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Numerous biogenic volatile organic compounds (VOC) species are released into the atmosphere from tropical forests. Measuring all those which are relevant for atmospheric chemistry or for the carbon budget is challenging. Large-Scale Biosphere-Atmosphere (LBA) Experiment field campaigns substantially increased the number of field studies of isoprene and monoterpene emissions, as well as of the exchange of several other VOC species. This chapter reports about the progress made within LBA from primary emission measurements at the plant species level up to discussions of the oxidative capacity of the atmosphere and formation of secondary organic aerosol particles and cloud condensation nuclei from biogenic hydrocarbons. VOC emission from Amazonian ecotypes has strong effects on atmospheric chemistry, which are obviously not fully understood in the case of the tropical atmosphere. Atmospheric flux studies within numerous field experiments resulted in new knowledge about local to regional scale biogenic VOC exchange and improved modeling. New data obtained from field as well as from laboratory studies helped to characterize VOC emissions from the Amazonian forest underlying seasonality within dry and wet seasons. Furthermore, first insight was obtained into the potential of floodplain areas affected by long-lasting flooding periods which can cause special emission adaptation. © Copyright 2009 by the American Geophysical Union.

As part of the OSOA (Origin and formation of Secondary Organic Aerosols) project, two intensive field campaigns were conducted in Melpitz, Germany and Hyytiälä, Finland. This paper gives an overview of the measurements made during the Hyytiälä campaign, which was held between 1 and 16 August 2001. Various instrumental techniques were used to achieve physical and chemical characterisation of a erosols and to investigate possible precursor gases. During the OSOA campaign in Hyytiälä, particle formation was observed on three consecutive days at the beginning of the campaign (1 to 3 August 2001) and on three days later on. The investigation of the meteorological situation divided the campaign into two parts. During the first three days of August, relatively cold and clean air masses from northwest passed over the station (condensation sink-CS:

Background: Molecular targeted therapies for astrocytic tumors are the subject of growing research interest, due to the limited response of these tumors, especially glioblastoma multiforme, to conventional chemotherapeutic regimens. Several of these approaches exploit the inhibition of receptor tyrosine kinases. To date, it has not been elucidated if fms-like tyrosine kinase-3 (Flt3) and its natural ligand (Flt3L) are expressed in astrocytic tumors, although some of the clinically intended small-molecule receptor tyrosine kinase inhibitors affect Flt3, while others do not. More importantly, the recent proof of principle for successful stimulation of the immune system against gliomas in preclinical models via local Flt3L application requires elucidation of this receptor tyrosine kinase pathway in these tumors in more detail. This therapy is based on recruitment of Flt3-positive dendritic cells, but may be corroborated by activity of this signaling pathway in glioma cells. Methods: Receptor and ligand expression was analyzed by real-time polymerase chain reaction in 31 astrocytic tumors (six diffuse and 11 anaplastic astrocytomas, 14 glioblastomas) derived from patients of both genders and in glioblastoma cell lines. The two most common activating mutations of the Flt3 gene, ie, internal tandem duplication and D835 point mutation, were assessed by specific polymerase chain reaction. Results: A relatively high abundance of Flt3L mRNA (4%-6% of the reference, b2 microglobulin) could be demonstrated in all tumor samples. Flt3 expression could generally be demonstrated by 40 specific polymerase chain reaction cycles and gel electrophoresis in 87% of the tumors, including all grades, although the small quantities of the receptor did not allow reliable quantification. Expression of both mRNAs was verified in the cell lines, excluding a derivation solely from contaminating lymphocytes or macrophages. No activating mutations were found. Conclusion: Our results warrant further analysis of endogenous Flt3 signaling in these tumors prior to application of immunotherapy in human patients. [ABSTRACT FROM AUTHOR]

The built-up of oligomeric compounds during secondary organic aerosol (SOA) formation is subject of atmospheric research since several years. New particle formation and especially the SOA mass yield might be influenced significantly by oligomer formation. However, the chemical nature of observed oligomers and their formation pathways are still unclear. In this paper, the structural characterization of certain dimeric compounds (esters) formed during the ozonolysis of cyclohexene and cyclohexene/α-pinene mixtures are presented. The identification is based on the comparison of the mass spectra and the retention times (LC) of the oligomeric products with synthesized reference compounds. Cyclohexene is used here as a model compound for terpenes as globally most important SOA precursors, since it possesses a simpler structure than the biogenic alkenes and therefore offers the possibility to get access to reference compounds for certain of its oxidation products. In addition to cyclohexene, the formation of esters could also be observed in experiments with α-pinene as reactant. [ABSTRACT FROM AUTHOR]

Health information is indispensable for monitoring the progress that has been made in improving and maintaining population health and health system functions. In the context of health reforms aiming to bring health systems closer to populations and with the objective of consistent health services planning at the community level, access to reliable social and health data has become a major issue. The need to develop specific treatment tools and the appropriation of results by the various actors involved (decision makers, planners, researchers and consumers) are central to the presentations and exchanges in this symposium.

