Sex differences in ventricular-vascular coupling following endurance training

Introduction

Ventricular and vascular coupling is defined as the ratio of arterial elastance (Ea) to ventricular elastance (Elv) and describes the interaction between the heart and arterial system. There are sex differences in both arterial and ventricular function in response to both acute exercise and aerobic exercise training.

Purpose

To examine the effects of aerobic exercise training on elastances and the coupling ratio in young adult men and women. We hypothesized a reduction in the coupling ratio in both sexes due to a decrease in Ea that would be more pronounced in men and an increase in Elv that would be larger in women.

Methods

Fifty-three healthy, young adults completed the study. Central pulse wave velocity and heart volumes were measured before and after an 8-week aerobic training intervention. Elastances were calculated as Ea = end-systolic pressure/stroke volume and Elv = end-systolic pressure/end-systolic volume and indexed to body surface area.

Results

After the intervention, women augmented indexed and un-indexed Elv from 2.09 ± 0.61 to 2.52 ± 0.80 mmHg/ml, p < 0.05, and reduced the coupling ratio from 0.72 ± 18 to 0.62 ± 15, p < 0.05, while men maintained their pre-training ratio (from 0.66 ± 0.20 to 0.74 ± 0.21, p > 0.05). Women also reduced end-systolic pressure (from 91 ± 10 to 87 ± 10 mmHg), and both groups reduced central pulse wave velocity (from 6.0 ± 1.0 to 5.6 ± 0.6 m/s, p < 0.05).

Conclusion

We conclude that after 8 weeks of aerobic training, only women reduced their coupling ratio due to an increase in Elv. This suggests that aerobic exercise training elicits sex-dependent changes in the coupling ratio in young, healthy individuals.

The impact of a BRCA2 mutation on mortality from screen-detected prostate cancer

Background:

Men with a BRCA2 mutation face an increased risk of prostate cancer. These cancers tend to have an aggressive nature and it has not yet been demonstrated that regular screening of BRCA2 carriers is associated with improved survival.

Methods:

We identified 4187 men who underwent a prostate cancer biopsy for an elevated PSA or an abnormal digital rectal examination between 1998 and 2010. We screened the BRCA2 gene in its entirety for mutations and we followed the men for death from prostate cancer until December 2012.

Results:

The 12-year prostate cancer-specific survival rate was 94.3% for men without a BRCA2 mutation and was 61.8% for men with a mutation (P<10⁻⁴; log-rank test).

Conclusions:

The survival of men with screen-detected prostate cancer and a BRCA2 mutation is much poorer than expected.

Magnetic resonance imaging and dual energy X-ray absorptiometry of the lumbar spine in professional wrestlers and untrained men

The aim of this study was to examine the relation between bone marrow adipose tissue (BMAT) and bone mineral density (BMD) of lumbar spine in male professional wrestlers and healthy untrained men. A total of 14 wrestlers (22.9±3.4 years) and 11 controls (24.4±1.6 years) were studied cross-sectionally. Body composition and BMD were measured by dual-energy X-ray absorptiometry. Magnetic resonance imaging of the lumbar spine was examined in a sagittal T1-weighted (T1-w) spin-echo (SE) sequence. The averaged bone marrow signal intensity (SI) of L2-L4 was related to the signal of an adjacent nondegenerative disk. Mean SI of T1-w SE in wrestlers was lower than controls (P=0.001), indicating L2-L4 BMAT in wrestlers was lower compared to controls. L2-L4 BMD in wrestlers was higher than controls (P<0.001). In the total subject population, L2-L4 BMD was inversely correlated with mean SI of T1-w SE (r=-0.62, P=0.001). This association remained strong after adjusting for body mass and whole lean mass, but became weaker after adjusting for whole body or trunk fat percentage. The inverse relationship between BMAT and BMD was confirmed in this relatively small subject sample with narrow age range, which implies that exercise training is an important determinant of this association.

Factors associated with breast cancer mortality after local recurrence

PURPOSE

We aimed to identify risk factors for mortality after local recurrence in women treated for invasive breast cancer with breast-conserving surgery.

