Local electronic structure of the peptide bond probed by resonant inelastic soft X-ray scattering

Soft X-ray emission spectroscopy and RIXS are used to determine the local electronic structure of the peptide bond.

[Clinical value of transcatheter arterial chemoembolization therapy for hepatocellular carcinoma with blood supply from right adrenal artery]

Objective: To study the clinical value of transcatheter arterial chemoembolization (TACE) therapy for hepatocellular carcinoma with blood supply from right adrenal artery. Methods: An imaging and clinical data of HCC patients with blood supply from right adrenal artery were collected from 2012 to 2016 after TACE treatment in the Second Affiliated Hospital of Chongqing Medical University and the safety and therapeutic efficacy of complete embolization therapy was analyzed retrospectively. Results: Twenty hepatocellular carcinoma patients with blood supply from right adrenal artery had received 23 times treatment. All lesions had invaded and protruded from the exogenous development of liver capsule. There were 14 cases with lesions > 5 cm in diameter. Right adrenal artery was found to be involved in the blood supply of three cases of hepatocellular carcinoma during TACE treatment for the first time. In addition, the remaining 17 cases had also received TACE treatment for the second to sixth time. The superior, middle, and inferior adrenal arteries were involved in 13, 3, and 9 cases, respectively. Twenty-four right adrenal arteries (96.0%) superselectively cannulated were successfully embolized without any serious complications. The standard method for evaluating the efficacy of liver cancer in 20 solid tumors follow-up cases showed that three cases were completely relieved, nine cases were partially relieved, two cases were stable, and six cases were progressive. The effective rate of embolization with blood supply from right adrenal artery lesions was 60.0%, and the control rate of lesion development was 70.0%. Conclusion: The right adrenal artery is mainly located in the S5-S7 segments of the liver. TACE features are obvious to ascertain its safety and effectiveness in the treatment of right adrenal artery tumors.

Discrete Superconducting Phases in FeSe-Derived Superconductors

A general feature of unconventional superconductors is the existence of a superconducting dome in the phase diagram. Here we report a series of discrete superconducting phases in the simplest iron-based superconductor, FeSe thin flakes, by continuously tuning the carrier concentration through the intercalation of Li and Na ions with a solid ionic gating technique. Such discrete superconducting phases are robust against the substitution of 20% S for Se, but they are vulnerable to the substitution of 2% Cu for Fe, highlighting the importance of the iron site being intact. The superconducting phase diagram for FeSe derivatives is given, which is distinct from that of other unconventional superconductors.

Landau Velocity for Collective Quantum Hall Breakdown in Bilayer Graphene

Breakdown of the quantum Hall effect (QHE) is commonly associated with an electric field approaching the inter-Landau-level (LL) Zener field, the ratio of the Landau gap and the cyclotron radius. Eluded in semiconducting heterostructures, in spite of extensive investigation, the intrinsic Zener limit is reported here using high-mobility bilayer graphene and high-frequency current noise. We show that collective excitations arising from electron-electron interactions are essential. Beyond a noiseless ballistic QHE regime a large super-Poissonian shot noise signals the breakdown via inter-LL scattering. The breakdown is ultimately limited by collective excitations in a regime where phonon and impurity scattering are quenched. The breakdown mechanism can be described by a Landau critical velocity as it bears strong similarities with the roton mechanism of superfluids. In addition, we show that breakdown is a precursor of an electric-field induced QHE-metal transition.

