Cracked corners of lips can have several causes Milwaukee Journal Sentinel, WI - Aug 3, 2008 Iron deficiency, B vitamin deficiencies, yeast or staph infection, frequent lip licking, drooling at night, and irritation from facial products are some of ...
Is There (a Sex) Life After Herpes? Nurse.com, VA - Jul 28, 2008 Herpes is a virus of the herpes simplex family that has more than 80 different strains. Eight of those strains are responsible for human herpes infection, ...
Risk Factors for Recent HIV Infection in Uganda Journal of American Medical Association (subscription), IL - Aug 3, 2008 In multivariate analysis, risk factors associated with recent HIV infection included female sex (adjusted odds ratio [aOR], 2.4; 95% confidence interval ...
Do Cholesterol Medicines Really Work? RedOrbit, TX - Jul 29, 2008 The doctor said it was probably roseola, a herpes infection. The baby was never very sick, but I wonder if this roseola can cause future trouble. Can it? ...
Universal Access to HIV/AIDS Treatment Journal of American Medical Association (subscription), IL - Aug 3, 2008 Other biomedical interventions, including topical vaginal microbicides and suppressive treatment of infection with herpes simplex virus type 2, ...
Herpes Simplex Virus Types 1 and 2 Completely Help Adenovirus-Associated Virus Replication - RML Buller, JE Janik, ED Sebring, JA Rose - Journal of Virology, 1981 - pubmedcentral.nih.gov ... Types 1 and 2 Completely Help Adenovirus-Associated ... study, however, we show that herpes simplex virus ... at corresponding multiplicities of infection, AAV1 grew ...
Herpes zoster and human immunodeficiency virus infection - SP Buchbinder, MH Katz, NA Hessol, JY Liu, PM O? … - J Infect Dis, 1992 - Mass Med Soc ... General Medicine>; Summary and Comment. HERPES ZOSTER AND HIV INFECTION. ... Buchbinder
SP, et al. Herpes zoster and human immunodeficiency virus infection. ...
Interleukin-18 Protects Mice against Acute Herpes Simplex Virus Type 1 Infection - N Fujioka, R Akazawa, K Ohashi, M Fujii, M Ikeda, … - Journal of Virology, 1999 - Am Soc Microbiol JVI Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents ...
Interleukin-18 Protects Mice against Acute Herpes Simplex Virus Type 1 Infection. ...
The natural history of herpes simplex virus infection of mother and newborn - RJ Whitley, AJ Nahmias, AM Visintine, CL Fleming, … - Pediatrics, 1980 - Am Acad Pediatrics ... The natural history of herpes simplex virus infection of mother and newborn. ... Rev.
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Herpes Infection May Help To Fight Off Some Bacteria
Mice with chronic herpes virus infections can better resist the bacterium that causes plague and a bacterium that causes one kind of food poisoning, researchers report in this week's Nature.
Scientists at Washington University School of Medicine in St. Louis attributed the surprising finding to changes in the immune system triggered by the long-term presence of a latent herpes virus infection. In latent viral infections, the virus is present for the lifetime of the host in a relatively quiescent form that does not cause overt symptoms.
While presenting their results, researchers stressed that they did not want to minimize or in any way disregard the human suffering and health risks caused by disease-causing herpes infections. But they noted that several strains of herpes viruses found in much of the human population remain symptom-free throughout the host's lifetime.
"Our results suggest that we should look at whether humans receive similar advantages from these and other chronic infections that do not cause active disease," says senior author Herbert W. "Skip" Virgin, M.D., Ph.D., head of the Department of Pathology and Immunology. "If so, that has public health implications because we would want to very carefully weigh the risks and benefits of eliminating a virus that our bodies have established a symbiotic relationship with."
Article continues below and (thank you)
Scientists previously used vaccination to eliminate the deadly and highly contagious smallpox virus. Vaccines are currently in use or in clinical trials for several disease-causing strains of herpes.
