Reversing endogenous alloreactive B cell GC responses with anti-CD154 or CTLA-4Ig

Alloantibodies mediate acute antibody-mediated rejection as well as chronic allograft rejection in clinical transplantation. To better understand the cellular dynamics driving antibody production, we focused on the activation and differentiation of alloreactive B cells in the draining lymph nodes and spleen following sensitization to allogeneic cells or hearts. We used a modified staining approach with a single MHC Class I tetramer (K(d)) bound to two different fluorochromes to discriminate between the Class I-binding and fluorochrome-streptavidin-binding B cells with a high degree of specificity and binding efficiency. By Day 7-8 postsensitization, there was a 1.5- to 3.2-fold increase in the total numbers of K(d) -binding B cells. Within this K(d) -binding B cell population, approximately half were IgD(low) , MHC Class II(high) and CD86(+), 30-45% expressed a germinal center (Fas(+) GL7(+)) phenotype and 3-12% were IRF4(hi) plasma cells. Remarkably, blockade with anti-CD40 or CTLA-4Ig, starting on Day 7 postimmunization for 1 or 4 weeks, completely dissolved established GCs and halted further development of the alloantibody response. Thus MHC Class I tetramers can specifically track the in vivo fate of endogenous, Class I-specific B cells and was used to demonstrate the ability of delayed treatment with anti-CD154 or CTLA-4Ig to halt established allo-B cell responses.

Measurement of direct CP violation parameters in B± → J/ψK± and B± → J/ψπ± decays with 10.4 fb-1 of Tevatron data

We present a measurement of the direct CP-violating charge asymmetry in B(±) mesons decaying to J/ψK(±) and J/ψπ(±) where J/ψ decays to μ(+) μ(-), using the full run II data set of 10.4 fb(-1) of proton-antiproton collisions collected using the D0 detector at the Fermilab Tevatron Collider. A difference in the yield of B(-) and B(+) mesons in these decays is found by fitting to the difference between their reconstructed invariant mass distributions resulting in asymmetries of A(J/ψK) = [0.59 ± 0.37]%, which is the most precise measurement to date, and A(J/ψπ) = [-4.2 ± 4.5]%. Both measurements are consistent with standard model predictions.

Web-based distance learning for nurse education: a systematic review

BACKGROUND

Web-based distance learning is considered a promising approach to replace or supplement conventional nursing instruction. However, no systematic review has been seen to explore the effect of web-based distance education in nursing.

AIM

To examine the efficacy of the web-based distance education for nursing students and employed nurses.

METHODS

A systematic review of randomized controlled studies was undertaken. Multiple search strategies were performed in PubMed and Embase until July 2012. Two reviewers independently selected trials, conducted quality critical appraisal, and extracted the data from the included studies.

RESULTS

Nine randomized controlled trials met inclusion criteria, among which five studies were rated as A quality level, and the other four studies as B quality level. The results showed that web-based distance learning has produced equivalent or better effects in knowledge acquisition. For nursing skill performance, four studies revealed a positive role for the new teaching mode, and one study showed a negative viewpoint. This review also demonstrated that participants generally accepted web-based education with high satisfaction rates. Two studies reported a more positive trend for self-efficacy in performing nursing skills in the experiment group compared with control group. Some negative feedbacks were also expressed.

CONCLUSION

Web-based education has encouraging effects in improving both participants' knowledge and skills performance, and in enhancing self-efficacy in performing nursing skills, with a high satisfaction rate expressed by participants. More rigorous experimental studies are advocated.

A sero-epidemiological survey of Chinese Babesia motasi for small ruminants in China

Babesia motasi BQ1 (Lintan) was first isolated from Haemaphysalis qinghaiensis collected in Gannan Tibet Autonomous Region, Gansu province in April 2000. In this study, a total of 3,204 serum samples from small ruminants in 22 provinces located in different districts of China were tested for antibodies against merozoite antigens from cultured B. motasi BQ1 (Lintan) by enzyme-linked immunosorbent assay. This method can survey the prevalence of low-pathogenic Chinese B. motasi. The results of this survey indicated that the average positive rate was 43.5 %, and the positive rates of investigated provinces were significantly different from 6.1 to 91.0 %, and the infections had been found in all provinces investigated. Our data provide large important information regarding the current sero-prevalence of B. motasi in China.

Measurement of the semileptonic charge asymmetry using B(s)(0) → D(s)μX decays

We present a measurement of the time-integrated flavor-specific semileptonic charge asymmetry in the decays of B(s)(0) mesons that have undergone flavor mixing, a(sl)(s), using B(s)(0)(B(s)(0)) → D(s)(-/+) μ(±) X decays, with D(s)(-/+) → [symbol: see text]π(-/+) and [symbol: see text]→ K(+) K(-), using 10.4 fb(-1) of proton-antiproton collisions collected by the D0 detector during Run II at the Fermilab Tevatron Collider. A fit to the difference between the time-integrated D(s)(-) and D(s)(+) mass distributions of the B(s)(0) and B(s)(0) candidates yields the flavor-specific asymmetry a(sl)(s) = [-1.12 ± 0.74(stat) ± 0.17(syst)]%, which is the most precise measurement and in agreement with the standard model prediction.

