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Abstract There is no treatment for acute aortic dissection (AAD) targeting inflammatory cells. We aimed to identify the new therapeutic targets associated with inflammatory cells. We characterized the specific distribution of myeloid cells of both human type A AAD samples and a murine AAD model generated using angiotensin II (ANGII) and β-aminopropionitrile (BAPN) by single-cell RNA sequencing (scRNA-seq). We also examined the effect of an anti-interleukin-1β (IL-1β) antibody in the murine AAD model. IL1B+ inflammatory macrophages and classical monocytes were increased in human AAD samples. Trajectory analysis demonstrated that IL1B+ inflammatory macrophages differentiated from S100A8/9/12+ classical monocytes uniquely observed in the aorta of AAD. We found increased infiltration of neutrophils and monocytes with the expression of inflammatory cytokines in the aorta and accumulation of inflammatory macrophages before the onset of macroscopic AAD in the murine AAD model. In blocking experiments using an anti-IL-1β antibody, it improved survival of murine AAD model by preventing elastin degradation. We observed the accumulation of inflammatory macrophages expressing IL-1β in both human AAD samples and in a murine AAD model. Anti-IL-1β antibody could improve the mortality rate in mice, suggesting that it may be a treatment option for AAD.

Abstract Numerous COVID-19 diagnostic imaging Artificial Intelligence (AI) studies exist. However, none of their models were of potential clinical use, primarily owing to methodological defects and the lack of implementation considerations for inference. In this study, all development processes of the deep-learning models are performed based on strict criteria of the “KAIZEN checklist”, which is proposed based on previous AI development guidelines to overcome the deficiencies mentioned above. We develop and evaluate two binary-classification deep-learning models to triage COVID-19: a slice model examining a Computed Tomography (CT) slice to find COVID-19 lesions; a series model examining a series of CT images to find an infected patient. We collected 2,400,200 CT slices from twelve emergency centers in Japan. Area Under Curve (AUC) and accuracy were calculated for classification performance. The inference time of the system that includes these two models were measured. For validation data, the slice and series models recognized COVID-19 with AUCs and accuracies of 0.989 and 0.982, 95.9% and 93.0% respectively. For test data, the models’ AUCs and accuracies were 0.958 and 0.953, 90.0% and 91.4% respectively. The average inference time per case was 2.83 s. Our deep-learning system realizes accuracy and inference speed high enough for practical use. The systems have already been implemented in four hospitals and eight are under progression. We released an application software and implementation code for free in a highly usable state to allow its use in Japan and globally.

Abstract Use of immune checkpoint inhibitors (ICIs) as cancer immunotherapy advances rapidly in the clinic. Despite their therapeutic benefits, ICIs can cause clinically significant immune-related adverse events (irAEs), including myocarditis. However, the cellular and molecular mechanisms regulating irAE remain unclear. Here, we investigate the function of Angiopoietin-like protein 2 (ANGPTL2), a potential inflammatory mediator, in a mouse model of ICI-related autoimmune myocarditis. ANGPTL2 deficiency attenuates autoimmune inflammation in these mice, an outcome associated with decreased numbers of T cells and macrophages. We also show that cardiac fibroblasts express abundant ANGPTL2. Importantly, cardiac myofibroblast-derived ANGPTL2 enhances expression of chemoattractants via the NF-κB pathway, accelerating T cell recruitment into heart tissues. Our findings suggest an immunostimulatory function for ANGPTL2 in the context of ICI-related autoimmune inflammation and highlight the pathophysiological significance of ANGPTL2-mediated cardiac myofibroblast/immune cell crosstalk in enhancing autoimmune responses. These findings overall provide insight into mechanisms regulating irAEs.

