Live-cell imaging to analyze intracellular aggregation of recombinant IgG in CHO cells

Recombinant immunoglobulin G (IgG) aggregates are formed during their production. However, the process underlying intracellular/extracellular aggregation in cell culture conditions is not well understood, and no effective method exists to assess IgG aggregates. Here, we establish an approach to detect intracellular aggregates using AF.2A1, a small artificial protein that binds to non-native IgG conformers and aggregates. Fluorescent-labeled AF.2A1 is prepared via conjugation and transfected into antibody-producing Chinese hamster ovary (CHO) cells. Micrographic images show intracellular IgG aggregates in CHO cells. The relative amount of intracellular aggregates (versus total intracellular IgG) differed depending on the type of additives used during cell culture. Interestingly, the relative amount of intracellular aggregates moderately correlates with that of in vitro extracellular IgG aggregates, suggesting they are secreted. This method will allow the investigation of antibody aggregation in cells, and may guide the production of therapeutic antibodies with high yield/quality

One strategy for arthroscopic suture fixation of tibial intercondylar eminence fractures using the Meniscal Viper Repair System

<p>Abstract</p> <p>Background</p> <p>Principles for the treatment of tibial intercondylar eminence fracture are early reduction and stable fixation. Numerous ways to treatment of this fracture have been invented. We designed a simple, low-invasive, and arthroscopic surgical strategy for tibial intercondylar eminence fracture utilizing the Meniscal Viper Repair System used for arthroscopic meniscal suture.</p> <p>Methods</p> <p>We studied 5 patients, who underwent arthroscopic suture fixation that we modified. The present technique utilized the Meniscal Viper Repair System for arthroscopic suture of the meniscus. With one handling, a high-strength ultra-high molecular weight polyethylene(UHMWPE) suture can be passed through the anterior cruciate ligament (ACL) and the loops for suture retrieval placed at both sides of ACL. Surgical results were evaluated by the presence or absence of bone union on plain radiographs, postoperative range of motion of the knee joint, the side-to-side differences measured by Telos SE, and Lysholm scores.</p> <p>Results</p> <p>The reduced position achieved after surgery was maintained and good function was obtained in all cases. The mean distance of tibia anterior displacement and assessment by Lysholm score showed good surgical results.</p> <p>Conclusion</p> <p>This method simplified the conventional arthroscopic suture fixation and increased its precision, and was applicable to Type II fractures that could be reduced, as well as surgically indicated Types III and IV. The present series suggested that our surgical approach was a useful surgical intervention for tibial intercondylar eminence fracture.</p

Footballer's Lateral Meniscus: Anterior Horn Tears of the Lateral Meniscus with a Stable Knee

This paper aimed to identify the characteristics of isolated anterior horn tear of the lateral meniscus in footballers who underwent arthroscopic surgery. We identified 8 patients with stable knee and no ligament injury, who had only isolated anterior horn tear of the lateral meniscus between 2007 and 2009. All 8 patients were footballers, comprising 7 men and 1 woman with mean age of 18.6 years. Arthroscopy revealed multiple longitudinal tears in 2 patients, longitudinal tear in 2 patients, degenerative tear in 3 patients, and flap tear in 1 patient. Two patients were treated by repair, five by partial excision, and one by rasping only. The mean Lysholm score was 65 before surgery and recovered to 89 at the last followup, on average 12 months after surgery. Anterior horn tear of the lateral meniscus in footballers with a stable knee is characterized by pain at the anterolateral aspect of the knee during knee extension, especially when kicking a ball, and pain during weight-bearing knee extension, together with MRI finding of hyperintense signal in the anterior horn of the lateral meniscus. Preoperative diagnosis may be possible based on these findings in footballers

Acute onset of intracranial subdural hemorrhage five days after spinal anesthesia for knee arthroscopic surgery: a case report

<p>Abstract</p> <p>Introduction</p> <p>Spinal anesthesia is a widely used general purpose anesthesia. However, serious complications, such as intracranial subdural hemorrhage, can rarely occur.</p> <p>Case presentation</p> <p>We report the case of a 73-year-old Japanese woman who had acute onset of intracranial subdural hemorrhage five days after spinal anesthesia for knee arthroscopic surgery.</p> <p>Conclusion</p> <p>This case highlights the need to pay attention to acute intracranial subdural hemorrhage as a complication after spinal anesthesia. If the headache persists even in a supine position or nausea occurs abruptly, computed tomography or magnetic resonance imaging of the brain should be conducted. An intracranial subdural hematoma may have a serious outcome and is an important differential diagnosis for headache after spinal anesthesia.</p

Determination of the optimal connector length to enhance stability of backbone‐circularized granulocyte colony‐stimulating factor

Improving protein stability is important for industrial applications, and one promising method for achieving this is backbone circularization. As connector length affects stability, predicting and elucidating a more stable connector length is necessary for development of the backbone circularization method. However, the relationship between connector length and protein stability has not been completely elucidated. Here, we determined the most stable connector length for granulocyte colony‐stimulating factor by changing one residue at a time to produce connector length variants and then measuring their thermal stability. Analysis of the local structures obtained from the predicted structures of the circularized variants revealed that an approach using helix length, dihedral backbone angle, and number of unbonded hydrogen bond donors and acceptors is suitable for identifying connector lengths with higher stability

Injury to infrapatellar branch of saphenous nerve in anterior cruciate ligament reconstruction using vertical skin incision for hamstring harvesting: risk factors and the influence of treatment outcome

Abstract Background Injury to the infrapatellar branch of the saphenous nerve (IPBSN) is a high-frequency complication in anterior cruciate ligament (ACL) reconstruction. We analyzed the risk factor of IPBSN injury in ACL reconstruction. Moreover, we investigated the influence on treatment outcome by this complication. Methods One hundred twenty-three patients who underwent ACL reconstruction using semitendinosus tendon graft were studied. Gender, age, BMI, and additional use of gracilis tendon were recorded. Treatment outcome was assessed by Lysholm score, visual analog scale (VAS) pain score, anterior knee pain, knee range of motion (ROM), and the patient-based SF-36. Patients who developed sensory disturbance at 24 months after reconstruction were compared with those without sensory disturbance. Results Twenty-six of 123 patients (21.1%) developed postoperative sensory disturbance caused by IPBSN injury. Baseline parameters were not significantly different compared to those in the non-sensory disturbance group. In the sensory disturbance group, treatment outcome evaluated at 24 months post-reconstruction showed Lysholm score of 94.1, VAS of 9.8 mm, anterior knee pain in 7.7%, and limitation of knee extension of 5° in 7.7%. SF-36 scores in all subscales were above the mean national standard scores. Treatment outcome parameters were also not significantly different compared to those in the non-sensory disturbance group, and none of the patients had serious impairment of knee function and activities of daily living. Conclusion Injury to IPBSN in ACL reconstruction was not related to age, gender, and physique, and injury frequency did not increase. Evaluation of postoperative treatment outcome showed that IPBSN injury was not related to anterior knee pain or knee ROM limitation, and patients’ subjective evaluation confirmed no serious impact on physical and mental health