25 research outputs found
The mechanism of formation of 8,8-dimethyl[4.2.1.0 3,7]nonan-6-yl acetate (fortesyl acetate) during acetolysis of nopyl toluene-psulfonate
Attempts to prepare 2-(2-hydroxyethyl)-6,6-dimethylbicyclo[3.1.1]hept-2-ene (nopol; 1) labelled with deuterium at
C-10 by a process of oxidation of the primary alcohol group of nopol to the aldehyde, followed by H/D exchange
and reduction back to alcohol, were unsuccessful because various oxidation procedures, including reaction with
N-chlorosuccinimide at 278 8C, gave instead a carboxylic acid having an oxygen at C-3. Nopol, labelled at C-11
with deuterium, was obtained through a Prins reaction of b-pinene with deuteriated paraformaldehyde. This
labelled nopol was converted into its toluene-p-sulfonate ester, and was solvolysed in acetic acid containing acetate
ion to give 8,8-dimethyltricyclo[4.2.1.03,7]nonan-6-yl acetate, which is an earlier reported novel fused ring system
(fortesyl acetate; 2 acetate). The position of the label in the product showed that the mechanism of this deep-seated
carbon skeletal rearrangement proceeds through the intermediate formation of a cyclobutane ring, followed by
shift of a methylene bridge to expand the original cyclobutane ring and then subsequent expansion of the new
cyclobutane ring. Calculations of heats of formation of possible ions involved in these shifts confirm the proposed
mechanism as the most likely pathway.Junta Nacional de Investigação Científica e Tecnológica.
Kuwait.
Eschenmoser Trust UK
Quantitative Determination of Cellular-and Neurite Motility Speed in Dense Cell Cultures
Mobility quantification of single cells and cellular processes in dense cultures is a challenge, because single cell tracking is impossible. We developed a software for cell structure segmentation and implemented 2 algorithms to measure motility speed. Complex algorithms were tested to separate cells and cellular components, an important prerequisite for the acquisition of meaningful motility data. Plasma membrane segmentation was performed to measure membrane contraction dynamics and organelle trafficking. The discriminative performance and sensitivity of the algorithms were tested on different cell types and calibrated on computer-simulated cells to obtain absolute values for cellular velocity. Both motility algorithms had advantages in different experimental setups, depending on the complexity of the cellular movement. The correlation algorithm (COPRAMove) performed best under most tested conditions and appeared less sensitive to variable cell densities, brightness and focus changes than the differentiation algorithm (DiffMove). In summary, our software can be used successfully to analyze and quantify cellular and subcellular movements in dense cell cultures
Developing Affimers for the detection of biomarkers in cancer
Biomarkers are molecules present in the patients’ samples. They are used to detect the presence of a disease or an infection. An array of laboratory tools is used to monitor changes in the biomarker levels for diagnostic and prognostic purposes. Affimers are relatively new tools, which can be used in similar ways to commonly used antibodies with many advantages over the later. The work described in this PhD thesis has focused on a number of methodologies for the generation of Affimers against purified proteins and cell-surface molecules, with the intention of using these to detect biomarkers in cancer. To ensure the development of functional Affimer reagents against different membrane target molecules, EGFR, HER2, and HER3 were used as models to optimise the process of Affimers isolation and selection using phage display technology. In vitro production of Affimers using bacterial cells was assessed and optimised. Following optimisation, a range of Affimers that bound to EGFR, HER2, and HER3 were generated and partially characterised by different molecular applications, including immunofluorescence, immunohistochemistry, and pull-down assay. Upon characterisation, the developed reagents were not only able to identify their targets on cells and to precipitate them down from cell lysates, but also exhibited a complete inhibition of the downstream signalling activation of both EGFR and HER3. In addition, this thesis provides clear evidence of the potential of Affimers in biomarker discovery studies. After multiple rounds on non-tumourigenic (HB2) and cancerous (MDA-MB-453) breast-cell lines, eight novel anti-breast-cancer Affimers were successfully isolated and characterised. Following pull-down assay and mass spectrometry analysis, the target proteins to which these Affimers were found to bind was identified as CK18 and 19. Upon identification, the specificity of Affimers was further validated on a panel of breast cells, tissues, and on multiple breast-tissue microarrays (TMAs). There is a need to develop the knowledge to utilise this new Affimers-based technology to encourage adoption of this useful tool. With the aid of such technology, several novel detection reagents were generated, partially validated and proved to be promising tools for biomarker detection in different conventional assays
Neurological Complications in Sickle Cell Disease
