Characterization of a Coliphage AS1 isolated from sewage effluent in Pakistan

The emergence of multi-drug resistant (MDR) bacterial strains, which are posing a global health threat has developed the interest of scientists to use bacteriophages instead of conventional antibiotics therapy. In light of an increased interest in the use of phage as a bacterial control agent, the study aimed to isolate and characterize lytic phages from sewage effluent. During the current study, bacteriophage AS1 was isolated from sewage effluent against E.coli S2. The lytic activity of phageAS1 was limited to E.coli S2 strain showing monovalent behavior. The calculated phage titer was 3.5×109 pfu/ml. PhageAS1 was stable at a wide range of pH and temperature. The maximum stability was recorded at 37ºC and pH 7.0, while showing its normal lytic activity at temperature 60ºC and from pH 5.0 to11.0 respectively. At temperature 70ºC, phage activity was somewhat reduced whereas, further increase in temperature and decrease or increase in pH completely inactivated the phage. From the current study, it was concluded that waste water is a best source for finding bacteriophages against multi-drug resistant bacterial strains and can be used as bacterial control agent.

Bioaccumulation of heavy metals in the tissues of Schizothorax plagiostomus at River Swat

Snow trout (Schizothorax plagiostomus) is an economically important freshwater fish, mostly found in northern areas of water reservoirs of Pakistan. The current study was conducted in River Swat to analyze the bioaccumulation of heavy metals (Pb, Cr, Ni, and Zn) in tissues of Schizothorax plagiostomus. Tissues were extracted and dissolved in perchloric acid (HClO4) and nitric acid (HNO3) along with hotplate. The heavy metals, zinc (Zn), lead (Pb), chromium (Cr), and Nickel (Ni) were determined using Perkin Elmer 2380 atomic absorption spectrophotometer. Results shows great variation in the content of the metal related to tissue type and sampling sites. A high concentration of bioaccumulation was reported at Charbagh, whereas lowest at Odigram: Charbagh>Landakai>Odigram. In the same way, Cr was the most accumulated heavy metal followed by lead, nickel, and Zinc.

Spectroscopic evaluation of vibrational temperature and electron density in reduced pressure radio frequency nitrogen plasma

Abstract

The optical emission spectroscopy technique is used to determine the vibrational temperature of the second positive band system,$$ N_{2} (C,\upsilon^{^{\prime}} - B,\upsilon^{^{\prime\prime}}$$ N 2 ( C , υ ′ - B , υ ″ ) in the wavelength range 367.1–380.5 nm by using the line-ratio and Boltzmann plot methods. The electron temperature is evaluated from the intensity ratio of the selected molecular bands corresponding to $$N_{2}^{ + } (B,\upsilon - X, \upsilon^{^{\prime}} , $$ N 2 + ( B , υ - X , υ ′ , 391.44 nm), and, $$N_{2} (C,\upsilon^{^{\prime}} - B,\upsilon^{^{\prime\prime}}$$ N 2 ( C , υ ′ - B , υ ″ , 375.4 nm) transitions, respectively. The selected bands have a different threshold of excitation energies and thus serve as a sensitive indicator of the electron energy distribution function (EEDF). The electron density has been determined from the intensity ratio of the molecular transitions corresponding to $$N_{2}^{ + } (B,\upsilon - X, \upsilon^{^{\prime}} , $$ N 2 + ( B , υ - X , υ ′ , 391.44 nm), and, $$ N_{2} (C,\upsilon^{^{\prime}} - B,\upsilon^{^{\prime\prime}}$$ N 2 ( C , υ ′ - B , υ ″ , 380.5 nm) for different levels of pressure and radio frequency power. The results show that the vibrational temperature decreases with increasing nitrogen fill pressure and radio frequency power. However, the electron temperature increases with radio frequency power and reduces with fill pressure. The electron density increases both with nitrogen fill pressure and radio frequency power that attributes to the effective collisional transfer of energy producing electron impact ionization. Plasma parameters show a significant dependence on discharge conditions and can be fine-tuned for specific surface treatments.

Article Highlights

Comparative brain analysis of wild and hatchery reared Mahseer (Tor putitora) relative to their body weight and length

The present study was aimed at comparing the brain size of mahseer (Tor putitora) in relation to their body weight and standard length, to investigate the potential impact of rearing environment on brain development in fish. The weight of the brain and three of its subdivisions cerebellum (CB), optic tectum (OT), and telencephalon (TC) were measured for both wild and hatchery-reared fish. The data was analysed using multiple analysis of covariance (MANCOVA), analysis of covariance (ANCOVA), and discriminate function analysis (DFA). We found the fish reared under hatchery conditions exhibit smaller brain size related to body weight, when compared to the wild ones. A significant (p<0.5) difference was observed in the length of CB and OT concerning the standard body length while no significant difference was found in TC of the fish from both the origins. The results of the current study highlight a logical assumption that neural deficiency affects the behaviour of fish, that's why the captive-reared fish show maladaptive response and face fitness decline when released to the natural environment for wild stock enhancement. The current study concluded that hatchery-reared fish exhibit variations in gross brain morphology as compared to their wild counterpart.

