Responses of some selected Malaysian rice genotypes to callus induction under in vitro salt stress

Tissue culture technique can be used as a source for genetic variability by means of genetic modifications through the process of in vitro cultures. This technique has been widely used for breeding purposes, especially for stress tolerance selection, which severely limits rice production. Also, the establishment of a suitable plant regeneration system is a prerequisite for successful genetic transformation. The aim of this study is to identify the most suitable medium and to assess the genotype performance for in vitro salt stress responses in some selected Malaysian rice genotypes. Differences in culture conditions, growth rate, plant hormone responses and accumulation of proline content were monitored. All the selected genotypes showed that the callus-growth capacities were significantly affected by the genotypes and the culture media. Evidently, callus was best induced on the MS medium added with 10 ìM dichlorophenoxyacetic acid (2,4-D) and 0.4 gm/l casein hydrolysate. In addition, the shoot regeneration capacity from the callus was the most effective in ½ MS added with 10 ìM 6 benzylaminopurine (BAP). The two genotypes, that is, MR219 (line 4) and MR219 (line 9), consistently performed the best in both callus culture (93.51 and 92.22%) and plant regeneration capacity (27.03 and 26.34%), respectively. When the callus were transferred to different concentrations of NaCl (0 to 250 mM) supplemented medium in order to examine their responses to salinity, the two genotypes, that is, MR219 (line 4) and MR219 (line 9), showed a significant decline in the callus growth (18.83 and 23.5%) and regeneration capacity (7.33 and 7.68%), respectively. A similar trend was also observed for the proline content. All the genotypes significantly resulted in proline accumulation.MR211 showed the highest accumulation, whereas MR219 (line 4) revealed the lowest proline accumulation. These proline content analyses further suggest potential salinity tolerance in the rice genotypes.Key words: Plant regeneration, embryogenesis, salinity, callus

Albumin: Creatinine Ratio during long term Diabetes Mellitus in the Assessment of early Nephropathy in Sudanese Population

Background: Diabetic nephropathy is one of the major causes of chronic renal failure. Microalbuminuria (MAU) has been recognized as an independent and reliable predictor for future development of overt proteinuria in diabetic patients.Objectives: This descriptive cross-sectional study was carried during the period of January-April 2012, in Omdurman Teaching Hospital, to determine Microalbuminuria creatinine ratio, in long term Diabetic patients.Materials and Methods: Immunoturbidmetric method was used to asses’ microalbuminuria in 50 cases (50%) and 50 controls (50%). Ordinary chemical method (Jaffe reaction) was used for the determination of creatinine for both the groups.Results: Microalbuminuria in Diabetic patients showed an increase when compared with the control group with P value 0.000. Similarly creatinine also showed an increase in diabetic patients.Conclusion: It was concluded and is in further affirmation of the previous studies that microalbuminuria should be used as an early indicator for Diabetic Nephropathy. Further studies with 24 hour urine sample are recommended for assessment of Microalbuminuria in long term Diabetic patients, provided that the patients are on a normal diet with regular treatment for diabetes.Key words: Microalbuminuria, Creatinine, Diabetes mellitus, Nephropathy

Biochemical Parameters in Relation to Tuberculosis in Sudanese Patients

Background: Malnutrition and wasting are associated with TB and HIV infection. Malnutrition and tuberculosis are both problems of considerable magnitude in most of the underdeveloped regions of the world. Nutritional status is significantly lower in patients with active tuberculosis compared with healthy controls. Both, protein-energy malnutrition and micronutrients deficiencies increase the risk of tuberculosis.Objectives: To investigate the concentration of serum albumin, total protein, glutamate oxalo acetate transaminase (GOT), glutamate pyruvate transaminase (GPT) and zinc in Sudanese tuberculosis patients (TB), attending the Tropical Diseases Teaching Hospital, Khartoum State.Materials and Methods: The study was performed on 60 tuberculosis patients, compared with 40 healthy individual age and sex matched used as control group .The study period was from April to August 2011. Serum albumin, total protein, GOT and GPT levels were determined by using clinical chemistry analyzer while zinc level was analyzed by atomic absorption spectro-photometers.Results: Among TB patients the mean ±SD of plasma albumin, total protein, GOT, GPT and zinc respectively were 3.29±0.91, 7.55±1.59, 21.24±8.33, 9.12±6.34 and 0.47±0.17. The mean ±SD of plasma albumin, total protein, GOT, GPT and zinc for control group respectively were 4.19±0.93, 8.0±0.98, 26.0±9.08, 13.3±8.15, and 0.55±0.14. Statistically significant association was observed in all parameters between the patients and control group (P<0.05).Conclusions: This study concluded that TB patients had significant decreased levels of all parameters; however albumin and GPT were more significant as compared to others.Keywords: Tuberculosis, Total protein, Albumin, Liver enzymes, Zinc

