Different Phenotypes Represent Advancing Stages of ABCA4-Associated Retinopathy: A Longitudinal Study of 212 Chinese Families From a Tertiary Center

Purpose

To evaluate the nature and association of different phenotypes associated with ABCA4 mutations in Chinese.

Methods

All patients were recruited from our pediatric and genetic eye clinic. Detailed ocular phenotypes were characterized. The disease course was evaluated by long-term follow-up observation, with a focus on fundus changes. Cox regression was used to identify the factors associated with disease progression.

Results

A systematic review of genetic and clinical data for 228 patients and follow-up data for 42 patients indicated specific features in patients with two ABCA4 variants. Of 185 patients with available fundus images, 107 (57.8%) showed focal lesions restricted to the central macula without flecks. Among these 107 patients, 30 patients (28.0%) initially presented with relatively preserved visual acuity and inconspicuous performance on routine fundus screening. A pigmentary change in the posterior pole was observed in 22 of 185 patients (11.9%), and this change mimicked retinitis pigmentosa in 10 cases (45.5%). Follow-up visits and sibling comparisons demonstrated disease progression from cone-rod dystrophy, Stargardt disease, to retinitis pigmentosa. An earlier age of onset was associated with a more rapid decrease in visual acuity (P = 0.03). Patients with two truncation variants had an earlier age of onset.

Conclusion

Phenotypic variation in ABCA4-associated retinopathy may represent sequential changes in a single disease: early-stage Stargardt disease may resemble cone-rod dystrophy, whereas the presence of diffuse pigmentation in the late stage may mimic retinitis pigmentosa. Recognizing the natural progression of fundus changes, especially those visualized by wide-field fundus autofluorescence, is valuable for diagnostics and therapeutic decision-making.

Optical microfiber sensor for detection of Ni2+ ions based on ion imprinting technology

The detection of ultralow heavy metal ion concentration is highly significant for protecting human health and maintaining the stability of the ecological environment. Herein, a microfiber interferometer chemical sensor for the detection of Ni²⁺ ions was proposed and experimentally demonstrated. The microfiber sensor was coated with an ion-imprinted chitosan polymer using Ni²⁺ as the template ion. Experimental results demonstrated a high sensitivity of 0.0454 nm nM^-M for detect-ing Ni²⁺ in the range of 10 nM to 100 nM, and a limit of detection as low as 6.5 nM was achieved. The microfiber sensor was verified using two different non-template heavy ions, Cu²⁺ and Cr³⁺, and was determined to be highly selective to Ni²⁺. Furthermore, the regeneration characteristics of the sensor were experimentally assessed by three repeated adsorption-desorption cycles, and the results showed that the microfiber sensor achieved good stability without a significant loss in sensitivity. Besides, the detecting tests of Ni²⁺ in lake water and industrial sewage samples demonstrated the sensor's practical application. This proposed sensor has the advantages of simple configuration, high selectivity and sensitivity, fast response, and the ability to serve as a platform for water safety monitoring and remote sensing.

The mRNA levels of PPARα, HIF-1α, and VEGF in the liver tissues of rats with alcoholic liver disease

OBJECTIVE

To investigate the mRNA levels of peroxisome proliferator-activated receptor α (PPARα), hypoxia-inducible factor-1α (HIF-1α), and vascular endothelial growth factor (VEGF) in the liver tissues of rats with alcoholic liver disease.

METHODS

A total of 50 Wistar rats were randomly divided into a 4-week model group (n = 10), an 8-week model group (n = 10), a 12-week model group (n = 10), a 16-week model group (n = 10), and a control group (n = 10). The control group got the same volume of distilled water, and the rats in the model groups were given ethanol to establish alcoholic liver disease model. The mRNA levels of PPARα, HIF-1α, and VEGF in the rats' liver tissues, the fatty liver degree, and the inflammation degree in each group were examined and compared.

RESULTS

The liver tissues in 4 model groups showed a more worsened fatty liver degree and inflammation degree than those in control group (P < 0.05). With the extension of the modeling time, the fatty liver degree and inflammation levels were significantly increased (P < 0.05). All the model groups showed lower mRNA level of PPARα, and higher levels of HIF-1α and VEGF than the control group (P < 0.05). With the extension of the modeling time, the relative mRNA level of PPARα was decreased, while the mRNA levels of HIF-1α and VEGF increased (all P < 0.05). The fatty liver degree and inflammation level were negatively correlated with the PPARα mRNA level (r = -0.899, -0.893, P < 0.05) and positively correlated with the HIF-1α and VEGF mRNA levels (r = 0.791, 0.679, 0.744, 0.597, P < 0.05). The PPARα mRNA level was negatively correlated with HIF-1α and VEGF mRNA levels (r = -0.732, -0.681, P < 0.05).

