Preparation of biomedical Ag incorporated hydroxyapatite/titania coatings on Ti6Al4V alloy by plasma electrolytic oxidation

Nano-Ag incorporated hydroxyapatite/titania （HA/TiO2） coatings were deposited on Ti6A14V substrates by the plasma electrolytic oxidation process. Compared with the substrate, the deposited coatings display attractive mechani- cal and biomedical properties. First, the coatings have stronger wear resistance and corrosion resistance. Second, they show a strong antibacterial ability. The mean vitality of the P. gingivalis on the coating surfaces is reduced to about 21%. Third, the coatings have good biocompatibility. The mean viability of the fibroblast cells on the coating surface is increased to about 130%. With these attractive properties, Ag incorporated HA/TiO2 coatings may be useful in the biomedical field.

Double Roots of Mandibular Premolar in Full-mouth Periapical Films

Objective To evaluate the incidence of two-rooted mandibular premolar morphology using full-mouth periapical film series in a Chinese population,with particular emphasis on bilateral incidence,so as to provide a clinical anatomical basis for root canal treatment in mandibular premolars.Methods A total of 2015 patients who underwent dental treatment and had full mouth periapical radiographs at the Peking University School of Stomatology from April 2011 to April 2012 were enrolled in this study.Three experienced dentists reviewed the patients' periapical films and classified the root morphology of mandibular premolars bilaterally.The incidence of unilateral and bilateral double roots were recorded and calculated,including confirmed and suspected bucco-lingual root types.Results In terms of the morphology of two-rooted mandibular first premolars,of the 2015 cases with complete root formation,two-rooted first premolars were detected in 120 cases,with a total number of 159 teeth.According to the number of teeth,the overall incidence of double roots was 4.03%(159/3972).In terms of the morphology of two-rooted mandibular second premolars,of the 2015 cases with complete root formation,two-rooted second premolars were detected in 24 cases,with a total number of 33 teeth.According to the number of teeth,the overall incidence of double roots was 0.85%(33/3880).Conclusions The roots of mandibular premolars display specific morphological patterns.Based on a large sample,we observed and calculated not only the occurrence rate of bucco-lingual and mesio-distal double roots in first and second mandibular premolars,but also the incidence of unilateral or bilateral double roots within the same mandible.These findings could provide useful information on the anatomical structure of mandibular premolars for endodontic,prosthodontic and surgical procedures,and could improve the quality of treatment and reduce complications.

A portable illumination device for photodynamic therapy of the oral cavity

Photodynamic therapy(PDT)is a minimally invasive method for treating oral leukoplakia In this paper,we propose a portable PDT device consisting of a flexible circuit board with a liquid flow cooling module on the back.The light source size was 17 mm×11 mm×4 mm,and the iradiation area of the light source was up to 100mm'.The iradiance range of this device was from 10mW/cm^(2)to 100mW/cm^(2).Simulation and experimental results showed that the irradiance cofficient variation for a treatment area of 81 mm was less than 7%.At an irradiance of 100 mW/cm a device surface temperature of lower than 42℃ can be achieved to satisfy the safety requirements under the con-ditions that the temperature of cooling liquid is 10℃ and the liquid flow speed is above 12 mL/min.

Sclerosing odontogenic carcinoma of maxilla:A case report

BACKGROUND Sclerosing odontogenic carcinoma is a rare primary intraosseous neoplasm that was featured recently as a single entity in the World Health Organization classification of Head and Neck Tumors 2017,with only 14 cases published to date.The biological characteristics of sclerosing odontogenic carcinoma remain indistinct because of its rarity;however,it appears to be locally aggressive,with no regional or distant metastasis reported to date.CASE SUMMARY We reported a case of sclerosing odontogenic carcinoma of the maxilla in a 62-year-old woman,who presented with an indolent right palatal swelling,which progressively increased in size over 7 years.Right subtotal maxillectomy with surgical margins of approximately 1.5 cm was performed.The patient remained disease free for 4 years following the ablation surgery.Diagnostic workups,treatment,and therapeutic outcomes were discussed.CONCLUSION More cases are needed to further characterize this entity,understand its biological behavior,and justify the treatment protocols.Resection with wide margins of approximately 1.0 to 1.5 cm is proposed,while neck dissection,post-operative radiotherapy,or chemotherapy are deemed unnecessary.

