The RsfSR two-component system regulates SigF function by monitoring the state of the respiratory electron transport chain in Mycobacterium smegmatis

In Mycobacterium smegmatis, the transcriptional activity of the alternative sigma factor SigF is posttranslationally regulated by the partner switching system consisting of SigF, the anti-SigF RsbW1, and three anti-SigF antagonists (RsfA, RsfB, and RsbW3). We previously demonstrated that expression of the SigF regulon is strongly induced in the Δaa3 mutant of M. smegmatis lacking the aa3 cytochrome c oxidase, the major terminal oxidase in the respiratory electron transport chain. Here, we identified and characterized the RsfSR two-component system involved in regulating the phosphorylation state of the major anti-SigF antagonist RsfB. RsfS (MSMEG_6130) is a histidine kinase with the cyclase/histidine kinase-associated sensing extracellular 3 domain at its N terminus, and RsfR (MSMEG_6131) is a receiver domain-containing protein phosphatase 2C-type phosphatase that can dephosphorylate phosphorylated RsfB. We demonstrated that phosphorylation of RsfR on Asp74 by RsfS reduces the phosphatase activity of RsfR toward phosphorylated RsfB and that the cellular abundance of the active unphosphorylated RsfB is increased in the Δaa3 mutant relative to the WT strain. We also demonstrated that the RsfSR two-component system is required for induction of the SigF regulon under respiration-inhibitory conditions such as inactivation of the cytochrome bcc1 complex and aa3 cytochrome c oxidase, as well as hypoxia, electron donor-limiting, high ionic strength, and low pH conditions. Collectively, our results reveal a key regulatory element involved in regulating the SigF signaling system by monitoring the state of the respiratory electron transport chain.

A multi-layered network model identifies Akt1 as a common modulator of neurodegeneration

The accumulation of misfolded and aggregated proteins is a hallmark of neurodegenerative proteinopathies. Although multiple genetic loci have been associated with specific neurodegenerative diseases (NDs), molecular mechanisms that may have a broader relevance for most or all proteinopathies remain poorly resolved. In this study, we developed a multi-layered network expansion (MLnet) model to predict protein modifiers that are common to a group of diseases and, therefore, may have broader pathophysiological relevance for that group. When applied to the four NDs Alzheimer's disease (AD), Huntington's disease, and spinocerebellar ataxia types 1 and 3, we predicted multiple members of the insulin pathway, including PDK1, Akt1, InR, and sgg (GSK-3β), as common modifiers. We validated these modifiers with the help of four Drosophila ND models. Further evaluation of Akt1 in human cell-based ND models revealed that activation of Akt1 signaling by the small molecule SC79 increased cell viability in all models. Moreover, treatment of AD model mice with SC79 enhanced their long-term memory and ameliorated dysregulated anxiety levels, which are commonly affected in AD patients. These findings validate MLnet as a valuable tool to uncover molecular pathways and proteins involved in the pathophysiology of entire disease groups and identify potential therapeutic targets that have relevance across disease boundaries. MLnet can be used for any group of diseases and is available as a web tool at http://ssbio.cau.ac.kr/software/mlnet.

An analysis of contributing factors of head and neck space infections of odontogenic origin: A long-term retrospective clinical study (including COVID-19 pandemic period)

BACKGROUND

The purpose of this study is to investigate predisposing factors for the head and neck infections (HNIs), regarding to the demographic data, anatomical spaces, microbiology and antibiotic sensitivity for affected patients.

MATERIAL AND METHODS

A 13-year of retrospective study evaluating 470 patients with HNIs, treated as inpatient management in the Department of Oral and Maxillofacial Surgery of KyungHee University school of Dentistry, Seoul, Korea, from January 2009 to February 2022. Statistical analysis of demographic, time-related, anatomic, microbiologic, and treatment variables were investigated for each patient.

RESULTS

The frequency of HNIs was significantly higher in 50's in males, followed by 70's in females. High Severity score (SS) were significantly associated with increased LOH (Length of hospital stay) and LOM (Length of medication), while LOH showed more intensive relationship compared with LOM. The most frequently involved space in abscess was submandibular space, though incidence and severity of HNIs shows declining tendency throughout 13-year research. Streptococcus viridans was the most predominant species isolated from pus culture growth, and a combination of ampicillin and sulbactam was the 1st choice of antibiotics intravenously. According to the comparison analysis between recommended antibiotics from resistance testing result and clinically administered antibiotics, final coincidence rate was estimated about 55%.

CONCLUSIONS

Due to HNIs being multifactorial, predicting progression and management of HNIs is still a challenge for oral and maxillofacial surgeons. The present study showed several predisposing factors of SHNIs and their correlations, which could contribute to earlier diagnosis and more effective treatment planning for clinicians, thereby leading to the improvement of prognosis for patients, ultimately.