Observations during the COVID-19 pandemic in chronic heart failure patients with complex devices in a tertiary care cardiac centre using the HeartLogic software

Funding Acknowledgements

Type of funding sources: None.

Introduction

Decompensation of heart failure leading (HF) to hospitalisation is the single most important drain on healthcare resources when managing patients with left ventricular systolic dysfunction. Cardiac resynchronisation therapy with/without defibrillators (CRT-P/D) decreases hospitalisation due to HF and improves survival while implantable cardiac defibrillators (ICD"s) have a favourable effect on the former. Proprietary software algorithms embedded in these complex devices give an early warning to clinicians when decompensation of HF is imminent allowing preventative action to be undertaken.

HeartLogic (HL) is one such new algorithm in Boston Scientific CRT-D/ICD devices using multiple sensors to track 5 physiological parameters, combining them into one composite Index, with an Alert being triggered if the Index is >16. The COVID-19 pandemic, due to multiple reasons, resulted in a significant decrease in availability of routine HF services in the United Kingdom, especially during the initial lockdown period from 23rd March to 1st July 2020.

Aim

To assess the impact of the COVID-19 pandemic, using HL, in patients with HF and complex devices. 

Materials and Methods

Retrospective analysis of patients in a tertiary care cardiac centre in whom the HL software had been activated in March/April 2019 (n = 49) and comparison of those with (Group A n = 21) and without (Group B n = 28) an Alert (HLA) during the COVID-19 pandemic. 

Results (Table): Whole cohort n = 49. Age:  72 ± 12 years, Median: 75, Range: 36-95. 36/49 (73.5%) males. Type of device implanted: Resonate X4 CRT-D: 28/49 (57.1%); Momentum CRT-D: 8/49 (16.3%); Resonate ICD: 13/49 (26.5%). Ischaemic aetiology of HF: 35/49 (71.4%), Total duration of HL monitoring: 632 ± 7 days (median: 632; range: 626-672).  There was no difference in the age, gender, and type of device implanted between Group A and Group B. Over nearly ∼1 year of monitoring in each of the groups, Group A had more unstable HF with 10/21 (47.6%) having their first HLA during the pandemic. Multiple HLA"s, longer period in HLA and those with ischaemic aetiology of HF were higher in Group A. 17/40 (42.5%) HLA"s in Group A were within the first lockdown period (March - July). 24/28 (85.7%) patients in Group B had no HLA"s either before or during the pandemic. There was no difference in the HLA score between Groups A and B.

Conclusion

In this limited group of patients with a medium term follow-up, using the HeartLogic software, patients with ischaemic aetiology of HF and those with more HLA"s prior to the pandemic did worse than those who no HLA"s. First HLA"s, multiple alerts and longer duration of alerts in this group of patients suggests a lack of access to adequate HF services during the pandemic. It has implications with regard to how HF services are configured in future whenever resources are constrained.

Effect of different protein based feed on the growth of mahseer

For the proper growth of fish, it is necessary to feed the fish with a proper and balanced diet. A study was conducted to find out the effect of different protein-based diets on fingerlings of Tor putitora (mahseer). A feed with dietary protein levels of 35%, 40%, 45%, and 50% were prepared. The effect of different protein-based feed on weight gain, standard growth rate (SGR), food conversion ratio (FCR), percent weight gain, food conversion efficiency (FCE), and protein efficiency ratio (PER) was studied. An increase was observed in the growth rate with an increase in protein concentration up to 45%. The fingerlings fed a 45% protein diet shown the highest growth, followed by 50%, 40%, and 35%. The SGR value was greatest for 45% protein diet (8.56) followed by 50% and 40%, while the least values were observed for 35% protein feed (1.57). The same trend was observed for FCE. The highest PER values was observed in fishes fed 45% protein-based feed (0.65) followed by 50% (0.56), 40% (0.38) and35% (0.17). The food conversion ratio was lowest for 45% protein diet (3.41), while the greatest for 35% protein feed (16.85). It was concluded that a 45% protein-based diet was the best feed formulation for higher production of Tor putitora. However, research on the same percentage of protein diet is recommended for yearlings.

