Phase equilibrium studies of or anometallic chelates for analytical application

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Multifunctional Polymeric Enveloped Nanocarriers: Targeting Extracellular and Intracellular Barriers

Over the past several years, employment of multifunctional polymeric excipients-based nanoparticles for controlled and targeted drug delivery of therapeutic modalities to mucosal membrane-based organelles and systemic circulation has gained enormous interest. Because they promise to resolve numerous key therapeutical issues associated with current clinical practice including low treatment efficacy and significant side effects. Potential controlled and targeted drug delivery systems, therefore, should be able to overcome not only extracellular barriers but also intracellular barriers. Extracellularly, targeted nanocarriers ought to provide extended circulation time, selective binding to the targeted mucosal tissues, long residence time at the site of absorption, and controlled drug release. Intracellularly, the targeted nanocarriers should offer cellular uptake, cellular localization, and endosomal release. Hence, this chapter will provide an overview of the unique chemistry of multifunctional polymeric enveloped diverse nanocarriers such as dendrimers, semiconducting polymer dots, quantum dots, carbon dots, and magnetic as versatile platform addressing both extracellular and intracellular barriers

Evidence of son preference and resulting demographic and health outcomes in Pakistan

Pakistan has a highly patriarchal society. Consequently, the desire for sons is a dominant and widely prevalent cultural value that is reinforced by feudal kinship systems that permeate many parts of the country. While reliance on sons is stronger in rural areas because of agricultural work and the tying of land ownership with male inheritance, even in other areas boys are seen to be important in carrying on the family name and taking care of parents in old age. On the other hand, daughters are seen as an expense and an economic burden in both rural and urban areas. A mere 22 percent of women participate in the labor force, and the role of women as productive agents is largely confined to urban areas. The majority of women remain economically dependent on male household members and are unlikely to be contributing to household income. Preference for sons can translate into sex-selective abortions and uneven sex ratios at birth. This report forms part of a research project to explore the issue of gender-biased sex selection and to make evidence-based recommendations for responding to adverse sex ratios at birth

Ultimate strength design of perforated deep beams

The design of deep beams with or without openings is not yet covered by the new British Code CP110 (1972). The CIRIA guide does contain some design guidance for solid deep beams but the design of deep beams with openings is only briefly covered. In both cases the design procedures follow an empirical approach. The current trend in reinforced concrete design is towards the ultimate limit state methods. In recent years proposals have been made for a more rational approach to reinforcement design for in-plane forces. For a given ultimate load, a stress field in equilibrium with external loads is obtained by a linear elastic stress analysis, e.g. finite element analysis. Reinforcement is provided such that the combined resistance of steel and concrete at every point is equal to or greater than the applied stresses. If the equilibrium and yield criteria are satisfied exactly at every point then the entire structure will be converted to a mechanism at ultimate load. In order for this to happen the structure should have sufficient ductility so that redistribution of stresses takes place as cracking occurs. This thesis is concerned with an experimental study of the proposed design method applied to deep beams with openings and in general with the effect of the opening on beam behaviour. The test series comprised of seven specimens of deep beams with and without an opening having different concrete strengths and varying span to depth ratios. The effects of an opening on/ deflections, crack widths, crack patterns, failure mode and ultimate shear strengths were studied. All the beams were simply supported and under two concentrated top loads except one. The beams were loaded in increments without unloading until collapse occurred. The test results indicate that the ultimate loads were higher in beams where an opening is near the beam soffit than in beams where an opening is at mid-depth. In all the tests the experimental ultimate load greatly exceeded the design load. Why this is so is discussed and by using an empirical factor experimental ultimate load predictions are improved. Further analytical and experimental study is recommended

Comparative metal distribution in scalp hair of Pakistani and Irish referents and diabetes mellitus patients

Background: The essential metals, chromium (Cr), magnesium (Mg), manganese (Mn) and zinc (Zn), are necessary for many metabolic processes and their homeostasis is crucial for life. The toxic metals, cadmium (Cd) and lead (Pb), have no beneficial role in human metabolism. The aim of this study was to investigate the levels of Cd, Cr, Mg, Mn, Pb, and Zn in scalp hair samples of type 2 diabetes mellitus patients of both genders, ages ranging from 30 to 50 y, and belong to urban areas of Ireland and Pakistan. For comparison purposes, age matched non-diabetic subjects of both countries were selected as referents. Methods: The concentrations of metals in scalp hair samples were measured by inductively coupled plasma atomic emission spectrophotometer and atomic absorption spectrophotometer after microwave-assisted acid digestion. The validity and accuracy of the methodology were checked by conventional wet-acid-digestion method and using certified reference materials. Results: The mean values of Cd and Pb were significantly higher in scalp hair samples of both Pakistani and Irish diabetic patients as compared to referents of both countries (P<0.001). In contrast, lower Cr, Mg, Mn, and Zn (P<0.01) concentrations were detected in scalp hair derived from patients with type 2 diabetes versus healthy subjects of both countries. Conclusion: This study showed that, increased toxic elements and decreased essential elements are associated with diabetes mellitus. Therefore, these elements may play a role in the development and pathogenesis of diabetes mellitus

Evaluation of essential trace and toxic elements in scalp hair samples of smokers and alcohol user hypertensive patients

