Massively parallel combination screen reveals small molecule sensitization of antibiotic-resistant Gram-negative ESKAPE pathogens.

Antibiotic resistance, especially in multidrug-resistant ESKAPE pathogens, remains a worldwide problem. Combination antimicrobial therapies may be an important strategy to overcome resistance and broaden the spectrum of existing antibiotics. However, this strategy is limited by the ability to efficiently screen large combinatorial chemical spaces. Here, we deployed a high-throughput combinatorial screening platform, DropArray, to evaluate the interactions of over 30,000 compounds with up to 22 antibiotics and 6 strains of Gram-negative ESKAPE pathogens, totaling to over 1.3 million unique strain-antibiotic-compound combinations. In this dataset, compounds more frequently exhibited synergy with known antibiotics than single-agent activity. We identified a compound, P2-56, and developed a more potent analog, P2-56-3, which potentiated rifampin (RIF) activity against Acinetobacter baumannii and Klebsiella pneumoniae. Using phenotypic assays, we showed P2-56-3 disrupts the outer membrane of A. baumannii. To identify pathways involved in the mechanism of synergy between P2-56-3 and RIF, we performed genetic screens in A. baumannii. CRISPRi-induced partial depletion of lipooligosaccharide transport genes (lptA-D, lptFG) resulted in hypersensitivity to P2-56-3/RIF treatment, demonstrating the genetic dependency of P2-56-3 activity and RIF sensitization on lpt genes in A. baumannii. Consistent with outer membrane homeostasis being an important determinant of P2-56-3/RIF tolerance, knockout of maintenance of lipid asymmetry complex genes and overexpression of certain resistance-nodulation-division efflux pumps - a phenotype associated with multidrug-resistance - resulted in hypersensitivity to P2-56-3. These findings demonstrate the immense scale of phenotypic antibiotic combination screens using DropArray and the potential for such approaches to discover new small molecule synergies against multidrug-resistant ESKAPE strains.

Critical role of growth medium for detecting drug interactions in Gram-negative bacteria that model in vivo responses.

The rise in infections caused by multidrug-resistant (MDR) bacteria has necessitated a variety of clinical approaches, including the use of antibiotic combinations. Here, we tested the hypothesis that drug-drug interactions vary in different media, and determined which in vitro models best predict drug interactions in the lungs. We systematically studied pair-wise antibiotic interactions in three different media, CAMHB, (a rich lab medium standard for antibiotic susceptibility testing), a urine mimetic medium (UMM), and a minimal medium of M9 salts supplemented with glucose and iron (M9Glu) with three Gram-negative ESKAPE pathogens, Acinetobacter baumannii (Ab), Klebsiella pneumoniae (Kp), and Pseudomonas aeruginosa (Pa). There were pronounced differences in responses to antibiotic combinations between the three bacterial species grown in the same medium. However, within species, PaO1 responded to drug combinations similarly when grown in all three different media, whereas Ab17978 and other Ab clinical isolates responded similarly when grown in CAMHB and M9Glu medium. By contrast, drug interactions in Kp43816, and other Kp clinical isolates poorly correlated across different media. To assess whether any of these media were predictive of antibiotic interactions against Kp in the lungs of mice, we tested three antibiotic combination pairs. In vitro measurements in M9Glu, but not rich medium or UMM, predicted in vivo outcomes. This work demonstrates that antibiotic interactions are highly variable across three Gram-negative pathogens and highlights the importance of growth medium by showing a superior correlation between in vitro interactions in a minimal growth medium and in vivo outcomes. IMPORTANCE: Drug-resistant bacterial infections are a growing concern and have only continued to increase during the SARS-CoV-2 pandemic. Though not routinely used for Gram-negative bacteria, drug combinations are sometimes used for serious infections and may become more widely used as the prevalence of extremely drug-resistant organisms increases. To date, reliable methods are not available for identifying beneficial drug combinations for a particular infection. Our study shows variability across strains in how drug interactions are impacted by growth conditions. It also demonstrates that testing drug combinations in tissue-relevant growth conditions for some strains better models what happens during infection and may better inform combination therapy selection.

