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Patients with congenital long QT syndrome (LQTS) type 2 (LQT2) may develop arrhythmias during emotional stress, acoustic stimuli, or sleep. Women with LQT2 are more susceptible to fatal arrhythmias than are men.

The purpose of this study was to examine the effects of sleep on RR and QT intervals in patients with LQT1, in those with LQT2, and in controls and to test the hypothesis that there is a gene-specific effect of sleep on the QT interval in LQT2 that may be especially evident in women with LQT2.

Thirty-four subjects with genotyped LQTS and 18 healthy controls were studied. Among the 34 subjects with LQTS, 16 (10 women, age 32 +/- 3 years) had LQT1 and 18 (11 women, age 38 +/- 3 years) had LQT2. Subjects underwent standard polysomnography including ECG recordings. RR, QT, and QTc (Bazett and Fridericia formulas) were measured over recordings obtained during stable conditions during wakefulness, during stage 2 and stages 3-4 of non-rapid eye movement (NREM), and during rapid eye movement (REM) sleep.

LQT2 women showed a marked RR decrease and marked QT and QTc increase from NREM to REM sleep, changes that were not observed in either women or men with LQT1 or in men with LQT2.

Pronounced cardiac activation during REM and substantial QTc prolongation is noted in a sex- and gene-specific fashion among women with LQT2. REM-related changes in cardiac activation and ventricular repolarization may be implicated in sleep-related malignant arrhythmias in women with the LQT2 genotype.

We have previously shown a higher level of HIV-1 replication and gene expression in neonatal (cord) blood mononuclear cells (CBMC) compared with adult blood cells (PBMC), which could be due to differential expression of host factors. We performed the gene expression profile of CBMC and PBMC and found that 8013 genes were expressed at higher levels in CBMC than PBMC and 8028 genes in PBMC than CBMC, including 1181 and 1414 genes upregulated after HIV-1 infection in CBMC and PBMC, respectively. Several transcription factors (NF-kappaB, E2F, HAT-1, TFIIE, Cdk9, Cyclin T1), signal transducers (STAT3, STAT5A) and cytokines (IL-1beta, IL-6, IL-10) were upregulated in CBMC than PBMC, which are known to influence HIV-1 replication. In addition, a repressor of HIV-1 transcription, YY1, was down regulated in CBMC than PBMC and several matrix metalloproteinase (MMP-7, -12, -14) were significantly upregulated in HIV-1 infected CBMC than PBMC. Furthermore, we show that CBMC nuclear extracts interacted with a higher extent to HIV-1 LTR cis-acting sequences, including NF-kappaB, NFAT, AP1 and NF-IL6 compared with PBMC nuclear extracts and retroviral based short hairpin RNA (shRNA) for STAT3 and IL-6 down regulated their own and HIV-1 gene expression, signifying that these factors influenced differential HIV-1 gene expression in CBMC than PBMC.

Regulation of actin filament assembly is essential for efficient contractile activity in striated muscle. Leiomodin is an actin-binding protein and homolog of the pointed-end capping protein, tropomodulin. These proteins are structurally similar, sharing a common domain organization that includes two actin-binding sites. Leiomodin also contains a unique C-terminal extension that has a third actin-binding WH2 domain. Recently, the striated-muscle-specific isoform of leiomodin (Lmod2) was reported to be an actin nucleator in cardiomyocytes. Here, we have identified a function of Lmod2 in the regulation of thin filament lengths. We show that Lmod2 localizes to the pointed ends of thin filaments, where it competes for binding with tropomodulin-1 (Tmod1). Overexpression of Lmod2 results in loss of Tmod1 assembly and elongation of the thin filaments from their pointed ends. The Lmod2 WH2 domain is required for lengthening because its removal results in a molecule that caps the pointed ends similarly to Tmod1. Furthermore, Lmod2 transcripts are first detected in the heart after it has begun to beat, suggesting that the primary function of Lmod2 is to maintain thin filament lengths in the mature heart. Thus, Lmod2 antagonizes the function of Tmod1, and together, these molecules might fine-tune thin filament lengths.

