Dose-Painting Proton Radiotherapy Guided by Functional MRI in Non-enhancing High-Grade Gliomas

AIMS

This study aimed to demonstrate the feasibility and evaluate the dosimetric effect and clinical impact of dose-painting proton radiotherapy (PRT) guided by functional MRI in non-enhancing high-grade gliomas (NE-HGGs).

MATERIALS AND METHODS

The 3D-ASL and T2 FLAIR MR images of ten patients with NE-HGGs before radiotherapy were studied retrospectively. The hyperintensity on T2 FLAIR was used to generate the planning target volume (PTV), and the high-perfusion volume on 3D-ASL (PTV-ASL) was used to generate the simultaneous integrated boost (SIB) volume. Each patient received pencil beam scanning PRT and photon intensity-modulated radiotherapy (IMRT). There were five plans in each modality: (1) Uniform plans (IMRT60 vs. PRT60): 60Gy in 30 fractions to the PTV. (2)-(5) SIB plans (IMRT72, 84, 96, 108 vs. PRT72, 84, 96, 108): Uniform plan plus additional dose boost to PTV-ASL in 30 fractions to 72, 84, 96, 108 Gy. The dosimetric differences between various plans were compared. The clinical effects of target volume and organs at risk (OARs) were assessed using biological models for both tumor control probability (TCP) and normal tissue complication probability (NTCP).

RESULTS

Compared with the IMRT plan, the D2 and D50 of the PRT plans with the same prescription dose increased by 1.27-4.12% and 0.64-2.01%, respectively; the R30 decreased by > 32%; the dose of brainstem and chiasma decreased by > 27% and >32%; and the dose of normal brain tissue (Br-PTV), optic nerves, eyeballs, lens, cochlea, spinal cord, and hippocampus decreased by > 50% (P < 0.05). The maximum necessary dose was 96GyE to achieve >98% TCP for PRT, and it was 84Gy to achieve >91% TCP for IMRT. The average NTCP of Br-PTV was 1.30% and 1.90% for PRT and IMRT at the maximum dose escalation, respectively. The NTCP values of the remaining OARs approached zero in all PRT plans.

CONCLUSION

The functional MRI-guided dose escalation using PRT is feasible while sparing the OARs constraints and demonstrates a potential clinical benefit by improving TCP with no or minimal increase in NCTP for tissues outside the PTV. This retrospective study suggested that the use of PRT-based SIB guided by functional MRI may represent a strategy to provide benefits for patients with NE-HGGs.

Rho kinase inhibitors ameliorate cognitive impairment in a male mouse model of methamphetamine-induced schizophrenia

Schizophrenia (SCZ) is a severe psychiatric disorder characterized by positive symptoms, negative symptoms, and cognitive deficits. Current antipsychotic treatment in SCZ improves positive symptoms but has major side effects and little impact on negative symptoms and cognitive impairment. The pathoetiology of SCZ remains unclear, but is known to involve small GTPase signaling. Rho kinase, an effector of small GTPase Rho, is highly expressed in the brain and plays a major role in neurite elongation and neuronal architecture. This study used a touchscreen-based visual discrimination (VD) task to investigate the effects of Rho kinase inhibitors on cognitive impairment in a methamphetamine (METH)-treated male mouse model of SCZ. Systemic injection of the Rho kinase inhibitor fasudil dose-dependently ameliorated METH-induced VD impairment. Fasudil also significantly suppressed the increase in the number of c-Fos-positive cells in the infralimbic medial prefrontal cortex (infralimbic mPFC) and dorsomedial striatum (DMS) following METH treatment. Bilateral microinjections of Y-27632, another Rho kinase inhibitor, into the infralimbic mPFC or DMS significantly ameliorated METH-induced VD impairment. Two proteins downstream of Rho kinase, myosin phosphatase-targeting subunit 1 (MYPT1; Thr696) and myosin light chain kinase 2 (MLC2; Thr18/Ser19), exhibited increased phosphorylation in the infralimbic mPFC and DMS, respectively, after METH treatment, and fasudil inhibited these increases. Oral administration of haloperidol and fasudil ameliorated METH-induced VD impairment, while clozapine had little effect. Oral administration of haloperidol and clozapine suppressed METH-induced hyperactivity, but fasudil had no effect. These results suggest that METH activates Rho kinase in the infralimbic mPFC and DMS, which leads to cognitive impairment in male mice. Rho kinase inhibitors ameliorate METH-induced cognitive impairment, perhaps via the cortico-striatal circuit.