Long-wave infrared transparent sulfur polymers enabled by symmetric thiol cross-linker

Infrared (IR) transmissive polymeric materials for optical elements require a balance between their optical properties, including refractive index (n) and IR transparency, and thermal properties such as glass transition temperature (T_g). Achieving both a high refractive index (n) and IR transparency in polymer materials is a very difficult challenge. In particular, there are significant complexities and considerations to obtaining organic materials that transmit in the long-wave infrared (LWIR) region, because of high optical losses due to the IR absorption of the organic molecules. Our differentiated strategy to extend the frontiers of LWIR transparency is to reduce the IR absorption of the organic moieties. The proposed approach synthesized a sulfur copolymer via the inverse vulcanization of 1,3,5-benzenetrithiol (BTT), which has a relatively simple IR absorption because of its symmetric structure, and elemental sulfur, which is mostly IR inactive. This strategy resulted in approximately 1 mm thick windows with an ultrahigh refractive index (n_av > 1.9) and high mid-wave infrared (MWIR) and LWIR transmission, without any significant decline in thermal properties. Furthermore, we demonstrated that our IR transmissive material was sufficiently competitive with widely used optical inorganic and polymeric materials.

Effects on the Thermo-Mechanical and Interfacial Performance of Newly Developed PI-Sized Carbon Fiber–Polyether Ether Ketone Composites: Experiments and Molecular Dynamics Simulations

In this study, polyether ether ketone (PEEK) composites reinforced with newly developed water-dispersible polyimide (PI)-sized carbon fibers (CFs) were developed to enhance the effects of the interfacial interaction between PI-sized CFs and a PEEK polymer on their thermo-mechanical properties. The PI sizing layers on these CFs may be induced to interact vigorously with the p-phenylene groups of PEEK polymer chains because of increased electron affinity. Therefore, these PI-sized CFs are effective for improving the interfacial adhesion of PEEK composites. PEEK composites were reinforced with C-CFs, de-CFs, and PI-sized CFs. The PI-sized CFs were prepared by spin-coating a water-dispersible PAS suspension onto the de-CFs, followed by heat treatment for imidization. The composites were cured using a compression molding machine at a constant temperature and pressure. Atomic force and scanning electron microscopy observations of the structures and morphologies of the carbon fiber surfaces verified the improvement of their thermo-mechanical properties. Molecular dynamics simulations were used to investigate the effects of PI sizing agents on the stronger interfacial interaction energy between the PI-sized CFs and the PEEK polymer. These results suggest that optimal amounts of PI sizing agents increased the interfacial properties between the CFs and the PEEK polymer.

Mycobacterial Regulatory Systems Involved in the Regulation of Gene Expression Under Respiration-Inhibitory Conditions

Mycobacterium tuberculosis is the causative agent of tuberculosis. M. tuberculosis can survive in a dormant state within the granuloma, avoiding the host-mounting immune attack. M. tuberculosis bacilli in this state show increased tolerance to antibiotics and stress conditions, and thus the transition of M. tuberculosis to the nonreplicating dormant state acts as an obstacle to tuberculosis treatment. M. tuberculosis in the granuloma encounters hostile environments such as hypoxia, nitric oxide, reactive oxygen species, low pH, and nutrient deprivation, etc., which are expected to inhibit respiration of M. tuberculosis. To adapt to and survive in respiration-inhibitory conditions, it is required for M. tuberculosis to reprogram its metabolism and physiology. In order to get clues to the mechanism underlying the entry of M. tuberculosis to the dormant state, it is important to understand the mycobacterial regulatory systems that are involved in the regulation of gene expression in response to respiration inhibition. In this review, we briefly summarize the information regarding the regulatory systems implicated in upregulation of gene expression in mycobacteria exposed to respiration-inhibitory conditions. The regulatory systems covered in this review encompass the DosSR (DevSR) two-component system, SigF partner switching system, MprBA-SigE-SigB signaling pathway, cAMP receptor protein, and stringent response.

Adaptive autophagy reprogramming in Schwann cells during peripheral demyelination

The myelin sheath is an essential structure for the rapid transmission of electrical impulses through axons, and peripheral myelination is a well-programmed postnatal process of Schwann cells (SCs), the myelin-forming peripheral glia. SCs transdifferentiate into demyelinating SCs (DSCs) to remove the myelin sheath during Wallerian degeneration after axonal injury and demyelinating neuropathies, and macrophages are responsible for the degradation of myelin under both conditions. In this study, the mechanism by which DSCs acquire the ability of myelin exocytosis was investigated. Using serial ultrastructural evaluation, we found that autophagy-related gene 7-dependent formation of a "secretory phagophore (SP)" and tubular phagophore was necessary for exocytosis of large myelin chambers by DSCs. DSCs seemed to utilize myelin membranes for SP formation and employed p62/sequestosome-1 (p62) as an autophagy receptor for myelin excretion. In addition, the acquisition of the myelin exocytosis ability of DSCs was associated with the decrease in canonical autolysosomal flux and was demonstrated by p62 secretion. Finally, this SC demyelination mechanism appeared to also function in inflammatory demyelinating neuropathies. Our findings show a novel autophagy-mediated myelin clearance mechanism by DSCs in response to nerve damage.

