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1.
Cureus ; 16(1): e52347, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38361688

ABSTRACT

Objectives Antinuclear antibodies (ANA) are autoantibodies that are associated with and ordered to diagnose autoimmune connective tissue disease. ANA have high sensitivity (~98%) but low specificity (~75%), and because they can be found in healthy individuals and non-rheumatologic conditions leading to their elevation, ANA tests are often requested and interpreted inappropriately by clinicians. The aim of this study was to retrospectively assess how frequently ANA testing is repeated in the adult population of Saudi Arabia (SA) and which factors are associated with and lead to inappropriate testing. Methodology We investigated a study group of 40,634 adult patients who underwent 229,825 ANA tests from 2018 to 2022 in an academic hospital in Jeddah, SA. We took a random sample of 500 patients from the study group, along with their 998 ANA tests, to look in depth into our research questions. Variables related to patients, ANA tests, and ordering physicians were collected. Descriptive and analytical statistics were employed to address the research questions, and a p-value < 0.05 was considered statistically significant. Results We found 57% of the ordered ANA tests to have positive results, with the most common titers of mild positivity being 1:80 and 1:160. Most repeated ANA tests were ordered with an interval of more than one year, and when repeated, 67% of test results remained unchanged. The majority of seroconversions resulted from negative ANA tests or those with weak (titer 1:40) or mild positivity (titer 1:80-1:160). The results of the moderate (titer 1:320-1:640) and strong (titer ≥1280) positivity ANA tests did not change. Only 11% of repeated ANA tests were found to be appropriate for repetition. The most common specialties associated with ordering ANA tests in general were internal medicine, followed by rheumatology, and finally family medicine. Our correlation analysis revealed that being female, having systemic connective tissue disease, and having a rheumatologist as a specialist were all associated with ordering more than 10 ANA tests (p < 0.05). Conclusion Because the results of repeated ANA tests did not change much, our study suggests that the cost of repeating ANA tests and the subsequent potentially unnecessary interventions should all be carefully examined before scheduling a repeated ANA test. Further studies involving patients from SA and across wider healthcare settings (academic, community, and private hospitals and healthcare centers) are warranted.

2.
ACS Omega ; 8(40): 36775-36788, 2023 Oct 10.
Article in English | MEDLINE | ID: mdl-37841128

ABSTRACT

In order to elucidate the effect of shear and cooling process on structural, thermomechanical, and physical properties of polymer melt, excess entropy, a thermodynamic quantity is calculated from radial distribution function generated from equilibrated parts of the molecular simulation trajectories. The structural properties are calculated, which includes the density of polypropylene melt, end to end distance, radius of gyration of the polypropylene polymer chain, and monomer-monomer radial distribution function. Non-equilibrium molecular dynamics simulation was employed to investigate the role of the applied shear rate on the properties of polypropylene. Furthermore, a range of cooling rates were employed to cool the melt. Thermomechanical properties, such as Young's modulus, and physical properties, such as glass transition temperature, were determined for different cases. Results showed that slow cooling and high shear substantially improved the Young's modulus and glass transition temperature of the i-PP. Furthermore, a two-body contribution to the excess entropy was used to elucidate the structure-property relationships in the polymer melt as well as the glassy state and the dependence of shear and cooling rate on these properties. We have used the Rosenfeld excess entropy-viscosity relationship to calculate the viscous behavior of the polymer under a steady shear condition.

