High-power continuous-wave mid-infrared radiation generated by difference frequency mixing of diode-laser-seeded fiber amplifiers and its application to dual-beam spectroscopy

We report the generation of up to 0.7 mW of narrow-linewidth (<60-MHz) radiation at 3.3 micrometers by difference frequency mixing of a Nd:YAG-seeded 1.6-W Yb fiber amplifier and a 1.5-micrometers diode-laser-seeded 0.6-W Er/Yb fiber amplifier in periodically poled LiNbO3. A conversion efficiency of 0.09%/W (0.47 mWW-2 cm-1) was achieved. A room-air CH4 spectrum acquired with a compact 80-m multipass cell and a dual-beam spectroscopic configuration indicates an absorption sensitivity of +/-2.8 x 10(-5) (+/-1 sigma), corresponding to a sub-parts-in-10(9) (ppb) CH4 sensitivity (0.8 ppb).

Somatostatin receptor interacting protein defines a novel family of multidomain proteins present in human and rodent brain

By using the yeast two-hybrid system we identified a novel protein from the human brain interacting with the C terminus of somatostatin receptor subtype 2. This protein termed somatostatin receptor interacting protein is characterized by a novel domain structure, consisting of six N-terminal ankyrin repeats followed by SH3 and PDZ domains, several proline-rich regions, and a C-terminal sterile alpha motif. It consists of 2185 amino acid residues encoded by a 9-kilobase pair mRNA; several splice variants have been detected in human and rat cDNA libraries. Sequence comparison suggests that the novel multidomain protein, together with cortactin-binding protein, forms a family of cytoskeletal anchoring proteins. Fractionation of rat brain membranes indicated that somatostatin receptor interacting protein is enriched in the postsynaptic density fraction. The interaction of somatostatin receptor subtype 2 with its interacting protein was verified by overlay assays and coimmunoprecipitation experiments from transfected human embryonic kidney cells. Somatostatin receptor subtype 2 and the interacting protein display a striking overlap of their expression patterns in the rat brain. Interestingly, in the hippocampus the mRNA for somatostatin receptor interacting protein was not confined to the cell bodies but was also observed in the molecular layer, suggesting a dendritic localization of this mRNA.

Portable fiber-coupled diode-laser-based sensor for multiple trace gas detection

Tunable narrowband mid-infrared radiation from 3.25 to 4.4 micrometers is generated by a compact fiber-coupled, difference-frequency-based spectroscopic source. A 20-mW external cavity diode laser (with a tuning range from 814 to 870 nm) and a 50-mW distributed-Bragg-reflector diode-laser-seeded ytterbium-doped fiber amplifier operating at 1083 nm are difference-frequency mixed in a multi-grating, temperature-controlled periodically poled LiNbO3 crystal. A conversion efficiency of 0.44 mW/(W2cm) (corresponding to a power of approximately equal to 3 microW at 3.3 micrometers) represents the highest conversion efficiency reported for a portable device. Performance characteristics of such a sensor and its application to spectroscopic detection of CO2, N2O, H2CO, HCl, NO2, and CH4 will be reported in this work.

Reverse physiology in drosophila: identification of a novel allatostatin-like neuropeptide and its cognate receptor structurally related to the mammalian somatostatin/galanin/opioid receptor family

By using degenerate oligonucleotide primers deduced from the conserved regions of the mammalian somatostatin receptors, a novel G-protein-coupled receptor from Drosophila melanogaster has been isolated exhibiting structural similarities to mammalian somatostatin/galanin/opioid receptors. To identify the bioactive ligand, a 'reverse physiology' strategy was used whereby orphan Drosophila receptor-expressing frog oocytes were screened against potential ligands. Agonistic activity was electrophysiologically recorded as inward potassium currents mediated through co-expressed G-protein-gated inwardly rectifying potassium channels (GIRK). Using this approach a novel peptide was purified from Drosophila head extracts. Mass spectrometry revealed an octapeptide of 925 Da with a sequence Ser-Arg-Pro-Tyr-Ser-Phe-Gly-Leu-NH(2) reminiscent of insect allatostatin peptides known to control diverse functions such as juvenile hormone synthesis during metamorphosis or visceral muscle contractions. Picomolar concentrations of the synthesized octapeptide activated the cognate receptor response mediated through GIRK1, indicating that we have isolated the 394-amino-acid Drosophila allatostatin receptor which is coupled to the Gi/Go class of G proteins.

