Effects of hip joint kinematics on the effective pelvis stiffness and hip impact force during simulated sideways falls

Improved understanding is required on how hip fracture risk is influenced by landing configuration. We examined how hip impact dynamics was affected by hip joint kinematics during simulated sideways falls. Twelve young adults (7 males, 5 females) of mean age 23.5 (SD = 1.5) years, participated in pelvis release experiments. Trials were acquired with the hip flexed 15° and 30° for each of three hip rotations: +15° ("external rotation"), 0°, and -15° ("internal rotation"). During falls, force-deformation data of the pelvis were recorded. Outcome variables included the peak hip impact force (Fexperimental) and effective stiffness of the pelvis (k1st, ksecant, and kms) determined with different methods suggested in literature, and predicted hip impact force during a fall from standing height (F1st, Fsecant and Fms). The two-way repeated-measures ANOVA was used to test whether these variables were associated with hip joint angles. The Fexperimental, ksecant and Fsecant were associated with hip rotation (F = 5.587, p = 0.005; F = 9.278, p < 0.0005; F = 5.778, p = 0.004, respectively), and 15 %, 31 % and 17 % smaller in 15° external than internal rotation (848 versus 998 N; 24.6 versus 35.6 kN/m; 2,637 versus 3,170 N, respectively). However, none of the outcome variables were associated with hip flexion (p > 0.05). Furthermore, there were no interactions between the hip rotation and flexion for all outcome variables (p > 0.05). Our results provide insights on hip impact dynamics, which may help improve a hip model to assess hip fracture risk during a fall.

Kinkless Electronic Junction along 1D Electronic Channel Embedded in a Van Der Waals Layer

Here, the formation of type-I and type-II electronic junctions with or without any structural discontinuity along a well-defined 1 nm-wide 1D electronic channel within a van der Waals layer is reported. Scanning tunneling microscopy and spectroscopy techniques are employed to investigate the atomic and electronic structure along peculiar domain walls formed on the charge-density-wave phase of 1T-TaS2 . Distinct kinds of abrupt electronic junctions with discontinuities of the band gap along the domain walls are found, some of which even do not have any structural kinks and defects. Density-functional calculations reveal a novel mechanism of the electronic junction formation; they are formed by a kinked domain wall in the layer underneath through substantial electronic interlayer coupling. This work demonstrates that the interlayer electronic coupling can be an effective control knob over nanometer-scale electronic property of 2D atomic monolayers.

Alternative Structure Model of Correlated Charge Density Wave in Monolayer 1T-Nb(Ta)Se2

The putative Mott charge density wave (CDW) phases of monolayer 1T-NbSe2 and 1T-TaSe2 have attracted a lot of recent interest due to the unexpected orbital texture of their Mott-Hubbard states and the superstructure related to an exotic possibility of a quantum spin liquid with a spinon Fermi surface. The origins of the orbital texture and the superstructure have been, however, elusive. We find by using density functional theory calculations that these CDW phases can have an alternative metastable structure, an anion (Se) centered cluster, in contrast to the prevailing model of a cation (Nb or Ta) centered David star cluster. This structure can be stabilized by the charge transfer from the bilayer graphene/SiC substrate used commonly in the experiments. The anion-centered structure has a similar electronic band structure of a charge transfer insulator to that of DS clusters but naturally explains the orbital texture of the upper Hubbard band from simply its atomic structure. Moreover, this band structure exhibits a Fermi surface nesting to possibly break the symmetry spontaneously into a 3 × 3 -R30° superstructure observed experimentally. The resulting ground state of the superstructure is shown to be a trivial band insulator, in contrast to exotic proposals. This result emphasizes the huge structural flexibility of these heteroexpitaxial monolayers, for which careful studies on atomic structures and interactions with substrates are highly requested.

Topological soliton molecule in quasi 1D charge density wave

Soliton molecules, bound states of two solitons, can be important for the informatics using solitons and the quest for exotic particles in a wide range of physical systems from unconventional superconductors to nuclear matter and Higgs field, but have been observed only in temporal dimension for classical wave optical systems. Here, we identify a topological soliton molecule formed spatially in an electronic system, a quasi 1D charge density wave of indium atomic wires. This system is composed of two coupled Peierls chains, which are endowed with a Z4 topology and three distinct, right-chiral, left-chiral, and non-chiral, solitons. Our scanning tunneling microscopy measurements identify a bound state of right- and left-chiral solitons with distinct in-gap states and net zero phase shift. Our density functional theory calculations reveal the attractive interaction of these solitons and the hybridization of their electronic states. This result initiates the study of the interaction between solitons in electronic systems, which can provide novel manybody electronic states and extra data-handling capacity beyond the given soliton topology.

Mobile Kink Solitons in a Van der Waals Charge-Density-Wave Layer

Kinks, point-like geometrical defects along dislocations, domain walls, and DNA, are stable and mobile, as solutions of a sine-Gordon wave equation. While they are widely investigated for crystal deformations and domain wall motions, electronic properties of individual kinks have received little attention. In this work, electronically and topologically distinct kinks are discovered along electronic domain walls in a correlated van der Waals insulator of 1T-TaS₂ . Mobile kinks and antikinks are identified as trapped by pinning defects and imaged in scanning tunneling microscopy. Their atomic structures and in-gap electronic states are unveiled, which are mapped approximately into Su-Schrieffer-Heeger solitons. The twelvefold degeneracy of the domain walls in the present system guarantees an extraordinarily large number of distinct kinks and antikinks to emerge. Such large degeneracy together with the robust geometrical nature may be useful for handling multilevel information in van der Waals materials architectures.

Blunted atrial reverse remodeling a year after catheter ablation for atrial fibrillation and their long-term rhythm outcome

Background

Although active rhythm control by atrial fibrillation (AF) catheter ablation (AFCA) reduces left atrial (LA) dimension, blunted atrial reverse remodeling can be observed in patients with significant atrial myopathy. We explored the characteristics and long-term outcomes of AF patients who showed blunted atrial reverse remodeling despite no AF recurrence within a year after AFCA.

Methods

Among a total of 2,756 patients with AFCA, we included 1,685 patients (74.8% male, 60.2±10.1 years old, 54.5% paroxysmal AF) who underwent both baseline and 1-year follow-up echocardiogram, baseline LA&gt;40mm, and did not recur within a year. We divided them into tertile groups (T1–T3) based on one-year percent change of LA dimension after propensity matching for age, sex, AF type, and baseline LA dimension. We also investigated the patients' genetic characteristics with blunted LA reverse remodeling (T1) using a genome-wide association study (GWAS).

Results

Patients with blunted LA reverse remodeling (T1, n=424) were independently associated with body mass index (OR 1.082 [1.010–1.160], p=0.025), LA peak pressure (OR 1.010 [1.002–1.019], p=0.019), LA wall thickness (OR 0.448 [0.252–0.789], p=0.006), LA voltage (OR 0.651 [0.463–0.907], p=0.012), and pericardial fat volume (OR 1.004 [1.001–1.008], p=0.014). Throughout 65.9±37.4 months of follow-up, the incidence of AF recurrence a year after the procedure was significantly higher in the T1 group than in T2 or T3 groups (Log-rank p&lt;0.001). Among 894 patients with GWAS, ATXN1, XPO7, KRR1_PHLDA1, ZFHX3, and their polygenic risk score were associated with blunted LA reverse remodeling.

Conclusions

Patients with blunted LA reverse remodeling after AFCA were independently associated with low LA voltage, thin wall thickness, high LA pressure, and fat volume, and have a genetic background. Long-term clinical recurrence a year after AFCA was higher in this patient group with suspicious atrial myopathy.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ministry of Health and WelfareNational Research Foundation of Korea

Z3 Charge Density Wave of Silicon Atomic Chains on a Vicinal Silicon Surface

An ideal one-dimensional electronic system is formed along atomic chains on Au-decorated vicinal silicon surfaces, but the nature of its low-temperature phases has been puzzling for last two decades. Here, we unambiguously identify the low-temperature structural distortion of this surface using high-resolution atomic force microscopy and scanning tunneling microscopy. The most important structural ingredient of this surface, the step-edge Si chains, are found to be strongly buckled, every third atom down, forming trimer unit cells. This observation is consistent with the recent model of rehybridized dangling bonds and rules out the antiferromagnetic spin ordering proposed earlier. The spectroscopy and electronic structure calculation indicate a charge density wave insulator with a Z₃ topology, making it possible to exploit topological phases and excitations. The tunneling current was found to substantially lower the energy barrier between three degenerate CDW states, which induces a dynamically fluctuating CDW at very low temperature.

