Local Knowledge and Conservation of Seagrasses in the Tamil Nadu State of India

Local knowledge systems are not considered in the conservation of fragile seagrass marine ecosystems. In fact, little is known about the utility of seagrasses in local coastal communities. This is intriguing given that some local communities rely on seagrasses to sustain their livelihoods and have relocated their villages to areas with a rich diversity and abundance of seagrasses. The purpose of this study is to assist in conservation efforts regarding seagrasses through identifying Traditional Ecological Knowledge (TEK) from local knowledge systems of seagrasses from 40 coastal communities along the eastern coast of India. We explore the assemblage of scientific and local traditional knowledge concerning the 1. classification of seagrasses (comparing scientific and traditional classification systems), 2. utility of seagrasses, 3. Traditional Ecological Knowledge (TEK) of seagrasses, and 4. current conservation efforts for seagrass ecosystems. Our results indicate that local knowledge systems consist of a complex classification of seagrass diversity that considers the role of seagrasses in the marine ecosystem. This fine-scaled ethno-classification gives rise to five times the number of taxa (10 species = 50 local ethnotaxa), each with a unique role in the ecosystem and utility within coastal communities, including the use of seagrasses for medicine (e.g., treatment of heart conditions, seasickness, etc.), food (nutritious seeds), fertilizer (nutrient rich biomass) and livestock feed (goats and sheep). Local communities are concerned about the loss of seagrass diversity and have considerable local knowledge that is valuable for conservation and restoration plans. This study serves as a case study example of the depth and breadth of local knowledge systems for a particular ecosystem that is in peril.     

Pre-clinical evaluation of an sLe x-glycosylated complement inhibitory protein in a non-human primate model of reperfused stroke

BACKGROUND: Soluble complement receptor-1 (sCR1), a potent complement inhibitor, confers neuroprotection in a murine stroke model. Additional neuroprotective benefit is achieved by sLe x-glycosylation of sCR1. In an effort to translate sCR1-sLe x to clinical trials, we evaluated this agent in a primate stroke model. METHODS: Adult male baboons randomly received either sCR1-sLe x or vehicle. Stroke volume was assessed on day 3, and neurological examinations were conducted daily. Complement activity (CH50) was measured at 30 minute, 2, 6, 12 hour, 3, and 10 days post-ischemia. RESULTS: The experiment was terminated prematurely following an interim analysis. In a preliminary cohort (n = 3 per arm), infarct volume was greater in the treated animals. No difference in neurological score was found between groups. CH50 levels were significantly reduced in the sCR1sLe x-treated groups. A hypotensive response was also observed in animals treated with sCR1-sLe x. Conclusions Further work is necessary to explain the hypotensive response observed in primates prior to further clinical development of sCR1-sLe x.     

Chlorophyll thermofluorescence and thermoluminescence as complementary tools for the study of temperature stress in plants

The photosynthetic apparatus, especially the electron transport chain imbedded in the thylakoid membrane, is one of the main targets of cold and heat stress in plants. Prompt and delayed fluorescence emission originating from photosystem II have been used, most often separately, to monitor the changes induced in the photosynthetic membranes during progressive warming or cooling of a leaf sample. Thermofluorescence of F ₀ and F _M informs on the effects of heat on the chlorophyll antennae and the photochemical centers, thermoluminescence on the stabilization and movements of charges and Delayed Light Emission on the permeability of the thylakoid membranes to protons and ions. Considered together and operated simultaneously, these techniques constitute a powerful tool to characterize the effect of thermal stress on intact photosynthetic systems and to understand the mechanisms of constitutive or induced tolerance to temperature stresses.     

A predictive model for respiratory syncytial virus (RSV) hospitalisation of premature infants born at 33–35 weeks of gestational age,based on data from the Spanish FLIP study

Background

The aim of this study, conducted in Europe, was to develop a validated risk factor based model to predict RSV-related hospitalisation in premature infants born 33–35 weeks'' gestational age (GA).

Methods

The predictive model was developed using risk factors captured in the Spanish FLIP dataset, a case-control study of 183 premature infants born between 33–35 weeks'' GA who were hospitalised with RSV, and 371 age-matched controls. The model was validated internally by 100-fold bootstrapping. Discriminant function analysis was used to analyse combinations of risk factors to predict RSV hospitalisation. Successive models were chosen that had the highest probability for discriminating between hospitalised and non-hospitalised infants. Receiver operating characteristic (ROC) curves were plotted.

