Airborne antibiotic and metal resistance genes - A neglected potential risk at e-waste recycling facilities

Heavy metal-rich environments can promote the selection of metal-resistance genes (MRGs) in bacteria, often leading to the simultaneous selection of antibiotic-resistance genes (ARGs) through a process known as co-selection. To comprehensively evaluate the biological pollutants at electronic-waste (e-waste) recycling facilities, air, soil, and river samples were collected at four distinct Swiss e-waste recycling facilities and analyzed for ARGs, MRGs, mobile genetic elements (MGEs), endotoxins, and bacterial species, with correlations drawn to heavy metal occurrence. To our knowledge, the present work marks the first attempt to quantify these bio-pollutants in the air of e-waste recycling facilities, that might pose a significant health risk to workers. Although ARG and MRG's profiles varied among the different sample types, intl1 consistently exhibited high relative abundance rates, identifying it as the predominant MGE across all sample types and facilities. These findings underscore its pivol role in driving diverse bacterial adaptations to extreme heavy metal exposure by selection and dissemination of ARGs and MRGs. All air samples exhibited consistent profiles of ARGs and MRGs, with blaTEM emerging as the predominant ARG, alongside pbrT and nccA as the most prevalent MRGs. However, one facility, engaged in batteries recycling and characterized by exceptionally high concentrations of heavy metals, showcased a more diverse resistance gene profile, suggesting that bacteria in this environment required more complex resistance mechanisms to cope with extreme metal exposure. Furthermore, this study unveiled a strong association between gram-negative bacteria and ARGs and less with MRGs. Overall, this research emphasizes the critical importance of studying biological pollutants in the air of e-waste recycling facilities to inform robust safety measures and mitigate the risk of resistance gene dissemination among workers. These findings establish a solid foundation for further investigations into the complex interplay among heavy metal exposure, bacterial adaptation, and resistance patterns in such distinctive ecosystems.

Performance optimization and nitrogen removal mechanism of up-flow partial denitrification/anammox process

This study aimed to remediate the problems of sludge floating and uneven mass transfer in up-flow partial denitrification/anammox (PDA) reactors and dissect the nitrogen removal mechanism. Two up-flow PDA reactors were operated, whereby in R1 combined biological carriers were added, while in R2 mechanical stirring was applied, the reactors were inoculated with PD sludge and anammox sludge. Results showed the TN removal rates at the end of the operation were 89% (R1) and 92% (R2). The addition of both strategies suppressed the occurrence of sludge upwelling and deterioration of settling performance, even when the granule diameter of the granular zone in R1 and R2 reached 1.921 and 2.006 mm, respectively. 16SrRNA sequencing revealed R1 had a higher abundance of anammox bacteria (AAOB, 14.53%-R1, 9.06%-R2, respectively), and R2 had a higher quantity of denitrifying bacteria (61.92%-R1, 67.11%-R2, respectively). And the nitrogen removal was contributed by anammox and denitrification in combination, with contributions of 82.17%, 17.83% (R1), and 85.07%, 14.93% (R2), respectively. In summary, both strategies prevented sludge flotation and uneven nitrogen mass transfer. However, mechanical agitation had a more substantial positive effect on the performance of PDA than the addition of biocarriers because it achieved a more adequate mass transfer.

Spatial and temporal distribution of endotoxins, antibiotic resistance genes and mobile genetic elements in the air of a dairy farm in Germany

Antimicrobial resistance (AMR) is a serious issue that is continuously growing and spreading, leading to a dwindling number of effective treatments for infections that were easily treatable with antibiotics in the past. Animal farms are a major hotspot for AMR, where antimicrobials are often overused, misused, and abused, in addition to overcrowding of animals. In this study, we investigated the risk of AMR transmission from a farm to nearby residential areas by examining the overall occurrence of endotoxins, antibiotic resistance genes (ARGs), and mobile genetic elements (MGEs) in the air of a cattle farm. We assessed various factors, including the season and year, day and nighttime, and different locations within the farm building and its vicinity. The most abundant ARGs detected were tetW, aadA1, and sul2, genes that encode for resistances towards antibiotics commonly used in veterinary medicine. While there was a clear concentration gradient for endotoxin from the middle of the farm building to the outside areas, the abundance of ARGs and MGEs was relatively uniform among all locations within the farm and its vicinity. This suggests that endotoxins preferentially accumulated in the coarse particle fraction, which deposited quickly, as opposed to the ARGs and MGEs, which might concentrate in the fine particle fraction and remain longer in the aerosol phase. The occurrence of the same genes found in the air samples and in the manure indicated that ARGs and MGEs in the air mostly originated from the cows, continuously being released from the manure to the air. Although our atmospheric dispersion model indicated a relatively low risk for nearby residential areas, farm workers might be at greater risk of getting infected with resistant bacteria and experiencing overall respiratory tract issues due to continuous exposure to elevated concentrations of endotoxins, ARGs and MGEs in the air of the farm.

Creating an Amyloid 'Kaleidoscope' Using Short Iodinated Peptides

Amyloid fibrils formed by peptides with different sequences exhibit diversified morphologies, material properties and activities, making them valuable for developing functional bionanomaterials. However, the molecular understanding underlying the structural diversity of peptide fibrillar assembly at atomic level is still lacking. In this study, by using cryogenic electron microscopy, we first revealed the structural basis underlying the highly reversible assembly of 1 GFGGNDNFG9 (referred to as hnRAC1) peptide fibril. Furthermore, by installing iodine at different sites of hnRAC1, we generated a collection of peptide fibrils with distinct thermostability. By determining the atomic structures of the iodinated fibrils, we discovered that iodination at different sites of the peptide facilitates the formation of diverse halogen bonds and triggers the assembly of entirely different structures of iodinated fibrils. Finally, based on this structural knowledge, we designed an iodinated peptide that assembles into new atomic structures of fibrils, exhibiting superior thermostability, that aligned with our design. Our work provides an in-depth understanding of the atomic-level processes underlying the formation of diverse peptide fibril structures, and paves the way for creating an amyloid "kaleidoscope" by employing various modifications and peptide sequences to fine-tune the atomic structure and properties of fibrillar nanostructures.

Structural mechanism for specific binding of chemical compounds to amyloid fibrils

Amyloid fibril is an important pharmaceutical target for diagnostic and therapeutic treatment of neurodegenerative diseases. However, rational design of chemical compounds that interact with amyloid fibrils is unachievable due to the lack of mechanistic understanding of the ligand-fibril interaction. Here we used cryoelectron microscopy to survey the amyloid fibril-binding mechanism of a series of compounds including classic dyes, (pre)clinical imaging tracers and newly identified binders from high-throughput screening. We obtained clear densities of several compounds in complex with an α-synuclein fibril. These structures unveil the basic mechanism of the ligand-fibril interaction, which exhibits remarkable difference from the canonical ligand-protein interaction. In addition, we discovered a druggable pocket that is also conserved in the ex vivo α-synuclein fibrils from multiple system atrophy. Collectively, these findings expand our knowledge of protein-ligand interaction in the amyloid fibril state, which will enable rational design of amyloid binders in a medicinally beneficial way.

Acetylation encodes Tau aggregation

Post-translational modifications profoundly influence amyloid assembly. In this issue of Structure, Li et al. unravel the underlying mechanism by which specific lysine acetylation patterns facilitate fibril formation of Tau segments. Their cryo-electron microscopy structure further elucidates how acetyl groups act as stabilizers within the architecture of Tau fibrils.

Development of an α-synuclein positron emission tomography tracer for imaging synucleinopathies

Synucleinopathies are characterized by the accumulation of α-synuclein (α-Syn) aggregates in the brain. Positron emission tomography (PET) imaging of synucleinopathies requires radiopharmaceuticals that selectively bind α-Syn deposits. We report the identification of a brain permeable and rapid washout PET tracer [18F]-F0502B, which shows high binding affinity for α-Syn, but not for Aβ or Tau fibrils, and preferential binding to α-Syn aggregates in the brain sections. Employing several cycles of counter screenings with in vitro fibrils, intraneuronal aggregates, and neurodegenerative disease brain sections from several mice models and human subjects, [18F]-F0502B images α-Syn deposits in the brains of mouse and non-human primate PD models. We further determined the atomic structure of the α-Syn fibril-F0502B complex by cryo-EM and revealed parallel diagonal stacking of F0502B on the fibril surface through an intense noncovalent bonding network via inter-ligand interactions. Therefore, [18F]-F0502B is a promising lead compound for imaging aggregated α-Syn in synucleinopathies.

