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Multiple sclerosis, the most common cause of neurological disability in young population after trauma, represents a significant public health burden. Current challenges associated with management of multiple sclerosis (MS) patients stem from the lack of biomarkers that might enable stratification of the different clinical forms of MS and thus prompt treatment for those patients with progressive MS, for whom there is currently no therapy available. In the present work we analyzed a set of thirty different plasma cytokines, chemokines and growth factors present in circulation of 129 MS patients with different clinical forms (relapsing remitting, secondary progressive and primary progressive MS) and 53 healthy controls, across two independent cohorts. The set of plasma analytes was quantified with Luminex xMAP technology and their predictive power regarding clinical outcome was evaluated both individually using ROC curves and in combination using logistic regression analysis. Our results from two independent cohorts of MS patients demonstrate that the divergent clinical and histology-based MS forms are associated with distinct profiles of circulating plasma protein biomarkers, with distinct signatures being composed of chemokines and growth/angiogenic factors. With this work, we propose that an evaluation of a set of 4 circulating biomarkers (HGF, Eotaxin/CCL11, EGF and MIP-1β/CCL4) in MS patients might serve as an effective tool in the diagnosis and more personalized therapeutic targeting of MS patients.  相似文献   
124.
Many ectotherms effectively reduce their exposure to low or high environmental temperatures using behavioral thermoregulation. In terrestrial ectotherms, thermoregulatory strategies range from accurate thermoregulation to thermoconformity according to the costs and limits of thermoregulation, while in aquatic taxa the quantification of behavioral thermoregulation have received limited attention. We examined thermoregulation in two sympatric newt species, Ichthyosaura alpestris and Lissotriton vulgaris, exposed to elevated water temperatures under semi-natural conditions. According to a recent theory, we predicted that species for which elevated water temperatures pose a lower thermal quality habitat, would thermoregulate more effectively than species in thermally benign conditions. In the laboratory thermal gradient, L. vulgaris maintained higher body temperatures than I. alpestris. Semi-natural thermal conditions provided better thermal quality of habitat for L. vulgaris than for I. alpestris. Thermoregulatory indices indicated that I. alpestris actively thermoregulated its body temperature, whereas L. vulgaris remained passive to the thermal heterogeneity of aquatic environment. In the face of elevated water temperatures, sympatric newt species employed disparate thermoregulatory strategies according to the species-specific quality of the thermal habitat. Both strategies reduced newt exposure to suboptimal water temperatures with the same accuracy but with or without the costs of thermoregulation. The quantification of behavioral thermoregulation proves to be an important conceptual and methodological tool for thermal ecology studies not only in terrestrial but also in aquatic ectotherms.  相似文献   
125.
Focused Ultrasound (FUS) coupled with intravenous administration of microbubbles (MB) is a non-invasive technique that has been shown to reliably open (increase the permeability of) the blood-brain barrier (BBB) in multiple in vivo models including non-human primates (NHP). This procedure has shown promise for clinical and basic science applications, yet the safety and potential neurological effects of long term application in NHP requires further investigation under parameters shown to be efficacious in that species (500kHz, 200–400 kPa, 4–5μm MB, 2 minute sonication). In this study, we repeatedly opened the BBB in the caudate and putamen regions of the basal ganglia of 4 NHP using FUS with systemically-administered MB over 4–20 months. We assessed the safety of the FUS with MB procedure using MRI to detect edema or hemorrhaging in the brain. Contrast enhanced T1-weighted MRI sequences showed a 98% success rate for openings in the targeted regions. T2-weighted and SWI sequences indicated a lack edema in the majority of the cases. We investigated potential neurological effects of the FUS with MB procedure through quantitative cognitive testing of’ visual, cognitive, motivational, and motor function using a random dot motion task with reward magnitude bias presented on a touchpanel display. Reaction times during the task significantly increased on the day of the FUS with MB procedure. This increase returned to baseline within 4–5 days after the procedure. Visual motion discrimination thresholds were unaffected. Our results indicate FUS with MB can be a safe method for repeated opening of the BBB at the basal ganglia in NHP for up to 20 months without any long-term negative physiological or neurological effects with the parameters used.  相似文献   
126.
Halobacterial megaplasmids are negatively supercoiled   总被引:1,自引:0,他引:1  
Several covalently closed circular halobacterial megaplasmids (up to more than 500 kb) from different strains of Halolerax mediterranei, have been resolved by orthogonal-field alternating gel electro-phoresis (OFAGE). These molecules seem to be negatively supercoiled in vivo, as deduced from the effect of intercalating agents affecting their topology and, therefore, their electrophoretic mobility. It has also been demonstrated that the topolsomerase II Inhibitor novobiocin affects the native topological state of halobacterial megaplasmids impeding their migration in OFAGE under standard conditions for resolution of large supercoiled molecules.  相似文献   
127.
