INFLUENCE OF STATIC ELECTRICITY ON RADON MEASUREMENT USING PASSIVE DETECTORS

In order to investigate the influence of the static electricity on the measurement using passive radon detector, detectors were charged at the surface of chamber and its CR-39 elements respectively on purpose before the exposure in this study. The results of in-chamber experiments revealed that the static electricity would lead to critical influence on measurement especially when the CR-39 elements were negatively charged. The static charge would remain for several ten hours, which result in more significant influence on the short-term measurement.

Restoring T-helper 17 cell/regulatory T-cell balance and decreasing disease activity by rapamycin and all-trans retinoic acid in patients with systemic lupus erythematosus

OBJECTIVE

This study aimed to investigate the effect of rapamycin (RAPA) alone or in combination with all-trans retinoic acid (ATRA) on the T-helper 17 (Th17) cell/regulatory T-cell (Treg) balance in patients with systemic lupus erythematosus (SLE) and to evaluate the clinical efficacy.

METHODS

Seventy patients with SLE were enrolled. They were randomly and equally divided into RAPA and RAPA + ATRA groups. The number of Th17 and Treg cells was measured by flow cytometry before and after treatment for 6, 12 and 24 weeks. The SLE Disease Activity Index (SLEDAI) score and the prednisone dose before and after treatment were used to evaluate the efficacy between the two groups.

RESULTS

In both groups, at different time points after treatment, the number of Th17 cells (p = 0.003) and Th17/Treg ratio (p = 0.044) reduced, while the number of Treg cells (p = 0.574) tended to increase. The SLEDAI score and the dose of prednisone decreased significantly (p < 0.001). There was no significant difference in the number of Th17 cells (p = 0.089), Treg cells (p = 0.059), Th17/Treg ratio (p = 0.580), SLEDAI score (p = 0.127) and the dose of prednisone (p = 0.329) between the two groups.

CONCLUSION

Disease activity in SLE patients reduced with RAPA alone or in conjunction with ATRA, reducing glucocorticoid requirement. One of its mechanisms of action may be regulating the Th17/Treg cell balance, which provides a new model for the pathogenesis and potential treatment of SLE.

First Observation of an Attractive Interaction between a Proton and a Cascade Baryon

This Letter presents the first experimental observation of the attractive strong interaction between a proton and a multistrange baryon (hyperon) Ξ^{-}. The result is extracted from two-particle correlations of combined p-Ξ^{-}⊕p[over ¯]-Ξ[over ¯]^{+} pairs measured in p-Pb collisions at sqrt[s_{NN}]=5.02  TeV at the LHC with ALICE. The measured correlation function is compared with the prediction obtained assuming only an attractive Coulomb interaction and a standard deviation in the range [3.6, 5.3] is found. Since the measured p-Ξ^{-}⊕p[over ¯]-Ξ[over ¯]^{+} correlation is significantly enhanced with respect to the Coulomb prediction, the presence of an additional, strong, attractive interaction is evident. The data are compatible with recent lattice calculations by the HAL-QCD Collaboration, with a standard deviation in the range [1.8, 3.7]. The lattice potential predicts a shallow repulsive Ξ^{-} interaction within pure neutron matter and this implies stiffer equations of state for neutron-rich matter including hyperons. Implications of the strong interaction for the modeling of neutron stars are discussed.

Biological analysis of flexor tendon repair-failure stump tissue: A potential recycling of tissue for tendon regeneration

Objectives

Re-rupture is common after primary flexor tendon repair. Characterization of the biological changes in the ruptured tendon stumps would be helpful, not only to understand the biological responses to the failed tendon repair, but also to investigate if the tendon stumps could be used as a recycling biomaterial for tendon regeneration in the secondary grafting surgery.

Methods

A canine flexor tendon repair and failure model was used. Following six weeks of repair failure, the tendon stumps were analyzed and characterized as isolated tendon-derived stem cells (TDSCs).

Results

Failed-repair stump tissue showed cellular accumulation of crumpled and disoriented collagen fibres. Compared with normal tendon, stump tissue had significantly higher gene expression of collagens I and III, matrix metalloproteinases (MMPs), vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), and insulin-like growth factor (IGF). The stump TDSCs presented both mesenchymal stem and haematopoietic cell markers with significantly increased expression of CD34, CD44, and CD90 markers. Stump TDSCs exhibited similar migration but a lower proliferation rate, as well as similar osteogenic differentiation but a lower chondrogenic/adipogenic differentiation capability, compared with normal TDSCs. Stump TDSCs also showed increasing levels of SRY-box 2 (Sox2), octamer-binding transcription factor 4 (Oct4), tenomodulin (TNMD), and scleraxis (Scx) protein and gene expression.

Conclusion

We found that a failed repair stump had increased cellularity that preserved both mesenchymal and haematopoietic stem cell characteristics, with higher collagen synthesis, MMP, and growth factor gene expression. This study provides evidence that tendon stump tissue has regenerative potential.

