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Cesium-based inorganic perovskites have emerged as promising light-harvesting materials for perovskite solar cells (PSCs) due to their promising thermal- and photo-stability. However, obstacles to commercialization remain regarding their phase instability. In this work, we report a facile and effective strategy to regulate the surface compressive strain via in-situ surface reaction to stabilize CsPbI3 perovskite. The use of a chelating ligand with a molecular configuration closely matching the integer multiples of the unit cell lattice parameters of CsPbI3 induces compressive strain at the surface of CsPbI3. The chemical bonding and strain modulation synergistically not only passivate film defects, but also inhibit perovskite phase degradation, thus significantly improving the intrinsic stability of inorganic perovskite. Consequently, enhanced power conversion efficiency (PCE) of 21.0% and 18.6% were respectively achieved in 0.16-cm2 lab-scale devices and 25.3-cm2 solar modules. Further, surface reaction enables PSCs with enhanced thermal and operational stability; these devices retain over 95% of their initial PCE after damp-heat tests (i.e., in 85 ℃ and 85% R.H. air) for 2000 h, and remain 99% of their initial PCE after operating for 2000 h, representing one of the most stable inorganic PSCs reported so far.

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Recent research indicated that ulcers and peripheral vascular disease resulting from drug-resistant bacterial infections are the main causes of delayed healing in chronic diabetic wounds. 5-Aminolevulinic acid (ALA) is a second-generation endogenous photosensitizer. The therapeutic effect and mechanism of ALA-mediated photodynamic therapy (ALA-PDT) on methicillin-resistant Staphylococcus aureus (MRSA)-infected wounds in diabetic rats were investigated in this study. The results revealed the promising antibacterial effects of ALA-PDT MRSA in vitro, with a minimum inhibitory concentration and minimum bactericidal concentration of 250 and 500 µM, respectively. ALA-PDT also changed the permeability and structural integrity of bacterial cell membranes by producing reactive oxygen species. Meanwhile, ALA-PDT accelerated wound healing in MRSA-infected diabetic rats, with 5 % ALA-PDT achieving complete sterilization in 14 days and wound closure in 21 days. Treatment with 5 % ALA-PDT additionally improved the histopathological appearance of skin tissue, as well as fibrosis, inflammatory cytokine release, and angiogenesis-related protein expression. These findings indicated that ALA-PDT significantly promoted the healing of MRSA-infected wounds in diabetic rats by eliminating bacteria, inhibiting inflammation, generating granulation tissues, promoting neovascularization, and restoring damaged nerves. In addition, the healing mechanism was related to the activation of inflammatory and angiogenesis pathways through the regulation of tumor necrosis factor-alpha and interleukin-6 expression and upregulation of CD206, CD31, and VEGF. These findings underscored the potential role of ALA-PDT in promoting the healing of chronic diabetic wounds.

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The ever-increasing power conversion efficiency of perovskite solar cells has illuminated the future of the photovoltaic industry, but the development of commercial devices is hampered by their poor stability. In this study, we report a scalable stabilization method using vapor-phase fluoride treatment, which achieves 18.1%-efficient solar modules (228 square centimeters) with accelerated aging-projected T80 lifetimes (time to 80% of efficiency remaining) of 43,000 ± 9000 hours under 1-sun illumination at 30°C. The high stability results from vapor-enabled homogeneous fluorine passivation over large-area perovskite surfaces, suppressing defect formation energy and ion diffusion. The extracted degradation activation energy of 0.61 electron volts for solar modules is comparable to that of most reported stable cells, which indicates that modules are not inherently less stable than cells and closes the cell-to-module stability gap.

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LD4, a novel porphyrin derivative, has attracted much attention for its excellent anti-inflammatory properties. It can promote the healing of colonic mucosa, reduce inflammatory response, regulate oxidative stress, and thus improve ulcerative colitis (UC) symptoms. However, the specific signaling pathways of LD4-PDT involved in UC have not been explored. The present study aimed to elucidate the effects of LD4 on UC and to investigate the underlying mechanisms both in vivo and in vitro. We classified and screened the LD4-PDT proteomic data to obtain key targets. Proteomic data revealed that EPHX2 and STAT3 are key targets of LD4-PDT for UC. Moreover, transcription factor STAT3 positively regulates the expression of EPHX2. Inhibiting EPHX2 can prevent the activation of NF-κB signaling pathway. Next, through pharmacological inhibition experiments, we confirmed that LD4-PDT can reduce intestinal inflammation by inhibiting STAT3-EPHX2 axis. However, by treating normal intestinal epithelial cells and colon cancer cells with TPPU and Stattic, our data confirmed that the STAT3-EPHX2 axis does not exist in colon cancer. In this study, we demonstrated that the transcription factor STAT3 can positively regulate the expression of EPHX2 in normal colon. LD4 can alleviate UC by inhibiting the STAT3-EPHX2 axis, but this axis does not exist in colon cancer. LD4-PDT may become a new and effective method for treating UC.

