Oxidation pretreatment by calcium hypochlorite to improve the sensitivity of enzyme inhibition-based detection of organophosphorus pesticides.

BACKGROUND: Enzyme inhibition-based detection is the most widely used method for rapid detection of organophosphorus pesticides (OPs) in food and agricultural products. However, the accuracy of the method is negatively affected by low inhibitory activities of OPs with PS moiety on acetylcholinesterase. RESULTS: We demonstrated that oxidation pretreatments with bromine, hydrogen peroxide, or calcium hypochlorite significantly enhanced the enzyme inhibitory activities of these OPs. Especially, calcium hypochlorite (0.05%) pretreatment converted the PS moiety in OPs to PO and produced the most potent and steady inhibitory effect on the enzyme. This, in turn, resulted in a dramatic increase in the sensitivity of enzyme inhibition-based detection of these OPs by as much as 2 to 7 orders of magnitude. Importantly, this enhanced detection of OPs was validated in various vegetable samples. CONCLUSION: Our findings provide a solid basis to use calcium hypochlorite pretreatment for the improved detection of OPs by the enzyme inhibition-based method. © 2017 Society of Chemical Industry.

Distribution of multiple chalazia in eyelids of pediatrics requiring surgery in southeast China: a hospital-based cross-sectional study.

Background: Multiple chalazia are common in children, and many are treated by surgery. However, the distribution of different types of multiple chalazia has not been studied. This research aimed to investigate the location and number of multiple chalazia in pediatrics who need surgical treatments. Methods: Patients with multiple chalazia treated by incision and curettage surgery (I&C) in a tertiary children's hospital between June and December 2016 were reviewed. Demographic data, locations, and numbers of chalazia were recorded. Data were analyzed using generalized linear models of the counts and the occurrences of chalazia. Hypotheses were tested using likelihood ratio tests appropriate for each type of data. Results: The study included 128 subjects, most of which were 1-3 years old. The majority of patients had bilateral chalazia (95.3%), and the proportions of patients with internal, external, and marginal chalazion differed dramatically (99.2%, 61.7%, and 2.3%, respectively). The number of internal and external chalazia did not vary significantly with gender, age, or residence of the patients. Internal chalazia were located more frequently in the upper lids (p<0.001). External chalazia showed no preference of localization. The average number of internal chalazia in each eyelid did not relate to the presence of external chalazia. Conclusions: Multiple chalazia are common among younger children in southeast China. The anatomical distribution varies depending on the type of chalazion. Multiple chalazia often occur bilaterally and internally. If doctors are more aware of the anatomical distribution of chalazia, this might result in a higher success rate of I&C.

Identification of a novel frameshift mutation in PITX2 gene in a Chinese family with Axenfeld-Rieger syndrome.

OBJECTIVE: Axenfeld-Rieger syndrome (ARS) is phenotypically and genetically heterogeneous. In this study, we identified the underlying genetic defect in a Chinese family with ARS. METHODS: A detailed family history and clinical data were recorded. The ocular phenotype was documented using slit-lamp photography and systemic anomalies were also documented where available. The genomic DNA was extracted from peripheral blood leukocytes. All coding exons and intron-exon junctions of paired-like homeodomain transcription factor 2 (PITX2) gene and the forkhead box C1 (FOXC1) gene were amplified by polymerase chain reaction (PCR) and screened for mutation by direct DNA sequencing. Variations detected in exon 5 of PITX2 were further evaluated with cloning sequencing. The exon 5 of PITX2 was also sequenced in 100 healthy controls, unrelated to the family, for comparison. Structural models of the wild type and mutant homeodomain of PITX2 were investigated by SWISS-MODEL. RESULTS: Affected individuals exhibited variable ocular phenotypes, whereas the systemic anomalies were similar. After direct sequencing and cloning sequencing, a heterozygous deletion/insertion mutation c.198_201delinsTTTCT (p.M66Ifs*133) was revealed in exon 5 of PITX2. This mutation co-segregated with all affected individuals in the family and was not found either in unaffected family members or in 100 unrelated controls. CONCLUSIONS: We detected a novel frameshift mutation p.M66Ifs*133 in PITX2 in a Chinese family with ARS. Although PITX2 mutations and polymorphisms have been reported from various ethnic groups, we report for the first time the identification of a novel deletion/insertion mutation that causes frameshift mutation in the homeodomain of PITX2 protein.

Ocular findings in syndromic gingival fibromatosis: a case study and electronic microscopic investigation of lens.

