Two 'Candidatus Liberibacter asiaticus' Strains Recently Found in California Harbor Different Prophages

'Candidatus Liberibacter asiaticus' (CLas), an α-proteobacterium, is associated with citrus Huanglongbing (HLB; yellow shoot disease). In California, two cases of CLas have been detected in Los Angeles County, one in Hacienda Heights in 2012 and the other in San Gabriel in 2015. Although all infected trees were destroyed in compliance with a state mandate, citrus industry stakeholder concerns about HLB in California are high. Little is known about the biology of CLas, particularly the California strains, hindering effective HLB management efforts. In this study, next-generation sequencing technology (Illumina MiSeq) was employed to characterize the California CLas strains. Data sets containing >4 billion (Giga) bp of sequence were generated from each CLas sample. Two prophages (P-HHCA1-2 and P-SGCA5-1) were identified by the MiSeq read mapping technique referenced to two known Florida CLas prophage sequences, SC1 and SC2. P-HHCA1-2 was an SC2-like or Type 2 prophage of 38,989 bp in size. P-SGCA5-1 was an SC1-like or Type 1 prophage of 37,487 bp in size. Phylogenetic analysis revealed that P-HHCA1-2 was part of an Asiatic lineage within the Type 2 prophage group. Similarly, P-SGCA5-1 was part of an Asiatic lineage within Type 1 prophage group. The Asiatic relatedness of both P-HHCA1-2 and P-SGCA5-1 was further presented by single nucleotide polymorphism analysis at terL (encoding prophage terminase) that has been established for CLas strain differentiation. The presence of different prophages suggests that the two California CLas strains could have been introduced from different sources. An alternative explanation is that there was a mixed CLas population containing the two types of prophages, and limited sampling in a geographic region may not accurately depict the true CLas diversity. More accurate pathway analysis may be achieved by including more strains collected from the regions.

Magnitude of and gender differences in cardiovascular risk profiles among community residents in Shenzhen, China

OBJECTIVES

Understanding the prevalence of cardiovascular disease (CVD) risk factors has an impact on the public policy for initiating CVD prevention. This study aimed to examine the prevalence of current smoking, overweight/obesity, hypertension, diabetes mellitus (DM), and dyslipidemia among Shenzhen residents and to investigate gender differences in CVD risk profiles to identify the subgroups at higher risk.

STUDY DESIGN

A large cross-sectional study was conducted between April and May 2015.

METHODS

Using multistage cluster random sampling methods, a total of 1784 residents finished the face-toface interview survey. Physical examinations and blood tests were performed by qualified professionals.

RESULTS

The prevalence of current smoking, overweight/obesity, hypertension, DM, and dyslipidemia were 21.8%, 40.6%, 17.6%, 4.8%, and 35.7%, respectively. Clustering of two or more or three or more of CVD risk factors was noted in 35.7% and 14.1% of participants. The prevalence of current smoking (45.0% vs 1.1%, P < 0.001), overweight/obesity (48.5% vs 33.4%, P < 0.001), hypertension (19.7% vs 15.7%, P < 0.05), and dyslipidemia (46.5% vs 20.5%, P < 0.001) was found higher among male than among female participants.

CONCLUSIONS

This study adds to the evidence suggesting high prevalence rates of CVD risk factors and composite measures among Shenzhen residents. The higher level of CVD risk factors in male than in female residents is suggested. Effective population-based intervention programs such as smoking cessation, early detection, management, and treatment of hypertension, DM, and dyslipidemia should be initiated and enhanced especially among the males.

Protein arginine methyltransferase 5 functions as an epigenetic activator of the androgen receptor to promote prostate cancer cell growth

