Formation and evolution of carbonaceous asteroid Ryugu: Direct evidence from returned samples

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

Pebbles and sand on asteroid (162173) Ryugu: In situ observation and particles returned to Earth

The Hayabusa2 spacecraft investigated the C-type (carbonaceous) asteroid (162173) Ryugu. The mission performed two landing operations to collect samples of surface and subsurface material, the latter exposed by an artificial impact. We present images of the second touchdown site, finding that ejecta from the impact crater was present at the sample location. Surface pebbles at both landing sites show morphological variations ranging from rugged to smooth, similar to Ryugu's boulders, and shapes from quasi-spherical to flattened. The samples were returned to Earth on 6 December 2020. We describe the morphology of >5 grams of returned pebbles and sand. Their diverse color, shape, and structure are consistent with the observed materials of Ryugu; we conclude that they are a representative sample of the asteroid.

Changes of synovial fluid biomarker levels after opening wedge high tibial osteotomy in patients with knee osteoarthritis

OBJECTIVE

The purpose of this study was to evaluate the effects of high tibial osteotomy (HTO) on the biological status of knee osteoarthritis (OA) using joint markers in synovial fluid (SF).

METHODS

Fifty patients with medial compartmental OA of the knee who underwent opening wedge HTO were enrolled. Paired SF samples from the affected knee and arthroscopic evaluation of articular cartilage were collected at the time of HTO surgery and the time of plate removal (postoperative 17 ± 4 months). The concentrations of the following SF biomarkers were measured: interleukin (IL)-1β, IL-6, IL-8, IL-10, tumour necrosis factor-α, matrix metalloproteinase (MMP)-2, MMP-3, MMP-9, MMP-13, vascular endothelial growth factor (VEGF), and cartilage oligomeric matrix protein (COMP). The Knee Society Score (KSS) and hip-knee-ankle (HKA) angle were assessed before and 2 years after HTO.

RESULTS

The KSS knee and function scores were significantly improved after HTO (mean changes of 36.4 and 23.7, respectively). The mean HKA angle was altered from mechanical varus (-8.6°) to valgus (5.2°). Concentrations of IL-6, IL-8, MMP-2, MMP-3, MMP-13, VEGF, and COMP in SF were significantly decreased after HTO (mean changes of -49.1%, -30.2%, -31.1%, -26.3%, -30.8%, -42.5%, and -13.7% from preoperative baseline, respectively). The cartilage status was improved in 19 cases (38%) after HTO. However, changes of all biomarkers were not significantly different between subjects with and without an improved cartilage status.

CONCLUSIONS

SF levels of biochemical markers for cartilage degradation and synovial inflammation were altered after HTO, suggesting an improvement in the OA disease state.

Perirenal fat thickness as a predictor of postoperative complications after laparoscopic distal gastrectomy for gastric cancer

Background

Laparoscopic distal gastrectomy is used widely in surgery for gastric cancer. Excess visceral fat can limit the ability to dissect the suprapancreatic region, potentially increasing the risk of local complications, particularly pancreatic fistula. This study evaluated perirenal fat thickness as a surrogate for visceral fat to see whether this was related to complications after laparoscopic distal gastrectomy.

Methods

Perirenal fat thickness was measured dorsal to the left kidney as an indicator of visceral fat in patients with gastric cancer who underwent laparoscopic distal gastrectomy. Patients were divided into two groups: those with and those without complications. The relationship between perirenal fat thickness and postoperative complications was evaluated.

Results

The optimal cut‐off value for predicting morbidity using adipose tissue thickness was 10·7 mm; a distance equal to or greater than this was considered a positive perirenal fat thickness sign (PTS). A positive PTS showed a significant correlation with visceral fat area. Multivariable analysis found that a positive PTS was an independent risk factor for complications (hazard ratio 4·42, 95 per cent c.i. 2·31 to 8·86; P < 0·001).

Conclusion

Perirenal fat thickness as an indicator of visceral fat was an independent predictor of postoperative complications after laparoscopic distal gastrectomy for gastric cancer.

Control system for the new RIKEN 28-GHz superconducting electron cyclotron resonance ion source for SRILAC

A new RIKEN 28-GHz superconducting electron cyclotron resonance ion source (SC-ECRIS) has been installed for the superconducting RIKEN linear accelerator (SRILAC). The new SC-ECRIS control system mainly consists of programmable logic controllers (PLCs) embedded with the Experimental Physics and Industrial Control System. To improve the reliability as compared with previous control systems, two types of PLC central processing units, sequential and Linux, have been installed in the same unit. Past experience has shown that new types of designs that can rapidly respond to system scalability are key. By connecting PLC stations using star-topology field buses, their rapid and cost-effective response to system changes is realized for the new devices. Furthermore, a unique data acquisition system employing a 920-MHz-band radio was developed to measure analog data such as the temperature at the high-voltage stage.

