Nano-microbial based technology employing polyvalent phage conjugate: A next generation weapon for antimicrobial resistance lurking behind wastewater

Worldwide, due to a dearth of innovative interventions, new forms of antimicrobial resistance (AMR) are being discovered every day in clinical and environmental settings. Therefore, it is necessary to remove these contaminants directly or indirectly from the environment. Nanomicrobial-based technology employing nanomaterials with microbes is a new paradigm that finds a place in the antimicrobial crisis. Microbial entities such as phages can be used to treat antimicrobial resistance, but phage resistance is challenging and limits its applicability. Similarly, nanotechnology will not be able to selectively remove resistant strains from the environment individually. Therefore, we employ nanomicrobial-based technology that aims to fill these gaps. In the present study, polyvalent phages were isolated from wastewater with an easy-to-use modified multi-host sequential approach, characterized and conjugated with magnetite (Fe₃O₄) nanoparticles with the modified formulation to form nanomicrobial conjugates (NMCs). These NMCs were subjected to characterization and in vitro antibacterial studies. The results indicated a significant polyvalency of phages in the order of Caudovirales. Transmission electron microscopy (TEM) analysis of Fe₃O₄ nanoparticles formed by the co-precipitation method showed a particle size of 30 ± 5 nm and the selected area electron diffraction (SAED) pattern indicates a single-phase crystalline structure. To form NMCs, isolated phages (10⁵ PFU/mL) were immobilized onto Fe₃O₄ nanoparticles. Further, surface modification of Fe₃O₄ nanoparticles enables the covalent association of phages. Biosurfactant-functionalized Fe₃O₄ nanoparticles (FNMCs) were found to have higher phage loading capacity, with a significant value of p < 0.0127 and a zeta potential of -22.2 mV. TEM studies and in vitro biofilm assay showed that NMCs exhibit promising antibacterial activity against various resistant bacterial strains. Pilot studies showed that NMCs can selectively eliminate up to 98.3% of AMR in wastewater. Thus, these findings indicate a synergistic effect of both phage and nanomaterial and this technology is expected to be a new lead in wastewater management.

A Pragmatic Scoring Tool to Predict Hydroxyurea Response Among β-Thalassemia Major Patients in Pakistan

Despite high prevalence and incidence of β-thalassemia in Pakistan, there is very limited work on the use of hydroxyurea (HU) in thalassemia patients in the country. This is the first insight regarding genetic profiling of BCL11A and HU responses in Pakistani β-thalassemia. It correlates single-nucleotide polymorphisms on BCL11A (rs4671393, rs766432) and HBG2 (XmnI), age at first transfusion, and β-globin mutations with HU response in β-thalassemia major (BTM). Of 272 patients treated with HU, 98 were complete responders, 55 partial responders, and 119 nonresponders. Our analysis shows that HU response was significantly associated with patients having IVSI-1 or CD 30 mutation (P<0.001), age at first transfusion >1 year (P<0.001), and with the presence of XmnI polymorphism (P<0.001). The single-nucleotide polymorphisms of BCL11A were more prevalent among responders, but could not show significant association with HU response (P>0.05). Cumulative effect of all 5 predicting factors through simple binary scoring indicates that the likelihood of HU response increases with the number of primary and secondary genetic modifiers (P<0.001). Predictors scoring is a pragmatic tool to foresee HU response in patients with BTM. The authors recommend a score of ≥2 for starting HU therapy in Pakistani patients with BTM.

Cyanobacteria as Natural Therapeutics and Pharmaceutical Potential: Role in Antitumor Activity and as Nanovectors

Cyanobacteria (blue-green microalgae) are ubiquitous, Gram-negative photoautotrophic prokaryotes. They are considered as one of the most efficient sources of bioactive secondary metabolites. More than 50% of cyanobacteria are cultivated on commercial platforms to extract bioactive compounds, which have bene shown to possess anticancer activity. The chemically diverse natural compounds or their analogues induce cytotoxicity and potentially kill a variety of cancer cells via the induction of apoptosis, or altering the activation of cell signaling, involving especially the protein kinase-C family members, cell cycle arrest, mitochondrial dysfunctions and oxidative damage. These therapeutic properties enable their use in the pharma and healthcare sectors for the betterment of future generations. This review provides a baseline overview of the anti-cancerous cyanobacterial bioactive compounds, along with recently introduced nanomaterials that could be used for the development of new anticancer drugs to build a healthy future for mankind.

Green Synthesis, Characterization and Antimicrobial Activity of Copper Oxide Nanomaterial Derived from Momordica charantia

Background

In the emerging field of nanotechnology, copper oxide (CuO) nanomaterials are considered to be one of the most important transition metal oxides owing to its fascinating properties. Its synthesis from green chemistry principles is gaining importance as next-generation antibiotics due to its simplicity, eco-friendliness, and cost-effectiveness. In the present study, CuO nanorods (CuO NRs) were synthesized from the aqueous fruit extract of Momordica charantia and characterized using different analytical techniques. Further, the biomedical therapeutic potential was evaluated against multi-drug resistant microbial strains.

