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1.
Foods ; 11(5)2022 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-35267393

RESUMO

In Italy, most of the cultivated walnuts belong to the Sorrento ecotype, and they are considered commercially valuable due to their specific organoleptic characteristics. The aim of this study is to evaluate and compare the morphological and compositional characteristics of walnuts sampled from 'Sorrento' trees cultivated in different locations in Campania and trees of both the 'Chandler' and 'Sorrento' varieties derived from the same location. The results demonstrated that 'Sorrento' and 'Chandler' walnuts have different biometric characteristics and a different fat content, with the highest fat content being found in the 'Sorrento' variety. Regarding the fatty acid (FA) composition, the content of monounsaturated and saturated fatty acids (MUFAs and SFAs) was highest in the 'Sorrento' variety (from 13 to 15% for MUFAs and from 11 to 13% for SFAs), while the polyunsaturated fatty acids (PUFAs) content was highest in the 'Chandler' variety (77%). The total phenolics content (TPC) was highest in the 'Sorrento' variety (from 910 to 1230 mg GAE/100 g), while no difference in γ-tocopherol content was found. Furthermore, the influence of walnut area cultivation was shown for fat content, FA composition and TPC. Therefore, both walnut varieties demonstrated good nutritional properties considering the PUFAs and γ-tocopherol content.

2.
Sci Rep ; 12(1): 1573, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35091643

RESUMO

NbRe-based superconducting thin films recently received relevant interest in the field of low-temperature electronics. However, for these materials the electrical conduction mechanisms, in particular in the normal state, still need to be investigated in more detail. Here, NbRe and NbReN films of different thicknesses have been deposited on two different substrates, namely monocrystalline Si and [Formula: see text] buffered Si. The films were characterized by DC electrical transport measurements. Moreover, a connection with the charge carriers fluctuation processes has been made by analyzing the electrical noise generated in the normal state region. Despite the films morphology seems not to be affected by the substrate used, a lower noise level has been found for the ones grown on [Formula: see text], in particular for NbReN. From this study it emerges that both NbRe and NbReN ultrathin films are of very good quality, as far as the low-temperature electrical noise and conduction are concerned, with noise levels competitive with NbN. These results may further support the proposal of using these materials in a nanowire form in the field of superconducting electronics.

3.
Food Control ; 126: 108085, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34345121

RESUMO

Attention to urban agriculture (UA) has recently grown among practitioners, scientists, and the public, resulting in several initiatives worldwide. Despite the positive perception of modern UA and locally grown, fresh produce, the potential food safety risks connected to these practices may be underestimated, leading to regulatory gaps. Thus, there is a need for assessment tools to evaluate the food safety risks connected to specific UA initiatives, to assist practitioners in self-evaluation and control, and to provide policy makers and scholars a means to pursue and assess food safety in city regions, avoiding either a lack or an excess of regulation that could ultimately hinder the sector. To address this aim, this paper reviews the most recent and relevant literature on UA food safety assessments. Food safety indicators were identified first. Then, a food safety assessment framework for UA initiatives was developed. The framework uses business surveys and food analyses (if available) as a data source for calculating a food safety index for single UA businesses and the whole UA landscape of a given city region. The proposed framework was designed to allow its integration into the CRFS (City Region Food System) toolkit developed by FAO (Food and Agriculture Organization of the United Nations), RUAF foundation (Resource Centres on Urban Agriculture and Food Security) and Wilfrid Laurier University.

4.
Nanotechnology ; 28(46): 465301, 2017 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-29053470

RESUMO

Superconducting NbN nanonetworks with a very small number of interconnected nanowires, with diameter of the order of 4 nm, are fabricated combining a bottom-up (use of porous silicon nanotemplates) with a top-down technique (high-resolution electron beam lithography). The method is easy to control and allows the fabrication of devices, on a robust support, with electrical properties close to a one-dimensional superconductor that can be used fruitfully for novel applications.