Identification of a cis-acting dendritic targeting element in MAP2 mRNAs

In neurons, a limited number of mRNAs have been identified in dendritic processes, whereas other transcripts are restricted to the cell soma. Here we have investigated the molecular mechanisms underlying extrasomatic localization of mRNAs encoding microtubule-associated protein 2 (MAP2) in primary neuronal cultures. Vectors expressing recombinant mRNAs were introduced into hippocampal and sympathetic neurons using DNA transfection and microinjection protocols, respectively. Chimeric mRNAs containing the entire 3' untranslated region of MAP2 transcripts fused to a nondendritic reporter mRNA are detected in dendrites. In contrast, RNAs containing MAP2 coding and 5' untranslated regions or tubulin sequences are restricted to the cell soma. Moreover, 640 nucleotides from the MAP2 3' untranslated region (UTR) are both sufficient and essential for extrasomatic localization of chimeric mRNAs in hippocampal and sympathetic neurons. Thus, a cis-acting dendritic targeting element that is effective in two distinct neuronal cell types is contained in the 3' UTR of MAP2 transcripts. The observation of RNA granules in dendrites implies that extrasomatic transcripts seem to assemble into multimolecular complexes that may function as transport units.

[Pediatric forearm fractures: indications, technique, and limits of conservative management]

Although several "minimal invasive" techniques for the operative management of pediatric forearm fractures have been developed recently, conservative treatment still remains the option with the lowest risk for small patients. We present the results of our clinical and radiological follow-up after an average of 52.4 months (4-112) in 102 pediatric patients. All fractures were treated conservatively. There were 68 fractures (66.7 %) of the distal third of the forearm, 30 fractures (29.4 %) of the midshaft area, and four fractures (3.9 %) in the proximal third of the shaft. Greenstick fractures were seen in 58 cases (56.8 %), complete fractures with displacement of both corticalices in 26 patients (25.5 %), and folding fractures in 18 cases (17.7 %). With the exception of one fracture with the necessity of remanipulation after redisplacement in the cast, all fractures healed uneventfully without any further intervention. Functional results were excellent with a free range of motion of the wrist and elbow and without any signs of muscular atrophy in 96 children (94.1 %) at the time of follow-up. Six patients, however, showed a significant loss of forearm rotation of an average of 25 degrees (15 degrees -50 degrees ). In four of these six patients, the fracture had been situated in the proximal and midshaft area. Thus, two out of four fractures of the proximal forearm (50.0 %) showed a poor functional outcome. On the basis of our data we recommend conservative management for (closed) pediatric fractures of the distal and midshaft area. Operative treatment is indicated in forearm fractures close to the elbow.

Identification of melanin concentrating hormone (MCH) as the natural ligand for the orphan somatostatin-like receptor 1 (SLC-1)

To identify possible ligands of the orphan somatostatin-like receptor 1 (SLC-1), rat brain extracts were analyzed by using the functional expression system of Xenopus oocytes injected with cRNAs encoding SLC-1 and G protein-gated inwardly rectifying potassium channels (GIRK). A strong inward current was observed with crude rat brain extracts which upon further purification by cation exchange chromatography and high performance liquid chromatography (HPLC) yielded two peptides with a high agonist activity. Mass spectrometry and partial peptide sequencing revealed that one peptide is identical with the neuropeptide melanin concentrating hormone (MCH), the other represents a truncated version of MCH lacking the three N-terminal amino acid residues. Xenopus oocytes expressing the MCH receptor responded to nM concentrations of synthetic MCH not only by the activation of GIRK-mediated currents but also by the induction of Ca(2+) dependent chloride currents mediated by phospholipase C. This indicates that the MCH receptor can couple either to the G(i)- or G(q)-mediated signal transduction pathway, suggesting that MCH may serve for a number of distinct brain functions including food uptake behavior.

