Rapid and cost-effective molecular diagnosis using exome sequencing of one proband with autosomal dominant congenital cataract

PURPOSE

Due to high genetic heterogeneity, to exclude known mutations and map novel mutations in autosomal dominant congenital cataract (ADCC) using conventional candidate gene screening requires laborious laboratory work. We attempted to use a cost-effective exome sequencing strategy to identify disease-causing mutations in an ADCC pedigree.

METHODS

An ADCC pedigree affected by nuclear cataract and 200 unrelated senile cataract controls were recruited and given comprehensive ophthalmic examination. Whole exome of the proband of the family was captured by the Illumina TruSeq Exome Enrichment Kit, followed by sequencing using Illumina HiSeq 2000 sequencer. Validation was performed by direct sequencing.

RESULTS

The whole exome, including all exons of known ADCC disease-causing genes, was screened for possible disease-causing mutations. A recurrent missense mutation c.773C>T (p.S258F) in exon 2 of the gap junction protein alpha 8 gene (GJA8) was identified in the proband with nuclear cataract. The result was confirmed by direct sequencing. The mutation showed complete co-segregation with the disease phenotype in the family but was not observed in unrelated unaffected controls.

CONCLUSION

By successfully sequencing whole exome of only one proband and identifying a GJA8 mutation in one ADCC pedigree, the current study demonstrated that exome sequencing could serve as a rapid, robust, and cost-effective approach in clinical diagnosis and disease-causing gene discovery for ADCC.

Synthesis of carboxylic block copolymers via reversible addition fragmentation transfer polymerization for tooth erosion prevention

Dental professionals are seeing a growing population of patients with visible signs of dental erosion. The approach currently being used to address the problem typically leverages the enamel protection benefits of fluoride. In this report, an alternative new block copolymer with a hydrophilic polyacrylic acid (PAA) block and a hydrophobic poly(methyl methacrylate) (PMMA) block was developed to similarly reduce the mineral loss from enamel under acidic conditions. This series of PMMA-b-PAA block copolymers was synthesized by reversible addition fragmentation transfer (RAFT) polymerization. Their structures were characterized by gel permeation chromatography (GPC) and (1)H nuclear magnetic resonance (NMR) spectra. The molar fractions of acrylic acid (AA) in the final block copolymer were finely controlled from 0.25 to 0.94, and the molecular weight (Mn) of PMMA-b-PAA was controlled from 10 kDa to 90 kDa. The binding capability of the block copolymer with hydroxyapatite (HAP) was investigated by ultraviolet-visible spectroscopy (UV-Vis) and Fourier transform infrared (FTIR) spectroscopy. FTIR spectra confirmed that the PMMA-b-PAA block copolymer could bind to HAP via bridging bidentate bonds. Both UV-Vis and FTIR spectra additionally indicated that a high polymer concentration and low solution pH favored the polymer binding to HAP. The erosion-preventing efficacy of the PMMA-b-PAA block copolymer in inhibiting HAP mineral loss was quantitatively evaluated by atomic absorption spectroscopy (AAS). Based on the results, polymer treatment reduced the amount of calcium released by 27% to 30% in comparison with the unprotected samples. Scanning electron microscope (SEM) observations indicated that PMMA-b-PAA polymer treatment protected enamel from acid erosion. This new amphiphilic block copolymer has significant potential to be integrated into dentifrices or mouthrinses as an alternative non-fluoride ingredient to reduce tooth erosion.

Quantitative morphological analysis of curvilinear network for microscopic image based on individual fibre segmentation (IFS)

Microscopic images of curvilinear fibre network structure like cytoskeleton are traditionally analysed by qualitative observation, which can hardly provide quantitative information of their morphological properties. However, such information is crucially contributive to the understanding of important biological events, even helps to learn about the inner relations hard to perceive. Individual fibre segmentation-based curvilinear structure detector proposed in this study can identify each individual fibre in the network, as well as connections between different fibres. Quantitative information of each individual fibre, including length, orientation and position, can be extracted; so are the connecting modes in the fibre network, such as bifurcation, intersection and overlap. Distribution of fibres with different morphological properties is also presented. No manual intervening or subjective judging is required in the analysing process. Both synthesized and experimental microscopic images have verified that the detector is capable to segment curvilinear network at the subcellular level with strong noise immunity. The proposed detector is finally applied to the morphological study on cytoskeleton. It is believed that the individual fibre segmentation-based curvilinear structure detector can greatly enhance our understanding of those biological images generated from tons of biological experiments.

