INTEGRATED WEED CONTROL IN MAIZE.

Integrated pest management has been implemented as a general practice by EU legislation. As weed control actually is the most important crop protection measure in maize for Western Europe, the new legislation will have its impact. The question is of course which systems can be successfully implemented in practice with respect to labour efficiency and economical parameters. During 3 successive growing seasons (2007, 2008, 2009) weed control in maize was evaluated, the main focus was put on different techniques of integrated weed control and was compared with chemical weed control. Additionally, during 4 successive growing seasons (2011, 2012, 2013 and 2014) two objects based on integrated weed control and two objects based on mechanical weed control were compared to about twenty different objects of conventional chemical weed control. One of the objects based on mechanical weed control consisted of treatment with the flex-tine harrow before and after emergence in combination with chemical weed control at a reduced rate in 3-4 leave stage. The second one consisted of broadcast mechanical treatments before and after emergence followed by a final in-row application of herbicides and an inter-row cultivation at 6-7(8) leave stage. All trials were conducted on the Experimental farm of Bottelare HoGent-UGent on a sandy loam soil. Maize was growing in 1/3 crop rotation. The effect on weed growth as well as the economic impact of the different applications was evaluated. Combining chemical and mechanical weed control is a possible option in conventional farming but the disadvantages must be taken into account. A better planned weed control based on the real present weed-population in combination with a carefully thought-out choice of herbicides should also be considered as an IPM--approach.

WEED POPULATION IN RELATION TO CROP ROTATION AND NITROGEN FERTILISATION.

In order to assess the impact of crop rotation and nitrogen fertilisation in an agro system, a long-term field experiment has been established in 2006 at the experimental farm of Ghent University and University College Ghent (Bottelare-Belgium). The trial comprises 11 different crop rotations in combination with four nitrogen fertilizer regimes. The different crop rotations are monoculture of grain- and silage maize, whether or not followed by Italian ryegrass, permanent and temporary grass-clover and six other rotations of maize in combination with potatoes, wheat, fodder beet and peas. Normal crop husbandry measures were taken for each crop. The experiment was set up on a sandy loam soil, according to a strip plot design with 3 replicates. In the course of the experiment, crop rotation was the horizontal factor and fertilizer nitrogen (N) the vertical factor. The effect of crop rotation on yield, disease pressure, soil structure and earthworm abundance were evaluated yearly. In autumn 2013 the weed seed bank was analysed for each plot using the seedling emergence method. The obtained results indicated differences between the different crop rotations.

Chemical weed control in triticale (x Triticosecale Wittmack): review of five years of field experiments.

During five subsequent growing seasons field experiments were carried out at the experimental farm of the University College Ghent (Belgium) to evaluate the selectivity and efficacy of herbicides for chemical weed control in triticale (x Triticosecale Wittmack). The experiments were set up on a sandy loam soil, according to a completely randomised block design with four replicates. Several herbicides and combinations of herbicides were applied pre- and post-emergence, at different rates. The influence of the different treatments on weed diversity, weed density, growth inhibition and chlorosis of the crop and grain yield was studied. Results obtained from these field trials indicated differences between the different treatments.

Monounsaturated fat-rich diet prevents central body fat distribution and decreases postprandial adiponectin expression induced by a carbohydrate-rich diet in insulin-resistant subjects.