The Krüppel-like transcription factors (KLF) are zinc finger proteins that activate and suppress target gene transcription. Although KLF factors have been implicated in regulating many developmental processes, a comprehensive gene expression analysis has not been reported. Here we present the chicken KLF gene family and expression during the first five days of embryonic development. Fourteen chicken KLF genes or expressed sequences have been previously identified. Through synteny analysis and cDNA mapping, we have identified the KLF9 gene and determined that the gene presently named KLF1 is the true ortholog of KLF17 in other species. In situ hybridization expression analyses show that in general KLFs are broadly expressed in multiple cell and tissue types. Expression of KLFs 3, 7, 8, and 9, is widespread at all stages examined. KLFs 2, 4, 5, 6, 10, 11, 15, and 17 show more restricted patterns that suggest multiple functions during early stages of embryonic development.

Arsenic is a naturally occurring metalloid and environmental contaminant. Arsenic exposure in drinking water is reported to cause cancer of the liver, kidneys, lung, bladder, and skin as well as birth defects, including neural tube, facial, and vasculogenic defects. The early embryonic period most sensitive to arsenic includes a variety of cellular processes. One key cellular process is epithelial-mesenchymal transition (EMT) where epithelial sheets develop into three-dimensional structures. An embryonic prototype of EMT is found in the atrioventricular (AV) canal of the developing heart, where endothelia differentiate to form heart valves. Effects of arsenic on this cellular process were examined by collagen gel invasion assay (EMT assay) using explanted AV canals from chicken embryo hearts. AV canals treated with 12.5-500 ppb arsenic showed a loss of mesenchyme at 12.5 ppb, and mesenchyme formation was completely inhibited at 500 ppb. Altered gene expression in arsenic-treated explants was investigated by microarray analysis. Genes whose expression was altered consistently at exposure levels of 10, 25, and 100 ppb were identified, and results showed that 25 ppb in vitro was particularly effective. Three hundred and eighty two genes were significantly altered at this exposure level. Cytoscape analysis of the microarray data using the chicken interactome identified four clusters of altered genes based on published relationships and pathways. This analysis identified cytoskeleton and cell adhesion-related genes whose disruption is consistent with an altered ability to undergo EMT. These studies show that EMT is sensitive to arsenic and that an interactome-based approach can be useful in identifying targets.

In situ hybridization is widely used to visualize transcribed sequences in embryos, tissues, and cells. For whole mount detection of mRNAs in embryos, hybridization with an antisense RNA probe is followed by visual or fluorescence detection of target mRNAs. A limitation of this approach is that a cDNA template of the target RNA must be obtained in order to generate the antisense RNA probe. Here we investigate the use of short (12-24 nucleotides) locked nucleic acid (LNA) containing DNA probes for whole mount in situ hybridization detection of mRNAs. Following extensive protocol optimization, we show that LNA probes can be used to localize several mRNAs of varying abundances in chicken embryos. LNA probes also detected alternatively spliced exons that are processed in a tissue specific manner. The use of LNA probes for whole mount in situ detection of mRNAs will enable in silico design and chemical synthesis and will expand the general use of in situ hybridization for studies of transcriptional regulation and alternative splicing.

A cell-penetrating, fluorescent protein substrate was developed to monitor intracellular protein kinase A (PKA) activity in cells without the need for cellular transfection. The PKA substrate (PKAS) was prepared with a 6xhistidine purification tag, an enhanced green fluorescent protein (EGFP) reporter, an HIV-TAT protein transduction domain for cellular translocation and a pentaphosphorylation motif specific for PKA. PKAS was expressed in Escherichia coli and purified by metal affinity chromatography. Incubation of PKAS in the extracellular media facilitated translocation into the intracellular milieu in HeLa cells, betaTC-3 cells and pancreatic islets with minimal toxicity in a time and concentration dependent manner. Upon cellular loading, glucose-dependent phosphorylation of PKAS was observed in both betaTC-3 cells and pancreatic islets via capillary zone electrophoresis. In pancreatic islets, maximal PKAS phosphorylation (83 +/- 6%) was observed at 12 mM glucose, whereas maximal PKAS phosphorylation (86 +/- 4%) in betaTC-3 cells was observed at 3 mM glucose indicating a left-shifted glucose sensitivity. Increased PKAS phosphorylation was observed in the presence of PKA stimulators forskolin and 8-Br-cAMP (33% and 16%, respectively), with corresponding decreases in PKAS phosphorylation observed in the presence of PKA inhibitors staurosporine and H-89 (40% and 54%, respectively).

