Question: Oppression is everywhere and exists in almost every form. How should believers respond to oppression when they have to face it?

Oppression, at its most basic form, is a transgression of boundaries and a violation of others’ rights. Killing an ant is oppressive, for nobody is authorized to take an animal’s right to life unjustly. If it is human who is being unjustly treated then it is definitely a form of oppression of a much higher magnitude. As for the oppression committed against a collective group of people, that is an incomparably greater and more horrible misdeed.

Irrespective of its exact nature, believers are seriously warned not to oppress others. Otherwise, it will appear on the Day of Judgment as a manifold darkness that will suffocate and distress the one who oppresses (Bukhari, Mazalim 9; Muslim, Birr 56). Each act of oppression and injustice – be it against animals, people, or even God – will appear before that person as a separate trouble in the Afterlife.

Oppression, according to some insightful scholars, is among one of the obstacles that can prevent a person from embracing faith. While it is an obstruction to having belief in God, it is similarly a significant reason that causes believers to drift out of the realm of faith.

Preventing oppression

Given that oppression is evil to this degree in regard to how other people are treated, it definitely needs to be prevented. According to Prophet Muhammad, peace be upon him, everyone should try to prevent oppression depending upon their capability, power, and position be it by direct intervention or via verbal objection. In the event that a person cannot resist oppression physically or verbally, it is at least necessary to protest the oppressor in one’s heart (Sahih al-Muslim, Iman 78; Tirmidhi, fitan 11; Abu Dawud, salat 239). Likewise, it is a famous old adage that “(the) one who remains silent before oppression is a mute devil.”

Preventing oppression on a smaller scale is within the capability of individuals, but there are some forms of oppression that can only be prevented by the state. In this contemporary world when justice and democracy have wide – though not perfect – prevalence such oppressions are committed at degrees big enough that even states are not able to tackle them. Preventing those oppressions and successions of atrocities, by which people are swept away in floods of blood, families are shattered, children are orphaned, and spouses are widowed, can only be possible through the hands of certain international establishments and organizations. In this respect, those who remain silent before oppression while they have the power to stop it—be they individuals, a state, or an international establishment—in a way have a share in that oppression by turning a blind eye to it and not taking the preventive action that they could have, and they will be treated accordingly on the Day of Judgment.

As it is very important to take a stance against oppression and to prevent it, determining the correct strategy to follow while not making any mistakes with the method is no less important. People must reckon well from the beginning how they can prevent unfairness, be aware of their capabilities, and also must not exacerbate problems while attempting to prevent oppression. They must not commit evil by thinking that they are doing something good.

Nothing good can come from oppression

It is a gross delusion to think that one can reach any positive goal via oppression and injustice. While it is not possible to obtain any favorable outcome with oppression, it is not possible to reclaim one’s violated rights via oppression either. If people try to move themselves or their societies in a new direction, or try to reclaim the rights that they lost by means of oppression, then this will give way to new acts of oppression, violations of rights, and a shattered system of justice. If these demands are for rights to be upheld and for justice to prevail, then strict adherence to a righteous course is needed from beginning to end. Just as the end should be lawful, so should be the means and ways to that end.

We do not know exactly to what degree we can prevent any oppression and injustice in our time. What matters most is being on the path to setting things right and correcting previous misdeeds. The duties that befall the wayfarers of the righteous path are that they must always be representatives of what is right and truthful, open one’s heart to everyone, and also not respond to oppression and injustice committed in the same wrong way. To put this in the words of the Poet Nabi:

“Do not trouble anyone with oppression
Even if they did oppress you, you do not be unjust to them
Do not arrive at God’s door with complaints
As for those who oppressed you, leave them to the Divine.”

Be like Rumi

In many instances, we quote, with a little bit of boastful considerations, the names of masters such as Jalaluddin Rumi, Yunus Emre, Ahmad Yasawi, or Haji Baktash Wali and bring their tolerance to attention. It is easy to make mention of Rumi, but it is difficult to be like him. At a time when you make mention of Rumi, are you really able to open your arms for all people, even for those who insulted you? When they come upon you, do you seek ways to settle issues in a peaceful manner? Are you able to make those who bear hostility against you share the same peaceful considerations after a while? This is how you become a Rumi in the real sense.

Historians mention the following anecdote about the tolerance of Rumi: One day, a rude bigot accosted him and criticized his statements such as, “one of my feet is in the center of Islam, while the other is among all nations of the world.” He accused Rumi of apostasy, misguiding Muslims, and proceeded to let out an invective against him. Without ever interrupting the man, the venerable master listened to him peacefully with God-granted self-restraint. On seeing that the man stopped talking and had no other words to say, he asked if he was done. When the man replied in the affirmative, Rumi spoke with a soft voice and said, “You are most welcome; my heart is open for you too.”

