The p21+ perinecrotic hepatocytes produce the chemokine CXCL14 after a severe acetaminophen overdose promoting hepatocyte injury and delaying regeneration

Fifty percent of all acute liver failure (ALF) cases in the United States are due to acetaminophen (APAP) overdose. Assessment of canonical features of liver injury, such as plasma alanine aminotransferase activities are poor predictors of acute liver failure (ALF), suggesting the involvement of additional mechanisms independent of hepatocyte death. Previous work demonstrated a severe overdose of APAP results in impaired regeneration, the induction of senescence by p21, and increased mortality. We hypothesized that a discrete population of p21+ hepatocytes acquired a secretory phenotype that directly impedes liver recovery after a severe APAP overdose. Leveraging in-house human APAP explant liver and publicly available single-nuclei RNAseq data, we identified a subpopulation of p21+ hepatocytes enriched in a unique secretome of factors, such as CXCL14. Spatial transcriptomics in the mouse model of APAP overdose confirmed the presence of a p21+ hepatocyte population that directly surrounded the necrotic areas. In both male and female mice, we found a dose-dependent induction of p21 and persistent circulating levels of the p21-specific constituent, CXCL14, in the plasma after a severe APAP overdose. In parallel experiments, we targeted either the putative senescent hepatocytes with the senolytic drugs, dasatinib and quercetin, or CXCL14 with a neutralizing antibody. We found that targeting CXCL14 greatly enhanced liver recovery after APAP-induced liver injury, while targeting senescent hepatocytes had no effect. These data support the conclusion that the sustained induction of p21 in hepatocytes with persistent CXCL14 secretion are critical mechanistic events leading to ALF in mice and human patients.

CT imaging features of bile duct stent complications

Biliary stents have been widely used to treat both malignant and benign biliary obstruction. Biliary stenting serves as a temporary measure to maintain ductal patency and promote bile drainage. Biliary decompression can help relieve clinical symptoms of pain, obstructive jaundice, pruritis, fat malabsorption, and failure to thrive and prevent disease progression, such as secondary biliary cirrhosis and end-stage liver failure. Endoscopic placement of biliary endoprosthesis is a minimally invasive procedure well tolerated by most patients but is not without problems. Multiple early and late complications have been reported in the literature and Computed Tomography (CT) is the most used modality to assess normal positions and evaluate patients suspected of stent complications. The aim of this article is to provide a review various of biliary stent related complications, as seen on CT. Current literature on risk factors, diagnosis and management is also discussed.

2-year survival estimation for decompensated cirrhosis patients of prognostic scoring systems

OBJECTIVE

Prognostic models proposed for cirrhotic patients' survival have not been satisfactorily investigated in the Vietnam population, especially in the medium-term period.

PATIENTS AND METHODS

In this prospective study, we enrolled a total of 904 patients admitted to Hepato-Gastroenterology Center, Bach Mai Hospital from December 2019 to November 2021 and calculated their CP, MELD, MELD-Na score, IMELD, Refit MELD, and Refit MELD-Na after 2-year follow-up to compare their survival prognosis.

RESULTS

The mean age of the patients was 53.8 ±10.8 years, and males constituted 91%. Compared with the surviving group, deceased patients had statistically significant lower albumin, higher INR, serum bilirubin, and creatinine levels with higher means of all prognostic scores. RefitMELD score had the highest AUC (0.768), followed by MELD (0.766), and the lowest belonged to RefitMELDNa (0.669).

CONCLUSIONS

In conclusion, deceased patients had significantly higher values of Child-Pugh score and all MELD-based scores than survival. RefitMELD is the most reliable scoring system to predict 2-year mortality in patients with decompensated liver cirrhosis.

The chemokine CXCL14 is a novel early prognostic biomarker for poor outcome in acetaminophen-induced acute liver failure

BACKGROUND AND AIMS

Patients with acetaminophen-induced acute liver failure are more likely to die while on the liver transplant waiting list than those with other causes of acute liver failure. Therefore, there is an urgent need for prognostic biomarkers that can predict the need for liver transplantation early after an acetaminophen overdose.

APPROACH AND RESULTS

We evaluated the prognostic potential of plasma chemokine C-X-C motif ligand 14 (CXCL14) concentrations in patients with acetaminophen (APAP) overdose (n=50) and found that CXCL14 is significantly higher in nonsurviving patients compared to survivors with acute liver failure ( p < 0.001). Logistic regression and AUROC analyses revealed that CXCL14 outperformed the MELD score, better discriminating between nonsurvivors and survivors. We validated these data in a separate cohort of samples obtained from the Acute Liver Failure Study Group (n = 80), where MELD and CXCL14 had similar AUC (0.778), but CXCL14 demonstrated higher specificity (81.2 vs. 52.6) and positive predictive value (82.4 vs. 65.4) for death or need for liver transplantation. Next, combining the patient cohorts and using a machine learning training/testing scheme to mimic the clinical scenario, we found that CXCL14 outperformed MELD based on AUC (0.821 vs. 0.787); however, combining MELD and CXCL14 yielded the best AUC (0.860).

CONCLUSIONS

We find in 2 independent cohorts of acetaminophen overdose patients that circulating CXCL14 concentration is a novel early prognostic biomarker for poor outcomes, which may aid in guiding decisions regarding patient management. Moreover, our findings reveal that CXCL14 performs best when measured soon after patient presentation to the clinic, highlighting its importance for early warning of poor prognosis.

Dose-dependent pleiotropic role of neutrophils during acetaminophen-induced liver injury in male and female mice

Acetaminophen (APAP) overdose is the leading cause of acute liver failure in western countries. APAP can cause extensive hepatocellular necrosis, which triggers an inflammatory response involving neutrophil and monocyte recruitment. Particularly the role of neutrophils in the injury mechanism of APAP hepatotoxicity has been highly controversial. Thus, the objective of the current study was to assess whether a potential contribution of neutrophils was dependent on the APAP dose and the sex of the animals. Male and female C57BL/6 J mice were treated with 300 or 600 mg/kg APAP and the injury and inflammatory cell recruitment was evaluated between 6 and 48 h. In both male and female mice, ALT plasma levels and the areas of necrosis peaked at 12-24 h after both doses with more severe injury at the higher dose. In addition, Ly6g-positive neutrophils started to accumulate in the liver at 6 h and peaked at 6-12 h after 300 mg/kg and 12-24 h after 600 mg/kg for both sexes; however, the absolute numbers of hepatic neutrophils in the liver were significantly higher after the 600 mg/kg dose. Neutrophil infiltration correlated with mRNA levels of the neutrophil chemoattractant Cxcl2 in the liver. Treating mice with an anti-Cxcl2 antibody at 2 h after APAP significantly reduced neutrophil accumulation at 24 h after both doses and in both sexes. However, the injury was significantly reduced only after the high overdose. Thus, neutrophils, recruited through Cxcl2, have no effect on APAP-induced liver injury after 300 mg/kg but aggravate the injury only after severe overdoses.

The effect of medication event reminder monitoring on treatment adherence of TB patients

BACKGROUND: TB control remains a serious public health problem, compounded by poor treatment adherence, which increases the likelihood of onward transmission. We evaluated the effectiveness of medication event reminder monitoring (MERM) upon treatment adherence in a high TB burden setting.METHODS: We conducted an open-label parallel group randomised controlled trial among pulmonary TB adults. Participants were provided with a MERM device to store their medications. In the intervention arm, the devices were set to provide daily medication intake reminders. Primary outcome was the proportion of patient-months in which at least 6/30 doses were missed. Secondary outcomes included 1) the proportion of patient-months in which at least 14/30 doses were missed, and 2) the proportion of doses missed.RESULTS: Of 2,142 patients screened, 798 (37.3%) met the inclusion criteria and 250 participants were enrolled. The mean ratio (MR) for poor adherence between the intervention and control groups was 0.72 (95% CI 0.55-0.86). The intervention was also associated with a reduction in the proportion of patients missing at least 14/30 doses (MR 0.61, 95% CI 0.54-0.68) and the percentage of total doses missed (MR 0.75, 95% CI 0.68-0.80).CONCLUSION: MERM is effective in improving TB treatment adherence in a resource-limited environment.

