Maternal footprints of Southeast Asians in North India

We have analyzed 7,137 samples from 125 different caste, tribal and religious groups of India and 99 samples from three populations of Nepal for the length variation in the COII/tRNA(Lys) region of mtDNA. Samples showing length variation were subjected to detailed phylogenetic analysis based on HVS-I and informative coding region sequence variation. The overall frequencies of the 9-bp deletion and insertion variants in South Asia were 1.9 and 0.6%, respectively. We have also defined a novel deep-rooting haplogroup M43 and identified the rare haplogroup H14 in Indian populations carrying the 9-bp deletion by complete mtDNA sequencing. Moreover, we redefined haplogroup M6 and dissected it into two well-defined subclades. The presence of haplogroups F1 and B5a in Uttar Pradesh suggests minor maternal contribution from Southeast Asia to Northern India. The occurrence of haplogroup F1 in the Nepalese sample implies that Nepal might have served as a bridge for the flow of eastern lineages to India. The presence of R6 in the Nepalese, on the other hand, suggests that the gene flow between India and Nepal has been reciprocal.     

Identification by Quantitative Carrier Test of Surrogate Spore-Forming Bacteria To Assess Sporicidal Chemicals for Use against Bacillus anthracis

The spores of six strains of Bacillus anthracis (four virulent and two avirulent) were compared with those of four other types of spore-forming bacteria for their resistance to four liquid chemical sporicides (sodium hypochlorite at 5,000 ppm available chlorine, 70,000 ppm accelerated H₂O₂, 1,000 ppm chlorine dioxide, and 3,000 ppm peracetic acid). All test bacteria were grown in a 1:10 dilution of Columbia broth (with manganese) incubated at 37°C for 72 h. The spore suspensions, heat treated at 80°C for 10 min to rid them of any viable vegetative cells, contained 1 × 10⁸ to 3 × 10⁸ CFU/ml. The second tier of the quantitative carrier test (QCT-2), a standard of ASTM International, was used to assess for sporicidal activity, with disks (1 cm in diameter) of brushed and magnetized stainless steel as spore carriers. Each carrier, with 10 μl (≥10⁶ CFU) of the test spore suspension in a soil load, was dried and then overlaid with 50 μl of the sporicide being evaluated. The contact time at room temperature ranged from 5 to 20 min, and the arbitrarily set criterion for acceptable sporicidal activity was a reduction of ≥10⁶ in viable spore count. Each test was repeated at least three times. In the final analysis, the spores of Bacillus licheniformis (ATCC 14580^T) and Bacillus subtilis (ATCC 6051^T) proved to be generally more resistant than the spores of the strains of B. anthracis tested. The use of one or both of the safe and easy-to-handle surrogates identified here should help in developing safer and more-effective sporicides and also in evaluating the field effectiveness of existing and newer formulations in the decontamination of objects and surfaces suspected of B. anthracis contamination.     

Rapid Screening Method for Mycobactericidal Activity of Chemical Germicides That Uses Mycobacterium terrae Expressing a Green Fluorescent Protein Gene

The slow growth of mycobacteria in conventional culture methods impedes the testing of chemicals for mycobactericidal activity. An assay based on expression of the green fluorescent protein (GFP) by mycobacteria was developed as a rapid alternative. Plasmid pBEN, containing the gene encoding a red-shifted, high-intensity GFP mutant, was incorporated into Mycobacterium terrae (ATCC 15755), and GFP expression was observed by epifluorescence microscopy. Mycobactericidal activity was assessed by separately exposing a suspension of M. terrae(pBEN) to several dilutions of test germicides based on 7.5% hydrogen peroxide, 2.4% alkaline glutaraldehyde, 10% acid glutaraldehyde, and 15.5% of a phenolic agent for contact times ranging from 10 to 20 min (22°C), followed by culture of the exposed cells in broth (Middlebrook 7H9) and measurement of fluorescence every 24 h. When the fluorescence was to be compared with CFU, the samples were plated on Middlebrook 7H11 agar and incubated for 4 weeks. No increase in fluorescence or CFU occurred in cultures in which the cells had been inactivated by the germicide concentrations tested. Where the test bacterium was exposed to ineffective levels of the germicides, fluorescence increased after a lag period of 1 to 7 days, corresponding to the level of bacterial inactivation. In untreated controls, fluorescence increased rapidly to reach a peak in 2 to 4 days. A good Pearson correlation coefficient (r ≥0.85) was observed between the intensity of fluorescence and the number of CFU. The GFP-based fluorescence assay reduced the turnaround time in the screening of chemical germicides for mycobactericidal activity to ≤7 days.     

