The pro-inflammatory cytokine interleukin (IL)-1β is critical for normal hippocampus (HP)-dependent cognition, whereas high levels can disrupt memory and are implicated in neurodegeneration. However, the cellular source of IL-1β during learning has not been shown, and little is known about the risk factors leading to cytokine dysregulation within the HP. We have reported that neonatal bacterial infection in rats leads to marked HP-dependent memory deficits in adulthood. However, deficits are only observed if unmasked by a subsequent immune challenge (lipopolysaccharide, LPS) around the time of learning. These data implicate a long-term change within the immune system that, upon activation with the “second hit”, LPS, acutely impacts the neural processes underlying memory. Indeed, inhibiting brain IL-1β prior to the LPS challenge prevents memory impairment in neonatally-infected (NI) rats. We aimed to determine the cellular source of IL-1β during normal learning, and thereby lend insight into the mechanism by which this cytokine is enduringly altered by early-life infection. We show for the first time that CD11b+ enriched cells are the source of IL-1β during normal HP-dependent learning. CD11b+ cells from NI rats are functionally sensitized within the adult HP and produce exaggerated IL-1β ex vivo compared to controls. However, an exaggerated IL-1β response in vivo requires LPS prior to learning. Moreover, preventing microglial activation during learning prevents memory impairment in NI rats, even following an LPS challenge. Thus, early-life events can significantly modulate normal learning-dependent cytokine activity within the HP, via a specific, enduring impact on brain microglial function.

Objective To assess the influence of patient preferences and urologist recommendations in treatment decisions for clinically localized prostate cancer. Methods We enrolled 257 men with clinically localized prostate cancer (PSA < 20; Gleason 6 or 7) seen by urologists (primarily residents and fellows) in 4 Veterans Affairs Medical Centers. We measured patients’ baseline preferences prior to their urology appointments, including initial treatment preference, cancer-related anxiety, and interest in sex. In longitudinal follow-up, we determined which treatment patients received. We used hierarchical logistic regression to determine the factors that predicted treatment received (active treatment vs. active surveillance) and urologist recommendations. We also conducted a directed content analysis of recorded clinical encounters to determine if urologists discussed patients’ interest in sex. Results Patients’ initial treatment preferences did not predict receipt of active treatment versus surveillance (Δχ2 (4) = 3.67, p = .45). Instead, receipt of active treatment was predicted primarily by urologists’ recommendations (Δχ2(2) = 32.81 p < .001). Urologists’ recommendations, in turn, were influenced heavily by medical factors (age and Gleason score) but unrelated to patient preferences (Δχ2 (6) = 0, p = 1). Urologists rarely discussed patients’ interest in sex (< 15% of appointments). Conclusions Patients’ treatment decisions were based largely upon urologists’ recommendations, which, in turn, were based on medical factors (age and Gleason score) and not on patients’ personal views of the relative pros and cons of treatment alternatives.

The goal of this study was to design and evaluate a rapid screen to identify metagenomic clones that produce biologically active small molecules. We built metagenomic libraries with DNA from soil on the floodplain of the Tanana River in Alaska. We extracted DNA directly from the soil and cloned it into fosmid and bacterial artificial chromosome vectors, constructing eight metagenomic libraries that contain 53,000 clones with inserts ranging from 1 to 190 kb. To identify clones of interest, we designed a high throughput "intracellular" screen, designated METREX, in which metagenomic DNA is in a host cell containing a biosensor for compounds that induce bacterial quorum sensing. If the metagenomic clone produces a quorum-sensing inducer, the cell produces green fluorescent protein (GFP) and can be identified by fluorescence microscopy or captured by fluorescence-activated cell sorting. Our initial screen identified 11 clones that induce and two that inhibit expression of GFP. The intracellular screen detected quorum-sensing inducers among metagenomic clones that a traditional overlay screen would not. One inducing clone carries a LuxI homologue that directs the synthesis of an N-acyl homoserine lactone quorum-sensing signal molecule. The LuxI homologue has 62% amino acid sequence identity to its closest match in GenBank, AmfI from Pseudomonas fluorescens, and is on a 78-kb insert that contains 67 open reading frames. Another inducing clone carries a gene with homology to homocitrate synthase. Our results demonstrate the power of an intracellular screen to identify functionally active clones and biologically active small molecules in metagenomic libraries.