Human Wharton's Jelly-derived mesenchymal stem cells prevent acetaminophen-induced liver injury in a mouse model unlike human dermal fibroblasts

The persistence of hepatotoxicity induced by N-acetyl-para-aminophenol (Acetaminophen or Paracetamol, abbreviated as APAP) as the most common cause of acute liver failure in the United States, despite the availability of N-acetylcysteine, illustrates the clinical relevance of additional therapeutic approaches. While human mesenchymal stem cells (MSCs) have shown protection in mouse models of liver injury, the MSCs used are generally not cleared for human use and it is unclear whether these effects are due to xenotransplantation. Here we evaluated GMP manufactured clinical grade human Wharton's Jelly mesenchymal stem cells (WJMSCs), which are currently being investigated in human clinical trials, in a mouse model of APAP hepatotoxicity in comparison to human dermal fibroblasts (HDFs) to address these issues. C57BL6J mice were treated with a moderate APAP overdose (300 mg/kg) and WJMSCs were administered 90 min later. Liver injury was evaluated at 6 and 24 h after APAP. WJMSCs treatment reduced APAP-induced liver injury at both time points unlike HDFs, which showed no protection. APAP-induced JNK activation as well as AIF and Smac release from mitochondria were prevented by WJMSCs treatment without influencing APAP bioactivation. Mechanistically, WJMSCs treatment upregulated expression of Gclc and Gclm to enhance recovery of liver GSH levels to attenuate mitochondrial dysfunction and accelerated recovery of pericentral hepatocytes to re-establish liver zonation and promote liver homeostasis. Notably, preventing GSH resynthesis with buthionine sulfoximine prevented the protective effects of WJMSCs. These data indicate that these GMP-manufactured WJMCs could be a clinically relevant therapeutic approach in the management of APAP hepatotoxicity in humans.

Generation of pro-and anti-inflammatory mediators after acetaminophen overdose in surviving and non-surviving patients

Acetaminophen (APAP) overdose causes liver injury in animals and humans. Although well-studied in animals, limited longitudinal data exist on cytokine release after APAP overdose in patients. The purpose of this study was to quantify concentrations of cytokines in APAP overdose patients to determine if early cytokine or complement measurements can distinguish between surviving and non-surviving patients. Plasma was obtained from healthy controls, APAP overdose patients with no increase in liver transaminases, and surviving and non-surviving APAP overdose patients with severe liver injury. Interleukin-10 (IL-10), and CC chemokine ligand-2 (CCL2, MCP-1) were substantially elevated in surviving and non-surviving patients, whereas IL-6 and CXC chemokine ligand-8 (CXCL8, IL-8) had early elevations in a subset of patients only with liver injury. Day 1 IL-10 and IL-6 levels, and Day 2 CCL2, levels correlated positively with survival. There was no significant increase in IL-1α, IL-1β or TNF-α in any patient during the first week after APAP. Monitoring cytokines such as CCL2 may be a good indicator of patient prognosis; furthermore, these data indicate the inflammatory response after APAP overdose in patients is not mediated by a second phase of inflammation driven by the inflammasome.

Platanosides, a Potential Botanical Drug Combination, Decrease Liver Injury Caused by Acetaminophen Overdose in Mice

Oxidative stress plays an important role in acetaminophen (APAP)-induced hepatotoxicity. Platanosides (PTSs) isolated from the American sycamore tree (Platanus occidentalis) represent a potential new four-molecule botanical drug class of antibiotics active against drug-resistant infectious disease. Preliminary studies have suggested that PTSs are safe and well tolerated and have antioxidant properties. The potential utility of PTSs in decreasing APAP hepatotoxicity in mice in addition to an assessment of their potential with APAP for the control of infectious diseases along with pain and pyrexia associated with a bacterial infection was investigated. On PTS treatment in mice, serum alanine aminotransferase (ALT) release, hepatic centrilobular necrosis, and 4-hydroxynonenal (4-HNE) were markedly decreased. In addition, inducible nitric oxide synthase (iNOS) expression and c-Jun-N-terminal kinase (JNK) activation decreased when mice overdosed with APAP were treated with PTSs. Computational studies suggested that PTSs may act as JNK-1/2 and Keap1-Nrf2 inhibitors and that the isomeric mixture could provide greater efficacy than the individual molecules. Overall, PTSs represent promising botanical drugs for hepatoprotection and drug-resistant bacterial infections and are effective in protecting against APAP-related hepatotoxicity, which decreases liver necrosis and inflammation, iNOS expression, and oxidative and nitrative stresses, possibly by preventing persistent JNK activation.

Iron Availability within the Leaf Vasculature Determines the Magnitude of Iron Deficiency Responses in Source and Sink Tissues in Arabidopsis

Iron (Fe) uptake and translocation in plants are fine-tuned by complex mechanisms that are not yet fully understood. In Arabidopsis thaliana, local regulation of Fe homeostasis at the root level has been extensively studied and is better understood than the systemic shoot-to-root regulation. While the root system is solely a sink tissue that depends on photosynthates translocated from source tissues, the shoot system is a more complex tissue, where sink and source tissues occur synchronously. In this study, and to gain better insight into the Fe deficiency responses in leaves, we overexpressed Zinc/Iron-regulated transporter-like Protein (ZIP5), an Fe/Zn transporter, in phloem-loading cells (proSUC2::AtZIP5) and determined the timing of Fe deficiency responses in sink (young leaves and roots) and source tissues (leaves). Transgenic lines overexpressing ZIP5 in companion cells displayed increased sensitivity to Fe deficiency in root growth assays. Moreover, young leaves and roots (sink tissues) displayed either delayed or dampened transcriptional responses to Fe deficiency compared to wild-type (WT) plants. We also took advantage of the Arabidopsis mutant nas4x-1 to explore Fe transcriptional responses in the opposite scenario, where Fe is retained in the vasculature but in an unavailable and precipitated form. In contrast to proSUC2::AtZIP5 plants, nas4x-1 young leaves and roots displayed a robust and constitutive Fe deficiency response, while mature leaves showed a delayed and dampened Fe deficiency response compared to WT plants. Altogether, our data provide evidence suggesting that Fe sensing within leaves can also occur locally in a leaf-specific manner.

Recovered Hepatocytes Promote Macrophage Apoptosis through CXCR4 after Acetaminophen-Induced Liver Injury in Mice

Acetaminophen (APAP) overdose is the main cause of acute liver failure in Western countries. The mechanism of APAP hepatotoxicity is associated with centrilobular necrosis which initiates infiltration of neutrophils, monocytes, and other leukocytes to the area of necrosis. While it has been recognized that this infiltration of immune cells plays a critical role in promoting liver repair, mechanism of immune cell clearance that is important for resolution of inflammation and the return to normal homeostasis are not well characterized. CXCR4 is a chemokine receptor expressed on hepatocytes as well as neutrophils, monocytes, and hematopoietic stem cells. CXCR4 function is dependent on its selective expression on different cell types and thus can vary depending on the pathophysiology. This study aimed to investigate the crosstalk between hepatocytes and macrophages through CXCR4 to promote macrophage apoptosis after APAP overdose. C57BL/6J mice were subjected to APAP overdose (300 mg/kg). Flow cytometry and immunohistochemistry were used to determine the mode of cell death of macrophages and expression pattern of CXCR4 during the resolution phase of APAP hepatotoxicity. The impact of CXCR4 in regulation of macrophage apoptosis and liver recovery was assessed after administration of a monoclonal antibody against CXCR4. RNAseq analysis was performed on flow cytometry sorted CXCR4+ macrophages at 72 h to confirm the apoptotic cell death of macrophages. Our data indicate that the inflammatory response is resolved by recovering hepatocytes through induction of CXCR4 on macrophages, which triggers their cell death by apoptosis at the end of the recovery phase.

