Glycolic Acid In Unripe Grapes

发表于 2012 年 5 月 11 日由 21food

Glycolic acid (alpha-hydroxyacetic acid) has the chemical structure HO-CH2-COOH. It is a chemical compound from the alpha hydroxy acid group found in some foods and is commonly used in skin care. High concentrations of glycolic acid can make skin look sunburned, but generally skin care products with the chemical can help get rid of wrinkles and prevent acne.

Properties
Glycolic acid is the simplest of the alpha-hydroxy acids. It consists of odorless white, hygroscopic crystals. Because of its small molecular weight and size it affords strong skin penetration. Alpha-hydroxy acids loosen glue-like substances that hold surface skin cells together. Because of this, treatment softens the skin.

Sources
Sources include fruits and vegetables high in sugar content, including green (unripe) grapes. Although glycolic acid can be produced from unripe grapes, fermented sugar cane juice is a more common source. Additional sources include barley and wheat leaves, cantaloupe, sugar beets and pineapple. Chemical methods of production are being used by some manufacturers such as DuPont.

Sugarcane
Sugarcane is frequently referenced in descriptions and definitions of glycolic acid. Used in moderate levels, glycolic acid found in sugarcane can work as an exfoliant and help get rid of dead skin cells on your face. Many skin experts used it found in sugarcane for facial peels.

Unripe grapes
Unripe grapes also are high in glycolic acid. An unripe grape is what you commonly call green grapes. Other fruits that glycolic acid can be found in are pineapple and cantaloupe. Although unripe grapes and sugar beets can be used in the chemical production of glycolic acid, the most common natural source is sugarcane.

Chemical Preparation
One patented chemical preparation of particularly pure glycolic acid involves the saponification of chloroacetic acid(C2H3ClO2, CAS No. 79-11-8) with an excess of alkali metal hydroxide, later followed by electrodialysis. It reduces wrinkles and improves other skin conditions.

Considerations
The Food and Drug Administration offers “guidance for industry” concerning increased sunburn risks for people using glycolic acid for cosmetic purposes.It metabolizes to form oxalic acid, hence ingestion is hazardous; however, in cases of ingestion, vomiting should not be induced.

Beta Lactam Antibiotics Description

发表于 2012 年 5 月 11 日由 21food

Beta lactam antibiotics are antibiotic drugs with a beta lactam ring in their molecular structure. They are among the most commonly prescribed drugs, grouped together based upon a shared structural feature, the beta-lactam ring. Doctors widely prescribe these drugs for patients with a range of infections. Bacteria can develop resistance to them, usually by creating beta lactamase, an enzyme that will break down the beta lactam so it can no longer harm the bacterial cell.

Drugs in this family work by interrupting the process of synthesizing a cell wall by binding to enzymes the bacterial cell uses in this process. The breakdown of the cell wall kills the organism and makes it impossible to reproduce, bringing a bacterial infection to a halt. Beta lactam antibiotics will not be effective if the cell is producing beta lactamase, as it breaks down the beta lactam before it has an opportunity to attack the cell wall. A doctor may prescribe the drug with a beta lactamase inhibitor to address this problem.

Beta-lactams inhibit not just a single enzyme involved in cell wall synthesis, but a family of related enzymes (four to eight in different bacteria), each involved in different aspects of cell wall synthesis. These enzymes can be detected by their covalent binding of radioactively-labeled penicillin (or other beta-lactams) and hence have been called penicillin binding proteins (PBPs).

Since this category of antibiotics is so broad, it is important to subdivide these drugs into functional drug groups to facilitate understanding and prescribing practices. It is not necessary for clinicians to know every drug within each of these groups. The grouping of these agents can be based upon spectrum of activity, for choice of agents for an antibiotic formulary, for therapeutic use or for routine susceptibility testing.

Within each functional group, differences between antibiotics in pharmacokinetics, safety, duration of the clinical experience with their use, and cost allow reasonable choices to be made in selecting an individual drug as representative of that group. (S)-4-Benzyl-2-oxazolidinone(C10H11NO2, CAS No. 90719-32-7) is used in the enantioselective synthesis of beta-lactams.

One of the most famous classes of beta lactam antibiotics is the penicillins. Cephalosporins, monobactams, and carbapenems are also members of this family of antibiotics. These drugs have different structures. Some are derived from natural sources like molds, while others are purely synthetic. The development of beta lactam antibiotics was a significant advance in medicine, making it possible to address a variety of infections with aggressive antibiotics to kill the bacteria.

