Improved Performance of Compartments in Detecting the Activity of Axial Spondyloarthritis Based on IVIM DWI with Optimized Threshold b Value

Purpose. To explore the diagnostic performance of the optimized threshold b values on IVIM to detect the activity in axial spondyloarthritis (axSpA) patients. Method. 40 axSpA patients in the active group, 144 axSpA patients in the inactive group, and 20 healthy volunteers were used to evaluate the tissue diffusion coefficient ( D slow ), perfusion fraction ( f ), and pseudodiffusion coefficient ( D fast ) with b thresholds of 10, 20, and 30 s/mm2. The Kruskal-Wallis test and one way ANOVA test was used to compare the different activity among the three groups in axSpA patients, and receiver operating characteristic (ROC) curve analysis was applied to evaluate the performance for D slow , f , and D fast to detect the activity in axSpA patients, respectively. Results. D slow demonstrated a statistical difference between two groups ( P < 0.05 ) with all threshold b values. With the threshold b value of 30 s/mm2, f could discriminate the active from control groups ( P < 0.05 ). D slow had similar performance between the active and the inactive groups with threshold b values of 10, 20, and 30 s/mm2 (AUC: 0.877, 0.882, and 0.881, respectively, all P < 0.017 ). Using the optimized threshold b value of 30 s/mm2, f showed the best performance to separate the active from the inactive and the control groups with AUC of 0.613 and 0.738 (both P < 0.017 ) among all threshold b values. Conclusion. D slow and f exhibited increased diagnostic performance using the optimized threshold b value of 30 s/mm2 compared with 10 and 20 s/mm2, whereas D fast did not.

Neutrophils mediated multistage nanoparticle delivery for prompting tumor photothermal therapy

Background Neutrophil-based drug delivery system possesses excellent advantages in targeting at tumour because neutrophils are easily recruited by chemotactic factor in tumor microenvironment. Herein, we developed a novel tactic of multistage neutrophils-based nanoparticle delivery system for promoting photothermal therapy (PTT) of lung cancer. Results Au nanorod (AuNR) was successfully modified with bovine serum albumin (AuNRB) and further conjugated with RGD (AuNRBR), followed by neutrophil internalisation to obtain neutrophils-based delivery system (AuNRBR/N). The engineered neutrophils efficiently migrated across the epithelial cells due to inflammatory signal. They exhibited better toxicity against Lewis cells with laser irradiation in vitro. Moreover, AuNRBR/N showed significantly more targetability to tumour tissue compared with cell carrier-free AuNRBR, as demonstrated in Lewis tumour-bearing mice. The enhanced tumour homing efficiency of AuNRBR/N together with subsequently released AuNRBR from the neutrophils was favourable for further deep tissue diffusion and contributed to the inhibition of the tumour growth in PTT and improved survival rate (over 120 days). Conclusions Overall results illustrated that the design of cell-based nanoparticle delivery system for PTT of cancer is promising.

Neutrophils Mediated Multistage Nanoparticle Delivery for Prompting Tumor Photothermal Therapy

Background : Neutrophil-based drug delivery system possesses excellent advantages in targeting at tumour because neutrophils are easily recruited by chemotactic factor in tumor microenvironment. Herein, we developed a novel tactic of multistage neutrophils-based nanoparticle delivery system for promoting photothermal therapy (PTT) of lung cancer. Results: Au nanorod (AuNR) was successfully modified with bovine serum albumin (AuNRB) and further conjugated with RGD (AuNRBR), followed by neutrophil internalisation to obtain neutrophils-based delivery system (AuNRBR/N). The engineered neutrophils efficiently migrated across the epithelial cells due to inflammatory signal. They exhibited better toxicity against Lewis cells with laser irradiation in vitro . Moreover, AuNRBR/N showed significantly more targetability to tumour tissue compared with cell carrier-free AuNRBR, as demonstrated in Lewis tumour-bearing mice. The enhanced tumour homing efficiency of AuNRBR/N together with subsequently released AuNRBR from the neutrophils was favourable for further deep tissue diffusion and contributed to the inhibition of the tumour growth in PTT and improved survival rate (over 120 days). Conclusions: Overall results illustrated that the design of cell-based nanoparticle delivery system for PTT of cancer is promising.