This is the very point at which words cease. In such a situation, all of the negative feelings within the latter melted away. The grudge and hatred suddenly started pouring down in the form of fireworks of love. While it is possible to treat people with showers of light, why should we shower them with meteors instead?

If you are focused on representing the spirit of Rumi, even if those who show hostility towards you commit oppression and injustice against you for one, two, three, or four times, they will give up such acts after some time on account of not having the same kind of response from you. Now, while there is a way to settle issues with mildness and agreement, why should we engage in other behavior that will only spur ill-feelings and hatred?

One thing that needs to be kept in mind is that we can give up on our personal rights and forgive others for their unfair treatment of us. However, we do not have the authority to forgive on behalf of others when there is an offense against values like faith or country. When such an offense happens, we should make plausible explanations to offenders to show them what they are doing is wrong. If they still insist, we deny their claims with denouncements. If they still persist, then we sue them and claim compensation.

We must always act carefully to remain within the confines of laws and ethics, and we must never make concessions on our fairness when responding in these ways. It is paramount that we must always act humanely but assertively. Even while making certain clarifications, corrections, and denouncements, we always try to give positive messages to the other side and never make concessions from our own character. We voice what we are to say not with whisperings of Satan, but with the voice and breath of the Archangel Gabriel. Oppression and assaults only indicate the character of the offender. This situation should not avert people attached to faith and universal human values to act as becomes their own character.

Is it worth it?

This passing worldly life is neither worth committing oppression against others nor responding to their oppression in the same way. After all, each of us is a traveler in this world. After staying in this guesthouse that we call life, we will pass to the Afterlife in order to be brought to account for what we did here. Is it worth it to promote fighting? Is it worth it at all to cause disunity and dissension? Is it worth it at all to commit oppression and injustice?

In an anonymous saying, the simple and transient nature of the world is expressed as follows:

Behold with the eyes of wisdom, this world is but a guesthouse;
Not a single person remains settled, what a strange abode it is.
The share of a king and subject alike, is nothing but a plain shroud.
As for those who fall for it, what else can they be called but mad?

Humankind has oftentimes made use of oppression and hatred in order to solve the problems that we collectively faced. If only we could make use of love and tolerance from now on! If only we were able to open our hearts to everyone so that those who enter therein would never have worries of remaining without a seat. If only we would treat everyone with a deep feeling of respect and reverence, and if only we could read into other’s feelings, their cultural backgrounds, and treat everyone with a serious feeling of empathy! For whatever style of treatment we expect to receive from others, they similarly expect the same from us. If we expect respect, we must show respect. If we expect observance of our rights, we must observe everybody’s rights.

It is necessary to know that the problems in our time have taken a complicated form to such an extent that they cannot be tackled by those with narrow minds and dull thoughts. There is not much that those with radical thoughts, who act out of bigotry in order to pursue arrogant purposes, can do for the sake of conquering people’s hearts and bringing peace to humanity. Particularly with this harsh attitude of theirs, they can never evoke in hearts any love towards their own values. They cannot let others love the Pride of Humanity, peace and blessings be upon him, because they are too captivated by their own worldly, illicit desires.

Therefore, for the sake of solving the problems of humanity, there is a need for people with immense conscience, rich hearts, and profound thought. Just as Rumi brought people together anew with the plausible cures he came up with some 7-8 centuries ago, in the contemporary world when people are so detached from one another, when people cannot agree on anything, and relations are built upon conflict and hostility, the duty that falls to those with faithful hearts is to revive the spirit of Rumi once again. As far as this cannot be done, it will not be possible to put a stop to oppression and hostilities in different parts of the world. This is particularly the case if we consider to what degree world peace is under threat by ambitious tyrants and horrible weapons prepared with vengeful intentions. It will then be best understood how great the responsibility is of the altruistic souls who have dedicated their lives to love and tolerance.

Among tropical fruits, bananas are probably the most popular, and with good reason. They are delicious and nutritious, and can be consumed by everyone, from babies to seniors.

The banana plant belongs to the Musa genus. The varieties preferred for cultivation are two hybrid species, Musa accuminata and Musa balbisiana. These types are mostly produced in Southeast Asia, Africa, and South and North America.

