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1.
Urologe A ; 61(3): 250-259, 2022 Mar.
Article in German | MEDLINE | ID: mdl-35037970

ABSTRACT

IC/BPS is a chronic progressive disorder that is often difficult and unsatisfactory for the person affected and the treating therapist. Treatment should therefore be comprehensive, interdisciplinary, multimodal and take into account the biopsychosocial model. The guideline forms a thread through the diverse diagnostic and therapeutic options and provides extensive background information on the definition, epidemiology and aetiopathogenesis of this rare disease. However, practice and theory/guideline are different. Adaptation to the individual case is therefore necessary and explicitly desired. The guideline should therefore serve as a source of ideas for colleagues to compile their own standards suitable for their practice. On the one hand, therapy approaches that have been tried and tested in everyday clinical practice are passed on. On the other hand, the frequent lack of evidence should also be viewed critically. Further studies, if possible multi-centre, specifically designed for different aspects of IC/BPS would be desirable. Close networking between therapists in private practice and special centres is essential for the best possible treatment of people with IC/BPS. The guideline is intended to show the limits of what can be done in practices and outpatient clinics and to provide guidance on when patients should be referred to a "Centre for Interstitial Cystitis and Pelvic Pain". Overall, the guideline has improved the presence of this rare disease among colleagues. A comprehensive supplement, update and further substantiation with the state of current research is thus desirable.


Subject(s)
Cystitis, Interstitial , Cystitis, Interstitial/diagnosis , Cystitis, Interstitial/therapy , Humans , Pelvic Pain/therapy
2.
Dalton Trans ; 39(19): 4551-8, 2010 May 21.
Article in English | MEDLINE | ID: mdl-20379588

ABSTRACT

The (SiH3)3P hydride is introduced as a practical source for n-doping of group IV semiconductors and as a highly-reactive delivery agent of -(SiH3)2P functionalities in exploratory synthesis. In contrast to earlier methods, the compound is produced here in high purity quantitative yields via a new single-step method based on reactions of SiH3Br and (Me3Sn)3P, circumventing the need for toxic and unstable starting materials. As an initial demonstration of its utility we synthesized monosubstituted Me2M-P(SiH3)2 (M = Al, Ga, In) derivatives of Me3M containing the (SiH3)2P ligand for the first time, in analogy to the known Me2M-P(SiMe3)2 counterparts. A dimeric structure of Me2M-P(SiH3)2 is proposed on the basis of spectroscopic characterizations and quantum chemical simulations. Next, in the context of materials synthesis, the (SiH3)3P compound was used to dope germanium for the first time by building a prototype p(++)Si(100)/i-Ge/n-Ge photodiode structure. The resultant n-type Ge layers contained active carrier concentrations of 3-4 × 10¹9 atoms cm⁻³ as determined by spectroscopic ellipsometry and confirmed by SIMS. Strain analysis using high resolution XRD yielded a Si content of 4 × 10²° atoms cm⁻³ in agreement with SIMS and within the range expected for incorporating Si3P type units into the diamond cubic Ge matrix. Extensive characterizations for structure, morphology and crystallinity indicate that the Si co-dopant plays essentially a passive role and does not compromise the device quality of the host material nor does it fundamentally alter its optical properties.

4.
Phys Rev Lett ; 102(10): 107403, 2009 Mar 13.
Article in English | MEDLINE | ID: mdl-19392159

ABSTRACT

A direct absorption edge tunable between 0.8 and approximately 1.4 eV is demonstrated in strain-free ternary Ge_{1-x-y}Si_{x}Sn_{y} alloys epitaxially grown on Ge-buffered Si. This decoupling of electronic structure and lattice parameter-unprecedented in group-IV alloys-opens up new possibilities in silicon photonics, particularly in the field of photovoltaics. The compositional dependence of the direct band gap in Ge_{1-x-y}Si_{x}Sn_{y} exhibits a nonmonotonic behavior that is explained in terms of coexisting small and giant bowing parameters in the two-dimensional compositional space.

5.
Phys Rev Lett ; 95(26): 266105, 2005 Dec 31.
Article in English | MEDLINE | ID: mdl-16486376

ABSTRACT

Gallium nitride films, epitaxially grown on Si(111) via a lattice-matched ZrB(2) buffer layer by plasma-assisted molecular beam epitaxy, have been studied in situ by noncontact atomic force microscopy and also in real time by reflection high-energy electron diffraction. The grown films were determined to be always N-polar. First-principles theoretical calculations modeling the interface structure between GaN(0001) and ZrB(2)(0001) clarify the origin of the N polarity.

