Application of plasma donor-derived cell free DNA for lung allograft rejection diagnosis in lung transplant recipients.

BACKGROUND: Donor-derived cell-free DNA (dd-cfDNA) has been applied to monitor acute rejection (AR) in kidney and heart transplantation. This study was aimed to investigate the application of dd-cfDNA levels in the diagnosis of AR and chronic lung allograft dysfunction (CLAD) among the lung transplantation recipients (LTRs). METHODS: One hundred and seventy LTRs were enrolled at the First Affiliated Hospital of Guangzhou Medical University between 1 June 2015 and 30 March 2021. Patients were divided into 4 groups: stable group, AR group, infection group and CLAD group. The level of dd-cfDNA was analyzed using target region sequencing and the performance characteristics of dd-cfDNA for diagnosis of AR and CLAD were determined, respectively. RESULTS: Kruskal-Wallis test showed that there were some significant differences in the level of dd-cfDNA (%) among the 4 groups, with p < 0.001. Among them, the level of dd-cfDNA (%) was highest (median 2.17, IQR [1.40-3.82]) in AR group, and higher in CLAD group (median 1.07, IQR [0.98-1.31]), but lower in infection group (median 0.71, IQR [0.57-1.07]) and lowest in stable group (median 0.71, IQR [0.61-0.84]). AUC-ROC curve analysis showed that the threshold of dd-cfDNA for AR was 1.17%, with sensitivity being 89.19% and specificity being 86.47%, and the optimal threshold of 0.89% was determined of CLAD, with sensitivity being 95.00% and specificity of 76.99%. CONCLUSIONS: Plasma dd-cfDNA could be a useful tool for the assessment of lung allograft rejection, including AR and CLAD, and holds promise as a noninvasive biomarker for "allograft injury" in both acute and chronic rejection following lung transplantation.

Outcomes after lung transplantation among Chinese patients with connective tissue disease-associated interstitial lung disease and pulmonary hypertension: a retrospective cohort study.

OBJECTIVES: The present study aimed to compare the post-lung transplant survival and complications of connective tissue disease (CTD)-related interstitial lung disease (ILD) and/or pulmonary arterial hypertension with idiopathic pulmonary fibrosis (IPF). METHODS: The clinical data of patients with CTD-ILD or IPF who received lung transplantation between 2015 and 2020 were retrospectively reviewed. Cumulative survival rates after transplantation were estimated using the Kaplan-Meier method. RESULTS: The study included 31 patients with confirmed CTD-ILD and 98 with IPF. Patients with CTD-ILD were significantly younger (53.2 ± 13.7 vs. 62.3 ± 7.2 years, p=0.001) and more likely female (61.3% vs. 7.1%, p<0.001) than patients with IPF. No significant difference was noticed in the 1-year and 5-year survival rates between CTD-ILD and IPF patients (1-year, 73.2% vs 71.4%, p=0.76; 5-year, 69.1% vs. 39.5%, p=0.21). The incidence of primary graft dysfunction was significantly higher in CTD-ILD patients (90.3% vs. 70.4%, p=0.03), while there was no significant difference in primary graft dysfunction-related mortality (6.5% vs. 6.1%, p=0.95) between the two groups. CONCLUSIONS: There was no significant difference in post-lung transplant survival and complications between CTD-ILD and IPF.

Cytomegalovirus seroprevalence, infection, and disease in Chinese thoracic organ transplant recipients: a retrospective cohort study.

BACKGROUND: Cytomegalovirus (CMV) infection is a leading cause of morbidity and mortality after transplantation. This study aimed to investigate CMV seroprevalence, infection, and disease in Chinese thoracic organ transplant recipients. METHODS: The clinical data of the patients who underwent lung and/or heart transplantation between January 2015 and October 2020 were retrospectively collected from four transplantation centers in China. RESULTS: A total of 308 patients were analyzed. The CMV serostatus was donor positive (D+) recipient negative (R-) in 19 (6.17%) patients, D+/R+ in 233 (75.65%), D-/R+ in 36 (11.69%), and D-/R- in 20 (6.50%). CMV DNAemia was detected in 52.3% of the patients and tissue-invasive CMV disease was diagnosed in 16.2% of the patients. Only 31.8% of the patients adhered to the postdischarge valganciclovir therapy. The D+/R- serostatus (odds ratio [OR]: 18.32; 95% confidence interval [CI]:1.80-188.68), no valganciclovir prophylaxis (OR: 2.64; 95% CI: 1.05-6.64), and higher doses of rabbit anti-human thymocyte globulin (> 2 mg/kg) (OR: 4.25; 95% CI: 1.92-9.42) were risk factors of CMV disease. CONCLUSION: CMV seroprevalence was high in Chinese thoracic organ transplant donors and recipients. The low adherence rate to the postdischarge CMV prophylaxis therapy in Chinese patients is still an unresolved issue.