Creation and annihilation of mobile fractional solitons in atomic chains

Localized modes in one-dimensional (1D) topological systems, such as Majonara modes in topological superconductors, are promising candidates for robust information processing. While theory predicts mobile integer and fractional topological solitons in 1D topological insulators, experiments so far have unveiled immobile, integer solitons only. Here we observe fractionalized phase defects moving along trimer silicon atomic chains formed along step edges of a vicinal silicon surface. By means of tunnelling microscopy, we identify local defects with phase shifts of 2π/3 and 4π/3 with their electronic states within the band gap and with their motions activated above 100 K. Theoretical calculations reveal the topological soliton origin of the phase defects with fractional charges of ±2e/3 and ±4e/3. Additionally, we create and annihilate individual solitons at desired locations by current pulses from the probe tip. Mobile and manipulable topological solitons may serve as robust, topologically protected information carriers in future information technology.

Engineering Domain Wall Electronic States in Strongly Correlated van der Waals Material of 1T-TaS2

Although a few physical methods were demonstrated for domain wall engineering in various electronic or ferroic materials with broken discrete symmetries, the direct control over the electronic properties of individual domain walls has been extremely limited. Here, we introduce a chemical method to tune the electronic property of domain walls in 1T tantalum disulfide. By using scanning tunneling microscopy and spectroscopy techniques, we find that indium adatoms on 1T-TaS₂ have distinct behaviors on the domains with different bulk terminations. Moreover, the adatoms form their own chains along the edges of neighboring domains. The density functional theory calculations reveal a 1D Mott insulating state on a modified domain wall, resulting from the degenerated spin-polarized bands with electron doping from adsorbates and charge transfer from neighboring domains. This work suggests that chemical decoration by adsorbates can be widely used to tune local electronic states of domain walls and various 2D materials.

Anterior resection syndrome: a randomized clinical trial of a 5-HT3 receptor antagonist (ramosetron) in male patients with rectal cancer

BACKGROUND

No effective treatment exists for anterior resection syndrome (ARS) following sphincter-saving surgery for rectal cancer. This RCT assessed the safety and efficacy of a 5-HT3 receptor antagonist, ramosetron, for ARS.

METHODS

A single-centre, randomized, controlled, open-label, parallel group trial was conducted. Male patients with ARS 1 month after rectal cancer surgery or ileostomy reversal were enrolled and randomly assigned (1 : 1) to 5 μg of ramosetron (Irribow®) daily or conservative treatment for 4 weeks. Low ARS (LARS) score was calculated after randomization and 4 weeks after treatment. The study was designed as a superiority test with a primary endpoint of the proportion of patients with major LARS between the groups. Primary outcome analysis was based on the modified intention-to-treat population. Safety was assessed by monitoring adverse events during the study.

RESULTS

: A total of 100 patients were randomized to the ramosetron (49 patients) or conservative treatment group (51 patients). Two patients were excluded, and 48 and 50 patients were analysed in the ramosetron and control groups, respectively. The proportion of major LARS after 4 weeks was 58 per cent (28 of 48 patients) in the ramosetron group versus 82 per cent (41 of 50 patients) in the control group, with a difference of 23.7 per cent (95 per cent c.i. 5.58 to 39.98, P = 0.011). There were minor adverse events in five patients, which were hard stool, frequent stool or anal pain. These were not different between the two groups. There were no serious adverse events.

CONCLUSION

: Ramosetron could be safe and feasible for male patients with ARS.

TRIAL REGISTRATION NUMBER

NCT02869984 (http://www.clinicaltrials.gov).

Sex differences in mapping and rhythm outcomes of a repeat atrial fibrillation ablation

Funding Acknowledgements

Type of funding sources: None.

Introduction

The risk of procedure-related complications and rhythm outcomes differ between men and women after atrial fibrillation catheter ablation (AFCA). We evaluated whether consistent sex differences existed in mapping and rhythm outcomes in repeat ablation procedures.

Methods

Among 3,282 patients in the registry, we analysed 443 consecutive patients (24.6% female, 58.5 ± 10.3 years old, 61.5% paroxysmal AF) who underwent a second AFCA. We compared the clinical factors, mapping, left atrial (LA) pressure, complications, and long-term clinical recurrences after propensity score matching.

Results

The LA volume index (43.1 ± 18.6 vs. 35.8 ± 11.6 ml/m2, p &lt; 0.001) was higher, but LA dimension (40.0 ± 6.8 vs. 41.6 ± 6.3mm, p = 0.018), LA voltage (0.94 ± 0.55 vs. 1.20 ± 0.68 mV, p = 0.002), and pericardial fat volume (89.5 ± 43.1 vs. 122.1 ± 53.9 cm3, p &lt; 0.001) lower in women with a repeat ablation than in their male counterparts. The pulmonary vein (PV) reconnections were lower (58.7% vs. 74.9%, p = 0.001), but the proportion of extra-PV triggers (27.5% vs. 17.0%, p = 0.026) and elevated LA pulse pressures (79.7% vs. 63.7%, p = 0.019) was significantly higher in women than men. There was no significant sex difference in the procedure-related complication rate (4.6% vs. 4.2%, p = 0.791). During a 31(8∼60) month median follow-up, clinical recurrences were significantly higher in women after both the de novo procedure (log rank p = 0.039, antiarrhythmic drug [AAD]-free log rank p &lt; 0.001) and second procedure (log rank p = 0.006, AAD-free log rank p = 0.093). A female sex (HR 1.51 [1.06-2.15], p = 0.023), non-paroxysmal AF (HR 1.78 [1.30-2.34], p &lt; 0.010), and extra-PV triggers (HR 1.88 [1.28-2.75], p = 0.001) were independently associated with clinical recurrences after repeat procedures.

Conclusions

During the repeat AFCA procedures, PV reconnections were lower in women than men, and the existence of extra-PV triggers and an LA pressure elevation was more significant, which resulted in poor rhythm outcomes.

Artificial intelligence-predicted poor responders to catheter ablation for atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Introduction

Although atrial fibrillation (AF) catheter ablation is effective for rhythm control, in some patients it is hard to maintain sinus rhythm in spite of repeated AF catheter ablation (AFCA) procedures and anti-arrhythmic drugs (AADs). We explored the pre-procedural predictors for poor responders to AFCA and tested whether artificial intelligence (AI) assists the prediction of poor responders in the independent cohort by determining the invasive parameters.

Methods

Among 1,214 patients who underwent AFCA and regular rhythm follow-up for 56.2 ± 33.8 months (59 ± 11 years, 73.5% male, 68.6% paroxysmal AF), we differentiated 92 poor responders defined as those with sustained AF despite repeat AFCAs, AADs, or electrical cardioversion. Using the Youden index, we identified advanced LA remodeling with lower LA voltage under 1.109mV. AI model, which was derived from development cohort using medical record, was applied to predict LA voltage &lt;1.109mV in the independent cohort (n = 634, poor responders = 24) using a grad-cam score.

Results

The patients with lower LA voltage under 1.109mV showed significantly poorer rhythm outcomes (Log-rank p &lt; 0.001). We determined invasive parameter LA voltage by using the multiple variables (age, female sex, AF type, CHA2DS2VASc score, LA dimension, E/em, hemoglobin, PR interval) and achieved relatively good prediction power of AI for LA voltage &lt;1.109mV (AUC = 0.734, sensitivity 0.729, specificity 0.643) in the test cohort. In the independent cohort, the AI model showed good discrimination power for poor responders (AUC 0.751, p &lt; 0.001) by estimating LA voltage, which is an invasive variable. The patients with predicted lower LA voltage (grad-cam score &lt;0) showed poorer rhythm outcome after active rhythm control (Log-rank p &lt; 0.001)

Conclusions

The patients with advanced atrial remodeling with low LA voltage, which can be predicted by an AI, showed significantly higher recurrence of AF after AFCA with AADs or cardioversion. AI may assist to select these poor responder patients before the AFCA procedure. Abstract Figure.

The reduction of body mass index and risk of incidence of cardiovascular events in the elderly population

Funding Acknowledgements

Type of funding sources: None.

Introduction

Obesity is known to be risk factor for incidence of cardiovascular (CV) events. However, the association between the reduction of body mass index (BMI) and incidence of cardiovascular event is not well established in elderly Asian population.

