Publications by authors named "Kevin Knight"

87 Publications

An evaluation of StaySafe, a tablet app to improve health risk decision-making among people under community supervision.

J Subst Abuse Treat 2021 May 14;130:108480. Epub 2021 May 14.

Texas Christian University, Institute of Behavioral Research, TCU Box 298740, Fort Worth, TX 76129, USA. Electronic address:

Background: A self-administered tablet app, StaySafe, helps people under community supervision to make better decisions regarding health risk behaviors, especially those linked to HIV, viral hepatitis, and other sexually transmitted infections. The multi-session StaySafe design uses an interactive, analytical schema called WORKIT that guides users through a series of steps, questions, and exercises aimed at promoting critical thinking about health risks associated with substance use and unprotected sex. Repetition of the WORKIT schema is designed to enhance procedural memory that can be rapidly accessed when individuals are faced with making decisions about risky behaviors.

Methods: A total of 511 participants under community supervision in community and residential treatment settings from three large Texas counties completed consent forms and baseline surveys, followed by randomization to one of two conditions: 12 weekly StaySafe sessions or standard practice (SP). The study also asked participants to complete a follow-up survey three months after baseline. Outcome measures included knowledge, confidence, and motivation (KCM) scales around HIV knowledge, avoiding risky sex, HIV services, and reducing health risks; decision-making; and reports of talking about issues such as making better decisions, avoiding HIV risks, and HIV prevention or treatment with others (probation officers, counselors, trusted friend or advisor, or family members).

Results: Participants in both community and residential settings voluntarily completed multiple StaySafe sessions, with those in the residential settings completing more sessions. When compared with SP participants, StaySafe participants showed greater improvement in the KCM measures-HIV knowledge, avoiding sex risks, HIV services, and risk reduction skills. In addition, greater improvements in the KCM measures as well as an increased likelihood to discuss issues with others were associated with completing more StaySafe sessions.

Conclusion: These results suggest that the StaySafe app is a feasible and potentially effective tool for improving health risk reduction decision-making for individuals under community supervision.
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http://dx.doi.org/10.1016/j.jsat.2021.108480DOI Listing
May 2021

Linking criminal justice-involved individuals to HIV, Hepatitis C, and opioid use disorder prevention and treatment services upon release to the community: Progress, gaps, and future directions.

Int J Drug Policy 2021 May 18:103283. Epub 2021 May 18.

Yale School of Medicine, Section of Infectious Disease, AIDS Program, 135 College Street, Suite 323, New Haven, CT 06510, United States. Electronic address:

Improving HIV and Hepatitis C Virus (HCV) management among people involved in the criminal justice (CJ) system who use drugs, in particular those with opioid use disorder (OUD), requires effective approaches to screening, linkage, and adherence to integrated prevention and treatment services across correctional and community agencies and providers. This manuscript reviews the literature to explore gaps in HIV, Hepatitis C, and OUD prevention, treatment, and delivery cascades of care for persons involved in the CJ system. Specifically, we compare two models of linkage to prevention and treatment services: Peer/Patient Navigation (PN) wherein the PN links CJ-involved individuals to community-based infectious disease (ID) and substance use prevention and treatment services, and Mobile Health Units (MHU) wherein individuals are linked to a MHU within their community that provides integrated ID and substance use prevention and treatment services. The most notable finding is a gap in the literature, with few to no comparisons of models linking individuals recently released from the CJ system to integrated HIV, Hepatitis C, and OUD prevention and treatment and other harm reduction services. Further, few published studies address the geographical distinctions that affect service implementation and their effects on these substance use, ID and harm reduction care cascades. This manuscript makes specific recommendations to fill this gap through a detailed evaluation of PN and MHU linkage models to co-located and integrated HIV, Hepatitis C, and OUD prevention and treatment services across different communities within the U.S.
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http://dx.doi.org/10.1016/j.drugpo.2021.103283DOI Listing
May 2021

The Role of Personality Functioning on Early Drop out in Outpatient Substance Misuse Treatment.

Subst Use Misuse 2021 21;56(8):1119-1136. Epub 2021 Apr 21.

Institute of Behavioral Research, Texas Christian University, Fort Worth, TX, USA.

Background: Treatment initiation is a major factor contributing to positive outcomes, but the supporting literature remains limited. It is difficult to draw conclusions regarding predictors of dropout, and there is a need to target clients' major early attrition vulnerabilities. Despite empirically validated models for assessing personality, little is known about its role in the treatment process. Studies that have been conducted in this area have focused mainly on stable personality traits and provide conflicting evidence. The aim of this study is to examine to what extent service users' personality functioning are potential determinants of early drop out. A cross-sectional multi-site design examined the therapy process in a naturalistic setting in 5 outpatient preparation treatment centers with 210 service users. The current study adopts a contemporary dimensional-based framework, similar to the Alternative Model of Personality Disorder of the DSM-V and examines the role of characteristic adaptations (SIPP-118) on early drop out (CEST-Intake). From the broad spectrum of personality traits, only remained significant predictor of drop out. Higher dysfunctional levels in [OR] = 1.85, Wald =19.87, =.002, 95% CI [1.1, 1.9] as well as the facets Aggression , and were also predictors of early drop out, while and accounted for a significant amount of variance. These findings extend our knowledge of the predictive role of characteristic adaptations in treatment and suggest it may be important to assess these individual differences early on and to design personalized-informed interventions.
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http://dx.doi.org/10.1080/10826084.2021.1908358DOI Listing
June 2021

A universal allosteric mechanism for G protein activation.

Mol Cell 2021 04 25;81(7):1384-1396.e6. Epub 2021 Feb 25.

Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA. Electronic address:

G proteins play a central role in signal transduction and pharmacology. Signaling is initiated by cell-surface receptors, which promote guanosine triphosphate (GTP) binding and dissociation of Gα from the Gβγ subunits. Structural studies have revealed the molecular basis of subunit association with receptors, RGS proteins, and downstream effectors. In contrast, the mechanism of subunit dissociation is poorly understood. We use cell signaling assays, molecular dynamics (MD) simulations, and biochemistry and structural analyses to identify a conserved network of amino acids that dictates subunit release. In the presence of the terminal phosphate of GTP, a glycine forms a polar network with an arginine and glutamate, putting torsional strain on the subunit binding interface. This "G-R-E motif" secures GTP and, through an allosteric link, discharges the Gβγ dimer. Replacement of network residues prevents subunit dissociation regardless of agonist or GTP binding. These findings reveal the molecular basis of the final committed step of G protein activation.
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http://dx.doi.org/10.1016/j.molcel.2021.02.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8026646PMC
April 2021

Justice community opioid innovation network (JCOIN): The TCU research hub.

