Emergency Department Use in Black Individuals With Diabetes.

Objective: The prevalence of diabetes is higher in Black than in White individuals, and Blacks seek emergency department (ED) care for diabetes more often than Whites. This randomized controlled trial compared the efficacy of a novel intervention called the Diabetes Interprofessional Team to Enhance Adherence to Medical Care (DM I-TEAM) to usual medical care (UMC) to prevent return diabetes-related ED visits and hospitalizations over 12 months in 200 Black individuals with diabetes after an ED visit. The trial also identified baseline variables associated with return ED visits and hospitalizations. Methods: The DM I-TEAM provided diabetes education and behavioral activation services delivered by race-concordant research assistants, telehealth visits with a diabetes care and education specialist and primary care physicians, and clinical pharmacist recommendations. Results: Participants had a mean age of 64.9 years, and 73.0% were women. There was no treatment group difference in return diabetes-related ED visits or hospitalizations over 12 months (DM I-TEAM n = 39 [45.3%] vs. UMC n = 37 [38.5%], χ2 = 0.864, P = 0.353). Baseline variables that were associated with return diabetes-related ED visits or hospitalizations were longer duration of diabetes, higher number of chronic health conditions, higher number of previous ED visits or hospitalizations, greater anticholinergic medication burden, lower satisfaction with primary care physicians, and lower trust in physicians (all P ≤0.05). Conclusion: Among Black individuals with diabetes, the DM I-TEAM interprofessional intervention was no better than UMC at preventing return diabetes-related ED visits or hospitalizations. High medical morbidity, greater anticholinergic medication burden, low satisfaction with primary care physicians, and physician mistrust were associated with diabetes-related ED visits or hospitalizations independent of treatment. Before clinical interventions such as the DM I-TEAM can be effective, reducing system-level barriers to health, improving physician-patient relationships and medication prescribing, and building community health care capacity will be necessary.

"Many people have no idea": a qualitative analysis of healthcare barriers among Yazidi refugees in the Midwestern United States.

BACKGROUND: The COVID-19 pandemic has shed new light on inequities in healthcare access faced by immigrant and refugee communities. To address ongoing disparities, there is an urgent need for ecological approaches to better understand the barriers that hinder and resources that facilitate access to healthcare. This study investigates barriers to healthcare system access faced by Yazidi refugees in the Midwestern United States. METHODS: Informed by the Interpretative Phenomenological Approach, three focus group meetings with a community advisory board were conducted between September 2019 and January 2020. The nine-member focus group included social workers, healthcare providers, and members of the Yazidi community. Meeting recordings were transcribed into English, coded for themes, and validated. RESULTS: We describe themes related to specific barriers to healthcare access; analyze the influence of relational dynamics in the focus group; explore experiential themes related to healthcare access in the Yazidi community, and finally interpret our findings through a social-ecological lens. CONCLUSION: Community agencies, healthcare organizations, policymakers, and other stakeholders must work together to develop strategies to reduce systemic barriers to equitable care. Community representation in priority-setting and decision-making is essential to ensure relevance, acceptability, and utilization of developed strategies.

Examining the Macrosystem Level of Influence on Community Health Worker Effectiveness in the State of Nebraska: A Qualitative Approach.

Community health workers (CHWs) serve as the linkage between community and providers and are stakeholders for bridging services to the public. However, integration of CHWs into health care organizations is often lacking. This study explored macrosystem level barriers faced by CHWs and their ability to do their jobs effectively. Using qualitative interviews from CHWs (n = 28) in Nebraska, we used an abductive approach to derive the following themes: (1) CHWs and client macrosystem barriers, (2) CHW workforce supports, and (3) macrosystem solutions for CHW workforce sustainability. Study results also found various macrosystem barriers affecting CHW workforces including immigration policies, insurance policies, funding sources, supervisor support, and obstacles for health seeking of clients. Moreover, through the lens of CHWs, results revealed the need to provide and advocate for solutions that prioritize the needs of CHWs as they continue to fill a crucial gap in community healthcare systems.