Save the Mekong Delta from drowning

Policy must address drivers, not just symptoms, of subsidence.

Root-to-shoot iron partitioning in Arabidopsis requires IRON-REGULATED TRANSPORTER1 (IRT1) protein but not its iron(II) transport function

IRON-REGULATED TRANSPORTER1 (IRT1) is the root high-affinity ferrous iron (Fe) uptake system and indispensable for the completion of the life cycle of Arabidopsis thaliana without vigorous Fe supplementation. Here we provide evidence supporting a second role of IRT1 in root-to-shoot partitioning of Fe. We show that irt1 mutants overaccumulate Fe in roots, most prominently in the cortex of the differentiation zone in irt1-2, compared to the wild type. Shoots of irt1-2 are severely Fe-deficient according to Fe content and marker transcripts, as expected. We generated irt1-2 lines producing IRT1 mutant variants carrying single amino-acid substitutions of key residues in transmembrane helices IV and V, Ser206 and His232, which are required for transport activity in yeast. Root short-term ⁵⁵ Fe uptake rates were uninformative concerning IRT1-mediated transport. Overall irt1-like concentrations of the secondary substrate Mn suggested that the transgenic Arabidopsis lines also remain incapable of IRT1-mediated root Fe uptake. Yet, IRT1_S206A partially complements rosette dwarfing and leaf chlorosis of irt1-2, as well as root-to-shoot Fe partitioning and gene expression defects of irt1-2, all of which are fully complemented by wild-type IRT1. Taken together, these results suggest a regulatory function for IRT1 in root-to-shoot Fe partitioning that does not require Fe transport activity of IRT1. Among the genes of which transcript levels are partially dependent on IRT1, we identify MYB DOMAIN PROTEIN10, MYB DOMAIN PROTEIN72 and NICOTIANAMINE SYNTHASE4 as candidates for effecting IRT1-dependent Fe mobilization in roots. Understanding the biological functions of IRT1 will help to improve Fe nutrition and the nutritional quality of agricultural crops.

Root-to-shoot iron partitioning in Arabidopsis requires IRON-REGULATED TRANSPORTER1 (IRT1) protein but not its iron(II) transport function

IRON-REGULATED TRANSPORTER1 (IRT1) is the root high-affinity ferrous iron (Fe) uptake system and indispensable for the completion of the life cycle of Arabidopsis thaliana without vigorous Fe supplementation. Here we provide evidence supporting a second role of IRT1 in root-to-shoot partitioning of Fe. We show that irt1 mutants overaccumulate Fe in roots, most prominently in the cortex of the differentiation zone in irt1-2, compared to the wild type. Shoots of irt1-2 are severely Fe-deficient according to Fe content and marker transcripts, as expected. We generated irt1-2 lines producing IRT1 mutant variants carrying single amino-acid substitutions of key residues in transmembrane helices IV and V, Ser206 and His232, which are required for transport activity in yeast. Root short-term ⁵⁵ Fe uptake rates were uninformative concerning IRT1-mediated transport. Overall irt1-like concentrations of the secondary substrate Mn suggested that the transgenic Arabidopsis lines also remain incapable of IRT1-mediated root Fe uptake. Yet, IRT1_S206A partially complements rosette dwarfing and leaf chlorosis of irt1-2, as well as root-to-shoot Fe partitioning and gene expression defects of irt1-2, all of which are fully complemented by wild-type IRT1. Taken together, these results suggest a regulatory function for IRT1 in root-to-shoot Fe partitioning that does not require Fe transport activity of IRT1. Among the genes of which transcript levels are partially dependent on IRT1, we identify MYB DOMAIN PROTEIN10, MYB DOMAIN PROTEIN72 and NICOTIANAMINE SYNTHASE4 as candidates for effecting IRT1-dependent Fe mobilization in roots. Understanding the biological functions of IRT1 will help to improve Fe nutrition and the nutritional quality of agricultural crops.

Kupffer cells regulate liver recovery through induction of chemokine receptor CXCR2 on hepatocytes after acetaminophen overdose in mice

Acetaminophen (APAP) is a widely used analgesic, but also a main cause of acute liver injury in the United States and many western countries. APAP hepatotoxicity is associated with a sterile inflammatory response as shown by the infiltration of neutrophils and monocytes. While the contribution of the immune cells to promote liver repair have been demonstrated, the direct interactions between macrophages or neutrophils with hepatocytes to help facilitate hepatocyte proliferation and tissue repair remain unclear. The purpose of this study was to investigate the relationship between resident macrophages (Kupffer cells) and hepatocytes with a focus on the chemokine receptor CXCR2. C57BL/6J mice were subjected to an APAP overdose (300 mg/kg) and the role of CXCR2 on hepatocytes was investigated using a selective antagonist, SB225002. In addition, clodronate liposomes were used to deplete Kupffer cells to assess changes in CXCR2 expression. Our data showed that CXCR2 was mainly expressed on hepatocytes and it was induced specifically in hepatocytes around the necrotic area 24 h after APAP treatment. Targeting this receptor using an inhibitor caused a delayed liver recovery. Depletion of Kupffer cells significantly prevented CXCR2 induction on hepatocytes. In vitro and in vivo experiments also demonstrated that Kupffer cells regulate CXCR2 expression and pro-regenerative gene expression in surviving hepatocytes through production of IL-10. Thus, Kupffer cells support the transition of hepatocytes around the area of necrosis to a proliferative state through CXCR2 expression.

Recommendations for the use of the acetaminophen hepatotoxicity model for mechanistic studies and how to avoid common pitfalls

Acetaminophen (APAP) is a widely used analgesic and antipyretic drug, which is safe at therapeutic doses but can cause severe liver injury and even liver failure after overdoses. The mouse model of APAP hepatotoxicity recapitulates closely the human pathophysiology. As a result, this clinically relevant model is frequently used to study mechanisms of drug-induced liver injury and even more so to test potential therapeutic interventions. However, the complexity of the model requires a thorough understanding of the pathophysiology to obtain valid results and mechanistic information that is translatable to the clinic. However, many studies using this model are flawed, which jeopardizes the scientific and clinical relevance. The purpose of this review is to provide a framework of the model where mechanistically sound and clinically relevant data can be obtained. The discussion provides insight into the injury mechanisms and how to study it including the critical roles of drug metabolism, mitochondrial dysfunction, necrotic cell death, autophagy and the sterile inflammatory response. In addition, the most frequently made mistakes when using this model are discussed. Thus, considering these recommendations when studying APAP hepatotoxicity will facilitate the discovery of more clinically relevant interventions.

Effectiveness of a multicomponent strategy for implementing guidelines for treating tobacco use in Vietnam Commune Health Centers

INTRODUCTION

Strategies are needed to increase implementation of evidence-based tobacco dependence treatment (TDT) in health care systems in low-and middle-income countries (LMICs).

METHODS

We conducted a two-arm cluster randomized controlled trial to compare the effectiveness of two strategies for implementing TDT guidelines in community health centers (n=26) in Vietnam. Arm 1 included training and a tool kit (e.g., reminder system) to promote and support delivery of the 4As (Ask about tobacco use, Advise to quit, Assess readiness, Assist with brief counseling) (Arm 1). Arm 2 included Arm 1 components plus a system to refer smokers to a community health worker (CHW) for more intensive counseling (4As+R). Provider surveys were conducted at baseline, six- and 12-months to assess the hypothesized effect of the strategies on provider and organizational-level factors. The primary outcome was provider adoption of the 4As.