Effect of uniconazole and nitrogen level on lodging resistance and yield potential of maize under medium and high plant density

Lodging in maize results in grain yield reduction. This experiment investigated the effects of different application rates of the growth retardant, uniconazole (UCZ), and nitrogen (N) on medium and high maize population densities on lodging resistance and yield. UCZ was applied to maize seeds at concentrations of 0 (U₀ ) and 25 (U₂₅ ) mg kg^-1 , and three different N application rates, 0 (N₀ ), 150 (N₁₅₀ ) and 225 (N₂₂₅ ) kg ha^-1 , at plant densities of 75,000 (D₁ ) and 105,000 plants ha^-1 (D₂ ). UCZ application, different N rates and plant population density affected the lodging resistance and yield attributes of maize. The diameter, plumpness, cortex penetration and bending strengths of the internodes were enhanced with UCZ and N application at medium and high plant density, where maximum values were obtained with U₂₅ N₁₅₀ D₁ . Internode length increased in the high-density population and higher N rate, whereas UCZ reduced internode length, where maximum internode length was obtained with U₀ N₂₂₅ D₂ . Plant height, centre of gravity height, ear and height above ear-bearing node were higher with the high N rate, while UCZ reduced it significantly. UCZ, N rate and plant density enhanced lignin accumulation in the third internode and ear-bearing internode, where maximum values were obtained with U₂₅ N₁₅₀ D₁ . Yield and yield attributes were also improved by UCZ, N rate and population density. Treatment with U₂₅ N₁₅₀ D₂ significantly improved grain yield of maize compared with the other treatments.

Elliptic Flow of Electrons from Beauty-Hadron Decays in Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

The elliptic flow of electrons from beauty hadron decays at midrapidity (|y|<0.8) is measured in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV with the ALICE detector at the LHC. The azimuthal distribution of the particles produced in the collisions can be parametrized with a Fourier expansion, in which the second harmonic coefficient represents the elliptic flow, v_{2}. The v_{2} coefficient of electrons from beauty hadron decays is measured for the first time in the transverse momentum (p_{T}) range 1.3-6  GeV/c in the centrality class 30%-50%. The measurement of electrons from beauty-hadron decays exploits their larger mean proper decay length cτ≈500  μm compared to that of charm hadrons and most of the other background sources. The v_{2} of electrons from beauty hadron decays at midrapidity is found to be positive with a significance of 3.75  σ. The results provide insights into the degree of thermalization of beauty quarks in the medium. A model assuming full thermalization of beauty quarks is strongly disfavored by the measurement at high p_{T}, but is in agreement with the results at low p_{T}. Transport models including substantial interactions of beauty quarks with an expanding strongly interacting medium describe the measurement within uncertainties.

In-vitro and in-vivo evaluation of the antibacterial potential of Typha elephantina

The present study was aimed to evaluate the in-vitro and in-vivo antibacterial effects of the Typha elephantina aqueous extract (TE.AQ), ethanolic extract (TE.ET) and T. elephantina methanolic extract (TE.ME) against eight selected clinical pathogens. The test samples were tested for in-vitro analysis (by disc diffusion method) at different concentrations of 5, 15, 25, 50 and 100 mg/dL against both gram positive and gram-negative strains. The highest potential was observed in TE.ME at a concentration of 100 mg/dL against Pseudomonas aeruginosa exhibiting 19.67 ± 0.577 mm zone of inhibition (ZOI). The same fraction also showed good activity against Staphylococus aureus with ZOI of 17.50 ± 0.70 mm. The TE.ET was found most active against P. aeruginosa and Streptococcus pyogenes having ZOI of 18.53 ± 0.503 and 16.2 ± 1.55 mm respectively at a concentration of 100 mg/dL. The most sensitive bacteria P. aeruginosa was selected for in-vivo study (using poultry chicks) for induction of infection in chicks. The effects of TE.AQ, TE.ET and TE.ME were determined at concentrations of 300 mg/kg body weight based on hematological parameters, liver enzymes and gross pathological findings of lungs and livers. The findings of the in-vivo study in chick's model showed that treatment of experimental animals with TE.ME significantly restored the hematological parameters, liver enzymes and architecture of lungs and livers. Based on scientific evidence, the current study suggests that TE.ME may serve as a best and new natural antibacterial agent and can be used against infections caused by P. aeruginosa.