Identification of genes involved in regulatory mechanism of pigments in broiler chickens

Chicken is an important model organism that unites the evolutionary gap between mammals and other vertebrates and provide major source of protein from meat and eggs for all over the world population. However, specific genes underlying the regulatory mechanism of broiler pigmentation have not yet been determined. In order to better understand the genes involved in the mechanism of pigmentation in the muscle tissues of broilers, the Affymetrix microarray hybridization experiment platform was used to identify gene expression profiles at 7 weeks of age. Broilers fed canthaxanthin, natural lutein, and orangeII pigments (100 mg/kg) were used to explore gene expression profiles). Our data showed that the 7th week of age was a very important phase with regard to gene expression profiles. We identified a number of differentially expressed genes; in canthaxanthin, natural lutein, and orangeII, there were 54 (32 upregulated and 22 downregulated), 23 (15 upregulated and 8 downregulated), and 7 (5 upregulated and 2 downregulated) known genes, respectively. Our data indicate that the numbers of differentially expressed genes were more upregulated than downregulated, and several genes showed conserved signaling to previously known functions. Thus, functional characterization of differentially expressed genes revealed several categories that are involved in important biological processes, including pigmentation, growth, molecular mechanisms, fat metabolism, cell proliferation, immune response, lipid metabolism, and protein synthesis and degradation. The results of the present study demonstrate that the genes associated with canthaxanthin, natural lutein, and orangeII are key regulatory genes that control the regulatory mechanisms of pigmentation.

Reflective properties of randomly rough surfaces under large incidence angles

The reflective properties of randomly rough surfaces at large incidence angles have been reported due to their potential applications in some of the radiative heat transfer research areas. The main purpose of this work is to investigate the formation mechanism of the specular reflection peak of rough surfaces at large incidence angles. The bidirectional reflectance distribution function (BRDF) of rough aluminum surfaces with different roughnesses at different incident angles is measured by a three-axis automated scatterometer. This study used a validated and accurate computational model, the rigorous coupled-wave analysis (RCWA) method, to compare and analyze the measurement BRDF results. It is found that the RCWA results show the same trend of specular peak as the measurement. This paper mainly focuses on the relative roughness at the range of 0.16<σ/λ<5.35. As the relative roughness decreases, the specular peak enhancement dramatically increases and the scattering region significantly reduces, especially under large incidence angles. The RCWA and the Rayleigh criterion results have been compared, showing that the relative error of the total integrated scatter increases as the roughness of the surface increases at large incidence angles. In addition, the zero-order diffractive power calculated by RCWA and the reflectance calculated by Fresnel equations are compared. The comparison shows that the relative error declines sharply when the incident angle is large and the roughness is small.

Ginsenoside Rh2 promotes nonamyloidgenic cleavage of amyloid precursor protein via a cholesterol-dependent pathway

Ginsenoside Rh2 (Rh2) is a ginseng derivative used in Chinese traditional medicine. We investigated whether Rh2 can help prevent Alzheimer's disease symptoms and examined underlying mechanisms. We injected Rh2 into tg2576 Alzheimer's disease model mice and looked for behavioral improvement and senile plaque reduction in brain slices. We measured amyloid precursor protein (APP) metabolism species changes, amyloid beta40 and 42 levels and β, γ secretase activity in primary hippocampal neurons. By living cell staining, we detected surface and endocytosed APP. We also measured cholesterol and lipid rafts in primary neurons. Rh2 treatment significantly improved learning and memory performance at 14 months of age; it also reduced brain senile plaques at this age. Based on in vitro experiments, we found that Rh2 treatment increased soluble APPα (sAPPα) levels, increased CTFα/β ratios, and reduced amyloid beta 40 and 42 concentrations. Surface APP levels dramatically increased. Based on living cell staining, we found that Rh2 inhibited APP endocytosis. Based on lipid removal and reload experiments, we found that Rh2 can modulate APP by reducing cholesterol and lipid raft levels. We concluded that Rh2 improves learning and memory function in Alzheimer's disease model mice, and that this improvement is accomplished by reducing amyloid beta secretion and APP endocytosis, which in turn is achieved by reducing cholesterol and lipid raft concentrations.

