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Background: Previous research has shown that combining tyrosine kinase inhibitors (TKIs) with immunotherapy results in synergistic clinical efficacy. Cadonilimab, the first approved bi-specific antibody targeting PD-1 and CTLA-4, was studied to evaluate its efficacy and safety in combination with Lenvatinib as a first-line treatment for patients with unresectable hepatocellular carcinoma (uHCC). Methods: A retrospective study was conducted on 29 uHCC patients diagnosed at Nanfang Hospital, Southern Medical University, between July 7, 2022, and March 3, 2023. Patients received Cadonilimab (10 mg/kg, IV, every 3 weeks) combined with Lenvatinib (8 mg, orally, daily). The primary endpoint was the objective response rate (ORR), with secondary endpoints including disease control rate (DCR), median progression-free survival (mPFS), median overall survival (mOS), median time to progression (mTTP), and safety. Results: By April 2023, 29 patients had been enrolled in the study. The ORR was 37.9 %, DCR was 82.8 %, mPFS was 8.1 months, mTTP was 8.2 months, and mOS was not reached. A total of 93.1 % of patients experienced at least one treatment-related adverse event (TRAE). The most common adverse events were weight loss (51.7 %), increased aspartate aminotransferase (48.3 %), leukocytopenia (48.3 %), and neutropenia (48.3 %). TRAEs of grade 3 or higher occurred in 51.7 % of patients, with no grade 4 TRAEs observed. Conclusion: This study demonstrated the efficacy and safety of this combination, potentially improving outcomes as a first-line therapy, and offering a novel therapeutic approach for advanced HCC.
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Heat shock protein 40 belonging to heat shock protein family plays an important role in the immune responses of organisms. In this study, the full length cDNA of Hsp40 was 2426 bp including a 1368 bp open reading frame (ORF) encoding 455 amino acids with a molecular weight of 49.16 kDa and a theoretical isoelectric point of 9.34 in blood parrot Vieja synspila â × Amphilophus citrinellus â, an important ornamental fish in China. It had three conserved domains DnaJ, CRR and DnaJ_C. Phylogenetic analysis showed that the sequence of Hsp40 among species was conserved, and the blood parrot Hsp40 was closely related to Neolamprologus brichardi. Blood parrot Hsp40 mRNA could be detected in all of the tissues examined and mainly distributed in the cytoplasm. The expression of Hsp40 was upregulated during lipopolysaccharide (LPS) challenge. Upregulated Hsp40 inhibited the activity of nuclear factor κB (NF-κB) and activated protein 1 (AP-1) and reduced the ratio of Bax/Bcl-2 mRNA expression. This study provides a theoretical basis for further exploring the role of Hsp40 gene in the anti-bacterial immunity of blood parrot.
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The fluorescence collection from single atoms and emitters has been extensively utilized in quantum information and quantum optics research. Here, we investigated the collection efficiency of an objective lens by drawing an analogy between the free-space beam (FSB) and a waveguide mode. We explored how efficiency is influenced by their thermal motion within a dipole trap. Furthermore, we introduce an effective energy fraction ratio to quantify potential imperfections in the focusing of the objective lens. Our results provide valuable insights for optimizing the fluorescence collection in single-atom experiments and highlight the importance of considering realistic experimental conditions when estimating achievable efficiencies.
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BACKGROUND: Accumulating evidence suggests that the inflammatory cytokine interleukin-6 (IL-6) contributes to the pathophysiology of psychiatric disorders. However, there was no study concerning the relationship between IL-6 concentrations and clinical features in the chronic phase of early-onset schizophrenia (EOS). AIM: To investigate the relationship between serum IL-6 concentration and the clinical features of EOS. METHODS: We measured serum IL-6 Levels from 74 patients with chronic schizophrenia, including 33 with age at onset < 21 years (EOS group) and 41 with onset ≥ 21 years in [adult-onset schizophrenia (AOS) group], and from 41 healthy controls. Symptom severities were evaluated using the Positive and Negative Syndrome Scale (PANSS). RESULTS: Serum IL-6 concentrations were higher in both EOS and AOS groups than healthy controls (F = 22.32, P < 0.01), but did not differ significantly between EOS and AOS groups (P > 0.05) after controlling for age, body mass index, and other covariates. Negative symptom scores were higher in the EOS group than the AOS group (F = 6.199, P = 0.015). Serum IL-6 concentrations in the EOS group were negatively correlated with both total PANSS-negative symptom score (r = -0.389, P = 0.032) and avolition/asociality subscore (r = -0.387, P = 0.026). CONCLUSION: Patients with EOS may have more severe negative symptoms than those with adult-onset schizophrenia during the chronic phase of the illness. IL-6 signaling may regulate negative symptoms and its avolition/asociality subsymptoms among the early-onset chronic schizophrenic patients.
