The longitudinal behavioral effects of acute exposure to galactic cosmic radiation in female C57BL/6J mice: implications for deep space missions, female crews, and potential antioxidant countermeasures

Galactic cosmic radiation (GCR) is an unavoidable risk to astronauts that may affect mission success. Male rodents exposed to 33-beam-GCR (33-GCR) show short-term cognitive deficits but reports on female rodents and long-term assessment is lacking. Here we asked: What are the longitudinal behavioral effects of 33-GCR on female mice? Also, can an antioxidant/anti-inflammatory compound mitigate the impact of 33-GCR? Mature (6-month-old) C57BL/6J female mice received the antioxidant CDDO-EA (400 µg/g of food) or a control diet (vehicle, Veh) for 5 days and either Sham-irradiation (IRR) or whole-body 33-GCR (0.75Gy) on the 4th day. Three-months post-IRR, mice underwent two touchscreen-platform tests: 1) location discrimination reversal (which tests behavior pattern separation and cognitive flexibility, two abilities reliant on the dentate gyrus) and 2) stimulus-response learning/extinction. Mice then underwent arena-based behavior tests (e.g. open field, 3-chamber social interaction). At the experiment end (14.25-month post-IRR), neurogenesis was assessed (doublecortin-immunoreactive [DCX+] dentate gyrus neurons). Female mice exposed to Veh/Sham vs. Veh/33-GCR had similar pattern separation (% correct to 1st reversal). There were two effects of diet: CDDO-EA/Sham and CDDO-EA/33-GCR mice had better pattern separation vs. their respective control groups (Veh/Sham, Veh/33-GCR), and CDDO-EA/33-GCR mice had better cognitive flexibility (reversal number) vs. Veh/33-GCR mice. Notably, one radiation effect/CDDO-EA countereffect also emerged: Veh/33-GCR mice had worse stimulus-response learning (days to completion) vs. all other groups, including CDDO-EA/33-GCR mice. In general, all mice show normal anxiety-like behavior, exploration, and habituation to novel environments. There was also a change in neurogenesis: Veh/33-GCR mice had fewer DCX+ dentate gyrus immature neurons vs. Veh/Sham mice. Our study implies space radiation is a risk to a female crew's longitudinal mission-relevant cognitive processes and CDDO-EA is a potential dietary countermeasure for space-radiation CNS risks.

An Engineered Mouse Model That Generates a Diverse Repertoire of Endogenous, High-Affinity Common Light Chain Antibodies

Bispecific antibodies have gained increasing popularity as therapeutics as they enable novel activities that cannot be achieved with monospecific antibodies. Some of the most popular bispecific formats are molecules in which two Fab arms with different antigen specificities are combined into one IgG-like molecule. One way to produce these bispecific molecules requires the discovery of antibodies against the two antigens of interest that share a common light chain. Here, we present the generation and characterization of a common light chain mouse model, in which the endogenous IGKJ cluster is replaced with a prearranged, modified murine IGKV10-96/IGKJ1 segment. We demonstrate that genetic modification does not impact B-cell development. Upon immunization with ovalbumin, the animals generate an antibody repertoire with VH gene segment usage of a similar diversity to wildtype mice, while the light chain diversity is restricted to antibodies derived from the prearranged IGKV10-96/IGKJ1 germline. We further show that the clonotype diversity of the common light chain immune repertoire matches the diversity of immune repertoire isolated from wildtype mice. Finally, the common light chain anti-ovalbumin antibodies have only slightly lower affinities than antibodies isolated from wildtype mice, demonstrating the suitability of these animals for antibody discovery for bispecific antibody generation.

The Relationship between Choroidal Thickness and Liver Damage in Simple Auto-immune Hepatitis Patients

BACKGROUND

There was no sufficient clinical evidence on the relationship between auto-immune hepatitis (AIH) and risk of eye illness, except 11 uveitis cases where related AIH is reported currently.

AIM

To determine the relationship between choroidal thickness (ChT) and liver damage in simple AIH patients without ocular symptoms after oral prednisone treatment.

PATIENTS AND METHODS

This prospective observational study included simple AIH patients. The patients' ChT was measured by swept-source (SS)-optical coherence tomography (OCT), and the liver damage was evaluated by alanine aminotransferase (ALT) and aspartate aminotransferase (AST). ChT and liver functions were assessed prior to and after treatment. Then comparisons were made prior to and post treatment. The relationships between biochemical indexes of liver injury and ChT were evaluated after a mean (SD) of 24 (1.28) weeks of regular oral prednisone.

RESULTS

A total of 35 patients (31 females, aged 45.66 ± 11.62 years) were included. After treatment, ChT was significantly increased in all sectors (including the center sector, superior inner sector, inner nasal sector, inferior inner sector, inner temporal sector, superior outer sector, outer nasal sector, inferior outer sector, and outer temporal sector) (all P < 0.001). After treatment, both ALT (51.34 ± 44.16 vs 255.06 ± 107.84, P < 0.001) and AST (38.66 ± 27.12 vs 164.89 ± 85.58, P < 0.001) were significantly decreased. The increase of ChT in all sectors was significantly related to the decrease of ALT and AST (all P < 0.001).

CONCLUSION

The improvement of ChT might reflect the remission of liver damage in simple AIH patients without ocular symptoms during oral prednisone treatment.

A Free, Open-Source Toolkit to Produce 3D Bolus in the Clinic

PURPOSE/OBJECTIVE(S)

Tissue-equivalent, tissue-approximating and tissue-replacing bolus materials have been in use for decades in radiotherapy. Most frequently these materials are applied to a patient's skin to bring the highest dose region towards the surface of the skin-which is the location of the target. These materials can be applied at the time of simulation and included in a planning CT scan, or can be added during the planning process and first physically applied at the time of treatment. One of the most widely adopted materials for bolus has been sheets of a commercially available proprietary synthetic gel, which is uniform in thickness, and has some ability to match the curvature of the patient's body. Recently investigators have worked to create boluses using 3D printing technology, including several commercially available offerings. We hypothesized that we could create a bespoke, 3D bolus solution, using a series of open-source and free software products.

