Berry Pomace Extracts as a Natural Washing Aid to Mitigate Enterohaemorrhagic E. coli in Fresh Produce.

Enterohemorrhagic Escherichia coli (EHEC) outbreaks have been frequently linked to the consumption of produce. Furthermore, produce grown on organic farms possess a higher risk, as the farmers avoid antibiotics and chemicals. This study sets out to evaluate the effectiveness of advanced postharvest disinfection processes using berry pomace extracts (BPEs) in reducing EHEC load in two common leafy greens, spinach and lettuce. Spinach and lettuce were inoculated with ~5 log CFU/leaf EHEC EDL-933 and then treated with three different concentrations of BPE (1, 1.5, and 2 gallic acid equivalent, GAE mg/mL) for increasing periods of time. After the wash, the bacteria were quantified. Changes in the relative expression of virulence genes and the genes involved in cell division and replication and response against stress/antibiotics were studied. We observed a significant reduction in EHEC EDL933, ranging from 0.5 to 1.6 log CFU/spinach leaf (p < 0.05) washed with BPE water. A similar trend of reduction, ranging from 0.3 to 1.3 log CFU/mL, was observed in pre-inoculated lettuce washed with BPE water. We also quantified the remaining bacterial population in the residual treatment solutions and found the survived bacterial cells (~3 log CFU/mL) were low despite repeated washing with the same solution. In addition, we evaluated the phenolic concentration in leftover BPE, which did not change significantly, even after multiple uses. Alterations in gene expression levels were observed, with downregulation ranging from 1 to 3 log folds in the genes responsible for the adhesion and virulence of EHEC EDL933 and significant upregulation of genes responsible for survival against stress. All other genes were upregulated, ranging from 2 to 7 log folds, with a dose-dependent decrease in expression. This finding shows the potential of BPE to be used for sanitation of fresh produce as a natural and sustainable approach.

Effect modification of glycemic control on association of lung function with all-cause and cardiovascular mortality in persons with type 2 diabetes - A retrospective cohort study.

BACKGROUND: Poor glucose control might deteriorate the impaired pulmonary function, which can ultimately lead to mortality. However, few studies have examined the effect modification of glucose control on the association between pulmonary function and mortality. This study aimed to examine the association of pulmonary function with mortality and determine the effect modification of glycemic level on the association of pulmonary function with mortality in persons with type 2 diabetes (T2DM). METHODS: A retrospective cohort study included 3846 persons with T2DM with pulmonary function testing in Taiwan during 2002-2020. Expiratory volume in 1 s (FEV1) was measured as pulmonary function. Cox proportional hazards models were used and the effect modification of pulmonary function parameters and glucose control was assessed by their product terms. RESULTS: There were 733 deaths during an average follow-up of 7.83 years. Significant associations of FEV1 and mortality were found (hazards ratio [HR] for FEV1 Z-scores of <0 to -1, <-1 to -2 and <-2: 1.47 [1.20, 1.80], 2.48 [1.95, 3.14] and 3.07 [1.74, 5.44] compared with participants with Z-score ≥0, respectively. All p for trend<0.001). Significant effect modifications were found and the association between FEV1 and mortality was stronger in persons with good glycemic control compared with poor glycemic control (FEV1-FPG effect modification, P = 0.01; FEV1-HbA1c effect modification, P = 0.03). CONCLUSION: Pulmonary function, measured by FEV1, is significantly associated with mortality in persons with T2DM. Significant effect modification of glucose control on the association between pulmonary function parameters and mortality was found.

[Synergistic effect of Coptidis Rhizoma processed with Euodiae Fructus on ulcerative colitis through energy metabolism].

