Malignant Phyllodes Tumor: Imaging Features With Histopathologic Correlation.

Phyllodes tumors (PT) are rare fibroepithelial lesions of the breast that commonly present as rapidly enlarging, palpable masses. Phyllodes tumors may be classified as benign, borderline, or malignant on the basis of histopathologic analysis. Although malignant PT cannot be distinguished from benign PT on the basis of imaging findings alone, studies suggest that malignant PT tend to be larger and irregular in shape, and they are less likely to have circumscribed margins. If biopsy results are indeterminate, excisional biopsy should be performed. Malignant PT can be difficult to distinguish histologically from sarcomas and spindle cell metaplastic breast carcinoma; the distinction is important for prognosis and treatment. Malignant PT are treated surgically with wide local excision, without a clear role for adjuvant radiation or chemotherapy in most cases. Nearly one-third of malignant PT recur locally, usually within a few years after initial diagnosis. Distant metastatic disease is rare, and the five-year overall survival rate of malignant PT is close to 80%. The purpose of this article is to review the clinical presentation, imaging appearance, histopathology, and management of malignant PT.

Impacts of highway traffic exhaust in alpine valleys on the respiratory health in adults: a cross-sectional study.

BACKGROUND: Most studies having shown respiratory health effects from traffic exhaust were conducted in urban areas with a complex mixture of air pollution sources. This study has investigated the potential impact of traffic exhaust on respiratory symptoms among adults living along a Swiss alpine highway corridor, where traffic exhaust from the respective trans-Alpine highway is the predominate source of air pollution. METHODS: In summer 2005, we recruited 1839 adults aged 15 to 70 from a random sample of 10 communities along the Swiss alpine highway corridors. Subjects answered a questionnaire on respiratory health (asthmatic and bronchitic symptoms), risk factors, and potential confounding variables. We used logistic regression models to assess associations between respiratory symptoms and traffic exposure being defined a) as living within 200 m of the highway, and b) as a bell-shaped function simulating the decrease of pollution levels with increasing distance to the highway. RESULTS: Positive associations were found between living close to a highway and wheezing without cold (OR = 3.10, 95%-CI: 1.27-7.55) and chronic cough (OR = 2.88, 95%-CI: 1.17-7.05). The models using a bell-shaped function suggested that symptoms reached background levels after 400-500 m from the highway. The association with chronic cough was driven by a subgroup reporting hay fever or allergic rhinitis. CONCLUSIONS: Highway traffic exhaust in alpine highway corridors, in the absence of other industrial sources, showed negative associations with the respiratory health of adults, higher than those previously found in urban areas.

Improvements in PM10 exposure and reduced rates of respiratory symptoms in a cohort of Swiss adults (SAPALDIA).

RATIONALE: Reductions in mortality following improvements in air quality were documented by several studies, and our group found, in an earlier analysis, that decreasing particulate levels attenuate lung function decline in adults. OBJECTIVES: We investigated whether decreases in particulates with an aerodynamic diameter of less than 10 microm (PM10) were associated with lower rates of reporting respiratory symptoms (i.e., decreased morbidity) on follow-up. METHODS: The present analysis includes 7,019 subjects who underwent detailed baseline examinations in 1991 and a follow-up interview in 2002. Each subject was assigned model-based estimates of average PM10 during the 12 months preceding each health assessment and the difference was used as the exposure variable of interest (DeltaPM10). Analyses were stratified by symptom status at baseline and associations between DeltaPM10 and change in symptom status during follow-up were adjusted for important baseline characteristics, smoking status at follow-up, and season. We then estimated adjusted odds ratios for symptoms at follow-up and numbers of symptomatic cases prevented due to the observed reductions in PM10. MEASUREMENTS AND MAIN RESULTS: Residential exposure to PM10 was lower in 2002 than in 1991 (mean decline 6.2 microg/m3; SD = 3.9 microg/m3). Estimated benefits (per 10,000 persons) attributable to the observed changes in PM10-levels were: 259 (95% confidence interval [CI]: 102-416) fewer subjects with regular cough, 179 (95% CI, 30-328) fewer subjects with chronic cough or phlegm and 137 (95% CI, 9-266) fewer subjects with wheezing and breathlessness. CONCLUSIONS: Reductions in particle levels in Switzerland over the 11-year follow-up period had a beneficial effect on respiratory symptoms among adults.

