Application of particle swarm optimization to understand the mechanism of action of allosteric inhibitors of the enzyme HSD17ß13.

Understanding a drug candidate's mechanism of action is crucial for its further development. However, kinetic schemes are often complex and multi-parametric, especially for proteins in oligomerization equilibria. Here, we demonstrate the use of particle swarm optimization (PSO) as a method to select between different sets of parameters that are too far apart in the parameter space to be found by conventional approaches. PSO is based upon the swarming of birds: each bird in the flock assesses multiple landing spots while at the same time sharing that information with its neighbors. We applied this approach to the kinetics of HSD17ß13 enzyme inhibitors, which displayed unusually large thermal shifts. Thermal shift data for HSD17ß13 indicated that the inhibitor shifted the oligomerization equilibrium toward the dimeric state. Validation of the PSO approach was provided by experimental mass photometry data. These results encourage further exploration of multi-parameter optimization algorithms as tools in drug discovery.

Client Retention in Community Treatment: Completer and Noncompleter Experiences of an Individualized, Needs-Based Partner Abuse Intervention Program.

There has been increased interest in the subjective experiences of participants of community partner abuse intervention programs (PAIPs). In the context of high attrition rates, qualitative research is needed to understand the factors associated with sustained engagement and dropout. Using a community nonmandated PAIP, the current study is a rare investigation of the experiences of both completers and noncompleters. We explored the differences between completers' and noncompleters' perceptions of the treatment process, the reasons for sustained program engagement, and the perceived outcomes of treatment. Semi-structured interviews were completed with 14 participants: nine completers and five noncompleters. The majority of participants were referred by children's social care and were unemployed at the time of interview. The interviews were conducted by research staff independent from the treatment-providing organization. Three themes emerged from the data: (a) Treatment as Challenging Yet Enlightening, (b) the Importance of a Well-timed and Safe Therapeutic Environment, and (c) Improved Emotional Self-Management Due to Treatment. Results highlighted how structured individualized sessions, underpinned by a strong therapeutic alliance with facilitators, helped participants increase their interpersonal problem-solving and communication skills. The study reinforced the importance of developing a therapeutic alliance and providing structured individualized treatment characterized by flexibility and accessibility. Noncompletion was perceived as related to known risk factors and treatment readiness. Therefore, it may be beneficial to employ screening measures to monitor these factors. Future research should use larger, more diverse samples to further investigate subjective experiences of PAIP completers and, particularly, noncompleters to enhance the limited literature in this area.

Potential Utility of Synthetic D-Lactate Polymers in Skin Cancer.

Increased breakdown of glucose through glycolysis in both aerobic and anaerobic conditions is a hallmark feature of mammalian cancer and leads to increased production of L-lactate. The high-level lactate present within the tumor microenvironment is reused as a crucial biofuel to support rapid cancer cell proliferation, survival, and immune evasion. Inhibitors that target the glycolysis process are being developed for cancer therapy. In this study, we report an approach of using synthetic D-lactate dimers to inhibit melanoma and squamous cell carcinoma cell proliferation and survival. We also provide in vivo evidence that intratumoral injection of D-lactate dimers induced an innate immune response and inhibited subcutaneous melanoma xenograft growth in immunodeficient mice. Our findings support a potential utility of D-lactate dimers in skin cancer treatment and therefore warrant further mechanistic studies.

Clinical and Radiographic Predictors of Nonunion in Open Tibial Shaft Fractures.

Open fracture is a risk factor for nonunion of diaphyseal tibia fractures. Compared with closed injuries, there is a relative lack of scientific knowledge regarding the healing of open tibia fractures. The objective of this study was to investigate which patient, injury, and surgeon-related factors predict nonunion in open tibial shaft fractures. A cohort of 98 patients with 104 extra-articular open tibial shaft fractures (OTA/AO 41A2-3, 42A-C, and 43A) were treated surgically between 2007 and 2018 at a single level 1 trauma center and were retrospectively reviewed. Patients underwent irrigation and debridement followed by definitive intramedullary nailing or plate fixation. Patient, injury, and perioperative prognostic factors were analyzed as predictors of nonunion based on anteroposterior and lateral radiographs. The nonunion rate was 27.9% (n=29). There were 12 occurrences of deep infection (11.5%). The median follow-up was 14 months. High-energy mechanism of injury (hazard ratio [HR], 5.76), Gustilo-Anderson class IIIA injury (HR, 3.66), postoperative cortical continuity of 0% to 25% (HR, 2.90), early postoperative complication (HR, 4.20), and deep infection (HR, 2.25) were significant predictors of nonunion on univariable analysis (P<.05). On multivariable assessment, only high-energy mechanism of injury, Gustilo-Anderson class IIIA injury, and early postoperative complication reached significance as predictors of nonunion. These data also indicate that lack of cortical continuity is a significant univariable radiographic predictor of nonunion. This is potentially modifiable, may guide surgeons in selecting patients for early bone grafting procedures, and should be assessed carefully in this high-risk population. [Orthopedics. 2021;44(3):142-147.].