Metagenomic Next-Generation Sequencing for Diagnosing Infections in Lung Transplant Recipients: A Retrospective Study.

Background: Accurate identification of pathogens is essential for the diagnosis and control of infections. We aimed to compare the diagnostic performance of metagenomic next-generation sequencing (mNGS) and conventional detection methods (CDM) in lung transplant recipients (LTRs). Methods: We retrospectively analyzed 107 LTRs with suspected infection of pulmonary, blood, central nervous system or chest wall between March 2018 and November 2020. Bronchoalveolar lavage fluid and other body fluids were subject to pathogen detection by both mNGS and CDM. Results: Of the 163 specimens, 84 (51.5%) tested positive for both mNGS and culture, 19 (11.7%) of which were completely consistent, 44 (27.0%) were partially congruent, and 21 (12.9%) were discordant (kappa = .215; p = .001). Compared with CDM, mNGS detected a higher diversity of pathogens. Moreover, the turn-around time was significantly shorter for mNGS compared with culture (2.7 ± .4 vs. 5.5 ± 1.6 days, p < .001). As an auxiliary method, treatment strategies were adjusted according to mNGS findings in 31 cases (29.0%), including eight patients with non-infectious diseases, who were finally cured. Conclusion: mNGS can identify pathogens with a shorter turn-around time and therefore provide a more accurate and timely diagnostic information to ascertaining pulmonary infections. mNGS might have a role in differentiating infectious from non-infectious lung diseases in LTRs.

High-throughput next-generation sequencing for identifying pathogens during early-stage post-lung transplantation.

BACKGROUND: High-throughput next-generation sequencing (HT-NGS) has the potential to detect a large variety of pathogens; however, the application of HT-NGS in lung transplant (LTx) recipients remains limited. We aimed to evaluate the value of HT-NGS for pathogen detection and diagnosis of pulmonary infection during early-stage post-lung transplantation. METHODS: In this retrospective study, we enrolled 51 LTx recipients who underwent lung transplantation between January 2020 and December 2020. Bronchoalveolar lavage fluid (BALF) samples were collected for the detection of pathogens using both HT-NGS and conventional microbiological testing. The detection of pathogens and diagnostic performance of HT-NGS were compared with that of conventional methods. RESULTS: HT-NGS provided a higher positive rate of pathogen detection than conventional microbiological testing (88.24% vs. 76.47%). The most common bacteria detected via HT-NGS during early-stage post-lung transplantation were Enterococcus, Staphylococcus, Pseudomonas and Klebsiella, while all fungi were Candida and all viruses were Herpesvirus. Uncommon pathogens, including Strongyloides, Legionella, and Mycobacterium abscesses were identified by HT-NGS. The sensitivity of HT-NGS for diagnosing pulmonary infection was significantly higher than that of conventional microbiological testing (97.14% vs. 68.57%; P < 0.001). For three LTx recipients, treatment regimens were adjusted according to the results of HT-NGS, leading to a complete recovery. CONCLUSION: HT-NGS is a highly sensitive technique for pathogen detection, which may provide diagnostic advantages, especially in LTx recipients, contributing to the optimization of treatment regimens against pulmonary infection during early-stage post-lung transplantation.

Cough in hypereosinophilic syndrome: case report and literature review.

