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1.
Reinnervation of experimental superficial wounds in rats 总被引:1,自引:0,他引:1
Sensory reinnervation of a superficial skin wound in the rat was studied by labeling sensory axons with anterogradely transported wheat germ agglutinin-horseradish peroxidase. Reinnervation starts after 3 days from the edge of the wound as well as from beneath the wound. About 2 weeks after the production of the wound, some hyperinnervation appears to be present, but after a few additional weeks, the innervation pattern is essentially normal. The results indicate that structural recovery of sensory axons is rapid and probably complete when skin wounds heal with no or minimal scar formation. 相似文献
2.
Nicolas Delaleu Heike Immervoll Janet Cornelius Roland Jonsson 《Arthritis research & therapy》2008,10(1):R22
Introduction
Sj?gren's syndrome (SS) is a systemic autoimmune disease that mainly targets the exocrine glands. The aim of this study was to investigate the involvement of 87 proteins measured in serum and 75 proteins analyzed in saliva in spontaneous experimental SS. In addition, we intended to compute a model of the immunological situation representing the overt disease stage of SS. 相似文献3.
Anna Nilsson Thomas E. Fehniger Lena Gustavsson Malin Andersson Kerstin Kenne Gy?rgy Marko-Varga Per E. Andrén 《PloS one》2010,5(7)
Readouts that define the physiological distributions of drugs in tissues are an unmet challenge and at best imprecise, but are needed in order to understand both the pharmacokinetic and pharmacodynamic properties associated with efficacy. Here we demonstrate that it is feasible to follow the in vivo transport of unlabeled drugs within specific organ and tissue compartments on a platform that applies MALDI imaging mass spectrometry to tissue sections characterized with high definition histology. We have tracked and quantified the distribution of an inhaled reference compound, tiotropium, within the lungs of dosed rats, using systematic point by point MS and MS/MS sampling at 200 µm intervals. By comparing drug ion distribution patterns in adjacent tissue sections, we observed that within 15 min following exposure, tiotropium parent MS ions (mass-to-charge; m/z 392.1) and fragmented daughter MS/MS ions (m/z 170.1 and 152.1) were dispersed in a concentration gradient (80 fmol-5 pmol) away from the central airways into the lung parenchyma and pleura. These drug levels agreed well with amounts detected in lung compartments by chemical extraction. Moreover, the simultaneous global definition of molecular ion signatures localized within 2-D tissue space provides accurate assignment of ion identities within histological landmarks, providing context to dynamic biological processes occurring at sites of drug presence. Our results highlight an important emerging technology allowing specific high resolution identification of unlabeled drugs at sites of in vivo uptake and retention. 相似文献
4.
H Carlsten N Nilsson R Jonsson K B?ckman R Holmdahl A Tarkowski 《Cellular immunology》1992,144(1):190-202
Estrogen is known to influence immune responses in healthy subjects in a dichotomous fashion. Thus, in number of previous studies we and others have demonstrated that B cell activities are augmented after exposure to estrogen whereas T cell reactivity is suppressed. Furthermore, it has been shown that this hormone has significant impact on the course of certain human and experimental autoimmune diseases. In this study we report that treatment with physiological doses of estradiol exerts dichotomous effects on different manifestations of the lupus disease in MRL/l mice. On one hand immune complex-mediated glomerulonephritis was significantly accelerated. This outcome was due to polyclonal B cell activation with increased production of antibodies to double-stranded DNA and formation of circulating immune complexes. In contrast, T cell-mediated lesions such as focal sialadenitis, renal vasculitis, and periarticular inflammation were all significantly ameliorated in MRL/l mice exposed to estrogen. Thus, we were able to demonstrate that, within one subject and even within one organ, administration of estrogen leads to differential outcome of SLE morbidity. We propose that the differential effect of estrogen on the manifestations of the autoimmune disease of MRL/l mice is due to its dichotomous effects on B and T cell-mediated immune responses. 相似文献
5.
6.
