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61.
Pussinen PJ Jauhiainen M Vilkuna-Rautiainen T Sundvall J Vesanen M Mattila K Palosuo T Alfthan G Asikainen S 《Journal of lipid research》2004,45(1):139-147
Periodontitis, a consequence of persistent bacterial infection and chronic inflammation, has been suggested to predict coronary heart disease (CHD). The aim of this study was to investigate the impact of periodontitis on HDL structure and antiatherogenic function in cholesterol efflux in vitro. HDL was isolated from 30 patients (age 43.6 +/- 6.1 years, mean +/- SD) with periodontitis before and after (3.2 +/- 1.4 months) periodontal treatment. The capacity of HDL for cholesterol efflux from macrophages (RAW 264.7), HDL composition, and key proteins of HDL metabolism were determined. After periodontal treatment, phospholipid transfer protein (PLTP) activity was 6.2% (P<0.05) lower, and serum HDL cholesterol concentration, PLTP mass, and cholesteryl ester transfer protein activity were 10.7% (P<0.001), 7.1% (P=0.078), and 19.4% (P<0.001) higher, respectively. The mean HDL2/HDL3 ratio increased from 2.16 +/- 0.87 to 3.56 +/- 0.48 (P<0.05). HDL total phospholipid mass and sphingomyelin-phosphatidylcholine ratio were 7.4% (P<0.05) and 36.8% (P<0.001) higher, respectively. The HDL-mediated cholesterol efflux tended to be higher after periodontal treatment; interestingly, this increase was significant (P<0.05) among patients whose C-reactive protein decreased (53.7% reduction, P=0.015) and who were positive by PCR for Actinobacillus actinomycetemcomitans. These results suggest that periodontitis causes similar, but milder, changes in HDL metabolism than those that occur during the acute-phase response and that periodontitis may diminish the antiatherogenic potency of HDL, thus increasing the risk for CHD. 相似文献
62.
Movements in muscles are generated by the myosins which interact with the actin filaments. In this paper we present an electric theory to describe how the chemical energy is first stored in electrostatic form in the myosin system and how it is then released and transformed into work. Due to the longitudinal polarized molecular structure with the negative phosphate group tail, the ATP molecule possesses a large electric dipole moment (p(0)), which makes it an ideal energy source for the electric dipole motor of the actomyosin system. The myosin head contains a large number of strongly restrained water molecules, which makes the ATP-driven electric dipole motor possible. The strongly restrained water molecules can store the chemical energy released by ATP binding and hydrolysis processes in the electric form due to their myosin structure fixed electric dipole moments (p(i)). The decrease in the electric energy is transformed into mechanical work by the rotational movement of the myosin head, which follows from the interaction of the dipoles p(i) with the potential field V(0) of ATP and with the potential field Psi of the actin. The electrical meaning of the hydrolysis reaction is to reduce the dipole moment p(0)-the remaining dipole moment of the adenosine diphosphate (ADP) is appropriately smaller to return the low negative value of the electric energy nearly back to its initial value, enabling the removal of ADP from the myosin head so that the cycling process can be repeated. We derive for the electric energy of the myosin system a general equation, which contains the potential field V(0) with the dipole moment p(0), the dipole moments p(i) and the potential field psi. Using the previously published experimental data for the electric dipole of ATP (p(0) congruent with 230 debye) and for the amount of strongly restrained water molecules (N congruent with 720) in the myosin subfragment (S1), we show that the Gibbs free energy changes of the ATP binding and hydrolysis reaction steps can be converted into the form of electric energy. The mechanical action between myosin and actin is investigated by the principle of virtual work. An electric torque always appears, i.e. a moment of electric forces between dipoles p(0) and p(i)(/M/ > or = 16 pN nm) that causes the myosin head to function like a scissors-shaped electric dipole motor. The theory as a whole is illustrated by several numerical examples and the results are compared with experimental results. 相似文献
63.
