Quantification of proteins and metabolites by mass spectrometry without isotopic labeling or spiked standards

A new method is presented for quantifying proteomic and metabolomic profile data by liquid chromatography-mass spectrometry (LC-MS) with electrospray ionization. This biotechnology provides differential expression measurements and enables the discovery of biological markers (biomarkers). Work presented here uses human serum but is applicable to any fluid or tissue. The approach relies on linearity of signal versus molecular concentration and reproducibility of sample processing. There is no use of isotopic labeling or chemically similar standard materials. Linear standard curves are reported for a variety of compounds introduced into human serum. As a measure of analytical reproducibility for proteome and metabolome sampling, median coefficients of variation of 25.7 and 23.8%, respectively, were determined for approximately 3400 molecular ions (not counting their numerous isotopes) from 25 independently processed human serum samples, corresponding to a total of 85000 individual molecular ion measurements.     

A novel model-based hearing compensation design using a gradient-free optimization method

We propose a novel model-based hearing compensation strategy and gradient-free optimization procedure for a learning-based hearing aid design. Motivated by physiological data and normal and impaired auditory nerve models, a hearing compensation strategy is cast as a neural coding problem, and a Neurocompensator is designed to compensate for the hearing loss and enhance the speech. With the goal of learning the Neurocompensator parameters, we use a gradient-free optimization procedure, an improved version of the ALOPEX that we have developed, to learn the unknown parameters of the Neurocompensator. We present our methodology, learning procedure, and experimental results in detail; discussion is also given regarding the unsupervised learning and optimization methods.     

Mössbauer Studies in the Mechanochemistry of Spinel Ferrites

Mössbauer spectroscopy can provide information on a large variety of mechanochemical processes in solids. In this overview, selected examples are presented of Mössbauer studies of homogeneous and heterogeneous mechanochemical reactions in spinel ferrites. Several interesting features are involved in the work, e.g., mechanically induced cation redistributions, changes of nearest-neighbor configurations, superparamagnetic relaxation, spin-canting effects, as well as formation and redox reactions. The considerable literature on mechanically treated spinel ferrites is reviewed. Despite numerous efforts, the understanding of the nonequilibrium mechanochemical processes in spinel ferrites is considered to be far from complete.     

Remission ratio of chronic urticaria--"spontaneous" healing or result of eradication of Helicobacter pylori?

Helicobacter pylori infection has been assumed to be the underlying cause of some dermatological diseases such as, chronic urticaria. In order to investigate this problem we interviewed 55 patients with chronic urticaria concerning the state of the disease approximately 10 months after being discharged from hospital. After an additional six months we interviewed them for a second time and thus determined the remission ratio. There was no significant evidence showing that a link exists between urticaria and proven Helicobacter pylori infection (chi 2-Test). There was also no significant correlation in the remission ratio between patients treated with a triple therapy and non-treated patients (exact Fisher-Test).     

"Sociosomatics": the contributions of anthropology to psychosomatic medicine

We report an unusual case of T 0 N 2 M 0 small cell lung cancer in a patient with Lambert-Eaton myasthenic syndrome (LEMS). A 52-year-old man began to notice muscle weakness in a left limb in January 1996, which was followed by muscle weakness in his left arm and fingers, appetite loss, and general fatigue. An electromyogram (EMG) showed the waxing phenomenon in response to high-frequency repetitive stimulation. Lambest-Eaton myasthenic syndrome was diagnosed, based on his symptoms and EMG findings. Chest computed tomography (CT) was done, and left paratracheal, tracheobronchial, subaortic, and hilar lymphadenopathy were found. No mass was seen in either lung field. Cytologic examination of the sputum and bronchial lavage fluid were done, but no malignant cells were found Small cell lung cancer was diagnosed after thoracoscopic resection of the subaortic lymph nodes. No metastases were detected by bone scintigraphy, abdominal CT, or magnetic resonance imaging of the brain. Complete response and resolution of symptoms were obtained by chemotherapy and irradiation.     

Viskoelastische Eigenschaften von Buchenholz bei periodischer Biegebeanspruchung

The time-dependent modulus and the relevant mechanical loss factor of beech wood were determined by means of sinusoídal bending stress cycles ranging from some minutes up to a few months (10^?2 to 10^?7 cycles per second). After a survey of the linear theory of viscoelasticity the testing method and the devices used are described. Further the experimental results are presented by graphic plots of the moduli and loss factors at temperatures of 22, 40, 70, and 90°C and moisture contents of 12, 20, and 30% as a function of time from 10² up to 10⁷ s. The results are discussed as a part (region of dispersion) of the retardation spectrum consisting of a number of viscoelastic processes.     

Adrenal medulla graft induced recovery of function in an animal model of Parkinson's disease: Possible mechanisms of action.

Reviews evidence suggesting at least 3 fundamental processes that may underlie the functional effects of adrenal medulla grafts. These include (1) increased permeability of the blood-brain barrier to dopamine (DA); (2) increased serum DA concentrations; and (3) changes in extracellular concentrations of DA and dihydroxyphenylacetic acid in the host brain resulting in a restoration of symmetry in the striatal DA system. Five hypotheses are proposed to explain the behavioral effects of adrenal medulla grafts in light of these processes. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)