The fliR gene contributes to the virulence of S. marcescens in a Drosophila intestinal infection model

Abstract Serratia marcescens is an opportunistic bacterium that infects a wide range of hosts including humans. It is a potent pathogen in a septic injury model of Drosophila melanogaster as five bacteria directly injected in the body cavity of the fly kill the host within a day. In contrast, flies do not succumb to ingested bacteria for days even though some bacteria traverse the intestinal barrier into the hemolymph within a couple of hours. The mechanisms by which S. marcescens attacks enterocytes and damages the intestinal epithelium remain uncharacterized. To better understand intestinal infections, we performed a genetic screen for loss of virulence of ingested S. marcescens in which we identified FliR, a structural component of the flagellum, as a virulence factor. Next, we compared the virulence of two flagellum mutants fliR and flhD using two Serratia strains. Both genes are required for S. marcescens to escape the gut lumen into the hemocoel indicating that the flagellum plays an important role for the passage of bacteria through the intestinal barrier. In contrast, fliR but not flhD is needed to severely damage the intestinal epithelium and ultimately kill the host. Our results therefore suggest a flagellum-independent role for fliR in bacterial virulence.

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RhlR, but not RhlI, allowsP. aeruginosabacteria to evadeDrosophilaTep4-mediated opsonization

10.1101/165530 ◽

2017 ◽

Author(s):

Samantha Haller ◽

Adrien Franchet ◽

Abdul Hakkim ◽

Jing Chen ◽

Eliana Drenkard ◽

...

Keyword(s):

Intestinal Barrier ◽

Infection Model ◽

Dependent Manner ◽

Intestinal Infection ◽

Wild Type ◽

Independent Function ◽

C Elegans ◽

Injury Model ◽

Mutant Phenotypes ◽

Cellular Immune

ABSTRACTWhenDrosophilaflies feed onPseudomonas aeruginosastrain PA14, some bacteria cross the intestinal barrier and start proliferating inside the hemocoel. This process is limited by hemocytes through phagocytosis. We have previously shown that the PA14 quorum-sensing regulator RhlR is required for these bacteria to elude the cellular immune response. RhlI synthesizes the auto-inducer signal that activates RhlR. Here, we compare the null mutant phenotypes ofrhlRandrhlIin a variety of infection assays inDrosophilaand in the nematodeCaenorhabditis elegans. Surprisingly, inDrosophila, unlikeΔrhlRmutants,ΔrhlImutants are only modestly attenuated for virulence and are poorly phagocytosed and opsonized in a Thioester-containing Protein4-dependent manner. Likewise, ΔrhlIbut not ΔrhlRmutants colonize the digestive tract ofC. elegansand kill it as efficiently as wild-type PA14. Thus, RhlR has an RhlI-independent function in eluding detection or counter-acting the action of the immune system. In contrast to the intestinal infection model,Tep4mutant flies are more resistant to PA14 in a septic injury model, which also depends onrhlR. Thus, the Tep4 putative opsonin can either be protective or detrimental to host defense depending on the infection route.

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Morphological analysis and description of the ovaries of female silky sharks, Carcharhinus falciformis (Müller & Henle, 1839)

Neotropical Ichthyology ◽

10.1590/s1679-62252013000400009 ◽

2013 ◽

Vol 11 (4) ◽

pp. 815-819 ◽

Cited By ~ 2

Author(s):

Mariana G. Rêgo ◽

Fábio H. V. Hazin ◽

Joaquim Evêncio Neto ◽

P. G. V. Oliveira ◽

Maria Goretti Soares ◽

...