[Clinical value of ultrasound-guided radiofrequency ablation in the treatment of retroperitoneal tumors]

Objective: To explore the clinical value of ultrasound-guided radiofrequency ablation in the treatment of retroperitoneal tumors. Methods: The clinical data of 13 patients with retroperitoneal tumors treated with ultrasound-guided radiofrequency ablation in the First Affiliated Hospital of Zhengzhou University from January 2018 to January 2020 were analyzed retrospectively. The ablation effect was evaluated and the postoperative complications were observed. The changes of tumor volume before and after radiofrequency ablation were compared. Results: The symptoms of pain and dyspepsia were significantly improved after radiofrequency ablation, and the hospital stay was (9.2±2.9) days. The tumor was ablated completely in 10 cases, tumor residual in 1 case and tumor metastasis in 2 cases. One patient had postoperative duodenal perforation complicated with intra-abdominal infection, and no serious complications occurred in other patients. There were 20 lesions in 13 patients. The maximum diameter of 20 lesions before operation and 1, 3, 6 months after operation were (39.5±15.9) mm, (30.6±4.9)mm, (15.6±7.7) mm and (9.9±3.1) mm, respectively, the maximum diameters of 1, 3 and 6 months after operation were smaller than that before operation (P<0.05). Conclusion: Ultrasound-guided radiofrequency ablation is a real-time, accurate, safe and effective minimally invasive treatment with few complications, and has a high clinical value for retroperitoneal tumors.

Mice with exonic RELN deletion identified from a patient with schizophrenia have impaired visual discrimination learning and reversal learning in touchscreen operant tasks

The Reelin gene (RELN) encodes a large extracellular protein, which has multiple roles in brain development and adult brain function. It activates a series of neuronal signal transduction pathways in the adult brain that function in synaptic plasticity, dendritic morphology, and cognitive function. To further investigate the roles of Reln in brain function, we generated a mouse line using the C57BL/6 J strain with the specific Reln deletion identified from a Japanese patient with schizophrenia (Reln-del mice). These mice exhibited abnormal sociality, but the pathophysiological significance of the Reln deletion for higher brain functions, such as learning and behavioral flexibility remains unclear. In this study, cognitive function in Reln-del mice was assessed using touchscreen-based visual discrimination (VD) and reversal learning (RL) tasks. Reln-del mice showed normal learning in the simple VD task, but the learning was delayed in the complex VD task as compared to their wild-type (WT) littermates. In the RL task, sessions were divided into early perseverative phase (sessions with <50% correct) and later learning phase (sessions with ≥50% correct). Reln-del mice showed normal perseveration but impaired relearning ability in both simple RL and complex RL task as compared to WT mice. These results suggest that Reln-del mice have impaired learning ability, but the behavioral flexibility is unaffected. Overall, the observed behavioral abnormalities in Reln-del mice suggest that this mouse model is a useful preclinical tool for investigating the neurobiological mechanism underlying cognitive impairments in schizophrenia and a therapeutic strategy.

Thyroid hormone concentrations in severely or critically ill patients with COVID-19

OBJECTIVE

COVID-19 is a new coronavirus infectious disease. We aimed to study the characteristics of thyroid hormone levels in patients with COVID-19 and to explore whether thyroid hormone predicts all-cause mortality of severely or critically ill patients.