BACKGROUND: Cough and airway eosinophilic inflammation has not been highlighted in hypereosinophilic syndrome (HES). CASE PRESENTATION: We report 2 further cases and reviewed the clinical features and treatment of HES present with cough from the literature. Both cases were middle age male, presenting with chronic cough, airway eosinophilic inflammation and hyper eosinophilia who have been previous misdiagnosed as cough-variant asthma and failed anti-asthma treatment. PDGFRA fusion gene was confirmed in one case, but not in the other case. Both had evidence of myeloproliferative features. The tyrosine kinase inhibitor, imatinib, resulted in complete resolution of eosinophilia and cough. By searching PubMed, we found 8 HES cohorts of 411 cases between 1975 and 2013, where the incidence of cough was 23.11%. Sixteen case reports of HES presented with cough as predominant or sole symptom, with nine male patients with positive PDGFRA fusion gene, who responded well to imatinib. Six of seven patients, who tested negative for the PDGFRA, responded to systemic glucocorticoids. CONCLUSIONS: Cough and airway eosinophilic inflammation is common in some HES patients. PDGFRA+ HES patients present with chronic cough respond well to imatinib. Our case reports indicate that PDGFRA negative HES patients may respond to imatinib as well.

Plasma myostatin levels are related to the extent of right ventricular dysfunction in exacerbation of chronic obstructive pulmonary disease.

OBJECTIVE: To investigate the relationship between plasma myostatin levels and right ventricle (RV) dysfunction (RVD) in acute exacerbation of chronic obstructive pulmonary disease (AECOPD). METHODS: The study recruited 84 patients with AECOPD. Plasma myostatin was analyzed and tricuspid annular plane systolic excursion (TAPSE) < 16 mm was used as the main indicator for RVD. RESULTS: Plasma myostatin levels were significantly higher in 47 patients with RVD than 37 ones without (P < 0.005). Multivariate regression analysis revealed that myostatin levels correlated significantly with TAPSE values and RV myocardial performance index (p < 0.001) among the study patients. CONCLUSION: Plasma myostatin is a potential biomarker for improving diagnosis of RVD in AECOPD.

Physiological Significance of Well-tolerated Inspiratory Pressure to Chronic Obstructive Pulmonary Disease Patient with Hypercapnia During Noninvasive Pressure Support Ventilation.

The inspiratory pressure is often set by tolerance of chronic obstructive pulmonary disease (COPD) patient during noninvasive pressure support ventilation (PSV). However, physiological effects of this setting remain unclear. This study was undertaken to assess the physiological effect of highest tolerated assist level on COPD patient. The baseline inspiratory pressure (PS) was titrated by tolerance in 15 severe COPD patients with hypercapnia during acute exacerbation. In addition to the baseline PS, an additional decrease by 25% (PS- = 75% PS) or increase by 25% (PS+ = 125% PS) of PS was applied to the patients. Each level lasted at least 20 minutes. Respiratory rate (RR), tidal volume (Vt), inspiratory effort (PTPpesin/min), and neuro-ventilatory coupling (VE/RMS%) were measured. Asynchrony Index (AI) was calculated. The Vt and VE/RMS% were significantly increased by PS level (Vt: 561 ± 102 ml, VE/RMS%: 1.06 ± 0.42 L/%, comfort score: 7.5 ± 1.1). The inspiratory muscles were sufficiently unloaded (PTPpesin/min 56.67 ± 32.71 cmH2O.S/min). In comparison with PS, PS+ resulted in a further increase in Vt, VE/RMS% and AI (P < 0.01), with no further reduction in neural drive (RMS) and respiratory muscle activity (P > 0.05). Increasing inspiratory pressure significantly enhances the VE/RMS% and Vt. However, the inspiratory pressure higher than COPD patient's most tolerated level cannot lead to further reduction in respiratory muscle load and RMS, but more asynchrony events. Physiological data can monitor the patient's responses and the ventilator-patient interaction, which may provide objective criterion to ventilator setting.

Spatio-temporal distribution of micropropagules of green algae along the Jiangsu coast.

We conducted continuous monitoring at 13 stations along the Jiangsu coast to study the spatiotemporal distribution, population succession of micropropagules of green algae, and their impact on the outbreak of Southern Yellow Sea green tide. The study discovered that: 1) Green algae micropropagules had obvious temporal and spatial distribution and population changes along the Jiangsu coast. The monthly average abundance of micropropagules of green algae at station BH1, which was the high-value area, was 1230 inds/L. Station XS2 had the second-highest value area. Green algae micropropagules had an average monthly abundance of 836 inds/L. Between stations XS2 and BH1, the amount of green algae micropropagules steadily declined in comparison to other stations. The abundance was greatest from spring to early summer, and Ulva prolifera micropropagules predominated; 2) Compared with salinity, temperature had a more obvious effect on the micropropagules of green algae along the Jiangsu coast; 3) Green algae micropropagules on the Jiangsu coast could be a potential additional source on the outbreak of Southern Yellow Sea green tide. More data are needed to corroborate this conclusion. For the purpose of preventing and managing green tide, it is crucial to investigate the Southern Yellow Sea's potential supplementary source. This study analyzes the spatiotemporal distribution and population changes of green algae micropropagules along the Jiangsu coast, as well as their impact on green tide outbreaks, providing scientific data support for the prevention and control of green tides in the Southern Yellow Sea.

