Recent advances in retrolental fibroplasia

Retrolental fibroplasia is the most common cause of preschool blindness. Changes identical to retrolental fibroplasia in humans have been produced in animals by exposing them to high oxygen concentration. Oxygen should be ordered for premature infants in a careful and precise manner. Concentrations of over 40 per cent should be avoided whenever possible. Withdrawal to air should be a gradual process.     

Phenotypic Variation and Systemic Cancer in the FAMMM Syndrome

Familial atypical multiple mole melanoma (FAMMM) syndrome, a cancer-associated genodermatosis, is a dominantly inherited heterogeneous disorder with variable expressivity of both its cutaneous and cancer phenotypes. By using a verified historical review technique of cancer documentation (idout patient health records, pathology reports/slides, autopsy reports/slides, and death certificates) of all anatomic sites in all members of a modified nuclear pedigree (first-degree relatives plus maternal and paternal grandparents, aunts, and uncles) over several generations, we showed that the FAMMM syndrome is similar to the majority of autosomal dominant inherited cancer-associated genodermatoses and has excessive risk for cancer of multiple anatomic sites. With respect to the FAMMM syndrome, these cancers involved the breast, respiratory tract, gastrointestinal system, the eye (intraocular melanoma), and the lymphatic system. These FAMMM pedigrees showed some of the following distinctive characteristics of hereditary cancer: 1) integral patterns of cancer within and between pedigrees; 2) early age of onset of cancer; 3) prolonged survival of some pedigree members with cancer; and 4) an excess of multiple primary melanomas and cancers of variable anatomic sites. The presence of these features indicates that these cancers of variable anatomic sites may be etiologically associated with the FAMMM syndrome. Heterogeneity should be investigated in FAMMM pedigrees with attention to consistent differences in size and distribution of atypical lesions, age at cancer onset, and pattern of tumor occurrences. The occurrence of FAMMM pedigrees in the general population or among pedigrees of probands with atypical nevi is not known. The occurrence of systemic cancers in these FAMMM pedigrees requires the development of cancer surveillance programs that are specifically modified to the particular cancer pattern of each pedigree.     

Successful Demonstration of an Elusive Cell Coat in Amebae*

SYNOPSIS. Cell coats were cytochemically demonstrated for the first time in myxamebae of Fuligo septica, Didymium iridis, Dictyostelium discoideum, Cavostelium apophysatum, and amebae of Naegleria gruberi. The stain enhances the cell coats of Physarum polycephalum plasmodia, Ceratiomyxa fruticulosa myxamebae, and Acanthamoeba sp. Cell coats usually unstained by cationic dyes stain intensely with the aid of the new cytochemical protocol utilizing 0.5% Alcian blue in the primary fixative and 0.05% ruthenium red in the secondary fixative.     

The Plastic Growth Responses of Three Agamospecies of Dandelion to Two Levels of Nutrient

The ability of a genotype to produce different phenotypes inresponse to variable environments is a crucial aspect of lifehistory strategies as it determines the shape of the fitnessset for the population. Apomictic dandelions generate littlegenetic variation between parent and offspring and plasticityis the main strategy in the face of environmental variability.The plastic response of three coexisiting dandelions has beenmeasured over two nutrient regimes. Cyclical growth patternsare species specific and in some cases independent of nutrientlevels. Differences between the agamospecies are greater athigh nutrient levels and the agamospecies appear to produceonly one phenotype at low nutrient levels. Taraxacum, plasticity, phenotypes, nutrient level