A polytriazole synthesized by 1,3-dipolar polycycloaddition showing aggregation-enhanced emission and utility in explosive detection.

The metal-free click polymerizations (MFCPs) of activated alkynes and azides have become a powerful technique for the preparation of functional polytriazoles. Recently, a new MFCP of activated azide and alkyne has been established, but no functional polytriazole is prepared. In this paper, polytriazole PIa with aggregation-enhanced emission (AEE) characteristics is prepared by this efficient polymerization in excellent yield (97.9%). PIa is thermally stable, with 5% loss of its weight at temperature as high as 440 °C. Thanks to its unique AEE feature of PIa, its nanoaggregates can be used to detect explosives with a superamplification quenching effect.

Modified Nuss procedure with a novel steel bar in patients with pectus excavatum post-congenital heart surgery.

OBJECTIVES: Pectus excavatum (PE) can be secondary in patients who underwent sternotomy for cardiac surgery. Retrosternal adhesions increase the complexity and risk of traditional Nuss repair. Thus, we summarized the outcomes of our modified Nuss procedure using a newly designed bar. METHODS: A retrospective analysis was performed on 35 patients who underwent modified PE repair after open heart surgery from January 2011 to July 2019. The surgery was performed using a novel bar with no need for intraoperative reshaping and rotation, assisted by thoracoscopy and subxiphoid incision when necessary. RESULTS: There were 19 males and 16 females with a median age of 5.3 years (interquartile range, 4.1-10.9) at PE repair. All patients underwent the modified procedure uneventfully with no death. The median operating time was 70 min. Twenty-nine (82.9%) patients required subxiphoid incision assistance. There was 1 case (2.8%) with unexpected sternotomy due to intraoperative bleeding. The median length of postoperative hospital stay was 4 days. During the median 3.5 years of follow-up, no bar dislocation was found and 30 (85.7%) patients had their bars removed with no recurrence recorded. After PE repair, the Haller index improved significantly (2.6 ± 0.4 vs 4.9 ± 1.3, P < 0.05) and further decreased till the time of bar removal (2.5 ± 0.4 vs 2.6 ± 0.4, P < 0.05). All patients were satisfied with the cosmetic outcome. CONCLUSIONS: The novel bar can be placed and removed easily with a low rate of adverse events. This modified Nuss procedure seems to be a safe, effective and convenient approach for the management of PE after cardiac surgery.

Aggregation-induced emission of tetraphenylethene derivative as a fluorescence method for probing the assembling/disassembling of amphiphilic molecules.

The aggregation-induced emission (AIE) of a 1,2-diphenyl-1,2-di(p-tolyl)ethene (TPE) was explored as a novel fluorescence method for probing the assembling/disassembling of amphiphilic molecules. The fluorescence intensity was able to monitor the formation of micelles and determine the critical micelle concentration (CMC) of surfactants. The temperature-dependent micellization of the pharmaceutically important PEO-PPO-PEO copolymer, Pluronic F127, was further studied by using the TPE fluorescence spectrum intensity. Our results showed good agreement with those reported in the literature by using other methods. The special advantage of the AIE probe method was further explored to determine the assembling/disassembling process of the colored amphiphilic molecule, 1-[4-(3-phenylazophenoxy)butyl]triethylamine bromide (AzoC4), whose CMC value has not previously been described. Since the TPE fluorescence signal mainly comes from the aqueous phase, not from the inside of hydrophobic core, it provides a possible platform to study the CMC of those colored surfactants. Based on the novel fluorescence properties of TPE in the aggregated and dispersed states, one can conclude that the TPE method is a promising method for the determination of the CMC and critical micellization temperature (CMT), particularly having a special advantage to determine the assembling/disassembling process of colored amphiphilic molecules.

Dentofacial changes after anterior crossbite correction using a lingual arch with finger springs.