Keyword(s):

Reproductive Tract ◽

Body Cavity ◽

Female Reproductive Tract ◽

The Body ◽

Epithelial Tissue ◽

Equatorial Atlantic ◽

Anterior Section ◽

Simple Cubic ◽

Wide Range ◽

Carcharhinus Falciformis

This work aims to study the female reproductive tract of silky sharks, Carcharhinus falciformis, captured in the South and Equatorial Atlantic Ocean. Samples were collected between January 2008 and March 2010 through oceanic commercial vessels that targeted tuna and swordfish, with a total of 17 females collected. The methodologies followed for analyzing the ovaries of those females included both macroscopic and histological analysis. Macroscopically, it was possible to determine that the ovaries on these sharks is suspended by mesenteries in the anterior section of the body cavity, heavily irrigated by blood vessels, and contains a wide range of oocytes. Ovaries were found in three distinct maturational stages: Stage I (Immature), Stage II (Maturing) and Stage III (Mature). Immature ovaries were small, with widths ranging from 1.0 to 3.1 cm, and had a gelatinous or granulose internal structure; maturing ovaries were slightly larger, ranging in width between 5.2 and 6.0 cm; mature ovaries ranged in width between 6.5 and 7.8 cm, and had a more rounded shape and the presence of large and well developed oocytes. Under microscopic examination, it was observed that the ovaries were covered with simple epithelial tissue during the early development stages and a simple cubic epithelium in the final stages of maturation. During the initial maturation stages the epigonal organ was not differentiated from the ovary. In mature specimens, the ovary showed a simple cubic epithelium and just below this epithelium there was a layer of dense connective tissue and muscle with the presence of vitellogenic oocytes and fat cells. A thin yolk membrane enclosing the oocytes was also evident. Finally, it was possible to distinguish a zona pellucida, separating the oocytes from the follicle wall and a basal lamina between the granular layers and the teak layer.

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When Insult Is Added to Injury: Cross Talk between ILCs and Intestinal Epithelium in IBD

Mediators of Inflammation ◽

10.1155/2016/9765238 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11 ◽

Cited By ~ 9

Author(s):

Esmé van der Gracht ◽

Sonja Zahner ◽

Mitchell Kronenberg

Keyword(s):

Intestinal Epithelium ◽

Immune Cells ◽

Intestinal Barrier ◽

Biochemical Properties ◽

The Body ◽

Lymphoid Cells ◽

Intestinal Lumen ◽

Epithelial Barrier ◽

Epithelial Barrier Function ◽

Critical Feedback

Inflammatory bowel disease (IBD) is characterized by an impairment of the integrity of the mucosal epithelial barrier, which causes exacerbated inflammation of the intestine. The intestinal barrier is formed by different specialized epithelial cells, which separate the intestinal lumen from the lamina propria. In addition to its crucial role in protecting the body from invading pathogens, the intestinal epithelium contributes to intestinal homeostasis by its biochemical properties and communication to underlying immune cells. Innate lymphoid cells (ILCs) are a recently described population of lymphocytes that have been implicated in both mucosal homeostasis and inflammation. Recent findings indicate a critical feedback loop in which damaged epithelium activates these innate immune cells to restore epithelial barrier function. This review will focus on the signalling pathways between damaged epithelium and ILCs involved in repair of the epithelial barrier and tissue homeostasis and the relationship of these processes with the control of IBD.

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Creating the Wind

Latin American and Latinx Visual Culture ◽

10.1525/lavc.2020.2.4.14 ◽

2020 ◽

Vol 2 (4) ◽

pp. 14-31

Author(s):

Élodie Dupey García

Keyword(s):

Indigenous Communities ◽

The Body ◽

Historical Sources ◽

Natural Behavior ◽

Sensory Experiences ◽

Identity And Agency ◽

Wide Range ◽

Late Postclassic ◽

Comparative Examination ◽

Meteorological Phenomenon

This article explores how the Nahua of late Postclassic Mesoamerica (1200–1521 CE) created living and material embodiments of their wind god constructed on the basis of sensory experiences that shaped their conception of this divinized meteorological phenomenon. In this process, they employed chromatic and design devices, based on a wide range of natural elements, to add several layers of meaning to the human, painted, and sculpted supports dressed in the god’s insignia. Through a comparative examination of pre-Columbian visual production—especially codices and sculptures—historical sources mainly written in Nahuatl during the viceregal period, and ethnographic data on indigenous communities in modern Mexico, my analysis targets the body paint and shell jewelry of the anthropomorphic “images” of the wind god, along with the Feathered Serpent and the monkey-inspired embodiments of the deity. This study identifies the centrality of other human senses beyond sight in the conception of the wind god and the making of its earthly manifestations. Constructing these deity “images” was tantamount to creating the wind because they were intended to be visual replicas of the wind’s natural behavior. At the same time, they referred to the identity and agency of the wind god in myths and rituals.

