Genome Assembly of Cordia subcordata, a Coastal Protection Species in Tropical Coral Islands.

Cordia subcordata trees or shrubs, belonging to the Boraginaceae family, have strong resistance and have adapted to their habitat on a tropical coral island in China, but the lack of genome information regarding its genetic background is unclear. In this study, the genome was assembled using both short/long whole genome sequencing reads and Hi-C reads. The assembled genome was 475.3 Mb, with 468.7 Mb (99.22%) of the sequences assembled into 16 chromosomes. Repeat sequences accounted for 54.41% of the assembled genome. A total of 26,615 genes were predicted, and 25,730 genes were functionally annotated using different annotation databases. Based on its genome and the other 17 species, phylogenetic analysis using 336 single-copy genes obtained from ortholog analysis showed that C. subcordata was a sister to Coffea eugenioides, and the divergence time was estimated to be 77 MYA between the two species. Gene family evolution analysis indicated that the significantly expanded gene families were functionally related to chemical defenses against diseases. These results can provide a reference to a deeper understanding of the genetic background of C. subcordata and can be helpful in exploring its adaptation mechanism on tropical coral islands in the future.

miR-1249-5p regulates the osteogenic differentiation of ADSCs by targeting PDX1.

BACKGROUND: Osteoporosis (OP) is an age-related systemic bone disease. MicroRNAs (miRNAs) are involved in the regulation of osteogenic differentiation. The purpose of this study was to explore the role and mechanism of miR-1249-5p for promoting osteogenic differentiation of adipose-derived stem cells (ADSCs). METHODS: GSE74209 dataset was retrieved from NCBI Gene Expression Omnibus (GEO) database and performed bioinformatic analyses. OP tissue and healthy control tissues were obtained and used for RT-PCR analyses. ADSCs were incubated with miR-1249-5p mimic, inhibitor and corresponding negative control (NC), alkaline phosphatase (ALP) staining, and Alizarin Red Staining (ARS) were then performed to assess the role of miR-1249-5p for osteogenesis of ADSCs. Targetscan online website and dual-luciferase reporter assay were performed to verify that the 3'-UTR of PDX1 mRNA is a direct target of miR-1249-5p. RT-PCR and western blot were also performed to identify the mechanism of miR-1249-5p for osteogenesis of ADSCs. RESULTS: A total of 170 differentially expressed miRNAs were selected, among which, 75 miRNAs were downregulated and 95 miRNAs were upregulated. Moreover, miR-1249-5p was decreased in OP patients, while showed a gradual increase with the extension of induction time. miR-1249-5p mimic significantly increased osteogenic differentiation capacity and p-PI3K and p-Akt protein levels. Luciferase activity in ADSCs co-transfected of miR-1249-5p mimic with PDX1-WT reporter plasmids was remarkably decreased, but there was no obvious change in miR-1249-5p mimic with PDX1-MUT reporter plasmids co-transfection group. Overexpression PDX1 could partially reverse the promotion effects of miR-1249-5p on osteogenesis of ADSCs. CONCLUSION: In conclusion, miR-1249-5p promotes osteogenic differentiation of ADSCs by targeting PDX1 through the PI3K/Akt signaling pathway.

[Identification and characteristics of multiple agrometeorological disaster of maize in Liaoning Province, China]. / 辽宁省玉米复合农业气象灾害判识及特征.

Multiple agrometeorological disaster (MAD) occurs simultaneously in maize production. In order to ascertain the occurrence regularity and characteristics of MAD of maize in Liaoning Pro-vince, we defined and classified MAD, identified MAD of 50 meteorological stations in the maize growing season of Liaoning Province from 1961 to 2017, and examined the effects of MAD on maize yield in typical years. The results showed that the occurrence range of MAD was higher in most years from 1961 to 2017 than that of single agrometeorological disaster (SAD), and that the occurrence frequency of MAD was higher in most areas than that of SAD. The major MAD in Liaoning Province was drought in multiple periods (M1-D), followed by the combination of drought and delayed cold damage (M2-DC). The occurrence range of M1-D showed an upward trend from 1961 to 2017, whereas other MAD types showed a downward trend. After analyzing the occurrence of MAD in the typical years of maize yield reduction, we found that the occurrence frequency of M1-D and M2-DC was higher.

[Application of evaporative demand drought index (EDDI) in drought identification of Liaoning Province, China]. / 蒸发需求干旱指数(EDDI)在辽宁省干旱识别中的应用.