CONCLUSION

High PPARα mRNA levels and low HIF-1α and VEGF mRNA levels in the liver tissues of rats with alcoholic liver disease may be closely related to fatty liver and inflammation reactions.

Spatiotemporal changes of CT manifestations in 110 patients with COVID-19 pneumonia

OBJECTIVE

The aim of the study was to analyze spatiotemporal changes of CT manifestations in patients with COVID-19 pneumonia.

PATIENTS AND METHODS

In this retrospective review, 110 patients with confirmed COVID-19 by RT-PCR form February 16, 2020, to March 28, 2020 were included. A total of 449 CT scans were reviewed. We analyze the type and distribution of lung abnormalities, and CT general assessment and lesion area statistics were performed. Patients were divided into mild, moderate, and severe disease based on Chinese guidelines: mild (patients with minimal symptoms, CT scans showed no pneumonia or a small area of pneumonia infection), moderate (different extent of clinical manifestations and CT scans showed multiple pneumonia infections in both lungs), severe disease (respiratory distress, CT scans lesion area exceeds 50%, and the lesion contains consolidation). The proportion of patients with mild, moderate and severe diseases was counted.

RESULTS

The CT score and the area involved reached a peak (median 10) on illness days 7-12, and then, continued to be at a high level. The main abnormal pattern after symptoms appeared GGO (36/94 [36%] to 40/65 [62%] in different periods). The proportion of mixed reached its peak on illness days 13-18 (36/93 [39%]). Pure GGO was the most common subtype of GGO (24 of 60 CT scans [40%] to 23 of 33 CT scans [70%]) after symptoms onset. The ratio of GGO with irregular lines and interfaces peaked on illness days 7-12 (6/34 [18%]). The lesions are mainly distributed on both sides and under the pleura. 76/84 (90%) of discharged patients had residual lesions on the final CT scans. 4 confirmed patients' CT scans did not show lesions (on illness days 1-24 days). There were 47 mild cases (42.7%), 46 moderate cases (41.8%), and 7 severe cases (6.3%).

CONCLUSIONS

The degree of lung abnormality on the CT of the patients reached the peak on the 7th to 12th days of the disease. CT performance changes with time have a certain regularity, which may indicate the progress and recovery of the disease. 90% of patients still observed residual lung abnormalities in CT images at the time of discharge. There were 4 confirmed cases where the CT images did not show the lesion; hence, CT cannot be used as a basis for judging COVID-19 as a single tool.

Novel variants in GUCY2D causing retinopathy and the genotype-phenotype correlation

Leber congenital amaurosis (LCA) is the most severe form of retinopathy and cone/cone-rod dystrophy (CORD) is a common form of inherited retinopathy. Variants in GUCY2D constitute the most common cause of LCA and autosomal dominant CORD (ADCORD). The purpose of this study was to reveal novel variants and document associated phenotypes of patients with GUCY2D-associated retinopathy. Fifty-two potentially pathogenic variants (PPVs), including 12 novel ones (p.Gly144_Ala164del, p.Trp154Glyfs*12, p.Leu186Pro, p.Ala207Pro, p.Ala229Asp, p.Ala353Glu, p.Trp372*, p.Arg528*, p.Arg660Pro, p.Ile682Thr, p.Trp788Cys, and c.1026 + 171_*486del), were identified in 16 families with ADCORD and 34 families with autosomal recessive LCA (ARLCA). The novel variant c.1026 + 171_*486del is a large-scale (16.3 kb) deletion involving exons 4-20 of GUCY2D, and was identified in an ARLCA family in heterozygous status mimicking a homozygous p.Trp788Cys variant. Among the detected 52 PPVs, 32 (61.5%) were missense, seven (13.5%) were splicing, six (11.5%) were nonsense, four (7.7%) were inframe indel, and three (5.8%) were frameshift deletion. The median age of examination in 27 patients with ADCORD was 21.0 years (ranges 3-54) with a median visual acuity (VA) of 0.10 (ranges 0.02-0.90). There were 48.0% of patients with macular atrophy, 86.4% with severe reduced or extinguished cone responses, 77.3% with normal or mildly reduced rod responses, and 60.9% with high myopia. Visual impairment, macular dystrophy, and cone dysfunction deteriorated with age. The median age of examination in 34 patients with ARLCA was 1.1 years (ranges 0.3-25). There were 55.9% of patients with roving nystagmus, 68.2% with VA of worse than hand motion, 59.4% with almost normal fundus, 90.6% with extinguished rod and cone responses, and 50.0% with high hyperopia. In conclusions, twelve novel PPVs in GUCY2D (including a novel large-scale deletion) were identified. Most (32/52, 61.5%) of causative GUCY2D variants were missense. Progressive development of macular atrophy, cone dysfunction, visual impairment, and myopia are four major characteristics of GUCY2D-associated ADCORD. Normal fundus, roving nystagmus, and hypermetropia in early age are common findings specific to GUCY2D-associated ARLCA. The obtained data in this study will be of value in counselling patients and designing future therapeutic approaches.

