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1.
Poult Sci ; 103(6): 103695, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38626693

ABSTRACT

This research assessed the impacts of dietary nano-propolis liposomes (NPRL) inclusion on the growth, blood biochemical components, immune function, and oxidative status of broilers exposed to cyclic heat stress (HS). Birds were fed with a basal diet supplemented with various levels of NPRL at 0 (HS), 100 (NPRL100), 250 (NPRL250) and 400 (NPRL400) mg/kg diets. Diets supplemented with NPRL significantly improved the growth indices and feed utilization, hemoglobin and red blood cells (P < 0.01). White blood cells, lymphocytes and monocytes were significantly decreased by NPRL inclusion (P < 0.001). Dietary supplementation of 250 or 400 mg of NPRL /kg reduced the pathogenic bacteria counts (Salmonella, E. coli and Enterococci) (P < 0.01). The birds fed diets with NPRL (400 mg/kg diet) significantly downregulated the mRNA IFNγ gene (p < 0.001), while both groups (NPRL100 and NPRL250) had similar results (P > 0.05). The iNOS gene was significantly decreased by the dietary NPRL inclusion in a dose-dependent manner. Birds in NRPL groups had inferior levels of the mRNA of interleukin-4 and tumor necrosis factor genes. The lysosome activity was significantly reduced by dietary 250 or 400 mg of NPRL inclusion (P < 0.001). Birds in NPRL250 and NPRL100 had greater IgG (P < 0.05) than the other groups. Regarding oxidative-related biomarkers, dietary NPRL inclusion decreased myeloperoxidase and malondialdehyde levels significantly compared to those with the HS group (P < 0.001). Broilers in the NPRL400 group had the lowest levels of total bilirubin and gamma-glutamyl transferase. NPRL250 had the lowest values of urea compared with other groups (P < 0.001). Dietary NPRL inclusion improved the broiler's hepatic and intestinal architecture exposed to cyclic heat stress. These results indicate that employing NPRL in the diets of stressed broilers can enhance heat resistance by enhancing blood metabolites and immunity, reducing inflammation and oxidative stress.


Subject(s)
Animal Feed , Chickens , Diet , Dietary Supplements , Liposomes , Animals , Chickens/physiology , Chickens/growth & development , Animal Feed/analysis , Liposomes/administration & dosage , Liposomes/chemistry , Diet/veterinary , Dietary Supplements/analysis , Male , Random Allocation , Heat-Shock Response/drug effects , Nanoparticles/administration & dosage , Nanoparticles/chemistry , Dose-Response Relationship, Drug , Poultry Diseases/prevention & control , Heat Stress Disorders/veterinary
2.
Life (Basel) ; 14(2)2024 Jan 28.
Article in English | MEDLINE | ID: mdl-38398699

ABSTRACT

Human viruses and viruses from animals can cause illnesses in humans after the consumption of contaminated food or water. Contamination may occur during preparation by infected food handlers, during food production because of unsuitably controlled working conditions, or following the consumption of animal-based foods contaminated by a zoonotic virus. This review discussed the recent information available on the general and clinical characteristics of viruses, viral foodborne outbreaks and control strategies to prevent the viral contamination of food products and water. Viruses are responsible for the greatest number of illnesses from outbreaks caused by food, and risk assessment experts regard them as a high food safety priority. This concern is well founded, since a significant increase in viral foodborne outbreaks has occurred over the past 20 years. Norovirus, hepatitis A and E viruses, rotavirus, astrovirus, adenovirus, and sapovirus are the major common viruses associated with water or foodborne illness outbreaks. It is also suspected that many human viruses including Aichi virus, Nipah virus, tick-borne encephalitis virus, H5N1 avian influenza viruses, and coronaviruses (SARS-CoV-1, SARS-CoV-2 and MERS-CoV) also have the potential to be transmitted via food products. It is evident that the adoption of strict hygienic food processing measures from farm to table is required to prevent viruses from contaminating our food.