J Subst Abuse Treat 2021 Jan 15:108290. Epub 2021 Jan 15.

Texas Christian University, TX, USA. Electronic address:

Recognizing the current opioid crisis among justice-involved individuals and the need to intervene at the intersection of justice and community health, the JCOIN TCU hub study explores outcomes associated with a multi-level hybrid implementation approach. The study capitalizes on facilitated collaboration, training, and cross-system data sharing to leverage improvements in criminal justice (CJ) and community behavioral health (CBH) interagency collaboration. The goal is to improve local community public health and safety outcomes for reentering justice-involved individuals who have a history of (or are at risk for) using opioids. The study compares two implementation strategies: one (vertical) in which all units in a community are trained and begin the program simultaneously and another (horizontal) in which one lead-off unit in the community is trained as a prototype of the program, the prototype is tested and refined, and then the lead-off unit helps to train other units within the community. Specific aims are to 1) increase access to and retention in CBH and medications for opioid use disorder services; 2) improve outcomes associated with public health and safety; 3) compare two implementation strategies on systems-level outcomes designed to increase service initiation and receipt of implementation and services; and 4) examine the impact of these strategies on justice-involved individuals' outcomes. The study examines both implementation and implementation-effectiveness, seeking to answer the questions of which implementation strategy is most effective for rapid and sustainable uptake of evidence-based practices and for increasing service linkage and initiation, services retention, and improved opioid-related public health safety outcomes. The study uses a hybrid type 3 study design. The study's primary aim is to compare two implementation strategies and two interventions at two levels (client and system), with a secondary aim to assess client-level outcomes associated with the trial. The study design integrates 2 robust methodologies (stepped wedge and cluster randomized trial), and plans to include 18 research performance sites (communities) located in Texas, New Mexico, and Illinois. The study will contribute to the JCOIN network's effort to establish a national consortium of investigators examining promising strategies to enhance the capabilities and capacity of the justice system to more effectively address the opioid epidemic.
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http://dx.doi.org/10.1016/j.jsat.2021.108290DOI Listing
January 2021

Crystal and Electronic Structures of ANaIO Periodate Double Perovskites (A = Sr, Ca, Ba): Candidate Wasteforms for I-129 Immobilization.

Inorg Chem 2020 Dec 9;59(24):18407-18419. Epub 2020 Dec 9.

Department of Materials Science and Engineering, University of Sheffield, Sheffield S1 3JD, U.K.

The synthesis, structure, and thermal stability of the periodate double perovskites ANaIO (A= Ba, Sr, Ca) were investigated in the context of potential application for the immobilization of radioiodine. A combination of X-ray diffraction and neutron diffraction, Raman spectroscopy, and DFT simulations were applied to determine accurate crystal structures of these compounds and understand their relative stability. The compounds were found to exhibit rock-salt ordering of Na and I on the perovskite B-site; BaNaIO was found to adopt the 3 aristotype structure, whereas SrNaIO and CaNaIO adopt the 2/ hettotype structure, characterized by cooperative octahedral tilting. DFT simulations determined the 3 and 2/ structures of BaNaIO to be energetically degenerate at room temperature, whereas diffraction and spectroscopy data evidence only the presence of the 3 phase at room temperature, which may imply an incipient phase transition for this compound. The periodate double perovskites were found to exhibit remarkable thermal stability, with BaNaIO only decomposing above 1050 °C in air, which is apparently the highest recorded decomposition temperature so far recorded for any iodine bearing compound. As such, these compounds offer some potential for application in the immobilization of iodine-129, from nuclear fuel reprocessing, with an iodine incorporation rate of 25-40 wt%. The synthesis of these compounds, elaborated here, is also compatible with both current conventional and future advanced processes for iodine recovery from the dissolver off-gas.
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http://dx.doi.org/10.1021/acs.inorgchem.0c03044DOI Listing
December 2020

Self-reported antiretroviral therapy adherence and viral load in criminal justice-involved populations.

BMC Infect Dis 2019 Oct 29;19(1):913. Epub 2019 Oct 29.

Department of Internal Medicine, Section of Infectious Disease, Yale AIDS Program, Yale New Haven Hospital, Yale University School of Medicine, 135 College street, Suite 323, 20 York Street, New Haven, CT, 06510, USA.

Background: Self-reported antiretroviral therapy (ART) adherence measures that are associated with plasma viral load (VL) are valuable to clinicians and researchers, but are rarely examined among groups vulnerable to dropping out of care. One-seventh of all those living with HIV pass through incarceration annually and criminal-justice (CJ) involved people living with HIV (PLH) are vulnerable to falling out of care. We examined the association of self-reported ART adherence with VL in a criminal-justice sample compared to a routine-care sample.

Methods: Samples: We examined data from a multisite collaboration of studies addressing the continuum of HIV care among CjJ involved persons in the Seek, Test, Treat, and Retain cohort. Data pooled from seven CJ- studies (n = 414) were examined and compared with the routine-care sample from the Centers for AIDS Research Network of Integrated Clinical Systems' seven sites (n = 11,698).

Measures: In both samples, data on self-reported percent ART doses taken were collected via the visual analogue scale adherence measure. Viral load data were obtained by blood-draw.

Analysis: We examined the associations of adherence with VL in both cohorts using mixed effects linear regression of log-VL, and mixed effects logistic regression of binary VL (≥ 200 copies/mL) outcomes. Interactions by CD4 count and self-reported health status were also tested.

Results: Among the CJ sample, the coefficient for log-VL was - 0.31 (95% CI = - 0.43, - 0.18; P < 0.01) and that in the routine-care sample was - 0.42 (95% CI = - 0.45, - 0.38; P < 0.01). For the logistic regression of binary detectable VL on 10% increments of adherence we found the coefficient was - 0.26 (95% CI = - 0.37, - 0.14; P < 0.01) and in the routine-care sample it was - 0.38 (95% CI = - 0.41, - 0.35; P < 0.01). There was no significant interaction by CD4 count level in the CJ sample, but there was in the routine-care sample. Conversely, there was a significant interaction by self-reported health status level in the criminal-justice sample, but not in the routine-care sample.

