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Biomedical subjects

A Gehani

Publications and source records attributed to A Gehani.

3 recordsLinked to original sources
PubMed2004

The effect of hypertension as a predictor of risk for congestive heart failure patients over a 10-year period in a newly developed country.

AIMS: Cardiovascular disease is the leading cause of mortality and morbidity in the western world and has reached epidemic proportions. The incidence of congestive heart failure (CHD) and hypertension is also rising rapidly in many of the affluent Arab nations and cardiovascular diseases continue to be a leading cause of morbidity and mortality among adult Qataris and Asians residing in Qatar. OBJECTIVE: The objective of this study is to assess the effect of hypertension among patients admitted to hospital in Qatar with CHD and to identify risk factors that contribute to the development of CHD in hypertensive subjects. DESIGN: This is a retrospective cohort study. SETTING: Hamad General Hospital, Hamad Medical Corporation. SUBJECTS: All patients who were hospitalized with CHD with or without hypertension in the Hamad General Hospital, State of Qatar, from 1991 to 2001. METHODS: The diagnostic classification of definite CHD was made in accordance with criteria based on the International Classification of Disease, ninth revision (ICD-9]. RESULT: A total of 20,856 patients were treated during the 10-year period; 8446 were Qataris. Among them, 60% were males and 40% females. Among the total patients (3713) hospitalized with CHD, 1744 (46.9%) had hypertension. Furthermore, the incidence of hypertension was slightly higher in males than in females (56.4 vs 43.6%). A statistically significant difference was found between hypertensive and non-hypertensive cases with diabetes mellitus and angina. Hypertensive subjects were more likely to have diabetes (p < 0.001) and angina (p < 0.030). The mortality rate of CHD patients with hypertension was higher among Qataris than among non-Qataris (p < 0.038). CONCLUSION: Hypertension was the most common risk factor for CHD; it contributed a large proportion of heart failure cases in this population-based sample. Preventive strategies directed toward earlier detection of elevated blood pressure and its control are likely to offer the greatest promise for reducing the incidence of CHD and its associated mortality.

Adult↗
PubMed1999

Micro flow bio-molecular computation.

In this paper we provide a model for micro-flow based bio-molecular computation (MF-BMC). It provides an abstraction for the design of algorithms which account for the constraints of the model. Our MF-BMC model uses abstractions of both the recombinant DNA (RDNA) technology as well as of the micro-flow technology and takes into account both of their limitations. For example, when considering the efficiency of the recombinant DNA operation of annealing, we take into account the limitation imposed by the concentration of the reactants. The fabrication technology used to construct MEMS is limited to constructing relatively thin 3D structures. We abstract this by limiting the model to a small constant number of layers (as is done with VLSI models). Besides our contribution of the MF-BMC model, the paper contains two other classes of results. The main result is the volume and time efficient algorithm for message routing in the MF-BMC model, specifically useful for PA-Match. We will show that routing of strands between chambers will occur in time O(N x D/ m x n), where N is the number of strands in the MF-BMC, n is the number of chambers where RDNA operations are occurring, D is the diameter of the topology of the layout of the chambers, and m is proportional to the channel width. Operations that need annealing, such as PA-Match, are shown feasible in O(N2logN/n/n) volume instead of the previous use of omega(N2) volume, with reasonable time constraints. Applications of the volume efficient algorithm include the use of the Join operation for databases, logarithmic depth solutions to SAT (Boolean formula satisfiability) problems and parallel algorithms that execute on a PRAM. Existent algorithms can be mapped to ones that work efficiently in the MF-BMC model, whereas previous methods for applications such as PRAM simulation in BMC were not both time and volume efficient. Our other class of results are theoretical lower bounds on the quantities of DNA and the time needed to solve a problem in the MF-BMC model, analogous to lower bounds in VLSI. We bound the product BT from below, and further show that BT2 has a stronger lower bound of I2. Here B is the maximum amount of information encoded in the MF-BMC system at a time. T is the time for an algorithm to complete, and I is the information content of a problem.

Animals↗