Factors for poor oral health in long-term childhood cancer survivors.

BACKGROUND: Survivors of childhood cancer are at risk for therapy-related dental diseases. The purpose of the study was to investigate the associations between clinical, socioeconomic, and demographic factors and oral diseases in the St. Jude Lifetime Cohort (SJLIFE) participants. METHODS: We performed a retrospective medical chart review and evaluated longitudinal self-reported dental outcomes in 4856 childhood cancer survivors and 591 community controls participating in the St. Jude Lifetime Cohort (SJLIFE) study. Univariate and multivariable logistic regression models were used to assess the impact of socioeconomic factors, treatment exposures and patient demographics on dental outcomes. RESULTS: Cancer survivors were more likely to report microdontia (odds ratio (OR) = 7.89, 95% confidence interval (CI) [4.64, 14.90]), abnormal root development (OR = 6.19, CI [3.38, 13.00]), hypodontia (OR = 2.75, CI [1.83, 4.33]), enamel hypoplasia (OR = 4.24, CI [2.9, 6.49]), xerostomia (OR = 7.72, CI [3.27, 25.10]), severe gingivitis (OR = 2.04, CI [1.43, 3.03]), and ≥ 6 missing teeth (OR = 3.73, CI [2.46, 6.00]) compared to controls without cancer history. Survivors who received classic alkylating agents (OR = 1.6, CI [1.36, 1.88]), anthracycline antibiotics (OR = 1.22, CI [1.04, 1.42] or radiation therapy potentially exposing the oral cavity (OR = 1.48, CI [1.26, 1.72]) were more likely to report at least one dental health problem after controlling for socioeconomic factors, age at last follow-up and diagnosis, other treatment exposures, and access to dental services. Survivors who had radiation therapy potentially exposing the oral cavity (OR = 1.52, CI [1.25, 1.84]) were also more likely to report at least one soft tissue abnormality after controlling for socioeconomic factors, age at last follow-up and diagnosis, other treatment exposures, and access and utilization of dental services. CONCLUSIONS: Childhood cancer survivors have a higher prevalence of oral-dental abnormalities than the controls without a cancer history. Cancer treatment, socioeconomic factors, and access to oral health care contribute to the prevalence of dental abnormalities.

Mechanism of biofilm formation on a hydrophobic polytetrafluoroethylene membrane during the purification of surface water using direct contact membrane distillation (DCMD), with especial interest in the feed properties.

The impact of feed water quality on biofilm formation during membrane distillation (MD) was investigated in this study, particularly emphasizing the interrelationship between organics, salts, and microbes. Two types of typical natural surface waters in Nanjing, China, were chosen as feed solutions for long-term MD operation, including the Qinhuai River and Xuanwu Lake. The biofilms that developed under different feed water qualities exhibited distinct Foulant compositions and structures, causing different flux decline trends for the MD system. Accordingly, two typical patterns of biofilm formation were suggested for the MD operation of the two different kinds of surface waters in this study. Organics from a primal feed solution and dead bacteria were the key to the establishment of a biofilm on the membrane, and this needs to be effectively removed from the MD system through pre-treatment and process control strategies. Finally, a feasible strategy for MD biofouling control was suggested.

A comparison study: Periodontal practice approach of dentists and dental hygienists.

OBJECTIVES: The aim of this study was to investigate periodontal practice methods of dentists and dental hygienists to compare their knowledge and treatment approach in managing periodontal disease. METHODS: An electronic survey was designed to assess and capture three aspects of data: (a) knowledge of periodontics; (b) practice approaches in non-surgical periodontal therapy; and (c) factors affecting clinical care. The survey was distributed to dentists and dental hygienists who graduated from the same dental school within 5 years (2012-2016). Results were analysed by chi-square test, Fisher's exact test and logistic regression model. RESULTS: Out of total 117 participants, 111 of them reported their profession (n = 77 in the dental programme, n = 34 in the dental hygiene programme). The results showed no statistical difference in basic periodontal knowledge between dentists and dental hygienists (P = .12). Only 13% of the surveyed population identified appropriate recall intervals for periodontal maintenance and more dental hygienists reported periodontal re-evaluations being performed within their offices compared with dentists (91% vs 70%, P = .02). Almost half of the participants who reportedly performed periodontal re-evaluations (46%) charged for the re-evaluation procedure, despite it not being covered by dental insurance. More hygienists reported being familiar with and performing adjunct therapy compared to dentists in the study (P < .01). CONCLUSION: In general, dentists and hygienists in the study were found to have similar periodontal knowledge and practice approaches. However, differences in performing periodontal re-evaluation and adjunct therapy were significant. Further studies are needed to investigate clinical barriers that impact evidence-based periodontal care.

