Functional Characterization of PmDXR, a Critical Rate-Limiting Enzyme, for Turpentine Biosynthesis in Masson Pine (Pinus massoniana Lamb.).

As one of the largest and most diverse classes of specialized metabolites in plants, terpenoids (oprenoid compounds, a type of bio-based material) are widely used in the fields of medicine and light chemical products. They are the most important secondary metabolites in coniferous species and play an important role in the defense system of conifers. Terpene synthesis can be promoted by regulating the expressions of terpene synthase genes, and the terpene biosynthesis pathway has basically been clarified in Pinus massoniana, in which there are multiple rate-limiting enzymes and the rate-limiting steps are difficult to determine, so the terpene synthase gene regulation mechanism has become a hot spot in research. Herein, we amplified a PmDXR gene (GenBank accession no. MK969119.1) of the MEP pathway (methyl-erythritol 4-phosphate) from Pinus massoniana. The DXR enzyme activity and chlorophyll a, chlorophyll b and carotenoid contents of overexpressed Arabidopsis showed positive regulation. The PmDXR gene promoter was a tissue-specific promoter and can respond to ABA, MeJA and GA stresses to drive the expression of the GUS reporter gene in N. benthamiana. The DXR enzyme was identified as a key rate-limiting enzyme in the MEP pathway and an effective target for terpene synthesis regulation in coniferous species, which can further lay the theoretical foundation for the molecularly assisted selection of high-yielding lipid germplasm of P. massoniana, as well as provide help in the pathogenesis of pine wood nematode disease.

Physical Grinding of Prefabricated Co3O4 and MCM-22 Zeolite for Fischer-Tropsch Synthesis: Impact of Pretreatment Procedure on the Dispersion and Catalytic Performance.

To improve the mess-specific activity of Co supported on zeolite catalysts in Fischer-Tropsch (FT) synthesis, the Co-MCM-22 catalyst was prepared by simply grinding the MCM-22 with nanosized Co3O4 prefabricated by the thermal decomposition of the Co(II)-glycine complex. It is found that this novel strategy is effective for improving the mess-specific activity of Co catalysts in FT synthesis compared to the impregnation method. Moreover, the ion exchange and calcination sequence of MCM-22 has a significant influence on the dispersion, particle size distribution, and reduction degree of Co. The Co-MCM-22 prepared by the physical grinding of prefabricated Co3O4 and H+-type MCM-22 without a further calcination process exhibits a moderate interaction between Co3O4 and MCM-22, which results in the higher reduction degree, higher dispersion, and higher mess-specific activity of Co. Thus, the newly developed method is more controllable and promising for the synthesis of metal-supported catalysts.

Cloning of PmMYB6 in Pinus massoniana and an Analysis of Its Function.

Phenylpropanoids are crucial for the growth and development of plants and their interaction with the environment. As key transcriptional regulators of plant growth and development, MYB-like transcription factors play a vital role in the biosynthesis of phenylpropanoid metabolites. In this study, we functionally characterized PmMYB6, a Pinus massoniana gene that encodes an R2R3-MYB transcription factor. It was confirmed by qPCR that PmMYB6 was highly expressed in the flowers, xylem, and phloem of P. massoniana. By overexpressing PmMYB6 in tobacco and poplar, we found that transgenic plants had enlarged xylem, increased content of lignin and flavonoids, and up-regulated expression of several enzyme genes of the phenylpropane metabolism pathway to different degrees. The above research results indicate that PmMYB6 is involved in the metabolic flux distribution of different branches of the phenylpropane metabolic pathway, and the results may provide clues for the regulation of metabolic fluxes between flavonoids and the lignin biosynthesis pathways of P. massoniana, as well as provide a basis for the molecular breeding of P. massoniana.

The Transcriptomic Analysis of the Response of Pinus massoniana to Drought Stress and a Functional Study on the ERF1 Transcription Factor.

Pinus massoniana is a major fast-growing timber tree species planted in arid areas of south China, which has a certain drought-resistant ability. However, severe drought and long-term water shortage limit its normal growth and development. Therefore, in this study, physiological indices, and the transcriptome sequencing and cloning of AP2/ERF transcription factor of P. massonsiana were determined to clarify its molecular mechanism of drought stress. The results showed that stomatal conductance (Gs) content was significantly decreased, and superoxide dismutase (SOD) activity, and malondialdehyde (MDA) and abscisic acid (ABA) content were significantly increased under drought stress. Transcriptomic analysis revealed that compared to the control, 9, 3550, and 4142 unigenes with differential expression were identified by comparing plants subjected to light, moderate or severe drought. AP2/ERF with high expression was screened out for cloning. To investigate the biological functions of ERF1, it was over-expressed in wild-type Populus davdianaand × P. bolleana via the leaf disc method. Under drought stress, compared to wild-type plants, ERF1 over-expressing poplar lines (OE) maintained a higher photosynthetic rate and growth, while the transpiration rate and stomatal conductance significantly decreased and water use efficiency was improved, indicating that drought tolerance was enhanced. This study provides an insight into the molecular mechanism of drought stress adaptation in P. massoniana.

