Non-Targeted Metabolomic Study of Fetal Growth Restriction.

We aimed to explore the differential metabolites in amniotic fluid and its cells from fetuses with fetal growth restriction (FGR). A total of 28 specimens of amniotic fluid were collected, including 18 with FGR and 10 controls. Differential metabolites in all samples were detected by chromatography-mass spectrometry. Principal component analysis (PCA) and orthogonal partial least-squares discriminant analysis (OPLS-DA) were used to analyze the differences in metabolic spectra between the FGR and control groups through multidimensional and single-dimensional statistical analysis. The KEGG database was used for metabolic pathway enrichment analysis. Both PCA and OPLS-DA models showed a clear separation trend between FGR and control groups. We identified 27 differentially expressed metabolites in the amniotic fluid supernatant of the two groups (p < 0.05), of which 14 metabolites were up-regulated in the FGR group, and 13 metabolites, such as glutamate, phenylalanine, valine and leucine, were down-regulated. We also identified 20 differentially expressed metabolites in the amniotic fluid cell (p < 0.05), of which 9 metabolites, including malic acid, glycolic acid and D-glycerate, were up-regulated significantly and 11 metabolites, including glyceraldehyde, were down-regulated. Pathway analysis showed that most of the identified differential metabolites were involved in tricarboxylic acid cycle (TCA cycle), ABC transport, amino acid metabolism pathways and so on. The results indicated that many metabolic changes associated with FGR, which are mainly manifested by abnormal metabolism of amino acid in amniotic fluid and abnormal glucose metabolism including TCA cycle in amniotic fluid cells, respectively. Our findings provide more data for exploring the mechanism of FGR and the potential therapy targets.

Identification of novel variations of oculocutaneous albinism type 2 with Prader-Willi syndrome/Angelman syndrome in two Chinese families.

Objective: Oculocutaneous albinism (OCA) is an autosomal recessive disorder caused by a variety of genomic variations. Our aim is to identify the molecular basis of OCA in two families and lay the foundation for prenatal diagnosis. Methods: Four types of OCA-causing mutations in the TYR, p, TYRP1, or SLC45A2 genes were screened. Linkage analysis was performed because the mutations found in the p gene violated the laws of classical Mendelian heredity. Primer-walking sequencing combined with microsatellite and single-nucleotide polymorphism analysis was used to ascertain deletion ranges. Bioinformatics methods were used to assess the pathogenicity of the new mutations. Results: Proband 1 was diagnosed as OCA2 with Prader-Willi syndrome (PWS) due to a novel atypical paternal deletion (chromosome 15: 22330347-26089649) and a pathogenic mutation, c.1327G>A (Val443Ile), in the p gene of the maternal chromosome. The prenatal diagnosis results for family 1 indicated the fetus was a heterozygous carrier (c.1327G>A in the p gene) with a normal phenotype. Proband 2 was diagnosed as OCA2 with Angelman syndrome (AS) due to a typical maternal deletion of chromosome 15q11-q13 and a novel mutation, c.1514T>C (Phe505Ser), in the p gene of the paternal chromosome. This novel mutation c.1514T>C (Phe505Ser) in the p gene was predicted as a pathogenic mutation. Conclusion: Our study has shown clear genotype-phenotype correlations in patients affected by distinct deletions of the PWS or AS region and missense mutations in the p gene. Our results have enriched the mutation spectrum of albinism diseases and provided insights for more accurate diagnosis and genetic counseling.

Multidimensional perspective of green financial innovation between green intellectual capital on sustainable business: the case of Pakistan.

This study investigates the multifaceted role of green innovation among green intellectual capitals (GICs) on business sustainability in Pakistan's manufacturing sector. A quantitative method based on the SEM model on SmartPLS and Stata analysis was used, which was supplemented by a survey of 800 Pakistani SME sector supply chain-associated participants. The findings revealed a significant effect of green intellectual capital and green innovation on business sustainability, while structural capital was found to have a significant moderating effect on the business sustainability of Pakistani firms. It has been determined that the relationship between GIC and BS has a strong moderation of green innovation. Furthermore, the relationship and impact of GICs on the business sustainability of Pakistani manufacturing companies were statistically significant, and green innovation played a moderating role between GIC and business sustainability. Therefore, it has been suggested that Pakistani manufacturing companies participate in eco-innovation to progress business sustainability.

