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Biomedical subjects

O M Amin

Publications and source records attributed to O M Amin.

At least 19 recordsLinked to original sources
PubMed2000

Evaluation of a new system for the fixation, concentration, and staining of intestinal parasites in fecal specimens, with critical observations on the trichrome stain.

Proto-fix (Alpha-Tec Systems, Inc., Vancouver, WA) is a new single vial, environmentally safe, parasitology (pathogenic and nonpathogenic protozoans and helminths) fixative and transport solution. It is used in conjunction with a new concentration/sedimentation reagent, CONSED, (Alpha-Tec Systems, Inc. Vancouver, WA) as a replacement to the formalin-ethyl acetate (FEA) concentration procedure using Lugol's iodine. The newly adopted procedure was tested against the FEA concentration samples using split proficiency testing samples supplied by the American Association of Bioanalysts (AAB). Routinely, patient samples collected, fixed, and transported in Proto-Fix were processed and tested at Diagnostic Labs, Inc. (DLI), Phoenix, AZ. Detected parasites were documented using a video camera-printer system attached to the optical equipment. The quality of the fixative and stain were found to be superior to that of the FEA-Lugol's method and the yield of detected parasites was considerably higher. Eighty-five percent of 39 unknown parasite species tested were correctly detected using the Proto-fix-CONSED system compared to 46% using the FEA-Lugol's method. Of all the other methods and stains used at DLI, the trichrome stain (a popular modification of Gomori's trichrome stain for tissue sections) was found to be least reliable.

Animals↗
PubMed1995

Taxonomic notes on Polyacanthorhynchus kenyensis (Acanthocephala: Polyacanthorhynchidae) from Lake Naivasha, Kenya.

The original description of Polyacanthorhynchus kenyensis Schmidt and Canaris, 1967 from 2 species of fish in Lake Naivasha, Kenya was primarily based on measurements of 2 male cystacanths. That description is herein emended based on the availability of a larger number of immature worms of both sexes obtained from the freshwater teleosts Orechromis leucostictus, Tilapia zillii (new paratenic host records), and Micropterus salmoides. A secretory function for the apical organ is suggested.

Acanthocephala↗
PubMed1994

Acanthocephala of marine fishes off Fiji Islands, with descriptions of Filisoma longcementglandatus n. sp., Neorhadinorhynchus macrospinosus n. sp. (Cavisomidae), and gravid females of Rhadinorhynchus johnstoni (Rhadinorhynchidae); and keys to species of the genera Filisoma and Neorhadinorhynchus.

A parasitological collection from marine fishes off the Fiji Islands yielded 5 species of acanthocephalans from 4 species of fish as follows: Filisoma longcementglandatus n. sp. from scat Scatophagus argus; Neorhadinorhynchus macrospinosus n. sp. from vermiculated rabbit fish Siganus vermicularis; Neorhadinorhynchus nudum (Harada, 1938) Yamaguti, 1939 (Cavisomidae) from mackerel tuna Euthynnus affinis; Rhadinorhynchus johnstoni Golvan, 1969 (Rhadinorhynchidae) from E. affinis; and Neoechinorhynchus agilis (Rudolphi, 1819) Van Cleave, 1916 (Neoechinorhynchidae) from striped mullet Mugil cephalus. All are new locality records and, except for N. agilis, new host records. Filisoma longcementglandatus is distinguished from all other species of the genus by its very long cement glands and size and armature of its proboscis. Neorhadinorhynchus macrospinosus has distinctly larger proboscis hooks than all other members of the genus. Keys to species of the genera Filisoma and Neorhadinorhynchus are included. Gravid females of the inadequately described R. johnstoni are described for the first time. Taxonomic notes on the other acanthocephalan species are also included.

Acanthocephala↗
PubMed1993

Blood-feeding of the gerbil flea Nosopsyllus laeviceps kuzenkovi (Yagubyants), vector of plague in Inner Mongolia, China.

The gerbil flea Nosopsyllus laeviceps (Wagner) (Siphonaptera: Ceratophyllidae) is an important Palaearctic vector of enzootic plague among sylvan and campestral rodents. Laboratory blood-feeding experiments with the subspecies N.l.kuzenkovi (Yagubyants) from Inner Mongolia, China, using three rodent species including the natural host Meriones unguiculatus (Milne-Edwards), demonstrated a positive relationship between per cent feeding and time allowed for feeding, particularly for female fleas. Also the bloodmeal size was proportional to sucking time and was significantly greater in females, which are larger, than in males. However, on all four strains of host tested, there was no significant correlation between the feeding success rate of the fleas and the amount of blood they imbibed. Fleas fed better on active compared to confined M.unguiculatus. These findings agree with studies of other flea species.

Animals↗
PubMed1993

Development and longevity of Nosopsyllus laeviceps kuzenkovi (Siphonaptera) from Inner Mongolia under laboratory conditions.