Methods

From the National Health Insurance Service-Senior (≥60 years) cohort from 2002 to 2013, 13,038 participants over 75 years old without baseline comorbidities (mean age: 78.4 ± 3.2 years 5243 (40.2%) male) were included in this study. We measured the change of BMI from first to second visit for health check-up within mean 23.6 ± 5.8months of follow-up. We categorized the reduction of BMI as five group according to the amount of change in BMI in overall patients (group 1: BMI change &lt;-10%, group 2: -10%≤BMI change&lt;-3%, group 3: -3% ≤ BMI change &lt; 3%, group 4: 3% ≤BMI change &lt; 10%, group 5: 10% ≤BMI change). We investigated the influence of change in BMI on the incidence of new-onset AF, stroke, acute myocardial infarction (MI), and CV mortality

Results

In the overall patients, new-onset AF, stroke, acute MI, and CV death was occurred in the 494 patients (3.5%), 775 patients (5.9%), 16 patients (0.1%), and 458 patients (3.5%) respectively. The Kaplan-Meier curve showed significant cumulative incidence rate of CV death in group 1 (Log rank p &lt; 0.001). The multivariate cox regression after adjusting for compound clinical covariates showed the risk of stroke (HR 1.43, 95% CI [1.09-1.89], p = 0.01) and CV death (HR 2.06, 95% CI [1.49-2.84] were significant higher in the group 1 as compared with group 3. In the high BMI (≥25) group, the risk of AF was significant higher in the group 5 as compared with group 3 (HR 2.38, 95% CI [1.02-5.54], p = 0.04). In contrast, the risk of stroke (HR 1.70, 95% CI [1.07-2.71], p = 0.02) and CV death (HR 3.27, 95% CI [1.66-6.41], p &lt; 0.001) was significant higher in the group 1 than in group 3.

Conclusions

In the elderly Asian population over 75 years old, the reduction of body weight affected worse effect on the incidence of stroke and CV death in overall patient and high BMI (≥25) group. It needs careful consideration to reduce BMI in the elderly Asian population even with high BMI (≥25) for purpose of CV events.

A study of the microbiological profile of filler-induced skin necrosis

Skin necrosis is one of the most severe complications following filler injections, and can result in permanent aesthetic defects. Although an increasing number of studies have addressed the management of dermal filler complications, no study has described the spectrum of microbial pathogens. The aim of this study was to delineate the bacterial profile and prognostic factors of filler-related skin necrosis by reviewing the clinical and microbiological features of these patients. A retrospective medical record review of patients undergoing treatment for skin necrosis induced by fillers was conducted. In total, 10 cases were identified, with injection sites being the nasolabial fold (70%; n = 7), nasal dorsum (20%; n = 2) and nasal tip (10%; n = 1). Reviewing the culture results, the true culture-positive rate was found to be 50% after cases of contamination were excluded. To avoid permanent sequelae, all physicians should be aware of possible secondary infections when treating filler-induced skin necrosis.

Timing and clinical outcomes of tracheostomy in patients with COVID-19

In this retrospective multicentre cohort study that included 27 COVID-19 patients who underwent tracheostomy, the mean time between intubation and tracheostomy was 15.8 days and the negative conversion time of COVID-19 was 43.1 days. Eleven patients (40.7%) died of COVID-19 and the use of percutaneous dilatation tracheostomy was significantly associated with in-hospital death. Timely tracheostomy could be performed in COVID-19 patients, regardless of duration of intubation or positivity of COVID-19 test, with an open surgical tracheostomy as a preferable technique.

Estrogen receptor alpha in the brain mediates tamoxifen-induced changes in physiology in mice

Adjuvant tamoxifen therapy improves survival in breast cancer patients. Unfortunately, long-term treatment comes with side effects that impact health and quality of life, including hot flashes, changes in bone density, and fatigue. Partly due to a lack of proven animal models, the tissues and cells that mediate these negative side effects are unclear. Here, we show that mice undergoing tamoxifen treatment experience changes in temperature, bone, and movement. Single-cell RNA sequencing reveals that tamoxifen treatment induces widespread gene expression changes in the hypothalamus and preoptic area (hypothalamus-POA). These expression changes are dependent on estrogen receptor alpha (ERα), as conditional knockout of ERα in the hypothalamus-POA ablates or reverses tamoxifen-induced gene expression. Accordingly, ERα-deficient mice do not exhibit tamoxifen-induced changes in temperature, bone, or movement. These findings provide mechanistic insight into the effects of tamoxifen on the hypothalamus-POA and indicate that ERα mediates several physiological effects of tamoxifen treatment in mice.

FAST: a randomised phase II study of zolbetuximab (IMAB362) plus EOX versus EOX alone for first-line treatment of advanced CLDN18.2-positive gastric and gastro-oesophageal adenocarcinoma

BACKGROUND

Claudin 18.2 (CLDN18.2) is contained within normal gastric mucosa epithelial tight junctions; upon malignant transformation, CLDN18.2 epitopes become exposed. Zolbetuximab, a chimeric monoclonal antibody, mediates specific killing of CLDN18.2-positive cells through immune effector mechanisms.

PATIENTS AND METHODS

The FAST study enrolled advanced gastric/gastro-oesophageal junction and oesophageal adenocarcinoma patients (aged ≥18 years) with moderate-to-strong CLDN18.2 expression in ≥40% tumour cells. Patients received first-line epirubicin + oxaliplatin + capecitabine (EOX, arm 1, n = 84) every 3 weeks (Q3W), or zolbetuximab + EOX (loading dose, 800 mg/m² then 600 mg/m² Q3W) (arm 2, n = 77). Arm 3 (exploratory) was added after enrolment initiation (zolbetuximab + EOX 1000 mg/m² Q3W, n = 85). The primary endpoint was progression-free survival (PFS) and overall survival (OS) was a secondary endpoint.

RESULTS

In the overall population, both PFS [hazard ratio (HR) = 0.44; 95% confidence interval (CI), 0.29-0.67; P < 0.0005] and OS (HR = 0.55; 95% CI, 0.39-0.77; P < 0.0005) were significantly improved with zolbetuximab + EOX (arm 2) compared with EOX alone (arm 1). This significant PFS benefit was retained in patients with moderate-to-strong CLDN18.2 expression in ≥70% of tumour cells (HR = 0.38; 95% CI, 0.23-0.62; P < 0.0005). Significant improvement in PFS was also reported in the overall population of arm 3 versus arm 1 (HR = 0.58; 95% CI, 0.39-0.85; P = 0.0114) but not in high CLDN18.2-expressing patients; no significant improvement in OS was observed in either population. Most adverse events (AEs) related to zolbetuximab + EOX (nausea, vomiting, neutropenia, anaemia) were grade 1-2. Grade ≥3 AEs showed no substantial increases overall (zolbetuximab + EOX versus EOX alone).

CONCLUSIONS

In advanced gastric/gastro-oesophageal junction and oesophageal adenocarcinoma patients expressing CLDN18.2, adding zolbetuximab to first-line EOX provided longer PFS and OS versus EOX alone. Zolbetuximab + EOX was generally tolerated and AEs were manageable. Zolbetuximab 800/600 mg/m² is being evaluated in phase III studies based on clinical benefit observed in the overall population and in patients with moderate-to-strong CLDN18.2 expression in ≥70% of tumour cells.

Systemic contact dermatitis induced by Rhus allergens in Korea: exercising caution in the consumption of this nutritious food

Systemic contact dermatitis (SCD) develops when a person who was previously sensitized to an allergen is exposed to the same allergen via the systemic route. In East Asia, the use of lacquer for polishing furniture is common and a part of the traditional culture. Contact exposure to tableware polished with Rhus lacquer may lead to sensitization. In Korea, SCD is commonly observed after systemic exposure to Rhus, a nutritious food item consumed because of the common belief of it improving the immune system. In this study, we reviewed the medical records of 21 Korean patients with SCD caused by Rhus ingestion. We found that the most significant epidemiological factor for SCD was the season of the year. Furthermore, 66.67% of the patients presented with leucocytosis and 23.81% showed increased liver enzyme levels. It is important to educate people on the risks associated with the systemic ingestion of Rhus.

Pseudogap and Weak Multifractality in 2D Disordered Mott Charge-Density-Wave Insulator

We investigate electronic states of Se-substituted 1T-TaS₂ by scanning tunneling microscopy/spectroscopy (STM/STS), where superconductivity emerges from the unique Mott-charge-density-wave (Mott-CDW) state. Spatially resolved STS measurements reveal that a pseudogap replaces the Mott gap with the CDW gaps intact. The pseudogap has little correlation with the unit-cell-to-unit-cell variation in the local Se concentration but appears globally. The correlation length of the local density of states (LDOS) is substantially enhanced at the Fermi energy and decays rapidly at high energies. Furthermore, the statistical analysis of LDOS indicates the weak multifractal behavior of the wave functions. These findings suggest a correlated metallic state induced by disorder and provide a new insight into the emerging superconductivity in two-dimensional materials.

