Three-dimensional printed calcium phosphate scaffolds emulate bone microstructure to promote bone regrowth and repair.

The interconnected structures in a 3D scaffold allows the movement of cells and nutrients. Therefore, this study aimed to investigate the in-vivo bioactivity of 3D-printed ß-tricalcium phosphate (ß-TCP) and hydroxyapatite (HAP) scaffolds that replicate biological bone. This study included 24-week-old male New Zealand white rabbits. A cylindrical bone defect with a diameter of 4.5 mm and a depth of 8 mm was created in the lateral aspect of the distal femur. A 3D-printed scaffold was implanted in the right femur (experimental side), whereas the left femur was kept free of implantation (control side). Micro-CT analysis and histological observations of the bone defect site were conducted at 4, 8, and 12 weeks postoperatively to track the bone repair progress. No evidence of new bone tissue formation was found in the medullary cavity of the bone defect on the control side. In contrast, on the experimental side, the 3D scaffold demonstrated sufficient bioactivity, leading to the growth of new bone tissue. Over time, new bone tissue gradually extended from the periphery toward the center, a phenomenon evident in both micro-CT images and biopsy staining. In the current study, we observed that the cells involved in bone metabolism adhered, spread, and proliferated on our newly designed 3D-printed scaffold with a bone microstructure. Therefore, it is suggested that this scaffold has sufficient bioactivity to induce new bone formation and could be expected to be a more useful artificial bone than the existing version.

Systemic acylcarnitine levels are affected in response to multiple injuries and hemorrhagic shock: An analysis of lipidomic changes in a standardized porcine model.

INTRODUCTION: Along with recent advances in analytical technologies, tricarboxylic acid-cycle intermediates are increasingly identified as promising makers for cellular ischemia and mitochondrial dysfunction during hemorrhagic shock. For traumatized patients, the knowledge of the role of lipid oxidation substrates is sparse. In this study, we aimed to analyze the dynamics of systemic acylcarnitine (AcCa) release in a standardized polytrauma model with hemorrhagic shock. METHODS: Fifty-two male pigs (50 ± 5 kg) were randomized into two groups: group isolated fracture was subject to a standardized femur shaft fracture, and group polytrauma was subject to a femur fracture, followed by blunt chest trauma, liver laceration, and a pressure-controlled hemorrhagic shock for 60 minutes. Resuscitation was performed with crystalloids. Fractures were stabilized by intramedullary nailing. Venous samples were collected at six time points (baseline, trauma, resuscitation, 2 hours, 4 hours, and 6 hours). Lipidomic analysis was performed via liquid chromatography coupled mass spectrometry. Measurements were collated with clinical markers and near-infrared spectrometry measurements of tissue perfusion. Longitudinal analyses were performed with linear mixed models, and Spearman's correlations were calculated. A p value of 0.05 was defined as threshold for statistical significance. RESULTS: From a total of 303 distinct lipids, we identified two species of long-chain AcCas. Both showed a highly significant ( p < 0.001) twofold increase after hemorrhagic shock in group polytrauma that promptly normalized after resuscitation. This increase was associated with a significant decrease of the base excess ( p = 0.005), but recovery after resuscitation was faster. For both AcCas, there were significant correlations with decreased muscle tissue oxygen delivery ( p = 0.008, p = 0.003) and significant time-lagged correlations with the increase of creatine kinase ( p < 0.001, p < 0.001). CONCLUSION: Our results point to plasma AcCas as a possible indicator for mitochondrial dysfunction and cellular ischemia in hemorrhagic shock. The more rapid normalization after resuscitation in comparison with acid base changes may warrant further investigation.

Effects of high antibiotic concentrations applied to continuous local antibiotic perfusion on human bone tissue-derived cells.

