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Introduction: This study aimed to compare the outcomes of corrective fusion for adult spinal deformity (ASD) in older people using two different sagittal correction goals: the conventional formula of “pelvic incidence (PI)-lumbar lordosis (LL) mismatch 20° or LL

Introduction: Postoperative spinal epidural hematoma (PSEH) is a severe complication of spinal surgery that necessitates accurate and timely diagnosis. This study aimed to assess the accuracy of ultrasonography as an alternative diagnostic tool for PSEH after microendoscopic laminotomy (MEL) for lumbar spinal stenosis, comparing it with magnetic resonance imaging (MRI). Methods: A total of 65 patients who underwent MEL were evaluated using both ultrasound- and MRI-based classifications for PSEH. Intra- and interrater reliabilities were analyzed. Furthermore, ethical standards were strictly followed, with spine surgeons certified by the Japanese Orthopaedic Association performing evaluations. Results: Among the 65 patients, 91 vertebral segments were assessed. The intra- and interrater agreements for PSEH classification were almost perfect for both ultrasound (κ=0.824 [95% confidence interval (CI) 0.729-0.918] and κ=0.810 [95% CI 0.712-0.909], respectively) and MRI (κ=0.839 [95% CI 0.748-0.931] and κ=0.853 [95% CI 0.764-0.942], respectively). The results showed high concordance between ultrasound- and MRI-based classifications, validating the reliability of ultrasound in postoperative PSEH evaluation. Conclusions: This study presents a significant advancement by introducing ultrasound as a precise and practical alternative to MRI for PSEH evaluation. The comparable accuracy of ultrasound to MRI, rapid bedside assessments, and radiation-free nature make it valuable for routine postoperative evaluations. Despite the limitations related to specific surgical contexts and clinical outcome assessment, the clinical potential of ultrasound is evident. It offers clinicians a faster, cost-effective, and repeatable diagnostic option, potentially enhancing patient care. This study establishes the utility of ultrasound in evaluating postoperative spinal epidural hematomas after MEL. With high concordance to MRI, ultrasound emerges as a reliable, practical, and innovative tool, promising improved diagnostic efficiency and patient outcomes. Further studies should explore its clinical impact across diverse surgical scenarios.

Introduction: Despite the absence of bone grafting in the area outside the cage, lateral bridging callus outside cages (LBC) formation is often observed here following extreme lateral interbody fusion (XLIF) conversely to conventional methods of transforaminal lumbar interbody fusion and posterior lumbar interbody fusion. The LBC, which may increase stabilization and decrease nonunion rate in treated segments, has rarely been described. This study aimed to identify the incidence and associated factors of LBC following XLIF. Methods: We enrolled 136 consecutive patients [56 males, 80 females; mean age 69.6 (42-85) years] who underwent lumbar fusion surgery using XLIF, including L4/5 level with posterior fixation at a single institution between February 2013 and February 2018. One year postoperatively, the treated L4/5 segments were divided into the LBC formation and non-formation groups. Potential influential factors, such as age, sex, body mass index, bone density, height of cages, cage material (titanium or polyetheretherketone [PEEK]), presence or absence of diffuse idiopathic skeletal hyperostosis (DISH), and radiological parameters, were evaluated. Multivariate logistic regression analysis was performed for factors significantly different from the univariate analysis. Results: The incidence of LBC formation was 58.8%. Multivariate logistic regression analysis showed that the length of osteophytes [+1 mm; odds ratio, 1.29; 95% confidence interval, 1.17-1.45; p

Abstract Some older adults with spinal deformity maintain standing posture via pelvic compensation when their center of gravity moves forward. Therefore, evaluations of global alignment should include both pelvic tilt (PT) and seventh cervical vertebra-sagittal vertical axis (C7-SVA). Here, we evaluate standing postures of older adults using C7-SVA with PT and investigate factors related to postural abnormality. This cross-sectional study used an established population-based cohort in Japan wherein 1121 participants underwent sagittal whole-spine radiography in a standing position and bioelectrical impedance analysis for muscle mass measurements. Presence of low back pain (LBP), visual analog scale (VAS) of LBP, and LBP-related disability (Oswestry Disability Index [ODI]) were evaluated. Based on the PT and C7-SVA, the participants were divided into four groups: normal, compensated, non-compensated, and decompensated. We defined the latter three categories as “malalignment” and examined group characteristics and factors. There were significant differences in ODI%, VAS and prevalence of LBP, and sarcopenia among the four groups, although these were non-significant between non-compensated and decompensated groups on stratified analysis. Moreover, the decompensated group was significantly associated with sarcopenia. Individuals with pelvic compensation are at increased risk for LBP and related disorders even with the C7-SVA maintained within normal range.

Abstract Background This study aimed to determine the feasibility of ultrasonography in the assessment of cervical vertebral artery (VA) injury as an alternative to computed tomography angiography (CTA) in the emergency room. Methods We analyzed 50 VAs from 25 consecutive patients with cervical spine injury that had been admitted to our emergency room. Ultrasonography and CTA were performed to assess the VA in patients with cervical spine injury. We examined the sensitivity and specificity of ultrasonography compared with CTA. Results Among these VAs, six were occluded on CTA. The agreement between ultrasonography and CTA was 98% (49/50) with 0.92 Cohen's Kappa index. The sensitivity, specificity, and positive and negative predictive values of ultrasonography were 100%, 97.7%, 85.7%, and 100%, respectively. In one case with hypoplastic VA, the detection of flow in the VA by ultrasonography differed from detection by CTA. Meanwhile, there were two cases in which VAs entered at C5 transverse foramen rather than at C6 level. However, ultrasonography could detect the blood flow in these VAs. Conclusions Ultrasonography had a sensitivity of 100% compared with CTA in assessment of the VA. Ultrasonography can be used as an initial screening test for VA injury in the emergency room.

