Molecular Assessments of Antimicrobial Protein Enterocins and Quorum Sensing Genes and Their Role in Virulence of the Genus Enterococcus.

Enterococcus has emerged as an opportunistic pathogen because of its antibiotic resistance and virulence profile, which makes it a causative agent of several diseases like endocarditis, surgical site, and urinary tract infections. Currently, species of this genus are the 2nd most frequently isolated microorganisms from hospital-acquired infections. Significant association with hospitals and unhygienic conditions of the environments has made them resistant to a wide range of antibiotics. On the brighter side, enterococci have the ability to produce antimicrobial proteins (i.e., enterocins) that exhibit wide antagonistic activity, thus making them useful microbes in the food and pharmaceutical industries. Enterocins are also involved in niche control in gut microbiota which is regulated by the quorum sensing (QS) system. A bacterial communication system that is controlled by the fsr operon in enterococci consists of FsrABDC, ef1097, and GelE/SprE genes. Hence, the present study was conducted for molecular assessment of enterocins and quorum sensing genes, inter-environmental correlation, and species prevalence of enterococci isolated from different environmental niches of Karachi, Pakistan. Obtained results revealed the highest prevalence of E. faecium and E. faecalis in all environments. Bacterial antagonism and enterocin genes were observed significantly high in poultry environments. The inter-environmental correlation indicated a strong positive correlation of freshwater with sewage and soil environments. Similarly, the fsr regulatory system was mostly identified in poultry-related environments, and a significant correlation between QS system and biofilm formation was established. In conclusion, this study confirmed the high prevalence of E. faecium in all tested sources, high enterocin production in non-clinical environments, and more fsr regulatory genes in poultry-related environments.

Unleashing the potential of vanillic acid: A new twist on nature's recipe to fight inflammation and circumvent azole-resistant fungal infections.

Vanillic acid (VA) - a naturally occurring phenolic compound in plants - is not only used as a flavoring agent but also a prominent metabolite post tea consumption. VA and its associated compounds are believed to play a significant role in preventing diseases, underscoring the need for a systematic investigation. Herein, we report a 4-step synthesis employing the classical organic reactions, such as Willamson's alkylation, Fischer-Spier reaction, and Steglich esterification, complemented with a protection-deprotection strategy to prepare 46 VA derivatives across the five series (1a-1i, 2a-2i, 3, 3a-3i, 4a-4i, 5a-5i) in high yields. The synthesized compounds were investigated for their antifungal, anti-inflammatory, and toxic effects. Notably, compound 1a demonstrated remarkable ROS inhibition with an IC50 value of 5.1 ± 0.7 µg/mL, which is more than twice as effective as the standard ibuprofen drug. A subset of the synthesized derivatives (2b, 2c, 2e, 3b-3d, 4a-4c, 5a, and 5e) manifested their antifungal effect against drug-resistant Candida strains. Compound 5g, in particular, revealed synergism with the established antifungal drugs amphotericin B (AMB) and fluconazole (FLZ), doubling FLZ's potency against azole resistant Candida albican ATCC 36082. Furthermore, 5g improved the potency of these antifungals against FLZ-sensitive strains, including C. glabrata ATCC 2001 and C. parapsilosis ATCC 22019, as well as various multidrug-resistant (MDR) Candida strains, namely C. albicans ATCC 14053, C. albicans CL1, and C. krusei SH2L OM341600. Additionally, pharmacodynamics of compound 5g was examined using time-kill assay, and a benign safety profile was observed with no hemolytic activity in whole blood, and no cytotoxicity towards the normal BJ human cell line. The synergistic potential of 5g was further investigated through both experimental methods and docking simulations.These findings highlight the therapeutic potential of VA derivatives, particularly in addressing inflammation and circumventing FLZ resistance in Candida albicans.

A Practical Approach to the Management of Residual Cardiovascular Risk: United Arab Emirates Expert Consensus Panel on the Evidence for Icosapent Ethyl and Omega-3 Fatty Acids.

