About

Mark Richardson is a Clinical Associate Professor in the Department of Psychological & Brain Sciences at Boston University. His primary research activities focus on the cognitive and affective sequelae of HIV/AIDS and their impact on adherence to treatment regimens. His additional research interests include the neurobehavioral consequences of acute and chronic substance abuse, depression, and closed head injury. He also investigates the impact of ethnicity and culture on psychological assessment and clinical judgment, as well as the individual and institutional factors that influence access to and utilization of mental health services. Dr. Richardson earned his PhD from the University of California, Los Angeles, and is actively involved in research and teaching within his field.

Research topics

• Biochemistry
• Epistemology
• Combinatorial chemistry
• Medicine
• Materials science
• Nanotechnology
• Chromatography
• Organic chemistry
• Surgery
• Chemistry

Selected publications

• Industry Viable Electrochemical DNA Detection Sensor Architecture Via a Stem-Loop Methylene Blue Redox Reporter and Rapid in Situ Probe Mobilization Method

  Meeting abstracts/Meeting abstracts (Electrochemical Society. CD-ROM) · 2021

  • Combinatorial chemistry
  • Materials science
  • Nanotechnology

  Pharmacogenomics is one of the endeavours in the modern acute health care sector due to the complexity of the drug reactions associated with the patients' genetic markers[1]. Therefore, the availability of patient pharmacogenetic marker testing at the point-of-care (POC) setting will help the clinicians to prescribe and personalize the medication to ensure maximum efficiency with minimal adverse drug reactions (ADR). In this regard, we focused on developing a HLA-B*15:02 pharmacogenetic biomarker testing known to cause specific ADRs for Carbamazepine[2]. In this study, disposable screen-printed electrodes (SPE) as the planar sensor surfaces and a sequence-specific stem-loop probe modified with a methylene blue redox (MB) reporter was used to detect the targeted DNA sequence of HLA-B*15:02. The oligo probe with MB reporter at the 3′ end was designed to incorporate 25 nucleotides to detect the specific region. The disulphide-reducing reagent, Tris(2-carboxyethyl) phosphine hydrochloride was introduced to reduce the S-S bond of the oligo probe. The probe immobilization on the working electrode area was performed using the fully automated non-contact dispensing system sciFLEXARRAYER SX by dispensing an array of droplets of 50 µM probe mixture into accurate positioning of the gold working electrode area of SPEs (220AT DropSens). Around 20 SPEs were loaded, and probes were printed during a single batch processing task. Two printing runs were performed, and a total of N=30 biosensors were used in the experimental procedure. The electrochemical behaviour of the sensor was studied by performing the square wave voltammetry (SWV) measurements from -0.4 V to -0.1 V, with a modulation amplitude of 0.02 V and frequency of 25 Hz at a scan rate of 0.026 V/s (Autolab-PGSTAT204). The target hybridization time was fixed at 30 minutes. The p-values ≤ 0.05 was considered statistically significant. The SWV measurements on the sensors with 75 µl, 1X PBS solution (Baseline) showed a well-defined peak at -0.31 V with the standard deviation (SD) of 0.004 V (N total =30) which is consistent with the potential of the MB redox moiety. The statistical t-test has been shown that no statistical significance (p=0.1760) between the two printing runs with the peak heights of 640.5 nA ± 151.2 nA (SD). Upon target hybridization, measured peak heights showed that (a) 152.0 nA ± 23.3 nA for the 50 µM Positive control (oligo with the sequence complementary to the probe), (b) 231.8 nA ± 54.8 nA for the 50 µM Negative control (oligo with the non-complementary sequence to the probe), and (c) 226.2 nA ± 93.2 nA for the Blank-oligo free sensors. This shows ~34% signal suppression in Positive control hybridized sensors, whereas insignificance difference between the Negative and Blank samples hybridized sensors. Furthermore, statistical analysis (one-way ANOVA) show that a statistical significance (p=0.0250) for the Positive vs. Negative, a statistical significance (p=0.0388) for the Positive vs. Blank sample, and no statistical significance (p=0.9793) for the Negative vs. Blank sample. These results confirmed that a complementary target binding event in the stem-loop probe results in a significant signal decrease and the possibility of using this 'signal-off biosensor architecture in detecting HLA-B*15:02 pharmacogenetic biomarker testing platform. It was found that only 6 µl probe mixture was required to cover one sensor. Accordingly, the calculated probe surface density was equivalent to ~1.43×10 15 molecules/cm 2 , which will be 3 order of magnitudes higher than the typical probe surface density (~10 12 ) of biosensors[3]. This high level of probe surface density on the sensors was achieved by printing a high concentration of low volume of redox probes. This will not be possible in the typical wet bench probe immobilization methods. Also, it showed a significantly higher level of faradaic current generated in the biosensor and clear differentiation of the targets. Therefore, this work showcases encouraging results of biosensor architecture, rapid probe immobilization method, the possibility of using the ultra-low volume of probe reagents, and high-throughput productions. This suggested that further development of this pharmacogenetic biomarker testing platform will enhance the technical feasibility and enable the transition of this biosensor from the research to industry. Acknowledgements This work used the Melbourne Centre for Nanofabrication (MCN) in the Victorian Node of the NCRIS-enabled Australian National Fabrication Facility (ANFF). References FDA. Table of Pharmacogenomic Biomarkers in Drug Labeling . Available from: https://www.fda.gov/drugs/science-and-research-drugs/table-pharmacogenomic-biomarkers-drug-labeling . Soraya, G.V., et al., An interdigitated electrode biosensor platform for rapid HLA-B*15:02 genotyping for prevention of drug hypersensitivity. Biosens Bioelectron, 2018. 111 : p. 174-183. Ricci, F., et al., Effect of molecular crowding on the response of an electrochemical DNA sensor. Langmuir, 2007. 23 (12): p. 6827-6834.

