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Summary: Background: Approximately 20% of adults in Vietnam have hypertension, and management of this chronic condition remains challenging. This study aimed to assess the effectiveness of a multicomponent intervention in reducing blood pressure (BP) in adults with uncontrolled hypertension. Methods: This cluster randomised controlled trial was conducted in sixteen communities (8 intervention and 8 comparison) in a rural setting in Vietnam (2017–2022). Consenting adults (aged ≥ 18 years) with uncontrolled hypertension were enrolled. Sixteen communities were equally randomised to an intervention or comparison group stratified by district. Consenting adults were assigned to study groups by community. The comparison arm received training sessions about hypertension prevention and management for health workers, and patient education materials. The intervention arm received training sessions about hypertension prevention and management for health workers, and patient education materials and three enhancement components including a storytelling intervention, home BP self-monitoring, and expanded community health worker services. The primary outcome was the difference in changes in patient's levels of systolic BP between the study groups over a 12-month follow-up period. Patients and outcome assessors were masked. Findings: A total of 671 patients (340: intervention, 331: comparison) were enrolled in the trial. The mean age was 66 years and 45% were men. At the 12-month follow-up, the mean systolic BP declined by 18.4 mmHg in the intervention group and 3.7 mmHg in the comparison group (differential decline of 14.7 mmHg [95% CI: 11.8–17.6]). The intervention group also achieved better BP control and medication adherence than the comparison group. There were no serious adverse events related to study participation. Interpretation: The results of this trial demonstrate that a multicomponent intervention can effectively reduce elevated BP in individuals with uncontrolled hypertension in Vietnam. Trial registration: This trial was registered at ClinicalTrials.gov, NCT03590691. Funding: National Heart, Lung, and Blood Institute.

After schools were closed in AY 2019-2020 due to the COVID-19 pandemic, teachers were expected to continue two-way communication and collaboration with their students' families without much guidance. In this study, we focus on how five teacher candidates navigated and continued their efforts of communication and collaboration with students' families and the larger community during the pandemic. Through storytelling during interviews, the five teacher candidates provided valuable insight that focused on communication during the pandemic. Findings indicated that these teacher candidates struggled with establishing professional boundaries with students' families, wrestled with the unforeseeable challenges of "being" in the homes of their students' families, and experienced a disconnect from the community. Implications of this study suggest that lessons learned during COVID-19 could transform how teacher candidates and Educator Preparation Programs (EPPs) practice future two-way communication and collaboration with students' families.

Phage characterization for research and therapy can involve newly isolated phages propagated in pathogenic bacteria. If so, characterization requires safety-managing the bacteria. In the current study, we adapt a common and inexpensive reagent, PrimeStore (Longhorn Vaccines and Diagnostics, San Antonio, TX, USA), to safety-manage bacteria in 20 min by selectively inactivating the bacteria. No bacterial survivors are observed among >109 bacteria per ml for a representative of both Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Bacillus thuringiensis). This procedure causes no detected inactivation of podophage T3, myophage T4 and siphophage 0105phi7-2. Margins of safety for PrimeStore concentration exist for bacterial inactivation and phage non-inactivation. Thus, general applicability is expected. Subsequent dialysis is used to block long-term effects on phages. Nonetheless, comparable tests should be performed for each pathogenic bacterial strain/phage. Electron microscopy of thin sections reveals inactivation-altered bacterial cytoplasm and a non-disintegrated bacterial envelope (ghosts). Ghosting of E. coli includes re-arrangement of the cytoplasm and the release of endotoxin. The activity of the released endotoxin is >99% reduced after subsequent dialysis, which also removes PrimeStore components. Ghosting of B. thuringiensis includes apparent phase separation within the cytoplasm. The primary application envisaged is biophysical and other screening of phages for therapy of infectious disease.

