Comparative analysis of different nuclear transfer techniques to prevent the transmission of mitochondrial DNA variants

Prevention of mitochondrial DNA (mtDNA) diseases may currently be possible using germline nuclear transfer (NT). However, scientific evidence to compare efficiency of different NT techniques to overcome mtDNA diseases is lacking. Here, we performed four types of NT, including first or second polar body transfer (PB1/2T), maternal spindle transfer (ST) and pronuclear transfer (PNT), using NZB/OlaHsd and B6D2F1 mouse models. Embryo development was assessed following NT, and mtDNA carry-over levels were measured by next generation sequencing (NGS). Moreover, we explored two novel protocols (PB2T-a and PB2T-b) to optimize PB2T using mouse and human oocytes. Chromosomal profiles of NT-generated blastocysts were evaluated using NGS. In mouse, our findings reveal that only PB2T-b successfully leads to blastocysts. There were comparable blastocyst rates among PB1T, PB2T-b, ST and PNT embryos. Furthermore, PB1T and PB2T-b had lower mtDNA carry-over levels than ST and PNT. After extrapolation of novel PB2T-b to human in vitro matured (IVM) oocytes and in vivo matured oocytes with smooth endoplasmic reticulum aggregate (SERa) oocytes, the reconstituted embryos successfully developed to blastocysts at a comparable rate to ICSI controls. PB2T-b embryos generated from IVM oocytes showed a similar euploidy rate to ICSI controls. Nevertheless, our mouse model with non-mutated mtDNAs is different from a mixture of pathogenic and non-pathogenic mtDNAs in a human scenario. Novel PB2T-b requires further optimization to improve blastocyst rates in human. Although more work is required to elucidate efficiency and safety of NT, our study suggests that PBT may have the potential to prevent mtDNA disease transmission.

Ethnopharmacological importance and medical applications of Myrothamnus flabellifolius Welw. (Myrothamnaceae)-A review

ETHNOPHARMACOLOGICAL RELEVANCE

Myrothamnus flabellifolius Welw. (resurrection plant) is a desiccant-tolerant, woody, and shrubby plant. It is popularly used as a local medicinal herbal tea in South Africa, other Southern Africa nations, and Central Africa. M. flabellifolius is used in treating several ailments including epilepsy, mental disorder, cough, pain, stroke, shingles, diabetes, hypertension, wounds, asthma, kidneys and chest ailments.

AIM OF THIS REVIEW

This review focuses on the botanical description, distribution, conservation status, ethnobotany, chemistry and pharmacological properties of M. flabellifolius to spur further research that will promote its sustainable harvesting and commercialization.

MATERIAL AND METHODS

A literature search on diverse scientific databases, including Google, Google Scholar, Science Direct, PubMed, Scopus, theses, dissertations and ethnobotanical textbooks, were conducted.

RESULTS

The conducted search reveals that M. flabellifolius has many traditional uses that can be categorized into infectious diseases, Well-being, respiratory, inflammation, wound and kidney ailments. M. flabellifolius is a natural caffeine-free medicinal herbal tea reported to have antioxidant, anticancer, antiviral, antidiabetic and antimicrobial properties. Toxicological tests on M. flabellifolius were found scarce with gaps in genotoxicological and in vivo studies. Essential oils and isolated compounds were identified from M. flabellifolius with biological activities such as anticancer, antiinflammation, antimicrobial, antiarthritic, antiulcer, antioxidant and antiviral properties.

CONCLUSION

It is envisaged that the current review will add value to more scientific research on M. flabellifolius and enhance/promote the increased interest in the sustainable commercialization of M. flabellifolius herbal tea as well as lead to the validation of unverified ethnobotanical claims.

Adaptation of plants to high-calcium content kart regions: possible involvement of symbiotic microorganisms and underlying mechanisms

Rhizosphere microorganisms and endophytes can help their hosts absorb nutrients and regulate the levels of plant hormones. Moreover, they can modulate the expressions of host genes, assist hosts in eliminating reactive oxygen species (ROS) and secreting volatile organic compounds. Therefore, rhizosphere microorganisms and endophytes are considered as determinant factors driving processes involved in the growth of host plants. However, the physiological and ecological functions, as well as the molecular mechanism underlying the behavior of rhizosphere microorganisms and endophytes in their role in the adaptive capacity of host plants in the karstic high-calcium environment have not been systematically studied. This review summarizes the physiological and molecular mechanisms of rhizosphere microorganisms and endophytes which help host plants to adapt to various kinds of adverse environments. The adaptive capacities of plants growing in adverse environments, partly, or totally, depends on microorganisms co-existing with the host plants.

Association between Skeletal Muscle Strength and Dysphagia among Chinese Community-Dwelling Elderly Adults

OBJECTIVES

Swallowing disorder is a health burden for the elderly in China. This study aimed to investigate the prevalence of dysphagia and to test the association between skeletal muscle strength and swallowing problems among community-dwelling older adults.

DESIGN

A cross-sectional study.

SETTING

Community-dwelling Chinese elderly in China.

PARTICIPANTS

3361 adults aged 65 years or above were involved, among which 1740 (51.8%) were female, with average age of 72.64 (Standard deviation, SD=6.10) years old.