3.
Pharmacol Res ; 200: 107050, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38159784

ABSTRACT

BACKGROUND: Immune responses play a significant role in hypertension, though the importance of key inflammatory mediators remains to be defined. We used a systematic literature review and meta-analysis to study the associations between key cytokines and incident hypertension. METHODS: We performed a systematic search of Pubmed/Medline, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials (CENTRAL), for peer-reviewed studies published up to August 2022. Incident hypertension was defined as systolic blood pressure ≥ 140 mmHg or diastolic blood pressure ≥ 90 mmHg and/or the use of antihypertensive medications. Random effects meta-analyses were used to calculate pooled hazard ratios (HRs)/risk ratios (RRs) and 95% confidence intervals by cytokine levels (highest vs. lowest quartile). RESULTS: Only IL-6 and IL-1ß levels have evidence allowing for quantitative evaluation concerning the onset of hypertension. Six studies (10406 participants, 2932 incident cases) examined the association of IL-6 with incident hypertension. The highest versus lowest quartile of circulating IL-6 was associated with a significant HR/RR of hypertension (1.61, 95% CI: 1.00 to 2.60; I2 =87%). After adjusting for potential confounders, including body mass index (BMI), HR/RR was no longer significant (HR/RR: 1.24; 95% CI, 0.96 to 1.61; I2 = 56%). About IL-1ß, neither the crude (HR/RR: 1.03; 95% CI, 0.60 to 1.76; n = 2) nor multivariate analysis (HR/RR: 0.97, 95% CI, 0.60 to 1.56; n = 2) suggested a significant association with the risk of developing hypertension. CONCLUSIONS: A limited number of studies suggest that higher IL-6, but not IL-1ß, might be associated with the development of hypertension.


Subject(s)
Cytokines , Hypertension , Humans , Antihypertensive Agents/therapeutic use , Blood Pressure , Cytokines/therapeutic use , Hypertension/epidemiology , Hypertension/drug therapy , Interleukin-1beta/pharmacology , Interleukin-6
4.
PLoS One ; 18(12): e0296114, 2023.
Article in English | MEDLINE | ID: mdl-38096192

ABSTRACT

[This corrects the article DOI: 10.1371/journal.pone.0293004.].

5.
PLoS One ; 18(10): e0293004, 2023.
Article in English | MEDLINE | ID: mdl-37856479

ABSTRACT

Online food delivery applications (OFD apps) provide consumers with a wide range of options to choose from. The present study aimed to assess the usage of OFD apps and investigate the factors that affect food choices with a special emphasis on healthy food choices and hygiene. A cross-sectional study among food delivery application users in Jordan was conducted using an online questionnaire between March and May 2022. A total of 675 eligible subjects participated in the study. Consumers' demographic characteristics, data on consumers' use of OFD apps, consumers' perceptions of healthy food availability in OFD apps, and consumers' attitudes toward food safety and delivery hygiene were collected and analyzed. About 64% of the studied sample used OFD apps weekly. Fast food was the most popular option for ordering (87.1%) and lunchtime was the most preferred time to order food (67.3%) for most of the respondents. Respondents' perceptions of a "healthy meal" was associated with the presence of a variety of vegetables in the meal. Food price, food appearance, time of delivery, macronutrient content information, the availability of healthy options, and considering vegetables as part of a healthy meal were determinants of consumer food choice (p<0.05). The findings suggest that the online food environment in Jordan was perceived to be unhealthy. Nevertheless, the convenient nature and the popularity of OFD apps hold great potential to promote healthy eating among consumers.


Subject(s)
Food Preferences , Food Safety , Humans , Cross-Sectional Studies , Vegetables , Diet, Healthy
6.
Eur J Heart Fail ; 25(7): 1094-1104, 2023 07.
Article in English | MEDLINE | ID: mdl-37211964

ABSTRACT

AIMS: Coronary artery disease (CAD) is a common cause of heart failure (HF). Whether coronary revascularization improves outcomes in patients with HF receiving guideline-recommended pharmacological therapy (GRPT) remains uncertain; therefore, we conducted a systematic review and meta-analysis of relevant randomized controlled trials (RCTs). METHODS AND RESULTS: We searched in public databases for RCTs published between 1 January 2001 and 22 November 2022, investigating the effects of coronary revascularization on morbidity and mortality in patients with chronic HF due to CAD. All-cause mortality was the primary outcome. We included five RCTs that enrolled, altogether, 2842 patients (most aged <65 years; 85% men; 67% with left ventricular ejection fraction ≤35%). Overall, compared to medical therapy alone, coronary revascularization was associated with a lower risk of all-cause mortality (hazard ratio [HR] 0.88, 95% confidence interval [CI] 0.79-0.99; p = 0.0278) and cardiovascular mortality (HR 0.80, 95% CI 0.70-0.93; p = 0.0024) but not the composite of hospitalization for HF or all-cause mortality (HR 0.87, 95% CI 0.74-1.01; p = 0.0728). There were insufficient data to show whether the effects of coronary artery bypass graft surgery or percutaneous coronary intervention were similar or differed. CONCLUSIONS: For patients with chronic HF and CAD enrolled in RCTs, the effect of coronary revascularization on all-cause mortality was statistically significant but neither substantial (HR 0.88) nor robust (upper 95% CI close to 1.0). RCTs were not blinded, which may bias reporting of the cause-specific reasons for hospitalization and mortality. Further trials are required to determine which patients with HF and CAD obtain a substantial benefit from coronary revascularization by either coronary artery bypass graft surgery or percutaneous coronary intervention.


