The evolution of hot Jupiters revealed by the age distribution of their host stars.

The unexpected discovery of hot Jupiters challenged the classical theory of planet formation inspired by our solar system. Until now, the origin and evolution of hot Jupiters are still uncertain. Determining their age distribution and temporal evolution can provide more clues into the mechanism of their formation and subsequent evolution. Using a sample of 383 giant planets around Sun-like stars collected from the kinematic catalogs of the Planets Across Space and Time project, we find that hot Jupiters are preferentially hosted by relatively younger stars in the Galactic thin disk. We subsequently find that the frequency of hot Jupiters declines with age as [Formula: see text]. In contrast, the frequency of warm/cold Jupiters shows no significant dependence on age. Such a trend is expected from the tidal evolution of hot Jupiters' orbits, and our result offers supporting evidence using a large sample. We also perform a joint analysis on the planet frequencies in the stellar age-metallicity plane. The result suggests that the frequencies of hot Jupiters and warm/cold Jupiters, after removing the age dependence are both correlated with stellar metallicities as [Formula: see text] and [Formula: see text], respectively. Moreover, we show that the above correlations can explain the bulk of the discrepancy in hot Jupiter frequencies inferred from the transit and radial velocity (RV) surveys, given that RV targets tend to be more metal-rich and younger than transits.

LAMOST telescope reveals that Neptunian cousins of hot Jupiters are mostly single offspring of stars that are rich in heavy elements.

We discover a population of short-period, Neptune-size planets sharing key similarities with hot Jupiters: both populations are preferentially hosted by metal-rich stars, and both are preferentially found in Kepler systems with single-transiting planets. We use accurate Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) Data Release 4 (DR4) stellar parameters for main-sequence stars to study the distributions of short-period [Formula: see text] Kepler planets as a function of host star metallicity. The radius distribution of planets around metal-rich stars is more "puffed up" compared with that around metal-poor hosts. In two period-radius regimes, planets preferentially reside around metal-rich stars, while there are hardly any planets around metal-poor stars. One is the well-known hot Jupiters, and the other one is a population of Neptune-size planets ([Formula: see text]), dubbed "Hoptunes." Also like hot Jupiters, Hoptunes occur more frequently in systems with single-transiting planets although the fraction of Hoptunes occurring in multiples is larger than that of hot Jupiters. About [Formula: see text] of solar-type stars host Hoptunes, and the frequencies of Hoptunes and hot Jupiters increase with consistent trends as a function of [Fe/H]. In the planet radius distribution, hot Jupiters and Hoptunes are separated by a "valley" at approximately Saturn size (in the range of [Formula: see text]), and this "hot-Saturn valley" represents approximately an order-of-magnitude decrease in planet frequency compared with hot Jupiters and Hoptunes. The empirical "kinship" between Hoptunes and hot Jupiters suggests likely common processes (migration and/or formation) responsible for their existence.

Exoplanet orbital eccentricities derived from LAMOST-Kepler analysis.

The nearly circular (mean eccentricity [Formula: see text]) and coplanar (mean mutual inclination [Formula: see text]) orbits of the solar system planets motivated Kant and Laplace to hypothesize that planets are formed in disks, which has developed into the widely accepted theory of planet formation. The first several hundred extrasolar planets (mostly Jovian) discovered using the radial velocity (RV) technique are commonly on eccentric orbits ([Formula: see text]). This raises a fundamental question: Are the solar system and its formation special? The Kepler mission has found thousands of transiting planets dominated by sub-Neptunes, but most of their orbital eccentricities remain unknown. By using the precise spectroscopic host star parameters from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) observations, we measure the eccentricity distributions for a large (698) and homogeneous Kepler planet sample with transit duration statistics. Nearly half of the planets are in systems with single transiting planets (singles), whereas the other half are multiple transiting planets (multiples). We find an eccentricity dichotomy: on average, Kepler singles are on eccentric orbits with [Formula: see text] 0.3, whereas the multiples are on nearly circular [Formula: see text] and coplanar [Formula: see text] degree) orbits similar to those of the solar system planets. Our results are consistent with previous studies of smaller samples and individual systems. We also show that Kepler multiples and solar system objects follow a common relation [[Formula: see text](1-2)[Formula: see text]] between mean eccentricities and mutual inclinations. The prevalence of circular orbits and the common relation may imply that the solar system is not so atypical in the galaxy after all.

