Development and initial validation of self-report measures of general health, preoperative anxiety, and postoperative pain in young children using computer-administered animation.

BACKGROUND: For young children, existing measures of children's health-related quality of life must be parent-reported or interviewer-administered for those who cannot read or complete measures independently. Parents' and childrens' reports about the child's health have been shown to disagree. AIMS: (a) To test the reliability and validity of an animated, computer-administered Child Health Rating Inventories (CHRIS2.0) among children aged 4-12 undergoing surgery; and (b) to develop and test two CHRIS measures of preoperative anxiety and postoperative pain management. METHODS: We conducted a longitudinal cohort study of a diverse group of 542 children aged 4-12 undergoing surgery. We compared the CHRIS measures to Pediatric Quality of Life Inventory (PedsQL), the Functional Disabilities Inventory (FDI), State-Trait Anxiety Inventory for children (STAI-CH), and the Parent Postoperative Pain Measure (PPPM). RESULTS: Factor analyses supported the construct validity of the 12-item general physical health and the 8-item mental health CHRIS scales, as well as a composite 20-item scale, and the CHRIS preoperative anxiety and postoperative pain scales. Internal consistency reliability for all CHRIS scales exceeded the standard for group comparisons (Cronbach's α ≥0.70). The CHRIS general health composite was significantly correlated with composite PedsQL and FDI (r = 0.28, P < .001 and r = 0.43, P < .001, respectively). The CHRIS peri-operative anxiety measure was significantly correlated with the STAI-CH (r = 0.44, P < .001), as was the CHRIS postoperative pain scale with the PPPM (r = 0.52, P < .001). CONCLUSIONS: The CHRIS measures were reliable and valid in this diverse sample of young children (4-12). Because CHRIS measures are self-administered, scored in real time, and run on multiple different platforms, this approach provides a feasible method for the collection of health-related quality of life in young children and those with limited literacy. Our data indicate that this approach is psychometrically sound and has the potential for adding the child's voice to pediatric outcomes.

En Route to New Therapeutic Options for Iron Overload Diseases: Matriptase-2 as a Target for Kunitz-Type Inhibitors.

The cell-surface serine protease matriptase-2 is a critical stimulator of iron absorption by negatively regulating hepcidin, the key hormone of iron homeostasis. Thus, it has attracted much attention as a target in primary and secondary iron overload diseases. Here, we have characterised Kunitz-type inhibitors hepatocyte growth factor activator inhibitor 1 (HAI-1) and HAI-2 as powerful, slow-binding matriptase-2 inhibitors. The binding modes of the matriptase-2-HAI complexes were suggested by molecular modelling. Different assays, including cell-free and cell-based measurements of matriptase-2 activity, determination of inhibition constants and evaluation of matriptase-2 inhibition by analysis of downstream effects in human liver cells, demonstrated that matriptase-2 is an excellent target for Kunitz inhibitors. In particular, HAI-2 is considered a promising scaffold for the design of potent and selective matriptase-2 inhibitors.

Cell surface serine protease matriptase-2 suppresses fetuin-A/AHSG-mediated induction of hepcidin.

Matriptase-2 is a type II transmembrane serine protease controlling the expression of hepcidin, the key regulator of iron homeostasis. By cleaving hemojuvelin, matriptase-2 suppresses bone morphogenetic protein/sons of mothers against decapentaplegic signaling. So far, the only known putative substrates of matriptase-2 are hemojuvelin and matriptase-2 itself. In this study, fetuin-A (α2-Heremans-Schmid glycoprotein) was identified in vitro as a substrate of matriptase-2. The protease-substrate interaction was validated by isolating matriptase-2 via the affinity to fetuin-A. Fetuin-A is a liver-derived plasma protein with multiple functions, which is proteolytically processed to yield a disulfide-linked two-chain form. In co-transfected cells, a matriptase-2-dependent conversion of unprocessed fetuin-A into a two-chain form was detected. Conversely, downregulation of endogenously expressed matriptase-2 stabilized fetuin-A. Arg and Lys residues located within the 40 residue spanning connecting peptide of fetuin-A were identified as cleavage sites for matriptase-2. Analysis of hepcidin expression revealed an inductive effect of fetuin-A, which was abolished by matriptase-2. Fetuin-A deficiency in mice resulted in decreased hepcidin mRNA levels. These findings implicate a role of fetuin-A in iron homeostasis and provide new insights into the mechanism of how matriptase-2 might modulate hepcidin expression.

