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[en] A sensitive non-enzymatic fluorescent glucose sensor, consisting of vertically aligned ZnO nanotubes (NTs) grown on low-cost printed circuit board substrates, is described. The ZnO NTs were synthesized by a one-step hydrothermal method without using a seed layer. The sensor function is based on the photoluminescence (PL) quenching of ZnO NTs treated with different concentrations of glucose. The UV emission (emission maximum at 384 nm under 325 nm excitation) decreases linearly with increasing glucose concentration. The sensor exhibits a sensitivity of 3.5%·mM−1 (defined as percentage change of the PL peak intensity per mM) and a lower limit of detection (LOD) of 70 μM. This is better than previously reported work based on the use of ZnO nanostructures. The detection range is 0.1–15 mM which makes the sensor suitable for practical uses in glucose sensing. The sensor was successfully applied to the analysis of human blood serum samples. It is not interfered by common concentrations of ascorbic acid, uric acid, bovine serum albumin, maltose, fructose, and sucrose. .
[en] The authors are presenting a novel strategy for global phosphoproteome recognition in practical samples. It integrates metal oxide affinity chromatography (MOAC) and immobilization metal ion affinity chromatography (IMAC). This resulted in a kind of titanium dioxide/ion-based multifunctional probe (dubbed T2M). The T2M combines the features of MOAC and IMAC including their recognition preferences towards mono- and multi-phosphorylated peptides. Hence, they exhibit an outstanding recognition capability towards global phosphoproteome, high sensitivity (the limit of detection of which is merely 10 fmol) and excellent specificity in MALDI-TOF MS detection. Their performance is further demonstrated by the identification of the phosphoproteome in non-fat milk and human saliva. By combining T2M with nano LC-MS/MS, remarkable results are obtained in the tryptic digestion of healthy eye lens and cataract lens phosphoproteomes. A total of 658 and 162 phosphopeptides, respectively, were identified. This indicates that phosphorylation and the appearance of cataract can be related to each other. .
[en] A fluorometric aptamer-based method is described for the determination of aflatoxin B1 (AFB1). The fluorescent dye thioflavin T (ThT) forms a complex with the aptamer against AFB1 (aptamer/ThT), and the fluorescence of the complex is strongly enhanced. On addition of AFB1, it will bind to the aptamer and release ThT. The fluorescence of free ThT is much weaker. The fluorescence of the system, best measured at excitation/emission wavelengths of 440/487 nm, drops gradually in the AFB1 concentration range from 0.2 to 200 ng·mL−1, exhibiting good linearity. The detection limits are 0.2 ng·mL−1 in buffer solution, and 1 ng·mL−1 when applied to plant-derived food. The recovery of AFB1 from spiked foodstuff ranges from 74.7% to 121%. The assay can be performed within 20 min. .
[en] A case of disseminated oral melanoma in a two year old female dog with unilateral protuberance of the eye bulb and progressive seizure is described. Imaging exams revealed increase of the submandibular, maxillary and cerebral regions, nodular pattern in lungs and increased ovarian dimensions. The cytology of the submandibular mass indicated a malignant epithelial proliferation, whereas the excisional biopsy indicated an amelanotic melanoma. At necropsy, a locally infiltrating gingival mass and white nodules in the lymph nodes, kidneys, lung, brain and ovaries were observed, indicative of metastases. Histopathological diagnosis consisted of an undifferentiated malignant metastatic neoplasm. Nucleus with coarse chromatin, prominent nucleoli, bizarre mitotic figures and multinucleated cells were the major malignant features. There was a poor melanocytic pigment differentiation in the peritrabecular space of facial bones, confirmed by Fontana-Masson and Giemsa histochemical techniques. Only a few cells were immunohistochemically positive for PNL-2 and Melan-A and the diagnosis of a disseminated amelanotic melanoma was performed. The diagnostic challenge was based on marked neoplastic undifferentiation, with multisystemic metastasis and mutual involvement of uncommon anatomic sites, associated with a large variability of cellular patterns, highlighting the decisive role of immunohistochemistry for diagnostic confirmation. Therefore, the clinical importance of this study is to warn the clinical and scientific community about the diagnostic challenge, considering the amelanotic melanoma as a differential even in cases of poorly apparent and/or nonpigmented oral lesions. (author)
[en] Unilateral dentigerous cyst is a common entity in the oral cavity. Conversely, bilateral dentigerous cysts are rare, especially in non-syndromic patients. The purpose of the present article was to report a case of a bilateral dentigerous cyst in a non-syndromic patient and discuss about the treatment strategy. A literature review was performed and only eleven articles was report describing this condition. The orthopantomograph showed impacted wisdom teeth and a bilateral well-defined radiolucent unilocular image around the crown of the lower third molars. The diagnostic hypothesis was bilateral dentigerous cyst. The extraction of the impacted teeth was performed followed by excisional biopsy, which confirmed the diagnosis of dentigerous cyst. It might be concluded that radiographic examination is the first resource to intercept initial changes in the dental follicle through observation of the radiolucent halo. The histopathological examination of the surgical specimen becomes essential to reach a final diagnosis of the lesion. (author)