Mixed acid treatment for removal of green macroalgae from Neopyropia aquaculture nets: Field experiment in the Subei Shoal, China.

To develop an effective method to eliminate green macroalgae attached to Neopyropia aquaculture nets, we explored the influence of mixed acid solution on the photosynthetic fluorescence characteristics of Ulva spp. (green macroalgae) and Neopyropia yezoensis (red macroalgae) from Dafeng and Rudong aquaculture areas in Jiangsu Province, China. Treatment with mixed acid solution (0.0475 % hydrochloric acid:citric acid (pH 2.0) at a ratio of 4:3) for 60 s caused death of Ulva spp., but did not affect N. yezoensis. Additionally, a mixed acid solution effectively eliminated green macroalgae from Neopyropia aquaculture rafts and the marine environment remained unaffected. Hence, the application of mixed acid solution treatment has demonstrated significant efficacy in eradicating green macroalgae adhered to Neopyropia aquaculture rafts, thus presenting a promising strategy for mitigating green macroalgae proliferation in Neopyropia aquaculture areas and curbing their contribution to green tides.

Revolutionizing early-stage green tide monitoring: eDNA metabarcoding insights into Ulva prolifera and microecology in the South Yellow Sea.

Green tides, characterized by excessive Ulva prolifera blooms, pose significant ecological and economic challenges, especially in the South Yellow Sea. We successfully employed 18S environmental DNA (eDNA) metabarcoding to detect Ulva prolifera micropropagules, confirming the technique's reliability and introducing a rapid green tide monitoring method. Our investigation revealed notable disparities in the eukaryotic microbial community composition within Ulva prolifera habitats across different regions. Particularly, during the early stages of the South Yellow Sea green tide outbreak, potential interactions emerged between Ulva prolifera micropropagules and certain previously undocumented microorganisms from neighboring waters. These findings enhance our comprehension of early-stage green tide ecosystem dynamics, underscoring the value of merging advanced molecular techniques with conventional ecological methods to gain a comprehensive understanding of the impact of green tide on the local ecosystem. Overall, our study advances our understanding of green tide dynamics, offering novel avenues for control, ecological restoration, and essential scientific support for sustainable marine conservation and management.

Review of Allelopathy in Green Tides: The Case of Ulva prolifera in the South Yellow Sea.

The proliferation of large green macroalgae in marine environments has led to the occurrence of green tides, particularly in the South Yellow Sea region of China, where Ulva prolifera has been identified as the primary species responsible for the world's largest green tide events. Allelopathy among plants is a critical factor influencing the dynamics of green tides. This review synthesizes previous research on allelopathic interactions within green tides, categorizing four extensively studied allelochemicals: fatty acids, aldehydes, phenols, and terpenes. The mechanisms by which these compounds regulate the physiological processes of green tide algae are examined in depth. Additionally, recent advancements in the rapid detection of allelochemicals are summarized, and their potential applications in monitoring green tide events are discussed. The integration of advanced monitoring technologies, such as satellite observation and environmental DNA (eDNA) analysis, with allelopathic substance detection is also explored. This combined approach addresses gaps in understanding the dynamic processes of green tide formation and provides a more comprehensive insight into the mechanisms driving these phenomena. The findings and new perspectives presented in this review aim to offer valuable insights and inspiration for researchers and policymakers.

A bibliometric review of Green Tide research between 1995-2023.

In recent years, the frequent occurrence of green tides has attracted attention from academia and industry. Despite some literature reviews, systematic bibliometric and visualization analyses are still lacking. The study employs CiteSpace and VOSviewer tools to conduct a bibliometric and visualization analysis of green tide-related literature from the Web of Science (1995 to 2023). The study identifies key countries, institutions, journals, disciplines, and authors, and maps out their collaborative networks. Co-citation analysis provides an initial overview of various aspects within the green tide field. Keyword analysis has reveals six core themes: remote sensing applications, eutrophication and green tides, phylogenetic analysis, the impact of climate change, green tide management and applications, and studies focused on green tides in the China Sea. Additionally, keyword burst analysis has revealed two emerging trends. This study provides a strategic framework for future research, serving as a navigational guide in the field of green tide studies.

