The role of allelopathy in agricultural pest management.

Allelopathy is a naturally occurring ecological phenomenon of interference among organisms that may be employed for managing weeds, insect pests and diseases in field crops. In field crops, allelopathy can be used following rotation, using cover crops, mulching and plant extracts for natural pest management. Application of allelopathic plant extracts can effectively control weeds and insect pests. However, mixtures of allelopathic water extracts are more effective than the application of single-plant extract in this regard. Combined application of allelopathic extract and reduced herbicide dose (up to half the standard dose) give as much weed control as the standard herbicide dose in several field crops. Lower doses of herbicides may help to reduce the development of herbicide resistance in weed ecotypes. Allelopathy thus offers an attractive environmentally friendly alternative to pesticides in agricultural pest management. In this review, application of allelopathy for natural pest management, particularly in small-farm intensive agricultural systems, is discussed.

A 75% reduction in herbicide use through integration with sorghum + sunflower extracts for weed management in wheat.

BACKGROUND: To reduce herbicide use by 75%, integrated use of sorghum and sunflower extracts each at 18 L ha(-1) combined with 1/4(th) (75% less) of label rates of four herbicides (mesosulfuron + idosulfuron, metribuzin, phenoxaprop-p-ethyl and isoproturon) were investigated for the management of wild oat and canary grass, the two pernicious weeds in wheat fields worldwide. RESULTS: The results revealed that sorghum + sunflower extracts combined with 1/4(th) (75% less) of label rates of herbicides inhibited dry matter production of wild oat by up to 89% and canary grass by up to 92%. The wild oat and canary grass persistence index in sorghum + sunflower extracts combined with 1/4(th) (75% less) of label rates of herbicides was either lower or equal to respective label rates of herbicides, except sorghum + sunflower extract + 1/4(th) phenoxaprop-p-ethyl. Lower herbicide rates + water extracts also produced wheat grain yield statistically equal with label rates of respective herbicides. Two treatments having water extracts + lower herbicides rates were economical and sorghum + sunflower + 1/4(th) mesosulfuron + idosulfuron produced the highest (4404%) marginal rate of return. CONCLUSION: Herbicides use can be reduced by 75% through integration with sorghum + sunflower extracts without compromising yield and net benefits for cost-effective and eco-friendly management of wild oat and canary grass in wheat.

Cerebral venous thrombosis: analysis of a multicenter cohort from the United States.

OBJECTIVE: The data regarding diagnosis, prognosis, management, and outcome of patients with cerebral venous thrombosis are limited from the United States. METHODS: Patients with diagnosis of cerebral venous thrombosis were identified by International Classification of Diseases, Ninth Revision coding system at 10 centers in the United States during a 10-year period by retrospective chart review (1991-1997) or prospective enrollment (1997-2001). In all, 232 patients were screened for study inclusion and 182 of these patients were included in the study. RESULTS: The age range was 13 to 82 years (mean 38 years). Hypercoagulable state was the most common predisposing factor followed by pregnancy, malignancy, and homocystinemia. Neurologic examination revealed normal findings in 69 patients (38%); 37 (20%) were comatose, 59 (32%) had papilledema, and 71 (39%) had hemiparesis. In all, 61 patients (33%) had evidence of hemorrhage by computed tomography/magnetic resonance imaging. A total of 27 patients (15%) were treated with thrombolysis and 124 (68%) with anticoagulation. Overall mortality was 13% (n = 24). One-year follow up was available for 96 patients (53%). Of these, 26 (27%) were healthy, 43 (45%) were ambulatory with assistance, and 27 (28%) were still bedridden. On multivariate analysis, the best predictors of a poor outcome were coma at presentation (odds ratio 15.2 [95% confidence interval; 1.5-66]) and intracerebral hemorrhage (odds ratio 8.7 [95% confidence interval; 1.3-34.5]). CONCLUSION: Clinical and radiologic presentation of cerebral venous thrombosis in the United States is not much different from other parts of world but spectrum and frequency of predisposing factors are different. Number of patients treated with thrombolysis is higher as compared with other reported series of such patients. Coma at presentation and intracerebral hemorrhage were the strongest predictors of poor outcome, which is comparable with other series.

Neuromuscular Highlights-AAN 2005.

Summary of Neuromuscular Presentations at the 57 Annual AAN 2005 meeting in Miami Florida on topics of Facioscapulohumeral muscular dystrophy (FSHD), Duchenne muscular dystrophy (DMD), Diabetic Neuropathy, Charco Marie Tooth disease (CMT), Comparison of injected steroids versus Surgery for carpal tunnel syndrome, Rituximab in Anti-MAG associated polyneuropathy, Cannabis based medicine (CBM) in the treatment of neuropathic pain, utility of skin biopsy with intraepidermal nerve fiber density (IENFD) in sensory complaints, comparing sympathetic skin responses (SSRs) and skin biopsy in diagnosing small fiber sensory neuropathy, Chronic inflammatory demyelinating polyneuropathy (CIDP) clinical and electrophysiologic predictors, affect of limb warming in mild ulnar nerve conduction study (NCS) abnormalities, Tamoxifen affect in ALS, open label study of 3,4 DAP, Pyridostigmine and Ephedrine in fast channel syndrome, Mexilitine as an antimyotonia treatment in myotonic dystrophy (DM1), frontal lobe impairment evaluation in DM1 and DM2 patients and phenotype-genotype correlation in patients with dysferlinopathy.

Diffusion-weighted magnetic resonance imaging in superior sagittal sinus thrombosis.

BACKGROUND AND PURPOSE: Diffusion-weighted imaging (DWI) has shown high sensitivity in the diagnosis of acute arterial strokes. The pathophysiology of cerebral venous thrombosis with associated venous stroke appears to differ from that of arterial strokes. The purpose of this study was to describe DWI findings in venous strokes. METHODS: The authors reviewed 3 adults with superior sagittal sinus thrombosis who underwent DWI and magnetic resonance imaging within 24 hours of symptom onset. DWI was obtained at 1.5 T using the multishot echo planar technique (TR = 8000, TE = 97, field of view = 30 x 19 cm, slice thickness = 6.0 mm, interslice gap = 0.5 mm, matrix 128 x 128, NEX = 1). The diffusion gradients were applied in 3 orthogonal directions with 3 increasing b values (0-1000 s/mm2) to create average (trace) DWI images. Apparent diffusion coefficient (ADC) values were calculated on a pixel-by-pixel basis and displayed as ADC maps. RESULTS: DWI showed hyperintensities in patients 1 and 2 and hypointensity in patient 3 in corresponding to parenchymal lesions on conventional images. As compared to the homologous uninvolved location in the contralateral hemisphere, ADC values were decreased (0.53 x 10(-3) mm2/s [patient 1] and 0.68 x 10(-3) mm2/s [patient 2]) and increased (1.1 x 10(-3) mm2/s [patient 3]). The ADC ratio of the lesion in the involved to uninvolved side was 88% (patient 1), 81% (patient 2), and 120% (patient 3). CONCLUSION: Acute cerebral venous strokes may contain cytotoxic edema and/or vasogenic edema on DWI scans. DWI may be helpful in diagnosing cerebral venous thrombosis in cases with cryptic presentations.