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1.
Zhongguo Zhong Yao Za Zhi ; 45(4): 899-909, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32237492

RESUMO

Citri Reticulatae Pericarpium(CRP, Chinese name: Chenpi) is one of the most famous edible traditional Chinese medicines(TCMs). CRP was first recorded as top grade TCM in Shennong Bencao Jing attributing to the benefits such as regulating Qi, tonifying spleen, eliminating dampness and eliminating phlegm, and has been widely utilized for the treatments of abdominal fullness and distention, vomiting and diarrhea, as well as phlegm cough. CRP is also widely popular as spice in food industry. Because of the wide cultivation, a number of brands that exhibit extensive price range can be found in the market, resulting in a great challenge for grading. Herein, an attempt was made to in-depth chemome profiling for the sake of providing meaningful information of the universal quality control of CRP. A new core-shell column packed with adamantylethyl substituted silica gel particles was deployed for chromatographic separations and IT-TOF-MS that is advantageous at providing abundant high resolution molecular and fragment ions was employed for qualitative detection. A total of 62 components were observed and 61 ones were structurally annotated according to proposing mass fragmentation patterns, matching with reference compounds and relevant databases, and the chemical families included flavone, limonin, etc. In particular, ten compounds bearing 3-hydroxy-3-methylglutarate substitute were detected from CRP for the first time. Above all, the chemical profile of CRP was characterized and the findings are meaningful for the in-depth quality assessment and efficacy material clarification of CRP.

2.
Chemphyschem ; 21(9): 837-842, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32115829

RESUMO

Understanding of the fundamental mechanisms involved in the decomposition of 1,3,5-trinitro-1,3,5-triazinane (RDX) still represents a major challenge for the energetic materials and physical (organic) chemistry communities mainly because multiple competing dissociation channels are likely involved and previous detection methods of the products are not isomer selective. In this study we exploited a microsecond pulsed infrared laser to decompose thin RDX films at 5 K under mild conditions to limit the fragmentation channels. The subliming decomposition products during the temperature programed desorption phase are detected using isomer selective single photoionization time-of-flight mass spectrometry (PI-ReTOF-MS). This technique enables us to assign a product signal at m/z=42 to ketene (H2 CCO), but not to diazomethane (H2 CNN; 42 amu) as speculated previously. Electronic structure calculations support our experimental observations and unravel the decomposition mechanisms of RDX leading eventually to the elusive ketene (H2 CCO) via an exotic, four-membered ring intermediate. This study highlights the necessity to exploit isomer-selective detection schemes to probe the true decomposition products of nitramine-based energetic materials.

3.
Cancer Commun (Lond) ; 40(2-3): 93-104, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32175698

RESUMO

BACKGROUND: Human leukocyte antigen-identical sibling donor (ISD)-hematopoietic stem cell transplantation (SCT) is a potentially curative treatment for high-risk pediatric acute myeloid leukemia (AML). A haploidentical donor (HID) is readily available to almost all children. Previous studies have demonstrated that patients with HID-SCT had similar outcomes compared to ISD-SCT for pediatric and adult AML. However, the role of HID-SCT in high-risk pediatric AML is unclear. METHODS: To compare the overall survival of high-risk AML children who underwent either HID-SCT or ISD-SCT, we analyzed 179 cases of high-risk AML patients under 18 years of age treated with either ISD-SCT (n = 23) or HID-SCT (n = 156). Granulocyte colony-stimulating factor plus anti-thymocyte globulin-based regimens were used for HID-SCT. We also analyzed the subgroup data of AML patients at first complete remission (CR1) before SCT with known cytogenetic risk. RESULTS: The numbers of adverse cytogenetic risk recipients were 8 (34.8%) and 13 (18.8%) in the ISD-SCT group and the HID-SCT group, and the number of patients with disease status beyond CR1 were 6 (26.1%) and 14 (20.3%) in the two groups. The cumulative rates of grades II-IV acute graft-versus-host disease (GVHD) were 13.0% in the ISD-SCT group and 34.8% in the HID-SCT group (P = 0.062), with a three-year cumulative rates of chronic GVHD at 14.1% and 34.9%, respectively (P = 0.091). The relapse rate in the ISD-SCT group was significantly higher than that in the HID-SCT group (39.1% vs. 16.4%, P = 0.027); with non-relapse mortality at 0.0% and 10.6% (P = 0.113), respectively. The three-year overall survival rates were 73.0% for the ISD-SCT group and 74.6% for the HID-SCT group (P = 0.689). In subgroup analysis, the three-year relapse rate in the ISD-SCT group was higher than that in the HID-SCT group (50.0% vs. 9.2%, P = 0.001) and the three-year DFS in the ISD-SCT group (50.0%) was lower than that in the HID-SCT group (81.2%) (P = 0.021). CONCLUSIONS: Unmanipulated HID-SCT achieved DFS and OS outcomes comparable to those of ISD-SCT for high-risk pediatric AML patients with potentially higher rate but manageable GVHD.

