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Dabieshan tick virus (DBTV) is a newly identified arbovirus, first detected in Haemaphysalis longicornis collected from Hubei Province in 2015. It has been confirmed that DBTV is widely distributed in Shandong Province, China. However, its entomological and epidemiological features remain to be further explored, particularly the feasibility of transovarial transmission. Our research tries to explain the possibility of transovarial transmission of DBTV from engorged female ticks to their offspring. All engorged female adult ticks were sampled from domestic sheep and allowed to lay eggs and hatch in appropriate laboratory conditions. All engorged ticks, larvae and unhatched eggs were classified into pools for nucleic acid extraction and DBTV RNA detection. According to the results of qRT-PCR, the positive rate of DBTV was 6.25% (8/128) in engorged female ticks, 3.57% (1/28) in eggs and 5% (3/60) in larvae pools, respectively. Phylogenetic analysis indicated that DBTV isolates from larvae were similar to those from maternal ticks with more than 99.5% homology, and DBTV was relatively conservative in evolution. Our findings are the first to provide molecular evidence of potential transovarial transmission of DBTV among H. longicornis. Nonetheless, the transovarial transmission of DBTV in frequency and proportion occurring in nature deserves further investigation. [ABSTRACT FROM AUTHOR]

A metal-free and oxidant-free acid-promoted DMSO activation and subsequent reaction is reported. In this protocol, two molecules of DMSO are activated by HOAc and serve as dual synthons which react with ortho -hydroxyacetophenones, affording 3-(methylthiomethyl)chroman-4-ones in moderate to good yields with high selectivity. [ABSTRACT FROM AUTHOR]

Background. Various techniques have been described for repairing cyclodialysis clefts, but there is no consensus regarding the optimal treatment. This study investigated the clinical efficacy of a novel surgical approach that is used to manage traumatic cyclodialysis. Methods. We prospectively enrolled 7 patients (7 eyes) with traumatic cyclodialysis of the concomitant lens and other vitreous diseases. Ultrasound biomicroscopy was used to diagnose cyclodialysis, and all eyes underwent pars plana vitrectomy with air endotamponade. The main outcome measures were postoperative anatomical success rates, best-corrected visual acuity (BCVA), and intraocular pressure (IOP). Results. All patients were male, and their age ranged from 46 to 64 years (mean: 54.3 years). After the surgical intervention, the extent of the cyclodialysis cleft ranged from 1 to 4 clock hours (mean: 2.3 clock hours) and the detached ciliary body of all cases was completely restored; the anatomical success rate was 100%. The BCVA significantly increased from 1.40 ± 0.49 to 0.42 ± 0.31 (P = 0.002). The IOP increased from 8.91 ± 1.77 to 14.67 ± 6.38, but the difference was not significant (P = 0.056). The postoperative IOP of most patients was temporarily elevated or lowered after surgery. At the last follow-up, there were still two abnormal cases, including one with ocular hypertension and one with hypotony. Conclusions. This study revealed that vitrectomy with air endotamponade is an effective and minimally invasive alternative surgical approach for small traumatic cyclodialysis clefts. [ABSTRACT FROM AUTHOR]

Background: Localized `and disseminated Nocardia farcinica infection is frequently reported in immunocompromised patients. However, orbital nocardiosis is rare, and, to our knowledge, traumatic orbital nocardiosis that affects the brain has never been described. Here, we report a case of traumatic orbital and intracranial N. farcinica infection in an immunocompetent patient.Case Presentation: A 35-year-old man, who was immunocompetent, to the best of our knowledge and as per the absence of immunodeficiency symptoms, with orbital trauma caused by the penetration of a rotten bamboo branch developed lesions in the orbit and brain. Subsequently, he underwent debridement and received broad-spectrum antibiotic therapy, but orbital infection occurred, with drainage of pus through the sinus tract. The patient then underwent endoscope-assisted local debridement. Bacterial culture of the sinusal pus was positive for N. farcinica, and a combined intracranial infection had developed. The disease was treated effectively by trimethoprim-sulfamethoxazole and ceftriaxone sodium therapy. The patient remained infection free and without complications at the 14-month follow-up.Conclusions: Traumatic orbital and intracranial infection caused by N. farcinica is a rare infectious disease, and atypical presentations easily lead to misdiagnosis. When a patient presents with an atypical orbital infection that is unresponsive to empirical broad-spectrum antibiotics, along with suspicious neurologic symptoms, Nocardia infection should be considered. Identification by bacterial culture is the gold standard. Complete local debridement and appropriate antibiotic treatment are keys to the treatment of the disease. [ABSTRACT FROM AUTHOR]

