A new species of Acanthobothrium van Beneden, 1849 (Eucestoda:Tetraphyllidea: Onchobothriidae) in Dasyatis longus Garman (Chondrichthyes:Myliobatiformes:Dasyatididae) from Chamela Bay, Jalisco, Mexico

A new species of Acanthobothrium in Dasyatis longus from Chamela Bay, Jalisco, Mexico, is a member of a presumed clade of species diagnosed by being anapolytic or nearly so, having more than 100 testes per proglottis, with immature and mature proglottides wider than long to square, aspinose scolex, muscular bothridia fused to the scolex at their posterior ends, H- to V -shaped ovaries, relatively short symmetrical to asymmetrical ovarian arms that extend anteriorly to, or nearly to, the cirrus sac, and vitellaria arranged in fields rather than a single row of follicles. The new species most closely resembles Acanthobothrium terezae from the freshwater stingray Potamotrygon motoro in the following characters: bothridial hooks longer than 200 microns with inner hooks having bent asymmetrical prongs, an average of 130-140 testes per proglottis, and shallow genital atria located posterior to midline of proglottis. The new species differs from A. terezae by having outer hooks approximately the same size and shape as the inner hooks, inner hooks averaging 230 microns rather than 313 microns in total length, and cirrus sacs averaging 255 microns rather than 450 microns in length. The new species is unique among all described species of Acanthobothrium by having a cleft in the posterior margin of each apical bothridial pad. The apparent close relationship of the new species to one inhabiting a Neotropical freshwater stingray provides support for the hypothesized Pacific marine ancestry of Neotropical freshwater stingrays and raises the possibility that the Neotropical freshwater stingrays may not be monophyletic.     

Two new species of tetraphyllidean cestodes in Himantura pacifica (Chondrichthyes: Myliobatiformes: Dasyatididae) from the northwest coast of Costa Rica

The tetrapeptide AcSer-Asp-Lys-Pro (AcSDKP) is a physiological negative regulator of hematopoiesis in mammals. It acts by blocking the cell cycle entry of quiescent stem cells and progenitors. In the present study we report that AcSDKP blocks the proliferation of human as well as chicken lymphocytes. It inhibits by 25 to 40% the polyclonal mitogen- (phytohemagglutinin (PHA), pokeweed mitogen (PWM), or concanavalin A) or mixed lymphocyte reaction-induced proliferation of chicken lymphocytes. A comparable degree of inhibition was observed in human whole blood cultures stimulated by "T" (PHA) or "T and B" (PWM) mitogens. Our results obtained on two phylogenetically distant species show that AcSDKP reduces the lymphocyte proliferation probably by blocking or retarding entry into the cell cycle as previously demonstrated for hematopoietic progenitors and hepatocytes. Therefore, this endogenous, non-species-specific tetrapeptide may be involved in the regulation of immune response.     

Two new species of Acanthobothrium in Narcine entemedor (Rajiformes: Narcinidae) from the northwest coast of Guanacaste Peninsula, Costa Rica

This paper describes 2 new species of Acanthobothrium collected in Narcine entemedor from Cuajiniquil, Guanacaste Province, Costa Rica (10 degrees 57'N, 85 degrees 42'W). Acanthobothrium franus n. sp. averages 27 mm long, composed of 110 proglottides, has bothridial hooks 344-469 microns long, and 24-56 testes per proglottis. This new species resembles Acanthobothrium colombianum, Acanthobothrium coquimbensis. Acanthobothrium dujardini, Acanthobothrium lineatum, Acanthobothrium lintoni, and Acanthobothrium paulum. The new species differs from these 6 species by having a relatively shorter cirrus sac length not reaching the middle region of the proglottis. Additionally, A. franus differs from these species by having longer bothridia (627-1,408 microns vs. 299-391 microns for A. colombianum, 312-480 microns for A. coquimbensis, 240-560 microns for A. dujardini, 275-624 microns for A. lineatum, 389-720 microns for A. lintoni, and 300-880 microns for A. paulum), and larger bothridial hooks (344-469 microns vs. 175-193 microns, 120-192 microns, 180-210 microns, 118-216 microns, 108-230 microns, and 104-229 microns, respectively). Acanthobothrium inbiorium n. sp. averages 59 mm long, composed of 198 proglottides, has bothridial hooks 95-120 microns long, and possesses 44-73 testes per proglottis. Among species of Acanthobothrium, the new species resembles Acanthobothrium electricolum, Acanthobothrium dasybati, Acanthobothrium dighaensis, Acanthobothrium icelandicum, Acanthobothrium indicum, Acanthobothrium microcephalum, and Acanthobothrium wedli. The new species closely, resembles A. dasybati, but differs from that species in average strobila length and number of proglottides (58 microns long and 198 proglottides in A. inbiorium vs. 20 and 80 in A. dasybati, respectively). The new species can be distinguished from A. electricolum by having a wider scolex (450-900 microns vs. 189-252 microns), from A. dighaensis by having a narrower scolex (450-900 vs. 1,050-1,429), and from A. indicum by average strobilar length and number of proglottides (58 mm and 198 for A. inbiorium vs. 25 mm and 145 for A. indicum). Finally, A. inbiorium differs from A. icelandicum by having a shorter cirrus sac (122-285 for A. inbiorium vs. 380-410 for A. icelandicum), and A. microcephalum and A. wedli by having longer bothridia (an average of 603 microns vs. 447 microns for A. microcephalum and 350 microns for A. wedli), and fewer testes per proglottis (44-73 vs. 105-115 and 80-100, respectively). Morphological similarities suggest that some components of the eastern Pacific fauna of Acanthobothrium might share historical associations with the Caribbean and the western Pacific/Indian Ocean fauna.     