3.
Molecules ; 28(6)2023 Mar 08.
Article in English | MEDLINE | ID: mdl-36985439

ABSTRACT

Shigellosis is a serious foodborne diarrheal disease caused by the Shigella species. It is a critical global health issue. In developing countries, shigellosis causes most of the mortality in children below 5 years of age. Globally, around 165 million cases of diarrhea caused by Shigella are reported, which accounts for almost 1 million deaths, in which the majority are recorded in Third World nations. In this study, silver nanoparticles were synthesized using Mangifera indica kernel (MK-AgNPs) seed extracts. The biosynthesized M. indica silver nanoparticles (MK-AgNPs) were characterized using an array of spectroscopic and microscopic tools, such as UV-Vis, scanning electron microscopy, particle size analyzer, Fourier transform infrared spectroscopy, and X-ray diffractometer. The nanoparticles were spherical in shape and the average size was found to be 42.7 nm. The MK-AgNPs exhibited remarkable antibacterial activity against antibiotic-resistant clinical Shigella sp. The minimum inhibitory concentration (MIC) value of the MK-AgNPs was found to be 20 µg/mL against the multi-drug-resistant strain Shigella flexneri. The results clearly demonstrate that MK-AgNPs prepared using M. indica kernel seed extract exhibited significant bactericidal action against pathogenic Shigella species. The biosynthesized nanoparticles from mango kernel could possibly prove therapeutically useful and effective in combating the threat of shigellosis after careful investigation of its toxicity and in vivo efficacy.


Subject(s)
Dysentery, Bacillary , Mangifera , Metal Nanoparticles , Shigella , Child , Humans , Mangifera/chemistry , Metal Nanoparticles/chemistry , Silver/pharmacology , Silver/chemistry , Dysentery, Bacillary/drug therapy , Plant Extracts/pharmacology , Plant Extracts/chemistry , Microbial Sensitivity Tests , Spectroscopy, Fourier Transform Infrared , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Seeds
4.
Neurosciences (Riyadh) ; 28(1): 27-35, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36617460

ABSTRACT

OBJECTIVES: To determine the prevalence of Obsessive-Compulsive Disorder (OCD) symptoms in patients who have survived COVID-19. METHODS: The study used an observational cross-sectional design between July and October 2021. The target population was adult patients who had confirmed COVID-19 infection prior to joining the study, OCD symptoms were assessed using the Arabic OCD scale created by Abohendy and colleagues, which included 83 questions covering 12 different domains and was administired online. RESULTS: A total of 356 patients were included in the analysis. Approximately 9.0% and 1.7% of the patients had a history of psychiatric disease and OCD diagnosis (respectively). The total symptom score was 32.8%. The most frequently reported domains were rumination of ideas (55.5%), re-checking compulsions (37.0%), and slowness (34.0%), while the least frequently reported domains included obsessive impulses (26.3%), obsessive images (26.5%), and religious compulsions (26.8%). Unlike other domains, the purity and cleanliness compulsions scores were significantly higher than the scale reference population. A higher total symptom score was observed in psychiatric patients (p=0.004) and, to a lesser extent, in OCD patients (p=0.250). CONCLUSION: Overall, OCD symptoms, including cleanliness and fear of disease obsessions, tend to be higher in psychiatric and OCD patients, these findings are valuable for future studies.


Subject(s)
COVID-19 , Obsessive-Compulsive Disorder , Adult , Humans , Prevalence , Saudi Arabia/epidemiology , Cross-Sectional Studies , COVID-19/epidemiology , Obsessive-Compulsive Disorder/epidemiology , Obsessive-Compulsive Disorder/diagnosis , Obsessive-Compulsive Disorder/psychology , Psychiatric Status Rating Scales
5.
Int J Biol Macromol ; 230: 123254, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36641020

ABSTRACT

The synthetic food additive dye induces amyloid fibrillation has many implications in the laboratory and industries. The effect of Allura red (AR), on the fibrillation of ovalbumin (Ova) at pH 2.0 was investigated. The influence of salt and pH was also seen on AR-induced Ova aggregation. We have used several spectroscopic and microscopy techniques to characterize the changes. The turbidity data suggest that concentrations above 0.05 mM of AR induce aggregation, and the size of aggregates increased in response to AR concentration. The kinetics data showed that the AR induces Ova aggregation quickly without lag time. The aggregates induced by AR have amyloid-like aggregates confirmed by far-UV CD and TEM. NaCl has very marginal effects in AR-induced aggregation. The turbidity results clearly state that Ova is not forming aggregates with pH above 4.0 due to electrostatic repulsion. However, Ova forms bigger aggregates in the presence of 0.5 mM AR at a pH below 4.0. These spectroscopic data suggest that the amyloid fibrillation that occurs in Ova is due to electrostatic and hydrophobic interaction. The amyloid fibrillation induced by AR dye in protein should be taken seriously for food safety purposes.