Structure-directed linker optimization of novel HEPTs as non-nucleoside inhibitors of HIV-1 reverse transcriptase.

1-[(2-Hydroxyethoxy)methyl]-6-(phenylthio)thymines (HEPTs) have been previously described as an important class of HIV-1 nonnucleoside reverse transcriptase inhibitors (NNRTIs). In our continuously pursuing HEPT optimization efforts, a series of novel HEPTs, featuring -C(OH)CH2R, -CC, or -CHCH2R linker at the benzylic α-methylene unit, were developed as NNRTIs. Among these new HEPTs, the compound C20 with -CHCH3 group at the benzylic α-methylene unit conferred the highest potency toward WT HIV-1 and selectivity (EC50 = 0.23 µM, SI = 150.20), which was better than the lead compound HEPT (EC50 = 7 µM, SI = 106). Also, C20 was endowed with high efficacy against clinically relevant mutant strains (EC50(L100I) = 1.07 µM; EC50(K103N) = 4.33 µM; EC50(Y181C) = 5.57 µM; EC50(E138K) = 1.06 µM; EC50(F227L+V106A) = 5.45 µM) and wild-type HIV-1 reverse transcriptase (RT) with an IC50 value of 0.55 µM. Molecular docking and molecular dynamics simulations, as well as preliminary structure-activity relationship (SAR) analysis of these new compounds, provided a deeper insight into the key structural features of the interactions between HEPT analogs and HIV-1 RT and laid the foundation for further modification on HEPT scaffold.

Development of novel S-N3-DABO derivatives as potent non-nucleoside reverse transcriptase inhibitors with improved potency and selectivity.

Following on our initial discovery of S-CN-DABOs as non-nucleoside reverse transcriptase inhibitors (NNRTIs), a series of novel S-N3-DABO derivatives F1-F31 were developed by substituting the cyano group of S-CN-DABOs with azide group. Some of these compounds were conferred significantly increased potency against wild-type HIV-1 and clinically observed mutant strains. Remarkably, the best compound F10 exerted a 7-fold improvement in potency (EC50 = 0.053 µM) and 12.5-fold higher selectivity (SI = 6818) in MT-4 cells infected with wild-type HIV-1, compared to that of the parent compound B1 (EC50 = 370 nM, SI = 547). The anti-HIV-1 activity of F10 against the tested mutant strains was prominently enhanced. For wild-type reverse transcriptase, it was approximately 19-fold more potent (IC50 = 0.080 µM) than B1 (IC50 = 1.51 µM). It was not found that this analog had significant inhibition of hERG, CYP, and acute toxicity after a single dose of F10 (1.0 g/kg).

Effectiveness of exercise in reducing cerebral stroke risk factors: A systematic review and meta-analysis.

OBJECTIVES: This study aimed to explore the relationship between exercise and cerebral stroke and provide evidence for the prevention of cerebral stroke. MATERIALS/METHODS: All clinical trials of exercise intervention for atherosclerosis were systematically reviewed. Five major databases were searched to retrieve relevant studies from their inception to May 2022. According to the magnitude of heterogeneity, the random and fixed-effect models were used to test reasonably. RESULTS: According to the inclusion and exclusion criteria, 1341 articles were screened and 13 articles involving 825 patients were identified. The result showed that in the randomized controlled trials carotid intima-media thickness index was lower in the exercise group (-0.04 mm, 95% confidence interval: -0.07 to -0.01). All were statistically significant (P < .005) and subgroup analysis showed that the intervention period and paper quality are sources of heterogeneity. CONCLUSIONS: The results of this systematic review suggest that exercise is associated with a slow increase in carotid intima-media thickness, which may provide evidence that exercise helps reduce cerebral stroke.

Structure-Based design of [(2-Hydroxyethoxy)methyl]-6-(phenylthio)-thymine derivatives as nonnucleoside HIV-1 reverse transcriptase Inhibitors: From HEPTs to Sulfinyl-substituted HEPTs.

