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1.
Cancer Lett ; 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32044357

RESUMO

Colorectal cancer (CRC), a common malignancy, is among the leading causes of cancer-related deaths worldwide. Developing novel biomarkers is an important public health strategy to effectively reduce the mortality of this disease. Recent studies have found that exosomes may be important sources of biomarkers in CRC. Exosomes are nanometer-sized membrane vesicles (30-200 nm) secreted by normal or cancer cells, which participate in intercellular communication by transporting RNAs and proteins. Accumulating evidence has shown that some differentially expressed RNAs and proteins in exosomes play key roles in the initiation and development of CRC and are potential candidates for malignancy detection. Accordingly, exploring the correlation between these exosomes and CRC may be beneficial for the development of novel biomarkers in this disease. Here, we summarize the important roles of exosomes as biomarkers in CRC diagnosis, as well as the application in the metastasis, chemoresistance, and recrudescence of CRC. In particular, we discuss the prospects and limitations of exosomes as tumor markers.

2.
BMC Cancer ; 20(1): 32, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31931758

RESUMO

BACKGROUND: Vasculogenic mimicry (VM), defined as a capability of aggressive tumor Cells to mimic embryonic vasculogenic networks, caused poor prognosis in hepatocellular carcinoma (HCC). Rho kinases (ROCK), p21-activated kinase (PAK), hypoxia or epithelial-mesenchymal transition (EMT) contributed to the VM potential. However, the details underlying these biological behaviors have not been completely elucidated. METHODS: Kaplan-Meier analysis was conducted to predict relationship with hypoxia Inducible factor (HIF-1α), EMT related markers: Vimentin and patient prognosis. CD34/periodic acid-Schiff (PAS) double staining was examined to differentiate VM-positive (VM+) and VM-negative (VM-) samples. Cells were cultured under controlled hypoxic environments (1% O2) or normoxic conditions. The effect of hypoxia on RhoA/ROCK, Rac1/PAK and EMT were evaluated by real time-qPCR and western blot. HIF-1α small interfering RNA (siRNA), overexpressed or short hairpin RNA (shRNA) of ROCK and kinase inhibitors were used to explore the effect of HIF-1α, RhoA/ROCK, Rac1/PAK and Vimentin on VM. RESULTS: HIF-1α or Vimentin was upregulated in VM+ HCC tissues, compared to non-cancerous tissues (P < 0.01), and patients with high expression of HIF-1α or Vimentin had worse prognosis (P < 0.001). We showed hypoxia induced RhoA/ROCK and Rac1/PAK signaling transduction, and EMT could be repressed by HIF-1α siRNA. Notably, RhoA/ROCK or Rac1/PAK stabilized HIF-1α in hypoxia, whereas HIF-1α did not significantly altered RhoA/ROCK or Rac1/PAK signaling in hypoxia. Moreover, we found distinct roles of ROCK1, ROCK2 and PAK in regulating Vimentin phosphorylation. CONCLUSIONS: RhoA/ROCK and Rac/PAK signaling played crucial roles in hypoxia-induced VM via Ser72 and Ser56 Vimentin phosphorylation in HCC.