OBJECTIVE: Central obesity is associated with insulin resistance through factors that are not fully understood. We studied the effects of three different isocaloric diets on body fat distribution, insulin sensitivity, and peripheral adiponectin gene expression. RESEARCH DESIGN AND METHODS: Eleven volunteers, offspring of obese type 2 diabetic patients with abdominal fat deposition, were studied. These subjects were considered insulin resistant as indicated by Matsuda index values <4 after an oral glucose tolerance test, and they maintained A1C <6.5% without therapeutic intervention. All subjects underwent three dietary periods of 28 days each in a crossover design: 1) diet enriched in saturated fat (SAT), 2) diet rich in monounsaturated fat (MUFA) (Mediterranean diet), and 3) diet rich in carbohydrates (CHOs). RESULTS: Weight, body composition, and resting energy expenditure remained unchanged during the three sequential dietary periods. Using dual-energy X-ray absorptiometry we observed that when patients were fed a CHO-enriched diet, their fat mass was redistributed toward the abdominal depot, whereas periphery fat accumulation decreased compared with isocaloric MUFA-rich and high-SAT diets (ANOVA P < 0.05). Changes in fat deposition were associated with decreased postprandial mRNA adiponectin levels in peripheral adipose tissue and lower insulin sensitivity index values from a frequently sampled insulin-assisted intravenous glucose tolerance test in patients fed a CHO-rich diet compared with a MUFA-rich diet (ANOVA P < 0.05). CONCLUSIONS: An isocaloric MUFA-rich diet prevents central fat redistribution and the postprandial decrease in peripheral adiponectin gene expression and insulin resistance induced by a CHO-rich diet in insulin-resistant subjects.

Possibilities of chemical weed control in Lupinus albus and Lupinus luteus-screening of herbicides.

Weed control in sweet lupins is still a problem. Especially the phytotoxicity of herbicides in sweet lupins is not enough studied. Therefore a screening with 16 selected herbicides and 4 lupin varieties has been set up. During the growing season 2005, 10 of the tested herbicides were applied in pre-emergence, 6 in post-emergence. Pre-emergence: Most of the active matters tested in pre-emergence were not phytotoxic for lupins. Pendimethalin (1000 g/ha), linuron (500 g/ha), chlorotoluron (1500 g/ha), prosulfocarb (2400 g/ha), clomazone (72 g/ha), isoxaben (100 g/ha), metamitron (1050 g/ha) and dimethenamid-P (720 g/ha) were applied without causing any significant phytotoxic symptoms. Only the lupins treated with aclonifen (1200 g/ha) showed a significant growth inhibition, 3 weeks after treatment. Significantly more chlorosis was noticed when the lupins were treated with aclonifen or with diflufenican, in preemergence. Post-emergence: In post-emergence, diflufenican (50 g/ha) did not cause any crop damage. Florasulam (5 g/ha) caused almost 100% necrosis in L. albus as well as in L. luteus. Bentazon (652 g/ha), thifensulfuron-methyl (15 g/ha) and metribuzin (175 g/ha) caused obvious necrosis and growth inhibition of the crop. The growth inhibition was significantly more severe for lupins treated with bentazon than if they were treated with thifensulfuron-methyl or metribuzin. Three weeks after treatment, clomazone (90 g/ha) and diflufenican (50 g/ha), did not cause any crop injury at all. The results indicated an interesting range of active matters which can be applied in pre-emergence, but weed control in post-emergence stays difficult.

Effect of different chemical and mechanical defolation methods on the skin quality of potatoes.

Without foliage destruction an efficient harvest is impossible. Potatoes for the fresh market are often harvested when the foliage is still heavy green due to tuber size and starch content that must be limited. Tubers from immature vines are typically very susceptible to skinning and mechanical injury during harvest. Young tubers from immature vines need more time after foliage destruction to set periderm than tubers from senescent vines where the formation of periderm is already started. Spray schemes based on metoxuron, carfentrazone-ethyl and diquat at a dose of 300 g/ha caused slower leaf and stem desiccation. Over the 3 growing seasons it could be concluded that mechanical foliage destruction in combination with carfentrazone-ethyl + mineral oil promoted periderm formation better than the other desiccation schemes tested. A split treatment with diquat at 300 g/ha or carfentrazone-ehtyl + mineral oil followed by a second application of diquat or carfentrazone-ethyl can led to a slower periderm formation and even give secondary growth. A double treatment of diquat (300 g/ha) or carfentrazone-ethyl + mineral oil followed by diquat (600 g/ha) after 3 days gave satisfactory results. Rhizoctonia tuber infection increased with a longer field period after treatment. In general the increase was more pronounced for the spray schemes where skin set of the tubers was less fast.