The [(2-hydroxyethoxy)methyl]-6-(phenylthio)thymine (HEPT) analogs were reported to be a kind of promising lead compounds as nonnucleoside HIV-1 reverse transcriptase inhibitors. In this work, a series of novel sulfinyl-substituted analogs were designed by structure-based design strategy with the purpose of improving the activity of HEPT, followed by evaluating their anti-HIV-1 activity in MT-4 cells. Most of the final compounds had moderate to strong activity against wild-type HIV-1 strain (IIIB) with EC50 values in the range of 0.21-1.91 µM, which were around 4 âˆ¼ 32-fold better than the reference compound HEPT. Some of them showed higher sensitivity toward clinically relevant mutant L100I and E138K viruses than NVP. Selected compounds were further evaluated for their activity against wild-type reverse transcriptase (RT), and most of them exhibited nanomolar activity, suggesting a good correlation with the cell-based activity. The compounds 11h, 11l, and 11ab displayed the best anti-HIV-1 activity against wild-type HIV-1 strain (EC50 = 0.280, 0.209, and 0.290 µM) and nanomolar activity against mutant strains (L100I and E138K), superior to HEPT and NVP. Molecular modeling studies were also performed to elucidate the biological activity, providing a structural insight for follow-up research on HEPT optimization.

Expansion of the S-CN-DABO scaffold to exploit the impact on inhibitory activities against the non-nucleoside HIV-1 reverse transcriptase.

The α-cyanoarylmethyl-3, 4-dihydropyrimidin-4(3H)-ones (S-CN-DABOs) were reported as a kind of reverse transcriptase inhibitors of human immunodeficiency virus type-1 (HIV-1) by our group in 2007. In this paper, we proposed to expand the S-CN-DABO scaffold to enrich the structure-activity relationship (SAR) of the phenyl ring that was predicted to be located in the W229 hydrophobic pocket. Thirty-nine S-CN-DABO derivatives were manufactured to explore the impact on inhibitory activities against the non-nucleoside HIV-1 reverse transcriptase. These analogues displayed up to low nanomolar activity against wild-type (WT) HIV-1 and good activity against several clinically relevant resistant mutant viruses, especially rilpivirine-associated resistant mutant E138K strain. The inhibitory ability toward the RT enzyme was significantly improved. Compound B23 with a 2, 6-difluoro-phenyl group showed inhibitory effects with an EC50 value of 20.8 nM against HIV-1 WT strain, and an EC50 of 50 nM targeting mutant E138K, which were about 20-fold better than the lead compound B1. Molecular docking analysis elucidated the biological activity and offered a structural insight for follow-up research. In addition, compound B23 also showed favorable drug-like properties in vitro and in vivo. There was no significant inhibition of hERG (IC50 > 40 µM), no apparent CYP enzymatic inhibitory activity and acute toxicity in mouse models. Perfect oral bioavailability of compound B23 was revealed (F = 164%, SD rats). In summary, these S-CN-DABOs compounds could be further optimized and modified for promising drug candidates in anti-HIV clinical therapy.

Synthesis of hierarchical nanocrystalline ß zeolite as efficient catalyst for alkylation of benzene with benzyl alcohol.

To develop an efficient solid acid catalysts for the Friedel-Crafts alkylation reaction, especially for involving bulky molecules, the direct synthesis of hierarchical nanocrystalline ß zeolites were achieved by using amphiphilic organosilane ([(CH3O)3SiC3H6N(CH3)2C18H37]Cl, TPOAC) as collaborative structure-directing agent (SDA). The growth evolution of ß crystals and the influence of TPOAC/SiO2 molar ratio on the mesoporous structure, crystal size, and acidic properties of ß zeolites were investigated and discussed in detail. The characterization results reveal that intracrystalline mesopores and intercrystalline mesopores/macropores via the stacking of ß nanocrystals were generated over the hierarchical ß zeolites. Moreover, most of the strong acid sites were well remained compared with the conventional microporous ß zeolite. Consequently, the hierarchical nanocrystalline ß zeolite synthesized under the optimized synthesis conditions shows improved specific catalytic activity of acid sites (turnover number, TON) in alkylation of benzene with benzyl alcohol, which can be attributed to the integrated balance of considerable mesoporosity, accessibility of the acid sites, and well-remained strong acid sites in the hierarchical ß zeolite.

Characterization and Interaction Analysis of the Secondary Cell Wall Synthesis-Related Transcription Factor PmMYB7 in Pinus massoniana Lamb.

