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1.
Appl Opt ; 58(27): 7523-7530, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674404

RESUMO

The fringe orientation is an important feature of the electronic speckle interferometry (ESPI) fringe pattern. Accurate and efficient calculation of the fringe orientation is very important for subsequent electronic speckle processing such as skeleton extraction and image filtering. To accurately and efficiently estimate fringe orientation, we propose an effective method based on a convolutional neural network. In the proposed method, the network needs clean-noisy image pairs to train and noisy images with theoretical value to test. The aligned noise-free ESPI fringe pattern orientation fields are fairly good estimations for the corresponding noise ones. After the model training is done, the other multiple ESPI fringe patterns are fed to the trained network simultaneously; the corresponding orientation results can be obtained accurately and efficiently. The advantage of using this method to extract the orientation is that the fringe orientation information can be extracted accurately and efficiently without complicated parameter adjustment. We evaluate the performance of our method via applying our method to the computer-simulated and experimentally acquired ESPI fringe patterns and comparing the results with those of three extensively used methods.

2.
Opt Express ; 27(22): 32378-32391, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684452

RESUMO

The fringe skeleton method is the most straightforward analysis method for phase extraction and widely used in dynamic measurement. Binarization is often required in this method. In the traditional binarization methods, filtering is often a necessary step prior to binarization due to the influence of intrinsic speckle noises in ESPI fringe patterns. In this paper, we propose a binarization method based on local entropy and fuzzy c-means (FCM) clustering algorithm. In this method, the pixels in the given ESPI fringe pattern are clustered into white fringes and black fringes according to their local entropy instead of the original intensity information. There is no need to perform the filtering preprocessing, because the intrinsic speckle noises are utilized as essentials. We evaluate the performance of our method by applying it to the computer-simulated and real fringe patterns. Experimental results demonstrate that the proposed method can achieve the desired binarization results, and the binarization results can give desired skeleton results.

3.
Opt Express ; 27(20): 28324-28336, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684586

RESUMO

In the nano-fabrication field, high precision displacement tracing of the fabricating beam is extensively required. Due to the coherence noise and the sensitivity to environmental disturbances, the commonly used measuring methods base on the laser interferometry are unstable. In this paper, a high-precision measuring method for the three-dimensional displacements is developed based on the low coherence interferometry. The interferogram at a particular location is unique and distinctive, which can be applied as a benchmark for the absolute measurement of positions. Consequently, interferograms are continuously acquired during the movement of the nano-stage, then the quantitative relationship between the stage position/tilt and the interferograms is established by analytic calculation. Besides, the influence of random errors can be suppressed by the averaging effect of the least squares fitting, thereby enhancing the precision by more than an order of magnitude compared with traditional methods. The measuring uncertainty is derived and the impacts of the main influencing factors are investigated. Experiments demonstrate that the measuring repeatability can achieve 1.16 nm. As a result, the proposed method can reliably obtain the absolute position and three dimensional trajectory of the nano-stage, and it is of significance to improve the reliability of nano-measurement and fabrication.

4.
Biol Lett ; 15(11): 20190447, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31690208

RESUMO

Natural and human disturbances have caused widespread regime shifts in shallow lakes of the lower Yangtze basin (LYB, China) resulting in a severe decline of ecosystem services. Improved understanding of the relationship between environmental forcing and ecosystem response, and the mechanisms behind regime shifts has significant implications for management. However, the patterns of these regime shifts and the underlying internal mechanisms are less known. In this study, two typical lakes (Chaohu and Zhangdu) from the LYB were selected to determine the trajectories of ecological regime shifts, both of which transitioned from vegetation- to plankton-dominated states several decades ago. Ecological trajectories since the 1900s in both lakes were reconstructed using palaeolimnological proxies, mainly diatom assemblages. Although results show that regime shifts occurred in both lakes in the 1970s and the 1950s, respectively, their inherent mechanisms were different. In Lake Zhangdu, altered hydrological conditions pushed the ecosystem across an ecological threshold, providing an example of a driver-mediated regime shift. In Lake Chaohu, ongoing nutrient loading influenced ecosystem processes and drove the lake to an alternative stable state, potentially presenting an example of a critical transition after a loss of resilience. This research indicates that palaeolimnological perspectives can provide insights into regime shift changes, as well as important information regarding which restoration methods should be tailored to individual lakes.

