SH-It happens: S-H bonds as intrinsic 2D-IR labels in proteins.

Cysteine S-H bonds have a spectroscopically convenient stretching frequency of ∼2550 cm-1. However, their cross section is low, and the band can be strongly broadened in heterogeneous environments, making detection very challenging. With two-dimensional infrared (2D-IR) setups achieving ever higher sensitivities in recent years, systematic use of the weak cysteine sulfhydryls (Cys-SHs) absorption band is now within reach, even at low millimolar protein concentrations. Here, we demonstrate the capabilities of Cys-SH as an intrinsic 2D-IR label in pyruvate oxidase from E. coli, an enzyme with ten cysteines in its native sequence. 1D-IR measurements on the wild-type and individual cysteine knock-out variants show that two such residues have especially narrow SH signatures, caused by their intrahelical hydrogen bonding. 2D-IR analysis of these bands reveals an extraordinarily high anharmonicity (∼110 cm-1) and a long vibrational lifetime (∼4 ps). This allows monitoring spectral diffusion via center line slope analysis for up to 10 ps-separately for both the ground and excited states. The unique spectroscopic features and its ease of introduction make Cys-SH a useful IR spectroscopic label.

A multimodal microcharacterisation of trace-element zonation and crystallographic orientation in natural cassiterite by combining cathodoluminescence, EBSD, EPMA and contribution of confocal Raman-in-SEM imaging.

In cassiterite, tin is associated with metals (titanium, niobium, tantalum, indium, tungsten, iron, manganese, mercury). Knowledge of mineral chemistry and trace-element distribution is essential for: the understanding of ore formation, the exploration phase, the feasibility of ore treatment, and disposal/treatment of tailings after the exploitation phase. However, the availability of analytical methods make these characterisations difficult. We present a multitechnical approach to chemical and structural data that includes scanning electron microscopy (SEM)-based imaging and microanalysis techniques such as: secondary and backscattered electrons, cathodoluminescence (CL), electron probe microanalyser (EPMA), electron backscattered diffraction (EBSD) and confocal Raman-imaging integrated in a SEM (RISE). The presented results show the complementarity of the used analytical techniques. SEM, CL, EBSD, EPMA provide information from the interaction of an electron beam with minerals, leading to atomistic information about their composition, whereas RISE, Raman spectroscopy and imaging completes the studies with information about molecular vibrations, which are sensitive to structural modifications of the minerals. The correlation of Raman bands with the presence/absence of Nb, Ta, Fe (heterovalent substitution) and Ti (homovalent substitution) is established at a submicrometric scale. Combination of the different techniques makes it possible to establish a direct link between chemical and crystallographic data of cassiterite.

High-precision background correction and artifact suppression for ultrafast spectroscopy by quasi-simultaneous measurements in a split-sample cell.

Alternating acquisition of background and sample spectra is often employed in conventional Fourier-transform infrared spectroscopy or ultraviolet-visible spectroscopy for accurate background subtraction. For example, for solvent background correction, typically a spectrum of a cuvette with solvent is measured and subtracted from a spectrum of a cuvette with solvent and solute. Ultrafast spectroscopies, though, come with many peculiarities that make the collection of well-matched, subtractable background and sample spectra challenging. Here, we present a demountable split-sample cell in combination with a modified Lissajous scanner to overcome these challenges. It allows for quasi-simultaneous measurements of background and sample spectra, mitigating the effects of drifts of the setup and maintaining the beam and sample geometry when swapping between background and sample measurements. The cell is moving between subsequent laser shots to refresh the excited sample volume. With less than 45 µl of solution for 150 µm optical thickness, sample usage is economical. Cell assembly is a key step and covered in an illustrated protocol.

Incarcerated vermiform appendix in a left-sided inguinal hernia.

We report here of a patient with an incarcerated vermiform appendix occurring in a left-sided indirect inguinal hernia. Occasionally, appendices are found in a hernial sac; however, the finding of an incarcerated vermiform appendix in an inguinal hernia on the left side is very unusual and has only been previously described once. The patient suffering this rare entity underwent appendectomy and repair of the hernia and experienced an uneventful postoperative recovery. The possibility of the presence of a situs inversus, or malrotation, as an underlying cause for the observed pathology was excluded by x-ray examination.