Human herpes viruses include oral and genital herpes, the chickenpox virus, cytomegalovirus, Epstein-Barr virus and Kaposi's sarcoma-associated herpes virus. During an initial period of acute infection, many of these viruses cause symptoms, such as fever, cold sores or blisters. They then enter periods of latency. Sometimes symptoms never recur; sometimes they flare up periodically before becoming quiescent again. In addition, less infamous herpes viruses like HHV6 and HHV7 permanently infect most humans without ever producing any significant symptoms.
The results have potentially wide-reaching implications for immune research. Humans and other mammals have spent millions of years living and evolving with latent viral infections, Virgin notes, and the new results imply that infections may have altered our immune systems at a fundamental level. This could mean the virus-free animal models scientists use to study vaccines, autoimmune diseases, and other immune system issues have the potential to produce misleading results.
"Chronic virus infections may in part define what a normal human immune response is," says Virgin, who is the Edward Mallinckrodt Professor of Pathology and Immunology. "We may need to think about that as we consider the implications animal model results hold for human diseases."
Scientists have recognized for years that many types of bacteria and other microorganisms live in the human gut to the advantage of both the microbes and their human hosts. The results from the Virgin lab are among the first to suggest the potential for symbiotic benefits from viral infections that live in areas beyond epithelial surfaces like the skin, throat or intestines.
For the new research, Virgin's group worked with strains of mouse herpes virus closely related to human Epstein-Barr virus, Kaposi's sarcoma-associated herpes virus and cytomegalovirus. During studies of how mouse herpes viruses transition from acute to latent infections, Virgin made a discovery that piqued his interest in the possibility that latent infections might confer unrecognized benefits.
"We found evidence that the mouse immune system controls latent herpes infections in part by increasing production of a protein hormone called interferon gamma," Virgin says. "This is a signaling hormone that in effect puts some immune system soldiers on yellow alert, causing them to patrol for invaders with their eyes wide open and defense weapons ready."
Other scientists previously had shown that interferon gamma helps the immune system fight off some strains of bacteria. This led Virgin and his colleagues to test herpes-infected mice with exposure to the bacteria Yersinia pestis, which causes plague, and Listeria monocytogenes, which is a minor cause of food poisoning and can infect the central nervous system. Many aspects of Listeria infection in mice are also similar to those that occur in humans infected with tuberculsis. They found that when mice had a latent herpes infection, the bacteria replicated more slowly and were less likely to kill the mice.
When herpes was still in the acute phase of infection, no protective effect was present. When scientists exposed the mice to a mutant herpes virus that can infect but cannot establish latency, the herpes infection did not confer resistance. The protective effect could be produced by two different mouse herpes viruses.
"We have a good feel for who the main players are in this protective effect, but we need further research to better understand the exact mechanisms that underlie the process," Virgin says.
He suspects that the virus may be prompting the immune system to produce more interferon gamma to keep itself from emerging from latency. If the virus stays latent, it prevents itself from seriously endangering the host and can continue to spread to new hosts from its current perch.
"We need to explore whether there are additional costs and benefits to the host from this," Virgin says. "Are there additional pathogens that find it harder to come in as a secondary infection after herpes becomes latent" Do other latent infections convey similar protective effects" These are not the kinds of questions we're accustomed to asking about such infections, but our findings suggest that we need to start."
Virgin notes that human and mouse herpes viruses are genetically very closely related. The similarity strongly suggests that modern herpes viruses are likely descended from herpes viruses that infected evolutionary ancestors common to both mice and humans.
"That means that for as long as we've been human, these viruses have been with us," he says. "In that respect - given the millions and millions of years that mammalian immune systems have had to adapt to these viruses - perhaps these results are not as surprising as they might seem at first."
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Barton ES, White DW, Cathelyn JS, Brett-McClellan KA, Engle M, Diamond MS, Miller VL, Virgin IV HW. Herpesvirus latency protects the host from bacterial infection: latency as mutualistic symbiosis. Nature, May 17, 2007.