Materials and Methods

To synthesize CuO NRs, 0.1M of CuSO₄.5H₂O solution was added to aqueous extract of Momordica charantia in a 1:3 (v/v) ratio (pH=11) and heated at 50°C followed by washing and drying. The synthesized CuO NRs were subjected to characterization using different analytical techniques such as UV visible spectroscopy, zeta sizer equipped with zeta potential, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM). Further, the application as a biomedical therapeutic potential was evaluated in vitro using well diffusion method against eleven multidrug-resistant clinical bacterial strains, a fungus- Trichophyton rubrum and in ovo against the R₂B virus using haemagglutination (HA) test.

Results

Characterization was preliminarily done by the spectral study that confirms the absorbance band at 245nm. FTIR analysis at 628 cm⁻¹ peak identified copper oxide vibration. SEM analysis revealed agglomerated particle clusters. However, with TEM clear nanorods of average diameter of 61.48 ± 2 nm were observed. EDAX confirmed CuO formation while XRD showed a typical monoclinic structure with 6 nm crystallite size. Biological screening of CuO NRs showed significant results against both in vitro and in ovo methods. Significant inhibitory activity (p<0.0001) was noted against most of the resistant human pathogenic strains including both Gram-positive and Gram-negative bacteria. The highest efficacy was observed against Bacillus cereus with a 31.66 mm zone of inhibition. Besides, the therapeutic potential of CuO NRs against Corynebacterium xerosis, Streptococcus viridians and R₂B strain of Newcastle disease is reported for the first time.

Conclusion

Based on the present results, it could be expected that green synthesized CuO NRs would find potential applications in the field of nanomedicine.

A Model to Identify Sarcopenia in Patients With Cirrhosis

BACKGROUND & AIMS

The severe depletion of muscle mass at the third lumbar vertebral level (sarcopenia) is a marker of malnutrition and is independently associated with mortality in patients with cirrhosis. Instead of monitoring sarcopenia by cross-sectional imaging, we investigated whether ultrasound-based measurements of peripheral muscle mass, measures of muscle function, along with nutritional factors, are associated with severe loss of muscle mass.

METHODS

We performed a prospective study of 159 outpatients with cirrhosis (56% male; mean age, 58 ± 10 years; mean model for end-stage liver disease score, 10 ± 3; 60% Child-Pugh class A) evaluated at the Cirrhosis Care Clinic at the University of Alberta Hospital from March 2011 through September 2012. Lumbar skeletal muscle indices were determined by computed tomography or magnetic resonance imaging. We collected clinical data and data on patients' body composition, nutrition, and thigh muscle thickness (using ultrasound analysis). We also measured mid-arm muscle circumference, mid-arm circumference, hand grip, body mass index, and serum level of albumin; patients were evaluated using the subjective global assessment scale. Findings from these analyses were compared with those from cross-sectional imaging, for each sex, using logistic regression analysis.

RESULTS

Based on cross-sectional imaging analysis, 43% of patients had sarcopenia (57% of men and 25% of women). Results from the subjective global assessment, serum level of albumin, and most nutritional factors were significantly associated with sarcopenia. We used multivariate analysis to develop a model to identify patients with sarcopenia, and developed a nomogram based on body mass index and thigh muscle thickness for patients of each sex. Our model identified men with sarcopenia with an area under the receiver operating characteristic curve value of 0.78 and women with sarcopenia with an area under the receiver operating characteristic curve value of 0.89.

CONCLUSIONS

In a prospective study of patients with cirrhosis, we found that the combination of body mass index and thigh muscle thickness (measured by ultrasound) can identify male and female patients with sarcopenia almost as well as cross-sectional imaging (area under the receiver operating characteristic curve values of 0.78 and 0.89, respectively). These factors might be used in screening and routine nutritional monitoring of patients with cirrhosis.

The 22/11 risk prediction model: a validated model for predicting 30-day mortality in patients with cirrhosis and spontaneous bacterial peritonitis

OBJECTIVES

Clinicians do not have a validated tool for estimating the short-term mortality associated with spontaneous bacterial peritonitis (SBP). Accurate prognosis assessment is important for risk stratification and for individualizing therapy. We aimed therefore to develop and validate a model for the prediction of 30-day mortality in SBP patients receiving standard medical treatment (antibiotics and if indicated by guidelines, intravenous albumin therapy).

METHODS

We retrospectively identified SBP patients treated at a tertiary care center between 2003 and 2011 (training set). Multivariate regression modeling and receiver operating characteristic (ROC) curves were utilized for statistical analysis. An external data set of 109 SBP patients was utilized for validation.

RESULTS

Of the 184 patients in the training set, 66% were men with a median age of 55 years, a median MELD (Model for End-Stage Liver Disease) score of 20, and a 30-day mortality of 27%. Peripheral blood leukocyte count ≥11×10⁹ cells/l (odds ratio (OR) 2.5; 95% confidence interval CI: 1.2-5.2) and MELD score ≥22 (OR 4.6; 95% CI: 2.3-9.6) were independent predictors of 30-day mortality. Patients with neither, one, or both variables had 30-day mortality rates of 8%, 32%, and 52%, respectively. The findings in the validation set mirrored the training set.

CONCLUSIONS

In cirrhotic patients with SBP receiving standard therapy, MELD score ≥22 and peripheral blood leukocyte count ≥11×10⁹ cells/l are validated independent predictors of mortality. The mortality in a patient without either poor prognostic variable is ≤10% and with both variables is ≥50%. Trials aiming to reduce mortality should target patients in the moderate-risk to high-risk groups.