The development and longevity of Nosopsyllus laeviceps kuzenkovi (Yagubyants), a major plague vector among sylvan and campestral rodents in Inner Mongolia, China, was studied under controlled laboratory conditions of 11, 14, 17, 20, 23, 26, 29, and 35 C at 76% relative humidity (R.H.), and 32, 53, 76, 87, and 100% at 23 C. Development from egg to adult was shortest (21-23 days) under favorable conditions of 26 C at 76% R.H., but maximum survival to adulthood (84%) occurred at 23 C. Average longevity was 13.25 days (13.70 in females and 12.80 in males) at 17 C and 76% R.H.; it was longer at cooler and shorter at warmer temperatures. Findings provided experimental data that helped clarify seasonal fluctuations, summer mortality, generation cycles, and survival of compared flea species from Russia, Azerbaidzhan, and China.

Animals↗
PubMed1992

Description and pathology of Neoechinorhynchus idahoensis n. sp. (Acanthocephala: Neoechinorhynchidae) in Catostomus columbianus from Idaho.

Neoechinorhynchus idahoensis is described from Catostomus columbianus caught in the Salmon River, Stanley Basin, Idaho. The new species is closest to Neoechinorhynchus venustus Lynch, 1936, but is distinguished from it by its smaller and variably structured eggs, anterio-dorsal trunk hump, bent and posteriorly notched proboscis receptacle, and larger proboscis, proboscis receptacle, and hooks. It is distinguished also from 2 other species of Neoechinorhynchus with proboscis hooks in middle and anterior circles about equally large and from 7 other species having lemnisci greatly unequal in length. Histopathology of host tissue showed limited host response exemplified by epithelial damage and hemorrhaging at point of proboscis attachment with subsequent macrophage and other phagocytic cell migration. The proboscis extended through the host epithelium into the submucosa with limited hemorrhaging at the point of attachment. Unorganized collagenous fibers were present. The lumen of the host intestine was obstructed, and compressed villi were present. The trunk of the worm damaged intestinal epithelium near the crypts, causing localized inflammation. The caryophyllaeid cestode Isoglaridacris calentinei Mackiewicz, 1974, was present in concurrent infections of C. columbianus.

Acanthocephala↗
PubMed1991

The description of Paralongicollum nemacheili n. gen., n. sp. (Acanthocephala: Pomphorhynchidae) from freshwater fishes in Kazakh S.S.R.

Paralongicollum nemacheili n. gen., n. sp. is described from Salmo gairdneri Richardson and Nemacheilus stoliczkai Steindacher in Lake Kul'say in the basin of Lake Balkhash, Kazakh S.S.R. Its long uniformly cylindrical neck and nonfiliform proboscis distinguish it from the other 3 genera of the family. Tenuiproboscis Yamaguti, 1935, has a filiform proboscis. The neck of Pomphorhynchus Monticelli, 1905, has a bulb anteriorly, and that of Longicollum Yamaguti, 1935, is spirally twisted with expansions. A key to the genera of Pomphorhynchidae is provided. The relatively longer necks in juveniles than in larger worms probably enhance the establishment of new infections. A large proportion of worms had extensive body wall deformities. Longicollum sergenti (Choquette and Gayot, 1952) Golvan, 1969, is relegated to the new genus Paralongicollum.

Acanthocephala↗
PubMed1991

Description and host relationships of Polymorphus spindlatus n. sp. (Acanthocephala: Polymorphidae) from the heron Nycticorax nycticorax in Peru.

Polymorphus spindlatus n. sp. is described from the black-crowned night heron, Nycticorax nycticorax, in Lake Titicaca, Peru. It is distinguished from all 27 known species of the subgenus Polymorphus by its spindle-shaped proboscis and its trunk shape, the anterior 2/3 of which is ovoid, tapering into a tubular posterior end. It resembles Polymorphus brevis (=Arhythmorhynchus brevis), which is, however, longer and considerably more slender, and has smaller and more numerous proboscis hooks per row and smaller eggs. It is separated also from Polymorphus swartzi, Polymorphus striatus, Polymorphus contortus, and Polymorphus cincli by its proboscis armature (usually 18 longitudinal rows of 11-13 hooks each), among other characters. Histopathological sections of host tissue show well defined localized damage including hemorrhaging with subsequent phagocyte cell migration (granular tissue). The lumen of the host intestine is obstructed and villi show compression. The proboscis of P. spindlatus extends through the intestinal mucosa and submucosa, displacing the smooth muscle layers of the muscularis externa. Fibrosis also was observed.

Acanthocephala↗
PubMed1988

Pathogenic micro-organisms and helminths in sewage products, Arabian Gulf, country of Bahrain.

Fecal and sludge samples from the Arabian Gulf country of Bahrain contained poliomyelitis and coxackie viruses, coliform bacteria, Escherichia coli, Salmonella spp., Shigella sonni, fecal streptococci, Balantidium coli, Ascaris lumbricoides and Hymenolepis nana eggs, and Strongyloides stercoralis. Sludge produced in the central sewage treatment plant is used for agricultural purposes and poses a threat to public health. Recommendations to reduce the potential health hazards are made.