Purpose. To investigate the frequency and patterns of the residual vitreous cortex (RVC) at the fovea after posterior vitreous detachment (PVD) during vitrectomy after ocular trauma and the risk factors associated with its occurrence. Methods. A cross-sectional, multicenter, and observational study was conducted in 72 consecutive patients who underwent pars plana vitrectomy after ocular trauma. In patients with PVD after vitrectomy, RVC patterns were visualized using triamcinolone acetonide staining and were classified as diffuse or focal. A multivariate logistic regression analysis was performed to evaluate the association between RVC and various factors, such as the patient's age, preoperative visual acuity, days after injury, the existence of spontaneous PVD, and the type of injury prior to vitrectomy. Results. Of the 72 eyes with trauma, 35 eyes (48.6%) showed RVC on the macula, of which 19 (54.3%) were of the diffuse type and 16 (45.7%) were of the focal type. A multivariate logistic regression analysis showed that age (OR = 0.933, P=0.025) and days after injury (OR = 0.862, P=0.013) had a significant impact on RVC. Conclusions. RVC at the fovea is very common after spontaneous or surgical PVD during vitrectomy. Younger patients are more likely to show RVC if vitrectomy is performed soon after injury. [ABSTRACT FROM AUTHOR]

Background and Aims Salinity affects the bioavailability of cadmium (Cd) in soils and Cd accumulation in plants, but the associated mechanisms remain unclear. This study aimed to assess the metabolic response to NaCl and Cd and the relationship between metabolites and Cd accumulation in the halophyte Carpobrotus rossii, which has potential for Cd phytoextraction. Methods Plants were grown in nutrient solution with 0–400 m m NaCl in the presence of 5 or 15 µ m Cd, with varied or constant solution Cd2+ activity. Plant growth and Cd uptake were measured, and the accumulation of peptides, and organic and amino acids in plant tissues were assessed. Key Results The addition of NaCl to Cd-containing solutions improved plant growth along with 70–87 % less shoot Cd accumulation, resulting from decreases in Cd root uptake and root-to-shoot translocation irrespective of Cd2+ activity in solutions. Moreover, Cd exposure increased the concentration of phytochelatins, which correlated positively with Cd concentrations in plants regardless of NaCl addition. In comparison, Cd inhibited the synthesis of organic acids in shoots and roots in the absence of NaCl, but increased it in shoots in the presence of NaCl. While Cd increased the concentrations of amino acids in plant shoots, the effect of NaCl on the synthesis of amino acids was inconsistent. Conclusions Our data provide the first evidence that NaCl decreased Cd shoot accumulation in C. rossii by decreasing Cd root uptake and root-to-shoot translocation even under constant Cd2+ activity. The present study also supports the important role of peptides and organic acids, particular of phytochelatins, in Cd tolerance and accumulation although the changes of those metabolites was not the main reason for the decreased Cd accumulation. [ABSTRACT FROM AUTHOR]