Pain management at home in children with cancer: a daily diary study.

BACKGROUND: With the transition of care of cancer patients from the hospital to the home setting, parents are largely responsible for children's pain management. Children's cancer pain is undermanaged, yet, there is little empirical data on the occurrence and management of cancer pain in the home setting. The purpose of the present study, therefore, was to employ a daily diary protocol to examine barriers to pain management of children's cancer pain by parents at home. PROCEDURE: Parent-child dyads were recruited from the Cancer Institute at a major children's hospital in Southern California. A total of 45 patient/parent pairs completed baseline data on demographic and personality characteristics, children's quality of life, and parental beliefs regarding analgesic use for children and then completed daily diaries of pain and analgesic administration for 14 consecutive days. RESULTS: Most children were reported to experience chronic pain while undergoing treatment for cancer, yet overall analgesic administration at home was low. Parents who reported misconceptions regarding analgesic use for children were less likely to administer pain medication to children. Children who were less shy, more social, or had lower quality of life were more likely to receive analgesics. CONCLUSIONS: A significant proportion of children receiving outpatient treatment for cancer were rated as experiencing chronic pain and pain was not optimally managed in the home setting. Further understanding and addressing barriers to children's cancer pain management in the home setting will aid in alleviating unnecessary pain in this vulnerable patient population.

Hepatocyte growth factor activator inhibitor type 2 (HAI-2) modulates hepcidin expression by inhibiting the cell surface protease matriptase-2.

Matriptase-2, a recently identified cell surface protease, is the key enzyme of iron homoeostasis modulating the expression of the liver peptide hormone hepcidin. HAI (hepatocyte growth factor activator inhibitor) types 1 and 2 (HAI-1 and HAI-2 respectively) have been shown to inhibit the close homologue, i.e. matriptase. By co-expressing matriptase-2 and the inhibitor HAI-2 we have identified HAI-2 displaying high inhibitory potential against matriptase-2 at the cell surface as well as in conditioned medium. Accordingly, complex formation between matriptase-2 and HAI-2 was demonstrated by isolation of the complex via immobilizing either HAI-2 or matriptase-2 from lysates and conditioned medium of co-expressing cells. Furthermore, HAI-2 indirectly influences the expression of the hepcidin-encoding gene HAMP. The inhibitor abrogates the matriptase-2-mediated suppression of HAMP expression, presumably by inhibiting the supposed potential of matriptase-2 to cleave membrane-bound HJV (haemojuvelin). Taken together, the results of the present study have characterized HAI-2 as an inhibitor of matriptase-2 that modulates the synthesis of hepcidin and provides new insights into the regulatory mechanism of iron homoeostasis, with clinical importance for a treatment of iron overload diseases.

Matriptase-2 (TMPRSS6) is directly up-regulated by hypoxia inducible factor-1: identification of a hypoxia-responsive element in the TMPRSS6 promoter region.

The type II transmembrane serine protease matriptase-2 (TMPRSS6) down-regulates the expression of hepcidin, the main regulator of systemic iron homeostasis, and increases in this way iron plasma levels. Matriptase-2 is up-regulated under hypoxic conditions, providing a new link between hypoxia signaling and iron homeostasis. In this study, we have characterized the TMPRSS6 promoter region and identified a functional hypoxia-responsive element (HRE). Mutations of the hypoxia inducible factor (HIF)-binding site located within the HRE abrogate HIF-1α-dependent induction of TMPRSS6 expression. The action of HIF-1α on TMPRSS6 promoter activity reveals a new regulative element for the suppression of hepcidin synthesis.

Active site mapping of trypsin, thrombin and matriptase-2 by sulfamoyl benzamidines.

The benzamidine moiety, a well-known arginine mimetic, has been introduced in a variety of ligands, including peptidomimetic inhibitors of trypsin-like serine proteases. According to their primary substrate specificity, the benzamidine residue interacts with the negatively charged aspartate at the bottom of the S1 pocket of such enzymes. Six series of benzamidine derivatives (1-73) were synthesized and evaluated as inhibitors of two prototype serine proteases, that is, bovine trypsin and human thrombin. As a further target, human matriptase-2, a recently discovered type II transmembrane serine protease, was investigated. Matriptase-2 represents an important regulatory protease in iron homeostasis by down-regulation of the hepcidin expression. Compounds 1-73 were designed to contain a fixed sulfamoyl benzamidine moiety as arginine mimetic and a linker-connected additional substructure, such as a tert-butyl ester, carboxylate or second benzamidine functionality. A systematic mapping approach was performed with these inhibitors to scan the active site of the three target proteases. In particular, bisbenzamidines, able to interact with both the S1 and S3/S4 binding sites, showed notable affinity. In branched bisbenzamidines 66-73 containing a third hydrophobic residue, opposite effects of the stereochemistry on trypsin and thrombin inhibition were observed.

