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Gastrointestinal cancer (GIC), including gastric cancer and colorectal cancer, is a common malignant tumor originating from the gastrointestinal epithelium. Although the pathogenesis of GIC has not been fully elucidated, angiogenesis is recognized as the key pathological basis for the growth, invasion and metastasis of cancer cells, and GIC angiogenesis is closely related to vascular endothelial growth factor family, hypoxia-inducible factor family, fibroblast growth factor family and matrix metalloproteinase family. Recently, many natural products have shown a wide range of pharmacological biological activities against GIC. In this review, the effects and mechanisms of natural compounds on the angiogenesis of gastric and colorectal cancer were summarized. The results show that some natural compounds, especially gallic catechin gallate, astragaloside and curcumin, can effectively inhibit angiogenesis; the HIF-1α/VEGF, COX-2/PGE2, HGF/c-Met and PI3K/Akt/mTOR are involved in these inhibition effects. This review examines the anti-angiogenesis potential of natural products in the GIC treatment and provides clues to the development of vascular targeted agents.

The corona virus disease 2019 (COVID-19) global pandemic has had an unprecedented and persistent impact on oncological practice, especially for patients with lung cancer, who are more vulnerable to the virus than the normal population. Indeed, the onset, progression, and prognosis of the two diseases may in some cases influence each other, and inflammation is an important link between them. The original chronic inflammatory environment of lung cancer patients may increase the risk of infection with COVID-19 and exacerbate secondary damage. Meanwhile, the acute inflammation caused by COVID-19 may induce tumour progression or cause immune activation. In this article, from the perspective of the immune microenvironment, the pathophysiological changes in the lungs and whole body of these special patients will be summarised and analysed to explore the possible immunological storm, immunosuppression, and immune escape phenomenon caused by chronic inflammation complicated by acute inflammation. The effects of COVID-19 on immune cells, inflammatory factors, chemokines, and related target proteins in the immune microenvironment of tumours are also discussed, as well as the potential role of the COVID-19 vaccine and immune checkpoint inhibitors in this setting. Finally, we provide recommendations for the treatment of lung cancer combined with COVID-19 in this special group.

With the aging of the population and changes in lifestyle, the incidence of spine-related diseases is increasing, which has become a major global public health problem; this results in a huge economic burden on the family and society. Spinal diseases and complications can lead to loss of motor, sensory, and autonomic functions. Therefore, it is necessary to identify effective treatment strategies. Currently, the treatment of spine-related diseases includes conservative, surgical, and minimally invasive interventional therapies. However, these treatment methods have several drawbacks such as drug tolerance and dependence, adjacent spondylosis, secondary surgery, infection, nerve injury, dural rupture, nonunion, and pseudoarthrosis. Further, it is more challenging to promote the regeneration of the interstitial disc and restore its biomechanical properties. Therefore, clinicians urgently need to identify methods that can limit disease progression or cure diseases at the etiological level. Platelet-rich plasma (PRP), a platelet-rich form of plasma extracted from venous blood, is a blood-derived product. Alpha granules contain a large number of cytokines, such as platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), epidermal growth factor, platelet factor 4 (PF-4), insulin-like growth factor-1 (IGF-1), and transforming growth factor-β (TGF-β). These growth factors allow stem cell proliferation and angiogenesis, promote bone regeneration, improve the local microenvironment, and enhance tissue regeneration capacity and functional recovery. This review describes the application of PRP in the treatment of spine-related diseases and discusses the clinical application of PRP in spinal surgery.

Spinal cord injury (SCI) has considerable impact on patient physical, mental, and financial health. Secondary SCI is associated with inflammation, vascular destruction, and subsequent permanent damage to the nervous system. Mesenchymal stem cells (MSCs) have anti-inflammatory properties, promoting vascular regeneration and the release neuro-nutrients, and are a promising strategy for the treatment of SCI. Preclinical studies have shown that MSCs promote sensory and motor function recovery in rats. In clinical trials, MSCs have been reported to improve the American Spinal Injury Association (ASIA) sensory and motor scores. However, the effectiveness of MSCs in treating patients with SCI remains controversial. MSCs promote tumorigenesis and ensuring the survival of MSCs in the hostile environment of SCI is challenging. In this article we examine the evidence on the pathophysiological changes occurring after SCI. We then review the underlying mechanisms of MSCs in the treatment of SCI and summarize the potential application of MSCs in clinical practice. Finally, we highlight the challenges surrounding the use of MSCs in the treatment of SCI and discuss future applications.

