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BACKGROUND Odontogenic infection is one of the common infectious diseases in oral and maxillofacial head and neck regions. Clinically, if early odontogenic infections such as acute periapical periodontitis, alveolar abscess, and pericoronitis of wisdom teeth are not treated timely, effectively and correctly, the infected tissue may spread up to the skull and brain, down to the thoracic cavity, abdominal cavity and other areas through the natural potential fascial space in the oral and maxillofacial head and neck. Severe multi-space infections are formed and can eventually lead to life-threatening complications (LTCs), such as intracranial infection, pleural effusion, empyema, sepsis and even death. CASE SUMMARY We report a rare case of death in a 41-year-old man with severe odontogenic multi-space infections in the oral and maxillofacial head and neck regions. One week before admission, due to pain in the right lower posterior teeth, the patient placed a cigarette butt dipped in the pesticide "Miehailin" into the "dental cavity" to relieve the pain. Within a week, the infection gradually spread bilaterally to the floor of the mouth, submandibular space, neck, chest, waist, back, temporal and other areas. The patient had difficulty breathing, swallowing and eating, and was transferred to our hospital as an emergency admission. Following admission, oral and maxillofacial surgeons immediately organized consultations with doctors in otolaryngology, thoracic surgery, general surgery, hematology, anesthesia and the intensive care unit to assist with treatment. The patient was treated with the highest level of antibiotics (vancomycin) and extensive abscess incision and drainage in the oral, maxillofacial, head and neck, chest and back regions. Unfortunately, the patient died of septic shock and multiple organ failure on the third day after admission. CONCLUSION Odontogenic infection can cause serious multi-space infections in the oral and maxillofacial head and neck regions, which can result in multiple LTCs. The management and treatment of LTCs such as multi-space infections should be multidisciplinary led by oral and maxillofacial surgeons.

PURPOSE To compare the clinical efficacy of disposable multifunctional drainage tube (DMDT)-assisted irrigation with the traditional abscess incision rubber drainage technique in patients with severe multi-space infections in oral and maxillofacial head and neck regions. PATIENTS AND METHODS The data of 74 patients with severe multi-space infections in oral and maxillofacial head and neck regions, who were admitted to the Department of Oral and Maxillofacial Surgery, Central Hospital of Panzhihua City, Sichuan Province, China, between January 2015 and January 2019, were retrospectively studied. According to the treatment method, the patients were divided into 2 groups: the DMDT-assisted irrigation group and the abscess incision rubber drainage group. Cure rate, complications, length of hospitalization, days of antimicrobial use, cost of antimicrobial drugs, total hospitalization cost, number of dressing changes, and patient pain during dressing changes were compared between the 2 groups. RESULTS Of the 74 patients, 38 were treated with the DMDT-assisted irrigation, and 36 with the traditional abscess incision rubber drainage. Compared with the traditional treatment group, the total hospitalization cost of the DMDT-assisted irrigation group is not much different (P = 0.72), but the patients in the DMDT-assisted irrigation group have higher cure rate, fewer complications, less antibiotics cost, shorter hospitalization length and fewer dressing changes than the control group (P

A novel phenanthroline derivative, 4-[4-(N-methyl)styrene]-imidazo[4,5-f][1,10]phenanthroline-benzene iodated salt (MSIPBI), was synthesized, and the linear absorption and fluorescent spectra of MSIPBI in different solvents were investigated. The photophysical properties in unbound and in ligand-metal complexes were evaluated by UV absorption and one- and two-photon fluorescent spectra, and the quantum yields, two-photon active cross-sections and the binding constant of dye-metal were calculated. The results indicated that MSIPBI has a large Stokes shift (more than 167nm), and the dye was selective and sensitive for the detection of Hg(2+) with a two-photon active cross-section of 55.5GM in tris-HCl buffer solution at 800nm. Furthermore, the results of the fluorescence microscopy imaging indicated that MSIPBI is an efficient fluorescent probe for the detection of Hg(2+) in living cells by one- and two-photon excitation. Moreover, the experiments of determination Hg(2+) in river water and tap water were finished.