Excessive additive iodine intake reduces sperm production and induces sperm deformity in male rats in early development

Objective:To investigate the effect of excessive additive iodine intake on reproductive organs of male weanling rats. Methods:One hundred and three male weanling rats were fed with feedstuff containing 0,0.5.1.2.5,and 5- fold higher dosage of iodine in standard iodine-additive salt,i.e.200,300,400,700,and 1200μg/kg,respectively, for 130-136 days.The number of rats taking different dosages of iodine was 20,21,21,21,20 respectively.The rats fed 200μg/kg of iodine were taken as the control group.For all groups,their structural changes of reproductive organs and sperm quality were evaluated. Results:The three experiment groups fed with 1,2.5,and 5-fold higher dosage iodine showed apparent reduction in testicular weight(P<0.05-0.01) by 10.76%,14.58%and 25.35%,respectively,compared with the control. But significant reduction in testis/body weight ratio was only observed in the 5-fold higher dosage group.The sperm concentration and total sperm count declined in four experiment groups fed with 0.5-5 fold higher dosage of iodine.The sperm concentration was reduced by 6.59%,22.53%,17.35%and 18.06%respectively.The percentage of sperm with normal and abnormal form significantly changed(P<0.05).The addition of different doses of iodine showed no apparent adverse effects on other reproductive organs or sperm viability. Conclution:These results indicated that excessive iodine intake might cause potential hazards on reproductive organs of male rats with respect to spermatogenesis.

Myoepithelial carcinoma of the salivary glands: behavior and management

To investigate the biological behavior and proper management of myoepithelial carcinomas of salivary glands Methods Twenty seven cases of myoepithelial carcinoma of salivary glands were retrospectively studied and their detailed clinical and follow up data were presented Results The subjects consisted of 17 men and 10 women aged 16 to 73 years (mean age: 51 years) The parotid gland was the most common site (n=14) of cancer Clinical features included extensive local growth, invasion of the surrounding tissues, infrequent cervical lymph node metastasis but high rates of distant metastasis, frequent/multiple recurrences and poor prognosis Conclusions Myoepithelial carcinomas of the salivary gland should be classified as high grade malignancies Early and radical surgery with close follow up are essential for achieving favorable outcomes Radiotherapy appears to be non sensitive and elective neck dissection is generally unnecessary

Anatomy of arteries and veins of submandibular glands

Background Transplanting a vascularized autologous submandibular gland （SMG） is considered an effective method to treat severe keratoconjunctivitis sicca. But the operation may fail due to the anatomic variances in the blood vessels of SMG. The present study aimed to investigate the submandibular glands at the microanatomy level. Methods The microanatomy of blood vessels including arteries and veins of submandibular gland was investigated using 30 adult corpses and 60 submandibular glands were anatomized under a surgical microscope. The lengths and diameters of the arterial and venous glandular branches were measured using sliding caliper. Results The submandibular gland was mainly supplied by the facial artery and submental artery, partly by the lingual artery and external jugular artery. The venous drainage of the submandibualr gland occurred through the anterior facial vein, the venae comitantes of facial artery, the vein close to the Whaston＇s duct （the hilum vein）, and seldom drained to external jugular vein and other veins. Conclusions The anatomy of SMG is a complicated structure. Determining the main blood vessels of the submandibular gland is very important to achieve a successful vascularized autologous SMG transplant.

Promoting musculoskeletal system soft tissue regeneration by biomaterial-mediated modulation of macrophage polarization

Musculoskeletal disorders are common in clinical practice.Repairing critical-sized defects in musculoskeletal systems remains a challenge for researchers and surgeons,requiring the application of tissue engineering biomaterials.Successful application depends on the response of the host tissue to the biomaterial and specific healing process of each anatomical structure.The commonly-held view is that biomaterials should be biocompatible to minimize local host immune response.However,a growing number of studies have shown that active modulation of the immune cells,particularly macrophages,via biomaterials is an effective way to control immune response and promote tissue regeneration as well as biomaterial integration.Therefore,we critically review the role of macrophages in the repair of injured musculoskeletal system soft tissues,which have relatively poor regenerative capacities,as well as discuss further enhancement of target tissue regeneration via modulation of macrophage polarization by biomaterial-mediated immunomodulation(biomaterial properties and delivery systems).This active regulation approach rather than passive-evade strategy maximizes the potential of biomaterials to promote musculoskeletal system soft tissue regeneration and provides alternative therapeutic options for repairing critical-sized defects.