Meropenem For Bacterial Infections

发表于 2012 年 5 月 11 日由 21food

One type of antibiotic medication used to treat a variety of bacterial infections is known as meropenem. It is classified as a beta-lactam, which is a cyclic amide that has a molecular structure comprising three carbon atoms and one nitrogen atom. The medicine is also known by the brand names Carbonem, Merrem, Meronem, Neopenem and Zwipen. As a beta-lactam antibiotic, it belongs to a class of drugs called carbapenem, which are characterized by the possession of a broad spectrum of antibacterial activity.

Mechanism
The Meropenem medication works by suppressing bacterial wall synthesis. Notably, it is resistant to the degradation of enzymes such as beta-lactamase, and it is a great penetrator of body fluids and tissues. It is most commonly used to fight meningitis and pneumonia. These are inflammatory conditions that affect the covering membranes of the brain and spinal cord and the lung, respectively. This drug is also used for bacterial infections of the bone, skin, urinary tract and stomach.

Administration
Regarding legal status, meropenem is available as a prescription medicine in the United States and the United Kingdom. In the former, the drug was approved by the U.S. Food and Drug Administration (FDA) in 1996. The FDA places it in category B of its classification of pharmaceutical fetal risk. It is one of the FDA’s milder rankings, thus making it a relatively low-risk drug for pregnant patients.

Usage
Often, this drug is used to eliminate germs that have not responded to other treatments, and it is a broad spectrum compound, effective against several species of organisms. Generally, calculating a sufficient meropenem dose depends on multiple factors, including the type of infection and the age and weight of the individual taking the drug. There is a need to carefully determine a dose of this substance that will be large enough to effectively treat the disease, yet not so high that it will create an elevated risk of dangerous side effects, including seizures and severe diarrhea.

4-Nitrobenzyl alcohol(CAS:619-73-8 ) serves as an intermediate of meropenem. Medical conditions may also influence a common dose. Individuals with kidney damage, for example, may not eliminate this drug from their body as quickly as those with healthy kidneys.

Effects
Physicians should also be informed if the patient has suffered or is suffering from kidney or liver disease. People who take meropenem may experience some side effects. They include dry mouth, diarrhea, constipation, headache, indigestion, injection-site inflammation and stomach problems.

Capsaicin Medicinal Benefits

发表于 2012 年 5 月 11 日由 21food

Capsaicin(C18H27NO3) is the chemical compound that makes chili peppers taste hot. It is found naturally in red chili peppers, giving the vegetable its distinguishing, pungent, spicy-hot sting. The ingredient is the active chemical in certain medications like skin pain patches and topical anesthetic creams used for treating muscle pain, neuralgia and arthritis. It is a skin irritant to humans, and can cause a burning sensation if applied to the skin.

Capsaicin, or more commonly, ingredients containing high amounts, are widely used as flavorings in spicy cuisines. All members of the pepper family that are hot have high levels of this compound. Hot sauces such as hot salsa and Tabasco are high in the substance, and you can easily burn your mouth eating spicy foods if you are not careful.

Capsaicin is also making news in the diet and nutritional fields. Some studies show that a diet high in chilis or other capsaicin-laden foods can raise your base metabolism, the rate at which your body burns fat while at rest. There are also studies claiming it both lowers LDLs, or ‘bad cholesterols’, but raises HDLs, or ‘good cholesterols’ too.

The chemical works by interfering with nerve receptor transmissions from the spinal cord and throughout the body. Applied topically, capsaicin is absorbed through the skin and provides minor relief for such painful conditions as neuralgia, or nerve pain, from the herpes zoster virus and after surgery. It also works for sudden and severe bouts of cluster headaches, for canker sores from post-radiation cancer treatment, and as a steroid replacement for such skin conditions as psoriasis. The product is also used as a pain reliever for arthritis, although it usually takes several weeks of continual use before the arthritis sufferer receives any relief.

Uses of capsaicin for diseases such as diabetes and cancer remains in experimental form. Scientists have discovered that chemical compounds in this chemical may treat diabetes and nerve inflammation. Studies performed by the American Cancer Institute show that it injected into mice with prostate cancer reduced tumors in the cancer cells, causing the cells to self-implode. The benefits of capsaicin(CAS No. 404-86-4) for treating more serious, chronic and debilitating disease remains to be seen.

With all that going for it, consider yourself lucky if you like spicy cuisines, and help yourself to as much capsaicin-generated heat as your mouth can stand. However, some patients are allergic to it, and the medicine on the eyes or mucuous membranes of the body may react with extreme swelling, burning, itching and respiratory problems. While rare, overdoses can be lethal. Patients with high blood pressure or heart problems should defer to a medical professional before using it skin patches for pain. Overall, the benefits outweigh the risks for most pain sufferers.