5.
Int J Immunopathol Pharmacol ; 28(4): 443-51, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26526203

RESUMO

In addition to the well-known involvement of macrophages and neutrophils, other cell types have been recently reported to substantially contribute to the onset and progression of inflammatory bowel diseases (IBD). Enteric glial cells (EGC) are the equivalent cell type of astrocyte in the central nervous system (CNS) and share with them many neurotrophic and neuro-immunomodulatory properties. This short review highlights the role of EGC in IBD, describing the role played by these cells in the maintenance of gut homeostasis, and their modulation of enteric neuronal activities. In pathological conditions, EGC have been reported to trigger and support bowel inflammation through the specific over-secretion of S100B protein, a pivotal neurotrophic factor able to induce chronic inflammatory changes in gut mucosa. New pharmacological tools that may improve the current therapeutic strategies for inflammatory bowel diseases (IBD), lowering side effects (i.e. corticosteroids) and costs (i.e. anti-TNFα monoclonal antibodies) represent a very important challenge for gastroenterologists and pharmacologists. Novel drugs capable to modulate enteric glia reactivity, limiting the pro-inflammatory release of S100B, may thus represent a significant innovation in the field of pharmacological interventions for inflammatory bowel diseases.


Assuntos
Doenças Inflamatórias Intestinais/etiologia , Intestinos/inervação , Neuroglia/fisiologia , Animais , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Neuroglia/efeitos dos fármacos , Óxido Nítrico/fisiologia , Subunidade beta da Proteína Ligante de Cálcio S100/fisiologia
6.
Sci Rep ; 5: 10705, 2015 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-26024506

RESUMO

Two-dimensional materials, such as graphene, topological insulators, and two-dimensional electron gases, represent a technological playground to develop coherent electronics. In these systems, quantum interference effects, and in particular weak localization, are likely to occur. These coherence effects are usually characterized by well-defined features in dc electrical transport, such as a resistivity increase and negative magnetoresistance below a crossover temperature. Recently, it has been shown that in magnetic and superconducting compounds, undergoing a weak-localization transition, a specific low-frequency 1/f noise occurs. An interpretation in terms of nonequilibrium universal conductance fluctuations has been given. The universality of this unusual electric noise mechanism has been here verified by detailed voltage-spectral density investigations on ultrathin copper films. The reported experimental results validate the proposed theoretical framework, and also provide an alternative methodology to detect weak-localization effects by using electric noise spectroscopy.

7.
Nanotechnology ; 25(42): 425205, 2014 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-25277511

RESUMO

Magnetoresistance oscillations were observed on networks of superconducting ultrathin Nb nanowires presenting evidence of either thermal or quantum activated phase slips. The magnetic transport data, discussed in the framework of different scenarios, reveal that the system behaves coherently in the temperature range where the contribution of the fluctuations is important.

8.
Neurogastroenterol Motil ; 26(8): 1131-43, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24861242

RESUMO

BACKGROUND: Correct neuronal identification is essential to study neurons in health and disease. Although commonly used as pan-neuronal marker, HuC/D's expression pattern varies substantially between healthy and (patho)physiological conditions. This heterogenic labeling has received very little attention. We sought to investigate the subcellular HuC/D localization in enteric neurons in different conditions. METHODS: The localization of neuronal RNA-binding proteins HuC/D was investigated by immunohistochemistry in the mouse myenteric plexus using different toxins and caustic agents. Preparations were also stained with Sox10 and glial fibrillary acidic protein (GFAP) antibodies to assess enteric glial cell appearance. KEY RESULTS: Mechanically induced tissue damage, interference with the respiratory chain and oxygen (O2 ) deprivation increased nuclear HuC/D immunoreactivity. This effect was paralleled by a distortion of the GFAP-labeled glial network along with a loss of Sox10 expression and coincided with the activation of a non-apoptotic genetic program. Chemically induced damage and specific noxious stimuli did not induce a change in HuC/D immunoreactivity, supporting the specific nature of the nuclear HuC/D localization. CONCLUSIONS & INFERENCES: HuC/D is not merely a pan-neuronal marker but its subcellular localization also reflects the condition of a neuron at the time of fixation. The functional meaning of this change in HuC/D localization is not entirely clear, but disturbance in O2 supply in combination with the support of enteric glial cells seems to play a crucial role. The molecular consequence of changes in HuC/D expression needs to be further investigated.


