Combining crystallography and EPR: crystal and solution structures of the multidomain cochaperone DnaJ

Hsp70 chaperones assist in a large variety of protein-folding processes in the cell. Crucial for these activities is the regulation of Hsp70 by Hsp40 cochaperones. DnaJ, the bacterial homologue of Hsp40, stimulates ATP hydrolysis by DnaK (Hsp70) and thus mediates capture of substrate protein, but is also known to possess chaperone activity of its own. The first structure of a complete functional dimeric DnaJ was determined and the mobility of its individual domains in solution was investigated. Crystal structures of the complete molecular cochaperone DnaJ from Thermus thermophilus comprising the J, GF and C-terminal domains and of the J and GF domains alone showed an ordered GF domain interacting with the J domain. Structure-based EPR spin-labelling studies as well as cross-linking results showed the existence of multiple states of DnaJ in solution with different arrangements of the various domains, which has implications for the function of DnaJ.

Wavelength-tunable, sub-picosecond pulses from a passively Q-switched microchip laser system

We present a novel concept to generate sub-picosecond pulses from a passively Q-switched Nd:YVO4 microchip laser system with an adjustable wavelength shift up to a few tens of nanometers around the original emission wavelength of 1064 nm. This concept comprises two stages: one that carries out a nonlinear compression of fiber-amplified microchip pulses and a subsequent stage in which the compressed pulses are coupled into a further waveguide structure followed by a bandpass filter. In a proof-of-principle experiment, pedestal-free 0.62 ps long pulses have been demonstrated with a wavelength shift to 1045 nm.

Ist eine Höhenrekonstruktion mit vergleichsweise wenig Zement für die Radiofrequenz-Kyphoplastie über einen monopedikulären Zugang möglich?

Hintergrund: Perkutane Zementaugmentationssysteme haben sich in den letzten 10 Jahren als eine effektive Behandlungsmethode bei Kompressionsfrakturen durchgesetzt. Als Sonderform ist nun seit 2009 die Radiofrequenz-Kyphoplastie (RF) hinzugekommen, die durch applizierbare Energie die Viskosität des Zements erhöht. Ziel dieser Studie war es, herauszufinden, ob mit einer vergleichsweise geringen Zementmenge eine Wirbelkörpererhöhung für osteoporotische Wirbelkörperfrakturen bei der RF-Kyphoplastie zu erreichen ist. Material und Methode: Bei diesem minimalinvasiven Verfahren wurde das „StabiliT® Vertebral Augmentation System“ der Firma DFine verwendet. Im Rahmen einer retrospektiven Studie wurden von 2011 bis Januar 2012 insgesamt 35 Patienten mit 49 osteoporotischen Wirbelkörperfrakturen versorgt. Als Parameter wurden die Altersstruktur mit Geschlechtsverteilung sowie klinisch der Verlauf der Schmerzintensität anhand der visuellen Analogskala (VAS0–100) ausgewertet. Radiologisch wurde die Wirbelkörpererhöhung (Vorder-, Hinterkante, mittlere Wirbelkörperhöhe und Kyphosewinkel) erfasst und mit dem applizierten Zementvolumen verglichen. Ergebnisse: Alle Patienten hatten vor der Operation eine gescheiterte konservative Behandlung mit weiterhin bestehenden Schmerzen auf Höhe des frakturierten Wirbelkörpers. Bis zur operativen Versorgung vergingen durchschnittlich 3,0 ± 1,3 Wochen. Die durchschnittliche VAS reduzierte sich signifikant von 71 ± 9,2 präoperativ auf 35 ± 6,2 postoperativ (p < 0,001) und nach 3 Monaten weiter auf 30 ± 5,7 (p < 0,001). Mit einem durchschnittlichen Zementvolumen von 2,9 ± 0,7 ml (1,8–4,1) im Thoralbereich und einem durchschnittlichen Zementvolumen von 3,0 ± 0,7 ml (2,0–5,0) im Lumbalbereich wurde eine statistisch signifikante Wirbelkörperaufrichtung erreicht. Die Vorderkante und die mittlere Wirbelkörperhöhe wurden signifikant um 2,3 mm und 3,1 mm angehoben, der Kyphosewinkel reduzierte sich ebenfalls signifikant um 2,1° nach 3 Monaten. Bei 2 Wirbelkörpern (4,1 %) zeigte sich ein minimaler Zementaustritt in die angrenzende Bandscheibe ohne klinische Konsequenz. Bei 2 Patienten entwickelten sich Anschlussfrakturen im kranialen Segment, die erneut mit einer RF-Kyphoplastie behandelt wurden. Schlussfolgerung: Mit einem durchschnittlichen Zementvolumen von 3 ml konnte mit der RF-Kyphoplastie eine schnelle und kurzfristige Besserung der Schmerzsymptomatik erreicht werden. Zusätzlich konnte mit diesem geringen Zementvolumen eine signifikante Wirbelkörperaufrichtung erzeugt werden. Es zeigte sich keine Korrelation zwischen der Wirbelkörperaufrichtung und dem klinischen Ergebnis. Mit der ermittelten Zementleckagenrate von 4,1 % gehört die Radiofrequenz-Kyphoplastie zu den sicheren und effektiven minimalinvasiven perkutanen Zementaugmentationsverfahren. Unsere Daten bestätigen die in der Literatur angegebene höhere Sicherheit für die Kyphoplastie im Vergleich zur Vertebroplastie.

