A simple and static preservation system for shipping retinal pigment epithelium cell sheets

The ability to move cells and tissues from bench to bedside is an essential aspect of regenerative medicine. In this study, we propose a simple and static shipping system to deliver tissue-engineered cell sheets. Notably, this system is electronic-device-free and simplified to minimize the number of packing and opening steps involved. Shipping conditions were optimized, and application and verification of the system were performed using human iPS cell-derived or fetal retinal pigment epithelium (RPE) cell sheets. The temperature of the compartments within the insulated container was stable at various conditions, and filling up the cell vessel with medium effectively prevented turbulence-induced mechanical damage to the RPE cell sheets. Furthermore, no abnormal changes were observed in RPE morphology, transepithelial electrical resistance, or mRNA expression after transit by train and car. Taken together, our simple shipping system has the potential to minimize the costs and human error associated with bench to bedside tissue transfer. This specially designed regenerative tissue shipping system, validated for use in this field, can be used without any special training. This study provides a procedure for easily sharing engineered tissues with the goal of promoting collaboration between laboratories and hospitals and enhancing patient care.

Migration of a Kirschner wire into the spinal cord: A case report and literature review

CONTEXT

A Kirschner wire (K-wire) is a stainless steel pin with at least one sharpened tip that is mainly used for the internal fixation of bone fractures. While some cases of K-wire dislocation and migration have been reported as complications after fracture surgery, the intraspinal migration of a K-wire is rare. Herein, we report a case in which a K-wire used for sternal fixation 7 years earlier migrated into the spinal canal.

FINDINGS

A 68-year-old male suddenly sustained severe radiating pain and numbness in his left upper extremity, and walked to our hospital. He had mild weakness in the left wrist extensor muscles and the left extensor digitorum. CT-myelography revealed a K-wire penetrating into the spinal cord at C5-6. There was no injury of the trachea, esophagus, or blood vessels. The patient had a history of surgical infection after cardiovascular surgery seven years before, and had undergone surgical debridement and sternum fixation with two K-wires. One K-wire had broken, and part of it migrated upward. Using an anterior approach, we detected the tip of K-wire below the left sternocleidomastoid muscle. We cut the K-wire into 1 to 2-cm pieces and removed it piece by piece. His postoperative course was uneventful and the symptoms improved markedly after the surgery.

CONCLUSION

This is the first report of a K-wire that had been used for sternal fixation migrating into the spinal cord. This case illustrates that although rare, it is possible for a K-wire to migrate upward after sternal fixation.

Position of the major curve influences asymmetrical trunk kinematics during gait in adolescent idiopathic scoliosis

BACKGROUND AND PURPOSE

Adolescent idiopathic scoliosis (AIS) is a structural, lateral curvature with rotation of the spine that develops around puberty. The influence of this spinal deformity on three-dimensional trunk movements during gait has not yet been elucidated. The aim of this study was to determine the influence of spinal curve pattern (single thoracic curve vs. single lumbar curve) on trunk kinematics during gait.

METHODS

Twenty-two patients with a single thoracic curve (Lenke type 1) and 17 patients with a single lumbar curve (Lenke type 5) were included in this study. Trunk symmetry in the sagittal, coronal, and transverse planes during gait was evaluated using an optoelectronic motion capture system.

RESULTS

In the type 1 group, the trunk was significantly rotated towards the concave side in the transverse plane during gait (mean difference of transverse rotation angle between concave side load and the convex side load, 8.8±0.6°, p<0.01). In the type 5 group, the trunk was significantly rotated towards the convex side in the coronal plane throughout the stance phase of gait (mean difference of coronal inclination angle, 1.9±0.3°, p<0.05).

CONCLUSIONS

The AIS patients with a single thoracic curve showed asymmetrical trunk movement in the transverse plane, and patients with a single lumbar curve showed asymmetrical trunk movement in the coronal plane. These results indicate that the spinal curve pattern influenced trunk kinematics, and suggest that the global postural control strategy of patients with AIS differs according to the curve pattern.

Polymorphisms in PTCH1 Affect the Risk of Ameloblastoma

Ameloblastoma is the most common odontogenic tumor, but the genetic nature of the changes in the tumor cells has been unclear. Mutations of CTNNB1 or PTCH1 are observed in many human tumors. Both CTNNB1 and PTCH1 are important in tooth development and are expressed in ameloblastoma. The aim of this study was to investigate whether genetic alterations of CTNNB1 and PTCH1 are present in ameloblastoma. We investigated 14 cases of ameloblastoma. The polymorphisms found in the ameloblastoma patients were further examined in a subsequent case-control study. We found a CTNNB1 mutation in one case of plexiform-type ameloblastoma. CGG triplet repeat-number polymorphism (CGG7/CGG8) in the 5′-untranslated region of PTCH1 was observed. The proportion of CGG8 alleles was significantly higher in the ameloblastoma group. The results of this study indicate a possible relationship between the CGG8 allele in PTCH1 and the risk for ameloblastoma.

Short-term outcomes of robotic radical esophagectomy for esophageal cancer by a nontransthoracic approach compared with conventional transthoracic surgery

Transthoracic esophagectomy (TTE) is believed to have advantages for mediastinal lymphadenectomy in the treatment of resectable esophageal cancer despite its association with a greater incidence of pulmonary complications and postoperative mortality. Transhiatal esophagectomy is regarded as less invasive, though insufficient in terms of lymph node dissection. With the aim of achieving lymph dissection equivalent to that of TTE, we have developed a nontransthoracic esophagectomy (NTTE) procedure combining a video-assisted cervical approach for the upper mediastinum and a robot-assisted transhiatal approach for the middle and lower mediastinum. We prospectively studied 22 accumulated cases of NTTE and verified feasibility by analyzing perioperative and histopathological outcomes. We compared this group's short-term outcomes with outcomes of 139 equivalent esophageal cancer cases operated on at our institution by conventional TTE (TTE group). In the NTTE group, there were no procedure-related events and no midway conversions to the conventional surgery; the mean operation time was longer (median, 524 vs. 428 minutes); estimated blood loss did not differ significantly between the two groups (median, 385 mL vs. 490 mL); in the NTTE group, the postoperative hospital stay was shorter (median, 18 days vs. 24 days). No postoperative pneumonia occurred in the NTTE group. The frequencies of other major postoperative complications did not differ significantly, nor were there differences in the numbers of harvested mediastinal lymph nodes (median, 30 vs. 29) or in other histopathology findings. NTTE offers a new radical procedure for resection of esophageal cancer combining a cervical video-assisted approach and a transhiatal robotic approach. Although further accumulation of surgical cases is needed to corroborate these results, NTTE promises better prevention of pulmonary complications in the management of esophageal cancer.

Biodegradable shape memory polymers functionalized with anti-biofouling interpenetrating polymer networks

A novel type of shape memory polyurethane (SMPU) with high mechanical properties and biodegradability was constructed using a lactone copolymer (poly(ε-caprolactone-co-γ-butyrolactone), PCLBL), a diol- or triol-based chain extender (1,5-pentanediol, glycerol and 2-amino-2-hydroxymethyl-1,3-propanediol) and a diisocyanate cross-linker (1,6-hexamethylene diisocyanate).