Objective:To develop fluorescent nanoprobes with aggregation-induced emission characteristics and to systematically evaluate their optical properties, biosafety, anti-tumor activity, and imaging capability, thereby assessing their potential for early precision diagnosis and treatment of oral cancer in mice.Methods:Control probes (PEG@TPD) were prepared by encapsulating ( E)-4-(2-(4′-(1-phenyl-2,2-bis(4-methoxyphenyl)vinyl)biphenyl-4-yl)vinyl)-4-(dicyanomethylene)-4 H-chromene (TPD) using 1,2-distearoyl- SN-glycerol-3-phosphoethanolamine- N-polyethylene glycol 2000-maleimide as the carrier. Fluorescent nanoprobes (GE11-PEG@TPD) were subsequently fabricated by surface modification with the targeting GE11 peptide. The morphology and particle size of the nanoprobes were characterized by transmission electron microscopy and dynamic light scattering. The optical properties of the nanoprobes were analyzed using ultraviolet-visible spectrophotometry and fluorescence spectrophotometry. Mouse squamous carcinoma SCC-7 cells were randomly divided into six groups by the random number table method. The PBS, PEG@TPD, and GE11-PEG@TPD groups were not treated with light, while the PBS+L, PEG@TPD+L, and GE11-PEG@TPD+L groups were exposed to white light (25 W/cm 2, 10 min) at a nanoprobe concentration of 20 μg/ml (based on TPD concentration). Cell survival rate was assessed by the cell counting kit-8 assay. Cellular uptake, intracellular reactive oxygen species levels, and cytotoxicity were evaluated using laser scanning confocal microscopy. The apoptosis rate was evaluated by cell apoptosis assay. Twelve 6-week-old female C3H/HeN mice were randomly divided into two groups: PEG@TPD-1 group and GE11-PEG@TPD-1 group, with 6 mice in each group. Subcutaneous oral cancer models were established by injecting SCC-7 cell suspensions into the dorsal region of mice in two groups. Each mouse was intravenously administered 200 μl of PEG@TPD or GE11-PEG@TPD solution (1 mg/ml, based on TPD concentration). Tumor boundaries and scope were visualized using a small animal in vivo imaging system. At the optimal imaging time point, three mice from each group were euthanized, and major organs and tumor tissues were collected to measure probe accumulation. Statistical comparisons between two groups were performed using independent samples t-tests, while one-way or two-way analysis of variance was applied for multiple group comparisons. Results:Both PEG@TPD and GE11-PEG@TPD exhibited a relatively regular sphere, with average particle sizes of (92.76±8.80 and 117.50±6.40) nm, respectively. PEG@TPD showed two obvious absorption peaks at 352 and 444 nm. GE11 peptide showed a polypeptide characteristic absorption peak at 280 nm, GE11-PEG@TPD showed three characteristic absorption peaks at 280, 352 and 444 nm. Under dark conditions, cell survival rate remained above 80% even at a concentration of 160 μg/ml. After light irradiation, cell survival rate in the PEG@TPD+L group at 20 and 40 μg/ml [(68.2±5.2)% and (48.6±7.1)%] were higher than those in the GE11-PEG@TPD+L group [(55.0±2.8)% and (30.0±9.2)%], with statistically significant differences ( P<0.05, 0.01). At incubation time points of 2, 4, and 6 h, the relative fluorescence intensity of the GE11-PEG@TPD group (119.4±10.2, 192.9±14.2, and 234.1±4.8) were higher than those of the PEG@TPD group (98.6±7.5, 163.8±3.1, 204.6±11.2), with statistically significant differences (all P<0.05). The relative fluorescence intensity of the PEG@TPD+L and GE11-PEG@TPD+L group (68.5±4.7 and 86.8±10.0) were higher than those in the PBS, PEG@TPD, GE11-PEG@TPD, and PBS+L groups (6.1±8.0, 7.6±1.8, 4.7±4.2 and 21.1±7.6), with statistically significant differences (all P<0.01). And the difference between the GE11-PEG@TPD+L and PEG@TPD+L groups was also statistically significant ( P<0.05). Viable cell proportions in the PBS, PEG@TPD, GE11-PEG@TPD, and PBS+L groups all exceeded 95.0%, while those in the PEG@TPD+L and GE11-PEG@TPD+L groups decreased to (11.1±3.7)% and (4.3±1.1)%, respectively, with a statistically significant difference between them ( P<0.05). The apoptotic cell proportions in the PEG@TPD+L and GE11-PEG@TPD+L groups [(40.5±4.3)% and (55.3±7.4)%] were higher than those in the PBS, PEG@TPD, GE11-PEG@TPD, and PBS+L groups [(27.3±2.0)%, (28.2±1.9)%, (28.6±1.2)%, and (29.7±3.0)%], with statistically significant differences ( P<0.05, 0.01). Moreover, the difference between the GE11-PEG@TPD+L and the PEG@TPD+L groups was also statistically significant ( P<0.01). The mean fluorescence intensities of the GE11-PEG@TPD-1 group at 1, 3, 5, 8, and 24 h, as well as in ex vivo tumor tissues[(5.2±0.8, 5.9±0.7, 6.6±1.0, 7.9±0.6, 7.8±0.7 and 20.6±3.5)×10 6 p/s/cm 2/sr] were all higher than those in the PEG@TPD-1 group [(3.2±0.7, 4.2±0.7, 4.6±0.9, 5.1±0.9, 4.7±0.9 and 14.2±1.8)×10 6 p/s/cm 2/sr], with statistically significant differences ( P<0.05, 0.01). Conclusions:The fluorescent nanoprobes exhibit uniform particle size, high photostability, and good biocompatibility. They demonstrate significant tumor-killing effects at the cellular level and possess tumor-targeting capability in vivo, showing promising application potential for the early precision diagnosis and treatment of oral cancer.

