A computational quest for identifying potential vaccine candidates against Moraxella lacunata: a multi-pronged approach

Moraxella lacunata is an emerging gram-negative bacterium that is responsible for multiple nosocomial infections. The bacterium is evolving resistance to several antibiotics, and currently, no effective licensed vaccines are available, which warrants the search for new therapeutics. A multi-epitope-based vaccine has been designed for M. lacunata. The complete proteome of M. lacunata contains 10,110 core proteins. Subcellular localization analysis revealed the presence of five proteins in the extracellular matrix, while 19 proteins were predicted to be located in the outer membrane, and 21 proteins were predicted to be located in the periplasmic region. Only two proteins, the type VI secretion system tube protein (Hcp) and the transporter substrate-binding domain-containing protein, were selected for epitope prediction as they fulfilled all the criteria for being potential vaccine candidates. Shortlisted epitopes from the selected proteins were fused together using "GPGPG" linkers to overcome the limitations of single-epitope vaccines. Next, the cholera toxin-B adjuvant was attached to the peptide epitope using an EAAAK linker. Docking analysis was performed to examine the interaction between the vaccine and immune cell receptors, revealing robust intermolecular interactions and a stable binding conformation. Molecular dynamics simulation findings revealed no drastic changes in the binding conformation of complexes during the simulation period. The net binding free energy of vaccine-receptor complexes was estimated using the molecular mechanics energies combined with the Poisson-Boltzmann and surface area continuum solvation (MM-PBSA) method. The reported values were -586.38 kcal/mol, -283.74 kcal/mol, and -296.88 kcal/mol for the TLR-4-vaccine complex, MHC-I-vaccine complex, and MHC-II-vaccine complex, respectively. Furthermore, the molecular mechanics energies combined with the generalized Born and surface area continuum solvation (MM-GBSA) analysis predicted binding free energies of -596.69 kcal/mol, -287.39 kcal/mol, and -298.28 kcal/mol for the TLR-4-vaccine complex, MHC-I-vaccine complex, and MHC-II-vaccine complex, respectively. The theoretical vaccine design proposed in the study could potentially serve as a powerful therapeutic against targeted pathogens, subject to validation through experimental studies.Communicated by Ramaswamy H. Sarma.

Berberine Nanoparticles with Enhanced in vitro Bioavailability: Characterization and Antimicrobial Activity [Retraction]

[This retracts the article DOI: 10.2147/DDDT.S156123.].

A chemoinformatic-biophysics based approach to identify novel anti-virulent compounds against Pseudomonas aeruginosa disulfide-bond protein A1

The conventional course of drug discovery is a lengthy, expensive and complex process and often experiences a high failure rate. This in-silico based study screened novel drug molecules against Pseudomonas aeruginosa disulfide-bond protein A1 (PaDsbA1; PDB ID of 4ZL7) using a variety of chemoinformatic and biophysics approaches. The structure-based virtual screening identified three antipseudomonal compounds (BDC_30129064, BDC_20699588 and BDC_25329008) that targeted PaDsbA1 enzyme with a binding energy score of -7.8 kcal/mol, -7.7 kcal/mol and -7.7 kcal/mol, respectively. The compounds revealed deep binding at the enzyme active pocket with close distance hydrogen bond interactions with Thr46, Pro55, Val58, Arg62, His88, and Asp180. The co-crystalized hexaethylene glycol revealed a binding energy of -6.02 kcal/mol. The docked compounds were further subjected to molecular dynamics simulation analysis in order to check the dynamic movements of docked complexes. The complexes reported no drastic changes during simulation time. In the simulation, stable compounds binding and docked conformation were accomplished. The docking and simulation results were validated using free binding energies calculation through molecular mechanics with generalized born surface area solvation and molecular mechanics Poisson Boltzmann surface area (MMGBSA/MMPBSA) approaches. The net binding energy estimated by MMGBSA for BDC_30129064, BDC_20699588 and BDC_25329008 was -75.07 kcal/mol, -77.87 kcal/mol and -59.1 kcal/mol, respectively while that of MMPBSA for the compounds was -72.47 kcal/mol, -78.99 kcal/mol and -60.991 kcal/mol, respectively. The physiochemical properties of the selected compounds indicated them to be physiochemically stable with good absorption, distribution, metabolism and elimination properties. From the above observations and predictions, the compounds can be recommended for further experimental validation in order to decipher their anti-virulence capacity in blocking disulfide bond formation in P. aeruginosa.Communicated by Ramaswamy H. Sarma.

The management of dialysis access thrombosis during the COVID-19 pandemic

BACKGROUND

Maintaining patent access is essential for haemodialysis dependent end stage renal failure patients. The COVID-19 pandemic has significantly affected surgical and interventional radiology services worldwide. We aimed to review the impact COVID-19 has caused to the management of acute dialysis access thrombosis.

METHODS

We conducted a single centre retrospective review of outcomes of patients with arteriovenous fistula and arteriovenous graft thrombosis between March and May 2020, which coincided with the first peak of the COVID-19 pandemic in London, and a similar period in the previous year, March-May 2019. Outcomes in both cohorts of patients were compared, including attempts at salvage, salvage success, 1-month patency rates after salvage and subsequent surgery on the same access. We also analysed the use of tunnelled haemodialysis lines (THL), either due to failed salvage attempts or when salvage was not attempted.

RESULTS

There was a similar incidence of access thrombosis in both periods (26 cases in 2019, 38 in 2020). There were 601 patients dialysing via an arteriovenous fistula or graft in 2019, and 568 patients in 2020. Access salvage, when attempted, had similar success rates and 1-month patency (salvage success 74% vs 80%, p = 0.39; 1-month patency 55% vs 62%, p = 0.69). The proportion of patients where access salvage was not attempted and a THL inserted was significantly higher in 2020 compared to 2019 (32% vs 4%, p = 0.007). There were more patients who subsequently had surgery to salvage or revise the same access in 2019 compared to 2020 (62% vs 13%, p < 0.001).

CONCLUSIONS

During the peak of the COVID-19 pandemic, there were fewer attempts at access salvage. This was a conscious decision due to increased pressure on the healthcare system, access to emergency interventional radiology or operative theatres and the perceived risk/benefit ratio of access salvage. The long-term effects of this change in practice remain unknown.

Experimental Investigation of Engine Valve Train Friction Considering Effects of Operating Conditions and WPC Surface Treatment

Reduction in friction ensures fuel economy, control on emissions and durability of components in internal combustion engines. A modern gasoline internal combustion engine was instrumented to determine the friction values at the cam-roller interface considering the effects of surface treatment and engine operating state. A series of tests under different operating speeds and lubricant inlet temperatures were undertaken using both an original surface roller and a Wonder Process Craft (WPC) surface-treated engine roller. The results clearly revealed a substantial reduction in friction magnitude for the WPC surface-treated engine roller in comparison to the original roller while operating under similar conditions, indicating their strong potential for employment in engines. An increase in friction with the rise in temperature was also observed for both types of rollers, whereas increased lubricant entraining velocity due to higher operating speed had the opposite impact. A considerable reduction in frictional drive torque ranging from 8% to 28% was observed by employing the WPC-treated roller in comparison to original/untreated roller at various operating conditions, which signifies the strong potential for employment of WPC surface treatment in the roller/follower valve train engines.