BACKGROUND/PURPOSE: Anterior crossbite correction is common in orthodontic treatment; however, few studies have discussed the change with cephalometric measurements. The purpose of this study was to evaluate the dentofacial changes in anterior crossbite correction by using an upper lingual arch with finger springs. MATERIALS AND METHODS: This retrospective study included 30 patients (13 female and 17 male). According to the number of crossbite teeth, the patients were divided into three groups. We used paired t test, Kruskal-Wallis test, Mann-Whitney U test, and multiple regression analysis to perform statistical analysis. RESULTS: According to overall treatment changes, the dental changes included overjet increase, overbite decrease, upper incisor proclination, lower incisor retroclination and intrusion, upper molar distal tipping with extrusion, and lower molar intrusion. These dental changes resulted in clockwise mandibular rotation and lip position change. Anterior crossbite correction did not require increasing bite appliances. According to multiple regression analysis, the change in overjet was associated with the position of the upper and lower incisor crown tips. The mean rate of upper incisor movement in the horizontal direction was 2.5 mm/mo. The treatment duration exhibited no significant difference among the three groups. CONCLUSION: Lingual arch with finger springs was effective in anterior crossbite correction regardless of the number of crossbite teeth.

Primary placement of a hydroxyapatite-coated sleeve in bioceramic orbital implants.

PURPOSE: To study a new surgical option of primary placement of a hydroxyapatite-coated sleeve into the Bioceramic implant during enucleation or evisceration. DESIGN: Retrospective, observational case series. METHODS: A standard enucleation or evisceration was performed, followed by the preplacement of a hydroxyapatite-coated sleeve into the Bioceramic implant. Care must be taken to ensure the sleeve has been positioned centrally when the implant is put inside the orbital socket. Complications such as sleeve exposure, Bioceramic implant exposure, and infection were closely observed. RESULTS: Twenty-seven patients were treated in above fashion with five enucleation and 22 evisceration procedures. Five of the sleeves have exposed spontaneously during 1 to 4 months after original surgery. They had no further complication, except for one sleeve around which there were visible Bioceramic spicules attributable to long-term corticosteroid usage. The remaining 22 sleeves that did not spontaneously expose pursued secondary exposure of the sleeve and peg insertion by the conjunctival cutdown procedure 3 months postoperatively. One sleeve was medially positioned far away from the implant center. Re-insertion of new sleeve and peg was scheduled 2 weeks later. One additional sleeve was obliquely positioned after conjunctival cutdown procedure. Fortunately, all 27 patients were successfully fitted with a peg-coupled prosthesis with good motility. CONCLUSIONS: Primary placement of a hydroxyapatite-coated sleeve into the Bioceramic implants has several advantages, including high patient acceptance, technical simplicity, and an office-based conjunctival cutdown pegging procedure. By avoiding the expense of postoperative imaging studies and additional prosthetic modification, a more rapid and efficient rehabilitation is possible.

A novel modified Nuss procedure for pectus excavatum: a new steel bar.

PURPOSE: The purpose of this article is to introduce a new modified Nuss procedure for pectus excavatum and to describe the configuration of the new steel bar. DESCRIPTION: We applied a novel method with a new steel bar for minimally invasive surgical correction of pectus excavatum. The procedure was performed with a new steel bar through bilateral thoracic minimally invasive incisions using a thoracoscope for guidance. The bar was installed or removed by pushing and pulling without turning it over. EVALUATION: One hundred forty-seven patients with pectus excavatum underwent this novel modified Nuss procedure. All patients had a satisfactory orthopedic result at discharge. There was no perioperative death or cardiac perforation. During the follow-up period, 134 patients underwent bar removal. Of the 134 cases, the initial orthopedic and functional results were excellent in 121 patients (90.3%) and good in 13 patients (9.7%). No patient had recurrence. CONCLUSIONS: This novel modified Nuss procedure is a safe, effective, and convenient treatment for pectus excavatum.

A strategy for fabrication of a three-dimensional tissue construct containing uniformly distributed embryoid body-derived cells as a cardiac patch.