EXPERIMENTAL DESIGN

Our prospective cohort study included 267 women who were treated with breast-conserving surgery at Women's College Hospital from 1987 to 1997 and who later developed local recurrence. Clinical information and tumour receptor status were abstracted from medical records and pathology reports. Patients were followed from the date of local recurrence until death or last follow-up. Survival analysis used a Cox proportional hazards model.

RESULTS

Among the 267 women with a local recurrence, 97 (36.3%) died of breast cancer within 10 years (on average 2.6 years after the local recurrence). The actuarial risk of death was 46.1% at 10 years from recurrence. In a multivariable model, predictors of death included short time from diagnosis to recurrence [hazard ratio (hr) for <5 years compared with ≥10 years: 3.40; 95% confidence interval (ci): 1.04 to 11.1; p = 0.04], progesterone receptor positivity (hr: 0.35; 95% ci: 0.23 to 0.54; p < 0.001), lymph node positivity (hr: 2.1; 95% ci: 1.4 to 3.3; p = 0.001), and age at local recurrence (hr for age >45 compared with age ≤45 years: 0.61; 95% ci: 0.38 to 0.95; p = 0.03).

CONCLUSIONS

The risk of death after local recurrence varies widely. Risk factors for death after local recurrence include node positivity, progesterone receptor negativity, young age at recurrence, and short time from diagnosis to recurrence.

Breaking bonds in male prairie vole: long-term effects on emotional and social behavior, physiology, and neurochemistry

Social relationships are essential for many fundamental aspects of life while bond disruption can be detrimental to mental and physical health. Male prairie voles form enduring social bonds with their female partners, allowing the evaluation of partner loss on behavior, physiology, and neurochemistry. Males were evaluated for partner preference formation induced by 24h of mating, and half were separated from their partner for 4 wk. In Experiment 1, partner loss significantly increased anxiety-like behaviors in the elevated plus maze and light-dark box tests and marginally increased depressive-like behaviors in the forced swim test. In addition, while intruder-directed aggression is common in pair bonded prairie voles, separated males were affiliative and lacked aggression toward an unfamiliar female and an intruding male conspecific. Partner loss increased the density of oxytocin-immunoreactivity (-ir), vasopressin-ir, and corticotrophin-releasing hormone-ir cells in the paraventricular nucleus of the hypothalamus and oxytocin-ir cells in the supraoptic nucleus. Tyrosine hydroxylase-ir was not affected. In Experiment 2, partner preference was observed after 2 wk of partner loss but eliminated after 4 wk partner loss. Body weight gain and plasma corticosterone concentrations were elevated throughout the 4 wk. No effects were observed for plasma oxytocin or vasopressin. Together, partner loss elicits anxiety-like and depression-like behaviors, disrupts bond-related behaviors, and alters neuropeptide systems that regulate such behaviors. Thus, partner loss in male prairie voles may provide a model to better understand the behavior, pathology, and neurobiology underlying partner loss and grief.

A prior diagnosis of breast cancer is a risk factor for breast cancer in BRCA1 and BRCA2 carriers

BACKGROUND

The risk of breast cancer in carriers of BRCA1 and BRCA2 mutations is influenced by factors other than the genetic mutation itself. Modifying factors include a woman's reproductive history and family history of cancer. Risk factors are more likely to be present in women with breast cancer than in women without breast cancer, and therefore the risk of cancer in the two breasts should not be independent. It is not clear to what extent modifying factors influence the risk of a first primary or a contralateral breast cancer in BRCA carriers.

METHODS

We conducted a matched case-control study of breast cancer among 3920 BRCA1 or BRCA2 mutation carriers. We asked whether a past history of breast cancer in the contralateral breast was a risk factor for breast cancer.

RESULTS

After adjustment for age, country of residence, and cancer treatment, a previous cancer of the right breast was found to be a significant risk factor for cancer of the left breast among BRCA1 or BRCA2 carriers (relative risk: 2.1; 95% confidence interval: 1.4 to 3.0; p < 0.0001).

