Over-Expression of an Arabidopsis Zinc Transporter in Hordeum Vulgare Increases Short-Term Zinc Uptake after Zinc Deprivation and Seed Zinc Content

Increasing the zinc content of cereal grains will be important for improving human nutrition. Improved plant zinc efficiency will lead to increased yields when available zinc is limiting plant growth. The aim of our work was to test how the over-expression of zinc transporters in cereals affects plant growth, seed mineral content, and zinc transport rates. Known zinc transporters from Arabidopsis were over-expressed in Hordeum vulgare cv. Golden Promise by means of a ubiquitin promoter. Multiple transgenic lines were obtained, and the locus number and expression levels were verified. Transgenic lines were tested in long-term growth and short-term uptake experiments. Seeds from transgenic lines grown in soil had higher zinc and iron contents than controls. Short-term uptake rates were higher in the transgenic lines after zinc deprivation. Resupply of zinc after a period of deprivation resulted in the rapid decrease in zinc uptake even in transgenic lines in which a zinc transporter gene was constitutively expressed. Similar to processes in yeast and Arabidopsis, we hypothesize that this rapid decrease in zinc transport activity may be caused by the degradation of transporters in response to zinc-sufficient conditions. In the long-term growth experiments, there were no significant differences between transgenic and control lines in leaf zinc content or shoot biomass under zinc-sufficient or -deficient conditions. However, root-to-shoot ratios were higher in the transgenic plants grown under low-zinc conditions; this could impact zinc acquisition under field conditions. Increased seed zinc and iron content by over-expression of a zinc transporter provides a new strategy for increasing the micronutrient content of cereals.     

Basic fibroblast growth factor increases collateral blood flow in spontaneously hypertensive rats

Ischemia-induced angiogenic response is reduced in spontaneously hypertensive rats (SHR). To study whether exogenous basic fibroblast growth factor (bFGF) infusion is effective in expanding collateral circulation in frankly hypertensive SHR, femoral arteries of male SHR (weighing approximately 250 g) were kept intact (nonoccluded control; n = 9) or occluded for 4h(n = 12) or for 16 days with vehicle (n = 14) or bFGF [0.5 (n = 17), 5.0 (n = 13), and 50.0 (n = 14) microg. kg-1. day-1 for 14 days] intraarterially. Maximal collateral-dependent blood flows (BF) to the hindlimbs were determined with 85Sr- and 141Ce-labeled microspheres during running at 20 and 25 m/min (15% grade). Preexercise heart rates (approximately 530 beats/min) and blood pressures (BP; approximately 200 mmHg) were similar across groups except in the high-dose bFGF group, where BP was reduced by approximately 12% (P < 0.05). Femoral artery occlusion for 4 h resulted in approximately 95% reduction of BF in calf muscles [199 +/- 18.7 (nonoccluded group) to 10 +/- 1.0 ml. min-1. 100 g-1; P < 0.001]. BF to calf muscles of the vehicle and low-dose bFGF (0.5 microg. kg-1. day-1) groups increased to 36 +/- 3.2 and 45 +/- 2.0 ml. min-1. 100 g-1, respectively (P < 0.001). bFGF infusion at 5.0 and 50.0 microg. kg-1. day-1 further increased (P < 0.001) BF to calf muscles (62 +/- 4.6 and 62 +/- 2.2 ml. min-1. 100 g-1, respectively). Our results show that bFGF can effectively increase BF in hypertensive rats. The reduced hypertension with high-dose bFGF suggests that a critical signal in arteriogenesis (nitric oxide bioavailability) may be restored. These findings suggest that the dulled endothelial nitric oxide synthase of SHR does not preempt collateral vessel remodeling.     

Metastatic sweat gland adenocarcinoma: A clinico-pathological dilemma

Background  

Sweat gland adenocarcinoma is a rare malignancy with high metastatic potential seen more commonly in later years of life. Scalp is the most common site of occurrence and it usually spreads to lymph nodes. Liver, lung and bones are the distant sites of metastasis with fatal results. The differentiation between apocrine and eccrine metastatic sweat gland carcinoma is often difficult. The criteria's are inadequate to be of any practical utility.     

Positive correlation between menthol content andin vitro menthol tolerance inMentha arvensis L. cultivars

Menthol is a highly valued monoterpene produced by Japanese mint (Mentha arvensis) as a natural product with wide applications in cosmetics, confectionery, flavours, beverages and therapeutics. Selection of high menthol yielding genotypes is therefore the ultimate objective of all genetic improvement programmes inMentha arvensis. A positive correlation was observed in the present study between menthol content in oils of evaluated genotypes and the level of tolerance to externally supplied menthol of explants of these genotypes in culture medium. The easy use of this relationship as a selectable biochemical marker opens the practical applicability of largescalein vitro screening of the germplasm, clones and breeders' material for selection of elite genotypes.     

High regenerative nature ofMentha arvensis internodes

Media and incubation conditions have been defined for highly efficient regeneration of shoots from internode explants of slow and fast growing cultivars ofMentha arvensis. Internodal segments excised from thein vitro raised shoots were inoculated on the MS medium supplemented with combinations of 5 concentrations of l-napthalene acetic acid (NAA) and 3 concentrations of 6-benzyl amino purine (BAP). The media containing 2 μg ml⁻¹ NAA, 10 Μg ml⁻¹ BAP and 1 μg ml⁻¹ NAA, 5 μg ml⁻¹ BAP proved best for shoot regeneration and growth responses on cv Himalaya and cv Kalka explants, respectively. In 12 weeks time, on average one explant of cv Himalaya produced about 200 shoots and that of cv Kalka produced about 180 shoots. The Himalaya explants required higher concentrations of NAA and BAP for high efficiency proliferation as compared to the Kalka explants. The experiments demonstrated that internodal tissue inMentha arvensis can be induced to obtain direct shoot regenerants with high efficiency. The analysis of the RAPD profiles of 100 regenerated plantlets each of cv Himalaya and Kalka showed more than 99.9% homogeneity in bands with respect to the parents.     