[Level of S-100 and neuron-specific enolase in cerebrospinal fluid from subjects with neurological pathologies]. / Niveles de S-100 y enolasa neuroespecífica en líquido cefalorraquídeo de enfermos con patología neurológica.

AIM: To evaluate S-100 and neuro specific enolase (NSE) levels in cerebrospinal fluid (CSF) from patients with differents neurological disorders in order to study possible differences in their protein concentrations. MATERIAL AND METHODS: We analysed samples of CSF taked by spinal puncture in subjects either from of the Casualty Department or from the Department of Neurology. Patients displaying neurological symptoms capable of being diagnostically tested. The total number of patients-samples examined was 43 (23 males and 20 females; mean age 43 y, range 1-78 y). Five patients groups were studied: a control group, meningitis, dementia, polyneuropathy-motorneuron disease, and acute cerebral infarction group (ACV). S-100 and NSE concentrations were measured by immunoradiometric procedures. RESULTS: Highest S-100 median levels in CSF were found in dementia and ACV group, with elevate concentrations in meningitis groups. The increased S-100 levels in these groups was significant compared with control group (Mann-Withney U test). For NSE concentrations, there is a significant differences between dementia group and control group. No other significant differences were found between groups. There were positive correlation between S-100 levels and total protein. CONCLUSION: Our results suggest that S-100 and NSE can be a sensitive marker of brain damage in different neurological disorders. However, levels must be considered individually, since these concentrations depend on several factors, such as age, severity of brain damage or interval between the onset of brain damage and the taking of the sample.

Cerebrospinal fluid S-100 protein levels in neurological pathologies.

The aim of this paper was to evaluate S-100 concentration in cerebrospinal fluid (CSF) from patients with different neurological disorders, and in subjects with no proven neurological pathology, in order to study possible differences in their protein concentrations. The total number of patient-samples examined was 119 (58 males and 61 females; mean age 35 yrs, 1-79 yrs). Based on the final diagnoses, nine patient groups were studied: a control group, meningitis, acute lymphatic leukemia (ALL), dementia, hydrocephalia, polyneuropathy-motor neuron disease, acute cerebral infarction (ACI), and patients diagnosed with multiple sclerosis. S-100 protein concentrations were measured by the Sangtec 100 two-site immunoradiometric assay. The highest S-100 levels in CSF were found in the dementia group, ACI group, bacterial-fungal and lymphocytic meningitis groups (Kruskal-Wallis test). The S-100 concentrations in these groups were significantly higher compared with the control group (Mann-Whitney U test, p<0.05, p<0.01) and the multiple sclerosis group (p<0.05, p<0.01). No other significant differences were found between groups. Our results suggest that the high protein levels in CSF found in these pathologies may reflect the presence of brain damage. However, the levels need to be considered individually, as they depend on several factors, such as age, severity of brain damage or interval between the onset of brain damage and the taking of the sample.

[Pulmonary activity in sarcoidosis: 67Ga uptake quantification and plasma determination of 1,25-dihydroxyvitamin D)]. / Actividad pulmonar en sarcoidosis: cuantificación de la captación de 67Ga y determinación plasmática de 1,25-dihidroxivitamina D.

AIM: The aim of our study was to produce a quantitative determination of Ga-67 pulmonary intake and correlate it with plasma levels of calcitriol. MATERIAL AND METHODS: A prospective study was conducted, and included 65 patients (29 female, 36 male) referred to our section due to suspected sarcoidosis or fibrosis of the lungs. Gammagraphic images were obtained after injecting Ga-67 citrate, and vitamin D was determined by IRMA method. The final diagnosis led to 4 groups of patients: 26 with active sarcoidosis; 5 with inactive sarcoidosis (4 with a previous gammagraphic study, included in the previous group); 8 with fibrosis of the lungs; and 30 patients with no demonstrable pathology following medical/instrumental examination. For the quantitative analysis, areas of interest were drawn around each lung, together with another region in soft tissue of the right shoulder (background). The geometric mean for each region was calculated, as well as the Ga intake rate (InGa = [lung activity-background]/background). RESULTS: Significant differences were found (p<0.01) when comparing each group's InGa, with the highest values occurring in the active sarcoidosis group. No significant differences were found when comparing plasma levels of calcitriol. No significant correlation was demonstrated between hormone and InGa rates. CONCLUSIONS: InGa would seem to be a useful parameter for assessing inflammatory activity in the parenchyma of the lungs. Perhaps as a result of their variability, plasma concentrations of the active vitamin D metabolite have a limited role in this assessment.

