Do Different Semi-Occluded Voice Exercises Affect Vocal Fold Adduction Differently in Subjects Diagnosed with Hyperfunctional Dysphonia?

OBJECTIVE

To observe the possible differential effects of 8 different semi-occluded vocal tract exercises on glottal contact quotient (CQ) as a measure of vocal fold impact stress.

PATIENTS AND METHODS

Eighty participants were divided into two groups: an experimental group with hyperfunctional dysphonia and a control group of vocally healthy subjects. The participants were recorded before, during and after the exercises. Electroglottographic samples were analyzed to obtain CQ.

RESULTS

For the experimental group, all exercises, except lip trills and tongue trills, had an overall significant effect when conditions before, during and after the exercises were compared. The CQ presented differently across the 8 semi-occluded postures during exercise for both groups. For the experimental group, most exercises increased the CQ during practice. Only lip and tongue trills demonstrated lower CQ during exercise.

CONCLUSIONS

Different semi-occluded exercises differentially affect vocal fold adduction. Lip and tongue trills produced the lowest CQ. Therefore, they may be recommended for decreasing glottal adduction. A straw submerged 10 cm below the water surface presented the greatest CQ. A shallower depth led to a lower CQ, while deeper submersion produced a higher CQ.

Habitat complexity reduces parasitoid foraging efficiency, but does not prevent orientation towards learned host plant odours

It is well known that many parasitic wasps use herbivore-induced plant odours (HIPVs) to locate their inconspicuous host insects, and are often able to distinguish between slight differences in plant odour composition. However, few studies have examined parasitoid foraging behaviour under (semi-)field conditions. In nature, food plants of parasitoid hosts are often embedded in non-host-plant assemblages that confer both structural and chemical complexity. By releasing both naïve and experienced Cotesia glomerata females in outdoor tents, we studied how natural vegetation surrounding Pieris brassicae-infested Sinapis arvensis and Barbarea vulgaris plants influences their foraging efficiency as well as their ability to specifically orient towards the HIPVs of the host plant species on which they previously had a positive oviposition experience. Natural background vegetation reduced the host-encounter rate of naïve C. glomerata females by 47 %. While associative learning of host plant HIPVs 1 day prior to foraging caused a 28 % increase in the overall foraging efficiency of C. glomerata, it did not reduce the negative influence of natural background vegetation. At the same time, however, females foraging in natural vegetation attacked more host patches on host-plant species on which they previously had a positive oviposition experience. We conclude that, even though the presence of natural vegetation reduces the foraging efficiency of C. glomerata, it does not prevent experienced female wasps from specifically orienting towards the host-plant species from which they had learned the HIPVs.

Abstract 3336: The heterotypic interaction between CXCR7 and EGFR is an alternative proliferation mechanism in breast cancer

Introduction: CXCR7 is selectively over expressed in Breast Cancer (BrCa), suggesting its potential importance in BrCa development and function. CXCR7 is the latest CXC-chemokine receptor implicated in BrCa growth. Although it is endogenously over expressed in BrCa, the CXCR7 mechanism of tumor growth enhancement is still vaguely described. BrCa is a heterogeneous disease in several ways. An investigation of the interaction of CXCR7 with EGFR will help determine the relative contribution and consequence of such interaction in BrCa cell proliferation and progression.

Results: CXCR7 is expressed predominantly in Estrogen Receptor positive (ER+) BrCa cells, MCF7 and BT474, and was absent in common ER- BrCa cells. CXCR7 was expressed unevenly in normal breast and ER+ cancer tissues. Depletion of CXCR7 in BrCa cells by RNAi decreased cell proliferation and caused cell cycle arrest, with significant changes in cell cycle-associated proteins. Addition, depletion, and rescue of CXCR7-ligand, SDF-1a, had no significant effect on cell proliferation or phosphorylation of ERK1/2. Depletion of CXCR7 led to inhibition of EGF-mediated phosphorylation of EGFR at Tyrosine 1110 and ERK1/2 phosphorylation. We examined whether CXCR7 regulates BrCa proliferation through interaction with EGFR or by activating other potential targets of MAP-kinase activation and found that CXCR7 complexes with EGFR, as demonstrated by co-immunoprecipitation followed by immunoblotting and with proximity ligation assays, using the Duo-link fluorescence technique. Investigation of whether CXCR7-EGFR interaction is direct or indirect, led to test potential translocation of fluorescent β-Arrestin-2 from the plasma membrane to the cytoplasm. SDF-1a addition to MCF7 cells, over expressing β-Arrestin-2-EGFP, induced minimal movement of β-Arrestin-2-EGFP over a 30 min window, whereas EGF addition induced re-arrangement of β-Arrestin-2-EGFP localization. When CXCR7 was down-regulated by siRNA, the beta-ARR2-EGFP rearrangement was significantly reduced, suggesting this CXCR7-EGFR interaction is facilitated by β-Arrestin-2.

