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Invading microbes face a myriad of cidal mechanisms of phagocytes that inflict physical damage to microbial structures. How intracellular bacterial pathogens adapt to these stresses is not fully understood. Here, we report the discovery of a virulence mechanism by which changes to the mechanical stiffness of the mycobacterial cell surface confer refraction to killing during infection. Long-term time-lapse atomic force microscopy was used to reveal a process of "mechanical morphotype switching" in mycobacteria exposed to host intracellular stress. A "soft" mechanical morphotype switch enhances tolerance to intracellular macrophage stress, including cathelicidin. Both pharmacologic treatment, with bedaquiline, and a genetic mutant lacking uvrA modified the basal mechanical state of mycobacteria into a soft mechanical morphotype, enhancing survival in macrophages. Our study proposes microbial cell mechanical adaptation as a critical axis for surviving host-mediated stressors.

BackgroundPatients with Parkinson’s disease (PD) experience visual hallucinations, which may be related to decreased contrast sensitivity (ie, the ability to discern shades of grey). ObjectiveThe objective of this study was to investigate if an online research platform can be used to survey patients with Parkinson’s disease regarding visual hallucinations, and also be used to assess visual contrast perception. MethodsFrom the online patient community, PatientsLikeMe, 964 members were invited via email to participate in this study. Participants completed a modified version of the University of Miami Parkinson’s disease hallucinations questionnaire and an online vision test. ResultsThe study was completed by 27.9% (269/964) of those who were invited: 56.9% of this group had PD (153/269) and 43.1% (116/269) were non-Parkinson’s controls. Hallucinations were reported by 18.3% (28/153) of the Parkinson’s group. Although 10 subjects (9%) in the control group reported experiencing hallucinations, only 2 of them actually described formed hallucinations. Participants with Parkinson’s disease with a mean of 1.75 (SD 0.35) and the control group with a mean of 1.85 (SD 0.36) showed relatively good contrast perception as measured with the online letter test (P=.07). People who reported hallucinations showed contrast sensitivity levels that did not differ from levels shown by people without hallucinations (P=.96), although there was a trend towards lower contrast sensitivity in hallucinators. ConclusionsAlthough more Parkinson's responders reported visual hallucinations, a significant number of non-Parkinson's control group responders also reported visual hallucinations. The online survey method may have failed to distinguish between formed hallucinations, which are typical in Parkinson's disease, and non-formed hallucinations that have less diagnostic specificity. Multiple questions outlining the nature of the hallucinations are required. In a clinical interview, the specific nature of the hallucination would be further refined to rule out a vague description that does not indicate a true, formed visual hallucination. Contrary to previous literature, both groups showed relatively good contrast sensitivity, perhaps representing a ceiling effect or limitations of online testing conditions that are difficult to standardize. Steps can be taken in future trials to further standardize online visual function testing, to refine control group parameters and to take steps to rule out confounding variables such as comorbid disease that could be associated with hallucinations. Contacting subjects via an online health social network is a novel, cost-effective method of conducting vision research that allows large numbers of individuals to be contacted quickly, and refinement of questionnaires and visual function testing may allow more robust findings in future research.

The illegal wildlife trade (IWT) is a serious issue that threatens many species worldwide. Zoos and aquariums are in a prime position to educate visitors about this issue and work to reduce the impact of IWT. This article describes the work of four zoos across the United States that tested different ways to engage with visitors and broader communities regarding the topic of IWT. While each zoo used unique techniques to engage with the public, the authors identified common lessons learned that are relevant to all informal learning institutions interested in messaging complex topics to their audiences. The authors describe three commonalities that should be considered in the development of educational tools and messages: semantics and word choices, message framing, and the need for cultural sensitivity and respect when discussing challenging topics.

Hansen disease (leprosy) is an ancient pathology caused by 2 slow-growing intracellular bacilli, Mycobacterium leprae and M. lepromatosis (1). Both pathogens have the ability to damage peripheral nerves of hosts, [...]

Information about Kobe Bryant has focused primarily on his outstanding achievements as an NBA player (81 points, 2 gold medals, and an Academy Award). In addition, since his death, January 20, 2020, focus on his role as a father, husband, and mentor has emerged in the spotlight. Collectively, these traits provide a framework for acknowledging, understanding, and questioning this legend from theoretical lens. There are few theoretical perspectives in the literature to explain his behavior. The purpose of this article is to provide a foundation to stimulate academicians to discuss Kobe's behavior and accomplishments by applying Adler and Adler's (1989 (See CR1)) glorified self-theory. Kobe's accomplishments and challenges will be delineated utilizing Mead (1956 revised 2018) and Goffman (1959 (See CR10)) as backdrop theories with DuBois (as cited by Outlaw, 2019 (See CR19)) as the final 3-point hoop shot. Recommendations for academicians to move away from media articles in the classroom about Kobe and consider the need to encourage students to theorize utilizing classical as well as contemporary theories in their class discussions about Kobe. In this manner, the promotion of further discussion can continue in the academic arena and not only in the world of sports. As students are motivated in the academic environment, more empirical research is encouraged to provide answers to questions that many elite athletes need as they struggle with their dramaturgical self as argued by Goffman (Kivisto & Pittman, 2013 (See CR12)). It is our expectation that future research will provide elite athletes' negative pressures, and challenges a chance to rise (Bryan as cited by Chang, 2020 (See CR7))., Author(s): Kimberly R. Outlaw [sup.1] , Mary S. Jackson [sup.1] Author Affiliations: (1) grid.255364.3, 0000 0001 2191 0423, East Carolina University, , Social Work, Greenville, NC, USA The legendary professional [...]

Nine-banded armadillos (Dasypus novemcinctus) can be naturally infected with Mycobacterium leprae and have been implicated in the zoonotic transmission of leprosy in the US states of Texas, Louisiana, Alabama, Georgia, [...]

[This corrects the article DOI: 10.1371/journal.ppat.1004376.].

Mycobacterium tuberculosis employs various virulence strategies to subvert host immune responses in order to persist and cause disease. Interaction of M. tuberculosis with mannose receptor on macrophages via surface-exposed lipoarabinomannan (LAM) is believed to be critical for cell entry, inhibition of phagosome-lysosome fusion, and intracellular survival, but in vivo evidence is lacking. LprG, a cell envelope lipoprotein that is essential for virulence of M. tuberculosis, has been shown to bind to the acyl groups of lipoglycans but the role of LprG in LAM biosynthesis and localization remains unknown. Using an M. tuberculosis lprG mutant, we show that LprG is essential for normal surface expression of LAM and virulence of M. tuberculosis attributed to LAM. The lprG mutant had a normal quantity of LAM in the cell envelope, but its surface was altered and showed reduced expression of surface-exposed LAM. Functionally, the lprG mutant was defective for macrophage entry and inhibition of phagosome-lysosome fusion, was attenuated in macrophages, and was killed in the mouse lung with the onset of adaptive immunity. This study identifies the role of LprG in surface-exposed LAM expression and provides in vivo evidence for the essential role surface LAM plays in M. tuberculosis virulence. Findings have translational implications for therapy and vaccine development.

The first enterovirus D68 (EV-D68) isolate (Fermon) was identified in 1962 (1,2). Before a 2014 EV-D68 outbreak, US reports of EV-D68 were relatively sparse ( The Study We assessed the [...]