A Simple Method for Isolating DNA of High Yield and Quality from Cotton (shape Gossypium hirsutum L.) Leaves

An easy, reproducible and fast procedure to isolate DNA from cotton leaves is described. The addition of 0.5 M glucose in the extraction buffer avoids browning by polyphenolic compounds and improves the quality of DNA for molecular analysis. The DNA yield ranged between 150–400 mg per gram of fresh tissue. The DNA was suitable for digestion by restriction enzymes and amplificatiion by Taq DNA polymerase.     

The Golgi apparatus and lysosomes of rat pancreatic acinar cells following refeeding

Summary The short term effects of refeeding on the Golgi apparatus and lysosomes of the rat exocrine pancreas were evaluated by ultrastructural, morphometric and cytochemical methods. Ten minutes after refeeding, there was a significant enlargement of Golgi cisternae and a significant increase, compared with the controls, in the number of condensing vacuoles and lysosomes. These modifications were accompanied by the appearance of acid phosphatase activity in stacked Golgi cisternae (as well as GERL) of some cells. One hour after refeeding, there were about the same numbers of condensing vacuoles and lysosomes as in the control; Golgi cisternae were still significantly enlarged, compared with the controls, but they were no longer reactive for acid phosphatase. In both fasting and refed animals, acid phosphatase activity was demonstrable in tubular lysosomes.The data are interpreted in terms both of membrane disposal and recycling, leading to enhanced formation of zymogen granules, during physiologically stimulated secretion.     

Relationship between gene expression and hybrid vigor in primary root tips of young maize (Zea mays L.) plantlets

Summary To provide an insight into the molecular basis of heterosis, we investigated gene expression in primary root tips of a heterotic maize hybrid (B73 × Mo17) and its parental lines (B73 and Mo17). This analysis was carried out (i) by differential plaque hybridization of a recombinant cDNA library made to poly(A) RNA isolated from B73 × Mo17 primary root tips, and (ii) by comparing with two-dimensional gel electrophoresis proteins synthesized in vitro in the rabbit reticulocyte system by poly(A) RNA isolated, at different stages of development, from the three genotypes. The results showed that there are sets of proteins and mRNAs that are differentially synthesized and expressed in the F₁ primary root tips in comparison to the parental lines. Moreover, results from the survey of 21 major in-vitrosynthesized polypeptide variants, from mRNAs of primary root tips of the parental lines and their F₁ hybrid, indicated that in seven instances hybrid proteins translated in vitro were more abundant or possibly new. In most of the remaining cases, hybrid spots were similar in intensity to the same protein produced by one of the two parental lines.     

Effect of 17β-estradiol on calcium response to phytohaemagglutinin in human lymphocytes

Pre-treatment of human lymphocytes with 17-estradiol diminishes the increase in concentration of cytosolic free calcium after stimulation with phytohaemagglutinin. The effect is dependent on 17-estradiol concentration and on the preincubation time. The effect is not due to an interaction between 17-estradiol and phytohaemagglutinin, but appears to be a consequence of the binding of the hormone to the cell surface. The effect is specific for 17-estradiol, since the isomer and other steroid hormones (progesterone, testosterone, diethylstilbestrol and 5-androstan), have no effect. Since the effect of the 17-estradiol can be suppressed by treatment of lymphocytes with ouabain, it appears that the effect of estradiol on the rise of cytosolic calcium induced by phytohaemagglutinin is mediated by the (Na, K)-ATPase.     

A preliminary report on the use of transfer factor for treating stage D3 hormone-unresponsive metastatic prostate cancer

As conventional treatments are unsuccessful, the survival rate of stage D3 prostate cancer patients is poor. Reports have suggested the existence of humoral and cell-mediated immunity (CMI) against prostate cancer tumour-associated antigens (TAA). These observations prompted us to treat stage D3 prostate cancer patients with an in vitro produced transfer factor (TF) able to transfer, in vitro and in vivo, CMI against bladder and prostate TAA. Fifty patients entered this study and received one intramuscular injection of 2–5 units of specific TF monthly. Follow-up, ranging from 1 to 9 years, showed that complete remission was achieved in 2 patients, partial remission in 6, and no progression of metastatic disease in 14. The median survival was 126 weeks, higher than the survival rates reported in the literature for patients of the same stage.     

Physiologic target of the Air-1 trans-activator revealed by stable transfection assay

RJ 2.2.5 is a human B cell mutant, derived from Raji cells, which has lost expression of major histocompatibility complex (MHC) class II genes because of a defect in the AIR1 locus function. The MHC class II-positive phenotype can be restored by introducing an active AIR1 locus or its mouse equivalent, Air-1. An example of the latter is the H4 cell hybrid, derived by somatic cell fusion between RJ 2.2.5 and mouse class II-positive spleen cells. H4 contains a single mouse chromosome, autosome 16, in which the Air-1 locus maps, and an entire RJ 2.2.5-derived genome. In the present study we show that the physiologic target of the Air-1 locus product is contained within a limited HLA-DRA promoter sequence of 300 base pairs, encompassing the crucial Y, X, and W cis-acting elements. A plasmid construct, pDRA300neo, containing the HLA-DRA promoter sequence which drives the expression of the neomycin resistance gene, has been stably integrated in the genome of the H4 hybrid. Transfectants selected in the presence of G418 retain mouse chromosome 16 and express the DR genes. On the other hand, transfectants grown in a non-selective medium segregate mouse chromosome 16; this is accompanied by a loss of DRA gene expression and G418 resistance, although pDRA300neo is still integrated in the genome. These results offer scope for using this experimental model to clone the Air-1 gene in a straightforward way. Correspondence to: R. S. Accolla.     

A method of preparing woven Dacron aortic grafts to prevent interstitial hemorrhage

Severe and even fatal hemorrhage may be caused by bleeding through the interstices of a fabric graft. Improved fabrication of grafts with appropriate porosity for the conditions encountered has provided better hemostasis. Yet in some situations, bleeding through the fabric still presents a problem. A method of preclotting with autologous platelet rich plasma (PRP) and autoclaving is described. Gross and microscopic studies along with clinical applications confirm the effectiveness of the technique.