Funding from the National Institutes of Health supported this research. Washington University School of Medicine's full-time and volunteer faculty physicians also are the medical staff of Barnes-Jewish and St. Louis Children's hospitals. The School of Medicine is one of the leading medical research, teaching and patient care institutions in the nation, currently ranked fourth in the nation by U.S. News & World Report. Through its affiliations with Barnes-Jewish and St. Louis Children's hospitals, the School of Medicine is linked to BJC HealthCare.
Pollutants, food ingredients, solvents may all cause harm, researchers say.
By Alan Mozes HealthDay Reporter
MONDAY, May 14 (HealthDay News) -- A detailed analysis of hundreds of completed breast cancer studies has linked disease development with environmental exposure to more than 200 chemical compounds.
The finding is part of an effort to build a free, online breast cancer database for researchers and the public.
Described as "the most comprehensive of its kind," the database will highlight growing concern about environmental carcinogens such as pollutants, food contaminants, and organic solvents. The scope of the project will also extend to work that explores risk-related lifestyle factors such as diet, levels of physical activity, smoking/drinking habits and body mass.
"This compilation is a great effort, because it summarizes all the evidence and gives us hints of what to look for next," explained researcher Leslie Bernstein, a professor of preventive medicine with the Keck School of Medicine at the University of Southern California in Los Angeles.
The results are outlined in a supplement to the May 14th online issue of Cancer. The database is already accessible at either www.silentspring.org/sciencereview or www.komen.org/environment.
According to the American Cancer Society (ACS), carcinogens are defined as agents that instigate abnormal cell division or harmful changes in the structure of a cell's DNA. They include chemicals, radiation, or infectious agents, among other things.
The ACS also notes that with the exception of skin cancer, breast cancer is the most common cancer among American women. This year, almost 179,000 women in the United States will be diagnosed with the disease, and about 40,000 will die.
The International Agency of Research on Cancer has already classified 90 or so compounds as human carcinogens, according to the ACS. But Bernstein's team said that most of the chemicals to which people are routinely exposed have not undergone any testing for carcinogenic risk. An estimated 80,000 chemicals are registered in the United States for commercial use, according to the researchers.
For more than two years, Bernstein worked alongside colleagues from Harvard University, the Roswell Park Cancer Institute, and the Silent Spring Institute to amass and sort through approximately 900 national and international breast cancer studies focused on carcinogens.
The team honed in on 460 human breast cancer studies, of which more than 150 looked at specific environmental carcinogens among breast cancer patients. Most of those studies were conducted in the 1990s.
The remaining studies involved animal or laboratory research. The researchers pointed out that animal studies are valid references, because all known human carcinogens have also triggered tumors in animal subjects.
In the animal studies alone, evidence surfaced that linked 216 chemicals to the onset of breast tumors. These included 36 industrial chemicals, 6 chlorinated solvents, 18 products of combustion, 10 pesticides, 18 dyes, four type of radiation, 47 pharmaceuticals, and 17 hormones.
Of these compounds, the researchers isolated 73 that can be found in either human food or consumer products.
They noted, for example, the lingering hazards associated with polychlorinated biphenyls (or PCBs), which were typically used in the production of electrical equipment until federally banned in 1979. PCBs continue to pose a risk via contaminated rivers, fish, and pre-existing building construction, the researchers warned.
In addition, the authors categorized 35 compounds as carcinogenic air pollutants, including polycyclic aromatic hydrocarbons (or PAHs), which are byproducts of combustion.
The team also drew attention to another group of 25 organic compounds, including dioxins, which are produced by waste incineration and manufacturing. These carcinogenic chemicals are present in many American workplaces and place more than 5,000 women at an increased risk for breast cancer, the researchers said. These include women working in machine shops, dry cleaners, hairdressers, glass manufacturers, and aircraft maintenance facilities, all of which use harmful organic solvents.
Furthermore, among the identified carcinogens, 29 are produced in large amounts -- upwards of one million pounds or more per year.
The database project did not set strict guidelines as to how to limit exposure to carcinogens. But the authors said they encouraged research and government oversight into the problem. They advised that people do try and limit their exposure to PCB-contaminated fish, gasoline-generated air pollution, chlorinated tap water, non-stick coated cookware, and detergents containing fluorescent whiteners.