3.
Surg Obes Relat Dis ; 16(1): 1-9, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31679986

RESUMO

BACKGROUND: Obesity is associated with decreased brain gray- (GM) and white-matter (WM) volumes in regions. Laparoscopic sleeve gastrectomy (LSG) is an effective bariatric surgery associated with neuroplastic changes in patients with obesity at 1 month postLSG. OBJECTIVE: To investigate whether LSG can induce sustained neuroplastic recovery of brain structural abnormalities, and whether structural changes are accompanied by functional alterations. SETTING: University hospital, longitudinal study. METHODS: Structural magnetic resonance imaging and voxel-based morphometry analysis were employed to assess GM/WM volumes in 30 obese participants at preLSG and 1 and 3 months postLSG. One-way analysis of variance modeled time effects on GM/WM volumes, and then alterations in resting-state functional connectivity (RSFC) were assessed. RESULTS: Significant time effects on GM volumes were in caudate (F = 11.20), insula (INS; F = 10.11), posterior cingulate cortex (PCC; F = 13.32), and inferior frontal gyrus (F = 12.18), and on WM volumes in anterior cingulate cortex (F = 15.70), PCC (F = 15.56), and parahippocampus (F = 17.96, PFDR < .05). Post hoc tests showed significantly increased GM volumes in caudate (mean change ± SEM .018 ± .005 and P = .001, .031 ± .007 and P < .001), INS (.027 ± .008 and P = .003, .043 ± .009 and P < .001), and PCC (.008 ± .004 and P = .042, .026 ± .006 and P < .001), and increased WM volumes in anterior cingulate cortex (.029 ± .006 and P < .001, .041 ± .008 and P < .001), PCC (.017 ± .004 and P < .001, .032 ± .006 and P < .001), and parahippocampus (.031 ± .008 and P =.001, .075 ± .013 and P < .001) at 1 and 3 months postLSG compared with preLSG. Significant increases in GM volumes were in caudate (.013 ± .006 and P = .036), PCC (.019 ± .006 and P = .006), and inferior frontal gyrus (.019 ± .005 and P = .001), and in WM volumes in anterior cingulate cortex (.012 ± .005 and P = .028), PCC (.014 ± .006 and P = .017), and parahippocampus (.044 ± .014 and P = .003) at 3 relative to 1 month postLSG. GM volumes in INS and PCC showed a positive correlation at 1 (r = .57, P = .001) and 3 months postLSG (r = .55, P = .001). GM volume in INS and PCC were positively correlated with RSFC of INS-PCC (r = .40 and P = .03, r = .55 and P = .001) and PCC-INS (r = .37 and P = .046, r = .57 and P < .001) at 1 month postLSG. GM volume in INS was also positively correlated with RSFC of INS-PCC (r = .44, P = .014) and PCC-INS (r = .38, P = .037) at 3 months postLSG. CONCLUSION: LSG induces sustained structural brain changes, which might mediate long-term benefits of bariatric surgery in weight reduction. Associations between regional GM volume and RSFC suggest that LSG-induced structural changes contribute to RSFC changes.

4.
Knee ; 27(1): 9-17, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31864659

RESUMO

BACKGROUND: To evaluate the clinical outcomes of combined medial and lateral patellar retinaculum plasty for skeletally immature patients with patellar dislocation and low-grade trochlear dysplasia. METHODS: From December 2014 to December 2016, we reviewed 19 skeletally immature patients who underwent medial and lateral patellar retinaculum plasty at our institution. Clinical evaluations were performed pre- and postoperatively, and included determination of the number of patellar re-dislocation patients, the Kujala and Tegner scores, the patellar tilt angle, lateral patellar shift, and congruence angle. The radiographic evaluation parameters were measured on computed tomography scans. RESULTS: No dislocation or subluxation occurred during the mean follow-up of 35.42 months (24-48 months). Postoperatively, the Kujala score improved from 57.6 ±â€¯4.2 to 86.9 ±â€¯8.1 (P < 0.05), and the Tegner activity score improved from 2.6 ±â€¯1.0 to 5.0 ±â€¯1.3 (P < 0.05). Radiographically, the patellar tilt angle decreased from 32.7 ±â€¯5.9° to 13.4 ±â€¯4.28° (P < 0.05), the lateral patellar shift decreased from 15.9 ±â€¯1.1 mm to 8.4 ±â€¯0.6 mm (P < 0.05), and the congruence angle decreased from 29.9 ±â€¯15.3° to -9.6 ±â€¯15.5° (P < 0.05). CONCLUSIONS: Medial and lateral patellar retinaculum plasty is a promising procedure that has the advantage of being a simple operation that induces little trauma. It is a good treatment option for skeletally immature patients with patellar dislocation who have low-grade trochlear dysplasia.

5.
Clin Nucl Med ; 45(1): 90-91, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31789915

RESUMO

A 64-year-old woman with a history of cirrhosis and progressive difficulty breathing underwent pulmonary ventilation/perfusion SPECT to evaluate possible pulmonary embolism. The images demonstrated multiple mismatched ventilation/perfusion defects in both lungs, suggesting pulmonary embolism. However, there was also Tc-MAA radioactivity in the brain and bilateral kidney, with a right-to-left shunting rate of 8.8%. In addition, CT pulmonary angiography did not demonstrate embolus. The findings indicated that perfusion defects were caused by hepatopulmonary syndrome.

