Citations

Abstract Background Illumina paired-end sequencing has been increasingly popular for 16S rRNA gene-based microbiota profiling. It provides higher phylogenetic resolution than single-end reads due to a longer read length. However, the reverse read (R2) often has significant low base quality, and a large proportion of R2s will be discarded after quality control, resulting in a mixture of paired-end and single-end reads. A typical 16S analysis pipeline usually processes either paired-end or single-end reads but not a mixture. Thus, the quantification accuracy and statistical power will be reduced due to the loss of a large amount of reads. As a result, rare taxa may not be detectable with the paired-end approach, or low taxonomic resolution will result in a single-end approach. Results To have both the higher phylogenetic resolution provided by paired-end reads and the higher sequence coverage by single-end reads, we propose a novel OTU-picking pipeline, hybrid-denovo, that can process a hybrid of single-end and paired-end reads. Using high-quality paired-end reads as a gold standard, we show that hybrid-denovo achieved the highest correlation with the gold standard and performed better than the approaches based on paired-end or single-end reads in terms of quantifying the microbial diversity and taxonomic abundances. By applying our method to a rheumatoid arthritis (RA) data set, we demonstrated that hybrid-denovo captured more microbial diversity and identified more RA-associated taxa than a paired-end or single-end approach. Conclusions Hybrid-denovo utilizes both paired-end and single-end 16S sequencing reads and is recommended for 16S rRNA gene targeted paired-end sequencing data.

Melanocortin 2 receptor accessory protein (MRAP) is highly expressed in adrenal gland and adipose tissue. In adrenal cells, MRAP is essential for adrenocorticotropic hormone (ACTH)–induced activation of the cAMP/protein kinase A (PKA) pathway by melanocortin 2 receptor (MC2R), leading to glucocorticoid production and secretion. Although ACTH was known to stimulate PKA-dependent lipolysis, the functional involvement of MRAP in adipocyte metabolism remains incompletely defined. Herein, we found that knockdown or overexpression of MRAP in 3T3-L1 adipocytes reduced or increased ACTH-induced lipolysis, respectively. Moreover, an unbiased proteomics screen and coimmunoprecipitation analysis identified Gαs as a novel interacting partner of MRAP. An MRAP mutant disabled in Gαs association failed to augment the activation of PKA and lipolytic response to ACTH. Furthermore, compared with wild-type mice, transgenic mice (aP2-MRAP) overexpressing MRAP fat specifically exhibited increased lipolytic response to ACTH. When fed a high-fat diet (HFD), the transgenic mice displayed a significant decrease in the gain of adiposity and body weight as well as an improvement in glucose and insulin tolerance. These phenotypes were accompanied by increased adipose expression of genes for mitochondrial fatty acid oxidation and thermogenesis, and overall energy expenditure. Collectively, our data strongly suggest that MRAP plays a critical role in the regulation of ACTH-induced adipose lipolysis and whole-body energy balance.

Breast implant-associated anaplastic large cell lymphoma (BI-ALCL) is a rare T-cell lymphoma that arises around breast implants. Most patients manifest with periprosthetic effusion, whereas a subset of patients develops a tumor mass or lymph node involvement (LNI). The aim of this study is to describe the pathologic features of lymph nodes from patients with BI-ALCL and assess the prognostic impact of LNI. Clinical findings and histopathologic features of lymph nodes were assessed in 70 patients with BI-ALCL. LNI was defined by the histologic demonstration of ALCL in lymph nodes. Fourteen (20%) patients with BI-ALCL had LNI, all lymph nodes involved were regional, the most frequent were axillary (93%). The pattern of involvement was sinusoidal in 13 (92.9%) cases, often associated with perifollicular, interfollicular, and diffuse patterns. Two cases had Hodgkin-like patterns. The 5-year overall survival was 75% for patients with LNI and 97.9% for patients without LNI at presentation (P=0.003). Six of 49 (12.2%) of patients with tumor confined by the capsule had LNI, compared with LNI in 8/21 (38%) patients with tumor beyond the capsule. Most patients with LNI achieved complete remission after various therapeutic approaches. Two of 14 (14.3%) patients with LNI died of disease compared with 0/56 (0%) patients without LNI. Twenty percent of patients with BI-ALCL had LNI by lymphoma, most often in a sinusoidal pattern. We conclude that BI-ALCL beyond capsule is associated with a higher risk of LNI. Involvement of lymph nodes was associated with decreased overall survival. Misdiagnosis as Hodgkin lymphoma is a pitfall.

PurposeDynamic manganese‐enhanced MRI (MEMRI) allows assessment of tissue viability by tracing manganese uptake. We aimed to develop a rapid T1 mapping method for dynamic MEMRI to facilitate assessments of murine kidney viability.MethodsA multi‐slice saturation recovery fast spin echo (MSRFSE) was developed, validated, and subsequently applied in dynamic MEMRI at 16.4T on ischemic mouse kidneys after 4 weeks of unilateral renal artery stenosis (RAS). Baseline T1 values and post‐contrast R1 (1/T1) changes were measured in cortex (CO), outer (OSOM), inner (ISOM) strips of outer medulla, and inner medulla (IM).ResultsValidation studies showed strong agreement between MSRFSE and an established saturation recovery Look‐Locker method. Baseline T1 (s) increased in the stenotic kidney CO (2.10 [1.95–2.56] vs. 1.88 [1.81–2.00], P = 0.0317) and OSOM (2.17 [2.05–2.33] vs. 1.96 [1.87–2.00], P = 0.0075) but remained unchanged in ISOM and IM. This method allowed a temporal resolution of 1.43 min in dynamic MEMRI. Mn2+ uptake and retention decreased in stenotic kidneys, particularly in the OSOM (ΔR1: 0.48 [0.38–0.56] vs. 0.64 [0.61–0.69] s−1, P < 0.0001).ConclusionDynamic MEMRI by MSRFSE detected decreased cellular viability and discerned the regional responses to RAS. This technique may provide a valuable tool for noninvasive evaluation of renal viability. Magn Reson Med 80:190–199, 2018. © 2017 International Society for Magnetic Resonance in Medicine.