Many newly licensed nurses begin their careers with limited knowledge and experience in end-of-life care. Findings from a literature review and a learning needs assessment of newly licensed nurses at a comprehensive cancer center guided the development of an 8-hour educational program on end-of-life care. An experiential learning approach was used to foster confidence and develop knowledge and skills in delivery of end-of-life care by newly licensed nurses., (Copyright 2014, SLACK Incorporated.)

Objective: Our research uses a regional summary indicator (IHPOLM) to measure the capacity of the health system to provide equitable access to health professionals for 2 million Official Language Minority Community (OLMC) members dispersed across 104 health regions in Canada., Method: The summary indicator IHPOLM compares the official language minority and the official language majority potential access to health professionals. The IHPOLM indicator uses 22 professional health care occupations, representing 79% of the health care workforce in Canada, who communicate directly with their clientele for therapeutic or diagnostic purposes (Statistics Canada, 2006)., Results: The IHPOLM indicator revealed that the OLMC population is at a disadvantage in potential access to health professionals capable of providing services in the minority language when compared to the majority language population in 10 of the 13 Canadian provinces/territories. OLMC members are disadvantaged in 13 out of 14 health regions in Ontario, in 16 out of 18 in Québec and in 3 out of 7 in New Brunswick., Conclusion: The summary regional indicator IHPOLM identified OLMC health care access inequalities between the official language minority population and the majority language population in the health care system across the health regions in Canada. The more detailed analysis of IHPOLM for individual health occupations will further improve our knowledge of Official Language Minority Community health access inequalities.

Atomic force microscopy (AFM) force spectroscopy is a technique with broad nanomedical applications, widely used for the characterization of molecular interactions on the nanoscale. Here we test this technique to evaluate compounds for influencing the protein aggregation process. The results demonstrate that Zn(2+) or Al(3+) cations bring about a dramatic increase of α-synuclein interactions in unfavorable conditions for α-synuclein misfolding (neutral pH). We did not observe the effect of dopamine at favorable conditions for α-synuclein misfolding (acidic pH). We also found that electrostatic interactions do not play a significant role at acidic pH. These findings are generally in line with previous studies by various techniques. The high sensitivity of AFM force spectroscopy as well as its ability to test compounds for the same experimental system makes AFM an efficient nanotool for rapid analysis of compounds inhibiting early protein aggregation studies and quantitative selection of potential therapeutics for neurodegenerative diseases., From the Clinical Editor: Atomic force microscopy is used to interrogate the influence of cations and α-synuclein on the protein aggregation process. The report illustrates an application of AFM to unravel the potential of novel therapeutics on early protein aggregation intrinsic in neurodegenerative diseases., (Copyright © 2011 Elsevier Inc. All rights reserved.)

On-line ion trap mass spectrometry (ITMS) enables the real-time characterization of reaction products of secondary organic aerosol (SOA). The analysis was conducted by directly introducing the aerosol particles into the ion source. Positive-ion chemical ionization at atmospheric pressure (APCI(+)) ITMS was used for the characterization of constituents of biogenic SOA produced in reaction-chamber experiments. APCI in the positive-ion mode usually enables the detection of [M+H](+) ions of the individual SOA components. In this paper the identification of organic peroxides from biogenic volatile organic compounds (VOCs) by on-line APCI-ITMS is presented. Organic peroxides containing a hydroperoxy group, generated by gas-phase ozonolysis of monoterpenes (alpha-pinene and beta-pinene) and sesquiterpenes (alpha-cedrene and alpha-copaene), could be detected via on-line APCI(+)-MS/MS experiments. A characteristic neutral loss of 34 Da (hydrogen peroxide, H(2)O(2)) in the on-line MS/MS spectra is a clear indication for the existence of an organic peroxide, containing a hydroperoxy functional group., (Copyright (c) 2009 John Wiley & Sons, Ltd.)

