129 research outputs found
Role of salt precursors for the synthesis of zinc oxide nanoparticles and in imparting variable antimicrobial activity
Synthesis of nanoparticles (NPs) having unique potentials and properties is of great importance in nanotechnology. The NP synthesis techniques may include the wet chemistry to microbial incubation reduction methods. This work reports generation of ZnO NPs by identical preparation including incubation of different zinc salts i.e. zinc acetate, zinc chloride and zinc sulphate as precursors with cell free extracts of Bacillus circulans MTCC 7906 (Bc7906) and Pleurotus florida (Pf). The synthesized NPs exhibited variation in their absorption peaks in UV-Vis spectra which appeared at 275 nm, 325 nm and 375 nm with P. florida for the three salt precursors respectively while the Bc7906 generated ZnO NPs showed peaks between 300-350 nm. A variation in ZnO NP morphology ranged from 50 to 120 nm in size and spherical, oval, cylindrical to trigonal anisotropic in shape by transmission EM. Further, the rough and corrugated surface topography of ZnO NPs was observed in Scanning EM. The % weight for Zn element surface composition as recorded by SEM-EDS was observed to be highest for zinc acetate (2.34%) and zinc sulphate (7.54 %) on microbial synthesis from Bc7906 and Pf respectively. The antimicrobial potential of the synthesized ZnO NPs on human pathogenic and plant beneficial bacteria was tested and it was observed to be highest for microbially synthesized ZnO NPs using zinc acetate (15 mm) and zinc sulphate (14 mm) as salt precursors @ 10 ppm. This is the first report on differential antimicrobial behavior of ZnO NPs on human pathogenic and plant beneficial microbes
Antimycotic activity of biogenically synthesised metal and metal oxide nanoparticles against plant pathogenic fungus Fusarium moniliforme (F. fujikuroi)
263-270Consistent and injudicious application of antifungal agents to control fungal pathogens on crops results in off-target ill-effects on livestock and human health besides issues, such as disruption of ecological balance. In this context, development of novel specific antifungal agents such as metal or metal oxide nanoparticles without side effects becomes a necessity. Here, we attempted green synthesis of three different metal and metal oxide nanoparticles (NPs) (Ag, ZnO and FeO) by incubating metal salts with Trichoderma harzianum hyphal or mycelial extract (HE). The AgNPs were also generated using hyphal filtrate (HF). The synthesized nanoparticles were characterized by microscopy and spectroscopy techniques and evaluated by poisoned food technique/agar well diffusion technique under in vitro conditions on Czapek dox agar against plant pathogenic fungus Fusarium moniliforme. The tested NPs exhibited varied efficacy for curbing the growth of F. moniliforme. A NP concentration dependent increase in percent growth inhibition was recorded for the above mentioned three types of NPs. Moreover, the antimycotic efficacy of the microbial synthesized Ag NPs also varied for the T. harzianum cell free filtrate and hyphal extract formulations. Maximum percent hyphal growth inhibition (58.83%) was recorded for T. harzianum HE Ag NPs at 800 ppm followed by FeO NPs at 400 ppm (40.38%)
Various Challenges and Security Threats in Cloud Computing
Cloud computing is an assimilation and on demand delivery of various information technology resources and services. The process is built to initiate real-time actions and responses for the enormous multi-dimensional data generated by websites, devices, applications and other sources. The cloud computing provides cost saving, flexibility, mobility to the clients along with disaster recovery and loss prevention providing sustainability and competitive edge without letting them to shell out for the requisite infrastructure, installation and manpower to achieve and maintain such hi-tech infrastructure. Maximizing the quality and quantity of service and resources besides limiting the infrastructural cost are important necessities for this technology. Cloud computing has transformed the way many organizations use and share data and applications over Internet by efficient distribution and utilization of their resources and services. With so much data going into the cloud, particularly into public cloud services, these resources have become susceptible to various security threats and challenges. In this paper we have discussed some of the critical security concerns that prevent the adoptability of cloud computing
A comparison of three different gauge Quincke’s spinal needles in patients undergoing elective surgery under spinal anaesthesia: a prospective randomized study