Attitudes regarding analgesic use and pain expression in parents of children with cancer.

BACKGROUND: Children with cancer often experience significant levels of pain and their pain is generally undermanaged. Management of care to patients with cancer has shifted from the hospital to the home, and as such parents are charged with managing children's pain. However, parents may have misconceptions of analgesic use, which can lead to undertreatment of pain in children. The purpose of this study is to examine attitudes toward pain medication and perceptions of pain expression among parents of children undergoing cancer treatment. PROCEDURE: Parents of children who were undergoing cancer treatment at a hospital were recruited to take part in a survey study. A total of 187 parents completed a survey examining their attitudes toward medication and perceptions of pain expression in children. RESULTS: Many parents reported concerns regarding analgesic use to treat their children's pain and misconceptions about how children can express pain. Regression analyses noted that parental perceptions of pain expression were related to children's experience of chronic or recurring pain and the 2 dimensions of child temperament: emotionality and sociability. CONCLUSIONS: Many parents of children with cancer have misconceptions regarding issues of pain management; these misconceptions can potentially lead to undertreatment of pain in children. These misconceptions are associated with aspects of children's temperament.

Hydrotrope-induced inversion of salt effects on the cloud point of an extended surfactant.

We report on the effects of electrolytes spanning a range of anions (NaOc, NaSCN, NaNO(3), NaBr, NaCl, NaBu, NaOAc, Na(2)SO(4), Na(2)HPO(4), and Na(2)CO(3)) and cations (LiCl, NaCl, KCl, CsCl, and choline chloride) on the aqueous solubility of an extended surfactant. The surfactant is anionic with a long hydrophobic tail as well as a significant fraction of propylene oxide groups and ethylene oxide groups (C(12-14)-PO(16)-EO(2)-SO(4)Na, X-AES). In the absence of electrolytes, X-AES exhibits a cloud-point temperature that decreases with increasing surfactant concentration. After the addition of salts to the surfactant solutions, various shifts in the solubility curves are observed. These shifts follow precisely the same Hofmeister series that is found for salting-in and salting-out effects in protein solutions. In the presence of different concentrations of sodium xylene sulfonate (SXS), the solubility of the surfactant increases. In this context, SXS can be considered to be a salting-in salt. However, when the electrolytes are added to an aqueous solution of X-AES and SXS the Hofmeister series reverses for divalent anions such as Na(2)SO(4), Na(2)HPO(4), and Na(2)CO(3). Studies on the phase behavior and micelle structures using polarization microscopy, freeze-etch TEM, and NMR measurements indicate a dramatic change in the coexisting phases on the addition of SXS.

Proteolytic processing of the serine protease matriptase-2: identification of the cleavage sites required for its autocatalytic release from the cell surface.

Matriptase-2 is a member of the TTSPs (type II transmembrane serine proteases), an emerging class of cell surface proteases involved in tissue homoeostasis and several human disorders. Matriptase-2 exhibits a domain organization similar to other TTSPs, with a cytoplasmic N-terminus, a transmembrane domain and an extracellular C-terminus containing the non-catalytic stem region and the protease domain. To gain further insight into the biochemical functions of matriptase-2, we characterized the subcellular localization of the monomeric and multimeric form and identified cell surface shedding as a defining point in its proteolytic processing. Using HEK (human embryonic kidney)-293 cells, stably transfected with cDNA encoding human matriptase-2, we demonstrate a cell membrane localization for the inactive single-chain zymogen. Membrane-associated matriptase-2 is highly N-glycosylated and occurs in monomeric, as well as multimeric, forms covalently linked by disulfide bonds. Furthermore, matriptase-2 undergoes shedding into the conditioned medium as an activated two-chain form containing the catalytic domain, which is cleaved at the canonical activation motif, but is linked to a released portion of the stem region via a conserved disulfide bond. Cleavage sites were identified by MS, sequencing and mutational analysis. Interestingly, cell surface shedding and activation of a matriptase-2 variant bearing a mutation at the active-site serine residue is dependent on the catalytic activity of co-expressed or co-incubated wild-type matriptase-2, indicating a transactivation and trans-shedding mechanism.