PURPOSE: Patients with hyperlipidemia treated with statins remain at a residual cardiovascular (CV) risk. Omega-3 polyunsaturated fatty acids hold the potential to mitigate the residual CV risk in statin-treated patients, with persistently elevated triglyceride (TG) levels. METHOD: We reviewed the current evidence on the use of icosapent ethyl (IPE), an omega-3 fatty acid yielding a pure form of eicosapentaenoic acid. RESULTS: REDUCE-IT reported a significant 25% reduction in CV events, including the need for coronary revascularization, the risk of fatal/nonfatal myocardial infarction, stroke, hospitalization for unstable angina, and CV death in patients on IPE, unseen with other omega-3 fatty acids treatments. IPE was effective in all patients regardless of baseline CV risk enhancers (TG levels, type-2 diabetes status, weight status, prior revascularization, or renal function). Adverse events (atrial fibrillation/flutter) related to IPE have occurred mostly in patients with prior atrial fibrillation. Yet, the net clinical benefit largely exceeded potential risks. The combination with other omega-3 polyunsaturated fatty acids, in particular DHA, eliminated the effect of EPA alone, as reported in the STRENGTH and OMEMI trials. Adding IPE to statin treatment seems to be cost-effective, especially in the context of secondary prevention of CVD, decreasing CV event frequency and subsequently the use of healthcare resources. CONCLUSION: Importantly, IPE has been endorsed by 20 international medical societies as a statin add-on treatment in patients with dyslipidemia and high CV risk. Robust medical evidence supports IPE as a pillar in the management of dyslipidemia.

Outcomes of Transcatheter Aortic Valve Replacement in the United Arab Emirates: Real-world, Single-centre Experience from an Emerging Programme.

Background: Data on outcomes of transcatheter aortic valve replacement (TAVR) in the Middle East, particularly in the United Arab Emirates (UAE), are limited. Whether centres with a low volume of patients requiring the procedure can achieve similar outcomes as those reported in pivotal clinical trials remains unclear. This study evaluates procedural outcomes of patients undergoing TAVR in a newly established programme in the UAE. Methods: Procedural outcomes of consecutive patients who underwent transfemoral TAVR at a single centre in the UAE between January 2016 and November 2021 were compared with those at centres in the lowest quartile (Q1) of procedural volume in the Transcatheter Valve Therapy Registry, which covers centres in the US. Results: Among the 183 patients included in the study, the median age was 76 years (interquartile range [IQR] 71-82), and 42.1% of patients were women, with a median Society of Thoracic Surgeons predicted risk of mortality score of 4.6 (IQR 2.9-7.5). Most of the patients (93.3%) received a balloon-expandable valve. All-cause death within 30 days, stroke and major vascular complications occurred in 0.6%, 0.6% and 2.2% of patients, respectively, compared with 3.1%, 2.2% and 4% in patients treated at Q1 hospitals. Conclusion: Patients undergoing transfemoral TAVR at an emerging centre in the Middle East had favourable outcomes compared with those performed at Q1 hospitals in the US. These findings suggest that careful patient selection for TAVR is critical and may help optimise patient outcomes, especially when procedural volumes are low.

Utilization of wild Cressa cretica biomass for pectinase production from a halo-thermotolerant bacterium.

Halophytes are the native inhabitants of saline environment. Their biomass can be considered as a potential substrate for the production of microbial enzymes. This study was intended at feasible utilization of a halophytic biomass, Cressia cretica, for pectinase production using a halo- and thermo-tolerant bacterium, Bacillus vallismortis MH 10. The data from fractionation of the C. cretica biomass revealed presence of 17% pectin in this wild biomass. Seven different factors (temperature, agitation, pH, inoculum size, peptone concentration, substrate concentration, and incubation time) affecting pectinase production using C. cretica were assessed through a statistical tool, Plackett-Burman design. Consequently, two significant factors (incubation time and peptone concentration) were optimized using the central composite design. The strain produced 20 IU mL-1 of pectinase after 24 h under optimized conditions. The enzyme production kinetics data also confirmed that 24 h is the most suitable cultivation period for pectinase production. Fourier transform infrared spectroscopy and scanning electron microscopy of C. cretica biomass ascertained utilization of pectin and structural changes after fermentation. The purification of pectinase by using DEAE column yielded specific activity and purification fold of 88.26 IU mg-1 and 3.2, respectively. The purified pectinase had a molecular weight of >65 kDa. This study offers prospects of large-scale production of pectinase by halotolerant strain in the presence of economical and locally grown substrate that makes the enzyme valuable for various industrial operations.