  PublisherDOI

• Palliative Management of Nonoperative Femoral Neck Fractures With Continuous Peripheral Indwelling Catheters: Case–Control Series

  Geriatric Orthopaedic Surgery & Rehabilitation · 2019-01-01 · 7 citations

  articleOpen access

  Introduction: This case–control study evaluates the success of indwelling pain catheters in nonoperatively treated femoral neck fractures (FNFs) for end-of-life pain management. Methods: Patients older than 65 years with nonoperatively treated FNFs were retrospectively identified at a level 1 trauma center between March 2012 and September 2015. Twenty-three received indwelling continuous peripheral pain catheters (experimental) and 10 received traditional pain control modalities (control). Pain scores 24 hours before/after pain management interventions, ambulation status at admission and discharge, mortality at 30 days/1 year, and length of hospital stay (LOS) were compared between treatment groups. Results: The experimental and control groups were similar with respect to demographics, differing only in pre-fracture ambulatory status ( P = .03). The 30-day mortality was 52% versus 50% (odds ratio, OR: 1.1 [95% confidence interval, CI: 0.25-4.82], P = .99) and 1-year mortality was 87% versus 80% (OR: 1.67 [95% CI: 0.23-11.9], P = .63) for experimental and control groups, respectively. The LOS did not statistically significantly differ for experimental and control groups (5.3 ± 3.56 days vs 3.8 ± 1.81 days, P = .15), respectively. The experimental group experienced twice the improvement in ambulation status (1.0 ± 0.56 vs 0.5 ± 0.71, P = 0.03) and greater improvement in pain scores (4.5 ± 2.19 vs 1.2 ± 2.72, P = .002). Discussion: Operative management of FNFs may not be indicated in patients with advanced age and comorbidities. Regardless, these patients require pain palliation and early mobilization while minimizing hospital LOS and opiate consumption. Conclusion: This case–control study demonstrates significant improvement in both pain level and ambulatory status for patients treated with indwelling continuous peripheral catheters. Future studies should further evaluate with a larger sample size; however, this study provides an excellent launching point for palliative management of this complex population.

  PublisherOA PDFDOI

• Do Differences in Learning Performance Precede or Follow Initiation of Marijuana Use?

  Journal of Studies on Alcohol and Drugs · 2019-01-01 · 6 citations

  articleOpen access

  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. Multivariable generalized estimated equation models measured longitudinal trajectories of learning. Participants were grouped as never users (n = 26), later initiators (≥16 years old; n = 31), and earlier initiators of marijuana use (n = 62). RESULTS: Marijuana onset groups did not significantly differ on WRAML scaled scores or IQ in childhood, nor did they differ on WRAML scaled scores in adolescence. On most WRAML2 subtests, these groups did not significantly differ in young adulthood after taking into account sex and childhood IQ. However, on Story Memory, later initiators attained higher scaled scores in young adulthood, even after including additional covariates of anxiety, depression, postsecondary education, past-month marijuana use, and past-week high-risk drinking. They showed a significantly more positive trajectory than never users that was driven by within-group improvement after adolescence. Earlier initiators showed within-group decline in Story Memory after adolescence. CONCLUSIONS: Differences in learning following earlier initiation of marijuana use may not be solely attributable to premorbid deficits.

  PublisherOA PDFDOI

• 99mTechnetium and methylene blue guided pulmonary nodules resections: preliminary British experience

  Journal of Thoracic Disease · 2018-02-01 · 27 citations

  articleOpen access

  BACKGROUND: Subcentimetre pulmonary nodules can be challenging to locate either during video-assisted thoracoscopic surgery (VATS) or by open techniques. In an era of increasing computed tomography scan availability the number of nodules that are identified that are suspicious for malignancy is rising, and thoracic surgeons require a reliable method to locate these nodules intraoperatively. METHODS: Our aim was to evaluate, for the first time in the UK, resection of pulmonary nodules using radioactive dye labelling. Local research ethics approval was obtained and the study was submitted to the Integrated Research Application System (IRAS). All data were prospectively collected in our dedicated thoracic surgical database and analyzed at the conclusion of the study. This represents a consecutive series of patients, from January 2016 and until April 2017, who underwent this procedure at our institution: James Cook University Hospital, Middlesbrough, United Kingdom. The primary outcome measured was successful resection rate of the target nodules. RESULTS: Twenty-three patients underwent radiolabeled excision of pulmonary nodules, their average age was 61 years (range, 28-79 years), 13 women and 10 men. The average maximum diameter of the nodule was 8 mm (range, 3-16 mm). All patients underwent successful excision of the target lesion (success rate 100%). One patient (4.3%) sustained pneumothorax following the CT-guided injection of the radio-labelled dye and this required chest drainage prior to general anesthesia. CONCLUSIONS: We conclude that technetium guided pulmonary nodule resection is a very reliable method for localization and resection of subcentimetre nodules which may be otherwise be difficult to identify.