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Introduction: The correlation between potassium and nonalcoholic fatty liver disease (NAFLD) is currently still poorly understood. We conducted this study to explore the correlation between dietary potassium intake and NAFLD, as well as advanced hepatic fibrosis (AHF). The study also sought to identify any potential interactions. Methods: The data employed in this study were obtained from the National Health and Nutrition Examination Survey (NHANES) program, encompassing a period from 2007 to 2018. Employing the multiple logistic regression analysis, we evaluated the association of dietary potassium intake with NAFLD and AHF. Subsequently, stratification analysis, based on demographic variables, was constructed so as to assess the stability of the results. In addition, potential interaction effects were assessed by interaction tests. Results: A total of 9443 participants were included in the analysis. The mean age of the participants was 50.4 years, and their daily mean dietary potassium and vitamin C intake was 2556.49 mg and 82.93 mg, respectively. Following comprehensive statistical analyses, the findings indicated a negative correlation between dietary potassium intake and both NAFLD and AHF. Participants in Q4 group with dietary potassium intake exhibited a 31% and 42% reduction in the odds of developing NAFLD and AHF, respectively, in comparison to Q1 group. An interaction effect of dietary vitamin C intake was observed in the association between dietary potassium intake and NAFLD. The results imply that high dietary vitamin C intake augment the inverse relationship between dietary potassium intake and NAFLD. Conclusion: Dietary potassium intake was found to have an inverse association with the odds of both NAFLD and AHF. The association between dietary potassium intake and NAFLD was amplified by the presence of vitamin C in the diet.
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Glutathione (GSH) is an important antioxidant that is generated and degraded via the GSH cycle. Quantification of the main components in the GSH cycle is necessary to evaluate the process of GSH. In this study, a robust ultra-performance liquid chromatography-tandem mass spectrometry method for the simultaneous quantification of 10 components (GSH; γ-glutamylcysteine; cysteinyl-glycine; n-acetylcysteine; homocysteine; cysteine; cystine; methionine; glutamate; pyroglutamic acid) in GSH cycle was developed. The approach was optimized in terms of derivative, chromatographic, and spectrometric conditions as well as sample preparation. The unstable thiol groups of GSH, γ-glutamylcysteine, cysteinyl-glycine, n-acetylcysteine, cysteine, and homocysteine were derivatized by n-ethylmaleimide. The derivatized and underivatized analytes were separated on an amino column with gradient elution. The method was further validated in terms of selectivity (no interference), linearity (R2 > 0.99), precision (% relative standard deviation [RSD%] range from 0.57 to 10.33), accuracy (% relative error [RE%] range from -3.42 to 10.92), stability (RSD% < 5.68, RE% range from -2.54 to 4.40), recovery (RSD% range from 1.87 to 7.87) and matrix effect (RSD% < 5.42). The validated method was applied to compare the components in the GSH cycle between normal and oxidative stress cells, which would be helpful in clarifying the effect of oxidative stress on the GSH cycle.
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Glutationa , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Glutationa/análise , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Homocisteína/análise , Cisteína/análise , Ácido Pirrolidonocarboxílico/análise , Ácido Pirrolidonocarboxílico/química , Ácido Pirrolidonocarboxílico/metabolismo , Dipeptídeos/análise , Acetilcisteína/análise , Acetilcisteína/química , Cistina/análiseRESUMO
Zearalenone (ZEN) has been shown to cause reproductive damage by inducing oxidative stress. Astaxanthin and L-carnitine are widely used to alleviate oxidative stress and promote sperm maturation. However, it remains uncertain whether they are effective in mitigating spermatogenesis disorders induced by ZEN. This study aimed to investigate the therapeutic efficacy and potential mechanisms of Vigor King (Vig), a compound preparation primarily consisting of astaxanthin and L-carnitine, in alleviating ZEN-induced spermatogenesis disorders. In the experiment, mice received continuous oral gavage of ZEN (80⯵g/kg) for 35 days, accompanied by a rescue strategy with Vig (200â¯mg/kg). The results showed that Vig effectively reduced the negative impact on semen quality and improved the structural and functional abnormalities of the seminiferous epithelium caused by ZEN. Additionally, the accumulation of reactive oxygen species (ROS), DNA double-strand breaks, apoptosis, and autophagy abnormalities were all significantly ameliorated. Intriguingly, the GSK3ß-dependent BTRC-NRF2 signaling pathway was found to play an important role in this process. Furthermore, testing of offspring indicated that Vig could extend its protective effects to the next generation, effectively combating the transgenerational toxic effects of ZEN. In summary, our research suggests that Vig supplementation holds considerable promise in alleviating spermatogenesis disorders induced by zearalenone.
