A new strategy of using low-dose caffeic acid carbon nanodots for high resistance to poorly differentiated human papillary thyroid cancer.

Thyroid cancer is one of the most common endocrine malignancies in clinical practice. Traditional surgery and radioactive iodine ablation have poor treatment results for poorly differentiated thyroid cancer, and there is a risk of metastasis and recurrence. In this study, caffeic acid, a natural herbal extract with certain biological activity, has been as precursor to prepare new caffeic acid carbon nanodots via a one-step hydrothermal method. The caffeic acid carbon nanodots retains part of the structure and biological activity of caffeic acid, and have good biocompatibility, water solubility and stability. The construction of the carbon nanodots could effectively improve their bio-absorption rate and the efficacy. In vitro cell experiments showed that low-dose caffeic acid carbon nanodots had a significant inhibitory effect on poorly differentiated papillary thyroid carcinoma BCPAP cells. At low concentrations of 16 µg/mL, the inhibition rate of human thyroid cancer cells BCPAP was ~ 79%. The anti-tumor mechanism was predicted and verified by transcriptome, real-time quantitative PCR and western blot experiments. The caffeic acid carbon nanodots showed to simultaneously downregulate the expression of KRAS, p-BRAF, p-MEK1 and p-ERK1/2, the four continuous key proteins in a MAPK classical signaling pathway. In vivo experiments further confirmed the caffeic acid carbon nanodots could significantly inhibit the tumorigenicity of xenografts in papillary thyroid carcinoma at quite low doses. This piece of work provides a new nanomedicine and therapeutic strategy for highly resistant poorly differentiated papillary thyroid carcinoma.

Carbon nanodots constructed by ginsenosides and their high inhibitory effect on neuroblastoma.

BACKGROUND: Neuroblastoma is one of the common extracranial tumors in children (infants to 2 years), accounting for 8 ~ 10% of all malignant tumors. Few special drugs have been used for clinical treatment currently. RESULTS: In this work, herbal extract ginsenosides were used to synthesize fluorescent ginsenosides carbon nanodots via a one-step hydrothermal method. At a low cocultured concentration (50 µg·mL- 1) of ginsenosides carbon nanodots, the inhibition rate and apoptosis rate of SH-SY5Y cells reached ~ 45.00% and ~ 59.66%. The in vivo experiments showed tumor volume and weight of mice in ginsenosides carbon nanodots group were ~ 49.81% and ~ 34.14% to mice in model group. Since ginsenosides were used as sole reactant, ginsenosides carbon nanodots showed low toxicity and good animal response. CONCLUSION: Low-cost ginsenosides carbon nanodots as a new type of nanomedicine with good curative effect and little toxicity show application prospects for clinical treatment of neuroblastoma. It is proposed a new design for nanomedicine based on bioactive carbon nanodots, which used natural bioactive molecules as sole source.

CO2-Containing Reservoir Evaluation Based on the Joint Inversion of Nuclear Logs and Resistivity Logs: A Case Study of Ultrahigh-Temperature and High-Pressure Gas Reservoirs in the Yinggehai Basin, China.

Due to the unique characteristics of reservoirs in the Yinggehai Basin in the South China Sea, such as high temperature and high pressure (HPHT), low porosity, low permeability, complex pore structure, and high lime content, the log responses of these reservoirs have very complex characteristics, which makes it difficult to evaluate reservoir parameters accurately. In addition, most reservoirs in Ledong Block of the Yinggehai Basin in the South China Sea contain CO2, posing great difficulties for subsequent exploration and development. Accurate evaluation of CO2 layers is of paramount importance for the development of oil and gas fields. In this study, we used a method for the joint inversion of multiple well logs to evaluate the reservoirs and determine CO2 saturation level and other formation parameters. We optimized the joint inversion model based on the characteristics of the reservoirs in the Yinggehai Basin and adjusted the forward simulation model to consider the effects of high temperature and high pressure on gas density. In view of high lime content in the formations in this area, we adjusted the resistivity forward simulation model to consider the effect of lime content. The inversion results show that the values of porosity, permeability, and water saturation level obtained through inversion are largely consistent with the core data. The CO2 saturation level determined through joint inversion is 22%, which represents a deviation of less than 10% from the drilling system testing (DST) result, indicating that the joint inversion method is accurate. The error in the water saturation level determined through the joint inversion method is smaller than that in the calculated results from conventional multimineral inversion models. We performed forward simulation of the results calculated with the joint inversion method and compared the results of forward simulation with actual log curves. For the sandstone interval, the results of forward simulation are largely consistent with the actual log curves, indicating that the joint inversion method is accurate. In summary, the method presented in this paper can accurately determine reservoir parameters and provide strong support for the exploration and development of oil and gas fields in the Yinggehai Basin in the South China Sea.

