Postirradiation recovery of haemopoiesis in Steel mutant mice

The recovery of haemopoiesis in Steel mutant mice following 1 Gy sublethal irradiation is described. Steel homozygotes (S1/S1) did not display the abortive phase of erythropoietic recovery while the secondary phase of erythropoietic recovery was more pronounced in S1/S1 than in control (+/+) animals. On the contrary, the neutrophilopoietic recovery in S1/S1 mice was defective only during the secondary phase of recovery. Steel heterozygotes (S1/+) manifested similar, albeit less pronounced, defects. In the course of studies of recovery of eosioniphils it was observed that neither wild-type nor mutant animals expressed the abortive rise. Moreover, the kinetics of recovery of eosinophils was essentially different from both erythropoietic and neutrophilopoietic recovery, and the preirradiation level was reached in both normal and mutant animals on day 60 postirradiation as opposed to 24 and 35 days for erythropoiesis and neutrophils respectively.     

Chemical characterization by protein sequence analysis of the bovine estrogen receptor

Tryptic peptides generated from bovine estrogen receptor have been fractionated and purified using microbore column high performance liquid chromatography. Sequence analysis performed on six of these peptides, derived from diverse structural regions of the receptor protein, yielded 73 unique assignments corresponding to approximately 12% of the molecule. The amino acid sequences of these peptides displayed a high degree of similarity with corresponding sequences from estrogen receptors of mammalian origin, but were only moderately conserved in receptors from non-mammalian species. The sequenced residues of one tryptic peptide, positioned in the estrogen binding domain, were fully conserved in all estrogen receptors.     

Organization and results of mass screening for congenital hypothyroidism in newborn infants in the Cracow province

Screening for congenital hypothyroidism has been carried out in 69,286 newborn children born in the region and city of Krakow in the years 1985-1988. Fourteen cases of congenital thyroid insufficiency were detected indicating the incidence of 1:4816 in this region. In 25 newborns (incidence of 1:1979) a transient hyperthyreotropinemia was diagnosed. It was concluded that the main reason of the appearance of an elevated TSH level in newborns of this region seems to be the deficiency of iodine in the diet and/or environment.     

Induction of the murine “W phenotype” in long-term cultures of human cord blood cells by c-kit antisense oligomers

The murine white (W) spotting locus is the site of the c-kit gene and encodes a tyrosine kinase receptor while the complementary Steel (Sl) iocus encodes its ligand. Mutations at either locus have profound effects on hematopoiesis, particularly erythroid and mast cell proliferation. We added c-kit antisense oligonucleotides to long-term suspension cultures of enriched human umbilical cord progenitor cells. This resulted in the suppression of c-kit gene expression and the preferential suppression of the generation of erythroid burst-forming cells (BFU-E) which extended over the life of the culture (3 weeks). The results provide an in vitro model of the “W phenotype” in human hematopoiesis and confirm the importance of c-kit gene function in early erythropoiesis. Because the generation of BFU-E was suppressed even after c-kit gene expression had recovered, this gene product may be critical to the erythroid commitment process. © 1993 Wiley-Liss, Inc.     

Aptamer-functionalized quantum dots as theranostic nanotools against cancer and bacterial infections: A comprehensive overview of recent trends

Aptamers (Apts) are synthetic nucleic acid ligands that can be engineered to target various molecules, including amino acids, proteins, and pharmaceuticals. Through a series of adsorption, recovery, and amplification steps, Apts are extracted from combinatorial libraries of synthesized nucleic acids. Using aptasensors in bioanalysis and biomedicine can be improved by combining them with nanomaterials. Moreover, Apt-associated nanomaterials, including liposomes, polymeric, dendrimers, carbon nanomaterials, silica, nanorods, magnetic NPs, and quantum dots (QDs), have been widely used as promising nanotools in biomedicine. Following surface modifications and conjugation with appropriate functional groups, these nanomaterials can be successfully used in aptasensing. Advanced biological assays can use Apts immobilized on QD surfaces through physical interaction and chemical bonding. Accordingly, modern QD aptasensing platforms rely on interactions between QDs, Apts, and targets to detect them. QD-Apt conjugates can be used to directly detect prostate, ovarian, colorectal, and lung cancers or simultaneously detect biomarkers associated with these malignancies. Tenascin-C, mucin 1, prostate-specific antigen, prostate-specific membrane antigen, nucleolin, growth factors, and exosomes are among the cancer biomarkers that can be sensitively detected using such bioconjugates. Furthermore, Apt-conjugated QDs have shown great potential for controlling bacterial infections such as Bacillus thuringiensis, Pseudomonas aeruginosa, Escherichia coli, Acinetobacter baumannii, Campylobacter jejuni, Staphylococcus aureus, and Salmonella typhimurium. This comprehensive review discusses recent advancements in the design of QD-Apt bioconjugates and their applications in cancer and bacterial theranostics.     

Innate immunity orchestrates the mobilization and homing of hematopoietic stem/progenitor cells by engaging purinergic signaling—an update

Purinergic Signalling - Bone marrow (BM) as an active hematopoietic organ is highly sensitive to changes in body microenvironments and responds to external physical stimuli from the surrounding...     

Effect of handling on ATP utilization of cerebral Na,K-ATPase in rats with trimethyltin-induced neurodegeneration

Molecular and Cellular Biochemistry - Previously it was shown that for reduction of anxiety and stress of experimental animals, preventive handling seems to be one of the most effective methods....     

Forest Saccharomyces paradoxus are robust to seasonal biotic and abiotic changes

Microorganisms are famous for adapting quickly to new environments. However, most evidence for rapid microbial adaptation comes from laboratory experiments or domesticated environments, and it is unclear how rates of adaptation scale from human‐influenced environments to the great diversity of wild microorganisms. We examined potential monthly‐scale selective pressures in the model forest yeast Saccharomyces paradoxus. Contrary to expectations of seasonal adaptation, the S. paradoxus population was stable over four seasons in the face of abiotic and biotic environmental changes. While the S. paradoxus population was diverse, including 41 unique genotypes among 192 sampled isolates, there was no correlation between S. paradoxus genotypes and seasonal environments. Consistent with observations from other S. paradoxus populations, the forest population was highly clonal and inbred. This lack of recombination, paired with population stability, implies that selection is not acting on the forest S. paradoxus population on a seasonal timescale. Saccharomyces paradoxus may instead have evolved generalism or phenotypic plasticity with regard to seasonal environmental changes long ago. Similarly, while the forest population included diversity among phenotypes related to intraspecific interference competition, there was no evidence for active coevolution among these phenotypes. At least ten percent of the forest S. paradoxus individuals produced “killer toxins,” which kill sensitive Saccharomyces cells, but the presence of a toxin‐producing isolate did not predict resistance to the toxin among nearby isolates. How forest yeasts acclimate to changing environments remains an open question, and future studies should investigate the physiological responses that allow microbial cells to cope with environmental fluctuations in their native habitats.