There are many varieties of banana. Short Cavendish, mid-sized Grand Nines, and longer Chiquita are some of those. The main harvesting occurs in September and October, but bananas can be produced year round in greenhouses.

Bananas are not reproduced by seeds. They reproduce through tissue culture – pieces of tubers or underground shoots. Underground perennial tubers spread horizontally and grow roots. Once the leaves and sheaths inside the annual aerial pseudostem reach a certain number, a flower bud is developed. The flower stalk, rising among the leaf bundles that are in the center of the pseudostem, carries the purple colored flowers that will become fruit.

When these flowers bloom, sounds can be heard. These sounds occur during the tearing of stem when the flowers force away from the crust to form the banana clusters; this is also known as inflorescence. While the buds are quickly developing, the purple leaves open and flowers become visible. Once the flower inflorescence emerges completely, it bends towards the ground. Fruits then form. Since the banana is a parthenocarpic plant, its fruit is generated without pollination from female flowers, like seedless grapes. The approximate time required for flowers to give fruit and become ripe is three months (1).    

Bananas are rich in nutrients. There is 1.1 gr. of protein, only 0.2 gr. of fat, 22 gr. of carbohydrates (fructose, glucose, sucrose and starch, cellulose, pectin), along with minerals like potassium, calcium, iron, phosphate, copper, zinc, and magnesium in 100 grams of a banana. It also contains fruit acids, along with vitamins A, B1, B2, B6, B9, C, D, E and P vitamins. Before bananas ripen, when they are still green, they contain approximately 1% sugar and 20% starch. As they ripen, the sugar content rises to 20% and the starch level drops to 1%.  

Bananas are harvested green and unripe and are matured in a closed environment. Unripe bananas can be stored for up to 15 days at 5-10 degree Celsius and 80-90% relative humidity. Maturation is enabled via ethylene gas, in storage rooms or during shipment. The shell becomes completely yellow, with brown spots, when the banana ripens. These spots indicate the sufficient conversion of starches into sugars. It is recommended to consume the ripe fruit as soon as possible.

In the past, the transportation of mature fruits to remote regions was a major problem, but this is not the case today. It is because methylcyclopropene (MCP) is used to delay the ripening of the fruit. When MCP is used, it binds to ethylene receptors, and slows down maturation (2). The proper storage temperature is 13-15 degrees (Celsius), so they get darker in the fridge faster. Therefore, it is advised to store them in a suitable place in a paper bag (3).

Even though they are usually eaten raw, as a fruit, some banana types are consumed after cooking. They can also be utilized as chips, baby food, puree, flour, or juice. In some places, banana flowers are used in salads and as decoration. Furthermore, bananas are employed in facial and skin care products. The leaves and stalks of the banana plant may also be used in the construction of roofs, and the fibers can be used as ropes, upholsteries, or even hats.  

According to the statistics of the Food and Agriculture Organization of the United Nations (FAO), the annual production was 55-60 million tons in 1995, whereas it is 90-100 million tons today. 25% of the production occurs in India, and the majority of the rest takes place in the Philippines, China, Brazil, and Ecuador. Even though they are grown in various parts of the world and traded widely, bananas are mostly imported by developed countries.

Benefits of the banana

Bananas can help prevent many diseases or provide complementary aid to different therapies. When a banana is blended with milk, it can serve as an ideal starter food for babies, and can also reduce wear and tear on the body, delaying aging.

Bananas have been shown to help after stomach or intestinal bleeding, and in patients with ulcers or various laryngeal problems. They can help prevent acid reflux. The sodium and potassium contained in bananas are effective for restoring heart beat rhythms and the body’s osmotic balance. Since bananas are rich in iron, they’re beneficial for anemia. Due to a high amount of serotonin, bananas can actually make people happier, improving our decision making and concentration. Because they can actually make us less depressed, bananas are a recommended snack (5).

Bananas help support the development of children’s skeletal structures, and can ease the pain of menstrual cramps. Aside from being an energy source, bananas help the nervous system function properly, maintaining the acid-base balance of bodily fluids and strengthening the immune system. Because of high magnesium and potassium, they help us sleep better – thus making a banana the perfect midnight snack!

Carbohydrates can cause instant blood sugar spikes, but they are also the most important energy source of the brain, central nervous system, and muscles. When blood sugar rises, it is stored as sugar or fat with the help of insulin secreted by the pancreas. This can cause obesity, or even diabetes, if a person ingests too many carbohydrates. Therefore, one must consume high sugar foods like bananas at the right time, and in the right amount.