Management of Periprosthetic Hip and Knee Joint Infections With a Known Sinus Tract-A Single-Center Experience.

BACKGROUND: Prosthetic joint infection (PJI) is a serious complication after total joint arthroplasty (TJA). A sinus tract communicating with a prosthetic joint is a major criterion defining PJI. Despite this fact, many patients presenting with a draining sinus tract undergo invasive procedures before initiation of two-stage revision arthroplasty. We hypothesized that many patients undergo nondefinitive procedures to treat the sinus tract, rather than undergoing definitive treatment of infection with two-stage revision. METHODS: A retrospective review of all cases of two-stage revision arthroplasty at Loyola University Medical Center between January 2004 and May 2018 was performed. Patients with infected TJA and periprosthetic sinus tract were included. Records were queried for laboratory values and prior procedures. RESULTS: We identified 160 patients who underwent two-stage revision for infection over the 14-year period. Of the 160 patients, 25 had a documented periprosthetic sinus tract before initiation of definitive revision arthroplasty and were included. Eleven (44.0%) had one or more procedures including interventional radiology drain placement, local wound care, or formal irrigation and debridement before definitive treatment. Forty-five percent of patients that underwent nondefinitive procedures before definitive surgery had either an erythrocyte sedimentation rate or C-reactive protein at normal or near-normal levels. CONCLUSION: Many arthroplasty patients presenting with periprosthetic sinus tracts undergo nondefinitive procedures before definitive treatment. Inherent surgical risks of these procedures can increase the overall morbidity and mortality of these patients. Further effort is needed to educate surgeons regarding management of sinus tracts after TJA.

Quantifying Radiation Exposure From Intraoperative Computed Tomography in Traditionally Safe Operating Room Zones.

OBJECTIVES: To quantify the amount of radiation exposure from a commercially available computed tomography surgical imaging system that occurs in areas of the operating room that are generally believed to be safe and to correlate these amounts with established safety recommendations. DESIGN: Experimental in vitro study. SETTING: Standard hospital operating room at a Level 1 trauma center. PARTICIPANTS: Radiation survey instruments at specified distances from an intraoperative computed tomography scanner. Represented positions were the location of the anesthesiologist (80 cm), the radiation technologist (180 cm), the substerile room (500 cm), the operating room door (600 cm), the next-room nursing station (960 cm), and the hallway (1000 cm). INTERVENTION: Radiation survey instruments were systematically exposed by a protocol intended to imitate expected radiation scatter during operative room use. MAIN OUTCOME MEASUREMENTS: Radiation exposure readings from radiation survey instruments. RESULTS: The mean radiation exposure rates are reported. The mean exposure rate was highest at the anesthesiologist (2200 mrem/h), followed by the door (25.33 mrem/h), the technologist (21.0 mrem/h), the substerile room (8.2 mrem/h), the hallway (2.633 mrem/h), and then the next-room nursing station (1.557 mrem/h). The mean integrated doses per scan were 15.03 mrem for the anesthesiologist, 0.170 mrem for the technologist, 0.136 mrem at the door, 0.033 mrem in the substerile room, 0.014 mrem in the hallway, and 0.005 mrem at the next-door nursing station. The exposure was related both to distance from the machine and to orientation from the machine. CONCLUSIONS: These results indicate that although there is measurable radiation exposure outside of the operating room, the magnitude is low enough to be clinically insignificant. This study provides data that reinforce the need to wear a protective gear or leave the room during the use of intraoperative computed tomography but unsuspecting surrounding staff need not worry about uninformed exposure.

