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61.

Background

Internet-based self-management has shown to improve asthma control and asthma related quality of life, but the improvements were only marginally clinically relevant for the group as a whole. We hypothesized that self-management guided by weekly monitoring of asthma control tailors pharmacological therapy to individual needs and improves asthma control for patients with partly controlled or uncontrolled asthma.

Methods

In a 1-year randomised controlled trial involving 200 adults (18-50 years) with mild to moderate persistent asthma we evaluated the adherence with weekly monitoring and effect on asthma control and pharmacological treatment of a self-management algorithm based on the Asthma Control Questionnaire (ACQ). Participants were assigned either to the Internet group (n = 101) that monitored asthma control weekly with the ACQ on the Internet and adjusted treatment using a self-management algorithm supervised by an asthma nurse specialist or to the usual care group (UC) (n = 99). We analysed 3 subgroups: patients with well controlled (ACQ ≤ 0.75), partly controlled (0.75>ACQ ≤ 1.5) or uncontrolled (ACQ>1.5) asthma at baseline.

Results

Overall monitoring adherence was 67% (95% CI, 60% to 74%). Improvements in ACQ score after 12 months were -0.14 (p = 0.23), -0.52 (p < 0.001) and -0.82 (p < 0.001) in the Internet group compared to usual care for patients with well, partly and uncontrolled asthma at baseline, respectively. Daily inhaled corticosteroid dose significantly increased in the Internet group compared to usual care in the first 3 months in patients with uncontrolled asthma (+278 μg, p = 0.001), but not in patients with well or partly controlled asthma. After one year there were no differences in daily inhaled corticosteroid use or long-acting β2-agonists between the Internet group and usual care.

Conclusions

Weekly self-monitoring and subsequent treatment adjustment leads to improved asthma control in patients with partly and uncontrolled asthma at baseline and tailors asthma medication to individual patients'' needs.

Trial registration

Current Controlled Trials ISRCTN79864465  相似文献   
62.

Background  

The assembly and spatial organization of enzymes in naturally occurring multi-protein complexes is of paramount importance for the efficient degradation of complex polymers and biosynthesis of valuable products. The degradation of cellulose into fermentable sugars by Clostridium thermocellum is achieved by means of a multi-protein "cellulosome" complex. Assembled via dockerin-cohesin interactions, the cellulosome is associated with the cell surface during cellulose hydrolysis, forming ternary cellulose-enzyme-microbe complexes for enhanced activity and synergy. The assembly of recombinant cell surface displayed cellulosome-inspired complexes in surrogate microbes is highly desirable. The model organism Lactococcus lactis is of particular interest as it has been metabolically engineered to produce a variety of commodity chemicals including lactic acid and bioactive compounds, and can efficiently secrete an array of recombinant proteins and enzymes of varying sizes.  相似文献   
63.
As a contribution to the development of novel vanadyl complexes with potential insulin-mimetic activity, three new oxovanadium(IV) complexes with the formula VO(L)(2), where L are 3-amino-quinoxaline-2-carbonitrile N(1),N(4)-dioxide derivatives, have been synthesized. Complexes have been characterized by elemental and thermal analyses, fast atom bombardment mass spectroscopy (FAB-MS), conductivity measurements and electronic, Fourier transform infrared (FTIR) and electron paramagnetic resonance (EPR) spectroscopies. The in vitro insulin-mimetic activity of the vanadyl complexes has been estimated by lipolysis inhibition tests, in which the inhibition of the release of free fatty acid from isolated rat adipocytes treated with epinephrine was determined. All the complexes showed inhibitory effects on free fatty acid release. [V(IV)O(3-amino-6(7)-bromoquinoxaline-2-carbonitrile N(1),N(4)-dioxide)(2)] exhibited higher in vitro insulin-mimetic activity than the very active bis(6-methylpicolinato)oxovanadium(IV), VO(6mpa)(2). This new vanadyl complex is expected to exhibit a higher blood glucose lowering activity than VO(6mpa)(2) in diabetic animals.  相似文献   
64.
Developing and mature midbrain dopamine (DA) neurons express fibroblast growth factor (FGF) receptor-1 (FGFR1). To determine the role of FGFR1 signaling in the development of DA neurons, we generated transgenic mice expressing a dominant negative mutant [FGFR1(TK-)] from the catecholaminergic, neuron-specific tyrosine hydroxylase (TH) gene promoter. In homozygous th(tk-)/th(tk-) mice, significant reductions in the size of TH-immunoreactive neurons were found in the substantia nigra compacta (SNc) and the ventral tegmental area (VTA) at postnatal days 0 and 360. Newborn th(tk-)/th(tk-) mice had a reduced density of DA neurons in both SNc and VTA, and the changes in SNc were maintained into adulthood. The reduced density of DA transporter in the striatum further demonstrated an impaired development of the nigro-striatal DA system. Paradoxically, the th(tk-)/th(tk-) mice had increased levels of DA, homovanilic acid and 3-methoxytyramine in the striatum, indicative of excessive DA transmission. These structural and biochemical changes in DA neurons are similar to those reported in human patients with schizophrenia and, furthermore, these th(tk-)/th(tk-) mice displayed an impaired prepulse inhibition that was reversed by a DA receptor antagonist. Thus, this study establishes a new developmental model for a schizophrenia-like disorder in which the inhibition of FGF signaling leads to alterations in DA neurons and DA-mediated behavior.  相似文献   
65.
Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in Western countries and is considered the hepatic manifestation of metabolic syndrome. The hallmark of NAFLD is hepatic neutral lipid accumulation, mainly triacylglycerol, in the absence of significant ethanol consumption, viral infection or other specific etiologies. Hepatic lipid accumulation results from an imbalance between lipid availability (from circulating lipid uptake or de novo lipogenesis) and lipid disposal (via free fatty acid oxidation or triglyceride-rich lipoprotein secretion) and eventually triggers lipoperoxidative stress and hepatic injury. Each of these steps is altered in NAFLD, although to a different extent. Regulation of these pathways is complex and involves nuclear receptors, membrane transport proteins and cellular enzymes. We will review available data on different steps of hepatic lipid metabolism in NAFLD and recent advances in understanding molecular mechanisms underlying hepatic fat accumulation in these subjects.  相似文献   
66.

