69 research outputs found
Effects of natural and inorganic management practices on the soil properties of sandy regosols during Yala season in Batticaloa district
Quality of soil is critical for plant growth, and hence, important to
agriculture. Management practices that are appropriate to improve soil characteristics
and climate can enhance soil quality and its fertility. Natural soil management is a
sustainable way of managing soil that benefits from recycling of natural resources. A
field experiment was conducted at the Crop Farm, Eastern University, Sri Lanka to
study the effects of natural and inorganic soil management practices during Yala 2010.
Two separate plots having 50 square meter extent were selected for this experiment.
One plot was managed naturally (natural soil) with mulching, green manuring and
application of soil amendments (Jiwamirta and Amutha karaisal) whereas other plot
(inorganic soil) was managed based on the recommendations of Department of
Agriculture, Sri Lanka including chemical fertilizers. Five soil samples from each plot
were analyzed for soil properties namely moisture content (MC), pH, electrical
conductivity (EC), total nitrogen, available potassium and phosphorus and organic
matter (OM). Statistical analysis was carried out using SAS. Natural soil consisted
significantly (P < 0.05) higher MC than the inorganic soil. The natural soil had a neutral
pH while the inorganic soil was acidic. OM content, EC, total nitrogen and available
potassium were significantly higher (P < 0.05) in natural soil. However, available
phosphorus was significantly lower in natural soil. Therefore, it could be concluded that
natural soil management practices improved soil properties better than inorganic
practices which could be environmental friendly and economically beneficial for the
farmers
Pesticide usage pattern for vegetable cultivation in Manmunai South & Eruvilpattu divisional secretariat Division of Batticaloa district, Sri Lanka
Batticaloa, is a coastal district in Sri Lanka. Vegetables except up-country vegetables sold in Batticaloa District are mainly grown in villages. Manmunai South and Eruvilpattu divisional secretariat (DS) division is a predominantly vegetable cultivating area in the Batticaloa district. Farmers in this region use variety of synthetic pesticides to protect vegetables. Recently public concern related to health risks associated with pesticide residues has been increased, substantially. Therefore, a study was conducted to find out pesticide usage practices of farmers on vegetable cultivation in Manmunai South and Eruvilpattu DS division. Stratified random sampling method was used to select respondents for the survey and the collected data were analyzed statistically. It was observed that, the usage of pesticides was higher in the study area. Vegetable farmers use more than 14 Insecticides to control pest infestation. Farmers in the study area apply pesticides more frequently. Highly pesticide sprayed crop is Brinjal. About 66% of the Chilli producing farmers and 84% of the Brinjal producing farmers apply pesticide more than 22 times per cropping season. Around 90% of the farmers apply more than the recommended dosage and frequency of the pesticides. It was noticed that more than 89% of the farmers harvest the produce before the recommended pre harvest interval. It was found out that farmers in the study area are not following recommended pesticide usage practices. Hence, it is essential to educate the farmers on recommended pesticide usage practices, reduced usage of synthetic pesticides and use of organic farming practices to reduce the ill effects of synthetic pesticides. DOI: http://dx.doi.org/10.3329/ijarit.v4i1.21092 Int. J. Agril. Res. Innov. & Tech. 4 (1): 53-56, June, 201
Pesticide storage, disposal and protective methods adapted by the vegetable farmers in the Manmunai south and Eruvilpattu divisional secretariat division of Batticaloa district, Sri Lanka
Batticaloa district is in the Eastern Part of Sri Lanka. Vegetables except up-country vegetables sold in Batticaloa district are
mainly grown in villages in the district. Manmunai South and Eruvilpattu divisional secretariat (DS) division is a
predominantly vegetable cultivating area in the Batticaloa district. Farmers in this region use variety of synthetic pesticides to
protect vegetables. Recently public concern related to health risks associated with pesticide residues in the vegetables has been
increased substantially. Therefore, a study was conducted to find out pesticide storage, disposal and protective methods
adapted by the farmers on vegetable cultivation in Manmunai South and Eruvilpattu DS division. Stratified random sampling
method was used to select respondents for the survey and collected data were analyzed statistically. It was observed that the
usage of pesticides is higher in the study area. There are no any proper storage methods practices by farmers and they are
highly negligent in proper disposal of empty containers. The farmers in the survey area never use any protective measures
before or during the spraying operations of pesticides. It was found that awareness related to pesticide usage, storage and
