Drug resistance profile and biofilm forming potential of Pseudomonas aeruginosa isolated from contact lenses in Karachi-Pakistan

BACKGROUND: The contaminated contact lens provides Pseudomonas aeruginosa an ideal site for attachment and biofilm production. Continuous contact of the eye to the biofilm-infested lens can lead to serious ocular diseases, such as keratitis (corneal ulcers). The biofilms also prevent effective penetration of the antibiotics, which increase the chances of antibiotic resistance. METHODS: For this study, 22 Pseudomonas aeruginosa isolates were obtained from 36 contact lenses and 14 contact lens protective fluid samples. These isolates were tested against eight commonly used antibiotics using Kirby-Bauer disk diffusion method. The biofilm forming potential of these isolates was also evaluated using various qualitative and quantitative techniques. Finally, a relationship between biofilm formation and antibiotic resistance was also examined. RESULTS: The isolates of Pseudomonas aeruginosa tested were found resistant to most of the antibiotics tested. Qualitative and quantitative biofilm analysis revealed that most of the isolates exhibited strong biofilm production. The biofilm production was significantly higher in isolates that were multi-drug resistant (p < 0.0001). CONCLUSION: Our study indicates that multi-drug resistant, biofilm forming Pseudomonas aeruginosa isolates are mainly involved in contact lens associated infections. This appears to be the first report from Pakistan, which analyzes both antibiotic resistance profile and biofilm forming potential of Pseudomonas aeruginosa isolates from contact lens of the patients with contact lens associated infections

Living bioethics, clinical ethics committees and children's consent to heart surgery

This discussion paper considers how seldom recognised theories influence clinical ethics committees. A companion paper examined four major theories in social science: positivism, interpretivism, critical theory and functionalism, which can encourage legalistic ethics theories or practical living bioethics, which aims for theory–practice congruence. This paper develops the legalistic or living bioethics themes by relating the four theories to clinical ethics committee members’ reported aims and practices and approaches towards efficiency, power, intimidation, justice, equality and children’s interests and rights. Different approaches to framing ethical questions are also considered. Being aware of the four theories’ influence can help when seeking to understand and possibly change clinical ethics committee routines. The paper is not a research report but is informed by a recent study in two London paediatric cardiac units. Forty-five practitioners and related experts were interviewed, including eight members of ethics committees, about the work of informing, preparing and supporting families during the extended process of consent to children’s elective heart surgery. The mosaic of multidisciplinary teamwork is reported in a series of papers about each profession, including this one on bioethics and law and clinical ethics committees’ influence on clinical practice. The qualitative social research was funded by the British Heart Foundation, in order that more may be known about the perioperative views and needs of all concerned. Questions included how disputes can be avoided, how high ethical standards and respectful cooperation between staff and families can be encouraged, and how minors’ consent or refusal may be respected, with the support of clinical ethics committees

Comparative assessment of haematological profile in hatchery and riverine populations of Channa marulius

798-803Present study was conducted to assess the haematological profile of Channa marulius from hatchery and riverine populations. Blood samples were collected by caudal vein puncture. Significantly higher values (p ≤ 0.05) were recorded for various blood indices in hatchery populations as compared to those of riverine sources. Observed values of haematological parameters in hatchery populations were: Erythrocytes 4.90×106 cells µL-1, eosinophils 4.06 %, monocytes 5.53 %, haematocrit count 28.86 %, haemoglobin content 5.385 gdL-1, platelet distribution width 6.91 fL, red blood cell distribution width 23.83 fL, Procalcitonin 2.37 µL, mean corpuscular volume 7.87 fL and large platelet concentration ratio 14.64 %. In riverine populations, significantly higher values (p ≤ 0.05) for leucocytes count 5625×103 µL-1, mean cell haemoglobin 32.75 pg, mean corpuscular haemoglobin concentration 43.66 gdL-1 and mean cell volume 171.90 fL were observed as compared to those of hatchery populations. Conversely, non-significant (p ≥ 0.05) differences were observed with elevated values for neutrophils (14.042 %) in riverine fish populations as compared hatchery samples (13.896 %). Lymphocytes and platelets counts were 17.344 % and 33.742×103 µL-1, respectively in hatchery populations whereas in riverine populations these were 13.764 % and 33.896×103 µL-1, respectively. Physico-chemical parameters of sample water were observed to be in safe range throughout the study period. The observed variation in haematological profile between both groups is due to different inhabiting conditions that exert direct impacts on fish haematology

