Études des interactions entre la mucine et certains polymères bioadhésifs

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal

Determination of heavy metals uptake by acacia Mangium grown in ex-mining area in Kg Gajah, Perak / Nor Fadilah Chayed

Heavy metals content of chromium, copper, iron, lead, and nickel in Acacia mangium in a former iron and tin mining land at Kampung Gajah, Perak were determined. Heavy metals content were determined in three plant component namely roots, stems and leaves. 19 Acacia mangium plants were collected for analysis from twelve different locations. The heavy metals content in plants sample were extracted by using wet digestion method using the mixture of nitric acid and hydrogen peroxide. Heavy metals content in solution extract of plant sample were determined with Flame Atomic Absorption Spectrometer. The analyses indicate that the concentration of iron in the plant sample is the highest followed by chromium, copper, lead and nickel. Roots show highest content of heavy metals followed by leaves and finally the stems. As expected, those location which contained higher levels of heavy metals which is near to the mine area showed to have higher heavy metals uptake by various parts of Acacia mangium. These data demonstrate Acacia mangium’s ability to uptake heavy metals such as chromium, copper, iron, lead and nickel from ex-mining area. COPYRIGHT

Synthesis and characterization of MgO nanostructures by different synthesis methods / Nor Fadilah Chayed

Magnesium oxide (MgO) is an interesting material and has unique properties which is applicable in many applications. In this research, novel MgO nanostructures o f ultra-thin sheets were synthesized using three different synthesis methods which are solid-state reaction, sol-gel and combustion methods. The synthesis condition was optimized to obtain pure MgO compound. These pure samples were characterized using Simultaneous Thermogravimetric Analyzer (STA), X-Ray Diffraction (XRD), High Resolution Transmission Electron Microscopy (HRTEM) and UV-Vis spectroscopy. The results shows pure MgO nanostructures can be obtained at the temperature of 600 °C for all synthesis methods that gives the ultra-thin nano sheets as can be seen from high resolution TEM. Different synthesis methods can give surprisingly the same morphology but in different thicknesses. However, combustion method gives the thinnest nanosheets followed by the sol gel and solid-state reaction methods. The band gap energy obtained for MgO samples synthesized by all methods have values of 5.825 eV to 5.955 eV which are much lower than the MgO bulk value of 7.8 eV. The characteristics of the band gap change with annealing time are different for the samples prepared by different preparation process. Therefore, the band gap energies o f MgO nanostructures are sensitive to the different synthesis methods. Results show that the band gap energies of nanostructures can be tuned to a suitable value needed for various applications by controlling the annealing time. Solgel method is the best method for producing MgO nanostructures at a temperature of 600 °C and at the shortest possible time of 1 h and also capable of producing large amounts of final product compared to the other methods

The Role of Foreign Investment in the Development of Financial Markets (Iraq Stock Exchange for the period 2010 – 2017)

The research aims to show the role of financial markets in providing the necessary funds for the development of the national economy by attracting foreign investment.   Financial markets have played a major role in the global economy. The importance of these markets in the role played by the financing of the local economy by working on the convergence between groups that suffer from the financial deficit, and those who have the financial surplus and seeks to employ this money. The economic scene has witnessed many changes, including economic globalization, which has become a major challenge to the global economies, and the most important manifestations, the liberalization of financial markets and the increase of capital flows, so took many countries, including developing countries interested in attracting foreign investment and benefit from the movement of international capital, To the role of foreign capital in activating financial markets and their reflection in economic development. The research was conducted in the Iraqi Stock Exchange for the period 2010-2017. The research reached a number of conclusions, the most prominent of which was that the decline in oil prices in 2014 affected the movement of foreign and domestic funds in the financial market. The research also reached a number of recommendations, the most important of which is to develop the legal environment that allows registered and new companies in the stock market to increase their capital in order to attract domestic and foreign investments. Keywords : Foreign Investment, Development of Financial markets.