Abstract Body mass index (BMI) distribution and its impact on cardiovascular disease (CVD) vary between Asian and western populations. The study aimed to reveal time-related trends in the prevalence of obesity and underweight and safe ranges of BMI in Japanese patients with CVD. We analyzed 5,020,464 records from the national Japanese Registry of All Cardiac and Vascular Diseases—Diagnosis Procedure Combination dataset over time (2012–2019) and evaluated BMI trends and the impact on in-hospital mortality for six acute CVDs: acute heart failure (AHF), acute myocardial infarction (AMI), acute aortic dissection (AAD), ischemic stroke (IS), intracerebral hemorrhage (ICH), and subarachnoid hemorrhage (SAH). Patients were categorized into five groups using the WHO Asian-BMI criteria: underweight (

Compelling evidence suggests a crucial role for Foxp3+ regulatory T cells (Tregs) in the control of atherosclerosis. Although suppression of pro-inflammatory CD4+ T cell immune responses is supposed to be important for athero-protective action of Foxp3+ Tregs, few studies have provided direct evidence for this protective mechanism. We investigated the impact of Foxp3+ Treg depletion on CD4+ T cell immune responses and the development of atherosclerosis under hypercholesterolemia. We employed DEREG (depletion of regulatory T cells) mice on an atherosclerosis-prone low-density lipoprotein receptor-deficient (Ldlr−/−) background, which carry a diphtheria toxin (DT) receptor under the control of the foxp3 gene locus. In these mice, DT injection led to efficient depletion of Foxp3+ Tregs in spleen, lymph nodes and aorta. Depletion of Foxp3+ Tregs augmented CD4+ effector T cell immune responses and aggravated atherosclerosis without affecting plasma lipid profile. Notably, the proportion of pro-inflammatory IFN-γ-producing T cells were increased in spleen and aorta following Foxp3+ Treg depletion, implying that Foxp3+ Tregs efficiently regulate systemic and aortic T cell-mediated inflammatory responses under hypercholesterolemia. Unexpectedly, Foxp3+ Treg depletion resulted in an increase in anti-inflammatory IL-10-producing T cells, which was not sufficient to suppress the augmented proinflammatory T cell immune responses caused by reduced numbers of Foxp3+ Tregs. Our data indicate that Foxp3+ Tregs suppress pro-inflammatory CD4+ T cell immune responses to control atherosclerosis under hypercholesterolemia.

Abstract Background Many studies have compared quality of life of post-intensive care syndrome (PICS) patients with age-matched population-based controls. Many studies on PICS used the 36-item Short Form (SF-36) health survey questionnaire version 2, but lack the data for SF-36 values before and after intensive care unit (ICU) admission. Thus, clinically important changes in the parameters of SF-36 are unknown. Therefore, we determined the frequency of co-occurrence of PICS impairments at 6 months after ICU admission. We also evaluated the changes in SF-36 subscales and interpreted the patients’ subjective significance of impairment. Methods A prospective, multicenter, observational cohort study was conducted in 16 ICUs across 14 hospitals in Japan. Adult ICU patients expected to receive mechanical ventilation for > 48 h were enrolled, and their 6-month outcome was assessed using the questionnaires. PICS definition was based on the physical status, indicated by the change in SF-36 physical component score (PCS) ≥ 10 points; mental status, indicated by the change in SF-36 mental component score (MCS) ≥ 10 points; and cognitive function, indicated by the worsening of Short-Memory Questionnaire (SMQ) score and SMQ score at 6 months

Abstract Background Vertebroplasty with posterior spinal fusion (VP + PSF) is one of the most widely accepted surgical techniques for treating osteoporotic vertebral collapse (OVC). Nevertheless, the effect of the extent of fusion on surgical outcomes remains to be established. This study aimed to evaluate the surgical outcomes of short- versus long-segment VP + PSF for OVC with neurological impairment in thoracolumbar spine. Methods We retrospectively collected data from 133 patients (median age, 77 years; 42 men and 91 women) from 27 university hospitals and their affiliated hospitals. We divided patients into two groups: a short-segment fusion group (S group) with 2- or 3-segment fusion (87 patients) and a long-segment fusion group (L group) with 4- through 6-segment fusion (46 patients). Surgical invasion, clinical outcomes, local kyphosis angle (LKA), and complications were evaluated. Results No significant differences between the two groups were observed in terms of neurological recovery, pain scale scores, and complications. Surgical time was shorter and blood loss was less in the S group, whereas LKA at the final follow-up and correction loss were superior in the L group. Conclusion Although less invasiveness and validity of pain and neurological relief are secured by short-segment VP + PSF, surgeons should be cautious regarding correction loss.

