3,695 research outputs found
Prognostic significance of COX-2 and b-catenin in colorectal carcinoma
Background: The high prevalence of colorectal carcinoma (CRC) is a driver to understand the underlying molecular mechanisms. Chemoprevention strategy using non-steroidal antiinflammatory drugs (NSAIDs) revealed that these drugs suppress colorectal carcinoma. The best known targets of NSAIDs are cyclooxygenase (COX) enzymes. The function of prostaglandins and cyclooxygenase in cancer pathogenesis is unclear. COX-2 regulation of proliferation, apoptosis, and tumor-blood vessel interaction has been suggested. b-Catenin is a component of the WNT (wingless type) signaling pathway, increased protein concentrations promote transcription of genes important in regulating the cell cycle.Aim: To determine the significance of COX-2 and b-catenin expression in colorectal carcinogenesis and prognosis.Patients and methods: Thirty patients with colorectal carcinomas treated by colonic resection were studied for the expression of both COX-2 and b-catenin by immunohistochemistry. Their expression was interpreted in relation to adjacent normal colonic mucosa and analyzed in correlation with various clinicopathologic parameters and patient’s survival after a follow up period of 24 months.Results: Our results showed that in normal adjacent colonic mucosa, COX-2 was completely absent, whereas b-catenin was specifically located in the plasma membranes. Both proteins were expressed in tumorous tissues, COX-2 showed diffuse cytoplasmic positivity, whereas b-catenin accumulated in both the cytoplasm and nuclei. We established statistically significant relationships between pathological grade and both b-catenin, and COX-2 positivity scores, being at the higher end for poorly-differentiated tumors. b-Catenin expression also correlated significantly with higher tumor stage and LN metastasis. Both COX-2 and b-catenin expression correlated with a higher incidence of shorter disease free survival.Conclusion: Both b-catenin and COX-2 expression may play an important role in the evolution of colon carcinogenesis. Increased expression of both could be used as a marker of tumor progression and poor prognosis. This might be of therapeutic value for allocating patients with colorectal carcinoma to different treatment modalities.Keywords: b-Catenin COX-2 Colorectal carcinoma Immunohistochemistry Prognosi
Optical signatures of intrinsic electron localization in amorphous SiO2
We measure and analyse the optical absorption spectra of three silica glass samples irradiated with 1 MeV electrons at 80 K, where self-trapped holes are stable, and use ab initio calculations to demonstrate that these spectra contain a signature of intrinsic electron traps created as counterparts to the holes. In particular, we argue that optical absorption bands peaking at 3.7, 4.7, and 6.4 eV belong to strongly localised electrons trapped at precursor sites in amorphous structure characterized by strained Si–O bonds and O–Si–O angles greater than 132°. These results are important for our understanding of the properties of silica glass and other silicates as well as the reliability of electronic and optical devices and for luminescence dating
On the Consistency of the Solutions of the Space Fractional Schr\"odinger Equation
Recently it was pointed out that the solutions found in literature for the
space fractional Schr\"odinger equation in a piecewise manner are wrong, except
the case with the delta potential. We reanalyze this problem and show that an
exact and a proper treatment of the relevant integral proves otherwise. We also
discuss effective potential approach and present a free particle solution for
the space and time fractional Schr\"odinger equation in general coordinates in
terms of Fox's H-functions
Geophysical investigations of a geothermal anomaly at Wadi Ghadir, eastern Egypt
During regional heat flow studies a geothermal anomaly was discovered approximately 2 km from the Red Sea coast at Wadi Ghadir, in the Red Sea Hills of Eastern Egypt. A temperature gradient of 55 C/km was measured in a 150 m drillhole at this location, indicating a heat flow of approximately 175 mw/sqm, approximately four times the regional background heat flow for Egypt. Gravity and magnetic data were collected along Wadi Ghadir, and combined with offshore gravity data, to investigate the source of the thermal anomaly. Magnetic anomalies in the profile do not coincide with the thermal anomaly, but were observed to correlate with outcrops of basic rocks. Other regional heat flow and gravity data indicate that the transition from continental to oceanic type lithosphere occurs close to the Red Sea margin, and that the regional thermal anomaly is possibly related to the formation of the Red Sea
Simulation: Early Detection of Brain Vessels Stroke by Applying Electromagnetic Waves Non-Invasively
Introduction: Early recognition of stroke with its two types Ischemic and Hemorrhagic, is one of the most crucial research points, commonly used methods are CT- (computerized tomography), and MRI- (Magnetic resonance imaging). These techniques cause a delay in the detection of the condition, which causes permanent disability. The main reason behind the fatal consequences of stroke is the delay of detection. Therefore, this research paper aims to early detection of the type of stroke without delay until the appropriate diagnosis of each type is made, and then the appropriate treatment without delay.
Method: Using a non-invasive and fast technique to determine the stroke type by wave, we simulate and design a vessel containing a liquid as a laminar flow with the same density and velocity of blood, and it was surrounded by a Homogenized multi-turn coil consisting of (n) turns to represent the magnetic field, using specific frequency (HZ) with Electrical field in coil current (A) to see the changing in magnetic flux density (MFD), Depending on the changes in MFD, the flow of blood in laminar flow can be affected by clotting (Ischemic) or Hemorrhagic (cutting) in our vessel designed. We have built three different scenarios to apply the technique which are: First: Normal Scenario (where the blood in vessel has no problem), second: clotting (ischemic, where the vessel blocked in specific three position) and Third: Cutting (Hemorrhagic, where the vessel cut in certain nine positions).
