Novel Measurement of the Neutron Magnetic Form Factor from A=3 Mirror Nuclei

The electromagnetic form factors of the proton and neutron encode information on the spatial structure of their charge and magnetization distributions. While measurements of the proton are relatively straightforward, the lack of a free neutron target makes measurements of the neutron's electromagnetic structure more challenging and more sensitive to experimental or model-dependent uncertainties. Various experiments have attempted to extract the neutron form factors from scattering from the neutron in deuterium, with different techniques providing different, and sometimes large, systematic uncertainties. We present results from a novel measurement of the neutron magnetic form factor using quasielastic scattering from the mirror nuclei ^{3}H and ^{3}He, where the nuclear effects are larger than for deuterium but expected to largely cancel in the cross-section ratios. We extracted values of the neutron magnetic form factor for low-to-modest momentum transfer, 0.6 Collapse

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Deeply Virtual Compton Scattering Cross Section at High Bjorken x_{B}

We report high-precision measurements of the deeply virtual Compton scattering (DVCS) cross section at high values of the Bjorken variable x_{B}. DVCS is sensitive to the generalized parton distributions of the nucleon, which provide a three-dimensional description of its internal constituents. Using the exact analytic expression of the DVCS cross section for all possible polarization states of the initial and final electron and nucleon, and final state photon, we present the first experimental extraction of all four helicity-conserving Compton form factors (CFFs) of the nucleon as a function of x_{B}, while systematically including helicity flip amplitudes. In particular, the high accuracy of the present data demonstrates sensitivity to some very poorly known CFFs.

Form Factors and Two-Photon Exchange in High-Energy Elastic Electron-Proton Scattering

We present new precision measurements of the elastic electron-proton scattering cross section for momentum transfer (Q^{2}) up to 15.75  (GeV/c)^{2}. Combined with existing data, these provide an improved extraction of the proton magnetic form factor at high Q^{2} and double the range over which a longitudinal or transverse separation of the cross section can be performed. The difference between our results and polarization data agrees with that observed at lower Q^{2} and attributed to hard two-photon exchange (TPE) effects, extending to 8  (GeV/c)^{2} the range of Q^{2} for which a discrepancy is established at >95% confidence. We use the discrepancy to quantify the size of TPE contributions needed to explain the cross section at high Q^{2}.

Deep Exclusive Electroproduction of π^{0} at High Q^{2} in the Quark Valence Regime

We report measurements of the exclusive neutral pion electroproduction cross section off protons at large values of x_{B} (0.36, 0.48, and 0.60) and Q^{2} (3.1 to 8.4  GeV^{2}) obtained from Jefferson Lab Hall A experiment E12-06-014. The corresponding structure functions dσ_{T}/dt+εdσ_{L}/dt, dσ_{TT}/dt, dσ_{LT}/dt, and dσ_{LT^{'}}/dt are extracted as a function of the proton momentum transfer t-t_{min}. The results suggest the amplitude for transversely polarized virtual photons continues to dominate the cross section throughout this kinematic range. The data are well described by calculations based on transversity generalized parton distributions coupled to a helicity flip distribution amplitude of the pion, thus providing a unique way to probe the structure of the nucleon.

Clinical characteristics, treatment strategies and oncologic outcomes of primary retroperitoneal tumours: a retrospective analysis in the Chinese population

INTRODUCTION

Primary retroperitoneal tumours (PRTs) are rare soft tissue tumours originating from the retroperitoneum. Although there has been considerable progress recently in diagnosis and treatment, the overall survival rate has not improved qualitatively. This study aimed to explore the clinical features, therapeutic strategies and prognosis of PRTs.

METHODS

Retrospective analysis of clinical data for 121 PRT patients admitted to Peking University Shenzhen Hospital from April 2003 to February 2017.