The molecular composition of PM2.5 (particulate matter with an aerodynamic diameter <2.5 microm) aerosol samples collected during a very warm and dry 2003 summer period at a mixed forest site in Jülich, Germany, was determined by gas chromatography/mass spectrometry in an effort to evaluate photooxidation products of biogenic volatile organic compounds (BVOCs) and other markers for aerosol source characterization. Six major classes of compounds represented by twenty-four individual organic species were identified and measured, comprising tracers for biomass combustion, short-chain acids, fatty acids, sugars/sugar alcohols, and tracers for the photooxidation of isoprene and alpha-/beta-pinene. The tracers for the photooxidation of alpha-/beta-pinene include two compounds, 3-hydroxyglutaric acid and 3-methyl-1,2,3-butanetricarboxylic acid, which have only recently been elucidated. The characteristic molecular distribution of the fatty acids with a strong even/odd number carbon preference indicates a biological origin, while the presence of isoprene and terpene secondary organic aerosol products suggests that the photooxidation of BVOCs contributes to aerosol formation at this site. The sum of the median concentrations of the isoprene oxidation products was 21.2 ng m(-3), while that of the terpene oxidation products was 19.8 ng m(-3). On the other hand, the high median concentration of malic acid (37 ng m(-3)) implies that photooxidation of unsaturated fatty acids should also be considered as an important aerosol source process. In addition, the occurrence of levoglucosan and pyrogallol indicates that the site is affected by biomass combustion. Their median concentrations were 30 and 8.9 ng m(-3), respectively.

Aim: Tethered cord syndrome (TCS) is a stretch-induced functional disorder of the spinal cord, which is directly related to filum fixation. Classic surgical approaches to the filum involve open surgery and include varying amounts of spinal bone removal. In an effort to reduce the morbidity and mortality of these procedures, the authors explored a less invasive method. They evaluated the ability, safety and feasibility for endoscopic sectioning of the filum terminale externum by performing upward orientated navigation in the extradural sacral spinal canal through the sacral hiatus using a rigid endoscope., Methods: Four adult, phenol-formalin embalmed cadavers were used for endoscopic section of the filum terminale externum at the tip of thecal sac. After preparing the anatomical area of sacral hiatus, a rigid endoscope (Storz, of 3.8 mm external diameter with two working channels, of 1 mm each, one for suction-irrigation and one as working) was inserted into the extradural sacral spinal canal and the filum terminale externum was identified and cut easily at the distal end of thecal sac at the level of S2. In all cases, it was possible to manipulate the rigid endoscope and inspect the full length of the extradural sacral spinal canal, especially at the S1-S2 level., Results: The results indicate that the tested transhiatal approach for upward orientated extradural endoscopy represents a minimally invasive procedure that provides an appropriate and feasible route to the extradural sacral spinal canal., Conclusion: Such approach is an attractive alternative for filum terminale externum sectioning in cases where tethered cord syndrome is not accompanied by any other pathology. Moreover if filum terminale internum sectiong is indicated, it can be performed in second stage.

The formation of secondary organic aerosols (SOA) has been investigated intensively during the last two decades in numerous field and laboratory studies and a general understanding exists about the major particle-phase products. However, recent studies show that several new product classes, such as esters, peroxides or organosulfates, also have to be considered in order to understand the detailed chemical mechanisms leading to SOA as well as to predict the aerosol mass loadings. For the identification and quantification of these three compound classes as well as for carboxylic SOA compounds, liquid chromatography (LC)/mass spectrometry (MS) is the most appropriate analytical method. In this article we try to summarize briefly the work that has been done for the determination of SOA-related carboxylic acids and we present new LC/tandem MS results on the characterization of esters, peroxides and organosulfates. In contrast to earlier work, the mass-spectrometric characterization of the individual compounds is always based on the comparison with authentic reference compounds.

Epidemiological studies show a clear link between increased mortality and enhanced concentrations of ambient aerosols. The chemical and physical properties of aerosol particles causing these health effects remain unclear. A major fraction of the ambient aerosol particle mass is composed of secondary organic aerosol (SOA). Recent studies showed that a significant amount of SOA consists of high molecular weight compounds (oligomers), which are chemically not well characterized. Within the POLYSOA project a large variety of state-of-the-art analytical chemical methods were used to characterize the chemical composition of SOA particles with emphasis on the oligomeric mass fraction. Mass spectrometric results showed that SOA oligomers are highly oxidized compounds and that hydroperoxides are formed, which is consistent with NMR results. This high molecular weight fraction accounts for up to 23% of the total organic carbon in SOA particles. These well-characterized SOA particles were deposited on three lung cell culture systems (microdissected respiratory epithelia from porcine tracheae, the human bronchial epithelial cell line BEAS-2B, and porcine lung surface macrophages obtained by bronchoalveolar lavage) in a newly constructed particle deposition chamber with the goal to eventually identify particle components that are responsible for cell responses leading to adverse health effects. In addition, monolayers of the alveolar epithelial cell line A549 were used in an alveolar epithelial repair model. The lung cells were examined for morphological, biochemical, and physiological changes after exposure to SOA. Analyses of the lung cells after exposure to SOA are ongoing. First data give evidence for a moderate increase of necrotic cell death as measured by lactate dehydrogenase release and for effects on the alveolar epithelial wound repair mainly due to alterations of cell spreading and cell migration at the edge of the wound. Thus, these first results indicate that SOA, in concentrations comparable to environmental concentrations, may induce distinct effects in lung cells.