Correlations between Photodegradation of Bisretinoid Constituents of Retina and Dicarbonyl Adduct Deposition.

Non-enzymatic collagen cross-linking and carbonyl adduct deposition are features of Bruch's membrane aging in the eye, and disturbances in extracellular matrix turnover are considered to contribute to Bruch's membrane thickening. Because bisretinoid constituents of the lipofuscin of retinal pigment epithelial (RPE) cells are known to photodegrade to mixtures of aldehyde-bearing fragments and small dicarbonyls (glyoxal (GO) and methylglyoxal (MG)), we investigated RPE lipofuscin as a source of the reactive species that covalently modify protein side chains. Abca4(-/-) and Rdh8(-/-)/Abca4(-/-) mice that are models of accelerated bisretinoid formation were studied and pre-exposure of mice to 430 nm light enriched for dicarbonyl release by bisretinoid photodegradation. MG protein adducts were elevated in posterior eyecups of mutant mice, whereas carbonylation of an RPE-specific protein was observed in Abca4(-/-) but not in wild-type mice under the same conditions. Immunolabeling of cryostat-sectioned eyes harvested from Abca4(-/-) mice revealed that carbonyl adduct deposition in Bruch's membrane was accentuated. Cell-based assays corroborated these findings in mice. Moreover, the receptor for advanced glycation end products that recognizes MG and GO adducts and glyoxylase 1 that metabolizes MG and GO were up-regulated in Abca4(-/-) mice. Additionally, in acellular assays, peptides were cross-linked in the presence of A2E (adduct of two vitamin A aldehyde and ethanolamine) photodegradation products, and in a zymography assay, reaction of collagen IV with products of A2E photodegradation resulted in reduced cleavage by the matrix metalloproteinases MMP2 and MMP9. In conclusion, these mechanistic studies demonstrate a link between the photodegradation of RPE bisretinoid fluorophores and aging changes in underlying Bruch's membrane that can confer risk of age-related macular degeneration.

Early diagnosis of pulmonary tuberculosis using serum biomarkers.

The early diagnosis of tuberculosis (TB) remains the biggest obstacle to the global TB control, TB being the second leading cause of infectious disease death worldwide. As such, one of the pioneering investigations is made by Xu et al. (Proteomics 2015, 15, 58-67), which is of promising clinical application significance when used in clinics and in TB screening in the population. Xu et al. revealed that statistical differences among three serum proteins (S100A9, SOD3, and MMP9) exist between TB cases and other lung disease cases. The combination of the three biomarkers could give 92.5% sensitivity and 95% specificity to discriminate TB from healthy controls.

Bisretinoid degradation and the ubiquitin-proteasome system.

Bisretinoid fluorophores of retinal pigment epithelial (RPE) lipofuscin have been shown to undergo degradation in two ways, the first involving photofragmentation following photooxidation of their polyene structure and the second being enzyme-mediated and limited, thus far, to in vitro models employing horseradish peroxidase (HRP). Here we show that both of these processes impact the ubiquitin-proteasome system (UPS) of the RPE cell. By measuring the consumption of A2E and all-trans-retinal dimer by HPLC, we confirmed that both HRP-mediated and photodegradation of the compounds occurred and that in both cases the chymotrypsin-like and trypsin-like activities of the proteasome system were decreased. With HRP-mediated degradation of A2E, there was a small negative impact on cell viability that was not mitigated by elevating gluthathione in the cell.

Impairment of the ubiquitin-proteasome pathway in RPE alters the expression of inflammation related genes.

The ubiquitin-proteasome pathway (UPP) plays an important role in regulating gene expression. Retinal pigment epithelial cells (RPE) are a major source of ocular inflammatory cytokines. In this work we determined the relationship between impairment of the UPP and expression of inflammation-related factors. The UPP could be impaired by oxidative stress or chemical inhibition. Impairment of the UPP in RPE increased the expression of several inflammatory cytokines, such as IL-6 and IL-8. However, the expression of monocyte chemoattractant protein-1 (MCP-1) and complement factor H (CFH) and was reduced upon impairment of the UPP. These data suggest that impairment of the UPP in RPE may be one of the causes of retinal inflammation and abnormal functions of monocyte and the complement system during the pathogenesis of age-related macular degeneration.