Introduction: Osteoporotic vertebral fracture (OVF) is the most common osteoporotic fracture, and some patients require surgical intervention to improve their impaired activities of daily living with neurological deficits. However, many previous reports have focused on OVF around the thoracolumbar junction, and the surgical outcomes of lumbar OVF have not been thoroughly discussed. We aimed to investigate the surgical outcomes for lumbar OVF with a neurological deficit. Methods: Patients who underwent fusion surgery for thoracolumbar OVF with a neurological deficit were enrolled at 28 institutions. Clinical information, comorbidities, perioperative complications, Japanese Orthopaedic Association scores, visual analog scale scores, and radiographic parameters were compared between patients with lower lumbar fracture (L3-5) and those with thoracolumbar junction fracture (T10-L2). Each patient with lower lumbar fracture (L group) was matched with to patients with thoracolumbar junction fracture (T group). Results: A total 403 patients (89 males and 314 females, mean age: 73.8 ± 7.8 years, mean follow-up: 3.9 ± 1.7 years) were included in this study. Lower lumbar OVF was frequently found in patients with lower bone mineral density. After matching, mechanical failure was more frequent in the L group (L group: 64%, T group: 39%; p < 0.001). There was no difference between groups in the clinical and radiographical outcomes, although the rates of complication and revision surgery were still high in both groups. Conclusions: The surgical intervention for OVF is effective in patients with myelopathy or radiculopathy regardless of the surgical level, although further study is required to improve clinical and radiographical outcomes. Level of evidence: Level III

Abstract Background The optimal treatment of osteoporosis after reconstruction surgery for osteoporotic vertebral fractures (OVF) remains unclear. In this multicentre retrospective study, we investigated the effects of typically used agents for osteoporosis, namely, bisphosphonates (BP) and teriparatide (TP), on surgical results in patients with osteoporotic vertebral fractures. Methods Retrospectively registered data were collected from 27 universities and affiliated hospitals in Japan. We compared the effects of BP vs TP on postoperative mechanical complication rates, implant-related reoperation rates, and clinical outcomes in patients who underwent posterior instrumented fusion for OVF. Data were analysed according to whether the osteoporosis was primary or glucocorticoid-induced. Results A total of 159 patients who underwent posterior instrumented fusion for OVF were included. The overall mechanical complication rate was significantly lower in the TP group than in the BP group (BP vs TP: 73.1% vs 58.2%, p = 0.045). The screw backout rate was significantly lower and the rates of new vertebral fractures and pseudoarthrosis tended to be lower in the TP group than in the BP group. However, there were no significant differences in lumbar functional scores and visual analogue scale pain scores or in implant-related reoperation rates between the two groups. The incidence of pseudoarthrosis was significantly higher in patients with glucocorticoid-induced osteoporosis (GIOP) than in those with primary osteoporosis; however, the pseudoarthrosis rate was reduced by using TP. The use of TP also tended to reduce the overall mechanical complication rate in both primary osteoporosis and GIOP. Conclusions The overall mechanical complication rate was lower in patients who received TP than in those who received a BP postoperatively, regardless of type of osteoporosis. The incidence of pseudoarthrosis was significantly higher in patients with GIOP, but the use of TP reduced the rate of pseudoarthrosis in GIOP patients. The use of TP was effective to reduce postoperative complications for OVF patients treated with posterior fusion.

Summary: The gut microbiome has emerged as a key regulator of obesity; however, its role in brown adipose tissue (BAT) metabolism and association with obesity remain to be elucidated. We found that the levels of circulating branched-chain amino acids (BCAA) and their cognate α-ketoacids (BCKA) were significantly correlated with the body weight in humans and mice and that BCAA catabolic defects in BAT were associated with obesity in diet-induced obesity (DIO) mice. Pharmacological systemic enhancement of BCAA catabolic activity reduced plasma BCAA and BCKA levels and protected against obesity; these effects were reduced in BATectomized mice. DIO mice gavaged with Bacteroides dorei and Bacteroides vulgatus exhibited improved BAT BCAA catabolism and attenuated body weight gain, which were not observed in BATectomized DIO mice. Our data have highlighted a possible link between the gut microbiota and BAT BCAA catabolism and suggest that Bacteroides probiotics could be used for treating obesity.

