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This study used the broaden-and-build theory of positive emotions to examine the relationship between coping strategies and psychological well-being in military spouses. The goal was to det...

The purpose of this study was to identify the protective roles of religious faith and family support in buffering against suicidal behavior in a sample of substance abuse outpatients seeking treatment. Data were collected from 112 clinical outpatients seeking treatment for substance abuse. We hypothesized that religious faith would be related to lower levels of suicidal behavior through a negative association with depressive symptoms. We expected this mediation effect would differ across varying levels of family support, providing support for a moderated mediation effect. The results indicate that religious faith exerts stronger direct and indirect effects on suicidal behavior at low levels of family support. Religious faith was significantly and negatively related to suicidal behavior only at low levels of family support. The findings suggest that in the absence of family support, religious faith may play a compensatory role in protecting against suicidal behavior.

The goal of this study was to identify positive factors that increase the psychological well-being of military spouses in the areas of environmental mastery. We proposed that positive affect and social support from family and friends would have indirect effects on psychological well-being through their association with a greater sense of community with the military culture. Participants were 207 female spouses of active-duty service members. Data were analyzed using MEDIATE to test the mediational effect. Results indicated that social support from friends and positive affect did predict a sense of community, which in turn was associated with increased feelings of psychological well-being. The findings suggest that a perceived sense of military community helps military spouses gain a sense of mastery and control in a constantly changing environment.

This study addresses the paucity of knowledge on protective factors associated with Asian American college students' suicidal behavior. Participants were 58 Asian American college students who seriously considered suicide within the past 12 months and responded to open-ended online survey questions about what was helpful during their suicide crisis. A phenomenological analysis of participants' narratives revealed the following protective factors: (a) a desire not to hurt or burden others, (b) social support, (c) fear, (d) self-reliance, and (e) insight. These findings can guide culturally informed clinical interventions by mental health professionals.

This chapter describes inclusive, culturally competent practices for psychological providers and religious leaders providing support for survivors with disabilities of Christian faith backgrounds. There is little empirical data on pastoral response to intimate partner violence in women with disabilities (WWDs). Literature on pastoral response to women experiencing IPV is reviewed as well as models of disability and implicit biases against those with disabilities that faith leaders may unconsciously ascribe to and display in their interactions with those with disabilities. Next, the authors describe their qualitative study of responses (n = 19) to WWD experiencing IPV from a select sample of pastors noted for being welcoming of persons with disabilities. Finally, practical suggestions for providing support to WWD experiencing IPV are shared such as empowering the survivor as opposed to directing the survivor, especially being wary of ableism, pity, protectionism, and inaccurate stereotypes of WWDs.

This mixed-methods study was designed to demonstrate how an increase in generous actions influences an individual’s self-reported long-term happiness. Participants were 74 college students randomly assigned to 1 of 2 experimental conditions—the generosity intervention group and the control group. Data collected on psychological well-being and life satisfaction were analyzed using multivariate analyses of covariance. The quantitative results indicated that even though all participants showed increased levels of satisfaction with life and overall positive psychological well-being after 5 weeks of a writing intervention, there were no differences between the generosity group and the writing group. Additional results from a qualitative analysis further revealed that generosity themes toward oneself centered on (a) material acquisition, (b) luxury, and (c) self-care. The findings support the positive effect of a multilevel, intentional focus on generous activities among young adults.

The purpose of this study was to contribute to the nascent literature on resilience and suicidality among Black Americans by examining factors that may predict less suicidal behavior among this population. The authors hypothesized that reasons for living, life satisfaction, and religious awareness would account for unique variance in suicidal thoughts and behavior among Black Americans, above the variance accounted for by depressive symptoms. They also hypothesized that reasons for living and religious awareness would be stronger inverse predictors among Black women than Black men. Results indicated that both depression and life satisfaction were stronger predictors of suicidal behavior among Black men. Among women, only reasons for living was a significant inverse predictor of suicidal thoughts and behavior. More frequent reasons for living moderated the relationship between depression and suicidal thoughts and behavior among Black women.

