Comparative complete chloroplast genome of Geum japonicum: evolution and phylogenetic analysis.

Geum japonicum (Rosaceae) has been widely used in China as a traditional herbal medicine due to its high economic and medicinal value. However, the appearance of Geum species is relatively similar, making identification difficult by conventional phenotypic methods, and the studies of genomics and species evolution are lacking. To better distinguish the medicinal varieties and fill this gap, we carried out relevant research on the chloroplast genome of G. japonicum. Results show a typical quadripartite structure of the chloroplast genome of G. japonicum with a length of 156,042 bp. There are totally 131 unique genes in the genome, including 87 protein-coding genes, 36 tRNA genes, and 8 rRNA genes, and there were also 87 SSRs identified and mostly mononucleotide Adenine-Thymine. We next compared the plastid genomes among four Geum species and obtained 14 hypervariable regions, including ndhF, psbE, trnG-UCC, ccsA, trnQ-UUG, rps16, psbK, trnL-UAA, ycf1, ndhD, atpA, petN, rps14, and trnK-UUU. Phylogenetic analysis revealed that G. japonicum is most closely related to Geum aleppicum, and possibly has some evolutionary relatedness with an ancient relic plant Taihangia rupestris. This research enriched the genome resources and provided fundamental insights for evolutionary studies and the phylogeny of Geum.

[Correlation between ecological factors and effective component content, flower, and leaf traits of Epimedium pubescens].

No systematic research has been reported on the correlation between different ecological factors and the effective component content, flower, and leaf traits of Epimedium pubescens. In this study, 21 kinds of E. pubescens in different regions were investigated, and the content of two effective components of icariin(I) and Epimedin C(C), as well as six leaf traits and 12 flower traits were determined. The correlation between 11 ecological factors and the above traits in different regions for five consecutive years was explored. The results showed that no significant correlation was observed between the ecological factors and the total content of two effective components(I+C) of E. pubescens. Latitude and temperature(including annual average temperature, annual average minimum temperature, and soil temperature of each soil layer) were significantly positively and negatively correlated with the ratio of the content of the two effective components(C/I)(P<0.01), respectively. There was a significant correlation between ecological factors and flower traits, and the annual average soil temperature of each soil layer, annual average temperature, and annual average minimum temperature were significantly correlated with most flower traits in multiple years(P<0.01). However, a weak correlation between ecological factors and leaf traits was detected. A significant positive correlation of the annual average soil temperature of each soil layer and annual average humidity(P<0.01) with the width of nutrient leaf in only a few years was detected. Therefore, it was concluded that the total content of effective components of E. pubescens was determined by genetics, with a slight influence of ecological factors. The annual average temperature, annual average minimum temperature, and soil temperature of each soil layer were the ecological factors that had the most significant impact on flower traits, which showed significant differences in different regions, and similar results were not found in leaf traits. Overall, this study systematically conducted a correlation analysis between ecological factors and the effective components, as well as flower and leaf traits, providing guidance for the quality improvement, introduction, and domestication of E. pubescens.

Epicardial adipose tissue in patients with chronic obstructive pulmonary disease: systematic review with meta­analysis and trial sequential analysis.

BACKGROUND: Limited data suggest that chronic obstructive pulmonary disease (COPD) patients have pathologic elevated epicardial adipose tissue (EAT), which is splanchnic fat tissue with anti-inflammatory properties and regulating free fatty acids functions. Therefore, there is a need for meta-analysis to explore the relationship between EAT and COPD. METHODS: Online databases were systematically searched for studies about EAT in COPD patients published up to October 5th, 2022. The EAT data of the COPD patient group and the control group were included. Trial sequential analysis (TSA) and meta-analysis were applied to assess the difference in EAT between patients with and without COPD. TSA software and Stata 12.0 were used in all statistical analyses. RESULTS: The final analysis included 5 studies (n = 596 patients). COPD patients had significantly more EAT than control subjects (SMD: 0.0.802; 95% CI: 0.231, 1.372; P = 0.006; TSA-adjusted 95% CI 1.20, 1.80; P < 0.0001). And higher CRP levels in COPD patients than non-COPD patients, whereas triglycerides and LDL were not significantly different between patients with and without COPD. CONCLUSION: EAT is abnormally elevated in COPD patients, which may be related to systemic inflammatory responses in COPD. PROSPERO NUMBER: CRD42021228273.

Complete chloroplast genome of Gentianopsis barbata and comparative analysis with related species from Gentianaceae.