Conclusions: The visual analogue scale is valid and useful to measure ART adherence, supporting treatment for CJ- involved PLH vulnerable to falling out of care. Research should examine adherence and VL in additional populations.
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http://dx.doi.org/10.1186/s12879-019-4443-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6819597PMC
October 2019

Structure and physical properties of SeCo Mn O.

J Phys Condens Matter 2019 Oct 28;31(39):395402. Epub 2019 Jun 28.

ISIS Neutron and Muon Source, Rutherford Appleton Laboratory, Chilton, Didcot OX11 0QX, United Kingdom.

We describe the high-pressure (4 GPa) high-temperature (∼1100 K) synthesis of the solid solution series SeCo Mn O (0  <  x  <  1) using HSeO and transition metal oxide mixtures sealed in Pt capsules. Neutron powder diffraction has been performed to determine progression of the structure across the solution. All samples crystallise with orthorhombic Pnma symmetry, and octahedral tilting is determined to increase with Mn content. SQUID magnetometry measurements were performed, and reveal that the Néel temperature shifts only by approximately 1 K over the series.
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http://dx.doi.org/10.1088/1361-648X/ab2db9DOI Listing
October 2019

High-Pressure Study of the Elpasolite Perovskite LaNiMnO.

Inorg Chem 2019 Jul 26;58(14):9016-9027. Epub 2019 Jun 26.

ISIS Neutron and Muon Source , Rutherford Appleton Laboratory , Chilton, Didcot OX11 0QX , U.K.

Here we report a high-pressure investigation into the structural and magnetic properties of the double perovskite LaNiMnO using neutron scattering over a temperature range of 4.2-300 K at ambient pressure and over a temperature range of 120-1177 K up to a maximum pressure of 6.6 GPa. X-ray diffraction was also used up to a maximum pressure of 64 GPa, over a temperature range of 300-720 K. The sample was found to exist in a mixed rhombohedral/monoclinic symmetry at ambient conditions, the balance of which was found to be strongly temperature- and pressure-dependent. Alternating current magnetometry and X-ray absorption near-edge structure measurements were made at ambient pressure to characterize the sample, suggesting that the transition-metal sites exist in a mixed Ni/Mn and Ni/Mn state at ambient temperature and pressure. Analysis of the magnetic properties of the sample shows that the Curie temperature can be enhanced by ∼12 K with 2 GPa applied pressure, but it is highly stable at pressures beyond this. We report a pressure-volume-temperature equation of state for this material over this combined temperature and pressure range, with an ambient temperature bulk modulus of ∼179(8) GPa. The previously reported transition from monoclinic to rhombohedral symmetry upon heating to 700 K is seen to be encouraged with applied pressure, transforming fully by ∼1.5 GPa. Raman spectroscopy data were collected up to ∼8 GPa and show no clear changes or discontinuities over the reported phase transition to rhombohedral symmetry or any indication of further changes over the range considered. The ambient-pressure Grüneisen parameter was determined to be = 2.6 with a Debye temperature of 677 K. The individual modal parameters at ambient temperature were also determined from the high-pressure Raman data.
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http://dx.doi.org/10.1021/acs.inorgchem.9b00404DOI Listing
July 2019

The role of physical and psychological health problems in the drug use treatment process.

J Subst Abuse Treat 2019 07 30;102:23-32. Epub 2019 Mar 30.

Institute of Behavioral Research, Texas Christian University, TCU Box 298740, Fort Worth, TX 76129, USA. Electronic address:

The role of physical and psychological health is examined as a predictor of client engagement in prison-based drug treatment. A treatment process model was expanded to include physical and mental health issues. The sample included 6009 offenders in prison-based drug treatment, comprised of 67% male, 26% African American, 51% white, and 22% Hispanic; average age was 34.6. Half reported "some physical health concerns" and mentioned a variety of ailments. A fifth reported moderate stress on the Kessler Psychological Distress Scale (K10) and 15% reported PTSD based on the PTSD Check List (PCL). Structural equation modeling was used to model treatment engagement in terms of demographics, physical health concerns, psychological distress, HIV risky behaviors, self-esteem, decision making, and treatment motivation. Two random samples were created, with one used for estimation and the other for cross-validation. The findings suggested physical health and HIV risky behaviors have effects on client engagement through psychological functioning, and that psychological functioning has direct effects on treatment engagement.
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http://dx.doi.org/10.1016/j.jsat.2019.03.011DOI Listing
July 2019

Treatment Retention Satisfaction, and Therapeutic Progress for Justice-Involved Individuals Referred to Community-Based Medication-Assisted Treatment.

Subst Use Misuse 2019 29;54(9):1461-1474. Epub 2019 Apr 29.

b Institute of Behavioral Research , Texas Christian University, Fort Worth, Texas, USA.

: Limited research has examined factors associated with medication-assisted treatment for justice-involved individuals. : The current study used a mixed-method design to examine the influence of client- and counselor-level factors on 90-day treatment retention, satisfaction, and progress for justice-involved individuals referred to medication-assisted treatment. : The effects of co-occurring disorders (i.e., psychiatric symptoms, anxiety, depression), social functioning (i.e., social support, self-esteem), substance use severity, and treatment motivation on treatment retention, treatment satisfaction, and treatment progress while controlling for counselor-level variance were assessed through multilevel modeling. : Fewer co-occurring disorders and more social support were related to greater treatment satisfaction and progress. A higher level of treatment motivation was associated with greater treatment progress. Mediation of treatment satisfaction on the relationship between client-level factors and treatment progress also was tested. Depression was negatively associated with treatment satisfaction, which in turn led to lower ratings of treatment progress. Social support was positively correlated with treatment satisfaction, which in turn was positively correlated with treatment progress. The association of client substance use severity with treatment retention differed between counselors, so did the association of co-occurring disorders and treatment motivation with treatment satisfaction. Qualitative analyses that were derived from counselors' perception of factors relating to recovery success underscored the importance of integrated interventions, social support, treatment motivation, and therapeutic alliance, and their associations with treatment outcomes. : The current findings highlight the importance of integrated treatment services, collaborating with community corrections, and teaching clients strategies for dealing with deviant peers as to facilitating recovery.
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http://dx.doi.org/10.1080/10826084.2019.1586949DOI Listing
March 2020

Antiretroviral Adherence Following Prison Release in a Randomized Trial of the imPACT Intervention to Maintain Suppression of HIV Viremia.