Designing a chemical inhibitor for the AAA protein spastin using active site mutations.

Spastin is a microtubule-severing AAA (ATPases associated with diverse cellular activities) protein needed for cell division and intracellular vesicle transport. Currently, we lack chemical inhibitors to probe spastin function in such dynamic cellular processes. To design a chemical inhibitor of spastin, we tested selected heterocyclic scaffolds against wild-type protein and constructs with engineered mutations in the nucleotide-binding site that do not substantially disrupt ATPase activity. These data, along with computational docking, guided improvements in compound potency and selectivity and led to spastazoline, a pyrazolyl-pyrrolopyrimidine-based cell-permeable probe for spastin. These studies also identified spastazoline-resistance-conferring point mutations in spastin. Spastazoline, along with the matched inhibitor-sensitive and inhibitor-resistant cell lines we generated, were used in parallel experiments to dissect spastin-specific phenotypes in dividing cells. Together, our findings suggest how chemical probes for AAA proteins, along with inhibitor resistance-conferring mutations, can be designed and used to dissect dynamic cellular processes.

"It's Been a Whole New World": Staff Perceptions of Implementing a Person-Centered Communication Intervention During the COVID-19 Pandemic.

The coronavirus disease 2019 (COVID-19) has challenged the way nursing homes deliver person-centered care (PCC). Preferences for Activity and Leisure (PAL) Cards are a tool to communicate residents' important preferences to staff. Monthly interviews (N = 32) were conducted with champions who were conducting a PAL Card quality improvement project in Tennessee nursing homes (N = 11) between March and August 2020. Three major themes emerged: Structural Changes (e.g., halting admissions, adding an isolation unit), Resident Burden (e.g., physical isolation, loneliness), and Provider Burnout (e.g., increased workload, mental exhaustion). Further, providers expressed the benefits to using PAL Cards, specifically in regard to blunting the negative impact of each theme. Results showed the overall negative impact of COVID-19 on nursing home communities. Nursing staff experienced greater burden than other staff, reflecting their prominent role in providing direct care to residents with COVID-19. Staff reported that PAL Cards helped promote PCC. [Journal of Gerontological Nursing, 47(5), 9-13.].

Multiple COVID-19 Outbreaks Linked to a Wedding Reception in Rural Maine - August 7-September 14, 2020.

Large indoor gatherings pose a high risk for transmission of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), and have the potential to be super-spreading events (1,2). Such events are associated with explosive growth, followed by sustained transmission (3). During August 7-September 14, 2020, the Maine Center for Disease Control and Prevention (MeCDC) investigated a COVID-19 outbreak linked to a wedding reception attended by 55 persons in a rural Maine town. In addition to the community outbreak, secondary and tertiary transmission led to outbreaks at a long-term care facility 100 miles away and at a correctional facility approximately 200 miles away. Overall, 177 COVID-19 cases were epidemiologically linked to the event, including seven hospitalizations and seven deaths (four in hospitalized persons). Investigation revealed noncompliance with CDC's recommended mitigation measures. To reduce transmission, persons should avoid large gatherings, practice physical distancing, wear masks, stay home when ill, and self-quarantine after exposure to a person with confirmed SARS-CoV-2 infection. Persons can work with local health officials to increase COVID-19 awareness and determine the best policies for organizing social events to prevent outbreaks in their communities.

Neighborhood Characteristics, Maternal Parenting, and Health and Development of Children from Socioeconomically Disadvantaged Families.