Coordination of pancreatic islet rhythmic activity by delayed negative feedback

Secretion of insulin from the pancreas is pulsatile, driven by intrinsic oscillations within individual islets of Langerhans. The secretions are coordinated among the many islets distributed throughout the pancreas producing a synchronized rhythm in vivo that is essential for maintaining normal glucose levels. One hypothesized mechanism for the coordination of islet activity is negative feedback, whereby sequestration of glucose in response to elevated insulin leads to a reduction in the blood glucose level that is sensed by the islet population. This global signal of glucose then coordinates the individual islets. In this study, we tested how this coordination mechanism is affected by time delays in the negative feedback, using a microfluidic system to monitor Ca2+ levels in a small population of islets and implementing glucose control through a negative feedback system. We found that islet synchronization occurs even with time delays in the feedback of up to 7 min. We also found that a second, slower closed-loop oscillation period is produced during delayed feedback in which islet oscillations are clustered into episodes. The period of this second oscillatory mode increases with the time delay and appears to be a second stable behavior that coexists with the faster synchronized oscillation. The general conclusion is that islet coordination through negative feedback is a viable means of islet coordination that is robust to delays in the timing of the feedback, and could complement other potential coordination mechanisms such as entrainment by pancreatic ganglia.NEW & NOTEWORTHY Insulin secretion from islets of Langerhans is rhythmic, and these rhythms are coordinated to produce oscillatory plasma insulin levels. Using a combination of microfluidics and computational modeling, we demonstrate that coordination can occur through negative feedback of the type provided by the liver, even if that feedback is delayed by several minutes. We also demonstrate that a second, slower, mode of oscillations can occur when feedback is delayed where faster oscillations are grouped into episodes.

Negative regulation of the acsA1 gene encoding the major acetyl-CoA synthetase by cAMP receptor protein in Mycobacterium smegmatis

Acetyl-CoA synthetase (ACS) is the enzyme that irreversibly catalyzes the synthesis of acetyl-CoA from acetate, CoA-SH, and ATP via acetyl-AMP as an intermediate. In this study, we demonstrated that AcsA1 (MSMEG_6179) is the predominantly expressed ACS among four ACSs (MSMEG_6179, MSMEG_0718, MSMEG_3986, and MSMEG_5650) found in Mycobacterium smegmatis and that a deletion mutation of acsA1 in M. smegmatis led to its compromised growth on acetate as the sole carbon source. Expression of acsA1 was demonstrated to be induced during growth on acetate as the sole carbon source. The acsA1 gene was shown to be negatively regulated by Crp1 (MSMEG_6189) that is the major cAMP receptor protein (CRP) in M. smegmatis. Using DNase I footprinting analysis and site-directed mutagenesis, a CRP-binding site (GGTGA-N₆-TCACA) was identified in the upstream regulatory region of acsA1, which is important for repression of acsA1 expression. We also demonstrated that inhibition of the respiratory electron transport chain by inactivation of the major terminal oxidase, aa₃ cytochrome c oxidase, led to a decrease in acsA1 expression probably through the activation of CRP. In conclusion, AcsA1 is the major ACS in M. smegmatis and its gene is under the negative regulation of Crp1, which contributes to some extent to the induction of acsA1 expression under acetate conditions. The growth of M. smegmatis is severely impaired on acetate as the sole carbon source under respiration-inhibitory conditions.

Assessment of acute and non-acute suicide crisis symptoms: Validation of the Korean version of the acute suicidal affective disturbance inventory

Suicide risk assessment is predominantly based on assessing current/recent suicidal ideation and past suicidal behavior. However, suicidal ideation and lifetime suicide attempt are poor predictors of imminent suicide risk or crisis. The acute suicidal affective disturbance inventory-lifetime (ASADI-L) was developed to assess symptoms of acute suicidal affective disturbance, which includes a drastic increase in suicidal intent, perceptions of social and/or self-alienation, hopelessness, and overarousal. However, the ASADI-L has not yet been validated in a Korean population. Also, the ASADI-L has only been validated for people who experience a drastic increase in suicidal intention over the course of hours or days (i.e., the acute suicidal intention group) and not validated for those who experience suicidal intention for a longer period (i.e., the non-acute suicidal intention group). Thus, the aims of this study were to (1) validate the ASADI-L in a sample of Korean community adults; and (2) compare clinical characteristics of the acute and non-acute suicidal intention groups. Among 1,675 community adults, data from 682 participants who reported a lifetime drastic increase in suicidal intent were analyzed. Results indicated that the ASADI-L has relevant reliability, validity, and a unidimensional factor structure. The acute suicidal intention group had higher ASAD symptoms as well as clinical symptoms than the non-acute group, but the two groups did not differ in history of suicide attempt. Overall, these findings suggest that the ASADI-L is a valid measure of acute and non-acute suicidal affective disturbance among Korean adults. Further investigation of the differences in acute and non-acute suicide risk is warranted.