Chemical Degradation of Polyacrylamide during Hydraulic Fracturing.

Polyacrylamide (PAM) based friction reducers are a primary ingredient of slickwater hydraulic fracturing fluids. Little is known regarding the fate of these polymers under downhole conditions, which could have important environmental impacts including decisions on strategies for reuse or treatment of flowback water. The objective of this study was to evaluate the chemical degradation of high molecular weight PAM, including the effects of shale, oxygen, temperature, pressure, and salinity. Data were obtained with a slickwater fracturing fluid exposed to both a shale sample collected from a Marcellus outcrop and to Marcellus core samples at high pressures/temperatures (HPT) simulating downhole conditions. Based on size exclusion chromatography analyses, the peak molecular weight of the PAM was reduced by 2 orders of magnitude, from roughly 10 MDa to 200 kDa under typical HPT fracturing conditions. The rate of degradation was independent of pressure and salinity but increased significantly at high temperatures and in the presence of oxygen dissolved in fracturing fluids. Results were consistent with a free radical chain scission mechanism, supported by measurements of sub-µM hydroxyl radical concentrations. The shale sample adsorbed some PAM (∼30%), but importantly it catalyzed the chemical degradation of PAM, likely due to dissolution of Fe2+ at low pH. These results provide the first evidence of radical-induced degradation of PAM under HPT hydraulic fracturing conditions without additional oxidative breaker.

A novel superchilling storage - ice glazing (SS-IG) approach using biopolymer-based composite hydrogel to delay microbiological spoilage and organic oxidation of preserved tilapia.

BACKGROUND: Most aquatic products are highly susceptible to deterioration and microbial spoilage during storage. Cold storage is a frequently used method to preserve them. However, products preserved by traditional frozen method are prone to suffer damage. This can significantly impair the quality of the products. To solve the problem, this work established a novel superchilling storage-ice glazing (SS-IG) approach using chitosan-catechin composite material. It can maximize the postmortem quality of preserved products during storage, avoiding damage. RESULTS: During storage at -1.5 ± 0.2 °C for 25 days, the SS-IG approach using 5 g L-1 chitosan and 1∼3 g L-1 catechin as IG layers can effectively enhance the postmortem quality of preserved tilapia fillets. The sensory qualities of these fillets were effectively maintained. The microbial counts in these fillets were strongly suppressed. Oxidative rancidity in these fillets was observably inhibited. Less biogenic amine was produced in these fillets. CONCLUSION: The results indicated that the SS-IG with chitosan-catechin composite-ice glazing layers can be effective in maintaining the postmortem quality of tilapia fillets. This will have a wide potential application. © 2018 Society of Chemical Industry.

[Response surface method for optimization of asiatic acid nanoparticles modified with PEG and its enhancing effects on intestinal absorption].

A solvent diffusion method was used to prepare pegylated asiatic acid (AA) loaded nanostructured lipid carriers (p-AA-NLC). Then central composite design-response surface method was used to obtain optimum condition for preparation technology of p-AA-NLC, where PEG/lipid ratio was 8.0% and AA/lipid ratio was 22.0%. Under the optimum condition, the system had particle size of (111.2±2.9) nm, Zeta potential of (-37.1±0.9) mV, drug loading of (15.4±0.2)% and entrapment efficiency greater than 90%. The deviations between observed values and predicated values were all below 5%, indicating that the established model had a good predictability. Meanwhile, a low-speed single pass perfusion model of rat in situ was set up to estimate the absorption kinetics of p-AA-NLC in small intestine, where the effective permeability (Peff), absorption rate constant (Ka) and other parameters were used to evaluate the drug absorption. It turned out that Peff and Ka in p-AA-NLC group were significantly higher than those in unmodified group (P<0.05), indicating that asiatic acid loaded nanostructured lipid carriers (AA-NLC) could enhance the effects on intestinal absorption after being modified with hydrophilic PEG.