The Limiting Reagent In Chemical Reactions

发表于 2012 年 5 月 11 日由 21food

You can write every chemical reaction as a chemical equation. The equation describes in short hand notation what happens when chemical species react with each other. Similarly, if he has a certain amount of a reactant, it may be useful to find out how much product he will be able to make with it. The limiting reactant, also called a limiting reagent, limits the amount of product that can be made in a reaction—once this reactant is consumed, the reaction will stop.

The production of a specific amount of product requires enough of all the reactants to meet the ratios specified by the equation. When one reactant is not present in sufficient amount for the other reactants to carry out the reaction, it is the limiting reagent.

Example
To help understand what a limiting reagent is, think about something that almost everyone can understand. Consider making peanut butter and jelly sandwiches for your family or friends. You know the things required to make sandwiches are bread, peanut butter and jelly. You need to make 10 sandwiches. In order to make one sandwich, you need two slices of bread, some peanut butter and some jelly. You only have one loaf of bread on hand and it contains 17 slices of bread. For the construction of 10 sandwiches, you will need 20 slices of bread to complete the task. You are limited in completing the task by the amount of bread you have, therefore, the limiting ingredient for the process of making the sandwiches is the bread. In chemical terms, the bread would be the limiting reagent.

Chemical Equation Units
The limiting reactant is the reactant that will run out first as a reaction progresses. When the limiting reactant is used up, the reaction will cease. Any chemical or substance has the potential to be a limiting reactant. In order to determine which reactant is the limiting one, the chemist will need to determine how much of each substance he has. He will also need to know what proportion of each reactant the reaction needs in order to continue the desired amount of time. The result yields the number of moles of the reagent. You must perform the conversion for each of the reactants in the equation. TBTU(CAS No. 125700-67-6), or we can call it Knorr’s reagent is a reactant like this.

Comparison
Before he can determine which reactant is the limiting reactant, a scientist needs to know how many moles of each substance he has. Compare the number of moles of each reagent you have against the ratio of moles needed for the reaction and select the reagent that has the least amount. Remember the example of making sandwiches. If the reaction requires 3 moles of reagent A, 2 moles of reagent B and 1 mole of reagent C than the ratios are 1/3 for A, 1/2 for B and 1 for C. Take the number of moles of each reagent you have and multiply by the ratio for that reagent. The reagent with the lowest value is the limiting reagent.

Sunitinib Malate For Cancer

发表于 2012 年 5 月 11 日由 21food

Sunitinib malate, often referred to simply as sunitinib, is a prescription medicine that is used for the treatment of various kinds of cancer. It also prevents new blood vessels from growing inside of the tumor.When the medicine is taken according to doctors’ recommendations, it usually inhibi0ts the spread of cancer and occasionally shrinks existing tumors. The drug can cause side effects or react adversely with other medications, and doctors perform extensive medical evaluations before and during the course of treatment to prevent potentially life-threatening complications.

RTK
RTKs are essential enzymes for healthy growth and functioning of many proteins found in body cells. They promote active, organized intracellular processes, including those involved with metabolism and replication. RTKs perform the same functions in some cancerous cells, however, aiding in the progression and spread of the cancer. Sunitinib molecules inhibit RTKs in cancerous cells from beginning their replication sequences. As an effect, the cells cannot efficiently multiply and afflict nearby healthy tissue.

Function
It works by hindering the function of receptor tyrosine kinases (RTKs) in cancerous cells, enzymes that play a significant role in the development and growth of tumors.RTKs are essential enzymes for healthy growth and functioning of many proteins found in body cells.

They promote active, organized intracellular processes, including those involved with metabolism and replication. RTKs perform the same functions in some cancerous cells, however, aiding in the progression and spread of the cancer. Sunitinib molecules inhibit RTKs in cancerous cells from beginning their replication sequences. As an effect, the cells cannot efficiently multiply and afflict nearby healthy tissue.

Effects
A handful of common side effects are possible with Sunitinib. These side effects are considered to be minor because they usually fade away rapidly. However, if you have any of these effects and find them to be troublesome, you need to inform your doctor. These side effects are irritation or pain of the mouth, diarrhea, constipation, lower appetite, taste changes, upset stomach, stomachache, fatigue, weakness, throwing up, nosebleed, discoloration of the skin or the hair, nausea, indigestion, headache, and thick, cracked, or dry skin. 5-Fluoro-2-oxindole(C8H6FNO, CAS No. 56341-41-4) is an intermediate of this drug.