Chemotherapy-inhibiting tumor cell evolution to drug-resistance is potentially suppressed by using a drug delivery vehicle (DDV) that has gating. Gating would be used to increase tumor-selectivity of delivery of DDV packaged drug. Tumor-selectivity increase would make possible increase in tumor-delivered drug dose, which would suppress opportunities to evolve drug resistance. Currently used DDVs do not have gating but gating is a natural feature of some bacteriophages (phages). Phage T4, which has recently been found highly persistent in murine blood, is a potential gated DDV. Thus, here, we proceed towards a T4-DDV by developing (1) improved procedure for generating high concentrations and amounts of phage T4, (2) elevated temperature-driven gate-opening and ethidium- and bleomycin-loading, and (3) purification of loaded T4 by rate zonal centrifugation. We test for loading by native agarose gel electrophoresis (AGE) with fluorescence detection. We observe loading in both phage T4 and T4 (tail-free) heads. The loaded particles have an openable, closed gate. Stored, mature T4 phages and phage heads do not release ethidium during at least a month at 4 °C and 6 days at 37 and 42 °C. Tumor-specific T4 phage delivery is projected via both the EPR effect and high T4 persistence.

Research is clear: Employers want college graduates who can communicate clearly, think analytically, and interact respectfully. Targeted educational experiences have measurably improved these capacities. To better prepare undergraduates, the University of Massachusetts Amherst developed the Community-Engaged Research Program, a pilot program featuring a cornerstone course. The course seeks to realize the goal of making research-based learning a standard in U.S. undergraduate education. Data from process evaluations, student assessments, and end-of-semester surveys show meaningful gains in students' ability to think through the research process, communicate research findings, and respectfully address others' needs. Recommendations for building a sustainable undergraduate research model are provided. With further institutional support, such courses could improve college graduate preparedness for the workforce.

BackgroundThere is a paucity of data on enteral and parenteral (EN and PN) nutrition support (NS) provided by nutrition and dietetic practitioners in adult acute care settings in Ghana. Furthermore, gray literature suggests that Ghanaian clinical nutrition professionals (CNPs) are seldom involved in advanced nutrition care teams.ObjectivesTo assess the knowledge, attitudes, and practices of Ghanaian CNPs regarding EN and PN.MethodsAn online cross-sectional survey was administered to Ghanaian CNPs ahead of a professional development workshop on EN and PN Support. Participants were asked questions about initiation and timing of NS, and knowledge on availability of commercial formula. A 5-point Likert scale was used to assess self-efficacy in using EN and PN. To assess practical knowledge on EN and PN, participants were asked to identify whether EN or PN was indicated for seven short case scenarios. Open-ended questions were used to assess reasons for participant self-ratings.ResultsA total of 76 dietitians, nutritionists, students, and interns completed the survey. For EN, self-efficacy scores were lowest for the calculation of enteral goal rate, and goal volume (mean 3.20 ± 1.27), and writing of EN prescriptions (mean 3.07 ± 1.29). Self-efficacy scores for the formulation of alternative formulas in lieu of commercial formula were the highest (3.63 ± 1.36). For PN, self-efficacy scores for all domains were lower than 3, with the lowest scores observed for writing PN prescriptions (2.19 ± 1.14) and determining micronutrient additives (2.12 ± 1.04). We identified limited training and lack of practical exposure to NS, limited ability to effectively monitor tube feeds, and prohibitive cost and limited availability of EN and PN formula among the barriers impacting self-efficacy scores.ConclusionGiven the vital role that CNPs play in the delivery of EN and PN, it is important to develop professional training programs especially focused on PN to bridge knowledge and practice gaps.