High intensity vanadium beam for synthesis of new superheavy elements with well-controlled emittance by using "slit triplet"

To provide a very powerful vanadium (V) beam with an intensity of at least 6 particle μA for synthesizing a new superheavy element (SHE) with atomic number Z = 119, we have developed a high-temperature oven (HTO) system to evaporate the metallic V powder inside the new superconducting (SC) electron cyclotron ion source. We successfully extracted a V¹³⁺ beam with a maximum beam intensity of 600 eμA with 2.8-kW microwave power and 900-W heating power of the HTO. Furthermore, from a systematic study of the dependence of the beam intensity on the microwave power and the HTO power, we successfully produced a V¹³⁺ beam of 300 eμA at a consumption rate of 3 mg/h, allowing a one-month duration continuous beam to carry out the SHE synthesis. In addition, to avoid serious damage to newly introduced SC acceleration cavities by beam losses, the beam should be transported with a well-controlled emittance. To efficiently limit the beam emittance, we employed a slit triplet consisting of three pairs of slits installed around the focus point of the low-energy beam transport. The first result of the emittance reduction was observed by a pepper-pot type emittance meter as a function of the acceptance of the slit triplet.

Comparison of mediastinal lymph node metastases from adenocarcinoma of the esophagogastric junction versus lower esophageal squamous cell carcinoma with involvement of the esophagogastric junction

The distribution of mediastinal lymph node metastasis in patients with adenocarcinoma of the esophagogastric junction (AEG) remains unclear. Additionally, the distribution of nodal mediastinal metastasis from squamous cell carcinoma (SCC) of the lower esophagus with involvement of the esophagogastric junction remains unclear, given the very limited number of these patients. In this retrospective review, we compared the outcomes of radical lymphadenectomy of the mediastinum, including upper mediastinal lymphadenectomy, between patients with AEG and those with SCC. From 2005 to 2017, 69 consecutive patients underwent esophagectomy via right thoracotomy or minimally invasive esophagectomy for a Siewert type I or II tumor with esophageal invasion ≥3 cm. We analyzed the incidences of mediastinal lymph node metastasis in this group relative to those of 73 patients with SCC with involvement of the esophagogastric junction who consecutively underwent esophagectomy during the same period. Mediastinal lymph node metastasis was seen in 26 of 69 patients with AEG (38%), with upper, middle, lower mediastinal nodal metastasis instances of 20%, 17%, and 23%, respectively. Mediastinal lymph node metastasis was seen in 23 of 73 patients with SCC (32%), with upper, middle, lower mediastinal nodal metastasis instances of 12%, 16%, and 19%, respectively. This mediastinal lymph nodal metastasis distribution did not statistically differ between patients with AEG and those with SCC. The relapse-free survival outcomes were poor for patients with clinical (P < 0.01) or pathological (P < 0.01) nodal metastasis of the mediastinum with AEG. In contrast, patients with clinical or pathological mediastinal nodal metastases of SCC did not have extremely poor survival outcomes, compared to patients with AEG. Despite the limited dataset available for analysis, patients with AEG and those with SCC might exhibit similar incidences and distribution of mediastinal lymph node metastasis. However, the clinical or pathological metastasis of AEG to the mediastinum was associated with poor survival outcomes, even if radical mediastinal lymphadenectomy including the upper mediastinal lymphadenectomy was performed.

Laparoscopic proximal gastrectomy with double-flap technique versus laparoscopic subtotal gastrectomy for proximal early gastric cancer

Background

Laparoscopic proximal gastrectomy with double‐flap technique (LPG‐DFT) and laparoscopic subtotal gastrectomy (LSTG) may replace laparoscopic total gastrectomy (LTG) for proximal early gastric cancer. The aim of this study was to evaluate short‐ and long‐term outcomes after LPG‐DFT and LSTG.

Methods

Patients who underwent LPG‐DFT or LSTG at the Cancer Institute Hospital in Tokyo between January 2006 and April 2015 were included in this retrospective study. Operative procedures were selected based on the distance from the cardia to the proximal boundary of the tumour, tumour location and predicted remnant stomach volume. Patient characteristics, surgical data, markers of postoperative nutritional status, such as blood chemistry and bodyweight loss, and endoscopic findings were compared between procedures. The main study outcome was nutritional status.

Results

A total of 161 patients (LPG‐DFT 51, LSTG 110) were included. Types of postoperative complication occurring more than 30 days after surgery differed between the two procedures. Remnant stomach ulcers, including anastomotic ulcers, were observed only after LPG‐DFT, whereas complications involving the small intestine, such as internal hernia or small bowel obstruction, occurred more frequently after LSTG. Values for total protein, albumin, prealbumin and bodyweight loss were comparable between the two procedures at 36 months after surgery. Haemoglobin concentrations were higher after LPG‐DFT than after LSTG at 24 months (13·4 versus 12·8 g/dl respectively; P = 0·045) and 36 months (13·5 versus 12·8 g/dl; P = 0·007) after surgery. The rate of Los Angeles grade B or more severe reflux oesophagitis was comparable.

Conclusion

LPG‐DFT and LSTG for proximal early gastric cancer have similar outcomes, but different types of complication.

92Transcatheter aortic valve implantation improves cerebral blood flow and cognitive function in elderly patients with aortic stenosis - Brain perfusion SPECT imaging study

Background

Cognitive impairment and depression are commonly noted in elderly frail patients with severe aortic stenosis (AS). However, their mechanisms and reversibility after treatment remain remain to be examined.

Purpose

In this study, we examined whether transcatheter aortic valve implantation (TAVI) increases cerebral blood flow (CBF) in cognitive/emotional brain areas, such as the hippocampus, in the elderly patients with severe AS.