Ginsenoside Rg3 attenuates neuroinflammation and hippocampal neuronal damage after traumatic brain injury in mice by inactivating the NF-kB pathway via SIRT1 activation.

This investigation examined the potential of ginsenoside Rg3 in addressing traumatic brain injury (TBI). A TBI mouse model underwent treatment with ginsenoside Rg3 and nicotinamide (NAM). Neurological and motor functions were assessed using modified neurological severity score and rotarod tests. Brain water content in mice was detected. Primary mouse microglia were exposed to lipopolysaccharide (LPS), ginsenoside Rg3, and NAM. Nissl and immunofluorescence staining were utilized to investigate hippocampal damage, and localization of P65, Iba1 and INOS in microglia. Hippocampal neurons were grown in a culture medium derived from microglia. CCK-8 and TUNEL assays were employed to evaluate the viability and apoptosis of hippocampal neurons. Proinflammatory factors and proteins were tested using ELISA, western blot and immunofluorescence staining. As a result, ginsenoside Rg3 enhanced neurological and motor functions in mice post-TBI, reduced brain water content, alleviated hippocampal neuronal neuroinflammation and damage, activated SIRT1, and deactivated the NF-kB pathway. In LPS-stimulated microglia, ginsenoside Rg3 diminished inflammation, activated SIRT1, deactivated the NF-kB pathway, and facilitated nuclear localization of P65 and co-localization of Iba1 and INOS. The effects of ginsenoside Rg3 were countered by NAM in both TBI mice and LPS-stimulated microglia. Hippocampal neurons cultured in a medium containing LPS, ginsenoside Rg3, and NAM-treated microglia showed improved viability and reduced apoptosis compared to those cultured in a medium with LPS and ginsenoside Rg3-treated microglia alone. Ginsenoside Rg3 was effective in reducing neuroinflammation and damage in hippocampal neurons following TBI by modulating the SIRT1/NF-kB pathway, suggesting its potential as a therapeutic agent for TBI.

Conbercept combined with laser photocoagulation in the treatment of diabetic macular edema and its influence on intraocular cytokines.

BACKGROUND: The prevalence of diabetes mellitus (DM) in China is high, and the base is broad. Diabetic retinopathy (DR) is a critical condition affecting the life and health of a nation and its economic development. DR is a common complication of DM. AIM: To investigate the efficacy of laser photocoagulation combined with intravitreal injection of conbercept for treating macular edema. METHODS: Overall, 130 patients with diabetic macular edema (DME) hospitalized in The Third People's Hospital of Changzhou from January 2019 to June 2022 were retrospectively included. According to the treatment plan, 130 patients with DME were categorized into an observation and a control group, with 65 patients in each group. The control group received laser photocoagulation, and the observation group received laser photocoagulation with intravitreal injection of conbercept. Observe changes in vision, cytokines in the eye and so on. RESULTS: The total efficacy rate in the observation group (93.85%) was higher than that in the control group (78.46%) (P < 0.05). In both groups, the best corrected visual acuity correction effect improved after treatment, and the observation group was superior to the control group (P < 0.05). Retinal thickness and central macular thickness improved after treatment, and the observation group was superior to the control group (P < 0.05). The levels of vascular endothelial growth factor, interleukin-6, soluble intercellular adhesion molecule-1, and basic fibroblast growth factor in both groups improved after treatment, and the observation group was superior to the control group (P < 0.05). CONCLUSION: In patients with macular edema, combining laser photocoagulation and intravitreal injections of conbercept for DME is a more effective and safer strategy to improve vision, and lower intraocular cytokine levels.

Association of rare RNF213 variants and intracranial aneurysm risk in a Chinese population.