Culturing partial-denitrification (PD) granules in continuous flow reactor with waste sludge as inoculum: Performance, granular sludge characteristics and microbial community

Partial denitrification granular sludge (PDGS) can provide long-term stable nitrite for anaerobic ammonia oxidation (anammox). The cultivation of ordinary activated sludge from wastewater treatment plants into PDGS can further promote the application of PD in practical engineering. In this study, the feasibility of fast start-up of PDGS was explored by inoculating waste sludge in up-flow anaerobic sludge blanket (UASB) reactor with synergistic control of nitrogen load rate (NLR, 0.05-0.65 kg N/m³/d) and electron donor starvation (EDS) (240-168 mg L^-1), and system performance, particle characteristics and microbial structure were studied. The results showed that PD-UASB started successfully within 48 days, the average nitrite accumulation rate (NTR) and nitrate removal ratio (NRR) reached 79.6% and 82.5% after successful initiation, accompanied by high abundance of PD bacteria (Thauera, Pseudomonas, unclassflied commamonadaceae and Limnobacter) (25.3%). The increase of PD activity, and the difference between nitrate reductase (NAR) and nitrite reductase (NIR) contributed to nitrite production. Besides, the sludge shifted from flocculated (≤0.5 mm, 95.37%) to granulated state (0.5-2mm, 64.74%), which could be due to the increase of extracellular polymers (EPS) (especially T-EPS) and metabolism of specific microorganisms (Bacteroidota and Chloroflexi, 19.92%). Good sludge granulation promoted the settleability of PD (the SVI₅ was 47.248mL/ g. ss after successful start-up). In summary, good PD sludge granulation process could be achieved in a short time by synergistically controlling NLR and EDS.

Rational design of functional amyloid fibrillar assemblies

Amyloid fibrillar assemblies, originally identified as pathological entities in neurodegenerative diseases, have been widely adopted by various proteins to fulfill diverse biological functions in living organisms. Due to their unique features, such as hierarchical assembly, exceptional mechanical properties, environmental stability, and self-healing properties, amyloid fibrillar assemblies have been employed as functional materials in numerous applications. Recently, with the rapid advancement in synthetic biology and structural biology tools, new trends in the functional design of amyloid fibrillar assemblies have begun to emerge. In this review, we provide a comprehensive overview of the design principles for functional amyloid fibrillar assemblies from an engineering perspective, as well as through the lens of structural insights. Initially, we introduce the fundamental structural configurations of amyloid assemblies and highlight the functions of representative examples. We then focus on the underlying design principles of two prevalent strategies for the design of functional amyloid fibrillar assemblies: (1) introducing new functions via protein modular design and/or hybridization, with typical applications encompassing catalysis, virus disinfection, biomimetic mineralization, bio-imaging, and biotherapy; and (2) dynamically regulating living amyloid fibrillar assemblies using synthetic gene circuits, with typical applications in pattern formation, leakage repair, and pressure sensing. Next, we summarize how breakthroughs in characterization techniques have contributed to unveiling the structural polymorphism of amyloid fibrils at the atomic level, and further clarifying the highly diverse regulation mechanisms of amyloid fibrillar assembly and disassembly fine-tuned by various factors. The structural knowledge may significantly aid in the structure-guided design of amyloid fibrillar assemblies with diverse bio-activities and adjustable regulatory properties. Finally, we envision that a new trend in functional amyloid design may emerge by integrating structural tunability, synthetic biology and artificial intelligence.

[The efficacy and safety of Bruton tyrosine kinase inhibitors as monotherapy in the treatment of newly diagnosed patients with Waldenström macroglobulinemia]

Objective: To investigate the efficacy and safety of Bruton tyrosine kinase inhibitors (BTKi) ibrutinib or zanubrutinib monotherapy in newly diagnosed patients with Waldenström macroglobulinemia (WM) . Methods: The efficacy and adverse effects of 58 patients with newly diagnosed WM receiving BTKi monotherapy in Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine were analyzed retrospectively from January 2018 to August 2022. Results: The response of 55 patients may be examined. Forty patients received ibrutinib monotherapy for a median of 15 months, with an overall response rate (ORR) of 85%, a main remission rate (MRR) of 70%, and a very good partial remission (VGPR) rate of 10%. Fifteen patients received zanubrutinib monotherapy for a median of 13 months, with an ORR of 93%, an MRR of 73%, and a VGPR rate of 0%. For various reasons, 10 patients were converted from ibrutinib to zanubrutinib. Ibrutinib treatment lasted an average of 7.5 months before conversion. The median duration of zanubrutinib therapy after conversion was 3.5 months. The ORRs before and after conversion were 90% and 100%, MRRs were 80% and 80%, and VGPR rates were 10% and 50%, respectively. After a median of 16 months, the 24-month progression-free survival (PFS) rate of patients who received both BTKi was 86%. PFS did not differ statistically across individuals with low, medium, and high-risk ISS scores (P=0.998). All of the patients survived. The most common side effects of BTKi were neutropenia and thrombocytopenia, which occurred in 12% and 10% of all patients, respectively. Ibrutinib accounts for 5% of atrial fibrillation, and zanubrutinib has a 7% risk of bleeding. Conclusions: In treating WM, ibrutinib or zanubrutinib provides good efficacy and tolerable adverse effects.

The value of microbiology rapid on-site evaluation of sepsis caused by pulmonary infection

OBJECTIVE

This study aims to evaluate the value of microbial rapid on-site evaluation (M-ROSE) of sepsis, and septic shock caused by pulmonary infection.

PATIENTS AND METHODS

Thirty-six patients with sepsis and septic shock due to hospital-acquired pneumonia were analyzed. Accuracy and time were compared with M-ROSE, traditional culture, and next-generation sequencing (NGS).

RESULTS

A total of 48 strains of bacteria and 8 strains of fungi were detected by bronchoscopy in 36 patients. The accuracy rate of bacteria and fungi was 95.8% and 100%, respectively. M-ROSE took an average of 0.34±0.01 hours, much faster than NGS (22h±0.01 h, p<0.0001) and traditional culture time (67.50±0.91 h, p<0.0001).

CONCLUSIONS

M-ROSE may quickly identify common bacteria and fungi, so it may be a useful method for the etiological diagnosis of sepsis and septic shock caused by pulmonary infection.

HMGB1 acts as an agent of host defense at the gut mucosal barrier

Mucosal barriers provide the first line of defense between internal body surfaces and microbial threats from the outside world. ¹ In the colon, the barrier consists of two layers of mucus and a single layer of tightly interconnected epithelial cells supported by connective tissue and immune cells. ² Microbes colonize the loose, outer layer of colonic mucus, but are essentially excluded from the tight, epithelial-associated layer by host defenses. ³ The amount and composition of the mucus is calibrated based on microbial signals and loss of even a single component of this mixture can destabilize microbial biogeography and increase the risk of disease. ^4-7 However, the specific components of mucus, their molecular microbial targets, and how they work to contain the gut microbiota are still largely unknown. Here we show that high mobility group box 1 (HMGB1), the prototypical damage-associated molecular pattern molecule (DAMP), acts as an agent of host mucosal defense in the colon. HMGB1 in colonic mucus targets an evolutionarily conserved amino acid sequence found in bacterial adhesins, including the well-characterized Enterobacteriaceae adhesin FimH. HMGB1 aggregates bacteria and blocks adhesin-carbohydrate interactions, inhibiting invasion through colonic mucus and adhesion to host cells. Exposure to HMGB1 also suppresses bacterial expression of FimH. In ulcerative colitis, HMGB1 mucosal defense is compromised, leading to tissue-adherent bacteria expressing FimH. Our results demonstrate a new, physiologic role for extracellular HMGB1 that refines its functions as a DAMP to include direct, virulence limiting effects on bacteria. The amino acid sequence targeted by HMGB1 appears to be broadly utilized by bacterial adhesins, critical for virulence, and differentially expressed by bacteria in commensal versus pathogenic states. These characteristics suggest that this amino acid sequence is a novel microbial virulence determinant and could be used to develop new approaches to diagnosis and treatment of bacterial disease that precisely identify and target virulent microbes.