Based on the differences in targeted energy metabolomics, intestinal barrier protein expression, and glucose transport,the synergistic mechanism of Coptidis Rhizoma(CR) processed with Euodiae Fructus(ECR) on ulcerative colitis(UC) was explored.Mice were administered 4% dextran sulfate sodium to induce UC model, and then randomly divided into a model group, a CR group,and an ECR group. After 14 days of treatment, the therapeutic effect of processing on UC was assessed through histopathology of colon tissue and inflammatory indexes. Targeted energy metabolomics analysis was performed to evaluate the effect of processing on colon tissue energy metabolism. Molecular docking was carried out to predict the binding affinity of energy metabolites with intestinal barrier tight junction protein Claudin and glucose transporter 2(GLUT2). In vivo unidirectional intestinal perfusion experiments in rats were conducted to evaluate the effect of processing on intestinal glucose transport. The results showed that both CR and ECR could repair colon tissue damage in UC mice, downregulate tissue inflammatory factors interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α)levels, with the efficacy of ECR being superior to CR. Processed products significantly upregulated levels of multiple metabolites in colon tissue glycolysis, tricarboxylic acid cycle, and oxidative phosphorylation, among which the upregulated levels of 1,6-diphosphate fructose and acetyl coenzyme A could bind well with Claudin and GLUT2. Additionally, the processed product also increased the expression of GLUT2 and enhanced glucose transport activity. This study suggests that ECR may enhance glucose transport to improve colon energy metabolism, promote barrier repair, and exert synergistic effects through processing.

Investigating effectiveness of adherence of long-acting bronchodilator in chronic obstructive pulmonary disease with influenza infection.

Objectives: Long-acting bronchodilators are important treatments for chronic obstructive pulmonary disease (COPD) and adequate medication adherence decreases COPD exacerbations, especially in reducing the hazard of influenza infection. Therefore, the study aim was to evaluate adherence of long-acting bronchodilator treatment and the risk of influenza in patients with COPD. Methods: This retrospective nested case-control study included patients with newly diagnosed COPD from 2012 to 2018. Cases with influenza infection were defined and matched to 2 randomly selected controls. The influenza infection date was the index date. Conditional logistic regressions were used to estimate odds ratios of influenza from proportion of days covered (PDC) of long-acting bronchodilators measured in one year before the index date. Adherence was divided into high adherence (PDC ≥80 %) and low adherence (PDC <80 %). Results: This population-based study included 6,073 patients in the case group and 12,146 in the control group. High PDC of long-acting bronchodilators in COPD was associated with a 0.811-fold (95 % confidence interval: 0.754-0.883, P < 0.001) decreased influenza risk, where 906 (14.92 %) high PDC in case and 2,130 (17.54 %) in control. Low PDC without influenza vaccination in COPD patients is associated with increased influenza risk, regardless of exposure period. Conclusion: In Taiwan, COPD patients with high PDC were associate with lower COPD exacerbation. Different long-acting bronchodilator exposure or dose need to be further investigated in COPD patients.

Absence of PNET formation and normal longevity in a mouse model of Mahvash disease.

Mahvash disease, a rare autosomal recessive metabolic disorder characterized by biallelic loss-of-function mutations in the glucagon receptor gene (GCGR), induces significant pancreatic hyperglucagonemia, resulting in α-cell hyperplasia and occasional hypoglycemia. Utilizing CRISPR-Cas9 technology, we engineered a mouse model, designated as Gcgr V369M/V369M, harboring a homozygous V369M substitution in the glucagon receptor (GCGR). Although wild-type (WT) and Gcgr V369M/V369M mice exhibited no discernible difference in appearance or weight, adult Gcgr V369M/V369M mice, approximately 12 months of age, displayed a notable decrease in fasting blood glucose levels and elevated the levels of cholesterol and low-density lipoprotein-cholesterol. Moreover, plasma amino acid levels such as alanine (Ala), proline (Pro) and arginine (Arg) were elevated in Gcgr V369M/V369M mice contributing to α-cell proliferation and hyperglucagonemia. Despite sustained α-cell hyperplasia and increased circulating glucagon levels in Gcgr V369M/V369M mice, metabolic disparities between the two groups gradually waned with age accompanied by a reduction in α-cell hyperplasia. Throughout the lifespan of the mice (up to approximately 30 months), pancreatic neuroendocrine tumors (PNETs) did not manifest. This prolonged observation of metabolic alterations in Gcgr V369M/V369M mice furnishes valuable insights for a deeper comprehension of mild Mahvash disease in humans.

The effectiveness of endolysin ENDO-1252 from Salmonella bacteriophage-1252 against nontyphoidal Salmonella enterica.

