p53 expression and relation to human papillomavirus infection in pingueculae, pterygia, and limbal tumors.

BACKGROUND: The tumor suppressor gene p53 is expressed without apoptosis in the limbal basal stem cells of all pterygia and limbal tumors and most pingueculae from which these growths seem to originate. Oncogenic human papillomaviruses (HPVs) have been found in pterygia and limbal tumors, and HPV and p53 overexpression commonly coexist in oropharyngeal and penile carcinomas. OBJECTIVE: To search for HPV DNA as a cofactor in the development of pingueculae, pterygia, and limbal tumors. METHODS: We examined specimens--1 of pinguecula, 13 of pterygia (7 primary, 1 recurrent, 1 with dysplasia, and 4 primary not tested for p53), and 10 of limbal tumors (2 with actinic keratosis dysplasia, 1 with conjunctival intraepithelial neoplasia, 3 with carcinoma in situ, and 4 with squamous cell carcinoma)-expressing p53. Specimens were tested for the presence of HPV DNA by the polymerase chain reaction using degenerate consensus primers for the highly conserved portion of the L1 region that encodes a capsid protein of the virus. This assay has a wide spectrum with capability of detecting essentially all known HPV types. Nested polymerase chain reaction was performed on all specimens. Primers of the cystic fibrosis gene were used to confirm the presence of genomic DNA and to rule out inhibitors. Purified HPV DNA type 11 was the positive control, and HPV-negative genomic DNA was the negative control. RESULTS: Using consensus primers for the highly conserved portion of the L1 region, all specimens of pingueculae, pterygia, and limbal tumors studied were negative for HPV DNA by nested polymerase chain reaction. CONCLUSIONS: Human papillomavirus DNA is not required as a cofactor in the development of pterygia and limbal tumors. These data support the theory that increased p53 expression in the limbal epithelia of pingueculae, pterygia, and limbal tumors indicates the probable existence of p53 mutations in these cells as an early event in their development, which is consistent with UV irradiation causation. Thus, due to a damaged p53-dependent programmed cell death mechanism, mutations in other genes may be progressively acquired. This would allow for the multistep development of pterygia and limbal tumor cells from p53-mutated limbal epithelial basal stem cells overlying pingueculae.

The teaching of empathy for high school and college students: testing Rogerian methods with the Interpersonal Reactivity Index.

The teachability of empathy is discussed with particular regard to developmental issues. One hundred and four high school and college students were administered Davis's (1980) Interpersonal Reactivity Index (IRI) both before and after a standard course of Rogerian-based peer facilitation skills training. The IRI offers four independent subscales which measure the cognitive and affective components of empathy. Statistically significant findings indicate greater developmental readiness for learning empathic communication in the college sample, particularly for subscales measuring Empathic Concern and Perspective Taking. A group of untrained college students taking a course in behavioral psychology showed no progress on any IRI subscales. Although college females began with higher empathy scores, both genders were equally teachable. Implications for prevention and counseling readiness are discussed, along with suggestions for future research.

Heteroduplex formation: a potential source of genotyping error from PCR products.

The formation of heteroduplexes from polymerase chain reaction (PCR) products has recently become a diagnostic tool that is routinely used for the prenatal detection of small deletions or insertions in a number of disease-causing alleles. We present evidence illustrating that heterozygous PCR products can manifest 'invisible' heteroduplexes that can ultimately lead to genotyping errors. Justifications for these 'invisible' heteroduplexes and requisite parameters to optimize their detection are presented.

Prenatal diagnosis by enzymatic amplification and restriction endonuclease digestion for detection of haemoglobins A, S and C.

The detection of the single base pair mutations at codon 6 of the beta-globin gene is important for the prenatal diagnosis of sickle-cell anaemia and SC disease. A novel procedure has been designed to create a restriction site at both the beta A and beta C alleles to facilitate the discrimination of haemoglobins A, S and C. The general principle of this procedure is to enzymatically amplify genomic DNA using a modified primer containing an altered 3'-terminal nucleotide to create these restriction sites. After this modified primer has been efficiently incorporated into amplified DNA, the PCR products are digested with the restriction enzymes Ava I and Sty I. Ava I recognizes a site in amplified DNA containing a beta A allele, and Sty I recognizes a site in DNA containing a beta C allele. Since the beta A and beta C alleles can be distinguished directly by the presence of a restriction site, the beta S allele can be identified indirectly. All three beta-globin alleles are easily distinguished by size and pattern of electrophoresed fragments on agarose gels. This procedure is specific and sensitive, thus permitting rapid, economical diagnosis of sickle-cell anaemia and SC disease.

Rapid alkaline transfer of low molecular weight DNA from NuSieve GTG agarose gels.

The rapid alkaline transfer of high molecular weight DNA from agarose gels to nylon membranes has greatly decreased the time required for setup of Southern transfers. This technique has been used to resolve genomic DNA greater than 1000 base pairs by conventional electrophoresis on 1% agarose gels followed by alkaline transfer to nylon membrane. Now we report that this rapid alkaline method can be used for the transfer of low molecular weight DNA fragments (10 to 1000 base pairs) from NuSieve GTG agarose gels to nylon membrane.

The psychological experience of nursing mothers upon learning of a toxic substance in their breast milk.

This study explores the psychological reactions of a group of nursing mothers whose breast milk was inadvertently contaminated with a toxic fire-retardant chemical, polybrominated bihenyl. In particular, the extent to which the 97 mothers in the study denied the presence and possible effects of the chemical in their offspring is examined. Corresponding psychological defenses and reactions such as guilt or ambivalence in the nursing relationship and efforts at mastery of the situation are described with accompanying clinical illustrations. Insofar as the presence of a variety of toxic chemicals in the environment has been reported, the psychological reactions discussed here may have widespread application.

The adolescent experience of pregnancy and abortion: a developmental analysis.

PIP: Previous literature suggests that illegitimate pregnancy is a consequence of demographic factors, idiosyncratic family situations, or neurotic conditions. The author rejects these conclusions and hypothesizes that the experience of pregnancy in adolescence may be the reflection of an exacerbated developmental crisis. 3 clinically and statistically significant patterns in the experience of and motivation for pregnancy and abortion emerge, 1 for each of the 3 adolescent substages: early, middle, and late. 13 unwed pregnant adolescents were included in an in-depth study. The girls were between 15 and 26 years old, all middle class. The 5 areas used as measures of developmental stages were 1) the person most related to the girl's conflicts, 2) the quality and style of object relationships, 3) the girl's view of herself, 4) her use of defense mechanisms, and 5) her goals and interests. From their answers, the girls were divided into the 3 adolescent groups. Age, demographic characteristics, and diagnosed personality style do not correlate with stages of adolescence. Attitudes having to do with the pregnancy were tested along the following lines: 1) knowledge of conception and contraception, 2) motivations for the pregnancy, 3) experience of pregnancy, 4) experience and anticipation of motherhood, 5) attitudes toward abortion, 6) perception of the fetus, 7) fantasies of change, and 8) sense of the effect of the pregnancy on the future. The answers given grouped themselves more or less according to the 3 groups of adolescence into which the girls had previously been divided. Each adolescent group viewed the pregnancy differently. No deleterious effects and no striking gains resulted from the abortions. The girls who appeared to mature most from the experience were those already closest to maturity.^ieng