Risk of Covid-19 infection during endoscopy: Efficacy of personal protective equipment (PPE) in protecting health professionals.

OBJECTIVES: To correlate compliance to personal protective equipment (PPE) protocols and risk of exposure to SARS-COV-2 infection in endoscopy staff. METHODS: We included 85 endoscopic procedures performed at Lahore General Hospital from May to July 2020. Standard operating procedures (SOPs) were implemented for patient selection, risk stratification and personal protective equipment (PPE) use for endoscopy staff. Patient and endoscopy staff were followed for Covid-19 infection. PPE scores for staff and Covid-19 positivity on follow-up were correlated using student's t test. RESULTS: Following 85 procedures included, 2 (2.3%) patients became Covid-19 positive. PPE score was <9 in 5 (5.8%) procedures for endoscopist and Covid-19 developed in 2 (2.3%) of them, PPE score was <9 during 19 (22.3%) procedures in 1st assistant and 9 (10.5%) developed infection and for 2nd assistant PPE score was <9 in 19(22.3%) endoscopies and 5 (5.9%) tested positive for covid-19. Infectivity of endoscopy staff was 6.2%. Association between PPE score and risk of Covid-19 was not significant. (p value 0.51 for endoscopist, 0.10 for 1st assistant and 0.09 for 2nd assistant). CONCLUSION: Compliance of SOPs for infection control reduces risk of acquiring Covid-19 infection during endoscopy. Proper use of PPE is effective for safety of endoscopy staff.

Construction and recombinant expression of Pseudomonas aeruginosa truncated exotoxin A in Escherichia coli.

Pseudomonas aeruginosa exotoxin A (PE) is a bacterial toxin composed of three domains namely: cell binding, translocation and enzymatic domain. The cytotoxic activity of PE is attributed to the enzymatic domain, which inhibits protein synthesis through ADP-ribosylation of EF-2. PE can be genetically modified to fight cancer. In this regard, a truncated and modified form of PE was produced that could be used for more potent immunotoxins. This modified form termed PE38KDEL was completely devoid of cell binding domain and parts of translocation domain II and Ib which are reported to be inessential for cytotoxicity of the toxin. The resultant expressed protein consisted of the essential translocation domain II and catalytic subunit (domain Ib, III). The deletions in the exotoxin A gene for truncated protein production were made via overlapping PCR extension. The amplicon was cloned in pTZ57r-T vector for DNA works and sub cloned in pET22b expression vector.  It is demonstrated here that PE38KDEL can be expressed in huge quantities in Escherichia coli by using the recombinant vector PE38KDEL/pET under control of T7 promoter and E. coli host strain BL21 (DE3) CodonPlus. The protein expression was optimized at 0.5 mM IPTG concentration for induction as soon as the OD600 nm reached 0.6 with 6 hours of post induction culturing at 37°C.  The recombinant protein was expressed both as soluble and inclusion body forms however the expression of the soluble form was more pronounced.

Biased expression, under the control of single promoter, of human interferon α-2b and Escherichia coli methionine amino peptidase genes in E. coli, irrespective of their distance from the promoter.

Human interferon α-2b and Escherichia coli methionine amino peptidase genes were cloned independently as well as bicistronically in expression plasmid pET-21a (+). Production of human interferon α-2b was comparable to that of E. coli methionine amino peptidase when these genes were expressed independently in E. coli BL21-CodonPlus (DE3)-RIL. However, human interferon α-2b was produced in a much less amount whereas there was no difference in the production of methionine amino peptidase when the encoding genes were expressed bicistronically. It is important to note that human interferon α-2b was the first gene in order, after the promoter and E. coli methionine amino peptidase was the next with a linker sequence of 27 nucleotides between them.

Studies on the expression and processing of human proinsulin derivatives encoded by different DNA constructs.

