Saccharomyces Cerevisiae as a Model Organism for Retrospective Impedance Biodosimetry.

ABSTRACT: Previous studies have shown that measuring changes in electrical impedance that follow radiation-induced suppression of metabolic activity in irradiated yeast cells can be used to determine radiation dose. The current work investigates the radiation response of Saccharomyces cerevisiae cells by using metabolic activity of cells as a damage indicator. Impedance biodosimetry was examined as a method to evaluate the radiation response of yeast cells. Active lab-grade dry yeast cells were used as the biological material as these samples are simple to handle and have a long shelf-life. A novel dosimeter design has been developed with a strict fabrication method and measurement procedure to ensure reproducible measurements are possible. Prepared yeast samples were irradiated to doses from 0.5 to 8 Gy using a 137Cs source, and a dose response curve was developed that showed a linear relationship of dose with changes in impedance measurements. Fading of the impedance signal was also investigated, and it was shown that there was no noticeable fading of the impedance signal over a period of 7 mo. Finally, the lowest detectable limit measured using this methodology was determined to be 300 mGy. This work presents an alternative retrospective dosimetry technique that can be used at a high scale and low cost following large-scale radiological accidents.

Gastric organoaxial volvulus: A lethal twist and a rare cause of acute abdomen.

Organoaxial gastric volvulus is a rare clinical condition. We present a 55 years old man with an acute episode of melena and hematemesis with moderate epigastric pain which was unresponsive to analgesics. Initially, the patient was misdiagnosed and treated symptomatically for other gastrointestinal conditions but later contrast-enhanced abdominal CT scan revealed gastric organo-axial volvulus, which was associated with a right hiatal hernia. The patient underwent surgical treatment, including crural dissection, posterior esophageal window creation, lower esophageal sling, crural defect repair with porcine meshes, and anterior gastropexy, followed by intensive physiotherapy and antibiotics. Diagnosis of gastric volvulus can be challenging, due to its symptom similarity to other gastrointestinal disorders, necessitating a high level of suspicion.

Electron paramagnetic resonance spectroscopy for the detection of radiation exposure in dreissenid mussels.

Electron paramagnetic resonance (EPR) spectroscopy, established for radiation measurements in calcified tissues, was identified as a methodology that merits investigation for the purpose of environmental radiation measurements using dreissenid mussels from the Great Lakes. With the refinement of sample preparation and measurement protocols, a linear relationship of dose with the peak-to-peak height of the radiation-induced signal at g = 2.0034 was established. A dedicated analysis algorithm was developed to process batches of samples, eliminating the need for manual peak-to-peak height measurement. Varying background EPR signals were identified in different sampling groups, with samples gathered in winter having a markedly lower background signal. Through optimisation of spectrum acquisition normalisation methods, it was possible to resolve doses as low as 0.2 Gy. This work provides further validation that EPR dosimetry of shelled species has the potential to contribute to better characterisation of absorbed doses in aquatic environments.

A rare case of recurrent hydatid cyst of the spleen: A case report.

Cystic echinococcosis (CE), or hydatid disease, is a parasitic infection caused by Echinococcus granulosus endemic to areas with considerable pastoral farming and animal husbandry. Typical presentations include hydatid cyst formation in the liver, lungs, brain, kidneys, or bones. An isolated splenic hydatid cyst is an extremely rare occurrence, accounting for only 0.5%-4% worldwide incidence rates, and recurrent cases are even more infrequent. Globalization, cross-border travel, and altered immigration patterns over time have shifted some of the burden of CE from the developing to the developed world, making the diagnosis challenging for these nonendemic areas. Judicious use of imaging modalities for prompt diagnosis and effective intervention is necessary to treat the initial disease and prevent a recurrence. Herein, we present the case of a 13-year-old male with recurrent isolated splenic hydatid cyst. The patient presented with chronic and nonradiating pain in his left hypochondrium. Physical examination revealed splenomegaly. Ultrasonography showed multiple cysts. Computerized tomography (CT) scan showed cystic lesions in splenic parenchyma with numerous internal enhancing septae. Surgical evacuation was performed for the management of disease.

Molecular and Genetic Characterization of Hepatitis B Virus (HBV) among Saudi Chronically HBV-Infected Individuals.

The study aimed to characterize the genotype and subgenotypes of HBV circulating in Saudi Arabia, the presence of clinically relevant mutations possibly associated with resistance to antivirals or immune escape phenomena, and the possible impact of mutations in the structural characteristics of HBV polymerase. Plasma samples from 12 Saudi Arabian HBV-infected patients were analyzed using an in-house PCR method and direct sequencing. Saudi patients were infected with mainly subgenotype D1. A number of mutations in the RT gene (correlated to antiviral resistance) and within and outside the major hydrophilic region of the S gene (claimed to influence immunogenicity and be related to immune escape) were observed in almost all patients. Furthermore, the presence of mutations in the S region caused a change in the tertiary structure of the protein compared with the consensus region. Clinical manifestations of HBV infection may change dramatically as a result of viral and host factors: the study of mutations and protein-associated cofactors might define possible aspects relevant for the natural and therapeutic history of HBV infection.

Efficacy and Safety of Favipiravir in Treating COVID-19 Patients: A Meta-Analysis of Randomized Control Trials.