Show Me CKDintercept Initiative: A Collective Impact Approach to Improve Population Health in Missouri.

Ninety percent of people with chronic kidney disease (CKD) remain undiagnosed, most people at risk do not receive guideline-concordant testing, and disparities of care and outcomes exist across all stages of the disease. To improve CKD diagnosis and management across primary care, the National Kidney Foundation launched a collective impact (CI) initiative known as Show Me CKDintercept. The initiative was implemented in Missouri, USA from January 2021 to June 2022, using a data strategy, stakeholder engagement and relationship mapping, learning in action working groups (LAWG), and a virtual leadership summit. The Reach, Effectiveness, Adoption, Implementation, and Maintenance framework was used to evaluate success. The initiative united 159 stakeholders from 81 organizations (Reach) to create an urgency for change and engage new CKD champions (Effectiveness). The adoption resulted in 53% of participants committed to advancing the roadmap (Adoption). Short-term results reported success in laying a foundation for CI across Missouri. The long-term success of the CI initiative in addressing the public health burden of kidney disease remains to be determined. The project reported the potential use of a CI initiative to build leadership consensus to drive measurable public health improvements nationwide.

Adaptive preservation of orphan ribosomal proteins in chaperone-dispersed condensates.

Ribosome biogenesis is among the most resource-intensive cellular processes, with ribosomal proteins accounting for up to half of all newly synthesized proteins in eukaryotic cells. During stress, cells shut down ribosome biogenesis in part by halting rRNA synthesis, potentially leading to massive accumulation of aggregation-prone 'orphan' ribosomal proteins (oRPs). Here we show that, during heat shock in yeast and human cells, oRPs accumulate as reversible peri-nucleolar condensates recognized by the Hsp70 co-chaperone Sis1/DnaJB6. oRP condensates are liquid-like in cell-free lysate but solidify upon depletion of Sis1 or inhibition of Hsp70. When cells recover from heat shock, oRP condensates disperse in a Sis1- and Hsp70-dependent manner, and the oRP constituents are incorporated into functional ribosomes in the cytosol, enabling cells to efficiently resume growth. Preserving biomolecules in reversible condensates-like mRNAs in cytosolic stress granules and oRPs at the nucleolar periphery-may be a primary function of the Hsp70 chaperone system.

Allosteric site variants affect GTP hydrolysis on Ras.

RAS GTPases are proto-oncoproteins that regulate cell growth, proliferation, and differentiation in response to extracellular signals. The signaling functions of RAS, and other small GTPases, are dependent on their ability to cycle between GDP-bound and GTP-bound states. Structural analyses suggest that GTP hydrolysis catalyzed by HRAS can be regulated by an allosteric site located between helices 3, 4, and loop 7. Here we explore the relationship between intrinsic GTP hydrolysis on HRAS and the position of helix 3 and loop 7 through manipulation of the allosteric site, showing that the two sites are functionally connected. We generated several hydrophobic mutations in the allosteric site of HRAS to promote shifts in helix 3 relative to helix 4. By combining crystallography and enzymology to study these mutants, we show that closure of the allosteric site correlates with increased hydrolysis of GTP on HRAS in solution. Interestingly, binding to the RAS binding domain of RAF kinase (RAF-RBD) inhibits GTP hydrolysis in the mutants. This behavior may be representative of a cluster of mutations found in human tumors, which potentially cooperate with RAF complex formation to stabilize the GTP-bound state of RAS.

Serum Cholesterol Differences Between Statin Users Who Take Dietary Supplements and Those Who Do Not: NHANES 2013-2018.

