OBJECTIVE: Current mainstream PET scattering correction methods are introduced and evaluated horizontally, and finally, the existing problems and development direction of scattering correction are discussed. METHODS: Based on NeuWise Pro PET/CT products of Neusoft Medical System Co. Ltd. , the simulation experiment is carried out to evaluate the influence of radionuclide distribution out of FOV (field of view) on the scattering estimation accuracy of each method. RESULTS: The scattering events produced by radionuclide out of FOV have an obvious impact on the spatial distribution of scattering, which should be considered in the model. The scattering estimation accuracy of Monte Carlo method is higher than single scatter simulation (SSS). CONCLUSIONS Clinically, if the activity of the adjacent parts out of the FOV is high, such as brain, liver, kidney and bladder, it is likely to lead to the deviation of scattering estimation. Considering the Monte Carlo scattering estimation of the distribution of radionuclide out of FOV, it's helpful to improve the accuracy of scattering distribution estimation.
Positron Emission Tomography Computed Tomography ; Scattering, Radiation ; Computer Simulation ; Brain ; Monte Carlo Method ; Phantoms, Imaging ; Image Processing, Computer-Assisted

The present study explored the effect of co-amorphous technology in improving the dissolution rate and stability of silybin based on the puerarin-silybin co-amorphous system prepared by the spray-drying method. Solid-state characterization was carried out by powder X-ray diffraction(PXRD), polarizing microscopy(PLM), Fourier transform infrared spectroscopy(FT-IR), differential scanning calorimetry(DSC), etc. Saturated powder dissolution, intrinsic dissolution rate, moisture absorption, and stability were further investigated. The results showed that puerarin and silybin formed a co-amorphous system at a single glass transition temperature which was higher than that of any crude drug. The intrinsic dissolution rate and supersaturated powder dissolution of silybin in the co-amorphous system were higher than those of the crude drug and amorphous system. The co-amorphous system kept stable for as long as three months under the condition of 40 ℃, 75% relative humidity, which was longer than that of the single amorphous silybin. Therefore, the co-amorphous technology could significantly improve the dissolution and stability of silybin.
Calorimetry, Differential Scanning ; Desiccation ; Drug Compounding/methods* ; Drug Stability ; Silybin ; Solubility ; Spectroscopy, Fourier Transform Infrared ; Technology ; X-Ray Diffraction

Urinary system tumors affect a huge number of individuals, and are frequently recurrent and progressing following surgery, necessitating lifelong surveillance. As a result, early and precise diagnosis of urinary system cancers is important for prevention and therapy. Histopathology is now the golden stan-dard for the diagnosis, but it is invasive, time-consuming, and inconvenient for initial diagnosis and re-gular follow-up assessment. Endoscopy can directly witness the tumor's structure, but intrusive detection is likely to cause harm to the patient's organs, and it is apt to create other hazards in frequently examined patients. Imaging is a valuable non-invasive and quick assessment tool; however, it can be difficult to define the type of lesions and has limited sensitivity for early tumor detection. The conventional approaches for detecting tumors have their own set of limitations. Thus, detection methods that combine non-invasive detection, label-free detection, high sensitivity and high specificity are urgently needed to aid clinical diagnosis. Optical diagnostics and imaging are increasingly being employed in healthcare settings in a variety of sectors. Raman scattering can assess changes in molecular signatures in cancer cells or tissues based on the interaction with vibrational modes of common molecular bonds. Due to the advantages of label-free, strong chemical selectivity, and high sensitivity, Raman scattering, especially coherent Raman scattering microscopy imaging with high spatial resolution, has been widely used in biomedical research. And quantity studies have shown that it has a good application in the detection and diagnosis of bladder can-cer, renal clear cell carcinoma, prostate cancer, and other cancers. In this paper, several nonlinear imaging techniques based on Raman scattering technology are briefly described, including Raman spectroscopy, coherent anti-Stokes Raman scattering, stimulated Raman scattering, and surface-enhanced Raman spectroscopy. And we will discuss the application of these techniques for detecting urologic malignancy. Future research directions are predicted using the advantages and limitations of the aforesaid methodologies in the research. For clinical practice, Raman scattering technology is intended to enable more accurate, rapid, and non-invasive in early diagnosis, intraoperative margins, and pathological grading basis for clinical practice.
Humans ; Male ; Microscopy/methods* ; Radiopharmaceuticals ; Spectrum Analysis, Raman/methods* ; Technology ; Urologic Neoplasms/diagnosis*

Chinese medicinal material is the foundation of traditional Chinese medicine(TCM) industry. Its quality is not only closely related to the health of residents but also the key to the development of the TCM industry. Pesticide residues, heavy metals and mycotoxins are the major pollutants of Chinese medicinal materials. In recent years, quite a number of rapid detection methods for pollutants have been constructed. Among them, surface-enhanced Raman scattering(SERS), which has been widely used in food chemistry, environmental analysis, and other fields because of its speediness and non-destructiveness, shows its great potential in the pollutant detection in Chinese medicinal material. This paper firstly reviews the application of SERS for the detection of common pollutants in Chinese medicinal material. We then discussed the characteristics and advantages of SERS technique for pesticide detection, including the principle, SERS substrate design, specific recognition, etc. Finally, simultaneous detection of multiple pesticide residues in Chinese medicinal material was explored.
China ; Environmental Pollutants ; Medicine, Chinese Traditional ; Pesticide Residues/analysis* ; Spectrum Analysis, Raman