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Espermatogênese , Zearalenona , Animais , Zearalenona/toxicidade , Masculino , Espermatogênese/efeitos dos fármacos , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Carnitina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Estrogênios não Esteroides/toxicidade , Feminino , XantofilasRESUMO
BACKGROUND: Toxoplasma gondii is an intracellular protozoan parasite that is widely distributed in humans and warm-blooded animals. T. gondii chronic infections can cause toxoplasmic encephalopathy, adverse pregnancy, and male reproductive disorders. In male reproduction, the main function of the testis is to provide a stable place for spermatogenesis and immunological protection. The disorders affecting testis tissue encompass abnormalities in the germ cell cycle, spermatogenic retardation, or complete cessation of sperm development. However, the mechanisms of interaction between T. gondii and the reproductive system is unclear. The aims were to study the expression levels of genes related to spermatogenesis, following T. gondii infection, in mouse testicular tissue. METHODS: RNA-seq sequencing was carried out on mouse testicular tissues from mice infected or uninfected with the T. gondii type II Prugniaud (PRU) strain and validated in combination with real-time quantitative PCR and immunofluorescence assays. RESULTS: The results showed that there were 250 significant differentially expressed genes (DEGs) (P < 0.05, |log2fold change| ⧠1). Bioinformatics analysis showed that 101 DEGs were annotated to the 1696 gene ontology (GO) term. While there was a higher number of DEGs in the biological process classification as a whole, the GO enrichment revealed a significant presence of DEGs in the cellular component classification. The Arhgap18 and Syne1 genes undergo regulatory changes following T. gondii infection, and both were involved in shaping the cytoskeleton of the blood-testis barrier (BTB). The number of DEGs enriched in the MAPK signaling pathway, the ERK1/2 signaling pathway, and the JNK signaling pathway were significant. The PTGDS gene is located in the Arachidonic acid metabolism pathway, which plays an important role in the formation and maintenance of BTB in the testis. The expression of PTGDS is downregulated subsequent to T. gondii infection, potentially exerting deleterious effects on the integrity of the BTB and the spermatogenic microenvironment within the testes. CONCLUSIONS: Overall, our research provides in-depth insights into how chronic T. gondii infection might affect testicular tissue and potentially impact male fertility. These findings offer a new perspective on the impact of T. gondii infection on the male reproductive system.
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Testículo , Toxoplasma , Toxoplasmose Animal , Transcriptoma , Animais , Masculino , Camundongos , Testículo/parasitologia , Testículo/metabolismo , Toxoplasma/genética , Toxoplasmose Animal/parasitologia , Espermatogênese/genética , Perfilação da Expressão Gênica , Doença Crônica , Biologia ComputacionalRESUMO
BACKGROUND: With the improvements in laparoscopic or robotic surgical techniques and instruments, a growing number of surgeons have attempted to complete all digestive tract reconstruction intracorporeally; these procedures include totally robotic gastrectomy (TRG) and totally laparoscopic gastrectomy (TLG). This study aimed to evaluate the safety and feasibility of the TRG and compare the short-term outcomes of the TRG and TLG in patients with gastric cancer. METHODS: Between January 2018 and June 2023, 346 consecutive patients who underwent TRG or TLG at a high-volume academic gastric cancer specialty center were included. 1:1 propensity score matching (PSM) was performed to reduce confounding bias. The surgical outcomes, postoperative morbidity, and surgical burden were compared in PSM cohort. RESULTS: After PSM, a well-balanced cohort of 194 patients (97 in each group) was included in the analysis. The total operation time of the TRG group was significantly longer than that of the TLG group (244.9 vs. 213.0 min, P < 0.001). There was no significant difference in the effective operation time between the 2 groups (217.8 vs. 207.2 min, P = 0.059). The digestive tract reconstruction time of the TRG group was significantly shorter than that of the TLG group (39.4 vs. 46.7 min, P < 0.001). The mean blood loss in the TRG group was less than that in the TLG group (101.1 vs. 126.8 mL, P = 0.014). The TRG group had more retrieved lymph nodes in the suprapancreatic area than that in the TLG group (16.6 vs 14.2, P = 0.002). The TRG group had a lower surgery task load index (38.9 vs. 43.1, P < 0.001) than the TLG group. No significant difference was found in terms of postoperative morbidity between the 2 groups (14.4% vs. 16.5%, P = 0.691). CONCLUSION: This study demonstrated that TRG is a safe and feasible procedure, and is preferable to TLG in terms of invasion and ergonomics. The TRG may maximize the superiority of robotic surgical systems and embodies the theory of minimally invasive surgery.
