First Report of Aspergillus westerdijkiae Causing Leaf Blight on Rehmannia glutinosa in China.

Rehmannia glutinosa (also known as Chinese foxglove) is a perennial dicotyledonous herb, which plays an important role in traditional Chinese medicine. Its active ingredients have a wide range of pharmacological effects on the blood system, endocrine system, immune system, cardiovascular system, and nervous system (Zhang et al. 2008). In May 2022, leaf blight was observed on 45-day-old R. glutinosa in a seedling nursery in Jiaozuo City (35°01'44.20″N, 113°05'30.63″E), Henan Province, China with an approximate disease incidence up to 54% (~1,300 plants). Irregular brown lesion initially appeared on the tips of basal leaves, then progressed to the entire leaf causing leaf drying out (Supple. Fig. 1-A, B, C). The same symptoms appeared successively in the leaves from the base to the top of the plant, which eventually caused the whole plant to die. To identify the pathogen, eight symptomatic leaves were randomly collected from eight individual plants, and cut into small pieces (5 × 5 mm) at the border of lesions. The pieces were surface disinfected in 75% ethanol for 15 s, followed by 1% NaClO for 1 min, rinsed in sterile water three times, and placed on potato dextrose agar (PDA) medium in the dark for 3 days at 25℃. Finally, 12 purified isolates (DHY1-DHY12) were obtained by using single spore method. Leaves of R. glutinosa seedlings were inoculated with conidial suspension (106 conidia/ml), three plants were inoculated per isolate. Controls were treated with sterilized water. All inoculated and control plants were incubated in a greenhouse at 25℃ under 80 ± 10% humidity and a 8-h/16-h dark/light cycle. This experiment was repeated three times. After 5 days, similar symptoms to those of diseased leaves in the seedling nursery appeared on leaves inoculated with DHY4-DHY10, while plants inoculated with DHY1-DHY3, DHY11-DHY12, and the controls remained asymptomatic (Supple. Fig.1-D, E). The same fungi were re-isolated from diseased leaves, fulfilling Koch's postulates. The causal agents DHY4 to DHY10, showed similar morphology, which were morphologically identified as Aspergillus sp. (Visagie et al. 2014). Isolate DHY5 was selected for further study. On PDA plates, the colonies were covered with white velutinous mycelia (Supple. Fig.1-F). Conidia were ochre yellow and outwards concentric circles. Vesicles were globose, and about 20.1-26.6 µm in diameter (Supple. Fig.1-G). Conidiophore stipes were smooth walled and hyaline, with conidial heads radiating. The conidia were light yellow to orange, exudate clear to orange droplets. The conidia were (2.53-3.25) µm × (2.58-3.47) µm in diameter (n=50) (Supple. Fig.1-H). For further molecular identification, the ITS and TUB gene sequences were amplified with primer pairs ITS1/ITS4 and BT2a/BT2b (Glass and Donaldson. 1995), respectively. BLASTn searches of the ITS (PP355445) and TUB (PP382788) sequences showed 100% and 98.42% similarity to those of A. westerdijkiae (OP237108 and OP700424), respectively. Phylogenetic analysis based on the concatenated sequences of ITS and TUB confirmed that the fungus was A. westerdijkiae, (Supple. Fig.2). A. westerdijkiae was mainly reported on its secondary metabolite ochratoxin A contamination of agricultural products, fruits, and various food products, such as coffee beans (Alvindia et al 2016), grapes (Díaz et al. 2009), oranges and fruit juice (Marino et al. 2009), etc. To our knowledge, this is the first report of A. westerdijkiae causing leaf blight on R. glutinosa in China.

Green Nanopesticide: pH Response and Molybdenum Selenide Carrier with Photothermal Effect to Transport Prochloraz to Inhibit Sclerotinia Disease.

