Impact of Different Fecal Processing Methods on Assessments of Bacterial Diversity in the Human Intestine.

The intestinal microbiota are integral to understanding the relationships between nutrition and health. Therefore, fecal sampling and processing protocols for metagenomic surveys should be sufficiently robust, accurate, and reliable to identify the microorganisms present. We investigated the use of different fecal preparation methods on the bacterial community structures identified in human stools. Complete stools were collected from six healthy individuals and processed according to the following methods: (i) randomly sampled fresh stool, (ii) fresh stool homogenized in a blender for 2 min, (iii) randomly sampled frozen stool, and (iv) frozen stool homogenized in a blender for 2 min, or (v) homogenized in a pneumatic mixer for either 10, 20, or 30 min. High-throughput DNA sequencing of the 16S rRNA V4 regions of bacterial community DNA extracted from the stools showed that the fecal microbiota remained distinct between individuals, independent of processing method. Moreover, the different stool preparation approaches did not alter intra-individual bacterial diversity. Distinctions were found at the level of individual taxa, however. Stools that were frozen and then homogenized tended to have higher proportions of Faecalibacterium, Streptococcus, and Bifidobacterium and decreased quantities of Oscillospira, Bacteroides, and Parabacteroides compared to stools that were collected in small quantities and not mixed prior to DNA extraction. These findings indicate that certain taxa are at particular risk for under or over sampling due to protocol differences. Importantly, homogenization by any method significantly reduced the intra-individual variation in bacteria detected per stool. Our results confirm the robustness of fecal homogenization for microbial analyses and underscore the value of collecting and mixing large stool sample quantities in human nutrition intervention studies

Understanding Information and Knowledge Sharing in Online Communities: Emerging Research Approaches

Social media have become an important component of contemporary information ecosystems. People use social media systems, such as Twitter, Facebook, YouTube, and Tumblr to communicate ideas and information needs, seek advice and solve problems, show appreciation and disagreement with a person or issue. These tools facilitate the emergence of communities, often resembling the communities of practice that arise in workplaces and educational institutions, where a common interest, identity and set of norms and structures for communicating develop through interaction. But while it seems easy to suck in data streams from social media to understand online communities, making sense of the vast data sets has been challenging. The issues include not just the tools and methods for extracting and synthesizing large data sets like the Twitter Firehose, they also extend to the ethical and responsible use and reporting of this data for academic and commercial purposes. This panel will focus on methodological approaches and research strategies for the study of social media communities, in particular web 2.0 tools that play an important role in the North American cultural landscape

Metastatic seminoma and grade 1 follicular lymphoma presenting concurrently in a supraclavicular lymph node: a case report

An asymptomatic 67-year-old man presented with a left supraclavicular lymph node that enlarged over a 2-month period which was biopsied. Pathologic features were consistent with involvement by metastatic seminoma and follicular lymphoma, follicular pattern, grade 1 (of 3). Staging Positron Emission Tomography/Computed Tomography scans indicated several areas of enlarged lymph nodes. The patient completed chemotherapy with bleomycin, etoposide, and cisplatin chemotherapy. This is the first reported case of metastatic seminoma and follicular lymphoma occurring in the same lymph node. No obvious pathophysiologic link exists between these two malignancies and there are no shared common risk factors. Given the natural history of these two malignancies, if this patient develops recurrent lymphadenopathy, it will be difficult to identify whether the enlarged lymph nodes represent recurrent seminoma or follicular lymphoma without a biopsy of each pathologically enlarged node. Similarly, Fluorodeoxyglucose- Positron Emission Tomography is known to be active in both seminoma and follicular lymphoma, making this scan non-specific in this patient. Finally, this patient had no baseline elevation in any germ cell tumor marker. Thus, serum tumor markers cannot be relied upon as surrogates for response to chemotherapy or as identifiers of relapsed seminoma

Using The Rat Grimace Scale to Detect Orofacial Pain in Mechanically-induced Temporomandibular Joint Pain in Rats

Introduction: Orofacial pain in animal models of TMJ disorders is typically evaluated by measuring evoked reflexive responses. Since the rat grimace scale (RGS) was adopted recently to assess spontaneous pain in other pathologies, this study evaluated its effectiveness for TMJ pain in the rat. RGS was evaluated using a well-defined pain model of TMJ loading. Material and Methods: Female Holtzman rats were assigned to separate groups: loading (n=10); sham (n=4); loading with naproxen (n=4) or vehicle (n=3) on days 4 and 5 after pain developed. Jaw loading was imposed for 7 consecutive days under anesthesia by repeated mouth-opening for 1hr. Sham had no mouth-opening. Naproxen or vehicle (1mg/kg) was given intravenously. Rats were videotaped for 30mins daily after loading, and for 7 days after loading was stopped. Images were randomized and quantitatively scored using 4 action units: orbital tightening, nose/cheek flattening, ear change, whisker change. The RGS score was compared between groups using a repeated-measures ANOVA and Tukey\u27s post-hoc test. Results: Loading induced significantly higher (p\u3c0.001) RGS scores than sham on days 1 and 5. After loading was stopped, RGS scores returned to sham levels for the remainder of test days. Naproxen injection significantly lowered (p\u3c0.001) RGS scores from loading alone on day 7. Conclusion: Orofacial pain can be detected by the RGS, which may provide a useful new method to evaluate TMJ pain

Hyperpolarized 13C-pyruvate MRI detects real-time metabolic flux in prostate cancer metastases to bone and liver: a clinical feasibility study.