RESULTS

Adoption of the 4As increased significantly across both study arms (all p<.001). Perceived organizational priority for TDT, compatibility with current workflow, and provider attitudes, norms and self-efficacy related to TDT also improved significantly across both arms. In Arm 2 sites, 41% of smokers were referred to a CHW for additional counseling.

CONCLUSION

The study demonstrated the effectiveness of a multicomponent and multilevel strategy (i.e., provider and system) for implementing evidence-based TDT in the Vietnam public health system. Combining provider-delivered brief counseling with opportunities for more in-depth counseling offered by a trained CHW may optimize outcomes and offers a potentially scalable model for increasing access to TDT in health care systems like Vietnam.

IMPLICATIONS

Improving implementation of evidence-based tobacco dependence treatment (TDT) guidelines is a necessary step towards reducing the growing burden of non-communicable disease (NCDs) and premature death in LMICs. The findings provide new evidence on the effectiveness of multilevel strategies for adapting and implementing TDT into routine care in Vietnam, and offers a potentially scalable model for meeting FCTC Article 14 goals in other LMICs with comparable public health systems. The study also demonstrates that combining provider-delivered brief counseling with referral to a community health worker for more in-depth counseling and support can optimize access to evidence-based treatment for tobacco use.

Feasibility and acceptability of a faith-based mind-body intervention among African American adults

Physical activity reduces cancer risk, yet African American adults remain insufficiently active, contributing to cancer health disparities. Harmony & Health (HH) was developed as a culturally adapted mind-body intervention to promote physical activity, psychosocial well-being, and quality of life among a church-based sample of overweight/obese, insufficiently active African American adults. Men and women were recruited to the study through an existing church partnership. Eligible participants (N = 50) were randomized to a movement-based mind-body intervention (n = 26) or waitlist control (n = 24). Participants in the intervention attended 16 mind-body sessions over 8 weeks and completed a physical assessment, questionnaires on moderate-to-vigorous physical activity (MVPA) and psychosocial factors, and accelerometry at baseline (T1), post-intervention (T2), and 6 week follow-up (T3). Eighty percent of participants (94% women, M age = 49.7 ± 9.4 years, M body mass index = 32.8 ± 5.2 kg/m2) completed the study, and 61.5% of intervention participants attended ≥10 mind-body sessions. Participants self-reported doing 78.8 ± 102.9 (median = 40.7, range: 0-470.7) min/day of MVPA and did 27.1 ± 20.7 (median = 22.0, range: 0-100.5) min/day of accelerometer-measured MVPA at baseline. Trends suggest that mind-body participants self-reported greater improvements in physical activity and psychosocial well-being from baseline to post-intervention than waitlist control participants. HH is feasible and acceptable among African American adults. Trends suggest that the mind-body intervention led to improvements in physical activity and psychosocial outcomes. This study extends the literature on the use of mind-body practices to promote physical and psychological health and reduce cancer disparities in African American adults.

Mitochondrial Membrane Potential Drives Early Change in Mitochondrial Morphology After Acetaminophen Exposure

Mitochondrial morphology plays a critical role in regulating mitochondrial and cellular function. It is well established that oxidative stress and mitochondrial injury are central to acetaminophen (APAP) hepatotoxicity. However, the role of mitochondrial dynamics, namely the remodeling of mitochondrial morphology through fusion and fission, has largely gone unexplored. To investigate this, we used primary mouse hepatocytes treated with APAP which allowed for real-time visualization of mitochondrial morphology using mitotracker green. We found that alterations in mitochondrial morphology were dose dependent, with a biphasic response in mitochondrial shape at higher APAP doses. Importantly, these two distinct mitochondrial morphologies corresponded with differences in mitochondrial respiratory function and polarization. The early change in mitochondrial morphology can be reversible and appears to be an adaptive response caused by alterations in membrane potential, which ultimately help preserve mitochondrial function. The later delayed change in mitochondrial morphology is irreversible and is driven by loss of mitochondrial membrane potential, decreased canonical fusion proteins, and alterations in mitochondrial lipid composition. Collectively, these later changes tilt the scales toward mitochondrial fission resulting in fragmented mitochondria with reduced functionality. This work provides evidence of adaptive early changes in mitochondrial morphology, which results in functional consequences that are dictated by the severity of APAP overdose.

Mitochondrial protein adduct and superoxide generation are prerequisites for early activation of c-jun N-terminal kinase within the cytosol after an acetaminophen overdose in mice

Acetaminophen (APAP) overdose is the most common cause of acute liver failure in the United States and formation of APAP-protein adducts, mitochondrial oxidant stress and activation of the mitogen activated protein (MAP) kinase c-jun N-terminal kinase (JNK) are critical for APAP-induced cell death. However, direct evidence linking these mechanistic features are lacking and were investigated by examining the early temporal course of these changes in mice after 300 mg/kg APAP. Protein adducts were detectable in the liver (0.05-0.1 nmol/mg protein) by 15 and 30 min after APAP, which increased (>500 %) selectively in mitochondria by 60 min. Cytosolic JNK activation was only evident at 60 min, and was significantly attenuated by scavenging superoxide specifically in the cytosol by TEMPO treatment. Treatment of mouse hepatocytes with APAP revealed mitochondrial superoxide generation within 15 min, accompanied by hydrogen peroxide production without change in mitochondrial respiratory function. The oxidant stress preceded JNK activation and its mitochondrial translocation. Inhibitor studies identified the putative source of mitochondrial superoxide as complex III, which released superoxide towards the intermembrane space after APAP resulting in activation of JNK in the cytosol. Our studies provide direct evidence of mechanisms involved in mitochondrial superoxide generation after NAPQI-adduct formation and its activation of the MAP kinase cascade in the cytosol, which are critical features of APAP hepatotoxicity.

Sarcoidosis Presenting in Breast Imaging Clinic With Unilateral Axillary Lymphadenopathy

Sarcoidosis is an idiopathic systemic granulomatous disease that presents with noncaseating granulomas most commonly affecting the lungs and mediastinal lymph nodes. Patients often have nonspecific symptoms, including cough of unknown cause, fever, shortness of breath, fatigue, or weight loss. The diagnosis for sarcoidosis is relatively challenging in the sole presence of swollen lymph nodes and the absence of the aforementioned symptoms. We present a case of unilateral axillary lymphadenopathy found on routine mammography; ultimately proven to be an atypical symptom of sarcoidosis. Our goal is to highlight radiologic features that help distinguish sarcoidosis from potential malignancy.

Impaired protein adduct removal following repeat administration of subtoxic doses of acetaminophen enhances liver injury in fed mice

Acetaminophen (APAP) is a widely used analgesic and is safe at therapeutic doses. However, an overdose of APAP is hepatotoxic and accidental overdoses are increasingly common due to the presence of APAP in several combination medications. Formation of protein adducts (APAP-CYS) is central to APAP-induced liver injury and their removal by autophagy is an essential adaptive response after an acute overdose. Since the typical treatment for conditions such as chronic pain involves multiple doses of APAP over time, this study investigated APAP-induced liver injury after multiple subtoxic doses and examined the role of autophagy in responding to this regimen. Fed male C57BL/6J mice were administered repeated doses (75 mg/kg and 150 mg/kg) of APAP, followed by measurement of adducts within the liver, mitochondria, and in plasma, activation of the MAP kinase JNK, and markers of liver injury. The role of autophagy was investigated by treatment of mice with the autophagy inhibitor, leupeptin. Our data show that multiple treatments at the 150 mg/kg dose of APAP resulted in protein adduct formation in the liver and mitochondria, activation of JNK, and hepatocyte cell death, which was significantly exacerbated by inhibition of autophagy. While repeated dosing with the milder 75 mg/kg dose did not cause mitochondrial protein adduct formation, JNK activation, or liver injury, autophagy inhibition resulted in hepatocyte death even at this lower dose. These data illustrate the importance of adaptive responses such as autophagy in removing protein adducts and preventing liver injury, especially in clinically relevant situations involving repeated dosing with APAP.

