Monodisperse Au-Fe2C Janus Nanoparticles: An Attractive Multifunctional Material for Triple-Modal Imaging-Guided Tumor Photothermal Therapy.

Imaging-guided photothermal therapy (PTT) by combination of imaging and PTT has been emerging as a promising therapeutic method for precision therapy. However, the development of multicomponent nanoplatforms with stable structures for both PTT and multiple-model imaging remains a great challenge. Herein, we synthesized monodisperse Au-Fe2C Janus nanoparticles (JNPs) of 12 nm, which are multifunctional entities for cancer theranostics. Due to the broad absorption in the near-infrared range, Au-Fe2C JNPs showed a significant photothermal effect with a 30.2% calculated photothermal transduction efficiency under 808 nm laser irradiation in vitro. Owing to their excellent optical and magnetic properties, Au-Fe2C JNPs were demonstrated to be advantageous agents for triple-modal magnetic resonance imaging (MRI)/multispectral photoacoustic tomography (MSOT)/computed tomography (CT) both in vitro and in vivo. We found that Au-Fe2C JNPs conjugated with the affibody (Au-Fe2C-ZHER2:342) have more accumulation and deeper penetration in tumor sites than nontargeting JNPs (Au-Fe2C-PEG) in vivo. Meanwhile, our results verified that Au-Fe2C-ZHER2:342 JNPs can selectively target tumor cells with low cytotoxicity and ablate tumor tissues effectively in a mouse model. In summary, monodisperse Au-Fe2C JNPs, used as a multifunctional nanoplatform, allow the combination of multiple-model imaging techniques and high therapeutic efficacy and have great potential for precision theranostic nanomedicines.

Integrating oxaliplatin with highly luminescent carbon dots: an unprecedented theranostic agent for personalized medicine.

A theranostic nanomedicine (CD-Oxa) is synthesized by means of the condensation reaction between the amino groups on the surface of fluorescent carbon dots (CDs) and the carboxyl group of the oxaliplatin derivative Oxa(IV)-COOH. CD-Oxa, which integrates the optical properties of CDs and the anticancer function of oxaliplatin, could be used for simultaneous drug delivery and fluorescent tracking.

Multifunctional Fe5 C2 nanoparticles: a targeted theranostic platform for magnetic resonance imaging and photoacoustic tomography-guided photothermal therapy.

Fe5 C2 NPs exhibit a high contrast in magnetic resonance imaging (MRI), superior photoacoustic tomography improvements, and efficient photothermal therapy (PTT) due to their unique core/shell structure, with a magnetic core and carbon shell. By conjugating a new class of affinity proteins (ZHER2:342), they can target to tumor cells with low cytotoxicity, and kill them through laser irritation. It is also possible to ablate tumors under guidance by MRI and PTT without noticeable side effects.

Microabrasion: a treatment option for white spots.

The aim of the present study was to describe a clinical protocol for the treatment of white spots with the use of an abrasive material. A four-year-old patient presented with a white spot on tooth 51 and a white spot associated with a carious lesion in the cervical region of tooth 52. Treatment was planned with microabrasion and restoration of the upper right lateral incisor. Prophylaxis was first performed, followed by protection with a dental dam and the application of the abrasive material (silicon carbide and hydrochloric acid 6%). Five applications were needed to remove the spots. The restoration of the upper right lateral incisor was then performed with a resin composite. A good esthetic outcome was achieved and both the patient and her guardians were satisfied with the results. Microabrasion is a conservative treatment option that achieves satisfactory results with regard to tooth color.

[Justifying measures to correct functional state of operators varying in personal anxiety].

Workers of operating and dispatching occupations are exposed to high nervous and emotional exertion that result in increased personal anxiety, working stress and overstrain. That requires physiologically justified correction of hazardous psycho-physiologic states via various prophylactic measures (stay in schungite room, autogenous training, central electric analgesia, electric acupuncture). Attempted relaxation sessions in schungite room revealed in highly anxious individuals an increased velocity of visual signals perception, of attention concentration and shifting. Autogenous training sessions improve memory and have significant hypotensive effect in highly anxious individuals.

A minimally invasive procedure for esthetic achievement: enamel microabrasion of fluorosis stains.

Esthetic alterations (such as fluorosis) that result from intrinsic dental staining in enamel and dentin can be controlled or softened by noninvasive methods such as dental bleaching or enamel microabrasion. Part of the enamel is removed during microabrasion; however, this wear is clinically insignificant and does not harm the dental structure. This article presents a case in which the microabrasion technique was used to remove fluorosis staining. Based on the results of this case report, it can be concluded that this technique is efficient and can be considered a minimally invasive procedure.