CONCLUSIONS

In a woman with a BRCA1 or BRCA2 mutation who is diagnosed with breast cancer, the risk of cancer in the contralateral breast depends on the first diagnosis. That observation supports the hypothesis that there are important genetic or non-genetic modifiers of cancer risk in BRCA carriers. Discovering risk modifiers might lead to greater personalization of risk assessment and management recommendations for BRCA-positive patients.

Breaking bonds in male prairie vole: long-term effects on emotional and social behavior, physiology, and neurochemistry

Social relationships are essential for many fundamental aspects of life while bond disruption can be detrimental to mental and physical health. Male prairie voles form enduring social bonds with their female partners, allowing the evaluation of partner loss on behavior, physiology, and neurochemistry. Males were evaluated for partner preference formation induced by 24h of mating, and half were separated from their partner for 4 wk. In Experiment 1, partner loss significantly increased anxiety-like behaviors in the elevated plus maze and light-dark box tests and marginally increased depressive-like behaviors in the forced swim test. In addition, while intruder-directed aggression is common in pair bonded prairie voles, separated males were affiliative and lacked aggression toward an unfamiliar female and an intruding male conspecific. Partner loss increased the density of oxytocin-immunoreactivity (-ir), vasopressin-ir, and corticotrophin-releasing hormone-ir cells in the paraventricular nucleus of the hypothalamus and oxytocin-ir cells in the supraoptic nucleus. Tyrosine hydroxylase-ir was not affected. In Experiment 2, partner preference was observed after 2 wk of partner loss but eliminated after 4 wk partner loss. Body weight gain and plasma corticosterone concentrations were elevated throughout the 4 wk. No effects were observed for plasma oxytocin or vasopressin. Together, partner loss elicits anxiety-like and depression-like behaviors, disrupts bond-related behaviors, and alters neuropeptide systems that regulate such behaviors. Thus, partner loss in male prairie voles may provide a model to better understand the behavior, pathology, and neurobiology underlying partner loss and grief.

Real-world comparison of health care utilization between duloxetine and pregabalin initiators with fibromyalgia

Objectives

To compare health care utilization of duloxetine initiators and pregabalin initiators among fibromyalgia patients in a real-world setting.

Methods

A retrospective cohort study was conducted based on a US national commercial health claims database (2006–2009). Fibromyalgia patients who initiated duloxetine or pregabalin in 2008, aged 18–64 years, and who maintained continuous health insurance coverage 1 year before and 1 year after initiation were assigned to duloxetine or pregabalin cohorts on the basis of their initiated agent. Patients who had pill coverage of the agents over the course of 90 days preceding the initiation were excluded. The two comparative cohorts were constructed using propensity score greedy match methods. Descriptive analysis and paired t-test were performed to compare health care utilization rates in the postinitiation year and the changes of these rates from the preinitiation year to the postinitiation year.

Results

Both matched cohorts (n=1,265 pairs) had a similar mean initiation age (49–50 years), percentage of women (87%–88%), and prevalence of baseline comorbid conditions (neuropathic pain other than diabetic peripheral neuropathic pain, low back pain, cardiovascular disease, hypertension, headache or migraine, and osteoarthritis). In the preinitiation year, both cohorts had similar inpatient, outpatient, and medication utilization rates (inpatient, 15.7%–16.1%; outpatient, 100.0%; medication, 97.9%–98.7%). The utilization rates diverged in the postinitiation year, with the pregabalin cohort using more fibromyalgia-related inpatient care (3.2% versus 2.2%; P<0.05), any inpatient care (19.3% versus 16.8%; P<0.05), and fibromyalgia-related outpatient care (62.1% versus 51.8%; P<0.05). From the preinitiation period to the postinitiation period, the duloxetine cohort experienced decreases in certain utilization rates, whereas the pregabalin cohort had increases (percentage of patients with a fibromyalgia-related admission, −1.2% versus 0.4% [P<0.01]; number of fibromyalgia-related outpatient claims, −1.7 versus 4.7 [P<0.01]).

