Development of a High-Efficient Mutation Resource with Phenotypic Variation in Hexaploid Winter Wheat and Identification of Novel Alleles in the TaAGP.L-B1 Gene

Mutated genetic resources play an important role in gene/allele characterization. Currently, there are few hexaploid winter wheat mutated resources available. Here, we developed a hexaploid winter wheat resource by inducing mutations via EMS treatment by the single seed descent method. A broad mutation spectrum with high mutation frequency (∼19%) on phenotypic variations was identified. These mutations included spike, leaf and seed morphology, plant architecture, and heading date variations. To evaluate the efficiency of the resource for reverse genetic analysis, allelic variations in the TaAGP.L-B1 gene, encoding the AGPase large subunit, were screened by the TILLING approach. Four missense mutations were identified and one allele in line E3-1-3, resulted in an amino acid change predicated to have severe effects on gene function. The other three mutations were predicted to have no effect. Results of gene expression patterns and grain starch content demonstrated that the novel allele in E3-1-3 altered the function of TaAGP.L-B1. Our results indicated that this mutated genetic wheat resource contained broad spectrum phenotypic and genotypic variations, that may be useful for wheat improvement, gene discovery, and functional genomics.

Measuring impairments of functioning and health in patients with axial spondyloarthritis by using the ASAS Health Index and the Environmental Item Set: translation and cross-cultural adaptation into 15 languages

Introduction

The Assessments of SpondyloArthritis international society Health Index (ASAS HI) measures functioning and health in patients with spondyloarthritis (SpA) across 17 aspects of health and 9 environmental factors (EF). The objective was to translate and adapt the original English version of the ASAS HI, including the EF Item Set, cross-culturally into 15 languages.

Methods

Translation and cross-cultural adaptation has been carried out following the forward–backward procedure. In the cognitive debriefing, 10 patients/country across a broad spectrum of sociodemographic background, were included.

Results

The ASAS HI and the EF Item Set were translated into Arabic, Chinese, Croatian, Dutch, French, German, Greek, Hungarian, Italian, Korean, Portuguese, Russian, Spanish, Thai and Turkish. Some difficulties were experienced with translation of the contextual factors indicating that these concepts may be more culturally-dependent. A total of 215 patients with axial SpA across 23 countries (62.3% men, mean (SD) age 42.4 (13.9) years) participated in the field test. Cognitive debriefing showed that items of the ASAS HI and EF Item Set are clear, relevant and comprehensive. All versions were accepted with minor modifications with respect to item wording and response option. The wording of three items had to be adapted to improve clarity. As a result of cognitive debriefing, a new response option ‘not applicable’ was added to two items of the ASAS HI to improve appropriateness.

Discussion

This study showed that the items of the ASAS HI including the EFs were readily adaptable throughout all countries, indicating that the concepts covered were comprehensive, clear and meaningful in different cultures.

TRPM7 channel inhibition mediates midazolam-induced proliferation loss in human malignant glioma

The melastatin-like transient receptor potential 7 (TRPM7) has been implicated in proliferation or apoptosis of some cancers, indicating the potential of TRPM7 as an anti-anaplastic target. Here, we identified the characteristic TRPM7 channel currents in human malignant glioma MGR2 cells, which could be blocked by a pharmacologic inhibitor Gd³⁺. We mined the clinical sample data from Oncomine Database and found that human malignant glioma tissues expressed higher TRPM7 mRNA than normal brain ones. Importantly, we identified a widely used clinical anesthetic midazolam as a TRPM7 inhibitor. Midazolam treatment for seconds suppressed the TRPM7 currents and calcium influx, and treatment for 48 h inhibited the TRPM7 expression. The inhibitory effect on TRPM7 accounts for the proliferation loss and G₀/G₁ phase cell cycle arrest induced by midazolam. Our data demonstrates that midazolam represses proliferation of human malignant glioma cells through inhibiting TRPM7 currents, which may be further potentiated by suppressing the expression of TRPM7. Our result indicates midazolam as a pharmacologic lead compound with brain-blood barrier permeability for targeting TRPM7 in the glioma.