4.
Emerg Microbes Infect ; 9(1): 457-468, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32090689

RESUMO

Porcine deltacoronavirus (PDCoV) is a newly emerging threat to the global porcine industry. PDCoV has been successfully isolated using various medium additives including trypsin, and although we know it is important for viral replication, the mechanism has not been fully elucidated. Here, we systematically investigated the role of trypsin in PDCoV replication including cell entry, cell-to-cell membrane fusion and virus release. Using pseudovirus entry assays, we demonstrated that PDCoV entry is not trypsin dependent. Furthermore, unlike porcine epidemic diarrhea virus (PEDV), in which trypsin is important for the release of virus from infected cells, PDCoV release was not affected by trypsin. We also demonstrated that trypsin promotes PDCoV replication by enhancing cell-to-cell membrane fusion. Most importantly, our study illustrates two distinct spreading patterns from infected cells to uninfected cells during PDCoV transmission, and the role of trypsin in PDCoV replication in cells with different virus spreading types. Overall, these results clarify that trypsin promotes PDCoV replication by mediating cell-to-cell fusion transmission but is not crucial for viral entry. This knowledge can potentially contribute to improvement of virus production efficiency in culture, not only for vaccine preparation but also to develop antiviral treatments.


Assuntos
Fusão Celular , Coronavirus/fisiologia , Fusão de Membrana , Tripsina/metabolismo , Animais , Linhagem Celular , Humanos , Suínos , Internalização do Vírus , Replicação Viral
5.
Viruses ; 12(1)2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31906441

RESUMO

The transcription factor NF-κB plays a critical role in diverse biological processes. The NF-κB pathway can be activated by incoming pathogens and then stimulates both innate and adaptive immunity. However, many viruses have evolved corresponding strategies to balance NF-κB activation to benefit their replication. Pseudorabies virus (PRV) is an economically important pathogen that belongs to the alphaherpesvirus group. There is little information about PRV infection and NF-κB regulation. This study demonstrates for the first time that the UL24 protein could abrogate tumor necrosis factor alpha (TNF-α)-mediated NF-κB activation. An overexpression assay indicated that UL24 inhibits this pathway at or downstream of P65. Furthermore, co-immunoprecipitation analysis demonstrated that UL24 selectively interacts with P65. We demonstrated that UL24 could significantly degrade P65 by the proteasome pathway. For the first time, PRV UL24 was shown to play an important role in NF-κB evasion during PRV infection. This study expands our understanding that PRV can utilize its encoded protein UL24 to evade NF-κB signaling.