6.
Front Oncol ; 9: 1194, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31788451

RESUMO

Background: The present study aimed to compare the feasibility and safety of early oral feeding (EOF) with traditional oral feeding (TOF) after radical total gastrectomy for gastric cancer. Methods: This retrospective study included consecutive patients who underwent total gastrectomy from April 2016 and November 2018. These patients were divided into two groups, according to their postoperative feeding protocol: EOF group (n = 314) and TOF group (n = 433). Propensity score matching was used to balance the potential confounders, and 276 patients were selected from each group. The EOF group received oral diet on postoperative day one, while the TOF group were started on oral feeding after the passage of flatus. Results: No significant differences were found in the postoperative complications (P = 0.426) and tolerance to oral feeding (P > 0.056) between the two groups. The changes in perioperative nutritional markers were also similar between the two groups (P > 0.05). The time to first passage of flatus or defecation (47.19 ± 12.00 h vs. 58.19 ± 9.89 h, P < 0.0001) and length of postoperative hospital stay (6.84 ± 2.31 days vs. 7.72 ± 2.86 days, P < 0.0001) were significantly lower in the EOF group compared to the TOF group. Conclusion: EOF may be safe and feasible after radical total gastrectomy with faster recovery and no increased risk of postoperative complications.

7.
Ying Yong Sheng Tai Xue Bao ; 30(12): 4323-4332, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31840479

RESUMO

Soil microbes play essential roles in maintaining terrestrial ecosystem services. Soil moisture is a primary determinant of soil microbial activities and ecosystem functions, which may fluctuate dramatically with the altered precipitation patterns and extreme drought caused by the ongoing global climate change. Due to the distinct soil microbial tolerance and life-strategy approaches to drought stress and different water status, fluctuation of soil moisture has a direct impact on microbial activities and community structure, thereby profoundly affecting microbial-mediated processes and ecosystem functions. Thus, it is of great significance to understand the dynamics and mechanisms that underlie the microbial responses to soil water status. In this review, we summarized recent progress in the study of responses of soil microbial activities (e.g. soil respiration and enzyme activities) and community structure to soil water status. We summarized underlying microbial physiological and ecological mechanisms, particularly 1) the cellular physiological accommodation such as osmolyte accumulation, exopolysaccharide production and transition into dormant states, and 2) the ecological strategies such as stress-resistant gene transfer and functional redundancy. Therefore, this investigation on the underlying relationship between soil microbial assembly and ecosystem functions under different water status could further demonstrate the microbially-mediated soil biogeochemical processes and provide a theoretical basis for future research and modelling of terrestrial ecosystem responses to climate change.


Assuntos
Ecossistema , Solo , Bactérias , Mudança Climática , Microbiologia do Solo , Água
8.
Connect Tissue Res ; : 1-14, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31829044

RESUMO

Purpose: Trochlear dysplasia is one of the most frequent lower extremities deformities. Aim of this research was to investigate the changes in cartilage and subchondral bone of trochlea after patellar dislocation in growing rabbits. Materials and Methods: Ninety-six knees from 48 one-month-old rabbits were divided into two groups (experimental, control). Lateral patellar dislocation was established in the experimental group and distal femurs were collected at 4, 8, 12 and 24-week time points, respectively. General examination and histological observations were conducted to research the anatomical structure of the trochlear cartilage and subchondral bone. Structural parameters of trochlear subchondral bone were measured by MicroCT. Subsequently, the expression of TRPV4, collagen II and MMP-13 in cartilage were detected by western blot and RT-PCR analysis, respectively.Results: Subchondral bone loss was found in experimental group from 4 weeks after patellar dislocation, accompanied by increased TRAP-positive osteoclasts in subchondral bone. The trochlear dysplasia model was well established from 8 weeks after patellar dislocation. In addition, degeneration of cartilage was found from 8 weeks, accompanied by decreased expression of mechanically sensitive TRPV4 and collagen II, and increased expression of MMP-13.Conclusions: This study proved that trochlear dysplasia can be caused by patellar dislocation in growing rabbits, accompanied by significant subchondral bone loss. What is more, this study also shows that degenerative cartilage changes occur in the patellar dislocation model and become aggravated with time, accompanied by decreased TRPV4 and collagen II, but increased MMP-13.