MEASUREMENTS

Handgrip strength (HGS) was used to evaluate skeletal muscle strength. Dysphagia assessment was performed using the Eating Assessment Tool-10 (EAT-10) and the 30mL water swallow test (WST). Binary logistic regression was used to evaluate the relationship between skeletal muscle strength and dysphagia, and covariates as age, gender, material status, etc. were adjusted.

RESULTS

The prevalence of dysphagia were 5.5% and 12.9%, screened by EAT-10 and 30mL WST respectively. Participants with dysphagia showed lower HGS (21.73 ± 9.20 vs. 25.66 ± 11.32, p<0.001, by EAT-10; 20.26 ± 9.88 vs. 26.22 ± 11.28, p<0.001, by WST). The adjusted model suggested that muscle strength is a protective factor for swallowing disorders (adjusted OR=0.974, 95%CI: 0.950-0.999, by EAT-10; adjusted OR=0.952, 95%CI: 0.933-0.972, by WST). Subgroup analyses of WST found the effects were significant among participants aged in 70-74 years group and ≥75 years group, rather than those aged under 70.

CONCLUSION

Dysphagia was significantly associated with skeletal muscle strength among the community-dwelling elderly population. Effective interventions should be taken to manage the decline of muscle strength for the older adults, especially early prevention before 70 years old.

Detection of hepatitis E virus genotypes 3 and 4 in donkeys in northern China

BACKGROUND

Hepatitis E virus (HEV) is the causative agent of acute self-limiting hepatitis in humans in developing countries. Hepatitis E virus RNA was first detected in donkeys in Spain, but little is known about the possible presence of HEV in donkeys in China.

OBJECTIVES

To investigate the prevalence of HEV in donkeys in northern China.

STUDY DESIGN

Investigation of the prevalence of HEV in donkeys using serological, molecular and phylogenetic approaches.

METHODS

A total of 401 donkey serum specimens were tested for serological and molecular detection of HEV via enzyme-linked immunosorbent assay and quantitative reverse transcription polymerase chain reaction. The amplified products were cloned in pMD18-T vector and sequenced. The alignment and phylogenetic analysis of partial HEV ORF2 genes were compared with the corresponding sequences of the obtained HEV representative strains.

RESULTS

Serological results showed that 49 donkeys (12.22%, 95% CI: 9.18-15.83%) were positive for anti-HEV-specific antibodies, and 17 donkeys (4.24%, 95% CI: 2.49-6.70%) were positive for HEV viral RNA. On the basis of sequence alignment and phylogenetic analysis, all isolated HEV strains belonged to genotype 3 (HEV-3) or HEV-4, sharing more than 76.2-96.3% identities with 67 other HEV representative strains of HEV-1 to HEV-8.

MAIN LIMITATIONS

Further studies about the prevalence of HEV in organs or faecal samples from donkeys are needed to evaluate the possible role of HEV reservoir and to determine the risk factors associated with the transmission of this zoonotic virus in donkeys in China.

CONCLUSIONS

This is the first report documenting the molecular analysis of donkey HEV strains worldwide and the serological evidence of HEV infection in donkeys in northern China. The results suggest that young donkeys are more susceptible to HEV infection compared with older donkeys. Further investigation is required to determine whether donkeys should be considered reservoirs for zoonotic HEV. The Summary is available in Chinese - see Supporting information.

Randomized phase III study of docetaxel plus bavituximab in previously treated advanced non-squamous non-small-cell lung cancer

Background

Bavituximab is a monoclonal antibody that targets phosphatidylserine in the presence of β2 glycoprotein 1 (β2GP1) to exert an antitumor immune response. This phase III trial determined the efficacy of bavituximab combined with docetaxel in patients with previously treated advanced non-small-cell lung cancer (NSCLC).

Patients and methods

Key eligibility criteria included advanced non-squamous NSCLC with disease progression after treatment with platinum-based doublet chemotherapy, evidence of disease control after at least two cycles of first-line therapy, presence of measurable disease, ECOG performance status 0 or 1, adequate bone marrow and organ function, and no recent history of clinically significant bleeding. Eligible patients were randomized 1 : 1 to receive up to six 21-day cycles of docetaxel plus either weekly bavituximab 3 mg/kg or placebo until progression or toxicity. The primary end point was overall survival (OS).

Results

A total of 597 patients were enrolled. Median OS was 10.5 months in the docetaxel + bavituximab arm and was 10.9 months in the docetaxel + placebo arm (HR 1.06; 95% CI 0.88-1.29; P = 0.533). There was no difference in progression-free survival (HR 1.00; 95% CI 0.82-1.22; P = 0.990). Toxicities were manageable and similar between arms. In subset analysis, among patients with high baseline serum β2GP1 levels ≥200 µg/ml, a nonsignificant OS trend favored the bavituximab arm (HR 0.82; 95% CI 0.63-1.06; P = 0.134). Among patients who received post-study immune checkpoint inhibitor therapy, OS favored the bavituximab arm (HR 0.46; 95% CI 0.26-0.81; P = 0.006).

Conclusions

The combination of bavituximab plus docetaxel is not superior to docetaxel in patients with previously treated advanced NSCLC. The addition of bavituximab to docetaxel does not meaningfully increase toxicity. The potential benefit of bavituximab observed in patients with high β2GP1 levels and in patients subsequently treated with immune checkpoint inhibitors requires further investigation.

Clinical trial number

NCT01999673.