Subject(s)
Coronary Artery Disease , Heart Failure , Percutaneous Coronary Intervention , Male , Humans , Female , Coronary Artery Disease/complications , Coronary Artery Disease/surgery , Heart Failure/drug therapy , Randomized Controlled Trials as Topic , Coronary Artery Bypass/adverse effects , Stroke Volume , Percutaneous Coronary Intervention/adverse effects , Treatment Outcome
7.
PLoS One ; 18(3): e0283513, 2023.
Article in English | MEDLINE | ID: mdl-36976823

ABSTRACT

Hybrid learning enables educators to incorporate elements of conventional face-to-face learning methods with structured online schemes. This study aimed to assess university students' perceptions of online and hybrid learning during the ongoing COVID-19 pandemic. A web-based cross-sectional study was conducted at the University of Sharjah, in the United Arab Emirates (n = 2056). Students' sociodemographic characteristics, perceptions of online and hybrid learning, concerns, and university life changes, were investigated. Perception statements were dichotomized into "positive" and "negative" based on a 50% cut-off point. Scores of > 7 and >5 indicated positive perceptions of online and hybrid learning respectively while scores of ≤ 7 and ≤ 5 indicated negative perceptions. Binary logistic regression analysis was performed to predict students' perceptions of online and hybrid learning according to demographic variables. Spearman's rank-order correlation was performed to determine the relationship between students' perceptions and behaviors. Most students preferred online learning (38.2%) and on-campus learning (36.7%) to hybrid learning (25.1%). Around two-thirds of the students had a positive perception of online and hybrid learning in terms of university support, however, half of them preferred the assessment during online or on-campus learning. Main difficulties reported in hybrid learning were lack of motivation (60.6%), discomfort when on-campus (67.2%), and distraction due to mixed methods (52.3%). Older students (p = 0.046), men (p<0.001), and married students (p = 0.001) were more likely to have a positive perception of online learning, while sophomore students were more likely to have a positive perception of hybrid learning (p = 0.001). In this study, most students preferred online or on-campus over hybrid learning and expressed certain difficulties while on hybrid learning. Future research should focus on investigating the knowledge and capability of graduates from a hybrid/online model compared to a traditional model. Obstacles and concerns should be considered for future planning to ensure the resilience of the educational system.


Subject(s)
COVID-19 , Pandemics , Male , Humans , Cross-Sectional Studies , COVID-19/epidemiology , Learning , Students
8.
Clin Res Cardiol ; 112(8): 1007-1019, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36241896

ABSTRACT

BACKGROUND AND AIMS: Congestion is a key driver of morbidity and mortality in heart failure. Implanted haemodynamic monitoring devices might allow early identification and management of congestion. Here, we provide a state-of-the-art review of implanted haemodynamic monitoring devices for patients with heart failure, including a meta-analysis of randomised trials. METHODS AND RESULTS: We did a systematic search for pre-print and published trials in Medline, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) on the 22nd of September 2021. We included randomised trials that compared management with or without information from implanted haemodynamic monitoring devices for patients with heart failure. Outcomes selected were hospitalisation for heart failure and all-cause mortality. Changes in treatment associated with haemodynamic monitoring resulted in only a small reduction in mean pulmonary artery pressure (typically < 1 mmHg as a daily average), which generally remained much greater than 20 mmHg. Haemodynamic monitoring reduced hospitalisations for heart failure (HR 0.75; 95% CI 0.58-0.96; p = 0.03) but not mortality (RR 0.92; 95% CI 0.68-1.26; p = 0.48). CONCLUSIONS: Haemodynamic monitoring for patients with heart failure may reduce the risk of hospitalization for heart failure but this has not yet translated into a reduction in mortality, perhaps because the duration of trials was too short or the reduction in pulmonary artery pressure was not sufficiently large. The efficacy and safety of aiming for larger reductions in pulmonary artery pressure should be explored. After selecting key words, a systematic review for implanted haemodynamic telemonitoring devices was performed in different dataset and 4 randomised clinical trials were identified and included in this meta-analysis. Three different devices (Chronicle, Chronicle/ICD and CardioMEMS) were tested. All-cause mortality and total heart failure hospitalisations were selected as outcomes. No reduction in all-cause mortality rate was reported but a potential benefit on total heart failure hospitalisation was identified.