Results

An initial 15 variable model was produced with a discriminant function of 72% and an area under the ROC curve of 0.795. A step-wise reduction exercise, alongside recalculations of some variables, produced a final model consisting of 7 variables: birth ± 10 weeks of start of season, birth weight, breast feeding for ≤ 2 months, siblings ≥ 2 years, family members with atopy, family members with wheeze, and gender. The discrimination of this model was 71% and the area under the ROC curve was 0.791. At the 0.75 sensitivity intercept, the false positive fraction was 0.33. The 100-fold bootstrapping resulted in a mean discriminant function of 72% (standard deviation: 2.18) and a median area under the ROC curve of 0.785 (range: 0.768–0.790), indicating a good internal validation. The calculated NNT for intervention to treat all at risk patients with a 75% level of protection was 11.7 (95% confidence interval: 9.5–13.6).

Conclusion

A robust model based on seven risk factors was developed, which is able to predict which premature infants born between 33–35 weeks'' GA are at highest risk of hospitalisation from RSV. The model could be used to optimise prophylaxis with palivizumab across Europe.     

A mouse model of intracerebral hemorrhage using autologous blood infusion

The development of controllable and reproducible animal models of intracerebral hemorrhage (ICH) is essential for the systematic study of the pathophysiology and treatment of hemorrhagic stroke. In recent years, we have used a modified version of a murine ICH model to inject blood into mouse basal ganglia. According to our protocol, autologous blood is stereotactically infused in two stages into the right striatum to mimic the natural events of hemorrhagic stroke. Following ICH induction, animals demonstrate reproducible hematomas, brain edema formation and marked neurological deficits. Our technique has proven to be a reliable and reproducible means of creating ICH in mice in a number of acute and chronic studies. We believe that our model will serve as an ideal paradigm for investigating the complex pathophysiology of hemorrhagic stroke. The protocol for establishing this model takes about 2 h.     

Diacylglycerols interact with the L2 lipidation site in TRPC3 to induce a sensitized channel state

Coordination of lipids within transient receptor potential canonical channels (TRPCs) is essential for their Ca²⁺ signaling function. Single particle cryo‐EM studies identified two lipid interaction sites, designated L1 and L2, which are proposed to accommodate diacylglycerols (DAGs). To explore the role of L1 and L2 in TRPC3 function, we combined structure‐guided mutagenesis and electrophysiological recording with molecular dynamics (MD) simulations. MD simulations indicate rapid DAG accumulation within both L1 and L2 upon its availability within the plasma membrane. Electrophysiological experiments using a photoswitchable DAG‐probe reveal potentiation of TRPC3 currents during repetitive activation by DAG. Importantly, initial DAG exposure generates a subsequently sensitized channel state that is associated with significantly faster activation kinetics. TRPC3 sensitization is specifically promoted by mutations within L2, with G652A exhibiting sensitization at very low levels of active DAG. We demonstrate the ability of TRPC3 to adopt a closed state conformation that features partial lipidation of L2 sites by DAG and enables fast activation of the channel by the phospholipase C‐DAG pathway.     

Identification of novel Y chromosome encoded transcripts by testis transcriptome analysis of mice with deletions of the Y chromosome long arm

Background  

The male-specific region of the mouse Y chromosome long arm (MSYq) is comprised largely of repeated DNA, including multiple copies of the spermatid-expressed Ssty gene family. Large deletions of MSYq are associated with sperm head defects for which Ssty deficiency has been presumed to be responsible.     

Role of the oxidized secondary acceptor Q B of Photosystem II in the delayed ‘afterglow’ chlorophyll luminescence

Leaf discs of dark-adapted tobacco plants were excited by 2 flashes and kept in darkness at 20 °C for various time periods, then thermoluminescence emission was recorded without freezing the sample. The B band at 30 °C decreased with a half-time t_1/2~1 min and the AG band at 45 °C with a t_1/2~5 min. This corresponds to the decay kinetics of S_2/3 in PS II centres in the state S_2/3 Q_B^- (B band) or S_2/3 Q_B. Assuming that the 45 °C band is an ‘afterglow’ emission originating from those centres with an oxidized Q_B on which an electron is back-transferred from stroma reductants through a pathway induced by warming, the theoretical ratio of the B and AG band was compared to that measured experimentally. After 2 or 3 flashes producing mainly S₃, the intensity of AG band encompassed several fold that of the B band, because recombining S₃ recreated S₂ Q_B AG-emitting centres. In order to confirm that the AG band is governed by the heat-induced activation of a dark Q_B-reducing pathway rather than by PS II charge recombination, the AG emission was characterized in triazine-resistant Chenopodium album weed biotypes. In these mutants where the Q_B pocket is altered, the B band is strongly downshifted to 18 °C, compared to 32 °C in the wild type, whereas the AG band is only downshifted by 3 or 4 °C, demonstrating that S_2/3 Q_B^- is not the limiting step of the AG emission.