Mechanical Strain Induces and Increases Vesicular Release Monitored by Microfabricated Stretchable Electrodes.

Exocytosis involving the fusion of intracellular vesicles with cell membrane, is thought to be modulated by the mechanical cues in the microenvironment. Single-cell electrochemistry can offer unique information about the quantification and kinetics of exocytotic events; however, the effects of mechanical force on vesicular release have been poorly explored. Herein, we developed a stretchable microelectrode with excellent electrochemical stability under mechanical deformation by microfabrication of functionalized poly(3,4-ethylenedioxythiophene) conductive ink, which achieved real-time quantitation of strain-induced vesicular exocytosis from a single cell for the first time. We found that mechanical strain could cause calcium influx via the activation of Piezo1 channels in chromaffin cell, initiating the vesicular exocytosis process. Interestingly, mechanical strain increases the amount of catecholamines released by accelerating the opening and prolonging the closing of fusion pore during exocytosis. This work is expected to provide revealing insights into the regulatory effects of mechanical stimuli on vesicular exocytosis.

Versatile Construction of Biomimetic Nanosensors for Electrochemical Monitoring of Intracellular Glutathione.

The current strategies for nanoelectrode functionalization usually involve sophisticated modification procedures, uncontrollable and unstable modifier assembly, as well as a limited variety of modifiers. To address this issue, we propose a versatile strategy for large-scale synthesis of biomimetic molecular catalysts (BMCs) modified nanowires (NWs) to construct functionalized electrochemical nanosensors. This design protocol employs an easy, controllable and stable assembly of diverse BMCs-poly(3,4-ethylenedioxythiophene) (PEDOT) composites on conductive NWs. The intrinsic catalytic activity of BMCs combined with outstanding electron transfer ability of conductive polymer enables the nanosensors to sensitively and selectively detect various biomolecules. Further application of sulfonated cobalt phthalocyanine functionalized nanosensors achieves real-time electrochemical monitoring of intracellular glutathione levels and its redox homeostasis in single living cells for the first time.

Soft Electrodes for Electrochemical and Electrophysiological Monitoring of Beating Cardiomyocytes.

Many cells in vivo have their inherent motions, which involve numerous biochemical and biophysical signals synergistically regulating cell behavior and function. However, existing methods offer little information about the concurrently chemical and physical responses of dynamically pulsing cells. Here, we report a soft electrode with an electrospun poly(3,4-ethylenedioxythiophene) (PEDOT)-based nanomesh to fully comply with spontaneous motions of cells. Moreover, this electrode demonstrated excellent electrical conductivity, electrochemical performance and cellular biocompatibility. Cardiomyocytes cultured thereon exhibited autonomous and rhythmic contractility, and synchronously induced mechanical deformation of the underlying electrode, which allowed real-time monitoring of nitric oxide release and electrophysiological activity of cardiomyocytes. This work provides a promising way toward recording chemical and electrical signals of biological systems with their natural motions.

Dental follicles promote soft tissue management in surgical exposure of labially impacted maxillary canine.

BACKGROUND: The present study aimed to report a technically improved operation on the surgical exposure of labially impacted maxillary canine, elaborating the management of soft tissue to achieve better aesthetic results, and post-treatment periodontal health. METHODS: Patients sought orthodontic treatment with unilateral labially impacted maxillary canines were selected in this study. The impacted teeth were assigned to the experimental group and contralateral unimpacted canines were assigned to the control group. The impacted canines were surgically exposed with dissected dental follicle (DF) stitching to muscle and mucosa surrounding the crowns. The gingival index (GI), probing depth (PD), the width of the keratinized gingiva (WKG), gingival scars (GS), bone loss (BL), and apical root resorption (ARR) were recorded after the removal of the fixed appliance. A two-sample t-test was used for independent samples for parametric variables. RESULTS: A total of 24 patients with unilateral maxillary canine impaction were successfully treated. The outcomes of GI, WKG, GS, BL, and ARR did not indicate statistical significance between the experimental group and the control group. CONCLUSIONS: The preservation of DF promotes soft tissue management in combined surgical and orthodontic treatment of labially impacted maxillary canine to achieve better periodontal status. Trial Registration Chinese Clinical Trial Registry ChiCTR2000029091, 2020-01-12.