Most microvessels have been shown to become stenosed or completely occluded during hypertrophic scar progression. Here, we examined the morphology of capillary endothelial cells (ECs) and fibroblasts using immunofluorescence staining for CD31 and alpha-smooth muscle actin (α-SMA) and electron microscopy. In addition, ECs and fibroblasts were isolated from scar tissues, and the levels of transforming growth factor beta 1 (TGF-β1), platelet-derived growth factor (PDGF), endothelin 1 (ET-1), vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) were assayed using ELISAs. Furthermore, we assessed cell viability, total collagen production, and cell apoptosis in hypertrophic scar-derived fibroblasts cultured with EC-conditioned medium. Then, anti-TGF-β1, anti-PDGF, anti-ET-1, anti-VEGF, and anti-bFGF neutralising antibodies were individually added to the EC medium to identify which growth factor plays a more important role in inhibiting fibroblasts biology. Our results showed microvessel lumen occlusion and EC atrophy during scar development, particularly in regressive scars (RSs). Additionally, EC growth factor secretion decreased and reached the lowest levels in RSs. Furthermore, based on the culture results, RS EC medium inhibited fibroblast viability and collagen production and induced apoptosis. Moreover, TGF-β1, PDGF, and bFGF played more important roles in these processes than VEGF and ET-1. The endothelial dysfunction occurring in hypertrophic scars contributes to fibroblast inhibition and scar regression, and reduced TGF-β1, PDGF, and bFGF levels play key roles during this process.

A new biphenyl ethylene derivative, 4,4′-bis-(2-(4-N-ethyl-N-ethoxyl-amino) styryl] biphenyl (BEEASP) was successfully synthesized and studied as a potential fluorescent probe of DNA detection. The linear absorption and fluorescent spectra of the dye in different solvents were investigated. The absorption, one- and two-photon fluorescent spectra of the free dye and dye–DNA complex were also examined to evaluate their photophysical properties. The binding constant of dye–DNA was calculated with a moderate value. Two-photon active cross-sections (Фδ) were finished by the reference method, and the value at a stable complex of dye–DNA was about 37 GM. The experimental results showed that BEEASP can be used as an efficient fluorescent probe to detect DNA by single-photon excitation and two-photon excitation. The fluorescent method date indicated that the mechanism of dye–DNA complex interaction may be the groove binding.

Ag/PPy composites were prepared in β-naphthalene sulfonic acid (β-NSA) or sodium dodecyl sulfate (SDS) aqueous solutions with AgNO3 as oxidant. β-NSA or SDS acted as dopant and soft template in the process of preparing polypyrrole (PPy) by in situ oxidizing polymerization method. SEM, TEM, FTIR, XRD and Four-Point Probes Resistivity Measurement System were tested respectively and results indicated that the obtained Ag/PPy composites displayed different morphology,structure and conducting characteristic.

The band gap of a new two-dimensional phononic crystal was studied by the plane-wave expansion method. The two-dimensional phononic crystal is formed by square-shape array geometry of iron cylinders with square cross section inserted in an epoxy resin. The band gaps of different structures were calculated such as defect-free, single cavity crystal point defect states, crystal point defect states with (10) direction coupling, crystal point defect states with (10) direction next-nearest-neighbor coupling, and crystal point defect states with (11) direction next-nearest-neighbor coupling. Compared with that of defect-free, it is conclude that point defect is beneficial to the production of band gaps. The bandwidth of point defect is about 5 times larger than that of the defect-free crystal with the filling fraction F=0.4. In addition, the maximum number of band gap is in the crystal point defect states with (10) direction next-nearest-neighbor coupling. It will provide a theoretical reference for the manufacture of phononic crystal.

The band gap of 2D perfect and defect phononic crystal are calculated by using plane-wave expansion (PWE) and supercell plane wave method, which is consist of Al2O3 embedded in the epoxy resin with a square arrangement. Compared to the perfect, the gap of defect will become wider. As the size of defect length ld varied, the band structure changed. It is found that the acoustic wave only propagates along the path of defect when the propagation of acoustic wave is simulated on the 900 bending defect phononic crystals by matlab. It means that the waves are localized. So the defect mode of phononic crystal can be used as acoustic waveguide along the specific path.