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Globally, prostate cancer is the most commonly diagnosed tumor and a cause of death in older men. Abiraterone, an orally administered irreversible CYP17 inhibitor, is employed to treat prostate cancer. However, abiraterone has several clinical limitations, such as poor water solubility, low dissolution rate, low bioavailability, and toxic side effects in the liver and kidney. Therefore, there is a need to identify high-efficiency and low-toxicity water-soluble abiraterone derivatives. In this work, we aimed to design and synthesize a series of abiraterone derivatives by methoxypoly(ethylene glycol) (mPEG) modification. Their antitumor activities and toxicology were analyzed in vitro and in vivo. The most potent compound, 2e, retained the principle of action on the CYP17 enzyme target and significantly improved the abiraterone water solubility, cell permeability, and blood safety. No significant abnormalities were observed in toxicology. mPEG-modification significantly improved abiraterone's antitumor activity and efficiency while reducing the associated toxic effects. The finding will provide a theoretical basis for future clinical application of mPEG-modified abiraterone.

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Klebsiella pneumoniae is a Gram-negative bacterium that induces acute lung injury (ALI) and inflammation in humans, necessitating immediate hospitalization and treatment. At present, the clinical treatment is largely dependent on hormones or antibiotics but is associated with drawbacks posed by the lack of eradication of the bacterium upon treatment and drug resistance. Therefore, there is an urgent need for novel and effective treatments. The current study investigated the treatment of K. pneumonia-induced ALI using a photosensitizer LD4 in conjunction with photodynamic therapy (PDT). The water content in the lungs (corresponding to edema) of a rat model of pneumonia induced by K. pneumoniae was reduced upon treatment with LD4-PDT. The counts of leukocyte, lymphocyte, and polymorphonuclear leukocyte in the blood were determined in the rat model of pneumonia, as were the concentrations of inflammatory cytokines (estimated using an enzyme-linked immunosorbent assay). The LD4-PDT treatment prominently reduced the levels of interleukin (IL)-6, IL-10, tumor necrosis factor-α, superoxide dismutase, and immune cells. Results suggest that LD4-PDT considerably alleviates the inflammation and oxidative stress caused by K. pneumoniae in the rat model of pneumonia. Furthermore, it could effectively improve the survival rate in the rat model of K. pneumonia-induced pneumonia and ameliorate histological changes while protecting the integrity of the pulmonary epithelial cells. These results highlight the potential application of LD4 as a photosensitizer for treating acute pneumonia induced by K. pneumoniae.

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BACKGROUND: Breast cancer (BC) is the most common cancer among women worldwide and a leading cause of cancer-associated deaths among women. However, there is a lack of accurate prognostic biomarkers for BC. In the present study, we aimed to identify a genomic instability (GI)-associated microRNA signature as a novel potential prognostic biomarker in BC. METHODS: We performed an integrative analysis to investigate the relationship between GI and BC and identify GI-associated microRNAs (miRNAs). Subsequently, we conducted a discovery and validation study using multicenter cohorts. The GI-associated miRNA signature was developed in the discovery cohort and independently validated in internal and external cohorts. RESULTS: GI-associated miRNAs expression in BC showed heterogeneity and was significantly correlated with BC prognosis. We identified a GI-associated two-miRNA signature (miR-105-5p and miR-767-5p), termed GI2miR, that stratified BC patients into high-risk and low-risk groups with significantly different clinical outcomes (log-rank p = 0.027) in The Cancer Genome Atlas (TCGA) discovery cohort (n = 763). The prognostic value of GI2miR was further validated in internal TCGA validation cohort (n = 253) (log-rank p = 0.035) and independent GSE22216 cohort (n = 210) (log-rank p = 0.036). The GI2miR demonstrated independent prognostic value in multivariate Cox proportional hazard regression analyses and stratification analysis. CONCLUSIONS: We have developed a novel prognostic signature based on GI-associated two miRNAs for BC, which may lay the foundation for BC to improve prognosis prediction.