6.
Phys Rev Lett ; 88(20): 206102, 2002 May 20.
Article in English | MEDLINE | ID: mdl-12005580

ABSTRACT

Two compounds SiC and AlN, normally insoluble in each other below approximately 2000 degrees C, are synthesized as a single-phase solid-solution thin film by molecular beam epitaxy at 750 degrees C. The growth of epitaxial SiCAlN films with hexagonal structure takes place on 6H-SiC(0001) substrates. Two structural models for the hexagonal SiCAlN films are constructed based on first-principles total-energy density functional theory calculations, each showing agreement with the experimental microstructures observed in cross-sectional transmission electron microscopy images. The predicted fundamental band gap is 3.2 eV for the stoichiometric SiCAlN film.

7.
Photosynth Res ; 63(2): 145-57, 2000.
Article in English | MEDLINE | ID: mdl-16228425

ABSTRACT

Synechococcus sp. strains PCC 7942 and PCC 6301 contain a 35 kDa protein called IdiA (Iron deficiency induced protein A) that is expressed in elevated amounts under Fe deficiency and to a smaller extent also under Mn deficiency. Absence of this protein was shown to mainly damage Photosystem II. To decide whether IdiA has a function in optimizing and/or protecting preferentially either the donor or acceptor side reaction of Photosystem II, a comparative analysis was performed of Synechococcus sp. PCC 7942 wild-type, the IdiA-free mutant, the previously constructed PsbO-free Synechococcus PCC 7942 mutant and a newly constructed Synechococcus PCC 7942 double mutant lacking both PsbO and IdiA. Measurements of the chlorophyll fluorescence and determinations of Photosystem II activity using a variety of electron acceptors gave evidence that IdiA has its main function in protecting the acceptor side of Photosystem II. Especially, the use of dichlorobenzoquinone, preferentially accepting electrons from Q(A), gave a decreased O(2) evolving activity in the IdiA-free mutant. Investigations of the influence of hydrogen peroxide treatment on cells revealed that this treatment caused a significantly higher damage of Photosystem II in the IdiA-free mutant than in wild-type. These results suggest that although the IdiA protein is not absolutely required for Photosystem II activity in Synechococcus PCC 7942, it does play an important role in protecting the acceptor side against oxidative damage.

8.
J Am Soc Inf Sci ; 36(2): 82-93, 1985 Mar.
Article in English | MEDLINE | ID: mdl-10300015

ABSTRACT

In this article the authors present their analysis of the online search patterns within user searching sessions of the National Library of Medicine ELHILL system and examine the user search patterns on the CATLINE database. In addition to the CATLINE analysis, a comparison is made using data previously analyzed on the MEDLINE database for the same time period, thus offering an opportunity to compare the performance parameters of different databases within the same information system. Data collection covers eight weeks and includes 441,282 transactions and over 11,067 user sessions, which accounted for 1680 hours of system usage. The descriptive analysis contained in this report can assists system design activities, while the predictive power of the transaction log analysis methodology may assists the development of real-time aids.


Subject(s)
Cataloging , MEDLARS/statistics & numerical data , National Library of Medicine (U.S.) , United States
9.
EMBO J ; 1(12): 1579-82, 1982.
Article in English | MEDLINE | ID: mdl-6327281

ABSTRACT

Several sarcoma-inducing viruses encode protein kinases that phosphorylate tyrosine residues. Such enzymatic activities can be detected within the detergent-insoluble matrix of transformed fibroblasts. We have analysed the protein kinase activities in two murine lymphoma cell lines ( MBL2 and LSTRA) induced by Moloney murine leukemia virus (Mo-MuLV). After incubation of the detergent-insoluble matrix of these cells with [gamma-32P]ATP, several alkali-resistant phosphoproteins, including a very heavily labelled 55 000 mol. wt. protein ( p55 ), have been detected in LSTRA, reflecting the activity of a protein kinase specific to this cell line. This protein kinase activity shares some of the distinctive properties of the protein kinases of transforming viruses, i.e., specificity for tyrosine residues, association with membranous and/or cytoskeletal structures, and inhibition by a synthetic peptide derived from the phosphorylation site of pp60src. In view of the absence of a transforming gene in MoMuLV , it is likely that the high level of protein kinase detected in the LSTRA cell line arises from the expression of a cellular gene.


