bluuebunny/crossref_metadata_2025 huggingface dataset:
Plastidial (p)ppGpp Synthesis by the Ca2+-Dependent RelA–SpoT Homolog Regulates the Adaptation of Chloroplast Gene Expression to Darkness in Arabidopsis
Authors: Ono Sumire , Suzuki Sae , Ito Doshun , Tagawa Shota , Shiina Takashi , Masuda Shinji
Published: September 2020

In bacteria, the hyper-phosphorylated nucleotide, guanosine 3′,5′-bis(pyrophosphate) (ppGpp), functions as a secondary messenger under stringent conditions. ppGpp levels are controlled by two distinct enzymes, namely RelA and SpoT, in Escherichia coli. RelA–SpoT homologs (RSHs) are also conserved in plants where they function in the plastids. The model plant Arabidopsis thaliana contains four RSHs: RSH1, RSH2, RSH3 and Ca2+-dependent RSH (CRSH). Genetic characterizations of RSH1, RSH2 and RSH3 were undertaken, which showed that the ppGpp-dependent plastidial stringent response significantly influences plant growth and stress acclimation. However, the physiological significance of CRSH-dependent ppGpp synthesis remains unclear, as no crsh-null mutant has been available. Here, to investigate the function of CRSH, a crsh-knockout mutant of Arabidopsis was constructed using a site-specific gene-editing technique, and its phenotype was characterized. A transient increase in ppGpp was observed for 30 min in the wild type (WT) after the light-to-dark transition, but this increase was not observed in the crsh mutant. Similar analyses were performed with the rsh2-rsh3 double and rsh1-rsh2-rsh3 triple mutants and showed that the transient increments of ppGpp in the mutants were higher than those in the WT. The increase in ppGpp in the WT and rsh2 rsh3 accompanied decrements in the mRNA levels of some plastidial genes transcribed by the plastid-encoded plastid RNA polymerase. These results indicate that the transient increase in ppGpp at night is due to CRSH-dependent ppGpp synthesis and that the ppGpp level is maintained by the hydrolytic activities of RSH1, RSH2 and RSH3 to accustom plastidial gene expression to darkness.
Improving Veteran Access to Integrated Management of Back Pain (AIM-Back): Protocol for an Embedded Pragmatic Cluster-Randomized Trial
Authors: George Steven Z , Coffman Cynthia J , Allen Kelli D , Lentz Trevor A , Choate Ashley , Goode Adam P , Simon Corey B , Grubber Janet M , King Heather , Cook Chad E , Keefe Francis J , Ballengee Lindsay A , Naylor Jennifer , Brothers Joseph Leo , Stanwyck Catherine , Alkon Aviel , Hastings Susan N
Published: September 2020

Background

Coordinated efforts between the National Institutes of Health, the Department of Defense, and the Department of Veterans Affairs have built the capacity for large-scale clinical research investigating the effectiveness of nonpharmacologic pain treatments. This is an encouraging development; however, what constitutes best practice for nonpharmacologic management of low back pain (LBP) is largely unknown.

Design

The Improving Veteran Access to Integrated Management of Back Pain (AIM-Back) trial is an embedded pragmatic cluster-randomized trial that will examine the effectiveness of two different care pathways for LBP. Sixteen primary care clinics will be randomized 1:1 to receive training in delivery of 1) an integrated sequenced-care pathway or 2) a coordinated pain navigator pathway. Primary outcomes are pain interference and physical function (Patient-Reported Outcomes Measurement Information System Short Form [PROMIS-SF]) collected in the electronic health record at 3 months (n=1,680). A subset of veteran participants (n=848) have consented to complete additional surveys at baseline and at 3, 6, and 12 months for supplementary pain and other measures.

AIM-Back care pathways will be tested for effectiveness, and treatment heterogeneity will be investigated to identify which veterans may respond best to a given pathway. Health care utilization patterns (including opioid use) will also be compared between care pathways. Therefore, the AIM-Back trial will provide important information that can inform the future delivery of nonpharmacologic treatment of LBP.
“A Necessary Investment in Future Health”: Perceptions of Physical Activity Maintenance Among People With Rheumatoid Arthritis
Authors: Swärdh Emma , Nordgren Birgitta , Opava Christina H , Demmelmaier Ingrid
Published: September 2020

Objective

A few studies with a qualitative design have addressed physical activity (PA) maintenance in people with rheumatoid arthritis (RA), but none of them focused specifically on maintenance of PA according to public health recommendations. The purpose of this study was to describe perceptions of PA maintenance during the second year of an outsourced 2-year support program among people with RA.

Methods

For this descriptive design with a qualitative inductive approach, semi-structured interviews were conducted with 18 participants with RA (3 men and 15 women). Variation in age, disease duration, activity limitation, pain, levels of PA, and PA maintenance was targeted through strategic sampling. Qualitative content analysis was used, and a pattern of theme, subthemes, and categories was constructed based on the participants’ perceptions of PA maintenance.

Results

A main overarching theme, “A necessary investment in future health”—with 3 subthemes of dedication, awareness, and affinity—was identified as participants’ perceptions of PA maintenance. Eight categories further described are a changed mindset, habits, commitments, monitoring, insights in PA, health gains, social support, and PA context.