Decoding of quantum dots encoded microbeads using a hyperspectral fluorescence imaging method.

We presented a decoding method of quantum dots encoded microbeads with its fluorescence spectra using line scan hyperspectral fluorescence imaging (HFI) method. A HFI method was developed to attain both the spectra of fluorescence signal and the spatial information of the encoded microbeads. A decoding scheme was adopted to decode the spectra of multicolor microbeads acquired by the HFI system. Comparison experiments between the HFI system and the flow cytometer were conducted. The results showed that the HFI system has higher spectrum resolution; thus, more channels in spectral dimension can be used. The HFI system detection and decoding experiment with the single-stranded DNA (ssDNA) immobilized multicolor beads was done, and the result showed the efficiency of the HFI system. Surface modification of the microbeads by use of the polydopamine was characterized by the scanning electron microscopy and ssDNA immobilization was characterized by the laser confocal microscope. These results indicate that the designed HFI system can be applied to practical biological and medical applications.

Optimization for extracellular polymeric substances extraction of microbial aggregates.

The extracellular polymeric substances (EPS) are important macromolecular components in microbial aggregates. The three EPS extraction methods - ultrasound + cation exchange resins (CER) + sulfide, ultrasound + formamide + NaOH, and ultrasound + heat - were investigated in the study, and the component differences of extracted EPS from the loose flocs and dense aerobic granules were compared using chemical analysis and three-dimensional excitation-emission matrix (3D-EEM). Results showed that the contents of EPS were extracted effectively by ultrasound + formamide + NaOH and ultrasound + heat methods, and the ultrasound + CER + sulfide method did not extract the polysaccharides (PS) or protein (PN) contents from the sludge samples. The 3D-EEM analysis indicated that the nature of peak B/D, peak C/E/F, and peak A/G were attributed to PN-like, humic acid-like and fulvic acid-like fluorophores. All fluorophores can be detected from the EPS extracted through the ultrasound + heat method. Hopefully this will provide more information about the EPS interaction mechanism of microbial aggregates.

Advanced oxidation process/coagulation coupled with membrane distillation (AOP/Coag-MD) for efficient ammonia recovery: Elucidating biofouling control performance and mechanism.

The inadequate understanding of the biofouling formation mechanism and the absence of effective control have inhibited the commercial application of membrane distillation (MD). In this study, an advanced oxidation process (AOP)/coagulation-coupled (Coag) membrane distillation system was proposed and exhibited the potential for MD ammonia recovery (recovery rate: 94.1%). Extracellular polymeric substances (EPS) and soluble microbial products (SMP) components such as humic acid and tryptophan-like proteins were disrupted and degraded in the digestate. The curtailment and sterilizing efficiency of AOP on biofilm growth was also verified by optical coherence tomography (OCT) in situ real-time monitoring and confocal laser scanning microscopy (CLSM). Peroxymonosulfate (PMS) was activated to generate sulfate (SO4•-) and hydroxyl radicals (HO•), which altered the microbial community. After oxidative treatment, 16 S rRNA sequencing indicated that the dominant phylum of the microbial community evolved into Firmicutes. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis demonstrated that free radicals produced by PMS could disrupt cells' signaling molecules and interactions. In conjunction with these analyses, the mechanisms of response to free radical attack by Gram-negative bacteria, Gram-positive bacteria, and fungi were revealed. This research provided new insights into the field of membrane fouling control for membrane technology resource recovery processes, broadening the impact of AOP applications on microbiological response and fate in the environment.

Fabrication of lignosulfonate-derived porous carbon via pH-tunable self-assembly strategy for efficient atrazine removal.