Introduction: Although intraoperative spinal neuromonitoring (IONM) is recommended for spine surgeries, there are no guidelines regarding its use in Japan, and its usage is mainly based on the surgeon's preferences. Therefore, this study aimed to provide an overview of the current trends in IONM usage in Japan. Methods: In this web-based survey, expert spine surgeons belonging to the Japanese Society for Spine Surgery and Related Research were asked to respond to a questionnaire regarding IONM management. The questionnaire covered various aspects of IONM usage, including the preferred modality, operation of IONM, details regarding muscle-evoked potential after electrical stimulation of the brain (Br(E)-MsEP), and need for consistent use of IONM in major spine surgeries. Results: Responses were received from 134 of 186 expert spine surgeons (response rate, 72%). Of these, 124 respondents used IONM routinely. Medical staff rarely performed IONM without a medical doctor. Br(E)-MsEP was predominantly used for IONM. One-third of the respondents reported complications, such as bite injuries caused by Br(E)-MsEP. Interestingly, two-thirds of the respondents did not plan responses to alarm points. Intramedullary spinal cord tumor, scoliosis (idiopathic, congenital, or neuromuscular in pediatric), and thoracic ossification of the posterior longitudinal ligament were representative diseases that require IONM. Conclusions: IONM has become an essential tool in Japan, and Br(E)-MsEP is a predominant modality for IONM at present. Although we investigated spine surgeries for which consistent use of IONM is supported, a cost-benefit analysis may be required.

Human Rad51 protein (HsRad51)-promoted DNA strand exchange, a crucial step in homologous recombination, is regulated by proteins and calcium ions. Both the activator protein Swi5/Sfr1 and Ca2+ ions stimulate different reaction steps and induce perpendicular DNA base alignment in the presynaptic complex. To investigate the role of base orientation in the strand exchange reaction, we examined the Ca2+ concentration dependence of strand exchange activities and structural changes in the presynaptic complex. Our results show that optimal D-loop formation (strand exchange with closed circular DNA) required Ca2+ concentrations greater than 5 mM, whereas 1 mM Ca2+ was sufficient for strand exchange between two oligonucleotides. Structural changes indicated by increased fluorescence intensity of poly(dεA) (a poly(dA) analog) reached a plateau at 1 mM Ca2+. Ca2+ > 2 mM was required for saturation of linear dichroism signal intensity at 260 nm, associated with rigid perpendicular DNA base orientation, suggesting a correlation with the stimulation of D-loop formation. Therefore, Ca2+ exerts two different effects. Thermal stability measurements suggest that HsRad51 binds two Ca2+ ions with KD values of 0.2 and 2.5 mM, implying that one step is stimulated by one Ca2+ bond and the other by two Ca2+ bonds. Our results indicate parallels between the Mg2+ activation of RecA and the Ca2+ activation of HsRad51.

Introduction: Long fusion surgery for adult spinal deformity may restrict activities of daily living due to lumbar stiffness. While the Lumbar Stiffness Disability Index (LSDI) can help assess lumbar stiffness, in Asia the external validity of this questionnaire has not been sufficiently examined. We performed the psychometric evaluation and external validation of the Japanese version of the LSDI (LSDI-J). Methods: Fifty consecutive patients (14 males and 36 females; mean age 70.6 years) who underwent lumbar fusion surgery at our institution a minimum of one year after surgery and who visited the outpatient clinic between April and May 2019, were surveyed using the LSDI-J. The mean number of fusion levels was 4.4. Cronbach's alpha coefficients were calculated for internal consistency, and the intraclass correlation coefficient (ICC) was calculated to evaluate reliability. External validity was assessed by comparisons with the Oswestry Disability Index (ODI), the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ), and the lumbar range of motion (LROM) with LSDI-J scores. Results: Cronbach's alpha coefficient was 0.652 overall, and 0.849 after excluding Question 10 due to a low response rate. The ICC was 0.824 overall and 0.851 after excluding Question 10. The correlation with the ODI was 0.684, and the correlation coefficients with each domain of the JOABPEQ ranged from −0.590 to −0.413, indicating moderate correlation. However, LROM and the LSDI-J were not correlated (r=−0.055, P=0.734). Conclusions: The LSDI-J may not be suitable in Japan because there was no correlation with LROM, the most important factor for external validity. It may be necessary to investigate why the LSDI-J did not apply to the Japanese population in terms of lower limb function. Alternatively, a unique method may be needed to assess lumbar stiffness disability that is more suitable for actual clinical practice in Japan.

Introduction: Adult spinal fusion surgery improves lumbar alignment and patient satisfaction. Adult spinal deformity surgery improves saggital balance not only lumbar lesion, but also at hip joint coverage. It was expected that hip joint coverage rate was improved and joint stress decreased. However, it was reported that adjacent joint disease at hip joint was induced by adult spinal fusion surgery including sacroiliac joint fixation on an X-ray study. The mechanism is still unclear. We aimed to investigate the association between lumbosacral fusion including sacroiliac joint fixation and contact stress of the hip joint. Methods: A 40-year-old woman with intact lumbar vertebrae underwent computed tomography. A three-dimensional nonlinear finite element model was constructed from the L4 vertebra to the femoral bone with triangular shell elements (thickness, 2 mm; size, 3 mm) for the cortical bone's outer surface and 2-mm (lumbar spine) or 3-mm (femoral bone) tetrahedral solid elements for the remaining bone. We constructed the following four models: a non-fusion model (NF), a L4-5 fusion model (L5F), a L4-S1 fusion model (S1F), and a L4-S2 alar iliac screw fixation model (S2F). A compressive load of 400 N was applied vertically to the L4 vertebra and a 10-Nm bending moment was additionally applied to the L4 vertebra to stimulate flexion, extension, left lateral bending, and axial rotation. Each model's hip joint's von Mises stress and angular motion were analyzed. Results: The hip joint's angular motion in NF, L5F, S1F, and S2F gradually increased; the S2F model presented the greatest angular motion. Conclusions: The average and maximum contact stress of the hip joint was the highest in the S2F model. Thus, lumbosacral fusion surgery with sacroiliac joint fixation placed added stress on the hip joint. We propose that this was a consequence of adjacent joint spinopelvic fixation. Lumbar-to-pelvic fixation increases the angular motion and stress at the hip joint.

