Autophagy in Retinal Ganglion Cells in a Rhesus Monkey Chronic Hypertensive Glaucoma Model

Primary open angle glaucoma (POAG) is a neurodegenerative disease characterized by physiological intraocular hypertension that causes damage to the retinal ganglion cells (RGCs). In the past, RGC damage in POAG was suggested to have been attributed to RGC apoptosis. However, in the present study, we applied a model closer to human POAG through the use of a chronic hypertensive glaucoma model in rhesus monkeys to investigate whether another mode of progressive cell death, autophagy, was activated in the glaucomatous retinas. First, in the glaucomatous retinas, the levels of LC3B-II, LC3B-II/LC3B-I and Beclin 1 increased as demonstrated by Western blot analyses, whereas early or initial autophagic vacuoles (AVi) and late or degraded autophagic vacuoles (AVd) accumulated in the ganglion cell layer (GCL) and in the inner plexiform layer (IPL) as determined by transmission electron microscopy (TEM) analysis. Second, lysosome activity and autophagosome-lysosomal fusion increased in the RGCs of the glaucomatous retinas, as demonstrated by Western blotting against lysosome associated membrane protein-1 (LAMP1) and double labeling against LC3B and LAMP1. Third, apoptosis was activated in the glaucomatous eyes with increased levels of caspase-3 and cleaved caspase-3 and an increased number of TUNEL-positive RGCs. Our results suggested that autophagy was activated in RGCs in the chronic hypertensive glaucoma model of rhesus monkeys and that autophagy may have potential as a new target for intervention in glaucoma treatment.     

Pierisformotoxins A – D,Polyesterified Grayanane Diterpenoids from Pieris formosa and Their cAMP‐Decreasing Activities

Four highly acylated diterpenoids, designated as pierisformotoxins A–D ( 1 – 4 , resp.), along with 26 known compounds, were isolated from the flowers of Pieris formosa. Among them, pierisformotoxins A and B ( 1 and 2 , resp.) were new highly acylated grayanane diterpenoids, of which the five‐membered ring A has undergone an oxidative cleavage between C(3) and C(4), followed by lactonization, to give rise to a five‐membered lactone ring between C(3) and C(5), differing from the previously reported grayanane diterpenoids with a 5/7/6/5 ring system. Results of the cAMP‐regulation‐activity assay showed that pierisformotoxin C ( 3 ) at 10 μM (inhibitory ratio (IR): 10.1%) or 2 μM (9.8%), and pierisformotoxin B ( 2 ) at 50 μM (13.9%) significantly decreased the cAMP level in N1E‐115 neuroblastoma cells (p<0.05).     

三种PICC置管途径并发机械性静脉炎的比较分析

目的：比较经贵要静脉、肘正中静脉、头静脉三种不同途径进行PICC置管的成功率和置管术后机械性静脉炎的发生率,以寻找最佳置管途径。方法：对2010年－2012年入住我科的153例肿瘤患者PICC置管的成功率和置管术后机械性静脉炎的发生率,进行回顾性研究。结果：三种途径PICC置管成功率比较：贵要静脉〉肘正中静脉〉头静脉,差异有统计学意义（P〈0．05）。三种途径PICC置管术后机械性静脉炎的发生率比较：贵要静脉〈肘正中静脉〈头静脉,差异有统计学意义（P〈0．05）。结论：PICC置管的途径应首选贵要静脉,次选肘正中静脉,最后选头静脉。     

Derivation of endothelial cells from human embryonic stem cells in fully defined medium enables identification of lysophosphatidic acid and platelet activating factor as regulators of eNOS localization

The limited availability of human vascular endothelial cells (ECs) hampers research into EC function whilst the lack of precisely defined culture conditions for this cell type presents problems for addressing basic questions surrounding EC physiology. We aimed to generate endothelial progenitors from human pluripotent stem cells to facilitate the study of human EC physiology, using a defined serum-free protocol. Human embryonic stem cells (hESC-ECs) differentiated under serum-free conditions generated CD34⁺KDR⁺ endothelial progenitor cells after 6 days that could be further expanded in the presence of vascular endothelial growth factor (VEGF). The resultant EC population expressed CD31 and TIE2/TEK, took up acetylated low-density lipoprotein (LDL) and up-regulated expression of ICAM-1, PAI-1 and ET-1 following treatment with TNFα. Immunofluorescence studies indicated that a key mediator of vascular tone, endothelial nitric oxide synthase (eNOS), was localised to a perinuclear compartment of hESC-ECs, in contrast with the pan-cellular distribution of this enzyme within human umbilical vein ECs (HUVECs). Further investigation revealed that that the serum-associated lipids, lysophosphatidic acid (LPA) and platelet activating factor (PAF), were the key molecules that affected eNOS localisation in hESC-ECs cultures. These studies illustrate the feasibility of EC generation from hESCs and the utility of these cells for investigating environmental cues that impact on EC phenotype. We have demonstrated a hitherto unrecognized role for LPA and PAF in the regulation of eNOS subcellular localization.     

