A simple setup for in situ alkali metal electronic spin polarimetry.

Faraday rotation is considered a gold standard measurement of the electronic spin polarization of an alkali metal vapor produced under optical pumping. However, during the production of large volumes of hyperpolarized xenon gas, transmission monitoring measurements, otherwise known as field cycling measurements, are generally employed to measure the spin polarization of alkali metal atoms in situ as this method is easier to implement than Faraday rotation on standard polarizer setups. Here, we present a simple, low-cost experimental setup to perform Faraday rotation measurements of the electronic spin polarization of alkali metal atoms that can be easily implemented on standard polarizer setups. We then compare Rb polarization measurements obtained with the Faraday rotation method to those obtained with the transmission monitoring method. To our knowledge, a direct comparison of these methods has never been made. Overall, we found good agreement between the two methods, but at low Rb density and high laser power, we found evidence of nonlinear magneto-optical effects that may prevent Faraday rotation from being used under these conditions.

microRNAs with AAGUGC seed motif constitute an integral part of an oncogenic signaling network.

microRNA (miRNA) dysregulation is a common feature of cancer cells, but the complex roles of miRNAs in cancer are not fully elucidated. Here, we used functional genomics to identify oncogenic miRNAs in non-small cell lung cancer and evaluate their impact on response to epidermal growth factor (EGFR)-targeting therapy. Our data demonstrate that miRNAs with an AAGUGC motif in their seed sequence increase both cancer cell proliferation and sensitivity to EGFR inhibitors. Global transcriptomics, proteomics and target prediction resulted in the identification of several tumor suppressors involved in the G1/S transition as AAGUGC-miRNA targets. The clinical implications of our findings were evaluated by analysis of AAGUGC-miRNA expression in multiple cancer types, supporting the link between this miRNA seed family, their tumor suppressor targets and cancer cell proliferation. In conclusion, we propose the AAGUGC seed motif as an oncomotif and that oncomotif-miRNAs promote cancer cell proliferation. These findings have potential therapeutic implications, especially in selecting patients for EGFR-targeting therapy.

Autologous stem cell transplantation in a patient with severe systemic sclerosis.

UNLABELLED: Systemic Sclerosis (SSc) is a chronic disease of the connective tissue, whose pathogenesis involves abnormalities of the immunological system. It has a variable course and there is a subgroup of patients with rapidly progressive disease or unresponsive to conventional treatment. These patients can benefit from intensive immunosuppression and autologous hematopoietic stem cell transplant. CLINICAL CASE: 19-year-old (y.o.) woman diagnosed with SSc at the age of 13 y.o. with cutaneous, vascular and articular involvement with initial response to methotrexate. Three years later the disease progressed with severe digestive involvement (dysphagia, delayed gastric emptying and weight loss) needing gastrostomy for nutritional support. She was treated with cyclophosphamide without improvement In May 2012 she had an autologous transplant with myeloablative regimen (BEAM): carmustine 300 mg/m2x1 day; etoposido 120 mg/kgx4 days; cytarabine 120 mg/kg 12/12:hx4 days; melphalan 140 mg/m2x1 day. A year and a half after transplantation she is asymptomatic, without any signs or symptoms of the disease, feeds by mouth and the gastric emptying study is normal. Currently she is free of medication.

Revisiting the mean-field picture of dipolar effects in solution NMR.

For more than three decades, the classical or mean-field picture describing the distant dipolar field has been almost always simplified to an effective field proportional to the local longitudinal magnetization, differing only by a scale factor of 1.5 for homomolecular (identical resonance frequency) and heteromolecular interactions. We re-examine the underlying assumptions, and show both theoretically and experimentally that the mathematical framework needs to be modified for modern applications such as imaging. We demonstrate new pulse sequences which produce unexpected effects; for example, modulating an arbitrarily small fraction of the magnetization can substantially alter the frequency evolution. Thus, matched gradient pulse pairs (a seemingly innocuous module in thousands of existing pulse sequences) can alter the time evolution in highly unexpected ways, particularly with small flip angle pulses such as those used in hyperpolarized experiments. We also show that specific gradient pulse combinations can retain only dipolar interactions between unlike spins, and the dipolar field can generate a secular Hamiltonian proportional to I(x).

Clinical effectiveness of hyperbaric oxygen therapy for BK-virus-associated hemorrhagic cystitis after allogeneic bone marrow transplantation.

Late-onset hemorrhagic cystitis (HC) after allogeneic hematopoietic stem cell transplantation (HSCT) has been associated with BK virus (BKV). Antiviral drugs are of limited efficacy and the optimal treatment for HC has not yet been established. Hyperbaric oxygen (HBO) may benefit these patients. We, therefore, retrospectively evaluated the effectiveness of HBO therapy in 16 patients with HC after allogeneic HSCT. All 16 patients had macroscopic hematuria and BKV infection. Patients received 100% oxygen in a hyperbaric chamber at 2.1 atmospheres for 90 min, 5 days per week, with a median 13 treatments (range, 4-84). Fifteen patients (94%) showed complete resolution of hematuria. Median urinary DNA BKV titers declined after HBO (P<0.05). Patients started on HBO earlier after diagnosis of HC responded sooner (P<0.05). HBO was generally well tolerated and proved to be a reliable option for this difficult to manage condition.

Enhanced nonlinear magnetic resonance signals via square wave dipolar fields.