Conclusion

Fibromyalgia patients initiating pregabalin tended to consume more fibromyalgia-related inpatient and outpatient care in the first postinitiation year, whereas fibromyalgia patients initiating duloxetine tended to have lower utilization rates of fibromyalgia-related inpatient care in the postinitiation year than in the preinitiation year.

Expression and significance of glucosylceramide synthase in colorectal carcinoma tissues

OBJECTIVE

To investigate the impression of glucosylceramide synthase (GCS) in colorectal carcinoma tissues.

MATERIALS AND METHODS

Immunohistochemical method was used to detect the expression of GCS in 188 cases of colorectal carcinoma tissues and 80 cases of non-cancerous colorectal tissues. The expression of GCS and the relation with age, gender, tumor location, Tumor stage, differentiation, lymph node metastasis were analyzed. Thus, we further discussed whether to accept neoadjuvant chemotherapy can affect the expression of GCS.

RESULTS

GCS was overexpressed in colorectal carcinoma tissues compared with non-cancerous colorectal tissues; the expression of GCS was associated with lymph node metastasis, but not associated with age, gender, tumor location, differentiation and Tumor stage. What's more, the positive expression rate of GCS in patients who receiving neoadjuvant chemotherapy was higher than that in untreated patients.

CONCLUSIONS

GCS was upregulated in colorectal carcinoma tissues. It might not only play an important role in controlling the generation and progression of colorectal carcinoma, but also be a factor of MDR.

CpG methylation of dmrt1 and cyp19a promoters in relation to their sexual dimorphic expression in the Japanese flounder Paralichthys olivaceus

To better understand the effects of DNA methylation on the expression patterns of dmrt1 (Doublesex and Mab-3-related transcription factor 1) and cyp19a (Cytochrome P450 19a) in the Japanese flounder Paralichthys olivaceus, quantitative expressions, cellular distributions and cytosine-p-guanine (CpG) methylation patterns of these two genes in the gonads were analysed. The results showed that P. olivaceus dmrt1 expression was 70 times higher in the testis than in the ovary (P < 0·05). Its mRNA was detected clearly in spermatocytes and Sertoli cells of the testis, but weakly in the ovary. Paralichthys olivaceus cyp19a expression was 40 times higher in the ovary than in the testis (P < 0·01). Its mRNA was detected clearly in follicular cells of the ovary, but weakly in spermatocytes of the testis. The dmrt1 promoter CpGs were not methylated in the testis, whereas 57·69% were methylated in the ovary. For the cyp19a promoter CpGs, 97·5% were methylated in the testis and 73·33% were methylated in the ovary. These findings demonstrate that P. olivaceus dmrt1 and cyp19a are sex-related genes with sexual dimorphic expression, CpG methylation levels of the two genes are consistent with their expression quantities, and this epigenetic modification can influence the differential expression of genes in the gonads of P. olivaceus.

NF-κB mediated miR-21 regulation in cardiomyocytes apoptosis under oxidative stress

Oxidative stress, defined as an excess production of reactive oxygen species (ROS), is shown to play an important role in the pathophysiology of cardiac remodeling including cell death and contractile dysfunction. Therefore, the balance between ROS production and removal of excess ROS is essential in maintaining the redox state and homeostasis balance in the cell. The increased ROS further activates nuclear factor-κB (NF-κB), a redox-sensitive transcription factor and promotes cell death. Recently, microRNAs (miRNAs) have been identified as critical regulators of various pathophysiological processes of cardiac remodeling; however, NF-κB-mediated miRNA's role in cardiomyocytes under oxidative stress remains undetermined. The miR-21 has been implicated in diverse cardiac remodeling; but, NF-κB-mediated miR-21 modulation in oxidative stress is currently unknown. Neonatal cardiomyocytes were transfected with IκBα mutant, miR-21 mimetic, and inhibitors separately, and were challenged with H2O2. The target gene, programmed cell death 4 (PDCD4), ROS activity, and NF-κB translocation were analyzed. Our results indicated that NF-κB positively regulated miR-21 expression under oxidative stress, and PDCD4 was a direct target for miR-21. NF-κB further regulated the expression of PDCD4 in H2O2-induced oxidative stress. Moreover, H2O2-induced ROS activity and cardiomyocytes apoptosis were partly protected by overexpression of miR-21 and displayed an important role in ROS-mediated cardiomyocytes injury. We evaluated a critical role of NF-κB-mediated miR-21 modulation in H2O2-induced oxidative stress in cardiomyocytes by targeting PDCD4. Our data may provide a new insight of miR-21's role in cardiac diseases primarily mediated by ROS.