Playing-related musculoskeletal disorders in music students-associated musculoskeletal signs

BACKGROUND

Pain and overuse are common problems for musicians. Up to 80% of professional musicians suffer from playing-related musculoskeletal disorders (PRMD). The prevalence rate in music students is very high as well. Sufficient data on the underlying musculoskeletal dysfunctions however is scarce. Additionally, the self-assessment of health in musicians seems to differ compared to non-musicians, which might influence their attitudes concerning preventive strategies.

AIM

Evaluation of frequency of PRMD in music students, investigation of signs and symptoms in music students compared to non-music controls, comparison of self-reported health and well-being between the two groups.

DESIGN

Prospective, cross-sectional, case control, non-randomized.

SETTING

Other (University volunteers).

POPULATION

Music students in comparison to a non-music control group.

METHOD

Musculoskeletal examination and questionnaire of 36 volunteers of a music university and 19 volunteer students of an university of education were analyzed. The total number of musculoskeletal dysfunctions and differences between the student groups were examined. The personal pain and health self-rating were compared between music and non-music students.

RESULTS

Eighty one percent of musicians experienced PRMD. Musicians experienced 6.19 pain regions on average compared to 4.31 of non-musicians. Musicians experiencing PRMD reported significantly (P<0.05) more pain locations than musicians without. Music students presented with nearly the double amount (8.39 versus 4.37) of musculoskeletal dysfunctions per person compared to the non-music control group. Nevertheless, musicians significantly (P<0.05) rated their health more positively than the controls.

CONCLUSION

Musicians presented with more pain regions and a higher amount of musculoskeletal dysfunctions. Further studies evaluating the clinical relevance and their role in the development of PRMD are warranted.

CLINICAL REHABILITATION IMPACT

Screening of musicians for musculoskeletal dysfunction may identify those musicians at increased risk. Early treatment may prevent PRMD in musicians. Additional research is needed to confirm our hypothesis.

Dispersion-free pulse duration reduction of passively Q-switched microchip lasers

We present a dispersion-free method for the pulse duration reduction of passively Q-switched microchip laser (MCL) seed sources. This technique comprises two stages: one that carries out the self-phase modulation induced spectral broadening in a waveguide structure and a subsequent spectral filtering stage in order to shorten the pulses in time domain. The setup of a proof-of-principle experiment consists of a fiber-amplified passively Q-switched MCL, a passive single-mode fiber used as nonlinear element in which the spectrum is broadened, and a reflective volume-Bragg-grating acting as bandpass filter. A reduction of the pulse duration from 118 to 32 ps with high temporal quality has been achieved with this setup.

Sub-5-ps, multimegawatt peak-power pulses from a fiber-amplified and optically compressed passively Q-switched microchip laser

We report on high-energy picosecond pulse generation from a passively Q-switched and fiber-amplified microchip laser system. Initially, the utilized microchip lasers produce pulses with durations of around 100 ps at 1064 nm central wavelength. These pulses are amplified to energies exceeding 100 μJ, simultaneously chirped and spectrally broadened by self-phase modulation using a double stage amplifier based on single-mode LMA photonic crystal fibers at repetition rates of up to 1 MHz. Subsequently, the pulse duration of chirped pulses is reduced by means of nonlinear pulse compression to durations of 2.7 ps employing a conventional grating compressor and 4.7 ps using a compact compressor based on a chirped volume Bragg grating.

Oculocardiac Reflex in a Dog Caused by a Choroidal Melanoma with Orbital Extension

A 7 yr old mixed-breed dog was presented with a choroidal melanoma of the left eye that had penetrated the sclera, producing an orbital mass. Bradycardia was detected on auscultation. The bradycardia resolved after exenteration of the orbit and was therefore presumed to be associated with the oculocardiac reflex.

[Magnetic resonance imaging and ultrasonography in dogs and cats with ocular and orbital diseases. Part 1: Ocular diseases]

OBJECTIVE

This two-part study describes the clinical usefulness and value of ultrasound and magnetic resonance imaging (MRI) in dogs and cats with ocular (n=30) and orbital diseases (n=31). MRI and ultrasonography characteristics are described in single cases with ocular and orbital disease.

MATERIAL AND METHODS

Ultrasonography and MRI were performed in 15 dogs and 15 cats with intraocular neoplasia or intraocular inflammatory disease.