Despite advances in cancer treatment, metastatic cancer is still the main cause of death in cancer patients. At present, the treatment of metastatic cancer is limited to palliative care. The abscopal effect is a rare phenomenon in which shrinkage of metastatic tumors occurs simultaneously with the shrinkage of a tumor receiving localized treatment, such as local radiotherapy or immunotherapy. Immunotherapy shows promise for cancer treatment, but it also leads to consequences such as low responsiveness and immune-related adverse events. As a promising target-based approach, intravenous or intratumoral injection of nanomaterials provides new opportunities for improving cancer immunotherapy. Chemically modified nanomaterials may be able to trigger the abscopal effect by regulating immune cells. This review discusses the use of nanomaterials in killing metastatic tumor cells through the regulation of immune cells and the prospects of such nanomaterials for clinical use.

Bone defects, which can be caused by factors such as trauma, tumor, or osteomyelitis, are clinically common. They lessen the weight a bone is able to bear and cause severe pain to the patient. Although bone transplantation is the gold standard for treating bone defects, it is not suitable for all patients due to its poor availability, risk of spreading disease, and possibility of requiring a secondary surgery. Bone cement as a filler for bone defects can fill any shape of bone defect, and can quickly solidify when injected, providing mechanical strength sufficient for supporting the normal physiological activities of the bone. However, traditional bone cement lacks the ability to induce bone regeneration. Recently, various methods for enhancing the bone regeneration ability of bone cement have been developed, such as adding bone morphogenetic proteins, mesenchymal stem cells, and inorganic substances to bone cement. These methods not only ensure the original biological properties of the bone cement, but also improve the bone cement in terms of its mechanical strength and ability to induce bone regeneration. The aim of this review is to overview the process of bone regeneration, introduce improved bone cement formulations designed to promote bone regeneration, and discuss the clinical application of bone cement and its possibilities for future improvement.

Intervertebral disc degeneration (IVDD) is a main cause of lower back pain, leading to psychological and economic burdens to patients. Physical therapy only delays pain in patients but cannot eliminate the cause of IVDD. Surgery is required when the patient cannot tolerate pain or has severe neurological symptoms. Although surgical resection of IVD or decompression of the laminae eliminates the diseased segment, it damages adjacent normal IVD. There is also a risk of re-protrusion after IVD removal. Cell therapy has played a crucial role in the development of regenerative medicine. Cell transplantation promotes regeneration of degenerative tissue. However, owing to the lack of vascular structure in IVD, sufficient nutrients cannot be provided for transplanted mesenchymal stem cells (MSCs). In addition, dead cells release harmful substances that aggravate IVDD. Extracellular vesicles (EVs) have been extensively studied as an emerging therapeutic approach. EVs generated by paracrine MSCs retain the potential of MSCs and serve as carriers to deliver their contents to target cells to regulate target cell activity. Owing to their double-layered membrane structure, EVs have a low immunogenicity and no immune rejection. Therefore, EVs are considered an emerging therapeutic modality in IVDD. However, they are limited by mass production and low loading rates. In this review, the structure of IVD and advantages of EVs are introduced, and the application of MSC-EVs in IVDD is discussed. The current limitations of EVs and future applications are described.

Spinal cord injury (SCI) causes tremendous harm to a patient’s physical, mental, and financial health. Moreover, recovery of SCI is affected by many factors, inflammation is one of the most important as it engulfs necrotic tissue and cells during the early stages of injury. However, excessive inflammation is not conducive to damage repair. Macrophages are classified into either blood-derived macrophages or resident microglia based on their origin, their effects on SCI being two-sided. Microglia first activate and recruit blood-derived macrophages at the site of injury—blood-borne macrophages being divided into pro-inflammatory M1 phenotypes and anti-inflammatory M2 phenotypes. Among them, M1 macrophages secrete inflammatory factors such as interleukin-β (IL-β), tumor necrosis factor-α (TNF-α), IL-6, and interferon-γ (IFN-γ) at the injury site, which aggravates SCIs. M2 macrophages secrete IL-4, IL-10, IL-13, and neurotrophic factors to inhibit the inflammatory response and inhibit neuronal apoptosis. Consequently, modulating phenotypic differentiation of macrophages appears to be a meaningful therapeutic target for the treatment of SCI. Biomaterials are widely used in regenerative medicine and tissue engineering due to their targeting and bio-histocompatibility. In this review, we describe the effects of biomaterials applied to modulate macrophage phenotypes on SCI recovery and provide an outlook.

