ABSTRACT
The main function of anterior cruciate ligament (ACL) is to maintain stability of the knee joint and prevent anterior displacement of the tibial plateau. ACL injury accounts for more than 50% of the knee joint injuries. If not timely handled, it will increase the risk of secondary injuries to structures such as the meniscus and cartilage, causing chronic pain and degeneration of the knee joint. Although most ACL injuries can be determined by their direct signs on MRI, the identification of complex situations and partial tears of ACL are still not satisfactory, which subsequently affects treatment strategies. After ACL injury, changes in anatomical relationship of the knee joint can also lead to morphological changes in other structures such as the posterior cruciate ligament (PCL) on MRI, and these indirect signs can assist in the diagnosis of ACL injury. The authors reviewed the application of MRI-related indicators of PCL in diagnosing ACL injury, hoping to provide references and new ideas for clinical decision-making.
ABSTRACT
Objective To develop MSNs loaded with ICG and investigate its diagnostic value and photodynamic therapeutic value in the experimental pancreatic cancer. Methods ICG was loaded into MSNs to prepare the ICG/MSNs probe. The probe toxicity was evaluated by MTT assays. Near?infrared stereo fluores?cence microscope ( NISFM) was applied to investigate whether the ICG/MSNs would be uptaken by the human pancreatic cancer cells. After incubated with PBS, ICG (10μg/ml), MSNs or ICG/MSNs (10μg/ml ICG) for 24 h and treated with photodynamic therapy (PDT, (780±25) nm laser, 500 mW/cm2), the human pancreatic cancer cells survival rate was determined by MTT method. The human pancreatic cancer cells were implanted into nude mice to prepare subcutaneous tumor models. The distribution of ICG/MSNs in sub?cutaneous tumor models was studied with in vivo imaging system ( IVIS ) . With reference to the injection dose of ICG(0.5 mg/kg), the mice in PBS group, ICG group, ICG/MSNs group (4 mice per group) were injected via tail vein with 150μl PBS, ICG solution and ICG/MSNs solution, respectively. After treated by PDT for 48 h, the mice were observed by IVIS for 2 weeks using BLI to evaluate the therapeutic effect of PDT. NISFM was used to observe the fluorescence in tumor region. One?way analysis of variance was used to analyze the data. Results The diameter of ICG/MSNs was about 100 nm and it could be uptaken by human pancreatic cancer cells. After treated by PDT, the survival rates of human pancreatic cancer cells were (24?5±5.0)%, (81.2±1.6)%, (90.7±2.0)% and (93.4±1.7)% in ICG/MSNs group, ICG group, MSNs group and PBS group, respectively(F=212.289, P<0.05). ICG/MSNs group showed better therapeutic effect than ICG group( P<0.05) . After 12 d treated by PDT, the tumor did not recur or grow in ICG/MSNs group, but grew obviously in ICG group and PBS group. The BLI of tumor area in PBS group, ICG group and ICG/MSNs group were (61.2±7.7)×108, (56.7±9.0)×108 and (2.4±1.5)×108, respectively(F=67?098, P<0.05) . And the difference between ICG/MSNs and ICG group was statistically significant ( P<0.05) . Meanwhile, the NISFM showed clearly the tumor location with ICG/MSNs. Conclusions ICG/MSNs have good biocompatibility, good PDT effect on pancreatic cancer cells and pancreatic cancer xeno?grafts. Near?infrared fluorescence imaging with ICG/MSNs could delineate the tumor location.