Beta-carotene, one of the precursors of vitamin A, happens to be abundant in bananas. Beta-carotene helps with the neutralization of free radicals, supports the immune system, prevents cardio-vascular disease, and is protective against cancer. It’s more beneficial when taken together with vitamin E and C, which are also found in bananas.

The good news keeps coming! Due to a high amount of fiber, bananas are great for dieting and can also prevent colon and bowel cancers. Bananas can also help to regulate bowel functions.

Genetically modified banana plants are also employed for the synthesis of vaccine proteins used against Hepatitis, rabies, dysentery, cholera and other intestinal infections (7).

As you can see, the banana has been imbued with an extraordinary amount of positive properties. It’s not difficult to look at bananas as an amazing blessing bestowed upon humanity.

There are two main points to this question – this matter has aspects that relate both to the people of guidance who are attached to God, and to those who are not.

It is the duty of the people of guidance to communicate to other people the truth as they believe, the truth they have found and had a taste of; the truth they are satisfied with or a view with which they mature with, and to guide them to peace. First and foremost, this is a debt of conscience we owe to humankind. A person who knows these truths, the content of which has been bestowed to our consciences as a divine favor, should communicate them to those who do not know and open for them the doors leading to God.

Now, let’s have look at how God has commanded about this matter: “The believers, both men and women, they are guardians, confidants and helpers of one another. They enjoin and promote what is right and good and forbid and try to prevent the evil” (Qur’an 9:71). Another verse reads: “O you who believe! There must be among you a community calling to good, and enjoining and promoting what is right and good and forbidding and trying to prevent evil (in appropriate ways). They are those who are the prosperous.” (3:104). God has always referred to those who promote what is right and good as an honorable community: “You are the best community ever brought forth for (the good of) humankind, enjoining and promoting what is right and good forbidding and trying to prevent the evil, and (this you do because) you believe in God” (Qur’an 3:110).

These divine lights considerably clarify this obligation towards humanity. This matter is clarified by many other verses and hadiths and it is so open and clear that it does not require any further interpretation or explanation. Therefore, we can gather from these verses that we are responsible for communicating the divine truths. This is such a compelling responsibility that if there was no one left on earth one day in future, then we will entertain the possibility that there might be people living in a colony near Sirius or some distant planet around some unknown star in the Hercules constellation and somewhere in the Milky Galaxy, and with an urge that is unique to human species to reach out to them, we will build colonies and cities as interim stations on our route toward them, and we will communicate our heart-felt inspirations to the people there (if any). We will intermingle and sympathize with them and we will show them the roads that will lead to God. We will say, “Say, ‘There is no god but God,’ and be saved and be prosperous,” as the Prophet, peace and blessings be upon him, put, and this will always be our main motto. This is our duty. On the other hand, their duty is to lend an ear to this call of ours that invites them to peace and to search for the straight path wherever they are and everywhere they go.

If we do not fulfill our duty, we will fail to comply with our obligation towards God. Then, Almighty God will ask questioningly: “You knew the truth, but you failed to communicate to other people? You knew God, but you did not introduce Him to other people? You could see the straight path, but why didn’t you show it to other people? You were aware of the light, but why didn’t you turn other people to look toward that direction?”

In the light of divine revelations, I can say that on that day, Almighty God will say to them: “Although you satisfied all of your animal drives to the full, why didn’t you search for the way which would provide you with full gratification? Even during your most troubled and distressed times, you did not think for an instant to experiment this way? In other words, you have resorted to all sorts of recipes for your worldly welfare, but why didn’t you consider making the truth which you somewhat heard about even for once?”

In the final analysis, Almighty God will hold every individual against his or her own sins. Since we are responsible only for communicating the truth to them, we will be questioned only for our faults in fulfilling this duty of ours. On the other hand, they will be questioned for failing to search for truth or lend an ear in a sincere manner to the truth, if they have already heard about it. May God save us from falling tumbling down by failing to enjoin and promote what is right and good, and forbid and try to prevent the evil while having capability to do so!

Less well known is that research is also continuing into the scent of repellents to deter pests like insects and ticks. Various plants are known for the effects of their aroma, and are in widespread use for protection, especially in very hot and humid climates where there are a great number of arthropods; for instance, it is known that mosquitoes will not approach a house that has basil plants on the windowsill.