MATERIALS/METHODS

For an anthropomorphic phantom, a radiation treatment plan representative of skin cancer treatment was designed, this included a superficial target. The DICOM CT and structure set were imported into 3D Slicer, which is a free, open-source software for visualization, processing, segmentation, and registration. Using 3D Slicer, the bolus structure was saved as an STL file. Meshmixer, a free software for working with triangle meshes, was used to complete a mold design, and the mold parts were then printed using a rigid filament on a 3D printer. The mold parts were glued together, and small spring clamps were used secure the walls to the shells to ensure mold integrity. The mold was then filled with a thinned and degassed silicone. After appropriate curing, demolding was completed by removing the clamps and separating the walls. After QA, the bolus was applied to the anthropomorphic phantom and CTs were taken to compare a commercial sheet bolus with the in-house 3D printed product.

RESULTS

The bolus made via the in-house 3D printing process fit even complicated patient geometries well, and had both an obvious visual/goodness of fit advantage over the commercial sheet bolus and a nuanced dosimetric improvement as the air gaps present in the commercial sheet bolus were not desirable nor reproducible. The overall in-house workflow was efficient, and clinically reasonable (an estimated time of 72 hours was presented to the physician team, but in testing less than 24 hours was needed from export to delivery of the finished product).

CONCLUSION

In this work we explored whether motivated groups and departments could produce dosimetrically accurate and clinically reasonable custom boluses for patients undergoing radiotherapy to a superficial area of the body, using a test case on an anthropomorphic phantom. We found that this was absolutely achievable and could be implemented with no funds spent on software or licenses. Provided that a 3D printer, filament and silicone are available, any thoughtful practice can join the bespoke-bolus-club.

A Rare Presentation of Thoracic Intramedullary Chordoma with Adjacent Bone Involvement: A Case Report and Review of the Literature

Introduction/Objective

Chordoma originates from remnants of the embryonal notochord, and arise in bones anywhere along the spine and skull base. The most common location was thought to be the sacrum, followed by the clivus, and to a much lesser extent the rest of the spine. However, some studies have suggested an equal distribution among the skull base (32%), mobile spine (32.8%), and sacro-coccygeal bones (29.2%). Here we report a case of chordoma involving the thoracic spine. at the level of T2.

Methods/Case Report

A 63-year-old male with no significant past medical history who presented with 5-6 months of intermittent, bilateral lower extremity weakness and numbness in the trunk and lower extremities. MRI of the thoracic spine demonstrated a contrast enhancing mass at T2 vertebral level with spinal cord compression and adjacent bone destruction. T1-3 laminectomy with debulking of the tumor was performed. Microscopically, the tumor cells have a lobulated architecture and are composed of epithelioid cells arranged in cords, clusters or nests, embedded in a myxoid mucinous matrix. The epithelioid cells have a variably vacuolated cytoplasm ("physaliphorous" cells). The epithelioid cells are positive for CK AE1/3, Cam5.2, EMA and Brachyury (nuclear stain), and S100 (focal). These findings support a diagnosis of chordoma.

Results (if a Case Study enter NA)

N/A.

Conclusion

The most important and difficult differential diagnosis of chordoma is with well-differentiated chondrosarcoma. Although both chordomas and chondrosarcomas express S100, chondrosarcomas do not express cytokeratins, EMA or brachyury. Chordomas have an aggressive clinical course and poor outcome with local extension, recurrence and even metastasis. The treatment is en block surgical resection with adjuvant radiotherapy. The extent of the initial surgical resection is the most significant prognostic factor.

Sudden Cardiac Death due to Giant Cell Myocarditis in a 37-Year-Old Female: Case Report

Introduction/Objective

Giant cell myocarditis (GCM) is a rare and aggressive inflammatory process that targets the myocardium and is often rapidly fatal. Most cases have been reported in young to middle aged adults with a slight male predominance. The etiology of this disease is largely unknown, however there is an association with multiple autoimmune disorders. Most patients present with rapidly progressive or fulminant heart failure, arrhythmias, heart block or sudden cardiac death. The incidence of GCM ranges from 0.007% to 0.051% and most cases are confirmed on autopsy examination. Here we present a case of GCM in a young female diagnosed on autopsy.

Methods/Case Report

A 37-year-old female presented with shortness of breath and chest pain for a 5-day duration. She had no past medical history and was otherwise well before the onset of symptoms. On admission, she was noted to have clinical findings consistent with heart failure and progressed to cardiogenic shock with ventricular arrhythmias within hours. Despite high dose corticosteroids and other supportive therapy, the patient remained in refractory, vasodilatory shock, in cardiac standstill and eventually died. Findings on autopsy included mild ventricular hypertrophy, petechial hemorrhages through out the atria and ventricles, as well as pulmonary edema and congestion. Microscopic examination showed a diffuse infiltrating pattern of inflammation within the heart, that was composed predominantly of lymphocytes, giant cells, scattered neutrophils, and eosinophils. The lymphocytes were CD3, CD4, CD8 positive and CD20 negative, consistent with a T-cell infiltrate. Gram and GMS stains were negative for bacterial and fungal microorganisms. Focal areas of necrosis without granuloma formation are also noted ruling out sarcoidosis.

Results (if a Case Study enter NA)

NA.

Conclusion

This case demonstrates a rapid manifestation of GCM in a previously healthy individual. GCM must be considered in the differential diagnosis when a young patient presents with cardiac symptoms. Early diagnosis and initiation of targeted therapy is critical for GCM patients' survival.

Impact of COVID 19 Pandemic on Radiation Oncology Care Path Time

Purpose/Objective(s)

We seek to investigate the impact of the COVID19 pandemic on the radiation oncology care path timeline. We hypothesized that the COVID19 pandemic would result in increased time to complete the care path from simulation to start of radiation.

Materials/Methods

Care path data of patients treated at a single institution were included for 3 epochs: Pre COVID (July 2019 – March 2020), C1 [PreV] (April 2020 – Dec 2020), and C2 [PostV] (Jan 2021 – September 2021). The following tasks in the care path were evaluated: simulation start time, contours completed, physician review, plan finalization, IMRT/IMPT QA, and radiation treatment start. Time stamps of completion of tasks in the radiation treatment planning care pathway were extrapolated and used to create 9-time intervals. Demographic, tumor, and treatment characteristics were gathered to stratify patients. Patients with care path times greater than 25 days were excluded from the analysis. Numerical variables are summarized using mean and standard deviation while categorical data is summarized using counts and percentages. The ANOVA test is used to compare means in RT planning times between time epochs.

