Reduced herbicide antagonism through novel spray application techniques

Field studies were conducted to test three application methods for applying antagonistic herbicide combinations: 1) tank mix (TMX), 2) mix-in-line (MIL), and 3) separate boom (SPB). Sethoxydim applied with bentazon, glyphosate applied with dicamba or 2,4-D, and clethodim applied with dicamba or 2,4-D had higher efficacy when applied using the SPB method. Antagonism of all the herbicide combinations above was observed when applied using the TMX and MIL methods. In some cases, antagonism was avoided when using the SPB method. Three application methods tested in greenhouse studies were 1) TMX, 2) synthetic auxin applied first (AAF), and 3) synthetic auxin applied second (AAS). The AAS application method resulted in higher weed control than the TMX and AAF methods. Analysis done through liquid chromatography mass spectrometry supported the greenhouse results with higher rates of glyphosate detected with the AAS method

Perceived efficacy of herbal remedies by users accessing primary healthcare in Trinidad

BACKGROUND: The increasing global popularity of herbal remedies requires further investigation to determine the probable factors driving this burgeoning phenomenon. We propose that the users' perception of efficacy is an important factor and assessed the perceived efficacy of herbal remedies by users accessing primary health facilities throughout Trinidad. Additionally, we determined how these users rated herbal remedies compared to conventional allopathic medicines as being less, equally or more efficacious. METHODS: A descriptive cross-sectional study was undertaken at 16 randomly selected primary healthcare facilities throughout Trinidad during June-August 2005. A de novo, pilot-tested questionnaire was interviewer-administered to confirmed herbal users (previous or current). Stepwise multiple regression analysis was done to determine the influence of predictor variables on perceived efficacy and comparative efficacy with conventional medicines. RESULTS: 265 herbal users entered the study and cited over 100 herbs for the promotion of health/wellness and the management of specific health concerns. Garlic was the most popular herb (in 48.3% of the sample) and was used for the common cold, cough, fever, as 'blood cleansers' and carminatives. It was also used in 20% of hypertension patients. 230 users (86.8%) indicated that herbs were efficacious and perceived that they had equal or greater efficacy than conventional allopathic medicines. Gender, ethnicity, income and years of formal education did not influence patients' perception of herb efficacy; however, age did (p = 0.036). Concomitant use of herbs and allopathic medicines was relatively high at 30%; and most users did not inform their attending physician. CONCLUSION: Most users perceived that herbs were efficacious, and in some instances, more efficacious than conventional medicines. We suggest that this perception may be a major contributing factor influencing the sustained and increasing popularity of herbs. Evidence-based research in the form of randomized controlled clinical trials should direct the proper use of herbs to validate (or otherwise) efficacy and determine safety. In the Caribbean, most indigenous herbs are not well investigated and this points to the urgent need for biomedical investigations to assess the safety profile and efficacy of our popular medicinal herbs

Cholera Toxin B Subunits Assemble into Pentamers - Proposition of a Fly-Casting Mechanism

The cholera toxin B pentamer (CtxB5), which belongs to the AB5 toxin family, is used as a model study for protein assembly. The effect of the pH on the reassembly of the toxin was investigated using immunochemical, electrophoretic and spectroscopic methods. Three pH-dependent steps were identified during the toxin reassembly: (i) acquisition of a fully assembly-competent fold by the CtxB monomer, (ii) association of CtxB monomer into oligomers, (iii) acquisition of the native fold by the CtxB pentamer. The results show that CtxB5 and the related heat labile enterotoxin LTB5 have distinct mechanisms of assembly despite sharing high sequence identity (84%) and almost identical atomic structures. The difference can be pinpointed to four histidines which are spread along the protein sequence and may act together. Thus, most of the toxin B amino acids appear negligible for the assembly, raising the possibility that assembly is driven by a small network of amino acids instead of involving all of them

Practice Gap in Atrial Fibrillation Oral Anticoagulation Prescribing at Emergency Department Home Discharge

