In-process quality control in foot-and-mouth disease vaccine production by detection of viral non-structural proteins using chemiluminescence dot blot assay

Foot-and-mouth disease (FMD) is a contagious viral disease of cloven-footed animals. Immunization with inactivated virus vaccine is effective to control the disease. Six-monthly vaccination regimen in endemic regions has proven to be effective. To enable the differentiation of infected animals from those vaccinated, non-structural proteins (NSPs) are excluded during vaccine production. While the antibodies to structural proteins (SPs) could be observed both in vaccinated and infected animals, NSP antibodies are detectable only in natural infection. Quality control assays that detect NSPs in vaccine antigen preparations, are thus vital in the FMD vaccine manufacturing process. In this study, we designed a chemiluminescence dot blot assay to detect the 3A and 3B NSPs of FMDV. It is sensitive enough to detect up to 20 ng of the NSP, and exhibited specificity as it does not react with the viral SPs. This cost-effective assay holds promise in quality control assessment in FMD vaccine manufacturing.

Exploring bi-carbazole-linked triazoles as inhibitors of prolyl endo peptidase via integrated in vitro and in silico study

A serine protease called prolyl endopeptidase (PEP) hydrolyses the peptide bonds on the carboxy side of the proline ring. The excessive PEP expression in brain results in neurodegenerative illnesses like dementia, Alzheimer's disease, and Parkinson's disease. Results of the prior studies on antioxidant activity, and the non-cytotoxic effect of bi-carbazole-linked triazoles, encouraged us to extend our studies towards its anti-diabetic potential. Hence, for this purpose all compounds 1-9 were evaluated to reveal their anti-prolyl endo peptidase activity. Fortunately, seven compounds resulted into significant inhibitory capability ranging from 26 to 63 µM. Among them six compounds 4-9 exhibited more potent inhibitory activity with IC50 values 46.10 ± 1.16, 42.30 ± 1.18, 37.14 ± 1.21, 26.29 ± 0.76, 28.31 ± 0.64 and 31.11 ± 0.84 µM respectively, while compound 3 was the least active compound in the series with IC50 value 63.10 ± 1.58 µM comparing with standard PEP inhibitor bacitracin (IC50 = 125 ± 1.50 µM). Moreover, mechanistic study was performed for the most active compounds 7 and 8 with Ki values 24.10 ± 0.0076 and 23.67 ± 0.0084 µM respectively. Further, the in silico studies suggested that the compounds exhibited potential interactions and significant molecular conformations, thereby elucidating the structural basis for their inhibitory effects.

Green synthesis of Cu-Mn co-incorporated ZnO nanoparticles for antibacterial and photocatalytic applications

The synergistic effect of bimetallic co-incorporated metal oxides have gained enormous attention due to their unique optoelectronic properties. Herein, we present the green synthesis of ZnO, Cu-incorporated ZnO, Mn-incorporated ZnO, and Cu-Mn co-incorporated nanoparticles (ZnO NPs, CuZnO NPs, MnZnO NPs, MnCuZnO NPs) for antimicrobial and photocatalytic reduction applications using corn silk extract and industrial metal wastes. The as-synthesized NPs were characterized by using UV-visible absorption spectroscopy (UV-Vis), photoluminescence (PL) spectroscopy, Fourier-transformed infrared spectroscopy (FT-IR), powdered x-ray diffraction (XRD), and scanning electron microscopy (SEM). CuZnO, MnZnO, and MnCuZnO NPs efficiently inhibited bacterial culture growth. The photocatalytic reduction activity of as-synthesized NPs against the different concentrations of 4-nitrophenol (4-NP) in water was also investigated. CuZnO and MnCuZnO nanoparticles were to be efficient photocatalysts for reducing 4-NP into 4-aminophenol (4-AP). RESEARCH HIGHLIGHTS: Green synthesis of nanomaterials by agricultural and industrial wastes Cu and Mn co-incorporated ZnO NPs have shown good photocatalysis and antimicrobial activities Green approach for waste conversion to value-added products.

