High success rates in clinical trials on keratoconic corneas suggest the possibility of efficient treatment against myopic progression. This study quantitatively investigated the in vitro ultrastructural effects of a photooxidative collagen cross-linking treatment with photosensitizer riboflavin and UVA light in human corneo-scleral collagen fibrils. A total of 30.8 × 2 mm corneo-scleral strips from donor tissue were sagittally dissected using a scalpel. The five analytic parameters namely fibril density, fibril area, corneo-scleral thickness, fibril diameter, and fibril arrangement were investigated before and after riboflavin-UVA-catalyzed collagen cross-linking treatment. Collagen cross-linking effects were measured at the corneo-scleral stroma and were based on clinical corneal cross-linking procedures. The structural response levels were assessed by histology, digital mechanical caliper measurement, scanning electron microscopy, and atomic force microscopy. Riboflavin-UVA-catalyzed collagen cross-linking treatment led to an increase in the area, density, and diameters of both corneal (110, 112, and 103 %) and scleral (133, 133, and 127 %) stromal collagens. It also led to increases in corneal (107 %) and scleral (105 %) thickness. Collagen cross-linking treatment through riboflavin-sensitized photoreaction may cause structural property changes in the collagen fibril network of the cornea and sclera due to stromal edema and interfibrillar spacing narrowing. These changes were particularly prominent in the sclera. This technique can be used to treat progressive keratoconus in the cornea as well as progressive myopia in the sclera. Long-term collagen cross-linking treatment of keratoconic and myopic progression dramatically improves weakened corneo-scleral tissues.

Abstract. This study examined the effect of the cross-linking with riboflavin-ultraviolet A (UVA) irradiation on the chemical bonds and ultrastructural changes of human sclera tissues using Raman spectroscopy and atomic force microscopy (AFM). Raman spectroscopy of the normal and cross-linked human sclera tissue revealed different types of the riboflavin-UVA and collagen interactions, which could be identified from their unique peaks, intensity, and shape. Raman spectroscopy can prove to be a powerful tool for examining the chemical bond of collagenous tissues at the molecular level. After riboflavin-UVA treatment, unlike a regular parallel arrangement of normal collagen fibrils, the AFM image revealed interlocking arrangements of collagen fibrils. The observed changes in the surface topography of the collagen fibrils, as well as in their chemical bonds in the sclera tissue, support the formation of interfibrilar cross-links in sclera tissues. C 2011 Society of Photo-Optical Instrumentation Engineers (SPIE).

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Biochar has attracted considerable attention in numerous industrial and environmental applications because of its advantageous properties. Pyrolysis, a cost-effective and eco-friendly engineering technique for improving biochar’s physicochemical and adsorption properties, is important in a variety of environmental applications. The effect of pyrolysis temperature and ball-milling time on the physicochemical properties of biochar derived from rice bran was investigated in this study, and its effectiveness in the aqueous removal of rhodamine B (RhB) dye was evaluated. The biochar was prepared by pyrolyzing rice bran at various temperatures, i.e., 400, 500, 600, and 700 ℃ (RB 400, RB 500, RB 600, and RB 700, respectively). In addition, in order to investigate the effect of the ball-milling time on the RB 600 biochar, it was milled for 30, 60, 120, 180, and 240 min. The surfaces of the raw material and biochar exhibited honeycomb-like pores and a layered structure. The biochar structure shrank, became fragile, and cracked as the pyrolysis temperature increased. After ball milling, the honeycomb-like pores and layered structure of the pristine biochar were transformed into irregular particles. The particle size decreased as milling time increased. Furthermore, the physicochemical properties of ball-milled biochar were superior to those of pristine biochar. According to the Raman spectral analysis, the ID/IG ratio decreased as the pyrolysis temperature and the milling time increased, indicating a decreased disorder and an increased graphitization in the biochar. The efficiency of RhB removal increased as the pyrolysis temperature and ball-milling time increased, and up to 82% of RhB was removed from 50 mg of biochar milled for 180 min at 600 °C.

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Osteomyelitis is an inflammatory condition of the bone caused by pathogenic bacteria. The causative pathogen is usually oral residing bacteria, but this is a report of patients with osteomyelitis infected with Enterobacteriaceae, which is not common. Enterobacteriaceae has been known to cause in-hospital infections for over last 30 years and is known to have multiple antibiotic resistances. Both cases in this study developed osteomyelitis after removal of the dentigerous cyst. Enterobacter aerogenes was cultured in one patient and Serratia marcescens in the other. After changing antibiotics through antibiotic susceptibility testing, clinical symptoms subsided and radiographic images confirmed that the callus formed and recovered at the same time.

Odontogenic infection in the oral and maxillofacial regions caused by bacteria (mostly of oral origin) is one of the most common diseases encountered by dentists. Localized infection can easily be treated with incision and drainage followed by antibiotics. Emergence of multidrug resistant (MDR) bacteria called "Superbacteria" has become one of the serious problems in modern society, due to its small window of opportunity for treatment and high casualty. The acronym "ESKAPE", encompassing the common and serious MDR pathogens stand for Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp. Literature search was performed in Medline, PubMed and Google Scholar ranging from 2012 to 2020. ESKAPE patient's infection period was longer than that of non-ESKAPE group, and the treatment method due to antibiotic resistance was also complicated. The purpose of this study is to investigate infection caused by ESKAPE pathogens in the oral and maxillofacial regions through literature review and to inform dental surgeons of the danger of ESKAPE pathogens and to suggest viable treatment options. Many studies worldwide reported infections associated with ESKAPE pathogens, but only limited number of studies targeted infection in oral and maxillofacial regions. Further research is required with more data on ESKAPE bacteria and their infection, especially in oral and maxillofacial regions.

Acute osteomyelitis caused by Klebsiella pneumoniae is rare in the oral and maxillofacial region. Klebsiella pneumoniae is a Gram-negative bacillus and the normal flora of the human body, but it can cause pneumonia, urinary tract infection, meningitis, and osteomyelitis in patient with compromised immune systems. These infections are mainly caused by nosocomial infection. Microbacterial osteomyelitis was developed by clinical cause such as tooth extraction, fracture, and surgical history, which requires long-term antibiotic administration and surgical treatment. This report describes that a 56-year-old male patient with acute osteomyelitis caused by Klebsiella pneumoniae infection after implant placement was treated with intravenous administration of ertapenem without open surgery treatment. Through this case, we report that antibiotic susceptibility test is essential for the treatment of acute osteomyelitis caused by a bacterial infection resistant to empirical antibiotics, and early administration of appropriate antibiotics can reduce the possibility of extensive bone destruction or additional open surgery.