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Gastrectomia , Laparoscopia , Duração da Cirurgia , Pontuação de Propensão , Procedimentos Cirúrgicos Robóticos , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Gastrectomia/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Laparoscopia/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Estudos de Viabilidade , Resultado do Tratamento , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologiaRESUMO
INTRODUCTION: Sulfur-fumigation of Paeoniae Radix Alba (PRA) could induce the chemical transformation of its bioactive component paeoniflorin into a sulfur-containing derivative paeoniflorin sulfite, and thus alter the quality, bioactivities, pharmacokinetics, and toxicities of PRA. However, how sulfur-fumigated PRA (S-PRA) affects the quality of PRA-containing complex preparations has not been intensively evaluated. OBJECTIVES: We intend to evaluate the influence of S-PRA on the overall quality of three kinds of Si-Wu-Tang (SWT) formulations, i.e., decoction (SWT-D), granule (SWT-G), and mixture (SWT-M). MATERIAL AND METHODS: An UPLC-DAD multi-components quantification method was used to compare the transfer rates of paeoniflorin sulfite and other 10 bioactive components between S-PRA-containing and NS-PRA-containing SWT formulations. An UPLC-QTOF-MS/MS-based target metabolomics approach was applied to explore the differential sulfur-containing derivatives in S-PRA-containing SWT formulations. RESULTS: The transfer rates of paeoniflorin sulfite in three S-PRA-containing SWT formulations were all higher than 100%. Moreover, S-PRA also increased the transfer rate of 5-hydroxymethylfurfural, 1,2,3,4,6-O-pentagalloylglucose, whereas decreased that of paeoniflorin, albiflorin, and ferulic acid in three SWT formulations. Six pinane monoterpene glucoside sulfites originally identified in S-PRA, were also detectable in three S-PRA-containing SWT formulations. In addition, seven phenolic acid sulfites including (3Z)-6-sulfite-ligustilide, (3E)-6-sulfite-ligustilide, 6,8-disulfite-ligustilide, ferulic acid sulfite, neochlorogenic acid sulfite, chlorogenic acid sulfite, and angelicide sulfite (or isomer) were newly identified in these three S-PRA-containing formulations. CONCLUSION: S-PRA could differentially affect the transfer rate of paeoniflorin sulfite and other bioactive components during the preparation of three SWT formulations and subsequently the overall quality thereof.
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Medicamentos de Ervas Chinesas , Fumigação , Paeonia , Enxofre , Espectrometria de Massas em Tandem , Paeonia/química , Medicamentos de Ervas Chinesas/química , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Enxofre/química , Fumigação/métodos , Glucosídeos/química , Monoterpenos/química , Metabolômica/métodosRESUMO
As an emerging additive manufacturing technology, inkjet printing has been increasingly applied in microelectronics field. However, due to the impacting and rebounding behaviors of conductive ink droplets impinging onto flat substrates, it is challenging to fabricate conductive lines with desired quality, such as suitable line width and line thickness, and matching resistance when it is used for interconnecting multifarious electronic components if there is not a proper configuration of operating parameters. To address this research gap, this article aims to investigate the effect of process parameters on the quality of conductive lines, including the platform temperature, printing speed, number of layers, and delay time (droplet interarrival time), are selected to conduct a full factorial experiment. First, the approximate parameter ranges for ensuring the continuity of conductive lines are determined. Second, this study analyzes the interactive effect among process parameters on line quality. Third, an artificial neural network (ANN) is constructed to predict the quality of printed lines. Results show that the line width does not increase with an increased number of layers, while the line thickness shows an increasing trend. The low resistance and high aspect ratio of printed line are achieved by printing 5 layers with the platform temperature of 70°C, the delay time of 12.2 ms, and the printing speed of 1139.39 mm/min. Moreover, the ANN model can be used to predict line width and line thickness with excellent performance, except for the resistance due to the irregular line edge. This study provides a useful guide for the selection of appropriate printing parameters to realize a diverse range of quality properties for 3D printed conductive lines in integrated circuits.