Introduction: Sacroiliac joint pain (SIJP) is one of the pathological conditions of adjacent segment disorders occurring after adult spinal deformity (ASD) surgery. This study aimed to test the hypothesis that even in ASD surgery using S2 alar-iliac (S2AI) screws, SIJP can develop much earlier than reported previously and can be rescued by ultrasound-guided sacroiliac joint block. Methods: Overall, 94 patients with ASD treated with long spinal fusion using S2AI screws were prospectively investigated for SIJP postoperatively, and the effect of ultrasound-guided sacroiliac joint block was evaluated. Additionally, the relationship between the symptomatic side of the SIJP and the surgical procedure; the preoperative and postoperative whole-spine sagittal and coronal alignment, lumbar pelvis sagittal plane alignment, and pelvic incidence-lumbar lordosis were retrospectively compared between the groups with and without SIJP. Results: Eleven of 94 cases (11.7%) developed SIJP. The average onset was 12.0 (±6.2) days after surgery. The “one-finger test,”“Gaenslen test,” and “tenderness of the posterosuperior iliac spine” had high positivity rates for SIJP. Night pain occurred in 81.8% of patients and was one of the diagnostic features. There were no significant relationships between the symptomatic side of SIJP and the approach-side of lumbar interbody fusion, donor site of the iliac bone graft, or malposition of the S2AI screw. There were no significant differences in preoperative characteristics and radiological parameters between the SIJP-positive and -negative groups preoperatively, postoperatively, or in postoperative changes. Two of the 11 cases required the SIJ block four times, but all patients eventually achieved >70% pain relief with no recurrence. Conclusions: For good pain control and physical therapy, the fact that early buttock-groin pain after spinal fusion surgery has a 12% likelihood of being due to SIJP and can be relieved with the ultrasound-guided SIJ block is clinically important for diagnosis and pain management.

Introduction: Long-term clinical outcomes of microendoscopic laminotomy (MEL) for patients with multilevel radiographic lumbar spinal canal stenosis (LSS) have not been widely explored. The clinical significance and natural progression of additional untreated levels (e.g., remaining radiographic (RR)-LSS not addressed by selective MEL) remain unknown. This retrospective study aimed to investigate the long-term clinical outcomes of selective MEL in LSS patients and compare outcomes between patients with and without remaining RR-LSS to determine the efficacy of this procedure. Methods: Forty-nine patients at a single center underwent posterior spinal microendoscopic decompression surgery for neurogenic claudication or radicular leg pain in moderate-to-severe spinal stenosis. The patients were categorized into the RR-LSS-positive and RR-LSS-negative cohorts based on unaddressed levels of stenosis. Pre-operative and 10-year follow-up evaluations, including the Japanese Orthopedic Association (JOA) score, visual analog scale (VAS) score for low back pain and leg pain, Oswestry Disability Index (ODI), and satisfaction, were compared between the groups. Additionally, the need for reoperation was determined. Results: MEL significantly improved JOA scores, lumbar VAS, and ODI over the 10-year postoperative period. Pre-operative characteristics and postoperative outcomes were not significantly different between the cohorts. Overall, 18.4% (9/49) of patients required reoperation during the follow-up period. The reoperation rate in the RR-LSS-positive (13.8%; 4/29) group was similar to that in the RR-LL-negative (15.0%; 3/20) group. Conclusions: MEL is effective for lumbar stenosis, with improved clinical outcomes up to 10 years following surgery. Selective MEL, addressing only symptomatic levels in multilevel stenosis, with residual remaining lumbar stenosis, is similarly effective without increased reoperation rates. Surgeons may consider more limited selective decompression in patients with multilevel stenosis, avoiding the risk and invasiveness of extensive procedures. Level of Evidence: Level III.

Abstract Acute myeloid leukemia (AML) patients older than 65 years have a poor prognosis. Recently, CAR (C-reactive-protein/albumin ratio) has been actively reported as a prognostic index reflecting the nutritional and inflammatory status of elderly patients with solid tumors, but the usefulness of this index as a prognostic indicator in transplant-ineligible elderly AML patients has not been investigated. We studied genetic alterations and CARs in 188 newly diagnosed AML patients aged 65 years or older who were treated in a multicenter setting and had treated without HSCT. Both NCCN 2017 risk group, reflecting the genetic component of the tumor, and CAR, reflecting the inflammatory and nutritional status of the patient, successfully stratified the overall survival (OS) of the patients (2-year OS; CAR low vs high, 42.3% vs 17.8%, P

Abstract Background Airway complications are the most serious complications after anterior cervical decompression and fusion (ACDF) and can have devastating consequences if their detection and intervention are delayed. Plain radiography is useful for predicting the risk of dyspnea by permitting the comparison of the prevertebral soft tissue (PST) thickness before and after surgery. However, it entails frequent radiation exposure and is inconvenient. Therefore, we aimed to overcome these problems by using ultrasonography to evaluate the PST and upper airway after ACDF and investigate the compatibility between X-ray and ultrasonography for PST evaluation. Methods We included 11 radiculopathy/myelopathy patients who underwent ACDF involving C5/6, C6/7, or both segments. The condition of the PST and upper airway was evaluated over 14 days. The Bland–Altman method was used to evaluate the degree of agreement between the PST values obtained using radiography versus ultrasonography. The Pearson correlation coefficient was used to determine the relationship between the PST measurement methods. Single-level and double-level ACDF were performed in 8 and 3 cases, respectively. Results PST and upper airway thickness peaked on postoperative day 3, with no airway complications. The Bland–Altman bias was within the prespecified clinically nonsignificant range: 0.13 ± 0.36 mm (95% confidence interval 0.04–0.22 mm). Ultrasonography effectively captured post-ACDF changes in the PST and upper airway thickness and detected airway edema. Conclusions Ultrasonography can help in the continuous assessment of the PST and the upper airway as it is simple and has no risk of radiation exposure risk. Therefore, ultrasonography is more clinically useful to evaluate the PST than radiography from the viewpoint of invasiveness and convenience.

Abstract Background Lateral interbody release (LIR) via a transpsoas lateral approach is a surgical strategy to address degenerative lumbar scoliosis (DLS) patients with anterior autofusion of vertebral segments. This study aimed to characterize the clinical and radiographic outcomes of this lumbar reconstruction strategy using LIR to achieve anterior column correction. Methods Data for 21 fused vertebrae in 17 consecutive patients who underwent LIR between January 2014 and March 2020 were reviewed. Demographic and intraoperative data were recorded. Radiographic parameters were assessed preoperatively and at final follow-up, including segmental lordotic angle (SLA), segmental coronal angle (SCA), bone union rate, pelvic incidence (PI), lumbar lordosis (LL), pelvic tilt, sacral slope, PI-LL mismatch, sagittal vertical axis, Cobb angle, and deviation of the C7 plumb line from the central sacral vertical line. Clinical outcomes were evaluated using Oswestry Disability Index (ODI), visual analog scale (VAS) scores for low back and leg pain, and the short form 36 health survey questionnaire (SF-36) postoperatively and at final follow-up. Complications were also assessed. Results Mean patient age was 70.3 ± 4.8 years and all patients were female. Average follow-up period was 28.4 ± 15.3 months. Average procedural time to perform LIR was 21.3 ± 9.7 min and was not significantly different from traditional lateral interbody fusion at other levels. Blood loss per single segment during LIR was 38.7 ± 53.2 mL. Fusion rate was 100.0% in this cohort. SLA improved significantly from − 7.6 ± 9.2 degrees preoperatively to 7.0 ± 8.8 degrees at final observation and SCA improved significantly from 19.1 ± 7.8 degrees preoperatively to 8.7 ± 5.9 degrees at final observation (P

