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1.
Talanta ; 213: 120815, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32200920

RESUMO

Lead ions are deleterious pollutants that often reach drinking water, and can cause significant harm to humans (particularly children). An ultra-sensitive lead ion detection method using a whispering gallery mode (WGM) optofluidic microbubble resonator and the classic GR-5 DNAzyme is proposed in this paper. With the auxiliary piranha and Ploy-l-lysine solution, GR-5 DNAzyme was successfully modified on the inner wall of a microbubble. The mode field distribution of the microbubble was analysed, and the optofluidic sensor with thin wall exhibited a maximum bulk refractive index sensitivity of 265.2 nm/RIU. Lead ions at concentrations ranging from 0.1 pM to 100 pM were tested using the proposed WGM optofluidic sensor. The noise was decreased to 2.43 fM using the self-referenced differential method. Thus, a limit of approximately 15 fM was obtained for the detection of lead ions using the WGM optofluidic biosensor. Eight competing metal ions were also used to evaluate the selectivity of the proposed sensor, with results indicating that it has high selectivity for lead ions. Finally, the sensor performance is verified using real samples.

2.
Neurosci Lett ; 721: 134796, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32006627

RESUMO

Transcranial direct current stimulation (tDCS) is a form of brain stimulation technique that modulates neuronal excitability changes in targeted cerebral areas through a constant low current. The existing studies mainly concentrated in tDCS effects on motor cortex. The number of tDCS studies targeting visual area is sparse. And parameters of tDCS on the visual cortex are not well optimized yet. Therefore, this study explored the effect of anodal occipital tDCS in eyes-open resting state to disclose possible modulation to spontaneous brain activity by electroencephalography (EEG). Fifteen healthy subjects were involved in this study. Each subject endured sham and anodal tDCS in turn. 2 mA tDCS was applied over 21 min with Oz-Cz montage. Amplitudes of spontaneous brain activities were evaluated for each experimental condition. Compared with pre-stimulation and sham tDCS, anodal tDCS caused an obvious increment in parieto-occipital alpha activity. These results demonstrated electrophysiological changes in EEG oscillations induced by anodal occipital tDCS, and would help to improve the understanding of modulation of tDCS-induced visual cortex excitability changes in humans.

3.
J Biosci ; 452020.
Artigo em Inglês | MEDLINE | ID: mdl-32098919

RESUMO

The Homeobox B9 (HOXB9) is a homeodomain-containing transcription factor that participates in the progression of various malignancies. Nevertheless, the functional role of HOXB9 in prostate cancer cells is largely unknown. Hence, we aimed to address the effect of HOXB9 on the progression of prostate cancer cells. Small interfering RNA (siRNA) against HOXB9 was used to downregulate HOXB9 expression in PC3 and DU145 cells. Western blotting was performed to detect the expression levels of HOXB9 and other related proteins. Cell proliferation was tested by the Cell Counting Kit-8 (CCK-8) and cell cycle and apoptosis were investigated by flow cytometry. Angiogenesis was examined using tube formation assays The Transwell assays were carried out to assess the migratory and invasive capacities of cells. Here, we found that HOXB9 knockdown significantly reduced cell proliferation via inducing cell cycle arrest at G1 phase. This treatment also reduced angiogenesis, migration and invasion abilities of PC3 and DU145 cells in vitro. We also found that HOXB9 knockdown inhibits the activation of the PI3K/AKT signaling pathway in prostate cancer cells. In conclusion, our findings revealed that HOXB9 promotes prostate cancer progression and might be a novel and effective therapeutic target for human prostate cancer.