Bacterial antibiotic resistance among cancer inpatients in China: 2016-20

BACKGROUND

The incidence of infections among cancer patients is as high as 23.2-33.2% in China. However, the lack of information and data on the number of antibiotics used by cancer patients is an obstacle to implementing antibiotic management plans.

AIM

This study aimed to investigate bacterial infections and antibiotic resistance in Chinese cancer patients to provide a reference for the rational use of antibiotics.

DESIGN

This was a 5-year retrospective study on the antibiotic resistance of cancer patients.

METHODS

In this 5-year surveillance study, we collected bacterial and antibiotic resistance data from 20 provincial cancer diagnosis and treatment centers and three specialized cancer hospitals in China. We analyzed the resistance of common bacteria to antibiotics, compared to common clinical drug-resistant bacteria, evaluated the evolution of critical drug-resistant bacteria and conducted data analysis.

FINDINGS

Between 2016 and 2020, 216 219 bacterial strains were clinically isolated. The resistance trend of Escherichia coli and Klebsiella pneumoniae to amikacin, ciprofloxacin, cefotaxime, piperacillin/tazobactam and imipenem was relatively stable and did not significantly increase over time. The resistance of Pseudomonas aeruginosa strains to all antibiotics tested, including imipenem and meropenem, decreased over time. In contrast, the resistance of Acinetobacter baumannii strains to carbapenems increased from 4.7% to 14.7%. Methicillin-resistant Staphylococcus aureus (MRSA) significantly decreased from 65.2% in 2016 to 48.9% in 2020.

CONCLUSIONS

The bacterial prevalence and antibiotic resistance rates of E. coli, K. pneumoniae, P. aeruginosa, A. baumannii, S. aureus and MRSA were significantly lower than the national average.

[Surgical skills and precautions of pelvic exenteration combined with pelvic wall resection]

The treatment of locally advanced rectal cancer (LARC) or locally recurrent rectal cancer (LRRC) has been a difficulty and challenge in the field of advanced rectal cancer, while pelvic exenteration (PE), as an important way to potentially achieve radical treatment of LARC and LRRC, has been shown to significantly improve the long-term prognosis of patients. The implementation of PE surgery requires precise assessment of the extent of invasion of LARC or LRRC and adequate preoperative preparation through multidisciplinary consultation before surgery. The lateral pelvis involves numerous tissues, blood vessels, and nerves, and resection is most difficult, and the ureteral and Marcille triangle approaches are recommended; while the supine transabdominal approach combined with intraoperative change to the prone jacket position facilitates adequate exposure of the surgical field and enables precise overall resection of the bony pelvis and pelvic floor muscle groups invaded by the tumor. Empty pelvic syndrome has always been an major problem to be solved during PE. The application of extracellular matrix biological mesh to reconstruct pelvic floor defects and isolate the abdominopelvic cavity is expected to reduce postoperative pelvic floor related complications. Reconstruction of the urinary system and important vessels after PE is essential, and the selection of appropriate reconstruction methods helps to improve the patient's postoperative quality of life, while more new methods are also being continuously explored.

[Clinical study of using basement membrane biological products in pelvic floor reconstruction during pelvic exenteration]

Objective: To investigate the value of reconstruction of pelvic floor with biological products to prevent and treat empty pelvic syndrome after pelvic exenteration (PE) for locally advanced or recurrent rectal cancer. Methods: This was a descriptive study of data of 56 patients with locally advanced or locally recurrent rectal cancer without or with limited extra-pelvic metastases who had undergone PE and pelvic floor reconstruction using basement membrane biologic products to separate the abdominal and pelvic cavities in the Department of Anorectal Surgery of the Second Affiliated Hospital of Naval Military Medical University from November 2021 to May 2022. The extent of surgery was divided into two categories: mainly inside the pelvis (41 patients) and including pelvic wall resection (15 patients). In all procedures, basement membrane biologic products were used to reconstruct the pelvic floor and separate the abdominal and pelvic cavities. The procedures included a transperitoneal approach, in which biologic products were used to cover the retroperitoneal defect and the pelvic entrance from the Treitz ligament to the sacral promontory and sutured to the lateral peritoneum, the peritoneal margin of the retained organs in the anterior pelvis, or the pubic arch and pubic symphysis; and a sacrococcygeal approach in which biologic products were used to reconstruct the defect in the pelvic muscle-sacral plane. Variables assessed included patients' baseline information (including sex, age, history of preoperative radiotherapy, recurrence or primary, and extra-pelvic metastases), surgery-related variables (including extent of organ resection, operative time, intraoperative bleeding, and tissue restoration), post-operative recovery (time to recovery of bowel function and time to recovery from empty pelvic syndrome), complications, and findings on follow-up. Postoperative complications were graded using the Clavien-Dindo classification. Results: The median age of the 41 patients whose surgery was mainly inside the pelvis was 57 (31-82) years. The patients comprised 25 men and 16 women. Of these 41 patients, 23 had locally advanced disease and 18 had locally recurrent disease; 32 had a history of chemotherapy/immunotherapy/targeted therapy and 24 of radiation therapy. Among these patients, the median operative time, median intraoperative bleeding, median time to recovery of bowel function, and median time to resolution of empty pelvic syndrome were 440 (240-1020) minutes, 650 (200-4000) ml, 3 (1-9) days, and 14 (5-105) days, respectively. As for postoperative complications, 37 patients had Clavien-Dindo < grade III and four had ≥ grade III complications. One patient died of multiple organ failure 7 days after surgery, two underwent second surgeries because of massive bleeding from their pelvic floor wounds, and one was successfully resuscitated from respiratory failure. In contrast, the median age of the 15 patients whose procedure included combined pelvic and pelvic wall resection was 61 (43-76) years, they comprised eight men and seven women, four had locally advanced disease and 11 had locally recurrent disease. All had a history of chemotherapy/ immunotherapy and 13 had a history of radiation therapy. The median operative time, median intraoperative bleeding, median time to recovery of bowel function, and median time to relief of empty pelvic syndrome were 600 (360-960) minutes, 1600 (400-4000) ml, 3 (2-7) days, and 68 (7-120) days, respectively, in this subgroup of patients. Twelve of these patients had Clavien-Dindo < grade III and three had ≥ grade III postoperative complications. Follow-up was until 31 October 2022 or death; the median follow-up time was 9 (5-12) months. One patient in this group died 3 months after surgery because of rapid tumor progression. The remaining 54 patients have survived to date and no local recurrences have been detected at the surgical site. Conclusion: The use of basement membrane biologic products for pelvic floor reconstruction and separation of the abdominal and pelvic cavities during PE for locally advanced or recurrent rectal cancer is safe, effective, and feasible. It improves the perioperative safety of PE and warrants more implementation.

Conformational Dynamics of an α-Synuclein Fibril upon Receptor Binding Revealed by Insensitive Nuclei Enhanced by Polarization Transfer-Based Solid-State Nuclear Magnetic Resonance and Cryo-Electron Microscopy

Many amyloid fibrils associated with neurodegenerative diseases consist of an ordered fibril core (FC) and disordered terminal regions (TRs). The former represents a stable scaffold, while the latter is rather active in binding with various partners. Current structural studies mainly focus on the ordered FC since the high flexibility of TRs hinders structural characterization. Here, by combining insensitive nuclei enhanced by polarization transfer-based ¹H-detected solid-state NMR and cryo-EM, we explored the intact structure of an α-syn fibril including both FC and TRs and further studied the conformational dynamics of the fibril upon binding to lymphocyte activation gene 3 (LAG3)─a cell surface receptor that is involved in α-syn fibril transmission in brains. We found that both the N- and C-TRs of α-syn are disordered in free fibrils featuring similar conformation ensembles as those in soluble monomers. While in the presence of the D1 domain of LAG3 (L3D1), the C-TR directly binds to L3D1, meanwhile the N-TR folds into a β-strand and further integrates with the FC, which leads to alteration of the overall fibril structure and surface property. Our work reveals synergistic conformational transition of the intrinsically disordered TRs of α-syn, which sheds light on mechanistic understanding of the essential role of TRs in regulating the structure and pathology of amyloid fibrils.