Polypyrrole (PPy)-coated Cu nanocomposites were synthesized in aqueous solution at ambient temperature by situ polymerization of pyrrole. The morphology and structure of the nanoparticles had been studied by scanning and transmission electronic microscopes (TEM), X-ray diffractometer and Fourier Transform Infrared Spectroscopy (FTIR) and the results indicated the nanocomposites were core-shell structure. The electrical conductivity of nanocomposites was 0.0413 S/cm measured by four-probe technique.

Ultrawide ZnSe nanoribbons are synthesized by the simple thermal evaporation. The microstructure of ZnSe nanoribbons is characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), photoluminescence (PL) and Raman spectrum. It is found that the strong emission near the band gap of ZnSe centered at 460 nm is obtained in these nanoribbons. More importantly, ZnSe nanoribbons can act as lasing emitting optical cavities. Raman studies indicate that the longitudinal optic (LO) and transverse optic (TO) phonon confinements of the ZnSe nanoribbons shift to lower frequency.

Two new styryl heterocyclic two-photon (TP) materials, 4-[4-(N-methyl)styrene]-imidazo [4,5-f][1,10] phenanthroline-benzene iodated salt (probe-1) and 4,4-[4-(N-methyl)styrene]-benzene iodated salt (probe-2) were successfully synthesized and studied as potential fluorescent probes of DNA detection. The linear and nonlinear photophysical properties of two compounds in different solvents were investigated. The absorption, one- and two-photon fluorescent spectra of the free dye and dye-DNA complex were also examined to evaluate their photophysical properties. The binding constants of dye-DNA were obtained according to Scatchard equation with good values. The results showed that two probes could be used as fluorescent DNA probes by two-photon excitation, and TP fluorescent properties of probe-1 are superior to that of probe-2. The fluorescent method date indicated that the mechanisms of dye-DNA complex interaction may be groove binding for probe-1 and electrostatic interaction for probe-2, respectively. The MTT assay experiments showed two probes are low toxicity. Moreover, the TP fluorescence imaging of DNA detection in living cells at 800 nm indicated that the ability to locate in cell nuclei of probe-1 is better than that of probe-2.

Manganese oxide (hausmannite) nanowires were prepared by annealing precursor powders at a temperature of 800 °C for 3 h, which were produced in a novel inverse microemulsion (IμE) system. The microstructures of the as-prepared Mn3O4 nanowires were investigated by means of X-ray diffraction, transmission electron microscopy, and Raman spectra. It has been found that the Mn3O4 nanowires were relatively straight and their surfaces were smooth with a typical diameter of 75–150 nm. The formation mechanism of the Mn3O4 nanowires is discussed.

Mn-doped ZnS nanobelts have been prepared through a thermal evaporation method at 1100°C. The synthesized nanobelts are characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), selected area electron diffraction (SAED), high-resolution transmission electron microscopy (HRTEM), and photoluminescence (PL) spectroscopy. The results show that the nanobelts have an uniform single-crystal hexagonal wurtzite structure and grow along [0001] direction. Room-temperature photoluminescence reveals that the intrinsic PL of the nanobelts disappears and a new PL peak of the Mn-doped ZnS nanobelts emerges at 575 nm.

To explore the effect of focal-adhesion micromanipulation on the biological behavior of fibroblast.Micro-pot was made by microcontact printing. The molecules of constitutive protein was adhered on micro-pot by self-assemble of peptides. Skin fibroblasts were cultured on the membrane by self-made biomechanical cell culture for 2 weeks. Morphology observation and cell immunohistochemistry analysis was performed.After 2 weeks, the morphology of the fibroblasts was diverse and more compliant. Cell immunohistochemistry analysis found that the expression of integrinbeta1, alpha5 and tensin was dramatically reduced.The morphology and the biological behaviour of the fibroblasts in hypertrophic scar can be changed after micromanipulation of focal adhesion.

Scars are a common complication of surgery or burn wound management. Scars occur over the body, affecting people of both sexes and all ages. Scar therapy is a constant clinical challenge; antimitotic drugs and radiotherapy are used with varying degrees of success. This article examines the success of both these types of treatment modalities.