Background: The present study was conducted to compare three different Quincke’s spinal needles i.e. 23, 25 and 26 gauge in patients undergoing elective surgery under spinal anaesthesia (SA).Methods: The prospective randomized double-blind study was conducted on 150 male patients in the age group of 18-50 yrs., having physical status class I to II, scheduled for elective surgery under SA. Patients were randomly divided into three groups comprising 50 patients each. SA was administered using Quincke’s spinal needles of 23, 25 and 26 gauge in group 1, 2 and 3 respectively. Ease of insertion, number of attempts and time of appearance of CSF and incidence of PDPH was recorded in all the patients.Results: Ease of insertion was graded easy in 98%, 84% and 82% in group 1, 2 and 3 respectively. First attempt success rate was highest in group 1, (98%). Meantime for appearance of CSF beyond hub was maximum in group 3 i.e. 14.60±2.56 sec. Mild PDPH was reported in 6% and 2% patients after 24 hrs in group 1 and group 2 respectively.Conclusions: Finer spinal needle proved to be more dependable in generating less traumatic effect on the dura and preventing PDPH but are technically more difficult thus decreasing first attempt success rate
Molecular characterization of a Y-derived marker chromosome and identification of indels in the DYS1 region in a patient with stigmata of Turner syndrome
Presence of the Y chromosome in human female and its absence in the male is an abnormal condition, implying a spectrum of genetic abnormalities. In this communication, we describe studies conducted on a 17-year-old patient (HK-459) with stigmata of Turner syndrome. We analysed the hormonal profile of the subject, chromosomal constitution and DNA for the five different loci encompassing both the arms of the Y chromosome. Chromosomal analysis showed mosaicism containing 45,X/46,X,+mar but no Y chromosome. The X chromosome and all the autosomes of the patient and her parents were normal. The Southern analysis of the patient's genomic DNA with probes specific to DYZ1 locus did not detect the corresponding Y-specific signal. Similarly, primers RG4, RG7 and PABY, corresponding to SRY gene and pseudoautosomal boundary regions respectively, failed to generate Y-specific amplicons. However, primers DYZ3 and DYS1, representing centromeric heterochromatic and euchromatic regions respectively, on the long arm of the Y chromosome uncovered Y-specific signals in the patient and her mother. Sequence analysis of DYS1-specific (710 bp) amplicon from the patient, both of her parents and two normal males showed insertion/deletion mutation in the patient. It is inferred that the Y-derived marker chromosome in the patient is of maternal origin and had undergone post-zygotic mutational events. The possible prognostic implications of this combined approach in the patient(s) with stigmata of Turner syndrome are discussed here
Naphthalimide based hybrid nanoparticles for selective recognition of Hg(II)
1,8-Naphthalic anhydride and cystamine dihydrochloride have been used as precursors for the synthesis of a dipodal compound (1) which has been further processed into fluorescent organic nanoparticles (N1) by re-precipitation technique. This has resulted in the formation of spherical nanoparticles which have been characterized by TEM and DLS studies. These hybrid nanomaterials composed of organic and inorganic nanoparticles have been used as a sensing platform for determination of mercury(II). The sensing phenomenon shows a ratiometric response for the selective determination with Hg2+ ion among other heavy metal ions with enhancement in fluorescence emission at 340 nm and decrease in emission intensity at 469 nm. Other heavy metal show no interference towards recognition of Hg2+ ion
Curcumin And Etoricoxib Encapsulated Liposomes: Formulation, Characterization And Anti-Inflammatory Effects In Rat Models
To enhance anti-inflammatory efficacy of Curcumin (CURC) and Etoricoxib (ETRX); and to reduce their notorious side effects, they were loaded into liposomal formulations (LFs). The present study aimed at formulation, characterization and evaluation of anti-inflammatory effects of LFs of CURC in combination with ETRX in experimental acute inflammation (AI) in rat model induced by carrageenan administration. The existing pharmaceuticals for treating arthritis are analgesics, steroids and non-steroidal anti-inflammatory drugs (NSAIDs), which reduce the symptoms such as severe pain and inflammation. Classical NSAIDs are cyclooxygenase (COX) inhibitors that inhibit prostaglandins (PGs) and thromboxane synthesis, thereby reducing inflammation. New NSAIDs selectively inhibit COX-2 