Cite this article: C-C. Lu, T. Zhang, R. L. Reisdorf, P. C. Amadio, K-N. An, S. L. Moran, A. Gingery, C. Zhao. Biological analysis of flexor tendon repair-failure stump tissue: A potential recycling of tissue for tendon regeneration. Bone Joint Res 2019;8:232–245. DOI: 10.1302/2046-3758.86.BJR-2018-0239.R1.

Tests of General Relativity with GW170817

The recent discovery by Advanced LIGO and Advanced Virgo of a gravitational wave signal from a binary neutron star inspiral has enabled tests of general relativity (GR) with this new type of source. This source, for the first time, permits tests of strong-field dynamics of compact binaries in the presence of matter. In this Letter, we place constraints on the dipole radiation and possible deviations from GR in the post-Newtonian coefficients that govern the inspiral regime. Bounds on modified dispersion of gravitational waves are obtained; in combination with information from the observed electromagnetic counterpart we can also constrain effects due to large extra dimensions. Finally, the polarization content of the gravitational wave signal is studied. The results of all tests performed here show good agreement with GR.

Neuroimmune regulation of lung infection and inflammation

The distal airway of the lung is innervated by vagus nerve. Upon stimulation, vagus nerve endings release acetylcholine or neuropeptides via C-fiber afferents to regulate lung infection and immunity. Vagal sensory nerve endings, brain integration center, acetylcholine and α7 nicotinic acetylcholine receptor (nAChR) expressing cells are key components of pulmonary parasympathetic inflammatory reflex. Meanwhile, this local machinery synergizes with spleen (as a functional hub of cholinergic anti-inflammatory pathway) to finely tune recruitment of the splenic α7 nAChR+CD11b+ cells into the inflamed lungs during lung infection. Recent studies have showed that lung group 2 innate lymphoid cells (ILC2) express both α7 nAChR and neuropeptide receptors. Acetylcholine and neuropeptides can regulate ILC2 and reshape pulmonary infection and immunity. Among the airway epithelial cells, pulmonary neuroendocrine cells are rare cell population; however, these cells are innervated by sensory nerve endings and they could secrete neuropeptides that influence lung infection and immunity.

[Optical coherence tomography angiography of acute Vogt-Koyanagi-Harada disease]

Objective: To measure vascular density in retinal and choroidal capillary layers by optical coherence tomography angiography (OCTA) and to explore their potential clinical values in Vogt-Koyanagi-Harada disease (VKH). Methods: This is a cross-sectional case-control study. Twenty-one acute VKH cases presented to Peking Union Medical College Hospital between April 2015 and July 2015 and 49 healthy controls were enrolled in this study. OCTA was performed with a split-spectrum amplitude-decorrelation angiography-optical coherence tomography (SSADA-OCT) system borrowed from Optovue Inc. Vascular densities of the capillary layers were analyzed by the built-in software. Bilateral independent sample t-test was used to compare retinal and choroidal vascular density of eyes in acute phase VKH with healthy controls. Spearman correlation test was used to analyze the correlation between the vascular density of retina and choroid in acute phase VKH and LogMAR best corrected visual acuity (BCVA). Results: Mean vascular density of superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillaris (CC) in eyes of the acute VKH group were statistically lower than those of healthy control group (51.56%±2.88%, 56.51%±2.31%, 58.14%±2.10% vs. 53.55%±2.51%, 58.14%±2.10%, 58.14%±2.10%, t=-3.890, 3.910,-6.554, all 3 P values were<0.01). In VKH patients, eyes with retinal detachment (RD) had statistically lower mean vascular density in the CC layer than those without (NRD) (63.46%±2.19% vs. 65.85%±1.79%, t=3.890, P<0.01), while no statistically significant differences were found in vascular densities of SCP and DCP layers between RD and NRD eyes. Spearman's correlation test revealed a negative correlation between vascular density of the CC layer and logMAR BCVA(r=-0.437, P<0.01), while no statistically significant associations were found between logMAR BCVA and vascular densities of SCP and DCP. Conclusions: OCTA can be used for quantitative detection of vascular density of retina and choroidal capillary in acute VKH. There is circulatory disturbance in SCP, DCP and CC of acute VKH. Vascular density of CC is associated with visual acuity and retinal detachment. (Chin J Ophthalmol, 2017, 53: 735-739).

Making global river ecosystem health assessments objective, quantitative and comparable

Assessing and comparing global river ecosystem health in an objective and quantitative way remains a major challenge. In this study the widely-used semi-quantitative methods Rapid Biological assessment Protocols (RBPs) was used to determine the health of rivers. The findings were then compared to the results derived from our new UAV (Unmanned aerial vehicles) orthophotographic imagery method. This method quantitatively and objectively assesses river ecosystem health. As a comparison, our method was used to quantitatively measure distance and areas of a range of hydrological and biological attributes thus improving the accuracy of distance- and area-related indices, consequently avoiding subjective errors in these estimations that is fraught in methods like the RBPs. To strengthen the objectivity of the assessment the weights of these indices were objectively determined using the entropy weighting method. This new method was then tested using 9551 UAV orthophotographs taken over six field campaigns. It performed satisfactorily, showing that in our study area the health status of mountain rivers was the best with the highest score of 0.94 out of 1.0. Temporally, the health of the river was better in summer (0.65) compared with that in autumn (0.40). Changes in river ecosystem health were driven by variations in biology and water quality. In contrast the outputs of RBPs, especially in relation to distance and area indices, had ~ 20% uncertainty due to visual errors and subjectivity in estimations by observers. The UAV orthophotographic imaging method proposed in this study can improve the ability to compare the health of rivers across different periods and regions throughout the globe.