Animals↗
PubMed1987

Acanthocephala from lake fishes in Wisconsin: ecology and host relationships of Pomphorhynchus bulbocolli (Pomphorhynchidae).

Pomphorhynchus bulbocolli Linkins in Van Cleave, 1919, was considerably more common in fishes of the river-connected Tichigan Lake than of the landlocked Silver Lake, southeastern Wisconsin. It is reported from 17 species of principal, accessory, and occasional definitive hosts (new record in Moxostoma carinatum) and from 13 species of paratenic hosts (new records in Amia calva, Ictalurus punctatus, Lepomis cyanellus, and Pomoxis nigromaculatus). Infection patterns were influenced by fish species, feeding behavior, temperature, availability of intermediate host, type of water body, fish movement, and changes in fish host community. Host roles are not fixed but are often interchangeable. A seasonal cycle in prevalence, intensity, and maturation was evident, with greatest abundance and maturation during summer and recruitment during summer and autumn. Recruitment of new infections, development, and release of eggs, however, occurred all year. Sex ratio changed from near equal in new infections to one more highly in favor of females in older adults. Female fish were considerably more frequently and heavily infected than males. No relationship with fish age (size) was evident. Worms were mostly attached in posterior intestinal locations but initial establishment sites correlated with temperature. Translocation of P. bulbocolli due to competitive exclusion in concurrent infections was not observed. The significance of extraintestinal larval forms in the cycle of transmission was noted.

Acanthocephala↗
PubMed1980

Fessisentis tichiganensis sp. nov. (Acanthocephala: Fessisentidae) from Wisconsin fishes, with a key to species.

Fessisentis tichiganensis sp. nov. is described on the basis of 16 male and 24 female worms recovered from 11 species of fish of seven families in Tichigan Lake, southeastern Wisconsin, between 1977 and 1979. Specimens were most frequently encountered during the spring; the only two gravid females were recovered from Umbra limi, in early June. The same fish also serves as a transport host. A key separating F. tichiganensis from the four other known species in North America is presented. The new species most closely resembles F. friedi Nickol 1972 (= F. vancleavei haley and Bullock 1953), but can be separated from it by its longer proboscis which is armed with markedly more hooks per row, among other characteristics. Additional, new morphological observations are also reported.

Acanthocephala↗
PubMed1978

Intestinal helminths of some Nile fishes near Cairo, Egypt with redescriptions of Camallanus kirandensis Baylis 1928 (Nematoda) and Bothriocephalus aegyptiacus Rysavý and Moravec 1975 (Cestoda).

Of 10 species of Nile fishes collected during the summer of 1975 at Giza near Cairo, Egypt, 7 harbored 7 helminth species. Recovered material includes 3 species of nematodes: Camallanus kirandensis Baylis 1928 (new host and geographical record), Cucullanus barbi Baylis 1923, and Rhabdochona congolensis Campana-Rouget 1961 (new host record); three species of cestodes: Khawia sp. (new in Africa), Polyonchobothrium clarias (Woodland 1925) Meggitt 1930, and Bothriocephalus aegyptiacus Rysavý and Moravec 1975; and one acanthocephalan species, Acanthosentis tilapiae Baylis 1947 (new geographical record). Morphologic observations of each species are reported. C. kirandensis and B. aegyptiacus are redescribed.

Animals↗
PubMed1975

Acanthocephalus parksidei sp. n. (Acanthocephala: Echinorhynchidae) from Wisconsin fishes.

Acanthocephalus parksidei sp. n. is described from over 4,000 specimens recovered from 11 fish hosts in the Pike River, southeastern Wisconsin. A parksidei is a highly variable acanthocephalan which appears to present an intermediate form between the only 2 other members of the same genus, A. dirus and A. jacksoni, described from North American freshwater fishes. It is structurally similar to the larger A. dirus but is separated from it primarily by having fewer proboscis hook rows and hooks per row. It is separated from A. jacksoni on the basis of its slender body form, relatively larger size of male reproductive system in proportion to body size, as well as other features. It differs from the larger European A. lucii by having smaller proboscis hooks, different hook root shape, smaller proboscis receptacle, and smaller embryos.

Acanthocephala↗
PubMed1975

Variability in Acanthocephalus parksidei Amin, 1974 (Acanthocephala: Echinorhynchidae).

Acanthocephalus parksidei Amin, 1974, was recently described from 11 species of Wisconsin fishes. Considerable variation was observed in this acanthocephalan's body size, number and arrangement of proboscis hook, size of hooks, proboscis, proboscis receptacle, lemnisci, embryos, testes, and cement glands, and number of the latter two. Most of these variations were related to worm sex and age as well as host species. Structural variations in the shape and lobation of lemnisci, abnormalities in hooks and body wall, and changes associated with monorchidism in males were noted. The significance of the erection of this new taxon in relation to the taxonomic criteria applied to acanthocephalan species is discussed.

Acanthocephala↗