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1.
Molecules ; 29(12)2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38930813

RESUMO

Amidation of lactobionic acid with N,N-dimethylaminopropyltriamine was conducted to obtain N-(3'-dimethylaminopropyl)-lactamido-3-aminopropane (DDLPD), which was quaternized with bromoalkanes of different carbon chain lengths to synthesize double-stranded lactosylamide quaternary ammonium salt N-[N'[3-(lactosylamide)]propyl-N'-alkyl] propyl-N,N-dimethyl-N-alkylammonium bromide (CnDDLPB, n = 8, 10, 12, 14, 16). The surface activity and the adsorption and aggregation behaviors of the surfactants were investigated via equilibrium surface tension, dynamic light scattering, and cryo-electron microscopy measurements in an aqueous solution. The application properties of the products in terms of wettability, emulsification, foam properties, antistatic, salt resistance, and bacteriostatic properties were tested. CnDDLPB exhibited a low equilibrium surface tension of 27.82 mN/m. With an increase in the carbon chain length, the critical micellar concentration of CnDDLPBD decreased. Cryo-electron microscopy revealed that all products except C8DDLPB formed stable monolayer, multi-layer, and multi-compartmental vesicle structures in an aqueous solution. C14DDLPB has the best emulsification performance on soybean oil, with a time of 16.6 min; C14DDLPB has good wetting and spreading properties on polytetrafluoroethylene (PTFE) when the length of carbon chain is from 8 to 14, and the contact angle can be lowered to 33°~40°; CnDDLPB has low foam, which is typical of low-foaming products; C8DDLPB and C10DDLPB both show good antistatic properties. C8DDLPB and C14DDLPB have good salt resistance, and C12DDLPB has the best antimicrobial property, with the inhibition rate of 99.29% and 95.28% for E. coli and Gluconococcus aureus, respectively, at a concentration of 350 ppm.

2.
Langmuir ; 39(6): 2301-2311, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36719318

RESUMO

The potential of spider silk as an intriguing biological prototype for collecting water from a humid environment has attracted wide attention, and various materials with suitable structures have been engineered. Here, inspired by this phenomenon, a kind of superwetting poly(vinylidene fluoride) (PVDF) membrane with spindle-knotted structured fibers was prepared by the electrospinning method followed by oxygen plasma etching treatment. The prepared membrane presented a satisfactory separation efficiency for various oil-in-water emulsions. The cooperative effect of the special wettability property and the spindle-knot structure stimulated the emulsified oil droplets to accumulate quickly on the membrane surface. A model that explains the accumulation of emulsified oil droplets has also been developed. Furthermore, an artificial fiber comprising a micron-sized spindle-knot structure was prepared by the dip-coating method to clearly illustrate the aggregation process of the emulsified oil droplets and to verify the theoretical explanation. We hope that this study will provide new inspiration for oil/water emulsion separation techniques.

3.
AIDS Care ; 35(12): 1963-1970, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36919489

RESUMO

This study described the care status of People Living with HIV (PLWH) including antiretroviral therapy (ART) and viral suppression from 2018 to 2020. We recognized that immediate ART was associated with improved viral suppression. Therefore, we also aimed to explore the factors affecting the early initiation of ART. We initiated a retrospective cohort study to evaluate the care status of people living with HIV in Shandong Province. From 2018 to 2020, patients infected by homosexual transmission in particular had a higher ART rate (78.82%, 79.69%, and 87.72%, respectively). Of PLWH who received ART, 79.57%, 77.63%, and 67.71% achieved viral suppression, respectively. However, COVID-19 may affect the rate of ART and viral suppression, which we need to explore in our research. From 2018 to 2020, the proportion of immediate antiretroviral therapy within 30 days of diagnosis increased from 48.12% to 65.42%. Multivariate logistic regression demonstrated that patients with junior college degree or above (OR, 1.39 [95%CI, 1.12-1.73]) and key population or medical institutions (OR, 3.62 [95%CI, 2.18-6.16]; OR, 3.88 [95%CI, 2.33-6.59]) were substantially likely to receive ART immediately, while patients outside the province (OR, 0.60 [95%CI, 0.50-0.73]) were less likely to receive ART immediately.