Sokoloviana kucheruki sp. n. from the killdeer from Cuba (Analgoidea, Pterolichidae)

Wistar rats consumed a liquid diet containing sustagen and ethanol for a period of 150 days. Control animals were pair-fed an identical diet except for isocaloric substitution of sucrose for ethanol. Forty-five days after the liquid diets were discontinued both groups were tested for performance on the Hebb-Williams maze. The experimental group made significantly more errors than the control group indicating that long-term ingestion of alcohol can lead to substantial impairment of problem-solving abilities in rats.     

Infectious agents associated with diarrhoea of calves in the canton of Tilarán, Costa Rica

A case-control study of calves under 3 months of age was carried out by weekly visits to 15 farms in the canton of Tilarán, Costa Rica. Most farms were dedicated to beef or dual-purpose (DP) production. Faecal samples were collected over a 6-month period from a total of 194 calves with clinical signs and from 186 animals without clinical signs of diarrhoea as assessed by a scoring system. The samples were investigated for the presence of viruses, bacteria and parasites. Torovirus was detected for the first time in Costa Rica and was present in 14% of calves with diarrhoea and in 6% of the controls. Coronavirus and Rotavirus were less frequently encountered in either one of the groups (in 9 and 7% of scouring calves and in 1 and 2% of controls, respectively). Escherichia coli was detected in 94% of all the faecal samples, but isolates from only three samples from calves with diarrhoea contained the K99 antigen. Similarly, Salmonella was found only in scouring calves. Cryptosporidium oocysts were detected in animals with signs of diarrhoea, while other coccidia oocysts, Strongylida and Strongyloides eggs were frequently found in animals both with and without diarrhoea. A conditional logistic regression (CLR) analysis to compare healthy and scouring calves showed a significant difference with regard to the presence of Torovirus, Rotavirus and Coronavirus.     

Ascocotyle (A.) nunezae n. sp. (Digenea: Heterophyidae) from Yucatan, Mexico

Inoculation of soil with bacteria (a Gram-negative rod [PD2] and a 4-membered consortium [DC1]) accelerated mineralisation of phenanthrene and pyrene (but not naphthalene) added individually to a pristine sand and a pristine organic soil. The half-life of naphthalene was 3.5 days in both soils whether inoculated or non-inoculated. However, the half-life of phenanthrene decreased from 86 days in non-inoculated sand soil and 80 days in the non-inoculated organic soil to 3.6 days in the sand and 3.1 days in organic soil when inoculated with PD2, and to 6.6 days in the sand and 8.7 days in the organic soil when inoculated with DC1. Phenanthrene mineralisation ceased after 23 days in DC1-inoculated soil and was 71.3 +/- 3.6% (sand) and 63.3 +/- 2.8% (organic). This compared with 96.8 +/- 3.8% (sand) 102.8 +/- 2.5% (organic) after 8 days in PD2-inoculated soil. Inoculation with DC1 (but not PD2) also accelerated mineralisation of pyrene, where the half-life decreased from 155 days to 18 days in the sand soil, and from 216 days to 33 days in organic soil.     