Background: Cardiovascular disease (CVD) is the leading cause of mortality in the United States and statins are the most commonly prescribed medication. It is important to understand the potential impact supplements may have when taken in combination with statins on serum lipid outcomes. Objectives: To evaluate the differences in the concentrations of cholesterol, triacylglycerol (TAG), and HbA1c between adults who use statins alone and those who combine statins and dietary supplements. Methods: A cross-sectional analysis using data from US adults aged ≥20 years who participated in the NHANES (2013-2018). The serum concentrations of lipids and the HbA1c levels were compared using independent sample t-tests. All analyses were adjusted for the complex survey design and used appropriate sample weights. Results: Of 16,327 participants included in this analysis, 13% reported the use of statins alone, and 8.8% used statins and dietary supplements. Statin users who used dietary supplements tended to be women (50.5%), aged 65.8 ± 0.4 years, and were more likely to be White (77.4%). Participants who used statins in combination with dietary supplements were less likely to have higher levels of total cholesterol (5.1% ± 1.4% vs. 15.6% ± 2.7%, P < 0.001), HbA1c (6.0% ± 0.1% vs. 6.3% ± 0.1%, P < 0.05), and HDL cholesterol (50 ± 1.3 vs. 47 ± 0.8 mg/dL, P < 0.05) than those who used statins alone. No significant differences were identified between the two groups for LDL cholesterol and TAG concentrations. Conclusions: Statin users who coingested dietary supplements were less likely to have high levels of total cholesterol and HbA1c and greater HDL levels than statin users who did not take dietary supplements. Dietary intake, lifestyle choices, and other confounders may have influenced the observed outcome differences for those who took dietary supplements with statins and those who did not.

The Baby Bites Text Messaging Project with randomized controlled trial: texting to improve infant feeding practices.

Background: Rapid weight gain and overweight in infancy are associated with childhood obesity. Thus, effective, accessible interventions to promote healthy infant feeding practices to prevent early obesity are essential. Methods: This mixed-methods study involved diverse parents of infants in an urban, low-income pediatric clinic. Qualitative interviews explored parental attitudes towards feeding, early obesity, and communication with the pediatrician. A pilot, randomized controlled trial (RCT) informed by feedback provided by clinic parents compared text messages delivered for 12 months promoting healthy feeding practices to usual care to prevent early pediatric obesity. A computer-generated randomization schedule with balanced distribution for sex was used to place infants into groups. Weight-for-length percentiles and z-scores and feeding practices were measured at 0-2 weeks (baseline), 2-4 months, 6-9 months, and 12 months. Interviews were recorded, transcribed, and coded using thematic analysis. Weight for length percentile, Weight for length z scores, and feeding practices were compared between groups using repeated measures mixed analysis of variance (ANOVA). Results: Participants in the interviews were 15 parents of infants less than 1 month old. RCT participants were 38 parents of newborns (17 control; 21 intervention). Most parents in the qualitative evaluation viewed breastfeeding positively but also discussed barriers. Most also wanted practical information regarding infant feeding. There were no differences in weight-for-length percentile (F=0.52; P=0.60) or z-scores (F=0.7922; P=0.79), breastfeeding persistence χ2[1] =1.45, P=0.23, or age of introduction of solids in the intervention (statistical analysis not possible due to low counts) compared to the control group; however, low response to surveys limited the study's power. Conclusions: Text messaging has potential to extend the healthcare provider's communication beyond clinic. However, texting interventions should be flexible to mitigate barriers such as loss of phone service and challenges customizing messages to parent needs.

The small heat shock protein αB-Crystallin protects versus withaferin A-induced apoptosis and confers a more metastatic phenotype in cisplatin-resistant ovarian cancer cells.