A synthetic gene encoding human proinsulin, containing Escherichia coli preferred codons, with an additional N-terminal methionine, was used for the expression, of M-proinsulin and construction of nine derivatives. No improvement in expression was noted, relative to that of M-proinsulin, when the 5'- of the gene was appended to codons for seven amino acids of a well expressed E. coli protein (threonine dehydrogenase), or the constructs contained multiple copies of the proinsulin gene. That in the latter constructs only the gene adjacent to the prometer sequence is expressed, was shown by a construct containing a proinsulin gene followed by that for interferon α-2b. With the latter construct, the proinsulin was, predominantly, expressed. The availability of data on the constructs prompted, subjecting these to analysis by two models designed to predict the expression of proteins from the sequences, of putative mRNA, around the start of translation but no significant relationship was noted. In all cases the proteins were expressed as inclusion bodies, which were refolded to give products of desired masses and successfully converted into insulin derivatives. Of all the constructs containing a trypsin sensitive site before phenylalanine (F), the N-terminal sequence, MKR↓F, was most efficiently processed, by a cocktail of trypsin and buffalo carboxypeptidase B, to give insulin with the removal of the N-terminus linker as well as the C-peptide in a single step, without cleaving the trypsin sensitive K(29)T(30) peptide bond.

Developing and piloting an online course on osteoporosis using a multidisciplinary multi-institute approach- a cross-sectional qualitative study.

INTRODUCTION: Postgraduate medical trainees (PGs) in developing nations face various educational hurdles due to limited access to quality resources and training facilities. This study aimed to assess the effectiveness of e-learning, particularly Massive Open Online Courses (MOOCs), within postgraduate medical education. It involved the development of a customized online course focused on osteoporosis for PGs and an examination of their perspectives and preferences concerning online learning methods like Virtual Learning Environment (VLE) platforms. METHODS: The study was conducted from January 2018 to December 2020. A multi-institutional, multidisciplinary team was assembled to design an osteoporosis course on the VLE platform. PGs (n = 9) from diverse disciplines and institutions were selected with informed consent. Focus group discussions (FGDs) among these PGs identified their preferences for the online course, which subsequently guided the development of the MOOC. The modular MOOC comprised recorded micro-lectures, flashcards, videos, case challenges, and expert interviews. The educational impact of the VLE was assessed using pre- and post-module tests among the participants, and their perceptions of the PGs and course facilitators were gathered via an online survey. RESULTS: The study identified the involvement of PGs in the course design process as beneficial, as it allowed for content customization and boosted their motivation for peer-to-peer learning. During the FGDs, PGs expressed a strong preference for flexible learning formats, particularly short downloadable presentations, and micro-lectures. They also identified challenges related to technology, institutional support, and internet connectivity. In the subsequently customized MOOC course, 66% of PGs (n = 6) attempted the pre-test, achieving a mean score of 43.8%. Following the VLE module, all PGs (n = 9) successfully passed the end-of-module test, averaging a score of 96%, highlighting its impact on learning. The majority (n = 8, 88.9%) agreed that the course content could be applied in clinical practice, and 66.7% (n = 6) expressed extreme satisfaction with the learning objectives and content. Participants favoured end-of-module assessments and the use of best-choice questions for evaluation. CONCLUSION: This study highlights the importance of virtual learning, particularly MOOCs, in addressing the educational challenges faced by developing nations. It emphasizes the need for tailored online courses that cater to the preferences and requirements of PGs. The findings suggest that MOOCs can foster collaboration, networking, and opportunities for professional development, and interdisciplinary collaboration among faculty members can be a key strength in course development. This research provides valuable insights for educators, institutions, and e-learning developers seeking to enhance their teaching methodologies and establish accessible educational environments in the digital age.

Efficient drug delivery potential and antimicrobial activity of biocompatible hydrogels of dextrin/Na-alginate/PVA.