Reversible decrease of collagen crosslinking by protein low diet and aminoacetonitrile--effect of D-penicillamine and prednisolone on the rise of crosslinks.

After ending a 4-week period of low-protein diet with or without aminoacetonitrile (AAN), the tail tendons of rats showed an increase of hydroxylysinonorleucine (HLNL) together with other unidentified reducible crosslinks. The binding of dihydroxylysinonorleucine type (DHLNL) was an exception: its content remained unchanged. It may be, assumed, therefore, that the procedures mentioned above act indiscriminately against all reducible crosslinks with the exception of DHLNL. The rise in crosslinks after the 4-week pretreatment was disturbed, when d-penicillamine was given, because it specifically inhibited the formation of HLNL. The content of other crosslink components was slightly increased above that of controls so that the absolute content of total isolated crosslinks increased in the presence of d-penicillamine. No statistically significant differences could be obtained under prednisolone.

Lateral cervical (branchial) cyst epithelia express upper digestive tract-type cytokeratins. Polyclonal antibody studies.

The epithelial lining of lateral cervical cysts (LCCs) was analyzed for keratin polypeptide composition by means of high resolution gel electrophoresis and immunoblotting using polyclonal rabbit antikeratin antisera of defined specificity. The keratin phenotype expressed in branchial mass epithelia was found to be homologous to the profiles obtained for the squamous epithelium of corresponding palatine tonsils, but was clearly different from related polypeptide complements of both epidermis and simple (columnar) epithelium. The presence of particular keratin members (pairs 5/14 and 4/13) strongly indicates that branchial mass inner lining derives from keratinocytes that are programmed to form a stratified squamous epithelium and reveal, at least biochemically, an upper digestive tract or esophageal type of differentiation. On the basis of these data and the recent finding that a neck lymph node is involved as a target tissue in LCC formation, hypotheses concerning branchial mass histogenesis in general appear to be highly unsettled. We propose an alternative model that may explain the conflicting clinical, anatomic, and morphologic findings associated with LCC disease.

Keratins as molecular markers of epithelial differentiation: differential expression in crypt epithelium of human palatine tonsils.

The expression of keratins in the stratified squamous nonkeratinizing epithelium lining the surface and the crypts of human palatine tonsils was analyzed by high-resolution gel electrophoresis, immunoblotting, and immunohistochemical techniques. In contrast to the superficial epithelium, which showed a fairly constant keratin composition consisting of the neutral-to-basic keratins K4, K5, K6, and K8 and the acidic keratins K13, K14, K16, and K19, the keratin profiles of tonsillar crypt epithelial cells were found to be more variable, particularly with respect to the expression levels of K4 and K13. These were identical to those of surface epithelium, reduced, or abolished. Since K4 and K13 characterize the mature stage of differentiation in squamous nonkeratinizing epithelia, their decrease is indicative of an incomplete epithelial differentiation. Immunohistochemical analyses confirmed this hypothesis and allowed us, furthermore, to correlate the expression of K13 with the morphologic alterations of tonsillar crypt epithelium in the course of reticulation.

Characterization of alunite supergroup minerals by Raman spectroscopy.

Raman spectroscopy has been used to study the molecular structure of different natural minerals of the alunite supergroup (AB(3)(XO(4))(2)(OH)(6)), with A=K(+), Na(+), Ca(2+), Sr(2+), Ba(2+), B=Al(3+), Fe(3+) and X=S(6+), P(5+). The influence of the ions, in A-, B- and X-sites, is highlighted in the Raman spectra by variations in the position of certain vibrations and is discussed in association with published crystallographic data in order to describe the observed differences. It was found that A-site substitutions are characterized by wavenumber shifts of the vibrations involving hydroxyl groups. The positions of these vibrational bands vary linearly with the ionic radius of the ions in this site. B-site substitutions induce shifts of all bands due to structural modifications that lead to differences in the chemical environment around the hydroxyl and XO(4) groups and changes in B-O bond lengths. A correlation showed that these shifts correlate well with the ionic radii of the B-ions. The spectra of compounds containing both sulfate and phosphate groups are described by numerous vibration bands caused by a complex elemental composition and a symmetry change of the XO(4) groups. This study has also made it possible to generalize substitution effects on the wavenumbers of several vibrations and show that Raman spectroscopy could be a powerful tool for identifying and distinguishing minerals of the alunite supergroup.