Background: Genetic factors play important roles in the development of intracranial aneurysm (IA). Rare RNF213 variants have been identified as being susceptible to Moyamoya disease (MMD), non-MMD intracranial artery stenosis/occlusion disease, and other vascular disorders. This study aimed to investigate the association between rare RNF213 variants and the risk of IA in a Chinese population. Methods: We recruited 174 patients with IA for RNF213 target exome sequencing. Information on the control subjects was obtained from the 1,000 Genome Project and GeneSky in-house database. After prioritizing rare RNF213 variants, the filtered variants were confirmed by Sanger sequencing. Gene-based association analyses were performed to identify the association between variants and the disease using burden and variance component methods; that is, the weighted-sum statistic (WSS) and the sequence kernel association test (SKAT), respectively. The Student's t-test, Chi-squared test, and Fisher's exact test were used to compare the clinical characteristics between carriers and non-carriers of the RNF213 variants. Results: After filtering, there were 14 RNF213 variants in 18 patients with IA, which were significantly associated with the disease after the gene-based association tests [minor allele frequency (MAF) <0.01, WSS P value 5.08×10-9; SKAT P value 2.96×10-6; SKAT-O P value 3.56×10-8]. Significant difference was not obtained between the carriers and non-carriers of the RNF213 variants in terms of the clinical characteristics. Conclusions: Rare RNF213 variants were associated with sporadic IA in a Chinese population. Our findings suggest that these rare RNF213 variants might have potentially important roles in IA. However, more comprehensive studies need to be conducted to confirm this association and causality.

Lysyl oxidase family gene polymorphisms and risk of aneurysmal subarachnoid hemorrhage: a case-control study.

Background: Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating disease caused by intracranial aneurysm (IA) rupture. Lysyl oxidase (LOX) family genes (LOX-like [LOXL] 1-4) have roles in collagen cross-linking in the extracellular matrix (ECM) and may be associated with IA rupture. We aimed to explore the association between LOX polymorphisms and the risk of aSAH. Methods: This case-control study included 2 cohorts: 133 single ruptured and 115 unruptured IA patients, and 65 multiple ruptured and 71 unruptured IA patients. Genotyping of 27 single nucleotide polymorphisms (SNPs) in LOX was performed. Logistic regression analysis was performed to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) of the SNPs of LOX and the risk of aSAH. Results: LOX rs1800449 and LOXL4 rs3793692 were positively associated with the risk of single IA rupture in the recessive model (OR =5.66, 2.06; 95% CI =1.22-26.24, 1.11-3.82, respectively) and LOX rs10519694 demonstrated a protective effect on single IA rupture (dominant model: OR =0.42, 95% CI =0.21-0.83; recessive model: OR =0.16, 95% CI =0.04-0.65; additive model: OR =0.46, 95% CI =0.28-0.78). LOXL1 rs2165241, LOXL2 rs1063582, and LOXL3 rs17010021 showed risk effects on multiple IAs rupture. LOXL3 rs17010022 showed a protective effect on multiple IAs ruptures (dominant model: OR =0.41, 95% CI =0.21-0.82; additive model: OR =0.51, 95% CI =0.30-0.85). Conclusions: LOX and LOXL4 may be susceptibility genes for single IA rupture, whereas LOXL1-3 may have a role in susceptibility to multiple IAs ruptures in the Chinese population, suggesting that LOX family genes may be associated with aSAH.

Enzymatic degradation of A2E, a retinal pigment epithelial lipofuscin bisretinoid.

Some forms of blinding macular disease are associated with excessive accumulation of bisretinoid lipofuscin in retinal pigment epithelial (RPE) cells of the eye. This material is refractory to lysosomal enzyme degradation. In addition to gene and drug-based therapies, treatments that reverse the accumulation of bisretinoid would be beneficial. Thus, we have examined the feasibility of degrading the bisretinoids by delivery of exogenous enzyme. As proof of principle we report that horseradish peroxidase (HRP) can cleave the RPE bisretinoid A2E. In both cell-free and cell-based assays, A2E levels were decreased in the presence of HRP. HRP-associated cleavage products were detected by ultraperformance liquid chromatography (UPLC) coupled to electrospray ionization mass spectrometry, and the structures of the aldehyde-bearing cleavage products were elucidated by 18O-labeling and 1H NMR spectroscopy and by recording UV−vis absorbance spectra. These findings indicate that RPE bisretinoids such as A2E can be degraded by appropriate enzyme activities.