Spatiotemporal dynamics of bacterioplankton communities in the estuaries of two differently contaminated coastal areas: Composition, driving factors and ecological process.

Seasonal variations of environmental parameters usually lead to considerable changes in microbial communities. Nevertheless, the specific response patterns of these communities in coastal areas subjected to different levels of contamination remain unclear. Our results revealed notable fluctuations in the bacterioplankton community both seasonally and spatially, with seasonal variations being particularly significant. The diversity and composition of bacterioplankton communities in the estuaries varied significantly across seasons and between seas. Some bacterial phyla that were highly abundant in the dry season (e.g., Patescibacteria and Epsilonbacteraeota) were almost absent in the wet season. Furthermore, the network analysis revealed that the bacterioplankton networks were more complex during the wet season than in the dry season. In the wet season, the estuarine bacterioplankton network in the Yellow Sea region was more complex and stable, while the opposite was true in the dry season. According to the neutral community model, stochastic processes played a more significant role in the formation of bacterioplankton communities during the wet season than during the dry season. Estuarine bacterioplankton communities in the Yellow Sea region were more affected by stochastic processes compared to those in the Bohai Sea. In summary, in the estuaries of two differently contaminated coastal areas, the seasonal increase in nutrient levels enhanced the deterministic processes and network complexity of the bacterioplankton communities.

Overwintering and summer survival of Ulva prolifera in sediments: Indoor simulation of temperature impacts.

Green tides, a globally prevalent marine ecological anomaly observed in coastal regions, have received substantial attention. However, there is limited research on the burial of Ulva prolifera in sediments during the late stages of green tide outbreaks. This study investigates the effect of temperature on U. prolifera buried in sediment over 30 days. The measurements included the length, biomass, relative growth rate, chlorophyll composition and maximum quantum yield (Fv/Fm) of PS II at different stages. The results indicate that at -20 °C, numerous seedlings emerged after 14 days of recovery culture, suggesting the release of spores or gametes; survival was possible from -2 °C to 15 °C; but at 20 °C and 30 °C, all U. prolifera died. The U. prolifera buried in sediment during the late stage of green tide outbreaks may serve as one of the sources for the subsequent year's green tide eruption. This research provides insights into the origins of green tide outbreaks in the southern Yellow Sea.

Responses of photosynthesis-related genes in Sargassum horneri to high temperature stress.

Golden tide outbreak threatened the marine ecological environment. Sargassum horneri is a single dominant species of the Yellow Sea golden tide, which growth and development are affected by changes in sea water temperature. This study investigated the photosynthetic physiology of copper algae and found that the growth rate, chlorophyll a content, carotenoid content, Fv/Fm, and maximum electron transfer efficiency were significantly reduced, indicating that Sargassum horneri was under stress under high temperature. In this study, high-throughput sequencing was used to analyze the response mechanisms of photosynthesis-related genes in S. horneri under high temperature stress. The results showed that most of the photosynthesis-related genes in S. horneri were downregulated and photosynthesis was inhibited under high temperature stress. However, the expression levels of ferredoxin, ferredoxin-NADP reductase, light-harvesting protein complexes, and oxygen-evolving complex genes were significantly upregulated (P ≤ 0.05) after five days of high temperature treatment. This study found that photosynthesis related genes play a crucial role in regulating the photosynthetic response of S. horneri to high temperature stress.

Temporal succession of micropropagules during accumulation and dissipation of green tide algae: A case study in Rudong coast, Jiangsu Province.

Over the past 18 years, green tides have persistently occurred in the Yellow Sea. Micropropagules of these algae are key to bloom formation, yet their species composition and succession during dissipation remain underexplored. During the dissipation process of accumulated green tide algae, a large number of micropropagules are released. This study monitored the dissipation of green tide algae at a coastal site, tracking micropropagules in water and sediment using an internal transcribed spacer (ITS) and 5S rDNA primers. Results showed that the dissipation lasted about one month, with significant micropropagule release. Initially, micropropagules matched 5S-II Ulva prolifera, but later species like Ulva torta, Ulva simplex, Ulva flexuosa, and Ulva meridionalis emerged. Ulva meridionalis dominated sediment in July and August, while U. torta was prevalent in water, and U. flexuosa was dominant in other months. Accumulated U. prolifera in the intertidal zone may not contribute to the seeding of the next year's bloom. This study sheds light on the dissipation process and succession patterns of micropropagules in coastal environments.

