We report a theoretical study of the electronic structure and optical properties of free-standing semiconductor nanowires, based on an atomistic tight-binding approach. It is shown that the optical ...transition between the valence-band maximum and conduction-band minimum of an intrinsic nanowire is fully polarized along the wire axis, and this giant polarization anisotropy can be explained in terms of intrinsic band-structure properties of the nanowire. It is also predicted that the optical spectra and polarization ratio of the nanowire can be tuned with temperature and the chemical potential of carriers in the nanowire.
We report results of a search for light dark matter weakly interacting massive particles (WIMPs) with CDEX-1 experiment at the China Jinping Underground Laboratory, based on 53.9 kg-days of data from ...a p-type point-contact germanium detector enclosed by a Nal(TI) crystal scintillator as anti-Compton detector. The event rate and spectrum above the analysis threshold of 475 eVee are consistent with the understood background model. Part of the allowed regions for WIMP-nucleus coherent elastic scattering at WIMP mass of 6-20 GeV are probed and excluded. Independent of interaction channels, this result contradicts the interpretation that the anomalous excesses of the CoGeNT experiment are induced by dark matter, since identical detector techniques are used in both experiments.
The gut microbiome has been suggested to play a role in gut barrier hemostasis, but data are scarce and limited to animal studies. We therefore aimed to assess whether alterations in gut microbial ...composition and functional pathways are associated with gut barrier function in a cohort of healthy first-degree relatives of patients with Crohn’s disease.
We used the Crohn's and Colitis Canada Genetic Environmental Microbial (CCC-GEM) cohort of healthy first-degree relatives of patients with Crohn’s disease. Gut barrier function was assessed using the urinary fractional excretion of lactulose-to-mannitol ratio (LMR). Microbiome composition was assessed by sequencing fecal 16S ribosomal RNA. The cohort was divided into a discovery cohort (n = 2472) and a validation cohort (n = 655). A regression model was used to assess microbial associations with the LMR. A random forest classifier algorithm was performed to assess microbial community contribution to barrier function.
Individuals with impaired barrier function (LMR >0.025) had reduced alpha-diversity (Chao1 index, P = 4.0e−4) and altered beta-diversity (Bray-Curtis dissimilarity index, R2 = 0.001, P = 1.0e−3) compared with individuals with an LMR ≤0.025. When taxa were assessed individually, we identified 8 genera and 52 microbial pathways associated with an LMR >0.025 (q < 0.05). Four genera (decreased prevalence of Adlercreutzia, Clostridia UCG 014, and Clostridium sensu stricto 1 and increased abundance of Colidextribacter) and 8 pathways (including decreased biosynthesis of glutamate, tryptophan, and threonine) were replicated in the validation cohort. The random forest approach revealed that the bacterial community is associated with gut barrier function (area under the curve, 0.63; P = 1.4e−6).
The gut microbiome community and pathways are associated with changes in gut barrier function. These findings may identify potential microbial targets to modulate gut barrier.
Display omitted
Alterations in gut microbiome are associated with gut barrier dysfunction in healthy humans.
Acute promyelocytic leukemia (APL) is characterized by a specific chromosome translocation involving RARα and one of four fusion partners: PML, PLZF, NPM, and NuMA genes. To study the leukemogenic ...potential of the fusion genes in vivo, we generated transgenic mice with PLZF-RARα and NPM-RARα . PLZF-RARα transgenic animals developed chronic myeloid leukemia-like phenotypes at an early stage of life (within 3 months in five of six mice), whereas three NPM-RARα transgenic mice showed a spectrum of phenotypes from typical APL to chronic myeloid leukemia relatively late in life (from 12 to 15 months). In contrast to bone marrow cells from PLZF-RARα transgenic mice, those from NPM-RARα transgenic mice could be induced to differentiate by all-trans-retinoic acid (ATRA). We also studied RARE binding properties and interactions between nuclear corepressor SMRT and various fusion proteins in response to ATRA. Dissociation of SMRT from different receptors was observed at ATRA concentrations of 0.01 μ M, 0.1 μ M, and 1.0 μ M for RARα -RXRα , NPM-RARα , and PML-RARα , respectively, but not observed for PLZF-RARα even in the presence of 10 μ M ATRA. We also determined the expression of the tissue factor gene in transgenic mice, which was detected only in bone marrow cells of mice expressing the fusion genes. These data clearly establish the leukemogenic role of PLZF-RARα and NPM-RARα and the importance of fusion receptor/corepressor interactions in the pathogenesis as well as in determining different clinical phenotypes of APL.
To evaluate the prognosis of visual function and the impact of surgery in pediatric patients with sellar mass lesions, as evidenced by diffusion tensor imaging (DTI) and visual evoked potentials.
...Twenty patients with sellar mass lesions were included in the study. DTI and visual evoked potentials were obtained before and after surgery. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were calculated for both optic nerves. DTI parameters and visual evoked potential amplitudes were compared for all patients to assess the correlation between DTI parameters and visual function.
The 20 patients were divided into two groups according the relationship between the lesions and the optic chiasm. The FA values increased significantly after operation, while the ADC values decreased (
<0.05). And the average amplitude of visual evoked potentials after operation was significantly higher than before operation (
0.05).
