Vascularized Combined with Nonvascularized Fibula Flap for Mandibular Reconstruction: Preliminary Results of a Novel Technique.

BACKGROUND: Repair of long-span mandibular defects with vascularized free fibular grafts is now a routine procedure. Vertical discrepancy between a graft segment and the occlusal plane can be resolved through several options, including delayed onlay bone graft, iliac bone reconstruction, fibula distraction, and double-barrel fibula flap grafts. The present study (level of evidence: level IV, case series) introduces a new method for mandibular augmentation, wherein a vascularized fibular segment was used to simulate the superior alveolar ridge of the neomandible, whereas a nonvascularized fibular segment was used to reconstruct the inferior border. METHODS: Patients who underwent mandibular reconstruction with this technique between January 2014 and May 2017 were retrospectively reviewed for complications, vertical height, bone resorption rates, and crown to implant (C/I) ratios. RESULTS: The study included 10 patients. Flap loss occurred in 1 patient. A sufficiently long vascular pedicle could be maintained when the average fibular length was up to 15.3 cm to reconstruct long-span mandibular defects. Mean height of the neomandible at 2 weeks and 1 year after surgery was 34.1 and 29.4 mm, respectively. Mean resorption rates of vascularized and nonvascularized fibulas were 10.3% and 3.4%, respectively, at 1 year after surgery. Dental implants were placed in 4 patients with a mean C/I ratio of 1:1.15. CONCLUSION: The present method to reconstruct the alveolar ridge and basal portion of the mandible with vascularized and nonvascularized fibular flaps was safe and effective. It provided sufficient vertical height for lip support and implantation as well as adequate length for long-span mandibular reconstruction.

Down-regulation of Kelch domain-containing F-box protein in Arabidopsis enhances the production of (poly)phenols and tolerance to ultraviolet radiation.

Phenylpropanoid biosynthesis in plants engenders myriad phenolics with diverse biological functions. Phenylalanine ammonia-lyase (PAL) is the first committed enzyme in the pathway, directing primary metabolic flux into a phenylpropanoid branch. Previously, we demonstrated that the Arabidopsis (Arabidopsis thaliana) Kelch domain-containing F-box proteins, AtKFB01, AtKFB20, and AtKFB50, function as the negative regulators controlling phenylpropanoid biosynthesis via mediating PAL's ubiquitination and subsequent degradation. Here, we reveal that Arabidopsis KFB39, a close homolog of AtKFB50, also interacts physically with PAL isozymes and modulates PAL stability and activity. Disturbing the expression of KFB39 reciprocally affects the accumulation/deposition of a set of phenylpropanoid end products, suggesting that KFB39 is an additional posttranslational regulator responsible for the turnover of PAL and negatively controlling phenylpropanoid biosynthesis. Furthermore, we discover that exposure of Arabidopsis to ultraviolet (UV)-B radiation suppresses the expression of all four KFB genes while inducing the transcription of PAL isogenes; these data suggest that Arabidopsis consolidates both transcriptional and posttranslational regulation mechanisms to maximize its responses to UV light stress. Simultaneous down-regulation of all four identified KFBs significantly enhances the production of (poly)phenols and the plant's tolerance to UV irradiation. This study offers a biotechnological approach for engineering the production of useful phenolic chemicals and for increasing a plant's resistance to environmental stress.

Tailoring lignin biosynthesis for efficient and sustainable biofuel production.

Increased global interest in a bio-based economy has reinvigorated the research on the cell wall structure and composition in plants. In particular, the study of plant lignification has become a central focus, with respect to its intractability and negative impact on the utilization of the cell wall biomass for producing biofuels and bio-based chemicals. Striking progress has been achieved in the last few years both on our fundamental understanding of lignin biosynthesis, deposition and assembly, and on the interplay of lignin synthesis with the plant growth and development. With the knowledge gleaned from basic studies, researchers are now able to invent and develop elegant biotechnological strategies to sophisticatedly manipulate the quantity and structure of lignin and thus to create economically viable bioenergy feedstocks. These concerted efforts open an avenue for the commercial production of cost-competitive biofuel to meet our energy needs.

Comparison of static teeth exposure in different postures and its influencing factors of orthognathic surgery patients.