Assuntos
Proteínas ELAV/metabolismo , Plexo Mientérico/metabolismo , Neurônios/metabolismo , Animais , Hipóxia Celular , Colo/inervação , Colo/metabolismo , Proteína Semelhante a ELAV 3 , Proteína Semelhante a ELAV 4 , Proteína Glial Fibrilar Ácida/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Plexo Mientérico/patologia , Neuroglia/metabolismo , Neurônios/patologia
9.
Neurogastroenterol Motil ; 25(2): e151-60, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23279281

RESUMO

BACKGROUND: The intimate association between glial cells and neurons within the enteric nervous system has confounded careful examination of the direct responsiveness of enteric glia to different neuroligands. Therefore, we aimed to investigate whether neurotransmitters known to elicit fast excitatory potentials in enteric nerves also activate enteric glia directly. METHODS: We studied the effect of acetylcholine (ACh), serotonin (5-HT), and adenosine triphosphate (ATP) on intracellular Ca(2+) signaling using aequorin-expressing and Fluo-4 AM-loaded CRL-2690 rat and human enteric glial cell cultures devoid of neurons. The influence of these neurotransmitters on the proliferation of glia was measured and their effect on the expression of c-Fos as well as glial fibrillary acidic protein (GFAP), Sox10, and S100 was examined by immunohistochemistry and quantitative RT-PCR. KEY RESULTS: Apart from ATP, also ACh and 5-HT induced a dose-dependent increase in intracellular Ca(2+) concentration in CRL-2690 cells. Similarly, these neurotransmitters also evoked Ca(2+) transients in human primary enteric glial cells obtained from mucosal biopsies. In contrast with ATP, stimulation with ACh and 5-HT induced early gene expression in CRL-2690 cells. The proliferation of enteric glia and their expression of GFAP, Sox10, and S100 were not affected following stimulation with these neurotransmitters. CONCLUSIONS & INFERENCES: We provide evidence that enteric glial cells respond to fast excitatory neurotransmitters by changes in intracellular Ca(2+). On the basis of our experimental in vitro setting, we show that enteric glia are not only directly responsive to purinergic but also to serotonergic and cholinergic signaling mechanisms.


Assuntos
Sistema Nervoso Entérico/fisiologia , Neuroglia/metabolismo , Neurotransmissores/metabolismo , Transmissão Sináptica/fisiologia , Animais , Cálcio/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Sistema Nervoso Entérico/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Neuroglia/efeitos dos fármacos , Neurotransmissores/farmacologia , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Transmissão Sináptica/efeitos dos fármacos
10.
Neurogastroenterol Motil ; 25(1): 31-8.e2-3, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22908903

RESUMO

BACKGROUND: Mental stress (MS) may alter gastric sensory-motor function. The aim of the study was to assess postprandial autonomic nervous system activity and stress hormones in response to acute mental stress in dyspeptic patients. METHODS: A total of 25 patients with postprandial distress syndrome (PDS; 11 mol L(-1), age 35.9 ± 9.3 years) and 12 healthy controls (5 mol L(-1), age 25.8 ± 4.6 years) underwent electrogastrography and (13) C-octanoate gastric emptying study using a 480 kcal solid meal. Heart rate variability (LF/HF ratio) and corticotrophin-releasing factor, adrenocorticotropic hormone (ACTH), and cortisol serum levels were also evaluated. Dyspeptic symptoms were scored by analogue visual scale and expressed as symptoms total score (TS). The protocol was repeated twice in each subject, with and without a mental stress test before the meal. KEY RESULTS: Mental stress significantly increased postprandial symptoms severity in patients (TS: stress 111 ± 18 vs basal 50 ± 10; P < 0.05). Low-/high-frequency component ratio was significantly higher in patients after MS at 120 min (stress 5.46 ± 0.41 vs basal 3.41 ± 0.64; P < 0.01) and 180 min (stress 5.29 ± 0.2 vs basal 3.58 ± 0.19; P < 0.05). During stress session, in patients we found a significantly higher ACTH level than baseline at 30, 60, 90, 150, 210, 240, and 270 min and a significantly higher cortisol level at 30, 60, 90, 120, 210, and 270 min. Gastric emptying rate and electrical activity were not influenced by MS. CONCLUSIONS & INFERENCES: In PDS patients, administration of MS before meal increases symptoms severity by inducing sympathetic hyperactivity and increased stress hormones levels. As the gastric emptying looks not altered, we conclude that these neurohormonal responses mainly affect sensitive function.