[Correlation between RNA Expression Level and Early PMI in Human Brain Tissue]

OBJECTIVES

To explore the correlation between the expression levels of several RNA markers in human brain tissue and early postmortem interval （PMI）.

METHODS

Twelve individuals with known PMI （range from 4.3 to 22.5 h） were selected and total RNA was extracted from brain tissue. Eight commonly used RNA markers were chosen including β-actin, GAPDH, RPS29, 18S rRNA, 5S rRNA, U6 snRNA, miRNA-9 and miRNA-125b, and the expression levels were detected in brain tissue by real-time fluorescent quantitative PCR. The internal reference markers with stable expression in early PMI were screened using geNorm software and the relationship between its expression level and some relevant factors such as age, gender and cause of death were analyzed. RNA markers normalized by internal reference were inserted into the mathematic model established by previous research for PMI estimation using R software. Model quality was judged by the error rate calculated with estimated PMI.

RESULTS

5S rRNA, miRNA-9 and miRNA-125b showed quite stable expression and their expression levels had no relation with age, gender and cause of death. The error rate of estimated PMI using β-actin was 24.6%, while GAPDH was 41.0%.

CONCLUSIONS

5S rRNA, miRNA-9 and miRNA-125b are suitable as internal reference markers of human brain tissue owing to their stable expression in early PMI. The expression level of β-actin correlates well with PMI, which can be used as an additional index for early PMI estimation.

Factors Affecting the Radiosensitivity of Hexaploid Wheat to γ-Irradiation: Radiosensitivity of Hexaploid Wheat (Triticum aestivum L.) [Corrected]

Understanding the radiosensitivity of plants, an important factor in crop mutation breeding programs, requires a thorough investigation of the factors that contribute to this trait. In this study, we used the highly radiosensitive wheat (Triticum aestivum L.) variety HY1 and J411, a γ-irradiation-insensitive control, which were screened from a natural population, to examine the factors affecting radiosensitivity, including free radical content and total antioxidant capacity, as well as the expression of TaKu70 and TaKu80 (DNA repair-related genes) as measured by real-time PCR. We also investigated the alternative splicing of this gene in the wild-type wheat ecotype by sequence analysis. Free radical contents and total antioxidant capacity significantly increased upon exposure of HY1 wheat to γ-irradiation in a dose-dependent manner. By contrast, in J411, the free radical contents exhibited a similar trend, but the total antioxidant capacity exhibited a downward trend upon increasing γ-irradiation. Additionally, we detected dose-dependent increases in TaKu70 and TaKu80 expression levels in γ-irradiated HY1, while in J411, TaKu70 expression levels increased, followed by a decline. We also detected alternative splicing of TaKu70 mRNA, namely, intron retention, in HY1 but not in J411. Our findings indicate that γ-irradiation induces oxidative stress and DNA damage in hexaploid wheat, resulting in growth retardation of seedlings, and they suggest that TaKu70 may play a causal role in radiosensitivity in HY1. Further studies are required to exploit these factors to improve radiosensitivity in other wheat varieties.

Efficacy and safety of adalimumab in Chinese patients with moderate-to-severe plaque psoriasis: results from a phase 3, randomized, placebo-controlled, double-blind study

Background

This phase 3 trial is the first to evaluate the efficacy and safety of treatment with the systemic TNF‐α inhibitor, adalimumab, for Chinese patients with moderate‐to‐severe plaque psoriasis.

Methods

In the 12‐week, double‐blind, placebo‐controlled Period A, patients were randomized 4 : 1 to receive adalimumab 40 mg every‐other‐week (following a single 80 mg dose), or placebo every‐other‐week. In the subsequent 12‐week, open‐label, Period B, all patients received adalimumab 40 mg every‐other‐week starting at week 13, following a single, blinded dose at week 12 of adalimumab 80 mg or matching placebo (for patients receiving placebo or adalimumab in Period A respectively). In Period A, efficacy was analysed for all randomized patients and safety for all patients receiving ≥1 dose of the study drug.