We report a case of syndromic gingival fibromatosis with notable ocular lesions, bilateral congenital cataracts, esotropia, and high myopia of a 21-year-old male patient from China. The patient was diagnosed with gingival fibromatosis based on his massive gingival overgrowth and histological findings that were consistent with gingival fibromatosis through a gingival biopsy. Lens opacity features were presented and phacoemulsificaion with intraocular lens(IOL) implantation was performed to manage the cataracts in both eyes. Transmission electronic microscopy was used to investigate the ultrastructure of the removed lens tissue. We also review the literature on gingival fibromatosis and briefly summarize the ocular manifestations of this rare disease.

A novel p.R890C mutation in EPHA2 gene associated with progressive childhood posterior cataract in a Chinese family.

AIM: To identify the genetic defect in a Chinese family with bilateral progressive childhood posterior cataract. METHODS: A two-generation family was recruited in this study. Family history and clinical data were recorded. All reported candidate genes associated with congenital posterior cataract were screened by direct DNA sequencing. RESULTS: All affected individuals presented posterior opacities in the lens. Direct sequencing of the candidate genes showed a heterozygous c. 2668C>T variation in EPHA2 gene, which resulted in the replacement of arginine by cysteine at codon 890 (p. R890C). This mutation was found in two affected individuals, but was not observed in 200 normal controls. CONCLUSION: We report a novel mutation (p. R890C) in the EPHA2 receptor tyrosine kinase gene. The finding expands the mutation spectrum of EPHA2 in association with posterior cataract.

Chinese family with atypical granular corneal dystrophy type I caused by the typical R555W mutation in TGFBI.

AIM: To investigate the clinical features and genetic defects in four generations of a Chinese family affected with atypical granular corneal dystrophy type I (GCD type I). METHODS: Family history and clinical data were recorded. Genomic DNA samples were obtained from peripheral blood leukocytes of all participated. Exons of the transforming growth factor-ß-induced (TGFBI) gene were directly sequenced after being amplified by polymerase chain reaction (PCR), and multi-point linkage analysis using microsatellite makers flanking the gene was applied to identify the disease-causing mutation. RESULTS: Clinical features were quite variable in patients, some patients only had opacities in the epithelium, and others revealed multiple bilateral circular, discrete, crumb-like opacities mainly in the epithelium, with several in different depths of corneal stroma, and the performance was different bilaterally, even in the same patient. Directly nucleotide sequencing revealed a heterozygous p.R555W mutation in the coding sequence of the TGFBI gene in all affected individuals of the family, but was not found in all unaffected. The maximum logarithm of odds (LOD) score obtained by multi-point analysis was detected at marker locus D5S393 (LOD=2.740; α=1.000). CONCLUSION: Our case presented with clinical futures and the pathogenic mutations in TGFBI gene, the phenotype of the pedigree was quite different from typical GCD type I, so we suggested that this phenotype was a variant of GCD type I. These findings expand the knowledge about GCD type I, and demonstrate that molecular genetic analysis is important to make an accurate diagnosis of patients with variable corneal dystrophies in clinic.

Electron microscopic investigation of anterior lens capsule in an individual with true exfoliation.

AIM: To determine the changes which occur in the anterior capsule in true exfoliation which is a very rare condition. METHODS: The anterior capsule from a 93 year-old patient and 6 other patients with age-related cataract during capsulorhexis was examined via transmission electron microscopy (TEM). RESULTS: TEM revealed apoptosis of lens epithelial cells in both two groups. Moreover, we observed lamellar delamination, granular belts in the anterior capsular zone and loss of the subcapsular epithelium cells in the posterior capsular zone, as well as abnormal fibrils located in the central capsular layer only in the sample from the patient with true exfoliation. CONCLUSION: We suggest that loss of lens epithelial cells and appearance of abnormal fibrils is important in disease developing, and our study supported age-related degeneration is one of causative factors in true exfoliation.

Novel mutation c.980_983delATTA compound with c.986C>A mutation of the FRMD7 gene in a Chinese family with X-linked idiopathic congenital nystagmus.

OBJECTIVE: To screen mutations in FERM domain-containing protein 7 (FRMD7) gene in two Chinese families with X-linked idiopathic congenital nystagmus (XLICN). METHODS: Common ophthalmic data and peripheral blood of two Chinese XLICN families (families A and B) were collected after informed consent. Genomic DNA was prepared from the peripheral blood of members of the two families and from 100 normal controls. Mutations in the FRMD7 gene were determined by directly sequencing polymerase chain reaction (PCR) products. RESULTS: We identified a novel mutation c.980_983delATTA compound with c.986C>A mutation in the 11th exon of FRMD7 in family B, and a previously reported splicing mutation c.781C>G (p.R261G) [corrected] in family A. The mutations were detected in patients and female carriers, while they were absent in other relatives or in the 100 normal controls. CONCLUSIONS: Our results expand the spectrum of FRMD7 mutations in association with XLICN, and further confirm that the mutations of FRMD7 are the underlying molecular mechanism for XLICN.