Association of the colistin resistance gene mcr-1 with faecal pollution in water environments in Hanoi, Vietnam

Colistin is one of the antibiotics of last resort for human health. However, the dissemination of the plasmid-mediated colistin resistance gene mcr-1 is of great concern globally. In the One Health framework, the environment is an important component for managing antimicrobial resistance. However, little information is available concerning the prevalence of mcr-1 in water environments. We aimed to reveal the prevalence of mcr-1 in different water environments in Hanoi, Vietnam. Quantitative PCR was applied to detect mcr-1 in four urban drainages receiving untreated domestic wastewater, three rivers, five lakes and two groundwater samples. Urban drainages contained higher concentrations of mcr-1, suggesting that urban residents carry the gene. The class 1 integron-integrase gene was identified as a good surrogate of antibiotic resistance genes including mcr-1. A significant correlation was found between the levels of mcr-1 and the human-specific cross-assembly phage, which is an indicator of human faecal pollution. These results indicated that the primary source of mcr-1 in urban water environments is human faeces, which is consistent with the fact that most domestic wastewater is untreated in Hanoi. The control of untreated wastewater is critical for alleviating the spread of mcr-1 in water environments in Vietnam.

A Male Patient With Breast Hamartoma: An Uncommon Finding

Mammary hamartoma is a rare type of breast tumor that is composed of the same elements as normal mammary tissue. This condition is very rare in men. In current literature, there are fewer than five case reports on male breast hamartoma. This benign pathology is under-reported because of several reasons. Since breast tumors are still considered an exclusively female diagnosis and statistically proven to be gynecomastia when arising in men, they are often overlooked. In addition to the uncommon clinical presentation in men, insufficiency of definitive pathologic and radiologic characteristics can make an accurate diagnosis a challenging task. Mammary hamartoma is a benign condition with an excellent prognosis. The following case describes a rare instance of an enlarging mammary hamartoma in a male patient, highlighting the imaging features, pathohistological findings, and clinical management.

Cat Scratch Disease Is an Entity Often Diagnosed in Breast Imaging Department During Axillary Lymph Node Assessment

Cat scratch disease (CSD) is an infectious disease process of generally immunocompetent children and young adults. This infection can be introduced through skin trauma by direct exposure to the saliva of an infected kitten or cat. CSD is typically associated with constitutional symptoms and self-limited regional lymphadenopathy. In the sole presence of swollen lymph nodes, however, the differential diagnosis for CSD is relatively broad, including an active infection, an ongoing inflammatory process, and a metastatic process. CSD can present as axillary lymphadenopathy without typical constitutional symptoms. With proper clinical and laboratory investigation, CSD can be accurately identified and correctly diagnosed, as demonstrated in this case series featuring five symptomatic young adults with axillary lymphadenopathy. Breast imaging clinic specializes in lymph node assessment because metastatic lymphadenopathy is one of the most common presenting signs of breast cancer. Most isolated axillary lymphadenopathy without breast mass is benign reactive lymphadenopathy, but biopsy is necessary to exclude malignancies, such as metastatic lymphadenopathy or lymphoma.

Spontaneously Disappearing Calcifications in the Breast: A Rare Instance Where a Decrease in Size on Mammogram Is Not Good

Spontaneously resolving breast calcification on mammography is a rare radiologic finding. This phenomenon is defined by a decrease in number and/or prominence of breast calcifications on mammogram when compared to prior imaging. The significance of resolving breast calcifications remains unclear, but they have been reported in cases of malignancy. In current literature, patients whose imaging illustrated a decrease in calcifications usually had other concomitant breast complaints. We are presenting a case of invasive ductal carcinoma, in which the patient was asymptomatic on physical examination. Spontaneously resolving breast calcification and lymphadenopathy were the only abnormal findings on screening mammogram.

In vitro Development of Zona Pellucida-free Porcine Zygotes Cultured Individually after Vitrification

BACKGROUND

Cryopreservation of zona pellucida (ZP)-free embryos provides more options for somatic cell nuclear transfer, particularly during handmade cloning.

OBJECTIVE

This study investigated whether the removal of the ZP affects the development of porcine zygotes after vitrification and warming.

MATERIALS AND METHODS

We determined the appropriate volume of the corresponding medium for the individual culture of ZP-intact and -free embryos and evaluated the protection effect of ZP during cryopreservation on the resulting development of the vitrified-warmed zygotes.

RESULTS

The volume of culture medium influenced the development of ZP-intact zygotes, and a volume of 15 µL was most suitable for their development. However, the volume of culture medium did not modify the development of ZP-free zygotes. The removal of the ZP before vitrification did not adversely affect embryonic development or quality of the resulting blastocysts.

CONCLUSION

Our results suggest that the removal of the ZP does not cause detrimental effects to the development of vitrified-warmed zygotes.

Malignant Phyllodes Tumor of the Breast in a 26-year-old Woman

Breast cancer is the most commonly diagnosed cancer and the second leading cause of cancer death in women. Early detection, accurate diagnosis and proper treatment are important prognostic factors due to the wide variety of breast cancer subtypes. This becomes of particular importance with rare breast tumors, which are difficult to diagnose due to their varying presentations. Malignant phyllodes tumor (PT) is one of the rare breast tumors that is difficult to diagnose. First reported in 1838, PT of the breast accounts for less than 1% of all breast masses. Based on histological features, PT is categorized on a spectrum of benign to malignant tumors. High-grade PTs are commonly seen in older patients but can also occur in young patients, as reported in this case of a 26-year-old female. Failure to detect the malignancy early and initiate appropriate treatment can lead to widespread metastasis and poor outcomes.

Clinical and histopathological characterization of paradoxical head and neck erythema in patients with atopic dermatitis treated with dupilumab: a case series

Dupilumab is the first biologic registered for the treatment of atopic dermatitis (AD). We report on seven patients with AD presenting with a paradoxical head and neck erythema that appeared 10-39 weeks after the start of dupilumab treatment. The patients presented with a relatively sharply demarcated, patchy erythema in the head and neck area that showed no or less scaling compared with their usual eczema. Only one patient experienced symptoms of itch and burning, although this was notably different from his pre-existent facial AD. Except for a notable 'red face', eczema on other body parts had greatly improved in six of the seven patients, with a mean numerical rating scale for treatment satisfaction of 9 out of 10 at the time of biopsy. Treatment of the erythema with topical and systemic drugs was unsuccessful. Despite the presence of this erythema, none of our patients discontinued dupilumab treatment. Lesional skin biopsies showed an increased number of ectatic capillaries, and a perivascular lymphohistiocytic infiltration in all patients. In addition, epidermal hyperplasia with elongation of the rete ridges was observed in four patients, resembling a psoriasiform dermatitis. Additional immunohistochemical stainings revealed increased numbers of plasma cells, histiocytes and T lymphocytes. Interestingly, spongiosis was largely absent in all biopsies. We report on patients with AD treated with dupilumab developing a paradoxical erythema in a head and neck distribution. Both clinically and histopathologically we found a heterogeneous response, which was most suggestive of a drug-induced skin reaction.

Psychosocial Stressors, Depression, and Physical Activity among African Americans

Objectives: In this study, we examined how racial discrimination and neighborhood perceptions relate to physical activity and sedentary behavior mediated through depression symptoms. Methods: Data were from the first year of a longitudinal cohort study, Project Creating a Higher Understanding of cancer Research and Community Health (CHURCH), based on a convenience community sample of church-attending African Americans collected between April 2012 and March 2013 (N = 370) in Houston, Texas. Measures included racial discrimination, perceived neighborhood problems and vigilance, depression (CES-D), physical activity (IPAQ-short), and sedentary behavior. Results: Main effects from the structural equation model showed that racial discrimination (b = .20, p < .01) was related to greater depression symptoms. The same pattern emerged for neighborhood problems, but the effect was not significant (b = .20, p = .07). Further, depression symptoms were related to less physical activity (b = -.62, p = .03) and greater sedentary behavior (b = .64, p < .01). Indirect effects showed that depression mediated the relationship between racial discrimination and neighborhood problems on physical activity and sedentary behavior. Conclusions: Depression symptoms are an important mechanism by which racial discrimination and perceived neighborhood problems impact physical activity and sedentary behavior.