Since a majority of ovarian tumors recur in a drug-resistant form leaving patients few treatment options, the goal of this study was to explore phenotypic and molecular characteristics of a cisplatin-resistant ovarian cancer cell line (OVCAR8R) as compared to its cisplatin-sensitive syngeneic counterpart (OVCAR8) and to explore the effectiveness of a novel chemotherapeutic, Withaferin A (WA). In addition to unique morphological characteristics, the small heat shock proteins (Hsps) αB-Crystallin (HspB5) and Hsp27 are constitutively expressed along with increased expression of vimentin in OVCAR8R cells, while OVCAR8 cells do not endogenously express these Hsps, supporting that Hsp overexpression may confer resistance to chemotherapy and promote more aggressive tumor types. WA increases apoptosis in a dose-dependent manner in OVCAR8 cells, while OVCAR8R cells remain more viable at comparable doses of WA coincident with the upregulation of αB-Crystallin. To determine the significance of αB-Crystallin in conferring a more aggressive phenotype, αB-Crystallin was silenced by CRISPR-Cas9 in OVCAR8R cells. The morphology of the OVCAR8R clones in which αB-Crystallin was silenced reverted to the morphology of the original cisplatin-sensitive OVCAR8 cells. Further, cisplatin-resistant OVCAR8R cells constitutively express higher levels of vimentin and migrate more readily than cisplatin-sensitive OVCAR8 and OVCAR8R cells in which αB-Crystallin was silenced. Transient overexpression of wildtype αB-Crystallin, but not a chaperone-defective-mutant, alters the morphology of these cells to closely resemble the cisplatin-resistant OVCAR8R cells and protects versus WA-induced apoptosis. Together, this research supports the potential effectiveness of WA as a therapy for ovarian cancer cells that have not yet acquired resistance to platinum-based therapies, and importantly, underscores that αB-Crystallin contributes to a more aggressive cellular phenotype and as such, may be a promising molecular target for a better clinical outcome.

Racial disparities and prevalence of cardiovascular disease risk factors, cardiometabolic risk factors, and cardiovascular health metrics among US adults: NHANES 2011-2018.

This study estimated the prevalence of cardiovascular disease (CVD) risk factors, cardiometabolic (CM) risk factors, and cardiovascular health metrics (CVHMs) among US adults and across race/ethnicity groups. The study comprised 8370 US adults aged ≥ 20 years from the National Health and Nutrition Examination Survey (NHANES) 2011-2018, free of coronary heart disease/heart failure, angina/angina pectoris, heart attack, and stroke, who provided complete data for the outcome variables of interest. Age-adjusted prevalence of CVD and CM risk factors, and CVHMs were computed for all adults and across race/ethnicity groups. All analyses accounted for the complex, multi-stage survey sampling design of the NHANES. Hypertension (45.0%), obesity (40.0%), fasting plasma glucose ≥ 100 mg/dL or hypoglycemic medication (51.0%), ideal physical activity (59.2%) and ideal smoking status (56.9%) were most prevalent for the whole sample. Mexican Americans and non-Hispanic Blacks had elevated risk for some, but not all, CVD and CM risk factors compared to non-Hispanic Whites and non-Hispanic Asians. Reducing further health disparities and persisting differences among racial and ethnic groups is vital to achieving the American Heart Association vision of all people having ideal cardiovascular health, living healthier and longer.

College Campus Food Pantry Program Evaluation: What Barriers Do Students Face to Access On-Campus Food Pantries?

The purpose of this study was to explore barriers Texas Woman's University (TWU) students face in accessing on-campus food pantries. This cross-sectional, survey-based study was conducted in Fall 2021. Students' use of the food pantries and barriers to utilization, including qualitative questions, were evaluated using descriptive statistics and thematic analyses. Students (n = 529) completed the survey. Despite a high prevalence of food insecurity (49.2%), most students reported never using the pantries (89.8%). Almost half of the students were unaware that these pantries existed on campus (47.8%). More than one in four students believed there were barriers to accessing the pantries, with time tissues, lack of transportation, limited food pantry hours of operation, and social stigma most commonly cited as major barriers to access. Food insecurity remains an urgent problem at TWU since the prevalence has remained high since 2019 despite the institutions' efforts to reduce it. One of those resources has not been utilized as expected, which might impede improvements in food security among students. TWU on-campus food pantries can use these findings to address major barriers by offering after-hours access through the libraries or campus police, partnering with public transportation, and normalizing accessing food assistance.

