The aim of this current study was to investigate the expression of the tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) and its receptor fibroblast growth factor-inducible 14 (Fn14) in human malignant ovarian tumors, and test TWEAK’s potential role on tumor progression in cell models in-vitro. Using immunohistochemistry (IHC), we found that TWEAK and its receptor Fn14 were expressed in human malignant ovarian tumors, but not in normal ovarian tissues or in borderline/benign epithelial ovarian tumors. High levels of TWEAK expression was detected in the majority of malignant tumors (36 out of 41, 87.80%). Similarly, 35 out of 41 (85.37%) malignant ovarian tumors were Fn14 positive. In these malignant ovarian tumors, however, TWEAK/Fn14 expression was not corrected with patients’ clinical subtype/stages or pathological features. In vitro, we demonstrated that TWEAK only inhibited ovarian cancer HO-8910PM cell proliferation in combination with tumor necrosis factor-α (TNF-α), whereas either TWEAK or TNF-α alone didn’t affect HO-8910PM cell growth. TWEAK promoted TNF-α production in cultured THP-1 macrophages. Meanwhile, conditioned media from TWEAK-activated macrophages inhibited cultured HO-8910PM cell proliferation and invasion. Further, TWEAK increased monocyte chemoattractant protein-1 (MCP-1) production in cultured HO-8910PM cells to possibly recruit macrophages. Our results suggest that TWEAK/Fn14, by activating macrophages, could be ovarian tumor suppressors. The unique expression of TWEAK/Fn14 in malignant tumors indicates that it might be detected as a malignant ovarian tumor marker.
This study aimed to analyze the volatile chemical profile of Longjing tea, and further develop a prediction model for aroma quality of Longjing tea based on potent odorants. A total of 21 Longjing samples were analyzed by headspace solid phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). Pearson’s linear correlation analysis and partial least square (PLS) regression were applied to investigate the relationship between sensory aroma scores and the volatile compounds. Results showed that 60 volatile compounds could be commonly detected in this famous green tea. Terpenes and esters were two major groups characterized, representing 33.89% and 15.53% of the total peak area respectively. Ten compounds were determined to contribute significantly to the perceived aroma quality of Longjing tea, especially linalool (0.701), nonanal (0.738), (Z)-3-hexenyl hexanoate (−0.785), and β-ionone (−0.763). On the basis of these 10 compounds, a model (correlation coefficient of 89.4% and cross-validated correlation coefficient of 80.4%) was constructed to predict the aroma quality of Longjing tea. Summarily, this study has provided a novel option for quality prediction of green tea based on HS-SPME/GC-MS technique.
Partial least square (PLS) regression; Green tea; Headspace solid phase microextraction (HS-SPME); Volatile profile; Quality prediction
AIM: To analyze the correlation of treatment method with the outcome of all the hepatic metastatic melanoma (HMM) patients from our hospital.
METHODS: There were altogether nine cases of HMM that had been treated in the PUMCH hospital during the past 25 years, from December 1984 to February 2010. All of the cases developed hepatic metastasis from primary cutaneous melanoma. A retrospective review was performed on all the cases in order to draw informative conclusion on diagnosis and treatment in correlation with the prognosis. Clinical features including symptoms, signs, blood test results, B-ultrasound and computed tomography (CT) imaging characteristics, and pathological data were analyzed in each case individually. A simple comparison was made on case by case basis instead of performing statistical analysis since the case numbers are low and patients were much diversified in each item that has been analyzed. Literatures on this subject were reviewed in order to draw a safe conclusion and found to be supportive to our finding in a much broad scope.
