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Ali Khanjari Alireza Bahonar Sepideh Fallah Mahboube Bagheri Abbas Alizadeh Marjan fallah Zahra Khanjari 《亚太热带病杂志(英文版)》2014,4(2):120-124
Objective
The liver flukes, Fasciola spp. and Dicrocoelium dendriticum, infect ruminants and other mammalian extensively and cause major diseases of livestock that produce considerable economic losses.Methods
A survey of 2391 sheep and goats slaughtered at an abattoir in Amol region, northern Iran was used to determine the prevalence of the liver flukes infection based on season, sex and specie of the animals.Results
The results revealed that the prevalence rate of Fasciola spp. and Dicrocoelium dendriticum was 6.6% and 4.3% respectively. Dicrocoeliosis was more dominant in female animals (7.1%) whereas there was no sex-related difference in the prevalence of Fasciola spp. in male and female animals. Furthermore, Fasciolosis was significantly more prevalent than dicrocoeliosis in both sheep and goats. The Seasonal prevalence of Fasciola spp. was highest (P<0.005) during spring (8.3%) followed in order by autumn (8.1%), winter (5.9%) and summer (4.0%) but Dicrocoeliosis did not follow any seasonal pattern.Conclusions
According to this study, it can be concluded that Amol is regarded as an endemic region for Fasciola spp and D. dandriticum infection. Moreover, Fasciola spp. is the most widespread liver fluke found in sheep and goats which is more dominant in sheep than goats. 相似文献84.
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Mark L. Eberhard Ernesto Ruiz-Tiben Donald R. Hopkins Corey Farrell Fernand Toe Adam Weiss P. Craig Withers Jr. M. Harley Jenks Elizabeth A. Thiele James A. Cotton Zahra Hance Nancy Holroyd Vitaliano A. Cama Mahamat Ali Tahir Tchonfienet Mounda 《The American journal of tropical medicine and hygiene》2014,90(1):61-70
Dracunculiasis was rediscovered in Chad in 2010 after an apparent absence of 10 years. In April 2012 active village-based surveillance was initiated to determine where, when, and how transmission of the disease was occurring, and to implement interventions to interrupt it. The current epidemiologic pattern of the disease in Chad is unlike that seen previously in Chad or other endemic countries, i.e., no clustering of cases by village or association with a common water source, the average number of worms per person was small, and a large number of dogs were found to be infected. Molecular sequencing suggests these infections were all caused by Dracunculus medinensis. It appears that the infection in dogs is serving as the major driving force sustaining transmission in Chad, that an aberrant life cycle involving a paratenic host common to people and dogs is occurring, and that the cases in humans are sporadic and incidental. 相似文献
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PURPOSE
The aim of the present study was to assess the effect of ascorbic acid, ethanol and acetone on microtensile bond strength between fiber posts pre-treated with hydrogen peroxide and composite resin cores.MATERIALS AND METHODS
Twenty four fiber posts were pre-treated with 24% hydrogen peroxide and divided into 4 groups as follows: G1: no treatment, as control group; G2: treatment with 10% ascorbic acid solution for 5 minutes; G3: treatment with 70% ethanol solution for 5 minutes; and G4: treatment with 70% acetone solution for 5 minutes. Each fiber post was surrounded by a cylinder-shaped polyglass matrix which was subsequently filled with composite resin. Two sections from each sample were selected for microtensile test at a crosshead with speed of 0.5 mm/min. Statistical analyses were performed using one-way ANOVA and a post hoc Tukey HSD test. Fractured surfaces were observed under a stereomicroscope at ×20 magnification. The fractured surfaces of the specimens were observed and evaluated under a SEM.RESULTS
Means of microtensile bond strength values (MPa) and standard deviations in the groups were as follows: G1: 9.70±0.81; G2: 12.62±1.80; G3: 16.60±1.93; and G4: 21.24±1.95. G4 and G1 had the highest and the lowest bond strength values, respectively. A greater bond strength value was seen in G3 compared to G2. There were significant differences between all the groups (P<.001). All the failures were of the adhesive mode.CONCLUSION
Application of antioxidant agents may increase microtensile bond strength between fiber posts treated with hydrogen peroxide and composite cores. Acetone increased bond strength more than ascorbic acid and ethanol. 相似文献90.
Abbas Tavasoly Zahra Kamyabi-moghaddam Alimohammad Alizade Mohhmmadali Mohaghghi Fatemeh Amininajafi Alireza Khosravi Maryam Rezaeian Amirali Solati 《Comparative clinical pathology》2013,22(3):457-460
Fumonisin B1 is a common secondary metabolite produced by Fusarium moniliforme that occurs in corn and corn-based foods. This mycotoxin is toxic to many species of laboratory and domestic animals and is known to induce a variety of diseases such as hepatic cancer and renal and hepatic dysfunction. The structure of fumonisin B1 (FB1) resembles sphingolipids so it can inhibit synthesis of ceramide, an enzyme in the sphingolipid biosynthetic pathway. This inhibition leads to the disruption of sphingolipid metabolism and increased levels of sphinganine and sphingosine (sphingoid bases) in the serum of treated animals. It is believed that the toxicity effect of fumonisin B1 is the result of these sphingoid bases. In the present research, mice were treated with FB1 to determine its pathological effects on gastric gland and gastric mucosa in the treated mice. For this purpose, the mice were randomly assigned into two groups, namely, control (n?=?14) and treatment (n?=?15). The treatment group was fed with prepared food containing FB1 (150 mg/kg) for a period of 4 months. One day after the last treatment, all animals in both groups were euthanized and their stomach were sampled and prepared for microscopic analysis. Histopathological analysis revealed a significant decrease in parietal cell number and a significant increase in the number of inflammatory cells in gastric mucosa. Also, atrophy of gastric glands was observed. The study confirmed that FB1 poisoning can have toxicopathological effects such as gastric gland atrophy and gastritis on mice gastric tissue. 相似文献