Multifunctional-high resolution imaging plate based on hydrophilic graphene for digital pathology

In the present study, we showed that hydrophilic graphene can serve as an ideal imaging plate for biological specimens. Graphene being a single-atom-thick semi-metal with low secondary electron emission, array tomography analysis of serial sections of biological specimens on a graphene substrate showed excellent image quality with improvedz-axis resolution, without including any conductive surface coatings. However, the hydrophobic nature of graphene makes the placement of biological specimens difficult; graphene functionalized with polydimethylsiloxane oligomer was fabricated using a simple soft lithography technique and then processed with oxygen plasma to provide hydrophilic graphene with minimal damage to graphene. High-quality scanning electron microscopy images of biological specimens free from charging effects or distortion were obtained, and the optical transparency of graphene enabled fluorescence imaging of the specimen; high-resolution correlated electron and light microscopy analysis of the specimen became possible with the hydrophilic graphene plate.

P10.07.B Differential YAP activity in human glioblastoma tumorspheres

Background

Although glioblastoma (GBM) is the most common primary brain tumor, the best available treatment options are still associated with poor prognosis. Recently, the Hippo/YAP signaling pathway has been emerged as an important driver of GBM. Nevertheless, extensive studies have not yet been focused on the importance of phosphorylation event in regulating endogenous YAP activity in GBM. Here, we sought to elucidate that the modulation and stabilization of YAP/TAZ in Hippo pathway promotes GBM progression.

Material and Methods

Expression patterns of YAP1, TAZ, CTGF, TEAD4 and LATS1 mRNA were confirmed in human normal and GBM tissue, and patient survival according to YAP1 expression was confirmed in TCGA and Severance cohort. The YAP1 expression patterns in several TSs were classified into SOH and AH according to transcriptome analysis and western blot. For each classified TSs, the characteristics of SOH and AH were comparatively analyzed through immunoprecipitation, nucleus fraction, TEAD4 luciferase assay, and confocal analysis. The effect of YAP1 knockdown/out and overexpression in SOH and AH TSs were measured by WST/ATP analysis, 3D invasion and neurosphere formation, and western blot. In addition, the drug reactivity of SOH and AH TSs was examined by treatment with the YAP1 inhibitors Peptide17 and verteporfin, and the effects of Peptide17, verteporfin and YAP1-shRNA were examined in in-vivo xenograft model.

Results

YAP1 mRNA levels including TAZ, CTGF, TEAD4 and LATS1 were higher in GBM than in normal tissues. Through transcriptome analysis and western blot, TS can be divided into SOH and AH groups according to the expression level of CTGF, but not YAP1 level. In the case of SOH TS, the binding of TEAD4 was strong in immunoprecipitation, the ratio of YAP1 was higher in the nucleus in the nucleus fractionation and confocal analysis, and the luciferase activity of TEAD4 was high in the TEAD4 luciferase assay. On the other hand, in the case of TS of AH, the opposite trend was observed. When YAP1 was knocked down or out, the proliferation, invasion, and stemness of TS tended to be decrease more in SOH TS than in AH TS, and SOH TS showed more sensitive drug response even in Peptide17 and Verteporfin treatment. In the case of YAP1 overexpression, the opposite trend was observed in SOH TS. In the in-vivo xenograft model, injection of Peptide17, verteporfin, and YAP1-shRNA showed a tendency to increase the survival rate of mice.

Conclusion

The association of YAP has been described in several cancers, but there has been no study comparing GBM TS by YAP expression and classifying it at the functional level. Now, for the first time, we show that the characteristics of GBM TS can be predicted according to the expression value of YAP, respectively, and YAP is expected to be applied as an important prognostic factor for GBM treatment in the future.

Ultrahigh strength, modulus, and conductivity of graphitic fibers by macromolecular coalescence

Theoretical considerations suggest that the strength of carbon nanotube (CNT) fibers be exceptional; however, their mechanical performance values are much lower than the theoretical values. To achieve macroscopic fibers with ultrahigh performance, we developed a method to form multidimensional nanostructures by coalescence of individual nanotubes. The highly aligned wet-spun fibers of single- or double-walled nanotube bundles were graphitized to induce nanotube collapse and multi-inner walled structures. These advanced nanostructures formed a network of interconnected, close-packed graphitic domains. Their near-perfect alignment and high longitudinal crystallinity that increased the shear strength between CNTs while retaining notable flexibility. The resulting fibers have an exceptional combination of high tensile strength (6.57 GPa), modulus (629 GPa), thermal conductivity (482 W/m·K), and electrical conductivity (2.2 MS/m), thereby overcoming the limits associated with conventional synthetic fibers.

Surface Modification of Sulfur-Assisted Reduced Graphene Oxide with Poly(phenylene sulfide) for Multifunctional Nanocomposites

The sulfur on the sulfur-assisted reduced graphene oxide (SrGO) surface provides the origin of poly(phenylene sulfide) PPS-grafting via S_NAr mechanism. In-situ polymerization from sulfur on SrGO afforded surface modification of SrGO, resulting in enhanced dispersibility in PPS. The tensile strength, electrical and thermal conductivities, and flame retardancy of PPS-coated SrGO were efficiently enhanced using highly concentrated SrGO and masterbatch (MB) for industrial purposes. Three-dimensional X-ray microtomography scanning revealed that diluting MB in the PPS resin afforded finely distributed SrGO across the PPS resin, compared to the aggregated state of graphene oxide. For the samples after dilution, the thermal conductivity and flame retardancy of PPS/SrGO are preserved and typically enhanced by up to 20%. The proposed PPS/SrGO MB shows potential application as an additive for reinforced PPS due to the ease of addition during the extrusion process.