The present study examined the direct and indirect effects of neighborhood conditions on the health and development of children from socioeconomically disadvantaged families. Two waves of data were analyzed from the Fragile Families and Child Wellbeing study and its subsample of 3,656 mothers and their young children at ages 3 and 5. The results show that social cohesion was directly and indirectly associated with children's behavioral problems and health status. Social control was found to have an indirect effect on children's behavioral problems and cognitive development transmitted through maternal parenting quality and parenting stress. There were significant direct effects of neighborhood physical disorder on children's behavioral problems and cognitive development. In terms of effect size, mothers' parenting stress and parenting quality, economic hardship, education level, and health care coverage were also prominent factors in determining the health and development of children. Implications for interventions and future research are discussed.

Disparities in Health Information Access: Results of a County-Wide Survey and Implications for Health Communication.

Health knowledge and behavior can be shaped by the extent to which individuals have access to reliable and understandable health information. Based on data from a population-based telephone survey of 1,503 respondents of ages 18 years and older living in Douglas County, Nebraska, in 2013, this study assesses disparities in health information access and their related covariates. The two most frequently reported sources of health information are the Internet and health professionals, followed by print media, peers, and broadcast media. Relative to non-Hispanic Whites, Blacks are more likely to report health professionals as their primary source of health information (odds ratio [OR] = 2.61, p < .001) and less likely to report peers (OR = 0.39, p < .05). A comparison between Whites and Hispanics suggests that Hispanics are less likely to get their health information through the Internet (OR = 0.51, p < .05) and more likely to get it from broadcast media (OR = 4.27, p < .01). Relative to their counterparts, participants with no health insurance had significantly higher odds of reporting no source of health information (OR = 3.46, p < .05). Having no source of health information was also associated with an annual income below $25,000 (OR = 2.78, p < .05 compared to middle income range) and being born outside of the United States (OR = 5.00, p < .05). Access to health information is lowest among society's most vulnerable population groups. Knowledge of the specific outlets through which people are likely to obtain health information can help health program planners utilize the communication channels that are most relevant to the people they intend to reach.

Resource partitioning along multiple niche axes drives functional diversity in parrotfishes on Caribbean coral reefs.

The recent loss of key consumers to exploitation and habitat degradation has significantly altered community dynamics and ecosystem function across many ecosystems worldwide. Predicting the impacts of consumer losses requires knowing the level of functional diversity that exists within a consumer assemblage. In this study, we document functional diversity among nine species of parrotfishes on Caribbean coral reefs. Parrotfishes are key herbivores that facilitate the maintenance and recovery of coral-dominated reefs by controlling algae and provisioning space for the recruitment of corals. We observed large functional differences among two genera of parrotfishes that were driven by differences in diet. Fishes in the genus Scarus targeted filamentous algal turf assemblages, crustose coralline algae, and endolithic algae and avoided macroalgae, while fishes in the genus Sparisoma preferentially targeted macroalgae. However, species with similar diets were dissimilar in other attributes, including the habitats they frequented, the types of substrate they fed from, and the spatial scale at which they foraged. These differences indicate that species that appear to be functionally redundant when looking at diet alone exhibit high levels of complementarity when we consider multiple functional traits. By identifying key functional differences among parrotfishes, we provide critical information needed to manage parrotfishes to enhance the resilience of coral-dominated reefs and reverse phase shifts on algal-dominated reefs throughout the wider Caribbean. Further, our study provides a framework for predicting the impacts of consumer losses in other species rich ecosystems.

cGMP inhibition of type 3 phosphodiesterase is the major mechanism by which C-type natriuretic peptide activates CFTR in the shark rectal gland.

