84 research outputs found
Sustained Release Intraocular Drug Delivery Devices for Treatment of Uveitis
Corticosteroids have been the mainstay of uveitis therapy. When intraocular inflammation is unresponsive to steroids, or steroid related side effects become a concern, steroid-sparing medications may be administered which can be classified into immunosuppressive and immunomodulatory agents. Uveitis treatment can be delivered systemically, topically, periocularly or intraocularly. All of the above mentioned medications can entail significant systemic side effects, particularly if administered for prolonged durations, which may become treatment-limiting. Some medications, particularly hydrophobic compounds, may poorly cross the blood–retinal barrier. Topical medications, which have the least side effects, do not penetrate well into the posterior segment and are unsuitable for posterior uveitis which is often sight-threatening. Intraocular or periocular injections can deliver relatively high doses of drug to the eye with few or no systemic side effects. However, such injections are associated with significant complications and must often be repeated at regular intervals. Compliance with any form of regular medication can be a problem, particularly if its administration is associated with discomfort or if side effects are unpleasant. To overcome the above-mentioned limitations, an increasing number of sustained-release drug delivery devices using different mechanisms and containing a variety of agents have been developed to treat uveitis. This review discusses various current and future sustained-release ophthalmic drug delivery systems for treatment of uveitis
The value of serum osteoprotegerin levels in patients with angina like chest pain undergoing diagnostic coronary angiography
Background: Osteoprotegerin (OPG) is a member of the tumor necrosis factor superfamily.Recent evidence supports a relationship between serum OPG level and atherosclerosis. Theaim of this study was to evaluate the possible association of OPG with the presence of coronary artery disease (CAD), its severity and prognosis in patients with chest pain and suspected coronary stenosis.Methods: In this cross-sectional analytic study, 180 candidates of elective coronary artery angiography were recruited. Serum level of OPG was measured by ELISA method in all patientsand its relation with presence and severity of CAD based on a coronary atherosclerosis score (CAS) was assessed. Patients were followed for a mean period of about 24 ± 3.2 months andthe relationship between OPG levels and future cardiac events were evaluated.Results: The mean serum level of OPG was 1637 ± 226 pg/mL in those with CAD and 1295 ± 185 pg/mL (nonparametric p = 0.001) in those without it. There was a significant directcorrelation between the level of serum OPG and CAS (rho = 0.225, p = 0.002). The optimalcut-off point for predicting a significant coronary artery obstruction was a serum level of ≥ 1412 pg/mL with a sensitivity and specificity of 60% and 57.8%, respectively. Major adversecardiac events (MACE) including cardiovascular death, admission with acute coronary syndrome,or heart failure, was significantly higher in those with higher OPG levels (22 [34.3%]vs. 15 [16%], p = 0.012).Conclusions: There was a direct and significant correlation between the serum level of OPGand CAS. MACE occurred more commonly in those with higher baseline OPG levels
Immunocytochemical determination of the subcellular distribution of ascorbate in plants
Ascorbate is an important antioxidant in plants and fulfills many functions related to plant defense, redox signaling and modulation of gene expression. We have analyzed the subcellular distribution of reduced and oxidized ascorbate in leaf cells of Arabidopsis thaliana and Nicotiana tabacum by high-resolution immuno electron microscopy. The accuracy and specificity of the applied method is supported by several observations. First, preadsorption of the ascorbate antisera with ascorbic acid or dehydroascorbic acid resulted in the reduction of the labeling to background levels. Second, the overall labeling density was reduced between 50 and 61% in the ascorbate-deficient Arabidopsis mutants vtc1-2 and vtc2-1, which correlated well with biochemical measurements. The highest ascorbate-specific labeling was detected in nuclei and the cytosol whereas the lowest levels were found in vacuoles. Intermediate labeling was observed in chloroplasts, mitochondria and peroxisomes. This method was used to determine the subcellular ascorbate distribution in leaf cells of plants exposed to high light intensity, a stress factor that is well known to cause an increase in cellular ascorbate concentration. High light intensities resulted in a strong increase in overall labeling density. Interestingly, the strongest compartment-specific increase was found in vacuoles (fourfold) and in plastids (twofold). Ascorbate-specific labeling was restricted to the matrix of mitochondria and to the stroma of chloroplasts in control plants but was also detected in the lumen of thylakoids after high light exposure. In summary, this study reveals an improved insight into the subcellular distribution of ascorbate in plants and the method can now be applied to determine compartment-specific changes in ascorbate in response to various stress situations
Mathematical assessment of drug build-up in the posterior eye following transscleral delivery
Corticosteroids in ophthalmology : drug delivery innovations, pharmacology, clinical applications, and future perspectives
Sexually Transmitted Disease Surveillance Status in Iran from the Viewpoint of Involved Experts and Practitioners
Background: Due to the lack of sufficient and valid studies on STD surveillance system problems, evidence based decision-making is impossible. Therefore, using a qualitative approach to evaluate the system in terms of its weak points, strengths, threats and opportunities as well as finding appropriate solutions is necessary.