Effects of estradiol on proliferation and metabolism of rabbit mandibular condylar cartilage cells in vitro

Objective To investigate the effects in vitro of 17 β-estradiol (E2) on the proliferation and metabolism of rabbit mandibular condylar cartilage cells.Methods Chondrocytes were derived from neonatal rabbit mandibular condylar cartilage using a modified enzyme method. 17p-estradiol was added to the culture medium in a variety of concentrations. Cell growth and DNA, collagen, and proteoglycan synthesis were used as indicators of proliferation and differentiation of condylar chondrocytes. These were measured by cell number, 3H-proline and 35S-incorporation, respectively.Results E2 increased cell number and 3H-thymidine incorporation at 10^(-8) to 10^(-10)mol/L, and 10^(-8) to 10^(-11) mol/L in a dose-dependent manner, peaking at 10^(-8) mol/L and 10^(-9) mol/L, respectively. However, further increase in the concentration of estradiol caused inhibition of both cell number and 3H-thymidine incorporation, and this was significant at 10^(-6) mol/L. The effect of E2 on proteglycan synthesis was similar; the maximum stimulating effect was at 10^(-8) mol/L, and inhibition was significant at 10^(-6) mol/L. There was no obvious stimulatory effect of E2 on 3H-thymidine incorporation observed.Conclusions Estradiol affects condylar chondrocyte cell growth, DNA, and proteoglycan synthesis in a biphasic manner depending on its concentration. This indicates that estrogen may be important in the proliferation and differentiation of mandibular condylar chondrocytes, and could be relevant to some aspects of certain tempormandibular joint diseases by modulating the function of the chondrocytes.

Clinical follow-up of ceramic bridges with auro-galvanoforming primary coping and Ni-Cr pontic for restoration of dentition defects

Background Alternatives to the conventional auro-galvanoforming ceramic bridge need to be evaluated in long-term longitudinal studies before being recommended for restoration of dentition defects. This study aimed to evaluate the clinical performance of a ceramic bridge with auro-galvanoforming primary coping and Ni-Cr pontic for restoration of dentition defects. Methods In total, 114 ceramic bridges with auro-galvanoforming （primary coping and Ni-Cr pontic） were placed in 112 patients with dentition defects. Among them, 83 bridges in 82 patients were available for follow-up after 7 years. We evaluated marginal integrity, color match, gingival inflammation, fracture of ceramic bridges, and recurrent caries. Results Marginal integrity of the ceramic bridges was perfect in all patients. Most ceramic bridges maintained their original color. Fracture was found in three bridges; the rest were free of fracture, breakage, and loosening. Recurrent abutment caries were not found. Ceramic bridges with auro-galvanoforming （primary coping and Ni-Cr pontic） produced satisfactory clinical outcomes -- equivalent to the conventional porcelain-fused-to-metal restoration. This technique is especially useful for dentition defects of the molar area and is cheaper than restoration with noble metal bridges. Conclusions Ceramic bridges with auro-galvanoforming （primary coping and Ni-Cr pontic） performed well for the restoration of dentition defects during this follow-up period. More studies are warranted to further evaluate this technique as an alternative to the conventional porcelain-fused-to-metal restoration.