Methods

We examined consecutive 15 right-handed patients with severe AS who were eligible for TAVI (median age 83.2 years, 12 (80%) women). We evaluated the following assessments both at baseline and 3 months after TAVI. Frailty was evaluated based on Fried scale, which consists of 5 items, including gait speed, cognitive function, weight loss, exhaustion, and inactivity. Frail and pre-frail were defined as greater than 3 and 1∼2 in the scale, respectively. Cognitive and emotional status were evaluated with Logical Memory (LM) II, Mini Mental State Examination (MMSE), and geriatric depression scale (GDS). Lower LM II (less than 4 points) and MMSE (less than 24 points) and higher GDS (more than 6 points) indicate worse memory, general cognitive function, and depressive symptoms, respectively. CBF images were recorded with 99mTc single-photon emission computed tomography and were analyzed using SPM12. Briefly, CBF images were firstly normalized to the standard Montreal Neurological Institute space. Then, a voxel-wise parametric analysis was conducted between normalized CBF images at baseline and those after TAVI (P<0.005 at each voxel). Continuous variables were presented as mean ± standard error (SE). Normality was assessed using the Shapiro-Wilk test. Continuous variables were compared with the use of paired t test. Linear mixed-model analysis was performed to evaluate changes in neuropsychological tests and CBF over time.

Results

In the present study, all patients were not robust but pre-frail (47.3%) or frail (53.7%). LM II score was significantly improved at 3 months after TAVI compared with baseline (baseline, 8.7 vs. 3 months, 13.8, P<0.01) (Figure A), whereas no significant changes in MMSE or GDS scores were noted (baseline, 24.6 vs. 3 months, 25.2 for MMSE; baseline, 4.3 vs. 3 months, 4.2 for GDS). Importantly, although no patients showed clinical symptoms or signs for transient ischemic attack or stroke after TAVI, CBF in the local regions, including the right hippocampus, was significantly increased after TAVI compared with baseline (P<0.005 at each voxel) (green arrowheads) (Figure B). Furthermore, CBF in the right hippocampus were positively correlated with LM II scores (P=0.017) (Figure C).

Figure 1

Conclusions

These results provide the first evidence that TAVI improves cerebral perfusion (especially that in the hippocampus) and cognitive functions in elderly patients with severe AS.

Photoluminescence in hexagonal silicon carbide by direct femtosecond laser writing

Direct femtosecond laser writing has been used to produce localized regions of photo-luminescent emission in 4H- and 6H-silicon carbide (SiC). Arrays of active color centers were fabricated by different pulse laser energies in the sites of square grids at various depths (from surface level to 10 μm below surface). We optically characterized the fabricated color centers using confocal imaging with 532 and 780 nm excitation, photo-luminescence spectroscopy, and lifetime decay at room temperature. We show that the technique can produce specifically the silicon vacancy color center emitting in the range 850-950 nm and other emitters in the 700 nm. This method can be adopted to engineer color centers in (SiC) at different depths in the material for single-photon generation, sensing, display fabrication, and light emitting diodes.

[A Case of Retro-Odontoid Pseudotumor in a Very Elderly Individual]

Retro-odontoid pseudotumors are mainly caused by aging or rheumatoid arthritis. We treated a very elderly patient with retro-odontoid pseudotumor. A 92-year-old man was admitted with the chief complaints of difficulty walking and progressive numbness in the right upper and lower extremities. Neurological examination revealed muscle weakness and exaggerated tendon reflexes of the right upper and lower extremities, and disturbance in skilled motor activities of the fingers, bilaterally. He had no bladder or rectal disturbances. The Japanese Orthopaedic Association(JOA)score for cervical myelopathy was 10/17. Rheumatoid arthritis was interpreted as negative. Radiography of the neck showed no atlanto-axial instability. Cervical magnetic resonance(MR)imaging revealed a mass located posterior to the C2 odontoid process, severely compressing the cervical cord. The patient underwent a C1 laminectomy and C2 half laminectomy without fixation to achieve cord decompression. Postoperatively, muscle weakness in the right upper and lower extremities was remarkably improved, and gait disturbance was also improved. However, skilled motor activities of the fingers on the right hand during tasks such as writing letters, holding a cup, and using chopsticks, were not improved. JOA score was improved to 14/17. Postoperative radiography revealed no atlanto-axial instability and MR imaging revealed adequate decompression of the spinal canal. Laminectomy without fixation is recommended as an effective and less invasive treatment for retro-odontoid pseudotumor, especially in very elderly patients without atlanto-axial instability.

Oesophagectomy with or without supraclavicular lymphadenectomy after neoadjuvant treatment for squamous cell carcinoma of the oesophagus

Background

Treatment of supraclavicular nodes remains controversial among patients with oesophageal squamous cell carcinoma. This study assessed the outcomes of patients who underwent oesophagectomy with or without supraclavicular lymphadenectomy after neoadjuvant treatment.

Methods

This was a single-centre retrospective cohort study. Patients with oesophageal squamous cell carcinoma and clinically negative supraclavicular nodes who underwent oesophagectomy after neoadjuvant treatment between January 2005 and December 2015 were included. Overall and relapse-free survival were compared between patients who did or did not undergo supraclavicular nodal dissection. Propensity score matching was used to correct for differences in prognostic factors between the groups.

Results

Some 223 patients underwent supraclavicular lymphadenectomy. The prevalence of pathologically confirmed supraclavicular metastasis was 10·3 per cent, and these patients had poor 5-year relapse-free (7 per cent) and overall (14 per cent) survival. Only two of 55 patients who did not undergo supraclavicular lymphadenectomy had recurrent disease in the supraclavicular region without distant metastasis. There was no statistically significant difference between the groups in relapse-free survival (hazard ratio (HR) 0·95, 95 per cent c.i. 0·61 to 1·47; P = 0·821) or overall survival (HR 0·86, 0·52 to 1·40; P = 0·544). Similarly, no significant difference in relapse-free or overall survival was observed between the propensity score-matched groups.

