PHOTOTROPIN1 lysine 526 functions to enhance phototropism in Arabidopsis.

MAIN CONCLUSION: After blue-light exposure, ubiquitination of PHOTOTROPIN1 lysine 526 enhances phototropic responses. Arabidopsis blue-light photoreceptor, PHOTOTROPIN1 (PHOT1) mediates a series of blue-light responses that function to optimize photosynthesis efficiency. Blue-light sensing through the N-terminal sensory domain activates the C-terminal kinase activity of PHOT1, resulting in autophosphorylation. In addition to phosphorylation, PHOT1 lysine residue 526 (Lys526), after blue-light exposure, was found to carry a double glycine attachment, indicative of a possible ubiquitination modification. The functionality of PHOT1 Lys526 was investigated by reverse genetic approaches. Arginine replacements of PHOT1 Lys526, together with Lys527, complemented phot1-5 phot2-1 double mutant with attenuated phototropic bending, while blue-light responses: leaf expansion and stomatal opening, were restored to wild type levels. Transgenic seedlings were not different in protein levels of phot1 Lys526 527Arg than the wild type control, suggesting the reduced phototropic responses was not caused by reduction in protein levels. Treating the transformants with proteosome inhibitor, MG132, did not restore phototropic sensitivity. Both transgenic protein and wild type PHOT1 also had similar dark recovery of kinase activity, suggesting that phot1 Lys526 527Arg replacement did not affect the protein stability to cause the phenotype. Together, our results indicate that blocking Lys526 ubiquitination by arginine substitution may have caused the reduced phototropic phenotype. Therefore, the putative ubiquitination on Lys526 functions to enhance PHOT1-mediated phototropism, rather than targeting PHOT1 for proteolysis.

Association between prenatal and neonatal risk factors and development of bronchiolitis in early life.

Bronchiolitis is the most common seasonal viral respiratory disorder in infants. However, risk factors for the development of bronchiolitis, particularly during pregnancy, remain unclear. Methods: A questionnaire was administered to the parents of the hospitalized infants with acute bronchiolitis to obtain information regarding patients' medical, family, and prenatal exposure history. Logistic regression with adjustment was performed to evaluate risk factors associated with bronchiolitis in the infants. Results: Among the enrolled patients, 55 (36.7%) were diagnosed as having bronchiolitis, and the majority (89%) of the patients had moderate-to-severe bronchiolitis. The bronchiolitis group had lower C-reactive protein levels than did the control group. Fewer patients in the bronchiolitis group developed fever. However, hospital stays were longer in the bronchiolitis group than in the control group. Respiratory syncytial virus was the most detected virus (23/26, 88.6%) in the bronchiolitis group. Male sex (odds ratio [OR], 5.71; 95% confidence interval [CI], 2.02-16.12; P < 0.001), antibiotic usage during pregnancy (OR, 27.2; 95% CI, 1.12-660.84; P = 0.04), and viral infection (OR, 49.3; 95% CI, 9.01-270.26; P < 0.001) during the postnatal period were significantly associated with hospitalization for acute bronchiolitis in the infants. By contrast, pet exposure during the perinatal period was significantly and negatively associated with acute bronchiolitis (OR = 0.21, 95% CI = 0.07-0.69, P < 0.01). Conclusion: Environmental exposures during pregnancy may affect respiratory health in offspring, and effective strategies should be developed to prevent bronchiolitis in early life.

Postnatal corticosteroid treatment as a risk factor for false positivity in severe combined immunodeficiency newborn screening.

From 2011, 37 children were referred to a hospital due to low levels of T cell receptor excision circles (TRECs) from newborn screening. Among them, three children were immunologically characterized and followed up to show that postnatal corticosteroid usage may be among the causes of false positivity in TRECs screening.

Increased risk of early-onset childhood systemic lupus erythematosus for children born to affected parents: A nationwide child-parent cohort study.