Another plant which is well known and used commonly for its scent is “patchouli” (pogostemon cablin), the scented essential oil of which is obtained by steaming the plant and collecting the oil which emerges. The plant is a member of the mint family, and its actual origin is India, where its scent can be found even in the famous Indian ink. Patchouli leaves used to be placed between carpets and rugs made in Iran and Turkey to protect them from any harmful pests or insects before they were sent to Europe. During the Victorian period carpets, shawls and rugs exported from India were also sprinkled with the fragrance of patchouli to protect them from moth, In fact any carpets, rugs or shawls that did not have the scent of patchouli were not favored because they were believed to have been manufactured in Europe. The fragrance of the plant, which is longer lasting than most other scents, is believed by the Chinese, Japanese and Arabs to prevent the spread of infectious diseases and also used frequently in perfumes and soaps. Widely used in Europe in the eighteen hundreds, patchouli became the most popular fragrance of the generation in America in the sixties.

The research into patchouli has been limited so far and scientific observations are insufficient; nevertheless, the chemical composition of the various scents found in the oil of this plant have been identified, and the long human experiences of using this plant and its fragrance may hold great significance for scientific research in the future.

The plant contains patchouli alcohol, pogostone, friedelin, epifriedelinol, pachypodol, retusin, oleanolic asid, beta-sitosterol and daucosterol, most of which prevent nausea. It has also been found to contain alpha-bulnesene, which prevents the clotting of blood. In addition, according to an article in the 2008 February edition of the Phytotherapy research journal, since the oil obtained from patchouli essence is an effective fly killer, the oil could also be an effective as a component of insect repellents and might even be an effective arthropod and tick repellent.

Looking at these studies we clearly see other ways in which we could benefit from this substance; for instance, by adding a few drops to water we could use it in household cleaning and therefore get rid of unwanted odors at the same time as preventing insects in the home without the use of carcinogenic chemicals. The oil is also known to be used to prevent fungus, to reduce perspiration and eliminate unwanted body odors and for dietary purposes, due to its effectiveness in reducing the appetite.

Moreover, patchouli has also long been a fragrance very much sought and used as a form of treatment for its soothing qualities and positive effect on spiritual health. Martin Henglein, who was one of the founders of aromatherapy and developer of the theory of the curative aspect of the fragrances of plants, recognizes geranium, rosemary, bergamot, and patchouli as the four primary aromas, and he emphasizes that these four fragrances perform various functions. Geranium can prevent addictions from progressing and even assist people in abandoning addictions and bad habits. For instance, the role geranium plays in giving up smoking is indisputable: when the desire to smoke increases and becomes unbearable the aroma of geranium temporarily eliminates the desire to smoke. According to Henglein, rosemary improves memory while bergamot increases activity in the brain and the ability to understand; patchouli activates the mechanism which motivates a person’s energy.

Robert Tisserand, owner of a treatment center in England, believes that certain fragrances can also cure psychological illnesses, Tisserand says that these aromas have a positive effect on the signal molecules (neurotransmitters) that provide communication with the nerve cells and can help to cure psychological problems. Fragrances encourage the body to release endorphin, a substance which resembles morphine (a pain reliever) and this is why rose oil, jasmine, sage, cananga (ylang ylang), patchouli, and grapefruit are recommended for depression, to increase confidence, and to help with abnormalities of sexual function. If patchouli is used in excess, it allegedly may cause a sedative effect or may reduce sleep. Otherwise, it is claimed to have a balancing effect on the body’s energy and psychological condition, inspire a sense of calmness, eliminate laziness, support treatment of addictions, and relieve feelings of fear and depression.

Everyone knows that charming fragrances enhance positive thought and feelings, and we also know the negative aspects of bad odors. It is reported that the Prophet Muhammad, peace be upon him, said, “I have been made to love perfume,” drawing attention to the importance of pleasant fragrances and reminding us that Jacob received the glad tidings that his son Joseph was still alive because of the scent of his shirt.

References

• Guan L, Quan LH, Xu LZ, Cong PZ. (1994): Chemical constituents of Pogostemon cablin (Blanco) Benth. Zhongguo Zhong Yao Za Zhi. 1994 Jun;19(6):355–6, 383.
• Yang Y, Kinoshita K, Koyama K, Takahashi K, Tai T, Nunoura Y, Watanabe K.(1999): Anti-emetic principles of Pogostemon cablin (Blanco) Benth. Phytomedicine. 1999 May, 6 (2): 89–93.
• Luo J, Guo X, Feng Y. (2002): Constituents analysis on volatile oil of Pogostemon cablin from different collection time cultivated in Hainan. Zhong Yao Cai. 2002 Jan. 25 (1): 21–3
• Hsu HC, Yang WC, Tsai WJ, Chen CC, Huang HY, Tsai YC. (2006): Alpha-bulnesene, a novel PAF receptor antagonist isolated from Pogostemon cablin. Biochem Biophem Biophys Res Commun. 2006 Jul 7;345(3):1033–8.
• Tsai YC, Hsu HC, Yang WC, Tsai WJ, Chen CC, Watanabe T. (2007): Alpha-bulnesene, a PAF inhibitor isolated from the essential oil of Pogostemon cablin. Fitoterapia. 2007 Jan. 78 (1):7–11.
• Pavela R. (2008): Insecticidal properties of several essential oils on the house fly (Musca domestica L.). Phytother Res. 2008 Feb;22(2):274–8.
• Jantan, I. and Zaridah M. Z.(1999): Development of Environment-Friendly Insect Repellents From The Leaf Oils of Selected Malaysian Plants. ASEAN Review of Biodiversity and Environmental Conservation (ARBEC) November–December 1999, p.1–7.