The JNK Signaling Pathway in Inflammatory Skin Disorders and Cancer.

The c-Jun N-terminal kinases (JNKs), with its members JNK1, JNK2, and JNK3, is a subfamily of (MAPK) mitogen-activated protein kinases. JNK signaling regulates a wide range of cellular processes, including cell proliferation, differentiation, survival, apoptosis, and inflammation. Dysregulation of JNK pathway is associated with a wide range of immune disorders and cancer. Our objective is to provide a review of JNK proteins and their upstream regulators and downstream effector molecules in common skin disorders, including psoriasis, dermal fibrosis, scleroderma, basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and melanoma.

Sulfhydryl Labeling as a Tool to Investigate the Topology of Membrane Proteins Involved in Lipopolysaccharide Biosynthesis.

Establishing the topology of membrane proteins, especially when their tridimensional structures are unavailable, is critical to identify functional regions, delimit the protein orientation in the membrane, the number of transmembrane segments, and the position of critical amino acids (whether exposed to the solvent or embedded in the lipid bilayer). Elucidating the topology of bacterial integral membrane proteins typically involves the construction of deletion-fusions whereby regions of the protein are fused to reporters. Although these methods have several advantages, they are also artifact prone. In contrast, methods based on single amino acid substitutions preserve the native protein intact. We describe here an assay to analyze the topology of membrane proteins involved in the biogenesis of bacterial glycoconjugates, which is based on the accessibility of cysteine substitutions at various places in the protein under in vivo and in vitro conditions. Cysteine residues are detected with polyethylene glycol-maleimide (PEG-Mal). This procedure can be applied to crude bacterial cell extracts and does not require protein purification.

Thiol stress-dependent aggregation of the glycolytic enzyme triose phosphate isomerase in yeast and human cells.

The eukaryotic cytosolic proteome is vulnerable to changes in proteostatic and redox balance caused by temperature, pH, oxidants, and xenobiotics. Cysteine-containing proteins are especially at risk, as the thiol side chain is subject to oxidation, adduction, and chelation by thiol-reactive compounds. The thiol-chelating heavy metal cadmium is a highly toxic environmental pollutant demonstrated to induce the heat shock response and recruit protein chaperones to sites of presumed protein aggregation in the budding yeast Saccharomyces cerevisiae. However, endogenous targets of cadmium toxicity responsible for these outcomes are largely unknown. Using fluorescent protein fusion to cytosolic proteins with known redox-active cysteines, we identified the yeast glycolytic enzyme triose phosphate isomerase as being aggregation-prone in response to cadmium and to glucose depletion in chronologically aging cultures. Cadmium-induced aggregation was limited to newly synthesized Tpi1 that was recruited to foci containing the disaggregase Hsp104 and the peroxiredoxin chaperone Tsa1. Misfolding of nascent Tpi1 in response to both cadmium and glucose-depletion stress required both cysteines, implying that thiol status in this protein directly influences folding. We also demonstrate that cadmium proteotoxicity is conserved between yeast and human cells, as HEK293 and HCT116 cell lines exhibit recruitment of the protein chaperone Hsp70 to visible foci. Moreover, human TPI, mutations in which cause a glycolytic deficiency syndrome, also forms aggregates in response to cadmium treatment, suggesting that this conserved enzyme is folding-labile and may be a useful endogenous model for investigating thiol-specific proteotoxicity.

The feasibility and promise of mobile technology with community health worker reinforcement to reduce rural preterm birth.

OBJECTIVES: (1) Assess feasibility of a smartphone platform intervention combined with Community Health Worker (CHW) reinforcement in rural pregnant women; (2) Obtain data on the promise of the intervention on birth outcomes, patient activation, and medical care adherence; and (3) Explore financial implications of the intervention using return on investment (ROI). SAMPLE: A total of 98 rural pregnant women were enrolled and assigned to intervention or control groups in this two-group experimental design. INTERVENTION: The intervention group received usual prenatal care plus a smartphone preloaded with a tailored prenatal platform with automated texting, chat function, and hyperlinks and weekly contact from the CHW. The control group received usual prenatal care and printed educational materials. MEASUREMENTS: Demographics, health risk data, interaction with platform, medical records, hospital billing charges, Client Satisfaction Questionnaire-8, satisfaction comments, and the Patient Activation Measure. RESULTS: A total of 77 women completed the study. The intervention was well-received, showed promise for improving birth outcomes, patient activation, and medical care adherence. Financial analysis showed a positive ROI under two scenarios. CONCLUSIONS: Despite several practical issues, the study appears feasible. The intervention shows promise for extending prenatal care and improving birth outcomes in rural communities. Further research is needed with a larger and more at-risk population to appreciate the impact of the intervention.