Chronic cadmium exposure induces epithelial mesenchymal transition in prostate cancer cells through a TGF-ß-independent, endoplasmic reticulum stress induced pathway.

In this study, we aimed to elucidate the role of chronic cadmium (Cd) exposure in epithelial-mesenchymal transition (EMT) and thus malignant phenotypic changes of prostate cancer cells. Prostate cancer cells (PC-3 and DU145) were exposed to a non-toxic level (0.5 or 2 µM) of Cd for up to 3 months, which resulted in significantly promoted migration and invasion of the cells. These phenotypic changes were considered to be the consequence of enhanced EMT as evidenced by diminished expression of E-cadherin and increased vimentin expression. Regarding the mechanisms of Cd-induced EMT, we found Smad3 was activated but without upregulation of TGF-ß. Alternatively, we found endoplasmic reticulum (ER) stress of prostate cancer cells was significantly evoked, which was parallel with the increased reactive oxygen species (ROS). Removal of ROS by N-acetylcysteine significantly reduced ER stress in prostate cancer cells, followed by the decrease of Smad3 phosphorylation and expression of nuclear Snail, resulting in the inhibition of EMT and malignant phenotypic changes of prostate cancer cells. These findings indicated a new TGF-ß independent, ROS-mediated ER stress/Smad signaling pathway in chronic Cd exposure-induced EMT of prostate cancer cells, which could be a novel mechanism involved in cadmium-mediated cancer cells malignant transformation. Accordingly, ROS-induced ERs may become a novel preventive and therapeutic target for cancer.

Nano-designed carbon monoxide donor SMA/CORM2 exhibits protective effect against acetaminophen induced liver injury through macrophage reprograming and promoting liver regeneration.

Acetaminophen (APAP) induced liver injury is the most common drug-induced liver injury, accounting for the top cause of acute liver failure in the United State, however the therapeutic options for it is very limited. Excess generation of reactive oxygen species (ROS) and the subsequent inflammatory responses are the major factors of the liver injury. Carbon monoxide (CO) is an important gaseous molecule with versatile functions including anti-oxidation and anti-inflammation, and we previous reported the therapeutic potential of a nano-designed CO donor SMA/CORM2 in a dextran sulphate sodium (DSS) induced mouse colitis model. In this context, we investigated the effect of SMA/CORM2 in an APAP-induced mouse acute liver injury model and tackled the mechanisms involved. We found upregulation of heme oxygenase-1 (HO-1, endogenous CO generating enzyme) and the dynamic changes of macrophage polarization (pro-inflammatory M1/anti-inflammatory M2), which played important roles in the process of live injury. SMA/CORM2 treatment remarkably increased the CO levels in the liver and circulation, by which oxidative stresses in the liver were significantly reduced, and more importantly, it remarkably suppressed the expression of M1 macrophages but alternatively increased M2 polarization. Consequently the liver injury was significantly ameliorated, and the proliferation and regeneration were greatly promoted through the Pi3k/Akt/mTOR signaling pathway. The shift of macrophage polarization accompanied with the downregulated hypoxia-inducible factor-1α (HIF-1α) level. These findings suggested CO released from SMA/CORM2 manipulated the macrophage reprogramming toward M2 phenotype by inhibiting HIF-1α, which subsequently protected liver against inflammatory injury and benefited tissue repair. Moreover, compared to native CORM2, SMA/CORM2 exhibited superior bioavailability and protective effect. We thus anticipate the application of SMA/CORM2 as a therapeutic regimen for APAP induced liver injury as well as other inflammatory diseases and disorders.

Identification of a novel SUOX pathogenic variants as the cause of isolated sulfite oxidase deficiency in a Chinese pedigree.