Comparison of size-resolved hygroscopic growth factors of urban aerosol by different methods in Tianjin during a haze episode

Size-resolved hygroscopic growth factors of urban aerosol during a haze episode were measured using a Humidified Tandem Differential Mobility Analyzer (HTDMA) (g_m(RH)). These factors were also derived from size-resolved particulate chemical composition combined with the κ-Köhler theory (g_κ(RH)) and the thermodynamic model ISORROPIA-II running in forward mode (g_iso-f(RH)) and reverse mode (g_iso-r(RH)), respectively. In terms of agreement among these hygroscopic growth factors, g_κ(RH) matched g_m(RH) best, followed by g_iso-r(RH). In contrast, g_iso-f(RH) demonstrated a poorer agreement with g_m(RH). The good consistency among g_m(RH), g_κ(RH), and g_iso-r(RH) was because they only focus on the physical hygroscopic process, whereas g_iso-f(RH) contains not only the direct influence of relative humidity (RH) on particle size but also the influence of gaseous precursor on the particle chemical composition, which indirectly affects the hygroscopicity of the particles. In this sense, size-resolved g_κ(RH) and g_iso-r(RH) in a wide size range are more adequate to investigate the impact of RH on light scattering and aerosol radiative forcing. At RH = 80%, g_κ(RH) for accumulation mode particles was 1.30-1.45 on polluted days and higher than that on clean days (1.2-1.3). Whereas on both polluted and clean days, g_κ(RH) of ultrafine and coarse mode particles were generally lower than 1.25. The strong hygroscopicity of accumulation mode particles observed on polluted days can deteriorate visibility due to their high extinction efficiency.

The bHLH Protein Nulp1 is Essential for Femur Development Via Acting as a Cofactor in Wnt Signaling in Drosophila

Background:

The basic helix-loop-helix (bHLH) protein families are a large class of transcription factors, which are associated with cell proliferation, tissue differentiation, and other important development processes. We reported that the Nuclear localized protein-1 (Nulp1) might act as a novel bHLH transcriptional factor to mediate cellular functions. However, its role in development in vivo remains unknown.

Methods:

Nulp1 (dNulp1) mutants are generated by CRISPR/Cas9 targeting the Domain of Unknown Function (DUF654) in its C terminal. Expression of Wg target genes are analyzed by qRT-PCR. We use the Top-Flash luciferase reporter assay to response to Wg signaling.

Results:

Here we show that Drosophila Nulp1 (dNulp1) mutants, generated by CRISPR/Cas9 targeting the Domain of Unknown Function (DUF654) in its C terminal, are partially homozygous lethal and the rare escapers have bent femurs, which are similar to the major manifestation of congenital bent-bone dysplasia in human Stuve-Weidemann syndrome. The fly phenotype can be rescued by dNulp1 over-expression, indicating that dNulp1 is essential for fly femur development and survival. Moreover, dNulp1 overexpression suppresses the notch wing phenotype caused by the overexpression of sgg/GSK3β, an inhibitor of the canonical Wnt cascade. Furthermore, qRT-PCR analyses show that seven target genes positively regulated by Wg signaling pathway are down-regulated in response to dNulp1 knockout, while two negatively regulated Wg targets are up-regulated in dNulp1 mutants. Finally, dNulp1 overexpression significantly activates the Top-Flash Wnt signaling reporter.

Conclusion:

We conclude that bHLH protein dNulp1 is essential for femur development and survival in Drosophila by acting as a positive cofactor in Wnt/Wingless signaling.

Intensive vertical orientation Smith-Purcell radiation from the 2D well-array metasurface

We present an intensive vertical orientation Smith-Purcell radiation with the 2D well-array metasurface. It is shown that the moving electrons can induce three induced surface currents at the well-array metasurface, where a strong coupling among them takes place. The coupling significantly improves the radiated field intensity and shapes the radiation angle-distribution. The theoretical results show that the Smith-Purcell radiation's field intensity is 3 times larger than the one within a conventional grating structure with directional radiation at 90 degree. Therefore, much stronger intensity and more centralized directional radiation will provide a promising way to develop electron beam driven THz sources.

[Research progress of oral anticoagulants in patients with liver diseases]

Patients with liver disease are at an increased risk of both embolism and bleeding. The optimal anticoagulation strategy remains unclear when associated with venous thromboembolic disease. Moreover, currently approved oral anticoagulant drugs undergo metabolism and elimination in the liver with varying degrees of hepatic dysfunction. Thus, impaired liver function may lead to increased risk of bleeding, making anticoagulant therapy more intricate. This article summarizes the risk of bleeding and thrombosis in patients with liver disease, and the clinical research progress of oral anticoagulants in patients with liver disease to facilitate evidence for choosing oral anticoagulants therapy when required.

Five alternative splicing variants of the TYR gene and their different roles in melanogenesis in the Muchuan black-boned chicken

1. The TYR gene encodes tyrosinase, a multifunctional enzyme that is essential for melanin biosynthesis in melanocytes. This experiment involved the cloning and characterisation of the TYR gene in chicken. Five alternative splice variants were identified in the black feather bulb and designated as TYR-AS1, TYR-AS2, TYR-AS3, TYR-AS4 and TYR-AS5. 2. Among the 11 chicken tissues examined, the feather bulb, comb and skin showed higher levels of all TYR variants. All TYR variants were expressed at significantly different levels in black and white feather bulbs (P < 0.05) and may be involved in melanin formation in plumage. Only TYR-AS1, which plays an important role in muscle melanogenesis, was significantly differentially expressed between black and white muscle (P < 0.01). All TYR variants were expressed at significantly different levels in black and white skin (P < 0.01). 3. The mRNA expression levels of the 5 variants were closely associated with skin melanogenesis in the chicken. These findings provide new clues to the molecular mechanism of melanin formation in the Muchuan black-boned chicken.