A Scoping Review of Transitions, Stress, and Adaptation Among Emerging Adults.

This scoping review examined research on transitions among emerging adults, 18- to 30-year-olds, to identify designs, populations, frameworks, transition types, and transition outcomes. A librarian conducted the search, yielding 2067 articles. Using predefined criteria, teams screened abstracts and reviewed articles, with 82% to 100% interrater agreement. Data from the final 160 articles were placed in evidence tables and summarized. Most frequently, the studies had exploratory-descriptive designs (69%), nondiagnosed samples (58%), no theoretical frameworks (58%), developmental transitions (34%), and health-related behavior outcomes (34%). This transition research is in an early stage of knowledge development and would benefit from further theory development.

Characterization of Outcomes of 2-Stage Exchange Arthroplasty in the Treatment of Prosthetic Joint Infections.

BACKGROUND: Two-stage revision is the preferred treatment for prosthetic hip and knee infections in the United States. Recent studies have questioned the true success rate of this treatment. The purpose of this study is to investigate outcomes of prosthetic hip and knee infections undergoing resection arthroplasty and spacer insertion at a single institution. METHODS: We identified 103 patients who underwent prosthesis resection and spacer placement for infection over a 10-year period. Twenty-three cases were excluded based on preset exclusion criteria leaving 80 cases (56 knees, 24 hips). A retrospective review was performed to examine the outcomes of these patients. RESULTS: Following spacer placement but before reimplantation, 9 (11.25%) of the 80 joints underwent repeat debridement and spacer exchange for persistent infection. Twenty-four (30.00%) patients had a serious complication during their treatment course. Fourteen (17.50%) patients never underwent reimplantation. Of these, 10 continued with spacer retention, 2 had resection arthroplasty, and 1 each had an amputation and an arthrodesis. Of the 66 patients with successful reimplantation, 48 (72.70%) remained infection free at most recent follow-up. CONCLUSIONS: Two-stage revision does not result in the high rates of cure reported previously, when taking into account the substantial number of patients who never undergo the subsequent reimplantation surgery. Of those who underwent reimplantation in our study, many required additional spacer exchange or had complications. Surgeons and patients should consider these outcomes when discussing the treatment of prosthetic hip and knee infections.

Identification of populations at risk: Stillbirth toolkit for health care providers.

BACKGROUND: Maternity care and women's health are measured, in part, by the stillbirth rate of a country. The purposes of this pilot project were to: a) establish a baseline of health care provider knowledge regarding stillbirth risk factors based on geographic distribution (urban/rural) and provider licensure (MD, APRN, PA, CNM) and b) evaluate the utility of a Stillbirth Risk Factor Toolkit and its effects on provider knowledge. METHODS: Evaluative research using a retrospective pre-posttest survey design was completed. The study setting included primary care clinics (urban [n=25] and rural [n=25]) in Nebraska. Health care providers from N=50 clinics were surveyed about their knowledge of stillbirth risk factors (modifiable and non-modifiable) before and after reading the Toolkit. RESULTS: Providers were least knowledgeable regarding the definition of stillbirth and the number of weeks' gestation that constitute a stillbirth. Overall, there was no significant difference in baseline knowledge between rural and urban providers. Nearly half (43.8%) found the Toolkit to be very helpful and applicable to their patient population, and 34.8% said they would be very likely to utilize it with their patients. There was a statistically significant increase in knowledge of stillbirth risk factors among all health care providers after reviewing the Toolkit (p<0.001). CONCLUSIONS: Health providers had varied baseline knowledge about stillbirth. The Toolkit improved provider knowledge, but further research is needed to assess its impact on clinical practice.

Community Advisory Board Members' Perspectives Regarding Opportunities and Challenges of Research Collaboration.