Background: Adhesive lumbar arachnoiditis is essentially an unknown, unreported, and unrecognised disease. It was better known at a time when oil-based dye was used for myelography. The factors causing this pathogenesis remain unknown. In addition, diagnosis is hard to achieve and frequently attained only by an exclusion process. Only in severe cases, using high-resolution MRI, is evidence for the diagnosis obtainable., Method/patients: Modern neuroendoscopic techniques allow diagnosis at a reasonable risk (comparable with lumbar tap) and enable us substantially to treat the pain. Taken together, this means a radical new method of treatment for adhesive arachnoiditis. The treatment of a 23-patient research group suffering from adhesive lumbar arachnoiditis is monitored and described., Results: Various endoscopic manoeuvres were carried out. Endoscopic reduction of adhesions and internal shunting for CSF flow between subarachnoidal and epidural space improved both the biomechanical abilities of rootlets and restoration of blocked CSF pathways. Its main result is the significant reduction of long-term pain registered by a visual analogue pain scale. No bad side effect other than temporary headache was found. No CSF leak syndrome was observed., Discussion: The success of the method was directly influenced by the interventional procedure on the disturbed CSF circulation and its partial restoration (subarachnoepidurostomy). In cases of severe lumbar adhesive arachnoiditis, it was found very beneficial to implant special gravity-controlled valve systems for subarachnoid-peritoneal shunts., Conclusion: Adhesive lumbar arachnoiditis is no longer a devastating diagnosis. Due to a novel endoscopic treatment of the local CSF disturbances that restores physiologic pathways, the chance exists for long-lasting improvement of the clinical condition.

Introduction: Endoscopy of the lumbar subarachnoidal space is named thecaloscopy, which has been used for diagnostic and therapeutic purposes. However, the insertion of the endoscope required microsurgical assistance from the skin into thecal sac in the lumbar region. The current study was applied to explore the possibility of a percutaneous approach for lumbar thecaloscopy insertion, transferring from the previous microsurgical procedure., Method: A 2.8-mm fiberoptic endoscope (Storz and Co., Tuttlingen, Germany) was used in the study. In two fresh human cadavers, a thecaloscope was first inserted through a transsacral approach and the tip was advanced inside the thecal sac to the lumbar region for observation. A percutaneous endoscopic approach was performed with the Seldinger technique under fluoroscopic control into the lumbar subarachnoid space. After completing the endoscopic procedure, the lumbar subarachnoid space was exposed microsurgically for morphological investigation of rootlets and surrounding structures., Results: By the observation through a live video in the thecal sac, the percutaneous insertion of a 2.8-mm endoscope into the lumbar subarachnoidal space is feasible without any neural structural damage seen., Conclusion: The percutaneous approach for flexible endoscopes into the lumbar subarachnoidal space is a practical option for the future of thecaloscopy.

In this study the ability for upward-orientated endoscopic visualization of thecal subarachnoid space using a flexible steerable endoscope was evaluated in order to compare endoscopic anatomical findings with the already known macroscopic ones of the incontained structures and to test the approach for clinical employment. For this purpose, four adult phenol-formalin embalmed cadavers were used and the approach selected was through a laminectomy window at the S1-S2 level. The dura mater was opened and a flexible steerable endoscope (Storz, of 2.8 mm external diameter with one working channel) was inserted subarachnoidally for upward-orientated observation of the content of thecal sac. By using this approach filum terminale, lower lumbar, sacral and coccygeal nerve rootlets were identified and observed in detail. By moving the endoscope even more upwards, inspection of the upper part of the thecal subarachnoid space and conus medullaris was also possible. The findings collected from the study indicate that this approach for upward-orientated intradural subarachnoid endoscopy gives an appropriate working and inspecting window to the lower, as well as to the upper part of the thecal subarachnoid space and even of the conus medullaris. Furthermore, inspection and identification of lower lumbar, sacral and coccygeal nerve rootlets is possible and efficient and the endoscopic anatomical observations coincide with the already known gross-anatomical ones.