BACKGROUND: Isolated sulfite oxidase deficiency (ISOD) is a life-threatening rare autosomal recessive disorder caused by pathogenic variants in SUOX (OMIM 606887) gene. The aim of our study was to establish a comprehensive genetic diagnosis strategy for the pathogenicity analysis of the SUOX gene within a limited time and to lay the foundation for precise genetic counseling, prenatal diagnosis, and preimplantation genetic diagnosis. METHODS: Two offspring from one set of parents were studied. Next-generation sequencing (NGS) was used to screen for disease-causing gene variants in a family with ISOD. Then, Sanger sequencing was performed to verify the presence of candidate variants. Sulfite, homocysteine and uric acid levels were detected in the patients. According to the ACMG/AMP guidelines, the pathogenicity level of novel variants was annotated. RESULTS: The nonsense pathogenic variant (c.1200C > G (p.Y400*)) and a duplication (c.1549_1574dup (p.I525 Mfs*102)) were found in the SUOX gene in the proband. The nonsense mutation (c.1200C > G (p.Y400*), pathogenic, isolated sulfite oxidase deficiency, autosomal recessive) has been reported as pathogenic and the duplication (c.1549_1574dup (p.I525 Mfs*102), pathogenic, isolated sulfite oxidase deficiency, autosomal recessive) was novel, which was classified as pathogenic according to the ACMG/AMP Standards and Guidelines. CONCLUSION: We established the pathogenicity assessment in ISOD patients based on ACMG/AMP Standards and Guidelines and this is the first ISOD patient reported in mainland China. We also discovered that ISOD is caused by SUOX gene duplication mutation, which enriches the spectrum of SUOX pathogenic variants.

The protective effect of obeticholic acid on lipopolysaccharide-induced disorder of maternal bile acid metabolism in pregnant mice.

The disorder of bile acid metabolism is a common feature during pregnancy, which leads to adverse birth outcomes and maternal damage effects. However, the cause and therapy about the disorder of bile acid metabolism are still poor. Microbial infection often occurs in pregnant women, which can induce the disorder of bile acid metabolism in adult mice. Here, this study observed the acute effect of lipopolysaccharide (LPS) on maternal bile acid of pregnant mice at gestational day 17 and the protective effect of obeticholic acid (OCA) pretreatment, a potent agonist of bile acid receptor farnesoid X receptor (FXR). The results showed LPS significantly increased the level of maternal serum and disordered bile acids components of maternal serum and liver, which were ameliorated by OCA pretreatment with obviously reducing the contents of CA, TCA, DCA, TCDCA, CDCA, GCA and TDCA in maternal serum and DCA, TCA, TDCA, TUDCA, CDCA and TCDCA in maternal liver. Furthermore, we investigated the effects of OCA on LPS-disrupted bile acid metabolism in maternal liver. LPS disrupted maternal bile acid profile by decreasing transport and metabolism with hepatic tight junctions of bile acid in pregnant mice. OCA obviously increased the protein level of nuclear FXR and regulated its target genes involving in the metabolism of bile acid, which was characterized by the lower expression of bile acid synthase CYP7A1, the higher expression of CYP3A and the higher mRNA level of transporter Mdr1a/b. This study provided the evidences that LPS disrupted bile acid metabolism in the late stage of pregnant mice and OCA pretreatment played the protective role on it by activating FXR.

Effects of Nicotinamide on Cervical Cancer-Derived Fibroblasts: Evidence for Therapeutic Potential.

PURPOSE: The present study aimed to examine the effects of nicotinamide (NAM) on cervical cancer-associated fibroblasts (CAF) for its in vitro efficacy, gross inhibition, and mechanism of inhibition. METHODS: The fibroblasts were treated with pre-specified concentrations of NAM followed by measurement of the cell proliferation using CCK-8 assay. The production of reactive oxygen species (ROS) was measured by 2',7'-Dichlorofluorescin diacetate. We further investigated the apoptosis by flow cytometry using Annexin-V. We employed JC-1 assay to detect changes in the potential of the mitochondrial membrane. We further determined the expression of apoptotic genes was measured using qRT-PCR. And lastly, cell cycle experiments were conducted to determine the influence of NAM on arresting the growth of CAF in a cell cycle. RESULTS: Our study showed that NAM was able to reduce fibroblasts viability. We specifically observed a significantly increased intracellular ROS with resultant exhaustion of cellular antioxidant defense machinery, including reduced glutathione (GSH). We further observed the involvement of mitochondrial pathway in the NAM induced apoptosis of fibroblasts. CONCLUSION: Our study supports the therapeutic potential of NAM for the treatment of cervical cancer and necessitates a further investigation of the reported findings.

Novel recessive PDZD7 biallelic mutations associated with hereditary hearing loss in a Chinese pedigree.