[Effect of different observers on the interpretation of pulmonary perfusion scintigraphy]. / Influencia de diferentes observadores sobre la interpretación de la gammagrafía de perfusión pulmonar.

AIM: The agreement in the interpretation of the scintigraphic images of pulmonary perfusion in the diagnosis of pulmonary tromboembolism (TEP) is not always the most adequate. The purpose of this study was to evaluate the degree of agreement by eight observers in the interpretation of these studies. MATERIAL AND METHODS: The study population consisted of 180 studies with clinically suspected pulmonary embolism referred to our department for scintigraphic perfusion imaging from April 98 to September 99. The patients received an intravenous injection of 111-148 MBq (3-4 mCi) of 99mTc-macroaggregated albumin whereas the images were obtained in the six routine projections. The observers consisted of five nuclear medicine physicians and three residents who independently reviewed the scintigrams (low, intermediate and high probability). In a second step, the physicians performed consensus interpretations. The Kappa statistics was used to evaluate the degree of agreement between individual observer interpretations beyond that expected by chance alone. RESULTS: The mean value SEM for Kappa index was 0.58 0.02, with maximum and minimum values of 0.76 and 0.27 respectively. The interobserver variability was greater than expected. Except in two observers scans in the interpretation of images in the low and high categories showed minor discrepancies, whereas scans in intermediate probability showed the most important interobserver variations. CONCLUSION: The study manifests the importance of a uniform criteria in lung scintigraphic interpretation.

[Tomographic studies of myocardial perfusion normality with 99m Tc-Tetrofosmin. Spanish multicenter study]. / Estudios tomográficos de normalidad de perfusión miocárdica con 99mTc-Tetrofosmina. Estudio multicéntrico español (I). Aspectos técnicos: diseño del estudio y control de calidad.

As a first phase in a nationwide multicenter study to obtain myocardial perfusion normality patterns, this work presents the study design and quality control methodology used to guarantee that the gammacameras fulfilled some minimum quality requirements. The following aspects were considered in the study design in order to guarantee the homogeneity and interchangeability of the results: creation and structure of the work group, data interchange system, data selection and acquisition, centralized archiving and processing, assessment system, study acceptance criteria and distribution of the results. To carry out the instrumental quality control, three phantom studies were established, one to control the rotation center, another to verify tomographic uniformity and a third to simulate the shape and orientation of the left ventricle. The three phantoms circulated through all of the 18 participating centers in this project, which corresponded to 19 gammacameras. Very strict guidelines had to be followed in the acquisition and processing of these phantom studies. If any camera and/or center did not fulfill the criteria established, it was advised of the problem detected in order to correct it. Once the defect was repaired, all the phantoms were sent again for verification. Uniformity of the rotation center was quantified by means of the eccentricity of a 360 degrees orbit, admitting up to a maximum of 10%. Tomographic uniformity was visually assessed, taking in account the number of slices with rings and their contrast and finally no artifacts could be present in the reconstructed study of the ventricle. The center of rotation was within limits in all the cameras except one case while the tomographic uniformity was incorrect in 6 cases. All the departments, except one, corrected the defects detected, and passed the acceptance test. The results made it possible to guarantee adequate homogeneity and instrumental quality in this multicenter study.

Catecholamine levels in practitioners of the transcendental meditation technique.