Suspended planar lipid membranes (or black lipid membranes (BLMs)) are widely used for studying reconstituted ion channels, although they lack the chemical and mechanical stability needed for incorporation into high-throughput biosensors and biochips. Lipid polymerization enhances BLM stability but is incompatible with ion channel function when membrane fluidity is required. Here, we demonstrate the preparation of a highly stable BLM that retains significant fluidity by using a mixture of polymerizable and nonpolymerizable phospholipids. Alamethicin, a voltage-gated peptide channel for which membrane fluidity is required for activity, was reconstituted into mixed BLMs prepared using bis-dienoyl phosphatidylcholine (bis-DenPC) and diphytanoyl phosphatidylcholine (DPhPC). Polymerization yielded BLMs that retain the fluidity required for alamethicin activity yet are stable for several days as compared to a few hours prior to polymerization. Thus, these polymerized, binary composition BLMs feature both fluidity and long-term stability.

Hamster parvovirus (HaPV) was isolated 2 decades ago from hamsters with clinical signs similar to those induced in hamsters experimentally infected with other rodent parvoviruses. Genetically, HaPV is most closely related to mouse parvovirus (MPV), which induces subclinical infection in mice. A novel MPV strain, MPV3, was detected recently in naturally infected mice, and genomic sequence analysis indicates that MPV3 is almost identical to HaPV. The goal of the present studies was to examine the infectivity of HaPV in mice. Neonatal and weanling mice of several mouse strains were inoculated with HaPV. Tissues, excretions, and sera were harvested at 1, 2, 4, and 8 wk after inoculation and evaluated by quantitative PCR and serologic assays specific for HaPV. Quantitative PCR detected viral DNA quantities that greatly exceeded the quantity of virus in inocula in multiple tissues of infected mice. Seroconversion to both nonstructural and structural viral proteins was detected in most immunocompetent mice 2 or more weeks after inoculation with HaPV. In neonatal SCID mice, viral transcripts were detected in lymphoid tissues by RT-PCR and viral DNA was detected in feces by quantitative PCR at 8 wk after inoculation. No clinical signs, gross, or histologic lesions were observed. These findings are similar to those observed in mice infected with MPV. These data support the hypothesis that HaPV and MPV3 are likely variants of the same viral species, for which the mouse is the natural rodent host with rare interspecies transmission to the hamster.

Myoendothelial junctions (MEJs) represent a specialized signaling domain between vascular smooth muscle cells (VSMC) and endothelial cells (EC). The functional consequences of phosphorylation state of the connexins (Cx) at the MEJ have not been explored.

Application of adenosine 3',5'-cyclic monophosphate sodium (pCPT) to mouse cremasteric arterioles reduces the detection of connexin 43 (Cx43) phosphorylated at its carboxyl terminal serine 368 site (S368) at the MEJ in vivo. After single-cell microinjection of a VSMC in mouse cremaster arterioles, only in the presence of pCPT was dye transfer to EC observed. We used a vascular cell co-culture (VCCC) and applied the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (PMA) or fibroblast growth factor-2 (FGF-2) to induce phosphorylation of Cx43 S368. This phosphorylation event was associated with a significant reduction in dye transfer and calcium communication. Using a novel method to monitor increases in intracellular calcium across the in vitro MEJ, we noted that PMA and FGF-2 both inhibited movement of inositol 1,4,5-triphosphate (IP(3)), but to a lesser extent Ca(2+).

These data indicate that site-specific connexin phosphorylation at the MEJ can potentially regulate the movement of solutes between EC and VSMC in the vessel wall.