The role of genotype and diet in shaping gut microbiome in a genetic vitamin A deficient mouse model

Multifactors have been reported to affect the gut microbiome, including genotype, age, diet, and nutrition.However, few reports have investigated the relative capacity of different factors to shape the gut microbiome in a single study. Our design used a genetic vitamin A-deficient mouse model, the Rbp4^(-/-)mouse,feeding with the low vitamin A diets at different ages of initiation(4 or 7 weeks) for 28 days. Fecal samples were collected for bacterial profiling at seven time points after diet controlling. With Rbp4 depletion,Akkermansia decreased and Bacteroides increased, whereas Desulfovibrio, Barnesiella, Clostridium_Xl Va,and Lactobacillus fluctuated. The bacterial community swiftly adjusted with the vitamin A-deficient diet administration and gradually changed(e.g., decrease of Barnesiella and increase of Desulfovibrio). Age exerted a relatively weaker but long-last influence. At an earlier age to feed a vitamin A-deficient diet, a higher microbial dysbiosis index will be valued. Of note, the shaping effects of diet and age on the bacterial community varied with the difference of genotype, which might indicate a greater role of genotype than diet and age in shaping the gut microbiome.

Objective evaluation of cleft palate speech based on analyzing plosive consonants

An objective method, using a multi-band analysis technique, was proposed for analyzing plosive consonants in cleft palate speech. At first, the speech signal is decomposed in frequency domain using an auditory filter-bank. Then, the sample-based features, namely cumulative energy and its increment speed, in each band were computed. Finally, using principle component analysis, these features were fused into one combined feature vector for assessment. Since the algorithm is based on perceptual properties of human auditory ear using non-uniform and multi-band analysis, the improvements of the consistence between the proposed approach and subjective evaluation are obtained.

Aquaporin-1 and aquaporin-3 expressions in the temporo-mandibular joint condylar cartilage after an experimentally induced osteoarthritis

Background Over 70% of the total tissue weight in the cartilage matrix consists of water, and the early-stage osteoarthritic cartilage is characterized by swelling. Water transport in the cartilage matrix and across the membranes of chondrocytes may be important in normal and pathological conditions of cartilage. The purpose of this study was to identify aquaporin-1 （AQP1） and aquaporin-3 （AQP3） expressions in the mandibular condylar cartilage after experimentally induced osteoarthritis （OA） in rats. Methods An experimental temporomandibular joint OA was induced by partial discectomy in rats. The pathological characteristics of the normal, early-stage, and late-stage osteoarthritic TMJ cartilages were verified by histological techniques. The AQP1 and AQP3 gene expressions in the normal and osteoarthritic cartilages were measured using quantitative real-time reverse-transcription PCR analysis. The cartilage sections were incubated in primary polyclonal antibodies to AQP3; immunofluorescent microscopy was used to examine the AQP3 expression shown by its protein level. Results The mRNA expression levels of AQP1 and AQP3, analyzed using quantitative PCR, revealed that AQP3 mRNA was highly up-regulated in the OA cartilage, which was considered significant. There was no notable difference in the expression of AQP1 mRNA between OA and normal controls. With the progressing of the OA, the localization of the AQP3 protein was quite different from that of the normal cartilage. Compared to the normal cartilage, the expressions of AQP3 protein were observed mainly in the proliferative zone and the upper mid-zone chondrocytes at the early-stage of OA, and were observed to appear frequently throughout the mid- and deep zone during the late-stage of OA. Conclusions The high expression of AQP3 mRNA in the OA cartilage and the different localization of the AQP3 protein suggest that it may play a particular role in OA pathogenesis. Further study of AQP3 function may provide new insight into the understanding of the molecular mechanisms underlying OA.

Biomimetic strategies for tendon/ligament-to-bone interface regeneration

Tendon/ligament-to-bone healing poses a formidable clinical challenge due to the complex structure,composition,cell population and mechanics of the interface.With rapid advances in tissue engineering,a variety of strategies including advanced biomaterials,bioactive growth factors and multiple stem cell lineages have been developed to facilitate the healing of this tissue interface.Given the important role of structure-function relationship,the review begins with a brief description of enthesis structure and composition.Next,the biomimetic biomaterials including decellularized extracellular matrix scaffolds and synthetic-/natural-origin scaffolds are critically examined.Then,the key roles of the combination,concentration and location of various growth factors in biomimetic application are emphasized.After that,the various stem cell sources and culture systems are described.At last,we discuss unmet needs and existing challenges in the ideal strategies for tendon/ligament-to-bone regeneration and highlight emerging strategies in the field.

