Immortalized cell lines for real-time analysis of circadian pacemaker and peripheral oscillator properties

In the mammalian circadian system, cell‐autonomous clocks in the suprachiasmatic nuclei (SCN) are distinguished from those in other brain regions and peripheral tissues by the capacity to generate coordinated rhythms and drive oscillations in other cells. To further establish in vitro models for distinguishing the functional properties of SCN and peripheral oscillators, we developed immortalized cell lines derived from fibroblasts and the SCN anlage of mPer2 ^Luc knockin mice. Circadian rhythms in luminescence driven by the mPER2::LUC fusion protein were observed in cultures of mPer2 ^Luc SCN cells and in serum‐shocked or SCN2.2‐co‐cultured mPer2 ^Luc fibroblasts. SCN mPer2 ^Luc cells generated self‐sustained circadian oscillations that persisted for at least four cycles with periodicities of ≈24 h. Immortalized fibroblasts only showed circadian rhythms of mPER2::LUC expression in response to serum shock or when co‐cultured with SCN2.2 cells. Circadian oscillations of luminescence in mPer2 ^Luc fibroblasts decayed after 3–4 cycles in serum‐shocked cultures but robustly persisted for 6–7 cycles in the presence of SCN2.2 cells. In the co‐culture model, the circadian behavior of mPer2 ^Luc fibroblasts was dependent on the integrity of the molecular clockworks in co‐cultured SCN cells as persistent rhythmicity was not observed in the presence of immortalized SCN cells derived from mice with targeted disruption of Per1 and Per2 (Per1^ldc/Per2 ^ldc). Because immortalized mPer2 ^Luc SCN cells and fibroblasts retain their indigenous circadian properties, these in vitro models will be valuable for real‐time comparisons of clock gene rhythms in SCN and peripheral oscillators and identifying the diffusible signals that mediate the distinctive pacemaking function of the SCN.     

Prevalence of BRCA1 and BRCA2 mutations in Ashkenazi Jewish families with breast and pancreatic cancer

BACKGROUND:

Germline mutations in the BRCA2 cancer susceptibility gene are associated with an increased risk of pancreatic cancer (PC). Breast‐pancreas cancer families with BRCA1 mutations have also been observed. The influence of a family history (FH) of PC on BRCA mutation prevalence in patients with breast cancer (BC) is unknown.

METHODS:

A clinical database review (2000‐2009) identified 211 Ashkenazi Jewish (AJ) BC probands who 1) underwent BRCA1/2 mutation analysis by full gene sequencing or directed testing for Ashkenazi founder mutations (BRCA1: 185delAG and 5382insC; BRCA2: 6174delT) and 2) had a FH of PC in a first‐, second‐, or third‐degree relative. For each proband, the pretest probability of identifying a BRCA1/2 mutation was estimated using the Myriad II model. The observed‐to‐expected (O:E) mutation prevalence was calculated for the entire group.

RESULTS:

Of the 211 AJ BC probands with a FH of PC, 30 (14.2%) harbored a BRCA mutation. Fourteen (47%) of the mutations were in BRCA1 and 16 (53%) were in BRCA2. Patients diagnosed with BC at age ≤ 50 years were found to have a higher BRCA1/2 mutation prevalence than probands with BC who were diagnosed at age > 50 years (21.1% vs 6.9%; P = .003). In patients with a first‐, second‐, or third‐degree relative with PC, mutation prevalences were 15.4%, 15.3%, and 8.6%, respectively (P = .58). In the overall group, the observed BRCA1/2 mutation prevalence was 14.2% versus an expected prevalence of 11.8% (O:E ratio, 1.21; P = .15).

CONCLUSIONS:

BRCA1 and BRCA2 mutations are observed with nearly equal distribution in AJ breast‐pancreas cancer families, suggesting that both genes are associated with PC risk. In this population, a FH of PC was found to have a limited effect on mutation prevalence. Cancer 2011;. © 2011 American Cancer Society.     

The role of molecular analyses in the era of personalized therapy for advanced NSCLC

Platinum-based doublet chemotherapy is the traditional treatment of choice for advanced non-small cell lung cancer (NSCLC); however, the efficacy of these regimens has reached a plateau. Increasing evidence demonstrates that patients with sensitizing mutations in the epidermal growth factor receptor (EGFR) experience improved progression-free survival and response rates with first-line gefitinib or erlotinib therapy relative to traditional platinum-based chemotherapy, while patients with EGFR-mutation negative tumors gain greater benefit from platinum-based chemotherapy. These results highlight the importance of molecular testing prior to the initiation of first-line therapy for advanced NSCLC. Routine molecular testing of tumor samples represents an important paradigm shift in NSCLC therapy and would allow for individualized therapy in specific subsets of patients. As these and other advances in personalized treatment are integrated into everyday clinical practice, pulmonologists will play a vital role in ensuring that tumor samples of adequate quality and quantity are collected in order to perform appropriate molecular analyses to guide treatment decisions. This article provides an overview of clinical trial data supporting molecular analysis of NSCLC, describes specimen acquisition and testing methods currently in use, and discusses future directions of personalized therapy for patients with NSCLC.     