Stable Flatbands, Topology, and Superconductivity of Magic Honeycomb Networks

We propose a new principle to realize flatbands which are robust in real materials, based on a network superstructure of one-dimensional segments. This mechanism is naturally realized in the nearly commensurate charge-density wave of 1T-TaS_{2} with the honeycomb network of conducting domain walls, and the resulting flatband can naturally explain the enhanced superconductivity. We also show that corner states, which are a hallmark of the higher-order topological insulators, appear in the network superstructure.

HELP-(Heparin-induced Extracorporeal LDL Precipitation)-apheresis in heart recipients with cardiac allograft vasculopathy and concomitant hypercholesterolemia: Influence of long-term treatment on the microcirculation

Hyperlipidemic heart transplant patients who develop cardiac allograft vasculopathy (CAV) benefit from HELP-apheresis (Heparin-induced Extracorporeal LDL Precipitation) which enables drastic lowering of plasma low-density lipoprotein, lipoprotein (a), and fibrinogen. There is evidence that HELP-apheresis also improves microcirculation by an immediate improvement of impaired endothelial-dependent vasodilatation and additive hemorheological effects.Therefore, cutaneous microcirculation was examined before, during, and after the first HELP-apheresis in eight hyperlipidemic cardiac transplant recipients with CAV. To study the long-term effect the intravital microscopy was repeated after three and 12 months of weekly apheresis treatment.In CAV patients the baseline mean erythrocyte velocity was pathologically reduced with 0.13±0.07 mm/s. During the first HELP-apheresis the erythrocyte velocity increased significantly (p = 0.0001) and remained increased until the end of the HELP procedure (p < 0.05). After three months of weekly apheresis treatment a decrease of temporary flow stops in the capillaries with a progressive homogenization (concordance) of the cutaneous microcirculation was observed. After one year of weekly treatment a markedly increase in mean erythrocyte velocity under resting conditions occurred. In addition, a reactive post-ischemic hyperemia could be established for the first time.Even the first single HELP-apheresis resulted in a significant improvement of the cutaneous microcirculation. The long-term treatment of these patients resulted in a marked improvement of the cutaneous microcirculation with the tendency to a normalization of the regulation of the capillary perfusion.

Correction to: CD4 T cell count is positively associated with lumbar spine bone mass in HIV-infected men under the age of 50 years

Two sentences in the Discussion section were incorrect.

Emergent honeycomb network of topological excitations in correlated charge density wave

When two periodic potentials compete in materials, one may adopt the other, which straightforwardly generates topological defects. Of particular interest are domain walls in charge-, dipole-, and spin-ordered systems, which govern macroscopic properties and important functionality. However, detailed atomic and electronic structures of domain walls have often been uncertain and the microscopic mechanism of their functionality has been elusive. Here, we clarify the complete atomic and electronic structures of the domain wall network, a honeycomb network connected by Z3 vortices, in the nearly commensurate Mott charge-density wave (CDW) phase of 1T-TaS2. Scanning tunneling microscopy resolves characteristic charge orders within domain walls and their vortices. Density functional theory calculations disclose their unique atomic relaxations and the metallic in-gap states confined tightly therein. A generic theory is constructed, which connects this emergent honeycomb network of conducting electrons to the enhanced superconductivity.

A multicentre, phase IIa study of zolbetuximab as a single agent in patients with recurrent or refractory advanced adenocarcinoma of the stomach or lower oesophagus: the MONO study

BACKGROUND

Claudin 18.2 (CLDN18.2) is physiologically confined to gastric mucosa tight junctions; however, upon malignant transformation, perturbations in cell polarity lead to CLDN18.2 epitopes being exposed on the cancer cell surface. The first-in-class monoclonal antibody, zolbetuximab (formerly known as IMAB362), binds to CLDN18.2 and can induce immune-mediated lysis of CLDN18.2-positive cells.

PATIENTS AND METHODS

Patients with advanced gastric, gastro-oesophageal junction (GEJ) or oesophageal adenocarcinomas with moderate-to-strong CLDN18.2 expression in ≥50% of tumour cells received zolbetuximab intravenously every 2 weeks for five planned infusions. At least three patients were enrolled in two sequential cohorts (cohort 1300 mg/m2; cohort 2600 mg/m2); additional patients were enrolled into a dose-expansion cohort (cohort 3600 mg/m2). The primary end point was the objective response rate [ORR: complete and partial response (PR)]; secondary end points included clinical benefit [ORR+stable disease (SD)], progression-free survival, safety/tolerability, and zolbetuximab pharmacokinetic profile.

RESULTS

From September 2010 to September 2012, 54 patients were enrolled (cohort 1, n = 4; cohort 2, n = 6; cohort 3, n = 44). Three patients in cohort 1 and 25 patients in cohorts 2/3 received at least 5 infusions. Antitumour activity data were available for 43 patients, of whom 4 achieved PR (ORR 9%) and 6 (14%) had SD for a clinical benefit rate of 23%. In a subgroup of patients with moderate-to-high CLDN18.2 expression in ≥70% of tumour cells, ORR was 14% (n = 4/29). Treatment-related adverse events occurred in 81.5% (n = 44/54) patients; nausea (61%), vomiting (50%), and fatigue (22%) were the most frequent.

CONCLUSIONS

Zolbetuximab monotherapy was well tolerated and exhibited antitumour activity in patients with CLDN18.2-positive advanced gastric or GEJ adenocarcinomas, with response rates similar to those reported for single-agent targeted agents in gastric/GEJ cancer trials.

CLINICALTRIALS.GOV NUMBER

NCT01197885.

Plasmid DNA nicking- a Novel Activity of Soybean Trypsin Inhibitor and Bovine Aprotinin

Protease inhibitors, such as trypsin inhibitor, serum alpha-1 antitrypsin, or liver aprotinin, are a class of proteins that competitively bind and block the catalytic activity of proteolytic enzymes with wide ranging biological functions. A significant number of protease inhibitors have also been shown to possess antimicrobial activity, presumed to contribute in defense against pathogenic microorganisms as plants with higher levels of protease inhibitors tend to exhibit increased resistance towards pathogens. Two proposed mechanisms for the antimicrobial activity are combating microbial proteases that play roles in disease development and disruption of microbial cell wall & membrane necessary for survival. Here we show for the first time a novel activity of soybean trypsin inhibitor and bovine aprotinin that they nick supercoiled, circular plasmid DNA. A number of experiments conducted to demonstrate the observed DNA nicking activity is inherent, rather than a co-purified, contaminating nuclease. The nicking of the plasmid results in markedly reduced efficiencies in transformation of E. coli and transfection of HEK293T cells. Thus, this work reveals yet a new mechanism for the antimicrobial activity by protease inhibitors.

CD4 T cell count is inversely associated with lumbar spine bone mass in HIV-infected men under the age of 50 years

HIV-infected men under the age of 50 years had a lower bone mass compared to that of HIV-uninfected men. Lower CD4 T cell counts, independent of whether antiretroviral therapy (ART) was used, were associated with lower BMD. HIV-infected patients with low CD4 T cell counts may need follow-up and intervention regarding bone health, including younger patients.

INTRODUCTION

HIV-infected patients have a low bone mineral density (BMD) owing to multifactorial interaction between common osteoporosis risk factors and HIV-related factors, including chronic inflammation and ART. Although HIV infection and ART might affect bone metabolism, little data is available for patients aged under 50 years. We aimed to investigate the association of HIV infection-induced low CD4 T cell counts and ART with BMD in men aged under 50 years.

METHODS

We performed an age- and body mass index-matched case-control study. BMD values of HIV-infected and HIV-uninfected men (< 50 years) were compared, and HIV-infected men were stratified by CD4 T cell counts and ART use.

RESULTS

After adjusting confounders, HIV-infected men with CD4 T cell counts ≥ 500 cells/μL (n = 28) and < 500 cells/μL (n = 139) had lower BMD at the femoral neck (FN, p < 0.001) and total hip (TH, p < 0.001) than HIV-uninfected men (n = 167). HIV-infected men with CD4 T cell counts < 500/μL had lower BMD at the lumbar spine (LS, p = 0.034) than those with counts of ≥ 500 cells/μL, but not at FN and TH. The CD4 T cell count (γ = 0.169, p = 0.031) was positively correlated with BMD at LS. There was no significant difference in the BMD (p = 0.499-> 0.999) between the ART-naïve (n = 75) and ART-user group (n = 92).

CONCLUSIONS

Despite their relatively younger age, HIV-infected men had a lower BMD than HIV-uninfected men. Lower CD4 T cell counts, irrespective of ART, might result in lower bone mass.