RESULTS: There are six males and three females whose ages ranged 39-74 years old with an average of 58.8. Patients were either with or without symptoms at the time of diagnosis. The liver function and tumor marker exam were normal in all but one patient. The incidence of HMM does not affect liver function and was not related to virus infection status in the liver. Most of these HMM patients were also accompanied by the metastases of other locations, including lung, abdominal cavity, and cervical lymph nodes. Ultrasound examinations showed lesions ranging 2-12 cm in diameter, with no- or low-echo peripheral areola. Doppler showed blood flow appeared inside some tumors as well as in the surrounding area. CT image demonstrated low density without uniformed lesions, characterized with calcification in periphery, and enhanced in the arterial phase. Contrast phase showed heterogeneous enhancement, with a density higher than normal liver tissue, which was especially apparent at the edge. Patients were treated differently with following procedures: patients #1, #6 and #8 were operated with hepatectomy with or without removal of primary lesion, and followed by comprehensive biotherapy/chemotherapy; patient #9 received hepatectomy only; patient #2 received bacille calmette-guerin treatment only; patient #7 had Mile’s surgery but no hepatectomy; and patients #3, #4 and #5 had supportive treatment without specific measurement. The patients who had resections of metastatic lesions followed by post-operative comprehensive therapy have an average survival time of 30.7 mo, which is much longer than those did not receive surgery treatment (4.6 mo). Even for the patient receiving a resection of HMM only, the post-operative survival time was 18 mo at the time we reviewed the data. This patient and the patient #6 are still alive currently and subjected to continue following up.
CONCLUSION: Surgical operation should be first choice for HMM treatment, and together with biotherapy/chemotherapy, hepatectomy is likely to bring better prognosis.
Malignant melanoma; Hepatic metastatic tumor; Hepatectomy; Hepatic metastatic melanoma; Prognosis; Biotherapy; Chemotherapy
Ribonucleotide reductase (RR) is a crucial enzyme in de novo DNA synthesis, where it catalyses the rate determining step of dNTP synthesis. RRs consist of a large subunit called RR1 (α), that contains two allosteric sites and one catalytic site, and a small subunit called RR2 (β), which houses a tyrosyl free radical essential for initiating catalysis. The active form of mammalian RR is an αnβm hetero oligomer. RR inhibitors are cytotoxic to proliferating cancer cells. In this brief review we will discuss the three classes of RR, the catalytic mechanism of RR, the regulation of the dNTP pool, the substrate selection, the allosteric activation, inactivation by ATP and dATP, and the nucleoside drugs that target RR. We will also discuss possible strategies for developing a new class of drugs that disrupts the RR assembly.
ribonucleotide reductase; gemcitabine; clofarabine; cladrabine; P6; P7; Cyc 10; dATP; ATP; allosteric regulation; specificity cross-talk; nucleotides
Two atmospheric circulation systems, the mid-latitude Westerlies and the Asian summer monsoon (ASM), play key roles in northern-hemisphere climatic changes. However, the variability of the Westerlies in Asia and their relationship to the ASM remain unclear. Here, we present the longest and highest-resolution drill core from Lake Qinghai on the northeastern Tibetan Plateau (TP), which uniquely records the variability of both the Westerlies and the ASM since 32 ka, reflecting the interplay of these two systems. These records document the anti-phase relationship of the Westerlies and the ASM for both glacial-interglacial and glacial millennial timescales. During the last glaciation, the influence of the Westerlies dominated; prominent dust-rich intervals, correlated with Heinrich events, reflect intensified Westerlies linked to northern high-latitude climate. During the Holocene, the dominant ASM circulation, punctuated by weak events, indicates linkages of the ASM to orbital forcing, North Atlantic abrupt events, and perhaps solar activity changes.
Biocatalytic processes often require a full recycling of biocatalysts to optimize economic benefits and minimize waste disposal. Immobilization of biocatalysts onto particulate carriers has been widely explored as an option to meet these requirements. However, surface properties often affect the amount of biocatalysts immobilized, their bioactivity and stability, hampering their wide applications. The aim of this work is to explore how immobilization of lipases onto magnetite nanoparticles affects their biocatalytic performance under carefully controlled surface modification.
Magnetite nanoparticles, prepared through a co-precipitation method, were coated with alkyl silanes of different alkyl chain lengths to modulate their surface hydrophobicity. Candida rugosa lipase was then directly immobilized onto the modified nanoparticles through hydrophobic interaction. Enzyme activity was assessed by catalytic hydrolysis of p-nitrophenyl acetate. The activity of immobilized lipases was found to increase with increasing chain length of the alkyl silane. Furthermore, the catalytic activities of lipases immobilized on trimethoxyl octadecyl silane (C18) modified Fe3O4 were a factor of 2 or more than the values reported from other surface immobilized systems. After 7 recycles, the activities of the lipases immobilized on C18 modified nanoparticles retained 65%, indicating significant enhancement of stability as well through hydrophobic interaction. Lipase immobilized magnetic nanoparticles facilitated easy separation and recycling with high activity retaining.