RESULTS

A total of 113 patients underwent surgery and 8 chose nonsurgical palliative treatment. There were 53 males and 68 females (ratio, 1:1.3; average age, 40.75 years), and the average tumour diameter was 9.69(2-40)cm. A total of 104 patients (92.04%) underwent complete resection, 5 (4.42%) underwent palliative resection and 21 (18.58%) underwent combined visceral resection. The pathological diagnosis was benign in 88 cases (72.73%) and malignant in 33 cases (27.27%). A total of 101 patients (83.47%) were followed for an average of 5.82 years. At the end of follow up, the recurrence and survival rates were 2.63% and 93.42% for benign tumours, respectively, and 24.00% and 60.00% for malignant tumours (p<0.01).

CONCLUSIONS

Imaging plays important roles in localising and characterising tumours, guiding treatment strategies. Complete tumour resection is key to reducing postoperative recurrence and improving survival. According to the postsurgical pathological results, combinations including radiotherapy, chemotherapy or targeted therapy are beneficial for improving prognosis.

Reduced long non-coding RNA PTENP1 contributed to proliferation and invasion via miR-19b/MTUS1 axis in patients with cervical cancer

OBJECTIVE

Many studies showed that long non-coding RNAs (lncRNAs) may serve as prospective markers for patients with malignant cancers, including cervical cancer (CC). In this study, we mainly investigate the functions of lncRNA PTENP1 in the progression of human CC.

MATERIALS AND METHODS

Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to detect expression levels of PTENP1, miR-19b and MTUS1 in CC tissues, the adjacent tissues and CC cell lines. The correlations between PTENP1 with miR-19b, miR-19b with MTUS1 and PTENP1 with MTUS1 were analyzed. Overall survival (OS) of patients was analyzed using Kaplan-Meier method. Proliferation capacity was measured by CCK-8 assay and the invasion ability in CC cell line was detected by transwell assay. Western blot (WB) assay was performed to measure protein levels of tissues and CC cell lines. Finally, Dual-Luciferase reporter assay was performed to prove the potential binding sites between PTENP1 and miR-19b, miR-19b and MTUS1.

RESULTS

We found that PTENP1 was reduced in CC tissues and CC cell lines, which predicted the poor diagnosis of CC patients. MiR-19b was increased in CC tissues, which was negatively correlated with PTENP1 in CC tissues. MTUS1 was reduced in CC tissues, which was negatively correlated with miR-19b and positively correlated within PTENP1 CC tissues. Furthermore, PTENP1 overexpression inhibited cell proliferation ability and invasion capacity in HeLa cells, as well as repressed expressions of Cyclin D1, N-cadherin, and Vimentin. Moreover, Luciferase gene reporter assays verified that miR-19b was a direct target miRNA of PTENP1, and MTUS1 was identified as a direct target of miR-19b. In addition, the inhibited cell proliferation and invasion abilities in HeLa cells with p-PTENP1 were eliminated following with miR-19b mimic transfection.

CONCLUSIONS

According to the results, this study showed that PTENP1 was reduced in CC patients and it was a prognostic factor for CC patients. Furthermore, we firstly uncovered that PTENP1 could inhibit cell proliferation and invasion via miR-19b/MTUS1 in CC patients, which uncovered the tumor-suppressive role of PTENP1 in CC and suggested that it might be a potential target for treating human CC.

Probing Few-Body Nuclear Dynamics via ^{3}H and ^{3}He (e,e^{'}p)pn Cross-Section Measurements