The evaporative demand drought index (EDDI) is a multi-scale drought index developed from the atmospheric evaporation demand (E0). EDDI is independent of precipitation and suitable to different underlying surfaces, which can well capture water stress signals at different time scales. Based on the meteorological observation data at 52 stations in Liaoning Province from 1961 to 2018, we estimated daily E0, calculated EDDI at six time scales (annual, growing season, spring, summer, autumn and winter), and further identified the interannual variability of drought occurrence in Liaoning Province for the past 58 years. The results showed that EDDI had obvious interannual variation, with two high concentration periods in multiple time scales. In the 1960s, when there were many years and serious drought in Liaoning Province, high EDDI values were concentrated at the five time scales (annual, growing season, spring, autumn and winter). 2014-2018 was another relatively concentrated period of EDDI high value at all time scales except winter. In 1981-1982, the values of EDDI were high at the time scales of the annual, growth season, summer and autumn. The periods of 1963-1965 (except summer), 1972-1973 (growth season, summer), 1989-1990 (annual, growth season, spring and winter), 1997-1998 (annual, growth season and summer), 2004-2005 (spring and winter) and 2013-2014 (annual, growth season and autumn) occurred abrupt alternation from dry to wet or from wet to dry. In 1985-1987, 1993-1995 and 2005-2013, Liaoning Province had obvious dry gaps.

[Clinical characteristics of ZHU Dan-xi's acupuncture and moxibustion].

The clinical characteristics of ZHU Dan-xi 's acupuncture and moxibustion in the aspects of syndrome differentiation based on meridian and collateral and the techniques of acupuncture and moxibustion were explored by analyzing and summarizing ZHU Dan-xi's clinical experience in acupuncture and moxibustion practice. ZHU Dan-xi pointed out a compound symptoms with the three yin and three yang of hand and foot meridians, which enriches the connotation of the diagnosis and treatment on base of the meridian-collateral theory. In clinical practice, the therapeutic method with acupuncture and moxibustion is combined with herbal medicine. He believed that acupuncture is mostly used for reducing rather than reinforcing purpose. Hence, the bloodletting technique of acupuncture is commonly used. The moxibustion therapy is applicable for all of the conditions of deficiency, excess, cold and heat. In clinical practice, moxibustion is used for heat syndrome and acute syndrome by reducing heat, removing toxin and regaining consciousness. The timing of moxibustion should be considered specifically in the treatment for tonifying yang, generating yin, reducing heat and removing toxin. The unique characteristics of ZHU Dan-xi 's experience provide the reference for the clinical practice of acupuncture and moxibustion in the later generations.

A revised classification of Chinese Davalliaceae based on new evidence from molecular phylogenetics and morphological characteristics.

Although the phylogenetic framework of Davalliaceae is known, the classification of Chinese Davalliaceae is still controversial. In this study, a molecular phylogenetic tree of 60 accessions, including 29 species produced in China, was constructed using five plastid DNA markers-atpB, atpB-rbcL, rbcL, rbcL-accD, and accD. New data on studied specimens, field investigations, and scanning electron microscopy analysis of leaf epidermis and spores were used to reclassify Chinese Davalliaceae. The taxonomic position of Davallia canariensis was confirmed based on new evidence and a new key to sections of Chinese Davalliaceae was proposed. The taxonomically controversial genus Paradavallodes was confirmed as a polyphyletic group, and it was assigned to Davallia sect. Trogostolon and Davallia sect. Davallodes. Further, species endemic to China were delimited, 21 species were admitted to six sections of Davallia, two new combinations were proposed, two new synonyms were defined and a new key to Chinese species of Davalliaceae was presented.

Microrna-139-5p inhibits epithelial-mesenchymal transition and fibrosis in post-menopausal women with interstitial cystitis by targeting LPAR4 via the PI3K/Akt signaling pathway.

