The effects of open and closed suctioning systems on neonatal pain and vital signs in neonatal intensive care units.

BACKGROUND: Endotracheal suctioning is a procedure used by neonatal intensive care unit nurses to maximize oxygenation and clear airways of secretions, and is one of the most common painful procedures causing stress in intubated newborns. AIM: This aim of this study is to compare the effects of open and closed endotracheal suctioning on pain, peak heart rate and oxygen saturation in neonates on mechanicalventilation. MATERIALS AND METHODS: This experimental-design study was conducted on 30 newborns who were mechanically ventilated in the tertiary neonatal intensive care unit of a public hospital. First, closed suctioning and then open suctioning was performed on patients during the day. Pain, peak heart rate and oxygen saturation levels were evaluated before, during and 30 min after each suctioning procedure. RESULTS: Of the newborns included in the study, 53.3 % were male and 36.6 % were admitted to intensive care unit due to a heart defect. No statistically significant differences were found in pain, peak heart rate, or oxygen saturation between the open and closed suctioning methods. However, oxygen saturation levels during suctioning were lower compared to levels before and 30 min after the procedure. Additionally, peak heart rate was lower during suctioning compared to 30 min afterward. CONCLUSIONS: The study concludes that there is no significant difference between open and closed suctioning techniques concerning pain, peak heart rate, and oxygen saturation. IMPLICATIONS TO PRACTICE: Given its sterility and ease of use, the closed suction method may be preferable in clinical settings.

[Influence of the Use of a Closed System Drug Transfer Device on the Preparation Time of Anticancer Drugs].

A closed system drug transfer device (CSTD) helps to minimize unnecessary exposure of healthcare workers such as pharmacists to hazardous drugs. One of the concerns in using CSTDs to prepare anticancer drugs is their influence on preparation time. Therefore, we compared the time needed to prepare anticancer drugs with the CSTDs NEOSHIELD® and BD PhaSeal® system and with an injection needle. In the comparison of NEOSHIELD® and an injection needle, the preparation time of the liquid formulations of the cytotoxic drugs irinotecan, eribulin, cisplatin, docetaxel, and paclitaxel was significantly shorter with the injection needle and that of gemcitabine was significantly shorter with NEOSHIELD®, but that of oxaliplatin, carboplatin, and doxorubicin was not significantly different between the two methods; the preparation time of the liquid formulations of the molecular-targeted drugs atezolizumab, obinutuzumab, cetuximab, daratumumab and vorhyaluronidase alfa, nivolumab, ramucirumab, and rituximab was significantly shorter with NEOSHIELD® and that of bevacizumab and pembrolizumab was significantly shorter with the injection needle; and the preparation time of the lyophilized formulation of cytotoxic and molecular-targeted drugs was not significantly different between the two methods. In the comparison of NEOSHIELD® and BD PhaSeal® system, the preparation time of cyclophosphamide and ifosfamide was significantly shorter with NEOSHIELD®, but that of bendamustine was not significantly different between the two CSTDs. In conclusion, these results suggest that the preparation time with CSTDs may be similar to or shorter than that with an injection needle, depending on the type of CSTD and the drug formulation and type.

The Impact of Open versus Closed Computer-Aided Design/Computer-Aided Manufacturing Systems on the Marginal Gap of Zirconia-Reinforced Lithium Silicate Single Crowns Evaluated by Scanning Electron Microscopy: A Comparative In Vitro Study.

