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991.
992.
Lipid metabolism-related gene mutations can cause retinitis pigmentosa, a currently untreatable blinding disease resulting from progressive neurodegeneration of the retina. Here, we demonstrated the influence of adiponectin receptor 1 (ADIPOR1) deficiency in retinal neurodegeneration using Adipor1 knockout (KO) mice. Adipor1 mRNA was observed to be expressed in photoreceptors, predominately within the photoreceptor inner segment (PIS), and increased after birth during the development of the photoreceptor outer segments (POSs) where photons are received by the visual pigment, rhodopsin. At 3 weeks of age, visual function impairment, specifically photoreceptor dysfunction, as recorded by electroretinography (ERG), was evident in homozygous, but not heterozygous, Adipor1 KO mice. However, although photoreceptor loss was evident at 3 weeks of age and progressed until 10 weeks, the level of visual dysfunction was already substantial by 3 weeks, after which it was retained until 10 weeks of age. The rhodopsin mRNA levels had already decreased at 3 weeks, suggesting that reduced rhodopsin may have contributed to early visual loss. Moreover, inflammation and oxidative stress were induced in homozygous KO retinas. Prior to observation of photoreceptor loss via optical microscopy, electron microscopy revealed that POSs were present; however, they were misaligned and their lipid composition, including docosahexaenoic acid (DHA), which is critical in forming POSs, was impaired in the retina. Importantly, the expression of Elovl2, an elongase of very long chain fatty acids expressed in the PIS, was significantly reduced, and lipogenic genes, which are induced under conditions of reduced endogenous DHA synthesis, were increased in homozygous KO mice. The causal relationship between ADIPOR1 deficiency and Elovl2 repression, together with upregulation of lipogenic genes, was confirmed in vitro. Therefore, ADIPOR1 in the retina appears to be indispensable for ELOVL2 induction, which is likely required to supply sufficient DHA for appropriate photoreceptor function and survival.Subject terms: Mechanisms of disease, Developmental neurogenesis  相似文献   
993.
994.
Guinea pig MIF (MIF/MAF), which was purified by immunoadsorbent column chromatography using an antibody against MIF/MAF, was observed to induce characteristic cell surface changes in macrophages under scanning electron microscopy (SEM). MIF/MAF induced enlarged petal-like ruffles in both rounded and spreading macrophages. The changes were observed as early as 2 hr after stimulation with MIF/MAF and continued for 24 hr. These morphological changes appeared to be a good indicator of macrophage activation and migration inhibition in the early phase. The mechanism of the characteristic ruffle formation was studied using metabolic inhibitors and reagents known to affect microfilaments and microtubules. When macrophages were treated with MIF/MAF in the presence of mitomycin C, actinomycin D, or puromycin, formation of the petal-like ruffles was not affected. However, vinblastine and cytochalasin B inhibited the induction of these ruffles. These results indicate that microtubule and microfilament assembly, but not synthesis of DNA, RNA, and protein, are required for the formation of the petal-like ruffles. In addition, treatment with a Ca2+ ionophore induced the same petal-like ruffles in macrophages, while treatment with dibutyryl-cyclic AMP or-cyclic GMP did not. These findings suggest that Ca2+ plays an important role in macrophage activation by MIF/MAF, especially in the early phase.  相似文献   
995.
Mitogenicity and the polyclonal plaque forming cell(PFC)-inducing property of a water soluble-adjuvant extracted from Bacterionema matruchotii by butanol (Bu-WSA) were examined in vitro in the spleen cells of hybrid (CBA/N female × BALB/c male) F1 mice and C3H strain of mice. The hybrid F1 male cells which expressed a CBA/N-defect were unable to respond to Bu-WSA, when assessed by the incorporation of [3H] thymidine into the cells and the generation of anti-trinitrophenyl (TNP)-PFC or autoantibody PFC defined by the anti-bromel-ain-treated mouse erythrocyte PFC assay. However, hybrid F1 female cells with normal traits responded to Bu-WSA. Cultured spleen cells of bacterial lipopolysaccharide (LPS)-nonresponsive C3H/HeJ mice responded to Bu-WSA as in the case of cells of LPS-responsive C3H/He mice, and the [3H]thymidine-uptakes and the numbers of PFC in these culture cells increased. Re-extraction of Bu-WSA by phenol did not affect its activities, while the activity of butanol-extracted LPS on C3H/HeJ cells decreased after re-extraction by the same procedure with phenol.  相似文献   
996.