A phase Ib study of proxalutamide (GT0918) in women with androgen receptor-positive metastatic breast cancer

1019

Background: Androgen receptor (AR) is an emerging prognostic marker and therapeutic target in breast cancer. AR is expressed in 60% to 80% of breast cancers. Recent studies have shown the association between AR signaling and tumor carcinogenesis in breast cancer, suggesting AR pathway as a potential target for breast cancer treatment. However, no AR targeting therapies have been approved for treating breast cancer. GT0918 is a new chemical entity of AR antagonist with possible AR down-regulation. We had finished the phase I study and submitted the paper. Here we present a multicenter, open-label phase Ib trial assessing the safety and efficacy of GT0918 in women with AR positive metastatic breast cancer. The primary objective is to evaluate the efficacy of GT0918. The secondary objectives are to assess its safety and to explore the relevant biomarkers. Methods: This is an expansion study of a phase I dose-escalation trial. In this phase Ib study, only patients with AR positive metastatic breast cancer were enrolled. All eligibled patients would take GT0918 orally once a day, of a 28 -day cycle. After 2 cycles’ safety and tolerability assessment, patients could choose to continue their treatment until they experience disease progression, intolerable toxicities, death, or withdrew consent. The primary efficacy endpoints were 8-week disease control rate (DCR) and 16-week DCR. The secondary efficacy endpoint was progression free survival (PFS). Results: In total, 45 patients were enrolled in the study at 200mg (n = 30) and 300mg (n = 15) doses. The most common (≥10%) treatment-related adverse events (AEs) were asthenia (42.2%), aspartate aminotransferase increased (26.7%), blood cholesterol increased(17.8%), alanine aminotransferase increased (17.8%), decreased appetite (17.8%), blood triglycerides increased (13.3%), blood lactate dehydrogenase increased (13.3%), anaemia (13.3%), blood alkaline phosphatase increased (11.1%), gamma-glutamyltransferase increased (11.1%), urinary tract infection (11.1%). Grade 3/4 AEs were reported in 9 patients (20%). No treatment-related deaths occurred. The 8-week and 16-week DCR were both 22.2% (n = 10) (95% CI 10.08%, 34.37%). The median PFS was 1.8 months (95% CI 1.8, 1.9) in all patients. 12 out of 45 (26.7%) were triple negative breast cancer cases. The median PFS was 1.9 months (95% CI 1.7, 9.1), 4 out of 12 patients (33.3%) > 6 months, 2 out of 12 patients (16.7%) > 9 months. Conclusions: GT0918 has been shown to be well tolerated and may provide potential clinical benefits to AR positive metastatic breast cancer patients. This study demonstrated triple negative in AR positive patients had more benefit. Clinical trial information: NCT04103853 .

Spectrum-frequency and genotype-phenotype analysis of rhodopsin variants

Mutations in RHO are the most common cause of autosomal dominant retinitis pigmentosa. However, the pathogenicity of many RHO variants is questionable. This study was designed to investigate the genotype-phenotype correlation for RHO variants. These RHO variants were collected from the in-house exome sequencing data of 7092 probands suffering from different types of eye conditions. The variants were classified using bioinformatics tools, family segregation, and clinical phenotypes. The RHO variants were assessed using multiple online tools and a genotype-phenotype analysis based on the data collected from of ours, gnomAD, and published literature. Totally, 52 heterozygous variants of RHO were detected in the 7092 probands. Of these 52, 17 were potentially pathogenic, were present in 35 families, and comprised 15 missense variants, one inframe deletion and one nonsense variant. All the 15 missense variants were predicted to be damaging by five different online tools. The analysis of the clinical data of the patients from the 35 families revealed certain common features, of an early damage to both the rods and the cones, relatively preserved visual acuity in adulthood, and mid-peripheral tapetoretinal degeneration with pigmentation or RPE atrophy. Our data, the data from gnomAD, and the systematic review of the 246 previously reported variants suggest that approximately two-thirds of the rare missense variants and most of the truncated variants involving upstream of K296 are likely benign. This study provides a brief summary of the characteristics of the pathogenic RHO variants. It emphasizes that the systematic evaluation of these variants at the individual-gene level is crucial in the current era of clinical genetic testing even for a well-known gene such as RHO.