Multiple Health Behaviors Engagement in an African American Cohort: Clustering Patterns and Correlates

We investigated class clustering patterns of four behaviors—physical activity, fruit and vegetable (F&V) intake, smoking, and alcohol use—in a faith-based African American cohort. Guided by socio-ecological models, we also examined the psychosocial and neighborhood social environmental factors associated with the clustering patterns. Participants were 1,467 African American adults recruited from a mega church in the metropolitan Houston, TX, in 2008-2009. They completed a survey and health assessment. Latent class analysis and multinomial regression analysis were conducted. Results supported a three-class model: Class 1 was characterized by low physical activity, low F&V intake, and low substance use (smoking and alcohol use). Class 2 was characterized by high physical activity, low F&V intake, and mild drinking. Class 3 seemed to be the healthiest group, characterized by high physical activity, moderate-to-high F&V intake, and low substance use. The probabilities of being included in Classes 1, 2, and 3 were .33, .48, and .19, respectively. Participants in Class 1 (vs. Class 3) reported lower physical activity norm ( p < .001) and higher smoking norm ( p = .002) and lower neighborhood social cohesion ( p = .031). Participants in Class 2 (vs. Class 3) reported higher cancer risk perception ( p < .001), lower F&V norm ( p = .022), lower physical activity norm ( p < .001), higher smoking norm ( p < .001), and lower social cohesion ( p = .047). As health behaviors are clustered together, future interventions for African Americans may consider targeting multiple health behaviors instead of targeting a single health behavior. Interventions addressing social norm and neighborhood social cohesion may enhance multiple health behaviors engagement in this population.

Abstract P5-15-03: Imaging is not indicated in staging of asymptomatic patients with early breast cancer – Are we following current recommendations?

Breast cancer is the most common malignancy in women with estimated care costs of $20.50 billion/year by 2020. In 2012, ASCO released the Choosing Wisely Initiative which recommended against the use of routine staging imaging in patients with newly diagnosed early stage breast cancer. We examined physician's adherence rate and factors associated with non-adherence to current guidelines in patients with early stage breast cencer treated within a large urban health care system.

We identified all women with stage I-II breast cancer diagnosed between January 1, 2014 and December 31, 2015 from the Cancer Registry of the Mount Sinai Health System. Patients with history of prior malignancy or symptom-triggered imaging were excluded. Demographic, clinical and treatment related factors were collected. Medical records were reviewed to identify patients who had routine staging scans. Data of initial and follow-up imaging over 1-year period were collected. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated from logistic regression models.

Among 917 breast cancer patients, the median age at diagnosis was 59 years (range 26-98). One hundred seventy one patients (18.6%) had routine staging imaging with a mean number of initial scans of 1.48. Eighty-two patients (48%) had at least 1 subsequent scan in the 1-year follow up (range 1-4 scans/year). PET/CT was the most frequent modality (49%), followed by CT scan (33%). The medical oncologist was the ordering provider in 50.3% of the cases and surgical oncologist in 43.2%. Routine staging scans identified no cases of metastatic disease. False-positive findings were identified in 49.7% and incidental findings in 9.3% of cases. Total cost of imaging in this group was $3990/patient. Young age (&lt;50 years old), tumor size &gt;2cm, positive lymph nodes, and triple negative disease were associated with presence of routine staging scans on univariate and multivariate analysis (Table 1).

Our study highlights the prevalence of unnecessary staging scans in up to 18.6% of patients with early stage I-II breast cancer. Routine imaging resulted in increased radiation exposure, multiple subsequent imaging, and increased economical burden particularly for those of young age, T2 tumors, positive lymph nodes, and triple negative disease. Further educational efforts are needed to avoid unnecessary scans in patients with early stage breast cancer and improve high-value practices among medical and surgical oncologists.

Factors associated with routine staging scans in early breast cancer OR95% CIp-value Univariate Analysis:   Age &lt; 501.691.17-2.420.005T2 tumors4.353.01-6.28&lt;0.0001Positive lymph nodes5.073.43-7.51&lt;0.0001Triple negative disease2.941.86-4.63&lt;0.0001 Multivariate Analysis:   Age &lt; 501.571.03-2.390.037T2 tumors3.472.34 -5.17&lt;0.0001Positive lymph nodes4.042.64-6.18&lt;0.0001Triple negative disease2.991.76-5.05&lt;0.0001

Citation Format: Velazquez AI, Nguyen NT, Rodriguez-Bonilla C, Shao T. Imaging is not indicated in staging of asymptomatic patients with early breast cancer – Are we following current recommendations? [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-15-03.

Changes in iron availability in Arabidopsis are rapidly sensed in the leaf vasculature and impaired sensing leads to opposite transcriptional programs in leaves and roots

The OLIGOPEPTIDE TRANSPORTER 3 (OPT3) has recently been identified as a component of the systemic network mediating iron (Fe) deficiency responses in Arabidopsis. Reduced expression of OPT3 induces an over accumulation of Fe in roots and leaves, due in part by an elevated expression of the IRON-REGULATED TRANSPORTER 1. Here we show however, that opt3 leaves display a transcriptional program consistent with an Fe overload, suggesting that Fe excess is properly sensed in opt3 leaves and that the OPT3-mediated shoot-to-root signaling is critical to prevent a systemic Fe overload. We also took advantage of the tissue-specific localization of OPT3, together with other Fe-responsive genes, to determine the timing and location of early transcriptional events during Fe limitation and resupply. Our results show that the leaf vasculature responds more rapidly than roots to both Fe deprivation and resupply, suggesting that the leaf vasculature is within the first tissues that sense and respond to changes in Fe availability. Our data highlight the importance of the leaf vasculature in Fe homeostasis by sensing changes in apoplastic levels of Fe coming through the xylem and relaying this information back to roots via the phloem to regulate Fe uptake at the root level.

Nitrogen Fixation Genes and Nitrogenase Activity of the Non-Heterocystous Cyanobacterium Thermoleptolyngbya sp. O-77

Cyanobacteria are widely distributed in marine, aquatic, and terrestrial ecosystems, and play an important role in the global nitrogen cycle. In the present study, we examined the genome sequence of the thermophilic non-heterocystous N₂-fixing cyanobacterium, Thermoleptolyngbya sp. O-77 (formerly known as Leptolyngbya sp. O-77) and characterized its nitrogenase activity. The genome of this cyanobacterial strain O-77 consists of a single chromosome containing a nitrogen fixation gene cluster. A phylogenetic analysis indicated that the NifH amino acid sequence from strain O-77 was clustered with those from a group of mesophilic species: the highest identity was found in Leptolyngbya sp. KIOST-1 (97.9% sequence identity). The nitrogenase activity of O-77 cells was dependent on illumination, whereas a high intensity of light of 40 μmol m⁻² s⁻¹ suppressed the effects of illumination.

Hydroponics: A Versatile System to Study Nutrient Allocation and Plant Responses to Nutrient Availability and Exposure to Toxic Elements

Hydroponic systems have been utilized as one of the standard methods for plant biology research and are also used in commercial production for several crops, including lettuce and tomato. Within the plant research community, numerous hydroponic systems have been designed to study plant responses to biotic and abiotic stresses. Here we present a hydroponic protocol that can be easily implemented in laboratories interested in pursuing studies on plant mineral nutrition. This protocol describes the hydroponic system set up in detail and the preparation of plant material for successful experiments. Most of the materials described in this protocol can be found outside scientific supply companies, making the set up for hydroponic experiments less expensive and convenient. The use of a hydroponic growth system is most advantageous in situations where the nutrient media need to be well controlled and when intact roots need to be harvested for downstream applications. We also demonstrate how nutrient concentrations can be modified to induce plant responses to both essential nutrients and toxic non-essential elements.

