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Poor penetration into the tumor parenchyma and the reduced therapeutic efficacy of anticancer drugs and other medications are the major problems in tumor treatment. A new tumor-homing and penetrating peptide, iRGD (CRGDK/RGPD/EC), can be effectively used to combine and deliver imaging agents or anticancer drugs into tumors. The different “vascular zip codes” expressed in different tissues can serve as targets for docking-based (synaptic) delivery of diagnostic and therapeutic molecules. αv-Integrins are abundantly expressed in the tumor vasculature, where they are recognized by peptides containing the RGD integrin recognition motif. The iRGD peptide follows a multistep tumor-targeting process: First, it is proteolytically cleaved to generate the CRGDK fragment by binding to the surface of cells expressing αv integrins (αvβ3 and αvβ5). Then, the fragment binds to neuropilin-1 and penetrates the tumor parenchyma more deeply. Compared with conventional RGD peptides, the affinity of iRGD for αv integrins is in the mid to low nanomolar range, and the CRGDK fragment has a stronger affinity for neuropilin-1 than that for αv integrins because of the C-terminal exposure of a conditional C-end Rule (CendR) motif (R/KXXR/K), whose receptor proved to be neuropilin-1. Consequently, these advantages facilitate the transfer of CRGDK fragments from integrins to neuropilin-1 and consequently deeper penetration into the tumor. Due to its specific binding and strong affinity, the iRGD peptide can deliver imaging agents and anticancer drugs into tumors effectively and deeply, which is useful in detecting the tumor, blocking tumor growth, and inhibiting tumor metastasis. This review aims to focus on the role of iRGD in the imaging and treatment of various cancers.

Acute pancreatitis is a common clinical acute abdomen. Imaging examinations play an important role in the management of acute pancreatitis. MR imaging is a noninvasive examination with high tissue contrast and a variety of acquisition sequences that can help determine the diagnosis, complications and severity of acute pancreatitis. The acute pancreatitis classification working group modified the Atlanta classification in 2012 to improve clinical evaluations and standardize the radiologic nomenclature for acute pancreatitis. In particular, the redefinition of necrotizing pancreatitis offers a new understanding of this disease. In clinical practice, there is still a lack of unifying standards between radiologists and physicians, such as for the imaging features of pseudocysts, walled-off necrosis, peripancreatic necrosis and especially for the MR imaging features of acute pancreatitis. In this article, we review the 2012 revised Atlanta classification of acute pancreatitis and recent advances in the clinical applications of MR imaging (MRI) in acute pancreatitis by showing how MRI can provide more optimized information for clinical diagnosis and treatment plan.

PurposeTo investigate the biomarkers change in serum and the correlation with quantitative MRI markers by histopathologic evaluation of the cartilage in surgically-induced osteoarthritis(OA) rabbit model.Materials and MethodsThirty-six mature New Zealand rabbits were used. Eighteen rabbits were divided into six groups randomly and equally and subjected to surgery using the improved Hulth method. The other eighteen rabbits were also allocated into six groups randomly and equally which served as the control. At multiple time points after surgery, the BMP-2, CTX-II and COMP levels in the serum were analyzed by ELISA, and quantitative MRI was performed. Histopathology was examined with HE, and Mankin scores were assessed. The changes in the biochemical biomarkers and imaging markers in the OA groups were compared with those in the control groups using paired-samples T tests. The correlation of quantitative MRI markers with biomarkers and Mankin scores were analyzed. The analysis of Mankin scores was conducted with non-parametric wilcoxon signed rank tests.ResultsThe BMP-2 levels were increased at various times after surgery, and significant differences were observed between the OA and control groups(all the P values <0.001). CTX-II levels were significantly elevated at several intervals after surgery, including W2, W8, W12, W16 and W20(P=0.019, 0.004, 0.007, <0.001 and 0.016 respectively), but not at W4(P=0.764). Significant differences in the COMP levels from W2 to W20 were observed between the OA and the control groups(P<0.001, <0.001, <0.001, <0.001,=0.002 and =0.004 respectively). The T2 values increased at W8 post-surgery and were significantly different between the OA and control groups(P=0.001, <0.001, <0.001 and <0.001 respectively). T2* values increased from W2 to W20 and were significantly different between the control and OA groups(P=0.002, =0.001, <0.001, <0.001, =0.001 and <0.001 respectively). T2 values had significant correlation with BMP-2 and CTX-II(P<0.001 and =0.014), except COMP(P=0.305)., while the correlation of T2* values with BMP-2, CTX-II and COMP was significant(P=0.043, 0.005 and 0.025 respectively). In addition, a positive correlation of T2 values and Mankin scores was observed(P<0.001).ConclusionWith the relevance of the multiple time point analysis of the serum biomarkers and imaging markers compared with histological findings, BMP-2, CTX-II and COMP combined with T2 and T2* can be used to reflect and monitor OA progression potentially.

