Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0017160 (gastroenteritis)
 11,398 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Many discriminative experimental animal models of infection have been utilized in the evaluation of newer fluoroquinolones. In vivo efficacy of many of the newer agents has been shown in experimental models of meningitis, endocarditis, pneumonia, urinary tract infections, pyelonephritis, osteomyelitis, abscesses of various types, septic arthritis, gastroenteritis, salmonellosis, listeriosis, tuberculosis, syphilis, sinusitis, prostatitis and burn wound sepsis, among others. This review focuses on recent developments in a few selected areas. Although the limitations of animal model studies are well described, these results provide a rationale for the appropriate clinical usage of the newer fluoroquinolones in humans.
 ...
PMID:Evaluation of quinolones in experimental animal models of infections. 186 88

Recent work by epidemiologists and microbiologists has uncovered several hitherto unrecognized food-borne bacterial pathogens of public health significance. One of these, Listeria monocytogenes, has attracted considerable attention because of two major cheese-related outbreaks of listeriosis that were characterized by cases of meningitis, abortion, and perinatal septicemia. Thus far, L. monocytogenes has been responsible for well over 300 reported cases of food-borne listeriosis, including about 100 deaths, and has cost the dairy industry alone more than 66 million dollars as a result of product recalls. The ability of L. monocytogenes to grow at refrigeration temperatures, coupled with appearance of the pathogen in raw and processed meats, as well as poultry, vegetables, and seafood, makes this bacterium a serious threat to susceptible consumers and to the entire food industry. Yersinia enterocolitica, another psychrotrophic food-borne pathogen of recent concern, was linked to several outbreaks of yersiniosis associated with consumption of both raw and pasteurized milk, as well as contaminated water. Food-borne infections involving Y. enterocolitica typically result in enterocolitis, which may be mistaken for acute appendicitis. Unfortunately, inadvertent removal of healthy appendixes from victims of food-borne yersiniosis is all too common. Although known for many years, Campylobacter jejuni has only recently been recognized as a food-borne pathogen and a leading cause of gastroenteritis in the United States. Notable outbreaks of campylobacteriosis linked to consumption of raw milk, cake icing, eggs, poultry, and beef have underscored the need for thorough cooking and proper handling of raw products.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:"New" food-borne pathogens of public health significance. 250 76

The effect of T-2 toxin on cell-mediated resistance to bacterial infection was evaluated in mice challenge exposed with Listeria monocytogenes. Mice were treated orally on days -5, -4, -3, -2, -1, +1, and +3 with 2.0, 1.0, 0.5, or 0 mg of T-2 toxin/kg of body weight and were exposed to 10(6) (LD100) or 10(5) (LD50) L monocytogenes by intraperitoneal injection on day 0. Necrosis and depletion of lymphocytes in the thymus and spleen, decrease in thymus weight, reductions in the number of circulating total leukocytes and lymphocytes, and necrotizing gastroenteritis occurred in the toxin-treated mice. Although the cytotoxic effect of T-2 toxin on lymphoid tissue was marked, enhanced resistance to Listeria infection was revealed by significant (P less than 0.01) decreases in mortality caused by listeriosis in the toxin-treated mice. Mortality decreased from 100% to 64% in the mice exposed to 10(6) Listeria and from 50% to 20% in the mice exposed to 10(5) Listeria. Percentage of mortality after Listeria challenge exposure was dependent on the T-2 toxin dose and was progressively decreased in the mice given 0.5, 1.0, or 2.0 mg of toxin/kg.
 ...
PMID:Enhanced resistance to listeriosis induced in mice by preinoculation treatment with T-2 mycotoxin. 308 36

