The presence of professional phagocytes dictates the number of host cells targeted for Yop translocation during infection.

Type III secretion systems deliver effector proteins from Gram-negative bacterial pathogens into host cells, where they disarm host defences, allowing the pathogens to establish infection. Although Yersinia pseudotuberculosis delivers its effector proteins, called Yops, into numerous cell types grown in culture, we show that during infection Y. pseudotuberculosis selectively targets Yops to professional phagocytes in Peyer's patches, mesenteric lymph nodes and spleen, although it colocalizes with B and T cells as well as professional phagocytes. Strikingly, in the absence of neutrophils, the number of cells with translocated Yops was significantly reduced although the bacterial loads were similar, indicating that Y. pseudotuberculosis did not arbitrarily deliver Yops to the available cells. Using isolated splenocytes, selective binding and selective targeting to professional phagocytes when bacteria were limiting was also observed, indicating that tissue architecture was not required for the tropism for professional phagocytes. In isolated splenocytes, YadA and Invasin increased the number of all cells types with translocated Yops, but professional phagocytes were still preferentially translocated with Yops in the absence of these adhesins. Together these results indicate that Y. pseudotuberculosis discriminates among cells it encounters during infection and selectively delivers Yops to phagocytes while refraining from translocation to other cell types.

Population Management Approach to Kidney Stone Care Improves Patient Compliance to Preventive Measures and Reduces Resource Utilization in Patients at High Risk for Stone Recurrence.

INTRODUCTION: Nephrolithiasis is a chronic condition with 5 to 10-year recurrence rates as high as 50%. Stone recurrence can be reduced by implementing American Urological Association kidney stone medical management guidelines, which recommend additional metabolic testing for high risk, recurrent and interested first-time stone formers. However, clinician adherence to guidelines is variable, and patient compliance with preventive evaluations is low. We evaluated our kidney stone population management program's role in patient compliance with completing American Urological Association metabolic studies. We assessed the program's impact on office encounters, operating room procedures and emergency department visits for known high risk kidney stone patients. METHODS: A retrospective review of electronic medical records between 2009 and 2017 identified 4,029 kidney stone patients. A total of 873 patients were at high risk for kidney stone recurrence. In 2013, we established a population management program in which high risk patients were referred and followed by a nurse case manager. Patients were contacted by email or telephone if metabolic serum and urine collections were incomplete. Office, operating room and emergency department visits were compared before and after the program's implementation. RESULTS: Metabolic evaluation orders increased from 17% to 35% in our institution's urology department. Patient compliance with recommended studies improved from <10% to 82%, and reductions in office visits by 48%, surgical procedures by 38% and emergency department encounters by 40% were observed. CONCLUSIONS: Our program improved patient compliance with American Urological Association recommended studies for high risk kidney stone patients. Reductions in stone events may have been due to our program but require further study in the future.

Small molecule inhibitors of LcrF, a Yersinia pseudotuberculosis transcription factor, attenuate virulence and limit infection in a murine pneumonia model.

LcrF (VirF), a transcription factor in the multiple adaptational response (MAR) family, regulates expression of the Yersinia type III secretion system (T3SS). Yersinia pseudotuberculosis lcrF-null mutants showed attenuated virulence in tissue culture and animal models of infection. Targeting of LcrF offers a novel, antivirulence strategy for preventing Yersinia infection. A small molecule library was screened for inhibition of LcrF-DNA binding in an in vitro assay. All of the compounds lacked intrinsic antibacterial activity and did not demonstrate toxicity against mammalian cells. A subset of these compounds inhibited T3SS-dependent cytotoxicity of Y. pseudotuberculosis toward macrophages in vitro. In a murine model of Y. pseudotuberculosis pneumonia, two compounds significantly reduced the bacterial burden in the lungs and afforded a dramatic survival advantage. The MAR family of transcription factors is well conserved, with members playing central roles in pathogenesis across bacterial genera; thus, the inhibitors could have broad applicability.

Identification and characterization of small-molecule inhibitors of Yop translocation in Yersinia pseudotuberculosis.