Although the etiology underlying scar formation is not well understood, previous studies revealed that endothelial cells play a role in the pathogenesis of scar development. Recently, the authors developed a reliable technique to obtain endothelial cells from hypertrophic scars that involved separation of cells from the scar tissue matrix and isolation from other cell types. Using phase-contract and electron microscopy, the cells were observed to have a characteristic morphology consistent with cells of endothelial origin. The cells were further characterized as endothelial cells by assessment of endothelin (ET)-1 and intercellular adhesion molecule (ICAM) mRNA expression, and the presence of factor VIII antigen, CD34, CD31, and VE-cadherin. This isolation method provides a simple method for culturing endothelial cells from hypertrophic scar tissue and should prove useful for studying the role of endothelial cell involvement in scar formation.

To explore the biological function of vascular endothelial cells from hypertrophic scar, and to analyze the relationship between them.The samples from human hypertrophic scar and normal skin tissue were harvested for histological examination. Then vascular endothelial cells were purified and isolated from the samples, and the level of transforming growth factor (TGF) beta1, platelet derived growth factor (PDGF), endothelin1 (ET)-1, fibroblast growth factor (FGF)2 and vascular endothelial growth factor (VEGF) were determined in a single cell with ELISA.Few capillary vessels were observed in normal skin under microscope, while an increased number of them were present in hypertrophic scar, with slender, tortuous in morphology and even occluded. The diameter of blood capillary in hypertrophic scar was tiny under electron microscope, and the exfoliation of endothelial cells was observed. The levels of TGF-beta1, PDGF, ET-1, bFGF and VEGF from vascular endothelial cells from hypertrophic scar were 60 +/- 8, 30 +/- 4, 0.12 +/- 0.03, 52 +/- 5, 18.1 +/- 1.2 microg/cell, respectively, which were obviously lower than those in normal skin (P0.05).The biological function of vascular endothelial cells was attenuated in the hypertrophic scar, which mightbe the result of the production of large amounts of collagen in the scar tissue, as well as hypoxia.

Dermal defection and the degree of its loss determine the natural process of wound healing, which is the key reason leading to excess scar hyperplasia. The function of tri-dimensional structure in dermis acts as a template to regulate the properties of reparative cells. The template structure induces the reparative cells to grow into the structure which changes the skin mechanic status on wound area. Also, the component of extracellular matrix can affect behaviours of fibroblasts negatively or positively, for the reason that the structure of dermal tissue has a permissive effect on the dermal components in regulating behaviours of reparative cells. Therefore, the behaviors of cells depend on the structure of the template. The suitable tri-dimensional structure of dermis facilitates normal cell cycling. The more the structure of dermis closed to its physiological status, the better the biological behaviors of cells act. Moreover, the integrity as well as the continuity of dermal tissue is the prerequisite for serving as a template. The damage to the integrity and the continuity of dermal tissue may be one of the key reasons to lead abnormal tissue repair and scar formation. Thus, we hypothesize that the loss of dermal template may be one of the mechanism of abnormal scar formation and propose the theory of extracellular matrix framework deficiency or destruction.

To investigate the influence of dermal template on the biomechanical compliance of wound tissue during wound repair.One hundred and forty-four SD rats subjected to full-thickness skin loss on the dorsum were enrolled in the study, and they were randomly divided into A (n = 6, without grafting on wound), B (n = 6, with full thickness skin grafting on wound), C (n = 6, with razor thin skin grafting on wound) and D [n = 6, with acellular dermal matrix (ADM) and razor thin skin grafting on wound] groups. The tissue samples from the wounds were harvested 1, 2, 4, 6, 12 and 20 weeks after the operation. The biomechanical compliance of the wound was assessed by Instron biomechanics tensiometer. The expression of alpha-SMA in the dermal fibroblasts of each group was determined by immunohistochemistry (ABC) method.The biomechanical compliance of the wound in D group was higher than that in A and C groups (P0.05), but lower than that in B group during 4 to 20 weeks after operation (P0.05). The expression of alpha-SMA in D group (7.53 +/- 0.98)% was lower than that in A (26.99 +/- 2.90)% and C (2.18 +/- 2.79)% groups (P0.01), but higher than that in B group at 4 weeks after operation (P0.05).Dermal template might affect the scar formation during wound healing, in improving wound healing quality by enhancing the biomechanical compliance of wound tissue.