Results

For the 425 patients in this study (87 placebo; 338 adalimumab), a higher percentage randomized to adalimumab achieved the primary endpoint of ≥75% improvement from baseline in PASI score (PASI 75) at week 12: placebo 11.5% (10/87); adalimumab 77.8% (263/338; P < 0.001). Physician's Global Assessment of clear to minimal was achieved at week 12 by 14.9% placebo (13/87) and 80.5% adalimumab (272/338; P < 0.001). For patients who received adalimumab at any time during the study (All‐adalimumab Population), treatment‐emergent adverse events (AEs) were reported by 63.4%; the most common was upper respiratory infection (16.1%). Serious AEs were reported by 3.5% of the All‐adalimumab Population, and serious infectious AEs by 1.2%, which include lung infection, pneumonia and tuberculosis [2 (0.5%) patients each]. There was one death (chronic heart failure).

Conclusion

In these Chinese patients with moderate‐to‐severe psoriasis, a significantly greater percentage treated with adalimumab compared with placebo achieved efficacy endpoints at week 12 and efficacy was sustained to week 24. Safety results were consistent with the known adalimumab safety profile; no new safety signals were identified in the 24 weeks of treatment.

Effects of LeY glycan expression on embryo implantation

OBJECTIVE

To investigate the correlation between LeY glycan expression and embryo implantation.

MATERIALS AND METHODS

Uterine epithelial cells before implantation were transfected with FUT1siRNA to inhibit FUT1 (the gene encoding the key enzyme of LeY synthesis) expression and treated with 10 ng/ml leukemia inhibitory factor (LIF). Murine embryo implantation model in vitro was prepared by late blastocysts with identical morphology and treated uterine epithelial cells co-culture. Using RT-PCR, dot blot and observation of embryo attachment to analyze FUT1 gene expression and LeY synthesis of uterine epithelial cells and studied further the correlation of LeY expression level and embryo implantation.

RESULTS

FUT1 gene expression and LeY synthesis declined after cells were transfected with FUT1siRNA, and LIF promoted FUT1 expression and LeY synthesis. After expression of FUT1 gene was inhibited, attachment rate of embryos lowered, but LIF up-regulated FUT1 expression and increased the attachment rate of embryos.

CONCLUSIONS

These results indicated regulating FUT1 expression affected LeY synthesis, and then LeY regulated the recognition and attachment of uterus-embryo and participates in embryo implantation further.

Mate choice and host discrimination behavior of the parasitoid Trichogramma chilonis

Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae) is an important natural enemy of many species of lepidopterous pests and a widely used biological control agent. Detailed knowledge about its mate choice and host discrimination behavior is lacking. In this study, we studied the mate choice and host discrimination behavior of T. chilonis in experimental arenas through video tracking. Males' mate recognition capacity was realized by perceiving the sex pheromone of females. When offered two females of different species, male could distinguish the conspecific female from Trichogrammatoidea bactrae Nagaraja (Hymenoptera: Trichogrammatidae), a species that has overlapping hosts with T. chilonis. When placed with two females of different mating status, male preferred mating with the virgin female to the mated female. T. chilonis females could distinguish unparasitized host eggs from parasitized ones (parasitized by conspecific females or heterospecific females). They preferred to stay on and lay eggs in unparasitized host eggs. When T. chilonis females were only provided with parasitized host eggs (parasitized by T. chilonis and T. bactrae females), conspecific superparasitism occurred more often than heterospecific superparasitism. Furthermore, the host egg discrimination ability of T. chilonis females was mainly achieved through antennal perception.