Machine Learning Model for Assessment of Risk Factors and Postoperative Day for Superficial vs Deep/Organ-Space Surgical Site Infections

Background. Deep and organ space surgical site infections (SSI) require more intensive treatment, may result in more severe clinical disease and may have different risk factors when compared to superficial SSIs. Machine learning (ML) algorithms provide the opportunity to analyze multiple factors to predict of the type and time of development of SSI. Therefore, we developed a ML model to predict type and postoperative week of SSI. Methodology. A case-control study was conducted among patients who developed a SSI after undergoing general surgery procedures at a tertiary care hospital between 2019 to 2020. Patients were followed for 30 days. Six ML algorithms were trained as predictors of type of infection (superficial vs deep/organ space) and time of infection, and tested using area under the receiver operating characteristic curve (AUC-ROC). Results. Data for 113 patients with SSIs was available. Of these 62 (54.8%) had superficial and 51 had (45.2%) deep/organ space infections. Compared with other ML algorithms, the XG boost univariate model had highest AUC-ROC (.84) for prediction of type of SSI and Stochastic gradient boosting univariate, logistic regression univariate, XG boost univariate, and random forest classification univariate model had the highest AUC-ROC (.74) for prediction of week of infection. Conclusions. ML models offer reasonable accuracy in prediction of superficial vs deep SSI and time of developing infection. Follow-up duration and allocation of treatment strategies can be informed by ML predictions.

Management of infected arteriovenous grafts for haemodialysis: Outcomes and strategies using a novel objective scoring system

BACKGROUND

In haemodialysis patients with exhausted autogenous options, prosthetic arteriovenous grafts (AVGs) are frequently utilised as tertiary vascular access. However, the prosthetic nature of AVGs precipitates an increased risk of infection which may translate to excess morbidity and life-threatening complications. The current evidence remains divided on the optimal treatment strategy for arteriovenous graft infections (AVGi) with arguments for conservative management by antibiotics, salvaging with graft revision or total/subtotal excision. To address this gap, we assessed the outcomes of AVGi patients treated in our institution, developing an AVGi severity classification model and a proposed treatment algorithm to guide AVGi management.

METHODS

We conducted a single centre retrospective review of outcomes of patients with AVGi managed either by sole antibiotics therapy, graft revision or surgical excision between June 2016 and May 2021. Outcomes of AVGi patients across differing treatment groups were compared, including 1-year mortality, 6-month and 1-year functional vascular access. We also analysed the outcomes of tunnelled haemodialysis lines (THL), which were used as a temporary vascular access in several AVGi patients in our study.

RESULTS

A total of 34 AVGi patients were managed within that time frame and included in the study (5 conservatively management by antibiotics, 5 graft revisions and 24 surgical excision) with a mean age of 60.4 ± 14.4 years (67.6% males). Overall 1-year mortality was 14.7%. A 6-month functional vascular access status across the three groups stood at 60%, 60% and 10% while 1-year functional vascular access status was 60%, 75% and 42% respectively.

CONCLUSIONS

When clinically appropriate, conservative management by antibiotics or salvage/graft revision can present as prudent AVGi treatment options. The adoption of our proposed severity classification system and treatment algorithm provides a more thorough objective assessment of the infection and helps guide the clinical decision-making process.

Rapid Testing System for Rice Quality Control through Comprehensive Feature and Kernel-Type Detection

The assessment of food quality is of significant importance as it allows control over important features, such as ensuring adherence to food standards, longer shelf life, and consistency and quality of taste. Rice is the predominant dietary source of half the world’s population, and Pakistan contributes around 80% of the rice trade worldwide and is among the top three of the largest exporters. Hitherto, the rice industry has depended on antiquated methods of rice quality assessment through manual inspection, which is time consuming and prone to errors. In this study, an efficient desktop-application-based rice quality evaluation system, ‘National Grain Tech’, based on computer vision and machine learning, is presented. The analysis is based on seven main features, including grain length, width, weight, yellowness, broken, chalky, and/or damaged kernels for six different types of rice: IRRI-6, PK386, 1121 white and Selah, Super kernel basmati brown, and white rice. The system was tested in rice factories for 3 months and demonstrated 99% accuracy in determining the size, weight, color, and chalkiness of rice kernels. An accuracy of 98.8% was achieved for the classification of damaged and undamaged kernels, 98% for determining broken kernels, and 100% for paddy kernels. The results are significant because the developed system improves the local rice quality testing capacity through a faster, more accurate, and less expensive mechanism in comparison to previous research studies, which only evaluated four features of the singular rice type, rather than the seven features achieved in this study for six rice types.

Haematological profile abnormalities; and its relationship with severity and outcome of COVID-19 infection

Background

Corona virus disease (Covid-19) caused by corona virus (SARS Cov-2) has affected millions of people around the world. Many diagnostic modalities have been tested but the blood complete picture remains the initial and most easily accessible investigation in Covid-19.

Objectives

The objective of this study was to find out the haematological abnormalities in relation to Covid-19 severity and outcome.

Methods

This cross-sectional study was carried out from April 2020 to July 2020. One--hundred and fifty polymerase chain reaction (PCR) confirmed Covid-19 patients were inducted by random sampling. Haematological profile at admission was recorded. Data thus obtained was analyzed with respect to Covid-19 severity and outcome. The data was entered and analyzed using Statistical Package for Social Sciences (SPSS) version 19.

Results

Out of a total of 150 patients included in the study, 77(51.3%) patients had mild disease at the time of admission, 42 (28%) had moderate disease while 31 (20.7%) had critical disease at the time of admission. Medians (interquartile range) of total leucocyte count (TLC), neutrophils, lymphocytes, neutrophils to lymphocytes ratio (NLR), platelets to lymphocytes ratio (PLR), neutrophils to monocyte ratio (NMR), monocyte to lymphocyte ratio (MLR) were 8.11 (IQR=4.88), 5.95 (IQR=4.58), 1.66 (IQR=1.10), 3.48 (IQR=4.20), 146.24 (IQR=130.75), 18.87 (IQR=14.07), 0.16 (IQR=0.13). Median NLR was higher in patients with critical illness 11.23 (IQR=10.70) as compared to those with stable 2.51 (IQR=1.77) and moderate 3.22 (IQR=3.60) disease (p< 0.000). Similarly TLC (p< 0.000), neutrophils (p< 0.000), lymphocytes (p< 0.000), NLR (p< 0.000), PLR (p< 0.000, p=0.001), MLR (p< 0.000), NMR (p< 0.000) had significant relationship with the severity and outcome of Covid-19 infection.

Conclusion

Many haematological parameters are significantly different and can be used to predict the severity and outcome of Covid-19 infection.

O029 Long term outcomes of renal transplants in kidneys with multiple arteries

Introduction

Variations in kidney arterial anatomy may affect decisions regarding implantation, and in some cases require multiple anastomoses or reconstruction. We aimed to assess the effect of multiple arteries on transplant outcomes.

Methods

We performed a registry analysis of UK kidney transplants from 2000–2018. Univariate and

Multi-variate analyses were performed to assess the effect of multiple arteries on graft outcomes including graft function and the incidence of DGF and vascular thrombosis.