Pretreatment of corn cob in [EMIM][OAc] and [EMIM][OAc]/ethanol (water).

High cost and high viscosity of ionic liquid restricted its commercial application in pretreatment of lignocellulose. Water and ethanol were used as additive in [EMIM][OAc] to pretreat corn cob at moderate temperature (< 100 °C). It was found that enzyme hydrolysis (EH) sugar yield was increased with the increase of IL content. The largest EH sugar yield of 68.8% was obtained when pure IL was used. However, for [EMIM][OAc]/ethanol, the EH sugar yield as high as 66.9% was gained when the IL content was 80%, which was comparable to that for pure IL pretreatment. In addition, Kamlet-Taft parameter was calculated to characterize the polarity solvency of binary liquid phase, to illustrate the underlying reason for the increase of EH sugar and the lignin removal. Finally, to demonstrate the crystalline and microstructure change after pretreatment, XRD and SEM were performed for the raw materials and the pretreated samples.

Real-time computerised tomography assisted porous tantalum implant in ARCO stage I-II non-traumatic osteonecrosis of the femoral head: minimum five-year follow up.

PURPOSES: This study was established to investigate the medium-term clinical effect of real-time CT assisted porous tantalum implant for the treatment of ARCO stage I-II non-traumatic osteonecrosis of the femoral head (ONFH). METHODS: This study comprised 24 ONFH patients (29 hips) who were treated with intra-operative real-time CT accurate rapid positioning assisted drilling decompression, lesion removal and porous tantalum implant. Harris score, VAS score and imaging in pre-operation and follow-up period were recorded. RESULTS: The average operative time and intra-operative blood loss were 72.6 min and 158.8 ml, respectively. The mean follow-up was 5.4 years. No femoral head penetrating, wound infection, and death occurred. Harris and VAS score improved significantly (73.78 vs. 88.11; 7.13 vs. 2.66) at last follow-up (P < 0.05). The functional improvement and pain relief rate was 100% at six months after operation. The effective rate was 86.21% at 12 months after operation and last follow-up. Five pre-operative ARCO stage I hips had no radiographic progress. Meanwhile, four among the 24 ARCO stage II hips progressed into stage III between eight and 12 months after surgery, among which two progressed into stage IV and two remained in stage III at the last follow-up. The average value of Kerboul combined necrotic angle was 263.24°. There was no progress in Kerboul combined necrotic angle among the grades 2 and 3 patients. However, among the six cases at grade 4, four cases with post-operative progress, two patients converted to THA. CONCLUSIONS: Our technique is safety and effective in the treatment of ARCO stage I-II non-traumatic ONFH.

Polydimethylsiloxane-Paper Hybrid Lateral Flow Assay for Highly Sensitive Point-of-Care Nucleic Acid Testing.

In nucleic acid testing (NAT), gold nanoparticle (AuNP)-based lateral flow assays (LFAs) have received significant attention due to their cost-effectiveness, rapidity, and the ability to produce a simple colorimetric readout. However, the poor sensitivity of AuNP-based LFAs limits its widespread applications. Even though various efforts have been made to improve the assay sensitivity, most methods are inappropriate for integration into LFA for sample-to-answer NAT at the point-of-care (POC), usually due to the complicated fabrication processes or incompatible chemicals used. To address this, we propose a novel strategy of integrating a simple fluidic control strategy into LFA. The strategy involves incorporating a piece of paper-based shunt and a polydimethylsiloxane (PDMS) barrier to the strip to achieve optimum fluidic delays for LFA signal enhancement, resulting in 10-fold signal enhancement over unmodified LFA. The phenomena of fluidic delay were also evaluated by mathematical simulation, through which we found the movement of fluid throughout the shunt and the tortuosity effects in the presence of PDMS barrier, which significantly affect the detection sensitivity. To demonstrate the potential of integrating this strategy into a LFA with sample-in-answer-out capability, we further applied this strategy into our prototype sample-to-answer LFA to sensitively detect the Hepatitis B virus (HBV) in clinical blood samples. The proposed strategy offers great potential for highly sensitive detection of various targets for wide application in the near future.

A nonsense mutation in DHTKD1 causes Charcot-Marie-Tooth disease type 2 in a large Chinese pedigree.