Assuntos
Infecções por HIV , Humanos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Estudos Retrospectivos , Terapia Antirretroviral de Alta Atividade , China/epidemiologia , Homossexualidade
4.
BMC Gastroenterol ; 23(1): 369, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907841

RESUMO

BACKGROUND: The need for pain management is increasing in pediatrics, but the side effects of overuse or abuse of analgesics can be harmful to children's health and even life-threatening in severe cases. METHODS: Patients who underwent resection of Meckel's diverticulum at the Children's Hospital of Chongqing Medical University from July 1, 2019, to July 1, 2022, were included in this study. Opioids were administered through patient-controlled analgesia (PCA). Based on the preoperative choices made by the legal guardians, patients were stratified into two groups: PCA Group (PCAG) and Non-PCA Group (NPCAG). Data pertaining to the clinical characteristics and prognoses of these patients were subsequently collected and analyzed to assess the impact of opioid administration. RESULTS: In the study, a total of 126 patients were enrolled, with 72 allocated to the Patient-Controlled Analgesia Group (PCAG) and 54 to the Non-Patient-Controlled Analgesia Group (NPCAG). When compared to the NPCAG, the PCAG exhibited a longer duration of postoperative fasting (median 72 vs. 62 h, p = 0.044) and increased utilization of laxatives (12[16.7%] vs. 2[3.7%], p = 0.022). However, the PCAG also experienced higher incidences of intestinal stasis and abnormal intestinal dilation (13[18.1%] vs. 3[5.6%], p = 0.037). No statistically significant differences were observed in pain assessments at the conclusion of the surgical procedure (0 vs. 1[1.9%], p = 0.429) or within the first 24 h postoperatively (16[22.2%] vs. 18[33.3%], p = 0.164). Additionally, NPCAG patients did not necessitate increased administration of rescue analgesics (2[2.8%] vs. 4[7.4%], p = 0.432). CONCLUSIONS: The administration of opioids did not demonstrably ameliorate postoperative pain but was associated with a heightened incidence of postoperative gastrointestinal tract dysfunction. The retrospective nature of the current research should be considered and should be clarified further.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Gastroenteropatias , Humanos , Criança , Analgésicos Opioides/efeitos adversos , Estudos Retrospectivos , Analgésicos/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Gastroenteropatias/induzido quimicamente , Gastroenteropatias/cirurgia , Gastroenteropatias/tratamento farmacológico
5.
BMC Infect Dis ; 23(1): 496, 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37501181

RESUMO

BACKGROUD: The proportion of HIV-infected students in China showed an increasing trend. This study aimed to identify the epidemiological characteristics and the HIV care continuum for HIV-infected students in Shandong Province, China. METHODS: Case report and follow-up data of HIV-infected students were obtained from the National HIV/AIDS comprehensive response information management system. Logistic regression analyses were used to analyze the associating factors of HIV-infected students accepting CD4 + T cells (CD4) test and antiviral therapy (ART) in 30 days, and ArcGIS software was used for the spatial anlysis. RESULTS: From 2017 to 2019, 403 HIV-infected students were reported in Shandong Province. The majority of them were male (99.5%) and transmitted through homosexual sexual activity(92.1%). Most of them lived in Jinan city and Qingdao city. 68.5% (276 cases) accepted CD4 test in 30 days, and 48.6% (196 cases) started ART in 30 days. The heterosexual transmitted cases (AOR = 0.458, 95%CI: 0.210-0.998), patients accepting HIV care in western area (AOR = 0.266,95%CI: 0.147-0.481) were less likely to test CD4 within 30 days; patients aged 23-25 (AOR = 2.316, 95%CI: 1.009-5.316) and patients who had tested CD4 within 30 days (AOR = 4.377; 95%CI: 2.572-7.447) prefered to receive ART within 30 days; patients accepted HIV care in central area (AOR = 0.407; 95%CI: 0.251-0.657) and western area (AOR = 0.508; 95%CI: 0.261-0.989) and patients diagnosed by voluntary blood donation (AOR = 0.352; 95%CI: 0.144-0.864) were less willing to receive ART in 30 days. CONCLUSIONS: The HIV care continuum of HIV-infected students in Shandong Province still needed strenghthing. More health education and case management should be done for cases transmitted through heterosexual behavior, accepted HIV care in central and western area, and diagnosed by voluntary blood donation.