Subject(s)
Azo Compounds , Food Additives , Ovalbumin , Azo Compounds/pharmacology , Azo Compounds/chemistry , Sodium Chloride , Amyloid/chemistry , Amyloidogenic Proteins , Hydrogen-Ion Concentration , Protein Aggregates
6.
Microbiol Res ; 266: 127246, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36327661

ABSTRACT

The emergence of antibiotic resistance among animal farms impels the development of novel antimicrobials or strategies for agri-food production. The combinational use of agents to achieve a synergistic antimicrobial effect provides many advantages such as dosage reduction, shortened treatment time, and avoidance of antimicrobial resistance. In this study, we evaluated the killing efficacy of single agent or combinational use of three antimicrobials, including cinnamon oil, encapsulated curcumin and zinc oxide nanoparticles (ZnO NPs), against a leading foodborne pathogen Campylobacter jejuni. We then investigated the antimicrobial mechanism using whole transcriptome sequencing analysis (RNA-Seq). The single-agent treatment of cinnamon oil, encapsulated curcumin, or ZnO NPs showed a significant antimicrobial effect against C. jejuni by generating more than 8-log reduction within 3 h. The transcriptional signatures of C. jejuni in response to these agents varied, indicating that these agents shared distinct mechanisms of action and were likely to generate synergistic effects. Cinnamon oil affected the integrity of cell membrane, which might lead to an increase in cell permeability. Encapsulated curcumin and ZnO NPs disrupted bacterial outer membranes and cell membranes against the same membrane protein targets. The combinational use of these agents showed synergistic antimicrobial effects and distinct mechanisms of action compared to single treatment. The combination of cinnamon oil and encapsulated curcumin provoked the expression of cellular signaling, but repressed the chemotaxis-associated genes. The antimicrobial resistance associated genes showed a low expression level in the combination of encapsulated curcumin and ZnO NPs. The tri-combination treatment systematically overexpressed genes involved in the amino acid synthesis, protein translation, and membrane protein synthesis. This study provides new insights in combating Campylobacter with minimizing the development of antimicrobial resistance in long-term usage.


Subject(s)
Campylobacter jejuni , Curcumin , Nanoparticles , Zinc Oxide , Animals , Campylobacter jejuni/genetics , Zinc Oxide/pharmacology , Zinc Oxide/chemistry , Curcumin/pharmacology , Exome Sequencing , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Membrane Proteins , Microbial Sensitivity Tests
7.
Int J Biol Macromol ; 219: 1351-1359, 2022 Oct 31.
Article in English | MEDLINE | ID: mdl-36058397

ABSTRACT

Several food dyes are known to induce amyloid fibrillation when interacting with proteins. Here, we studied the role of sunset yellow (SY) in the amyloid fibrillation of hen egg white lysozyme (HEWL) and characterized the changes using spectroscopy techniques. Turbidity results showed that SY dye induces aggregation in HEWL in concentrations dependent manner. The aggregation induced by SY dye is kinetically very fast, no lag phase was detected, and the kinetics process follows an isodesmic kinetics pathway. The SY-dye induce aggregates have cross-ß secondary structure confirmed by far-UV CD measurements. The effect of salts and solvents was also seen on SY-induced aggregates. Turbidity, far-UV CD, and kinetics results suggest that certain concentrations of NaCl and (NH4)2SO4 solubilize the SY-induce amyloid fibrils, but (NH4)2SO4 is more effective. Similarly, solvents are also solubilized the SY-induces HEWL amyloid fibrillation but the order of defibrillation is as follows: Isopropanol> ethanol > methanol which signified that isopropanol is more effective than other solvents. The salts and solvents data suggest that the electrostatic, as well as hydrophobic interaction, is responsible for SY-induced amyloid fibrillation. These conformational changes should be examined, more seriously for the purpose of food safety.


