Determination of Qnr allele frequencies in Fluoroquinolone resistant Pseudomonas aeruginosa isolated from burn wounds.

Effective treatment of burn wound infections is precluded by high prevalence of nosocomial infections coupled with high resistance rates against commonly used antimicrobials. Pseudomonas aeruginosa is an important nosocomial pathogen in burn infections due to high morbidity and mortality associated with it. We analyzed fluoroquinolone resistant Pseudomonas aeruginosa for the presence of Qnr gene, owing to high genetic mobility of this plasmid-borne gene. Bacteria were isolated from burn wound patients from Pak-Italian ModernBurn Center, Nishter Hospital Multan. Fluoroquinoloneresistant isolates were selected and PCR-based assay was designed to determine the frequencies of different alleles. QnrB was found in highest number of isolates (10.8%) followed by QnrD (6%). We could not find any QnrC positive sample. As far as we could search, this is the first report on detection of Qnr gene in Pseudomonas aeruginosa from Pakistan.

Biosynthesized composites of Au-Ag nanoparticles using Trapa peel extract induced ROS-mediated p53 independent apoptosis in cancer cells.

The current study highlights rapid, sustainable, and cost-effective biosynthesis of silver (Ag), gold (Au) nanoparticles (NPs), and bimetallic Au-AgNPs composites using bio-waste extract of Trapa natans. Growth of the NPs was monitored spectrophotometrically and peak was observed at ∼525 nm, ∼450 nm, and ∼495 nm corresponding to Plasmon absorbance of AuNPs, AgNPs, and Au-AgNPs, respectively. Transmission electron microscopy (TEM) revealed the size of AgNPs (∼15 nm), AuNPs (∼25 nm), and Au-AgNPs (∼26-90 nm). Synthesized NPs follow the Gaussian bell curve and its crystalline nature was identified by X-ray diffraction (XRD). Furthermore, Au-AgNPs induced cytotoxicity in various cancer cells (HCT116, MDA-MB-231, and HeLa) effectively at 200 µg/mL. Au-AgNPs-exposed cancer cells exhibited apoptotic features such as nuclear condensation, mitochondrial membrane potential loss, and cleavage of casp-3 and poly (ADP-ribose) polymerase-1 (PARP). Au-AgNPs exposure enhanced reactive oxygen species (ROS) and upon inhibition of ROS, apoptosis was reduced effectively. NPs treatment killed HCT116 WT and p53 knockout cells without any significant difference. Mechanistically, Au-AgNPs derived with Trapa peel extract significantly enhance ROS which trigger p53-independent apoptosis in various cancer cells effectively. Our study explores the use of bio-waste for the green synthesis of NPs, which can be attractive candidates for cancer therapy.

Biosynthesis of Silver Nanoparticles from Desmodium triflorum: A Novel Approach Towards Weed Utilization.

A single-step environmental friendly approach is employed to synthesize silver nanoparticles. The biomolecules found in plants induce the reduction of Ag(+) ions from silver nitrate to silver nanoparticles (AgNPs). UV-visible spectrum of the aqueous medium containing silver ions demonstrated a peak at 425 nm corresponding to the plasmon absorbance of silver nanoparticles. Transmission electron microscopy (TEM) showed the formation of well-dispersed silver nanoparticles in the range of 5-20 nm. X-ray diffraction (XRD) spectrum of the AgNPs exhibited 2θ values corresponding to the silver nanocrystal. The process of reduction is extracellular and fast which may lead to the development of easy biosynthesis of silver nanoparticles. Plants during glycolysis produce a large amount of H(+) ions along with NAD which acts as a strong redoxing agent; this seems to be responsible for the formation of AgNPs. Water-soluble antioxidative agents like ascorbic acids further seem to be responsible for the reduction of AgNPs. These AgNPs produced show good antimicrobial activity against common pathogens.

Rapid synthesis of silver nanoparticles using dried medicinal plant of basil.