Phosphorylation status of c-Kit and Epo receptors, and the presence of wild-type p53 confer in vitro resistance of murine erythroleukemic cells to Celecoxib.

It is well established that selective COX-2 inhibitors exhibit potent effects against progression of select solid tumours. However, their effects on liquid tumours have not been fully established. By taking advantage of murine Friend Disease we have shown a strong antileukemic effect of celecoxib by determining novel in vitro targets. Western blot analyses revealed the expression of COX-2 in a panel of Friend Virus-transformed, splenic-derived primary erythroleukemic blasts and established cell lines generated in our laboratory. We have shown that celecoxib at concentrations as low as 20 microM significantly suppresses proliferation of the selected murine erythroleukemia cell line HB60-5. The greatest proliferative inhibition was seen at 40 microM of celecoxib, resulting in apoptosis. Our results also demonstrate that treatment of the established murine erythroleukemia cell line HB60-5 with celecoxib results in suppression of c-Kit and erythropoietin receptor (Epo-R) phosphorylation resulting in apoptosis, likely through decreased levels of survival factors. However, upon overexpression of c-Kit alone in these cells a significant increase in survival and twofold increase in proliferation in the presence of celecoxib were observed (P < 0.05). Finally, since responsiveness of our murine erythroleukemia cell lines to celecoxib is above the reported physiologically achievable levels in vivo, we have provided in vitro evidence to suggest that reduced sensitivity of erythroleukemic cells to lower doses of celecoxib may be a consequence of the loss of wild-type p53. These findings are pivotal in addressing potential discrepancies associated with sensitivity of murine erythroleukemic cells to celecoxib in vitro versus in vivo.

Treatment and prevention of necrotizing enterocolitis.

Necrotizing enterocolitis (NEC) is the most common serious, acquired gastrointestinal disorder in the newborn infant. Although many variables are associated with development of NEC, only prematurity has been consistently identified in case-controlled studies. Traditionally, the diving seal reflex has been invoked as the mechanism responsible for ischaemic injury and necrosis. Intestinal ischaemia is likely to be the final common pathway in NEC; however, it is due to the release of vasoconstricting substances, such as platelet activating factor, rather than perinatal asphyxia. Bacteria and/or bacterial toxins are likely to have a key role in the pathogenesis of NEC by fostering production of inflammatory mediators. The role of feeding practices in the pathogenesis of NEC remains controversial. Treatment of infants with NEC generally includes a regimen of bowel rest, gastric decompression, systemic antibiotics and parenteral nutrition. Infants with perforation are generally operated upon; however, there has been recent interest in primary peritoneal drainage as an alternative. Prevention of NEC still remains elusive. Avoidance of preterm birth, use of antenatal steroids and breast-milk feeding are practices that offer the greatest potential benefits. Use of any other strategy should await further trials.

Ethnic-difference markers for use in mapping by admixture linkage disequilibrium.

Mapping by admixture linkage disequilibrium (MALD) is a potentially powerful technique for the mapping of complex genetic diseases. The practical requirements of this method include (a) a set of markers spanning the genome that have large allele-frequency differences between the parental ethnicities contributing to the admixed population and (b) an understanding of the extent of admixture in the study population. To this end, a DNA-pooling technique was used to screen microsatellite and diallelic insertion/deletion markers for allele-frequency differences between putative representatives of the parental populations of the admixed Mexican American (MA) and African American (AA) populations. Markers with promising pooled differences were then confirmed by individual genotyping in both the parental and admixed populations. For the MA population, screening of >600 markers identified 151 ethnic-difference markers (EDMs) with delta>0.30 (where delta is the absolute value of each allele-frequency difference between two populations, summed over all marker alleles and divided by two) that are likely to be useful for MALD analysis. For the AA population, analysis of >400 markers identified 97 EDMs. In addition, individual genotyping of these markers in Pima Amerindians, Yavapai Amerindians, European American (EA) individuals, Africans from Zimbabwe, MA individuals, and AA individuals, as well as comparison to the CEPH genotyping set, suggests that the differences between subpopulations of an ethnicity are small for many markers with large interethnic differences. Estimates of admixture that are based on individual genotyping of these markers are consistent with a 60% EA:40% Amerindian contribution to MA populations and with a 20% EA:80% African contribution to AA populations. Taken together, these data suggest that EDMs with large interpopulation and small intrapopulation differences can be readily identified for MALD studies in both AA and MA populations.