Improving toxicity of Bacillus thuringiensis strain contains the cry8Ca gene specific to Anomala corpulenta larvae

The cry8C-type gene designated cry8Ca2, which was cloned and sequenced from a Bacillus thuringiensis isolate HBF-1 in China, consisted of an open reading frame of 3483 bp encoding a protein of 1160 amino-acid residues. Sequence analysis showed that the Cry8Ca2 protoxin of 130.5 kDa had 99.9% sequence homology with the previously reported Cry8Ca1 protein, with one mismatch between the two amino-acid sequences. When the Cry8Ca2 toxin was expressed in a crystal-negative strain of B. thuringiensis (HD-73(-)), elliptical crystals were produced. Cell extracts from this recombinant strain showed insecticidal activity against Anomala corpulenta larva. Mutant cry8Ca2 genes, produced by polymerase chain reaction amplification with Taq DNA polymerase, were used to develop recombinant B. thuringiensis strains. Mutants producing higher levels of insecticidal activity were identified by bioassay. Thirty-five mutants forming crystals were characterized, and two of them showed significantly increased insecticidal activity against A. corpulenta larva. The 50% lethality concentrations (LC(50)) of the two mutants were 0.2334 x 10(8) and 0.2591 x 10(8) colony-forming units g(-1), considerably lower than the LC(50) of the wild-type strain HBF-1 (0.9583 x 10(8) CFU g(-1)) and that of B. thuringiensis serovar japonensis strain Buibui (1.0752 x 10(8) CFU g(-1)).

Biologic effect and immunoisolating behavior of BMP-2 gene-transfected bone marrow-derived mesenchymal stem cells in APA microcapsules

We investigated the encapsulation of BMP-2 gene-modified mesenchymal stem cells (MSCs) in alginate-poly-L-lysine (APA) microcapsules for the persistent delivery of bone morphogenic protein-2 (BMP-2) to induce bone formation. An electrostatic droplet generator was employed to produce APA microcapsules containing encapsulated beta-gal or BMP-2 gene-transfected bone marrow-derived MSCs. We found that X-gal staining was still positive 28 days after encapsulation. Encapsulated BMP-2 gene-transfected cells were capable of constitutive delivery of BMP-2 proteins for at least 30 days. The encapsulated BMP-2 gene-transfected MSCs or the encapsulated non-gene transfer MSCs (control group) were cocultured with the undifferentiated MSCs. The gene products from the encapsulated BMP-2 cells could induce the undifferentiated MSCs to become osteoblasts that had higher alkaline phosphatase (ALP) activity than those in the control group (p<0.05). The APA microcapsules could inhibit the permeation of fluorescein isothiocyanate-conjuncted immunoglobulin G. Mixed lymphocyte reaction also indicates that the APA microcapsules could prevent the encapsulated BMP-2 gene-transfected MSCs from initiating the cellular immune response. These results demonstrated that the nonautologous BMP-2 gene-transfected stem cells are of potential utility for enhancement of bone repair and bone regeneration in vivo.

CD4(+)CD25(+) regulatory T cells contribute to the therapeutic effects of glatiramer acetate in experimental autoimmune encephalomyelitis

CD4(+)CD25(+) regulatory T cells (Tregs) are potent immunosuppressors that are pivotal in the maintenance of self-tolerance. The involvement of Tregs in therapies for immune-mediated diseases has been proposed, but direct supporting evidence is still lacking. While investigating mechanisms underlying the clinical benefits of glatiramer acetate (GA) in an animal model of multiple sclerosis (MS), i.e., experimental autoimmune encephalomyelitis (EAE), we recently demonstrated that GA can protect mice deficient in the Th(2) cytokines IL-4, IL-10 and IL-4/IL-10 from acquiring EAE, suggesting that mechanisms other than Th(2) cells may be responsible for the therapeutic effects of GA. Here we demonstrate that GA treatment boosts the expression of Foxp3 on Tregs during EAE. Furthermore, adoptive transfer of purified Tregs from GA-treated EAE mice is more effective in preventing EAE development than Tregs from untreated EAE controls. Thus, our current data provide evidence that Tregs may be the major contributor to GA's therapeutic action in EAE and, possibly, MS. Further mechanistic studies to reveal the molecular events linking GA with Tregs may optimize GA treatment and lead to the development of new, even more effective therapies that utilize this mechanism of action.