The muscle cells are responsible for the strength and tone of the vessels. Today, we know that the role of the endothelial layer goes beyond a simple physical barrier. In addition, there are twenty-five different substances secreted by the endothelial cells that play a role in blood clotting, cell proliferation, the regulation of vessel permeability, and the functioning of the immune system. The endothelial cells are 10-15 &μm wide and 20-25 μm long. They are located in the inner vessel wall in a single-cell layer. The total endothelial area in the body of an adult is around 5000-6000 m², and it weighs around 2.5 kg. Endothelial cells during inflammation Capillaries consist of an endothelial structure; they can only be seen under a microscope, but their total length is nearly 96,000 km. The blood brought by the arteries is conveyed to the vein through capillaries. At this stage, the gas, liquids, and nutrients are brought out through the vessels and the cells and tissues around are supplied with oxygen and nutrients. In return, the liquids that they discharge and other waste matter are conveyed to the vein through capillaries. This matter-exchange, which occurs both inside and outside of the capillaries, is regulated thanks to the permeability of the endothelial cell layer and the pressure balance of the capillary system. During cardiac failure and inflammation, liquid release is increased due to a pressure imbalance and the liquid retrieval is not sufficient to make up for the amount lost. This results in swelling in the area in question. Here, we need to underline that inflammation, which appears with symptoms such as edema, redness, fever, and pain, is not a harmful process. On the contrary, it is a miraculous defensive mechanism granted to our body; inflammation protects the body against serious damage. For instance, the inflammation that forms around a bee sting prevents the venom from spreading throughout the body. The endothelial cells are given an important role in the inflammation as well. The chemical molecules secreted by the endothelial cells in the inflamed spot cause the vessels to react by enlarging and thus perfusion is increased. Later, the endothelial layer becomes ready for leukocytes to settle; these are used in neutralizing the substance that caused the inflammation in the first place.

Balancing blood pressure

The layer of smooth muscle cells is stimulated with chemicals secreted by the endothelial cells and the tone of the vessels are controlled through the constriction and relaxation of the vessels. Therefore, an important duty in the regulation of blood pressure is given to these cells. During aninfection, bacteria circulate in the blood stream and the blood pressure falls extremely low. Tissue nutrition is upset (septic shock) and an excess of muscle-relaxing substance is released by the endothelial structure. Veins and arteries become too relaxed and there is a considerable drop in blood pressure (hypotension). On the other hand, with problems like atherosclerosis, the endothelial cells cannot fulfill their duty and due to a deficiency in nitrogen oxide, they become immune to the stimulus to relax the muscles. The resulting problem in this situation is hypertension.

Endothelial cells prevent hemorrhage

In order for a hemorrhage to stop the vessels that are bleeding need to narrow down. This is very important in the first stages of blood loss, particularly when there is a problem with blood clotting. When a hemorrhage begins, the endothelial cells are ordered to excrete a substance called endothelin. This starts the narrowing down of the bleeding vessels. Endothelin is not excreted in normal vessels. When the umbilical cord of a newborn is cut, it prevents the baby from losing blood.

Endothelial cells in blood clotting

The duty of endothelial cells can prevent or facilitate blood clotting, depending on the situation. First of all, they prevent the blood cells from adhering to the vessel walls and prevent clotting inside the vessels. Imagine water flowing through a pipe. The speed of the flow is greater in the center and lower at the periphery. Therefore, in the long run, some residue forms inside the pipe. In the veins and arteries, the flow of blood near the walls is also slower. To prevent the formation of any residue, both the endothelial cells and the blood cells are created with negative loaded surfaces and the blood cells are pushed towards the center. In addition, a substance called prostocyclin (PGI2) is excreted and the thrombocytes change their structure. As a result, residue formation and clotting is prevented along the vessel walls. In a case of any long term damage to the endothelium (e.g. due to smoking, diabetes, or hypertension), the relevant protection mechanism fails, and clotting inside the vessels results in thrombosis. Some serious cases can even necessitate the amputation of a limb. The endothelial cells can also facilitate clotting when necessary. In case of bleeding due to a wound, they function contrarily and help the blood to clot to prevent blood loss.

