Technician Training in Environmental Health Science

In colleges and universities across the country, courses in ecology and environmental science are among the newest additions to the catalog. The goal of such courses is to make students aware of the environmental dilemma, a just and necessary goal. However, there is a need to do more than this. Jobs dealing with environmental protection are becoming more and more complex due to the recent passage of State and Federal legislation, which includes the Clean Air Act, the Amendments to the Water Pollution Control Act and the Occupational Safety and Health Act, just to name a few. Trained personnel are needed by industry and government. For this reason, in 1971, Middlesex County College initiated an Environmental Health Science Technology Program.     

Invasive vermigon stage in the parasitic barnacles Loxothylacus texanus and L. panopaei (Sacculinidae): closing of the rhizocephalan life-cycle

 The parasitic barnacles, Rhizocephala, are unique in Crustacea by having an entirely endo-parasitic phase inserted into their lifecycle. A cypris larva, remarkably similar to the cypris of conventional acorn and goose barnacles (Thoracica), settles on the crustacean host and develops an infective stage, the kentrogon, underneath the exuviae of the cypris. The kentrogon penetrates the integument of the host by a hollow cuticle structure, the stylet, and injects the parasitic material into the hemocoelic fluid of the host. Although advanced stages of the internal development have been found and described several times, the nature of the originally injected parasitic material has remained obscure for decades. Recently, however, it was shown that the parasitic material was injected by the kentrogon in the form of a motile, multi-cellular and vermiform body. The present study demonstrates that the vermiform stage is an instar which forms the only and direct link between the kentrogon and the maturing internal parasite. The vermiform instar, or vermigon, is at all times clothed in a cuticle, contains several types of cells, including epidermis and the anlage of the later ovary, and stays intact while growing into the internal parasites with rootlets. Received: 12 August 1999 / Accepted: 3 November 1999     

Extra-pair fertilizations in mountain white-crowned sparrows

Summary A population of white-crowned sparrows (Zonotrichia leucophrys oriantha) located near Tioga Pass, in the central Sierra Nevada of California, was studied during the 1985 and 1986 breeding seasons to determine how often chicks were not the offspring of both adults who reared them. Blood samples were obtained from 35 nesting pairs and feather pulp specimens were collected from all 110 young they fledged. Electrophoretic analyses of 4 polymorphic loci revealed that a minimum of 9 nests (26%) contained a chick that could not have been conceived in a mating between the attending pair, and that at least 15 chicks (14%) were not offspring of both attending adults. Using two recently developed probability indices, it was estimated that 34%–38% of chicks hatched at the study site were not offspring of one of their putative parents. Because there was no evidence that intraspecific brood parasitism occurred, all the mismatched young apparently resulted from extrapair copulations. Our data, along with similar results from other species, raise new questions about sexual selection and patterns of parental care in monogamous birds.     

Linking community and national park development: A case from the Dominican Republic

National parks have complex relationships with local communities that impact both conservation success and community well-being. Integrated conservation and development projects have been a key approach to managing these relationships, although their effectiveness has been increasingly questioned. Park-people relationships of the Armando Bermudez National Park in the Dominican Republic were studied, focusing on forests, aquatic resources, community well-being and development, and ecotourism. The park, established in 1956, is well respected by the community, based on its long history and its role in protecting water resources that are critical to the community. However, management of riparian vegetation and local fisheries present challenges in terms of finding a balance between conservation and development. Hiking and trekking opportunities attract both national and international tourists to the park, and community members benefit from employment as tour guides and providing mule rentals. At the same time, tourism activities also present continuing challenges related to: (1) the distribution of tourism benefits between local people and outsiders, and within the local community, (2) maintaining the local economic benefits of tourism while protecting park resources, and (3) developing park- or conservation-related economic opportunities to complement tourism. The results highlight the need to develop site-specific strategies to manage park-people relationships through interdisciplinary analysis.     

Transvaginal chorionic villus sampling using transabdominal ultrasound guidance

Transvaginal chorionic villus sampling (CVS) using concurrent transabdominal ultrasound guidance was performed in six women who desired CVS but could not be offered transcervical or transabdominal approaches because of uterine position and placental location. Satisfactory amounts of chorionic villi were obtained in all six cases with no maternal discomfort, an occurrence that contrasts with our experience in transvaginal CVS using endovaginal ultrasound guidance. We believe that transvaginal CVS using concurrent transabdominal ultrasound guidance warrants consideration as an alternative technique for first-trimester CVS in selected patients.     

Isolating fetal nucleated red blood cells from maternal blood: The baylor experience—1995

In our previous work we have isolated fetal cells from maternal blood and used fluorescent in situ hybridization (FISH) for chromosome-specific probes to detect aneuploidy. Current efforts in the Baylor College of Medicine programme are focusing on obtaining consistency in flow-sorting methodology and on determining sensitivity and specificity. To this end, systematic evaluation of five glycophorin A (gly A) antibodies all produced agglutination, leading us to abandon the use of gly A antibodies for positive selection of fetal cells. Conversely, we have found LDS-751 to be useful for nuclear selection. CD45 negative selection can best be accomplished by the use of flasks coated with goat antibodies against mouse antibodies. Positive selection by flow sorting for either CD71⁺ cells or gamma-globin-positive cells seems to be successful. Using these two approaches, we have recently detected male (fetal) cells in pregnancies in which the fetus was 46, XY in 10 of 18 and in 12 of 14 cases, respectively.     

Significance of septations in isolated fetal cystic hygroma detected in the first trimester

Recent reports have indicated an increased risk for fetal chromosome abnormalities, especially autosomal trisomy, in fetuses with isolated cystic hygroma, or prominent nuchal membranes, detected by ultrasonography during the first trimester. However, these reports present contradictory information regarding the prognostic significance of septations within the cystic hygroma. We evaluated, in blind fashion, 55 consecutive cases of isolatd fetal cystic hygroma detected at or before 13·9 weeks' gestation to determine the association between septations and fetal chromosome complement. Septations were associated (P<0·05) with an increased risk for fetal chromosome abnormalities. However, the incidence of chromosome abnormalities was also increased (12·5 per cent) among cases not characterized by septations. Thus, we believe it prudent to offer invasive prenatal testing to all women found to be carrying fetuses with cystic hygroma, irrespective of the presence or absence of septations.