Aims: Continuous local antibiotic perfusion (CLAP) has recently attracted attention as a new drug delivery system for orthopaedic infections. CLAP is a direct continuous infusion of high-concentration gentamicin (1,200 µg/ml) into the bone marrow. As it is a new system, its influence on the bone marrow is unknown. This study aimed to examine the effects of high-concentration antibiotics on human bone tissue-derived cells. Methods: Cells were isolated from the bone tissue grafts collected from six patients using the Reamer-Irrigator-Aspirator system, and exposed to different gentamicin concentrations. Live cells rate, apoptosis rate, alkaline phosphatase (ALP) activity, expression of osteoblast-related genes, mineralization potential, and restoration of cell viability and ALP activity were examined by in vitro studies. Results: The live cells rate (the ratio of total number of cells in the well plate to the absorbance-measured number of live cells) was significantly decreased at ≥ 500 µg/ml of gentamicin on day 14; apoptosis rate was significantly increased at ≥ 750 µg/ml, and ALP activity was significantly decreased at ≥ 750 µg/ml. Real-time reverse transcription-polymerase chain reaction results showed no significant decrease in the ALP and activating transcription factor 4 transcript levels at ≥ 1,000 µg/ml on day 7. Mineralization potential was significantly decreased at all concentrations. Restoration of cell viability was significantly decreased at 750 and 1,000 µg/ml on day 21 and at 500 µg/ml on day 28, and ALP activity was significantly decreased at 500 µg/ml on day 28. Conclusion: Our findings suggest that the exposure concentration and duration of antibiotic administration during CLAP could affect cell functions. However, further in vivo studies are needed to determine the optimal dose in a clinical setting.

Complications including dysphagia following transoral non-robotic surgery for pharyngeal and laryngeal squamous cell carcinoma: A retrospective multicenter study.

OBJECTIVE: Transoral surgery is a minimally invasive treatment but may cause severe dysphagia at a lower rate than chemoradiotherapy. METHODS: We compared clinical information, surgical complications, and swallowing function in patients who underwent transoral nonrobotic surgery for laryngo-pharyngeal squamous cell carcinoma between 2015 and 2021 in a multicenter retrospective study. RESULTS: Six hundred and forty patients were included. Postoperative bleeding was observed in 20 cases (3.1%), and the risk factor was advanced T category. Postoperative laryngeal edema was observed in 13 cases (2.0%), and the risk factors were prior radiotherapy, advanced T stage, and concurrent neck dissection in patients with resected HPC. Dysphagia requiring nutritional support was observed in 29 cases (4.5%) at 1 month postoperatively and in 19 cases (3.0%) at 1 year postoperatively, respectively. The risk factors for long-term dysphagia were prior radiotherapy and advanced T category. Short-term risk factors for dysphagia were prior radiotherapy, advanced T category, and concurrent neck dissection, while long-term risk factors for dysphagia were only prior radiotherapy and advanced T category. CONCLUSION: Prior radiotherapy, advanced T stage, and concurrent neck dissection increased the incidence of postoperative laryngeal edema and short-term dysphagia, but concurrent neck dissection did not affect long-term dysphagia. Such features should be considered when considering the indication for transoral surgery and postoperative management.

Mucosal melanoma of the head and neck: a retrospective analysis of 34 cases in Japan.

PURPOSE: Mucosal melanoma of the head and neck (MMHN) is a rare condition. This study aimed to investigate oncological outcomes of surgical intervention in patients with MMHN. MATERIALS AND METHODS: The study included 34 patients with MMHN who underwent surgical resection as initial treatment at 10 institutions in Japan between July 2005 and June 2015. Results: The 5-year overall survival (OS), local control rate (LCR), disease-free survival (DFS), and disease-specific survival (DSS) rates were 48.7%, 53.4%, 32.4%, and 55.1%, respectively. Based on multivariate analysis, no independent prognostic factors for the 5-year OS and DSS were found. Based on univariate analysis, the 5-year LCR was worse in patients with lesions in the nasal cavity and paranasal sinuses than in the oral cavity and pharynx. However, no differences in oncological outcomes were identified in relation to primary sites, and postoperative radiotherapy (PORT) and adjuvant systemic therapy did not contribute to improvements in the 5-year OS. CONCLUSIONS: No independent prognostic factors for the 5-year OS or DSS were identified. Regional or distant recurrences are often identified, regardless of local control with surgical resection. Difficult control of MMHN with conventional therapeutic strategies, such as surgical intervention, PORT, and systemic therapy, has been suggested.