Accurate pesticide delivery is a key factor in improving pesticide utilization, which can effectively reduce the use of pesticides and environmental risks. In this study, we developed a nanocarrier preparation method which can be controlled by pH/near-infrared response. Mesoporous molybdenum selenide (MoSe2) with a high loading rate was used as the core, poly(acrylic acid) (PAA) with acid response was used as the shell, and prochloraz (Pro) was loaded to form a pH-/near-infrared-responsive core-shell nanosystem (Pro@MoSe2@PAA NPs, abbreviated as PMP). Sclerotinia sclerotiorum infection secretes oxalic acid, forming an acidic microenvironment. In an acidic environment, PMP could quickly release Pro, and the cumulative release amount of Pro at pH = 5.0 was 3.1 times higher than that at pH = 7.4, and the efficiency of releasing Pro in the acidic environment was significantly enhanced. In addition, the release rate of PMP under near-infrared light irradiation was also significantly improved, and the cumulative release of Pro under simulated sunlight was 2.35 times higher than that under no light. The contact angles of PMP droplets on rapeseeds were reduced by 31.2 and 13.9% compared to Pro and MoSe2, respectively, which proved that the nanosystems had good wettability. In addition, PMP shows excellent adhesion and resistance to simulated rain washout. In the plate antibacterial experiment, the inhibitory effect of 0.5 µg/mL PMP on S. sclerotiorum was as high as 75.2% after 6 days, which showed a higher bactericidal activity than Pro. More importantly, PMP shows excellent biocompatibility and safety to plants, microorganisms, and cells. In a word, PMP is a green nanopesticide with a dual response of pH/near-infrared light, which provides a new strategy for the sustainable development of agriculture.

Multifunctional Supramolecular Vesicles as Zn2+ -Triggered Microglial Modulator Alleviates Alzheimer's Disease.

Zn2+ -induced ß-amyloid protein (Aß) aggregation and microglia activation are the predominant contributors in Alzheimer's disease (AD). Regulating intracephalic excessive Zn2+ is a promising therapeutic strategy for AD treatment. However, only inhibition of Zn2+ is hardly to repair continuous damages caused by activated microglia. Herein, an intelligent resveratrol-loaded supramolecular vesicles (RES-loaded vesicles) with zinc ion chelation function and responsive release capability are constructed to alleviate Aß fibrillation, oxidative stress, and microglial dysfunction. The resveratrol encapsulation efficiency and drug loading efficiency are calculated to be 49.67% and 7.87%, respectively. In vitro studies demonstrate that the RES-loaded vesicles can modulate Zn2+ -dependent Aß aggregation. More importantly, the cargoes will be released in zinc environment and further reprograms microglia from proinflammatory M1 phenotype toward anti-inflammatory M2 phenotype, which prevents spontaneous neuroinflammation and alleviates cytotoxicity of cultured cells from 29% to 12%. With the stereotactic or intranasal administration, RES-loaded vesicles can overcome the blood brain barrier, alleviate neuronal apoptosis, neuroinflammation, and ultimately ameliorate cognitive impairment in two AD mouse models. This work provides a new sight for taking advantage of Zn2+ to treat CNS disorders.

Green Nanopesticide: pH-Responsive Eco-Friendly Pillar[5]arene-Modified Selenium Nanoparticles for Smart Delivery of Carbendazim to Suppress Sclerotinia Diseases.

Controlled-release delivery systems have been widely used to improve the efficacy and bioavailability of pesticides and minimize environmental risks. Herein, a fungicide carbendazim (CBZ)-loaded, a kind of nanovalve including trimethylammoniumpillar[5]arene (AP5), and methyl orange (MO)-functionalized mesoporous selenium (MSe) nanopesticides (CBZ@AP5/MSe⊃MO) were prepared. The nanovalve endowed CBZ@AP5/MSe⊃MO with a pH-responsive property, so the CBZ@AP5/MSe⊃MO can respond to the microenvironment of the pathogen Sclerotinia sclerotiorum (S. sclerotiorum). First, MO was shed due to protonation, and AP5-functionalized MSe gradually dissolved in an acid environment. Finally, CBZ was released rapidly. It is reported that AP5 and MO as the host and guest functionalized mesoporous selenium (MSe) have never been applied to agriculture. In vitro release experiments showed that the cumulative release rate of CBZ at pH 4.5 was 1.74 times higher than that in a neutral environment. In addition, we found that the contact angle of the CBZ@AP5/MSe⊃MO in maize and rape leaves was effectively decreased, which could retain more in the leaves after washout. It can also decrease the dry biomass and the reducing sugar of S.sclerotiorum. The CBZ@AP5/MSe⊃MO holds a good safety profile for plants, animal cells, and the environment owing to the targeted release properties. These results suggest that CBZ@AP5/MSe⊃MO is an environmentally friendly and effective drug-loaded system against S. sclerotiorum. It provides a new strategy for the design and development of nanopesticides and the control of S. sclerotiorum.

Complete genome sequence of peony leafroll-associated virus, a novel ampelovirus in subgroup I.