5.
Int J Psychophysiol ; 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31697960

RESUMO

Temporary self-construal (independent vs. interdependent) priming can modulate the neural response to the reward for an individual. Our previous event-related potential (ERP) studies have indicated that people experience the rewards for a friend less strongly than they experience the same amount rewards for themselves. However, an issue remaining unclear is whether the ERP responses to rewards for a friend vary according to the way in which the self is construed. In the present study, we manipulated participants' self-construal (independent vs. interdependent) and found that independent self-construal priming resulted in a greater feedback-related negativity (FRN) in response to outcome feedback for oneself than for a friend during a monetary gambling task. In contrast, interdependent self-construal priming resulted in a comparable FRN in response to outcome feedback for oneself and for a friend. The P3 amplitude was insensitive to the self-construal manipulation. Our findings suggest that interdependent priming may result in comparable motivation elicited by rewards for participants themselves and for their friends. This study provides novel evidence that the neural response to rewards for friend varies according to the way in which the self is construed.

6.
Hum Pathol ; 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31698008

RESUMO

The etiology and incidence of cirrhosis in adults has been well studied, however there is scant data in younger patients. The aim of this study was to determine causes of cirrhosis in patients ≤40years old. In this multi-institutional retrospective study, pathology databases were searched for patients ≤40-year-old with a diagnosis of cirrhosis from 1995 to 2018. Clinical charts and pathology reports were reviewed to identify etiologies of cirrhosis in each case. The patients were divided into 4 age groups (<1, 1-<5, 5-<18, and 18-40years old) for further analysis. We identified 594 patients (264 female, 330 male). Among <18-year-old patients, congenital cholestatic diseases and developmental disorders were the most common causes of cirrhosis (50.2%, 172/342). Metabolic and genetic diseases were also seen more commonly in this age group (16.6%, 57/342). In contrast, viral hepatitides were the most common cause of cirrhosis in 18-40-year-old patients (39.6%, 100/252) followed by autoimmune and fatty liver disease (22.2%, 56/252 and 15.07%, 38/252, respectively). Cryptogenic cirrhosis (overall 7.2%, 42/594) was seen in 3% (4/133), 1.4% (1/69), 10.7% (15/140) and 8.7% (22/252) of patients aged <1, 1-<5, 5-<18, and 18-40years, respectively. Developmental and metabolic disorders are the most common causes of cirrhosis in children (<18), while viral hepatitides are leading causes in adolescents and young adults (18-40) similar to adults. The incidence of cryptogenic cirrhosis also varies depending on the age, being lowest in 1-<5 year and highest in 5-<18 year age group children.