AIDS Behav 2019 Sep;23(9):2386-2395

The Institute for Global Health and Infectious Diseases, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.

Many people living with HIV (PLWH) pass through correctional facilities each year, a large proportion of whom do not maintain viral suppression following release. We examined the effects of imPACT, an intervention designed to promote post-release viral suppression, on antiretroviral therapy (ART) adherence. PLWH awaiting release from prisons in two southern states were randomized to imPACT (consisting of motivational interviewing, care linkage coordination, and text message medication reminders) versus standard care (SC). ART adherence, measured by unannounced monthly telephone pill counts, was compared between study arms over 6 months post-release. Of 381 participants eligible for post-release follow-up, 302 (79%) completed ≥ 1 of 6 possible pill counts (median: 4; IQR 1-6). Average adherence over follow-up was 80.3% (95% CI 77.5, 83.1) and 81.0% (78.3, 83.6) of expected doses taken in the imPACT and SC arms, respectively. There was no difference between arms when accounting for missing data using multiple imputation (mean difference = - 0.2 percentage points [- 3.7, 3.3]), controlling for study site and week of follow-up. Of the 936 (40.9%) pill counts that were missed, 212 (22.7%) were due to re-incarceration. Those who missed pill counts for any reason were more likely to be unsuppressed, suggesting that they had lower adherence. However, missingness was balanced between arms. Among PLWH released from prison, ART adherence averaged > 80% in both study arms over 6 months-a level higher than seen with most other chronic diseases. However, missing data may have led to an overestimate of adherence. Factors independent of the intervention influence ART adherence in this population and should be identified to inform future targeted interventions.
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http://dx.doi.org/10.1007/s10461-019-02488-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6822683PMC
September 2019

Crystal structures and electronic properties in 3d transition metal doped SrRuO.

Dalton Trans 2019 Apr 22;48(14):4730-4741. Epub 2019 Mar 22.

School of Chemistry, the University of Sydney, Sydney, NSW 2006, Australia.

The synthesis of polycrystalline samples of B-site doped SrRuMO with x≤ 0.2 by solid state methods is described for a number of dopants (M = Mg, Mn, Fe, Co, Ni, Cu, or Zn) and the structures of these established using Synchrotron X-ray powder diffraction, and for SrRuCuO high resolution neutron diffraction. With the exception of M = Cu, samples with x = 0.2 form an orthorhombic Pbnm type perovskite structure at room temperature and these exhibit a sequence of phase transitions upon heating associated with the gradual reduction in the cooperative tilting of the corner sharing octahedra. SrRuCuO forms a unique monoclinic structure at low temperatures and this transforms to the cubic Pm3[combining macron]m structure via an I4/mcm intermediate upon heating. The magnetic and electronic properties of the samples have been studied. Doping results in a decrease in the Curie temperature and at x = 0.2 all the samples are insulators. This is a consequence of the partial oxidation of the Ru cation that narrows the Ru 4d bands coupled with the suppression of the itinerant nature of the Ru 4d electrons due to the random distribution of the dopant cations. Ru L-edge X-ray absorption spectroscopy of the Cu doped samples reveal a gradual increase in the average Ru oxidation sate upon doping. Electrical resistivity measurements show that doping increases the resistivity of the samples, and the temperature dependence of the resistivities are consistent with Arrhenius-type charge conduction.
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http://dx.doi.org/10.1039/c9dt00432gDOI Listing
April 2019

Drug Use Mediates the Relationship Between Depressive Symptoms and Adherence to ART Among Recently Incarcerated People Living with HIV.

AIDS Behav 2019 Aug;23(8):2037-2047

Department of Psychology, Texas Christian University, Fort Worth, TX, USA.

Depression is a known risk factor for antiretroviral therapy (ART) non-adherence, but little is known about the mechanisms explaining this relationship. Identifying these mechanisms among people living with HIV (PLHIV) after release from prison is particularly important, as individuals during this critical period are at high risk for both depression and poor ART adherence. 347 PLHIV recently released from prison in North Carolina and Texas were included in analyses to assess mediation of the relationship between depressive symptoms at 2 weeks post-release and ART adherence (assessed by unannounced telephone pill counts) at weeks 9-21 post-release by the hypothesized explanatory mechanisms of alcohol use, drug use, adherence self-efficacy, and adherence motivation (measured at weeks 6 and 14 post-release). Indirect effects were estimated using structural equation models with maximum likelihood estimation and bootstrapped confidence intervals. On average, participants achieved 79% ART adherence. The indirect effect of depression on adherence through drug use was statistically significant; greater symptoms of depression were associated with greater drug use, which was in turn associated with lower adherence. Lower adherence self-efficacy was associated with depressive symptoms, but not with adherence. Depression screening and targeted mental health and substance use services for depressed individuals at risk of substance use constitute important steps to promote adherence to ART after prison release.
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http://dx.doi.org/10.1007/s10461-018-2355-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6555693PMC
August 2019

Approaches for creating comparable measures of alcohol use symptoms: Harmonization with eight studies of criminal justice populations.

Drug Alcohol Depend 2019 01 23;194:59-68. Epub 2018 Oct 23.

Yale School of Medicine, United States. Electronic address:

Background: With increasing data archives comprised of studies with similar measurement, optimal methods for data harmonization and measurement scoring are a pressing need. We compare three methods for harmonizing and scoring the AUDIT as administered with minimal variation across 11 samples from eight study sites within the STTR (Seek-Test-Treat-Retain) Research Harmonization Initiative. Descriptive statistics and predictive validity results for cut-scores, sum scores, and Moderated Nonlinear Factor Analysis scores (MNLFA; a psychometric harmonization method) are presented.

Methods: Across the eight study sites, sample sizes ranged from 50 to 2405 and target populations varied based on sampling frame, location, and inclusion/exclusion criteria. The pooled sample included 4667 participants (82% male, 52% Black, 24% White, 13% Hispanic, and 8% Asian/ Pacific Islander; mean age of 38.9 years). Participants completed the AUDIT at baseline in all studies.

Results: After logical harmonization of items, we scored the AUDIT using three methods: published cut-scores, sum scores, and MNLFA. We found greater variation, fewer floor effects, and the ability to directly address missing data in MNLFA scores as compared to cut-scores and sum scores. MNLFA scores showed stronger associations with binge drinking and clearer study differences than did other scores.

