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.

[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.

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.

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.

Das Management des Glaukoms bei Hund und Katze

Das Glaukom als akuten Notfall zu erkennen und umgehend eine drucksenkende Therapie einzuleiten, ist die Grundvoraussetzung für den Erhalt der Sehkraft des betroffenen Auges. Beim Vorliegen eines Sekundärglaukoms ist die Beseitigung der Ursache wesentlicher Bestandteil der Behandlung. Tiere mit einem Primärglaukom bleiben in der Regel nach einem initialen Druckanstieg lebenslang “Augenpatienten”, die einer regelmäßigen, frequenten Kontrolle bedürfen. Diese dient der individuellen Therapieanpassung. Die therapeutischen Möglichkeiten umfassen sowohl medikamentöse als auch chirurgische Maßnahmen. Ein aufgrund eines Glaukoms irreversibel erblindetes Auge (Buphthalmus) sollte chirurgisch entfernt werden.

Quantitative Lung Perfusion Following Single Lung Transplantation

BACKGROUND

Following successful lung transplantation, most of the lung perfusion, as well as ventilation, is shifted towards the transplanted lung. We investigated the changes in perfusion during exercise in lung transplant recipients.

PATIENTS AND METHODS

Twelve patients were included in the study. Six patients had emphysema and 6 patients had idiopathic pulmonary fibrosis (IPF). Patients underwent two upright lung perfusion scans: the first at rest and the second during a maximal cardiopulmonary exercise test. Lung perfusion was assessed in each lung and regionally.

RESULTS

At rest, patients with emphysema had 83.3 +/- 8 % of total perfusion to the transplanted side and 16.7 +/- 8 % to the native lung, while in the IPF patients, it was 68.7 +/- 12 and 32.7 +/- 10 %, respectively ( P = 0.028). At peak exercise, perfusion shifted from the transplanted lung to the native lung ( P = 0.0095) both in emphysema and IPF patients.

CONCLUSIONS

Following successful lung transplantation, most of the perfusion is directed towards the transplanted lung. During exercise, there was a small but significant shift towards the native lung. These findings highlighted the important role of the native lung during maximal exercise.

Chronische Therapie des metabolischen Syndroms bei herzoperierten Diabetikern

Patients with type 2 diabetes often also exhibit additional features of the metabolic syndrome. These include specifically central obesity triggering development and maintenance of diabetes together with arterial hypertension, hypertriglyceridemia and low levels of high-density lipoprotein cholesterol. Chronic therapy of the metabolic syndrome in diabetics after coronary bypass surgery focuses on changes in lifestyle, i.e., cessation of smoking, changes in nutrition and increase in physical activity. Nutrition aims at fat reduction and modification to reduce saturated fatty acids, to allow mono- and polyunsaturated fatty acids instead, and moderate alcohol consumption. High fiber and complex carbohydrate diet complete the recommendations. Nutrition therapy connected to increases in physical activity are aimed at reducing weight in overweight and obese subjects, which should reduce their body weight by 5 to 10% within about 6 months. Normal weight subjects benefit from increases in physical activity by lipid and glucose regulation as well as by reduction in mortality.Diabetes-specific therapy aims at normoglycemia including postprandial blood glucose levels, reduces blood pressure supported by ACE inhibitors and aims at weight reduction. Reduction of LDL-cholesterol is the first line therapy, also diminishing small-dense LDL particles. Decreasing triglycerides and increasing HDL-cholesterol are further lipid-regulating aims. Specifically diabetics after coronary bypass surgery need LDL-cholesterol levels below 70 mg/d (1.8 mmol/L) and triglycerides below 150 mg/dL (1.7 mmol/L). In addition, in males HDL-cholesterol should be at least above 40 mg/dl (1 mmol/L), in females above 50 mg/dL (1.3 mmol/L).