Tungsten-needle intensifies microwave-sustained plasma accelerating direct H2S conversion to H2.

Direct sustainable conversion of hydrogen sulfide (H2S) enables collaborative recovery of H and S resources via a metal-enhanced microwave plasma strategy, avoiding the hydrogen waste in the traditional Claus process. However, the metal size effect on microwave plasma property, the optimal process parameters, and the enhancement mechanism remain unclear in H2S conversion. Herein, the optimal tungsten needle (diameter: 1 mm, length: 60 mm, and tip angle: 10°) is experimentally proven for intensifying microwave discharge in multi-mode cavities. Theoretical calculations and plasma distribution reveal that the optimized tungsten needle achieves the ideal coupling with the microwave field, exhibiting extreme electric field augmentation around the needle tip. Tungsten-needle intensifies microwave-sustained plasma, realizing 40.2 % (90.1 %) conversion of 100 % (10 %) concentration H2S to H2 at a low microwave power of 300 W with a good stability of 30 hrs. Low power, large flow rate, and high H2S concentration are beneficial for improving energy efficiency. The excitation of microwave plasma is accompanied by a massive generation of highly energetic electrons. The direct high-energy electron-H2S collision contributes a lot to H2S splitting, especially for high-concentration H2S. In-situ optical emission spectroscopy confirms the vital S and H radicals in the plasma. The free radical reactions triggered by electron collisions are responsible for the production of H2 and S. This work opens an avenue to sustainable and low-carbon hydrogen production from the direct conversion and utilization of H2S.

Analysis of the potential of marine bioblue carbon storage and their regional contributions in Shanghai marine areas.

Shanghai's extensive coastline and offshore marine areas feature diverse ecosystems. This study aimed to determine the current status, spatial distribution, and total capacity of marine carbon storage in Shanghai. Surveys were conducted on oyster reefs, phytoplankton, and fish populations from August to November 2022, with samples collected to quantify biomass and carbon content. The carbon storage of oyster reefs, phytoplankton, and fish was found to be 2.045 × 105 tC, 5113.19 kgC, and 56.6014 tC, respectively. The spatial distributions exhibited significant heterogeneity, influenced by substrate type, nutrient concentrations, and fishing activities. The total marine carbon storage capacity in Shanghai's offshore waters was estimated at 2.045 × 105 tC, highlighting a pathway for achieving regional carbon neutrality goals. This study enriches baseline data, elucidates carbon sequestration functions and spatial patterns, and provides scientific support for marine ecological protection and blue carbon resource utilization. Future research should investigate spatiotemporal variation mechanisms and potential regulation pathways.

Mechanisms of harmful effects of Microcystis aeruginosa on a brackish water organism Moina mongolica based on physiological and transcriptomic responses.

To investigate the detrimental impacts of cyanobacterial bloom, specifically Microcystis aeruginosa, on brackish water ecosystems, the study used Moina mongolica, a cladoceran species, as the test organism. In a chronic toxicology experiment, the survival and reproductive rates of M. mongolica were assessed under M. aeruginosa stress. It was observed that the survival rate of M. mongolica fed with M. aeruginosa significantly decreased with time and their reproduction rate dropped to zero, while the control group remained maintained stable and normal reproduction. To further explore the underlying molecular mechanisms of the effects of M. aeruginosa on M. mongolica, we conducted a transcriptomic analysis on newly hatched M. mongolica cultured under different food conditions for 24 h. The results revealed significant expression differences in 572 genes, with 233 genes significantly up-regulated and 339 genes significantly down-regulated. Functional analysis of these differentially expressed genes identified six categories of physiological functional changes, including nutrition and metabolism, oxidative phosphorylation, neuroimmunology, cuticle and molting, reproduction, and programmed cell death. Based on these findings, we outlined the basic mechanisms of microcystin toxicity. The discovery provides critical insights into the mechanisms of Microcystis toxicity on organisms and explores the response mechanisms of cladocerans under the stress of Microcystis.