Severe allergic reactions can also occur with Sunitinib. These types of allergic reactions are unlikely, but can happen, and also can be very harmful. As a result it is necessary to get emergency medical help for these reactions.This cancer treatment is not suitable or safe for everybody. Some people are advised against the use of Sunitinib, such as those that are allergic to any of the medication’s ingredients, those taking St. John’s wort, and those taking bevacizumab.

Glutamine In Human Body

发表于 2012 年 5 月 10 日由 21food

Scientifically speaking, glutamine is one of the 20 amino acids formed by the human body. As a protein, it is a building block of muscle. It is a nonessential amino acid, which means it is produced naturally in the body and can be put to use without being ingested. The body uses glutamine to improve mental function, control blood sugar levels and maintain muscle mass, among other applications.

Features
Glutamine is the most abundant building block of protein in the bloodstream. The body produces it and it is available in common foods. However, when individuals must deal with surgeries, infections and prolonged periods of stress, its supplementation may be necessary.

Benefits
As a supplement, glutamine is seen as both a ‘brain food’ and a muscle mass enhancer for body builders. Physicians have been known to use it for the treatment of alcoholism, mild depression and muscle-wasting conditions such as Huntington’s disease. This substance is actually the most common free-form amino acid found floating in muscle tissues. During times of stress, the body may draw glutamine away from the muscles in order to bolster the immune system or prevent blood sugar reactions. This is why many bodybuilders and other proponents of supplements often add daily doses to maintain good muscle health.

Sources
Glutamine is found in beef, poultry, fish and diary products. It is also found in vegetables high in fiber (wheat, cabbage, beets and beans). The acid has many immunity properties and can be a source of energy for the muscles and brain, as well as assist muscle building. These properties are why it is used to treat mental retardation, ADHD, and depression, as well as build muscle for weightlifters. Glutamine-S (C8H15N3O4, also known as Alanyl-glutamine or L-Alanyl-L-Glutamine) serves as nutrition supplementation at the same time.

Considerations
The average diet provides anywhere from 5 to 8 grams of glutamine a day. It would not be unusual for bodybuilders in training to boost this level to 10 grams or more with its supplements. Others who need to control blood sugar levels may also benefit from additional product. Some non-scientific studies suggest that the acid may also help improve mental function, because the body naturally uses it to transport nitrogen to the brain and nervous system. Higher doses may cause unpleasant side effects such as diarrhea, but most healthy bodies can safely assimilate the excess amino acid.

Iron Fact Sheets

发表于 2012 年 5 月 10 日由 21food

Iron, labeled as “Fe,” is the twenty-sixth element on the periodic table of elements, which means it has an atomic number of 26. It is a very common metallic element that is used in manufacturing processes and composes many different items. You probably interact with iron in numerous alloys and forms every day, since the element is a ubiquitous part of life on Earth.

History
Iron was first extracted from various metal ores that contained the element through a process of smelting that was developed in India during the beginning of the second millennium. Cast iron, which is easier to melt and mold, was created first in China in 550 BCE, and then found its way into Europe during the medieval period. This is also when wrought iron, which is pure iron, was first mined and sold in abundance.

Identification
Pure iron is a silvery white, very lustrous metal. It is extremely malleable and ductile, which is one of the reasons it has been used by humans for so long, since iron does not require complex technology to be worked. The nucleus of an iron atom contains 26 protons, which are positively charged particles. Electrons, which are negatively charged, are found in four different valence shells and total 26 as well. Found in nature, iron is a heavy metal with a smooth, silvery finish.

Because iron will remain magnetized even after a magnetic object is removed from its vicinity, it is considered ferromagnetic. Several metals demonstrate this property, and they have many useful qualities; not least as refrigerator magnets. The magnetic properties of iron have been a useful tool in studying the history of the Earth, as ancient iron particles in rock have aligned in different directions over thousands of years, reflecting changes in the magnetic field of the Earth.

Geography
On Earth, iron does not appear in a pure form; it can be found in compounds with other rocks known as ores. Iron is found not only on the Earth, but also in most of the more dense, solid masses in the galaxy. This includes other planets as well as moons and meteors. On Earth, iron is the most abundant element, and it can be found mainly in the Earth’s crust. Iron is abundant on the planet Mars, and is believed to give the planet its red color. 2,2′-Dipyridyl(C10H8N2, CAS No. 366-18-7) is used as a reagent for the determination of iron.

In Body
Humans and many other living organisms require iron for well being. Dietary iron can be found in red meat, dark leafy greens, dried fruit, beans, nuts, and seeds. A deficiency of iron can lead to anemia, a serious medical condition. Too much dietary iron can cause diarrhea, stomach cramps, and other symptoms; iron poisoning in children is an issue in some regions, usually because children eat iron pills intended for adults.