Cytocompatibility of bio-inspired silicon carbide ceramics.

Due to its good mechanical and biochemical properties and, also, because of its unique interconnected porosity, bio-inspired silicon carbide (bioSiC) can be considered as a promising material for biomedical applications, including controlled drug delivery devices and tissue engineering scaffolds. This innovative material is produced by molten-Si infiltration of carbon templates, obtained by controlled pyrolysis of vegetable precursors. The final SiC ceramic presents a porous-interconnected microstructure that mimics the natural hierarchical structure of bone tissue and allows the internal growth of tissue, as well as favors angiogenesis. In the present work, the in vitro cytocompatibility of the bio-inspired SiC ceramics obtained, in this case, from the tree sapelli (Entandrophragma cylindricum) was evaluated. The attachment, spreading, cytoskeleton organization, proliferation, and mineralization of the preosteoblastic cell line MC3T3-E1 were analyzed for up to 28 days of incubation by scanning electron microscopy, interferometric profilometry, confocal laser scanning microscopy, MTT assay, as well as red alizarin staining and quantification. Cells seeded onto these ceramics were able to attach, spread, and proliferate properly with the maintenance of the typical preosteoblastic morphology throughout the time of culture. A certain level of mineralization on the surface of the sapelli-based SiC ceramics is observed. These results demonstrated the cytocompatibility of this porous and hierarchical material.

Considerations about enamel microabrasion after 18 years.

PURPOSE: To review of the current status of enamel microabrasion method and its results 18 years after the development and application of this method. METHODS: A technique performing enamel microabrasion with hydrochloric acid mixed with pumice and other techniques employing a commercially available compound of hydrochloric acid and fine-grit silicon carbide particles in a water-soluble paste have been described. Much has been learned about the application of this esthetic technique, long-term treatment results and microscopic changes to the enamel surface that has significant clinical implications. The latest treatment protocol is presented and photographic case histories document the treatment results. Clinical observations made over 18 years are discussed. RESULTS: According to our findings, the dental enamel microabrasion technique is a highly satisfactory, safe and effective procedure.

Conservative aesthetic techniques for discoloured teeth: 2. Microabrasion and composite.

UNLABELLED: The first article in this series discussed the minimal intervention approach to discoloured teeth, starting with dental bleaching. This second article goes on to explain the technique of microabrasion and the use of direct composite techniques. CLINICAL RELEVANCE: Microabrasion and composite can provide minimally invasive treatments for discoloured teeth.

Micro/nanoscale mechanical and tribological characterization of SiC for orthopedic applications.

Micro/nanomechanical and tribological characterization of SiC has been carried out. For comparison, measurements on SiC, CoCrMo, Ti-6Al-4V, and stainless steel have also been made. Hardness and elastic modulus of these materials were measured by nanoindentation using a nanoindenter. The nanoindentation impressions were imaged using an atomic force microscope (AFM). Scratch, friction, and wear properties were measured using an accelerated microtribometer. Scratch and wear damages were studied using a scanning electron microscope (SEM). It is found that SiC exhibits higher hardness, elastic modulus, scratch resistance as well as lower friction with fewer and smaller debris particles compared to other materials. These results show that SiC possesses superior mechanical and tribological properties that make it an ideal material for use in orthopedic and other biomedical applications.

Estudo prospectivo e randomizado de pacientes tratados com e sem stents revestidos com carbeto de silício amorfo para a prevenção da reestenose coronariana. Avaliação ultra-sonográfica / Randomized intravascular ultrasound comparison between endoprostheses with and without amorphous silicon-carbide