Distinct peripheral blood molecular signature emerges with successful tacrolimus withdrawal in kidney transplant recipients

Tacrolimus (Tac) is an effective anti-rejection agent in kidney transplantation, but its off-target effects make withdrawal desirable. Although studies indicate that Tac can be safely withdrawn in a subset of kidney transplant recipients, immune mechanisms that underlie successful vs unsuccessful Tac removal are unknown. We performed microarray analyses of peripheral blood mononuclear cells (PBMC) RNA from subjects enrolled in the Clinical Trials in Organ Transplantation-09 study in which we randomized stable kidney transplant recipients to Tac withdrawal or maintenance of standard immunosuppression beginning 6 months after transplant. Eight of 14 subjects attempted but failed withdrawal, while six developed stable graft function for ≥2 years on mycophenolate mofetil plus prednisone. Whereas failed withdrawal upregulated immune activation genes, successful Tac withdrawal was associated with a downregulatory and proapoptotic gene program enriched within T cells. Functional analyses suggested stronger donor-reactive immunity in subjects who failed withdrawal without evidence of regulatory T cell dysfunction. Together, our data from a small, but unique, patient cohort support the conclusion that successful Tac withdrawal is not simply due to absence of donor-reactive immunity but rather is associated with an active immunological process.

A Meta-Analysis of Au/Polypropionic Acid Nanoparticles Loaded with Olacetam for the Treatment of Vascular Cognitive Impairment

To systematically evaluate the efficacy and safety of oxetam in the treatment of vascular cognitive dysfunction and the feasibility of an Au/polypropionic acid Nanometer drug delivery system to provide evidence for clinical application. PubMed, Shanghai embase, Cochrane Library, CNKI, VIP information, and Wanfang database were searched from the establishment of the database to April 2018. Patients were divided into two groups according to whether they received olacetam: the experimental group and the control group. In addition, the control group was divided into the placebo control group and the positive control group according to whether the control group received a placebo or other medication treatment controls. In the control group, a meta-analysis, a publication bias assessment, and sensitivity analysis were performed with Revman 5.3 and Stata 14.0. The results of the meta-analysis showed that compared with placebo and other medications, oxiracetam significantly improved the mental status of patients, Concise Mental State Checklist score [mean difference (MD)= 5.29, P < 0.01] and Montreal Cognitive Assessment score (MD = 4.32, P < 0.01). The Barthel Index demonstrated that oxiracetam significantly improved the quality of the daily life of patients (MD = 18, P < 0.01), but there was no difference between olacetam and placebo or other medications in the rating of activities of daily living (ADLs). The total effective rate of olacetam was significantly higher than that of other treatments (P < 0.01). Compared with placebo and other medications, the safety of oxiracetam was not significantly different (P > 0.05). Based on the current clinical evidence, olacetam is more effective and safer than alternatives in the treatment of vascular cognitive dysfunction.

Is the 5-port approach necessary in laparoscopic gastrectomy? Comparison of surgical effects of reduced-port laparoscopic gastrectomy and conventional laparoscopic-assisted gastrectomy: A meta-analysis

BACKGROUND

Reduced-port surgery, in which fewer ports are used than those in conventional laparoscopic surgery, is becoming increasingly popular for various procedures. However, the application of reduced-port surgery to the gastrectomy field is still underdeveloped. The aim of this study was to use meta-analysis to address the potentially important advantages of this surgical technique.

METHODS

Embase, PubMed, and Cochrane Library databases were systematically reviewed (through October 2019) to identify studies that compared reduced-port (RPLG) and conventional laparoscopic-assisted gastrectomy (CLG) in patients with gastric carcinoma. The endpoints were postoperative time, length of in-hospital stay, blood loss, retrieved lymph nodes, postoperative complications, time to first flatus, and aesthetic outcome.

RESULTS

A total of 11 studies, which included 1743 patients (907 RPLG and 836 CLG), were ultimately included in this analysis. Better aesthetic results: were obtained with RPLG (risk ratio 1.578; 95%CI, 1.377-1.808; P = .000), although length of in-hospital stay (standard mean difference [SMD] -0.106; 95% CI, -0.222 to 0.010; P = .074), time to first flatus (SMD -0.006; 95%CI, -0.123 to 0.110; P = .913), and perioperative complications (risk ratio 0.255; 95%CI, 0.142-0.369; P = .478) were equivalent. However, operative time was significantly longer (SMD 0.301; 95%CI, 0.194-0.409; P = .00), blood loss was greater (SMD -0.31; 95%CI, -0.415 to 0.205; P = .000), and fewer lymph nodes were harvested (SMD 0.255; 95%CI, 0.142-0.369; P = .000) in the RPLG group.