Salmonella enterica (S. enterica) is the most common food and waterborne pathogen worldwide. The growing trend of antibiotic-resistant S. enterica poses severe healthcare threats. As an alternative antimicrobial agent, bacteriophage-encoded endolysins (endolysins) are a potential agent in controlling S. enterica infection. Endolysins are enzymes that particularly target the peptidoglycan layer of bacterial cells, leading to their rupture and destruction. However, the application of endolysins against Gram-negative bacteria is limited due to the presence of the outer membrane in the cell wall, which hinders the permeation of externally applied endolysins. This study aimed the prokaryotic expression system to produce the recombinant endolysin ENDO-1252, encoded by the Salmonella bacteriophage-1252 associated with S. Enteritidis. Subsequently, ENDO-1252 had strong lytic activity not only against S. Enteritidis but also against S. Typhimurium. In addition, ENDO-1252 showed optimal thermostability and lytic activity at 25°C with a pH of 7.0. In combination with 0.1 mM EDTA, the effect of 120 µg of ENDO-1252 for 6 hours exhibited the highest lytic activity, resulting in a reduction of 1.15 log or 92.87% on S. Enteritidis. These findings suggest that ENDO-1252 can be used as a potential and innovative antibacterial agent for controlling the growth of S. Enteritidis.

Corrigendum: Prescription pattern and effectiveness of antihypertensive drugs in patients with aortic dissection who underwent surgery.

[This corrects the article DOI: 10.3389/fphar.2023.1291900.].

Addressing causal relationship between drinking behavior and metabolic syndrome: one-sample Mendelian randomization analysis.

AIMS: Alcohol drinking is associated with central obesity, hypertension, and hyperlipidemia, which further causes metabolic syndrome (MetS). However, prior epidemiological studies on such associations lack experimental evidence for a causal relationship. This study aims to explore the causal relationship between drinking behavior and MetS in Taiwan population by using Mendelian randomization (MR) analysis. METHODS: A cross-sectional study was conducted using the Taiwan Biobank database, which comprised 50 640 Han Chinese who were 30-70 years old without cancer from 2008 to 2020. In MR analysis, we constructed weighted and unweighted genetic risk scores by calculating SNP alleles significantly associated with alcohol drinking. We calculated odds ratios and 95% confidence interval (CI) by using a two-stage regression model. RESULTS: A total of 50 640 participants were included with a mean age of 49.5 years (SD: 1.67 years), 36.6% were men. The adjusted odds ratio (aOR) of MetS per 5% increase in the likelihood of genetic predisposition to drink based on weighted genetic risk score with adjustment was 1.11 (95% CI: 1.10, 1.12, P < .001). Analysis was also conducted by grouping the likelihood of genetic predisposition to drink based on quartiles with multivariate adjustment. Using Q1 as the reference group, the aORs of MetS for Q2, Q3, and Q4 were 1.19 (1.12, 1.27, p < .001), 1.31 (1.23, 1.40, p < .001), and 1.87 (1.75, 2.00, p < .001), respectively, for the weighted genetic risk score. CONCLUSIONS: This study shows a modest relationship between drinking behavior and MetS by using MR analysis.

al-BERT: a semi-supervised denoising technique for disease prediction.

BACKGROUND: Medical records are a valuable source for understanding patient health conditions. Doctors often use these records to assess health without solely depending on time-consuming and complex examinations. However, these records may not always be directly relevant to a patient's current health issue. For instance, information about common colds may not be relevant to a more specific health condition. While experienced doctors can effectively navigate through unnecessary details in medical records, this excess information presents a challenge for machine learning models in predicting diseases electronically. To address this, we have developed 'al-BERT', a new disease prediction model that leverages the BERT framework. This model is designed to identify crucial information from medical records and use it to predict diseases. 'al-BERT' operates on the principle that the structure of sentences in diagnostic records is similar to regular linguistic patterns. However, just as stuttering in speech can introduce 'noise' or irrelevant information, similar issues can arise in written records, complicating model training. To overcome this, 'al-BERT' incorporates a semi-supervised layer that filters out irrelevant data from patient visitation records. This process aims to refine the data, resulting in more reliable indicators for disease correlations and enhancing the model's predictive accuracy and utility in medical diagnostics. METHOD: To discern noise diseases within patient records, especially those resembling influenza-like illnesses, our approach employs a customized semi-supervised learning algorithm equipped with a focused attention mechanism. This mechanism is specifically calibrated to enhance the model's sensitivity to chronic conditions while concurrently distilling salient features from patient records, thereby augmenting the predictive accuracy and utility of the model in clinical settings. We evaluate the performance of al-BERT using real-world health insurance data provided by Taiwan's National Health Insurance. RESULT: In our study, we evaluated our model against two others: one based on BERT that uses complete disease records, and another variant that includes extra filtering techniques. Our findings show that models incorporating filtering mechanisms typically perform better than those using the entire, unfiltered dataset. Our approach resulted in improved outcomes across several key measures: AUC-ROC (an indicator of a model's ability to distinguish between classes), precision (the accuracy of positive predictions), recall (the model's ability to find all relevant cases), and overall accuracy. Most notably, our model showed a 15% improvement in recall compared to the current best-performing method in the field of disease prediction. CONCLUSION: The conducted ablation study affirms the advantages of our attention mechanism and underscores the crucial role of the selection module within al-BERT.