BackgroundHyperpolarized (HP) 13C-pyruvate MRI is a stable-isotope molecular imaging modality that provides real-time assessment of the rate of metabolism through glycolytic pathways in human prostate cancer. Heretofore this imaging modality has been successfully utilized in prostate cancer only in localized disease. This pilot clinical study investigated the feasibility and imaging performance of HP 13C-pyruvate MR metabolic imaging in prostate cancer patients with metastases to the bone and/or viscera.MethodsSix patients who had metastatic castration-resistant prostate cancer were recruited. Carbon-13 MR examination were conducted on a clinical 3T MRI following injection of 250 mM hyperpolarized 13C-pyruvate, where pyruvate-to-lactate conversion rate (kPL) was calculated. Paired metastatic tumor biopsy was performed with histopathological and RNA-seq analyses.ResultsWe observed a high rate of glycolytic metabolism in prostate cancer metastases, with a mean kPL value of 0.020 ± 0.006 (s-1) and 0.026 ± 0.000 (s-1) in bone (N = 4) and liver (N = 2) metastases, respectively. Overall, high kPL showed concordance with biopsy-confirmed high-grade prostate cancer including neuroendocrine differentiation in one case. Interval decrease of kPL from 0.026 at baseline to 0.015 (s-1) was observed in a liver metastasis 2 months after the initiation of taxane plus platinum chemotherapy. RNA-seq found higher levels of the lactate dehydrogenase isoform A (Ldha,15.7 ± 0.7) expression relative to the dominant isoform of pyruvate dehydrogenase (Pdha1, 12.8 ± 0.9).ConclusionsHP 13C-pyruvate MRI can detect real-time glycolytic metabolism within prostate cancer metastases, and can measure changes in quantitative kPL values following treatment response at early time points. This first feasibility study supports future clinical studies of HP 13C-pyruvate MRI in the setting of advanced prostate cancer

Local treatment and treatment-related adverse effects among patients with advanced prostate cancer

IMPORTANCE: Recent data suggest that local treatment with radical prostatectomy or radiation may improve survival outcomes in men with advanced prostate cancer. However, evidence is lacking on treatment-related adverse effects among men with advanced prostate cancer. OBJECTIVE: To assess the association of local treatment on treatment-related adverse effects among men diagnosed with advanced prostate cancer. DESIGN, SETTING, AND PARTICIPANTS: This cohort study assessed men diagnosed with advanced prostate cancer (defined as T4, N1, and/or M1 prostate cancer) between January 1, 1999, and December 31, 2013, with follow-up through December 31, 2021, who were treated at Veterans Health Administration medical centers. EXPOSURE: Local treatment with radical prostatectomy or radiation. MAIN OUTCOMES AND MEASURES: Main outcomes were treatment-related adverse effects, including constitutional, gastrointestinal, pain, sexual function, and urinary function conditions, at 3 intervals after initial treatment (≤1 year, \u3e1 to ≤2 years, and \u3e2 to ≤5 years) after initial treatment. RESULTS: This cohort study consisted of 5502 men (mean [SD] age, 68.7 [10.3] years) diagnosed with advanced prostate cancer. Of the cohort, 1705 men (31.0%) received local treatment. There was a high prevalence of adverse conditions in men receiving both local and nonlocal treatment, and these adverse conditions persisted for more than 2 years to 5 years or less after initial treatment. A total of 916 men (75.2%) with initial local treatment and 897 men (67.1%) with initial nonlocal treatment reported the presence of at least 1 adverse condition for more than 2 years to 5 years or less after initial treatment. In the first year, local treatment (vs nonlocal) was associated with adverse gastrointestinal (multivariable-adjusted odds ratio [AOR], 4.08; 95% CI, 3.06-5.45), pain (AOR, 1.57; 95% CI, 1.35-1.83), sexual (AOR, 2.96; 95% CI, 2.42-3.62), and urinary (AOR, 2.25; 95% CI, 1.90-2.66) conditions. Local treatment (without secondary treatment) remained significantly associated with adverse gastrointestinal (AOR, 2.39; 95% CI, 1.52-3.77), sexual (AOR, 3.36; 95% CI, 2.56-4.41), and urinary (AOR, 1.39; 95% CI, 1.09-1.78) conditions at more than 2 years to 5 years or less after treatment. CONCLUSIONS AND RELEVANCE: In this cohort study of men with advanced prostate cancer, local treatment was associated with persistent treatment-related adverse effects across multiple domains. These results suggest that patients and clinicians should consider the adverse effects of local treatment when making treatment decisions in the setting of advanced prostate cancer