Heavy metals in the hair of opossum from Palo Verde, Costa Rica

Levels of lead, cadmium, mercury, chromium, and manganese were measured in the hair of opossum (Didelphis virginiana) from Palo Verde, Guanacaste, Costa Rica. This area has some agriculture, but is slated for extensive water development that will increase ecosystem exposure to a variety of agricultural chemicals. Metal levels were generally not intercorrelated except for chromium and lead, chromium and cadmium, and cadmium and lead. There were significant gender differences only for lead and chromium, with the significantly smaller females having higher levels. It is suggested that hair from mammals, particularly abundant ominivores may be useful, bioindicators of environmental quality over a long time period.     

Cercopithifilaria shohoi n. sp. (Nematoda: Filarioidea) from the relict Bovidae, Capricornis crispus, in Japan

Thirty-five chordomas and more than 100 other tumors that have to be considered in the differential diagnosis, were immunohistochemically analyzed using a panel of antibodies including those to subsets of keratins (K), HBME-1, a monoclonal antibody recognizing an unknown antigen on mesothelial cells, and neuroendocrine markers. The patterns of immunoreactivities in chordoma were compared with those in renal cell carcinoma, colorectal mucinous adenocarcinoma, pituitary adenoma, skeletal chondrosarcoma, and extraskeletal myxoid chondrosarcoma (ESMC). Chordomas were consistently positive for keratin cocktail AE1/AE3, and for the individual keratins K8 and K19, and nearly always positive for K5, but they showed negative or only sporadic reactivity for K7 and K20. The keratin K8 and K19 reactivity was retained in those chordomas showing solid sheets of epithelioid, spindle cells, or cartilaginous metaplasia, and in one of two cases showing overtly sarcomatous transformation. In comparison, keratins were never present in skeletal chondrosarcoma, although K8 and to a lesser extent K19 were seen in occasional cases of ESMC with chordoid features. HBME-1 reacted strongly with chordoma and skeletal chondrosarcoma but was almost never positive in renal or colorectal carcinoma. These carcinomas lacked K5-reactivity, in contrast to chordoma. Chordomas were also consistently positive for neuron-specific enolase and occasionally focally for synaptophysin, but never for chromogranin. In contrast, pituitary adenomas regularly expressed the full spectrum of neuroendocrine markers and differed from chordoma by having a narrower repertoire of keratins, often showing negative or focal keratin 8- or AE1/AE3 reactivity and being almost always K19-negative. These findings indicate that chordoma can be immunohistochemically separated from tumors that can resemble it. Immunohistochemistry is especially useful in the diagnosis of small biopsy specimens that offer limited material for morphological observation.     

Lissorchis macropharynx n. sp. (Digenea: Lissorchiidae) from the shorthead redhorse, Moxostoma macrolepidotum (LeSueur) (Osteichthyes: Catostomidae)

Lissorchis macropharynx (Digenea: Lissorchiidae) is described from the shorthead redhorse, Moxostoma macrolepidotum (LeSueur) (Catostomidae) from the Assiniboine River drainage of southern Manitoba. The species is morphologically similar to Lissorchis hypentelii in possessing a similar body shape (widest at the ovarian region and a relatively long hindbody), a distinctly trilobed and relatively posteriorly situated ovary, and in the distribution of the vitellaria. It differs from L. hypentelii and all other lissorchiids in possessing a massive pharynx that is generally equal in length to or longer than the oral sucker and almost as deep as the cervical region of the body it occupies, a protruding acetabular region with an aspinose ridged/folded and grooved anterior surface, and a massive cirrus sac that reaches the level of the ovary. Museum specimens of Lissorchis spp. from M. macrolepidotum from other drainages in Manitoba and Wisconsin were also identified as L. macropharynx.     

Spauligodon gehyrae n. sp. (Nematoda:Pharyngodonidae) from Gehyra oceanica (Sauria:Gekkonidae) from Guam, Mariana Islands, Micronesia

Spauligodon gehyrae n. sp. (Nematoda: Pharyngodonidae), a new oxyurid nematode, discovered in the large intestine of the gecko Gehyra oceanica is described and illustrated. Nine of 11 adult female specimens of G. oceanica collected on Guam, Mariana Islands, Micronesia, harbored a total of 480 specimens of S. gehyrae; prevalence of infection was 82% (mean intensity 53, range 6-179). Spauligodon gehyrae represents the 33rd species to be described for this genus and is distinguished by the presence of truncated egg ends, the short stiff tail spike of the female, and the presence of a spicule in the male. This is the second species of Spauligodon to be described from Oceania.     