[Visceral parasitic migration of liver: a clinicopathologic analysis of seven cases]

Objective: To investigate the clinical, radiological and pathological features of visceral parasitic migration of the liver. Methods: Seven cases of visceral parasitic migration of liver were identified at the Affiliated Drum Tower Hospital of Medical School of Nanjing University from January 2008 to July 2017. Clinical data, enhanced CT image and pathological features were analyzed, combining with literature review. Results: There were 5 male and 2 female patients. Five patients presented with abdominal pain or discomfort as the first symptom. Two patients were admitted to the hospital for physical examination with liver nodule. Blood eosinophils were mildly to moderately increased in 4 cases. Enhanced CT showed the liver irregular beaded nodules that showed no significant enhancement of arterial phase. Mild enhancement of round lesions (ring lesion) was seen in a few cases before surgery. By histopathology, the lesions showed central geographic necrosis, surrounded by epithelioid granuloma and inflammatory cell bands. A large number of eosinophils and scattered multinucleated giant cells were found, especially at the peripheral of the lesion. Charcot-Leyden crystals were present in all case and parasitic migrans was found in one case. Conclusions: Visceral parasitic migration of liver is a rare liver disease and is easily misdiagnosed as other benign or malignant liver tumors. Combining clinical data, enhanced CT images and pathological examination can improve the preoperative and postoperative diagnosis of the disease.

[Clinical results of Mei mini maze procedure for atrial fibrillation patients with previously failed catheter ablation]

Objective: To evaluate the efficacy of Mei mini maze procedure for treating atrial fibrillation (AF) patients with previously failed catheter ablation. Methods: Between August 2010 and May 2016, 48 AF (8 proximal AF, 15 persistent AF and 25 long-standing persistent AF) patients (29 males, 19 females, mean age: (62.5±7.3) years old) with previously 1-3 failed catheter ablation results were treated with Mei mini maze procedure in our department. Under thoracoscopic assistance, the procedure was performed through three ports on left chest wall, pulmonary vein isolation and ablations of the roof and posterior wall of left atrium was made by bipolar radiofrequency ablation. Ganglionic plexus ablation was made by the ablation pen. Left atrial appendage was excluded. Patients were followed at outpatient clinic and per telephone. Electrocardiogram, CT and echocardiography examinations were performed at 1, 3, 6 and 12 months post operation. The success rate of the procedure was analyzed by Kaplan-Meier curves and evaluated by the log-rank test. Results: Mean AF history was (8.1±6.3) years and left atria dimension was (44.1±6.2) mm in this patient cohort. All procedures were performed successfully in these 48 patients. Pericardial adhesions were dissected in 21 patients. Durations of the procedures were (142.3±35.6) minutes.There were no serious complications. The hospital stay was (9.3±1.8) days. Sinus rhythm was documented in 44 patients (91.7%) at discharge. The mean follow-up duration was (28.0±17.2) months. Thirty-eight patients (82.6%) were in sinus rhythm. There was no stroke, thrombus in the left atrium and stenosis of pulmonary vein during the follow-up. Sinus rhythm was achieved in 7 out of 8 paroxysmal AF patients, in 31 out of 38 non-paroxysmal AF patients, and in 13 out of 15 persistent AF patients. Kaplan-Meier curve showed that the success rate in the long-standing persistent AF group was lower than in the other two groups, but there was no statistical difference. Conclusions: Mei mini maze procedure has a high success rate for AF patients with previously failed catheter ablation history, which could completely isolate the bilateral pulmonary vein and left atrial posterior wall with good quality and integrity of ablation line, and left atrial appendage is also resected during the procedure.

Real-time observation of leukocyte-endothelium interactions in tissue-engineered blood vessel

Human cell-based 3D tissue constructs play an increasing role in disease modeling and drug screening. Inflammation, atherosclerosis, and many autoimmune disorders involve the interactions between immune cells and blood vessels. However, it has been difficult to image and model these interactions under realistic conditions. In this study, we fabricated a perfusion and imaging chamber to allow the real-time visualization of leukocyte perfusion, adhesion, and migration inside a tissue-engineered blood vessel (TEBV). We monitored the elevated monocyte adhesion to the TEBV wall and transendothelial migration (TEM) as the TEBV endothelium was activated by the inflammatory cytokine TNF-α. We demonstrated that treatment with anti-TNF-α or an NF-kB signaling pathway inhibitor would attenuate the endothelium activation and reduce the number of leukocyte adhesion (>74%) and TEM events (>87%) close to the control. As the first demonstration of real-time imaging of dynamic cellular events within a TEBV, this work paves the way for drug screening and disease modeling in TEBV-associated microphysiological systems.