Adenovirus-mediated delivery of soluble ST2 attenuates ovalbumin-induced allergic asthma in mice

Allergic asthma is associated with excessive T helper type 2 (Th2) cells activation and airway hyperreactivity (AHR), implicated in the context of significant morbidity and mortality. Soluble ST2, a member of the interleukin (IL)-1 receptor family, has been shown to play a critical role in modulation of inflammatory disorders, yet the function of soluble ST2 in allergic inflammation remains unclear. In this study, we examined the possibility of regulating ovalbumin (OVA)-challenged airway inflammation by recombinant adenovirus-mediated sST2-Fc (Ad-sST2-Fc) gene transfer. Single intranasal administration of Ad-sST2-Fc before allergen challenge in OVA-immunized mice profoundly reduced serum immunoglobulin (Ig)E secretion, eosinophil infiltration and concentrations of IL-4, IL-5 and IL-13 in bronchoalveolar lavage fluid compared with administration of a control Ad vector. Histopathological examination of the lungs revealed that sST2-Fc over-expression markedly suppressed allergen-induced peribronchial inflammation and disruption of the alveolar architecture. Moreover, the beneficial effect of sST2-Fc in allergic lung inflammation is related to blocking the IL-33/ST2L signalling. Taken together, these results suggested that administration of Ad-sST2-Fc gene transfer may have therapeutic potential for the immunomodulatory treatment of OVA-mediated allergic pulmonary diseases.

Nanocrystalline nickel ferrite particles synthesized by non-hydrolytic sol-gel method and their composite with biodegradable polymer

Targeted drug delivery has been one of the most important biomedical applications for magnetic particles. Such applications require magnetic particles to have functionalized surfaces/surface coatings that facilitate their incorporation into a polymer matrix to produce a polymer composite. In this paper, nanocrystalline nickel ferrite particles with an oleic acid surface coating were synthesized using a non-hydrolytic sol-gel method and incorporated into a biodegradable polymer matrix, poly(D,L-lactide) PLA prepared using a double emulsion method. As-synthesized nickel ferrite particles had a multi-crystalline structure with chemically adsorbed oleic acid on their surface. After forming the PLA composite, nickel ferrite particles were encapsulated in PLA microspheres. At low nickel ferrite concentrations, composites showed very similar surface charges to that of PLA. The composites were magnetically responsive and increasing the nickel ferrite concentration was found to increase magnetization of the composite.

[Prediction of ipsilateral mediastinal lymph node metastasis (N2 disease) in patients with lung cancer]

BACKGROUND

To determine the relation between the clinical pathophysiological characteristics and mediastinal lymph node metastasis (N2 disease) in patients with non-small cell lung cancer(NSCLC).

METHODS

A retrospective study was carried out. Between January, 1996, and October, 1999, 378 patients with NSCLC underwent mediastinal lymph nodes dissection, and 105 of them were proved to be N2 disease through pathological examination. A clinical lymph node staging (c-N) was determined on the basis of findings of preoperative CT scan in each patient: mediastinal or hilar lymph nodes 1.0cm or larger in the shortest axis were diagnosed as metastasis (c-N1-2). Univariate and multivariate analysis were performed to determine the relationship between clinical predictors and pathologically proven N2 disease.

RESULTS

Among all of the 378 cases, N2 disease accounted for 27.8%(105/378). c-N2 disease, adenocarcinoma and c-T3 tumor were the significant clinical predictors of pathological N2 disease on the basis of multivariate analysis (P<0.001). Among 316 patients with c-N0-1 disease, N2 disease accounted for 23.4%(74/316). Adenocarcinoma and c-T2-3 tumor were significant clinical predictors of pathologic N2 disease according to multivariate analysis procedure (P<0.05). When these predictors were combined, more than 50% of adenocarcinoma with c-T3 tumor and about 40% of adenocarcinoma with c-T2 tumor had N2 disease (P<0.01).

CONCLUSIONS

In the patients with adenocarcinoma and c-T2 or c-T3 tumor, probability of pathological N2 disease should be considered.

Search for the standard model Higgs boson in associated WH production in 9.7 fb(-1) of pp collisions with the D0 detector

We present a search for the standard model Higgs boson in final states with a charged lepton (electron or muon), missing transverse energy, and two or three jets, at least one of which is identified as a b-quark jet. The search is primarily sensitive to WH→ℓνbb production and uses data corresponding to 9.7 fb(-1) of integrated luminosity collected with the D0 detector at the Fermilab Tevatron pp Collider at √s = 1.96 TeV. We observe agreement between the data and the expected background. For a Higgs boson mass of 125 GeV, we set a 95% C.L. upper limit on the production of a standard model Higgs boson of 5.2 × σ(SM), where σ(SM) is the standard model Higgs boson production cross section, while the expected limit is 4.7 × σ(SM).