Structural Insights of Fe3+ Induced α-synuclein Fibrillation in Parkinson's Disease

Amyloid aggregation of α-synuclein (α-syn) in Lewy bodies (LBs) is the pathological hallmark of Parkinson's disease (PD). Iron, especially Fe³⁺, is accumulated in substantia nigra of PD patients and co-deposited with α-syn in LBs. However, how Fe³⁺ modulates α-syn fibrillation at molecular level remains unclear. In this study, we found that Fe³⁺ can promote α-syn fibrillation at low concentration while inhibit its fibrillation at high concentration. NMR titration study shows poor interaction between α-syn monomer and Fe³⁺. Instead, we found that Fe³⁺ binds to α-syn fibrils. By using cryo-electron microscopy (cryo-EM), we further determined the atomic structure of α-syn fibril in complex with Fe³⁺ at the resolution of 2.7 Å. Strikingly, two extra electron densities adjacent to His50 and Glu57 were observed as putative binding sites of Fe³⁺ and water molecules, suggesting that Fe³⁺ binds to the negative cleft of the fibril and stabilizes the fibril structure for promoting α-syn aggregation. Further mutagenesis study shows mutation of His50 abolishes the Fe³⁺-facilitated fibrillation of α-syn. Our work illuminates the structural basis of the interaction of Fe³⁺ and α-syn in both monomeric and fibrillar forms, and sheds light on understanding the pathological role of Fe³⁺ in α-syn aggregation in PD.

[Effects of extramedullary disease on patients with newly diagnosed multiple myeloma]

Objective: To summarize the characteristics of patients with newly diagnosed multiple myeloma (NDMM) admitted at Ruijin Hospital affiliated to Shanghai Jiaotong University School of Medicine. We compared the clinical characteristics and prognoses among patients with non-extramedullary disease (EMD), bone-related extramedullary (EM-B) disease, and extraosseous extramedullary (EM-E) disease and further explored the effects of autologous hematopoietic stem cell transplantation (ASCT) for EMD. Methods: From January 2015 to January 2022, data of 114 patients (22%) with EMD out of 515 patients with NDMM were retrospectively analyzed; 91 (18%) and 23 (4%) patients comprised the EM-B and EM-E groups, respectively. The clinical characteristics of patients in all groups were compared with the Chi-square test. Progression-free survival (PFS) and overall survival (OS) of patients were analyzed by the Kaplan-Meier method. Independent prognostic factors were determined using multivariate Cox proportional hazard model. Results: There were no significant differences in age, gender, ISS stage, light chain, creatinine clearance, cytogenetic risk, 17p deletion, ASCT, and induction regimens among the three groups. Overall, 13% of EM-E patients had IgD-type M protein, which was significantly higher than that in EM-B patients (P=0.021). The median PFS of patients in the non-EMD, EM-B, and EM-E groups was 27.4, 23.1, and 14.0 months; the median OS was not reached, 76.8 months, and 25.6 months, respectively. The PFS (vs non-EMD, P=0.004; vs EM-B, P=0.036) and OS (vs non-EMD, P<0.001; vs EM-B, P=0.002) were significantly worse in patients with EM-E, while those were not significantly different between patients with EM-B and those with non-EMD. In the multivariate analysis, EM-E was an independent prognostic factor for OS in patients with NDMM (HR=8.779, P<0.001) and negatively impacted PFS (HR=1.874, P=0.050). In those who did not undergo ASCT, patients with EM-B had significantly worse OS than those with non-EMD (median 76.8 months vs. not reached, P=0.029). However, no significant difference was observed in the PFS and OS of patients with EM-B and those with non-EMD who underwent ASCT. Conclusions: Compared to patients with either non-EMD or EM-B, those with EM-E had the worst prognosis. EM-E was an independent risk factor for OS in patients with NDMM. ASCT can overcome the poor prognosis of EM-B.

Pembrolizumab versus cetuximab concurrent with radiotherapy in patients with locally advanced squamous cell carcinoma of head and neck unfit for cisplatin (GORTEC 2015-01 PembroRad): a multicenter, randomized, phase II trial

BACKGROUND

To evaluate potential synergistic effect of pembrolizumab with radiotherapy (RT) compared with a standard-of-care (SOC) cetuximab-RT in patients with locally advanced-squamous cell carcinoma of head and neck (LA-SCCHN).

PATIENTS AND METHODS

Patients with nonoperated stage III-IV SCC of oral cavity, oropharynx, hypopharynx, and larynx and unfit for receiving high-dose cisplatin were enrolled. Patients received once-daily RT up to 69.96 Gy in 33 fractions with weekly cetuximab (cetuximab-RT arm) or 200 mg Q3W pembrolizumab during RT (pembrolizumab-RT arm). The primary endpoint was locoregional control (LRC) rate 15 months after RT. To detect a difference between arms of 60%-80% in 15-month LRC, inclusion of 66 patients per arm was required to achieve a power of at least 0.85 at two-sided significance level of 0.20.

RESULTS

Between May 2016 and October 2017, 133 patients were randomized to cetuximab-RT (n = 66) and pembrolizumab-RT (n = 67). Two patients (one in each arm) were not included in the analysis (a consent withdrawal and a progression before treatment start). The median age was 65 years (interquartile range 60-70 years), 92% were smokers, 60% were oropharynx (46% of oropharynx with p16+) and 75% were stage IV. Median follow-up was 25 months in both arms. The 15-month LRC rate was 59% with cetuximab-RT and 60% with pembrolizumab-RT ]odds ratio 1.05, 95% confidence interval (CI) 0.43-2.59; P = 0.91]. There was no significant difference between arms for progression-free survival (hazard ratio 0.85, 95% CI 0.55-1.32; P = 0.47) and for overall survival (hazard ratio 0.83, 95% CI 0.49-1.40; P = 0.49). Toxicity was lower in the pembrolizumab-RT arm than in the cetuximab-RT arm: 74% versus 92% patients with at least one grade ≥3 adverse events (P = 0.006), mainly due to mucositis, radiodermatitis, and rash.

CONCLUSION

Compared with the SOC cetuximab-RT, pembrolizumab concomitant with RT did not improve the tumor control and survival but appeared less toxic in unfit patients with LA-SCCHN.

Starting up anammox system with high efficiency nitrogen removal at low temperatures: Performance optimization, sludge characterization and microbial community analysis

Anaerobic ammonia oxidation (anammox) has potential advantages for nitrogen removal when operating at medium temperatures, but the increased operation costs of heating limit its application. It would be advantageous to start and operate anammox at low temperatures, the feasibility of which was studied here on a lab scale. Two identical expanded granular sludge bed (EGSB) reactors were inoculated at 35 ± 1 °C (A_med) and 15 ± 3 °C (A_low). Results showed that anammox was successful after 138 d for A_low, only 7 d longer than A_med. Stable operation to 194 d in A_low, the nitrogen loading rate (NLR) increased to 1.01 kg m^-3·d^-1, giving a high nitrogen removal efficiency (NRE) of 85%, which was only slightly lower than that of A_med (90%). More extracellular polymeric substance (EPS) was produced by the microbes of A_low compared to A_med, which prevented anaerobic ammonia oxidizing bacteria (AnAOB) against low temperature stress. Microbial community revealed presence of Candidatus Jettenia in A_med with relative abundance 7.4%, while the "cold-tolerant" Candidatus Kuenenia with 4% was the dominant anammox bacteria in A_low. The anammox granules adapted well to low temperatures and demonstrated high efficiency in anammox process without heating. Therefore, constructing an energy-saving and cost-effective anammox system in high latitudes or high altitudes can be considered.