Two rare cases of maxillary pneumocoele

Pathological expansion of the paranasal sinus by air is rare, and may cause severe deformation of the overlying bone and tissue. We present two cases of young adults with maxillary pneumocoeles that were diagnosed by computed tomography, and discuss the differential aetiology.

Morphology control of extruded polystyrene foams with benzene-trisamide-based nucleating agents

Polystyrene is a low-priced, amorphous polymer, showing excellent foaming behavior. Polystyrene foams are widely used in a variety of applications including insulation panels for building and construction. In this context, foam morphology plays a significant role to tune the macroscopic properties of the foams and research focusses on the fabrication of foams with homogenous morphology and an average cell size distinctly below 100 µm at densities lower than 100 kg/m³. Here, we demonstrate how 1,3,5-benzene-trisamides can be used as supramolecular foam nucleating agents to control the morphology of extruded amorphous polystyrene foams. Depending on the concentration and the processing temperature, benzene-trisamides can be homogeneously dissolved in the polystyrene melt. Upon cooling, the benzene-trisamides self-assemble into finely dispersed, solid supramolecular nano-objects, which subsequently act as nucleating sites for foam cell formation. Various concentrations of the benzene-trisamide-based additive were selected to systematically study the influence of the morphology of the extruded polystyrene foams. In the same way, neat polystyrene foams were produced as a reference. We found that for extruded polystyrene foams with 0.2 wt% of additive, the cell sizes were significantly reduced by a factor of 35 from 632 to 18 µm compared to those of a neat extruded polystyrene reference foam.

Ultrasound-guided high-intensity focused ultrasound ablation for treating uterine arteriovenous malformation

OBJECTIVE

To explore HIFU treatment for uterine arteriovenous malformation.

DESIGN

A case report.

SETTING

Gynaecological department in a university teaching hospital of China.

POPULATION

A patient with uterine arteriovenous malformation.

METHODS

The diagnosis of uterine arteriovenous malformation was made through MRI. Ultrasound-guided high-intensity focused ultrasound (USgHIFU) ablation was performed.

MAIN OUTCOMES MEASURES

HIFU is effective in treating uterine arteriovenous malformation.

RESULTS

The patient had reduction of the lesion volume and obvious symptom relief, without significant adverse effects.

CONCLUSIONS

HIFU can be used as a new treatment option for uterine arteriovenous malformation.

TWEETABLE ABSTRACT

Ultrasound-guided high-intensity focused ultrasound ablation is effective in treating uterine arteriovenous malformation.

Anti-epidermal growth factor receptor (EGFR) monoclonal antibody combined with cisplatin and 5-fluorouracil in patients with metastatic nasopharyngeal carcinoma after radical radiotherapy: a multicentre, open-label, phase II clinical trial

BACKGROUND

We conducted a single-arm phase II trial to evaluate the efficacy and adverse effects (AEs) of an anti-epidermal growth factor receptor monoclonal antibody, nimotuzumab, combined with cisplatin and 5-fluorouracil (PF) as first-line treatment in recurrent metastatic nasopharyngeal carcinoma after radical radiotherapy.

METHODS

Patients who met the eligibility criteria were recruited from ten institutions (ClinicalTrials.gov; NCT01616849). A Simon optimal two-stage design was used to calculate the sample size. All patients received weekly nimotuzumab (200 mg) added to cisplatin (100 mg/m2 D1) and 5-fluorouracil (4 g/m2 continuous infusion D1-4) every 3-weekly for a maximum of six cycles. Primary end point was objective response rate (ORR). Secondary end points included disease control rate (DCR), progression-free survival (PFS), overall survival (OS) and AEs.

RESULTS

A total of 35 patients were enrolled (13 in stage 1 and 22 in stage 2). Overall ORR and DCR were 71.4% (25/35) and 85.7% (30/35), respectively. Median PFS and OS were 7.0 (95% CI 5.8-8.2) months and 16.3 (95% CI 11.4-21.3) months, respectively. Unplanned exploratory analyses suggest that patients who received ≥2400 mg nimotuzumab and ≥4 cycles of PF had superior ORR, PFS and OS than those who did not (88.9% versus 12.5%, P < 0.001; 7.4 versus 2.7 months, P = 0.081; 17.0 versus 8.0 months, P = 0.202). Favourable subgroups included patients with lung metastasis [HROS 0.324 (95% CI 0.146-0.717), P = 0.008] and disease-free interval of >12 months [HROS 0.307 (95% CI 0.131-0.724), P = 0.004], but no difference was observed for metastatic burden. The only major grade 3/4 AE was leukopenia (62.9%).