Subject(s)
Amyloid , Food Coloring Agents/toxicity , Muramidase , 2-Propanol , Amyloid/chemistry , Animals , Azo Compounds , Chickens/metabolism , Coloring Agents , Egg White/chemistry , Ethanol , Methanol , Muramidase/chemistry , Salts/chemistry , Salts/pharmacology , Sodium Chloride , Solvents
8.
Molecules ; 27(8)2022 Apr 12.
Article in English | MEDLINE | ID: mdl-35458685

ABSTRACT

The increase in ß-lactam-resistant Gram-negative bacteria is a severe recurrent problem in the food industry for both producers and consumers. The development of nanotechnology and nanomaterial applications has transformed many features in food science. The antibacterial activity of zinc oxide nanoparticles (ZnO NPs) and their mechanism of action on ß-lactam-resistant Gram-negative food pathogens, such as Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, Serratia marcescens, Klebsiella pneumoniae, and Proteus mirabilis, are investigated in the present paper. The study results demonstrate that ZnO NPs possesses broad-spectrum action against these ß-lactamase-producing strains. The minimal inhibitory and minimal bactericidal concentrations vary from 0.04 to 0.08 and 0.12 to 0.24 mg/mL, respectively. The ZnO NPs elevate the level of reactive oxygen species (ROS) and malondialdehyde in the bacterial cells as membrane lipid peroxidation. It has been confirmed from the transmission electron microscopy image of the treated bacterial cells that ZnO NPs diminish the permeable membrane, denature the intracellular proteins, cause DNA damage, and cause membrane leakage. Based on these findings, the action of ZnO NPs has been attributed to the fact that broad-spectrum antibacterial action against ß-lactam-resistant Gram-negative food pathogens is mediated by Zn2+ ion-induced oxidative stress, actions via lipid peroxidation and membrane damage, subsequently resulting in depletion, leading to ß-lactamase enzyme inhibition, intracellular protein inactivation, DNA damage, and eventually cell death. Based on the findings of the present study, ZnO NPs can be recommended as potent broad-spectrum antibacterial agents against ß-lactam-resistant Gram-negative pathogenic strains.


Subject(s)
Metal Nanoparticles , Nanoparticles , Zinc Oxide , Anti-Bacterial Agents/metabolism , Anti-Bacterial Agents/pharmacology , Bacteria , Escherichia coli , Microbial Sensitivity Tests , Zinc Oxide/metabolism , Zinc Oxide/pharmacology , beta-Lactamases/metabolism , beta-Lactams/metabolism
9.
Foods ; 11(3)2022 Feb 03.
Article in English | MEDLINE | ID: mdl-35159610

ABSTRACT

The functionality of hydrocolloids of different origins, gum Cordia (GC), and gum ziziphus (GZ) on pan bread and sponge cake quality and their potential use in retarding the staling process have been studied. The effects of the gums were determined by assessing the pasting qualities of wheat flour slurry, dough properties, and the finished product. After 24 and 96 h of storage, investigations were conducted on the finished product. Micro-doughLab was used to assess dough mixing qualities, and a texture profile analysis (TPA) test was used to assess the texture. A hedonic sensory test of texture, scent, taste, color, and general approval was also conducted. The type of gum used had a significant impact on the physical properties of the bread and cake and their evolution through time. Reduced amylose retrogradation was demonstrated by the lower peak viscosity and substantially lower setback of wheat flour gels, which corresponded to lower gel hardness. Gums were superior at increasing the bread loaf volume, especially GZ, although gums had the opposite effect on cake volume. After both storage periods, the hardness of the bread and cake was much lower than that of the control. Except when 2% GC was used, adding GC and GZ gums to bread and cake invariably increased the overall acceptability of the product. In terms of shelf-life, GZ was able to retain all texture parameters, volume, and general acceptability close to the control after storage.

10.
Polymers (Basel) ; 14(3)2022 Jan 20.
Article in English | MEDLINE | ID: mdl-35160385

ABSTRACT

Protein aggregation is of two types: (i) amorphous and (ii) amyloid fibril. Several extrinsic factors (temperature, pH, and small ligands) stimulate protein aggregation in vitro. In this study, we have examined the role of sunset yellow (SY) on the ß-lactoglobulin (BLG) aggregation at pH 2.0. We have used spectroscopic (turbidity, Rayleigh light scattering (RLS), far-UV CD) and microscopic (transmission electron microscopy [TEM]) techniques to describe the effects of SY on BLG aggregation. Our results showed that BLG aggregation is dependent on SY concentrations. Very low concentrations (0.0-0.07 mM) of SY were unable to induce aggregation, while SY in the concentrations range of 0.1-5.0 mM induces aggregation in BLG. The kinetics of SY-stimulated aggregation is very fast and monomeric form of BLG directly converted into polymeric aggregates. The kinetics results also showed SY-induced BLG aggregation disappeared in the presence of NaCl. The far-UV CD and TEM results indicated the amorphous nature of SY-induced BLG aggregates. We believe that our results clearly suggest that SY dye effectively stimulates BLG aggregation.