Thermostable negative-marker foot-and-mouth disease virus serotype O induces protective immunity in guinea pigs

Foot-and-mouth disease (FMD) is a contagious viral disease of high economic importance, caused by FMD virus (FMDV), a positive-sense single-stranded RNA virus, affecting cloven-hoofed animals. Preventive vaccination using inactivated virus is in practice to control the disease in many endemic countries. While the vaccination induces antibodies mainly to structural proteins, the presence of antibodies to the non-structural proteins (NSP) is suggestive of infection, a criterion for differentiation of infected from vaccinated animals (DIVA). Also, there is a growing demand for enhancing the stability of the FMD vaccine virus capsid antigen as the strength of the immune response is proportional to the amount of intact 146S particles in the vaccine. Considering the need for a DIVA compliant stable vaccine, here we report generation and rescue of a thermostable and negative marker virus FMDV serotype O (IND/R2/1975) containing a partial deletion in non-structural protein 3A, generated by reverse genetics approach. Immunization of guinea pigs with the inactivated thermostable-negative marker virus antigen induced 91% protective immune response. Additionally, a companion competitive ELISA (cELISA) targeting the deleted 3A region was developed, which showed 92.3% sensitivity and 97% specificity, at cut-off value of 36% percent inhibition. The novel thermostable-negative marker FMDV serotype O vaccine strain and the companion cELISA could be useful in FMDV serotype O enzootic countries to benefit the FMD control program. KEY POINTS: • Thermostable foot-and-mouth disease virus serotype O with partial deletion in 3A. • Inactivated thermostable marker vaccine induced 91% protection in guinea pigs. • Companion cELISA based on deleted region in 3A could potentially facilitate DIVA.

Activation of STING Based on Its Structural Features

The cGAS-cGAMP-STING pathway is an important innate immune signaling cascade responsible for the sensing of abnormal cytosolic double-stranded DNA (dsDNA), which is a hallmark of infection or cancers. Recently, tremendous progress has been made in the understanding of the STING activation mechanism from various aspects. In this review, the molecular mechanism of activation of STING protein based on its structural features is briefly discussed. The underlying molecular mechanism of STING activation will enable us to develop novel therapeutics to treat STING-associated diseases and understand how STING has evolved to eliminate infection and maintain immune homeostasis in innate immunity.

Synthesis of Ni–Ag–ZnO solid solution nanoparticles for photoreduction and antimicrobial applications

ZnO is one of the most promising and efficient semiconductor materials for various light-harvesting applications. Herein, we reported the tuning of optical properties of ZnO nanoparticles (NPs) by co-incorporation of Ni and Ag ions in the ZnO lattice. A sonochemical approach was used to synthesize pure ZnO NPs, Ni–ZnO, Ag–ZnO and Ag/Ni–ZnO with different concentrations of Ni and Ag (0.5%, 2%, 4%, 8%, and 15%) and Ni doped Ag–ZnO solid solutions with 0.25%, 0.5%, and 5% Ni ions. The as-synthesized Ni–Ag–ZnO solid solution NPs were characterized by powdered X-ray diffraction (pXRD), FT-IR spectroscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), UV-vis (UV) spectroscopy, and photoluminescence (PL) spectroscopy. Ni–Ag co-incorporation into a ZnO lattice reduces charge recombination by inducing charge trap states between the valence and conduction bands of ZnO and interfacial transfer of electrons. The Ni doped Ag–ZnO solid solution NPs have shown superior 4-nitrophenol reduction compared to pure ZnO NPs which do not show this reaction. Furthermore, a methylene blue (MB) clock reaction was also performed. Antibacterial activity against E. coli and S. aureus has inhibited the growth pattern of both strains depending on the concentration of catalysts.

The synergic effect of Ni and Ag in Ni–Ag–ZnO solid solutions has tuned the optoelectronic properties of ZnO for photoreduction reactions.