Gentianopsis barbata is an essential medicinal plant in China with high ornamental and medicinal values. Unfortunately, the study of the chloroplast genome of this plant still has a gap. This study sequenced and characterized the complete chloroplast genome of G. barbata. The complete chloroplast genome of G. barbata is a typical circular structure of 151 123 bp. It consists of a large single-copy region (82 690 bp) and a small single-copy region (17 887 bp) separated by a pair of inverted repeats (25 273 bp), which covers 78 protein-coding genes, 30 tRNAs, and 4 rRNAs. The long repeat sequence analysis showed that the P-type (palindromic) sequences were the major long repeat sequences. Thirty-seven simple sequence repeats were identified, most of which were single nucleotides. The Bayesian inference tree, maximum likelihood tree, and neighbor-joining tree suggested that G. barbata is grouped with Gentianopsis grandis and Gentianopsis paludosa. The divergence time analysis showed that G. barbata diverged at 1.243 Mya. Comparative analysis of chloroplast genomes can reveal interspecific diversity, and regions with high variation can be used to develop molecular markers applicable to various research areas. Our results provide a new insight into plastome evolution and a valuable resource for further studies on G. barbata.

Screening of the Hepatotoxic Components in Fructus Gardeniae and Their Effects on Rat Liver BRL-3A Cells.

Fructus Gardeniae (FG) is a common Chinese medicine and food. However, the toxicity of FG has drawn increasing concern, especially its hepatotoxicity. The purpose of this study was to screen the hepatotoxic components of FG and evaluate their effects on rat liver BRL-3A cells. The chemical composition of FG was determined by HPLC-ESI-MS. CCK-8 assay was used to evaluate the cytotoxicity of ten chemical components from FG, and then the toxic components with significant inhibitory activity were selected for further study. The results showed that geniposide, genipin, genipin-1-gentiobioside, gardenoside, and shanzhiside all suppress cells viability. Apoptosis assays further indicated that geniposide and its metabolite genipin are the main hepatotoxic components of FG. Pretreatment of cells with geniposide or genipin increased the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP). The activities of superoxide dismutase (SOD) and glutathione (GSH) were decreased, while the malondialdehyde (MDA) level was increased. The cell contents of tumor necrosis factor (TNF-α), interleukin-6 (IL-6), and nitric oxide (NO) were also increased. Molecular docking simulations were used to investigate the mechanism of FG-induced hepatotoxicity, revealing that geniposide and genipin bind strongly to the pro-inflammatory factor TNFR1 receptor of the NF-κB and MAPK signaling pathways. The obtained results strongly indicate that the hepatotoxicity of FG is caused by iridoids compounds. Genipin had the most significant hepatotoxic effect. These toxic substances destroy the cell antioxidant defense system, increasing inflammatory injury to the liver cells and leading to apoptosis and even necrosis. Thus, this study lays a foundation for toxicology research into FG and its rational application.

Study of the osteogenesis effect of icariside II and icaritin on canine bone marrow mesenchymal stem cells.

This study aimed to identify the osteogenesis effect of icariside II (ICSII) and icaritin (ICT) in vitro. Bone marrow mesenchymal stem cells (BMSCs) were treated with ICSII and ICT in order to detect the proliferation and differentiation of BMSCs, the expression of the osteogenesis-related proteins with or without osteogenic medium (OM) and genes, Runt-related transcription factor 2 (Runx-2), osteocalcin (OCN), osteopontin (OPN), osterix, and basic fibroblast growth factor (bFGF), and the phosphorylation levels of mitogen-activated protein kinase (MAPK). We found that the optical density increased and alkaline phosphatase decreased after the BMSCs were treated with different concentrations of ICSII; however, ICT showed an opposing effect. The formation of calcium nodules was observed after the BMSCs were treated with ICSII and ICT. The expression level of osteogenesis-related proteins was enhanced following treatment with both ICSII or ICT, while the expression level of the osteogenesis-related genes Runx-2, OCN, OPN, osterix, and bFGF significantly increased with ICSII treatment (P < 0.05), and only Runx-2 and bFGF significantly increased (P < 0.01) with ICT. The expression of osteogenic differentiation-related proteins (except OPN) following treatment with ICSII + OM or ICT + OM was not notably increased. Both ICSII and ICT elevated the phosphorylation levels of MAPK/ERK, which was attenuated by GDC-0994 (an inhibitor of MAPK/ERK). Collectively, these data indicate that ICSII and ICT facilitate orientation osteogenic differentiation of BMSCs, which is most likely via the MAPK/ERK pathway. OM did not synergistically enhance the osteogenesis effect of ICSII and ICT.

