Contingent negative variation: a biomarker of abnormal attention in functional movement disorders.

BACKGROUND AND PURPOSE: Contingent negative variation (CNV) is a negative cortical wave that precedes a pre-cued imperative stimulus requiring a quick motor response. It has been related to motor preparation and anticipatory attention. The aim was to ascertain whether the clinical improvement of functional movement disorders after physiotherapy would be associated with faster reaction times and modulation of CNV. METHODS: Motor performance and CNV were analysed during a pre-cued choice reaction time task with varying cue validity. Twenty-one patients with functional movement disorders and 13 healthy controls at baseline were compared. Patients then underwent physiotherapy. At follow-up after physiotherapy, patients were categorized as clinically improved (responders) or not improved (non-responders) and retested. RESULTS: At baseline, patients did not generate CNV, contrary to controls [mean amplitude (µV) at the end of preparation to move: patients -0.47 (95% CI -1.94, 1.00) versus controls -2.59 (95% CI -4.46, -0.72)]. Responders performed faster after physiotherapy [mean natural logarithm (ln) reaction time (RT) (ms): follow-up 6.112 (95% CI 5.923, 6.301) versus baseline 6.206 (95% CI 6.019, 6.394), P = 0.010], contrary to non-responders. Simultaneously, responders showed a recovery of CNV after physiotherapy [follow-up -1.95 (95% CI -3.49, -0.41) versus baseline -0.19 (95% CI -1.73, 1.35), P < 0.001], contrary to non-responders [follow-up -0.32 (95% CI -1.79, 1.14) versus baseline -0.72 (95% CI -2.19, 0.75), P = 0.381]. CONCLUSIONS: Clinical improvement of functional movement disorders after physiotherapy was associated with faster reaction times and normalization of CNV, which was absent at baseline. These findings suggest that CNV may constitute a useful neurophysiological biomarker related to abnormal attention in functional movement disorders.

Use of Density Functional Based Tight Binding Methods in Vibrational Circular Dichroism.

Vibrational circular dichroism (VCD) is a spectroscopic technique used to resolve the absolute configuration of chiral systems. Obtaining a theoretical VCD spectrum requires computing atomic polar and axial tensors on top of the computationally demanding construction of the force constant matrix. In this study we evaluated a VCD model in which all necessary quantities are obtained with density functional based tight binding (DFTB) theory. The analyzed DFTB parametrizations fail at providing accurate vibrational frequencies and electric dipole gradients but yield reasonable normal modes at a fraction of the computational cost of density functional theory (DFT). Thus, by applying DFTB in composite methods along with DFT, we show that it is possible to obtain accurate VCD spectra at a much lower computational demand.

Frequency Range Selection Method for Vibrational Spectra.

Theoretical calculations of vibrational properties are widely used to explain and predict experimental spectra. However, with standard quantum chemical methods all molecular motions are considered, which is rather time-consuming for large molecules. Because typically only a specific spectral region is of experimental interest, we propose here an efficient method that allows calculation of only a selected frequency interval. After a computationally cheap low-level estimate of the molecular motions, the computational time is proportional to the number of normal modes needed to describe this frequency range. Results for a medium-sized molecule show a reduction in computational time of up to 1 order of magnitude with negligible loss in accuracy. We also show that still larger computational savings are possible by using an additional intensity-selection procedure.

Psittacara leucophthalmus (Aves: Psittacidae) como um novo hospedeiro de Paratanaisia bragai (Trematoda: Eucotylidae) no Brasil: achados clínicos e patológicos: relato de caso / Psittacara leucophthalmus as a new host of Paratanaisia bragai (Trematoda: Eucotylidae) in Brazil: clinical and pathological findings: case report