Results

13240 living donor (LD) and 28095 deceased donor (DD) transplants were analysed. Warm ischaemic times in single artery kidneys was lower than kidneys with multiple arteries (LD 42 vs 45mins, p=0.025, DD 40 vs 43mins, p&lt;0.001). Donor characteristics were similar between both groups. When adjusted for age, sex, diabetes, cold and warm ischaemic time, there was no difference in mean creatinine at 3, 12 or 60 months in LD and DD with single or multiple arteries. There was an increased incidence in vascular thrombosis seen in LDs with multiple arteries (2.2% vs 4.5%, p=0.008), but not in DDs (3.7% vs 4.0%, p=0.584). There was no difference in DGF or PNF. In LDs, multiple arteries had no effect on transplant survival time (p=0.473), but DDs with multiple arteries had poorer survival (5493 vs 5649 days, p=0.007).

Conclusion

While multiple arteries may pose technical challenges and are associated with longer warm ischaemic times, the clinical implications of this are minimal. The increased risk of graft thrombosis in LDs is clinically relevant but long-term graft survival and graft outcomes remain excellent.

Take-home message

Kidneys with multiple arteries can make transplantation more technically challenging, but this has minimal effects on long term graft outcomes.

Pan-Genome Analysis of Oral Bacterial Pathogens to Predict a Potential Novel Multi-Epitopes Vaccine Candidate

Porphyromonas gingivalis is a Gram-negative anaerobic bacterium, mainly present in the oral cavity and causes periodontal infections. Currently, no licensed vaccine is available against P. gingivalis and other oral bacterial pathogens. To develop a vaccine against P. gingivalis, herein, we applied a bacterial pan-genome analysis (BPGA) on the bacterial genomes that retrieved a total number of 4908 core proteins, which were further utilized for the identification of good vaccine candidates. After several vaccine candidacy analyses, three proteins, namely lytic transglycosylase domain-containing protein, FKBP-type peptidyl-propyl cis-trans isomerase and superoxide dismutase, were shortlisted for epitopes prediction. In the epitopes prediction phase, different types of B and T-cell epitopes were predicted and only those with an antigenic, immunogenic, non-allergenic, and non-toxic profile were selected. Moreover, all the predicted epitopes were joined with each other to make a multi-epitopes vaccine construct, which was linked further to the cholera toxin B-subunit to enhance the antigenicity of the vaccine. For downward analysis, a three dimensional structure of the designed vaccine was modeled. The modeled structure was checked for binding potency with major histocompatibility complex I (MHC-I), major histocompatibility complex II (MHC-II), and Toll-like receptor 4 (TLR-4) immune cell receptors which revealed that the designed vaccine performed proper binding with respect to immune cell receptors. Additionally, the binding efficacy of the vaccine was validated through a molecular dynamic simulation that interpreted strong intermolecular vaccine-receptor binding and confirmed the exposed situation of vaccine epitopes to the host immune system. In conclusion, the study suggested that the model vaccine construct has the potency to generate protective host immune responses and that it might be a good vaccine candidate for experimental in vivo and in vitro studies.

Prevalence and Biochemical Associations of Fever in Adults With Reverse Transcription Polymerase Chain Reaction Proven Coronavirus Disease Presenting at Tertiary Care Hospitals in Rawalpindi

Background

Clinically most apparent symptoms of COVID-19 include fever and cough, which in some patients show a worsening trend but are completely non-apparent in patients who present with an asymptomatic course of the disease. The aim of this study was to identify clinical and biochemical differences among polymerase chain reaction (PCR) positive patients who are either febrile or afebrile.

Methods

This study was conducted in Rawalpindi Medical University and Allied Hospitals between September and December 2020. All patients who tested positive for reverse transcription polymerase chain reaction (RT-PCR) COVID-19 were included in the study. After evaluation of 146 patients, 100 were selected, and with a response rate of 97%, a total of 97 patients were included in the final analysis. Depending on the presence of fever, the participants were divided into two groups. Both groups were then compared for baselines vitals and laboratory investigations. Data was entered and analyzed in SPSS v23.0 (IBM Inc., Armonk, New York).

Results

Among the 97 patients, 66 (68%) of the participants were male, and 31 (32%) were females. The mean age of the study participants was 45.23±18.08 years. Fever was present in 39 (40.2%) of the participants. When compared with patients with no fever, the patients with fever had greater severity of disease (p<0.001), higher heart rate (p<0.001), decreased oxygen saturation (p<0.001). Among the laboratory investigations, the fever group had a greater tendency of having deranged alanine aminotransferase (ALT) (70.82±29.23 vs. 32.83±16.22, p=0.010), Lymphocytes (1.56±0.54 vs. 2.12±0.94, p=0.003) and serum total bilirubin (1.06±0.36 vs. 0.55±0.21, p=0.009). Based on multiple regression analysis, the presence of fever is a predictor of derangement in ALT (OR=1.034, CI=1.001-1.068 p=0.025) and total bilirubin (OR=4.38, CI=2.14-6.78, p=0.021).

Conclusion

Fever may not be present among all patients presenting with COVID-19 infection, but those who have a fever have a greater risk of having deranged liver function tests. Hence, it is important to monitor liver function tests (LFTs) in COVID-19 patients presenting with fever. 

Detection of Anti-Echinococcus granulosus Antibodies in Humans: An Update from Pakistan

Human cystic echinococcosis (CE) is a zoonotic disease caused by the larval stage of Echinococcus granulosus sensu lato that causes economic losses by affecting livestock and also poses a public health threat worldwide. The present study is the first retrospective report on the seroprevalence of anti-E. granulosus antibodies in humans in Pakistan. The study used data from 93 blood analysis reports of patients suspected of having CE from different medical centers in Lahore, Pakistan. Out of 93 sera samples, 20 (21.5%) were seropositive, and higher seropositivity (17.2%) was recorded with the indirect hemagglutination test (IHA) than with enzyme-linked immunosorbent assay (ELISA). The findings indicated that age, gender, and year had no significant relationship with the seropositivity of CE. The current study provides directions towards the management of the disease in the near future in Pakistan.

Presenting Complaints in Acute Dengue Infection and Differences in Presenting Complaints Between Primary and Secondary Dengue Infections

Aim and objectives

To describe the presenting complaints in acute dengue infection, and identify any differences in presenting complaints between primary and secondary dengue infection patients.

Material and methods

This cross-sectional observational study was conducted at the Department of Infectious Diseases and Medicine, Holy Family Hospital, Rawalpindi, from July 2019 to December 2019 during the Dengue Rawalpindi Epidemic 2019. Presenting complaints of patients who fulfilled the inclusion criteria of the study were recorded on a proforma on their admissions and their informed consent was taken. Of these patients, 70 primary and 70 secondary dengue infection patients were randomly selected for comparison of presenting complaints. The two groups were compared using the chi-square test and a P-value of <0.05 was considered significant.