Abstract Background Although there are reports on the effectiveness of microendoscopic laminotomy using a spinal endoscope as decompression surgery for lumbar spinal stenosis, predicting the improvement of low back pain (LBP) still poses a challenge, and no clear index has been established. This study aimed to investigate whether microendoscopic laminotomy for lumbar spinal stenosis improves low back pain and determine the preoperative predictors of residual LBP. Methods In this single-center retrospective study, we examined 202 consecutive patients who underwent microendoscopic laminotomy for lumbar spinal stenosis with a preoperative visual analog scale (VAS) score for LBP of ≥40 mm. The lumbar spine Japanese Orthopaedic Association (JOA), and VAS scores for LBP, leg pain (LP), and leg numbness (LN) were examined before and at 1 year after surgery. Patients with a 1-year postoperative LBP-VAS of ≥25 mm composed the residual LBP group. The preoperative predictive factors associated with postoperative residual LBP were analyzed. Results JOA scores improved from 14.1 preoperatively to 20.2 postoperatively (p

Abstract Studies have suggested a relationship between sagittal spinal malalignment and low back pain (LBP). The current study investigated the relationship of spinal alignment with LBP and physical performance in 1491 individuals who attended the second follow-up visit of the Wakayama Spine Study. The sagittal vertical axis at C7 (C7 SVA) was measured by a spine surgeon. The occurrence of LBP within one month, pain intensity, Oswestry Disability Index (ODI), and physical performance (grip strength, 6-m walking time, chair stand test, one-leg standing test) were also evaluated. LBP in the previous month was determined using ODI, and indicators of physical performance were measured. The mean C7 SVA was 11.0 ± 42.7 mm and was significantly greater in older participants (p

Abstract Kitchen elbow sign (KE-Sign) is a skin abnormality on the extensor side of the elbow and forearm that is often observed in patients with adult spinal deformity (ASD). The significance of KE-Sign in surgical cases was investigated. Overall, 114 patients with ASD treated with long spinal fusion were reviewed and divided into KE-Sign positive and negative groups. The preoperative and 1-year follow-up evaluations included radiographic parameters [C7 sagittal vertical axis (SVA), pelvic incidence (PI) and lumbar lordosis (LL)], the Oswestry Disability Index (ODI), visual analogue scales (VASs) for low back pain, leg pain, and satisfaction, and Short Form 36 questionnaire (SF-36). Multi-regression analysis was performed to identify patient satisfaction predictors and improvement in the ODI as dependent variables and preoperative background factors as independent variables. Preoperative characteristics showed no significant difference between both groups. Improvement in the ODI and VAS for satisfaction were significantly superior in the KE-Sign positive group. In multiple regression analysis, KE-Sign and preoperative ODI were significantly associated with improvement in the ODI; age, KE-Sign, preoperative low back pain VAS, and leg pain VAS were significantly associated with satisfaction. KE-Sign can be a predictor of better surgical outcomes in ASD patients.

An intraoperative functional spinal cord monitoring system is a technology used by spine and spinal cord surgeons to perform a safe surgery and to gain further surgical proficiency. However, no existing clinical neurophysiological method used in the operating room can monitor all complex spinal cord functions. Therefore, by observing the activities of certain neural action potentials transferred via limited neural tissues, surgeons need to deductively estimate the function of the whole spinal cord. Thus, as the number of spinal cord functions that need to be observed increases, spinal cord monitoring can be more reliable. However, in some situations, critical decision-making is affected by the limited capability of these methods. Nevertheless, good teamwork enables sharing of seamless information within the team composed of a surgeon, anesthesiologist, monitoring technician and nurses greatly contributes to making quick and accurate decisions. The surgeon, who is the person in charge of the team, should communicate with multidisciplinary team members using common technical terms. For this reason, spine and spinal cord surgeons must have appropriate knowledge of the methods currently used, especially of their utility and limitations. To date, at least six electrophysiological methods are available for clinical utilization: three are used to monitor sensory-related tracts, and three are used to monitor motor-related spinal cord functions. If surgeons perform electrode setting, utilizing their expertise, then the range of available methods is broadened, and more meticulous intraoperative functional spinal cord monitoring can be carried out. Furthermore, if the team members share information effectively by utilizing a clinically feasible judicious checklist or tools, then spinal cord monitoring will be more reliable.

Objectives This prospective study aimed to determine the association between radiographic lumbar spinal stenosis (LSS) and the quality of life (QOL) in the general Japanese population. Methods The severity of radiographic LSS was qualitatively graded on axial magnetic resonance images as follows: no stenosis, mild stenosis with ≤1/3 narrowing, moderate stenosis with a narrowing between 1/3 and 2/3, and severe stenosis with > 2/3 narrowing. Patients less than 40 years of age and those who had undergone previous lumbar spine surgery were excluded from the study. The Oswestry Disability Index (ODI), which includes 10 sections, was used to assess the QOL. One-way analysis of variance was performed to determine the statistical relationship between radiographic LSS and ODI. Further, logistic regression analysis adjusted for gender, age, and body mass index was performed to detect the relationship. Results Complete data were available for 907 patients (300 men and 607 women; mean age, 67.3±12.4 years). The prevalence of severe, moderate, and non-mild/non-radiographic were 30%, 48%, and 22%, respectively. In addition, the mean values of ODI in each group were 12.9%, 13.1%, and 11.7%, respectively, and there was no statistically significant difference between the three groups in logistic analysis (P = 0.55). In addition, no significant differences in any section of the ODI were observed among the groups. However, severe radiographic LSS was associated with low back pain in the "severe" group as determined by logistic analysis adjusted for gender, age, and body mass index (odds ratio: 1.53, confidence interval: 1.13–2.07) compared with the non-severe group. Conclusion In this general population study, severe radiographic LSS was associated with low back pain (LBP), but did not affect ODI.

