The seed sector in Latvia

In each issue, European Seed shines the spotlight on one of the many national seed associations in Europe that are so crucial in representing the local seed sector at both the national and international levels, along sharing the sector's concerns with the government. Although seed and seed trade associations are present in many countries throughout the continent there is no such association in Latvia, so European Seed decided to look at several other factors that shape the seed sector environment in this country. Interviewing Roberts Stafeckis, Director of the Institute of Agricultural Resources and Economics (AREI)

Transferable Odor Differentiation Models for Infectious Disease Diagnostics

__Abstract__ In recent years the interest for the application of an electronic nose (eNose) in medical Diagnostics is increasing. There is a need for this since eNose Diagnostics is non-invasive, easy to run, fast and cheap. The eNoses, now on the market, however, turn out to be unsuitable for large-scale application. This is mainly due to insufficient reproducibility of measurement results. In this work an eNose is used which is cheap and suited for mass applications. The usage of advanced temperature control guarantees the reproducibility between eNoses. In practice, this means that a once developed analysis model for a specific disease easily can be transferred to any number of other eNoses. Application of mass-produced components keeps the cost low. In the research it is shown that temperature variation is the main cause of the significant differences in measurement characteristic between the metal oxide sensors on which the eNose is based. To illustrate the practical applicability pilot studies are described for sepsis (bacterial infection of the blood), tuberculosis (TB) and metritis (infection of the uterus in cows). In the sepsis and metritis studies the measurements were conducted in the headspace of the blood cultures and uterus mucus respectively. In the tuberculosis study the exhaled breath of patients analyzed. For the sepsis diagnostics 30 eNoses are used to identify 11 to identify clinical relevant pathogens in blood. The eNose can significantly speed up the diagnostic process: on average 78% of the pathogens were correctly identified within 6-8 hours after inoculation in contrast to the 24 hours typically needed with the current methods. The TB-study was conducted in Dhaka (Bangladesh) with 3 eNoses. It turned out to be possible to distinguish between healthy people and those with active TB infection [sensitivity 93.5%, specificity 85.3%] but also to identify an active TB infection in a group of TB suspects [sensitivity 76.5%, specificity 87.2%]. These results are significantly better than the much-used screening test based on microscopy. Currently there is no objective diagnosis for metritis. A vet performs the diagnosis based on a number of characteristics such as temperature and appearance of the sample. The eNose proved to be more reliable and objective than a control panel of veterinarians [sensitivity 100%, specificity 91.6%]

Laparoscopic ileocolic resection versus infliximab treatment of distal ileitis in Crohn's disease: a randomized multicenter trial (LIR!C-trial)

Contains fulltext : 69534.pdf (publisher's version ) (Open Access)BACKGROUND: With the availability of infliximab, nowadays recurrent Crohn's disease, defined as disease refractory to immunomodulatory agents that has been treated with steroids, is generally treated with infliximab. Infliximab is an effective but expensive treatment and once started it is unclear when therapy can be discontinued. Surgical resection has been the golden standard in recurrent Crohn's disease. Laparoscopic ileocolic resection proved to be safe and is characterized by a quick symptom reduction.The objective of this study is to compare infliximab treatment with laparoscopic ileocolic resection in patients with recurrent Crohn's disease of the distal ileum with respect to quality of life and costs. METHODS/DESIGN: The study is designed as a multicenter randomized clinical trial including patients with Crohn's disease located in the terminal ileum that require infliximab treatment following recent consensus statements on inflammatory bowel disease treatment: moderate to severe disease activity in patients that fail to respond to steroid therapy or immunomodulatory therapy. Patients will be randomized to receive either infliximab or undergo a laparoscopic ileocolic resection. Primary outcomes are quality of life and costs. Secondary outcomes are hospital stay, early and late morbidity, sick leave and surgical recurrence. In order to detect an effect size of 0.5 on the Inflammatory Bowel Disease Questionnaire at a 5% two sided significance level with a power of 80%, a sample size of 65 patients per treatment group can be calculated. An economic evaluation will be performed by assessing the marginal direct medical, non-medical and time costs and the costs per Quality Adjusted Life Year (QALY) will be calculated. For both treatment strategies a cost-utility ratio will be calculated. Patients will be included from December 2007. DISCUSSION: The LIR!C-trial is a randomized multicenter trial that will provide evidence whether infliximab treatment or surgery is the best treatment for recurrent distal ileitis in Crohn's disease. TRIAL REGISTRATION: Nederlands Trial Register NTR1150

Diagnosing viral and bacterial respiratory infections in acute COPD exacerbations by an electronic nose: a pilot study