Abstract P2-14-01: The impact of local therapy on locoregional recurrence in women with high risk breast cancer in the neoadjuvant I-SPY2 TRIAL

Background: In women with breast cancer receiving neoadjuvant chemotherapy, residual cancer burden (RCB) predicts distant recurrence and survival. In those with high risk tumors, locoregional recurrence (LRR) remains a concern, and has been associated with type of local therapy received. We evaluated the impact of local therapy on LRR in the ISPY-2 TRIAL.

Methods: Data were analyzed in Stata 14.2, using Chi2 test, log rank test, and a Cox proportional hazards model. RCB was considered a categorical variable (0/1 versus 2/3), as described in prior publications. Breast surgery categories were lumpectomy +/- radiotherapy, or mastectomy +/- radiotherapy. Axillary surgery was defined as sentinel lymph node (SLN) surgery (≤6 nodes removed) or axillary dissection (&gt;6 nodes).

Results: Follow up data from the I-SPY2 TRIAL were available for 630 patients (median follow up 2.76 yrs, range 0.4-7.2). Type of local therapy was significantly associated with clinical stage at presentation, with stage III patients most frequently undergoing mastectomy + radiation (p&lt;0.001). Women with higher RCB were more likely to undergo mastectomy than those with lower RCB (61.3% vs 48.8% mastectomy rate, p=0.002), and more likely to receive adjuvant radiotherapy (62.0% vs 53.9%, p=0.048). There was no association between clinical stage, type of surgery, or radiotherapy and LRR (Table). Higher RCB was significantly associated with LRR, with 3 year locoregional recurrence free rate of 95.1% in RCB 0/1 versus 89.9% in RCB 2/3 (p=0.003).

In a Cox model adjusting for clinical stage, tumor subtype, surgical therapy, RCB status, nodal radiation, and age, significant predictors for LRR were tumor subtype and RCB status. Hazard ratio (HR) for LRR in those with RCB 0/1 was 0.39 compared to those with RCB 2/3 (95% CI 0.17-0.87, p=0.021). There was no difference in LRR between breast conservation and mastectomy; within the breast conservation group, those who had lumpectomy alone had higher hazard of LRR compared to those having lumpectomy + radiation (HR 3.1, 95% CI 1.1-9.2, p=0.043).

Conclusions: Extent of surgical therapy was not associated with local tumor control, regardless of advanced tumor stage at presentation. Rather, tumor biology and response to therapy were the best predictors of LRR. These data highlight the opportunity to minimize the morbidity of extensive surgical therapy for patients with excellent response to systemic therapy.

LRR rates by clinical features and treatment status FrequencyLRR RateP valueClinical Stage  0.5I240 (47.5%)5.8% II185 (36.6%)8.7% III80 (15.8%)6.3% Tumor Subtype  0.014ER+PR+Her2-161 (26.4%)3.1% ER+PR-Her2-56 (9.2%)3.6% Her2+176 (28.9%)6.3% Triple negative216 (35.5%)11.1% Local therapy  0.169Lumpectomy85 (13.5%)11.8% Lumpectomy with radiation198 (31.4%)5.6% Mastectomy173 (27.5%)5.2% Mastectomy with radiation174 (27.6%)8.6% Axillary surgery  0.23None5 (0.8%)20% SLN329 (52.2%)5.8% ALND296 (47%)8.5% Axillary radiation  0.535Yes42 (6.7%)9.5% No588 (93.3%)7.0% Axillary management  0.2No surgery or radiation5 (0.8%)20.0% SLN312 (50%)5.3% SLN+Axillary radiation17 (2.7%)8.3% ALND271 (43%)10.3% ALND+Axillary radiation25 (4%)5.4% RCB  0.0020/1293 (50.1%)3.8% 2/3292 (49.9%)10.3% 

Citation Format: Silverstein J, Suleiman L, Yau C, Price ER, Singhrao R, Yee D, DeMichele A, Isaacs C, Albain KS, Chien AJ, Forero-Torres A, Wallace AM, Pusztai L, Ellis ED, Elias AD, Lang JE, Lu J, Han HS, Clark AS, Korde L, Nanda R, Northfelt DW, Khan QJ, Viscusi RK, Euhus DM, Edmiston KK, Chui SY, Kemmer K, Wood WC, Park JW, Liu MC, Olopade O, Leyland-Jones B, Tripathy D, Moulder SL, Rugo HS, Schwab R, Lo S, Helsten T, Beckwith H, I-SPY 2 TRIAL Consortium, Berry DA, Asare SM, Esserman LJ, Boughey JC, Mukhtar RA. The impact of local therapy on locoregional recurrence in women with high risk breast cancer in the neoadjuvant I-SPY2 TRIAL [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-14-01.

Abstract P2-07-03: Refining neoadjuvant predictors of three year distant metastasis free survival: Integrating volume change as measured by MRI with residual cancer burden

Background: Patients achieving a pathologic complete response (pCR) following neoadjuvant therapy have significantly improved event-free survival relative to those who do not; and pCR is an FDA-accepted endpoint to support accelerated approval of novel agents/combinations in the neoadjuvant treatment of high risk early stage breast cancer. Previous studies have shown that recurrence risk increased with increasing burden of residual disease (as assessed by the RCB index). As well, these studies suggest that patients with minimum residual disease (RCB-I class) also have favorable outcomes (comparable to those achieving a pCR) within high risk tumor subtypes. In this study, we assess whether integrating RCB with MRI functional tumor volume (FTV), which in itself is prognostic, can improve prediction of distant recurrence free survival (DRFS); and identify a subset of patients with minimal residual disease with comparable DRFS as those who achieved a pCR. Imaging tools can then be used to identify the subset that will do well early and guide the timing of surgical therapy.

Method: We performed a pooled analysis of 596 patients from the I-SPY2 TRIAL with RCB, pre-surgical MRI FTV data and known follow-up (median 2.5 years). We first assessed whether FTV predicts residual disease (pCR or pCR/RCB-I) using ROC analysis. We applied a power transformation to normalize the pre-surgical FTV distribution; and assessed its association with DRFS using a bi-variate Cox proportional hazard model adjusting for HR/HER2 subtype. We also fitted a bivariate Cox model of RCB index adjusting for subtype; and assessed whether adding pre-surgical FTV to this model further improves association with DRFS using a likelihood ratio (LR) test. For the Cox modeling, penalized splines approximation of the transformed FTV and RCB index with 2 degrees of freedom was used to allow for non-linear effects of FTV and RCB on DRFS.

Result: Pre-surgical MRI FTV is significantly associated with DRFS (Wald p&lt;0.00001), and more effective at predicting pCR/RCB-I than predicting pCR alone (AUC: 0.72 vs. 0.65). Larger pre-surgical FTV remains associated with worse DRFS adjusting for subtype (Wald p &lt;0.00001). The RCB index is also significantly associated with DRFS adjusting for subtype (Wald p&lt;0.00001). Adding FTV to a model containing RCB and subtype further improves association with DRFS (LR p=0.0007). RCB-I patients have excellent DRFS (94% at 3 years compared to 95% in the pCR group). Efforts are underway to identify an optimal threshold for dichotomizing pre-surgical FTV and FTV change measures for use in combination with pCR/RCB-I class to generate integrated RCB (iRCB) groups as a composite predictor of DRFS.

Conclusion: Pre-surgical MRI FTV is effective at predicting minimal residual disease (RCB0/I) in the I-SPY 2 TRIAL. Despite the association between FTV and RCB, FTV appears to provide independent added prognostic value (to RCB and subtype), suggesting that integrating MRI volume measures and RCB into a composite predictor may improve DRFS prediction.

Citation Format: Hylton NM, Symmans WF, Yau C, Li W, Hatzis C, Isaacs C, Albain KS, Chen Y-Y, Krings G, Wei S, Harada S, Datnow B, Fadare O, Klein M, Pambuccian S, Chen B, Adamson K, Sams S, Mhawech-Fauceglia P, Magliocco A, Feldman M, Rendi M, Sattar H, Zeck J, Ocal I, Tawfik O, Grasso LeBeau L, Sahoo S, Vinh T, Yang S, Adams A, Chien AJ, Ferero-Torres A, Stringer-Reasor E, Wallace A, Boughey JC, Ellis ED, Elias AD, Lang JE, Lu J, Han HS, Clark AS, Korde L, Nanda R, Northfelt DW, Khan QJ, Viscusi RK, Euhus DM, Edmiston KK, Chui SY, Kemmer K, Wood WC, Park JW, Liu MC, Olopade O, Tripathy D, Moulder SL, Rugo HS, Schwab R, Lo S, Helsten T, Beckwith H, Haugen PK, van't Veer LJ, Perlmutter J, Melisko ME, Wilson A, Peterson G, Asare AL, Buxton MB, Paoloni M, Clennell JL, Hirst GL, Singhrao R, Steeg K, Matthews JB, Sanil A, Berry SM, Abe H, Wolverton D, Crane EP, Ward KA, Nelson M, Niell BL, Oh K, Brandt KR, Bang DH, Ojeda-Fournier H, Eghtedari M, Sheth PA, Bernreuter WK, Umphrey H, Rosen MA, Dogan B, Yang W, Joe B, I-SPY 2 TRIAL Consortium, Yee D, Pusztai L, DeMichele A, Asare SM, Berry DA, Esserman LJ. Refining neoadjuvant predictors of three year distant metastasis free survival: Integrating volume change as measured by MRI with residual cancer burden [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-07-03.