Photo-products of retinal pigment epithelial bisretinoids react with cellular thiols.

PURPOSE: Bisretinoids such as A2E that accumulate as components of the lipofuscin of retinal pigment epithelial cells are implicated in some retinal disease processes. These compounds undergo light-induced oxidation and cleavage with the latter releasing of a mixture of aldehyde-bearing fragments, including dicarbonyl methylglyoxal. We tested for the reactivity of photooxidation and photodegradation products of A2E with thiol-containing glutathione (GSH). METHODS: In cell-free assays, we measured the ability of photooxo-A2E to competitively inhibit the GSH-mediated reduction of the thiol reagent 5,5'-dithiobis-(2-nitrobenzoic acid). Cellular GSH was assayed colorimetrically. Products of GSH reduction and GSH-adducts were detected by electrospray ionization mass spectrometry (ESI-MS) and GSH and oxidized GSH (glutathione disulfide [GSSG]) were quantified from chromatographic peak areas. RESULTS: We found that GSH can donate hydrogen atoms to, and form conjugates with, photooxidized forms of the bisretinoid A2E and with its photocleavage products. Reaction with non-photooxidized A2E was not observed. Chemical reduction by GSH involved the donation of a hydrogen atom from each of two GSHs. The ratio of GSH consumed to GSSG formed was consistent with GSH being used for both reduction and adduct formation. With the aid of synthesized standards, methylglyoxal-GSH adducts were identified within mixtures of GSH and photooxidized A2E; the adducts formed noncatalytically and by glutathione-S-transferase mediation. CONCLUSIONS: Reduction and adduct formation by GSH likely limits the reactivity of bisretinoid photoproducts and may aid their elimination from the cells. These findings are significant to forms of macular degeneration associated with bisretinoid formation and maculopathy stemming from GSH synthase deficiency.

Light filtering in a retinal pigment epithelial cell culture model.

PURPOSE: We tested for protection of blue light-exposed A2E-containing retinal pigment epithelial (RPE) from damage through the implementation of polycarbonate filters containing varying levels of a pigment that absorbs short wavelength light. METHODS: Human adult RPE cells (ARPE-19) that had accumulated synthesized A2E were exposed to either a light line delivered from a tungsten halogen source (430 ± 20 nm; 8 mW/cm) or to the entire area of a 35 mm dish (1 mW/cm). Blue-light absorbing polycarbonate filters (2.5 × 4 cm) containing varying levels of short-wavelength light absorbing pigment (1.0, 1.9, 3.8, 7.5, 15, and 35 ppm) or no dye (PC) were placed in the light path. Cytotoxicity was measured by the 4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric microtiter assay (Roche Diagnostics Corporation, Indianapolis, IN) or by fluorescent staining of non-viable cells. RESULTS: When filters containing blue-light absorbing dye were placed in the light path, protection of 430 nm irradiated A2E-laden RPE was observed. The extent of protection was dependent on the concentration of the dye. By MTT assay and fluorescence labeling, statistically significant differences (p < 0.05) between irradiation in the absence of a filter and irradiation in the presence of a filter were observed. CONCLUSIONS: The series of filters tested in this work provided protection against blue light damage in a culture model.

A Rare Variant of ANK3 Is Associated With Intracranial Aneurysm.

Intracranial aneurysm (IA) is a cerebrovascular disorder in which abnormal dilation of a blood vessel results from weakening of the blood vessel wall. The aneurysm may rupture, leading to subarachnoid hemorrhage with severe outcomes. This study was conducted to identify the genetic factors involved in the etiology of IA. Whole-exome sequencing was performed in three IA-aggregate families to identify candidate variants. Further association studies of candidate variants were performed among sporadic cases and controls. Bioinformatic analysis was used to predict the functions of candidate genes and variants. Twenty variants were identified after whole-exome sequencing, among which eight were selected for replicative association studies. ANK3 c.4403G>A (p.R1468H) was significantly associated with IA (odds ratio 4.77; 95% confidence interval 1.94-11.67; p-value = 0.00019). Amino acid R1468 in ANK3 was predicted to be located in the spectrin-binding domain of ankyrin-G and may regulate the migration of vascular endothelial cells and affect cell-cell junctions. Therefore, the variation p.R1468H may cause weakening of the artery walls, thereby accelerating the formation of IA. Thus, ANK3 is a candidate gene highly related to IA.

