Transmission of foreshock waves through Earth's bow shock.

The Earth's magnetosphere and its bow shock, which is formed by the interaction of the supersonic solar wind with the terrestrial magnetic field, constitute a rich natural laboratory enabling in situ investigations of universal plasma processes. Under suitable interplanetary magnetic field conditions, a foreshock with intense wave activity forms upstream of the bow shock. So-called 30 s waves, named after their typical period at Earth, are the dominant wave mode in the foreshock and play an important role in modulating the shape of the shock front and affect particle reflection at the shock. These waves are also observed inside the magnetosphere and down to the Earth's surface, but how they are transmitted through the bow shock remains unknown. By combining state-of-the-art global numerical simulations and spacecraft observations, we demonstrate that the interaction of foreshock waves with the shock generates earthward-propagating, fast-mode waves, which reach the magnetosphere. These findings give crucial insight into the interaction of waves with collisionless shocks in general and their impact on the downstream medium.

The Importance of Nitrate Reduction for Oral Health.

Salivary glands concentrate plasma nitrate into saliva, leading to high nitrate concentrations that can reach the millimolar range after a nitrate-rich vegetable meal. Whereas human cells cannot reduce nitrate to nitrite effectively, certain oral bacteria can. This leads to an increase in systemic nitrite that can improve conditions such as hypertension and diabetes through nitric oxide availability. Apart from systemic benefits, it has been proposed that microbial nitrate reduction can also promote oral health. In this review, we discuss evidence associating dietary nitrate with oral health. Oral bacteria can reduce nitrite to nitric oxide, a free radical with antimicrobial properties capable of inhibiting sensitive species such as anaerobes involved in periodontal diseases. Nitrate has also been shown to increase resilience against salivary acidification in vivo and in vitro, thus preventing caries development. One potential mechanism is proton consumption during denitrification and/or bacterial reduction of nitrite to ammonium. Additionally, lactic acid (organic acid involved in oral acidification) and hydrogen sulfide (volatile compound involved in halitosis) can act as electron donors for these processes. The nitrate-reducing bacteria Rothia and Neisseria are consistently found at higher levels in individuals free of oral disease (vs. individuals with caries, periodontitis, and/or halitosis) and increase when nitrate is consumed in clinical studies. Preliminary in vitro and clinical evidence show that bacteria normally associated with disease, such as Veillonella (caries) and Prevotella (periodontal diseases and halitosis), decrease in the presence of nitrate. We propose nitrate as an ecologic factor stimulating eubiosis (i.e., an increase in health-associated species and functions). Finally, we discuss the preventive and therapeutic potential, as well as safety issues, related to the use of nitrate. In vivo evidence is limited; therefore, robust clinical studies are required to confirm the potential benefits of nitrate reduction on oral health.

Evaluation of Color-matching Ability of a Structural Colored Resin Composite.

PURPOSE: The present study evaluated the color-matching ability of a structural colored resin composite to compare it with resin composites employing pigments. METHODS AND MATERIALS: A structural colored resin composite (Omnichroma [OMC]), a supranano-filled resin composite (Estelite ∑ Quick [ELQ]), and a nano-filled resin composite (Filtek Supreme Ultra [FSU]) were used. Each resin composite was packed into a Teflon mold and pressed down with a clear strip under a glass slide. The specimens were light irradiated through the slide with a light-emitting diode curing unit. The thickness of the specimens (n=6) was measured with a digital caliper before being transferred to distilled water and stored at 37°C for 24 hours. The measurements of the optical characteristics of the specimens on a black-and-white background were performed using a spectrophotometer. D65 (CIE D65) was used as a light source for the spectrophotometer. Measurements were repeated three times for each specimen under each color-measurement condition, and average values for three same-shade specimens were calculated. One-way analysis of variance and Tukey post hoc tests were used (α=0.05). To determine its ability to match the color of artificial teeth, each shade of resin composite was placed in a cavity before performing color measurements. Using a spectrophotometer (CMS-35F S/C) with a flexible sensor, L*, a*, and b* values were obtained. RESULTS: The spectral reflectance curve of OMC showed that it reflected light wavelengths from 430-700 nm regardless of the background color and thickness of the specimens. The percentage of reflectance of ELQ decreased near wavelengths of 550-580 nm. Regarding the influence of background color on CIE L*, a*, b* values, the L* level showed significantly higher values for all tested materials with white backgrounds, and OMC was most affected by the difference in background color. However, a* values of ELQ and FSU were significantly higher with a black background than with a white background, and OMC showed a significantly higher value with a white background than with a black background. The b* values were higher with a white background than with a black background and were significantly higher for all three products, and these tendencies were much greater for ELQ and FSU. CONCLUSIONS: The ability of OMC to match the color of artificial teeth showed acceptable color compatibility, regardless of the shade of the artificial teeth and the depth of the cavity. However, ELQ and FSU showed reduced color compatibility, especially for a cavity depth of 3.0 mm. Excellent color matching ability was confirmed for the structural colored resin composite OMC, resulting in reduced color differences and therefore improving the esthetic appearance of the restoration, simplifying shade matching, and compensating for any color mismatch.

