Transcriptome profiling of the testis reveals genes involved in spermatogenesis and marker discovery in the oriental fruit fly, Bactrocera dorsalis

The testis is a highly specialized tissue that plays a vital role in ensuring fertility by producing spermatozoa, which are transferred to the female during mating. Spermatogenesis is a complex process, resulting in the production of mature sperm, and involves significant structural and biochemical changes in the seminiferous epithelium of the adult testis. The identification of genes involved in spermatogenesis of Bactrocera dorsalis (Hendel) is critical for a better understanding of its reproductive development. In this study, we constructed a cDNA library of testes from male B. dorsalis adults at different ages, and performed de novo transcriptome sequencing to produce a comprehensive transcript data set, using Illumina sequencing technology. The analysis yielded 52 016 732 clean reads, including a total of 4.65 Gb of nucleotides. These reads were assembled into 47 677 contigs (average 443 bp) and then clustered into 30 516 unigenes (average 756 bp). Based on BLAST hits with known proteins in different databases, 20 921 unigenes were annotated with a cut-off E-value of 10(-5). The transcriptome sequences were further annotated using the Clusters of Orthologous Groups, Gene Orthology and the Kyoto Encyclopedia of Genes and Genomes databases. Functional genes involved in spermatogenesis were analysed, including cell cycle proteins, metalloproteins, actin, and ubiquitin and antihyperthermia proteins. Several testis-specific genes were also identified. The transcripts database will help us to understand the molecular mechanisms underlying spermatogenesis in B. dorsalis. Furthermore, 2913 simple sequence repeats and 151 431 single nucleotide polymorphisms were identified, which will be useful for investigating the genetic diversity of B. dorsalis in the future.

Altered brain activation patterns under different working memory loads in patients with type 2 diabetes

OBJECTIVE

Type 2 diabetes mellitus (T2DM) has important effects on cognition and the risk for Alzheimer disease (AD). Working memory (WM) is a susceptible cognitive domain of mild cognitive impairment and AD. Thus, the identification of brain activation patterns under different WM loads can potentially enhance our understanding of the mechanisms underlying cognitive dysfunction in T2DM.

RESEARCH DESIGN AND METHODS

The current study assessed the effects of T2DM on cognitive performance and explored the related neuronal damage through a visual n-back task and functional magnetic resonance imaging.

RESULTS

We found that patients with T2DM exhibited worse executive and memory abilities than control subjects. Furthermore, the patterns of brain activation changed under different WM loads in the T2DM patients, who exhibited reduced activation in the left inferior frontal gyrus under low loads and reduced activation in the left middle frontal gyrus and superior frontal gyrus (SFG) under high loads. Thus, more regions of diminished activation were seen in the frontal cortex with increasing task difficulty. Furthermore, we found that lower SFG activation was associated with worse cognitive function.

CONCLUSIONS

The findings demonstrate deficient WM in patients with T2DM and the relation between cognitive function and degree of neuronal activity and their relevance to AD risk. Further longitudinal studies are needed to replicate these results and to evaluate the clinical value of brain imaging methods in the prediction of disease progress in these patients.

Deep sequencing of small RNA libraries reveals dynamic expression patterns of microRNAs in multiple developmental stages of Bactrocera dorsalis

In eukaryotes, microRNAs (miRNAs) are small, conserved, noncoding RNAs that have emerged as critical regulators of gene expression. The oriental fruit fly Bactrocera dorsalis is one of the most economically important fruit fly pests in East Asia and the Pacific. Although transcriptome analyses have greatly enriched our knowledge of its structural genes, little is known about post-transcriptional regulation by miRNAs in this dipteran species. In this study, small RNA libraries corresponding to four B. dorsalis developmental stages (eggs, larvae, pupae and adults) were constructed and sequenced. Approximately 30.7 million reads of 18-30 nucleotides were obtained, with 123 known miRNAs and 60 novel miRNAs identified amongst these libraries. More than half of the miRNAs were stage-specific during the four developmental stages. A set of miRNAs was found to be up- or down-regulated during development by comparison of their reads at different developmental stages. Moreover, a small part of miRNAs owned both miR-#-3p and miR-#-5p types, with enormously variable miR-#-3p/miR-#-5p ratios in the same library and amongst different developmental stages for each miRNA. Taking these findings together, the current study has uncovered a number of miRNAs and provided insights into their possible involvement in developmental regulation by expression profiling of miRNAs. Further analyses of the expression and function of these miRNAs could increase our understanding of regulatory networks in this insect and lead to novel approaches for its control.

Genetic variations of ISL1 associated with human congenital heart disease in Chinese Han people

Congenital heart disease (CHD) is the most common birth abnormality, but the etiology of CHD is unknown. ISL1 may play a fundamental role in cardiac morphogenesis, and mutations of this gene could cause CHD. To evaluate whether genetic variations of ISL1 are associated with CHD in Chinese Han people, polymerase chain reaction restriction fragment-length polymorphism and SNaPshot were used to examine 9 polymorphisms of ISL1 in 233 patients with CHD as well as 288 healthy controls. We found that one SNP (rs1017) in ISL1 was significantly associated with simple CHD. Genetic variation of ISL1 was confirmed to be associated with the risk of CHD. ISL1 is related to the atrial septal defect group and the ventricular septal defect group, and the genotypes were associated with the occurrence of CHD in the dominant mode of inheritance. We concluded that rs1017 contributed to the risk of CHD in Chinese Han people, and ISL1 may be involved in the formation and development of the heart.

