Identifying Extrinsic versus Intrinsic Drivers of Variation in Cell Behavior in Human iPSC Lines from Healthy Donors

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Urological and medical evaluation of men with erectile dysfunction

As the medical understanding of erectile dysfunction has evolved, the approach to its evaluation must also change. A good doctor/patient rapport is crucial to making patients more comfortable talking about their sexual function. Questionnaires help elicit specific information on which to base the diagnosis and find the etiology, along with examination of the genitals and hormone and other assays. If oral therapy is unsuccessful, other studies may find underlying conditions, leading to appropriate treatment.     

The potential role of public gardens as sentinels of plant invasion

Public gardens can help prevent detrimental effects of plant invasions by collecting and sharing data on taxa spreading from cultivation early in the invasion process, thereby acting as sentinels of plant invasion. Existing initiatives have called for public gardens to adopt measures preventing plant invasion, but it is unclear what actions individual gardens are implementing, as there is no formal mechanism for communicating their progress. This study used internal lists of escaping taxa from seven public gardens in the Midwestern United States and Canada to demonstrate how public gardens can collectively contribute data that is critical to assessing potential invasiveness. It also reveals methodological differences in how gardens develop their lists of escaping plants, leading to recommendations for standardization. Data pooled across gardens yielded 769 species spreading from cultivation at one or more gardens. Eight woody species were listed by all gardens despite not consistently being recognized as invasive by states and provinces containing the gardens; some species recorded by multiple gardens did not appear on any invasive lists. While it may be premature to call taxa escaping from cultivation at a few public gardens “invasive” or even “potentially invasive”, these plants should be monitored and evaluated with this information shared to facilitate stronger conclusions about risk. Thus, public gardens have a unique expertise in assisting invasive plant efforts as sentinels, particularly if challenges related to methodological inconsistencies and data sharing are suitably addressed, which is herein recommended through the adoption of a set of standardized guidelines.

     

Postprostatectomy erectile dysfunction: the role of penile rehabilitation

Radical prostatectomy has become the gold standard for the treatment of prostate cancer in patients who have a longer than 10-year life expectancy. Surgical treatment has led to severe quality-of-life issues in these patients, especially urinary incontinence and erectile dysfunction (ED). This article reviews the etiology and pathophysiology of postprostatectomy ED, and current management strategies for these patients.     

c-Type cytochrome-dependent formation of U(IV) nanoparticles by Shewanella oneidensis

Modern approaches for bioremediation of radionuclide contaminated environments are based on the ability of microorganisms to effectively catalyze changes in the oxidation states of metals that in turn influence their solubility. Although microbial metal reduction has been identified as an effective means for immobilizing highly-soluble uranium(VI) complexes in situ, the biomolecular mechanisms of U(VI) reduction are not well understood. Here, we show that c-type cytochromes of a dissimilatory metal-reducing bacterium, Shewanella oneidensis MR-1, are essential for the reduction of U(VI) and formation of extracellular UO(2) nanoparticles. In particular, the outer membrane (OM) decaheme cytochrome MtrC (metal reduction), previously implicated in Mn(IV) and Fe(III) reduction, directly transferred electrons to U(VI). Additionally, deletions of mtrC and/or omcA significantly affected the in vivo U(VI) reduction rate relative to wild-type MR-1. Similar to the wild-type, the mutants accumulated UO(2) nanoparticles extracellularly to high densities in association with an extracellular polymeric substance (EPS). In wild-type cells, this UO(2)-EPS matrix exhibited glycocalyx-like properties and contained multiple elements of the OM, polysaccharide, and heme-containing proteins. Using a novel combination of methods including synchrotron-based X-ray fluorescence microscopy and high-resolution immune-electron microscopy, we demonstrate a close association of the extracellular UO(2) nanoparticles with MtrC and OmcA (outer membrane cytochrome). This is the first study to our knowledge to directly localize the OM-associated cytochromes with EPS, which contains biogenic UO(2) nanoparticles. In the environment, such association of UO(2) nanoparticles with biopolymers may exert a strong influence on subsequent behavior including susceptibility to oxidation by O(2) or transport in soils and sediments.     

Differential roles of the co-stimulatory molecules GITR and CTLA-4 in the immune response to Trichinella spiralis

We investigated the roles of the regulatory molecules glucocorticoid-induced TNF receptor family-related protein (GITR) and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) in murine infection with the nematode parasite Trichinella spiralis. Expression of GITR and CTLA-4 was rapidly upregulated on cells in the mesenteric lymph nodes and spleen, with approximately 80% of CD4+ lymphocytes expressing GITR by day 7 post-infection, coinciding with release and dissemination of newborn larvae. As the infection progressed to the chronic muscle phase, expression of GITR returned to normal, whereas CTLA-4 was sustained as late as day 60. Mice treated with anti-GITR antibodies rapidly developed higher titres of parasite-specific IgG1, IgG2a, IgG2b and IgM than controls. This was accompanied by elevated background lymphocyte proliferation, but parasite establishment in the intestine or the muscle was unaffected. In contrast, treatment with anti-CTLA-4 antibody resulted in elevated serum IgE, enhanced production of interleukin-4 and interleukin-10, and lower numbers of parasites recovered from skeletal muscle. These results reveal different temporal and regulatory roles for CTLA-4 and GITR in immune responses to helminth infection.