Subject(s)
Cell Transformation, Viral , Leukemia Virus, Murine/genetics , Protein Kinases/biosynthesis , Amino Acids/analysis , Animals , Animals, Newborn , Cell Line , Enzyme Induction , Lymphoma , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Molecular Weight , Phosphoproteins/isolation & purification , Protein-Tyrosine Kinases
10.
Int J Pept Protein Res ; 17(4): 444-53, 1981 Apr.
Article in English | MEDLINE | ID: mdl-7309348

ABSTRACT

The hormone analog 8-L-tryptophan-oxytocin was synthesized in solution by stepwise chain lengthening from the C-terminal residue. Active esters of 9-fluorenylmethyloxycarbonyl (Fmoc)-amino acids were used for the incorporation of individual residues and thereby exposure to the tryptophan-containing intermediates both to acid conditions and to alkylation could be avoided. In a parallel experiment the parent compound, oxytocin, was prepared similarly. The final products were purified by countercurrent distribution. The presence of tyrosine (donor) and tryptophan (acceptor) in the chain was used for the measurement of the average intramolecular Tyr2-Trp8 distance by evaluation of intramolecular resonance energy transfer between their fluorescent side chains. Since the 8-L-tryptophan analog has high affinity for oxytocin receptors, it is reasonable to assume that its conformation is similar to that of the parent molecule and that in the latter the leucine-tyrosine distance is of about the same length. The distance of 13.5 Ao between the side chains of tyrosine and tryptophan measured in aqueous solution is compatible with the Tyr2-Leu8 distance determined with molecular models built according to the proposals of Walter for the biologically active conformation of oxytocin.


Subject(s)
Oxytocin/analogs & derivatives , Amino Acid Sequence , Oxytocin/chemical synthesis , Protein Conformation , Spectrophotometry, Ultraviolet
11.
J Med Chem ; 23(11): 1259-61, 1980 Nov.
Article in English | MEDLINE | ID: mdl-7452679

ABSTRACT

Condensation of (tert-butyloxycarbonyl)tocinoic acid with L-prolyl-L-tryptophylglycinamide produced the Boc derivative of a nonapeptide (disulfide) which on deprotection afforded [8-L-tryptophan]oxytocin. In assays on the rat uterus in vitro and in vivo the new analogue acts as both an agonist and an antagonist. The duration of both actions is prolonged.


Subject(s)
Oxytocin/analogs & derivatives , Animals , Chemical Phenomena , Chemistry , Female , In Vitro Techniques , Oxytocin/chemical synthesis , Oxytocin/pharmacology , Rats , Uterine Contraction/drug effects
12.
Int J Pept Protein Res ; 16(5): 402-11, 1980 Nov.
Article in English | MEDLINE | ID: mdl-6163740

ABSTRACT

The acetyl-derivative of the biologically active C-terminal 7-peptide portion of cholecystokinin (CCK), N-acetyl-O-sulfate-L-tyrosyl-L-methionyl-glycyl-L-tryptophyl-L-methionyl-L-aspartyl-L-phenylalanine amide was prepared by the condensation of 2-peptide segments with 1-isobutyloxycarbonyl-2-isobutyloxy-1,2-dihydroquinoline as coupling reagent. The N-terminal residue, tyrosine was incorporated by the active ester method. The same 7-peptide was prepared also by stepwise chain-lengthening, starting with the C-terminal residue. The 9-fluorenylmethyloxycarbonyl group was applied for the protection of alpha-amino functions. In the release of amylase from acinar cells of the pancreas of guinea pigs, the acetyl-7-peptide amide was about 3 times more potent than CCK 27-33 and equal in potency to CCK 26-33. The new derivative strongly stimulated the contraction of the in situ guinea pig gall bladder.