The study explores whether miR-139-5p targeting LPAR4 affects epithelial-mesenchymal transition (EMT) and fibrosis in post-menopausal women with interstitial cystitis (IC) via the PI3K/Akt signaling pathway. Bladder tissues of IC and normal bladder tissues were collected. The pathology of bladder tissues was observed by HE, Masson and Picrosirius red staining. LPAR4 positive expression rate were determined by IHC. ELISA was performed to detect the levels of IL-6, IL-8, IL-10, and TNF-α. Rat IC models were randomized into seven different groups. miR-139-5p, LPAR1, LPAR2, LPAR3, LPAR4, LPAR5, P13K, Akt, E-cadherin, N-cadherin, Vimentin, TGF-ß1, and CTGF expression were determined by RT-qPCR and Western blotting. Dual luciferase reporter gene assay verified that LPAR4 is a target gene of miR-139-5p. Fibrosis was a pathological manifestation of IC. The IC group showed higher LPAR4, PI3K, Akt, p-PI3K, p-Akt, N-cadherin, Vimentin, TGF-ß1, and CTGF expression but lower miR-139-5p and E-cadherin expression than the normal group. The levels of IL-6, IL-8, IL-10, and TNF-α expression decreased while HB-EGF increased in the IC group in comparison of the normal group. Compared with the blank and NC groups, E-cadherin expression was increased in the miR-139-5p mimic and siRNA-LPAR4 groups, while LPAR4, PI3K, Akt, p-P13K, p-Akt, N-cadherin, Vimentin, TGF-ß1, and CTGF expression were decreased. An opposite trend was found in the miR-139-5p inhibitor group. The miR-139-5p decreased in the miR-139-5p inhibitor + siRNA-LPAR4 and miR-139-5p inhibitor + wortmannin groups. Conclusively, miR-139-5p targeting LPAR4 inhibits EMT and fibrosis in post-menopausal IC women through the PI3K/Akt signaling pathway.

The introduction of the Barbier reaction into polymer chemistry.

The Barbier reaction, a widely utilized reaction for carbon-carbon bond formation, has played important roles in modern organic chemistry for more than a century. Here, we show its successful introduction to polymer chemistry. Through one-pot Barbier polyaddition (both A2+B2 type and AB type) of monomers containing an organic halide and a benzoyl group, a series of phenylmethanol group containing polymers, including polymonophenylmethanol (PMPM), polydiphenylmethanol (PDPM), and polytriphenylmethanol (PTPM), have been synthesized. Para-PTPM exhibits interesting aggregation-induced emission, tunable thermo-responsive over a wide temperature range, sensory, luminescence enhancement of fluorescent dye in solid-state and processing properties. This significantly expands the libraries of monomer and polymer, and opens up an avenue for the design and application of functional polymer materials.

Pincushion of Tubule Discovery and Tubular Morphology Landscape Establishment of Block Copolymer Self-Assemblies.

Block copolymer (BCP) self-assembly is a versatile technique in the preparation of polymeric aggregates with varieties of morphologies. However, its morphology library is limited. Here, the discovery of pincushion of tubules is reported for the first time, via BCP self-assembly of poly(4-vinylpyridine)-b-polystyrene (P4VP-b-PS) with very high molecular weight (500 kDa) and asymmetry (2 mol% P4VP). The investigation confirms the importance of core-forming block length on morphology control of BCP self-assemblies, especially with respect to tubular structures. The morphology landscape of tubular structures is successfully established, where dumbbell of tubule, tubule, loose clew of tubules, tight clew of tubules, and pincushion of tubules can be prepared by adjusting the core-forming block length. This work therefore expands the structure library of BCP self-assemblies and opens up a new avenue for the further applications of these tubular materials.

Monitoring menstrual cycle, gestation and lactation by measuring urinary oestradiol and progesterone in the captive golden snub-nosed monkey (Rhinopithecus roxellanae).

The golden snub-nosed monkey is an endangered species and study of its reproductive physiology is crucial for the species' breeding programs. Urine samples (770) from 5 mature female golden snub-nosed monkeys were collected in the Shengnongjia Nature Reserve between October 2013 and December 2014 to monitor their menstrual cycle, gestation, and lactation. The concentrations of oestradiol (E2) and progesterone (P4) in the samples were measured by Chemiluminescent Microparticle Immunoassay (CMIA), and the hormone concentrations were indexed to creatinine levels to compensate for differences in water content. The results showed that the E2 and P4 levels during the breeding season were significantly higher than those during the non-breeding season (P<0.01). The length of the menstrual cycle during the breeding season was 24.29±0.71days (mean±SEM) with a follicular cycle of 8.33±0.62days and luteal cycle of 15.27±0.83days. In addition, the levels of E2 and P4 began to rise on day 14 and day 10 after conception and remained at a high level until parturition. However, the E2 and P4 levels during lactation were lower than those during gestation (P<0.01). In summary, this study extends our knowledge regarding the basic reproductive physiology of golden snub-nosed monkeys, which could play an important role in the expansion of this species' population.