[Research on XOD captured components in Lagotis brevituba based on UPLC-Q-TOF-MS and molecular docking technology].

Potential xanthine oxidase (XOD) inhibitors in Lagotis brevituba were captured by using affinity and ultrafiltration. The structures of the captured components were identified by ultra-performance liquid chromatography coupled with Q-TOF mass spectrometry (UPLC-Q-TOF-MS). The binding intensity and binding mechanism between the captured components and XOD were analyzed by using molecular docking software Autodock 4.2. A total of 17 compounds were identified, including 9 flavonoids, 5 phenolic acids and 3 triterpenes. Molecular docking results showed that all the captured components could be spontaneously bound with XOD mainly via hydrogen bond, Van der Waals' force and hydrophobic interaction. From the perspective of binding energy and scoring function, the collected fractions all had potential prospects for XOD inhibitors, and the flavonoid luteolin-3',7 glucuronide had the best effect. The results also showed that affinity and ultrafiltration, ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) and molecular docking technology can provide a powerful tool for the analysis of XOD inhibitor components in natural products.

Synthesis and Evaluation of 5-(o-Tolyl)-1H-tetrazole Derivatives as Potent Anticonvulsant Agents.

A series of 5-(o-tolyl)-1H-tetrazole derivatives were synthesized and evaluated for their anticonvulsant activities. 1-(2-Methylbenzyl)-5-(o-tolyl)-1H-tetrazole (3h) showed important anticonvulsant activity against the MES-induced seizures, as well as lower neurotoxicity with an ED50 value of 12.7 mg/kg and a TD50 value of over 500 mg/kg after intraperitoneal injection into mice, providing 3h with a high protective index (TD50 /ED50 ) of over 39.4. The achieved results prove that the distinctive compounds could be valuable as a model for future development, adaptation, and investigation to construct more active analogues.

[Study on commercial specification of Gardenia jasminoides].

Collecting different commodity grade Gardenia jasminoides of wild and cultivated varieties all over the country, obtaining color information from each batch of G. jasminoides by the standard D65 light source and image acquisition system, quantifing the gardenia plumpness information by the digital display vernier caliper, determinating 6 kinds of effective components of G. jasminoides by HPLC, classifing from ten indicators by two step clustering analysis and correspondence analysis method of statistics, clearing the importance of the traditional identification indexes, establishing multiple corresponding relation between the skin color and commercial specification of G. jasminoides,exploring the correlation of the skin color and chemical composition, to provide the reference for the reasonable division of commercial specifications and grades of G. jasminoides. Medicine is divided into two classes and has obvious distinguish meaning, The importance of the skin color is greater than the plumpness in traditional identification characteristics, it can accurately distinguish the specifications of G. jasminoides. We improve and rebuild the standard of commodity specifications and grades of Gardenia jasminoides Ellis and establish the rapid evaluation method by the study, it provide a new way and idea for the comprehensive evaluation of G. jasminoides quality.

[Fast identification of constituents of Lagotis brevituba by using UPLC-Q-TOF-MS/MS method].

The chemical constituents of Lagotis brevituba were rapidly determined and analyzed by using ultra performance liquid chromatography tandem quadrupole time of flight mass spectrometry (UPLC-Q-TOF-MS/MS) method, providing material basis for the clinical application of L. brevituba. The separation was performed on UPLC YMC-Triart C18 (2.1 mm×100 mm, 1.9 µm) column, with acetonitrile-water containing 0.2% formic acid as mobile phase for gradient elution. The flow rate was 0.4 mL•min-1 gradient elution and column temperature was 40 ℃, the injection volume was 2 µL. ESI ion source was used to ensure the data collected in a negative ion mode. The chemical components of L. brevituba were identified through retention time, exact relative molecular mass, cleavage fragments of MS/MS and reported data. The results showed that a total of 22 compounds were identified, including 11 flavones, 6 phenylethanoid glycosides, 1 iridoid glucosides, and 4 organic acid. The UPLC-Q-TOF-MS/MS method could fast identify the chemical components of L. brevituba, providing valuable information about L. brevituba for its clinical application.

[Comparison of chemical constituents in different parts of Gardenia jasminoides based on multiple wavelength HPLC-DAD].