Naturally Existing Oncolytic Virus M1 Is Nonpathogenic for the Nonhuman Primates After Multiple Rounds of Repeated Intravenous Injections

Cancers figure among the leading causes of morbidity and mortality worldwide. The number of new cases is expected to rise by about 70% over the next 2 decades. Development of novel therapeutic agents is urgently needed for clinical cancer therapy. Alphavirus M1 is a Getah-like virus isolated from China with a genome of positive single-strand RNA. We have previously identified that alphavirus M1 is a naturally existing oncolytic virus with significant anticancer activity against different kinds of cancer (e.g., liver cancer, bladder cancer, and colon cancer). To support the incoming clinical trial of intravenous administration of alphavirus M1 to cancer patients, we assessed the safety of M1 in adult nonhuman primates. We previously presented the genome sequencing data of the cynomolgus macaques (Macaca fascicularis), which was demonstrated as an ideal animal species for virus infection study. Therefore, we chose cynomolgus macaques of either sex for the present safety study of oncolytic virus M1. In the first round of administration, five experimental macaques were intravenously injected with six times of oncolytic virus M1 (1 × 10(9) pfu/dose) in 1 week, compared with five vehicle-injected control animals. The last two rounds of injections were further completed in the following months in the same way as the first round. Body weight, temperature, complete blood count, clinical biochemistries, cytokine profiles, lymphocytes subsets, neutralizing antibody, and clinical symptoms were closely monitored at different time points. Magnetic resonance imaging was also performed to assess the possibility of encephalitis or arthritis. As a result, no clinical, biochemical, immunological, or medical imaging or other pathological evidence of toxicity was found during the whole process of the study. Our results in cynomolgus macaques suggested the safety of intravenous administration of oncolytic virus M1 in cancer patients in the future.

TGF-β1-induced transcription factor networks in Langerhans cell development and maintenance

Langerhans cells (LC) represent a specialized subset of evolutionarily conserved dendritic cells (DC) that populate stratified epithelial tissues, which are essential for the induction of skin and mucosal immunity and tolerance, including allergy. Transforming growth factor-β1 (TGF-β1) has been confirmed to be a predominant factor involved in LC development. Despite great advances in the understanding of LC ontogeny and diverse replenishment patterns, the underlying molecular mechanisms remain elusive. This review focuses on the recent discoveries in TGF-β1-mediated LC development and maintenance, with special attention to the involved transcription factors and related regulators.

Mannan Derivatives Instruct Dendritic Cells to Induce Th1/Th2 Cells Polarization via Differential Mitogen-Activated Protein Kinase Activation

Mannan derived from fungal cell walls have potential uses as immunomodulating agents and vaccine adjuvants. Immunization with antigen conjugated to oxidized mannan (OM) or reduced mannan (RM) have induced differential immune responses in mice. Yet, the adjuvant effect and differences in molecular profiles of OM and RM on APCs is unresolved. Here, we investigated the response of mouse bone marrow-derived DCs to OM and RM. OM and RM stimulated DCs to produce differential Th1/Th2-inducing cytokines in vitro. OM and RM-activated DCs stimulated allogeneic T-cell Th1 and Th2 polarization reaction. OM instruct DCs to stimulate Th1 responses via IL-12p70 production, which depends on the phosphorylation of p38, RM barely induce IL-12p70, but IL-10 and IL-4, and magnitude of ERK phosphorylation, which results in a Th2 bias. These findings indicate that OM and RM were potent adjuvant capable of directly initiating DC activation Th1 and Th2 polarization respectively.

Dynamics and regulation of glycolysis-tricarboxylic acid metabolism in the midgut of Spodoptera litura during metamorphosis

Significant changes usually take place in the internal metabolism of insects during metamorphosis. The glycolysis-tricarboxylic acid (glycolysis-TCA) pathway is important for energy metabolism. To elucidate its dynamics, the mRNA levels of genes involved in this pathway were examined in the midgut of Spodoptera litura during metamorphosis, and the pyruvate content was quantified. The expression patterns of these genes in response to starvation were examined, and the interaction between protein phosphatase 1 (PP1) and phosphofructokinase (PFK) was studied. The results revealed that the expression or activities of most glycolytic enzymes was down-regulated in prepupae and then recovered in some degree in pupae, and all TCA-related genes were remarkably suppressed in both the prepupae and pupae. Pyruvate was enriched in the pupal midgut. Taken together, these results suggest that insects decrease both glycolysis and TCA in prepupae to save energy and then up-regulate glycolysis but down-regulate TCA in pupae to increase the supply of intermediates for construction of new organs. The expression of all these genes were down-regulated by starvation, indicating that non-feeding during metamorphosis may be a regulator of glycolysis-TCA pathway in the midgut. Importantly, interaction between PP1 and PFK was identified and is suggested to be involved in the regulation of glycolysis.

