A highly tumor-targeted nanoparticle of podophyllotoxin penetrated tumor core and regressed multidrug resistant tumors

Podophyllotoxin (PPT) exhibited significant activity against P-glycoprotein mediated multidrug resistant (MDR) tumor cell lines; however, due to its poor solubility and high toxicity, PPT cannot be dosed systemically, preventing its clinical use for MDR cancer. We developed a nanoparticle dosage form of PPT by covalently conjugating PPT and polyethylene glycol (PEG) with acetylated carboxymethyl cellulose (CMC-Ac) using one-pot esterification chemistry. The polymer conjugates self-assembled into nanoparticles (NPs) of variable sizes (20–120 nm) depending on the PPT-to-PEG molar ratio (2–20). The conjugate with a low PPT/PEG molar ratio of 2 yielded NPs with a mean diameter of 20 nm and released PPT at ∼5%/day in serum, while conjugates with increased PPT/PEG ratios (5 and 20) produced bigger particles (30 nm and 120 nm respectively) that displayed slower drug release (∼2.5%/day and ∼1%/day respectively). The 20 nm particles exhibited 2- to 5-fold enhanced cell killing potency and 5- to 20-fold increased tumor delivery compared to the larger NPs. The biodistribution of the 20 nm PPT-NPs was highly selective to the tumor with 8-fold higher accumulation than all other examined tissues, while the larger PPT-NPs (30 and 120 nm) exhibited increased liver uptake. Within the tumor, >90% of the 20 nm PPT-NPs penetrated to the hypovascular core, while the larger particles were largely restricted in the hypervascular periphery. The 20 nm PPT-NPs displayed significantly improved efficacy against MDR tumors in mice compared to the larger PPT-NPs, native PPT and the standard taxane chemotherapies, with minimal toxicity.     

Helicobacter pylori and gastric hyperacidity,and their association with recurrent aphthous stomatitis

Helicobacter pylori is an established cause of gastric ulcers. Its role in causing recurrent aphthous stomatitis (RAS) remains controversial. Fifty-two RAS patients and 52 sex-matched controls were recruited in this case–control study. All subjects were screened for hematinic deficiencies and H. pylori. The latter was assessed quantitatively using the ¹⁴C-urea breath test. The χ² test and Wilcoxon signed ranks test were used to compare H. pylori and hematinic indices between cases and controls, while conditional logistic regression was used to assess the associations between the occurrence of RAS and independent factors. H. pylori was positive in 56.7% of the overall sample, with no difference between RAS patients (50.8%) and controls (49.2%) (P = 0.843). The median H. pylori and haematological indices values did not show any association with ulcer diameter, number, or frequency. Interestingly, gastric hyperacidity was significantly associated with RAS, and this association was independent from tobacco smoking, alcohol drinking, and H. pylori (odds ratio 14.99, 95% confidence interval 2.47–90.95; P = 0.003). This study found no association between H. pylori and RAS. The association between RAS and gastric hyperacidity suggests that gastric refluxate, not H. pylori, has an effect on the oral mucosa that favours an ulcerative change.     

Three-dimensional finite element analysis of intramedullary nail with different materials in the treatment of intertrochanteric fractures

Intramedullary nails are the common treatment options for femoral intertrochanteric fractures. However, aseptic loosening is considered to be one of the primary forms of failure that can be caused by the stress shielding between the bone and implants. The matching in mechanical properties of implant and bone is a key issue to prevent this failure. Polyetheretherketone (PEEK) and Function-graded (FG) materials are widely used in clinical because of their excellent mechanical properties. In this study, to investigate the biomechanical behaviors of intramedullary nails made of Ti-6Al-4V alloy, Stainless Steel (SS), PEEK and two FG materials, three-dimensional finite element models of intertrochanteric fracture femur with intramedullary nail were constructed with ABAQUS. The maximum von Mises stress on the femoral fracture surface fixed by PEEK intramedullary nail was the largest, followed by FG intramedullary nail, which help stimulate bone growth and subsequently reduce fracture healing time. Compared with traditional metal intramedullary nails, PEEK and FG implants might increase von Mises stress along the same path in the proximal femur. The results showed that PEEK and FG intramedullary nails obviously changed the stress distributions in the bone and reduced stress shielding. This finding indicated that PEEK and FG intramedullary nails have the potential to become alternatives to the conventional metal intramedullary nails.     