This case study examines the perspectives of rural community advisory board (CAB) members regarding the opportunities and challenges of partnering with academic investigators on funded research. We used a sequential exploratory design to evaluate the phenomena. Qualitative and quantitative data from CAB members were integrated to gain better understanding. Results showed that CAB members valued professional networking and gaining new evidence-based knowledge to enhance their professional practices. They identified rurality, the academic research process, and fulfilling research roles as the most significant challenges. CAB members also believed that strong community-based leaders had been essential in promoting and sustaining a shared vision for evidence-based research solutions to their community problem. Self-evaluation is essential for effective CAB research partnerships, and nurse researchers can strengthen these collaborations by (a) providing continuing education on research and evidence-based practices, (b) assuring that perceived benefits of CAB participation outweigh perceived challenges, and (c) supporting community-based leadership.

Robust Extracellular pH Modulation by Candida albicans during Growth in Carboxylic Acids.

The opportunistic fungal pathogen Candida albicans thrives within diverse niches in the mammalian host. Among the adaptations that underlie this fitness is an ability to utilize a wide array of nutrients, especially sources of carbon that are disfavored by many other fungi; this contributes to its ability to survive interactions with the phagocytes that serve as key barriers against disseminated infections. We have reported that C. albicans generates ammonia as a byproduct of amino acid catabolism to neutralize the acidic phagolysosome and promote hyphal morphogenesis in a manner dependent on the Stp2 transcription factor. Here, we report that this species rapidly neutralizes acidic environments when utilizing carboxylic acids like pyruvate, α-ketoglutarate (αKG), or lactate as the primary carbon source. Unlike in cells growing in amino acid-rich medium, this does not result in ammonia release, does not induce hyphal differentiation, and is genetically distinct. While transcript profiling revealed significant similarities in gene expression in cells grown on either carboxylic or amino acids, genetic screens for mutants that fail to neutralize αKG medium identified a nonoverlapping set of genes, including CWT1, encoding a transcription factor responsive to cell wall and nitrosative stresses. Strains lacking CWT1 exhibit retarded αKG-mediated neutralization in vitro, exist in a more acidic phagolysosome, and are more susceptible to macrophage killing, while double cwt1Δ stp2Δ mutants are more impaired than either single mutant. Together, our observations indicate that C. albicans has evolved multiple ways to modulate the pH of host-relevant environments to promote its fitness as a pathogen. IMPORTANCE: The fungal pathogen Candida albicans is a ubiquitous and usually benign constituent of the human microbial ecosystem. In individuals with weakened immune systems, this organism can cause potentially life-threatening infections and is one of the most common causes of hospital-acquired infections. Understanding the interactions between C. albicans and immune phagocytic cells, such as macrophages and neutrophils, will define the mechanisms of pathogenesis in this species. One such adaptation is an ability to make use of nonstandard nutrients that we predict are plentiful in certain niches within the host, including within these phagocytic cells. We show here that the metabolism of certain organic acids enables C. albicans to neutralize acidic environments, such as those within macrophages. This phenomenon is distinct in several significant ways from previous reports of similar processes, indicating that C. albicans has evolved multiple mechanisms to combat the harmful acidity of phagocytic cells.

An Integrative Review of Postpartum Depression in Rural U.S. Communities.

AIM: This study's aim is to synthesize and summarize the literature on postpartum depression (PPD) in U.S. rural populations. BACKGROUND: Internationally, PPD has a high prevalence in rural communities. Although women in rural U.S. communities have higher rates of depression outside of the postpartum time period, little study has been conducted on PPD in U.S. rural populations. It is unknown whether rural women in the United States have high rates of PPD as is common in rural populations internationally. DESIGN: We used integrative literature review using Whittemore and Knafl's (2005) methodology. DATA SOURCES AND METHODS: We searched the databases MEDLINE, CINAHL, PsycINFO, and Academic Search Premier with the words "postpartum depression" or "postnatal depression" and the word "rural." RESULTS: We found 11 articles with empirical data that met the criteria and thus were included in the review. Seven articles were quantitative, two were qualitative, one was mixed methods, and one was a nonexperimental design. Five foci emerged in the literature including (a) screening and prevalence, (b) demographic factors, (c) program creation and implementation, (d) mental health care seeking, and (e) social support. The results suggest that prevalence of PPD may be higher in rural U.S. areas, that implementing PPD prevention and screening programs for rural women is feasible, and that women in rural areas rely on informal networks and may face a stigma for seeking mental health care. CONCLUSIONS: Further research is needed on PPD in rural U.S. POPULATIONS: Specifically, this research should focus on the mix of variables found throughout this review such as race and income level. Nurses should lead for changes in clinical practice and policy that increase screening and interventions for PPD in rural communities.

