scholarly journals THE SEROLOGIC SPECIFICITY OF TROPOCOLLAGEN TELOPEPTIDES

1967 ◽  
Vol 126 (2) ◽  
pp. 331-346 ◽  
Author(s):  
Peter F. Davison ◽  
Lawrence Levine ◽  
Maurice P. Drake ◽  
Albert Rubin ◽  
Susan Bump
Keyword(s):  
Electron Microscopy ◽  
Heat Denaturation ◽  
Clinical Concern ◽  
Dependent Process ◽  
Serologic Reaction ◽  
Different Strains ◽  
Different Tissues ◽  
Serologic Specificity

Tropocollagen preparations from carp, buffalo fish, rats, calves, sheep, and humans have been studied by electron microscopy and serologic methods. Tropocollagens from each species appeared identical by electron microscopy but they were readily distinguished (except between sheep and calves) by C'-fixation tests with rabbit antisera against the various tropocollagens. Tests with calf tropocollagen antiserum showed no distinction between tropocollagen isolated from different tissues nor between individuals of the same or different strains. The major immunogenic sites in native tropocollagen are the telopeptides, and these are present on both α1- and α2-chains. The C'-fixing activity was lost with heat denaturation of the tropocollagen, but could be recovered in a concentration-dependent process on cooling. The fact that pure and enzyme-treated collagen can provoke serologic reaction implies that collagenous sutures and prostheses used in surgery may lead to sensitization and rejection, a fact which may merit clinical concern.

The cheesemaking potential of milk concentrated up to four-fold by ultrafiltration and heated in the range 90–97 °C

1990 ◽  
Vol 57 (4) ◽  
pp. 549-557 ◽  
Author(s):  
Margaret L. Green
Keyword(s):  
Electron Microscopy ◽  
Heat Treatment ◽  
Whey Protein ◽  
Protein Interactions ◽  
Heat Denaturation ◽  
The Difference

SummaryProperties of interest to cheesemaking were investigated with milks concentrated by ultrafiltration and heated at 90 °C or 95–97 °C for 15 s. The effects of light homogenization before concentration and of addition of CaCl2 after heating were assessed. No changes in casein–fat or casein–whey protein interactions were detected by electron microscopy. The heat denaturation of whey protein increased linearly as the milk became more concentrated. Coagulability by rennet after heat treatment increased with concentration to close to the unheated value in 3·5 to 4-fold concentrates. The decrease in curd firming rate by heat treatment was slightly affected by concentration and addition of CaCl2 restored some of the difference. Heat treatment reduced the rate of whey loss and slightly improved the curd structure but did not affect fat losses. Light homogenization slightly reduced heat denaturation of whey protein and whey loss.

scholarly journals Isolation of Enterococcus faecalis Clinical Isolates That Efficiently Adhere to Human Bladder Carcinoma T24 Cells and Inhibition of Adhesion by Fibronectin and Trypsin Treatment

1999 ◽  
Vol 67 (4) ◽  
pp. 1585-1592 ◽  
Author(s):  
Akihiko Shiono ◽  
Yasuyoshi Ike
Keyword(s):  
Electron Microscopy ◽  
Enterococcus Faecalis ◽  
Specific Protein ◽  
Cell Surfaces ◽  
Trypsin Treatment ◽  
Human Bladder ◽  
T24 Cells ◽  
Different Strains ◽  
Tract Infections ◽  
Scanning Electron

ABSTRACT The adherence of Enterococcus faecalis strains to human T24 cells was examined by scanning electron microscopy. Five highly adhesive strains were identified from 30 strains isolated from the urine of patients with urinary tract infections. No efficiently adhesive strains were found among the 30 strains isolated from the feces of healthy students. The five isolated strains also adhered efficiently to human bladder epithelial cells. Analysis of restriction endonuclease-digested plasmid DNAs and chromosome DNAs showed that the five strains were different strains isolated from different patients. The adhesiveness of these strains was inhibited by treatment with fibronectin or trypsin, implying that a specific protein (adhesin) on the bacterial cell surface mediates adherence to fibronectin on the host cell surfaces, and the adhesin differs from the reported adhesins.

scholarly journals Binding of laminin to type IV collagen: a morphological study.