Ceftriaxone sodium belongs to the third-generation cephalosporin group and is used intramuscular and intravenous route as a broad-spectrum antibiotic. This research aims to prepare biocompatible hydrogels for targeted delivery of ceftriaxone sodium by parental route. Different proportions of polymers (natural and synthetic) in the presence of cross-linker were synthesized by solvent casting method. Ceftriaxone sodium was loaded in hydrogels in different concentrations and its drug release behavior was evaluated along with swelling and biodegradation analysis. The characterization of hydrogel was done by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) to analyze surface morphology and functional groups involved in the formation of dextrin/Na-alginate/PVA hydrogels loaded with the drug. Thermogravimetric analysis (TGA) was confirmed by thermal stability and degradation pattern of loaded and unloaded hydrogels. The drug-loaded samples presented promising antimicrobial activity against S. aureus and P. multocida and their cytotoxic nature was also studied. Drug release analysis using simulated intestinal fluid (SIF) and phosphate buffer saline(PBS) for the circulatory system shows the consistent release of the drug. The findings unveiled the development of a biocompatible and innovative hydrogel, which has potential advantages for biomedical application, particularly in enhancing the therapeutic efficacy of ceftriaxone sodium drug.

Characterization of a thermostable and alkaline xylanase from Bacillus sp. and its bleaching impact on wheat straw pulp.

Delignification efficacy of xylanases to facilitate the consequent chemical bleaching of Kraft pulps has been studied widely. In this work, an alkaline and thermally stable cellulase-less xylanase, derived from a xylanolytic Bacillus subtilis, has been purified by a combination of gel filtration and Q-Sepharose chromatography to its homogeneity. Molecular weight of the purified xylanase was 61 kDa by SDS-PAGE. The purified enzyme revealed an optimum assay temperature and pH of 60°C and 8.0, respectively. Xylanase was active in the pH range of 6.0-9.0 and stable up to 70°C. Divalent ions like Ca(2+), Mg(2+) and Zn(2+) enhanced xylanase activity, whereas Hg(2+), Fe(2+), and Cu(2+) were inhibitory to xylanase at 2 mM concentration. It showed K ( m ) and V ( max ) values of 9.5 mg/ml and 53.6 µmol/ml/min, respectively, using birchwood xylan as a substrate. Xylanase exhibited higher values of turn over number (K (cat)) and catalytic efficiency (K (cat)/K (m)) with birchwood xylan than oat spelt xylan. Bleach-boosting enzyme activity at 30 U/g dry pulp displayed the optimum bio-delignification of Kraft pulp resulting in 26.5% reduction in kappa number and 18.5% ISO induction in brightness at 55°C after 3 h treatment. The same treatment improved the pulp properties including tensile strength and burst index, demonstrating its potential application in pre-bleaching of Kraft pulp.

Risk Assessment of Hepatocellular Carcinoma with Aflatoxin B1 Exposure in Edible Oils.

Contamination of edible oils with aflatoxins (AFs) is a universal issue due to the detrimental effects of aflatoxins on human health and the fact that edible oils are a major source of fungal growth, particularly storage fungi (Aspergillus sp.). The objective of this study was to assess aflatoxin B1 (AFB1) in edible oil used in fried food in order to determine the risk of cancer from AFB1 exposure through cooked food using the FAO/WHO's and EFSA's margin of exposure (MOE) quantitative liver cancer risk approaches. Using Mycosep 226 columns and HPLC-FLD, 100 samples of cooking oils (soybean, canola, and sunflower oil) from different food points were analyzed for contamination with aflatoxins. Of all the samples tested, 89% were positive for total aflatoxins and AFB1, with 65% indicating AF concentrations beyond permitted levels. Canola oil was found to contain higher levels of AFB1 and AFs than soybean and sunflower oil. Almost 71 percent of canola oil samples (range of 54.4-281.1 µg/kg) were contaminated with AF levels higher than the proposed limits of the European Union (20 µg/kg). The consumption of canola oil samples used in fried foods had MOE values that were significantly lower as compared to sunflower and soybean oils, indicating that risk reduction is feasible. Additionally, compared to soybean and sunflower oil, canola oil exhibited a greater threat of liver cancer cases linked to AFB1 exposure (17.13 per 100,000 males over 35 and 10.93 per 100,000 females over 35). Using a quantitative liver cancer approach, health risk valuation demonstrated that males and females over the age of 35 are at significant risk of developing liver cancer. The health risk assessment exposed that the males and female over the age of 35 are at considerable risk of liver cancer by using a quantitative liver cancer approach. The innovation of this study lies in the fact that no such study is reported related to liver cancer risk evaluation accompanied with AFB1 exposure from consumed edible oil. As a result, a national strategy must be developed to solve this problem so that edible oil products are subjected to severe regulatory examination.