CONCLUSION

Combination nimotuzumab-PF chemotherapy demonstrates potential efficacy, and is well tolerated as first-line chemotherapy regimen in recurrent metastatic nasopharyngeal carcinoma.

A laser walk-off sensor for high-precision low-frequency rotation measurements

We present an optical walk-off sensor with an angular sensitivity of a few nrad/Hz above 1 mHz and 0.4 nrad/Hz above 100 mHz. This experiment furthers previous research into the walk-off sensor capabilities through an improved input laser, reduction in air optical travel length, and position control on photo-diodes. The angle change measured in this walk-off scheme features a knife edge to split the beam into two separate fiber coupled photo-diodes to minimize power dissipation in the thermally sensitive region. Using this photo-diode power differential as an error signal, a simple control scheme is used to maintain the balance position, increasing common mode rejection and improving dynamic range by mitigating thermal drift. The in-vacuum component of the optical readout takes up a volume less than 100 mm × 100 mm × 50 mm. This experiment shows that the walk-off sensor provides a simple and compact readout scheme with nanoradian sensitivity for angle sensing at low frequencies.

Ultra-deep next-generation sequencing of plasma cell-free DNA in patients with advanced lung cancers: results from the Actionable Genome Consortium

BACKGROUND

Noninvasive genotyping using plasma cell-free DNA (cfDNA) has the potential to obviate the need for some invasive biopsies in cancer patients while also elucidating disease heterogeneity. We sought to develop an ultra-deep plasma next-generation sequencing (NGS) assay for patients with non-small-cell lung cancers (NSCLC) that could detect targetable oncogenic drivers and resistance mutations in patients where tissue biopsy failed to identify an actionable alteration.

PATIENTS AND METHODS

Plasma was prospectively collected from patients with advanced, progressive NSCLC. We carried out ultra-deep NGS using cfDNA extracted from plasma and matched white blood cells using a hybrid capture panel covering 37 lung cancer-related genes sequenced to 50 000× raw target coverage filtering somatic mutations attributable to clonal hematopoiesis. Clinical sensitivity and specificity for plasma detection of known oncogenic drivers were calculated and compared with tissue genotyping results. Orthogonal ddPCR validation was carried out in a subset of cases.

RESULTS

In 127 assessable patients, plasma NGS detected driver mutations with variant allele fractions ranging from 0.14% to 52%. Plasma ddPCR for EGFR or KRAS mutations revealed findings nearly identical to those of plasma NGS in 21 of 22 patients, with high concordance of variant allele fraction (r = 0.98). Blinded to tissue genotype, plasma NGS sensitivity for de novo plasma detection of known oncogenic drivers was 75% (68/91). Specificity of plasma NGS in those who were driver-negative by tissue NGS was 100% (19/19). In 17 patients with tumor tissue deemed insufficient for genotyping, plasma NGS identified four KRAS mutations. In 23 EGFR mutant cases with acquired resistance to targeted therapy, plasma NGS detected potential resistance mechanisms, including EGFR T790M and C797S mutations and ERBB2 amplification.

CONCLUSIONS

Ultra-deep plasma NGS with clonal hematopoiesis filtering resulted in de novo detection of targetable oncogenic drivers and resistance mechanisms in patients with NSCLC, including when tissue biopsy was inadequate for genotyping.

Salt-Tolerant Superabsorbent Polymer with High Capacity of Water-Nutrient Retention Derived from Sulfamic Acid-Modified Starch

The application of superabsorbent polymers (SAPs) is hindered because their absorption capability is greatly affected by the electrolytes in a solution. A novel modified water-absorbent polymer was fabricated by solution polymerization of sulfamic acid-modified starch and acrylic acid; the swelling ratios of this absorbent polymer were 1026 g/g in deionized water and 145 g/g in 0.9% sodium chloride solution and increased by 99.5 and 13.4%, respectively, when compared with ordinary starch-grafted acrylic SAPs. The water absorption capacity was measured in water at different pH values, salt concentrations, and temperatures. In addition, water and fertilizer retentions were studied by simulated leaching tests in a soil column. The results showed that water absorption capacities of the modified SAP in salt solutions were improved due to the adsorption and transfer of water molecules by the sulfonic acid groups. Compared to the losses when there was no superabsorbent treatment, the water, nitrate, ammonium nitrogen, and water-soluble potassium losses during the salt-tolerant superabsorbent treatment were significantly reduced by 18.5, 22.8, 88.0, and 63.8%, respectively. The method introduced in this study could guide the development and wide application of salt-tolerant SAPs in agriculture and horticulture.

Azimuthal Anisotropy of Heavy-Flavor Decay Electrons in p-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

Angular correlations between heavy-flavor decay electrons and charged particles at midrapidity (|η|<0.8) are measured in p-Pb collisions at sqrt[s_{NN}]=5.02  TeV. The analysis is carried out for the 0%-20% (high) and 60%-100% (low) multiplicity ranges. The jet contribution in the correlation distribution from high-multiplicity events is removed by subtracting the distribution from low-multiplicity events. An azimuthal modulation remains after removing the jet contribution, similar to previous observations in two-particle angular correlation measurements for light-flavor hadrons. A Fourier decomposition of the modulation results in a positive second-order coefficient (v_{2}) for heavy-flavor decay electrons in the transverse momentum interval 1.5<p_{T}<4  GeV/c in high-multiplicity events, with a significance larger than 5σ. The results are compared with those of charged particles at midrapidity and those of inclusive muons at forward rapidity. The v_{2} measurement of open heavy-flavor particles at midrapidity in small collision systems could provide crucial information to help interpret the anisotropies observed in such systems.