Results

Intermittent fever (88.6%), headache (85%), myalgia (87.9%), arthralgia/bone pain (75%), and retro-orbital pain (47.9%) were common in most dengue patients. Hemorrhagic manifestations, such as rash (15%), epistaxis (11.4%), gum bleeding (15%), melena (7.9%), hematemesis (6.4%), hemoptysis (5.7%), and hematuria (6.4%), were less common.

Abdominal pain was significantly more common in secondary dengue infections (50% in secondary dengue infections compared to 32.9% in primary dengue infections).

Conclusions

Fever, headache, myalgia, arthralgia/bone pains, retro-orbital pain as well as rash, epistaxis, gum bleeding, melena, hematemesis, hemoptysis, hematuria, and decreased urine output despite fluid intake are presenting complaints of dengue infection.

Patients with abdominal pain in addition to the above presenting complaints are more likely to be cases of the more serious secondary dengue infection. 

Correlation of biochemical profile at admission with severity and outcome of COVID-19

Background

COVID-19 was detected in China in December 2019. The rapid dissemination and novelty of the disease resulted in an epidemic. This study aimed to identify biochemical parameters at admission that can be used to categorize severity and outcome of COVID -19 infection.

Materials and Methods

This cross-sectional study was conducted at Allied Hospitals of RMU from April 2020 to July 2020. It included 128 randomly selected confirmed COVID-19 patients. At admission, biochemical profile (total bilirubin, alanine aminotransferases {ALT}, aspartate aminotransferases {AST}, urea, creatinine, uric acid, sodium, potassium, and chloride were correlated with severity and outcome of COVID-19 by employing t-tests and ANOVA where required. Cut-off values to predict disease severity and outcome were calculated using ROC curve.

Results

The study comprised 46.1% non-severe, 29.7% severe, and 24.2% critical COVID-19 patients. 84.4% patients improved and 15.6% expired. Urea was increased in critical disease patients (p < 0.000). Higher ALT (p 0.030) and AST (p 0.004) levels were noted in severe and critical disease. Sodium (p 0.001) and chloride (p 0.026) were decreased in critical disease. Patients who expired had increased urea (p 0.000), ALT (p 0.040) and AST (p 0.002). At admission, urea >42.7 mg (sensitivity of 64.7%, specificity of 87.5%), AST >43.5 IU/L (64% sensitivity, 60% specificity), and sodium <136.9 mmol/L (sensitivity of 70.6%, specificity of 71.2%) predicted critical COVID-19 infection.

Conclusion

At admission, increased urea, AST, and ALT along with decreased sodium can help in identifying COVID-19 patients with severe illness and poor outcome.

Synonymous and non-synonymous polymorphisms in toll-like receptor 2 (TLR2) gene among complicated measles cases at a tertiary care hospital, Peshawar, Pakistan

Objectives:

To detect single nucleotide polymorphism in toll-like receptor 2 (TLR2) gene in complicated cases of measles, in order to understand the genetic basis of complex human immune responses against measles complications.

Methods:

A total of 100 children consisted of 50 measles complicated cases while rest were gender matched disease-free individuals who served as controls for this study. Patient demographic data and clinical information were recorded on a separate pre-designed model form. All exonic regions of TLR2 gene of the patients and control samples were amplified through polymerase chain reaction. Various in-silico mutation verification tools like protein variation effect analyzer, MUPRO, sorting intolerant from tolerant, functional analysis through hidden Markov models, and polymorphism phenotyping v2 to study the effect of novel non-synonymous polymorphism on structure and function of TLR2 protein.

Results:

Synonymous and novel non-synonymous polymorphisms were identified in measles complicated cases. Among these, rs1816702 was marked to 5 untranslated region section of TLR2 gene, while rs3804099 and rs3804100 were identified in the coding region. Novel non-synonymous polymorphisms were shown in the coding region of TLR2 gene. No significant association was established between the observed genetic polymorphisms and measles complications. However, rs3804100 increased the risk of lower respiratory tract infection.

Conclusion:

The overall impact of novel non-synonymous polymorphism of TLR2 protein structure and functions was neutral and tolerated.

Trimester-specific reference ranges for thyroid hormones of pregnant females at tertiary care hospitals in Lahore, Pakistan

BACKGROUND

The significance of investigation for diagnosing and managing thyroid dysfunction in pregnant females has been extensively documented in the medical literature. This study aimed to determine trimester-specific reference ranges for thyroid-stimulating hormones (TSH), free T3 (FT3), and free T4 (FT4) in apparently healthy pregnant women attending tertiary care hospitals in Lahore.

METHODS

This cross-sectional study was conducted at two tertiary care Hospitals in Lahore, Pakistan. In this multi-centric study, 500 pregnant females were initially enrolled from September 2019 to December 2019 who fulfilled the inclusion criteria. For measurement of serum FT3, FT4, thyroid stimulating hormone (TSH), anti-thyroid peroxidase (anti-TPO), and thyroglobulin antibodies, 5 ml of the blood sample was drawn, under aseptic conditions, from each subject using Maglumi 800 chemiluminescence immunoassay (CLIA) system.

RESULTS

Out of 500 subjects, 23 subjects with positive anti-TPO, 19 subjects with anti-TG antibodies, and 12 subjects due to less volume of serum yielded from whole blood (serum less than 3 ml) were excluded from the analysis. Ten samples were hemolyzed and not included in the analysis. A total of 436 samples were examined for analysis. Of the remaining 436 subjects, 133 (30.5%) were from 1st trimester, 153 (35.1%) from 2nd trimester, and 150 (34.4%) from 3rd trimester. As the data were non-normal, the 2.5th, 50th, and 97.5th percentiles were calculated to express each group's results. Trimester specific range of TSH 0.168-4.294, 0.258-4.584 and 0.341-4.625 mIU/mL, FT31.857-4.408, 1.958-4.621 and 2.025-4.821 pmol/L and FT4 8.815-18.006, 8.306-17.341 and 7.402-17.292 pmol/L.

CONCLUSION

In this study, we established a trimester-specific reference range for our local population's thyroid function test. The results of this study have complemented the results of previous studies.

Cytogenetic abnormalities in patients with hematological malignancies in Lahore city, Pakistan

Hematological and hematopoietic cells malignancies of the genes and hematopoietic cells are associated with the genetic mutation, often at the chromosomal level. The standard cytogenetic study is widely accepted as one of the main diagnostics and prognostic determinants in patients. Therefore, the current descriptive and cross-sectional study sought to determine the cytogenetic analysis of frequent hematological malignancies in Pakistan. A total of 202 peripheral bone marrow or blood samples from patients with benign and malignant hematological malignancy were taken using a conventional G-banding technique. Among enrolled patients, the mean age was 21.5 years ± 23.4, and gender-wise distribution showed a marked predominance of the male 147 (73%) population compared to the female 55 (27%). Patients in the age group (2-10 years) had the highest frequency, 48 (24%), of hematological neoplasms, followed by age (11-20 years) with 40 (20%). Normal karyotypes (46, XX/46, XY) was found in 51% (n=103) patients. Furthermore, the frequency of complex karyotype was 30 (15%), while normal was seen in 171 (85%) patients. Pre-B Acute Lymphoblastic Leukemia (Pre-B ALL) was the most prevalent malignancy of 66 (33%), followed by Chronic Myelogenous Leukemia (CML) of 41 (20%) and Acute Lymphocytic Leukemia of 29 (14%). Translocation was the most prevalent 50 (25%), followed by hypotriploidy 14 (7%) and monosomy 8 (4%) on chromosome aberration analysis. In addition, t(9:22) translocation was found to be 20 (10%) in CML, with the majority in the age group (31-40 years). This study recommends that karyotyping should be tested frequently in hematological conditions because it may provide insight into the relative chromosomal changes associated with particular malignancies.