OBJECTIVES: This study aimed to explore the differences and influencing factors of static teeth exposure in different postures of orthognathic surgery patients. METHODS: A total of 148 patients were collected before or after orthognathic surgery. Photographs were taken in the upright and supine positions, and the static teeth exposure values were measured to compare whether the difference among different positions was statistically significant. The patients were classified in accordance with gender, presence or absence of orthodontic brackets, measurement time (preoperative or postoperative), and maxillary movement direction (forward or backward), and the difference of static teeth exposure was compared. The correlation between the difference of static teeth exposure and age was analyzed. RESULTS: The diffe-rence of static teeth exposure between the two positions was 0.99 mm±0.95 mm, which was statistically significant (P=0.000). A statistical difference in the difference of static exposure was observed between female and male (P<0.05). No statistical difference in the difference of static exposure was observed among orthodontic brackets, preoperative or postoperative time points, and maxillary movement direction. In addition, no significant correlation was found between the difference of static teeth exposure and age (r=-0.087, P=0.291). CONCLUSIONS: Compared with the upright position, the static exposure of teeth increased by approximately 0.99 mm in the supine position. The difference of static exposure under different postures was greater in males than in females. Furthermore, orthodontic bracket, maxillary surgery, maxillary movement direction, and age had no effect on the difference of static teeth exposure in different postures.

Prevalence and implications of microplastic contaminants in general human seminal fluid: A Raman spectroscopic study.

Microplastics are ubiquitous environmental contaminants that have been detected in human semen from polluted areas, yet their prevalence and effects in the general population remain largely unexplored. To examine microplastic presence, abundance, polymer types, and associations with semen quality parameters in individuals without occupational exposures, this study was conducted by collecting semen samples from 40 participants undergoing premarital health assessments in Jinan, China. Raman microspectroscopy was employed to identify, quantify, and categorize microplastic polymers, sperm motility was assessed via computer-assisted analysis, and morphology was evaluated through Diff-Quik staining. Correlations between demographics, semen parameters, and microplastic content were examined by statistical analysis. We found that microplastics were detected in all semen samples, with 2 particles per sample (ranging from 0.72 to 7.02 µm). Eight distinct polymers were identified, with polystyrene (31 %) being most prevalent. Semen exposed to polystyrene demonstrated higher sperm progressive motility as compared to polyvinyl chloride exposure group (43.52 ± 14.21 % vs 19.04 ± 13.46 %). Sperm morphological abnormalities were observed but not significantly associated with specific plastic types. In conclusion, this study reveals microplastic contamination in semen from individuals without occupational exposure, with PS, PE, and PVC being the most prevalent and exhibiting differential correlations with sperm progressive motility, and highlight the need for further research into the potential reproductive impacts of microplastic exposure.

[Observation on therapeutic effect of needle-knife for dry mouth and eyes symptoms of primary Sjögren's syndrome].

OBJECTIVE: To compare the clinical efficacy of needle-knife and hydroxychloroquine sulfate in the treatment of dry mouth and eyes symptoms of primary Sjögren's syndrome. METHODS: A total of 60 patients with primary Sjögren's syndrome were randomly divided into an observation group and a control group, 30 cases in each group. In the observation group, needle-knife was used in the range of 2 cm and 2-3 cm below the occipital protuberance, the left and right lateral bone edges of the C2 spinous process, between and within the range of 1.5-3 cm beside the C3 and C4 spinous processes, points between the left and right mandibular angle and the mastoid, the treatment was given 1 time a week for 8 times. The hydroxychloroquine sulfate was applied 0.2 g each time, 2 times daily, 4 weeks as a course and a total of 2 courses in the control group. The changes of salivary flow rate, tear volume, serum immunoglobulin IgG, IgA, IgM contents and Chinese medicine symptom score were observed before and after treatment in the two groups, and the efficacy was evaluated. RESULTS: The total effective rate in the observation group was 86.7% (26/30), which was better than 70.0% (21/30) in the control group (P<0.05). The salivary flow rates, tear volume, serum IgG contents and Chinese medicine symptom scores in the two groups were significantly improved after treatment (all P<0.05), and the improvement degree in the observation group was better than the control group (all P<0.05). There was no significant difference in IgA and IgM between the two groups and before and after treatment (all P>0.05). CONCLUSION: Needle-knife is superior to hydroxychloroquine sulfate in improving dry mouth and eyes symptoms and reducing serum IgG content in patients with primary Sjögren's syndrome.

Enhancing digestibility and ethanol yield of Populus wood via expression of an engineered monolignol 4-O-methyltransferase.