11.
Antibiotics (Basel) ; 11(1)2022 Jan 03.
Article in English | MEDLINE | ID: mdl-35052936

ABSTRACT

The current study aimed to screen the preliminary phytochemicals in the leaf extract of the medicinal plant Simarouba glauca and to analyze its potential antimicrobial, antioxidant and anticancer properties. The phytochemical profile of the methanol extract was analyzed, and bioactive compounds were identified using chromatography, FTIR and GCMS. Antimicrobial activity and Minimum Inhibitory Concentration (MIC) were determined against 14 bacterial and 6 fungal strains. Moreover, the synergistic effect of a plant extract with commercially available antibiotics was also evaluated using the checkerboard method. The ethanolic and methanolic extracts showed exclusive activity against S. aureus and profound activity against E. coli and S. marcescens. Upon comparing breakpoints, methanolic extract demonstrated higher antimicrobial activity with a MIC value of 3.2 mg/mL against the test pathogens. Furthermore, the extracts demonstrated potential antioxidant activity; methanol extract had higher antioxidant potential compared to the ethanol extract. The major proactive bioactive compound with maximum antioxidant capacity was observed to be terpenoids. The methanol extract of S. glauca showed significant cytotoxicity against the MCF-7 breast cancer cell line with an IC50 value of 16.12 µg/mL. The overall results of our work provide significant evidence for the usage of methanolic extract of S. glauca as an efficient ethnomedicinal agent and a potential candidate for relieving many human ailments.

12.
J Nanobiotechnology ; 19(1): 401, 2021 Dec 04.
Article in English | MEDLINE | ID: mdl-34863214

ABSTRACT

Antibiotic resistance is spreading rapidly around the world and seriously impeding efforts to control microbial infections. Although nucleic acid testing is widely deployed for the detection of antibiotic resistant bacteria, the current techniques-mainly based on polymerase chain reaction (PCR)-are time-consuming and laborious. There is an urgent need to develop new strategies to control bacterial infections and the spread of antimicrobial resistance (AMR). The CRISPR-Cas system is an adaptive immune system found in many prokaryotes that presents attractive opportunities to target and edit nucleic acids with high precision and reliability. Engineered CRISPR-Cas systems are reported to effectively kill bacteria or even revert bacterial resistance to antibiotics (resensitizing bacterial cells to antibiotics). Strategies for combating antimicrobial resistance using CRISPR (i.e., Cas9, Cas12, Cas13, and Cas14) can be of great significance in detecting bacteria and their resistance to antibiotics. This review discusses the structures, mechanisms, and detection methods of CRISPR-Cas systems and how these systems can be engineered for the rapid and reliable detection of bacteria using various approaches, with a particular focus on nanoparticles. In addition, we summarize the most recent advances in applying the CRISPR-Cas system for virulence modulation of bacterial infections and combating antimicrobial resistance.


Subject(s)
Bacteria , Bacterial Infections , CRISPR-Cas Systems/genetics , Drug Resistance, Bacterial , Animals , Bacteria/genetics , Bacteria/pathogenicity , Bacterial Infections/diagnosis , Bacterial Infections/microbiology , Bacterial Infections/prevention & control , Drug Delivery Systems , Humans , Mice
13.
Appl Environ Microbiol ; 86(22)2020 10 28.
Article in English | MEDLINE | ID: mdl-32887715