Seven compounds(deacetylasperulasidic acid methyl ester, gardenoside, chlorogenic acid, geniposide, crocin-Ⅰ, crocin-Ⅱ, chikusetsu saponin Ⅳa)were determined simultaneously by multiple wavelength HPLC with diode array detector(DAD) in different parts of Gardenia jasminoides. The results showed that these components in different parts of G. jasminoides had a different distribution, and there was a large difference in content of each component. Geniposide was mainly distributed in fruits and leaves; chikusetsu saponin Ⅳa was mainly distributed in roots and stems; crocus glycosides existed mainly in fruits; chlorogenic acid had a higher distribution in leaves and stems; gardenoside had a higher distribution in leaves and roots, while ceacetylasperulasidic acid methyl ester had a higher distribution in roots and stems. Based on the analysis of the chemical composition and content difference in different parts of G. jasminoides, the basis for the comprehensive utilization and quality evaluation of resources of G. jasminoides was provided.

[Comparative Study on Protection Effects of CCl4-Induced Acute Liver Injury of Different Prepared Products from Gardenia jasminoides Fruits in Rats].

Objective: To provide the experimental evidence for the appropriate selection of the different prepared products from Gardenia jasminoides fruits by comparing their protection effects on carbon tetrachloride（ CCl4）-induced acute liver injury. Methods: The activities of ALT,AST,ADA,LDH,ALP and contents of PA,TP,TBIL,DBIL,TBA in serum,the activities of SOD and the content of MDA in liver tissue were measured in acute liver injury rats by carbon tetrachloride. Also the pathological changes of liver tissues were examined under microscope. Results: The biochemical indexes of AST,ALT,TBA,ADA,LDH and MDA were significantly improved in all groups of prepared products from Gardenia jasminoides fruits,but not SOD and ALP. The lesions of liver tissue had different degrees of reduction. Conclusion: The different prepared products from Gardenia jasminoides fruits had the effects of liver protection. The nut of Gardeniae Fructus was superior to the peel in enzyme decreasing and liver protection. The crude was superior to the stir-cooked in enzyme decreasing and liver protection.

[Study on ecological suitability of Gardenia jasminoides based on ArcGIS and Maxent model].

The application of ArcGIS and Maxent modelto analyze the ecological suitability of Gardenia jasminoides.Taking 85 batches of Gardenia as the basis of analysis, the selection of ecological factors for the growth of Gardenia. The results showed that the average precipitation in April, the average precipitation in November and the average precipitation in August were the most important factors affecting the growth of Gardenia. The relative concentration of Gardenia suitable growth region,north to the south of Shaanxi province, south of Henan, central Anhui, south to the north of Hainan province, west to central Sichuan province, east of Zhejiang coastal area, northeast of Taiwan.

Cdc5-dependent asymmetric localization of bfa1 fine-tunes timely mitotic exit.

In budding yeast, the major regulator of the mitotic exit network (MEN) is Tem1, a GTPase, which is inhibited by the GTPase-activating protein (GAP), Bfa1/Bub2. Asymmetric Bfa1 localization to the bud-directed spindle pole body (SPB) during metaphase also controls mitotic exit, but the molecular mechanism and function of this localization are not well understood, particularly in unperturbed cells. We identified four novel Cdc5 target residues within the Bfa1 C-terminus: (452)S, (453)S, (454)S, and (559)S. A Bfa1 mutant in which all of these residues had been changed to alanine (Bfa1(4A)) persisted on both SPBs at anaphase and was hypo-phosphorylated, despite retaining its GAP activity for Tem1. A Bfa1 phospho-mimetic mutant in which all of these residues were switched to aspartate (Bfa1(4D)) always localized asymmetrically to the SPB. These observations demonstrate that asymmetric localization of Bfa1 is tightly linked to its Cdc5-dependent phosphorylation, but not to its GAP activity. Consistent with this, in kinase-defective cdc5-2 cells Bfa1 was not phosphorylated and localized to both SPBs, whereas Bfa1(4D) was asymmetrically localized. BFA1(4A) cells progressed through anaphase normally but displayed delayed mitotic exit in unperturbed cell cycles, while BFA1(4D) cells underwent mitotic exit with the same kinetics as wild-type cells. We suggest that Cdc5 induces the asymmetric distribution of Bfa1 to the bud-directed SPB independently of Bfa1 GAP activity at anaphase and that Bfa1 asymmetry fine-tunes the timing of MEN activation in unperturbed cell cycles.