Hyperprogressive Disease After Immunotherapy: A Case Report of Pulmonary Enteric Adenocarcinoma.

Primary pulmonary enteric adenocarcinoma (PEAC) is a rare invasive adenocarcinoma clinically similar to metastatic colorectal adenocarcinoma (MCRC). Although many studies have addressed the differential diagnosis of PEAC, few have described the treatment of PEAC, especially using immunotherapy. This report describes a 61-year-old man who presented initially with pain in the ribs. Pathological analysis of biopsy samples shows malignant tumors of the right pleura, and next-generation sequencing of 26 genes showed a KRAS gene mutation. Positron emission tomography-computed tomography (PET-CT) found no evidence of gastrointestinal malignancy. Due to multiple metastases, the patient could not undergo radical surgery. The patient was treated with a combination chemotherapy regimen of paclitaxel plus carboplatin, along with sindilizumab immunotherapy, but, after one cycle of treatment, the tumor showed a hyperprogressive state. The patient is still being monitored regularly. These findings indicate that chemotherapy combined with immunotherapy may be ineffective in the treatment of primary PEAC with positive driver genes.

Optimization of shaped pulses for radio frequency excitation in NMR logging.

The radio frequency (RF) excitation pulse of the nuclear magnetic resonance (NMR) logging tool can realize slice measurement by designing shaped pulses. In the case of a certain main magnetic field, the accuracy of the shaped pulse design has a very important impact on the signal-to-noise ratio (SNR) of the NMR signal and the measurement of the short relaxation signal. Hard pulse excitation will produce an undesirable infinite number of side lobes that may perturb the spins in unwanted regions. Soft pulse can achieve selective excitation and has a better slice profile and shorter energy release time while it is not conducive to the measurement of short relaxation signals. This article focuses on the design of shaped pulses in extreme downhole environments and analyzes the characteristics of the three shaped pulses in the two cases of equivalent bandwidth and equivalent pulse duration. At the same time, a kind of RF-shaped pulse transmitting circuit with phase difference control is realized. According to the pulse type optimization strategy, the appropriate shaped pulse is selected. When echo spacing (TE) >0.6 ms, the SNR can be increased to more than 12%. When TE is small, it will automatically switch to the hard pulse mode, which is good for short relaxation measurement.

Polystyrene@poly(ar-vinylbenzyl)trimethylammonium-co-acrylic acid core/shell pH-responsive nanoparticles for active targeting and imaging of cancer cell based on aggregation induced emission.

Doubly charged pH-responsive core/shell hydrogel nanoparticles with green fluorescence were prepared and were shown to be viable bioprobes for active targeting tumor tissue and imaging of cancer cells. Via emulsionfree copolymerization hydrogel nanoparticles as VANPs were prepared, the core of which was polystyrene (Ps) and the shell was comprised of strongly positive electrolyte (ar-vinylbenzyl)trimethylammonium (VBTAC) with weak negative electrolyte acrylic acid (AA). Through conventional amidation, the shell was conjugated with cell-specific folic acid (FA), denoted as VANPs-FA. Then, negatively charged sulfonated 9,10-distyrylanthracene derivatives (SDSA) based on aggregation induced emission (AIE), was binding tightly to positively charged VBTAC of VANPs-FA shell. The prepared double charged fluorescent core/shell hydrogel nanoparticles abbreviated as VANPs-FS, showed excitation/emission wavelengths at ~420/528 nm. Dynamic light scattering (DLS) measurements were performed to determine the size and surficial zeta potential of VANPs-FS. Under proper ratio of VBTAC to AA, the VANPs-FS was stable (~ 64.63 nm, -20.2 mV) at high pH (> 7), started to aggregate (~ 683.0 nm, -3.2 mV) at pH around 6, and can redispers at low pH (< 5). The MTT analysis proved that VANPs-FS had good biocompatibility and low cytotoxicity. The targeting effectiveness of VANPs-FS was confirmed by confocal laser scanning microscopy (CLSM). Graphical abstract Detailed synthetic route of VANPs-FS (top) and schematic cancer tumor-target aggregation of pH-sensitive VANPs-FS with enhanced retention and rapid cancer cell imaging (bottom).