9.
Opt Express ; 27(25): 36114-36128, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31873397

RESUMO

Single-photon detectors (SPDs) play important roles in highly sensitive detection applications, such as fluorescence spectroscopy, remote sensing and ranging, deep space optical communications, elementary particle detection, and quantum communications. However, the adverse conditions in space, such as the increased radiation flux and thermal vacuum, severely limit their noise performances, reliability, and lifetime. Herein, we present the example of spaceborne, low-noise, high reliability SPDs, based on commercial off-the-shelf (COTS) silicon avalanche photodiodes (APD). Based on the high noise-radiation sensitivity of silicon APD, we have developed special shielding structures, multistage cooling technologies, and configurable driver electronics that significantly improved the COTS APD reliability and mitigated the SPD noise-radiation sensitivity. This led to a reduction of the expected in-orbit radiation-induced dark count rate (DCR) increment rate from ∼219 counts per second (cps) per day to ∼0.76 cps/day. During a continuous period of continuous operations in orbit which spanned of 1029 days, the SPD DCR was maintained below 1000 cps, i.e., the actual in-orbit radiation-induced DCR increment rate was ∼0.54 cps/day, i.e., two orders of magnitude lower than those evoked by previous technologies, while its photon detection efficiency was > 45%. Our spaceborne, low-noise SPDs established a feasible satellite-based up-link quantum communication that was validated on the quantum experiment science satellite platform. Moreover, our SPDs open new windows of opportunities for space research and applications in deep-space optical communications, single-photon laser ranging, as well as for testing the fundamental principles of physics in space.

10.
Chin Med J (Engl) ; 132(23): 2835-2841, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31856055

RESUMO

BACKGROUND: There have been few reports of mutations in the beta-myosin heavy chain (MYH7) gene in hypertrophic cardiomyopathy (HCM), which is associated with sudden cardiac death caused by HCM. This study aimed to screen the mutation sites in the sarcomeric gene MYH7 in Chinese patients with HCM. We also planned to analyze the pathogenicity of the mutation site as well as its significance in clinical and forensic medicine. METHODS: From January 2006 to June 2017, autopsy cases were collected from the Department of Pathology, the Affiliated Hospital of Qingdao University. The experiment was to detect MYH7 gene status in formalin-fixed paraffin-embedded tissues from 18 independent autopsy cases who suffered HCM related sudden death (fatal HCM) and 20 cases without cardiomyopathy. Common mutation exon fragments of MYH7 gene were amplified by polymerase chain reaction. The end-of-deoxygenation method and gene cloning method were further performed to analyze the mutation sites. Homologous comparison among mutant sites was conducted using BLAST online database. RESULTS: The 1336th nucleotide of MYH7 gene at exon 14 was converted from T to G in one HCM case, resulting in the conversion of threonine (Thr) at position 446 to proline (Pro). In another case, the 1402th nucleotide at exon 14 was converted from T to C, resulting in the conversion of phenylalanine (Phe) at position 468 to leucine (Leu). Homologous comparison results showed that the two amino acid residues of Thr446 and Phe468 are highly conserved among different species. CONCLUSIONS: Our results showed fatal HCM harbored mutations of Thr446Pro and Phe468Leu in the MYH7 gene. It is significant for clinical and forensic medicine to further explore the functions and detailed mechanisms of these mutations.

11.
Opt Lett ; 44(21): 5262-5265, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674983

RESUMO

Polarization modulation plays a key role in polarization-encoding quantum key distribution (QKD). Here, we report a new, to the best of our knowledge, polarization modulation scheme based on an inherently stable Sagnac interferometer. The presented scheme is free of polarization mode dispersion and calibration as well as insensitive to environmental influences. Successful experiments at a repetition frequency of 1.25 GHz have been conducted to demonstrate the feasibility and stability of the scheme. The measured average quantum bit-error rate of the four polarization states is as low as 0.27% for 80 consecutive minutes without any adjustment. This high-speed intrinsically stable polarization modulation can be widely applied to many polarization-encoding QKD systems, such as BB84, MDI, etc.