Respiratory infections, viral or bacterial, are a common cause of acute exacerbations of chronic obstructive pulmonary disease (AECOPD). A rapid, point-of-care, and easy-to-use tool distinguishing viral and bacterial from other causes would be valuable in routine clinical care. An electronic nose (e-nose) could fit this profile but has never been tested in this setting before. In a single-center registered trial (NTR 4601) patients admitted with AECOPD were tested with the Aeonose (R) electronic nose, and a diagnosis of viral or bacterial infection was obtained by bacterial culture on sputa and viral PCR on nose swabs. A neural network with leave-10%-out cross-validation was used to assess the e-nose data. Forty three patients were included. In the bacterial infection model, 22 positive cases were tested versus the negatives; and similarly 18 positive cases were tested in the viral infection model. The Aeonose was able to distinguish between COPD-subjects suffering from a viral infection and COPD patients without infection, showing an area under the curve (AUC) of 0.74. Similarly, for bacterial infections, an AUC of 0.72 was obtained. The Aeonose e-nose yields promising results in 'smelling' the presence or absence of a viral or bacterial respiratory infection during an acute exacerbation of COPD. Validation of these results using a new and large cohort is required before introduction into clinical practice

Electrochemical oxidation of quaternary ammonium electrolytes:Unexpected side reactions in organic electrochemistry

Quaternary ammonium salts are among the most widely used electrolytes in organic electrochemistry, but there is little known about their unwanted side oxidation reactions. We have, therefore, studied the constant potential oxidation products of quaternary ammonium electrolytes using mass spectrometry, and the proposed oxidation reaction mechanisms were verified by stable isotope labeling studies. Oxidation of tetrabutylammonium at +2.5 V vs Ag showed oxidation products at m/z 256, 258, and 299 which were shown corresponding to alcohol, ketone, and acetonitrile-derived amide products, respectively. We propose a mechanism based on the anodic oxidation of the side chain, to generate a carbocation, followed by nucleophilic attack by water or acetonitrile. Incorporation of a water molecule and/or an acetonitrile molecule in the structure was verified by mass analysis of the isotopically labeled oxidation products. Oxidation can be avoided by use of quaternary ammonium ions with shorter alkyl chains, where electrostatic repulsion presumably prohibits carbocation generation. (C) 2012 Elsevier B.V. All rights reserved

Diagnosis of active tuberculosis by e-nose analysis of exhaled air

Tuberculosis (TB), a highly infectious airborne disease, remains a major global health problem. Many of the new diagnostic techniques are not suited for operation in the highly-endemic low-income countries. A sensitive, fast, easy-to-operate and low-cost method is urgently needed. We performed a Proof of Principle Study (30 participants) and a Validation Study (194 participants) to estimate the diagnostic accuracy of a sophisticated electronic nose (DiagNose, C-it BV) using exhaled air to detect tuberculosis. The DiagNose uses a measurement method that enables transfer of calibration models between devices thus eliminating the most common pitfall for large scale implementation of electronic noses in general. DiagNose measurements were validated using traditional sputum sm We found a sensitivity of 95.9% and specificity of 98.5% for the pilot study. In the validation study we found a sensitivity of 93.5% and a specificity of 85.3% discriminating healthy controls from TB patients, and a sensitivity of 76.5% and specificity of 87.2% when identifying TB patient within the entire test-population (best-case numbers). The portability and fast time-to-result of the DiagNose enables a proactive screening search for new TB cases in rural areas, without the need for highly-skilled operators or a hospital center infrastructure. (C) 2012 Elsevier Ltd. All rights reserved

Enabling a transferable calibration model for metal-oxide type electronic noses

While electronic noses have been around for over 30 years, little effort has been devoted to the development of transferable calibration models, which are models that can be applied to multiple equivalent devices without adjustment. The majority of published results limit itself to data sets gathered with a single device. This lack of insight in transferable models hampers large scale implementations of eNose-based applications as individual calibration of a multitude of devices for a specific application area is generally unrealistic due to the requirement of actual samples to be measured. For simple gases this may be do-able, but in the case of more complex samples such as biological patient material it is logistically impossible. In this paper we show the influence of the deviation of the sensor temperature on the measurement reproducibility and by inference on the transferability of calibration models. We introduce the total inertia (φ2) as a measure for the heterogeneity within the measured data. The total inertia is an objective measure known from linear algebra, where it is used to calculate the correspondence between matrices. We use 5 micro-hotplate metal-oxide sensors from the same wafer, with an inter-sensor heater temperature difference of approximately 15 C in combination with 2 substances, n-butyl-acetate and hexane. This research demonstrates the increase in heterogeneity of the measured response values in relation to a temperature shift. A shift of 15 C at the sensor surface causes an increase of heterogeneity that is 10-15 times higher than the increase in heterogeneity caused by inter-sensor responses to the substances when operated at exactly the same temperature. Some mixtures of substances will be separable by pattern recognition under virtually any condition, and strict temperature control will neither improve nor deteriorate results. However the significant contribution of temperature deviation toward data heterogeneity renders it plausible that optimized temperature control, and by inference lower data heterogeneity, is a prerequisite for transferability of a calibration model. This holds true when applied to metal-oxide sensors and for mixtures containing substances showing a fair degree of similarity