779 research outputs found
Sequential cyclic changes of hair roots revealed by dermoscopy demonstrate a progressive mechanism of diffuse alopecia areata over time.
YesBACKGROUND: Diffuse alopecia areata (DAA) often leads to a complete hair shedding within a few months. OBJECTIVE: To explore features and mechanisms underlying DAA. MATERIALS AND METHODS: Scalp and hair root dermoscopy were conducted on 23 DAA patients throughout the disease process, 20 patchy Alopecia areata patients, 23 acute telogen effluvium (ATE) patients and 10 normal controls. Histopathology was also evaluated. RESULTS: We found almost all hair roots were anagen in early stage DAA in 18 patients (18/23, 78.3%) within the first 4-8 weeks after hair loss onset. Anagen effluvium (~4 weeks) was followed by catagen (~4 weeks) and then telogen/exogen (~8 weeks) effluvium with overlap. Hair root and proximal hair shaft depigmentation was more prominent in later DAA disease stages. Black dots, exclamation mark hairs and inconsistent thickness of hair shafts were found more often in early than later DAA (Ps < 0.01). Early DAA histopathology revealed more prominent inflammation and hair follicle regression than that observed in the later stages. Patchy alopecia areata patients showed mixed anagen, catagen and telogen hair roots while ATE patients showed increased exogen and mildly decreased hair root pigmentation. CONCLUSION: Sequential cyclic staging of shed hairs in DAA indicates the insult may be hair-cycle specific. We suggest that DAA is initially an anagen effluvium disease involving an intense inflammatory insult, later progressing to a brief catagen effluvium, and then to telogen effluvium with premature exogen, in later stages of DAA.This study was supported by the following grants to Xingqi Zhang: National Natural Science Foundation of China (81573066); Natural Science Foundation of Guangdong Province (2014A030313098)
Chemical and Biological Assessment of Angelica Roots from Different Cultivated Regions in a Chinese Herbal Decoction Danggui Buxue Tang
Roots of Angelica sinensis (Danggui) have been used in promoting blood circulation as herbal medicine for over 2000 years in China. Another species of Angelica roots called A. gigas is being used in Korea. To reveal the efficiency of different Angelica roots, the chemical and biological properties of Angelica roots from different cultivated regions were compared. Roots of A. sinensis contained higher levels of ferulic acid, Z-ligustilide, and senkyunolide A, while high amounts of butylphthalide and Z-butylenephthalide were found in A. gigas roots. The extracts deriving from A. gigas roots showed better effects in osteogenic and estrogenic properties than that of A. sinensis from China. However, this difference was markedly reduced when the Angelica roots were being prepared in a Chinese herbal decoction together with Astragali Radix as Danggui Buxue Tang. In contrast, the herbal decoction prepared from A. sinensis roots showed better responses in cell cultures. In addition, the extracts of A. gigas roots showed strong cell toxicity both as single herb and as Danggui Buxue Tang. This result revealed the distinct properties of Angelica roots from China and Korea suggesting the specific usage of herb in preparing a unique herbal decoction
Isorhamnetin, A Flavonol Aglycone from Ginkgo biloba L., Induces Neuronal Differentiation of Cultured PC12 Cells: Potentiating the Effect of Nerve Growth Factor
Flavonoids, a group of compounds mainly derived from vegetables and herbal medicines, share a chemical resemblance to estrogen, and indeed some of which have been used as estrogen substitutes. In searching for possible functions of flavonoids, the neuroprotective effect in brain could lead to novel treatment, or prevention, for neurodegenerative diseases. Here, different subclasses of flavonoids were analyzed for its inductive role in neurite outgrowth of cultured PC12 cells. Amongst the tested flavonoids, a flavonol aglycone, isorhamnetin that was isolated mainly from the leaves of Ginkgo biloba L. showed robust induction in the expression of neurofilament, a protein marker for neurite outgrowth, of cultured PC12 cells. Although isorhamnetin by itself did not show significant inductive effect on neurite outgrowth of cultured PC12 cells, the application of isorhamnetin potentiated the nerve growth factor- (NGF-)induced neurite outgrowth. In parallel, the expression of neurofilaments was markedly increased in the cotreatment of NGF and isorhamnetin in the cultures. The identification of these neurite-promoting flavonoids could be very useful in finding potential drugs, or food supplements, for treating various neurodegenerative diseases, including Alzheimer's disease and depression
Determination of Malachite Green in Aquaculture Water by Adsorptive Stripping Voltammetry