Aims: Circulating amino acid (AA) abnormalities serve as predictors of adverse outcomes in patients with heart failure (HF). However, the role of the gut microbiota in AA disturbances remains unknown. Thus, we investigated gut microbial functions and their associations with AA metabolic alterations in patients with HF.Methods and Results: We performed whole-genome shotgun sequencing of fecal samples and mass spectrometry-based profiling of AAs in patients with compensated HF. Plasma levels of total essential AAs (EAAs) and histidine were significantly lower in patients with HF than in control subjects. HF patients also displayed increased and decreased abundance of gut microbial genes involved in the degradation and biosynthesis, respectively, of EAAs, including branched-chain AAs (BCAAs) and histidine. Importantly, a significant positive correlation was observed between the abundance of microbial genes involved in BCAA biosynthesis and plasma BCAA levels in patients with HF, but not in controls. Moreover, network analysis revealed that the depletion of Eubacterium and Prevotella, which harbor genes for BCAA and histidine biosynthesis, contributed to decreased abundance of microbial genes involved in the biosynthesis of those EAAs in patients with HF.Conclusions: The present study demonstrated the relationship between gut microbiota and AA metabolic disturbances in patients with HF.

Introduction: The prevalence of patients with osteoporosis continues to increase in aging societies, including Japan. The first choice for managing osteoporotic vertebral compression fracture (OVF) is conservative treatment. Failure in conservative treatment for OVF may lead to non-union or vertebral collapse, resulting in neurological deficit and subsequently requiring surgical intervention. This multicenter nationwide study in Japan was conducted to comprehensively understand the outcomes of surgical treatments for OVF non-union. Methods: This multicenter, retrospective study included 403 patients (89 males, 314 females, mean age 73.8 ± 7.8 years, mean follow-up 3.9 ± 1.7 years) with neurological deficit due to vertebral collapse or non-union after OVF at T10-L5 who underwent fusion surgery with a minimum 1-year follow-up. Radiological and clinical outcomes at baseline and at the final follow-up (FU) were evaluated. Results: OVF was present at a thoracolumbar junction such as T12 (124 patients) and L1 (117 patients). A majority of OVF occurred after a minor trauma, such as falling down (55.3%) or lifting objects (8.4%). Short segment fusion, including affected vertebra, was conducted (mean 4.0 ± 2.0 vertebrae) with 256.8 minutes of surgery and 676.1 g of blood loss. A posterior approach was employed in 86.6% of the patients, followed by a combined anterior and posterior (8.7%), and an anterior (4.7%) approach. Perioperative complications and implant failures were observed in 18.1% and 41.2%, respectively. VAS scores of low back pain (74.7 to 30.8 mm) and leg pain (56.8 to 20.7 mm) improved significantly at FU. Preoperatively, 52.6% of the patients were unable to walk and the rate of non-ambulatory patients decreased to 7.5% at FU. Conclusions: This study demonstrated that substantial improvement in activity of daily living (ADL) was achieved by fusion surgery. Although there was a considerable rate of complications, fusion surgery is beneficial for elderly OVF patients with non-union.

Introduction: Approximately 3% of osteoporotic vertebral fractures develop osteoporotic vertebral collapse (OVC) with neurological deficits, and such patients are recommended to be treated surgically. However, a proximal junctional fracture (PJFr) following surgery for OVC can be a serious concern. Therefore, the aim of this study is to identify the incidence and risk factors of PJFr following fusion surgery for OVC. Methods: This study retrospectively analyzed registry data collected from facilities belonging to the Japan Association of Spine Surgeons with Ambition (JASA) in 2016. We retrospectively analyzed 403 patients who suffered neurological deficits due to OVC below T10 and underwent corrective surgery; only those followed up for 2 years were included. Potential risk factors related to the PJFr and their cut-off values were calculated using multivariate logistic regression analysis and receiver operating characteristic (ROC) analysis. Results: Sixty-three patients (15.6%) suffered PJFr during the follow-up (mean 45.7 months). In multivariate analysis, the grade of osteoporosis (grade 2, 3: adjusted odds ratio (aOR) 2.92; p=0.001) and lower instrumented vertebra (LIV) level (sacrum: aOR 6.75; p=0.003) were independent factors. ROC analysis demonstrated that lumbar bone mineral density (BMD) was a predictive factor (area under curve: 0.72, p=0.035) with optimal cut-off value of 0.61 g/cm2 (sensitivity, 76.5%; specificity, 58.3%), but that of the hip was not (p=0.228). Conclusions: PJFr was found in 16% cases within 4 years after surgery; independent risk factors were severe osteoporosis and extended fusion to the sacrum. The lumbar BMD with cut-off value 0.61 g/cm2 may potentially predict PJFr. Our findings can help surgeons select perioperative adjuvant therapy, as well as a surgical strategy to prevent PJFr following surgery.