The activity of immobilized lipases increased with increasing alkyl chain length of the alkyl trimethoxy silanes used in the surface modification of magnetite nanoparticles. Lipase stability was also improved through hydrophobic interaction. Alkyl silane modified magnetite nanoparticles are thus highly attractive carriers for enzyme immobilization enabling efficient enzyme recovery and recycling.
Head and neck squamous cell carcinoma (HNSCC) is usually fatal, and innovative approaches targeting growth pathways are necessary to effectively treat this disease. Both the epidermal growth factor receptor (EGFR) and the hepatocyte growth factor (HGF)/c-Met pathways are overexpressed in HNSCC and initiate similar downstream signaling pathways. c-Met may act in consort with EGFR and/or be activated as a compensatory pathway in the presence of EGFR blockade.
Expression levels of EGFR and c-Met were determined by Western analysis in HNSCC cell lines and correlated with anti-tumor responses to inhibitors of these pathways.
Combining the c-Met inhibitor PF2341066 with the EGFR inhibitor gefitinib abrogated HNSCC cell proliferation, invasion and wound healing significantly more than inhibition of each pathway alone in HNSCC cell lines. When both HGF and the EGFR ligand, transforming growth factor-alpha (TGF-α), were present in vitro, P-AKT and P-MAPK expression were maximally inhibited by targeting both EGFR and c-Met pathways, suggesting that c-Met or EGFR can compensate when phosphorylation of the other receptor is inhibited. We also demonstrated that TGF-α can induce phosphorylation of c-Met over 6-fold by 8 hours in the absence of HGF, supporting a ligand-independent mechanism. Combined targeting of c-Met and EGFR resulted in an enhanced inhibition of tumor volumes accompanied by a decreased number of proliferating cells and increased apoptosis compared to single agent treatment in vivo.
Together these results suggest that dual blockade of c-Met and EGFR may be a promising clinical therapeutic strategy for treating HNSCC.
Primary malignant melanoma of the duodenum is an unusual oncologic entity. Patients usually present the similar clinical symptoms like other common tumors in this site. And there are no specific radiological features either. The cases with only little melanin pigment or without notable melanin pigment are very misleading, especially in small biopsies or frozen sections. Definite diagnosis depends on both careful histologic examination and the use of proper immunohistochemical stains. Moreover, detailed history and thorough investigation should be made to exclude the preexistence or coexistence of a primary lesion elsewhere. Herein we report the case of a 60-year-old male patient with primary malignant melanoma of the duodenum, which was misdiagnosed as lymphoma or undifferentiated carcinoma in frozen consultation. The patient had achieved disease-free survival for more than 46 months without any evidence of recurrence after surgery.
The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1221457317710561.
Malignant melanoma; Primary; Duodenum; Misdiagnosis
To compare the chemical differences between the medicinal and cultured oyster shells, their chemical profiles were investigated. Using the ultra performance liquid chromatography-electron spraying ionization-mass spectrometry (UPLC-ESI-MS), combined with principal component analysis (PCA) and orthogonal projection to latent structures discriminant analysis (OPLS-DA), the discrimination of the chemical characteristics among the medicinal and cultured oyster shells was established. Moreover, the chemometric analysis revealed some potential key compounds. After a large-scale extraction and isolation, one target key compound was unambiguously identified as caffeine (1) based on extensive spectroscopic data analysis (1D and 2D NMR, MS, and UV) and comparison with literature data.
oyster shell; traditional Chinese medicine; chemical profile; principal component analysis; caffeine
Age-related macular degeneration (AMD) is a multifactorial disease and a prevalent cause of visual impairment in developed countries. Many studies suggest that age-related maculopathy susceptibility 2 (ARMS2) is a second major susceptibility gene for AMD. At present, there is no functional information on this gene. Therefore, the purpose of the present study was to detect the expression of ARMS2 in retinal pigment epithelium (RPE) cells and to investigate the effect of ARMS2 on the phagocytosis function of RPE cells.
Immunofluorescence and reverse transcriptase PCR were used to demonstrate the presence and location of ARMS2 in ARPE-19 (human retinal pigment epithelial cell line, ATCC, catalog No.CRL-2302) cells. siRNA was used to knock down ARMS2 mRNA, and the effects of the knockdown on the phagocytosis function of the ARPE-19 cells were evaluated via Fluorescence Activated Cell Sorting (FACS).