BACKGROUND: Autosomal recessive non-syndromic hearing loss (ARNSHL) is a highly heterogeneous genetic disease. PDZD7 is a new ARNSHL associated gene. Until now, nine PDZD7 biallelic mutation families with ARNSHL have been reported. Here we report a case of Chinese patient with ARNSHL linked to novel mutations in PDZD7 genes. METHOD: The pathogenic mutations were detected by whole exome sequencing for hereditary deafness-related genes of both the proband and his parents. We used kinship detection, mutational hazard prediction, genotype-phenotype correlation analysis and variation screening for potential pathogenic mutations. Re-sequencing was used to confirm the mutations by Sanger sequence. Real time quantitative PCR (RT-qPCR) was used to analyze the PDZD7 gene expression. Population-based screening for variation frequency, evolutionary conservation comparisons, pathogenicity evaluation, and protein structure prediction were conducted to assess the pathogenicity of the novel mutations of PDZD7 gene. RESULTS: We determined three variants of the PDZD7 gene that contributed to the deafness of the patient (PDZD7 c.192G > A, p. Met64Ile; c.1648C > T p. Gln550* and c.2341_2352delCGCAGCCGCAGCp. Arg781_Ser 784del). Pathogenic analysis in accordance with the ACMG/AMP Standards and Guidelines identified two novel mutations as Likely Pathogenic. The expression level of PDZD7 gene in the patient was decreased compared to the normal control (P < 0.001). CONCLUSION: Three mutations in PDZD7 gene linked to ARNSHL were identified in a Chinese pedigree. The findings expand not only our knowledge of genetic causes of ARNSHL, but also PDZD7 genes mutation spectrum of the disease. They will aid personalized genetic counseling, molecular diagnostics and clinical management of this condition.

Mutation analysis and pathogenicity identification of Mucopolysaccharidosis type IVA in 8 south China families.

BACKGROUND: Mucopolysaccharidosis type IVA (MPS IVA) is a rare autosomal recessive lysosomal storage disorder caused by GALNS gene mutation. The aim of our study is to detect pathogenic variants for patients suspected of MPS IVA and set the base for subsequent prenatal diagnosis and preimplantation genetic diagnosis. METHODS: In our study, 9 MPS IVA patients from south China families were investigated. Urine glycosaminoglycans (GAGS) screening was used as an initial method. For patients with abnormal result, all 14 exons and intron-exon junctions of the GALNS gene were sequenced after amplification from genomic DNA. The pathogenicity of novel mutations were analyzed with molecular genetics, bioinformatics and structure modeling in light of clinical manifestations and biochemical results. RESULTS: Among 12 mutations detected, direct sequencing found 3 novel mutations (c.686A>C, p.Y229S; c.1498G>T, p.G500C; c.278T>C, p.I93T). The pathogenicity of these novel mutations was illustrated by correlating clinical symptoms with pedigree analysis and bioinformatics analysis. CONCLUSION: The detection and variant analysis are essential for accurate diagnosis of MPS IVA patients. Our results enrich GALNS gene mutation spectrum of Chinese population. This information has important clinical value for molecular diagnosis and genetic counseling of patients with this disease.

Prevalence and Molecular Study of G6PD Deficiency in the Dai and Jingpo Ethnic Groups in the Dehong Prefecture of the Yunnan Province.

OBJECTIVES: To estimate the prevalence and mutation types of G6PD deficiency and evaluate the relationship between G6PD genotypes and erythrocyte phenotypes in the Dai and Jingpo ethnic groups in the Dehong prefecture of the Yunnan province, China. METHODS: G6PD deficiency was screened in Dai (1,530 individuals) and Jingpo (372 individuals) populations using a modified G6PD/6PGD ratio assay. Red blood cell traits were analyzed using the Sysmex XE2100 fully automated blood analyzer. PCR-direct sequencing for G6PD genotyping analysis was performed, and then the linkage disequilibrium blocks of the target SNPs were constructed with Haploview 4.2 software. RESULTS: The prevalence of G6PD deficiency was higher in the Dai ethnic group (8.63%) than in the Jingpo ethnic group (5.91%). The major mutations in descending order were rs137852314 G>A, rs72554664 G>A, rs72554665 G>T, and rs137852341 G>T. Hemoglobin concentration was significantly lower in the rs137852314 G>A group than in the normal group (p = 0.021). Mean corpuscular volume and mean corpuscular hemoglobin were substantially higher in the rs137852341 G>T group compared to the normal group (p = 0.049, p = 0.042). A linkage disequilibrium block of 13 SNPs was constructed for the G6PD deficiency group from the Dai sample. CONCLUSIONS: The Dai and Jingpo ethnic groups have distinctive incidence rates and gene frequencies of G6PD deficiency, and the genotypes of G6PD deficiency are associated with erythrocyte phenotypes.