Herein, a straightforward protocol was developed for the one-pot synthesis of N-doped lignosulfonate-derived carbons (NLDCs) with a tunable porous structure using natural amino acids-templated self-assembly strategy. Specifically, histidine was employed as a template reagent, leading to the preparation of 10-NLDC-21 with remarkable characteristics, including the large specific surface area (SBET = 1844.5 m2/g), pore volume (Vmes = 1.22 cm3/g) and efficient adsorption for atrazine (ATZ) removal. The adsorption behavior of ATZ by NLDCs followed the Langmuir and pseudo-second-order models, suggesting a monolayer chemisorption nature of ATZ adsorption with the maximum adsorption capacity reached up to 265.77 mg/g. Furthermore, NLDCs exhibited excellent environmental adaptability and recycling performance. The robust affinity could be attributed to multi-interactions including pore filling, electrostatic attraction, hydrogen bonding and π-π stacking between the adsorbents and ATZ molecules. This approach offers a practical method for exploring innovative bio-carbon materials for sewage treatment.

Distinct oral-associated gastric microbiota and Helicobacter pylori communities for spatial microbial heterogeneity in gastric cancer.

The gastric microbial community plays a fundamental role in gastric cancer (GC), and the two main anatomical subtypes of GC, non-cardia and cardia GC, are associated with different risk factors (Helicobacter pylori for non-cardia GC). To decipher the different microbial spatial communities of GC, we performed a multicenter retrospective analysis to characterize the gastric microbiota in 223 GC patients, including H. pylori-positive or -negative patients, with tumors and paired adjacent normal tissues, using third-generation sequencing. In the independent validation cohort, both dental plaque and GC tumoral tissue samples were collected and sequenced. The prevalence of H. pylori and oral-associated bacteria was verified using fluorescence in situ hybridization (FISH) assays in GC tumoral tissues and matched nontumoral tissues. We found that the vertical distribution of the gastric microbiota, at the upper, middle, and lower third sites of GC, was likely an important factor causing microbial diversity in GC tumor tissues. The oral-associated microbiota cluster, which included Veillonella parvula, Streptococcus oralis, and Prevotella intermedia, was more abundant in the upper third of the GC. However, H. pylori was more abundant in the lower third of the GC and exhibited a significantly high degree of microbial correlation. The oral-associated microbiota module was co-exclusive with H. pylori in the lower third site of the GC tumoral tissue. Importantly, H. pylori-negative GC patients with oral-associated gastric microbiota showed worse overall survival, while the increase in microbial abundance in H. pylori-positive GC patients showed no difference in overall survival. The prevalence of V. parvula in both the dental plaque and GC tissue samples was concordant in the independent validation phase. We showed that the oral-associated species V. parvula and S. oralis were correlated with overall survival. Our study highlights the roles of the oral-associated microbiota in the upper third of the GC. In addition, oral-associated species may serve as noninvasive screening tools for the management of GC and an independent prognostic factor for H. pylori-negative GCs. IMPORTANCE: Our study highlights the roles of the oral-associated microbiota in the upper third of gastric cancer (GC).We showed that the oral-associated species Veillonella parvula and Streptococcus oralis were correlated with overall survival. In addition, oral-associated species may serve as noninvasive screening tools for the management of GC and an independent prognostic factor for Helicobacter pylori-negative GCs.

Hydroxycamptothecin liposomes inhibit collagen secretion and induce fibroblast apoptosis in a postlaminectomy rabbit model.