Galerkin finite element analysis for magnetized radiative-reactive Walters-B nanofluid with motile microorganisms on a Riga plate.

In order to understand the characteristics of bio-convection and moving microorganisms in flows of magnetized Walters-B nano-liquid, we developed a model employing Riga plate with stretchy sheet. The Buongiorno phenomenon is likewise employed to describe nano-liquid motion in the Walters-B fluid. Expending correspondence transformations, the partial differential equation (PDE) control system has been transformed into an ordinary differential equation (ODE) control system. The COMSOL program is used to generate mathematical answers for non-linear equations by employing the Galerkin finite element strategy (G-FEM). Utilizing logical and graphical metrics, temperature, velocity, and microbe analysis are all studied. Various estimates of well-known physical features are taken into account while calculating nanoparticle concentrations. It is demonstrated that this model's computations directly relate the temperature field to the current Biot number and parameter of the Walters-B fluid. The temperature field is increased to increase the approximations of the current Biot number and parameter of the Walters-B fluid.

Development of a virtual classroom for pre-analytical phase of laboratory medicine for undergraduate medical students using the Delphi technique.

BACKGROUND: Amongst the pre-analytical, analytical, and post-analytical phase of laboratory testing, pre-analytical phase is the most error-prone. Knowledge gaps in understanding of pre-analytical factors are identified in the clinical years amongst undergraduate students due to lack of formal teaching modules on the pre-analytical phase. This study was conducted to seek experts' consensus in Clinical Chemistry on learning objectives and contents using the Delphi technique with an aim to develop an asynchronous virtual classroom for teaching pre-analytical factors of laboratory testing. METHODS: A mixed method study was conducted at the Aga Khan University. A questionnaire comprising of 16 learning objectives and their associated triggers was developed on Google Docs for developing the case vignettes. A four-point Likert Scale, which included strongly agree, agree, disagree and strongly disagree, was utilized for the learning objectives. An open-ended question was included for experts to suggest new items for inclusion. A cut off of at least 75% agreement was set to establish consensus on each item. A total of 17 Chemical Pathology faculty from 13 institutions across Pakistan were invited to participate in the first round of Delphi. Similar method of response was used in round two to establish consensus on the newly identified items suggested by the faculty in round 1. Later, the agreed-upon objectives and triggers were used to develop interactive scenarios over Moodle to concurrently test and teach medical students in a nonchalant manner. RESULTS: A total of 17 responses were received in Round 1 of the Delphi process (response rate = 100%), while 12 responses were received in Round 2 (response rate = 71%). In round 1, all 16 learning objectives reached the required consensus (≥ 75%) with no additional learning objectives suggested by the experts. Out of 75 triggers in round 1, 61 (81.3%) reached the consensus to be included while 39 were additionally suggested. In 2nd round, 17 out of 39 newly suggested triggers met the desired consensus. 14 triggers did not reach the consensus after two rounds, and were therefore eliminated. The virtual classroom developed using the agreed-upon learning objectives and triggers consisted of 20 items with a total score of 31 marks. The questions included multiple choice questions, fill in the blanks, drag and drop sequences and read-and-answer comprehensions. Specific learning points were included after each item and graphs and pictures were included for a vibrant experience. CONCLUSION: We developed an effective and interactive virtual session with expert consensus on the pre-analytical phase of laboratory testing for undergraduate medical students which can be used for medical technologist, graduate students and fellows in Chemical Pathology.