[Construction of T-vectors for the direct, unidirectional cloning and analysis of PCR-amplified promoters]

The amplification and cloning of promoters are regularly employed procedures to study the mechanism of gene regulation. In the present study we developed a method to construct T-vectors used for the direct and unidirectional cloning and analysis of promoters. These so-called T-vectors pEGFP-T and pGL3-T were derived from their parent promoterless vectors pEGFP-1 and pGL3-basic, respectively. To construct the T-vectors, an AhdI recognition site within the Ampr gene in pGL3-basic was silent mutated using overlap extension PCR. Then, a specially designed AhdI cassette was cloned into the respective parent vectors. The procedures of the T-vector construction involved a strategy to minimize the background of nonrecombinant transformants and to eliminate reverse orientation of the PCR products into the T-vectors. The cloning efficiencies of the two T-vectors were both above 85% when tested with a PCR product amplified from a sequence that was pre-confirmed to be able to initiate transcription, and moreover, the constructs harbored the inserts in a desired orientation at a >90% rate. In transient transfection assays, we demonstrated these T-vectors are functional. Thus, the present study provides an easy method to construct a series of T-vectors used for promoter characterization.

Microfluidic system integration in sample preparation chip-sets - a summary

An increasing complexity of microfluidic chips and systems used for biochemical assay applications calls for the development of new strategies towards their functionality integration in order to achieve optimum assay performance. Approaches to an integration of microfluidic chips into diagnostic fluidic systems are reviewed with the emphasis on the selection of assay application, integration scheme, interfacing, and fabrication platform. In particular, we discuss a system containing polymer microfluidic chip-sets capable of cell pre-concentration from a complex sample matrix using immunomagnetic separations.

Prevalence of asymptomatic intracranial atherosclerosis in high-risk patients

We used transcranial Doppler to screen 3,057 patients who had at least one vascular risk factor of hypertension, diabetes, or hyperlipidemia and found 385 (12.6%) had middle cerebral artery stenosis. Elderly, hypertension, diabetes, and hyperlipidemia were associated factors. The prevalence escalated quadratically with increasing number of associated factors: from 7.2% for one, to 29.6% for four associated factors. Asymptomatic middle cerebral artery stenosis is common in patients with vascular risk factors.

Crosstalk between the connecting tubule and the afferent arteriole regulates renal microcirculation

The renal afferent arterioles (Af-Arts) account for most of the renal vascular resistance, which is controlled similar to other arterioles and by tubuloglomerular feedback (TGF). The latter signal is generated by sensing sodium chloride concentrations in the macula densa; this in turn results in a signal which acts through the extraglomerular mesangium leading to constriction of the Af-Art. In the outer renal cortex, the connecting tubule (CNT) returns to the glomerular hilus and contacts the Af-Art suggesting that crosstalk may exist here as well. To investigate this, we simultaneously perfused a microdissected Af-Art and adherent CNT. Increasing the sodium chloride concentration perfusing the CNT significantly dilated preconstricted Af-Arts. We called this crosstalk 'connecting tubule glomerular feedback' (CTGF) to differentiate it from TGF. We tested whether entry of Na(+) and/or CI(-) into the CNT is required to induce CTGF by replacing Na(+) with choline(+). Increasing choline chloride concentration did not dilate the Af-Art. To test whether epithelial Na channels (ENaCs) mediate CTGF, we blocked ENaC with amiloride and found that the dilatation induced by CTGF was completely blocked. Inhibiting sodium chloride cotransporters with hydrochlorothiazide failed to prevent Af-Art dilatation. Finally, we tested whether nitric oxide released by the CNT mediates CTGF by the addition of a non-selective nitric oxide synthase inhibitor to the CNT. This potentiated CTGF rather than blocking it. We suggest that crosstalk exists between CNTs and attached Af-Arts, which is initiated by sodium reabsorption through amiloride-sensitive channels and this can contribute to the regulation of renal blood flow and glomerular filtration.