Persistent organic pollutants distribution in plasma lipoprotein fractions

This study determines the associations among serum lipid profiles, risk of cardiovascular disease, and persistent organic pollutants. Using Gas chromatography technique, the intensity of toxic pollutant residues in serum samples of Hypertensive patients were measured. Based on statistical analysis, the effects of different covariates namely pesticides, age, systolic blood pressure, diastolic blood pressure, and lipid profile duration was checked using the logistic regression model. Statistical computation was performed on SPSS 22.0. The P-values of F-Statistic for each lipid profile class are greater than 0.01 (1%), therefore we cannot reject the null hypothesis for all cases. The estimated coefficients, their standard errors, Wald Statistic, and odds ratio of the binary logistic regression model for different lipid profile parameters indicate if pesticides increase then the logit value of different lipid profile parameters changes from -0.46 to -0.246 except LDL which increases by 0.135. The study reports a significantly increased threat of cardiovascular disease with increased concentrations of toxic pollutants.

Frequency of risk factors, vaccination status and outcome of tetanus in children at the Children's Hospital Lahore

OBJECTIVE

To determine the frequency of risk factors, vaccination status and outcome of tetanus in children beyond neonatal age at a tertiary care centre.

METHODS

The prospective observational study was conducted at The Children's Hospital, Lahore, Pakistan, from January 2012 to December 2014, and comprised children aged between 1 month and 15 years of either gender admitted with diagnosis of tetanus. Variables recorded included age, gender, vaccination status in terms of number of diphtheria, tetanus and pertussis vaccine doses received per routine infant immunisation and booster doses of tetanus toxoid, risk factors as trauma, ear discharge, ear prick and duration of hospitalisation and outcome. Data was analysed using SPSS 16.

RESULTS

Of the 74 patients, there were 47(63.5%) males and 27(36.5%) females. Overall, the mean age was 6.56+3.15 years 50(67%) were unvaccinated, none (0%) had received booster dose and posttrauma immune prophylaxis. Besides, trauma was the most common risk factor in 33(44.6%) cases followed by ear discharge 15 (20.3%) and ear/nose prick 2(2.7%), while the risk factor was unknown in 24(32.4%) cases. Mean duration of hospitalisation was 14.35±11.65. Mortality rate 16(21.6%) was significantly associated with shorter duration of stay (p<0.001). Mortality was high among unvaccinated children compared to vaccinated children (p=0.01).

CONCLUSIONS

Vaccination coverage was found to be inadequate and post-trauma immune prophylaxis had been ignored..

Spectrum of complications in childhood Enteric Fever as reported in a Tertiary Care Hospital

Objective:

To find out frequency of various complications in children admitted with Enteric Fever at a tertiary care hospital.

Methods:

This was prospective cross sectional study, carried out in the Pediatric Medicine department of The Children’s Hospital Lahore from Dec 2014 to March 2017. Children of both genders with age range of 6 months to 16 years diagnosed as enteric fever on the basis of clinical features and positive Typhidot, or blood culture were included in the study. All 180 patients were scrutinized for all possible complications. Where ever required and feasible appropriate and relevant investigations were done to document complications. Data was analyzed by SPSS version 20.

Results:

Mean age of children was 7.2±3.38, majority 94 (52.2%) were 5-10 years old. Out of 180 patients, complications were noted in 58 (32.2%). Neurological complications 30.7% encompassed maximum complications followed by hepatobiliary 24.61%, abdominal 16.92% hematological 9.23%, bone and joints 7.69%, respiratory system 6.1% and cardiovascular system 4.41%. Mortality rate was 1.6%. Thrombocytopenia and leucopenia were significantly associated with complications with p value of 0.002 and 0.003 respectively.

Conclusion:

Enteric fever is causing our children to suffer by its numerous perplexing and fatal complications. The most vulnerable age for enteric fever and its complication is 5-10 years. To combat these issues large scale vaccination remains promising option at least in most susceptible age group.