[Potential application of improved hard tissue section technique in the clinical pathological diagnosis of bone and bone marrow]

Objective: To discuss the application value of hard tissue section in the clinicopathology diagnosis. Methods: From March 2021 to December 2021, bone slices of 19 patients (1 patient with osteochondroma, 2 patients with chondrosarcoma, 4 patients with osteosarcoma, 2 patients with fibrous dysplasia, 2 patients with bone metastasis from thyroid papillary carcinoma, 2 patients with osteomyelitis, 4 patients with giant cell tumor of bone, 2 patients with Ewing sarcoma) and 16 hemopathy patients were collected from the Department of Pathology, Shanghai Sixth People's Hospital. Of the osteopathy patients, there were 14 male and 5 female with a median age of 31 (10-66) years. Meanwhile, there were 7 male and 9 female with a median age of 28 (16-65) years among these hemopathy patients. Thirty-five cases were treated with modified hard tissue slicing technique and paraffin embedding technique, respectively. The advantages and disadvantages of the two methods for clinical diagnosis of bone disease were compared by Hematoxylin-Eosin staining (H&E staining), immunohistochemical staining (IHC), fluorescence in situ hybridization (FISH) and Sanger sequencing. Results: The improved resin-embedded method showed better histological morphology and cell structure. Besides, the expression of Ki67, SATB2, CD34, SMA, CD68,MPO,CD4 and CD33 in immunohistochemical staining in bone tissues which were embedded in resin were more clear in the accurate positive localization than those using paraffin-embedded. MDM2 of FISH exhibited a higher fluorescence intensity and more accurate location. Meanwhile, both methods treated with Sanger sequencing met the requirements of DNA purity and mutation detection. Conclusion: The improved hard tissue section method is simple and short time-consuming, which is suitable for optimizing the clinical bone and bone marrow pathological diagnosis process.

Heparin induces α-synuclein to form new fibril polymorphs with attenuated neuropathology

α-Synuclein (α-syn), as a primary pathogenic protein in Parkinson’s disease (PD) and other synucleinopathies, exhibits a high potential to form polymorphic fibrils. Chemical ligands have been found to involve in the assembly of α-syn fibrils in patients’ brains. However, how ligands influence the fibril polymorphism remains vague. Here, we report the near-atomic structures of α-syn fibrils in complex with heparin, a representative glycosaminoglycan (GAG), determined by cryo-electron microscopy (cryo-EM). The structures demonstrate that the presence of heparin completely alters the fibril assembly via rearranging the charge interactions of α-syn both at the intramolecular and the inter-protofilamental levels, which leads to the generation of four fibril polymorphs. Remarkably, in one of the fibril polymorphs, α-syn folds into a distinctive conformation that has not been observed previously. Moreover, the heparin-α-syn complex fibrils exhibit diminished neuropathology in primary neurons. Our work provides the structural mechanism for how heparin determines the assembly of α-syn fibrils, and emphasizes the important role of biological polymers in the conformational selection and neuropathology regulation of amyloid fibrils.

Subtle change of fibrillation condition leads to substantial alteration of recombinant Tau fibril structure

In vitro assembly of amyloid fibrils that recapitulate those in human brains is very useful for fundamental and applied research on the amyloid formation, pathology, and clinical detection. Recent success in the assembly of Tau fibrils in vitro enables the recapitulation of the paired helical filament (PHF) of Tau extracted from brains of patients with Alzheimer's disease (AD). However, following the protocol, we observed that Tau constructs including 297-391 and a mixture of 266-391 (3R)/297-391, which are expected to predominantly form PHF-like fibrils, form highly heterogeneous fibrils instead. Moreover, the seemingly PHF-like fibril formed by Tau 297-391 exhibits a distinctive atomic structure with a spindle-like fold, that is neither PHF-like or similar to any known Tau fibril structures revealed by cryo-electron microscopy (cryo-EM). Our work highlights the high sensitivity of amyloid fibril formation to subtle conditional changes and suggests high-resolution structural characterization to in vitro assembled fibrils prior to further laboratory use.

[Clinical characteristics and prognosis of patients with newly-diagnosed multiple myeloma with t(11;14)]

Objective: To explore the clinical characteristics and prognosis of multiple myeloma (MM) patients with t(11;14). Methods: The clinical data of patients newly diagnosed with MM with t(11;14), which confirmed by fluorescence in situ hybridization (FISH), from January 1, 2016 to May 31, 2021 in Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine was retrospectively collected. A total of 45 patients were included. Bortezomib based induction therapy were given to 88.9% (40/45) patients, while 11.1% (5/45) received Imids-based therapy. Fourteen patients underwent the autologous hematopoietic stem cell transplantation (AHSCT). The clinical characteristics, overall response rate (ORR), progression free survival (PFS), overall survival (OS) and risk factors affecting survival were analyzed. Results: The average age of patients were (58.8±9.6) years, and 62.2%(28/45)were male. A relatively high incidence of bone lesion 82.2%(37/45)was observed. After 4 cycles induction therapy, the ORR was 66.7% (30/45), and ≥very good partial response (VGPR) was 31.3% (14/45). The rate of ≥VGPR increased to 92.9% (13/14) after AHSCT. The follow-up time [M(Q₁,Q₃)] was 27(20,42)months. The PFS was 34 (95%CI: 23-45) months, the median OS was 44 (95%CI:33-51) months. Median PFS were 48 (only 3 cases of progressive disease, CI not available) months and 24 (95%CI:13-35) months in the transplantation group and non-transplant group respectively (P=0.115). Median OS were 60 (only 1 case of death, CI not available) months and 48 (95%CI:22-74) months in the transplantation group and non-transplantation group, respectively (P=0.238). Cox regression analysis indicated that the number of plasma cell ≥50% in bone marrow and CD20 expression on myeloma cells were the risk factors for PFS[OR=3.272,95%CI:1.167-9.170,P=0.024;OR=3.480,95%CI:1.082-11.234,P=0.036]. No significant effective factor on OS was found. Conclusions: For multiple myeloma patient with t(11;14), the response rate with novel agents induction therapy is not high, but autologous stem cell transplantation can deepen remission. The high burden of bone marrow plasma cells and the expression of CD20 may be associated with the poor prognosis.

Assembly of Ultralong Hydroxyapatite Nanowires into Enamel-like Materials

To develop dental restorative materials with enamel-like structures, ultralong hydroxyapatite (HA) nanowires were synthesized by a hydrothermal method, followed by functionalization with 3-methacryloxypropyltrimethoxysilane (KH-570). The mixture of HA nanowires, KH-570, and light initiator was stirred and centrifuged. The precipitate was vacuum filtered to remove excessive KH-570 and then pressured under cold isostatic pressing (10 MPa × 24 h). Finally, the block was polymerized by lighting. Scanning electron microscopy and transmission electron microscopy showed that HA nanowires with aspect ratios >1,000 were assembled into enamel rod-like microstructures and evenly dispersed in the polymerized KH-570 silane matrix to form enamel-like structures. Thermogravimetric analysis demonstrated that the content of HA nanowires reached 72 wt% in the composite. The enamel-like composite showed a similar hardness, frictional property, and acid-etching property to those of enamel and a comparable or even better diametral tensile strength and compressive strength than some commercial composite resins in mechanical tests in vitro. In addition, the enamel-like composite had good cytocompatibility. Such enamel-like composites may have the potential to be used in biomimetic tooth restorations in the future.

Treatment of high-concentration phosphorus wastewater based on foamed concrete

Phosphorus is a nonrenewable resource, and the recovery of phosphorus from wastewater containing high concentrations of phosphorus is of great importance. In this work, a novel method for highly efficient treatment of high-concentration phosphorus-containing wastewater (50 mg/L, 100 mg/L and 150 mg/L) with low energy consumption was developed by using the block waste foam concrete (FC) as a potential phosphorus recovery material. The results showed that acid leaching significantly improved the accumulation efficiency of phosphorus in calcium hydroxyphosphate (HAP) via accelerating the release of calcium in wastewater. The recovery rate of phosphorus could reach 99.0% under the pH value of 9.0 at 25 °C, using 2.0 g FC. It was also found that the microporous structure of the surface of FC provided the adsorption sites for phosphorus, resulting in the adsorption rate in different concentrations of phosphorus-containing wastewater up to 14.5%. It indicated that FC achieved the recovery of phosphorus from high-concentration phosphorus-containing wastewater by coupling HAP crystallization and physical adsorption to polyphosphorus.