4.
J Am Chem Soc ; 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32053353

RESUMO

Topological defects, such as vortices and skyrmions, provide a wealth of splendid possibilities for new nanoscale devices because of their marvelous electronic, magnetic, and mechanical behaviors. Recently, great advances have been made in the study of the ferroelectric vortex in conventional perovskite oxides, such as BaTiO3 and BiFeO3. Despite extensive interest, however, no intriguing ferroelectric vortex structures have yet been found in organic-inorganic hybrid perovskites (OIHPs), which are desirable for their mechanical flexibility, ease of fabrication, and low acoustical impedance. We observed the robust vortex-antivortex topological configurations in a two-dimensional (2D) layered OIHP ferroelectric (4,4-DFPD)2PbI4 (4,4-DFPD is 4,4-difluoropiperidinium). This provides future directions for the study of perovskites and makes it a promising alternative for nanoscale ferroelectric devices in medical, micromechanical, and biomechanical applications.

5.
J Psychiatr Res ; 123: 136-144, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32065949

RESUMO

The human gut microbiome plays an important role in the basic neurodevelopmental processes of the central nervous system and has been implicated in several neuropsychiatric disorders. However, the connection between the gut microbiome and the underlying pathogenesis of schizophrenia (SCZ) is poorly defined. Here we analyzed the faecal samples from 40 first-episode drug-naïve SCZ (FSCZ) patients, 85 chronically antipsychotic-treated SCZ (TSCZ) patients and 69 healthy controls (HCs) using 16S rRNA gene sequence to determine whether the alterations of the gut microbiome were associated with SCZ or antipsychotic treatment. In addition, we acquired the T1-weighted brain imaging data by using structural magnetic resonance imaging to test whether microbial composition correlated with structural brain signatures. Our analyses revealed low microbiome alpha-diversity indexes in TSCZ patients but not in FSCZ patients as compared to HCs. Importantly, both FSCZ and TSCZ patients had distinct changes in gut microbial composition at certain taxa including Christensenellaceae, Enterobacteriaceae, Pasteurellaceae, Turicibacteraceae at the family level and Escherichia at genus level as compared to HCs. We also found significant disturbances of gut microbial composition in TSCZ versus FSCZ patients (eg. Enterococcaceae and Lactobacillaceae). Most interestingly, our exploratory analyses found specific SCZ-associated microbiota to be correlated with the right middle frontal gyrus (rMFG) volume which was aberrant in SCZ patients. Our findings extend prior work and suggest a possible link between the gut microbiome and brain structure which may be implicated in the pathology of SCZ.

6.
Schizophr Res ; 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31954611

RESUMO

The default mode network (DMN) has been consistently detected abnormally in schizophrenia. However, the effects of antipsychotics on this network are still under debate, and inconsistent findings may be due to the functional heterogeneity within the DMN, especially in the component regions of the posteromedial cortex (PMC). Here, we conducted a longitudinal research on the resting-state functional connectivity of the PMC subdivisions on 33 treatment-naive first-episode patients with schizophrenia at baseline and after 8 weeks of risperidone treatment through resting-state functional magnetic resonance imaging. At baseline, the patients demonstrated decreased connectivity of the three PMC seeds with several brain regions (target regions) compared with healthy controls. We then tested the effect of antipsychotic treatment on the functional connectivity between the three seeds and the target regions. We found that, one of the three seeds encompassed in PMC, namely, posterior cingulate cortex (PCC), was observed to have increased functional connectivity with the bilateral thalamus and the left lingual gyrus (LG). On the contrary, the functional connectivity between the target regions and the two remaining seeds, namely, the retrosplenial cortex and precuneus, was unaffected by risperidone treatment. Correlation analysis revealed a positive correlation between longitudinal change of PCC-LG connectivity and symptom improvement. These findings indicated the heterogeneity of the PMC in response to antipsychotic treatment and suggested the role of PCC as a treatment biomarker for schizophrenia.