OBJETIVO: A reestenose intra-stent é a maior limitação das intervenções coronárias percutâneas. O carbeto de silício amorfo (SiC-a), substância antitrombótica e antiinflamatória capaz de reduzir a deposição de fibrina, plaquetas e leucócitos sobre o stent, apresenta potencial de prevenir a hiperplasia neo-intimal e a reestenose. MÉTODOS: Estudo prospectivo, randomizado e tipo rótulo aberto comparando pacientes com doença coronariana tratados com e sem stents revestidos com o SiC-a, utilizando a angiografia quantitativa e o ultra-som intracoronário. Foram incluídos 100 pacientes (50 em cada grupo) a fim de mensurar o volume de hiperplasia neo-intimal intra-stent/extremidades. Como os stents comparados apresentavam extensões diferentes, o volume de hiperplasia foi analisado em valores absolutos (por paciente) e relativos (por milímetro de extensão do stent). Avaliaram-se ainda os eventos cardíacos maiores e os resultados da angiografia quantitativa. RESULTADOS: Os grupos apresentaram características de base semelhantes. Todos os pacientes foram tratados com sucesso. No 6° mês de evolução foram reestudados 94 por cento dos casos dos dois grupos, obtendo-se ultra-som em 92 por cento. O volume de hiperplasia neo-intimal absoluto foi significativamente maior nos tratados com os stents revestidos (51.2 DP 18.8 mm³ vs 41.9 DP 16.4 mm³; p=0.014), porém o relativo foi semelhante (2.9 DP 1.0 mm³/mm stent vs 2.5 DP 0.9 mm³/mm stent; p=0.108). A obstrução volumétrica da luz também foi similar (36.4 DP 11.1 por cento vs 37.9 DP 10.9 por cento; p=0.505). O diâmetro mínimo da luz (1.9 DP 0.7 mm vs 1.8 DO 0.6 mm; p=0.552), a reestenose (19.1 por cento vs 17 por cento; p>0.999) e a revascularização do vaso-alvo (16 por cento vs 14 por cento; p>0.999) não diferiram. CONCLUSÃO: Os stents revestidos apresentaram resultados clínicos, angiográficos e ultra-sonográficos similares aos controles.

Using microabrasive material to remove fluorosis stains.

BACKGROUND: Increased public access to fluoride has decreased the prevalence of caries and increased the prevalence of fluorosis staining. This article provides a case report involving a conservative method of removing fluorosis stain, as well as describes an in vitro test of the method. CASE DESCRIPTION: A healthy man sought treatment at New York University College of Dentistry for removal of severe, dark brown fluorosis staining on his anterior teeth. To remove the stain, the treating clinician used a microabrasive material, which leaves enamel intact, instead of a tooth-whitening agent, which requires removal of all affected enamel. METHODS: To demonstrate that enamel structure is not disturbed by the microabrasive material, the authors performed a study using scanning electron microscopy, or SEM. They viewed enamel structure under SEM at x1,000 magnification. They viewed untreated microabraded enamel and compared it with enamel that had been treated for 20 seconds with 37 percent phosphoric acid. RESULTS: An etch pattern was not discernible on the tooth treated with the microabrasive material. The enamel prisms remained intact and the cores were not exposed. CLINICAL IMPLICATIONS: Microabrasion removes intrinsic fluorosis stain effectively while protecting enamel. In this case, an enamel shade of brown not in the range of any tooth color shade guide was reduced.

[Development of new biologically active dressings and methodology of their use]. / Razrabotka novykh biologicheski aktivnykh pereviazochnykh sredstv i metodologiia ikh primeneniia.

Results of development of new biologically active dressings and up-to-date methodology of local treatment of wounds (based on their differential application according to phase and features of wound process) are demonstrated. Data about main properties and specific activity of new biologically active dressings based on natural and synthetic polymers with immobilized drugs are presented. Future trends and efficacy of their appliance in complex treatment of purulent and necrotic wounds are demonstrated.

Silicon carbide-coated stents in patients with acute coronary syndrome.

Silicon carbide (aSIC-C) is a stent coating with antithrombogenic as well as anti-inflammatory properties as compared with uncoated stainless steal based on in vitro and in vivo studies. This study investigated the potential of this coating in patients with unstable angina. At 38 study sites, 485 patients were randomized to an aSIC-C (n = 238) or a conventional stainless steal stent (n = 247). Patient were classified according to angina at rest within last 48 hr to Braunwald in class IIB (= 314) and IIIB (n = 171). The primary endpoint was a combination of death, myocardial infarction, or ischemia-driven target vessel revascularization at 6 months. Complications of procedures performed at 0.4 +/- 1.1 days after admission occurred at lower rates than previously reported in this high-risk population, but the primary endpoint was not different between the study groups. Only in Braunwald class IIIB patients did the primary endpoint occur less frequently in patients with an aSIC-C stent as compared to patients with a conventional stent (5.8% vs. 15.3%; P = 0.049). At 9-month follow-up, the level of difference was maintained, but statistical significance was lost. Quantitative angiography revealed no significant difference between the stents in the subgroups. This study suggests that aSIC-C stents exert clinically measurable effects in patients with unstable angina with recent symptoms at rest. This coating deserves further clinical investigation and may serve as platform for antiproliferative drugs.

Esthetic improvement following enamel microabrasion on fluorotic teeth: a case report.

Enamel microabrasion is a proven method of removing intrinsic and superficial defects from teeth, establishing esthetics with minimal loss of dental enamel. This article reports one case in which two different microabrasion techniques were used to remove fluorotic stains from teeth.