify three stable phases at fractional filling factors ν of the lowest band, including a classical crystal at ν = 1/3, a supersolid state at ν = 1/2, and a Mott insulator at ν = 1.

13.
Osteoporos Int ; 22(4): 1227-36, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20628731

RESUMO

UNLABELLED: European observational 1-year study assessed osteoporosis and fracture patterns in 3,402 postmenopausal women prescribed osteoporosis medication. Almost 40% of patients had a previous fracture, while 25% had neither fracture nor dual energy X-ray absorptiometry (DXA) diagnosis and were prescribed medication, probably due to other risk factors. INTRODUCTION: This analysis assessed osteoporosis and fracture prevalence in postmenopausal women prescribed osteoporosis treatment in the Prospective Observational Study Investigating Bone Loss Experience in Europe(POSSIBLE EU). METHODS: Women in this observational, multicenter 1-year study were categorized by fracture history and location at baseline. Baseline characteristics were analyzed according to no DXA and DXA diagnosis (osteoporosis or osteopenia). Fractures occurring during the 1-year follow-up period were recorded. RESULTS: Of the 3,402 women enrolled, 39% had a previous fracture, of whom 30% had ≥ 2 fractures. One thousand seven hundred and eighty-four (52%) patients had a DXA diagnosis (osteoporosis 68%, osteopenia 31%, and unknown 1%). Among the osteoporosis patients, 37% had a previous fracture (hip 2.9%, vertebral 8.8%, and non-hip, non-vertebral 25%) and 35% had fractures associated with major trauma. Of the 3,402 women, 1,476 (43%) had no DXA diagnosis; of these, 57% had no fracture (25% of all women). Risk factors varied across patients with and without DXA diagnosis. During the 1-year follow-up period, the fracture incidence in patients with or without a previous fracture at baseline was 4.7% and 1.6%, respectively. CONCLUSION: Almost 40% of patients prescribed osteoporosis medication had a previous fracture, highlighting a population with advanced disease. In contrast, 25% of patients had neither a previous fracture nor DXA diagnosis and were prescribed treatment, probably due to other risk factors. There is a need for continued improvement of disease management in European women.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Osteoporose Pós-Menopausa/epidemiologia , Fraturas por Osteoporose/epidemiologia , Absorciometria de Fóton , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Métodos Epidemiológicos , Europa (Continente)/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/tratamento farmacológico , Osteoporose Pós-Menopausa/etiologia , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/prevenção & controle
14.
Respir Med ; 104(4): 557-63, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19906520

RESUMO

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is an inflammatory condition characterized by oxidative stress and the formation of volatile organic compounds (VOCs) secreted via the lungs. We recently developed a methodological approach able to identify profiles of VOCs in breath unique for patient groups. Here we applied this recently developed methodology regarding diagnosis of COPD patients. METHODS: Fifty COPD patients and 29 controls provided their breath and VOCs were analyzed by gas chromatography-mass spectrometry to identify relevant VOCs. An additional 16 COPD patients and 16 controls were sampled in order to validate the model, and 15 steroid naïve COPD patients were sampled to determine whether steroid use affects performance. FINDINGS: 1179 different VOCs were detected, of which 13 were sufficient to correctly classify all 79 subjects. Six of these 13 VOCs classified 92% of the subjects correctly (sensitivity: 98%, specificity: 88%) and correctly classified 29 of 32 subjects (sensitivity: 100%, specificity: 81%) from the independent validation population. Fourteen out of 15 steroid naïve COPD patients were correctly classified thus excluding treatment influences. INTERPRETATION: This is the first study distinguishing COPD subjects from controls solely based on the presence of VOCs in breath. Analysis of VOCs might be highly relevant for diagnosis of COPD.


Assuntos
Doença Pulmonar Obstrutiva Crônica/diagnóstico , Compostos Orgânicos Voláteis/análise , Corticosteroides/uso terapêutico , Idoso , Biomarcadores/análise , Testes Respiratórios/métodos , Estudos de Casos e Controles , Expiração , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/metabolismo , Sensibilidade e Especificidade
15.
Phys Rev Lett ; 103(10): 105303, 2009 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-19792327

RESUMO

We study the ground states of the Bose-Hubbard model in a uniform magnetic field, motivated by the physics of cold atomic gases on lattices at high vortex density. Mapping the bosons to composite fermions (CF) leads to the prediction of quantum Hall fluids that have no counterpart in the continuum. We construct trial states for these phases and test numerically the predictions of the CF model. We establish the existence of strongly correlated phases beyond those in the continuum limit and provide evidence for a wider scope of the composite fermion approach beyond its application to the lowest Landau level.