Nitrogen fertilization has been shown to improve Cd uptake by plants but there is little information on the effect of N form. This study examined the effects of N form on Cd bioavailability and phytoextraction in two soils differing in pH. Plants of halophytic species Carpobrotus rossii were grown in an acidic Sodosol [pH (CaCl 2 ) 4.9] and a neutral Vertosol (pH 7.2) spiked with 20 mg kg −1 Cd as CdCl 2 . Three N forms, KNO 3 , (NH 4 ) 2 SO 4 and (NH 2 ) 2 CO at a rate of 24 mg N kg −1 were applied at weekly intervals, together with nitrification inhibitor dicyanodiamide. Cadmium availability was measured, and Cd speciation in the rhizosphere analysed using synchrotron-based X-ray absorption spectroscopy. The uptake, translocation and accumulation of Cd in plants were also assessed. The reduced N forms (NH 4 + and urea), compared to NO 3 − -N, decreased rhizosphere pH by 0.25 units in Sodosol and 0.72 units in Vertosol, but decreased Cd-phosphate (by 23%) only in the Vertosol. Moreover, the reduced N forms increased the extractable Cd concentration in the rhizosphere of the Vertosol by 92% and of the Sodosol by 14%. They increased root Cd concentration by 70% and Cd uptake per unit root length by 40% in the Vertosol, and increased the translocation of Cd from the roots to the shoots by 76% in the Sodosol. The results suggest that the supply of NH 4 + -based N favors Cd phytoextraction in C. rossii . [ABSTRACT FROM AUTHOR]

Diphenylarsinic acid (DPAA) is a major contaminant in environments polluted by chemical weapons and abandoned after World Wars I and II and poses high risks to biota but remediation methods for this contaminant are rare. Here, the photodegradtion of DPAA was studied under high-pressure Hg lamp irradiation. DPAA was degraded completely into inorganic arsenic species in 30 min under UV-C irradiation. The photodegradation of DPAA depended mainly on its direct photolysis through excited-state DPAA. By contrast, the generation of 1 O 2 during the photodegradation of DPAA was confirmed by electron paramagnetic resonance (EPR) studies, but 1 O 2 had little effect on the photodegradation of DPAA. Phtotodegradation of DPAA was also studied in soil leachates and groundwater and the photolytic rate of DPAA was controlled by the total organic carbon (TOC) content in soil leachates and by the NO 3 − concentration in groundwater. Finally, studies on the effects of common solutes on the photodegradation of DPAA show that Cl − can increase the photolytic rate of DPAA by prolonging the lifetime of excited-state DPAA. Moreover, NO 3 − , NO 2 − , and humic acid (HA) can decrease the photolytic rate of DPAA by suppressing the production of excited-state DPAA. This research shows the detailed mechanism of DPAA photodegradation and provides a new and effective method for DPAA decontamination. [ABSTRACT FROM AUTHOR]

Substrate‐induced synthesis of 6H‐Chromeno[4,3‐b]quinolin‐6‐ones has been developed directly from anilines, 4‐hydroxycoumarins and DMSO under air without any catalysts and additives in one pot. This protocol highlights dual roles of 4‐hydroxycoumarins which were not only used as reactants but also activated DMSO to provide one‐carbon unit in the desired products. [ABSTRACT FROM AUTHOR]

A new method is described for calculating flare combustion efficiency (CE) and destruction and removal efficiency (DRE) using a numerical parametric model. The method combines key variables that affect flare performance including the flare vent gas net heating value (NHV), flare design, flow rate, exit velocity, and inert gas composition, alongside the environmental influence of crosswind speed. Each effect is characterized using a parametric model derived from experimental testing data and computational fluid dynamics (CFD). The inclusion of CFD allows the model to be extended into the high-wind conditions that cannot be adequately controlled for in empirical testing yet represent some of the most challenging conditions in which to maintain good combustion. This new parametric model method (PMM) is coupled with ultrasonic flowmeters from which the molecular weight and net heating value of the flare gas can be derived using the vent gas speed of sound measurement. In doing so, this method provides a reliable continuous flare combustion efficiency measure that can be deployed at scale with minimum hardware updates. The system was verified using an extractive sampling method with tests conducted on three full-scale industrial flares including non-assisted, single-arm pressure-assisted, and multi-arm pressure-assisted flare designs. A total of seventy valid test points were carried out with varying flow rate and flare gas heating value, covering a CE range from 46–100%. The uncertainty of the method was assessed using both traditional error propagation and Monte Carlo methodology. The results from the new method agree with the extractive method to within 0.8% in the ≥98% DRE region where flares are expected to operate to limit the impacts of flaring as a source of methane as a greenhouse gas. Uncertainty analysis revealed that the larger DRE discrepancy for DRE ≤ 98% correlates to the measurement uncertainties for both methods. [ABSTRACT FROM AUTHOR]