[Study on chemical constituents of Gardenia jasminoides(III)].

OBJECTIVE: To investigate the chemical constituents of Gardenia jasminoides fruits. METHODS: Various column chromatography were used in the isolation and purification, and physiochemical constant determination and spectral analysis were adopted to determine the chemical structures. RESULTS: Twelve compounds were isolated from Gardenia jasminoides including jasminoside I (1), gardenoside (2), gardaloside (3), 3-hydroxy-urs-12-ene-11-ketone(4), 5, 4'-dihydroxyl-7, 3', 5'-trimethoxyflavone (5), 5, 7, 3', 4', 5'-pentamethoxyflavone(6), 3, 5, 6, 4'-tetrahydroxy-3', 5'-dimethoxyflavone (7), shikimic acid (8), 1, 2, 4-benzenetriol (9), 3, 4-dimethoxy-benzoic acid (10), dibutyl phthalate (11) and diisobutyl phthalate (12). CONCLUSION: Compounds 4 - 7 and 9 -10 were isolated from this plant for the first time.

A comparative study of progressive failure of granite and marble rock bridges under direct shearing.

Shear failure of rock bridges is an important process in geological phenomena, including landslides and earthquakes. However, the progressive failure of natural rock bridges has not yet been fully understood. In this work, we carried out direct shearing experiments on both granite and marble rock bridges, and applied acoustic emission (AE) monitoring throughout the experiments. With the mechanical curves and the evolution of AE activity (including AE energy rate and b value), the failure of rock bridges can be divided into three pre-failure phases and one ultimate failure phases. We analyzed the effects of normal stress and lithology on the pre-failure phases. We noted that with the increasing of normal stress, the length of stable cracking phase decreases and the length of unstable cracking phase slightly increases, except for marble rock bridges at high normal stress, which maintains a great proportion of stable cracking phase that possibly results from the great off-fault damage. Increasing normal stress also suppresses the dilation of granite rock bridges, but has a different effect on marble rock bridges, which also suggests the effect of lithology on failure modes.

Molecular mechanism of geniposide against ANIT-induced intrahepatic cholestasis by integrative analysis of transcriptomics and metabolomics.

Geniposide (GE), a bioactive compound extracted from the fruit of Gardenia jasminoides Ellis, has attracted significant attention for its hepatoprotective therapeutic applications. Although GE displays a protective effect on treating intrahepatic cholestasis (IC), the underlying mechanism remains elusive. In this study, we aimed to elucidate the pharmacological mechanisms of GE in treating IC by an integrated analysis of transcriptomics and metabolomics. Firstly, we evaluated the hepatoprotective effect of GE in α-naphthylisothiocyanate (ANIT)-induced IC rats by examining biochemical indices, inflammatory factors, and oxidative stress levels. Secondly, by transcriptomics and serum metabolomics, we identified differentially expressed genes and metabolites, revealing phenotype-related metabolic pathways and gene functions. Lastly, we screened the core targets of GE in the treatment of IC by integrating transcriptomic and metabolomic data and validated these targets using western blotting. The results indicated that GE improved serum indexes and alleviated inflammation reactions and oxidative stress in the liver. The transcriptomics analysis revealed 739 differentially expressed genes after GE treatment, mainly enriched in retinol metabolism, steroid hormone synthesis, PPAR signal transduction, bile secretion metabolism, and other pathways. The metabolomics analysis identified 98 differential metabolites and 10 metabolic pathways. By constructing a "genes-targets-pathways-compounds" network, we identified two pathways: the bile secretion pathway and the glutathione pathway. Within these pathways, we discovered nine crucial targets that were subsequently validated through western blotting. The results revealed that the GE group significantly increased the expression of ABCG5, NCEH1, OAT3, and GST, compared with the ANIT group. We speculate that GE has a therapeutic effect on IC by modulating the bile secretion pathway and the glutathione pathway and regulating the expression of ABCG5, NCEH1, OAT3, and GST.

Characterization of microbial community assembly in parasitic plant systems and the influence of microorganisms on metabolite accumulation in parasitic plants: case study of Cistanche salsa and Kalidium foliatum.