Functional recovery after ischemic stroke--a matter of age: data from the Austrian Stroke Unit Registry.

OBJECTIVE: To analyze the association between patient age and good functional outcome after ischemic stroke with special focus on young patients who were numerically underrepresented in previous evaluations. METHODS: Of 43,163 ischemic stroke patients prospectively enrolled in the Austrian Stroke Unit Registry, 6,084 (14.1%) were ≤55 years old. Functional outcome was available in a representative subsample of 14,256 patients free of prestroke disability, 2,223 of whom were 55 years or younger. Herein we analyzed the effects of age on good functional outcome 3 months after stroke (modified Rankin Scale score ≤2). RESULTS: Good outcome was achieved in 88.2% (unadjusted probability) of young stroke patients (≤55 years). In multivariable analysis, age emerged as a significant predictor of outcome independent of stroke severity, etiology, performance of thrombolysis, sex, risk factors, and stroke complications. When the age stratum 56-65 years was used as a reference, odds ratios (95% confidence interval [95% CI]) of good outcome were 3.4 (1.9-6.4), 2.2 (1.6-3.2), and 1.5 (1.2-1.9) for patients aged 18-35, 36-45, and 46-55 years and 0.70 (0.60-0.81), 0.32 (0.28-0.37), and 0.18 (0.14-0.22) for those aged 66-75, 76-85, and >85 years (p < 0.001). In absolute terms, the regression-adjusted probability of good outcome was highest in the age group 18-35 years and gradually declined by 3.1%-4.2% per decade until age 75 with a steep drop thereafter. Findings applied equally to sexes and patients with and without IV thrombolysis or diabetes. CONCLUSIONS: Age emerged as a highly significant inverse predictor of good functional outcome after ischemic stroke independent of stroke severity, characteristics, and complications with the age-outcome association exhibiting a nonlinear scale and extending to young stroke patients.

Recanalization after thrombolysis in stroke patients: predictors and prognostic implications.

OBJECTIVE: To estimate rates, predictors, and prognostic importance of recanalization in an unselected series of patients with stroke treated with IV thrombolysis. METHODS: We performed a CT angiography or transcranial Doppler (TCD) follow-up examination 24 hours after IV thrombolysis in 64 patients with documented occlusion of the intracranial internal carotid or middle cerebral artery (MCA). Complete recanalization was defined by a rating of 3 on the Thrombolysis in Myocardial Infarction or 4/5 on the Thrombolysis in Brain Ischemia grading scales. Information about risk factors, clinical features, and outcome was prospectively collected by standardized procedures. RESULTS: Complete recanalization was achieved in 36 of the 64 patients (56.3%). There was a nonsignificant trend of recanalization rates to decline with a more proximal site of occlusion: 68.4% (M2 segment of MCA), 53.1% (M1 segment), and 46.2% (carotid T) (p for trend = 0.28). Frequencies of vessel reopening were markedly reduced in subjects with diabetes (9.1% vs 66.0% in nondiabetics, p < 0.001) and less so in subjects with additional extracranial carotid occlusion (p = 0.03). Finally, complete recanalization predicted a favorable stroke outcome at day 90 independently of the information provided by age, NIH Stroke Scale, and onset-to-needle time. CONCLUSIONS: We found a high rate of vessel recanalization after IV thrombolysis occlusion. However, recanalization was infrequent in patients with diabetes and extracranial carotid occlusion. Information on recanalization was a powerful, early predictor for clinical outcome.

[Medical rehabilitation of disability insurance--determination of the status and future perspectives]. / Medizinische Rehabilitation der Rentenversicherung--Standortbestimmung und Zukunftsperspektiven.

The legal prerequisites for medical rehabilitation offered by the pension insurance institutions are described. The definition of position includes the attitude towards applying for rehabilitation and its repercussions on the selection of rehabilitation, specific questions with regard to expert opinion, the indications for general medical rehabilitation measures and the changes within the concept of rehabilitation. Future possibilities are shown. Some examples of rehabilitation measures relating to specific indications are chosen to demonstrate successes and problems in this regard. Finally, the present state of research in rehabilitation and its future development are considered.