1985 ◽  
Vol 100 (6) ◽  
pp. 1848-1853 ◽  
Author(s):  
A S Charonis ◽  
E C Tsilibary ◽  
P D Yurchenco ◽  
H Furthmayr
Keyword(s):  
Electron Microscopy ◽  
Morphological Study ◽  
Type Iv Collagen ◽  
Specific Binding ◽  
Terminal Region ◽  
The Other ◽  
Heat Denaturation ◽  
Type Iv ◽  
Nc1 Domain ◽  
Rotary Shadowing

A mixture of laminin and type IV collagen was analyzed by rotary shadowing using carbon/platinum and electron microscopy. Laminin was found to form distinct complexes with type IV collagen: one site of interaction is located 140 nm from the COOH-terminal, noncollagenous (NC1) domain and the other is located within the NH2-terminal region. The isolated NC1 fragment of type IV collagen does not appear to interact with laminin, while pepsin-treated type IV collagen, which lacks the NC1 domain, retains its ability to form complexes with laminin. Analysis of the laminin-type IV complexes indicates that laminin binds to type IV collagen via the globular regions of either of its four arms. This finding is supported by experiments using fragment P1 of laminin which lacks the globular regions and which does not bind to type IV collagen in a specific way. In addition, after heat-denaturation of laminin no specific binding is observed.

The Influence of Ca2+ and Zn2+ on the Amyloid Fibril Formation by β-Casein

2020 ◽  
Vol 27 (9) ◽  
pp. 915-922
Author(s):  
Jia Wang ◽  
Jihua Liu ◽  
Guangguang Du ◽  
Yang An ◽  
Chunfang Zhao ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Amyloid Fibril ◽  
Fibril Formation ◽  
Intrinsic Fluorescence ◽  
Amyloid Fibril Formation ◽  
Transmission Electron ◽  
Concentration Changes ◽  
Set Up ◽  
The Relationship ◽  
Different Tissues

Background: The amyloid fibril formation in different tissues or organs is related to amyloidosis. The Ca2+, Zn2+ and heparan sulfate (HS) are important elements and compositions in human body, which play a key role in regulating various physiological activities. Recently, there are increasing evidence suggest that they are closely linked to the amyloid fibril formation. Objective: The effect of Ca2+ and Zn2+ on the amyloid fibril formation by β-casein was investigated in the absence and presence of HS, which was significantly to explore the relationship between the concentration changes of Ca2+ and Zn2+ and amyloid fibril formation. Method: In this work, the influence of Ca2+ and Zn2+ on the β-casein fibril formation in the absence and presence of HS was investigated by various methods of Thioflavin T fluorescence assay, transmission electron microscopy and intrinsic fluorescence measure. Results: The results demonstrated that Ca2+ and Zn2+ promoted the β-casein fibril formation. The effect of Ca2+ was greater than that of Zn2+. Meanwhile, the both metal ions had stronger effects when β-casein was incubated with HS together. In addition, it was also observed that the microenvironment of β-casein was changed because the intrinsic fluorescence peaks were red-shifted on the influence of Ca2+ and Zn2+. Conclusion: Ca2+ and Zn2+ were capable of promoting the β-casein fibril formation in the both absence and presence of HS. This work set up the foundation for further researching of the amyloidosis pathogenesis and provided new insight for us to understand relationship between the inflammation and amyloidosis.

scholarly journals THE FORM AND STRUCTURE OF KINETOPLAST DNA OF CRITHIDIA

1972 ◽  
Vol 54 (2) ◽  
pp. 346-364 ◽  
Author(s):  
Hartmut C. Renger ◽  
David R. Wolstenholme
Keyword(s):  
Electron Microscopy ◽  
Cesium Chloride ◽  
Contour Length ◽  
Main Band ◽  
Thin Sections ◽  
Group A ◽  
Linear Molecules ◽  
Different Strains ◽  
Topological Interlocking

Cesium chloride centrifugation of each of the DNAs extracted from eight strains of Crithidia revealed a main band at ρ = 1.717 g/cm3 and a satellite band varying from ρ = 1.701 to 1.705 g/cm3 for the different strains By electron microscopy each DNA was shown to include circular molecules, 0.69–0.80 µ in mean contour length, and large, topologically two-dimensional masses of DNA in which the molecules appeared in the form of rosettes. DNA isolated from kinetoplast fractions of Crithidia acanthocephali was shown to consist of light satellite DNA and to be mainly in the form of large masses, 0.8 µ (mol wt = 1.54 x 106 daltons) circular molecules, and a few long, linear molecules. The results of experiments involving ultracentrifugation, heating, and quenching, sonication, and endodeoxyribonuclease digestion, combined with electron microscopy, are consistent with the following hypothesis. The large DNA masses are associations of 0.8 µ circles which are mainly covalently closed. The circles are held together in groups (the rosettes) of up to 46 by the topological interlocking of each circle with many other circles in the group. A group of circles is attached to an adjacent group by one or more circles, each interlocking with many circles of both groups. Each of the associations comprises, on the average, about 27,000 circles (total mol wt ≃ 41 x 109 daltons). A model is proposed for the in situ arrangement of the associations which takes into consideration their form and structure, and appearance in thin sections