The outbreak of novel coronavirus disease 2019 (COVID-19) first occurred in Wuhan, Hubei Province, China, and spread across the country and worldwide quickly. It has been defined as a major global health emergency by the World Health Organization (WHO). As this is a novel virus, its diagnosis is crucial to clinical treatment and management. To date, real-time reverse transcription-polymerase chain reaction (RT-PCR) has been recognized as the diagnostic criterion for COVID-19. However, the results of RT-PCR can be complemented by the features obtained in chest computed tomography (CT). In this review, we aim to discuss the diagnosis and main CT features of patients with COVID-19 based on the results of the published literature, in order to enhance the understanding of COVID-19 and provide more detailed information regarding treatment.

Pancreatic carcinoma is an extremely high-grade malignant tumor with �ast development and high mortality. The incidence o� pancreatic carcinoma continues to increase. Peripancreatic invasion and metastasis are the main characteristics and important prognostic �actors in pancreatic carcinoma, especially invasion into the nervous system; pancreatic nerve innervation includes the intrapancreatic and extrapancreatic nerves. A strong grasp o� pancreatic nerve innervation may contribute to our understanding o� pancreatic pain modalities and the metastatic routes �or pancreatic carcinomas. Computed tomography (CT) and magnetic resonance imaging (MRI) are help�ul techniques �or depicting the anatomy o� extrapancreatic nerve innervation. The purpose o� the present work is to show and describe the anatomy o� the extrapancreatic neural plexus and to elucidate its characteristics using CT and MRI, drawing on our own previous work and the research findings of others.

Osteoarthritis (OA) is the most common joint disease in elderly individuals and seriously affects quality of life. OA has often been thought to be caused by body weight load, but studies have increasingly shown that OA is an inflammation-mediated metabolic disease. The current existing evidence suggests that OA is associated with obesity-related chronic inflammation as well as abnormal lipid metabolism in obesity, such as fatty acids (FA) and triglycerides. Adiponectin, a cytokine secreted by adipose tissue, can affect the progression of OA by regulating obesity-related inflammatory factors. However, the specific molecular mechanism has not been fully elucidated. According to previous research, adiponectin can promote the metabolism of FA and triglycerides, which indicates that it is a potential protective factor for OA through many mechanisms. This article aims to review the mechanisms of chronic inflammation, FA and triglycerides in OA, as well as the potential mechanisms of adiponectin in regulating chronic inflammation and promoting FA and triglyceride metabolism. Therefore, adiponectin may have a protective effect on obesity-related OA, which could provide new insight into adiponectin and the related mechanisms in OA.

Gastrointestinal tumors (GTs) are among the most common tumors of the digestive system and are among the leading causes of cancer death worldwide. Functional magnetic resonance imaging (MRI) is crucial for assessment of histopathological changes and therapeutic responses of GTs before and after chemotherapy and radiotherapy. A new functional MRI technique, intravoxel incoherent motion (IVIM), could reveal more detailed useful information regarding many diseases. Currently, IVIM is widely used for various tumors because the derived parameters (diffusion coefficient, D; pseudo-perfusion diffusion coefficient, D*; and perfusion fraction, f) are thought to be important surrogate imaging biomarkers for gaining insights into tissue physiology. They can simultaneously reflect the microenvironment, microcirculation in the capillary network (perfusion) and diffusion in tumor tissues without contrast agent intravenous administration. The sensitivity and specificity of these parameters used in the evaluation of GTs vary, the results of IVIM in GTs are discrepant and the variability of IVIM measurements in response to chemotherapy and/or radiotherapy in these studies remains a source of controversy. Therefore, there are questions as to whether IVIM diffusion-weighted MRI is feasible and helpful in the evaluation of GTs, and whether it is worthy of expanded use.