A biotin-avidin-linked immunosorbent assay was developed to detect Aspergillus antigens in sera of immunocompromised patients. The assay was based on a double antibody sandwich ELISA using polyclonal antibodies raised against water-soluble antigens of Aspergillus fumigatus. Aspergillus antigens were positive in sera of 9 of 16 (56%) patients who were studied prospectively and in 13 of 73 (19%) patients studied retrospectively. The 9 prospectively studied patients who were antigen positive were febrile neutropenic hematological malignancy patients who exhibited a high risk of acquiring invasive aspergillosis.
Antigens ; assay ; Aspergillus ; Immunocompromised Host ; Biotin

Biotin-deficient rats were raised on a purified ration containing raw egg white plus avidin. Urea synthesis and excretion were compared between the biotin-deficient and the pair-fed control rats. 24hrurinary urea excretion and the specific activities of carbamylphosphate synthetase, ornithine transcarbamylase, and arginase in the liver mitochondria fraction were no different between these two groups. The net urea production in the liver slice and in the isolated perfused liver of the biotin-deficient rats was similar to that of the pair-fed control. Thus the conclusion must be that biotin is not in urea in mea biosynthesis in the rat.
Animal ; Avitaminosis/metabolism ; Biotin* ; Liver/metabolism* ; Rats ; Urea/biosynthesis* ; MH - ; Substances: ; Urea ; Biotin

We induced apoptosis in normal rats by intramuscular injection of 5-fluorouracil (5-FU) and immunohistochemically evaluated the thymus for the TdT-mediated dUTP biotin nick end labelling on the 1st, 3rd, 6th, 9th, 15th and 21st days following the bolus intramuscular injection. The injections of 5-FU induced a greater extent of apoptosis in the thymus. In the thymus, a mild increase in apoptosis was observed 24 hours after injection. The greatest number of apoptotic cells were seen at 72 hours. The size of the thymus decreased and the cortex thinned with hypocellularity. The injection of 5-FU caused massive cell loss in the thymus. Most apoptotic cells were scattered in the cortex and lower levels of apoptosis were also observed in the medulla. After 72 hours, the level of apoptosis returned to the control level. Considering the above results, we think that 5-FU induced toxicity may be related to 5-FU induced apoptosis in normal tissue, especially the thymus.
Animals ; Apoptosis* ; Biotin ; Fluorouracil* ; Injections, Intramuscular* ; Rats* ; Thymus Gland*

Objective To compare the sensitivity and accuracy of amplified luminescent proximity homogeneous assay linked immunosorbent assay (AlphaLISA) and magnetic particles-based chemiluminescence immunoassay (MP-CLIA) for detection of staphylococcal enterotoxin C (SEC) in the simulated milk samples. Methods The AlphaLISA was constructed using goat anti-SEC polyclonal antibody-coupled receptor microspheres, biotin-labeled SEC monoclonal antibody and streptavidin-coupled donor microspheres. The MP-CLIA was constructed using goat anti-SEC polyclonal antibody conjugated alkaline phosphatase, biotin-labeled anti-SEC monoclonal antibody and streptavidin conjugated magnetic beads. Results The sensitivity of AlphaLISA to detect SEC content in simulated milk samples was 4.04 ng/L, and the coefficient of variation (CV) was 1.98%~9.82%. The sensitivity of MP-CLIA was 108.19 ng/L and CV was 4.63%~20.40%. Conclusion Compared with MP-CLIA, AlphaLISA is more sensitive and accurate to detecting SEC.
Animals ; Streptavidin ; Biotin ; Luminescence ; Milk ; Antibodies, Monoclonal ; Goats ; Immunoassay/methods*

To evaluate prognostic significance of p53 gene mutation and p53 protein overexpression, 83 cases of primary gastric carcinoma (stage 1b, II, and III) were analyzed. Immunohistochemical assay using labeled streptavidine biotin method and mouse Anti-P53 was done on paraffin embedded tissues. The overall 5-year survival rate was 54.2%. Depth of invasion, lymph node metastasis, and stage were the prognostic factors (p<0.05). p53 was positive in 33 cases(39.8%). There were no significant association between p53 expression and other parameters such as age, sex, tumor location, size, gross finding, histologic type, depth of invasion, lymph node metastasis, and stage. The 5-year survival rates of p53 positive and negative groups were 62% and 42.4% respectively (p=0.0657). Survival distribution for p53 adjusted for location and depth of invasion showed significant difference. Five-year survival rates were 55%, 25%, 0% in p53 positive groups and 65.4%, 65%, 28% in negative groups at the lower, middle, and upper portion of the stomach, and 53.9%, 36.9%, 0% in p53 positive and 77.3%, 53%, 0% in negative groups in t2, t3 and t4. In comparison of 5-year survival rates of p53 positive and negative groups in the same stage, p53 positive groups showed worse prognosis than the negative, but they were not significant statistically. There were 57.1%, 92.9% in stage 1b (p=0.0678), 50%, 61.1% in stage II, 42.9%, 42.9% in stage IIIa, and 14.3%, 25% in stage IIIb respectively. So overexpression of p53 protein has little prognostic significance.
Animals ; Biotin ; Genes, p53 ; Lymph Nodes ; Mice ; Neoplasm Metastasis ; Paraffin ; Prognosis ; Stomach ; Streptavidin ; Survival Rate