CTV-to-PTV margin assessment for esophageal cancer radiotherapy based on an accumulated dose analysis.

PURPOSE: This study aimed to assess the smallest clinical target volume (CTV) to planned target volume (PTV) margins for esophageal cancer radiotherapy using daily online registration to the bony anatomy that yield full dosimetric coverage over the course of treatment. METHODS: 29 esophageal cancer patients underwent six T2-weighted MRI scans at weekly intervals. An online bone-match image-guided radiotherapy treatment of five fractions was simulated for each patient. Multiple conformal treatment plans with increasing margins around the CTV were created for each patient. Then, the dose was warped to obtain an accumulated dose per simulated fraction. Full target coverage by 95% of the prescribed dose was assessed as a function of margin expansion in six directions. If target coverage in a single direction was accomplished, then the respective margin remained fixed for the subsequent dose plans. Margins in uncovered directions were increased in a new dose plan until full target coverage was achieved. RESULTS: The smallest set of CTV-to-PTV margins that yielded full dosimetric CTV coverage was 8 mm in posterior and right direction, 9 mm in anterior and cranial direction and 10 mm in left and caudal direction for 27 out of 29 patients. In two patients the curvature of the esophagus considerably changed between fractions, which required a 17 and 23 mm margin in right direction. CONCLUSION: Accumulated dose analysis revealed that CTV-to-PTV treatment margins of 8, 9 and 10 mm in posterior & right, anterior & cranial and left & caudal direction, respectively, are sufficient to account for interfraction tumor variations over the course of treatment when applying a daily online bone match. However, two patients with extreme esophageal interfraction motion were insufficiently covered with these margins and were identified as patients requiring replanning to achieve full target coverage.

Patients triaged to neoadjuvant chemotherapy have higher rates of sarcopenia: An opportunity for prehabilitation.

OBJECTIVE: To compare baseline body composition measures (BCM), including sarcopenia, between patients with advanced epithelial ovarian cancer (EOC) undergoing primary cytoreductive surgery (PCS) versus neoadjuvant chemotherapy/interval cytoreductive surgery (NACT/ICS) and evaluate changes in BCM pre-NACT versus pre-ICS. METHODS: Patients with stage IIIC/IV EOC who underwent PCS or NACT with curative intent between 1/1/2012 and 7/31/2016 were included. Computed tomography scans were evaluated via a semi-automated program to determine BCM. Measures evaluated include skeletal muscle area (SMA), skeletal muscle density (SMD), skeletal muscle index (SMI), and skeletal muscle gauge (SMG). Sarcopenia was defined as SMI <39.0 cm2/m2. RESULTS: The study included 200 PCS patients and 85 NACT/ICS patients, of which 76 had both pre-NACT and pre-ICS scans. NACT patients were significantly more likely to be sarcopenic compared to PCS patients (40.0% vs 27.5%, p = 0.04). Mean SMA (107.3 vs 113.4 cm2, p = 0.004) and mean SMG (1344.6 vs. 1456.9 (cm2 x HU)/m2, p = 0.06) were lower in NACT patients. Among NACT/ICS patients, mean SMI significantly decreased -1.4 cm2/m2 (p = 0.005) at the time of surgery, resulting in a non-statistically significant increase in the percentage of sarcopenic patients from baseline (40.8% vs. 50.0%, p = 0.09). CONCLUSIONS: Sarcopenia is more common in patients with advanced EOC undergoing NACT compared to PCS when using an evidence-based triage system for triage decisions. Body composition changes significantly over the course of NACT. Sarcopenia may be an indicator of debility and another factor for consideration in treatment planning. Further research into body composition's effects on prognosis and altering sarcopenia is necessary.