8.
World J Gastroenterol ; 25(39): 6025-6040, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31660038

RESUMO

BACKGROUND: Allicin (2-propene-1-sulfinothioic acid S-2-propenyl ester, diallyl thiosulfinate) extracted from garlic, has proven activity against Helicobacter pylori (H. Pylori) infection. In recent years, clinical trials have explored its utility as an add-on therapy with variable outcomes reported. AIM: To perform a systemic review of allicin as an add-on treatment for H. Pylori infection and assess its efficacy in randomized controlled trials (RCTs). METHODS: Electronic databases including MEDLINE, EMBASE, the Web of Science, the Cochrane Database, the China National Knowledge Infrastructure Database, Chinese VIP Information Databases, Chinese Medical Databases, and the Wan-Fang Database were searched for keywords including "allicin", "Helicobacter pylori", "randomized clinical trials", and their synonyms. A meta-analysis was performed using the fixed-effects model for low heterogeneity and the random-effects model for high heterogeneity with sensitivity analysis. Bias was evaluated using Egger's tests. Trial sequential analysis (TSA) was used to evaluate information size and treatment benefits. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) was used to assess the level of quality, and studies were classed as "high quality", "moderate quality", "low quality", and "very low quality". RESULTS: A total of eight RCTs consisting of 867 participants (435 from the allicin group and 432 from the control group) were included. Eradication rate in the allicin group (93.33%, 406/435) was significantly higher than that of the control group (83.56%, 361/432) [I 2 = 0%, odds ratio (OR) = 2.75, 95% confidence interval (CI): 1.74-4.35, P < 0.001]. The healing rate of ulcers following H. pylori therapy in the allicin group (86.17%, 349/405) was significantly higher than that of the control group (75.87%, 305/402) [I 2 = 0%, OR = 2.05, 95%CI: 1.39-3.03, P < 0.001]. The total remission rate of peptic ulcers across all allicin groups was 97.16%, which was significantly higher than that of controls [96.05% (389/405) vs 86.55% (360/402), I 2 = 0, OR = 3.04, 95%CI: 1.51-6.12, P = 0.015]. No significant differences in side effects were observed. TSA suggested that the trials were of sufficient standard to draw reliable conclusions. The quality of outcomes including eradication rates and side effects was graded as "very low" due to downgrades for "risk of bias" and "indirectness". Other outcomes such as ulcer healing rates and total ulcer remission rates were graded as "low" due to downgrades for "risk of bias". CONCLUSION: Allicin as an add-on therapy improves H. pylori eradication, healing of ulcers, and remission of symptoms. These results are suggested to be treated with caution due to limited quality.

9.
Chem Res Toxicol ; 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31664825

RESUMO

Artemisinin class of anticancer compounds is well-known for oxidative DNA damage-mediated growth arrest followed by cell death. However, the nature of this genotoxic stress for cancer therapeutics remains elusive. Here, we show that artesunate (Art), a water-soluble artemisinin analog, triggers inducible anticancer responses directly implicated in the DNA damage-intended therapy. We observed that the level of the antiviral enzyme APOBEC3C (apolipoprotein-B mRNA-editing catalytic polypeptide-like 3C, or A3C) preferentially increased upon treatment with Art against tumor xenografts of p53-deficitent H1299 cells. Using gain-of-function experiments, A3C could improve the therapeutic efficacy of Art determined by cell proliferation and colony formation assays. Furthermore, elevated A3C provoked a minor accumulation of γH2AX foci and phosphorylation of RPA32 and Chk1 which strongly sensitized H1299 cells to Art. Employment of A3C also caused increased the synergistic interaction between Art and Chk1 inhibition. Besides, A3C overexpression delayed cell cycle at S phase, accompanied by attenuated G2/M arrest in the presence of Art. Enzymatic inactivation of A3C by mutation of zinc-coordinating residues (C97S and C100S) indicated that A3C sensitized Art in a deaminase-dependent manner. Further, we showed using small interfering RNA against A3C can induce the chemoresistance of Art. These studies combine to suggest that upregulated A3C is involved in Art-induced DNA damage response as a consequent event to improve overall cytotoxic responses of Art.

10.
Br J Cancer ; 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31631174

RESUMO

BACKGROUND: Pancreatic cancer (PDAC) is a highly invasive cancer with poor prognosis. Recent research has found that the transcription factor Yin Yang 1 (YY1) plays an inhibitory role in the development of pancreatic cancer. It has been reported that tubulin polymerisation-promoting protein (TPPP) plays an indispensable role in a variety of tumours, but its expression and role in pancreatic cancer have not yet been elucidated. METHODS: In this study, we performed ChIP-sequencing and found that YY1 directly binds to the promoter region of TPPP. The expression of TPPP in pancreatic cancer was detected by western blotting and immunohistochemistry. Four-week-old male BALB/c-nude mice were used to assess the effect of TPPP on pancreatic cancer. RESULTS: Immunohistochemistry revealed that TPPP was expressed at low levels in pancreatic cancer tissues, and was associated with blood vessel invasion. The results from vivo experiments have showed that TPPP could enhance the migration and invasion of pancreatic cancer. Further experiments showed that YY1 could inhibit the migration, invasion and angiogenesis of pancreatic cancer cells by downregulating TPPP via p38/MAPK and PI3K/AKT pathways. CONCLUSION: Our study demonstrates that TPPP may act as a promoter and may serve as a novel target for the treatment of pancreatic cancer.