Two new rocaglamide derivatives from twigs of Aglaia odorata var. microphyllina

Phytochemical investigation of Aglaia odorata var. microphyllina led to the isolation of two new rocaglamide derivatives and three known ones. The structures of the two new compounds were elucidated as 8b-methoxy-desmethylrocaglamide (1) and 3′-hydroxy-8b-methoxy-rocaglamide (2) by spectroscopic techniques (IR, MS, 1D and 2D NMR) and comparing with published data. All the five compounds were evaluated for cytotoxic activity against K562 cell line by MTT method. The results indicated that the OH at 8b position was a decisive group for cytotoxic activity.     

Superiority of Trans-Oral over Trans-Nasal Sampling in Detecting Streptococcus pneumoniae Colonization in Adults

The human nasopharynx is the main reservoir for Streptococcus pneumoniae. We applied conventional and molecular methods to determine the prevalence of S. pneumoniae nasopharyngeal colonization in adults. Paired trans-orally and trans-nasally obtained nasopharyngeal samples from 268 parents of 24-month-old children were assessed for pneumococcal presence. Parents were classified as colonized when live pneumococci were recovered from either sample cultured on medium selective for S. pneumoniae. Of the 52 (19%) colonized parents 49 (18%) were culture-positive in trans-nasal and 10 (4%) in trans-oral samples. Bacterial growth was harvested from these cultures, DNA isolated and tested by quantitative-PCR (qPCR) targeting lytA and piaA genes specific for S. pneumoniae. A sample was considered positive if signals for both genes were detected. Altogether 105 (39%) individuals were classified as positive for pneumococcus by qPCR including 50 (19%) in trans-nasal and 94 (35%) in trans-oral settings. Although significantly more trans-nasal compared to trans-oral samples were culture-positive for S. pneumoniae at the primary diagnostic step (p<0.001) the opposite was observed in qPCR results (p<0.001). To confirm the presence of live pneumococcus in samples positive by qPCR but negative at the initial diagnostic step, we serially-diluted cell harvests, re-cultured and carefully examined for S. pneumoniae presence. Live pneumococci were recovered from an additional 43 parents including 42 positive in trans-oral and 4 in trans-nasal samples increasing the number of individuals culture- and qPCR-positive to 93 (35%) and positive by either of two methods to 107 (40%). There were significantly more trans-oral than trans-nasal samples positive for pneumococcus by both culture and qPCR (n = 71; 27%; vs. n = 50; 19%; p<0.05). Our data suggest that pneumococcal colonization is more common in adults than previously estimated and point towards the superiority of a trans-oral over a trans-nasal approach when testing adults for colonization with S. pneumoniae.     

Prognostic Significance of EBV Latent Membrane Protein 1 Expression in Lymphomas: Evidence from 15 Studies

Background

Epstein-Barr virus (EBV) infection has been associated with lymphoma development. EBV latent membrane protein 1 (LMP1) is essential for EBV-mediated transformation and progression of different human cells, including lymphocytes. This meta-analysis investigated LMP1 expression with prognosis of patients with lymphoma.

Methods

The electronic databases of PubMed, Embase, and Chinese Biomedicine Databases were searched. There were 15 published studies available for a random effects model analysis. Quality assessment was performed using the Newcastle-Ottawa Quality Assessment Scale for cohort studies. A funnel plot was used to investigate publication bias, and sources of heterogeneity were identified by meta-regression analysis. The combined hazard ratios (HR) and their corresponding 95% confidence intervals of LMP1 expression were calculated by comparison to the overall survival.

Results

Overall, there was no statistical significance found between LMP1 expression and survival of lymphoma patients (HR 1.25 [95% CI, 0.92–1.68]). In subgroup analyses, LMP1 expression was associated with survival in patients with non-Hodgkin lymphoma (NHL) (HR  = 1.84, 95% CI: 1.02–3.34), but not with survival of patients with Hodgkin disease (HD) (HR  =  1.03, 95% CI: 0.74–1.44). In addition, significant heterogeneity was present and the meta-regression revealed that the outcome of analysis was mainly influenced by the cutoff value.

Conclusions

This meta-analysis demonstrated that LMP1 expression appears to be an unfavorable prognostic factor for overall survival of NHL patients. The data suggested that EBV infection and LMP1 expression may be an important factor for NHL development or progression.     

A Hypomorphic Lsd1 Allele Results in Heart Development Defects in Mice

Lysine-specific demethylase 1 (Lsd1/Aof2/Kdm1a), the first enzyme with specific lysine demethylase activity to be described, demethylates histone and non-histone proteins and is essential for mouse embryogenesis. Lsd1 interacts with numerous proteins through several different domains, most notably the tower domain, an extended helical structure that protrudes from the core of the protein. While there is evidence that Lsd1-interacting proteins regulate the activity and specificity of Lsd1, the significance and roles of such interactions in developmental processes remain largely unknown. Here we describe a hypomorphic Lsd1 allele that contains two point mutations in the tower domain, resulting in a protein with reduced interaction with known binding partners and decreased enzymatic activity. Mice homozygous for this allele die perinatally due to heart defects, with the majority of animals suffering from ventricular septal defects. Molecular analyses revealed hyperphosphorylation of E-cadherin in the hearts of mutant animals. These results identify a previously unknown role for Lsd1 in heart development, perhaps partly through the control of E-cadherin phosphorylation.