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51.
Intra-peritoneal Injection of Polyclonal Anti-Interferon Alpha Antibodies Cross the Blood Brain Barrier and Neutralize Interferon Alpha 总被引:1,自引:0,他引:1
The central nervous system (CNS) is known to be an immunologically privileged organ in the body largely because the blood
brain barrier (BBB) prevents the flow of large molecules, proteins, and cells from crossing into the CNS from the periphery.
These restrictive properties of the BBB have made it difficult to treat CNS diseases. In this study, mice were infected intracranially
(i.c.) with Sindbis virus (SV) and then treated either i.c. or intraperitoneally (i.p.) with neutralizing antibodies against
interferon alpha (IFNα). SV infected control mice received i.p. saline. Antibodies against mouse IFNα were detected in the
brain tissue of mice that received i.p. and i.c. injections of the antibody. ELISA analysis showed that both i.c. and i.p.
antibody treated mice had significantly decreased levels of IFNα in the brain tissue. Also, mice that received IFNα neutralizing
antibodies showed decreased presence of protein kinase R (PKR) measured by immunohistochemical densitometry, indicating the
antibody successfully inhibited IFNα. The data shows that antibodies are capable of crossing the BBB and inhibiting IFNα,
indicating that it is possible to target molecules of interest in the CNS with peripheral antibody treatment. 相似文献
52.
Hamilton DR Sas R Tyberg JV 《American journal of physiology. Heart and circulatory physiology》2004,287(4):H1700-H1704
Physiologists and clinicians commonly refer to "pressure" as a measure of the constraining effects of the pericardium; however, "pericardial pressure" is really a local measurement of epicardial radial stress. During diastole, from the bottom of the y descent to the beginning of the a wave, pericardial pressure over the right atrium (P(pRA)) is approximately equal to that over the right ventricle (P(pRV)). However, in systole, during the interval between the bottom of the x descent and the peak of the v wave, these two pericardial pressures appear to be completely decoupled in that P(pRV) decreases, whereas P(pRA) remains constant or increases. This decoupling indicates considerable mechanical independence between the RA and RV during systole. That is, RV systolic emptying lowers P(pRV), but P(pRA) continues to increase, suggesting that the relation of the pericardium to the RA must allow effective constraint, even though the pericardium over the RV is simultaneously slack. In conclusion, we measured the pericardial pressure responsible for the previously reported nonuniformity of pericardial strain. P(pRA) and P(pRV) are closely coupled during diastole, but during systole they become decoupled. Systolic nonuniformity of pericardial constraint may augment the atrioventricular valve-opening pressure gradient in early diastole and, so, affect ventricular filling. 相似文献
53.
Junctions between lens fiber cells are labeled with a monoclonal antibody shown to be specific for MP26 总被引:9,自引:7,他引:2
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A monoclonal antibody (mcAb) that recognizes an intracellular domain of the major lens membrane protein in both chicken and bovine lenses is described. Mice were immunized with chicken lens fiber cell membranes that had been washed with 7 M urea. Hybridomas were screened by means of enzyme-linked immunosorbent assays and the molecular specificities of the mcAbs were determined using electrophoretic transfer procedures, "Westerns." One of these mcAbs, an IgG designated B2, reacted with a single band of 28,000 Mr from the chicken embryo lens (MP28) and the analogous 26,000 Mr protein in the bovine lens (MP26). Monoclonal B2 was shown to be specific for these proteins, since (a) heating in SDS caused MP26 to aggregate and reduced B2 binding to the protein band at an Mr of 26,000 in Western transfer analysis; (b) apparent dimers were bound by B2 in Western transfers; (c) soluble protein fractions from the lens contained no detectable B2 antigens; and (d) a cyanogen bromide fragment of MP26 was bound by B2. Studies with several proteases indicated that the antigenic site for B2 resides on a 2-kd, protease-sensitive region at the C-terminal end of MP26 and MP28. Evidence for B2 binding on the cytoplasmic side of the membrane comes from labeling studies done at the ultrastructural level. These studies, utilizing indirect methods with peroxidase and colloidal gold markers, clearly demonstrated that B2 labels two types of junctional profiles. In our calf lens membrane preparations after tannic acid staining, the predominant type (80%) measured 16-18 nn thick, with the second type measuring only 12-14 nm. Chick embryo lens cells that had differentiated in vitro and formed groups of lens fiber-like cells (termed lentoids), fluoresced brightly only when they had been permeabilized before labeling with B2 and a fluorochrome-conjugated antibody. This binding was concentrated at the plasma membranes of cells within the lentoids, even outside areas of cell-cell contact. Surrounding epithelioid cells were not stained. Solubilized lens cultures, examined by Westerns, displayed a single immunoreactive band, which co-migrated with MP28. 相似文献
54.
A study has been made of the effects of chloroform inhalation, Escherichia coli endotoxin injection and hydrocortisone injection on the absorption of a single intragastric dose of 65Zn by the chick. Injection of hydrocortisone increased the absorption of the 65Zn by 30-55% in both Zn-deficient and Zn-supplemented chicks. The influence of chloroform and endotoxin was less consistent; the former treatment only increased 65Zn absorption and endotoxin was less consistent; the former treatment only increased 65Zn absorption in Zn-supplemented chicks fed ad libitum whereas endotoxin only increased that in Zn-supplemented chicks on a restricted food intake. Injection of endotoxin increased the hepatic uptake of the absorbed 65Zn in both Zn-deficient and Zn-supplemented chicks, whereas hydrocortisone had a similar effect in the Zn-supplemented birds only. Chloroform inhalation increased hepatic 65Zn uptake in Zn-deficient chicks only. The increase in hepatic Zn concentrations in the stressed chicks was mainly associated with a protein in the cytosol identified as metallothionein. Both endotoxin and hydrocortisone decreased total plasma Zn concentrations in Zn-supplemented and Zn-deficient chicks; chloroform decreased plasma 65Zn content only. 相似文献
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58.