Hereditary leiomyomatosis and renal cell cancer

Hereditary leiomyomatosis and renal cell cancer is a genodermatosis with an autosomal dominant inheritance pattern. It is a tumour predisposition syndrome characterized by cutaneous and uterine leiomyomas, and increased susceptibility to develop renal cell carcinoma. There are 200–300 families with hereditary leiomyomatosis and renal cell carcinoma reported worldwide, but the syndrome is believed to be underdiagnosed. Cutaneous leiomyomas are small smooth muscle tumours that tend to grow over time. Larger lesions, in particular, can cause pain or itching. Uterine leiomyomas have a high penetrance in women with hereditary leiomyomatosis and renal cell cancer. They frequently cause symptoms, and surgical intervention is often necessary. Hereditary leiomyomatosis and renal cell cancer-associated renal cell carcinomas have a high potential to metastasize. Patients are diagnosed by genetic testing if a pathogenic mutation is demonstrated in the gene encoding fumarate hydratase. Immunohistochemistry may be a useful diagnostic approach in patients without a detectable pathogenic mutation. Diagnosed patients should be monitored for renal tumours in a lifelong surveillance programme.</p

BioFire blood culture identification 2 panel as detector of bacteria in peritoneal fluid from patients with acute appendicitis

Background: Polymerase chain reaction is a method to detect bacterial DNA and is widely used because it delivers results within a few hours with the potential to guide postoperative antibiotic treatment. This study aims to determine if polymerase chain reaction can accurately detect bacteria in the peritoneal fluid compared with conventional culture from patients operated for acute appendicitis. Methods: This prospective cohort study included patients above the age of 18 years who underwent laparoscopic surgery for acute appendicitis. Peritoneal samples were collected before the appendectomy procedure for conventional culture and polymerase chain reaction using the BioFire Blood Culture Identification 2 Panel for comparison. During surgery, the surgeon assessed the appendicitis as either complicated or noncomplicated. Results: Samples from 102 patients were eligible for analysis. Twelve samples were polymerase chain reaction positive, and 14 samples were culture positive. The concordance of positive results when comparing these 2 methods was 71.4%. The most commonly found bacteria were Escherichia coli and Bacteroides fragilis. Of the 36 patients with complicated appendicitis, no bacteria were detected by either conventional culture or polymerase chain reaction in 21 (58%) of the patients. In patients with uncomplicated appendicitis, bacteria were demonstrated in 1 out of 66 (2%) patients. Conclusion: This study suggests that polymerase chain reaction can be used to detect bacteria in the peritoneal fluid and has the potential to guide postoperative antibiotic treatment.</p

Hereditary leiomyomatosis and renal cell carcinoma:a case series and literature review

BACKGROUND: Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) is a rare genodermatosis characterized by cutaneous leiomyoma (CLM), uterine leiomyoma (ULM) and renal cell carcinoma (RCC). Five HLRCC patients are presented with a compiled database of published HLRCC cases to increase understanding of HLRCC. Furthermore, a surveillance program is suggested. Our review is based on a PubMed search which retrieved case reports and cohort studies published before November 2019. The search yielded 97 original papers with a total of 672 HLRCC patients.RESULTS: CLMs were present in 474 patients (71.5%), developed at the mean age of 28 years. Five patients had cutaneous leiomyosarcomas. ULMs were present in 356 women (83%), while two had uterine leiomyosarcoma. ULMs were diagnosed at a mean age of 32 years, with the youngest diagnosed at age 17 years. The most common surgical treatment for ULMs was hysterectomy, performed at a mean age of 35 years, with the youngest patient being 19 years old. RCCs were present in 189 patients (34.9%), of which half had metastatic disease. The mean age of diagnosis was 36 years with the youngest patient diagnosed with RCC at the age of 11 years.CONCLUSION: We suggest a surveillance program for HLRCC including a dermatological examination once every 2 years, annual magnetic resonance imaging starting at the age of 10 years to monitor for early RCCs, annual gynecological examinations from the age of 15 years and counseling regarding risk of hysterectomy and family planning at the age of 18 years. CLMs are often the earliest manifestation of HLRCC, which is why recognizing these lesions, performing a biopsy, and making a prompt referral to genetic counseling is important in order to diagnose HLRCC early.</p

HISTOPATHOLOGICAL STUDY OF PULMONARY LESIONS IN THE LUNGS OF WATER BUFFALOES (Bubalus bubalis) IN THE ABATTOIR OF BASRAH PROVINCE IN SOUTHERN IRAQI

Water Buffalo (Bubalus bubalis) is one of the important animals in Iraq becauseof its great economic value and historical symbolism, which reflects the history and thecivilisation epoch of Mesopotamia. This study has focused on the macroscopic lesionsthat appear on the lungs of the water buffaloes with also an examination of thesespecimens microscopically, which reflect the extent of pulmonary disease among theseanimals, which form significant economic losses. This study was conducted in theabattoir of Basrah province, south of Iraq, from October 2019 until February 2020.Samples of 120 affected lungs (23.21%) of different macroscopic lesions were obtainedof the total 517 water buffaloes. The microscopic lesions were divided into the following:bronchopneumonia 29 cases (24.17%) (Suppurative bronchopneumonias 14 cases(48.28% out of 29) and fibrinous bronchopneumonias 15 cases (51.72%). The interstitialpneumonia was 33 cases (27.5%)(Acute Interstitial pneumonia 21 cases (63.64% out of33) and chronic interstitial pneumonia was 12 cases (36.36%), granulomatous pneumonia5 cases (4.17%), emphysema 18 cases (15%), atelectasis 7 cases (5.83%), oedema cases 5(4.17%), congestion 6 cases (5%), haemorrhage 11 cases (9.16%), pneumoconiosis(anthracosis) 6 cases (5%). Pneumonia in water buffalo is the most challenging conditionto treat after it has worsened. Hence, regular veterinary examination and testing is anessential step in managing the disease as it has become unreactive to therapies in the laterstage