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Background: This study assessed clinical outcomes of three-dimensional-printed template (3DPT)-guided radioactive seed brachytherapy (RSBT) via a submental approach for recurrent base of tongue and floor of mouth cancer. Methods: Thirty-one patients with recurrent lingual and floor of mouth squamous cell carcinoma after surgery and radiotherapy were treated with 3DPT-guided RSBT from 2015 to 2022. Seeds were implanted through a submental approach guided by 3DPTs. Local control (LC), overall survival (OS), disease control (DC) and quality of life (QOL) were evaluated. Results: The median follow-up was 13.7 months. The 1-, 3- and 5-year LC rates were 66.1%, 66.1%, and 55.1% respectively. The 1-, 3- and 5-year OS rates were 63.4%, 33.4%, and 8.3%. The 1-, 3- and 5-year DC rates were 37.8%, 26.5%, and 21.2%. Univariate analysis showed tumor size significantly affected LC (P = 0.031). The presence of extraterritorial lesions affected DC and OS on multivariate analysis (P < 0.01). QOL improved significantly in domains of pain, swallowing, chewing, taste, and emotion after treatment compared to baseline. Four patients (13%) developed necrosis and osteoradionecrosis. Conclusions: 3DPT-guided submental RSBT provided favorable LC and QOL for recurrent tongue/floor of mouth cancer with minimal toxicity; moreover, severe toxicity should be noted.
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P/TGMS (Photo/thermo-sensitive genic male sterile) lines are crucial resources for two-line hybrid rice breeding. Previous studies revealed that slow development is a general mechanism for sterility-fertility conversion of P/TGMS in Arabidopsis. However, the difference in P/TGMS genes between rice and Arabidopsis suggests the presence of a distinct P/TGMS mechanism in rice. In this study, we isolated a novel P/TGMS line, ostms19, which shows sterility under high-temperature conditions and fertility under low-temperature conditions. OsTMS19 encodes a novel pentatricopeptide repeat (PPR) protein essential for pollen formation, in which a point mutation GTA(Val) to GCA(Ala) leads to ostms19 P/TGMS phenotype. It is highly expressed in the tapetum and localized to mitochondria. Under high temperature or long-day photoperiod conditions, excessive ROS accumulation in ostms19 anthers during pollen mitosis disrupts gene expression and intine formation, causing male sterility. Conversely, under low temperature or short-day photoperiod conditions, ROS can be effectively scavenged in anthers, resulting in fertility restoration. This indicates that ROS homeostasis is critical for fertility conversion. This relationship between ROS homeostasis and fertility conversion has also been observed in other tested rice P/TGMS lines. Therefore, we propose that ROS homeostasis is a general mechanism for the sterility-fertility conversion of rice P/TGMS lines.
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Fertilidade , Homeostase , Oryza , Infertilidade das Plantas , Proteínas de Plantas , Pólen , Espécies Reativas de Oxigênio , Oryza/genética , Oryza/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fertilidade/genética , Pólen/genética , Pólen/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Infertilidade das Plantas/genética , Regulação da Expressão Gênica de Plantas , Temperatura , Luz , FotoperíodoRESUMO
Whether coexisting microplastics (MPs) affect the ecological and health risks of cadmium (Cd) in soils is a cutting-edge scientific issue. In this study, four typical Chinese soils were prepared as artificially Cd-contaminated soils with/without aged polystyrene (PS). TCLP and in vitro PBET model were used to determine the leachability (ecological risk) and oral bioaccessibility (human health risk) of soil Cd. The mechanisms by which MPs influence soil Cd were discussed from direct and indirect perspectives. Results showed that there was no significant difference in the leachability of soil Cd with/without aged PS. Additionally, aged PS led to a significant decrease in the bioaccessibility of soil Cd in gastric phase, but not in small intestinal phase. The increase in surface roughness and the new characteristic peaks (e.g., Si-O-Si) of aged PS directly accounted for the change in Cd bioaccessibility. The change in organic matter content indirectly accounted for the exceptional increase in Cd bioaccessibility of black soil with aged PS in small intestinal phase. Furthermore, the changes in cation exchange capacity and Cd mobility factor caused by aged PS explained the change in Cd leachability. These results contribute to a deeper understanding about environmental and public health in complicated emerging scenarios.