7.
J Am Chem Soc ; 142(4): 1995-2000, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31913629

RESUMO

Molecular ferroelectrics are attracting tremendous interest because of their easy and environmentally friendly processing, light weight, low acoustical impedance, and mechanical flexibility, which are viable alternatives or supplements to conventional ceramic ferroelectrics. However, reports of ceramic-like molecular ferroelectrics that can be applied in the polycrystalline form have been scarce. Here, according to the "quasi-spherical theory", we successfully synthesized a ceramic-like molecular ferroelectric with an m3mFmm2 type phase transition at 357 K, 1,5-diazabicyclo[3.2.1]octonium tetrafluoroborate ([3.2.1-dabco]BF4), which can show excellent ferroelectric performance in the polycrystalline thin-film form at room temperature. On the basis of the reported molecular ferroelectric [2.2.2-dabco]BF4 (2.2.2-dabco = 1,4-diazabicyclo[2.2.2]octonium) with an Aizu notation of 4/mmmFmm2 and two polar axes, we changed the [2.2.2-dabco]+ cation to the [3.2.1-dabco]+ cation to reduce the molecular symmetry and keep the quasi-spherical shape simultaneously, making the number of polar axes up to six. Moreover, the spontaneous polarization Ps gets successfully increased from 4.9 µC cm-2 in [2.2.2-dabco]BF4 to 5.5 µC cm-2 in [3.2.1-dabco]BF4. This precise molecular design strategy offers an efficient pathway to design ceramic-like molecular ferroelectrics.

8.
Schizophr Res ; 215: 89-96, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31759811

RESUMO

Abnormal interactions between the striatum and salience network (SN) are considered as etiological and treatment-sensitive marker in schizophrenia. However, whether alterations in the intrinsic dynamics as reflected by resting-state functional connectivity (RSFC) between the striatum and salience network may predict treatment response to the widely used antipsychotic treatment strategies (risperidone, monotherapy) has not been examined systematically. To this end, treatment-naive first-episode schizophrenia patients (n = 41) underwent task-free resting-state fMRI assessment before (baseline) and after 8 weeks of risperidone monotherapy (n = 38). Intrinsic connectivity between striatal sub-regions and core salience processing nodes were examined and compared to carefully matched healthy controls (HC) to determine disorder-specific and treatment-predictive neural markers. Findings demonstrate hypo-connectivity of both ventral and dorsal striatal-SN pathways in patients at baseline. Importantly, specifically the dorsal striatal pathway at baseline could predict negative symptoms improvement in patients; while ventral striatal pathways could predict positive symptoms improvement. Together, results indicate that distinct striatal-SN pathways represent specific treatment-success markers for the effects of risperidone, suggesting that alterations in dorsal versus ventral striatal network markers may represent brain-based markers for specific symptomatologic improvements following risperidone mono-therapy.

9.
Angew Chem Int Ed Engl ; 59(9): 3495-3499, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-31828922

RESUMO

Molecular ferroelectrics have attracted considerable interests because of their easy and environmentally friendly processing, low acoustical impedance and mechanical flexibility. Herein, a molecular thermochromic ferroelectric, N,N'-dimethyl-1,4-diazoniabicyclo[2.2.2]octonium tetrachlorocuprate(II) ([DMe-DABCO]CuCl4 ) is reported, which shows both excellent ferroelectricity and intriguing thermochromism. [DMe-DABCO]CuCl4 undergoes a ferroelectric phase transition from Pca21 to Pbcm at a significantly high Curie temperature of 413 K, accompanied by a color change from yellow to red that is due to the remarkable deformation of [CuCl4 ]2- tetrahedron, where the ferroelectric and paraelectric phases correspond to yellow and red, respectively. Combined with multiple bistable physical properties, [DMe-DABCO]CuCl4 would be a promising candidate for next-generation smart devices, and should inspire further exploration of multifunctional molecular ferroelectrics.