ARMS2 was present in ARPE-19 cells, localized in the cytosol of the perinuclear region. The expression of ARMS2 mRNA (messenger RNA) in ARPE-19 cells transfected with ARMS2-siRNA (small interfering RNA, 0.73±0.08) was decreased compared with normal cells (1.00±0.00) or with cells transfected with scrambled siRNA (0.95±0.13) (P<0.05). After incubation of RPE cells with a latex beads medium for 12, 18, or 24 hours, the fluorescence intensities were 38.04±1.02, 68.92±0.92, and 78.00±0.12 in the ARMS2-siRNA-transfected groups, respectively, and 77.98±5.43, 94.87±0.60, and 98.30±0.11 in the scrambled siRNA-transfected groups, respectively. The fluorescent intensities of the same time points in the two groups were compared using Student's t-test, and the p values were all less than 0.001 at the three different time points.
There is endogenous expression of ARMS2 in ARPE-19 cells. ARMS2 plays a role in the phagocytosis function of RPE cells, and this role may be one of the mechanisms that participates in the development of AMD.
age-related maculopathy susceptibility 2; age-related macular degeneration; retinal pigment epithelium; phagocytosis
Prostate cancer is a major health problem for men in Western societies. Here we report a Prostate Cancer-Specific Targeting Gene-Viro-Therapy (CTGVT-PCa), in which PTEN was inserted into a DD3-controlled oncolytic viral vector (OV) to form Ad.DD3.E1A.E1B(Δ55)-(PTEN) or, briefly, Ad.DD3.D55-PTEN. The woodchuck post-transcriptional element (WPRE) was also introduced at the downstream of the E1A coding sequence, resulting in much higher expression of the E1A gene. DD3 is one of the most prostate cancer-specific genes and has been used as a clinical bio-diagnostic marker. PTEN is frequently inactivated in primary prostate cancers, which is crucial for prostate cancer progression. Therefore, the Ad.DD3.D55-PTEN has prostate cancer specific and potent antitumor effect. The tumor growth rate was almost completely inhibited with the final tumor volume after Ad.DD3.D55-PTEN treatment less than the initial volume at the beginning of Ad.DD3.D55-PTEN treatment, which shows the powerful antitumor effect of Ad.DD3.D55-PTEN on prostate cancer tumor growth. The CTGVT-PCa construct reported here killed all of the prostate cancer cell lines tested, such as DU145, 22RV1 and CL1, but had a reduced or no killing effect on all the non-prostate cancer cell lines tested. The mechanism of action of Ad.DD3.D55-PTEN was due to the induction of apoptosis, as detected by TUNEL assays and flow cytometry. The apoptosis was mediated by mitochondria-dependent and -independent pathways, as determined by caspase assays and mitochondrial membrane potential.
In the title compound, C13H12O2, the dihedral angle between the pyranone and phenyl rings is 57.55 (9)°. In the crystal, the molecules are linked by π–π stacking interactions between the parallel pyranone rings of neighboring molecules with distances of 3.5778 (11) Å and 3.3871 (11) Å between the planes. C—H⋯O interactions also occur.
Structural features of elastic laminae within arteries can provide vital information for both the mechanobiology and the biomechanics of the wall. In this paper, we propose, test, and illustrate a new computer-based scheme for automated analysis of regional distributions of elastic laminae thickness, inter-lamellar distances, and fragmentation (furcation points) from standard histological images. Our scheme eliminates potential artifacts produced by tissue cutting, automatically aligns tissue according to physiologic orientations, and performs cross-sectional measurements along radial directions. A statistical randomized complete block design (RCBD) and F-test were used to assess potential (non)-uniformity of lamellar thicknesses and separations along both radial and circumferential directions. Illustrative results for both normotensive and hypertensive thoracic porcine aorta revealed marked heterogeneity along the radial direction in nearly stress-free samples. Clearly, regional measurements can provide more detailed information about morphologic changes that cannot be gained by globally averaged evaluations alone. We also found that quantifying Furcation Point densities offers new information about potential elastin fragmentation, particularly in response to increased loading due to hypertension.