Impact of cervical lymph node metastasis on transoral surgery for hypopharyngeal squamous cell carcinoma: A retrospective multicenter study.

BACKGROUND: Hypopharyngeal carcinoma is likely to spread to the lymph nodes, but there is no established strategy for management in transoral surgery. METHODS: We compared oncologic and functional outcomes in a retrospective multicenter study of patients who underwent transoral surgery for hypopharyngeal carcinoma between 2015 and 2021. RESULTS: Two-hundred and thirty-two patients were included. Comparing patients with and without adjuvant radiotherapy, 3-year regional recurrence-free survival (RRFS) was not significantly different in pN2b and pN2c, but was significantly worse in pN3b without adjuvant radiotherapy. In patients without neck dissection, the 3-year RRFS was 85.6%, 76.8%, and 70.0% for T1, T2, and T3 primary lesions, respectively, and was significantly worse for T2 or higher (p = 0.035). CONCLUSIONS: In the absence of extracapsular invasion, regional control did not deteriorate without adjuvant therapy. If prophylactic neck dissection is not performed, careful follow-up is necessary if the primary lesion is T2 or greater.

A multi-institutional retrospective study of 340 cases of sinonasal malignant tumor.

OBJECTIVE: Sinonasal malignant tumors (SNMT) are relatively rare among head and neck malignant tumors. Most are squamous cell carcinomas, and malignant melanomas, olfactory neuroblastomas, adenoid cystic carcinomas, sarcomas, and others also occur. The most common primary site of nasal sinus squamous cell carcinoma is the maxillary sinus. In recent years, a decrease in incidence of maxillary sinus squamous cell carcinoma (MSSCC) has been reported along with a decrease in the incidence of sinusitis. MSSCC is treated with a combination of surgery, radiation, and chemotherapy. Treatment decisions are made according to the progression of the disease, the patient's general condition, and the patient's own wishes. There are variations in treatment policies among facilities due to the specialty of staff and cooperation with other departments at each facility. We conducted a multi-institutional retrospective study to compare outcomes by treatment strategy. METHODS: In this study, 340 patients with SNMT who were treated at 13 Hospitals (Head and Neck Oncology Group (Kyoto-HNOG) ) during the 12-year period from January 2006 to December 2017 were included. There were 220 patients with squamous cell carcinoma, 32 with malignant melanoma, 21 with olfactory neuroblastoma, and 67 with other malignancies. Of the squamous cell carcinomas, 164 were of maxillary sinus origin. One hundred and forty cases of MSSCC that were treated radically were included in the detailed statistical analysis. RESULTS: There were 5 cases of cStage I, 9 cases of cStage II, 36 cases of cStage III, 74 cases of cStage IVa, and 16 cases of cStage IVb. There were 92 cases without clinical lymph node metastasis (cN(-)) and 48 cases with clinical lymph node metastasis(cN(+)). Primary tumors were treated mainly by surgery in 85 cases (Surg) and by radical radiation therapy (with or without chemotherapy) of 6-70 Gy in 55 cases(non-Surg). The 5-year overall/disease-free survival rate (OS/DFS) for MSSCC was 65.1%/51.6%. Old age, renal dysfunction, and clinical T progression were independent risk factors for OS, and renal dysfunction was an independent risk factor for DFS. In cN(-) patients, OS and DFS were significantly better in Surg group than in non-Surg group. In cN(+) patients, there was no significant difference in OS and DFS between Surg and non-Surg groups. CONCLUSION: For patients with MSSCC without lymph node metastasis, aggressive surgery on the primary tumor contributes to improved prognosis.

Local recurrence and metachronous multiple cancers after transoral nonrobotic surgery for pharyngeal and laryngeal squamous cell carcinoma: A retrospective multicenter study.

