High power femtosecond semiconductor lasers based on saw-toothed master-oscillator power-amplifier system with compressed ASE.

High power femtosecond semiconductor laser based on saw-toothed taper mode-locked laser and amplifier was demonstrated with compressed amplified spontaneous emission (ASE). The external-cavity mode-locked taper laser generated the clean optical pulses without any sub-pulse components. A semiconductor optical amplifier (SOA) with tilted taper waveguide and saw-toothed edge reduced evidently the ASE background. The saw-tooth microstructures were optimized and it was found that the saw-tooth of right-right angled triangle showed the best effect. The ratio of the maximum intensity to background radiation was increased by 21.9% and the power was increased by 30.5% due to the saw-tooth microstructure in the SOA. The pulse duration of 495 fs and a peak power over 1.5 kW with repetition rate of 579 MHz were realized after a double-pass grating compressor.

Design and Evaluation of Hydrophilic Matrix System Containing Polyethylene Oxides for the Zero-Order Controlled Delivery of Water-Insoluble Drugs.

The aim of this study was to design a polyethylene oxide (PEO) binary hydrophilic matrix controlled system and investigate the most important influence(s) on the in vitro water-insoluble drug release behavior of this controlled system. Direct-compressed PEO binary matrix tablets were obtained from a variety of low viscosity hydrophilic materials as a sustained agent, using anhydrous drugs as a model drug. Water uptake rate, swelling rate, and erosion rate of matrices were investigated for the evaluation of the PEO hydrophilic matrix systems. The effect of the dose, the solubility of water-insoluble drug, and the rheology of polymers on in vitro release were also discussed. Based on the in vitro release kinetics study, three optimized PEO binary matrices were selected for further research. And, these PEO binary matrices had shown the similar release behavior that had been evaluated by the similarity factor f 2. Further study indicated that they had identical hydration, swelling, and erosion rate. Moreover, rheology study exhibited the similar rheological equation of Herschel-Bulkley and their viscosity was also within the same magnitude. Therefore, viscosity plays the most important role to control drug release compared to other factors in PEO binary matrix system. This research provides fundamental understanding of in vitro drug release of PEO binary hydrophilic matrix tablets and helps pharmaceutical workers to develop a hydrophilic controlled system, which will effectively shorten the process of formulation development by reducing trial-and-error.

Intranasal administration of butorphanol benefits old patients undergoing H-uvulopalatopharyngoplasty: a randomized trial.

BACKGROUND: To evaluate intranasal administration of butorphanol on postoperative pain and early postoperative cognitive dysfunction in old patients undergoing H-uvulopalatopharyngoplasty (H-UPPP). METHODS: A total of 260 male patients (65 to 77 years old) with obstructive sleep apnea hypopnea syndrome and scheduled for H-UPPP were divided randomly to receive intranasal butorphanol, intravenous butorphanol, intranasal fentanyl, or intravenous saline (controls). The definition of preemptive analgesia is that the tested drugs are given before anesthesia induction. Visual analog scale (VAS) and Bruggrmann comfort scale (BCS) scores were recorded at postoperative 1, 6, 12, 18, 24, 36, and 48 h. Postoperative cognitive dysfunction (POCD) was evaluated by Mini-Mental State Examination (MMSE) scores assessed one day before, and 1, 3, and 7 days postsurgery. RESULTS: Compared with control group, those given preemptive analgesia required significantly less sufentanil during surgery, had less pain at postoperative 6-12 h; those given butorphanol experienced less nausea and vomiting, less pain at postoperative 6-24 h, and less POCD. Compared with patients given fentanyl, those given butorphanol required significantly less postoperative fentanyl, had less pain at postoperative 18-24 h, less nausea and vomiting, and less POCD. Compared with patients given intravenous butorphanol, those who received butorphanol by nasal route required significantly less postoperative fentanyl, had less pain at 36 and 48 h, and less POCD. CONCLUSION: Intranasal administration of butorphanol is safe and effective, reducing postoperative usage of analgesics and the incidence of POCD in old patients undergoing H-UPPP. TRIAL REGISTRATION: ChiCTR-TRC-14004121.

Distribution of enteroviruses in hospitalized children with hand, foot and mouth disease and relationship between pathogens and nervous system complications.

