Synapse Formation Activates a Transcriptional Program for Persistent Enhancement in the Bi-directional Transport of Mitochondria

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Factors influencing stomatal conductance in response to water availability in grapevine: a meta‐analysis

The main factors regulating grapevine response to decreasing water availability were assessed under statistical support using published data related to leaf water relations in an extensive range of scion and rootstock genotypes. Matching leaf water potential (Ψ_leaf) and stomatal conductance (g_s) data were collected from peer‐reviewed literature with associated information. The resulting database contained 718 data points from 26 different Vitis vinifera varieties investigated as scions, 15 non‐V. vinifera rootstock genotypes and 11 own‐rooted V. vinifera varieties. Linearised data were analysed using the univariate general linear model (GLM) with factorial design including biological (scion and rootstock genotypes), methodological and environmental (soil) fixed factors. The first GLM performed on the whole database explained 82.4% of the variability in data distribution having the rootstock genotype the greatest contribution to variability (19.1%) followed by the scion genotype (16.2%). A classification of scions and rootstocks according to their mean predicted g_s in response to moderate water stress was generated. This model also revealed that g_s data obtained using a porometer were in average 2.1 times higher than using an infra‐red gas analyser. The effect of soil water‐holding properties was evaluated in a second analysis on a restricted database and showed a scion‐dependant effect, which was dominant over rootstock effect, in predicting g_s values. Overall the results suggest that a continuum exists in the range of stomatal sensitivities to water stress in V. vinifera, rather than an isohydric–anisohydric dichotomy, that is further enriched by the diversity of scion‐rootstock combinations and their interaction with different soils.     

Willingness to Pay for Cataract Surgery Provided by a Senior Surgeon in Urban Southern China

Purpose

To study willingness to pay for cataract surgery and surgical service provided by a senior cataract surgeon in urban Southern China.

Methods

This study was a cross-sectional willingness-to-pay (WTP) interview using bidding formats. Two-hundred eleven persons with presenting visual impairment in either eye due to cataract were enrolled at a tertiary eye hospital. Participants underwent a comprehensive eye examination and a WTP interview for both surgery and service provided by a senior surgeon. Demographic information, socioeconomic status and clinical data were recorded.

Results

Among 211 (98% response rate) persons completing the interview, 53.6% were women and 80.6% were retired. About 72.2% had a monthly income lower than 1000 renminbi (US $161). A total of 189 (89.6%) were willing to pay for cataract and the median amount of WTP was 6000 renminbi (US$968). And 102 (50.7%) were willing to pay additional fees for surgery performed by a senior surgeon, and the median amount of WTP was 500 renminbi (US$81). In regression models adjusting for age and gender, persons with preexisting eye diseases other than cataract, were more likely to pay for cataract surgery and service provided by a senior surgeon (P = 0.04 for both).

Conclusions

In urban China, cataract patients, especially those with preexisting eye conditions, are willing to pay additional fees for a senior surgeon. Moving to a system where the price of cataract surgery is proportional to the consultant’ skill and expertise is possible and may have a potential impact on waiting list and quality of eye care. Further studies are needed to examine the impact of such pricing system on attitudes and choices of cataract patients.     

Composite Measures of Individual and Area-Level Socio-Economic Status Are Associated with Visual Impairment in Singapore

Purpose

To investigate the independent relationship of individual- and area-level socio-economic status (SES) with the presence and severity of visual impairment (VI) in an Asian population.

Methods

Cross-sectional data from 9993 Chinese, Malay and Indian adults aged 40–80 years who participated in the Singapore Epidemiology of eye Diseases (2004–2011) in Singapore. Based on the presenting visual acuity (PVA) in the better-seeing eye, VI was categorized into normal vision (logMAR≤0.30), low vision (logMAR>0.30<1.00), and blindness (logMAR≥1.00). Any VI was defined as low vision/blindness in the PVA of better-seeing eye. Individual-level low-SES was defined as a composite of primary-level education, monthly income<2000 SGD and residing in 1 or 2-room public apartment. An area-level SES was assessed using a socio-economic disadvantage index (SEDI), created using 12 variables from the 2010 Singapore census. A high SEDI score indicates a relatively poor SES. Associations between SES measures and presence and severity of VI were examined using multi-level, mixed-effects logistic and multinomial regression models.