More than 33,000 people commit suicide and approximately 756,000 people attempt suicide in the United States each year (Arias, Anderson, Kung, Murphy, & Kochanek, 2003). In 2007, suicide was the third leading cause of death among 15-to 24-year-old Black Americans (Xu, Kochanek, Murphy, & Tejada-Vera, 2010). In addition, Black college students have been shown to attempt suicide more often than their White counterparts (Kann et al., 1998). Although there is ample research on suicidality among North Americans, most of this research has been conducted with White individuals, and investigations of suicide among Black persons are lacking. To promote Black individuals' well-being and eliminate suicide incidents, counselors need to examine the reasons underlying this increase in suicidality, as well as possible ways to prevent or reduce the number of individuals from taking their own lives. Therefore, the purpose of this study was to research positive factors that reduce the likelihood for individuals to engage in suicide behavior. More specifically, the study was designed to examine the roles of coping and reasons for living in protecting against suicide in a sample of Black college students. * Coping Stress is an inevitable aspect of daily life; however, the way an individual responds to the negative or stressful events can vary. Lazarus and Folkman (1984) theorized coping as the cognitive and behavioral efforts of an individual utilized to manage external or internal demands rising from stressful life events. Coping has been shown to play a mediator role between antecedent stressful event and psychological distress such as anxiety, depression, and suicide (Dixon, Heppner, & Anderson, 1991; Elliott, Sherwin, Harkins, & Marmarosh, 1995). How an individual appraises the situation and his or her ability to manage the situation seem to be related to the level of psychological distress the individual may experience under the circumstance. Fewer coping skills may be associated with higher levels of psychological distress under stressful events. For people who attempt suicide or who have suicidal ideation, studies have found that these individuals seem to have less developed coping strategies or use these coping skills less frequently (Botsis, Soldators, Liossi, Kokkevi, & Stefanis, 1994; Kaslow et al., 2002; Kralik & Danforth, 1992). Although adaptive coping may facilitate finding solutions in resolving challenges, maladaptive coping may worsen the situation. Because of a lack of more adaptive coping skills, some individuals who attempt suicide may use suicide as a means of coping with highly stressful situations. Lazarus and Folkman (1984) conceptualized coping into two categories: emotion-focused coping, which focuses on releasing and reducing the emotional distress coming from the stressor, and problem-focused coping, which directs attention to ways of resolving the situation. In addition to these two types of coping, Endler and Parker (1994) added avoidance-oriented coping, in which an individual uses strategies that temporarily distract him or her from the stressful situation. An early meta-analysis study (Suls & Fletcher, 1985) indicated that emotion-focused coping is associated with more negative psychological outcomes than are problem-focused coping and avoidance-oriented coping. The literature on suicide seems to agree with this finding in that emotion-oriented coping may be associated with a higher level of suicidal behavior (Edwards & Holden, 2001; Puskar, Hoover, & Miewald, 1992). A recent path study (Wang, Lightsey, Pietruszka, Uruk, & Wells, 2007) found that the more stressful events occur in life, the more likely individuals are to use emotion-focused coping. Emotion-oriented coping seemed to increase suicidal behavior by increasing levels of depression and reducing an individual's reasons for living. Wang et al. (2007) also reported that avoidance-oriented coping reduced suicidal risk by increasing reasons for living. …

Chaotic motion is an undesirable phenomenon in many engineering applications since it leads to a significant degradation of the system performance and restricts the feasible operational range. Therefore, the problem of controlling or suppressing chaos has attracted considerable attention in the literature. However, most chaos control schemes utilize a state feedback signal, and are therefore sensitive to measurement noise. Therefore, a requirement exists for filtering systems capable of separating the measurement noise from the chaotic signal in order to improve the performance of the controlled system. However, the chaotic signal and the measurement noise are both broadband signals, and thus the measurement noise can not be filtered using a low-pass filter since this causes a distortion of the chaotic signal. Accordingly, this paper presents a control scheme for chaotic dynamic systems with significant measurement noise featuring an input-state linearization scheme and a filter based upon an independent component analysis algorithm. The feasibility and effectiveness of the proposed approach are demonstrated by way of numerical simulations using a general Lorenz system for illustration purposes.