A strain of the whitefly Bemisia tabaci (Gennadius) possessing unusually high levels of resistance to a wide range of insecticides was discovered in 2004 in the course of routine resistance monitoring in Arizona. The multiply resistant insects, collected from poinsettia (Euphorbia pulcherrima Willd. ex Klotzsch) plants purchased at a retail store in Tucson, were subjected to biotype analysis in three laboratories. Polyacrylamide gel electrophoresis of naphthyl esterases and sequencing of the mitochondrial cytochrome oxidase I gene (780 bp) confirmed the first detection of the Q biotype of B. tabaci in the New World. This U.S. Q biotype strain, referred to as Poinsettia'04, was highly resistant to two selective insect growth regulators, pyriproxyfen and buprofezin, and to mixtures of fenpropathrin and acephate. It was also unusually low in susceptibility to the neonicotinoid insecticides imidacloprid, acetamiprid, and thiamethoxam, relative to B biotype whiteflies. In 100 collections of whiteflies made in Arizona cotton (Gossypium spp.), vegetable, and melon (Cucumis melo L.) fields from 2001 to 2005, no Q biotypes were detected. Regions of the United States that were severely impacted by the introduction of the B biotype of B. tabaci in the 1980s would be well advised to promote measures that limit movement of the Q biotype from controlled environments into field systems and to formulate alternatives for managing this multiply-resistant biotype, in the event that it becomes more widely distributed.

Radiotherapy for head and neck tumors often results in persistent loss of function in salivary glands. Patients suffering from impaired salivary function frequently terminate treatment prematurely because of reduced quality of life caused by malnutrition and other debilitating side-effects. It has been previously shown in mice expressing a constitutively active form of Akt (myr-Akt1), or in mice pretreated with IGF1, apoptosis is suppressed, which correlates with maintained salivary gland function measured by stimulated salivary flow. Induction of cell cycle arrest may be important for this protection by allowing cells time for DNA repair. We have observed increased accumulation of cells in G2/M at acute time-points after irradiation in parotid glands of mice receiving pretreatment with IGF1. As p21, a transcriptional target of the p53 family, is necessary for maintaining G2/M arrest, we analyzed the roles of p53 and p63 in modulating IGF1-stimulated p21 expression. Pretreatment with IGF1 reduces binding of ΔNp63 to the p21 promoter after irradiation, which coincides with increased p53 binding and sustained p21 transcription. Our data indicate a role for ΔNp63 in modulating p53-dependent gene expression and influencing whether a cell death or cell cycle arrest program is initiated.

Radiotherapy for head and neck cancer results in severe and chronic salivary gland dysfunction in most individuals. This results in significant side effects including xerostomia, dysphagia, and malnutrition which are linked to significant reductions in patients' quality of life. Currently there are few xerostomia treatment approaches that provide long-term results without significant side effects. To address this problem we investigated the potential for post-therapeutic IGF-1 to reverse radiation-induced salivary gland dysfunction.

FVB mice were treated with targeted head and neck radiation and significant reductions in salivary function were confirmed 3 days after treatment. On days 4-8 after radiation, one group of mice was injected intravenously with IGF-1 while a second group served as a vehicle control. Stimulated salivary flow rates were evaluated on days 30, 60, and 90 and histological analysis was performed on days 9, 30, 60, and 90.

Irradiated animals receiving vehicle injections have 40-50% reductions in stimulated salivary flow rates throughout the entire time course. Mice receiving injections of IGF-1 have improved stimulated salivary flow rates 30 days after treatment. By days 60-90, IGF-1 injected mice have restored salivary flow rates to unirradiated control mice levels. Parotid tissue sections were stained for amylase as an indicator of functioning acinar cells and significant reductions in total amylase area are detected in irradiated animals compared to unirradiated groups on all days. Post-therapeutic injections of IGF-1 results in increased amylase-positive acinar cell area and improved amylase secretion. Irradiated mice receiving IGF-1 show similar proliferation indices as untreated mice suggesting a return to tissue homeostasis.