Listeria monocytogenes causes sepsis and meningitis in immunocompromised hosts and a devastating maternal/fetal infection in pregnant women. In recent years a more benign gastroenteritis in normal hosts has been described. Listeria has been increasingly identified as a food-borne pathogen, and large-scale contamination of processed foods with resulting outbreaks has occurred in recent years, possibly as a result of consolidation of the food industry. Experimental listeriosis in mice has proven to be an extraordinarily useful model for analyzing cell-mediated immune host defenses. Contrary to original concepts, we found that neutrophils, not macrophages, are the prime effectors during early infection. CD8+ T cells are then responsible for lysing infected hepatocytes through perforin-related (early primary and secondary infection) or Fas-L/Fas mechanism (late primary). Of interest, non-classical MHC class Ib restricted recognition mechanisms exist early, whereas MHC class Ia mechanisms can be detected throughout infection.
 ...
PMID:An updated model of cell-mediated immunity--listeriosis: clinical and research aspects. 1095 86

7 cases of listeriosis were diagnosed here between 1988-1997 (6 in last 3 years), or 2.94/100,000 admissions. 2 elderly patients suffered from meningitis and 2 pregnant women presented with premature contractions, 1 of whom delivered a premature, infected baby. 2 other patients had fever and gastroenteritis. Listeria monocytogenes was isolated from blood in 4, CSF in 2 and the placenta in 1. It was isolated from those with bacterial meningitis. All patients recovered. Both increased awareness for prevention and better diagnosis are essential to reduce morbidity from this unusual pathogen.
 ...
PMID:[Listeria monocytogenes infections--ten years' experience]. 1095 37

Listeria monocytogenes emerged as an important foodborne pathogen in the latter part of the 20th century. Clinical syndromes caused by this microorganism include sepsis in the immunocompromised patient, meningoencephalitis in infants and adults, and febrile gastroenteritis. Focal infections at other sites are less frequent. Listeria species are commonly found in raw and unprocessed food products. Major outbreaks of listeriosis, with high morbidity and mortality, have been caused by a variety of foods, including soft cheeses, delicatessen meats, and vegetable products. Improved detection methods, dietary recommendations, and, in some cases, preemptive antibiotic treatment or prophylaxis have reduced the incidence of sporadic listeriosis infections in the United States. Microbial virulence factors distinguishing environmental strains of L. monocytogenes from invasive strains causing foodborne illness and host factors promoting human infection remain incompletely understood.
 ...
PMID:Foodborne listeriosis. 1131 60

Foodborne illnesses cause a substantial human and financial burden. Despite sanitary infrastructure improvements, the incidence of foodborne bacterial infections due to non-typhoidal salmonellae (NTS), Campylobacter jejuni, and enterohemorrhagic Escherichia coli (EHEC) has risen over the last two decades. Overall, viruses account for two thirds of all foodborne illness. Most foodborne illnesses are self-limited. Supportive therapy with rehydration and the correction of electrolyte abnormalities is usually sufficient. Antibiotics play a beneficial role in the treatment of patients with certain foodborne diseases, such as listeriosis and typhoid fever, and all patients with tissue invasive or bloodstream infections. Immunocompromised patients should be treated presumptively. Antibiotics are of variable efficacy for the treatment of many infections limited to the gastrointestinal tract, and recommendations differ between pathogens. Antibiotics are generally helpful for shigellosis and cholera, and possibly beneficial for campylobacteriosis. However, antibiotics are potentially harmful in uncomplicated NTS and EHEC gastroenteritis and generally should not be used. Toxin-mediated food poisoning usually does not require specific therapy. The exception is botulism, for which botulinum antitoxin is highly efficacious if used early in the course of illness. Empiric therapy for gastroenteritis is possibly beneficial, though the magnitude of benefit is modest and incurs the risk of inadvertently treating NTS or EHEC. The choice of antibiotic should be based on local resistance patterns and the results of susceptibility testing.
 ...
PMID:Foodborne Illnesses. 1117 79

