Tumor Immunology - The Role of Tumor-Associated Macrophages Research Paper

Tumor Immunology - The Role of Tumor-Associated Macrophages - Research Paper Example Macrophages are multipurpose cells act in response to the stimulus in diverse tumors they release various macromolecules encompassing growth factors, cytokines, chemokines, and enzymes that potentially control tumor augmentation, tumor angiogenesis, tumor invasion, and tumor metastasis. Tumor-Associated Macrophages (TAM) act upon the invasive area where TAMs sway cancer cell motility, they also act on stroma and perivascular areas where they encourage metastasis and play an imperative role in avascular and perinecrotic regions so that hypoxic TAMs accelerate angiogenesis. The present article deals with the role of TAMs in promoting tumor induction and its role as anti-tumor agent and also the role of TAMs in malignancies. It is now established that tumor cells potentially block or elude the actions of TAMs at the site of the tumor. Molecules derived from tumor cells also activate TAM elevate survival as well as the proliferation of tumor cells. On the other hand, TAMs induce tumor angiogenesis through the production of mitogens, growth factors, and enzymes. Monocyte-macrophage lineage cells get polarized activated into M1 and M2 cells. An M1 form of macrophage activation encompasses IFN-ÃŽ ³ based cytokines, GM-CSF (granulocyte-macrophage colony stimulating factor), LPS and TNF. They are distinguished by IL-12, IL-23(both high), IL-10 (low) and profuse quantity of reactive oxygen and nitrogen intermediary and inflammatory cytokines. Whereas M2 is a macrophage activation as a result of IL-4, IL13, IC (Immune complexes), IL-10 as well as glucocorticoid hormones. M2 are involved in Th2 response and perform immunoregulatory functions and plays role in tumor progression.

American Geopolitical Interest Essay -- Politics International United

A Game of Strategy Mark Twain once defined the term, sphere of influence to be, â€Å"A courteous modern phrase which means robbing your neighbor—for your neighbor's benefit.† Like Twain, many claim that economic interests have caused America to rob its Southern neighbors and act in a self-seeking manner. Others claim that the ideological conviction that America altruistically acts according to its neighbor’s benefit has strongly influenced America’s international behavior. However, America, possessing a huge GDP at its disposal, a strong government, and a patriotic society realized that these assets alone could not guarantee the nation’s survival. It must be able to ensure national security as well as protect its interests abroad. Although it is true that ideology, economic welfare, as well as domestic politics all have played a significant role in U.S. foreign policy, the fundamental factor that has governed American foreign policy has been geopolitical objectives. The Monroe Doctrine, contrived by President Monroe in 1823, is a lucid example of America’s pursuit of geopolitical interests in the Pan-American region. The Doctrine was an audacious declaration to the powerful European nations to abstain from the region. It followed the spirit of â€Å"Manifest Destiny†, the rousing conviction that Americans had the right to seize the territory surrounding them. According to Coerver and Hall, the essential principle that this Doctrine was based upon was the â€Å"conviction that the United States was destined to expand†(13). The authors proceed to remark of the State Department’s concern that Spain’s loss of its empire may yield to other European powers taking over various areas of Latin America, especially the prospect of Br... ...icy in the region. Through the analysis of the Monroe Doctrine, the Roosevelt Corollary, the importance of the Panama Canal, and a host of other examples, one can perceive the great importance America imposes on its national security interests. Even to this day, geopolitical concerns dominate American foreign policy. This time, however, Latin America goes unobserved as the United States proceeds to pursue its new strategic interests in the Middle East. Works Cited 1. Coerver, David and Linda Hall. T a ngled Destinies . Albuquerque: U of New Mexico P, 1999. 2. LaRosa, Michael and Frank O. Mora eds. N e ighborly Adversaries: Readings in U.S. - Latin American Relations . Oxford: Rowman & Littlefield Publishers, Inc. 1999. 3. Brockett, Charles. â€Å"An Illusion of Omnipotence: U.S. Policy Toward Guatemala 1954- 1960.† Latin American Politics and Society, 2002.