BACKGROUND: Late laryngopharyngeal cancers after transoral surgery include not only local recurrences but also metachronous multiple cancers. METHODS: We compared clinical information, surgical outcomes, and late laryngopharyngeal cancers in patients who underwent transoral nonrobotic surgery for laryngopharyngeal squamous cell carcinoma without lymph node metastases between 2015 and 2021 in a multicenter retrospective study. RESULTS: Four hundred and fifty-seven patients were included. Positive surgical margins were found in 121 patients (26.5%). Twenty-two patients (4.8%) received additional treatment. Positive horizontal margins of invasive carcinoma (p = 0.003) and positive horizontal margins of carcinoma in situ only (p = 0.032) were independent risk factors for local recurrence, and prior radiotherapy (p = 0.001) for metachronous multiple cancers. Local control was significantly worse without additional treatment (p = 0.049), but there was no significant difference in survival. CONCLUSIONS: Patients with positive margins had an increased frequency of local recurrence, but salvage therapy was effective.

Parathyroid carcinoma: impact of preoperative diagnosis on the choice of surgical procedure.

The operative procedure in the surgical treatment of parathyroid carcinoma differs from that of benign hyperparathyroidism. However, preoperative differentiation is often difficult. This study elucidated how clinicians diagnose parathyroid carcinoma and the relationship between preoperative diagnosis and the operative course. Using a retrospective chart review, twenty cases of parathyroid carcinoma from nine participating centers were examined. In 11 cases with preoperative suspicion of malignancy, at least one of these three features was found: elevated serum calcium level (>14 mg/dL), palpable mass, and irregular margin on ultrasonography. Although an intact parathyroid hormone (iPTH) threshold to suspect malignancy has not been established, six cases showed marked iPTH elevation exceeding 8.0 times the upper limit of normal. One case was excluded from analysis due to hemodialysis. Compared with the four cases that showed calcium elevation, the iPTH threshold might represent better sensitivity. Among 9 cases of benign preoperative diagnosis, six cases were performed with pericapsular resection. In three cases where malignancy was suspected in the middle of the operation, the recommended en bloc resection with ipsilateral thyroid lobectomy was not performed but a parathyroidectomy with surrounding soft tissue. In contrast, 10 preoperatively suspected cases underwent en bloc resection, and one case underwent pericapsular resection followed by supplementary ipsilateral hemithyroidectomy due to the uncertain pre- and intraoperative findings to determine the diagnosis. In conclusion, the surgical procedure for parathyroid carcinoma strongly depends on the preoperative diagnosis. The presence of excessive iPTH levels might contribute to improved preoperative diagnostic sensitivity for parathyroid carcinoma.

Characteristics of oral squamous cell carcinoma focusing on cases unaffected by smoking and drinking: A multicenter retrospective study.

BACKGROUND: Some oral squamous cell carcinoma (OSCC) cases are unaffected by smoking or drinking. This study aimed to clarify distinctive groups among OSCC patients and examine the characteristics of multiple primary carcinomas (MPCs). METHODS: We analyzed data from 970 patients. The patients were divided into three groups: all individuals <45 years (<45 y), smokers/drinkers ≥45 years (SD ≥45 y), and non-smokers/non-drinkers ≥45 years (NSND ≥45 y). RESULTS: Tongue cancers were more common in the <45 y group than in the other groups (p < 0.001). The NSND ≥45 y group was significantly older and more likely to be female than the SD ≥45 y group (p < 0.001). MPCs in the upper aerodigestive tract were more common in men and smokers/drinkers, whereas women were at risk for multiple primary OSCCs (p = 0.022). CONCLUSIONS: The "young tongue" and "elderly female" subgroups and characteristics of MPCs suggest carcinogenic factors of OSCC other than smoking and drinking.

Surgical load in major fractures - results of a survey on the optimal quantification and timing of surgery in polytraumatized patients.