Conclusions: MNLFA scores are a promising tool for data harmonization and scoring in pooled data analysis. Model complexity with large multi-study applications, however, may require new statistical advances to fully realize the benefits of this approach.
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http://dx.doi.org/10.1016/j.drugalcdep.2018.10.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6312501PMC
January 2019

: A self-administered android tablet application for helping individuals on probation make better decisions pertaining to health risk behaviors.

Contemp Clin Trials Commun 2018 Jun 31;10:86-93. Epub 2018 Mar 31.

Institute of Behavioral Research, Texas Christian University, TCU Box 298740, Fort Worth, TX 76129, USA.

This paper describes the development and protocol for feasibility and efficacy testing of a risk reduction intervention designed to improve behavioral health outcomes among drug offenders on probation under community supervision or in residential substance abuse treatment centers. is a self-administered tablet-based intervention for teaching better decision-making skills regarding health risk behaviors, especially those involving HIV risks. We are using pre/post, experimental/control group randomized clinical trial (RCT) in both community and residential probation settings with goals to 1) assess the feasibility and acceptance of by examining participation rates and satisfaction measures, and 2) examine the impact of on decision-making skills, confidence and motivation to avoid sex and drug risks, willingness to discuss health risks and concerns with helpful others, and engagement in health risk behaviors. consists of 12 brief sessions and utilizes an evidence-based decision-making schema, called WORKIT, which guides participants through steps for identifying the problem and options, evaluating the options and making a decision about which option to carry out. Multiple sessions of provide a practice effect so that the WORKIT steps become easily accessible to participants when making decisions. Three of the sessions provide participants a choice of activities designed to provide additional information about HIV and reinforce lessons learned during the WORKIT sessions. Preliminary data demonstrate feasibility and high levels of satisfaction with .
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http://dx.doi.org/10.1016/j.conctc.2018.03.010DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6047315PMC
June 2018

The TCU Drug Screen 5: Identifying Justice-involved Individuals with Substance Use Disorders.

J Offender Rehabil 2018 5;57(8):525-537. Epub 2019 Feb 5.

Institute of Behavioral Research, Texas Christian University, Fort Worth, TX.

The TCU Drug Screen II, a widely used instrument for identifying substance use problems, was originally developed based on Diagnostic and Statistical Manual of Mental Disorders III-R criteria. In 2013, the American Psychiatric Association revised the criteria and classification scheme for substance use disorders (SUDs) with the publication of the DSM-5. Subsequently, the TCU Drug Screen was modified to reflect the updated DSM-5. The current study examines the concordance of the TCU Drug Screen II and TCU Drug Screen 5 with adult and juvenile justice-involved samples. Both versions were administered to 305 adult male and 310 juvenile male justice-involved clients as part of standard intake procedures. Results revealed a high level of agreement between the two versions; however, the TCU Drug Screen 5 detected significantly more cases of SUDs, the majority of which corresponded to a mild SUD. Results documented appropriate discrimination in meeting diagnostic thresholds among both age groups, with fewer adolescents identified as having a disorder. Overall, the results suggest that the TCU Drug Screen 5 is comparable to the TCU Drug Screen II with the added potential benefit of DSM-5 conformity and severity specifiers.
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http://dx.doi.org/10.1080/10509674.2018.1549180DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6820856PMC
February 2019

Reply.

J Acquir Immune Defic Syndr 2017 09;76(1):e21-e22

*The Institute of Global Health and Infectious Diseases, The University of North Carolina at Chapel Hill, Chapel Hill, NC †Institute of Behavioral Research, Texas Christian University, Fort Worth, TX.

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http://dx.doi.org/10.1097/QAI.0000000000001457DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5779088PMC
September 2017

Lessons Learned From the Implementation of Seek, Test, Treat, Retain Interventions Using Mobile Phones and Text Messaging to Improve Engagement in HIV Care for Vulnerable Populations in the United States.

AIDS Behav 2017 Nov;21(11):3182-3193

Services Research Branch, National Institute on Drug Abuse, Bethesda, MD, USA.

In the United States, little is known about interventions that rely on mobile phones and/or text messaging to improve engagement in HIV care for vulnerable populations. Domestic studies using these technologies as part of the National Institute on Drug Abuse "Seek, Test, Treat, Retain" research initiative were queried regarding intervention components, implementation issues, participant characteristics, and descriptive statistics of mobile phone service delivery. Across five studies with 1,135 predominantly male, minority participants, implementation challenges occurred in three categories: (1) service interruptions; (2) billing/overage issues, and; (3) the participant user experience. Response rules for automated text messages frequently frustrated participants. The inability to reload minutes/texting capacity remotely was a significant barrier to intervention delivery. No study encountered confidentiality breaches. Service interruption was common, even if studies provided mobile phones and plans. Future studies should attend to the type of mobile phone and service, the participant user experience, and human subjects concerns.
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http://dx.doi.org/10.1007/s10461-017-1804-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5669804PMC
November 2017

The impact of anion ordering on octahedra distortion and phase transitions in SrTaON and BaTaON.

Acta Crystallogr B Struct Sci Cryst Eng Mater 2017 Jun 1;73(Pt 3):389-398. Epub 2017 Jun 1.

Department of Earth Sciences, The Natural History Museum, Cromwell Road, London SW7 5BD, England.

In this work we synthesized BaTaON and SrTaON using a two-step high-temperature solid-state reaction method and analysed the structural distortions, relative to the ideal cubic perovskite structure, according to group theory. From a complete distortion analysis/refinement using high-resolution neutron diffraction data in the temperature range 8 to 613 K, we identified tetragonal structures for BaTaON [P4/mmm (No. 123)] and SrTaON [I4/mcm (No. 140)]. In contrast to an anion-disordered cubic perovskite (Pm \overline{3}m No. 221) with Ta at the cell center, both systems show a site preference for oxygen anions in the two opposite corners (along the c axis) of the Ta-O/N octahedra rather than the four square corners in the ab plane (Γ occupancy distortion), which induces a tetragonal elongation of the unit cell with the c axis being longer than the a axis. A further Ta-O/N octahedra displacement [R(a,0,0), rotation about the c axis] distortion was observed in SrTaON. This distortion mode is accompanied by an increased unit-cell distortion that decreases as the temperature increases. Ultimately a second-order phase transition caused by the loss of the R(a,0,0) mode was observed at 400-450 K.
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http://dx.doi.org/10.1107/S2052520617001123DOI Listing
June 2017

Cohort profile: seek, test, treat and retain United States criminal justice cohort.