Endothelial cells in the bone marrow, the liver, and spleen

As a divine blessing, the endothelial cells form a looser layer in these organs and vessel permeability is increased. Thanks to this increase, matter Exchange with blood is easily realized; blood reaches these organs, which are responsible for the constant control of the contents of the blood, easily.

Endothelial cells in the brain and eyes

The endothelial cells in organs like the brain and eyes are very closely integrated forming a barrier between the blood and the organs. This is to such an extent that the major nutrients of the brain, like glucose and oxygen, pass without any obstacles, but several chemicals, including medication, are blocked by the selective-permeability of this protective mechanism. Research has proven that various substances injected into the bloodstream reach almost all the tissues except for the brain. Thanks to the efficient protective mechanism that has been given to these minute cells, the brain is saved from a great deal of negative effects. Even a single cell is not left to chance and nothing happens randomly. As can be seen throughoutthe universe, opposites are made to work hand in hand in the human body as well in a splendid harmony for the continuation of life.

References

• Vinay Kumar, Abul K. Abbas, Nelson Fausto, Richard Mitchell, Robbins Basic Pathology, W.B. Saunders; 8th edition, 2007. Hall, John E., Arthur C. Guyton, Textbook of Medical Physiology,

The second leading cause of death in the United States, after heart diseases, is cancer, claiming around half a million lives every year.(1) People today are concerned more than ever about cancer and its terrible consequences. However, in the light of recent scientific findings, a very different picture can be seen: In an environment with increasing carcinogens, it is actually surprising to find most populations are cancer-free. This is because our bodies are equipped with systems to prevent cancer formation.

Cancer research over the last two decades has shown that cancer is a disease of the genome.(2) Changes in the DNA, called mutations, disrupt the regular cellular networks that control a state of delicate balance. People are continuously exposed to varying amounts of chemicals that have been shown to cause mutations in the genome which may lead to cancer formation. Exposure to harmful chemicals can occur due to being in an environment where these agents are present in the food, air or water, and also due to our own metabolism which may produce these chemicals. It has been estimated that exposure to environmental chemical carcinogens may contribute significantly to the formation of the majority of human cancers.(3)

Even though some of the mutations caused by these agents hit cancer-critical genes, cancer does not immediately develop. Furthermore, cancer is mostly seen in old age, when many mutations have accumulated in the genome. The reason why we are protected from developing cancer, even though our DNA is under numerous types of attacks everyday, is that our cells are equipped with several lines of defense against cancer formation. These built-in defenses include DNA damage repair systems, external and internal controls of cell division rate, and the programmed death of cells. All of these defenses have been given to our cells in order to protect us from getting cancer. If we were not to have these defenses, cancer would be a daily occurrence for every one.

It is possible to say that a cell’s first defense against cancer is similar to the regular maintenance of a car. One has to replace the brake pads, change the oil, etc., so that the aging of the parts will not cause failure that may lead to an accident. Similarly, chemical carcinogens from environmental pollution, ultraviolet rays from the sun, radiation from various sources, etc. all cause multiple types of damage in the DNA molecule. Therefore, our cells and genome need maintenance as well. This function is carried out by groups of proteins called DNA repair complexes. DNA repair mechanisms have been designed to correct the DNA damage before it can lead to inheritable mutations.(4)

If the DNA damage repair systems are intact, most of the damages to the genome are dealt with before they can cause problems. We observe the extent of attacks that can damage the DNA on our genome in many types of cancer where the DNA repair mechanisms are known to have been inactivated. In these cancer cells, mutations accumulate at a very fast rate, leading to more aberrant behavior. Also, individuals with defective DNA repair systems are more susceptible to developing various types of cancer.(4,5) Therefore, the first line of defense given to our cells against cancer is the ability to check and correct the integrity of our genome.

Every cell type in our body has been designed to proliferate at a certain rate that is suitable for the function of those cells. For example, neurons or muscle cells almost never divide after reaching adulthood, whereas the epithelial cells lining the interior of the intestines or under the skin divide at a fast rate continuously throughout our lives. The rate of division of a cell is mainly controlled by extra-cellular cues, i.e. a normal cell doesn’t grow or divide unless it receives growth and proliferation signals from neighboring cells.

