quinta-feira, 22 de janeiro de 2015

Humidifiers - Mayo Clinic

 

 

Humidifiers: Air moisture eases skin, breathing symptoms

Humidifiers can ease problems caused by dry air. But they need regular maintenance. Here are tips to ensure your humidifier doesn't become a household health hazard. By Mayo Clinic Staff

Dry sinuses, bloody noses and cracked lips — humidifiers can help soothe these familiar problems caused by dry indoor air. Humidifiers can also help ease symptoms of a cold or another respiratory condition.

But be cautious: Although useful, humidifiers can actually make you sick if they aren't maintained properly or if humidity levels stay too high. If you use humidifiers, be sure to monitor humidity levels and keep your humidifier clean. Dirty humidifiers can breed mold or bacteria. If you have allergies or asthma, talk to your doctor before using a humidifier.

What are humidifiers?

Humidifiers are devices that emit water vapor or steam to increase moisture levels in the air (humidity). There are several types:

  • Central humidifiers are built into home heating and air conditioning systems and are designed to humidify the whole house.
  • Ultrasonic humidifiers produce a cool mist with ultrasonic vibration.
  • Impeller humidifiers produce a cool mist with a rotating disk.
  • Evaporators use a fan to blow air through a wet wick, filter or belt.
  • Steam vaporizers use electricity to create steam that cools before leaving the machine. Avoid this type of humidifier if you have children; hot water inside this type of humidifier may cause burns if spilled.
Ideal humidity levels

Humidity is the amount of water vapor in the air. The amount of humidity varies depending on the season, weather and where you live. Generally, humidity levels are higher in the summer and lower during winter months. Ideally, humidity in your home should be between 30 and 50 percent. Humidity that's too low or too high can cause problems.

  • Low humidity can cause dry skin, irritate your nasal passages and throat, and make your eyes itchy.
  • High humidity can make your home feel stuffy and can cause condensation on walls, floors and other surfaces that triggers the growth of harmful bacteria, dust mites and molds. These allergens can cause respiratory problems and trigger allergy and asthma flare-ups.
How to measure humidity

The best way to test humidity levels in your house is with a hygrometer. This device, which looks like a thermometer, measures the amount of moisture in the air. Hygrometers can be purchased at hardware stores and department stores. When buying a humidifier, consider purchasing one with a built-in hygrometer (humidistat) that maintains humidity within a healthy range.

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Humidifiers, asthma and allergies

If you or your child has asthma or allergies, talk to your doctor before using a humidifier. Increased humidity may ease breathing in children and adults who have asthma or allergies, especially during a respiratory infection such as a cold. But dirty mist or increased growth of allergens caused by high humidity can trigger or worsen asthma and allergy symptoms.

When the air's too damp: Dehumidifiers and air conditioners

Just as air that's dry can be a problem, so can air that's too moist. When humidity gets too high — common during summer months — it's a good idea to take steps to reduce indoor moisture. There are two ways to reduce humidity:

  • Use an air conditioner. Central or window-mounted air conditioning units dry the air, keeping indoor humidity at a comfortable and healthy level.
  • Use a dehumidifier. These devices collect excess moisture from the air, lowering humidity levels. Dehumidifiers work like air conditioners, without the "cooling" effect. They're often used to help dry out damp basements.
Keep it clean: Dirty humidifiers and health problems

Dirty reservoirs and filters in humidifiers can quickly breed bacteria and mold. Dirty humidifiers can be especially problematic for people with asthma and allergies, but even in healthy people humidifiers have the potential to trigger flu-like symptoms or even lung infections when the contaminated mist or steam is released into the air. Steam vaporizers or evaporators may be less likely to release airborne allergens than may cool-mist humidifiers.

Tips for keeping your humidifier clean

To keep humidifiers free of harmful mold, fungi and bacteria, follow the guidelines recommended by the manufacturer. These tips for portable humidifiers also can help:

  • Use distilled or demineralized water. Tap water contains minerals that can create deposits inside your humidifier that promote bacterial growth. And, when released into the air, these minerals often appear as white dust on your furniture. You may also breathe in some minerals that are dispersed into the air. Distilled or demineralized water has a much lower mineral content compared with tap water. In addition, use demineralization cartridges or filters if recommended by the manufacturer.
  • Change humidifier water often. Don't allow film or deposits to develop inside your humidifiers. Empty the tanks, dry the inside surfaces and refill with clean water every day if possible, especially if using cool mist or ultrasonic humidifiers. Unplug the unit first.
  • Clean humidifiers every three days. Unplug the humidifier before you clean it. Remove any mineral deposits or film from the tank or other parts of the humidifier with a 3 percent hydrogen peroxide solution, which is available at pharmacies. Some manufacturers recommend using chlorine bleach or other disinfectants.
  • Always rinse the tank after cleaning to keep harmful chemicals from becoming airborne — and then inhaled.
  • Change humidifier filters regularly. If the humidifier has a filter, change it at least as often as the manufacturer recommends — and more often if it's dirty. Also regularly change the filter in your central air conditioning and heating system.
  • Keep the area around humidifiers dry. If the area around a humidifier becomes damp or wet — including windows, carpeting, drapes or tablecloths — turn the humidifier down or reduce how frequently you use it.
  • Prepare humidifiers for storage. Drain and clean humidifiers before storing them. And then clean them again when you take them out of storage for use. Throw away all used cartridges, cassettes or filters.
  • Follow instructions for central humidifiers. If you have a humidifier built into your central heating and cooling system, read the instruction manual or ask your heating and cooling specialist about proper maintenance.
  • Consider replacing old humidifiers. Over time, humidifiers can build up deposits that are difficult or impossible to remove and encourage growth of bacteria.
May. 18, 2013
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Cholesterol medications: Consider the options

 

By Mayo Clinic Staff

A healthy lifestyle is the first defense against high cholesterol. But sometimes diet and exercise aren't enough, and you may need to take cholesterol medications. Cholesterol medications may help:

  • Decrease your low-density lipoprotein (LDL) cholesterol, the "bad" cholesterol that increases the risk of heart disease
  • Decrease your triglycerides, a type of fat in the blood that also increases the risk of heart disease
  • Increase your high-density lipoprotein (HDL) cholesterol, the "good" cholesterol that offers protection from heart disease

Your doctor may suggest a single drug or a combination of cholesterol medications. Here's an overview of benefits, cautions and possible side effects for common classes of cholesterol medications.

Drug class and drug names
Benefits
Possible side effects and cautions

Statins
Altoprev (lovastatin)
Crestor (rosuvastatin)
Lescol (fluvastatin)
Lipitor (atorvastatin)
Mevacor (lovastatin)
Pitavastatin (Livalo)
Pravachol (pravastatin)
Zocor (simvastatin)
Decrease LDL and triglycerides; slightly increase HDL
Constipation, nausea, diarrhea, stomach pain, cramps, muscle soreness, pain and weakness; possible interaction with grapefruit juice

Bile acid binding resins
Colestid (colestipol)
Questran (cholestyramine/ sucrose)
Welchol (colesevelam)
Decrease LDL
Constipation, bloating, nausea, gas; may increase triglycerides

Cholesterol absorption inhibitor
Zetia (ezetimibe)
Decreases LDL; slightly decrease triglycerides; slightly increase HDL
Stomach pain, fatigue, muscle soreness

Combination cholesterol absorption inhibitor and statin
Vytorin (ezetimibe-simvastatin)
Decreases LDL and triglycerides; increases HDL
Stomach pain, fatigue, gas, constipation, abdominal pain, cramps, muscle soreness, pain and weakness; possible interaction with grapefruit juice

Fibrates
Lofibra (fenofibrate)
Lopid (gemfibrozil)
TriCor (fenofibrate)
Decrease triglycerides; increase HDL
Nausea, stomach pain, gallstones

Niacin
Niaspan (prescription niacin)
Decreases LDL and triglycerides; increases HDL
Facial and neck flushing, nausea, vomiting, diarrhea, gout, high blood sugar, peptic ulcers

Combination statin and niacin
Advicor (niacin-lovastatin)
Decreases LDL and triglycerides; increases HDL
Facial and neck flushing, dizziness, heart palpitations, shortness of breath, sweating, chills; possible interaction with grapefruit juice

Omega-3 fatty acids
Lovaza (prescription omega-3 fatty acid supplement)
Vascepa (Icosapent ethyl)
Decrease triglycerides
Belching, fishy taste, increased infection risk

Most cholesterol medications lower cholesterol with few side effects, but effectiveness varies from person to person. If you decide to take cholesterol medication, your doctor may recommend periodic liver function tests to monitor the medication's effect on your liver. Also remember the importance of healthy lifestyle choices. Medication can help control your cholesterol — but lifestyle matters, too.