The following hypothesis proposes non-diffusive, environmental bacteriophage (phage) motion. (1) Some phage-hosting, motile bacteria undergo chemotaxis down ATP concentration gradients to escape lysis-inducing conditions, such as phage infection. (2) Some phages respond by non-infective binding to the motile bacteria. (3) When the bacteria reach a lower ATP concentration, which is a condition that signals increased density of phage-susceptible bacteria, the phage converts, Trojan-horse-like, to productive binding and infection. This hypothesis was previously proposed for Bacillus thuringiensis siphophage 0105phi7-2. It is tested here and confirmed with the following observations. (1) B. thuringiensis is found, macroscopically, preferentially located at low ATP concentrations when propagated in-gel after inoculation in the center of an artificially generated ATP concentration gradient. (2) Inoculating phage 0105phi7-2 at the bacteria inoculation site, 2–3 h after inoculation of bacteria, results in cell lysing activity that moves with the bacteria, without a visible trail of lysis. Trojan-horse-like behavior is consistent with only biofilm-inhabiting phages because environmental selection for this behavior requires limited fluid flows. We propose using artificial ATP concentration gradients to instigate Trojan-horse-like phage behavior during phage therapy of bacterial biofilms.

Adaptation of plant and human pathogenic bacteria to niches of existence differing from their original ones is a sophisticated mechanism for survival. Research indicates that certain plant bacterial pathogens are capable of causing disease in humans, and some human bacterial pathogens can inhabit the plant environment and cause disease in plants. The infection of humans by plant bacteria may occur at direct physical contact with diseased plants and/or via the respiratory tract in mainly immunocompromised or otherwise stressed individuals. Indirect transmitters of plant and human microbes can be wind, rain, dust, insects, and animals. Human pathogenic bacteria may contaminate the soil and irrigation water, colonize the rhizosphere, more rarely also the phyllosphere, and can survive as epiphytes. Thus, the plant environment may become a reservoir of human pathogens. A source of foodborne human pathogenic bacteria can be unprocessed or unwashed fruits and vegetables. Especially during the last decade, the processes underlying the cross-kingdom performance of pathogenic bacteria are intensively researched. However, in reality, the risk for human health at infections by plant bacteria and by human bacterial pathogens surviving in the plant environment is still underestimated. The goal of the current review is to increase the interest in these issues in agricultural and general environments. Some basic strategies for infection and symptoms of diseases caused by the microorganisms under consideration are described. The potency of certain plant bacterial pathogens to surpass barriers towards humans and the interaction of human bacterial pathogens with the plant environment are addressed and the existing information is critically discussed.

Abstract Background Chronic stress is implicated in behavioral and health issues in cats, but methods for recognition, evaluation, and measurement of stress are lacking. Cortisol concentration is typically used as an indicator of stress. Objectives To evaluate use of an enzyme immunoassay to quantitate hair and nail cortisol concentrations (HCC and NCC) in cats and evaluate associations between HCC and NCC and behavioral, physical, and environmental correlates of chronic stress in cats. Animals Forty‐eight adult, owned or community cats. Methods Cross‐sectional study. Nail clippings and hair were collected from cats. Medical history and cat daily lifestyle questionnaires were completed by owners or caretakers. A commercial laboratory performed cortisol extraction and quantification using a validated enzyme immunoassay kit. Correlational and regression analyses were used to evaluate associations between HCC and NCC and behavioral, environmental, and medical factors. Results Hair and nail cortisol concentrations were significantly associated (rs = 0.70; P

Recent immigration trends at the national and local levels indicate that schools are receiving the largest influx of immigrant students since the beginning of the 20th century. According to the U.S. Department of Education (2014), English language learners (ELLs) accounted for nearly 4.4 million students during the 2011-2012 school year. These students often enter schools and classrooms with teachers who feel underprepared to meet their complex needs. Literature suggests that preservice teachers' backgrounds often affect the degree to which prospective teachers support multicultural education and the degree to which they wish to explore social inequalities. Given the need to better prepare preservice teachers for the diverse classroom, the purpose of this study was to explore the attitudes of undergraduate teacher education candidates after one required multicultural course that focused on the educational experiences of ELLs. Qualitative data were collected in the form of student narratives in order to explore the ways that these undergraduate students' beliefs evolved over one semester. The study was guided by the following research questions: (1) Which course activities contributed most to the perceived changes of undergraduate preservice teacher beliefs toward English Language Learners?; and (2) How did teacher education candidates' perceived beliefs toward ELLs evolve? This study indicated that most of the teachers in this course were able to narrate their perceived shifts in thinking about ELLs through a thoughtful course design including a semester-long clinical experience working with ELLs. This research adds to the larger discourse on exactly what can be done to develop teachers' beliefs, and to what extent a single semester of reflective coursework can be successful.