In vascular plants, the importance of R2R3-myeloblastosis (R2R3-MYB) transcription factors (TFs) in the formation of secondary cell walls (SCWs) has long been a controversial topic due to the lack of empirical evidence of an association between TFs and downstream target genes. Here, we found that the transcription factor PmMYB7, which belongs to the R2R3-MYB subfamily, is involved in lignin biosynthesis in Pinus massoniana. PmMYB7 was highly expressed in lignified tissues and upon abiotic stress. As a bait carrier, the PmMYB7 protein had no toxicity or autoactivation in the nucleus. Forty-seven proteins were screened from the P. massoniana yeast library. These proteins were predicted to be mainly involved in resistance, abiotic stress, cell wall biosynthesis, and cell development. We found that the PmMYB7 protein interacted with caffeoyl CoA 3-O-methyltransferase-2 (PmCCoAOMT2)-which is involved in lignin biosynthesis-but not with beta-1, 2-xylosyltransferase (PmXYXT1) yeast two-hybrid (Y2H) studies. Our in vivo coimmunoprecipitation (Co-IP) assay further showed that the PmMYB7 and PmCCoAOMT2 proteins could interact. Therefore, we concluded that PmMYB7 is an upstream TF that can interact with PmCCoAOMT2 in plant cells. These findings lay a foundation for further research on the function of PmMYB7, lignin biosynthesis and molecular breeding in P. massoniana.

Controlled direct synthesis of single- to multiple-layer MWW zeolite.

The minimized diffusion limitation and completely exposed strong acid sites of the ultrathin zeolites make it an industrially important catalyst especially for converting bulky molecules. However, the structure-controlled and large-scale synthesis of the material is still a challenge. In this work, the direct synthesis of the single-layer MWW zeolite was demonstrated by using hexamethyleneimine and amphiphilic organosilane as structure-directing agents. Characterization results confirmed the formation of the single-layer MWW zeolite with high crystallinity and excellent thermal/hydrothermal stability. The formation mechanism was rigorously revealed as the balanced rates between the nucleation/growth of the MWW nanocrystals and the incorporation of the organosilane into the MWW unit cell, which is further supported by the formation of MWW nanosheets with tunable thickness via simply changing synthesis conditions. The commercially available reagents, well-controlled structure and the high catalytic stability for the alkylation of benzene with 1-dodecene make it an industrially important catalyst.

Serum NSE and S100B protein levels for evaluating the impaired consciousness in patients with acute carbon monoxide poisoning.

ABSTRACT: The aim of this study was to investigate the associations between the levels of neuron-specific enolase (NSE) and S100B protein and coma duration, and evaluate the optimal cut-off values for prediction coma duration ≥ 72 hours in patients with acute carbon monoxide poisoning (ACOP).A total of 60 patients with ACOP were divided into 3 following groups according to their status of consciousness and coma duration at admission: Awake group [Glasgow Coma Scale score (GCS score) ≥ 13 points], Coma < 72 hours group (GCS score < 13 points and coma duration < 72 h), and Coma ≥ 72 hours group (GCS score < 13 points and coma duration ≥ 72 h). The levels of serum NSE and S100B protein were measured after admission.There were significant differences in GCS score, carbon monoxide (CO) exposure time, NSE, and S100B levels between the Coma ≥ 72 h group and the Awake group, and between the Coma < 72 h group and the Awake group. Significant differences in GCS score, NSE, and S100B levels were also found between Coma ≥ 72 h group and Coma < 72 h group. Correlation analysis showed that NSE and S100B were positively correlated (rs = 0.590, P < .01); NSE and S100B were negatively correlated with GCS score (rs = -0.583, rs = -0.590, respectively, both P < .01). The areas under the curve (AUCs) of NSE, S100B, and GCS score to predict the coma duration ≥ 72 hours were 0.754, 0.791, and 0.785, respectively. Pairwise comparisons did not show differences among the 3 groups (all P > .05). The sensitivity and specificity of NSE prediction with a cut-off value of 13 µg/L were 80% and 64%, respectively, and those of S100B prediction with a cut-off value of 0.43 µg/L were 70% and 88%, respectively.The NSE and S100B protein levels were significantly correlated with the degree of impaired consciousness and had the same clinical value in predicting coma duration of ≥ 72 hours in patients with ACOP.

Transcriptome-Wide Identification of WRKY Transcription Factors and Their Expression Profiles under Different Types of Biological and Abiotic Stress in Pinus massoniana Lamb.