Introduction: Hip dislocation rates in patients with combined total hip arthroplasty (THA) and spinal deformity fixation are significantly higher than those of THA alone. Nevertheless, there are no treatment recommendations for patients who undergo THA and require a spine deformity correction later. Methods: Twenty-eight patients underwent spinal fixation surgery for adult spinal deformity. Sagittal spinopelvic alignment was analyzed on lateral radiographs taken preoperatively and postoperatively in the sitting and standing positions. Univariate linear regression analysis was conducted to identify the factors affecting the pelvic inclination in the sitting position after spinal fixation. Multiple regression analysis was conducted to determine the most efficient combination of radiographic parameters for predicting postoperative pelvic inclination while sitting. Results: There were significantly weak associations between postoperative sacral slope (SS) in the sitting position and the following factors: the number of vertebral levels fused (β = 0.30, p = 0.003); the presence of sacral fixation (β = 0.22, p = 0.01); the presence of sacroiliac joint fixation (β = 0.24, p = 0.008); and preoperative SS while standing and sitting (β = 0.21, p = 0.01 and β = 0.34, p = 0.001). Postoperative lumbar lordosis (LL) while standing was strongly associated with postoperative SS in the sitting position (β = 0.67, p

Rad51 drives DNA strand exchange, the central reaction in recombinational DNA repair. Two sites of Rad51 are responsible for DNA binding, but the function of these sites has proven elusive. Here, the authors employ real-time assays to reveal catalytic roles for the two DNA binding sites of Rad51.

Abstract Background Neurogenic origin intermittent claudication is typically caused by lumbar spinal canal stenosis. However, there are few reports of intermittent claudication caused by cervical spinal cord compression. Case presentation We present the case of a 75-year-old woman who presented with intermittent claudication. She had a history of lumbar spinal fusion surgery, but there was no sign of lumbar spinal stenosis. She also reported bilateral thigh pain on cervical extension. Electromyogram (EMG), posture-induced test, myelogram, and post-myelogram dynamic computed tomography (CT) were performed. Myelography and post-myelogram dynamic CT in the cervical extension position showed narrowing of the subarachnoid space; the patient reported pain in the front of the both thigh during the procedure. We performed an electromyogram (EMG), which implied neurogenic changes below the C5 level. Based on these results, we diagnosed cervical spinal cord compression and underwent laminoplasty at C4–6 including dome-like laminectomy, which significantly relieved the thigh pain and enabled her to walk for 40 minutes. Conclusions In this case, funicular pain presented as leg pain, but was resolved by the decompression of the cervical spinal cord. Funicular pain has various characteristics without any upper extreme symptom. This often leads to errors in diagnosis and treatment. We avoid the misdiagnosis by evaluating post-myelogram dynamic CT compared between flexion and extension. In cases of intermittent claudication, clinicians should keep in mind that cervical cord compression could be a potential cause.

Introduction: To carry out ultrasound-guided cervical nerve root block (CNRB) safely, we investigated the frequency of risky blood vessels around the target nerve root and within the imaginary needle pathway in the actual injecting position. Methods: 30 patients (20 men, 10 women) with cervical radiculopathy who received ultrasound-guided CNRB were included in this study. We defined a risky blood vessel as an artery existing within 4 mm from the center of the target nerve root or located in the range of 2 mm above or below the imaginary needle pathway. Results: Using the color Doppler method, the frequency of a risky blood vessel existing around 4 mm from the center of the C5 nerve root was 3.3% (1/30), whereas it was 3.3% (1/30) for the C6 nerve root and 23.3% (7/30) for the C7 nerve root. Hence, the C7 level had more blood vessels close to the target nerve root compared to the C5 and C6 levels, but there was no significant difference (p = 0.0523). On the other hand, the frequency of a risky blood vessel existing within 2 mm above and below the imaginary needle pathway was 3.3% (1/30) for the C5 nerve root, whereas it was 3.3% (1/30) for the C6 nerve root and 10.0% (3/30) for the C7 nerve root. The C7 level had more blood vessels within the needle pathway compared to the C5 and C6 levels, but there was no significant difference (p = 0.301). Conclusions: To reduce the risk of unintended intravascular injections, more careful checking for the presence or absence of blood vessels at the C7 level using color Doppler is necessary.

Accurate gluteus medius (GMd) volume evaluation may aid in the analysis of muscular atrophy states and help gain an improved understanding of patient recovery via rehabilitation. However, the segmentation of muscle regions in GMd images for cubic muscle volume assessment is time-consuming and labor-intensive. This study automated GMd-region segmentation from the computed tomography (CT) images of patients diagnosed with hip osteoarthritis using deep learning and evaluated the segmentation accuracy. To this end, 5250 augmented pairs of training data were obtained from five participants, and a conditional generative adversarial network was used to identify the relationships between the image pairs. Using the preserved test datasets, the results of automatic segmentation with the trained deep learning model were compared to those of manual segmentation in terms of the dice similarity coefficient (DSC), volume similarity (VS), and shape similarity (MS). As observed, the average DSC values for automatic and manual segmentations were 0.748 and 0.812, respectively, with a significant difference (p < 0.0001); the average VS values were 0.247 and 0.203, respectively, with no significant difference (p = 0.069); and the average MS values were 1.394 and 1.156, respectively, with no significant difference (p = 0.308). The GMd volumes obtained by automatic and manual segmentation were 246.2 cm3 and 282.9 cm3, respectively. The noninferiority of the DSC obtained by automatic segmentation was verified against that obtained by manual segmentation. Accordingly, the proposed GAN-based automatic GMd-segmentation technique is confirmed to be noninferior to manual segmentation. Therefore, the findings of this research confirm that the proposed method not only reduces time and effort but also facilitates accurate assessment of the cubic muscle volume.

Homologous recombination (HR) is essential for maintaining genome stability. Although Rad51 is the key protein that drives HR, multiple auxiliary factors interact with Rad51 to potentiate its activity. Here, we present an interdisciplinary characterization of the interactions between Rad51 and these factors. Through structural analysis, we identified an evolutionarily conserved acidic patch of Rad51. The neutralization of this patch completely abolished recombinational DNA repair due to defects in the recruitment of Rad51 to DNA damage sites. This acidic patch was found to be important for the interaction with Rad55-Rad57 and essential for the interaction with Rad52. Furthermore, biochemical reconstitutions demonstrated that neutralization of this acidic patch also impaired the interaction with Rad54, indicating that a single motif is important for the interaction with multiple auxiliary factors. We propose that this patch is a fundamental motif that facilitates interactions with auxiliary factors and is therefore essential for recombinational DNA repair.

