Correlation of Apparent Diffusion Coefficient With Proliferation and Apoptotic Indexes in a Murine Model of Fibrosarcoma: Comparison of Four Methods for MRI Region of Interest Positioning.

BACKGROUND: Diffusion-weighted imaging (DWI) has demonstrated great potential in predicting the expression of tumor cell proliferation and apoptosis indexes. PURPOSE: To evaluate the impact of four region of interest (ROI) methods on interobserver variability and apparent diffusion coefficient (ADC) values and to examine the correlation of ADC values with Ki-67, Bcl-2, and P53 labeling indexes (LIs) in a murine model of fibrosarcoma. STUDY TYPE: Prospective, animal model. ANIMAL MODEL: A total of 22 female BALB/c mice bearing intramuscular fibrosarcoma xenografts. FIELD STRENGTH/SEQUENCE: A 3.0 T/T1-weighted fast spin-echo (FSE), T2-weighted fast relaxation fast spin-echo, and DWI PROPELLER FSE sequences. ASSESSMENT: Four radiologists measured ADC values using four ROI methods (oval, freehand, small-sample, and whole-volume). Immunohistochemical assessment of Ki-67, Bcl-2, and P53 LIs was performed. STATISTICAL TESTS: Interclass correlation coefficient (ICC), one-way analysis of variance followed by LSD-t post hoc analysis, and Pearson correlation test were performed. The statistical threshold was defined as a P-value of <0.05. RESULTS: All ROI methods for ADC measurements showed excellent interobserver agreement (ICC range, 0.832-0.986). The ADC values demonstrated significant differences among the four ROI methods. The ADC values for oval, freehand, small-sample, and whole-volume ROI methods showed a moderately negative correlation with Ki-67 (r = -0.623; r = -0.629; r = -0.642, and r = -0.431) and Bcl-2 (r = -0.590; r = -0.597; r = -0.659, and r = -0.425) LIs, but no correlation with P53 LI (r = 0.364, P = 0.104; r = 0.350, P = 0.120; r = 0.379, P = 0.091; r = 0.390, P = 0.080). DATA CONCLUSION: The ADC value can be used to evaluate cell proliferation and apoptosis indexes in a murine model of fibrosarcoma, employing the small-sample ROI as a reliable method. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 3.

Correlation between IVIM parameters and microvessel architecture: direct comparison of MRI images and pathological slices in an orthotopic murine model of rhabdomyosarcoma.

OBJECTIVE: This study aimed to explore the correlation between intravoxel incoherent motion (IVIM) parameters and microvessel architecture (microvessel density (MVD), vasculogenic mimicry (VM), and pericyte coverage index (PCI)) in an orthotopic murine model of rhabdomyosarcoma. METHODS: The murine model was established by injecting rhabdomyosarcoma-derived (RD) cells into the muscle. Nude mice underwent routine magnetic resonance imaging (MRI) and IVIM examinations with ten b values (0, 50, 100, 150, 200, 400, 600, 800, 1000, and 2000 s/mm2). D, D*, and f values were calculated with the ADW4.7 workstation. MRI images and pathological slices were directly compared to ensure that radiology parameters accurately reflect pathology. MVD, VM, PCI, and cellularity were obtained by histological analysis. The correlations were assessed between IVIM parameters (D, D*, f, and fD* values) and pathological markers (MVD, VM, PCI, and cellularity). RESULTS: The average of D, D*, f, and fD* values were 0.55 ± 0.07 × 10-3 mm2/s, 5.25 ± 0.73 × 10-3 mm2/s, 13.39 ± 7.68%, and 0.73 ± 0.49 × 10-3 mm2/s, respectively. The average of MVD, VM, PCI, and cellularity were 41.91 ± 10.98, 1.16 ± 0.83, 0.49 ± 0.18, and 39.15 ± 9.00%. D*, f, and fD* values showed a positive correlation with MVD separately, while the D value did not correlate with MVD. D value negatively correlated to VM moderately, and other parameters did not associate with VM. D* and fD* values were positively correlated with PCI, but no correlation was observed between other parameters and PCI. CONCLUSIONS: IVIM may evaluate the tumor microvessel architecture. D*, f, and fD* may reflect the endothelial lining blood vessel; D could indirectly reflect the VM; D* and fD* could reflect PCI(the normal degree of the tumor blood vessel). CLINICAL RELEVANCE STATEMENT: An intravoxel incoherent motion may be useful in assessing rhabdomyosarcoma microvessel structure to predict the target and effectiveness of anti-angiogenic therapy. KEY POINTS: • IVIM may be used to evaluate the tumor microvessel architecture in the mouse rhabdomyosarcoma model. • The MRI-pathology control method achieves correspondence between MRI slices and pathology slices, which ensures the consistency of the ROI of MRI and the pathology observation region.

Soft tissue sarcoma: intravoxel incoherent motion and diffusion kurtosis imaging parameters correlate with the histological grade and Ki-67 expression.