BackgroundHealth literacy (HL) has shown its important role on reducing the burden of heart diseases. However, no study has provided a comprehensive worldwide view of the data regarding HL and heart diseases. The study aimed to provide insight into: (1) the intellectual structure, (2) research trends, and (3) research gaps on HL and heart diseases; and (4) to explore HL scales commonly utilized in heart studies.Materials and methodsStudies related to HL and heart diseases were retrieved from Web of Science, Scopus, and PubMed. All publications published between 2000 and 2021 were included after conducting keyword searches on “heart diseases” in general or on specific types of heart diseases (e.g., “heart failure”) and “health literacy”. Bibliometric analyses were carried out using the Bibliometrix R package and VOSviewer 1.6.14.FindingsA total of 388 original research articles and reviews on HL and heart diseases were included in our study. The studies were primarily conducted in the United States and developed countries. A total of 337 studies (86.9%) focused on heart failure (200 studies, 51.5%) and ischemic heart diseases (137 studies, 35.3%). Sixty-two studies (16.0%) focused on other heart diseases (e.g., valvular diseases and rheumatic heart diseases). The number of interventional studies was limited (52 studies, 13.4%) and fluctuated from 2000 to 2021. The most common questionnaires measuring health literacy among patients with heart diseases were the Test of Functional Health Literacy in Adults (TOFHLA), Short Test of Functional Health Literacy in Adults (STOFHLA), and Brief Health Literacy Screen (BHLS). Use of the eHealth Literacy Scale (eHEALS) has become the latest trend among patients with heart diseases.ConclusionHealth literacy and heart diseases were most often studied in the United States and developed countries. Several HL tools were used; eHEALS has been lately used in this field. These findings suggest the need to conduct more empirical studies on HL and heart diseases in different settings (e.g., developing or poor countries) and with different types of heart diseases (e.g., valvular and rheumatic disorders). Additionally, it is necessary to develop heart disease-specified HL scales for research and practice.

Background and Objectives There are growing numbers of older adults with long-term vision impairment who are likely to experience everyday activity challenges from their impairment in conjunction with age-related changes. Technology has potential to support activity engagement. To develop effective technologies and interventions, we need to understand the context of activity challenges and identify unmet support needs. Research Design and Methods The Aging Concerns, Challenges, and Everyday Solution Strategies (ACCESS) study is a mixed-method approach to explore everyday challenges of people aging with long-term disabilities. Participants included 60 adults aging with long-term vision impairment (63% female; M age = 67, SD  = 4.6) who completed in-depth, structured interviews exploring the nature of everyday challenges and their unmet support needs for activity engagement. We conducted a content analysis using a deductive and inductive approach to build a detailed coding scheme of challenge codes and subcodes. Results The analyses provided detailed insights about the nature of challenges people aging with vision impairment experience when performing specific instrumental activities of daily living (IADLs) in the context of home maintenance, transportation, shopping/finance, and managing health. Vision-related challenges and participation restrictions were identified for several activities that require reading, navigation, and identification (e.g. shopping, medication management, public transportation). Emergent challenge themes for performing IADLs included personal limitations (e.g. physical, cognitive, financial) and environmental barriers (e.g. accessibility, technology, transportation). Discussion and Implications Contextual examples of IADL challenges among individuals aging with vision impairment highlight opportunities for technology design and innovation to support participation in everyday activities. [ABSTRACT FROM AUTHOR]