PURPOSE: It is known that the magnitude of surgery and timing of surgical procedures represents a crucial step of care in polytraumatized patients. In contrast, it is not clear which specific factors are most critical when evaluating the surgical load (physiologic burden to the patient incurred by surgical procedures). Additionally, there is a dearth of evidence for which body region and surgical procedures are associated with high surgical burden. The aim of this study was to identify key factors and quantify the surgical load for different types of fracture fixation in multiple anatomic regions. METHODS: A standardized questionnaire was developed by experts from Société Internationale de Chirurgie Orthopédique et de Traumatologie (SICOT)-Trauma committee. Questions included relevance and composition of the surgical load, operational staging criteria, and stratification of operation procedures in different anatomic regions. Quantitative values according to a five-point Likert scale were chosen by the correspondents to determine the surgical load value based on their expertise. The surgical load for different surgical procedures in different body regions could be chosen in a range between "1," defined as the surgical load equivalent to external (monolateral) fixator application, and "5," defined as the maximal surgical load possible in that specific anatomic region. RESULTS: This questionnaire was completed online by 196 trauma surgeons from 61 countries in between Jun 26, 2022, and July 16, 2022 that are members of SICOT. The surgical load (SL) overall was considered very important by 77.0% of correspondents and important by 20.9% correspondents. Intraoperative blood loss (43.2%) and soft tissue damage (29.6%) were chosen as the most significant factors by participating surgeons. The decision for staged procedures was dictated by involved body region (56.1%), followed by bleeding risk (18.9%) and fracture complexity (9.2%). Percutaneous or intramedullary procedures as well as fractures in distal anatomic regions, such as hands, ankles, and feet, were consistently ranked lower in their surgical load. CONCLUSION: This study demonstrates a consensus in the trauma community about the crucial relevance of the surgical load in polytrauma care. The surgical load is ranked higher with increased intraoperative bleeding and greater soft tissue damage/extent of surgical approach and depends relevantly on the anatomic region and kind of operative procedure. The experts especially consider anatomic regions and the risk of intraoperative bleeding as well as fracture complexity to guide staging protocols. Specialized guidance and teaching is required to assess both the patient's physiological status and the estimated surgical load reliably in the preoperative decision-making and operative staging.

Developments in the understanding of staging a "major fracture" in polytrauma: results from an initiative by the polytrauma section of ESTES.

PURPOSE: Although the term "major fracture" is commonly used in the management of trauma patients, it is defined insufficiently to date. The polytrauma section of ESTES is trying to develop a more standardized use and a definition of the term. In this process, a standardized literature search was undertaken. We test the hypothesis that the understanding of "major fractures" has changed and is modified by a better understanding of patient physiology. METHODS: A systematic literature search of the Medline and EMBASE databases was conducted in March 2022. Original studies that investigated surgical treatment strategies in polytraumatized patients with fractures were included: This included timing, sequence and type of operative treatment. A qualitative synthesis regarding the prevalence of anatomic regions of interest and core factors determining decision-making was performed. Data were stratified by decades. RESULTS: 4278 articles were identified. Of these, 74 were included for qualitative evaluation: 50 articles focused on one anatomic region, 24 investigated the relevance of multiple anatomic regions. Femur fractures were investigated most frequently (62) followed by pelvic (22), spinal (15) and tibial (15) fractures. Only femur (40), pelvic (5) and spinal (5) fractures were investigated in articles with one anatomic region of interest. Before 2010, most articles focused on long bone injuries. After 2010, fractures of pelvis and spine were cited more frequently. Additional determining factors for decision-making were covered in 67 studies. These included chest injuries (42), TBI (26), hemorrhagic shock (25) and other injury-specific factors (23). Articles before 2000 almost exclusively focused on chest injury and TBI, while shock and injury-specific factors (e.g., soft tissues, spinal cord injury, and abdominal trauma) became more relevant after 2000. CONCLUSION: Over time, the way "major fractures" influenced surgical treatment strategies has changed notably. While femur fractures have long been the only focus, fixation of pelvic and spinal fractures have become more important over the last decade. In addition to the fracture location, associated conditions and injuries (chest trauma and head injuries) influence surgical decision-making as well. Hemodynamic stability and injury-specific factors (soft tissue injuries) have increased in importance over time.

Post-traumatic growth in polytraumatized patients after 20+ years: a long-term follow-up study of 337 patients treated at a level 1 trauma center.