Constraining the p-Mode-g-Mode Tidal Instability with GW170817

We analyze the impact of a proposed tidal instability coupling p modes and g modes within neutron stars on GW170817. This nonresonant instability transfers energy from the orbit of the binary to internal modes of the stars, accelerating the gravitational-wave driven inspiral. We model the impact of this instability on the phasing of the gravitational wave signal using three parameters per star: an overall amplitude, a saturation frequency, and a spectral index. Incorporating these additional parameters, we compute the Bayes factor (lnB_{!pg}^{pg}) comparing our p-g model to a standard one. We find that the observed signal is consistent with waveform models that neglect p-g effects, with lnB_{!pg}^{pg}=0.03_{-0.58}^{+0.70} (maximum a posteriori and 90% credible region). By injecting simulated signals that do not include p-g effects and recovering them with the p-g model, we show that there is a ≃50% probability of obtaining similar lnB_{!pg}^{pg} even when p-g effects are absent. We find that the p-g amplitude for 1.4  M_{⊙} neutron stars is constrained to less than a few tenths of the theoretical maximum, with maxima a posteriori near one-tenth this maximum and p-g saturation frequency ∼70  Hz. This suggests that there are less than a few hundred excited modes, assuming they all saturate by wave breaking. For comparison, theoretical upper bounds suggest ≲10^{3} modes saturate by wave breaking. Thus, the measured constraints only rule out extreme values of the p-g parameters. They also imply that the instability dissipates ≲10^{51}  erg over the entire inspiral, i.e., less than a few percent of the energy radiated as gravitational waves.

Dung-associated arthropods influence foraging ecology and habitat selection in Black-necked Cranes (Grus nigricollis) on the Qinghai-Tibet Plateau

Variation in grassland vegetation structure influences the habitat selection of insectivorous birds. This variation presents a trade-off for insectivorous predators: Arthropod abundance increases with vegetation height and heterogeneity, but access to arthropod prey items decreases. In contrast, grazing by large herbivores reduces and homogenizes vegetation, decreasing total arthropod abundance and diversity. However, the presence of livestock dung may help counteract the overall reduction in invertebrates by increasing arthropods associated with dung. It is unclear, however, how the presence of arthropod prey in dung contributes to overall habitat selection for insectivorous birds or how dung-associated arthropods affect trade-offs between vegetation structure, arthropod abundance, and access to prey. To explore these relationships, we studied habitat selection of the Black-necked Crane (Grus nigricollis), a large omnivorous bird that breeds on the Qinghai-Tibet Plateau. We assessed the relationships between habitat selection of cranes and vegetation structure, arthropod abundance, and the presence of yak dung. We found that Black-necked Cranes disproportionately foraged in grassland patches with short sward height, low sward height heterogeneity, and high numbers of dry yak dung, despite these habitats having lower total arthropod abundance. Although total arthropod abundance is lower, these habitats are supplemented with dry yak dung, which are associated with coleopteran larvae, making dung pats an indicator of food resources for breeding Black-necked Cranes. Coleopteran adults and larvae in yak dung appear to be an important factor influencing the habitat selection of Black-necked Cranes and should be considered when assessing grassland foraging trade-offs of insectivorous birds. This research provides new insights into the role of livestock dung in defining foraging habitats and resources for insectivorous predators.

Silencing of ATPase family AAA domain-containing protein 2 inhibits migration and invasion of colorectal cancer cells

Colorectal cancer is one of the most common malignant tumors with a high rate of distant metastasis, postoperative recurrence and mortality. ATPase family AAA domain-containing protein 2 (ATAD2), a member of ATPase family, is highly expressed in various cancers, including colorectal cancer. However, whether ATAD2 plays a role in the migration and invasion of colorectal cancer cells remains unknown. In this study, we established ATAD2 knockdown in colorectal cancer cell lines by RNA interference and found that silencing of ATAD2 inhibited the migration and invasion ability of Caco-2 and SW-480 cells. Moreover, ATAD2 silencing suppressed epithelial-mesenchymal transition (EMT), and reduced the expression and enzymatic activity of matrix metalloproteinases (MMPs) in Caco-2 and SW-480 cells. In summary, our results suggest that silencing of ATAD2 inhibits migration and invasion of colorectal cancer cells by suppressing EMT and decreasing the activity of MMPs. Hence, ATAD2 could be considered as a novel molecular marker of metastatic colorectal cancer, and it may provide new insights for clinical diagnosis and treatment of colorectal cancer.