disposal methods by farmers were very low. Further, they are unaware of the ill effects of pesticides on human beings as well
as the environment itself. Awareness programmes are essential and recommended to change the attitudes of farmers to shift
them from traditional to environmental friendly pest control methods
Disease-specific, neurosphere-derived cells as models for brain disorders
There is a pressing need for patient-derived cell models of brain diseases that are relevant and robust enough to produce the large quantities of cells required for molecular and functional analyses. We describe here a new cell model based on patient-derived cells from the human olfactory mucosa, the organ of smell, which regenerates throughout life from neural stem cells. Olfactory mucosa biopsies were obtained from healthy controls and patients with either schizophrenia, a neurodevelopmental psychiatric disorder, or Parkinson's disease, a neurodegenerative disease. Biopsies were dissociated and grown as neurospheres in defined medium. Neurosphere-derived cell lines were grown in serum-containing medium as adherent monolayers and stored frozen. By comparing 42 patient and control cell lines we demonstrated significant disease-specific alterations in gene expression, protein expression and cell function, including dysregulated neurodevelopmental pathways in schizophrenia and dysregulated mitochondrial function, oxidative stress and xenobiotic metabolism in Parkinson's disease. The study has identified new candidate genes and cell pathways for future investigation. Fibroblasts from schizophrenia patients did not show these differences. Olfactory neurosphere-derived cells have many advantages over embryonic stem cells and induced pluripotent stem cells as models for brain diseases. They do not require genetic reprogramming and they can be obtained from adults with complex genetic diseases. They will be useful for understanding disease aetiology, for diagnostics and for drug discovery
Imaging of Flow Patterns with Fluorescent Molecular Rotors
Molecular rotors are a group of fluorescent molecules that form twisted intramolecular charge transfer states (TICT) upon photoexcitation. Some classes of molecular rotors, among them those that are built on the benzylidene malononitrile motif, return to the ground state either by nonradiative intramolecular rotation or by fluorescence emission. In low-viscosity solvents, intramolecular rotation dominates, and the fluorescence quantum yield is low. Higher solvent viscosities reduce the intramolecular rotation rate, thus increasing the quantum yield. We recently described a different mechanism whereby the fluorescence quantum yield of the molecular rotor also depends on the shear stress of the solvent. In this study, we examined a possible application for shear-sensitive molecular rotors for imaging flow patterns in fluidic chambers. Flow chambers with different geometries were constructed from polycarbonate or acrylic. Solutions of molecular rotors in ethylene glycol were injected into the chamber under controlled flow rates. LED-induced fluorescence (LIF) images of the flow chambers were taken with a digital camera, and the intensity difference between flow and no-flow images was visualized and compared to computed fluid dynamics (CFD) simulations. Intensity differences were detectable with average flow rates as low as 0.1 mm/s, and an exponential association between flow rate and intensity increase was found. Furthermore, a good qualitative match to computed fluid dynamics simulations was seen. On the other hand, prolonged exposure to light reduced the emission intensity. With its high sensitivity and high spatial and temporal resolution, imaging of flow patterns with molecular rotors may become a useful tool in microfluidics, flow measurement, and control
Factors associated with worse lung function in cystic fibrosis patients with persistent staphylococcus aureus
Background Staphylococcus aureus is an important pathogen in cystic fibrosis (CF). However, it is not clear which factors are associated with worse lung function in patients with persistent S. aureus airway cultures. Our main hypothesis was that patients with high S. aureus density in their respiratory specimens would more likely experience worsening of their lung disease than patients with low bacterial loads. Methods Therefore, we conducted an observational prospective longitudinal multi-center study and assessed the association between lung function and S. aureus bacterial density in respiratory samples, co-infection with other CF-pathogens, nasal S. aureus carriage, clinical status, antibiotic therapy, IL-6- and IgG-levels against S. aureus virulence factors. Results 195 patients from 17 centers were followed; each patient had an average of 7 visits. Data were analyzed using descriptive statistics and generalized linear mixed models. Our main hypothesis was only supported for patients providing throat specimens indicating that patients with higher density experienced a steeper lung function decline (p<0.001). Patients with exacerbations (n = 60), S. aureus small-colony variants (SCVs, n = 84) and co-infection with Stenotrophomonas maltophilia (n = 44) had worse lung function (p = 0.0068; p = 0.0011; p = 0.0103). Patients with SCVs were older (p = 0.0066) and more often treated with trimethoprim/sulfamethoxazole (p = 0.0078). IL-6 levels positively correlated with decreased lung function (p<0.001), S. aureus density in sputa (p = 0.0016), SCVs (p = 0.0209), exacerbations (p = 0.0041) and co-infections with S. maltophilia (p = 0.0195) or A. fumigatus (p = 0.0496). Conclusions In CF-patients with chronic S. aureus cultures, independent risk factors for worse lung function are high bacterial density in throat cultures, exacerbations, elevated IL-6 levels, presence of S. aureus SCVs and co-infection with S. maltophilia
Apparent Shear Sensitivity of Molecular Rotors in Various Solvents
Fluorescent environment-sensitive dyes often change their spectral properties concomitantly with multiple solvent properties, such as polarity, protonation, hydrogen bond formation, or viscosity. Careful consideration of the response is needed when a fluorescent dye is used to report a single property. Recently, we observed an increase of emission intensity of viscosity-sensitive molecular rotors in fluids subject to flow and speculated that either polar-polar interaction or hydrogen bond formation play a role in the apparent flow sensitivity. In this study, we show experimental evidence that photoisomerization to an isomer with a lower quantum yield, first proposed by Rumble et al. (J Phys Chem A 116(44):10786-10792, 2012), plays a key role in the observed phenomenon. We subjected four molecular rotors with different electron acceptor motifs to fluid flow in solvents of different polarity and ability to form hydrogen bonds. We also measured the isomerization dynamics in a custom fluorophotometer with extremely low light exposure. Our results indicate that the photoisomerization rate depends both on the solvent and on the electron acceptor group, as does the recovery of the original isomer in the dark. In most solvents, recovery of the dark isomer is much more rapid than originally reported, and a state of quasi-equilibrium between both isomers is possible. Moreover, the sensitivity (i.e., relative intensity increase at the same flow rate) is also solvent-dependent. The intensity increase can be detected at very low velocities (as low as 0.06 mm/s). Characteristic for fluorescent dyes is the high spatial resolution, and no flow measurement device with comparable sensitivity and spatial resolution exists, although the nature of the solvent needs to be taken into account for quantitative flow measurement
Triple Therapy for Cystic Fibrosis Phe508delâGating and âResidual Function Genotypes
BACKGROUND
Elexacaftorâtezacaftorâivacaftor is a small-molecule cystic fibrosis transmembrane conductance regulator (CFTR) modulator regimen shown to be efficacious in patients with at least one Phe508del allele, which indicates that this combination can modulate a single Phe508del allele. In patients whose other CFTR allele contains a gating or residual function mutation that is already effectively treated with previous CFTR modulators (ivacaftor or tezacaftorâivacaftor), the potential for additional benefit from restoring Phe508del CFTR protein function is unclear.
METHODS
We conducted a phase 3, double-blind, randomized, active-controlled trial involving patients 12 years of age or older with cystic fibrosis and Phe508delâgating or Phe508delâresidual function genotypes. After a 4-week run-in period with ivacaftor or tezacaftorâivacaftor, patients were randomly assigned to receive elexacaftorâtezacaftorâivacaftor or active control for 8 weeks. The primary end point was the absolute change in the percentage of predicted forced expiratory volume in 1 second (FEV1) from baseline through week 8 in the elexacaftorâtezacaftorâivacaftor group.
RESULTS
After the run-in period, 132 patients received elexacaftorâtezacaftorâivacaftor and 126 received active control. Elexacaftorâtezacaftorâivacaftor resulted in a percentage of predicted FEV1 that was higher by 3.7 percentage points (95% confidence interval [CI], 2.8 to 4.6) relative to baseline and higher by 3.5 percentage points (95% CI, 2.2 to 4.7) relative to active control and a sweat chloride concentration that was lower by 22.3 mmol per liter (95% CI, 20.2 to 24.5) relative to baseline and lower by 23.1 mmol per liter (95% CI, 20.1 to 26.1) relative to active control (P<0.001 for all comparisons). The change from baseline in the Cystic Fibrosis QuestionnaireâRevised respiratory domain score (range, 0 to 100, with higher scores indicating better quality of life) with elexacaftorâtezacaftorâivacaftor was 10.3 points (95% CI, 8.0 to 12.7) and with active control was 1.6 points (95% CI, â0.8 to 4.1). The incidence of adverse events was similar in the two groups; adverse events led to treatment discontinuation in one patient (elevated aminotransferase level) in the elexacaftorâtezacaftorâivacaftor group and in two patients (anxiety or depression and pulmonary exacerbation) in the active control group.