6.
Cancer Med ; 9(1): 385-393, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31724329

RESUMO

Reproductive factors associated with breast cancer risk may also affect the prognosis. This study aimed to evaluate the associations of multiple reproductive factors with breast cancer prognosis and the modifying effects of menopausal status. We obtained data from 3805 breast cancer patients recruited between October 2008 and June 2016 in Guangzhou. The subjects were followed up until 30 June 2018. The hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated using multivariate Cox models to estimate the associations. It was found that there were U-shaped patterns for the associations of age at first birth and durations from first/last birth to diagnosis with breast cancer prognosis. The adverse effects of old age at first birth [>30 years vs 23-30 years, HR (95% CI): 1.59 (1.01-2.50)] and long intervals from first [≥20 years vs 10-19 years, HR (95% CI): 1.55 (1.07-2.27)] or last [≥20 years vs 10-19 years, HR (95% CI): 1.63 (1.08-2.46)] birth to diagnosis on progression-free survival (PFS) were significantly more pronounced among premenopausal women. Additionally, long interval (>5 years) between first and second birth was associated with a better PFS [HR (95% CI): 0.64 (0.42-0.97)]. These results suggested that age at first birth, durations from first/last birth to diagnosis, and intervals between first and second birth should be taken into account when following the patients and assessing the prognosis of breast cancer, particularly for premenopausal patients. These findings would also have implications for further insight into the mechanisms of breast cancer development.

7.
Food Chem ; 309: 125513, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31683147

RESUMO

The present study aims at synthesizing and in vitro antibacterial activity evaluation of chitosan oligosaccharide (COS) modified by Cinnamyl alcohol (Cin) onto the OH position of COS. Three different degrees of substitution (DS) COS-O-Cin1-3 were synthesized by changing different molar ratios of COS to Cin. UV-visible spectroscopy (UV-vis), Fourier transform infrared (FT-IR), 1H nuclear magnetic resonance (1H NMR), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and elemental analysis were conducted to characterize the successful synthesis of COS-O-Cin1-3. The results showed that they exhibited higher thermal stability, weaker crystallinity and better antibacterial properties than that of COS. These results aided in obtaining the important supports for exploring new functional antibacterial agents, which expand the scope of COS's application in the food industry.


Assuntos
Quitosana/química , Quitosana/farmacologia , Propanóis/química , Propanóis/farmacologia , Antibacterianos/análise , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Quitosana/análise , Quitosana/síntese química , Escherichia coli/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Propanóis/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Difração de Raios X
8.
Otol Neurotol ; 41(1): e132-e145, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31568136

RESUMO

OBJECTIVES: 1) To provide information on the treatment of pulsatile tinnitus (PT) with transtemporal extraluminal sigmoid sinus angioplasty (ESSA); and 2) to discuss the current clinical management of PT. STUDY DESIGN: This was a retrospective study. SETTINGS: Multi-institutional tertiary university medical centers. PATIENTS: Fifty-four PT patients with transverse-sigmoid sinus enlargement and prominent transverse-sigmoid junction with or without sigmoid sinus wall anomalies or transverse sinus anomalies. INTERVENTION: All patients underwent ESSA under local anesthesia. MAIN OUTCOME MEASURES: Intraoperative discoveries and surgical resolution of PT, morphology, and computational fluid dynamics. RESULTS: Fifty-three of the 54 (98%) patients experienced a significant reduction in, or complete resolution of, PT after ESSA. No major surgical complications occurred, except for one case where we observed a full collapse of the sinus wall. On average, this surgery reduced the cross-sectional area at the transverse-sigmoid junction by 61.5%. Our intraoperative discoveries suggest that sigmoid sinus wall anomalies may not be a definitive cause of PT. The transverse-sigmoid sinus system was significantly larger (in term of both cross-sectional area and volume) on the ipsilesional side compared with the contralesional side. Following ESSA, the vascular wall pressure and vortex flow at the transverse-sigmoid junction decreased considerably, and the flow velocity and wall shear stress increased significantly. CONCLUSION: ESSA is a highly effective surgical technique for PT patients with transverse-sigmoid sinus enlargement and prominent transverse-sigmoid junction, regardless of whether they also have sigmoid sinus wall or transverse sinus anomalies. A large transverse-sigmoid system with prominent transverse-sigmoid junction is a predisposing factor for PT, and only by improving patients' intrasinus hemodynamics could PT be resolved efficiently. In cases without complete obstruction of venous return, ESSA is safe. No postoperative complications related to neurological disorders were observed.