[en] errors in technique, processing and storage, to produce an interpretation. Aim the quality of periapical radiographs was observed during the endodontic treatment stages identifying the most frequent errors. Methodology: The medical records of patients undergoing endodontic treatment were selected. Each chart contained 05 radiographs related to the five stages of endodontic treatment, totaling a sample of 250 radiographs. As radiographs were analyzed by three examiners calibrated. Results In the collected data we analyzed the most frequent radiographic radiographic was the stretching of the radiographic image with 38.86%. In the radiographic processing phase was the mark of digital radio with 33.14%, already analyzing the radio through radio frequency with 83.77% of frequency, according to the analysis of the three times. The endocrine treatment phase in which the results identified the errors was performed during 263, continuation of the initial radiograph with 262 and odontometric with 243 cases found, all found during a radiographic processing phase. The Kappa index was applied and was partially corrected with 0.623, the agreement index between budgets. Conclusion: However, the identification of radiographic errors and a step in qualification is important for new senseless conducts of minimal repetition, failures and errors that interfere with the diagnosis and quality of endodontic treatmen. (author)
[en] Removal of lower third molar corresponds to one of the most common procedures in oral surgery. The extraction can result in several intraoperative or postoperative complications, especially when fully impacted molars are involved.This case report describes a mandibular angle fracture following removal of a fully impacted lower third molar of a 41 years old male patient. The fracture occurred 3 days after the attempt to extract the tooth 38 by a dentist surgeon. Several factors influencing the possibility of fracture including gender, age, dental position, and angulation were reviewed and associated with the injury. A fracture line in the angular region of the jaw was observed in radiological and tomographic analysis, both essential to perform the diagnosis. Open reduction internal fixation treatment approach was realized to ensure the best patient's recovery. We conclude that the difficult to maintain a soft diet and the complete dentition factor could have been determinant to cause the fracture. (author)
[en] Oroantral communication is the unnatural communication of the oral cavity with the maxillary sinus and is often related to the extraction of the upper posterior teeth. The literature presents several treatment options for these cases, including closure with the pedicled flap with the buccal fat pad. The aim of this paper was to report a case of an oroantral fistula in a diabetic patient, discussing surgical alternatives correlated with the patient's systemic disease and local characteristics of the defect. A 55-year-old male patient has a history of the 27 tooth extraction 10 days ago. He has complaining of air passing through the surgical site to the oral cavity. Based on the exams, the definitive diagnosis was oroantral communication and surgical treatment was stipulated to close the communication through two layers with the buccal fat pad followed by the buccal flap. At 8 and half months of follow-up the patient has no complaints and the complete closure of the oroantral communication can be observed. The pediculated buccal fat pad flap followed by the buccal flap proved to be effective in the treatment of oroantral fistula in a controlled diabetic patient. (author)
[en] Introduction: The odontogenic keratocyst comprises a benign cystic lesion originating from the remains of the dental lamina or adjacent epithelial cells, with high recurrence rates, rapid anteroposterior growth within the medullary bone tissue. Objective: This paper aims to describe a case report of an atypical keratocyst. Case Report: A 17-year-old leukoderma patient referred to the Buccomaxillofacial Surgery and Traumatology department due to a complaint of swelling, pain, lower lip numbness, tooth mobility. Imaging exam was requested, a face tomography, which showed a hypodense, osteolytic image, involving the mandibular region. The patient was diagnosed with odontogenic keratocyst and underwent conservative treatment of the lesion. Conclusion: The chosen treatment was individualized and chosen according to the theoretical basis found, considering all complications. The proposed treatment has been effective to date, and the patient remains under clinical and radiographic follow-up, however does not indicate cure of the disease. (author)
[en] Introduction: Anomalies of shape, size, shape, number, structure, and tooth eruption are commonly seen within dentistry. These include hyperdontics or supernumerary teeth. The etiology of this pathology has not really been clarified, but these abnormalities are managed by a complex system of genetic and environmental interaction. Objective: To report to the scientific community a case diagnosed as cleidocranial dysplasia, where 34 supernumerary teeth were removed from a patient. Case report: Female patient,12 years old, diagnosed with cleidocranine dysplasia. A total of 04 procedures were performed for teeth removal and traction of the impacted permanents. All procedures were performed under local anesthesia. Conclusion: The main factor to consider in order to be successful in treating these patients is early diagnosis. Thus, we can seek in a multidisciplinary way an appropriate treatment plan, avoiding future complications for patients with the syndrome. (author)