The in vitro perfused rectal gland of the dogfish shark (Squalus acanthias) and filter-grown monolayers of primary cultures of shark rectal gland (SRG) epithelial cells were used to analyze the signal transduction pathway by which C-type natriuretic peptide (CNP) stimulates chloride secretion. CNP binds to natriuretic receptors in the basolateral membrane, elevates cellular cGMP, and opens cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels in the apical membrane. CNP-provoked chloride secretion was completely inhibitable by the nonspecific protein kinase inhibitor staurosporine and the PKA inhibitor H89 but insensitive to H8, an inhibitor of type I and II isoforms of cGMP-dependent protein kinase (cGKI and cGKII). CNP-induced secretion could not be mimicked by nonhydrolyzable cGMP analogs added alone or in combination with the protein kinase C activator phorbolester, arguing against a role for cGK or for cGMP-induced PKC signaling. We failed to detect a dogfish ortholog of cGKII by molecular cloning and affinity chromatography. However, inhibitors of the cGMP-inhibitable isoform of phosphodiesterase (PDE3) including milrinone, amrinone, and cilostamide but not inhibitors of other PDE isoenzymes mimicked the effect of CNP on chloride secretion in perfused glands and monolayers. CNP raised cGMP and cAMP levels in the SRG epithelial cells. This rise in cAMP as well as the CNP and amrinone-provoked chloride secretion, but not the rise in cGMP, was almost completely blocked by the Gαi-coupled adenylyl cyclase inhibitor somatostatin, arguing against a role for cGMP cross-activation of PKA in CNP action. These data provide molecular, functional, and pharmacological evidence for a CNP/cGMP/PDE3/cAMP/PKA signaling cascade coupled to CFTR in the SRG.

Spastin regulates anaphase chromosome separation distance and microtubule-containing nuclear tunnels.

Nuclear envelope reassembly during the final stages of each mitosis depends on disassembling spindle microtubules without disrupting chromosome separation. This process involves the transient recruitment of the ESCRT-III complex and spastin, a microtubule-severing AAA (ATPases associated with diverse cellular activities) mechanoenzyme, to late-anaphase chromosomes. However, dissecting mechanisms underlying these rapid processes, which can be completed within minutes, has been difficult. Here, we combine fast-acting chemical inhibitors with live-cell imaging and find that spindle microtubules, along with spastin activity, regulate the number and lifetimes of spastin foci at anaphase chromosomes. Unexpectedly, spastin inhibition impedes chromosome separation, but does not alter the anaphase localization dynamics of CHMP4B, an ESCRT-III protein, or increase γ-H2AX foci, a DNA damage marker. We show spastin inhibition increases the frequency of lamin-lined nuclear microtunnels that can include microtubules penetrating the nucleus. Our findings suggest failure to sever spindle microtubules impedes chromosome separation, yet reforming nuclear envelopes can topologically accommodate persistent microtubules ensuring nuclear DNA is not damaged or exposed to cytoplasm.

Physical compatibility of ceftriaxone and cefepime in 0.45% sodium chloride, Ringer's lactate solution, and Plasma-Lyte A.

OBJECTIVES: The compatibility of intravenous fluids with medications is of paramount concern to pharmacists and is an imperative component of ensuring patient safety. Data regarding the physical compatibility of medications with intravenous fluids has not been examined, or published with conflicting results or the concentrations studied were not consistent with current practice. Our objective was to determine the physical compatibility of ceftriaxone and cefepime in 0.45% sodium chloride, Ringer's lactate solution, and Plasma-Lyte A. METHODS: An in vitro analysis of the physical compatibility of ceftriaxone and cefepime at 10 mg/mL, 20 mg/mL, and 40 mg/mL concentrations was conducted in 0.45% sodium chloride, Ringer's lactate solution, and Plasma-Lyte A. Admixtures were evaluated in triplicate at hours 0, 1, 5, 8, and 24. Physical compatibility was assessed by visual inspection, spectrophotometry, and pH analysis. RESULTS: Ceftriaxone 40 mg/mL was found to be physically incompatible in 0.45% sodium chloride and Ringer's lactate solution beyond 5 hours and in Plasma-Lyte A beyond 8 hours. Cefepime was found to be physically incompatible with all fluids and in all concentrations beyond 1 hour. CONCLUSIONS: This work contributes to the body of literature dedicated to the evaluation of intravenous drug and fluid physical compatibility by identifying demonstrable changes in admixtures containing 0.45% sodium chloride, Plasma-Lyte A, and Ringer's lactate solution. Ceftriaxone should not be administered with 0.45% sodium chloride, Ringer's lactated solution, or Plasma-Lyte A at selected concentrations and time points and cefepime is not considered to be physically compatible at 10 mg/mL, 20 mg/mL, or 40 mg/mL in any of the studied fluids beyond 1 hour.