RNF213 rare variants and cerebral arteriovenous malformation in a Chinese population.

OBJECTIVE: Cerebral arteriovenous malformation (AVM) is characterised by an abnormal tangle of arteries and veins, the rupture of which is a significant portion of the morbidity and mortality cases, especially in young populations. However, the exact risk factors and pathophysiologic mechanisms of AVM remain poorly understood. RNF213 variants have been identified as obvious susceptible factors of several cerebrovascular disorders, such as Moyamoya disease and intracranial aneurysms. Thus, this study aimed to determine whether there is an association between RNF213 rare variants and AVM. METHODS: The AVM group included 22 patients with AVM. The control group included 1007 samples from the GeneSky in-house database and 208 samples from the 1000 Genome Project of Chinese Han Population. Genomic DNA samples were extracted from the peripheral blood of the AVM patients, and targeted exome sequencing of RNF213 was performed to assess the existence of low-frequency or rare variants. Sanger sequencing was performed to validate the identified variants. Logistic regression analysis was performed to calculate the odds ratios (ORs) and 95 % confidence intervals (CIs) of the candidate variants and risk of AVM. Statistical analyses were performed using SPSS version 21.0. RESULTS: The RNF213 c.10997T>C variant (amino acid mutation p.M3666T, NM_001256071) was observed in two AVM patients after filtration. It was significantly associated with AVM in the Chinese population (ORs, 10.30 and 25.08; 95 %; CIs, 1.38-77.10 and 4.34-144.90 compared with 1000 Genome Project of Chinese Han Population and GeneSky in-house database, respectively). CONCLUSION: Rare variants of RNF213 are associated with AVM in the Chinese population, suggesting the important role of RNF213 in AVM. Further studies are needed to verify these findings.

Polymorphisms in Lysyl Oxidase Family Genes Are Associated With Intracranial Aneurysm Susceptibility in a Chinese Population.

Purpose: Intracranial aneurysms (IA) comprise a multifactorial disease with unclear physiological mechanisms. The lysyl oxidase (LOX) family genes (LOX, LOX-like 1-4) plays important roles in extracellular matrix (ECM) reconstruction and has been investigated in terms of susceptibility to IA in a few populations. We aimed to determine whether polymorphisms in LOX family genes are associated with susceptibility to IA in a Chinese population. Methods: This case-control study included 384 patients with IA and 384 healthy individuals without IA (controls). We genotyped 27 single nucleotide polymorphisms (SNPs) of LOX family genes using the Sequenom MassARRAY® platform. These SNPs were adjusted for known risk factors and then, odds ratios (OR) and 95% confidence intervals (CI) were evaluated using binary logistic regression analysis. Results: The result showed that LOX rs10519694 was associated with the risk of IA in recessive (OR, 3.88; 95% CI, 1.12-13.47) and additive (OR, 1.56; 95%CI, 1.05-2.34) models. Stratified analyses illustrated that LOX rs10519694 was associated with the risk of single IA in the recessive (OR, 3.95; 95%CI, 1.04-15.11) and additive (OR, 1.64; 95%CI, 1.04-2.56) models. The LOXL2 rs1010156 polymorphism was associated with multiple IA in the dominant model (OR, 1.92; 95%CI, 1.02-3.62). No associations were observed between SNPs of LOXL1, LOXL3, and LOXL4 and risk of IA. Conclusion: LOX and LOXL2 polymorphisms were associated with risk of single IA and multiple IA in a Chinese population, suggesting potential roles of these genes in IA. The effects of these genes on IA require further investigation.

Associations between Inflammatory Cytokine Gene Polymorphisms and Susceptibilities to Intracranial Aneurysm in Chinese Population.