© 2016, Copyright © Taylor & Francis Group, LLC. An adsorptive stripping voltammetric method for the determination of malachite green in aquaculture water has been developed. Initial studies were made using the cyclic voltammetry of malachite green at a glassy carbon electrode in 0.1M phosphate buffer from pH 2 to 10. The redox behavior observed for malachite green was verified by the characterization of malachite green and its reduction product, leucomalachite green. Furthermore, leucomalachite green was found not to interfere with the determination of malachite green at pH 7.4, the optimum pH for malachite green determination. As a result, further studies were performed using adsorptive stripping voltammetry for the determination of malachite green in aquaculture water. The voltammetric waveform, accumulation potential, and accumulation time were optimized. The calibration plot was linear from 0.2µM to 1.2µM for malachite green using differential pulse voltammetry with a sensitivity of 0.8311µA/µM. Using the method of multiple standard addition, aquaculture water fortified with 0.5µM and 0.75µM malachite green provided mean recoveries of 78.79% and 87.20% with coefficients of variation of 2.07% and 1.45%. Therefore, analytical figures of merit suggest that this method provides rapid, simple, economical, and precise determination of malachite green in aquaculture water
The atomic gas of star-forming galaxies at z0.05 as revealed by the Five-hundred-meter Aperture Spherical Radio Telescope
We report new HI observations of four z0.05 star-forming galaxies
undertaken during the commissioning phase of the Five-hundred-meter Aperture
Spherical Radio Telescope (FAST). FAST is the largest single-dish telescope
with a 500 meter aperture and a 19-Beam receiver. Exploiting the unprecedented
sensitivity provided by FAST, we aim to study the atomic gas, via the HI 21cm
emission line, in low- star-forming galaxies taken from the Valpara\'iso
ALMA/APEX Line Emission Survey (VALES) project. Together with previous ALMA
CO() observations, the HI data provides crucial information to measure
the gas mass and dynamics. As a pilot HI survey, we targeted four local
star-forming galaxies at . In particular, one of them has already
been detected in HI by the Arecibo Legacy Fast ALFA survey (ALFALFA), allowing
a careful comparison. We use an ON-OFF observing approach that allowed us to
reach an rms of 0.7mJy/beam at a 1.7km/s velocity resolution within only 20
minutes ON-target integration time. We demonstrate the great capabilities of
the FAST 19-beam receiver for pushing the detectability of the HI emission line
of extra-galactic sources. The HI emission line detected by FAST shows good
consistency with the previous ALFALFA results. Our observations are put in
context with previous multi-wavelength data to reveal the physical properties
of these low- galaxies. We find that the CO() and HI emission line
profiles are similar. The dynamical mass estimated from the HI data is an order
of magnitude higher than the baryon mass and the dynamical mass derived from
the CO observations, implying that the mass probed by dynamics of HI is
dominated by the dark matter halo. In one case, a target shows an excess of
CO() in the line centre, which can be explained by an enhanced
CO() emission induced by a nuclear starburst showing high velocity
dispersion.Comment: 5 pages, 3 figures, 2 appendix, A&A Letter accepte
ALMA [N \i\i ] 205 \mu m Imaging Spectroscopy of the Lensed Submillimeter galaxy ID 141 at redshift 4.24
We present the Atacama Large Millimeter/submillimeter Array (ALMA)
observation of the Sub-millimeter galaxy (SMG) ID 141 at z=4.24 in the [N II]
205 m line (hereafter [N II]) and the underlying continuum at (rest-frame)
197.6 m. Benefiting from lensing magnification by a galaxy pair at
z=0.595, ID 141 is one of the brightest z SMGs. At the angular resolutions
of to ( kpc), our observation clearly
separates, and moderately resolves the two lensed images in both continuum and
line emission at . Our continuum-based lensing model implies an
averaged amplification factor of and reveals that the de-lensed
continuum image has the S\'ersic index and the S\'ersic radius of
kpc). Furthermore, the reconstructed [N II] velocity
field in the source plane is dominated by a rotation component with a maximum
velocity of km/s at large radii, indicating a dark matter halo mass
of . This, together with the reconstructed velocity
dispersion field being smooth and modest in value ( km/s) over much of
the outer parts of the galaxy, favours the interpretation of ID 141 being a
disk galaxy dynamically supported by rotation. The observed [N II]/CO (7-6) and
[N II]/[C II] 158 m line luminosity ratios, which are consistent with the
corresponding line ratio vs. far-infrared color correlation from local luminous
infrared galaxies, imply a de-lensed star formation rate of (/yr and provide an independent estimate on the size of
the star-forming region kpc in radius.Comment: 13 pages, 6 figures, 2 tables, accepted by ApJ, lensing model code
can be found here https://gitlab.com/cxylzlx/tiny_len