Subst Abuse Treat Prev Policy 2017 05 16;12(1):24. Epub 2017 May 16.

School of Medicine, University of Washington, Seattle, WA, USA.

Background: The STTR treatment cascade provides a framework for research aimed at improving the delivery of services, care and outcomes of PLWH. The development of effective approaches to increase HIV diagnoses and engage PLWH in subsequent steps of the treatment cascade could lead to earlier and sustained ART treatment resulting in viral suppression. There is an unmet need for research applying the treatment cascade to improve outcomes for those with criminal justice involvement.

Methods: The Seek, Test, Treat, and Retain (STTR) criminal justice (CJ) cohort combines data from 11 studies across the HIV treatment cascade that focused on persons involved in the criminal justice system, often but not exclusively for reasons related to substance use. The studies were conducted in a variety of CJ settings and collected information across 11 pre-selected domains: demographic characteristics, CJ involvement, HIV risk behaviors, HIV and/or Hepatitis C infections, laboratory measures of CD4 T-cell count (CD4) and HIV RNA viral load (VL), mental illness, health related quality of life (QoL), socioeconomic status, health care access, substance use, and social support.

Results: The STTR CJ cohort includes data on 11,070 individuals with and without HIV infection who range in age from 18 to 77 years, with a median age at baseline of 37 years. The cohort reflects racial, ethnic and gender distributions in the U.S. CJ system, and 64% of participants are African-American, 12% are Hispanic and 83% are men. Cohort members reported a wide range of HIV risk behaviors including history of injection drug use and, among those who reported on pre-incarceration sexual behaviors, the prevalence of unprotected sexual intercourse ranged across studies from 4% to 79%. Across all studies, 53% percent of the STTR CJ cohort reported recent polysubstance use.

Conclusions: The STTR CJ cohort is comprised of participants from a wide range of CJ settings including jail, prison, and community supervision who report considerable diversity in their characteristics and behavioral practices. We have developed harmonized measures, where feasible, to improve the integration of these studies together to answer questions that cannot otherwise be addressed.
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http://dx.doi.org/10.1186/s13011-017-0107-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5433052PMC
May 2017

Daily stressors as antecedents, correlates, and consequences of alcohol and drug use and cravings in community-based offenders.

Psychol Addict Behav 2017 05 6;31(3):315-325. Epub 2017 Apr 6.

Institute of Behavioral Research, Texas Christian University.

Justice-involved individuals with alcohol and drug use problems reoffend at higher rates than their nonusing counterparts, with alcohol and drug use serving as an important vector to recidivism. At the daily level, exposure to stressors may exacerbate problematic alcohol and drug use; at the individual level, prior treatment experiences may mitigate substance use as individuals adapt to and learn new coping mechanisms. We conducted a daily diary study using Interactive Voice Response technology over 14 consecutive days with 117 men on probation or parole participating in a community-based treatment program (n = 860 calls) and referred to medication-assisted treatment. Participants reported daily stressors, craving for alcohol and illegal drugs, and use of alcohol and illegal drugs 1 time each day. Results of multilevel models showed significant day-to-day fluctuation in alcohol and drug craving and use. In concurrent models, increases in daily stressors were associated with increases in cravings and use of illegal drugs. Prior treatment experience modified many of these relationships, and additional lagged models revealed that those with less treatment experience reported an increase in next-day alcohol craving when they experienced increases in stressors on the previous day compared to those with more treatment experience. Collectively, these findings highlight the importance of tailoring treatment as a function of individual differences, including prior treatment experiences, and targeting daily stressors and subsequent cravings among justice-involved adults with alcohol and drug use problems. (PsycINFO Database Record
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http://dx.doi.org/10.1037/adb0000276DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5443110PMC
May 2017

Randomized Controlled Trial of an Intervention to Maintain Suppression of HIV Viremia After Prison Release: The imPACT Trial.

J Acquir Immune Defic Syndr 2017 05;75(1):81-90

*The Institute for Global Health and Infectious Diseases, The University of North Carolina at Chapel Hill, Chapel Hill, NC; †The Institute of Behavioral Research, Texas Christian University, Fort Worth, TX; and ‡Division of Infectious Diseases, The University of Alabama School of Medicine, Birmingham, AL.

Background: HIV-infected individuals transitioning from incarceration to the community are at risk for loss of viral suppression. We compared the effects of imPACT, a multidimensional intervention to promote care engagement after release, to standard care on sustaining viral suppression after community re-entry.

Methods: This trial randomized 405 HIV-infected inmates being released from prisons in Texas and North Carolina with HIV-1 RNA levels <400 copies/mL to imPACT versus standard care. The imPACT arm received motivational interviewing prerelease and postrelease, referral to care within 5 days of release, and a cellphone for medication text reminders. The standard care arm received routine discharge planning and a cellphone for study staff contact. The primary outcome was the difference between arms in week 24 postrelease viral suppression (HIV-1 RNA <50 copies/mL) using intention-to-treat analysis with multiple imputation of missing data.

Results: The proportion with 24-week HIV-1 RNA <50 copies/mL was 60% and 61% in the imPACT and standard care arms, respectively [odds ratio for suppression 0.95 (95% confidence interval: 0.59 to 1.53)]. By week 6 postrelease, 86% in the imPACT arm versus 75% in the standard care arm attended at least 1 nonemergency clinic visit (P = 0.02). At week 24, 62% in both arms reported not missing any antiretroviral doses in the past 30 days (P > 0.99).

Conclusions: Higher rates of HIV suppression and medical care engagement than expected based on previous literature were observed among HIV-infected patients with suppressed viremia released from prison. Randomization to a comprehensive intervention to motivate and facilitate HIV care access after prison release did not prevent loss of viral suppression. A better understanding of the factors influencing prison releasees' linkage to community care, medication adherence, and maintenance of viral suppression is needed to inform policy and other strategic approaches to HIV prevention and treatment.
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http://dx.doi.org/10.1097/QAI.0000000000001337DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5443668PMC
May 2017

Co-calibration of two self-reported measures of adherence to antiretroviral therapy.

