Glucose metabolism of embryos and endosperms from deteriorating barley and wheat seeds

Changes in glucose utilization into CO₂ and ethanol-insoluble material were followed in whole seeds, embryos, and endosperms of wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) which had reached different levels of deterioration through accelerated aging treatments. Excised embryos from deteriorated wheat seeds had reduced respiration and glucose utilization into ethanol-insoluble material but not into CO₂. These treatments had no effect on respiration of excised endosperms, although they reduced utilization of glucose into ethanol-insoluble material and CO₂. Changes in metabolic activity of whole seeds in response to deterioration treatments are difficult to interpret because they represent the sum of the changes that take place in the embryos and endosperms. Changes in respiration and glucose utilization in these two tissues neither proceed at the same rate nor go in the same direction during deterioration.     

Metabolism of barley seed during early hours of germination

The growth process in germinating barley seeds and its inhibition by actinomycin D and puromycin were investigated. Soon after seeds are imbided, their respiratory activity increases several fold, and the protein- and carbohydrate-synthesizing systems become active. The immediate activation of protein synthesis and its inhibition by actinomycin D and puromycin suggest that the dry seed has all the components necessary for protein synthesis.     

MicroRNA signature in hepatocellular carcinoma patients: identification of potential markers

MicroRNAs (miRNAs) play important roles in liver pathologies and they are potential biomarkers for diagnosis of liver diseases progression. Changes in miRNA sera expression can be used as non-invasive biomarkers for hepatocellular carcinoma (HCC). The aim of the study was to identify the miRNome profiling of HCC and its diagnostic value in distinguishing HCC from healthy individuals. Expression profiles of miRNAs in serum samples of 20 HCC patients and 10 healthy controls were detected. Whole miRNome profiling was done using next generation sequencing. Receiver operating characteristic (ROC) analysis was performed to assess the diagnostic performance of the deregulated miRNAs for discriminating HCC cases from healthy controls. MiRNA 142 was highly expressed in HCC (P value?=?0.023) while miRNAs 191, 22, and 126 were higher in the controls (P value?=?0.005, 0.034, 0.010 respectively). We have identified 5 novel miRNAs and they were highly expressed in HCC than controls. Analysis of ROC curve demonstrated that these deregulated miRNAs can be used as a reliable biomarker for detection of HCC with high diagnostic accuracy (AUC?=?0.93). We have detected a panel of serum miRNAs that can be used as a reliable noninvasive screening biomarker of HCC. The study recommends further research to shed light on a possible role of the newly discovered novel miRNAs in HCC pathogenesis.

     

DNA uptake during electroporation of germinating pollen grains

Electroporation of germinating pollen grains of Nicotiana gossei (L.) Domin under a variety of conditions showed that DNA was taken up by the pollen without detrimental effects on the viability of the pollen. By optimizing both the field strength of the electroporation pulse and the DNA concentration in the electroporation medium up to 6% of the donor DNA can be taken up by the germinating pollen while maintaining a pollen viability of 90%. Field strengths as high as 9 kV/cm could be applied to germinating pollen grains without detrimental effects on viability. Southern hybridizations demonstrated that DNA encoding the marker enzyme β-glucuronidase (GUS) was incorporated into electroporated pollen. Germinating pollen, treated in this manner, is capable of producing 300–400 seeds per capsule of viable seed when applied to the stigmas of compatible flowers of N. gossei which has been emasculated 4 days earlier.     