and are usually specific to inflamed tissue, which decreases the risk of peptic ulcer. However, their long-term use cannot be sustained due to inadequate pain relief, immune disturbances and serious gastrointestinal and cardiovascular adverse events. Therefore, plant-based product like CURC with anti-inflammatory properties and minimum side effects are needed for the treatment of arthritis, including rheumatoid arthritis (RA) and osteoarthritis, especially after the withdrawal of many Food and Drug Administration (FDA)-approved anti- inflammatory drugs. However, its poor solubility, low chemical stability and short half-life following systemic absorption contribute to CURC being considered a pharmaceutical challenge. Numerous delivery systems have been proposed as means to tailor its biological properties. In this research, we are particularly interested in potential of CURC as an anti-inflammatory agent in combination with ETRX and delivery in the form of LFs. ETRX; a NSAID is proposed to treat inflammation in rat model as it is known for its anti-inflammatory, analgesic and antipyretic effects. ETRX, a widely prescribed anti- inflammatory drug belongs to class IΙ under BCS (biopharmaceutical classification system) and exhibit variable oral bioavailability due to its poor aqueous solubility. This research is aimed to study synergistic effect of a natural compound CURC and an allopathic NSAID moiety ETRX to treat inflammation in rat model, by oral ingestion in the form of LF as an efficient drug delivery system. Hence, we propose LF as a mean to overcome the CURC limitations. Liposomes (LPs) encapsulation of CURC makes this formulation amenable to circumvent the problem of poor oral availability that limits the utility of free CURC. The LFs can potentiate the effects of encapsulated drugs by sustaining the release over an extended period of time. The results of our study demonstrated that the association of CURC with ETRX in the form of LFs could potentiate the anti-inflammatory effects in reduced doses in vitro and in rat model. The LFs were spherical in shape in TEM images at various resolutions. The particle size of optimized CURC-ETRX LPs was found to be 276.1 nm with PDI value of 24.5. The maximum EE for CURC and ETRX in optimized formulation (F2) was found 98.915% and 93.877% respectively. The % EE of CURC-ETRX loaded LFs was found to be dependent on the lipid concentration, resulting almost quantitatively for a maximum 15 mg of total lipids (PC+CL) and progressively decreasing at higher 20 mg of total lipid (PC+CL) content, may be due to precipitation of drugs at higher lipid concentrations. The cumulative percentage release of CURC and ETRX from optimized formulations was found to be 59.64% and 83.11% respectively, for a period of 24 hours. We investigated the in vivo effect of CURC and ETRX loaded LF on local edema in carrageenan-induced paw edema in rat model. The percentage inhibition of edema in rat model was found to be better for CURC-ETRX LF in comparison to conventional CURC and ETRX in solution forms (p<0.05). Hence, the association of CURC and ETRX to a low dose in the form of LFs could be an appropriate combination to decrease NSAID doses used to reduce pain, inflammatory cytokines, and histological changes in AI
Immunological defect in leprosy patients: altered T-lymphocyte signals
The early events of activation were studied in paucibacillary (TT/BT) and multibacillary (BL/LL) leprosy patients by stimulation of their lymphocytes with mitogenic agents (calcium ionophore A23187/PMA) and Micobacterium leprae antigen (PGL-1). Maximum proliferation in response to PMA/A23187 and PGL-1 was observed in the BT/TT patients and the control group, respectively. Inositol triphosphate (IP3) and calcium were constitutively elevated in BT/TT and LL/BL patients. PMA/A23187 caused an increase in both IP3 and [Ca2+]i in BT/TT patients and controls. PGL-1 marginally increased IP3 levels in BT/TT patients. In the LL/BL patients, although PMA/A23187 increased IP3 levels, but no change was seen in [Ca2+]i, PGL-1 had no effect. Protein kinase C levels were seen to be associated with particulate fractions in BT/TT patients and were found to increase further in response to PMA/A23187. PGL-1 did not increase translocation of protein kinase C in controls or LL/BL patients. A preactivated and sensitised state of T-lymphocytes was observed in BT/TT patients, responsive to antigen and mitogens, whereas the cells of LL/BL patients were unresponsive to PGL-1. The altered signal transduction events characterised in the MB patients thus correlate well with the anergic state of their cells
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