Assuntos
Infecções por HIV , Humanos , Masculino , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Estudos Retrospectivos , China/epidemiologia , Continuidade da Assistência ao Paciente , Estudantes
6.
J Med Internet Res ; 25: e49771, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38096014

RESUMO

BACKGROUND: The COVID-19 pandemic, caused by the SARS-CoV-2 virus, has necessitated reliable and authoritative information for public guidance. The World Health Organization (WHO) has been a primary source of such information, disseminating it through a question and answer format on its official website. Concurrently, ChatGPT 3.5 and 4.0, a deep learning-based natural language generation system, has shown potential in generating diverse text types based on user input. OBJECTIVE: This study evaluates the accuracy of COVID-19 information generated by ChatGPT 3.5 and 4.0, assessing its potential as a supplementary public information source during the pandemic. METHODS: We extracted 487 COVID-19-related questions from the WHO's official website and used ChatGPT 3.5 and 4.0 to generate corresponding answers. These generated answers were then compared against the official WHO responses for evaluation. Two clinical experts scored the generated answers on a scale of 0-5 across 4 dimensions-accuracy, comprehensiveness, relevance, and clarity-with higher scores indicating better performance in each dimension. The WHO responses served as the reference for this assessment. Additionally, we used the BERT (Bidirectional Encoder Representations from Transformers) model to generate similarity scores (0-1) between the generated and official answers, providing a dual validation mechanism. RESULTS: The mean (SD) scores for ChatGPT 3.5-generated answers were 3.47 (0.725) for accuracy, 3.89 (0.719) for comprehensiveness, 4.09 (0.787) for relevance, and 3.49 (0.809) for clarity. For ChatGPT 4.0, the mean (SD) scores were 4.15 (0.780), 4.47 (0.641), 4.56 (0.600), and 4.09 (0.698), respectively. All differences were statistically significant (P<.001), with ChatGPT 4.0 outperforming ChatGPT 3.5. The BERT model verification showed mean (SD) similarity scores of 0.83 (0.07) for ChatGPT 3.5 and 0.85 (0.07) for ChatGPT 4.0 compared with the official WHO answers. CONCLUSIONS: ChatGPT 3.5 and 4.0 can generate accurate and relevant COVID-19 information to a certain extent. However, compared with official WHO responses, gaps and deficiencies exist. Thus, users of ChatGPT 3.5 and 4.0 should also reference other reliable information sources to mitigate potential misinformation risks. Notably, ChatGPT 4.0 outperformed ChatGPT 3.5 across all evaluated dimensions, a finding corroborated by BERT model validation.


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Pandemias , Idioma , Organização Mundial da Saúde
7.
Molecules ; 28(20)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37894630

