Effect of phosphate buffer on the complexation and photochemical interaction of riboflavin and caffeine in aqueous solution: A kinetic study

A study of the photodegradation of 5×10−₅ M riboflavin (RF) in 0.2-1.0 M phosphate buffer in the presence and absence of 2.50×10-₄ M caffeine at pH 6.0-8.0 has been carried out. RF in phosphate buffer is photodegraded simultaneously by normal photolysis (photoreduction) and photoaddition reactions giving rise to lumichrome (LC) and cyclodehydroriboflavin (CDRF) as the main final products, respectively. RF and its photoproducts, formylmethylflavin (FMF), lumiflavin (LF), LC and CDRF in degraded solution have been determined by a specific multicomponent spectrophotometric method with an accuracy of ±5

Anatomical Variation of Olfactory Fossa on Computed Tomography of Paranasal Sinuses

Objective: To determine the frequency of anatomical variation of olfactory fossa among the adult Pakistani population by Keros classification on computed tomography (CT) of paranasal sinuses. Study Design: Cross-sectional study Place and Duration of Study: Department of Radiology, Combined Military Hospital, Rawalpindi Pakistan, from May 2019 to Mar 2020. Methodology: A total of 65 patients of either gender were included. Patients with previous trauma or surgery of the skull base or paranasal sinuses, malignant diseases of the sinuses and congenital anomalies were excluded. All the included patients in the study underwent CT paranasal sinuses. Measurements of the olfactory fossae followed by grouping as per Kero’s classification were done, and CT findings were recorded. Results: The patients included in the study ranged from 18 to 65 years, with a mean age of 33.09±10.86 years and 72.3% of patients 18 to 40 years of age. Of 65 patients, 36(55.4%) were males, and 29(44.6%) were females. The mean CT depth of the olfactory fossa was 6.34 ±4.03mm. Type-I olfactory fossa by Keros classification was found in 17(26.2%), Type-II in 35(53.8%) and Type-III in 13(20%) of patients. Conclusion: This study concluded that Keros Type-II is the most common anatomical variation of olfactory fossa among the adult Pakistani population on CT of paranasal sinuses with an intermsediate risk of intracranial complications during endoscopic sinus surgery involving this region

Photodegradation of levofloxacin in aqueous and organic solvents: A kinetic study

The kinetics of photodegradation of levofloxacin in solution on UV irradiation in the pH range 2.0–12.0 has been studied using a HPLC method. Levofloxacin undergoes first-order kinetics in the initial stages of the reaction and the apparent first-order rate constants are of the order of 0.167 to 1.807×10–3 min–1. The rate-pH profile is represented by a curve indicating the presence of cationic, dipolar and anionic species during the reaction. The singly ionized form of the molecule is non-fluorescent and is less susceptible to photodegradation. The increase in the degradation rate in the pH range 5.0–9.0 may be due to greater reactivity of the ionized species existing in that range. The rate appears to vary with a change in the degree of ionization of the species present in a particular pH range and their susceptibility to photodegradation. Above pH 9, the decrease in the rate of photodegradation may be result of deprotonation of the piperazinyl group. The levofloxacin molecule is more stable in the pH range around 7, which is then suitable for formulation purposes. The photodegradation of levofloxacin was found to be affected by the dielectric constant and viscosity of the medium

Techno commercial analysis of liquefied petroleum gas recovery from natural gas using Aspen HYSYS

Liquefied petroleum gas is an alternative, relatively clean and a supreme source of energy, which is being used as a key component in the global energy supply. The international trade agreements and the chemical and non-chemical demand of liquefied petroleum gas with the increase in the world’s population have brought its production from the processing of natural gas to the limelight. During its processing, a variety of different components are extracted from it, including methane and ethane which remains in the bulk as natural gas. The objective of this research work is to find the capability of investigating the liquefied petroleum gas recovery performance to make the process economical by saving the processing cost and energy. The novelty of this work is to deal with the design and simulation of a liquefied petroleum gas plant using Aspen HYSYS. To make this process energy efficient and economical, different schemes of process alternatives were applied by reducing the sizes of the exchanger and other pieces of equipment. Three cases are studied in which feed is precooled by rerouting the stream and/or by repositioning of the chiller for the recovery of liquefied petroleum gas from natural gas by analyzing their cost and process parameters. The modelling and simulation base case and three different case studies are realized in Aspen HYSYS. It has been observed that case study 2 results in about 10% increase in LPG production where the chiller is repositioned in the separation section of the LPG production flowsheet. Case study 3 shows a maximum decrease in hot side utilities in the flowsheet of about 20% while 10 and 14% decreases are observed for case studies 1 and 2, respectively. Furthermore, economic analysis indicates about 18 and 22% in the capital cost for case studies 2 and 3, respectively, due to the lower size of process units. The outcome of this investigation is to present plenty of suggestions to improve the process efficiency and minimize the requirement to over design the plant components