9.
Zhongguo Zhong Yao Za Zhi ; 44(21): 4720-4727, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31872670

RESUMO

An ultra-performance liquid chromatography hybrid triple quadrupole-linear ion trap mass spectrometry(UPLC-QtrapMS) method was established to identify the metabolites in rat plasma,bile,urine and feces after oral administration of Cinnamomi Cortex(CC) aqueous extract. Several survey experiments,such as enhanced mass spectrum scan(EMS),precursor ion scan(PI),neutral loss scan(NL) and multiple ions monitoring(MIM) were applied to search target components,and two separate enhanced product ion(EPI) scans were triggered via information-dependent acquisition(IDA) method to generate the MS/MS spectra. According to the mass spectrometric data collected from reference standards and reported literature,the structures of metabolites were deduced. A total of76 metabolites and 5 original compounds were tentatively identified in rats after oral administration of CC aqueous extract. Deglycosylation,methylation,sulfonation,and glucuronidation were observed as the primary metabolic pathways for the chemical constituents of CC. These data are able to benefit the clarification of the therapeutic material basis,the clinical usage and further R&D of CC.


Assuntos
Bile , Medicamentos de Ervas Chinesas/metabolismo , Espectrometria de Massas em Tandem , Administração Oral , Animais , Cromatografia Líquida de Alta Pressão , Fezes , Ratos
10.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 31(4): 410-413, 2019 Jul 29.
Artigo em Chinês | MEDLINE | ID: mdl-31612677

RESUMO

OBJECTIVE: To analyze the endemic sitaution of schistosomiasis based on geographic information system (GIS) in Wuhan City in 2017, so as to provide the reference for further schistosomiasis control activities. METHODS: According to the data of the annual report on the prevention and control of schistosomiasis in Wuhan City in 2017, the spatial database regarding the endemic situation of schistosomiasis was established and analyzed by ArcMap 10.2. RESULTS: The 593 schistosomiasis-endemic villages in Wuhan City were mainly located in the Yangtze River and its major tributaries. Kernel density analysis showed that the endemic villages of three regions with the highest density was located in the west of Caidian District (Zhuru Street), the east of Hannan District (Shamao Street) and the southwest corner of Xinzhou District (Yangluo Street). The sero-positive population was densely distributed in the West of Caidian District (Zhuru Street), which accounted for 34.23% of all seruo-positives in the city. There were 492 farming cattle fenced in Donggan Village in Hongbei Street of Caidian District. A higher density of the area with Oncomelania hupensis snails was located in the southwest region of Caidian District (Xiaosi Street), accounting for 31.22% of the total area with snails. In 2017, the re-emerging area with snails was 36.60 hm2. The high kernel density region with snails was located in Zhuru Street of Caidian District. The region with high density of living snails was located in the central region of Hannan District (Hongbei Production Brigade), the average density of living snails was 0.36 snails/0.1 m2. CONCLUSIONS: The endemic situation of schistosomiasis is at a low level in Wuhan City, and the spatial distribution is not uniform. In some local areas, the historical endemic situation of schistosomiasis is serious and the high risk factors are more concentrated. It is necessary to strengthen the surveillance of schistosomiasis.


Assuntos
Sistemas de Informação Geográfica , Esquistossomose , Animais , Anticorpos Anti-Helmínticos/sangue , China/epidemiologia , Doenças Endêmicas/estatística & dados numéricos , Humanos , Densidade Demográfica , Vigilância da População , Fatores de Risco , Esquistossomose/sangue , Esquistossomose/epidemiologia , Caramujos
11.
Neurosci Bull ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31502213