Conclusions

PA according to public health recommendations was perceived as a true investment in future health and wellness requiring dedication, awareness, and affinity. To promote PA maintenance, physical therapists working with people with chronic conditions should consider strengthening these prerequisites by targeting patients’ negative attitudes to PA, supporting their creation of PA habits to incorporate in daily routines, introducing monitoring of PA intensity, supporting development of PA self-regulation skills, and providing suitable gym facilities with the possibility of peer support.
Predictors of Treatment-Resistant and Clozapine-Resistant Schizophrenia: A 12-Year Follow-up Study of First-Episode Schizophrenia-Spectrum Disorders
Authors: Chan Sherry Kit Wa , Chan Hei Yan Veronica , Honer William G , Bastiampillai Tarun , Suen Yi Nam , Yeung Wai Song , Lam Ming , Lee Wing King , Ng Roger Man King , Hui Christy Lai Ming , Chang Wing Chung , Lee Edwin Ho Ming , Chen Eric Yu Hai
Published: September 2020

Studies on the long-term development and early predictors of treatment-resistant schizophrenia (TRS) and clozapine-resistant TRS (CR-TRS) in patients with first-episode schizophrenia-spectrum disorders (FES) are limited and have not considered the impact of early intervention services (EIS). This study aimed to explore the development of TRS and CR-TRS among patients with FES over 12 years of follow-up. Of the 1234 patients with FES, 15% developed TRS. A total of 450 patients with schizophrenia or schizoaffective disorder were included in a nested case-control study (157 TRS and 293 non-TRS). Younger age of onset, poorer premorbid social adjustment during adulthood, longer duration of first episode, a greater number of relapses, and a higher antipsychotic dose in the first 24 months were associated with earlier TRS. CR-TRS patients, constituting 25% of TRS patients, had a poorer premorbid social adjustment in late adolescence and longer delay before clozapine initiation compared with non-CR-TRS. CR-TRS had poorer clinical and functional outcomes at 12-year follow-up. However, TRS patients on clozapine had a lower mortality rate compared with non-TRS patients. EIS did not have a significant impact on the development of TRS, but patients in the EIS group had a shorter delay of clozapine initiation. Results suggested that neurodevelopmental factors, early clinical characteristics, and requirement for higher antipsychotic dose may be associated with TRS development, highlighting multiple pathways leading to this form of illness. Specific interventions including relapse prevention and early initiation of clozapine during the early course of illness may reduce the rate of TRS and improve patient outcomes.
Neurological Soft Signs Predict Auditory Verbal Hallucinations in Patients With Schizophrenia
Authors: Wolf Robert C , Rashidi Mahmoud , Schmitgen Mike M , Fritze Stefan , Sambataro Fabio , Kubera Katharina M , Hirjak Dusan
Published: September 2020

Neurological soft signs (NSS) are well documented in individuals with schizophrenia (SZ), yet so far, the relationship between NSS and specific symptom expression is unclear. We studied 76 SZ patients using magnetic resonance imaging (MRI) to determine associations between NSS, positive symptoms, gray matter volume (GMV), and neural activity at rest. SZ patients were hypothesis-driven stratified according to the presence or absence of auditory verbal hallucinations (AVH; n = 34 without vs 42 with AVH) according to the Brief Psychiatric Rating Scale. Structural MRI data were analyzed using voxel-based morphometry, whereas intrinsic neural activity was investigated using regional homogeneity (ReHo) measures. Using ANCOVA, AVH patients showed significantly higher NSS in motor and integrative functions (IF) compared with non-hallucinating (nAVH) patients. Partial correlation revealed that NSS IF were positively associated with AVH symptom severity in AVH patients. Such associations were not confirmed for delusions. In region-of-interest ANCOVAs comprising the left middle and superior temporal gyri, right paracentral lobule, and right inferior parietal lobule (IPL) structure and function, significant differences between AVH and nAVH subgroups were not detected. In a binary logistic regression model, IF scores and right IPL ReHo were significant predictors of AVH. These data suggest significant interrelationships between sensorimotor integration abilities, brain structure and function, and AVH symptom expression.
Adintoviruses: a proposed animal-tropic family of midsize eukaryotic linear dsDNA (MELD) viruses
Authors: Starrett Gabriel J , Tisza Michael J , Welch Nicole L , Belford Anna K , Peretti Alberto , Pastrana Diana V , Buck Christopher B
Published: September 2020

Polintons (also known as Mavericks) were initially identified as a widespread class of eukaryotic transposons named for their hallmark type B DNA polymerase and retrovirus-like integrase genes. It has since been recognized that many polintons encode possible capsid proteins and viral genome-packaging ATPases similar to those of a diverse range of double-stranded DNA viruses. This supports the inference that at least some polintons are actually viruses capable of cell-to-cell spread. At present, there are no polinton-associated capsid protein genes annotated in public sequence databases. To rectify this deficiency, we used a data-mining approach to investigate the distribution and gene content of polinton-like elements and related DNA viruses in animal genomic and metagenomic sequence datasets. The results define a discrete family-like clade of viruses with two genus-level divisions. We propose the family name Adintoviridae, connoting similarities to adenovirus virion proteins and the presence of a retrovirus-like integrase gene. Although adintovirus-class PolB sequences were detected in datasets for fungi and various unicellular eukaryotes, sequences resembling adintovirus virion proteins and accessory genes appear to be restricted to animals. Degraded adintovirus sequences are endogenized into the germlines of a wide range of animals, including humans.
New developments in respiratory medicine: a primary immunodeficiency perspective
Authors: Ng Kher , Hurst John R.
Published: September 2020

Purpose of review

To consider recent developments in respiratory medicine that are of relevance to clinicians caring for adults affected by primary immunodeficiency disorders.

