What's the difference between keratin and protein?

Keratin


Definition:

  • (n.) A nitrogenous substance, or mixture of substances, containing sulphur in a loose state of combination, and forming the chemical basis of epidermal tissues, such as horn, hair, feathers, and the like. It is an insoluble substance, and, unlike elastin, is not dissolved even by gastric or pancreatic juice. By decomposition with sulphuric acid it yields leucin and tyrosin, as does albumin. Called also epidermose.

Example Sentences:

  • (1) The observed staining indicated that the epithelium of the external auditory meatus has a pattern of keratin expression typical of epidermis in general and the epithelium of the middle ear resembles simple columnar epithelia.
  • (2) A new method of staining the keratin filament matrix allowing a visualization of the filaments in cross section of hair fibres has been developed.
  • (3) The positive reaction for keratin and vimentin confirmed the presence of ectodermal and mesodermal elements respectively in the tumor.
  • (4) The mean gain in width of keratinized gingiva averaged 3.15 mm.
  • (5) The histological changes by light and electron microscopy in these patients demonstrates the metaplastic changes of the basal cell of the mucosa differentiating into mucous and keratin cells.
  • (6) These particular keratins that were found among others in basal cells could also be detected to a variable extent in metaplastic and dysplastic cervical lesions.
  • (7) Chemically isolated separate preparations of the non-aggregating protein-chondroitin-keratin sulphate (PCKS) fraction from the hyaline cartilage and hyaluronic acid (HUA) of the vitreous body and of the umbilicus were investigated by electron microscopy.
  • (8) In benign lesions both keratins were present, while in malignant ones only keratin No.
  • (9) The diagnosis was defined by immunohistochemical methods, which showed a positivity for keratin in the cells lining spaces with a vascular appearance.
  • (10) All of the cell lines expressed keratin intermediate filaments and two showed weak co-expression of vimentin.
  • (11) The expression of keratin and differentiation markers was identical to that of normal keratinocytes, suggesting that psoriatic epidermal differentiation is not truncated in vitro as has been postulated to be the case in vivo.
  • (12) In seven out of eight patients, the urothelium adjacent to the squamous cell metaplasia was also positive for keratin, indicating a direct transformation of the urothelium to squamous cell epithelium.
  • (13) Carcinomas fail to express suprabasal cell keratins and this is regulated at the transcriptional level.
  • (14) Lactobacillus strains of numerous species isolated from several animal sources exhibited cellular hydrophobicities that differed from those expected on the basis of their abilities to colonize the keratinizing stratified squamous epithelium in the mouse stomach.
  • (15) Furthermore the presence of keratin 17 in a CIN I, II, or III lesion may indicate progressive potential while its absence could be indicative of a regressive behavior.
  • (16) We did not observe two distinct types of cells with different morphology or components which could be held responsible for the production of two different types of keratin as have been described in other animals, but rather a uniformity of cell structures in each layer and only the so-called "smooth" type of keratin.
  • (17) The present study compares different post-embedding staining methods, including conventional and low-temperature embedding techniques, for demonstration of the keratin and vimentin cytoskeleton of epidermal cells, applying commercially available polyclonal and monoclonal antibodies.
  • (18) All cases so examined had positive results for vimentin and negative results for keratin.
  • (19) We have examined the keratin proteins in normal human oral mucosa from 6 different regions including hard palate, buccal mucosa, tongue, gingiva and floor of the mouth.
  • (20) Expression of keratins of high molecular weight was reduced to small foci of keratinization and scattered dyskeratotic cells.

Protein


Definition:

  • (n.) A body now known as alkali albumin, but originally considered to be the basis of all albuminous substances, whence its name.

Example Sentences:

  • (1) All mutant proteins could associate with troponin I and troponin T to form a troponin complex.
  • (2) By electrophoresis and scanning densitometry, actin was found to constitute about 4% to 6% of the total cellular protein in the human corneal epithelium.
  • (3) Comparison of the S100 alpha-binding protein profiles in fast- and slow-twitch fibers of various species revealed few, if any, species- or fiber type-specific S100 binding proteins.
  • (4) Standardization is possible after correction by the protein content of each individual section.
  • (5) The hypothesis that proteins are critical targets in free radical mediated cytolysis was tested using U937 mononuclear phagocytes as targets and iron together with hydrogen peroxide to generate radicals.
  • (6) These studies led to the following conclusions: (a) all the prominent NHP which remain bound to DNA are also present in somewhat similar proportions in the saline-EDTA, Tris, and 0.35 M NaCl washes of nuclei; (b) a protein comigrating with actin is prominent in the first saline-EDTA wash of nuclei, but present as only a minor band in the subsequent washes and on washed chromatin; (c) the presence of nuclear matrix proteins in all the nuclear washes and cytosol indicates that these proteins are distributed throughout the cell; (d) a histone-binding protein (J2) analogous to the HMG1 protein of K. V. Shooter, G.H.
  • (7) Following central retinal artery ligation, infarction of the retinal ganglion cells was reflected by a 97 per cent reduction in the radioactively labeled protein within the optic nerve.
  • (8) Increased dietary protein intake led to increased MDA per nephron, increased urinary excretion of MDA, and increased MDA per milligram protein in subtotally nephrectomized animals, and markedly increased the glutathione redox ratio.
  • (9) The presence of O-glycosidic linkages between carbohydrate and protein in the DF3 antigenic site was further supported by the presence of NaBH4-sensitive sites.
  • (10) Cyclic AMP stimulated phosphorylation by [gamma-32P]ATP of two proteins of apparent Mr = 20,000 and 7,000 that were concentrated in sarcoplasmic reticulum, but the stimulation was markedly dependent on the presence of added soluble cyclic AMP-dependent protein kinase.
  • (11) The quaternary structure of ribonucleotide reductase of Escherichia coli was investigated, with the use of purified B1 and B2 proteins and bifunctional cross-linking agents.
  • (12) This induction is sensitive to actinomycin D but not to protein synthesis inhibitor puromycin, indicating an effect of estradiol at the transcriptional level, possibly mediated by the estrogen receptor.
  • (13) The promoters of the adenovirus 2 major late gene, the mouse beta-globin gene, the mouse immunoglobulin VH gene and the LTR of the human T-lymphotropic retrovirus type I were tested for their transcription activities in cell-free extracts of four cell lines; HeLa, CESS (Epstein-Barr virus-transformed human B cell line), MT-1 (HTLV-I-infected human T cell line without viral protein synthesis), and MT-2 (HTLV-I-infected human T cell line producing viral proteins).
  • (14) This clinical improvement was also associated with a decrease of erythrocyte sedimentation rate (p less than 0.001), decrease of C-reactive protein (p less than 0.0001) and with improvement of anaemia (p less than 0.05).
  • (15) The mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis is anomalous since the undenatured, cross-linked proteins have the same Stokes radius as the native, uncross-linked alpha beta gamma heterotrimer.
  • (16) We also show that the gene of the main capsid protein is expressed from its own promoter in an Escherichia coli strain.
  • (17) Western blot analysis of these mitochondria using an antibody against carnitine palmitoyltransferase II purified from beef heart demonstrates a 68-kDa protein, which under ischemic conditions apparently is decreased by 2 kDa.
  • (18) Fifteen sera ICA-IgG and ICA-protein A positive with high titres remained positive thereafter.
  • (19) Patient or fetal cord serum is commonly used as a protein supplement to culture media used in in-vitro fertilization (IVF).
  • (20) Using the oocyte system to express size-fractionated mRNA, we have also determined that the mRNA coding for this protein is between 1.9-2.4 kilobases in length.