Accurately measuring the combustion and destruction removal efficiency of flaring is important when accounting for methane emissions from oil and gas production. Despite this, the amount of experimental data from full-size flares is limited, especially for flares built without air or steam assistance. The use of a single destruction value of 98% is commonly applied. In this paper, we present new empirical measurements of flare efficiency using three common flare designs employed in upstream applications. Combustion products were analyzed using an extractive sampling method. The results demonstrate that whilst destruction efficiencies in excess of 98% are achievable, if the gas composition falls below a critical heating value of ~300 BTU/scf, the efficiency deteriorates leading to elevated methane emissions. This is further complicated by accurately measuring the flow of combustible gas and the impact of crosswinds. In an operational setting, continuous tracking of flare conditions is therefore a key resource in reducing methane emissions but further work is required to standardize how continuous performance tracking is evaluated if such measurements are to attain full traceability. [ABSTRACT FROM AUTHOR]

Federal Regulation 40 CFR §63.670 requires flare operators to specify smokeless design capacity for flares with no visible emissions. Alternatively, 96.5% combustion efficiency (CE) or 98% destruction efficiency must be achieved with threshold limits of minimum combustion zone net heating value (NHVcz) ≥ 270 British thermal unit/standard cubic feet (BTU/scf) for steam-assisted and net heating value dilution parameter (NHVdil) ≥ 22 BTU/ft2 for air-assisted flares. There is still no guarantee for smokeless flaring (SLF) or CE >96.5%. Robust response surface models developed in this study expressed %CE and %Opacity as a function of operating variables for air- and steam-assisted flares. Opacity and CE test data from 1983 to 2016 were analyzed. General quadratic models with transforms of CE and Opacity showed R2 > 0.90, and bivariate sigmoid models for CE showed R2 > 0.87. Two-dimensional (2D) contours illustrate the trends of major operating parameters. Operational setpoints at the incipient smoke point (ISP) and SLF were determined by solving the models subject to NHVcz and NHVdil threshold limits specifying Opacity at 3% (ISP) and 2% (SLF). The predicted steam/air assists/makeup fuel, NHVcz (or NHVdil), and CE at ISP and SLF conditions are compared with the experimental 1984 Environmental Protection Agency (EPA) and 2010 Texas Commission on Environmental Quality flare study ISP test data. These setpoints would help flare operators to establish ISP or SLF conditions either by adding makeup fuel to vent gas with low heating value or by minimizing the assist without adding makeup fuel for steam- and air-assisted flares. [ABSTRACT FROM AUTHOR]