Charcot-Marie-Tooth (CMT) disease represents a clinically and genetically heterogeneous group of inherited neuropathies. Here, we report a five-generation family of eight affected individuals with CMT disease type 2, CMT2. Genome-wide linkage analysis showed that the disease phenotype is closely linked to chromosomal region 10p13-14, which spans 5.41 Mb between D10S585 and D10S1477. DNA-sequencing analysis revealed a nonsense mutation, c.1455T>G (p.Tyr485(∗)), in exon 8 of dehydrogenase E1 and transketolase domain-containing 1 (DHTKD1) in all eight affected individuals, but not in other unaffected individuals in this family or in 250 unrelated normal persons. DHTKD1 mRNA expression levels in peripheral blood of affected persons were observed to be half of those in unaffected individuals. In vitro studies have shown that, compared to wild-type mRNA and DHTKD1, mutant mRNA and truncated DHTKD1 are significantly decreased by rapid mRNA decay in transfected cells. Inhibition of nonsense-mediated mRNA decay by UPF1 silencing effectively rescued the decreased levels of mutant mRNA and protein. More importantly, DHTKD1 silencing was found to lead to impaired energy production, evidenced by decreased ATP, total NAD(+) and NADH, and NADH levels. In conclusion, our data demonstrate that the heterozygous nonsense mutation in DHTKD1 is one of CMT2-causative genetic alterations, implicating an important role for DHTKD1 in mitochondrial energy production and neurological development.

Real-Time Quantification of Nanoplastics-Induced Oxidative Stress in Stretching Alveolar Cells.

Nanoplastics from air pollutants can be directly inhaled into the alveoli in the lungs and further enter blood circulation, and numerous studies have revealed the close relation between internalized nanoplastics with many physiological disorders via intracellular oxidative stress. However, the dynamic process of nanoplastics-induced oxidative stress in lung cells under breath-mimicked conditions is still unclear, due to the lack of methods that can reproduce the mechanical stretching of the alveolar and simultaneously monitor the oxidative stress response. Here, we describe a biomimetic platform by culturing alveoli epithelial cells on a stretchable electrochemical sensor and integrating them into a microfluidic device. This allows reproducing the respiration of alveoli by cyclic stretching of the alveoli epithelial cells and monitoring the nanoplastics-induced oxidative stress by the built-in sensor. By this device, we prove that cyclic stretches can greatly enhance the cellular uptake of nanoplastics with the dependencies of strain amplitude. Importantly, oxidative stress evoked by internalized nanoplastics can be quantitatively monitored in real time. This work will promote the deep understanding about the cytotoxicity of inhaled nanoplastics in the pulmonary mechanical microenvironment.

Femtosecond laser-irradiated crystallization of amorphous Si2Sb2Te3 films and its in-situ characterization by coherent phonon spectroscopy.

Femtosecond laser-irradiation-induced phase change of a new amorphous Si(2)Sb(2)Te(3) film with a good thermal stability and low reset current is studied by coherent phonon spectroscopy. New coherent optical phonons (COP) occur as laser irradiation fluence reaches some threshold, implying laser-induced phase change emerged. The compositions in phase-changed area revealed by COP modes agree well with ones in reported annealed crystallized film, implying laser-induced phase change as crystallization. Pump fluence dependence of COP dynamics reveals good crystallization quality of the phase-changed film, exhibiting promising application of Si(2)Sb(2)Te(3) films in optical phase change memory. Acoustic phonons are also found and identified.

Mechanisms of chitosan-coated poly(lactic-co-glycolic acid) nanoparticles for improving oral absorption of 7-ethyl-10-hydroxycamptothecin.

