Fzd7 (Frizzled-7) Expressed by Endothelial Cells Controls Blood Vessel Formation Through Wnt/β-Catenin Canonical Signaling.

Abstract OBJECTIVE: Vessel formation requires precise orchestration of a series of morphometric and molecular events controlled by a multitude of angiogenic factors and morphogens. Wnt/frizzled signaling is required for proper vascular formation. In this study, we investigated the role of the Fzd7 (frizzled-7) receptor in retinal vascular development and its relationship with the Wnt/β-catenin canonical pathway and Notch signaling. APPROACH AND RESULTS: Using transgenic mice, we demonstrated that Fzd7 is required for postnatal vascular formation. Endothelial cell (EC) deletion of fzd7 (fzd7ECKO) delayed retinal plexus formation because of an impairment in tip cell phenotype and a decrease in stalk cell proliferation. Dvl (dishevelled) proteins are a main component of Wnt signaling and play a functionally redundant role. We found that Dvl3 depletion in dvl1-/- mice mimicked the fzd7ECKO vascular phenotype and demonstrated that Fzd7 acted via β-catenin activation by showing that LiCl treatment rescued impairment in tip and stalk cell phenotypes induced in fzd7 mutants. Deletion of fzd7 or Dvl1/3 induced a strong decrease in Wnt canonical genes and Notch partners' expression. Genetic and pharmacological rescue strategies demonstrated that Fzd7 acted via β-catenin activation, upstream of Notch signaling to control Dll4 and Jagged1 EC expression. CONCLUSIONS: Fzd7 expressed by EC drives postnatal angiogenesis via activation of Dvl/β-catenin signaling and can control the integrative interaction of Wnt and Notch signaling during postnatal angiogenesis

Measuring subluxation of the hemiplegic shoulder: Reliability of a method

Objective: Subluxation of the shoulder after stroke can be measured according to the method described by Van Langenberghe and Hogan. Methods: To evaluate the reliability of this method, the shoulder radiographs of 25 patients were available for this study. Two independent raters each assessed these radiographs twice. Results: The intrarater reliability was good: percentage of agreement was 88 and 84%, weighted κ, 0.69 [95% confidence interval (CI), 0.38-1 0] and 0.78 (95% CI, 0.60-0.95) for raters 1 and 2, respectively. The interrater reliability was poor: percentage of agree ment was 36 and 28%, κ, 0.11 (95% CI, 0.0-0.31) and 0.09 (95% CI, 0.0-0.23) in sessions 1 and 2, respectively. Subsequently the original method was adjusted by com bining two categories (no subluxation and beginning subluxation) into one (“no clin ically important subluxation”). Conclusions: After this adjustment of the categories, the interrater reliability improved [percentage of agreement, 72%, and κ, 0.49 (95% CI, 0.18-0.80)], but did not reach acceptable values

TARP γ-7 selectively enhances synaptic expression of calcium-permeable AMPARs

Regulation of calcium-permeable AMPA receptors (CP-AMPARs) is crucial in normal synaptic function and neurological disease states. Although transmembrane AMPAR regulatory proteins (TARPs) such as stargazin (γ-2) modulate the properties of calcium-impermeable AMPARs (CI-AMPARs) and promote their synaptic targeting, the TARP-specific rules governing CP-AMPAR synaptic trafficking remain unclear. We used RNA interference to manipulate AMPAR-subunit and TARP expression in γ-2–lacking stargazer cerebellar granule cells—the classic model of TARP deficiency. We found that TARP γ-7 selectively enhanced the synaptic expression of CP-AMPARs and suppressed CI-AMPARs, identifying a pivotal role of γ-7 in regulating the prevalence of CP-AMPARs. In the absence of associated TARPs, both CP-AMPARs and CI-AMPARs were able to localize to synapses and mediate transmission, although their properties were altered. Our results also establish that TARPed synaptic receptors in granule cells require both γ-2 and γ-7 and reveal an unexpected basis for the loss of AMPAR-mediated transmission in stargazer mice

Aromatic N versus aromatic F: bioisosterism discovered in RNA base pairing interactions leads to a novel class of universal base analogs

The thermodynamics of base pairing is of fundamental importance. Fluorinated base analogs are valuable tools for investigating pairing interactions. To understand the influence of direct base–base interactions in relation to the role of water, pairing free energies between natural nucleobases and fluorinated analogs are estimated by potential of mean force calculations. Compared to pairing of AU and GC, pairing involving fluorinated analogs is unfavorable by 0.5–1.0 kcal mol−1. Decomposing the pairing free energies into enthalpic and entropic contributions reveals fundamental differences for Watson–Crick pairs compared to pairs involving fluorinated analogs. These differences originate from direct base–base interactions and contributions of water. Pairing free energies of fluorinated base analogs with natural bases are less unfavorable by 0.5–1.0 kcal mol−1 compared to non-fluorinated analogs. This is attributed to stabilizing C–F…H–N dipolar interactions and stronger N…H–C hydrogen bonds, demonstrating direct and indirect influences of fluorine. 7-methyl-7H-purine and its 9-deaza analog (Z) have been suggested as members of a new class of non-fluorinated base analogs. Z is found to be the least destabilizing universal base in the context of RNA known to date. This is the first experimental evidence for nitrogen-containing heterocylces as bioisosteres of aromatic rings bearing fluorine atoms

Does the use of the 2009 FIGO classification of endometrial cancer impact on indications of the sentinel node biopsy?