Recent findings

We consider impulse oscillometry, new bronchoscopic techniques for sampling, MRI and PET, the concept of the human airway microbiome, and new treatment approaches for bronchiectasis and interstitial lung disease to better understand the future of respiratory care for people with PID.

New approaches to the diagnosis and management of respiratory manifestations of PID have been driven by better understanding of the lung in health and disease, progress in imaging and sampling modalities, and new therapeutics.
Learning During and From a Crisis: The Student-Led Development of a COVID-19 Curriculum
Authors: Kochis Michael , Goessling Wolfram
Published: September 2020

Problem

The speed and scope of the upheaval that COVID-19 inflicted on medical education made innovation a necessity. While medical students wanted high-quality, consolidated educational resources on COVID-19, the medical school faculty who typically produced such resources were increasingly burdened with clinical, administrative, and personal commitments. However, students eager to contribute to the pandemic response were well suited to create these instructional materials for their peers.

Approach

In mid-March 2020, a group of students at Harvard Medical School came together to synthesize the key facts and collate the best existing educational materials about the COVID-19 pandemic into a unified learning resource. The materials were faculty reviewed and shared freely online. The curriculum now contains 8 modules that are updated regularly. Throughout this process, the student authors prioritized accessibility, iterative improvement, and effective pedagogy.

Outcomes

To date, nearly 80,000 users from 132 countries have accessed the curriculum. It has been referenced or incorporated into courses at Harvard Medical School and more than 30 other medical schools across the country. About 40% of all users are from outside the United States, and the materials have been translated into 28 languages. This effort has spurred a number of other educational initiatives led by medical student groups in the United States and abroad.

Next Steps

As understanding of the COVID-19 pandemic is constantly changing, the student authors’ immediate goal is to keep the curriculum up to date in the months to come. They plan to maintain existing partnerships with medical schools and student groups around the world while pursuing new opportunities to expand the curriculum’s reach, provide education, and build community. Students and educators alike should leverage student-driven education efforts to benefit other learners both within and, importantly, beyond their institutions.
Outcomes of Liquifying PLDLLA Suture Anchor for Lateral Ligament Reconstruction of the Ankle
Authors: Erwood Amalie A. , Wilson Jacob M. , Mignemi Danielle , Bariteau Jason T.
Published: September 2020

Liquifying poly-DL lactic acid (PLDLLA) suture anchors represent a novel fixation technique in lateral ligament reconstruction. Biomechanical testing has demonstrated that these bone-welding anchors have significant resistance to pullout in cancellous bone. To determine if this superior strength translates to improved clinical outcomes, an initial evaluation of complications and patient-reported outcomes of ultrasound-activated anchor fixation was conducted. A chart review of prospectively collected data were conducted on 8 patients who underwent a modified Broström technique using bone-welding technology for lateral ligament fixation. All surgeries were performed by a single surgeon, for similar clinical indications, and utilized 1 or 2 ultrasound-activated anchors. Clinical data and postoperative patient-reported outcomes (visual analog scale and Short Form Health Survey-36) were collected over 1 year and analyzed. Preoperative, 6-month, and 1-year visual analog scale scores were 4.3±1.9 (range, 2 to 7), 0.7±1.5 (range, 0 to 4) (P=0.004), and 0±0 (P=0.002), respectively. The Short Form Health Survey-36 preoperative, 6-month, and 1-year physical functioning scale scores were 61.3±31.3 (range, 15 to 100), 87.5±16.9 (range, 50 to 100) (P=0.024), and 98.6±2.4 (range, 95 to 100) (P=0.0096), respectively. There were no major complications. Use of ultrasonic-activated anchors demonstrated improvement in patient-reported outcomes with a low incidence of clinical complications. Future work is needed to confirm these findings in a larger sample and directly compare these anchors with the current leading fixation devices.

Level of Evidence: Diagnostic Level IV, Case Series. See Instructions for Authors for a complete description of levels of evidence.
Proximal Junctional Kyphosis and Proximal Junctional Failure in the Treatment for Adult Spinal Deformity: Definitions and Epidemiology
Authors: Watanabe Kota , Yagi Mitsuru , Fujita Nobuyuki , Suzuki Satoshi , Tsuji Osahiko , Nagoshi Narihito , Okada Eijiro , Nakamura Masaya , Matumoto Morio
Published: September 2020

Proximal junctional failure (PJF) is considered to be one of the most serious complications after correction surgery with a long construct for adult spinal deformity. Proximal junctional kyphosis (PJK) was first defined as an angle between the lower endplate of the uppermost instrumented vertebra (UIV) and the upper endplate of UIV+2 of 10 degrees or greater, and at least 10 degrees greater than the preoperative measurement. Although PJK has been found to cause no significant clinical symptoms, PJF is regarded as a pathology associated with a fracture of UIV or UIV+1, posterior osseoligamentous disruption, or a pullout of instrumentation at the UIV, and may require revision surgery. The incidence of PJK or PJF is influenced by a variety of factors including the pathology of the deformity, surgical procedures and spinal construct, status of osteoporosis, prophylactic procedures, and the follow-up period. Therefore, the reported incidences of PJK vary widely, from 7.7% to 56%, whereas those of PJF vary widely, from 1.4% to 35%.
Type 1 Plasminogen Deficiency With Pulmonary Involvement: Novel Treatment and Novel Mutation
Authors: Hangul Melih , Tuzuner Ahmet B. , Somekh Ido , Klein Christoph , Patiroglu Turkan , Unal Ekrem , Kose Mehmet
Published: September 2020