Towards A Novel Multi-Epitopes Chimeric Vaccine for Simulating Strong Immune Responses and Protection against Morganella morganii

Morganella morganii is one of the main etiological agents of hospital-acquired infections and no licensed vaccine is available against the pathogen. Herein, we designed a multi-epitope-based vaccine against M. morganii. Predicted proteins from fully sequenced genomes of the pathogen were subjected to a core sequences analysis, followed by the prioritization of non-redundant, host non-homologous and extracellular, outer membrane and periplasmic membrane virulent proteins as vaccine targets. Five proteins (TonB-dependent siderophore receptor, serralysin family metalloprotease, type 1 fimbrial protein, flagellar hook protein (FlgE), and pilus periplasmic chaperone) were shortlisted for the epitope prediction. The predicted epitopes were checked for antigenicity, toxicity, solubility, and binding affinity with the DRB*0101 allele. The selected epitopes were linked with each other through GPGPG linkers and were joined with the cholera toxin B subunit (CTBS) to boost immune responses. The tertiary structure of the vaccine was modeled and blindly docked with MHC-I, MHC-II, and Toll-like receptors 4 (TLR4). Molecular dynamic simulations of 250 nanoseconds affirmed that the designed vaccine showed stable conformation with the receptors. Further, intermolecular binding free energies demonstrated the domination of both the van der Waals and electrostatic energies. Overall, the results of the current study might help experimentalists to develop a novel vaccine against M. morganii.

Pharmacological evaluation of the gabapentin salicylaldehyde derivative, gabapentsal, against tonic and phasic pain models, inflammation, and pyrexia

Gabapentinoids are effective drugs in most animal models of pain and inflammation with variable effects in humans. The current study evaluated the pharmacological activity of gabapentin (GBP) and its salicylaldehyde derivative (gabapentsal; [2-(1-(((2-hydroxybenzylidene) amino) methyl) cyclohexyl) acetic acid]; GPS) in well-established mouse models of nociceptive pain, inflammatory edema, and pyrexia at doses of 25-100 mg/kg. GPS allayed tonic visceral pain as reflected by acetic acid-induced nociception and it also diminished thermally induced nociception as a mimic of phasic thermal pain. Antagonism of GPS-induced antinociceptive activities by naloxone (NLX, 1.0 mg/kg, subcutaneously, s.c), beta-funaltrexamine (β-FNT, 5.0 mg/kg, s.c), naltrindole (NT, 1.0 mg/kg, s.c), and nor-binaltorphimine (NOR-BNI, 5.0 mg/kg, s.c), and pentylenetetrazole (PTZ-15 mg/kg, intraperitoneally, i.p) implicated an involvement of both opioidergic and GABAergic mechanisms. Tail immersion test was conducted in order to delineate the mechanistic insights of antinociceptive response. Inflammatory edema induced by carrageenan, histamine, or serotonin was also effectively reversed by GPS in a fashion analogous to aspirin (150 mg/kg, i.p), chlorpheniramine (1.0 mg/kg, i.p), and mianserin (1.0 mg/kg, i.p), respectively. Additionally, yeast-induced pyrexia was decreased by GPS in a comparable manner to acetaminophen (50 mg/kg, i.p). These observations suggest that GPS possesses ameliorative properties in tonic, phasic, and tail immersion tests of nociception via opioidergic and GABAergic mechanisms, curbs inflammatory edema, and is antipyretic in nature.

A Saudi Arabian Public Health Perspective of Tuberculosis

Tuberculosis is a global health challenge due to its spreading potential. The Kingdom of Saudi Arabia (KSA) faces a challenge in the spread of tuberculosis from migrant workers, but the foremost threat is the huge number of pilgrims who travel to visit sacred sites of the Islamic world located in the holy cities of Makkah and Al Madina. Pilgrims visit throughout the year but especially in the months of Ramadan and Zul-Hijah. The rise of resistance in Mycobacterium tuberculosis is an established global phenomenon that makes such large congregations likely hotspots in the dissemination and spread of disease at a global level. Although very stringent and effective measures exist, the threat remains due to the ever-changing dynamics of this highly pathogenic disease. This overview primarily highlights the current public health challenges posed by this disease to the Saudi health system, which needs to be highlighted not only to the concerned authorities of KSA, but also to the concerned global quarters since the pilgrims and migrants come from all parts of the world with a majority coming from high tuberculosis-burdened countries.

769 Analysing the Change – Outcomes and Benefits of Clinic-Based Removal of Renal Transplant Stents Using A Disposable Cystoscope

Introduction

Literature is chock-full of data regarding the “when” of ureteric stent removal after renal transplantation. We have attempted to address the “who”, “where” and “how” components.

Method

The Isiris disposable scope was used to remove renal allograft stents from 383 patients in the Transplant Clinic from June 2018 to April 2020. An advanced nurse practitioner was trained in the procedure. The learning curve, incidence of complications, benefits and cost implications were studied, and compared with the cohort having stent removal with a traditional flexible cystoscope in theatres.

Results

There were 14 failures necessitating theatre removal. The transplant-to-stent-removal interval was significantly lower in the clinic cohort with a mean of 38.80 days (95%CI 37.26–40.34) to 46.55 days in theatres (95%CI 43.47–49.62). 11 patients had urgent bedside stent removal. The service was delivered independently by the nurse for 5.3% of the patients in June 2018 and progressed to over 80% by April 2019. Estimated net gain was £919/patient.

Conclusions

Moving transplant ureteric stent removals from a resource intensive all-day process in theatres to a one-stop event in the clinic is a safe and economical model that can streamline flow in patient pathway and inculcate new skills in other members of the multidisciplinary team.

Implementation and Evaluation of a Social Media-Based Communication Strategy to Enhance Employee Engagement: Experiences From a Children's Hospital, Pakistan

Social media can complement organizational communication strategy which is integral to employee engagement. However, successful case studies which can allow replication are limited. The objective of the study is to describe the design, implementation, and evaluation of a social media-based communication strategy in a tertiary care hospital in Pakistan. The leadership of the pediatric service line developed an intervention plan to engage the employees with the newly reframed vision to improve patient and family experience. An online communication platform—Facebook page—was created for all employees of the pediatric service line. The strategy to influence employees was based on Cialdini's six principles of persuasion. Implementation of the strategy between October 2017 and December 2019 was evaluated for reach, discussion themes, and outcomes using the framework by Murdough (2009). Quantitative indicators included total posts, mean comments, and reactions per post. Posts were qualitatively analyzed with an emergent approach for insights into the discussion. The analysis revealed a total of 9,085 posts, with mean reactions per post of 8.4, mean comments of 7.2, and active viewership by 90% members on average. In terms of post types, photos were the highest (4,779), while videos were the lowest (1,163). Qualitative analysis indicated 54% of the posts were of the theme “inspirational and thought provoking,” while the greatest engagement was generated on the theme “challenges and solution.” The authors conclude that the strategy was successfully implemented to maintain active membership, engage employees in meaningful conversations, and have them express intent to execute quality improvement projects.