Detection and analysis of fine particulate matter and microbial aerosol in chicken houses in Shandong Province, China

Bacteria and fungi are primary constituents of airborne microbes in fine particulate matter and harmful to health. To evaluate the environmental quality of different poultry houses in Shandong Province, China, the airborne aerobic bacteria, airborne fungi, and airborne Escherichia coli were collected by the Andersen-6 air microorganism sampler. The fine particulate matter was collected by a ZR-3920 ambient air particulate matter sampler, and bacterial and fungal diversities and relative abundances analyzed using high-throughput sequencing. Results showed that the concentrations of airborne aerobic bacteria, airborne fungi, and airborne Escherichia coli in poultry houses were 0.167 to 4.484 × 104 CFU/m3, 0.236 to 4.735 × 103 CFU/m3, and 0 to 33.0 CFU/m3, respectively. 11.4 to 34.3% of aerobic bacteria and 16.8 to 37.5% of fungi were distributed at levels 5 and 6 (0.6 to 2.1 μm, the particle sizes similar to fine particulate matter) in the Andersen sampler. The concentration of fine particulate matter in the poultry houses was 114 to 230 μg/m3, which was higher than the safety value 10 specified by WHO. In fine particulate matter, the main bacteria at phylum level were Firmicutes, Bacteroidetes, and Proteobacteria, whereas the dominant phylum of fungus was Ascomycota and Basidiomycota. Importantly, the relative abundances of Escherichia and Corynebacterium in the broiler houses were greater than those in layer houses. However, the percentages of Aspergillus and Penicillium were 13.5 and 0.56%, with a relatively high level in the layer houses. Altogether, results revealed that the ambient air quality in the poultry houses sampled had a relatively high abundance of conditional pathogenic bacteria and concentration of fine particulate matter, which could threaten the health of animals and workers in those environments.

Ultrasensitive Displacement Noise Measurement of Carbon Nanotube Mechanical Resonators

Mechanical resonators based on a single carbon nanotube are exceptional sensors of mass and force. The force sensitivity in these ultralight resonators is often limited by the noise in the detection of the vibrations. Here, we report on an ultrasensitive scheme based on a RLC resonator and a low-temperature amplifier to detect nanotube vibrations. We also show a new fabrication process of electromechanical nanotube resonators to reduce the separation between the suspended nanotube and the gate electrode down to ∼150 nm. These advances in detection and fabrication allow us to reach [Formula: see text] displacement sensitivity. Thermal vibrations cooled cryogenically at 300 mK are detected with a signal-to-noise ratio as high as 17 dB. We demonstrate [Formula: see text] force sensitivity, which is the best force sensitivity achieved thus far with a mechanical resonator. Our work is an important step toward imaging individual nuclear spins and studying the coupling between mechanical vibrations and electrons in different quantum electron transport regimes.

Development and antimicrobial application of plantaricin BM-1 incorporating a PVDC film on fresh pork meat during cold storage

AIMS

The aim of this study was to develop a plantaricin BM-1, a typical IIa bacteriocin produced by Lactocacillus plantarumBM-1, for active polyvinylidene chloride (PVDC) films and to determine the antimicrobial effect of plantaricin BM-1 incorporated into a PVDC film on fresh pork during 7 days of storage at 4°C.

METHODS AND RESULTS

Plantaricin BM-1 solutions (20 480 AU ml^-1 ) that absorbed into the PVDC film increased gradually and reached maximum volumes during exposure for up to 20 h. When soaked in water, the released amount of plantaricin BM-1 from the active PVDC film reached a maximum at 20 h. The plantaricin BM-1 active PVDC film had an obvious antilisterial effect in culture medium and fresh pork inoculated with Listeria monocytogenes. Furthermore, plantaricin BM-1-incorporated PVDC film was also significantly (P < 0·01) reduced to aerobic counts of approximately 1·5 log₁₀ CFU per g after 7 days of storage at 4°C in pork meat, and the pH and total volatile basic nitrogen of pork meat were significantly (P < 0·01, P < 0·05) lower than those of the control.

CONCLUSION

Plantaricin BM-1 active film has an excellent effect to prolong the shelf life of pork meat during cold storage.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results of this study suggest a potential application of bacteriocin active film on meat preservation.