This meta-analysis was conducted with the aim to assess the safety and efficacy of favipiravir in treating patients with coronavirus disease 2019 (COVID-19). It was carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We performed a thorough search of online databases including PubMed, EMBASE, and the Cochrane Library from their inceptions to November 30, 2022, using the following search terms: "Favipiravir" AND "COVID-19". We included randomized control trials (RCTs) that were conducted to determine the efficacy and safety of favipiravir for COVID-19. Efficacy outcomes assessed in this meta-analysis included time to viral clearance in days, time to clinical improvement in days, need for supplementary oxygen, and requirement of ICU admission. For safety outcomes, we compared overall adverse events and serious adverse events that had occurred during the treatment between the patients in the treatment group and the control group. Eight studies involving 1,448 patients were included in this meta-analysis. The results showed that no significant differences were found between the two groups in terms of time to viral clearance, time to clinical improvement, and the need for supplementary oxygen and ICU admission. In terms of safety, no significant differences were found between the two groups in relation to adverse events and serious adverse events. The current study found that favipiravir did not exert any beneficial impact on reducing ICU admission, the need for oxygen therapy, and time to viral clearance. However, a slight benefit was reported with regard to the time for clinical improvement, but it was insignificant between the two study groups.

A Practical Method for EPR Dosimetry Using Alanine Powder.

ABSTRACT: This work investigates alanine powder, an inexpensive and versatile material compared to alanine pellets, as a standardized dosimeter for the alanine-EPR system using a Bruker EMX-Micro spectrometer. The feasibility of this method was investigated, and a calibration curve was produced using 40 dosimeters, which were prepared by tightly packing DL-alanine powder in polypropylene microcentrifuge tubes. The dosimeters were irradiated to doses ranging from 0.2-20 Gy using a 60 Co source. A dosimeter handling and measurement protocol was established for all dosimeters. The dosimetric signal was evaluated by measuring the peak-to-peak height of the central resonance peak, and the dose response of alanine powder dosimeters showed a linear behavior in the investigated dose range with relative errors below 13%. Measurement repeatability and reproducibility were tested to show the errors associated with sample placement in the cavity and with the overall measurement method, with both tests showing relative errors below 7%. As an inexpensive material compared to pellet dosimeters, alanine powder has a strong potential to be used as a standardized material for radiation dosimetry applications. The scope of this work is to present an effective and comprehensive methodology with accompanying analysis scripts for dosimetry with alanine powder that is useful in a wide range of applications and dose requirements.

Quality of Life of Post-renal Transplant Patients in Rawalpindi.

Objectives The objective is to assess the overall quality of life (QoL) in patients who had undergone renal transplant within the last three years and correlate this index with various demographic variables such as age, gender, marital status, and education level and to correlate the QoL score calculated vs. the health status perceived by the patients themselves Materials and methods This was an analytical cross-sectional study, carried out over a period of five months. A total of 123 patients were targeted among which data from 79 patients were gathered including all the patients that underwent kidney transplantation in the past three years at a renal transplant center in CMH, Rawalpindi, Pakistan. Non- Probability convenience sampling was used, and data were collected using the WHOQOL-BREF tool that contained 25 questions targeted to four domains (physical, psychological, social, and environmental). The Questionnaire was administered over the phone with proper consent taken beforehand. Data were analyzed using Excel and SPSS version 23. Results A total of 79 patients were administered the questionnaire with the mean age of our study population being 35±11 years out of which 84.5% were male and 15.5% were female. Patients received the kidney from relative donors (98.4%) with the highest percentage being sister donors (30.9%). The majority of patients reported from Punjab (54.4%), with the rest from far-flung rural areas. An estimated 62.5% of the patients presented with other systemic/psychological disorders such as DM+, IHD, HTN, Hepatitis C, depression, etc. The mean global score of these patients was 79.21 which can be broken down into four domains, physical domain 80.40, psychological domain 78.99, social domain 82.70, and environmental domain 74.75. Conclusion In a developing country such as Pakistan, with most of the patients belonging to lower or middle socioeconomic groups, we believe that the patient's own sense of QoL is overshadowed by the mere exuberance of being given a second chance at life which was portrayed by the discrepancies in the perceived vs actual QoL graph. One common recurring theme that was noticed whilst interviewing the patients was that the difficulties they might have faced post-transplant paled in comparison to how grateful they were to live another day. A positive trend was noticed between the time since transplant and the QoL score which could be attributed to various factors such as the use of aggressive immunosuppressants, fear of injury, fear of transplant rejection, etc. in the first-year post-transplant. Demographic variables such as income, age, location, etc. did not affect the scores of these patients on a great scale. The present study aims to guide clinicians in the improvement of long-term outcomes of renal transplantation in Pakistan.

Analysis of the Nd dopant on optical, dielectric and biological properties of ZnO nanostructures.

The effect of neodymium (Nd+3) on ZnO thin films has been studied with varying Nd doping percentage ranging from 1 to 5 wt%. XRD graphs confirmed that Nd ions have incorporated into the ZnO lattice without any structural modification. The increase of crystallite size was observed to vary from 27.5 to 31.90 nm with the increment in Nd amount. The optical spectra exhibited transparency in the visible region. The higher transmission was possessed at 1 wt at% Nd concentration. The band gap of Nd-doped ZnO thin films showed variation with the increase in Nd dopant concentration. The increment in dielectric constant and tangent loss was observed with the increase in Nd doping. The change in DC conductivity with frequency was measured by using Jonscher's power law while AC conductivity was explained with the hopping-barrier mechanism. The effects of Nd concentration on antibacterial efficiency against four different bacterial strains Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa), Klebsiella Pneumonia (K. Pneumonia), and Staphylococcus aureus (S. aureus) were investigated whereas antifungal activity of Nd-ZnO was done against Aspergillus fumigate by using agar disc-diffusion method. ZnO with 4 wt % Nd demonstrated the best photo-catalytic property.