Efficacy and safety of enteric-coated mycophenolate sodium in patients with de novo and maintenance renal transplantation

AIMS

To evaluate the efficacy and safety of enteric-coated mycophenolate sodium (EC-MPS) in renal transplant patients treated de novo and for maintenance.

METHODS

The efficacy and safety data of EC-MPS in renal transplant patients treated de novo and for maintenance in our hospital from July 2009 to March 2013 were reviewed.

RESULTS

Thirty-one patients treated with EC-MPS de novo were included: there were 16 male and 15 female patients. The acute allograft rejection rate was 12.9% (4/31) and pneumonia occurred in 25.8% patients (8/31); the allograft survival rate was 96.7% (30/31) with a patient survival rate of 96.7% (30/31). Gastrointestinal side effects occurred in four patients (12.9%). Only one patient discontinued EC-MPS and treatment was converted to bredinin because of gastrointestinal intolerance. Thirty-nine patients receiving mycophenolate mofetil (MMF) de novo treatment served as a control group. Five (13.2%) of 38 patients developed serious acute rejection and 10 patients (26.3%) had pulmonary infection. Eight (21.1%) patients suffered abdominal distention, diarrhoea and other gastrointestinal adverse reactions; the symptoms improved significantly after treatment change to mizoribine. Compared with the MMF de novo group, the allograft function, blood cell counts and urine protein were similar in the EC-MPS de novo treatment group. The incidence of gastrointestinal side effects was obviously lower in the EC-MPS group than in the MMF group, and there was no difference in serious acute rejection and pulmonary infection between the groups. The study also included 23 renal transplantation maintenance patients who suffered from chronic diarrhoea and treatment was changed to EC-MPS treatment. This change to EC-MPS was at 77 months after transplantation. The gastrointestinal symptoms improved significantly in 21 patients after conversion. Compared with the results at 1 week, no obvious deterioration in serum creatinine, cystatin or estimated glomerular filtration rate was found at 1, 3 and 12 months after the change. In addition, there was no marked decline in blood cell counts and no significant increase in urine protein.

CONCLUSION

The outcome of EC-MPS treatment in clinical practice of de novo kidney transplant patients was good, with high patient and graft survivals. In maintenance patients it induced an improvement in gastrointestinal side effects and a stable allograft function.

Akt and mTOR mediate programmed necrosis in neurons

Necroptosis is a newly described form of regulated necrosis that contributes to neuronal death in experimental models of stroke and brain trauma. Although much work has been done elucidating initiating mechanisms, signaling events governing necroptosis remain largely unexplored. Akt is known to inhibit apoptotic neuronal cell death. Mechanistic target of rapamycin (mTOR) is a downstream effector of Akt that controls protein synthesis. We previously reported that dual inhibition of Akt and mTOR reduced acute cell death and improved long term cognitive deficits after controlled-cortical impact in mice. These findings raised the possibility that Akt/mTOR might regulate necroptosis. To test this hypothesis, we induced necroptosis in the hippocampal neuronal cell line HT22 using concomitant treatment with tumor necrosis factor α (TNFα) and the pan-caspase inhibitor N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone. TNFα/zVAD treatment induced cell death within 4 h. Cell death was preceded by RIPK1–RIPK3–pAkt assembly, and phosphorylation of Thr-308 and Thr473 of AKT and its direct substrate glycogen synthase kinase-3β, as well as mTOR and its direct substrate S6 ribosomal protein (S6), suggesting activation of Akt/mTOR pathways. Pretreatment with Akt inhibitor viii and rapamycin inhibited Akt and S6 phosphorylation events, mitochondrial reactive oxygen species production, and necroptosis by over 50% without affecting RIPK1–RIPK3 complex assembly. These data were confirmed using small inhibitory ribonucleic acid-mediated knockdown of AKT1/2 and mTOR. All of the aforementioned biochemical events were inhibited by necrostatin-1, including Akt and mTOR phosphorylation, generation of oxidative stress, and RIPK1–RIPK3–pAkt complex assembly. The data suggest a novel, heretofore unexpected role for Akt and mTOR downstream of RIPK1 activation in neuronal cell death.