Assuntos
Dispepsia/fisiopatologia , Dispepsia/psicologia , Estresse Psicológico/complicações , Sistema Nervoso Simpático/fisiopatologia , Hormônio Adrenocorticotrópico/sangue , Adulto , Hormônio Liberador da Corticotropina/sangue , Dispepsia/sangue , Feminino , Esvaziamento Gástrico/fisiologia , Humanos , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/fisiopatologia , Masculino , Complexo Mioelétrico Migratório/fisiologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Período Pós-Prandial/fisiologia , Síndrome
11.
Neurogastroenterol Motil ; 23(9): e372-82, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21762414

RESUMO

BACKGROUND: Enteric glial cells (EGCs) have been recently indicated as key regulators of intestinal inflammation in animals. Whether or not this is true and how these cells participate to inflammatory responses in humans is unknown. METHODS: We isolated primary EGCs from human small bowel and then, we purified and characterized those using specific glial markers, such as S100B and glial fibrillary acidic protein (GFAP). To mimic an inflammatory scenario, we exposed EGCs to exogenous stimuli, such as lipopolysaccharide and interferon-gamma (LPS and IFN-γ), alone or in combination, to evaluate glial activation [measuring GFAP, S100B level together with c-fos, major histocompatibility complex (MHC) class II, inducible nitric oxide (iNOS) proteins expression and nitric oxide (NO) production] and proliferation, respectively. KEY RESULTS: We showed that, when challenged with a combination of LPS and IFN-γ, EGCs are significantly activated, as indicated by their positivity to c-fos and MHC class II. Similarly, pro-inflammatory stimuli significantly increase the cell proliferation rate, the expression of both S100B and GFAP, and the NO production consequent to the induction of EGCs-derived iNOS protein, with the last being dependent on S100B-RAGE (receptor for advanced glycation endproducts) interaction. CONCLUSIONS & INFERENCES: Our data provide the first evidence that human EGCs directly respond to pro-inflammatory stimuli by changing their expression profile and by proliferating. The finding that stimulated EGCs are able to produce NO points to a role of this cell population in the scenario of intestinal inflammation.


Assuntos
Comunicação Autócrina/fisiologia , Sistema Nervoso Entérico/citologia , Inflamação/metabolismo , Neuroglia/metabolismo , Óxido Nítrico/biossíntese , Animais , Biomarcadores/metabolismo , Proliferação de Células , Células Cultivadas , Feminino , Genes MHC da Classe II , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Interferon gama/farmacologia , Lipopolissacarídeos/farmacologia , Masculino , Pessoa de Meia-Idade , Fatores de Crescimento Neural/metabolismo , Neuroglia/citologia , Neuroglia/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Subunidade beta da Proteína Ligante de Cálcio S100 , Proteínas S100/metabolismo
12.
Minerva Endocrinol ; 36(4): 311-24, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22322654

RESUMO

Serotonin is one of the most abundant molecules in the gastrointestinal tract and it plays a crucial role in the regulation of several physiological functions, such as motility, secretion and visceral sensitivity. Besides this well documented physiological role, increasing evidence supports the concept that 5-HT is directly involved in pathological mechanisms, as well as the modulation of immune/inflammatory responses within the gut. The wide range of pathophysiological actions exerted by 5-HT are mediated by several different serotonergic receptor types and subtypes. Depending on the receptor bound and its localization, 5-HT evokes different and, sometimes, opposite responses. Therapeutic interventions aiming at modulating 5-HT signaling are mainly focused on the development of receptor agonists/antagonists, characterized by high affinity and selectivity for serotonergic receptors in the gut, to avoid the presence of adverse effects in the brain, where 5-HT is important in control mood. This review summarizes the vast current knowledge on 5-HT as a physiological mediator and analyzes the increasing body of literature describing 5-HT signaling abnormalities in functional and inflammatory disorders both in animal models and in humans. Finally, an overview on the therapeutic agents used in clinical practice is provided.