Factors associated with food security of Texas Woman's University freshmen.

OBJECTIVE: To investigate what factors are associated with food insecurity (FI) among freshman students and identify potential solutions. PARTICIPANTS: 73 freshman students. METHODS: Cross-sectional, Internet survey-based study. Fisher's Exact tests examined factors associated with food security (FS); Cohen's Kappa assessed the agreement between FI scores and self-assessment; thematic analysis used Nvivo 12. RESULTS: FI was 54.2% among the diverse students (65% non-white). Factors associated with FS included mother with a college degree (p = .018); father employed full-time (p < .001); identifying one's family financial situation as better than others (p = < .001); not obtaining personal student loans (p = 0.022). Students with FI tended to overestimate their FS status. Suggested solutions for FI included: improved finances, improved food accessibility, improved cooking skills. CONCLUSIONS: Future interventions should target freshmen who obtain personal student loans or have parents with less than a college degree or unstable employment status. (148).

Leveraging laboratory and clinical studies to design effective antibiotic combination therapy.

Interest in antibiotic combination therapy is increasing due to antimicrobial resistance and a slowing antibiotic pipeline. However, aside from specific indications, combination therapy in the clinic is often not administered systematically; instead, it is used at the physician's discretion as a bet-hedging mechanism to increase the chances of appropriately targeting a pathogen(s) with an unknown antibiotic resistance profile. Some recent clinical trials have been unable to demonstrate superior efficacy of combination therapy over monotherapy. Other trials have shown a benefit of combination therapy in defined circumstances consistent with recent studies indicating that factors including species, strain, resistance profile, and microenvironment affect drug combination efficacy and drug interactions. In this review, we discuss how a careful study design that takes these factors into account, along with the different drug interaction and potency metrics for assessing combination performance, may provide the necessary insight to understand the best clinical use-cases for combination therapy.

Influence of COVID-19 Pandemic Restrictions on College Students' Dietary Quality and Experience of the Food Environment.

The COVID-19 pandemic restrictions sent college students online and off campus, potentially reducing access to healthy food. The objective of this cross-sectional, internet-based study was to use qualitative and quantitative survey methods to evaluate whether COVID-19 pandemic restrictions in Texas, USA affected college students' ability to buy food, how/what they shopped for, how they prepared food, what they ate, how they felt about eating, and overall dietary quality (assessed using Healthy Eating Index [HEI] scores). Survey responses from 502 students (87.5% female; 59.6% nonwhite, mean age 27.5 ± 0.4 years, >50% graduate students) were analyzed. The qualitative analysis of open-ended questions revealed 110 codes, 17 subthemes, and six themes. Almost all students experienced changes in at least one area, the most common being changes in shopping habits. Participants with low or very low food security had lower HEI scores compared to food secure students (p = 0.047). Black students were more likely to report changes in their ability to buy food (p = 0.035). The COVID-19 restrictions varied in their impact on students' ability to access sufficient healthy food, with some students severely affected. Thus, universities should establish procedures for responding to emergencies, including identifying at-risk students and mobilizing emergency funds and/or food assistance.

Facilitating engagement of persons with opioid use disorder in treatment for hepatitis C virus infection via telemedicine: Stories of onsite case managers.