Protein arginine methyltransferase 5 (PRMT5) is an emerging epigenetic enzyme that mainly represses transcription of target genes via symmetric dimethylation of arginine residues on histones H4R3, H3R8 and H2AR3. Accumulating evidence suggests that PRMT5 may function as an oncogene to drive cancer cell growth by epigenetic inactivation of several tumor suppressors. Here, we provide evidence that PRMT5 promotes prostate cancer cell growth by epigenetically activating transcription of the androgen receptor (AR) in prostate cancer cells. Knockdown of PRMT5 or inhibition of PRMT5 by a specific inhibitor reduces the expression of AR and suppresses the growth of multiple AR-positive, but not AR-negative, prostate cancer cells. Significantly, knockdown of PRMT5 in AR-positive LNCaP cells completely suppresses the growth of xenograft tumors in mice. Molecular analysis reveals that PRMT5 binds to the proximal promoter region of the AR gene and contributes mainly to the enriched symmetric dimethylation of H4R3 in the same region. Mechanistically, PRMT5 is recruited to the AR promoter by its interaction with Sp1, the major transcription factor responsible for AR transcription, and forms a complex with Brg1, an ATP-dependent chromatin remodeler, on the proximal promoter region of the AR gene. Furthermore, PRMT5 expression in prostate cancer tissues is significantly higher than that in benign prostatic hyperplasia tissues, and PRMT5 expression correlates positively with AR expression at both the protein and mRNA levels. Taken together, our results identify PRMT5 as a novel epigenetic activator of AR in prostate cancer. Given that inhibiting AR transcriptional activity or androgen synthesis remains the major mechanism of action for most existing anti-androgen agents, our findings also raise an interesting possibility that targeting PRMT5 may represent a novel approach for prostate cancer treatment by eliminating AR expression.

An integrated analysis identifies STAT4 as a key regulator of ovarian cancer metastasis

Epithelial ovarian cancer (EOC) is one of the most common gynecological cancers, with diagnosis often at a late stage. Metastasis is a major cause of death in patients with EOC, but the underlying molecular mechanisms remain obscure. Here, we utilized an integrated approach to find potential key transcription factors involved in ovarian cancer metastasis and identified STAT4 as a critical player in ovarian cancer metastasis. We found that activated STAT4 was overexpressed in epithelial cells of ovarian cancer and STAT4 overexpression was associated with poor outcome of ovarian cancer patients, which promoted metastasis of ovarian cancer in both in vivo and in vitro. Although STAT4 mediated EOC metastasis via inducing epithelial-to-mesenchymal transition (EMT) of ovarian cancer cells in vivo, STAT4 failed to induce EMT directly in vitro, suggesting that STAT4 might mediate EMT process via cancer-stroma interactions. Further functional analysis revealed that STAT4 overexpression induced normal omental fibroblasts and adipose- and bone marrow-derived mesenchymal stem cells to obtain cancer-associated fibroblasts (CAF)-like features via induction of tumor-derived Wnt7a. Reciprocally, increased production of CAF-induced CXCL12, IL6 and VEGFA within tumor microenvironment could enable peritoneal metastasis of ovarian cancer via induction of EMT program. In summary, our study established a model that STAT4 promotes ovarian cancer metastasis via tumor-derived Wnt7a-induced activation of CAFs.

Identification of a PRX variant in a Chinese family with congenital cataract by exome sequencing

BACKGROUND

Congenital cataract is a common cause of childhood vision impairment or blindness with genetic and clinical heterogeneity. The aim of this study was to identify the disease-associated gene in a Chinese family with congenital cataract.

METHODS

A four-generation Chinese family with three enrolled patients suffering from congenital cataract was studied. Detailed family history and clinical data of all the members were collected and recorded. Exome sequencing was applied in the proband to screen potential genetic variants, and then Sanger sequencing was used to verify the variant within the family.

RESULTS

A heterozygous variant, c.3673G > A (p.V1225M), in the periaxin gene (PRX) was identified in three patients and two asymptomatic individuals of the family. The variant was absent in the other three unaffected family members and in 3290 ethnically matched in-house controls from BGI-Shenzhen.

CONCLUSIONS

By utilizing both exome sequencing and Sanger sequencing, we identified a missense variant in the PRX gene that is possibly associated with disease in this family. Our finding may broaden the spectrum of genes associated with congenital cataract, and may provide insights into lens development, pathogenic mechanism, future clinical genetic diagnosis and therapy of congenital cataract.

[The efficacy of large spot indirect ophthalmoscopy laser alone or combined with systemic chemotherapy in retinoblastoma therapy]