Swept Langmuir probe investigation of a time varying DC discharge

The paper reports on the development and application of a swept Langmuir probe to characterize plasma between two disc-like electrodes. A battery was added to a probe circuit to offset against the cathode fall voltage, and to make the sweep voltage effective at the probe tip. This arrangement allowed the collection of the electron and ion parts of the probe current and the subsequent construction of time-resolved current–voltage IP(V) characteristics with a time resolution of about one millisecond. The probe collected electron current in the lower voltage region of the discharge waveform where it surmounted the cathode fall voltage, whereas the ion current was collected continuously due to an accelerating field for the ions. The results highlighted how the cathode fall voltage limits the collection of the electron and ion parts of the probe current and how to handle the problem with a series battery in the probe circuit. In addition to the swept single-probe, a triple-probe was used simultaneously to compare and validate the results.

Impact of COVID-19 on the cerebrovascular system and the prevention of RBC lysis

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) uses Angiotensin- converting enzyme 2 (ACE2) receptors to infect host cells which may lead to coronavirus disease (COVID-19). Given the presence of ACE2 receptors in the brain and the critical role of the renin-angiotensin system (RAS) in brain functions, special attention to brain microcirculation and neuronal inflammation is warranted during COVID-19 treatment. Neurological complications reported among COVID-19 patients range from mild dizziness, headache, hypogeusia, hyposmia to severe like encephalopathy, stroke, Guillain-Barre Syndrome (GBS), CNS demyelination, infarcts, microhemorrhages and nerve root enhancement. The pathophysiology of these complications is likely via direct viral infection of the CNS and PNS tissue or through indirect effects including post- viral autoimmune response, neurological consequences of sepsis, hyperpyrexia, hypoxia and hypercoagulability among critically ill COVID-19 patients. Further, decreased deformability of red blood cells (RBC) may be contributing to inflammatory conditions and hypoxia in COVID-19 patients. Haptoglobin, hemopexin, heme oxygenase-1 and acetaminophen may be used to maintain the integrity of the RBC membrane.

A Multicenter Study of the Clinical Utility of Nontargeted Systematic Transperineal Prostate Biopsies in Patients Undergoing Pre-Biopsy Multiparametric Magnetic Resonance Imaging

PURPOSE

The added value of nontargeted systematic prostate biopsies when performed alongside magnetic resonance imaging targeted biopsies in men referred with a suspicion of prostate cancer is unclear. We aimed to determine the clinical utility of transperineal nontargeted systematic prostate biopsies, when performed alongside targeted systematic prostate biopsies, using pre-biopsy multiparametric magnetic resonance imaging.

MATERIALS AND METHODS

Consecutive patients referred with a suspicion of prostate cancer (April 2017 to October 2019) underwent pre-biopsy multiparametric magnetic resonance imaging. A transperineal biopsy was advised if multiparametric magnetic resonance imaging PI-RADS® (v.2.0) score was 4 or 5, and score 3 required a prostate specific antigen density 0.12 ng/ml or greater. Primary threshold for clinically significant prostate cancer was defined as any Gleason 3+4 or greater. Multivariable logistic regression analysis identified pre-biopsy predictors of clinically significant prostate cancer in nontargeted systematic prostate biopsies, regardless of targeted pathology (p <0.05, R, version 3.5.1).

RESULTS

A total of 1,719 men underwent a pre-biopsy multiparametric magnetic resonance imaging, with 679 (39.5%) proceeding to combined targeted systematic prostate biopsies and nontargeted systematic prostate biopsies. In these men clinically significant prostate cancer was detected in 333 (49%) and 139 (20.5%) with targeted systematic prostate biopsies and nontargeted systematic prostate biopsies, respectively. In those men with clinically significant prostate cancer in targeted systematic prostate biopsies, clinically significant prostate cancer was also present in nontargeted systematic prostate biopsies in 117 (17.2%); Gleason 3+3 was present in 50 (7.4%). In 287 men without any cancer in the targeted systematic prostate biopsies, 13 (1.9%) had clinically significant prostate cancer in nontargeted systematic prostate biopsies. In addition 18/679 (2.7%) had Gleason 3+3 disease and no Gleason greater than 4+3 was detected. Predictors associated with clinically significant prostate cancer in nontargeted systematic prostate biopsies were prostate specific antigen 5 ng/ml or greater (OR 2.05, 95% CI 1.13-3.73, p=0.02), PI-RADS score 5 (OR 2.26, 95% CI 1.51-3.38, p <0.001) and prostate volume less than 50 cc (OR 2.47, 95% CI 1.57-3.87, p <0.001).

CONCLUSIONS

Detection of clinically significant prostate cancer in exclusively nontargeted transperineal systematic biopsies in a pre-biopsy multiparametric magnetic resonance imaging pathway was low (1.9%).