Pinus massoniana Lamb, an economically important conifer tree, is widely distributed in China. WRKY transcription factors (TFs) play important roles in plant growth and development, biological and abiotic stress. Nevertheless, there is little information about the WRKY genes in P. massoniana. By searching for conserved WRKY motifs in transcriptomic RNA sequencing data for P. massoniana, 31 sequences were identified as WRKY TFs. Then, phylogenetic and conserved motif analyses of the WRKY family in P. massoniana, Pinus taeda and Arabidopsis thaliana were used to classify WRKY genes. The expression patterns of six PmWRKY genes from different groups were determined using real-time quantitative PCR for 2-year-old P. massoniana seedings grown in their natural environment and challenged by phytohormones (salicylic acid, methyl jasmonate, or ethephon), abiotic stress (H2O2) and mechanical damage stress. As a result, the 31 PmWRKY genes identified were divided into three major groups and several subgroups based on structural and phylogenetic features. PmWRKY genes are regulated in response to abiotic stress and phytohormone treatment and may participate in signaling to improve plant stress resistance. Some PmWRKY genes behaved as predicted based on their homology with A. thaliana WRKY genes, but others showed divergent behavior. This systematic analysis lays the foundation for further identification of WRKY gene functions to aid further exploration of the functions and regulatory mechanisms of PmWRKY genes in biological and abiotic stress in P. massoniana.

Cardiac contractility modulation attenuates structural and electrical remodeling in a chronic heart failure rabbit model.

BACKGROUND: Cardiac contractility modulation (CCM) is non-excitatory electrical stimulation for improving cardiac function. This study aimed to evaluate the effects of CCM on structural and electrical remodeling in a rabbit model of chronic heart failure (CHF). METHODS: Thirty rabbits were randomly divided into the sham, CHF, and CCM groups. The CHF model was induced 12 weeks after trans-aortic constriction by pressure unloading and CCM was delivered to the myocardium for 4 weeks. Corrected QT intervals, the ventricular effective refractory period, and inducibility of ventricular tachycardia were measured by an electrophysiological examination. Connective tissue growth factor, galectin-3, Kv4.3, KCNQ1, KCNH2, and connexin 43 protein levels were measured by western blotting. RESULTS: The CHF group had a significantly prolonged corrected QT interval and ventricular effective refractory period, and increased inducibility of ventricular tachycardia. Prominent myocardial fibrosis and increased hydroxyproline content were observed in the CHF group, but these were suppressed in the CCM group. Kv4.3, KCNQ1, KCNH2, and connexin 43 protein levels were significantly lower in the CHF group, but treatment with CCM partially restored their levels. CONCLUSIONS: CCM attenuates myocardial structural and electrical remodeling during CHF. These findings provide evidence for clinical use of CCM in treating CHF.

Chondroma in the Area of the Spheno-Ethmoid Junction.

Chondroma in the area of the spheno-ethmoidal junction is very rare. A 29-year-old male patient with chronic rhinosinusitis with nasal polyps was arranged for a preoperative computed tomography scan, and a lesion was accidentally found in his spheno-ethmoidal junction and involved the skull base. Combined with MRI, the lesion was misdiagnosed as fungal sinusitis. However, no fungal lesions were found during the operation, and cartilage tissue was confirmed only after some bone was ground away under the guidance of a surgical navigation system. Our case indicates that chondroma is easily misdiagnosed as fungal sinusitis when it appears in the sinuses and should be carefully distinguished from fungal sinusitis. Moreover, when lesions involve the skull base, surgical navigation systems are useful in accurately locating lesions.

Cardiac Contractility Modulation Attenuates Chronic Heart Failure in a Rabbit Model via the PI3K/AKT Pathway.

The Akt plays an important role in regulating cardiac growth, myocardial angiogenesis, and cell death in cardiac myocytes. However, there are few studies to focus on the responses of the Akt pathway to cardiac contractility modulation (CCM) in a chronic heart failure (HF) model. In this study, the effects of CCM on the treatment of HF in a rabbit model were investigated. Thirty six-month-old rabbits were randomly separated into control, HF, and CCM groups. The rabbits in HF and CCM groups were pressure uploaded, which can cause an aortic constriction. Then, CCM was gradually injected to the myocardium of rabbits in the CCM group, and this process lasted for four weeks with six hours per day. Rabbit body weight, heart weight, and heart beating rates were recorded during the experiment. To assess the CCM impacts, rabbit myocardial histology was examined as well. Additionally, western blot analysis was employed to measure the protein levels of Akt, FOXO3, Beclin, Pi3k, mTOR, GSK-3ß, and TORC2 in the myocardial histology of rabbits. Results showed that the body and heart weight of rabbits decreased significantly after suffering HF when compared with those in the control group. However, they gradually recovered after CCM application. The CCM significantly decreased collagen volume fraction in myocardial histology of HF rabbits, indicating that CCM therapy attenuated myocardial fibrosis and collagen deposition. The levels of Akt, FOXO3, Beclin, mTOR, GSK-3ß, and TORC2 were significantly downregulated, but Pi3k concentration was greatly upregulated after CCM utilization. Based on these findings, it was concluded that CCM could elicit positive effects on HF therapy, which was potentially due to the variation in the Pi3k/Akt signaling pathway.