Objective: Children of women with systemic lupus erythematosus (SLE) are at risk for childhood-onset SLE (cSLE). This study evaluated the incidence of early-onset cSLE and associated risk factors, including concomitant maternal and paternal autoimmune diseases, for these children. Methods: A population-based cohort study was conducted using national databases including the linked information of children and parents. Children of women with SLE and those of women without SLE were identified between 2004 and 2015. The cumulative cSLE incidence was estimated using the Kaplan-Meier method. The marginal Cox model was used to calculate the hazard ratio (HR) for cSLE events. Results: A total of 4,419 singletons of women with SLE and 1,996,759 singletons of women without SLE were identified. There were 9 (0.20%) and 503 (0.03%) incident cases of early-onset cSLE for offspring of women with and without SLE, respectively (incidence rate ratio, 8.34; 95% confidence interval [CI], 3.79-15.95]. The adjusted HR of incident cSLE in children of women with SLE was 4.65 (95% CI 2.11-10.24). Other risks for cSLE included pregnancy-induced hypertension/preeclampsia/eclampsia, paternal SLE, paternal Sjögren's syndrome (SS), and maternal SS. Conclusions: This national child-parent cohort study demonstrated that children of women with SLE are at significantly higher risk for cSLE during early childhood. Moreover, paternal SLE and parental SS increase the risk of cSLE for offspring.

NOX2-Deficient Neutrophils Facilitate Joint Inflammation Through Higher Pro-Inflammatory and Weakened Immune Checkpoint Activities.

Immune-mediated arthritis is an important chronic inflammatory disease of joints causing debilitating morbidity in affected patients. The mechanisms underlying immune-mediated arthritis have been intensively investigated, however the cellular and molecular factors contributing to the joint inflammation in different redox conditions have not been clearly elucidated. Previous research showed that phagocyte-produced reactive oxygen species (ROS) plays an anti-inflammatory role in K/BxN serum-transfer arthritis and NOX2-deficient mice tend to have more severe arthritis. Although many leukocytes play critical roles in the development of immune-mediated arthritis, the role of neutrophils, which are the main producers of ROS in inflammation, is still controversial. We hence assessed the immunomodulatory function of neutrophils from arthritic joints of NOX2-deficient and wild type mice in this study. We found more neutrophils accumulation in NOX2-deficient inflamed joints. RNA-sequencing and quantitative PCR revealed significantly increased expression of acute inflammation genes including IL1b, Cxcl2, Cxcl3, Cxcl10 and Mmp3 in activated neutrophils from the inflamed joints of NOX2-deficient mice. Moreover, gene set enrichment analysis (GSEA) showed enriched gene signatures in type I and II IFN responses, IL-6-JAK-STAT3 signaling pathway and TNF-α signaling pathway via NF-κB in NOX2-deficient neutrophils. In addition, we found that NOX2-deficient neutrophils expressed lower levels of PD-L1 and were less suppressive than WT neutrophils. Moreover, treatment of PD-L1-Fc decreased cytokine expression and ameliorated the severity of inflammatory arthritis. Our results suggest that NOX2-derived ROS is critical for regulating the function and gene expression in arthritic neutrophils. Both the strong pro-inflammatory and weakened anti-inflammatory functions of neutrophils due to abnormal redox regulation may be targets of treatment for immune-mediated arthritis.

Treatment effect of posterior scleral reinforcement on controlling myopia progression: A systematic review and meta-analysis.

