Mechanisms underpinning the permanent muscle damage induced by snake venom metalloprotease

Snakebite is a major neglected tropical health issue that affects over 5 million people worldwide resulting in around 1.8 million envenomations and 100,000 deaths each year. Snakebite envenomation also causes innumerable morbidities specifically loss of limbs as a result of excessive tissue/muscle damage. Snake venom metalloproteases (SVMPs) are a predominant component of viper venoms, and are involved in the degradation of basement membrane proteins (particularly collagen) surrounding the tissues around the bite site. Although their collagenolytic properties have been established, the molecular mechanisms through which SVMPs induce permanent muscle damage are poorly understood. Here, we demonstrate the purification and characterisation of an SVMP from a viper (Crotalus atrox) venom. Mass spectrometry analysis confirmed that this protein is most likely to be a group III metalloprotease (showing high similarity to VAP2A) and has been referred to as CAMP (Crotalus atrox metalloprotease). CAMP displays both collagenolytic and fibrinogenolytic activities and inhibits CRP-XL-induced platelet aggregation. To determine its effects on muscle damage, CAMP was administered into the tibialis anterior muscle of mice and its actions were compared with cardiotoxin I (a three-finger toxin) from an elapid snake (Naja pallida) venom. Extensive immunohistochemistry analyses revealed that CAMP significantly damages skeletal muscles by attacking the collagen scaffold and other important basement membrane proteins, and prevents their regeneration through disrupting the functions of satellite cells. In contrast, cardiotoxin I destroys skeletal muscle by damaging the plasma membrane, but does not impact regeneration due to its inability to affect the extracellular matrix. Overall, this study provides novel insights into the mechanisms through which SVMPs induce permanent muscle damage

Venomous snakebites: rapid action saves lives - a multifaceted community education programme increases awareness about snakes and snakebites among the rural population of Tamil Nadu, India

The lack of public awareness surrounding the dangers of snakebite envenomation (SBE) is one of the most critical factors contributing to SBE-induced complications, and subsequently exacerbating the number of deaths and disabilities resulting from SBE. In this study, we deployed a multifaceted community education programme to educate students, healthcare professionals and members of the public in rural areas of Tamil Nadu, India about the dangers of SBE, appropriate first aid measures and the ‘do’s and don’ts’ following a snakebite. An assessment of prior knowledge within these communities identified several misconceptions concerning snakes and SBE. Using a combination of direct engagement (estimated to reach over 200,000 people), information leaflets (200,000 distributed), posters, video documentaries, media and social media (>2.8 million engagements), over the course of one year (January to December 2019) we reached over 3 million people in rural Tamil Nadu (around 8% of population). Evaluation of community-based assemblies indicated that at least 90% of attendees were able to recall the key messages at the end of the events, and at least 85% were able to recall the key messages even after 12 months. Due to high demand, a one-day symposium was organised to provide clinical knowledge and training on SBE to 250 healthcare professionals in rural Tamil Nadu. Notably, an assessment of patient data (291 victims) collected from a snakebite referral hospital over the same 12-month period (2019) indicated that arrival time at hospital following a snakebite was significantly faster and the effective first aid measures were administered to patients who were aware of our activities compared to those that were not. Overall, our approach provides a framework on how to educate rural communities about the dangers of SBE and thereby, mitigate delayed SBE treatment leading to an overall reduction in SBE-induced mortality, morbidity, treatment costs and other socio-economic ramifications

Influence of spatial arrangement, biofertilizers and bioirrigation on the performance of legume-millet intercropping system in rainfed areas of southern India

In this study, we checked the potential of bioirrigation – defined as a process of hydraulic lift where transfer of water occurs from deep soil layers to top soil layers through plant roots. We tested this in a pigeon pea (PP) – finger millet (FM) intercropping system in a field study for two consecutive growing seasons (2016/17 and 2017/18) at two contrasting sites in Bengaluru and Kolli Hills, India. Our objective was also to optimize the spatial arrangement of the intercropped plants (2 PP:8 FM), using either a row-wise or a mosaic design. The field trial results clearly showed that spatial arrangement of component plants affected the yield in an intercropping system. The row-wise intercropping was more effective than mosaic treatments at the Bengaluru field site, while at Kolli Hills, both row-wise and mosaic treatment performed equally. Importantly, biofertilizer application enhanced the yield of intercropping and monoculture treatments. This effect was not influenced by the spatial arrangement of component plants and by the location of the field experiment. The yield advantage in intercropping was mainly due to the release of PP from interspecific competition. Despite a yield increase in intercropping treatments, we did not see a positive effect of intercropping or biofertilizer on water relations of FM, this further explains why PP dominated the competitive interaction, which resulted in yield advantage in intercropping. FM in intercropping had significantly lower leaf water potentials than in monoculture, likely due to strong interspecific competition for soil moisture in intercropping treatments. Our study indicates that identity plant species and spatial arrangement/density of neighbouring plant is essential for designing a bioirrigation based intercropping system

