Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023241 (Legionella)
 6,990 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Medical science has made tremendous strides in overcoming infectious diseases in the 20th century. Despite this, several epidemics of previously unrecognized diseases have occurred during the last 15 years. These diseases include Lyme disease, Legionnaires' disease, toxic shock syndrome, and AIDS. Examination of past epidemics, including the plague of Athens, the black death, syphilis, and influenza, suggests that the sudden occurrence of diseases that were previously unrecognized is not unusual. Analysis of the new infectious disease indicates that while all four appeared suddenly, isolated cases of the disease occurred before the actual epidemic. Further, all four new diseases were found to be due to agents or toxins that were not previously recognized. Epidemics due to new infectious diseases may arise by several mechanisms, including mutation of the pathogen to a virulent form and introduction of an infectious agent into a nonimmune population. Environmental and behavioral factors may play an important role, as illustrated by toxic shock syndrome, Legionnaires' disease, and AIDS. On the other hand, epidemic diseases tend to abate over time because of changes in the infecting pathogen and in the host. Hence, epidemics can be seen as cycles; new diseases will arise periodically, occasionally with a devastating outcome. With time the effects of these diseases on the population will ameliorate. The cycle will begin again when a new disease emerges.
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PMID:Plagues--what's past is present: thoughts on the origin and history of new infectious diseases. 192 88

THC, the major psychoactive component of marijuana, has been shown both in humans and experimental animals to have immunomodulatory properties. For example, marijuana smokers may show impaired immunological functions, including deficiency of blood leukocyte blastogenesis to mitogens. Detailed studies with mice have shown that animals given THC can show marked immunomodulation, including suppression of antibody formation, deficient cytokine production, etc. However, recent studies have also shown that lymphoid cells evince enhanced production or release or IL1, but suppression of IL2 and interferon production. Such lymphoid cells treated in vitro with THC also show suppressed blastogenesis to antigens and mitogens, suppressed NK activity, etc. In contrast, it has recently been shown that THC can enhance production or release of pro-inflammatory cytokines. This includes release of these cytokines from macrophages, including augmented release of IL1, TNF alpha, and IL6 activity. Susceptibility of mice to infection with opportunistic organisms such as L. pneumophila has been found and this increased susceptibility can be modulated by THC. A toxic shock-like death to Legionella has been induced by THC treatment given one day before and one day after infection. Receptors to THC have been detected in the brain as well as in peripheral tissues, including lymphoid cells. Thus, immunomodulation induced by THC may be related to receptor effects as well as unrelated to such receptors. It is clear that THC and other cannabinoids are excellent tools for studying the mechanisms of immune modulation, especially altered susceptibility to microbial infection.
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PMID:Marijuana, receptors and immunomodulation. 766 40

The Department of Health and Human Services (DHHS) has played a critical lead role over the past two years in fostering activities associated with the medical and public health response to bioterrorism. Based on a charge from Secretary Donna Shalala in 1998, the Centers for Disease Control and Prevention (CDC) is leading public health efforts to strengthen the nation's capacity to detect and respond to a bioterrorist event. As a result of our efforts, federal, state, and local communities are improving their public health capacities to respond to these types of emergencies. For many of us in public health, developing plans and capacities to respond to acts of bioterrorism is an extension of our long-standing roles and responsibilities. These are stated in the CDC Mission Statement: to promote health and quality of life by preventing and controlling disease, injury, and disability, and the Bioterrorism Mission: to lead the public health effort in enhancing readiness to detect and respond to bioterrorism. CDC's infectious diseases control efforts are summarized below: --Initially formed to address malaria control in 1946; --Established the epidemic Intelligence Service in 1951; --Participated in global smallpox eradication and other immunization programs; --Estimated 800-1,000 + field investigations/year since late 1990s; --New diseases: Legionnaire's Disease, toxic shock syndrome, Lyme disease, HIV, hantavirus pulmonary syndrome, West Nile, etc. -- Today: focus on emerging infections and bioterrorism. Over the past 50 years, CDC has seen a decline in the incidence of some infectious diseases and an increase in some, whereas others continue to present on a more unpredictable basis (i.e., hantavirus). Outbreak identification, investigation, and control have been an integral part of what we do for more than 50 years. We estimate that 800 to 1,000 field investigations have occurred every year since the late 1990s. Today, however, we have a new focus on emerging infectious diseases and bioterrorism.
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PMID:CDC's strategic plan for bioterrorism preparedness and response. 1188 Jun 62

Data on postmortem examination of five patients deceased during Legionnaires' outbreak in town Verkhnyaya Pyshma are presented in the article. Feature of course of the disease was severe affection of the lungs with development of toxic shock. Pathomorphological picture in lungs was characterized by polymorphism, presence of shock reaction and ventilator-associated pneumonia (atelectases, distelectases, tracheobronchitis). In autopsy material from four fatal cases Legionella pneumophila serogroup 1 was detected. Causative agent of pneumonia was not determined in one fatal case although comparison of clinical and morphological characteristics of this case with other four cases as well as detection of Gram-negative bacillus in alveolar macrophages allowed to consider this case of pneumonia as caused by Legionella. In studied fatal cases postmortem diagnoses were ascertained in which main disease was bilateral pneumonia caused by Legionella pneumophila serogroup 1 complicated by toxic shock.
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PMID:[Pathologic anatomy of pneumonia caused by Legionella: on the materials of outbreak in town Verkhnyaya Pyshma]. 1846 92