Continental margin sediments represent a major global sink of organic carbon (OC), and as such exert a key control on Earth’s climate. Today, OC burial in marine sediments mainly takes place under oxygen-rich water columns, where most OC is stabilized through intimate association with sediment grains and biogenic minerals. In prior episodes of Earth’s past, when large parts of the oceans were anoxic, the mode of sedimentary OC burial must have been very different, however. Present-day analogues indicate that surface sediments accumulating under low-oxygen water columns are often “soupy” in texture. Moreover, most OC occurs in large (100–2,000 μm diameter) organic and organo-mineral aggregates which, due to their low density, are prone to wave- and current-induced resuspension. Upon mobilization, these aggregates can undergo lateral transport within so-called nepheloid layers, and may be translocated hundreds of kilometres, and on timescales of thousands of years. Little is known about processes of formation, resuspension and hydrodynamic properties of these aggregates in oxygen-poor waters, or which factors control their eventual breakdown or burial. The goal of this study is to examine the drivers and biogeochemical consequences of this resuspension on OC cycling in modern, oxygen-depleted, “Semi-Liquid Ocean Bottom” (SLOB) regions. We argue that models of sediment and OM hydrodynamics and redistribution that describe sedimentation processes in oxygenated ocean waters of the modern ocean are a poor analogue for equivalent processes occurring under oxygen-deficient conditions. In the latter, we hypothesize that 1) the abundance of low-density organic-rich particles and aggregates leads to a greater propensity for sediment remobilization at low(er) shear stress, and 2) upon resuspension into low-oxygen bottom waters, remobilized OM may be subject to less degradation (less attenuation) during lateral transport, leading to efficient and widespread translocation to distal centres of deposition. We address specific aspects of the SLOB hypothesis utilizing a combination of literature and new data, focussing on the Benguela Upwelling Region as a model system.

The authors discuss why the current conceptual base of project management research and practice continues to attract criticism since it does not adequately address the complexity that leads to software-project failure. To do so, the study explores systems thinking and artificial neural networks to shed light on complexity in software-project behavior using nonlinear functional relationships between critical success factors and project success to utilize their connectedness as an approach in order to create project-outcome prediction models. The artificial neural networks were used to create two project-outcome prediction models: one for a binary classification task to discriminate failed from successful projects using a multi-input-single-output configuration and one for a multi-task binary classification to discriminate success from failure in multiple project-success dimensions using a multi-input multi-output configuration. The results yielded high-performance values for a binary classification task, performed to predict overall project success, and slightly lower performance values for the multi-task binary classification, which was also performed to predict success in project-success dimensions. It was found that the nonlinear behavior of critical success factors may be used to create prediction models, by embedding equifinality and connectedness constructs that prove to be useful to understand projects as complex, multi-loop, and nonlinear systems. Further research is needed to investigate the causality between critical success factors in order to explore the possible propagation of critical success factors within a project system network and its implications on project success.

Abstract Objective To conduct a comprehensive mapping of published indicators for monitoring and evaluation (M&E) of sexual and reproductive health (SRH) services and outcomes in humanitarian settings. Methods A systematic search of the peer-reviewed and grey literature published between January 2008 and May 2018 was conducted to identify all references describing indicator sets for M&E of SRH services and outcomes in humanitarian settings. The databases MEDLINE, Web of Science, and Global Health, as well as 85 websites of relevant organizations involved in humanitarian response were searched. Characteristics of identified indicator sets and data from individual indicators was extracted. Findings Of 3278 records identified, 20 met the review’s inclusion criteria and 9 existing indicator sets were identified. A total of 179 relevant indicators were included in the mapping, and removal of duplicates yielded 132 unique indicators. Twenty-seven percent fell within the maternal health domain, followed by the HIV/AIDS domain (26%) and the gender-based violence domain (23%). The distribution of indicators by type (process/output, outcome, impact) was balanced overall but varied substantially across domains. The most commonly used data collection platforms were facility-based systems or population-based surveys. Domains covered and indicator definitions were inconsistent across indicator sets. Conclusion Results demonstrate the need to standardize data collection efforts for M&E of SRH services and outcomes in humanitarian settings and to critically appraise the extent to which different domains should be covered. A core list of indicators is essential for assessing response status over time as well as across countries.