Aug. 26, 2014

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Trust your gut: E. coli may hold one of the keys to treating Parkinson's

 

Amyloids walk a tightrope: The net beneath the rope is a representation of the molecular structure of a protein called CsgC. CsgC can be likened to a safety net that catches amyloids and prevents them from formulating in a way that’s toxic to cells. When amyloid formation happens at the wrong place or time, it can be toxic to cells.

E. coli usually brings to mind food poisoning and beach closures, but researchers recently discovered a protein in E. coli that inhibits the accumulation of potentially toxic amyloids -- a hallmark of diseases such as Parkinson's.

Amyloids are formed by proteins that misfold and group together, and when amyloids assemble at the wrong place or time, they can damage brain tissue and cause cell death, according to Margery Evans, lead author of the University of Michigan study, and Matthew Chapman, principal investigator and associate professor in U-M Molecular, Cellular, and Developmental Biology.

The findings could point to a new therapeutic approach to Parkinson's disease and a method for targeting amyloids associated with such neurodegenerative diseases.

A key biological problem related to patients with Parkinson's is that certain proteins accumulate to form harmful amyloid fibers in brain tissues, which is toxic to cells and causes cell death.

While these amyloids are a hallmark of Parkinson's and other diseases such as Alzheimer's, not all amyloids are bad. Some cells, those in E. coli included, assemble helpful amyloids used for cell function.

E. coli make amyloid curli on the cell surface, where it's protective, rather than toxic. The curli anchor the bacteria to kitchen counters and intestinal walls, where they can cause infections and make us sick. These helpful amyloids that E. coli produce do not form on the inside of the cell where they would be toxic.

"It means that something in E. coli very specifically inhibits the assembly of the amyloid inside the cell. Therefore, amyloid formation only occurs outside the cell where it does not cause toxicity," said Evans, a doctoral student in molecular, cellular, and developmental biology.

Evans and the U-M team went on a biochemical hunt to understand how E. coli prevented amyloids from forming inside cells and uncovered a protein called CsgC that is a very specific, effective inhibitor of E. coli amyloid formation.

U-M researchers have been collaborating with scientists from Umeå University in Sweden and Imperial College in London, and in the current study found that the CsgC protein also inhibits amyloid formation of the kind associated with Parkinson's.

Another implication of the research is that the curli could be a target for attacking biofilms, a kind of goo created by bacteria, which acts as a shield to thwart antibiotics and antiseptics. These bacteria can cause chronic infections, but treating these infections using molecules that block curli formation may degrade the biofilm and leave the bacteria more vulnerable to drug therapy.

The study, "The bacterial curli system possesses a potent and selective inhibitor of amyloid formation," is scheduled to appear Jan. 22 in the online edition of Molecular Cell.

Evans, who conducted the research while at U-M will be a postdoctoral fellow at Washington University in St. Louis.


Story Source:

The above story is based on materials provided by University of Michigan. Note: Materials may be edited for content and length.


Journal Reference:

  1. Margery L. Evans, Erik Chorell, Jonathan D. Taylor, Jörgen Åden, Anna Götheson, Fei Li, Marion Koch, Lea Sefer, Steve J. Matthews, Pernilla Wittung-Stafshede, Fredrik Almqvist, Matthew R. Chapman. The Bacterial Curli System Possesses a Potent and Selective Inhibitor of Amyloid Formation. Molecular Cell, 2015; DOI: 10.1016/j.molcel.2014.12.025

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First major analysis of Human Protein Atlas is published

 

3D render of DNA structure (stock image). The approximately 20,000 protein coding genes in humans have been analysed and classified using a combination of genomics, transcriptomics, proteomics, and antibody-based profiling, says the article's lead author, Mathias Uhlén

A research article published in Science presents the first major analysis based on the Human Protein Atlas, including a detailed picture of the proteins that are linked to cancer, the number of proteins present in the bloodstream, and the targets for all approved drugs on the market.

The Human Protein Atlas, a major multinational research project supported by the Knut and Alice Wallenberg Foundation, recently launched (November 6, 2014) an open source tissue-based interactive map of the human protein. Based on 13 million annotated images, the database maps the distribution of proteins in all major tissues and organs in the human body, showing both proteins restricted to certain tissues, such as the brain, heart, or liver, and those present in all. As an open access resource, it is expected to help drive the development of new diagnostics and drugs, but also to provide basic insights in normal human biology.