RESUMO

This paper reports the synthesis of a novel quaternary surfactant containing a hydroxyethyl group (PFPE-C) and the surface properties of its aqueous solution (investigated by comparisons with two structurally similar chemicals, dodecyl-(2-hydroxyethyl)-dimethylammonium chloride (DHDAC) and PFPE-A). The minimum surface tension (γCMC) and critical micelle concentration (CMC) of the PFPE-C aqueous solution were 17.35 mN/m and 0.024 mmol/L, respectively. This study confirms that surfactants containing hydroxyethyl groups efficiently reduce the surface tension of aqueous solutions, and fluorocarbon surfactants exhibit better surface activity than ordinary hydrocarbon surfactants with similar structures. The micellization, aggregation, air-water interfacial adsorption, and wettability of PFPE-C aqueous solutions have been systematically investigated. Highly concentrated PFPE-C aqueous solutions exhibit good wettability on PTFE and paraffin films. Moreover, the aggregates of PFPE-C in the aqueous solution were clearly seen as vesicles on Cryo-TEM micrographs. Primary biodegradation results indicate that 19% of PFPC-C can be degraded within one week.

8.
Nanotechnology ; 33(24)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35245907

RESUMO

Black phosphorus (BP) exhibits great potential as antibacterial materials due to its unique photocatalytic activity. However, the unsatisfactory optical absorption and quick recombination of photoinduced electron-hole pairs restrain its photocatalytic antibacterial performance. In this work, silver nanoparticles (AgNPs) were decorated on BP to construct BP@AgNPs nanohybrids and then introduced into poly-l-lactic acid scaffold. Combining the tunable bandgap of BP and the LSPR effect of AgNPs, BP@AgNPs nanohybrids displayed the broaden visible light absorption. Furthermore, AgNPs acted as electron acceptors could accelerate charge transfer and suppress electron-hole recombination. Therefore, BP@AgNPs nanohybrids achieved synergistically enhanced photocatalytic antibacterial activity under visible light irradiation. Fluorescence probe experiment verified that BP@AgNPs promoted the generation of reactive oxygen species, which could disrupt bacteria membrane, damage DNA and oxide proteins, and finally lead to bacteria apoptosis. As a result, the scaffold possessed strong antibacterial efficiency with a bactericidal rate of 97% under light irradiation. Moreover, the scaffold also exhibited good cytocompatibility. This work highlighted a new strategy to develop photocatalytic antibacterial scaffold for bone implant application.


Assuntos
Nanopartículas Metálicas , Prata , Antibacterianos/farmacologia , Luz , Testes de Sensibilidade Microbiana , Fósforo , Prata/farmacologia
9.
Sensors (Basel) ; 22(15)2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35898048

RESUMO

Low Earth Orbit (LEO) satellites have stronger received signals and more rapid geometry changes than Global Navigation Satellite System (GNSS) satellites, making them attractive for positioning, navigation, and timing (PNT) applications. Due to the low altitude, the LEO constellation requires more satellites to cover the entire globe and more Pseudo Random Noise (PRN) codes to realize Code Division Multiple Access (CDMA), which means greater receiver storage resources and receiver acquisition time. In this paper, different from the traditional methods that assign a unique PRN code to each satellite, we propose a novel method in which several satellites share the same PRN code, and simply demonstrate the feasibility and benefits of this method. To determine the minimum number of PRN codes needed for a constellation, we build a mathematical model. After the algorithm comparison, we improve the recursive largest first (RLF) algorithm so that it has a higher running speed and a smaller approximate optimal solution within a certain time period. By studying polar-orbiting and walker constellations, we find that if other satellite parameters remain the same, the higher the orbital altitude is, the more PRN codes are needed, and no matter what the orbital inclination is, the minimum number of PRN codes remains the same. Overall, it is feasible and meaningful for several satellites sharing the same PRN code to save storage resources and reduce the satellite acquisition time of the receiver. If this new technology is applied, the storage resources and the average satellite acquisition time of the receiver will be, at most, one-third of previous ones.

