Movement of beta-irradiated epidermal basal cells to the spinous-granular layers in the absence of cell division.

Guinea-pig epidermis was irradiated with 3000 rad of beta rays 1 hr after two injections of [3-H]thymidine 5 hr apart (labeled cells in S phase and G2 phase) or 18 hr after injection (labeled early G1 cells). In nonirradiated epidermis labeled basal cells divided within 24 hr with daughter cells remaining in the basal layer, and approximately 50% of the labeled cells moved into the spinal layer by the 3rd day. Cell division in nonirradiated epidermis diluted the number of silver grains/nucleus, and lightly labeled cells were found in the granular layer by day 7. Beta irradiation inhibited cell division but it did not slow the rate of transit (ca 8 days) of irradiated labeled cells from basal to granular layer, some of these remaining heavily labeled. Although cell division may play some role in upward movement of basal cells in normal epidermis detachment of a basal cell from the basement membrane and its transit to the granular layer is unimpaired in the absence of cell division. These findings suggest that some radioresistant metabolic function(s), not cell division, is responsible for upward movement of basal cells.

Increased epidermal deoxyribonuclease I activity after clipping or plucking of hair and during wound healing.

An increase in extracellular epidermal DNase I occurs after slight to severe trauma to skin and appears to be generally associated with an inflammatory response including epidermal cell proliferation, rather than cell death. It precedes or accompanies the epidermal hyperplasia which occurs during healing of superficial wounds and regrowth of hair. It is suggested that extracellular epidermal DNase I is primarily of humoral origin and its increase after skin trauma results from increased vascular permeability and diffusion of a DNase I-inhibitor complex into the epidermis where the inhibitor is ultimately inactivated or destroyed.

Immunoglobulin G (IgG) levels in breast tumor cytosols.

Immunonephelometer investigation of specific proteins revealed a difference in levels of immunoglobulin G (IgG) found in the cytosol of estrogen receptor (ER) rich and estrogen receptor poor tumor tissue. Cytosols from estrogen receptor poor tumors had a significantly higher level of IgG than those from estrogen receptor rich tissues. The relationship between progesterone receptor levels and IgG was not as significant as that observed between ER levels and IgG. Other specific proteins did not correlate with either estrogen receptor levels or progesterone levels.

Views of child sexual abuse in two cultural communities: an exploratory study among African Americans and Latinos.

This exploratory study investigates knowledge and ideas about child sexual abuse among African Americans and Latinos through focus group discussions. Participants defined and described child sexual abuse, acknowledged that it occurred in their communities, and expressed their sense that family risk factors, risky institutions, and offender propensities were its root causes. Latino participants identified cultural transitions as another contributor. Responses and conversational style differed somewhat by gender and cultural identity. The authors discuss implications for child sexual abuse prevention, intervention, and research.

Evaluation of a child sexual abuse prevention program.

A half-million children are believed to be sexually abused each year in the United States. In 1995, the American Medical Association declared sexual assault "a silent violent epidemic." The majority of efforts to stop child sexual abuse have focused on punishing abusers and treating victims and their families; prevention programs are uncommon and rely on educating children to report sexual abuse. This case study describes the evaluation of the first public health campaign designed to target adults for prevention. A baseline assessment of attitudes, awareness, knowledge, and policies was conducted in Vermont to identify facilitators and barriers to adult prevention of child sexual abuse. These included predisposing factors (50% of Vermont residents did not know the characteristics of an abuser), enabling factors (60% of Vermont residents did not know where to refer someone who may have sexual behavior problems), and reinforcing factors (when focus group participants knew an abuser, they were less likely to take action). This process guided the intervention, which included a broad-based media campaign targeting adults; a one-to-one communications strategy that provided information to agencies working with families at risk and a toll-free helpline for adults in an abuse situation; and a systems change strategy designed to educate decision-makers and leaders. Program evaluation measures included a random-digit dial survey, focus groups, a survey of Vermont decision-makers, and other data sets. The successes and limitations of these interventions, both as strategies in themselves and as data sources for evaluation, are discussed.

Effect of needle puncture and intradermal fluid injection on epidermal cell kinetics of albino guinea-pig skin.

The flanks of male albino guinea pigs were used to study the effect of needle puncture with or without intradermal (id) injection of 0.1 ml fluid. The center of the raised bleb was marked and biopsies taken 1,4,8,24,50 and 72 hrs after needle puncture and 1 hr after intraperitoneal (ip) injection of tritiated thymidine (3H-TdR). There were no significant differences in labeling index (LI) or mitotic index (MI) 1 hr after id, ip, or subcutaneous (sc) injection nor in percent labeled mitoses, 7 hrs after id or ip injection. The earliest increase in LI (180% above control) occurred 12 hrs after needle puncture, peaked at 24 hrs (ca. 3X control), and returned to control level by 50 hrs. The area affected had a radius of about 5 mm from the point of needle entry or center of the bleb. Within 12 hrs after needle puncture, there was an increase in labeled cells primarily at the periphery of the bleb area, about 4 mm from the point of needle entry. By 24 hrs, the distribution of labeled cells had moved toward the bleb center (LI = 65%). The first increase in mitoses (MI = 2.5%) was seen 24 hrs after needle puncture. It is concluded that id injection introduces no significant error in LI or MI to 8 hrs after needle puncture. It does, however, trigger many noncycling basal cells into DNA synthesis after 8 hrs, and this may increase the rate of transit of these cells to the granular layer.