Abstract Objective Our immediate objective is to determine whether infectivity of lytic podophage T3 has a relatively high persistence in the blood of a mouse, as suggested by previous data. Secondarily, we determine whether the T3 surface has changed during this mouse passage. The surface is characterized by native agarose gel electrophoresis (AGE). Beyond our current data, the long-term objective is optimization of phages chosen for therapy of all bacteremias and associated sepsis. Results We find that the persistence of T3 in mouse blood is higher by over an order of magnitude than the previously reported persistence of (1) lysogenic phages lambda and P22, and (2) lytic phage T7, a T3 relative. We explain these differences via the lysogenic character of lambda and P22, and the physical properties of T7. For the future, we propose testing a new, AGE-based strategy for rapidly screening for high-persistence, lytic, environmental podophages that have phage therapy-promoting physical properties.

Shoulder arthroscopy has evolved significantly since its inception, with advancements in technology, surgical techniques, and patient demand driving its progress. Surgeons and scientific societies have played a crucial role in promoting and disseminating knowledge on arthroscopic shoulder surgery. Despite barriers such as surgeon apprehension, medical hyperspecialization, and the need for evidence-based medicine, substantial achievements have been made, including stable fixation systems, treatment of fractures, and performing procedures outside the glenohumeral joint. To continue innovating, the field must increase scientific knowledge, adopt digital technologies, explore navigation techniques and robotic surgery, and harness the potential of artificial intelligence and machine learning. Collaboration with industry, healthcare systems, and patients is essential for efficient and sustainable implementation of these advancements. [Extracted from the article]

The proteasome inhibitor bortezomib has shown remarkable clinical success in the treatment of multiple myeloma. However, the efficacy and mechanism of action of bortezomib in solid tumor malignancies is less well understood. In addition, the use of this first-in-class proteasome inhibitor is limited by several factors, including off-target effects that lead to adverse toxicities. We recently reported the impact and mechanisms of carfilzomib and oprozomib, second-in-class proteasome inhibitors with higher specificities and reduced toxicities, against head and neck squamous cell carcinoma (HNSCC). Carfilzomib and oprozomib potently inhibit HNSCC cell survival and the growth of HNSCC tumors. Both compounds promote upregulation of proapoptotic BIK and antiapoptotic MCL1, which serves to mediate and attenuate, respectively, the killing activities of these proteasome inhibitors. Both compounds also induce complete autophagic flux that is partially dependent on activation of the unfolded protein response (UPR) and upregulation of ATF4. Carfilzomib- and oprozomib-induced autophagy acts to promote HNSCC cell survival. Our study indicates that the therapeutic benefit of these promising proteasome inhibitors may be improved by inhibiting MCL1 expression or autophagy.

PurposeCarfilzomib is a selective, irreversible inhibitor of the chymotrypsin-like activity of the proteasome and is undergoing clinical evaluation in myeloma. ONX 0912 (oprozomib) is an orally bioavailable derivative. The activities of carfilzomib and ONX 0912 against solid tumor malignancies are less well understood. We investigated the impact and mechanisms of action of carfilzomib and ONX 0912 in preclinical models of head and neck squamous cell carcinoma (HNSCC).Experimental designThe effects of carfilzomib and ONX 0912 on HNSCC cell survival and xenograft tumor growth were evaluated. The impact and mechanisms of both agents on apoptosis and autophagy induction were also investigated. The contribution of the unfolded protein response (UPR) to autophagy induction and the role of autophagy in attenuating HNSCC cell death were determined.ResultsCarfilzomib and ONX 0912 potently induced apoptosis in HNSCC cell lines via upregulation of pro-apoptotic Bik. Upregulation of Mcl-1 by these agents served to dampen their efficacies. Carfilzomib and ONX 0912 also induced autophagy, mediated, in part, by activation of the UPR pathway involving upregulation of ATF4 transcription factor. Autophagy induction served a prosurvival role. Oral administration of ONX 0912 inhibited the growth of HNSCC xenograft tumors in a dose-dependent manner.ConclusionsThese results show that carfilzomib and ONX 0912 are potently active against HNSCC cells, and the activities of these agents can be enhanced via suppression of Mcl-1 or inhibition of autophagy. Oral ONX 0912 exhibits in vivo activity against HNSCC tumors and may represent a useful therapeutic agent for this malignancy.