Conclusion

For patients with clinically negative supraclavicular lymph nodes, prophylactic supraclavicular lymphadenectomy may be omitted when neoadjuvant treatment is administered.

Effects of once-monthly minodronate versus risedronate in osteoporosis patients with rheumatoid arthritis: a 12-month randomized head-to-head comparison

A head-to-head comparison of once-monthly oral bisphosphonates minodronate (MIN) and risedronate (RIS) in patients with rheumatoid arthritis (RA) demonstrated that MIN has the same effect as RIS on increase in bone mineral density (BMD) and a stronger effect on inhibition of bone resorption than RIS, suggesting that MIN is a promising treatment option for osteoporosis patients with RA.

INTRODUCTION

To evaluate the effect of once-monthly oral MIN in patients with RA, a prospective, randomized, open-label, head-to-head comparison with once-monthly oral RIS was conducted.

METHODS

A total of 83 patients with RA were randomly assigned to either once-monthly oral MIN 50 mg (n = 42) or once-monthly oral RIS 75 mg (n = 41). Serial BMD and bone turnover markers were measured and compared between the treatment groups.

RESULTS

BMD (lumbar spine, total hip, femoral neck) increased significantly after 12 months of treatment with MIN (3.8, 2.0, and 2.2%, respectively, P < 0.05) and RIS (3.6, 1.9, and 1.9%, respectively, P < 0.05). There were no significant differences between the treatment groups. Percent changes of bone turnover markers from baseline to 12 months in the MIN group were significantly greater than those in the RIS group (TRACP-5b: - 36.3 vs - 19.3%, P < 0.05; NTX: - 27.1 vs - 17.3%, P < 0.05; BAP: -30.2 vs -19.4%, P < 0.05).

CONCLUSIONS

The present study of RA patients demonstrated that MIN has the same effect as RIS on increase in BMD and a stronger effect on inhibition of bone resorption than RIS. The results suggest that MIN is a promising treatment option for osteoporosis patients with RA.

Measured moisture in buildings and adverse health effects: A review

It has not yet been possible to quantify dose-related health risks attributable to indoor dampness or mold (D/M), to support setting specific health-related limits for D/M. An overlooked target for assessing D/M is moisture in building materials, the critical factor allowing microbial growth. A search for studies of quantified building moisture and occupant health effects identified 3 eligible studies. Two studies assessed associations between measured wall moisture content and respiratory health in the UK. Both reported dose-related increases in asthma exacerbation with higher measured moisture, with 1 study reporting an adjusted odds ratio of 7.0 for night-time asthma symptoms with higher bedroom moisture. The third study assessed relationships between infrared camera-determined wall moisture and atopic dermatitis in South Korea, reporting an adjusted odds ratio of 14.5 for water-damaged homes and moderate or severe atopic dermatitis. Measuring building moisture has, despite extremely limited available findings, potential promise for detecting unhealthy D/M in homes and merits more research attention. Further research to validate these findings should include measured "water activity," which directly assesses moisture availability for microbial growth. Ultimately, evidence-based, health-related thresholds for building moisture, across specific materials and measurement devices, could better guide assessment and remediation of D/M in buildings.

Ultrafine, fine, and black carbon particle concentrations in California child-care facilities

Although many U.S. children spend time in child care, little information exists on exposures to airborne particulate matter (PM) in this environment, even though PM may be associated with asthma and other respiratory illness, which is a key concern for young children. To address this data gap, we measured ultrafine particles (UFP), PM_2.5 , PM₁₀ , and black carbon in 40 California child-care facilities and examined associations with potential determinants. We also tested a low-cost optical particle measuring device (Dylos monitor). Median (interquartile range) concentrations for indoor UFP, gravimetric PM_2.5 , real-time PM_2.5 , gravimetric PM₁₀ , and black carbon over the course of a child-care day were 14 000 (11 000-29 000) particles/cm³ , 15 (9.6-21) μg/m³ , 15 (11-23) μg/m³ , 48 (33-73) μg/m³ , and 0.43 (0.25-0.65) ng/m³ , respectively. Indoor black carbon concentrations were inversely associated with air exchange rate (Spearman's rho = -.36) and positively associated with the sum of all Gaussian-adjusted traffic volume within a one-kilometer radius (Spearman's rho = .45) (P-values <.05). Finally, the Dylos may be a valid low-cost alternative to monitor PM levels indoors in future studies. Overall, results indicate the need for additional studies examining particle levels, potential health risks, and mitigation strategies in child-care facilities.

Development of a method to relate the moisture content of a building material to its water activity

Subjective indicators of building dampness consistently have been linked to health, but they are, at best, semi-quantitative, and objective and quantitative assessments of dampness are also needed to study dampness-related health effects. Investigators can readily and non-destructively measure the "moisture content" (MC) of building materials with hand-held moisture meters. However, MC does not indicate the amount of the water in a material that is available to microorganisms for growth, that is, the "water activity" (A_w ). Unfortunately, A_w has not been readily measurable in the field and is not relatable to MC unless previously determined experimentally, because for the same moisture meter reading, A_w can differ across materials as well as during moisture adsorption vs desorption. To determine the A_w s that correspond to MC levels, stable air relative humidities were generated in a glove box above saturated, aqueous salt solutions, and the A_w of gypsum board and the relative humidity of the chamber air were tracked until they reached equilibrium. Strong correlations were observed between meter readings and gravimetrically determined MC (r=.91-1.00), among readings with three moisture meters (r=.87-.98), and between meter readings and gypsum board A_w (r=.77-.99).