Unveiling the genomic potential of a novel thermostable glycoside hydrolases producing Neobacillus sedimentimangrovi UE25.

Genetic and enzymatic potential of Neobacillus sedimentimangrovi has not been assembled to date. Here, we report a high-quality genome assembly of thermophilic bacterium Neobacillus sedimentimangrovi UE25 using Illumina Hi-seq 2500. The strain was isolated from a crocodile pond Manghopir, Karachi, Pakistan. QUAST quality parameters showed 37.75% GC content and exhibited the genome into 110 contigs, with a total size of 3,230,777 bases. Genome of N. sedimentimangrovi UE25 harbors phage mediated DNA through horizontal gene exchange from the phages, symbiotic and pathogenic bacteria. Most of the phage genome encodes for hypothetical proteins, protease, and phage assembly proteins. Gene clusters encoding the intrinsic resistance to glycopeptides, isoniazid, rifamycin, elfamycin, macrolide, aminoglycosides, tetracycline and fluoroquinolone were identified into the genome. Since, the strain has been reported for the production of many industrially important thermostable enzymes, therefore, the genomic data of thermostable enzymes might be helpful to employ this species in commercial sectors. Probing genes of multiple thermostable glycoside hydrolase enzymes especially xylanases of N. sedimentimangrovi UE25 showed genetic diversity among the genes and confer the industrial importance of this microorganism. Furthermore, the genome of N. sedimentimangrovi will greatly improve our understanding of its genetics and evolution.

Investigating the self-assembling of nicotinic hydrazide-based amphiphile into nano-range vesicles and its amphotericin B loading applications.

Most of the drugs are hydrophobic and have low water solubility, therefore posing issues in their absorption and bioavailability. Nonionic surfactants improve the solubility of hydrophobic drugs by entrapping them in their lipid bilayers. Two nonionic surfactants NODNH-16 and NODNH-18 are synthesized and characterized using different techniques i.e. EI-MS, 1H NMR, and FTIR. These newly synthesized surfactants were screened for blood hemolysis assay and cell toxicity studies using the NIH/3T3 cell line to assess their biocompatibility. Then amphotericin B was loaded into niosomal vesicles, and the drug entrapment efficiency of these surfactants was measured using UV-visible spectroscopy. The morphology of drug-loaded niosomes of synthesized surfactants was investigated using AFM, and their size, polydispersity, and zeta potential were measured with the Zetasizer instrument. Finally, a simulation study was performed to determine the pattern of self-assembly of the synthesized amphiphiles. Both synthesized nonionic surfactants showed good entrapment efficiency of 60.65 ± 2.12% and 68.45 ± 2.12%, respectively. It was also confirmed that both these synthesized nonionic surfactants were safe and biocompatible and showed less blood hemolysis (i.e. 21.13 ± 2.11% and 23.32 ± 2.45%) and higher 3T3 cells' viability at 150 µg/mL concentration as compared to Tween®-80. The antifungal potential of amphotericin B-loaded niosomes has been evaluated against unicellular multi-fungal species, which showed a promising potential for fungicidal activity. These results are substantiated by constructing a safe vehicle system for drug delivery.

Enzyme Profiling and Identification of Endophytic and Rhizospheric Bacteria Isolated from Arthrocnemum macrostachyum.