Ameliorative effects of baicalein on an amyloid-β induced Alzheimer's disease rat model: a proteomics study

BACKGROUND

Alzheimer's disease (AD) is the most common type of age-related dementia. Effective anti-AD drugs against amyloid-β-protein-induced cognitive impairment are still lacking. Baicalein is the main component of Radix Scutellariae and has neuroprotective properties. In this study, we provide further insights into pharmacotherapy mechanisms and potential targets of baicalein in AD.

OBJECTIVE

To investigate the therapeutic effects and mechanism of action of baicalein in an AD rat model.

METHODS

Male rats were intracerebroventricularly injected with amyloid-β(Aβ) 1-40, and baicalein was orally administered. The therapeutic effect was evaluated with the Morris water maze test, and the mechanism of action was studied using a proteomics approach and western blotting.

RESULTS

Baicalein treatment significantly attenuated Aβ1-40-induced abnormalities in cognitive function. Additionally, the expression levels of 24 proteins in the cerebral cortex and hippocampus were significantly influenced by baicalein; approximately 50% of these proteins are related to energy metabolism and neurotransmission, whereas others are related to anti-apoptosis, anti-oxidation, the stress response, protein phosphorylation, the cytoskeleton, phospholipid metabolism and cell signaling. The expression of these proteins was increased, except for the proteins related to the cytoskeleton. The changes in the expression of 2 proteins were confirmed by western blotting.

CONCLUSIONS

Baicalein ameliorates the Aβ1-40-induced dementia in rats and may be a novel and promising drug for the treatment of AD. The therapeutic mechanism may be related to modulation of a number of processes, mainly through the promotion of energy metabolism and neurotransmission, with the additional promotion of anti-apoptosis, anti-oxidation, protein phosphorylation, etc.

Lack of Epstein-Barr virus infection in Chinese myasthenia gravis patients

OBJECTIVE

There are three recent contradictory reports on the incidence of Epstein-Barr virus in the pathogenesis of myasthenia gravis, with all studies carried out in Caucasian patients. The current study evaluated whether Epstein-Barr virus infection had a role in the pathogenesis of myasthenia gravis in a cohort of 30 Chinese patients.

MATERIALS AND METHODS

Serial paraffin sections of thymic hyperplasia obtained from myasthenia gravis patients were analyzed for the presence of Epstein-Barr virus-encoded small RNA -1 and Epstein-Barr virus latent membrane protein 1 by in situ hybridization and immunohistochemistry, respectively. Epstein-Barr virus(+) cervical lymph nodes from lymphoma patients and Epstein-Barr virus(-) thymus specimens obtained during cardiac surgery served as the positive and negative control groups, respectively.

RESULTS

All the 30 myasthenia gravis specimens were negative for both Epstein-Barr virus-encoded small RNA -1 and Epstein-Barr virus latent membrane protein 1 tests. However, we obtained well-characterized membrane and cytoplasmic immunohistochemical and in situ hybridization staining for both Epstein-Barr virus latent membrane protein 1 and Epstein-Barr virus-encoded small RNA -1, respectively, in the positive control samples.

CONCLUSIONS

Our results therefore do not support a role of thymic Epstein-Barr virus infection in myasthenia gravis pathogenesis and calls for an integration of methodological and interpretation issues in detecting Epstein-Barr virus incidence in myasthenia gravis patients.

Slow and stored light by photo-isomerization induced transparency in dye doped chiral nematics

Decelerating and stopping light is fundamental for optical processing, high performance sensor technologies and digital signal treatment, many of these applications relying on the ability of controlling the amplitude and phase of coherent light pulses. In this context, slow-light has been achieved by various methods, as coupling light into resonant media, Brillouin scattering in optical fibers, beam coupling in photorefractive and liquid crystal media or engineered dispersion in photonic crystals. Here, we present a different mechanism for slowing and storing light, which is based on photo-isomerization induced transparency of azo-dye molecules hosted in a chiral liquid crystal structure. Sharp spectral features of the medium absorption/dispersion, and the long population lifetime of the dye metastable state, enable the storage of light pulses with a significant retrieval after times much longer than the medium response time.

Rare case of cerebral MALToma presenting with stroke-like symptoms and seizures

Mucosa-associated lymphoid tissue (MALT) cells are present in gastrointestinal mucosa but rarely found in the central nervous system (CNS). We describe an unusual and rare case of CNS MALT lymphoma in a patient presenting with stroke-like symptoms.