Type 1 plasminogen deficiency is a rare genetic disorder. Type 1 plasminogen deficiency is characterized by fibrin-rich pseudomembrane formation on mucosal surfaces, particularly the conjunctiva. Tracheobronchial tree involvement is a less common reported manifestation of type 1 plasminogen deficiency. Pseudomembranes in the tracheobronchial tree may result in respiratory compromise and ultimately fail if not recognized and treated. Currently, there is no specific replacement therapy approved for the treatment of congenital plasminogen deficiency. In the present paper, we report that type 1 plasminogen deficiency with novel frameshift mutation and pulmonary involvement was treated initially with systemic fresh frozen plasma followed by pulmonary lavage with fresh frozen plasma and tissue plasminogen activator.
A Community Emergency Department Rotation for Pediatric Emergency Medicine Fellows
Authors: Langhan Melissa L. , Woolf Seth , Tiyyagura Gunjan
Published: September 2020

Objective

There have been increasing job opportunities for pediatric emergency medicine (PEM) specialists within community emergency departments (CEDs), where 90% of children receive emergency care. The majority of training for PEM fellows occurs in academic children's hospitals, which may expose fellows to different resources than CEDs. Our goals were to develop and to evaluate a CED rotation aimed at improving exposure to this care environment for PEM fellows.

Methods

Kern's 6 steps of curriculum development served as our framework to identify the problem, conduct a needs assessment, develop goals and objectives, formulate an educational strategy, and then plan the implementation and evaluation. Discussion and buy-in among trainees and hospital leadership took place during rotation development. Informal and web-based surveys of PEM fellows and CED attendings evaluated the rotation and assessed participants' reactions, changes in knowledge, and changes in behavior.

Results

The CED rotation was piloted at 1 PEM fellowship program over 2 years. Nine PEM fellows participated in the month-long rotation. The majority of participants reported that the rotation goals and objectives were met and that they acquired new skills and rated the CED rotation as good or excellent. Challenges to the CED rotation included lower patient acuity and distance to the CED.

Conclusions

A new CED rotation was developed, piloted, and well received by participants. Given the potential differences in practice between tertiary care children's emergency departments and CEDs, as well as increasing job opportunities in CEDs, program directors should consider incorporating a CED rotation for their PEM fellows.
Patient Outcomes With Febrile Neutropenia Based on Time to Antibiotics in the Emergency Department
Authors: Dessie Almaz S. , Lanning Miranda , Nichols Tristan , Delgado Eva M. , Hart Lisa Sinclair , Agrawal Anurag K.
Published: September 2020

Objective

Although bacteremia in pediatric oncology patients with febrile neutropenia (FN) is not uncommon, sepsis and mortality are rare. Because of the lack of clinically meaningful decision tools to identify high-risk patients with bacteremia, time to antibiotic administration (TTA) is increasingly considered an important quality and safety measure in the emergency department. Because little evidence exists suggesting that this benchmark is beneficial, we sought to determine whether TTA of 60 minutes or less is associated with improved outcomes.

Methods

We retrospectively reviewed patients presenting to a pediatric emergency department with FN from November 2013 to June 2016. Clinical outcomes including mortality, pediatric intensive care unit admission, imaging, fluid resuscitation of 40 mL/kg or greater in the first 24 hours, and length of stay were compared between TTA of 60 minutes or less and more than 60 minutes.

Results

One hundred seventy-nine episodes of FN were analyzed. The median TTA was 76 minutes (interquartile range, 58–105). The incidence of bacteremia was higher in patients with TTA of more than 60 minutes (12% vs 2%, P = 0.04), but without impact on mortality, pediatric intensive care unit admission, fluid resuscitation, or median length of stay. The median TTA was not different for those who were and were not bacteremic (91 vs 73 minutes, P = 0.11).

Conclusions

Time to antibiotic administration of more than 60 minutes did not increase mortality in pediatric oncology patients with FN. Our study adds to the existing literature that TTA of 60 minutes or less does not seem to improve outcomes in pediatric FN. Further larger studies are required to confirm these findings and determine which features predispose pediatric FN patients to morbidity and mortality.
Cytoreductive Nephrectomy in Patients Presenting With Advanced Disease
Authors: Shapiro Daniel D. , Westerman Mary E. , Karam Jose A. , Wood Christopher G.
Published: September 2020

Determining the appropriate patients for cytoreductive nephrectomy (CN) has evolved with the integration of more effective systemic therapies for patients with metastatic renal cell carcinoma (mRCC). While previously considered to be first-line therapy for mRCC, CN has not demonstrated a significant survival advantage over systemic therapy in more recent randomized trials when compared with targeted therapy. Conversely, multiple observational studies demonstrate a therapeutic benefit for CN. This review synthesizes the current literature regarding patient selection for CN and further evaluates the role of CN in the current era of immune checkpoint inhibitor therapy. With careful patient selection, CN maintains an important role in the management of mRCC patients.
The Immunotherapy Revolution in Kidney Cancer Treatment
Authors: Hasanov Elshad , Gao Jianjun , Tannir Nizar M.
Published: September 2020