11.
Int J Cancer ; 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31633800

RESUMO

Colorectal cancer (CRC) is the third most common cancer and the second leading cause of cancer mortality worldwide. Emerging evidence indicates that tumour cells release substantial amounts of RNA into the bloodstream, in which RNA strongly resists RNases and is present at sufficient levels for quantitative analyses. This study aimed to discover blood-based markers for the early detection of CRC and to ascertain their efficiency in discriminating healthy controls, patients with polyps and adenomas and cancer patients. We first analysed and screened ZFAS1, SNHG11, LINC00909 and LINC00654 in a bioinformatics database and then collected clinical plasma samples for a preliminary small-scale analysis and further large-scale verification. We then explored the mechanism of dominant lncRNA SNHG11 expression in CRC by in vitro and in vivo assays. The combination of ZFAS1, SNHG11, LINC00909 and LINC00654 showed high diagnostic performance for CRC (AUC: 0.937), especially early-stage disease (AUC: 0.935). Plasma levels of the four candidate lncRNAs were significantly reduced in post-operative samples compared to pre-operative samples. A panel including these four lncRNAs performed well in distinguishing patient groups with different stages of colon disease, and SNHG11 exhibited the greatest diagnostic ability to identify precancerous lesions and early-stage tumour formation. Mechanistically, high SNHG11 expression promotes proliferation and metastasis by targeting the Hippo pathway. Taken together, the data indicate that SNHG11 may be a novel therapeutic target for the treatment of CRC and a potential biomarker for the early detection of CRC. This article is protected by copyright. All rights reserved.

12.
J Ethnopharmacol ; : 112310, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31629027

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: TianJiu (TJ) therapy, one type of cold moxibustion, applies to specific acupuncture points with herbal patches of hot nature, providing a constant irritant to the skin until the presence of hyperemia and blistering. Traditional and clinical reports suggest that TJ is an effective therapy for the treatment of jaundice with fresh Ranunculus sceleratus L. (RS), in which protoanemonin is one of the main irritant constituents. However, the therapeutic effect of TJ treatment with fresh RS against intrahepatic cholestasis has not been studied in animal experiments. AIM OF THE STUDY: Present study was undertaken to investigate the effect of TJ treatment with fresh RS against intrahepatic cholestasis in rats and provide an experimental basis for the underlying mechanism of TJ therapy. MATERIALS AND METHODS: Male intrahepatic cholestatic Sprague-Dawley rats induced by 2% α-naphthylisothiocyanate (ANIT, 80 mg/kg B.W.) were treated by TJ therapy with fresh RS. The levels of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), direct bilirubin (DBIL), total bilirubin (TBIL), total bile acid (TBA), hepatic malondialdehyde (MDA) and nitric monoxide (NO), as well as hepatic body ratio, bile flow and hepatic histopathological assay were measured and evaluated to investigate the therapeutic effect of TJ treatment with fresh RS. Phytochemical analysis of fresh and dried RS was performed by gas chromatography-mass spectrometer (GC-MS). RESULTS: After TJ treatment with fresh RS, the abnormally elevated levels of serum AST, ALT, ALP, DBIL, TBIL and TBA, as well as hepatic MDA and NO at 108 h were reduced significantly (versus model group, P < 0.01). The hepatic body ratio, bile flow and hepatic pathological change of cholestatic rats at 108 h in TJ group were restored when compared with those of model group. Thirty-one compounds including lactones, flavonoids and phenolic acids were identified and determined by GC-MS analysis. The content of protoanemonin in fresh RS (9.49%) was about 25-fold higher than that in dried RS (0.38%). CONCLUSIONS: TJ treatment with fresh RS exhibited good therapeutic effect on ANIT-induced intrahepatic cholestasis in rats, which may be due to the attenuated oxidative stress in the liver tissue. It is rational for the ancients to choose fresh RS as TJ herbal patches because of its abundant protoanemonin with the character of irritant. The qualitative and quantitative results of GC-MS analysis provided the chemical basis of TJ therapy with fresh RS, which can be regarded as a simple and efficient method for the treatment of cholestasis hepatitis.