Producing cellulosic biofuels and bio-based chemicals from woody biomass is impeded by the presence of lignin polymer in the plant cell wall. Manipulating the monolignol biosynthetic pathway offers a promising approach to improved processability, but often impairs plant growth and development. Here, we show that expressing an engineered 4-O-methyltransferase that chemically modifies the phenolic moiety of lignin monomeric precursors, thus preventing their incorporation into the lignin polymer, substantially alters hybrid aspens' lignin content and structure. Woody biomass derived from the transgenic aspens shows a 62% increase in the release of simple sugars and up to a 49% increase in the yield of ethanol when the woody biomass is subjected to enzymatic digestion and yeast-mediated fermentation. Moreover, the cell wall structural changes do not affect growth and biomass production of the trees. Our study provides a useful strategy for tailoring woody biomass for bio-based applications.

Basaloid squamous cell carcinoma of the maxillary gingiva: A case report and review of the literature.

Basaloid squamous cell carcinoma (BSCC) is a rare, but distinct histologic variant of squamous cell carcinoma in the head and neck region. It is considered to have a poor prognosis due to its aggressive behavior and tendency to metastasize. The usual sites of BSCC are the floor of the mouth, hypopharynx and base of the tongue, and according to the English-language literature its presentation in the gingiva is somewhat uncommon. In the current report, the unusual case of a 40-year-old male is presented; the patient exhibited a painless irregular mass in the maxillary gingiva, which infiltrated the maxillary sinus, as observed by computed tomography. Hematoxylin and eosin-stained sections revealed a diagnosis of BSCC with typical central necrosis in the cancer nests, which contained basaloid and squamous cells. Immunohistochemistry revealed that p63 was weakly positive, high molecular weight cytokeratin (CK) was focally positive, and S-100, CK7, CK14 and vimentin were negative. It must be noted that histopathology results may be incorrectly interpreted as adenoid cystic carcinoma, undifferentiated carcinoma and basal cell adenocarcinoma.

[Microsurgical anatomy of epiglottic artery and its clinical implications].

OBJECTIVE: To study the microsurgical anatomy of human epiglottic blood vessel to provide exact and reliable data and morphological properties for further studies of laryngeal transplantation, reconstruction and other epiglottis-related diseases. METHODS: Thirty Chinese adult cadavers (27 males and 3 females) were examined for the present study. The cadavers were dissected under magnification along the anatomic planes from skin down to vertebral column. The anterior neck was exposed by a midline incision and extended laterally along the angle of mandible superiorly, and on clavicle inferiorly. After the visualization of laryngeal prominence of thyroid cartilage, strap muscles were resected and superior laryngeal artery and epiglottic blood vessel were exposed under an operating microscope ( original magnification 7 -30). The epiglottic artery was named for the first time. RESULTS: The diameter of superior laryngeal artery was (1. 06+/-0. 16) mm( male: 1. 09 mm+/-0. 12 mm). The diameter of origin epiglottic artery was (0. 79+/-0. 13) mm (male: 0. 81 mm+/-0. 11 mm). The vertical distance between origin epiglottic artery and superior horn of thyroid cartilage was (27. 16+/-3. 85) mm. Epiglottic artery loop was observed in all the cadavers, which could be M-, N-, omega-, or U-shaped and mixed under the thyrohyoid membrane or in the epiglottic vallecula. CONCLUSIONS: These findings could improve the application of epiglottis in laryngeal functional reconstruction after partial laryngectomy, as well as in the prevention of epiglottic artery loop injuries during the operation.

[HLA-G1 molecule expressed by ECV304 cells inhibit cytotoxic activity of allogeneic NK cells].

AIM: To study the effect of HLA-G1 molecule expressed by an endothelial cell line (ECV304) on the cytotoxic activity of allogeneic NK cells. METHODS: ECV304 cells were transfected with recombinant plasmid pcDNA3-HLA-G1 by the liposome transfection, and the expressed HLA-G1 on the cell surface was detected by indirect immunofluorescent assay and flow cytometry. The cytotoxic activity of allogeneic NK cells against ECV304 cells was analyzed by the MTT method. RESULTS: HLA-G1 was expressed on the surface of the transfected ECV304 cells. The specific lysis of NK cells against plasmid pcDNA3 transfected ECV304 was (50.6+/-18.1)%, while the specific lysis against pcDNA3-HLA-G1 transfected ECV304 was (29.7+/-11.4)%, which was significantly lower than the former (P<0.001). CONCLUSION: HLA-G1 expressed by the ECV304 cells can inhibit cytotoxicity of allogeneic NK cells.