The recent discovery of immune checkpoint inhibitors (ICIs) has revolutionized cancer treatment, including the treatment for renal cell carcinoma (RCC). Following the eras of cytokines and molecularly targeted therapies including vascular endothelial growth factor–directed agents and mammalian target of rapamycin (mTOR) inhibitors, ICIs have become the latest addition to the RCC armamentarium. To understand the scientific rationale behind this revolution in RCC treatment, we have reviewed the fundamental discoveries underlying the transition from old (cytokines) to new (ICIs) immunotherapies. We summarize the pivotal trials (CheckMate 025, CheckMate 214, KEYNOTE-426, JAVELIN Renal 101, IMmotion151) of checkpoint inhibitors for clear cell RCC in various treatment settings. With the availability of many different combination therapies and many more currently under investigation, clear cell RCC treatment is becoming more complex. Patient preferences, disease volumes, and adverse event profiles are essential in determining which option is the best for an individual patient. In the future, biomarkers currently under development could guide these treatment decisions.
Advanced Non–Clear Cell Kidney Cancer
Authors: Ornstein Moshe C. , Hutson Thomas E.
Published: September 2020

Non–clear cell renal cell carcinoma (nccRCC) accounts for approximately 25% of RCC diagnoses. Although broadly labeled as “nccRCC,” they comprised a host of histologies that include papillary, chromophobe, unclassified, and others. Moreover, these histological variants are further subclassified on the basis of genomic profiling, thereby highlighting nccRCC to be anything but a homogenous cohort of RCC. The heterogeneity of nccRCC has proved challenging in developing therapeutics for this population. Although ccRCC therapeutic data have been commonly extrapolated for the treatment of nccRCC, the overall poor outcome of these patients highlights an unmet need. In an era of precision medicine, genomic analysis, and predictive biomarkers, novel approach to drug design and development is necessary to optimize treatment outcomes in nccRCC patients. Herein, we provide an overview of the nccRCC histologies, clinical trial data, and future opportunities for treatment options and development in nccRCC.
Economic Case for Scale-up of the WHO Surgical Safety Checklist at the National Level in Sub-Saharan Africa
Authors: White Michelle C. , Leather Andrew J. M. , Sevdalis Nick , Healey Andy
Published: September 2020

Objectives:

To evaluate the economic case for nationwide scale-up of the World Health Organization (WHO) Surgical Safety Checklist using cost-effectiveness and benefit-cost analyses.

Background:

The Checklist improves surgical outcomes but the economic case for widespread use remains uncertain. For perioperative quality improvement interventions to compete successfully against other worthwhile health and nonhealth interventions for limited government resources they must demonstrate cost-effectiveness and positive societal benefit.

Methods:

Using data from 3 countries, we estimated the benefits as the total years of life lost (YLL) due to postoperative mortality averted over a 3 year period; converted the benefits to dollar equivalent values using estimates of the economic value of an additional year of life expectancy; estimated total implementation costs; and determined incremental cost-effectiveness ratio (ICER) and benefit-cost ratio (BCR). Costs are reported in international dollars using Word Bank purchasing power parity conversion factors at 2016 price-levels.

Results:

In Benin, Cameroon, and Madagascar ICERs were: $31, $138, and $118 per additional YLL averted; and BCRs were 62, 29, and 9, respectively. Sensitivity analysis demonstrated that the associated mortality reduction and increased usage due to Checklist scale-up would need to deviate approximately 10-fold from published data to change our main interpretations.

Conclusions:

According to WHO criteria, Checklist scale-up is considered “very cost-effective” and for every $ 1 spent the potential return on investment is $9 to $62. These results compare favorably with other health and nonhealth interventions and support the economic argument for investing in Checklist scale-up as part of a national strategy for improving surgical outcomes.
MRI-Diagnosed Tumor Deposits and EMVI Status Have Superior Prognostic Accuracy to Current Clinical TNM Staging in Rectal Cancer
Authors: Lord Amy C. , D’Souza Nigel , Shaw Annabel , Rokan Zena , Moran Brendan , Abulafi Muti , Rasheed Shahnawaz , Chandramohan Anuradha , Corr Alison , Chau Ian , Brown Gina
Published: September 2020

Summary Background Data:

MRI assessment of rectal cancer not only assesses tumor depth and surgical resectability but also extramural disease which affects prognosis. We have observed that nonnodal tumor nodules (tumor deposits; mrTDs) have a distinct MRI appearance compared to lymph node metastases (mrLNMs).

Objective:

We aimed to assess whether mrTDs and mrLNMs have different prognostic implications and compare these to other known prognostic markers.

Methods:

This was a retrospective cohort study of 233 patients undergoing resection for rectal cancer from January 2007 to October 2015. Data were obtained from electronic records and MRIs blindly rereported. Survival was determined using Kaplan-Meier method. Prognostic markers were evaluated using Cox regression and competing risks analysis. Inter-observer agreement for mrTD was measured using Cohen Kappa.

