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Saudi Journal of Biological Sciences Oct 2009Blood samples from camels, sheep, goats and cattle from six Regions in Saudi Arabia were examined for blood parasites. Asir Region camels were disinfected while those of...
Blood samples from camels, sheep, goats and cattle from six Regions in Saudi Arabia were examined for blood parasites. Asir Region camels were disinfected while those of the Eastern, Jazan, Northern Frontiers, Riyadh and Tabouk Regions were infected with Trypanosoma evansi (5-40%), those of Riyadh and the Eastern Regions were infected with Dipetalonema evansi (1-6%) and those of the Eastern, Jazan and Riyadh Regions were infected with Eperythrozoon species (8-20%). Sheep and goats of all tested regions were infected with Theilaria hirci (4-20% and 6-14%, respectively), Theilaria ovis (5-19% and 6-24%, respectively) and Eperthrozoon ovis (2-9% and 2-8%, respectively). Sheep of the Eastern and Northern Frontiers Regions were also infected with Anaplasma ovis (2%) and also those of the Eastern Region were infected with Babesia motasi (4%) as well. Cattle of Asir and Eastern Regions were infected with Anaplasma marginale (1-3.4%) and those of the Eastern, Jazan and Riyadh Regions were infected with Theileria annulata (11.3-25%) and Eperthrozoon wenyoni (1-4%). Moreover, Jazan cattle were infected with Babesia bigemina (6%) and a benign Theileria species (27%). Some of these parasites are recorded in new localities indicating that they are spreading in the country. Also, this is the first report in Saudi Arabia of D. evansi in camels, A. ovis and B. motasi in sheep and A. marginale and B. bigemina in cattle. These parasites may be introduced into the country with infected livestock infested with the vectors of these parasites. The suspected vectors of the detected parasites in Saudi Arabia is discussed. Follow up surveys of blood parasites are recommended to assess their distribution and infection rates in the livestock of all Regions of Saudi Arabia, to make plans for control measures against their vectors.
PubMed: 23961044
DOI: 10.1016/j.sjbs.2009.10.002 -
The Journal of Parasitology Jun 2007We describe a new species of Dipetalonema occurring in the body cavity of Ateles chamek (Humboldt, 1812) from north-central Bolivia. Morphologic characters serving to...
We describe a new species of Dipetalonema occurring in the body cavity of Ateles chamek (Humboldt, 1812) from north-central Bolivia. Morphologic characters serving to separate Dipetalonema yatesi n. sp. from known forms include a vagina vera with a simple tube and thin walls and a left spicule, which possesses a handle shorter than the lamina (ratio 2.7); the latter displays an anterior membranous alae similar in length to the terminal flagellum, a distal extremity of the left spicule within a simple hook and a membrane, phasmids at the basis of the lappets, and heterogeneous muscles occupying the whole cavity. Dipetalonema yatesi n. sp. can be separated from Dipetalonema robini, Dipetalonema gracile, and Dipetalonema graciliformis, between other characters, in having a simple vagina vera instead of a sinuous one, and from Dipetalonema caudispina and Dipetalonema freitasi in having the lamina of the left spicule divided in a membranous alae and a terminal flagellum.
Topics: Animals; Atelinae; Bolivia; Dipetalonema; Dipetalonema Infections; Female; Male; Microscopy, Electron, Scanning; Monkey Diseases
PubMed: 17626361
DOI: 10.1645/GE-962R1.1 -
Parasite Immunology Jan 2003Filarial infections are characterized by high IgE antibody responses. So far, it is not clear whether IgE antibodies are involved in protection, pathology or both. We...