10.
Nanotechnology ; 32(45)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34330108

RESUMO

Black phosphorous (BP) is recognized as an effective reinforcement for polymer scaffold because of its excellent mechanical property and biocompatibility. Nevertheless, its poor stability in physiological environment limits its application in bone repair. In this work, BP was modified with dopamine by self-polymerization approach (donated as BP@PDA) to improve its stability, and then was introduced into poly-L-lactic acid (PLLA) scaffold fabricated by selective laser sintering technology. Results showed the compressive and tensile strength of PLLA/BP@PDA scaffold were improved by 105% and 50%, respectively. The enhanced strength was ascribed to the increased stability of BP and the improved compatibility of BP@PDA with PLLA matrix after modifying with polydopamine. Simultaneously, the bioactivity of PLLA scaffold was significantly improved. It was attributed to that BP@PDA provided the sustained source ofPO43-ions which could capture Ca2+ions from physiological medium to facilitatein situbiomineralization, thereby promoting cell adhesion, proliferation and differentiation. This study demonstrated the great potential of BP@PDA in bone repair.

11.
Anal Bioanal Chem ; 413(23): 5811-5820, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34302183

RESUMO

Remdesivir is a nucleotide analog prodrug that has received much attention since the outbreak of the COVID-19 pandemic in December 2019. GS-441524 (Nuc) is the active metabolite of remdesivir and plays a pivotal role in the clinical treatment of COVID-19. Here, a robust HPLC-MS/MS method was developed to determine Nuc concentrations in rat plasma samples after a one-step protein precipitation process. Chromatographic separation was accomplished on Waters XBrige C18 column (50 × 2.1 mm, 3.5 µm) under gradient elution conditions. Multiple reaction monitoring transitions in electrospray positive ion mode were m/z 292.2 → 163.2 for Nuc and 237.1 → 194.1 for the internal standard (carbamazepine). The quantitative analysis method was fully validated in line with the United States Food and Drug Administration guidelines. The linearity, accuracy and precision, matrix effect, recovery, and stability results met the requirements of the guidelines. Uncertainty of measurement and incurred sample reanalysis were analyzed to further ensure the robustness and reproducibility of the method. This optimized method was successfully applied in a rat pharmacokinetics study of remdesivir (intravenously administration, 5 mg kg-1). The method can act as a basis for further pharmacokinetic and clinical efficacy investigations in patients with COVID-19. Graphical abstract.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/sangue , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Adenosina/sangue , Adenosina/farmacocinética , Adenosina/normas , Monofosfato de Adenosina/sangue , Monofosfato de Adenosina/farmacocinética , Monofosfato de Adenosina/normas , Alanina/sangue , Alanina/farmacocinética , Alanina/normas , Animais , Antivirais/farmacocinética , Antivirais/normas , Limite de Detecção , Masculino , Controle de Qualidade , Ratos , Ratos Sprague-Dawley , Padrões de Referência , Reprodutibilidade dos Testes
12.
Appl Opt ; 59(4): 918-922, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32225228

RESUMO

A novel method, to the best of our knowledge, of fiber transfer delay (FTD) measurement based on phase quantization and delay synthesis is proposed and demonstrated. By detecting the differential phase shifts of a set of frequency-multiplied RF signals transmission through the fiber link with and without the FTD under the test, the ${2}\pi $2π phase ambiguity problem can be solved. To avoid the phase quantization error near the digital quantization boundary, a self-check and error-correction method is proposed so as to greatly improve the reliability of measurement. In the experiment, the measurement repeatability around 0.018 ps within a period of 80 s is achieved for a back-to-back fiber link, and a test resolution of 0.03 ps is proved with a motorized tunable delay line. The system is available for measurement of a large FTD range up to 100 µs with no dead zone.