Wastewater management approach in an industrial park

Many industrial parks adopt a two-tier wastewater management framework whereby tenants and the park are required to build satellite and centralized wastewater treatment facilities, respectively. Due to the diversity of industrial wastewaters, the treatment process scheme in the public centralized wastewater treatment plant (WWTP) may not suit the characteristics of all effluents discharged from the tenants. In consideration of varying wastewater biodegradability, the treatment scheme in a centralized WWTP is advised to install two series of treatment processes. In detail, various effluents from the tenants shall be commingled according to their levels of biodegradability. For the non-biodegradable streams, advanced oxidation processes shall be applied in addition to biological treatments. To facilitate the grouping of effluents, each effluent will be evaluated for its biodegradability. An analytical protocol derived from OECD standard (TG302B) was developed and found effective for biodegradability assessment. A case study is described in this paper to showcase the methodology.

Pinewood nematode infection alters root mycoflora of Pinus tabulaeformis Carr

AIMS

This study investigates pinewood nematode's impacts on root mycoflora of Pinus tabulaeformis.

METHODS AND RESULTS

The biomass, colonization rate, community structure and diversity of root-associated fungi were investigated in pinewood nematode-infected and nematode-noninfected P. tabulaeformis. The results indicated that the roots of P. tabulaeformis were colonized highly by root-associated fungi, mainly ectomycorrhizal fungi (ECMF) and dark septate endophytes. Infection of pinewood nematode was associated with a significant (P < 0·05) decrease in root colonization rates by ECMF, dark septate endophytes and total hyphae, as well as in fungal biomass in the roots. Illumina MiSeq sequences of tagged amplicons of 18S rDNA region revealed Basidiomycota (65·70%) and Ascomycota (34·14%) as the dominant root-associated fungi in roots of P. tabulaeformis. Among the detected operational taxonomic units (OTUs), ECMF and dark septate endophytes exhibited a higher relative abundance in trees infected by pinewood nematode compared with noninfected ones.

CONCLUSIONS

The infection of pinewood nematode altered the composition and OTU abundance of root-associated fungi community in P. tabulaeformis roots with a decrease in the biomass, species richness and diversity of root-associated fungi, as well as in the colonization rates and abundance of ECMF and dark septate endophytes.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study is an important contribution for better understanding the interaction between pine wilt disease and root-associated fungi.

Comparative cytotoxicity and apoptotic pathways induced by nanosilver in human liver HepG2 and L02 cells

Silver nanoparticles are used in many commercial products in daily life. Exposure to nanosilver has hepatotoxic effects in animals. This study investigated the cytotoxicity associated with polyvinylpyrrolidone-coated nanosilver (23.44 ± 4.92 nm in diameter) exposure in the human hepatoma cell line (HepG2) and normal hepatic cell line (L02), and the molecular mechanisms induced by nanosilver in HepG2 cells. Nanosilver, in doses of 20-160 μg mL^-1 for 24 and 48 h, reduced cell viability in a dose- and time-dependent manner and induced cell membrane leakage and mitochondria injury in both cell lines; these effects were more pronounced in HepG2 cells than in L02 cells. Intracellular oxidative stress was documented by reactive oxygen species (ROS) being generated in HepG2 cells but not in L02 cells, an effect possibly due to differential uptake of nanosilver by cancer cells and normal cells. In HepG2 cells, apoptosis was documented by finding that ROS triggered a decrease in mitochondrial membrane potential, an increase in cytochrome c release, activation of caspase 3 and caspase 9, and a decrease in the ratio of Bcl-2/Bax. Furthermore, nanosilver activated the Fas death receptor pathway by downregulation of nuclear factor-κB and activation of caspase 8 and caspase 3. These results suggest that apoptosis induced by nanosilver in HepG2 cells is mediated via a mitochondria-dependent pathway and the Fas death receptor pathway. These findings provide toxicological and mechanistic information that can help in assessing the effects of nanosilver in biological systems, including the potential for anticancer activities.

Abstract GS1-05: Tandem duplicator phenotypes define 50% of triple negative breast cancers

Background. We recently discovered a unique chromotype, the Tandem Duplicator Phenotype (TDP), characterized by hundreds of somatic tandem duplications (TDs) scattered throughout the genome of a large percentage of triple negative breast cancers (TNBCs). Importantly, we observed that the TDP associates with a better response to cisplatin therapy in vitro and in vivo, suggesting that it is a tractable and quantitative biomarker of response to platinum-based therapy. Here, we expand on our initial findings by analyzing Whole-Genome (WG) sequences of over 2,700 tumors.

Methods. TD coordinates from WG sequences relative to 2717 tumors were assembled from over 30 independent studies representing several cancer types, including 254 TNBCs. WG sequencing of mouse breast tumors was carried out using standard Illumina protocols. The number, distribution and span-size of somatic TDs from a training set of 992 tumors were used to develop a TDP classifier that identifies highly recurrent but clearly distinct TDP profiles. The TDP classifier was then applied to the remaining tumor sequences. WG mutation and copy number datasets were investigated to identify the genetic drivers associated with each TDP profile, and the genomic consequences of different TDPs were evaluated through identification of genomic hotspots for gene duplication and transection.