10.
J Am Chem Soc ; 142(2): 1077-1082, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31851495

RESUMO

Piezoelectric sensors that can work under various conditions with superior performance are highly desirable with the arrival of the Internet of Things. For practical applications, a large piezoelectric voltage coefficient g and a high Curie temperature Tc are critical to the performance of piezoelectric sensors. Here, we report a two-dimensional perovskite ferroelectric (4-aminotetrahydropyran)2PbBr4 [(ATHP)2PbBr4] with a saturated polarization of 5.6 µC cm-2, high Tc of 503 K [above that of BaTiO3 (BTO, 393 K)], and extremely large g33 of 660.3 × 10-3 V m N-1 [much beyond that of Pb(Zr,Ti)O3 (PZT) ceramics (20 to 40 × 10-3 V m N-1), more than 2 times higher than that of poly(vinylidene fluoride) (PVDF, about 286.7 × 10-3 V m N-1)]. Combined with the advantages of molecular ferroelectrics, such as light weight, easy and environmentally friendly processing, and mechanical flexibility, (ATHP)2PbBr4 would be a competitive candidate for next-generation smart piezoelectric sensors in flexible devices, soft robotics, and biomedical devices.

11.
Schizophr Res ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31801675

RESUMO

Numerous studies strongly have suggested the significant role of serotonin in the pathomechanism of schizophrenia. However, few studies have directly explored the altered serotonin function in schizophrenia. In the current study, we explored the altered serotonin function in first-episode treatment-naive patients with schizophrenia with resting-state functional magnetic resonance imaging. A total 42 first-episode treatment-naive patients with schizophrenia and carefully matched healthy controls are included in the study. Considering that the raphe nucleus providing a substantial proportion of the serotonin innervation to the forebrain, the raphe nucleus was chosen as the seed to construct voxel-based functional connectivity (FC) maps. In the results, subcortical dopamine-related regions presented decreased FC with the raphe nucleus, such as the bilateral striatum, pallidum, and thalamus, in patients with schizophrenia. Decreased FC in these regions was significantly correlated with the total negative scores in PANSS. Furthermore, these regions presented with decreased FC connection to salience network. Our results presented that the raphe nucleus played an important role in the dysfunction of subcortical DA-related regions, and contributed to the altered salience network in schizophrenia. Our study emphasized the importance of the raphe nucleus in the pathophysiology of schizophrenia.

12.
Technol Cancer Res Treat ; 18: 1533033819886867, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31694481

RESUMO

OBJECTIVE: This study aimed to investigate the effect of circular RNA itchy E3 ubiquitin protein ligase on cell proliferation and apoptosis and to explore its target micro-RNAs in prostate cancer cells. METHODS: Circular RNA itchy E3 ubiquitin protein ligase expression in human prostate cancer cells and normal prostate epithelial cells was determined by real time-quantitative polymerase chain reaction assay. Circular RNA itchy E3 ubiquitin protein ligase overexpression plasmids (circular RNA itchy E3 ubiquitin protein ligase(+) group and control overexpression plasmids group were transfected with PC-3 cells. Rescue experiment was performed by transfection of circular RNA itchy E3 ubiquitin protein ligase overexpression and micro-197 overexpression plasmids (circular RNA itchy E3 ubiquitin protein ligase overexpression plasmids/micro RNA (+) group) into PC-3 cells. Cell Counting Kit-8 and annexin V/propidium iodide assays were conducted to evaluate cell proliferation and apoptosis, respectively. Western blot was performed to determine the expressions of apoptotic-related markers. RESULTS: Circular RNA itchy E3 ubiquitin protein ligase expression was decreased in DU 145, 22RV1, VCaP, and PC-3 cells compared to RWPE cells. In PC-3 cells, cell proliferation rate was reduced in circular RNA itchy E3 ubiquitin protein ligase overexpression plasmids group compared to control overexpression plasmids group at 48 hours and 72 hours. Cell apoptosis rate was elevated in circular RNA itchy E3 ubiquitin protein ligase overexpression plasmids group compared to control overexpression plasmids group at 48 hours, and Western blot showed the similar results. Micro RNA-197 but not micro RNA-31 or micro RNA-432 was the target micro-RNA of circular RNA itchy E3 ubiquitin protein ligase. In rescue experiments, cell proliferation rate was elevated, but apoptosis rate was reduced in circular RNA itchy E3 ubiquitin protein ligase overexpression plasmids/micro RNA (+) group compared to circular RNA itchy E3 ubiquitin protein ligase overexpression plasmids group, indicating that circular RNA itchy E3 ubiquitin protein ligase upregulation inhibited cell proliferation but promoted apoptosis through downregulating micro RNA-197. CONCLUSION: Circular RNA itchy E3 ubiquitin protein ligase upregulation suppresses cell proliferation but promotes apoptosis through targeting micro RNA-197 in prostate cancer. Our study may provide a new insight for the treatment of prostate cancer.