We report the first measurement of the (e,e^{'}p) three-body breakup reaction cross sections in helium-3 (^{3}He) and tritium (^{3}H) at large momentum transfer [⟨Q^{2}⟩≈1.9  (GeV/c)^{2}] and x_{B}>1 kinematics, where the cross section should be sensitive to quasielastic (QE) scattering from single nucleons. The data cover missing momenta 40≤p_{miss}≤500  MeV/c that, in the QE limit with no rescattering, equals the initial momentum of the probed nucleon. The measured cross sections are compared with state-of-the-art ab initio calculations. Overall good agreement, within ±20%, is observed between data and calculations for the full p_{miss} range for ^{3}H and for 100≤p_{miss}≤350  MeV/c for ^{3}He. Including the effects of rescattering of the outgoing nucleon improves agreement with the data at p_{miss}>250  MeV/c and suggests contributions from charge-exchange (SCX) rescattering. The isoscalar sum of ^{3}He plus ^{3}H, which is largely insensitive to SCX, is described by calculations to within the accuracy of the data over the entire p_{miss} range. This validates current models of the ground state of the three-nucleon system up to very high initial nucleon momenta of 500  MeV/c.

Harnessing the anti-cancer natural product nimbolide for targeted protein degradation

Nimbolide, a terpenoid natural product derived from the Neem tree, impairs cancer pathogenicity; however, the direct targets and mechanisms by which nimbolide exerts its effects are poorly understood. Here, we used activity-based protein profiling (ABPP) chemoproteomic platforms to discover that nimbolide reacts with a novel functional cysteine crucial for substrate recognition in the E3 ubiquitin ligase RNF114. Nimbolide impairs breast cancer cell proliferation in-part by disrupting RNF114 substrate recognition, leading to inhibition of ubiquitination and degradation of the tumor-suppressors such as p21, resulting in their rapid stabilization. We further demonstrate that nimbolide can be harnessed to recruit RNF114 as an E3 ligase in targeted protein degradation applications and show that synthetically simpler scaffolds are also capable of accessing this unique reactive site. Our study highlights the utility of ABPP platforms in uncovering unique druggable modalities accessed by natural products for cancer therapy and targeted protein degradation applications.

SAAMP 2.0: An algorithm to predict genotype-phenotype correlation of lysosomal storage diseases

Lysosomal storage diseases (LSDs) are a group of genetic disorders, resulting from deficiencies of lysosomal enzyme. Genotype-phenotype correlation is essential for timely and proper treatment allocation. Recently, by integrating prediction outcomes of 7 bioinformatics tools, we developed a SAAMP algorithm to predict the impact of individual amino-acid substitution. To optimize this approach, we evaluated the performance of these bioinformatics tools in a broad array of genes. PolyPhen and PROVEAN had the best performances, while SNP&GOs, PANTHER and I-Mutant had the worst performances. Therefore, SAAMP 2.0 was developed by excluding 3 tools with worst performance, yielding a sensitivity of 94% and a specificity of 90%. To generalize the guideline to proteins without known structures, we built the three-dimensional model of iduronate-2-sulfatase by homology modeling. Further, we investigated the phenotype severity of known disease-causing mutations of the GLB1 gene, which lead to 2 LSDs (GM1 gangliosidosis and Morquio disease type B). Based on the previous literature and structural analysis, we associated these mutations with disease subtypes and proposed a theory to explain the complicated genotype-phenotype correlation. Collectively, an updated guideline for phenotype prediction with SAAMP 2.0 was proposed, which will provide essential information for early diagnosis and proper treatment allocation, and they may be generalized to many monogenic diseases.

Transmission of megawatt relativistic electron beams through millimeter apertures

High-power, relativistic electron beams from energy-recovering linacs have great potential to realize new experimental paradigms for pioneering innovation in fundamental and applied research. A major design consideration for this new generation of experimental capabilities is the understanding of the halo associated with these bright, intense beams. In this Letter, we report on measurements performed using the 100 MeV, 430 kW cw electron beam from the energy-recovering linac at the Jefferson Laboratory's Free Electron Laser facility as it traversed a set of small apertures in a 127 mm long aluminum block. Thermal measurements of the block together with neutron measurements near the beam-target interaction point yielded a consistent understanding of the beam losses. These were determined to be 3 ppm through a 2 mm diameter aperture and were maintained during a 7 h continuous run.