[Ascertainment of physical fitness for work in persons applying for annuities in the Federal Republic of Germany (author's transl)]. / Feststellung der Leistungsfähigkeit im Erwerbsleben beim Rentenantragsverfahren in der Bundesrepublik Deutschland.

Annuities granted because of unfitness for work in general or unfitness to perform particular professional work are being paid in Germany by a state insurance agency. Unfitness for work has to be ascertained in each individual case as has been ruled by jurisdiction of the Highest German Court. It is the task of the medical expert in the course of this procedure to register the clinical status of the applicants and to reach a medical judgment in regard to fitness for work. This judgment does not rely upon the diagnosis or prognosis of a particular disease; a decreased fitness for work because of a particular disease can only be assumed if the disease has led to long-term irreversible deficient organ functions. Annuities for a limited time period may be granted if there is a chance for improvement of health. Problems of finding expert judgement are reported.

Allele frequencies and segregation of human polymorphic keratins K4 and K5.

Two electrophoretic variants for each of the human keratins K4 and K5 that are expressed in squamous nonkeratinizing epithelia lining the upper digestive tract could be distinguished on SDS-PAGE. Based on a sampling size of 1,299 unrelated individuals, calculation of allele frequencies showed the alleles to be in Hardy-Weinberg equilibrium. The genetic basis of this variation was confirmed by both quantitative gene dosage dependence and the transmission of the variants as Mendelian traits in two families. Thus the human keratin genes K4 and K5 are polymorphic, and each presents with two codominant alleles (a and b).

[The influence of chronic exposure to lead on the formation of lung metastases in a syngeneic system (author's transl)]. / Der Einfluss einer chronischen Bleibelastung auf die Entwicklung von Lungenmetastasen in einem syngenetischen System.

Mice of strain A/J were fed for a period of 13 weeks with pellets containing lead-acetate either 300 mg/kg or 3000 mg/kg (Altromin 1314). Then the animals were injected i.v. with 500 000 of living YAC tumor cells. Nine days later the mice were killed by neck dislocation, the lung metastases were visualized by ink injection into the trachea, and the total metastatic size per lung was expressed as the square area of all metastases. Animals in both leadtreated groups showed highly significant reduction of metastatic formation in comparison with the untreated control group. This effect was even stronger expressed in the group with higher dose of lead. Various mechanisms are discussed, especially the influence of lead on immune mechanisms.

Synthesis of oligonucleotides with sequences identical with or analogous to the 3'-end of 16S ribosomal RNA of Escherichia coli: preparation of m-6-2-A-C-C-U-C-C and A-C-C-U-C-m-4-2C via phosphotriester intermediates.

The synthesis of two fully-protected hexanucleotides (11a and 11b) via a phosphotriester approach, which is based on the use of two types of protecting groups for the internucleotide linkages, i.e. one 2,2,2-tribromo-ethyl at the 5'-terminus and four 2-chlorophenyl groups for the remaining linkages, is reported. The hexanucleotides 11a and 11b, assembled via a block-wise two-step phosphotriester method, can be deblocked conveniently to give the two hexamers 12a and 12b containing only 3'leads to5' internucleotide linkages.

Conformational analysis of a ribopentanucleoside tetraphosphate in aqueous solution. A two-dimensional NMR study at 500 MHz.

The 30 ribose proton resonances of the pentaribonucleoside tetraphosphate m6(2)AUm6(2)AUm6(2)A have been assigned unequivocally by means of spin-echo-correlated spectroscopy, 2D J-resolved spectroscopy and Nuclear Overhauser difference spectroscopy, carried out at 500 MHz. A detailed comparison of the conformational properties of the title compound with its constituent fragments m6(2)AUm6(2)AU, m6(2)AUm6(2)A, m6(2)AU and the relevant monomers is given. Chemical shift data indicate the existence of a doubly "bulged out" conformer, in which the two interior U-fragments are not involved in regular nearest neighbour stacking interactions. The coupling constants of the ribose-ring are interpreted in terms of the N/S equilibrium, and population distributions along the backbone angles beta and gamma are presented. The combined data suggest a strong similarity between the 5'-terminal triplets in m6(2)AUm6(2)AUm6(2)A, m6(2)AUm6(2)AU and m6(2)AUm6(2)A2.

Chemical synthesis of a messenger ribonucleic acid fragment: AUGUUCUUCUUCUUCUUC.