Background and Aims Salt has been shown to affect Cd translocation and accumulation in plants but the associated mechanisms are unclear. This study examined the effects of salt type and concentration on Cd uptake, translocation and accumulation in Carpobrotus rossii. Methods Plants were grown in nutrient solution with the same Cd concentration or Cd2+ activity in the presence of 25 m m NaNO3, 12.5 m m Na2SO4 or 25 m m NaCl for ≤10 d. Plant growth and Cd uptake were measured and the accumulation of peptides and organic acids, and Cd speciation in plant tissues were analysed. Key Results Salt addition decreased shoot Cd accumulation by >50 % due to decreased root-to-shoot translocation, irrespective of salt type. Synchrotron-based X-ray absorption spectroscopy revealed that, after 10 d, 61–94 % Cd was bound to S-containing ligands (Cd–S) in both roots and shoots, but its speciation was not affected by salt. In contrast, Cd in the xylem sap was present either as free Cd2+ or complexes with carboxyl groups (Cd–OH). When plants were exposed to Cd for ≤24 h, 70 % of the Cd in the roots was present as Cd–OH rather than Cd–S. However, NaCl addition decreased the proportion of Cd–OH in the roots within 24 h by forming Cd–Cl complexes and increasing the proportion of Cd–S. This increase in Cd–S complexes by salt was not due to changes in glutathione and phytochelatin synthesis. Conclusions Salt addition decreased shoot Cd accumulation by decreasing Cd root-to-shoot translocation due to the rapid formation of Cd–S complexes (low mobility) within the root, without changing the concentrations of glutathione and phytochelatins. [ABSTRACT FROM AUTHOR]

Dimethylglycine sodium salt (DMG-Na) has exhibited excellent advantages in animal experiments and human health. The present study aimed to investigate the effects of dietary supplementation with 0.1% DMG-Na on the growth performance, hepatic antioxidant capacity, and mRNA expression of mitochondria-related genes in low birth weight (LBW) piglets during weaning period. Sixteen piglets with normal birth weight (NBW) and 16 LBW piglets were fed either a basal diet or a 0.1% DMG-Na supplemented diet from age of 21 to 49 d. Blood and liver samples were collected at the end of the study. The results showed that compared with NBW piglets, LBW piglets exhibited greater (P < 0.05) alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase activities in the serum. LBW decreased (P < 0.05) the activity of glutathione peroxidase and increased (P < 0.05) the contents of malondialdehyde and H2O2 in liver. DMG-Na supplementation increased (P < 0.05) body weight gain, feed intake, and feed efficiency, decreased (P < 0.05) ALT and AST activities, and reduced the content of H2O2 in LBW piglets. LBW piglets had downregulated (P < 0.05) mRNA expression of thioredoxin 2, thioredoxin reductases 2, and nuclear respiratory factor-1 (Nrf1) in the liver. However, DMG-Na supplementation increased (P < 0.05) mRNA expression of Nrf1 in the liver. In conclusion, DMG-Na supplementation has beneficial effects in alleviating LBW-induced hepatic oxidative damage and changed mitochondrial genes expression levels, which is associated with increased antioxidant enzyme activities and up-regulating mRNA gene abundance. [ABSTRACT FROM AUTHOR]

Background and aims: Interactions between Cd and Zn occur in soils and plants but are inconsistent. This study examined how Cd/Zn interactions influence the growth of Carpobrotus rossii (Haw.) and the accumulation of Cd and Zn in plants.Methods: Plants were grown in nutrient solutions containing 5-100 μM Zn and 0, 5 or 15 μM Cd. Plant growth and tissue concentrations were measured, and the speciation of Zn within the plant tissues determined using synchrotron-based X-ray absorption spectroscopy.Results: There was an additive negative interaction between Cd and Zn on root growth. Only the highest level of Zn (100 μM) decreased Cd concentrations in root and shoot tissues (by 40-64%), whilst 100 μM Zn enhanced Cd translocation at 5 μM Cd but decreased it at 15 μM Cd. In contrast, both 5 and 15 μM Cd decreased Zn concentrations in root and shoot tissues but increased Zn translocation by 30-90%. This interaction was not associated with changes in Zn speciation within the plants, with most Zn associated with oxalate (48-87%).Conclusions: The presence of Zn and Cd resulted in an additive negative effect on root growth, but an antagonistic pattern in their accumulation in shoots of C. rossii. [ABSTRACT FROM AUTHOR]