Plants respond to heavy metal stress by metal complexation process like production of phytochelations or by other metal chelating peptides. In this paper we report the synthesis of silver nanoparticles (AgNPs) from the room dried stem and root of Ocimum sanctum. The broth of the plant is used as a reducing agent for the synthesis of Ag nanoparticles at room temperature. The reaction process was simple and was monitored by ultraviolet-visible spectroscopy (UV-vis). There was formation of highly stable silver nanoparticles in the solution. The morphology and crystalline phase of the NPs were determined from transmission electron microscopy (TEM), selected area electron diffraction (SAED) and X-ray diffraction (XRD) spectra. Transmission Electron Microscopy studies showed that the silver nanoparticles obtained from roots and stem were of sizes 10+/-2 and 5+/-1.5 nm, respectively. The various phytochemicals present within the ocimum plant result in effective reduction of silver salts to nanoparticles but their chemical framework is also effective at wrapping around the nanoparticles to provide excellent robustness against agglomeration.

Comparing genomes of Helicobacter pylori strains from the high-altitude desert of Ladakh, India.

The genomic diversity of Helicobacter pylori from the vast Indian subcontinent is largely unknown. We compared the genomes of 10 H. pylori strains from Ladakh, North India. Molecular analysis was carried out to identify rearrangements within and outside the cag pathogenicity island (cag PAI) and DNA sequence divergence in candidate genes. Analyses of virulence genes (such as the cag PAI as a whole, cagA, vacA, iceA, oipA, babB, and the plasticity cluster) revealed that H. pylori strains from Ladakh are genetically distinct and possibly less virulent than the isolates from East Asian countries, such as China and Japan. Phylogenetic analyses based on the cagA-glr motifs, enterobacterial repetitive intergenic consensus patterns, repetitive extragenic palindromic signatures, the glmM gene mutations, and several genomic markers representing fluorescent amplified fragment length polymorphisms revealed that Ladakhi strains share features of the Indo-European, as well as the East Asian, gene pools. However, the contribution of genetic features from the Indo-European gene pool was more prominent.

The cag pathogenicity island of Helicobacter pylori is disrupted in the majority of patient isolates from different human populations.

The cag pathogenicity island (cag-PAI) is one of the major virulence determinants of Helicobacter pylori. The chromosomal integrity of this island or the lack thereof is speculated to play an important role in the progress of the gastroduodenal pathology caused by H. pylori. We determined the integrity of the cag-PAI by using specific flanking and internally anchored PCR primers to know the biogeographical distribution of strains carrying fully integral cag-PAI with proinflammatory behavior in vivo. Genotypes based on eight selected loci were studied in 335 isolates obtained from eight different geographic regions. The cag-PAI appeared to be disrupted in the majority of patient isolates throughout the world. Conservation of cag-PAI was highest in Japanese isolates (57.1%). However, only 18.6% of the Peruvian and 12% of the Indian isolates carried an intact cag-PAI. The integrity of cag-PAI in European and African strains was minimal. All 10 strains from Costa Rica had rearrangements. Overall, a majority of the strains of East Asian ancestry were found to have intact cag-PAI compared to strains of other descent. We also found that the cagE and cagT genes were less often rearranged (18%) than the cagA gene (27%). We attempted to relate cag-PAI rearrangement patterns to disease outcome. Deletion frequencies of cagA, cagE, and cagT genes were higher in benign cases than in isolates from severe ulcers and gastric cancer. Conversely, the cagA promoter and the left end of the cag-PAI were frequently rearranged or deleted in isolates linked to severe pathology. Analysis of the cag-PAI genotypes with a different biogeoclimatic history will contribute to our understanding of the pathogen-host interaction in health and disease.

Maxillofacial trauma: current practice in management at Pakistan Institute of Medical Sciences.

BACKGROUND: This study was carried out to determine the aetiology, pattern and management of maxillofacial injuries at PIMS, Islamabad. METHODS: This descriptive study was conducted at Plastic Surgery Department, PIMS Islamabad from 1st February 1998 to 30th April 2002. All the adult patients presenting with maxillofacial injures were included where as patients less than 12 years of age and only facial lacerations were excluded. Similarly isolated nasal bone fractures were also excluded because these patients were routinely managed by ENT department. Age, sex, presentation, aetiology, associated injuries and treatment modalities undertaken in these patients were recorded. RESULTS: In 164 patients 254 fractures were noted. Most were male (86%), ranging in age from 13-71 years with a male to female ratio of 6:1 respectively. The most frequent (48%) cause noticed was road traffic accidents followed by assault. Mandible was the commonest to be involved in such injuries followed by maxilla. Most of the patients (32%) had associated facial injuries. Various treatment modalities were practiced. CONCLUSION: Maxillofacial fractures should be managed by open reduction and internal fixation as early as possible.