Results: This paper presents-through our own design-the studying of applying the electromagnetic waves on blood inside the vessel to detect the stroke type in our three scenarios (normal, ischemic three positions or hemorrhagic nine positions), Studying the magnetic field and laminar flow. This study covered in three areas. First: coil geometry analysis, Second: stationary, and Third: frequency domain. through the changes in Magnetic Flux Density -MFD- waves. The results were promising and distinct for distinguishing between the three scenarios which are normal, ischemic (3 positions) and hemorrhagic (9 positions) the results of MFD are: 0.09 to 3.3*10^-3, 0.08 to 3.15*10^-4, 0.15 to 6.2*10^-3 respectively
The association between right ventricular function and exercise capacity for hypertensive patients
Background: Transthoracic echocardiography (TTE) would be used to evaluate right ventricular (RV) function in patients with arterial hypertension, and the link between RV dysfunction and exercise capacity was studied in the study population.Objective: To establish a correlation with exercise capability in the study group by using transthoracic echocardiography (TTE) to evaluate RV function in patients with arterial hypertension.Patients and Methods: Patients with hypertension were surveyed in a cross-sectional research; those known and treated; whether controlled or not and patients who were recently discovered to be hypertensive. Ninety patients were included; gender and age were taken into account. A thorough examination was performed on each patient (TTE) as well as six minute walking distance (6MWD). For all we had a written informed consent prior to enrollment. Results: Patients with untreated and uncontrolled hypertension showed significantly reduced right ventricular systolic and diastolic functions compared to those with well-controlled hypertension. Patients with untreated or uncontrolled hypertension had significant (P <0.001) deterioration on S', wave and diastolic dysfunction parameters (E/A, DTt, E/e t and IVRT). Untreated and uncontrolled hypertension patients showed a significant decrease in 6MWD compared to the well-controlled individuals (P <0.001). Conclusion: Untreated or ineffectively treated hypertension individuals had considerably reduced right ventricular function and exercise capacity, according to our findings. In the entire research population, right ventricular functions are strongly linked to exercise ability
A Novel Approach in Pigment Printing Using Nano-keratin Based Binder
This study is devoted to preparation and characterization of nano-keratin based binder (NKBB) from cheap renewable natural resources, namely coarse Egyptian wool or feather. The prepared NKBB is utilized as a biodegradable, environment-friendly and relatively cheap binder in textile pigment printing of polyester, pure polyacrylic, viscose, polyester/viscose, and polyester/acrylic fabrics. Different concentrations of the prepared NKBB as well as its mixture with commercially produced one are used in the pigment printing paste. The colour strength of the printed fabrics as well as their fastness properties to light, washing, and perspiration are evaluated. The effect of the used binder on the bending stiffness of the printed fabrics is also assessed. Results show that the NKBB gives almost the same colour strength and fastness properties as the commercial binder with improved stiffness of the printed samples in relation to that printed with commercial one
Effect of casting practice on the reliability of Al cast alloys
The properties of aluminium castings are strongly affected by their inclusion content, particularly entrained surface alumina films. These form due to the surface turbulence associated with mould filling, which causes the oxidised surface of a liquid metal to fold-over onto itself and be submerged into the bulk liquid with a thin layer of air entrapped within it. This is known as entrainment action. These flaws have been reported to increase the variability of the fracture strengths of Al alloy castings. This means that shape castings in light alloys can have inconsistent properties, which makes designing structures employing shape castings more difficult. Entrained surface layers can cause premature failure, but also have been associated with other defects, such as hydrogen porosity, shrinkage porosity, intermetallic compounds and hot tearing. Recent research has suggested that the air inside the defect would react with the surrounding melt leading to its consumption, which may enhance the mechanical properties of the casting. In this work, liquid aluminium was poured into three identical ceramic moulds which were immediately placed in a furnace to preserve the molten metal at 800 C, for different periods of time prior to freezing. The Weibull moduli of the plate castings were determined under tensile conditions, and their fracture surfaces examined using SEM. Investigation of the fracture surfaces of the specimens detected many alumina layers at different locations. Many of which were found inside pores, reflecting the role of entrained defects in the formation of porosity. The results also suggested that opposite phenomena may take place during the holding treatment. The consumption of air inside the entrained defects due to reaction with the surrounding molten metal may lead to improvements in mechanical properties, but this may be accompanied by hydrogen passing into the defects, which has a deleterious effect on properties
Knowledge and practice of folic acid supplementation and impact of income level on awareness among women of child-bearing age in Saudi Arabia
Purpose: To investigate the knowledge of Saudi women (pregnant and non-pregnant) about the significance of folic acid (FA) supplementation and to determine how income levels affects this knowledge and its implementation.
Methods: The study was conducted among women of child-bearing age attending Al-Hada Armed Forces Hospital and Khaliss General Hospital (both in Riyadh, Saudi Arabia) for pregnant women and Omm Al-Qura University in Makkah Governorate (Saudi Arabia) for non-pregnant women. A structured questionnaire was used to collect socio-demographic data and to analyze levels of FA knowledge, including general awareness, proper timing of its use, information source, FA benefits, and the perils of FA deficiency. A chi-square test was performed to test the differences between variables.
Results: Analysis of the survey data revealed that 81.1 % of non–pregnant and 91.1 % of pregnant women were aware of the term, FA (p < 0.05). Moreover, 71.1 % of the pregnant compared to 35.6% of non-pregnant women knew that this supplement must be taken before becoming pregnant and this difference was statistically significant (p < 0.05). For pregnant women, doctors and previous pregnancies were the main sources of FA knowledge, while mass media was the most frequently reported source for non-pregnant women (p < 0.05). Income level was not associated with FA knowledge in either group.
Conclusions: This study illustrates a deficiency in the knowledge and consumption of this important micronutrient in women of childbearing age, the population most in need of this information. Nutrition education should be provided to increase the understanding and practice of FA supplementation periconceptionally and during pregnancy
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