Ansgar Schulz Yahya Barry Franziska Stoek Aliou Ba Jana Schulz Mohamed L. Haki Miriam A. Sas Baba A. Doumbia Peter Kirkland Mohamed Y. Bah Martin Eiden Martin H. Groschup 《PLoS neglected tropical diseases》2021,15(4)
Crimean-Congo hemorrhagic fever virus (CCHFV) is one of the most widespread zoonotic arthropod-borne viruses in many parts of Africa, Europe and Asia. It belongs to the family of Nairoviridae in the genus of Orthonairovirus. The main reservoir and vector are ticks of the genus Hyalomma. Livestock animals (such as cattle, small ruminants and camels) develop a viremias lasting up to two weeks with absence of clinical symptoms, followed by seroconversion. This study was carried out to assess risk factors that affect seroprevalence rates in different species. In total, 928 livestock animal samples (cattle = 201; sheep = 247; goats = 233; camels = 247) from 11 out of 13 regions in Mauritania were assayed for CCHFV-specific immunoglobulin G (IgG) antibodies using enzyme-linked immunosorbent assays (ELISA) (including a novel indirect camel-IgG-specific CCHFV ELISA). Inconclusive results were resolved by an immunofluorescence assay (IFA). A generalized linear mixed-effects model (GLMM) was used to draw conclusions about the impact of certain factors (age, species, sex and region) which might have influenced the CCHFV antibody status of surveyed animals. In goats and sheep, about 15% of the animals were seropositive, whereas in cattle (69%) and camels (81%), the prevalence rate was significantly higher. On average, cattle and camels were up to twice to four times older than small ruminants. Interestingly, the seroprevalence in all species was directly linked to the age of the animals, i.e. older animals had significantly higher seroprevalence rates than younger animals. The highest CCHFV seroprevalence in Mauritania was found in camels and cattle, followed by small ruminants. The large proportion of positive animals in cattle and camels might be explained by the high ages of the animals. Future CCHFV prevalence studies should at least consider the age of surveyed animals in order to avoid misinterpretations. 相似文献
59.
Genetic diversity and distribution patterns of diploid and polyploid hybrid water frog populations (Pelophylax esculentus complex) across Europe
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Alexandra Hoffmann Jörg Plötner Nicolas B. M. Pruvost Ditte G. Christiansen Sandra Röthlisberger Lukáš Choleva Peter Mikulíček Dan Cogălniceanu István Sas‐Kovács Dmitry Shabanov Svyatoslav Morozov‐Leonov Heinz‐Ulrich Reyer 《Molecular ecology》2015,24(17):4371-4391
Polyploidization is a rare yet sometimes successful way for animals to rapidly create geno‐ and phenotypes that may colonize new habitats and quickly adapt to environmental changes. In this study, we use water frogs of the Pelophylax esculentus complex, comprising two species (Pelophylax lessonae, genotype LL; Pelophylax ridibundus, RR) and various diploid (LR) and triploid (LLR, LRR) hybrid forms, summarized as P. esculentus, as a model for studying recent hybridization and polyploidization in the context of speciation. Specifically, we compared the geographic distribution and genetic diversity of diploid and triploid hybrids across Europe to understand their origin, maintenance and potential role in hybrid speciation. We found that different hybrid and parental genotypes are not evenly distributed across Europe. Rather, their genetic diversity is structured by latitude and longitude and the presence/absence of parental species but not of triploids. Highest genetic diversity was observed in central and eastern Europe, the lowest in the northwestern parts of Europe. This gradient can be explained by the decrease in genetic diversity during postglacial expansion from southeastern glacial refuge areas. Genealogical relationships calculated on the basis of microsatellite data clearly indicate that hybrids are of multiple origin and include a huge variety of parental genomes. Water frogs in mixed‐ploidy populations without any parental species (i.e. all‐hybrid populations) can be viewed as evolutionary units that may be on their way towards hybrid speciation. Maintenance of such all‐hybrid populations requires a continuous exchange of genomes between diploids and triploids, but scenarios for alternative evolutionary trajectories are discussed. 相似文献
60.
Sas KM Janech MG Favre E Arthur JM Bell PD 《American journal of physiology. Renal physiology》2011,300(5):F1163-F1170
Renal epithelial cell primary cilia act as mechanosensors in response to changes in luminal fluid flow. To determine the role of cilia bending in the mechanosensory function of cilia, we performed proteomic analysis of collecting duct cell lines with or without cilia that were kept stationary or rotated to stimulate cilia bending. Expression of the Raf-1 kinase inhibitor protein (RKIP), an inhibitor of the MAPK pathway, was significantly elevated in rotated cilia (+) cells. This was compared with RKIP levels in cilia (-) cells that were stationary or rotated as well as in cilia (+) cells that were stationary. This result was confirmed in cilia knockout adult mice that had lower renal RKIP levels compared with adult mice with cilia. Downstream of RKIP, expression of phosphorylated ERK was decreased only in cells that had cilia and were subjected to constant cilia bending. Furthermore, elevated RKIP levels were associated with reduced cell proliferation. Blockade of PKC abrogated ciliary bending-induced increases in RKIP. In summary, we found that ciliary movement may help control the expression of the Raf-1 kinase inhibitor protein and thus maintain cell differentiation. In terms of polycystic kidney disease, loss of cilia and therefore sensitivity to flow may lead to reduced RKIP levels, activation of the MAPK pathway, and contribute to the formation of cysts. 相似文献