Post-therapeutic IGF-1 treatment restores salivary gland function potentially through normalization of cell proliferation and improved expression of amylase. These findings could aid in the rational design of therapy protocols or drugs for the treatment of radiation-induced salivary gland dysfunction in patients who have completed their anti-cancer therapies.

Radiotherapy for head and neck tumors often results in persistent loss of function in salivary glands. Patients suffering from impaired salivary function frequently terminate treatment prematurely because of reduced quality of life caused by malnutrition and other debilitating side-effects. It has been previously shown in mice expressing a constitutively active form of Akt (myr-Akt1), or in mice pretreated with IGF1, apoptosis is suppressed, which correlates with maintained salivary gland function measured by stimulated salivary flow. Induction of cell cycle arrest may be important for this protection by allowing cells time for DNA repair. We have observed increased accumulation of cells in G2/M at acute time-points after irradiation in parotid glands of mice receiving pretreatment with IGF1. As p21, a transcriptional target of the p53 family, is necessary for maintaining G2/M arrest, we analyzed the roles of p53 and p63 in modulating IGF1-stimulated p21 expression. Pretreatment with IGF1 reduces binding of ΔNp63 to the p21 promoter after irradiation, which coincides with increased p53 binding and sustained p21 transcription. Our data indicate a role for ΔNp63 in modulating p53-dependent gene expression and influencing whether a cell death or cell cycle arrest program is initiated.

Quercetin is a unique dietary polyphenol because it can exert biphasic dose-responses on cells depending on its concentration. Cancer preventative effects of quercetin are observed at concentrations of approximately 1-40 microM and are likely mediated by quercetin's antioxidant properties. Pro-oxidant effects are present at cellular concentrations of 40-100 microM. However, at higher concentrations, many novel pathways in addition to ROS contribute to its effects. The potent bioactivity of quercetin has led to vigorous study of this compound and revealed numerous pathways that could interact synergistically to prevent or treat cancer. The effect of intake and concentration on emerging pathways and how they may interact are discussed in this review.

The alkylating agent dacarbazine (DTIC) has been used in the treatment of melanoma for decades, but when used as a monotherapy for cancer only moderate response rates are achieved. Recently, the clinical use of temozolomide (TMZ) has become the more commonly used analog of DTIC-related oral agents because of its greater bioavailability and ability to cross the blood brain barrier. The response rates achieved by TMZ are also unsatisfactory, so there is great interest in identifying compounds that could be used in combination therapy. We have previously demonstrated that the bioflavonoid quercetin (Qct) promoted a p53-mediated response and sensitized melanoma to DTIC. Here we demonstrate that Qct also sensitizes cells to TMZ and propose a mechanism that involves the modulation of a truncated p53 family member, deltaNp73.

DB-1 melanoma (p53 wildtype), and SK Mel 28 (p53 mutant) cell lines were treated with TMZ (400 microM) for 48 hrs followed by Qct (75 microM) for 24 hrs. Cell death was determined by Annexin V-FITC staining and immunocytochemical analysis was carried out to determine protein translocation.

After treatment with TMZ, DB-1 cells demonstrated increased phosphorylation of ataxia telangiectasia mutated (ATM) and p53. However, the cells were resistant to TMZ-induced apoptosis and the resistance was associated with an increase in nuclear localization of deltaNp73. Qct treatment in combination with TMZ abolished drug insensitivity and caused a more than additive induction of apoptosis compared to either treatment alone. Treatment with Qct, caused redistribution of deltaNp73 into the cytoplasm and nucleus, which has been associated with increased p53 transcriptional activity. Knockdown of deltaNp73 restored PARP cleavage in the TMZ treated cells, confirming its anti-apoptotic role. The response to treatment was predominantly p53 mediated as the p53 mutant SK Mel 28 cells showed no significant enhancement of apoptosis.

This study demonstrates that Qct can sensitize cells to TMZ and that the mechanisms of sensitization involve modulation of p53 family members.