Observation-based metrics for residential dampness and mold with dose-response relationships to health: A review

An important proportion of respiratory illness is considered attributable to residential dampness or mold (D/M). Developing health-protective D/M guidelines has been challenging, in part because unhealthy levels of indoor D/M cannot be defined using available microbiological measurements. This review paper explores reported multilevel, observation-based (eg visual or olfactory) D/M metrics for potential in defining unhealthy levels of residential D/M. For many of the 33 multilevel residential D/M metrics identified, health risks generally increased as observed D/M increased. Although some metrics seemed too complex for practical use, simple metrics had among the strongest associations with health outcomes. Available findings suggest the feasibility of setting observation-based D/M thresholds to trigger remedial action, using further improved D/M metrics without microbiological measurements (at least until the actual dampness-related agents that cause illness are better quantified). Additional data would allow setting health-protective D/M thresholds more precisely. Also, metrics could better reflect hidden D/M by more strongly emphasizing mold odor, which has demonstrated strong associations with health effects.

Influence of coronal bowing on the lower alignment and the positioning of component in navigation and conventional total knee arthroplasty

BACKGROUND

Coronal alignment is an important factor for the function and longevity of total knee arthroplasty (TKA). Coronal bowing of the lower extremity is common among Asians and it may pose a risk for malalignment of the lower leg and malposition of component.

HYPOTHESIS

We hypothesized that coronal bowing itself has a risk for malalignment of the lower leg and malposition of femoral/tibial components and that navigation TKA is beneficial for patients with coronal bowing. We investigated the incidence of femoral/tibial bowing in patients treated with TKA and compared the radiographic parameters between the navigation group and the conventional group. Additionally, the influence of coronal bowing on these radiographic parameters was investigated.

MATERIALS AND METHODS

We enrolled 35 patients with knee osteoarthritis and 70 bilateral simultaneous TKAs. The patients underwent TKA with the use of a computer tomography-free navigation in one knee and conventional TKA in the contralateral knee. Preoperative coronal bowing were measured, and the subjects were divided into 2 subgroups, i.e. the bowing group and the non-bowing group. Lateral bowing was expressed as plus (+) and medial bowing was expressed as minus (-). Various radiographic parameters, including coronal bowing, lower leg alignment, component position, and outliers were compared between the navigation group and the conventional group.

RESULTS

Femoral bowing varied from -7.4° to 10.9° with an average of 3.0°. Tibial bowing varied from -4.1° to 4.6° with an average of 0.4°. The femoral component was placed more properly in the navigation group. Number of outlier regarding to the coronal femoral component angle to the femoral mechanical axis was 14 cases (37.8%) in the bowing group and 6 cases (18.2%) in the non-bowing group (P=0.04).

DISCUSSION

In conclusion, coronal femoral bowing has an important effect on femoral bone cut in TKA. The navigated TKA was more consistent than conventional TKA in aiding proper alignments of femoral component.

LEVEL OF EVIDENCE

Level II, comparative prospective study.

Higher measured moisture in California homes with qualitative evidence of dampness

Relationships between measured moisture and qualitative dampness indicators (mold odor, visible mold, visible water damage, or peeling paint) were evaluated using data collected from California homes in a prospective birth cohort study when the infants were 6 or 12 months of age (737 home visits). For repeated visits, agreement between observation of the presence/absence of each qualitative indicator at both visits was high (71-87%, P < 0.0001). Among individual indicators, musty odor and visible mold were most strongly correlated with elevated moisture readings. Measured moisture differed significantly between repeated visits in opposite seasons (P < 0.0001), and dampness increased with the number of indicators in a home. Linear mixed-effect models showed that 10-unit increases in maximum measured moisture were associated with the presence of 0.5 additional dampness indicators (P < 0.001). Bedroom (BR) walls were damper than living room (LR) walls in the same homes (P < 0.0001), although both average and maximum readings were positively correlated across room type (r = 0.75 and 0.67, respectively, both P < 0.0001). Exterior walls were significantly damper than interior walls (P < 0.0001 in both LRs and BRs), but no differences were observed between maximum wall readings and measurements at either window corners or sites of suspected dampness.

Usefulness of long tibial axis to measure medial tibial slope for opening wedge high tibial osteotomy

PURPOSE

To assess which tibial slope measurements on knee, whole leg radiographs and three-dimensional reconstructed computed tomography (CT) were useful in clinical practice before and after opening wedge high tibial osteotomy.

METHODS

Medial and lateral tibial slopes on knee, whole leg radiographs and three-dimensional reconstructed CT were measured in 50 patients with knee osteoarthritis. To investigate the intraobserver reproducibility and interobserver reliability for each medial and lateral tibial slope on knee, whole leg radiographs and CT, the measurements were repeated twice by two observers. The statistical differences between the medial and lateral tibial slopes obtained by the three methods, and the differences and correlation coefficients for the medial and lateral tibial slopes between knee or whole leg radiographs and CT were calculated.