BACKGROUND: To explore the relationship between enteroviruses and hospitalized children with hand, foot and mouth disease (HFMD) complicated with nervous system disease. 234 hospitalized HFMD patients treated in Shengjing Hospital, Liaoning Province were analyzed retrospectively. Based on the presence and severity of nervous system disease, the patients were grouped as follows: general patients, severely ill patients, critically ill patients and fatal patients. Based on the detected pathogen, the patients were grouped as follows: Enterovirus 71 (EV71) infection, coxsackie A16 (CA16) infection and other enterovirus (OE) infection. RESULTS: Of the 423 hospitalized patients, most were admitted in July 2010(129/423, 30.5%). Enteroviruses were detected in 177(41.8%). 272/423 patients were male (64.3%), and fatal patients had the greatest proportion of male patients (p < 0.05). EV71 infection was found in 89/423 patients (21%). CA16 infection was detected in 8/423 patients (16.1%). Compared to group CA16, patients in group EV71 were hospitalized earlier, and the duration of hospitalization was longer (p < 0.05). Of the 92 patients with nervous system damage, 65 were infected with EV71 and 19 were infected with CA16. Among these CA16 infected patients, 2 had brainstem encephalitis and 1 had AFP. There were more patients with nervous system dysfunction in group EV71 than in groups CA16 or OE (p < 0.05). The 5 fatalities all occurred in group EV71 patients (p < 0.05). Infection with EV71 was most likely to cause neurogenic pulmonary edema (p < 0.05). Patients in group EV71 had a higher rate of suffering from coma and limb movement disorder than patients in groups CA16 or OE (p < 0.05). CONCLUSION: The disease progresses faster in EV71-infected HFMD patients. These patients are more likely to suffer nervous system damage, neurogenic pulmonary edema, severe sequelae or death. CA16 and other enteroviruses can also cause HFMD with severe nervous system complications.

Artificial intelligence modeling and molecular docking to analyze the laccase delignification process of rice straw by Comamonas testosteroni FJ17.

The laccase enzymatic characteristics and delignification processes of rice straw by Comamonas testosteroni FJ17 were investigated. Artificial intelligence modeling and molecular docking revealed the specific functional properties involved in the interaction between laccase and lignin compounds with a maximum laccase activity of 2016.7 U L-1 at 24 h. Scanning electron microscopy and X-ray diffractometer analysis confirmed that laccase caused fractures and holes on the surface of rice straw, where crystallinity decrease from 45.3 to 39.9%, and lignin content decreased from 19.0 to 10.3%. Gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry analysis showed that the main delignification process for laccase was via ß-o-4 and α-aryl ether cleavage, which generated several small molecular products. The laccase gene was cloned and bioinformatics analysis presented 317 amino acids with a predicted molecular weight of 33.13 kDa. Finally, laccase protein was found to have low binding energies with all lignin compounds tested, and lignin compounds were oxidized by laccase through hydrogen-bonding interactions with the amino acid residues.

A composite System Combining Self-Targeted Carbon Dots and Thermosensitive Hydrogels for Challenging Ocular Drug Delivery.

We developed a composite system combining self-targeted carbon dots and thermosensitive in situ hydrogels for ocular drug delivery of diclofenac sodium (DS). DS-CDC-HP nanoparticles were prepared by loading DS on the surface of CDC-HP via electrostatic interactions. An orthogonal experimental design was selected to screen the optimal thermosensitive hydrogel matrices and then DS-CDC-HP nanoparticles were embedded to form the composite system. The physicochemical properties and release behavior of this system were characterized, and in vivo fluorescence imaging was carried out. Corneal penetrability and in vitro cellular studies (cytotoxicity, cell imaging and cell uptake) were performed to test the feasibility and potential of this ocular delivery system. Finally, the optimal gel matrix consisting of Poloxamer 407: Poloxamer 188: HPMC E50 was 21:1:1 (w/v %), and the gelation temperature before adding artificial tear fluid was 26.67°C and 34.29°C, respectively. This system has the characteristics of biphasic drug release. In addition, the corneal penetrability and in vivo fluorescence study indicated that corneal transmittance was enhanced and drug retention time was extended. Cellular studies revealed that the DS-CDC-HP-Gel has good cytocompatibility and CD44 targeting. In summary, this composite system combines carbon dots with hydrogels, offering new potential for ocular drug delivery.

