Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019158 (hepatitis)
 30,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Synergy between exposure to chemical carcinogens (nitrosamines) and infestation with the liver fluke Opisthorchis viverrini has been demonstrated in a hamster model of hepatocarcinogenesis (Flavell et al., Carcinogenesis 4:927-930, 1983; Thamavit et al., Carcinogenesis 8:1351-1353, 1987). To elucidate the mechanisms of this interaction we tested the hypothesis that liver parasitism might influence the expression and activity of carcinogen metabolizing enzymes. We found that one, and perhaps more, hamster liver cytochrome P450 (CYP) isozymes immunorelated to mouse CYP2A5 contributed up to 50 or 60% of the hepatic aflatoxin B1 (AFB) and N-nitrosodiethylamine (NDEA) metabolism, respectively. As inferred from average enzyme activities and from western blot, immunoinhibition, and substrate (coumarin) inhibition analyses, O. viverrini infestation increased the expression of enzymes detectable by anti-CYP2A5 antibody as well as NDEA metabolism in male but not in female hamsters. Immunohistochemical analysis of CYP2A expression by anti-mouse CYP2A5 antibody demonstrated that the O. viverrini-associated increase was not uniformly distributed throughout the liver but occurred in hepatocytes immediately adjacent to areas of inflammation. Immunohistochemical analysis of AFB-DNA adducts in the livers of O. viverrini-infested hamsters treated with AFB showed that the highest levels of adducts were found in the regions of liver where hepatocellular expression of enzymes detectable by anti-CYP2A5 antibody is induced. These results suggest that a high local expression of CYP isozymes in O. viverrini-infested livers could be a contributing risk factor in the development of liver cancers associated with parasitic hepatitis.
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PMID:Association of liver fluke (Opisthorchis viverrini) infestation with increased expression of cytochrome P450 and carcinogen metabolism in male hamster liver. 791 96

The authors present marsh rat Holochilus brasiliensis, jirds Meriones shawi and M. unguiculatus as new models of Schistosoma haematobium infection. Histological findings were compared with those of classic models mouse Mus and hamster Mesocricetus. In new models, embryonated eggs were seen in the stool from 90 days post infestation (DPI) and active disease developed from 117 to 175 DPI. Seven out of 10 rodents presented granulomatous and/or chronic cystitis, fibrosis, polyps and urothelial changes: squamous metaplasia, precancerous dysplasia and squamous cell carcinoma of the urinary bladder. In the digestive tract of all new models, granulomas eroded the mucosa, formed inflammatory polyps, infiltrated the wall and accumulated into bilharziomas. In the liver, granulomatous hepatitis surrounded by bilharzial pigment deposit was apparent. Pipe-stem fibrosis involved 4 rodents with precirrhotic changes in 1 and portal hypertension in 2. One female Meriones suffered from granulomatous endometritis and salpingitis. All new models developed pulmonary granulomatosis with associated vascular lesions: giant cell arteritis in 1 rodent, thromboses in 3 and pulmonary hypertension in 4 others. In classic models, 1 Mus presented a squamous cell carcinoma of the urinary bladder while Mesocricetus displayed diverse lesions in digestive and genital tracts, liver and lungs. All tissue lesions, resembling those seen in humans in all points, were far more frequent and severe in new models than in classic ones. Those involving the urinary bladder have never been reported in other models such as monkeys: Pan troglodytes, Cercopithecus aethiops and Cebus apella. A comparison was carried out between different models on the basis of experimental conditions: definitive hosts, number of cercariae used, type and duration of infection. This study clearly demonstrated that Holochilus brasiliensis, Meriones shawi and M. unguiculatus are perfectly adequate models in terms of laboratory facilities. They are helpful in investigating the pathogenic mechanism of some disorders in S. haematobium infection, particularly tumours of the urinary bladder, and this may enhance therapeutic assays.
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PMID:Histopathological observations in new and classic models of experimental Schistosoma haematobium infections. 867 38

Chronic disease conditions that are associated with elevated proliferation are well established as risk factors for cancer development. These may be due to viruses (for example, in the case of hepatitis and liver cancer), bacterial infections, parasite infestation or physical trauma. In addition to these exogenous agents there are also metabolic abnormalities that can contribute, caused by genetic or epigenetic influence. In the latter case, an increase in serum levels of the hormones oestrogen, testosterone and insulin may be of special importance. The present review concentrates attention on factors that induce elevated cell turnover and for which there is epidemiological and/or experimental evidence of a link with neoplasia, with particular stress on the individual organ or tissue level.
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PMID:Chronically elevated proliferation as a risk factor for neoplasia. 988 83