In the Science article, "Tissue-based Atlas of the Human Proteome," the approximately 20,000 protein coding genes in humans have been analysed and classified using a combination of genomics, transcriptomics, proteomics, and antibody-based profiling, says the article's lead author, Mathias Uhlén, Professor of Microbiology at Stockholm's KTH Royal Institute of Technology and the director of the Human Protein Atlas program.

The analysis shows that almost half of the protein-coding genes are expressed in a ubiquitous manner and thus found in all analysed tissues.

Approximately 15% of the genes show an enriched expression in one or several tissues or organs, including well-known tissue-specific proteins, such as insulin and troponin. The testes, or testicles, have the most tissue-enriched proteins followed by the brain and the liver.

The analysis suggests that approximately 3,000 proteins are secreted from the cells and an additional 5,500 proteins are located to the membrane systems of the cells.

"This is important information for the pharmaceutical industry. We show that 70% of the current targets for approved pharmaceutical drugs are either secreted or membrane-bound proteins," Uhlén says. "Interestingly, 30% of these protein targets are found in all analysed tissues and organs. This could help explain some side effects of drugs and thus might have consequences for future drug development."

The analysis also contains a study of the metabolic reactions occurring in different parts of the human body. The most specialised organ is the liver with a large number of chemical reactions not found in other parts of the human body.


Story Source:

The above story is based on materials provided by KTH, Royal Institute of Technology. Note: Materials may be edited for content and length.


Journal Reference:

  1. M. Uhlen, L. Fagerberg, B. M. Hallstrom, C. Lindskog, P. Oksvold, A. Mardinoglu, A. Sivertsson, C. Kampf, E. Sjostedt, A. Asplund, I. Olsson, K. Edlund, E. Lundberg, S. Navani, C. A.-K. Szigyarto, J. Odeberg, D. Djureinovic, J. O. Takanen, S. Hober, T. Alm, P.-H. Edqvist, H. Berling, H. Tegel, J. Mulder, J. Rockberg, P. Nilsson, J. M. Schwenk, M. Hamsten, K. von Feilitzen, M. Forsberg, L. Persson, F. Johansson, M. Zwahlen, G. von Heijne, J. Nielsen, F. Ponten. Tissue-based map of the human proteome. Science, 2015; 347 (6220): 1260419 DOI: 10.1126/science.1260419

 

Blame it on your brain: Salt and hypertension

 

An international research team led by scientists at McGill University has found that excessive salt intake "reprograms" the brain, interfering with a natural safety mechanism that normally prevents the body's arterial blood pressure from rising.

While the link between salt and hypertension is well known, scientists until now haven't understood how high salt intake increased blood pressure. By studying the brains of rats, a team led by Prof. Charles Bourque of McGill's Faculty of Medicine discovered that ingesting large amounts of dietary salt causes changes in key brain circuits.

"We found that a period of high dietary salt intake in rats causes a biochemical change in the neurons that release vasopressin (VP) into the systemic circulation," says Bourque who is also a researcher at the The Research Institute of the McGill University Health Centre (RI-MUHC). "This change, which involves a neurotrophic molecule called BDNF (brain-derived neurotrophic factor), prevents the inhibition of these particular neurons by other cells."

The team's findings, published in the journal Neuron, found that high salt intake prevents the inhibition of VP neurons by the body's arterial pressure detection circuit. The disabling of this natural safety mechanism allows blood pressure to rise when a high amount of salt is ingested over a long period of time.

While the team's discovery advances the understanding of the link between salt intake and blood pressure, more work is needed to define new targets that could potentially be explored for therapeutic intervention. Among the questions for further research: Does the same reprogramming effect hold true for humans? If so, how might it be reversed?

In the meantime, Bourque says, the message remains: limit dietary salt.


Story Source:

The above story is based on materials provided by McGill University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Katrina Y. Choe, Su Y. Han, Perrine Gaub, Brent Shell, Daniel L. Voisin, Blayne A. Knapp, Philip A. Barker, Colin H. Brown, J. Thomas Cunningham, Charles W. Bourque. High Salt Intake Increases Blood Pressure via BDNF-Mediated Downregulation of KCC2 and Impaired Baroreflex Inhibition of Vasopressin Neurons. Neuron, 2015; DOI: 10.1016/j.neuron.2014.12.048