Observation of spin-glass-like characteristics in ferrimagnetic TbCo through energy-level-selective approach.

Rare earth (RE)-transition metal (TM) ferrimagnetic alloys are gaining increasing attention because of their potential use in the field of antiferromagnetic spintronics. The moment from RE sub-lattice primarily originates from the 4f-electrons located far below the Fermi level (EF), and the moment from TM sub-lattice arises from the 3d-electrons across the EF. Therefore, the individual magnetic moment configurations at different energy levels must be explored to clarify the microscopic mechanism of antiferromagnetic spin dynamics. Considering these issues, here we investigate the energy-level-selective magnetic moment configuration in ferrimagnetic TbCo alloy. We reveal that magnetic moments at deeper energy levels are more easily altered by the external magnetic field than those near the EF. More importantly, we find that the magnetic moments at deeper energy levels exhibit a spin-glass-like characteristics such as slow dynamics and magnetic moment freezing whereas those at EF do not. These unique energy-level-dependent characteristics of RE-TM ferrimagnet may provide a better understanding of ferrimagnet, which could be useful in spintronic applications as well as in spin-glass studies.

Importance of firm isthmic fixation in high-energy induced subtrochanteric fracture of the femur: retrospective observational study in a level I trauma center.

INTRODUCTION: This study aimed to report the surgical outcomes in patients with high-energy induced subtrochanteric fracture and determine the risk factors for nonunion using statistical analysis. METHODS: This study evaluated 88 patients with high-energy induced subtrochanteric fractures who underwent surgeries with indirect reduction technique and intramedullary nailing between March 2015 and December 2020. Outcome measures, including union time and nonunion incidence, were assessed by radiologic evaluation. Multiple logistic regression analyses were performed to identify the risk factors for nonunion, using age, sex, injury severity score, body mass index, preoperative mobility score, implant, and isthmic fixation as covariates. RESULTS: Five nonunions and two delayed unions were identified. The average union time was 17.4 weeks. Multiple logistic regression analyses showed that poor isthmic fixation was the only risk factor for nonunion (odds ratio 15.294, 95% confidence interval 1.603-145.894, P value 0.018). Out of five nonunion cases, four were confirmed as hypertrophic, and one was confirmed as atrophic. CONCLUSION: Although surgical treatment using an indirect reduction technique and intramedullary nailing showed good outcomes, hypertrophic nonunion due to distal instability could occur if a firm fixation at the level of the isthmus cannot be achieved. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Clinical Outcomes of Conversion Surgery after Neoadjuvant Chemotherapy in Patients with Borderline Resectable and Locally Advanced Unresectable Pancreatic Cancer: A Single-Center, Retrospective Analysis.

The clinical benefit and potential risks of conversion surgery after neoadjuvant chemotherapy (NACT) have not been fully investigated in patients with borderline resectable pancreatic cancer (BRPC) and locally advanced unresectable pancreatic cancer (LAPC). Therefore, this has been evaluated in a retrospective, prospective cohort-based analysis. Between October 2005 and April 2017, 135 patients (65 with BRPC and 70 with LAPC) received conversion surgery after NACT. Exploratory analysis to assess clinical outcomes in comparison with patients who underwent upfront surgery in the same time period (n = 359) was also conducted. NACT with gemcitabine-based regimens (including gemcitabine monotherapy, gemcitabine-capecitabine combination, and gemcitabine-erlotinib combination) was used in 69 patients (51%) and FOLFIRINOX in 66 patients (49%). The median overall survival (OS) and disease-free survival (DFS) from the time of surgery was 25.4 months (95% CI, 18.6⁻32.2 months) and 9.0 months (95% CI, 6.8⁻11.2 months), respectively. The median OS and progression-free survival from the initiation of NACT was 29.7 months (95% CI, 22.5⁻36.8 months) and 13.4 months (95% CI, 12.5⁻14.4 months), respectively. In the exploratory analysis, conversion surgery after NACT was associated with a better median OS and DFS than upfront surgery (vs. 17.1 months; 95% CI, 15.5⁻18.7 months; p = 0.001 and vs. 7.1 months; 95% CI, 6.4⁻7.8 months; p = 0.005, respectively). There was no difference in length of hospital stay between the two groups, and conversion surgery after NACT showed a significantly lower incidence of postoperative complications than upfront surgery (38% vs. 27%, p = 0.03). Conversion surgery after NACT is a feasible and effective therapeutic strategy for the treatment of patients with BRPC and LAPC. Further clinical trials investigating optimal therapeutic strategies for BRPC and LAPC are warranted.

Acute mental change and hemiplegia after autologous fat injection.

Autologous fat injection is a common procedure used for skin augmentation. It is known to be safe and simple, but severe complications have been reported at times. The authors observed a patient with acute large cerebral infarction including the territories of the anterior and middle cerebral arteries and optic nerve infarction developing after autologous fat transplantation. A 32-year-old woman was referred to the emergency room of our hospital due to sudden stupor. Thirty minutes earlier, she was undergoing cosmetic autologous fat injection into the glabella area by a plastic surgeon at a private clinic. The cause was confirmed to be anterior and middle cerebral arteries infarction on brain imaging studies. When a patient presents abrupt mental change, hemiplegia, ocular pain, or blindness after autologous fat particle injection, physicians must consider cerebral infarction and combined retinal artery occlusion.

Efficacy of diffusion-weighted magnetic resonance imaging performed before therapeutic hypothermia in predicting clinical outcome in comatose cardiopulmonary arrest survivors.

AIM OF THE STUDY: To develop a clinically relevant and qualitative brain magnetic resonance imaging (MRI) scoring system for acute stage comatose cardiac arrest patients. METHODS: Consecutive comatose post-cardiopulmonary arrest patients were prospectively enrolled. Routine brain MRI sequences were scored by two independent and blinded experts. Predefined brain regions were qualitatively scored on diffusion-weighted imaging (DWI) sequences according to the severity of the abnormality on a scale from 0 to 4. The mean score provided by the raters determined poor outcome defined under the Cerebral Performance Categories 3, 4, or 5. DWI scans were repeated after therapeutic hypothermia (TH). The same qualitative scoring system was applied and results were compared to the initial scores. RESULTS: Out of 24 recruited patients, 19 with brain MRI scans were included. Of the 19 included patients, seven showed a good outcome at hospital discharge and 12 patients showed poor neurologic outcome. Median time from the arrest to the initial DWI was 166min (IQR 114-240min). At 100% specificity, the overall, cortex, and cortex plus deep grey nuclei scores predicted poor patient outcome with a sensitivity of 91.7-100% (95% CI). Follow-up DWI scans after TH showed worse results than initial scans. CONCLUSION: A qualitative MRI scoring system effectively assessed the severity of hypoxic-ischaemic brain injury following cardiopulmonary arrest. The scoring system may provide useful prognostic information in comatose cardiopulmonary arrest patients.

Hemichorea after multiple bee stings.

Bee sting is one of the most commonly encountered insect bites in the world. Despite the common occurrence of local and systemic allergic reactions, there are few reports of ischemic stroke after bee stings. To the best our knowledge, there have been no reports on involuntary hyperkinetic movement disorders after multiple bee stings. We report the case of a 50-year-old man who developed involuntary movements of the left leg 24 hours after multiple bee stings, and the cause was confirmed to be a right temporal infarction on a diffusion magnetic resonance imaging scan. Thus, we concluded that the involuntary movement disorder was caused by right temporal infarction that occurred after multiple bee stings.