Paratanaisia bragai é um trematódeo que parasita rins e ureteres de aves domésticas e selvagens. Apesar de considerado pouco patogênico pode levar a complicações clínicas e morte em infecções severas. No presente estudo, um caso de parasitismo fatal em maritaca (Psittacara leucophthalmus) por P. bragai é relatado. A ave, oriunda da área urbana do município de Lavras, Minas Gerais, Brasil, teve manifestações clínicas de apatia, desidratação, dispneia e veio a óbito. Na necropsia foram observados rins aumentados de volume, pálidos, com superfície irregular e nodulações esbranquiçadas. Ao corte verificaram-se parasitos nos rins, que foram processados para montagem de lâminas permanentes e identificados segundo técnica de rotina como P. bragai. No exame histopatológico dos rins foram constatados infiltrado inflamatório linfoplasmocítico multifocal moderado, dilatação de túbulos e focos de regeneração tubular, associados a fibrose intersticial moderada no córtex renal. Na medula renal havia infiltrado de macrófagos, heterófilos, eosinófilos e células gigantes multinucleadas associado a parasitos em ductos coletores dilatados. O parasitismo de P. leucophthalmus por P. bragai é relatado pela primeira vez. A importância de se considerar este parasito entre as possibilidades diagnósticas em aves com insuficiência renal é brevemente discutida.(AU)

Paratanaisia bragai is a trematode parasite of the kidneys and ureters of poultry and wild birds. Despite its low pathogenicity, this parasite can lead to several clinical complications and death in heavy infections. In the present study, a fatal case of parasitism by P. bragai in a specimen of the White-eyed Parakeet, Psittacara leucophthalmus, is reported. The bird, coming from the urban area of the county of Lavras, Minas Gerais, Brazil, was clinically evaluated and revealed apathy, dehydration, dyspnea, and death. The gross findings were pale and enlarged kidneys, which also had irregular surface with whitish nodulations. Parasites were observed on cutting surface of the renal parenchyma. They were processed for assembly of permanent slides and identified as P. bragai according to routine technique. The histologic findings were mild multifocal lymphoplasmacytic infiltrate, tubular dilatation and foci of tubular regeneration related to mild interstitial fibrosis in the renal cortex, and infiltration of macrophages, heterophils, eosinophils and multinucleated giant cells associated with metazoan parasites in the collecting ducts in renal medulla. The parasitism of P. leucophthalmus by P. bragai is reported for the first time. The importance of considering this parasite among the diagnostic possibilities in birds with renal insufficiency is briefly discussed.(AU)

Profile of hMSH2 expression in breast tumors and lymph nodes: a preliminary study.

OBJECTIVE: The mismatch repair (MMR) genes play a central role for the onset of cancer. One of these genes is hMSH2. A differential hMSH2 protein expression has been detected in the mononuclear fraction of peripheral blood of patients with breast cancer when compared to healthy women. This work aims to evaluate the expression of hMSH2 in patients diagnosed with breast cancer undergoing treatment at various stages of the disease to verify its potential use as a prognostic marker. PATIENTS AND METHODS: Immunohistochemical expression of hMSH2 at different stages of breast cancer in 40 patients biopsy samples were analyzed. RESULTS: hMSH2 has a considerable increased expression in all groups of patients with tumors, when compared to patients without tumors. CONCLUSIONS: immunohistochemistry indeed can be a great tool for the diagnosis of breast cancer, as it is an easy and versatile technique.

Electrochemical oxidation of imazapyr with BDD electrode in titanium substrate.

In this work we have studied the treatment of imazapyr by electrochemical oxidation with boron-doped diamond anode. Electrochemical degradation experiments were performed in a one-compartment cell containing 0.45 L of commercial formulations of herbicide in the pH range 3.0-10.0 by applying a density current between 10 and 150 mA cm(-2) and in the temperature range 25-45 °C. The maximum current efficiencies were obtained at lower current densities since the electrochemical system is under mass transfer control. The mineralization rate increased in acid medium and at higher temperatures. The treatment was able to completely degrade imazapyr in the range 4.6-100.0 mg L(-1), although the current charge required rises along with the increasing initial concentration of the herbicide. Toxicity analysis with the bioluminescent bacterium Vibrio fischeri showed that at higher pollutant concentrations the toxicity was reduced after the electrochemical treatment. To clarify the reaction pathway for imazapyr mineralization by OH radicals, LC-MS/MS analyses we performed together with a theoretical study. Ions analysis showed the formation of high levels of ammonium in the cathode. The main final products of the electrochemical oxidation of imazapyr with diamond thin film electrodes are formic, acetic and butyric acids.