[An association of ulcerative colitis with tumor necrosis factor superfamily member 15 gene polymorphisms in Chinese patients]

Objective: To explore the relationship between ulcerative colitis (UC) susceptibility and tumor necrosis factor superfamily member (TNFSF) 15 gene polymorphisms and haplotypes in Han nationality in Zhejiang province of China. Methods: A total of 408 UC patients and 574 healthy controls were recruited in this study. Three single nucleotide polymorphisms of TNFSF15 (rs3810936, rs4263839, rs4979462) were examined by improved multiple ligase detection reaction (iMLDR) technique. Analyses of linkage disequilibrium (LD) and haplotype were performed by Haploview 4.2 software in all study subjects. Results: The variant allele A and genotype (GA+AA) of rs4263839 were less frequent in UC patients than in controls (45.34% vs. 50.17%, P=0.035;68.38% vs. 76.66%, P=0.004). According to the severity and location of disease, UC patients were divided into different subgroups. After multiple comparison correction(α=0.012 5), the frequencies of variant allele A and genotype (GA+AA) of rs4263839 were lower in patients with severe UC than in the controls (37.69% vs. 50.17%, P=0.007; 60.00% vs. 76.66%, P=0.004). Similar findings were also drawn for patients with extensive colitis in contrast with the controls (42.22% vs. 50.17%, P=0.009; 63.33% vs. 76.66%, P<0.001). Furthermore, the haplotype analysis indicated that three SNPs above were in a strong LD. The frequency of haplotype TAC was lower in UC patients than in the controls(40.83% vs. 46.04%, P=0.023). Also it was less prevalent in patients with severe UC and patients with extensive colitis when compared with controls respectively (33.38% vs. 46.04%, P=0.005;37.22% vs. 46.04%, P=0.003). Conclusions: TNFSF15 (rs4263839) variation might not only reduce the risk of UC, but also affect the severity and lesion location of UC. The haplotype TAC formed by rs3810936, rs4263839 and rs4979462 might be related to a lower risk of UC, especially in patients with severe colitis or patients with extensive colitis.

Improved performance of quantitative collagen parameters versus standard histology in longitudinal assessment of nonadvanced liver fibrosis for chronic hepatitis B

Monitoring longitudinal nonadvanced fibrosis is a more common scenario in management of chronic hepatitis B (CHB), for which, however, current evaluation methods generally lack sufficient performance. We conducted a proof-of-concept study to evaluate the performance of quantitative fibrous collagen parameters (q-FP) in the assessment. Data sets from a prior CHB trial (NCT00962533) with mostly mild-to-moderate fibrosis participants were used for this study. 301 subjects with paired liver biopsies were consecutively included. Of these, 139 subjects were used to establish the test and the rest for internal validation. Fibrosis change between baseline and week 104 of treatment was blindly assessed with q-FP and was compared with Ishak fibrosis staging. There were 70% and 93% subjects with Ishak F0-2 at baseline and week 104, respectively. For the test of the subjects, q-FP and Ishak staging showed no difference in determining the incidence of fibrosis regression (68% vs 67%; difference = 0.7%, P = 1.00). Q-FP demonstrated that the regression was independently associated with the antiviral efficacy endpoint (OR 3.0, 95% CI 1.4-6.5, P = .005), but Ishak failed the detection (OR 0.6, 95% CI 0.3-1.3, P = .24). Moreover, q-FP directly revealed a higher fibrosis-resistance to antiviral treatment in virus genotypes C vs B and in males vs females. These results were confirmed in the validation subjects. Additionally, a functional model built on the test subjects showed an accuracy of 82% in stratifying fibrosis reversibility of the validation subjects. In conclusion, q-FP could have improved efficiency and accuracy in the longitudinal assessment of mild-to-moderate CHB fibrosis, indicating a potential alternative to current evaluation methodologies.