Risk factors for anal fistula: a case-control study

BACKGROUND

The aim of our study was to identify potential risk factors for anal fistula in order to improve prevention and treatment of anal fistula.

METHODS

A retrospective case-control study for anal fistula was conducted at our unit. Logistic regression analyses were carried out to identify associated risk factors for anal fistula.

RESULTS

The final model obtained by the stepwise forward logistic regression analysis method identified the following items as independent risk factors: body mass index of >25.0 kg/m(2), high daily salt intake, history of diabetes, hyperlipidemia, dermatosis, anorectal surgery, history of smoking and alcohol intake, sedentary lifestyle, excessive intake of spicy/greasy food, very infrequent participation in sports and prolonged sitting on the toilet for defecation.

CONCLUSIONS

Our results indicate that lifestyle factors and certain medical conditions increase an individual's risk of developing anal fistula.

Mesohepatectomy for centrally located liver tumours

BACKGROUND

Mesohepatectomy (MH) avoids unnecessary sacrifice of functional parenchyma compared with extended hepatectomy (EH). The aim of this study was to compare the results of MH with those of EH in the management of centrally located liver tumours (CLLTs).

METHODS

All patients with CLLTs treated by liver resection between 2005 and 2011 were enrolled in this retrospective study. The decision to use MH or EH was made on an individual basis. Outcomes of the procedures were compared and a classification system for MH was devised consisting of four types, with type IV representing the most complex procedure.

RESULTS

MH was performed in 292 patients and EH in 138. MH was associated with a longer duration of operation (P < 0.001), higher intraoperative transfusion rate (P < 0.001) and lower complication rates (P = 0.001) compared with EH. There were no significant differences in hepatic inflow occlusion rate (P = 0.075), blood loss (P = 0.241) and length of hospital stay (P = 0.804) between the two groups. Type IV lesions had the longest duration of operation, greatest blood loss, and highest intraoperative transfusion and morbidity rates (all P < 0.050).

CONCLUSION

MH is a feasible and safe alternative to EH in selected patients with CLLTs. The proposed classification system may be useful in guiding the surgical treatment of CLLTs.

Donor factors predictive for poor outcomes of living donor kidney transplantation

INTRODUCTION

The aim of this study was to explore donor risk factors that predict the poor outcomes after living donor kidney transplantation.

METHODS

We retrospectively analyzed our 219 living donor kidney transplantations collecting donor age and gender, graft glomeular filtration rate (GFR), human leukocyte antigen (HLA) typing, recipient age and gender, acute rejection episodes chronic rejection, and 1-year serum creatinine level. Patient and graft survivals were calculated using the Kaplan-Meier analysis. Independent donor risk factors affecting graft survival and 1-year serum creatinine level were analyzed using Cox regression and logistic regression.

RESULTS

One-, 3-, 5-year patient and graft survivals were 98.6%, 98.1%, and 97.4% and 97.7%, 95.0%, and 92.2%, respectively. Acute rejection rate was 12.8%, and chronic rejection, 4.1%. If donor age was over 50 years, there were significantly increased incidences of acute and chronic rejection (χ(2) were 5.385 and 5.039; P < .05). Univariate analysis showed donor age > 50 years, graft GFR < 35 mL/min, female to male, HLA mismatch > 3 loci to be risk factors for an abnormal 1-year serum creatinine. Logistic multivariate regression revealed donor age > 50 years, female to male, and graft GFR before transplant < 35 mL/min to be independent risk factors for an abnormal 1-year serum creatinine level (odds ratio values 5.928, 2.489, and 6.993, respectively; P < .05). Cox multivariate regression demonstrated that graft GFR before transplant < 35 mL/min was an independent risk factor for long-term graft survival (relative risk value = 6.984; P = .004).

CONCLUSION

Older donor, female to male, and insufficient graft GFR before transplantation are predictive factors for poor outcomes of living donor kidney transplantations.