Abstract Purpose: Intratumoral androgen synthesis (IAS) is a key mechanism promoting androgen receptor (AR) reactivation and antiandrogen resistance in castration-resistant prostate cancer (CRPC). However, signaling pathways driving aberrant IAS remain poorly understood. Experimental Design: The effect of components of the AKT-RUNX2-osteocalcin (OCN)–GPRC6A–CREB signaling axis on expression of steroidogenesis genes CYP11A1 and CYP17A1 and testosterone level were examined in PTEN-null human prostate cancer cell lines. Pten knockout mice were used to examine the effect of Runx2 heterozygous deletion or abiraterone acetate (ABA), a prodrug of the CYP17A1 inhibitor abiraterone on Cyp11a1 and Cyp17a1 expression, testosterone level and tumor microenvironment (TME) remodeling in vivo. Results: We uncovered that activation of the AKT–RUNX2–OCN–GPRC6A–CREB signaling axis induced expression of CYP11A1 and CYP17A1 and testosterone production in PTEN-null prostate cancer cell lines in culture. Deletion of Runx2 in Pten homozygous knockout prostate tumors decreased Cyp11a1 and Cyp17a1 expression, testosterone level, and tumor growth in castrated mice. ABA treatment also inhibited testosterone synthesis and alleviated Pten loss-induced tumorigenesis in vivo. Pten deletion induced TME remodeling, but Runx2 heterozygous deletion or ABA treatment reversed the effect of Pten loss by decreasing expression of the collagenase Mmp9. Conclusions: Abnormal RUNX2 activation plays a pivotal role in PTEN loss-induced IAS and TME remodeling, suggesting that the identified signaling cascade represents a viable target for effective treatment of PTEN-null prostate cancer, including CRPC. Clin Cancer Res; 24(4); 834–46. ©2017 AACR.

Discogenic low back pain (DLBP) is extremely common and costly. Effective treatments are lacking due to DLBP's unknown pathogenesis. Currently, there are no in vivo mouse models of DLBP, which restricts research in this field. The aim of this study was to establish a reliable DLBP model in mouse that captures the pathological changes in the disc and allows longitudinal pain testing. The model was generated by puncturing the mouse lumbar discs (L4/5, L5/6, and L6/S1) and removing the nucleus pulposus using a microscalpel under the microscope. Histology, molecular pathways, and pain‐related behaviors were examined. Over 12 weeks post‐surgery, animals displayed the mechanical, heat, and cold hyperalgesia along with decreased burrowing and rearing. Histology showed progressive disc degeneration with loss of disc height, nucleus pulposus reduction, proteoglycan depletion, and annular fibrotic disorganization. Immunohistochemistry revealed a substantial increase in inflammatory mediators at 2 and 4 weeks. Nerve growth factor was upregulated from 2 weeks to the end of the experiment. Nerve fiber ingrowth was induced in the injured discs after 4 weeks. Disc‐puncture also produced an upregulation of neuropeptides in dorsal root ganglia neurons and an activation of glial cells in the spinal cord dorsal horn. These findings indicate that the cellular and structural changes in discs, as well as peripheral and central nervous system plasticity, paralleled persistent, and robust behavioral pain responses. Therefore, this mouse DLBP model could be used to investigate mechanisms underlying discogenic pain, thereby facilitating effective drug screening and development of treatments for DLBP.

Background and Purpose— White matter (WM) ischemic injury, a major neuropathological feature of cerebral small vessel diseases, is an important cause of vascular cognitive impairment in later life. The pathogenesis of demyelination after WM ischemic damage are often accompanied by microglial activation. Fingolimod (FTY720) was approved for the treatment of multiple sclerosis for its immunosuppression property. In this study, we evaluated the neuroprotective potential of FTY720 in a WM ischemia model. Methods— Chronic WM ischemic injury model was induced by bilateral carotid artery stenosis. Cognitive function, WM integrity, microglial activation, and potential pathway involved in microglial polarization were assessed after bilateral carotid artery stenosis. Results— Disruption of WM integrity was characterized by demyelination in the corpus callosum and disorganization of Ranvier nodes using Luxol fast blue staining, immunofluorescence staining, and electron microscopy. In addition, radial maze test demonstrated that working memory performance was decreased at 1-month post–bilateral carotid artery stenosis–induced injury. Interestingly, FTY720 could reduce cognitive decline and ameliorate the disruption of WM integrity. Mechanistically, cerebral hypoperfusion induced microglial activation, production of associated proinflammatory cytokines, and priming of microglial polarization toward the M1 phenotype, whereas FTY720 attenuated microglia-mediated neuroinflammation after WM ischemia and promoted oligodendrocytogenesis by shifting microglia toward M2 polarization. FTY720’s effect on microglial M2 polarization was largely suppressed by selective signal transducer and activator of transcription 3 (STAT3) blockade in vitro, revealing that FTY720-enabled shift of microglia from M1 to M2 polarization state was possibly mediated by STAT3 signaling. Conclusions— Our study suggested that FTY720 might be a potential therapeutic drug targeting brain inflammation by skewing microglia toward M2 polarization after chronic cerebral hypoperfusion.