Abstract Background To date, there have been little published data on surgical outcomes for patients with PD with thoracolumbar OVF. We conducted a retrospective multicenter study of registry data to investigate the outcomes of fusion surgery for patients with Parkinson’s disease (PD) with osteoporotic vertebral fracture (OVF) in the thoracolumbar junction. Methods Retrospectively registered data were collected from 27 universities and their affiliated hospitals in Japan. In total, 26 patients with PD (mean age, 76 years; 3 men and 23 women) with thoracolumbar OVF who underwent spinal fusion with a minimum of 2 years of follow-up were included (PD group). Surgical invasion, perioperative complications, radiographic sagittal alignment, mechanical failure (MF) related to instrumentation, and clinical outcomes were evaluated. A control group of 296 non-PD patients (non-PD group) matched for age, sex, distribution of surgical procedures, number of fused segments, and follow-up period were used for comparison. Results The PD group showed higher rates of perioperative complications (p

Data presented in this article are supplementary material to our research article entitled “Impact of CD14++CD16+ monocytes on coronary plaque vulnerability assessed by optical coherence tomography in coronary artery disease patients” [1]. This article contains the data of study population, diagnostic ability of CD14++CD16+ monocytes to identify thin-cap fibroatheromas, and association between laboratory variables and plaque properties.

Gut microbiota imbalance plays an important role in the pathogenesis of various diseases. Here, we determined microbe-microbe interactions and gut microbiome stability in a Japanese population with varying body mass indices (BMIs) and enterotypes. Using 16S ribosomal RNA gene sequencing, we analyzed gut microbial data from fecal samples obtained from 3,365 older Japanese individuals. The individuals were divided into lean, normal, and obese groups based on their BMIs. They were further categorized according to their gut microbiota enterotypes: Bacteroides (enterotype B), Prevotella (enterotype P), and Ruminococcus (enterotype R). We obtained data on different host factors, such as age, BMI, and disease status, using a survey questionnaire evaluated by the Mykinso gut microbiome testing service. Subsequently, we evaluated the co-occurrence network. Individual differences in BMI were associated with differences in co-occurrence networks. By exploring the network topology based on BMI status, we observed that the network density was lower in the lean group than that in the normal group. Furthermore, a simulation-based stability analysis revealed a lower resistance index in the lean group than those in the other two groups. Our results provide insights into various microbe-microbe interactions and gut microbial stability and could aid in developing appropriate therapeutic strategies targeting gut microbiota modulation to manage frailty. [ABSTRACT FROM AUTHOR]