Establishment of normative biometric data for body composition based on computed tomography in a North American cohort.

BACKGROUND & AIMS: Accurate and reproducible biomarkers are required to allow a more personalized approach to patient care. Body composition is one such biomarker affecting outcomes in a range of surgical and oncological conditions. The aim of this study is to determine the age and sex specific distribution of body composition data, based on information gathered from computed tomography (CT). METHODS: This prospective study used healthy subjects from the medical records linkage of the Rochester Epidemiology Project, based in Minnesota, USA. Each patient had a CT scan without intravenous contrast performed between 1999 and 2001. Quantification was performed using previously validated semi-automated in-house developed software for body composition analysis. Subcutaneous adipose tissue area, visceral adipose tissue area, intermuscular adipose tissue area and skeletal muscle area were measured and indexed to subject height. Generalized Additive Models for Location, Scale and Shape were used to assess the location, scale, and shape of each variable across age, stratified by sex. Z-scores specific to sex were assessed for each of the parameters analyzed. Age-specific z-scores were calculated using the formula: Z = (Index Variable - µ)/σ or Z = (√ (Index Variable) - µ)/σ. RESULTS: There were 692 subjects enrolled in the study. The fitted model equation was offered for each variable with values presented for µ and σ. Modelling with penalized splines was performed for VAT index, IMAT index and total adipose tissue index. Scatterplots of each variable were produced with lines of Z-scores as a visual representation. CONCLUSION: This study offers comparative data to allow comparison amongst multiple populations. This will form an important reference for future research and clinical practice.

Intermittent pneumatic compression versus additional prophylaxis with enoxaparin for prevention of venous thromboembolism after laparoscopic surgery for gastric and colorectal malignancies: multicentre randomized clinical trial.

BACKGROUND: The role of antithrombotic chemoprophylaxis in prevention of venous thromboembolism (VTE) in laparoscopic surgery for gastric and colorectal malignancies is unknown. This study compared the addition of enoxaparin following intermittent pneumatic compression (IPC) with IPC alone in patients undergoing laparoscopic surgery for gastrointestinal malignancy. METHODS: In this multicentre RCT, eligible patients were older than 40 years and had a WHO performance status of 0 or 1. Exclusion criteria were prescription of antiplatelet or anticoagulant drugs and history of VTE. Patients were allocated to IPC or to ICP with enoxaparin in a 1 : 1 ratio. Stratification factors included sex, location of cancer, age 61 years and over, and institution. Enoxaparin was administered on days 1-7 after surgery. Primary outcome was VTE, evaluated by multidetector CT on day 7. RESULTS: Of 448 patients randomized, 208 in the IPC group and 182 in the IPC with enoxaparin group were evaluated. VTE occurred in ten patients (4·8 per cent) in the IPC group and six (3·3 per cent) in the IPC with enoxaparin group (P = 0·453). Proximal deep vein thrombosis and/or pulmonary embolism occurred in seven patients (3·4 per cent) in the IPC group and one patient (0·5 per cent) in the IPC with enoxaparin group (P = 0·050). All VTE events were asymptomatic and non-fatal. Bleeding occurred in 11 of 202 patients in the IPC with enoxaparin group, and one patient needed a transfusion. All bleeding events were managed by discontinuation of the drug. CONCLUSION: IPC with enoxaparin after laparoscopic surgery for gastric and colorectal malignancies did not reduce the rate of VTE. Registration number: UMIN000011667 ( https://www.umin.ac.jp/).

