Publications by authors named "Mark A Richardson"

Currently, diagnostic medicine uses a multitude of tools ranging from ionising radiation to histology analysis. With advances in piezoelectric crystal technology, high-frequency ultrasound imaging has developed to achieve comparatively high resolution without the drawbacks of ionising radiation. This research proposes a low-cost, non-invasive and real-time protocol for informing photo-therapy procedures using ultrasound imaging.

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Human skin equivalents (HSEs) are three-dimensional living models of human skin that are prepared in vitro by seeding cells onto an appropriate scaffold. They recreate the structure and biological behaviour of real skin, allowing the investigation of processes such as keratinocyte differentiation and interactions between the dermal and epidermal layers. However, for wider applications, their optical and mechanical properties should also replicate those of real skin.

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Objective: Studies examining cross-sectional associations between age at marijuana initiation and memory deficits yield mixed results. Because longitudinal data are sparse, controversy continues regarding whether these deficits reflect premorbid risk factors or sequelae of early marijuana initiation; here, we examine this question in a community sample followed since birth.

Method: Masked examiners administered four subtests of the Wide Range Assessment of Memory and Learning (WRAML/WRAML2) from childhood until young adulthood to 119 urban, predominantly African American participants.

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Retrospective recall-based measures administered to adults, like the Childhood Trauma Questionnaire (CTQ), are commonly used to determine experiences of childhood trauma in the home. However, the CTQ has not been compared with prospective measures of childhood violence exposure, whether at home or in the community. We evaluated the relationships between young adults' responses to the CTQ and their prospective self-reports of exposure to violence in childhood and adolescence.

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The present study examined the relationship between characteristics associated with personality disorders, substance use, and HIV risk among adults with a history of serious mental illness. Participants included 103 adults with antisocial or borderline personality disorder, serious mental illness, and recent HIV risk behavior. The sample was predominately male (64%), diverse (42% African American and 13% Hispanic), and homeless/marginally housed (76%).

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Background: Executive functioning (EF), an umbrella construct encompassing gradual maturation of cognitive organization/management processes, is important to success in multiple settings including high school. Intrauterine tobacco exposure (IUTE) correlates with negative cognitive/behavioral outcomes, but little is known about its association with adolescent EF and information from real-life contexts is sparse. We evaluated the impact of IUTE on teacher-reported observations of EF in urban high school students controlling for covariates including other intrauterine and adolescent substance exposures.

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This manuscript reviews research exploring the relationship between prenatal, perinatal, and adolescent exposure to marijuana and aggressive behavior, including physical aggression. Areas of inquiry include animal research, as well as human research, on prenatal exposure and on marijuana use during adolescence. Potential psychosocial and psychopharmacological mechanisms are identified, as well as relevant confounds.

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During the cocaine epidemic of the 1980s and early 1990s, many expressed fears that children with intrauterine cocaine exposure (IUCE) would grow up to be unusually violent. The present study examines the relationship of caregiver reports of school-age children's aggressive behavior with IUCE and postnatal exposure to violence. Respondents were 140 low-income, primarily African American children, ages 8-11, and each child's current primary caregiver from a longitudinal study evaluating potential long term sequelae of IUCE.

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Whether intrauterine cocaine exposure (IUCE) explains unique variance in psychiatric functioning among school age children, even after controlling for other biological and social risk factors, has not been fully delineated. As part of a longitudinal birth cohort study of children with and without IUCE, we conducted and analyzed data based on structured clinical interviews with 105 children (57% male) and their caregivers when the child was approximately 8.5 years old; 47% of the children had experienced IUCE.

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In this paper, we propose a novel image representation approach to tackle illumination variations in stereo matching problems. Images are mapped using their Fourier transforms which are convolved with a set of monogenic filters. Frequency analysis is carried out at different scales to account for most image content.

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The anticonvulsant topiramate not only decreases ethanol consumption in alcohol dependence (AD) but also may produce several adverse events including cognitive impairment. Zonisamide is a structurally related anticonvulsant that is a promising agent for the treatment of AD and may have greater tolerability than topiramate. This study evaluated the effects of zonisamide (400 mg/d) on alcohol consumption and its neurotoxic effects in subjects with AD.

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Individual differences in adolescents' executive functioning are often attributed either to intrauterine substance exposure or to adolescents' own substance use, but both predictors typically have not been evaluated simultaneously in the same study. This prospective study evaluated whether intrauterine drug exposures, the adolescents' own substance use, and/or their potential interactions are related to poorer executive functioning after controlling for important contextual variables. Analyses were based on data collected on a sample of 137 predominantly African-American/African Caribbean adolescents from low-income urban backgrounds who were followed since their term birth.

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Objectives: The objectives of this study are to assess the tolerability and efficacy of the anticonvulsant zonisamide in an open label trial of the treatment of alcohol dependence.