Mesoporous TiO2 single crystals: facile shape-, size-, and phase-controlled growth and efficient photocatalytic performance

In this work, we have succeeded in preparing rutile and anatase TiO2 mesoporous single crystals with diverse morphologies in a controllable fashion by a simple silica-templated hydrothermal method. A simple in-template crystal growth process was put forward, which involved heterogeneous crystal nucleation and oriented growth within the template, a sheer spectator, and an excluded volume, i.e., crystal growth by faithful negative replication of the silica template. A series of mesoporous single-crystal structures, including rutile mesoporous TiO2 nanorods with tunable sizes and anatase mesoporous TiO2 nanosheets with dominant {001} facets, have been synthesized to demonstrate the versatility of the strategy. The morphology, size, and phase of the TiO2 mesoporous single crystals can be tuned easily by varying the external conditions such as the hydrohalic acid condition, seed density, and temperature rather than by the silica template, which merely serves for faithful negative replication but without interfering in the crystallization process. To demonstrate the application value of such TiO2 mesoporous single crystals, photocatalytic activity was tested. The resultant TiO2 mesoporous single crystals exhibited remarkable photocatalytic performance on hydrogen evolution and degradation of methyl orange due to their increased surface area, single-crystal nature, and the exposure of reactive crystal facets coupled with the three-dimensionally connected mesoporous architecture. It was found that {110} facets of rutile mesoporous single crystals can be considered essentially as reductive sites with a key role in the photoreduction, while {001} facets of anatase mesoporous single crystals provided oxidation sites in the oxidative process. Such shape- and size-controlled rutile and anatase mesoporous TiO2 single crystals hold great promise for building energy conversion devices, and the simple solution-based hydrothermal method is extendable to the synthesis of other mesoporous single crystals beyond TiO2.

MicroRNA expression profiling studies on bronchopulmonary dysplasia: a systematic review and meta-analysis

Over the past several years, several microRNA (miRNA) expression profiling studies have been carried out on bronchopulmonary dysplasia (BPD) in mammalian lung tissues. The most effective way to identify these important miRNAs is to systematically search for similar signatures identified in multiple independent studies. Accordingly, a meta-analysis was conducted to review published miRNA expression profiling studies that compared miRNA expression profiles between BPD lung tissues and normal lung tissues. A vote-counting strategy that considered the total number of studies and time points reporting differential expression was applied. Furthermore, cut-off criteria of statistically significant differentially expressed miRNAs as defined by the author and their predicted target genes, if available, as well as the list of up- and down-regulated miRNA features, were collected and recorded. Results of the meta-analysis revealed that four up-regulated miRNAs (miRNA-21, miRNA-34a, miRNA-431, and Let-7f) and one down-regulated miRNA (miRNA-335) were differentially expressed in BPD lung tissues compared with normal groups. In addition, eight miRNAs (miRNA-146b, miRNA-29a, miRNA-503, miRNA-411, miRNA-214, miRNA-130b, miRNA-382, and miRNA-181a-1*) were found to show differential expression not only in the process of normal lung development, but also during the progress of BPD. Finally, several meaningful target genes (such as the HPGD and NTRK genes) of common miRNAs (such as miRNA-21 and miRNA-141) were systematically predicted. These specific miRNAs may provide clues of the potential mechanisms involved in BPD. Further mechanistic and external validation studies are needed to confirm the clinical significance of these miRNAs in the development of BPD.

Contribution of serine, folate and glycine metabolism to the ATP, NADPH and purine requirements of cancer cells

Recent observations on cancer cell metabolism indicate increased serine synthesis from glucose as a marker of poor prognosis. We have predicted that a fraction of the synthesized serine is routed to a pathway for ATP production. The pathway is composed by reactions from serine synthesis, one-carbon (folate) metabolism and the glycine cleavage system (SOG pathway). Here we show that the SOG pathway is upregulated at the level of gene expression in a subset of human tumors and that its level of expression correlates with gene signatures of cell proliferation and Myc target activation. We have also estimated the SOG pathway metabolic flux in the NCI60 tumor-derived cell lines, using previously reported exchange fluxes and a personalized model of cell metabolism. We find that the estimated rates of reactions in the SOG pathway are highly correlated with the proliferation rates of these cell lines. We also observe that the SOG pathway contributes significantly to the energy requirements of biosynthesis, to the NADPH requirement for fatty acid synthesis and to the synthesis of purines. Finally, when the PC-3 prostate cancer cell line is treated with the antifolate methotrexate, we observe a decrease in the ATP levels, AMP kinase activation and a decrease in ribonucleotides and fatty acids synthesized from [1,2-¹³C₂]-D-glucose as the single tracer. Taken together our results indicate that the SOG pathway activity increases with the rate of cell proliferation and it contributes to the biosynthetic requirements of purines, ATP and NADPH of cancer cells.