Results

The age-adjusted prevalence of any VI was 19.62% (low vision = 19%, blindness = 0.62%). Both individual- and area-level SES were positively associated with any VI and low vision after adjusting for confounders. The odds ratio (95% confidence interval) of any VI was 2.11(1.88–2.37) for low-SES and 1.07(1.02–1.13) per 1 standard deviation increase in SEDI. When stratified by unilateral/bilateral categories, while low SES showed significant associations with all categories, SEDI showed a significant association with bilateral low vision only. The association between low SES and any VI remained significant among all age, gender and ethnic sub-groups. Although a consistent positive association was observed between area-level SEDI and any VI, the associations were significant among participants aged 40–65 years and male.

Conclusion

In this community-based sample of Asian adults, both individual- and area-level SES were independently associated with the presence and severity of VI.     

Insights into substrate gating in H. influenzae rhomboid

Rhomboids are a remarkable class of serine proteases that are embedded in lipid membranes. These membrane-bound enzymes play key roles in cellular signaling events, and disruptions in these events can result in numerous disease pathologies, including hereditary blindness, type 2 diabetes, Parkinson's disease, and epithelial cancers. Recent crystal structures of rhomboids from Escherichia coli have focused on how membrane-bound substrates gain access to a buried active site. In E. coli, it has been shown that movements of loop 5, with smaller movements in helix 5 and loop 4, act as substrate gate, facilitating inhibitor access to rhomboid catalytic residues. Herein we present a new structure of the Haemophilus influenzae rhomboid hiGlpG, which reveals disorder in loop 5, helix 5, and loop 4, indicating that, together, they represent mobile elements of the substrate gate. Substrate cleavage assays by hiGlpG with amino acid substitutions in these mobile regions demonstrate that the flexibilities of both loop 5 and helix 5 are important for access of the substrates to the catalytic residues. Mutagenesis indicates that less mobility by loop 4 is required for substrate cleavage. A reexamination of the reaction mechanism of rhomboid substrates, whereby cleavage of the scissile bond occurs on the si-face of the peptide bond, is discussed.     

Both STING and MAVS Fish Orthologs Contribute to the Induction of Interferon Mediated by RIG-I

Viral infections are detected in most cases by the host innate immune system through pattern-recognition receptors (PRR), the sensors for pathogen-associated molecular patterns (PAMPs), which induce the production of cytokines, such as type I interferons (IFN). Recent identification in mammalian and teleost fish of cytoplasmic viral RNA sensors, RIG-I-like receptors (RLRs), and their mitochondrial adaptor: the mitochondrial antiviral signaling (MAVS) protein, also called IPS-1, highlight their important role in the induction of IFN at the early stage of a virus infection. More recently, an endoplasmic reticulum (ER) adaptor: the stimulator of interferon genes (STING) protein, also called MITA, ERIS and MPYS, has been shown to play a pivotal role in response to both non-self-cytosolic RNA and dsDNA. In this study, we cloned STING cDNAs from zebrafish and showed that it was an ortholog to mammalian STING. We demonstrated that overexpression of this ER protein in fish cells led to a constitutive induction of IFN and interferon-stimulated genes (ISGs). STING-overexpressing cells were almost fully protected against RNA virus infection with a strong inhibition of both DNA and RNA virus replication. In addition, we found that together with MAVS, STING was an important player in the RIG-I IFN-inducing pathway. This report provides the demonstration that teleost fish possess a functional RLR pathway in which MAVS and STING are downstream signaling molecules of RIG-I. The Sequences presented in this article have been submitted to GenBank under accession numbers: Zebrafish STING ({"type":"entrez-nucleotide","attrs":{"text":"HE856619","term_id":"410810118","term_text":"HE856619"}}HE856619); EPC STING ({"type":"entrez-nucleotide","attrs":{"text":"HE856620","term_id":"410810120","term_text":"HE856620"}}HE856620); EPC IRF3 ({"type":"entrez-nucleotide","attrs":{"text":"HE856621","term_id":"410810122","term_text":"HE856621"}}HE856621); EPC IFN promoter ({"type":"entrez-nucleotide","attrs":{"text":"HE856618","term_id":"410810117","term_text":"HE856618"}}HE856618).     