In the red howler monkey, Alouatta seniculus stramineus (2n = 47, 48, or 49), variations in diploid chromosome number are due to different numbers of microchromosomes. Males exhibit a Y;autosome translocation involving the short arm of an individual biarmed autosome. Consequently, the sex-chromosome constitution in the male is X1X2Y1Y2, with X1 representing the original X chromosome, X2 the biarmed autosome (No. 7), Y1 the Y;7p translocation product, and Y2 the acrocentric homolog of 7q. In the first meiotic division, a quadrivalent with a chain configuration can be observed in spermatocytes. Females have an X1X1X2X2 sex-chromosome constitution. Chromosome heteromorphisms were observed in pair 13, due to a pericentric inversion, and pair 19, due to the presence of constitutive heterochromatin. Microchromosomes, which varied in number between individuals, were also heterochromatic. NOR-staining was observed at two separate sites on a single chromosome pair (No. 10). A comparison of A.s. stramineus with A.s. macconnelli shows that these two subspecies have identical diploid chromosome numbers (47, 48, or 49), again due to a varying number of microchromosomes, and that they share a similar sex-chromosome constitution. Their karyotypes, however, are not identical, but can be derived from each other by a reciprocal translocation. Further comparisons with other A. seniculus subspecies reported in the literature indicate that this taxon is not karyologically uniform and that substantial chromosome shuffling has occurred between populations that have been considered to be subspecies by taxonomic criteria based on their morphometric attributes.  相似文献   
128.
METABOLIC CHANGES IN THE BRAINS OF MICE FROZEN IN LIQUID NITROGEN   总被引:1,自引:1,他引:0  
Abstract— Autolytic changes in the mouse brain, occurring during immersion of the animal in liquid nitrogen, were evaluated by measuring the tissue concentrations of glucose, lactate, pyruvate, α-oxoglutarate, phosphocreatine, creatine, ATP, ADP and AMP. The values thus obtained were compared with those obtained in paralysed mice under nitrous oxide anaesthesia, the brains of which were frozen in such a way that arterial blood pressure and oxygénation were upheld during the freezing. Immersion of unanaesthetized mice in liquid nitrogen gave rise to significant alterations in phosphocreatine, creatine, lactate, lactate/pyruvate ratio, ADP and AMP. A comparison with values obtained in paralysed and anaesthetized mice that were frozen by immersion in liquid nitrogen showed that the metabolic changes observed in the unanaesthetized animals could not be caused by an anaesthetic effect on the metabolic pattern. It is concluded that autolysis in the mouse brain occurs during immersion of the animal in a coolant, mainly because arterial hypoxia develops before the tissue is frozen. A comparison with previous results on rat cerebral cortex indicates that mice offer no advantage for studies of cerebral metabolites in unanaesthetized animals. In both species, accurate analyses of labile cerebral metabolites require that the brain is frozen in a way that prevents arterial hypoxia during the fixation of the tissue.  相似文献   
129.
The content of the diterpene Marrubiin was assessed by GC-FID in leaves of Marrubium vulgare plants along their ontogeny. Maximum accumulation occurred just before flowering time and in fully expanded leaves. After feeding the plants with radio labeled [3H]-geranyl geranyl diphosphate, up to 70% of the radioactivity was recovered in HPLC-Rt coincidental with authentic Marrubiin, which was also characterized by GC-EIMS, thus confirming that the biosynthesis of Marrubiin proceeds through the 1-deoxy-D-xylulose-5-phosphate pathway. The major accumulation of radioactivity occurred in glandular trichome cells, and the product remained stable throughout.  相似文献   
130.
Abstract. Objectives: The ADAMs (a disintegrin and metalloproteinase) enzymes compose a family of membrane‐bound proteins characterized by their multi‐domain structure and ADAM‐12 expression is elevated in human non‐small cell lung cancers. The aim of this study was to investigate the roles played by ADAM‐12 in critical steps of bronchial cell transformation during carcinogenesis. Materials and methods: To assess the role of ADAM‐12 in tumorigenicity, BEAS‐2B cells were transfected with a plasmid encoding human full‐length ADAM‐12 cDNA, and then the effects of ADAM‐12 overexpression on cell behaviour were explored. Treatment of clones with heparin‐binding epidermal growth factor (EGF)‐like growth factor (HB‐EGF) neutralizing antibodies as well as an EGFR inhibitor allowed the dissection of mechanisms regulating cell proliferation and apoptosis. Results: Overexpression of ADAM‐12 in BEAS‐2B cells promoted cell proliferation. ADAM‐12 overexpressing clones produced higher quantities of HB‐EGF in their culture medium which may rely on membrane‐bound HB‐EGF shedding by ADAM‐12. Targeting HB‐EGF activity with a neutralizing antibody abrogated enhanced cell proliferation in the ADAM‐12 overexpressing clones. In sharp contrast, targeting of amphiregulin, EGF or transforming growth factor‐α failed to influence cell proliferation; moreover, ADAM‐12 transfectants were resistant to etoposide‐induced apoptosis and the use of a neutralizing antibody against HB‐EGF activity restored rates of apoptosis to be similar to controls.Conclusions: ADAM‐12 contributes to enhancing HB‐EGF shedding from plasma membranes leading to increased cell proliferation and reduced apoptosis in this bronchial epithelial cell line.  相似文献   
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