Abstract Background Previously, we have reported that daily glucose fluctuations could affect coronary plaque vulnerability, but the underlying mechanisms remained unclear. This study sought to investigate the impact of CD14++CD16+ monocytes on plaque vulnerability, as assessed by virtual histology intravascular ultrasound (VH-IVUS), as well as their relationship to fluctuating glucose levels in patients with asymptomatic coronary artery disease (CAD). Methods Fifty-one patients with asymptomatic CAD, who were undergoing lipid-lowering therapy and underwent VH-IVUS evaluation for angiographically mild to moderate lesions, were enrolled in the study. Standard VH-IVUS parameters, including the percentage volume of the necrotic core (%NC) within the plaque and the presence of a virtual histology thin-cap fibroatheroma (VH-TCFA), were then evaluated. Additionally, monocyte subsets were assessed by flow cytometry, and daily glucose fluctuations were analyzed by measuring the mean amplitude of glycemic excursion (MAGE). Results Among 82 plaques from 22 diabetes mellitus (DM) patients and 29 non-DM patients, 15 VH-TCFAs were identified. CD14++CD16+ monocyte counts significantly correlated with both %NC and the presence of VH-TCFA (%NC: r = 0.339, p = 0.002; VH-TCFA: p = 0.003). Multivariate logistic regression analysis revealed that CD14++CD16+ monocyte counts were independently associated with VH-TCFA (odds ratio = 1.029, p = 0.004). Furthermore, CD14++CD16+ monocyte counts were significantly correlated with the MAGE score in the non-DM patients (r = 0.544, p = 0.005). Conclusions CD14++CD16+ monocyte levels are associated with coronary plaque vulnerability and can serve as a biomarker for VH-TCFA in patients with CAD undergoing lipid-lowering therapy. In patients without DM, glucose fluctuations may alter the balance of monocyte subsets. Trial registration UMIN Registry number: UMIN000021228

The gut microbiota were shown to play critical roles in the development of atherosclerosis, but the detailed mechanism is limited. The purpose of this study is to clarify the influence of gut microbiota on atherogenesis via lipid metabolism and systemic inflammation. Germ-free or conventionally raised (Conv) ApoE-deficient (ApoE−/−) mice were fed chow diet and euthanized at 20 weeks of age. We found that the lack of gut microbiota in ApoE−/− mice caused a significant increase in the plasma and hepatic cholesterol levels compared with Conv ApoE−/− mice. The absence of gut microbiota changed the bile acid composition in the ileum, which was associated with activation of the enterohepatic fibroblast growth factor 15, fibroblast growth factor receptor 4 axis, and reduction of cholesterol 7α-hydroxylase and hepatic bile acid synthesis, resulting in the accumulation of liver cholesterol content. However, we found that the lack of microbiota caused a significant reduction in atherosclerotic lesion formation compared with Conv ApoE−/− mice, which might be associated with the attenuation of lipopolysaccharide-mediated inflammatory responses. Our findings indicated that the gut microbiota affected both hypercholesterolemia and atherogenesis in mice.

Introduction: Posterior lumbar interbody fusion (PLIF) has produced satisfactory clinical outcomes; however, all previous reports have only included evaluations by surgeon-based methods. The purpose of this study was to investigate patient-based surgical outcomes and the factors associated with patient satisfaction for PLIF. Methods: Patients who underwent PLIF for lumbar spondylolisthesis were reviewed (n=443). The average follow-up period was 8 years. Surgical outcomes were assessed using an original questionnaire, a numerical rating scale (NRS), the 36-Item Short Form Health Survey (SF-36), the Japanese Orthopedic Association (JOA) score, and the recovery rate. The original questionnaire consisted of five categories, with patient-evaluated score out of 100 points for surgery, satisfaction, improvement, recommendation to others, and willingness to undergo repeat surgery on a 5-point scale. According to the questionnaire responses, patient-based outcomes were divided into three groups: positive, intermediate, and negative and were compared with the NRS, SF-36, and JOA scores. Furthermore, factors associated with patient satisfaction were examined. Results: A total of 273 patients responded. Response rate was 62%. The average patient-evaluated score for surgery was 82 points. In terms of satisfaction section, positive, intermediate, and negative response rates were 82%, 7%, and 11%, respectively. With respect to other sections, positive, intermediate, and negative response rates were 87%, 7%, and 6% in improvement section; 66%, 23%, and 11% in recommending section; and 72%, 18%, and 10% in repeat section, respectively. The average pre- and postoperative JOA scores were 12 and 24, respectively. Significant correlations were detected between patient-based surgical outcomes and the NRS scores, physical component scores of the SF-36, and the JOA score. Postoperative permanent motor loss and multiple revision surgery were the major factors related to a negative response. Conclusions: High satisfaction rate to PLIF and significant correlation between patient- and surgeon-based surgical outcomes were detected. Postoperative permanent motor loss and multiple revision surgery were the major factors related to a negative response.

