Enteroparasitoses and Toxocarosis Affecting Children from Mar del Plata City,Argentina

This study evaluated the existence of enteroparasitoses and toxocarosis in children of peripheral (PC) and urban communities (UC) from Mar del Plata city (Argentina) and their associations with socio-environmental conditions. A Parasite Vulnerability Index (PVI) was elaborated using variables such as overcrowding, floor type, drinking water source, wastewater disposal, solid waste disposal, presence of animals and schooling level. The PC evidenced statistically significant higher frequencies of families with high (38.9%) and medium (55.5%) PVI, while in the UC low PVI (93%) was the most frequent. A statistically significant higher frequency of PC children was parasitized (30.2 vs. 14.5%; χ ² Pearson = 5.21; P < 0.05), presented higher parasite frequencies, specific richness, parasitic loads, and they also evidenced polyparasitism. The Multiple Correspondence Analysis (MCA) showed associations between PC-parasitized children, overcrowding and contact with pets and farm animals. The ELISA test to the specified determination of Toxocara canis IgG was reactive in a statistically significant higher proportion of PC children than the UC (55 vs. 8.5%; χ ² = 30.5; P < 0.01). The MCA associated PC reactive children, not adequate hand washing, moderate and hypereosinophilia and contact with pets and farm animals. Deficient socio-environmental conditions became children more vulnerable to get enteroparasitoses and toxocarosis in the PC than in the UC.     

Seasonal airborne pollen pattern in Mar del Plata City, Argentina

Continuous aerobiological survey of the atmosphere of Mar del Plata was carried out from December 1991 to November 1993 with a Burkard volumetric spore trap. Daily slides were prepared and studied every 2 h with standard techniques. Weekly records were kept for 27 relevant pollen types selected either by their prevalence or relative high atmospheric concentration. Quantitative multivariate analysis enabled to distinguish three major pollen seasons, related to atmospheric dominance either arboreal pollen (AP) or non-arboreal pollen (NAP). June to October is the richest period in number of pollen types, mainly dominated by AP; while from November to May, there is an overwhelming dominance of NAP types, represented by grass, herb and weed pollen. The study and prediction of this phenomenon is of great interest not only from the ecosystem point of view, but in relation to human disease as well.     

Comparison of diurnal variation of airborne pollen in Mar del Plata (Argentina)

Intradiurnal variation of arboreal pollen (AP) in Mar del Plata city is compared during three non - consecutive years of survey and described in relation to the associated weather. The daily pattern of pollen abundance has a maximum between 10:00 and 12:00?h, while a minimum occurs at 18:00?h. The first two years of survey showed homogeneous daily trends, but in 1995 the maximum and minimum concentrations were delayed because of the change in position of the collecting station. Arboreal pollen spectrum presented qualitative and quantitative changes in the three years analysed. Results indicate optimal conditions for diurnal dispersion of arboreal pollen are high temperatures and low relative humidity. Also interaction between source position and wind direction has important effects on the timing of the peaks of some pollen types.     

Reproductive cycle of the sea cucumber Psolus patagonicus Ekman 1925, off Mar del Plata,Buenos Aires,Argentina

The reproductive cycle of Psolus patagonicus Ekman 1925 was studied. The species exhibits an annual reproductive cycle with one reproductive period in austral summer (February–March). During spring and summer, females showed the highest gonad-index (GI) values, while the GI values of males did not vary significantly throughout the year. Males had higher GI values than females. Maximum oocyte diameters ranged from less than 300?µm in spring to 900?µm in summer. In February, there is an increase in phytoplankton bloom for the bottom community in which P. patagonicus inhabits. The annual range in water temperature is small (6–7°C). Spawning coincided with increase in available food rather than the increase in water temperature.     