METHODS

The clinical data of 100 patients with COVID-19, who were admitted to Wuhan Tongji Hospital from February 8 to March 8, 2020, were analyzed in this retrospective study. The patients were followed up for 6-41 days. Patients were grouped into non-severe illness and severe or critical illness, which included survivors and non-survivors. Multivariate Cox proportional hazards analysis was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality in association with continuous and the lower two quartiles of thyroid hormone concentrations in severely or critically ill patients.

RESULTS

The means of free T3 (FT3) were 4.40, 3.73 and 2.76 pmol/L in non-severely ill patients, survivors and non-survivors, respectively. The lower (versus upper) two quartiles of FT3 was associated with all-cause mortality HR (95% CI) of 9.23 (2.01, 42.28). The HR (95% CI) for all-cause mortality in association with continuous FT3 concentration was 0.41 (0.21, 0.81). In the multivariate-adjusted models, free T4 (FT4), TSH and FT3/FT4 were not significantly related to all-cause mortality. Patients with FT3 less than 3.10 pmol/L had increased all-cause mortality.

CONCLUSION

FT3 concentration was significantly lower in patients with severe COVID-19 than in non-severely ill patients. Reduced FT3 independently predicted all-cause mortality of patients with severe COVID-19.

System-on-chip upgrade of millimeter-wave imaging diagnostics for fusion plasma

Monolithic, millimeter wave "system-on-chip" technology has been employed in chip heterodyne radiometers in a newly developed Electron Cyclotron Emission Imaging (ECEI) system on the DIII-D tokamak for 2D electron temperature and fluctuation diagnostics. The system employs 20 horn-waveguide receiver modules each with customized W-band (75-110 GHz) monolithic microwave integrated circuit chips comprising a W-band low noise amplifier, a balanced mixer, a ×2 local oscillator (LO) frequency doubler, and two intermediate frequency amplifier stages in each module. Compared to previous quasi-optical ECEI arrays with Schottky mixer diodes mounted on planar antennas, the upgraded W-band array exhibits >30 dB additional gain and 20× improvement in noise temperature; an internal eight times multiplier chain is used to provide LO coupling, thereby eliminating the need for quasi-optical coupling. The horn-waveguide shielding housing avoids out-of-band noise interference on each module. The upgraded ECEI system plays an important role for absolute electron temperature and fluctuation measurements for edge and core region transport physics studies. An F-band receiver chip (up to 140 GHz) is under development for additional fusion facilities with a higher toroidal magnetic field. Visualization diagnostics provide multi-scale and multi-dimensional data in plasma profile evolution. A significant aspect of imaging measurement is focusing on artificial intelligence for science applications.

Development of an indirect ELISA based on glycoprotein B gene for detecting of Feline herpesvirus type 1

The study was aimed to develop an indirect enzyme-linked immunosorbent assay (ELISA), which can detect specifically Feline herpesvirus type 1 (FHV-1). The primers were designed based on the conserved sequence of FHV-1 glycoprotein B gene. The recombinant protein with reactogenicity was purified as coating antigen of the assay. The indirect ELISA, characterized by high sensitivity showed no cross-reaction with two types of feline virus, had detection limit at 1:2000 dilution. The positive rate of the assay, according to the determined cutoff value (0.25), was basically consistent with Feline Herpes Virus Antibody ELISA kit. In conclusion, the indirect ELISA with high repeatability and reproducibility can be used for detecting FHV-1, and can provide necessary support to related research.