Evidence for inbreeding depression in the tree Robinia pseudoacacia L. (Fabaceae)

The magnitude of inbreeding depression within populations is important for the evolution and maintenance of mixed mating systems. However, data are sparse on the magnitude of inbreeding depression in Robinia pseudoacacia. In this study, we compared differences in the mature seed set per fruit, seed mass, germination success, and seedling growth between self- and cross-pollination treatments and estimated the inbreeding depression at 3 stages: seed maturation, seedling emergence, and seedling growth at 10 and 20 weeks. We found that progenies resulting from cross-pollination treatments showed significantly higher fitness than progenies resulting from self-pollination, causing high levels of inbreeding depression. Inbreeding depression was not uniformly manifested, however, over the 3 stages. Inbreeding depression was the greatest between fertilization and seed maturation stage (δ = 0.5419), and the seedling emergence (0.3654) stage was second. No significant differences in seedling growth were observed between selfed and crossed progenies. The cumulative inbreeding depression (δ) across all 3 stages averaged 0.7452. Inbreeding depression may promote outcrossing in R. pseudoacacia by acting as a post-pollination barrier to selfing. The large difference in the seed set between self- and cross-pollination that we detected indicated that inbreeding depression would probably be a reasonable explanation for the high abortion and low seed set in R. pseudoacacia.

Development of electron cyclotron emission imaging system on the HL-2A tokamak

A 2D electron cyclotron emission imaging (ECEI) system has been developed for measurement of electron temperature fluctuations in the HL-2A tokamak. It is comprised of a front-end 24 channel heterodyne imaging array with a tunable RF range spanning 75-110 GHz, and a set of back-end ECEI electronics that together generate 24 × 8 = 192 channel images of the 2nd harmonic X-mode electron cyclotron emission from the HL-2A plasma. The simulated performance of the local oscillator (LO) optics and radio frequency (RF) optics is presented, together with the laboratory characterization results. The Gaussian beams from the LO optics are observed to properly cover the entire detector array. The ECE signals from the plasma are mixed with the LO signal in the array box, then delivered to the electronics system by low-loss microwave cables, and finally to the digitizers. The ECEI system can achieve temporal resolutions of ~μs, and spatial resolutions of 1 cm (radially) and 2 cm (poloidally).

Are two-centimeter breast cancers large or small?

BACKGROUND

Node-negative breast cancers from 2 cm to 5 cm in size are classified as stage ii, and smaller cancers, as stage i. We sought to determine if the prognosis of women with a breast cancer exactly 2 cm in size more closely resembles that of women with a stage i or a stage ii breast cancer.

METHODS

Using a cohort of 4265 young women with breast cancer, we compared the 10-year breast cancer mortality rates for women who had a tumour 0.1-1.9 cm, exactly 2.0 cm, and 2.1-2.9 cm.

RESULTS

In the first 3 years after diagnosis, the survival pattern of women with a 2.0-cm breast cancer was nearly identical to that of women with a larger cancer (2.1-3.0 cm). From year 3 to year 10, the relative survival of women with a 2.0-cm breast cancer was improved and nearly identical to that of women with a smaller cancer. The 10-year survival rate was 89.3% for women with tumours less than 20 mm, 86.1% for women with tumours equal to 20 mm, and 81.2% for women with 21-mm to 29-mm tumours.

CONCLUSIONS

For young women with small breast cancers, the relative mortality from breast cancer is dynamic with increasing tumour size and varies with time from diagnosis.