Neurogenesis is a well-characterized phenomenon within the dentate gyrus (DG) of the adult hippocampus. Environmental enrichment (EE) in rodents increases neurogenesis, enhances cognition, and promotes recovery from injury. However, little is known about the effects of EE on glia (astrocytes and microglia). Given their importance in neural repair, we predicted that EE would modulate glial phenotype and/or function within the hippocampus. Adult male rats were housed either 12 h/day in an enriched environment or in a standard home cage. Rats were injected with BrdU at 1 week, and after 7 weeks, half of the rats from each housing group were injected with lipopolysaccharide (LPS), and cytokine and chemokine expression was assessed within the periphery, hippocampus and cortex. Enriched rats had a markedly blunted pro-inflammatory response to LPS within the hippocampus. Specifically, expression of the chemokines Ccl2, Ccl3 and Cxcl2, several members of the tumor necrosis factor (TNF) family, and the pro-inflammatory cytokine IL-1β were all significantly decreased following LPS administration in EE rats compared to controls. EE did not impact the inflammatory response to LPS in the cortex. Moreover, EE significantly increased both astrocyte (GFAP+) and microglia (Iba1+) antigen expression within the DG, but not in the CA1, CA3, or cortex. Measures of neurogenesis were not impacted by EE (BrdU and DCX staining), although hippocampal BDNF mRNA was significantly increased by EE. This study demonstrates the importance of environmental factors on the function of the immune system specifically within the brain, which can have profound effects on neural function.

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The Brazilian Cerrado is the second largest biome in Brazil and is considered a biodiversity hotspot. In this work, we compared the bacterial communities in Cerrado soil associated with four types of native vegetation (Cerrado Denso, Cerrado sensu stricto, Campo Sujo, and Mata de Galeria) by ribosomal RNA intergenic spacer analysis, terminal fragment restriction length polymorphism and pyrosequencing. The fingerprinting results were very similar. The bacterial communities of Cerrado Denso and Cerrado sensu stricto grouped together and were distinct from those in Campo Sujo and Mata de Galeria. Pyrosequencing generated approximately 40,000 16S rRNA gene sequences per sample and allowed the identification of 17 phyla in soil samples under Cerrado vegetation. Acidobacteria were dominant in all areas studied with a relative frequency of 40-47 %, followed closely by Proteobacteria accounting for 34-40 % of the sequences. Results from all molecular techniques used suggested that the bacterial communities of Cerrado sensu stricto and Cerrado Denso are very similar to each other, while Campo Sujo forms a separate group, and Mata de Galeria is the most distinct with higher species richness. This is the first extensive study of native Cerrado soil microbiota, an important but endangered biome.

Ralstonia solanacearum race 3, biovar 2 is a soilborne bacterium that causes potato brown rot disease in temperate and subtropical climates. Recent outbreaks of this disease in Europe have caused serious losses, but the pathogen had not been identified in the United States. However, in 1999, strains of R. solanacearum were isolated from wilting geraniums growing in Wisconsin greenhouses. Physiological and biochemical tests of the Wisconsin strains and a similar strain from South Dakota demonstrated that the strains belong to R. solanacearum subgroup biovar 2, which is largely synonymous with the race 3 subgroup, a classification based on host range. These results were confirmed by polymerase chain reaction analyses in which race 3, biovar 2-specific primers amplified a fragment of the expected size. This is the first report of race 3, biovar 2 in the United States, and it is the first known occurrence of race 3, biovar 2 in Wiscon-sin. The geranium strains were highly pathogenic on both geranium and potato. The presence of R. solanacearum race 3, biovar 2 in the United States raises concern that the bacterium could move from ornamental plants into potato fields, where it could cause both direct economic damage and quarantine problems. A commercial indirect enzyme-linked immunosorbent assay for R. solanacearum produced some false negatives for these strains, indicating that current indexing may not be sufficient to identify this destructive pathogen.

Background More than 1 in 4 Americans report difficulty paying medical bills. Cost-reducing strategies discussed during outpatient physician visits remain poorly characterized. Objective We sought to determine how often patients and physicians discuss healthcare costs during outpatient visits and what strategies, if any, they discussed to lower patient out-of-pocket costs. Design Retrospective analysis of dialogue from 1,755 outpatient visits in community-based practices nationwide from 2010–2014. The study population included 677 patients with breast cancer, 422 with depression, and 656 with rheumatoid arthritis visiting 56 oncologists, 36 psychiatrists, and 26 rheumatologists, respectively. Results Thirty percent of visits contained cost conversations (95% confidence interval [CI], 28 to 32). Forty-four percent of cost conversations involved discussion of cost-saving strategies (95% CI, 40 to 48; median duration, 68 seconds). We identified 4 strategies to lower costs without changing the care plan – in order of overall frequency, (1) Changing logistics of care; (2) Facilitating copay assistance; (3) Providing free samples; (4) Changing/adding insurance plans – and 4 strategies to reduce costs by changing the care plan – (1) Switching to lower-cost alternative therapy/diagnostic; (2) Switching from brand name to generic; (3) Changing dosage/frequency; (4) Stopping/withholding interventions. Strategies were relatively consistent across health conditions, except for switching to lower-cost alternative (more common in breast oncology), and providing free samples (more common in depression). Limitation Focus on three conditions with potentially high out-of-pocket costs. Conclusions Despite price opacity, physicians and patients discuss a variety of out-of-pocket cost reduction strategies during clinic visits. Almost half of cost discussions mention one or more cost-saving strategies, with more frequent mention of those not requiring care-plan changes.