Chitosan-modified poly(lactic-co-glycolic acid) nanoparticles (CHI/PLGA NPs) loaded with 7-ethyl-10-hydroxycamptothecin (SN-38), named CHI/PLGA/SN-38 NPs, were successfully prepared using an oil-in-water (O/W) solvent evaporation method. The physicochemical properties of the novel NPs were characterized by DLS, Zeta potential, SEM, DSC, XRD, and FTIR. The encapsulation efficiency and drug loading content were 71.83 (±2.77)% and 6.79 (±0.26)%, respectively. In vitro drug release in the simulated gastric juice was lower than that in the intestinal juice. In situ single-pass intestinal perfusion (SPIP) studies indicated a dramatic improvement of drug absorption as a result of the synergistic effect between CHI and PLGA on P-glycoprotein (Pgp) inhibition. CHI/PLGA NPs showed high cellular uptake and low efflux for drugs in Caco-2 cells. The cytotoxicity studies revealed that CHI/PLGA NPs had a transient effect on the membrane integrity, but did not have an influence on cell viability. Based on the in vitro release studies, SPIP, and intracellular drug accumulation and transport investigations, we speculate rationally that CHI/PLGA NPs were mainly internalized in the form of intact NPs, thus escaping the recognition of enterocyte Pgp and avoiding efflux into the apical part of the enterocytes. After partial release of drugs inside the enterocytes, CHI/PLGA interfered with the microenvironment of Pgp and further weakened the Pgp-mediated efflux. Then, the drug-loaded NPs exited via the exocytose effect from the basal part of the enterocytes and entered the blood circulation. These results showed that CHI/PLGA NPs would be smart oral delivery carriers for antineoplastic agents that are also Pgp substrates.

Resveratrol Loaded by Folate-Modified Liposomes Inhibits Osteosarcoma Growth and Lung Metastasis via Regulating JAK2/STAT3 Pathway.

Background: Osteosarcoma is a malignant bone tumor with a high rate of lung metastasis and mortality. It has been demonstrated that resveratrol can inhibit tumor proliferation and metastasis, but its application is limited due to poor water solubility and low bioavailability. In this study, we proposed to prepare folate-modified liposomes loaded with resveratrol to investigate its anti-osteosarcoma effect in vitro and in vivo. Methods: We prepared and characterized resveratrol liposomes modified with folate (denoted as, FA-Res/Lps). The effects of FA-Res/Lps on human osteosarcoma cell 143B proliferation, apoptosis, and migration were investigated by MTT, cell cloning, wound-healing assay, transwell, and flow cytometry. A xenograft tumor and lung metastasis model of osteosarcoma was constructed to study the therapeutic effects of FA-Res/Lps on the growth and metastasis of osteosarcoma in vivo. Results: The FA-Res/Lps were prepared with a particle size of 118.5 ± 0.71 and a small dispersion coefficient of 0.154 ± 0.005. We found that FA-modified liposomes significantly increased resveratrol uptake by osteosarcoma cells 143B in flow cytometric assay, resulting in FA-Res/Lps, which inhibit tumor proliferation, migration and induce apoptosis more effectively than free Res and Res/Lps. The mechanism of action may be associated with the inhibition of JAK2/STAT3 signaling. In vivo imaging demonstrated that FA-modified DiR-modified liposomes significantly increased the distribution of drugs at the tumor site, leading to significant inhibition of osteosarcoma growth and metastasis by FA-Res/Lps. Furthermore, we found that FA-Res/Lps did not cause any adverse effects on mice body weight, liver, or kidney tissues. Conclusion: Taken together, the anti-osteosarcoma effect of resveratrol is significantly enhanced when it is loaded into FA-modified liposomes. FA-Res/Lps is a promising strategy for the treatment of osteosarcoma.

[Effects of Low-density Polyethylene Microplastics on the Growth and Physiology Characteristics of Ipomoea aquatica Forsk].

Microplastic pollution in soil and its toxicological effects have attracted increasing attention from researchers, but the mechanisms of microplastics affecting crop growth and physiology remain unclear. A pot experiment was conducted to evaluate the impacts of various mass concentrations (0%, 0.2%, 5%, and 10%) of low-density polyethylene microplastics (LDPE MPs) on the germination rate, photosynthetic pigment content, biomass, antioxidant enzyme activity, soluble protein, and soluble sugar content of water spinach (Ipomoea aquatica Forsk). The results showed that LDPE MPs significantly inhibited (P<0.05) the seed vigor of water spinach, and the inhibitory effect increased with increasing concentration of LDPE MPs. However, the 5% LDPE MPs significantly promoted the aboveground biomass of water spinach. The 0.2% and 10% LDPE MPs significantly improved the superoxide dismutase (SOD) activity and catalase (CAT) and peroxidase (POD) activities, respectively. Further, malondialdehyde (MDA) content decreased with increasing concentration of LDPE MPs, and the reductions reached 15.53%-27.39% in comparison to that in the control. The LDPE MPs also significantly increased the soluble sugar content of water spinach leaves. In summary, LDPE MPs could inhibit the seed vigor and promote biomass accumulation in water spinach. Water spinach could relieve the oxidative stress caused by LDPE MPs by regulating antioxidant enzyme activity and soluble protein content. Therefore, this study may provide basic information for assessing the influences of microplastics on vegetables.