This article presents a grounded theory analysis of the experience of sustaining an abiding curiosity. Results emphasize how curiosity became inherently motivating and pleasurable, and led to deeper understandings of interpersonal differences and an enriched sense of identity. Despite the experience of curiosity strengthening, waning, and shifting across time, it was experienced as a longstanding driving force. At the same time, if consuming, curiosity holds risks for participants and could lead to alienation from others and despair. The discussion puts forward a more integrated understanding of a somewhat fragmented literature and highlights the complexities that depth curiosity entails.

The aim of this study was to determine the role of family of origin violence in predicting intimate partner violence (IPV). Male participants were divided into generally offending and family-only groups according to whether their violence occurred exclusively within intimate partner and family contexts or toward others outside the family as well. Results showed that exposure to family of origin violence affected IPV differently between the two groups of offenders. For generally offending offenders, exposure to family of origin violence significantly predicted IPV above and beyond demographic factors, alcohol and drug use, and bidirectional aggression. For family-only offenders, witnessing father-initiated violence toward the mother had a significant influence on their violent behavior toward their intimate partners. Clinical implications of these findings are addressed.

The authors tested whether coping styles and fear of pain mediate the relationship between positive affect and negative affect on one hand and pain-related distress (PD) on the other. Among African American and Caucasian female college students, negative affect, fear of pan, and emotion-oriented coping together accounted for 34% of the variance in PD among African American woman and 40% of the variance in PD among Caucasion women. Emotion-oriented coping and fear of pain fully mediated the relationship between negative affect and PD among Caucasian women and partly mediated the relationship between negative affect and PD among African American women. Results suggest that reducing college women's reliance on emotion-oriented coping and their fears of pain may help reduce PD.

Positive psychological factors that help protect vulnerable persons from suicidal behavior are vital in understanding resiliency and suicide prevention. The purpose of the current study was to examine whether positive factors (including purpose in life, reasons for living, and coping styles) mediate the relationship between stressful life events and suicidal behaviors among 416 college student volunteers. Reasons for living inversely predicted suicidal behavior and thoughts directly as well as indirectly via an inverse relationship with depression. Purpose in life indirectly predicted suicidal behavior and thoughts via an inverse effect on depression, whereas emotion-focused coping indirectly predicted suicidal behavior and thoughts both through an effect on depression and an inverse effect on reasons for living. In addition, avoidant coping indirectly predicted suicidal behavior via a direct, positive effect on reasons for living. Reasons for living and emotion-oriented coping had the largest effects in ...

Although close associations between tinnitus and posttraumatic stress disorder (PTSD) among war veterans has been documented, there is limited research that explores evidence-based, efficacious interventions to treat the condition in this particular population. This article presents a case of three war veterans with PTSD symptoms who received a series of acupuncture treatments for tinnitus with positive outcomes. Even though the article presents cases of only three veterans and was based on self-reports, there were very clear trends on how veterans with tinnitus symptoms responded to acupuncture treatments. Information generated from this case presentation is a good starting place in exploring evidence-based approaches in treating tinnitus symptoms in war veterans with PTSD.