High vs. Low Intensity Behavior Therapy Delivered to Adolescents with ADHD: Potential Adverse Long-Term Effects on Substance Use Outcomes.

Individuals with ADHD are at risk for substance use initiation in adolescence and escalation to problematic use in adulthood. Little is known about the impact of psychosocial ADHD treatment on substance use. Based on existing theory, both therapeutic (i.e., through reducing symptoms and impairments) and iatrogenic effects (i.e., through improved social functioning) of psychosocial treatment for ADHD on adolescent substance use initiation are plausible. A primarily ethnic/racial minority sample (~ 95% Latinx or Black) of rising ninth grade students with ADHD (n = 106) were randomly assigned to receive high intensity (i.e., Summer Treatment Program-Adolescent, parent training, and school consultation) or lower intensity (parent training, organization skills training, and school consultation) intervention the summer before entering high school. Participants were followed four-years post-baseline and substance use was documented. Analyses tested treatment effects on substance use initiation (alcohol and/or marijuana) and mediators of main effects. After controlling for covariates, participants assigned to HI (37.5%) were significantly more likely than LI (18.6%) to initiate substance use by end of high school, indicating an iatrogenic effect of HI treatment. No significant mediators were detected. Post-hoc exploration of moderators suggested that youth with elevated Posttraumatic Stress Disorder (PTSD) symptoms may have experienced a benefit of HI treatment on substance use whereas youth without elevated PTSD symptoms experienced iatrogenic effects. Large, well-powered, samples should examine moderated mediational models to better understand who is most risk for iatrogenic effects of ADHD psychosocial treatment and why. Clinicians delivering psychosocial treatment to adolescents with ADHD should monitor for potential iatrogenic effects.

A computational account of the development and evolution of psychotic symptoms.

The mechanisms of psychotic symptoms like hallucinations and delusions are often investigated in fully-formed illness, well after symptoms emerge. These investigations have yielded key insights, but are not well-positioned to reveal the dynamic forces underlying symptom formation itself. Understanding symptom development over time would allow us to identify steps in the pathophysiological process leading to psychosis, shifting the focus of psychiatric intervention from symptom alleviation to prevention. We propose a model for understanding the emergence of psychotic symptoms within the context of an adaptive, developing neural system. We will make the case for a pathophysiological process that begins with cortical hyperexcitability and bottom-up noise transmission, which engenders inappropriate belief formation via aberrant prediction error signaling. We will argue that this bottom-up noise drives learning about the (im)precision of new incoming sensory information because of diminished signal-to-noise ratio, causing an adaptive relative over-reliance on prior beliefs. This over-reliance on priors predisposes to hallucinations and covaries with hallucination severity. An over-reliance on priors may also lead to increased conviction in the beliefs generated by bottom-up noise and drive movement toward conversion to psychosis. We will identify predictions of our model at each stage, examine evidence to support or refute those predictions, and propose experiments that could falsify or help select between alternative elements of the overall model. Nesting computational abnormalities within longitudinal development allows us to account for hidden dynamics among the mechanisms driving symptom formation and to view established symptomatology as a point of equilibrium among competing biological forces.

A computational account of the development and evolution of psychotic symptoms.