A novel gabapentin analogue assuages neuropathic pain response in chronic sciatic nerve constriction model in rats

Gabapentin (GBP) is an established drug that has been used in the management of symptoms of neuropathy but it is associated with unwanted side effects such as sedation and motor incoordination. The goal of the study was to find out a drug with greater efficacy and safety for the treatment of neuropathic pain. Our previously synthesized GABA analogue (Gabapentsal, GPS) was tested (25-100 mg/kg, i.p) in chronic constriction injury (CCI) induced nociceptive model of static allodynia, dynamic allodynia, thermal hyperalgesia, mechanical hyperalgesia and cold allodynia in rats (Sprague Dawley). Open field and rotarod tests were performed to assess the impact of GPS on the motor performance of the animals. GBP (100 mg/kg, i.p) was used as a standard for comparison. GPS dose dependently reduced static (P <0.001) and dynamic allodynia (P <0.001), thermal hyperalgesia (P <0.001), mechanical hyperalgesia (P < 0.001) and cold allodynia (P < 0.001). In comparison to GBP, GPS failed to alter any significantly the motor performance of rats in both the open field and rotarod assays. These results suggest that GPS is effective in alleviating nociception in CCI neuropathic pain model but free from the side effect of motor discoordination seen in the treatment with GBP. In conclusion, GPS may prove to be a prospectively more effective and safer option in the management of neuropathic syndromes.

Promising Lead Compounds in the Development of Potential Clinical Drug Candidate for Drug-Resistant Tuberculosis

According to WHO report, globally about 10 million active tuberculosis cases, resulting in about 1.6 million deaths, further aggravated by drug-resistant tuberculosis and/or comorbidities with HIV and diabetes are present. Incomplete therapeutic regimen, meager dosing, and the capability of the latent and/or active state tubercular bacilli to abide and do survive against contemporary first-line and second line antitubercular drugs escalate the prevalence of drug-resistant tuberculosis. As a better understanding of tuberculosis, microanatomy has discovered an extended range of new promising antitubercular targets and diagnostic biomarkers. However, there are still no new approved antitubercular drugs of routine therapy for several decades, except for bedaquiline, delamanid, and pretomanid approved tentatively. Despite this, innovative methods are also urgently needed to find potential new antitubercular drug candidates, which potentially decimate both latent state and active state mycobacterium tuberculosis. To explore and identify the most potential antitubercular drug candidate among various reported compounds, we focused to highlight the promising lead derivatives of isoniazid, coumarin, griselimycin, and the antimicrobial peptides. The aim of the present review is to fascinate significant lead compounds in the development of potential clinical drug candidates that might be more precise and effective against drug-resistant tuberculosis, the world research looking for a long time.

Metered Dose Inhaler Technique: A Priority Catch for Physicians

BACKGROUND

Asthma is a non-curable but preventable disease that can be controlled by a proper approach. Inhalational route is considered to be one of the fastest, non-invasive course for the management of asthma. Despite its importance, compliance towards proper inhalational technique remains quite low. Thus, United Kingdom guidelines and Global Strategy for Asthma Management and Prevention (GINA) recommend regular assessment of inhaler techniques in all asthma patients.

OBJECTIVE

To evaluate the inhalational technique of asthma patients visiting out-patient departments of public sector tertiary care hospitals of Rawalpindi and correlate with various demographic factors.

METHODS

A cross-sectional study was conducted on a total of 209 respondents visiting the outpatient department of public sector hospitals in Rawalpindi. Asthmatic patients were included via a non-probability consecutive sampling technique and were assessed for inhaler techniques via a structured checklist. Statistical data were analyzed using IBM Statistical Package for Social Sciences (SPSS®), version 25.0 (IBM Corp., Armonk, NY, USA).

RESULTS

Two hundred and nine asthma patients were included. Only 10% of patients demonstrated the correct inhaler technique. Continuing inhaling till lungs are full, holding breath for five to 10 seconds, and breathing out slowly after using the inhaler were most poorly followed.

CONCLUSION

Most asthma patients are using poor inhalation technique, risking sub-optimal drug delivery and inadequate effects. Hence, it is the need of the hour to focus on patient training and education.

The Resurgence of Measles Infection and its Associated Complications in Early Childhood at a Tertiary Care Hospital in Peshawar, Pakistan

Measles infection is of substantial interest to immunologists due to its paradoxical interaction with the immune system. After the acquisition of the measles infection, secondary infection plays a pivotal role in measles-related deaths. A cross-sectional study conducted between December 2018 and July 2019 is presented here. A total of one hundred children of both genders presented with measles complications were included following WHO criteria. Measles confirmation was done by quantitative determination of anti-measles antibodies (IgM) in patients’ sera while patient-related demographic data, vaccination status, and other clinical information were obtained on a separate form. The number of female patients (52%) slightly exceeded the number of males (48%). 43% of patients’ parents were illiterate, and half of the patients (50%) were from a poor background. The majority of children (76%) who presented with the complications did not receive a measles vaccine. 56% of children were breastfed while 58% received vitamin A supplements but developed complications. The elevated levels of anti-measles IgM were observed in 77% of cases. In both genders, the major complications were pneumonia, lower respiratory tract infection (LRTI), acute diarrhea, diarrhea and LRTI, pneumonia and diarrhea, otitis media and pneumonia, myocarditis and LRTI, and pneumothorax. The majority of the infected children (n = 48) under 12 months of age had associated complications. It has been observed that the measles virus strikes early age children in the northwestern region of Pakistan, which is an alarming situation and is associated with the aforementioned complications, especially in unvaccinated children. Anti-measles IgM is an important serological parameter for early diagnosis of measles infection.

Chemical vapor transport growth of bulk black phosphorus single crystals

Recent progress in growth of bulk black phosphorus single crystal by CVT method has been briefly reviewed with the emphasis on reaction system, nucleation and growth mechanism as well as advancement in growth of doped BP bulk single crystal.

Free-Standing CoO-POM Janus-like Ultrathin Nanosheets

A single-step solution-based strategy is used to obtain 2D Janus-like free-standing ultrathin nanosheets build from two structurally unrelated species, that is, polyoxomolybdate (POM) and CoO. A controlled 2D-to-1D morphological transition was achieved by judiciously adjusting the solvent choice. These POM-CoO heterostructures can behave as an ideal catalyst for the epoxidation of styrene. Benefiting from their amphiphilic nature, these 2D POM-CoO nanosheets have also been used as surfactant to emulsify immiscible solvents. It is anticipated that structurally diverse polyoxometalates will offer promise as design elements for variety of structurally and compositionally tunable van der Waals integrated heteromaterials having a broad range applications.