Efficacy and safety of rabeprazole, amoxicillin, and gatifloxacin after treatment failure of initial Helicobacter pylori eradication

OBJECTIVES: To evaluate the efficacy of a 7-day regimen of gatifloxacin (400 mg daily), amoxicillin (1 g twice a day), and rabeprazole (20 mg twice a day) in the secondary eradication of Helicobacter pylori infection. METHODS: Eligible patients with persistent infection following one or more conventional clarithromycin-containing triple therapies were enrolled in this open-label trial. Eradication of infection was documented by (14)C-urea breath test a minimum of 4 weeks after therapy and 2 weeks off any acid suppressive therapy. Culture of H. pylori and in vitro susceptibility testing to amoxicillin, clarithromycin, and gatifloxacin was done in cases of failed eradication. RESULTS: A total of 45 patients (22 females:23 males; mean age 44.5 +/- 13 years) were enrolled. Eradication occurred in 38 patients [both per-protocol (PP) and intention-to-treat analysis: 84.4%; 95% CI: 74-95%]. No significant adverse effects were reported. In vitro susceptibility testing showed no secondary resistance to gatifloxacin or amoxicillin in any of the seven nonresponders. Smoking, age, and sex were not predictors of potential eradication failure. CONCLUSIONS: A 7-day regimen of gatifloxacin, rabeprazole, and amoxicillin is effective after failed eradication therapy for H. pylori and does not appear to result in secondary resistance. This combination is simple, well tolerated, and may lead to higher compliance and lower costs.     

Separation of poly(A) RNA's synthesized by soybean embryos

A stepwise elution procedure in which the MAK column with 0.85M buffered NaCl is held in a stationary phase (2–3 psi,35?C, 1 hr) permits the separation of two tenaciously boundRNA fractions. Poly(A) RNA's elute with the ribosomal and tenaciouslybound RNA's. MAK fractions contain different percent of RNA'sthat bind to poly(dT) cellulose and have messenger RNA activity.The results suggest that the soybean embryonic tissue synthesized,at least, four poly(A) RNA's. (Received August 17, 1976; )     

Regulation by auxin of carbohydrate metabolism involved in cell wall synthesis by pea stem tissue

Promotion of cell wall synthesis (from glucose) in pea (Pisum sativum) stem segments by indoleacetic acid (IAA) develops over a period of 1 to 2 hours and is comprised of a promotion of glucose uptake plus a promotion of the utilization of absorbed glucose. The effect of IAA resembles, in these and other respects, its effect on cell wall synthesis in oat coleoptile segments, but the pea system differs in not being inhibited by galactose or mannose, in involving considerably more isotope dilution by endogenous substrates, and in certain other respects.     

Changes in Respiration and Cyanide Sensitivity of the Barley Floret during Development and Maturation

The 6-week period of development and maturation of the barley (Hordeum vulgare L.) floret from anthesis to harvest is characterized by two phases: an early phase of rapid increase in respiration rate and dry weight, and a late phase during which respiration decreased rapidly whereas dry weight remained unchanged. Consumption of O₂ by the embryo changed little during the entire developmental period, whereas O₂ uptake by the endosperm and the lemma and palea decreased significantly during the late phase.     

Expression of a foreign gene in electroporated pollen grains of tobacco

Summary The incorporation of genetically engineered DNA into pollen and subsequent fertilization of eggs by the transformed pollen would be a convenient method for producing genetically engineered seed. This method of pollen transformation would circumvent the need for other types of gene transfer methods such as the use of Agrobacterium tumefaciens, which has a limited host range and thus a limited capability for genetically engineering plants. It would also avoid the problems associated with the regeneration of some plants from tissue, cell, or protoplast culture after receiving foreign DNA. To this end, the genetically engineered plasmid DNA vector pBI221 containing the gene encoding -glucuronidase (GUS) was introduced by electroporation into germinating pollen grains of tobacco (Nicotiana gossei L.). Transient expression of the GUS gene was demonstrated by the presence of GUS activity in fluorometric assays of pollen extracts 24 h after the introduction of pBI221 via electroporation. Intact pBI221 was detected by Southern blotting procedures as a distinct DNA band in pollen extracts 1 h after electroporation. In addition, pBI221 was detected as a diffuse band of higher molecular weight DNA 24 h after electroporation, suggesting that some of the pBI221 was incorporated into the genome of the pollen.