Optimizing the lateral beamforming step for filtered-delay multiply and sum beamforming to improve active contour segmentation using ultrafast ultrasound imaging

As an alternative to delay-and-sum beamforming, a novel beamforming technique called filtered-delay multiply and sum (FDMAS) was introduced recently to improve ultrasound B-mode image quality. Although a considerable amount of work has been performed to evaluate FDMAS performance, no study has yet focused on the beamforming step size, , in the lateral direction. Accordingly, the performance of FDMAS was evaluated in this study by fine-tuning to find its optimal value and improve boundary definition when balloon snake active contour (BSAC) segmentation was applied to a B-mode image in ultrafast imaging. To demonstrate the effect of altering in the lateral direction on FDMAS, measurements were performed on point targets, a tissue-mimicking phantom and in vivo carotid artery, by using the ultrasound array research platform II equipped with one 128-element linear array transducer, which was excited by 2-cycle sinusoidal signals. With 9-angle compounding, results showed that the lateral resolution (LR) of the point target was improved by 67.9% and 81.2%, when measured at −6 dB and −20 dB respectively, when was reduced from to . Meanwhile the image contrast ratio (CR) measured on the CIRS phantom was improved by 10.38 dB at the same reduction and the same number of compounding angles. The enhanced FDMAS results with lower side lobes and less clutter noise in the anechoic regions provides a means to improve boundary definition on a B-mode image when BSAC segmentation is applied

Increased sensitivity to gemcitabine of P-glycoprotein and multidrug resistance-associated protein-overexpressing human cancer cell lines

0.05), respectively. P-glycoprotein and MRP1 overexpression possibly caused a cellular stress resulting in increased gemcitabine metabolism and sensitivity, while reversal of collateral gemcitabine sensitivity by verapamil also suggests a direct relation between the presence of membrane efflux pumps and gemcitabine sensitivity

18S rDNA Phylogeny of Lamproderma and Allied Genera (Stemonitales, Myxomycetes, Amoebozoa)

The phylogenetic position of the slime-mould genus Lamproderma (Myxomycetes, Amoebozoa) challenges traditional taxonomy: although it displays the typical characters of the order Stemonitales, it appears to be sister to Physarales. This study provides a small subunit (18S or SSU) ribosomal RNA gene-based phylogeny of Lamproderma and its allies, with new sequences from 49 specimens in 12 genera. We found that the order Stemonitales and Lamproderma were both ancestral to Physarales and that Lamproderma constitutes several clades intermingled with species of Diacheopsis, Colloderma and Elaeomyxa. We suggest that these genera may have evolved from Lamproderma by multiple losses of fruiting body stalks and that many taxonomic revisions are needed. We found such high genetic diversity within three Lamproderma species that they probably consist of clusters of sibling species. We discuss the contrasts between genetic and morphological divergence and implications for the morphospecies concept, highlighting the phylogenetically most reliable morphological characters and pointing to others that have been overestimated. In addition, we showed that the first part (∼600 bases) of the SSU rDNA gene is a valuable tool for phylogeny in Myxomycetes, since it displayed sufficient variability to distinguish closely related taxa and never failed to cluster together specimens considered of the same species