Circular RNA circ-4099 is induced by TNF-α and regulates ECM synthesis by blocking miR-616-5p inhibition of Sox9 in intervertebral disc degeneration.

Circular RNAs (circRNAs) play important roles in the initiation and development of different diseases. Here, we detected their role in intervertebral disc (IVD) degeneration. An Arraystar human circular RNA microarray assay was used to detect circRNAs in normal and degenerated human IVD nucleus pulposus (NP) tissues. The role of circ-4099 in IVDD and its mechanism were evaluated by qRT-PCR and gain-of-function/loss-of-function studies. Interaction networks for competing endogenous RNAs (ceRNAs), miRNAs, and miRNA target gene were detected by bioinformatics analysis, RNA immunoprecipitation and luciferase assay. Expression of seventy-two circRNAs were increased by more than twofold in degenerated NP tissues. qRT-PCR showed that the expression of circ-4099 in NP tissues was consistent with that of the array screening. Over-expression of circ-4099 increased the expression of Collagen II and Aggrecan and decreased the secretion of the pro-inflammatory factors IL-1ß, TNF-α, and PGE2. TNF-α treatment increased circ-4099 expression in NP cells. NF-κB/MAPK inhibitors or shRNAs abolished the inductive effects of TNF-α on circ-4099 expression. We further demonstrated that circ-4099 was able to function as a "sponge" by competitively binding miR-616-5p, which reversed the suppression of Sox9 by miR-616-5p. We used DNA pull-down and spectrometry experiments to show that TNF-α can promote circ-4099 transcription through upregulation of GRP78. We provide the first evidence that shows circRNAs are differentially expressed in degenerated and normal NP tissues. Circ-4099 may play a role in a protective mechanism and be part of a compensatory response that maintains the synthesis and secretion of the extracellular matrix in NP cells and might be a protective factor in IVD degeneration as well as restore NP cell function.

Pathogenicity analysis of variations and prenatal diagnosis in a hereditary coagulation factor XIII deficiency family.

OBJECTIVES: Prenatal diagnosis (PND) procedure is urgent to be established for timely management and fatal consequence prevention of factor XIII deficiency (FXIIID), and variations data among Chinese are very scanty. We aimed to find a novel mutation among Chinese and establish a rapid and precise PND procedure with pathogenicity analysis to contribute to the prevention of postpartum hemorrhage in pregnant women and central nervous system bleeding in newborns. METHODS: FXIIID was diagnosed by qualitative and quantitative tests of clot solubility test and enzyme-linked immunosorbent assay, respectively. Variations were detected by direct sequencing of F13A and F13B genes in the pedigree and the unborn fetus. Pathogenicity assessment of variations was based on American College of Medical Genetics and Genomics Guidelines. RESULTS: Ten variants in the F13A gene including a novel missense mutation in exon 10, a nonsense mutation in exon 4, a missense mutation in exon 12, 2 missense mutations in exon 14, 3 polymorphisms in intron 10, 2 polymorphisms in intron 14 were detected. Two variants in the F13B gene including a polymorphism in 3'UTR and a synonymous mutation were detected. The compound heterozygous mutations of the nonsense mutation and a novel missense mutation of the F13A gene caused the deficiency in proband, and the fetus which was evaluated to be unaffected by PND was born successfully and the results were verified by follow-up visits. DISCUSSION: We first established the PND procedure with pathogenicity assessment in FXIIID patients. The F13A gene mutations' spectrum of the Chinese Han population was enriched.

Nicotinamide induces mitochondrial-mediated apoptosis through oxidative stress in human cervical cancer HeLa cells.