This study aimed to compare the impact of CAD/CAM closed systems and open systems on the marginal gap of monolithic zirconia-reinforced lithium silicate (ZLS) ceramic crowns, as both systems are used in everyday dentistry, both chair-side and laboratory. For the closed system, 20 plastic teeth were scanned by a Primescan intra-oral scanner (IOS), and for the open system, the same number of plastic teeth were scanned by Trios 4 IOS. For the closed system, CEREC software was used, and for the open system, EXOCAD software was used. All 40 ZLS crowns were grinded by the same four-axis machine and cemented with Temp-bond, followed by self-adhesive resin cement. For each type of cement, an evaluation of the marginal gap was conducted by scanning electron microscopy (SEM). Before comparisons between the groups, a Kolmogorov-Smirnov test was performed on the study variables showing a normal distribution (p > 0.05). Independent T tests (α = 0.05) and paired-sample T tests (α = 0.05) were used. The independent T test found no significant mean marginal gap differences in the zirconia-reinforced lithium silicate crowns bonded with Temp-bond and scanned by Primescan (28.09 µm ± 3.06) compared to Trios 4 (28.94 µm ± 3.30) (p = 0.401), and there was no significant mean marginal gap differences in zirconia-reinforced lithium silicate crowns bonded with self-adhesive resin cement (Gcem ONE) and scanned by Primescan (46.70 µm ± 3.80) compared to Trios 4 (47.79 µm ± 2.59) (p = 0.295). Paired-sample T tests showed significantly higher mean marginal gaps with Gcem ONE compared to Temp-bond for the total mean marginal gap when scanning with Primescan (p = 0.0005) or Trios 4 (p = 0.0005). In everyday dentistry, both closed systems (Primescan with Cerec) and open systems (Trios 4 with Exocad) can be used to achieve an acceptable (<120 µm) marginal gap for ZLS CELTRA® DUO single crowns. There is a significant difference between cementation with Temp-bond and Gcem ONE self-adhesive resin cement (p < 0.05).

Implementing a closed system drug transfer device to enable nurses to prepare monoclonal antibody treatment.

BACKGROUND: Efforts to increase capacity for oncology treatment in the author's Chemotherapy Day Unit, while allowing staff to treat more patients and offer more flexibility to patients, increased strain on the Aseptic Pharmacy at the author's Trust. Therefore, the possibility of nurse-led drug preparation was explored. AIMS: Nurse-led monoclonal antibody (MAb) preparation was piloted to investigate whether a reduction in reliance on Aseptic Pharmacy could co-exist with maintaining optimal treatment capacity. The effectiveness of a closed system transfer device (CSTD) to protect nurses against drug exposure was also explored. METHODS: A risk assessment for MAbs considered for nurse-led preparation was created, alongside a procedure for the safe handling of systemic anti-cancer therapy (SACT) with the use of a CSTD. FINDINGS: The pilot resulted in an 89% reduction in the time patients had to wait for MAbs to be prepared. Seven oncology drugs were included in the new procedure without increasing the risk of exposure for nurses. CONCLUSION: The pilot successfully reduced demand on Aseptic Pharmacy while enabling efficient capacity use on the Chemotherapy Day Unit. The use of the CSTD minimised the risk of nurse exposure to SACT.

Impact on Quality during In-Use Preparation of an Antibody Drug Conjugate with Eight Different Closed System Transfer Device Brands.

The aim of this study was to investigate the in-use compatibility of eight commercially available closed system transfer device brands (CSTDs) with a formulated model antibody drug conjugate (ADC). Overall, in-use simulated dosing preparation applying the CSTD systems investigated raised concerns for several product quality attributes. The incompatibilities observed were mainly associated with increased visible and subvisible particles formation as well as significant changes in holdup volumes. Visible and subvisible particles contained heterogeneous mixtures of particle classes, with the majority of subvisible particles associated with silicone oil leaching from CSTD systems during simulated dose preparation upon contact with the ADC formulation. These observations demonstrate that CSTD use may adversely impact product quality and delivered dose which could potentially lead to safety and efficacy concerns during administration. Other product quality attributes measured including turbidity, color, ADC recovery, and purity by size exclusion HPLC, did not show relevant changes. It is therefore strongly recommended to test and screen the compatibility of CSTDs with the respective ADC, in a representative in-use simulated administration setting, during early CMC development, i.e., well before the start of clinical studies, to include information about compatibility and to ensure that the CSTD listed in the manuals of preparation for clinical handling has been thoroughly assessed before human use.

New Generation Nebulizers.

Standard nebulizers are intended for general purpose use and typically are continuously operated jet or ultrasonic nebulizers. Evolutionary developments such as breath-enhanced and breath-triggered devices have improved delivery efficiency and ease of use, yet are still suitable for delivery of nebulized medications approved in this category. However, recent developments of vibrating membrane or mesh nebulizers have given rise to a significant increase in delivery efficiency requiring reformulation of former drug products or development of new formulations to match the enhanced delivery characteristics of these new devices. In addition, the electronic nature of the new devices enables tailoring to specific applications and patient groups, such as guiding or facilitating optimal breathing and improving adherence to the therapeutic regimen. Addressing these patient needs leads to new nebulization technologies being embedded in devices with fundamentally distinct functionality, modes of operation and patient interfaces. Therefore, new generation nebulizers can no longer be regarded as one category with fairly similar performance characteristics but must be clinically tested and approved as drug/device combinations together with the specific drug formulation, similar to the approval of pressurized metered-dose inhalers and dry powder inhalers. From a regulatory viewpoint, it is required that drug and device are associated with each other as combinations by clear, mutually conforming labels or, even more desirably, by distinct container-closure systems (closed system nebulizer).