ABSTRACT

Zinc oxide nanoparticles (ZnO NPs) are regarded as a safe and stable antimicrobial that can inactivate bacteria by several potential working mechanisms. We aimed to incorporate ZnO NPs into packaging material to control Campylobacter in raw chicken meat. ZnO NPs were first incorporated into three-dimensional (3D) paper tubes to identify the lethal concentration against Campylobacter jejuni, which was selected as the working concentration to develop 2D functionalized absorbing pads by an ultrasound-assisted dipping technique. The functionalized pad was placed underneath raw chicken meat to inactivate C. jejuni and the predominant chicken microbiota at 4°C within 8 days of storage. Immobilized ZnO NPs at 0.856 mg/cm2 reduced C. jejuni from ∼4 log CFU/25 g raw chicken meat to an undetectable level after 3 days of storage. Analysis by inductively coupled plasma-optical emission spectroscopy showed that the Zn level increased from 0.02 to 0.17 mg/cm2 in treated raw chicken meat. Scanning electron microscopy validated the absence of nanoparticle migration onto raw chicken meat after treatment. Inactivation of C. jejuni was associated with the increase of lactic acid produced by Lactobacillus in raw chicken meat in a pH-dependent manner. Less than 5% of Zn2+ was released from ZnO NPs at neutral pH, while up to 88% was released when the pH was <3.5 within 2 days. Whole-transcriptome sequencing (RNA-Seq) analysis demonstrated a broad effect of ZnO NPs on genes involved in various cellular developmental processes as annotated by gene ontology. Taken together, the results indicate that functionalized absorbing pads inactivated C. jejuni in raw chicken meat by immobilized ZnO NPs along with the controllable released Zn2+IMPORTANCE Prevalence of Campylobacter in raw poultry remains a major food microbiological safety challenge. Novel mitigation strategies are required to ensure the safety and quality of poultry products. Active food packaging can control pathogens without directly adding antimicrobials into the food matrix and extend the food's shelf life. The functionalized absorbing pad with ZnO NPs developed in this study was able to inactivate C. jejuni in raw chicken meat and keep the meat free from C. jejuni contamination during shelf life without any observed migration of nanoparticles. The controllable conversion of immobilized ZnO NPs to free Zn2+ makes this approach safe and eco-friendly and paves the way for developing a novel intervention strategy for other high-risk foods. Our study applied nanotechnology to exploit an effective approach for Campylobacter control in raw chicken meat products.


Subject(s)
Campylobacter Infections/prevention & control , Campylobacter jejuni/drug effects , Food Packaging/methods , Foodborne Diseases/prevention & control , Meat/microbiology , Metal Nanoparticles/administration & dosage , Zinc Oxide/administration & dosage , Animals , Chickens , Food Microbiology
14.
Front Cell Infect Microbiol ; 10: 615049, 2020.
Article in English | MEDLINE | ID: mdl-33585282

ABSTRACT

Campylobacter species are Gram-negative, motile, and non-spore-forming bacteria with a unique helical shape that changes to filamentous or coccoid as an adaptive response to environmental stresses. The relatively small genome (1.6 Mbp) of Campylobacter with unique cellular and molecular physiology is only understood to a limited extent. The overall strict requirement of this fastidious microorganism to be either isolated or cultivated in the laboratory settings make itself to appear as a weak survivor and/or an easy target to be inactivated in the surrounding environment of poultry farms, such as soil, water source, dust, surfaces and air. The survival of this obligate microaerobic bacterium from poultry farms to slaughterhouses and the final poultry products indicates that Campylobacter has several adaptive responses and/or environmental niches throughout the poultry production chain. Many of these adaptive responses remain puzzles. No single control method is yet known to fully address Campylobacter contamination in the poultry industry and new intervention strategies are required. The aim of this review article is to discuss the transmission, survival, and adaptation of Campylobacter species in the poultry production environments. Some approved and novel control methods against Campylobacter species throughout the poultry production chain will also be discussed.