The mechanisms of psychotic symptoms like hallucinations and delusions are often investigated in fully-formed illness, well after symptoms emerge. These investigations have yielded key insights, but are not well-positioned to reveal the dynamic forces underlying symptom formation itself. Understanding symptom development over time would allow us to identify steps in the pathophysiological process leading to psychosis, shifting the focus of psychiatric intervention from symptom alleviation to prevention. We propose a model for understanding the emergence of psychotic symptoms within the context of an adaptive, developing neural system. We will make the case for a pathophysiological process that begins with cortical hyperexcitability and bottom-up noise transmission, which engenders inappropriate belief formation via aberrant prediction error signaling. We will argue that this bottom-up noise drives learning about the (im)precision of new incoming sensory information because of diminished signal-to-noise ratio, causing a compensatory relative over-reliance on prior beliefs. This over-reliance on priors predisposes to hallucinations and covaries with hallucination severity. An over-reliance on priors may also lead to increased conviction in the beliefs generated by bottom-up noise and drive movement toward conversion to psychosis. We will identify predictions of our model at each stage, examine evidence to support or refute those predictions, and propose experiments that could falsify or help select between alternative elements of the overall model. Nesting computational abnormalities within longitudinal development allows us to account for hidden dynamics among the mechanisms driving symptom formation and to view established symptomatology as a point of equilibrium among competing biological forces.

Neural and visual processing of social gaze cueing in typical and ASD adults.

Atypical eye gaze in joint attention is a clinical characteristic of autism spectrum disorder (ASD). Despite this documented symptom, neural processing of joint attention tasks in real-life social interactions is not understood. To address this knowledge gap, functional-near infrared spectroscopy (fNIRS) and eye-tracking data were acquired simultaneously as ASD and typically developed (TD) individuals engaged in a gaze-directed joint attention task with a live human and robot partner. We test the hypothesis that face processing deficits in ASD are greater for interactive faces than for simulated (robot) faces. Consistent with prior findings, neural responses during human gaze cueing modulated by face visual dwell time resulted in increased activity of ventral frontal regions in ASD and dorsal parietal systems in TD participants. Hypoactivity of the right dorsal parietal area during live human gaze cueing was correlated with autism spectrum symptom severity: Brief Observations of Symptoms of Autism (BOSA) scores (r = âˆ'0.86). Contrarily, neural activity in response to robot gaze cueing modulated by visual acquisition factors activated dorsal parietal systems in ASD, and this neural activity was not related to autism symptom severity (r = 0.06). These results are consistent with the hypothesis that altered encoding of incoming facial information to the dorsal parietal cortex is specific to live human faces in ASD. These findings open new directions for understanding joint attention difficulties in ASD by providing a connection between superior parietal lobule activity and live interaction with human faces. Lay Summary: Little is known about why it is so difficult for autistic individuals to make eye contact with other people. We find that in a live face-to-face viewing task with a robot, the brains of autistic participants were similar to typical participants but not when the partner was a live human. Findings suggest that difficulties in real-life social situations for autistic individuals may be specific to difficulties with live social interaction rather than general face gaze.

A clinically utilized intravenous continuous rate infusion of diltiazem does not significantly decrease systolic function in healthy dogs.

OBJECTIVE: To determine if left ventricular systolic function on echocardiography, systemic blood pressure, and electrocardiography change with a clinically accepted intravenous (IV) diltiazem constant rate infusion (CRI) compared to a control. ANIMALS: 10 healthy client-owned adult dogs. PROCEDURES: Prospective, masked, crossover study from May 27, 2021, to August 22, 2021. Dogs were randomized to receive diltiazem (loading dose of 240 µg/kg, IV followed by a CRI of 6 µg/kg/min for 300 minutes) or the same volume of 5% dextrose in water (D5W) administered IV followed by the opposite intervention after a 7-day washout. Blood pressure was monitored during each CRI, and echocardiographic and electrocardiographic studies were performed immediately before the CRI and during the last hour of the CRI. RESULTS: Postdiltiazem systolic time interval (STI) (median, 0.30; range, 0.16 to 0.34) was significantly lower than post-D5W STI (median, 0.32; range, 0.22 to 0.40; P = .046). All other echocardiographic parameters did not differ significantly between each of the groups after receiving diltiazem or D5W. Systemic blood pressure did not change significantly with either diltiazem (P = .450) or D5W (P = .940), and none of the dogs became hypotensive at any point in the study. Expectedly, negative dromotropy was observed with diltiazem. CLINICAL RELEVANCE: A significant decrease in left ventricular systolic function was not appreciated in healthy dogs receiving diltiazem at a clinically accepted intravenous infusion rate at this dosing regimen. Further studies are needed in dogs with cardiac disease.

