The technology of large-scale pharmaceutical plasmid purification by cetyltrimethylammonium bromide and Tritonx-114

Many methods for plasmid purification have been developed, and the whole process must be designed to remove the host RNA, protein, genomic DNA and endotoxin. Currently, plasmid is mostly purified by time-consuming chromatographies. As an alternative, a new plasmid purification technology with cetyltrimethylammonium bromide (CTAB) is described. After lysis with alkali, the CTAB was directly titrated into the supernatant for plasmid precipitation, then the coprecipitated pellets were dealt with 3 M KAc and TritonX-114. Quality detection showed that the purified plasmids were free from the contamination of host RNA. In 1 mg purified plasmid, the bacterial genomic DNA, host endotoxin and protein were less than 10 g/ mg, 50 EU/ mg and 10 g/mg, respectively. The ratio of OD260/OD280 was between 1.75 - 1.85, more than 90% of the prepared plasmid presented in the supercoiled form. Further test demonstrated that the pcDNAlacZ purified with CTAB and authoritative endotoxin-free plasmid Kit had the similar transfection efficiency in vivo and in vitro. CTAB can be used for plasmid purification; the main advantages of the DNAs purified with CTAB include the avoidance of animal-derived enzymes, toxic substance like chloroform and phenol. More attractive is that the whole process has the predominance of low cost

Ultraviolet Lasing Characteristics of ZnS Microbelt Lasers

published_or_final_versio

Lasing characteristics of random cylindrical microcavity lasers

Author name used in this publication: H. ZhuVersion of RecordPublishe

Lumbar spinal stenosis: an update on the epidemiology, diagnosis and treatment

Lumbar spinal stenosis (LSS) is a common spinal disorder in the older population, and the clinical syndrome consisting of pain in the buttock or lower extremity, with or without low back pain and corresponding imaging findings of narrowing of spaces around neural and vascular elements in the lumbar spine. The diagnosis depends on history, symptoms, physical examination, radiographies. Varieties of non-operative and operative options are available for LSS patients. In this article, an update on the epidemiology, diagnosis and treatment of LSS was reviewed.published_or_final_versio

The secreted triose phosphate isomerase of Brugia malayi is required to sustain microfilaria production in vivo

Human lymphatic filariasis is a major tropical disease transmitted through mosquito vectors which take up microfilarial larvae from the blood of infected subjects. Microfilariae are produced by long-lived adult parasites, which also release a suite of excretory-secretory products that have recently been subject to in-depth proteomic analysis. Surprisingly, the most abundant secreted protein of adult Brugia malayi is triose phosphate isomerase (TPI), a glycolytic enzyme usually associated with the cytosol. We now show that while TPI is a prominent target of the antibody response to infection, there is little antibody-mediated inhibition of catalytic activity by polyclonal sera. We generated a panel of twenty-three anti-TPI monoclonal antibodies and found only two were able to block TPI enzymatic activity. Immunisation of jirds with B. malayi TPI, or mice with the homologous protein from the rodent filaria Litomosoides sigmodontis, failed to induce neutralising antibodies or protective immunity. In contrast, passive transfer of neutralising monoclonal antibody to mice prior to implantation with adult B. malayi resulted in 60–70% reductions in microfilarial levels in vivo and both oocyte and microfilarial production by individual adult females. The loss of fecundity was accompanied by reduced IFNγ expression by CD4+ T cells and a higher proportion of macrophages at the site of infection. Thus, enzymatically active TPI plays an important role in the transmission cycle of B. malayi filarial parasites and is identified as a potential target for immunological and pharmacological intervention against filarial infections

Regulation of mammary gland branching morphogenesis by the extracellular matrix and its remodeling enzymes.