Persulfate (PS) activated by Fe(ii) has been widely investigated for degradation of contaminants. However, the Fe(ii)/PS systems used for actual contaminated groundwater remediation have been restricted by circulation of Fe(iii)/Fe(ii). Herein, an ascorbic acid (AA) enhanced Fe(ii)/PS system was developed for degradation of tetracycline (TC) contaminated groundwater. The influence of Fe(ii), AA, PS dosage and pH on degradation of TC was investigated, the free radicals produced in the reaction were identified and the reusability of Fe(ii) in the Fe(ii)/PS/AA system for degradation of TC was also evaluated. The results showed that AA significantly promoted the degradation of TC in the Fe(ii)/PS system, and a degradation rate of 86% for TC was achieved at 60 min. The dominant oxidant species for contaminant degradation in the Fe(ii)/PS/AA system is ˙OH. Appropriate Fe(ii), AA and PS dosage can improve the degradation rate of TC. Moreover, the degradation rate of TC in the Fe(ii)/PS/AA system under acidic conditions is higher than that under alkaline conditions. With the increase of reaction time, TC can also be completely degraded even with a little Fe(ii) or under alkaline conditions in the Fe(ii)/PS/AA system, and Fe(ii) showed a good reusability for the degradation of TC. Thus, the AA-enhanced Fe(ii)/PS system for the degradation of contaminants displays the advantages of less Fe(ii) consumption and a wide range of pH. This method provides a new strategy for

We present a refinement framework to boost the performance of pre-trained semi-supervised video object segmentation (VOS) models. Our work is based on scale inconsistency, which is motivated by the observation that existing VOS models generate inconsistent predictions from input frames with different sizes. We use the scale inconsistency as a clue to devise a pixel-level attention module that aggregates the advantages of the predictions from different-size inputs. The scale inconsistency is also used to regularize the training based on a pixel-level variance measured by an uncertainty estimation. We further present a self-supervised online adaptation, tailored for test-time optimization, that bootstraps the predictions without ground-truth masks based on the scale inconsistency. Experiments on DAVIS 16 and DAVIS 17 datasets show that our framework can be generically applied to various VOS models and improve their performance.

The harmonic interaction analysis of delta-connected cascaded H-bridge (CHB) multilevel converter as shunt active power filter (APF) is helpful for design and control purposes. This paper presents a harmonic interaction analysis based on the derivation of a current and energy-based time-invariant state-space model with switching functions unknown beforehand. Based on that, we are capable to predict the harmonics propagation through the system and provide a precise calculation of various electrical quantities and switching functions that contain multiple frequency components with possible imbalances, giving an accurate reference for understanding, designing, and controlling of delta-connected CHB. The validity and accuracy of the harmonic interaction analysis are verified by the simulations of delta-connected CHB-based APF equipped with dc-link capacitors of reduced values.

Aim: Numerous studies have investigated the diagnostic role of long noncoding RNA HOX transcript antisense RNA in cancers, but its diagnostic efficacy is inconsistent. Methods: The PubMed, Embase, Web of Science and Cochrane Library databases are used to retrieve relevant studies. The bivariate effect model was used to compute the combined sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio and area under the receiver operating characteristic curve. Results: A total of 13 studies were included in this meta-analysis. The combined sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio and area under the receiver operating characteristic curve were: 0.77, 0.83, 4.7, 0.28, 17 and 0.87, respectively. Deeks’ funnel plot test (p = 0.103) indicated no publication bias. Conclusion: Long noncoding RNA HOX transcript antisense RNA may be a useful biomarker for cancer detection.

Spinal cord injury (SCI) is a severe and traumatic disorder that ultimately results in the loss of motor, sensory, and autonomic nervous function. After SCI, local immune inflammatory response persists and does not weaken or disappear. The interference of local adverse immune factors after SCI brings great challenges to the repair of SCI. Among them, microglia, macrophages, neutrophils, lymphocytes, astrocytes, and the release of various cytokines, as well as the destruction of the extracellular matrix are mainly involved in the imbalance of the immune microenvironment. Studies have shown that immune remodeling after SCI significantly affects the survival and differentiation of stem cells after transplantation and the prognosis of SCI. Recently, immunological reconstruction strategies based on biomaterials have been widely explored and achieved good results. In this review, we discuss the important factors leading to immune dysfunction after SCI, such as immune cells, cytokines, and the destruction of the extracellular matrix. Additionally, the immunomodulatory strategies based on biomaterials are summarized, and the clinical application prospects of these immune reconstructs are evaluated.