Endophytic and rhizospheric bacteria isolated from halophytic plants support their host to survive in hyper-saline soil. These bacteria are also known to produce various enzymes with potential industrial applications. In this study, the endophytic and rhizospheric bacteria were isolated from Arthrocnemum macrostachyum collected from Karachi, Pakistan, and their ability to produce various extracellular enzymes was assessed using commercial and natural substrates. In total, 11 bacterial strains were isolated (four endophytic; seven rhizospheric). Bacillus was found to be the most abundant genus (73%), followed by Glutamicibacter (27%). The isolates including Glutamicibacter endophyticus and Bacillus licheniformis are reported for the first time from A. macrostachyum. All of the isolates were capable of producing at least two of the five industrially important hydrolytic enzymes tested, i.e., xylanase, cellulase, amylase, pectinase, and lipase. Lipase production was found to be highest among the isolates, i.e., up to 18 IU mL-1. Although most of the isolates could grow at a wide range of temperatures (4-55 °C), pH (1-11), and salt concentrations (2-12%), under extreme conditions, very little growth was observed and the optimal growth was recorded between 2% and 6% NaCl, 25 and 45 °C, and 7 and 9 pH. Our results suggest that these isolates could be potential producers of enzymes with several biotechnological applications.

Thymol mitigates cadmium-induced behavioral and cognitive deficits by up-regulating hippocampal BDNF levels in rats.

Cadmium is a potent neurotoxin and induces adverse impact on brain function. Protective effects of monoterpenes on the CNS have been reported previously. The present study was designed to investigate the beneficial effect of thymol on cadmium-induced neurotoxicity. Rats were initially divided into 2 groups, vehicle control and thymol. Thymol (40mg/kg) was given orally for 14 days. Each group was subdivided into two groups (Vehicle control and Cadmium, Thymol and Thymol+Cadmium). Cadmium Chloride (5mg/kg) was given for last 3 days only to the groups assigned as Cadmium and Thymol+Cadmium. Behavioral parameters were assessed after 24h of last dose of cadmium. Brain sample were collected and BDNF was measured in hippocampus. The present study suggests that pre-administration of thymol provides a protective therapy against cadmium-induced intoxication by enhancing the brain BDNF levels and plasticity. Results further suggest that thymol not only ameliorates cadmium-induced learning and memory impairment but also reduced anxiety, motor incoordination and depression assessed by various behavioral tests. The study may provide a better apprehension of the neuroprotective role of thymol and highlighting its significance in the diet for human health particularly in cadmium intoxication.

Designing Functionally Substituted Pyridine-Carbohydrazides for Potent Antibacterial and Devouring Antifungal Effect on Multidrug Resistant (MDR) Strains.

The emergence of multidrug-resistant (MDR) pathogens and the gradual depletion of available antibiotics have exacerbated the need for novel antimicrobial agents with minimal toxicity. Herein, we report functionally substituted pyridine carbohydrazide with remarkable antimicrobial effect on multi-drug resistant strains. In the series, compound 6 had potent activity against four MDR strains of Candida spp., with minimum inhibitory concentration (MIC) values being in the range of 16-24 µg/mL and percentage inhibition up to 92.57%, which was exceptional when compared to broad-spectrum antifungal drug fluconazole (MIC = 20 µg/mL, 81.88% inhibition). Substitution of the octyl chain in 6 with a shorter butyl chain resulted in a significant anti-bacterial effect of 4 against Pseudomonas aeruginosa (ATCC 27853), the MIC value being 2-fold superior to the standard combination of ampicillin/cloxacillin. Time-kill kinetics assays were used to discern the efficacy and pharmacodynamics of the potent compounds. Further, hemolysis tests confirmed that both compounds had better safety profiles than the standard drugs. Besides, molecular docking simulations were used to further explore their mode of interaction with target proteins. Overall results suggest that these compounds have the potential to become promising antimicrobial drugs against MDR strains.

From Clinical Clues to Final Diagnosis: The Return of Detective Work to Clinical Medicine in Cardiac Amyloidosis.

Cardiac amyloidosis is frequently misdiagnosed, denying patients the opportunity for timely and appropriate management of the disease. The purpose of this review and case studies is to raise awareness of the diagnostic "red flags" associated with cardiac amyloidosis and the currently available non-invasive strategies for diagnosis. The review focuses on the identification of one of the two main types of cardiac amyloidosis, transthyretin amyloid cardiomyopathy, and non-invasive tools to distinguish this from light-chain amyloidosis. A diagnostic algorithm centered around the use of non-invasive imaging and laboratory analysis is presented. The algorithm generates four differential diagnoses for patients presenting with signs and symptoms consistent with cardiac amyloidosis. Case examples are presented, representing the four potential outcomes of diagnosis using the algorithm. The review provides a guide on how to recognize the often-overlooked presentations of this disease in clinical practice. Non-invasive imaging techniques and diagnostic tools that do not require the involvement of a specialty center have allowed for the improved diagnosis of cardiac amyloidosis. Timely diagnosis of this life-threatening disease is essential for optimal management and it is imperative that clinicians have a high index of suspicion for patients presenting with "red flag" symptoms.