Results

A total of 3557 patients were included in the study analysis: 1095 PC, 1105 C1, and 1357 C2. There were improvements in multiple car path intervals following the start of the pandemic. Across epochs, the mean time from simulation to RT Start was 10.5 days (10.9 PC, 10.3C1, and 10.3 C2) (p =0.008). The mean time from simulation to plan finalization was 5.5 days (5.6 PC, 5.7 C1, 5.2 C2, p =0.008). The mean time for plan review to start time was 5.5 days (5.7 PC, 5.2 C1, and 5.5 C2) (p=0.010). Contour completion to radiation start time was significantly shorter after the pandemic (8.8 PC vs. 8.4 C1 vs. 8.4 C2, p =0.046). The mean time from physician review to IMRT/IMPT QA was 1.7 days (1.8 PC, 1.7 C1, 1.5 C2, p = 0.007). Physician review to RT start took a mean time of 5.5 days (5.7 PC, 5.2 C1, 5.5 C2, p = 0.010). Plan finalization to IMRT/IMPT QA took a mean time of 1.1 days (1.2 PC, 1.1 C1, 1.0 C2, p = 0.01). IMRT/QA to RT start took a mean time of 4.4 days (4.6 PC, 4.0 C1, and 4.5 C2, p =0.002). The mean time from plan finalization to RT start was 5.0 days (5.2 PC, 4.6 C1, 5.0 C2, p = 0.004). There were no significant differences in simulation to contour time (p =0.181) and physician review completion to plan finalization (p =0.223)

Conclusion

The COVID19 pandemic has been a disruptive force in the management of patients in Radiation Oncology. However, we demonstrate improved efficiency in care path completion as we entered into the pandemic. Further investigation into care path efficiency is important for provider and patient satisfaction.

Durable Immunity to Ricin Toxin Elicited by Intranasally Administered Monoclonal Antibody-Based Immune Complexes

Inhalation of ricin toxin (RT) elicits profuse inflammation and cell death within the upper and lower airways, ultimately culminating in acute respiratory distress syndrome. We previously reported that the effects of pulmonary RT exposure in mice are nullified by intranasal administration of an mAb mixture consisting of PB10, directed against ricin's enzymatic subunit (RTA), and SylH3, directed against ricin's binding subunit (RTB). We now report that delivery of PB10 and SylH3 as an RT-mAb immune complex (RIC) to mice by the intranasal or i.p. routes stimulates the rapid onset of RT-specific serum IgG that persists for months. RIC administration also induced high-titer, toxin-neutralizing Abs. Moreover, RIC-treated mice were immune to a subsequent 5 × LD₅₀ RT challenge on days 30 or 90. Intranasal RIC administration was more effective than i.p. delivery at rendering mice immune to intranasal RT exposure. Finally, we found that the onset of RT-specific serum IgG following RIC delivery was independent of FcγR engagement, as revealed through FcγR knockout mice and RICs generated with PB10/SylH3 LALA (leucine to alanine) derivatives. In conclusion, a single dose of RICs given intranasally to mice was sufficient to stimulate durable protective immunity to RT by an FcγR-independent pathway.

Molecular Characterisation, Tissue Distribution, and Expression Profiling of the Cathepsin B Gene during Ovarian Follicle Development in Geese

1. Although there is evidence that Cathepsin B (CTSB) regulates the degradation and absorption of yolk precursors during avian ovarian follicle development, nothing is known about its molecular characteristics, tissue distribution or expression profiles in goose ovarian follicular compartments.2. The intact 1023 bp coding sequence of the goose CTSB gene was obtained for the first time. It encoded a polypeptide of 340 amino acids (AA) containing two conserved functional domains (i.e., Propeptide_C1 and Peptidase_C1A_Cathpsin B) and three active amino acid residues (+108, +279, and +299). Both the nucleotide and AA sequences of goose CTSB gene showed more than 90% similarity with its respective homologs from other avian species.3. The qRT-PCR results showed that CTSB mRNA was ubiquitously expressed in all examined goose tissues, with moderate to high levels in the reproductive organs including the ovarian stroma and oviduct.4. Expression of goose CTSB mRNA in the granulosa layers increased gradually from the 2-4 mm F5 follicles but declined to relatively low levels in the F4-F1 follicles while remaining statistically unchanged in the theca layers throughout follicle development.5. High sequence similarity of goose CTSB gene to other avian species suggested functional conservation of avian CTSB genes, and its fluctuating levels in the granulosa layers may be associated with the orderly progression of goose follicle development. These data laid a foundation for further elucidating the role of CTSB in the avian ovary.

MiR-181a-5p inhibits goose granulosa cell viability by targeting SIRT1

1. Granulosa cells (GCs) are involved in folliculogenesis, follicular development, and atresia. Previous studies have shown that microRNA-181a-5p (miR-181a-5p) and sirtuin 1 (SIRT1) are involved in GC proliferation and apoptosis, and SIRT1 has been predicted as one target of miR-181a-5p. However, there are few studies with poultry.2. Quantitative real-time PCR (qRT-PCR) was used to detect the expression level of miR-181a-5p in granulosa layers during geese ovarian follicular development. A methyl thiazolyl tetrazolium (MTT) assay was performed to assess the viability of geese granulosa cells treated with miR-181a-5p mimic or inhibitor. The binding sites between the SIRT1 3'-UTR region and miR-181a-5p were evaluated using a luciferase reporter assay system. SIRT1 mRNA levels were detected using qRT-PCR after transfection with miR-181a-5p mimic and inhibitor.3. The miR-181a-5p suppressed geese GC viability and regulated the mRNA expression of viability-related genes in geese GCs. SIRT1 was a target gene of miR-181a-5p and miR-181a-5p suppressed its mRNA expression.4. The miR-181a-5p may target and inhibit SIRT1 expression, thus suppressing GC viability by regulating viability-related key genes.