Differential interleukin-2 and interferon-gamma production by human lymphocyte cultures exceptionally resistant to Epstein-Barr virus immortalization

Epstein-Barr virus (EBV) readily immortalizes human peripheral blood lymphocytes (PBL) in vitro. However, during the past several years, we found that PBL from two exceptional EBV-seropositive healthy adult individuals were refractory to immortalization by EBV. We report here a study aimed at learning about the immunobiological features which differentiate these EBV-resistant (R) PBL from others which are susceptible (S) to EBV immortalization. Results of this investigation indicate that: (a) Following EBV infection, R-PBL produced significantly higher amounts of interferon gamma (IFN-gamma) than S-PBL. There were however no differences in regard to interferon alpha production between these two types (R and S) of EBV-infected cultures. (b) R-PBL had a maximal interleukin-2 (IL-2) production by S-PBL occurred at least 48 hr later, i.e., at Day 7. (c) The percentage of non-B cells expressing the IL-2 receptor was also higher in EBV-infected R-PBL than S-PBL. (d) In contrast, expression of IL-2 receptors after EBV infection was higher on B cells from S-PBL than on B cells from R-PBL. Interestingly, no differences were noted in regard to IL-2 receptor expression between R-PBL and S-PBL treated with mitogens (i.e., phytohemagglutinin and pokeweed mitogen). (e) Finally, using anti-IL-2 and anti-IFN-gamma antibodies in EBV-infected R-PBL cultures, we were able to obtain EBV-induced immortalization of these cultures. Taken together, these results suggest that an early IL-2 synthesis and high IFN-gamma production by EBV-infected PBL play an important role against lymphocyte immortalization by EBV.     

Refractive spherules in phloem ofMicrosorium scolopendria andPsilotum nudum

Summary Phloem tissues ofMicrosorium scolopendria (Polypodiaceae) andPsilotum nudum (Psilotaceae) were examined with light and electron microscopes. The characteristic refractive spherules in the sieve elements ofM. scolopendria apparently develop from endoplasmic reticulum-derived cytoplasmic vesicles. In both taxa they have not been observed to be spatially related to plastids or mitochondria. Refractive spherules contain protein and often occur in the peripheral cytoplasm of mature sieve elements. InM. scolopendria they also occur in pericycle cells. Significant differences in refractive spherule substructure occur between the two taxa studied.     

Inhibition by serum of encephalitogenic activity of myelin basic protein: nature of the serum factor responsible.

The capacity of basic protein of myelin (BPM) from various species to produce experimental autoimmune encephalomyelitis (EAE) in the guinea pig or the Lewis rat, was abrogated by mixing BPM with alpha₂ macroglobulin, transferrin, and ceruloplasmin. Inhibition of EAE was observed only when the encephalitogen was held in vitro directly with the inhibitor and not when each was injected separately. Guinea pigs which failed to develop EAE after an injection of a mixture of BPM with alpha₂ macroglobulin nevertheless developed cell-mediated immunity and antibodies to BPM. However, animals injected with a mixture of the encephalitogenic tryptophan peptide of BPM with alpha₂ macroglobulin developed neither cell-mediated immunity nor humoral antibody to BPM. Inhibition of EAE in the present studies was attributed to binding between the inhibitor and BPM, which possibly blocked its main encephalitogenic determinant, rather than enzymatic cleavage of BPM. This inhibitory effect of alpha globulin on immunogenicity could represent a further example of homeostatic control over immune responses.