OBJECTIVE: To design and attest the role of hydroxycamptothecin liposomes (L-HCPT) as a new delivery system to prevent epidural scar adhesions after laminectomy in a rabbit model. METHODS: Lumbar laminectomies at L6 were performed on 18 mature male New Zealand rabbits. The rabbits were randomly divided into three groups: (I) a cotton pad soaked with 0.05 % hydroxycamptothecin (HCPT) solution was kept on the laminectomy area for 5 min before the layers were sutured (HCPT group); (II) 25 mg of liposomes containing 0.01 % HCPT was implanted on the laminectomy area (L-HCPT group); and (III) the laminectomy area was flushed with saline (control group). The rabbits were killed 4 weeks after the operation. Macroscopic evaluation and histological analysis of epidural scar adhesion were employed with hematoxylin-eosin and Masson staining, followed by hydroxyproline (Hyp) quantification and magnetic resonance imaging (MRI) of postoperative rabbit scar tissues. The epidural scar area and number of fibroblasts in the scar tissue were also evaluated. RESULTS: In the laminectomy sites of rabbits treated with HCPT or L-HCPT, the dura mater and nerve root were clean without evident scar adhesion. Hyp concentration was significantly lower in these two groups compared with the saline-control group. On the other hand, the MRI of postoperative rabbits showed apparent decreased fibrosis around the dura mater in these two groups compared with the control group. In addition, the epidural scar area and the number of fibroblasts were significantly lower in the two groups compared with the control group. CONCLUSION: These results demonstrate that the treatment of postlaminectomy wounds with L-HCPT may reduce and prevent the severity of adhesion.

Preclinical teaching of periodontal surgical concepts using common instructional models: A comparative assessment.

OBJECTIVES: Some commonly used models utilized for teaching periodontal surgical techniques to dental students include pig mandible and periodontal typodonts. Currently, no study compares the learning and teaching outcomes following the use of one model to the other. This study is aimed at evaluating the effectiveness of the preclinical laboratory component on student understanding of concepts taught in the periodontal surgical course and assessing students' and faculty members' satisfaction with the instructional models. METHODS: As part of the surgical periodontics course, 98 students took the final exam, with eighty students participating in only the pig mandible session and twenty-three students participating in both the pig jaw mandible and an additional session utilizing periodontal typodonts under the supervision of ten periodontal faculty members. Examination scores of students attending or not attending the laboratory session were analyzed by a two-sample t-test. A questionnaire evaluating the effectiveness of both models was given to faculty members and students who participated in both laboratory sessions. These results were analyzed by paired t-test. RESULTS: Participation in the laboratory sessions did not significantly impact the final exam scores (p = 0.722). Students who had better didactic performance in the course performed better in the final exam, irrespective of laboratory participation. Both students and faculty members preferred typodont to the pig mandibles in learning or teaching periodontal surgical concepts, but both felt gaining flap management and flap refection experience to be better with the pig mandible model without statistical significance (p = 0.119 and p = 0.070, respectively). CONCLUSION: Within the limitations of this study, we can conclude that laboratory sessions did not significantly improve student performance on the exam. Students and faculty members generally gave positive feedback on both instructional models. Periodontal typodont could be an alternative model for teaching dental students, periodontal surgical concepts.

Craniomaxillofacial Bone Segmentation and Landmark Detection Using Semantic Segmentation Networks and an Unbiased Heatmap.

Craniomaxillofacial (CMF) surgery always relies on accurate preoperative planning to assist surgeons, and automatically generating bone structures and digitizing landmarks for CMF preoperative planning is crucial. Since the soft and hard tissues of the CMF regions possess complicated attachment, segmenting the CMF bones and detecting the CMF landmarks are challenging problems. In this study, we proposed a semantic segmentation network to segment the maxilla, mandible, zygoma, zygomatic arch, and frontal bones. Then, we obtained the minimum bounding box around the CMF bones. After cropping, we used the top-down heatmap landmark detection network, similar to the segmentation module, to identify 18 CMF landmarks from the cropping patch. In addition, an unbiased heatmap encoding method was proposed to generate actual landmark coordinates in the heatmap. To overcome quantization effects in the heatmap-based landmark detection networks, the distribution-prior coordinate representation of medical landmarks (DCRML) was proposed to utilize the prior distribution of the encoding heatmap, approximating the accurate landmark coordinates in heatmap decoding by Taylor's theorem. The encoding and decoding method can easily contribute to other existing landmark detection frameworks based on heatmaps; consequently, these approaches can readily benefit without changing model structure. We used prior segmentation knowledge to enhance the semantic information around the landmarks, increasing landmark detection accuracy. The proposed framework was evaluated by 100 healthy persons and 86 patients from multicenter cooperation. The mean Dice score of our proposed segmentation network achieved over 88 %; in particular, the mandible accuracy was approximately 95%. The mean error of landmarks was 1.84 ±1.32 mm.