Subject(s)
Heart Failure , Hospitalization , Humans , Heart Failure/diagnosis , Heart Failure/therapy , Hemodynamics , Monitoring, Physiologic , Randomized Controlled Trials as Topic
9.
Afr Health Sci ; 22(1): 80-87, 2022 Mar.
Article in English | MEDLINE | ID: mdl-36032464

ABSTRACT

Introduction: The main aim of this study was to explore the sources of consultation that women seek during premenstural syndrome (PMS), and to establish the association between the severity of PMS and how it affects the quality of life. Methods: Cross sectional study of 179 female patients, using an Arabic validated version of the shortened premenstrual assessment form, and a 7-item quality of life questionnaire that was developed by the researchers. The questionnaire was tested for validity and reliability via a pilot study before the initiation of data collection. Data was analyzed using SPSS version 19. Results: 179 women participated in the study, with more than half of them aged between 20-30 years old. PMS prevalence was 88%; patient's predominantly sought help from their relatives (51%), followed by physicians (34%). There was no association found between the severity of premenstrual symptoms and seeking consultation. PMS symptoms affected women's daily activities (p-value 0.039), their satisfaction with their general appearance (p-value 0.001) and weight (p-value 0.022), and affected their relationships with family members (p-value 0.001) and other people (p-value 0.002). Conclusion: PMS is a common condition that affects women and their quality of life in several ways. Physicians and primary health care providers must be more vigilant in detecting the presence of PMS.


Subject(s)
Premenstrual Syndrome , Quality of Life , Adult , Cross-Sectional Studies , Female , Humans , Pilot Projects , Referral and Consultation , Reproducibility of Results , Surveys and Questionnaires , Young Adult
10.
Heart Lung ; 56: 167-174, 2022.
Article in English | MEDLINE | ID: mdl-35933889

ABSTRACT

BACKGROUND: Improved outcomes for patients on mechanical ventilation may be achieved with early mobilization (EM). However, it is not clear how widely this strategy is adopted into routine intensive care unit (ICU) practice in Saudi Arabia. OBJECTIVES: This study was conducted to describe the present practices and challenges to providing EM for mechanically ventilated patients, which may drive dissemination and implementation activities. METHODS: We approached 205 ICUs across Saudi Arabia using a validated tool to assess ICU characteristics, the practices of EM for mechanically ventilated patients, and the barriers to providing EM. RESULTS: We approached 205 ICU persons in charge and achieved a 65% response rate (133 ICUs). The prevalence of EM for mechanically ventilated patients was 47% (63 ICUs). A total of 85 (64%) of the respondents reported having no previous training in EM. The absence of a written protocol was reported by 55% of the ICU practitioners in charge, 36% started EM within 2 to 5 days of critical illness, and 35% reported that performing EM for mechanically ventilated patients was totally dependent on physicians' orders. Forty-seven percent of the ICUs that practised EM had at least one coordinator or person in charge of facilitating EM. The highest level of EM with mechanically ventilated patients was 35/63 (55%) with patients remaining in-bed and 28/63 (45%) with patient getting out of bed. A majority of the respondents (39, 64%) performed EM once daily for an interval period of more than 15 min. Previous training in EM and years of experience of the ICU person in charge were significant factors that promoted EM for mechanically ventilated ICU patients (OR: 7.6 (3.37-17.26); p < 0.001 and OR: 1.07 (1.01-1.14), p = 0.004, respectively). Existing protocols increased the odds of starting EM within 2 to 5 days of critical illness by six-fold (OR: 6.03 (1.79-20.30); p = 0.004). No written guidelines/protocols available for EM, medical instability, and limited staff were the most common hospital-, patient- and health care provider-related barriers to EM in the ICUs, respectively. CONCLUSION: The prevalence of EM for mechanically ventilated patients across Saudi Arabia was 47%, although only 36% of the ICU staff had previous training in EM. Targeting modifiable barriers to EM, including a lack of training, guidelines and protocols, and staffing, will help to promote EM in Saudi Arabian ICUs.