AIMS: Nicotinamide participates in energy metabolism and influences cellular redox status and modulates multiple pathways related with both cellular survival and death. Recent studies have shown that it induced proliferation inhibition and apoptosis in many cancer cells. However, little is known about the effects of nicotinamide on human cervical cancer cells. We aimed to evaluate the effects of the indicated concentrations nicotinamide on cell proliferation, apoptosis and redox-related parameters in HeLa cells and investigated the apoptotic mechanism. MATERIALS AND METHODS: After the treatment of the indicated concentrations nicotinamide, HeLa cell proliferation was evaluated by the CCK-8 assay and the production of ROS (reactive oxygen species) was measured using 2',7'-Dichlorofluorescin diacetate. The apoptotic effect was confirmed by observing the cellular and nuclear morphologies with fluorescence microscope and apoptotic rate of HeLa cell apoptosis was measured by flow cytometry using Annexin-V method. Moreover, we examined the mitochondrial membrane potential by JC-1 method and measured the expression of apoptosis related genes using qRT-PCR and immunoblotting. KEY FINDINGS: Nicotinamide restrained the HeLa cell proliferation and significantly increased the accumulation of ROS and depletion of GSH at relatively high concentrations. Furthermore, nicotinamide promoted HeLa cell apoptosis via the intrinsic mitochondrial apoptotic pathway. SIGNIFICANCE: Our study revealed that nicotinamide induced the apoptosis through oxidative stress and intrinsic mitochondrial apoptotic pathways in HeLa cell. The results emerge that nicotinamide may be an inexpensive, safe and promising therapeutic agent or a neoadjuvant chemotherapy for cervical cancer patients, as well useful to find new drugs for cervical cancer therapy.

Pathogenicity analysis of novel variations in Chinese Han patients with polycystic kidney disease.

OBJECTIVE: Locus and allellic heterogeneity in polycystic kidney disease (PKD) is a great challenge in precision diagnosis. We aim to establish comprehensive methods to distinguish the pathogenic mutations from the variations in PKD1, PKD2 and PKHD1 genes in a limited time and lay the foundation for precisely prenatal diagnosis, preimplantation genetic diagnosis and presymptom diagnosis of PKD. METHODS: Nested PCR combined with direct DNA sequencing were used to screen variations in PKD1, PKD2 and PKHD1 genes. The pathogenicity of de novel variations was assessed by the comprehensive methods including clinic data and literature review, databases query, analysis of co-segregation of the variants with the disease, variant frequency screening in the population, evolution conservation comparison, protein structure analysis and splice sites predictions. RESULTS: 17 novel mutations from 15 Chinese Han families were clarified including 10 mutations in PKD1 gene and 7 mutations in PKHD1 gene. The novel mutations were classified as 4 definite pathogenic, 2 highly likely pathogenic, 4 likely pathogenic, 7 indeterminate by the comprehensive analysis. The results were verified the truth by the follow-up visits. CONCLUSIONS: The comprehensive methods may be useful in distinguishing the pathogenic mutations from the variations in PKD1, PKD2 and PKHD1 genes for prenatal diagnosis and presymptom diagnosis of PKD. Our results also enriched PKD genes mutation spectrum and evolved possible genotype-phenotype correlations of Chinese Han population.

Two novel mutations in the PPIB gene cause a rare pedigree of osteogenesis imperfecta type IX.

BACKGROUND: Osteogenesis imperfecta (OI) is a rare genetic skeletal disorder characterized by increased bone fragility and vulnerability to fractures. PPIB is identified as a candidate gene for OI-IX, here we detect two pathogenic mutations in PPIB and analyze the genotype-phenotype correlation in a Chinese family with OI. METHODS: Next-generation sequencing (NGS) was used to screen the whole exome of the parents of proband. Screening of variation frequency, evolutionary conservation comparisons, pathogenicity evaluation, and protein structure prediction were conducted to assess the pathogenicity of the novel mutations. Sanger sequencing was used to confirm the candidate variants. RTQ-PCR was used to analyze the PPIB gene expression. RESULTS: All mutant genes screened out by NGS were excluded except PPIB. Two novel heterozygous PPIB mutations (father, c.25A>G; mother, c.509G>A) were identified in relation to osteogenesis imperfecta type IX. Both mutations were predicted to be pathogenic by bioinformatics analysis and RTQ-PCR analysis revealed downregulated PPIB expression in the two carriers. CONCLUSION: We report a rare pedigree with an autosomal recessive osteogenesis imperfecta type IX (OI-IX) caused by two novel PPIB mutations identified for the first time in China. The current study expands our knowledge of PPIB mutations and their associated phenotypes, and provides new information on the genetic defects associated with this disease for clinical diagnosis.

The effect and mechanism of inhibiting glucose-6-phosphate dehydrogenase activity on the proliferation of Plasmodium falciparum.

