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ABSTRACT A dual-plane resonant cell wideband bandpass filter is proposed and designed on substrate integrated waveguide (SIW) cavities using U-shape slots and H-shape fractal defected ground structure (DGS). The U-shape slots etched on the top meta layer of the SIW cavity are used to constitute a multiple-mode resonator and the H-shape fractal DGS etched on the bottom metal layer can greatly improve the filter performance while keeping the overall size of the filter circuit to be much compact. The proposed filter can lead to a size reduction of approximately one-third compared with the traditional SIW filters only using U-shape slots on the top metal plate of the SIW cavity. The filter has been fabricated and experimentally measured. The measured data are in good agreement with the simulated results. The measured 3 dB bandwidth is from 7.15 to 11.25 GHz, representing a fractional bandwidth of 44.6% at a center frequency of 9.2 GHz. Within the passband, the measured return loss performance is quite good (below −22dB), and the insertion loss is measured to be 1.05 dB, including the loss from two SMA connectors. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:111-114, 2016 [ABSTRACT FROM AUTHOR]

Mitochondrial malfunction and autophagy defects are often concurrent phenomena associated with neurodegeneration. We show that Miga, a mitochondrial outer-membrane protein that regulates endoplasmic reticulum-mitochondrial contact sites (ERMCSs), is required for autophagy. Loss of Miga results in an accumulation of autophagy markers and substrates, whereas PI3P and Syx17 levels are reduced. Further experiments indicated that the fusion between autophagosomes and lysosomes is defective in Miga mutants. Miga binds to Atg14 and Uvrag; concordantly, Miga overexpression results in Atg14 and Uvrag recruitment to mitochondria. The heightened PI3K activity induced by Miga requires Uvrag, whereas Miga-mediated stabilization of Syx17 is dependent on Atg14. Miga-regulated ERMCSs are critical for PI3P formation but are not essential for the stabilization of Syx17. In summary, we identify a mitochondrial protein that regulates autophagy by recruiting two alternative components of the PI3K complex present at the ERMCSs. [Display omitted] • Mitochondrial protein Miga regulates fusion between autophagosomes and lysosomes • Miga interacts with Atg14 to stabilize Syx17 • Miga interacted with Uvrag to regulate PI3K activity • Miga-induced ERMCSs are required for PI3K activity but not for Syx17 stabilization Miga is a mitochondrial outer-membrane protein that regulates endoplasmic reticulum-mitochondrial contact sites. Xu et al. show that Miga regulates autophagy by recruiting Atg14 and Uvrag, two alternative components of the PI3K complex. [ABSTRACT FROM AUTHOR]

Human telomeres are G-rich tandem repeats that assume G-quadruplex structures at the ends of chromosomes. Stabilization of telomeric G-quadruplex represents a significant drug target for inhibiting the telomerase activity that is required in about 85% of cancers. Metal ions have been revealed as important stabilizers to DNA G-quadruplexes, but their binding process with human telomeric G-quadruplex remains unclear. In this report, we show that K+ traverses into the G-tetrads centre of two G-tetrad layers through the half-capped top pathway constructed by the two edge-wise loop bases. The binding is mediated by the electrostatic interactions between K+ and the nearby bases of G-tetrads. However, direct traverse of K+ into the interior of G-quadruplex is negatively regulated by the steric hindrance of water molecules. Once K+ enters the G-quadruplex, stabilization of the in-plane or sandwiched conformation of the telomeric G-quadruplex-K+ complex is maintained by surrounding water molecules. These findings provide insights into the atomic interactions between K+ and telomere G-tetrads for targeted drug design. [ABSTRACT FROM AUTHOR]

Purposes: Routine smears of fine-needle aspiration (FNA) specimens of supraclavicular lymph nodes with ultrasound (US) real-time guidance have proven useful in lung cancer staging, but the clinical value of additional information from cell-block of FNA samples has been little researched. This study mainly focused on the contribution of cell block analysis to the diagnosis and staging in lung cancer.Materials and Methods: Clinical data about 211 lung cancer patients with supraclavicular lymph node enlargement admitted to ultrasonography in the Zhejiang Cancer Hospital and recommended a needle biopsy under US-guided, the adequacy of the specimens for preparing cell blocks was acquireded, and the additional immunohistochemistry or genetic information provided from cell block analysis was examined.Results: In 211 lung cancer patients referred for US-guided FNA (median age 61.8 ± 10.0 years, range 30-88) 279 aspirations were performed. Conventional smears could be obtained from 185 aspirates (66.3%) and contained 176 (95.1%) diagnostic smears. Cell blocks could be obtained from 94 aspirates (33.7%) and contained diagnostic material in 88 (93.6%) aspirates. Above all, cell blocks also made epithelial growth factor receptor gene mutation analysis in 17 patients with FNA samples, and the positive rate was 70.6%. Overall, cell blocks provided clinically significant information for 51 of the 211 patients participating in the study (24.2%).Conclusion: Cell-block samples from US-guided FNA is a promising, relatively noninvasive technique to provide additional information in lung cancer diagnosis. Analysis of cell blocks allows for genetic analysis of the patients with supraclavicular lymph nodes metastasis. [ABSTRACT FROM AUTHOR]

Telomere assumes intra-molecular G-quadruplex that is a significant drug target for inhibiting telomerase maintenance of telomeres in cancer. Metal cations have been recognized as playing important roles in stabilizing G-quadruplex, but their binding processes to human telomeric G-quadruplex remain uncharacterized. To investigate the detailed binding procedures, molecular dynamics simulations were conducted on the hybrid [3 + 1] form-one human telomeric intra-molecular G-quadruplex. We show here that the binding of a potassium ion to a G-tetrad core is mediated by two alternative pathways. Principal component analysis illustrated the dominant concerted motions of G-quadruplex occurred at the loop domains. MM-PBSA calculations revealed that binding was energetically favorable and driven by the electrostatic interactions. The lower binding site was found more constructive favorable for binding. Our data provide useful information on a potassium-mediated stable structure of human telomeric intra-molecular G-quadruplex, implicating in ion disorder associated conformational changes and targeted drug design. [ABSTRACT FROM AUTHOR]

The mini-review stemmed from a recent meeting on national aging research strategies in China discusses the components and challenges of aging research in China. Highlighted are the major efforts of a number of research teams, funding situations and outstanding examples of recent major research achievements. Finally, authors discuss potential targets and strategies of aging research in China. [ABSTRACT FROM AUTHOR]