RESULTS

The reproducibility and reliability of medial and lateral tibial slopes on CT were superior to those on whole leg or knee radiographs. The medial and lateral tibial slopes on whole leg radiographs had better reproducibility and reliability than those on knee radiographs. The mean medial tibial slopes on knee, whole leg radiographs and CT were 9.3 ± 3.4°, 12.3 ± 4.3° and 11.0 ± 3.9°, respectively. The mean lateral tibial slopes were 7.9 ± 3.1°, 9.6 ± 3.6° and 9.3 ± 2.9°, respectively. The medial tibial slopes on knee, whole leg radiographs and CT were significantly higher than the lateral tibial slopes (p < 0.01 for all).

CONCLUSIONS

Tibial slope measurements using CT required time and specialized software. Therefore, measurements of the medial tibial slope using the long tibial axis on whole leg radiographs were more reproducible and reliable and could be an alternative to CT in clinical practice.

LEVEL OF EVIDENCE

III.

Activation of a chondrocyte volume-sensitive Cl(-) conductance prior to macroscopic cartilage lesion formation in the rabbit knee anterior cruciate ligament transection osteoarthritis model

OBJECTIVE

The anterior cruciate ligament transection (ACLT) rabbit osteoarthritis (OA) model confers permanent knee instability and induces joint degeneration. The degeneration process is complex, but includes chondrocyte apoptosis and OA-like loss of cartilage integrity. Previously, we reported that activation of a volume-sensitive Cl(-) current (ICl,vol) can mediate cell shrinkage and apoptosis in rabbit articular chondrocytes. Our objective was therefore to investigate whether ICl,vol was activated in the early stages of the rabbit ACLT OA model.

DESIGN

Adult Rabbits underwent unilateral ACLT and contralateral arthrotomy (sham) surgery. Rabbits were euthanized at 2 or 4 weeks. Samples were analyzed histologically and with assays of cell volume, apoptosis and electrophysiological characterization of ICl,vol.

RESULTS

At 2 and 4 weeks post ACLT cartilage appeared histologically normal, nevertheless cell swelling and caspase 3/7 activity were both significantly increased compared to sham controls. In cell-volume experiments, exposure of chondrocytes to hypotonic solution led to a greater increase in cell size in ACLT compared to controls. Caspase-3/7 activity, an indicator of apoptosis, was elevated in both ACLT 2wk and 4wk. Whole-cell currents were recorded with patch clamp of chondrocytes in iso-osmotic and hypo-osmotic external solutions under conditions where Na(+), K(+) and Ca(2+) currents were minimized. ACLT treatment resulted in a large increase in hypotonic-activated chloride conductance.

CONCLUSION

Changes in chondrocyte ion channels take place prior to the onset of apparent cartilage loss in the ACLT rabbit model of OA. Further studies are needed to investigate if pharmacological inhibition of ICl,vol decreases progression of OA in animal models.

Systematic review and meta-analysis on the significance of salvage esophagectomy for persistent or recurrent esophageal squamous cell carcinoma after definitive chemoradiotherapy

The therapeutic strategy to be recommended in case of recurrent or persistent squamous cell esophageal cancer after completed definitive chemoradiotherapy (dCRT) has to be documented. Salvage esophagectomy has traditionally been recognized as a viable option, but many clinicians oppose the use of surgery due to the associated excessive morbidity and mortality. 'Second-line' chemoradiotherapy (CRT) without surgery may offer a treatment alternative in these difficult and demanding clinical situations. Until now, no comprehensive attempt has been carried out to compare the respective therapeutic options. A systematic literature search was performed focusing on studies comparing survival and treatment-related mortality in patients submitted to salvage esophagectomy or second-line CRT for recurrent or persistent esophageal squamous cell carcinoma after dCRT. Hazard ratios and risk ratios were calculated to compare the effect of these therapeutic strategies on overall survival and treatment-related mortality, respectively. Four studies containing 219 patients, with persistent or recurrent esophageal squamous cell carcinoma after dCRT, were included in the meta-analysis. The analysis revealed an overall survival benefit following salvage esophagectomy with a pooled hazard ratio for death of 0.42 (95% confidence interval 0.21-0.86, P = 0.017) compared with second-line CRT. A treatment-related mortality of 10.3% was recorded in the 36 patients who were submitted to salvage esophagectomy, while it was impossible to perform a meta-analysis comparing treatment-related mortality between the groups. Salvage esophagectomy offers significant gain in long-term survival compared with second-line CRT, although the surgery is potentially at a price of a high treatment-related mortality.

Role of Prealbumin as a Powerful and Simple Index for Predicting Postoperative Complications After Gastric Cancer Surgery

BACKGROUND

Preoperative factors, including nutritional status, may have strong correlations with postoperative morbidities. The current study evaluated preoperative prealbumin concentrations as a predictor of postoperative complications after gastric surgery.

METHODS

A retrospective study of 1798 patients who underwent gastrectomy for gastric adenocarcinoma was performed. Information was collected on basic patient characteristics, preoperative laboratory findings, and 30 day postoperative complications. The patients were divided into three groups based on prealbumin concentrations (≥22 mg/dL, <22 to ≥15 mg/dL, and <15 mg/dL) for analysis.