CONCLUSIONS

Our meta-analysis showed that RPLG is as safe as the CLG approach and offers better aesthetic results for patients with gastric carcinoma. However, basing on current evidence, RPLG was not an efficacious surgical alternative to CLG, as operative time was significantly longer, blood loss was greater, and fewer lymph nodes were harvested in the RPLG group. Additional high-powered controlled randomized trials are required, to determine whether RPLG truly offers any advantages; these future studies should particularly focus on pain scores and aesthetic outcomes.

Research Advances in Chitosan Oligosaccharides: From Multiple Biological Activities to Clinical Applications

Chitosan oligosaccharides (COS), hydrolysed products of chitosan, are low-molecular weight polymers with a positive charge and good biocompatibility. COS have recently been reported to possess various biological activities, including hypoglycaemic, hypolipidaemic, antioxidantantioxidant, immune regulation, anti-inflammatory, antitumour, antibacterial, and tissue engineering activities, exhibiting extensive application prospects. Currently, the biological processes and mechanisms of COS are attractive topics of study, ranging from the genetic, molecular and protein levels. This article reviews the recent discoveries about COS, especially in metabolic regulation, immune function and tissue repair, providing important insights into their multiple biological activities, medical benefits, and therapeutic mechanisms.

Downregulation of Epac Reduces Fibrosis and Induces Apoptosis Through Akt Signaling in Human Keloid Fibroblasts

BACKGROUND

A keloid is a type of pathological scar often caused by abnormal tissue repair after a skin injury and is more common in genetically susceptible individuals. cAMP is a universal second messenger and regulates critical physiological processes, including calcium homeostasis, secretion, cell fate, and gene transcription, by affecting the expression of the exchange protein directly activated by cAMP (Epac). Epac has two isoforms, Epac1 (cAMP-GEF-1) and Epac2 (cAMP-GEF-II), which show varying expression levels depending on the tissue and cell type. The expression of Epac1 in keloids has not yet been investigated.

MATERIALS AND METHODS

Keloid tissue and normal dermal skin tissue were analyzed by hematoxylin and eosin staining and immunofluorescence. Primary human keloid fibroblasts (HKFs) and human normal dermal fibroblasts were studied using immunofluorescence, wound healing tests, reverse transcription polymerase chain reaction, and western blot analysis with different concentrations of the Epac1 inhibitor ESI-09.

RESULTS

Downregulation of Epac was performed using ESI-09, a specific Epac inhibitor. The proliferation and migration capacities of HKFs and human normal dermal fibroblasts showed an ESI-09 concentration-dependent decrease. Furthermore, the apoptosis rates were significantly different between fibroblasts treated with ESI-09 and control fibroblasts. In addition, the phosphorylation level of Akt was significantly decreased, indicating that ESI-09 reduces fibrosis and induces apoptosis through Akt signaling in HKFs.

CONCLUSIONS

Our results illustrate the role of Epac1 in regulating fibroblast function during keloid pathogenesis and indicate that Epac1 may be a potential therapeutic target in keloid treatment.

Knockout of E2F1 Inhibits Adipose Stem Cell Proliferation and Differentiation in Fat Transplantation by Repressing Peroxisome Proliferator-Activated Receptor Gamma Expression

Adipose-derived stem cells (ADSCs) possess pluripotent differentiation potential and self-replication ability, which is highly significant in the field of tissue engineering. Cell-assisted lipotransfer (CAL) with ADSCs benefits fat survival. In this study, we focus on the effect of transcription factor E2F1 during CAL. The wild-type (WT) ADSCs were mixed with WT adipocytes, and the E2F1^-/- ADSCs were mixed with E2F1^-/- adipocytes. Then 2 cell mixtures were inoculated on the back 2 sides of E2F1^-/- mice, respectively denoted as the WT group (WT ADSCs + WT adipose cells) and E2F1^-/- group (E2F1^-/- ADSCs + E2F1^-/- adipose cells). At week 4, the fat graft was heavier in the WT group, with less necrotic area, more survival of mature adipocytes, and more proliferating ADSCs, compared with the E2F1^-/- group. More capillaries were transformed from ADSCs in the WT group than in the E2F1^-/- group. The in vitro protein levels of peroxisome proliferator-activated receptor gamma (PPAR-γ) were higher in WT ADSCs than in E2F1^-/- ADSCs. Therefore, these findings suggest that knockout of E2F1 could affect ADSCs to inhibit the survival of fat grafts by downregulating PPAR-γ expression.