[Exploring the detection of MYD88 mutation in patients with Waldenström macroglobulinemia by different methods and specimens]

Objective: To improve the positivity rate and accuracy of MYD88 mutation detection in patients with Waldenström macroglobulinemia (WM) . Methods: MYD88 mutation status was retrospectively evaluated in 66 patients diagnosed with WM in Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from June 2017 to June 2021. The positivity rate and accuracy of the different methods and specimens for MYD88 mutation detection were analyzed. Results: MYD88 mutations were detected in 51 of 66 patients with WM, with an overall positivity rate of 77%. The positivity rate of the next-generation sequencing (NGS) or allele-specific polymerase chain reaction (AS-PCR) was significantly higher than that of the first-generation Sanger sequencing (84% vs 71% vs 46%, P<0.05) . For the different specimens, the positivity rate for the lymph nodes or bone marrow was significantly higher than that of peripheral blood (79% vs 84% vs 52%, P<0.05) . The positivity rate of the MYD88 mutation in the lymph nodes, bone marrow, and peripheral blood determined by NGS was 86%, 90%, and 67%, respectively. The positivity rate in the lymph nodes, bone marrow, and peripheral blood detected by AS-PCR was 78%, 81%, and 53%, respectively. Thirty-nine patients with WM underwent ≥ 2 MYD88 mutation detections. The final MYD88 mutational status for each patient was used as the standard to determine the accuracy of the different methods and in different specimens. The accuracy of MYD88 mutation detection in the lymph nodes (n=18) and bone marrow (n=13) by NGS was significantly higher than that in the peripheral blood (n=4) (100% vs 100% vs 75%, P<0.05) . There was no statistically significant difference in the accuracy of MYD88 mutation detection by AS-PCR in the lymph nodes (n=15) , bone marrow (n=11) , or peripheral blood (n=16) (93% vs 91% vs 88%, P>0.05) . Conclusions: In the detection of the MYD88 mutation in patients diagnosed with WM, NGS or AS-PCR is more sensitive than Sanger sequencing. Lymph nodes and bone marrow specimens are better than peripheral blood specimens.

Molecular structure of an amyloid fibril formed by FUS low-complexity domain

FUS is a multifunctional nuclear protein which undergoes liquid–liquid phase separation in response to stress and DNA damage. Dysregulation of FUS dynamic phase separation leads to formation of pathological fibril closely associated with neurodegenerative diseases such as amyotrophic lateral sclerosis and frontotemporal dementia. In this study, we determined the cryo-EM structure of a cytotoxic fibril formed by the low-complexity (LC) domain of FUS at 2.9 Å resolution. The fibril structure exhibits a new and extensive serpentine fold consisting of three motifs incorporating together via a Tyr triad. FUS LC employs 91 residues to form an enlarged and stable fibril core via hydrophilic interaction and hydrogen bonds, which is distinct from most of previously determined fibrils commonly stabilized by hydrophobic interaction. Our work reveals the structural basis underlying formation of a cytotoxic and thermostable fibril of FUS LC and sheds light on understanding the liquid-to-solid phase transition of FUS in disease.

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Cryo-EM structure of an amyloid fibril formed by FUS low-complexity (LC) domain

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FUS LC forms a novel enlarged and thermostable fibril core (FC) involving 91 residues

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Hydrophilic interaction and hydrogen bonds are essential in FC formation of FUS LC

Measurement of Differential Branching Fractions of Inclusive B→X_{u}ℓ^{+}ν_{ℓ} Decays

The first measurements of differential branching fractions of inclusive semileptonic B→X_{u}ℓ^{+}ν_{ℓ} decays are performed using the full Belle data set of 711  fb^{-1} of integrated luminosity at the ϒ(4S) resonance and for ℓ=e, μ. With the availability of these measurements, new avenues for future shape-function model-independent determinations of the Cabibbo-Kobayashi-Maskawa matrix element |V_{ub}| can be pursued to gain new insights in the existing tension with respect to exclusive determinations. The differential branching fractions are reported as a function of the lepton energy, the four-momentum-transfer squared, light-cone momenta, the hadronic mass, and the hadronic mass squared. They are obtained by subtracting the backgrounds from semileptonic B→X_{c}ℓ^{+}ν_{ℓ} decays and other processes, and corrected for resolution and acceptance effects.

[Biological mesh versus primary closure for pelvic floor reconstruction following extralevator abdominoperineal excision: a meta-analysis]

Objective: To compare the morbidity of perineum-related complication between biological mesh and primary closure in closing pelvic floor defects following extralevator abdominoperineal excision (ELAPE). Methods: A literature search was performed in PubMed, Embase, Cochrane Library, Web of Science, Wanfang database, Chinese National Knowledge Infrastructure, VIP database, and China Biological Medicine database for published clinical researches on perineum-related complications following ELAPE between January 2007 and August 2020. Literature inclusion criteria: (1) study subjects: patients undergoing ELAPE with rectal cancers confirmed by colonoscopy pathological biopsy or surgical pathology; (2) study types: randomized controlled studies or observational studies comparing the postoperative perineum-related complications between the two groups (primary perineal closure and reconstruction with a biological mesh) following ELAPE; (3) intervention measures: biological mesh reconstruction used as the treatment group, and primary closure used as the control group; (4) outcome measures: the included literatures should at least include one of the following postoperative perineal complications: overall perineal wound complications, perineal wound infection, perineal wound dehiscence, perineal hernia, chronic sinus, chronic perineal pain (postoperative 12-month), urinary dysfunction and sexual dysfunction. Literature exclusion criteria: (1) data published repeatedly; (2) study with incomplete or wrong original data and unable to obtain original data. Two reviewers independently performed screening, data extraction and assessment on the quality of included studies. Review Manager 5.3 software was used for meta-analysis. The mobidities of perineum-related complications, including overall perineal wound (infection, dehiscence, hernia, chronic sinus) and perineal chronic pain (postoperative 12-month), were compared between the two pelvic floor reconstruction methods. Finally, publication bias was assessed, and sensitivity analysis was used to evaluate the stability of the results. Results: A total of five studies, including two randomized controlled studies and three observational controlled studies, with 650 patients (399 cases in the biological mesh group and 251 cases in primary closure group) were finally included. Compared with primary closure, biological mesh reconstruction had significantly lower ratio of perineal hernia (RR=0.37, 95%CI: 0.21-0.64, P<0.001). No significant differences in ratios of overall perineal wound complication, perineal wound infection, perineal wound dehiscence, perineal chronic sinus and perineal chronic pain (postoperative 12-month) were found between the two groups (all P>0.05). Conclusion: Compared with primary closure, pelvic floor reconstruction following ELAPE with biological mesh has the advantage of a lower incidence of perineal hernia.

Biological functions and potential therapeutic applications of huntingtin-associated protein 1: progress and prospects

Huntington disease (HD) is a single-gene autosomal dominant inherited neurodegenerative disease caused by a polyglutamine expansion of the protein huntingtin (HTT). Huntingtin-associated protein 1 (HAP1) is the first protein identified as an interacting partner of huntingtin, which is directly associated with HD. HAP1 is mainly expressed in the nervous system and is also found in the endocrine system and digestive system, and then involves in the occurrence of the related endocrine diseases, digestive system diseases, and cancer. Understanding the function of HAP1 could help elucidate the pathogenesis that HTT plays in the disease process. Therefore, this article attempts to summarize the latest research progress of the role of HAP1 and its application for diseases in recent years, aiming to clarify the functions of HAP1 and its interacting proteins, and provide new research ideas and new therapeutic targets for the treatment of cancer and related diseases.

A priori quality assurance using a benchmark case of the randomized phase 2 GORTEC 2014-14 in oligometastatic head and neck cancer patients

PURPOSE

A Benchmark Case (BC) was performed as part of the quality assurance process of the randomized phase 2 GORTEC 2014-14 OMET study, testing the possibility of multisite stereotactic radiation therapy (SBRT) alone in oligometastatic head and neck squamous cell carcinoma (HNSCC) as an alternative to systemic treatment and SBRT.

MATERIAL AND METHODS

Compliance of the investigating centers with the prescription, delineation, planning and evaluation recommendations available in the research protocol was assessed. In addition, classical dosimetric analysis was supplemented by quantitative geometric analysis using conformation indices.

RESULTS

Twenty centers participated in the BC analysis. Among them, four major deviations (MaD) were reported in two centers. Two (10%) centers in MaD had omitted the satellite tumor nodule and secondarily validated after revision. Their respective DICE indexes were 0.37 and 0 and use of extracranial SBRT devices suboptimal There were significant residual heterogeneities between participating centers, including those with a similar SBRT equipment, with impact of plan quality using standard indicators and geometric indices.

