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61.
Polyclonal rabbit antibodies against a Ca2+-binding mitochondrial glycoprotein were found to inhibit the uniporter-mediated transport of Ca2+ in mitoplasts prepared from rat liver mitochondria. Spermine, a modulator of the uniporter, decreased the inhibition. This glycoprotein ofM r 40,000, isolated from beef heart mitochondria and earlier shown to form Ca2+-conducting channels in black-lipid membranes, thus is a good candidate for being a component of the uniporter. Antibody-IgG was found to specifically bind to mitochondria in human fibroblasts.  相似文献   
62.
Human myelin was isolated from the white matter of autopsy brains. Myelin proteins were characterized by isoelectric focusing in ultrathin slab gels in a pH range from 3.5 to 10 after solubilization with urea and Nonidet P 40. The protein profile in the acidic region (pH below 6.2) revealed at least twelve faint bands which comprised only a few percent of the total myelin proteins. Most of the myelin proteins were focused in the neutral range (pH 6.2–7.8) which showed two sharper and three broader major bands, the total number of bands in this region being about twenty. The basic pH range (pH above 7.8) contained about 30% of the proteins, and revealed a very intense band near the cathode with seven to nine weaker bands below pH 9.0. When the myelin was partially delipidated prior to solubilization, an additional broad band was observed at the area pH 8.0–8.5.  相似文献   
63.
Abstract Laminin, the major glycoprotein of basement membranes, was shown to be bound by the human gastric pathogen Helicobacter pylori . Binding of 125I-laminin by strain 17874 was time-dependent, specific and saturable. Scatchard analysis of specific binding indicated about 2000 binding sites per cell with a dissociation constant of 8.5 pM. Treatment of the cells by heat (80°) and with proteolytic enzymes drastically reduced laminin binding, suggesting that the laminin receptors are surface proteins. Some highly glycosylated glycoproteins inhibited laminin binding by 50%. Furthermore, N -acetylneuraminyllactose decreased laminin binding by 70% and neuraminidase treatment of laminin by 50%, while a recombinant B1 chain of laminin, containing high-mannose type oligosaccharides, inhibited binding by only 25%. This suggests that terminal sialic acids on laminin compete for a specific sugar binding protein(s) on H. pylori cells.  相似文献   
64.
Kaija H. Valkonen 《Life sciences》1980,27(13):1217-1224
The liver histones of calf embryos, calves and adult cows were analyzed by use of a high-resolution sodium dodecyl sulfate slab gel electrophoresis. The results show both qualitative and quantitative changes in the Hl histones. The Hl histone of the young embryos appeared as two components, that of the embryo at seven months of age as three components and that of the older embryos, as also that of the calves and adult cows, as four components. In addition, the relative proportion of the Hl histones increased during the whole ontogeny.  相似文献   
65.
66.

Introduction

Evidence suggests that citrullinated fibrin(ogen) may be a potential in vivo target of anticitrullinated protein/peptide antibodies (ACPA) in rheumatoid arthritis (RA). We compared the diagnostic yield of three enzyme-linked immunosorbent assay (ELISA) tests by using chimeric fibrin/filaggrin citrullinated synthetic peptides (CFFCP1, CFFCP2, CFFCP3) with a commercial CCP2-based test in RA and analyzed their prognostic values in early RA.

Methods

Samples from 307 blood donors and patients with RA (322), psoriatic arthritis (133), systemic lupus erythematosus (119), and hepatitis C infection (84) were assayed by using CFFCP- and CCP2-based tests. Autoantibodies also were analyzed at baseline and during a 2-year follow-up in 98 early RA patients to determine their prognostic value.

Results

With cutoffs giving 98% specificity for RA versus blood donors, the sensitivity was 72.1% for CFFCP1, 78.0% for CFFCP2, 71.4% for CFFCP3, and 73.9% for CCP2, with positive predictive values greater than 97% in all cases. CFFCP sensitivity in RA increased to 80.4% without losing specificity when positivity was considered as any positive anti-CFFCP status. Specificity of the three CFFCP tests versus other rheumatic populations was high (> 90%) and similar to those for the CCP2. In early RA, CFFCP1 best identified patients with a poor radiographic outcome. Radiographic progression was faster in the small subgroup of CCP2-negative and CFFCP1-positive patients than in those negative for both autoantibodies. CFFCP antibodies decreased after 1 year, but without any correlation with changes in disease activity.

Conclusions

CFFCP-based assays are highly sensitive and specific for RA. Early RA patients with anti-CFFCP1 antibodies, including CCP2-negative patients, show greater radiographic progression.  相似文献   
67.
An extra layer of complexity in the regulation of gene expression in bacteria is now apparent through previously unanticipated roles of noncoding and antisense RNAs.  相似文献   
68.
69.

Background

Immunoglobulin A (IgA) secretion in saliva decreases with age and may be the cause of increased vulnerability of the elderly to respiratory infections. The effect of oral intake of lactic acid bacteria on salivary secretory IgA (SIgA) in the elderly has not been reported. The objective of this study was to demonstrate the acceleration of salivary SIgA secretion by oral intake of Lactobacillus pentosus strain b240 (b240) in the elderly.

Results

A total of 80 healthy elderly individuals were randomly allocated to either an intervention (i.e., b240) or a control (i.e., placebo) group. The elderly individuals in the b240 group were given a sterile water beverage (125 mL) containing heat-killed b240 (4 × 109 cells), while those in the placebo group were given only a sterile water beverage (125 mL); both groups received their respective beverages once daily for 12 weeks. Saliva was collected before initiation of the study and every 2 weeks thereafter. Saliva flow rate and SIgA concentration were determined, and the SIgA secretion rate was calculated. The mean salivary SIgA secretion rate in the b240 group steadily increased until week 4 (exhibiting a 20% elevation relative to that at week 0), and then remained stable until week 12. Changes in SIgA secretion rate over the intervention period were significantly greater in the b240 group than in the placebo group. The treatment groups exhibited no significant differences in adverse events.

Conclusions

Oral intake of L. pentosus strain b240 for 12 weeks significantly accelerated salivary SIgA secretion, thereby indicating its potential utility in the improvement of mucosal immunity and resistance against infection in the elderly.  相似文献   
70.
To examine the biotransformation of Deoxynivalenol (DON) by the normal gut flora of pigs (in reliance on toxin-source) an in-vitro system was established. Suspensions of rectum contents from different treated animals were incubated with pure DON. Despite fast adaptation of microflora (Deepoxidation of DON) of animals fed wheat diet, no effects on reduced feed consumption and weight gain were seen. Even fast adaptation of microflora (lower intestine) couldn’t avoid DON-effects in vivo.  相似文献   
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