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Poly(nickel-benzene-1,2,4,5-tetrakis(thiolate)) (Ni-btt), an organometallic coordination polymer (OMCP) characterized by the coordination between benzene-1,2,4,5-tetrakis(thiolate) (btt) and Ni2+ ions, has been recognized as a promising p-type thermoelectric material. In this study, we employed a constitutional isomer based on benzene-1,2,3,4-tetrakis(thiolate) (ibtt) to generate the corresponding isomeric polymer, poly(nickel-benzene-1,2,3,4-tetrakis(thiolate)) (Ni-ibtt). Comparative analysis of Ni-ibtt and Ni-btt reveals several common infrared (IR) and Raman features attributed to their similar square-planar nickel-sulfur (Ni-S) coordination. Nevertheless, these two polymer isomers exhibit substantially different backbone geometries. Ni-btt possesses a linear backbone, whereas Ni-ibtt exhibits a more undulating, zig-zag-like structure. Consequently, Ni-ibtt demonstrates slightly higher solubility and an increased bandgap in comparison to Ni-btt. The most noteworthy dissimilarity, however, manifests in their thermoelectric properties. While Ni-btt exhibits p-type behavior, Ni-ibtt demonstrates n-type carrier characteristics. This intriguing divergence prompted further investigation into the influence of OMCP backbone geometry on the electronic structure and, particularly, the thermoelectric properties of these materials.

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BACKGROUND: Pseudomonas aeruginosa is a gram-negative bacterium without spores, and it is one of the pathogens that easily cause secondary infectious diseases when human immune function is low. The purpose of this study is to explore the inhibitory effect of photodynamic antibacterial chemotherapy-induced by cationic porphyrin derivative on clinical P. aeruginosa and its mechanism. METHODS: The uptake of photosensitizer by P. aeruginosa and L929 cells was measured by an ultraviolet spectrophotometer. Effect of laser energy density on the bacterial activity of P. aeruginosa and post antibiotic effect were measured by bacterial suspension and tenfold dilution method. Flow cytometry and scanning electron microscopy were used to observe the activity and morphological changes of P. aeruginosa after PACT treatment. RESULTS: The uptake of Tetra-ATPP-Lys-by P. aeruginosa and L929 was shown as concentration-dependent and time-dependent. However the uptake of L929 cell had a clear difference with P. aeruginosa at the same time and concentration intervals(P < 0.05).The increasing laser energy density had a high inactivation effect of on P. aeruginosa at the same Tetra-ATPP-Lys-concentration(P < 0.05). Post-antibiotic effect of Tetra-ATPP-Lys -PACT was dose-dependent(P < 0.05). Bacterial viability which evaluated by the flow cytometry method demonstrated that the proportion of viable bacteria is decreased with the photosensitizer dose-dependent. The morphology and microstructure of P. aeruginosa after Tetra-ATPP-Lys -PACT was demonstrated by a scanning electron microscope(SEM). After PACT, the morphology of P. aeruginosa was rod-shaped, the outer membrane surface was rough, and the bacteria were dry flat, sunken, shrunk and deformed. CONCLUSIONS: Cationic porphyrin photosensitizer had a great damage effect on P. aeruginosa under the PACT, which can effectively destroy the microstructure of bacteria and lead to bacterial inactivation and death.

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China is the foremost global consumer, producer, and exporter of fresh apples. In 2021, China produced roughly 44 million tons of apples and exported just over 1 million tons, a nearly 2% increase over the previous year. However, the ongoing COVID-19 pandemic has had a detrimental impact on global trade and has led to a decrease in China's agricultural exports. The present study aims to contribute to the existing body of literature by analyzing plausible macroeconomic determinants that might impact China's apple exports. We used novel dynamic autoregressive distributed lag (DYARDL) simulations to model causal relationships among fundamental economic parameters. We made use of annual time series data from 1990 to 2020 from the World Bank and China's national statistical bureau. We found that increases in apple orchard area, apple production, and trade openness had a positive impact on apple exports over both the short and long term. Conversely, decreases in the prices of exported apples, agrochemicals, and carbon emissions in the agricultural sector had a positive impact on the long-term and short-term exportation of apples. Finally, we note that pictographic illustrations from the DYARDL simulations provide corroborative evidence for our findings. Based on the study results, this study proposes that the adoption of technological advancements in apple orchards could potentially enhance apple production while simultaneously upholding environmental sustainability.