RESUMO

Scorpion venom heat-resistant peptide (SVHRP) is a component purified from Buthus martensii Karsch scorpion venom. Our previous studies have shown that SVHRP is neuroprotective in models of Alzheimer's disease and Parkinson's disease. The present study aimed to explore the potential neuroprotective effects of SVHRP on cerebral ischemia/reperfusion (I/R) injury, using a mouse model of middle cerebral artery occlusion/reperfusion (MCAO/R) and a cellular model of oxygen-glucose deprivation/reoxygenation (OGD/R). Our results showed that SVHRP treatment decreased the neurological deficit scores, edema formation, infarct volume and neuronal loss in the MCAO/R mice, and protected primary neurons against OGD/R insult. SVHRP pretreatment suppressed the alterations in protein levels of N-methyl-D-aspartate receptors (NMDARs) and phosphorylated p38 MAPK as well as some proinflammatory factors in both the animal and cellular models. These results suggest that SVHRP has neuroprotective effects against cerebral I/R injury, which might be associated with inhibition of the NMDA-MAPK-mediated excitotoxicity.

12.
Angew Chem Int Ed Engl ; 58(48): 17442-17450, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31482662

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) represent the link between resonance-stabilized free radicals and carbonaceous nanoparticles generated in incomplete combustion processes and in circumstellar envelopes of carbon rich asymptotic giant branch (AGB) stars. Although these PAHs resemble building blocks of complex carbonaceous nanostructures, their fundamental formation mechanisms have remained elusive. By exploring these reaction mechanisms of the phenyl radical with biphenyl/naphthalene theoretically and experimentally, we provide compelling evidence on a novel phenyl-addition/dehydrocyclization (PAC) pathway leading to prototype PAHs: triphenylene and fluoranthene. PAC operates efficiently at high temperatures leading through rapid molecular mass growth processes to complex aromatic structures, which are difficult to synthesize by traditional pathways such as hydrogen-abstraction/acetylene-addition. The elucidation of the fundamental reactions leading to PAHs is necessary to facilitate an understanding of the origin and evolution of the molecular universe and of carbon in our galaxy.

13.
J Ethnopharmacol ; 244: 112138, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31390529

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Dragon's blood (Chinese name: Xuejie), which comprises red resins obtained from several plants (27 species from 4 families), is drawing worldwide interests in medicinal applications owing to its broad pharmacological spectrum such as promoting blood circulation, regenerating muscle, relieving swelling and pain, maintaining hemostasis, etc. AIM OF THE STUDY: This work aims to evaluate current research progress on phenolic constituents, pharmacological activities, quality control, and metabolism of six Dracaena plants, namely, Dracaena cochinchinensis (Lour.) S.C.Chen, D. cambodiana Pierre ex Gagnep., D. cinnabari Balf. f., D. draco (L.) L., D. loureiroi Gagnep., and D. schizantha Baker, figure out the shortcomings of existing studies, and provide meaningful guidelines for future investigations. METHODS: Extensive database retrieval, such as SciFinder, PubMed, CNKI, ChemSpider, etc., was performed by using the keywords "Dracaena," "dragon's blood," as well as the Latin names of the six Dracaena species. In addition, relevant textbooks, patents, reviews, and documents were also employed to ensure sufficient information is collected. RESULTS: Flavonoids and their oligomers are the primary chemical clusters distributed in Dracaena plants. Pharmacological activities including analgesic, anti-inflammatory, antibacterial, hypolipidemic, hypoglycemic, and cytotoxic effects; bi-directional regulation effects on hemorheology; and cardiovascular and cerebrovascular effects have been disclosed by modern pharmacological evaluations. The chemical and metabolic profiles after oral administration of dragon's blood extract were preliminarily characterized. However, some of the pharmacological investigations reported only elementary methodologies and unreliable findings, and even worse, some important aspects were questionable or missing in these articles. CONCLUSIONS: Dragon's blood is a valuable source of bioactive compounds, mainly flavonoids and their oligomers. Its potential therapeutic effects on different diseases are attractive, such as the notable effect on cardiovascular diseases. In future studies, there is an urgent need to test the effect of this extract on appropriate cell lines and animal models to analyze its ethnopharmacological applications; moreover, "composition-effect correlation" methods and omics technologies are demanded for identifying the effective material basis and therapeutic mechanisms before entering into clinical trials. Moreover, attention should be paid to the chemical profiling and quality evaluation of this precious herbal medicine.