13.
Invest Ophthalmol Vis Sci ; 60(13): 4503-4510, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31661551

RESUMO

Purpose: MicroRNA-34a (miR-34a) has been implicated in many biological processes. It is downregulated in uveal melanoma, and introduction of miR-34a inhibits the proliferation and migration of uveal melanoma cells. Leucine-rich repeat-containing G protein-coupled receptor 4 (LGR4) is a novel target of miR-34a identified first in retinal pigment epithelial cells. In this study, we sought to evaluate the interaction of miR-34a and LGR4 in uveal melanoma and its downstream mechanisms. Methods: The expression of LGR4, epithelial-mesenchymal transition (EMT)-associated factors, and matrix metalloproteinase 2 (MMP2) in uveal melanoma cells was assessed by immunoblotting and immunofluorescence analysis. MicroRNA-34a mimic molecules, LGR4 small interfering RNA (siRNA), or MMP2-specific siRNA were transiently transfected into uveal melanoma cells. In vitro scratch and Transwell assays were used to evaluate the migratory and invasive potential of the resultant uveal melanoma cells. Results: LGR4 is upregulated in uveal melanoma cells. Introduction of miR-34a significantly decreased the expression level of LGR4. Transfection with miR-34a or knockdown of LGR4 attenuated the aggressiveness of uveal melanoma cells. In addition, there was a decrease in the expression of mesenchymal markers N-cadherin, vimentin, and Snail following miR-34a introduction or knockdown of LGR4. Finally, MMP2 was found to be a downstream effector for miR-34a and LGR4 that regulates the migration and invasion of uveal melanoma cells. Conclusions: MicroRNA-34a negatively controls LGR4, thereby inhibiting the migration and invasion of uveal melanoma cells. Ultimately, both miR-34a and LGR4 impact the aggressiveness of uveal melanoma with alterations in the markers of the EMT. MMP2 is a downstream effector that influences the metastasis seen with uveal melanoma cells.


Assuntos
Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Metaloproteinase 2 da Matriz/genética , Melanoma/genética , MicroRNAs/genética , Receptores Acoplados a Proteínas-G/genética , Neoplasias Uveais/genética , Movimento Celular/fisiologia , Proliferação de Células , Imunofluorescência , Humanos , Immunoblotting , Melanoma/patologia , RNA Interferente Pequeno , Transfecção , Células Tumorais Cultivadas , Regulação para Cima , Neoplasias Uveais/patologia
14.
J Am Chem Soc ; 141(45): 18334-18340, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31657909

RESUMO

Two-dimensional (2D) organic-inorganic perovskites (OIPs), with improved material stability over their 3D counterparts, are highly desirable for device applications. It is their considerable structural diversity that offers an unprecedented opportunity to engineer materials with fine-tuning functionalities. The isosteric substitution of hydrogen by an electronegative fluorine atom has been proposed as a useful route to improve the photovoltaic performance of 2D OIPs, whereas its valuable role in developing ferroelectricity is still waiting for further exploration. Herein, for the first time we applied fluorinated aromatic cations in extending the family of 2D OIP ferroelectrics, and successfully obtained [2-fluorobenzylammonium]2PbCl4 as a high-performance ferroelectric semiconductor. The failures in the nonferroelectric [4-fluorobenzylammonium]2PbCl4 and [3-fluorobenzylammonium]2PbCl4 demonstrate that the selective introduction of fluorine in correct structural positions is particularly essential. This work represents an unprecedented proof-of-concept in the use of fluorinated aromatic cations for the targeted design of excellent 2D OIP ferroelectrics, and is believed to inspire the future development of low-cost, high-efficiency, and stable device applications.