The complete genome sequence of peony leafroll-associated virus (PLRaV) was determined by deep sequencing of ribosomal-RNA-depleted total RNA extracted from a peony plant exhibiting leafroll symptoms. Further PCR and RACE analysis showed that the PLRaV genome consists of 15,406 nucleotides and contains 10 putative open reading frames, with an organization typical of members of the genus Ampelovirus, family Closteroviridae. Amino acid sequence comparisons showed that the viral heat shock protein 70 homolog (HSP70h) shared the highest sequence identity (41.7%) with the corresponding region of grapevine leafroll-associated virus 1, and the coat protein (CP) and RNA-dependent RNA polymerase (RdRp) shared the highest sequence identity (32.1% and 52.3%, respectively) with grapevine leafroll-associated virus 13. Phylogenetic analysis of the HSP70h, CP, and RdRp aa sequences showed that PLRaV clustered with members of subgroup I of the genus Ampelovirus.

Identification of a novel alphaendornavirus from Lonicera maackii.

A new alphaendornavirus, tentatively named "Lonicera maackii alphaendornavirus" (LmEV), was identified in a Lonicera maackii plant in Beijing, China, with leaf abnormality of interveinal chlorosis, and its complete genome sequence was determined using small-RNA deep sequencing. The RNA genome of LmEV is 16,176 nt in length and contains a large open reading frame encoding a polyprotein of 5363 aa with conserved domains including a cysteine-rich region, a viral helicase, and an RNA-dependent RNA polymerase. Sequence comparisons showed that LmEV shared the highest nt and aa sequence identity with Vicia faba alphaendornavirus (VfEV) of the genus Alphaendornavirus. In phylogenetic analysis of the RdRp aa sequence LmEV clustered with members of the genus Alphaendornavirus, closest to VfEV. To our knowledge, this is the first report of a novel alphaendornavirus identified in Lonicera maackii. Its effect on the host plant, if any, remains to be investigated.

Comparative Analysis of Stress and Deformation between One-Fenced and Three-Fenced Dental Implants Using Finite Element Analysis.

Finite element analysis (FEA) has always been an important tool in studying the influences of stress and deformation due to various loads on implants to the surrounding jaws. This study assessed the influence of two different types of dental implant model on stress dissipation in adjoining jaws and on the implant itself by utilizing FEA. This analysis aimed to examine the effects of increasing the number of fences along the implant and to compare the resulting stress distribution and deformation with surrounding bones. When a vertical force of 100 N was applied, the largest displacements found in the three-fenced and single-fenced models were 1.7469 and 2.5267, respectively, showing a drop of 30.8623%. The maximum stress found in the three-fenced and one-fenced models was 13.518 and 22.365 MPa, respectively, showing a drop of 39.557%. Moreover, when an oblique force at 35° was applied, a significant increase in deformation and stress was observed. However, the three-fenced model still had less stress and deformation compared with the single-fenced model. The FEA results suggested that as the number of fences increases, the stress dissipation increases, whereas deformation decreases considerably.

Metagenomic Analysis of Marigold: Mixed Infection Including Two New Viruses.

Marigold plants with symptoms of mosaic, crinkle, leaf curl and necrosis were observed and small RNA and ribo-depleted total RNA deep sequencing were conducted to identify the associated viruses. Broad bean wilt virus 2, cucumber mosaic virus, turnip mosaic virus, a new potyvirus tentatively named marigold mosaic virus (MMV) and a new partitivirus named as marigold cryptic virus (MCV) were finally identified. Complete genome sequence analysis showed MMV was 9811 nt in length, encoding a large polyprotein with highest aa sequence identity (57%) with the putative potyvirus polygonatumkingianum virus 1. Phylogenetic analysis with the definite potyviruses based on the polyprotein sequence showed MMV clustered closest to plum pox virus. The complete genome of MCV comprised of dsRNA1 (1583 bp) and dsRNA2 (1459 bp), encoding the RNA-dependent RNA polymerase (RdRp), and coat protein (CP), respectively. MCV RdRp shared the highest (75.7%) aa sequence identity with the unclassified partitivirus ambrosia cryptic virus 2, and 59.0%, 57.1%, 56.1%, 54.5% and 33.7% with the corresponding region of the definite delta-partitiviruses, pepper cryptic virus 2, beet cryptic virus 3, beet cryptic virus 2, pepper cryptic virus 1 and fig cryptic virus, respectively. Phylogenetic analysis based on the RdRp aa sequence showed MCV clustered into the delta-partitivirus group. These findings enriched our knowledge of viruses infecting marigold, but the association of the observed symptom and the identified viruses and the biological characterization of the new viruses should be further investigated.

