Adenoviral short hairpin RNA therapy targeting phosphodiesterase 5a relieves cardiac remodeling and dysfunction following myocardial infarction

We previously showed that treatment with tadalafil, a long-acting phosphodiesterase-5a (PDE5a) inhibitor, effectively prevented adverse left ventricular (LV) remodeling of the infarcted heart. We hypothesized that short-hairpin RNA (shRNA) therapy targeting PDE5a would simulate the effects of pharmacological intervention for treatment of postinfarction LV remodeling and dysfunction. Experimental model of myocardial infarction was developed in female mice by permanent ligation of left coronary artery. Immediately after that, an adenoviral vector encoding for shRNA sequence targeting PDE5a (Ad-shPDE5a) was injected intramyocardially, which specifically inhibited PDE5a in the heart. Four weeks later, Ad-shPDE5a treated mice showed significant mitigation of the left ventricle (LV) dilatation and dysfunction as indicated by smaller LV cavity and more preserved ejection fraction and fractional shortening. Infarction size and fibrosis were significantly reduced in Ad-shPDE5a-treated mice. Additionally, more salvaged cardiomyocytes, significantly reduced collagen contents, and higher blood vessel density were observed in Ad-shPDE5a-treated mice. The cytoprotective effects of Ad-shPDE5a were demonstrated in vitro in Ad-shPDE5a transfected cardiomyocytes cultured under oxygen glucose deprivation. Among downstream mediators of PDE5a signaling, cyclic GMP (cGMP) and cGMP-dependent protein kinase G (PKG) were activated with concomitant reduction in caspase-3 activity. However, no significant change in PKA and cAMP activities were observed in Ad-shPDE5a-treated hearts. Inhibition with shRNA improved cardiac remodeling and dysfunction by reducing infarction size and cardiac fibrosis and increased cGMP and PKG activity. These findings suggest that PDE5 inhibition with Ad-shPDE5a is a novel approach for treatment of myocardial infarction.     

Molecular heterogeneity in the 18s DNA gene of Alternaria sp. and Fusarium sp. producing mycotoxins in rice and maize grains

Background

Food contaminated with fungi and their toxins is a problem that threatens many developing countries. Kingdom of Saudi Arabia depends on the exported grain and legume seeds.

A Probable Risk Factor of Female Breast Cancer: Study on Benign and Malignant Breast Tissue Samples

The study reports enhanced Fe, Cu, and Zn contents in breast tissues, a probable risk factor of breast cancer in females. Forty-one formalin-fixed breast tissues were analyzed using atomic absorption spectrophotometry. Twenty malignant, six adjacent to malignant and 15 benign tissues samples were investigated. The malignant tissues samples were of grade 11 and type invasive ductal carcinoma. The quantitative comparison between the elemental levels measured in the two types of specimen (benign and malignant) tissues (removed after surgery) suggests significant elevation of these metals (Fe, Cu, and Zn) in the malignant tissue. The specimens were collected just after mastectomy of women aged 19 to 59 years from the hospitals of Islamabad and Rawalpindi, Pakistan. Most of the patients belong to urban areas of Pakistan. Findings of study depict that these elements have a promising role in the initiation and development of carcinoma as consistent pattern of elevation for Fe, Cu, and Zn was observed. The results showed the excessive accumulation of Fe (229?±?121 mg/L) in malignant breast tissue samples of patients (p?<?0.05) to that in benign tissues samples (49.1?±?11.4 mg/L). Findings indicated that excess accumulation of iron in malignant tissues can be a risk factor of breast cancer. In order to validate our method of analysis, certified reference material muscle tissue lyophilized (IAEA) MA-M-2/TM was analyzed for metal studied. Determined concentrations were quite in good agreement with certified levels. Asymmetric concentration distribution for Fe, Cu, and Zn was observed in both malignant and benign tissue samples.     

GUSP1 and GUSP2, Two Drought-Responsive Genes in Gossypium arboreum Have Homology to Universal Stress Proteins

Two closely related genes GUSP1 and GUSP2, within the universal stress protein (USP) family, were identified and cloned from water-stressed leaves of Gossypium arboreum. GUSP1 and GUSP2 genes code for proteins with predicted molecular weights of 18.2 and 19.1 kDa, respectively. Sequence analysis showed that GUSP1 and GUSP2 are highly similar to the bacterial MJ0577-type of adenosine-triphosphate-binding Usp proteins, which have been proposed to function as a molecular switch. Nucleotide sequences of these two genes showed 81% sequence similarity while their encoded proteins share 75% amino acid homology. Both proteins have high percentages of similarity (17% to 61%) to the USPs from a variety of bacteria and plants. Real-time polymerase chain reaction expression analysis revealed a high level of GUSP gene expression in leaves, roots, and stems exclusively in plants following water stress. The highest levels of drought-inducible expression were found in the leaves. A progressive decrease in expression was observed in the stem and roots compared to very low expression in control tissues.     

Mini-scale Genomic DNA Extraction from Cotton

Large amounts of polyphenolics in cotton leaves make it difficult to obtain high-quality genomic DNA during extraction. A procedure to isolate nuclear DNA from local cotton leaves (gossypium hirsutum, MNH93, CIM443, FH672) was therefore developed. It consists of rapid isolation of stable nuclei, which hinders covalent interactions with phenolics, followed by DNA extraction. The yield and quality of the resulting DNA is satisfactory and the protocol can be scaled up or down according to sample size. It is suitable for PCR and the restriction enzyme digestion needed for Southern and RFLP analysis.     

Strain and cultivar specificity in the Agrobacterium-chickpea interaction

The susceptibility of four genotypes of chickpea to four wild strains of Agrobacterium tumefaciens was evaluated. Successful transformation was dependent on specific bacterial strain-plant cultivar interactions. Agropine strain A281 was the most effective for tumor induction. Tumors displayed hormone autonomous growth, were opine positive and contained DNA that was homologous to the T-DNA of the inciting strain.