12.
Front Oncol ; 9: 1096, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31696055

RESUMO

Background and Objective: Hepatocyte nuclear factor 3ß (HNF3ß) is a key transcription factor in the development of the gastrointestinal tract. However, only few studies have examined its' expression, function and potential clinical significance in colorectal cancer tumorigenesis and progression. Methods: HNF3ß expression in colorectal cancer tissue samples of 174 patients was assessed by immunohistochemistry. The results were analyzed with respect to patients' clinicopathological characteristics and survival. Following the in vitro cell transfection, MTT, wound healing, and Transwell assays were used to test cell proliferation, migration, and invasion, respectively. Western blot was used to examine IL6, JAK1, and STAT3 protein expression. The potential for tumor formation was evaluated using a mouse xenograft model. Results: HNF3ß expression was lower in colon cancer tissue compared to normal tissue and correlated with UICC clinical stage (P = 0.001), depth of invasion (P = 0.004), regional lymph node metastasis (P = 0.007), distant metastasis (P = 0.048), and poor survival (P < 0.001) in patients with colorectal cancer. Furthermore, HNF3ß overexpression impeded proliferation, migration and invasion of SW480 cells via JAK-STAT3 signaling in vitro. Moreso, HNF3ß overexpression showed a significant growth inhibition of subcutaneous xenograft tumors in vivo. Conclusions: The results show that HNF3ß acts as a suppressor of colorectal cancer progression and decreased HNF3 ß expression is closely related to the poor prognosis. Thus, HNF3ß may be a potential molecular target for inhibition of colorectal cancer cells and development of new anti-tumor therapies.

13.
Environ Sci Pollut Res Int ; 26(35): 36048-36054, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31745787

RESUMO

The essential oils (EOs) from aerial parts of Saussurea amara (L.) DC. (SAEO) and Sigesbeckia pubescens Makino (SPEO) were analyzed for their chemical composition by GC-MS, and their repellent activities against adults of the red flour beetle, Tribolium castaneum Herbst, as well as the booklouse, Liposcelis bostrychophila Badonnel, were evaluated for the first time. Results of GC-MS analysis indicated that both SAEO and SPEO were characterized by high content of sesquiterpenoids (relative content > 70%) including oxygenated sesquiterpenoids. The two oil samples and their major component caryophyllene oxide exerted beneficial repellent effects on T. castaneum and L. bostrychophila at 2 and 4 h post-exposure. At 4 h post-exposure, the PR value of caryophyllene oxide could still reach 92% (class V) against T. castaneum at minimum testing concentration of 3.15 nL/cm2, and this compound was observed to result in the greatest repellency (PR = 100%) against L. bostrychophila at 12.63 nL/cm2. This work confirmed the potent repellent efficacy of SAEO and SPEO for controlling pest damage and suggested their potential to be developed into botanical repellents.

14.
Kaohsiung J Med Sci ; 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31688991

RESUMO

MicroRNA-425-5p (miR-425-5p) has been reported to be involved in the tumorigenesis of several tumors, but its function in breast cancer is still unknown. In this study, miR-425-5p was found significantly upregulated in breast cancer cells, and predicted a poor prognosis for breast cancer patients. Overexpression of miR-425-5p could significantly promote breast cancer cell growth. Further studies showed that overexpression of miR-425-5p upregulated the protein levels of Cyclin D1, Cyclin D3, CDK4, and CDK6. However, inhibiting miR-425-5p downregulated their expression and induced cell cycle arrest at G0/G1 phase. In mechanism, overexpression of miR-425-5p increased the phosphorylation of PI3K p85 and AKT, but inhibiting miR-425-5p displayed opposite effects. Moreover, miR-425-5p bound to the 3'UTR of PTEN mRNA, and downregulated the expression levels of PTEN in both mRNA and protein levels in breast cancer cells. Collectively, the results above demonstrated that miR-425-5p was involved in the tumorigenesis of breast cancer by inducing PI3K/AKT signaling and indicated that miR-425-5p could be as a potential target for breast cancer therapy in the future.

