Real-time polymerase chain reaction assay for rapid and sensitive detection of anthrax spores in spiked soil and talcum powder

Real-time polymerase chain reaction (real-time PCR) is a laboratory technique based on PCR. This technique is able to detect sequence-specific PCR products as they accumulate in “real time” during the PCR amplification, and also to quantify the number of substrates present in the initial PCR mixture before amplification begins. In the present study, real-time PCR assay was employed for rapid and real-time detection of Bacillus anthracis spores spiked in 0.1 g of soil and talcum powder ranging from 5 to 10⁷ spores. DNA was isolated from spiked soil and talcum powder, using PBS containing 1 % Triton-X-100, followed by heat treatment. The isolated DNA was used as template for real-time PCR and PCR. Real-time PCR amplification was obtained in 60 min under the annealing condition at 60°C by employing primers targeting the pag gene of B. anthracis. In the present study, the detection limit of real-time PCR assay in soil was 10³ spores and10² spores in talcum powder, respectively, whereas PCR could detect 10⁴ spores in soil and 10³ spores in talcum powder, respectively.     

Ultrasensitive cDNA detection of dengue virus RNA using electrochemical nanoporous membrane-based biosensor

A nanoporous alumina membrane-based ultrasensitive DNA biosensor is constructed using 5'-aminated DNA probes immobilized onto the alumina channel walls. Alumina nanoporous membrane-like structure is carved over platinum wire electrode of 76 μm diameter dimension by electrochemical anodization. The hybridization of complementary target DNA with probe DNA molecules attached inside the pores influences the pore size and ionic conductivity. The biosensor demonstrates linear range over 6 order of magnitude with ultrasensitive detection limit of 9.55×10(-12) M for the quantification of ss-31 mer DNA sequence. Its applicability is challenged against real time cDNA PCR sample of dengue virus serotype1 derived from asymmetric PCR. Excellent specificity down to one nucleotide mismatch in target DNA sample of DENV3 is also demonstrated.     

HIV-associated nephropathy: role of AT2R

AT₁R has been reported to play an important role in the progression of HIV-associated nephropathy (HIVAN); however, the effect of AT₂R has not been studied. Age and sex matched control (FVB/N) and Tg26 mice aged 4, 8, and 16 weeks were studied for renal tissue expression of AT₁R and AT₂R (Protocol A). Renal tissue mRNA expression of AT₂R was lower in Tg26 mice when compared with control mice. In Protocol B, Tg26 mice were treated with either saline, telmisartan (TEL, AT₁ blocker), PD123319 (PD, AT₂R blocker), or TEL + PD for two weeks. TEL-receiving Tg26 (TRTg) displayed less advanced glomerular and tubular lesions when compared with saline-receiving Tg26 (SRTg). TRTgs displayed enhanced renal tissue AT₂R expression when compared to SRTgs. Diminution of renal tissue AT₂R expression was associated with advanced renal lesions in SRTgs; whereas, upregulation of AT₂R expression in TRTgs was associated with attenuated renal lesions. PD-receiving Tg26 mice (PDRTg) did not show any alteration in the course of HIVAN; whereas, PD + TEL-receiving Tg26 (PD-TRTg) showed worsening of renal lesions when compared to TRTgs. Interestingly, plasma as well as renal tissues of Tg26 mice displayed several fold higher concentration of Ang III, a ligand of AT₂R.     

Adsorption of Heavy Metals by Paenibacillus validus Strain MP5 Isolated from Industrial Effluent–Polluted Soil

The present investigation was carried out to isolate bacterial strains from soil/mud samples of metal-polluted environment to check whether the natural adaptation of microbes has equipped them for bioremediation of toxic heavy metals. The primary and secondary screening resulted in 50 mesophilic autotrophic isolates of microbial consortium adapted for metal tolerance and bioadsorption potentiality. The multimetal tolerance in bacterial strain was developed by sequential transfer to higher concentrations of Cd, Cr, Cu, Pb, Ni, and Zn. The isolates were checked for their biosolubilization potential with copper-containing metal sulfide ores, viz. chalcopyrite exhibited 64% and covellite 54% solubilization in the presence of 10^?3 M multiple heavy metals on the fifth day at 35°C and pH 6.0. Metal adsorption of highly potential isolate, i.e., Paenibacillus validus MP5, studied by inductively coupled plasma optical emission spectroscopy (ICP-OES), showed maximum adsorption of Zn 27%, followed by Ni and Cd 16%, Cr 15%, Co 9%, and Pb 7.5% in chalcopyrite, which suggested its possible role in decontamination of metal-polluted sites.     

Invasive plants – Do they devastate or diversify rural livelihoods? Rural farmers’ perception of three invasive plants in Nepal

In this paper, we examine how rural people in the buffer zone of Chitwan National Park in Nepal perceive the effects of accidently transported invasive plant species, such as Mikania micrantha, Lantana camara and Chromolaena odorata, on their livelihoods. We found that their perception of the impact of each species on their livelihood varies with factors such as the duration of the presence of invasive plants in the landscape, and household characteristics. Results of a household survey indicate that farm households close to the forests have responded to the invasive species both as a victim and a beneficiary. Farm households are likely to adapt to the invaded environment as they have a history of interacting with invasive plants and can commoditise them through appropriate intervention. Additionally, the findings indicate that rural people are willing to invest in the control and management of invasive plants if appropriate technical assistance is available. Without assistance, they consider mitigating the infestation an unattainable mission and consider acceptance of the invasive species as a part of the rural ecosystem an inevitable outcome.