DTI assessments of the affected sides, with the resulting FA and ADC values, may
The uptake of Cs(I) on Beishan soil (BS) was strongly dependent on ionic strength and hardly dependent on pH over the observed pH range (6–13). The foreign cations competed with Cs(I) in the ...following order: K
+>Mg
2+>Ca
2+≈Na
+>Li
+. The uptake of Cs(I) was a pseudo-second-order process and the activation energy,
E
a
, was about 2.16
kJ/mol. EDS analysis suggested that the most of Cs(I) was converged on the basal plane, and a small fraction bound on the frayed sorption site. All the results suggested that ion exchange was the main approach for Cs(I) uptake on BS.
► Mineral composition and chemical component of Beishan soil were characterized firstly. ► Uptake kinetic process of Cs(I) on Beishan soil was investigated at different temperature. ► EDS technique was applied to study the uptake behaviors on Beishan soil surface.
Fibroblast growth factors (FGFs) play important roles in angiogenesis, wound healing, embryonic development, and endocrine signaling pathways. Increasingly, recent studies have reported aberrant FGF ...expression in various malignancies. However, the involvement of FGFs in cervical carcinoma pathogenesis remains unclear. We aimed to investigate expression of acidic (aFGF) and basic FGF (bFGF) in patients with this disease, and assess their effects on cervical cancer cell proliferation. Twenty cervical cancer patients and 10 cervical intraepithelial neoplasia (CIN) patients were recruited, and 10 cancer-free individuals were included as controls. Reverse transcription-polymerase chain reaction and western blotting were employed to detect FGF mRNA and protein levels, respectively. Furthermore, HeLa cells were treated with FGFs and subjected to thiazolyl blue tetrazolium bromide assays to quantify proliferation. Compared with CIN and normal cervical tissues, aFGF and bFGF mRNA and protein levels were significantly elevated in cervical carcinomas (P < 0.05). CIN tissues exhibited higher expression of these FGFs than normal tissues (P < 0.05). Moreover, their mRNA levels were increased in advanced cancer stages (P < 0.05), although no significant difference was detected between tumors of different differentiation grades in this regard (P > 0.05). HeLa cell proliferation increased in an aFGF- and bFGF-dose-dependent manner (P < 0.05), the latter exerting a more potent proliferative influence, with its effect peaking at 75 ng/mL. aFGF and bFGF were highly expressed in cervical cancer tissues and their levels positively correlated with clinical stage. Both facilitate proliferation of cervical carcinoma cells and are implicated in cancer pathogenesis and progression.
Prolonged delivery of neurotrophic proteins to the target tissue is valuable in the treatment of various disorders of the nervous system. We have tested in this study whether sustained release of ...nerve growth factor (NGF) within nerve guide conduits (NGCs), a device used to repair injured nerves, would augment peripheral nerve regeneration. NGF-containing polymeric microspheres fabricated from a biodegradable poly(phosphoester) (PPE) polymer were loaded into silicone or PPE conduits to provide for prolonged, site-specific delivery of NGF. The conduits were used to bridge a 10
mm gap in a rat sciatic nerve model. Three months after implantation, morphological analysis revealed higher values of fiber diameter, fiber population and fiber density and lower
G-ratio at the distal end of regenerated nerve cables collected from NGF microsphere-loaded silicone conduits, as compared with those from control conduits loaded with either saline alone, BSA microspheres, or NGF protein without microencapsulation. Beneficial effects on fiber diameter,
G-ratio and fiber density were also observed in the permeable PPE NGCs. Thus, the results confirm a long-term promoting effect of exogenous NGF on morphological regeneration of peripheral nerves. The tissue-engineering approach reported in this study of incorporation of a microsphere protein release system into NGCs holds potential for improved functional recovery in patients whose injured nerves are reconstructed by entubulation.
To evaluate the efficacy of aspiration in an opposite position to deal with pneumothorax after CT-guided lung biopsy.
A retrospective study was developed involving 210 patients with pneumothorax who ...had undergone CT-guided percutaneous core biopsies from January 2012 to March 2014 for various pulmonary lesions. Asymptomatic patients with minimal pneumothorax were treated conservatively. Simple manual aspiration was performed for symptomatic patients with minimal pneumothorax and for all patients with moderate to large pneumothorax. An opposite position aspiration was performed when simple manual aspiration failed. The efficacy of simple manual aspiration and the opposite position aspiration was observed.
Among 210 patients with pneumothorax, 128 (61.0%) asymptomatic patients with minimal pneumothorax were treated conservatively. The remaining 82 were treated with attempted simple manual aspiration. Out of these 82 patients, simple manual aspiration was successful in 58 (70.7%, 58/82) cases. The complete and partial regression rates were 17.2% (10/58) and 82.8% (48/58), respectively. In the other 24 patients (29.3%, 24/82), simple aspiration technique was ineffective. An opposite position (from prone to supine or vice versa) was applied, and a new biopsy puncture site was chosen for reaspiration. This procedure was successful in 22 patients but not in 2 patients who had to have a chest tube insertion. The complete and partial regression rates were 25.0% (6/24) and 66.7% (16/24), respectively. Applying the new method, the total effective rate of aspiration improved significantly from 70.7% (58/82) to 97.6% (80/82).
The opposite position aspiration can be safe, effective and minimally invasive treatment for CT-guided lung biopsy-induced pneumothorax thus reducing the use of chest tube significantly.
(1) Opposite position aspiration can elevate the success rate of aspiration significantly (from 70.7% to 97.6% in our study); (2) this procedure is a safe, effective and minimally invasive treatment for pneumothorax caused by biopsy; and (3) opposite position aspiration is a useful technique to reduce the use of chest tube, which has clinical significance.
PDF