15.
Science ; 366(6461): 132-135, 2019 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-31604316

RESUMO

Quantum mechanics and the general theory of relativity are two pillars of modern physics. However, a coherent unified framework of the two theories remains an open problem. Attempts to quantize general relativity have led to many rival models of quantum gravity, which, however, generally lack experimental foundations. We report a quantum optical experimental test of event formalism of quantum fields, a theory that attempts to present a coherent description of quantum fields in exotic spacetimes containing closed timelike curves and ordinary spacetime. We experimentally test a prediction of the theory with the quantum satellite Micius that a pair of time-energy-entangled particles probabilistically decorrelate passing through different regions of the gravitational potential of Earth. Our measurement results are consistent with the standard quantum theory and hence do not support the prediction of event formalism.

16.
Zhongguo Zhen Jiu ; 39(9): 918-22, 2019 Sep 12.
Artigo em Chinês | MEDLINE | ID: mdl-31544376

RESUMO

OBJECTIVE: To verify the effect of warm acupuncture combined with western medicine in patients with acute exacerbation chronic obstructive pulmonary disease (AECOPD) with phlegm-turbid obstructing of the lung. METHODS: Ninety patients with AECOPD were randomly divided into a western medicine group, a warm acupuncture group and a sham acupuncture group, 30 cases in each group. Routine treatment according to the Global initiative for chronic obstructive lung disease (GOLD) guidelines was used in the western medicine group. On the basis of the routine treatment, the warm acupuncture was applied at Fenglong (ST 40), Feishu (BL 13), Zusanli (ST 36) and other acupoints in the warm acupuncture group. In the sham acupuncture group, non-acupoints were taken on the basis of conventional treatment, and superficial acupuncture was performed for 1-3 mm, once a day for 2 weeks. Forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC, cough and sputum assessment questionnaire (CASA), COPD assessment test (CAT), and the change of TCM syndrome score were observed before and after treatment in all groups. RESULTS: After treatment, the FEV1, FVC and FEV1/FVC in each group were higher than those before treatment (P<0.05), there was no significant difference among groups after treatment (P>0.05). The CASA score, CAT score and TCM syndrome score in each group were lower than those before treatment (P<0.05). The change of the scores before and after treatment in the warm acupuncture group was higher than that in the sham acupuncture group and the western medicine group (P<0.05). There was no significant difference between the sham acupuncture group and the western medicine group (P>0.05). CONCLUSION: Warm acupuncture has a significant effect on the improvement of symptoms in patients with AECOPD with phlegm-turbid obstructing of the lung.


Assuntos
Terapia por Acupuntura , Doença Pulmonar Obstrutiva Crônica , Pontos de Acupuntura , Volume Expiratório Forçado , Humanos , Pulmão , Doença Pulmonar Obstrutiva Crônica/terapia
17.
J Org Chem ; 84(19): 12562-12572, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31539475

RESUMO

Chiral imidodiphosphoric acids were employed as efficient catalysts in the enantioselective addition reaction of pyrrole and indoles to 3-vinylindoles. A series of optically active 1,1,1-triarylethmanes bearing quaternary stereocenters were synthesized in excellent yields (up to 99% yield) and enantioselectivities (up to 98% ee). Gram-scale reactions of 1i and 2a as well as 1o and 5a demonstrated the synthetic utility of this methodology. Control experiments showed that the formation of a double H-bond between the catalyst and substrates is necessary for an excellent outcome.

18.
Small ; 15(44): e1903831, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31513340

RESUMO

In this study, a highly sensitive and self-driven near-infrared (NIR) light photodetector based on PdSe2 /pyramid Si heterojunction arrays, which are fabricated through simple selenization of predeposited Pd nanofilm on black Si, is demonstrated. The as-fabricated hybrid device exhibits excellent photoresponse performance in terms of a large on/off ratio of 1.6 × 105 , a responsivity of 456 mA W-1 , and a high specific detectivity of up to 9.97 × 1013 Jones under 980 nm illumination at zero bias. Such a relatively high sensitivity can be ascribed to the light trapping effect of the pyramid microstructure, which is confirmed by numerical modeling based on finite-difference time domain. On the other hand, thanks to the broad optical absorption properties of PdSe2 , the as-fabricated device also exhibits obvious sensitivity to other NIR illuminations with wavelengths of 1300, 1550, and 1650 nm, which is beyond the photoresponse range of Si-based devices. It is also found that the PdSe2 /pyramid Si heterojunction device can also function as an NIR light sensor, which can readily record both "tree" and "house" images produced by 980 and 1300 nm illumination, respectively.