Blood oxygen level-dependent functional magnetic resonance imaging can evaluate the efficiency of transcatheter arterial chemoembolization in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is among the most common malignant tumors worldwide, and transcatheter arterial chemoembolization (TACE) technology has become the first-line treatment for advanced HCC. Another important, recently developed technique is blood oxygen level-dependent functional magnetic resonance imaging (BOLD-fMRI), which utilizes hemoglobin as an endogenous contrast agent and measures deoxygenated hemoglobin content by sampling the oxygen content of tissues, thus reflecting the hemodynamics and pathophysiologic changes in body organs. Currently this technology is being used in patients with liver tumors; that is, it serves as an important tool in follow-up after TACE. The present paper summarizes these developments.

Ectopic pregnancy in the liver incidentally diagnosed by imaging: A case report.

The present report describes the case of a 31-year-old woman diagnosed with an ectopic pregnancy in the liver. The patient presented with amenorrhea for 40 days and abdominal distention for 27 days. A liver mass had been detected 6 days prior to presentation. Using ultrasound (US), a hyperechoic mass with a fluid sonolucent area was detected in the right hepatic lobe. Examination by computed tomography (CT) revealed the presence of a mass in the right hepatic lobe with a slightly low-density peripheral region and an oval central portion of lower density in the plain scan; the enhanced scan revealed a significantly enhanced peripheral region and a non-enhanced central portion. 18F-fluodeoxyglucose (FDG) positron emission tomography (PET)-CT showed a mass in the right hepatic lobe with an increased intake of FDG in the peripheral region (maximum standard uptake value, 5.7) and a non-increased intake of FDG in the central portion. The patient was then subjected to hysteroscopy and laparoscopy. Histopathologically, the mass was an ectopic pregnancy. The patient recovered following the surgery. In conclusion, a timely diagnosis of ectopic pregnancy was made for a 31-year-old women with an ectopic pregnancy in the liver on the basis of US, CT and PET-CT imaging results, which enabled surgery to be undertaken prior to any serious consequences. These observations may be helpful for the diagnosis of similar cases in the future.

Real-time detection of dielectric anisotropy or isotropy in unconventional oil-gas reservoir rocks supported by the oblique-incidence reflectivity difference technique.

Current geological extraction theory and techniques are very limited to adequately characterize the unconventional oil-gas reservoirs because of the considerable complexity of the geological structures. Optical measurement has the advantages of non-interference with the earth magnetic fields, and is often useful in detecting various physical properties. One key parameter that can be detected using optical methods is the dielectric permittivity, which reflects the mineral and organic properties. Here we reported an oblique-incidence reflectivity difference (OIRD) technique that is sensitive to the dielectric and surface properties and can be applied to characterization of reservoir rocks, such as shale and sandstone core samples extracted from subsurface. The layered distribution of the dielectric properties in shales and the uniform distribution in sandstones are clearly identified using the OIRD signals. In shales, the micro-cracks and particle orientation result in directional changes of the dielectric and surface properties, and thus, the isotropy and anisotropy of the rock can be characterized by OIRD. As the dielectric and surface properties are closely related to the hydrocarbon-bearing features in oil-gas reservoirs, we believe that the precise measurement carried with OIRD can help in improving the recovery efficiency in well-drilling process.

Imaging of Hepatic Ectopic Pregnancy by 18F-FDG PET/CT.

Hepatic ectopic pregnancy is an uncommon form of extrauterine pregnancy. A 31-year-old woman had acute abdominal pain and distention. Laboratory examination showed significantly increased serum ß-human chorionic gonadotropin level. Both ultrasound and MRI identified a lesion located at the right lobe of the liver. FDG PET/CT was performed to determine whether the other causes of elevated ß-human chorionic gonadotropin level, which showed an oval mass with mid peripherally increased FDG activity. After surgery, pathological results confirmed a diagnosis of hepatic ectopic pregnancy.

Molecular dynamics and composition of crude oil by low-field nuclear magnetic resonance.