13.
Future Oncol ; 15(32): 3723-3738, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31650850

RESUMO

Aim: Apocynum venetum polyphenol (AVP) was used in in vitro glioma cells culture to prove the growth inhibitory effect of AVP on human U87 glioma cells via NF-κB pathway. Materials & methods: The MTT assay, DAPI morphology, quantitative PCR and western blot experiments were used for determination in vitro. Results & conclusion: AVP can also induce U87 cancer cells apoptosis illustrated by DAPI morphology. AVP could enhance the mRNA and protein expression of IκB-α, TNF-α, TRAIL, caspase-3 and caspase-9 in U87 cancer cells and reduce those of NF-κBp65, cIAP-1, cIAP-2, TGF-ß2, CyclinD1, VEGF and IL-8. After ammonium pyrrolidine dithiocarbamate (PDTC) treatment, the NF-κBp65 expression was reduced in U87 cells, and AVP could raise these effects. The results of HPLC indicate that AVP mainly contains six constituents. The growth inhibitory effects of AVP on U87 glioma cells are predominantly from these natural active constituents.

14.
Platelets ; : 1-8, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31610686

RESUMO

Bleeding is the most common clinical symptom and the leading cause of death in patients with primary immune thrombocytopenia (ITP). Our research intends to verify the role of fibrinogen levels as independent determinants of bleeding. We retrospectively analyzed the relationship between fibrinogen levels and bleeding events in 463 patients. Additionally, we confirmed the impact of fibrinogen level on clot firmness in 25 patients via thrombelastography (TEG). Fibrinogen levels (median and inter-quartile range, IQR) were significantly different (p < .001) between bleeding and non-bleeding patients [258(207-314) mg/dL vs. 315(262-407) mg/dL, respectively]. Further analyzes in three subgroups based on platelet (PLT) count showed that non-bleeding patients still had higher fibrinogen levels than bleeding patients. The optimal discriminant threshold of fibrinogen in bleeding was 288.5 mg/dL according to receiver operating characteristic (ROC) curves. Patients were divided into low (LF, 230[193-258] mg/dL) and high (HF, 349[313-424] mg/dL) fibrinogen groups based on this threshold. Bleeding event rates were significantly different (LF: 84.6% vs. HF: 60.4%, P < .001) between the two groups. Multivariable analyses further confirmed these differences. Moreover, TEG parameters showed elevated clot firmness in the HF group. Our data suggest that high fibrinogen levels are associated with reduced bleeding events.

15.
Medicine (Baltimore) ; 98(39): e17151, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31574820

RESUMO

RATIONALE: Persistent primitive hypoglossal artery (PPHA) is often associated with intracranial anomalies such as aneurysms. Surgical treatment of aneurysms on the PPHA is challenging due to that the posterior circulation depends solely on PPHA. PATIENT CONCERNS: A case of an 83-year-old woman with a large aneurysm on PPHA presented with vertigo was reported. DIAGNOSIS: Three-dimensional angiogram revealed a wide-neck aneurysm on the PPHA. INTERVENTIONS: The aneurysm was successfully treated using a novel low-profile visualized intraluminal support stent-assisted coiling technique. OUTCOMES: No complications occurred during the procedure. The final angiogram confirmed the patency of the posterior inferior cerebellar artery and the parent artery and its distal branches. LESSONS: Our case suggests that stent-assisted coil embolization is safe and effective for the treatment of aneurysms on the PPHA.