Experimental Identification of Potential Martian Biosignatures in Open and Closed Systems.

NASA's Perseverance and ESA's Rosalind Franklin rovers have the scientific goal of searching for evidence of ancient life on Mars. Geochemical biosignatures that form because of microbe-mineral interactions could play a key role in achieving this, as they can be preserved for millions of years on Earth, and the same could be true for Mars. Previous laboratory experiments have explored the formation of biosignatures under closed systems, but these do not represent the open systems that are found in natural martian environments, such as channels and lakes. In this study, we have conducted environmental simulation experiments using a global regolith simulant (OUCM-1), a thermochemically modelled groundwater, and an anaerobic microbial community to explore the formation of geochemical biosignatures within plausible open and closed systems on Mars. This initial investigation showed differences in the diversity of the microbial community developed after 28 days. In an open-system simulation (flow-through experiment), the acetogenic Acetobacterium (49% relative abundance) and the sulfate reducer Desulfosporomusa (43% relative abundance) were the dominant genera. Whereas in the batch experiment, the sulfate reducers Desulfovibrio, Desulfomicrobium, and Desulfuromonas (95% relative abundance in total) were dominant. We also found evidence of enhanced mineral dissolution within the flow-through experiment, but there was little evidence of secondary deposits in the presence of biota. In contrast, SiO2 and Fe deposits formed within the batch experiment with biota but not under abiotic conditions. The results from these initial experiments indicate that different geochemical biosignatures can be generated between open and closed systems, and therefore, biosignature formation in open systems warrants further investigation.

Development of a robotic cluster for automated and scalable cell therapy manufacturing.

BACKGROUND AIMS: The production of commercial autologous cell therapies such as chimeric antigen receptor T cells requires complex manual manufacturing processes. Skilled labor costs and challenges in manufacturing scale-out have contributed to high prices for these products. METHODS: We present a robotic system that uses industry-standard cell therapy manufacturing equipment to automate the steps involved in cell therapy manufacturing. The robotic cluster consists of a robotic arm and customized modules, allowing the robot to manipulate a variety of standard cell therapy instruments and materials such as incubators, bioreactors, and reagent bags. This system enables existing manual manufacturing processes to be rapidly adapted to robotic manufacturing, without having to adopt a completely new technology platform. Proof-of-concept for the robotic cluster's expansion module was demonstrated by expanding human CD8+ T cells. RESULTS: The robotic cultures showed comparable cell yields, viability, and identity to those manually performed. In addition, the robotic system was able to maintain culture sterility. CONCLUSIONS: Such modular robotic solutions may support scale-up and scale-out of cell therapies that are developed using classical manual methods in academic laboratories and biotechnology companies. This approach offers a pathway for overcoming manufacturing challenges associated with manual processes, ultimately contributing to the broader accessibility and affordability for personalized immunotherapies.

Clinical grade multiparametric cell sorting and gene-marking of regulatory T cells.

BACKGROUND AIMS: Regulatory T cells (Tregs) are the main mediators of peripheral tolerance. Treg-directed therapy has shown promising results in preclinical studies of diverse immunopathologies. At present, the clinical applicability of adoptive Treg transfer is limited by difficulties in generating Tregs at sufficient cell dose and purity. METHODS: We developed a Good Manufacturing Practice (GMP) compliant method based on closed-system multiparametric Fluorescence-Activated Cell Sorting (FACS) to purify Tregs, which are then expanded in vitro and gene-marked with a clinical grade retroviral vector to enable in vivo fate tracking. Following small-scale optimization, we conducted four clinical-scale processing runs. RESULTS: We showed that Tregs could be enriched to 87- 92% purity following FACS-sorting, and expanded and transduced to yield clinically relevant cell dose of 136-732×106 gene-marked cells, sufficient for a cell dose of at least 2 × 106 cells/kg. The expanded Tregs were highly demethylated in the FOXP3 Treg-specific demethylated region (TSDR), consistent with bona fide natural Tregs. They were suppressive in vitro, but a small percentage could secrete proinflammatory cytokines, including interferon-γ and interleukin-17A. CONCLUSIONS: This study demonstrated the feasibility of isolating, expanding and gene-marking Tregs in clinical scale, thus paving the way for future phase I trials that will advance knowledge about the in vivo fate of transferred Tregs and its relationship with concomitant Treg-directed pharmacotherapy and clinical response.