Introduction: Cistanche salsa (C.A.Mey.) G. Beck is a perennial holoparasitic herb recognized for its medicinal properties, particularly in kidney-tonifying and laxative treatments. Despite its therapeutic potential, little is known about the endophyte communities inhabiting C. salsa and its host plants, and how these microorganisms may impact the production and accumulation of metabolites in C. salsa. Methods: We conducted a dual analysis focusing on metabolomics of wild C. salsa and microbiome characterization of both C. salsa and its host plant, Kalidium foliatum (Pall.) Moq. The metabolomics analysis revealed variations in metabolite composition across different parts of C. salsa. Additionally, the microbiome analysis involved studying endophytic bacteria and fungi, comparing their community structures between parasitic C. salsa and its host plant. Results: Significant variations in metabolite composition were observed through metabolomic profiling, which identified 93 secondary metabolites and 398 primary metabolites across various parts of C. salsa. Emphasis was placed on differences in metabolite composition within the flowers. Microbiome analysis revealed differential community compositions of endophytic bacteria between the parasitic and host plants, whereas differences in endophytic fungi were less pronounced. Certain endophytes, such as Bacteroidota, Proteobacteria, Ascomycota, and Basidiomycota, were associated with the production of specific secondary metabolites in C. salsa, including the plant-specific compound salsaside. Discussion: Our findings highlight the intricate relationship between C. salsa and its endophytic microbiota, suggesting a potential role of these microorganisms in modulating the biosynthesis of bioactive compounds. The differential preferences of endophytic bacteria and fungi across various microenvironments within the parasitic plant system underscore the complexity of these interactions. Further elucidation of these dynamics could enhance our understanding of C. salsa's medicinal properties and its ecological adaptations as a holoparasitic herb.

Two-stage extraction by partial grinding of impacted mandibular third molar in close proximity to the inferior alveolar nerve.

BACKGROUND: Extraction of impacted third molars often leads to severe complications caused by damage to the inferior alveolar nerve (IAN). AIM: To proposes a method for the partial grinding of an impacted mandibular third molar (IMM3) near the IAN to prevent IAN injury during IMM3 extraction. METHODS: Between January 1996 and March 2022, 25 patients with IMM3 roots near the IAN were enrolled. The first stage of the operation consisted of grinding a major part of the IMM3 crown with a high-speed turbine dental drill to achieve sufficient space between the mandibular second molar and IMM3. After 6 months, when the root tips were observed to be away from the IAN on X-ray examination, the remaining part of the IMM3 was completely removed. RESULTS: All IMM3s were extracted easily without symptoms of IAN injury after extraction. CONCLUSION: Partial IMM3 grinding may be a good alternative treatment option to avoid IAN injury in high-risk cases.

Transcutaneous oxygen pressure measurement in diabetic foot ulcers: mean values and cut-point for wound healing.

PURPOSE: The purpose of this study was to investigate mean values and cut-point of transcutaneous oxygen pressure (TcPO2) measurement in patients with diabetic foot ulcers. DESIGN: Prospective, descriptive study. SUBJECTS AND SETTING: Sixty-one patients with diabetes mellitus and foot ulcers comprised the sample. The research setting was Sun Yat-sen Memorial Hospital of SunYat-sen University, Guangzhou, China. METHODS: Participants underwent transcutaneous oxygen (TcPO2) measurement at the dorsum of foot. Patients were classified into 3 groups according to clinical outcomes: (1) ulcers healed with intact skin group, (2) ulcer improved, and (3) ulcer failed to improve. TcPO2 was assessed and cut-points for predicting diabetic foot ulcer healing were calculated. RESULTS: Thirty-six patients healed with intact skin, 8 experienced improvement, and 17 showed no improvement. Mean TcPO2 levels were significantly higher (P< .001) in healed ulcers with intact skin (32 ± 10 mmHg) when compared to the improvement group (30 ± 7 mmHg) and the nonhealing group (15 ± 12 mmHg). All patients with TcPO2≤ 10 mmHg failed to heal or experienced deterioration in their foot ulcers. In contrast, all patients with TcPO2≥ 40 mmHg achieved wound closure. Measurement of TcPO2 in the supine position revealed a cut-point value of 25 mmHg as the best threshold for predicting diabetic foot ulcer healing; the area under the curve using this cut-point was 0.838 (95% confidence interval = 0.700-0.976). The sensitivity, specificity, positive predictive value, and negative predictive value for TxPO2 were 88.6%, 82.4%, 90.7%, and 72.2%, respectively. CONCLUSION: TcPO2≥ 40 mmHg was associated with diabetic foot ulcer healing, but a TcPO2≤ 10 mmHg was associated with failure of wound healing. We found that a cut-point of 25 mmHg was most predictive of diabetic foot ulcer healing.