Subject(s)
Early Ambulation , Respiration, Artificial , Humans , Saudi Arabia , Critical Illness , Intensive Care Units
11.
Cureus ; 14(6): e26345, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35775064

ABSTRACT

Glycogen storage disease type 2 (also known as Pompe disease) is a metabolic disorder characterized by an accumulation of glycogen within lysosomes. Pathophysiologically, this condition is caused by an autosomal recessive deficiency of the lysosomal acid alpha-glucosidase enzyme, resulting in defects in lysosomal metabolism. Glycogen accumulation causes advanced muscle weakness (myopathy) throughout the body, including the heart, skeletal muscles, liver, and the neurological system. Currently, there is no definitive treatment for Pompe disease. However, recent studies have indicated that enzyme replacement therapy (ERT) can be effective. Myasthenia gravis (MG) is an autoimmune illness that affects the postsynaptic acetylcholine receptors and causes fatigue that can be eased by rest. MG is frequently accompanied by a thymoma. Dyspnea and/or bulbar symptoms can indicate an imminent crisis requiring immediate intervention. Here, we present a rare case of a four-year-old female patient who initially presented at the age of one month with the infantile form of Pompe disease and congenital myasthenia syndrome type 5. The patient presented with bradycardia, poor suckling, respiratory distress, and respiratory failure requiring assisted ventilation, subglottic stenosis, and tachypnea. Whole exome sequencing was used for definitive diagnosis. ERT (Myozyme) was administered with good results. We propose that early identification and management of Pompe disease with Myozyme can improve patients' condition and ultimately increase the possibility of survival.

12.
Pharmacol Res ; 176: 106053, 2022 02.
Article in English | MEDLINE | ID: mdl-34979235

ABSTRACT

BACKGROUND: Administration of glucocorticoids might reduce mortality in patients with severe COVID-19 but have adverse cardiometabolic effects. OBJECTIVES: to investigate the effect of systemic administration of glucocorticoids on cardiovascular complications and all-cause mortality in patients hospitalised with respiratory viral infections, including COVID-19, SARS, MERS and influenza. METHODS: We identified randomised trials published prior to July 28th, 2021. The Mantel-Haenszel random effects method and the Hartung and Knapp adjustment were used to obtain pooled estimates of treatment effect with 95% confidence intervals. RESULTS: No randomised trials of glucocorticoids for SARS, MERS or influenza reported relevant outcomes. We included eleven COVID-19 randomised trials (8109 patients). Overall, compared to placebo or standard care, glucocorticoids were not associated with a reduction of in-hospital mortality (p = 0.09). In a pre-specified sub-analysis, in-hospital mortality was reduced by 19% when follow-up was restricted to 14 days from randomisation (5/11 trials, 1329 patients, p = 0.02). With longer follow-up (9/11 trials, 7874 patients), administration of glucocorticoids was associated with a trend to benefit for those requiring mechanical ventilation (RR 0.86; 95% CI 0.57-1.27) but possible harm for those not receiving oxygen at randomisation (RR 1.27; 95% CI 1.00 - 1.61), an effect that was significantly different amongst subgroups (p = 0.0359). Glucocorticoids reduced the risk of worsening renal function by 37% (4/11 trials); reported rate of other cardiovascular complications was low. CONCLUSIONS: Administration of systemic glucocorticoids to patients hospitalised with COVID-19 does not lower mortality overall but may reduce it in those requiring respiratory support and increase it in those who do not.


Subject(s)
COVID-19 Drug Treatment , Cardiovascular Diseases/etiology , Coronavirus Infections/drug therapy , Glucocorticoids/therapeutic use , Influenza, Human/drug therapy , Severe Acute Respiratory Syndrome/drug therapy , COVID-19/mortality , Cardiovascular Diseases/mortality , Coronavirus Infections/mortality , Hospitalization , Humans , Influenza, Human/mortality , Randomized Controlled Trials as Topic , SARS-CoV-2/drug effects
13.
Front Public Health ; 9: 729816, 2021.
Article in English | MEDLINE | ID: mdl-34527655

ABSTRACT

Objective: This study aimed to evaluate food safety knowledge, attitudes and practices (KAP) amongst university students in Jordan and changes in food-related behaviors during the COVID-19 pandemic. Correlation between food safety KAP scores and general characteristics of university students was also evaluated. Methods: A cross-sectional study was conducted where an Internet-based questionnaire was distributed through social media platforms. The sample consisted of 1,739 respondents from 29 Jordanian universities. The participants completed a 58-item questionnaire covering demographical characteristics and different food safety aspects which were namely "COVID-19 food-related attributes," "food cooking and storage," "personal hygiene." "cross-contamination prevention/disinfection procedures." and "restaurant hygiene." Descriptive statistics, Chi square tests and binary logistic analysis were used to assess the data. Results: The sample consisted of 67.2% females with a mean age of 21.3 ± 1.8 years. The average overall score of the tested aspects was 14.1/34.0 which corresponds to 41.3% of the questions being answered correctly. The percentage of correct answers of "COVID-19 food-related attributes," "food cooking and storage," "cross-contamination prevention/disinfection procedures," "personal hygiene" and "restaurant hygiene" was 56.8, 36.6, 28.4, 44.6. and 36.9%, respectively. A significant (P <0.05) association between respondents' food safety KAP scores and gender, marital status, university degree, employment status, self-rating of food safety knowledge, and the source of food safety information. Conclusion: University students in Jordan had insufficient KAP scores which is a concerning trend during the pandemic. Teaching fundamentals of food safety in the form of short courses/ lectures is recommended.