Although Rad51 is the key protein in homologous recombination (HR), a major DNA double-strand break repair pathway, several auxiliary factors interact with Rad51 to promote productive HR. We present an interdisciplinary characterization of the interaction between Rad51 and Swi5-Sfr1, a conserved auxiliary factor. Two distinct sites within the intrinsically disordered N-terminus of Sfr1 (Sfr1N) were found to cooperatively bind Rad51. Deletion of this domain impaired Rad51 stimulation in vitro and rendered cells sensitive to DNA damage. By contrast, amino acid-substitution mutants, which had comparable biochemical defects, could promote DNA repair, suggesting that Sfr1N has another role in addition to Rad51 binding. Unexpectedly, the DNA repair observed in these mutants was dependent on Rad55-Rad57, another auxiliary factor complex hitherto thought to function independently of Swi5-Sfr1. When combined with the finding that they form a higher-order complex, our results imply that Swi5-Sfr1 and Rad55-Rad57 can collaboratively stimulate Rad51 in Schizosaccharomyces pombe.

Due to concerns over CO2 emissions and higher efficiency requirements future power generation systems with stationary gas turbines are projected to utilize carbon-free fuels such as ammonia and hydrogen at increasingly high pressure ratios and turbine inlet temperatures. This raises concerns whether conventional approaches for estimating the working fluid properties and for heat balance calculations are appropriate under such conditions. Herein, we therefore investigate the effect of several simplifying assumptions for the working fluid and the combustion scheme often made. We find that at high temperatures and equivalence ratios chemical reactions during the expansion of the gas should be considered, in particular at equivalence ratios close to unity. The extent to which chemical reactions occur during expansion in the turbine requires further investigations, as it could have severe consequences for the heat balances and output calculation of the turbine, as well as the concentration of pollutants such as NOx in the exhaust gas.

Mating-type switching in Schizosaccharomyces pombe entails programmed gene conversion events regulated by DNA replication, heterochromatin, and the HP1-like chromodomain protein Swi6. The whole mechanism remains to be fully understood. Using a gene deletion library, we screened ~ 3400 mutants for defects in the donor selection step where a heterochromatic locus, mat2-P or mat3-M, is chosen to convert the expressed mat1 locus. By measuring the biases in mat1 content that result from faulty directionality, we identified in total 20 factors required for donor selection. Unexpectedly, these included the histone H3 lysine 4 (H3K4) methyltransferase complex subunits Set1, Swd1, Swd2, Swd3, Spf1 and Ash2, the BRE1-like ubiquitin ligase Brl2 and the Elongator complex subunit Elp6. The mutant defects were investigated in strains with reversed donor loci (mat2-M mat3-P) or when the SRE2 and SRE3 recombination enhancers, adjacent to the donors, were deleted or transposed. Mutants in Set1C, Brl2 or Elp6 altered balanced donor usage away from mat2 and the SRE2 enhancer, towards mat3 and the SRE3 enhancer. The defects in these mutants were qualitatively similar to heterochromatin mutants lacking Swi6, the NAD+-dependent histone deacetylase Sir2, or the Clr4, Raf1 or Rik1 subunits of the histone H3 lysine 9 (H3K9) methyltransferase complex, albeit not as extreme. Other mutants showed clonal biases in switching. This was the case for mutants in the NAD+-independent deacetylase complex subunits Clr1, Clr2 and Clr3, the casein kinase CK2 subunit Ckb1, the ubiquitin ligase component Pof3, and the CENP-B homologue Cbp1, as well as for double mutants lacking Swi6 and Brl2, Pof3, or Cbp1. Thus, we propose that Set1C cooperates with Swi6 and heterochromatin to direct donor choice to mat2-P in M cells, perhaps by inhibiting the SRE3 recombination enhancer, and that in the absence of Swi6 other factors are still capable of imposing biases to donor choice.

OBJECTIVE:Patients with lumbar spinal stenosis (LSS) who have radiographically similar degrees of stenosis may not necessarily exhibit equivalent symptoms. As part of a cross-sectional study, we examined factors associated with symptomatic LSS (sLSS) in the general population of Japan. METHODS:We evaluated 968 participants (men, 319; women, 649) between 2008 and 2010. Orthopedic surgery specialists diagnosed sLSS using interview results, medical examinations, and imaging findings. LSS was radiographically graded using a 4-level scale. Additionally, we examined basic anthropometry, smoking habits, alcohol consumption, ankle-brachial index values (ABI), and glycosylated hemoglobin (HbA1c) levels. We grouped patients with moderate and severe radiographic LSS, and compared the indicated factors on the basis of the presence/absence of sLSS. Data were evaluated using multiple logistic regression analyses. RESULTS:Radiographically, 451 participants had moderate and 288 severe stenosis. Clinically, 92 participants were diagnosed with sLSS, including 36 with moderate and 52 with severe stenosis. In the moderate stenosis group, participants with sLSS had significantly higher rates of diabetes mellitus (DM) and lower ABIs than did non-LSS participants. Although sLSS participants tended to be older (p = 0.19), there were no significant differences in the sex distribution, body mass index values, or in the percentages of participants who were drinkers/smokers. In the severe stenosis group, there were no differences in any of the evaluated factors. Multiple logistic regression showed that DM (odds ratio [OR], 3.92; 95% confidence interval [CI], 1.52-9.34]) and low ABI (1 SD = 0.09; OR, 1.36; 95% CI, 1.04-1.81) were significantly associated with LSS in the moderate stenosis group. CONCLUSIONS:DM and low ABIs are significantly associated with sLSS in patients with moderate radiographic stenosis. Neither factor is associated with sLSS in patients with severe stenosis. Notably, the effects of intrinsic factors on symptomology may be masked when anatomic stenosis is severe.