RGD capsid modification enhances mucosal protective immunity of a non-human primate adenovirus vector expressing Pseudomonas aeruginosa OprF

Replication-deficient adenoviral (Ad) vectors of non-human serotypes can serve as Ad vaccine platforms to circumvent pre-existing anti-human Ad immunity. We found previously that, in addition to that feature, a non-human primate-based AdC7 vector expressing outer membrane protein F of P. aeruginosa (AdC7OprF) was more potent in inducing lung mucosal and protective immunity compared to a human Ad5-based vector. In this study we analysed if genetic modification of the AdC7 fibre to display an integrin-binding arginine-glycine-aspartic acid (RGD) sequence can further enhance lung mucosal immunogenicity of AdC7OprF. Intratracheal immunization of mice with either AdC7OprF.RGD or AdC7OprF induced robust serum levels of anti-OprF immunoglobulin (Ig)G up to 12 weeks that were higher compared to immunization with the human vectors Ad5OprF or Ad5OprF.RGD. OprF-specific cellular responses in lung T cells isolated from mice immunized with AdC7OprF.RGD and AdC7OprF were similar for T helper type 1 (Th1) [interferon (IFN)-γ in CD8(+) and interleukin (IL)-12 in CD4(+)], Th2 (IL-4, IL-5 and IL-13 in CD4(+)) and Th17 (IL-17 in CD4(+)). Interestingly, AdC7OprF.RGD induced more robust protective immunity against pulmonary infection with P. aeruginosa compared to AdC7OprF or the control Ad5 vectors. The enhanced protective immunity induced by AdC7OprF.RGD was maintained in the absence of alveolar macrophages (AM) or CD1d natural killer T cells. Together, the data suggest that addition of RGD to the fibre of an AdC7-based vaccine is useful to enhance its mucosal protective immunogenicity.

QSAR modeling of toxicity of acyclic quaternary ammonium compounds on Scenedesmus Quadricauda using 2D and 3D descriptors

Optimized calculation of typical acyclic quaternary ammonium compounds (QACs) was performed at B3LYP/6-311G** level using density functional theory (DFT) method. A two- dimensional quantitative structure-activity relationship (2D-QSAR) model was established with the obtained structure parameters as theoretical descriptors. And then three-dimensional quantitative structure-activity relationship (3D-QSAR) models were built using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) methods respectively. The 2D and 3D QSAR models exhibit optimum stability and predictive ability, revealing that steric and electronic effects influence the toxicity of acyclic QACs to Scenedesmus Quadricauda mostly.

Kidney transplantation from donors after brain or cardiac death in China--a clinical analysis of 94 cases

BACKGROUND

We analyzed outcomes of kidney transplantation (KTx) from donation after brain death (DBD) or cardiac death (DCD) in China under the current level of the health care system.

METHODS

Among 94 KTx performed from February 2007 to March 2012 in two organ transplant centers in the south of China, 50 KTx were used DBD and 44 DCD donors. We retrospectively analyzed the clinical outcomes.

RESULTS

At a mean follow-up of 25.5 months, the 1-year and 2-year graft survival rates were 96.8% and 95.2% respectively. Delayed graft function (DGF) occurred in 27.7% recipients, three of whom lost graft function. Among six observed acute rejection episodes, five were reversed. When compared to the DCD group in DBD patients were apt to recover from DGF. Serum creatinine decreased more promptly in the DBD than in DCD group. Serum creatinine in the DCD group increased after months 12, when it was significantly higher than that in the DBD group (P < .05).

CONCLUSIONS

Kidney transplantation from DBD donors showed good outcomes with few complications. Although KTx from DCD donors showed a higher DGF rate and longer duration of graft recovery, we achieved favorable short-term clinical outcome using this source.