With the aim of evaluating the sympathetic-adrenal medulla system in subjects practicing transcendental meditation (TM), their plasma catecholamine levels were determined at two different times of day. The study group consisted of 19 subjects who regularly practice either TM or Sidhi-TM technique, with a control group made up of 16 healthy subjects who had not previously used any relaxation technique. Catecholamine plasma levels were determined by high performance liquid chromatography, at 0900 and 2000 h. Morning and evening norepinephrine (NE) levels and morning epinephrine (E) levels were significantly lower in the TM group than in the control subjects (morning NE levels, pg/ml, mean+/-S.E.: TM group 136.6+/-13.0, control 236.8+/-21.0, P=.0001; evening NE levels: TM group 119.7+/-10.8, control 175.6+/-17.4, P=.009; morning E levels, pg/ml: TM group 140.2+/-10.6, control 196.7+/-23.8, P=.019). No differences were recorded for evening E levels and dopamine (DA) levels. No significant differences were found for catecholamine levels measured at different times of day in the TM group, demonstrating a lack of daily hormonal rhythm. Anxiety levels were similar in both groups. Based on the results obtained, it can be considered that the regular practice of TM has a significant effect on the sympathetic-adrenal medulla system. A low hormonal response to daily stress caused by sympathetic tone regulation through regular TM could explain our results, as well as the physiological and other effects related to the field of health described in those who practice meditation.

[Scintigraphic pattern in a case of Tarlov cyst]. / Patrón gammagráfico en un caso de quiste de Tarlov.

We report the case of a 40-year-old man remitted to our department with a history of lower back pain and sciatica with no history of trauma. The laboratory analyses showed normal values whereas plain radiographs showed a sacrum rarefaction area. A 99mTc-MDP bone scintigraphy was performed to evaluate the lumbosacral area. Planar images did not show any abnormality. SPECT images revealed photopenic abnormality in the second sacral vertebral right hemibody, with no peripherally increased radiotracer accumulation. Subsequent MRI and CT myelography demonstrated the nature of the photopenic area as secondary to vertebral erosion by sacral perineurial cyst (Tarlov cyst).

Evaluation of tumor marker S-100 in cerebrospinal fluid from subjects with nonischemic brain pathologies.

In order to evaluate the S-100 concentration in cerebrospinal fluid from subjects with nonischemic brain damage, a total of 33 samples were analyzed: 11 from subjects in whom no organic disease could be found; 14 from patients with a diagnosis of lymphocytic or bacterial-fungal meningitis, and 8 from patients with acute lymphatic leukemia but no demonstrable signs of meningeal involvement. In all cases, the subjects considered had no previous history of melanoma or ischemic brain damage. The mean levels +/- SEM found for each study group were 1.00 +/- 0.11, 1.67 +/- 0.23 and 1.17 +/- 0.14 microg/l, respectively. Significant differences appeared between the groups when applying the Kruskal-Wallis nonparametric test (p = 0.035). The highest levels were found in the meningitis group and were significantly different from those of the control group (p = 0.015). No significant differences were found with regard to age or sex. Based on the pathophysiology of meningitis and on previous studies, the results suggest the existence of brain damage caused by an infection as a possible cause of increased S-100 levels.

Repetitive nontreated episodes of grade 1B or 2 acute rejection impair long-term cardiac graft function.