Seasonal shift of water quality in China Yangtze River and its impacts on membrane fouling development during the drinking water supply by membrane distillation system.

Membrane distillation (MD) technique is increasingly regarded as a promising process for drinking water supply and wastewater treatment owing to its great water purification and usage of renewable energy. Like other membrane separation processes, the membrane fouling issue is widely considered as the main obstacle for real applications of large-scale MD systems. Feedwater characteristics, as the predominant factors for membrane fouling layer formation, mostly determined the membrane fouling trend of MD. Thus the impacts of seasonal shifts of initial feedwater quality on the MD membrane fouling were detailedly researched in this study, and the biofilm development mechanism was especially explored. The bacterial community structure of membrane biofilms was clearly clarified in MD runs of Yangtze River waters that collected in four seasons. The results revealed that the winter run posed a quite sharp flux drop, while a relatively milder flux decline behaviour was seen for other groups despite of the higher bacteria concentration of initial feedwaters. The poorer water quality in winter induced the establishment of a rather thick biofilm on the MD membrane, in which the biofilm-forming bacteria (Gammaproteobacteria and Alphaproteobacteria) and organic matters (EPS) were remarkably observed. Comparatively, a relatively thin biofilm containing abundant live cells and fewer organics finally formed in summer and autumn runs, causing a mitigated flux decline trend. Hence, it can be inferred that the membrane flux decline of MD was likely to be more sensitive to the organic attachment on the membrane in comparison with the bacteria adhesion. Finally, a three-phase pretreatment method was suggested for MD fouling control, including heating course, sterilization course, and filtration course.

A Breathable, Reusable, and Zero-Power Smart Face Mask for Wireless Cough and Mask-Wearing Monitoring.

We herein introduce a lightweight and zero-power smart face mask, capable of wirelessly monitoring coughs in real time and identifying proper mask wearing in public places during a pandemic. The smart face mask relies on the compact, battery-free radio frequency (RF) harmonic transponder, which is attached to the inner layer of the mask for detecting its separation from the face. Specifically, the RF transponder composed of miniature antennas and passive frequency multiplier is made of spray-printed silver nanowires (AgNWs) coated with a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) passivation layer and the recently discovered multiscale porous polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (SEBS) substrate. Unlike conventional on-chip or on-board wireless sensors, the SEBS-AgNWs/PEDOT:PSS-based RF transponder is lightweight, stretchable, breathable, and comfortable. In addition, this wireless device has excellent resilience and robustness in long-term and repeated usages (i.e., repeated placement and removal of the soft transponder on the mask). We foresee that this wireless smart face mask, providing simultaneous cough and mask-wearing monitoring, may mitigate virus-transmissive events by tracking the potential contagious person and identifying mask-wearing conditions. Moreover, the ability to wirelessly assess cough frequencies may improve diagnosis accuracy for dealing with several diseases, such as chronic obstructive pulmonary disease.

Subdural neural interfaces for long-term electrical recording, optical microscopy and magnetic resonance imaging.

Though commonly used, metal electrodes are incompatible with brain tissues, often leading to injury and failure to achieve long-term implantation. Here we report a subdural neural interface of hydrogel functioning as an ionic conductor, and elastomer as a dielectric. We demonstrate that it incurs a far less glial reaction and less cerebrovascular destruction than a metal electrode. Using a cat model, the hydrogel electrode was able to record electrical signals comparably in quality to a metal electrode. The hydrogel-elastomer neural interface also readily facilitated multimodal functions. Both the hydrogel and elastomer are transparent, enabling in vivo optical microscopy. For imaging, cerebral vessels and calcium signals were imaged using two-photon microscopy. The new electrode is compatible with magnetic resonance imaging and does not cause artifact images. Such a new multimodal neural interface could represent immediate opportunity for use in broad areas of application in neuroscience research and clinical neurology.

Transforming Growth Factor-ß Signaling Regulates Tooth Root Dentinogenesis by Cooperation With Wnt Signaling.