Leveraging Existing Institutional Resources to Maintain Quality Assurance Practices in Anatomic Pathology in the Era of Social Distancing

Introduction/Objective

Due to the COVID-19 pandemic, hospitals had to adapt practices to incorporate social distancing while maintaining quality assurance (QA) in anatomic pathology (AP). Prior to this, our general surgical pathology (SP) and cytopathology (CP) services held daily consensus conferences (CC) at a multi-headed microscope. Implementing social distancing meant only a few faculty were present onsite and avoidance of interactions at the multi-headed scope. In an effort to preserve QA through CC, faculty exploited the use of web conferencing through our HIPAA-compliant Zoom. We describe the utility of this new practice.

Methods

From 3/25-4/30/20, all SP and CP cases selected for CC were presented by respective pathologists (n=8) in their own offices by using individual microscopes with cameras, image acquisition software, and screen-sharing through Zoom. One pathologist was responsible for sending out a new CC Zoom link daily and recording the consensus diagnosis. All onsite pathologists and those at home participated.

Results

We presented 95 SP and 31 CP cases through Zoom compared to 300 SP and 60 CP cases presented at a similar timeframe prior to social distancing. This 68% and 48% decline could be attributed to elective procedure cancellation. We assigned a consensus diagnosis to all cases, with 77% overall being malignant diagnoses, and breast being the most common SP specimen type (22%). Additionally, all participating pathologists felt comfortable with the new format irrespective of being onsite or at home. Apart from minor audio issues, we did not notice significant lag time or visual disturbances that interfered with diagnostic abilities. Importantly, the transition did not involve investing in new technology.

Conclusion

The new virtual CC allowed our department to maintain QA practices in AP without sacrificing quality and serves as a starting point to investigating the use of this technology to other applications in AP, such as overnight frozen sections.

A Humanized Monoclonal Antibody Cocktail to Prevent Pulmonary Ricin Intoxication

PB10 IgG₁, a monoclonal antibody (MAb) directed against an immunodominant epitope on the enzymatic subunit (RTA) of ricin toxin (RT), has been shown to passively protect mice and non-human primates from an aerosolized lethal-dose RT challenge. However, it was recently demonstrated that the therapeutic efficacy of PB10 IgG1 is significantly improved when co-administered with a second MAb, SylH3, targeting RT's binding subunit (RTB). Here we report that the PB10/SylH3 cocktail is also superior to PB10 alone when used as a pre-exposure prophylactic (PrEP) in a mouse model of intranasal RT challenge. The benefit of the PB10/SylH3 cocktail prompted us to engineer a humanized IgG1 version of SylH3 (huSylH3). The huPB10/huSylH3 cocktail proved highly efficacious in the mouse model, thereby opening the door to future testing in non-human primates.

Dopamine activates NF-κB and primes the NLRP3 inflammasome in primary human macrophages

Induction of innate immune genes in the brain is thought to be a major factor in the development of addiction to substances of abuse. As the major component of the innate immune system in the brain, aberrant activation of myeloid cells such as macrophages and microglia due to substance use may mediate neuroinflammation and contribute to the development of addiction. All addictive drugs modulate the dopaminergic system and our previous studies have identified dopamine as a pro-inflammatory modulator of macrophage function. However, the mechanism that mediates this effect is currently unknown. Inflammatory activation of macrophages and induction of cytokine production is often mediated by the transcription factor NF-κB, and prior studies have shown that dopamine can modulate NF-κB activity in T-cells and other non-immune cell lines. Here we demonstrated that dopamine can activate NF-κB in primary human macrophages, resulting in the induction of its downstream targets including the NLRP3 inflammasome and the inflammatory cytokine IL-1β. These data also indicate that dopamine primes but does not activate the NLRP3 inflammasome in human macrophages. Activation of NF-κB was required for dopamine-mediated increases in IL-1β, as an inhibitor of NF-κB was able to abrogate the effects of dopamine on production of these cytokines. Connecting an increase in extracellular dopamine to NF-κB activation and inflammation suggests specific intracellular targets that could be used to ameliorate the inflammatory impact of dopamine in neuroinflammatory conditions associated with myeloid cell activation such as addiction.

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Dopamine exposure primes, but does not activate the NLRP3 inflammasome.

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Inflammasome priming can be mediated, at least partially, by a dopamine-induced increase in the activation and nuclear translocation of NF-κB in primary human macrophages.

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Dopamine additively increases the impact of cytomegalovirus on NF-κB activation in macrophages.

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Dopamine priming increases IL-1β release in response to inflammasome activation.

An intranasally administered monoclonal antibody cocktail abrogates ricin toxin-induced pulmonary tissue damage and inflammation

Ricin toxin, a plant-derived, mannosylated glycoprotein, elicits an incapacitating and potentially lethal inflammatory response in the airways following inhalation. Uptake of ricin by alveolar macrophages (AM) and other pulmonary cell types occurs via two parallel pathways: one mediated by ricin's B subunit (RTB), a galactose-specific lectin, and one mediated by the mannose receptor (MR;CD206). Ricin's A subunit (RTA) is a ribosome-inactivating protein that triggers apoptosis in mammalian cells. It was recently reported that a single monoclonal antibody (MAb), PB10, directed against an immunodominant epitope on RTA and administered intravenously, was able to rescue Rhesus macaques from lethal aerosol dose of ricin. In this study, we now demonstrate in mice that the effectiveness PB10 is significantly improved when combined with a second MAb, SylH3, against RTB. Mice treated with PB10 alone survived lethal-dose intranasal ricin challenge, but experienced significant weight loss, moderate pulmonary inflammation (e.g., elevated IL-1 and IL-6 levels, PMN influx), and apoptosis of lung macrophages. In contrast, mice treated with the PB10/SylH3 cocktail were essentially impervious to pulmonary ricin toxin exposure, as evidenced by no weight loss, no change in local IL-1 and IL-6 levels, retention of lung macrophages, and a significant dampening of PMN recruitment into the bronchoalveolar lavage (BAL) fluids. The PB10/SylH3 cocktail only marginally reduced ricin binding to target cells in the BAL, suggesting that the antibody mixture neutralizes ricin by interfering with one or more steps in the RTB- and MR-dependent uptake pathways.