15.
Psychiatry Res ; 281: 112603, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31622873

RESUMO

The complex symptoms of schizophrenia (SCZ) have been associated with dysfunction of the default mode network (DMN). Subjects at genetic high risk (GHR) for SCZ exhibit similar but milder brain abnormalities. This study aimed to investigate functional alterations of DMN from the local to the whole and their relationships with cognitive deficits in GHR subjects. 42 GHR subjects and 38 matched healthy controls (HC) were studied by resting-state functional magnetic resonance imaging (rs-fMRI). Regional homogeneity (ReHo) analysis was performed to measure the local brain function of the DMN, derived by the group independent component analysis, and areas with aberrant ReHo were used as seeds in functional connectivity (FC). Compared with the HC group, the GHR group exhibited significantly decreased ReHo and increased FC in the fronto-limbic-striatal system within the DMN. Furthermore, a significant negative correlation was found between decreased ReHo in the right superior frontal gyrus and the delayed recall in GHR subjects. Our findings revealed decreased local function and hyper-connectivity in the fronto-limbic-striatal system of the DMN in GHR subjects, which is associated with cognitive deficits. This may improve our understanding of the neurophysiological endophenotypes of SCZ and the neural substrate underlying the cognitive deficits of the disease.

16.
Chem Asian J ; 14(21): 3863-3867, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31503382

RESUMO

Molecular optical-dielectric duple bistable switches are photoelectric (dielectric and fluorescent) multifunctional materials that can simultaneously convert optical and electrical signals in one device for seamless integration. However, exploring optical-dielectric duple channels of dielectric and photoluminescence is still a bigger challenge than single dielectric or photoluminescence bistable ones, which are hardly reported but probably will be heavily researched owing to the new generation artificial intelligence development needs in the future. Herein, a new optical-dielectric duple bistable switches material, [(CH3 )3 NCH2 CH3 ]2 MnCl4 (I), was obtained by a simple method for volatilization of solvents. Variable temperature single crystal X-ray analysis indicates that material I has a reversible bistable structure (order-disorder structure phase transition) corresponding to switching "ON'' and "OFF''. Unlike the single dielectric bistable structures that were previously reported, material I also own bistable features in terms of fluorescence property. This material enriches the specific examples of photoelectric duple function switch materials and facilitates the development of required devices.

17.
Schizophr Bull ; 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31504959

RESUMO

OBJECTIVE: The insula consists of functionally diverse subdivisions, and each division plays different roles in schizophrenia neuropathology. The current study aimed to investigate the abnormal patterns of dynamic functional connectivity (dFC) of insular subdivisions in schizophrenia and the effect of antipsychotics on these connections. METHODS: Longitudinal study of the dFC of insular subdivisions was conducted in 42 treatment-naive first-episode patients with schizophrenia at baseline and after 8 weeks of risperidone treatment based on resting-state functional magnetic resonance image (fMRI). RESULTS: At baseline, patients showed decreased dFC variance (less variable) between the insular subdivisions and the precuneus, supplementary motor area and temporal cortex, as well as increased dFC variance (more variable) between the insular subdivisions and parietal cortex, compared with healthy controls. After treatment, the dFC variance of the abnormal connections were normalized, which was accompanied by a significant improvement in positive symptoms. CONCLUSIONS: Our findings highlighted the abnormal patterns of fluctuating connectivity of insular subdivision circuits in schizophrenia and suggested that these abnormalities may be modified after antipsychotic treatment.