Synergistic conversion of coal char and methane for syngas and carbon-based supercapacitor electrodes.

A facile one-pot process for synergistic conversion of coal char and methane is conducted by employing K2CO3 as the catalyst. Besides syngas production, valuable carbon products are obtained and used to serve for supercapacitor electrodes. Effect of the operating parameters (including the catalyst dosage, gas feed flow rate, reaction temperature and time) is evaluated on electrochemical performance of the as-prepared carbon. The appropriate surface and structural properties enable the prepared carbon electrode to have a remarkable capacitive performance, along with a specific capacitance up to 125 F/g at a scan rate of 5 mV/s and 133 F/g at a current density of 1 A/g. According to the potential capacitive contribution of the carbon species, the high capacitive performance is mainly attributed to formation and growth of abundant carbon fibers in the one-pot process.

miRNA-103 promotes chondrocyte apoptosis by down-regulation of Sphingosine kinase-1 and ameliorates PI3K/AKT pathway in osteoarthritis.

OBJECTIVES: The aim of the present study was to determine the effects of miRNA-103 on chondrocyte apoptosis and molecular mechanisms in osteoarthritis (OA) progression. METHODS: The cell proliferation, apoptosis, and recovery ability were measured by cell counting kit-8 (CCK-8), flow cytometry, and wound healing assays. The interaction of miRNA-103 and Sphingosine kinase-1 (SPHK1) were determined by using luciferase reporter assay. The expression of mRNA and proteins were measured by qRT-PCR and Western blot. OA rat model was established by surgery stimulation. RESULTS: miRNA-103 expression was significantly increased in the cartilage of OA patients and surgery-induced OA rat models. miRNA-103 transfection into primary rat chondrocytes reduced SPHK1 expression, induced apoptosis, inhibited cell proliferation, and impeded scratch assay wound closure. Moreover, expression of total AKT, and p-AKT were significantly reduced in miRNA-103-overexpressing chondrocytes while SPHK1 up-regulation increased the expression of phosphatidylinsitol-3-kinase (PI3K) and p-AKT, and reversed the proliferation suppression induced by the miRNA-103 mimic. CONCLUSIONS: Our studies suggest that miRNA-103 contributes to chondrocyte apoptosis, promoting OA progression by down-regulation of PI3K/AKT pathway through the reduction in SPHK1 activity.

Optical coherence tomography guided successful treatment without stent implantation in a patient with non-ST-segment elevation myocardial infarction caused by plaque rapture: A case report.

RATIONALE: Primary percutaneous coronary intervention (PPCI) with immediate stenting provides effective revascularization. While the risks of no-reflow, stent thrombosis, stent undersizing, and malapposition reduced the benefits in patients with high burden thrombosis. Intravascular imaging, especially optical coherence tomography (OCT), offers potential in optimization of percutaneous coronary intervention. PATIENT CONCERNS: A 51-year-old male underwent coronary angiography (CAG) due to chest pain with minimal ST-segment depression of the electrocardiogram. DIAGNOSES: Urgent CAG revealed burden thrombus in the mid left anterior descending coronary artery (LAD) with TIMI grade I distal flow. INTERVENTIONS: After aspiration thrombectomy, OCT was used to evaluate the target lesion of non-ST-segment elevation myocardial infarction (NSTEMI) and conservative treatment without stent implantation was selected. OUTCOMES: CAG repeated 1 month after PPCI revealed TIMI grade III blood flow in LAD and only minimal stenosis in the target lesion. OCT showed a cavity formation due to plaque rupture and MLA increased after thrombus dissolution. Follow-up was uneventful at 6 months. LESSONS: OCT may be useful imaging modality to identify the characteristic of culprit lesion of acute myocardial infarction and subsequently guide individual treatment.