X-ray Diffraction of Water in Polyvinylpyrrolidone.

PVP is a hydrophilic polymer commonly used as an excipient in pharmaceutical formulations. Here we have performed time-resolved high-energy X-ray scattering experiments on pellets of PVP at different humidity conditions for 1-2 days. A two-phase exponential decay in water sorption is found with a peak in the differential pair distribution function at 2.85 Å, which is attributed to the average (hydrogen bonded) carbonyl oxygen-water oxygen distance. Additional scattering measurements on powders with fixed compositions ranging from 2 to 12.3 wt % H2O were modeled with Empirical Potential Structure Refinement (EPSR). The models reveal approximately linear relations between the carbonyl oxygen-water oxygen coordination number (nOC-OW) and the water oxygen-water oxygen coordination number (nOW-OW) versus water content in PVP. A stronger preference for water-water hydrogen bonding over carbonyl-water bonding is found. At all the concentrations studied the majority of water molecules were found to be randomly isolated, but a wide distribution of coordination environments of water molecules is found within the PVP polymer strands at the highest concentrations. Overall, the EPSR models indicate a continuous evolution in structure versus water content with nOW-OW=1 occurring at ∼12 wt % H2O, i.e., the composition where, on average, each water molecule is surrounded by one other water molecule.

Relationship between pulmonary rehabilitation and care dependency in COPD.

The aims of this study were to explore care dependency before and after pulmonary rehabilitation (PR) in patients with COPD (n=331) and to compare the response to PR between care dependent and independent patients. At baseline, 85 (25.7%) patients had a Care Dependency Scale (CDS) score ≤68 points and were considered as care dependent. CDS scores of these patients improved after PR (p<0.001). After PR, CDS score of 38 (44.7%) patients with a baseline CDS score ≤68 points increased to >68 points. Patients with a baseline CDS score ≤68 points or >68 points showed after PR a comparable improvement in COPD Assessment Test, Hospital Anxiety and Depression Scale and 6-min walk distance (all p<0.05). TRIAL REGISTRATION NUMBER: NTR3416 (The Netherlands).

Hard x-ray methods for studying the structure of amorphous thin films and bulk glassy oxides.

High-energy photon diffraction minimizes many of the corrections associated with laboratory x-ray diffractometers, and enables structure factor measurements to be made over a wide range of momentum transfers. The method edges us closer toward an ideal experiment, in which coordination numbers can be extracted without knowledge of the sample density. Three case studies are presented that demonstrate new hard x-ray methods for studying the structure of glassy and amorphous materials. First, the methodology and analysis of high-energy grazing incidence on thin films is discussed for the case of amorphous In2O3. The connectivity of irregular InO6polyhedra are shown to exist in face-, edge- and corner-shared configurations in the approximate ratio of 1:2:3. Secondly, the technique of high-energy small and wide angle scattering has been carried out on laser heated and aerodynamically levitated samples of silica-rich barium silicate (20BaO:80SiO2), from the single phase melt at 1500oC to the phase separated glass at room temperature. Based on Ba-O coordination numbers of 6 to 7, it is argued that the although the potential of Ba is ionic, it is weak enough to cause the liquid-liquid immiscibility to become metastable. Lastly, high-energy small and wide angle scattering has also been applied to high water content (up to 12 wt.%) samples of hydrous SiO2glass quenched from 1500oC at 4 GPa. An increase of Si1-O2correlations at 4.3 Å is found to be consistent with an increase in the population of three-membered SiO4rings at the expense of larger rings.

Apoptosis, proliferation and inflammatory infiltration in ANCA-positive glomerulonephritis.

