757 research outputs found
A re-examination of the Salicornias (Amaranthaceae) of Saudi Arabia and their polymorphs
During the period from 1964 to 1999 Saudi Arabian species of Salicornia were wrongly treated under the European species, S. europaea L. Recent explorations proved that there are two separate allopatric species of Salicornia in Saudi Arabia, one inhabiting the inland salt-marshes of the Najd (highlands) and the other inhabiting the Arabian Gulf Coast (lowlands). Morphological, ecological and exploratory studies confirm that they are two distinct species. The two species differ in features of bark, axillary spikes, basal vegetative segment(s) of spike, fertile segments, colour of senescent plants, and flowering, fruiting and germination phenology. As both the species have been described earlier from Iran, they are now new records for Saudi Arabia. The species are, S. persica ssp. iranica (Akhani) Kadereit & Piirainen and S. sinus-persica Akhani. S. sinus-persica, of which the status was thought doubtful has been confirmed. Both the species have been described and illustrated. Each species comprises a number of polymorphs. As leaves and flowers are rudimentary, confusing species circumscriptions, a proliferation of binomials has resulted in the taxonomy of Salicornia. To mitigate such confusion, the full range of variability of the Saudi Arabian species has been documented
Cytotoxic effect of acetogenins and sesquiterpenes obtained from the Red alga Laurencia majuscula
Purpose: To evaluate the cytotoxicity of n-hexane extract and its metabolites obtained from the red alga, Laurencia majuscula, against three cancer cell lines HCT-116 (colon cancer), PC-3 (prostate cancer) and HepG2 (liver cancer) cells; and to identify the phytochemical compound(s) involved.
Methods: Solvent extraction, thin layer chromatography, aluminum oxide column chromatography, and preparative thin layer chromatography (PTLC) were employed for isolating pure compounds from nhexane extract of Laurencia majuscula. Nuclear magnetic resonance (NMR) and mass spectrometry (MS) measurements were used for structural elucidation of the compounds. The cytotoxicity of the nonpolar extract and isolated compounds were evaluated against HCT, PC-3, and HepG2 cells using MTT assay, relative to the standard cytotoxic drug (cisplatin).
Results: Three sesquiterpenes (1, 2 and 8), and five acetogenins (3-7) were isolated from the n-hexane extract. The n-hexane extract showed higher potent cytotoxic effect than sesquiterpenes and the acetogenins (3-7).
Conclusion: These results indicate that the n-hexane extract of Laurencia majuscula exerts significant cytotoxicity against HCT-116, PC-3 and HepG2 cell lines, thus suggesting that the plant extract may be effective chemotherapeutic agents for the management of colon, postrate and liver cancer.
Keywords: Red Sea alga, Rhodomelaceae, Polyketides, Terpenes, Anticance
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A systematic review of patients', parents’ and healthcare professionals’ adrenaline auto-injector administration techniques
Introduction: In order to enable fast treatment response to anaphylactic reactions, adrenaline auto-injectors (AAI) have been developed and manufactured. It has been reported in several studies that administration technique is suboptimal. The primary purpose of this study was to review the nature and extent of the deficiencies in administration technique among patients, parents/caregivers and healthcare professionals.
Methods: Relevant publications were identified between 1998 and 2015 using two search methods: a keyword search in Embase, PubMed, British Nursing Index and Cumulative Index to Nursing and Allied Health Literature and a search of reference lists of relevant articles.
Results: Twenty-three studies met the inclusion criteria. Overall, 37% of patients, 32% of parents/caregivers and 21% of healthcare professionals demonstrated correct administration technique. For studies which employed a before-and-after training study design, correct technique was achieved in 77% of patients, 79% of caregivers and 65% of healthcare professionals. The most consistently observed error was the failure to hold the device in place for the recommended time. For patients, factors associated with good technique were being aged over 18 years, trained in AAI administration by an allergist, prescribed an AAI for more than 30 months, having a history of severe anaphylaxis and membership of a support group. For parents/caregivers in addition to those mentioned, being given a training device with which to practice, improved technique.