Intracranial aneurysm (IA) is a complex disease caused by genetic and environmental factors. Evidence indicates that inflammation plays an important role in IA occurrence. We aimed to explore the associations between inflammatory cytokine gene polymorphisms and IA in a Chinese population. This study enrolled 768 participants of Han ethnicity, including 384 patients with IA and 384 healthy individuals. Sixteen single nucleotide polymorphisms (SNPs) of IL1, IL6, IL12, and TNF-α genes were genotyped using the Sequenom MassARRAY platform. Univariate and multivariate logistic regression analyses were used to analyze the associations. We found IL12B rs3181216 was significantly associated with IA in the recessive and additive models (OR = 0.46, 95% CI = 0.23-0.89, P = 0.022; OR = 0.74, 95% CI = 0.56-0.98, P = 0.034, respectively). TNF-α rs1799964 was associated with IA in dominant and additive models (OR = 0.67, 95% CI = 0.46-0.98, P = 0.041; OR = 0.71, 95% CI = 0.51-0.98, P = 0.034, respectively). IL1A rs17561 was associated with single IA susceptibility (dominant model: OR = 0.52, 95% CI = 0.31-0.85, P = 0.040). The IL12B rs3181216 polymorphism was associated with single IA susceptibility in the recessive model (OR = 0.41, 95% CI = 0.18-0.93, P = 0.033). The IL12B rs2195940 polymorphism was associated with multiple IAs susceptibility (dominant model: OR = 0.28, 95% CI = 0.09-0.89, P = 0.031; additive model: OR = 0.28, 95% CI = 0.09-0.90, P = 0.032). TNF-α rs1799964 was associated with multiple IAs susceptibility in the dominant model (OR = 0.54, 95% CI = 0.30-0.97, P = 0.040). No associations were found between other polymorphisms and IA susceptibility. Therefore, IL1A, IL12B, and TNF-α gene polymorphisms are associated with IA susceptibility in a Chinese population.

Phospholipid meets all-trans-retinal: the making of RPE bisretinoids.

The lipid phase of the photoreceptor outer segment membrane is essential to the photon capturing and signaling functions of rhodopsin. Rearrangement of phospholipids in the bilayer accompanies the formation of the active intermediates of rhodopsin following photon absorption. Furthermore, evidence for the formation of a condensation product between the photolyzed chromophore all-trans-retinal and phosphatidylethanolamine indicates that phospholipid may also participate in the movement of the retinoid in the membrane. The downside of these interactions is the formation of bisretinoid-phosphatidylethanolamine compounds that accumulate in retinal pigment epithelial cells with age and that are particularly abundant in some retinal disorders. The propensity of these compounds to negatively impact on the cells has been linked to the pathogenesis of some retinal disorders including juvenile onset recessive Stargardt disease and age-related macular degeneration.

Fundus autofluorescence and the bisretinoids of retina.

Imaging of the human fundus of the eye with excitation wavelengths in the visible spectrum reveals a natural autofluorescence, that in a healthy retina originates primarily from the bisretinoids that constitute the lipofuscin of retinal pigment epithelial (RPE) cells. Since the intensity and distribution of fundus autofluorescence is altered in the presence of retinal disease, we have examined the fluorescence properties of the retinal bisretinoids with a view to aiding clinical interpretations. As is also observed for fundus autofluorescence, fluorescence emission from RPE lipofuscin was generated with a wide range of exciting wavelengths; with increasing excitation wavelength, the emission maximum shifted towards longer wavelengths and spectral width was decreased. These features are consistent with fluorescence generation from a mixture of compounds. While the bisretinoids that constitute RPE lipofuscin all fluoresced with maxima that were centered around 600 nm, fluorescence intensities varied when excited at 488 nm, the excitation wavelength utilized for fundus autofuorescence imaging. For instance the fluorescence efficiency of the bisretinoid A2-dihydropyridine-phosphatidylethanolamine (A2-DHP-PE) was greater than A2E and relative to both of the latter, all-trans-retinal dimer-phosphatidylethanolamine was weakly fluorescent. On the other hand, certain photooxidized forms of the bisretinoids present in both RPE and photoreceptor cells were more strongly fluorescent than the parent compound. We also sought to evaluate whether diffuse puncta of autofluorescence observed in some retinal disorders of monogenic origin are attributable to retinoid accumulation. However, two retinoids of the visual cycle, all-trans-retinyl ester and all-trans-retinal, did not exhibit fluorescence at 488 nm excitation.