The behavior of nerve cells plays a crucial role in nerve regeneration. The mechanical, topographical, and electrical microenvironment surrounding nerve cells can activate cellular signaling pathways of mechanical transduction to affect the behavior of nerve cells. Recently, biological scaffolds with various physical properties have been developed as extracellular matrix to regulate the behavior conversion of nerve cell, such as neuronal neurite growth and directional differentiation of neural stem cells, providing a robust driving force for nerve regeneration. This review mainly focused on the biological basis of nerve cells in mechanical transduction. In addition, we also highlighted the effect of the physical cues, including stiffness, mechanical tension, two-dimensional terrain, and electrical conductivity, on neurite outgrowth and differentiation of neural stem cells and predicted their potential application in clinical nerve tissue engineering.

BACKGROUND It is well-known that severe acute pancreatitis (SAP) due to infection is mainly caused by intestinal bacterial translocation. The intestinal barrier is tasked with preventing intestinal pathogenic bacteria and toxins from reaching the parenteral tissues through the intestinal wall. Therefore, maintaining intestinal barrier function may be the key to preventing damage from acute pancreatitis (AP). The phosphatidylinositol 3-kinase/protein kinase B pathway (PI3K/PKB) plays a role in AP. However, the exact effect of PI3K/PKB on injury associated with SAP has not yet been found. OBJECTIVES The present study was aimed at investigating the impact of wortmannin (WT), a PI3K/PKB inhibitor, on intestinal barrier function in SAP rats. MATERIAL AND METHODS The rats were divided into 3 groups: 1) the Sham Surgery group (SS), whose duodenum and pancreas were flipped 3 times (n = 18); 2) the pancreatitis group (SAP), who were injected through retrograde pancreatic duct injection with 5% sodium taurocholate (n = 18); and 3) the WSAP intervention group (SAP+WT). Serum alpha-amylase levels, plasma endogenous endotoxin, hematoxylin-eosin (H&E) staining, intestinal mucosa electron microscopy, intestinal permeability, and expression of p-PKB (phosphorylated protein kinase B) were measured. RESULTS In our findings under an electron microscope, the SAP group presented cell edema and mitochondrial vacuolated degeneration, sparsely arranged microvilli, tight junction damage, and widening, while the WSAP group exhibited less change and lower pancreas scores (7.4 ±1.14, 10.2 ±1.48 and 12.0 ±1.58 for 3 h, 6 h and 12 h, respectively) (p < 0.05). Furthermore, the plasma endogenous endotoxin levels and Evans blue content of the WSAP group was significantly lower at all timepoints than in the SAP group (p < 0.05). Western blotting showed that p-PKB expression was lower in the WSAP group than in the SAP group (p < 0.05). Our study suggests that WT relieves intestinal permeability changes in SAP rats and may be dose-dependent. CONCLUSIONS The PI3K/PKB signal pathway may involve SAP-related intestinal injuries and WT may relieve SAP intestinal injuries through the PI3K/PKB pathway.

Green waste (GW), rich in cellulose and hemicellulose, is a valuable resource. Developing alternative sustainable technologies to utilize GW is attracting increasing attention. In this study, microwave hydrothermal carbonization (MHTC) process parameters including holding temperature, holding time, and liquid-to-solid ratio were optimized by a response surface design to tailor the properties of hydrochar. The hydrochar characteristic was mainly evaluated by the calorific value. The results showed that the highest hydrochar calorific value (∼23.01 MJ kg−1) could be observed at a holding temperature of 190 °C, a holding time of 1 h and liquid-to-solid ratio of 8:1. Correspondingly, the hydrochar yield ranged from 50.40% to 76.80%. The economic evaluation of hydrochar was also done in this work. These results show that the GW-derived hydrochar warrants further investigations as a fuel source and as an adsorbent material.

Anaerobic digestion (AD) is an effective way to improve the utilization of food waste (FW). Activated persulfate is a powerful oxidant. This research investigated the effect of activated persulfate on gas production from FW AD. Three activation methods including heating, lighting, and ultrasonication were used. The results showed that the addition of activated persulfate promoted gas production from FW AD. And the main biogas composition were CH4, CO2, and N2. The difference in SO42− concentration further verified the effect of activated methods on producing sulfate free radicals by heating, lighting and ultrasonication from persulfate. The activated persulfate enhanced gas production by improving the organic hydrolysis. Relatively, lighting and ultrasonication were better than heating in persulfate activation. At the same time, the accumulated gas volumes from ultrasonication (587 mL) and lighting (574 mL) were significantly higher than that in heating (478 mL). The environmental impact assessment and economic assessment suggests that the addition of activated persulfate in FW AD is beneficial because of the lower secondary pollution, lower cost and higher additional value.