PURPOSE: There is limited research on the long-term psychiatric outcomes of polytraumatized patients. Existing studies focus mainly on the negative sequelae. Post-traumatic growth (PTG) describes positive personal development after severe physical or mental distress. In this study, we investigated post-traumatic growth in polytraumatized patients at least 20 years after trauma. METHODS: Patients treated for polytrauma at a German level 1 trauma center between 1971 and 1990, were contacted 20+ years later. A questionnaire with 37 questions from the stress-related growth scale (SRGS) and the post-traumatic growth inventory (PGI) was administered. PTG was quantified in five specific areas. PTG and patient demographics were then analyzed using logistic regression. RESULTS: Eligible questionnaires were returned by 337 patients. 96.5% of patients reported improvements regarding at least one of the 37 questions. Approximately, a third of patients noticed distinct improvements regarding their relationship to others (29.2%), appreciation of life (36.2%) and attitudes towards new possibilities (32.5%). Patient demographics were significant predictors for the development of PTG: Older (p < 0.001), female (p = 0.042) and married patients (p = 0.047) showed a greater expression of PTG. We also saw significantly more PTG in patients with higher injury severity (p = 0.033). CONCLUSION: 20 years after polytrauma, patients report improvements in their relationship with others, appreciation of life and attitude towards new possibilities. Women and married patients show higher expression of PTG. Furthermore, there is higher expression of PTG with higher age and injury severity. Post-traumatic growth should be identified and fostered in clinical practice. LEVEL OF EVIDENCE: III-prospective long-term follow-up study.

Human Non-Hypertrophic Nonunion Tissue Contains Osteoblast Lineage Cells and E-BMP-2 Activates Osteogenic and Chondrogenic Differentiation.

In this study, we examined the proliferation capability and osteogenic and chondrogenic differentiation potential of non-hypertrophic nonunion cells (NHNCs), and the effect of Escherichia coli-derived BMP-2 (E-BMP-2) on them. We enrolled five patients with non-hypertrophic nonunion. NHNCs isolated from nonunion tissue sampled during surgery were cultured, passaged, counted every 14 days, and analyzed. NHNCs were homogenous fibroblastic adherent cells and long-lived through at least 10 passages, with a slight decline. The cells were consistently positive for mesenchymal stem cell-related markers CD73 and CD105, and negative for the hematopoietic markers CD14 and CD45. NHNCs could differentiate into osteoblast lineage cells; however, they did not have strong calcification or sufficient chondrogenic differentiation capability. E-BMP-2 did not affect the proliferative capability of the cells but improved their osteogenic differentiation capability by increasing alkaline phosphatase activity and upregulating the gene expression of osterix, bone sialoprotein, and osteocalcin. E-BMP-2 enhanced their chondrogenic differentiation capability by upregulating the gene expression of aggrecan and collagen type II. We showed, for the first time, that NHNCs have the capacity to differentiate into osteoblast-lineage cells, although the chondrogenic differentiation potential was poor. Local application of E-BMP-2 with preservation of nonunion tissue is a potential treatment option for non-hypertrophic nonunion.

Fat embolism syndrome in patients with bilateral femur fractures: a systematic review and case comparison.

Objectives: Fat embolism and fat embolism syndrome (FES) remain common complications following long bone fractures. Incidence is highest after bilateral femur fractures. We performed a systematic review of FES after bilateral femur fractures and present two cases. Data sources: Systematic literature search of the Cochrane, EMBASE, MEDLINE, Scopus, and, Web of Science Library databases was performed in August 2021. Terms used including plural and alternate spellings: "fat embolism,""fat embolism syndrome,""fat embolus," and "bilateral femur fracture." Articles in German and English were considered. No time frame was applied. Study selection: Original studies, case series and case reports on fat embolism after bilateral femur fracture were included. Insufficient documentation or patients with relevant previous heath conditions were excluded. Data extraction: Abstracts were organized using EndNote X9 by Carivate. Three authors independently screened the abstracts; cross check of the extracted data was performed by the senior author. Data synthesis: Scarcity of articles only allowed for a qualitative synthesis. Data was compared with our cases and situated within the scientific background. Results: Ten articles were included for qualitative synthesis (n = 144 patients). The symptoms were inhomogeneous with neurological deficits being most prominent. Degree of displacement was high, when reported. Although the modes and timing of surgery varied, this appeared unrelated with outcome. Conclusions: FES remains a relevant complication after bilateral femur fractures, despite damage control strategies and improved reaming techniques. Fracture displacement and reduction maneuvers might play a more substantial role in the formation than previously accredited. Level of evidence: 4.