Epistasis for Growth Rate and Total Metabolic Flux in Yeast

Studies of interactions between gene deletions repeatedly show that the effect of epistasis on the growth of yeast cells is roughly null or barely positive. These observations relate generally to the pace of growth, its costs in terms of required metabolites and energy are unknown. We measured the maximum rate at which yeast cultures grow and amounts of glucose they consume per synthesized biomass for strains with none, single, or double gene deletions. Because all strains were maintained under a fermentative mode of growth and thus shared a common pattern of metabolic processes, we used the rate of glucose uptake as a proxy for the total flux of metabolites and energy. In the tested sample, the double deletions showed null or slightly positive epistasis both for the mean growth and mean flux. This concordance is explained by the fact that average efficiency of converting glucose into biomass was nearly constant, that is, it did not change with the strength of growth effect. Individual changes in the efficiency caused by gene deletions did have a genetic basis as they were consistent over several environments and transmitted between single and double deletion strains indicating that the efficiency of growth, although independent of its rate, was appreciably heritable. Together, our results suggest that data on the rate of growth can be used as a proxy for the rate of total metabolism when the goal is to find strong individual interactions or estimate the mean epistatic effect. However, it may be necessary to assay both growth and flux in order to detect smaller individual effects of epistasis

Gender Differences in S-Nitrosoglutathione Reductase Activity in the Lung

S-nitrosothiols have been implicated in the etiology of various pulmonary diseases. Many of these diseases display gender preferences in presentation or altered severity that occurs with puberty, the mechanism by which is unknown. Estrogen has been shown to influence the expression and activity of endothelial nitric oxide synthase (eNOS) which is associated with increased S-nitrosothiol production. The effects of gender hormones on the expression and activity of the de-nitrosylating enzyme S-nitrosoglutathione reductase (GSNO-R) are undefined. This report evaluates the effects of gender hormones on the activity and expression of GSNO-R and its relationship to N-acetyl cysteine (NAC)-induced pulmonary hypertension (PH). GSNO-R activity was elevated in lung homogenates from female compared to male mice. Increased activity was not due to changes in GSNO-R expression, but correlated with GSNO-R S-nitrosylation: females were greater than males. The ability of GSNO-R to be activated by S-nitrosylation was confirmed by: 1) the ability of S-nitrosoglutathione (GSNO) to increase the activity of GSNO-R in murine pulmonary endothelial cells and 2) reduced activity of GSNO-R in lung homogenates from eNOS−/− mice. Gender differences in GSNO-R activity appear to explain the difference in the ability of NAC to induce PH: female and castrated male animals are protected from NAC-induced PH. Castration results in elevated GSNO-R activity that is similar to that seen in female animals. The data suggest that GSNO-R activity is modulated by both estrogens and androgens in conjunction with hormonal regulation of eNOS to maintain S-nitrosothiol homeostasis. Moreover, disruption of this eNOS-GSNO-R axis contributes to the development of PH

5-Azacytidine Is Insufficient For Cardiogenesis In Human Adipose-Derived Stem Cells

<p>Abstract</p> <p>Background</p> <p>Adipose tissue is a source of multipotent adult stem cells and it has the ability to differentiate into several types of cell lineages such as neuron cells, osteogenic cells and adipogenic cells. Several reports have shown adipose-derived stem cells (ASCs) have the ability to undergo cardiomyogenesis. Studies have shown 5-azacytidine can successfully drive stem cells such as bone marrow derived stem cells to differentiate into cardiomyogenic cells. Therefore, in this study, we investigated the effect 5-azacytidine on the cardiogenic ability of ASCs.</p> <p>Methods</p> <p>The cardiogenic potential of ASCs was analysed by studying the morphological changes after induction, the changes in the cardiogenic genes expression i.e. GATA4, MLC-2v, MLC-2a, NKX2.5, β-MHC, α-MHC, Atrial natriuretic peptide (ANP), Connexin 43, Cardiac Troponin C, Cardiac Troponin I and myocyte enhancer factor (MEF2C) and the changes of embryonic stem cells genes expression at P5 and P10 using quantitative PCR.</p> <p>Results</p> <p>Our results showed that the induced ASCs did not show significant morphological difference compared to the non-induced ASCs. While quantitative PCR data indicated that most cardiogenic genes and stemness genes expression level decreased after induction at P5 and P10.</p> <p>Conclusion</p> <p>5-azacytidine is insufficient for the cardiogenic induction of the ASCs.</p