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Development and Validation of a New Scoring Tool to Evaluate the Clinical Evolution of Adult Patients with Nonsegmental Vitiligo

Dermatology ◽

10.1159/000511890 ◽

2021 ◽

pp. 1-9

Author(s):

María Luisa Peralta-Pedrero ◽

Denisse Herrera-Bringas ◽

Karla Samantha Torres-González ◽

Martha Alejandra Morales-Sánchez ◽

Fermín Jurado Santa-Cruz ◽

...

Keyword(s):

Body Surface ◽

Task Force ◽

Intraclass Correlation ◽

The Body ◽

Response To Treatment ◽

Similar Response ◽

Clinical Evolution ◽

Wide Range ◽

Patient Reported ◽

Extreme Groups

Background: Vitiligo has an unpredictable course and a variable response to treatment. Furthermore, the improvement of some vitiligo lesions cannot be considered a guarantee of a similar response to the other lesions. Instruments for patient-reported outcome measures (PROM) can be an alternative to measure complex constructions such as clinical evolution. Objective: The aim of this study was to validate a PROM that allows to measure the clinical evolution of patients with nonsegmental vitiligo in a simple but standardized way that serves to gather information for a better understanding of the disease. Methods: The instrument was created through expert consensus and patient participation. For the validation study, a prospective cohort design was performed. The body surface area affected was measured with the Vitiligo Extension Score (VES), the extension, the stage, and the spread by the evaluation of the Vitiligo European Task Force assessment (VETFa). Reliability was determined with test-retest, construct validity through hypothesis testing, discriminative capacity with extreme groups, and response capacity by comparing initial and final measurements. Results: Eighteen semi-structured interviews and 7 cognitive interviews were conducted, and 4 dermatologists were consulted. The instrument Clinical Evolution-Vitiligo (CV-6) was answered by 119 patients with a minimum of primary schooling. A wide range was observed in the affected body surface; incident and prevalent cases were included. The average time to answer the CV-6 was 3.08 ± 0.58 min. In the test-retest (n = 53), an intraclass correlation coefficient was obtained: 0.896 (95% CI 0.82–0.94; p < 0.001). In extreme groups, the mean score was 2 (2–3) and 5 (4–6); p < 0.001. The initial CV-6 score was different from the final one and the change was verified with VES and VETFa (p < 0.05, n = 92). Conclusions: The CV-6 instrument allows patient collaboration, it is simple and brief, and it makes it easier for the doctor to focus attention on injuries that present changes at the time of medical consultation.

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Hydromechanics of low-Reynolds-number flow. Part 2. Singularity method for Stokes flows

Journal of Fluid Mechanics ◽

10.1017/s0022112075000614 ◽

1975 ◽

Vol 67 (4) ◽

pp. 787-815 ◽

Cited By ~ 300

Author(s):

Allen T. Chwang ◽

T. Yao-Tsu Wu

Keyword(s):

Exact Solutions ◽

Stokes Flow ◽

Fundamental Solutions ◽

The Body ◽

Circular Cylinders ◽

Geometrical Parameters ◽

Flow Problems ◽

Singularity Method ◽

Wide Range ◽

Body Shapes

The present study further explores the fundamental singular solutions for Stokes flow that can be useful for constructing solutions over a wide range of free-stream profiles and body shapes. The primary singularity is the Stokeslet, which is associated with a singular point force embedded in a Stokes flow. From its derivatives other fundamental singularities can be obtained, including rotlets, stresslets, potential doublets and higher-order poles derived from them. For treating interior Stokes-flow problems new fundamental solutions are introduced; they include the Stokeson and its derivatives, called the roton and stresson.These fundamental singularities are employed here to construct exact solutions to a number of exterior and interior Stokes-flow problems for several specific body shapes translating and rotating in a viscous fluid which may itself be providing a primary flow. The different primary flows considered here include the uniform stream, shear flows, parabolic profiles and extensional flows (hyper-bolic profiles), while the body shapes cover prolate spheroids, spheres and circular cylinders. The salient features of these exact solutions (all obtained in closed form) regarding the types of singularities required for the construction of a solution in each specific case, their distribution densities and the range of validity of the solution, which may depend on the characteristic Reynolds numbers and governing geometrical parameters, are discussed.