PURPOSE: The aim of this study was to investigate the effect of different numbers of heat treatments applied to superstructure porcelain on optical, thermal, and phase formation properties of zirconia.MATERIALS AND METHODS: Forty zirconia specimens were prepared in the form of rectangular prism. Specimens were divided into four groups (n = 10) according to the number of firing at heating values of porcelain. Color differences and translucency parameter were measured, and X-ray diffraction (XRD) analysis and differential scanning calorimetry (DSC) were performed. Data were analyzed with analysis of variance (ANOVA).RESULTS: There were no statistically significant differences in ΔE, TP, L, a, and b value changes of the zirconia specimens as a result of repetitive firing processes (P>.05).CONCLUSION: Although additional firing processes up to 4 increase peak density in thermal analysis, additional firing processes up to 4 times can be applied safely as they do not result in a change in color and phase character of zircon frameworks.
Calorimetry, Differential Scanning ; Dental Porcelain ; Fires ; Heating ; Hot Temperature ; X-Ray Diffraction

Oral cancer is a common and deadly malignancy.While multidisciplinary treatment(mainly surgery)has been applied in the treatment of cancer treatment,early diagnosis and complete removal of the primary lesion are essential for a better prognosis.Raman spectroscopy is an optical technique that detects inelastic scattered light generated by the interaction of light and matter.It can detect the vibrational spectra of biochemical and biomolecular structures and tissue conformations,and can provide the "molecular fingerprint" for cells,tissues,and biological fluids.With the development of related technologies and optical instruments,Raman spectroscopy has been widely applied in medical fields.This article reviews the research advances and application of Raman spectroscopy in the diagnosis of oral cancer.
Humans ; Mouth Neoplasms ; Spectrum Analysis, Raman

OBJECTIVE: To develop a fast, sensitive and cost-effective method based on resonance light scattering (RLS) for characterization of protein solubility to facilitate detection of changes in solubility of mutant proteins. METHODS: We examined the response curve of RLS intensities to the protein concentrations in synchronous scanning mode. The curve intersection points were searched to predict the maximal concentrations of the protein in dispersion state, which defined the solubility of the protein in this given state. Bovine serum albumin (BSA, 0-50 g/L) was used as the model to investigate the influences of pH values (6.5, 7.0, and 7.4) and salt concentrations (0.05, 0.10, 0.15, and 0.20 mol/L) on the determined solubility. The solubility of glutathione S-transferase isoenzymes alpha (GSTA, 0-27.0 g/L) and Mμ (GSTM, 0-20.0 g/L) were estimated for comparison. The RLS-based method was used to determine the solubility of uricase (MGU, 0-0.4 g/L) to provide assistance in improving the solubility of its mutants. RESULTS: We identified two intersection points in the RLS response curves of the tested proteins, among which the lower one represented an approximation of the maximal concentration (or the solubility of the protein) in single molecular dispersion, and the higher one the saturated concentration of the protein in multiple molecular aggregation. In HEPES buffer, the two intersection points of BSA (isoelectric point 4.6) both increased with the increase of pH (6.5-7.4), and their values were ~1.2 g/L and ~33 g/L at pH 7.4, respectively; the latter concentration approached the solubility of commercial BSA in the same buffer at the same pH. The addition of NaCl reduced the values of the two intersection points, and increasing salt ion concentration decreased the values of the lower intersection points. Further characterizations of GSTA and GSTM showed that the low concentration intersection points of the two proteins were ~0.7 g/L and ~0.8 g/L, and their high concentration intersection points were ~10 g/L and ~11 g/L, respectively, both lower than those of BSA, indicating the feasibility of the direct characterization of protein solubility by RLS. The two concentration intersection points of MGU were 0.24 g/L and 0.30 g/L, respectively, and the low concentration intersection point of its selected mutant was increased by 2 times. CONCLUSIONS RLS allows direct characterization of the solubility of macromolecular proteins. This method, which is simple and sensitive and needs only a small amount of proteins, has a unique advantage for rapid comparison of solubility of low-abundance protein mutants.
Hydrogen-Ion Concentration ; Light ; Scattering, Radiation ; Solubility ; Spectrum Analysis