Measurement of branching fractions and mass spectra of B-->Kpipigamma

We present a measurement of the partial branching fractions and mass spectra of the exclusive radiative penguin processes B-->Kpipigamma in the range m(Kpipi)<1.8 GeV/c(2). We reconstruct four final states: K(+)pi(-)pi(+)gamma, K(+)pi(-)pi(0)gamma, K(S)(0)pi(-)pi(+)gamma, and K(S)(0)pi(+)pi(0)gamma, where K(S)(0)-->pi(+)pi(-). Using 232 x 10(6) e(+)e(-)-->BB events recorded by the BABAR experiment at the SLAC PEP-II asymmetric-energy storage ring, we measure the branching fractions B(B(+)-->K(+)pi(-)pi(+)gamma)=[2.95+/-0.13(stat)+/-0.20(syst)] x 10(-5), B(B(0)-->K(+)pi(-)pi(0)gamma)=[4.07+/-0.22(stat)+/-0.31(syst)] x 10(-5), B(B(0)-->K(0)pi(+)pi(-)gamma)=[1.85+/-0.21(stat)+/-0.12(syst)] x 10(-5), and B(B(+)-->K(0)pi(+)pi(0)gamma)=[4.56+/-0.42(stat)+/-0.31(syst)] x 10(-5).

Induction and selective accumulation of mutant ubiquitin in CA1 pyramidal neurons after transient global ischemia

Accumulation of mutant ubiquitin-B (UBB(+1)) in neurons is considered the hallmark of proteasomal dysfunction in neurodegenerative disorders, however no such evidence in ischemic brain has been reported. We investigated the contribution of UBB(+1) in delayed neuronal death after transient global ischemia. Transient global ischemia was achieved by occlusion of bilateral common carotid arteries for 5 min and reperfusion in male Mongolian gerbils (n=6 per each time point). In the CA1 region, UBB(+1) immunoreactivity appeared in the cytoplasm of pyramidal cells at 30 min post-ischemia, and the density of these neurons increased at day 2 (P<0.001) and further increased at day 4 post-ischemia. Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL)-positive (apoptotic) cells appeared selectively in the CA1 region at day 3 and their density increased further at day 4 post-ischemia (P<0.001). In contrast, UBB(+1) immunoreactivity was only transiently detected from 30 min to 1 day post-ischemia in CA3, dentate gyrus, and frontal cortex, but disappeared at day 2 post-ischemia. No TUNEL-positive cells were observed in these three regions. UBB(+1) mRNA was detected by reverse transcription-polymerase chain reaction in every region of the hippocampus and frontal cortex of ischemic gerbils and even in the non-ischemic control animals, and its expression level was independent of brain region and time after ischemia. Our results indicate induction and selective accumulation of UBB(+1) protein in dying neurons of the CA1 region and suggest that UBB(+1) expression may be induced by proteasomal dysfunction after transient global ischemia.