<p>Abstract</p> <p>Background</p> <p>Lymphadenectomy is debated in early stages endometrial cancer. Moreover, a new FIGO classification of endometrial cancer, merging stages IA and IB has been recently published. Therefore, the aims of the present study was to evaluate the relevance of the sentinel node (SN) procedure in women with endometrial cancer and to discuss whether the use of the 2009 FIGO classification could modify the indications for SN procedure.</p> <p>Methods</p> <p>Eighty-five patients with endometrial cancer underwent the SN procedure followed by pelvic lymphadenectomy. SNs were detected with a dual or single labelling method in 74 and 11 cases, respectively. All SNs were analysed by both H&E staining and immunohistochemistry. Presumed stage before surgery was assessed for all patients based on MR imaging features using the 1988 FIGO classification and the 2009 FIGO classification.</p> <p>Results</p> <p>An SN was detected in 88.2% of cases (75/85 women). Among the fourteen patients with lymph node metastases one-half were detected by serial sectioning and immunohistochemical analysis. There were no false negative case. Using the 1988 FIGO classification and the 2009 FIGO classification, the correlation between preoperative MRI staging and final histology was moderate with Kappa = 0.24 and Kappa = 0.45, respectively. None of the patients with grade 1 endometrioid carcinoma on biopsy and IA 2009 FIGO stage on MR imaging exhibited positive SN. In patients with grade 2-3 endometrioid carcinoma and stage IA on MR imaging, the rate of positive SN reached 16.6% with an incidence of micrometastases of 50%.</p> <p>Conclusions</p> <p>The present study suggests that sentinel node biopsy is an adequate technique to evaluate lymph node status. The use of the 2009 FIGO classification increases the accuracy of MR imaging to stage patients with early stages of endometrial cancer and contributes to clarify the indication of SN biopsy according to tumour grade and histological type.</p

Long-Term Relationships between Synaptic Tenacity, Synaptic Remodeling, and Network Activity

Long term time-lapse imaging reveals that individual synapses undergo significant structural remodeling not only when driven by activity, but also when network activity is absent, raising questions about how reliably individual synapses maintain connections

Hippocampal CA3 Transcriptome Signature Correlates with Initial Precipitating Injury in Refractory Mesial Temporal Lobe Epilepsy

Background: Prolonged febrile seizures constitute an initial precipitating injury (IPI) commonly associated with refractory mesial temporal lobe epilepsy (RMTLE). in order to investigate IPI influence on the transcriptional phenotype underlying RMTLE we comparatively analyzed the transcriptomic signatures of CA3 explants surgically obtained from RMTLE patients with (FS) or without (NFS) febrile seizure history. Texture analyses on MRI images of dentate gyrus were conducted in a subset of surgically removed sclerotic hippocampi for identifying IPI-associated histo-radiological alterations.Methodology/Principal Findings: DNA microarray analysis revealed that CA3 global gene expression differed significantly between FS and NFS subgroups. An integrative functional genomics methodology was used for characterizing the relations between GO biological processes themes and constructing transcriptional interaction networks defining the FS and NFS transcriptomic signatures and its major gene-gene links (hubs). Co-expression network analysis showed that: i) CA3 transcriptomic profiles differ according to the IPI; ii) FS distinctive hubs are mostly linked to glutamatergic signalization while NFS hubs predominantly involve GABAergic pathways and neurotransmission modulation. Both networks have relevant hubs related to nervous system development, what is consistent with cell genesis activity in the hippocampus of RMTLE patients. Moreover, two candidate genes for therapeutic targeting came out from this analysis: SSTR1, a relevant common hub in febrile and afebrile transcriptomes, and CHRM3, due to its putative role in epilepsy susceptibility development. MRI texture analysis allowed an overall accuracy of 90% for pixels correctly classified as belonging to FS or NFS groups. Histological examination revealed that granule cell loss was significantly higher in FS hippocampi.Conclusions/Significance: CA3 transcriptional signatures and dentate gyrus morphology fairly correlate with IPI in RMTLE, indicating that FS-RMTLE represents a distinct phenotype. These findings may shed light on the molecular mechanisms underlying refractory epilepsy phenotypes and contribute to the discovery of novel specific drug targets for therapeutic interventions

A comprehensive overview of radioguided surgery using gamma detection probe technology

The concept of radioguided surgery, which was first developed some 60 years ago, involves the use of a radiation detection probe system for the intraoperative detection of radionuclides. The use of gamma detection probe technology in radioguided surgery has tremendously expanded and has evolved into what is now considered an established discipline within the practice of surgery, revolutionizing the surgical management of many malignancies, including breast cancer, melanoma, and colorectal cancer, as well as the surgical management of parathyroid disease. The impact of radioguided surgery on the surgical management of cancer patients includes providing vital and real-time information to the surgeon regarding the location and extent of disease, as well as regarding the assessment of surgical resection margins. Additionally, it has allowed the surgeon to minimize the surgical invasiveness of many diagnostic and therapeutic procedures, while still maintaining maximum benefit to the cancer patient. In the current review, we have attempted to comprehensively evaluate the history, technical aspects, and clinical applications of radioguided surgery using gamma detection probe technology