Effects of fluoxetine on functional outcomes after acute stroke (FOCUS): a pragmatic, double-blind, randomised, controlled trial

Background Results of small trials indicate that fluoxetine might improve functional outcomes after stroke. The FOCUS trial aimed to provide a precise estimate of these effects. Methods FOCUS was a pragmatic, multicentre, parallel group, double-blind, randomised, placebo-controlled trial done at 103 hospitals in the UK. Patients were eligible if they were aged 18 years or older, had a clinical stroke diagnosis, were enrolled and randomly assigned between 2 days and 15 days after onset, and had focal neurological deficits. Patients were randomly allocated fluoxetine 20 mg or matching placebo orally once daily for 6 months via a web-based system by use of a minimisation algorithm. The primary outcome was functional status, measured with the modified Rankin Scale (mRS), at 6 months. Patients, carers, health-care staff, and the trial team were masked to treatment allocation. Functional status was assessed at 6 months and 12 months after randomisation. Patients were analysed according to their treatment allocation. This trial is registered with the ISRCTN registry, number ISRCTN83290762. Findings Between Sept 10, 2012, and March 31, 2017, 3127 patients were recruited. 1564 patients were allocated fluoxetine and 1563 allocated placebo. mRS data at 6 months were available for 1553 (99·3%) patients in each treatment group. The distribution across mRS categories at 6 months was similar in the fluoxetine and placebo groups (common odds ratio adjusted for minimisation variables 0·951 [95% CI 0·839–1·079]; p=0·439). Patients allocated fluoxetine were less likely than those allocated placebo to develop new depression by 6 months (210 [13·43%] patients vs 269 [17·21%]; difference 3·78% [95% CI 1·26–6·30]; p=0·0033), but they had more bone fractures (45 [2·88%] vs 23 [1·47%]; difference 1·41% [95% CI 0·38–2·43]; p=0·0070). There were no significant differences in any other event at 6 or 12 months. Interpretation Fluoxetine 20 mg given daily for 6 months after acute stroke does not seem to improve functional outcomes. Although the treatment reduced the occurrence of depression, it increased the frequency of bone fractures. These results do not support the routine use of fluoxetine either for the prevention of post-stroke depression or to promote recovery of function. Funding UK Stroke Association and NIHR Health Technology Assessment Programme

Splenic rupture and subsequent splenectomy in a young healthy victim following Russell’s viper bite

Splenic rupture and/or splenectomy is/are not uncommon in clinical arena. Here we present this case of extensive haemorrhage-induced splenic rupture which resulted in splenectomy in a young healthy male (who did not have any previous medical conditions) following a Russell’s viper bite. He developed upper abdominal and shoulder pain on his left side along with hypotension and reduced level of haemoglobin on the third day following bite despite antivenom treatment. Following confirmation of splenic rupture and haemoperitoneum by ultrasound and computed tomography scans, an emergency splenectomy was performed using laparotomy. Although Russell’s viper bites are known to induce bleeding complications, splenic rupture due to haemorrhage in spleen has not been previously reported. Russell’s viper venom toxins such as metalloproteases, serine proteases and phospholipase A2 might have affected the vascular permeability resulting in excessive bleeding and increased pressure in the spleen leading to rupture. Further investigations are required to underpin the impact of snake venom toxins on the architecture and functions of spleen. However, the clinicians who treat snakebites should be aware of this type of rare complications so as to provide appropriate management for such victims

Pyrene-Modified quartz crystal microbalance for the detection of polynitroaromatic compounds

The synthesis of a dithiol-functionalized pyrene derivative is reported, together with studies of interactions between this receptor (and other related pyrenes) and nitroaromatic compounds (NACs), in both solution and in the solid state. Spectroscopic analysis in solution and X-ray crystallographic analysis of cocrystals of pyrene and NACs in the solid state indicate that supramolecular interactions lead to the formation of defined pi-pi stacked complexes. The dithiolfunctionalized pyrene derivative can be used to modify the surface of a gold quartz crystal microbalance (QCM) to create a unique π-electron rich surface, which is able to interact with electron poor aromatic compounds. For example, exposure of the modified QCM surface to the nitroaromatic compound 2,4-dinitrotoluene (DNT) in solution results in a reduction in the resonant frequency of the QCM as a result of supramolecular interactions between the electron-rich pyrenyl surface layer and the electron-poor DNT molecules. These results suggest the potential use of such modified QCM surfaces for the detection of explosive NACs