Pulsatile flows in glass models simulating fusiform and lateral saccular aneurysms were investigated by a flow visualization method. When resting fluid starts to flow, the initial fluid motion is practically irrotational. After a short period of time, the flow began to separate from the proximal wall of the aneurysm. Then the separation bubble or vortex grew rapidly in size and filled the whole area of the aneurysm circumferentially. During this period of time, the center of the vortex moved from the proximal end to the distal point of the aneurysm. The transient reversal flow, for instance, which may occur at the end of the ejection period, passed between the wall of the aneurysm and the centrally located vortex. When the rate and pulsatile frequency of flow were high, the vortex broke down into highly disturbed flow (or turbulence) at the distal portion of the aneurysm. The same effect was observed when the length of the aneurysm was increased. A reduction in pulsatile amplitude made the flow pattern close to that in steady flow. A finite element analysis was made to obtain velocity and pressure fields in pulsatile flow through a tube with an axisymmetric expansion. Calculations were performed with the pulsatile flows used in the visualization experiment in order to study the effects of change in the pulsatile wave form by keeping the time-mean Reynolds number and Womersley's parameter unchanged. Calculated instantaneous patterns of velocity field and stream lines agreed well with the experimental results. The appearance and disappearance of the vortex in the dilated portion and its development resulted in complex distributions of pressure and shear fields. Locally minimum and maximum values of wall shear stress occurred at points just upstream and downstream of the distal end of the expansion when the flow rate reached its peak.  相似文献   
997.
998.
We established 11 hybridomas producing monoclonal antibodies (MoAbs), designated AM, against human myeloperoxidase (MPO), by immunizing mice with the three forms of MPO (I, II, and III) purified from healthy human polymorphonuclear leukocytes (PMN) and characterized the specificity of the AM MoAbs. Ten of the AM MoAbs reacted similarly to each of the three forms using an enzyme-linked immunosorbent assay. When a cetyltrimethylammonium bromide (CETAB) extract of human PMN was electrophoresed in a CETAB polyacrylamide gel and transferred to a nitrocellulose filter, IgG1 class AM MoAbs immunostained only the MPO band of the proteins of the extract. In addition, the AM MoAbs reacted to two radioactive bands of 94 and 92 kDa in a HL-60 cell lysate labeled with [35S]methionine for 1 h. After a chase period of 24 h, these bands were replaced by four radioactive bands of 64.5, 43, 16.7, and 13.4 kDa, demonstrating that the MoAbs recognize not only mature MPO but also the MPO precursors of 94 and 92 kDa. The data also indicated that the two major bands of 64.5 and 13.4 kDa corresponded to heavy and light chains of mature MPO, respectively, and the additive intermediate bands of 43 and 16.7 kDa were MPO-related proteins. Moreover, AM MoAbs reacted to a similar extent to the deglycosylated form of MPO III with endo-beta-N-acetylglucosaminidase H (Endo-H). Thus, IgG1 class AM MoAbs recognized MPO with high specificity and reacted to the structure which is commonly conserved in the three mature forms of MPO (I, II, and III), MPO precursors, and deglycosylated MPO with Endo-H. AM MoAbs also specifically reacted to PMN and/or monocytes but did not react to lymphocytes when the cell staining method was used.  相似文献   
999.
Isolation of an antigenically unique methanogen from human feces.   总被引:1,自引:1,他引:0       下载免费PDF全文
A methanogenic bacterium with the morphological and physiological properties of the genus Methanobrevibacter was isolated from the feces of a Japanese man who excreted methane in his breath. Indirect immunofluorescence staining revealed that the isolate had an antigenicity unrelated to that of any known members of the genus Methanobrevibacter.  相似文献   
1000.
Twenty-two isolates ofVerticillium dahliae, which were isolated from green soybeean (Glycine max), udo (Aralia cordata), horseradish (Cochlearia armoracia), sweetpea (Lathyrus odoratus), or a weed (Chenopodium album) were used in this study. Conidia and microsclerotia of these isolates were morphologically identical with those ofV. dahliae but did not coincide withV. longisporum. Pathogenicity tests showed that these isolates were of weak pathotype. Eleven of the 22 isolates, which were obtained from green soybean and udo, were pathogenic to green soybeans. Thus pathotype E was composed of two groups: ‘soybean pathotype’ which was pathogenic to green soybeans; and isolates nonpathogenic to green soybeans. The latter were defined as isolates of pathotype E in the narrow sense. Selected representativenit1 and NitM mutants of eachV. dahliae isolate were paired with VCGJ testers. Fourteen isolates ofV. dahliae (So1, So22, So23, So27, So28, So39, So40, So41, U54, U68, U69, U90, U95, and U115) showed complementary reactions with subgroups J1 and J3 and were assigned to subgroup J3. Isolate U108 was assigned to subgroup J2. Isolate HR1 was not compatible with any testers of VCGJ. With this exception, isolates of pathotype E in the narrow sense and those of ‘soybean pathotype’ were thus assigned to known VCGJ subgroups and did not form a unique group corresponding to their pathotype. ‘Soybean pathotype’ could not be distinguished among isolates of pathotype E by vegetative compatibility.  相似文献   
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