Subject(s)
COVID-19 , Universities , Adult , Cross-Sectional Studies , Female , Food Safety , Health Knowledge, Attitudes, Practice , Humans , Jordan/epidemiology , Male , Pandemics , SARS-CoV-2 , Students , Young Adult
14.
Saudi Med J ; 41(9): 938-946, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32893275

ABSTRACT

OBJECTIVES: To find reference data for the time of appearance of ossification centers in carpal bones and the lower ends of the radius and ulna in the Saudi population. In addition, to check the sequence of appearance of carpal bones and the relation of this sequence to the appearance of distal epiphyses of the radius and ulna. Methods: A retrospective radiological study was carried out between 2012 to 2020 at King Fahad Hospital of the University, Al-Khobar, Saudi Arabia. A sample of 279 hand/wrist plain radiographs of Saudi children was analyzed. RESULTS: The first bones at the wrist region to appear in Saudi children are the capitate, hamate, and distal epiphysis of the radius, and these appear during the first year of life. The other bones develop subsequently at yearly intervals, and the last one to appear is the pisiform, which arises at the end of the first decade of life. CONCLUSION: The sequence of appearance of carpal bones in the Saudi population is similar to what is described in the literature. However, the time of appearance of some of these bones is earlier than that in other populations.


Subject(s)
Bone Development/physiology , Carpal Bones/diagnostic imaging , Carpal Bones/physiology , Osteogenesis , Adolescent , Carpal Bones/anatomy & histology , Child , Child, Preschool , Epiphyses , Female , Humans , Infant , Male , Radius/anatomy & histology , Radius/diagnostic imaging , Retrospective Studies , Saudi Arabia , Sex Characteristics , Ulna/anatomy & histology , Ulna/diagnostic imaging
15.
Langmuir ; 36(30): 8947-8964, 2020 08 04.
Article in English | MEDLINE | ID: mdl-32633976

ABSTRACT

The roles of the bacterial surface biopolymers of pathogenic Listeria monocytogenes EGDe grown under variable pH conditions in governing their adhesion to a model surface of silicon nitride were investigated using atomic force microscopy under water. Our results indicated that the adhesion forces were the highest for cells cultured in media adjusted to pH 7 followed by 1.39, 1.49, 1.57, and 2.18-fold reductions at pH 6, 8, 9, and 5, respectively. Adhesion energies followed the same trends with 1.35, 1.67, 2.20, and 2.79-fold reductions in energies at pH 6, 8, 9, and 5, respectively, compared to the energy measured at pH 7. Furthermore, the structural properties of the bacterial surface biopolymer brush represented by the biopolymer brush thickness (Lo) and the molecular density (Γ) were determined by fitting a steric model of repulsion to the approach force-distance data. The Lo values followed the same trends as adhesion forces and energies, with thickness being highest at pH 7 followed by 1.82, 2.99, 3.11, and 4.66-fold reductions at pH 6, 8, 9, and 5, respectively. Γ was the highest at pH 5 and was followed by 1.26, 1.27, 1.70, and 2.82-fold reductions at pH 8, 9, 6, and 7, respectively. Our results indicated that bacterial adhesion forces and energies increased linearly with the product of Lo and Γ representing the number of biopolymers per unit length of the bacterial surface. To predict the adhesion forces and energies measured, a force-averaging model of the soft-particle analysis of the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory was used. In addition to the standard parameters accounted for in the soft-particle analysis of the DLVO theory such as surface potential, hydrophobicity, and size, this averaging model incorporates in it structural bacterial parameters such as Lo and Γ as well as a surface coverage factor (ϕ) that represents the fraction of the bacterial surface covered by biopolymers. When the soft-particle analysis of DLVO was considered, repulsive hydrogen bond strengths were predicted at close distances of approach (<0.3 nm). In comparison, the force-averaging model predicted that attractive hydrogen bonds dominate the bacterial adhesion strengths quantified. The highest adhesion quantified for cells grown at pH 7 was related to longer and more spaced biopolymers, higher contents of cellular carbohydrates, and more hydrophilic biopolymers, each of which contributes to higher possibilities for hydrogen bonding formation. These results are significant in designing new strategies that aim at controlling bacterial adhesion to surfaces.