The relationship between body mass index and unintended pregnancy: results from the 2002 National Survey of Family Growth

BACKGROUND: The study was conducted to characterize the relationship between body mass index (BMI) and unintended pregnancy, contraceptive use patterns, and perceived fertility. METHODS: This study employed a cross-sectional, nationally representative database (2002 National Survey of Family Growth). Unintended pregnancy was compared among BMI groups [normal (<25 m/kg(2)), overweight (25-30 m/kg(2)) and obese (>30 m/kg(2))]. Analyses also evaluated the association between demographic, socioeconomic, behavioral and health-related variables and BMI. Multiple logistic regression with adjustment for sampling design was used to measure associations of interest. RESULTS: BMI data were available from 6690 nonpregnant women. Of these, 3600 (53.6%) were normal weight, 1643 (25%) were overweight and 1447 (21.4%) were obese. Compared to women with normal BMIs, the risk of unintended pregnancy in the last 5 years did not differ among overweight [adjusted OR 0.95 (95% CI 0.77-1.17)] or obese [adjusted OR 0.87 (95% CI 0.70-1.09)] women. There were no differences in contraceptive use patterns or perceived fertility among BMI groups. CONCLUSION: Data from the 2002 NSFG do not support an association between obesity and unintended pregnancy.     

The relation between neighborhood built environment and walking activity among older adults

The association of neighborhood built environment with walking activity has received growing attention, although most studies have relied upon subjective measures of the built environment and few have examined the relation between built environment and walking among older adults. This 2001 study examined the relation between objectively measured characteristics of the local neighborhood and walking activity among a sample of 546 community-dwelling older adults in Portland, Oregon. A geographic information system was used to derive measures of the built environment within a quarter-mile (0.4 km) and half-mile (0.8 km) radius around each participant's residence. Multilevel regression analysis was used to examine the association of built environment with walking behavior. No association between built environment and the likelihood of walking or not walking was observed in this cohort of older adults. However, among those participants who reported some degree of walking activity, average time spent walking per week was significantly associated with amount of automobile traffic and number of commercial establishments in their local neighborhood. These findings suggest that built environment may not play a significant role in whether older adults walk, but, among those who do walk, it is associated with increased levels of activity.     

Relationship between human chorionic gonadotropin serum levels and the risk of ovarian hyperstimulation syndrome

The object of this retrospective cohort study was to determine if hCG levels correlate with ovarian hyperstimulation syndrome (OHSS) risk after adjustment for other risk factors during in vitro fertilization (IVF). We measured serum hCG approximately 12?h after hCG trigger in women undergoing 406 cycles of controlled ovarian hyperstimulation for IVF between June 2006 and December 2009. Serum hCG levels were measured 12?h after trigger. Bivariate logistic regression was used to assess the association between patient and cycle characteristics and OHSS. In our series, mild to moderate OHSS occurred in 9% (38/406), and severe OHSS diagnosed in 1.5% (6/406) of IVF cycles. OHSS risk was increased in younger women (<30 years old: adjusted odds ratio: aOR 2.46, 95% confidence interval: CI 1.14–5.34), increased number of oocytes (11–20: aOR 6.79, 95% CI 1.97–23.40; >20: aOR 17.55, 95% CI 4.84–63.70), and increase E₂ levels (≥3,000?pg/mL: aOR 2.59, 95% CI 1.33–5.05), but was unrelated to hCG level (100–200?IU/L: aOR 1.53, 95% CI 0.60–3.91; ≥200?IU/L: aOR 1.42 95% CI 0.48–4.20). These results indicate that OHSS risk during IVF is unrelated to serum hCG level measured approximately 12?h after trigger.     

Evidence based surgical management of endometriosis

The management approach to patients with pelvic endometriosis is multidimensional. One must consider several factors such as patient’s age, parity, extent of the disease, and menopausal status when planning treatment strategies. The main goals of therapy are targeted at symptom control and achieving fertility in women who so desire. Medical and/or surgical therapies can be considered in these patients. Individualized patient care is essential for the success of treatment. In this review, we focus our discussion on surgical approach strategies and the management of endometriosis with an emphasis on pain and fertility outcomes.