Correlation between the maximum standard uptake value and mean Hounsfield unit on single-photon emission computed tomography-computed tomography to discriminate benign and metastatic lesions among patients with breast cancer.

STUDY DESIGN: Retrospective study. PURPOSE: To compare and correlate technetium-99m methylene diphosphonate uptake between benign and metastatic bone lesions using semiquantitative analysis of maximum standard uptake value (SUVmax) and mean Hounsfield unit (HU) in single-photon emission computed tomography-computed tomography (SPECT-CT). OVERVIEW OF LITERATURE: Qualitative interpretation of metastatic bone lesions in breast cancer on bone scintigraphy is often complicated by coexisting benign lesions. METHODS: In total, 185 lesions were identified on bone and SPECT-CT scans from 32 patients. Lesions were classified as metastatic (109 sclerotic lesions) and benign (76 lesions) morphologically on low-dose CT. Semiquantitative analysis using SUVmax and mean HU was performed on the lesions and compared. To discriminate benign and metastatic lesions, the correlation between SUVmax and mean HU was determined using the intraclass correlation coefficients. RESULTS: The SUVmax was higher in metastatic lesions (20.66±14.36) but lower in benign lesions (10.18±12.79) (p<0.001). The mean HU was lower in metastatic lesions (166.62±202.02) but higher in benign lesions (517.65±192.8) (p<0.001). A weak negative correlation was found between the SUVmax and the mean HU for benign lesions, and a weak positive correlation was noted between the SUVmax and the mean HU on malignant lesions with no statistical significance (p=0.394 and 0.312, respectively). The cutoff values obtained were 10.8 for SUVmax (82.6% sensitivity and 84.2% specificity) and 240.86 for the mean HU (98.7% sensitivity and 88.1% specificity) in differentiating benign from malignant bone lesions. CONCLUSIONS: Semiquantitative assessment using SUVmax and HU can complement qualitative analysis. Metastatic lesions had higher SUVmax but lower mean HU than benign lesions, whereas benign lesions demonstrated higher mean HU but lower SUVmax. A weak correlation was found between the SUVmax and the mean HU on malignant and benign lesions. Cutoff values of 10.8 for the SUVmax and 240.86 for the mean HU may differentiate bone metastases from benign lesions.

Neurological infection and complications of SARS-CoV-2: A review.

The primary target of severe acute respiratory syndrome coronavirus 2 is the respiratory system including the nose and lungs, however, it can also damage the kidneys, cardiovascular system and gastrointestinal system. Many recent reports suggested that severe acute respiratory syndrome coronavirus 2 infections can also affect the central nervous system as well as peripheral nervous system that lead to the several neurological complications. The virus can break the blood brain barrier and enters the brain via haematological route or directly by the angiotensin-converting enzyme 2 receptors present on endothelial cells of many cerebral tissues. The neurological complications are manifested by headache, dizziness, encephalopathy, encephalitis, cerebrovascular disease, anosmia, hypogeusia, muscle damage, etc. This review article described the possible routes and mechanism of nervous system infection and the range of neurological complications of COVID-19 that may help the medical practitioners and researchers to improve the clinical treatment and reduce the mortality rate among patients with viral diseases.

Sono-Chemical Synthesis of Silver Quantum Dots Immobilized on Exfoliated Graphitic Carbon Nitride Nanostructures Using Ginseng Extract for Photocatalytic Hydrogen Evolution, Dye Degradation, and Antimicrobial Studies.

Due to modernization and the scarcity of fossil fuel resources, energy demand is continuously increasing. In this regard, it is essential and necessary to create a renewable energy source that can meet future energy demands. Recently, the production of H2 by water splitting and removing pollutants from the water has been essential for issues of energy and environmental demands. Herein, g-C3N4 and Ag-g-C3N4 composite structures have been successfully fabricated by the ultrasonication method. The physio/photochemical properties of prepared g-C3N4 and Ag-g-C3N4 were examined with different analytical techniques such as FTIR, XRD, UV-DRS, SEM, TEM, PL, and XPS analyses. The silver quantum dots (QDS) anchored to g-C3N4 structures performed the profound photocatalytic activities of H2 production, dye degradation, and antimicrobial activity under visible-light irradiation. The Ag/g-C3N4 composite with an Ag loading of 0.02 mole has an optimum photoactivity at 335.40 µmol g-1 h-1, which is superior to other Ag loading g-C3N4 composites. The synthesized Ag/g-C3N4 nanoparticles showed potential microbial inhibition activity during the preliminary screening, and the inhibition zones were comparable to the commercial antibiotic chloramphenicol. The loading of Ag into g-C3N4 paves the suppression, recombination and transfer of photo-generated electron-hole pairs, leading to the enhancement of hydrogen production, the diminishment of pollutants in water under visible light irradiation, and antimicrobial activity against multidrug-resistant pathogens.

Surface modifications of human tooth using Nd:YAG laser for dental applications.

Ablation using Nd:YAG laser has potential in resulting a rough effect on tooth surfaces. The objective of this study is to perform a comparative evaluation of the roughness structure of enamel using the Cynosure Cynergy Nd:YAG laser and 37% phosphoric acid. The results obtained for laser-etched with a pulse width of 300ms show roughed and porous surface with greater depth. Both show remarkable graininess on the surface and fewer indentations. Comparison of the elemental compositions demonstrated that calcium has higher composition when exposed to laser-etch compared to acid-etch. The atomic percentages of calcium in sample A for acid-etched and laser-etched are 5.08 and 9.61, respectively. While acid-etched and laser-etched for sample B are 3.98 and 12.84, respectively. Other elements are not profoundly affected by the technique used in this study. However, carbon and oxygen show inconsistent results for both of the samples. Thus, Nd:YAG laser provides significant effects on the tooth surface but does not primarily modify the element compositions of the tooth. Therefore, Nd:YAG laser can potentially be implemented for etching procedure as a replacement of acid etching technique.