EDHF contributes to strain-related differences in pulmonary arterial relaxation in rats

Pulmonary arteries from the Madison (M) strain relax more in response to acetylcholine (ACh) than those from the Hilltop (H) strain of Sprague-Dawley rats. We hypothesized that differences in endothelial nitric oxide (NO) synthase (eNOS) expression and function, metabolism of ACh by cholinesterases, release of prostacyclin, or endothelium-derived hyperpolarizing factor(s) (EDHF) from the endothelium would explain the differences in the relaxation response to ACh in isolated pulmonary arteries. eNOS mRNA and protein levels as well as the NO-dependent relaxation responses to thapsigargin in phenylephrine (10(-6) M)-precontracted pulmonary arteries from the M and H strains were identical. The greater relaxation response to ACh in M compared with H rats was also observed with carbachol, a cholinesterase-resistant analog of ACh, a response that was not modified by pretreatment with meclofenamate (10(-5) M). N(omega)-nitro-L-arginine (10(-4) M) completely abolished carbachol-induced relaxation in H rat pulmonary arteries but not in M rat pulmonary arteries. Precontraction with KCl (20 mM) blunted the relaxation response to carbachol in M rat pulmonary arteries and eliminated differences between the M and H rat pulmonary arteries. NO-independent relaxation present in the M rat pulmonary arteries was significantly reduced by 17-octadecynoic acid (2 microM) and was completely abolished by charybdotoxin plus apamin (100 nM each). These findings suggest that EDHF, but not NO, contributes to the strain-related differences in pulmonary artery reactivity. Also, EDHF may be a metabolite of cytochrome P-450 that activates Ca(2+)-dependent K(+) channels.

[Effects of autogenous periodontal ligament cell transplantation on periodontal tissue regeneration in dogs]

OBJECTIVE

To evaluate the effect of autogenous periodontal ligament cell (PDL) transplantation in periodontal tissue regeneration.

METHODS

PDL cells derived from the same dog were cultured with alpha-MEM. 1 x 10(5) cells of first passage were allowed to attach to the collagen membrane for 24 hours. The membrane-cells were transplanted into periodontal defect in the same dog. Then the defects were covered with e-PTFE membranes. The defects covered only with e-PTFE were the controls. Eighteen teeth of 6 dogs for each group were included. The dogs were sacrificed after 6 weeks.

RESULTS

The results showed that new bone formation (4.00 +/- 0.13) mm in test group was significantly higher than that of in control group (3.09 +/- 0.28) mm, P < 0.05. The new cementum formation in test group was better than control group (P < 0.05).

CONCLUSION

The results suggested that PDL cell transplantation with guided tissue regeneration technique could enhance periodontal tissue regeneration in dogs.

[Effect of age on mineralization expression of periodontal ligament cell clones]

OBJECTIVE

To evaluate the effect of age on the expression of mineralized tissue progenitors in the peridontium and the effect of basic fibroblast growth factor (bFGF).

METHODS

The periodontal ligament (PDL) tissues that derived from three old and 4 young donors were cultured and cells were cloned. The mineralizing ability were detected with or without bFGF treatment in the presence of dexamethasone. The cell cloning technic was employed in present study.

RESULTS

The results indicated that the frequency of mineralized tissue progenitors (old donor: 4.1%) and the numbers of cell clones that mineralized with bFGF treated in the PDL cultures derived from old donors (3.4%) is considerably less than that of cultures obtained from young donors (17.7% and 16.9%). bFGF enhanced the mineralization of cell clone but not the parent population.

CONCLUSION

It is concluded that the poor stem cell and progenitors in PDL and the low reaction of progenitors to growth factors in PDL are responsible for the limited regenerative capacity of periodontium in old patient.