Cervera MF Heinämäki J Krogars K Jörgensen AC Karjalainen M Colarte AI Yliruusi J 《AAPS PharmSciTech》2004,5(1):109-114
The film-forming ability of chitosan and binary mixtures of chitosan and native amylose corn starch (Hylon VII) was evaluated
with free films prepared by a casting/solvent evaporation method. Unplasticized and plasticized free chitosan films in aqueous
acetic acid and respective films containing a mixture of chitosan and native amylose starch in acetic acid were prepared.
Glycerol, sorbitol, and i-erythritol were used as plasticizers. Solid-state and mechanical properties of the films were studied
by powder x-ray diffractometry (XPRD), differential scanning calorimetry (DSC), and a materials testing machine. The films
composed of a mixture of chitosan and native amylose starch in acetic acid were clear and colorless. A plasticizer concentration
of 20% wt/wt (of the polymer weight) ws sufficient to obtain flexible films with all samples tested. X-ray diffraction patterns
and DSC thermograms indicated an amorphous state of the films independent of the type of plasticizer used. In conclusion,
incorporation of native amylose com starch into chitosan films improves the consistency and the mechanical properties of the
films. 相似文献
64.
Drying is one of the standard unit operations in the pharmaceutical industry and it is important to become aware of the circumstances
that dominate during the process. The purpose of this study was to test microcapsulated thermochromic pigments as heat indicators
in a fluid bed drying process. The indicator powders were manually granulated with α-lactose monohydrate resulting in three
particle-size groups. Also, pellets were coated with the indicator powders. The granules and pellets were fluidized in fluid
bed dryer to observe the progress of the heat flow in the material and to study the heat indicator properties of the indicator
materials. A tristimulus colorimeter was used to measure CIELAB color values. Color indicator for heat detection can be utilized
to test if the heat-sensitive API would go through physical changes during the pharmaceutical drying process. Both the prepared
granules and pellets can be used as heat indicator in fluid bed drying process. The colored heat indicators give an opportunity
to learn new aspects of the process at real time and could be exploded, for example, for scaling-up studies. 相似文献
65.
Benjamin M. Kraemer Simon Hook Timo Huttula Pekka Kotilainen Catherine M. O’Reilly Anu Peltonen Pierre-Denis Plisnier Jouko Sarvala Rashid Tamatamah Yvonne Vadeboncoeur Bernhard Wehrli Peter B. McIntyre 《PloS one》2015,10(7)
Lake Tanganyika, the deepest and most voluminous lake in Africa, has warmed over the last century in response to climate change. Separate analyses of surface warming rates estimated from in situ instruments, satellites, and a paleolimnological temperature proxy (TEX86) disagree, leaving uncertainty about the thermal sensitivity of Lake Tanganyika to climate change. Here, we use a comprehensive database of in situ temperature data from the top 100 meters of the water column that span the lake’s seasonal range and lateral extent to demonstrate that long-term temperature trends in Lake Tanganyika depend strongly on depth, season, and latitude. The observed spatiotemporal variation in surface warming rates accounts for small differences between warming rate estimates from in situ instruments and satellite data. However, after accounting for spatiotemporal variation in temperature and warming rates, the TEX86 paleolimnological proxy yields lower surface temperatures (1.46 °C lower on average) and faster warming rates (by a factor of three) than in situ measurements. Based on the ecology of Thaumarchaeota (the microbes whose biomolecules are involved with generating the TEX86 proxy), we offer a reinterpretation of the TEX86 data from Lake Tanganyika as the temperature of the low-oxygen zone, rather than of the lake surface temperature as has been suggested previously. Our analyses provide a thorough accounting of spatiotemporal variation in warming rates, offering strong evidence that thermal and ecological shifts observed in this massive tropical lake over the last century are robust and in step with global climate change. 相似文献
66.
67.