BACKGROUNDThoracic endovascular aortic repair (TEVAR) is an emerging treatment modality, which has been rapidly embraced by clinicians treating thoracic aortic disease. However, the clinical manifestations of systemic inflammatory response after TEVAR as post-implantation syndrome (PIS) resemble the perioperative infection. This study aimed to evaluate changes and diagnostic value of procalcitonin (PCT) and other traditional inflammatory markers for infections after TEVAR.

METHODSWe conducted a prospective clinical study that enrolled 162 consecutive aortic dissection cases, who underwent TEVAR in our institution between July 2011 and November 2012. The PCT, C-response protein (CRP), erythrocyte sedimentation rate (ESR) and blood routine examination were monitored before the operation and on days 1, 2, 3 and 5 after the operation. The diagnosis of infection was confirmed by the infection control committee with reference to Hospital Acquired Infection Diagnostic Criteria Assessment, released by the Ministry of Health of the People's Republic of China.

RESULTSPost endovascular repair of thoracic aorta, PCT changes significantly at different time points (χ(2) = 13.225, P = 0.021), without significant difference between the PIS group and the control group (0.24 ± 0.04 vs.0.26 ± 0.10, P = 0.804). PCT values were significantly higher in the first day after TEVAR than the preoperative levels (0.18 ± 0.03 vs. 0.11 ± 0.02, P < 0.001). Compared with PIS patients, the level of PCT, CRP, White blood cell (WBC) and neutrophil (NEU) in the infection patients elevated significantly (relatively χ(2) = 6.062, P = 0.048; χ(2) = 6.081, P = 0.048; χ(2) = 11.030, P = 0.004; χ(2) = 14.632, P = 0.001). According to the ROC analysis, the PCT levels in the first day after TEVAR (AUC = 0.785, P = 0.012) had better predictive values of infection than WBC, NEU CRP and ESR (AUC = 0.720, P = 0.040; AUC = 0.715, P = 0.045; AUC = 0.663, P = 0.274; AUC = 0.502, P = 0.991). The best predictive index was the changes of PCT between preoperative and postoperative (PCT), which possess AUC as 0.803 (P = 0.014). And PCT = 0.055 could be considered as an infection diagnosis cutoff value with a sensitivity of 83.3% and specificity 69.0%.

CONCLUSIONSPCT provides better diagnostic value of infection compared with other inflammatory markers. The potential applications of PCT in differential diagnosis of PIS and infection after percutaneous TEVAR deserve further studies.

Adult ; Aged ; Blood Sedimentation ; C-Reactive Protein ; metabolism ; Calcitonin ; metabolism ; Calcitonin Gene-Related Peptide ; Diagnosis, Differential ; Female ; Humans ; Male ; Middle Aged ; Prospective Studies ; Protein Precursors ; metabolism ; Vascular Surgical Procedures