La Estadística se ha convertido en la escencia del método científico. Surge así, la necesidad de introducirla como asignatura en todos los espacios curriculares de carreras universitarias, independientemente de su orientación. En la cual, uno de los temas ampliamente aplicados es "Test de Hipótesis", herramienta poco comprendida. Considerándose algunos posibles obstáculos en el aprendizaje del concepto, se plantea: La intensificación de la enseñanza de los conceptos Población y Muestra y de las nociones derivadas de ellos: Parámetros y Estimadores para un aprendizaje significativo del tema Test de Hipótesis Estadístico. Se trabajó con dos cohortes de alumnos de un Profesorado en Biología. La cohorte 2005 conformó la muestra "Control" y la cohorte 2006 la muestra "Experimental". Al "Control" se le dió Bioestadística según la metodología y planificación tradicional, al "Experimental" se efectuaron modificaciones en la planificación, contenidos y profundidad. La metodología incluyó la resolución de problemas reales, simulaciones y ejercicios aplicados diseñados bajo ciertos criterios pedagógicos. Se observó que la proporción de alumnos, que evidenció mejor comprensión de los conceptos involucrados en los Test de Hipótesis, fue estadísticamente mayor en el grupo Experimental. Por lo que podría aceptarse que las estrategias didácticas incorporadas influyen positivamente en el aprendizaje significativo del tema.

Abstract Objective Our immediate objective is to test the data-suggested possibility that in-agarose gel bacterial propagation causes gel fiber dislocation and alteration of cell distribution. We also test the further effect of lowering water activity. We perform these tests with both Gram-negative and Gram-positive bacteria. Data are obtained via electron microscopy of thin sections, which provides the first images of both bacteria and gel fibers in gel-supported bacterial lawns. The long-term objective is analysis of the effects of in-gel propagation on the DNA packaging of phages. Results We find that agarose gel-supported cells in lawns of Escherichia coli and Lysinibacillus (1) are primarily in clusters that increase in size with time and are surrounded by gel fibers, and (2) sometimes undergo gel-induced, post-duplication rotation and translation. Bacterial growth-induced dislocation of gel fibers is observed. One reason for clustering is that clustering promotes growth by increasing the growth-derived force applied to the gel fibers. Reactive force exerted by gel on cells explains cell movement. Finally, addition to growth medium of 0.94 M sucrose causes cluster-associated E. coli cells to become more densely packed and polymorphic. Shape is determined, in part, by neighboring cells, a novel observation to our knowledge.

Phage G is recognized as having a remarkably large genome and capsid size among isolated, propagated phages. Negative stain electron microscopy of the host–phage G interaction reveals tail sheaths that are contracted towards the distal tip and decoupled from the head–neck region. This is different from the typical myophage tail contraction, where the sheath contracts upward, while being linked to the head–neck region. Our cryo-EM structures of the non-contracted and contracted tail sheath show that: (1) The protein fold of the sheath protein is very similar to its counterpart in smaller, contractile phages such as T4 and phi812; (2) Phage G’s sheath structure in the non-contracted and contracted states are similar to phage T4’s sheath structure. Similarity to other myophages is confirmed by a comparison-based study of the tail sheath’s helical symmetry, the sheath protein’s evolutionary timetree, and the organization of genes involved in tail morphogenesis. Atypical phase G tail contraction could be due to a missing anchor point at the upper end of the tail sheath that allows the decoupling of the sheath from the head–neck region. Explaining the atypical tail contraction requires further investigation of the phage G sheath anchor points.