Occult hypoperfusion and changes of systemic lipid levels after severe trauma: an analysis in a standardized porcine polytrauma model.

BACKGROUND: Occult hypoperfusion describes the absence of sufficient microcirculation despite normal vital signs. It is known to be associated with prolonged elevation of serum lactate and later complications in severely injured patients. We hypothesized that changes in circulating lipids are related to responsiveness to resuscitation. The purpose of this study is investigating the relation between responsiveness to resuscitation and lipidomic course after poly trauma. METHODS: Twenty-five male pigs were exposed a combined injury of blunt chest trauma, liver laceration, controlled haemorrhagic shock, and femoral shaft fracture. After 1 h, animals received resuscitation and fracture stabilization. Venous blood was taken regularly and 233 specific lipids were analysed. Animals were divided into two groups based on serum lactate level at the end point as an indicator of responsiveness to resuscitation (<2 mmol/L: responder group (R group), ≧2 mmol/L: occult hypoperfusion group (OH group)). RESULTS: Eighteen animals met criteria for the R group, four animals for the OH group, and three animals died. Acylcarnitines showed a significant increase at 1 h compared to baseline in both groups. Six lipid subgroups showed a significant increase only in R group at 2 h. There was no significant change at other time points. CONCLUSIONS: Six lipid groups increased significantly only in the R group at 2 h, which may support the idea that they could serve as potential biomarkers to help us to detect the presence of occult hypoperfusion and insufficient resuscitation. We feel that further study is required to confirm the role and mechanism of lipid changes after trauma.

Safety of 222 nm UVC Irradiation to the Surgical Site in a Rabbit Model.

For the prevention of surgical site infection (SSI), continuous disinfection could be helpful. Short wavelength ultraviolet radiation C (UVC) is highly bactericidal but shows cytotoxicity. Radiation of UVC with a wavelength of 222 nm to the skin is considered to be safe because it only reaches the stratum corneum. However, the safety of 222 nm irradiation to the surgical field not covered with skin is unknown. The purpose of this study was to examine the safety of 222 nm UVC irradiation on a surgical field in a rabbit model. Five types of tissue were surgically exposed and irradiated with 222 or 254 nm UVC. Immunohistological assessment against cyclobutane pyrimidine dimer (CPD), an index of DNA damage by UVC, was performed. The CPD-positive cell rate was significantly higher in the 254 nm group than in the other groups in all tissues. A 222 nm group showed significantly more CPD than control in fat tissue, but no significant difference in all other tissues. In fat tissue collected 24 h after irradiation, the 254 nm group showed higher CPD than the other groups, while the 222 nm group had reduced to the control level. These data suggest that 222 nm UVC irradiation could be a new method to safely prevent SSI.

Real-world 2-year long-term outcomes and prognostic factors in patients receiving nivolumab therapy for recurrent or metastatic squamous cell carcinoma of the head and neck.