Just how carcinogenic, in terms of breast cancer risk, are these and other compounds on the list? The jury is still out on that question, Bernstein said.
"Women are terribly concerned about environmental causes of breast cancer," she said. "But it's really very difficult to study. Often the only way we've been able to look at some of these things is during occupational exposures or accidents -- what we usually call disasters."
"So, this work is a very useful tool for those of us who want to try to understand what we've missed in breast cancer. Now, it's up to us to do something with all this information," Bernstein said.
Janet Gray, a professor of psychology and the director of the program in science, technology and society at Vassar College in Poughkeepsie, N.Y., called the new database "an enormous contribution."
"Its greatest value is just the sheer comprehensive nature of the work, which allows both the public and researchers to have access to huge amounts of information in one place," she said. "I think this effort will really move us forward."
Known and Probable Carcinogens
Including Industrial Processes, Occupational Exposures, Infectious Agents, Chemicals, and Radiation)
What Is a Carcinogen?
Cancer is caused by abnormalities in a cell’s DNA (its genetic "blueprint"). These may be inherited from parents, or they may be caused by outside exposures to the body such as chemicals, radiation, or even infectious agents.
Substances that can cause changes that can lead to cancer are called carcinogens. Some carcinogens do not act on DNA directly, but lead to cancer in other ways, such as causing cells to divide at a faster rate, which could increase the chances that DNA changes will occur.
Carcinogens do not cause cancer in every case, all the time. Substances classified as carcinogens may have different levels of cancer-causing potential. Some may cause cancer only after prolonged, high levels of exposure. And for any particular person, the risk of developing cancer depends on many factors, including the length and intensity of exposure to the carcinogen and the person’s genetic makeup.
How Do We Determine if Something Is a Carcinogen? Scientists get much of their data about whether something might cause cancer from laboratory (cell culture and animal) studies. Although it isn’t possible to predict with certainty which substances will cause cancer in humans based on animal studies alone, virtually all known human carcinogens that have been adequately tested produce cancer in lab animals. In many cases, carcinogens are first found to cause cancer in lab animals and are later found to cause cancer in people. Because there are far too many substances (natural and manmade) to test each one in lab animals, scientists use knowledge about chemical structure, other types of lab tests, and information about the extent of human exposure to select chemicals for testing.
Most studies of potential carcinogens expose the lab animals to doses that are higher than common human exposures. This is so that cancer risk can be detected in relatively small groups of animals. For most carcinogens, it is assumed that those that cause cancer at larger doses in animals will also cause cancer in people. Although it isn’t always possible to know the relationship between exposure dose and risk, it is reasonable for public health purposes to assume that lowering human exposure will reduce risk.
Another important way to identify carcinogens is through epidemiologic studies, which look at human populations to determine which factors might be linked to cancer. While these studies also provide useful information, they also have their limitations. Humans do not live in a controlled environment. People are exposed to numerous substances at any one time, including those they encounter at work, school, or home; in the food they eat; and the air they breathe. And it is usually many years (often decades) between exposure to a carcinogen and the development of cancer. Therefore, it can be very hard to single out any particular exposure as having a definite link to cancer.
By combining data from both types of studies, scientists are able to make an educated assessment of a substance’s cancer-causing ability. When the available evidence is compelling but not felt to be conclusive, the substance may be considered to be a probable carcinogen.
How Are Carcinogens Classified?
International Agency for Research on Cancer (IARC)
The most widely used system for classifying carcinogens comes from the IARC, which is part if the World Health Organization (WHO). In the past 30 years, the IARC has evaluated the cancer-causing potential of about 900 likely candidates, placing them into one of the following groups:
Group 1: Carcinogenic to humans
Group 2A: Probably carcinogenic to humans
Group 2B: Possibly carcinogenic to humans
Group 3: Unclassifiable as to carcinogenicity in humans
Group 4: Probably not carcinogenic to humans
Perhaps not surprisingly, most of the agents are of probable, possible, or unknown risk. Only about 90 are classified as "carcinogenic to humans."