The incidence of hypertension has been associated to cigarette smoking and consumption of alcohol. In the present study, trace and toxic elements were determined in scalp hair of patients diagnosed with hypertension who are smokers and habitual alcohol drinkers living in Dublin, Ireland. These results were compared with age- and sex-matched healthy, nonsmokers, nondrinking controls. The concentrations of trace and toxic elements were measured by inductively coupled plasma atomic emission spectrophotometer after microwave-assisted acid digestion. The validity and accuracy of the methodology were checked using certified reference material (NCS ZC 81002b) and by the conventional wet acid digestion method on the same certified reference material and on real samples. The recovery of all the studied elements was found to be in the range of 97.5%–99.7% in certified reference material. The results of this study showed that the mean values of cadmium, copper, iron, nickel and lead were significantly higher in scalp hair samples of both smoker and nonsmoker hypertensive patients than referents (P < 0.001); whereas, the concentration of zinc was lower in the scalp hair samples of hypertensive patients of both genders. The deficiency of zinc and the high exposure of trace and toxic metals as a result of cigarette smoking and alcohol consumption may be synergistic with risk factors associated with hypertension

Interaction between essential trace and toxic elements in the scalp hair samples of smokers and alcohol user diabetics

In the present study, trace and toxic elements were determined in the Scalp Hair (SH) samples of patients diagnosed with diabetes mellitus (DM) who were smokers and habitual alcohol drinkers living in Dublin, Ireland. The concentrations of elements were measured by inductively coupled plasma atomic emission spectrophotometer after microwave-assisted acid digestion. The validity and accuracy of the methodology was checked using Certified Reference Material (CRM) (NCS ZC 81002b) and by the conventional wet acid digestion method on the same CRM. The results of this study showed that the mean values of cadmium, copper, iron, nickel and lead were significantly higher (P<0.001), in scalp hair samples of diabetic patients as compared to referents of both gender. While the smokers and alcohol drinker referents and DM patients have two to three time higher values of these elements than those subjects who were not smokers and teetotallers. The concentrations of zinc, chromium and manganese were lower in the scalp hair samples of diabetic patients as compared to referents. The deficiency of zinc, chromium and manganese, while the high exposure of cadmium, lead and nickel, as a result of cigarette smoking and alcohol consumption, may be synergistic with risk factors associated with diabetes

Interaction between zinc, cadmium, and lead in scalp hair samples of Pakistani and Irish smokers rheumatoid arthritis subjects in relation to controls

The incidence of rheumatoid arthritis (RA) has been associated with cigarette smoking. The aim of our study was to assess the trace essential and toxic metals, cadmium (Cd), lead (Pb), and zinc (Zn), in scalp hair samples of 32 Irish and 46 Pakistani smokers and non-smokers RA male patients with age range 42-56 years. For comparison purpose, the scalp hair samples of 27 Irish and 55 Pakistani non-RA male subjects of the same age group were collected. The concentrations of trace and toxic elements were measured by inductive coupled plasma atomic emission spectrophotometer and atomic absorption spectrophotometer prior to microwave-assisted acid digestion. The validity and accuracy of the methodology was checked using certified reference materials and using conventional wet acid digestion method on the same certified reference materials (CRMs). The recovery of all studied elements was found to be in the range of 97.5-99.7% of certified reference values of CRMs. The results of this study showed that the mean values of Cd and Pb were significantly higher in scalp hair samples of both smoker and non-smoker RA patients than in referents (P < 0.001), whereas the concentration of Zn was lower in the scalp hair samples of smokers and non-smokers rheumatoid arthritis patients. The deficiency of Zn and the high exposure of Cd and Pb as a result of cigarette smoking may be synergistic risk factors associated with rheumatoid arthritis

Estimation of toxic elements in the samples of different cigarettes and their effect on the essential elemental status in the biological samples of Irish smoker rheumatoid arthritis consumers

Cigarette smoking interferes with the metal homeostasis of the human body, which plays a crucial role for maintaining the health. A significant flux of heavy metals, among other toxins, reaches the lungs through smoking. In the present study, the relationship between toxic element (TE) exposure via cigarette smoking and rheumatoid arthritis incidence in population living in Dublin, Ireland, is investigated. The trace {zinc (Zn), copper (Cu), manganese (Mn), and selenium (Se)} and toxic elements arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) were determined in biological (scalp hair and blood) samples of patients diagnosed with rheumatoid arthritis, who are smokers living in Dublin, Ireland. These results were compared with age and sex-matched healthy, nonsmoker controls. The different brands of cigarette (filler tobacco, filter, and ash) consumed by the studied population were also analyzed for As, Cd, Hg, and Pb. The concentrations of trace and TEs in biological samples and different components of cigarette were measured by inductively coupled plasma mass spectrophotometer after microwave-assisted acid digestion. The validity and accuracy of the methodology were checked using certified reference materials. The recovery of all the studied elements was found to be in the range of 96.4–99.8 % in certified reference materials. The filler tobacco of different branded cigarettes contains Hg, As, Cd, and Pb concentrations in the ranges of 9.55–12.4 ng, 0.432– 0.727 μg, 1.70–2.12 μg, and 0.378– 1.16 μg/cigarette, respectively. The results of this study showed that the mean values of As, Cd, Hg, and Pb were significantly higher in scalp hair and blood samples of rheumatoid arthritis patients as compare to healthy controls, while Zn, Cu, Mn, and Se concentrations were found to be lowerin rheumatoid arthritis patients, the difference was significant in the case of smoker patients (p<0.001). The levels of four toxic elements were 2–3-folds higher in scalp hair and blood samples of nonrheumatoid arthritis smoker subjects as compared to nonsmoker controls. The high exposure of toxic metals as a result of cigarette smoking may be synergistic with risk factors associated with rheumatoid arthritis