13.
Langmuir ; 35(13): 4498-4508, 2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30845805

RESUMO

Membrane materials with special wettability for separating oil-water mixtures have gradually become one of the research hotspots. However, oily wastewater usually has very strong corrosiveness, which puts forward high requirements for the chemical stability of the separation membrane. In addition, oil droplets may block the pores, resulting in the decrease of separation efficiency or even separation failure. Herein, biomimetic TiO2-titanium meshes (BTTMs) with switchable wettability were successfully fabricated by one-step dip coating of poly(vinylidene difluoride) and modified TiO2 suspension on the titanium meshes. The simple and efficient preparation method will facilitate the promotion of this smart material. Due to the controlled wettability, the BTTM can separate water or oil from an oil-water mixture as required. When the BTTM was immersed in strong corrosive solution or liquid nitrogen, the wettability did not change much, showing the good stability of the BTTM. Furthermore, the BTTM also has self-healing ability, self-recovery anti-oil-fouling properties, and self-cleaning behavior, which help it resist oil pollution and improve its recyclability. This study provides a simple and efficient strategy for fabricating a stable smart surface for on-demand controllable treatment of corrosive oily wastewater.

14.
Appl Opt ; 58(8): 2127-2131, 2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30874083

RESUMO

A tunable optoelectronic oscillator (OEO)-based photonic radio frequency (RF) heterodyne receiver with the capability of image frequency rejection is proposed and experimentally demonstrated. The OEO incorporating a dual-electrode Mach-Zehnder modulator (DEMZM) operates as a high quality local oscillator (LO) and a broadband mixer simultaneously, with one electrode port of the DEMZM used for the feedback of the generated LO signal and the other port for receiving external RF signals. Two channels of immediate frequency (IF) signals can be achieved in optical domain by beating the +1-order sideband of LO with the +1-order sideband of input RFs and beating the -1-order sideband of LO with the -1-order sideband of input RFs correspondingly. Through setting the bias angle of the DEMZM at π/4 or 5π/4 and quadrature combining of the two channels of the IF signal, the combined IF signal down-converted from the target RF signal gets enhanced due to the in-phase sum of two channels, while the combined IF signal down-converted from the image frequency can be rejected due to out-of-phase sum of two channels. In the experiment, the input RF signals with operating frequency range from 8.85 to 14.85 GHz are successfully received with the image rejection ratio reaching 42.6 dB, and the spurious free dynamic range of the system is better than 94.8 dB Hz2/3.

15.
J Vet Pharmacol Ther ; 42(5): 511-517, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31162674

RESUMO

The pharmacokinetic properties of amoxicillin (AMX) and clavulanic acid (CLV) were studied in healthy cats following single intravenous and oral dosage of 10 mg/kg of AMX and 2.5 mg/kg of CLV. The drug concentrations in plasma were determined by a high-performance liquid chromatographic-tandem mass spectrometry (LC-MS-MS) method validated for canine plasma and further subjected to noncompartmental analysis. After intravenous injection, no significant difference (p > 0.05) was found in the volume of distribution of these two compounds. In addition, AMX and CLV were both rapidly eliminated from plasma with a clearance of 0.453 and 0.921 L hr-1  kg-1 , respectively; however, a quicker elimination was observed for CLV (p < 0.01). After oral administration, both drugs were characterized by rapid absorption with an absorption half-life of 1.10 and 0.70 hr for AMX and CLV, respectively. Significant differences were observed between their absorption rates (p < 0.05). However, the oral bioavailabilities of AMX and CLV (75.57% and 98.15%, respectively) were not statistically different (p > 0.05). A total intravenous or oral dose at 12.5 mg/kg of AMX and CLV (4:1) is predicted to be effective for treating those bacterial species isolated from cats with a minimum inhibitory concentration (MIC) of ≤0.25 µg/ml for 12 hr, based on a time above the MIC (T > MIC) of 40%.