Assuntos
Gastroenteropatias/fisiopatologia , Trato Gastrointestinal/fisiologia , Serotonina/fisiologia , Animais , Constipação Intestinal/fisiopatologia , Dispepsia/fisiopatologia , Sistema Nervoso Entérico/fisiologia , Gastroenterite/fisiopatologia , Gastroenteropatias/tratamento farmacológico , Motilidade Gastrointestinal/efeitos dos fármacos , Motilidade Gastrointestinal/fisiologia , Humanos , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/metabolismo , Síndrome do Intestino Irritável/fisiopatologia , Neurônios/fisiologia , Percepção da Dor/fisiologia , Receptores de Serotonina/classificação , Receptores de Serotonina/efeitos dos fármacos , Receptores de Serotonina/fisiologia , Serotonina/metabolismo , Antagonistas da Serotonina/farmacologia , Antagonistas da Serotonina/uso terapêutico , Proteínas da Membrana Plasmática de Transporte de Serotonina/fisiologia , Agonistas do Receptor de Serotonina/farmacologia , Agonistas do Receptor de Serotonina/uso terapêutico , Nervo Vago/fisiologia , Dor Visceral/fisiopatologia
13.
Bone Marrow Transplant ; 45(6): 1052-5, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19855442

RESUMO

EBV-associated post transplant lymphoproliferative disease (EBV-PTLD) is a life-threatening complication that may occur after hemopoietic SCT. We prospectively screened 80 children on a weekly basis using nested quantitative PCR to evaluate EBV genome copies. EBV viral load <1000 copies per 10(5) PBMC was observed in 63% of transplants, whereas it was between 1000 and 9999 copies per 10(5) PBMC in 13%, and between 10 000 and 19 999 in 10%, with no significant increase in percentage of CD20+ lymphocytes. Viral load reached > or = 20 000 copies per 10(5) PBMC in 14% of patients, and rituximab was administered to 75% of them. None of the patients except one developed a lymphoproliferative disease. Our study found that only 13% of unrelated donor HSCT recipients had a very high risk of EBV-PTLD defined as > or = 20 000 geq per 10(5) PBMC associated with an increase in CD20+ lymphocyte. We suggest that rituximab could be administered in the presence of very high levels of EBV-DNA viral load or in the presence of mid levels of EBV-DNA viral load associated with an increase in the percentage of CD20+ lymphocytes. Through this approach, we significantly reduced the number of patients treated with rituximab, and consequently the acute and chronic adverse events related to this treatment.


Assuntos
Linfócitos B/patologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Herpesvirus Humano 4/fisiologia , Carga Viral , Ativação Viral , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Murinos , Antígenos CD20 , Criança , Pré-Escolar , DNA Viral/sangue , Feminino , Humanos , Contagem de Linfócitos , Transtornos Linfoproliferativos/etiologia , Transtornos Linfoproliferativos/prevenção & controle , Masculino , Estudos Prospectivos , Rituximab , Transplante Homólogo
14.
Neurogastroenterol Motil ; 21(11): 1209-e112, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19558426