AIDS Care 2017 04 2;29(4):464-468. Epub 2016 Dec 2.

a Department of Medicine , University of Washington , Seattle , WA , USA.

Adherence to antiretroviral therapy (ART) is an important determinant of clinical success assessed in many HIV studies. Harmonizing adherence data from studies that use different measures is difficult without a co-calibration equation to convert between validated instruments. Our purpose was to co-calibrate two commonly used adherence measures: the AIDS Clinical Trials Group (ACTG) questionnaire and the Visual Analog Scale (VAS). We used robust linear regression to develop a co-calibration equation in a clinical care cohort. The outcome was the 30-day VAS percentage of ART taken and the predictors were ACTG questions. We evaluated the equation's goodness of fit in five STTR (Seek, Test, Treat, Retain) consortium studies where individuals completed both measures: 2 criminal justice; 2 international; and 1 other high-risk vulnerable population. We developed a three-phase decision rule to convert ACTG to VAS in 1045 participants. First, when the last missed dose on the ACTG was reported as >30 days ago, the VAS was set to 100% (N = 582). Second, if "doses missed" was zero for all items, VAS was 100% (N = 104). Third, among remaining participants (N = 359), VAS was estimated as 96.8% minus 2.9% times the number of missed doses ("doses per day" was non-significant). Correlation between predicted and reported VAS was r = 0.80 in the criminal justice group (N = 446), r = 0.46 in the international group (N = 311), r = 0.32 in the other vulnerable population (N = 63), and r = 0.66 overall. When outliers due to inversion of the VAS scale were excluded (n = 25), these correlations were 0.88, 0.78, 0.80, and 0.86, respectively. We concluded that a simple decision rule and equation allowed us to co-calibrate between two widely used adherence measures thus combining data from studies with different instruments. This study highlighted issues with VAS inversions and its limitations as a single item. Combining studies using different instrument facilitates larger pooled datasets to address key research questions.
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http://dx.doi.org/10.1080/09540121.2016.1263721DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5291764PMC
April 2017

Individuals motivated to participate in adherence, care and treatment (imPACT): development of a multi-component intervention to help HIV-infected recently incarcerated individuals link and adhere to HIV care.

BMC Public Health 2016 09 6;16:935. Epub 2016 Sep 6.

School of Medicine, 321 S The University of North Carolina at Chapel Hill, Chapel Hill, USA.

Background: Policy-makers promote a seek, test, treat and retain (STTR) strategy to expand HIV testing, support linkage and engagement in care, and enhance the continuous use of antiretroviral therapy for those HIV-infected. This HIV prevention strategy is particularly appropriate in correctional settings where HIV screening and treatment are routinely available yet many HIV-infected individuals have difficulty sustaining sufficient linkage and engagement in care, disease management, and viral suppression after prison release.

Methods/design: Our research team developed Project imPACT (individuals motivated to Participate in Adherence, Care and Treatment), a multi-component approach for HIV-Infected recently incarcerated individuals that specifically targets their care linkage, retention, and medication adherence by addressing multiple barriers to care engagement after release. The ultimate goals of this intervention are to improve the health of HIV-infected individuals recently released from prison and reduce HIV transmission to their communities by maintaining viral suppression. This paper describes the intervention and technology development processes, based on best practices for intervention development and process evaluation. These processes included: 1) identifying the target population; 2) clarifying the theoretical basis for intervention design; 3) describing features of its foundational interventions; 4) conducting formative qualitative research; 5) integrating and adapting foundational interventions to create and refine intervention content based on target audience feedback. These stages along with the final intervention product are described in detail. The intervention is currently being evaluation and a two arm randomized, controlled trial in two US state prison systems.

Discussion: Based on a literature review, qualitative research, integration of proven interventions and behavioral theory, the final imPACT intervention focused on the transition period two to three months before and three months after prison release. It emphasized pre-release readiness, pre- and post-release supportive non-judgmental counseling, linking individuals to a HIV care clinic and technological supports through videos and text messages. This article provides a useful model for how researchers can develop, test, and refine multi-component interventions to address HIV care linkage, retention and adherence.

Clinical Trial Registration: NCT01629316 , first registered 6-4-2012; last updated 6-9-2015.
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http://dx.doi.org/10.1186/s12889-016-3511-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5011897PMC
September 2016

CORRELATES OF INTERORGANIZATIONAL SERVICE COORDINATION IN COMMUNITY CORRECTIONS.

Crim Justice Behav 2016 Apr 29;43(4):483-505. Epub 2015 Oct 29.

Providence Veteran Affairs Medical Center, Brown University.

Because weak interagency coordination between community correctional agencies (e.g., probation and parole) and community-based treatment providers has been identified as a major barrier to the use of evidence-based practices (EBPs) for treating druginvolved offenders, this study sought to examine how key organizational (e.g., leadership, support, staffing) and individual (e.g., burnout, satisfaction) factors influence interagency relationships between these agencies. At each of 20 sites, probation/parole officials ( = 366) and community treatment providers ( = 204) were surveyed about characteristics of their agencies, themselves, and interorganizational relationships with each other. Key organizational and individual correlates of interagency relationships were examined using hierarchical linear models (HLM) analyses, supplemented by interview data. The strongest correlates included Adaptability, Efficacy, and Burnout. Implications for policy and practice are discussed.
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http://dx.doi.org/10.1177/0093854815607306DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4988680PMC
April 2016

Medication-Assisted Treatment and Violent Outcomes in Community-Based Offenders with Alcohol and Drug Use Problems.

Psychol Violence 2016 Jul 24;6(3):378-389. Epub 2016 Mar 24.

Institute of Behavioral Research, Texas Christian University.

Objective: This study explored medication-assisted treatment (MAT), the combined use of medication and psychosocial treatment, as a strategy for reducing violent outcomes in community-based offenders. The primary aims were to: 1) examine associations between participant characteristics and treatment adherence; 2) examine associations between treatment adherence and substance use; 3) examine associations between treatment adherence and violent outcomes; and 4) determine whether associations between treatment adherence and violent outcomes may be attributable to reductions in substance use.

Method: Baseline interviews were completed with 129 male offenders in community-based treatment prior to their first MAT appointment. Follow-up interviews ( = 91) were conducted approximately 90 days later.