14.
Medicine (Baltimore) ; 98(32): e16693, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31393371

RESUMO

To strengthen rural health services, the Chinese government has launched a series of policies to promote health workforce development. This study aims to understand the current status of village doctors and to explore the factors associated with village doctors' job satisfaction in western China. It also attempts to provide references for further building capacities of village doctors and promoting the development of rural health service policy.A multistage stratified sampling method was used to obtain data from a cross-sectional survey on village doctors across 2 provinces of western China during 2012 to 2013. Quantitative data were collected from village doctors face-to-face, through a self-administered questionnaire.Among the 370 respondents, 225 (60.8%) aged 25 to 44 years, and 268 (72.4%) were covered by health insurance. Their income and working time calculated by workloads were higher than their self-report results. Being healthy, working fewer years, and having government funding and facilities were the positive factors toward their job satisfaction. Village doctors working with government-funded village clinics or facilities were more likely to feel satisfied.Problems identified previously such as low income and lack of insurance, heavy workload and aging were not detected in our study. Instead, village doctors were better-paid and better-covered by social insurance than other local rural residents, with increased job satisfaction. Government policies should pay more attention to improving the quality of rural health services and the income and security system of village doctors, to maintain and increase their job satisfaction and work enthusiasm. Further experimental study could evaluate effects of government input to improve rural health human resources and system development.


Assuntos
Satisfação no Emprego , Médicos/psicologia , Serviços de Saúde Rural/organização & administração , Adulto , Atitude do Pessoal de Saúde , Fortalecimento Institucional , China , Estudos Transversais , Humanos , Serviços de Saúde Rural/legislação & jurisprudência , Autorrelato
15.
Dalton Trans ; 48(35): 13472-13482, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31454007

RESUMO

Four chair-like hexanuclear Fe-Ln complexes containing mixed organic ligands, namely, [Fe4Ln2{(py)2CO2}4(pdm)2(NO3)2(H2O)2Cl4]·xCH3CN·yH2O (Ln = GdIII (1, x = 1, y = 0), DyIII (2, x = 1, y = 1), HoIII (3, x = 0, y = 2), and ErIII (4, x = 1, y = 3); (py)2CO2H2 = the gem-diol form of di-2-pyridyl ketone and pdmH2 = 2,6-pyridinedimethanol) have been obtained by employing di-2-pyridyl ketone and 2,6-pyridinedimethanol reacting with FeCl3 and Ln(NO3)3 in MeCN. The structures of 1-4 are similar to each other except for the number of lattice solvent molecules. Four FeIII and two LnIII in these complexes comprise a chair-like core with the "body" constructed by four FeIII ions and the "end" constructed by two LnIII ions. Among the four compounds, 2 shows field-induced single molecule magnet behavior as revealed by ac magnetic susceptibility studies, with the effective energy barrier and the pre-exponential factor of 22.07 K and 8.44 × 10-7 s, respectively. Ab initio calculations indicated that, among 2_Dy, 3_Ho and 4_Er fragments, the energy gap between the lowest two spin-orbit states for 2_Dy is the largest, while the tunneling gap for 2 is the smallest. These might be the reasons for complex 2 exhibiting SMM behavior. Additionally, the orientations of the magnetic anisotropy of DyIII in 2 were obtained by electrostatic calculations and ab initio calculations, both indicating that the directions of the main magnetic axis of Dy1 ions are almost aligned along Dy1-O5 (O5 from the pdm2- ligand).