Conclusion: Our results demonstrate a heterotypic interaction between CXCR7 and EGFR in breast cancer independent of SDF-1a. Recent studies remind us that seventy percent of breast cancers are ER+ even at the metastatic stage, making the expression of CXCR7 clinically relevant. The innate heterogeneity of BrCa makes it clear that proliferation mechanisms change and may be altered during cancer progression, so that CXCR7 and other receptors may step in to support proliferation. These results demonstrate the important role of CXCR7 in breast cancer growth and progression.

Citation Format: Nicole Salazar, Daniel Muñoz, Rajendra K. Singh, Bal L. Lokeshwar. The heterotypic interaction between CXCR7 and EGFR is an alternative proliferation mechanism in breast cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3336. doi:10.1158/1538-7445.AM2014-3336

Acoustic markers to differentiate gender in prepubescent children's speaking and singing voice

OBJECTIVES

Investigation sought to determine whether there is any acoustic variable to objectively differentiate gender in children with normal voices.

METHODS

A total of 30 children, 15 boys and 15 girls, with perceptually normal voices were examined. They were between 7 and 10 years old (mean: 8.1, SD: 0.7 years). Subjects were required to perform the following phonatory tasks: (1) to phonate sustained vowels [a:], [i:], [u:], (2) to read a phonetically balanced text, and (3) to sing a song. Acoustic analysis included long-term average spectrum (LTAS), fundamental frequency (F0), speaking fundamental frequency (SFF), equivalent continuous sound level (Leq), linear predictive code (LPC) to obtain formant frequencies, perturbation measures, harmonic to noise ratio (HNR), and Cepstral peak prominence (CPP). Auditory perceptual analysis was performed by four blinded judges to determine gender.

RESULTS

No significant gender-related differences were found for most acoustic variables. Perceptual assessment showed good intra and inter rater reliability for gender. Cepstrum for [a:], alpha ratio in text, shimmer for [i:], F3 in [a:], and F3 in [i:], were the parameters that composed the multivariate logistic regression model to best differentiate male and female children's voices.

CONCLUSION

Since perceptual assessment reliably detected gender, it is likely that other acoustic markers (not evaluated in the present study) are able to make clearer gender differences. For example, gender-specific patterns of intonation may be a more accurate feature for differentiating gender in children's voices.

The chemokine receptor CXCR7 interacts with EGFR to promote breast cancer cell proliferation

Background

Recent advances have revealed a significant contribution of chemokines and their receptors in tumor growth, survival after chemotherapy, and organ-specific metastasis. The CXC chemokine receptor-7 (CXCR7) is the latest chemokine receptor implicated in cancer. Although over expressed in breast cancer cell lines and tumor tissues, its mechanism of action in breast cancer (BrCa) growth and metastasis is unclear. Studies in other cancers have implicated CXCR7 in cell proliferation, anti-apoptotic activity and cell-cell adhesion. The present study was initiated to examine the pattern of CXCR7 expression and its role in regulation of growth signaling in breast cancer.

Methods

The contribution of CXCR7 in BrCa cell proliferation was investigated in representative cell lines using real time quantitative PCR (q-PCR), proliferation assays, immunohistochemistry and immunoblotting. Phenotypic changes were examined after CXCR7 specific cDNA and siRNA transfection and expression levels were monitored by q-PCR. Further, the association of CXCR7 with epidermal growth factor receptor (EGFR) and modulation of its activity were investigated by western blotting, immunofluorescence, and in-situ proximity ligation assays in human BrCa cells and tissues.