Evaporative light scattering detector(ELSD) and charged aerosol detector(CAD) methods were established in this study for the content determination of four kinds of sugars in Zhusheyong Yiqi Fumai(YQFM), and the factors affecting the accuracy of CAD methods were discussed. HPLC-ELSD chromatographic separation was performed on a Shodex Asahipak NH2 P-50 column with acetonitrile-water(75∶25)as the mobile phase, with a flow rate of 0.8 mL·min~(-1), drift tube temperature of 80 ℃. The analysis by HPLC-CAD was performed on the same column with acetonitrile-water as mobile phase for gradient elution, with a flow rate of 0.8 mL·min~(-1), a neb temperature of 45 ℃, and power function(PF) of 1.3. The samples of YQFM were detected by ELSD and CAD respectively. It was found that YQFM was composed of fructose, glucose, sucrose and maltose. The linear relationship of the two methods was good, and the recoveries, reproducibility and stability of these four kinds of sugars measured by the two methods satisfied the requirements of methodology. Both CAD and ELSD detectors were accurate and reliable in detecting saccharides components in YQFM. In addition, it was revealed in this study for the first time that the PF parameter of CAD had an important influence on the accuracy of sugar determination and acted as the key parameter of CAD method. It was also found that for CAD, a non-linear detector, there was no significant difference between the results of linear regression and logarithmic regression.
Aerosols ; Carbohydrates ; Chromatography, High Pressure Liquid ; Light ; Reproducibility of Results ; Scattering, Radiation ; Sugars

The powder X-ray diffraction(PXRD) technique was used to investigate fourteen kinds of Ranunculaceae herbal decoction pieces(RHDP) recorded in Chinese Pharmacopoeia and to explore a novel PXRD quality control method for RHDP. The results indicated that only three RHDP-Paeoniae Radix Alba, Paeoniae Radix Rubra, and Moutan Cortex, contained calcium oxalate monodydrate(COM), whereas no COM existed in other eleven kinds of RHDP. The difference in PXRD for Paeoniae Radix Alba and Paeoniae Radix Rubra from different growing areas were investigated. The quantitative analysis method for COM was discussed by considering the water-boiling manufacturing process of herbal decoction pieces. The water-boiling experiments revealed that the PXRD peaks from COM crystals in RHDP were enhanced significantly after boiling. Paeoniae Radix Alba, Paeoniae Radix Rubra, Moutan Cortex, Aconiti Lateralis Radix Praeparata, Aconiti Radix, Aconiti Kusnezoffii Radix, and Anemone Raddeanae Rhizoma exhibited a similar series of broader peaks in the 2θ region of 15° to 35°, whose origins were discussed on the basis of chemical constituents RHDP reported by other researchers. These diffraction broader peaks most likely originated from periodic orientation of benzene ring in organic molecular crystals of aconitine-and paeonolum-based alkaloids and glycosides chemical constituents, subsequently, possibly from some other organic constituents. The PXRD technique can be used to rapidly identify Cimicifuga heracleifolia with an amorphous dispersion peak and C. dahurica with a sharp-peak feature. Climatidis Radix et Rhizoma exhibited a series of sharp PXRD peaks. The PXRD method can provide a valuable quality control method for RHDP.
Aconitum ; chemistry ; Drugs, Chinese Herbal ; chemistry ; Paeonia ; chemistry ; Phytochemicals ; analysis ; Ranunculaceae ; chemistry ; Rhizome ; chemistry ; X-Ray Diffraction

The single-factor test was used to optimize the high-pressure homogenization method to prepare the phenolic extract nanosuspensions(DBNs). The physicochemical properties of the obtained nanosuspensions were characterized and the cumulative release in vitro was evaluated. The results showed that the drug concentration was 0.5 g·L~(-1), the mass concentrations of PVPK30 and SDS were 0.5 and 0.25 g·L~(-1), respectively, the probe ultrasonic time was 5 min, the homogenization pressure was 900 bar, and the number of homogenization was 2 times. The prepared DBNs had an average particle size of(168.80±0.36) nm, polydispersity index(PDI) of 0.09±0.04, stability index(SI) of 0.85, and DBNs were stable for storage within 30 days. Scanning electron microscopy showed that the particle size of the dragon's blood extract was reduced and the uniformity was improved in the obtained nanosuspensions. X-ray diffraction pattern and differential scanning calorimetry showed that the phenolic extract of dragon's blood was still in an amorphous state after being prepared into nanosuspensions. The results of saturated solubility measurement showed that the solubility of DBNs lyophilized powder reached 6.25 g·L~(-1), while the solubility of DB raw powder was only 28.67 mg·L~(-1). The in vitro dissolution experiments showed that DBNs lyophilized powder accumulated in gastrointestinal fluid for 8 h. The release amount was 90%,the cumulative release of the raw powder in the gastrointestinal fluid for 24 h was less than 1%, and the solubility and dissolution rate of the DBNs lyophilized powder were significantly higher than the DB raw powder. The method is simple in process and convenient in operation, and can successfully prepare uniform and stable nanosuspensions to improve its solubility, and provides a research basis for solving the application limitation of dragon's blood extract.
Calorimetry, Differential Scanning ; Nanoparticles ; Particle Size ; Plant Extracts ; chemistry ; Solubility ; Suspensions ; X-Ray Diffraction