The located culture of cells on patterned surfaces is useful for tissue engineering, biosensor development and fundamental research of cell biology. It is presented here a rapid fabrication method of Biotin-Avidin protein layers micropattern, which is based on soft-lithography technology. The bovine aortic endothelial cells are cultured on the micropatterned surface. It is found that cell location can be controlled on the scale of individual cell by this method.
Animals ; Avidin ; metabolism ; Biotin ; metabolism ; Cattle ; Cells, Cultured ; cytology ; Tissue Engineering

In this experiment, a novel biotin-avidin conjugation probe was synthesized and employed in the detection of reverse-phase protein microarray. Firstly, the proportion of the biotin-avidin conjugation probe was optimized. Then the rat IgG and goat anti-rat IgG system was served as a model to optimize the fabrication conditions of reverse-phase protein microarray, including the non-specific absorption of streptavidin-Cy3 molecules, spotting buffer as well as protein activities. At last, the biotin-avidin conjugation probe was applied to the detection of the reverse-phase protein microarray. The results show that the protein microarray prepared by using BSA spotting buffer could prevent non-specific absorptions of fluorescent molecules and improve the sensitivity, effectively. In addition, compared with traditional biotin-avidin system, the detection limit could be improved four times using the biotin-avidin conjugation probe. In conclusion, the biotin-avidin conjugation probe has its merits of easy synthesis, low price and could be further conjugated with other signal amplification techniques, which is promising to be used in the detection of protein microarray.
Avidin ; chemistry ; Biotin ; chemistry ; DNA Probes ; Immunoglobulin G ; analysis ; immunology ; Protein Array Analysis ; methods

3-Methylcrotonyl-CoA carboxylase(MCC) is a biotin-dependent enzyme involved in the leucine metabolism. We describe a patient with MCC deficiency who manifested with Reye syndrome-like illness with status epilepticus, metabolic acidosis, hypoglycemia, hyperammonemia, elevated liver enzymes and neurologic impairments after a viral gastroenteritis and then suffered from Lennox-Gastaut syndrome. Urinary organic acid analysis revealed increased excretions of 3-hydroxyisovaleric acid and 3-methylcrotonylglycine. This patient was managed with a leucine restriction diet and supplementation of biotin and carnitine, which was not so effective. He suffered from neurologic sequelae such as Lennox-Gastaut syndrome, motor and cognitive impairements.
Acidosis ; Biotin ; Carnitine ; Diet ; Gastroenteritis ; Humans ; Hyperammonemia ; Hypoglycemia ; Leucine ; Liver ; Metabolism ; Status Epilepticus

Ageing is the most significant risk factor for a range of prevalent diseases, including cancer, cardiovascular disease, and diabetes. Accordingly, interventions are needed for delaying or preventing disorders associated with the ageing process, i.e., promotion of healthy ageing. Calorie restriction is the only nongenetic and the most robust approach to slow the process of ageing in evolutionarily divergent species, ranging from yeasts, worms, and flies to mammals. Although it has been known for more than 80 years that calorie restriction increases lifespan, a mechanistic understanding of this phenomenon remains elusive. Yeast silent information regulator 2 (Sir2), the founding member of the sirtuin family of protein deacetylases, and its mammalian homologue Sir2-like protein 1 (SIRT1), have been suggested to promote survival and longevity of organisms. SIRT1 exerts protective effects against a number of age-associated disorders. Caloric restriction increases both Sir2 and SIRT1 activity. This review focuses on the mechanistic insights between caloric restriction and Sir2/SIRT1 activation. A number of molecular links, including nicotinamide adenine dinucleotide, nicotinamide, biotin, and related metabolites, are suggested to be the most important conduits mediating caloric restriction-induced Sir2/SIRT1 activation and lifespan extension.
Biotin ; Caloric Restriction* ; Cardiovascular Diseases ; Diptera ; Humans ; Longevity ; Mammals ; NAD ; Negotiating ; Niacinamide ; Risk Factors ; Sirtuins ; Yeasts

Photoaffinity labeling is widely applied to demonstrate targets of small molecule ligands. In this paper, biotin photoaffinity labeled molecule with propargyl group 1 has been designed and synthesized, followed it's labeling of N2-acetyl-2'-O-propargyl guanosine 9 by "click chemistry". This technology presents delight development potential in labeling of second messenger cyclic nucleotide, antisense oligonucleotide or siRNA.
Biotin ; chemistry ; Click Chemistry ; Guanosine ; chemical synthesis ; chemistry ; Ligands ; Photoaffinity Labels