Potential neuron-autonomous Purkinje cell degeneration by 2',3'-cyclic nucleotide 3'-phosphodiesterase promoter/Cre-mediated autophagy impairments

Studies of neuroglial interaction largely depend on cell-specific gene knockout (KO) experiments using Cre recombinase. However, genes known as glial-specific genes have recently been reported to be expressed in neuroglial stem cells, leading to the possibility that a glia-specific Cre driver results in unwanted gene deletion in neurons, which may affect sound interpretation. 2',3'-Cyclic nucleotide 3'-phosphodiesterase (CNP) is generally considered to be an oligodendrocyte (OL) marker. Accordingly, Cnp promoter-controlled Cre recombinase has been used to create OL-specific gene targeting mice. However, in this study, using Rosa26-tdTomato-reporter/Cnp-Cre mice, we found that many forebrain neurons and cerebellar Purkinje neurons belong to the lineages of Cnp-expressing neuroglial stem cells. To answer whether gene targeting by Cnp-Cre can induce neuron-autonomous defects, we conditionally deleted an essential autophagy gene, Atg7, in Cnp-Cre mice. The Cnp-Cre-mediated Atg7 KO mice showed extensive p62 inclusion in neurons, including cerebellar Purkinje neurons with extensive neurodegeneration. Furthermore, neuronal areas showing p62 inclusion in Cnp-Cre-mediated Atg7 KO mice overlapped with the neuronal lineage of Cnp-expressing neuroglial stem cells. Moreover, Cnp-Cre-mediated Atg7-KO mice did not develop critical defects in myelination. Our results demonstrate that a large population of central neurons are derived from Cnp-expressing neuroglial stem cells; thus, conditional gene targeting using the Cnp promoter, which is known to be OL-specific, can induce neuron-autonomous phenotypes.

OP0274-PARE EVALUATION OF PATIENT SATISFACTION FOR TELEHEALTH (PHONE AND VIDEO) IN RHEUMATOLOGY OUTPATIENTS DURING COVID-19 PANDEMIC

Background:

Telehealth via phone (TPhone) or video conference (TVideo) in rheumatology has been a topic of interest for many years. Its use was rapidly expanded due to the international public health emergency of coronavirus disease-19 (COVID-19) outbreak in 2020. Australian Medicare Benefits Schedule (MBS) swiftly enabled temporary MBS telehealth items on 13 March 2020, currently extended until 31 March 20211. In the early phase of the COVID-19 pandemic, Antony et al. conducted a single-centre public survey to assess patient perception of rheumatology telehealth. Their results showed that 98.4% of patients consider telehealth acceptable during the pandemic2. It is unclear, however, whether this positive perception persists after patients experience a telehealth. In addition, a survey data in 2019 suggested more than half of Australian rheumatologists work in private practice3. Therefore, inclusion of private patients will better represent patient perception of telehealth.

Objectives:

The aim of this study was to evaluate patient satisfaction with telehealth during the COVID-19 pandemic. This would determine its feasibility to be integrated in future rheumatology outpatient model.

Methods:

A questionnaire containing 30 questions was sent to rheumatology patients who attended telehealth appointments at a level 2 public hospital and a local private clinic between April and May 2020. The questionnaires aimed to obtain information on baseline demographics (sex, age, public or private patient, employment status, visual or auditory impairment), appointment details (TPhone or TVideo, usual arrangement for face-to-face (F2F) appointment, cost effectiveness) and appointment satisfaction using a 5-point Likert scale. Descriptive statistical analysis was conducted.

Results:

The questionnaire was sent to 1452 patients, of which 494 patients responded (34%). Female predominance (77.1%) and a higher proportion of TPhone (79.1%) was seen in the respondents. A majority of patients were existing patients known to the services (90.9%). More than 70% of responses indicated overall satisfaction in specialist care via telehealth, and 88.7% perceived this suitable during a pandemic. Of all respondents, 21.7% were prescribed new medication, and the majority of these patients were confident in taking the new medication after the telehealth appointment. Future acceptability for TPhone was significantly lower in private patients compared to public patients (p= 0.01). Subgroup analysis revealed that higher telehealth satisfaction was associated with needing to take time off work to attend face-to-face appointment (p= 0.02), perception of cost effectiveness (p<0.001) and TVideo (p=0.03).

Conclusion:

This is the first study which included both public and private rheumatology patients to evaluate patient satisfaction for telehealth during the COVID-19 pandemic. Overall high level of satisfaction was seen in telehealth most notably associated with its cost effectiveness. A higher percentage of patients who had TVideo compared to TPhone were receptive to future telehealth via TVideo, supportive of the importance of visual cues. This in turn will have significant administrative and technological burdens to coordinate in comparison to a F2F or TPhone review. This qualitative study provides valuable insight of patient perception of telehealth, which has the potential to compliment the traditional rheumatology outpatient model of care following the pandemic.