Review Article--Clinical Overview of Myocardial Infarction Without Obstructive Coronary Artey Disease (MINOCA).

The term myocardial infarction with non-obstructive coronary arteries (MINOCA) applies to patients who have clinical evidence of AMI but coronary angiography reveals no coronary obstructions and an alternative diagnosis is not possible. It is a heterogenous group of disease. Its prognosis, predictors of mortality and optimum management is unclear. In this review, we present a disease overview for MINOCA including the clinical features, adopted definitions, prevalence, diagnosis, treatment, and prognosis.

Evaluation of heavy metal pollutants in salt and seawater under the influence of the Lyari River and potential health risk assessment.

Heavy metals intoxication through edible salt poses serious health hazards. The conducted research assessed the levels of heavy metals, health risks of salt samples, and the pollution index of seawater obtained from saltpans located at Sandpit, Karachi, Pakistan, which receive untreated effluents through the Lyari River. Seawater (n = 27) and salt samples (n = 27) were prepared for the detection of Al, Cd, Pb, Cr, Fe, Cu, Hg, Ni, As and Zn through atomic absorption spectroscopy, mean concentrations ± S.D. (mg/mL) were compared with the National Environmental Quality Standards, Pakistan. The levels of Cr (40.06 ± 0.21) were the highest followed by Fe (39.77 ± 0.08) > As (25.12 ± 0.21) > Ni > Pb > Al > Hg > Zn > Cd > Cu. In sea salt (Mean ± S·D mg/Kg), the Cr (47.79 ± 0.19), Fe (47.5 ± 0.15), As (30.62 ± 0.22), and Ni were redundant elements followed by Al > Pb > Hg > Zn > Cu > Cd. The water comprehensive pollution index was 1000 times greater than the critical values. The single factor pollution index was highest for Hg (1321), followed by Cr (40), Ni (36), Pb (32), Al (31.4), Cd (31.3), and As (25). Health risk assessment indices (from salt samples), including target hazard quotient (THQ) for As, Pb, Al, Hg, and Cr were two to six times higher than the noncarcinogenic THQ reference range. Similarly, the hazardous index indicated that salt was 20 times hazardous (HI = 20.29), and the carcinogenic rate index for the heavy metals i.e., Cd, As, Cr, and Ni was above the reference CR value i.e., 1 × 10-4. In conclusion, the experimental and theoretical approaches recommend that the use of contaminated salt may impart health hazards.

Surviving under pollution stress: Antibacterial and antifungal activities of the Oyster species (Magallana bilineata and Magallana cuttackensis).

Antibiotic effectively controls the bacterial and fungal infections. Pathogens developing multi-drug resistance are a global health concern, which necessitate developing new molecules to overcome the resistance dilemma. This study explores the intrinsic ability of marine oysters synthesizing bioactive compounds. The tissue extracts prepared in n-hexane from two oysters, Magallana bilineata and Magallana cuttackensis compared for broad spectral antimicrobial activates against the fungal, Gram positive and negative pathogens. Regardless, both the species tolerated the same pollution indices; the M. bilineata exhibits stronger antimicrobial activities as compared to M. cuttackensis. M. bilineata potentially inhibited the bacterial growth with minimal inhibitory concentration (0.75-20 µg/ml) and fungal pathogens (0.75-5 µg/ml) as compared to ciprofloxacin and miconazole. Inhibitory potential complimented with reduce bactericidal and fungicidal concentrations required to observed susceptible zone of inhibition (ZOI). The inhibition augmented with increased antimicrobial index (AMI) and total activity index (TAI) against the human pathogen than those of M. cuttackensis. It is widely acknowledged that there is a need to develop novel antimicrobial agents to minimize the threat of emerging multiple antimicrobial resistant pathogens. Therefore, the oysters surviving in the pollution stress modulate the physiological and immune response may exploit to develop potential antibiotics.