Alpha-tocopheryl polyethylene glycol succinate-emulsified poly(lactic-co-glycolic acid) nanoparticles for reversal of multidrug resistance in vitro.

Multidrug resistance (MDR) is one of the factors in the failure of anticancer chemotherapy. In order to enhance the anticancer effect of P-glycoprotein (P-gp) substrates, inhibition of the P-gp efflux pump on MDR cells is a good tactic. We designed novel multifunctional drug-loaded alpha-tocopheryl polyethylene glycol succinate (TPGS)/poly(lactic-co-glycolic acid) (PLGA) nanoparticles (TPGS/PLGA/SN-38 NPs; SN-38 is 7-ethyl-10-hydroxy-camptothecin), with TPGS-emulsified PLGA NPs as the carrier and modulator of the P-gp efflux pump and SN-38 as the model drug. TPGS/PLGA/SN-38 NPs were prepared using a modified solvent extraction/evaporation method. Physicochemical characterizations of TPGS/PLGA/SN-38 NPs were in conformity with the principle of nano-drug delivery systems (nDDSs), including a diameter of about 200 nm, excellent spherical particles with a smooth surface, narrow size distribution, appropriate surface charge, and successful drug-loading into the NPs. The cytotoxicity of TPGS/PLGA/SN-38 NPs to MDR cells was increased by 3.56 times compared with that of free SN-38. Based on an intracellular accumulation study relative to the time-dependent uptake and efflux inhibition, we suggest novel mechanisms of MDR reversal of TPGS/PLGA NPs. Firstly, TPGS/PLGA/SN-38 NPs improved the uptake of the loaded drug by clathrin-mediated endocytosis in the form of unbroken NPs. Simultaneously, intracellular NPs escaped the recognition of P-gp by MDR cells. After SN-38 was released from TPGS/PLGA/SN-38 NPs in MDR cells, TPGS or/and PLGA may modulate the efflux microenvironment of the P-gp pump, such as mitochondria and the P-gp domain with an ATP-binding site. Finally, the controlled-release drug entered the nucleus of the MDR cell to induce cytotoxicity. The present study showed that TPGS-emulsified PLGA NPs could be functional carriers in nDDS for anticancer drugs that are also P-gp substrates. More importantly, to enhance the therapeutic effect of P-gp substrates, this work might provide a new insight into the design of pharmacologically inactive excipients that can serve as P-gp modulators instead of drugs that are P-gp inhibitors.

Rapamycin Liposomes Combined with 5-Fluorouracil Inhibits Angiogenesis and Tumor Growth of APC (Min/+) Mice and AOM/DSS-Induced Colorectal Cancer Mice.

Background: Transgenic C57BL/6-APC(Min/+) spontaneous cancer mouse model and the Azoxymethane (AOM)/Dextran Sulfate Sodium (DSS) chemically induced orthotopic colorectal cancer mouse model represented distinct pathogenesis of colorectal cancers. Our previous study revealed that the combination of Rapamycin liposomes (Rapa/Lps) and 5-Fluorouracil (5-FU) has anti-colorectal cancer effects. However, the therapeutic efficacy of Rapa/Lps and 5-FU in other colorectal cancer mice models is yet to be thoroughly explored. The purpose of this study was to investigate the anti-tumor effect of Rapa/Lps combined with 5-FU in vivo and in vitro. Methods: In this study, we evaluated the effect of Rapa/Lps and 5-FU on APC (Min/+) mice and AOM/DSS-induced colorectal cancer mice. The small intestine, colorectum, serum, and plasma of mice in each group were collected following sacrifice to record the number of tumors. HE staining was utilized for observing pathological damage to intestine tissues. Tube formation assay, Transwell assay, wound healing assay, Western Blot were used to explore the anti-angiogenesis effect of drugs in HUVECs. Results: As expected, Rapa/Lps and 5-FU significantly suppressed tumor formation, decreased the number of tumors, and tumor load both in two mouse models, and had no influence on mouse weight. Mechanically, the anti-tumor effect of the drug also was associated in inhibiting angiogenesis and proliferation. Furthermore, we found that Rapa/Lps obviously inhibited HUVECs tube formation and migration. Conclusion: Altogether, we revealed the Rapa/Lps synergism with 5-FU decreased colon and small intestinal tumorigenesis in AOM/DSS-treated and APC (Min/+) mice, respectively, and correlated with anti-angiogenesis.