Abstract P3-01-02: Detection of circulating tumor cells (CTC) in blood and disseminated tumor cells (DTC) in bone marrow at surgery identifies breast cancer patients (pts) with long-term risk of distant recurrence and breast cancer-specific death

We examined the prognostic impact of CTCs and DTCs detected at the time of definitive surgery in pts diagnosed with early breast cancer (EBC).

Methods: Blood and bone marrow samples from 742 treatment-naïve EBC pts, not eligible for neoadjuvant therapy, were collected immediately prior to surgery. 87% were hormone receptor (HR)-positive, and 71% were node-negative. DTCs (n=584) were enumerated using an EPCAM-based method involving immunomagnetic enrichment and flow cytometry (IE/FC). CTCs were enumerated either by IE/FC (n=288) or CellSearch (n=380). Optimal cutoffs for CTC-/DTC-positivity were selected using Monte-Carlo cross validation. Multivariate Cox regression analysis was performed to determine correlation between levels of CTCs/DTCs vs. distant recurrence-free survival (DRFS) and breast cancer-specific survival (BCSS). The overall median follow-up was 7.1 years for DRFS and and 9.1 years for BCSS, but extended up to 13.3 years in subset analyses (Table 1).

Results: CTC-positivity by CellSearch was associated with HER2-positivity (Fisher p=0.01). Using optimized cutoffs in multivariate analyses, we found that CTC-positive pts by CellSearch had a statistically significant increased risk of distant recurrence (HR 4.93, p=0.0067). Moreover, pts who were CTC-positive by IE/FC had a statistically significant increased risk of breast cancer-specific death (HR=3.54, p=0.0138). DTC status, by itself, was not prognostic; however, when combined with CTC status by IE/FC (n=273), positive detection for both (CTC+DTC+) was significantly associated with increased risk of distant recurrence (HR=3.09, p=0.0270) and breast cancer-specific death (HR=4.55, p=0.0205).

Table 1.Multivariate analysis to determine the prognostic significance of CTCs and DTCs detected at the time of surgery in treatment naive early breast cancer patients. Adjusted for age at diagnosis, tumor size, pathologic stage, HR and HER2 status, node status and grade.  DRFS  BCSS  Variable and Method% positiveHR [95% CI]Wald p-valueMedian f/u [range] Years*HR [95% CI]Wald p-valueMedian f/u [range] Years*CTC+ vs. CTC- by CellSearch94.93[1.56-15.6]0.00676.4 [0.16-13.8]4.50[0.76-26.5]0.09627.5 [0.71-15.0]CTC+ vs. CTC- by IE/FC401.92[0.93-3.95]0.07599.8 [0.09-18.5]3.54[1.29-9.72]0.013813.3 [1.93-18.5]DTC+ vs. DTC- by IE/FC181.46[0.75-2.81]0.26317.5 [0.09-18.5]1.48[0.64-3.42]0.35429.8 [1.55-18.5]CTC+DTC+ vs. CTC-DTC- by IE/FC8**3.09[1.14-8.40]0.02709.8 [0.09-18.5]4.55[1.26-16.39]0.020513.3 [1.93-18.5]*f/u - follow-up; **double positive

Conclusions: We demonstrate the impact of quantitative evaluation of CTCs and DTCs by IE/FC. Our large single institution dataset, in which CTCs and DTCs have been contemporaneously quantitated, has the longest patient follow-up. Simultaneous detection of CTCs and DTCs at the time of definitive surgery in treatment naïve EBC pts is an independent prognostic factor associated with increased long-term risk of distant recurrence and death due to breast cancer. Given the lack of early endpoints for low-risk patients, liquid biopsy may be an important consideration for future studies.

Citation Format: Magbanua MJM, Yau C, Wolf D, Lee JS, Chattopadhyay A, Scott JH, Yoder E, Hwang S, Alvarado M, Ewing CA, Delson AL, van't Veer L, Esserman L, Park JW. Detection of circulating tumor cells (CTC) in blood and disseminated tumor cells (DTC) in bone marrow at surgery identifies breast cancer patients (pts) with long-term risk of distant recurrence and breast cancer-specific death [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-01-02.

Abstract P4-01-12: Low peripheral blood CD4/CD8 ratio at the time of surgery is a negative long-term prognostic factor in women with early stage breast cancer

It is hypothesized that cancer prognosis may be related to the functional status of the immune system. We examined the correlation between peripheral blood CD4/CD8 ratio measured at the time of surgery and clinical outcome in patients diagnosed with early stage breast cancer.

Patient and Methods

Peripheral blood from 57 treatment-naïve early breast cancer patients, not eligible for neoadjuvant chemotherapy, was collected on the day of definitive surgery. CD4+ and CD8+ T cells were enumerated using flow cytometry and the ratio between the two immune cell populations was calculated. Cox regression analyses were performed to determine the relationship between CD4/CD8 ratio vs. distant disease-free survival (DRFS), breast cancer-specific survival (BCSS) and overall survival (OS). The median follow-up times were 10.1 years (range: 0.4-17.5) and 15.0 (range: 1.0-18.5) for DRFS and BCSS/OS, respectively.

Results

The patients' mean age at diagnosis was 54 years old (range: 31-78). 82% were hormone receptor-positive, 21% HER2-positive, and 61% node-negative. The median CD4/CD8 ratio was 2; and a ratio ≤ 2 was considered low. CD4/CD8 ratio was not associated with any of the clinicopathologic variable examined. Multivariate analysis using a survival model that adjusted for potential confounding factors (age, tumor size, grade, stage, hormone receptor, HER2, lymph-node status) revealed that patients with low CD4/CD8 ratio have statistically significant increased risk of distant recurrence (DRFS HR 5.3, Wald p=0.0381) and death (OS HR 3.8 Wald p=0.0271).

Conclusions

Immune dysfunction at the time surgery is correlated with long-term increased risk for metastatic recurrence and death. Larger clinical studies are warranted to confirm the results of this study.

Citation Format: Magbanua MJM, Yau C, Scott JH, van't Veer L, Park JW, Esserman L, Campbell M. Low peripheral blood CD4/CD8 ratio at the time of surgery is a negative long-term prognostic factor in women with early stage breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-01-12.

Evaluation of the Microshear Bond Strength of MDP-containing and Non-MDP-containing Self-adhesive Resin Cement on Zirconia Restoration

OBJECTIVES

The purpose of this study was to measure the microshear bond strength (μSBS) of four different self-adhesive resin cements with/without 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-containing primer to zirconium ceramics and to evaluate the effect of zirconia primers on these self-adhesive resin cements (SARCs).

METHODS AND MATERIALS

Zirconia blocks (20 × 20 × 8 mm³) were prepared and divided into eight groups (n=20). They were sandblasted (50 μm Al₂O₃) and treated as follows: no primer or primer (Z-Primer Plus). Four self-adhesive resin cements (MDP-containing: Permacem 2.0 [PC], Clearfil SA luting [CS]; non-MDP-containing: Rely-X U200 [RU], Maxcem Elite [ME]) were bonded to the zirconia surface. After thermocycling, a μSBS test was performed. The failure mode was analyzed using light microscopy. Statistical analysis of μSBS was performed using one-way analysis of variance and two-sample t-test with post hoc Tukey test. The loss rate was evaluated using the Fisher's exact test and χ² test with post hoc Tukey test (p<0.05).

RESULTS

Within the no primer groups, the PC and CS groups showed higher bond strength than the RU and ME groups. Comparing the μSBS of the no primer and primer groups in the same SARCs, the RU/P group was higher than the RU group, and the ME/P group was higher than the ME group. No significant difference was observed between the PC and PC/P groups and between the CS and CS/P groups.

CONCLUSIONS

Non-MDP-containing SARC showed the increased bonding value with MDP-containing primer to zirconia ceramics. The bond strength of MDP-containing SARCs was not affected significantly by the use of zirconia primer.