RESUMO

In the central nervous system glial-derived S100B protein has been associated with inflammation via nitric oxide (NO) production. As the role of enteroglial cells in inflammatory bowel disease has been poorly investigated in humans, we evaluated the association of S100B and NO production in ulcerative colitis (UC). S100B mRNA and protein expression, inducible NO synthase (iNOS) expression, and NO production were evaluated in rectal biopsies from 30 controls and 35 UC patients. To verify the correlation between S100B and NO production, biopsies were exposed to S100B, in the presence or absence of specific receptor for advanced glycation end-products (RAGE) blocking antibody, to measure iNOS expression and nitrite production. S100B and iNOS expression were evaluated after incubation of biopsies with lipopolysaccharides (LPS) + interferon-gamma (IFN-gamma) in the presence of anti-RAGE or anti-S100B antibodies or budesonide. S100B mRNA and protein expression, iNOS expression and NO production were significantly higher in the rectal mucosa of patients compared to that of controls. Exogenous S100B induced a significant increase in both iNOS expression and NO production in controls and UC patients; this increase was inhibited by specific anti-RAGE blocking antibody. Incubation with LPS + IFN-gamma induced a significant increase in S100B mRNA and protein expression, together with increased iNOS expression and NO production. LPS + IFN-gamma-induced S100B up-regulation was not affected by budesonide, while iNOS expression and NO production were significantly inhibited by both specific anti-RAGE and anti-S100B blocking antibodies. Enteroglial-derived S100B up-regulation in UC participates in NO production, involving RAGE in a steroid insensitive pathway.


Assuntos
Colite Ulcerativa/metabolismo , Mucosa Intestinal , Fatores de Crescimento Neural/metabolismo , Neuroglia/metabolismo , Óxido Nítrico/metabolismo , Proteínas S100/metabolismo , Adulto , Idoso , Biópsia , Feminino , Humanos , Interferon gama/metabolismo , Mucosa Intestinal/citologia , Mucosa Intestinal/inervação , Mucosa Intestinal/metabolismo , Lipopolissacarídeos/metabolismo , Masculino , Pessoa de Meia-Idade , Fatores de Crescimento Neural/genética , Neuroglia/citologia , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , RNA Mensageiro/metabolismo , Receptor para Produtos Finais de Glicação Avançada , Receptores Imunológicos/metabolismo , Subunidade beta da Proteína Ligante de Cálcio S100 , Proteínas S100/genética , Técnicas de Cultura de Tecidos
15.
J Phys Condens Matter ; 21(25): 254201, 2009 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-21828425

RESUMO

We measured parallel upper critical magnetic fields in Nb/PdNi and Nb/CuNi bilayers and Nb/PdNi/Nb and Nb/CuNi/Nb trilayers. In the bilayers case the measurements reveal a dependence of the reduced two-dimensional-three-dimensional crossover temperature, t(cr) = T(cr)/T(c), on the different values of the superconductor (S)/ferromagnet (F) interface transparencies. In the case of the trilayers we observe that the reduced crossover temperature as a function of the ferromagnetic layer thickness, d(F), reaches a value equal to one only when the π-phase occurs in these systems. Also in this case the influence of the interface transparency on the observed results is discussed.

16.
J Phys Condens Matter ; 21(25): 254207, 2009 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-21828431

RESUMO

We study the vortex dynamics in the instability regime induced by high dissipative states well above the critical current in Nb superconducting strips. The magnetic field and temperature behavior of the critical vortex velocity corresponding to the observed dynamic instability is ascribed to intrinsic non-equilibrium phenomena. The Larkin-Ovchinnikov (LO) theory of electronic instability in high velocity vortex motion has been applied to interpret the temperature dependence of the critical vortex velocity. The magnetic field dependence of the vortex critical velocity shows new features in the low-field regime not predicted by LO.

17.
Bone Marrow Transplant ; 41 Suppl 2: S100-3, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18545229

RESUMO

Viral infections are a rare complication in autologous hemopoietic stem cell transplant (HSCT) recipients but represent a frequent cause of disease after allogeneic HSCT. In the last years, there has been an increase in the number of viral diseases observed in these patients. This fact may be at least partially due to an improvement in diagnostic facilities, but the increasing number of transplant procedures and the more severe immunosuppression may also have played an important role.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Hospedeiro Imunocomprometido , Condicionamento Pré-Transplante/efeitos adversos , Viroses/imunologia , Criança , Humanos , Transplante Autólogo , Transplante Homólogo , Viroses/etiologia
18.
Neurogastroenterol Motil ; 20(7): 780-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18373521