Empfehlungen zur Statintherapie im Alter

Elderly patients are significantly less likely to receive statins than younger patients possibly because of doubts regarding compliance or concerns regarding the increased likelihood of adverse events and drug interactions. Poor compliance can be expected especially in patients suffering from dementia or depression as well as those whose stage of cardiovascular disease exhibits few symptoms. On the other hand, the clinical significance of CHD events is high in the elderly, and 80% of coronary deaths occur in patients aged over 65 years. The average statistical life expectancy of elderly and old patients is often underestimated. The HPS and PROSPER studies showed that statins reduce mortality and morbidity even in very elderly individuals with a high global cardiovascular risk and/or CAD. Patients up to the age of 79 years should be treated according to the same guidelines as younger patients. Statin therapy should only be considered for patients aged 80 years and older who are at a very high risk for cardiovascular events.

Prevention of brain metastasis formation by local expression of interleukin-4 or hemagglutinin antigen

INTRODUCTION

Expression of hemagglutinin antigen of influenza virus (HA) by the murine colon carcinoma cell line (CT-26) produces systemic immunization against tumor challenges in the cecum, liver and lungs but not in the brain of BALB/c-mice. Immunization with IL-4 expressing CT-26 cells inhibits lung metastases formation. The purpose of our study was to examine the effects of HA or IL-4 expression on brain metastases formation.

METHODS

Using selective internal carotid artery injections, brain metastases formation of HA or IL-4 expressing CT-26 cells with and without subcutaneous pre-immunization was evaluated in Balb/c mice.

RESULTS

Systemic pre-immunization with HA or IL-4 expressing tumor cells cannot protect against brain metastases, while the local, intracerebral expression of HA or IL-4 inhibits the growth of hematogenous brain metastases.

CONCLUSION

Pre-immunization with HA or IL-4 expressing tumor cells did produce systemic immunity against liver and lung metastases but not against brain metastases. Local, intracerebral expression of HA or IL-4 prevents from cerebral metastases formation in an animal model.

Treatment of diabetic dyslipoproteinemia

Diabetes mellitus, specifically type 2, is often associated with disorders in lipid metabolism. Elevated levels of plasma free fatty acids play a pivotal role by contributing significantly to insulin resistance. In addition free fatty acids promote diabetic dyslipidemia through increasing VLDL synthesis in the liver, and by virtue of cholesterylester transfer protein, modifying LDL to increase small-dense LDL subfractions and to decrease HDL cholesterol. This atherogenic lipoprotein profile (elevated triglycerides, increased small-dense low-density lipoproteins, and decreased high-density lipoproteins), contributes to the development of atherosclerosis and increases the risk of experiencing cardiovascular events, the most common cause of death in type 2 diabetes. To decrease the risk of cardiovascular disease events in diabetics, dyslipidemia needs to be treated, as evidenced from epidemiology, from intervention trials, and from subgroup analyses of large intervention trials initiated to evaluate effects of lipid lowering treatment that also included patients with type 2 diabetes. Most measures used to counteract hyperglycemia, are also prone to ameliorate dyslipidemia: dietary intervention (medical nutrition) including omega-3 fatty acids as part of lifestyle changes that also comprise cessation of smoking, increases in physical activity and reduction in body weight. In addition insulin, biguanides, acarbose and glitazones applied for glycemic control also improve diabetic dyslipidemia. Additional pharmacological treatment of dyslipidemia if persisting after glycemic control relies on different drug classes. Fibrates effectively reduce free fatty acids, fasting and postprandial lipemia, shift the distribution of LDL particles towards less dense subfractions and increase HDL cholesterol, thus particularly addressing key components of diabetic dyslipidemia. For LDL cholesterol lowering statins are mainly used that decrease LDL cholesterol levels by competitive inhibition of the HMG-CoA reductase. As type 2 diabetes is found to be associated with a two- to fourfold increase in coronary heart disease risk and as the degree of glycemia is more related to microvascular complications, correcting dyslipidemia appears to be a major task in order to reduce macrovascular events in patients with type 2 diabetes.