The unravelled Enterococcus faecalis zoonotic superbugs: Emerging multiple resistant and virulent lineages isolated from poultry environment.

This study aimed to investigate the zoonotic potential by virtue of phylogenetic analysis, virulence and resistance gene profiles of Enterococcus faecalis originating from poultry environment. The ERIC, BOX and RAPD PCR analysis showed the clustering of E. faecalis strains (n = 74) into five groups (G1-G5) and fifteen sub-clusters (B1-B15), which share 50%-80% similarities with ATCC E. faecalis and clinical strains of human infection. E. faecalis strains harboured seven enterocins genes including ent1097 (85%), entB (84%), enterolysinA (51%), entSEK4 (51%), entL50 (31%), entA (25.7%) and ent1071 (14.9%). The highest prevalence of gelE-sprE (90%), lip-fl (90%) followed by cylL (62%), hyl (60%), katA (16%) and cylA (5.4%) was observed in poultry isolates. The fsr operon and gelE-sprE was co-associated in 66.2% strains. E. faecalis also harboured biofilm and endocarditis-associated genes, including efaAfs (97%), ebp-pilli (ebpABC and srtC 69.9%-80%), asa1 (71%), agg (55%), ace (54%) and esp-Tim (3%). Despite all found sensitive to vancomycin, 98.6% strains were multi-drug resistant to five to twelve tested antimicrobials. An increased-level of resistance (≥32 µg/ml) was observed to ampicillin (8.1%), meropenem (21.6%), chloramphenicol (73.4%), erythromycin (90.5%), tetracycline (100%) and high-level resistance to kanamycin (79.7%) and gentamicin (52.7%). The multi-drug resistant E. faecalis (MDRe.f) were carried pbp4 (90%), tetL (90%), tetM (70%), ermB (81%), cat (52.7%), acc6-aph2 (58.1%), aaph(3)-III (49.9%), gyrA (97%) and parC (98%) genes. Moreover, these MDRe.f were also harboured, hospital-associated marker IS16 (58%) and pheromone responsive genes, that is ccf (88%), cpd (74%), cob (62%) and eep (66%). Thus, regardless of the distinct phylogenetic background of E. faecalis of poultry origin, ATCC E. faecalis and clinical strains of human origin, we found major similarities in virulence, resistance gene profiles and mobile genetic elements (IS16 and pheromone responsive plasmids), supporting the zoonotic/reverse zoonotic risk associated with this organism.

Prevalence and genetic profiling of tetracycline resistance (Tet-R) genes and transposable element (Tn916) in environmental Enterococcus species.

Resistance against antimicrobial agents in enterococci is a global concern that not only challenges infection therapy but also make them reservoir of antibiotic resistance in human and animal alike. This study was conducted to establish tetracycline resistance profiles, prevalence of tet genes and transposable element (Tn916) in enterococcal soil and clinical isolates. Enterococci (n = 1210) from different environmental niche were collected and subjected to molecular identification. In total, 361 isolates showed tetracycline resistance at the breakpoint of 32 µg ml-1. MICs (32-512 µg ml-1) were established by both agar and micro-broth dilution methods. Soil isolates (n = 76) were further investigated for Tet genes (tet-A, C, K, L, M, S, O) and Tn916. Major resistance was observed in E. faecium 67% followed by E. faecalis 22%, E. hirae 8% and E. casseliflavus 2.6%. Results revealed that tet(L) was more frequently found in E. faecium 74.5%, while tet(M) was in high prevalence in E. faecalis 82.3%. Tn916 was detected in both clinical and soil isolates (i.e. 43.3% and 19.7%, respectively). RAPD-PCR analysis showed high diversity among the investigated isolates. Cumulatively, our results revealed high-level tetracycline resistance and the presence of multiple Tet genes and transposable element Tn916 in enterococci.

Molecular assessment of virulence determinants, hospital associated marker (IS16gene) and prevalence of antibiotic resistance in soil borne Enterococcus species.