Filarial infections are characterized by high IgE antibody responses. So far, it is not clear whether IgE antibodies are involved in protection, pathology or both. We established a bioassay to detect reactive IgE antibodies in jirds infected with the filaria Acanthocheilonema viteae. Sera of A. viteae-infected jirds were used to sensitize rat basophil leukaemia (RBL) cells and degranulation was stimulated by addition of antigens of A. viteae. Reactive IgE responses were detected from 2 weeks post infection (p.i.) and throughout the A. viteae infection. Male antigen triggered the strongest mediator release, followed by female worms, infective larvae (L3) and microfilariae. Separation of male and female antigen indicated that several antigens of both genders are potent allergens. In particular, one male specific allergen of about 550 kDa induced strongest degranulation of RBL cells. In addition, mediator release stimulated by antigen fractions of about 15 kDa was due to filarial cystatin. In conclusion, we describe a convenient in vitro assay to examine IgE mediated responses in jirds. A sex specific filarial protein with high allergenic potential is identified and cystatin is established as a potent allergen of A. viteae.
Topics: Allergens; Animals; Antibodies, Helminth; Antigens, Helminth; Biological Assay; Cells, Cultured; Chromatography, High Pressure Liquid; Cystatins; Dipetalonema; Dipetalonema Infections; Female; Filariasis; Gerbillinae; Immunoglobulin E; Male; Rats
PubMed: 12753433
DOI: 10.1046/j.1365-3024.2003.00496.x -
Biophysical Journal Jan 2003ES-62, a protein secreted by filarial nematodes, parasites of vertebrates including humans, has an unusual posttranslational covalent addition of phosphorylcholine to an... (Comparative Study)
Comparative Study
ES-62, a protein secreted by filarial nematodes, parasites of vertebrates including humans, has an unusual posttranslational covalent addition of phosphorylcholine to an N-type glycan. Studies on ES-62 from the rodent parasite Acanthocheilonema viteae ascribe it a dominant role in ensuring parasite survival by modulating the host immune system. Understanding this immunomodulation at the molecular level awaits full elucidation but distinct components of ES-62 may participate: the protein contributes aminopeptidase-like activity whereas the phosphorylcholine is thought to act as a signal transducer. We have used biophysical and bioinformatics-based structure prediction methods to define a low-resolution model of ES-62. Sedimentation equilibrium showed that ES-62 is a tightly bound tetramer. The sedimentation coefficient is consistent with this oligomer and the overall molecular shape revealed by small angle x-ray scattering. A 19 A model for ES-62 was restored from the small-angle x-ray scattering data using the program DAMMIN which uses simulated annealing to find a configuration of densely packed scattering elements consistent with the experimental scattering curve. Analysis of the primary sequence with the position-specific iterated basic local alignment search tool, PSI-BLAST, identified six closely homologous proteins, five of which are peptidases, consistent with observed aminopeptidase activity in ES-62. Differences between the secondary structure content of ES-62 predicted using the consensus output from the secondary structure prediction server JPRED and measured using circular dichroism are discussed in relation to multimeric glycosylated proteins. This study represents the first attempt to understand the multifunctional properties of this important parasite-derived molecule by studying its structure.
Topics: Amino Acid Sequence; Animals; Circular Dichroism; Dipetalonema; Helminth Proteins; Models, Molecular; Molecular Sequence Data; Protein Conformation; Protein Structure, Quaternary; Protein Structure, Secondary; Protein Structure, Tertiary; Sequence Alignment; Sequence Analysis, Protein; Sequence Homology, Amino Acid; Solutions
PubMed: 12524301
DOI: 10.1016/S0006-3495(03)74868-1 -
Cadernos de Saude Publica 2001A survey on the prevalence of Dirofilaria immitis and Dipetalonema reconditum was conducted in 1,519 dogs from Maceió and two coastal areas in the State of Alagoas,...