Background

The aim of this study was to analyse the nutraceutical properties of table green olives Nocellara del Belice, a traditional Mediterranean food. The Mediterranean Diet has as key elements olives and extra virgin olive oil, common to all Mediterranean countries. Olive oil is the main source of fat and can modulate oxidative stress and inflammation, whereas little is known about the role of olives. Moreover, emerging evidences underline the association between gut microbiota and food as the basis of many phenomena that affect health and delay or avoid the onset of some age-related chronic diseases.

Methods

In order to show if table green olives have nutraceutical properties and/or probiotic effect, we performed a nutritional intervention, administering to 25 healthy subjects (mean age 38,3), 12 table green olives/day for 30 days. We carried out anthropometric, biochemical, oxidative stress and cytokines analyses at the beginning of the study and at the end. Moreover, we also collected fecal samples to investigate about the possible variation of concentration of Lactobacilli, after the olives consumption.

Result

Our results showed a significant variation of one molecule related to oxidative stress, malondialdehyde, confirming that Nocellara del Belice green olives could have an anti-oxidant effect. In addition, the level of interleukin-6 decreased significantly, demonstrating how this food could be able to modulate the inflammatory response. Moreover, it is noteworthy the reduction of fat mass with an increase of muscle mass, suggesting a possible effect on long time assumption of table olives on body mass variation. No statistically significant differences were observed in the amount of Lactobacilli, although a trend towards an increased concentration of them at the end of the intervention could be related to the nutraceutical effects of olives.