A Rare Case of Kikuchi-Fujimoto Disease Associated with Systemic Lupus Erythematosus

Kikuchi-Fujimoto Disease (KFD), also known as histiocytic necrotizing lymphadenitis, is a self-remitting, immune-mediated rare disorder having unique histopathological characteristics which is commonly seen in young Asian females, but can occur in all ethnicities. There is a strong association between KFD and Systemic Lupus Erythematosus (SLE). We present a case of a young Pakistani boy who presented with cervical lymphadenopathy, fever, blackish discoloration of finger tips, and Raynaud's phenomenon. His lymph node biopsy was suggestive of KFD. The American Rheumatology Association diagnostic criteria were not met as no other features of SLE were present. His autoimmune workup including Anti-Nuclear Antibodies (ANA) and Anti-Double Stranded DNA (Anti-Ds DNA) antibodies were positive and supported the diagnosis of SLE. He improved clinically with steroid therapy and nifedipine with resolution of symptoms.

Adherence to asthma treatment and their association with asthma control in children

OBJECTIVE

To assess the degree of medication adherence among asthma patients and association of asthma control level with the degree of adherence.

METHODS

This descriptive cross-sectional study was conducted at The Children's Hospital and The Institute of Child Health, Lahore, Pakistan, from January to December 2015, and comprised persistent asthma patients. Medication adherence in these paediatric subjects was assessed by using Morisky medication adherence assessment questionnaire. Children were categorised using Global Initiative for Asthma guidelines as having well-controlled, partially-controlled or uncontrolled asthma. Data was analysed using SPSS 16.

RESULTS

Out of 310 subjects, 202(65%) were male and 108(34.83%) were female. The overall mean age was 8.9±3.5 years. Of the total, 66(21.3%) had well-controlled asthma, 71(22.9%) partially-controlled and 173(55.8%) uncontrolled. Low adherence was found in 138(44.5%) subjects, medium adherence in 71(22.9%), and high adherence in 101(32.6%). High adherence was significantly associated with well-controlled asthma (p<0.05).

CONCLUSIONS

Adherence with medication regimen was found to be necessary for obtaining maximum therapeutic benefits in children with asthma.

Analyzing communication skills of Pediatric Postgraduate Residents in Clinical Encounter by using video recordings

Objective

To analyze communication skills of pediatric postgraduate residents in clinical encounter by using video recordings.

Methods

This qualitative exploratory research was conducted through video recording at The Children's Hospital Lahore, Pakistan. Residents who had attended the mandatory communication skills workshop offered by CPSP were included. The video recording of clinical encounter was done by a trained audiovisual person while the resident was interacting with the patient in the clinical encounter. Data was analyzed by thematic analysis.

Results

Initially on open coding 36 codes emerged and then through axial and selective coding these were condensed to 17 subthemes. Out of these four main themes emerged: (1) Courteous and polite attitude, (2) Marginal nonverbal communication skills, (3) Power game/Ignoring child participation and (4) Patient as medical object/Instrumental behaviour. All residents treated the patient as a medical object to reach a right diagnosis and ignored them as a human being. There was dominant role of doctors and marginal nonverbal communication skills were displayed by the residents in the form of lack of social touch, and appropriate eye contact due to documenting notes. A brief non-medical interaction for rapport building at the beginning of interaction was missing and there was lack of child involvement.

Conclusion

Paediatric postgraduate residents were polite while communicating with parents and child but lacking in good nonverbal communication skills. Communication pattern in our study was mostly one-way showing doctor's instrumental behaviour and ignoring the child participation.

Patient safety awareness among postgraduate students and nurses in a tertiary health care facility

Objective:

To determine the knowledge of patient safety among postgraduate residents (PGR) and nurses in a tertiary care hospital.

Methods:

This casual comparative study was conducted among the postgraduate residents and nurses working at The Children’s Hospital Lahore in the month of July, August 2017. Both PGR and nurses were asked to complete APSQ-IV questionnaire about patient safety on 7 point Likert scale. Data was analyzed using SPSS version 20 and t-test was used to compare the mean score between two groups. The names of the participants were kept confidential.