The synthesis via a phosphotriester method of the octadecaribonucleotide AUG(UUC)5 (19) is reported. The octadecanucleotide is meant to serve as a synthetic messenger in a ribosomal protein synthesizing system. A fully protected octadecamer intermediate (18a) was prepared by a block coupling procedure. For the introduction of the desired 3'-5'-internucleotide bonds a 3'-O-(2,2,2-trichloroethyl 2-chlorophenyl phosphate) function was incorporated into the monomeric building blocks which were applied in the synthesis of 18a. Monomeric and oligomeric compounds with a thus protected 3'-O-phosphotriester function can be selectively deblocked to give 3'-O-phosphodiester derivatives suitable for condensation with 5'-hydroxyl (oligo)nucleotides. Conversion of fully protected oligomers to 5'-hydroxyl derivatives, suitable for further coupling at the 5' end, was effected by selective removal of the levulinyl function at the 5' end. The fully protected octadecanucleotide 18a was deblocked with fluoride ions, followed by ammonia and acid to give the required octadecamer 19. The condensing agent 1-(2,4,6-triisopropyl-phenylsulfonyl)-3-nitro-1,2,4-triazole, which was applied to effect the formation of fully protected 3'-5'-internucleotide phosphotriester functions, may give rise to side reactions with the heterocylic bases uracil and guanine. The consequences of these side reactions for the synthesis of octadecamer 19 are reported.

Synthesis of fluorochromes and pigments in Malassezia furfur by use of tryptophan as the single nitrogen source.

A new minimal medium consisting only of L-tryptophan (L-Trp) and a lipid source induced formation of brown pigmentation only in the species Malassezia furfur, which diffuses into the agar. Strains of the species M. sympodialis and M. pachydermatis failed to grow on this medium. On mDixon medium, however, after replacement of peptone by L-Trp, growth of all three Malassezia species was achieved. Under these conditions pigment production was observed with all M. furfur strains tested, although the results for M. pachydermatis strains were inconsistent. M. sympodialis strains showed no pigment production. On the minimal medium pigmentogenesis was induced in M. furfur by only 0.01 g% tryptophan; the pH optimum was pH 5. In all M. furfur strains, alternative amino nitrogen sources given concurrently with Trp suppressed pigmentogenesis. Furthermore, there were differences in the optimal temperature among the individual M. furfur strains. CBS 7019, CBS 6000 and CBS 6001 failed to produce pigment at 37 degrees C. The extract of the culture exhibited remarkable fluorescence, and several indole derivatives with a broad spectrum of colours were detected. This finding may have an impact on the clinical appearance of pityriasis versicolor, a very common skin disease caused by lipophilic yeasts of the genus Malassezia. We hypothesize that in pityriasis versicolor metabolic adaptation of Malassezia yeasts to altered nitrogen conditions on superficial skin might be of patho-physiological importance. Tryptophan as an inducer of pigmentogenesis probably accumulates during excessive sweating, a well-known manifestation of pityriasis versicolor.

[Synthesis of fluorochromes and pigments in Malassezia furfur by using tryptophan as the single source of nitrogen]. / Synthese von Fluorochromen und Pigmenten durch Malassezia furfur unter Verwendung von Trypthophan als alleiniger Stickstoffquelle.

A new minimal medium consisting only of L-tryptophan (L-trp) and a lipid source induced formation of brown pigmentation only in the species Malassezia furfur. Strains of the species M. sympodialis and M. pachydermatis failed to grow on this medium. Pigmentogenesis was already induced in M. furfur by 0.01 g% tryptophan, the pH optimum was pH = 5. Alternative amino nitrogen sources given concurrently with trp suppressed pigmentogenesis. The extract of the culture exhibited remarkable fluorescence, and several indole derivatives with a broad spectrum of colors were detected by means of mass spectroscopy and NMR. This finding may have an impact on the clinical appearance of pityriasis versicolor, a very common skin disease caused by lipophilic yeasts of the genus Malassezia. We hypothesize that in pityriasis versicolor metabolic adaptation of Malassezia yeasts to altered nitrogen conditions on superficial skin might be of pathophysiological importance. Tryptophan as inductor of pigmentogenesis probably cumulates during excessive sweating, a well known manifestation factor of pityriasis versicolor.