Interprofessional Intervention to Reduce Emergency Department Visits in Black Individuals with Diabetes.

Black individuals with diabetes have high rates of emergency department (ED) use. This randomized controlled trial compared the efficacy of Diabetes Interprofessional Team to Enhance Adherence to Medical Care (DM I-TEAM) versus Usual Medical Care (UMC) to reduce number of return ED visits/hospitalizations over 12 months in 200 Black individuals with diabetes after an ED visit. DM I-TEAM consisted of community health worker-delivered diabetes education and behavior activation, telehealth visits with a diabetes nurse educator and primary care physicians, and clinical pharmacist recommendations to reduce potentially inappropriate medications (PIMs). Secondary outcomes included glycemic control, PIMs use, diabetes self-management, diabetes self-efficacy, depression, and medical trust. Participants had a mean age of 64.9 years and 73.0% were women. The 2 treatment groups were similar in baseline characteristics. Sixty-eight (69.4%) DM I-TEAM participants and 69 (67.6%) UMC participants had at least 1 incident ED visit/hospitalization over 12 months. The adjusted incidence rate ratio for DM I-TEAM versus UMC was 1.11 (95% confidence interval 0.79-1.56; P = 0.54). DM I-TEAM participants attained significantly better diabetes self-management, diabetes self-efficacy, and institutional trust than UMC participants. There were no treatment group differences in hemoglobin A1c level nor PIMs use. Among Black individuals with diabetes, a novel culturally relevant intervention was no better than usual care at preventing return ED visits/hospitalizations over 1 year. Before reasonable clinical interventions such as DM I-TEAM can be effective, reducing system-level barriers to health, building community health care capacity, and designing interventions that better align with the everyday realities of patients' lives are necessary. clinicaltrials.gov NCT03393338.

High-content microscopy reveals a morphological signature of bortezomib resistance.

Drug resistance is a challenge in anticancer therapy. In many cases, cancers can be resistant to the drug prior to exposure, that is, possess intrinsic drug resistance. However, we lack target-independent methods to anticipate resistance in cancer cell lines or characterize intrinsic drug resistance without a priori knowledge of its cause. We hypothesized that cell morphology could provide an unbiased readout of drug resistance. To test this hypothesis, we used HCT116 cells, a mismatch repair-deficient cancer cell line, to isolate clones that were resistant or sensitive to bortezomib, a well-characterized proteasome inhibitor and anticancer drug to which many cancer cells possess intrinsic resistance. We then expanded these clones and measured high-dimensional single-cell morphology profiles using Cell Painting, a high-content microscopy assay. Our imaging- and computation-based profiling pipeline identified morphological features that differed between resistant and sensitive cells. We used these features to generate a morphological signature of bortezomib resistance. We then employed this morphological signature to analyze a set of HCT116 clones (five resistant and five sensitive) that had not been included in the signature training dataset, and correctly predicted sensitivity to bortezomib in seven cases, in the absence of drug treatment. This signature predicted bortezomib resistance better than resistance to other drugs targeting the ubiquitin-proteasome system, indicating specificity for mechanisms of resistance to bortezomib. Our results establish a proof-of-concept framework for the unbiased analysis of drug resistance using high-content microscopy of cancer cells, in the absence of drug treatment.