References:

[1]COVID-19 Temporary MBS Telehealth Services 2020 [Available from: http://www.mbsonline.gov.au/internet/mbsonline/publishing.nsf/Content/Factsheet-TempBB.

[2]Antony A, Connelly K, De Silva T, Eades L, Tillett W, Ayoub S, et al. Perspectives of Patients With Rheumatic Diseases in the Early Phase of COVID-19. Arthritis Care & Research. 2020;72(9):1189-95.

[3]Association AR. Workforce Survey Exective Summary 2019 2019 [Available from: https://rheumatology.org.au/members/documents/WorkforceSurveyExecutiveSummary-websiteMay2019.pdf.

Acknowledgements:

University of Queensland

Nursing staff at Redcliffe Hospital and Administration officers at Redcliffe & Northside Rheumatology

Disclosure of Interests:

None declared

Improved Constraints on Global Methane Emissions and Sinks Using δ 13C-CH4

We study the drivers behind the global atmospheric methane (CH4) increase observed after 2006. Candidate emission and sink scenarios are constructed based on proposed hypotheses in the literature. These scenarios are simulated in the TM5 tracer transport model for 1984-2016 to produce three-dimensional fields of CH4 and δ 13C-CH4, which are compared with observations to test the competing hypotheses in the literature in one common model framework. We find that the fossil fuel (FF) CH4 emission trend from the Emissions Database for Global Atmospheric Research 4.3.2 inventory does not agree with observed δ 13C-CH4. Increased FF CH4 emissions are unlikely to be the dominant driver for the post-2006 global CH4 increase despite the possibility for a small FF emission increase. We also find that a significant decrease in the abundance of hydroxyl radicals (OH) cannot explain the post-2006 global CH4 increase since it does not track the observed decrease in global mean δ 13C-CH4. Different CH4 sinks have different fractionation factors for δ 13C-CH4, thus we can investigate the uncertainty introduced by the reaction of CH4 with tropospheric chlorine (Cl), a CH4 sink whose abundance, spatial distribution, and temporal changes remain uncertain. Our results show that including or excluding tropospheric Cl as a 13 Tg/year CH4 sink in our model changes the magnitude of estimated fossil emissions by ∼20%. We also found that by using different wetland emissions based on a static versus a dynamic wetland area map, the partitioning between FF and microbial sources differs by 20 Tg/year, ∼12% of estimated fossil emissions.

Quantifying the clinical severity of immune-related cutaneous adverse events in clinical trial patients: A prospective study using 3D-total body photography

e13548

Background: Accurate and comprehensive assessment of dermatologic adverse events (AEs) in clinical trials is challenging, given the heterogeneity of appearance and perception of these AEs. For dermatologic AEs, Common Terminology Criteria for Adverse Events (CTCAE) grading of clinical severity primarily relies on the clinician’s reporting of body surface area involved (BSA%) estimated by visual assessment combined with clinician’s interpretation of psychosocial impact, which can vary among raters. Although patient reported outcome (PRO-CTCAE) and QoL (SKINDEX-16) measures have been incorporated to improve accuracy and reliability of symptomatic AE evaluations, the subjective nature of dermatologic CTCAE grading remains. Clinical photography is routinely used to aid in visual comparison but cannot be incorporated to standardized measures due to inconsistencies in lighting, distance from the camera, and position. This prospective study aims to validate the accuracy and utility of affected BSA% using 3D-total body photography (TBP) and quantitative imaging analytics for standardized, objective assessment of immune-related cutaneous adverse events (ircAE) in clinical trials and/or prospective studies. Methods: Polarized and non-polarized TBPs (Canfield Vectra WB360) were acquired on two dermatology clinic visits 2-6 weeks apart (n = 8, to date). CTCAE, PRO-CTCAE, SKINDEX-16 were evaluated by one investigator for both visits. Image analysis including BSA% calculation was conducted using Vectra measurement software by an investigator blinded to clinical grades. Means and ranges for change in CTCAE, BSA%, and SKINDEX-16 were calculated. Results: To date, 29 patients with ircAE have been enrolled with 8 completing both visits. A greater improvement in affected BSA% (-1.9, -13.0, -20.1) and SKINDEX-16 (-8,-11.9,-19.5) were associated with a greater degree of clinical improvement measured by CTCAE (0 to -3). Widest range in the degree of change in BSA% (-24.4, -6.8) and SKINDEX-16 (-31,19) was observed in the group with intermediate change in CTCAE (-2 to -1, n = 5). Conclusions: Estimating affected BSA% via visual assessment is subject to human error and rely on memory or comparison with unstandardized photos to detect clinical improvement of dermatologic conditions. This poses a challenge particularly for cases with mild or moderate clinical improvement, demonstrated by the wide range in the degree of change for BSA% and SKINDEX-16. With consistent lighting, position, and objective measurements, 3D-TBP quantitative image analysis shows promise in reproducible, standardized monitoring and quantification of ircAE clinical severity. Furthermore, the quantitative nature of TBP measurement suggests its potential utility for correlation with underlying immunophenotyping correlative studies and clinical trials.