Prevalence of Hepatitis C Virus Genotypes in Pakistan: Current Scenario and Review of Literature

Hepatitis C virus (HCV) is a major public health concern globally, resulting in liver-related complications. Approximately 6% population of Pakistan is infected with HCV. HCV is error prone, due to which it is classified into 7 genotypes and 67 subtypes. HCV genotype determination is critical for treatment and therapy response. In this study, 3,539 samples were collected from 2015 to 2019 from all over Punjab. RNA was extracted from samples using QIA Amp Viral RNA MINI kit (Qiagen, Germany) and viral genotyping was performed. Furthermore, a systemized literature search (2009-2018) was done to analyze the HCV genotype distribution pattern in Pakistan. In Punjab, genotype 3a (86.46%) is most prevalent, followed by untypable (7.17%) and genotype 1a (3.84%) and 3b (1.04%). Mixed genotype constitutes only 0.67% of total infections. Genotype 2a, 2b, 3c, and 4 were found to be rare. Data available from literature review when compiled showed that HCV genotype 3a (58.16%) was predominant in Pakistan, followed by genotypes 3b (9.05%), 2a (6.70%), 1a (6.22%), and 1b (2.39%). The frequency of mixed genotypes was found to be 4% and 12% of untypable HCV variants. This study highlights the HCV genotype distribution pattern in different regions of Pakistan. Therapy response and disease management depend on genotype, so HCV genotype determination is crucial. In Pakistan, the most prevalent genotype is 3a, followed by untypable genotype. Both interferon and sofosbuvir are effective against genotype 3a, but treatment with sofosbuvir has comparatively high sustained virological response, less adverse effects, and more tolerability.

Gender based differences in patients of poisoning managed at a Medical Unit

Poisoning is a nationwide hazard. This was a cross-sectional observational study carried out from 2016 to 2017 focused on indoor patients of poisoning at the District Headquarters Hospital, Rawalpindi. We studied the gender-based differences in patients of poisoning to decipher information related to poisoning in which we noted eight variables. For the study 180 patients were included of which 54.4% were males and the rest females. Married patients outnumbered unmarried patients - 70.7% females and 50.2% males. The mean age was 30±12.9 and 27±12.6 respectively. Patients were predominantly of urban residence (56.1% & 52.4% respectively). Deliberate self-poisoning (DSP) was the most common intent among both genders, 81.7% in females and 72.4% among the males in contrast to accidental poisoning which was 23.5% in males and 18. 3 % in females. Aluminum-phosphide, organophosphates, snakebite and corrosive intake were the most common form of poisonings. Unknown causes of poisoning were found significantly more in males (P=0.001), while corrosive intake was more common among the females (P=0.002). Mean duration of hospitalisation for all was 4.22±3.5 days. Out of the 180 patients of poisoning, 18% expired as a result. Conclusively, among married women poisoning is more significant, homicidal poisoning is exclusive to males and corrosive poisoning is predominant in females.

Secondary Fahr’s Disease: A Consequence of Post-Thyroidectomy Hypoparathyroidism

Objective

The objective of this case report is to emphasize the importance of considering uncommon conditions like Fahr’s disease in the differential diagnosis of seizures and cognitive impairment, especially in patients with a history of thyroidectomy.

Material and Methods

A 56-year-old woman who had undergone subtotal thyroidectomy 25 years previously presented with movement disorder and cognitive impairment secondary to hypoparathyroidism. A CT scan of the brain showed pathognomonic bilateral calcification in the basal ganglia, thalamus and cerebellar nuclei.

Result

The patient was diagnosed with Fahr’s disease caused by post-thyroidectomy hypoparathyroidism and successfully managed with oral calcium, carbidopa/levodopa and haloperidol.

Conclusion

We recommend the routine use of CT scanning in the long-term follow-up of post-thyroidectomy patients.

LEARNING POINTS

Cloning the λ Switch: Digital and Markov Representations

The lysis-lysogeny switch in E. coli due to infection from lambda phage has been extensively studied and explained by scientists of molecular biology. The bacterium either survives with the viral strand of deoxyribonucleic acid (DNA) or dies producing hundreds of viruses for propagation of infection. Many proteins transcribed after infection by λ phage take part in determining the fate of the bacterium, but two proteins that play a key role in this regard are the cI and cro dimers, which are transcribed off the viral DNA. This paper presents a novel modeling mechanism for the lysis-lysogeny switch, by transferring the interactions of the main proteins, the lambda right operator and promoter regions and the ribonucleic acid (RNA) polymerase, to a finite state machine (FSM), to determine cell fate. The FSM, and thus derived is implemented in field-programmable gate array (FPGA), and simulations have been run in random conditions. A Markov model has been created for the same mechanism. Steady state analysis has been conducted for the transition matrix of the Markov model, and the results have been generated to show the steady state probability of lysis with various model values. In this paper, it is hoped to lay down guidelines to convert biological processes into computing machines.

Case of reversible diabetes mellitus in the setting of benign Pheochromocytoma

Pheochromocytomas have been shown to impair glucose tolerance and, rarely, to precipitate overt diabetes mellitus. We report here a case of a large pheochromocytoma in a woman with a recent diagnosis of diabetes mellitus that proved difficult to control despite high-dose insulin therapy who had complete resolution of her hyperglycemia following adrenalectomy. Her dramatic presentation demonstrates the need to consider this etiology in patients with new-onset insulin resistance and hypertension.

Dexibuprofen nanocrystals with improved therapeutic performance: fabrication, characterization, in silico modeling, and in vivo evaluation

Background

The aim of this study was to prepare and evaluate the impact of polymers on fabricating stable dexibuprofen (Dexi) nanocrystals with enhanced therapeutic potential, using a low energy, anti-solvent precipitation method coupled with molecular modelling approach.

Methods

Dexi nanocrystals were prepared using antisolvent precipitation with syringe pump. Crystallinity of the processed Dexi particles was confirmed using differential scanning calorimetry and powdered X-ray diffraction and transmission electron microscopy. Dissolution of Dexi nanocrystals was compared with raw Dexi and marketed tablets. Molecular modelling study was coupled with experimental studies to rationalise the appropriate polymers for stable Dexi nanocrystals. Antinociceptive study was carried out using balb mice.

Results

Combinations of hydroxypropyl methylcellulose (HPMC)-polyvinyl pyrrolidone (PVP) and HPMC-Eudragit (EUD) were shown to be very effective in producing stable Dexi nanocrystals with particle sizes of 85.0±2.5 nm and 90±3.0 nm, and polydispersity of 0.179±0.01, 0.182±0.02, respectively. The stability studies conducted for 90 days demonstrated that nanocrystals stored at 2°C-8°C and 25°C were more stable than those at 40°C. The maximum recovery of Dexi nanocrystals was observed from the formulations using the combination of HPMC-PVP and HPMC-EUD, which equated to 98% and 94% of the nominal active drug content respectively. The saturation solubility of the Dexi nanocrystals was substantially increased to 270.0±3.5 μg/mL compared to the raw Dexi in water (51.0±2.0 μg/mL) and stabilizer solution (92.0±3.0 μg/mL). Enhanced dissolution rate (P<0.05) was observed for the Dexi nanocrystals compared to the unprocessed drug substance and marketed tablets. Dexi nanocrystals produced the analgesic effect at much lower doses (5 mg/kg) than that of control standard, diclofenac sodium (20 mg/kg) and Dexi counterparts (40 mg/kg).