Search for Subsolar-Mass Ultracompact Binaries in Advanced LIGO's First Observing Run

We present the first Advanced LIGO and Advanced Virgo search for ultracompact binary systems with component masses between 0.2  M_{⊙}-1.0  M_{⊙} using data taken between September 12, 2015 and January 19, 2016. We find no viable gravitational wave candidates. Our null result constrains the coalescence rate of monochromatic (delta function) distributions of nonspinning (0.2  M_{⊙}, 0.2  M_{⊙}) ultracompact binaries to be less than 1.0×10^{6}  Gpc^{-3}  yr^{-1} and the coalescence rate of a similar distribution of (1.0  M_{⊙}, 1.0  M_{⊙}) ultracompact binaries to be less than 1.9×10^{4}  Gpc^{-3}  yr^{-1} (at 90% confidence). Neither black holes nor neutron stars are expected to form below ∼1  M_{⊙} through conventional stellar evolution, though it has been proposed that similarly low mass black holes could be formed primordially through density fluctuations in the early Universe and contribute to the dark matter density. The interpretation of our constraints in the primordial black hole dark matter paradigm is highly model dependent; however, under a particular primordial black hole binary formation scenario we constrain monochromatic primordial black hole populations of 0.2  M_{⊙} to be less than 33% of the total dark matter density and monochromatic populations of 1.0  M_{⊙} to be less than 5% of the dark matter density. The latter strengthens the presently placed bounds from microlensing surveys of massive compact halo objects (MACHOs) provided by the MACHO and EROS Collaborations.

Angular instability in high optical power suspended cavities

Advanced gravitational wave detectors use suspended test masses to form optical resonant cavities for enhancing the detector sensitivity. These cavities store hundreds of kilowatts of coherent light and even higher optical power for future detectors. With such high optical power, the radiation pressure effect inside the cavity creates a sufficiently strong coupling between test masses whose dynamics are significantly altered. The dynamics of two independent nearly free masses become a coupled mechanical resonator system. The transfer function of the local control system used for controlling the test masses is modified by the radiation pressure effect. The changes in the transfer function of the local control systems can result in a new type of angular instability which occurs at only 1.3% of the Sidles-Sigg instability threshold power. We report the experimental results on a 74 m suspended cavity with a few kilowatts of circulating power, for which the power to mass ratio is comparable to the current Advanced LIGO. The radiation pressure effect on the test masses behaves like an additional optical feedback with respect to the local angular control, potentially making the mirror control system unstable. When the local angular control system is optimised for maximum stability margin, the instability threshold power increases from 4 kW to 29 kW. The system behaviour is consistent with our simulation, and the power dependent evolution of both the cavity soft and hard mode is observed. We show that this phenomenon is likely to significantly affect the proposed gravitational wave detectors that require very high optical power.

Mechanical stress contributes to osteoarthritis development through the activation of transforming growth factor beta 1 (TGF-β1)

Objectives

The role of mechanical stress and transforming growth factor beta 1 (TGF-β1) is important in the initiation and progression of osteoarthritis (OA). However, the underlying molecular mechanisms are not clearly known.

Methods

In this study, TGF-β1 from osteoclasts and knee joints were analyzed using a co-cultured cell model and an OA rat model, respectively. Five patients with a femoral neck fracture (four female and one male, mean 73.4 years (68 to 79)) were recruited between January 2015 and December 2015. Results showed that TGF-β1 was significantly upregulated in osteoclasts by cyclic loading in a time- and dose-dependent mode. The osteoclasts were subjected to cyclic loading before being co-cultured with chondrocytes for 24 hours.

Results

A significant decrease in the survival rate of co-cultured chondrocytes was found. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling (TUNEL) assay demonstrated that mechanical stress-induced apoptosis occurred significantly in co-cultured chondrocytes but administration of the TGF-β1 receptor inhibitor, SB-505124, can significantly reverse these effects. Abdominal administration of SB-505124 can attenuate markedly articular cartilage degradation in OA rats.

Conclusion

Mechanical stress-induced overexpression of TGF-β1 from osteoclasts is responsible for chondrocyte apoptosis and cartilage degeneration in OA. Administration of a TGF-β1 inhibitor can inhibit articular cartilage degradation.

Cite this article: R-K. Zhang, G-W. Li, C. Zeng, C-X. Lin, L-S. Huang, G-X. Huang, C. Zhao, S-Y. Feng, H. Fang. Mechanical stress contributes to osteoarthritis development through the activation of transforming growth factor beta 1 (TGF-β1). Bone Joint Res 2018;7:587–594. DOI: 10.1302/2046-3758.711.BJR-2018-0057.R1.