Bacteriophages substantially contribute to bacterial mortality in the ocean and play critical roles in global biogeochemical processes. Alteromonas is a ubiquitous bacterial genus in global tropical and temperate waters, which can cross-protect marine cyanobacteria and thus has important ecological benefits. However, little is known about the biological and ecological features of Alteromonas phages (alterophages). Here, we describe a novel alterophage vB_AmeP-R8W (R8W), which belongs to the Autographiviridae family and infects the deep-clade Alteromonas mediterranea. R8W has an equidistant and icosahedral head (65 ± 1 nm in diameter) and a short tail (12 ± 2 nm in length). The genome size of R8W is 48,825 bp, with a G + C content of 40.55%. R8W possesses three putative auxiliary metabolic genes encoding proteins involved in nucleotide metabolism and DNA binding: thymidylate synthase, nucleoside triphosphate pyrophosphohydrolase, and PhoB. R8W has a rapid lytic cycle with a burst size of 88 plaque-forming units/cell. Notably, R8W has a wide host range, such that it can infect 35 Alteromonas strains; it exhibits a strong specificity for strains isolated from deep waters. R8W has two specific receptor binding proteins and a compatible holin–endolysin system, which contribute to its wide host range. The isolation of R8W will contribute to the understanding of alterophage evolution, as well as the phage–host interactions and ecological importance of alterophages. [ABSTRACT FROM AUTHOR]

Objective: We aimed to explore the prognostic value of primary tumor and specific metastases excision on survival among patients with stage IV colorectal cancer (CRC) in the Surveillance, Epidemiology, and End Results (SEER) database.Methods: Patients with stage IV CRC were selected using SEER database between 2010 and 2013. Survival rate was calculated according to the Kaplan-Meier method, and differences between curves were tested by the log-rank test. Cox proportional hazards model was used in the multivariable analysis.Results: Included in this study were 27 878 patients with distant metastatic CRC. Among the single organ site of metastatic CRC, patients with solitary metastasis of lung showed the highest median overall survival (OS). Both primary and metastatic sites surgical resection for patients with liver, lung, and simultaneous liver and lung metastases had better median OS. Age younger than 65 years, Asian and Pacific Islander, distal colon and rectum, and palliative primary tumor and metastatic lesions resection were associated with better OS after multivariate analysis. Palliative primary tumor and metastatic lesions resection had a significant survival benefit compared with nonsurgical group in selected patients.Conclusion: These findings support the use of preemptive surgery in the management of highly selected metastatic CRC patients. [ABSTRACT FROM AUTHOR]

The epidemiology and clinical outcome of gastrointestinal mucinous adenocarcinoma (MA) are not well illustrated. The present study aimed to explore the evolving epidemiology and prognostic factors that affect the survival of patients with MA in the gastrointestinal tract. A retrospective and population-based study was conducted to determine the annual age-adjusted incidence, overall survival (OS) and survival trend of gastrointestinal mucinous MA using nationally representative data from the Surveillance, Epidemiology, and End Results (SEER) program between 2000 and 2014. A Kaplan-Meier curve and a Cox proportional regression model were used to evaluate prognostic factors for this disease. Of the 51632 cases, females accounted for 50.5% (26058). The annual incidence of MA steadily decreased from 2000 to 2014. This trend occurred across all stages, grades and sites, apart from the appendix. In the SEER 18 registry grouping (2000–2014), the highest incidence was 3.333 per 100,000 persons for the colon. The median OS varied significantly between different primary sites, stages, grades, and age of clinical diagnosis, and the time period of diagnosis, according to a multivariable analysis. The five-year OS of gastrointestinal MA improved gradually between 2000 and 2014. The improvement in survival over the same interval was more pronounced in the subgroup of distant gastrointestinal MA. All sites along the alimentary tract, with the exception of the appendix, showed a decrease in the incidence of MA. Improved survival rates were observed for most of the gastrointestinal tract, especially for patients with advanced stage disease. MA in the upper gastrointestinal tract was less frequent but had poorer survival than colorectal MA. Clinicians should consider the primary tumour site when making therapeutic guidelines and treatment decisions for gastrointestinal MA. [ABSTRACT FROM AUTHOR]