Enterococci, no more regarded as GRAS (Generally Recognized As Safe) organism, are emerging as an important source of nosocomial infections worldwide. The main contributors in pathogenesis of enterococci are the presence of various virulent factors and antibiotic resistance genes. We aimed to examine the prevalence, dissemination, antibiotic resistance and virulent factors associated with enterococci from bulk soil (BS). A total of 372 enterococci were isolated from 500 soil samples. PCR was used to identify the isolates up to species level and for carriage of 16 virulence genes including hospital associated marker (i.e. IS16). E. faecium (77%), E. faecalis (10%), E. hirae (4%) and E. casseliflavus (1%) were the major species isolated. The efaAfs was the most dominant gene (100%), followed by gelE (78.9%), sprE (76.3%) and esp (13%) in E. faecalis isolates. The E. faecium carried largely efaAfm (86.8%) and acm (50.3%) genes. Presence of entP (10%), entA (8.3%) and entB (6.9%) genes was detected mostly in E. faecium, while enlA (18%) and ef1097 (2.6%) was only detected in E. faecalis isolates. 50% E. faecalis and 2% E. faecium isolates harbored IS16, while five E. faecalis harbored both IS16 and espTIM genes providing strong evidence about the presence of espTIM gene on 64 Kb pathogenicity island. BOX and RAPD PCR analysis revealed high degree of genetic variation within the species. Degree of resistance against 12 major antibiotics showed chloramphenicol as the most effective and meropenom as the least effective antibiotic. Presence of multiple antibiotic resistant, virulent and hospital associated enterococci in bulk soil represents a potential source for further dissemination to humans and animals and poses potential impact on public health.

Ionic strength effects on the photodegradation reactions of riboflavin in aqueous solution.

A study of the effect of ionic strength on the photodegradation reactions (photoreduction and photoaddition) of riboflavin (RF) in phosphate buffer (pH7.0) has been carried out using a specific multicomponent spectrometric method. It has been found that the rates of photodegradation reactions of RF are dependent upon the ionic strength of the solutions at different buffer concentrations. The apparent first-order rate constants (kobs) for the photodegradation of riboflavin at ionic strengths of 0.1-0.5 (0.5M phosphate) lie in the range of 7.35-30.32 × 10(-3) min(-1). Under these conditions, the rate constants for the formation of the major products, lumichrome (LC) by photoreduction pathway, and cyclodehydroriboflavin (CDRF) by photoaddition pathway, are in the range of 3.80-16.03 and 1.70-6.07 × 10(-3) min(-1), respectively. A linear relationship has been observed between log kobs and √µ/1+√µ. A similar plot of log k/ko against √µ yields a straight line with a value of ~+1 for ZAZB showing the involvement of a charged species in the rate determining step. NaCl appears to promote the photodegradation reactions of RF probably by an excited state interaction. The implications of ionic strength on RF photodegradation by different pathways and flavin-protein interactions have been discussed.

Anaesthesia in various anterior segment complications of sub-Tenon surgeries.

OBJECTIVE: The sub-Tenon's space is a potential space between the capsule and the sclera. This study evaluated complications from sub-Tenon's anaesthesia in different corneal and anterior chamber ophthalmic surgical procedures. METHODS: The prospective cross-sectional study was carried out at the Baqai Medical University, Karachi, from March 2010 to August 2011, and comprised 149 patients for various minor and major intraocular surgeries. All the patients were operated under sub-Tenon's anaesthesia, administered in the inferio-nasal quadrant with a 19G cannula.Their complications were noted on a specific proforma. Data was analysed for frequencies of complications. SPSS 13 was used for statistical analysis. RESULTS: There were 82 (55%) males and 67 (45%) females who underwent surgery. There were 89 (59.7%) right eyes and 60 (40%) left eyes. The commonest surgery was phaco-emulsification (n = 79; 53%), followed by extracapsular cataract extraction with intraocular lens implantation (n = 33; 22.1%). Subconjuctival haemorrhage (n = 75; 50.3%) was the commonest complication, and the least common was pain during injection (n = 9; 6%). CONCLUSION: There was no incidence of life-threatening or sight-threatening complications. The procedure was almost pain free and can be simply, safely and effectively given by the beginners with due precautions.