Trajectory and Predictors of Depression and Anxiety Disorders in Mothers With the FMR1 Premutation.

BACKGROUND: Although the FMR1 premutation is associated with elevated prevalence of psychiatric disorders, the longitudinal course of symptoms has not been established. The present study followed a sample of women with the FMR1 premutation to characterize the incidence, stability, and predictors of mood and anxiety disorders across a 3-year period. METHODS: Participants included 83 women with the FMR1 premutation (mean age = 38.35) who completed the Structured Clinical Interview for DSM-IV Axis I Disorders at two time points, 3 years apart. Additional information was obtained regarding demographic, child, and biomedical (e.g., medication, menopause, CGG repeats) factors. RESULTS: We found increased prevalence of major depressive disorder (MDD) and anxiety disorders over time, with adverse outcomes predicted by complex interactions among biological, behavioral, and environmental risk factors. Lifetime MDD increased from 46% to 54% and lifetime anxiety disorders increased from 28% to 35%. Midrange CGG repeats, elevated child problem behaviors, and divorced marital status conveyed elevated risk for psychiatric diagnoses. Primary ovarian insufficiency was highly prevalent (41%) but did not account for elevated rates of psychiatric diagnoses. Medication use was highly reported (41%), particularly in women with MDD or anxiety, with selective serotonin reuptake inhibitors reported as the most commonly used medication across diagnostic groups. CONCLUSIONS: The elevated prevalence of depression and anxiety in women with the FMR1 premutation is a clear and pressing concern given the frequent occurrence of the FMR1 premutation in the general community and the adverse outcomes-at both individual and systems levels-associated with psychiatric disorders in this population.

Topological analysis of the Escherichia coli WcaJ protein reveals a new conserved configuration for the polyisoprenyl-phosphate hexose-1-phosphate transferase family.

WcaJ is an Escherichia coli membrane enzyme catalysing the biosynthesis of undecaprenyl-diphosphate-glucose, the first step in the assembly of colanic acid exopolysaccharide. WcaJ belongs to a large family of polyisoprenyl-phosphate hexose-1-phosphate transferases (PHPTs) sharing a similar predicted topology consisting of an N-terminal domain containing four transmembrane helices (TMHs), a large central periplasmic loop, and a C-terminal domain containing the fifth TMH (TMH-V) and a cytosolic tail. However, the topology of PHPTs has not been experimentally validated. Here, we investigated the topology of WcaJ using a combination of LacZ/PhoA reporter fusions and sulfhydryl labelling by PEGylation of novel cysteine residues introduced into a cysteine-less WcaJ. The results showed that the large central loop and the C-terminal tail both reside in the cytoplasm and are separated by TMH-V, which does not fully span the membrane, likely forming a "hairpin" structure. Modelling of TMH-V revealed that a highly conserved proline might contribute to a helix-break-helix structure in all PHPT members. Bioinformatic analyses show that all of these features are conserved in PHPT homologues from Gram-negative and Gram-positive bacteria. Our data demonstrate a novel topological configuration for PHPTs, which is proposed as a signature for all members of this enzyme family.

Accountability for reasonableness: the relevance, or not, of exceptionality in resource allocation.

Accountability for Reasonableness has gained international acceptance as a framework to assist with resource allocation within healthcare. Despite this, one of the four conditions, the relevance condition, has not been widely adopted. In this paper I will start by examining the relevance condition, and the constraints placed on it by Daniels and Sabin. Following this, I review the theoretical limitations of the condition identified to date, by prominent critics such as Rid, Friedman, Lauridsen and Lippert-Rasmussen. Finally, I respond to Daniels and Sabin's enthusiasm for testing the accountability for reasonableness framework in different contexts, by evaluating the challenges of implementing the relevance condition within the NHS. I use the funding of treatments for patients on the basis of their exceptional circumstances as a case study to examine whether the relevance condition could be applied in practice.