Antibacterial activity of Litsea cubeba (Lauraceae, May Chang) and its effects on the biological response of common carp Cyprinus carpio challenged with Aeromonas hydrophila

AIMS

The aims of this study were to characterize the antibacterial activity and the chemotype of Litsea cubeba leaf essential oil (EO) harvested in North Vietnam and to investigate the biological effects induced by the leaf powder on growth, nonspecific immunity and survival of common carp (Cyprinus carpio) challenged with Aeromonas hydrophila.

METHODS AND RESULTS

The EO showed the prevalence of linalool (95%, n = 5). It was bactericidal against the majority of tested strains, with minimum inhibitory concentrations ranging from 0·72 to 2·89 mg ml(-1) (Aer. hydrophila, Edwarsiella tarda, Vibrio furnissii, Vibrio parahaemolyticus, Streptococcus garvieae, Escherichia coli, Salmonella Typhimurium). The fish was fed with 0 (control), 2, 4 and 8% leaf powder supplementation diets for 21 days. Nonspecific immunity parameters (lysozyme, haemolytic and bactericidal activities of plasma) were assessed 21 days after feeding period and before the experimental infection. Weight gain, specific growth rate and feed conversion ratio were improved by supplementation of L. cubeba in a dose-related manner, and a significant difference appeared at the highest dose (8%) when compared to the control. The increase in plasma lysozyme was significant for all the treated groups. Haemolysis activity was higher for the groups fed with 4 and 8% plant powder. Antibacterial activity increased significantly for the 8% dose only.

CONCLUSIONS

Litsea cubeba leaf powder increased nonspecific immunity of carps in dose-related manner. After infection with Aer. hydrophila, survivals of fish fed with 4 and 8% L. cubeba doses were significantly higher than those fed with 2% dose and the control.

SIGNIFICANCE AND IMPACT OF THE STUDY

A range of 4-8% L. cubeba leaf powder supplementation diet (from specific linalool-rich chemotype) can be used in aquaculture to reduce antibiotic burden and impacts of diseases caused by Aer. hydrophila.

[MOLECULAR-GENETIC ANALYSIS OF MICROORGANISMS WITH INTRAEPITHELIAL INVASION ISOLATED FROM PATIENTS WITH COLORECTAL CANCER]

The facultative aerobic bacteria isolated from the mucosa of rectum in patients with colorectal cancer in the zone of malignant tumor and neighboring normal mucosa was studied using molecular-genetic methods. The species attribution of bacteria was implemented using the cultural-morphological analysis and sequencing of the 16S rRNA locus. The microorganisms with the intraepithelial invasion to rectal mucosa isolated were identified as representatives of the adherent-invasive (AIEC) subgroup of Escherichia coli and species Klebsiella pneumonia. The molecular analysis by genetic determinants controlling adhesive, hemolytic, and toxigenic activity revealed that some bacterial isolates were able to produce toxins with potential cancerogenic activity (e.g., colibactin and cytotoxic necrotic factor I). Certain bacterial species isolated from malignant and normal rectum epithelium of the same patient demonstrated no difference between analyzed factors of toxigenicity.

Financial strain and smoking cessation among men and women within a self-guided quit attempt

INTRODUCTION

Financial strain, defined as an unfavorable asset-to-needs ratio, has been associated with reduced odds of smoking cessation in the context of a structured clinical study providing cessation assistance. This study reports on a secondary data analysis that assessed the association of financial strain and biochemically-verified smoking abstinence within a structured clinical study of smokers making a self-guided cessation attempt.

METHODS

Participants (N=58; 65.5% men) were enrolled in a study about anxiety sensitivity and smoking cessation whereby they were instructed to initiate a self-guided quit attempt. Relations between financial strain and biochemically-verified smoking abstinence on the quit day and at Days 3, 7, 14, 28, and 90 post-quit were assessed using generalized estimating equations controlling for age, sex, race, education, partner status, pre-quit cigarettes smoked per day, and time.

RESULTS

Associations between financial strain and abstinence in the whole sample were marginal (aOR=.94, 95% CI=.87-1.01, observations=293; p=.07). However, sex was a significant moderator: greater financial strain was associated with lower odds of abstinence for men (aOR=.90, 95% CI=.80-1.00, observations=201; p=.05), but not women (aOR=1.05, 95% CI=.91-1.21, observations=92; p=.48).

CONCLUSIONS

Results indicated that financial strain was associated with lower odds of cessation among men undergoing a self-guided quit attempt in the context of a structured clinical study. These data suggest that financial strain may be an important socioeconomic determinant of smoking cessation and support its relevance for better understanding socioeconomic-based smoking-related health disparities. Future work may benefit by exploring sex-specific models of financial strain in the context of smoking cessation.

Dean-flow-coupled elasto-inertial three-dimensional particle focusing under viscoelastic flow in a straight channel with asymmetrical expansion-contraction cavity arrays

In this paper, 3D particle focusing in a straight channel with asymmetrical expansion-contraction cavity arrays (ECCA channel) is achieved by exploiting the dean-flow-coupled elasto-inertial effects. First, the mechanism of particle focusing in both Newtonian and non-Newtonian fluids was introduced. Then particle focusing was demonstrated experimentally in this channel with Newtonian and non-Newtonian fluids using three different sized particles (3.2 μm, 4.8 μm, and 13 μm), respectively. Also, the effects of dean flow (or secondary flow) induced by expansion-contraction cavity arrays were highlighted by comparing the particle distributions in a single straight rectangular channel with that in the ECCA channel. Finally, the influences of flow rates and distances from the inlet on focusing performance in the ECCA channel were studied. The results show that in the ECCA channel particles are focused on the cavity side in Newtonian fluid due to the synthesis effects of inertial and dean-drag force, whereas the particles are focused on the opposite cavity side in non-Newtonian fluid due to the addition of viscoelastic force. Compared with the focusing performance in Newtonian fluid, the particles are more easily and better focused in non-Newtonian fluid. Besides, the Dean flow in visco-elastic fluid in the ECCA channel improves the particle focusing performance compared with that in a straight channel. A further advantage is three-dimensional (3D) particle focusing that in non-Newtonian fluid is realized according to the lateral side view of the channel while only two-dimensional (2D) particle focusing can be achieved in Newtonian fluid. Conclusively, this novel Dean-flow-coupled elasto-inertial microfluidic device could offer a continuous, sheathless, and high throughput (>10 000 s(-1)) 3D focusing performance, which may be valuable in various applications from high speed flow cytometry to cell counting, sorting, and analysis.

Synthesis of inorganic structural isomers by diffusion-constrained self-assembly of designed precursors: a novel type of isomerism

The structure of precursors is used to control the formation of six possible structural isomers that contain four structural units of PbSe and four structural units of NbSe2: [(PbSe)1.14]4[NbSe2]4, [(PbSe)1.14]3[NbSe2]3[(PbSe)1.14]1[NbSe2]1, [(PbSe)1.14]3[NbSe2]2[(PbSe)1.14]1[NbSe2]2, [(PbSe)1.14]2[NbSe2]3[(PbSe)1.14]2[NbSe2]1, [(PbSe)1.14]2[NbSe2]2[(PbSe)1.14]1[NbSe2]1[(PbSe)1.14]1[NbSe2]1, [(PbSe)1.14]2[NbSe2]1[(PbSe)1.14]1[NbSe2]2[(PbSe)1.14]1[NbSe2]1. The electrical properties of these compounds vary with the nanoarchitecture. For each pair of constituents, over 20,000 new compounds, each with a specific nanoarchitecture, are possible with the number of structural units equal to 10 or less. This provides opportunities to systematically correlate structure with properties and hence optimize performance.