Neutralizing immunogenicity of transgenic carrot (Daucus carota L.)-derived measles virus hemagglutinin

Although edible vaccines seem to be feasible, antigens of human pathogens have mostly been expressed in plants that are not attractive for human consumption (such as potatoes) unless they are cooked. Boiling may reduce the immunogenicity of many antigens. More recently, the technology to transform fruit and vegetable plants have become perfected. We transformed carrot plants with Agrobacterium tumefaciens to generate plants (which can be eaten raw) transgenic for an immunodominant antigen of the measles virus, a major pathogen in man. The hemagglutinin (H) glycoprotein is the principle target of neutralizing and protective antibodies against measles. Copy numbers of the H transgene were verified by Southern blot and specific transcription was confirmed by RT-PCR. The H protein was detected by western blot in the membrane fraction of transformed carrot plants. The recombinant protein seemed to have a 8% lower molecular weight than the viral protein. Although this suggests a different glycosylation pattern, proper folding of the transgenic protein was confirmed by conformational-dependent monoclonal antibodies. Immunization of mice with leaf or root extracts induced high titres of IgG1 and IgG2a antibodies that cross-reacted strongly with the measles virus and neutralized the virus in vitro. These results demonstrate that transgenic carrot plants can be used as an efficient expression system to produce highly immunogenic viral antigens. Our study may pave the way towards an edible vaccine against measles which could be complementary to the current live-attenuated vaccine.

Measurement of the positive muon anomalous magnetic moment to 0.7 ppm

A higher precision measurement of the anomalous g value, a(mu)=(g-2)/2, for the positive muon has been made at the Brookhaven Alternating Gradient Synchrotron, based on data collected in the year 2000. The result a(mu(+))=11 659 204(7)(5)x10(-10) (0.7 ppm) is in good agreement with previous measurements and has an error about one-half that of the combined previous data. The present world average experimental value is a(mu)(expt)=11 659 203(8)x10(-10) (0.7 ppm).

[Increased triglycerides and/or low HDL cholesterol. A risk factor needing treatment?]

Elevated LDL (low density lipoprotein) cholesterol is considered an established risk factor for the development of atherosclerotic sequelae. In this context, low HDL cholesterol and/or raised triglyceride levels are now also receiving increasing attention as independent risk factors for atherosclerosis. The protective HDL cholesterol should be as high as possible (> 40 mg/dl or 1.0 mmol/l). Low HDL cholesterol levels are associated with an increased coronary risk that cannot be eliminated by lowering LDL cholesterol concentrations. Measures to elevate HDL are primarily dietary adjustments, cessation of smoking, weight reduction and increased physical activity. Triglyceride levels above 1000 mg/dL are also associated with an increased risk for the development of pancreatitis, and therefore also need to be treated.

Treatment of dyslipoproteinemia in the metabolic syndrome

The metabolic syndrome consists of a cluster of metabolic disorders, many of which promote the development of atherosclerosis and increase the risk to develop cardiovascular disease. The metabolic syndrome is characterized by atherogenic dyslipidemia (elevated triglycerides, increased small dense low-density lipoproteins, and decreased high-density lipoproteins), hypertension, insulin resistance and obesity. To decrease the risk of cardiovascular disease events decreasing body weight by ingesting a healthy diet, increasing physical activity, cessation of smoking and managing dyslipidemia are recommended. Pharmacological treatment of dyslipidemia is based on different drug classes. For LDL-cholesterol-lowering mainly statins and for triglyceride-lowering mainly fibrates are used. In primary and secondary prevention trials of heart disease they have shown to reduce the incidence of coronary artery disease or coronary events by 25-60 percent. Statins reduce mainly LDL-cholesterol levels by competitive inhibition of HMG-CoA reductase but have also shown to reduce fasting and postprandial triglyceride levels. Fibrates effectively reduce fasting and postprandial lipemia, shift the distribution of LDL particles towards less dense particles and increase HDL-cholesterol. Thus fibrates particularly address components of the metabolic syndrome and features of diabetic dyslipidemia. However studies still are needed showing definite evidence on differential therapy in lipid lowering based on prospective controlled trials with endpoints of macro- and microangiopathy in diabetic patients.