Results:

A total of 150 residents and 150 nurses were included. The scores of both postgraduate residents and nurses were similar in all domains having positively worded questions with insignificant difference in mean score (p=0.141). In the reverse coded questions the nurses showed positive perception with higher mean score as compared to postgraduate residents (p=0.004). The postgraduate residents in the early years of residency had higher mean score in positively worded question as compared to residents who were in last years of training (p=0.006). There was no difference in the mean score of nurses as regard to their years of experience (p=0.733). Medical error disclosure domain was reported lowest by both postgraduate residents and nurses.

Conclusion:

Both postgraduate residents and nurses showed positive attitude with good knowledge and perception towards patient safety. Lowest rated scores were from error disclosure confidence domain.

Acute bacterial meningitis in children presenting to The Children's Hospital Lahore before and after pneumococcal vaccine in Pakistan National Immunization Program; A comparison

OBJECTIVE

To describe bacteriological profile, morbidity and mortality of acute bacterial meningitis (ABM) in children and to compare these parameters before and after the introduction of Pneumococcal vaccine in Pakistan National Immunization Program.

METHODS

The present descriptive study was conducted at the Department of Paediatric Medicine of The Children's Hospital Lahore from January 2012 to December 2015. A total of 503 children one month to five years of age admitted with diagnosis of meningitis were included. Complete blood count, CSF cytology, biochemistry, culture sensitivity and blood culture sensitivity were performed.

RESULTS

Frequency of meningitis decreased by 50% in 2013-2015 (199 [2012] vs 304 [2013-2015). Most children in both groups were under one year of age. More neurological complications were seen in the group 2, 20% vs 17%. CSF culture positivity decreased from 12% to 6.6%. Streptococcus pneumoniae isolation decreased from 5 (2.5%) in 2012 to 4 (1.3%) in 2013-2015. Refusal to take feed (p=0.002), impaired sensorium (p=<0.001), severe malnutrition (p=0.001), prolonged duration of symptoms (p=<0.001) and incomplete vaccination status (0.005) were associated with mortality. Mortality rate decreased from 20 (10%) in 2012 to 17 (5.6%) in 2013-2015 but more children developed neurological sequelae 2.7% versus 1%.

CONCLUSION

Acute bacterial meningitis mostly affected children <1 year. Frequency of Streptococcus pneumoniae and mortality of meningitis decreased significantly after PCV but more neurological complications developed in those children who were unvaccinated in 2013-2015 compared to 2012.

Correlation between maternal and childhood VitB12, folic acid and ferritin levels

OBJECTIVE

To determine the correlation between serum folic acid, vitamin B12 and ferritin of mother and child and to study various neonatal risk factors as a cause of anemia in children.

METHODS

One hundred eighty children two months to two years of age admitted in the department of Pediatric Medicine of The Children's Hospital and The Institute of Child Health Lahore from January 2013 to January 2015 with common medical conditions having anemia were included. Complete blood count (CBC), serum ferritin level, folic acid and Vitamin (Vit) B12 level were sent of children and their mothers. Data was analyzed using SPSS version 20.

RESULTS

Out of 180 children with anemia, 66.7% were males. Mean age of children was 7.3months. Fifty-five percent children were malnourished according to z scoring. The mean Hemoglobin (Hb) of children was 8 g/dl. Only 4% children had low ferritin level while 60% had low folic acid and 45% had decreased VitB12. There was significant correlation between Hb of mother and child (p =0.02), Vit B12 deficiency (p=0.008) and iron deficiency (p<0.001). Premature children had lower folic acid levels (p =0.02), while prematurity, IUGR, previous admission and history of sepsis showed no association with anemia in our study. Both breast-feeding and top feeding showed significant association with anemia with p-value of 0.042 and 0.003 respectively while dilution showed no impact on anemia.

CONCLUSION

Maternal anemia has a significant impact on child's hemoglobin. As compared to previous concept of increased iron deficiency in children we found increased occurrence of folic acid and VitB12 deficiency in children and their mothers.