Risk factors associated with portomesenteric venous thrombosis in patients undergoing restorative proctocolectomy for medically refractory ulcerative colitis

AIM

Data on risk factors for portomesenteric venous thrombosis (PMVT) following abdominal surgery for ulcerative colitis (UC) are limited. The aim of this study was to investigate factors associated with PMVT after surgical treatment for UC.

METHOD

Patients who underwent restorative proctocolectomy (RPC) and ileal pouch-anal anastomosis (IPAA) including diverting ileostomy closure for medically refractory UC were identified from a prospectively maintained database. Patient-related, disease-related and treatment-related variables were collected. Univariable and multivariable analyses were performed to assess factors associated with PMVT.

RESULTS

Of the 521 patients completing surgical treatment for UC between 2006 and 2012, symptomatic PMVT occurred in 36 (7%), which resulted in a significantly increased hospital stay (P < 0.001). Patients developing PMVT were younger (P = 0.014), had a lower preoperative albumin level (P = 0.037) and were more likely to have been taking steroids within 1 month before surgery (P = 0.006). The combined incidence of PMVT was comparable between patients having a three-stage and two-stage management (6% vs. 8%, P = 0.43), but the relative incidence of PMVT after RPC + IPAA was 8%, significantly higher than the 4% after total abdominal colectomy (TAC) (P = 0.005) and the 2% after subsequent completion proctectomy (CP) + IPAA (P = 0.038). Multivariate analysis confirmed that RPC + IPAA was associated with a significantly greater risk of PMVT than CP + IPAA (OR = 4.9, P = 0.003) or TAC (OR = 3.5, P = 0.011). Preoperative steroid use was an independent factor for PMVT (OR = 5.8, P = 0.006).

CONCLUSION

Steroid use 1 month before surgery is associated with an increased risk of PMVT. A staged restorative proctocolectomy does not increase the overall incidence of PMVT.

Colon cancer with unresectable synchronous metastases: the AAAP scoring system for predicting the outcome after primary tumour resection

AIM

The aim of this study was to develop a prognostic scoring system to predict the outcome of patients with unresectable metastatic colon cancer who received primary colon tumour resection.

METHOD

Patients with confirmed metastatic colon cancer treated at the Peking University Cancer Hospital between 2003 and 2012 were reviewed retrospectively. The correlation of clinicopathological factors with overall survival was analysed using the Kaplan-Meier method and the log-rank test. Independent prognostic factors were identified using a Cox proportional hazards regression model and were then combined to form a prognostic scoring system.

RESULTS

A total of 110 eligible patients were included in the study. The median survival time was 10.4 months and the 2-year overall survival (OS) rate was 21.8%. Age over 70 years, an alkaline phosphatase (ALP) level over 160 IU/l, ascites, a platelet/lymphocyte ratio (PLR) above 162 and no postoperative therapy were independently associated with a shorter OS in multivariate analysis. Age, ALP, ascites and PLR were subsequently combined to form the so-called AAAP scoring system. Patients were classified into high, medium and low risk groups according to the score obtained. There were significant differences in OS between each group (P < 0.001).

CONCLUSION

Age, ALP, ascites, PLR and postoperative therapy were independent prognostic factors for survival of patients with metastatic colonic cancer who underwent primary tumour resection. The AAAP scoring system may be a useful tool for surgical decision making.

Role of bicyclol in preventing drug-induced liver injury in tuberculosis patients with liver disease

SETTING

Four hospitals in China.