An assessment of exposed syringe inner walls as a route of exposure from hazardous drugs.

INTRODUCTION: Maintaining safe working environments for health care personnel, especially for those who regularly handle hazardous drugs (HDs), is of utmost importance. Studies have shown that when closed system transfer devices (CSTDs) are used with standard open barrel syringes, cyclophosphamide (CP), a commonly used HD, is transferred to the syringe plunger during compounding or administration processes. This contamination can then be transferred to the work environment, endangering workers. PURPOSE: The purpose of this study was to quantify HD contamination of the inner surface of standard open barrel syringes and to compare contamination levels between three commonly used HDs: 5-fluorouracil (5-FU), CP, and ifosfamide (IF). METHODS: Each HD was transferred from a vial to an intravenous (IV) bag using a standard open barrel syringe and Becton, Dickinson and Company (BD) PhaSealTM CSTD connectors. Samples were taken from the inner surface of each of the syringe barrels to measure the amount of HD contamination. Each drug was tested 15 times and compared to a positive control. RESULTS: Significant amounts of each drug were transferred to the inner surfaces of the syringes. The average amounts of each drug measured were: 5-FU, 1327.7 ng (standard deviation [SD] = 873.6 ng); CP, 1074.8 ng (SD = 481.6 ng); and IF, 1700.0 ng (SD = 1098.1 ng). There was no statistically significant difference between the three drugs (p = 0.14). CONCLUSION: This study underscores the presence of HD contamination on standard open barrel syringe inner surfaces after transfer of drug from vial to syringe to IV bag. Such contamination could be spread in the working environment and expose health care workers to harm.

Evaluating drug stability and sterility in single-dose vials when accessed with a closed system transfer device.

Background: Impact of drug wastage is a legitimate and persistent concern. Financial impact of drug waste is borne by the hospital network, patients, and healthcare systems. Measures to reduce drug wastage may have a positive impact throughout healthcare systems. Objective: This study investigated the stability and sterility of single-dose vials when repeatedly accessed with a closed system transfer device. By evaluating the sterility and stability, these results may be used to validate the extension of vial usage and lead to potential drug wastage reduction. Methods: Sterility testing was performed in accordance with US Pharmacopeia 71. A closed system transfer device was incorporated into simulated compounding tasks, utilizing growth media. Simulated compounding tasks were performed in the clinical environment, followed by incubation to stimulate growth. Stability testing was performed in accordance with US Pharmacopeia monographs at multiple timepoints post access. Test samples were comparatively tested via high-performance liquid chromatography to freshly opened vials at each timepoint. Results: No growth was observed in test samples. Control vials displayed growth, where appropriate. The drugs retained stability, when compared to freshly opened vials at 0, 24, 48, and 72 h, post access. Conclusions: This study confirms that closed system transfer devices do not contribute to microbial contamination of drug vials, following the repeated access, for up to 7 days and the tested drugs retained equivalent chemical stability for up to 72 h post access. This study may offer a manner by which a facility may assess single-dose vials' sterility and stability, following repeated access by a closed system transfer device.

Characterization of Silicone from Closed System Transfer Devices and its Migration into Pharmaceutical Drug Products.

Closed System Transfer Devices (CSTDs) are increasingly used in healthcare settings to facilitate compounding of hazardous drugs but increasingly also therapeutic proteins. However, their use may significantly impact the quality of the sterile product. For example, contamination of the product solution may occur by leaching of silicone or particulates from the CSTDs. It was therefore the aim of the present study to identify and quantify the types of silicone oil in a panel of typically used CSTDs. Particles found after simulated CSTD compounding processes were evaluated using Light Obscuration and Micro-Flow Imaging and were confirmed to be silicone oil particles. The number of particulates shed from CTSDs was in single cases exceeding pharmacopeial limits for a final parenteral product. Using X-ray microtomography, lubrication was shown to be primarily applied at connecting parts of the CSTD. Quantitative and qualitative analysis by Fourier transform infrared spectroscopy (FTIR) revealed a total released amount between 0.8 and 16 mg per CSTD of polydimethylsiloxane or polymethyltrifluoropropylsiloxane per CSTD. While pronounced differences in total silicone content between CSTDs were observed, it did not fully correlate with particle contamination in the test solutions, potentially due to variations in CSTD design. The impact of typical surfactants in biological formulations on silicone migration into product was additionally evaluated. We conclude that CSTDs may compromise final product quality, as (different types of) silicone oil may be released from these devices and contaminate the administered product.