Comparative exome sequencing reveals novel candidate genes for retinitis pigmentosa

BACKGROUND

Retinitis pigmentosa (RP) is the most common form of inherited retinal degeneration, but genetic defects in nearly half of families remain unresolved. This study aims to identify novel genes associated with RP based on whole exome sequencing (WES) data from 552 probands with RP.

METHODS

Biallelic loss-of-function (LoF) variants were selected from the WES data of 552 probands with RP and compared with that of 4728 in-house controls and the gnomAD database. Expression analysis and knockout mice model or knockdown zebrafish model were performed to confirm the association of a few candidate genes with RP.

FINDINGS

Unique biallelic LoF variants in ENSA, DACT2, DDR1, and CCDC188 were identified in four probands with RP, but were absent in 4728 in-house controls and were extremely rare in the gnomAD database. The expression of ENSA was enriched in the rod outer segments of human retina, and significant reduced responses of rods and cones were detected in Ensa knockout mice compared to wild-type mice by electroretinogram. The DACT2 transcript showed the highest expression in human retina and knockdown of dact2 in zebrafish resulted in photoreceptor disc membrane disarrangement.

INTERPRETATION

This study suggests that ENSA is likely a novel gene for RP and DACT2 is a potentially candidate gene for RP. Further studies are expected to evaluate the association between mutations in the other two genes and RP. To our knowledge, mutations in these genes have not been reported to be associated with RP before.

Knockout of E2F1 enhances the polarization of M2 phenotype macrophages to accelerate the wound healing process

Wound healing is a complex process, which is classically divided into inflammation, proliferation, and remodeling phases. Macrophages play a key role in wound healing, however, whether E2F1 mediates the M1/M2 polarization during the wound healing process is not known. Skin wounds were surgically induced in E2F1^-/- mice and their WT littermates. At day 2 and day 7 post-surgery, the wounded skin tissues including 2 to 3 mm normal skin were obtained. The wounded skin tissues were used for the analyses of immunofluorescence staining (CD68, iNOS, CD206), western blotting (CD68, iNOS, CD206, PPAR-γ) and Co-immunoprecipitation (E2F1-PPAR-γ interactions). E2F1^-/- mice exhibited faster wound healing process. At day 2, the M2 macrophages were remarkably increased in the E2F1^-/- mice. Surprisingly, in the border zone of the wound, E2F1^-/- mice had also more M2 macrophages and fewer M1 macrophages at day 7 post-surgery, suggesting a certain degree of polarization amongst the M1 and M2 phenotypes. Co-IP revealed that E2F1 indeed interacted with PPAR-γ, meanwhile western blotting and RT-PCR showed higher expression of PPAR-γ in the E2F1^-/- mice as compared to that in the WT mice. Therefore, the findings suggest that wound healing process could be accelerated with enhanced M2 polarization through increased PPAR-γ expression in E2F1 knockout mice.

Force measurement in squeezed dissipative optomechanics in the presence of laser phase noise

We investigate the force measurement sensitivity in a squeezed dissipative optomechanics within the free-mass regime under the influence of shot noise (SN) from the photon number fluctuations, laser phase noise from the pump laser, thermal noise from the environment, and optical losses from outcoupling and detection inefficiencies. Generally, squeezed light could generate a reduced SN on the squeezed quadrature and an enlarged quantum backaction noise (QBA) due to the antisqueezed conjugate quadrature. With an appropriate choice of phase angle in homodyne detection, QBA is cancellable, leading to an exponentially improved measurement sensitivity for the SN-dominated regime. By now, the effects of laser phase noise that is proportional to laser power emerge. The balance between squeezed SN and phase noise can lead to an sub-SQL sensitivity at an exponentially lower input power. However, the improvement by squeezing is limited by optical losses because high sensitivity is delicate and easily destroyed by optical losses.

RPE65 mutation frequency and phenotypic variation according to exome sequencing in a tertiary centre for genetic eye diseases in China

PURPOSE

Retinoid isomerohydrolase RPE65 has received a tremendous amount of attention due to successful clinical gene therapy for Leber congenital amaurosis (LCA) cases caused by RPE65 mutations. This study aimed to evaluate the frequency of RPE65 mutations and the associated phenotypes based on exome sequencing.

