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DrRecA and PprA proteins function are crucial for the extraordinary resistance to γ-radiation and DNA strand break repair in Deinococcus radiodurans . DrRecA mediated homologous recombination help in DNA strand break repair and cell survival, while the PprA protein confers radio-resistance via its roles in DNA repair, genome maintenance, and cell division. Genetically recA and pprA genes interact and constitute an epistatic group however, the mechanism underlying their functional interaction is not clear. Here, we showed the physical and functional interaction of DrRecA and PprA protein both in solution and inside the cells. The absence of the pprA gene increases the recombination frequency in gamma-irradiated D. radiodurans cells and genomic instability in cells growing under normal conditions. PprA negatively regulates the DrRecA functions by inhibiting DrRecA mediated DNA strand exchange and ATPase function in vitro . Furthermore, it is shown that the inhibitory effect of PprA on DrRecA catalyzed DNA strand exchange was not due to sequestration of homologous dsDNA and was dependent on PprA oligomerization and DNA binding property. Together, results suggest that PprA is a new member of recombination mediator proteins (RMPs), and able to regulate the DrRecA function in γ-irradiated cells by protecting the D. radiodurans genome from hyper-recombination and associated negative effects.

High-linear energy transfer (LET) radiation is a promising alternative to conventional low-LET radiation for therapeutic gain against cancer owing to its ability to induce complex and clustered DNA lesions. However, the development of radiation resistance poses a significant barrier. The potential molecular mechanisms that could confer resistance development are translesion synthesis (TLS), replication gap suppression (RGS) mechanisms, autophagy, epithelial-mesenchymal transition (EMT) activation, release of exosomes, and epigenetic changes. This article will discuss various types of complex clustered DNA damage, their repair mechanisms, mutagenic potential, and the development of radiation resistance strategies. Furthermore, it highlights the importance of careful consideration and patient selection when employing high-LET radiotherapy in clinical settings.

In the present study Zinc Oxide (ZnO) nanoparticles and Rare Earth (RE) ion Cerium (Ce) doped ZnO nanoparticles were synthesized by chemical precipitation technique. The synthesized nanoparticles were characterized by X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscope (TEM), photoluminescence spectroscopy (PL), UV–visible spectroscopy and ferromagnetism behavior at room temperature. The XRD and EDX analysis revealed that Ce doped ZnO pattern matched with the ZnO pattern i.e. they exhibited hexagonal wurtzite structure and Ce ions were successfully incorporated into the ZnO nanoparticles. TEM images illustrated the average diameter of synthesized nanoparticles. The average diameter of ZnO and Ce doped ZnO nanoparticles was around 20 nm. PL measurements revealed that ZnO nanoparticles and Ce doped ZnO nanoparticles had an UV emission and a green emission while the Ce ions doping induced a red shift in the UV emission with broadening in the green emission. Direct type of transition of band gaps was confirmed by transmission spectra occurring at 3.5 and 3.2 eV respectively for ZnO nanoparticles and Ce doped ZnO nanoparticles i.e. decrease of band gap energy with doping of Ce ions in ZnO nanoparticles. The magnetization study on the Ce doped ZnO nanoparticles exposed outstanding ferromagnetism property at room temperature.

The present study evaluates the performance of OptiMAL-IT test and nested PCR assay in detection of malaria parasites. A total of 76 randomly selected blood samples collected from two malaria endemic areas were tested for malaria parasites using microscopy and OptiMAL-IT test in the field. PCR assays were performed in the laboratory using DNA extracted from blood spots of the same samples collected on the FTA classic cards. Of the total of 61 field confirmed malaria positive samples, only 58 (95%) were detected positive using microscopy in the laboratory. Sensitivity, specificity, positive predictive value, negative predictive value and false discovery rate of OptiMal-IT in comparison to the microscopy were 93%, 83%, 95%, 79% and 5%, respectively. On the other hand, the sensitivity and specificity of PCR assay were 97% and 100%, respectively, whereas positive predictive value, negative predictive value and false discovery rate were 100%, 90% and 0%, respectively. The overall performance of OptiMal-IT and PCR assays for malaria diagnosis was 76% and 97%, respectively. PCR assay enabled the identification of infection with Plasmodium malariae Laveran, 1881 in four samples misidentified by microscopy and Plasmodium-specific antigen (PAN) identified by the OptiMAL-IT test. In addition to the standard methods, such PCR assay could be useful to obtain the real incidence of each malaria parasite species for epidemiological perspectives.

Introduction: Chloroquine resistance in Plasmodium falciparum is associated with mutations in pfcrt and pfmdr1 genes. The frequency distribution of pfcrt K76T and pfmdr1 N86Y mutations and their association with chloroquine susceptibility was studied in an endemic area along the Indo-Bangladesh border. Methodology: A single-arm prospective study of clinical and parasitological responses in P. falciparum malaria patients to chloroquine was conducted in vivo. PCR-RFLP assay was used to detect pfcrt K76T and pfmdr1 N86Y mutations in P. falciparum. The PCR products of pfcrt gene were sequenced,  translated and aligned for haplotyping. Results: Out of 63 cases, 44 (69.8%) responded adequately to chloroquine treatment. Pfcrt K76T mutation was recorded in 100% of the treatment failure cases, whereas pfmdr1 N86Y mutation was found in 52.6% of the cases only. Early treatment failure (84.2%) occurred more frequently than late treatment failure (15.8%). Kaplan–Meier survival analysis showed that the probability estimate for treatment success after 7 and 15 days was 0.84 (95% CI = 0.72-0.92) and 0.70 (95% CI = 0.57-0.80), respectively. Sequence analysis of 72 to 76 pfcrt gene codons revealed the presence of two mutant (CVMNT, CVIET) and two wild (CVMNK, CVIEK) haplotypes. The mutant CVIET haplotype was predominantly distributed (42.1%). Conclusions: The presence of mutations in pfcrt K76T and pfmdr1 N86Y genes is not sufficient to explain the therapeutic efficacy of chloroquine to P. falciparum. Study suggests that pfcrt K76T mutant haplotypes are widely distributed and are spreading diligently, which needs to be taken into account in devising an antimalarial policy.