Impact of Closed System Transfer Device (CSTD) Handling Procedure for Low-Transfer-Volume Dose Preparation of Biologic Drug Products.

Many challenges have been identified for ensuring compatibility of closed system transfer devices (CSTDs) with biologic drug products. One challenge is large hold-up volumes (HUVs) of CSTD components, which can be especially problematic with early-stage biologics when low transfer volumes smaller than the nominal fill volume may be used to achieve a wide range of doses with a single drug product configuration. Here, we identified possible CSTD handling techniques during dose preparation of a drug product requiring small volume transfers during reconstitution, intermediate dilution, and dilution in an IV bag, and systematically evaluated the impact of these handling procedures on the ability to deliver an accurate dose to the next step. We show that small changes to CSTD procedures can have a major impact on dose accuracy, depending on both CSTD HUVs and drug product-specific transfer volumes. We demonstrate that it is possible to craft CSTD instructions for use to mitigate these issues, and that the dose accuracy for specific drug product/CSTD combinations can be estimated using theoretical equations. Finally, we explored potential downsides of these mitigations. Our results emphasize key factors for consideration by both drug and CSTD manufacturers when assessing compatibility and providing CSTD instructions for use with biologics requiring low transfer volumes during dose preparation.

Retrospective and FMECA analysis of failures in closed-system devices.

INTRODUCTION: Cytotoxic drugs can be hazardous to healthcare workers involved in their preparation and/or administration. Exposure occurs during routine handling of drug vials and ampoules, preparation, administration and disposal of cytotoxic waste. The use of closed-system devices provides protection against exposure to cytotoxics, but these devices are the subject of numerous incidents. Given the nature of the drugs they contain, these incidents can be dangerous for the personnel handling them. OBJECTIVE: The aim of our study is to analyze material vigilance data relating to problems frequently encountered with the various consumables of the closed system and to assess the risk of exposure of personnel to cytotoxic drugs when using these using the Failure Mode and Criticality Analysis (FMECA) method. MATERIALS AND METHODS: Our study was conducted at the pharmacy of the National Institute of Oncology, the closed system drug transfer device (CSDT) used is a ChemoClave-ICU®, This device is mechanical and needleless For the materiovigilance study we carried out a retrospective study over the period from 2019 to 2022, analyzing materiovigilance data collected by National Institute of Oncology's materiovigilance and pharmacovigilance cell. Our team, trained in the FMECA method, conducted the study over a three-month period, between September and November 2022. The method was used to assess the risks incurred by staff when using the CSDT device to prepare cytotoxic drugs. CONCLUSION: Our study revealed that the most frequent incident was linked to a manufacturing defect in the device in question. According to the FMECA analysis, this incident represents a major risk, as its occurrence hampers the cytotoxic preparation process. CSDT have the advantage of being easy to use and acceptable to staff, but standards need to be developed and validated to assess the performance of these devices.

Effects of temperature on metabolic rate during metamorphosis in the alfalfa leafcutting bee.

Spring conditions, especially in temperate regions, may fluctuate abruptly and drastically. Environmental variability can expose organisms to temperatures outside of their optimal thermal ranges. For ectotherms, sudden changes in temperature may cause short- and long-term physiological effects, including changes in respiration, morphology, and reproduction. Exposure to variable temperatures during active development, which is likely to occur for insects developing in spring, can cause detrimental effects. Using the alfalfa leafcutting bee, Megachile rotundata, we aimed to determine if oxygen consumption could be measured using a new system and to test the hypothesis that female and male M. rotundata have a thermal performance curve with a wide optimal range. Oxygen consumption of M. rotundata pupae was measured across a large range of temperatures (6-48°C) using an optical oxygen sensor in a closed respirometry system. Absolute and mass-specific metabolic rates were calculated and compared between bees that were extracted from their brood cells and those remaining in the brood cell to determine whether pupae could be accurately measured inside their brood cells. The metabolic response to temperature was non-linear, which is an assumption of a thermal performance curve; however, the predicted negative slope at higher temperatures was not observed. Despite sexual dimorphism in body mass, sex differences only occurred in mass-specific metabolic rates. Higher metabolic rates in males may be attributed to faster development times, which could explain why there were no differences in absolute metabolic rate measurements. Understanding the physiological and ecological effects of thermal environmental variability on M. rotundata will help to better predict their response to climate change.