Assuntos
Embolização Terapêutica/métodos , Aneurisma Intracraniano/cirurgia , Artéria Cerebral Posterior/cirurgia , Stents , Idoso de 80 Anos ou mais , Embolização Terapêutica/instrumentação , Feminino , Humanos , Resultado do Tratamento
16.
Medicine (Baltimore) ; 98(41): e17549, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31593136

RESUMO

BACKGROUND: The study aimed to evaluate and compare the dosimetric parameters of incidental irradiation to internal mammary node (IMN) from inverse intensity-modulated radiotherapy (I-IMRT) and field-in-field IMRT (F-IMRT), and 3-dimensional conformal radiotherapy (3D-CRT) in patients after breast-conservation surgery (BCS). METHODS: Eighty-four patients with BCS were selected. The breast, tumor bed, and IMN, including intercostal spaces (ICS) 1 to 3, were contoured. Three plans were generated. The prescription doses for the breast and tumor bed were 50.4 Gy/28 F and 60.2 Gy/28 F, respectively. If there was no tumor bed boost, patient was treated with 50 Gy/25 F for the whole breast only. The IMN was not included in planning target volume. RESULTS: The median mean dose (Dmean) of the IMNtotal (ICS 1-3) was 2740.2 cGy, 2973.9 cGy, and 2951.4 cGy for I-IMRT, F-IMRT, and 3D-CRT, respectively. Differences were not detected between any of the plans. After separating ICS 1 to 3 for further analysis, neither of the Dmean of ICS 1 to 2 was significantly different between the plans. However, for ICS 3, the median Dmean was highest for I-IMRT, and those for 3D-CRT and F-IMRT were not significantly different. After separating the 3 techniques for further analysis, the median Dmean was highest in ICS 3 and lowest in ICS 1 for all the 3 techniques. CONCLUSION: All 3 techniques failed to attain an adequate dose to cure subclinical disease, and there were no significant differences among the 3 techniques. It is risky to avoid IMN irradiation (IMNI) using any of the 3 techniques during whole-breast radiotherapy in women with indications for elective IMNI. However, in era of systematic therapy, whether the incidental dose could meet clinical acquirements needs further follow-up.


Assuntos
Mama/cirurgia , Radiometria/métodos , Radioterapia Conformacional/efeitos adversos , Radioterapia de Intensidade Modulada/efeitos adversos , Adulto , Idoso , Mama/patologia , Mama/efeitos da radiação , Feminino , Humanos , Linfonodos/patologia , Linfonodos/efeitos da radiação , Mastectomia Segmentar/métodos , Mediastino/patologia , Mediastino/efeitos da radiação , Pessoa de Meia-Idade , Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos , Parede Torácica/efeitos da radiação
17.
J Biomed Opt ; 24(10): 1-9, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31650743

RESUMO

A coaxial projective imaging (CPI) module acquires surgical scene images from the local site of surgery, transfers them wirelessly to the remote site, and projects instructive annotations to the surgical field. At the remote site, the surgical scene images are displayed, and the instructive annotations from a surgical specialist are wirelessly transferred back to the local site in order to guide the surgical intervention by a less experienced surgeon. The CPI module achieves seamless imaging of the surgical field and accurate projection of the instructive annotations, by a coaxial optical path design that couples the imaging arm with the projection arm and by a color correction algorithm that recovers the true color of the surgical scene. Our benchtop study of tele-guided intervention verifies that the proposed system has a positional accuracy of better than 1 mm at a working distance ranging from 300 to 500 mm. Our in vivo study of cricothyrotomy in a rabbit model proves the concept of tele-mentored surgical navigation. This is the first report of tele-guided surgery based on CPI. The proposed technique can be potentially used for surgical training and for telementored surgery in resource-limited settings.