Vascular Elastin; Automated Histology; Quantitative Pathology; Discrete Radon Transform; Furcation Point Analysis; Randomized Complete Block Design; Hypertension; Marfan Syndrome; Aging
We developed a method to fabricate a periodic array of three-dimensional crescent-like holes (3DCLH) via an inverted hemispherical colloidal lithography. It is found that there exists an extraordinary optical transmission in this non-planar perforated periodic array of 3DCLH when the electric field of the incident light is perpendicular to the cross-line of the crescent-like hole. This extraordinary optical peak is insensitive with the incident angles and sensitive with the angle between the electric field of the incident light to the cross-line of the 3DCLH. Numerical simulation based on finite-difference time-domain method reveals that this peak is caused by an asymmetric localized surface plasmon resonance. This structure might be useful for the optical sensing and optical-integrated circuits.
Surface plasmon polariton; Localized surface plasmon; Extraordinary optical transmission; Colloidal lithography
In previously published studies, oncolytic adenovirus-mediated gene therapy has produced good results in targeting cancer cells. However, safety and efficacy, the two most important aspects in cancer therapy, remain serious challenges. The specific expression or deletion of replication related genes in an adenovirus has been frequently utilized to regulate the cancer cell specificity of a virus. Accordingly, in this study, we deleted 24 bp in E1A (bp924-bp947) and the entirety of E1B, including those genes encoding E1B 55kDa and E1B19kDa. We used the survivin promoter (SP) to control E1A in order to construct a new adenovirus vector named Ad.SP.E1A(Δ24).ΔE1B (briefly Ad.SPDD). HCCS1 (hepatocellular carcinoma suppressor 1) is a novel tumor suppressor gene that is able to specifically induce apoptosis in cancer cells. The expression cassette AFP-HCCS1-WPRE-SV40 was inserted into Ad.SPDD to form Ad.SPDD-HCCS1, enabling us to improve the safety and efficacy of oncolytic-mediated gene therapy for liver cancer.
Ad.SPDD showed a decreased viral yield and less toxicity in normal cells but enhanced toxicity in liver cancer cells, compared with the cancer-specific adenovirus ZD55 (E1B55K deletion). Ad.SPDD-HCCS1 exhibited a potent anti-liver-cancer ability and decreased toxicity in vitro. Ad.SPDD-HCCS1 also showed a measurable capacity to inhibit Huh-7 xenograft tumor growth on nude mice. The underlying mechanism of Ad.SPDD-HCCS1-induced liver cancer cell death was found to be via the mitochondrial apoptosis pathway.
These results demonstrate that Ad.SPDD-HCCS1 was able to elicit reduced toxicity and enhanced efficacy both in vitro and in vivo compared to a previously constructed oncolytic adenovirus. Ad.SPDD-HCCS1 could be a promising candidate for liver cancer therapy.
liver cancer; quadruple regulated adenovirus; HCCS1; mitochondrial apoptosis pathway
Ribonucleotide reductase (RR) is an αnβn (RR1●RR2) complex that maintains balanced dNTP pools by reducing ribonucleoside diphosphates to deoxyribonucleoside diphosphates. RR1 is the catalytic subunit and RR2 houses the free radical required for catalysis. RR is allosterically regulated by its activator ATP and its inhibitor dATP, which regulate RR activity by inducing oligomerization of RR1. Here, we report the first X-ray structures of human RR1 bound to TTP-only, dATP-only, TTP●GDP, TTP●ATP, and TTP●dATP. These structures provide insights into ATP/dATP regulation of RR. At physiological dATP concentrations, RR1 forms inactive hexamers. We determined the first X-ray structure of the RR1●dATP hexamer and used single-particle electron microscopy to visualize the α6●ββ’ 1●dATP holo complex. Site-directed mutagenesis and functional assays confirm that hexamerization is a prerequisite for inhibition by dATP. Our data provide an elegant mechanism for regulating RR activity by dATP-induced oligomerization.