Conclusion

These preliminary results suggest a possible nutraceutical effect of daily consumption of green table olives Nocellara del Belice. To best of our knowledge, this is the first study performed to assess nutraceutical properties of this food. Of course, it is necessary to verify the data in a larger sample of individuals to confirm their role as nutraceuticals.
  相似文献   
67.
The uptake of the nuclear waste product technetium-99 was studied in common duckweed (Lemna minor). In addition to measurements, a model involving two compartments in duckweed with different chemical forms of technetium was derived. The model was tested by chemical speciation, i.e. differentiating between reduced Tc-compounds and Tc(VII)O(4)(-). The TcO(4)(-) concentrations measured were in good agreement with those predicted by the model. Two processes determine technetium uptake: (1) transport of Tc(VII)O(4)(-) across the cell membrane, and (2) reduction of Tc(VII). The TcO(4)(-) concentration in duckweed reaches a steady state within 2 h while reduced Tc-compounds are stored, as a result of absence of release or re-oxidation processes. Bioaccumulation kinetic properties were derived by varying 99Tc concentration, temperature, nutrient concentrations, and light intensity. The reduction of technetium in duckweed was highly correlated with light intensity and temperature. At 25 degrees C the maximum reduction rate was observed at light intensities above 200 μmol m(-2) s(-1) while half of the maximum transformation rate was reached at 41 μmol m(-2) s(-1). Transport of TcO(4)(-) over the cell membrane requires about 9.4 kJ mol(-1), indicating an active transport mechanism. However, this mechanism behaved as first-order kinetics instead of Michaelis-Menten kinetics between 1x10(-14) and 2.5x10(-5) mol l(-1) TcO(4)(-). Tc uptake could not be inhibited by 10(-3) mol l(-1) nitrate, phosphate, sulphate or chloride.  相似文献   
68.
Palladium(II) complexes of 2-benzoylpyridine thiosemicarbazone (H2Bz4DH) and its N4-methyl (H2Bz4M) and N4-phenyl (H2Bz4Ph) derivatives were obtained and fully characterized. [Pd(2Bz4DH)Cl] (1) crystallizes in the monoclinic space group P21/c with a=11.671(1), b=10.405(1), c=13.124(1), beta=115.60(1) degrees and Z=4; [Pd(2Bz4M)Cl] (2) in the monoclinic space group P21/c with a=9.695(1), b=15.044(1), c=10.718(1) A, beta=105.38(1) degrees and Z=4 and [Pd(2Bz4Ph)Cl] (3) in the triclinic space group P1 with a=9.389(1), b=13.629(1), c=15.218(1) A, alpha=70.25(1), beta=73.46(1), gamma=83.57(1) degrees and two independent molecules per asymmetric unit (Z=4). All complexes show a quite similar planar fourfold environment around palladium(II). A negatively charged organic molecule acts as a tridentate ligand and binds to the metal through the pyridine nitrogen, the imine nitrogen and the sulfur atom. A chloride ion occupies the fourth coordination site. The planar complexes stack nearly parallel to one another in the lattice conforming a layered crystal structure. The cytotoxic activity of the thiosemicarbazones and their metal complexes was tested against the MCF-7, TK-10 and UACC-62 human tumor cell lines. The ligands exhibit lower values of GI50 and LC50 than the complexes, H2Bz4Ph being the most active with GI50<0.003 microM; LC50=13.4 microM; GI50=9.3 microM, LC50=12.9 microM; GI50<0.003, LC50=13.8 microM in the MCF-7, TK-10 and UACC-62 cell lines, respectively. Among the complexes, [Pd(2Bz4Ph)Cl] (3) exhibited the lowest values of GI50 in the three studied cell lines.  相似文献   
69.
As a contribution to the development of novel vanadium complexes with pharmacologically interesting moieties, new dioxovanadium(V) semicarbazone complexes with the formula cis-VO(2)L, where L=5-bromosalicylaldehyde semicarbazone and 2-hydroxynaphtalen-1-carboxaldehyde semicarbazone have been synthesized and characterized by (1)H and (13)C NMR, Raman and FTIR spectroscopies. Results were compared with those previously reported for other three analogous complexes of this series. The five complexes were tested in three different human tumor cell lines for bioactivity as potential anti-tumor agents, showing selective cytotoxicity on TK-10 cell line. Results showed that structural modifications on the semicarbazone moiety could have a significant effect on the anti-tumor activity of the vanadium complexes. In addition, the electrochemical behavior of all the complexes was studied. No apparent correlation could be demonstrated between reduction potentials of the complexes and their anti-tumor activities. The molecular structure of the novel [V(V)O(2)(5-bromosalicylaldehyde semicarbazone)] complex was solved by X-ray diffraction methods. The vanadium atom shows a distorted square pyramidal coordination sphere. The (VO(2))(+) cation is coordinated to a nearly planar (L)(-) anion acting as a tridentate ligand through both oxygen and one nitrogen atoms.  相似文献   
70.
The Grapevine FanLeaf Virus-Coat Protein (GFLV CP) gene was inserted through Agrobacterium-mediated transformation in Vitis vinifera ‘Nebbiolo’, ‘Lumassina’ and ‘Blaufränkisch’. Two plasmids were used: pGA-CP+ (full-length GFLV CP gene with an introduced start codon) and pGA-AS (same gene in antisense orientation). Forty-three transgenic lines were regenerated. As several lines in Southern blots share same hybridization patterns, eight independent line groups resulted for ‘Nebbiolo’, one for ‘Lumassina’, and two for ‘Blaufränkisch’. Inserted T-DNA copies ranged from one to three; one line probably contains an incomplete copy of T-DNA. Except for one ‘Nebbiolo’ line, no evidence for methylation of the transgene at cytosine residues was found by Southern analyses. Specific mRNA was present at variable expression levels; some lines accumulated the coat protein while in others the protein was not detectable by ELISA.  相似文献   
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