Methods: A Mixed Method approach was conducted. For a reciprocal evaluation of STD surveillance, participants were selected from two mutual groups of AIDS and STD experts and STD related practitioners through targeted and convenient sampling respectively. In-depth interview and filling checklist were applied for the first group while an open structured questionnaire was used for the second group. Qualitative data was classified and summarized through content analysis methods. Quantitative data was analyzed by descriptive statistics.
Results: A great number of patients did not seek care because of stigma, taboo, over the counter drugs, dissatisfaction with the services, and the cost of tests. STD surveillance in Iran is mostly affected by threats and weak points. Low participation of the private sector on one hand and mismanagement and budget constraints in the health system on the other hand were the most important weak points. Weakness in the current reporting system was the common weak point of the two groups.
Conclusion: In order to empower and promote STD surveillance and to follow WHO recommendations, designing a road map based on the opinions and experiences of experts and stakeholders and systematic review of studies is suggested.
Keywords: Sexually Transmitted disease (STD), Surveillance system, Ira
Abundance, diversity and prospecting of culturable phosphate solubilizing bacteria on soils under crop–pasture rotations in a no-tillage regime in Uruguay
7 páginas, 3 figuras, 3 tablas. -- The original publication is available at www.sciencedirect.comPhosphate solubilizing bacteria (PSB) abundance and diversity were examined during two consecutive years, 2007 and 2008, in a crop/pasture rotation experiment in Uruguay. The study site comprised five treatments with different soil use intensity under a no-tillage regime. In the first year of sampling, abundance of PSB was significantly higher in natural prairie (NP) and permanent pasture (PP) than in continuous cropping (CC); rotation treatments harbored populations that did not differ significantly from those in the others. The percentage of PSB relative to total heterotrophic bacteria ranged between 0.18%
and 13.13%. PSB diversity also showed statistical differences among treatments, with PP populations more diverse than those present in CC. In the second year sampled no differences were found in PSB abundance
or diversity. Two hundred and fifty PSB were isolated in 2007 and classified according to their phosphate solubilization activity in vitro. Twelve of these isolates showing the greatest solubilization activity were
selected for 16S rDNA sequencing. Ten isolates presumably belong to the genus Pseudomonas and two isolates showed high similarity with members of the genera Burkholderia and Acinetobacter.This work was partially financed by PDT-DICYT, PEDECIBA and Agencia Nacional de Investigación e Innovación (ANII) through
project FCE2007 331 (Uruguay). Collaboration between Montevideo and Salamanca staff was possible thanks to a scholarship
awarded to G. Azziz by the Agencia Española de Cooperación Internacional para el Desarrollo (AECID) (Spain). INIA provided the sites of study and logistics.Peer reviewe
Response of Glycine max to drought stress in relation to growth parameters and some key enzymes of carbon and nitrogen metabolism
Drought stress is one of the major constraints for production and yield of soybean (Glycine max). For this reason, identifying mechanisms associated with drought tolerance in soybean is very impotent for improving and increasing drought resistance by genetic engineering methods. In this study, the effect of drought on growth traits (plant height, fresh and dry weight of shoot and also fresh and dry weight of root) and enzyme activities of isocitrate dehydrogenase (ICDH), phosphoenolpyruvate carboxylase (PEPC), malate dehydrogenase (MDH), glutamine synthetase (GS) and nitrate reductase (NR) were assessed in drought sensitive and tolerant cultivars of soybean. The results showed that growth indicators are higher in drought tolerant cultivar under water availability (control) and water deficient when compared with those of drought sensitive cultivar. An increase in the activity of ICDH was observed in both the cultivars under drought stress as compared with their respective control plants but this activity was higher in tolerant cultivar. The activities of PEPC, MDH, GS and NR were significantly decreased in drought sensitive cultivar whereas the activities of these enzymes were higher in another cultivar. In general, the results of this study showed different behavior in the activities of assayed enzymes in two sets of soybean cultivars differing in drought tolerance and also decline of the activities of these enzymes in drought sensitive cultivar due to water deficit stress may be one of the possible reasons for decreased growth of the soybean plants under drought
- …