Subject(s)
Campylobacter Infections , Campylobacter , Poultry Diseases , Animals , Campylobacter Infections/veterinary , Chickens , Poultry
15.
Front Microbiol ; 10: 1038, 2019.
Article in English | MEDLINE | ID: mdl-31139168

ABSTRACT

The aim of this study is to investigate the antimicrobial synergistic effect against Campylobacter jejuni, a leading foodborne pathogen that causes human gastroenteritis, by cinnamon oil, encapsulated curcumin, and zinc oxide nanoparticles (ZnO NPs). We compared three approaches to study the antimicrobial interactions, including the time-killing method, the fractional inhibitory concentration index (FICI) method, and a mathematical concentration-effect model. Isobologram analysis was performed to evaluate the synergy in different combinations, and a median-effect equation was applied to identify the combinations of synergistic effects at median, bacteriostatic, and bactericidal reduction levels. The time-killing method overestimated the synergistic interaction between antimicrobials, while the FICI method failed to detect an existing synergistic phenomenon. This lack of accuracy and sensitivity was mainly due to combining antimicrobials without a deep understanding of their concentration-effect relationships. Our results showed that each antimicrobial had a unique concentration-effect curve. Specifically, encapsulated curcumin showed a sharp sigmoidal curve unlike cinnamon oil and ZnO NPs. A mathematical model was applied to study the interaction between antimicrobials with a different shape of concentration-effect curve. We observed an additive effect of cinnamon oil/ZnO NPs and synergistic interactions of other binary combinations (cinnamon oil/encapsulated curcumin and ZnO NPs/encapsulated curcumin). The tertiary combination of cinnamon oil/ZnO NPs/encapsulated curcumin at IC25 (additive line <1-log CFU/mL) presented the greatest synergistic effect by reducing the bacterial population over 8-log CFU/mL. This mathematical model provided an alternative strategy to develop a new antimicrobial strategy.

16.
J Clin Diagn Res ; 10(5): QC06-9, 2016 May.
Article in English | MEDLINE | ID: mdl-27437307

ABSTRACT

INTRODUCTION: Aboriginal and Torres Strait Islander women are at increased risk of maternal morbidity and mortality as compared to non-Aboriginals. Similarly, aboriginal babies are at increased risk of low birth weight and infant mortality. AIM: To investigate the independent association of aboriginality with Tasmanian maternal and neonatal morbidity. MATERIALS AND METHODS: A retrospective analysis of all the births (gestation more than 20 weeks) from June 2013 to May 2014 was conducted at the Launceston General Hospital, Tasmania. The study compared 66 Aboriginal (4.2% of the total births) to 1477 non-aboriginal births for maternal and neonatal morbidity. Comparisons were made using logistic regression. The outcome measures were maternal and neonatal morbidity. RESULTS: Significantly higher number of aboriginal women (49% vs 19%; OR 4.15 90%CI 2.52- 6.85) smoked and used illicit drugs (15% vs 2%; OR 9.24; 95%CI 4.28-19.96) than the non-aboriginal women (both p<0.001). Maternal morbidity was not significantly different between aboriginal compared to non-aboriginal women (OR 0.64; 95%CI 0.36-1.14; p=0.13; adjusted OR 1.00; 95%CI 0.52-1.93; p=0.99). Factors positively associated with maternal morbidity included: age (OR 1.28; 95%CI 1.13-1.46; p<0.01) and BMI (OR 1.50; 95%CI 1.33-1.70; p<0.01). The unadjusted OR of neonatal morbidity for aboriginality was 1.98 (95%CI 1.17-3.34; p=0.01) and adjusted was 1.45 (95%CI 0.77-2.72; p=0.25). Factors positively associated with neonatal morbidity included smoking (OR 2.24; 95%CI 1.59-3.14; p<0.01), illicit drug use 95%CI 1.49-(OR 3.26; 95%CI 1.49-7.13; p <0.01), hypertension (OR 2.49; 95%CI 1.61-3.84; p<0.01) and diabetes (OR 1.92; 95%CI 1.33-2.78; p<0.01). CONCLUSION: The composite Aboriginal maternal morbidity does not differ, however the increased rates of smoking and illicit drug use are largely responsible for neonatal morbidity. Along with strengthening strategies to decrease medical comorbidities in aboriginals, we recommend intensifying smoking and illicit drug cessation programs.