Results: Participant age was associated with medication adherence. Medication nonadherence was associated with at least occasional alcohol use, but not drug use. Conversely, missing several counseling sessions was associated with at least occasional drug use, but not alcohol use. Results of multivariable analyses suggested MAT may be effective in reducing violent outcomes, and victimization specifically, through reductions in alcohol use.

Conclusion: Findings provide evidence supporting MAT as an intervention for victimization. Continued efforts are needed to explore strategies to promote treatment adherence and reduce violent outcomes in community-based offenders with alcohol and drug use problems.
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http://dx.doi.org/10.1037/vio0000047DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4979558PMC
July 2016

A Brief Assessment for HIV Risk: The TCU HVHP Form.

J Correct Health Care 2016 07;22(3):225-39

Institute of Behavioral Research, Texas Christian University, Fort Worth, TX, USA.

Targeted HIV screens may help identify some risk-related concerns of drug-using offenders. The present study describes the Texas Christian University HIV/Hepatitis Risk Assessment (TCU HVHP) form, a 19-item self-report instrument measuring HIV and hepatitis risks based on a sample (N = 1,056) of offenders in eight prisons. Principal components analysis indicated four scales (Injection Risk, Condom Attitudes, Sex Risk, and AIDS Concern) with reliable psychometric properties with coefficient α reliabilities ranging from .72 to .88. Concurrent validities indicated the four scales were related to motivation for treatment, level of drug use, psychosocial functioning, and criminal thinking, although the patterns varied by gender. The TCU HVHP Form should be attractive to programs needing a brief assessment measuring HIV risk behaviors, attitudes toward condom use, and concerns about acquiring and transmitting HIV.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5080836PMC
http://dx.doi.org/10.1177/1078345816653871DOI Listing
July 2016

NMR identification of the binding surfaces involved in the Salmonella and Shigella Type III secretion tip-translocon protein-protein interactions.

Proteins 2016 08 5;84(8):1097-107. Epub 2016 May 5.

Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas, 66045.

The type III secretion system (T3SS) is essential for the pathogenesis of many bacteria including Salmonella and Shigella, which together are responsible for millions of deaths worldwide each year. The structural component of the T3SS consists of the needle apparatus, which is assembled in part by the protein-protein interaction between the tip and the translocon. The atomic detail of the interaction between the tip and the translocon proteins is currently unknown. Here, we used NMR methods to identify that the N-terminal domain of the Salmonella SipB translocon protein interacts with the SipD tip protein at a surface at the distal region of the tip formed by the mixed α/β domain and a portion of its coiled-coil domain. Likewise, the Shigella IpaB translocon protein and the IpaD tip protein interact with each other using similar surfaces identified for the Salmonella homologs. Furthermore, removal of the extreme N-terminal residues of the translocon protein, previously thought to be important for the interaction, had little change on the binding surface. Finally, mutations at the binding surface of SipD reduced invasion of Salmonella into human intestinal epithelial cells. Together, these results reveal the binding surfaces involved in the tip-translocon protein-protein interaction and advance our understanding of the assembly of the T3SS needle apparatus. Proteins 2016; 84:1097-1107. © 2016 Wiley Periodicals, Inc.
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http://dx.doi.org/10.1002/prot.25055DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5261137PMC
August 2016

X-ray and neutron powder diffraction analyses of Gly·MgSO4·5H2O and Gly·MgSO4·3H2O, and their deuterated counterparts.

Acta Crystallogr C Struct Chem 2016 Mar 23;72(Pt 3):203-16. Epub 2016 Feb 23.

Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, England.

We have identified a new compound in the glycine-MgSO4-water ternary system, namely glycine magnesium sulfate trihydrate (or Gly·MgSO4·3H2O) {systematic name: catena-poly[[tetraaquamagnesium(II)]-μ-glycine-κ(2)O:O'-[diaquabis(sulfato-κO)magnesium(II)]-μ-glycine-κ(2)O:O']; [Mg(SO4)(C2D5NO2)(D2O)3]n}, which can be grown from a supersaturated solution at ∼350 K and which may also be formed by heating the previously known glycine magnesium sulfate pentahydrate (or Gly·MgSO4·5H2O) {systematic name: hexaaquamagnesium(II) tetraaquadiglycinemagnesium(II) disulfate; [Mg(D2O)6][Mg(C2D5NO2)2(D2O)4](SO4)2} above ∼330 K in air. X-ray powder diffraction analysis reveals that the trihydrate phase is monoclinic (space group P21/n), with a unit-cell metric very similar to that of recently identified Gly·CoSO4·3H2O [Tepavitcharova et al. (2012). J. Mol. Struct. 1018, 113-121]. In order to obtain an accurate determination of all structural parameters, including the locations of H atoms, and to better understand the relationship between the pentahydrate and the trihydrate, neutron powder diffraction measurements of both (fully deuterated) phases were carried out at 10 K at the ISIS neutron spallation source, these being complemented with X-ray powder diffraction measurements and Raman spectroscopy. At 10 K, glycine magnesium sulfate pentahydrate, structurally described by the `double' formula [Gly(d5)·MgSO4·5D2O]2, is triclinic (space group P-1, Z = 1), and glycine magnesium sulfate trihydrate, which may be described by the formula Gly(d5)·MgSO4·3D2O, is monoclinic (space group P21/n, Z = 4). In the pentahydrate, there are two symmetry-inequivalent MgO6 octahedra on sites of -1 symmetry and two SO4 tetrahedra with site symmetry 1. The octahedra comprise one [tetraaquadiglcyinemagnesium](2+) ion (centred on Mg1) and one [hexaaquamagnesium](2+) ion (centred on Mg2), and the glycine zwitterion, NH3(+)CH2COO(-), adopts a monodentate coordination to Mg2. In the trihydrate, there are two pairs of symmetry-inequivalent MgO6 octahedra on sites of -1 symmetry and two pairs of SO4 tetrahedra with site symmetry 1; the glycine zwitterion adopts a binuclear-bidentate bridging function between Mg1 and Mg2, whilst the Mg2 octahedra form a corner-sharing arrangement with the sulfate tetrahedra. These bridged polyhedra thus constitute infinite polymeric chains extending along the b axis of the crystal. A range of O-H...O, N-H...O and C-H...O hydrogen bonds, including some three-centred interactions, complete the three-dimensional framework of each crystal.
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http://dx.doi.org/10.1107/S2053229616001200DOI Listing
March 2016