Comparison between phenological and aerobiological patterns of some arboreal species of Mar del Plata (Argentina)

An atmospheric pollen survey and a periodical quantitative check of the flowering phases of trees were performed during 1993. Most of specific flowering seasons lasted from 4 to 8 weeks. October is the month with the highest number of species in bloom. Anemophylous species flower mainly in coincidence with the relatively low temperatures of late winter and early spring, while the enthomophylous ones correlate with the high temperatures of late spring and summer. The anemophylous ‘community’ follow a sigmoid pattern with respect to both the flowering development and the cumulative pollen concentration. Agreement between floral phenophases and pollen counts were evaluated for 14 genera (27 species). Pollen data of anemophylous species coincide fairly well with the phenological behaviour. Particular features must be taken into account to interpret this relationship.     

New records of Aphyonidae (Teleostei: Ophidiiformes) from the south-western Atlantic

During austral summer and winter of 2003, three specimens of Aphyonus gelatinosus and one specimen of Barathronus bicolor (Ophidiiformes: Aphyonidae) were trawled off Rio de Janeiro, Brazil.     

Trajectories associated to regional and extra-regional pollen transport in the southeast of Buenos Aires province, Mar del Plata (Argentina)

Long range transport of airborne pollen has been seldom studied in South America. Backward trajectories of Celtis and Nothofagus pollen grains trapped over a meteorological station outside Mar del Plata City were calculated in one-hour steps using the regional hybrid model developed by the NOAA (HYSPLIT 4.5) and the data of the NCEP filed in the NOAA server. Results showed that the observed trajectories agree with the location of vegetation sources of the collected tree species. In the case of Celtis, the transport was associated to anticyclones located east of the city, generating winds with a N-NE component, which produce pollen cloud advection from the Celtis forests located some tens of kilometers to the N and NE of the city. The sources of Nothofagus pollen correspond to a narrow strip on the Andes slopes between 39° and 55°S, at least 1100 km to the SW of Mar del Plata. The transport was associated to eastward displacement of the troughs corresponding to the Westerlies circulation and the presence of an anticyclone system that brings back Nothofagus pollen towards Mar del Plata area.     

Comparison of intradiurnal variation of airborne pollen in Mar del Plata (Argentina). Part I. Non-arboreal pollen

Intradiurnal variation of non-arboreal pollen (NAP) aredescribed in relation to the associated weather using the data obtainedwith a Burkard trap in Mar del Plata city, for a three year data set(1988, 1992 and 1995). The daily pattern of concentration was quitehomogeneous during the years analysed except for 1995, when it showed avariation due to the change of position of the station. Qualitativecomposition of the NAP airborne pollen was mainly represented byPoaceae, Plantago and Cyperaceae during the three years. The daily trendshowed high concentrations during daylight hours, when instability andconvective movements prevail, and low concentrations in the night, whenmeteorological conditions favour the development of a stable stratifiedlayer.     

A new species of Cardicola Short, 1953 (Digenea: Sanguinicolidae) parasitizing the Brazilian flathead, Percophis brasiliensis Quoy et Gaimard 1824, from the coasts of Mar del Plata, Argentina

Cardicola ambrosioi n. sp. (Digenea: Sanguinicolidae) is found in the blood vessels of liver and gills of the Brazilian flathead, Percophis brasiliensis Quoy and Gaimard, 1824 (Pisces: Percophidae), from Mar del Plata, Argentina. Among the 13 known species within Cardicola Short, 1953, the new species closely resembles Cardicola coridodacis Manter, 1954, from which it is distinguished by having a relatively shorter oesophagus, the vitellaria extending anteriorly to the nerve commissure, rather than to the end of anterior caeca, the female pore located closer to male pore, the latter situated medially instead of laterally and by possessing a larger Mehlis gland and a smaller seminal vesicle.     

New species of dictyostelids from Patagonia and Tierra del Fuego, Argentina

In late Jan and early Feb 2005 samples for isolation of dictyostelid cellular slime molds (dictyostelids) were collected in five different provinces and from six national parks (all located 39-55°S) in Patagonia and Tierra del Fuego, Argentina. Southern beech (Nothofagus) forests represented the primary vegetation type investigated, but some samples were obtained from Patagonian steppe, alpine meadows, Valdivian temperate rainforests and coniferous forests dominated by Araucaria, Austrocedrus and Fitzroya. Among the dictyostelids isolated from the samples we collected were seven species new to science. These species (Dictyostelium austroandinum, D. chordatum, D. fasciculoideum, D. gargantuum, D. leptosomopsis, D. valdivianum and Polysphondylium patagonicum) are described herein on the basis of both morphology and molecular (SSU rDNA) data. One of the new species, D. gargantuum, is one of the largest representatives of the group reported to date. Another unusual species, D. chordatum, produces long interwoven sorocarps that do not appear to respond to a spacing gas similar to the condition first noted in D. implicatum.     