Subject(s)
Cholecystokinin/analogs & derivatives , Peptide Fragments/chemical synthesis , Sincalide/analogs & derivatives , Amino Acid Sequence , Amylases/metabolism , Animals , Cholecystokinin/chemical synthesis , Cholecystokinin/pharmacology , Gallbladder/drug effects , Guinea Pigs , Muscle Contraction/drug effects , Peptide Fragments/pharmacology
13.
Infect Immun ; 26(2): 458-61, 1979 Nov.
Article in English | MEDLINE | ID: mdl-546782

ABSTRACT

Different methods were used to assay diphtheria toxin sensitivity of fibroblast and heart cell cultures from chicken embryos of various ages. As defined by inhibition of protein synthesis, fibroblasts from 18-day and younger embryos respond more rapidly to toxin than fibroblasts from older embryos. The response of heart cells cultures is independent of the age of the embryos and is similar to the response of fibroblasts from 18-day embryos. Since the EF-2 content is 10-fold less in fibroblasts from 21-day-old embryos, the different responses of protein synthesis to intoxication appear to reside at the membrane level. Cytotoxicity assays in cell culture and in vivo toxin sensitivity assays show that cells from both young and old embryos, as well as whole embryos, are equally sensitive to toxin. Thus, short-term (5-h) measurements of inhibition of protein synthesis are insufficient for determining the relative sensitivity of cells to intoxication as defined by cell death.


Subject(s)
Chick Embryo/drug effects , Diphtheria Toxin/pharmacology , Fibroblasts/drug effects , Animals , Cell Survival/drug effects , Chick Embryo/growth & development , Culture Techniques , Fibroblasts/metabolism , Heart/drug effects , Heart/embryology , Lethal Dose 50 , Muscle Proteins/biosynthesis , Myocardium/cytology , Myocardium/metabolism , Protein Biosynthesis
14.
Int J Pept Protein Res ; 13(1): 22-7, 1979 Jan.
Article in English | MEDLINE | ID: mdl-422321

ABSTRACT

Acylation of the hydroxyl groups in the side chains of serine, threonine or tyrosine occurs in coupling with active esters. This side reaction, which is quite pronounced in histidine-containing peptides, can be prevented with additives. From a series of compounds tested, 2,4-dinitrophenol and pentachlorophenol were the most effective.


Subject(s)
Peptides/chemical synthesis , Acylation , Amino Acid Sequence , Dinitrophenols , Esters , Pentachlorophenol , Serine , Threonine , Tyrosine
15.
Int J Pept Protein Res ; 12(2): 57-68, 1978 Aug.
Article in English | MEDLINE | ID: mdl-711371

ABSTRACT

The acid catalyzed O leads to C migration of the benzyl group in the side chain of tyrosine could be reduced by applying HBr in a mixture of phenol and p-cresol instead of BHr in trifluoroacetic acid for acidolytic deprotection. This side reaction occurs also during the removal of Boc groups. The loss of O-benzyl protection and the formation of 3-benzyltyrosine residues could be suppressed by the application of a 7:3 mixture of trifluoroacetic acid and acetic acid. The acid- and base-catalyzed ring closure of beta-benzylaspartyl residues to aminosuccinyl derivatives was also studied. In this case HBr in trifluoroacetic acid was found to be relatively harmless. Deprotection with HBr in a mixture of trifluoroacetic acid and p-cresol can be applied for peptides that contain both beta-benzylaspartyl and O-benzyltyrosyl residues. An attempt to reduce the rate of the base-catalyzed side reaction by application of hindered tertiary amines was abandoned because the tertiary amines which were effective in this respect let to significant reduction of the rate of the desired reaction, the aminolysis of active esters, as well. A satisfactory solution for the problem was found in the selective catalysis of the active ester reaction with 1-hydroxybenzotriazole or 4-dimethyl-aminopyridine. These catalysts do not enhance the rate of ring closure and in their presence essentially pure beta-benzylaspartyl peptides can be produced in good yield.


Subject(s)
Aspartic Acid , Peptides/chemical synthesis , Tyrosine , Benzyl Compounds , Chemical Phenomena , Chemistry , Methods
16.
Int J Pept Protein Res ; 10(5): 380-4, 1977 Nov.
Article in English | MEDLINE | ID: mdl-604287

ABSTRACT

Acylation of amino acid beta-naphthylamides with protected (Boc) amino acidisobutylcarbonic acid mixed anhydrides resulted in each case in the formation of some undesired by-product: an isobutyloxycarbonylamino acid beta-naphthylamide. The amount of this second acylation product was particularly high, with the hindered amino acids valine and isoleucine as carboxyl-components. The nature of the amino component had no major influence on the extent of this side reaction.


Subject(s)
Peptides/chemical synthesis , Acylation , Amino Acid Sequence , Anhydrides , Chemical Phenomena , Chemistry
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