Expanding the morphology library of block copolymer self-assemblies with clews of tubules.

The morphology library of block copolymer (BCP) self-assemblies is limited, especially as far as tubular structures are concerned. Here, the morphology of clews of tubules is discovered for the first time by self-assembly of P4VP-b-PS BCPs with both high asymmetry and very high molecular weight, which successfully expands the morphology library of BCP self-assemblies.

RAFT-Polymerization-Induced Self-Assembly and Reorganizations: Ultrahigh-Molecular-Weight Polymer and Morphology-Tunable Micro-/Nanoparticles in One Pot.

A one-pot method is introduced for the successful synthesis of narrow-distributed (D = 1.22) vinyl polymer with both ultrahigh molecular weight (UHMW) (M w = 1.31 × 106 g mol-1 ) and micro-/nanomorphology under mild conditions. The method involves the following four stages: homogeneous polymerization, polymerization-induced self-assembly (PISA), PISA and reorganization, and PISA and multiple reorganizations. The key points to the production of UHMW polystyrene are to minimize radical termination by segregating radicals in different nanoreactors and to ensure sufficient chain propagation by promoting further reorganizations of these reactors in situ. This method therefore endows polymeric materials with the outstanding properties of both UHMW and tunable micro-/nanoparticles under mild conditions in one pot.

GFOD1 and peejar are promising markers for clear-cell renal cell carcinoma disease progression.

Clear cell renal cell carcinoma (ccRCC) is a common genitourinary malignancy. The molecular pathogenesis of ccRCC remains unclear and biomarkers for daily practice were still limited. We performed an integrative analysis of two public ccRCC microarray datasets, E-GEOD-22541 and E-MTAB-1050, The candidate differential expression genes (DEG) were then confirmed in the E-GEOD-53757 dataset. In addition, an independent cohort of 50 ccRCC and 36 non-tumor kidney tissues were analyzed to examine the selected DGEs by qRT-PCR. We identified and validated two DEGs, namely GFOD1 and peejar, which were significantly up-regulated in ccRCC compared with normal renal tissues (p < 0.001). Moreover, the expression of these two genes are related to histological grade and stage and decrease of their expression correlated with disease progression (p < 0.05). Furthermore, we found the expression of peejar was positively correlated with the expression of GFOD1 in ccRCC tissue, with Pearson correlation coefficiency reaching 0.939 (p < 0.001). GFOD1 and peejar were novel genes correlated with ccRCC disease progression and patients' poor prognosis.

Versatile Method to Expand the Morphology Library of Block Copolymer Solution Self-Assemblies with Tubular Structures.

Self-assembly of block copolymers (BCPs) in solution is a powerful technology to achieve a broad range of structures, such as spheres, cylinders, vesicles, and other hierarchical structures. However, the BCP self-assembly library is limited, especially with respect to tubular structures. Here we show a versatile strategy to expand the morphology library of block copolymer solution self-assemblies with tubular structures (including tubular dumbbells and tubules) via self-assembly of the most common diblock copolymers P4VP-b-PS BCPs in methanol. No special chemistry is needed in this strategy, which proves the universality of this method. The novelty of the strategy is to keep the BCPs both highly asymmetric and with very high molecular weight. The underlying formation mechanism and kinetics of these tubular structures were elucidated. The prepared tubular structures expand the structure library of BCP solution self-assemblies and open up a new avenue for the further applications of a variety of tubular materials.

Renal AML with inferior vena cava thrombus treated by workbench surgery and autotransplantation.

Renal angiomyolipoma may sometimes require surgical intervention. In this paper, we present a case of renal angiomyolipoma which infiltrated the sinus and extended into the inferior vena cava. He was successfully treated with a combined approach of laparoscopic radical nephrectomy, extracorporeal workbench tumor resection, and autotransplantation. Three months postoperatively, no evidence of tumor recurrence or presence of thrombus in the inferior vena cava was noted. Our experience represents the successful application of a combined nephron-sparing approach in the management of angiomyolipoma with extension into a major blood vessel.

[Influence of the Composition of the Initial Mixtures on the Physicochemical and Biological Properties and Spectral Characteristics of Composts].