“Cheese Wire” Fenestration of Dissection Intimal Flap to Facilitate Thoracic Endovascular Aortic Repair in Chronic Dissection

Thoracic endovascular aortic repair (TEVAR) for aneurysmal chronic dissection is often complicated by retrograde filling of the false lumen and dissected distal landing zone. A “cheese wire”-style fenestration of the dissection intimal flap can create a landing zone facilitating TEVAR. This technique successfully aided TEVAR in 3 patients with an average age of 57.3 years. Complications included type III endoleak requiring relining and renal artery occlusion requiring stent placement. Average duration of clinical follow-up was 19 ± 4 months. Imaging follow-up was 8 ± 10 months. All patients have survived for more than 1 year without aneurysm enlargement.     

“龙虎交战”针法针刺八脉交会穴对偏头痛患者头痛天数及血清CGRP表达的影响＊

目的 观察“龙虎交战”针法针刺八脉交会穴对无先兆偏头痛（Migraine without aura，MO）患者头痛天数及外周血降钙素基因相关肽（Calcitonin gene related peptide，CGRP）表达水平的影响。方法 按照头痛程度将90例MO受试者区层随机分为治疗Ⅰ组、治疗Ⅱ组和对照组各30例。治疗Ⅰ组施以“龙虎交战”针法针刺八脉交会穴（外关和足临泣），治疗Ⅱ组施以平补平泻针法针刺八脉交会穴（外关和足临泣），对照组施以平补平泻针法针刺非经非穴点，每次留针30分钟，5次/周，共治疗20次。于治疗前、治疗结束4周后的随访分别记录三组患者头痛天数的变化情况以判定疗效，并采集患者治疗前、治疗结束4周后随访的肘部静脉血用ELISA法检测血清中的CGRP含量的变化。结果 ①各组治疗前患者的头痛天数无显著差异（Ｐ > 0.05），治疗Ⅰ组、治疗Ⅱ组和对照组治疗结束4周后随访的头痛天数较治疗前均显著降低（Ｐ < 0.05）；治疗Ⅰ组头痛天数的降低显著优于治疗Ⅱ组和对照组（Ｐ < 0.001），治疗Ⅱ组头痛天数的降低显著优于对照组（Ｐ < 0.05）；②3组治疗前CGRP的表达无显著差异，治疗Ⅰ组、治疗Ⅱ组治疗结束4周后随访CGRP的表达较治疗前均显著下降（Ｐ < 0.001），对照组治疗结束4周后随访CGRP的表达较治疗前差异无显著性（Ｐ > 0.05）；治疗Ⅰ组CGRP治疗结束4周随访的表达较治疗Ⅱ组和对照组均显著下降（Ｐ < 0.01），治疗Ⅱ组CGRP的表达较对照组显著下降（P < 0.01）。结论 ①八脉交会穴施以“龙虎交战”针法针刺能明显改善MO患者的头痛天数，同时降低MO患者血清CGRP的表达水平，这可能是针刺八脉交会穴治疗MO的机制之一；②非经非穴点的针刺效应无持续性，而八脉交会穴的针刺效应具有持续性；③八脉交会穴可以充分发挥复式针刺手法的治疗效应，提示我们在临床上治疗疾病时不仅要注意腧穴配伍，恰当的针刺手法更是提高临床疗效、事半功倍的关键。     

Posterior Tibial Tendinopathy and Osteopenia as Primary Symptoms of Celiac Disease: A Case Report

This case report describes posterior tibial tendon (PTT) tendinopathy, valgus deformity with tenosynovitis, and osteopenia at the medial malleolus as the primary symptoms of a young patient with celiac disease (CD) without gastrointestinal symptoms. CD is an autoimmune condition that is a chronic inflammatory disorder of the small intestine triggered by ingestion of gluten in individuals with a particular genetic background. Without typical gastrointestinal symptoms, CD patients are often misdiagnosed or undiagnosed. The patient was diagnosed with CD by duodenal biopsy. He underwent a surgical procedure, including medial displacement calcaneal osteotomy, tenosynovectomy of the PTT and flexor digitorum longus (FDL), FDL transfer to the navicular for a pes planovalgus deformity, and drilling of the medial malleolus for a stress reaction. The mechanism of the PTT tear and associated heel valgus deformity was assumed to be related to the fact that his heel alignment on the affected side changed gradually from normal to valgus and pes planus owing to CD and mechanical stress, because his normal-side heel alignment was neutral before surgery and at final follow-up. His operated ankle was pain-free, with full range of motion, 1.5 years after surgery. The patient was able to restart running and exercise gradually. Foot and ankle specialists should consider the possibility of CD in patients presenting with a PTT tear without injury or trauma and osteopenia with no obvious reason.