METHODS

RPE65 variants were collected from exome sequencing data obtained from 2133 probands with different forms of hereditary retinal degeneration (HRD). Clinical data were collected from probands with homozygous or compound heterozygous variants in RPE65. Associated phenotypes were characterized based on clinical data.

RESULTS

Biallelic RPE65 mutations were detected in 18 families, including eight with LCA, five with early-onset retinal degeneration, four with fundus albipunctatus-like (FA-like) changes and one with high hyperopia. These cases accounted for approximately 3.0% (8/269) of LCA and 0.8% (18/2133) of HRD cases. An almost identical FA-like change was identified in seven patients from four unrelated families with RPE65 mutations. Classification of mutations suggested that FA-like changes may be associated with biallelic missense mutations in RPE65.

CONCLUSION

Fundus albipunctatus-like (FA-like) change, a common characteristic fundus sign in RPE65 biallelic mutations, was unexpected but was confirmed by the finding that affected siblings from different families exhibited similar phenotypes. These results enrich our understanding of RPE65 mutation frequencies and their associated phenotypic variants.

A rare case of association between Budd-Chiari syndrome and sea-blue histiocytosis

Budd-Chiari syndrome (BCS) is a rare disease characterized by obstruction of hepatic venous outflow tract with diversified etiologies. Sea-blue histiocytosis (SBH) is a kind of storage diseases defined by the deposition of abundant sea-blue histiocytes in various organs and can lead to hepatosplenomegaly, cirrhosis, or even liver failure. The association between BCS and SBH has never been reported before. Here, we report a patient with BCS presenting with hepatosplenomegaly, portal hypertension, and pancytopenia who was later confirmed to also have SBH.

Pathogenicity discrimination and genetic test reference for CRX variants based on genotype-phenotype analysis

The cone-rod homeobox (CRX) gene is specifically expressed in developing and mature photoreceptors and is relatively conserved, with limited polymorphisms in coding regions. Rare variants in CRX are usually considered causative for different forms of retinal degeneration, but this might be problematic based on recent data. This study aimed to classify CRX variants based on a genotype-phenotype analysis of our data and the literature. Twenty-four CRX variants, including 14 novel variants, were detected in 37 Chinese families based on exome sequencing data obtained from 4971 Chinese probands with different forms of eye diseases. After detailed phenotypic analysis and cosegregation analysis in families with CRX variants, the 24 variants could be classified into three groups: benign (six), likely benign (six), and pathogenic (12). Somatic mosaicism was identified in a family with unaffected parents (the father had a mutant allele that was detected in approximately 17% of his leukocyte DNA) and two affected sons. Furthermore, a thorough reassessment was systematically performed for all 113 heterozygous variants as well as for their associated phenotypes from our cohort and patients previously reported. Two critical findings on the pathogenicity of CRX variants were obtained based on the genotype-phenotype correlation, family segregation and ensemble predicting methods: 1) approximately half of heterozygous missense variants are likely benign, and 2) heterozygous truncating variants affecting the homeodomain are likely benign. Truncating mutations after the homeodomain are likely associated with a more severe phenotype. Although most heterozygous pathogenic variants in CRX are associated with autosomal dominant retinal degeneration, a homozygous c.268C> T (p.Arg90Trp) substitution and homozygous complete deletion of CRX have been reported to cause Leber congenital amaurosis. In conclusion, many rare missense variants and some truncating variants in CRX are likely benign, although previously, they might have been predicted to be damaging by some online tools. Evaluation of the pathogenicity of a CRX variant should consider both its nature and location. The information obtained in this study is critical in the era of routine clinical genetic test, not only for CRX but also for many other genes with many more variants. Functional studies and additional genotype-phenotype analyses are expected to confirm these associations.

Cadmium uptake by onions, lettuce and spinach in New Zealand: Implications for management to meet regulatory limits