Although hepatitis C virus (HCV) infection has high prevalence and incidence in persons with opioid use disorder (PWOUD), their engagement in HCV care has been limited due to a variety of factors. In an ongoing multisite study at 12 opioid treatment programs (OTPs) throughout New York State (NYS), we have been evaluating telemedicine accompanied by onsite administration of direct acting antiviral (DAA) medications compared with usual care including offsite referral to a liver specialist for HCV management. Each site has a case manager (CM) who is responsible for all study-related activities including participant recruitment, facilitating telemedicine interactions, retention in care, and data collection. Our overall objective is to analyze CM experiences of clients' stories and events to understand how the telemedicine model facilitates HCV treatment. Hermeneutic phenomenology was used to interpret and to explicate common meanings and shared practices of the phenomena of case management, and a focus group with CMs was conducted to reinforce and expand on key themes identified from the CMs' stories. We identified three themes: (1) building trust, (2) identification of multiple competing priorities, and (3) development of personalized care approaches. Our results illustrate that trust is a fundamental pillar on which the telemedicine system can be based. Participants' experiences at the OTP can reinforce trust. Understanding the specific competing priorities and routinizing dedicated personalized approaches to overcome them are key to increasing participation in HCV care among PWOUD.

Specificity and Selective Advantage of an Exclusion System in the Integrative and Conjugative Element ICEBs1 of Bacillus subtilis.

Integrative and conjugative elements (ICEs) are mobile genetic elements capable of transferring their own and other DNA. They contribute to the spread of antibiotic resistance and other important traits for bacterial evolution. Exclusion is a mechanism used by many conjugative plasmids and a few ICEs to prevent their host cell from acquiring a second copy of the cognate element. ICEBs1 of Bacillus subtilis has an exclusion mechanism whereby the exclusion protein YddJ in a potential recipient inhibits the activity of the ICEBs1-encoded conjugation machinery in a potential donor. The target of YddJ-mediated exclusion is the conjugation protein ConG (a VirB6 homolog). Here, we defined the regions of YddJ and ConG that confer exclusion specificity and determined the importance of exclusion to host cells. Using chimeras that had parts of ConG from ICEBs1 and the closely related ICEBat1, we identified a putative extracellular loop of ConG that conferred specificity for exclusion by the cognate YddJ. Using chimeras of YddJ from ICEBs1 and ICEBat1, we identified two regions in YddJ needed for exclusion specificity. We also found that YddJ-mediated exclusion reduced the death of donor cells following conjugation into recipients. Donor death was dependent on the ability of transconjugants to themselves become donors and was reduced under osmoprotective conditions, indicating that death was likely due to alterations in the donor cell envelope caused by excessive conjugation. We postulate that elements that can have high frequencies of transfer likely evolved exclusion mechanisms to protect the host cells from excessive death.IMPORTANCE Horizontal gene transfer is a driving force in bacterial evolution, responsible for the spread of many traits, including antibiotic and heavy metal resistance. Conjugation, one type of horizontal gene transfer, involves DNA transfer from donor to recipient cells through conjugation machinery and direct cell-cell contact. Exclusion mechanisms allow conjugative elements to prevent their host from acquiring additional copies of the element and are highly specific, enabling hosts to acquire heterologous elements. We defined regions of the exclusion protein and its target in the conjugation machinery that convey high specificity of exclusion. We found that exclusion protects donors from cell death during periods of high transfer. This is likely important for the element to enter new populations of cells.

Prevalence and Social Determinants of Food Insecurity among College Students during the COVID-19 Pandemic.

The coronavirus disease (COVID-19) pandemic has increased unemployment and food insecurity in the United States (US). Prior to the pandemic, college students exhibited higher rates of food insecurity than nonstudent households. The objectives of this study were to assess the prevalence and determinants of food insecurity among college students during the COVID-19 pandemic. We administered an online survey to 651 students on three diverse campuses at a state-funded university in Texas, US, in May 2020. Food security was assessed using a multistep approach that included the 2-item Food Sufficiency Screener and 6-Item USDA Food Security Survey Module (FSSM). Overall, 34.5% of respondents were classified as food insecure within the last 30 days. The strongest predictors of food insecurity were change in current living arrangement (OR = 2.70, 95% CI: 2.47, 2.95), being furloughed (OR = 3.22, 95% CI: 2.86, 3.64), laid off (OR = 4.07, 95% CI: 3.55, 4.66), or losing part-time work (OR = 5.73, 95% CI: 5.09, 6.46) due to the COVID-19 pandemic. These findings highlight the high prevalence of food insecurity among college students during the COVID-19 pandemic, with students who experienced housing insecurity and/or loss of income due to the pandemic being impacted the most.