Introduction: Current U.S. cardiology guidelines recommend oral anticoagulation (OAC) to reduce stroke risk in selected patients with atrial fibrillation (AF), but no formal AF OAC recommendations exist to guide emergency medicine clinicians in the acute care setting. We sought to characterize emergency department (ED) OAC prescribing practices after an ED AF diagnosis. Methods: This retrospective study included index visits for OAC-naive patients ≥18 years old who were discharged home from the ED at an urban, academic, tertiary hospital with a primary diagnosis of AF from 2012-2014. Five hypothesis-blinded, chart reviewers abstracted data from patient problem lists and medical history in the electronic health record to assess stroke (CHA2DS2-VASc) and bleeding risk (HAS-BLED). The primary outcome was the provision of an OAC prescription at discharge in OAC-naive patients with high stroke risk. Descriptive statistics and multivariable logistic regression assessed associations between OAC prescription and patient characteristics. Results: We included 138 patient visits in our analysis, of whom 39.9% (n = 55) were low stroke risk (CHA2DS2-VASc = 0 in males and 1 in females), 15.9% (n = 22) were intermediate risk (CHA2DS2-VASc = 1 in males), and 44.2% (n = 61) were high risk (CHA2DS2-VASc ≥ 2). Of patients with high stroke risk and low-to-intermediate bleeding risk (n = 57), 80.7% were not prescribed an OAC at discharge. Cardiology consultation and female gender, but not stroke risk (CHA2DS2-VASc score), were predictors of an ED provider prescribing an OAC to an OAC-naive AF patient at ED discharge. Conclusion: The majority of OAC-eligible patients were discharged home without an OAC prescription. In OAC-naive patients discharged home from the ED, cardiology consultation and female gender were associated with OAC prescription. Our findings suggest that access to expert opinion may improve provider comfort with OAC prescribing and highlight the need for improved guidelines specific to ED-management of AF. [West J Emerg Med. 2020;21(4)924–934.

Reduced Herbicide Antagonism of Grass Weed Control through Spray Application Technique

Dicamba and 2,4-D tolerance traits were introduced to soybean and cotton, allowing for over the top applications of these herbicides. Avoiding antagonism of glyphosate and clethodim by dicamba or 2,4-D is necessary to achieve optimum weed control. Three field studies were conducted in fallow fields with broadleaf signalgrass (Urochloa platyphylla) and Italian ryegrass (Lolium perenne ssp. multiflorum) pressure. A tractor-mounted dual boom sprayer was modified to spray one of three application methods: (1) two herbicides tanked-mixed (TMX); (2) two herbicides in separate tanks mixed in the boom line (MIL); and (3) two herbicides in separate tanks applied through separate booms simultaneously (SPB). One study compared the three application methods with sethoxydim applied with bentazon, the second compared clethodim applied with dicamba or 2,4-D, and the third compared glyphosate applied with dicamba or 2,4-D. In most cases over all three trials, there was a 7–15% increase in efficacy when using the SPB application method. Antagonism of all the herbicide combinations above was observed when applied using the TMX and MIL methods. In some cases, antagonism was avoided when using the SPB method. The separate boom application method increased efficacy, which allowed herbicides to be used more effectively, resulting in improved economic and environmental sustainability of herbicide applications

The neuropathic potential of anti-GM1 autoantibodies is regulated by the local glycolipid environment in mice

Anti-GM1 ganglioside autoantibodies are used as diagnostic markers for motor axonal peripheral neuropathies and are believed to be the primary mediators of such diseases. However, their ability to bind and exert pathogenic effects at neuronal membranes is highly inconsistent. Using human and mouse monoclonal anti-GM1 antibodies to probe the GM1-rich motor nerve terminal membrane in mice, we here show that the antigenic oligosaccharide of GM1 in the live plasma membrane is cryptic, hidden on surface domains that become buried for a proportion of anti-GM1 antibodies due to a masking effect of neighboring gangliosides. The cryptic GM1 binding domain was exposed by sialidase treatment that liberated sialic acid from masking gangliosides including GD1a or by disruption of the live membrane by freezing or fixation. This cryptic behavior was also recapitulated in solid-phase immunoassays. These data show that certain anti-GM1 antibodies exert potent complement activation-mediated neuropathogenic effects, including morphological damage at living terminal motor axons, leading to a block of synaptic transmission. This occurred only when GM1 was topologically available for antibody binding, but not when GM1 was cryptic. This revised understanding of the complexities in ganglioside membrane topology provides a mechanistic account for wide variations in the neuropathic potential of anti-GM1 antibodies