Objective: To evaluate the efficacy of large spot indirect ophthalmoscopy laser alone or combined with systemic chemotherapy in the treatment of early and middle stage retinoblastoma. Methods: Retrospective series case study. Clinical data of 21 patients (22 eyes) who were diagnosed as retinoblastoma (RB) in Peking University People's Hospital from March 2009 to August 2014 were collected. Medical and family history, ocular ultrasound, orbital and cranial MRI or CT examination of RB Children were detailed recorded. Ocular examination and laser treatment were performed under general anesthesia, once every 3-4 weeks until the tumor was under control. The observation period was at least 3 months after the last treatment. The ocular examination included intraocular pressure measurement, anterior segment and fundus examination and the fundus photography with Retcam. Laser therapeutic instrument was large spot indirect ophthalmoscopy laser of 810nm wavelength. Results: Of the 21 children, 16 were male and 5 were female. The range of age was 3 to 82 months averaged 17.3 months. Among 22 eyes, four with small tumor, eight with medium tumor, and ten with large tumor. Two eyes underwent laser treatment only and 20 eyes underwent laser treatment combined with systemic chemotherapy. During the average observation period of 33.9 months, 15 tumors were treated successfully, but 7 failed. The total success rate was 68.2%. The number and success rate of small, medium and large tumor eyes were 4 (100%), 5 (62.5%) and 5 (50%), respectively. There was one case of tumor brain metastases, and the classification of contralateral eye of the child was E phase.

COMPLICATIONS

Iris burns happened in one eye, obvious vitreous proliferation in one eye and mild vitreous hemorrhage occurred in two eyes, which did not affect the treatment of laser. However, obvious tumor hemorrhage happened in two eyes and affected laser therapy. There was no complicated cataract, iatrogenic retinal hole and tumor intravitreal implant caused by laser blasting effect. Conclusions: Indirect ophthalmoscope laser in 810-nm diode laser with large-spot alone or combined with systemic chemotherapy may be effective treatment for retinoblastoma in earlier than stage C of international classification. It is suitable for large and multiple retinoblastoma.(Chin J Ophthalmol, 2016, 52: 745-748).

[Economic evaluation on different two-dose-vaccination-strategies related to Measles, Mumps and Rubella Combined Attenuated Live Vaccine]

OBJECTIVE

To evaluate the economic effect of Measles, Mumps and Rubella Combined Attenuated Live Vaccine (MMR) under different two-dose vaccination programs.

METHODS

A hypothetical birth cohort of 750 000 infants over their lifetime, was followed up from birth through death in Zhejiang province. The current MMR vaccination strategie would include three different ones: 1) Childlern were vaccinated with Measles-Rubella Combined Attenuated Live Vaccine and MMR, respectively at the age of 8 months and 18 months. 2) Children receive MMR at 8 months and 18 months, 3) Strategy 1 plus an additional vaccination of MMR at 4 years of age. Incremental cost-effectiveness ratio (ICER), incremental cost-benefit ratio (ICBR) and incremental net benefit (INB) were applied to calculate the health economic difference for Strategy 2 and Strategy 3 as compared to Strategy 1. Univariate sensitivity analysis was used to assess the robustness of results with main parameters, including the rate of immunization coverage, effectiveness of the vaccines, incidence and burdens of the related diseases, cost of vaccines and the vaccination program itself.

RESULTS

ICER, ICBR and INB for Strategy 2 and Strategy 3 appeared as 2 012.51∶1 RMB Yuan per case and 4 238.72∶1 RMB Yuan per case, 1∶3.14 and 1∶1.58, 21 277 800 RMB Yuan and 9 276 500 RMB Yuan, respectively. Only slight changes (<20%) were found under the univariate sensitivity analysis, with varied values on main parameters.

CONCLUSION

Based on the current national immunization program, infants vaccinated with MMR at 8 months of age, generated more health economic effects than the Strategy 3.

Quantum Levy Flights and Multifractality of Dipolar Excitations in a Random System

We consider dipolar excitations propagating via dipole-induced exchange among immobile molecules randomly spaced in a lattice. The character of the propagation is determined by long-range hops (Levy flights). We analyze the eigenenergy spectra and the multifractal structure of the wave functions. In 1D and 2D, all states are localized, although in 2D the localization length can be extremely large leading to an effective localization-delocalization crossover in realistic systems. In 3D, all eigenstates are extended but not always ergodic, and we identify the energy intervals of ergodic and nonergodic states. The reduction of the lattice filling induces an ergodic to nonergodic transition, and the excitations are mostly nonergodic at low filling.