Sleep, rhythms and women's mood. Part I. Menstrual cycle, pregnancy and postpartum.

This review summarizes studies of sleep and other biological rhythms during the menstrual cycle, pregnancy and the postpartum period, focusing, where feasible, on studies in women who met DSM-IV (Diagnostic and Statistical Manual for Mental Disorders, 4th edition) criteria for a depressive disorder compared with healthy controls. The aim was to review supporting evidence for the hypothesis that disruption of the normal temporal relationship between sleep and other biological rhythms such as melatonin, core body temperature, cortisol, thyroid stimulating hormone (TSH) or prolactin occurring during times of reproductive hormonal change precipitates depressive disorders in predisposed women. Treatment strategies, designed to correct these altered phase (timing) or amplitude abnormalities, thereby improve mood. Although there may be some common features to premenstrual, pregnancy and postpartum depressive disorders (e.g. elevated prolactin levels), a specific profile of sleep and biological rhythms distinguishes healthy from depressed women during each reproductive epoch. Further work is needed to characterize more fully the particular abnormalities associated with each reproductive state to identify common versus distinctive features for each diagnostic group. This information could serve as the basis for developing more targeted treatment strategies.

Sleep, rhythms and women's mood. Part II. Menopause.

This review summarizes studies of sleep and other biological rhythms in menopausal women with major depression compared with healthy control subjects. Where feasible, we focused on studies in women who met DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) criteria for a major depressive episode (MDE) compared with matched normal control subjects and the Staging System for Reproductive Aging in Women (STRAW) criteria. The aim was to review supporting evidence for the hypothesis that a disruption of the normal temporal relationship between sleep and other biological rhythms, such as melatonin, cortisol, thyroid stimulating hormone (TSH) or prolactin, occur during the menopausal transition. As a result, depressive disorders occur in predisposed women. Treatment strategies, designed to correct these altered phase (timing) or amplitude abnormalities, thereby improve mood. Although there may be some common features to menopausal depression compared with other depressive disorders related to the reproductive cycle (e.g. premenstrual dysphoric disorder or postpartum major depression), such as increased morning melatonin secretion, a specific profile of sleep and biological rhythms may distinguish healthy from depressed women during menopause. Further work is needed to characterize more fully the particular abnormalities associated with well-defined menopausal depression in order to develop treatment strategies targeted more specifically to pathogenesis.

Light treatment of mood disorders.

In 1981, seven patients with nonseasonal depression were treated with bright white light in 1982, bright artificial light was used to treat a manic-depressive patient with a seasonal mood cycle. In the last 20 years, a plethora of studies have further defined the depressive populations, who are responsive to light treatment; the optimal timing, intensity, spectral frequency, and duration of treatment; its comparison with other pharmacological interventions; predictors of response; side-effect profiles; viable placebo-control conditions; alternative devices and forms of administration; potential mechanisms and anatomical pathways mediating light's physiological effects; and its application to other disorders and subsyndromaI states. These studies have been conducted across multiple countries with surprisingly consistent results. Further work is needed, as highlighted in this review, to clarify the specific mechanism of action in subtypes of depressive disorders and differential age and gender effects. Although the majority of work in this area is relatively new, it behooves the reader to remember that Solomon, almost 3000 years ago, wrote in Ecclesiastes: "Truly the light is sweet and a pleasant thing it is for the eyes to behold the sun" (11:7).

Oligoether carboxylates: task-specific room-temperature ionic liquids.

Recently, a new family of ionic liquids based on oligoether carboxylates was introduced. 2,5,8,11-Tetraoxatridecan-13-oate (TOTO) was shown to form room-temperature ionic liquids (RTILs) even with small alkali ions such as lithium and sodium. However, the alkali TOTO salts suffer from their extremely high viscosities and relatively low conductivities. Therefore, we replaced the alkali cations by tetraalkylammonium (TAA) ions and studied the TOTO salts of tetraethyl- (TEA), tetrapropyl- (TPA), and tetrabutylammonium (TBA). In addition, the environmentally benign quaternary ammonium ion choline (Ch) was included in the series. All salts were found to be ionic liquids at ambient temperatures with a glass transition typically at around -60 °C. Viscosities, conductivities, solvent polarities, and Kamlet-Taft parameters were determined as a function of temperature. When using quaternary ammonium ions, the viscosities of the resulting TOTO ionic liquids are >600 times lower, whereas conductivities increase by a factor of up to 1000 compared with their alkali counterparts. Solvent polarities further reveal that choline and TAA cations yield TOTO ionic liquids that are more polar than those obtained with the, per se, highly polar sodium ion. Results are discussed in terms of ion-pairing and structure-breaking concepts with regard to a possible complexation ability of the TOTO anion.