Tuning the electrical and optical anisotropy of a monolayer black phosphorus magnetic superlattice

We investigate theoretically the effects of modulated periodic perpendicular magnetic fields on the electronic states and optical absorption spectrum in monolayer black phosphorus (phosphorene). We demonstrate that different phosphorene magnetic superlattice (PMS) orientations can give rise to distinct energy spectra, i.e. tuning the intrinsic electronic anisotropy. Rashba spin-orbit coupling (RSOC) develops a spin-splitting energy dispersion in this phosphorene magnetic superlattice. Anisotropic momentum-dependent carrier distributions along/perpendicular to the magnetic strips are demonstrated. The manipulations of these exotic electronic properties by tuning superlattice geometry, magnetic field and the RSOC term are addressed systematically. Accordingly, we find bright-to-dark transitions in the ground-state electron-hole pair transition rate spectrum and the PMS orientation-dependent anisotropic optical absorption spectrum. This feature offers us a practical way of modulating the electronic anisotropy in phosphorene by magnetic superlattice configurations and detecting this modulation capability by using an optical technique.

Cell therapy of a knee osteoarthritis rat model using precartilaginous stem cells

OBJECTIVE

To explore the effect and mechanism of precartilaginous stem cells (PSCs) engraftment-inducing tissue repair in a knee osteoarthritis (OA) rat model.

MATERIALS AND METHODS

Knee osteoarthritis (OA) model was constructed in Sprague Dawley (SD) rats by partial removal of the medial meniscus of the right knee. PSCs were engrafted by injecting precartilaginous stem cells (PSCs) into the right knee cavity. At 4 and 8 weeks after model construction, the serum levels of interleukine (IL)-1β, tumor necrosis factor (TNF)-α, and IL-6 were assessed using enzyme-linked immunosorbent assay (ELISA). Hematoxylin-eosin (HE) staining was performed to assess the histopathology of synovial membrane and cartilage. Western blot analysis was used to assess Notch1, Bcl-2 and Bax levels in the articular cartilage.

RESULTS

At 4 and 8 weeks, OA rats demonstrated significantly higher IL-1β, TNF-α, and IL-6 levels than normal rats (p < 0.05), whereas PSCs treatment prominently attenuated IL-1β upregulation (p < 0.05). In OA rats, the number of chondrocytes dramatically decreased over time in OA rats, with disruption of chondrocytes organization and cell layers. PSCs alleviated the deterioration of cartilage, as evidenced by the relatively smooth articular surface, distinct tidemark and clear cell layers. The model and treatment groups demonstrated substantially higher Notch1 expression. The Bcl-2/Bax value in the OA rats was lower than the control group, while PSCs treatment led to increase in Bcl-2/Bax value.

CONCLUSIONS

PSCs treatment downregulated the expression of inflammatory cytokines, alleviating osteoarthritis in the knee of rats. Notch1 signaling pathway plays an important role in this ameliorating effect of PSCs treatment.

Warthin's tumour in oral and maxillofacial regions: an 18-year retrospective study of 1084 cases in an eastern-Chinese population

There is little information in the English-language literature regarding Warthin's tumour (WT) in the eastern-Chinese population. A large retrospective study (1084 primary tumours over a period of 18years) was carried out to investigate the clinicopathological features (patients' gender, age and tumour location) of these tumours in this population. A total of 994 (91.7%) patients were male and 90 (8.3%) were female, with a male/female ratio of 11:1. The mean age was 56.48years (range 20-89years), with a peak incidence in the fifth to seventh decade (82.1%). The favorite primary site of the tumour was the parotid gland (n=1055), followed by intra-/peri-parotid lymph nodes (n=13), upper neck (n=10), submandibular gland (n=4) and upper lip (n=1). Multifocal WTs arose in 9.5% (103 patients) of cases whereas bilateral multifocal WTs were found in 0.65% (seven patients). In 24 (2.2%) patients, WT were found to coexist with other different types of neoplasm synchronously. The most common subtype of metaplasia was the squamous metaplasia (166/250, 66.4%). The usual treatment measure is (bilateral) superficial parotidectomy and the patients should be followed long term, in view of possible metachronous WT, even after prolonged time intervals.