We investigated the prevalence of peripheral blood abnormalities, parasitic infestation, and hepatitis virus infection, by using the results of the primary screening health checkups for 423 students (male: 317, female: 106, average age +/- SD: 34.2 +/- 5.5 year-old) from abroad. Most of them were from Southeast Asia, Africa, Central and South America, and other developing countries in tropical or subtropical areas. Thalassemia-like hematological disorders, showing microcytic peripheral red blood cells without any anemia, were seen in 7.6 percent of the students, and intestinal parasites were revealed in 12.7 percent of them. The positive rate for anti-hepatitis A virus antibodies (84.3%) and the exposure rate of hepatitis B viruses (35.3%) were similar to previous reports. Compared with the positive rate for anti-hepatitis C virus antibodies (anti-HCVAb) of students from other regions (1.5%), a significantly high seropositivity for anti-HCVAb was encountered in Egyptian participants (21.1%). In recent years, population shifts and rapid transportation have facilitated the spread of certain infectious diseases from endemic to non-endemic areas. International preventive strategies, education of people regarding infectious diseases, and sufficient medical staffs for this purpose are urgently recommended.
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PMID:[Implication of health checkups of students from developing countries in Japan]. 1051 90

We have investigated several groups of Thai patients diagnosed with chronic liver disease including chronic hepatitis, cirrhosis and hepatocellular carcinoma, as well as cholangiocarcinoma, for the prevalence of infection with either one of the hepatitis viruses B, C, G and the novel hepatitis virus TT (TTV). The 168 patients tested comprised 120 men and 48 women with their median age ranging from 42.3 to 62.3 years. Screening for antibodies to HBV and HCV was performed by a commercially available serological test kit, for the presence of HBV and TTV DNA by PCR, and of HCV and HGV RNA by RT-PCR, respectively. There was a clear two-fold higher prevalence of HBV (49%) over HCV (27%) infection and a four-fold higher frequency compared to HGV (13%) and TTV (11%) infection, respectively, in those individuals with chronic hepatitis, cirrhosis, and hepatocellular carcinoma, whereas all but one patient with cholangiocarcinoma the etiology of which has been ascribed to parasitic infestation, were free of all viral markers. In Thailand chronic HBV, and to a lesser extent, chronic HCV infection represent the two most common causes of hepatitis potentially proceeding to chronic liver disease, whereas the clinical significance pertinent to HGV and TTV remains to be elucidated.
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PMID:Hepatitis viruses and chronic liver disease. 1077 57

Cholangiocarcinoma occurs with a varying frequency in different areas of the world. Some of the variations in incidence rates can be explained by the distribution of risk factors in different geographic regions and ethnic groups. Several accepted risk factors for cholangiocarcinoma include infestation with liver flukes, primary sclerosing cholangitis, hepatolithiasis, choledochal cysts, cirrhosis, and infusion of certain chemical agents. Approximately, 90% of patients diagnosed with cholangiocarcinoma do not have a recognized risk factor for the malignancy. The study by Ahrens et al. [16] finds that obesity and gallstones are risk factors for developing extrahepatic cholangiocarcinoma in men patients. Obesity was found to have a 'dose-effect' relationship with the strength of statistical association. No significant association was reported for tobacco or alcohol use, hepatitis, cirrhosis, diabetes, or inflammatory bowel disease. Although the author's definition of extrahepatic cholangiocarcinoma was unusual, the association of obesity with the risk of developing cholangiocarcinoma persisted for all anatomic subsites.
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PMID:Risk factors for cholangiocarcinoma. 1762 30