Acute to chronic postoperative pain in children: preliminary findings.

BACKGROUND/PURPOSE: Chronic postoperative pain is a well-established clinical phenomenon that is associated with adverse outcomes. The incidence of this clinical phenomenon in children, however, is not well established. The purpose of this study was to identify the incidence of chronic pain in children after surgery. METHODS: Following a screening process, a total of 113 children and their parents were enrolled in this cross-sectional study. Data regarding persistence and characteristics of pain after surgery were obtained. RESULTS: Approximately 13% of the children, most of whom underwent orthopedic procedures, reported the existence of symptoms of chronic postoperative pain. Most of the children indicated that the pain started immediately after surgery, was localized to the surgery site, and was intermittent. Children reported a median duration of pain of 4.1 months, and approximately half of the children experienced pain most days of the week. Up to 30% of the children reported interference of pain in functioning in areas such as extracurricular activities and sleep. DISCUSSION: Given the large number of children at risk for experiencing chronic postoperative pain, preventative efforts are necessary. Large-scale cohort prospective studies are needed to confirm the results of this cross-sectional study.

Identification of the first low-molecular-weight inhibitors of matriptase-2.

As recently discovered, matriptase-2, a type II transmembrane serine protease, plays a crucial role in body iron homeostasis by down-regulating hepcidin expression, which results in increased iron levels. Thus, matriptase-2 represents a novel target for the development of enzyme inhibitors potentially useful for the treatment of systemic iron overload (hemochromatosis). A comparative three-dimensional model of the catalytic domain of matriptase-2 was generated and utilized for structure-based virtual screening in combination with similarity searching and knowledge-based compound design. Two N-protected dipeptide amides containing a 4-amidinobenzylamide as P1 residue (compounds 1 and 3) were identified as the first small molecule inhibitors of matriptase-2 with K(i) values of 170 and 460 nM, respectively. An inhibitor of the closely related protease matriptase (compound 2, K(i) = 220 nM), with more than 50-fold selectivity over matriptase-2, was also identified.

Kids, adolescents, and young adult cancer study-a methodologic approach in cancer epidemiology research.

Advances have been made in treatment and outcomes for pediatric cancer. However adolescents and young adults (AYAs) with cancer have not experienced similar relative improvements. We undertook a study to develop the methodology necessary for epidemiologic cancer research in these age groups. Our goal was to create the Kids, Adolescents, and Young Adults Cancer (KAYAC) project to create a resource to address research questions relevant to this population. We used a combination of clinic and population-based ascertainment to enroll 111 cases aged 0-39 for this methodology development study. The largest groups of cancer types enrolled include: breast cancer, leukemia, lymphoma, and melanoma. The overall participation rate is 69.8% and varies by age and tumor type. The study included patients, mothers, and fathers. The methods used to establish this resource are described, and the values of the resource in studies of childhood and young adult cancer are outlined.

Ion exchange in catanionic mixtures: from ion pair amphiphiles to surfactant mixtures.

We have studied concentrated equimolar mixtures of tetradecanoic acid (myristic acid, C13COOH) and hexadecyltrimethylammonium hydroxide (CTAOH) in which the OH- counterions are gradually exchanged by other anions (Cl-, Br-, CH3COO-, CH3-(C6H4)-SO3-). We demonstrate that the stability of a Lbeta phase can be achieved at equimolarity between both surfactants, provided that the phase contains also a sufficient number of anions exchanged with OH-. In the absence of exchange (equimolar mixture of C13COOH and CTAOH), a three-dimensional crystalline Lc phase is produced. As the OH- ions are replaced by other ions, a swollen Lbeta lamellar phase appears, first in coexistence with the Lc (D* = 400 A) and then in coexistence with a dilute phase only (D* = 215 A). In the latter regime, the repeating distance depends very little on the exchange ratio, but rather on the nature of the counterion. If too many OH- ions are exchanged, the Lbeta phase becomes unstable again. A Poisson-Boltzmann model with charge regulation computed for a closed system predicts qualitatively the existence of this narrow domain of stability for the Lbeta phase.