ANTECEDENTES: El papel de la quimioprofilaxis para la prevención del tromboembolismo venoso (venous thromboembolism, VTE) en la cirugía laparoscópica de los tumores malignos gástricos y colorrectales se desconoce. El objetivo de este estudio fue comparar la quimioprofilaxis antitrombótica (enoxaparina) y la compresión neumática intermitente (intermittent pneumatic compression, IPC) en pacientes sometidos a cirugía laparoscópica de tumores malignos abdominales. MÉTODOS: Se efectuó un ensayo aleatorizado, controlado y multicéntrico de pacientes sometidos a cirugía laparoscópica de tumores gástricos y colorrectales en Japón. Los criterios de inclusión eran pacientes mayores de 40 años de edad y con un estado funcional de WHO de 0-1. Los criterios de exclusión fueron la prescripción al paciente de fármacos antiagregantes o anticoagulantes y la historia de VTE. Los pacientes fueron asignados a IPC y ICP con la adición de enoxaparina en una relación 1:1. Los factores de estratificación incluyeron el sexo, la localización del cáncer, la edad mayor o menor de 61 años, y la institución. La enoxaparina fue administrada en los días postoperatorios (postoperative day, POD) 1-7. El resultado primario fue la VTE evaluada mediante tomografía computarizada multidetector en el POD7. Los cálculos de la potencia determinaron que se requerían 184 pacientes en cada grupo. RESULTADOS: De los 448 pacientes aleatorizados, se evaluaron finalmente 208 pacientes en el grupo IPC y 182 pacientes en el grupo IPC más enoxaparina. La VTE ocurrió en 10 de 208 pacientes en el grupo IPC (4,8%) y 6 de 182 pacientes en el grupo IPC más enoxaparina (3,3%) (P = 0,45). La trombosis venosa profunda proximal (proximal deep vein thrombosis, DVT) y/o el embolismo pulmonar (pulmonary embolism, PE) ocurrieron en 7 de 208 pacientes en el grupo IPC (3,4%) y 1 de 182 pacientes en el grupo IPC más enoxaparina (0,55%) (riesgo relativo 0,163, i.c. del 95% 0,020-1,314, P = 0,0503). Todos los eventos de VTE fueron asintomáticos y no mortales. Se produjo una hemorragia en 11 de 202 pacientes en el grupo IPC con enoxaparina (5,4%, i.c. del 95% 3,1%-9,5%, P < 0,001), y un paciente precisó transfusión. Todos los eventos hemorrágicos pudieron ser tratados con la interrupción del fármaco. CONCLUSIÓN: La IPC con la adición de enoxaparina tras cirugía laparoscópica de los tumores malignos gástricos y colorrectales no disminuye la VTE.

3-Dimensional target coverage assessment for MRI guided esophageal cancer radiotherapy.

PURPOSE: This study aimed to quantify the coverage probability for esophageal cancer radiotherapy as a function of a preset margin for online MR-guided and (CB)CT-guided radiotherapy. METHODS: Thirty esophageal cancer patients underwent six T2-weighted MRI scans, 1 prior to treatment and 5 during neoadjuvant chemoradiotherapy at weekly intervals. Gross tumor volume (GTV) and clinical target volume (CTV) were delineated on each individual scan. Follow-up scans were rigidly aligned to the bony anatomy and to the clinical target volume itself, mimicking two online set-up correction strategies: a conventional CBCT-guided set-up and a MR-guided set-up, respectively. Geometric coverage probability of the propagated CTVs was assessed for both set-up strategies by expanding the reference CTV with an isotropic margin varying from 0 mm to 15 mm with an increment of 1 mm. RESULTS: A margin of 10 mm could resolve the interfractional changes for 118 out of the 132 (89%) analyzed fractions when applying a bone-match registration, whereas the CTV was adequately covered in 123 (93%) fractions when the registration was directly performed at the CTV itself (soft-tissue registration). Closer analyses revealed that target coverage violation predominantly occurred for distal tumors near the junction and into the cardia. CONCLUSION: Online MR-guided soft-tissue registration protocols exhibited modest improvements of the geometric target coverage probability as compared to online CBCT-guided bone match protocols. Therefore, highly conformal target irradiation using online MR-guidance can only be achieved by implementing on-table adaptive workflows where new treatment plans are daily generated based on the anatomy of the day.

