High molecular weight DNA from fixed cytogenetic preparations.

Cell pellets that have been stored in routine clinical cytogenetic fixative were studied for the presence of intact DNA. A method for the isolation of high molecular weight DNA from fixed cytogenetic preparations of human leukocytes, bone marrow, and cell hybrid cultures is presented. DNA preparations from fixed pellets were cleaved with restriction enzymes, transferred to nitrocellulose filters after agarose gel electrophoresis, and hybridized to radiolabeled probes to demonstrate that fixed cell pellets could yield DNA of sufficient quality for Southern blot hybridization analysis. This protocol may be useful for molecular analysis of DNA from fixed cell pellets of patients who are unavailable for additional sampling.     

Signaling by FGFR2b controls the regenerative capacity of adult mouse incisors

Rodent incisors regenerate throughout the lifetime of the animal owing to the presence of epithelial and mesenchymal stem cells in the proximal region of the tooth. Enamel, the hardest component of the tooth, is continuously deposited by stem cell-derived ameloblasts exclusively on the labial, or outer, surface of the tooth. The epithelial stem cells that are the ameloblast progenitors reside in structures called cervical loops at the base of the incisors. Previous studies have suggested that FGF10, acting mainly through fibroblast growth factor receptor 2b (FGFR2b), is crucial for development of the epithelial stem cell population in mouse incisors. To explore the role of FGFR2b signaling during development and adult life, we used an rtTA transactivator/tetracycline promoter approach that allows inducible and reversible attenuation of FGFR2b signaling. Downregulation of FGFR2b signaling during embryonic stages led to abnormal development of the labial cervical loop and of the inner enamel epithelial layer. In addition, postnatal attenuation of signaling resulted in impaired incisor growth, characterized by failure of enamel formation and degradation of the incisors. At a cellular level, these changes were accompanied by decreased proliferation of the transit-amplifying cells that are progenitors of the ameloblasts. Upon release of the signaling blockade, the incisors resumed growth and reformed an enamel layer, demonstrating that survival of the stem cells was not compromised by transient postnatal attenuation of FGFR2b signaling. Taken together, our results demonstrate that FGFR2b signaling regulates both the establishment of the incisor stem cell niches in the embryo and the regenerative capacity of incisors in the adult.     

Intervention based on BASNEF model increases exclusive breastfeeding in preterm infants in Iran: a randomized controlled trial

Background

The objective of this study is to determine the effect of a consultation model, Beliefs, Attitudes, Subjective Norms and Enabling Factors (BASNEF), and the counselling steps using GATHER-Greet clients, Ask clients about themselves, Tell clients about their choices, Help clients choose, Explain what to do, and Return for follow-up-on the continuation rates of exclusive breastfeeding in mothers of premature infants.

Methods

This is a randomized controlled clinical trial carried out on 124 mothers with premature infants hospitalized in Fatemieh Hospital, city of Hamadan, in 2014. Participants were randomly assigned to either the intervention or control groups. The initial demographic questionnaire carried out in both groups included three questions about the continuation of exclusive breastfeeding, BASNEF, a checklist related to the lactation performance documented by mothers and the weight gain of their infants. Five breastfeeding consultation sessions based on the BASNEF model and counselling steps using GATHER, were held for the mothers in the intervention group for five consecutive days. Then follow-up weight gain and the questionnaire completion were performed in both groups at 1, 2, 3 and 4 months after the intervention.

Results

Baseline characteristics were similar in the two groups. There were no significant differences between both groups in the rate of exclusive breastfeeding, lactation performance and infant weight at baseline. The intervention group had significantly higher rates of exclusive breastfeeding, 72.6% versus the control group of 16.1%, at the end of the 4 month follow-up. Also the intervention group had significantly higher mean scores of lactation performance (8.62?±?2.08 vs 6.40?±?1.84 in the control group) and infant weight (5694.80?±?779.43 vs 4760.17?±?859.12 in the control group) at the end of the 4 month follow-up.

Conclusion

Breastfeeding consultation of mothers based on the BASNEF model and using GATHER counselling steps increased the rate of exclusive breastfeeding, lactation performance and weight gain of premature infants. Therefore, breastfeeding counselling sessions are recommended for all mothers of premature infants.