Plasma fluoroacetic acid concentrations: Symptoms, hematological, and biochemical characteristics in patients with fluoroacetic acid poisoning in the emergency department

Fluoroacetic acid (FAcOH) was once a highly toxic rodenticide widely used in the world. In the past, studies on the toxicity of FAcOH have focused on animal experiments. The toxicity of FAcOH to humans and the changes of FAcOH in plasma have not been studied. Therefore, the present study aimed to describe the changes of plasma FAcOH concentrations, hematological, and biochemical characteristics in patients with FAcOH intoxication. According to clinical symptoms, 68 patients from the emergency department were divided into different groups: convulsion group, unconsciousness group, death group, and control groups. Plasma FAcOH concentrations, hematological, and biochemical parameters were investigated. Results demonstrated that patients in the convulsion group and the unconsciousness group had a significant increase (p < 0.01) in the level of neuron-specific enolase (NSE), creatine kinase MB (CKMB), glucose (GLU), and white blood cell count (WBC) and a significant decrease (p < 0.01) in serum potassium compared with the control group, respectively. Moreover, patients in the death group had a significant increase (p < 0.01) in the level of NSE, CKMB, N-terminal pro-brain natriuretic peptide, GLU, and WBC and a significant decrease (p < 0.01) in serum potassium and total calcium compared with the survival group. The concentrations of FAcOH in plasma in the convulsion group, the unconsciousness group, and the death group were 72.31 ± 42.29, 118.33 ± 55.41, and 163.78 ± 43.32 μg/mL, respectively. These changes and the plasma FAcOH concentrations may increase our understanding of the toxicity of FAcOH to humans and may help doctors to judge the clinical prognosis of patients with FAcOH intoxication.

Genetic analysis of skinfold thickness and its association with body condition score and milk production traits in Chinese Holstein population

The skin has many important roles in dairy cattle, and skinfold thickness could be used as an indicator of body fat deposition. The objectives of this study were to estimate genetic parameters of skinfold thickness and to explore its association with body condition score (BCS) and milk production traits in a Chinese Holstein population. Skinfold thicknesses over the neck (STN) and the last rib (STR), BCS, and test-day records of milk production traits were available for 6,416 lactating Holstein cows in the summers of 2015 and 2016 in Beijing, China. Multi-trait animal models were used to estimate variance and covariance components using the DMU software. The average STN was 7.15 ± 1.28 mm, and the average STR was 11.76 ± 1.95 mm (mean ± standard deviation). Estimated heritability was 0.13 ± 0.03 for STN and 0.26 ± 0.04 for STR. We detected a high genetic correlation (0.79 ± 0.08; heritability ± standard error) between STN and STR. Genetic correlations between skinfold thickness and BCS were low to moderate: 0.18 between STR and BCS, and 0.33 between STN and BCS. Genetic correlations between skinfold thickness and milk yield, milk fat percentage, and milk protein percentage were negligible, ranging from -0.02 to 0.15. Collectively, skinfold thickness is characterized as a trait with moderate heritability. Skinfold thickness is sensitive to changes in body condition or fat deposition across parities and lactation stages in milking cows, and we confirmed the complementary nature of skinfold thickness and BCS genetically as well as phenotypically by comparing their changing trends throughout lactation and across lactations. The use of skinfold thickness, together with BCS, can assist in the monitoring of changes in body fat deposition to achieve higher management precision.

Experimental study on the evolution of Peregrine breather with uniform-depth adverse currents

A series of laboratory experiments were performed to study the evolution of Peregrine breather (PB) in a wave flume in finite depth, and wave trains were initially generated in a region of quiescent water and then propagated into an adverse current region for which the current velocity strength gradually increased from zero to an approximately stable value. The PB is often considered as a prototype of oceanic freak waves that can focus wave energy into a single wave packet. In the experiment, the cases were selected with the relative water depths k_{0}h (k_{0} is the wave number in quiescent water and h is the water depth) varying from 3.11 through 8.17, and the initial wave steepness k_{0}a_{0} (a_{0} is the background wave amplitude) ranges between 0.065 and 0.120. The experimental results show the persistence of the breather evolution dynamics even in the presence of strong opposing currents. We have shown that the characteristic spectrum of the PB persists even on strong currents, thus making it a viable characteristic for prediction of freak waves. It was also found that the adverse currents tend to shift the focusing point upstream compared to the cases without currents. Furthermore, it was found that uniform-depth adverse currents can reduce the breather extension in time domain.