[Evaluating the level of occupational stress and its influence factors among traffic police in a district in Shanghai]

Objective: To investigate the high occupational stress and its influencing factors in traffic police in Shanghai. Methods: 728 traffic police were selected as the study subjects, and the《Occupational Health Questionnaire》was used to investigate and evaluate their job demand-control (JDC) and effort-reward imbalance model (ERI) occupational stress situation respectively. The related influencing factors were analyzed. Results: The prevalence rates of high occupational stress in JDC and ERI models were 74.6% (543/728) and 51.5% (375/728) . The influencing factors of JDC were education, marriage, average weekly hours (χ(2)=16.82, 10.04, 18.71, P<0.05) , and The influencing factors of ERI were gender, age, marriage, real monthly income level, education, work experience, and average weekly hours (χ(2)=7.02, 26.18, 6.73, 50.42, 4.75, 26.61, 112.98, 6.19, P<0.05) . The JDC multivariate logistic analysis indicated that the risk of occupational stress of married police was 2.81 times as high as that of Unmarried ones. The risk of occupational stress of traffic police with more education was 1.92 times as high as that of low eduacation, average weekly working 41-50 hours and≥51 hours was 2.53, 3.12 times as high as that of ones with average working 40 hours, respectivly. Meanwhile, the ERI multivariate logistic analysis indicated that high income level is the protective factor of occupational stress. The traffic police with 15-<20 working years were more likely to occur higher occupational stress. The traffic police with the more average weekly hours had greater possibility of higher occupational stress. Conclusion: The main influencing factors of JDC and ERI are marriage, real monthly income level, education, work experience, and average weekly hours.

An Intranasally Administered Antibody Cocktail Prevents Ricin Toxin-Induced Lung Inflammation and Alveolar Macrophage Death

Ricin toxin, a plant-derived, mannosylated glycoprotein, elicits an incapacitating and potentially lethal, pulmonary inflammatory response in the airways following inhalation. Uptake by alveolar macrophages (AM) and other pulmonary cell types occurs via ricin’s B subunit (RTB), a galactose-specific lectin, and the mannose receptor (MR; CD206). Ricin’s A subunit (RTA) is a ribosome-inactivating protein capable of inducing apoptosis in all mammalian cell types. It was recently reported that a single monoclonal antibody (MAb), PB10, directed against an immunodominant epitope on RTA, is able rescue Rhesus macaques against lethal dose of ricin administered by aerosol. In this study, we now demonstrate in mice that the effectiveness PB10 is significantly improved when combined with a second MAb, SylH3, against RTB. Mice treated with PB10 alone survived lethal-dose intranasal ricin challenge, but experienced significant weight loss, moderate pulmonary inflammation (e.g., elevated IL-1 and IL-6 levels, PMN influx), and apoptosis of alveolar and tissue macrophages. In contrast, mice treated with the PB10/SylH3 cocktail were essentially impervious to pulmonary ricin toxin exposure, as evidenced by no weight loss, no change in local IL-1 and IL-6 levels, retention of alveolar and tissue macrophage numbers, and a significant dampening of PMN recruitment to the bronchoalveolar lavage (BAL) fluids. The PB10/SylH3 cocktail only marginally reduced ricin binding to target cells in the BAL, suggesting that the antibody mixture neutralizes ricin by interfering with one or more steps in the RTB- and MR-dependent uptake pathways.

Rescue of rhesus macaques from the lethality of aerosolized ricin toxin

Ricin toxin (RT) ranks at the top of the list of bioweapons of concern to civilian and military personnel alike, due to its high potential for morbidity and mortality after inhalation. In nonhuman primates, aerosolized ricin triggers severe acute respiratory distress characterized by perivascular and alveolar edema, neutrophilic infiltration, and severe necrotizing bronchiolitis and alveolitis. There are currently no approved countermeasures for ricin intoxication. Here, we report the therapeutic potential of a humanized mAb against an immunodominant epitope on ricin's enzymatic A chain (RTA). Rhesus macaques that received i.v. huPB10 4 hours after a lethal dose of ricin aerosol exposure survived toxin challenge, whereas control animals succumbed to ricin intoxication within 30 hours. Antibody intervention at 12 hours resulted in the survival of 1 of 5 monkeys. Changes in proinflammatory cytokine, chemokine, and growth factor profiles in bronchial alveolar lavage fluids before and after toxin challenge successfully clustered animals by treatment group and survival, indicating a relationship between local tissue damage and experimental outcome. This study represents the first demonstration, to our knowledge, in nonhuman primates that the lethal effects of inhalational ricin exposure can be negated by a drug candidate, and it opens up a path forward for product development.

Fine-Specificity Epitope Analysis Identifies Contact Points on Ricin Toxin Recognized by Protective Monoclonal Antibodies

Ricin is a fast-acting protein toxin classified by the Centers for Disease Control and Prevention as a biothreat agent. In this report, we describe five new mouse mAbs directed against an immunodominant region, so-called epitope cluster II, on the surface of ricin's ribosome-inactivating enzymatic subunit A (RTA). The five mAbs were tested alongside four previously described cluster II-specific mAbs for their capacity to passively protect mice against 10× LD₅₀ ricin challenge by injection. Only three of the mAbs (LE4, PH12, and TB12) afforded protection over the 7-d study period. Neither binding affinity nor in vitro toxin-neutralizing activity could fully account for LE4, PH12, and TB12's potent in vivo activity relative to the other six mAbs. However, epitope mapping studies by hydrogen exchange-mass spectrometry revealed that LE4, PH12, and TB12 shared common contact points on RTA corresponding to RTA α-helices D and E and β-strands d and e located on the back side of RTA relative to the active site. The other six mAbs recognized overlapping epitopes on RTA, but none shared the same hydrogen exchange-mass spectrometry profile as LE4, PH12, and TB12. A high-density competition ELISA with a panel of ricin-specific, single-domain camelid Abs indicated that even though LE4, PH12, and TB12 make contact with similar secondary motifs, they likely approach RTA from different angles. These results underscore how subtle differences in epitope specificity can significantly impact Ab functionality in vivo. ImmunoHorizons, 2018, 2: 262-273.