CONCLUSIONS
Elexacaftorâtezacaftorâivacaftor was efficacious and safe in patients with Phe508delâgating or Phe508delâresidual function genotypes and conferred additional benefit relative to previous CFTR modulators. (Funded by Vertex Pharmaceuticals; VX18-445-104 ClinicalTrials.gov number, NCT04058353.
NRF2 Activation Restores Disease Related Metabolic Deficiencies in Olfactory Neurosphere-Derived Cells from Patients with Sporadic Parkinson's Disease
Extent: 14p.Background: Without appropriate cellular models the etiology of idiopathic Parkinsonâs disease remains unknown. We recently reported a novel patient-derived cellular model generated from biopsies of the olfactory mucosa (termed olfactory neurosphere-derived (hONS) cells) which express functional and genetic differences in a disease-specific manner. Transcriptomic analysis of Patient and Control hONS cells identified the NRF2 transcription factor signalling pathway as the most differentially expressed in Parkinsonâs disease. Results: We tested the robustness of our initial findings by including additional cell lines and confirmed that hONS cells from Patients had 20% reductions in reduced glutathione levels and MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)- 2-(4-sulfophenyl)-2H-tetrazolium, inner salt] metabolism compared to cultures from healthy Control donors. We also confirmed that Patient hONS cells are in a state of oxidative stress due to higher production of H2O2 than Control cultures. siRNA-mediated ablation of NRF2 in Control donor cells decreased both total glutathione content and MTS metabolism to levels detected in cells from Parkinsonâs Disease patients. Conversely, and more importantly, we showed that activation of the NRF2 pathway in Parkinsonâs disease hONS cultures restored glutathione levels and MTS metabolism to Control levels. Paradoxically, transcriptomic analysis after NRF2 pathway activation revealed an increased number of differentially expressed mRNAs within the NRF2 pathway in L-SUL treated Patient-derived hONS cells compared to L-SUL treated Controls, even though their metabolism was restored to normal. We also identified differential expression of the PI3K/AKT signalling pathway, but only post-treatment. Conclusions: Our results confirmed NRF2 as a potential therapeutic target for Parkinsonâs disease and provided the first demonstration that NRF2 function was inducible in Patient-derived cells from donors with uniquely varied genetic backgrounds. However, our results also demonstrated that the response of PD patient-derived cells was not co-ordinated in the same way as in Control cells. This may be an important factor when developing new therapeutics.Anthony L. Cook, Alejandra M. Vitale, Sugandha Ravishankar, Nicholas Matigian, Greg T. Sutherland, Jiangou Shan, Ratneswary Sutharsan, Chris Perry, Peter A. Silburn, George D. Mellick, Murray L. Whitelaw, Christine A. Wells, Alan Mackay-Sim and Stephen A. Woo
Safety and efficacy of vanzacaftorâtezacaftorâdeutivacaftor in adults with cystic fibrosis: randomised, double-blind, controlled, phase 2 trials
Background
Elexacaftorâtezacaftorâivacaftor has been shown to be safe and efficacious in people with cystic fibrosis and at least one F508del allele. Our aim was to identify a novel cystic fibrosis transmembrane conductance regulator (CFTR) modulator combination capable of further increasing CFTR-mediated chloride transport, with the potential for once-daily dosing.