BACKGROUND: Episodes of grade 1B or 2 acute heart rejection are usually not treated, and most of them resolve spontaneously. METHODS: With the aim to assess long-term outcome in patients with repetitive nontreated episodes of low-grade (1B, 2) acute rejection, we have studied 141 heart transplant recipients in whom the evolutive pattern of acute rejection during the first 6 months after transplantation could be determined. RESULTS: Forty-four patients (31%) had only grade 0 or 1A acute rejection episodes (pattern A); 23 patients (16%) had three or more episodes of grade 1B or 2 acute rejection without 3A or more advanced rejection (pattern B); 48 patients (34%) had one or two episodes of grade 3A, 3B, or 4 acute rejection only during the first 6 months after transplantation (pattern C); and 26 patients (19%) had three or more episodes of grade 3A, 3B, or 4 acute rejection (pattern D). Overall mortality was 11%, 26%, 19%, and 46% for patients with patterns A, B, C, and D, respectively. No difference was found among patterns with regard to incidence of graft atherosclerosis. Left ventricular ejection fraction at 1 year after transplantation was significantly lower (p < 0.05) for patients with pattern B (50% +/- 5% versus 59% +/- 7%, 59% +/- 11%, and 56% +/- 6% for patterns A, C, and D, respectively); cardiac index also was lower for patients with pattern B than for those with pattern A (3.6 +/- 0.6 versus 4.1 +/- 0.6 L/min/m2, p < 0.05). CONCLUSIONS: Although mortality was higher for patients with more severe episodes of acute rejection, only repetitive nontreated episodes of grade 1B or 2 rejection significantly impaired long-term graft function.

[Short- and long-term course of heart transplantation recipients with severe dysfunction of the graft associated with acute rejection]. / Evolución a corto y largo plazo de los pacientes sometidos a trasplante cardíaco con disfunción severa del injerto asociada a rechazo agudo.

INTRODUCTION AND OBJECTIVES: Acute rejection is still a common cause of death after heart transplantation, in spite of cyclosporine. The aim of our study was to assess the incidence of severe graft dysfunction associated with acute rejection and the short and long-term outcome of these patients. METHODS: Ten of our 100 first heart transplant patients have developed rejection-induced severe cardiac dysfunction (left ventricular ejection fraction determined by echocardiography < 35% associated with 3A, 3B or 4 acute rejection). Clinical outcome, complications and evolution of left ventricular function were studied. RESULTS: Five patients were given intravenous methylprednisolone 500 to 1000 mg/day for 3 days. The other 5 patients had severe heart failure and received antilymphocyte antibodies. Three patients treated with methylprednisolone alone and one patient treated with antilymphocyte antibodies died within the first week after therapy. Left ventricular ejection fraction increased from 26 +/- 4% to 51 +/- 6% at 1 month after therapy in the 6 survivor patients. Four of the 6 survivor patients also died before 1 year after rejection (3 due to infection). Thus, long-term, overall mortality was 80%. CONCLUSIONS: Although favorable short-term results can be achieved in patients with rejection-induced severe cardiac dysfunction with immunosuppressive therapy (mainly antilymphocyte antibodies), long-term prognosis seems poor, due to the increased rate of life-threatening infections.

Influence of heart transplantation on the natural history of patients with severe congestive heart failure.

In an attempt to study the influence of heart transplantation on the natural history of patients with severe congestive heart failure, we have reviewed our experience with 240 consecutive patients who were New York Heart Association class IV or III/IV, who had left ventricular ejection fraction less than 35%, who were younger than 65 years of age, and who were assessed for heart transplantation in our hospital since May 1986. Mean age was 47 +/- 12 years. Left ventricular ejection fraction was 20% +/- 6%. Eighty-seven percent were male. New York Heart Association class was IV in 88% and III/IV in 12%. The cause was ischemic heart disease in 35% of patients, valvular heart disease in 13% of patients, and primary dilated cardiomyopathy in 52% of patients. At initial assessment, heart transplantation was considered to be not indicated in 30% of patients, indicated in 51% of patients, and contraindicated in 19% of patients. During a follow-up of 13 +/- 13 months (2 to 64 months), 110 patients underwent transplantation (46%). Posttransplantation actuarial probability of survival was 70% at 3 years. Three-year probability of survival free from transplantation was significantly lower for patients older than 55 years of age (p < 0.05), for those with left ventricular ejection fraction less than 20% (p < 0.05), ischemic causes (p < 0.05), New York Heart Association class IV (p < 0.001), and indication/contraindication for transplantation (p < 0.001); no difference was noted for gender.(ABSTRACT TRUNCATED AT 250 WORDS)