Metabolic Disturbance and Th17/Treg Imbalance Are Associated With Progression of Gingivitis.

Objective: This study sought to explore the role of metabolic disturbance in immunoregulation of gingivitis targeting T helper 17 cells (Th17)/regulatory T cell (Treg). Materials and Methods: A total of 20 gingivitis patients and 19 healthy volunteers were recruited. Quantitative real time polymerase chain reaction (qRT-PCR) was used to evaluate expression patterns of Forkhead box protein P3 (Foxp3), transforming growth factor-ß (TGF-ß), retinoid-related orphan receptor-gammat (RORγt) and interleukin 17A (IL-17A) in the peripheral blood lymphocytes of subjects across the two groups. Moreover, the enzyme-linked immunosorbent assay (ELISA) technique was used to detect levels of TGF-ß, IL-4, IL-6,TL-10 and L-17A secreted in the plasma as well as the SIgA secreted in saliva. Flow cytometry was used to detect the percentage of CD4+CD25+ Foxp3+Treg cells and the percentage of CD4+IL-17A+ Th17 cells in whole blood of subjects in both groups. Gas chromatography-mass spectrometry (GC-MS) was employed to analyze the plasma metabolites in the gingivitis patient group. Statistical analysis was applied to determine whether the plasma metabolites and related metabolic pathways significantly differed between gingivitis patients and healthy controls. Ingenuity pathway analysis (IPA) was employed to identify the potential relation between the metabolites and the Th17 and Treg related pathway. Results: The percentages of CD4+IL17A+Th17 cells and IL-17 significantly increased in the peripheral blood in the gingivitis group. Moreover, the upregulation of IL-17A mRNA and RORγt mRNA were also found in the gingivitis group. However, the percentage of CD4+CD25+ Foxp3+Treg cells and Foxp3 mRNA in the whole blood did not significantly change. However, TGF-ß mRNA as well as TGF-ß, IL-4, IL-6, IL-10 in the periperial blood and SIgA in the saliva were higher in the gingivitis group. Notably, that the ratio of Th17/Treg cells was significantly increased during peripheral circulation. Furthermore, we identified 18 different metabolites which were differentially expressed in plasma between the gingivitis and healthy control groups. Notably, the levels of cholesterol, glycerol 1-octadecanoate, d-glucose, uric acid, cyclohexaneacetic acid, 3-pyridine, tryptophan, and undecane 2,4-dimethyl were significantly up-regulated. whereas the levels of lactic acid, glycine, linoleic acid, monopalmitic acid, glycerol, palmitic acid, pyruvate, 1-(3-methylbutyl)-2,3,4,6-tetramethylbenzene, 1 5-anhydro d-altrol, and boric acid were down-regulated in the gingivitis group, relative to healthy controls. IPA showed that these metabolites are connected to IL17 signaling, TGF-B signaling, and IL10 signaling, which are related closely to Th17 and Treg pathway. Conclusion: Overall, these results showed that disturbance to glycolysis as well as amino and fatty acid metabolism are associated with Th17/Treg balance in gingivitis. Impaired immunometabolism may influence some periodontally involved systemic diseases, hence it is a promising strategy in targeted development of treatment therapies.

First Report of broad bean wilt virus-2 in marigold (Tagetes erecta L.) in China.