Analysis of the recently solved X-ray crystal structures of yeast ribonucleotide reductase I (RnrI) in complex with effectors and substrates led to the discovery of a conserved water molecule located at the active site that interacted with the 2′ hydroxy of the nucleoside ribose. In this study 2′-(2-hydroxyethyl)-2′-deoxy-adenosine 1 and its 5′-diphosphate 2 were designed and synthesized to see if the conserved water molecule could be displaced by a hydroxylmethylene group, to generate a novel of inhibitors of this enzyme towards the development of potential anti-neoplastic agents. In this paper, we report the synthesis of these two adenosine analogs 1 and 2, and the co-crystal structure of adenosine diphosphate analog 2 bound with RnrI enzyme which displaces the conserved water as hypothesized.
structure-based design; ribonucleotide reductase; nucleoside; nucleotide; crystallography
Detection of interacting risk factors for complex traits is challenging. The choice of an appropriate method, sample size, and allocation of cases and controls are serious concerns. To provide empirical guidelines for planning such studies and data analyses, we investigated the performance of the multifactor dimensionality reduction (MDR) and generalized MDR (GMDR) methods under various experimental scenarios. We developed the mathematical expectation of accuracy and used it as an indicator parameter to perform a gene-gene interaction study. We then examined the statistical power of GMDR and MDR within the plausible range of accuracy (0.50∼0.65) reported in the literature. The GMDR with covariate adjustment had a power of>80% in a case-control design with a sample size of≥2000, with theoretical accuracy ranging from 0.56 to 0.62. However, when the accuracy was<0.56, a sample size of≥4000 was required to have sufficient power. In our simulations, the GMDR outperformed the MDR under all models with accuracy ranging from 0.56∼0.62 for a sample size of 1000–2000. However, the two methods performed similarly when the accuracy was outside this range or the sample was significantly larger. We conclude that with adjustment of a covariate, GMDR performs better than MDR and a sample size of 1000∼2000 is reasonably large for detecting gene-gene interactions in the range of effect size reported by the current literature; whereas larger sample size is required for more subtle interactions with accuracy<0.56.
A qnrVC-like gene, qnrVC4, was found in a novel complex class 1 integron gene cassette array following the ISCR1 element and blaPER-1 in a multidrug-resistant strain of the aquatic bacterium Aeromonas punctata. The deduced QnrVC4 protein sequence shares 45% to 81% amino acid identity with quinolone resistance determinants QnrB6, QnrA1, QnrS1, QnrC, QnrVC1, and QnrVC3. A Ser-83 to Ile amino acid substitution in gyrase A may be mainly responsible for ciprofloxacin resistance in this strain.
AIM: To explore the expression pattern of E2F5 in primary hepatocellular carcinomas (HCCs) and elucidate the roles of E2F5 in hepatocarcinogenesis.
METHODS: E2F5 expression was analyzed in 120 primary HCCs and 29 normal liver tissues by immunohistochemistry analysis. E2F5-small interfering RNA was transfected into HepG2, an E2F5-overexpressed HCC cell line. After E2F5 knockdown, cell growth capacity and migrating potential were examined.
RESULTS: E2F5 was significantly overexpressed in primary HCCs compared with normal liver tissues (P = 0.008). The E2F5-silenced cells showed significantly reduced proliferation (P = 0.004). On the colony formation and soft agar assays, the number of colonies was significantly reduced in E2F5-silenced cells (P = 0.004 and P = 0.009, respectively). E2F5 knockdown resulted in the accumulation of G0/G1 phase cells and a reduction of S phase cells. The number of migrating/invading cells was also reduced after E2F5 knockdown (P = 0.021).
CONCLUSION: To our knowledge, this is the first evidence that E2F5 is commonly overexpressed in primary HCC and that E2F5 knockdown significantly repressed the growth of HCC cells.
E2F5; E2F family; Hepatocellular carcinoma; Oncogene; Small interfering RNA
Silkworm is the basis of sericultural industry and the model organism in insect genetics study. Mapping quantitative trait loci (QTLs) underlying economically important traits of silkworm is of high significance for promoting the silkworm molecular breeding and advancing our knowledge on genetic architecture of the Lepidoptera. Yet, the currently used mapping methods are not well suitable for silkworm, because of ignoring the recombination difference in meiosis between two sexes.
A mixed linear model including QTL main effects, epistatic effects, and QTL × sex interaction effects was proposed for mapping QTLs in an F2 population of silkworm. The number and positions of QTLs were determined by F-test and model selection. The Markov chain Monte Carlo (MCMC) algorithm was employed to estimate and test genetic effects of QTLs and QTL × sex interaction effects. The effectiveness of the model and statistical method was validated by a series of simulations. The results indicate that when markers are distributed sparsely on chromosomes, our method will substantially improve estimation accuracy as compared to the normal chiasmate F2 model. We also found that a sample size of hundreds was sufficiently large to unbiasedly estimate all the four types of epistases (i.e., additive-additive, additive-dominance, dominance-additive, and dominance-dominance) when the paired QTLs reside on different chromosomes in silkworm.