Developing a flowchart to evaluate the use of Closed System Drug-Transfer Devices with monoclonal antibodies: Focus on the clinical trial setting.

OBJECTIVE: Available guidelines are ambiguous about safe handling monoclonal antibodies (MABs) and whether or not to use a Closed System Drug-Transfer Device (CSTD). In this article we want to describe a standardized working method on handling MABs in a clinical trial setting. DATA SOURCES: The current workflow at the clinical trial unit of the Ghent University Hospital was critically analyzed, after which an extensive literature review was performed using the National Institute for Occupational Safety and Health Working Group guidelines and the database PubMed (Keywords: monoclonal antibodies, closed system transfer devices, safety guidelines, safe handling, management, administration, (bio)compatibility, volume loss, contamination, clinical trial unit. Period: 2020-2022). DATA SUMMARY: Literature data are ambiguous. CSTDs can reduce cross-contamination and minimize exposure to potential hazardous drugs for healthcare professionals. However, in recent years more questions have been raised about their in-use compatibility and their impact on final product quality. This makes the debate on implementing CSTDs a hot topic in daily pharmacy practice and demands a holistic and standardized approach when deciding whether or not to use a CSTD when handling MABs. In a clinical trial setting, where safety data are frequently not available and the compatibility of CSTDs and investigational product is often unknown, this poses additional challenges that need to be taken into account. CONCLUSION: We developed a flowchart which standardizes the use of a CSTD when handling MABs. It allows other healthcare professionals and clinical trial sponsors to define and evaluate the necessary criteria when standardizing the position of a CSTD in their safe handling procedures.

Evaluating Ecological Impact and Sustainability in the Manufacturing of Advanced Therapies: Comparative Analysis of Greenhouse Gas Emissions in the Production of ATMPs in Open and Closed Systems.

The primary aim of this systematic analysis is to highlight opportunities to improve the environmental impact of advanced therapy medicinal products (ATMP) manufacturing. We have compared the Greenhouse Gas (GHG) emissions expressed in CO2eq of a classic clean room open system (AinB) Cell Factory versus a comparable closed system equipped with isolators (AinD). We have therefore outlined a theoretical situation to simulate the use of a closed system with an equivalent production output to that obtained in the Cell Factory (CF) of the Regina Margherita Children's Hospital. Open and closed systems for ATMPs have been compared as regards energy requirements, ecological footprints, and costs by analyzing a hypothetic cell production cycle of 21 days. The results demonstrate energy saving and a reduction of 52% in GHG emissions using closed systems per process cycle. Moreover, a reduction in production costs in an isolator setting is also evident. This study shows that the closed system solution has evident advantages compared with the open one.

Insights into the life-cycle of aerobic granular sludge in a continuous flow membrane bioreactor by tracing its heterogeneous properties at different stages.

This work gave insights into the life-cycle of aerobic granular sludge (AGS) by tracing its heterogeneity in the basic properties at different stages in a closed system (a continuous flow membrane bioreactor, MBR), including physical and chemical characteristics and microbial communities. The results indicate that the entire life-cycle consists of the following four stages, namely, the initial, growing, mature and cleaved stages, where multiple AGS properties synergistically affect the rheological properties of the AGS over its life-cycle. The storage modulus (G') of AGS reached its maximum value at the mature stage, whose value was significantly and positively correlated with the protein (PN) in extracellular polymeric substances (EPS) and granule size, specifically the peak area of granule size distribution, but this value was strongly and negatively correlated with the roughness. The AGS at the mature stage would be more vulnerable to be destroyed than that at other stages under the condition of higher shear strain, such as γ = 50%, which was associated with larger granule size and fewer polysaccharide (PS)-related functional groups (especially in the soluble microbial products (SMPs) in the outermost layer of AGS), and the decrease in PS was correlated with a higher relative abundance of Chloroflexi. Additionally, the value of shear strain that AGS was subjected to had a good linear correlation (R2=0.993) with the Young's modulus, which indicated the ability of AGS to resist deformation improved with increasing values of shear strain.