Aim: To evaluate the prognostic role of mean corpuscular hemoglobin concentration (MCHC) in hepatocellular carcinoma (HCC) after hepatectomy. Patients & methods: A total of 289 HCC patients were classified into two groups based on the cut-off value of MCHC. Significant prognostic factors were screened by univariate and multivariate analysis. Results: Low MCHC value was significantly associated with tumor diameter (p = 0.004) and vascular invasion (p = 0.038). Besides, Cox regression analysis showed that low MCHC was significantly associated with poor prognostic outcomes with HCC after hepatectomy (overall survival: hazard ratio: 0.372; 95% CI: 0.206–0.672; p = 0.001; recurrence-free survival: hazard ratio: 0.450; 95% confidence interval: 0.317–0.638; p

BACKGROUND Inflammation and activation of the coagulation cascades have a role in the pathogenesis of malignancy, including hepatocellular carcinoma (HCC). This retrospective study aimed to investigate the prognostic role of the combined fibrinogen and neutrophil-to-lymphocyte ratio (F-NLR) in patients with resectable HCC. MATERIAL AND METHODS This retrospective study included 292 patients with HCC who underwent surgical resection. The receiver operating characteristic (ROC) curve was used to determine the cut-off value of preoperative fibrinogen (Fib) levels and the neutrophil-to-lymphocyte ratio (NLR). The. Hyperfibrinogenemia was >3.35 g/L, and an increased NLR was ≥2.47. The F-NLR was calculated for all patients. Kaplan-Meier survival curves, univariate analysis, multivariate analysis, and subgroup analysis were used to identify independent prognostic factors for overall survival (OS) and disease-free survival (DFS). The receiver operating characteristic (ROC) curve analysis of the F-NLR score and OS, according to the Barcelona Clinic Liver Cancer (BCLC) stage, was performed. RESULTS Increased F-NLR scores were significantly associated with the presence of tumor thrombus (P=0.001), larger tumor diameter (P

Increasing evidence shows microRNA-451 plays a crucial role in various tumors, but there is inconsistency. The aim of this study was to explore the prognostic role of miR-451 in various tumors.Online PubMed, EMBASE, Web of Science, and the Cochrane library database were searched through February 2019. Hazard ratios (HRs) were extracted and used to describe the association between expression of microRNA-451 and survival outcome, and the correlation between microRNA-451 and clinicopathologic features were described by pooled odds ratios (ORs).Sixteen retrospective studies containing 2122 patients were incorporated in this meta-analysis. High expression of miR-451 was considered statistically associated with prolonged overall survival (OS) (HR = 0.62, 95% CI 0.49-0.80, p 0.001) as well as RFS/DFS (HR = 0.55, 95% CI 0.42-0.71, p 0.001) compared with low expression of miR-451. Besides, the pooled ORs revealed significant association between high expression of miR-451 with lymph node invasion (yes vs. no) (OR = 0.64, 95% CI 0.46-0.90, P = 0.01), tumor diameter (big vs. small) (OR = 0.77, 95% CI 0.60-0.97, P = 0.028) and tumor stage (III + IV vs. I + II) (OR = 0.62, 95% CI 0.42-0.93, P = 0.019).MicroRNA-451 may serve as a promising clinical prognostic biomarker in various carcinomas.

An optimal strategy is presented to determine the combined control reference for the terminal and circulating currents of a shunt active power filter (APF) based on the delta-connected cascaded H-bridge (CHB) topology, hereby minimizing the operational power under ideal and non-ideal grid voltages, where the ideal grid voltages contain only the positive-sequence fundamental frequency component and the non-ideal grid voltages contain unbalance and/or harmonic components. The optimization is carried out to simultaneously satisfy the desired grid current distortion limits, the source current imbalance characteristics and the power factor as well as power balance requirement. By properly coordinating terminal current control and circulating current injection of the delta-connected CHB and taking possibly unbalanced and/or distorted grids the total power rating of the APF can be kept at minimum, leading to an economical operation. The optimization problem is formulated using a convex quadratic objective function and non-convex quadratic constraints and solved by an iterative procedure. The simulation results show that the proposed strategy is applicable and effective for reactive power and harmonic compensation with an optimal rating of the APF under ideal and non-ideal grid conditions.