We screened >40,000 patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency and found that the G6PD Kaiping allele was under the most positive selection for fighting against malaria in the Chinese population. However, the mechanism is unknown. The current study was designed to investigate the anti-malarial effect and mechanism of G6PD deficiency. Dehydroepiandrosterone (DHEA) was utilised for inhibiting the G6PD activity of erythrocytes. Giemsa staining of blood smears and quantitative real-time PCR were used for the detection and quantification of Plasmodium falciparum infection. A transmission electron microscope was used to observe the structural changes of P. falciparum. An atomic force microscopy was used for the analyses of morphology, roughness and Young's Modulus of the infective erythrocyte membrane. When G6PD activity was inhibited by DHEA, the infection rate of P. falciparum decreased, its cell nucleus shrank, the cell organelles and metabolites were reduced gradually and the Young's Modulus of the erythrocyte membrane increased with increasing DHEA concentrations. These data indicated that Plasmodium multiplication would be inhibited in G6PD deficient erythrocytes because the Plasmodium organelles could not obtain enough nutrients, including ribose-5-phosphate and the reducing equivalent, NADPH. Moreover, the Young's Modulus of the erythrocyte membrane increased, which resulted in an increased membrane stiffness and decreased deformation. It was difficult for the merozoites to invade erythrocytes through endocytosis. Understanding these points will have a major effect on searching for new anti-malarial drug targets.

Harvesters in strawberry fields: A literature review of pesticide exposure, an observation of their work activities, and a model for exposure prediction.

Strawberry harvesters hand-pick fruit that may result in pesticide exposure from hand foliar contact. This paper included a review of publications on harvester pesticide exposure, an observation of their work activities, and development of an alternative model for pesticide exposure prediction. Previous studies monitored the dermal pesticide exposure of strawberry harvesters and found most of the exposure (>70%) was on the hands. Exposure rates (ERs) were calculated as pesticide amount on the skin per hour worked, assuming foliar contact is proportional to daily work hours. Transfer factors (TFs), used for predicting exposure, were calculated by dividing the ER by the amount of dislodgeable foliar pesticide residue. However, the ERs for harvesters working in the same field at the same time varied by as much as 10-fold, and TFs calculated from different studies varied by up to 100-fold. We tested the assumption of foliar contact time being proportional to daily work hours. We observed full work-day activities of 32 strawberry harvesters. We found that their foliar contact time per work minute differed by up to 46%. We suggested using the amount of strawberries picked to predict harvester foliar contact. For all observed harvesters, their foliar contact time per kg of strawberries picked was 35±5 s. This value was similar among harvesters with varying years of experience, of different gender, and using gloves or not. We proposed a predictive model using the amount of strawberries picked to predict harvester pesticide exposure. The exposure predicted by the model is close to the exposure measured in previous monitoring studies (R2: 0.84). The model slope is 0.33±0.03 × 103 cm2/kg. Model prediction accuracy was confirmed by monitoring captan exposure to harvesters in two fields. The model may be used as a quick screening method to estimate pesticide exposure before conducting complex human monitoring research.

Occurrence, Distribution, and Accumulation of Pesticides in Exterior Residential Areas.

Pesticides are commonly applied around residential homes, but their occurrence on exterior surfaces (e.g., pavement) has not been thoroughly evaluated. We collected 360 dust samples from curbside gutters, sidewalks, and street surfaces at 40 houses in southern California to evaluate pesticide occurrence on urban paved surfaces as well as their spatial and temporal distributions. Pesticides and select degradates were ubiquitously detected in dust, with the median concentration of total target analytes at 85 µg kg-1. A total of 75% of samples contained at least five pesticides. As a result of recurring pesticide applications, concentrations increased throughout the summer. The pyrethroids bifenthrin and permethrin accounted for 55% of total pesticides detected in the dust. The highest concentrations in dust were found on the sidewalk and in the gutter. Relative to indoor environments, human exposure risk to pesticides on paved surfaces was estimated to be lower, with the highest potential oral and dermal exposure predicted to be 38 ng day-1 for permethrin. The ubiquitous detection of pesticides on residential outdoor surfaces and the fact that the exterior concentrations did not correlate to the indoor areas highlight the necessity to measure pesticides in both indoor and outdoor areas for complete residential pesticide risk assessment.