Proper differentiation of odontoblasts is crucial for the development of tooth roots. Previous studies have reported the osteogenic/odontogenic potential of pre-odontoblasts during root odontoblast differentiation. However, the underlying molecular pathway that orchestrates these processes remains largely unclear. In this study, ablation of transforming growth factor-ß receptor type 2 (Tgfbr2) in root pre-odontoblasts resulted in abnormal formation of root osteodentin, which was associated with ectopic osteogenic differentiation of root odontoblasts. Disrupting TGF-ß signaling caused upregulation of Wnt signaling characterized by increased Wnt6, Wnt10a, Tcf-1, and Axin2 expression. Interestingly, inhibiting Wnt signaling by deleting Wntless (wls) in Osteocalcin (Ocn)-Cre; Tgfbr2 fl/fl ; Wls fl/fl mice or overexpressing the Wnt antagonist Dkk1 in Ocn-Cre; Tgfbr2 fl/fl ; ROSA26 Dkk1 mice decreased ectopic osteogenic differentiation and arrested odontoblast differentiation. Our results suggest that TGF-ß signaling acts with Wnt signaling to regulate root odontogenic differentiation.

Preparation and characterization of zedoary turmeric oil-loaded insulin-modified sterically stabilized liposomes.

The poor selectivity of anticancer drugs often leads to their multiplicate dose-limiting toxicities in humans, which severely restricts their clinical application. In this study, a novel liposomal formulation of zedoary turmeric oil (ZTO) targeting the insulin receptor (IR) was prepared by covalently conjugating insulin to the terminal of the polyethylene glycol (PEG) chain of sterically stabilized liposomes. In vitro assays indicated that a higher uptake of insulin-modified sterically stabilized liposomes (ISSLs) was observed in SMMC-7721 hepatocarcinoma cells overexpressing insulin receptors. IC(50) values of ISSLs, NTLs (nontargeted liposomes), and ZTO injection (free ZTO) against SMMC-7721, determined by MTT assays, were 157.2, 256.7, and 43.3 microg x ml(-1), respectively. Plasma-clearance profiles of ZTO in the liposomal formulations were then compared with that of ZTO injection. The liposomal formulations showed much longer terminal half-lives (11.24 and 14.73 hours for ISSLs and NTLs, respectively) than that of ZTO injection (1.45 hours). All results above indicated the ISSLs were potentially useful for the treatment of IR (+) tumors and are worthy of further investigation.

Effect of salt and metal accumulation on performance of membrane distillation system and microbial community succession in membrane biofilms.

Membrane distillation (MD) works as a potential technology for the "zero liquid discharge" water treatment owing to its high concentration brine tolerance. The continuous accumulation of salts and metals in the MD system during the "zero liquid discharge" water treatment inevitably posed remarkable impacts on the biofilm formation as well as the MD performance. Hence, the biofouling mechanism of MD was deeply researched in this study with an emphasis on the roles of salt-stress (NaCl) and metal-stress (Zn and Fe) in biofilm development. The membrane flux decline of MD was effectively mitigated by the appearance of NaCl and ZnO, while that was significantly aggravated under the metal-stress of Fe. Considering the serious membrane scaling caused by NaCl crystals, a sharp flux decline was seen for the NaCl group during the later stage of MD operation. Basing on the 16S rDNA and 16S rRNA analysis, heat-stress, salt-stress, and metal-stress all posed certain impacts on the biofouling development in the MD system, and a more remarkable influence was observed for metal-stress. Under the salt-stress from NaCl, a thin biofilm containing high biovolume of dead cells finally formed, in which the bacterial community mainly consisted of halotolerant and thermophile species. Owing to the Zn2+-stress and oxidation-stress mechanisms of ZnO, the bacteria in the MD system were largely dead and live bacterial community in biofilms was dominated by some gram-negative species. Under the metal-stress from Fe, a rather thick biofilm containing higher biovolume of live cells clearly developed, in which the prevailing species could secret large amounts of EPS and accumulate metabolites around cells as biological surfactants, inducing aggravated membrane biofouling and high risk of membrane wetting.