Results

CXCR7 was expressed in both, estrogen receptor (ER) positive and negative BrCa cell lines. CXCR7 was also expressed unevenly in normal breast tissues and to a much higher extent in ER + cancer tissues. Depletion of CXCR7 in MCF7 BrCa cells by RNA interference decreased proliferation and caused cell cycle arrest. Further, proximity ligation assay (PLA) revealed colocalization of CXCR7 with EGFR in cancer tissues and cancer cell lines. CXCR7 depletion reduced levels of phospho-EGFR at Tyrosine1110 after EGF-stimulation and also reduced phosphorylation of ERK1/2, indicating a potentially direct impact on mitogenic signaling in MCF7 cells. Using siRNA to knockdown β-arrestin2 in cells with EGFR over expression we were able to nearly deplete the CXCR7-EGFR colocalization events, suggesting that β-arrestin2 acts as a scaffold to enhance CXCR7 dependent activation of EGFR after EGF stimulation.

Conclusions

These results demonstrate coupling of CXCR7 with EGFR to regulate proliferation of BrCa cells and suggest an important ligand-independent role of CXCR7 in BrCa growth. Thus, the CXCR7-EGFR axis is a promising target for breast cancer therapy.

Electronic supplementary material

The online version of this article (doi:10.1186/1476-4598-13-198) contains supplementary material, which is available to authorized users.

Targeting adenosine signaling to treatment of diabetic nephropathy

Diabetic nephropathy (DN) continues being the primary cause of chronic hemodialysis and terminal renal disease worldwide. At tissue levels the DN occurs with glomerulopathy affecting the integrity of the filtration barrier and with an extensive glomerular and tubule-interstitial fibrosis. Current available therapeutic approaches have only demonstrated a modest effect on progression of kidney injury. Therefore, more research concerning the pathomechanisms and possible interventions are needed. Interestingly, in the last years it has been documented that DN progresses with growing levels of the nucleoside adenosine. This finding increased the interest in the events controlling the extracellular levels of the nucleoside. While the metabolism of extracellular ATP and cyclic AMP are well recognized sources, evidences regarding the role of the equilibrative nucleoside transporters in controlling adenosine availability and promoting diabetic glomerulopathy have recently acquired a pivotal role. The physiological effects of nucleoside are mediated by the P1 family of adenosine receptors. It has been shown in vivo that the use of an antagonist of the A2B receptor subtype can block the most remarkable early alterations seen in diabetic glomerulopathy. Furthermore, using models of chronic kidney injury it was demonstrated that fibrosis can also be blocked using treatment with the antagonist of A2B receptor subtype. This review highlights these findings that correlate the activity of a low affinity adenosine receptor with an increase in the ligand availability in the pathological state. In addition, we discuss the possible therapeutic interventions of adenosine signaling with regards to DN treatment.

Regional systems of care demonstration project: Mission: Lifeline STEMI Systems Accelerator: design and methodology

ST-segment elevation myocardial infarction (STEMI) systems of care have been associated with significant improvement in use and timeliness of reperfusion. Consequently, national guidelines recommend that each community should develop a regional STEMI care system. However, significant barriers continue to impede widespread establishment of regional STEMI care systems in the United States. We designed the Regional Systems of Care Demonstration Project: Mission: Lifeline STEMI Systems Accelerator, a national educational outcome research study in collaboration with the American Heart Association, to comprehensively accelerate the implementation of STEMI care systems in 17 major metropolitan regions encompassing >1,500 emergency medical service agencies and 450 hospitals across the United States. The goals of the program are to identify regional gaps, barriers, and inefficiencies in STEMI care and to devise strategies to implement proven recommendations to enhance the quality and consistency of care. The study interventions, facilitated by national faculty with expertise in regional STEMI system organization in partnership with American Heart Association representatives, draw upon specific resources with proven past effectiveness in augmenting regional organization. These include bringing together leading regional health care providers and institutions to establish common commitment to STEMI care improvement, developing consensus-based standardized protocols in accordance with national professional guidelines to address local needs, and collecting and regularly reviewing regional data to identify areas for improvement. Interventions focus on each component of the reperfusion process: the emergency medical service, the emergency department, the catheterization laboratory, and inter-hospital transfer. The impact of regionalization of STEMI care on clinical outcomes will be evaluated.