19.
Chin Med J (Engl) ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31503054

RESUMO

BACKGROUND: There have been few reports of mutations in the beta-myosin heavy chain (MYH7) gene in hypertrophic cardiomyopathy (HCM), which is associated with sudden cardiac death caused by HCM. This study aimed to screen the mutation sites in the sarcomeric gene MYH7 in Chinese patients with HCM. We also planned to analyze the pathogenicity of the mutation site as well as its significance in clinical and forensic medicine. METHODS: From January 2006 to June 2017, autopsy cases were collected from the Department of Pathology, the Affiliated Hospital of Qingdao University, Qingdao Autopsy Center and Technical Department of Criminal Police Detachment of Qingdao Public Security Bureau. The experiment was to detect MYH7 gene status in formalin-fixed paraffin-embedded tissues from 18 independent autopsy cases who suffered HCM related sudden death (fatal HCM) and 20 cases without cardiomyopathy. Common mutation exon fragments of MYH7 gene were amplified by polymerase chain reaction. The end-of-deoxygenation method and gene cloning method were further performed to analyze the mutation sites. Homologous comparison among mutant sites was conducted using BLAST online database. RESULTS: The 1336th nucleotide of MYH7 gene at exon 14 was converted from T to G in one HCM case, resulting in the conversion of threonine (Thr) at position 446 to proline (Pro). In another case, the 1402th nucleotide at exon 14 was converted from T to C, resulting in the conversion of phenylalanine (Phe) at position 468 to leucine (Leu). Homologous comparison results showed that the two amino acid residues of Thr446 and Phe468 are highly conserved among different species. CONCLUSIONS: Our results showed fatal HCM harbored mutations of Thr446Pro and Phe468Leu in the MYH7 gene. It is significant for clinical and forensic medicine to further explore the functions and detailed mechanisms of these mutations.

20.
World J Clin Cases ; 7(13): 1582-1590, 2019 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-31367617

RESUMO

BACKGROUND: The central mechanism of idiopathic tinnitus is related to hyperactivity of cortical and subcortical auditory and non-auditory areas. Repetitive transcranial magnetic stimulation (rTMS) is a well-tolerated, non-invasive potential treatment option for tinnitus. AIM: To investigate the changes of neural metabolic activity after rTMS in chronic idiopathic tinnitus (IT) patients. METHODS: Eleven patients underwent rTMS (1 Hz, 90% motor threshold, 1000 stimuli/day for consecutive 10 d) on the left temporoparietal region cortex. Tinnitus handicap inventory (THI) and visual analogue score (VAS) were assessed at baseline and posttreatment. All patients underwent 18F-fluorodeoxyglucose (FDG) positron emission tomography to evaluate the neural metabolic activity. Data were preprocessed using statistical parametric mapping and Gretna software to extract the regions of interest (ROIs). The correlation between brain areas involved and THI scores was analyzed. RESULTS: Baseline and posttreatment parameters showed no significant difference regarding THI score (t = 1.019, P = 0.342 > 0.05) and VAS (t = 0.00, P = 1.0 > 0.05). Regions with the highest FDG uptake were the right inferior temporal gyrus (ITG), right parahippocampa gyrus (PHG), right hippocampus, rectus gyrus, left middle frontal gyrus, and right inferior frontal gyrus in IT patients. After rTMS treatment, IT patients showed increased activities in the right PHG, right superior temporal gyrus, right superior frontal gyrus, anterior insula, left inferior parietal lobule, and left precentral gyrus, and decreased activities in the left postcentral gyrus and left ITG. The ROIs in the right parahippocampa gyrus and right superior frontal gyrus were positively correlated with THI scores (r = 0.737, P = 0.037 < 0.05; r = 0.735, P = 0.038 < 0.05). CONCLUSION: Our study showed that 1-Hz rTMS directed to the left temporo-parietal junction resulted no statistically significant symptom alleviation. After treatment, brain areas of the limbic and prefrontal system showed high neutral metabolic activity. The auditory and non-auditory systems together will be the target for rTMS treatment.

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