Epidemiology of Osteoporosis in Patients with Chronic Obstructive Pulmonary Disease in Taiwan.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a preventable and treatable chronic condition characterized by progressive, partially reversible airflow obstruction. Osteoporosis represents a significant comorbidity in individuals with COPD. However, the incidence and prevalence of osteoporosis among the COPD population remain unclear in Taiwan. Therefore, our objective is to investigate the incidence and prevalence of osteoporosis in patients with COPD. METHODS: In this cross-sectional study, we enrolled a COPD population retrieved from the Taiwan National Health Insurance Research Database (NHIRD) spanning the years 2003 to 2016. Osteoporosis patients were identified using diagnosis codes. The study included newly diagnosed COPD patients from 2003 to 2016. The case group comprised patients who developed osteoporosis or osteoporotic fractures after their COPD diagnosis. We calculated the prevalence and incidence of osteoporosis in individuals with COPD and conducted trend tests. RESULTS: A total of 1,297,579 COPD patients were identified during the period from 2003 to 2016, with 275,233 of them in the osteoporosis group. The average prevalence of osteoporosis among individuals with COPD was 21.21% from 2003 to 2016 in Taiwan. The number of osteoporosis cases increased from 6,727 in 2003 to 24,184 in 2016. The prevalence of osteoporosis among COPD patients increased from 3.62% in 2003 to 18.72% in 2016. The number of osteoporosis cases among individuals with COPD continued to rise over the years, reaching its highest point in 2016 with 24,184 new cases. The incidence of osteoporosis fluctuated during the study period but generally remained around 3,000 cases per 100,000 person-years. Notably, there was a significant upward trend in incidence from 2003 to 2006, after which the trend stabilized and remained relatively constant. CONCLUSIONS: Our study highlights an increase in both the prevalence and incidence of osteoporosis in individuals with COPD. Given the significant medical, economic, and social implications associated with osteoporosis, a comprehensive and robust assessment of its healthcare burden can offer valuable insights for healthcare system planning and policymaking.

Mitochondrial DNA haplogroup D and brain microstructure regulate cognitive function among community-dwelling older adults.

INTRODUCTION: Maintaining physical and cognitive function among older adults is important. These functional states are affected by mitochondria through various mechanisms, such as cellular energy production and oxidative stress control. Owing to its involvement in the relations among the brain, cognition, and physical function, mitochondrial function may be affected by mitochondrial DNA (mtDNA) haplogroups. This study explored the effect of mtDNA haplogroups and brain microstructure on physical and cognitive functions among community-dwelling older adults. METHODS: This study was a community-based cross-sectional research. A total of 128 subjects aged 65 years and older without dementia completed several assessments, including mtDNA sequencing, physical and cognitive function tests, and magnetic resonance imaging (MRI) scans. Cognitive function and impairment were assessed by the MMSE and AD8 questionnaires. mtDNA haplogroups were classified by HaploGrep 2 software, and white matter microstructural integrity was scanned by 3T MRI. RESULTS: The mean age of the subjects was 77.3 years. After the adjustment for covariates, the mtDNA haplogroup D carriers showed significantly lower mini-mental state examination (MMSE) scores than other carriers (p = 0.047). Further considering the brain microstructure, the mtDNA haplogroup D (p = 0.002) and white matter volumes in the left precuneus corrected for total intracranial volumes (p = 0.014) were found to be independently influencing factors of the MMSE scores. CONCLUSIONS: The mtDNA haplogroup D and white matter microstructure regulated the cognitive function among community-dwelling older adults. The findings provide new insights into the research gap. Scientists must further venture into this field.