The function of dendritic cells in modulating the host response

Dendritic cells (DCs) are antigen-presenting cells that capture, process, and present antigens to lymphocytes to initiate and regulate the adaptive immune response. DCs detect bacteria in skin and mucosa and migrate into regional lymph nodes, where they stimulate antigen-specific T and B lymphocyte activation and proliferation. DCs direct CD4 T cells to differentiate to T-cell subsets such as T helper cells types 1, 2, and 17, and regulatory T cells. The periodontium is chronically exposed to oral bacteria that stimulate an inflammatory response to induce gingivitis or periodontitis. DCs play both protective and destructive roles through activation of the acquired immune response and are also reported to be a source of osteoclast precursors that promote bone resorption. FOXO1, a member of the forkhead box O family of transcription factors, plays a significant role in the activation of DCs. The function of DCs in periodontal inflammation has been investigated in a mouse model by lineage-specific deletion of FOXO1 in these cells. Deletion of FOXO1 reduces DC protective function and enhances susceptibility to periodontitis. The kinase Akt, phosphorylates FOXO1 to inhibit FOXO activity. Hence the Akt-FOXO1 axis may play a key role in regulating DCs to have a significant impact on periodontal disease.

Linear-shear-current modified Schrödinger equation for gravity waves in finite water depth

A nonlinear Schrödinger equation for the propagation of two-dimensional surface gravity waves on linear shear currents in finite water depth is derived. In the derivation, linear shear currents are assumed to be a linear combination of depth-uniform currents and constant vorticity. Therefore, the equation includes the combined effects of depth-uniform currents and constant vorticity. Next, using the equation, the properties of the modulational instability of gravity waves on linear shear currents are investigated. It is showed that shear currents significantly modify the modulational instability properties of weakly nonlinear waves. Furthermore, the influence of linear shear currents on Peregrine breather which can be seen as a prototype of freak waves is also studied. It is demonstrated that depth-uniform opposing currents can reduce the breather extension in both the time and spatial domain in intermediate water depth, but following currents has the adverse impact, indicating that a wave packets with freak waves formed on following currents contain more hazardous waves in finite water depth. However, the corresponding and coexisting vorticity can counteract the influence of currents. Additionally, if the water depth is deep enough, shear currents have negligible effect on the characteristics of Peregrine breathers.

Thymidylate synthase gene polymorphisms as important contributors affecting hepatocellular carcinoma prognosis

BACKGROUND

Thymidylate synthase (TYMS), a key rate-limiting enzyme in the folate metabolism, plays essential roles in the development of several malignancies including hepatocellular carcinoma (HCC). Nonetheless, the association of the single nucleotide polymorphisms (SNPs) in TYMS gene with the prognosis of Chinese HCC patients remains unknown.

METHODS

A total of 492 HCC patients who underwent surgery treatment were included in this study. Five functional SNPs (rs2847153, rs2853533, rs502396, rs523230, and rs9967368) in TYMS gene were genotyped using the iPLEX genotyping system. Multivariate Cox proportional hazards regression model and Kaplan-Meier curve were used to analyze the association of SNPs with survival and recurrence of HCC patients.

RESULTS

Two SNPs (rs523230 and rs9967368) in TYMS gene were significantly associated with the overall survival of HCC patients. Patients carrying homozygous variant genotype (VV) of rs523230 had significantly decreased risk of death (hazard ratio [HR], 0.68; 95% confidence interval [CI], 0.46-1.00; P=0.048) when compared with those carrying homozygous wild-type (WW) or heterozygous (WV) genotypes, while patients carrying WV+VV genotype of rs9967368 had significantly increased risk of death (HR, 1.46; 95% CI, 1.05-2.04; P=0.026) when compared with those carrying WW genotypes. Cumulative effect analysis showed a significant dose-dependent effect of unfavorable SNPs on OS.