The present study describes a subclinical necrotizing granulomatous hepatitis in normal broilers routinely slaughtered in a medium-sized (72,000 birds per day) abattoir in the Netherlands. An exploratory investigation was scheduled on line during 20-min periods for 82 flocks (3000 birds examined per period). Liver and duodenum samples were collected for histopathology from 365 birds with liver pathology. Bacteriology was performed from 240 livers with lesions and 80 control livers. In addition to the hepatic pathology, other gross lesions of the carcasses, such as footpad dermatitis and broken legs/wings, were noted. The average prevalence for gross liver lesions was 0.16% (ranging from 0% to 0.63% per flock); 89.59% of the livers were enlarged, had a firm consistency, and revealed multifocal necrotic spots. Microscopically, 51.66% showed a granulomatous reaction in addition to the necrosis. There was no consistent anaerobic or aerobic bacterial growth in comparison to normal livers. A large proportion of the livers revealed growth of Escherichia coli, Bacteroides spp., Lactobacillus spp., Staphylococcus spp., and Streptococcus spp., and this was often with more than one type of bacterial colony. The duodenum mucosa grossly showed some redness with a mucous mass on its surface. Microscopically (n = 176) in 5.70% there were no changes in anatomy and cellular activities; 64.20% had a mildly increased number of lymphoid cells and heterophils in the lamina propria and between villus epithelial cells. The remaining 30.10% had moderate degenerative changes of villus epithelium with a mixed cellular infiltration in the lamina propria; 23.29% of the duodenum samples contained coccidia (infestation stage: mild to moderate). Signs of overgrowth with Clostridium spp. were not observed. There was a small, but significant correlation (rs = 0.30; P = 0.006) between prevalence of liver pathology and footpad dermatitis.
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PMID:Necrotizing granulomatous hepatitis in slaughtered broilers. 1762 99

Cimex lectularius (the "bedbug") is an insect that feeds nocturnally, taking a requisite blood meal from a sleeping human or other parasitized host. Immunological reactions to bedbug saliva vary, but typically, bites yield erythematous and pruritic papules. The face and distal extremities, areas uncovered by sleeping clothes or blankets, are preferentially involved. Until the late 1990s, bedbug infestations in the United States were declining. Resurgence is attributed to increased travel and resistance to insecticides. Although hepatitis or human immunodeficiency virus is not effectively transmitted by the bedbug, pruritus and the fear and perceived violation of an infestation can be debilitating. Bedbugs are small but robust, and their ability to remain ensconced in crevices within the bedroom makes eradication difficult. As more patients present with bedbug bites, physicians must possess the knowledge to diagnose, treat, and educate with regard to bedbug bites and bedbug infestations.
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PMID:Bedbugs. 1958 May 78

Cholangiocarcinoma (CCA), a cancer originating from the neoplastic transformation of the biliary epithelium, is characterized by a progressive increase in incidence and prevalence. A number of risk factors have been identified including primary sclerosing cholangitis, liver fluke infestation, and hepatolithiasis. More recently, hepatitis viruses (HCV, HBV) have been taken into consideration as risk factors for the intrahepatic CCA and this could explain the increased incidence seen in the last two decades. All these risk factors induce chronic inflammation in the biliary epithelium together with partial bile obstruction. These two conditions are considered the background (chronic inflammation) favouring the cancer development. The only effective treatment is the radical surgical resection but, this is applicable in less than 40% of the patients since CCA is mostly diagnosed at an advanced stage. This mainly occurs because, in the majority of the cases, CCA is clinically silent, with symptoms only developing at an advanced stage but also for the lack of effective biomarkers to be used for a screening purpose. A number of serum and bile biomarkers have been recently proposed for the diagnosis of CCA but, their impact on the early diagnosis is still under the evaluation.
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PMID:Cholangiocarcinoma: risk factors and clinical presentation. 2049 49

A field survey was conducted to evaluate the prevalence of bacterial infections among free-living White Ibis (Nipponia nippon) in which 92 bacterial isolates were recovered from 193 different internal organs of 55 apparently healthy Ibis. Escherichia coli and Salmonella spp. were isolated at rates of 43.6% and 14.5%, respectively. The other bacterial pathogens isolated were Shigella spp. (34.5%), Enterobacter spp. (21.8%) Citrobacter spp. (18.1%), Klebsiella pneumonia (16.3), Staphylococcus aureus (10.9%) and Proteus mirabilis (7.2%). The antibiogram indicated that all isolates were highly sensitive to ciprofloxacin, enrofloxacin, trimethoprim and penicillin. Penicillin was most effective against S. aureus. An examination of the gastrointestinal tract revealed the presence of a nematode, Ascaris (Porroceacum ensicaudatum), and three trematodes (Echinochasmus perfoliatus, Apatemon aracilis and Patagifer bilobus). Other trematodes were detected in enlarged gall bladder and kidney lesions. Histopathological examination showed signs of hepatitis. The gall bladder had cholangitis, cholicystitis which may have been caused by trematode infestation. The kidneys also showed multiple parasitic cysts of trematodes and non-suppurative interstitial nephritis. This study suggests the possible role of the White Ibis, when living near poultry populations, in transmitting certain pathogens to poultry.
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PMID:Prevalence of bacteria and parasites in White Ibis in Egypt. 2085 78


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