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For the treatment of bacterial infections, photodynamic antimicrobial chemotherapy (PACT) has the advantage of circumventing multi-drug resistance. In this work, new cationic photosensitizers against multi-drug resistant Proteus mirabilis (MRPM) were designed and synthesized by the conjugation of amino phenyl porphyrin with basic amino acid L-ornithine. Their photoinactivation efficacies against MRPM in vitro were reported and include the influence of laser energy, uptake, MIC and MBC, dose-dependent photoinactivation effects, membrane integrity, and fluorescence imaging. The PACT in vivo was evaluated using a wound mouse model infected by MRPM. Photosensitizer 4d displayed high photo inactivation efficacy against MRPM at 7.81 µM under illumination, and it could accelerate wound healing via bactericidal effect. These ornithine-porphyrin conjugates are potential photosensitizers for PACT in the treatment of MRPM infection.

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Paclitaxel-triethylenetetramine hexaacetic acid conjugate (PTX-TTHA), a novel semi-synthetic taxane, is designed to improve the water solubility and cosolvent toxicity of paclitaxel in several aminopolycarboxylic acid groups. In this study, the in vitro and in vivo antitumor effects and mechanisms of PTX-TTHA against triple-negative breast cancer (TNBC) and its intravenous toxicity were evaluated. Results showed the water solubility of PTX-TTHA was greater than 5 mg/mL, which was about 7140-fold higher than that of paclitaxel (<0.7 µg/mL). PTX-TTHA (10-105 nmol/L) could significantly inhibit breast cancer proliferation and induce apoptosis by stabilizing microtubules and arresting the cell cycle in the G2/M phase in vitro, with its therapeutic effect and mechanism similar to paclitaxel. However, when the MDA-MB-231 cell-derived xenograft (CDX) tumor model received PTX-TTHA (13.73 mg/kg) treatment once every 3 days for 21 days, the tumor inhibition rate was up to 77.32%. Furthermore, PTX-TTHA could inhibit tumor proliferation by downregulating Ki-67, and induce apoptosis by increasing pro-apoptotic proteins (Bax, cleaved caspase-3) and TdT-mediated dUTP nick end labeling (TUNEL) positive apoptotic cells, and reducing anti-apoptotic protein (Bcl-2). Moreover, PTX-TTHA demonstrated no sign of acute toxicity on vital organs, hematological, and biochemical parameters at the limit dose (138.6 mg/kg, i.v.). Our study indicated that PTX-TTHA showed better water solubility than paclitaxel, as well as comparable in vitro and in vivo antitumor activity in TNBC models. In addition, the antitumor mechanism of PTX-TTHA was related to microtubule regulation and apoptosis signaling pathway activation.

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Introduction: With the increasingly serious problem of bacterial drug resistance caused by NDM-1, it is an important strategy to find effective inhibitors to assist ß-lactam antibiotic treatment against NDM-1 resistant bacteria. In this study, PHT427 (4-dodecyl-N-1,3,4-thiadiazol-2-yl-benzenesulfonamide) was identified as a novel NDM-1 inhibitor and restored the susceptibility of meropenem against Enterobacteriaceae producing NDM-1. Methods: We used a high throughput screening model to find NDM-1 inhibitor in the library of small molecular compounds. The interaction between the hit compound PHT427 and NDM-1 was analyzed by fluorescence quenching, surface plasmon resonance (SPR) assay, and molecular docking analysis. The efficacy of the compound in combination with meropenem was evaluated by determining the FICIs of Escherichia coli BL21(DE3)/pET30a(+)-bla NDM-1 and Klebsiella pneumoniae clinical strain C1928 (producing NDM-1). In addition, the mechanism of the inhibitory effect of PHT427 on NDM-1 was studied by site mutation, SPR, and zinc supplementation assays. Results: PHT427 was identified as an inhibitor of NDM-1. It could significantly inhibit the activity of NDM-1 with an IC50 of 1.42 µmol/L, and restored the susceptibility of meropenem against E. coli BL21(DE3)/pET30a(+)-bla NDM-1 and K. pneumoniae clinical strain C1928 (producing NDM-1) in vitro. The mechanism study indicated that PHT427 could act on the zinc ions at the active site of NDM-1 and the catalytic key amino acid residues simultaneously. The mutation of Asn220 and Gln123 abolished the affinity of NDM-1 by PHT427 via SPR assay. Discussion: This is the first report that PHT427 is a promising lead compound against carbapenem-resistant bacteria and it merits chemical optimization for drug development.