Identification of genetic variants associated with susceptibility to West Nile virus neuroinvasive disease

West Nile virus (WNV) infection results in a diverse spectrum of outcomes, and host genetics are likely to influence susceptibility to neuroinvasive disease (West Nile neuroinvasive disease (WNND)). We performed whole-exome sequencing of 44 individuals with WNND and identified alleles associated with severe disease by variant filtration in cases, kernel association testing in cases and controls and single-nucleotide polymorphism (SNP) imputation into a larger cohort of WNND cases and seropositive controls followed by genome-wide association analysis. Variant filtration prioritized genes based on the enrichment of otherwise rare variants, but did not unambiguously implicate variants shared by a majority of cases. Kernel association demonstrated enrichment for risk and protective alleles in the human leukocyte antigen (HLA)-A and HLA-DQB1 loci that have well understood roles in antiviral immunity. Two loci, HERC5 and an intergenic region between CD83 and JARID2, were implicated by multiple imputed SNPs and exceeded genome-wide significance in a discovery cohort (n=862). SNPs at two additional loci, TFCP2L1 and CACNA1H, achieved genome-wide significance after association testing of directly genotyped and imputed SNPs in a discovery cohort (n=862) and a separate replication cohort (n=1387). The context of these loci suggests that immunoregulatory, ion channel and endothelial barrier functions may be important elements of the host response to WNV.

Vitamin D improves diabetic nephropathy in rats by inhibiting renin and relieving oxidative stress

BACKGROUND

It is well established that the activation of the renin-angiotensin system (RAS) and the oxidative stress caused by hyperglycemia are major mediators of the development and progression of diabetic nephropathy (DN). Vitamin D may be important in maintaining podocyte health, preventing epithelial-to-mesenchymal transformation, and suppressing renin gene expression and inflammation, but its mechanism requires clarification. This study evaluated the specific mechanism of vitamin D to DN improvement.

METHODS

We induced a rat model of diabetes with an intraperitoneal injection of streptozotocin (60 mg/kg). The streptozotocin-induced diabetic rats were fed normal chow for about 2 months to induce the DN model. The DN rats were then treated with irbesartan and/or calcitriol, administered intragastrically about 1 month.

RESULTS

The rats displayed the early characteristics of DN, including increased microalbuminuria, obvious hypertrophic kidney, and a markedly increased kidney weight/bodyweight ratio. Vitamin D inhibited the compensatory increase in renin expression. Malondialdehyde, which reflects oxidative stress levels, was elevated in the DN group rats and their antioxidant capacity was significantly reduced. The irbesartan and calcitriol interventions markedly improved the renal pathology and pathophysiological changes. Irbesartan combined with vitamin D (calcitriol) more effectively ameliorated DN than irbesartan alone.

CONCLUSIONS

Vitamin D combined with angiotensin II type 1 receptor blockers exerts a synergistic effect on the treatment of DN, not only by inhibiting renin but also by reducing oxidative stress and increasing the renal antioxidant capacity.

Draft Genome Sequence of Xylella fastidiosa subsp. fastidiosa Strain Stag's Leap

ITALIC! Xylella fastidiosasubsp. ITALIC! fastidiosacauses Pierce's disease of grapevine. Presented here is the draft genome sequence of the Stag's Leap strain, previously used in pathogenicity/virulence assays to evaluate grapevine germplasm bearing Pierce's disease resistance and a phenotypic assessment of knockout mutants to determine gene function.

Photoluminescence characterisations of a dynamic aging process of organic-inorganic CH3NH3PbBr3 perovskite

After unprecedented development of organic-inorganic lead halide perovskite solar cells over the past few years, one of the biggest barriers towards their commercialization is the stability of the perovskite material. It is thus important to understand the interaction between the perovskite material and oxygen and/or humidity and the associated degradation process in order to improve device and encapsulation design for better durability. Here we characterize the dynamic aging process in vapour-assisted deposited (VASP) CH3NH3PbBr3 perovskite thin films using advanced optical techniques, such as time-resolved photoluminescence and fluorescence lifetime imaging microscopy (FLIM). Our investigation reveals that the perovskite grains grow spontaneously and the larger grains are formed at room temperature in the presence of moisture and oxygen. This crystallization process leads to a higher density of defects and a shorter carrier lifetime, specifically in the larger grains. Excitation-intensity-dependent steady-state photoluminescence shows both N2 stored and aged perovskite exhibit a super-linear increase of photoluminescence intensity with increasing excitation intensity; and the larger slope in aged sample suggests a larger density of defects is generated, consistent with time-resolved PL measurements.

Draft Genome Sequence of "Candidatus Liberibacter asiaticus" from a Citrus Tree in San Gabriel, California

The draft genome sequence of "Candidatus Liberibacter asiaticus" strain SGCA5 from an orange citrus tree in San Gabriel, California, is reported here. SGCA5 has a genome size of 1,201,445 bp, a G+C content of 36.4%, 1,152 predicted open reading frames (ORFs), and 42 RNA genes.