Large-area chemical vapor deposition-grown monolayer graphene-wrapped silver nanowires for broad-spectrum and robust antimicrobial coating

New types of antimicrobial systems are urgently needed owing to the emergence of pathogenic microbial strains that gain resistance to antibiotics commonly used in daily life and medical care. In this study we developed for the first time a broad-spectrum and robust antimicrobial thin film coating based on large-area chemical vapor deposition （CVD）-grown graphene-wrapped silver nanowires （AgNWs）. The antimicrobial graphene/AgNW hybrid coating can be applied on commerdal flexible transparent ethylene vinyl acetate/polyethylene terephthalate （EVA/PET） plastic films by a full roll-to-roll process. The graphene/AgNW hybrid coating showed broad-spectrum antimicrobial activity against Gram-negative （Escherichia coli） and Gram-positive bacteria （Staphylococcus aureus）, and fungi （Candida albicans）. This effect was attributed to a weaker microbial attachment to the ultra-smooth graphene film and the sterilization capacity of Ag＋, which is sustainably released from the AgNWs and presumably enhanced by the electrochemical corrosion of AgNWs. Moreover, the robust antimicrobial activity of the graphene/AgNW coating was reinforced by AgNW encapsulation by graphene. Furthermore, the antimicrobial efficiency could be enhanced to -100% by water electrolysis by using the conductive graphene/AgNW coating as a cathode. We developed a transparent and flexible antimicrobial cover made of graphene/AgNW/EVA/PET and an antimicrobial denture coated by graphene/ AgNW, to show the potential applications of the antimicrobial materials.

miR-29b upregulates miR-195 by targeting DNMT3B in tongue squamous cell carcinoma

MicroRNAs play important roles in the devel- opment and progression of various cancers, including tongue squamous cell carcinoma （TSCC）. miR-29b and miR-195 have been reported to be tumor suppressors in TSCC. Here, we investigated the expression of miR-29b and miR- 195 and their relationship in TSCC. Our data showed that miR-29b and miR-195 were significantly downregulated in TSCC com- pared with their matched nonmalignant tissues in 60 paired samples. The level of miR-29b was positively correlated with that of miR-195 in TSCC and the matched nonmalignant tissues. Moreover, miR-29b overexpression induced the demethylation of CpG islands upstream of miR-195 via targeting DNMT3B, leading to the upregulation of miR-195 in TSCC cell lines. Following DNMT3B silencing, the expression of miR-195 was increased and the methylation of CpG islands upstream of miR-195 was reduced. Although overexpression of miR-29b alone significantly increased miR- 195 expression, co-transfection of miR-29b with DNMT3B resulted in no change in miR-195 expression. Taken together, our results demonstrated that miR-29b could upregulate miR- 195 by directly targeting DNMT3B in TSCC. The interaction between miR-29b and miR-195 might provide new insights in developing novel therapeutic approaches of TSCC.

Nanosecond pulsed electric fields prime mesenchymal stem cells to peptide ghrelin and enhance chondrogenesis and osteochondral defect repair in vivo

Mesenchymal stem cells(MSCs) are important cell sources in cartilage tissue development and homeostasis,and multiple strategies have been developed to improve MSCs chondrogenic differentiation with an aim of promoting cartilage regeneration.Here we report the effects of combining nanosecond pulsed electric fields(ns PEFs) followed by treatment with ghrelin(a hormone that stimulates release of growth hormone) to regulate chondrogenesis of MSCs.ns PEFs and ghrelin were observed to separately enhance the chondrogenesis of MSCs,and the effects were significantly enhanced when the bioelectric stimulation and hormone were combined,which in turn improved osteochondral tissue repair of these cells within Sprague Dawley rats.We further found that ns PEFs can prime MSCs to be more receptive to subsequent stimuli of differentiation by upregulated Oct4/Nanog and activated JNK signaling pathway.Ghrelin initiated chondrogenic differentiation by activation of ERK1/2 signaling pathway,and RNA-seq results indicated 243 genes were regulated,and JAK-STAT signaling pathway was involved.Interestingly,the sequential order of applying these two stimuli is critical,with ns PEFs pretreatment followed by ghrelin enhanced chondrogenesis of MSCs in vitro and subsequent cartilage regeneration in vivo,but not vice versa.This synergistic prochondrogenic effects provide us new insights and strategies for future cell-based therapies.