In this work, biogas residues, the remnant of the anaerobic digestion, was used for composting with livestock manure as the co-substrate. It is important for improving the soil quality in China, because the negative influence of biogas residues being utilized directly as organic fertilizer (a mainstream way of disposing biogas residues in China) on the soil could be eliminated or mitigated via composting. The composition of composting substrate has a great influence on the composting process. To explore the influence of the composition of the initial mixtures on the physicochemical properties and spectroscopic characteristics of composts, fifteen co-composting of biogas residue, pig manure and chicken manure, with different material ratios, were carried out. Physicochemical and biological indicators were determined. Meanwhile, spectroscopic methods, such as UV-Vis, synchronous fluorescence and 3D-EEM spectra were used for identifying characteristic spectral parameters companied with FRI and PARAFAC. Therefore, spectroscopic characteristics of composts were characterized. The relationship between physicochemical properties of composts and the composition of the initial mixtures was established using CCA. Similarly, that between spectroscopic characteristics of composts and the composition of the initial mixtures was also established. The results showed that: physicochemical properties of composts exhibits a significant correlation with the composition of the initial mixtures. A significant correlation between spectroscopic characteristics of composts and the composition of the initial mixtures was also observed. In the two CCA, the former four axes account for 83.9% and 97.5% of the total sample variation. The influence of enviro nmental factors on physicochemical properties of composts was in the order of pig manure amount>chicken manure amount>biogas residue amount and that on spectroscopic characteristics of composts was in the order of biogas residue amount>pig manure amount>chicken manure amount. Carbon-rich raw materials favor the maturation of compost. A high proportion of nitrogen-rich raw materials does not lead to the accumulation of ammonia in compost. A low proportion of biogas residue favors the formation of humic substances during the co-composting of biogas residue and livestock manure. In summary, the evaluation of compost fermentation effect should synthetically consider physic-chemical, biological indicators and spectral parameters instead of a single index.

Treatment of renal cell carcinoma with a level III or level IV inferior vena cava thrombus using cardiopulmonary bypass and deep hypothermic circulatory arrest.

BACKGROUND: The aim of this study was to investigate the minimally invasive cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA) approach in the management of renal cell carcinoma (RCC) with level III or IV inferior vena cava (IVC) thrombus and evaluate the survival outcomes. METHODS: We performed a retrospective analysis on 32 RCC patients with IVC thrombus that underwent nephrectomy and thrombectomy via the minimally invasive CPB/DHCA approach between January 2007 and December 2013. Perioperative variables (for example, operative time, CPB duration, and circulatory arrest duration), estimated blood loss, hospital stay, perioperative complications, and survival data were recorded and analyzed. RESULTS: Thirty-two patients (median age: 56 years) were treated surgically using the CPB and DHCA approach for RCC with a level III (n=25) or level IV (n=7) tumor thrombus. The median operation time was 360 min (interquartile range (IQR): 300 to 435 min) with median CPB and DHCA durations of 149 min and 23 min, respectively. The median estimated blood loss was 2,500 ml. Four complications were observed but no deaths occurred perioperatively. The median follow-up was 25 months (range: 4 to 64 months). The mean overall survival (OS) was 28.2±4.6 months while the disease-free survival (DFS) was 19.5±11.6 months. In patients with M0 disease, ten patients developed metastases and were treated with sorafenib as an adjuvant therapy. The mean OS and DFS of this subgroup were 25.4±12.8 months and 16.0±14.2 months, respectively. CONCLUSIONS: Radical nephrectomy and thrombectomy using CPB and DHCA to treat RCC is a relatively safe approach associated with low morbidity and mortality. This minimally invasive procedure may help minimize surgical trauma and improve perioperative outcomes.

Identification of the relationship between Chinese Adiantum reniforme var. sinense and Canary Adiantum reniforme.