Emissions from flares constitute unburned hydrocarbons, carbon monoxide (CO), soot, and other partially burned and altered hydrocarbons along with carbon dioxide (CO2) and water. Soot or visible smoke is of particular concern for flare operators/regulatory agencies. The goal of the study is to develop a computational fluid dynamics (CFD) model capable of predicting flare combustion efficiency (CE) and soot emission. Since detailed combustion mechanisms are too complicated for (CFD) application, a 50-species reduced mechanism, LU 3.0.1, was developed. LU 3.0.1 is capable of handling C4hydrocarbons and soot precursor species (C2H2, C2H4, C6H6). The new reduced mechanism LU 3.0.1 was first validated against experimental performance indicators: laminar flame speed, adiabatic flame temperature, and ignition delay. Further, CFD simulations using LU 3.0.1 were run to predict soot emission and CE of air-assisted flare tests conducted in 2010 in Tulsa, Oklahoma, using ANSYS Fluent software. Results of non-premixed probability density function (PDF) model and eddy dissipation concept (EDC) model are discussed. It is also noteworthy that when used in conjunction with the EDC turbulence-chemistry model, LU 3.0.1 can reasonably predict volatile organic compound (VOC) emissions as well. Implications: A reduced combustion mechanism containing 50 C1–C4species and soot precursors has been developed and validated against experimental data. The combustion mechanism is then employed in the computational fluid dynamics (CFD) of modeling of soot emission and combustion efficiency (CE) of controlled flares for which experimental soot and CE data are available. The validated CFD modeling tools are useful for oil, gas, and chemical industries to comply with U.S. Environmental Protection Agency’s (EPA) mandate to achieve smokeless flaring with a high CE. [ABSTRACT FROM AUTHOR]

Low-level laser therapy (LLLT) has been recognized as a light therapy that may be used for tissue regeneration, inflammation reduction, and pain relief. We intended to evaluate the effects of LLLT on the proliferation, migration, and tube formation of HUVECs as well as their related mechanisms. HUVECs were exposed to laser irradiation under different laser parameters (irradiation dose, interval and power intensity) in order to choose the optimal parameters, which were determined by the increase in proliferation of HUVECs as follows: irradiation dose of 4.0 J/m2, interval time of 12 h and 6 times in total. The HUVEC proliferation, migration, and tube formation, and levels of angiogenesis-related genes (HIF-1α, eNOS and VEGFA) were examined following LLLT. As suggested by the obtained data, LLLT (1.0, 2.0 and 4.0 J/m2) increased the HUVEC proliferation, migration, and tube formation in dose-and time-dependent manner, accompanied with increases in the levels of HIF-1α, eNOS, and VEGFA. Furthermore, the regulatory mechanism regarding the phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling pathway was explored, phosphorylation levels of PI3K and Akt proteins were assessed by Western blot assay, which showed the enhancement of phosphorylation of PI3K, Akt, and mTOR by LLLT. The inhibitor for the PI3K/Akt axis was used to verify the involvement of PI3K/Akt signaling pathway. The obtained results suggested that the inhibition of the PI3K/Akt signaling pathway attenuated the effects of LLLT on proliferation, migration, and angiogenesis of HUVECs. In conclusion, LLLT promotes the proliferation, migration, and angiogenesis of HUVECs via activation of the PI3K/Akt signaling pathway. • The promoting effect of LLLT on HUVEC proliferation is dose-dependent. • LLLT promotes the migration and tube-like structure formation of HUVECs. • LLLT activates PI3K/Akt signaling pathway to up-regulate HIF-1α, eNOS and VEGFA. • Disrupting PI3K/Akt signaling pathway weakens the biological functions of HUVECs. • The study uncovers the regulatory mechanism of LLLT on HUVECs. [ABSTRACT FROM AUTHOR]