The goal of this work was to characterize the roles of mu-calpain in skeletal muscle protein degradation. Three approaches were developed to alter mu-calpain activity in rat myotubes. These included over-expression of antisense mu-calpain (mu-AS), dominant negative mu-calpain (mu-DN) and the antisense 30-kDa calpain subunit (30-AS). Constructs were expressed in rat L8 myotubes, and their effects on protein degradation and on concentrations of intact and/or degraded fodrin, desmin and tropomyosin were examined. An ecdysone-inducible expression system, in which we replaced a constitutively active CMV promoter with a skeletal muscle-specific alpha-actin promoter, was used to drive expression. Cell lines were evaluated by expression of the gene-of-interest following addition of ponasterone A (PA; ecdysone analog) to culture medium. Changes in calpain activity were assessed by evaluating fodrin degradation. 30-AS, which should alter both mu- and m-calpain activities, increased intact fodrin concentration. mu-DN and mu-AS reduced fodrin degradation products. mu-DN reduced total protein degradation by 7.9% (P0.01) at 24 h and by 10.6% (P0.01) at 48 h. mu-AS reduced total protein degradation by 6.4% at 24 h (P0.05). 30-AS reduced total protein degradation by 13.4% (P0.05) and 7.3% (P0.05) following 24 and 48 h of PA administration, respectively. We assessed effects of mu-DN, mu-AS and 30-AS on concentrations of desmin and tropomyosin. Inhibition of calpains stabilized desmin, but had no effect on tropomyosin. These data indicate that fodrin and desmin are mu-calpain substrates and that mu-calpain accounts for a small proportion of total protein degradation in muscle cells. Tropomyosin is not degraded by calpain in muscle cells.

The goal of this study was to identify calpain substrates in muscle cells. Our hypothesis was that the yeast two-hybrid method could be used to identify novel calpain substrates. To accomplish this, native mu- and m-calpains, as well as a variety of calpain DNA fragments, were expressed in yeast cells and used to screen for binding proteins in a human skeletal muscle cDNA library. Calpain constructs that were used in the screening process included native mu- and m-calpains, a dominant negative (DN) m-calpain (i.e. active site modified), N-terminal truncated DN m-calpain (i.e. autolyzed DN-m-calpain) and, finally, an N- and C-terminal truncated m-calpain (i.e. autolyzed DN-m-calpain lacking a calcium-binding domain). Yeast cells were transformed using yeast two-hybrid expression vectors containing the different calpain constructs as "baits". Beta-galactosidase activity was assayed as an index of interaction between calpain and its potential target proteins. From this analysis, four clones (Ca2+-ATPase, novel nebulin-related protein (N-RAP), creatine kinase and glycogen phosphorylase) were recovered. Two of these, creatine kinase and glycogen phosphorylase, were selected for further study. In in-vitro assays, calpain was able to partially digest both proteins, suggesting that both creatine kinase and glycogen phosphorylase are natural calpain substrates.

The goal of the study was to evaluate the mechanism by which ciliary neurotrophic factor (CNTF) regulated protein metabolism in skeletal muscle. L8 myotubes were cultured and effects of various times and doses of CNTF on protein synthesis and degradation were evaluated. Effects of CNTF on turnover of specific pools of proteins (myofibrillar and non-myofibrillar) were also evaluated. Protein synthesis was assayed by incorporation of radioactive tyrosine into muscle proteins. Degradation was assessed by release of labelled tyrosine from pre-labelled myotubes. Effects of CNTF on protein turnover were found to be time- and dose-dependent. CNTF (1 and 10 ng/ml) increased myofibrillar protein synthesis after 12 h of exposure but had no effect on non-myofibrillar protein synthesis. Longer exposures of CNTF (24 h) reduced non-myofibrillar protein synthesis and had no effect on myofibrillar protein synthesis. High concentrations of CNTF (10 and 20 ng/ml) reduced myofibrillar protein degradation but had no effect on degradation of non-myofibrillar proteins. To evaluate the mechanism by which CNTF exerts control of protein turnover, we completed a Northern blot for CNTF receptor alpha-subunit (CNTFRalpha). This was non-detectable via conventional northern analysis. Use of RT-PCR, however, confirmed expression of CNTFRalpha, albeit at a low level compared to rat skeletal muscle. This low expression of the receptor in L8 myotubes may explain the limited effect of CNTF in vitro compared to the larger effects typically detected in vivo. CNTF regulated protein turnover through control of protein synthesis and degradation. Effects were dose and timedependent. These observations may explain ability of CNTF to exert both anabolic and catabolic actions in vivo.

This study utilized an ecological framework to explore the role of 4 culturally relevant protective factors-reasons for living, Afrocentric worldview, family support, and friend support-in protecting Black American college students from suicidal behavior. Participants were 289 Black American college students. We hypothesized that these 4 culturally relevant factors would exert indirect protective effects on suicidal behavior through their association with reduced depressive symptoms. Results indicated that reasons for living, perceived supportive behaviors from family, and Afrocentric worldview exerted indirect protective effects on suicidal behaviors through their negative associations with depressive symptoms. The mediation effect from friend support to depression and suicidal behavior was not significant.