Possible mechanism of efferent arteriole (Ef-Art) tubuloglomerular feedback

Adenosine triphosphate (ATP) is liberated from macula densa cells in response to increased tubular NaCl delivery. However, it is not known whether ATP from the macula densa is broken down to adenosine, or whether this adenosine mediates efferent arteriole (Ef-Art) tubuloglomerular feedback (TGF). We hypothesized that increased macula densa Ca(2+), release of ATP and degradation of ATP to adenosine are necessary for Ef-Art TGF. Rabbit Ef-Arts and adherent tubular segments (with the macula densa) were simultaneously microperfused in vitro while changing the NaCl concentration at the macula densa. The Ef-Art was perfused orthograde through the end of the afferent arteriole (Af-Art). In Ef-Arts preconstricted with norepinephrine (NE), increasing NaCl concentration from 10 to 80 mM at the macula densa dilated Ef-Arts from 7.5+/-0.7 to 11.1+/-0.3 microm. Buffering increases in macula densa Ca(2+) with the cell-permeant Ca(2+) chelator BAPTA-AM diminished Ef-Art TGF from 3.1+/-0.3 to 0.1+/-0.2 microm. Blocking adenosine formation by adding alpha-beta-methyleneadenosine 5'-diphosphate (MADP) blocked Ef-Art TGF from 2.9+/-0.5 to 0.1+/-0.2 microm. Increasing luminal NaCl at the macula densa from 10 to 45 mM caused a moderate Ef-Art TGF response, 1.3+/-0.1 microm. It was potentiated to 4.0+/-0.3 microm by adding hexokinase, which enhances conversion of ATP into adenosine. Our data show that in vitro changes in macula densa Ca(2+) and ATP release are necessary for Ef-Art TGF. ATP is broken down to form adenosine, which mediates signal transmission of Ef-Art TGF.

Gadd45a regulates β-catenin distribution and maintains cell–cell adhesion/contact

Gadd45a, a growth arrest and DNA-damage gene, plays important roles in the control of cell cycle checkpoints, DNA repair and apoptosis. We show here that Gadd45a is involved in the control of cell contact inhibition and cell-cell adhesion. Gadd45a can serve as an adapter to enhance the interaction between beta-catenin and Caveolin-1, and in turn induces beta-catenin translocation to cell membrane for maintaining cell-cell adhesion/contact inhibition. This is coupled with reduction of beta-catenin in cytoplasm and nucleus following Gadd45a induction, which is reflected by the downregulation of cyclin D1, one of the beta-catenin targeted genes. Additionally, Gadd45a facilitates ultraviolet radiation-induced degradation of cytoplasmic and nuclear beta-catenin in a p53-dependent manner via activation of p38 kinase. These findings define a novel link that connects Gadd45a to cell-cell adhesion and cell contact inhibition, which might contribute to the role of Gadd45a in inhibiting tumorigenesis.

Measurement of the pseudoscalar decay constant fDs using charm-tagged events in e+e- collisions at square root s=10.58 GeV

Using 230.2 fb-1 of e+e- annihilation data collected with the BABAR detector at and near the peak of the Upsilon(4S) resonance, 489+/-55 events containing the pure leptonic decay Ds+-->micro;+numicro have been isolated in charm-tagged events. The ratio of partial widths Gamma(D+-->micro+numicro)/Gamma(Ds+-->phipi+) is measured to be 0.143+/-0.018+/-0.006 allowing a determination of the pseudoscalar decay constant fDs=(283+/-17+/-7+/-14) MeV. The errors are statistical, systematic, and from the Ds+-->phipi+ branching ratio, respectively.

Observation of decays B0-->Ds(*)+ pi- and B0-->Ds(*)- K+

We report the observation of decays B{0}-->D{s}{(*)+}pi- and B{0}-->D{s}{(*)-}K+ in a sample of 230 x 10(6) Upsilon(4S)-->BB[over] events recorded with the BABAR detector at the SLAC PEP-II asymmetric-energy e+ e- storage ring. We measure the branching fractions B(B{0}-->D{s}{+}pi-)=(1.3+/-0.3(stat)+/-0.2(syst))x10(-5), B(B{0}-->D{s}{-} K+)=(2.5+/-0.4(stat)+/-0.4(syst))x10(-5), B(B{0}-->D{s}{*+}pi-)=(2.8+/-0.6(stat)+/-0.5(syst))x10(-5), and B(B{0}-->D{s}{*-}K+)=(2.0+/-0.5(stat)+/-0.4(syst))x10(-5). The significances of the measurements to differ from zero are 5, 9, 6, and 5 standard deviations, respectively. This is the first observation of B{0}-->D{s}{+}pi-, B{0}-->D{s}{*+}pi-, and B{0}-->D{s}{*-}K+ decays.

