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The authors report on an energy transfer based fluorometric approach for the detection of nitroaromatic pollutants. This is achieved using 4-mercaptobenzoic acid (4-MBA)-capped CaF 2 :Tb 3+ nanocrystals that were synthesized by a microwave procedure. 4-MBA acts as both a capping agent and a sensitizer for the Tb 3+ ions in CaF 2 host matrix. This approach is different from the earlier studies where Ce 3+ is generally used as the sensitizer for the Ln 3+ ions. The use of capping ligand as sensitizer has the feature that binding of nitroaromatics directly to the sensitizer can alter the energy transfer efficiency between the sensitizer and the Tb 3+ ions. The fluorescent nanocrystal probe doped with 2% of Tb 3+ displays green emission with a peak at 542 nm if photoexcited at 311 nm. The emission is quenched if the nanocrystals are exposed to nitroaromatic compounds such as 4-nitrophenol, 2,4-dinitrophenol, 2,4,6-trinitrophenol (picric acid), 4-nitrotoluene, 2,4-dinitrotoluene and 2,4,6-trinitrotoluene. These analytes also cause a (longwave/shortwave) shift in the excitation maxima which helps in identifying the individual nitroaromatic compound using single nanoprobe. The respective detection limits (by applying the 3σ/K criterion) are 0.86 μM, 0.83 μM, 0.78 μM, 0.36 μM, 1.5 μM, and 1.96 μM. Graphical abstract Schematic illustration of the use of 4-mercaptobenzoic acid (MBA)-capped CaF 2 :Tb 3+ nanocrystals as a fluorescent nanoprobe for the detection of nitroaromatic analytes. The Tb 3+ ions show strong green fluorescence via 4-MBA-induced ligand sensitization. The specific π interaction between 4-MBA capped CaF 2 nanocrystals and nitroaromatics leads to reduction in the fluorescence intensity by inhibiting the energy transfer from 4-MBA to Tb 3+ ion in CaF 2 nanocrystals.

Aim: The present study was aimed to analyze the chromosomal changes obtained by using FISH. Fluorescence in situ hybridization (FISH) is a powerful technique used in the detection of chromosomal abnormalities., Materials and Methods: During the present study, FISH technique was carried out in 26 cases of Squamous cell carcinoma of the cervix using Centromere Enumeration Probes, CEP for chromosome 3 and 17. Statistical tests including ANOVA and Chi square tests were used to analyze the numerical chromosome aberration data obtained by FISH analysis. FISH technique was also carried out in 10 healthy samples (control) by using both CEP 3 and CEP 17 probe., Results and Discussion: FISH results of CEP 3 in the present study showed the frequent gains of chromosome 3 in Squamous cell carcinoma over the chromosome 17. ANOVA results were found to be significant for both CEP 3 and CEP-17 in Squamous cell carcinoma of the cervix. Chi square test (disease v/s control) was also used to study the significant difference between the patients and the controls and it was found to be significant for both chromosomes 3 and 17.

Background: Brinjal is an important vegetable crop. Major crop loss of brinjal is due to insect attack. Insect-resistant EE-1 brinjal has been developed and is awaiting approval for commercial release. Consumer health concerns and implementation of international labelling legislation demand reliable analytical detection methods for genetically modified (GM) varieties., Results: End-point and real-time polymerase chain reaction (PCR) methods were used to detect EE-1 brinjal. In end-point PCR, primer pairs specific to 35S CaMV promoter, NOS terminator and nptII gene common to other GM crops were used. Based on the revealed 3' transgene integration sequence, primers specific for the event EE-1 brinjal were designed. These primers were used for end-point single, multiplex and SYBR-based real-time PCR. End-point single PCR showed that the designed primers were highly specific to event EE-1 with a sensitivity of 20 pg of genomic DNA, corresponding to 20 copies of haploid EE-1 brinjal genomic DNA. The limits of detection and quantification for SYBR-based real-time PCR assay were 10 and 100 copies respectively., Conclusion: The prior development of detection methods for this important vegetable crop will facilitate compliance with any forthcoming labelling regulations., (Copyright © 2012 Society of Chemical Industry.)

Objectives: Essential hypertension is known to be associated with growth, development, and aging of humans. Telomeres are specialized nucleoprotein complexes consisting of tandem repeats of DNA sequences (TTAGGG)n that serve as protective caps of human chromosomes. Telomere length is considered as a biomarker of aging in somatic cells. In the present investigation, leukocyte telomere length was determined among hypertensive and normal individuals to find out the association, if any, with hypertension., Materials and Methods: Venous blood samples were collected from normal and hypertensive individuals with written informed consent approved by ethic committee of Department of Genetics, Osmania University Hyderabad, India. Genomic DNA was isolated from blood samples of 98 normal (age range: 30-70 years, mean age: 51.01 ± 10.12 years) and 96 hypertensive individuals (age range: 35-75 years, mean age: 49.18 ± 6.46 years). Using a SYBR green-based real time quantitative PCR relative telomere length was determined among these individuals., Results: The relative telomere length (T/S ratio) in hypertensive individuals was observed to be 0.91 ± 0.16 which was significantly different (P < 0.001) from normal individuals where the relative telomere length was 0.99 ± 0.13. No significant difference was observed between relative telomere length of male and female individuals, although there is negative correlation between age and telomere length was observed in both normal and hypertensive individuals. The systolic and diastolic blood pressure was negatively correlated with relative telomere length, though not significant., Conclusion: Shorter telomere length is associated with hypertensive individuals in Indian population., (Copyright © 2012 Wiley Periodicals, Inc.)