A survey on the prevalence of Dirofilaria immitis and Dipetalonema reconditum was conducted in 1,519 dogs from Maceió and two coastal areas in the State of Alagoas, Northeast Brazil, from 1995 to 1999, by testing for microfilariae in blood. All blood samples were from exclusively domiciled dogs with a known history, showing that the infections were autochthonous, confirming transmission of canine filariasis in these areas. In Greater Metropolitan Maceió, 15 (1.3%) microfilaremic dogs were detected with D. immitis and 15 (1,3%) with D. reconditum. In the southern coastal area there was an estimated prevalence of 12.7% for D. immitis. D. immitis and D. reconditum microfilaria were 298.1 micrometer and 249.2 micrometer long and 7.3 micrometer and 4.4 micrometer wide, respectively. A Witness immunotest that detects D. immitis antigen was used to confirm parasitological results and reveal occult dirofilariasis cases. Of the total 6,579 females examined, 8 (0.1%) Culex quinquefasciatus were observed to be naturally infected with D. immitis larvae. These results proved dirofilariasis transmission in Maceió and demonstrated D. reconditum in the same geographic area.
Topics: Animals; Antigens, Helminth; Brazil; Dipetalonema; Dipetalonema Infections; Dirofilaria immitis; Dirofilariasis; Dog Diseases; Dogs; Female; Male; Prevalence
PubMed: 11784911
DOI: 10.1590/s0102-311x2001000600021 -
The British Journal of Ophthalmology Nov 2001
Topics: Anesthesia, Local; Animals; Dipetalonema; Dipetalonema Infections; Eye Infections, Parasitic; Filaricides; Humans; Male; Middle Aged; Treatment Outcome
PubMed: 11702740
DOI: 10.1136/bjo.85.11.1384i -
Memorias Do Instituto Oswaldo Cruz 1999Six hundred and eleven random-source dogs (338 male, 273 female) one year of age or older, from six sections of the city of Recife, Pernambuco, were examined antemortem...
Six hundred and eleven random-source dogs (338 male, 273 female) one year of age or older, from six sections of the city of Recife, Pernambuco, were examined antemortem for circulating microfilariae Dirofilaria immitis and Dipetalonema reconditum adult heartworm (D. immitis) antigen, and examined postmortem for adult heartworms. The prevalence of heartworm infection was 2.3% (14/611), as determined by necropsy for adult worms, and 1% (6/611) had circulating microfilariae of D. immitis; thus, 57.1% of the heartworm-infected dogs had occult infections. The results of serological testing indicated that 1.3% (8/611) of the dogs were positive for adult heartworm antigen. A total of 42 (6.9%) of the dogs had microfilariae of D. reconditum; 40 of these had only D. reconditum and two additional dogs had microfilariae of both species, D. immitis and D. reconditum.
Topics: Animals; Brazil; Dirofilaria immitis; Dirofilariasis; Dog Diseases; Dogs; Female; Male; Prevalence
PubMed: 10464398
DOI: 10.1590/s0074-02761999000500004 -
Parasite Immunology Nov 1998Filarial nematodes constitute major causes of morbidity in the Tropics. The worms have a life-span exceeding five years, a longevity which is considered to reflect at...
Filarial nematodes constitute major causes of morbidity in the Tropics. The worms have a life-span exceeding five years, a longevity which is considered to reflect at least in part, their ability to interfere with host lymphocyte responsiveness. To date the molecular mechanisms underlying this ability have not been defined but we now demonstrate that ES-62, a phosphorylcholine (PC)-containing glycoprotein released by the rodent filarial parasite Acanthocheilonema viteae, is able to render Jurkat T cells anergic to intracellular signalling via the antigen receptor (TCR). In particular, ES-62 acts by modulating activation of the tyrosine kinases Fyn, Lck and ZAP-70 leading to selective disruption of TCR coupling to the phospholipase D, protein kinase C, phosphoinositide-3-kinase and RasMAPkinase signalling cascades. These cascades are key elements in the transduction of transcriptional and proliferative signals following ligation of TCR. As PC-containing secreted products (PC-ES) are also released by human filarial parasites, our data suggest that PC-ES may play a role in the induction of T lymphocyte hyporesponsiveness observed during filarial infections.