AIMS: Antineutrophil cytoplasmic antibodies (ANCA) are detected in most patients with crescentic glomerulonephritis and necrotizing small vessel vasculitis. ANCA cause renal inflammation and proliferation. Apoptosis is necessary for resolution of inflammation. We studied apoptosis, apoptosis-regulating proteins, proliferation and infiltration with ANCA target antigen containing neutrophils and monocytes in renal biopsies from ANCA patients and disease controls. METHODS: Skin biopsies from patients with leukocytoclastic vasculitis (n=6) and renal biopsies from patients with ANCA vasculitis (n=10), ANCA-negative crescentic glomerulonephritis (CGN, n=7), mesangio-proliferative GN (n=6), post-streptococcal GN (PSGN, n=4), diabetic nephropathy (n=6) and minimal change nephropathy (MCNP, n=6) were evaluated by immunohistochemistry. Biopsies were stained for apoptosis (TdT-mediated UTP nick-end labeling, TUNEL), proliferation (Ki-67), neutrophils (NP 57), and monocytes (KP 1). We also evaluated Fas and Bcl-2 expression. RESULTS: Apoptosis was common in leukocytoclastic vasculitis skin biopsies, but was rare in renal biopsies. ANCA-positive NCGN showed the lowest apoptosis rate, similar to MCNP and diabetic nephropathy. The highest apoptosis rate was seen in PSGN. The highest glomerular Bcl-2 expression was present in ANCA-positive biopsies. The Bcl-2/TUNEL ratio was significantly increased in ANCA-positive necrotizing crescentic glomerulonephritis (NCGN) compared to ANCA-negative CGN and PSGN. When proliferation (Ki-67) and apoptosis were expressed as a ratio, we observed the highest index in biopsies from patients with ANCA-positive NCGN because of their low apoptosis rates. Finally, the glomerular inflammatory infiltrate in ANCA-positive NCGN showed a high percentage of neutrophils. CONCLUSIONS: These preliminary results suggest an imbalance between apoptosis and proliferation, favoring proliferation, in renal biopsies from ANCA-positive NCGN patients.

Amperometric detection of heavy metal ions in ion pair chromatography at an array of water/nitrobenzene micro interfaces.

A novel amperometric detector for heavy metal ions has been developed and successfully applied for ion pair chromatography. The detector is based on the electrochemical transfer of the metal ions across an array of water/nitrobenzene micro interfaces. The ion transfer is facilitated by the neutral ionophores methylenebis(diphenylphosphineoxide) and methylenebis(di- phenylphosphinesulfide). More than eight metals are separated in less than 15 min on an RP18 column using octyl sulfonate as ion pair reagent. For the heavy metals, the limits of decision are 19(Pb(2+)), 9(Zn(2+)), 9l (Co(2+)), 8(Cd(2+)) and 1.6(Mn(2+)) microg/L. The applicability of the new method for water samples is demonstrated.

Multidimensional encoding strategy of spiking neurons.

Neural responses in sensory systems are typically triggered by a multitude of stimulus features. Using information theory, we study the encoding accuracy of a population of stochastically spiking neurons characterized by different tuning widths for the different features. The optimal encoding strategy for representing one feature most accurately consists of narrow tuning in the dimension to be encoded, to increase the single-neuron Fisher information, and broad tuning in all other dimensions, to increase the number of active neurons. Extremely narrow tuning without sufficient receptive field overlap will severely worsen the coding. This implies the existence of an optimal tuning width for the feature to be encoded. Empirically, only a subset of all stimulus features will normally be accessible. In this case, relative encoding errors can be calculated that yield a criterion for the function of a neural population based on the measured tuning curves.

[Symptom portrayal and initial therapeutic relationship of female and male patients in the initial psychoanalytic interview]. / Symptomschilderungen und initiale Beziehungsangebote von weiblichen und männlichen Patienten in psychoanalytischen Erstinterviews.

The transcripts of psychoanalytic initial interviews are analyzed in using the "Structural Analysis of Social Behavior" (SASB) by L. S. Benjamin. This instrument was chosen to detect how male and female patients talk about their symptoms, and about previous treatments. The immediate interaction with the interviewer during the dialogue was also described by using SASB. On the basis of only the first patients' utterances after the initial request of the therapists (like "What brings you here?") we can distinguish female and male patients by the quality of the relations described (to the symptoms, the previous physicians, and to the therapist). The sex-specific readiness to establish relationships which becomes apparent in these descriptions can be related to the interview situation itself. In our further argumentation we interpret them as subtle messages to the interviewer. Finally we discuss their inherent potentials and risks for the psychotherapeutic cooperation.

[How do patients develop after inpatient psychotherapy?]. / Wie entwickeln sich Patienten im Anschluss an eine stationäre Psychotherapie?

The following study examines the attitudes six months after stationary psychotherapeutic treatment of 82 patients examined on a monthly basis. The image presented is consistently positive with regard to improvement in both physical and psychological symptoms, changes in abnormal behavior, the relationship to partners and other people, and with regard to the satisfaction with therapy itself. Complementing the statistical results are citations from lengthy written evaluations by the patients of their stay in the hospital and the influence it has had on their current situation.