Background The invasion-metastasis cascade of cancer involves a process of parallel progression. A biological interface (module) in which cells is linked with ECM (extracellular matrix) by CAMs (cell adhesion molecules) has been proposed as a tool for tracing cancer spatiotemporal dynamics. Methods A mathematical model was established to simulate cancer cell migration. Human uterine leiomyoma specimens, in vitro cell migration assay, quantitative real-time PCR, western blotting, dynamic viscosity, and an in vivo C57BL6 mouse model were used to verify the predictive findings of our model. Results The return to origin probability (RTOP) and its related CAM expression ratio in tumors, so-called "tumor self-seeding", gradually decreased with increased tumor size, and approached the 3D Pólya random walk constant (0.340537) in a periodic structure. The biphasic pattern of cancer cell migration revealed that cancer cells initially grew together and subsequently began spreading. A higher viscosity of fillers applied to the cancer surface was associated with a significantly greater inhibitory effect on cancer migration, in accordance with the Stokes-Einstein equation. Conclusion The positional probability and cell-CAM-ECM interface (module) in the fractal framework helped us decipher cancer spatiotemporal dynamics; in addition we modeled the methods of cancer control by manipulating the microenvironment plasticity or inhibiting the CAM expression to the Pólya random walk, Pólya constant.

The aim of this study was to evaluate the effects of auricular acupressure on relieving menstrual symptoms and decreasing nitric oxide (NO) for women with primary dysmenorrhea.This was a randomized clinical trial comparing the effects of auricular acupressure by seed-pressure method and placebo adhesive patch.Settings included colleges in northern and central Taiwan.Serum CA-125 testing was used as a screening test for primary dysmenorrhea (35 mg/dL). The study included 36 college females randomized to acupressure group, 35 to control group.The acupressure group received auricular acupressure by seed-pressure method on liver (CO12), kidney (CO10), and endocrine (CO18) acupoints. The control group had a plain adhesive patch placed on the same acupoints with no seed attached. Acupressure protocol included massaging 15 times on each acupoint, 3 times a day, for a total of 20 days.Primary: Short-form Menstrual Distress Questionnaire (MDQs). Secondary: blood sample of NO. Assessments of MDQs and NO were performed at baseline and within the first 2 days of their next menses (after completion of 20 days of acupressure).In the acupressure group, the overall menstrual symptoms (95% confidence interval [CI] = -49.8 to -6.5, effect size [ES] = 0.43, p = 0.01) and two subscales, menstrual pain (95% CI = -16.4 -to -2.2, ES = 0.45, p = 0.01) and negative affects (95% CI = -11.9-2.0, ES = 0.38, p = 0.04), revealed that menstrual symptoms decreased significantly after auricular acupressure by the seed-pressure method. The ES for the MDQs were in favor of the auricular acupressure by seed-pressure method. NO level increased in the acupressure group, although this difference did not achieve statistical significance (p0.05).This study supports the effects of auricular acupressure by seed-pressure method in improving menstrual symptoms, and offers a noninvasive complementary therapy for women with primary dysmenorrhea.

Effects of maternal eating behaviors and attitudes, maternal feedback to daughter about weight issues, mother-daughter relationship closeness, media influences, and mothers' perceptions of daughters shape on daughters' body image and eating pathology were examined using 91 pairs of mothers and college-aged daughters. Hierarchical multiple regressions using daughters' BMI as the first step were separately performed for daughters' body image and eating pathology. Variables predictive of daughters' body image included negative feedback from mother, mother's disapproval of daughter's figure, and mothers' eating behaviors and attitudes as perceived by daughters. A similar pattern was found for daughters' eating pathology scores with the addition of mothers' tendency to internalize media messages regarding thinness and beauty significantly adding to the prediction. Maternal influence through modeling may be best assessed by using the daughters' perceptions of their mothers because this corresponds to what the daughter was aware of in their mothers' eating attitudes and behaviors. Negative feedback from mothers about daughters' figures and eating patterns significantly increased daughters' difficulties in these areas. Mothers who showed a greater internalization of media messages about thinness were most likely to have daughters with eating pathologies.