Assuntos
Combinação Amoxicilina e Clavulanato de Potássio/farmacocinética , Antibacterianos/farmacocinética , Gatos/sangue , Administração Oral , Combinação Amoxicilina e Clavulanato de Potássio/administração & dosagem , Combinação Amoxicilina e Clavulanato de Potássio/sangue , Animais , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Área Sob a Curva , Estudos Cross-Over , Feminino , Meia-Vida , Injeções Intravenosas , Masculino
16.
Sensors (Basel) ; 18(6)2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29914140

RESUMO

This paper is concerned to the fire localization problem for large-space buildings. Two kinds of circular fire source arrangement localization methods are proposed on the basis of the dynamic optimization technology. In the Range-Point-Range frame, a dynamic optimization localization is proposed to globally estimate the circle center of the circular arrangement to be determined based on all the point estimates of the fire source. In the Range-Range-Range frame, a dynamic optimization localization method is developed by solving a non-convex optimization problem. In this way, the circle center and the radius are obtained simultaneously. Additionally, the dynamic angle bisector method is evaluated. Finally, a simulation with three simulation scenes is provided to illustrate the effectiveness and availability of the proposed methods.

17.
J Vet Pharmacol Ther ; 41(6): 919-923, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30043978

RESUMO

As a semisynthetic tetracycline derivative, doxycycline (α-6-deoxy-5-hydroxytetracycline) is a time-dependent bacteriostatic agent. It is being widely used in the broiler husbandry in China. In this study, doxycycline was orally administered by gavage to 10 healthy broiler chickens at the dose of 20 mg/kg body weight every 24 hr for five total treatments. Plasma samples were collected from each animal at 5, 10, 20, and 30 min and 1, 2, 4, 6, 8, and 12 hr after the first dose, at 0.25, 0.5, 0.45, 1, 2, 3, 4, 6, 7, 13.5, 24, 36, 48, 60, and 72 hr after the last dose. Additional plasma samples were collected at a 24-hr interval during the dosing period (immediately prior to each oral administration). The doxycycline concentrations were determined by high-performance liquid chromatography with an ultraviolet detector and subjected to noncompartmental analysis. Then, the pharmacokinetics profiles were compared after the first and last oral doses. After the first dosing, the elimination half-life, area under the concentration-time curve from 0 hr to ∞, peak concentration, time to reach peak concentration, and volume of distribution per fraction absorbed were determined as 7.78 hr, 94.19 µg·hr/ml, 5.65 µg/ml, 3.50 hr, and 2,502.65 ml/kg, respectively, while the corresponding values of these parameters after the last dose were 19.90 hr, 121.08 µg·hr/ml, 5.71 µg/ml, 7.25 hr, and 5,285.28 ml/kg, respectively. After multiple oral doses, the absorption and elimination both became slower, while the distribution was more extensive than that following a single dose. However, after multiple oral doses, accumulation of doxycycline in plasma was not observed with an average accumulation factor of 1.11.


Assuntos
Antibacterianos/farmacocinética , Galinhas/sangue , Doxiciclina/farmacocinética , Administração Oral , Animais , Antibacterianos/administração & dosagem , Área Sob a Curva , Disponibilidade Biológica , Doxiciclina/administração & dosagem , Esquema de Medicação , Meia-Vida , Distribuição Tecidual
18.
J Vet Pharmacol Ther ; 41(5): 739-745, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29892973

RESUMO

The pharmacokinetic profiles of florfenicol (FF) or florfenicol amine (FFA) in crucian carp were compared at different water temperatures after single intramuscular administration of FF at 10 mg/kg bodyweight. The concentrations of FF and FFA were determined by a high-performance liquid chromatography method, and then, the concentration versus time data were subjected to compartmental analysis using a one-compartment open model. At the water temperatures of 10, 20, and 25°C, the peak concentrations (Cmax s) of FF were 2.28, 2.29, and 2.34 µg/ml, respectively, while those of FFA were 0.42, 0.71, and 0.82 µg/ml, respectively. And the absorption half-life (t1/2ka ) of FF was 0.21, 0.19, and 0.21 hr, while the elimination half-life (t1/2kel ) was 31.66, 24.77, and 21.48 hr, respectively. For FFA, the formation half-life (t1/2kf ) was 3.85, 8.97, and 12.43 hr, while the t1/2kel was 58.34, 30.27, and 21.22 hr, respectively. The results presented here demonstrated that the water temperature had effects on the elimination of both FF and FFA and the formation of FFA. Based on the T > MIC values calculated here, to treat the infections of bacterial with MIC value ≤ 0.5 µg/ml, FF intramuscularly given at 10 mg/kg bodyweight with a 72-hr interval is sufficient at the water temperature of 10°C, while the intervals of 60 and 48 hr were needed at 20 and 25°C, respectively. But to treat bacterial with higher MIC values, more FF or FF at 10 mg/kg BW but with shorter intervals should be intramuscularly given to the infected fish.