Impact of 10-valent pneumococcal conjugate vaccine (PCV10) on nasopharyngeal carriage in children 2 years of age: Data from a four-year time series cross-sectional study from Pakistan

The dataset described in this paper was collected for a time-series cross-sectional study exploring the impact of 10-valent Pneumococcal Conjugate Vaccine (PCV10) on nasopharyngeal (NP) carriage in children under 2 years of age from a rural population in Sindh, Pakistan. The study was carried out in two union councils of Matiari - Khyber and Shah Alam Shah Jee Wasi (Latitude 25.680298 / Longitude 68.502711). Data was collected on socio-demographics, clinical characteristics and vaccination status using android phone-based application. NP samples were collected using standard World Health Organisation (WHO) techniques, culture and serotyping was done using sequential Multiplex PCR described by Centre for Disease Control, USA. We looked at the carriage rate of vaccine type (VT) and non-vaccine type (NVT) serotypes over time in vaccinated and unvaccinated children. We additionally looked at the predictors for pneumococcal carriage. The uploaded dataset, available on Mendeley data repository (Nisar, Muhammad Imran (2021), Impact of PCV10 on nasopharyngeal carriage in children in Pakistan , Mendeley Data, V1, doi:10.17632/t79h6g97gr.1), has 3140 observations in CSV format. Additional files uploaded include a data dictionary and the set of questionnaires. The dataset and accompanying files can be used by other interested researchers to replicate our analysis, carry similar analysis under varying set of assumptions or perform additional exploratory or metanalysis

Direct and indirect effect of 10 valent pneumococcal vaccine on nasopharyngeal carriage in children under 2 years of age in Matiari, Pakistan

Background: Pakistan introduced Ten-valent pneumococcal-conjugate-vaccine PCV10 in 2012 as a 3 + 0 schedule without catch-up.Methods: Children \u3c2 years old in Matiari, Sindh provided nasopharyngeal swabs between 2014 and 2018, which were cultured for pneumococcus and serotyped through multiplex PCR at the Aga Khan University Hospital. Carriage rates over time for Vaccine-Type (VT) and Non-VT (NVT) serotypes were used to estimate direct, indirect, total and overall effects of vaccination. Regression analysis was used to determine factors associated with VT carriage.Results: Pneumococcus was detected in 2370/3140 (75%). VT carriage decreased overall, 16.1-9.6% (p-trend \u3c0.001); vaccinated (all 3 doses of PCV10 received) 11.3-8.1% (p-trend 0.031) and unvaccinated (no PCV10 dose received) 17.4-10.3% (p-trend 0.003) with a decline in serotypes 6B, 9V/9A and 19F. Immunization increased from 41.0% to 68.4% (p-trend 0.001). Direct effect of vaccine was 32.8% (95% CI 14.7-47.0%) and indirect effect 44.6%(95% CI 40.6-48.6%). Factors associated with decreased VT colonization were education 1-5 years (aOR 0.7, 95%CI 0.6-1.0), history of difficulty breathing (aOR 0.7, 95%CI 0.5-1.0), exposure to smoke (aOR 0.8, 95% CI 0.6-1.0), child fully immunized (aOR 0.7, 95%CI 0.5-1.0) and enrolled in 3rd (aOR 0.6, 95%CI 0.4-0.8) and 4th (aOR 0.6, 95%CI 0.5-0.9) year of the study whereas history of runny nose (aOR 1.5, 95% CI 1.2-1.9) was positively associated.Conclusions: Decrease in VT pneumococcal carriage in vaccinated and unvaccinated children indicates herd immunity. Sustained increase in vaccine coverage and close long-term surveillance is warranted

A novel missense mutation in TNNI3K causes recessively inherited cardiac conduction disease in a consanguineous Pakistani family

Cardiac conduction disease (CCD), which causes altered electrical impulse propagation in the heart, is a life-threatening condition with high morbidity and mortality. It exhibits genetic and clinical heterogeneity with diverse pathomechanisms, but in most cases, it disrupts the synchronous activity of impulse-generating nodes and impulse-conduction underlying the normal heartbeat. In this study, we investigated a consanguineous Pakistani family comprised of four patients with CCD. We applied whole exome sequencing (WES) and co-segregation analysis, which identified a novel homozygous missense mutation (c.1531T\u3eC;(p.Ser511Pro)) in the highly conserved kinase domain of the cardiac troponin I-interacting kinase (TNNI3K) encoding gene. The behaviors of mutant and native TNNI3K were compared by performing all-atom long-term molecular dynamics simulations, which revealed changes at the protein surface and in the hydrogen bond network. Furthermore, intra and intermolecular interaction analyses revealed that p.Ser511Pro causes structural variation in the ATP-binding pocket and the homodimer interface. These findings suggest p.Ser511Pro to be a pathogenic variant. Our study provides insights into how the variant perturbs the TNNI3K structure-function relationship, leading to a disease state. This is the first report of a recessive mutation in TNNI3K and the first mutation in this gene identified in the Pakistani population