The Cox model with a gene effect for age at onset was introduced and studied by Li, Thompson and Wijsman. We study the nonparametric maximum likelihood estimation of the gene effect and the regression coefficient in this model. We indicate conditions under which the parameters are identifiable and the nonparametric maximum likelihood estimate is consistent and asymptotically normal. We also apply the theory of observed profile information to obtain a consistent estimate of the asymptotic variance. Besides providing theoretical support for Li et al., our work provides an alternative approach to the numerical methods in this model.

We conducted three studies to evaluate further the reliability and construct validity of a new self-report instrument, the Pain Distress Inventory (PDI; Osman et al., 2003, The Pain Distress Inventory: Development and initial psychometric properties, J. Clin. Psychol. 59: 767–785). In Study I, exploratory and confirmatory factor analytic results confirmed the replicability of the four-factor oblique solution of the PDI in a mixed sample of students and nonstudents. We also found strong evidence for criterion-related validity of scores on this instrument. In Study II, multisample analyses results found further evidence for equivalence of structure of the PDI across African American and Caucasian young adults. Ethnic and gender group differences were obtained on two of the PDI scale scores. Internal consistency reliability estimates on the PDI total and scale scores were good in both Studies I and II. In Study III, additional analyses of internal consistency and known-groups validity established strong support for construct validity of the PDI.

The goal of this research was to evaluate the roles of calpains and their interactions with the proteasome and the lysosome in degradation of individual sarcomeric and cytoskeletal proteins in cultured muscle cells. Rat L8-CID muscle cells, in which we expressed a transgene calpain inhibitor (CID), were used in the study. L8-CID cells were grown as myotubes after which the relative roles of calpain, proteasome and lysosome in total protein degradation were assessed during a period of serum withdrawal. Following this, the roles of proteases in degrading cytoskeletal proteins (desmin, dystrophin and filamin) and of sarcomeric proteins (alpha-actinin and tropomyosin) were assessed. Total protein degradation was assessed by release of radioactive tyrosine from pre-labeled myotubes in the presence and absence of protease inhibitors. Effects of protease inhibitors on concentrations of individual sarcomeric and cytoskeletal proteins were assessed by Western blotting. Inhibition of calpains, proteasome and lysosome caused 20, 62 and 40% reductions in total protein degradation (P0.05), respectively. Therefore, these three systems account for the bulk of degradation in cultured muscle cells. Two cytoskeletal proteins were highly-sensitive to inhibition of their degradation. Specifically, desmin and dystrophin concentrations increased markedly when calpain, proteasome and lysosome activities were inhibited. Conversely, sarcomeric proteins (alpha-actinin and tropomyosin) and filamin were relatively insensitive to the addition of protease inhibitors to culture media. These data demonstrate that proteolytic systems work in tandem to degrade cytoskeletal and sarcomeric protein complexes and that the cytoskeleton is more sensitive to inhibition of degradation than the sarcomere. Mechanisms, which bring about changes in the activities of the proteases, which mediate muscle protein degradation are not known and represent the next frontier of understanding needed in muscle wasting diseases and in muscle growth biology.

The goal of this study was to develop an inducible gene expression system to assess functions of specific proteins in differentiated cultured skeletal muscle. We utilized and modified the ecdysone inducible system because others have used this system to express exogenous genes in vitro and in transgenic animals. A limitation of the commercially-available ecdysone system is its constitutive expression in all tissues. Hence, its application in vivo would result in expression of a cloned gene in undifferentiated and differentiated tissues. To target its expression to muscle, we removed the constitutively-active CMV promoter of pVgRXR and replaced it with a skeletal muscle alpha-actin promoter so that the regulatory features of the system would be expressed in differentiated muscle cells. We transfected our newly designed expression system into L8 muscle myoblasts and established stable cell lines via antibiotic selection. We determined that reporter gene activity was induced by ponasterone A in myotubes, a differentiated muscle phenotype, but not in myoblasts (undifferentiated cells). This proved the validity of the concept of an inducible muscle-specific expression system. We then determined that beta-galactosidase expression was dependent upon the dose of ponasterone A and duration of exposure to inducer. This creates potential to regulate both the level of expression and duration of expression of a cloned gene in differentiated muscle.