Chemical fingerprinting and quantitative analysis of two common Gleditsia sinensis fruits using HPLC-DAD
Gleditsiae Fructus Abnormalis and Gleditsiae Sinensis Fructus are obtained from different developmental stages of fruits from Gleditsia sinensis Lam. (Fam. Leguminosae). The possible interchangeable usage of the two fruits, however, has long been very controversial. Here, high performance liquid chromatography coupled with diode array detection was developed to explore their chemical fingerprinting profiles. Besides, the amounts of aglycons of saponin compounds, echinocystic acid and oleanolic acid in both fruits were quantified. The results indicated that there was no significant difference in the amount of aglycons from the two types of fruits; however, their chromatographic fingerprints showed distinct characteristics. Therefore, the interchangeable application of these fruits has to be taken with a specific precaution
Joint Inference in Weakly-Annotated Image Datasets via Dense Correspondence
We present a principled framework for inferring pixel labels in weakly-annotated image datasets. Most previous, example-based approaches to computer vision rely on a large corpus of densely labeled images. However, for large, modern image datasets, such labels are expensive to obtain and are often unavailable. We establish a large-scale graphical model spanning all labeled and unlabeled images, then solve it to infer pixel labels jointly for all images in the dataset while enforcing consistent annotations over similar visual patterns. This model requires significantly less labeled data and assists in resolving ambiguities by propagating inferred annotations from images with stronger local visual evidences to images with weaker local evidences. We apply our proposed framework to two computer vision problems, namely image annotation with semantic segmentation, and object discovery and co-segmentation (segmenting multiple images containing a common object). Extensive numerical evaluations and comparisons show that our method consistently outperforms the state-of-the-art in automatic annotation and semantic labeling, while requiring significantly less labeled data. In contrast to previous co-segmentation techniques, our method manages to discover and segment objects well even in the presence of substantial amounts of noise images (images not containing the common object), as typical for datasets collected from Internet search
Theoretical characterization of single-electron iodine-bond weak interactions in CH3…I-Y(Y = BH2, H, CH3, C2H3, C2H, CN, NC) systems
Inhibition of HIV virus by neutralizing Vhh attached to dual functional liposomes encapsulating dapivirine
Although highly active antiretroviral therapy (HAART) has greatly improved the life expectancy of HIV/AIDS patients, the treatment is not curative. It is a global challenge which fosters an urgent need to develop an effective drug or neutralizing antibody delivery approach for the prevention and treatment of this disease. Due to the low density of envelope spikes with restricted mobility present on the surface of HIV virus, which limit the antibody potency and allow virus mutation and escape from the immune system, it is important for a neutralizing antibody to form bivalent or multivalent bonds with the virus. Liposome constructs could fulfil this need due to the flexible mobility of the membrane with its attached antibodies and the capacity for drug encapsulation. In this study, we evaluated the neutralization activity of a range of liposome formulations in different sizes coated with anti-gp120 llama antibody fragments (Vhhs) conjugated via either non-covalent metal chelation or a covalent linkage. The non-covalent construct demonstrated identical binding affinity to HIV-1 envelope glycoprotein gp120 and neutralizing ability for HIV virus as free Vhh. Although covalently linked Vhh showed significant binding affinity to gp120, it unexpectedly had a lower neutralization potency. This may be due to the comparability in size of the viral and liposome particles restricting the number which can be bound to the liposome surface so involving only a fraction of the antibodies, whereas non-covalently attached antibodies dissociate from the surface after acting with gp120 and free the remainder to bind further viruses. Covalently conjugated Vhh might also trigger the cellular uptake of a liposome-virion complex. To explore the possible ability of the antibody-coated liposomes to have a further function, we encapsulated the hydrophobic antiviral drug dapivirine into both of the non-covalently and covalently conjugated liposome formulations, both of which revealed high efficacy in reducing viral replication in vitro. Thus, dual function liposomes may lead to a novel strategy for the prophylaxis of HIV/AIDS by combining the neutralizing activity of Vhh with antiviral effects of high drug concentrations
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