Molecular interaction of PCB153 to human serum albumin: insights from spectroscopic and molecular modeling studies

Polychlorinated biphenyls (PCBs) possessed much potential hazard to environment because of its chemical stability and biological toxicity. Here, we identified the binding mode of a representative compound, PCB153, to human serum albumin (HSA) using fluorescence and molecular dynamics simulation methods. The fluorescence study showed that the intrinsic fluorescence of HSA was quenched by addition of PCB153 through a static quenching mechanism. The thermodynamic analysis proved the binding behavior was mainly governed by hydrophobic force. Furthermore, as evidenced by site marker displacement experiments using two probe compounds, it revealed that PCB153 acted exactly on subdomain IIIA (site II) of HSA. On the other hand, the molecular dynamics studies as well as free energy calculations made another important contribution to understand the conformational changes of HSA and the stability of HSA-PCB153 system. Molecular docking revealed PCB153 can bind in a large hydrophobic activity of subdomain IIIA by the hydrophobic interaction and hydrogen bond interactions between chlorine atoms and residue ASN391. The present work provided reasonable models helping us further understand the transporting, distribution and toxicity effect of PCBs when it spread into human blood serum.

Phase conjugation and slow light in dye-doped chiral nematics

Optical phase conjugation and slow light are obtained in dye-doped chiral nematics via degenerate four-wave mixing. The creation of the light-induced dynamical grating is described and the amplitude of the phase-conjugate wave is shown to follow the changes of the input signal, hence providing efficient distortion correction. Associated to these capabilities, slowing down of light pulses is obtained thanks to the dispersive properties of the wave mixing occurring in the cholesteric liquid crystals, opening the way to applications in interferometry and imaging through highly scattering media.

SP600125, a JNK inhibitor, suppresses growth of JNK-inactive glioblastoma cells through cell-cycle G2/M phase arrest

SP600125 is a well studied inhibitor of c-Jun N-terminal kinase (JNK). Its direct biochemical effects on JNK-inactive tumor cells are usually ignored. In this study, we investigated the effects of SP600125 on JNK-inactive U251 human glioblastoma cells. Our results demonstrate that, 20 microM or more SP600125 can induce significant cell growth inhibition and cell-cycle G2/M phase arrest in U251 cells. Interestingly, we also found that SP600125 can stop the duplicated chromosomes from separating into two cells and the karyokinesis progression. Our study opened up a new perspective for further studies involved in JNK inhibitors or anti-glioma therapy.

Gold nanocluster-conjugated amphiphilic block copolymer for tumor-targeted drug delivery

Two kinds of core-shell structured multifunctional nanocarriers of gold nanoclusters (Au NCs) as core and folate (FA)-conjugated amphiphilic hyperbranched block copolymer as shell based on poly(L-lactide) (PLA) inner arm and FA-conjugated sulfated polysaccharide (GPPS-FA) outer arm (Au NCs-PLA-GPPS-FA) were synthesized for targeted anticancer drug delivery. The structure and properties of Au NCs-PLA-GPPS-FA copolymers were characterized and determined by ¹H NMR spectrum, FT-IR spectra, dynamic light scattering (DLS), fluorescence spectroscopy, and transmission electron microscopic (TEM) analyses. The anticancer drug, camptothecin (CPT) was used as a hydrophobic model anticancer drug. In vitro, two kinds of the nanocarriers presented a relatively rapid release in the first stage (up to 1 h) followed by a sustained release period (up to 15 h), and then reached a plateau at pH 5.3, 7.4, and 9.6. The release results indicated that CPT release from two kinds of the nanocarriers at pH 9.6 was much greater than that at both pH 5.3 and 7.4. The cytotoxicity studies showed that the CPT-loaded nanocarriers provided high anticancer activity against Hela cells. Furthermore, nanocarriers gained specificity to target some cancer cells because of the enhanced cell uptake mediated by FA moiety. The fluorescent images studies showed that the nanocarriers could track at the cellular level for advance therapy. The results indicated that the Au NCs-PLA-GPPS-FA copolymers not only had great potential as tumor-targeted drug delivery carrier, but also had an assistant role in the treatment of cancer.

Core-shell nanocarriers with ZnO quantum dots-conjugated Au nanoparticle for tumor-targeted drug delivery

Core-shell structured multifunctional nanocarriers (NCs) of ZnO quantum dots-conjugated gold nanoparticles (Au NPs) as core and amphiphilic hyperbranched block copolymer as shell were synthesized for targeted anticancer drug delivery. The amphiphilic hyperbranched block copolymer contained poly(l-lactide) (PLA) inner arm and folate (FA)-conjugated a sulfated polysaccharide from Gynostemma pentaphyllum Makino (GPPS-FA) outer arm. The structure and properties of core-shell structured multifunctional nanocarriers were characterized and determined by UV-visible spectra, FT-IR spectra, X-ray diffraction (XRD), fluorescence spectroscopy and TEM analyses. The release results indicated that camptothecin (CPT) release from NCs at pH 7.4 was much greater than that at pH 5.3. The cytotoxicity studies showed that both the blank NCs and the CPT-loaded NCs provided high anticancer activity against Hela cells. Furthermore, nanocarriers gained specificity to target model cancer cells in this study due to the enhanced cell uptake mediated by FA moiety. The results indicated that the NCs not only had great potential as tumor-targeted drug delivery nanocarrier, but also had an assistant role in the treatment of cancer.