18.
BMC Vet Res ; 15(1): 272, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31370843

RESUMO

BACKGROUND: Ceftiofur Sodium is widely used in China. Our aim was to determine Ceftiofur Sodium activity and optimize dosing regimens against the pathogen Haemophilus parasuis using an in vitro and ex vivo pharmacokinetics/pharmacodynamics modeling approach. By adopting these strategies, we wanted to extend the effective life of Ceftiofur Sodium in reduce drug-resistance in pigs. RESULTS: We established an H. parasuis infection model in pigs, and assessed the pharmacokinetics of Ceftiofur Sodium in both healthy and infected animals. After Ceftiofur Sodium (10 mg/kg, i.m.) administration to healthy and H. parasuis-infected pigs, plasma based desfuroylceftiofur (a metabolite of Ceftiofur Sodium) was measured by High Performance Liquid Chromatography. The pharmacokinetics of Ceftiofur Sodium (desfuroylceftiofur) was consistent with a two-compartment open model, with first-order absorption. We observed no significant differences (P > 0.05) in pharmacokinetic parameters between healthy and infected pigs. Pharmacodynamics data showed that Ceftiofur Sodium was highly inhibitory against H. parasuis, with MIC, MBC, and MPC values of 0.003125, 0.0125 and 0.032 µg/mL, respectively. Desfuroylceftiofur in plasma also had strong bactericidal activity. Almost all H. parasuis cultured in plasma medium of Ceftiofur Sodium-inoculated healthy pigs, at each time point, were killed within 24 h. A weaker antibacterial activity was measured in infected-pig plasma medium at 18, 24, 36, and 48 h, after Ceftiofur Sodium inoculation. Pharmacokinetic parameters were combined with ex vivo pharmacodynamic parameters, and the bacteriostatic effect (36.006 h), bactericidal effect (71.637 h) and clearance (90.619 h) within 24 h, were determined using the Hill equation. Dose-calculation equations revealed the optimal dose of Ceftiofur Sodium to be 0.599-1.507 mg/kg. CONCLUSIONS: There were no significant differences in Ceftiofur Sodium pharmacokinetic parameters between healthy and infected pigs, although pharmacokinetics/pharmacodynamics fitting curves showed obviously differences. The optimal dose of Ceftiofur Sodium was lower than recommended (3 mg/kg), which may provide improved treatments for Glässers disease, with lower drug-resistance possibility.


Assuntos
Cefalosporinas , Infecções por Haemophilus/veterinária , Modelos Biológicos , Animais , Antibacterianos/farmacocinética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Cefalosporinas/farmacocinética , Cefalosporinas/farmacologia , Cefalosporinas/uso terapêutico , Infecções por Haemophilus/tratamento farmacológico , Infecções por Haemophilus/microbiologia , Haemophilus parasuis/efeitos dos fármacos , Suínos , Doenças dos Suínos/tratamento farmacológico , Doenças dos Suínos/microbiologia
19.
Chem Commun (Camb) ; 55(67): 10007-10010, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31373343

RESUMO

The significant Tc enhancement of 110 K in [N-fluoromethyldabconium] triiodide lead caused by the promising design of H/F substitution is the first and unprecedented, opening up an applicable and universal strategy to effectively regulate the Tc working temperature in phase transition materials.

20.
Dalton Trans ; 48(30): 11292-11297, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31268451

RESUMO

In this paper, three zero-dimensional organic-inorganic hybrid compounds [(CH3)3S]2[CdBr4] (1), [(CH3)3S]2[MnBr4] (2) and [(CH3)3S]2[ZnBr4] (3) were synthesized. The phase transition behavior of 1, 2 and 3 was well characterized by differential scanning calorimetry (DSC) and variable temperature single crystal diffraction measurements. The phase transition temperature of 1, 2 and 3 was at ca. 315 K in the heating process. The vigorous ordered-disordered reorientation and displacement motion of [(Me3)3S]+ and [MBr4]2- of 1, 2 and 3 induce the structural phase transition from the centrosymmetric (CS) space group Pnma to the non-centrosymmetric (NCS) space group P212121. The apparent second-harmonic generation (SHG) switching responses further confirm this CS to NCS symmetry breaking. Moreover, dielectric studies illustrate that 1, 2 and 3 display distinctly switchable dielectric behavior, revealing their potential application in dielectric switches. This finding suggests that sulfonium-based organic-inorganic hybrids can be used to build phase transition materials, broadening the way for exploring dielectric and nonlinear optical (NLO) switching materials.

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