BACKGROUND: High myopia is a sight-threatening disease that causes axial length elongation and severe complications. Data on the benefits of posterior scleral reinforcement surgery in myopia control have been conflicting. The purpose of this study was to explore the treatment effect and complications of posterior scleral reinforcement in the treatment of myopia. METHODS: Articles were retrieved for relevant studies from inception to July 24, 2019, by PubMed, EMBASE, and Ovid. Analyses were conducted to compare the treatment effects of controlling spherical equivalent refraction and axial length elongation. The weighted mean difference and Hedges' adjusted g were used to evaluate the treatment effects, with a random-effects model. Heterogeneity was quantified using I2 statistic and explored by subgroup analysis. Publication bias was addressed by funnel plots and Egger's test. RESULTS: A total of 11 articles were included in this meta-analysis. On estimating the treatment effect, the mean differences of myopia progression and axial length changes between surgery and control groups were 0.41 diopters per year (95% CI 0.21 to 0.61; P < .001) and -0.17 mm per year (95% CI -0.22 to -0.11; P < .001). Subgroup analysis showed significant treatment effects of the single wide strip operation. Single-arm meta-analysis showed less annual axial elongation in children subgroup. These results were robust by sensitivity analysis. The incidence of some major complications in the operation group were significantly greater (5.8% vs 2.7% for myopic degeneration; 2.3% vs 1.6% for macular hemorrhage; 0.8% vs 0 for retinal detachment). CONCLUSION: Posterior scleral reinforcement may be an effective surgery on controlling myopia progression by slowing both refraction and axial length change. However, frequent surgical complications should be considered. Further well-designed studies are needed to determine the long-term safety and efficacy.

Comparison of fungal and bacterial keratitis between tropical and subtropical Taiwan: a prospective cohort study.

BACKGROUND: Fungal keratitis (FK) has been shown to be a climate-sensitive disease. The differentiation between FK from bacterial keratitis (BK) was difficult. The purpose of this study was to compare the bacteriology and mycology between tropical and subtropical Taiwan and to investigate the independent risk factors for identification of fungi from bacteria. METHODS: Two hundred ninety-seven patients with clinical suspected microbial keratitis were prospectively enrolled. A fungal to bacteria rate (FBR), the number of fungi divided by bacteria identified, was determined to estimate the prevalence of fungi and bacteria. Clinical presentation, profiles of microorganisms, and predisposing risk factors were determined. Univariate and multivariate logistic regression analysis were used to investigate the independent risk factors. RESULTS: A total of 82 fungi and 143 bacteria were laboratory confirmed. The identification rate of fungus was higher in tropical Taiwan (p = 0.010). Among the fungi and bacteria confirmed, the FBR was 0.29 (22.4% vs. 77.6%) in subtropical Taiwan, and 0.70 (41.3% vs. 58.7%) in tropical Taiwan. Samples obtained in tropical area (p = 0.019), ocular trauma (p = 0.019), and plant exposure (p = 0.003) were independent risk factors for identification of fungus from bacteria. The predominant fungus isolated from corneal scraping were Fusarium solani (25%) and Trichosporon faecale (25%) in subtropical Taiwan; in tropical Taiwan was Fusarium spp. (50%). CONCLUSIONS: The identification rate of fungus was higher in tropical Taiwan than subtropical Taiwan. Awareness of the local epidemiology is crucial for early diagnosis of fungal keratitis in tropical area.

Quantitative analysis of tissue inflammation and responses to treatment in immune dysregulation, polyendocrinopathy, enteropathy, X-linked syndrome, and review of literature.

BACKGROUND/PURPOSE: Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is a severe autoimmune disease that is caused by regulatory T cell deficiency due to FOXP3 gene mutations. The long-term outcome can be variable depending on the extent of tissue damage caused by autoimmunity and infections, the use of immunosuppressive treatment or sequela of bone marrow transplantation. METHODS: We used immunohistochemical staining to analyze cell types infiltrating the tissue of affected organs from a classic IPEX patient with a splicing mutation (c.736-2A>C) in the FOXP3 gene. Expression of transcription factors that are critical for immune responses including T-bet, GATA-3, RORγt, and FOXP3 were evaluated in various tissue samples. For objective analysis of the distribution of different cell types in tissues, we used an automated microscope-based image acquiring system to assess quantitatively the different cell types by investigating the histopathological changes in the patient's biopsy samples obtained from the intestine and the kidneys before and after treatment. RESULTS: The percentages of cells expressing the TH2-associated transcription factor GATA3 were higher in the IPEX patient before treatment than in controls, suggesting that TH2-type cells contribute to the tissue inflammation of the gut and kidneys in IPEX syndrome. Immunosuppressive treatment effectively decreased the number of effector cells in the kidneys and intestine of the IPEX patient. CONCLUSION: This study provides quantitative evidence that the inflamed intestinal and renal tissues of the IPEX patient contain TH2-type immune effector cells, which decreased in number after immunosuppressive treatment was initiated and the clinical symptoms had improved.