RESULTS

The overall complication rate was 21.7 %, and the infection rate was 16 %. Subgroup analysis based on prealbumin concentrations showed that complication rates were markedly elevated with decreasing concentrations of prealbumin. Multivariate analysis using a logistic regression model showed that both overall and infectious complications were strongly associated with male gender, elevated C-reactive protein (CRP), and decreased prealbumin levels (p < 0.05). Even in patients with a CRP level higher than 0.1 mg/dL, male gender and low prealbumin concentrations (<15 mg/dL) were significantly correlated with overall and infectious morbidities (p < 0.05).

CONCLUSIONS

Preoperative prealbumin concentrations are useful predictors of short-term postoperative outcomes after gastrectomy.

Relief of dysphagia during neoadjuvant treatment for cancer of the esophagus or gastroesophageal junction

Dysphagia is the main symptom of cancer of the esophagus and gastroesophageal junction and causing nutritional problems and weight loss, often counteracted by insertion of self-expandable metal stents or nutrition via an enteral route. Clinical observations indicate that neoadjuvant therapy may effectively and promptly alleviate dysphagia, making such nutrition supportive interventions redundant before surgical resection. The objective of the current study was to carefully study the effects of induction neoadjuvant therapy on dysphagia and its subsequent course and thereby investigate the actual need for alimentary gateways for nutritional support. Thirty-five consecutive patients scheduled for neoadjuvant therapy were recruited and assessed regarding dysphagia and appetite at baseline, after the first cycle of preoperative treatment with either chemotherapy alone or with chemoradiotherapy and before surgery. Platinum-based therapy in combination with 5-fluorouracil was administered intravenously days 1-5 every 3 weeks and consisted of three treatments. Patients receiving combined chemoradiotherapy started radiotherapy on day one of second chemotherapy cycle. They received fractions of 2 Gy/day each up to a total dose of 40 Gy. Watson and Ogilvie dysphagia scores were used to assess dysphagia, while appetite was assessed by the Edmonton Assessment System Visual analogue scale-appetite questionnaire. Patients were evaluated at regular outpatient clinic visits or by telephone. The histological tumor response in the surgical specimen was assessed using the Chirieac scale. Ten patients scheduled for neoadjuvant chemotherapy and 25 patients scheduled for chemoradiotherapy were included in the analysis. There was a significant improvement in dysphagia in both treatment groups, according to both scales, already from baseline to the completion of the first chemotherapy cycle which remained to the end of the neoadjuvant treatment (P < 0.001). Appetite also improved after the first chemotherapy cycle (P = 0.03). Body weight did not change during any type of neoadjuvant therapy. We were unable to demonstrate any association between relief of dysphagia and the degree of histological response to neoadjuvant therapy in the surgical specimen. The present study shows that a platin - 5FU-based neoadjuvant chemotherapy, with or without concomitant radiotherapy, effectively and promptly relieves dysphagia in patients presenting with cancers of the esophagus or gastroesophageal junction already after the first cycle.

Identification of c-Jun as bcl-2 Transcription Factor in Human Uterine Endometrium

We describe the application of the biomolecular interaction (BIA) technique to detection of the interaction between protein (e.g., c-Jun) and DNA (e.g., two AP-1 motifs from bcl-2 promoter), compared with immunohistochemistry (IHC) of c-Jun. The specific binding assay for the interaction of c-Jun and activating protein-1 (AP-1) motifs was performed using a Biacore 2000 system. Intense immunoreactivity of c-Jun in glandular cells of the human uterine endometrium was observed in the proliferative phase, while c-Jun in stromal cells was expressed throughout the menstrual cycle. In contrast to the IHC of c-Jun, the specific binding of c-Jun to two separate AP-1 motifs in the bcl-2 promoter region was detected only in nuclear extracts of glandular cells, but not in stromal cells, during the proliferative phase. These results indicate that, while transmitting various signals, c-Jun enhances the transcription level of bcl-2, which in turn keeps glandular cells alive and proliferating in normal human endometrium during the proliferative phase. Moreover, the method involving real-time biomolecular interactions such as DNA-protein binding is novel for the study of transcription factors when combined with IHC.

Selective Killing of HIV-Infected Cells by Liposomes Composed of dimyristoylphosphatidylcholine/phosphatidylserine/cholesterol

We have previously shown that liposomes containing fragment A of diphtheria toxin, which were prepared by the detergent-dialysis method with egg phosphatidylcholine, phosphatidylserine and cholesterol, possess a selective killing activity against human immunodeficiency virus (HIV)-1-infected cells, but not against uninfected cells (Ikuta et al., 1987). Since the liposomes were found to be unstable in human plasma in vitro, we prepared improved liposomes by the extrusion method with dimyristoylphosphatidylcholine instead of egg phosphatidylcholine. These liposomes were found to be very stable in human plasma, and also possessed the selective killing activity against HIV-1-infected cells. In addition, it was found that the fragment A in the liposomes was not necessary for the selective cell killing activity. The cell killing activity and selectivity of HIV-1-infected cells of the liposomes were remarkably affected by cholesterol content and the acyl chain length of the saturated fatty acid of phosphatidylcholines. These data suggest that membranes of liposomes can interact specifically with HIV-1-infected cells, but not with uninfected cells, resulting in the inhibition of cell proliferation.