Splenic peliosis – a potentially fatal condition which can mimick malignancy

Isolated splenic peliosis is an extremely rare occurrence, and this disease often manifests itself with spontaneous haemoperitoneum.We report a case where an otherwise healthy patient was found to have splenomegaly on clinical examination. On computerised tomography, a diagnosis of splenic malignancy was made, and the patient underwent a splenectomy. Histological examination gave the diagnosis of splenic peliosis, which had not been considered prior to the operation. In retrospect, splenectomy was the most prudent course of action, as the risk of spontaneous haemorrhage and fatality was eliminated. This case emphasises the need to retain an index of suspicion for this condition, even in otherwise healthy patients, and is a reminder of the usefulness of total splenectomy in the current era of minimally invasive diagnostic techniques.     

The morphology and electrophysiology of the neurones of the paired pedal ganglia of Lymnaea stagnalis (L.)

1. A morphological and electrophysiological map of the identifiable neurones and neuronal clusters of the paired pedal ganglia has been prepared. 2. Neuronal morphology was investigated using the fluorescent dye, Lucifer Yellow CH, whilst electrophysiological properties were studied using conventional intracellular recording techniques and the phase plane technique. 3. The paired pedal ganglia are largely symmetrical and giant neurones usually have contralateral homologues. 4. Neuronal clusters are also paired, but minor asymmetries, both of identifiable neurones and neuronal clusters have been found to exist. 5. These asymmetries are thought to be related to asymmetries of body form. 6. Most of the individually identifiable neurones possess obligatory axon branches which are invariant from one preparation to the next, but variant branches also occur. 7. Within the neuronal clusters, morphology appears to be more variable. 8. Individually identifiable neurones and neuronal clusters were characterized electrophysiologically according to the criteria of action potential shape, spontaneous activity pattern, electrical coupling and common synaptic inputs. 9. Homologous pairs of neurones usually have similar electrophysiological properties, as do those within clusters. 10. A number of wide-acting synaptic inputs have been identified on neurones of the pedal, buccal, visceral and parietal ganglia.     

Use of FabV-Triclosan Plasmid Selection System for Efficient Expression and Production of Recombinant Proteins in Escherichia coli

Maintenance of recombinant plasmid vectors in host bacteria relies on the presence of selection antibiotics in the growth media to suppress plasmid -free segregants. However, presence of antibiotic resistance genes and antibiotics themselves is not acceptable in several applications of biotechnology. Previously, we have shown that FabV-Triclosan selection system can be used to select high and medium copy number plasmid vectors in E. coli. Here, we have extended our previous work and demonstrated that expression vectors containing FabV can be used efficiently to express heterologous recombinant proteins in similar or better amounts in E. coli host when compared with expression vectors containing β-lactamase. Use of small amount of non-antibiotic Triclosan as selection agent in growth medium, enhanced plasmid stability, applicability in various culture media, and compatibility with other selection systems for multiple plasmid maintenance are noteworthy features of FabV-Triclosan selection system.     

Studies on serum gamma-glutamyl transpeptidase in primary idiopathic hypothyroidism patients.

Variations in the levels of serum gamma-glutamyl transpeptidase (GGT) were measured in control subjects and in 39 adult primary idiopathic hypothyroidism (PIH) patients. The serum GGT activity was low in PIH patients compared to that of control subjects. A more significant correlation was found between serum GGT and T3 (r = 0.766) but not with T4 (r = 0.476). The comparison of serum GGT with TSH has revealed that those two parameters are not parallel with each other (r = -0.454). No significant correlation between serum GGT activity, age, and sex in PIH patients and control subjects was observed. The present available data indicate that measurement of serum GGT might be useful as a marker index in PIH patients.     

Isolation and properties of enhancer-bypass mutants of sigma 54

The N-terminal activation domain of Escherichia coli sigma 54 was randomly mutated to provide a library of changes that might allow the required enhancer function to be bypassed. Five clones harbouring mutant sigma factors were obtained that exhibited this property in that they enhanced growth under nitrogen-limiting conditions in cells lacking NtrC. DNA sequence analysis located all mutations to four leucines in a small region between amino acids 25 and 31. No mutant sigma factors retained the hydrophobic character of the leucine residues. Mutant sigma factors were shown to transcribe in vitro without the need for enhancer binding activator or ATP hydrolysis, confirming the in vivo phenotype. These and other data suggest that a very small set of leucines is critical for keeping polymerase function in check, allowing high responsiveness to physiological induction via enhancer proteins such as NtrC.