The gram-positive bacterium Listeria monocytogenes is the causative agent of listeriosis, a highly fatal opportunistic foodborne infection. Pregnant women, neonates, the elderly, and debilitated or immunocompromised patients in general are predominantly affected, although the disease can also develop in normal individuals. Clinical manifestations of invasive listeriosis are usually severe and include abortion, sepsis, and meningoencephalitis. Listeriosis can also manifest as a febrile gastroenteritis syndrome. In addition to humans, L. monocytogenes affects many vertebrate species, including birds. Listeria ivanovii, a second pathogenic species of the genus, is specific for ruminants. Our current view of the pathophysiology of listeriosis derives largely from studies with the mouse infection model. Pathogenic listeriae enter the host primarily through the intestine. The liver is thought to be their first target organ after intestinal translocation. In the liver, listeriae actively multiply until the infection is controlled by a cell-mediated immune response. This initial, subclinical step of listeriosis is thought to be common due to the frequent presence of pathogenic L. monocytogenes in food. In normal individuals, the continual exposure to listerial antigens probably contributes to the maintenance of anti-Listeria memory T cells. However, in debilitated and immunocompromised patients, the unrestricted proliferation of listeriae in the liver may result in prolonged low-level bacteremia, leading to invasion of the preferred secondary target organs (the brain and the gravid uterus) and to overt clinical disease. L. monocytogenes and L. ivanovii are facultative intracellular parasites able to survive in macrophages and to invade a variety of normally nonphagocytic cells, such as epithelial cells, hepatocytes, and endothelial cells. In all these cell types, pathogenic listeriae go through an intracellular life cycle involving early escape from the phagocytic vacuole, rapid intracytoplasmic multiplication, bacterially induced actin-based motility, and direct spread to neighboring cells, in which they reinitiate the cycle. In this way, listeriae disseminate in host tissues sheltered from the humoral arm of the immune system. Over the last 15 years, a number of virulence factors involved in key steps of this intracellular life cycle have been identified. This review describes in detail the molecular determinants of Listeria virulence and their mechanism of action and summarizes the current knowledge on the pathophysiology of listeriosis and the cell biology and host cell responses to Listeria infection. This article provides an updated perspective of the development of our understanding of Listeria pathogenesis from the first molecular genetic analyses of virulence mechanisms reported in 1985 until the start of the genomic era of Listeria research.
 ...
PMID:Listeria pathogenesis and molecular virulence determinants. 1143 15

Listeria monocytogenes, a small gram-positive bacillus, causes sepsis and meningitis in immunocompromised patients and a devastating maternal/fetal infection in pregnant women. Recent outbreaks demonstrated that L. monocytogenes can cause gastroenteritis in otherwise healthy individuals and more severe invasive disease in immunocompromised patients. Centralized processing in the food industry may be the cause of these large-scale listeriosis outbreaks. The mouse model of listeriosis, which was developed in the 1960s, has been extraordinarily useful for studying T cell-mediated immunity. Contrary to the original concept that macrophages are the principal effector cells in listeriosis, we found that immigrating neutrophils play the predominant role in early liver defenses. At later time points, CD8(+) T cells lyse infected hepatocytes by both perforin- and Fas-L/Fas--dependent mechanisms. Of interest, nonclassical major histocompatibility complex (MHC) class Ib--restricted cytolytic activity is expressed early during primary infection, whereas MHC class Ia--restricted activity is predominant through late primary and secondary infections.
 ...
PMID:Listeria monocytogenes: clinical and experimental update. 1186 36

Listeria monocytogenes is a gram-positive bacillus that causes meningitis, encephalitis, bacteremia, and febrile gastroenteritis. Most disease occurs in immunosuppressed individuals. Recent seroepidemiologic studies show that the infection is foodborne. Due to the increasing number of immunosuppressed individuals at risk for listeriosis, as well as the persistence of substantial foodborne outbreaks, L. monocytogenes has gained worldwide attention as an important pathogen. Heightened surveillance and quality control by the food industry have been instituted, leading to a reduction in the number of cases and deaths from this infection in the past decade. However, due to the ubiquity of the organism in the environment, outbreaks and sporadic disease continue to occur. The standard therapy for listeriosis is a combination of ampicillin and gentamicin or, for patients who are intolerant of b-lactam agents, trimethoprim-sulfamethazole. Despite the availability of therapy, the mortality rate remains high in those with T-cell immunodeficiencies.
 ...
PMID:Update on Listeria monocytogenes infection. 1214 74


1 2 3 4 5 6 7 Next >>