Broad bean wilt virus 2 (BBWV-2), a member of the genus Fabavirus in the family Secoviridae mainly transmitted by aphids, has been recognized as a severe pathogen affecting the production of horticultural and ornamental plants worldwide (Xia et al. 2020). The virus was reported to infect many plant species mostly belonging to the family Fabaceae in China (Wang et al. 2017). In August 2018, marigold plants with the symptom of mosaic were observed in the field of Huairou, Beijing (Figure S1). Total RNA was extracted from symptomatic leaf samples from a single plant with TRIzol reagent (Invitrogen, Carlsbad, CA) with a standard procedure following the manufacturer's instructions, and small RNAs were isolated for deep sequencing library construction with Illumina TruSeq Small RNA Sample Prep Kit (Illumina, San Diego, CA, USA). The high-throughput sequencing was carried out on an Illumina HiSeq2500 platform. After raw data process, 8,911,917 clean reads were gained and further de novo assembled into contigs with CLC Genomics Workbench software. BLASTN and BLASTX analysis against the GenBank database showed that 81 of the 9,495 assembled contigs shared high nucleotide (nt) sequence identity with the bipartite genome of BBWV-2 isolate Gyp (KX686589-KX686590 for RNA1 and RNA2, 89% of the genome coverage and 90% nt identity) and 34 with high nt sequence identity of cucumber mosaic virus(CMV) from Tagetes erecta (EU665000-EU665002 for RNA1-RNA3,89% of the genome coverage and 96% nt sequence identity) with sequence coverage ranging from 24-fold to 8,078-fold at different genome positions. To further confirm the presence of BBWV-2, a RNA2 specific primer pair targeting the coat protein region (F1423-1448,5-CTGACAGAGGAATACTATTTCCAAAG-3;R2692-2719,5-CCTGTAAAATTGATATCTCCGGACAAAC-3) was designed from the obtained HTS sequence and reverse transcription-polymerase chain reaction (RT-PCR) was conducted. The 1.3 kb amplicon was ligated to pMD19-T vector (TaKaRa, Dalian, China) and sequenced. Sequence analysis showed it (BBWV-2-marigold, MW322809) shared 99% nt sequence identity with the Gyp isolate infecting Gynura procumbens from South Korea (LC497425.1). Phylogenetic analysis constructed with MEGA6 with the CP nt sequence of other reported BBWV-2 isolates showed BBWV-2-marigold clustered closely with the isolates from South Korea infecting Gynura procumbens (Figure S2), in accordance with the sequence identity analysis. Further RT-PCR with primer pair targeting the RNA1 (F3025-3050 5-GACAGAGTGATATTCCTAATCGAGAT-3; R4035-4062CACTCAATGC AATAAAGGTCTGGCACCT) was conducted and specific bands with the expected size of 1.0 kb were obtained in the agarose gel (data not shown), which further confirmed the existence of BBWV-2.A total of 16 marigold leaf samples(7 from Huairou and 9 from Yanqing) with mosaic symptom were collected and tested by RT-PCR with the abovementioned primer pair, and 4 from Huairou were BBWV-2 positive. Sequence analysis showed that these 4 isolates shared 100% nt sequence identity with the former sequenced isolateBBWV-2-marigold. Furthermore, CMV specific primer pair targeting the CP (F: 5-ATGGACAAATCTGGATCTCCCAAT-3/R: 5-CTAAGTCGGG AGCATCCGTGAGAT-3) were designed to detect the existence of CMV in these samples and results showed that all these 16 samples were positive for CMV. To the best of our knowledge, this is the first report of BBWV-2 in marigold in China.These findings will assist investigations on the epidemiology of diseases caused by BBWV2 in China.

Characterization of Corneal Biomechanical Properties and Determination of Natural Intraocular Pressure Using CID-GAT.

PURPOSE: The intraocular pressure (IOP) measured using Goldmann Applanation Tonometry (GAT) is confounded by individual corneal properties. We investigated a modified method that removes the confoundment by incorporating corneal properties into the Imbert-Fick's law is investigated. METHOD: Porcine eyes were pressurized between 10 and 40 mm Hg using a manometer. The eyes were indented using a flat cylindrical indenter. A modified corneal indentation device (CID) procedure was used to obtain the corneal moduli Eqs . The calculated IOPNC from the Imbert-Fick's Law using the corneal moduli Eqs was compared to the natural IOPN, measured using pressure sensor inserted into the eye. RESULTS: Test results showed that IOP-dependent corneal modulus Eqs is a primary confounding factor in IOP calculation. The average elastic modulus Eqs is 0.173 ± 0.018 MPa at 20 mm Hg, and increases with IOP at a linear rate of 0.0066 MPa per mm Hg (r = 0.997, P < 0.001). Incorporation of individual Eqs into IOPNC calculation showed that IOPNC are in good agreement with reference IOPN (slope = 0.999, r = 0.939, P < 0.001). CONCLUSIONS: The IOP-dependent corneal modulus Eqs is a primary confounding factor in IOP calculation. A modified CID-GAT procedure to obtain natural cornea-independent IOPNC is developed and verified in this study. The CID-GAT IOP modification may be used in place of conventional GAT when the confounding effects in eyes with atypical cornea (e.g., laser-assisted in situ keratomileusis [LASIK] thinned) are significant. TRANSLATIONAL RELEVANCE: Confoundment from corneal properties results in IOP measurement errors. The study showed that the CID-GAT method can significantly reduce the confounding corneal errors.

In vivo measurement of regional corneal tangent modulus.