Contribution of an unusual CDR2 element of a single domain antibody in ricin toxin binding affinity and neutralizing activity

Ricin toxin's enzymatic subunit (RTA) has been subjected to intensive B cell epitope mapping studies using a combination of competition ELISAs, hydrogen exchange-mass spectrometry and X-ray crystallography. Those studies identified four spatially distinct clusters (I-IV) of toxin-neutralizing epitopes on the surface of RTA. Here we describe A9, a new single domain camelid antibody (VHH) that was proposed to recognize a novel epitope on RTA that straddles clusters I and III. The X-ray crystal structure of A9 bound to RTA (2.6 Å resolution) revealed extensive antibody contact with RTA's β-strand h (732 Å2 buried surface area; BSA), along with limited engagement with α-helix D (90 Å2) and α-helix C (138 Å2). Collectively, these contacts explain the overlap between epitope clusters I and III, as identified by competition ELISA. However, considerable binding affinity, and, consequently, toxin-neutralizing activity of A9 is mediated by an unusual CDR2 containing five consecutive Gly residues that interact with α-helix B (82 Å2), a known neutralizing hotspot on RTA. Removal of a single Gly residue from the penta-glycine stretch in CDR2 reduced A9's binding affinity by 10-fold and eliminated toxin-neutralizing activity. Computational modeling indicates that removal of a Gly from CDR2 does not perturb contact with RTA per se, but results in the loss of an intramolecular hydrogen bond network involved in stabilizing CDR2 in the unbound state. These results reveal a novel configuration of a CDR2 element involved in neutralizing ricin toxin.

Comprehensive review and annotation of susceptibility SNPs associated with obesity-related traits

We aimed to summarize the results of genetic association studies for obesity and provide a comprehensive annotation of all susceptibility single nucleotide polymorphisms (SNPs). A total of 72 studies were summarized, resulting in 90,361 susceptibility SNPs (738 index SNPs and 89,623 linkage disequilibrium SNPs). Over 90% of the susceptibility SNPs are located in non-coding regions, and it is challenging to understand their functional significance. Therefore, we annotated these SNPs by using various functional databases. We identified 24,623 functional SNPs, including 4 nonsense SNPs, 479 missense SNPs, 399 untranslated region SNPs which might affect microRNA binding, 262 promoter and 5,492 enhancer SNPs which might affect transcription factor binding, 7 splicing sites, 76 SNPs which might affect gene methylation levels, 1,839 SNPs under natural selection and 17,351 SNPs which might modify histone binding. Expression quantitative trait loci analyses for functional SNPs identified 98 target genes, including 69 protein coding genes, 27 long non-coding RNAs and 3 processed transcripts. The percentage of protein coding genes that could be correlated with obesity-related pathways directly or through gene-gene interaction is 75.36 (52/69). Our results may serve as an encyclopaedia of obesity susceptibility SNPs and offer guide for functional experiments.

Post hoc support vector machine learning for impedimetric biosensors based on weak protein–ligand interactions

We develop a simple, open source machine learning algorithm for analyzing impedimetric biosensor data using a mobile phone.

High-Resolution Epitope Positioning of a Large Collection of Neutralizing and Nonneutralizing Single-Domain Antibodies on the Enzymatic and Binding Subunits of Ricin Toxin

We previously produced a heavy-chain-only antibody (Ab) VH domain (VHH)-displayed phage library from two alpacas that had been immunized with ricin toxoid and nontoxic mixtures of the enzymatic ricin toxin A subunit (RTA) and binding ricin toxin B subunit (RTB) (D. J. Vance, J. M. Tremblay, N. J. Mantis, and C. B. Shoemaker, J Biol Chem 288:36538-36547, 2013, https://doi.org/10.1074/jbc.M113.519207). Initial and subsequent screens of that library by direct enzyme-linked immunosorbent assay (ELISA) yielded more than two dozen unique RTA- and RTB-specific VHHs, including 10 whose structures were subsequently solved in complex with RTA. To generate a more complete antigenic map of ricin toxin and to define the epitopes associated with toxin-neutralizing activity, we subjected the VHH-displayed phage library to additional "pannings" on both receptor-bound ricin and antibody-captured ricin. We now report the full-length DNA sequences, binding affinities, and neutralizing activities of 68 unique VHHs: 31 against RTA, 33 against RTB, and 4 against ricin holotoxin. Epitope positioning was achieved through cross-competition ELISAs performed with a panel of monoclonal antibodies (MAbs) and verified, in some instances, with hydrogen-deuterium exchange mass spectrometry. The 68 VHHs grouped into more than 20 different competition bins. The RTA-specific VHHs with strong toxin-neutralizing activities were confined to bins that overlapped two previously identified neutralizing hot spots, termed clusters I and II. The four RTB-specific VHHs with potent toxin-neutralizing activity grouped within three adjacent bins situated at the RTA-RTB interface near cluster II. These results provide important insights into epitope interrelationships on the surface of ricin and delineate regions of vulnerability that can be exploited for the purpose of vaccine and therapeutic development.

Gene expression profiles indicate tissue-specific obesity regulation changes and strong obesity relevant tissues

BACKGROUND

With the growing evidence that other tissues, apart from adipose, could have strong relevance to obesity, it is necessary to comprehensively understand the relationship between obesity and other tissues, and to point out the most relevant tissues.

METHODS

There were 549 participants with 20 different tissue types involved in this study. We firstly employed both Spearman's correlation test and WGCNA (weighted correlation network analysis) to identify body mass index (BMI)-related genes. Subsequently, we performed enrichment analyses with obesity genes and pathways to see the different regulation patterns among tissues. In addition, we compared obesity genes identified by genome-wide association studies (GWAS) with BMI-related genes to find the overlapping proportion in each tissue. Finally, we integrated preceding results to identify six strong obesity relevant tissues and indicate three categories to represent different obesity relevant tissues.

RESULTS

Statistical analyses revealed diverse BMI-related genes and tissue-specific enrichment patterns among tissues. Comparison between BMI-related genes and GWAS findings showed tissue-specific expression changes of GWAS genes. Ultimately, six tissues that showed predominant performance in enrichment analyses and significantly embraced GWAS genes were referred to as strong obesity relevant tissues, including adipose, esophagus, nerve, pancreas, pituitary and skin. We also proposed three categories to represent different obesity relevant tissues.