16.
Thorax ; 64(1): 26-32, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18835960

RESUMO

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterised by an abnormal inflammatory reaction of the lungs involving activation of epithelial cells. Leptin is a pleiotropic cytokine important in the regulation of immune responses via its functional receptor Ob-Rb. This study was undertaken to test the hypothesis that severe COPD is associated with increased leptin expression in epithelial cells. METHODS: Immunohistochemistry for leptin was performed on peripheral lung specimens from 20 patients with COPD (GOLD stage 4), 14 asymptomatic ex-smokers and 13 never smokers. Leptin and Ob-Rb mRNA expression were determined by rtPCR in cultured primary bronchial epithelial cells and primary type II pneumocytes. NCI-H292 and A549 cell lines were used to study functional activation of leptin signalling. RESULTS: Leptin immunoreactivity in lung tissue was observed in bronchial epithelial cells, type II pneumocytes, macrophages (tissue/alveolar) and interstitial lymphocytic infiltrates. rtPCR analysis confirmed pulmonary leptin and Ob-Rb mRNA expression in primary bronchial epithelial cells and pneumocytes. Leptin-expressing bronchial epithelial cells and alveolar macrophages were markedly higher in patients with severe COPD and ex-smokers than in never smokers (p<0.02). Exposure of cultured primary bronchial epithelial cells to smoke resulted in increased expression of both leptin and Ob-Rb (p<0.05). Leptin induced phosphorylation of STAT3 in both NCI-H292 and A549 cells. CONCLUSIONS: Leptin expression is increased in bronchial epithelial cells and alveolar macrophages of ex-smokers with or without severe COPD compared with never smokers. A functional leptin signalling pathway is present in lung epithelial cells.


Assuntos
Leptina/metabolismo , Pulmão/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Receptores para Leptina/metabolismo , Fumar/metabolismo , Western Blotting , Brônquios/metabolismo , Brônquios/patologia , Células Cultivadas , Células Epiteliais/metabolismo , Feminino , Volume Expiratório Forçado/fisiologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/patologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , RNA Mensageiro/metabolismo , Capacidade Vital/fisiologia
17.
Water Environ Res ; 80(3): 238-47, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18419012

RESUMO

This work examines the performance of a hydrous ferric oxide (HFO) reactive filtration (RF) process with coupled chemically enhanced secondary treatment (RECYCLE) for phosphorus removal from municipal wastewater (HFO-RF-RECYCLE). A 3-month, 0.95-ML/d (0.25-mgd) demonstration of HFO-RF-RECYCLE was performed at a municipal wastewater treatment plant equipped with oxidation ditches and secondary clarifiers. Influent to the plant averaged 6.0 mg/L phosphorus, with a tertiary effluent average of 0.011 mg/L phosphorus. Iron doses to the plant were low, at 5 mg/L. Inline recycling of HFO solution rejects to the plant influent resulted in a maximum 90.3%, dose-dependent reduction of phosphorus in the secondary effluent at 4.5 ML/d (1.2 mgd). Other results included reduction of total suspended solids and turbidity. A mass balance analysis was performed. We conclude that HFO-RF-RECYCLE may allow very low levels of phosphorus discharge from municipal wastewater treatment plants with a ferric-iron-based tertiary filtration process and residual recycling.


Assuntos
Filtração/métodos , Fósforo/química , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Reatores Biológicos , Cidades , Compostos Férricos/química , Humanos , Ferro/química
18.
Water Environ Res ; 80(3): 248-56, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18419013

RESUMO

The removal mechanism of a hydrous ferric oxide (HFO) reactive filtration (RF) process with coupled chemically enhanced secondary treatment (RECYCLE) for phosphorus removal from municipal wastewater (HFO-RF-RECYCLE) was examined. A 0.95-ML/d (0.25-mgd) demonstration of HFO-RF-RECYCLE was performed at a municipal wastewater treatment plant equipped with oxidation ditches and secondary clarifiers. Influent to the plant averaged 6.0 mg/L phosphorus, with a 3-month tertiary effluent average of 0.011 mg/L phosphorus. In addition to aqueous geochemical modeling, experiments with surface charge, scanning electron microscopy, adsorptive capacity, thermal desorption, and most probable number of iron(III)-reducing bacteria were performed on samples from the system, to determine the major phosphorus-removal pathways. Results suggest that, in addition to filtration of particulate phosphorus, the low tertiary effluent total phosphorus result was achieved by adsorption.


Assuntos
Filtração/métodos , Fósforo , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Adsorção , Biodegradação Ambiental , Reatores Biológicos , Cidades , Compostos Férricos/química , Humanos , Ferro/química , Ferro/metabolismo , Fósforo/química , Fósforo/farmacocinética
20.
Artigo em Inglês | MEDLINE | ID: mdl-18055279

RESUMO

Analysis of exhaled air leads to the development of fast accurate and non-invasive diagnostics. A comprehensive analysis of the entire range of volatile organic compounds (VOCs) in exhaled air samples will enable the identification of VOCs unique for certain patient groups. This study demonstrates proof of principle of our developed method tested on a smoking/non-smoking study population. Thermal desorption and gas chromatography coupled to time-of-flight mass spectrometry were used to analyse exhaled air samples. The VOC profiles obtained from each individual were combined into one final database based on similarity of mass spectra and retention indexes (RI), which offers the possibility for a reliable selection of compounds of interest. As proof of principle we correctly classified all subjects from population of smoking (N=11) and non-smoking (N=11) based on the VOC profiles available in their exhaled air. Support vector machine (SVM) analysis identified 4 VOCs as biomarkers of recent exposure to cigarette smoke: 2,5-dimethyl hexane, dodecane, 2,5-dimethylfuran and 2-methylfuran. This approach contributes to future development of fast, accurate and non-invasive diagnostics of inflammatory diseases including pulmonary diseases.


Assuntos
Compostos Orgânicos/análise , Adulto , Alcanos/análise , Alcanos/química , Testes Respiratórios/métodos , Feminino , Furanos/análise , Furanos/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Orgânicos/química , Reprodutibilidade dos Testes , Fumar/metabolismo , Volatilização
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