[Clinical features of glucocorticoid eye drops induced ocular hypertension in pediatric and adult uveitic eyes]

Objective: To investigate the clinical features of glucocorticoid eye drops induced ocular hypertension in pediatric and adult uveitic eyes. Methods: Retrospective survey of consecutive uveitic patients attending referral service at Peking Union Medical College Hospital from March 2013 to August 2017. Incidences of glucocorticoid eye drops induced ocular hypertension were compared between the pediatric and adult uveitic groups. The clinical patterns of 1% prednisolone acetate eye drops induced ocular hypertension in pediatric and adult uveitic eyes were also investigated. Data were analyzed using the Mann-Whitney test and the χ(2) test. Results: The clinical data of 1 138 uveitic eyes [677 patients; 331 males and 346 females; mean age (31±16) years]receiving corticosteroid eye drops were reviewed, among which 246 eyes (143 patients) had pediatric uveitis and 892 eyes (534 patients) had adult uveitis. The incidence of glucocorticoid eye drops induced ocular hypertension was higher in pediatric eyes (39.8%, 98/246) as compared to adults (29.1%, 260/892) (χ(2)=9.880, P=0.002). One hundred and thirty eyes (75 patients) with 1% prednisolone acetate induced ocular hypertension were included in the clinical pattern analysis, including 49 [28 patients; 15 males and 13 females; mean age (11±3) years] pediatric and 81 [47 patients; 22 males and 25 females;mean age (34±12) years] adult uveitic eyes. No differences were found in daily doses of 1% prednisolone acetate between the pediatric group [4.60 (3.46, 5.36) drops/day] and the adult group [4.00 (3.30, 4.88) drops/day; Z=-1.675, P=0.094]. But the duration of medication in pediatric eyes [4.71 (2.79, 6.36) weeks] was significantly shorter as compared to the adults [6.00 (4.86, 9.00) weeks; Z=-3.446, P<0.001]. The intraocular pressure (IOP) was 26.00 (24.00, 31.00) mmHg (1 mmHg=0.133 kPa) in pediatric uveitic eyes and 26.00 (23.30, 31.15) mmHg in the adults, which showed no statistical significance (Z=-0.231,P=0.818). To achieve effective IOP control, 79.6% (39/49) of pediatric and 54.3% (44/81) of adult eyes received IOP-lowering drug therapy (χ(2)=8.447,P=0.004). And during the follow-up, the withdrawal rate of IOP-lowering drugs was much lower in pediatric eyes (48.7%, 19/39) as compared to the adult group (72.7%, 32/44) (χ(2)=5.031, P=0.025). Conclusion: Compared with adult patients with uveitis, children with uveitis are more prone to IOP elevation, which is more difficult to control after the use of glucocorticoid eye drops. (Chin J Ophthalmol, 2018, 54: 839-842).

GW170817: Measurements of Neutron Star Radii and Equation of State

On 17 August 2017, the LIGO and Virgo observatories made the first direct detection of gravitational waves from the coalescence of a neutron star binary system. The detection of this gravitational-wave signal, GW170817, offers a novel opportunity to directly probe the properties of matter at the extreme conditions found in the interior of these stars. The initial, minimal-assumption analysis of the LIGO and Virgo data placed constraints on the tidal effects of the coalescing bodies, which were then translated to constraints on neutron star radii. Here, we expand upon previous analyses by working under the hypothesis that both bodies were neutron stars that are described by the same equation of state and have spins within the range observed in Galactic binary neutron stars. Our analysis employs two methods: the use of equation-of-state-insensitive relations between various macroscopic properties of the neutron stars and the use of an efficient parametrization of the defining function p(ρ) of the equation of state itself. From the LIGO and Virgo data alone and the first method, we measure the two neutron star radii as R_{1}=10.8_{-1.7}^{+2.0}  km for the heavier star and R_{2}=10.7_{-1.5}^{+2.1}  km for the lighter star at the 90% credible level. If we additionally require that the equation of state supports neutron stars with masses larger than 1.97  M_{⊙} as required from electromagnetic observations and employ the equation-of-state parametrization, we further constrain R_{1}=11.9_{-1.4}^{+1.4}  km and R_{2}=11.9_{-1.4}^{+1.4}  km at the 90% credible level. Finally, we obtain constraints on p(ρ) at supranuclear densities, with pressure at twice nuclear saturation density measured at 3.5_{-1.7}^{+2.7}×10^{34}  dyn cm^{-2} at the 90% level.

[Diagnostic value of D-dimer combined with Wells score for suspected pulmonary embolism]

OBJECTIVE

To evaluate the value of conventional and age-adjusted D-dimer cut-off value combined with 2-level Wells score for diagnosis of suspected pulmonary embolism.

METHODS

In the study, 335 patients with suspected pulmonary embolism who visited Peking University People's Hospital were enrolled retrospectively, then 274 patients with age over fifty years were chosen. The 2-level Wells score was applied to evaluate the clinical probability of pulmonary embolism, the diagnostic value of traditional D-dimer cut-off value (500 μg/L) and age adjusted D-dimer cut-off value (age×10 μg/L above 50 years) combined with Wells score no greater than 4 were compared. Computed tomography pulmonary arteriography (CTPA) was considered as the gold standard for diagnosis of pulmonary embolism.