Combined search for the standard model Higgs boson decaying to bb using the D0 run II data set

We present the results of the combination of searches for the standard model Higgs boson produced in association with a W or Z boson and decaying into bb using the data sample collected with the D0 detector in pp collisions at √s = 1.96 TeV at the Fermilab Tevatron Collider. We derive 95% C.L. upper limits on the Higgs boson cross section relative to the standard model prediction in the mass range 100 GeV ≤ M(H) ≤ 150 GeV, and we exclude Higgs bosons with masses smaller than 102 GeV at the 95% C.L. In the mass range 120 GeV ≤ M(H) ≤145 GeV, the data exhibit an excess above the background prediction with a global significance of 1.5 standard deviations, consistent with the expectation in the presence of a standard model Higgs boson.

Search for the standard model Higgs boson in ZH→ℓ(+)ℓ(-)bb production with the D0 detector in 9.7 fb(-1) of pp collisions at √s = 1.96 TeV

We present a search for the standard model (SM) Higgs boson produced in association with a Z boson in 9.7 fb(-1) of pp collisions collected with the D0 detector at the Fermilab Tevatron Collider at √s = 1.96 TeV. Selected events contain one reconstructed Z→e(+)e(-) or Z→μ(+)μ(-) candidate and at least two jets, including at least one jet identified as likely to contain a b quark. To validate the search procedure, we also measure the cross section for ZZ production in the same final state. It is found to be consistent with its SM prediction. We set upper limits on the ZH production cross section times branching ratio for H→bb at the 95% C.L. for Higgs boson masses 90 ≤ M(H) ≤ 150 GeV. The observed (expected) limit for M(H) = 125 GeV is 7.1 (5.1) times the SM cross section.

Evidence for a particle produced in association with weak bosons and decaying to a bottom-antibottom quark pair in higgs boson searches at the tevatron

We combine searches by the CDF and D0 Collaborations for the associated production of a Higgs boson with a W or Z boson and subsequent decay of the Higgs boson to a bottom-antibottom quark pair. The data, originating from Fermilab Tevatron pp collisions at √s = 1.96 TeV, correspond to integrated luminosities of up to 9.7 fb(-1). The searches are conducted for a Higgs boson with mass in the range 100-150 GeV/c(2). We observe an excess of events in the data compared with the background predictions, which is most significant in the mass range between 120 and 135 GeV/c(2). The largest local significance is 3.3 standard deviations, corresponding to a global significance of 3.1 standard deviations. We interpret this as evidence for the presence of a new particle consistent with the standard model Higgs boson, which is produced in association with a weak vector boson and decays to a bottom-antibottom quark pair.

Search for violation of Lorentz invariance in top quark pair production and decay

Using data collected with the D0 detector at the Fermilab Tevatron Collider, corresponding to 5.3 fb(-1) of integrated luminosity, we search for violation of Lorentz invariance by examining the tt[over ¯] production cross section in lepton+jets final states. We quantify this violation using the standard-model extension framework, which predicts a dependence of the tt[over ¯] production cross section on sidereal time as the orientation of the detector changes with the rotation of the Earth. Within this framework, we measure components of the matrices (c(Q))(μν33) and (c(U))(μν33) containing coefficients used to parametrize violation of Lorentz invariance in the top quark sector. Within uncertainties, these coefficients are found to be consistent with zero.

Development and application of a loop-mediated isothermal amplification assay for rapid detection of Borrelia burgdorferi s. l. in ticks

A loop-mediated isothermal amplification (LAMP) assay was developed to detect Borrelia burgdorferi s. l. in ticks, which is a pathogen that causes Lyme disease. Cross-reactions with Chlamydia psittaci, Mycoplasma mycoides subsp. capri and some tick-borne pathogens were excluded. Analytical sensitivity of LAMP showed its detection limit was from 0.02 to 0.2 pg of DNA in detection of the reference samples at 65°C for 40 min. The performance of LAMP was assessed by testing 110 samples from susceptible tick species and comparing the results with conventional and nested PCR tests previously described. The results demonstrated that LAMP was significantly more sensitive than the conventional PCR (32.7% versus 15.5%, P < 0.05) and slightly more sensitive, although not significantly so, than nested PCR (32.7% versus 26.4%, P > 0.05). The assay was used to analyse a total of 1052 ticks collected from eight provinces in China. The results showed that the infection rates of B. burgdorferi s. l. varied from 12.5% to 88.9% across the different geographical sites. Selected positive samples were subjected to sequencing and sequence analysis for conformation of the accuracy of the assay. Here we report a highly sensitive, specific and easy diagnostic assay based on LAMP technology. These data indicate that LAMP is a useful approach for detecting B. burgdorferi s. l. in field-collected ticks and has the potential as an alternative tool for the ecological and epidemiological surveillance of Lyme disease.