Subject(s)
Listeria monocytogenes , Bacterial Adhesion , Hydrogen Bonding , Hydrogen-Ion Concentration , Microscopy, Atomic Force , Surface Properties
16.
ACS Omega ; 5(21): 12313-12319, 2020 Jun 02.
Article in English | MEDLINE | ID: mdl-32548414

ABSTRACT

Solution-processed organic-inorganic hybrid perovskites have attracted attention as light-harvesting materials for solar cells and photonic applications. The present study focuses on cubic single crystals and microstructures of CH3NH3PbBr3 perovskite fabricated by a one-step solution-based self-assembly method. It is seen that, in addition to the nucleation from the precursor solution, crystallization occurs when the solution is supersaturated, followed by the formation of a small nucleus of CH3NH3PbBr3 that self-assembles into bigger hollow cubes. A three-dimensional (3D) fluorescence microscopy investigation of hollow cubes confirmed the formation of hollow plates on the bottom; then, the growth starts from the perimeter and propagates to the center of the cube. Furthermore, the growth in the (001) direction follows a layer-by-layer growth model to form a complete cube, confirmed by scanning electronic microscopy (SEM) observations. Two-dimensional (2D)-3D fluorescence microscopy and photoluminescence (PL) measurements confirm a peak emission at 535 nm. To get more insights into the structural and optical properties, density functional theory (DFT) simulations were conducted. The electronic and optical properties calculated by DFT are in agreement with the obtained experimental values. The density-of-state (DOS) calculations revealed that the valence band maximum (VBM) consists of states contributed by Br and Pb, which agrees with the X-ray photoelectron spectroscopy valence band (XPS VB) measurements.

17.
Heart Lung ; 49(5): 630-636, 2020.
Article in English | MEDLINE | ID: mdl-32362397

ABSTRACT

BACKGROUND: Patient-ventilator asynchrony (PVA) is a prevalent and often underrecognized problem in mechanically ventilated patients. Ventilator waveform analysis is a noninvasive and reliable means of detecting PVAs, but the use of this tool has not been broadly studied. METHODS: Our observational analysis leveraged a validated evaluation tool to assess the ability of critical care practitioners (CCPs) to detect different PVA types as presented in three videos. This tool consisted of three videos of common PVAs (i.e., double-triggering, auto-triggering, and ineffective triggering). Data were collected via an evaluation sheet distributed to 39 hospitals among the various CCPs, including respiratory therapists (RTs), nurses, and physicians. RESULTS: A total of 411 CCPs were assessed; of these, only 41 (10.2%) correctly identified the three PVA types, while 92 (22.4%) correctly detected two types and 174 (42.3%) correctly detected one; 25.3% did not recognize any PVA. There were statistically significant differences between trained and untrained CCPs in terms of recognition (three PVAs, p < 0.001; two PVAs, p = 0.001). The majority of CCPs who identified one or zero PVAs were untrained, and such differences among groups were statistically significant (one PVA, p = 0.001; zero PVAs, p = 0.004). Female gender and prior training on ventilator waveforms were found to increase the odds of identifying more than two PVAs correctly, with odds ratios (ORs) (95% confidence intervals [CIs]) of 1.93 (1.07-3.49) and 5.41 (3.26-8.98), respectively. Profession, experience, and hospital characteristics were not found to correlate with increased odds of detecting PVAs; this association generally held after applying a regression model on the RT profession, with the ORs (95% CIs) of prior training (2.89 [1.28-6.51]) and female gender (2.49 [1.15-5.39]) showing the increased odds of detecting two or more PVAs. CONCLUSION: Common PVAs detection were found low in critical care settings, with about 25% of PVA going undetected by CCPs. Female gender and prior training on ventilator graphics were the only significant predictive factors among CCPs and RTs in correctly identifying PVAs. There is an urgent need to establish teaching and training programs, policies, and guidelines vis-à-vis the early detection and management of PVAs in mechanically ventilated patients, so as to improve their outcomes.