16.
Talanta ; 205: 120119, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31450463

RESUMO

The authors describe a fluorescence polarization (FP) aptasensor based on the polymerase chain reaction (PCR) and streptavidin as dual FP amplifiers to detect chloramphenicol residues in food. Briefly, label-free aptamer was incubated with chloramphenicol and the aptamer-chloramphenicol conjugate was used as a template. Subsequently, the FAM-labeled forward primer and biotin-labeled reverse primer were added for PCR to amplify the template and the FAM-labeled primer. The molecular weight of FAM-labeled primer increased rapidly and the corresponding FP also enhanced. Finally, with the introduction of streptavidin, the PCR products and streptavidin were combined with the biotin-streptavidin interactions, resulting in much larger molecular weight. Thus, a dual amplified FP signal was obtained. Under optimal conditions, we were able to achieve a wide linear detection range of 0.001-200 nM. In addition, the designed strategy was applied to detect chloramphenicol in honey samples with high accuracy. Moreover, the strategy can be easily extended to detect other small molecules by changing the corresponding aptamers, which provide a promising avenue for the detection of small molecules by FP.

17.
J Clin Monit Comput ; 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31432382

RESUMO

Most surgical procedures involve structures deeper than the skin. However, the difference in surgical noxious stimulation between skin incision and laparoscopic trocar insertion is unknown. By analyzing instantaneous heart rate (IHR) calculated from the electrocardiogram, in particular the transient bradycardia in response to surgical stimuli, this study investigates surgical noxious stimuli arising from skin incision and laparoscopic trocar insertion, and their difference. Thirty-five patients undergoing laparoscopic cholecystectomy were enrolled in this prospective observational study. Sequential surgical steps including umbilical skin incision (11 mm), umbilical trocar insertion (11 mm), xiphoid skin incision (5 mm), xiphoid trocar insertion (5 mm), subcostal skin incision (3 mm), and subcostal trocar insertion (3 mm) were investigated. IHR was derived from electrocardiography and calculated by the modern time-varying power spectrum. Similar to the classical heart rate variability analysis, the time-varying low frequency power (tvLF), time-varying high frequency power (tvHF), and tvLF-to-tvHF ratio (tvLHR) were calculated. Prediction probability (PK) analysis and global pointwise F-test were used to compare the statistical performance between indices and the heart rate readings from the patient monitor. Analysis of IHR showed that surgical stimulus elicits a transient bradycardia, followed by the increase of heart rate. Transient bradycardia is more significant in trocar insertion than skin incision (p < 0.001 for tvHF). The IHR change quantifies differential responses to different surgical intensity. Serial PK analysis demonstrates de-sensitization in skin incision, but not in laparoscopic trocar insertion. Quantitative indices present the transient bradycardia introduced by noxious stimulation. The results indicate different effects between skin incision and trocar insertion.

18.
AMB Express ; 9(1): 112, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31332555

RESUMO

Cellulase has many potential applications in ethanol production, extraction of medicinal ingredients, food, brewing, oil exploration, environmental protection. However, the widespread use of cellulase is limited by its relatively high production costs and low biological activity. Therefore, we studied the enzymatic properties and reusability of cellulase immobilized on multiwalled carbon nanotubes and sodium alginate for the first time. The results showed that the optimum temperature and pH of immobilized cellulase was 40 °C and 3.0, respectively. After 1 month of storage at 4 °C, the enzyme activity of immobilized cellulase dropped to 71.2% of the baseline. Immobilized cellulase was proved to be reusable and maintained ~ 70% of its activity after 7 cycles of repeated use. Versus free cellulase, the immobilized cellulase showed good thermal stability, pH resistance, storage stability and reusability, which could be beneficial in large-scale industrial manufacturing processes.