18.
Wei Sheng Yan Jiu ; 48(4): 583-593, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31601339

RESUMO

OBJECTIVE: To understand the differences in the types and levels of antibiotic resistance genes contamination in the dust of air conditioning filters in hospital inpatient wards. METHODS: Wet cotton swabs were used to collect dust samples from air conditioning filters in 19 wards of 7 departments of a third-grade general hospital in Wuhan. The 24 antibiotic resistance genes related to 6 major antibiotics were qualitatively detected by PCR, and 6 typical resistance genes were detected by real-time PCR. RESULTS: Sulfonamides(sulI, sulII), ß-lactams(mecA, blaOXA-51, blaTEM, blaCTX-M, blaSHV, blaKPC, blaNDM-1, blaIMP, blaVIM), aminoglycosides(aac(6᾿-aph(2᾿, aacC2), macrolides(ermA, ermC, ereA), quinolones(qnrA, qnrB, qnrS), a total of five categories of 19 antibiotic resistance genes were detected in the dust of the filter. These include four carbapenem resistance genes(blaNDM-1, blaIMP, blaVIM, blaKPC). The average of absolute content(copies/g) of the six typical resistance genes from high to low was: sulI(1. 06×10~9)>sulII(1. 78×10~8)>blaNDM-1(3. 97×10~7)>aac(6᾿-aph(2᾿(3. 20×10~7)>blaTEM(1. 03×10~7)>aacC2(1. 13×10~6). Among the seven tested departments, traumatic surgery detected up to 18 resistant gene species and 6 typical genes with the highest absolute content. The absolute content of six typical genes in ICU and surgical wards was higher than medical wards. CONCLUSION: A variety of antibiotic resistance genes are detected in the dust of some hospital ward air conditioning filters, suggesting that there may be current or past pollution of resistant bacteria in the relevant environment.

19.
Org Lett ; 21(21): 8577-8581, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31613107

RESUMO

The known benzonaphthyridine alkaloid, albogrisin A (1), and six new compounds, including two pyrazinone stereoisomers, albogrisin B (2)/B' (2'), together with four 4H-pyrroloquinolinones, two diastereoisomers, albogrisin C (3)/C' (3'), and their methyl esters, albogrisin D (4)/D' (4'), were isolated from mangrove-derived Streptomyces albogriseolus MGR072. 2 and 2' are converted into 1 in acidic aqueous solution but into 3/3' and 4/4' in 0.05% trifluoroacetic acid acetonitrile. 4 and 4' are new indoleamine 2,3-dioxygenase 1 inhibitors.

20.
Colloids Surf B Biointerfaces ; 183: 110452, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31473409

RESUMO

Currently used Gd-based and Mn-based small molecular MRI contrast agents fail to meet the requirements for the long-term monitoring, and the potential safety risk under high administration dose or repeat dosing needs to be considered. In the present study, a biocompatible macromolecular magnetic resonance imaging (MRI) contrast agents based on O-carboxymethyl chitosan (CMCS), CMCS-(Mn-DTPA)n was designed and synthesized. The relaxivity of CMCS-(Mn-DTPA)n is approximately 3.5 and 5.5 times higher than that of Gd-DTPA and Mn-DPDP in aqueous solution, respectively. The MRI signal intensity in the kidney and liver of Sprague Dawley (SD) rats is significantly increased at a dose of 0.03 mM Mn/kg b.w. CMCS-(Mn-DTPA)n accompanied by a long effective imaging window. According to in vitro studies, CMCS-(Mn-DTPA)n exhibits good cellular and blood biocompatibility at the dose necessary for MRI imaging. Based on the results from in vivo studies, manganese (Mn) is completely excreted from SD rats within ten days after administration and does not exert a pathological effect on the liver. CMCS-(Mn-DTPA)n represents a potentially novel MRI contrast agent due to its excellent relaxivity, long effective imaging window and good biocompatibility.

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