RESULTS

In all patients with intraocular neoplasia, sonography revealed masses with increased echogenicity and fairly uniform echotexture, thus allowing the tentative diagnosis of an intraocular tumour. In these cases, MRI often proved to be a valuable diagnostic tool in showing the complete extent of intraocular lesion. An additional benefit of MRI was seen in the tissue characterization of tumours based on MRI signal characteristics and pattern of contrast enhancement. Discreet intraocular inflammatory alterations, in particular to the anterior and posterior segment of the eyeball, were more clearly shown by ultrasound than by MRI. Neoplasia could be excluded and inflammatory disease was successfully diagnosed using MRI due to the different image sequences with or without contrast medium administration. Traumatic ruptures of the lens capsule and the globe after trauma were depicted more clearly with MRI.

CONCLUSIONS AND CLINICAL RELEVANCE

When opacity of the anterior eye segment is present, various intraocular changes can be quickly diagnosed by ultrasound with high accuracy, without requiring anaesthesia of the patient. MRI of the globe allows differentiation of diverse pathologies, gives detailed information of infiltration in orbital structures and the exact degree of ocular lesions after trauma. This additional evidence often makes it easier to predict the correct prognosis and choose the best therapy.

454 EST analysis detects genes putatively involved in ginsenoside biosynthesis in Panax ginseng

Panax ginseng C.A. Meyer is one of the most highly valued medicinal plants in the world. To analyze the transcriptome of P. ginseng and discover the genes involved in ginsenoside biosynthesis, cDNAs derived from the total RNA of 11-year-old, wood-grown P. ginseng roots were analyzed by 454 sequencing. A total of 217,529 high quality reads (expressed sequence tags, ESTs), with an average length of 409 bases, were generated from a one-quarter run to yield 31,741 unique sequences. The majority (20,198; 63.6%) of the unique sequences were annotated using BLAST similarity searches. A total of 16,810 and 16,577 unique sequences were assigned to functional classifications and biochemical pathways based on Gene Ontology analysis and the Kyoto Encyclopedia of Genes and Genomes assignment, respectively. Nine genes involved in the biosynthesis of ginsenoside skeletons and many candidate genes putatively responsible for modification of the skeletons, including 133 cytochrome P450s and 235 glycosyltransferases, were identified. From these candidates, six transcripts encoding UDP-glycosyltransferases that were most likely to be involved in ginsenoside biosynthesis were selected. These results open a new avenue by which to explore and exploit biosynthetic and biochemical properties that may lead to drug improvement. These 454 ESTs will provide the foundation for further functional genomic research into the traditional herb P. ginseng or its closely related species.

Surgical removal of a dermoid cyst from the bony part of the nasolacrimal duct in a Scottish highland cattle heifer

The ophthalmologic, radiologic and surgical findings of a 2-year-old Scottish Highland Cattle heifer with a dermoid cyst within the bony part of the nasolacrimal duct and the successful treatment are presented.

Blindness as a sign of proventricular dilatation disease in a grey parrot (Psittacus erithacus erithacus)

An approximately eight-year-old female grey parrot (Psittacus erithacus erithacus) was presented with a two months history of blindness. The radiographic examination showed a dilatation of the proventriculus, ventriculus and gut. Ophthalmoscopy and electroretinography revealed degeneration of the retina. A proventricular dilatation disease was suspected. The bird was euthanased because of deteriorating condition and poor prognosis. The pathological examination showed an atrophy of the ventricular muscles and lymphoplasmacytic infiltrates of the myenteric plexus of the proventriculus, ventriculus and gut as well as moderate lymphoplasmacytic infiltrates of the cerebrum with moderate neuronophagia. Lymphoplasmacytic infiltrates in the retina, indicating proventricular dilatation disease, and subsequent retinal degeneration were found. A potential common aetiology for proventricular dilatation disease and blindness is discussed.

Factors affecting intraocular pressure in lions

The aim of this study was to conduct a detailed analysis of the relationship between age and intraocular pressure (IOP) in lions. Tonometry was conducted in 33 lions aged 5 days to 80 months. Age was significantly associated with IOP (P<0.005). Mean IOP was 12.8+/- and 23.9+/-4.1 mmHg in lions < or =1 year old and >1 year old, respectively. IOP linearly rose with age during the first 20 months of life, plateaued until approximately 40 months, and then gradually declined (r=0.85). Age-related changes in IOP were highly correlated with ultrasonographic measurements of intraocular dimensions (r > or = 0.72), and may be a determinant factor in developmental ocular growth. The dramatic rise in IOP of young lions is similar to that observed in children, but has not been previously demonstrated in animals. Significant IOP differences between lion sub-species were also demonstrated.

Search for Lorentz and CPT violation effects in Muon spin precession

The spin precession frequency of muons stored in the (g-2) storage ring has been analyzed for evidence of Lorentz and CPT violation. Two Lorentz and CPT violation signatures were searched for a nonzero delta omega a(=omega a mu+ - omega a mu-) and a sidereal variation of omega a mu+/-). No significant effect is found, and the following limits on the standard-model extension parameters are obtained: bZ = -(1.0+/-1.1) x 10(-23) GeV; (m mu dZ0 + HXY)=(1.8+/-6.0) x 10(-23) GeV; and the 95% confidence level limits b perpendicular mu+ <1.4 x 10(-24) GeV and b perpendicular mu- <2.6 x 10(-24) GeV.