To study the proliferation-inhibiting and apoptosis-inducing effects of advanced glycation end products (AGE) modified human serum albumin (AGE-HSA) on human vein endothelial cells.Human umbilical vein endothelial cells ECV304 were cultured in vitro with AGE-HSA of the concentrations of 12.5, 25, 50, 100, and 200 micro g/ml for 6, 12, 24, or 48 hour, then 20 micro l of 5 mg/ml MTT were added and the optical density (OD) at each time point was determined. Another ECV304 cells were cultured with AGE-HAS for 2, 4, or 8 days and then were stained with trypan blue to calculate the number of dead cells so as to calculate the proliferation-inhibiting rate. Another ECV304 cells were cultured with AGE-HAS for 6, 12, 24, or 48 hours and then stained with annexin V Fitc and propidium iodide (PI). Flow cytometry was used to calculate the annexin V Fitc positive cells (early and middle stage apoptotic cells) and Annexin V Fitc/PL positive cells (late apoptotic cells). Inverted microscope, transmission electron microscope, and fluorescence microscope were used to observe the histological changes of apoptotic cells. FCV304 cells incubated with HSA of the above-mentioned and without addition of the other agents concentrations were used as controls.The OD values of ECV304 cells cultured for 48 h with low concentrations (12.5, 25, and 50 micro g/ml) of AGE-HSA were not significantly different from those of the control (1.104 +/- 0.080, 1.098 +/- 0.097 and 1.059 +/- 0.122 VS. 1.159 +/- 0.088, all P0.05). The OD values of ECV304 cells cultured with low concentrations of AGE-HSA for 4 days and 6 days were significantly lower than those in the control group. The OD values of ECV304 cells cultured with high concentrations (100 and 200 micro g/ml) of AGE-HSA for 6 - 48 hours decreased to 0.117 +/- 0.033 and 0.081 +/- 0.020 in comparison with that of the control group (P0.01). Flow cytometry and fluorescence microscopy showed higher proportions of apoptotic cells among the ECV304 cells cultured with high concentrations of AGE-HAS than among the control cells at each time point (P0.01). The numbers of cells in the control group exponentially increased after culture for 2, 4, and 6 days. The number of cells cultured with low concentrations of AGE-HAS for 2 days was not significantly different from that of the control group (P0.05), however, the numbers of cells cultured with low concentrations of AGE-HAS for 4 and 6 days were significantly lower than those of the control group (both P0.01). The numbers of cells cultured with 100 or 200 micro g/ml AGE-HAS for 2 days were significantly lower than those of the control group (both P0.01) with a proliferation-inhibiting rate of 39.56% +/- 2.82% and 60.32% +/- 4.51% respectively. The apoptotic rates in cells cultured with low concentrations of AGE-HAS for 48 hours were not significantly different from those in the control group. The apoptotic rates in cells cultured with 100 or 200 micro g/ml AGE-HAS for 6, 12, 24, or 48 hours were significantly higher than those in the control group (all P0.01). The apoptotic rates in 200 micro g/ml group at different time points were significantly higher than those in the 100 micro g/ml group (P0.05 or 0.01). The apoptotic rate and number of apoptotic cells increased along with the increase of culture time and concentration of AGE-HAS. Microscopy showed morphological changes among the cells cultured with 100 micro g/ml AGE-HAS for 6, 12, 24, and 48 hours and the numbers of apoptotic cells, mainly late apoptotic cells, and dead cells increased remarkably since the cells were cultured for 48 hours.AGE-HSA inhibits the proliferation of vascular endothelial cells and induces apoptosis in dose and time dependent manner. AGE modification-induced pathobiological cascade may be involved in the pathogenesis of impaired wound healing in diabetes by the mechanism of angiogenesis retardation.

It is found that these amorphous alloys have been transformed into crystalline phase with grain size of 20–40 nm after annealing at temperature from 450–550°C for 30 min. Some new phases such as Fe3Si are observed and the lattice constant of α-Fe is shortened. These can not be explained by the previous theory about process of diffusion, nucleation and growth of the crystals.Instead, we explain the experimental results by the model of free volume and shearing deposition. If properly applied, shock wave treatment of amorphous alloys would be a promising method for synthesizing new crystalline phases of multi-component systems.