Type three secretion systems (TTSSs) are virulence factors found in many pathogenic Gram-negative species, including the family of pathogenic Yersinia spp. Yersinia pseudotuberculosis requires the translocation of a group of effector molecules, called Yops, to subvert the innate immune response and establish infection. Polarized transfer of Yops from bacteria to immune cells depends on several factors, including the presence of a functional TTSS, the successful attachment of Yersinia to the target cell, and translocon insertion into the target cell membrane. Here we employed a high-throughput screen to identify small molecules that block translocation of Yops into mammalian cells. We identified 6 compounds that inhibited translocation of effectors without affecting synthesis of TTSS components and secreted effectors, assembly of the TTSS, or secretion of effectors. One compound, C20, reduced adherence of Y. pseudotuberculosis to target cells. Additionally, the compounds caused leakage of Yops into the supernatant during infection and thus reduced polarized translocation. Furthermore, several molecules, namely, C20, C22, C24, C34, and C38, also inhibited ExoS-mediated cell rounding, suggesting that the compounds target factors that are conserved between Pseudomonas aeruginosa and Y. pseudotuberculosis. In summary, we have identified 6 compounds that specifically inhibit translocation of Yops into mammalian cells but not Yop synthesis or secretion.

Clathrin-dependent pathways and the cytoskeleton network are involved in ceramide endocytosis by a parasitic protozoan, Giardia lamblia.

Although identified as an early-diverged protozoan, Giardia lamblia shares many similarities with higher eukaryotic cells, including an internal membrane system and cytoskeleton, as well as secretory pathways. However, unlike many other eukaryotes, Giardia does not synthesize lipids de novo, but rather depends on exogenous sources for both energy production and organelle or membrane biogenesis. It is not known how lipid molecules are taken up by this parasite and if endocytic pathways are involved in this process. In this investigation, we tested the hypothesis that highly regulated and selective lipid transport machinery is present in Giardia and necessary for the efficient internalization and intracellular targeting of ceramide molecules, the major sphingolipid precursor. Using metabolic and pathway inhibitors, we demonstrate that ceramide is internalized through endocytic pathways and is primarily targeted into perinuclear/endoplasmic reticulum membranes. Further investigations suggested that Giardia uses both clathrin-dependent pathways and the actin cytoskeleton for ceramide uptake, as well as microtubule filaments for intracellular localization and targeting. We speculate that this parasitic protozoan has evolved cytoskeletal and clathrin-dependent endocytic mechanisms for importing ceramide molecules from the cell exterior for the synthesis of membranes and vesicles during growth and differentiation.

Revisión bibliográfica de la ayahuasca y su uso terapéutico / Bibliographic review of ayahuasca and its therapeutic use

La ayahuasca es un brebaje psicotrópico con acción serotoninérgica. Las fuentes botánicas más comunes de la ayahuasca son la Banisteriopsiscaapi y la Psychotriaviridis, en la revisión bibliográfica se buscó conocer las propiedades bioquímicas, síntomas y signos que produce esta planta, asimismo, se reconocieron los efectos que produce al ser utilizada como brebaje por los chamanes de la Amazonía y su uso como medicamento homeopático. Con esta investigación se puede comparar, afirmar o negar las indicaciones empíricas que manejan los chamanes de nuestra región frente a los diferentes estudios científicos realizados por médicos, antropólogos y psicólogos y, de este modo dilucidar la utilidad de la planta en el campo de la homeopatía. Según Fericgla, JM, la ayahuasca es útil para inducir estados emocionales y espirituales de carácter curativo, introspectivo y terapéutico. Por otro lado, no se ha observado que su consumo genere adicción psicológica ni fisiológica, por lo que se puede afirmar que no representa ningún peligro para la salud pública. Palma D, manifiesta que la Di MetilTriptamina (DMT) es la principal responsable de los efectos psicoactivos del brebaje y que actúa en el timo y la glándula pineal.