Abstract C210: Atypical chemokine receptor 3/CXCR7 and EGFR interact to control breast cancer growth

Introduction: Breast cancer (BrCa) is a major burden for women in the US, ranking second in both incidence and cancer related deaths. Many studies comparing cancer vs. normal gene expression have identified CXCR7 as being preferentially expressed in several different cancer types, including breast cancer. CXCR7 is the latest CXC-chemokine receptor implicated in breast cancer growth. The chemokine receptor CXCR7 is an atypical G-protein coupled receptor, in that it does not bind G-proteins as GPCRs do. It is so atypical, that convention by HUGO has recently changed the name of CXCR7 to ACKR3, atypical chemokine receptor 3.

Methods: We used the database Oncomine to confirm the correlation of CXCR7 with breast cancer at both mRNA and tissue level. We also show functional expression of CXCR7 on relevant human breast cancer cell lines and tissue. To identify the mechanism of function of CXCR7 in BrCa we studied its interaction with EGFR and beta-arrestin2 (beta-ARR2), which are relevant partners important in the mitogenic growth cascade. We used a proximity ligation assay (PLA) to visualize CXCR7-EGFR co-localization both in cell culture and in human normal and breast cancer tissue. To visualize interaction with beta-ARR2, we used live cell confocal microscopy.

Results: CXCR7 was over-expressed in ER-α positive BrCa cells, compared to normal breast epithelial cells. ER-negative cells also expressed CXCR7, however, at lower levels. Depletion of CXCR7 in MCF-7 BrCa cells by RNAi decreased cell proliferation and caused cell cycle arrest. Since CXCR7 is an atypical G-protein coupled receptor where ligand activation does not elicit conventional intracellular signaling, we hypothesized that CXCR7 regulates BrCa proliferation through interaction with EGFR or activation of other potential targets of the MAP-kinase pathway. CXCR7 depletion reduced site-specific phosphorylation of EGFR at Tyrosine 1110 after EGF-stimulation. CXCR7 depletion also reduced phosphorylation of ERK-1/2, indicating a potentially direct interaction with mitogenic signaling in MCF-7 cells. We found EGFR and CXCR7 co-localize as demonstrated by confocal microscopy, with increased co-localization after EGF stimulation. To clarify whether CXCR7-EGFR interaction is direct or indirect, we analyzed the role beta-ARR2 plays in this transactivation. SDF1 addition to MCF7 cells over expressing beta-ARR2-EGFP induced minimal movement of beta-ARR2-EGFP over a 30 min window. EGF addition induced an obvious shift of beta-ARR2-EGFP localization. When CXCR7 was down-regulated by siRNA, there was decreased rearrangement of beta-ARR2-EGFP after EGF stimulation, suggesting this CXCR7-EGFR interaction is beta-ARR2 mediated.

Conclusion: These data demonstrate significant molecular interactions between two cell surface receptors that have high clinical significance. The impact of this work may potentially lead to better treatment strategies based on cell surface targets.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):C210.

Citation Format: Nicole Salazar, Daniel Muñoz, Bal L. Lokeshwar. Atypical chemokine receptor 3/CXCR7 and EGFR interact to control breast cancer growth. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr C210.

Predictors and dynamics of postpartum relapses in women with multiple sclerosis

Background:

Several studies have shown that pregnancy reduces multiple sclerosis (MS) relapses, which increase in the early postpartum period. Postpartum relapse risk has been predicted by pre-pregnancy disease activity in some studies.

Objective:

To re-examine effect of pregnancy on relapses using the large international MSBase Registry, examining predictors of early postpartum relapse.

Methods:

An observational case–control study was performed including pregnancies post-MS onset. Annualised relapse rate (ARR) and median Expanded Disability Status Scale (EDSS) scores were compared for the 24 months pre-conception, pregnancy and 24 months postpartum periods. Clustered logistic regression was used to investigate predictors of early postpartum relapses.

Results:

The study included 893 pregnancies in 674 females with MS. ARR (standard error) pre-pregnancy was 0.32 (0.02), which fell to 0.13 (0.03) in the third trimester and rose to 0.61 (0.06) in the first three months postpartum. Median EDSS remained unchanged. Pre-conception ARR and disease-modifying treatment (DMT) predicted early postpartum relapse in a multivariable model.

Conclusion:

Results confirm a favourable effect on relapses as pregnancy proceeds, and an early postpartum peak. Pre-conception DMT exposure and low ARR were independently protective against postpartum relapse. This novel finding could provide clinicians with a strategy to minimise postpartum relapse risk in women with MS planning pregnancy.