Methods: In this trial, zonisamide (400-mg daily) was administered to alcohol-dependent subjects (ADS) (n = 16) over 13 weeks. The mean daily consumption of standard alcoholic drinks and performance on a verbal fluency task, the COWAT, and on a measure of attention and visuomotor speed, the DSMT were assessed, and the occurrence of adverse events was monitored weekly.

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Neuropsychological (NP) impairment is multiply determined among HIV-infected and HIV-uninfected individuals who are also dually diagnosed with depression and who use illicit substances. The purpose of the present study was to assess the impact of HIV status, depression, and problematic substance use on NP performance. A total of 160 opiate-dependent outpatients undergoing methadone maintenance (80 HIV-infected, 80 HIV-uninfected) completed diagnostic and NP evaluations.

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Objective: The purpose of this study is to examine the effects of zonisamide on ethanol self-administration and subjective effects in risky drinkers using a human laboratory paradigm.

Method: We conducted a double-blind, placebo-controlled study of the effects of zonisamide 100 mg on ethanol self-administration and urge to drink in risky drinkers (N = 10) ( [1] ).

Result: During the second hour of a 2-hour self-administration session ethanol consumption was 50% lower in the zonisamide group as compared to the placebo group.

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This study assessed the frequency of neuropsychological impairment and its relationship to adherence in a sample of HIV-infected injection drug users (IDUs) in treatment. One hundred eight participants recruited between September 2006 and October 2008 completed psychodiagnostic and neuropsychological assessments and monitored HAART adherence over a 2-week period via the use of Medication Event Monitoring System (MEMS) electronic pill caps and self-report. Assessment of concurrent functioning included clinician-rated scales of depression and substance use severity, and a battery of neuropsychological tests.

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Administration of activated protein C (APC) protects from renal dysfunction, but the underlying mechanism is unknown. APC exerts both antithrombotic and cytoprotective properties, the latter via modulation of protease-activated receptor-1 (PAR-1) signaling. We generated APC variants to study the relative importance of the two functions of APC in a model of LPS-induced renal microvascular dysfunction.

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This study assessed adherence to HAART among 67 HIV-infected adults, and the degree to which gender and psychological factors-including depression, drug and alcohol use, quality of life, and medication side effects-influenced adherence. Although overall adherence was greater than rates reported in similar studies, no significant difference in adherence was observed between men and women in the present sample. Medication side effects were a significant predictor of non-adherence in the sample at large and among women in particular, while alcohol dependence was a significant predictor of non-adherence only in women.

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The protein C (PC) pathway plays an important role in vascular and immune function, and acquired deficiency during sepsis is associated with increased mortality in both animal models and in clinical studies. However, the association of acquired PC deficiency with the pathophysiology of lung injury is unclear. We hypothesized that low PC induced by sepsis would associate with increased pulmonary injury and that replacement with activated protein C (APC) would reverse the activation of pathways associated with injury.

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Previous research has been inconsistent in documenting a strong relationship between depression and HIV/AIDS, although a recent meta-analysis of studies examining this issue indicates that rates of depression are modestly higher for this population. For the current study, conducted from 2001-2004, we sought to examine rates and types of depressive symptoms in a cohort of patients receiving HIV care at two urban medical centers. These patients were participants in an intervention study examining adherence and mental health in persons triply diagnosed with psychiatric disorders, substance use disorders, and HIV/AIDS.

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Unlabelled: Background- APC is an antithrombotic and antiinflammatory serine protease that plays an important role in vascular function. We report that APC can suppress the proapoptotic mediator TRAIL in human umbilical vein endothelial cells, and we have investigated the signaling mechanism.

Methods And Results: APC inhibited endothelial TRAIL expression and secretion and its induction by cell activation.

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Inducible nitric-oxide synthase (iNOS) plays a central role in the regulation of vascular function and response to injury. A central mediator controlling iNOS expression is transforming growth factor-beta (TGF-beta), which represses its expression through a mechanism that is poorly understood. We have identified a binding site in the iNOS promoter that interacts with the nuclear heterodimer TCF11/MafG using chromatin immunoprecipitation and mutation analyses.

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Activated protein C (APC) is an important modulator of vascular function that has antithrombotic and anti-inflammatory properties. Studies in humans have shown modulation of endotoxin-induced hypotension by recombinant human APC, drotrecogin alfa (activated), however, the mechanism for this effect is unclear. We have found that APC suppresses the induction of the potent vasoactive peptide adrenomedullin (ADM) and could downregulate lipopolysaccharide (LPS)-induced ADM messenger RNA (mRNA) and nitrite levels in cell culture.

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Protein C (PC) plays an important role in vascular function, and acquired deficiency during sepsis is associated with increased mortality in both animal models and in clinical studies. This study explored the consequences of PC suppression on the kidney in a cecal ligation and puncture model of polymicrobial sepsis. This study shows that a rapid drop in PC after sepsis is strongly associated with an increase in blood urea nitrogen, renal pathology, and expression of known markers of renal injury, including neutrophil gelatinase-associated lipocalin, CXCL1, and CXCL2.

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