Methods to determine the interactions of micro- and nanoparticles with mucus

The present review provides an overview of methods and techniques for studying interactions of micro- and nanoparticulate drug delivery system with mucus. Nanocarriers trapped by mucus are featuring a change in particle size and zeta potential that can be utilized to predict their mucus permeation behavior. Furthermore, interactions between nanoparticulate drug delivery systems and mucus layer modify the viscoelasticity of mucus which can be detected via rheological studies and quartz crystal microbalance with dissipation monitoring (QCM-D) analysis. To have a closer look at molecular interactions between drug carrier and mucus small-angle neutron scattering (SANS) is an appropriate analysis technique. Moreover, different methods to determine particle diffusion in mucus such as the newly established Transwell diffusion system, rotating silicone tube technique, multiple-particle tracking (MPT) and diffusion NMR are summarized within this review. The explanations and discussed pros and cons of collated methods and techniques should provide a good starting point for all those looking forward to move in this interesting field

Li2xMg(1-x)O light absorption properties for semiconductor applications / Nor Fadilah Chayed … [et al.]

Substitution of cation in metal oxides could give different properties with potential in some application such as semiconductor. Li2xMg(1-x)O was prepared by substitution of magnesium with lithium in magnesium oxide to form new materials Li2xMg(1-x)O (x= 0.1, 0.2) which were Li0.2Mg0.9O and Li0.4Mg0.8O. Both MgO and Li2xMg(1-x) O were synthesized by using a sol-gel method. The sample were named M1 (MgO), M2 (Li0.2Mg0.9O) and M3 (Li0.4Mg0.8O). The samples were characterized by using X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The band gap energies of the samples were obtained from measurements using a UV-Vis Spectrophotometer. The XRD patterns of lithium substituted samples are isostructural with the ICDD pattern of MgO (ICDD No. 01-074-1225). No impurity peaks could be observed. The peak positions are slightly shifted to the right as is illustrated by the shift of the (200) reflection and this is true with the other peaks as well. This implies that the cell parameters have decreased and it can only happen if the smaller ionic radius Li+ ions have been successfully substituted into the crystal lattice of the MgO. The ionic radii of the ions, Li+ and Mg2+, are 0.76 angstrom and 0.72 angstrom respectively according to coordination number 6 (cubic structure). Therefore, lithium can be said to have been successfully introduced into the crystal lattice of the material and the substitution reaction is deemed successful. It is observed that the average crystallite size of M2 and M3 samples are much bigger than although the annealing time and temperature is the same. This shows that the thermal characteristics of the Li2xMg(1-x)O are quite different from the pure MgO. The rate of crystal growth of the materials with more lithium content is higher as can been seen with the large crystallite size of highest lithium content sample (M3). Thus, the amount of lithium content in the samples seems to affect the rate of crystal growth. It was found that there were quite drastic differences in the band energies of MgO and Li2xMg(1-x)O materials. The band gap energy for MgO is 5.13 eV which is lower than conventional value (7.8eV) by about 34%. There are two absorption edges for the Li containing samples instead of just one as observed for the MgO sample. The edges have a gradual slope and this is very different from that of the absorption edge of MgO which has a distinctly sharp edge. The positions of the absorption edges are towards the lower wavelength region and correspond to band energies of 2.82 eV and 2.90 eV for first absorption edge and 1.83 eV and 1.98 eV for second absorption edge. These very different spectra observed for the Li substituted samples is another proof of the formation of new Li0.2Mg0.9O and Li0.4Mg0.8O compounds. Materials are uniquely characterized by their band gaps. It is observed that the larger the Li content the larger the band energies. The observed red shift may be because the presence of Li may have caused hybridization and introduced more energy levels in-between the MgO gap. The substituted materials, Li2xMg(1-x)O have band gaps of between 1.83 eV to 2.90 eV which make it usable as semiconductor materials