OBJECTIVE

To evaluate the clinical efficacy and safety of using bicyclol in conjunction with glucurolactone in preventing drug-induced liver injury (DILI) in tuberculosis (TB) patients suffering from underlying liver disease.

DESIGN

A total of 240 initially treated TB patients who were healthy hepatitis B carriers or had pure steatosis were randomised into two equal groups; both received an oral glucurolactone tablet 600 mg/day (200 mg three times daily) as basic liver protection. The test group also received 75 mg/day (25 mg three times daily) bicyclol tablets orally, while the control group received no other liver protection. The incidence of liver injury in the two groups, the adjustment or termination of anti-tuberculosis chemotherapy and any adverse reactions were assessed.

RESULTS

The incidence rate and level of severity of liver injury and the termination rate of anti-tuberculosis treatment in the test group were lower than that of the control group (P < 0.05). The overall time of occurrence of liver injury was significantly different between the two groups (P < 0.05).

CONCLUSION

Adding bicyclol to basic liver protectants may effectively and safely prevent the occurrence of anti-tuberculosis DILI in patients with underlying liver disease, and help simplify anti-tuberculosis treatment.

Severe obesity prior to diagnosis limits survival in colorectal cancer patients evaluated at a large cancer centre

Background:

In contrast to the consistent evidence for obesity and colorectal cancer (CRC) risk, the impact of obesity in CRC patients is less clear. In a well-characterised cohort of CRC patients, we prospectively evaluated class I and class II obesity with survival outcomes.

Methods:

The CRC patients (N=634) were followed from the date of diagnosis until disease progression/first recurrence (progression-free survival (PFS)) or death (overall survival (OS)). Body mass index (BMI) was calculated from reported usual weight prior to diagnosis. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated in models adjusted for clinicopathologic, treatment, and lifestyle factors.

Results:

Over a median follow-up of 4 years, 208 (33%) patients died and 235 (37%) recurred or progressed. Class II obesity, as compared with either overweight or normal weight, was associated with an increased risk of death (HR and 95% CI: 1.55 (0.97–2.48) and 1.65 (1.02–2.68), respectively), but no clear association was observed with PFS. In analyses restricted to patients who presented as stages I–III, who reported stable weight, or who were aged <50 years, obesity was associated with a significant two- to five-fold increased risk of death.

Conclusions:

In CRC patients evaluated at a large cancer centre, severely obese patients experienced worse survival outcomes independent of many other factors.

Multiple region whole-exome sequencing reveals dramatically evolving intratumor genomic heterogeneity in esophageal squamous cell carcinoma

Cancer is a disease of genome instability and genomic alterations; now, genomic heterogeneity is rapidly emerging as a defining feature of cancer, both within and between tumors. Motivation for our pilot study of tumor heterogeneity in esophageal squamous cell carcinoma (ESCC) is that it is not well studied, but the highest incidences of esophageal cancers are found in China and ESCC is the most common type. We profiled the mutations and changes in copy number that were identified by whole-exome sequencing and array-based comparative genomic hybridization in multiple regions within an ESCC from two patients. The average mutational heterogeneity rate was 90% in all regions of the individual tumors in each patient; most somatic point mutations were nonsynonymous substitutions, small Indels occurred in untranslated regions of genes, and copy number alterations varied among multiple regions of a tumor. Independent Sanger sequencing technology confirmed selected gene mutations with more than 88% concordance. Phylogenetic analysis of the somatic mutation frequency demonstrated that multiple, genomically heterogeneous divergent clones evolve and co-exist within a primary ESCC and metastatic subclones result from the dispersal and adaptation of an initially non-metastatic parental clone. Therefore, a single-region sampling will not reflect the evolving architecture of a genomically heterogeneous landscape of mutations in ESCC tumors and the divergent complexity of this genomic heterogeneity among patients will complicate any promise of a simple genetic or epigenetic diagnostic signature in ESCC. We conclude that any potential for informative biomarker discovery in ESCC and targeted personalized therapies will require a deeper understanding of the functional biology of the ontogeny and phylogeny of the tumor heterogeneity.