Topics: Amino Acid Sequence; Animals; CD3 Complex; Calcium-Calmodulin-Dependent Protein Kinases; Dipetalonema; Enzyme Activation; Helminth Proteins; Humans; Inositol Phosphates; Jurkat Cells; Lymphocyte Activation; Molecular Sequence Data; Phosphatidylinositol 3-Kinases; Phospholipase D; Protein Kinase C; Protein-Tyrosine Kinases; Receptors, Antigen, T-Cell; Signal Transduction; T-Lymphocytes; ras Proteins
PubMed: 9988312
DOI: 10.1046/j.1365-3024.1998.00181.x -
The Journal of Clinical Investigation Jan 1999Intracellular bacteria have been described in several species of filarial nematodes, but their relationships with, and effects on, their nematode hosts have not...
Intracellular bacteria have been described in several species of filarial nematodes, but their relationships with, and effects on, their nematode hosts have not previously been elucidated. In this study, intracellular bacteria were observed in tissues of the rodent parasite Litomosoides sigmodontis by transmission electron microscopy and by immunohistochemistry using antiendobacterial heat shock protein-60 antisera. Molecular phylogenetic analysis of the bacterial 16S ribosomal RNA gene, isolated by PCR, showed a close relationship to the rickettsial Wolbachia endobacteria of arthropods and to other filarial intracellular bacteria. The impact of tetracycline therapy of infected rodents on L. sigmodontis development was analyzed in order to understand the role(s) these bacteria might play in filarial biology. Tetracycline therapy, when initiated with L. sigmodontis infection, eliminated the bacteria and resulted in filarial growth retardation and infertility. If initiated after microfilarial development, treatment reduced filarial fertility. Treatment with antibiotics not affecting rickettsial bacteria did not inhibit filarial development. Acanthocheilonema viteae filariae were shown to lack intracellular bacteria and to be insensitive to tetracycline. These results suggest a mutualistic interaction between the intracellular bacteria and the filarial nematode. Investigation of such a mutualism in endobacteria-containing human filariae is warranted for a potential chemotherapeutic exploitation.
Topics: Animals; Bacterial Proteins; Dipetalonema; Filariasis; Filarioidea; Immunohistochemistry; Infertility; Mice; Mice, Inbred BALB C; Microscopy, Electron; Phylogeny; RNA, Ribosomal, 16S; Rats; Rickettsia; Tetracycline
PubMed: 9884329
DOI: 10.1172/JCI4768 -
Clinical Microbiology Reviews Apr 1998Filariae of animals, especially those of mammals, often infect humans and typically produce cryptic infections. These "zoonotic" infections have been reported from... (Review)
Review
Filariae of animals, especially those of mammals, often infect humans and typically produce cryptic infections. These "zoonotic" infections have been reported from virtually all parts of the world including temperate zones. Infections may be symptomatic or not, and the parasites are found in surgical tissue biopsy specimens or, more rarely, are removed intact from superficial sites such as the orbit or conjuctivae. Typically, these worms tend to occupy tissue sites similar to those occupied in the natural animal host, with the exception of the eyes. Many kinds of filariae have been isolated from humans, including species of Dirofilaria, Brugia, Onchocerca, Dipetalonema, Loaina and Meningonema. Worms have been found in subcutaneous tissues, the heart and lungs, lymphatics, the eye, and the central nervous system. Specific identification of these filariae is based on their morphological features in histologic sections. Unfortunately, some of these worms cannot be identified even at the generic level. There are other species of filariae, presumed to be zoonotic, which produce patent infections in humans but are poorly and incompletely known. These include Microfilaria semiclarum and Microfilaria bolivarensis. It is probable that almost any filaria parasitizing animals can, under proper circumstances, infect humans and undergo some degree of development. Undoubtedly, additional species of filariae will continue to be isolated from humans in the future.
Topics: Animals; Filariasis; Filarioidea; Humans; Species Specificity; Zoonoses
PubMed: 9564568
DOI: 10.1128/CMR.11.2.366