Lidocaine induces ROCK-dependent membrane blebbing and subsequent cell death in rabbit articular chondrocytes

Local anesthetics are administered intraarticularly for pain control in orthopedic clinics and surgeries. Although previous studies have shown that local anesthetics can be toxic to chondrocytes, the underlying cellular mechanisms remain unclear. The present study investigates acute cellular responses associated with lidocaine-induced toxicity to articular chondrocytes. Rabbit articular chondrocytes were exposed to lidocaine and their morphological changes were monitored with live cell microscopy. The viability of chondrocytes was evaluated using a fluorescence based LIVE/DEAD assay. Acute treatment of chondrocytes with lidocaine (3-30 mM) induced spherical protrusions on the cell surface (so called "membrane blebbing") in a time- and concentration-dependent manner. The concentration-response relationship for the lidocaine effect was shifted leftward by elevating extracellular pH, as expected for the non-ionized lidocaine being involved in the bleb formation. ROCK (Rho-kinase) inhibitors Y-27632 and fasudil completely prevented the lidocaine-induced membrane blebbing, suggesting that ROCK activation is required for bleb formation. Caspase-3 levels were unchanged by 10 mM lidocaine (p = 0.325) and a caspase inhibitor z-VAD-fmk did not affect the lidocaine-induced blebbing (p = 0.964). GTP-RhoA levels were significantly increased (p < 0.001), but Rho inhibitor-1 failed to suppress the membrane blebbing (p = 0.875). Lidocaine (30 mM) reduced the cell viability of isolated chondrocytes (p < 0.001) and in situ chondrocytes (p < 0.001). The chondrotoxicity was attenuated by pretreatment of cells with ROCK inhibitors or a myosin-II inhibitor blebbistatin (p < 0.001). These findings suggest that lidocaine induces ROCK-dependent membrane blebbing and thereby produces a cytotoxic effect on chondrocytes. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:754-762, 2016.

Discrimination between natural and other gamma ray sources from environmental gamma ray dose rate monitoring data

In this study, a method to discriminate between natural and other γ-ray sources from environmental γ-ray dose rate monitoring data was developed, and it was successfully applied to actual monitoring data around nuclear facilities. The environmental dose rate is generally monitored by NaI(Tl) detector systems in the low dose rate range. The background dose rate varies mainly as a result of the deposition of (222)Rn progeny in precipitation and shielding of the ground by snow cover. Increments in the environmental dose rate due to radionuclides released from nuclear facilities must be separated from these background variations. The method in the present study corrects for the dose rate variations from natural sources by multiple regression analysis based on the γ-ray counting rates of single-channel analysers opened in the energy ranges of γ-rays emitted by (214)Bi and (208)Tl. Assuming a normal distribution of the results and using the one-sided type I error of 0.01 while ignoring the type II error, the detection limit of the γ-ray dose rate from artificial sources was 0.77 nGy h(-1).

Improved quality of cartilage repair by bone marrow mesenchymal stem cells for treatment of an osteochondral defect in a cynomolgus macaque model

BACKGROUND AND PURPOSE

Integration of repaired cartilage with surrounding native cartilage is a major challenge for successful tissue-engineering strategies of cartilage repair. We investigated whether incorporation of mesenchymal stem cells (MSCs) into the collagen scaffold improves integration and repair of cartilage defects in a cynomolgus macaque model.

METHODS

Cynomolgus macaque bone marrow-derived MSCs were isolated and incorporated into type-I collagen gel. Full-thickness osteochondral defects (3 mm in diameter, 5 mm in depth) were created in the patellar groove of 36 knees of 18 macaques and were either left untreated (null group, n = 12), had collagen gel alone inserted (gel group, n = 12), or had collagen gel incorporating MSCs inserted (MSC group, n = 12). After 6, 12, and 24 weeks, the cartilage integration and tissue response were evaluated macroscopically and histologically (4 null, 4 gel, and 4 MSC knees at each time point).

RESULTS

The gel group showed most cartilage-rich reparative tissue covering the defect, owing to formation of excessive cartilage extruding though the insufficient subchondral bone. Despite the fact that a lower amount of new cartilage was produced, the MSC group had better-quality cartilage with regular surface, seamless integration with neighboring naïve cartilage, and reconstruction of trabecular subchondral bone.

INTERPRETATION

Even with intensive investigation, MSC-based cell therapy has not yet been established in experimental cartilage repair. Our model using cynomolgus macaques had optimized conditions, and the method using MSCs is superior to other experimental settings, allowing the possibility that the procedure might be introduced to future clinical practice.

Extracellular and intracellular mechanisms of mechanotransduction in three-dimensionally embedded rat chondrocytes

Purpose

Articular cartilage homeostasis involves modulation of chondrocyte matrix synthesis in response to mechanical stress (MS). We studied extracellular and intracellular mechanotransduction pathways mediating this response.

Methods

We first confirmed rapid up-regulation of the putative chondro-protective cytokine, interleukin (IL)-4, as an immediate response to MS. We then studied the role of IL-4 by investigating responses to exogenous IL-4 or a specific IL-4 inhibitor, combined with MS. Next we investigated the intracellular second messengers. Since chondrocyte phenotype alters according to the extracellular environment, we characterized the response to mechanotransduction in 3-dimensionally embedded chondrocytes.

Results

Expression of aggrecan and type II collagen was significantly up-regulated by exogenous IL-4 whereas MS-induced matrix synthesis was inhibited by an IL-4 blocker. Further, MS-induced matrix synthesis was completely blocked by a p38 MAPK inhibitor, while it was only partially blocked by inhibitors of other putative second messengers.

Conclusion

IL-4 mediates an extracellular pathway of mechanotransduction, perhaps via an autocrine/paracrine loop, while p38 mediates an intracellular pathway prevalent only in a 3-dimensional environment.