Ayahuasca is a psychotropic potion with serotonergic action. The most common botanical sources of ayahuasca are Banisteriopsis caapi and Psychotria viridis, in the Bibliographic Review it was sought to know the Biochemical properties, Symptoms and signs that Ayahuasca produces Corroborating with the effects that it produces when is used as a potion by shamans from the Amazon and being dynamically prepared as a Homeopathic medicine. With this investigation it is possible to compare affirming or denying the empirical indications that the Shamans of our region handle with the different Scientific studies carried out by doctors, anthropologists and psychologists; and see what is the utility that is given in the field of Homeopathy. According to Fericgla. Josep María states that it is useful to induce emotional and spiritual states of a healing, introspective and therapeutic nature. On the other side, it has not been observed that the consumption of Ayahuasca generates psychological or physiological addiction, so it can be stated that it does not represent any danger to Public Health. According to Diego Palma, he states that Di Methyl Tryptamine (DMT) is primarily responsible for the psychoactive effects of the brew. Acting at the Thymus and Pineal Gland level

Lipid metabolism in mucous-dwelling amitochondriate protozoa.

Entamoeba, Giardia, and trichomonads are the prominent members of a group known as 'mucosal parasites'. While Entamoeba and Giardia trophozoites colonise the small intestine, trichomonads inhabit the genitourinary tracts of humans and animals. These protozoa lack mitochondria, well-developed Golgi complexes, and other organelles typical of higher eukaryotes. Nonetheless, they have developed unique metabolic pathways that allow them to survive and multiply in the small intestine and reproductive tracts by scavenging nutrients from the host. Various investigators have shown that these protozoa are unable to synthesise the majority of their own lipids and cholesterol de novo; rather, they depend mostly on supplies from outside sources. Therefore, questions of how they transport and utilise exogenous lipids for metabolic purposes are extremely important. There is evidence suggesting that these parasites can take up the lipids and cholesterol they need from lipoprotein particles present in the host and/or in the growth medium. Studies also support the idea that individual lipid and fatty acid molecules can be transported without the help of lipoproteins. Exogenous phospholipids have been shown to undergo fatty acid remodelling (by deacylation/reacylation reactions), which allows these protozoa to alter lipids, bypassing the synthesis of entirely new phospholipid molecules. In addition, many of these amitochondriates are, however, capable of elongating/desaturating long-chain fatty acids, and assembling novel glycophospholipid molecules. In this review, progress in various aspects of lipid research on these organisms is discussed. Attempts are also made to identify steps of lipid metabolic pathways that can be used to develop chemotherapeutic agents against these and other mucosal parasites.

Intranasal inoculation of mice with Yersinia pseudotuberculosis causes a lethal lung infection that is dependent on Yersinia outer proteins and PhoP.

Yersinia pseudotuberculosis infects many mammals and birds including humans, livestock, and wild rodents and can be recovered from the lungs of infected animals. To determine the Y. pseudotuberculosis factors important for growth during lung infection, we developed an intranasal model of infection in mice. Following intranasal inoculation, we monitored both bacterial growth in lungs and dissemination to systemic tissues. Intranasal inoculation with as few as 18 CFU of Y. pseudotuberculosis caused a lethal lung infection in some mice. Over the course of 7 days, wild-type Y. pseudotuberculosis replicated to nearly 1 x 10(8) CFU/g of lung in BALB/c mice, induced histopathology in lungs consistent with pneumonia, but disseminated sporadically to other tissues. In contrast, a Delta yopB deletion strain was attenuated in this model, indicating that translocation of Yersinia outer proteins (Yops) is essential for virulence. Additionally, a Delta yopH null mutant failed to grow to wild-type levels by 4 days postintranasal inoculation, but deletions of any other single effector YOP did not attenuate lung colonization 4 days postinfection. Strains with deletions in yopH and any one of the other known effector yop genes were more attenuated that the Delta yopH strain, indicating a unique role for yopH in lungs. In summary, we have characterized the progression of a lung infection with an enteric Yersinia pathogen and shown that YopB and YopH are important in lung colonization and dissemination. Furthermore, this lung infection model with Y. pseudotuberculosis can be used to test potential therapeutics against Yersinia and other gram-negative infections in lungs.