DNA differential diagnosis of human taeniid cestodes by base excision sequence scanning thymine-base reader analysis with mitochondrial genes.
(1/21)
For DNA differential diagnosis of human Taenia cestodes, a base excision sequence scanning thymine-base method using the cytochrome c oxidase subunit I and cytochrome b genes as targets was used. The characteristic thymine-base peak profiles provide four distinct types, unique for T. saginata, T. asiatica, and two genotypes of T. solium. This approach provides a useful tool for the identification and diagnosis of human taeniid cestodes without DNA sequencing if nucleotide sequence databases are available. (+info)
The use of urban sewage sludge on pastures: the cysticercosis threat.
(2/21)
Urban sewage production is increasing and its agronomical use as a fertiliser has been advocated. Considerable defiance is prevalent in consumers and among farmers on the use of such fertilisers due to unknown pathological or environmental risks. The aim of the present review was to consider which pathological risk is major. Cysticercosis due to Taenia saginata appears to be one of the major pathological threats when sewage sludge is used to fertilise cattle pastures in temperate areas. The situation is different in Africa (Taenia solium and T. saginata are both highly prevalent) and Asia (Taeniasaginata-like are prevalent). The processing of sludge and the delay between its application onto a pasture and grazing are probably major risk factors. Little data are available on the influence of processing, delay between processing and the use of sludge on the pathogenic risk. Producers and consumers will be more confident on the use of sludge if objective data are gained on risk. Most of the cases of cysticercosis (North America, United-Kingdom, Germany or Denmark) are related to poor human hygiene or accidental overflooding of sewage plants onto pastures. The standard application of sludge on pastures is apparently at low risk. This low risk does not mean that surveillance should cease since outbreaks of cysticercosis have been reported. Future investigations should concentrate on the most sustainable means of reducing risk (length of storage before use, composting, other treatments). (+info)
Control of Taenia saginata by post-mortem examination of carcasses.
(3/21)
BACKGROUND: A study to curb transmission cycle of a zoonotic Taenia cestodiasis between humans and cattle is presented. OBJECTIVE: To evaluate the reliability of meat inspection procedure in detecting carcasses of cattle with T. saginata cysticercosis. METHODS: A total of 55 cattle divided into two groups of artificially (n=30) and naturally (n= 25) infested animals were utilized. Total dissection method was used as a gold standard of validity. RESULTS: Meat inspection insensitively revealed cysticerci in 12 carcasses in each group compared with 24 and 23 carcasses revealed by total dissection in natural and artificial infestations, respectively. Sites of oncosphere invasion showed great variations with the two groups of cattle. In the predilection sites, most cysticerci were found in the heart, Triceps brachii, tongue and head muscles in that order. However, non-predilection sites (neck and back, hind limbs, chest, pelvic and lumbar regions, lungs and liver) considerably harboured high numbers of cysticerci. Observations indicated that except for the dead, degenerate or calcified cysticerci a careless meat inspector will most likely miss out quite a number of viable cysticerci, which blend the pinkish-red colour of the meat and be passed on for human consumption, becoming the source of bovine cysticercosis. CONCLUSIONS: The results confirmed that in spite of the time and efforts taken by meat inspectors looking for cysticerci at specified predilection sites of carcasses, this method is insensitive and inaccurate. To effectively improve meat inspection procedures, there is need to increase the area and number of predilection sites observed during inspection and vary them according to the nature of the animals, their husbandry history and the target human population for consumption. In addition, other control approaches such as vaccination, chemotherapy and immunodiagnosis should be developed and implemented to complement meat inspection procedures. (+info)
Application of synthetic peptides to the diagnosis of neurocysticercosis.
(4/21)
We tested the possible diagnostic utility of five Taenia saginata oncosphere-derived synthetic peptides in T. solium neurocysticercosis (NC). The five peptides correspond to protein sequences with high antigenic indexes that were cloned from a T. saginata oncosphere cDNA library. The test samples consisted of cerebrospinal fluid (CSF) samples randomly collected from patients referred from Mexican and Brazilian neurological institutes. Indirect enzyme-linked immunosorbent assays (ELISA) were carried out with the peptides either unconjugated or coupled to carrier proteins, and were compared with results obtained using T. solium cyst fluid as a positive control. For active inflammatory NC, the higher sensibility (93%) and specificity (85%) was obtained with peptides HP6-2 and Ts45W-1, respectively, coupled to ovalbumin, in both Mexican and Brazilian patients. Examining the results of the individual peptide assays in combination, in some instances, improved the sensitivity to 100%. (+info)
Diagnosis of taenia saginata cysticercosis by immunohistochemical test on formalin-fixed and paraffin-embedded bovine lesions.
(5/21)
A new method of diagnosing cysticercus or larval stage of the human tapeworm, Taenia saginata, also known as Cysticercus bovis, in formalin-fixed bovine tissue was developed using a monoclonal antibody to T. saginata and avidin-biotin complex immunohistochemistry. Grossly recognizable viable and degenerate cysts were identifiable after immunohistochemical staining and could be differentiated from Sarcocystis, Actinobacillus, or non-cyst, normal bovine structures. Thenew test should permit laboratory confirmation of suspected T. saginata cysticercus lesions. (+info)
Recovery of putative taeniid eggs from silt in water associated with an outbreak of bovine cysticercosis.
(6/21)
Degenerate taeniid-like eggs consistent with Taenia saginata were recovered from sediment in the water supply of a beef feedlot under quarantine for Cysticercus bovis. Nine degenerate eggs in total were recovered from 482 modified flotation assays. Flotation controls of sediment spiked with known numbers of T. saginata eggs had poor egg recoveries, supporting the need for more sensitive assays for environmental samples. (+info)
Bovine cysticercosis: preliminary observations on the immunohistochemical detection of Taenia saginata antigens in lymph nodes of an experimentally infected calf.
(7/21)
A newly developed immunohistochemical test was used for the first time to demonstrate the presence of Taenia saginata (Cysticercus bovis) antigens in the lymph nodes of a heifer calf experimentally inoculated with Taenia saginata eggs. The new test should aid in the differential diagnosis of eosinophilic lymphadenitis in cattle. (+info)
Fecal specimens preparation methods for PCR diagnosis of human taeniosis.
(8/21)
Sample preparation and DNA extraction protocols for DNA amplification by PCR, which can be applied in human fecal samples for taeniasis diagnosis, are described. DNA extracted from fecal specimens with phenol/chloroform/isoamilic alcohol and DNAzol reagent had to be first purified to generate fragments of 170 pb and 600 pb by HDP2-PCR. This purification step was not necessary with the use of QIAmp DNA stool mini kit. Best DNA extraction results were achieved after eggs disruption with glass beads, either with phenol/chloroform/isoamilic alcohol, DNAzol reagent or QIAmp DNA stool mini kit. (+info)