Observation of a Charmed Baryon Decaying to D;{0}p at a Mass Near 2.94 GeV/c;{2}

A search for charmed baryons decaying to D(0)p reveals two states: the Lambdac(2880)+ baryon and a previously unobserved state at a mass of [2939.8+/-1.3(stat)+/-1.0(syst)] MeV/c2 and with an intrinsic width of [17.5+/-5.2(stat)+/-5.9(syst)] MeV. Consistent and significant signals are observed for the K(-)pi(+) and K(-)pi(+)pi(-)pi(+) decay modes of the D0 in 287 fb(-1) annihilation data recorded by the BABAR detector at a center-of-mass energy of 10.58 GeV. There is no evidence in the D+p spectrum of doubly charged partners. The mass and intrinsic width of the Lambdac(2880)+ baryon and relative yield of the two baryons are also measured.

Sorption of selected endocrine disrupting chemicals to different aquatic colloids

The sorption of seven endocrine disrupting chemicals (EDCs) to aquatic colloids was determined by cross-flow ultrafiltration (CFUF) followed by gas chromatography-mass spectrometry (GC-MS). Results show that the colloidal organic carbon normalized sorption coefficient (Kcoc) of EDCs to different aquatic colloids varies by a factor of 6-12 because such colloids are of different origin. Through characterization of colloidal samples, a significant relationship was established between Kcoc values and the molar extinction coefficient of colloids at 280 nm, whereas no other colloidal properties such as elemental ratios were correlated with Kcoc values. The results are consistent with other reports of the importance of the quality of sorbents such as their aromatic carbon content in sorbing various organic pollutants. The presence of a surfactant was found to increase Kcoc values for estrone (El) and 17alpha-ethynylestradiol (EE2). The method was subsequently applied for determining EDC concentrations in field samples, where both conventional and truly dissolved EDCs showed higher concentrations close to sewage outfalls than either upstream or downstream, confirming the sourceconcentration relationship. In addition, the truly dissolved EDC concentrations were lower than the conventional dissolved concentrations, confirming that there were interactions between aquatic colloids and EDCs. It is estimated that between 10 and 29% of EDCs are associated with aquatic colloids. As colloids are highly abundant in rivers and ocean, they will therefore play a significant role in the environmental behavior and fate of EDCs.

Inhibition of expression of rna polymerase with small interfering RNAs targeting a conserved motif in the respective viral genes in viruses of the family Flaviviridae

The RNA-dependent RNA polymerase (RdRp) in viruses of the family Flaviviridae plays an important role in the viral replication process and in the forming of a replicase complex. We used small interfering RNAs (siRNAs) corresponding to the highly conservative Motif V of RdRp gene of different viruses to examine their role in modulating the expression of RdRp. Evaluation of the expression of RdRps was performed by the fluorescence, flow cytometry, Western blotting, and real-time PCR. We found that Classical swine fever virus (CSFV) siRNA could completely block the transcription and expression of RdRp. Additionally, Hepatitis C virus (HCV) siRNA could cause effective inhibition of RdRp, whereas Japanese encephalitis virus siRNA did not show significant repression of corresponding RdRp. These results demonstrated that siRNAs inhibited the expression of tested RdRps at the transcription level or at the posttranscriptional processing to a different extent.

Stimulative activity of Drynaria fortunei (Kunze) J. Sm. extracts and two of its flavonoids on the proliferation of osteoblastic like cells

The osteoblastic activity of extracts of Drynaria fortunei (Kunze) J. Sm. rhizome was assayed in the UMR106 cell line cultured in vitro. An ethanol extract and its fractions were added to the cell culture at different concentrations. Osteoblastic proliferation stimulating activity was determined using the MTT method. The ethanol extract, and its ethyl acetate and n-butanol fractions exhibited stimulating activity. Two active constituents were isolated from n-butanol fraction by bioassay-directed isolation, and identified as naringin and neoeriocitrin. The latter is reported for the first time from this herbal medicine.