CONCLUSION

A priori QA using a BC conditioning the participation of the clinical investigation centers showed deviations from good SBRT practice and led to the exclusion of one out of the twenty participating centers. The majority of centers have demonstrated rigorous compliance with the research protocol. The use of quality indexes adds a complementary approach to improve assessment of plan quality.

[The distribution of peripheral anterior synechiae in patients with primary angle-closure glaucoma]

Objective: To describe the distribution and characteristics of peripheral anterior synechiae (PAS) in patients with primary angle-closure glaucoma (PACG). Methods: Retrospective case study. A total of 285 PACG patients (406 eyes) diagnosed in the Eye Hospital, School of Ophthalmology and Optometry, Wenzhou Medical University from January 2017 to August 2019 were included. They were 102 males and 183 females, with a median age of 67 years old (range, 21 to 95 years old). The PAS range was detected by gonioscopy examination, and the frequency distribution of PAS at 12 clock points was counted by clockwise. The PAS distribution at the middle point of PAS with continuous distribution and ≤6 clock points was assessed. Results: In all cases, PAS of the right eye was concentrated at 11:00 to 4:00 regions [range, 62.0% (129/208) to 78.8% (164/208)]. PAS of the left eye was concentrated at 7:00 to 1:00 regions [range, 50.0% (99/198) to 75.8% (150/198)]. When the PAS range of the atrial angle was ≤6 clock regions, it was mainly at 12:00 to 3:00 [range, 58.3% (74/127) to 67.7% (86/127)] in the right eye and at 10:00 to 12:00 [range, 54.8% (68/124) to 66.1% (82/124)] in the left eye. Among 121 cases (242 eyes) with both eyes involved, the PAS region was at 11:00 to 5:00 [range, 52.1% (63/121) to 79.3% (96/121)] in the right eye and at 8:00 to 1:00 [range, 50.4% (61/121) to 76.9% (93/121)] in the left eye. When the PAS range of the atrial angle was ≤6 clock regions, it was mainly at 12:00 to 4:00 [range, 53.2% (41/77) to 71.4% (55/77)] in the right eye and at 10:00 to 12:00 [range, 50.6% (39/77) to 64.9% (50/77)] in the left eye. In all cases, there were 171 cases of right eyes and 175 cases of left eyes with continuous angle PAS. The central PAS clock position of the right eye was mainly at 11:00 to 3:00 [range, 15.2% (26/171) to 24.0% (41/171)], and that of the left eye was mainly at 8:00 to 12:00 [range, 15.4% (27/175) to 20.6% (36/175)]. Among cases with both eyes involved, there were 98 cases of right eyes and 104 cases of left eyes with continuous angle PAS. The clock distribution of the middle position of the right eye angle PAS was concentrated at 11:00 to 3:00 [range, 17.3% (17/98) to 26.5% (26/98)], and that of the left eye was concentrated at 8:00 to 12:00 [range, 13.5% (14/104) to 20.2% (21/104)]. Conclusions: The PAS of PACG patients is mainly located in the upper and nasal sides, and the closer to the temporal side, the smaller the PAS frequency, showing a gradual downward trend. The PAS distribution of binocular angles is of obvious mirror symmetry. (Chin J Ophthalmol, 2021, 57: 666-671).

Mechanistic basis for receptor-mediated pathological α-synuclein fibril cell-to-cell transmission in Parkinson's disease

The spread of pathological α-synuclein (α-syn) is a crucial event in the progression of Parkinson's disease (PD). Cell surface receptors such as lymphocyte activation gene 3 (LAG3) and amyloid precursor-like protein 1 (APLP1) can preferentially bind α-syn in the amyloid over monomeric state to initiate cell-to-cell transmission. However, the molecular mechanism underlying this selective binding is unknown. Here, we perform an array of biophysical experiments and reveal that LAG3 D1 and APLP1 E1 domains commonly use an alkaline surface to bind the acidic C terminus, especially residues 118 to 140, of α-syn. The formation of amyloid fibrils not only can disrupt the intramolecular interactions between the C terminus and the amyloid-forming core of α-syn but can also condense the C terminus on fibril surface, which remarkably increase the binding affinity of α-syn to the receptors. Based on this mechanism, we find that phosphorylation at serine 129 (pS129), a hallmark modification of pathological α-syn, can further enhance the interaction between α-syn fibrils and the receptors. This finding is further confirmed by the higher efficiency of pS129 fibrils in cellular internalization, seeding, and inducing PD-like α-syn pathology in transgenic mice. Our work illuminates the mechanistic understanding on the spread of pathological α-syn and provides structural information for therapeutic targeting on the interaction of α-syn fibrils and receptors as a potential treatment for PD.

POS0664 A MULTICENTER RANDOMIZED STUDY IN RHEUMATOID ARTHRITIS TO COMPARE IGURATIMOD, METHOTREXATE, OR COMBINATION: 52 WEEK EFFICACY AND SAFETY RESULTS OF THE SMILE TRIAL

Background:

Iguratimod (IGU) has demonstrated efficacy and safety for active rheumatoid arthritis (RA) patients in double-blind clinical trials in China and Japan as a new disease-modifying anti-rheumatic drug (DMARD). There are no studies evaluating the radiographic progression of structural joint damage of IGU for the treatment of RA using the mTSS as the primary endpoint.

Objectives:

Our study was to evaluate the efficacy and safety of IGU monotherapy and IGU combined methotrexate (MTX) compared with MTX monotherapy, including the inhibitory effects of joint destruction.

Methods:

This randomized, double-blind, parallel-controlled, multicenter study in patients with active RA who have not previously used MTX and biological DMARDs (bDMARDs) (ClinicalTrials.gov Identifier NCT01548001) was carried out in China. Patients were randomized 1:1:1 to receive IGU 25 mg twice a day (bid), MTX 10mg once a week(qw) for the first 4 weeks and 15 mg once a week(qw) for week 5 to 52, or IGU combined MTX (IGU+MTX) for 52 weeks. The primary endpoints were to assess and compare American College of Rheumatology 20% (ACR20) response and the change of modified total Sharp scoring (mTSS) score over 52 weeks (Intention-to-treat, ITT analysis). The non-inferiority test was used to analyze the difference of ACR20 response at 52 weeks between the IGU monotherapy and the MTX monotherapy arms, and the non-inferiority limit value was 10%. The difference test was used for the comparison between the IGU+MTX and MTX monotherapy arms. Two-way ANOVA was used to analyze the difference of the changes of mTSS score of each arm compared with baseline value (0 week).

Results:

A total of 895 patients were randomized to IGU 25mg bid (n =297), MTX 10-15mg qw(n=293), and IGU+MTX (n=305). Baseline characteristics were comparable between the arms (Table 1).

Table 1.

Demographic and Other Baseline Characteristics (SAS)

IGUMTXIGU+MTXNumber of Subjects297293305Age, mean (SD) years46.87(10.67)47.63(10.70)48.37(10.69)Female/male, %77.44/22.5679.18/20.8278.03/21.97Duration of RA, mean(SD) years11.67±7.1611.60±7.9811.67±7.27CRP, mean(SD) mg/L222.32±35.4720.67±26.6119.74±31.38Tender joint count, mean (SD)14.59±9.1614.83±9.3014.93±9.88Swollen joint count, mean (SD)9.81±6.639.73±7.209.51±6.22DAS28-CRP, mean (SD)5.084±0.9945.102±0.9795.103±0.956HAQ score, mean (SD)15.82±11.2515.24±10.9316.06±10.92

SAS: Safety Analysis Set; CRP: C-reactive protein;

DAS28: disease activity score; HAQ: Health Assessment Questionnaire

The study met its primary endpoints. More concretely, IGU monotherapy and IGU+MTX were found to be superior to MTX at week 52 with a higher ACR20 response of 77.44%(230/297, P=0.0019) and 77.05%(235/305, P=0.0028) versus 65.87%(193/293) (fig 1). As shown in fig 1, the structural remission (ΔmTSS≤0.5) was statistically significant for IGU monotherapy (57.4%, P=0.0308) but not for IGU+MTX arm (55%) versus MTX monotherapy (47.8%).