Results:

On multivariable analysis, baseline mrTD/mrEMVI (extramural venous invasion) status was the only significant MRI factor for adverse survival [hazard ratio (HR) 2.36 (1.54–3.61] for overall survival, 2.37 (1.47–3.80) for disease-free survival (both P < 0.001), superseding T and N categories. mrLNMs were associated with good prognosis (HR 0.50 (0.31–0.80) P = 0.004 for overall survival, 0.60 (0.40–0.90) P = 0.014 for disease-free survival). On multivariable analysis, mrTDs/mrEMVI were strongly associated with distant recurrence (HR 6.53 (2.52–16.91) P ≤ 0.001) whereas T and N category were not. In a subgroup analysis of posttreatment MRIs in postchemoradiotherapy patients, mrTD/mrEMVI status was again the only significant prognostic factor; furthermore those who showed a good treatment response had a prognosis similar to patients who were negative at baseline. Inter-observer agreement for detection of mrTDs was k0.77 and k0.83.

Conclusions:

Current MRI staging predicting T and N status does not adequately predict prognosis. Positive mrTD/mrEMVI status has greater prognostic accuracy and would be superior in determining treatment and follow-up protocols. Chemoradiotherapy may be a highly effective treatment strategy in mrTD/mrEMVI positive patients.
Lipoprotein distribution of Apo CIII glycoforms in healthy men is linked with low TG and increased insulin sensitivity
Authors: Rodríguez Marina , Rehues Pere , Iranzo Víctor , Mora Jorge , Balsells Clara , Guardiola Montse , Ribalta Josep
Published: September 2020

Glycosylation of Apo CIII modulates its function in triglyceride metabolism, and some variants are associated with a protective or pro-atherogenic lipid profile. These associations have been studied in whole plasma Apo CIII proteoforms, but the proportion of Apo CIII proteoforms in individual lipoprotein fractions has been rarely evaluated. In the present study, we aim to measure the relative content of Apo CIII proteoforms in each lipoprotein fraction (VLDL, IDL, LDL and HDL) in a group of healthy subjects as a potential biomarker for triglyceride metabolism, cardiovascular risk and diabetes. Lipoprotein fractions were separated by differential ultracentrifugation of plasma samples. The relative concentrations of seven Apo CIII variants were measured by mass spectrometric immunoassay, and the complete lipoprotein profile was determined by NMR. The results showed high interindividual variability in the distribution of Apo CIII proteoforms across the study population but a uniform proportion in all lipoprotein fractions. Two Apo CIII variants, Apo CIII0band Apo CIII1d, were negatively correlated with plasma and VLDL triglycerides regardless of VLDL size and were associated with increased LDL size when transported in LDL particles. Apo CIII0balso showed a negative correlation with lipoprotein-insulin resistance score. Therefore, Apo CIII variants can be reliably measured in lipoprotein fractions, and our results suggest that Apo CIII0band Apo CIII1dhave a protective role in triglyceride metabolism and insulin resistance in healthy individuals.
Reciprocal connectivity of the periaqueductal gray with the ponto-medullary respiratory network in rat
Authors: Trevizan-Baú Pedro , Furuya Werner I. , Mazzone Stuart B. , Stanić Davor , Dhingra Rishi R. , Dutschmann Mathias
Published: September 2020

Synaptic activities of the periaqueductal gray (PAG) can modulate or appropriate the respiratory motor activities in the context of behavior and emotion via descending projections to nucleus retroambiguus. However, alternative anatomical pathways for the mediation of PAG-evoked respiratory modulation via core nuclei of the brainstem respiratory network remains only partially described. We injected the retrograde tracer Cholera toxin subunit B (CT-B) in the pontine Kölliker-Fuse nucleus (KFn,n=5), medullary Bötzinger (BötC,n=3) and pre-Bötzinger complexes (pre-BötC;n=3), and the caudal raphé nuclei (n=3), and quantified the ascending and descending connectivity of the PAG. CT-B injections in the KFn, pre-BötC, and caudal raphé, but not in the BötC, resulted in CT-B-labeled neurons that were predominantly located in the lateral and ventrolateral PAG columns. In turn, CT-B injections into the lateral and ventrolateral PAG columns (n=4) yield the highest numbers of CT-B-labeled neurons in the KFn and far fewer numbers of labeled neurons in the pre-BötC and caudal raphé. Analysis of the relative projection strength revealed that the KFn shares the densest reciprocal connectivity with the PAG (ventrolateral and lateral columns, in particular). Overall, our data imply that the PAG may engage a distributed respiratory rhythm and pattern generating network beyond the nucleus retroambiguus to mediate downstream modulation of breathing. However, the reciprocal connectivity of the KFn and PAG suggests specific roles for synaptic interaction between these two nuclei that are most likely related to the regulation of upper airway patency during vocalization or other volitional orofacial behaviors.

Highlights

The lateral and ventrolateral PAG project to the primary respiratory network.

The Kölliker-Fuse nucleus shares the densest reciprocal connectivity with the PAG.