Optimizing factors for the efficient expression and purification of spao and lamb from Salmonella typhi

We optimized the expression and purification of outer membrane proteins SpaO and LamB from Salmonella typhi. We investigated various factors in the expression and purification processes, including the use of isopropyl ß-d-1 thiogalactopyranoside (IPTG), imidazole, and urea. First, PCR amplification was carried out on SpaO and LamB genes. The genes were then cloned in pTZ57R/T, and then expressed in pET28a vector and transformed into Escherichia coli BL21 (DE3). Gene insertion was confirmed by enzymatic digestion with NdeI and XhoI. Inclusion bodies expressing recombinant SpaO and LamB were induced with 200 and 400 µL 0.5 mM IPTG, respectively. The formed protein inclusion bodies were then isolated from the pellet and solubilized in IB buffer containing 8 M urea for SpaO and 6 M urea for LamB. Proteins were refolded by dialysis in 3M urea. Purified proteins with nickel-nitrilotriacetic acid affinity chromatography and eluted with buffer containing 250 mM imidazole for SpaO and 150 mM imidazole for LamB. The protein expression profiles were analyzed by SDS-PAGE, which identified the 33 and 49 kDa bands corresponding to rSpaO and rLamB. Western blotting Purification was carried out by nickel affinity resin with 250 mM and 150 mM imidazole for rSpaO and rLamB and refolded through stepwise dialysis with anti-His tag antibodies confirmed their expression. These optimized methods can be used to generate recombinant proteins for the development of future vaccines.

Microbiological Load of Ethylene Oxide Sterilized Medical Devices and its Elimination by Cobalt 60 Source.

OBJECTIVE: To determine the residing microbial flora of ethylene oxide (EtO) sterilized medical devices and optimization of safe dose of gamma radiation (Cobalt 60 source) for the complete elimination of microbial load. STUDY DESIGN: Experimental study. PLACE AND DURATION OF STUDY: Department of Biotechnology, Lahore College for Women University, Lahore, Pakistan from September 2014 to June 2015. METHODOLOGY: Thirty-six samples of EtO sterilized medical devices of same batch of three different companies were collected for this study. Isolation and enumeration of microbes were done by using different selective and differential media. Gram staining and biochemically characterization by API 20 (Bio Merieux, France) kit was done for identification of the microorganisms. The medical devices having high microbial load were sent to Pakistan Radiation Services (PARAS) for gamma irradiations at 3 different selected doses (20 KGy, 25 KGy, and 30 KGy). RESULTS: Different types of Gram positive bacteria (Staphylococcus epidermidis, Staphylococcus aureus andBacillus subtilis) were isolated from the EtO sterilized samples. Gram negative bacteria and fungi were not detected on these medical devices. Gamma irradiations results showed that 30 KGy was optimized dose for complete elimination of microbial flora on endotracheal, Nelaton, and tracheostomy tubes. CONCLUSION: Gamma radiations (Co 60 source) effectively decontaminate the microbial flora on the equipment previously sterilized by the ethylene oxide gas; and 30 KGy is the optimized dose for all these medical devices.

Process optimization for enhanced production of cellulases form locally isolated fungal strain by submerged fermentation

Cellulase has myriad applications in various sectors like pharmaceuticals, textile, detergents, animal feed and bioethanol production, etc. The current study focuses on the isolation, screening and optimization of fungal strain through one factor at a time technique for enhanced cellulase production. In current study sixteen different fungal cultures were isolated and the culture which quantitatively exhibits higher titers of cellulase activity was identified both morphologically and molecularly by 18S rDNA and designated as Aspergillus niger ABT11. Different parameters like fermentation medium, volume, temperature, pH and nutritional components were optimized. The highest CMCase and FPase activities was achieved in 100ml of M5 medium in the presence of 1% lactose and sodium nitrate at 30 oC, pH5 after 72 hours. The result revealed A. niger can be a potential candidate for scale up studies.