Harnessing Solar Energy

Harnessing of Solar Energy: Photosynthesis versus Semiconductor Based Solar Cell Photosynthesis and semiconductor-based solar cells are both used to harness solar energy from the sun – photosynthesis for plants and semiconductor based solar cells for human beings. Photosynthesis consists of light reactions and dark reactions. It is a process in which carbon dioxide (CO2), water (H2O) and light energy are utilized to synthesize an energy-rich carbohydrate like glucose (C6H12O6) and to produce oxygen (O2) as a by-product.Simply put, photosynthesis is a process that transfers energy from the sun (solar energy) into chemical energy for plants and animals. Photosynthesis is a vital process among plants, algae and some bacteria that are able to create their own food directly from inorganic compounds using light energy so that they do not have to eat or rely on nutrients derived from other living organisms. A semiconductor-based solar cell is devised to convert light to electric curr ent.The solar cell directly converts the energy in light into electrical energy through the process of photovoltaics (a field of semiconductor technology involving the direct conversion of electromagnetic radiation as sunlight, into electricity). Solar cells do not use chemical reactions to produce electric power, and they have no moving parts. Most solar cells are designed for converting sunlight into electricity. In large arrays, which may contain many thousands of individual cells, they can function as central electric power stations analogous to nuclear, coal-, or oil-fired power plants.The conversion of sunlight into electrical energy in a solar cell involves three major processes: absorption of the sunlight in the semiconductor material; generation and separation of free positive and negative charges to different regions of the solar cell, creating a voltage in the solar cell; and transfer of these separated charges through electrical terminals to the outside application in th e form of electric current. Comparisons Photosynthesis and semiconductor-based solar cells both get their energy from the sun and convert it into a form that is needed either by plants or humans (Vieru, 2007). The first two steps of photosynthesis involve capturing photons released from the sun and using that energy to create a flow of electrons. From there, photosynthesis involves using that electrical energy to create chemical energy† (Stier, 2009). The products of photosynthesis are sugars to feed plants. Semiconductor-based solar cells also capture photons that use energy to create a flow of electrons which create electrical energy. A final similarity between photosynthesis and solar cell technology is that â€Å"a semi conductor has solar cells that trap energy from the sun and convert it into electricity.Plants have cells that trap energy from the sun and convert it into useful products† (Haile & O’Connell, 2005). Contrasts The first contrast is in the conv ersion of energy trapped by the sun – photosynthesis converts solar energy to chemical energy used by plants and semiconductor-based cells convert solar energy into electricity used by humans. The solar panels for semiconductors are manmade and photosynthesis comes from a natural process. Finally, photosynthesis has been around for billions of years making it the oldest technology on earth (Stier, 2009).Charles Fritts created the first solar panel in 1883 which means the semiconductor has been around for about 229 years – a mere zygote to photosynthesis. Thermodynamics Semiconductor-based solar cells and photosynthesis both use the laws of thermodynamics. Thermodynamics is the study of the conversion of energy between heat and other forms, mechanical in particular and it has three laws. The first law of thermodynamics says that energy is conserved, it is neither created nor destroyed but can change form. This is called energy conservation.The second law of thermodynami cs says that systems always tend to be in states of greater disorder. As disorder in the universe increases, the energy is transformed into less usable forms. The third law of thermodynamics is usually stated as a definition: the entropy of a perfect crystal of an element at the absolute zero of temperature is zero. Thermodynamics apply to photosynthesis by plants transforming sunlight energy into food – this is an example of the first law. During the process of photosynthesis plants also lose energy because they to not convert all of he energy trapped from the sun into food. Some of the energy is lost in the process – this demonstrates the second law of thermodynamics. Plants needing to trap energy from the sun constantly demonstrates the final law of thermodynamics because the cycle is repeated. In semiconductor-based solar cells energy from the sun is converted to electricity – this is the first law. Because energy is lost in the conversion, the second law of thermodynamics is applied here. Finally, the cells have to continually obtain energy from the sun which obeys the third law of thermodynamics (Heckert, 2007).Solar energy has been around for billions of years whereas semiconductor-based solar cells have only been around a little over 200 years. In writing this, I have discovered that solar energy is harnessed by both photosynthesis and semiconductor-based solar cells to convert energy into food and electricity to be used by plants and human beings. Both photosynthesis and semiconductor-based solar cells utilize all three laws of thermodynamics by converting energy, losing energy, and trapping energy constantly. This shows the many similarities and differences between photosynthesis and semiconductor-based solar cells.

Patient Profile Preferred By Doctors For Polypill...

Fig.1: Patient Profile preferred by doctors for Polypill prescription. Further analysis leads us to the top indication groups in secondary CV prevention where doctors would prefer polypill like CAD / T2DM /HTN: 23%, HTN with IHD: 17%, CAD/HTN/ Chronic Heart Failure (CHF): 15% (Fig.2) Results from our survey also showed that 90% Doctors believe that Polypill Improve Compliance and adherence to the treatment. Fig.2: Indications Preferred by doctors for Polypill in CVD management Patient Profile Indications for Polypill in CV Management Polypill usage in a cross section of Indian Physician Primary CV Prevention 6 % High Risk Primary Secondary CV prevention 67 % CAD / T2DM/HTN 23 % HTN with IHD 17 % CAD/HTN/CHF 15 % Discussion: This survey is the first to the authors’ knowledge to examine Awareness, Attitude and Usage of a Polypill approach among a cross section of Indian cardiologist and physicians. The findings can be summarized as follows : Based on risk/benefit ratio there is a high level of acceptance for prescribing a Polypill for primary and secondary prevention to high risk patients and a moderate level of acceptance for prescribing it to moderate risk patients, physicians would prefer Polypill instead of multiple drugs to improve adherence and compliance to therapy. However, Indian physicians currently have very high level agreement with the idea that multiple CVD risk factors need routine prescription of Polypill. The clinical type of Polypill approach