Dermatologic adverse events of brentuximab vedotin: Characteristics, management, and their relationship with dose regimen

3049

Background: Owing to its high efficacy and tolerability, brentuximab vedotin (BV) is increasingly being favored over other aggressive systemic therapies for the treatment of various CD30+ Hodgkin and non-Hodgkin lymphomas, including peripheral T-cell lymphoma and cutaneous T-cell lymphomas. Dermatologic adverse events (dAE) are one of the most common toxicities associated with BV but data regarding their characteristics including correlation to dose, time to occurrence, and management is scarce. We aim to describe the clinical and pathologic characteristics of dAEs associated with BV, their relationship with administered dose regimen, and available management strategies. Methods: An IRB-approved retrospective analysis was conducted for all patients who had received at least one cycle of BV from Memorial Sloan Kettering Cancer Center in 2009-2020. Logistic regression, χ2, student’s t-test were performed for univariate analyses. Kaplan-Meier survival and multivariate Cox proportional hazard model evaluated dAE occurrence stratified by 5 major dose regimens (single cycle, 1.2mg q1w, 1.2mg q2w, 1.2mg q3w, 1.8mg q3w). Results: Of 611 patients, 201 experienced dAE with median time-to-event of 24 days and 29% experiencing > 1 dAEs. Rash was the most common (62%; 142/230), followed by alopecia (20%) and xerosis (13%). For rash, 50% reported involvement of only the extremities and/or acral sites compared to 25% who had generalized rash. Of those reported (111), 68 patients had grade 1 dAE (61%), 38 grade 2 (34%), and 5 grade 3 (5%)-all grade 3 were rash (maculopapular/morbilliform). 14 cases (7%) resulted in treatment interruptions and 6 in discontinuations due to dAEs (3%). Pathology were often nonspecific consistent with a hypersensitivity reaction: spongiotic/psoriasiform dermatitis with perivascular lymphocytic infiltrates . Patients undergoing weekly regimen were at a statistically and clinically significantly higher risk of dAE during the first 100 days of BV treatment (p = 0.001). Between the two most frequently administered dose regimens (1.8mg vs. 1.2mg, q3w), the higher dose carried 105% higher risk for dAE (HR: 2.047, p = 0.053). Those who had received a single cycle of BV had the lowest risk compared to all other regimen (1/42, p = 0.001). Topical and/or systemic steroids were most frequently prescribed (43%) with 12% of patients requiring systemic steroids. Other treatments varied ranging from antihistamines to moisturizers. Conclusions: Understanding of the detailed characteristics, management strategies, dose-dependent effects associated with BV is critical to provide clinical guidance for primary providers and minimize treatment interruptions or discontinuations. The results overall suggest that the risk for dAEs is dose-dependent with those undergoing frequent dosing regimens having a greater risk, although most dAEs remain mild or low-grade.

Article Topic/Title: Primary cutaneous T-cell lymphomas other than Mycosis Fungoides and Sezary Syndrome. Part II: Prognosis and Management

Primary cutaneous T-cell lymphomas (CTCLs) other than Mycosis Fungoides (MF) and Sézary syndrome (SS) encompass a heterogenous group of non-Hodgkin lymphomas with variable clinical course, prognoses, and management. With morphologic and histologic overlap among the CTCL subtypes and other T-cell lymphomas with cutaneous manifestations, thorough evaluation with clinicopathologic correlation and exclusion of systemic involvement are essential prior to initiating therapy. Staging and treatment recommendations vary depending on the subtype, clinical behavior, and treatment response. Generally, for subtypes where staging is recommended, Ann Arbor or TNM staging specific to CTCL other than MF or SS are used. For many subtypes, there is no standard treatment to date. Available recommended treatments range widely from no active or minimal intervention with skin-directed therapy to aggressive systemic therapies including multiagent chemotherapy with consideration for hematopoietic stem cell transplant. Emerging targeted therapies, such as brentuximab, a chimeric antibody targeting CD30, show promise in altering the disease course of non-MF/SS CTCLs.

Primary cutaneous T-cell lymphomas other than Mycosis Fungoides and Sezary Syndrome - Part I: Clinical and histologic features and diagnosis

Primary cutaneous T-cell lymphomas (CTCLs) are defined as lymphomas with a T-cell phenotype that present in the skin without evidence of systemic or extracutaneous disease at initial presentation. CTCLs other than Mycosis Fungoides (MF) and Sézary syndrome (SS) account for approximately one-third of CTCLs and encompass a heterogenous group of non-Hodgkin lymphomas ranging from indolent lymphoproliferative disorders to aggressive malignancies with a poor prognosis. The spectrum of CTCLs continues to broaden as new provisional entities are classified. Given the morphologic and histologic overlap among CTCLs and other diagnoses, a thorough clinical history, physical evaluation, and clinicopathologic correlation are essential in the workup and diagnosis of these rare entities. This article will summarize the epidemiologic, clinical, pathologic, and diagnostic features of CTCLs other than MF and SS.