Association between TSH status and prevalence of miscarriages and stillbirth

Thyroid hormones play a significant role in normal human body growth. Abnormalities in thyroid stimulating hormone (TSH) levels can result in pregnancy loss due to miscarriages and intrauterine death (IUD). The objective of the study was to assess the levels of association of thyroid stimulating hormone with miscarriages and IUD. The descriptive study involving 110 samples between 18-40 years of age fulfilling inclusion criteria were sampled for TSH testing (2ml blood) after attaining their written informed consent. The mean age of participants was 29.49±4.26 year. The prevalence of hypothyroidism and hyperthyroidism was 3.64% and 2.73%, respectively. Complications like gestational hypertension, depression and oligomenorrhea were found prevalent in these females. Majority of females were taking high/low iodine than recommended iodine level (150mcg). This work shows that there is a significant association between pregnancy loss and disturbed TSH levels among pregnant females.

Bioethanol production from urban cellulosic waste employing Alcaligenes faecalis HI-1 isolated from gut of termite Heterotermes indicola

This study assessed the potential of termite gut inhabiting bacteria towards bioconversion of cellulosic waste into biofuel. Total seven bacterial isolates from the gut of Heterotermes indicola were isolated. Among all the isolates, HI-1 produced the largest zone upon primary screening. Untreated paper had more cellulose content (73.03%) than acid (0.5%) treated paper that was used as a lignocellulosic substrate for saccharification. Among all the isolates tested, glucose yield (1.08mg/mL) was high for HI-1 isolate. Several factors were considered for optimizing augmented glucose yield (8.57mg/mL) and growth (8.07×108cfu/mL), such as temperature 37°C, pH 4.5, 5% (w/v) substrate concentration, 6 % bacterial inoculum size, agitation 150 rpm with PEG 0.25 % and Ca2+ ions 0.002 g/L. Overall 8-fold increase in glucose yield was achieved. Enzyme activity of HI-1 showed higher endoglucanase 0.29 ± 0.01 (U/mL/min) and exoglucanase 0.15±0.01 (U/mL/min) activity under optimum conditions, mentioned above. temperature 37°C, pH 4.5, substrate concentration 5%, inoculum size 6%, surfactants PEG 0.01%, ions Ca2+(0.002g/L) and agitation (120 rpm). Simultaneous saccharification and fermentation (SSF) of hydrolyzed office paper yielded 5.43mg/mL bioethanol. According to 16S rRNA sequence homology, the bacterial isolate H1 was identified as Alcaligenes faecalis. Bioethanol production from office paper untreated waste proved an effective strategy. Bacteria having natural tendency towards cellulosic waste consumption are promising for bioconversion of cellulosic waste to valuable products.

Mass cultivation of various algal species and their evaluation as a potential candidate for lipid production.

Microalgae have been proposed as a promising source for biodiesel production. Focusing on algal strains for biodiesel production, efforts should be made to search new strains. Experiments were carried out to investigate the effects of growth parameters (nutrients, pH, light, aeration and temperature) and the oil percentage of eight algal strains (Chlorella sp., Cladophora sp., Hydrodictylium sp., Oedogonium sp., Oscillatoria sp., Spirogyra sp., Stigeocolonium sp., Ulothrix sp.). Results show that 6.5-7.5 is the optimum pH for the growth of all algal species. Temperature showed a greater variation (25°40°C). Ulothrix sp. gave more biomass productivity and is the most suitable strain for biodiesel production due to higher oil percentage (62%). Least biomass production was observed for Stigeocolonium sp. and least oil content was obtained from Hydrodictylium sp. It was observed that among these eight algal strains for biodiesel production, Ulothrix and Chlorella are the most promising algae species.