Enhancing electro-transformation competency of recalcitrant Bacillus amyloliquefaciens by combining cell-wall weakening and cell-membrane fluidity disturbing.

Bacillus amyloliquefaciens has been a major workhorse for the production of a variety of commercially important enzymes and metabolites for the past decades. Some subspecies of this bacterium are recalcitrant to exogenous DNA, and transformation with plasmid DNA is usually less efficient, thereby limiting the genetic manipulation of the recalcitrant species. In this work, a methodology based on electro-transformation has been developed, in which the cells were grown in a semicomplex hypertonic medium, cell walls were weakened by adding glycine (Gly) and DL-threonine (DL-Thr), and the cell-membrane fluidity was elevated by supplementing Tween 80. After optimization of the cell-loosening recipe by response surface methodology (RSM), the transformation efficiency reached 1.13 ± 0.34 × 10(7) cfu/µg syngeneic pUB110 DNA in a low conductivity electroporation buffer. Moreover, by temporary heat inactivation of the host restriction enzyme, a transformation efficiency of 8.94 ± 0.77 × 10(5) cfu/µg DNA was achieved with xenogeneic shuttle plasmids, a 10(3)-fold increase compared to that reported previously. The optimized protocol was also applicable to other recalcitrant B. amyloliquefaciens strains used in this study. This work could shed light on the functional genomics and subsequent strain improvement of the recalcitrant Bacillus, which are difficult to be transformed using conventional methods.

One-pot tuning of Au nucleation and growth: from nanoclusters to nanoparticles.

We describe a simple and effective method to obtain colloidal surface-functionalized Au nanoparticles. The method is primarily based on irradiation of a gold solution with high-flux X-rays from a synchrotron source in the presence of 11-mercaptoundecanoic acid (MUA). Extensive tests of the products demonstrated high colloidal density as well as excellent stability, shelf life, and biocompatibility. Specific tests with X-ray diffraction, UV-visible spectrometry, visible microscopy, Fourier transform infrared spectroscopy, dark-field visible-light scattering microscopy, and transmission electron microscopy demonstrated that MUA, being an effective surfactant, not only allows tunable size control of the nanoparticles, but also facilitates functionalization. The nanoparticle sizes were 6.45 ± 1.58, 1.83 ± 1.21, 1.52 ± 0.37 and 1.18 ± 0.26 nm with no MUA and with MUA-to-Au ratios of 1:2, 1:1, and 3:1. The MUA additionally enabled functionalization with l-glycine. We thus demonstrated flexibility in controlling the nanoparticle size over a large range with narrow size distribution.

Preliminary characterization of the oral microbiota of Chinese adults with and without gingivitis.

BACKGROUND: Microbial communities inhabiting human mouth are associated with oral health and disease. Previous studies have indicated the general prevalence of adult gingivitis in China to be high. The aim of this study was to characterize in depth the oral microbiota of Chinese adults with or without gingivitis, by defining the microbial phylogenetic diversity and community-structure using highly paralleled pyrosequencing. METHODS: Six non-smoking Chinese, three with and three without gingivitis (age range 21-39 years, 4 females and 2 males) were enrolled in the present cross-sectional study. Gingival parameters of inflammation and bleeding on probing were characterized by a clinician using the Mazza Gingival Index (MGI). Plaque (sampled separately from four different oral sites) and salivary samples were obtained from each subject. Sequences and relative abundance of the bacterial 16 S rDNA PCR-amplicons were determined via pyrosequencing that produced 400 bp-long reads. The sequence data were analyzed via a computational pipeline customized for human oral microbiome analyses. Furthermore, the relative abundances of selected microbial groups were validated using quantitative PCR. RESULTS: The oral microbiomes from gingivitis and healthy subjects could be distinguished based on the distinct community structures of plaque microbiomes, but not the salivary microbiomes. Contributions of community members to community structure divergence were statistically accessed at the phylum, genus and species-like levels. Eight predominant taxa were found associated with gingivitis: TM7, Leptotrichia, Selenomonas, Streptococcus, Veillonella, Prevotella, Lautropia, and Haemophilus. Furthermore, 98 species-level OTUs were identified to be gingivitis-associated, which provided microbial features of gingivitis at a species resolution. Finally, for the two selected genera Streptococcus and Fusobacterium, Real-Time PCR based quantification of relative bacterial abundance validated the pyrosequencing-based results. CONCLUSIONS: This methods study suggests that oral samples from this patient population of gingivitis can be characterized via plaque microbiome by pyrosequencing the 16 S rDNA genes. Further studies that characterize serial samples from subjects (longitudinal study design) with a larger population size may provide insight into the temporal and ecological features of oral microbial communities in clinically-defined states of gingivitis.