Eucyathostomum webbi sp. n. (Strongyloidea: Cloacinidae) from white-tailed deer (Odocoileus virginianus)

The new species is described from white-tailed deer of McIntosh County, Georgia, and Pushmataha County, Oklahoma. Eucyathostomum webbi sp. n. differs from E. longesubulatum (type) in possessing more internal leaf crown elements, unbarbed spiculte tips, variability in the configuration of the dorsal ray of the male bursa, and shorter vagina and ovejectors; from E. copulatum in being much larger and not having males and females permanently united; from E. spinulosum in the origin of the externo-dorsal ray of the male bursa; and from E. dentatum in having more internal leaf crown elements, shorter spicules, a distinct cephalic vesicle, no dorsal gutter, and a pectinated flange posterior to the vulva. Problems in the taxonomy of the genus Eucyathostomum are discussed. Specimens previously identified as E. longesubulatum from southeastern white-tailed deer were reexamined and found to be conspecific with E. webbi.     

Sarcocystis buffalonis n.sp. (Protozoa: Sarcocystidae) from the water buffalo (Bubalus bubalis) in Vietnam

Sarcocystis buffalonis n. sp. is proposed for a species forming thick-walled, macroscopic sarcocysts in skeletal muscles and the esophagus of the water buffalo (Bubalus bubalis). Sarcocysts of S. buffalonis were found in 68 (10.5%) of 647 buffalo carcasses examined grossly at slaughter in Ho Chi Minh City in southern Vietnam. Sarcocystis buffalonis sarcocysts were 1-8 mm long and 0.1-0.5 mm wide. The cyst wall was 3-7.7 microns thick and had palisadelike villar protrusions that were constricted at the base, expanded laterally in the mid-region, and tapered distally. The villar protrusions contained microfilaments and electron-dense granules. Sarcocysts of Sarcocystis fusiformis, the other well-known macroscopic species occurring in water buffalo, were also found in 60 of the 68 animals infected with S. buffalonis. Sarcocysts of S. fusiformis were thin walled and had characteristic cauliflowerlike villar protrusions. Two of 7 cats fed isolated S. buffalonis sarcocysts were found to have 12 x 8 microns sporocysts in their intestine or feces 10 days after inoculation.     

Schizorchis arfaai sp. n. (Cestoda: Anoplocephalidae) from the wood-mouse, Apodemus sylvaticus, in Caspian area of Iran

An artificial, slowly expanding mass which compressed the spinal cord produced histological, electrophysiological, and neurological changes. A comparison was made of the effects of laminectomy in the cat with dorsally and ventrally placed masses. Laminectomy reversed declining cord function and produced prompt recovery of somatosensory evoked potentials in cats with dorsally placed masses. In contrast, a worsening of these functions occurred following laminectomy in animals with ventrally placed masses. In all cases, evoked potential changes were consistent with neurological status and were predictive of the outcome of surgery.     

Comparative study of the venoms of three subspecies of Lachesis muta (bushmaster) from Brazil, Colombia and Costa Rica

A comparative study was performed on the pharmacology and biochemistry of venoms from three subspecies of Lachesis muta (L. m. stenophrys, L. m. muta and L. m. rhombeata) from Brazil, Colombia and Costa Rica. All venoms induced lethal, hemorrhagic, edema-forming, myotoxic, coagulant and defibrinating effects, showing also proteolytic and indirect hemolytic activities. The venoms of L. m. stenophrys from Costa Rica and L. m. muta from Cascalheira, Brazil, had the highest lethal and hemorrhagic activities and the venom of L. m. rhombeata showed the highest coagulant activity, whereas no significant differences were observed in myotoxic and edema-forming activities at most of the time intervals studied. In addition, venoms showed similar electrophoretic patterns on SDS-polyacrylamide gel electrophoresis. In conclusion, despite quantitative differences in toxic and enzymatic activities, together with subtle variations in electrophoretic patterns, our results indicate that experimental envenomation by these venoms induce a qualitatively similar pathophysiological profile.     