There is a safe rate at which a cell must divide – just as a car needs to be driven at a safe speed. The requirement of cells for external stimuli in order to grow and divide is like the car’s need for someone to step on the gas pedal in order to accelerate. Normal cells cannot grow without control as neighboring cells produce growth signals when they are necessary and stop producing them in a regulated manner. A good example of the control of cell proliferation rate is seen in the wound healing process. When there is a cut in the skin, the cells adjacent to the wound are stimulated to divide rapidly by signals given from the injured cells; they divide and close the wound as soon as possible. However, when there are no wounds, there is no signal to divide and the skin cells only divide at a very slow rate, just enough to replace dying cells; this is a much slower process than wound healing. Cancer cells, on the other hand, are known to produce their own growth signals and proliferate abnormally fast and in an uncontrolled manner.(6) Therefore, the environmental control of cell division is an important barrier against cancer formation.

Cancer cells cannot divide uncontrollably unless they are independent of the external stimuli to divide. However, cancer cells can produce their own growth and proliferation signals, so they are free from external constraints. But even then, all is not yet lost. This situation of uncontrolled and rapid cellular proliferation is like a car in which the accelerator has become jammed– the car accelerates continuously and an accident is impending. In this situation the way to prevent too much speed is to step on the brake of the car. Similarly, in a cell, there are a set of genes called tumor-suppressor genes, which are responsible for stopping cell division upon excessive growth stimuli.(7) These genes act like brakes in cell division and prevent further progression into a malignant state. In many cancers,(8) it has been shown that these genes have been inactivated. If the brakes of the car are functional, you can safely bring your car to a stop and fix the problem that caused the accelerator to jam. Similarly, if a cell starts to divide too rapidly, it can stop dividing and repair the damage that caused the uncontrolled growth. Therefore, tumor suppressor genes represent a third line of defense.

If all the previous safety valves fail, there is one more defense to cancer. A situation in which a cell with harmful mutations promotes its own proliferation and cannot abort the division process is similar to one where the accelerator of the car is jammed and the brakes don’t work. In this case, in order to prevent greater damage, one can choose to hit a wall or a tree to stop the car– this will total the car, but will prevent further damage to others. Similarly, if a cell begins to grow uncontrollably and can’t slow down its rate of division, a process called apoptosis, or programmed cell death is initiated. In apoptosis, the cellular DNA and cellular compartments, like lysozomes, Endoplasmic Reticulum, and Golgi are degraded, and the cell shrinks in size. In the end, the cell dies and is absorbed by neighboring normal tissue. Therefore, the programmed death of an aberrantly behaving cell is another way that the body is protected from cancer. As expected, in cancer cells defects in this last line of defense are observed as well.(9)

These four mechanisms, i.e. DNA repair, external/ internal cell division suppression, and programmed cell death, are only the ones that we are aware of at this time. In addition to these, there are multiple levels of other redundant safety checks. All these safety features work without our knowledge or will. Findings from cancer research show that the design of cells was carried out so intelligently that even the carcinogenic environment which we produce today was accounted for within the genes of the very first human being.

Notes

1. Cancer Statistics 2006. 2006, American Cancer Society.

2. Vogelstein, B. and K.W. Kinzler, “The multistep nature of cancer.” Trends Genet, 1993. 9(4): p. 138-41.

3. Wogan, G.N., et al., “Environmental and chemical carcinogenesis.” Semin Cancer Biol, 2004. 14(6): p. 473-86.

4. Dixon, K. and E. Kopras, “Genetic alterations and DNA repair in human carcinogenesis.” Semin Cancer Biol, 2004. 14(6): p. 441-8.

5. Jiricny, J., “The multifaceted mismatch-repair system.” Nat Rev Mol Cell Biol, 2006. 7(5): p. 335-46.

6. Brattain, M.G., et al., “Growth factor balance and tumor progression.” Curr Opin Oncol, 1994. 6(1): p. 77-81.

7. Hanahan, D. and R.A. Weinberg, “The hallmarks of cancer.” Cell, 2000. 100(1): p. 57-70.

8. Coleman, W.B. and G.J. Tsongalis, “Molecular mechanisms of human carcinogenesis.” Exs, 2006(96): p. 321-49.

9. Dlamini, Z., Z. Mbita, and T. Ledwaba, “Can targeting apoptosis resolve the cancer saga?” Future Oncol, 2005. 1(3): p. 339-49.