Flaviviruses comprise a positive-sense RNA genome that replicates exclusively in the cytoplasm of infected cells. Whether flaviviruses require an activated nuclear factor(s) to complete their life cycle and trigger apoptosis in infected cells remains elusive. Flavivirus infections quickly activate nuclear factor kappa B (NF-κB), and salicylates have been shown to inhibit NF-κB activation. In this study, we investigated whether salicylates suppress flavivirus replication and virus-induced apoptosis in cultured cells. In a dose-dependent inhibition, we found salicylates within a range of 1 to 5 mM not only restricted flavivirus replication but also abrogated flavivirus-triggered apoptosis. However, flavivirus replication was not affected by a specific NF-κB peptide inhibitor, SN50, and a proteosome inhibitor, lactacystin. Flaviviruses also replicated and triggered apoptosis in cells stably expressing IκBα-ΔN, a dominant-negative mutant that antagonizes NF-κB activation, as readily as in wild-type BHK-21 cells, suggesting that NF-κB activation is not essential for either flavivirus replication or flavivirus-induced apoptosis. Salicylates still diminished flavivirus replication and blocked apoptosis in the same IκBα-ΔN cells. This inhibition of flaviviruses by salicylates could be partially reversed by a specific p38 mitogen-activated protein (MAP) kinase inhibitor, SB203580. Together, these results show that the mechanism by which salicylates suppress flavivirus infection may involve p38 MAP kinase activity but is independent of blocking the NF-κB pathway.

Objectives were to investigate the role of the proteasome and m -calpain to muscle cell differentiation. Accordingly, we investigated the effects of lactacystin, a proteasome inhibitor, and calpain inhibitor-II (CI-II) on L8 muscle cell differentiation and assessed concentrations of proteasomal and calpain subunit mRNAs during differentiation. L8 myoblasts were induced to differentiate by culturing in mitogen-depleted medium. To assess the importance of the proteasome and calpain to differentiation, we examined effects of lactacystin and CI-II on creatine kinase (CK) activity. In the absence of inhibitor, CK activity was detectable within 48 h of mitogen depletion and myotubes were formed. Addition of lactacystin or CI-II to cultures drastically reduced CK activity and prevented formation of myotubes. Hence, proteasome and calpain are both necessary for differentiation. In order to identify which proteasomal subunits were regulated during differentiation, we examined the concentrations of two 20S core subunits (C8 and C9) and three 22S ATPases (MSS1, S4 and TBP1) during differentiation. Concentrations of m -calpain and β -tubulin mRNAs were also assessed. Differentiation was associated with slight increases (ca. 30%) in concentrations of mRNAs encoding the proteasomal 20S core subunits (C8 and C9) and with large increases (approximately 2-fold) in mRNAs encoding the regulatory subunit ATPases. m -calpain mRNA concentration also increased two-fold following mitogen depletion. β -tubulin mRNA concentration remained unchanged early in the differentiation process and thereafter declined. Of interest, changes in proteasomal and m -calpain mRNAs occurred within 6–24 h of mitogen depletion (i.e., at least 24–36 h prior to detectable changes in creatine kinase activity). These results indicate that changes in expression of proteasome and calpains subunits occur early in the differentiation process. These changes may be required for the normal course of differentiation to proceed. Differentiation is associated with larger changes in proteasomal ATPase mRNAs than in 20S core particle mRNAs indicating that either turnover rates of the 22S ATPase subunits are more rapid in differentiating cells than of the 20S core particles or that functions of the regulatory subunits become more important during muscle cell differentiation.