The following hypothesis proposes non-diffusive, environmental bacteriophage (phage) motion. (1) Some phage-hosting, motile bacteria undergo chemotaxis down ATP concentration gradients to escape lysis-inducing conditions, such as phage infection. (2) Some phages respond by non-infective binding to the motile bacteria. (3) When the bacteria reach a lower ATP concentration, which is a condition that signals increased density of phage-susceptible bacteria, the phage converts, Trojan-horse-like, to productive binding and infection. This hypothesis was previously proposed for Bacillus thuringiensis siphophage 0105phi7-2. It is tested here and confirmed with the following observations. (1) B. thuringiensis is found, macroscopically, preferentially located at low ATP concentrations when propagated in-gel after inoculation in the center of an artificially generated ATP concentration gradient. (2) Inoculating phage 0105phi7-2 at the bacteria inoculation site, 2–3 h after inoculation of bacteria, results in cell lysing activity that moves with the bacteria, without a visible trail of lysis. Trojan-horse-like behavior is consistent with only biofilm-inhabiting phages because environmental selection for this behavior requires limited fluid flows. We propose using artificial ATP concentration gradients to instigate Trojan-horse-like phage behavior during phage therapy of bacterial biofilms. [ABSTRACT FROM AUTHOR]

Phage characterization for research and therapy can involve newly isolated phages propagated in pathogenic bacteria. If so, characterization requires safety-managing the bacteria. In the current study, we adapt a common and inexpensive reagent, PrimeStore (Longhorn Vaccines and Diagnostics, San Antonio, TX, USA), to safety-manage bacteria in 20 min by selectively inactivating the bacteria. No bacterial survivors are observed among >109 bacteria per ml for a representative of both Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Bacillus thuringiensis). This procedure causes no detected inactivation of podophage T3, myophage T4 and siphophage 0105phi7-2. Margins of safety for PrimeStore concentration exist for bacterial inactivation and phage non-inactivation. Thus, general applicability is expected. Subsequent dialysis is used to block long-term effects on phages. Nonetheless, comparable tests should be performed for each pathogenic bacterial strain/phage. Electron microscopy of thin sections reveals inactivation-altered bacterial cytoplasm and a non-disintegrated bacterial envelope (ghosts). Ghosting of E. coli includes re-arrangement of the cytoplasm and the release of endotoxin. The activity of the released endotoxin is >99% reduced after subsequent dialysis, which also removes PrimeStore components. Ghosting of B. thuringiensis includes apparent phase separation within the cytoplasm. The primary application envisaged is biophysical and other screening of phages for therapy of infectious disease. [ABSTRACT FROM AUTHOR]

Blood-borne therapeutic phages and phage capsids increasingly reach therapeutic targets as they acquire more persistence, i.e., become more resistant to non-targeted removal from blood. Pathogenic bacteria are targets during classical phage therapy. Metastatic tumors are potential future targets, during use of drug delivery vehicles (DDVs) that are phage derived. Phage therapy has, to date, only sometimes been successful. One cause of failure is low phage persistence. A three-step strategy for increasing persistence is to increase (1) the speed of lytic phage isolation, (2) the diversity of phages isolated, and (3) the effectiveness and speed of screening phages for high persistence. The importance of high persistence-screening is illustrated by our finding here of persistence dramatically higher for coliphage T3 than for its relative, coliphage T7, in murine blood. Coliphage T4 is more persistent, long-term than T3. Pseudomonas chlororaphis phage 201phi2-1 has relatively low persistence. These data are obtained with phages co-inoculated and separately assayed. In addition, highly persistent phage T3 undergoes dispersal to several murine organs and displays tumor tropism in epithelial tissue (xenografted human oral squamous cell carcinoma). Dispersal is an asset for phage therapy, but a liability for phage-based DDVs. We propose increased focus on phage persistence—and dispersal—screening.

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