Degradation of Fenamiphos Sulfoxide and Fenamiphos Sulfone in Soil with a History of Continuous Applications of Fenamiphos

Mineralization rates of fenamiphos sulfoxide (FSO), total-toxic-residue [TTR, FSO+fenamiphos sulfone (FSO2)] disappearance rates for FSO, disappearance rates of FSO2, and metabolites in surface and subsurface soil samples collected from a turfgrass site (fairway) were determined. This site had been treated with fenamiphos annually or biannually for 20 years, and enhanced degradation of fenamiphos TTR was observed. Both the mineralization of FSO and the disappearance of FSO TTR, as well as the disappearance of FSO2 in soil samples collected from the fairway were much more rapid than in soil samples collected from a nearby site (rough) that had no previous history of fenamiphos application. Both FSO and FSO2 were degraded more rapidly in surface soil samples than in subsurface samples. The degradation pathway of FSO in the fairway soil samples was different from the rough samples. Hydrolysis to FSO phenol (FSO-OH) was the initial route of degradation of FSO in the fairway samples, whereas hydrolysis to FSO-OH and oxidation to FSO2 were the initial routes of degradation in the rough samples.

Identification of adenosine receptor in rat pineal gland: evidence for A-2 selectivity

We have examined the binding of the adenosine agonist radioligands [3H]cyclohexyladenosine [( 3H]CHA), R-N6-[3H]phenylisopropyladenosine [( 3H]R-PIA), and 5'-N-ethylcarboxamido[3H]adenosine [( 3H]NECA) to membranes prepared from rat pineal gland. The results showed that the A-1-selective ligands (CHA and R-PIA) had less than or equal to 10% specific binding. By contrast, [3H]NECA, a nonselective A-1/A-2 ligand, gave 72% specific binding of the total binding. This specific binding was insensitive to cyclopentyladenosine (50 nM) or R-PIA (50 microM). To characterize this binding, we used the N-ethylmaleimide pretreatment method. Under these conditions, this binding was of high affinity with a KD of 51 +/- 10 nM and an apparent Bmax of 1,060 +/- 239 fmol/mg of protein. Specific binding was unaffected by the presence of MgCl2 (10 mM) but was sensitive to guanylylimidodiphosphate (100 microM) (-25%), a result suggesting the involvement of an N-protein mechanism in the coupling of the adenosine receptor labeled by [3H]NECA to other components of the receptor complex. The rank of activity of adenosine analogues in displacing specific [3H]NECA binding was NECA greater than 2-chloroadenosine greater than S-adenosyl-L-homocysteine greater than CHA. Binding was also displaced by 3-isobutyl-1-methylxanthine (IC50 = 23.6 microM). These findings are consistent with the selective labeling by [3H]NECA of an A-2-type adenosine receptor in rat pineal membranes.

Method for measuring increased plasma hemoglobin in the presence of erythrocytes

Despite its many drawbacks the classic benzidine technique is the method most widely used for determining plasma hemoglobin. An additional disadvantage, reported here, is that the method measures hemoglobin in erythrocytes as well as in plasma. Thus, if plasma specimens are accidentally contaminated with erythrocytes, apparent free hemoglobin in plasma will be artifactually high. Although the present method lacks the sensitivity of the benzidine technique, it self-corrects for the presence of erythrocytes. We have found it particularly useful for specimens of rodent (rat mouse) blood, where some cells appear to resist centrifugation, where the small sample sizes frequently result in accidental contamination of plasma with cells, and where normal values may be higher than those for human plasma.

Method for measuring increased plasma hemoglobin in the presence of erythrocytes

Despite its many drawbacks the classic benzidine technique is the method most widely used for determining plasma hemoglobin. An additional disadvantage, reported here, is that the method measures hemoglobin in erythrocytes as well as in plasma. Thus, if plasma specimens are accidentally contaminated with erythrocytes, apparent free hemoglobin in plasma will be artifactually high. Although the present method lacks the sensitivity of the benzidine technique, it self-corrects for the presence of erythrocytes. We have found it particularly useful for specimens of rodent (rat mouse) blood, where some cells appear to resist centrifugation, where the small sample sizes frequently result in accidental contamination of plasma with cells, and where normal values may be higher than those for human plasma.