Objective: The diagnosis of lumbar arachnoiditis remains complex and often inconclusive. Using the technique of lumbar subarachnoidal endoscopy (thecaloscopy), the pathology can be identified and the patient treated with long-term effects on the symptoms., Method: Endoscopic operations were performed on 23 patients suffering from varying symptoms with an enlarged lumbar subarachnoidal space. Having confirmed the diagnosis of lumbar arachnoiditis, a number of endoscopic operations ranging from adhesiolysis to subarachno-epidurostomy were carried out., Results: Radicular symptoms in lumbar arachnoiditis were successfully relieved by various endoscopic dissection techniques, such as restoration of the improved CSF flow by subarachno-epidurostomy along the rootlet. This has been identified as one of the causal factors of the clinical symptoms. In cases where lumbar pain persists in spite of a previous thecaloscopy, further treatment with a lumboperitoneal shunt device has proved most successful.

A method is presented for the determination of acidic products from terpene oxidation in filter samples of the atmospheric particle phase. Oxidation products of monoterpenes are believed to add a large fraction to the secondary organic aerosol (SOA) in the troposphere. Those products with structures containing one or more carboxylic acid groups have especially low vapour pressures and therefore they are believed to contribute substantially to the particle phase. Although many experiments were performed in simulation chambers to study the SOA generation by oxidation of terpenes, concentration measurements of products in the atmospheric particle phase are still rare. This is especially true for oxidation products of terpenes other than alpha- and beta-pinene. Therefore, we developed a method for the quantification of acidic products from terpene oxidation in atmospheric aerosol samples. After passing a PM 2.5 (PM = particulate matter) pre-separator to remove coarse particles, fine atmospheric particles were collected onto quartz fibre filters. A backup filter was placed behind the first filter to estimate possible sampling artifacts. The filters were extracted in an ultrasonic bath using methanol. After enrichment and re-dissolving in water the samples were analysed using a capillary-HPLC-ESI(-)-MS(n) set-up. The ion trap mass spectrometer could be used to gain structural information about the analytes and to enhance the selectivity of the measurements by using its MS/MS capability. A variety of products from different terpenes could be identified and quantified in samples of the ambient atmosphere using reference data from chamber experiments. Due to strong matrix effects quantification of samples from the real atmosphere had to be done by the standard addition method.

Endoscopy of the spinal canal, for interventional studies, diagnosis and therapy, is a scientific topic that has attracted the interest of neurosurgeons, anesthesiologists and orthopedic surgeons for the past twenty years. Endoscopy of the thecal sac was assumed to be less important than endoscopy of the ventricular system by neurosurgeons. Nevertheless, during the last years it has attained increasing scientific interest, firstly because of the introduction of small diameter flexible endoscopes and secondly due to the growing interest for minimal invasive diagnostic and therapeutic procedures in modern neurosurgery. Until now thecaloscopy was performed by the ISGT (International Study Group for Thecaloscopy) using co-axial downward orientated approaches. We have examined transsacral approaches to facilitate the navigation of flexible scopes in the lumbosacral subarachnoid space, and thus we now introduce further recognizable endoscopic anatomic landmarks.

Purpose: We have already dealt with the technical and anatomical basics for thecaloscopy. The first results of clinical application are presented and the indications for its diagnostic and therapeutic use are described. The aetiology of aseptic arachnitis and the term "Wide spinal canal syndrome" are discussed., Patients and Methods: Twelve patients who fulfilled the criteria for entry to the study were selected and the criteria were chosen according to German medical and legal rules. All patients underwent an endoscopic inspection and, if necessary, therapeutic manipulation under general anaesthesia., Results: In all cases the procedure was safely and successfully performed. The pathomorphology of the arachnoid was detected and endoscopically treated in almost all cases. Arachnoid cysts were successfully fenestrated and an intraspinal meningocoele treated with endoscopic assistance., Conclusion: Thecaloscopy is a safe procedure if skilfully performed. It provides an opening for a wide range of new diagnostic and therapeutic options.

Endoscopic anatomy differs from microsurgical anatomy. Topographical orientation as well as the proportion of objects, is different as they depend on the lens/object distance. Orientation under endoscopic conditions requires structures with defined positions or recognisable structures previously identified radiolologically. Structures are anatomical landmarks if the topographical relation to their surroundings is constant and they are easy and reliable to recognise. The contents of the dural sack are nerve roots with their supplying vessels, arachnoid trabeculars, filum terminale, and CSF. Safe navigation of a thecaloscope in relation to the bony structures is only possible with the simultaneous use of intraoperative fluoroscopy. To facilitate the navigation of scopes and instruments in the subarachnoid space we attempted to identify and describe reliable, and therefore constant recognisable anatomical landmarks.