Properties of nanoporous organosilicate hybrid thin films with a bimodal pore size distribution

Low dielectric poly[methylsilsesquioxane‐ran‐trifluoropropylsilsesquioxane‐ran‐(2,4,6,8‐tetramethyl‐2,4,6,8‐tetraethylenecyclotetrasiloxane)silsesquioxane]s {P[M‐ran‐TFP‐ran‐(TCS)]SSQs} having various compositions were synthesized using trifluoropropyl trimethoxysilane, methyl trimethoxysilane and 2,4,6,8‐tetramethyl‐2,4,6,8‐tetra(trimethoxysilylethyl)cyclotetrasiloxane. The chemical composition of the polymers and the content of SiOH end‐groups were controlled by adjusting the reaction conditions, and they were characterized by ¹H‐NMR. The thermally decomposable trifluoropropyl groups on the P[M‐ran‐TFP‐ran‐(TCS)]SSQ backbone and heptakis(2,3,6‐tri‐O‐methyl)‐β‐cyclodextrin (CD) were employed as pore generators. The dielectric constants of the porous CD/P[M‐ran‐TFP‐ran‐(TCS)]SSQ films were in the range 2.0–2.7 (at 100 kHz) depending on the concentration of the porogens, and showed no change over 4 days under aqueous conditions. The pore size of the films showed a bimodal distribution, with diameters of ca 0.5–1.0 nm for those originating from the trifluoropropyl groups and 1.7 nm from the CD. The elastic modulus and hardness of the 30 vol% CD‐blended film with a dielectric constant of 2.26 were 2.40 and 0.38 GPa, respectively, as determined by a nanoindenter. Copyright © 2005 Society of Chemical Industry     

Treatment of schizophrenic psychoses with Lyorodin

Forty-four patients suffering from acute and chronic schizophrenic psychoses were used to obtain, by using Lorr's scale (IMPS) and taking the changes in disease state observed within three months as a base, suggestions or pointers as to the proper treatment of disease with fluphenazine (lyorodin) which is a neuroleptically highly potent phenothiazine derivative. Megalomania, grandiose delusions apathetic and depressive syndromes showed marked tendencies toward major improvement. An "antiautistic" effect was observed in chronic patients. The effective dose was between 6 and 12 mg a day. The drug was well tolerated. In the majority of cases it was also necessary for antiparkinsonian drugs to be administered to patients. After twelve months of treatment, slight to major improvements or even freedom from symptoms could be observed in 28 cases (or 64%).     

Effects of dextran, gelatine and homologous plasma on circulation in shock caused by severe anemia in the dog

Irreversible shock is produced in 28 anaesthetized mongrel dogs by withdrawal of erythrocytes and substitution by dextran, gelatine or plasma to an average Hb of 4.5g%. In contrast to other shock models cardiac output and perfusion pressure are not decreased by this preparation. In order to maintain arterial blood pressue above 90 mm Hg significantly more gelatine than dextran or serum has to be infused. There is no difference in hemodynamic responses after treatment with dextran or gelatine respectively. Both groups treated with colloidal solutions have the same survival rate of 38%. In the serum substituted dogs, however,survival rate is significantly greater (83%). Very likely this is due to a greater buffer capacity preventing severe acidosis, which is observed in the animals treated with colloidal solutions.     

Phospholipid membrane stabilization by dimethylsulfoxide and other inducers of Friend leukemic cell differentiation

A large number of low molecular weight polar cryoprotective agents have recently been found to induce erythroid differentiation of Friend leukemic cells in vitro. The effect of these agents on membrane fluidity in phospholipid vesicles was studied by determining the solid-to-liquid crystalline phase transition using differential scanning calorimetry. Some of the inducing agents studies were found to raise the normal transition temperature (Tc) by a few degrees. All of these agents were found to produce a separate transition at a much higher temperature. Changes in the head group of the phospholipid, the pH, the presence of divalent cations, and the addition of other membrane-active compounds were found to significantly influence the inducing agent's effects on the Tc of phospholipid membranes. The ability of the different agents to produce a new transition at a high temperature was found to correlate well with their ability to induce Friend leukemic cell differentiation. The possible mechansims of action of the chemical inducers, and the significance of the observed membrane effects on differentiation and malignancy are discussed. It is concluded that inducing agents decrease the fluidity and stabilize phospholipid membranes, and that their effects in cell differentiation might be initiated by a similar change in the properties of cell membranes.     