Detecting climate events efficiently and accurately is important in traffic warning, disaster warning, and disease prevention. Given that ordinary event detection algorithms are ignored in climate domain's knowledge, the results of climate domain's event detection are not satisfactory. This paper proposes a climate event detection algorithm based on climate category word embedding(CEDCWE). This method combines the climate category word embedding and typical factors of climate events as a document representation model to express detailed information of climate documents and detect climate events efficiently and accurately. Compared with other methods, the CEDCWE algorithm can generate better climate document representations and climate event detection results. In the experiments, we acquire the datasets by a web crawler and evaluate our CEDCWE on real-world climate event detection tasks. Experimental results show that our CEDCWE is effective in climate document representation and outperforms typical methods.

This paper presents the application of a modular multilevel cascade converter(MMCC) based on single-delta bridge cells(SDBC) as an active power filter(APF). It is required that the mean value of the DC capacitor voltages is controlled so that the tracking of the source current reference is guaranteed in operation of APF. This paper proposes a DC capacitor voltage regulation method for MMCC-SDBC under different PCC voltages, including the ideal, distorted and unbalanced situations. With the application of the instantaneous symmetrical component theory, this paper analyzes the currents and average active power in three branches of MMCC-SDBC. Based on the analysis and the energy-power relationship of capacitors, the paper develops a systematic regulation method to maintain the DC-bus voltage on a fixed level. The simulation in MATLAB of a three-phase system under different PCC voltage conditions feeding a nonlinear load has shown the effectiveness of the proposed method.

This paper presents an optimal control strategy for load current compensation under different PCC voltages, including the ideal, distorted and unbalanced situations. This optimal strategy compromises the conflicting targets in the source currents, leading to a non-convex problem with convex quadratic cost function and non-convex quadratic constraints. To solve this non-convex quadratic constraints quadratic programming(QCQP) problem, by writing the constraints as a difference of two convex quadratic functions(DC), this paper introduces the sequential convex programming(SCP) algorithm based on the iterative method of the DC programming, in which the non-convex parts in the constraints are sequentially linearized. The fast convergence in a few iterations is illustrated to demonstrate the performance of the algorithm. The simulation in MATLAB of a three-phase system feeding a nonlinear load has shown the effectiveness and feasibility of the proposed compensation strategy.

This paper deals with the harmonic detection which is decoupled from the operation of active power filter. Kalman filter for harmonic detection based on a stochastic state-space model is proposed. However, it is a challenging task in large time varying system to know the process and noise covariance matrices Q and R. In this active power filter application, the current sensor TLC277CD and ADC LTC1403A which introduce load current measurement inaccuracies are analyzed to decide a rough R. Based on that R is exactly known, two adaptive Kalman filter algorithms to scale Q are proposed. One of the adaptive Kalman methods switches two basic Q matrices depending on the system in transient- or steady-state. The other Kalman algorithm tunes an optimal Q at each step by using the information of innovations sequence. The simulation results show that both adaptive Kalman filters have better dynamic performance than the regular Kalman filter.

STATic synchronous COMpensator (STATCOM) can be integrated into electric transmission systems to provide reactive power compensation and grid voltage support for achieving high-efficient and reliable Flexible AC Transmission Systems (FACTS). An emerging solution for STATCOM with modular structure and multilevel voltage output, named as modular multilevel STATCOM (mmSTATCOM) shows its great advantages of adaption to a wide voltage range, sinusoidal output voltages with less harmonics and less converter losses, compared with the traditional STATCOM. The cascaded Full-Bridge-based mmSTATCOM that is configured with three converter branches into a single delta connection can be classified into the modular multilevel cascade converter (MMCC) family and this configuration can be named as Single-Delta Full-Bridge (SDFB). This paper presents a novel integrated modeling method of SDFB-based STATCOM by taking the independent currents, the total energy and the internal energy balancing into consideration. Then a nonlinear multivariable state-space model is developed. Therefore, a nonlinear control method, named as nonlinear quadratic regulator (NQR), is accordingly proposed to guarantee a safe long-term operation of the SDFB-based STATCOM system both in the balanced and temporarily unbalanced grid conditions. The simulation results are followed to verify the system operations in the normal condition as well as during a temporary grid fault.