Assuntos
Antibacterianos/farmacocinética , Tianfenicol/análogos & derivados , Animais , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Cromatografia Líquida de Alta Pressão/veterinária , Carpa Dourada/sangue , Carpa Dourada/metabolismo , Injeções Intramusculares/veterinária , Temperatura , Tianfenicol/administração & dosagem , Tianfenicol/sangue , Tianfenicol/farmacocinética
19.
Clin Infect Dis ; 63(1): 115-21, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27025832

RESUMO

BACKGROUND: The 90-90-90 targets recommended by the Joint United Nations Programme on HIV/AIDS require strengthening human immunodeficiency virus (HIV) care, which includes diagnosis, linkage to and retention in care, assessment for treatment suitability, and optimization of HIV treatment. We sought to quantify patient engagement along the continuum, 10 years after introduction of Chinese HIV care policies. METHODS: We included patients from Shandong, China, who were diagnosed with HIV from 1992 to 2013. Records were obtained from the HIV/AIDS Comprehensive Response Information Management System to populate a 7-step HIV care continuum. Pearson χ(2) test and multivariate logistic regression were used for analysis. RESULTS: Of 6500 estimated HIV-infected persons, 60.1% were diagnosed, of whom 41.9% received highly active antiretroviral therapy (HAART). Only 59.6% of patients on HAART and 15% of all infected persons achieved viral suppression. Children infected by mother-to-child transmission (MTCT) and persons infected by intravenous drug use were less likely to be linked to and retained in care (odds ratio [OR], 0.33 [95% confidence interval {CI}, .14-.80] and OR, 0.58 [95% CI, .40-.90], respectively). Persons tested in custodial institutions were substantially less likely to be on HAART (OR, 0.22 [95% CI, .09-.59]) compared with those tested in medical facilities. Patients on HAART infected by homosexual or heterosexual transmission and those infected by MTCT were less likely to achieve viral suppression (OR, 0.18 [95% CI, .09-.34]; OR, 0.12 [95% CI, .06-.22]; OR, 0.07 [95% CI, .02-.20], respectively). CONCLUSIONS: Our report suggests, at the current rate, Shandong Province has to accelerate HIV care efforts to close disparities in HIV care and achieve the 90-90-90 goals equitably.


Assuntos
Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Disparidades em Assistência à Saúde/estatística & dados numéricos , Adolescente , Adulto , Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Criança , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
20.
Langmuir ; 31(30): 8235-42, 2015 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-26172585

RESUMO

Six novel siloxane-based surface-active ionic liquids (SAILs)--siloxane ammonium carboxylate [Si(n)N(2)-CA(1), (n = 3, 4)]--were designed and synthesized. Their melting points, surface activities, and self-aggregation behavior in aqueous solution were studied. The results showed that because of the bulky hydrophobic siloxane chains at the end of the tail, all six siloxane-based SAILs are room-temperature ionic liquids (RT-SAILs). The introduction of the siloxane group can reduce the melting point of ionic liquids to below room temperature and can promote the micellization and aggregation behavior more efficiently. These siloxane-based SAILs can greatly reduce the surface tension of water, as shown by the critical aggregation concentration (γCAC) values of 20 mN·m(-1); all six siloxane RT-SAILs can form a vesicle spontaneously in aqueous solution, indicating potential uses as model systems for biomembranes and vehicles for drug delivery.

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