Characteristics and Diagnostic Yield of Pediatric Colonoscopy in Taiwan.

BACKGROUND: Colonoscopy of the lower gastrointestinal tract has diagnostic and therapeutic value. This retrospective study aimed to investigate the indications, complications, and diagnostic yield of diagnostic colonoscopy among Taiwanese children. METHODS: The application of colonoscopy performed on children aged < 18 years between 1998 and 2010 in a referral tertiary center in Southern Taiwan was reviewed. Data on age, gender, indications, complications, and colonoscopic and final diagnoses were collected and analyzed. RESULTS: One hundred and ninety-two children with 201 colonoscopies and 27 sigmoidoscopies were enrolled. The rate of successful ileocecal approach was 77.5%. The most common indication was lower gastrointestinal bleeding (LGIB; 53.5%), followed by chronic abdominal pain (20.6%), iron deficiency anemia (IDA; 11.8%), and chronic diarrhea (11.4%). There were 144 patients (75%) with a conclusive diagnosis in their first colonoscopy, including nonspecific colitis (23.4%), polyp (20.4%), and inflammatory bowel disease (8.3%). The diagnostic yields of colonoscopy according to the major indications were 77.3% in LGIB, 68.1% in chronic abdominal pain, 66.7% in IDA, and 79.2% in chronic diarrhea. Among the patients with LGIB, juvenile polyp (26.4%) was the most common etiology. There were no major procedure-related complications. CONCLUSION: LGIB is the most common indication for pediatric colonoscopy. Pediatric colonoscopy is most effective in diagnosing pediatric LGIB and chronic diarrhea.

Synthesis of oseltamivir and tamiphosphor from N-acetyl-D-glucosamine.

Using N-acetyl-D-glucosamine as a starting material, the anti-influenza drugs oseltamivir and tamiphosphor were synthesized via a pivotal intermediate of aldehyde 8. An intramolecular Horner-Wadsworth-Emmons reaction was utilized to construct the highly functionalized cyclohexene ring. The existing N-acetyl group was transformed into an azido group for the subsequent aziridination, followed by implantation of a 3-pentoxy group of the desired stereochemistry.

Development of oseltamivir phosphonate congeners as anti-influenza agents.

Oseltamivir phosphonic acid (tamiphosphor, 3a), its monoethyl ester (3c), guanidino-tamiphosphor (4a), and its monoethyl ester (4c) are potent inhibitors of influenza neuraminidases. They inhibit the replication of influenza viruses, including the oseltamivir-resistant H275Y strain, at low nanomolar to picomolar levels, and significantly protect mice from infection with lethal doses of influenza viruses when orally administered with 1 mg/kg or higher doses. These compounds are stable in simulated gastric fluid, liver microsomes, and human blood and are largely free from binding to plasma proteins. Pharmacokinetic properties of these inhibitors are thoroughly studied in dogs, rats, and mice. The absolute oral bioavailability of these compounds was lower than 12%. No conversion of monoester 4c to phosphonic acid 4a was observed in rats after intravenous administration, but partial conversion of 4c was observed with oral administration. Advanced formulation may be investigated to develop these new anti-influenza agents for better therapeutic use.

Regioselective synthesis of di-C-glycosylflavones possessing anti-inflammation activities.

Three methods are utilized to synthesize a variety of 6,8-di-C-glycosylflavones bearing identical or distinct glycosyl moieties. Some C-glycosylation compounds are found to have better anti-inflammation activities than the parent flavones. Among them, 6,8-di-C-glucosylapigenin (known as vicenin-2) shows inhibition of TNF-alpha expression and NO production with IC(50) values of 6.8 and 5.2 muM, respectively.