Nuclear magnetic resonance (NMR) techniques are widely used to identify pure substances and probe protein dynamics. Oil is a complex mixture composed of hydrocarbons, which have a wide range of molecular size distribution. Previous work show that empirical correlations of relaxation times and diffusion coefficients were found for simple alkane mixtures, and also the shape of the relaxation and diffusion distribution functions are related to the composition of the fluids. The 2D NMR is a promising qualitative evaluation method for oil composition. But uncertainty in the interpretation of crude oil indicated further study was required. In this research, the effect of each composition on relaxation distribution functions is analyzed in detail. We also suggest a new method for prediction of the rotational correlation time distribution of crude oil molecules using low field NMR (LF-NMR) relaxation time distributions. A set of down-hole NMR fluid analysis system is independently designed and developed for fluid measurement. We illustrate this with relaxation-relaxation correlation experiments and rotational correlation time distributions on a series of hydrocarbon mixtures that employ our laboratory-designed downhole NMR fluid analyzer. The LF-NMR is a useful tool for detecting oil composition and monitoring oil property changes. Copyright © 2016 John Wiley & Sons, Ltd.

Pattern transitions of oil-water two-phase flow with low water content in rectangular horizontal pipes probed by terahertz spectrum.

The flow-pattern transition has been a challenging problem in two-phase flow system. We propose the terahertz time-domain spectroscopy (THz-TDS) to investigate the behavior underlying oil-water flow in rectangular horizontal pipes. The low water content (0.03-2.3%) in oil-water flow can be measured accurately and reliably from the relationship between THz peak amplitude and water volume fraction. In addition, we obtain the flow pattern transition boundaries in terms of flow rates. The critical flow rate Qc of the flow pattern transitions decreases from 0.32 m3 h to 0.18 m3 h when the corresponding water content increases from 0.03% to 2.3%. These properties render THz-TDS particularly powerful technology for investigating a horizontal oil-water two-phase flow system.

[A case of PET-CT imaging for primary hyperparathyroidism].

OBJECTIVE: To explore the 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (¹8F-FDG) positron emission tomography/computed tomography (PET-CT) manifestations and functions in patients with primary hyperparathyroidism (pHPT). 
 METHOD: The diagnosis of 1 case of double parathyroid adenomas secondary to pPTH was reported and the related literature was reviewed.
 RESULTS: PET-CT showed two nodus shadow with slightly lower density compared with muscle, clear boundary and uniform density. Simultaneously, images also showed multiple enhanced FDG uptake of bone lesions in skeletal system. The maximum standard uptake values for ¹8F-FDG in the destructive bone lesions were more than 10. 
 CONCLUSION: ¹8F-FDG PET-CT is a well-established imaging technique for the diagnosis in pHPT. It not only can clearly visualize systemic lesions and accurately assess the extent of the disease, but also can accurately localize parathyroid adenoma. After resection of parathyroid adenoma, FDG PET-CT imaging can be useful to see the response to treatment and osteoblastic changes in brown tumor.

Lattice Boltzmann simulation of shale gas transport in organic nano-pores.

Permeability is a key parameter for investigating the flow ability of sedimentary rocks. The conventional model for calculating permeability is derived from Darcy's law, which is valid only for continuum flow in porous rocks. We discussed the feasibility of simulating methane transport characteristics in the organic nano-pores of shale through the Lattice Boltzmann method (LBM). As a first attempt, the effects of high Knudsen number and the associated slip flow are considered, whereas the effect of adsorption in the capillary tube is left for future work. Simulation results show that at small Knudsen number, LBM results agree well with Poiseuille's law, and flow rate (flow capacity) is proportional to the square of the pore scale. At higher Knudsen numbers, the relaxation time needs to be corrected. In addition, velocity increases as the slip effect causes non negligible velocities on the pore wall, thereby enhancing the flow rate inside the pore, i.e., the permeability. Therefore, the LBM simulation of gas flow characteristics in organic nano-pores provides an effective way of evaluating the permeability of gas-bearing shale.

[High field magnetic resonance background suppression diffusion imaging in the diagnosis of liver foci of space occupying lesion].