Dosimetric analysis of stereotactic rotational versus static intensity-modulated radiation therapy for pancreatic cancer

PURPOSE

Stereotactic body radiation therapy is a promising treatment modality for locally advanced pancreatic cancer. To determine the optimal radiation treatment, we compared the plan characteristics of volumetric-modulated arc therapy and intensity-modulated radiation therapy when administered with stereotactic body radiation therapy to treat pancreatic cancer.

PATIENTS AND METHODS

Fifteen patients with locally advanced pancreatic cancer were treated by stereotactic body radiation therapy at a dose of 24-32Gy in four fractions with marker-guided gated volumetric-modulated arc therapy. Four dimensional-computed tomography scans were used to assess the target and surrounding normal organs. The same images, contours, and dose constraints were used for dual-arc volumetric-modulated arc therapy and 9-field intensity-modulated radiation therapy planning. Plans were compared using dosimetric parameters and treatment performance.

RESULTS

Volumetric-modulated arc therapy required significantly lower monitor units (1726 vs. 4188; P<0.001) and shorter treatment delivery time in comparison with intensity-modulated radiation therapy (22.5min vs. 52.4min; P<0.001). Regarding target volume coverage, both modalities demonstrated comparable results (V_95%, 99.3% vs. 99.4%; P=0.796). Both modalities satisfied the dosimetric determinants for duodenal toxicity and the maximum and mean doses administered to normal organ were also statistically similar.

CONCLUSION

In comparison with 9-field intensity-modulated radiation therapy, volumetric-modulated arc therapy significantly reduces the number of monitoring units and treatment delivery times while administering similar dosimetric quality. Based on these results, volumetric-modulated arc therapy might be an appropriate treatment for locally advanced pancreatic cancer when combined with stereotactic body radiation therapy.

Seven-year Follow-up of Resin Infiltration Treatment on Noncavitated Proximal Caries

The purpose of this case report is to present success and failure outcomes of seven-year follow-up of resin infiltration treatment (RIT) used for the proximal caries of maxillary premolars. Although resin infiltration can be a good option for micro-invasive treatment, long-term follow-up data are not sufficient, and the outcome of this technique can be affected by factors such as technique sensitivity of procedure, patient's caries risk, and depth of caries progression. Therefore, careful case selection, application, and follow-up are needed.

Loss of XBP1 accelerates age-related decline in retinal function and neurodegeneration

Background

Aging is the strongest risk factor for neurodegenerative diseases and extended age results in neuronal degeneration and functional decline in the visual system. Among many contributing factors to age-related deterioration of neurons is an insufficient activation of the Unfolded Protein Response (UPR) in the endoplasmic reticulum (ER) in response to cellular stress. X-box binding protein 1 (XBP1) is a major component of the UPR and is essential for maintaining protein homeostasis and reducing cellular stresses. Herein, we investigate the role of XBP1 in maintaining morphological and functional integrity in retinal neurons during adulthood and the early stages of aging.

Methods

The basal and induced levels of XBP1 activation in the retina were measured in young adult and aged mice. Conditional knockout (cKO) of XBP1 in retinal neurons was achieved by crossing XBP1 floxed mice with a retina specific Cre-recombinase line (Chx10-Cre). Retinal morphology, neuronal populations including photoreceptors, bipolar cells, and retinal ganglion cells (RGCs), synaptic structure, and microglial activation were examined with immunohistochemistry and staining of retinal sections. Retinal function was evaluated with light-adapted (photopic) and dark adapted (scotopic) electroretinograms. Retinal mitochondrial function and metabolism was assessed by Seahorse XF^e24 Extracellular Flux Analyzer.

Results

The retinas of aged wild type (WT) mice display a significantly reduced basal level of Xbp1s and compromised activation of ER stress response. In XBP1 cKO mice, significant structural degeneration of the retina, evidenced by thinning of retinal layers and a loss of RGCs, and functional defects indicated by diminished photopic and scotopic ERG b-waves are observed at the age of 12–14 months. Furthermore, discontinuous and disorganized synaptic laminae, colocalized with activated microglia, in the inner plexiform layer is found in the XBP1 cKO retinas. In addition, cKO mice demonstrate a significant increase in ectopic synapses between bipolar cells and photoreceptors, which is strikingly similar to WT mice at 20–24 months of age. These changes are associated with defective retinal glycolysis while mitochondrial respiratory function appears normal in the cKO retina.

Conclusions

XBP1 cKO mice at 12–14 months of age show significant structural, functional, and metabolic deficits that closely resemble WT mice twice that age. Our findings suggest that the absence of XBP1, a critical component of the UPR, accelerates age-related retinal neurodegeneration.

Electronic supplementary material

The online version of this article (10.1186/s13024-018-0250-z) contains supplementary material, which is available to authorized users.

Abstract P2-01-01: Trajectory patterns of circulating tumor cells (CTC) in chemotherapy-treated metastatic breast cancer (MBC) patients predict poor clinical outcomes: CALGB 40502 (Alliance)/NCCTG N063H study

Little is known about the dynamics of CTCs during treatment and its clinical significance. We examined the predictive utility of serial CTC analysis in ER+HER2- MBC patients (pts) treated with chemotherapy in the CALGB 40502/NCCTG N063H study, a randomized phase III trial of weekly paclitaxel compared to weekly nanoparticle albumin bound nab-paclitaxel or ixabepilone +/- bevacizumab as first-line therapy (ClinicalTrials.gov Identifier: NCT00785291, Support: U10CA180821, U10CA180882).

Methods: Of the 783 pts treated, 469 had ≥3 serial blood samples (including baseline) successfully analyzed for CTCs by CellSearch® and were included in this analysis (n=2,202). Samples with ≥5 CTCs per 7.5 mLs of blood were considered CTC+. The prognostic and predictive performance of baseline CTCs (bCTC) and CTC status from baseline to cycle 2 (b2CTC) were compared to a novel latent mixture model classification based on trajectory of CTCs (tCTC). Akaike Information Criterion (AIC) was used to select the model (bCTC vs b2CTC vs tCTC) that best predicts overall survival (OS), progression-free survival (PFS), and time-to-treatment failure (TTF).

Results: 53% of the pts were CTC+ at baseline. b2CTC status changed in 36% of the pts, most of whom were CTC+CTC- (35%), and very few CTC-CTC+ (1%); the rest of the pts did not experience a change in b2CTC status (46% CTC-CTC- and 19% CTC+CTC+). Mixture model analysis revealed 4 groups of pts that show distinct tCTC patterns over the course of treatment: consitently very low/undectectable CTCs (tCTCneg, 56%), low (tCTClo, 24%), intermediate (tCTCmid, 15%), or high (tCTChi, 5%). bCTC, b2CTC, and tCTC were significantly correlated with tumor subtype (all p &lt;0.0022) and presence of bone metastasis (all p &lt;0.0001). Multivariate analysis showed that pts who were CTC+ at baseline, and those whose b2CTC status remained positive (CTC+CTC+) had significantly reduced OS, PFS and TTF.

 OSPFSTTFModelsHR (95% CI)p-valueHR (95% CI)p-valueHR (95% CI)p-valuebCTC (vs CTC-)      → CTC+2.5(1.8-3.3)&lt;0.00011.6(1.3-2.0)&lt;0.00011.3(1.1-1.6)0.0046b2CTC (vs CTC+CTC-)      → CTC-CTC+1.6(0.5-5.4)0.41491.6(0.6-4.5)0.39051.6(0.6-4.3)0.3961→ CTC+CTC+2.7(1.9-3.8)&lt;0.00011.8(1.4-2.5)&lt;0.00011.8(1.3-2.4)&lt;0.0001→ CTC-CTC-0.5(0.4-0.8)0.00020.8(0.6-0.9)0.01600.9(0.7-1.1)0.2771tCTC (vs tCTCneg)      → tCTClo2.6(1.9-3.7)&lt;0.00011.9(1.4-2.4)&lt;0.00010.9(0.7-1.1)0.0033→ tCTCmid5.3(3.6-8.0)&lt;0.00012.5(1.8-3.4)&lt;0.00011.8(1.4-2.5)0.0001→ tCTChi10.8(6.1-19)&lt;0.00013.0(1.8-5.0)&lt;0.00012.3(1.4-3.7)0.0009CTC- (&lt;5 CTCs per 7.5 mLs); CTC+ (≥5 CTCs per 7.5 mLs)

Pts with tCTClo, tCTCmid and tCTChi had significantly shorter OS, PFS and TTF compared to those with tCTCneg. After adjustment for potential confounders, AIC analysis revealed that the tCTC model best predicts OS and PFS, while b2CTC best predicts TTF.