Medicinal Uses Of Baryta Carbonica

发表于 2012 年 5 月 10 日由 21food

Baryta carbonica is a type of homeopathic remedy widely used to treat children and the elderly who are suffering from a huge variety of symptoms generally encompassing physical, emotional and mental impairments. It is also known as Barium carbonate, Bar-C and Baryta-carb. It is a chemical compound also used in rat poison, bricks, ceramic glazes and cement. This barium carbonate remedy is thus taken from mineral barite and witherite found mainly in ancient rocks.

History
The mineral is named after William Withering, who in 1784 recognized it to be chemically distinct from barytes. It occurs in veins of lead ore at Hexham in Northumberland, Alston in Cumbria, Anglezarke, near Chorley in Lancashire and a few other localities. Witherite is readily altered to barium sulfate by the action of water containing calcium sulfate in solution and crystals are therefore frequently encrusted with barytes. It is the chief source of barium salts and is mined in considerable amounts in Northumberland.

Identification
Witherite crystallizes in the orthorhombic system. The crystals are invariably twinned together in groups of three, giving rise to pseudo-hexagonal forms somewhat resembling bipyramidal crystals of quartz, the faces are usually rough and striated horizontally. Preparations of Baryta carbonica are in the forms of granules, tablets and pellets which are available in many pharmacies.

Uses
Elderly people requiring Baryta carbonica(BaCO3, CAS No. 513-77-9) frequently have senile dementia, a disorder showing deterioration of mental abilities usually associated with getting old. Stroke and Alzheimer’s disease are the two most common causes of senile dementia. Symptoms include loss of memory, short attention span, confusion, language difficulties, irritability and impaired judgment.

Children who usually benefit from Barium carbonate exhibit delayed growth development and mental retardation. Physically, they show abnormally large and bulging abdomens, big heads, and limbs and genitals that are small for their ages. Trisomy 21, commonly known as Down’s syndrome, and dwarfism are some of the medical conditions treated with Baryta carbonica. These individuals usually manifest with walking difficulty, slow thinking process and poor social skills.

Timidity, shyness, lack of self-confidence and indecision are some of the emotional problems which can be helped with Baryta carbonica homeopathic remedy. The profile of individuals often needing Barium carbonate are those who appear immature and have underdeveloped personalities. Homeopathic practitioners usually prescribe the remedy after determining the needs of the patients.

The Research On Peptidomimetics

发表于 2012 年 5 月 10 日由 21food

Many research groups, both in academia and in pharmaceutical companies search constantly for non-peptide compounds that have better bioavailability and stability, perhaps even with greater receptor selectivity. A peptidomimetic is a compound that is designed to mimic a biologically active peptide, but has structural differences that give greater advantages for its function as a drug. For instance, a peptidomimetic that is designed to mimic a hormone would have greater stability and be more available to its target receptor to transmit signals.

Peptidomimetics were first designed to limit the conformational mobility of the peptide — in other words, the degree to which it can bend. Having peptides fixed in place makes it more likely that they will react with their desired target and limits undesirable side effects. Another goal is to increase their stability. The incorporation of unnatural compounds into their backbone makes it much less likely that these novel compounds will be degraded by the enzymes that break down peptides and peptidomimetics.

There are many instances where the native information within a natural peptide ligand can be conferred/duplicated or mimetized into a non-peptide molecule, preferably of low molecular weight, hence the basis for the field of peptidomimetics(PM’s). The desire to convey the three dimensional information present in a peptide into small nonpeptide molecules is what encompasses the field of peptidomimetics.

The reason for the interest in peptides is that many have significant biological activity. This means they can act as hormones and signal molecules for the central nervous system and the immune system. Peptides can affect a wide range of cellular activity, among them digestion, reproduction, and sensitivity to pain. Many peptide activities are of interest as targets for drugs, but it can be difficult for them to cross the membrane to enter a cell. Also, peptides that do make it into a cell are frequently unstable.

There are a number of factors that help in the rational design of PM’s such us: binding site optimal fit, conformational stabilization, (given by rigid elements and the positioning of specific functional groups), polar or hydrophobic regions (inside strategic reactive pockets) that favor the basic atomic interactions provided by hydrogen , electrostatic and hydrophobic bonding. BOC-D-Alanine (CAS No. 7764-95-6) is an unnatural amino acid mainly used for the synthesis of peptidomimetics.

The field of peptidomimetic design crosses a number of scientific disciplines. The success rate for identifying biologically-active compounds from libraries of peptidomimetic compounds is much higher than that from screening libraries of peptides. With the frequent advantages of increased stability and availability to their target, the field of peptidomimetics is growing.