BACKGROUND: There are different opinions about the relationship of two disjunctively distributed varieties Adiantum reniforme L. var. sinense Y.X.Lin and Adiantum reniforme L. Adiantum reniforme var. sinense is an endangered fern only distributed in a narrowed region of Chongqing city in China, while Adiantum reniforme var. reniforme just distributed in Canary Islands and Madeira off the north-western African coast. To verify the relationship of these two taxa, relative phylogenetic analyses, karyotype analyses, microscopic spore observations and morphological studies were performed in this study. Besides, divergence time between A. reniforme var. sinense and A. reniforme var. reniforme was estimated using GTR model according to a phylogeny tree constructed with the three cpDNA markers atpA, atpB, and rbcL. RESULTS: Phylogenetic results and divergence time analyses--all individuals of A. reniforme var. sinense from 4 different populations (representing all biogeographic distributions) were clustered into one clade and all individuals of A. reniforme var. reniforme from 7 different populations (all biogeographic distributions are included) were clustered into another clade. The divergence between A. reniforme var. reniforme and A. reniforme var. sinense was estimated to be 4.94 (2.26-8.66) Myr. Based on karyotype analyses, A. reniforme var. reniforme was deduced to be hexaploidy with 2n = 180, X = 30, while A. reniforme var. sinense was known as tetraploidy. Microscopic spore observations suggested that surface ornamentation of A. reniforme var. reniforme is psilate, but that of A. reniforme var. sinense is rugate. Leaf blades of A. reniforme var. sinense are membranous and reniform and with several obvious concentric rings, and leaves of A. reniforme var. reniforme are pachyphyllous and coriaceous and are much rounder and similar to palm. CONCLUSION: Adiantum reniforme var. sinense is an independent species rather than the variety of Adiantum reniforme var. reniforme. As a result, we approve Adiantum nelumboides X. C. Zhang, nom. & stat. nov. as a legal name instead of the former Adiantum reniforme var. sinense. China was determined to be the most probable evolution centre based on the results of phylogenetic analyses, divergence estimation, relative palaeogeography and palaeoclimate materials.

Star-shaped poly(L-lactide)-b-poly(lactobionamidoethyl methacrylate) with porphyrin core: synthesis, self-assembly, singlet oxygen research and recognition properties.

Star-shaped porphyrin-cored poly(L-lactide)-b-poly(lactobionamidoethyl methacrylate) block copolymers (SPPLA-b-PLAMA) were synthesized via RAFT of unprotected Lactobionamidoethyl methacrylate (LAMA) in 1-methyl-2-pyrrolidinone (NMP) solution at 70 °C. The structure of this as-synthesized SPPLA-b-PLAMA block copolymer was thoroughly studied by nuclear magnetic resonance spectroscopy, gel permeation chromatography (GPC), and Fourier transforms infrared. Moreover, under the irradiation, such SPPLA-b-PGAMA copolymer exhibits efficient singlet oxygen generation (0.17) and indicates high fluorescence quantum yields (0.20). Notably, with UV-vis investigation, SPPLA-b-PLAMA showed a very specific recognition with RCA120 lectin. This will not only provide potentially prophyrin-cored star-shaped SPPLA-b-PLAMA block copolymers for targeted photodynamic therapy, but also improve the physical, biodegradation, biocompatibility properties of PLA-based biomaterials.

TNF/TNFR1 pathway and endoplasmic reticulum stress are involved in ofloxacin-induced apoptosis of juvenile canine chondrocytes.

BACKGROUND AND PURPOSE: Quinolones cause obvious cartilaginous lesions in juvenile animals by chondrocyte apoptosis, which results in the restriction of their use in pediatric and adolescent patients. Studies showed that chondrocytes can be induced to produce TNFα, and the cisternae of the endoplasmic reticulum in quinolone-treated chondrocytes become dilated. We investigated whether TNF/TNFR1 pathway and endoplasmic reticulum stress (ERs) are involved in ofloxacin (a typical quinolone)-induced apoptosis of juvenile canine chondrocytes. EXPERIMENTAL APPROACH: Canine juvenile chondrocytes were treated with ofloxacin. Cell survival and apoptosis rates were determined with MTT method and flow cytometry, respectively. The gene expression levels of the related signaling molecules (TNFα, TNFR1, TRADD, FADD and caspase-8) in death receptor pathways and main apoptosis-related molecules (calpain, caspase-12, GADD153 and GRP78) in ERs were measured by qRT-PCR. The gene expression of TNFR1 was suppressed with its siRNA. The protein levels of TNFα, TNFR1 and caspase-12 were assayed using Western blotting. KEY RESULTS: The survival rates decreased while apoptosis rates increased after the chondrocytes were treated with ofloxacin. The mRNA levels of the measured apoptosis-related molecules in death receptor pathways and ERs, and the protein levels of TNFα, TNFR1 and caspase-12 increased after the chondrocytes were exposed to ofloxacin. The downregulated mRNA expressions of TNFR1, Caspase-8 and TRADD, and the decreased apoptosis rates of the ofloxacin-treated chondrocytes occurred after TNFR1-siRNA interference. CONCLUSIONS AND IMPLICATIONS: Ofloxacin-induced chondrocyte apoptosis in a time- and concentration-dependent fashion. TNF/TNFR1 pathway and ERs are involved in ofloxacin-induced apoptosis of juvenile canine chondrocytes in the early stage.