Neprilysin (NEP) is a key cell surface peptidase in the maintenance of airway homeostasis and the development of pulmonary disorders. However, little information is available about the effect of particulate matter (PM) on airway NEP. In this controlled human exposure study, changes in induced sputum were measured in 11 subjects at baseline, overshot (OS) mucking, and diesel exhaust (DE) exposure days. Neither OS condition nor DE exposure was found to induce significant changes in total protein, but DE induced significant increases in cell numbers of macrophages and epithelium. Moreover, significant increases in soluble NEP were observed following OS mining dust particulates (0.43 +/- 0.06 nmol/microg protein/min; p = .023) and DE exposure (0.40 +/- 0.03 nmol/microg protein/min; p = .035) when compared with the baseline control (0.30 +/- 0.04 nmol/microg protein/min), with 42% and 31% average net increase, respectively. Pearson's correlation analyses indicated that sputum NEP activity was significantly associated with personal exposure product (elemental carbon concentration [mg/m(3)] x time [min]; C x T). The data suggest that changes in NEP activity may be an early, accurate endpoint for airway epithelial injury and provide a new insight into the mechanism of airway effects following particulate exposure.

The public health workforce is diverse and encompasses a wide range of professions. For tribal communities, the Community Health Representative (CHR) is a public health paraprofessional whose role as a community health educator and health advocate has expanded to become an integral part of the health delivery system of most tribes. CHRs possess a unique set of skills and cultural awareness that make them an essential first responder on tribal land. As a result of their distinctive qualities they have the capability of effectively mobilizing communities during times of crisis and can have a significant impact on the communities' response to a local incident. Although public health emergency preparedness training is a priority of federal, state, local and tribal public health agencies, much of the training currently available is not tailored to meet the unique traits of CHRs. Much of the emergency preparedness training is standardized, such as the Federal Emergency Management Agency (FEMA) Training Programs, and does not take into account the inherent cultural traditions of some of the intended target audience. This paper reports on the use of the Native American Talking Circle format as a culturally appropriate method to teach the Incident Command System (ICS). The results of the evaluation suggest the talking format circle is well received and can significantly improve the understanding of ICS roles. The limitations of the assessment instrument and the cultural adaptations at producing changes in the understanding of ICS history and concepts are discussed. Possible solutions to these limitations are provided.

During embryonic development, cells comprising the outermost layer of the heart or epicardium play a critical role in the formation of the coronary vasculature. Thus, uncovering the molecular mechanisms that govern epicardial cell behavior is imperative to better understand the etiology of cardiovascular diseases. In this study, we investigated the function of hyaluronan (HA), a major component of the extracellular matrix, in the modulation of epicardial signaling. We show that stimulation of epicardial cells with high molecular weight HA (HMW-HA) promotes the association of MEKK1 with the HA receptor CD44 and induces MEKK1 phosphorylation. This leads to the activation of two distinct pathways, one ERK-dependent and another NFkappaB-dependent. Furthermore, HMW-HA stimulates epicardial cells to differentiate and invade, as suggested by increased vimentin expression and enhanced invasion through a collagen matrix. Blockade of CD44, transfection with a kinase-inactive MEKK1 construct or the use of ERK1/2 and NFkappaB inhibitors significantly abrogates the invasive response to HMW-HA. Together, these findings suggest an important role for HA in the regulation of epicardial cell fate via activation of MEKK1 signaling cascades.

The ErbB family of receptor tyrosine kinases (RTKs) is a family of receptors that allow cells to interact with the extracellular environment and transduce signals to the nucleus that promote differentiation, migration and proliferation necessary for proper heart morphogenesis and function. This review focuses on the role of the ErbB family of receptor tyrosine kinases, and their importance in proper heart morphogenesis, as well as their role in maintenance and function of the adult heart. Studies from transgenic mouse models have shown the importance of ErbB receptors in heart development, and provide insight into potential future therapeutic targets to help reduce congenital heart defect (CHD) mortality rates and prevent disease in adults. Cancer therapeutics have also shed light to the ErbB receptors and signaling network, as undesired side effects have demonstrated their importance in adult cardiomyocytes and prevention of cardiomyopathies. This review will discuss ErbB receptor tyrosine kinases (RTK) in heart development and disease including valve formation and partitioning of a four-chambered heart as well as cardiotoxicity when ErbB signaling is attenuated in adults.