Subject(s)
Physicians , Respiration, Artificial , Critical Care , Female , Humans , Ventilators, Mechanical
18.
Colloid Polym Sci ; 292(2): 343-353, 2014 Feb 01.
Article in English | MEDLINE | ID: mdl-24563576

ABSTRACT

A new method to decoupling of bacterial interactions measured by atomic force microscopy (AFM) into specific and nonspecific components is proposed. The new method is based on computing the areas under the approach and retraction curves. To test the efficacy of the new method, AFM was used to probe the repulsion and adhesion energies present between L. monocytogenes cells cultured at five pH values (5, 6, 7, 8 and 9) and silicon nitride (Si3N4). Overall adhesion energy was then decoupled into its specific and nonspecific components using the new method as well as using Poisson statistical approach. Poisson statistical method represents the most commonly used approach to decouple bacterial interactions into their components. For all pH conditions investigated, specific energies dominated the adhesion and a transition in adhesion and repulsion energies for cells cultured at pH 7 was observed. When compared, the differences in the specific and nonspecific energies obtained using Poisson analysis and the new method were on average 2.2% and 6.7%, respectively. The relatively close energies obtained using the two approaches demonstrate the efficacy of the new method as an alternative way to decouple adhesion energies into their specific and nonspecific components.

19.
J Colloid Interface Sci ; 394: 554-63, 2013 Mar 15.
Article in English | MEDLINE | ID: mdl-23261349

ABSTRACT

Atomic force microscopy (AFM) was used to probe the mechanical and adherence properties of eight Listeria monocytogenes' strains representative of the species' two phylogenetic lineages I and II. From a functional perspective, lineage' I strains were characterized by lower overall adhesion forces and higher specific and nonspecific forces compared to lineage' II strains. From a structural perspective, lineage' II strains were characterized by higher Young's moduli and longer and stiffer biopolymers compared to lineage' I strains. Both lineages' I and II strains were similar in their grafting densities. Finally, our results indicated that epidemic and environmental strains of L. monocytogenes and irrespective of their lineage group were characterized by similar Young's moduli of elasticities and adhesion forces at the cellular level. However, at the molecular level, epidemic strains were characterized by higher specific and nonspecific forces, shorter, denser, and more flexible biopolymers compared to environmental strains.


Subject(s)
Listeria monocytogenes/cytology , Listeriosis/microbiology , Adhesins, Bacterial , Biomechanical Phenomena , Elastic Modulus , Humans , Listeria monocytogenes/chemistry , Listeria monocytogenes/genetics , Listeria monocytogenes/pathogenicity , Phylogeny
20.
J Inherit Metab Dis ; 32 Suppl 1: S41-4, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19165618

ABSTRACT

There are few reports of congenital disorders of glycosylation (CDGs) in the Asian population, although they have been reported worldwide. We identified a Malaysian infant female at 2 days of life with CDG type Ia. The diagnosis was suspected on the basis of inverted nipples and abnormal fat distribution. She had cerebellar hypoplasia and developed coagulopathy, hypothyroidism and severe pericardial effusion and died at 7 months of life. The diagnosis was supported by abnormal serum transferrin isoform pattern that showed elevated levels of the disialotransferrin isoform and trace levels of the asialotransferrin isoform. Enzyme testing of peripheral leukocytes showed decreased level of phosphomannomutase (PMM) activity (0.6 nmol/min per mg protein, normal range 1.6-6.2) and a normal level of phosphomannose isomerase activity (19 nmol/min per mg protein, normal range 12-25), indicating a diagnosis of CDG type Ia. Mutation study of the PMM2 gene showed the patient was heterozygous for both the common p.R141H (c.422T>A) mutation and a novel sequence change in exon 7, c.618C>A. The latter change is predicted to result in the replacement of the highly conserved phenylalanine residue at position 206 with a leucine residue (p.F206L) and occurs in the same codon as the previously reported p.F206S mutation. Analysis of 100 control chromosomes has shown that the p.F206L sequence change is not present, making it highly likely that this change is functionally important. To the best of our knowledge, this is the first report of CDG in the Malay population. Prenatal diagnosis was successfully performed in a subsequent pregnancy for this family.


Subject(s)
Congenital Disorders of Glycosylation/enzymology , Congenital Disorders of Glycosylation/genetics , Mutation , Phosphotransferases (Phosphomutases)/genetics , Amino Acid Sequence , Asian People/genetics , Congenital Disorders of Glycosylation/diagnosis , Exons , Fatal Outcome , Female , Genetic Counseling , Heterozygote , Humans , Infant , Infant, Newborn , Malaysia , Male , Molecular Sequence Data , Mutation, Missense , Phosphotransferases (Phosphomutases)/deficiency , Pregnancy , Prenatal Diagnosis , Sequence Homology, Amino Acid
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