National Toxicology Program (NTP)
In the United States, the NTP releases the Report on Carcinogens about every 2 years. The NTP is formed from parts of several different government agencies, including the National Institutes of Health (NIH), the Centers for Disease Control and Prevention (CDC), and the Food and Drug Administration (FDA).
The Report on Carcinogens (RoC) identifies 2 groups of agents:
"Known to be human carcinogens"
"Reasonably anticipated to be human carcinogens"
Unlike the IARC’s list, the RoC does not list substances that have been studied and found not to be carcinogens. Below are the lists of known and probable human carcinogens from both groups.
Known Human Carcinogens
International Agency for Research on Cancer (IARC) "Carcinogenic to Humans" (Group 1)
Agents and Groups of Agents
Aflatoxins (naturally occurring mixtures of)
4-Aminobiphenyl
Arsenic and arsenic compounds (Note: This evaluation applies to the group of compounds as a whole and not necessarily to all individual compounds within the group)
Estrogens, nonsteroidal (Note: This evaluation applies to the group of compounds as a whole and not necessarily to all individual compounds within the group)
Estrogens, steroidal (Note: This evaluation applies to the group of compounds as a whole and not necessarily to all individual compounds within the group)
Ethylene oxide
Etoposide in combination with cisplatin and bleomycin
Formaldehyde
Gallium arsenide
Gamma radiation
Helicobacter pylori (infection with)
Hepatitis B virus (chronic infection with)
Hepatitis C virus (chronic infection with)
Herbal remedies containing plant species of the genus Aristolochia
Human immunodeficiency virus type 1 (infection with)
Human papillomavirus type 16
Human papillomavirus type 18
Human T-cell lymphotropic virus type I
Melphalan
8-Methoxypsoralen (Methoxsalen) plus ultraviolet A radiation
MOPP and other combined chemotherapy including alkylating agents
Mustard gas (Sulfur mustard)
2-Naphthylamine
Neutrons
Nickel compounds
Opisthorchis viverrini (infection with)
Oral contraceptives, combined (Note: There is also conclusive evidence that these agents have a protective effect against cancers of the ovary and endometrium)
Oral contraceptives, sequential
Phosphorus-32, as phosphate
Plutonium-239 and its decay products (may contain plutonium-240 and other isotopes), as aerosols
Radioiodines, short-lived isotopes, including iodine-131, from atomic reactor accidents and nuclear weapons detonation (exposure during childhood)
Radionuclides, alpha-particle-emitting, internally deposited (Note: Specific radionuclides for which there is sufficient evidence for carcinogenicity to humans are also listed individually as Group 1 agents)
Radionuclides, beta-particle-emitting, internally deposited (Note: Specific radionuclides for which there is sufficient evidence for carcinogenicity to humans are also listed individually as Group 1 agents)
Radium-224 and its decay products
Radium-226 and its decay products
Radium-228 and its decay products
Radon-222 and its decay products
Schistosoma haematobium (infection with)
Silica, crystalline (inhaled in the form of quartz or cristobalite from occupational sources)
Solar radiation
Talc containing asbestiform fibers
Tamoxifen (Note: There is also conclusive evidence that this agent (tamoxifen) reduces the risk of contralateral breast cancer)
2,3,7,8-Tetrachlorodibenzo-para-dioxin
Thiotepa
Thorium-232 and its decay products, administered intravenously as a colloidal dispersion of thorium-232 dioxide
Treosulfan
Vinyl chloride
X- and Gamma radiation
Mixtures
Alcoholic beverages
Analgesic mixtures containing phenacetin
Areca nut
Betel quid with tobacco
Betel quid without tobacco
Coal-tar pitches
Coal-tars
Mineral oils, untreated and mildly treated
Salted fish (Chinese-style)
Shale-oils
Soots
Tobacco products, oral tobacco products
Wood dust
Exposure Circumstances
Aluminum production
Arsenic in drinking water
Auramine, manufacture of
Boot and shoe manufacture and repair
Coal gasification
Coke production
Furniture and cabinet making
Hematite mining (underground) with exposure to radon