M2 Phenotype Macrophages Colocalize with Schwann Cells in Human Dental Pulp.

Macrophages are immune cells with high plasticity that perform many functions related to tissue injury and repair. They are generally categorized as 2 functional phenotypes: M1 (proinflammatory) and M2 (anti-inflammatory and prohealing). To investigate the role of macrophages in human dental pulp, we examined the localization and distributional alterations of macrophages in healthy dental pulp as well as during the reparative process of pulp capping with mineral trioxide aggregate (MTA) and in cariously inflamed pulp of adult human teeth. We also quantified the populations of M1/M2 macrophages in healthy dental pulp by flow cytometric analysis. CD68+CD86+ cells (M1 phenotype) and CD68+CD163+ cells (M2 phenotype) were 2.11% ± 0.50% and 44.99% ± 2.22%, respectively, of 2.96% ± 0.41% CD68+ cells (pan-macrophages) in whole healthy dental pulp. Interestingly, M2 phenotype macrophages were associated with Schwann cells in healthy pulp, during mineralized bridge formation, and in pulp with carious infections in vivo. Furthermore, the M2 macrophages associated with Schwann cells expressed brain-derived neurotrophic factor (BDNF) under all in vivo conditions. Moreover, we found that plasma cells expressed BDNF. Coculture of Schwann cells isolated from human dental pulp and human monocytic cell line THP-1 showed that Schwann cells induced M2 phenotypic polarization of THP-1 cell-derived macrophages. The THP-1 macrophages that maintained contact with Schwann cells were stimulated, leading to elongation of their cell shape and expression of M2 phenotype marker CD163 in cocultures. In summary, we revealed the spatiotemporal localization of macrophages and potent induction of the M2 phenotype by Schwann cells in human dental pulp. M2 macrophages protect neural elements, whereas M1 cells promote neuronal destruction. Therefore, suppressing the neurodestructive M1 phenotype and maintaining the neuroprotective M2 phenotype of macrophages by Schwann cells may be critical for development of effective treatment strategies to maintain the viability of highly innervated dental pulp.

Evaluation of Papillomacular Nerve Fiber Bundle Thickness in Glaucoma Patients with Visual Acuity Disturbance.

PURPOSE: Assessing the papillomacular nerve fiber bundle (PMB) can identify glaucoma patients with decreased visual acuity. In this study, we explore efficient methods for evaluating PMB thickness in glaucoma patients, based on swept source-optical coherence tomography (SS-OCT). METHODS: This study included 347 eyes of 205 open-angle glaucoma (OAG) patients. Patients were excluded if they had best-corrected decimal visual acuity < 0.3, axial length >28 mm, non-glaucoma ocular disease, or systemic disease affecting the visual field. We obtained vertical 12.0 × 9.0 mm 3D volume scans covering both the macular and optic disc regions with SS-OCT (DRI OCT Triton, Topcon), and measured the thickness of the PMB, as well as average macular retinal nerve fiber layer thickness (mRNFLT) and macular ganglion cell complex thickness (mGCCT) in the macular map and temporal-quadrant circumpapillary RNFL thickness (tcpRNFLT). We also measured central-strip RNFLT (csRNFLT) and GCC (csGCCT) in a 1.5 × 6.6 mm area of the scan centered between the fovea and optic nerve head. CsRNFLT and csGCCT were divided lengthwise into three 1.5 × 2.2 mm sections. We then calculated Spearman's rank correlation coefficient between these OCT measurements and visual acuity. Logistic regression analysis was used to find the cutoff value for the OCT measurements to predict logMAR < 0. RESULTS: The correlation coefficients with logMAR were 0.38 for mRNFLT, 0.44 for mGCCT, 0.37 for middle csRNFLT, 0.50 for middle csGCCT, and 0.33 for tcpRNFLT (all P < .0001). For middle csGCCT, the area under the curve indicating decreased visual acuity was 0.80, with a cutoff value of 88.6 µm (P < .001). CONCLUSIONS: We found strong associations between OCT parameters in the PMB, especially middle csGCCT, and visual acuity in patients with OAG. The thickness of the PMB may therefore be valuable information for glaucoma care and may help prevent visual acuity disturbance.