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A series of small-molecule fluoroquinolones were synthesized, characterized by HRMS and NMR spectroscopy, and screened for their antibacterial activity against MRSA, P. aeruginosa, and E. coli as model G+/G- pathogens. Compounds 2-e, 3-e, and 4-e were more potent than the reference drug balofloxacin against MRSA and P. aeruginosa (MIC values of 0.0195 and 0.039 µg/ml for 2-e, 0.039 and 0.078 µg/ml for each of 3-e and 4-e, respectively). Analysis of the time-dependent antibacterial effect of compound 2-e toward MRSA showed that in the early logarithmic growth phase, bactericidal effects occurred, while in the late logarithmic growth phase, bacterial inhibition occurred because of concentration effects and possibly the development of drug resistance. Compound 2-e exhibited low toxicity toward normal mammalian cell lines 3T3 and L-02 and tumor cell lines A549, H520, BEL-7402, and MCF-7. The compound was not hemolytic. Atomic force microscopy (AFM) revealed that compound 2-e could effectively destroy the membrane and wall of MRSA cells, resulting in the outflow of the cellular contents. Docking studies indicated the good binding profile of these compounds toward DNA gyrase and topoisomerase IV. ADMET's prediction showed that most of the synthesized compounds followed Lipinski's "rule of five" and possessed good drug-like properties. Our data suggested that compound 2-e exhibited potent anti-MRSA activity and is worthy of further investigation.

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Ligustrazine (TMP) is a natural pyrazine alkaloid extracted from the roots of Ligusticum Chuanxiong Hort, which has the potential as an antitumor agent. A series of 33 ligustrazine-heterocycle (TMPH) derivatives were designed, synthesized, and investigated via antitumor screening assays, molecular docking analysis, and prediction of drug-like properties. TMP was attached to other heterocyclic derivatives by an 8-12 methylene alkyl chain as a linker to obtain 33 TMPH derivatives. The structures were confirmed by 1H-NMR, 13C-NMR, and high-resolution mass spectroscopy spectral (HR-MS) data. The antiproliferative activity against human breast cancer MCF-7, MDA-MB-231, mouse breast cancer 4T1, mouse fibroblast L929, and human umbilical vein endothelial HUVEC cell lines was evaluated by MTT assay. Compound 12-9 displayed significant inhibitory activity with IC50 values in the low micromolar range (0.84 ± 0.02 µM against the MDA-MB-231 cell line). The antitumor effects of compound 12-9 were further evaluated by plate cloning, Hoechst 33 342 staining, and annexin V-FITC/PI staining. The results indicated that compound 12-9 inhibited the proliferation and apoptosis of breast cancer cells. Furthermore, molecular docking of compound 12-9 into the active site of the Bcl-2, CASP-3, and PSMB5 target proteins was performed to explore the probable binding mode. The 33 newly synthesized compounds were predicted to have good drug-like properties in a theoretical study. Overall, these results indicated that compound 12-9 inhibited cell proliferation through PSMB5 and apoptosis through Bcl-2/CASP-3 apoptotic signaling pathways and had good drug-like properties. These results provided more information, and key precursor lead derivatives, in the search for effective bioactive components from Chinese natural medicines.

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With Western therapeutic techniques prevailing in Chinese therapies, some techniques that include Chinese traditional cultural features are required since some cultural factors are not considered in the Western method. Our study introduced a new technique, the moving to emptiness technique (MET), which combines Western structural progress and core factors of Chinese culture. Seventeen therapists treated 107 clients with the MET. Clients reported their target symptoms initially, and therapists helped them transfer invisible symptoms to perceivable stuff and remove their jarring stuff using the psychological emptiness area. At the end of the consultations, we found that MET could eliminate symptoms immediately. By grouping target symptoms according to their frequency, the results showed that clients in the high-frequency symptom group had higher rehabilitation rates than those in the low-frequency symptom group. Additionally, the results of the bereavement group were better than those of the non-bereavement group, indicating that the MET can significantly alleviate clients' target symptoms. In future studies, the replication and stability of the MET can be assessed by integrating questionnaires, experimental designs, and neurological equipment.