OBJECTIVE: To explore the diagnostic value of the 3.0T magnetic resonance liver diffusion weighted imaging with background suppression (DWIBS) in liver foci of space occupying lesion. METHODS: A total of 43 cases of liver bureau stove perch pathological change were included: 15 were hepatocellular carcinoma (HCC) with 24 lesions; 7 were liver metastatic tumor with 13 lesions; 10 were liver hemangioma with 12 lesions; and 11 liver cyst with 20 lesions. After taking the conventional T1WI and T2WI sequence, the magnetic resonance background suppression diffusion imaging technology (diffusion weighted imaging with background suppression, DWIBS) was applied, following the dynamic enhanced scan. With the MRI to DWIBS workstation for classifying positron emission computed tomography (PET) processing, the T2WI diagram and dynamic enhanced diagram were compared respectively for the 3 sequences of lesion detection rate, T2WI, and DWIBS, to enhance the delay time between the two joint and combined lesion detection rate. With the MRI workstation software scanning image generation ADC diagram, the ADC values were measured for liver cancer, liver metastatic tumor, liver hemangioma and liver cysts. RESULTS: The 3 sequences of detection rates of the T2WI, DWIBS and enhanced delay period T1WI were 91.3%, 94.2%, and 95.6%. The detection rate of DWIBS plus T2WI was 92.7%; that of T2WI plus enhanced delay time was 94.9%, and that of DWIBS plus enhanced delay time was 96.3%, with the rate of DWIBS plus enhanced delay period obviously higher than that of the DWIBS plus T2WI (P<0.05). The ADC value of the benign liver tumor was obviously higher than that of the malignant tumors: hepatic cyst (2.614 ± 0.57)×10⁻³ mm²/s, liver hemangioma (2.055 ± 0.21)×10⁻³ mm²/s, metastatic carcinoma (1.374 ± 0.32)× 10⁻³ mm²/s, and liver cancer (1.287 ± 0.14)×10⁻³ mm²/s. Except for the liver cancer and the liver metastatic tumor, there was significant difference between the other groups (P<0.05). CONCLUSION: Combing the DWIBS technology, the PET-like images and the ADC value acquired, the combined enhanced sequences could further facilitate the demonstration of the liver foci of space occupying lesion, the accuracy of identification and diagnosis of the liver foci of space occupying lesion.

VEGF(165) expressing bone marrow mesenchymal stem cells differentiate into hepatocytes under HGF and EGF induction in vitro.

A short half-life and low levels of growth factors in an injured microenvironment necessitates the sustainable delivery of growth factors and stem cells to augment the regeneration of injured tissues. Our aim was to investigate the ability of VEGF(165) expressing bone marrow mesenchymal stem cells (BMMSCs) to differentiate into hepatocytes when cultured with hepatocyte growth factor (HGF) and epidermal growth factor (EGF) in vitro. We isolated, cultured and identified rabbit BMMSCs, then electroporated the BMMSCs with VEGF(165)-pCMV6-AC-GFP plasmid. G418 was used to select transfected cells and the efficiency was up to 70%. The groups were then divided as follows: Group A was electroporated with pCMV6-AC-GFP plasmid + HGF + EGF and Group B was electroporated with VEGF(165)-pCMV6-AC-GFP plasmid +HGF + EGF. After 14 days, BMMSCs were induced into short spindle and polygonal cells. Alpha-fetoprotein (AFP) was positive and albumin (ALB) was negative in Group A, while both AFP and ALB were positive in group B on day 10. AFP and ALB in both groups were positive on day 20, but the quantity of AFP in group B decreased with prolonged time and was about 43.5% less than group A. The quantity of the ALB gene was increased with prolonged time in both groups. However, there was no significant difference between group A and B on day 10 and 20. Our results demonstrated that VEGF(165)-pCMV6-AC-GFP plasmid modified BMMSCs still had the ability to differentiate into hepatocytes. The VEGF(165) gene promoted BMMSCs to differentiate into hepatocyte-like cells under the induction of HGF and EGF, and reduced the differentiation time. These results have implications for cell therapies.

[Microbial profile and antibiotic susceptibility of chronic rhinosinusitis].

OBJECTIVE: To investigate distribution and drug-susceptibility of bacteria in patients with chronic rhinosinusitis. METHOD: The purulent discharges or mucous membrane lesions were collected from the sinus of 51 patients with chronic rhinosinusitis receiving sinus surgery. The clinical specimens were incubated and the drug susceptibility was analyzed. RESULT: Of 51 specimens, 41 (80.39%) showed positive results in bacteria culture. The antibiotic susceptibility was as follows: vancomycin-100%, moxifloxacin-100%, levofloxacin-92.31%, rifampin-90.91%, ciprofloxacin-81.58%, SMZ-TMP-67.65%, azithromycin-47.62%, clarithromycin-45.00%, ampicillin sodium and sulbactam sodium-35.90%, cefatriaxone-39.39%, cefuroxime sodium-30.43%, penicillin-8.33%. CONCLUSION: There are bacteria infections in most of chronic rhinosinusitis. The fluoroquinolones should be preferred in sinus surgery.