Partial characterization of glutathione S-transferase (GST) isolated from hepatocytes of Cyprinus carpio from river Ravi Punjab, Pakistan

1017-1024Glutathione S-transferase (GST) is vital in oxidative stress. Keeping in view the importance of this enzyme, present study was conducted for partial characterization of GST from hepatocytes of Cyprinus carpio. The inferences showed higher (GST) activity in liver of C. carpio collected from Chashma Barrage (144.33±1.15) as compared to Trimmu Head works (128.66.3±0.577) and Rasul Barrage (111.66±0.577) sampling sites. The highest GST activity was 128±0.333 U mL-1 from the crude extract fraction of liver as compared to other fractions of appraisal fish liver. Whereas the lowest activity (109±0.666 U mL-1) was from desalted fraction. Optical density was recorded by spectrophotometer at 280 nm, the fractions that showed high optical density were subjected to enzyme assay. Highest specific activity was 183.63, 153.84 and 162.50 U mg-1 for purified liver GST of C. carpio captured from Trimmu Head works, Rasul Barrage and Chashma Barrage, respectively. Whereas, fold purification was 2.86, 2.69 and 2.10 while, percent recovery was 78.90, 72.07 and 63.19 %, respectively for purified liver GST. The optimum pH was 6.5, 6.0 and 6.8 whereas, temperature was 30.5 oC, 31 oC and 30 oC followed by substrate concentration 40.3 mM, 40 mM and 41 mM, for purified liver GST of C. carpio captured from Trimmu Head works, Rasul Barrage and Chashma Barrage, respectively. It should be noted that detailed studies can be beneficial in the fields of physiology, biochemistry and toxicology

Haptoglobin genotype and outcome after spontaneous intracerebral haemorrhage

OBJECTIVE: Haptoglobin is a haemoglobin-scavenging protein that binds and neutralises free haemoglobin and modulates inflammation and endothelial progenitor cell function. A HP gene copy number variation (CNV) generates HP1 and HP2 alleles, while the single-nucleotide polymorphism rs2000999 influences their levels. The HP1 allele is hypothesised to improve outcome after spontaneous (non-traumatic) intracerebral haemorrhage (ICH). We investigated the associations of the HP CNV genotype and rs2000999 with haematoma volume, perihaematomal oedema (PHO) volume, functional outcome and mortality after ICH. METHODS: We included patients with neuroimaging-proven ICH, available DNA and 6-month follow-up in an observational cohort study (CROMIS-2). We classified patients into three groups according to the HP CNV: 1-1, 2-1 or 2-2 and also dichotomised HP into HP1-containing genotypes (HP1-1 and HP2-1) and HP2-2 to evaluate the HP1 allele. We measured ICH and PHO volume on CT; PHO was measured by oedema extension distance. Functional outcome was assessed by modified Rankin score (unfavourable outcome defined as mRS 3-6). RESULTS: We included 731 patients (mean age 73.4, 43.5% female). Distribution of HP CNV genotype was: HP1-1 n=132 (18.1%); HP2-1 n=342 (46.8%); and HP2-2 n=257 (35.2%). In the multivariable model mortality comparisons between HP groups, HP2-2 as reference, were as follows: OR HP1-1 0.73, 95% CI 0.34 to 1.56 (p value=0.41) and OR HP2-1 0.5, 95% CI 0.28 to 0.89 (p value=0.02) (overall p value=0.06). We found no evidence of association of HP CNV or rs200999 with functional outcome, ICH volume or PHO volume. CONCLUSION: The HP2-1 genotype might be associated with lower 6-month mortality after ICH; this finding merits further study

A semiparametric modeling framework for potential biomarker discovery and the development of metabonomic profiles