Results. We describe six different TDPs featuring distinct TD span size distributions, with peaks at 10Kb (group 1), 300Kb (group 2) and 3Mb (group 3), or different combinations of these (mix12, mix13 and mix23). More than half of all TNBC display a TDP. Of these, 55% classify as group 1, 14% as group 2 and 15% as group mix12. Whereas all TDP groups show a higher TP53 mutation rate compared to non-TDP tumors, each TDP profile is characterized by specific additional gene perturbations, with loss of BRCA1 occurring in groups 1, mix12 and mix13; CCNE1 amplification in group 2; and CDK12 mutations in group mix23. We show that different TDPs are subject to the perturbation of specific oncogenic networks resulting from the duplication of oncogenes by larger TDs (&gt;300Kb) or the disruption of tumor suppressors via double transections by shorter TDs (10Kb). Indeed, tumor suppressor genes such as PTEN, RB1 and MLL3 are frequently disrupted by TDs in TNBC TDP group 1 tumors, whereas TNBC TDP group 2 tumors commonly feature duplication of oncogenes such as MYC and MALAT1. Finally, through WG analyses of 18 mouse models (GEMMs) of breast cancer, we provide the first mechanistic evidence of the driving role of conjoint loss of TP53 and BRCA1, but not of BRCA2, in inducing the TDP group 1 profile.

Conclusions. Our study shows a definitive genetic induction of one specific form of TDP (group 1) characterized by 10kb TD span. Different TDP profiles are characterized by alternative somatic genetic origins but always couple with disruptive TP53 mutations. The consequences of the massive TD formation in TDP TNBCs suggest a systems strategy to tumor induction involving heterogeneous combinations of oncogenes and tumor suppressors. That these TDP forms, accounting for ˜50% of TNBC, are associated with significant sensitivity to cisplatin suggest that this chromotype may identify TNBC patients who would benefit from upfront platinum-based chemotherapy.

Citation Format: Liu ET, Menghi F, Barthel F, Yadav V, Tang M, Ji B, Carter G, Jonkers J, Verhaak R. Tandem duplicator phenotypes define 50% of triple negative breast cancers [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr GS1-05.

Galaxy growth in a massive halo in the first billion years of cosmic history

According to the current understanding of cosmic structure formation, the precursors of the most massive structures in the Universe began to form shortly after the Big Bang, in regions corresponding to the largest fluctuations in the cosmic density field. Observing these structures during their period of active growth and assembly-the first few hundred million years of the Universe-is challenging because it requires surveys that are sensitive enough to detect the distant galaxies that act as signposts for these structures and wide enough to capture the rarest objects. As a result, very few such objects have been detected so far. Here we report observations of a far-infrared-luminous object at redshift 6.900 (less than 800 million years after the Big Bang) that was discovered in a wide-field survey. High-resolution imaging shows it to be a pair of extremely massive star-forming galaxies. The larger is forming stars at a rate of 2,900 solar masses per year, contains 270 billion solar masses of gas and 2.5 billion solar masses of dust, and is more massive than any other known object at a redshift of more than 6. Its rapid star formation is probably triggered by its companion galaxy at a projected separation of 8 kiloparsecs. This merging companion hosts 35 billion solar masses of stars and has a star-formation rate of 540 solar masses per year, but has an order of magnitude less gas and dust than its neighbour and physical conditions akin to those observed in lower-metallicity galaxies in the nearby Universe. These objects suggest the presence of a dark-matter halo with a mass of more than 100 billion solar masses, making it among the rarest dark-matter haloes that should exist in the Universe at this epoch.

[Analysis of 2 204 stillbirths in 11 hospitals of Guangdong province]

Objective: To analyze the incidence and causes of stillbirth in 11 hospitals of Guangdong province, and to explore the appropriate interventions. Methods: Clinical data of stillbirth in 11 hospitals of Guangdong province were collected from January 2014 to December 2016. The gestational weeks, causes, maternal conditions and other factors were analyzed. Results: (1) From 2014 to 2016, 103 472 newborns were delivered in the 11 hospitals, and the number of stillbirth was 2 204, with the incidence of 2.13%. Among them, 0.71%(738/103 472) was therapeutic induction, 1.42%(1 066/103 472) was natural stillbirth. At different gestational age (<28 weeks, 28-<37 weeks and ≥37 weeks), the incidence of stillbirth was 55.63% (1 226/2 204), 28.45% (627/2 204) and 15.92% (351/2 204), respectively, with statistically significant difference (P<0.01). (2) For stillbirth<28 weeks, the first reason was therapeutic induction, accounting for 53.34% (654/1 226). For stillbirth during 28-37 weeks, pre-eclampsia was the major cause, accounting for 40.67% (255/627). And for full-term stillbirth, the causes were umbilical cord factors (19.37%, 68/351), abnormal labor (17.09%, 60/351). (3) In all the stillbirth cases, the incidence of fetal growth restriction (FGR) <28 weeks was significantly higher than that during 28-37 weeks [23.49% (288/1 226) vs 18.02% (113/627) , P<0.01]. (4) The stillbirth rate during labor was significantly higher in women ≥35 years old than in younger women [63.88% (191/299) vs 36.12% (108/299) ; χ(2)=9.346, P=0.000]. For the causes of stillbirth during labor, the incidence of severe maternal obstetrical complications [61.11% (33/54) vs 38.89% (21/54) ; χ(2)=3.323, P=0.002], abnormal labor [65.82% (52/79) vs 34.18% (27/79) ; χ(2)=4.067, P=0.001] and abnormal fetal position [66.63% (26/39) vs 33.37% (13/39) ; χ(2)=3.002, P=0.013] were higher in women ≥35 years old than in younger women. (5) Cesarean section during labor accounted for 33.77% (101/299) of stillbirth, including 76 cases of emergency cesarean section or converted to cesarean section during labor. Conclusions: (1) The incidence of stillbirth in the 11 hospitals is high, and the causes are different at different gestational ages, therefore, different interventions are needed to reduce the incidence in different gestational weeks. Supervision of therapeutic induction should be strengthened <28 gestational weeks; standard management of pregnancy might decrease the occurrence of natural death ≥28 weeks. (2) Attention should be paid to fetal body weight during pregnancy, especially FGR. (3) The stillbirth rate is high in elderly pregnant women, so it is important to strengthen the management of the elderly pregnant women.