19.
BMC Musculoskelet Disord ; 20(1): 321, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31288779

RESUMO

BACKGROUND: Pretension of the viscoelastic graft by cyclic knee motion has been confirmed to decrease the graft creep and improve the outcome of anterior cruciate ligament (ACL) reconstruction. The purpose of the present study was to investigate the effect of cyclic knee motion on the elongation of the four-strand hamstring tendon autograft in situ and to explore the stable level cycle, in which the tendon length achieved a stable level. METHODS: The study was performed with 53 consecutive patients undergoing transtibial ACL reconstruction with four strand hamstring tendon from Aug 2013 to Apr 2015. 43 males and 10 females were included with mean age of 29 ± 10 years. The pretension of the tendons was operated by cyclical knee motion ranging from 0 to 110°after the femoral fixation with Endo-button. The tendon length after 10, 20, 30 and 40 cycles was measured respectively and compared by repeated measure ANOVA. Then multivariate logistic regression was used to investigate the effect of the patients' parameters (age, gender, height, body weight, tendon length, etc.) on the elongation of the graft and the stable level cycle. RESULTS: The mean lengthening of the graft at 10, 20, 30 and 40 times was 3.0 ± 1.4 mm, 4.3 ± 1.5 mm, 4.8 ± 1.7 mm and 4.8 ± 1.8 mm respectively. No significant correlation was found between the elongation and the patients' parameters. There was significant difference of the tendon length from 0 to 30 cycles (F = 264.8, df = 1.95, p<0.001). However, the tendon length achieved a stable level after 30 cycles and the median elongation from 30 cycles to 40 cycles was 0 (0-1) mm with no significant difference (F = 2.039, p = 0.159). The male and female tendon length achieved to a stable level at 20 cycles and 30 cycles respectively but with no significant difference (p = 0.074). CONCLUSIONS: The four-strand hamstring tendon was elongated after cyclic knee motion and the elongation achieved a stable level after 30 cycles for the transtibial technique. Both of the tendon elongation and the stable level cycle were not correlated with patients' gender, age, preoperative duration, graft diameter and length.


Assuntos
Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/métodos , Artroscopia/métodos , Autoenxertos/fisiologia , Tendões dos Músculos Isquiotibiais/fisiologia , Adulto , Ligamento Cruzado Anterior/fisiopatologia , Ligamento Cruzado Anterior/transplante , Autoenxertos/transplante , Feminino , Tendões dos Músculos Isquiotibiais/transplante , Humanos , Período Intraoperatório , Articulação do Joelho/fisiopatologia , Articulação do Joelho/cirurgia , Masculino , Projetos Piloto , Amplitude de Movimento Articular/fisiologia , Transplante Autólogo/métodos , Resultado do Tratamento , Adulto Jovem
20.
Zhongguo Zhong Yao Za Zhi ; 44(13): 2667-2674, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31359675

RESUMO

Chemical profiling of a given herbal medicine( HM) is the prerequisite for clarifying the effective material basis and therapeutic mechanisms,and it is an important integral part of traditional Chinese medicine chemical biology( TCMCB). In current study,we aimed to propose a new strategy for fast chemical characterization of HM by using reversed phase liquid chromatography-hydrophilic interaction chromatography-predictive multiple reaction monitoring( RPLC-HILIC-p MRM),and Artemisiae Scopariae Herba was employed in this study to illustrate the entire strategy. In response to wide polarity spanning of the diverse chemical clusters in Artemisiae Scopariae Herba,RPLC and HILIC were coupled in series to retain and separate hydrophilic and hydrophobic components simultaneously by identifying the characteristics of chromatographic separation. Most of the chemical constituents in traditional Chinese medicine can be predicted by summarizing the results of chemical constituents of the same genera and introducing primary metabolites and possible substitution reaction types. Therefore,we constructed predictive ion pairs to rapidly identify the chemical constituents of Artemisiae Scopariae Herba. After comparison with control products,discussion on fragmentation pattern,and access to relevant information from literature and databases,a total of 139 components were detected and structurally annotated by matching the obtained spectral data with the information of authentic compounds. Above all,RPLC-HILIC-p MRM could be used as an eligible analytical tool for the chemical profiling of HMs.


Assuntos
Artemisia/química , Cromatografia de Fase Reversa , Plantas Medicinais/química , Interações Hidrofóbicas e Hidrofílicas , Medicina Tradicional Chinesa
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