Brillouin and Umklapp scattering in polybutadiene: comparison of neutron and x-ray scattering

We report a comparison of high resolution inelastic x-ray Brillouin scattering to coherent inelastic neutron scattering for amorphous deuterated polybutadiene, done for one temperature in the glass phase and another one in the melt. The x-ray scattering proves to be by far the better technique for such a polymer within its present resolution bounds. The neutron scattering allows one to extend these measurements to a much better resolution, showing an additional quasielastic signal in the melt. The results suggest x-ray measurements at higher momentum transfer, to see whether they are complementary to neutrons.

Prolonged adjustment difficulties among those with acute posttrauma distress following burn injury

This study examined the impact of mild to moderate symptoms of in-hospital posttrauma distress (PTD) following severe burn injury on quality of life (QOL) at 2-month follow-up after controlling for preburn QOL, injury severity, and state Negative Affectivity (depression, body image dissatisfaction) and dispositional optimism-pessimism. Participants' (n = 86) self-report established PTD and non-PTD groups (median split on Davidson Trauma Scale). After covarying preburn level of psychosocial QOL, PTD groups differed on psychosocial functioning at follow-up. This effect remained after covarying injury severity, state NA, dispositional optimism-pessimism, and preburn Mental domain QOL. PTD groups also differed significantly on physical functioning at follow-up after covarying preburn physical functional status. This effect was removed by controlling preburn Physical domain QOL and either injury severity or state NA and dispositional optimism-pessimism. Therefore, PTD is related to significant impairments in the physical and psychosocial adjustment of survivors of severe burns regardless of pretrauma level of adjustment. Injury severity and state NA and dispositional optimism-pessimism moderate the impact of PTD on physical but not psychosocial adjustment.

Effects of ischemia on QT dispersion during spontaneous anginal episodes

Myocardial ischemia induced by pacing, angioplasty, or stress results in a significant increase in QT dispersion (QTd = QT maximum - QT minimum). This study investigated the effects of ischemia on QTd and the rate-corrected QTd (QT(c)d) during spontaneous anginal episodes in patients with coronary artery disease (CAD). Ninety-five patients with CAD and typical angina pectoris and 15 control subjects complaining of anginalike symptoms were studied. QTd and QT(c)d were calculated from 12-lead surface electrocardiograms recorded during and after the relief of pain. QTd and QT(c)d were significantly higher during the anginal episode (84+/-31 ms and 98+/-51 ms) compared to the painless conditions (69+/-24 ms and 71+/-24 ms) (P = .003 and P = .001 for QTd and QT(c)d, respectively) only in the 57 CAD patients who had a history of an old previous myocardial infarction. QTd and QT(c)d are significantly increased during spontaneous angina in patients with documented CAD and history of previous myocardial infarction.

Agonist-dependent interaction of the rat somatostatin receptor subtype 2 with cortactin-binding protein 1

We report here an interaction between the C terminus of the rat somatostatin receptor subtype 2 (SSTR2) and a protein that has recently been identified as cortactin-binding protein 1 (CortBP1). Interaction is mediated by the PDZ (PSD-95/discs large/ZO-1) domain of CortBP1. As shown by in situ hybridization, SSTR2 and cortactin-binding protein are coexpressed in the rat brain. The association between SSTR2 and the PDZ-domain of CortBP1 was verified by overlay assays and by coprecipitation after transfection in human embryonic kidney (HEK) cells. Analysis by confocal microscopy indicates that CortBP1 is distributed diffusely throughout the cytosol in transfected cells and that it becomes concentrated at the plasma membrane when SSTR2 is present. This process is largely increased when the receptor is stimulated by somatostatin; as CortBP1 interacts with the C terminus of SSTR2, our data suggest that the binding of agonist to the receptor increase the accessibility of the receptor C terminus to the PDZ domain of CortBP1. Our data for the first time establish a link between a G-protein coupled receptor and constituents of the cytoskeleton.