 AIC Score*ModelsOSPFSTTFbCTC243240514199b2CTC240540384186tCTC237940264188*The lowest AIC score indicates the best model.

Conclusions: Analysis of CTC trajectory patterns identified pts with poor outcome who could potentially benefit from more effective treatment. Validation in independent cohorts is warranted to confirm the findings in this study.

Citation Format: Magbanua MJ, Hendrix L, Hyslop T, Barry WT, Winer EP, Hudis C, Toppmeyer D, Burnstein H, Qadir M, Ma C, Scott JH, Park JW, Rugo HS. Trajectory patterns of circulating tumor cells (CTC) in chemotherapy-treated metastatic breast cancer (MBC) patients predict poor clinical outcomes: CALGB 40502 (Alliance)/NCCTG N063H study [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-01-01.

Lunate morphology as a risk factor of idiopathic ulnar impaction syndrome

AIMS

Positive ulnar variance is an established risk factor for idiopathic ulnar impaction syndrome (UIS). However, not all patients with positive ulnar variance develop symptomatic UIS and other factors, including the morphology of the lunate, may be involved. The aim of this study was to clarify the relationship between lunate morphology and idiopathic UIS.

PATIENTS AND METHODS

A cohort of 95 patients with idiopathic UIS (UIS group) was compared with 95 asymptomatic controls with positive ulnar variance. The shape of the lunate was measured using the capitate-triquetrum distance (CTD), ulnar coverage ratio (UCR), radiolunate distance and radiolunate angle. The association of radiographic parameters and lunate types with the development of UIS was investigated in univariable and multivariable analyses. Receiver operating characteristic curves were used to estimate a cutoff for any statistically significant variables.

RESULTS

The proportion of type II lunates, which have a medial hamate facet, were significantly higher in the UIS group than in the control group in the univariable analysis (p = 0.001). CTD (odds ratio (OR) 1.52; 95% confidence interval (CI) 1.11 to 2.06; p = 0.008) and UCR (OR 44.78; 95% CI 5.35 to 374.90; p = 0.002) showed a positive association with UIS in the multivariable analysis. Estimated cutoff values were 2.5 mm for the CTD (area under the curve (AUC) = 0.65) and 0.4 for the UCR (AUC = 0.64).

CONCLUSION

The proportion of type II lunates was greater in the UIS group than in the control group. A large UCR, which represents the broad base of the lunate, was positively associated with the development of idiopathic UIS. Cite this article: Bone Joint J 2017;99-B:1508-14.

Use of metal/metal oxide spherical cluster and hydroxyl metal coordination complex for descriptor calculation in development of nanoparticle cytotoxicity classification model

Computational approaches have been suggested as an informative tool for risk assessment of nanomaterials. Nano (quantitative) structure-activity relationship, nano-(Q)SAR, models have been developed to predict toxicity of metal oxide (MOx) nanoparticles (NPs); however, the packing structure and cluster of nanoparticle have been included for the descriptor calculation in only two studies. This study proposed spherical cluster and hydroxyl metal coordination complex to calculate descriptors for development of nanoparticle cytotoxicity classification model. The model cluster was generated from metal (M) or MOx crystal structure to calculate physicochemical properties of M/MOx NPs and the hydroxyl metal coordination complex was used to calculate the properties of the metal cation in an aqueous environment. Data were collected for 2 M and 19 MOx NPs in human bronchial epithelial cell lines and murine myeloid cell lines at 100 μg/ml after 24 hours exposure. The model was developed with scaled HOMO energy of the model cluster and polarizability of the hydroxyl metal coordination complex, as reactivity of the particles and the cations explained cause of cytotoxic action by M/MOx NPs. As the developed model achieved 90.31% accuracy, the classification model in this work can be used for virtual screening of toxic action of M/MOx NPs.

Low appendicular muscle mass is associated with mortality in peritoneal dialysis patients: a single-center cohort study

BACKGROUND/OBJECTIVES

There are few studies of the association between low appendicular muscle mass (LAM) and clinical outcomes in peritoneal dialysis (PD) patients. We aimed to determine the clinical association between LAM and clinical outcomes in PD patients.

SUBJECT/METHODS

We reviewed all PD patients who underwent PD between January 2001 and April 2014. Each patient's appendicular lean mass was estimated using dual-energy X-ray absorptiometry. The appendicular muscle mass index (AMI) was calculated using total appendicular lean mass (kg) over body mass index (kg/m²). The cut-off AMI value for LAM was <0.789 for men and <0.512 for women.

RESULTS

The number of patients in the Non-LAM and LAM groups was 328 and 303, respectively. The median follow-up durations in the Non-LAM and LAM groups were 47 and 49 months, respectively. The numbers of deaths in the Non-LAM and LAM groups were 96 (29.3%) and 160 (52.8%), respectively. In a comparison with the Non-LAM group, the hazard ratio in the LAM group was 1.74 (95% confidence interval (CI), 1.35-2.24) in univariate and 1.71 (95% CI, 1.28-2.26) in multivariate Cox regression analysis. In addition, the hazard ratio for a 0.1 increase in baseline AMI was 0.89 (95% CI, 0.84-0.95) in univariate analysis and 0.84 (95% CI, 0.76-0.91) in multivariate analysis. Analyses using the 1-year AMI showed trends similar to those for the initial AMI.

CONCLUSIONS

Our study showed the association of LAM with mortality in the incident PD patients.

Prediction of local control in early glottic carcinoma using the maximum standardised uptake value

PURPOSE

This retrospective study aimed to determine whether the maximum standardised uptake value (SUV_max) can predict local tumour control in early glottic cancer (Tis, T1, and T2).

PATIENTS AND METHODS

Fifty-nine patients treated with definitive radiotherapy for early glottic cancer between 2003 and 2011 were enrolled. We evaluated the SUV_max in the region of interest around the original tumour site. Local tumour control and survival were estimated using Kaplan-Meier curves. Receiver operating characteristic curves were used to assess the optimal SUV_max cut-off for predicting local control.

RESULTS

As determined by laryngoscopy, all patients achieved a complete response. Eleven patients experienced local recurrence, while no distant metastasis occurred. One patient died due to local recurrence, while five lost their larynxes. The median follow-up was 61.5 (range: 6.2-123.4) months. The five-year local progression-free survival was 84.7%, and larynx preservation was possible in 89.6% of cases. The median SUV_max was 2.2. The optimal SUV_max for predicting local tumour control was identified as 3.4. Patients with glottic cancers with an SUV_max>3.4 showed a significantly lower local progression-free survival rate than those with tumours with an SUV_max<3.4 (five-year local progression-free survival rate: 53.4% vs. 95.4%, P<0.01). Multivariate analysis confirmed that a high SUV_max was an independent predictive factor for local progression-free survival (P=0.006).

CONCLUSION

The use of (¹⁸F)-fluorodeoxyglucose-positron emission tomography for evaluation of the SUV_max is useful to predict local progression-free survival in patients with early glottic cancer treated by radiation. Early glottic cancer with a high SUV_max may require aggressive local treatment and careful surveillance.

Effect of Insufficient Light Exposure on Polymerization Kinetics of Conventional and Self-adhesive Dual-cure Resin Cements

Objectives: The purpose of this study was to investigate the influence of insufficient light exposure on the polymerization of conventional and self-adhesive dual-cure resin cements under ceramic restorations.

Methods: Two conventional dual-cure resin cements (Rely-X ARC, Duolink) and two self-adhesive resin cements (Rely-X U200, Maxcem Elite) were polymerized under different curing modes (dual-cure or self-cure), curing times (20 and 120 seconds), and thickness of a ceramic overlay (2 and 4 mm). Polymerization kinetics was measured by Fourier transform infrared spectroscopy for the initial 10 minutes and after 24 hours. Data were analyzed using mixed model analysis of variance (ANOVA), one-way ANOVA/Student-Newman-Keuls post hoc test, and paired t-test (α=0.05).

Results: When light-curing time was set to 20 seconds, the presence of the ceramic block significantly affected the degree of conversion (DC) of all resin cements. Especially, the DC of the groups with 20 seconds of light-curing time under 4 mm of ceramic thickness was even lower than that of the self-cured groups at 24 hours after polymerization (p&lt;0.05). However, when light-curing time was set to 120 seconds, a similar DC compared with the group with direct light exposure (p&gt;0.05) was achieved in all dual-cure groups except Maxcem Elite, at 24 hours after polymerization.

Conclusions: For both conventional and self-adhesive dual-cure resin cements, insufficient light exposure (20 seconds of light-curing time) through thick ceramic restoration (4 mm thick) resulted in a DC even lower than that of self-curing alone.