  PublisherOA PDFDOI

• Radio-guided pulmonary nodules resection: preliminary British experience

  ASVIDE · 2018-01-01 · 1 citations

  article
  PublisherDOI

• Childhood Trauma Questionnaire (CTQ) correlations with prospective violence assessment in a longitudinal cohort.

  Psychological Assessment · 2018-05-31 · 83 citations

  articleOpen access

  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. Participants were 127 (93% African American, 47% male) urban young adults in a longitudinal birth cohort study examining effects of prenatal substance exposure and environmental factors on development. Participants completed the Violence Exposure Scale for Children-Revised (VEX-R), a 21-item self-report measure of experience of/witness to interpersonal violence, administered face to face at 9, 10, and 11 years using cartoon pictures, and via audio-computer assisted self-interview at 12, 14, and 16 years. Participants also completed the CTQ, a 28-item, 5-scale screening measure, during a young-adult follow-up (ages 18-23). Using Pearson Correlation coefficients, VEX-R total scores significantly correlated with the sum of CTQ scales, r = .33, p < .01, and 3 (physical, emotional, and sexual abuse) of the 5 CTQ subscales, showing a moderate linear association. This study suggests that the CTQ serves as a reasonable retrospective assessment of prospectively ascertained childhood trauma exposure. The differences may be accounted for by disparities in domains assessed. (PsycINFO Database Record

  PublisherDOI

• Intrauterine exposure to tobacco and executive functioning in high school

  Drug and Alcohol Dependence · 2017-05-10 · 11 citations

  article
  PublisherDOI

• HIV Risk, Substance Use, and Personality Characteristics among Adults with History of Serious Mental Illness

  Behavioral Medicine · 2017-07-03 · 3 citations

  article

  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%). In order to examine the relationship between personality characteristics and risk we constructed a risk index comprising key symptoms of antisocial and borderline personality disorders, namely; impulsivity, affective instability, and disregard for safety of self/others. Contrary to our primary hypotheses, risk index scores did not predict HIV risk behavior and substance abuse did not mediate this risk. Exploratory analyses did reveal that women engaged in significantly more risk behaviors than their male counterparts and that risk scores were a significant predictor of total sex acts for women but not men. In addition, increased emotional dysregulation was a significant predictor of condomless sex acts for women but not men. Finally, recent alcohol use and increased impulsivity was associated with more condomless oral sex for men and women. These results suggest the relationship among serious mental illness, personality disorder, substance abuse, and gender is complex and merits further study.

  PublisherDOI

• Sleep Apnea in Children History and Physical Exam

  2016-04-19

  book-chapter1st authorCorresponding

  Polysomnography is the “gold standard” for diagnosis of sleep disordered breathing. An accurate history and physical exam can identify patients at risk for sleep disorders and possible complications of surgery. Primary snoring and obstructive sleep apnea (OSA) represent a spectrum of disorders indicating increased upper airway resistance to airflow. It should be noted that a small percentage of patients with OSA may have physiologic changes, such as cardiomegaly and pulmonary hypertension, due to the transient but repeated hypoxia that occurs during sleep and that accompanies the disease. A history of difficulty with swallowing due to enlarged tonsils, pharyngeal speech, or nasal obstruction should lead to questions about sleep and the possibility of apnea. There seem to be increased rates of OSA in African American children, and Asian children may also be predisposed to OSA. Although Mallampati scores are not currently well correlated with OSA in children, they are a general index for anatomic crowding associated with difficult intubation.

  PublisherDOI

• Prenatal, perinatal, and adolescent exposure to marijuana: Relationships with aggressive behavior

  Neurotoxicology and Teratology · 2016-06-25 · 24 citations

  review
  PublisherDOI

Frequent coauthors

• Andrew F. Inglis

  34 shared

• Paul M. Mendelman

  Takeda (United States)

  28 shared

• Newton O. Duncan

  Baylor College of Medicine

  28 shared

• Mark A. Del Beccaro

  Seattle Children's Hospital

  27 shared

• Carla R. Clausen

  25 shared

• Terrence L. Stull

  25 shared

• Brian W. Grinnell

  Eli Lilly (United States)

  21 shared

• Deborah A. Frank

  Boston Medical Center

  20 shared

Labs

• Developmental SciencePI

Education

• Ph.D.

  University of California, Los Angeles