The Bötzinger complex appears to have very little connectivity with the PAG.
Smad3Regulates Smooth Muscle Cell Fate and Governs Adverse Remodeling and Calcification of Atherosclerotic Plaque
Authors: Cheng Paul , Wirka Robert C. , Kim Juyong Brian , Nguyen Trieu , Kundu Ramendra , Zhao Quanyi , Pedroza Albert , Nagao Manabu , Iyer Dharini , Fischbein Michael P. , Quertermous Thomas
Published: September 2020

Atherosclerotic plaques consist mostly of smooth muscle cells (SMC), and genes that influence SMC biology can modulate coronary artery disease (CAD) risk. Allelic variation at 15q22.33 has been identified by genome-wide association studies to modify the risk of CAD, and is associated with expression ofSMAD3in SMC, but the mechanism by which this gene modifies CAD risk remains poorly understood. SMC-specific deletion ofSmad3in a murine atherosclerosis model resulted in greater plaque burden, positive remodeling, and increased vascular calcification. Single-cell transcriptomic analyses revealed that loss ofSmad3altered SMC progeny phenotype toward the previously described chondromyocyte fate, but importantly also promoted transition to a novel cell-state that governs remodeling and recruitment of inflammatory cells. This new remodeling population was marked by uniquely highMmp3andCxcl12expression, and its appearance correlated with higher-risk plaque features such as increased positive remodeling and macrophage content. Further, investigation of transcriptional mechanisms by which Smad3 alters SMC cell-fate revealed novel roles for Hox and Sox transcription factors whose direct interaction with Smad3 regulate an extensive transcriptional program balancing remodeling and vascular ECM with significant implications for human Mendelian aortic aneurysmal diseases. Together, these data suggest thatSmad3expression in SMC inhibits the emergence of specific SMC phenotypic transition cells that mediate adverse plaque features, including positive remodeling, monocyte recruitment, and vascular calcification.
Amazonian soil metagenomes indicate different physiological strategies of microbial communities in response to land use change
Authors: Khan Md Abdul Wadud , Bohannan Brendan J. M. , Meyer Kyle M. , Klein Ann M. , Nüsslein Klaus , Grover James P. , Rodrigues Jorge L. Mazza
Published: September 2020

Despite the global importance in ecological processes, the Amazon rainforest has been subjected to high rates of deforestation, mostly for pasturelands, over the last few decades. In this study, we used a combination of deep shotgun metagenomics and a machine learning approach to compare physiological strategies of microbial communities between contrasting forest and pasture soils. We showed that microbial communities (bacteria, archaea and viruses), and the composition of protein-coding genes are distinct in each ecosystem. The diversities of these metagenomic datasets are strongly correlated, indicating that the protein-coding genes found in any given sample of these soil types are predictable from their taxonomic lineages. Shifts in metagenome profiles reflected potential physiological differences caused by forest-to-pasture conversion with alterations in gene abundances related to carbohydrate and energy metabolisms. These variations in these gene contents are associated with several soil factors including C/N, temperature and H++Al3+ (exchangeable acidity). These data underscore that microbial community taxa and protein-coding genes co-vary. Differences in gene abundances for carbohydrate utilization, energy, amino acid, and xenobiotic metabolisms indicate alterations of physiological strategy with forest-to-pasture conversion, with potential consequences to C and N cycles. Our analysis also indicated that soil virome was altered and shifts in the viral community provide insights into increased health risks to human and animal populations.
Development of the Pre-Gnathal Segments of the Insect Head Indicates They Are Not Serial Homologues of Trunk Segments
Authors: Lev Oren , Chipman Ariel D.
Published: September 2020

The three anterior-most segments in arthropods contain the ganglia that make up the arthropod brain. These segments, the pre-gnathal segments, are known to exhibit many developmental differences to other segments, believed to reflect their divergent morphology. We have analyzed the expression and function of the genes involved in the segment-polarity network in the pre-gnathal segments compared with the trunk segments in the hemimetabolous insectOncopeltus fasciatus. We show that there are fundamental differences in the way the pre-gnathal segments are generated and patterned, relative to all other segments, and that these differences are general to all arthropods. We argue that given these differences, the pre-gnathal segments should not be considered serially homologous to trunk segments. This realization has important implications for our understanding of the evolution of the arthropod head. We suggest a novel scenario for arthropod head evolution that posits duplication of an ancestral single-segmented head into three descendent segments. This scenario is consistent with what we know of head evolution from the fossil record, and helps reconcile some of the debates about early arthropod evolution.
An expanded gene catalog of the mouse gut metagenome
Authors: Zhu Jiahui , Ren Huahui , Zhong Huanzi , Li Xiaoping , Zou Yuanqiang , Han Mo , Li Minli , Madsen Lise , Kristiansen Karsten , Xiao Liang
Published: September 2020

High-quality and comprehensive reference gene catalogs are essential for metagenomic research. The rather low diversity of samples used to construct existing catalogs of mouse gut metagenomes limits the size and numbers of identified genes in existing catalogs. We therefore established an expanded gene catalog of genes in the mouse gut metagenomes (EMGC) containing >5.8 million genes by integrating 88 newly sequenced samples, 86 mouse-gut-related bacterial genomes and 3 existing gene catalogs. EMGC increases the number on non-redundant genes by more than one million genes compared to the so far most extensive catalog. More than 50% of the genes in EMGC were taxonomically assigned and 30% were functionally annotated. 902 Metagenomic species (MGS) assigned to 122 taxa are identified based on the EMGC. The EMGC-based analysis of samples from groups of mice originating from different animal providers, housing laboratories and genetic strains substantiated that diet is a major contributor to differences in composition and functional potential of the gut microbiota irrespective of differences in environment and genetic background. We envisage that EMGC will serve as an efficient and resource-saving reference dataset for future metagenomic studies in mice.
Extracellular DJ-1 induces sterile inflammation in the ischemic brain
Authors: Nakamura Koutarou , Sakai Seiichiro , Tsuyama Jun , Nakamura Akari , Otani Kento , Kurabayashi Kumiko , Yogiashi Yoshiko , Masai Hisao , Shichita Takashi
Published: September 2020