The proposed method could accurately estimate not only the additive, dominance and digenic epistatic effects but also their interaction effects with sex, correcting the potential bias and precision loss in the current QTL mapping practice of silkworm and thus representing an important addition to the arsenal of QTL mapping tools.
The brown planthopper (BPH) Nilaparvata lugens (Stål) is one of the most serious insect pests of rice in Asia. However, little is known about the mechanisms responsible for the development, wing dimorphism and sex difference in this species. Genomic information for BPH is currently unavailable, and, therefore, transcriptome and expression profiling data for this species are needed as an important resource to better understand the biological mechanisms of BPH.
In this study, we performed de novo transcriptome assembly and gene expression analysis using short-read sequencing technology (Illumina) combined with a tag-based digital gene expression (DGE) system. The transcriptome analysis assembles the gene information for different developmental stages, sexes and wing forms of BPH. In addition, we constructed six DGE libraries: eggs, second instar nymphs, fifth instar nymphs, brachypterous female adults, macropterous female adults and macropterous male adults. Illumina sequencing revealed 85,526 unigenes, including 13,102 clusters and 72,424 singletons. Transcriptome sequences larger than 350 bp were subjected to Gene Orthology (GO) and KEGG Orthology (KO) annotations. To analyze the DGE profiling, we mainly compared the gene expression variations between eggs and second instar nymphs; second and fifth instar nymphs; fifth instar nymphs and three types of adults; brachypterous and macropterous female adults as well as macropterous female and male adults. Thousands of genes showed significantly different expression levels based on the various comparisons. And we randomly selected some genes to confirm their altered expression levels by quantitative real-time PCR (qRT-PCR).
The obtained BPH transcriptome and DGE profiling data provide comprehensive gene expression information at the transcriptional level that could facilitate our understanding of the molecular mechanisms from various physiological aspects including development, wing dimorphism and sex difference in BPH.
In the title compound, C16H19NO4, a potent new herbicide, the dihedral angle between the benzene and pyrrolidine rings is 11.09 (8)°. Intramolecular O—H⋯O and C—H⋯O hydrogen bonds are observed.
Neuron-derived neurotrophic factor (NDNF) is evolutionarily well conserved, being present in invertebrate animals such as the nematode, Caenorhabditis elegans, as well as in the fruit fly, Drosophila melanogaster. Multiple cysteines are conserved between species and secondary structure prediction shows that NDNF is mainly composed of beta-strands. In this study, we aimed to investigate the function of NDNF.
NDNF is a glycosylated, disulfide-bonded secretory protein that contains a fibronectin type III domain. NDNF promoted migration and growth and elicited neurite outgrowth of mouse hippocampal neurons in culture. NDNF also protected cultured hippocamal neurons against excitotoxicity and amyloid beta-peptide toxicity. Western blotting showed that NDNF was exclusively expressed in the brain and spinal cord. Immunostaining indicated that NDNF was expressed by neurons and not by astrocytes. Cajal-Retzius cells, cortex neurons, hippocampus neurons, olfactory mitral cells, cerebellar purkinje cells, cerebellar granular cells and spinal neurons were found to be NDNF-positive. NDNF expression was observed in the neurons during development.
The results of this study indicated that NDNF is a novel neurotrophic factor derived from neurons that may be useful in the treatment of neuronal degeneration diseases and nerve injuries.
In the title compound, C18H20N2O3, the dihedral angle between the indole ring system (r.m.s. deviation = 0.018 Å) and the hydroxymethylenepyrrolidine-2,4-dione plane (r.m.s. deviation = 0.036 Å) is 9.87 (7)°. The keto and enol groups are involved in an intramolecular O—H⋯O hydrogen bond. An intramolecular C—H⋯O interaction also occurs. The sec-butyl group is disordered over two orientations corresponding to an approximate 180° rotation about the N—C bond, with occupancies of 0.670 (6) and 0.330 (6). In the crystal, molecules are linked into chains along the c axis by C—H⋯O hydrogen bonds.