Panoramic three-dimensional optical digitization system assisted by a bi-mirror.

The digitization of objects' full surfaces finds widespread applications in fields such as virtual reality, art and design, and medical and biological sciences. For the realization of three-dimensional full-surface digitization of objects within complex sceneries, we propose a straightforward, efficient, and robust panoramic three-dimensional optical digitization system. This system contains a laser-based optical three-dimensional measurement system and a bi-mirror. By integrating mirrors into the system, we enable the illumination of the object from all angles using the projected laser beam in a single scanning process. Moreover, the main camera employed in the system can acquire three-dimensional information of the object from several different viewpoints. The rotational scanning method enhances the efficiency and applicability of the three-dimensional scanning process, enabling the acquisition of surface information of large-scale objects. After obtaining the three-dimensional data of the sample from different viewpoints using laser triangulation, mirror reflection transformation was employed to obtain the full-surface three-dimensional data of the object in the global coordinate system. The proposed method has been subjected to precision and validity experiments using samples with different surface characteristics and sizes, resulting in the demonstration of its capability for achieving correct three-dimensional digitization of the entire surface in diverse complex sceneries.

Effects of exogenous trehalose on filling characteristics and sugar component content of wheat under high temperature stress during the filling period.

Taking the heat-sensitive wheat variety 'Fanmai 5' (FM5) and the heat-tolerant variety 'Huaimai 33' (HM33), which were screened out in the previous experiments, as experimental materials, we conducted a field experiment with passive heat-enhancing shelters to simulate post-flowering high-temperature environment (average temperature increase of 5.13 ℃) during 2021-2022. During the filling period, we analyzed the effects of exogenous trehalose (10, 15 and 20 mmol·L-1) on the filling characteristics and sugar fraction under high temperature, with no spraying at ordinary temperature as control (CK). The results showed that treating without spraying exogenous trehalose at high temperature (H) significantly reduced wheat grain yield and grain weight during the filling period, and spraying exogenous trehalose alleviated the reduction of grain yield and grain weight at the filling stage under high temperature stress. Compared with the H treatment, grain yield and grain weight of HM33 and FM5 wheat varie-ties increased by 3.5%, 6.7% and 4.2%, 5.4%, respectively. High temperature stress significantly increased the trehalose content and trehalase (THL) activity in flag leaves of both wheat varieties, and decreased the fructose and glucose contents. Spraying exogenous trehalose increased the contents of trehalose, fructose, and glucose in flag leaves, and decreased the trehalase activity in flag leaves compared with H treatment, which could improve the glucose metabolism capacity of wheat at filling stage. The increasing effect of FM5 was higher than that of HM33. High temperature stress significantly reduced starch content of flag leaves and grains, while spraying exogenous trehalose alleviated the decrease of starch content of flag leaves and grains under high temperature stress, which was profit able for the substance accumulation of wheat grains under high temperature stress. Under the conditions of this experiment, spraying 15 mmol·L-1 trehalose at flowering stage was the best treatment for the two wheat varieties.

Prescription pattern and effectiveness of antihypertensive drugs in patients with aortic dissection who underwent surgery.