Identification of efficient prokaryotic cell-penetrating peptides with applications in bacterial biotechnology

In bacterial biotechnology, instead of producing functional proteins from plasmids, it is often necessary to deliver functional proteins directly into live cells for genetic manipulation or physiological modification. We constructed a library of cell-penetrating peptides (CPPs) capable of delivering protein cargo into bacteria and developed an efficient delivery method for CPP-conjugated proteins. We screened the library for highly efficient CPPs with no significant cytotoxicity in Escherichia coli and developed a model for predicting the penetration efficiency of a query peptide, enabling the design of new and efficient CPPs. As a proof-of-concept, we used the CPPs for plasmid curing in E. coli and marker gene excision in Methylomonas sp. DH-1. In summary, we demonstrated the utility of CPPs in bacterial engineering. The use of CPPs would facilitate bacterial biotechnology such as genetic engineering, synthetic biology, metabolic engineering, and physiology studies.

Lee et al. construct a cell-penetrating peptides (CPP) library and identify CPPs that can penetrate bacterial cells with minimum or no impact on cell viability. For the identified top CPP candidates, their abilities to deliver macromolecules such as I-SceI and Cre recombinase proteins to bacteria are evaluated as proof-of-concept studies for potential applications.

Non-Māori-speaking New Zealanders have a Māori proto-lexicon

We investigate implicit vocabulary learning by adults who are exposed to a language in their ambient environment. Most New Zealanders do not speak Māori, yet are exposed to it throughout their lifetime. We show that this exposure leads to a large proto-lexicon - implicit knowledge of the existence of words and sub-word units without any associated meaning. Despite not explicitly knowing many Māori words, non-Māori-speaking New Zealanders are able to access this proto-lexicon to distinguish Māori words from Māori-like nonwords. What's more, they are able to generalize over the proto-lexicon to generate sophisticated phonotactic knowledge, which lets them evaluate the well-formedness of Māori-like nonwords just as well as fluent Māori speakers.

The Partner Switching System of the SigF Sigma Factor in Mycobacterium smegmatis and Induction of the SigF Regulon Under Respiration-Inhibitory Conditions

The partner switching system (PSS) of the SigF regulatory pathway in Mycobacterium smegmatis has been previously demonstrated to include the anti-sigma factor RsbW (MSMEG_1803) and two anti-sigma factor antagonists RsfA and RsfB. In this study, we further characterized two additional RsbW homologs and revealed the distinct roles of three RsbW homologs [RsbW1 (MSMEG_1803), RsbW2 (MSMEG_6129), and RsbW3 (MSMEG_1787)] in the SigF PSS. RsbW1 and RsbW2 serve as the anti-sigma factor of SigF and the protein kinase phosphorylating RsfB, respectively, while RsbW3 functions as an anti-SigF antagonist through its protein interaction with RsbW1. Using relevant mutant strains, RsfB was demonstrated to be the major anti-SigF antagonist in M. smegmatis. The phosphorylation state of Ser-63 was shown to determine the functionality of RsfB as an anti-SigF antagonist. RsbW2 was demonstrated to be the only protein kinase that phosphorylates RsfB in M. smegmatis. Phosphorylation of Ser-63 inactivates RsfB to render it unable to interact with RsbW1. Our comparative RNA sequencing analysis of the wild-type strain of M. smegmatis and its isogenic Δaa₃ mutant strain lacking the aa₃ cytochrome c oxidase of the respiratory electron transport chain revealed that expression of the SigF regulon is strongly induced under respiration-inhibitory conditions in an RsfB-dependent way.

Analysis of the effect of organic solvent-sheet interfacial interaction on the exfoliation of sulfur-doped reduced graphene oxide sheets in a solvent system using molecular dynamics simulations

In this study, the effect of interfacial interaction between solvent and sheets on the exfoliation of sulfur-doped reduced graphene oxide (SrGO) sheets was studied, using molecular dynamics simulations. Four organic solvents of toluene, tetrahydrofuran, N-methyl-2-pyrrolidone, and sulfolane, were used in this simulation. An insertion simulation considering the size effect of insertion molecules was used to determine the insertion efficiency of the solvent molecules. The insertion efficiency of toluene was the best among the four solvents due to the influence of the effective thickness of the solvent. An exfoliation simulation considering electrostatic interaction was conducted to evaluate the exfoliation efficiency of the SrGO sheets. Unlike the insertion efficiency case, the sulfolane was found to have the best exfoliation efficiency among the four solvents, due to the strong electrostatic repulsion and weak attractive energy between the SrGO sheets. The exfoliation efficiency of the SrGO sheets was improved by increasing the sulfur content and the ratio of the thiol type to the total number of sulfur-doped groups. These results reveal that decreasing the attractive energy and increasing the electrostatic repulsion between the solvent and SrGO sheets are a useful way to improve the exfoliation efficiency of SrGO sheets.

Influences of carboxyl functionalization of intercalators on exfoliation of graphite oxide: a molecular dynamics simulation

In this study, the influences of the carboxyl functionalization of intercalators on exfoliation of graphite oxide were analyzed using molecular dynamics (MD) simulations.