Summary Phenylalanine production from E. coli KA 197/pJN6 (plasmid harboring genes for aro F, phe AFBR, AmpR and TcR) was studied under varying nutritional conditions in batch and continuous cultures. In batch culture experiments where growth was deliberately interrupted by limiting concentrations of sulphate and phosphate the phenylalanine production continued from the non-growing cells. However, the depletion of phosphate resulted in an immediate cessation of phenylalanine production but thereafter a low specific rate of phenylalanine formation resumed, while the decrease in specific rate of product formation was less after sulphate depletion. In the chemostat experiments, however, phosphate limitation was the only case where the specific rate of phenylalanine formation remained constant, while at the corresponding time in sulphate and glucose limited chemostats it was declining respectively had ceased. 相似文献
7.
Lena Kautsky 《Ecography》1990,13(2):143-148
Sediment samples from 5 stations in the northern Baltic proper, 6.5 o/oo S, were collected in April 1987 and the emergence of seedlings was recorded over 120 days in a greenhouse at 20°C. Total seedling densities varied from 0 to 3328 m-2 : and of seven species, Zannichellia palustris and Chara spp. were the most abundant among seedlings and sporelings, respectively. Several common macrophytes in the area were rare as seedlings and no seedlings were recorded for the most abundant angiosperms, Potamogeton pectinatus, Potamogeton perfoliatus and Ranunculus baudotii. Except for the few annual species, reproduction by seeds contributed little to the dynamics of the vegetation in the area and no correlation was found between vegetation composition and the seed bank. For perennial species the winter survival of vegetative propagules is the most important factor for vegetation dynamics. 相似文献
8.
Summary Resource utilization by cutthroat trout (CT) and Dolly Varden charr (DV) was studied 8 years after experimental transfers from sympatry had established reproducing allopatric populations in two nearby fishless lakes. Allopatric DV significantly increased their utilization of shallow-dwelling zoobenthos, and increased their vertical distribution in comparison to that in sympatry. In contrast, allopatric CT showed little change in the proportions of major prey types utilized, and, if anything, restricted their vertical distribution in comparison to that in sympatry. The results can be explained by the hypothesis that the resource use of DV is strongly influenced by interspecific competition from CT, whereas CT largely remains unaffected by this interaction. An alternative hypothesis, that lake differences can explain the differences in resource use between sympatry and allopatry, was evaluated by comparing food resource availability and other biotic and abiotic characteristics of the three study lakes. None of these could account for the shift in resource use by DV between sympatry and allopatry, but lake differences may explain why allopatric CT showed a restricted habitat use in comparison with their sympatric donor stock. The results of this whole-lake transfer experiment are consistent with earlier reported field and laboratory studies, and suggest that the aggressive dominance of CT is the most important mechanism by which DV are displaced from littoral and near-surface habitats in sympathy with CT. 相似文献
9.
Lena Lewin Mats-Olof Mattsson David K. Rassin Åke Sellström 《Neurochemical research》1992,17(4):333-337
The uptake of radioactive -aminobutyric acid (GABA) andd-aspartate and the effect of SKF 89976-A, a non-substrate inhibitor of the GABA transporter, on this uptake have been investigated. Neuronal cultures from eight-day-old chick embryos grown for three or six days in vitro, were used as a model. For comparison, we also used the P2-fraction from rat. Neuronal cultures grown for three and six days expressed high-affinity uptake systems for [3H]GABA and ford-[3H]aspartate with an increasing Vmax during this period. The lipophilic non-substrate GABA uptake inhibitor, SKF 89976-A, inhibited transporter mediated uptake of GABA both in cell cultures from chicken, and in P2-fractions from rat. The results also showed that SKF 89976-A was a poor inhibitor of the uptake ofd-aspartate. We found no non-saturable uptake ofd-aspartate. 相似文献
10.
Summary
Pleurotus florida was grown in submerged culture with different concentrations of sugar beet pulp with a view to its nutritional upgrading.
Micelial growth, protein enrichment and dry weight loss of the solid residues of cultures, as well as the evolution of reducing
sugars in the liquid medium, were followed for 14 days. A product with 45% (w/w) protein and a saccharification extent as
high as 35% (w/w) were obtained after 7 days with 1% (w/v) sugar beet pulp. 相似文献