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To understand degradation routes and improve the stability of perovskite solar cells (PSCs), accelerated aging tests are needed. Here, we use elevated temperatures (up to 110°C) to quantify the accelerated degradation of encapsulated CsPbI3 PSCs under constant illumination. Incorporating a two-dimensional (2D) Cs2PbI2Cl2 capping layer between the perovskite active layer and hole-transport layer stabilizes the interface while increasing power conversion efficiency of the all-inorganic PSCs from 14.9 to 17.4%. Devices with this 2D capping layer did not degrade at 35°C and required >2100 hours at 110°C under constant illumination to degrade by 20% of their initial efficiency. Degradation acceleration factors based on the observed Arrhenius temperature dependence predict intrinsic lifetimes of 51,000 ± 7000 hours (>5 years) operating continuously at 35°C.

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Osteomyelitis is deep tissue inflammation caused by bacterial infection. If such an infection persists, it can lead to dissolution and necrosis of the bone tissue. As a result of the extensive use of antibiotics, drug-resistant bacteria are an increasingly common cause of osteomyelitis, limiting the treatment options available to surgeons. Photodynamic antibacterial chemotherapy has attracted increasing attention as a potential alternative treatment. Its advantages are a broad antibacterial spectrum, lack of drug resistance, and lack of toxic side effects. In this study, we explored the impact of the new photosensitizer LD4 in photodynamic antimicrobial chemotherapy (PACT), both alone and in combination with an antibiotic, on osteomyelitis. A rabbit tibial osteomyelitis model was employed and microbiological, histological, and radiological studies were performed. New Zealand white rabbits (n = 36) were randomly divided into a control group, antibiotic group, PACT group and PACT + antibiotic group for treatment. In microbiological analysis, a reduction in bacterial numbers of more than 99.9% was recorded in the PACT group and the PACT + antibiotic group 5 weeks after treatment (p < 0.01). In histological analysis, repair of the damaged bone tissue was observed in the PACT group, and bone repair in the PACT + antibiotic group was even more significant. In radiological analysis, the X-ray Norden score showed that the severity of bone tissue defects or destruction followed the pattern: PACT + antibiotic group < PACT group < antibiotic group < control group.

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Repetitive transcranial magnetic stimulation (rTMS) of the dorsolateral prefrontal cortex (DLPFC) is a non-invasive effective treatment for cognitive disorder, but its underlying mechanism of action remains unknown. The aim of this study was to explore the effect of a 2-week high-frequency (HF) active or sham 10 Hz rTMS on verbal memory in 40 healthy older adults. Resting-state functional magnetic resonance imaging (rs-fMRI) was used to measure functional connectivity (FC) within the default mode network (DMN). Verbal memory performance was evaluated using an auditory verbal learning test (AVLT). Additionally, we evaluated the relationship between memory improvement and FC changes within the DMN. The results revealed that HF-rTMS can enhance immediate recall and delayed recall of verbal memory and increased the FC of the bilateral precuneus (PCUN) within the DMN. The positive correlations between the immediate recall memory and the FC of the left PCUN after a 2-week intervention of HF-rTMS were detected. In conclusion, HF-rTMS may have the potential to improve verbal memory performance in older adults, which relation to FC changes in the DMN. The current findings are useful for increasing the understanding of the mechanisms of HF-rTMS, as well as guiding HF-rTMS treatment of cognitive disorders.

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We propose and numerically demonstrate an 800 Gbps silicon photonic transmitter with sub-decibel surface-normal optical interfaces. The silicon photonic transmitter is composed of eight silicon Mach-Zehnder optical modulators and an interleaved AMMI WDM device. This WDM device comprises two 1 × 4 angled MMI and a Mach-Zehnder interferometer (MZI) optical interleaver with an apodized bidirectional grating which has about -0.5 dB coupling loss. Both the Mach-Zehnder electro-optical modulators and MZI optical interleaver regard the bidirectional grating coupler as vertical optical coupler and 3-dB power splitter/combiner. By importing the S-parameter matrices of all the components which have been carefully designed in simulation software, the circuit-level model of the optical transmitter can be built up. On this basis, the static and dynamic performance characterization were carried out numerically. For NRZ modulation, the optical transmitter exhibits the overall optical loss of 4.86-6.72 dB for eight wavelength channels. For PAM4 modulation, the optical loss is about 0.5 dB larger than that of NRZ modulation, which varies between 5.38-7.27 dB. From the eye diagram test results, the WDM silicon photonic transmitter can achieve single channel data transmission at 100 Gb/s NRZ data or 50 GBaud/s PAM4 symbol rate with acceptable bit error rate.