OBJECTIVE: Real-world outcomes and prognostic factors in Japanese patients receiving nivolumab therapy for recurrent or metastatic head and neck carcinoma (RMHNC) with an observation period of 1 year have been previously reported. The 1-year follow-up data have been subsequently accumulated, and the long-term real-world outcomes have been analyzed. This study aimed to investigate the 2-year long-term outcomes and prognostic factors associated with the response to nivolumab. METHODS: This was a multi-institutional retrospective study. In total, 88 RMHNC Japanese patients with squamous cell carcinoma who received nivolumab between May 2017 and May 2018 were retrospectively reviewed. Overall survival (OS), progression-free survival (PFS), and best overall response (BOR) were evaluated. Univariate and multivariable analyses were performed to identify the prognostic factors. RESULTS: The median follow-up periods for monitoring OS and PFS were 73.1 and 48.1 weeks, respectively. The median OS was 74.1 weeks, and the 2-year survival rate was 33.4%. The median PFS was 18.5 weeks, and the 2-year PFS rate was 22.5%. The BOR rate was 10.2%, 19.3%, 25.0%, and 44.3% in patients who achieved complete response, partial response, stable disease, and progressive disease (PD), respectively. Among the 88 patients with RMHNC, a total of 40 immune-related adverse events (irAEs) were reported in 30 patients. Four patients continued nivolumab, while 84 patients discontinued nivolumab at the data cut-off date. The most common reason for discontinuation was PD in 61 patients, irAEs in 14 patients, and patients' wishes in 7 patients. Of the 61 patients who discontinued nivolumab because of PD, 28 patients received subsequent treatment. Statistical analyses revealed radiotherapy history, performance status, platinum-refractory carcinoma, irAEs, age, and post-nivolumab treatment as the important prognostic factors associated with OS in patients with RMHNC, and the magnitude of BOR was significantly associated with OS. Additionally, patients with subsequent treatment, including molecular targeted therapy and/or chemotherapy, had significantly prolonged OS compared to patients without subsequent treatment in cases with nivolumab discontinuation because of PD. CONCLUSION: These findings could be a useful guide for future treatment strategies for head and neck carcinoma. Considering the limitations of our cohort, further larger-scale studies with long-term follow-up are needed to substantiate the results of this study.

Low-Intensity Pulsed Ultrasound Promotes Osteogenic Differentiation of Reamer-Irrigator-Aspirator Graft-Derived Cells in Vitro.

Recently, reamer-irrigator-aspirator (RIA) systems have been increasingly used to harvest autologous bone grafts. RIA graft materials contain bone marrow, which provides a viable source to derive large numbers of mesenchymal stem cells. Low-intensity pulsed ultrasound (LIPUS) significantly accelerates the differentiation of stem cells derived from bone marrow. This in vitro study investigated the effect of LIPUS on the osteogenic activity and differentiation of RIA graft-derived cells. A small amount of RIA graft was obtained from seven patients. After the cells derived from RIA grafts were cultured, they were divided into two groups: the LIPUS and control groups. LIPUS was applied once daily for 20 min (1.5 MHz, pulse duration: 200 µs, pulse repetition rate: 1 kHz, spatial average-temporal average intensity: 30 mW/cm2). Alkaline phosphatase activity (113.4% and 130.1% on days 7 and 14), expression of osteoblast-related genes (ALP, Runx2) and mineralization (135.2% on day 21) of the RIA graft-derived cells were significantly higher in the LIPUS group than in the control group. However, LIPUS did not affect the cell proliferation of RIA graft-derived cells. This study indicates that LIPUS may enhance the healing of non-union and critical bone defects treated by autologous bone grafting using the RIA system.

Clinicopathological Characteristics and Survival Outcomes of Patients with Buccal Squamous Cell Carcinoma: Results of a Multi-Institutional Study.

Background and Objectives: To investigate clinicopathological characteristics and survival outcomes of patients with buccal cancer in Japan. Materials and Methods: This study was conducted using a database of 1055 patients with oral cancers treated between 2010 and 2017 at 12 institutions in Japan. Ninety-two patients (8.7%) with primary buccal cancer were extracted and clinicopathological characteristics and survival outcomes were compared between patients with buccal cancers and patients with other oral cancers. Results: Ages were significantly higher in the patients with buccal cancer (73 years old vs. 69 years old). Buccal cancer had less advanced cT stage and cN stage than other oral cancers. Overall 5-year survival (OS) was 80.6%, and recurrence-free 5-year survival (RFS) of buccal cancers was 67.8%, and there were no significant differences in survival compared with other oral cancers in terms OS or RFS (5y-OS: 82.5%, 5y-RFS: 74.4%). However, patients with stage IV buccal cancer showed poorer prognosis in terms of OS and RFS compared with the same stage patients with other oral cancer. Advanced T stage was the only factor independently associated with both OS and RFS of patients with buccal cancer in this study. Conclusions: Postoperative radiotherapy or chemoradiotherapy should be considered to improve survival outcome of buccal cancer patients, especially for the patients with advanced primary site disease or a higher cancer stage.