Subulura saloumensis n. sp. (Nematoda, Subuluroidea) from four species of rodents in Senegal

We recently reported that morphine inhibits growth of various human cancer cell lines (IC50/2.7-8.8 mM). We then extended the study using newly synthesized morphine derivatives, such as KT-90 and KT-87, which are analgesics 5 times more potent than morphine. KT-90 was found to inhibit growth of human cancer cell lines (IC50/42-70 microM) up to 80 times more potently than morphine. As for mechanisms of action, KT-90 and morphine induced apoptosis, and inhibited tumor necrosis factor alpha (TNF-alpha) gene expression induced by tumor promoters, okadaic acid and 12-O-tetradecanoylphorbol-13-acetate, associated with reduction of NF-kappaB DNA binding activity. This paper provides evidence that KT compounds confirmed the presence of anticancer activity of morphine in addition to its analgesic action.     

Monoecocestus thomasi sp. n. (Cestoda: Anoplocephalidae) from the northern flying squirrel, Glaucomys sabrinus (Shaw), in Oregon

Monoecocestus thomasi sp. n. (Cestoda: Anoplocephalidae), from the northern flying squirrel, Glaucomys sabrinus (Shaw), in Oregon, is described and distinguished from its congeners. Monoecocestus thomasi is the sixth species of Monoecocestus to be described from nearctic rodents, and the first from a member of the family Sciuridae. Our comparisons of taxonomic characters of the nominal species of Monoecocestus in North American rodents have shown that M. giganticus Buhler 1970 is a synonym of M. americanus (Stiles 1895), both from the porcupine, Erethizon dorsatum (Linnaeus). Insemination in Monoecocestus ssp. is discussed, with the conclusion that it takes place only by way of the vagina in early immature segments.     

Proteocephalus brooksi n. sp. (Cestoda:Proteocephalidae) in the neotropical freshwater fish Rhamdia guatemalensis (Siluriformes: Pimelodidae) from Lake Catemaco, Veracruz, Mexico

Proteocephalus brooksi n. sp. is described from the neotropical pimelodid fish Rhamdia guatemalensis from Lake Catemaco, Veracruz, México. The new species is characterized by the "paramuscular" position of vitellaria, the cortical origin of uterine stem with development of medullar lateral branches, the alternated position of vagina (anteriorly and posteriorly to cirrus sac), and the absence of apical organ and vaginal sphincter. Proteocephalus brooksi most closely resembles Nomimoscolex matogrossensis from which it differs in a series of characters. The probable paraphyletic nature of both Proteocephalus and Nomimoscolex and the convergent evolution of the "paramuscular" location of vitellaria among proteocephalideans are suggested, and the need for a phylogenetic analysis of the group is emphasized. The new species is assigned to Proteocephalus pending such an analysis.     

Isolation and characterization of a myotoxic phospholipase A2 from the venom of the arboreal snake Bothriechis (Bothrops) schlegelii from Costa Rica

PURPOSE: To evaluate the cytotoxicity of immunotoxin 4197X-ricin A (4197X-RA) and its ability to inhibit protein synthesis and human lens epithelial cell (LEC) proliferation on the inner surface of the lens capsule. SETTING: Houston Biotechnology, Inc., The Woodlands, Texas. METHODS: A cell culture system was established using human LECs as a model for the proliferation of remnant LECs that occurs during posterior capsule opacification (PCO) after extracapsular cataract extraction. The LEC culture system was also used in vitro for testing compounds that might inhibit this process in vivo. Human LECs were cultured on the surface of the original lens capsule fixed to collagen. Variability was reduced by dissecting each lens capsule into equivalent halves and exposing the segments to immunotoxin 4197X-RA. RESULTS: Protein synthesis and LEC proliferation were almost completely inhibited at relatively low 4197X-RA concentrations after short exposure. The inhibitory effects persisted up to 3 weeks after withdrawal of the immunotoxin and after several media exchanges. CONCLUSION: Immunotoxin 4197X-RA may help prevent PCO after primary cataract surgery.     

Oswaldocruzia venezuelensis sp. n. (Nematoda:Trichostrongylina, Molineoidea), a parasite of Bufo marinus from Venezuela

A new species of Oswaldocruzia Travassos, 1917, a parasite of Bufo marinus L. from Venezuela, is described. Like most Neotropical Oswaldocruzia, Oswaldocruzia venezuelensis sp. n. is characterized by spicules with three principal branches: blade, shoe and fork, and by a division of the fork within the distal third of the spicule length. O. vaucheri Ben Slimane et Durette-Desset, 1993 is the most closely related species due to its caudal bursa of type II and its cervical alae of the same shape but it differs in the following characters: the position of the papillae of rays 4 situated nearer the papillae of rays 3 rather than rays 5, a higher percentage of the ridges in the oesophageal region, the cervical alae three times longer and sharp and the spicular fork divided less deeply.