RESULTS

(1) The area under a receiver operating characteristic (ROC) curve (AUC) in analysis of the combination of Wells score no greater than 4 and traditional D-dimer cut-off value was 0.764 (95%CI: 0.703-0.818). On the other hand, the AUC in a ROC analysis of the combination of Wells Score no greater than 4 and age-adjusted D-dimer cut-off value was 0.814 (95%CI:0.756-0.863). These two results did not differ statistically (Z=0.05, P=0.121). (2) The sensitivity, specificity, positive predictive value, negative predictive value and Youden index of the diagnosis of pulmonary embolism of the combination of traditional D-dimer cut-off value and 2-level Wells Score were 100%, 48.9%, 28.8%, 100%, and 0.49, respectively. Meanwhile, the sensitivity, specificity, positive predictive value, negative predictive value and Youden index of the diagnosis of pulmonary embolism of the combination of age-adjusted D-dimer cut-off value and 2-level Wells Score were 97.4%, 62.3%, 35.5%, 99.1%, and 0.60, respectively. Compared with using traditional D-dimer cut-off value, using age-adjusted D-dimer cut-off value could improve the diagnosis specificity (traditional D-dimer cut-off value group: 48.9%, age-adjusted D-dimer cut-off value group: 62.3%) of pulmonary embolism without reducing the sensitivity (traditional D-dimer cut-off value group: 100%, age-adjusted D-dimer cut-off value group: 99.1%). (3) Among the 222 patients with Wells Score no greater than 4, 90 patients were with D-dimer less than traditional cut-off value (500 μg/L), and 25 patients (account for 11.3% of all 222 patients) were with D-dimer between traditional cut-off value and age-adjusted cut-off value.

CONCLUSION

The application of age-adjusted D-dimer cut-off value can improve the diagnostic specificity of pulmonary embolism in patients over 50 years, without reducing the sensitivity. It can be used for ruling out suspected pulmonary embolism safely.

Co-Existence of Novel PDE6A Mutations and A Recurrent RPGR Mutation: A Potential Explanation for Phenotypic Diversity in Female RPGR Mutation Carriers

BACKGROUND

To report the co-existence of novel biallelic PDE6A mutations and heterozygous RPGR mutation in a Chinese female patient with retinitis pigmentosa (RP), and to analyze the intrafamilial phenotypic diversity.

METHODS

Three patients with retinopathy and four healthy family members were included in genetic and clinical analyses. Personal medical records were obtained from another four unaffected female family members who refused blood donation. Family history was carefully recorded. Each patient received comprehensive ophthalmic tests. Targeted next-generation sequencing (NGS) approach was performed on the proband to determine the retinopathy causative mutation for this family. In silico analysis was also applied to analyze the pathogenesis of identified mutations.

RESULTS

The two recruited male patients were diagnosed with RP, and the female patient RP sine pigmento (RPSP). Genetic assessments revealed a recurrent RPGR mutation, c.1926_1927insA, carried by all three patients and segregated the disease status. Three other unaffected female family members were confirmed as carriers for the identified RPGR mutation, and another four as obligate carriers. Interestingly, of all the eight female RPGR mutation carriers in this family, only one female developed retinal dystrophy. Comprehensive genetic analysis of this patient unraveled additional biallelic PDE6A mutations, c.[1066-9delT];[2324delG], carried solely by this individual.

CONCLUSIONS

Taken together, we hypothesize that the phenotypic variability presented by female RPGR mutation carriers may be attributed to the co-existence of other disease-causative mutations. Our study also emphasizes the importance of comprehensive genetic analysis in these female carriers, which will contribute to better diagnosis, prognosis, and treatment for these patients.

Deficiency of HIF-1α in myeloid cells protects Escherichia coli or LPS-induced acute lung injury

BACKGROUND

Deficiency of hypoxia-induced factor-1α (HIF-1α) in macrophages reduced lipopolysaccharide (LPS)-induced mortality; however, whether HIF-1α expression in myeloid cells would contribute to the development of Escherichia coli (E. coli) or LPS-induced acute lung injury (ALI) is less investigated.

AIM

To test whether deletion of Hif1α in myeloid cells affects E. coli or LPS-induced ALI and to elicit the underlying mechanisms.

DESIGN

Laboratory study.

METHODS

We intratracheally challenged Hif1αfl/fl and Hif1αfl/flLysMCre mice with E. coli or LPS to analyze lung and spleen inflammatory responses. Flow cytometry was used to analyze the changes of α7 nAChR+CD11b+ cells in the lung and spleen. Double knockout of Chrna7 and Itgam mice were used to examine expression of HIF-1α during E. coli lung infection. Vagotomy was performed to demonstrate the role of vagus nerve in mediating protective effects of deletion of Hif1α in myeloid cells on LPS-induced ALI.

RESULTS

Deletion of Hif1α in myeloid cells could reduce lung edema, inflammatory cell infiltration, and lung and BAL inflammatory cytokines in E. coli-induced ALI. Flow cytometric analysis revealed that α7 nAChR+CD11b+ cells in the lung and spleen were markedly increased in E. coli-challenged Hif1αfl/flLysMCre mice compared with E. coli-challenged Hif1αfl/fl mice. Double knockout of Chrna7 and Itgam increased HIF-1α expression in lung and spleen cells during lung E. coli infection. Vagotomy abolished the protective effect of deletion of Hif1α in myeloid cells on LPS-induced ALI.

CONCLUSION

Deletion of Hif1α in myeloid cells could protect mice from lung injury depending on α7 nAChR+CD11b+ cells and innervation of vagal circuits.