Study DesignA retrospective study.PurposeTo examine the effectiveness of using an electrodiagnostic technique as a new approach in the clinical diagnosis of extraforaminal stenosis at L5-S1.Overview of LiteratureWe introduced a new effective approach to the diagnosis of extraforaminal stenosis at the lumbosacral junction using the existing electrophysiological evaluation technique.MethodsA consecutive series of 124 patients with fifth lumbar radiculopathy were enrolled, comprising a group of 74 patients with spinal canal stenosis and a second group of 50 patients with extraforaminal stenosis at L5-S1. The technique involved inserting a pair of needle electrodes into the foraminal exit zone of the fifth lumbar spinal nerves, which were used to provide electrical stimulation. The compound muscle action potentials from each of the tibialis anterior muscles were recorded.ResultsThe distal motor latency (DML) of the potentials ranged from 11.2 to 24.6 milliseconds in patients with extraforaminal stenosis. In contrast, the DML in patients with spinal canal stenosis ranged from 10.0 to 17.2 milliseconds. After comparing the DML of each of the 2 groups and at the same time comparing the differences in DML between the affected and unaffected side of each patient, we concluded there were statistically significant differences (p

Abstract.: Although acute treatment of pentamidine does not directly modify any ionic channel function in the heart at clinically relevant concentrations, its continuous exposure can prolong QT interval. Recent in vitro studies have indicated that hERG trafficking inhibition may play an important role in the onset of pentamidine-induced long QT syndrome. In this study, we examined acute in vivo electropharmacological effects of pentamidine using the halothane-anesthetized canine model (n = 5). The clinically relevant total dose of 4 mg/kg of pentamidine (namely, 1 mg/kg, i.v. over 10 min followed by 3 mg/kg, i.v. over 10 min with a pause of 20 min) decreased the mean blood pressure, ventricular contraction, preload to the left ventricle, and peripheral vascular resistance. Pentamidine also enhanced the atrioventricular conduction in parallel with its cardiohemodynamic actions, but it gradually prolonged both the ventricular repolarization period and effective refractory period, whereas no significant change was detected in the intraventricular conduction. Thus, acute administration of a clinically relevant dose of pentamidine can suppress cardiac function and vascular tone with reflex-mediated increase of sympathetic activity, whereas it may delay the repolarization process, suggesting that inhibition of potassium-channel trafficking might be induced more acutely In vivo than those previously expected in vitro. Keywords:: pentamidine, monophasic action potential, QT prolongation, torsades de pointes, trafficking

Abstract.: Pharmacokinetics of pilsicainide transdermal patch and its electropharmacological effects were simultaneously assessed using chronic atrioventricular block dogs. After application of the patch (9.8 mg/kg), pilsicainide was continuously absorbed through the skin with a Cmax of 0.49 ± 0.13 µg/ml, while its plasma concentration was kept above the clinically reported minimum effective plasma concentration for 2–8h. Inter-atrial conduction time was significantly prolonged, whereas statistically significant prolongation was not detected in the atrial effective refractory period. Prolongation of the cycle length of atrial fibrillation and antifibrillatory action were confirmed. Thus, pilsicainide can be absorbed transdermally to exert long-lasting electropharmacological effects leading to anti–atrial fibrillatory action. Keywords:: pilsicainide, transdermal delivery, atrial fibrillation

Fbh1, an F-box helicase related to bacterial UvrD, has been proposed to modulate homologous recombination in fission yeast. We provide several lines of evidence for such modulation. Fbh1, but not the related helicases Srs2 and Rqh1, suppressed the formation of crossover recombinants from single HO-induced DNA double-strand breaks. Purified Fbh1 in complex with Skp1 (Fbh1-Skp1 complex) inhibited Rad51-driven DNA strand exchange by disrupting Rad51 nucleoprotein filaments in an ATP-dependent manner; this disruption was alleviated by the Swi5-Sfr1 complex, an auxiliary activator of Rad51. In addition, the reconstituted SCFFbh1 complex, composed of purified Fbh1-Skp1 and Pcu1-Rbx1, displayed ubiquitin-ligase E3 activity toward Rad51. Furthermore, Fbh1 reduced the protein level of Rad51 in stationary phase in an F-box-dependent, but not in a helicase domain-independent manner. These results suggest that Fbh1 negatively regulates Rad51-mediated homologous recombination via its two putative, unrelated activities, namely DNA unwinding/translocation and ubiquitin ligation. In addition to its anti-recombinase activity, we tentatively suggest that Fbh1 might also have a pro-recombination role in vivo, because the Fbh1-Skp1 complex stimulated Rad51-mediated strand exchange in vitro after strand exchange had been initiated.

Purpose. Hypoglossal nerve palsy after use of the laryngeal mask airway (LMA) is an exceptionally rare complication. We present the first case of unilateral hypoglossal nerve palsy after use of the LMA Supreme. Clinical Features. A healthy 67-year-old female was scheduled for a hallux valgus correction under general anesthesia combined with femoral and sciatic nerve blocks. A size 4 LMA Supreme was inserted successfully at the first attempt and the cuff was inflated with air at an intracuff pressure of 60 cmH2O using cuff pressure gauge. Anesthesia was maintained with oxygen, nitrous oxide (67%), and sevoflurane under spontaneous breathing. The surgery was uneventful and the duration of anesthesia was two hours. The LMA was removed as the patient woke and there were no immediate postoperative complications. The next morning, the patient complained of dysarthria and dysphasia. These symptoms were considered to be caused by the LMA compressing the nerve against the hyoid bone. Conservative treatment was chosen and the paralysis recovered completely after 5 months. Conclusion. Hypoglossal nerve injury may occur despite correct positioning of the LMA under the appropriate intracuff pressure. A follow-up period of at least 6 months should be taken into account for the recovery.

Periosteal chondroma is a rare benign hyaline cartilage neoplasm that occurs most commonly in the metaphases of long tubular bones. We present a unique case of periosteal chondroma arising in the proximal phalanx of the left index finger in a 12-year-old boy. Physical examination revealed a slightly protuberant, subcutaneous mass. Plain radiographs and computed tomography scans showed a periosteal lesion producing saucerization of the cortex and subjacent cortical sclerosis, without internal matrix calcification. On magnetic resonance imaging, the lesion exhibited intermediate signal intensity on T1-weighted images and high signal intensity on T2-weighted images. Contrast-enhanced fat-suppressed T1-weighted images demonstrated peripheral and septal enhancement. The patient underwent a marginal excision with curettage of the underlying bone cortex. Histological examination confirmed the diagnosis of periosteal chondroma. There has been no evidence of local recurrence eight months after surgery. Periosteal chondroma can protrude into the subcutaneous soft tissue causing a palpable mass. Recognition of the typical radiological features can lead to an accurate diagnosis of this rare condition.