CONCLUSIONS

We performed the first study to investigate the BMI-related gene expression changes across 20 tissues at the same time. With valid data analyses and comparison with GWAS findings, our study provides a holistic view of how different tissues correlate with obesity, and proposes target tissues for obesity pathogenesis investigation.

Highly photostable wide-dynamic-range pH sensitive semiconducting polymer dots enabled by dendronizing the near-IR emitters

One constraint of semiconducting polymer dots (Pdots), especially those with near-IR emission, is their low effective emitter ratio (∼1.5 mole percent), which limits their pH sensing performance. The other critical issue of existing Pdot-based pH sensors is their poor photostability. To address these issues, we developed a series of Pdots by dendronizing the squaraine-based pH responsive near-IR emitter, which is covalently incorporated into the polyfluorene (PFO) backbone. The fluorescence self-quenching of the NIR squaraine emitter was effectively suppressed at a high emitter concentration of 5 mole percent. Through controlling the individually incomplete energy transfer from the amorphous PFO donor to the blue β-phase PFO and NIR squaraine emitter, we obtained a ratiometric pH sensor with simultaneously improved pH sensitivity, brightness, and photostability. The Pdots showed a fast and reversible pH response over the whole biological pH range of 4.7 to 8.5. Intracellular pH mapping was successfully demonstrated using this ultra-bright and photostable Pdot-based pH indicator.

Suppression of adipocyte differentiation and lipid accumulation by stearidonic acid (SDA) in 3T3-L1 cells

Background

Increased consumption of omega-3 (ω-3) fatty acids found in cold-water fish and fish oil has been reported to protect against obesity. A potential mechanism may be through reduction in adipocyte differentiation. Stearidonic acid (SDA), a plant-based ω-3 fatty acid, has been targeted as a potential surrogate for fish-based fatty acids; however, its role in adipocyte differentiation is unknown. This study was designed to evaluate the effects of SDA on adipocyte differentiation in 3T3-L1 cells.

Methods

3T3-L1 preadipocytes were differentiated in the presence of SDA or vehicle-control. Cell viability assay was conducted to determine potential toxicity of SDA. Lipid accumulation was measured by Oil Red O staining and triglyceride (TG) quantification in differentiated 3T3-L1 adipocytes. Adipocyte differentiation was evaluated by adipogenic transcription factors and lipid accumulation gene expression by quantitative real-time polymerase chain reaction (qRT-PCR). Fatty acid analysis was conducted by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS).

Results

3T3-L1 cells treated with SDA were viable at concentrations used for all studies. SDA treatment reduced lipid accumulation in 3T3-L1 adipocytes. This anti-adipogenic effect by SDA was a result of down-regulation of mRNA levels of the adipogenic transcription factors CCAAT/enhancer-binding proteins alpha and beta (C/EBPα, C/EBPβ), peroxisome proliferator-activated receptor gamma (PPARγ), and sterol-regulatory element binding protein-1c (SREBP-1c). SDA treatment resulted in decreased expression of the lipid accumulation genes adipocyte fatty-acid binding protein (AP2), fatty acid synthase (FAS), stearoyl-CoA desaturase (SCD-1), lipoprotein lipase (LPL), glucose transporter 4 (GLUT4) and phosphoenolpyruvate carboxykinase (PEPCK). The transcriptional activity of PPARγ was found to be decreased with SDA treatment. SDA treatment led to significant EPA enrichment in 3T3-L1 adipocytes compared to vehicle-control.

Conclusion

These results demonstrated that SDA can suppress adipocyte differentiation and lipid accumulation in 3T3-L1 cells through down-regulation of adipogenic transcription factors and genes associated with lipid accumulation. This study suggests the use of SDA as a dietary treatment for obesity.

Electronic supplementary material

The online version of this article (10.1186/s12944-017-0574-7) contains supplementary material, which is available to authorized users.

Using homology modeling to interrogate binding affinity in neutralization of ricin toxin by a family of single domain antibodies

In this report we investigated, within a group of closely related single domain camelid antibodies (V_H Hs), the relationship between binding affinity and neutralizing activity as it pertains to ricin, a fast-acting toxin and biothreat agent. The V1C7-like V_H Hs (V1C7, V2B9, V2E8, and V5C1) are similar in amino acid sequence, but differ in their binding affinities and toxin-neutralizing activities. Using the X-ray crystal structure of V1C7 in complex with ricin's enzymatic subunit (RTA) as a template, Rosetta-based homology modeling coupled with energetic decomposition led us to predict that a single pairwise interaction between Arg29 on V5C1 and Glu67 on RTA was responsible for the difference in ricin toxin binding affinity between V1C7, a weak neutralizer, and V5C1, a moderate neutralizer. This prediction was borne out experimentally: substitution of Arg for Gly at position 29 enhanced V1C7's binding affinity for ricin, whereas the reverse (ie, Gly for Arg at position 29) diminished V5C1's binding affinity by >10 fold. As expected, the V5C1_R29G mutant was largely devoid of toxin-neutralizing activity (TNA). However, the TNA of the V1C7_G29R mutant was not correspondingly improved, indicating that in the V1C7 family binding affinity alone does not account for differences in antibody function. V1C7 and V5C1, as well as their respective point mutants, recognized indistinguishable epitopes on RTA, at least at the level of sensitivity afforded by hydrogen-deuterium mass spectrometry. The results of this study have implications for engineering therapeutic antibodies because they demonstrate that even subtle differences in epitope specificity can account for important differences in antibody function.