[Minimally invasive therapeutic concepts in fracture surgery]

Recent publications show a clear tendency towards minimally invasive procedures for fracture care in trauma patients. Intramedullary stabilization has become the first choice in reconstructing axis and length of the diaphyseal fractures of the long bones. Indications for intramedullary nailing have become wider with the development of unreamed or retrograde nailing. Essential modifications of plate osteosynthesis from limited contact implants to percutaneous plating and the development of an internal fixator have made this procedure minimally-invasive as well. Techniques of closed reduction and percutaneous osteosynthesis or arthroscopically-assisted procedures have become more important in the stabilization of metaphyseal fractures. Although long term results of some of the mentioned procedures are unknown by now, minimally-invasive techniques appear to have positive influence on functional outcome in most patients. However problems of intraoperative control of axis and rotation in long-bone fractures as well as the surgeon's high exposure to radiation remain unsolved problems in minimally-invasive traumatology.

[How significant is the comparison for length of stay in psychiatric hospitals based on diagnosis and age?]

AIM OF THE STUDY

According to German Hospital Financing Regulations hospital comparisons are undertaken to serve as information basis to providers and purchasers concerning budget findings. The current purchasers' hospital comparison includes diagnosis and patients' age to compare costs between hospitals. This study aims at evaluating diagnosis, age and additional variables as predictors of length of stay for psychiatric inpatient treatment.

METHODS

Data of one year's admissions of a German state psychiatric hospital (N = 2450) were evaluated by a linear regression analysis.

RESULTS

The purchasers' model of diagnosis and age accounts for 10.5% of the variation of length of stay. A second model with additional sociodemographic and clinical variables accounts only for 11.3% of the variation.

CONCLUSIONS

Results of this study are confirmed by several international studies on length of stay in psychiatric hospitals. It is concluded that diagnosis and age do not account sufficiently for the variation of length of stay in psychiatry. Meaningful hospital comparisons should include disease specific clinical, biographical and sociodemographic measures.

Agonist-independent internalization and activity of a C-terminally truncated somatostatin receptor subtype 2 (delta349)

The rat somatostatin receptor subtype 2 (SSTR2) is rapidly internalized and phosphorylated in the presence of somatostatin 14 (SST14). Several C-terminal deletion constructs of SSTR2 have been investigated for their ability to undergo agonist-dependent internalization by using biochemical ligand binding assays and confocal microscopic analysis. Whereas mutant receptors lacking either 10 (delta359), 30 (delta339), or 44 (delta325) amino acid residues at the C terminus required SST14 for internalization, a construct lacking the last 20 amino acids (delta349) was detected mostly intracellularly and independently of the presence of the agonist. When internalization was blocked by sucrose, the delta349 receptor remained at the cell surface, strongly indicating that this mutant is internalized in an agonist-independent fashion. An increased affinity for agonists as measured in membrane binding assays and a reduced level of forskolin-stimulated cyclic AMP accumulation in human embryonic kidney cells expressing delta349 are properties that are characteristic of agonist-independent receptor activity. Delta349 is not phosphorylated detectably in the absence of agonist, demonstrating that phosphorylation per se is not a prerequisite for internalization of SSTR2. This observation is in line with data obtained for the delta325 mutant, which was internalized in an agonist-dependent manner, but not phosphorylated in either the presence or absence of SST14. We conclude that truncation of the SSTR2 C terminus at position 349 leads to agonist-independent, constitutive activity and internalization.

[Elastic intramedullary nailing--a concept for treatment of unstable forearm fracture in childhood]

The standard treatment in forearm fractures of children is usually conservative. Unstable fractures of the proximal parts of the forearm often show poor results after nonoperative management, requiring surgical intervention. We report on 30 children from 4 to 14 years of age who were treated by elastic intramedullary nailing. Sixteen patients were treated by intramedullary pinning immediately after the accident; 14 required intramedullary nailing after failure of the conservative treatment and fracture redislocations. At the time of follow-up 6 months later, functional results were "excellent" in 24 children, "good" in 5 and "fair" in one child. There were no serious complications apart from the occurrence of one delayed union. According to these results intramedullary nailing can be recommended for the treatment of unstable fractures of the proximal and middle parts of the forearm in children.