RESUMO

Sweetened carbonated beverages are widely consumed, which has fuelled several conflicting opinions about their effects on upper digestive tract functions. We aimed to evaluate the effect of sweetened carbonated drinks, consumed with a standard meal, on gastro-oesophageal reflux, gastric emptying and gallbladder contraction and postmeal sensations in healthy subjects. Thirteen healthy volunteers (seven women, six males; median age 22 years) were tested following the intake of 300 mL sweetened water containing increasing concentrations of carbon dioxide (seven subjects), and of 300 mL sweetened commercial flavoured drink with and without carbon dioxide (six subjects). Gastro-oesophageal reflux, gastric emptying and gallbladder contraction were studied by pH-impedance, octanoic acid breath test and ultrasound respectively. Gastro-oesophageal refluxes were significantly increased 1 h after meal with both water and commercial beverages; only sweetened water without carbon dioxide determined a persistently increasing number of refluxes 2 h postmeal. No differences were found for gastric emptying, gallbladder contraction or postmeal symptoms with any of the beverages tested. This study shows that 300 mL of sweetened carbonated beverage with different levels of carbonation or a commercial soft drink do not modify the physiology of the upper digestive tract.


Assuntos
Bebidas Gaseificadas , Edulcorantes/metabolismo , Trato Gastrointestinal Superior/fisiologia , Adulto , Testes Respiratórios , Feminino , Vesícula Biliar/fisiologia , Esvaziamento Gástrico/fisiologia , Refluxo Gastroesofágico , Humanos , Masculino , Período Pós-Prandial , Inquéritos e Questionários , Água
19.
Environ Health ; 2(1): 10, 2003 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-12952547

RESUMO

BACKGROUND: HMO databases offer an opportunity for community based epidemiologic studies of asthma incidence, etiology and treatment. The incidence of asthma in HMO populations and the utility of HMO data, including use of computerized algorithms and manual review of medical charts for determining etiologic factors has not been fully explored. METHODS: We identified adult-onset asthma, using computerized record searches in a New England HMO. Monthly, our software applied exclusion and inclusion criteria to identify an "at-risk" population and "potential cases". Electronic and paper medical records from the past year were then reviewed for each potential case. Persons with other respiratory diseases or insignificant treatment for asthma were excluded. Confirmed adult-onset asthma (AOA) cases were defined as those potential cases with either new-onset asthma or reactivated mild intermittent asthma that had been quiescent for at least one year. We validated the methods by reviewing charts of selected subjects rejected by the algorithm. RESULTS: The algorithm was 93 to 99.3% sensitive and 99.6% specific. Sixty-three percent (n = 469) of potential cases were confirmed as AOA. Two thirds of confirmed cases were women with an average age of 34.8 (SD 11.8), and 45% had no evidence of previous asthma diagnosis. The annualized monthly rate of AOA ranged from 4.1 to 11.4 per 1000 at-risk members. Physicians most commonly attribute asthma to infection (59%) and allergy (14%). New-onset cases were more likely attributed to infection, while reactivated cases were more associated with allergies. Medical charts included a discussion of work exposures in relation to asthma in only 32 (7%) cases. Twenty-three of these (72%) indicated there was an association between asthma and workplace exposures for an overall rate of work-related asthma of 4.9%. CONCLUSION: Computerized HMO records can be successfully used to identify AOA. Manual review of these records is important to confirm case status and is useful in evaluation of provider consideration of etiologies. We demonstrated that clinicians attribute most AOA to infection and tend to ignore the contribution of environmental and occupational exposures.


Assuntos
Asma/epidemiologia , Exposição Ambiental/efeitos adversos , Sistemas Pré-Pagos de Saúde/estatística & dados numéricos , Adulto , Idade de Início , Algoritmos , Estudos Transversais , Exposição Ambiental/análise , Feminino , Humanos , Infecções/epidemiologia , Infecções/etiologia , Estudos Longitudinais , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , New England/epidemiologia , Estudos Prospectivos , Inquéritos e Questionários , Estados Unidos/epidemiologia
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