Genetic variation in the MITF promoter affects skin colour and transcriptional activity in black-boned chickens

1. Microphthalmia-associated transcription factor (MITF) plays a pivotal role in melanocyte development by regulating the transcription of major pigmentation enzymes (e.g. TYR, TYRP1 and DCT). A single-nucleotide polymorphism (SNP), c.-638T>C, was identified in the MITF promoter, and genotyping of a population (n = 426) revealed that SNP c.-638T>C was associated with skin colour in black-boned chickens. 2. Individuals with genotypes CC and TC exhibited greater MTIF expression than those with genotype TT. Luciferase assays also revealed that genotype CC and TC promoters had higher activity levels than genotype TT. Expression of melanogenesis-related gene (TYR) was higher in the skin of chickens with the CC and CT genotype compared to TT chickens (P < 0.05). 3. Transcription factor-binding site analyses showed that the c.-638C allele contains a putative binding site for transcription factor sterol regulatory element-binding transcription factor 2, aryl hydrocarbon receptor nuclear translocator, transcription factor binding to IGHM enhancer 3 and upstream transcription factor 2. In contrast, the c.-638T allele contains binding sites for Sp3 transcription factor and Krüppel-like factor 1. 4. It was concluded that MITF promoter polymorphisms affected chicken skin colour. SNP c.-638T>C could be used for the marker-assisted selection of skin colour in black-boned chicken breeding.

The differentiation of beige adipocyte in pericardial and epicardial adipose tissues induces atrial fibrillation development

OBJECTIVE

Growing evidence has identified that excessive accumulation of pericardial adipose tissues (PAT) and epicardial adipose tissues (EAT) is associated with atrial fibrillation (AF) development. Moreover, beige adipocytes, present in PAT and EAT, have been proved beneficial in consumption of fatty acid and promotion of weight lose by nonshivering thermogenesis. The objective of this prospective, observational study was to reveal the potential association between beige adipocytes and AF development.

PATIENTS AND METHODS

Fat tissues from subcutaneous adipose tissue (SAT), PAT and EAT were obtained from 70 AF and 30 sinus rhythm patients. Hematoxylin and eosin (H&E) staining were performed to analyze morphological changes in fat tissues. Real-time PCR was performed to identify mRNA expression of unique uncoupling protein-1 (UCP-1). Western blotting and immunohistochemistry (IHC) were performed to determine protein expression of UCP-1.

RESULTS

Our results indicated that pericardial and epicardial adipocytes in AF patients demonstrated white-like change tendency and had lower expression of UCP-1 when compared to sinus rhythm patients. Additionally, the decrease of UCP-1 mRNA expression in PAT and EAT, together with LA enlargement, were independent risk factors of AF. Further, UCP-1 mRNA expression in EAT, but not in PAT, have a significant correlation with LA diameter. The function of nonshivering thermogenesis in PAT and EAT was impaired in AF patients, and this dysfunction in EAT had a great correlation with LA dilation.

CONCLUSIONS

Our data provide a new therapeutic target for LA remodeling and AF treatment.

α2-adrenoceptor-mediated inhibition in the central amygdala blocks fear-conditioning

The central amygdala is critical for the acquisition and expression of fear memories. This region receives a dense innervation from brainstem noradrenergic cell groups and has a high level of α₂-adrenoceptor expression. Using whole-cell electrophysiological recordings from rat brain slices, we characterise the role of pre-synaptic α₂-adrenoceptor in modulating discrete inhibitory and excitatory connections within both the lateral and medial division of the central amygdala. The selective α₂-adrenoceptor agonist clonidine blocked the excitatory input from the pontine parabrachial neurons onto neurons of the lateral central amygdala. In addition, clonidine blocked inhibitory connections from the medial paracapsular intercalated cell mass onto both lateral and medial central amygdala neurons. To examine the behavioural consequence of α₂-adrenoceptor-mediated inhibition of these inputs, we infused clonidine into the central amygdala prior to contextual fear-conditioning. In contrast to vehicle-infused rats, clonidine-infused animals displayed reduced levels of freezing 24 hours after training, despite showing no difference in freezing during the training session. These results reveal a role for α₂-adrenoceptors within the central amygdala in the modulation of synaptic transmission and the formation of fear-memories. In addition, they provide further evidence for a role of the central amygdala in fear-memory formation.