In this report, undoped ZnO and Er doped ZnO nanostructures [Zn 1−x Er x O, where x = 1, 3, 5 and 7 at.%] were synthesized by chemical precipitation technique. The chemical precipitation route for the preparation of undoped ZnO and Er doped ZnO nanostructures at different concentrations represents an easy, fast and efficient method. The synthesized nanostructures were characterized to analyze their crystal structure, crystal morphology, optical and magnetic properties using X-ray diffraction (XRD), Energy dispersive X-ray (EDX), High resolution scanning electron microscopy (HRSEM), Ultraviolet–Visible spectroscopy (UV–Visible), Photoluminescence spectroscopy (PL) and Vibrating sample magnetometer (VSM) respectively. The XRD studies exposed that undoped ZnO and all Er doped ZnO samples have a hexagonal wurtzite crystal structure. The XRD results showed that Er 3+ ions were successfully doped into ZnO nanostructures as no diffraction peaks of Er or erbium oxide were observed in the pattern. EDX results also confirmed that Er ions were successfully incorporated into the lattice position of Zn ions in ZnO. HRSEM characterization showed that presence of Er 3+ ions in crystal structure of ZnO can change the morphology i.e. the transformation of nanorods to nanocones. Nanorods-like structure obtained with 1 at.% Er extend to nanocones-like for 3–7 at.% Er doped ZnO with changes in length and thickness in nm range. In UV–Visible absorbance spectra, a red shift was observed in the band gap of undoped ZnO and Er doped nanostructures with increasing Er concentration. PL measurements also revealed that the undoped ZnO and Er doped ZnO nanostructures had an UV emission, a defect emission and the Er ions doping induced a red shift in the UV emission with a small enhancement in the defect emission. The VSM study revealed that the undoped ZnO and Er doped ZnO nanostructures exhibit paramagnetic and ferromagnetic behaviour at room temperature respectively.

Low cost energy-efficient (power based) routing protocols of mobile ad hoc networks (MANETs) increase the lifetime of static networks by using received signal strength (RSS) and battery power status (PS). They require GPS service to find the exact location of mobile nodes. The GPS devices themselves consume power because they need excessive updates to find the stationary nodes for efficient routing. To overcome this, RSS is being used as a metric, followed by, residual battery power. The recent protocols, based on these concepts, provide energy efficient routes during the route discovery phase only. Topological changes make these routes weak in due course of time. To update routes, HELLO process can be used, which however creates unnecessary overhead, delay and consumes power. Hence, these protocols do not update the routes. We propose an energy-efficient reactive routing protocol that uses the RSS and PS of mobile nodes. Proposed Link Failure Prediction (LFP) algorithm uses the link-layer feedback system to update active routes. We use ns2 for simulation of the proposed algorithm. Comparing the results of proposed scheme and existing scheme, in terms of energy consumption, link failure probability, and retransmission of packets, we observe that the proposed scheme outperforms the existing one.

This study describes the mechanism of interfacial interaction of the MgO layer with TiO2 films and demonstrates the modification in optical and photovoltaic properties of MgO/TiO2/ITO heterostructures. X-ray diffraction, field emission scanning electron microscopy (FESEM), UV-visible spectroscopy, and x-ray absorption near-edge structure (XANES) at O K-edge, Mg K-edge, and Ti K-edge have been employed to characterize the MgO/TiO2/ITO heterostructures. The photovoltaic properties of heterostructures are studied using a solar simulator. FESEM results confirmed the spherical shape of MgO and TiO2 nanoparticles. Hybridization among the frontier orbitals of O, Mg, and Ti and the presence of Mg2+ and Ti4+ ions are confirmed by XANES studies. Assimilation of the MgO layer on TiO2 film resulted in a significant enhancement in the absorbance characteristics. The MgO film, deposited with maximum spin-coating speed 5000 rpm, exhibited the highest fill factor (FF=0.78), high short-circuit current (Isc = 12.20 mA/cm2), and open-circuit voltage (Voc = 0.93 V). The mechanism of high FF in MgO/TiO2/ITO structures has been discussed by considering the transparency and electron scavenging from the heterostructures.

Zinc oxide (ZnO) is a versatile and cost-effective semiconductor with an increased direct energy gap, making it suitable for various technological and scientific applications. In this study, we report the successful fabrication of ZnO and ZnO:Ag films on glass substrates using a combination of two solution-based techniques: the sol–gel method and screen printing. After sintering, the produced films were characterized using X-ray diffraction, optical transmission, and photoluminescence measurements. The X-ray diffraction analysis revealed a hexagonal (wurtzite) phase structure and polycrystalline nature, with a preferred orientation along the (101) plane. The crystallite size increased from 64 to 68 nm upon the substitution of silver (Ag) in the ZnO structure. Both optical transmission and photoluminescence characterizations confirmed a red shift in the ZnO:Ag films. The energy gap narrowed from 3.27 to 3.23 eV with the incorporation of Ag into ZnO. This observed increase in crystallite size and the reduction of the energy gap can be attributed to the successful substitution of Ag in the ZnO lattice.

The original version of this article was published with the following error. This has been corrected with this erratum.