Abstract Sickle cell disease is a common inherited blood disorder that affects red blood cells. It is a hemoglobinopathy characterized by hemoglobin polymerization, erythrocyte stiffening, and subsequent vaso-occlusions. These changes can lead to microcirculation obstructions, tissue ischemia, infarction and acute stroke. In addition, chronic cerebral ischemia and cerebral vascular anomalies are considered among the most disabling problems in sickle cell disease. Neurological complications of sickle cell disease include, Ischaemic Stroke, hemorrhagic stroke, transient ischemic attack, silent cerebral infarction, headache, Moyamoya disease, neuropathic pain, and neurocognitive impairment. Early diagnosis and proper management of sickle cell disease neurological complications require specialised hematological and neurological experties. The newly used medications under ongoing research foster the hope to overcome this devastating disease and its complications
Children with Type 1 Diabetes
© 2015, Bahrain Medical Bulletin. All Rights Reserved.Background: The prevalence of diabetes in the Middle East is amongst the highest worldwide; Bahrain ranks amongst the top 10 countries. In particular, increasing number of children are being diagnosed with type 1 diabetes mellitus (T1DM) posing a significant public health concern. Objective: To evaluate the magnitude of type 1 diabetes in Bahrain. Design: A Case-Control Retrospective Study. Setting: Pediatric Diabetes and Endocrine Clinic and Local Health Centers (LHC). Method: Fifty-nine cases and 53 controls were included in the study. Data from the Diabetes Registry were recorded for subjects meeting the inclusion criteria and questionnaire was administered to healthy controls. Chi Square or Student’s t-test was used as appropriate. Logistic regression analysis was used to evaluate independent predictors of T1DM. Result: Fifty-nine children aged 6-12 years diagnosed with T1DM in the years 2009 and 2010 were compared to 53 healthy controls. Children with T1DM were more likely to have suffered from a pre-diabetes illness such as tonsillitis 32 (54.2%) compared to controls 3 (5.7%), and have undergone a surgery prior to diagnosis 14 (23.7%), and to have mothers with T2DM or family history of GDM. No significant difference in infant-feeding practices was observed between children with type 1 diabetes and the healthy controls. Conclusion: Children with T1DM were more likely to have suffered from other infectious illnesses before the diagnosis was established. Whilst unable to fully investigate any potential genetic differences between cases and controls, this study provides support for the theoretical role of infections as a trigger for T1DM
Children with Type 1 Diabetes
© 2015, Bahrain Medical Bulletin. All Rights Reserved.Background: The prevalence of diabetes in the Middle East is amongst the highest worldwide; Bahrain ranks amongst the top 10 countries. In particular, increasing number of children are being diagnosed with type 1 diabetes mellitus (T1DM) posing a significant public health concern. Objective: To evaluate the magnitude of type 1 diabetes in Bahrain. Design: A Case-Control Retrospective Study. Setting: Pediatric Diabetes and Endocrine Clinic and Local Health Centers (LHC). Method: Fifty-nine cases and 53 controls were included in the study. Data from the Diabetes Registry were recorded for subjects meeting the inclusion criteria and questionnaire was administered to healthy controls. Chi Square or Student’s t-test was used as appropriate. Logistic regression analysis was used to evaluate independent predictors of T1DM. Result: Fifty-nine children aged 6-12 years diagnosed with T1DM in the years 2009 and 2010 were compared to 53 healthy controls. Children with T1DM were more likely to have suffered from a pre-diabetes illness such as tonsillitis 32 (54.2%) compared to controls 3 (5.7%), and have undergone a surgery prior to diagnosis 14 (23.7%), and to have mothers with T2DM or family history of GDM. No significant difference in infant-feeding practices was observed between children with type 1 diabetes and the healthy controls. Conclusion: Children with T1DM were more likely to have suffered from other infectious illnesses before the diagnosis was established. Whilst unable to fully investigate any potential genetic differences between cases and controls, this study provides support for the theoretical role of infections as a trigger for T1DM
Feasibility of long-term irrigation as a treatment method for municipal wastewater using natural soil in Kuwait
Passing treated wastewater through soil is a natural and economic means to improve the quality of wastewater. The United Agricultural Production Company (UAPCO) farm located in the Sulaibiya area of Kuwait has been irrigated with tertiary treated wastewater since 1976. A field investigation at the farm has been conducted by the Kuwait Institute for Scientific Research (KISR) to assess the applicability of the natural soil treatment method, in the long term, to improve the quality of the treated wastewater under the conditions prevailing in Kuwait. The collected data have been analyzed to assess the degree of improvement in quality of the infiltrated water with respect to the tertiary wastewater used for irrigation. The data analysis indicates that in spite of low clay content of the soil, improvement in the quality of the tertiary treated wastewater through soil aquifer treatment by the removal of ammonia (>90%), iron (>80%), organic carbon (>90%), biological oxygen demand (BOD) (100%) and bacteria (50-100%, depending on its type), can be expected over a long-term period. Soil leaching, however, tends to increase the total dissolved solids of the infiltrated water and the nitrification process increases the nitrate content.