A considerable body of research indicates that mammary gland branching morphogenesis is dependent, in part, on the extracellular matrix (ECM), ECM-receptors, such as integrins and other ECM receptors, and ECM-degrading enzymes, including matrix metalloproteinases (MMPs) and their inhibitors, tissue inhibitors of metalloproteinases (TIMPs). There is some evidence that these ECM cues affect one or more of the following processes: cell survival, polarity, proliferation, differentiation, adhesion, and migration. Both three-dimensional culture models and genetic manipulations of the mouse mammary gland have been used to study the signaling pathways that affect these processes. However, the precise mechanisms of ECM-directed mammary morphogenesis are not well understood. Mammary morphogenesis involves epithelial 'invasion' of adipose tissue, a process akin to invasion by breast cancer cells, although the former is a highly regulated developmental process. How these morphogenic pathways are integrated in the normal gland and how they become dysregulated and subverted in the progression of breast cancer also remain largely unanswered questions

Excitations of incoherent spin-waves due to spin-transfer torque

As predicted by Slonczewski and Berger, the possibility of exciting microwave oscillations in a nanomagnet by a spin-polarized current has been recently demonstrated. This observation opens very important perspectives of applications in RF components. However, some unresolved inconsistencies are found when interpreting the magnetization dynamics results within the coherent spin-torque model (CSM). In some cases, the telegraph noise caused by spin-currents could not be described quantitatively by the CSM. This led to controversies about the need of an effective magnetic temperature model (ETM). Here we interpret the experimental results of Kiselev et al. [Nature 425, 380 (2003)] using micromagnetic simulations. We point out the key role played by incoherent spin-waves excitation due to spin-transfer effects. The incoherence is caused by the spatial inhomogeneities of the local fields, generating a distribution of local precession frequencies. It results in telegraph noise at zero temperature associated with transitions between attraction wells in phase space.Comment: Nature Materials advance online publication, 7 November 200

SGNP: An Essential Stress Granule/Nucleolar Protein Potentially Involved in 5.8s rRNA Processing/Transport

Background: Stress Granules (SG) are sites of accumulation of stalled initiation complexes that are induced following a variety of cellular insults. In a genetic screen for factors involved in protecting human myoblasts from acute oxidative stress, we identified a gene encoding a protein we designate SGNP (Stress Granule and Nucleolar Protein). Methodology/Principal Findings: A gene-trap insertional mutagenesis screen produced one insertion that conferred resistance to sodium arsenite. RT-PCR/39 RACE was used to identify the endogenous gene expressed as a GFP-fusion transcript. SGNP is localized in both the cytoplasm and nucleolus and defines a non-nucleolar compartment containing 5.8S rRNA, a component of the 60S ribosomal subunit. Under oxidative stress, SGNP nucleolar localization decreases and it rapidly co-localizes with stress granules. The decrease in nucleolar SGNP following oxidative stress was accompanied by a large increase in nucleolar 5.8S rRNA. Knockdown of SGNP with shRNA increased global mRNA translation but induced growth arrest and cell death. Conclusions: These results suggest that SGNP is an essential gene that may be involved in ribosomal biogenesis and translational control in response to oxidative stress

Sequence and Phylogenetic Analysis of SSU rRNA Gene of Five Microsporidia

The complete small subunit rRNA (SSU rRNA) gene sequences of five microsporidia including Nosemaheliothidis, and four novel microsporidia isolated from Pieris rapae, Phyllobrotica armta, Hemerophila atrilineata, and Bombyx mori, respectively, were obtained by PCR amplification, cloning, and sequencing. Two phylogenetic trees based on SSU rRNA sequences had been constructed by using Neighbor-Joining of Phylip software and UPGMA of MEGA4.0 software. The taxonomic status of four novel microsporidia was determined by analysis of phylogenetic relationship, length, G+C content, identity, and divergence of the SSU rRNA sequences. The results showed that the microsporidia isolated from Pieris rapae, Phyllobrotica armta, and Hemerophila atrilineata have close phylogenetic relationship with the Nosema, while another microsporidium isolated from Bombyx mori is closely related to the Endoreticulatus. So, we temporarily classify three novel species of microsporidia to genus Nosema, as Nosema sp. PR, Nosema sp. PA, Nosema sp. HA. Another is temporarily classified into genus Endoreticulatus, as Endoreticulatus sp. Zhenjiang. The result indicated as well that it is feasible and valuable to elucidate phylogenetic relationships and taxonomic status of microsporidian species by analyzing information from SSU rRNA sequences of microsporidia