X-ray structure of the orphan nuclear receptor RORbeta ligand-binding domain in the active conformation

The retinoic acid-related orphan receptor beta (RORbeta) exhibits a highly restricted neuronal-specific expression pattern in brain, retina and pineal gland. So far, neither a natural RORbeta target gene nor a functional ligand have been identified, and the physiological role of the receptor is not well understood. We present the crystal structure of the ligand-binding domain (LBD) of RORbeta containing a bound stearate ligand and complexed with a coactivator peptide. In the crystal, the monomeric LBD adopts the canonical agonist-bound form. The fatty acid ligand-coactivator peptide combined action stabilizes the transcriptionally active conformation. The large ligand-binding pocket is strictly hydrophobic on the AF-2 side and more polar on the beta-sheet side where the carboxylate group of the ligand binds. Site-directed mutagenesis experiments validate the significance of the present structure. Homology modeling of the other isotypes will help to design isotype-selective agonists and antagonists that can be used to characterize the physiological functions of RORs. In addition, our crystallization strategy can be extended to other orphan nuclear receptors, providing a powerful tool to delineate their functions.

Surgical management of single and multiple brain metastases: results of a retrospective study

BACKGROUND

Advancement in diagnosis and treatment of various cancer entities led to an increasing incidence of brain metastases in the last decades. Surgical excision of single and multiple brain metastases is one of the central treatment options beside radiotherapy, radiosurgery and chemotherapy. To evaluate the benefit of surgery with/without whole-brain radiation therapy (WBRT) in single brain metastases and the influence of image guidance for brain metastases resection, 104 patients were retrospectively evaluated for post-operative outcome.

PATIENTS AND METHODS

Between January 1994 and December 1999 150 patients were surgically treated for brain metastases at the Department of Neurosurgery at the Technical University of Dresden. Outcome could be evaluated in 104 patients with respect to special treatment strategies and survival time (69 patients with single and 35 patients with multiple lesions).

RESULTS

Most metastases originated from primary lung and breast tumours. Karnofsky performance score improved on average by 10 after surgery. The extent of the extracerebral tumour burden was the main influence on survival time. Patients' age below 70 years was combined with prolonged survival time (median survival time, MST: 4.5 months vs. 7 months). Patients with solitary cerebral metastasis had a MST of 16 months, whereas patients with singular lesions had a MST of 7 and 4 months, depending on the extent of the extracerebral tumour growth. Additional post-operative WBRT with 30 Gy was combined with an increase in MST in patients with single brain metastasis (surgery + WBRT: MST 13 months; surgery only: MST 8 months). In addition, the rate of recurrent cerebral tumour growth was distinctly higher in the non-WBRT group. Neuronavigation did not significantly improve post-operative survival time. In 80% of patients extracerebral tumour growth limited patients' survival.

CONCLUSION

Surgery is an initial treatment option in patients with single and multiple brain metastases especially with large tumours (> 3 cm). Post-operative WBRT seems to prolong survival time in patients with single brain metastasis by decreasing local and distant tumour recurrence. Neuronavigational devices permit a targeted approach. Multiple processes can be extirpated in one session without prolonging the hospitalisation time for the patient. However, neuronavigational devices cannot assure complete tumour resection.

Precise measurement of the positive muon anomalous magnetic moment

A precise measurement of the anomalous g value, a(mu) = (g-2)/2, for the positive muon has been made at the Brookhaven Alternating Gradient Synchrotron. The result a(mu+) = 11 659 202(14) (6) x 10(-10) (1.3 ppm) is in good agreement with previous measurements and has an error one third that of the combined previous data. The current theoretical value from the standard model is a(mu)(SM) = 11 659 159.6(6.7) x 10(-10) (0.57 ppm) and a(mu)(exp) - a(mu)(SM) = 43(16) x 10(-10) in which a(mu)(exp) is the world average experimental value.