Laryngeal and pharyngeal activity during semioccluded vocal tract postures in subjects diagnosed with hyperfunctional dysphonia

High vertical laryngeal position (VLP), pharyngeal constriction, and laryngeal compression are common features associated with hyperfunctional voice disorders. The present study aimed to observe the effect on these variables of different semioccluded vocal tract postures in 20 subjects diagnosed with hyperfunctional dysphonia. During observation with flexible endoscope, each participant was asked to produce eight different semioccluded exercises: lip trills, hand-over-mouth technique, phonation into four different tubes, and tube phonation into water using two different depth levels. Participants were required to produce each exercise at three loudness levels: habitual, soft, and loud. To determine the VLP, anterior-to-posterior (A-P) compression, and pharyngeal width, a human evaluation test with three blinded laryngologists was conducted. Judges rated the three endoscopic variables using a five-point Likert scale. An intraclass correlation coefficient to assess intrarater and interrater agreement was performed. A multivariate linear regression model considering VLP, pharyngeal width, and A-P laryngeal compression as outcomes and phonatory tasks and intensity levels as predictive variables were carried out. Correlation analysis between variables was also conducted. Results indicate that all variables differ significantly. Therefore, VLP, A-P constriction, and pharyngeal width changed differently throughout the eight semioccluded postures. All semioccluded techniques produced a lower VLP, narrower aryepiglottic opening, and a wider pharynx than resting position. More prominent changes were obtained with a tube into the water and narrow tube into the air. VLP significantly correlated with pharyngeal width and A-P laryngeal compression. Moreover, pharyngeal width significantly correlated with A-P laryngeal compression.

Bypassing the Emergency Department and Time to Reperfusion in Patients With Prehospital ST-Segment–Elevation

Background—

Among patients identified prehospital with ST-segment–elevation myocardial infarction, emergency medical service transport from the field directly to the catheterization laboratory, thereby bypassing the emergency department (ED), may shorten time to reperfusion.

Methods and Results—

We studied 1687 patients identified prehospital with ST-segment–elevation myocardial infarction from the Reperfusion in Acute Myocardial Infarction in Carolina Emergency Departments (RACE) project, transported via emergency medical service directly to 21 North Carolina hospitals for primary percutaneous coronary intervention between July 2008 and December 2009. Treatment time intervals were compared between patients evaluated in the ED (ED evaluation) and those transported directly to the catheterization laboratory (ED bypass). Emergency medical service transported 1401 (83.0%) patients to the ED, whereas the ED was bypassed for 286 (17.0%) patients. Overall, first medical contact to device activation within 90 minutes was achieved in 913 (54.1%) patients. Among patients evaluated in the ED, median time (25th–75th percentiles) from ED arrival to catheterization laboratory arrival was 30 (20–41) minutes. First medical contact to device activation occurred faster (75 [59–93] versus 90 [76–109] minutes; P <0.001) and was more frequently achieved within 90 minutes (74.1% versus 50.1%; P <0.001) among ED bypass patients.

Conclusions—

Among patients identified prehospital with ST-segment–elevation myocardial infarction and transported directly to a percutaneous coronary intervention hospital, only 1 in 2 achieve device activation within 90 minutes. A median of 30 minutes is spent in the ED, contributing significantly to the failure to achieve timely reperfusion. The strategy to bypass the ED is used infrequently and represents a potential opportunity to improve reperfusion times.

Approaches to decongestion in patients with acute decompensated heart failure

Loop diuretics remain a mainstay in the pharmacologic treatment of acute decompensated heart failure (ADHF). Recent randomized trial results have challenged existing clinical dogma about the optimal manner of intravenous diuretic administration in hospitalized patients. The Diuretic Optimization Strategies Evaluation (DOSE) trial, while technically a neutral study, suggested some advantages of a high-dose diuretic strategy as compared with low dose administration without evidence of long term safety concerns. The DOSE study additionally showed no difference in efficacy or safety between continuous infusion or bolus diuretic therapy. Venovenous ultrafiltration (UF) holds promise as an alternative approach to volume removal in ADHF, but significant work remains in characterizing the relative risks and benefits of this technique, as well as the degree to which it can be broadly utilized. This review highlights current approaches and future directions in mitigating congestion and volume overload in the ADHF population, with a particular focus on novel diuretic dosing strategies and on the emerging role of UF.