Nanoalloying bulk-immiscible iridium and palladium inhibits hydride formation and promotes catalytic performances

The hydrogen sorption properties of oxide-supported Ir-Pd nanoalloys have been determined for the first time, and correlated with their catalytic behavior. The addition of Ir to Pd suppresses hydride formation and leads to improved catalytic performances with respect to pure metals in the preferential oxidation of CO in H2 excess (PROX).

Basal and bolus insulin requirements in children, adolescents, and young adults with type 1 diabetes mellitus on continuous subcutaneous insulin infusion (CSII): effects of age and puberty

OBJECTIVE

Guidelines for insulin dosing, including the insulin to carbohydrate ratio (I/C), insulin sensitivity factor (ISF), and basal/bolus ratio guidelines, have been well established for adults with type 1 diabetes mellitus (T1DM). However, clinical experience suggests that these guidelines are not appropriate for children. The purpose of this study was to determine the continuous subcutaneous insulin infusion (CSII) settings in children with T1DM at different ages and stages of puberty.

METHODS

A total of 154 patients data between the ages of 3 and 21 years with well-controlled T1DM according to American Diabetes Association guidelines were reviewed. Only patients on CSII who were not in the honeymoon period were included.

RESULTS

Patients were divided into 8 groups according to age, gender, and/or pubertal stage. Insulin requirements increased with puberty in both sexes (0.69, 0.97, and 0.90 U/kg/day in children <7 years of age, midpubertal girls, and late-pubertal boys, respectively). Basal insulin requirement was lowest in the youngest group (34%; P<.01). The youngest group had the lowest I/C prediction factor (PF) (mean, 315.7 ± 79.4; P<.01 with all groups), and the ISF-PF was higher than that of the oldest group (mean, 2,588.3 ± 1,101.8; P<.01).

CONCLUSION

CSII dose calculations vary with age and pubertal status in children with T1DM. These differences must be considered when calculating CSII dosing, especially for younger children.

Financial strain and cancer risk behaviors among African Americans

BACKGROUND

African Americans suffer disproportionately from the adverse consequences of behavioral risk factors for cancer relative to other ethnic groups. Recent studies have assessed how financial strain might uniquely contribute to engagement in modifiable behavioral risk factors for cancer, but not among African Americans. The current study examined associations between financial strain and modifiable cancer risk factors (smoking, at-risk alcohol use, overweight/obesity, insufficient physical activity, inadequate fruit and vegetable intake, and multiple risk factors) among 1,278 African American adults (age, 46.5 ± 12.6 years; 77% female) and explored potential mediators (stress and depressive symptoms) of those associations.

METHODS

Logistic regression models were used to examine associations between financial strain and cancer risk factors. Analyses were adjusted for age, sex, partner status, income, educational level, and employment status. Analyses involving overweight/obesity status additionally controlled for fruit and vegetable intake and physical activity. Nonparametric bootstrapping procedures were used to assess mediation.

RESULTS

Greater financial strain was associated with greater odds of insufficient physical activity (P < 0.003) and smoking (P = 0.005) and was positively associated with the total number of cancer risk factors (P < 0.0001). There was a significant indirect effect of both stress and depressive symptoms on the relations of financial strain with physical inactivity and multiple risk factors, respectively.

CONCLUSIONS

Future interventions aimed at reducing cancer disparities should focus on African Americans experiencing higher financial strain while addressing their stress and depressive symptoms.

IMPACT

Longitudinal studies are needed to assess the temporal and causal relations between financial strain and modifiable behavioral cancer risk factors among African Americans.

Molybdenum-containing membrane-bound formate dehydrogenase isolated from Citrobacter sp. S-77 having high stability against oxygen, pH, and temperature

Membrane-bound formate dehydrogenase (FDH) was purified to homogeneity from a facultative anaerobic bacterium Citrobacter sp. S-77. The FDH from Citrobacter sp. S-77 (FDHS77) was a monomer with molecular mass of approximately 150 kDa. On SDS-PAGE, the purified FDHS77 showed as three different protein bands with molecular mass of approximately 95, 87, and 32 kDa, respectively. Based on the N-terminal amino acid sequence analysis, the sequence alignments observed for the 87 kDa protein band were identical to that of the large subunit of 95 kDa, indicating that the purified FDHS77 consisted of two subunits; a 95 kDa large subunit and a 32 kDa small subunit. The purified FDHS77 in this purification did not contain a heme b subunit, but the FDHS77 showed significant activity for formate oxidation, determined by the Vmax of 30.4 U/mg using benzyl viologen as an electron acceptor. The EPR and ICP-MS spectra indicate that the FDHS77 is a molybdenum-containing enzyme, displaying a remarkable O2-stability along with thermostability and pH resistance. This is the first report of the purification and characterization of a FDH from Citrobacter species.

Components of the diet associated with child adiposity: a cross-sectional study

OBJECTIVE

This study sought to determine which components of youths' diets were related to adiposity while controlling for potential often-neglected confounders such as moderate to vigorous physical activity (MVPA) and dietary reporting error. Secondary goals of this study were to determine the extent to which MVPA confounded the associations between diet and adiposity and whether associations between diet and adiposity would differ depending on reporting error.

METHODS

An ethnically diverse urban sample of 342 children aged 9-10 years and 323 adolescents aged 17-18 years were recruited for this cross-sectional study. Body mass index (BMI) and waist circumference (WC) were measured in the school; dietary assessment included three 24-hour recalls via telephone in the evenings, and MVPA assessment included 5 days of accelerometry. Over (n = 68), under (n = 250), or plausible (n = 347) dietary intake reporters were identified with the Huang calculation method. Linear regression assessed the relationship between adiposity indicators (BMI z-score and WC) and components of the diet (energy intake, food groups, macronutrients) after controlling for reporting error, demographic variables, and MVPA.

RESULTS

When dietary reporting error and potential confounders such as MVPA and demographic variables were controlled, energy intake (EI), vegetables, refined grains, total fat, total protein, and total carbohydrate were positively related to BMI z-score and WC and artificially sweetened beverages to WC. MVPA was a significant confounder. For BMI z-score, but not WC, relationships and strength of these relationships differed depending on dietary reporting error group (plausible, underreporter, overreporter).

CONCLUSIONS

Among plausible reporters, as expected, EI, refined grains, and all macronutrients were positively related to adiposity; however, artificially sweetened beverages and vegetables, which are low-energy-dense foods, were also positively related to adiposity. Reporting error interfered with associations between diet and BMI z-score but not WC, suggesting WC is a more robust measure of adiposity in relation to diet.

Cloning of the RNase H genes from a metagenomic DNA library: identification of a new type 1 RNase H without a typical active-site motif

AIMS

The study aimed to combine a metagenomics approach with complementary genetics to identify novel bacterial genes with orthologous functions, with the identification of novel RNase H genes as a test case.

METHODS AND RESULTS

A metagenomic DNA library was prepared from leaf-and-branch compost and used to screen for the RNase H genes by their abilities to complement the temperature-sensitive growth phenotype of the rnhA mutant Escherichia coli strain MIC3001. Determination of the nucleotide sequences of the cloned DNA fragments allowed us to identify 12 different genes encoding type 1 RNases H. Eleven of them encode novel RNases H, which show 40-72% amino acid sequence identities to those available from database. One of them lacks a typical DEDD/E active-site motif, which is almost fully conserved in various RNases H.

CONCLUSIONS

Functional screening of environmental DNA without cultivation of microbes is a useful procedure to isolate novel RNase H genes.

SIGNIFICANCE AND IMPACT OF THE STUDY

One of the identified RNase H genes had no sequence similarity to a previously assumed conserved motif, suggesting multiple catalytic mechanisms exist. This test case illustrates that metagenomics combined with complementary genetics can identify novel genes that are orthologous without sequence similarity to those from cultivated bacteria.