Methods
We conducted two phase 2 clinical trials to assess the safety and efficacy of a once-daily combination of vanzacaftorâtezacaftorâdeutivacaftor in participants with cystic fibrosis who were aged 18 years or older. A phase 2 randomised, double-blind, active-controlled study (VX18-561-101; April 17, 2019, to Aug 20, 2020) was carried out to compare deutivacaftor monotherapy with ivacaftor monotherapy in participants with CFTR gating mutations, following a 4-week ivacaftor monotherapy run-in period. Participants were randomly assigned to receive either ivacaftor 150 mg every 12 h, deutivacaftor 25 mg once daily, deutivacaftor 50 mg once daily, deutivacaftor 150 mg once daily, or deutivacaftor 250 mg once daily in a 1:1:2:2:2 ratio. The primary endpoint was absolute change in ppFEV1 from baseline at week 12. A phase 2 randomised, double-blind, controlled, proof-of-concept study of vanzacaftorâtezacaftorâdeutivacaftor (VX18-121-101; April 30, 2019, to Dec 10, 2019) was conducted in participants with cystic fibrosis and heterozygous for F508del and a minimal function mutation (F/MF genotypes) or homozygous for F508del (F/F genotype). Participants with F/MF genotypes were randomly assigned 1:2:2:1 to receive either 5 mg, 10 mg, or 20 mg of vanzacaftor in combination with tezacaftorâdeutivacaftor or a triple placebo for 4 weeks, and participants with the F/F genotype were randomly assigned 2:1 to receive either vanzacaftor (20 mg)âtezacaftorâdeutivacaftor or tezacaftorâivacaftor active control for 4 weeks, following a 4-week tezacaftorâivacaftor run-in period. Primary endpoints for part 1 and part 2 were safety and tolerability and absolute change in ppFEV1 from baseline to day 29. Secondary efficacy endpoints were absolute change from baseline at day 29 in sweat chloride concentrations and Cystic Fibrosis Questionnaire-Revised (CFQ-R) respiratory domain score. These clinical trials are registered with ClinicalTrials.gov, NCT03911713 and NCT03912233, and are complete.
Findings
In study VX18-561-101, participants treated with deutivacaftor 150 mg once daily (n=23) or deutivacaftor 250 mg once daily (n=24) had mean absolute changes in ppFEV1 of 3·1 percentage points (95% CI â0·8 to 7·0) and 2·7 percentage points (â1·0 to 6·5) from baseline at week 12, respectively, versus â0·8 percentage points (â6·2 to 4·7) with ivacaftor 150 mg every 12 h (n=11); the deutivacaftor safety profile was consistent with the established safety profile of ivacaftor 150 mg every 12 h. In study VX18-121-101, participants with F/MF genotypes treated with vanzacaftor (5 mg)âtezacaftorâdeutivacaftor (n=9), vanzacaftor (10 mg)âtezacaftorâdeutivacaftor (n=19), vanzacaftor (20 mg)âtezacaftorâdeutivacaftor (n=20), and placebo (n=10) had mean changes relative to baseline at day 29 in ppFEV1 of 4·6 percentage points (â1·3 to 10·6), 14·2 percentage points (10·0 to 18·4), 9·8 percentage points (5·7 to 13·8), and 1·9 percentage points (â4·1 to 8·0), respectively, in sweat chloride concentration of â42·8 mmol/L (â51·7 to â34·0), â45·8 mmol/L (95% CI â51·9 to â39·7), â49·5 mmol/L (â55·9 to â43·1), and 2·3 mmol/L (â7·0 to 11·6), respectively, and in CFQ-R respiratory domain score of 17·6 points (3·5 to 31·6), 21·2 points (11·9 to 30·6), 29·8 points (21·0 to 38·7), and 3·3 points (â10·1 to 16·6), respectively. Participants with the F/F genotype treated with vanzacaftor (20 mg)âtezacaftorâdeutivacaftor (n=18) and tezacaftorâivacaftor (n=10) had mean changes relative to baseline (taking tezacaftorâivacaftor) at day 29 in ppFEV1 of 15·9 percentage points (11·3 to 20·6) and â0·1 percentage points (â6·4 to 6·1), respectively, in sweat chloride concentration of â45·5 mmol/L (â49·7 to â41·3) and â2·6 mmol/L (â8·2 to 3·1), respectively, and in CFQ-R respiratory domain score of 19·4 points (95% CI 10·5 to 28·3) and â5·0 points (â16·9 to 7·0), respectively. The most common adverse events overall were cough, increased sputum, and headache. One participant in the vanzacaftorâtezacaftorâdeutivacaftor group had a serious adverse event of infective pulmonary exacerbation and another participant had a serious rash event that led to treatment discontinuation. For most participants, adverse events were mild or moderate in severity.
Interpretation
Once-daily dosing with vanzacaftorâtezacaftorâdeutivacaftor was safe and well tolerated and improved lung function, respiratory symptoms, and CFTR function. These results support the continued investigation of vanzacaftorâtezacaftorâdeutivacaftor in phase 3 clinical trials compared with elexacaftorâtezacaftorâivacaftor.
Funding
Vertex Pharmaceuticals
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