17.
Int J Food Microbiol ; 217: 49-58, 2016 Jan 18.
Article in English | MEDLINE | ID: mdl-26490649

ABSTRACT

Due to lack of adequate control methods to prevent contamination in fresh produce and growing consumer demand for natural products, the use of bacteriophages has emerged as a promising approach to enhance safety of these foods. This study sought to control Listeria monocytogenes in cantaloupes and RTE meat and Escherichia coli O104:H4 in alfalfa seeds and sprouts under different storage conditions by using specific lytic bacteriophage cocktails applied either free or immobilized. Bacteriophage cocktails were introduced into prototypes of packaging materials using different techniques: i) immobilizing on positively charged modified cellulose membranes, ii) impregnating paper with bacteriophage suspension, and iii) encapsulating in alginate beads followed by application of beads onto the paper. Phage-treated and non-treated samples were stored for various times and at temperatures of 4°C, 12°C or 25°C. In cantaloupe, when free phage cocktail was added, L. monocytogenes counts dropped below the detection limit of the plating technique (<1 log CFU/g) after 5 days of storage at both 4°C and 12°C. However, at 25°C, counts below the detection limit were observed after 3 and 6h and a 2-log CFU/g reduction in cell numbers was seen after 24h. For the immobilized Listeria phage cocktail, around 1-log CFU/g reduction in the Listeria count was observed by the end of the storage period for all tested storage temperatures. For the alfalfa seeds and sprouts, regardless of the type of phage application technique (spraying of free phage suspension, bringing in contact with bacteriophage-based materials (paper coated with encapsulated bacteriophage or impregnated with bacteriophage suspension)), the count of E. coli O104:H4 was below the detection limit (<1 log CFU/g) after 1h in seeds and about a 1-log cycle reduction in E. coli count was observed on the germinated sprouts by day 5. In ready-to-eat (RTE) meat, LISTEX™ P100, a commercial phage product, was able to significantly reduce the growth of L. monocytogenes at both storage temperatures, 4°C and 10°C, for 25 days regardless of bacteriophage application format (immobilized or non-immobilized (free)). In conclusion, the developed phage-based materials demonstrated significant antimicrobial effect, when applied to the artificially contaminated foods, and can be used as prototypes for developing bioactive antimicrobial packaging materials capable of enhancing the safety of fresh produce and RTE meat.


Subject(s)
Biological Control Agents/pharmacology , Escherichia coli/growth & development , Food Contamination/prevention & control , Food Packaging/methods , Food Storage/methods , Listeria monocytogenes/growth & development , Myoviridae/metabolism , Alginates , Colony Count, Microbial , Cucumis melo/microbiology , Escherichia coli/virology , Glucuronic Acid , Hexuronic Acids , Listeria monocytogenes/virology , Meat/microbiology , Medicago sativa/microbiology , Temperature
18.
Eur J Paediatr Neurol ; 18(3): 391-8, 2014 May.
Article in English | MEDLINE | ID: mdl-24613244

ABSTRACT

UNLABELLED: Therapeutic hypothermia is the standard clinical practice for neonates with moderate to severe hypoxic ischaemic encephalopathy (HIE). AIM: To describe the two year neurodevelopmental outcomes of neonates who were routinely cooled using cool gel packs for HIE in Western Australia. METHODS: Retrospective study. Cases were identified from the neonatal databases. Information was collected from chart review. RESULTS: 65 infants received therapeutic hypothermia, of which 13 had mild, 35 moderate and 17 had severe HIE. There were no serious adverse effects attributable to cooling. All 13 infants with mild HIE survived, of whom developmental outcomes were available on nine; none had severe disability. Among 52 infants with moderate to severe HIE, there were nine deaths (17%) and developmental outcomes were available on 39; the incidence of severe disability was 23%. The risk of death or severe disability was 40% in infants with moderate to severe HIE. Physical growth was adequate at two years of age. CONCLUSIONS: Neonates undergoing therapeutic hypothermia with cool gel packs had both good survival rates and long term neurodevelopmental outcomes and met international benchmarks.


Subject(s)
Asphyxia Neonatorum/therapy , Developmental Disabilities/prevention & control , Hypothermia, Induced , Hypoxia-Ischemia, Brain/therapy , Asphyxia Neonatorum/mortality , Child, Preschool , Female , Gels , Humans , Hypoxia-Ischemia, Brain/mortality , Infant , Infant, Newborn , Male , Retrospective Studies , Treatment Outcome , Western Australia
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