Colour Doppler ultrasonography can be used to detect the changes of sacroiliitis and peripheral enthesitis in patients with ankylosing spondylitis during adalimumab treatment

OBJECTIVES

To investigate whether colour Doppler ultrasonography (CDUS) can be used to detect the effect of adalimumab on sacroiliitis and peripheral enthesitis in patients with ankylosing spondylitis (AS).

METHODS

AS patients (n=41) received 40 mg adalimumab every other week for 24 weeks. BASDAI, BASFI, CRP, MRI examinations of the sacroiliac joints (SIJs) and CDUS examinations of both SIJs and 10 peripheral entheseal sites were taken at baseline, week 12, and week 24. We scored the MR images by SPARCC method, recorded the resistive index (RI) value of SIJs and graded the blood signal on a semi quantitative 0-3 scale. We also scored lesions of peripheral entheses seen by CDUS. We analysed the associations between the results of CDUS and clinical indices and MRI data.

RESULTS

Significant reduction in mean CDUS score of SIJs and peripheral enthesitis and increase in mean RI value were observed in AS patients treated with adalimumab for 12 weeks and 24 weeks as compared with baseline (all p<0.05). The CDUS scores of SIJs and peripheral enthesitis positively related with clinical assessments (including BASDAI, BASFI, and CRP), while the RI value negatively related with them at all visits (all p<0.05). The results of CDUS also correlated well with the MRI data (all p<0.05) during adalimumab treatment in AS patients.

CONCLUSIONS

Our study found that CDUS could be used to detect the changes of sacroiliitis and peripheral enthesitis in AS patients under adalimumab therapy.

Accurate genotyping of hepatitis C virus through nucleotide sequencing and identification of new HCV subtypes in China population

Nucleotide sequencing of the phylogenetically informative region of NS5B remains the gold standard for hepatitis C virus (HCV) genotyping. Here we developed a new methodology for sequencing new NS5B regions to increase the accuracy and sensitivity of HCV genotyping and subtyping. The eight new primers were identified by scanning the full-length NS5B regions from 1127 HCV genomic sequences found in HCV databases. The ability of each pair of primers to amplify HCV subtypes was scored, and the new primers were able to amplify the NS5B region better than the previously used primers, therefore more accurately subtyping HCV strains. Sequencing the DNA amplified by the new primer pairs can specifically and correctly detect the five standard HCV subtypes (1a, 2a, 3b, 6a and 1b). We further examined patient samples and found that the new primers were able to identify HCV subtypes in clinical samples with high sensitivity. This method was able to detect all subtypes of HCV in 567 clinical samples. Importantly, three novel HCV subtypes (1b-2a, 1b-2k and 6d-6k) were identified in the samples, which have not been previous reported in China. In conclusion, sequencing the NS5B region amplified by the new NS5B primers is a more reliable method of HCV genotyping and a more sensitive diagnostic tool than sequencing using the previously described primers, and could identify new HCV subtypes. Our research is useful for clinical diagnosis, guidance of clinical treatment, management of clinical patients, and studies on the epidemiology of HCV.

Arterial flow regulator enables transplantation and growth of human fetal kidneys in rats

Here we introduce a novel method of transplanting human fetal kidneys into adult rats. To overcome the technical challenges of fetal-to-adult organ transplantation, we devised an arterial flow regulator (AFR), consisting of a volume adjustable saline-filled cuff, which enables low-pressure human fetal kidneys to be transplanted into high-pressure adult rat hosts. By incrementally withdrawing saline from the AFR over time, blood flow entering the human fetal kidney was gradually increased until full blood flow was restored 30 days after transplantation. Human fetal kidneys were shown to dramatically increase in size and function. Moreover, rats which had all native renal mass removed 30 days after successful transplantation of the human fetal kidney were shown to have a mean survival time of 122 days compared to 3 days for control rats that underwent bilateral nephrectomy without a prior human fetal kidney transplant. These in vivo human fetal kidney models may serve as powerful platforms for drug testing and discovery.