Millet-based intercropping systems facilitated by beneficial microbes for climate-resilient, sustainable farming in tropics

Climate change is arguably the biggest threat being faced by humankind, one that impacts billions of people through soil erosion, extreme droughts, uneven and unpredictable rains during the cropping season, rises in sea level, etc. Climate-induced droughts limit crop growth and productivity, eventually affecting millions of marginal farmers. Millets are predominantly grown in rainfed and arid regions, especially in the tropical zones of Asia and Africa. They are rich in macro and micronutrients that can complement other sources of nutrition such as cereals, vegetables, fruits, milk, meat and eggs. Millet-based intercropping systems have been practiced in India over centuries. Nevertheless, a sustainable intensification of millet-based intercropping has not yet been achieved. Recent research findings have shown that millet and legume intercropping facilitated by biofertilizers, such as arbuscular mycorrhizal fungi and plant-growth-promoting rhizobacteria, is a promising innovative tool. This chapter aims at exploring research and development perspectives for promoting millet-based intercropping systems for sustainable farming, particularly in the tropics

Spatial Arrangement and Biofertilizers Enhance the Performance of Legume - Millet Intercropping System in Rainfed Areas of Southern India

Intercropping is a well-established practice to enhance the yield in low-input agriculture, and beneficial microbes such as arbuscular mycorrhizal fungi (AMF) combined with plant growth promoting rhizobacteria are being used as an effective and sustainable measure to improve yields. In this study, we tested if biofertilizers can not only enhance the yield of crops in monoculture as has previously been demonstrated but can also enhance the yield of intercropping systems. We hypothesized that because AMF can form common mycorrhizal networks (CMN) that can transfer nutrients and water between different plant species, biofertilization can balance belowground competition between crop species and promote thus overall yields in intercropping systems. In our study, we used a pigeon pea (PP)—finger millet (FM) intercropping system that we grew for two consecutive growing seasons (2016/17 and 2017/18) at two contrasting sites in Bengaluru and Kolli Hills, India. We also tested if the spatial arrangement (i.e., different arrangement of component plants with similar plant density in intercropping system) of intercropped plants, using either a row-wise or a mosaic design, influences the effect of biofertilizers on yield and water relations of the PP-FM intercropping system. Our results demonstrate that intercropping can improve the straw and grain yield of PP and FM compared to the respective monocultures and that intercropping effects vary depending on the site characteristic such as climate and soil type. The spatial arrangement of component plants affected the total, straw, and grain biomass in intercropping treatments, but this effect also varied across sites. Most importantly, the results from the 2017/18 growing season clearly demonstrated a positive effect of biofertilizer on biomass yield, and this effect was irrespective of site, spatial arrangement, mixed or monoculture. Our study therefore shows that yield increase in intercropping systems can further be improved through the application of biofertilizers

Feasibility of reporting results of large randomised controlled trials to participants:experience from the Fluoxetine or Control under supervision (FOCUS) trial

Objectives Informing research participants of the results of studies in which they took part is viewed as an ethical imperative. However, there is little guidance in the literature about how to do this. The Fluoxetine Or Control Under Supervision trial randomised 3127 patients with a recent acute stroke to 6 months of fluoxetine or placebo and was published in the Lancet on 5 December 2018. The trial team decided to inform the participants of the results at exactly the same time as the Lancet publication, and also whether they had been allocated fluoxetine or placebo. In this report, we describe how we informed participants of the results.Design In the 6-month and 12-month follow-up questionnaires, we invited participants to provide an email address if they wished to be informed of the results of the trial. We re-opened our trial telephone helpline between 5 December 2018 and 31 March 2019.Setting UK stroke services.Participants 3127 participants were randomised. 2847 returned 6-month follow-up forms and 2703 returned 12-month follow-up forms; the remaining participants had died (380), withdrawn consent or did not respond.Results Of those returning follow-up questionnaires, a total of 1845 email addresses were provided and a further 50 people requested results to be sent by post. Results were sent to all email and postal addresses provided; 309 emails were returned unrecognised. Seventeen people replied, of whom three called the helpline and the rest responded by email.Conclusion It is feasible to disseminate results of large trials to research participants, though only around 60% of those randomised wanted to receive the results. The system we developed was efficient and required very little resource, and could be replicated by trialists in the future.Trial registration number ISRCTN83290762; Post-results