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Cádmio , Poluentes do Solo , Humanos , Idoso , Cádmio/toxicidade , Cádmio/análise , Microplásticos/toxicidade , Plásticos , Poliestirenos/toxicidade , Solo , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Disponibilidade BiológicaRESUMO
Ultraviolet (UV) light is widely used for wastewater disinfection. Traditional electrode-excited UV lamps, such as low-pressure mercy lamps (LPUV), encounter drawbacks like electrode aging and rapid light attenuation. A novel UV source of microwave discharge electrodeless lamp (MDEL) has aroused attention, yet its disinfection performance is unclear and still far from practical application. Here, we successfully developed a complete piece of equipment based on MDELs and achieved the application for disinfection in wastewater treatment plants (WWTPs). The light emitted by an MDEL (MWUV) shared a spectrum similar to that of LPUV, with the main emission wavelength at 254 nm. The inactivation rate of Gram-negative E. coli by MWUV reached 4.5 log at an intensity of 1.6 mW/cm2 and a dose of 20 mJ/cm2. For Gram-positive B. subtilis, an MWUV dose of 50 mJ/cm2 and a light intensity of 1.2 mW/cm2 reached an inactivation rate of 3.4 log. A higher MWUV intensity led to a better disinfection effect and a lower photoreactivation rate of E. coli. When inactivated by MWUV with an intensity of 1.2 mW/cm2 and a dose of 16 mJ/cm2, the maximum photoreactivation rate and reactivation rate constant Kmax of E. coli were 0.63 % and 0.11 % h-1 respectively. Compared with the photoreactivation, the dark repair of E. coli was insignificant. The full-scale application of the MDEL equipment was conducted in two WWTPs (10,000 m3/d and 15,000 m3/d). Generally 2-3 log inactivation rates of fecal coliforms in secondary effluent were achieved within 5-6 s contact time, and the disinfected effluent met the emission standard (1000 CFU/L). This study successfully applied MDEL for disinfection in WWTPs for the first time and demonstrated that MDEL has broad application prospects.
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Desinfecção , Águas Residuárias , Escherichia coli , Raios Ultravioleta , Micro-OndasRESUMO
PURPOSE: This study seeks to evaluate the ability of the updated stress strain index (SSIv2) and other Corvis ST biomechanical parameters in distinguishing between keratoconus at different disease stages and normal eyes. DESIGN: Diagnostic accuracy analysis to distinguish disease stages. METHODS: 1084 eyes were included and divided into groups of normal (199 eyes), forme fruste keratoconus (FFKC, 194 eyes), subclinical keratoconus (SKC, 113 eyes), mild clinical keratoconus (CKC-â , 175 eyes), moderate clinical keratoconus (CKC-â ¡, 204 eyes), and severe clinical keratoconus (CKC-â ¢, 199 eyes). Each eye was subjected to a Corvis ST examination to determine the central corneal thickness (CCT), biomechanically corrected intraocular pressure (bIOP), SSIv2 (updated stress-strain index), and other 8 Corvis parameters including the stress-strain index (SSIv1), stiffness parameter at first applanation (SP-A1), first applanation time (A1T), Ambrósio relational thickness to the horizontal profile (ARTh), integrated inverse radius (IIR), maximum deformation amplitude (DAM), ratio between deformation amplitude at the apex and at 2 mm nasal and temporal (DARatio2), and Corvis biomechanical index (CBI). The sensitivity and specificity of these parameters in diagnosing keratoconus were analyzed through receiver operating characteristic curves. RESULTS: Before and after correction for CCT and bIOP, SSIv2 and ARTh were significantly higher and IIR and CBI were significantly lower in the normal group than in the FFKC group, SKC group and the 3 CKC groups (all P < .05). There were also significant correlations between the values of SSIv2, ARTh, IIR, CBI, and the CKC severity (all P < .05). AUC of SSIv2 was significantly higher than all other Corvis parameters in distinguishing normal eyes from FFKC, followed by IIR, ARTh and CBI. CONCLUSION: Corvis ST's updated stress-strain index, SSIv2, demonstrated superior performance in differentiating between normal and keratoconic corneas, and between corneas with different keratoconus stages. Similar, but less pronounced, performance was demonstrated by the IIR, ARTh and CBI.