Background: Surgical patients with aortic dissection often require multiple antihypertensive drugs to control blood pressure. However, the prescription pattern and effectiveness of antihypertensive drugs for these patients are unclear. We aimed to investigate the prescription pattern and effectiveness of different classes of antihypertensive drugs in surgical patients with aortic dissection. Methods: Newly diagnosed aortic dissection patients who underwent surgery, aged >20 years, from 1 January 2012 to 31 December 2017 were identified. Patients with missing data, in-hospital mortality, aortic aneurysms, or congenital connective tissue disorders, such as Marfan syndrome, were excluded. Prescription patterns of antihypertensive drugs were identified from medical records of outpatient visits within 90 days after discharge. Antihypertensive drugs were classified into four classes: 1) ß-blockers, 2) calcium channel blockers (CCBs), 3) renin-angiotensin system, and 4) other antihypertensive drugs. Patients were classified according to the number of classes of antihypertensive drugs as follows: 1) class 0, no exposure to antihypertensive drugs; 2) class 1, antihypertensive drugs of the same class; 3) class 2, antihypertensive drugs of two classes; 4) class 3, antihypertensive drugs of three classes; or 5) class 4, antihypertensive drugs of four classes. The primary composite outcomes included rehospitalization associated with aortic dissection, death due to aortic dissection, and all-cause mortality. Results: Most patients were prescribed two (28.87%) or three classes (28.01%) of antihypertensive drugs. In class 1, ß-blockers were most commonly used (8.79%), followed by CCBs (5.95%). In class 2, ß-blockers+CCB (10.66%) and CCB+RAS (5.18%) were the most common drug combinations. In class 3, ß-blockers + CCB+RAS (14.84%) was the most prescribed combination. Class 0 had a significantly higher hazard of the composite outcome (HR, 2.1; CI, 1.46-3.02; p < 0.001) and all-cause mortality (HR, 2.34; CI, 1.56-3.51; p < 0.001) than class 1. There were no significant differences in hazards for rehospitalization associated with aortic dissection among classes. Conclusion: Among operated patients with type A aortic dissection, no specific type of antihypertensive drug was associated with a better outcome, whereas among those with type B aortic dissection, the use of ß-blockers and CCBs was related to a significantly lower risk of the composite outcome.

Photocatalytic Three-Component Reaction for the Synthesis of Multifunctional Diaryl Sulfides.

A photocatalytic three-component reaction of a nitroarene, a thiophenol, and a ketone for the synthesis of multifunctional diaryl sulfides was reported using a nitro group as the nitrogen source and thiophenol as the sulfur source. Thiophenol also serves as a proton donor to reduce nitroarene to arylamine as a key intermediate for the formation of C-N and C-S bonds. Good functional group tolerance and mild reaction conditions make this method have practical synthetic value for diversified multifunctional diaryl sulfides.

Coptidis Rhizoma processed with Evodia Rutaecarpa improves the effect on ulcerative colitis by increasing intestinal energy metabolites alpha-ketoglutarate and Lactobacillus reuteri.

BACKGROUND: Evodia Rutaecarpa-processed Coptidis Rhizoma (ECR) is a traditional Chinese medicine for the treatment of ulcerative colitis (UC) in China. However, the mechanisms underlying the ECR processing are not elucidated. PURPOSE: Coptidis Rhizoma (CR) regulates the gut microbiota in the treatment of gastrointestinal diseases. This study explored the mechanism of action of ECR before and after processing in UC in view of the regulation of gut microecology. STUDY DESIGN: A preclinical experimental investigation was performed using a mouse model of UC to examine the regulatory effect of ECR and its mechanisms through gut microbiota analysis and metabolomic assays. METHODS: Mice received 4% dextran sulfate sodium to establish a UC model and treated with ECR and CR. Colonic histopathology and inflammatory changes were observed. Gut microbiota was analyzed using 16 s rRNA sequencing. Transplants of Lactobacillus reuteri were used to explore the correlation between ECR processing and the gut microbiota. The expression of mucin-2, Lgr5, and PCNA in colonic epithelial cells was measured using immunofluorescence. Wnt3a and ß-catenin levels were detected by western blotting. The metabolites in the colon tissue were analyzed using a targeted energy metabolomic assay. The effect of energy metabolite α-ketoglutarate (α-KG) on L. reuteri growth and UC were verified in mice. RESULTS: ECR improved the effects on UC in mice compared to CR, including alleviating colonic injury and inflammation, and modulating gut microbiota by increasing L. reuteri level. L. reuteri dose-dependently alleviated colonic injury, increased mucin-2 level, and promoted colonic epithelial regeneration by increasing Lgr5 and PCNA expression. This was consistent with the results before and after ECR processing. L. reuteri promoted epithelial regeneration by upregulating Wnt/ß-catenin pathway. Moreover, ECR increased metabolites levels (especially α-KG) to promote energy metabolism in the colon tissue compared to CR. α-KG treatment increased L. reuteri level and alleviated mucosal damage in UC mice. It promoted L. reuteri growth by increasing the energy metabolic status by enhancing α-KG dehydrogenase activity. CONCLUSION: ECR processing improves the therapeutic effects of UC via the α-KG-L. reuteri-epithelial regeneration axis.