Therapeutic problems in postoperative keratopathy (author's transl)

Keratopathy following intraocular surgery is usually a neglegible transitory lesion which does not require special treatment. An intractible bullous keratopathy frequently develops in cases of endothelial dystrophy. Other causative factors leading to postoperative keratopathy are excessive operative traumatisation of the cornea, vitreocorneal adhesions, athalamia, detachment of Descemet's membrane or epithelial down-growth. For conservative treatment of postoperative keratopathies topical application of corticosteroids, acetylcholine, vitamine-A-ointments, hyperosmotic agents, soft contact lenses, and systemic application of carboanhydrase inhibitors can be used. According to our experience even in cases of severe keratopathy a significant improvement of visual acuity and discomfort may be achieved by long lasting and intensive conservative treatment. Only in rare cases one has to resort to glueing a contact lens on the cornea (Dohlman) or to perform a keratoplasty using Stocker's technique.     

How long are oral antidiabetic drugs effective?

Dopamine-beta-hydroxylase (DBH), the enzyme responsible for the biosynthesis of norepinephrine from dopamine was assayed in the blood serum of 23 normal adults, 16 patients with congestive heart failure, 19 patients with asymptomatic ischemic heart disease, 4 patients with angina pectoris at rest, 15 patients with essential hypertension, 8 patients with essential hypotension, 5 patients with neurocirculatory asthenia, and 9 normal adults before and after the exercise test. The serum DBH activity varied within a wide range in the control population. The DBH activity increased about 16% after the exercise stress. A tendency to increase DBH activity was shown in the patients with congestive heart failure. There was no significant difference between asymptomatic ischemic heart disease, essential hypertension and normal controls. A lower value was observed in the patients of angina pectoris at rest, while a higher DBH activity was demonstrated in the patients with essential hypotension. There was no significant difference between the neurocirculatory asthenia group and the normal control group.     

Binding of insulin analogs to partially purified insulin receptor from rat liver membrane (author's transl)

The insulin binding fraction was solubilized from rat liver membrane vesicles by triton and partially purified up to the specific binding activity of 2.1 pmol/mg. A further characteristic of the partially purified soluble receptor is a decrease in irreversible binding to 0.36% (+/- 0.28) with regard to total iodine insulin and to (+/- 1.8) in comparison to reversible binding. From Scatchard plots a high affinity binding site (KD = 5 X 10(-10)M) with low capacity (5 pmol/mg) and a low affinity binding site (KD = 3 X 10(-8) M) with high capacity (30 pmol/mg) can be seen. With carefully prepared liver membrane vesicles, the dissociation constant of the high affinity binding site from Scatchard plot is only 2 X 10(-9)M. With liver membrane vesicles, isolated for preparative purification procedure, the high affinity binding site could not be demonstrated. Displacement studies with insulin analogs were performed with [A1-D-alanine] insulin, [A1-L-alanine] insulin, [des-Gly-A1, NB1, NB29-(Msc)2]-insulin, proinsulin and [desoctapeptid B23-B30]-insulin. Results of binding measurements are presented in half-maximal iodo-insulin binding, in determination of inhibitor- and dissociation constants from Dixon-, Scatchard- and Lineweaver-Burk plots. There are equal relative binding potencies of analogs, observed with crude membrane vesicles and partially purified soluble receptor, although there is a 50-fold difference in specific binding activity. Biologically active insulins are characterized by strong binding to the high affinity binding site. The binding to the low affinity binding site is not correlated to the biological activity of the insulin analog. With insulin and biologically responsive analogs a non-linear curve in the double-reciprocal Lineweaver-Burk plot can be observed. Analogs with low biological activity show a linear dependency. Functional interactions of insulin with the receptor can be demonstrated in a high affinity binding with the first binding site of the Scatchard plot and in a non-linear hyperbolic Lineweaver-Burk plot.