Observation of electron neutrino appearance in a muon neutrino beam

The T2K experiment has observed electron neutrino appearance in a muon neutrino beam produced 295 km from the Super-Kamiokande detector with a peak energy of 0.6 GeV. A total of 28 electron neutrino events were detected with an energy distribution consistent with an appearance signal, corresponding to a significance of 7.3σ when compared to 4.92±0.55 expected background events. In the Pontecorvo-Maki-Nakagawa-Sakata mixing model, the electron neutrino appearance signal depends on several parameters including three mixing angles θ12, θ23, θ13, a mass difference Δm(32)(2) and a CP violating phase δ(CP). In this neutrino oscillation scenario, assuming |Δm(32)(2)|=2.4×10(-3)  eV(2), sin(2)θ(23)=0.5, and Δm322>0 (Δm(32)(2)<0), a best-fit value of sin(2)2θ(13)=0.140(-0.032)(+0.038) (0.170(-0.037)(+0.045)) is obtained at δ(CP)=0. When combining the result with the current best knowledge of oscillation parameters including the world average value of θ(13) from reactor experiments, some values of δ(CP) are disfavored at the 90% C.L.

Characterization of neuromyelitis optica and neuromyelitis optica spectrum disorder patients with a late onset

BACKGROUND

Few data are available for patients with a late onset (≥ 50 years) of neuromyelitis optica (LONMO) or neuromyelitis optica spectrum disease (LONMOSD), defined by an optic neuritis/longitudinally extensive transverse myelitis with aquaporin-4 antibodies (AQP4-Ab).

OBJECTIVE

To characterize LONMO and LONMOSD, and to analyze their predictive factors of disability and death.

METHODS

We identified 430 patients from four cohorts of NMO/NMOSD in France, Germany, Turkey and UK. We extracted the late onset patients and analyzed them for predictive factors of disability and death, using the Cox proportional model.

RESULTS

We followed up on 63 patients with LONMO and 45 with LONMOSD during a mean of 4.6 years. This LONMO/LONMOSD cohort was mainly of Caucasian origin (93%), women (80%), seropositive for AQP4-Ab (85%) and from 50 to 82.5 years of age at onset. No progressive course was noted. At last follow-up, the median Expanded Disability Status Scale (EDSS) scores were 5.5 and 6 in the LONMO and LONMOSD groups, respectively. Outcome was mainly characterized by motor disability and relatively good visual function. At last follow-up, 14 patients had died, including seven (50%) due to acute myelitis and six (43%) because of opportunistic infections. The EDSS 4 score was independently predicted by an older age at onset, as a continuous variable after 50 years of age. Death was predicted by two independent factors: an older age at onset and a high annualized relapse rate.

CONCLUSION

LONMO/LONMOSD is particularly severe, with a high rate of motor impairment and death.

Measurement of neutrino oscillation parameters from muon neutrino disappearance with an off-axis beam

The T2K Collaboration reports a precision measurement of muon neutrino disappearance with an off-axis neutrino beam with a peak energy of 0.6 GeV. Near detector measurements are used to constrain the neutrino flux and cross section parameters. The Super-Kamiokande far detector, which is 295 km downstream of the neutrino production target, collected data corresponding to 3.01×10(20) protons on target. In the absence of neutrino oscillations, 205±17 (syst) events are expected to be detected while only 58 muon neutrino event candidates are observed. A fit to the neutrino rate and energy spectrum, assuming three neutrino flavors and normal mass hierarchy yields a best-fit mixing angle sin2(θ23)=0.514±0.082 and mass splitting |Δm(32)(2)|=2.44(-0.15)(+0.17)×10(-3) eV2/c4. Our result corresponds to the maximal oscillation disappearance probability.

Brainstem manifestations in neuromyelitis optica: a multicenter study of 258 patients

BACKGROUND

Neuromyelitis optica (NMO) is a severe autoimmune disease of the central nervous system characterized by spinal cord and optic nerve involvement. Brainstem manifestations have recently been described.

OBJECTIVE

To evaluate the time of occurrence, the frequency and the characteristics of brainstem symptoms in a cohort of patients with NMO according to the ethnic background and the serologic status for anti-aquaporin-4 antibodies (AQP4-abs).

METHODS

We performed a multicenter study of 258 patients with NMO according to the 2006 Wingerchuk criteria and we evaluated prospectively the frequency, the date of onset and the duration of various brainstem signs in this population.

RESULTS

Brainstem signs were observed in 81 patients (31.4%). The most frequently observed signs were vomiting (33.1%), hiccups (22.3%), oculomotor dysfunction (19.8%), pruritus (12.4%), followed by hearing loss (2.5%), facial palsy (2.5%), vertigo or vestibular ataxia (1.7%), trigeminal neuralgia (2.5%) and other cranial nerve signs (3.3%). They were inaugural in 44 patients (54.3%). The prevalence was higher in the non-Caucasian population (36.6%) than in the Caucasian population (26%) (p<0.05) and was higher in AQP4-ab-seropositive patients (32.7%) than in seronegative patients (26%) (not significant).

CONCLUSIONS

This study confirms the high frequency of brainstem symptoms in NMO with a majority of vomiting and hiccups. The prevalence of these manifestations was higher in the non Caucasian population.