Diarrhea,Stimulation and Growth Predict Neurodevelopment in Young North Indian Children

Background and Objective

Infants and young children in low to middle-income countries are at risk for adverse neurodevelopment due to multiple risk factors. In this study, we sought to identify stimulation and learning opportunities, growth, and burden of respiratory infections and diarrhea as predictors for neurodevelopment.

Methods

We visited 422 North Indian children 6 to 30 months old weekly for six months. Childhood illnesses were assessed biweekly. At end study, we assessed neurodevelopment using the Ages and Stages Questionnaire 3^rd ed. (ASQ-3) and gathered information on stimulation and learning opportunities. We identified predictors for ASQ-3 scores in multiple linear and logistic regression models.

Results

We were able to explain 30.5% of the variation in the total ASQ-3 score by the identified predictors. When adjusting for child characteristics and annual family income, stimulation and learning opportunities explained most of the variation by 25.1%. Height for age (standardized beta: 0.12, p<.05) and weight for height z-scores (std. beta: 0.09, p<.05) were positively associated with the total ASQ-3 score, while number of days with diarrhea was negatively associated with these scores (std. beta: -0.13, p<0.01).

Conclusion

Our results support the importance of early child stimulation and general nutrition for child development. Our study also suggests that diarrhea is an additional risk factor for adverse neurodevelopment in vulnerable children.     

Pyrethroid-Resistance and Presence of Two Knockdown Resistance (kdr) Mutations,F1534C and a Novel Mutation T1520I,in Indian Aedes aegypti

Background

Control of Aedes aegypti, the mosquito vector of dengue, chikungunya and yellow fever, is a challenging task. Pyrethroid insecticides have emerged as a preferred choice for vector control but are threatened by the emergence of resistance. The present study reports a focus of pyrethroid resistance and presence of two kdr mutations—F1534C and a novel mutation T1520I, in Ae. aegypti from Delhi, India.

Methodology/Principal Findings

Insecticide susceptibility status of adult-female Ae. aegypti against DDT (4%), deltamethrin (0.05%) and permethrin (0.75%) was determined using WHO''s standard insecticide susceptibility kit, which revealed resistance to DDT, deltamethrin and permethrin with corrected mortalities of 35%, 72% and 76% respectively. Mosquitoes were screened for the presence of kdr mutations including those reported earlier (I1011V/M, V1016G/I, F1534C, D1794Y and S989P), which revealed the presence of F1534C and a novel mutation T1520I. Highly specific PCR-RFLP assays were developed for genotyping of these two mutations. Genotyping using allele specific PCR and new PCR-RFLP assays revealed a high frequency of F1534C (0.41–0.79) and low frequency of novel mutation T1520I (0.13). The latter was observed to be tightly linked with F1534C and possibly serve as a compensatory mutation. A positive association of F1534C mutation with DDT and deltamethrin resistance in Ae. aegypti was established. However, F1534C-kdr did not show significant protection against permethrin.

Conclusions/Significance

The Aedes aegypti population of Delhi is resistant to DDT, deltamethrin and permethrin. Two kdr mutations, F1534C and a novel mutation T1520I, were identified in this population. This is the first report of kdr mutations being present in the Indian Ae. aegypti population. Highly specific PCR-RFLP assays were developed for discrimination of alleles at both kdr loci. A positive association of F1534C mutation with DDT and deltamethrin resistance was confirmed.     

Bishydrazide glycoconjugates for lectin recognition and capture of bacterial pathogens

Bishydrazides are versatile linkers for attaching glycans to substrates for lectin binding and pathogen detection schemes. The α,ω-bishydrazides of carboxymethylated hexa(ethylene glycol) (4) can be conjugated at one end to unprotected oligosaccharides, then attached onto carrier proteins, tethered onto activated carboxyl-terminated surfaces, or functionalized with a photoactive cross-linking agent for lithographic patterning. Glycoconjugates of bishydrazide 4 can also be converted into dithiocarbamates (DTCs) by treatment with CS(2) under mild conditions, for attachment onto gold substrates. The immobilized glycans serve as recognition elements for cell-surface lectins and enable the detection and capture of bacterial pathogens such as Pseudomonas aeruginosa by their adsorption onto micropatterned substrates. A detection limit of 103 cfu/mL is demonstrated, using a recently introduced method based on optical pattern recognition.     

Establishment of <Emphasis Type="Italic">lacZ</Emphasis> marked strain of phosphate solubilizing bacterium in the rhizosphere and its effect on plant growth in mungbean

The establishment of lacZ marked strain of P-solubilizing bacterium Pseudomonas in the rhizosphere of mungbean (Vigna radiata) under pothouse conditions was studied. The lacZ marker was transferred to Pseudomonas P-36 on LB medium using donor strain of E. coli. The lacZ marked strain formed blue colonies on selective media and could be identified from soil on the basis of this character. The lacZ marked strain was able to survive in rhizosphere of mungbean under pothouse conditions and maintained a population of about 10⁴ g^?1 of rhizosphere soils up to 60 days study period. Positive effect of inoculation with P-solubilizing bacterium on dry matter yield, P and N-uptake was observed using rock phosphate and single super phosphate as P sources with and without farmyard amendment.