[Pharmaceutical characteristics of brucine stealth liposomes].

OBJECTIVE: To prepare brucine stealth liposomes and compare the in vitro characteristics with brucine conventional liposomes. METHOD: Brucine stealth liposomes and conventional liposomes were both prepared by ammonium sulfate transmembrane gradients. The encapsulation efficiency, particle size, in vitro release profiles and stability were compared respectively. RESULT: The encapsulation efficiency of brucine stealth liposomes and conventional liposomes were (80.7 +/- 0.5)%, and (80.5 +/- 0.3)%, respectively. The mean paricle sizes were 103.5 nm and 169. 4 nm, respectively. Whether rat plasma was added or not, the release rate and degree of brucine stealth liposomes were significantly lower than those of conventional liposomes. Brucine stealth liposomes were more stable than conventional liposomes. CONCLUSION: As the antitumor durg delivery system, the in vitro characteristics of brucine stealth liposomes are more satisfactory than the corresponding conventional liposomes.

Zero-Order Controlled Delivery of Gliclazide from Polyethylene Oxides Matrix Tables: In vitro and In vivo Evaluation.

BACKGROUND: In recent years, controlled and sustained release drug delivery system has become the focus of pharmaceutical researchers. Some technologies aimed to develop the controlled and sustained release of the drug, which used to be administered several times a day and generate plasma concentration fluctuation. As all, a controlled drug release rate has always been a goal pursued by researchers. This paper introduced a controlled delivery hydrophilic matrix system, and evaluated their relevance between in vitro and in vivo behaviors. METHODS: The matrix tablets were fabricated by direct powder compression method. Single-factor test and the orthogonal experimental design were used to find out the optimal formulation. And the in vivo pharmacokinetics study was also evaluated in this paper. RESULTS: The amount of WSR N301 and low viscosity materials significantly affect the drug release. Compared with commercially available sustained-release tablets Diamicron®, the pharmacokinetics parameters of these matrix tablets exhibited similar blood profiles, and other parameters such as prolonged Tmax, Cmax, MRT and similar bioavailability. However, this matrix system showed unstable blood profiles in comparison with two-layer-core osmotic pump tablet. The IVIVC study suggested that there was a good correlation between absorption in vivo and drug release in vitro. CONCLUSION: Zero-order controlled drug release of hydrophilic matrix system has the simpler manufacture process. And it will be a promising system to control drug release. Due to the disadvantage of hydrophilic matrix tablets in vivo release, for further research the zero-order delivery of PEO matrix tablets system, some pharmaceutical technology are needed to decrease the influence of gastrointestinal peristalsis. Therefore, the study of polyethylene oxide hydrophilic matrix tablets provides a promising formulation for promoting the development of a drug delivery system.

[Characteristics of circulatory disturbance and the treatment of severe hand-foot-and-mouth disease].

OBJECTIVE: To investigate the characteristics of circulatory disturbance and treatment of severe hand-foot-and-mouth disease (HFMD). METHOD: The clinical characteristics, laboratory findings, therapy and outcome of 22 severe HFMD patients were retrospectively analyzed. RESULT: All the 22 severe HFMD patients came from the countryside. All these patients had encephalitis. Fifteen cases had myocardial injury. All had symptoms of sympathetic excitation and 17 cases had hypertension [(128 ± 16)/(81 ± 14) mm Hg (1 mm Hg = 0.133 kPa)]. Fourteen cases had exacerbation with rapid decline of blood pressure [(61 ± 12)/(33 ± 12) mm Hg]. In cardiorespiratory failure stage, 13 patients had neurogenic pulmonary edema accompanied by circulatory failure and 12 cases had a lower glasgow scores (less than 7). Myocardial injury and ECG change were found in some cases. Inotropic and pressor drugs were given in patients with circulatory collapse. Five cases received fluid resuscitation due to refractoriness to inotropic drugs. Nine patients received blood purification. Seventeen survived and 5 cases died due to circulatory failure. CONCLUSION: Circulation failure of severe HFMD is the main cause of death. Early and appropriate circulation support is very important to reduce mortality.