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A Computational Study on the Role of Parameters for Identification of Thyroid Nodules by Infrared Images (and Comparison with Real Data)

Sensors ◽

10.3390/s21134459 ◽

2021 ◽

Vol 21 (13) ◽

pp. 4459

Author(s):

José R. González ◽

Charbel Damião ◽

Maira Moran ◽

Cristina A. Pantaleão ◽

Rubens A. Cruz ◽

...

Keyword(s):

Heat Transfer ◽

Thyroid Nodules ◽

Numerical Study ◽

Computational Study ◽

Internal Heat ◽

Heat Transfer Process ◽

The Body ◽

Physical Parameters ◽

Infrared Sensors ◽

Wide Range

According to experts and medical literature, healthy thyroids and thyroids containing benign nodules tend to be less inflamed and less active than those with malignant nodules. It seems to be a consensus that malignant nodules have more blood veins and more blood circulation. This may be related to the maintenance of the nodule’s heat at a higher level compared with neighboring tissues. If the internal heat modifies the skin radiation, then it could be detected by infrared sensors. The goal of this work is the investigation of the factors that allow this detection, and the possible relation with any pattern referent to nodule malignancy. We aim to consider a wide range of factors, so a great number of numerical simulations of the heat transfer in the region under analysis, based on the Finite Element method, are performed to study the influence of each nodule and patient characteristics on the infrared sensor acquisition. To do so, the protocol for infrared thyroid examination used in our university’s hospital is simulated in the numerical study. This protocol presents two phases. In the first one, the body under observation is in steady state. In the second one, it is submitted to thermal stress (transient state). Both are simulated in order to verify if it is possible (by infrared sensors) to identify different behavior referent to malignant nodules. Moreover, when the simulation indicates possible important aspects, patients with and without similar characteristics are examined to confirm such influences. The results show that the tissues between skin and thyroid, as well as the nodule size, have an influence on superficial temperatures. Other thermal parameters of thyroid nodules show little influence on surface infrared emissions, for instance, those related to the vascularization of the nodule. All details of the physical parameters used in the simulations, characteristics of the real nodules and thermal examinations are publicly available, allowing these simulations to be compared with other types of heat transfer solutions and infrared examination protocols. Among the main contributions of this work, we highlight the simulation of the possible range of parameters, and definition of the simulation approach for mapping the used infrared protocol, promoting the investigation of a possible relation between the heat transfer process and the data obtained by infrared acquisitions.

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Polymer-Drug Conjugates as Nanotheranostic Agents

Journal of Nanotheranostics ◽

10.3390/jnt2010005 ◽

2021 ◽

Vol 2 (1) ◽

pp. 63-81

Author(s):

Sajana Manandhar ◽

Erica Sjöholm ◽

Johan Bobacka ◽

Jessica M. Rosenholm ◽

Kuldeep K. Bansal

Keyword(s):

Drug Delivery ◽

Drug Release ◽

Treatment Options ◽

The Body ◽

Drug Conjugates ◽

Imaging Characteristics ◽

Wide Range ◽

Systemic Side Effects ◽

Theranostic Agents ◽

The Stability

Since the last decade, the polymer-drug conjugate (PDC) approach has emerged as one of the most promising drug-delivery technologies owing to several benefits like circumventing premature drug release, offering controlled and targeted drug delivery, improving the stability, safety, and kinetics of conjugated drugs, and so forth. In recent years, PDC technology has advanced with the objective to further enhance the treatment outcomes by integrating nanotechnology and multifunctional characteristics into these systems. One such development is the ability of PDCs to act as theranostic agents, permitting simultaneous diagnosis and treatment options. Theranostic nanocarriers offer the opportunity to track the distribution of PDCs within the body and help to localize the diseased site. This characteristic is of particular interest, especially among those therapeutic approaches where external stimuli are supposed to be applied for abrupt drug release at the target site for localized delivery to avoid systemic side effects (e.g., Visudyne®). Thus, with the help of this review article, we are presenting the most recent updates in the domain of PDCs as nanotheranostic agents. Different methodologies utilized to design PDCs along with imaging characteristics and their applicability in a wide range of diseases, have been summarized in this article.