[Acute toxicity and bio-distribution of silver nitrate and nano-silver with different particle diameters in rats]

Objective: To explore the acute toxic effect and the cumulative target organ of silver nitrate and nano-silver with two different particle diameters in rats. Methods: Thirty-six adult SD rats were divided into small particle size nano-silver group (SNS), large particle size nano-silver group (LNS), silver nitrate group (SN), and control group (C) according to the random number table, with 9 rats in each group. The rats of the four groups were respectively injected with 10 mg/mL nano-silver solution (particle diameter of 20 nm, prepared by saline) in silver dose of 30 mg/kg by tail vein for once, 10 mg/mL nano-silver solution (particle diameter of 100 nm, prepared by saline) in silver dose of 30 mg/kg, 1.67 mg/mL silver nitrate solution (prepared by glucose solution) in silver dose of 3 mg/kg, and 30 mg/mL polyvinylpyrrolidone solution (prepared by saline) in dose of 90 mg/kg. (1) Toxicity test. The general observation was performed within 14 days after injection, and the deviation between value of body mass before injection and each of that on post injection day (PID) 1, 7, and 14 were respectively recorded. On PID 1, 7, and 14, 3 rats of each group were harvested for determination of serum content of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total protein, and albumin by fully automatic biochemical analyzer. Then the rats were sacrificed immediately, and heart tissue, liver tissue, spleen tissue, lung tissue, kidney tissue, and brain tissue were collected to calculate the organ coefficient. Organ samples with obvious changes in organ coefficient were collected for histopathological observation by HE staining, with 3 samples in each group at each time point. (2) Bio-distribution. The specimens of heart, liver, spleen, lung, and kidney of rats from groups SNS, LNS, and SN were collected for detection of silver content by inductively coupled plasma mass spectrometry, with 3 samples in each group at each time point. Data were processed with analysis of variance of factorial design, LSD test, and Dunnett's T3 test. Results: (1) The general condition of rats in groups C and SN after injection were normal. The state of rats of groups SNS and LNS was poor with black secretion in the eye and other phenomena on PID 1, which recovered from PID 3 on. (2) The deviations between values of body mass before injection and that on PID 14 in rats of groups LNS and SN were significantly decreased as compared with deviation of group C (with P values below 0.01), but deviation of group SNS was not significantly changed (P>0.05). The deviations between values of body mass before injection and each of that on PID 1 and 7 in rats in the other three groups were similar to those in group C (with P values above 0.05). (3) Compared with those in group C, the serum content of total protein of rats in group SN on PID 1 was significantly decreased, and liver coefficient was significantly increased (with P values below 0.05). On PID 1, the serum content of ALT of rats in group LNS was (61.0±8.7) U/L, which was significantly higher than that in group C [(40.0±4.6) U/L, P<0.01]. Compared with those in group C [(126.0±3.5) U/L and 4.05±0.23], the serum content of AST of rats in groups SNS and LNS on PID 1[(249.7±107.2) and (237.0±38.3) U/L] was significantly increased, and liver coefficients (3.50±0.38 and 3.31±0.07) were significantly decreased, with P values below 0.05. Compared with those in group C [(69.2±4.8) U/L and 4.32±0.39], the serum content of AST of rats in groups SNS and LNS on PID 7 [(181.0±51.5) and (167.7±16.5) U/L] was also significantly increased, and liver coefficients (3.55±0.18 and 3.62±0.21) were also significantly decreased, P<0.05 or P<0.01. On PID 14, the four liver biochemical indexes in serum and all organ coefficients of rats in the other three groups were similar to those in group C (with P values above 0.05). (4) The liver of rats in group SN had slight degeneration on PID 1, the liver cells around the central vein of liver of rats in group SNS had slight degeneration on PID 7, and the liver cells got severely eosinophilic degeneration in liver of rats in group LNS on PID 7. There was no significant pathological change in the liver of rats in each group at the rest time points. (5) The silver content of lung and kidney in rats of group SNS on PID 1, that of spleen and kidney in rats of group LNS on PID 1, and that of heart and kidney in rats of groups LNS and SNS on PID 7 was significantly less than that of group SN (with P values below 0.05). The silver content of liver and spleen in rats of group SNS on PID 14 was significantly more than that of group SN (with P values below 0.05). Compared with that of group SN, the silver content of lung on PID 1 and liver on PID 7 in rats of group LNS was significantly increased (with P values below 0.05). On PID 14, there was no significant change in the silver content of all organs of rats between group SN and group LNS (with P values above 0.05). The silver content of heart, lung, and kidney on PID 1 and heart on PID 7 in rats of group LNS was significantly more than that of group SNS (with P values below 0.05). On PID 14, the silver content of each organ of rats in group SNS was close to that in group LNS (with P values above 0.05). Conclusions: Silver nitrate and nano-silver with two different particle diameters have a short acute toxic effect on the liver of rats, and the liver has certain ability of self-healing. Nano-silver is mainly accumulated in the liver. The distribution of nano-silver with large particle diameter in organs is more widely than that of nano-silver with small particle diameter.

Enhanced THz Smith-Purcell radiation based on the grating grooves with holes array

Smith-Purcell radiation is emitted when an electron passes above the surface of a metallic grating. Its mechanism can be explained with Huygens' principle by the radiation of a moving oscillating dipole, which is formed by the moving charge and its image in the metallic grating. Here, an alternative way is presented to enhance the THz Smith-Purcell radiation. By drilling a hole in the fins of a grating as an effective electron channel, the oscillation dipole happens in two dimensions here, instead of one dimension. As a result, the Smith-Purcell radiation power is ten times more than the case in which the electron passes very close to the grating surface. This method is expected to improve the efficiency of the devices which are based on the Smith-Purcell radiation.