<p>Abstract</p> <p>Background</p> <p>The discovery of biomarkers is an important step towards the development of criteria for early diagnosis of disease status. Recently electrospray ionization (ESI) and matrix assisted laser desorption (MALDI) time-of-flight (TOF) mass spectrometry have been used to identify biomarkers both in proteomics and metabonomics studies. Data sets generated from such studies are generally very large in size and thus require the use of sophisticated statistical techniques to glean useful information. Most recent attempts to process these types of data model each compound's intensity either discretely by positional (mass to charge ratio) clustering or through each compounds' own intensity distribution. Traditionally data processing steps such as noise removal, background elimination and m/z alignment, are generally carried out separately resulting in unsatisfactory propagation of signals in the final model.</p> <p>Results</p> <p>In the present study a novel semi-parametric approach has been developed to distinguish urinary metabolic profiles in a group of traumatic patients from those of a control group consisting of normal individuals. Data sets obtained from the replicates of a single subject were used to develop a functional profile through Dirichlet mixture of beta distribution. This functional profile is flexible enough to accommodate variability of the instrument and the inherent variability of each individual, thus simultaneously addressing different sources of systematic error. To address instrument variability, all data sets were analyzed in replicate, an important issue ignored by most studies in the past. Different model comparisons were performed to select the best model for each subject. The m/z values in the window of the irregular pattern are then further recommended for possible biomarker discovery.</p> <p>Conclusion</p> <p>To the best of our knowledge this is the very first attempt to model the physical process behind the time-of flight mass spectrometry. Most of the state of the art techniques does not take these physical principles in consideration while modeling such data. The proposed modeling process will apply as long as the basic physical principle presented in this paper is valid. Notably we have confined our present work mostly within the modeling aspect. Nevertheless clinical validation of our recommended list of potential biomarkers will be required. Hence, we have termed our modeling approach as a "framework" for further work.</p

Prevalence of asymptomatic leishmania infection in people living with HIV and progression to symptomatic visceral leishmaniasis in Bihar, India

Intro People living with HIV (PLHIV) have an increased risk of developing visceral leishmaniasis (VL) and poor outcomes compared to HIV-negative individuals. Here, we aim to establish the prevalence and determinants of asymptomatic Leishmania infection (ALI) and the rate and risk factors for progression of ALI to VL in a cohort of PLHIV in Bihar, India. Methods We conducted a cross-sectional survey of PLHIV ≥18 years of age with no history or current diagnosis of VL or PKDL at anti-retroviral therapy centres within VL endemic districts of Bihar. ALI was defined as a positive rK39 ELISA, rK39 RDT, and/or qPCR. Additionally, the urinary Leishmania antigen ELISA was evaluated. The ALI and non-ALI cohorts were followed up every three months for 18 months in person and by telephone, respectively. Determinants for ALI were established using logistic regression model. Findings A total of 1,296 PLHIV enrolled in HIV care, 694 (53.6%) of whom were female and a median age of 39 years (IQR 33–46), were included in the analysis. The baseline prevalence of ALI was 7.4% (n=96). All 96 individuals were positive by rK39 ELISA, while 0.5% (n=6) and 0.4% (n=5) were positive by qPCR and rK39 RDT, respectively. Risk factors for ALI were CD4 counts <100 (OR 3.1; 95%CI 1.2–7.6) and CD4 counts 100-199 (OR=2.1; 95% CI: 1.1-4.0) compared to CD4 counts ≥300, and a household size ≥5 (OR=1.9; 95%CI: 1.1-3.1).Within the ALI cohort, four (3.7%) participants developed VL, compared to no progression in the non-ALI cohort. Mortality rates were higher in ALI compared to non-ALI (OR =2.7; 95% CI: 1.1-6.1). Conclusion The prevalence of ALI in PLHIV in VL endemic villages in Bihar was relatively high. However, the progression rate from ALI to VL in PLHIV was low. Patients with low CD4 counts and larger household size were at higher risk of ALI

Autologous haematopoietic stem cell transplantation and other cellular therapy in multiple sclerosis and immune-mediated neurological diseases : updated guidelines and recommendations from the EBMT autoimmune diseases working party (ADWP) and the joint accreditation committee of EBMT and ISCT (JACIE)

These updated EBMT guidelines review the clinical evidence, registry activity and mechanisms of action of haematopoietic stem cell transplantation (HSCT) in multiple sclerosis (MS) and other immune-mediated neurological diseases and provide recommendations for patient selection, transplant technique, follow-up and future development. The major focus is on autologous HSCT (aHSCT), used in MS for over two decades and currently the fastest growing indication for this treatment in Europe, with increasing evidence to support its use in highly active relapsing remitting MS failing to respond to disease modifying therapies. aHSCT may have a potential role in the treatment of the progressive forms of MS with a significant inflammatory component and other immune-mediated neurological diseases, including chronic inflammatory demyelinating polyneuropathy, neuromyelitis optica, myasthenia gravis and stiff person syndrome. Allogeneic HSCT should only be considered where potential risks are justified. Compared with other immunomodulatory treatments, HSCT is associated with greater short-term risks and requires close interspeciality collaboration between transplant physicians and neurologists with a special interest in these neurological conditions before, during and after treatment in accredited HSCT centres. Other experimental cell therapies are developmental for these diseases and patients should only be treated on clinical trials