Discussion: There was wide variation in administration techniques reported. However, studies designed using before-and-after training show that even a brief demonstration and educational intervention can improve technique. Further studies are required to design and pilot acceptable and cost-effective educational materials
COMPARING CARDIAC REHABILITATION GUIDELINES
Objectives: Comparing Cardiac Rehabilitation Guidelines. Method: guidelines were searched alone and with combination with different nations in English language. To review information about the exercises modes, exercise intensity, testing, and monitoring of patients. Results: the United States, Canadian, United Kingdome, and European guidelines all have common components and have differences in the exercises modes and intensity. The United States, Canada, and European guideline suggest aerobic training should progressing from moderate to vigorous intensity through the program, these guidelines also suggest resistance training combined with the aerobic training to improve quality of life. The United Kingdome recommends lower intensity program and less ECG monitoring. Although the other guidelines recommend ECG exercises stress test for functional capacity assessment. Conclusion: guideline for the Mediterranean region should be assembled and after reviewing these guidelines, it is recommended to use ECG monitoring for functional assessment. Managing the risk factors is recommended in all the guidelines. Aerobic endurance training is recommended to advance from moderate to high intensity exercises combined with resistance training. These characteristics are safe for the patients and also showed improvements in patient’s health and quality of life. Article visualizations
Collagen Fibrils and Proteoglycans of Peripheral and Central Stroma of the Keratoconus Cornea - Ultrastructure and 3D Transmission Electron Tomography
Keratoconus (KC) is a progressive corneal disorder in which vision gradually deteriorates as a result of continuous conical protrusion and the consequent altered corneal curvature. While the majority of the literature focus on assessing the center of this diseased cornea, there is growing evidence of peripheral involvement in the disease process. Thus, we investigated the organization of collagen fibrils (CFs) and proteoglycans (PGs) in the periphery and center of KC corneal stroma. Three-dimensional transmission electron tomography on four KC corneas showed the degeneration of microfibrils within the CFs and disturbance in the attachment of the PGs. Within the KC corneas, the mean CF diameter of the central-anterior stroma was significantly (p ˂ 0.001) larger than the peripheral-anterior stroma. The interfibrillar distance of CF was significantly (p ˂ 0.001) smaller in the central stroma than in the peripheral stroma. PGs area and the density in the central KC stroma were larger than those in the peripheral stroma. Results of the current study revealed that in the pre- Descemet\u27s membrane stroma of the periphery, the degenerated CFs and PGs constitute biomechanically weak lamellae which are prone to disorganization and this suggests that the peripheral stroma plays an important role in the pathogenicity of the KC cornea
Mechanisms of Groucho-mediated repression revealed by genome-wide analysis of Groucho binding and activity
Antibody validation (A) Chromatin isolated and sheared exactly as for the ChIP-seq analysis was subjected to immunoprecipitation with the indicated amounts (in μl) of affinity purified antibody against the Gro GP domain used for the ChIP-seq analysis, and then probed in a western blot with both an anti-Gro monoclonal antibody (mAb) or the anti-GP antibody. The band indicated by the asterisk is a cross-reacting protein that is recognized in the western blot but that is not efficiently immunoprecipitated by the anti-GP antibody. Ab HC – antibody heavy chain. (B) Heat map showing overlap (Jacard similarity coefficient [96]) between the peaks called in the duplicate ChIP-seq experiments at each time point. (C) Representative genome browser tracts comparing duplicate ChIP-seq experiments. (D and E) Comparison of Gro binding patterns obtained by ChIP-seq using our anti-GP antibody with that obtained by ChIP-chip (0–12 hr embryos; modENCODE #597) and ChIP-seq (white pre-pupae; modENCODE #4981) using independently derived antibodies [40]. (PDF 588 kb
The application of electrical resistance measurements to water transport in lime–masonry systems
The paper describes an experimental determination of impedance spectroscopy derived resistance measurements to record water transport in lime–masonry systems. It strongly supports the use of Sharp Front theory and Boltzmann’s distribution law of statistical thermodynamics to corroborate the data obtained. A novel approach is presented for the application of impedance measurements to the water transport between freshly mixed mortars and clay brick substrates. Once placed, fresh mortar is dewatered by brick and during this time the volume fraction water content of the mortar is reduced. An equation is derived relating this change in water content to the bulk resistance of the mortar. Experimental measurements on hydraulic lime mortars placed in contact with brick prisms confirm the theoretical predictions. Further, the results indicate the time at which dewatering of a mortar bed of given depth is completed. The technique has then potential to be applied for in situ monitoring of dewatering as a means of giving insight into the associated changes in mechanical and chemical properties
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