PCR assay in malaria diagnosis using filter paper samples from Jazan region, Saudi Arabia

PCR assay using designed primers was evaluated in detecting human malaria infection from whole blood and/or on Whatman filter-paper compared to conventional microscopy. Two DNA extraction methods were used for dried blood-spots; QIAamp mini kit and methanol-fixation/heat-extraction. A total of 118 cases were collected from 4 hospitals at Jazan district. Microscopic examination showed positivity in 66/118 samples [56%]. Thin films showed parasitae-mia from 1+ to 4+. In PCR assay, 79 samples [70%] were positive for the genus Plasmodium given 153 base pair PCR product. All microscopy positive samples were PCR positive but PCR detected 13 cases missed by microscopy. As for filter-paper spot samples, 68 samples [57.6%] were PCR positive when DNA was extracted by QIAamp mini kit whereas 49 [41.5%] by methanol-fixation/heat-extracion method. PCR sensitivity decreased by using DNA extracted from filter-paper compared to microscopy and whole blood PCR. But the DNA isolated from filter paper detected parasites in many microscopy negative samples

Contribution of electron microscoopic studies to the biology and classification of parasitic cestodes [review article]

Members of phylum Platyhelminthes are leaf-like or tape-like worms. Class Cestoidea are exclusively parasitic organisms; covered with a nonciliated integument; ciliated epithelium, when present, confined to embryos [onchospheres] hatched from eggs; scolex provided with suckers and frequently hooks for attachment to host tissue; body in most species divided into separate, sexually complete proglottids. Class: Cestoidea: comprises two subclasses: Cestodaria body undivided; only one set of reproductive organs; oncosphere hatching from egg has 10 hooklets. Cestoda: body typically with scolex and series of proglottids,each with one set [rarely 2 sets] of male and female organs; oncosphere typically has 6 hooklets [Beaver et al., 1984]

Preliminary study of the prevalence of intestinal parasites among diarrheic inhabitants in Makkah Al Mukarramah

Diarrheic disease is one of the greatest causes of morbidity and mortality worldwide. Intestinal parasites contribute to the disease and the well being of humans. This study was undertaken in the Holly City of Makkah Al-Mukarramah. A total of 166 diarrheic stool samples were collected. A wet smear from each specimen in normal saline and Lugol's iodine solution was examined microscopically for the trophozoites and cysts of protozoan parasites. Stools were also examined using ethyl acetate formalin concentration technique to confirm the diagnosed parasites. All stool specimens were stained by Ziehl-Neelsen stain to detect the oocysts of Crypto-sporidium spp. One way ANOVA was used to analyze data. 128 persons were found to be infected, with an overall prevalence of 77.1%. 46.99% of the samples were females, and 53.01% were males. The prevalence of infection in females was 36.1%, and 40.9% in males. 16.9% of infected females were living near the Holy Masjid [down town], while 19.3% were living away from the Holy Masjid [up town]. 18.7% of infected males were living down town, while 22.3% were living up town. The majority of cases fall into the young age groups [<30 years old]. There is no significant difference between the prevalence of infection down town and up town [P=0.22], whereas the prevalence of infection between the patients over or under 30 years old was significance [P=0.036]. The rates of infection were higher in those living up town than those living down town. The results were critically discussed

Review on electron microscopy in taxonomy and biology of parasitic nemathelminthes

Electron microscopy [EM] proved a very helpful means that solved a lot of information in different scientific aspects. EM is a very good tool in the hospitals and research centers. It was aimed to pile up available information on the biology in the descriptive morphology of nematodes and their immature stages by scanning [SEM] and transmission [TEM] electron microscopy. Watson [1965a, b] studied Euchromadora vulgaris and Ascaris sp. by using TEM respectively. Lee [1969] investigated the ultra-structure of Nippostrongylus brasiliensis by SEM and TEM, as well as some nematodes by TEM [Lee, 1972]. The topography of the adult Baylisascaris procyonis caudal end was illustrated by Snyder [1989]. Male tail relatively long, smoothly attenuated, with a small button-like or mucronate termination. Pre-anal papillae situated ventrally in 2 slightly divergent and somewhat irregularly spaced rows. Anterior and posterior to anus 2 slightly raised roughened patches consisting of several rows of small spines. Just anterior to anus along outer margin of pre-anal roughened patch, a large double medio-ventral papilla. Five pairs of post-anal papillae with first pair just posterior to anus doubled and 4 pairs more closely associated in a group near tail end. Second pair with doubled papillae; but, in a few specimens fused as if 2 single closely associated papillae. Three pair single. Fourth pair of caudal papillae phasmids and in centers of each a ringed pore-like opening. Male spicules with a highly sculptured surface with a pincher-like terminal end