Acute pancreatitis in pregnancy: review of three cases and anaesthetic management

Acute pancreatitis is rare in pregnancy, with an estimated incidence of 1 in 1000-3000 pregnancies. Gallstones are the commonest cause. Mortality and morbidity associated with pancreatitis have declined as diagnosis and management options improve. Presentation usually occurs in the third trimester or early postpartum period with severe epigastric pain, nausea, vomiting, anorexia and fever. Blood investigations show an elevated white cell count and increased liver enzyme concentrations. Ultrasound is safe but has lower sensitivity than computerised tomography for detecting gallstones. Management during pregnancy has traditionally been conservative, followed by cholecystectomy after delivery. Recurrence of pancreatitis during pregnancy may necessitate more urgent surgery. The second trimester is considered the safest for surgery, with early involvement of intensive care as the condition can deteriorate rapidly. We present three cases managed in our unit over a six-month period that illustrate the spectrum of disease and the successful use of a multidisciplinary team approach.

P2-01-02: Pharmacological Inhibition of RANKL Attenuates Mammary Tumor Development and Lung Metastases in the MMTV-neu Transgenic Spontaneous Tumor Model

Background: RANK and its ligand (RANKL), key factors for bone remodeling and metastasis, are crucial for the development of mouse mammary glands during pregnancy. In a mouse model of mammary carcinogenesis induced by the hormone medroxyprogesterone (MPA) and a carcinogen (DMBA), treatment with a RANKL inhibitor RANK-Fc reduces hormone-induced mammary epithelial proliferation, incidence of preneoplasias, and mammary adenocarcinomas. This study assessed the expression of mouse RANK and RANKL in FVB wild-type (WT) and MMTV-neu mice and whether RANKL inhibition could inhibit mammary tumor formation and lung metastases in this model.

Materials and Methods: MMTV-neu mice were treated with the RANKL inhibitor RANK-Fc (10 mg/kg, 3x/week) or vehicle (muFc) beginning at 20 weeks. Mammary tumor formation was determined by palpation and confirmed by histologic examination. The presence of preneoplastic lesions and histotype of tumors was determined on H&E-stained tissues. Entire lungs from tumor-bearing MMTV-neu mice were step-sectioned at 75 μm and assessed histologically for the presence of metastases. Epithelial proliferation was measured by BrdU labeling of the mammary epithelium. The expression of RANK, RANKL, cyclin D1, progesterone receptor (PR), F4/80, FOXP3, and CD3 was determined by immunohistochemistry (IHC).

Results: RANK-Fc treatment of MMTV-neu mice resulted in a significant reduction in total number of mammary tumors and lung metastases quantified at necropsy but did not impact median time to spontaneous mammary tumor onset. RANKL inhibition resulted in reduced pre-neoplasias and corresponding reductions in proliferation and cyclin D1 within normal mammary epithelia but not in adenocarcinomas. Treatment of MMTV-neu mice with RANK-Fc also reduced the incidence and number of lung metastases per mouse. RANK protein was detected in normal mammary epithelium, preneoplastic mammary intraepithelial neoplasia (MIN), the epithelial component of adenocarcinomas and lung metastases, and monocytic element adjacent to primary MMTV-neu tumors. RANKL protein was detected in normal mammary epithelium but not in the epithelia, stromal component or infiltrating cells of adenocarcinomas or lung metastases. Progesterone receptor expression was observed in normal mammary epithelium of MMTV-neu and FVB WT mice but decreased over time in MMTV-neu mice and was not detected in preneoplasias, adenocarcinomas, or lung metastases. CD3 was detected in mammary tumors and lung metastases but neither RANKL nor FOXP3 were present. Staining of lymph nodes was used as a positive control for RANKL and FOXP3. Expression of FOXP3 and RANKL were not measurably colocalized in dual staining of lymph nodes.

Discussion: RANKL is expressed in normal mammary epithelia of MMTV-neu mice but is not detected in any stage of atypia, including MIN, mammary adenocarcinoma, or lung metastases. Selective pharmacological inhibition of RANKL by RANK-Fc treatment attenuated mammary tumor development and lung metastases in the MMTV-neu transgenic spontaneous tumor model.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-01-02.

Torsion stiffness of a protein pair determined by magnetic particles

We demonstrate the ability to measure torsion stiffness of a protein complex by applying a controlled torque on a magnetic particle. As a model system we use protein G bound to an IgG antibody. The protein pair is held between a magnetic particle and a polystyrene substrate. The angular orientation of the magnetic particle shows an oscillating behavior upon application of a rotating magnetic field. The amplitude of the oscillation increases with a decreasing surface coverage of antibodies on the substrate and with an increasing magnitude of the applied field. For decreasing antibody coverage, the torsion spring constant converges to a minimum value of 1.5 × 10(3) pN·nm/rad that corresponds to a torsion modulus of 4.5 × 10(4) pN·nm(2). This torsion stiffness is an upper limit for the molecular bond between the particle and the surface that is tentatively assigned to a single protein G-IgG protein pair. This assignment is supported by interpreting the measured stiffness with a simple mechanical model that predicts a two orders of magnitude larger stiffness for the protein G-IgG complex than values found for micrometer length dsDNA. This we understand from the structural properties of the molecules, i.e., DNA is a long and flexible chain-like molecule, whereas the antibody-antigen couple is orders of magnitude smaller and more globular in shape due to the folding of the molecules.

Spectrofluorimetric method for determination of citalopram in bulk and pharmaceutical dosage forms

A simple accurate, sensitive reproducible spectrofluorimetric method was developed for the analysis of citalopram in pure and pharmaceutical dosage form. Citalopram showed strong native fluorescence in 0.05 M sulphuric acid having excitation at 239 nm and emission at 300 nm. All parameters like the effect of different solvents, pH, dilutions, reaction time, temperature and effect of excipients were thoroughly investigated. The calibration graph was linear in the range from 0.100 to 0.900 μg/ml. The proposed method was statistically validated and successfully applied for analysis of tablet dosage forms. The percentage recovery was found to be between 99.08% to 99.28%.