Overall incidence of the adverse events (AEs) leading to study discontinuation were reported in 13.8% (41/297) in IGU monotherapy arm, 11.26% (33/293) in MTX monotherapy arm and 11.51% (35/305) patients in IGU+MTX arm. The incidence of adverse drug reactions (ADR) leading to study discontinuation were 11.45% (34/297), 8.53% (25/293) and 9.21% (28/305), respectively. There was no one death and no significant difference in all the safety indicators among the three arms.

Conclusion:

Iguratimod alone or in combination with MTX demonstrated superior efficacy with acceptable safety compared to MTX for patients with active RA who have not previously used MTX bDMARDs.

Disclosure of Interests:

None declared

Light-Controlled Tyrosine Nitration of Proteins

Tyrosine nitration of proteins is one of the most important oxidative post-translational modifications in vivo. A major obstacle for its biochemical and physiological studies is the lack of efficient and chemoselective protein tyrosine nitration reagents. Herein, we report a generalizable strategy for light-controlled protein tyrosine nitration by employing biocompatible dinitroimidazole reagents. Upon 390 nm irradiation, dinitroimidazoles efficiently convert tyrosine residues into 3-nitrotyrosine residues in peptides and proteins with fast kinetics and high chemoselectivity under neutral aqueous buffer conditions. The incorporation of 3-nitrotyrosine residues enhances the thermostability of lasso peptide natural products and endows murine tumor necrosis factor-α with strong immunogenicity to break self-tolerance. The light-controlled time resolution of this method allows the investigation of the impact of tyrosine nitration on the self-assembly behavior of α-synuclein.

Test of Lepton-Flavor Universality in B→K^{*}ℓ^{+}ℓ^{-} Decays at Belle

We present a measurement of R_{K^{*}}, the branching fraction ratio B(B→K^{*}μ^{+}μ^{-})/B(B→K^{*}e^{+}e^{-}), for both charged and neutral B mesons. The ratio for the charged case R_{K^{*+}} is the first measurement ever performed. In addition, we report absolute branching fractions for the individual modes in bins of the squared dilepton invariant mass q^{2}. The analysis is based on a data sample of 711  fb^{-1}, containing 772×10^{6}  BB[over ¯] events, recorded at the ϒ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. The obtained results are consistent with standard model expectations.

A novel partially open state of SHP2 points to a "multiple gear" regulation mechanism

The protein tyrosine phosphatase SHP2 mediates multiple signal transductions in various cellular pathways, controlled by a variety of upstream inputs. SHP2 dysregulation is causative of different types of cancers and developmental disorders, making it a promising drug target. However, how SHP2 is modulated by its different regulators remains largely unknown. Here, we use single-molecule fluorescence resonance energy transfer and molecular dynamics simulations to investigate this question. We identify a partially open, semiactive conformation of SHP2 that is intermediate between the known open and closed states. We further demonstrate a “multiple gear” regulatory mechanism, in which different activators (e.g., insulin receptor substrate-1 and CagA), oncogenic mutations (e.g., E76A), and allosteric inhibitors (e.g., SHP099) can shift the equilibrium of the three conformational states and regulate SHP2 activity to different levels. Our work reveals the essential role of the intermediate state in fine-tuning the activity of SHP2, which may provide new opportunities for drug development for relevant cancers.

Genetic diversity of Ethiopian sorghum reveals signatures of climatic adaptation

A large collection of Ethiopian sorghum landraces, characterized by agro-ecology and racial-group, was found to contain high levels of diversity and admixture, with significant SNP associations identified for environmental adaptation. Sorghum [Sorghum bicolor L. (Moench)] is a major staple food crop in Ethiopia, exhibiting extensive genetic diversity with adaptations to diverse agroecologies. The environmental and climatic drivers, as well as the genomic basis of adaptation, are poorly understood in Ethiopian sorghum and are critical elements for the development of climate-resilient crops. Exploration of the genome-environment association (GEA) is important for identifying adaptive loci and predicting phenotypic variation. The current study aimed to better understand the GEA of a large collection of Ethiopian sorghum landraces (n = 940), characterized with genome-wide SNP markers, to investigate key traits related to adaptation to temperature, precipitation and altitude. The Ethiopian sorghum landrace collection was found to consist of 12 subpopulations with high levels of admixture (47%), representing all the major racial groups of cultivated sorghum with the exception of kafir. Redundancy analysis indicated that agroecology explained up to 10% of the total SNP variation, and geographical location up to 6%. GEA identified 18 significant SNP markers for environmental variables. These SNPs were found to be significantly enriched (P < 0.05) for a priori QTL for drought and cold adaptation. The findings from this study improve our understanding of the genetic control of adaptive traits in Ethiopian sorghum. Further, the Ethiopian sorghum germplasm collection provides sources of adaptation to harsh environments (cold and/or drought) that could be deployed in breeding programs globally for abiotic stress adaptation.

Cardiac biomarkers of disordered eating as a function of diagnostic subtypes

OBJECTIVE

The purpose of this study was to identify cardiac biomarkers of disordered eating as a function of diagnostic subtype as assessed via self-report inventory.

METHOD

Mean heart rate (HR), systolic and diastolic blood pressure, mean R wave amplitude (mV), mean T wave amplitude (mV), QTc interval (sec), Tpeak-Tend interval prolongation (sec), QTc interval prolongation (sec), QRS prolongation (sec), and spectral indicators of cardiac dysfunction (LF/HF spectral ratio, HF spectral power) were assessed via electrocardiography among women with no eating disorder symptoms (n = 32), subclinical eating disorder symptoms (n = 92), anorexia nervosa (n = 7), bulimia nervosa (n = 89), binge eating disorder (BED: n = 20), and other specified feeding and eating disorders (OSFED: n = 19).

RESULTS

MANOVA results showed statistically significant group differences. Follow-up tests revealed significantly decreased mean R wave amplitude among participants with self-indicated clinical (bulimia nervosa, binge eating disorder) and subclinical forms of disordered eating compared to asymptomatic controls.

DISCUSSION

Results suggest decreased mean R wave amplitude is a promising cardiac biomarker of disordered eating.

[Expression of SOX-11 and TFE3 in solid-pseudopapillary tumor of pancreas and its clinical significance]

Objective: To investigate the expression status and diagnostic value of SRY related high mobility group box 11 (SOX-11) and transcription factor E-3 (TFE3) in solid pseudopapillary tumors of pancreas (SPTPs). Methods: Thirty-eight cases of SPTPs, 36 cases of well-differentiated pancreatic neuroendocrine tumors (PanNETs) and six cases of pancreatic acinar cell carcinomas (PACCs) were collected at the Affiliated Drum Tower Hospital of Nanjing University Medical School from 2012 to 2019. The expression of SOX-11, TFE3 and β-catenin was detected by immunohistochemistry, and the TFE3 gene status was detected by FISH in 18 cases of SPTPs. Results: Among the 38 SPTP patients, 29 were female and 9 were male, with a mean age of 50 years; among 36 PanNET patients, 32 were female and 4 were male, with a mean age of 39 years; for the six PACC patients, four were male and two were female, with a mean age of 60 years. β-catenin was positive in all 38 SPTPs, but was negative in all 36 PanNETs and 5/6 PACCs. SOX-11 was positive in 35/38 (92.1%) of SPTPs, but was negative in all 36 PanNETs and 6 PACCs. TFE3 was positive in 36/38 (94.7%) of SPTPs, but was negative in all 36 PanNETs and 6 PACCs. Among these three tumors, the specificity and sensitivity of β-catenin were 97.6% and 100.0%, the specificity and sensitivity of SOX-11 were 92.1% and 100.0%, the specificity and sensitivity of TFE3 were 94.7% and 100.0%, respectively. There was a significant difference of the expression status of all three markers in SPTPs compared with PanNETs and PACCs (P<0.01). The results of SOX-11 and TFE3 immunostaining showed high consistency (Kappa>0.6). No gene rearrangement (0/18) of TFE3 was found in SPTPs. Conclusion: SOX-11 and TFE3 are highly expressed in SPTPs, and their specificity in the differential diagnosis of SPTPs is better than that of β-catenin.