The objective of this study was to determine the point after sugammadex administration at which sufficient or insufficient dose could be determined, using first twitch height of train-of-four (T1 height) or train-of-four ratio (TOFR) as indicators. Groups A and B received 1 mg/kg and 0.5 mg/kg of sugammadex, respectively, as a first dose when the second twitch reappeared in train-of-four stimulation, and Groups C and D received 1 mg/kg and 0.5 mg/kg of sugammadex, respectively, as the first dose at posttetanic counts 1–3. Five minutes after the first dose, an additional 1 mg/kg of sugammadex was administered and changes in T1 height and TOFR were observed. Patients were divided into a recovered group and a partly recovered group, based on percentage changes in T1 height after additional dosing. T1 height and TOFR during the 5 min after first dose were then compared. In the recovered group, TOFR exceeded 90% in all patients at 3 min after sugammadex administration. In the partly recovered group, none of the patients had a TOFR above 90% at 3 min after sugammadex administration. An additional dose of sugammadex can be considered unnecessary if the train-of-four ratio is ≥90% at 3 min after sugammadex administration. This trial is registered with UMIN000007245.

Epithelioid sarcoma (ES) is a relatively rare, highly malignant soft tissue sarcoma. The mainstay of treatment is resection or amputation. Currently other therapeutic options available for this disease are limited. Therefore, a novel therapeutic option needs to be developed. In the present study, we established a new human ES cell line (ESX) and analyzed the characteristics of its cancer stem-like cells/cancer-initiating cells (CSCs/CICs) based on ALDH1 activity. We demonstrated that a subpopulation of ESX cells with high ALDH1 activity (ALDH(high) cells) correlated with enhanced clonogenic ability, sphere-formation ability, and invasiveness in vitro and showed higher tumorigenicity in vivo. Next, using gene expression profiling, we identified CD109, a GPI-anchored protein upregulated in the ALDH(high) cells. CD109 mRNA was highly expressed in various sarcoma cell lines, but weakly expressed in normal adult tissues. CD109-positive cells in ESX predominantly formed spheres in culture, whereas siCD109 reduced ALDH1 expression and inhibited the cell proliferation in vitro. Subsequently, we evaluated the expression of CD109 protein in 80 clinical specimens of soft tissue sarcoma. We found a strong correlation between CD109 protein expression and the prognosis (P = 0.009). In conclusion, CD109 might be a CSC/CIC marker in epithelioid sarcoma. Moreover, CD109 is a promising prognostic biomarker and a molecular target of cancer therapy for sarcomas including ES.

Condensin is required for chromosome dynamics and diverse DNA metabolism. How condensin works, however, is not well understood. Condensin contains two structural maintenance of chromosomes (SMC) subunits with the terminal globular domains connected to coiled-coil that is interrupted by the central hinge. Heterotrimeric non-SMC subunits regulate SMC. We identified a novel fission yeast SMC hinge mutant, cut14-Y1, which displayed defects in DNA damage repair and chromosome segregation. It contains an amino acid substitution at a conserved hinge residue of Cut14/SMC2, resulting in diminished DNA binding and annealing. A replication protein A mutant, ssb1-418, greatly alleviated the repair and mitotic defects of cut14-Y1. Ssb1 protein formed nucleolar foci in cut14-Y1 cells, but the number of foci was diminished in cut14-Y1 ssb1-418 double mutants. Consistent with the above results, Ssb1 protein bound to single-strand DNA was removed by condensin or the SMC dimer through DNA reannealing in vitro. Similarly, RNA hybridized to DNA may be removed by the SMC dimer. Thus, condensin may wind up DNA strands to unload chromosomal components after DNA repair and prior to mitosis. We show that 16 suppressor mutations of cut14-Y1 were all mapped within the hinge domain, which surrounded the original L543 mutation site.

Specialized chromatin exists at centromeres and must be precisely transmitted during DNA replication. The mechanisms involved in the propagation of these structures remain elusive. Fission yeast centromeres are composed of two chromatin domains: the central CENP-A(Cnp1) kinetochore domain and flanking heterochromatin domains. Here we show that fission yeast Mcl1, a DNA polymerase alpha (Pol alpha) accessory protein, is critical for maintenance of centromeric chromatin. In a screen for mutants that alleviate both central domain and outer repeat silencing, we isolated several cos mutants, of which cos1 is allelic to mcl1. The mcl1-101 mutation causes reduced CENP-A(Cnp1) in the central domain and an aberrant increase in histone acetylation in both domains. These phenotypes are also observed in a mutant of swi7(+), which encodes a catalytic subunit of Pol alpha. Mcl1 forms S-phase-specific nuclear foci, which colocalize with those of PCNA and Pol alpha. These results suggest that Mcl1 and Pol alpha are required for propagation of centromere chromatin structures during DNA replication.

In the fission yeast Schizosaccharomyces pombe, genetic evidence suggests that two mediators, Rad22 (the S. pombe Rad52 homolog) and the Swi5-Sfr1 complex, participate in a common pathway of Rhp51 (the S. pombe Rad51 homolog)-mediated homologous recombination (HR) and HR repair. Here, we have demonstrated an in vitro reconstitution of the central step of DNA strand exchange during HR. Our system consists entirely of homogeneously purified proteins, including Rhp51, the two mediators, and replication protein A (RPA), which reflects genetic requirements in vivo. Using this system, we present the first robust biochemical evidence that concerted action of the two mediators directs the loading of Rhp51 onto single-stranded DNA (ssDNA) precoated with RPA. Dissection of the reaction reveals that Rad22 overcomes the inhibitory effect of RPA on Rhp51-Swi5-Sfr1-mediated strand exchange. In addition, Rad22 negates the requirement for a strict order of protein addition to the in vitro system. However, despite the presence of Rad22, Swi5-Sfr1 is still essential for strand exchange. Importantly, Rhp51, but neither Rad22 nor the Swi5-Sfr1 mediator, is the factor that displaces RPA from ssDNA. Swi5-Sfr1 stabilizes Rhp51-ssDNA filaments in an ATP-dependent manner, and this stabilization is correlated with activation of Rhp51 for the strand exchange reaction. Rad22 alone cannot activate the Rhp51 presynaptic filament. AMP-PNP, a nonhydrolyzable ATP analog, induces a similar stabilization of Rhp51, but this stabilization is independent of Swi5-Sfr1. However, hydrolysis of ATP is required for processive strand transfer, which results in the formation of a long heteroduplex. Our in vitro reconstitution system has revealed that the two mediators have indispensable, but distinct, roles for mediating Rhp51 loading onto RPA-precoated ssDNA.