Arg177 and Asp159 from dog prion protein slow liquid-liquid phase separation and inhibit amyloid formation of human prion protein.

Prion diseases are a group of transmissible neurodegenerative diseases primarily caused by the conformational conversion of prion protein (PrP) from α-helix-dominant cellular prion protein (PrPC) to ß-sheet-rich pathological aggregated form of PrPSc in many mammalian species. Dogs exhibit resistance to prion diseases, but the mechanism behind the phenomenon remains poorly understood. Compared with human PrP and mouse PrP, dog PrP has two unique amino acid residues, Arg177 and Asp159. Because PrPC contains a low-complexity and intrinsically disordered region in its N-terminal domain, it undergoes liquid-liquid phase separation (LLPS) in vitro and forms protein condensates. However, little is known about whether these two unique residues modulate the formation of PrPC condensates. Here, using confocal microscopy, fluorescence recovery after photobleaching assays, thioflavin T binding assays, and transmission electron microscopy, we report that Arg177 and Asp159 from the dog PrP slow the LLPS of full-length human PrPC, shifting the equilibrium phase boundary to higher protein concentrations and inhibit amyloid formation of the human protein. In sharp contrast, His177 and Asn159 from the human PrP enhance the LLPS of full-length dog PrPC, shifting the equilibrium phase boundary to lower protein concentrations, and promote fibril formation of the canid protein. Collectively, these results demonstrate how LLPS and amyloid formation of PrP are inhibited by a single residue Arg177 or Asp159 associated with prion disease resistance, and how LLPS and fibril formation of PrP are promoted by a single residue His177 or Asn159. Therefore, Arg177/His177 and Asp159/Asn159 are key residues in modulating PrPC liquid-phase condensation.

Assessment of the prevalence, serotype, and antibiotic resistance pattern of Salmonella enterica in integrated farming systems in the Maryland-DC area.

Implementation of organic/pasture farming practices has been increasing in the USA regardless of official certification. These practices have created an increasingly growing demand for marketing safe products which are produced through these systems. Products from these farming systems have been reported to be at greater risk of transmitting foodborne pathogens because of current trends in their practices. Salmonella enterica (SE) is a ubiquitous foodborne pathogen that remains a public health issue given its prevalence in various food products, but also in the environment and as part of the microbial flora of many domestic animals. Monitoring antibiotic resistance and identifying potential sources contamination are increasingly important given the growing trend of organic/pasture markets. This study aimed to quantify prevalence of SE at the pre- and post-harvest levels of various integrated farms and sites in Maryland-Washington D.C. area, as well as identify the most prevalent serovars and antibiotic resistance patterns. Samples from various elements within the farm environment were collected and screened for SE through culture and molecular techniques, which served to identify and serotype SE, using species and serovar-specific primers, while antibiotic resistance was evaluated using an antibiogram assay. Results showed a prevalence of 7.80% of SE pre-harvest and 1.91% post-harvest. These results also showed the main sources of contamination to be soil (2.17%), grass (1.28%), feces (1.42%) and unprocessed produce (1.48%). The most commonly identified serovar was Typhimurium (11.32%) at the pre-harvest level, while the only identified serovar from post-harvest samples was Montevideo (4.35%). With respect to antibiotic resistance, out of the 13 clinically relevant antibiotics tested, gentamycin and kanamycin were the most effective, demonstrating 78.93 and 76.40% of isolates, respectively, to be susceptible. However, ampicillin, amoxicillin and cephradine had the lowest number of susceptible isolates with them being 10.95, 12.36, and 9.83%, respectively. These results help inform farms striving to implement organic practices on how to produce safer products by recognizing areas that pose greater risks as potential sources of contamination, in addition to identifying serotypes of interest, while also showcasing the current state of antibiotic efficacy and how this can influence antibiotic resistance trends in the future.