Parent preferences for text messages containing infant feeding advice.

BACKGROUND: Text-messaging is beneficial in health promotion. Research on impact of message framing (gain- versus loss-framed) has had variable results, depending on type of behavior targeted. There is no research on framing of text-messaging to promote healthful infant feeding practices. METHODS: The purpose of this cross-sectional survey was to examine whether parents of infants aged three months or younger viewed gain- or loss-framed text messages as more helpful and which style was viewed as more likely to affect feeding practices. A secondary purpose was to determine what time of day and frequency of messaging was preferred. Parents were recruited from an urban pediatric medical clinic. PsychData was used to administer the survey. Parents rated message pairs targeting constructs of the Health Belief Model using a five-point Likert scale. Paired t- tests compared overall ratings for helpfulness and likelihood of messages affecting feeding practices between gain- and loss-framed messages. Descriptive and frequency analyses were applied to demographics and questions regarding preferred timing for receiving messages. RESULTS: A total of 34 parents (3 fathers and 31 mothers, mean age 26±5.5 years) completed the survey, with 41% enrolled in WIC and 29% in SNAP. There was no overall difference in helpfulness or likelihood of messages affecting feeding practices between gain- and loss-framed messages. Message style did not affect likelihood of adopting a feeding practice. However, gain framed messages relating to benefits and self-efficacy for breastfeeding were viewed more positively (mean =2.32; P=0.034; mean =1.79; P=0.041, respectively). The greatest proportion of parents (38%) preferred receiving messages once per week, and 50% preferred morning messages. CONCLUSIONS: Framing of text messages appeared to have little effect on parents' acceptance of messages related to infant feeding practices. Parents were receptive to receiving messages from their infant's healthcare provider once per week, in the morning.

Advanced Glycation End Products and Risks for Chronic Diseases: Intervening Through Lifestyle Modification.

Advanced glycation end products (AGEs) are a family of compounds of diverse chemical nature that are the products of nonenzymatic reactions between reducing sugars and proteins, lipids, or nucleic acids. AGEs bind to one or more of their multiple receptors (RAGE) found on a variety of cell types and elicit an array of biologic responses. In this review, we have summarized the data on the nature of AGEs and issues associated with their measurements, their receptors, and changes in their expression under different physiologic and disease states. Last, we have used this information to prescribe lifestyle choices to modulate AGE-RAGE cycle for better health.

Identification, characterization and benefits of an exclusion system in an integrative and conjugative element of Bacillus subtilis.

Integrative and conjugative elements (ICEs) are mobile genetic elements that transfer from cell to cell by conjugation (like plasmids) and integrate into the chromosomes of bacterial hosts (like lysogenic phages or transposons). ICEs are prevalent in bacterial chromosomes and play a major role in bacterial evolution by promoting horizontal gene transfer. Exclusion prevents the redundant transfer of conjugative elements into host cells that already contain a copy of the element. Exclusion has been characterized mostly for conjugative elements of Gram-negative bacteria. Here, we report the identification and characterization of an exclusion mechanism in ICEBs1 from the Gram-positive bacterium Bacillus subtilis. We found that cells containing ICEBs1 inhibit the activity of the ICEBs1-encoded conjugation machinery in other cells. This inhibition (exclusion) was specific to the cognate conjugation machinery and the ICEBs1 gene yddJ was both necessary and sufficient to mediate exclusion by recipient cells. Through a mutagenesis and enrichment screen, we identified exclusion-resistant mutations in the ICEBs1 gene conG. Using genes from a heterologous but related ICE, we found that the exclusion specificity was determined by ConG and YddJ. Finally, we found that under conditions that support conjugation, exclusion provides a selective advantage to the element and its host cells.