Neutrophils Mediated Multistage Nanoparticle Delivery for Prompting Tumor Photothermal Therapy

Background Neutrophil-based drug delivery system possesses excellent advantages in targeting at tumour because neutrophils are easily recruited by chemotactic factor in tumor microenvironment. Herein, we developed a novel tactic of multistage neutrophils-based nanoparticle delivery system for promoting photothermal therapy (PTT) of lung cancer. Results Au nanorod (AuNR) was successfully modified with bovine serum albumin (AuNRB) and further conjugated with RGD (AuNRBR), followed by neutrophil internalisation to obtain neutrophils-based delivery system (AuNRBR/N). The engineered neutrophils efficiently migrated across the epithelial cells due to inflammatory signal. They exhibited better toxicity against Lewis cells with laser irradiation in vitro. Moreover, AuNRBR/N showed significantly more targetability to tumour tissue compared with cell carrier-free AuNRBR, as demonstrated in Lewis tumour-bearing mice. The enhanced tumour homing efficiency of AuNRBR/N together with subsequently released AuNRBR from the neutrophils was favourable for further deep tissue diffusion and contributed to the inhibition of the tumour growth in PTT and improved survival rate (over 120 days). Conclusions Overall results illustrated that the design of cell-based nanoparticle delivery system for PTT of cancer is promising.

Magnetic resonance measurements of cellular and sub-cellular membrane structures in live and fixed neural tissue

We develop magnetic resonance (MR) methods for measuring real-time changes of tissue microstructure and membrane permeability of live and fixed neural tissue. Diffusion and exchange MR measurements are performed using the large static gradient produced by a single-sided permanent magnet. Using tissue delipidation methods, we show that water diffusion is restricted solely by lipid membranes. Most of the diffusion signal can be assigned to water in tissue which is far from membranes. The remaining 25% can be assigned to water restricted on length scales of roughly a micron or less, near or within membrane structures at the cellular, organelle, and vesicle levels. Diffusion exchange spectroscopy measures water exchanging between membrane structures and free environments at 100 s−1.

Multimodality imaging and mathematical modelling of drug delivery to glioblastomas

Patients diagnosed with glioblastoma, an aggressive brain tumour, have a poor prognosis, with a median overall survival of less than 15 months. Vasculature within these tumours is typically abnormal, with increased tortuosity, dilation and disorganization, and they typically exhibit a disrupted blood–brain barrier (BBB). Although it has been hypothesized that the ‘normalization’ of the vasculature resulting from anti-angiogenic therapies could improve drug delivery through improved blood flow, there is also evidence that suggests that the restoration of BBB integrity might limit the delivery of therapeutic agents and hence their effectiveness. In this paper, we apply mathematical models of blood flow, vascular permeability and diffusion within the tumour microenvironment to investigate the effect of these competing factors on drug delivery. Preliminary results from the modelling indicate that all three physiological parameters investigated—flow rate, vessel permeability and tissue diffusion coefficient—interact nonlinearly to produce the observed average drug concentration in the microenvironment.

Hamman’s Syndrome: A Rare Cause of Chest Pain in a Postpartum Patient

Hamman’s syndrome is a rare condition represented by spontaneous pneumomediastinum and subcutaneous emphysema. Excessive Valsalva maneuver during vaginal delivery and excessive retching, coughing, and straining are frequently reported causes. The incidence of Hamman’s syndrome is believed to be 1 in 100,000 deliveries. The pathophysiology of this condition is rupture of alveoli and seepage of air through bronchovascular connective tissue. Diffusion of air to subcutaneous tissues results in subcutaneous emphysema. In most cases, it is a benign condition and resolves spontaneously. In life-threatening cases, a cardiac tamponade can ensue. Chest X-ray is a useful early diagnostic technique. We report a case of a twenty-four-year-old female who was diagnosed with Hamman’s syndrome after prolonged, exhaustive labor.