Cardiovascular diseases (CVDs) have become a major health problem because of the associated high morbidity and mortality rates observed in affected patients. Gut microbiota has recently been implicated as a novel endocrine organ that plays critical roles in the regulation of cardiometabolic and renal functions of the host via the production of bioactive metabolites. This review investigated the evidence from several clinical and experimental studies that indicated an association between the gut microbiota-derived toxins and CVDs. We mainly focused on the pro-inflammatory gut microbiota-derived toxins, namely lipopolysaccharides, derived from Gram-negative bacteria, and trimethylamine N-oxide and described the present status of research in association with these toxins, including our previous research findings. Several clinical studies aimed at exploring the effectiveness of reducing the levels of these toxins to inhibit cardiovascular events are currently under investigation or in the planning stages. We believe that some of the methods discussed in this review to eliminate or reduce the levels of such toxins in the body could be clinically applied to prevent CVDs in the near future.

Study DesignClinical case series.PurposeIn the posterior lumbar interbody fusion (PLIF) procedure in our institute, the cephalad screw trajectory follows a mediolateral and caudocephalad directed path according to the original cortical bone trajectory (CBT) method. However, the starting point of the caudal screw is at the medial border of the pedicle on an articular surface of the superior articular process, and the trajectory takes a mediolateral path parallel to the cephalad endplate. The incidence of caudal screw loosening after PLIF with this modified CBT screw method was investigated, and significant risk factors for caudal screw loosening were evaluated.Overview of LiteratureA biomechanical study of this modified caudal screw trajectory using the finite element method reported about a 20% increase in uniaxial yield pullout load compared with the traditional trajectory. However, there has been no clinical study concerning the fixation strength of this modified caudal screw trajectory.MethodsThe subjects were 193 consecutive patients who underwent single-level PLIF with modified CBT screw fixation. Caudal screw loosening was checked in computed tomography at 6 months after surgery, and screw loosening was defined as a radiolucency of 1 mm or more at the bone-screw interface.ResultsThe incidence of caudal screw loosening after lumbosacral PLIF (46.2%) was significantly higher than that after floating PLIF (6.0%). No significant differences in sex, brand of the instruments, and diameter and length of the caudal screw were evident between patients with and without caudal screw loosening. Patients with caudal screw loosening were significantly older at the time of surgery than patients without caudal screw loosening.ConclusionsFixation strength of the caudal screw after floating PLIF with this modified CBT screw technique was sufficiently acceptable. Fixation strength after the lumbosacral procedure was not.

BackgroundPathogenic immune responses are known to play an important role in abdominal aortic aneurysm (AAA) development. Ultraviolet B (UVB) irradiation has been demonstrated to have therapeutic potential not only for cutaneous diseases but also for systemic inflammatory diseases in mice by suppressing immunoinflammatory responses. We investigated the effect of UVB irradiation on experimental AAA. Methods and ResultsWe used an angiotensin II–induced AAA model in apolipoprotein E–deficient mice fed a high‐cholesterol diet. Mice aged 10 weeks were irradiated with 5 kJ/m2 UVB once weekly for 6 weeks (UVB‐irradiated, n=38; nonirradiated, n=42) and were euthanized for evaluation of AAA formation at 16 weeks. Overall, 93% of angiotensin II–infused mice developed AAA, with 60% mortality possibly because of aneurysm rupture. UVB irradiation significantly decreased the incidence (66%) and mortality (29%) of AAA (P=0.004 and P=0.006, respectively). UVB‐irradiated mice had significantly smaller diameter AAA (P=0.008) and fewer inflammatory cells in the aortic aneurysm tissue than nonirradiated mice, along with systemic expansion of CD4+Foxp3+ regulatory T cells and decreased effector CD4+CD44highCD62Llow T cells in para‐aortic lymph nodes. Genetic depletion of regulatory T cells abrogated these beneficial effects of UVB treatment, demonstrating a critical role of regulatory T cells. ConclusionsOur data suggest that UVB‐dependent expansion of regulatory T cells has beneficial effects on experimental AAA and may provide a novel strategy for the treatment of AAA.