Inflammation is implicated in the onset and progression of various diseases, including cerebral pathologies. Here we report that DJ-1, which plays a role within cells as an antioxidant protein, functions as a damage-associated molecular pattern (DAMP), and triggers inflammation if released from dead cells into the extracellular space. We first found that recombinant DJ-1 protein induces the production of various inflammatory cytokines in bone marrow-derived macrophages (BMMs). We further identified a unique peptide sequence in the αG and αH helices of DJ-1 that activates Toll-like receptor 2 (TLR2) and TLR4. In the ischemic brain, DJ-1 is released into the extracellular space from necrotic neurons within 24 hours after stroke onset and makes direct contact with the surfaces of infiltrating myeloid cells. Administration of an antibody against DJ-1 suppresses the expression of inflammatory cytokines in infiltrating immune cells and attenuates ischemic neuronal damage. Our results demonstrate a previously unknown function of DJ-1 as a DAMP and suggest that extracellular DJ-1 could be a therapeutic target to prevent inflammation in tissue injuries and neurodegenerative diseases.

Significance statement

DJ-1 has been thoroughly investigated as a cytoprotective antioxidant protein in neurons. However, here we demonstrate that extracellularly released DJ-1 triggers neurotoxic inflammation after ischemic stroke. Intracellular DJ-1 increases in response to oxidative stress in ischemic neurons, but if ischemic stresses result in necrotic cell death, DJ-1 is released extracellularly. Released DJ-1 interacts with TLR2 and TLR4 on the surface of infiltrating myeloid cells and triggers post-ischemic inflammation, leading to the exacerbated pathologies of ischemic stroke. Thus, extracellular DJ-1 is a previously unknown inflammatogenic DAMP, and may be a putative target for therapeutic intervention to prevent progression of inflammatory and neurodegenerative diseases.
Tissue Level Profiling of SARS-CoV-2 antivirals in mice to predict their effects: comparing Remdesivir’s active metabolite GS-441 524 vs. the clinically failed Hydroxychloroquine
Authors: Scherf-Clavel Oliver , Kaczmarek Edith , Kinzig Martina , Friedl Bettina , Feja Malte , Höhl Rainer , Nau Roland , Holzgrabe Ulrike , Gernert Manuela , Richter Franziska , Sörgel Fritz
Published: September 2020

Background and Objectives

Remdesivir and hydroxychloroquine are or were among the most promising therapeutic options to tackle the current SARS-CoV-2 pandemic. Besides the use of the prodrug remdesivir itself, the direct administration of GS-441 524, the resulting main metabolite of remdesivir, could be advantageous and even more effective. All substances were not originally developed for the treatment of COVID-19 and especially for GS-441 524 little is known about its pharmacokinetic and physical-chemical properties. To justify the application of new or repurposed drugs in humans, pre-clinical in vivo animal models are mandatory to investigate relevant PK and PD properties and their relationship to each other. In this study, an adapted mouse model was chosen to demonstrate its suitability to provide sufficient information on the model substances GS-441 524 and HCQ regarding plasma concentration and distribution into relevant tissues a prerequisite for treatment effectiveness.

Methods

GS-441 524 and HCQ were administered intravenously as a single injection to male mice. Blood and organ samples were taken at several time points and drug concentrations were quantified in plasma and tissue homogenates by two liquid chromatography/tandem mass spectrometry methods. In vitro experiments were conducted to investigate the degradation of remdesivir in human plasma and blood. All pharmacokinetic analyses were performed with R Studio using non-compartmental analysis.

Results

High tissue to plasma ratios for GS-441 524 and HCQ were found, indicating a significant distribution into the examined tissue, except for the central nervous system and fat. For GS-441 524, measured tissue concentrations exceeded the reported in vitro EC50values by more than 10-fold and in consideration of its high efficacy against feline infectious peritonitis, GS-441 524 could indeed be effective against SARS-CoV-2 in vivo. For HCQ, relatively high in vitro EC50values are reported, which were not reached in all tissues. Facing its slow tissue distribution, HCQ might not lead to sufficient tissue saturation for a reliable antiviral effect.

Conclusion

The mouse model was able to characterise the PK and tissue distribution of both model substances and is a suitable tool to investigate early drug candidates against SARS-CoV-2. Furthermore, we could demonstrate a high tissue distribution of GS-441 524 even if not administered as the prodrug remdesivir.
Lopinavir-ritonavir is not an effective inhibitor of the main protease activity of SARS-CoV-2in vitro
Authors: Jang Minsu , Park Yea-In , Park Rackhyun , Cha Yeo-Eun , Namkoong Sim , Lee Jin I. , Park Junsoo
Published: September 2020

COVID-19 has caused over 900,000 deaths worldwide as of September 2020, and effective medicines are urgently needed. Lopinavir was identified as an inhibitor of the HIV protease, and a lopinavir-ritonavir combination therapy was reported to be beneficial for the treatment of SARS and MERS. However, recent clinical tests could not prove that lopinavir-ritonavir therapy was an effective treatment for COVID-19. In this report, we examined the effect of lopinavir and ritonavir to the activity of the purified main protease (Mpro) protein of SARS- CoV-2, the causative virus of COVID-19. Unexpectedly, lopinavir and ritonavir did not inhibit Mpro activity. These results will aid the drug candidate selection for ongoing and future COVID-19 clinical trials.