Trial registration

Iranian Registry of Clinical Trials number IRCT2014111013405N6 and date registered, January 5, 2015.

     

Contrasting expression of canonical Wnt signaling reporters TOPGAL, BATGAL and Axin2(LacZ) during murine lung development and repair

Canonical WNT signaling plays multiple roles in lung organogenesis and repair by regulating early progenitor cell fates: investigation has been enhanced by canonical Wnt reporter mice, TOPGAL, BATGAL and Axin2(LacZ). Although widely used, it remains unclear whether these reporters convey the same information about canonical Wnt signaling. We therefore compared beta-galactosidase expression patterns in canonical Wnt signaling of these reporter mice in whole embryo versus isolated prenatal lungs. To determine if expression varied further during repair, we analyzed comparative pulmonary expression of beta-galactosidase after naphthalene injury. Our data show important differences between reporter mice. While TOPGAL and BATGAL lines demonstrate Wnt signaling well in early lung epithelium, BATGAL expression is markedly reduced in late embryonic and adult lungs. By contrast, Axin2(LacZ) expression is sustained in embryonic lung mesenchyme as well as epithelium. Three days into repair after naphthalene, BATGAL expression is induced in bronchial epithelium as well as TOPGAL expression (already strongly expressed without injury). Axin2(LacZ) expression is increased in bronchial epithelium of injured lungs. Interestingly, both TOPGAL and Axin2(LacZ) are up regulated in parabronchial smooth muscle cells during repair. Therefore the optimal choice of Wnt reporter line depends on whether up- or down-regulation of canonical Wnt signal reporting in either lung epithelium or mesenchyme is being compared.     

Weeds ability to phytoremediate cadmium-contaminated soil

An alternative method to other technologies to clean up the soil, air and water pollution by heavy metals is phytoremediation. Therefore, a pot culture experiment was conducted at the College of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran, in 2014 to determine the potential absorption of cadmium by Portulaca oleracea (Common purslane), Solanum nigrum (Black nightshade), Abutilon theophrasti (Velvetleaf) and Taraxacum officinale (Dandelion). The type of experiment was completely randomized design with factorial arrangement and four replications. The soil in pot was treated with different rates of CdCl₂.H₂O (0 (control), 10, 20, 40, 60, and 80 mg Cd/kg soil) and the plants were sown. With increasing concentration levels, fresh weight and dry weight of shoots and roots of all plant species were reduced. The reduction severity was ranked according the following order, P. oleracea > A. theophrasti > S. nigrum > T. officinale. Bioconcentration factor (BCF), Translocation factor (TF) and Translocation efficiency (TE%) was ranked according the following order, T. officinale > S. nigrum > A. theophrasti > P. oleracea. The results of this study revealed that T. officinale and S. nigrum are effective species to phytoremediate Cd-contaminated soil.     

Amplification and activation of c-Ki-ras oncogene in cell line developed from human pancreas explants.

Amplification and activation of c-Ki-ras gene was studied in normal human pancreas and a cell line (T-3) derived from normal pancreas explants exposed to methylnitrosourea (MNU) for 26 weeks. Normal genomic DNAs from pancreas and derived cell lines showed no transforming activity in NIH 3T3 cells. However, DNAs isolated from tumorigenic cell line derived from MNU treated human pancreas explants transformed NIH 3T3 cells. The hybridization profiles showed that the c-Ki-ras gene was amplified 5 fold in the tumorigenic cells (T-3). The level of mRNA specific to the c-Ki-ras gene was found to be 50-60 fold higher in the malignant cells than in normal human pancreas. These results suggest that higher expression of ras genes is due to gene amplification and/or activation, which is an important step in carcinogenesis.     

Discovery of novel 1,4-dihydropyridine-based PDE4 inhibitors

Substituted 1,4-dihydropyridines were discovered as a novel and potent series of phosphodiesterase 4 (PDE4) inhibitors. Structure–activity relationships within this series have been carried out and studies revealed that the dihydropyridine core, with indole moiety and 3,4-dimethoxybenzyl group, is a potent analogue for PDE4 inhibition. These novel series of compounds were prepared via a 3-component reaction in a single pot. In vitro biological activity, modeling studies and crystallography data are also reported.