Paired soil and plant samples collected from the main commercial growing areas for onions (Allium cepa), lettuce (Lactuca sativa) and spinach (Spinacia olearacea) in New Zealand were used to assess the influence of plant and soil factors on cadmium (Cd) uptake in these crops. Differences in Cd concentration between eight lettuce sub-types were not consistent across sites, nor were differences in Cd concentrations in three crisphead cultivars assessed at two sites. Similarly, differences in Cd concentrations between four onion cultivars were inconsistent across sites. Mean lettuce Cd concentrations in eight lettuce varieties (range 0.005-0.034 mg∙kg-1 (fresh weight, FW) were markedly lower than those in baby leaf and bunching spinach, (range 0.005-0.19 mg∙kg-1 FW). Significant regional variation was observed in Cd concentrations in one onion cultivar (mean range 0.007-0.05 mg∙kg-1 FW). Soil Cd concentration, pH and region were statistically significant predictors of onion Cd concentration, explaining low (38% for soil Cd and pH) to moderate (50% for all three parameters) percentage of the variation. Soil Cd concentration and exchangeable magnesium or total carbon were statistically significant predictors of Cd concentration in baby leaf and bunching spinach, respectively, explaining a moderate percentage (49% and 42%) of the variation in Cd concentration. Increasing pH and soil carbon may assist in minimising Cd uptake in onion and bunching spinach, respectively. The low to moderate proportion of explained variation is partly attributable to the narrow range in some measured soil properties and indicates factors other than those assessed are influencing plant uptake. This highlights a challenge in using these relationships to develop risk-based soil guideline values to support compliance with food standards. Similarly, the inconsistency in Cd concentrations in different cultivars across sites highlights the need for multi-site assessments to confirm the low Cd accumulation status of different cultivars.

[Regulation mechanism of E2F1 transcription factor on M2 macrophages in full-thickness skin defect wounds of mice]

Objective: To explore the regulatory mechanism of E2F1 transcription factor on M2 macrophages in full-thickness skin defect wounds of mice. Methods: E2F1 gene knockout heterozygotes C57BL/6 mice and wild-type C57BL/6 mice were introduced and self-reproduced. Two weeks after birth, E2F1 gene knockout homozygotes mice and wild-type mice were identified by polymerase chain reaction (PCR). Twelve identified 6-8 weeks old male E2F1 gene knockout homozygotes C57BL/6 mice and wild-type C57BL/6 mice were selected respectively according to the random number table and set as E2F1 gene knockout group and wild-type group. A full-thickness skin defect wound was made on the back of each mouse. On post injury day (PID) 2 and 7, 6 mice in each group were selected according to the random number table and sacrificed, and the wound tissue was excised. The expression of CD68 and CD206 double positive M2 macrophages was observed by immunofluorescence method, and the percentage of CD206 positive cells was calculated. The protein expression of CD206 was detected by Western blotting. The mRNA expression of arginase 1 was detected by real-time fluorescent quantitative reverse transcription PCR (RT-PCR). Wound tissue specimens of the two groups on PID 7 were obtained, and the protein and mRNA expressions of peroxisome proliferator-activated receptor gamma (PPAR-γ) were detected by Western blotting and real-time fluorescent quantitative RT-PCR respectively. The above-mentioned experiments were repeated four times. Three specimens of wound tissue of mice in wild-type group on PID 7 were obtained to detect the relationship between E2F1 and PPAR-γ by co-immunoprecipitation and Western blotting, and this experiment was repeated two times. Data were processed with unpaired t test. Results: The size of PCR products of E2F1 gene knockout homozygotes C57BL/6 mice and wild-type C57BL/6 mice were 227 and 172 bp respectively, which were the same as those of the designed DNA fragments. On PID 2 and 7, the number of CD68 and CD206 double positive M2 macrophages in the wound tissue of mice in E2F1 gene knockout group was more than that of wild-type group, and the percentages of CD206 positive cells in the wound tissue of mice in E2F1 gene knockout group were (0.234±0.032)% and (0.584±0.023)% respectively, which were significantly higher than (0.129±0.017)% and (0.282±0.071)% of wild-type group (t=3.29, 3.54, P<0.05). On PID 2 and 7, the protein expression of CD206 in the wound tissue of mice in E2F1 gene knockout group were 1.00±0.23 and 1.63±0.26 respectively, which were significantly higher than 0.43±0.06 and 0.97±0.08 of wild-type group (t=2.41, 2.45, P<0.05). On PID 2 and 7, the mRNA expressions of arginase 1 in the wound tissue of mice in E2F1 gene knockout group were 0.482±0.105 and 0.195±0.031 respectively, which were significantly higher than 0.163±0.026 and 0.108±0.017 of wild-type group (t=3.04, 2.86, P<0.05). On PID 7, the protein and mRNA expressions of PPAR-γ in the wound tissue of mice in E2F1 gene knockout group were 0.61±0.12 and 0.51±0.13 respectively, which were significantly higher than 0.20±0.04 and 0.20±0.04 of wild-type group (t=3.36, 2.86, P<0.05). On PID 7, detection of the wound tissue of mice in wild-type group showed that PPAR-γ had unidirectional effect on E2F1. Conclusions: E2F1 transcription factor affects the polarization of M2 macrophages by inhibiting the expression of PPAR-γ, thereby inhibiting the healing process of full-thickness skin defect wounds in mice.