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Sustainable Sources from Aquatic Organisms for Cosmeceuticals Ingredients

Cosmetics ◽

10.3390/cosmetics8020048 ◽

2021 ◽

Vol 8 (2) ◽

pp. 48

Author(s):

Carmen G. Sotelo ◽

María Blanco ◽

Patricia Ramos ◽

José A. Vázquez ◽

Ricardo I. Perez-Martin

Keyword(s):

Social Issues ◽

Good Condition ◽

Aquatic Organisms ◽

The Body ◽

Fishing Activity ◽

Marine Biomass ◽

Cosmetic Industry ◽

Wide Range ◽

Long Life ◽

By Products

Long life expectancy of populations in the developing world together with some cultural and social issues has driven the need to pay special attention to health and physical appearance. Cosmeceuticals are gaining interest in the cosmetic industry as their uses fulfills a double purpose: the requirements of a cosmetic (clean, perfume, protect, change the appearance of the external parts of the body or keeping them in good condition) with a particular bioactivity function. The cosmetics industry, producing both cosmetics and cosmeceuticals, is currently facing numerous challenges to satisfy different attitudes of consumers (vegetarianism, veganism, cultural or religious concerns, health or safety reasons, eco-friendly process, etc.). A currently growing trend in the market is the interest in products of low environmental impact. Marine origin ingredients are increasingly being incorporated into cosmeceutical preparations because they are able to address several consumer requirements and also due to the wide range of bioactivities they present (antioxidant, whitening, anti-aging, etc.). Many companies claim “Marine” as a distinctive marketing signal; however, only a few indicate whether they use sustainable ingredient sources. Sustainable marine ingredients might be obtained using wild marine biomass through a sustainable extractive fishing activity; by adopting valorization strategies including the use of fish discards and fish by-products; and by sustainably farming and culturing marine organisms.

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Electromechanical fields in a hollow piezoelectric cylinder under non-uniform load: flexoelectric effect

Mathematics and Mechanics of Solids ◽

10.1177/10812865211020785 ◽

2021 ◽

pp. 108128652110207

Author(s):

Olha Hrytsyna

Keyword(s):

Analytical Solutions ◽

Point Group ◽

The Body ◽

Small Scale ◽

Gradient Theory ◽

Local Mass ◽

Wide Range ◽

Mass Displacement ◽

Local Mass Displacement ◽

Local Gradient

The relations of a local gradient non-ferromagnetic electroelastic continuum are used to solve the problem of an axisymmetrical loaded hollow cylinder. Analytical solutions are obtained for tetragonal piezoelectric materials of point group 4 mm for two cases of external loads applied to the body surfaces. Namely, the hollow pressurized cylinder and a cylinder subjected to an electrical voltage V across its thickness are considered. The derived solutions demonstrate that the non-uniform electric load causes a mechanical deformation of piezoelectric body, and vice versa, the inhomogeneous radial pressure of the cylinder induces its polarization. Such a result is obtained due to coupling between the electromechanical fields and a local mass displacement being considered. In the local gradient theory, the local mass displacement is associated with the changes to a material’s microstructure. The classical theory does not consider the effect of material microstructure on the behavior of solid bodies and is incapable of explaining the mentioned phenomena. It is also shown that the local gradient theory describes the size-dependent properties of piezoelectric nanocylinders. Analytical solutions to the formulated boundary-value problems can be used in conjunction with experimental data to estimate some higher-order material constants of the local gradient piezoelectricity. The obtained results may be useful for a wide range of appliances that utilize small-scale piezoelectric elements as constituting blocks.

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