Currently available clinical devices are unable to measure corneal biomechanics other than at the central region. Corneal stiffness (S), thickness, and radius of curvature was measured at the central cornea (primary fixation) and 3 mm from the temporal limbus (primary and nasal fixations). The corneal tangent modulus (E) of 25 healthy subjects was calculated from these data. After confirming normality, repeated measures analysis of variance (RMANOVA) revealed significant difference in S (F(2, 48) = 21.36, p < 0.001) at different corneal regions and direction of fixations. E also varied significantly at different corneal regions and direction of fixations (RMANOVA: F(2, 48) = 23.06, p < 0.001). A higher S and a lower E were observed at the temporal region compared with the corneal centre. Nasal fixation further increased S and E values compared with primary fixation. Due to the specific arrangement of corneal collagen fibrils, heterogeneity of corneal biomechanical properties is expected. In future clinical practice, localized corneal biomechanical alternation and measurement might assist corneal disease detection and post-surgery management. In addition, practitioners should be aware of the fixation effect on corneal biomechanical measurement.

High myopes have lower normalised corneal tangent moduli (less 'stiff' corneas) than low myopes.

PURPOSE: To compare corneal tangent moduli between low and high myopes. METHODS: Corneal hysteresis (CH) and corneal resistance factor (CRF) of 32 low and 32 high myopes were obtained using an Ocular Response Analyzer, followed by a corneal indentation device that measured corneal stiffness. Corneal topography, pachymetry, Goldmann applanation tonometry intraocular pressure (GAT-IOP), and corneal compensated intraocular pressure (IOPcc) were also obtained. Corneal tangent modulus was calculated on the basis of corneal stiffness, central corneal thickness and corneal radius. Comparisons between groups and associations between corneal biomechanical and ocular parameters were performed. RESULTS: Corneal tangent moduli were positively correlated with GAT-IOP (R2 = 0.078, p = 0.025), and IOPcc (R2 = 0.12, p = 0.006). Despite similarity in corneal thickness and radius, high myopes exhibited a significantly higher IOPcc (16.4 ± 2.51 mmHg) than low myopes (13.1 ± 1.96 mmHg; t(62) = -5.57, p < 0.0001). Both groups had similar corneal stiffness (0.063 ± 0.0085 and 0.063 ± 0.0079 N mm-1 for low and high myopes, respectively) and CRF (9.6 ± 1.58 and 9.5 ± 1.90 mmHg for low and high myopes, respectively). Moreover, high myopes exhibited a significantly lower CH (9.5 ± 1.51 mmHg) than low myopes (10.6 ± 1.38 mmHg; t(62) = 2.92, p = 0.005). After normalising corneal tangent moduli to the mean intraocular pressure in normal eyes (15.5 mmHg) using IOPcc, high myopes showed a significantly lower corneal tangent moduli (0.47 ± 0.087 MPa) than low myopes (0.57 ± 0.099 MPa; t(62) = 4.17, p < 0.0001). CONCLUSIONS: High myopes had lower normalised corneal tangent moduli than low myopes, which indicated that their corneas were less stiff. This is the first in vivo study comparing elastic moduli of the cornea in different refractive groups. Further studies are warranted to understand whether a less stiff cornea is a cause for or an outcome from myopia development.

Diurnal Variation of Corneal Tangent Modulus in Normal Chinese.

PURPOSE: The aim of this study was to investigate the diurnal variation of corneal tangent modulus, measured using a novel corneal indentation device, in healthy Chinese subjects. METHODS: The central corneal thickness (CCT), mean central corneal radius (meanK), intraocular pressure (IOP), and corneal stiffness of 25 young adults aged 21 to 25 years (23.0 ± 1.0 yrs) were measured at 3-hour intervals from 09:00 to 21:00 in the course of 1 day. Corneal tangent modulus was calculated on the basis of corneal stiffness, CCT, and meanK. Repeated-measures analyses of variance were performed to compare the diurnal changes in ocular parameters over time. RESULTS: Significant diurnal variations were observed in CCT and IOP (P < 0.001 and P = 0.025, respectively). Both parameters showed a decreasing trend throughout the day. MeanK and corneal stiffness did not show any significant diurnal changes (P = 0.251 and P = 0.516, respectively). Mean corneal tangent modulus across all measurements was 0.047 ± 0.085 MPa, and its diurnal rhythm ranged from 0.469 to 0.485 MPa. The variation was nonsignificant (P = 0.526). CONCLUSIONS: The elastic properties of the cornea in healthy Chinese subjects were stable during wake time. The present study shows that the corneal indentation device obtains stable corneal biomechanics similar to other clinical devices. Future studies investigating the differences in corneal biomechanics among patients with various ocular conditions are warranted.