Synthesis, Antifungal Activity, and Cytotoxicity of AgBr-NP@CTMAB Hybrid and Its Application in PMMA.

OBJECTIVE: To synthesize and determine the antifungal activity of AgBr-nanoparticles (NP) @CTMAB (cetyltrimethyl-ammonium bromide) against Candida albicans (C. albicans) for use in the field of denture cleaning. METHODS: The morphology and structure of AgBr-NP@CTMAB were characterized by IR, UV-Vis, XRD and SEM. The antifungal potential of AgBr-NP@CTMAB against C. albicans was determined by colony formation assay and growth curve analysis. PMMA containing AgBr-NP@CTMAB was prepared, and the long-term antifungal efficacy was analyzed. The effect against C. albicans biofilm was analyzed by SEM and OD600 , and the color changes of the specimens were observed by stereomicroscopy after 1 week of incubation. Cytotoxicity to human oral gingival fibroblasts and oral mucosal epithelial cells was detected by Cell Counting Kit-8 (CCK-8) in vitro. RESULTS: The compound showed a good crystalline phase, the presence of AgBr nanoparticles and the hybridization of CTMAB+ with AgBr-NPs. AgBr-NP@CTMAB showed significant antifungal activity against C. albicans at concentrations of 10 µg/mL and 20 µg/mL. PMMA specimens containing AgBr-NP@CTMAB showed no long-term antifungal effect against C. albicans biofilm. The clearance rate of C. albicans attached to PMMA was 44.73% after soaking in 10 µg/mL AgBr-NP@CTMAB solution for 30 min and 91.35% for 8 h. There was no significant residual cytotoxicity or visual color change after soaking. SIGNIFICANCE: AgBr-NP@CTMAB showed promising potential treatment for denture cleaners.

Delivery of Rapamycin by Liposomes Synergistically Enhances the Chemotherapy Effect of 5-Fluorouracil on Colorectal Cancer.

BACKGROUND: Rapamycin is a promising agent for treating tumors, but clinical applications of rapamycin are limited due to its poor water solubility and low bioavailability. This paper constructs a liposome delivery system for rapamycin to improve the effect in treating colorectal cancer. METHODS: We prepared the rapamycin liposomes using the ethanol injection method. The cellular uptake and biodistribution were detected by LC-MS and in vivo imaging system. MTT assay, transwell migration experiment, flow cytometry, and Western blot analysis evaluated the antitumor effect of rapamycin liposomes in vitro. Furthermore, HCT-116 tumor-bearing mice were used to assess the therapeutic efficacy of rapamycin liposomes in vivo. RESULTS: The prepared rapamycin liposomes had a particle size of 100±5.5 nm and with a narrow size distribution. In vitro cellular uptake experiments showed that the uptake of rapamycin liposomes by colorectal cells was higher than that of free rapamycin. Subsequently, in vivo imaging experiments also demonstrated that rapamycin liposomes exhibited higher tumor accumulation. Therefore, the ability of rapamycin liposomes to inhibit tumor proliferation, migration and to induce tumor apoptosis is superior to that of free rapamycin. We also demonstrated in vivo good antitumor efficacy of the rapamycin liposomes in HCT-116 xenograft mice. In addition, rapamycin liposomes and 5-FU can synergistically improve the efficacy of colorectal cancer via the Akt/mTOR and P53 pathways. CONCLUSION: Collectively, rapamycin liposomes are a potential treatment for colorectal cancer, as it not only improves rapamycin's antitumor effect but also synergistically enhances 5-FU's chemotherapy effect.