Astrid Murumägi Daniela Ungureanu Mariliina Arjama Ralf Bützow Jouko Lohi Hannu Sariola Jukka Kanerva Minna Koskenvuo Olli Kallioniemi 《Translational oncology》2021,14(4):101027
Genetic rearrangements involving the anaplastic lymphoma kinase (ALK) gene create oncogenic drivers for several cancers, including malignant peritoneal mesothelioma (MPeM). Here, we report genomic and functional precision oncology profiling on a rare case of a 5-year old patient diagnosed with wide-spread and aggressive MPeM, driven by STRN-ALK rearrangement. We established genomically representative patient-derived cancer cells (PDCs) from the tumor sample and performed high-throughput drug sensitivity testing with 527 oncology compounds to identify potent inhibitors. As expected, the PDCs were overall sensitive to the ALK inhibitors, although the eight different inhibitors tested had variable efficacy. We also discovered other effective inhibitors, such as MEK/ERK inhibitors and those targeting pathways downstream of ALK as well as Bcl-xl inhibitors. In contrast, most cytotoxic drugs were not very effective. ALK inhibitors synergized with MEK and PI3K/mTOR inhibitors, highlighting potential combinatorial strategies to enhance drug efficacy and tackle drug resistance. Based on genomic data and associated functional validation, the patient was treated with the ALK inhibitor crizotinib in combination with conventional chemotherapy (cisplatin and gemcitabine). A complete disease remission was reached, lasting now for over 3 years. Our results illustrate a rare pediatric cancer case, and highlight the potential of functional precision oncology to discover pathogenetic drivers, validate dependency on driver signals, compare different inhibitors against each other and potentially enhance targeted treatments by drug combinations. Such real-time implementation of functional precision oncology could pave the way towards safer and more effective personalized cancer therapies for individual pediatric cancer patients with rare tumors. 相似文献
68.
In northern Fennoscandia, the spatial and temporal grazing practices of semi-domesticated reindeer (Rangifer tarandus tarandus) vary, which implies different grazing effects dependent on natural conditions as well as management regime (i.e., timing
and intensity of grazing). We compared density and biomass of main plant groups in semi-dry mountain birch forests exposed
to either long-term summer or winter grazing in three reindeer herding districts in the northernmost Finland. Percent plant
cover, height, and biomass of reindeer lichens (Cladonia spp.) and dwarf shrubs (Vaccinium uliginosum, Calluna vulgaris, and Betula nana) were lower on summer ranges compared with winter ranges. The biomass of other dwarf shrubs (Vaccinium myrtillus and V. vitis-idaea), and graminoids and herbs, and the % cover of non-vegetated bare soil and litter were, however, higher on summer ranges
than on winter ranges. Young mountain birch shoots (Betula pubescens ssp. czerepanovii) were less frequent on summer ranges than on winter ranges. The total leaf biomass under the browsing height of reindeer
(<1.5 m) was also lower on summer ranges compared with winter ranges. Especially in drier and nutrient poor mountain birch
forests, intensive summer grazing reduces the quantity of lichens and total plant biomass which affects the ecological state
and productivity of these forests and also reduces especially their winter grazing value for reindeer. Therefore, in addition
to regulating the maximum sustained numbers of reindeer, pasture rotation systems that effectively protect dry and nutrient
poor vegetation from summer grazing and trampling should be encouraged. 相似文献
69.
70.
Hull split date, shell seal, and navel orangeworm, Amyelois transitella (Walker) (Lepidoptera: Pyralidae), infestation data for 19 varieties of almonds, Prunus dulcis (Mill.) D.A. Webb, were analyzed to determine the relationship of shell seal and hull split date on A. transitella infestation. Data for all varieties were collected from three University of California regional almond variety trials from 2003 to 2005, with a total of 8,550 nuts evaluated. A significant negative relationship was found between percentage of shell seal and percentage of navel orangeworm infestation, with lower percentage of shell seal correlating to higher percentage of infestation. Similarly, hull split date was negatively correlated with percentage of infestation, with later splitting varieties trending toward lower percentage of infestation. Although there are outlying varieties, hull split and shell seal are indeed significant components in varietal differences in almond navel orangeworm infestation. Understanding such factors gives insight into both the predictive value of almond characteristics related to navel orangeworm damage as well as other potential indicators. 相似文献