Bitter crab syndrome in two species of king crabs from the Sea of Okhotsk

The disease caused by parasitic dinoflagellates of the genus Hematodinium was found in the red Paralithodes camtschaticus and blue P. platypus king crabs from the Sea of Okhotsk. The hemolymph of diseased crabs was cream colored, opaque, and dense. Numerous dinokaryotic trophonts and multinucleate plasmodia of the parasite were revealed in the hemolymph and internals of diseased animals. The parasitic infection was recorded in females and juvenile males from August to mid-October.     

First record of the genus Jenynsia from marine water on the coast of Punta del Este,Maldonado, Uruguay (Cyprinodontiformes: Anablepidae)

The first report of the genus Jenynsia occurring in marine waters is presented here. The evolution of high salinity tolerance within Anablepidae is discussed and a hypothesis is proposed that this characteristic is a plesiomorphic trait in Jenynsia which was probably present in the common ancestor of the Anablepidae.     

A new species of viviparous brotula genus Pseudogilbia (Ophidiiformes: Dinematichthyidae) from Brazilian reefs,with an updated diagnosis of the genus

In this study, a new species of Pseudogilbia Møller, Schwarzhans & Nielsen 2004 is described based on two male specimens (40–44 mm L_S) from shallow reefs of Bahia, Brazil. Pseudogilbia australis sp. nov. is distinguished from its only congener, Pseudogilbia sanblasensis Møller, Schwarzhans & Nielsen 2004 from Caribbean Panama, by having: two lower preopercular pores (vs. one); dorsal-fin rays 65–67 (vs. 69); anal-fin rays 51–53 (vs. 56); pectoral-fin rays 18 (vs. 20); caudal vertebrae 27–28 (vs. 30); pectoral-fin length 15.0%–15.9% L_S (vs. 14.3); pelvic-fin length 13.5% L_S (vs. 16.4) and a different morphology of the male copulatory organ. Pseudogilbia australis sp. nov. is the only dinematichthyid so far recorded in the South Atlantic. An updated diagnosis for the genus is also provided.     

Histones from spermatozoa of the horseshoe crab

It is shown that histones are the nuclear proteins present in spermatozoa of the horseshoe crab Limmulus polyphemus, an arthropod which is considered a living fossil. They have been characterized and found to be closely related to calf thymus histones. The only difference is the presence of an additional histone in small amounts (2?3% of the whole histones) which has intermediate properties between H1 and H2b.     

A new enveloped helical virus from the blue crab,Callinectes sapidus

Quite different ultrastructural changes were observed in the columnar cell and the goblet cell of the silkworm midgut after administration of the crystalline toxin of Bacillus thuringiensis. Shortly after the ingestion of the toxin, the deep infoldings of the basal cell membrane of some columnar cells became very irregular in shape and the mitochondria near the basal region were transformed into a condensed form. A few goblet cells showed relatively high electron density in the cytoplasm. The earliest pathological changes were slight and located in a region lying between the first and second thirds of the midgut. With the passage of time, they spread anteriorly and posteriorly to include the entire anterior two thirds of the midgut and became more profound. The cytoplasm of columnar cells became very electron transparent. Most mitochondria were transformed into a condensed form and the endoplasmic reticulum assumed a vacuole-like configuration. The basal infoldings of the cell membrane almost disappeared. On the other hand, the cytoplasm of the goblet cells became very electron dense and granular. The clear basal infoldings of the cell membrane were enlarged making a striking contrast with the dense cytoplasm. However, the mitochondria and the endoplasmic reticulum did not show any pathological deformation.