CONCLUSIONS

Our study for the first time demonstrates the association of SNPs in TYMS gene and clinical outcome of HCC, suggesting that rs523230 and rs9967368 in TYMS gene might be used to predict clinical outcome of Chinese HCC patients.

Real-time shear wave elastrography and APRI index for evaluating autoimmune hepatitis fibrosis

The objective of this study was to investigate the significance of real-time supersonic shear imaging (SSI) and serum biochemical index in evaluating the degree of autoimmune hepatitis fibrosis. Retrospective analysis was carried out to study 291 cases of patients with autoimmune hepatitis, and discuss the value of SSI application, APRI index and bilirubin on autoimmune hepatitis. The area under the receiver operating characteristic curve (AUROC) was taken for statistical analysis to determine its diagnostic accuracy. In the high degree of hepatic fibrosis, the hepatic SSI measured value of autoimmune hepatitis positively correlated to ALT, AST, APRI ratio, AST and AST/ALT. The SSI measured value significantly and positively correlated to the degree of hepatic fibrosis (r=0.598, p=0 less than 0.01). In chronic hepatic fibrosis, the elasticity values of AIH, PBC, AIH-PBC overlap syndrome (OS) were in a rising trend, and the difference in the elasticity value of each fibrosis stage was statistically significant (P less than 0.01). Hepatic SSI measured value was employed to respectively detect the AUROC of S3 stage and S4 stage for AIH, PBC, and AIR-PBC OS groups, which resulted as being higher than the APRI index detected in S3 stage and S4 stage. SSI measured index had better diagnostic significance than APRI index on hepatic fibrosis for AIH, PBC and AIH-PBC OS groups.

Hepatic fibrosis and supersonic shear imaging in patients with different etiological chronic hepatic diseases

The objective of the present study was to investigate whether hepatic fibrosis difference of supersonic shear imaging (SSI) value existed in patients with different etiological chronic hepatic diseases. Retrospective analysis was used to study chronic hepatitis. All the subjects were diagnosed by shear wave elastography and percutaneous liver biopsy. The shear moduli were analyzed to check whether any difference existed between groups. For the chronic hepatitis B, autoimmune hepatitis and fatty hepatitis, the shear moduli in S0 stage were (8.50±3.1)kPa, (9.41±2.5)kPa, (8.97±3.8)kPa; the shear moduli in S1 stage were (9.54±3.0)kPa, (10.42±5.1)kPa, (9.51±4.6)kPa; the shear moduli in S2 stage were (11.77±4.8) kPa, (13.25±5.6)kPa, (11.03±6.0)kPa; the shear moduli in S3 stage were (14.96±6.1)kPa, (19.03±7.8) kPa, (15.38±7.8)kPa; the shear moduli in S4 stage were (20.36±7.5)kPa, (24.99±9.5)kPa, (19.53±5.6)kPa. Shear wave elastography could measure the different etiological chronic hepatic diseases.

In vitro Selection of Human Immunodeficiency Virus Type 1 Resistant to Ro 31-8959 Proteinase Inhibitor

Human immunodeficiency virus type I (HIV-1) resistant to the proteinase inhibitor Ro 31–8959 has been obtained by growing HIV-IIIB in C8166 cell cultures in the presence of inhibitory concentrations of the drug.

Ro 31-8959-resistant HIV-1 obtained after five passages in the presence of the drug was capable of replicating, as measured by infectious virus yield, in the presence of concentrations of Ro 31-8959 able to inhibit completely the replication of the parental HIV-IIIB.

Cloning of the Ro 31–8959-resistant viral preparations revealed that a number of different strains of HIV-1 with various degrees of sensitivity to Ro 31–8959 emerged during propagation of HIV-IIIB in C8166 cells in the presence of the drug. The most resistant strain shows an ID50 value of 21.8 nM that is 13.2 fold higher than the value observed in HIV-IIIB infected C8166 cells.