الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Hepatitis C Virus (HCV) is a health problem worldwide. The World Health Organization estimates that 3% of world’s population is infected with HCV. The virus is a small (50 nm), single-stranded RNA virus that belongs to the Flaviviridae family, perhaps surprising to know that the hepatitis C virus replicates rapidly and can provide about 10 trillion copies of virus per day.
Hepatitis C virus (HCV) has become an endemic in Egypt. The country has a uniquely high HCV prevalence worldwide. There are many estimates that are trying to determine the number of Egypt’s population living with HCV. Genotype 4 of the virus is the most common in Egypt and the Middle East. Several studies indicate that more than 15% of Egypt’s population are infected with the virus. This percentage is much larger than any other country and become the most important problem in the country.
There are six different major genotypes and more than 50 subtypes of HCV with varying presence in different parts of the world. Genotypes don’t influence the severity of the disease but do affect in the treatments (example: Genotype 1 respond less to viral therapy than genotypes 2 and 3.
The following methods and tests are currently used in the survey of hepatitis C virus:
• Measurement of hepatic enzymes
• HCV antibodies(Elisa)
• Detection of Virus DNA(Real-Time PCR)
• HCV genotyping
• Liver biopsy
An electronic nose is a device use to perceive odors or flavors, likewise the human olfactory system, as a global fingerprintwhich consists of three essential elements: an array of olfactory receptor cells situated in the roof of the nasal cavity, the olfactory bulb which is situated just above the nasal cavity; and the brain.
In an e-nose there are three components; a) a sampling conditioning unit, which delivers the odor volatiles from the headspace above the sample; b) a test chamber in which the sensor array is based; and c) a processing unit which analyzes the sensor responses for pattern recognition.
Organic volatilized molecules that pass over this array variably bind with sensors, producing a change in conformation and a resulting change in the conductivity across the sensor. The use of an array of such nonspecific sensors allows for the relative responses among the sensors to be used to produce a unique odor profile or fingerprint of an odor. The odor profile can then be further analyzed using pattern recognition techniques (e.g., principal components analysis, discriminant function analysis, factor analysis) and structural algorithms (e.g., neural network analysis)
Recently, the e-nose has been applied for detecting odor chemistry of underivatized human blood through the identification of the more volatile and primarily odor producing chemicals of blood, which are large numbers of molecular chains involving amino acids.
In our current study, we applied the e-nose technology to measure qualitative odor differences of blood samples from apparently healthy donors in comparison with those with viral hepatitis C in the asymptomatic and proven phases of the disease.
We found that the results of applying principle component analysis (PCA) to the all study groups as the following:
from the figures: Fig. (17) shows Cluster plot of E- Nose sensor response for anti-HCV around cut-off group (n = 23), Fig. (18) shows Cluster plot of E- Nose sensor response for Confirmed HCV group (n = 14), Fig. (19) shows Cluster plot of E- Nose sensor response for Healthy control group (n=48), Fig. (20) shows Cluster plot of E- Nose sensor response for the three groups: Around cut-off HCV group (n=23), Confirmed HCV group (n=14), Healthy control group (n=48). we can observe a significant differentiation among the control group, confirmed HCV group and around cut-off group specially those clusters with average higher viral loads.
from figure. (21) which shows Plot of principle component #1 against principle component #2 for an array of 10 Metal-oxide sensors based-electronic nose when applied to headspace of samples for healthy control group (n=48), Confirmed HCV group (n=14), we can appreciate the clear discrimination between the control group and the Confirmed chronic HCV group which the overlap (intersection) of some clusters may reflect average lower viral load in some patients.
Finally we found that the electronic nose equipment showed an appreciated sensitivity and specificity in distinguishing around cut-off individuals, confirmed (Proven) HCV patients as compared to healthy control group. Moreover the equipment was successfully differentiated healthy controls with higher degree of precision from the other pathologic groups. Thus in addition for its robustness, simplicity, sensitivity, and cost-effectiveness the electronic nose represents a novel significant diagnostic significant diagnostic tool.
We recommended using e-nose for:
• Blood bank donors screening: taking the advantage of e-nose simplicity, time and cost effectiveness of the device including the significant sensitivity (85.71%) obtained in distinguishing patients with chronic HCV, e-nose is suggested to be a promising HCV diagnostic tool candidate for blood bank donors and mass screening.
• Surveys/campaigns: The portability and fast time-to-result with the interesting accuracy of the tool explored in this thesis, enables a proactive screening search for HCV cases in rural areas, without the need for highly-skilled operators or a hospital centre infrastructure. This advantage can provide an interesting feature to nations especially developing countries with high HCV prevalence such as Egypt in surveying HCV infected cases for distant rural areas with limited facilities and efforts in controlling the disease.