Conclusion

HPMC-PVP and HPMC-EUD were found the best polymer combination to stabilise Dexi nanocrystals. The Dexi nanocrystals exhibited significant dissolution, solubility and analgesic effect compared to the raw Dexi and the control standard diclofenac sodium.

Berberine nanoparticles with enhanced in vitro bioavailability: characterization and antimicrobial activity

BACKGROUND

Berberine is an isoquinoline alkaloid widely used in Ayurveda and traditional Chinese medicine to treat illnesses such as hypertension and inflammatory conditions, and as an anticancer and hepato-protective agent. Berberine has low oral bioavailability due to poor aqueous solubility and insufficient dissolution rate, which can reduce the efficacy of drugs taken orally. In this study, evaporative precipitation of nanosuspension (EPN) and anti-solvent precipitation with a syringe pump (APSP) were used to address the problems of solubility, dissolution rate and bioavailability of berberine.

METHODS

Semi-crystalline nanoparticles (NPs) of 90-110 nm diameter for APSP and 65-75 nm diameter for EPN were prepared and then characterized using differential scanning calorimetry (DSC) and X-ray powder diffractometry (XRD). Thereafter, drug content solubility and dissolution studies were undertaken. Berberine and its NPs were evaluated for their antibacterial activity.

RESULTS

The results indicate that the NPs have significantly increased solubility and dissolution rate due to conversion of the crystalline structure to a semi-crystalline form.

CONCLUSION

Berberine NPs produced by both APSP and EPN methods have shown promising activities against Gram-positive and Gram-negative bacteria, and yeasts, with NPs prepared through the EPN method showing superior results compared to those made with the APSP method and the unprocessed drug.

Bioactive Steroids and Saponins of the Genus Trillium

The species of the genus Trillium (Melanthiaceae alt. Trilliaceae) include perennial herbs with characteristic rhizomes mainly distributed in Asia and North America. Steroids and saponins are the main classes of phytochemicals present in these plants. This review summarizes and discusses the current knowledge on their chemistry, as well as the in vitro and in vivo studies carried out on the extracts, fractions and isolated pure compounds from the different species belonging to this genus, focusing on core biological properties, i.e., cytotoxic, antifungal and anti-inflammatory activities.

Bioactive Steroids and Saponins of the Genus Trillium

The species of the genus Trillium (Melanthiaceae alt. Trilliaceae) include perennial herbs with characteristic rhizomes mainly distributed in Asia and North America. Steroids and saponins are the main classes of phytochemicals present in these plants. This review summarizes and discusses the current knowledge on their chemistry, as well as the in vitro and in vivo studies carried out on the extracts, fractions and isolated pure compounds from the different species belonging to this genus, focusing on core biological properties, i.e., cytotoxic, antifungal and anti-inflammatory activities.

Phosphorene-directed self-assembly of asymmetric PS-b-PMMA block copolymer for perpendicularly-oriented sub-10 nm PS nanopore arrays

Few-layer black phosphorus, also known as phosphorene, is a new two-dimensional material which is of enormous interest for applications, mainly in electronics and optoelectronics. Herein, we for the first time employ phosphorene for directing the self-assembly of asymmetric polystyrene-block-polymethylmethacrylate (PS-b-PMMA) block copolymer (BCP) thin film to form the perpendicular orientation of sub-10 nm PS nanopore arrays in a hexagonal fashion normal to the interface. We experimentally demonstrate that none of the PS and PMMA blocks exhibit preferential affinity to the phosphorene-modified surface. Furthermore, the perpendicularly-oriented PS nanostructures almost stay unchanged with the variation of number of layers of few-layer phosphorene nanoflakes between 15-30 layers. Differing from the neutral polymer brushes which are widely used for chemical modification of the silicon substrate, phosphorene provides a novel physical way to control the interfacial interactions between the asymmetric PS-b-PMMA BCP thin film and the silicon substrate. Based on our results, it is possible to build a new scheme for producing sub-10 nm PS nanopore arrays oriented perpendicularly to the few-layer phosphorene nanoflakes. Furthermore, the nanostructural microdomains could serve as a promising nanolithography template for surface patterning of phosphorene nanoflakes.

Risk factors associated with multi-drug-resistant Acinetobacter baumannii nosocomial infections at a tertiary care hospital in Makkah, Saudi Arabia - a matched case-control study

Objective To determine risk factors for multi-drug-resistant Acinetobacter baumannii (MDR-AB) nosocomial infections in intensive care units in a tertiary care hospital, Makkah, Saudi Arabia. Methods We performed a hospital-based, matched case-control study in patients who were admitted to Al Noor Specialist Hospital between 1 January 2012 and 31 August 2012. The study included cases of A. baumannii nosocomial infection and controls without infection. Controls were matched to cases by age and ward of admission. Results The most frequent site of infection was the respiratory tract (77.3%). Susceptibility to antimicrobial MDR-AB was 92.0% for ceftazidime and ciprofloxacin, while it was 83.3% for imipenem, 83.0% for trimethoprim, 79.0% for amikacin, and 72.7% for gentamicin. Multiple logistic regression of risk factors showed that immunosuppression (OR = 2.9; 95% CI 1.5-5.6; p = 0.002), clinical outcome (OR = 0.4; 95% CI 0.3-0.9; p = 0.01), invasive procedures (OR = 7.9; 95% CI 1.8-34.2; p = 0.002), a central venous catheter (OR = 2.9; 95% CI 1.5-5.6; p = 0.000), and an endotracheal tube (OR = 3.4; 95% CI 1.6-7.3; p = 0.001) were associated with MDR-AB. Conclusions Acinetobacter nosocomial infections are associated with admission to the ICU (Intensive care unit) and exposure to invasive procedures.

Fabrication, characterization and in vitro evaluation of silibinin nanoparticles: an attempt to enhance its oral bioavailability

Background

Silibinin has gained in importance in the past few decades as a hepatoprotector and is used widely as oral therapy for toxic liver damage, liver cirrhosis, and chronic inflammatory liver diseases, as well as for the treatment of different types of cancers. Unfortunately, it has low aqueous solubility and inadequate dissolution, which results in low oral bioavailability.

Materials and methods

In this study, nanoparticles (NPs) of silibinin, which is a hydrophobic drug, were manufactured using two cost-effective methods. Antisolvent precipitation with a syringe pump (APSP) and evaporative precipitation of nanosuspension (EPN) were used. The prepared NPs were characterized using different analytical techniques such as scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and X-ray powder diffractometry (XRD) and were sifted for their bioavailability through in vitro dissolution and solubility studies. Moreover, the prepared NPs were evaluated for antimicrobial activity against a battery of bacteria and yeast.

Results

DSC and XRD studies indicated that the prepared NPs were amorphous in nature, with more solubility and dissolution compared to the crystalline form of this drug. NPs prepared through the EPN method had better results than those prepared using the APSP method. Antimicrobial activities of the NPs were improved compared to the unprocessed drugs, while having comparable activities to standard antimicrobial drugs.

Conclusion

Results indicate that the NPs have significantly increased solubility, dissolution rate, and antimicrobial activities due to the conversion of crystalline structure into amorphous form.