Atomic Force Microscopy and Scanning Electron Microscopy Reveal Genome–dependent Ultrastructure of Seed Surface

2001 ◽  
Vol 7 (6) ◽  
pp. 526-529
Author(s):  
T. Guha ◽  
R. Bhar ◽  
V. Ganesan ◽  
A. Sen ◽  
R.L. Brahmachary
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Atomic Force Microscopy ◽  
Contact Mode ◽  
Surface Ultrastructure ◽  
Force Microscopy ◽  
Seed Surface ◽  
Atomic Force ◽  
Different Strains ◽  
Scanning Electron

AbstractBoth scanning electron microscopy (SEM) and contact mode imaging via atomic force microscopy (AFM) have been utilized to elucidate the ultrastructure of mung bean seed surfaces. The results indicate: 1) that AFM is useful in the examination of seed surface ultrastructure ex-vaccuo without the need for additional complex preparative procedures; and 2) that both the cotyledon and seed coat of different strains of mung beans bear specific ultrastructural details unique to each strain. To our knowledge, these are the first AFM images of seed surfaces.

Immuno-electron microscopy of surface antigens of Bordetella pertussis

1988 ◽  
Vol 46 ◽  
pp. 314-315
Author(s):  
M. E. Bisher ◽  
M. J. Brennan ◽  
Z. M. Li ◽  
A. C. Steven
Keyword(s):  
Electron Microscopy ◽  
Bordetella Pertussis ◽  
Molecular Level ◽  
Whooping Cough ◽  
Surface Antigens ◽  
Negative Bacterium ◽  
Convenient Means ◽  
Immuno Electron Microscopy ◽  
Serotype 1 ◽  
Different Strains

Bordetella pertussis is the Gram-negative bacterium responsible for whooping-cough. To develop a better understanding of the interactions between B. pertussis and the cells of colonized tissues, as well as for purposes of vaccine design, much effort has been devoted to characterizing the antigenic molecules exposed at its outer surface. A set of six U.S. Reference Factor Antisera raised by Eldering recognize agglutinogens that are specific to B. pertussis. Since each strain exhibits a particular subset of these antigens, the antisera provide a convenient means of classifying different strains of this bacterium. Several of these antigens have been identified at the molecular level. Serotype 1 agglutinogen is associated with a lipo-oligosaccharide, and those of serotypes 2 and 6 are fimbriae of two morphologically similar but antigenically distinct kinds. Recently, it has been demonstrated serotype 3 antiserum recognizes a 69kDa protein. To characterize the distribution of this antigen in and around B. pertussis cells, we have performed immuno-gold electron microscopy, using monoclonal antibodies raised against the 69kDa protein.

scholarly journals Biochemical variation in purebred and crossbred strains of domestic rabbits (Oryctolagus cuniculus L.)

1986 ◽  
Vol 48 (1) ◽  
pp. 27-34 ◽  
Author(s):  
G. B. Hartl ◽  
H. Höger
Keyword(s):  
Genetic Variation ◽  
Gel Electrophoresis ◽  
Oryctolagus Cuniculus ◽  
Mammalian Species ◽  
Starch Gel Electrophoresis ◽  
Starch Gel ◽  
Biochemical Variation ◽  
Domestic Rabbits ◽  
Different Strains ◽  
Different Tissues

SummaryGenetic variation in 40 domestic rabbits (Oryctolagus cuniculus) from eight different strains was investigated by horizontal starch gel electrophoresis. Twenty nine enzyme systems were examined in different tissues, 10 isoenzymes were found to be polymorphic. Indices of genetic variation show values comparable to those found in most other mammalian species. Thus the unusually high values reported previously by other authors may be due to a limited and not randomly chosen set of enzymes studied.

Sign in / Sign up

Export Citation Format

Share Document