This report introduces a new approach that enhances nonlinear solution magnetic resonance signals from intermolecular dipolar interactions. The resulting signals can theoretically be as large as the full equilibrium magnetization. Simple, readily implemented pulse sequences using square-wave magnetization modulation simultaneously refocus all even order intermolecular multiple quantum coherences, leading to a substantial net signal enhancement, complex nonlinear dynamics, and improved structural sensitivity under realistic conditions.

[The identification of multiple thrombophilic risk factors in an infant with cerebrovascular accident]. / Múltiples factores de riesgo trombofílicos identificados en un lactante con accidente vascular cerebral.

INTRODUCTION: Neonatal stroke (NNS) incidence appears to be increasing over the last years. This is believed to be a consequence of diagnostic accuracy rather than a real amplification of this entity. Nowadays, NNS incidence is estimated to be 1:4000 full newborns. CASE REPORT: Child with left middle cerebral artery territory infarction in which several thromboembolic risk factors were documented both in the child (neonatal sepsis and factor V Leiden) and his mother (lupus anticoagulant, pre-eclampsy and factor V Leiden). CONCLUSIONS: This case supports the increasing evidence in recent reports that association of multiple prothrombotic risk factors (maternal and foetal) is present in NNS genesis. This way the authors agree that wide prothrombotic study may be of crucial interest in identifying subjacent thrombophilic disease, even when an exogenous risk factor is present.

Determination of neutrophil Fcgamma receptor IIIb antigens (HNA-1a, HNA-1b and HNA-1c) by fluorescence-primed allele-specific polymerase chain reaction.

We evaluate a technique for genotyping HNA-1a, -1b and -1c antigens, resorting to fluorescence-primed allele-specific polymerase chain reaction (FPAS-PCR), and determine the frequency of the different genotypes in a normal Portuguese population. Our results indicate that the FPAS-PCR system is a reliable and simple tool for genotyping the neutrophil Fcgamma receptor IIIB antigens. The HNA-1a, -1b and -1c gene frequencies of 42.98, 84.21 and 6.14%, respectively, found in this study are similar to those reported for other white populations.

Coexistence of congenital red cell pyruvate kinase and band 3 deficiency.

The authors report the case of a 9-year-old Caucasian girl, born in northern Portugal, with chronic nonspherocytic haemolytic anaemia and without family history of anaemia. The aethiological study of this anaemia revealed pyruvate kinase deficiency (PKD), because of two previously described mutations (426Arg-->Trp and 510Arg-->Gln). Since the blood smear revealed features not fully compatible with PKD diagnosis, additional tests were performed for the propositus and her parents, namely red blood cell membrane protein analysis. A decrease in proteins band 3 (15%) and 4.2 (18%) was found in the propositus. Her father presented only a decrease in band 3 (11%). Coexistence of PKD and erythrocyte membrane proteins deficiency in the same patient is very uncommon. Our findings suggest that a careful blood smear observation may lead to the identification of a combined deficiency in erythrocyte membrane proteins and enzymopathies.

New openings for porous systems research from intermolecular double-quantum NMR.

It has been recently recognized that residual intermolecular double-quantum coherences (iDQcs) provide a novel contrast mechanism to study heterogeneity in liquid systems. This is of much interest in the field of the physics of matter and biomedicine. Nowadays, literature concerning the behaviour of the iDQc signal originated by highly heterogeneous systems such as fluids in porous media is scarce. In this paper, we report and discuss our principal results about iDQc signal behaviour in confined liquid systems (trabecular bone, travertine, porous standard systems) and also some new results obtained on doped water in glass capillary pipes.

Intermolecular double-quantum NMR techniques to probe microstructures on porous media.

In heterogeneous systems the amplitude of the intermolecular double-quantum (DQ) signal depends on sample heterogeneity over a correlation distance dc=pi/(gammaGct). In this paper two different CRAZED-type sequences were applied in a porous medium phantom. One of these sequences gives rise to a DQ-T2 weighted signal, while the other one gives rise to a DQ-T2* weighted signal. Experimental results indicate that tuning of the correlation distance dc in a porous medium can alter the DQ signal in a manner which depends on the microstructure. This is evident only using the CRAZED-type sequence which gives rise to a DQ-T2* weighted signal.

[Bone marrow aplasia]. / Le aplasie midollari.

Aplastic anaemia is a haematological syndrome in which pancytopenia is due to a depletion, damage of inhibition of hemopoietic stem cells. The pathogenetic factors are still unclear: damage or inhibition of hemopoietic stem cells may be direct or indirect mediated through changes in the cellular humoral environment; evidence is accumulating that in some cases these processes are of autoimmune nature. The prognostic evaluation is based on hematological parameters at diagnosis: severe aplastic anemia (SAA) is defined by the following criteria: neutrophils less than 0.5 X 10(9)/l; reticulocytes less than 0.5 X 10(9)/l and platelets less than 20 X 10(9)/l. Survival rates in children with SAA are poor; the probability of survival at 1 year from diagnosis being 10%. In this form treatment is based on supportive therapy (transfusion and prevention of infections) and on a specific therapy: immunosuppression and/or BMT. BMT is reserved to patient with an HLA identical sibling donor and may be curative in 70-80% of cases. To date the use of antilymphocytoglobulin in SAA has also given satisfactory results with a favorable response in 50-60% of cases.