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Journal Article 2009; 30(Suppl 1): 72-79 PubMed PMID: 20027148 Citation  Keywords:  Absorption, Amino Acid Sequence, Animals, Apoproteins:chemistry, Butanones, Chromatography, Cytochromes b5:chemistry, Electrons, Electrophoresis, Polyacrylamide Gel, Heme:chemistry, Horses, Hydrogen-Ion Concentration, Mass Spectrometry, Molecular Sequence.   

OBJECTIVES: Cytochrome b5 (cyt b5), a component of endoplasmic reticulum membrane, plays a role in modulation of activity of several cytochromes P450 (CYP). To elucidate the mechanism of such modulations it is necessary to evaluate not only the effect of native cyt b5, but also that of apo-cyt b5. To prepare apo-cyt b5, heme transfer from native cyt b5 to a protein with higher affinity toward the heme, the horse heart apo-myoglobin, was utilized.

METHODS: Butanone extraction was employed to prepare apo-myoglobin. Apo-cyt b5 was separated from myoglobin by chromatography on DEAE-Sepharose. Mass spectrometry was utilized to characterize proteins eluted from DEAE- Sepharose.

RESULTS: The prepared apo-myoglobin was incubated with the cyt b5 at pH 4.2 that is the optimal pH for heme transfer from cyt b5 into apo-myoglobin. The apo-cyt b5 protein was separated from myoglobin present in the reaction mixture by chromatography on a column of DEAE-Sepharose. Using such a procedure, 16% yield of apo-cyt b5 that did not contain any heme in its molecule was obtained from the native rabbit cyt b5. Oxidized and reduced forms of the apo-b5 reconstituted with heme exhibit the same absorbance spectra as native cyt b5. The prepared apo-cyt b5 reconstituted with heme can receive electrons from NADPH:CYP reductase.

CONCLUSION: A biologically active apo-cyt b5 was prepared using transfer of heme from cyt b5 to horse heart apo-myoglobin by the procedure described here....

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Case Reports 2007; 28(5): 545-546 PubMed PMID: 17984955 Citation  Keywords:  Adolescent, Angelman Syndrome:complications, Child, Preschool, Chromosomes, Human, Pair 15:genetics, Humans, Hypothyroidism:blood, Immunoglobulins, Thyroid-Stimulating:blood, Sequence Deletion, Thyroxine:therapeutic use,.   

: Angelman Syndrome (AS, MIM 105830), classified among neurogenetic disorders, occurs with estimated frequency of 1:10 000 to 1:40 000. The characteristics features apart from neurodevelopmental impairment and seizures include peculiar face traits, absent speech, outburst of laughter, ataxia, stereotyped jerky (puppet-like) movements. The authors report three children with Angelman syndrome who were also diagnosed with hypothyroidism....

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Journal Article 2003; 24(1-2): 39-45 PubMed PMID: 12743530 Citation  Keywords:  Amino Acid Sequence, Animals, Annelida:chemistry, Anti-Bacterial Agents, Bacteria:drug effects, Cloning, Molecular, DNA, Complementary:biosynthesis, Electrophoresis, Polyacrylamide Gel, Enzyme-Linked Immunosorbent Assay, Escherichia coli:drug effects, Gra.   

OBJECTIVES: To investigate the immune defense of the annelid Nereis diversicolor and the key role of a oxygen-binding protein, the metalloprotein MPII animals were subjected to bacteria infection.

METHODS AND RESULTS: Using RACE-PCR, we have cloned the complete cDNA coding for the MPII related to the hemerythrin family in the sand worm Hediste diversicolor. This cDNA (883 pb) codes for a polypeptide of 119 amino acid residues with no signal peptide. Previous works have identified this protein as a cadmium scavenger. We here clearly demonstrated that this protein is also involved in the worm defence towards bacteria growth by its iron scavenger ability. This protein is expressed and produced in a haematopoietic center that floats freely in the coelomic fluid before stored in a particular hemocyte type: the granulocyte type 1. During bacterial challenge, this protein contained in these cells is discharged into the blood stream 3-4 hours after the infection and remains active for approximately 10 hours. This time period blocks progression of the pathogen and its attachment to tissues.

CONCLUSION: These results reflect that MPII in conjunction with others partners like lysozyme act as defence molecule for the sand worm....

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Journal Article 2018; 39(4): 299-304 PubMed PMID: 30531708 Citation  Keywords:  Animals, Embryo, Nonmammalian:drug effects, Gelatin, Lethal Dose 50, Maltose, Nanoparticles, Povidone, Silver:toxicity, Silver Nitrate:toxicity, Zebrafish,.   

OBJECTIVES: The aim of this study was to establish and evaluate the mortality rate, hatching rate and observe the presence of sublethal changes in zebrafish embryos after exposure to silver ions and nanoparticles. METHODS: Tests were conducted on newly fertilized zebrafish embryos, according to the modified OECD guideline 236, using a semistatic method and 96 hour incubation time. Silver nitrate and two different silver nanoparticles, stabilized with 0.01% solution of maltose and gelatine in the first case, and stabilized with polyvinylpyrrolidone, in the latter, were tested. RESULTS: Significant differences in toxicity of tested substances were recorded. The value of 96hLC50 for silver nitrate was 58.44 μg/L. The value of 96hLC50, calculated for silver nanoparticles stabilized with 0.01% solution of maltose and gelatine, was nearly 100 times higher, 4.31 mg/L. The value 96hLC50 for silver nanoparticles stabilized with polyvinylpyrrolidone exceeded 100mg/L, occurrence of sublethal effects caused by silver nanoparticles stabilized with polyvinylpyrrolidone was insignificant in most of the exposition groups, but only in this substance caused decreased hatching rate. CONCLUSION: Properties of different silver nanoparticles play an important role in levels of their toxicity and predominant mechanisms of action. In general, silver nanoparticles are less toxic for Danio rerio embryos than silver ions....

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