Sequence analysis and structure prediction of enoyl-CoA hydratase from Avicennia marina: implication of various amino acid residues on substrate-enzyme interactions

Enoyl-CoA hydratase catalyzes the hydration of 2-trans-enoyl-CoA into 3-hydroxyacyl-CoA. The present study focuses on the correlation between the functional and structural aspects of enoyl-CoA hydratase from Avicennia marina. We have used bioinformatics tools to construct and analyze 3D homology models of A. marina enoyl-CoA hydratase (AMECH) bound to different substrates and inhibitors and studied the residues involved in the ligand-enzyme interaction. Structural information obtained from the models was compared with those of the reported crystal structures. We observed that the overall folds were similar; however, AMECH showed few distinct structural changes which include structural variation in the mobile loop, formation and loss of certain interactions between the active site residues and substrates. Some changes were also observed within specific regions of the enzyme. Glu106 is almost completely conserved in sequences of the isomerases/hydratases including AMECH while Glu86 which is the other catalytic residue in most of the isomerases/hydratases is replaced by Gly and shows no interaction with the substrate. Asp114 is located within 4Å distance of the catalytic water which makes it a probable candidate for the second catalytic residue in AMECH. Another prominent feature of AMECH is the presence of structurally distinct mobile loop having a completely different coordination with the hydrophobic binding pocket of acyl portion of the substrate.

Predicting the functionally distinct residues in the heme, cation, and substrate-binding sites of peroxidase from stress-tolerant mangrove specie, Avicennia marina

Recent work was conducted to predict the structure of functionally distinct regions of Avicennia marina peroxidase (AP) by using the structural coordinates of barley grains peroxidase as the template. This enzyme is utilized by all living organisms in many biosynthetic or degradable processes and in defense against oxidative stress. The homology model showed some distinct structural changes in the heme, calcium, and substrate-binding regions. Val53 was found to be an important coordinating residue between distal calcium ion and the distal heme site while Ser176 is coordinated to the proximal histidine through Ala174 and Leu172. Different ionic and hydrogen-bonded interactions were also observed in AP. Analyses of various substrate-enzyme interactions revealed that the substrate-binding pocket is provided by the residues, His41, Phe70, Gly71, Asp138, His139, and Lys176; the later three residues are not conserved in the peroxidase family. We have also performed structural comparison of the A. marina peroxidase with that of two class III salt-sensitive species, peanut and soybean. Four loop regions were found to have largest structural deviation. The overall protein sequence was also analyzed for the presence of probable post-translational modification sites and the functional significance of these sites were outlined.

Relationship of awards in multiple choice questions and structured answer questions in the undergraduate years and their effectiveness in evaluation

BACKGROUND

A number of evaluation tools for assessing the cognitive and affective domains in accordance with Bloom's taxonomy are available for summative assessment. At the University of Health Sciences, Lahore, Multiple Choice Questions (MCQs) and Structured Answer Questions (SAQs) are used for the evaluation of the cognitive domain at all six hierarch levels of taxonomy using the tables of specifications to ensure content validity. The rationale of having two evaluation tools seemingly similar in their evaluative competency yet differing in feasibility of construction, administration and marking is being challenged in this study.

METHODS

The MCQ and SAQ awards of the ten percent sample population amounting to 985 students in fifteen Medical and Dental Colleges across Punjab were entered into SPSS-15 and correlated according to the cognitive and affective level of assessment in relation to the Bloom's taxonomy and their grouping in the Tables of Specifications, using parametric tests. 3494 anonymously administered questionnaires were analyzed using ethnograph.

RESULTS

No statistically significant difference was found in the mean marks obtained by the students when MCQs and SAQs were compared according to their groupings in the Tables of Specifications at all levels of cognitive hierarchical testing. End-of-yearcognitive level testing targets set were not met and more questions were set at the lower cognitive testing levels. Expenses incurred in setting MCQs and SAQs were comparable but conduct and assessment costs for MCQs and SAQs were 6% and 94% of the total respectively. In both MCQs and SAQs students performed better at higher cognitive testing levels whereas the SAQs and MCQs were able to marginally test the lower levels of affective domain only. Student's feedback showed that attempting MCQs required critical thinking, experience and practice.

CONCLUSION

MCQs are more cost effective means at levels of cognitive domain assessment.