Expression of aldehyde dehydrogenase 1 as a marker of mammary stem cells in benign and malignant breast lesions of Ghanaian women

BACKGROUND:

Breast cancers that are negative for the estrogen receptor (ER), the progesterone receptor (PR), and the HER2 (human epidermal growth factor receptor 2) marker are more prevalent among African women, and the biologically aggressive nature of these triple‐negative breast cancers (TNBCs) may be attributed to their mammary stem cell features. Little is known about expression of the mammary stem cell marker aldehyde dehydrogenase 1 (ALDH1) in African women. Novel data are reported regarding ALDH1 expression in benign and cancerous breast tissue of Ghanaian women.

METHODS:

Formalin‐fixed, paraffin‐embedded specimens were transported from the Komfo Anoyke Teaching Hospital in Kumasi, Ghana to the University of Michigan for centralized histopathology study. Expression of ER, PR, HER2, and ALDH1 was assessed by immunohistochemistry. ALDH1 staining was further characterized by its presence in stromal versus epithelial and/or tumor components of tissue.

RESULTS:

A total of 173 women contributed to this study: 69 with benign breast conditions, mean age 24 years, and 104 with breast cancer, mean age 49 years. The proportion of benign breast conditions expressing stromal ALDH1 (n = 40, 58%) was significantly higher than those with cancer (n = 44, 42.3%) (P = .043). Among the cancers, TNBC had the highest prevalence of ALDH1 expression, either in stroma or in epithelial cells. More than 2‐fold higher likelihood of ALDH1 expression was observed in TNBC cases compared with other breast cancer subtypes (odds ratio = 2.38, 95% confidence interval 1.03‐5.52, P = .042).

CONCLUSIONS:

ALDH1 expression was higher in stromal components of benign compared with cancerous lesions. Of the ER‐, PR‐, and HER2‐defined subtypes of breast cancer, expression of ALDH1 was highest in TNBC. Cancer 2013. © 2012 American Cancer Society.     

Sensitivity of primary fibroblasts in culture to atmospheric oxygen does not correlate with species lifespan

Differences in the way human and mouse fibroblasts experience senescence in culture had long puzzled researchers. While senescence of human cells is mediated by telomere shortening, Parrinello et al. demonstrated that senescence of mouse cells is caused by extreme oxygen sensitivity. It was hypothesized that the striking difference in oxygen sensitivity between mouse and human cells explains their different rates of aging. To test if this hypothesis is broadly applicable, we cultured cells from 16 rodent species with diverse lifespans in 3% and 21% oxygen and compared their growth rates. Unexpectedly, fibroblasts derived from laboratory mouse strains were the only cells demonstrating extreme sensitivity to oxygen. Cells from hamster, muskrat, woodchuck, capybara, blind mole rat, paca, squirrel, beaver, naked mole rat and wild-caught mice were mildly sensitive to oxygen, while cells from rat, gerbil, deer mouse, chipmunk, guinea pig and chinchilla showed no difference in the growth rate between 3% and 21% oxygen. We conclude that, although the growth of primary fibroblasts is generally improved by maintaining cells in 3% oxygen, the extreme oxygen sensitivity is a peculiarity of laboratory mouse strains, possibly related to their very long telomeres, and fibroblast oxygen sensitivity does not directly correlate with species'' lifespan.     

The psychosocial impact and developmental implications of the threat of nuclear war on adolescents

The particular significance of the threat of nuclear war in relation to the lifeview of the 270 Midwestern adolescents in our study appears manifest in the high level of awareness and concern a majority show regarding the imminence of nuclear war — its unlimitability, unsurvivability, and probability in their lifetime — and in the significant correlations demonstrated: The most highly threatened are also the more pessimistic about the future — for both the world and themselves, the more sceptical of the efficacy of socio‐political activism, and the more critical of adult stewardship. The intensity of these youngsters' feelings about the threat of nuclear war, their uncertainty about the future, and the depth of their disappointment and disapproval of adults' management of these matters and world affairs may be testimony to a substantial compromising of trust and faith in the parental generation.     

Steroidogenesis in the adrenal dysfunction of critical illness: impact of etomidate

ABSTRACT: INTRODUCTION: This study was aimed at characterizing basal and adrenocorticotropic hormone (ACTH)-induced steroidogenesis in sepsis and nonsepsis patients with a suspicion of critical illness-related corticosteroid insufficiency (CIRCI), taking the use of etomidate-inhibiting 11β-hydroxylase into account. METHOD: This was a prospective study in a mixed surgical/medical intensive care unit (ICU) of a university hospital. The patients were 62 critically ill patients with a clinical suspicion of CIRCI. The patients underwent a 250-μg ACTH test (n = 67). ACTH, adrenal steroids, substrates, and precursors (modified tandem mass spectrometry) also were measured. Clinical characteristics including use of etomidate to facilitate intubation (n = 14 within 72 hours of ACTH testing) were recorded. RESULTS: At the time of ACTH testing, patients had septic (n = 43) or nonseptic critical illness (n = 24). Baseline cortisol directly related to sepsis and endogenous ACTH, independent of etomidate use. Etomidate was associated with a lower baseline cortisol and cortisol/11β-deoxycortisol ratio as well as higher 11β-deoxycortisol, reflecting greater 11β-hydroxylase inhibition in nonsepsis than in sepsis. Cortisol increases < 250 mM in exogenous ACTH were associated with relatively low baseline (HDL-) cholesterol, and high endogenous ACTH with low cortisol/ACTH ratio, independent of etomidate. Although cortisol increases with exogenous ACTH, levels were lower in sepsis than in nonsepsis patients, and etomidate was associated with diminished increases in cortisol with exogenous ACTH, so that its use increased, albeit nonsignificantly, low cortisol increases to exogenous ACTH from 38% to 57%, in both conditions. CONCLUSIONS: A single dose of etomidate may attenuate stimulated more than basal cortisol synthesis. However, it may only partly contribute, particularly in the stressed sepsis patient, to the adrenal dysfunction of CIRCI, in addition to substrate deficiency.     

An evaluation of the Africa Midwives Research Network

Objectiveto evaluate the strengths and limitations of the Africa Midwives Research Network (AMRN) and provide feedback and direction to the network and the funding body.Designa qualitative study incorporating visits to three African countries and Sweden, using interviews, non-participant observation, an internet survey and review of records.Settingprincipally Tanzania, Uganda, Zambia and Sweden.FindingsAMRN can be described as a small, dispersed, loosely coupled professional network which has made considerable impact on midwifery practice in the areas of its members. The biennial scientific conferences could be perceived as AMRN's flagship activity and have been notably successful, becoming renowned internationally. Around 1500 midwives have benefited from educational programmes at regional or national level. These include research methodology, evidence-based practice, scientific writing and communication skills. Attention needs to be given to some aspects of governance and organization, as well as to communication strategies including websites and newsletters. Technical support from the Karolinska Institute in Stockholm has provided good collegiate support and proved to be cost effective.Key conclusionsAMRN has shown resilience and continuity since its inception and has made a palpable difference to the quality of midwifery care and the professional development of midwives within the remit of its members. AMRN needs to be consolidated before expanding further. The work of AMRN is particularly pertinent in the context of the millennium development goals.