Growing three-dimensional (3D) scaffolds that contain more than a few layers of seeded cells in vitro is crucial for the creation of thick and viable cardiac tissues in vivo. Embryonic stem cells (ESCs) have been used as an alternative cell source for cardiac repair; however, dissociated ESCs show poor viability in the scaffold and do not form the embryoid body (EB)-like structures. In this study, a strategy intended for cultivating EB-derived cells (EBDCs) uniformly in a porous 3D tissue scaffold was developed. This strategy employed techniques of formation of spherically symmetric EBs in a thermo-responsive hydrogel system, production of cell sheets of EBDCs in a similar hydrogel system coated with collagen and fabrication of sliced porous tissue scaffolds. The prepared EBs were collected and plated evenly in the cell-sheet culture system. After 8 days in culture, a continuous sheet of EBDCs with cell beating was obtained; our qPCR and flow cytometric analyses showed that the collagen-coated on the cell-sheet culture system can significantly enhance the population of cardiac-lineage cells. The produced EBDC sheets were then sandwiched into the sliced porous tissue scaffold. After reculture, the seeded EBDCs were redistributed uniformly throughout the scaffold, with a significant increase in mechanical strength. Cardiac-specific myosin heavy chain and alpha-actinin were expressed for some cells grown in the scaffold, while connexin 43 was clearly expressed at the cell borders. Additional studies such as employing purification techniques to enrich the population of cardiomyocytes are needed to further improve the developed tissue constructs as a bioengineered cardiac patch.

A fluorescent thermometer operating in aggregation-induced emission mechanism: probing thermal transitions of PNIPAM in water.

Poly(N-isopropylacrylamide) was labelled using a fluorogen with an aggregation-induced emission feature by direct polymerization; the label served as a fluorogenic probe that reveals fine details in the thermal transitions in the aqueous solution of the polymer; the working mode was readily tuned between non-monotonic and monotonic by changing the labelling degree of the polymer.

Novel method of forming human embryoid bodies in a polystyrene dish surface-coated with a temperature-responsive methylcellulose hydrogel.

A temperature-responsive hydrogel composed of aqueous methylcellulose (MC) blended with distinct concentrations of PBS was prepared and characterized. The developed MC hydrogel underwent a sol-gel reversible transition upon heating or cooling at approximately 32 degrees C. This temperature-responsive hydrogel was employed to coat the surface of a polystyrene dish and used to cultivate human embryonic stem (hES) cell clumps for the formation of embryoid bodies (EBs) in liquid suspension culture (LSC-MC/PS). The conventional hanging drop culture (HDC) and LSC in the uncoated polystyrene dish (LSC-PS) or in the Corning Ultralow-Attachment plate (LSC-ULAP) were used as controls. The results indicated that LSC-PS failed to generate EBs in an efficient manner, whereas the efficiencies of EB formation observed in LSC-ULAP and LSC-MC/PS were significantly greater than in HDC. The hES cells within the EBs were shown to express molecular markers specific for representative cells from the three embryonic germ layers. These results indicated that the MC-coated dish can be used to produce a large scale of hES cell derivatives through the formation of EBs.

[Experimental studies on tissue engineered esophagus reconstructed with artificial biodegradable scaffold].

OBJECTIVE: To verify adhesion and growth ability of canine esophageal epithelial cells (EECs) on the poly (lactic-co-glycolic acid) (PLGA), a three-dimensional biodegradable polymer scaffold, and to reconstruct the canine esophagus by the tissue engineering. METHODS: Free canine EECs isolated from adult dogs by esophagoscopy were seeded onto the PLGA scaffolds precoated with collagen type IV after the first passage by the in vitro culture. Then, the composites of the cell-scaffold were respectively cultured in vitro and in the abdominal cavity of the dog in vivo. After different periods, the cell-seeded scaffolds were assessed by histological HE staining, scanning electron microscopy, and immunohistochemical analysis. RESULTS: The cells displayed a cobblestone-shaped morphology that was characteristic of the epithelial cells and were stained to be positive for cytokeratin, which indicated that the cells were EECs. The canine EECs were well distributed and adhered to the PLGA scaffolds, and maintained their characteristics throughout the culture period. After the culture in vivo for 4 weeks, the cell-seeded scaffolds looked like tissues. CONCLUSION: PLGA scaffolds precoated with collagen type IV can be suitable for adhesion and proliferation of EECs, and can be used as a suitable tissue engineering carrier of an artificial esophagus.