Spatial location of neutralizing and non-neutralizing B cell epitopes on domain 1 of ricin toxin's binding subunit

Ricin toxin’s binding subunit (RTB) is a galactose-/N-acetylgalactosamine (Gal/GalNac)-specific lectin that mediates uptake and intracellular trafficking of ricin within mammalian cells. Structurally, RTB consists of two globular domains, each divided into three homologous sub-domains (α, β, γ). In this report, we describe five new murine IgG monoclonal antibodies (mAbs) against RTB: MH3, 8A1, 8B3, LF1, and LC5. The mAbs have similar binding affinities (K_D) for ricin holotoxin, but displayed a wide range of in vitro toxin-neutralizing activities. Competition ELISAs indicate that the two most potent toxin-neutralizing mAbs (MH3, 8A1), as well as one of the moderate toxin-neutralizing mAbs (LF1), recognize distinct epitopes near the low affinity Gal recognition domain in RTB subdomain 1α. Evaluated in a mouse model of systemic ricin challenge, all five mAbs afforded some benefit against intoxication, but only MH3 was protective. However, neither MH3 nor 24B11, another well-characterized mAb against RTB subdomain 1α, could passively protect mice against a mucosal (intranasal) ricin challenge. This is in contrast to SylH3, a previously characterized mAb directed against an epitope near RTB’s high affinity Gal/GalNac recognition element in sub-domain 2γ, which protected animals against systemic and mucosal ricin exposure. SylH3 was significantly more effective than MH3 and 24B11 at blocking ricin attachment to host cell receptors, suggesting that mucosal immunity to ricin is best imparted by antibodies that target RTB’s high affinity Gal/GalNac recognition element in subdomain 2γ, not the low affinity Gal recognition domain in subdomain 1α.

Structural Analysis of Single Domain Antibodies Bound to a Second Neutralizing Hot Spot on Ricin Toxin's Enzymatic Subunit

Ricin toxin is a heterodimer consisting of RTA, a ribosome-inactivating protein, and RTB, a lectin that facilitates receptor-mediated uptake into mammalian cells. In previous studies, we demonstrated that toxin-neutralizing antibodies target four spatially distinct hot spots on RTA, which we refer to as epitope clusters I-IV. In this report, we identified and characterized three single domain camelid antibodies (VHH) against cluster II. One of these VHHs, V5E1, ranks as one of the most potent ricin-neutralizing antibodies described to date. We solved the X-ray crystal structures of each of the three VHHs (E1, V1C7, and V5E1) in complex with RTA. V5E1 buries a total of 1,133 Å2 of surface area on RTA and makes primary contacts with α-helix A (residues 18-32), α-helix F (182-194), as well as the F-G loop. V5E1, by virtue of complementarity determining region 3 (CDR3), may also engage with RTB and potentially interfere with the high affinity galactose-recognition element that plays a critical role in toxin attachment to cell surfaces and intracellular trafficking. The two other VHHs, E1 and V1C7, bind epitopes adjacent to V5E1 but display only weak toxin neutralizing activity, thereby providing structural insights into specific residues within cluster II that may be critical contact points for toxin inactivation.

[Effect of Gas6 in silica-induced inflammation on differentiated human acute monocytic leukemia (THP-1) macrophages]

Objective: To investigate the modulation role of Gas6 in silica-induced inflammatory effect on human macrophages. Methods: Differentiated THP-1 macrophages were exposed to different concentrations of silica for 6 h and 24 h. Additionally, silica-activated macrophages were treated with different concentrations of recombine human Gas6 and Gas6 antibody respectively. Cell viabilities were determined by CCK-8 kit. Expression levels of Gas6 and inflammatory cytokines (TNF-α, IL-1β and IL-6) were measured by ELISA assay kits. Results: Silica particles induced clear dose-dependent decreases of cell viability and Gas6 expression at both 6 h and 24 h. The cell viability of 24 h is lower than 6 h at the same concentration of silica (P<0.05). Furthermore, silica activated macrophages treated with Gas6 antibody induced significant decreases of Gas6 both at 6 h and 24 h (P<0.05). After pretreated with various concentrations of Gas6 antibody, silica induced higher expressions of inflammatory cytokines (TNF-α, IL-1β, IL-6) in dose-dependent manners at two time points. Addition of exoge-nous Gas6 significantly suppressed silica-induced inflammatory cytokines concentrations mentioned above in the cell culture supernatants in clear dose-dependent manners. Conclusion: Exogenous Gas6 could inhibit the secre-tion of inflammatory cytokines in macrophages, while the block of Gas6 might enhance this inflammation.

Structural analysis of nested neutralizing and non-neutralizing B cell epitopes on ricin toxin's enzymatic subunit

In this report, we describe the X-ray crystal structures of two single domain camelid antibodies (VH H), F5 and F8, each in complex with ricin toxin's enzymatic subunit (RTA). F5 has potent toxin-neutralizing activity, while F8 has weak neutralizing activity. F5 buried a total of 1760 Å(2) in complex with RTA and made contact with three prominent secondary structural elements: α-helix B (Residues 98-106), β-strand h (Residues 113-117), and the C-terminus of α-helix D (Residues 154-156). F8 buried 1103 Å(2) in complex with RTA that was centered primarily on β-strand h. As such, the structural epitope of F8 is essentially nested within that of F5. All three of the F5 complementarity determining regions CDRs were involved in RTA contact, whereas F8 interactions were almost entirely mediated by CDR3, which essentially formed a seventh β-strand within RTA's centrally located β-sheet. A comparison of the two structures reported here to several previously reported (RTA-VH H) structures identifies putative contact sites on RTA, particularly α-helix B, associated with potent toxin-neutralizing activity. This information has implications for rational design of RTA-based subunit vaccines for biodefense. Proteins 2016; 84:1162-1172. © 2016 Wiley Periodicals, Inc.

Enhancement of humoral immunity by the type II heat-labile enterotoxin LT-IIb is dependent upon IL-6 and neutrophils

LT-IIb, a type II heat-labile enterotoxin produced by Escherichia coli, is a potent intradermal adjuvant that enhances immune responses to coadministered antigens. Although the immune mechanisms that promote this augmented immune response have not been well defined, prior intradermal immunization experiments suggested that early cellular and immunomodulatory events at the site of immunization modulated the augmentation of antigen-specific immune responses by LT-IIb. To investigate that hypothesis, mice were intradermally immunized with a recombinant ricin vaccine, a prospective toxin subunit antigen, in the presence and absence of LT-IIb. Analysis of tissue-fluid collection, coupled with histologic sections from the site of intradermal immunization, revealed that a single dose of LT-IIb induced local production of interleukin 6 and promoted a regional infiltration of neutrophils. The adjuvant effects of LT-IIb were abrogated in interleukin 6-deficient mice and when mice were depleted of neutrophils by pretreatment with anti-Ly6G. Overall, these data firmly demonstrated that LT-IIb, when used as an intradermal adjuvant, recruits neutrophils and is a potent rapid inducer of interleukin 6.