BACKGROUND: Accurate prediction of the histological grade and Ki-67 expression of soft tissue sarcoma (STS) before surgery is essential for the subsequent diagnosis, treatment, and prognostic evaluation of patients. PURPOSE: To evaluate intravoxel incoherent motion (IVIM) and diffusion kurtosis imaging (DKI) in predicting the histological grade and Ki-67 expression of STS. MATERIAL AND METHODS: A total of 40 patients underwent 3-T MRI, including conventional sequences; IVIM and DKI parameters were obtained. All patients were divided into a low-grade (grade 1 and grade 2) group and a high-grade (grade 3) group through pathological analysis. Ki-67 expression of each lesion was calculated. Chi-square test, independent sample t-test, Mann-Whitney U test, Pearson, Spearman, and receiver operating characteristic curve analysis were performed. RESULTS: There were 17 patients in the low-grade group and 23 in the high-grade group. Ki-67 expression was in the range of 10%-80%. D value was inversely correlated with Ki-67 expression. MK value showed a moderate positive correlation with Ki-67 expression. Regarding histological grading, only the peritumoral enhancement was statistically different between low- and high-grade STS on conventional MRI (P=0.024). The high-grade group had significantly higher MK value and lower D and MD value than the low-grade group. MK value showed the best diagnostic performance. The combination of MK and MD yielded the highest specificity (88.24%), and the combination of D, MK, and MD yielded the best area under the curve value (0.841) and sensitivity (95.65%). CONCLUSION: IVIM and DKI parameters were correlated with Ki-67 expression and could help differentiate between low- and high-grade STS.

Correlations between DWI, IVIM, and HIF-1α expression based on MRI and pathology in a murine model of rhabdomyosarcoma.

PURPOSE: To investigate the correlation between DWI, intravoxel incoherent motion (IVIM), and hypoxia-inducible factor 1-alpha (HIF-1α) expression in a nude mouse model of rhabdomyosarcoma based on imaging and pathological comparisons. METHODS: Human rhabdomyosarcoma-derived (RD) cells were inoculated into the right thigh muscle of 20 BALB/c female nude mice. Mice were imaged using 3.0 Tesla MRI system. T1 -weighted imaging, T2 -weighted imaging, DWI, and IVIM images were obtained. ADW4.7 (GE Healthcare, ChicagoAQ34, IL, USA) was used for image processing of ADC, Dslow , Dfast , and f values. All parameter values were independently analyzed by 2 observers. Immunohistochemistry of HIF-1α was performed. We used a specific image-pathology comparison method to ensure correct overlap between the image plane and the pathological section. Mann-Whitney U test or independent sample t test, Pearson or Spearman correlation test, the intragroup correlation coefficient, Kolmogorov-Smirnov test, and receiver operating characteristic curve were used. The correlation between DWI and intravoxel incoherent motion parameter values and HIF-1α expression was determined. RESULTS: There were 10 mice in the low-expression group and 7 in the high-expression group. The ADC and Dslow values were negatively correlated with HIF-1α with correlation coefficients of -0.491 and - 0.702 (P = 0.045 and 0.002). The f value positively correlated with HIF-1α expression (r = 0.485, P = 0.048). ADC, Dslow , and f were significantly different between the high-HIF-1α expression tumors and the low-HIF-1α expression tumors. ADC showed the best predictive performance among all parameters (area under the curve = 0.652, sensitivity = 83.3%, specificity = 63.6%). CONCLUSION: The parameter values of DWI and intravoxel incoherent motion can be used to evaluate the expression of HIF-1α in rhabdomyosarcoma. ADC, Dslow , and f value showed correlation with the expression of HIF-1α.

DWI and IVIM Imaging in a Murine Model of Rhabdomyosarcoma: Correlations with Quantitative Histopathologic Features.

BACKGROUND: High cellularity and abnormal interstitial structures are some of the unfavorable factors that affect the treatment outcomes and survival of rhabdomyosarcoma (RMS) patients. PURPOSE: To explore the correlation between diffusion-weighted imaging (DWI) and intravoxel incoherent motion (IVIM) with quantitative histopathologic features in a murine model of RMS. STUDY TYPE: Prospective. ANIMAL MODEL: Murine model of RMS (31 female BALB/c nude mice). FIELD STRENGTH/SEQUENCE: 3.0 T; fast spin-echo (FSE) T1-weighted imaging, fast relaxation fast spin-echo (FRFSE) T2-weighted imaging, DWI PROPELLER FSE imaging sequence, and IVIM echo planar imaging sequence; 10 different b-values (0, 50, 100, 150, 200, 400, 600, 800, 1000, and 1200 s/mm2 ). ASSESSMENT: Magnetic resonance imaging (MRI) was performed after 30-45 days of implantation. The following MRI parameters were calculated: apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f). Histopathologic features, which contained nuclear, cytoplasmic, and stromal fractions, and the nuclear-to-cytoplasmic ratio within the tumor were measured using image-based segmentation. STATISTICAL TESTS: Pearson's correlation, multiple linear regression analysis, and receiver operating characteristic curve analysis were performed. A P < 0.05 was considered statistically significant. RESULTS: The ADC value showed moderate negative correlation with nuclear fraction (r = -0.540), and moderate positive correlation with stroma fraction (r = 0.474). The D value showed moderate negative correlation with nuclear fraction (r = -0.491), and moderate positive correlation with stroma fraction (r = 0.421). The f value showed a moderate negative correlation with stroma fraction (r = -0.423). The D value showed the best diagnostic ability. The optimal cut-off D value of 0.460 was associated with 77.8% sensitivity and 68.2% specificity (area under the curve, 0.747). DATA CONCLUSION: The ADC, D, and f values obtained from DWI and IVIM images showed moderate correlation with the quantitative histopathologic features in a murine model of RMS. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY STAGE: 3.

An Update in Imaging Evaluation of Histopathological Grade of Soft Tissue Sarcomas Using Structural and Quantitative Imaging and Radiomics.

Over the past two decades, considerable efforts have been made to develop non-invasive methods for determining tumor grade or surrogates for predicting the biological behavior, aiding early treatment decisions, and providing prognostic information. The development of new imaging tools, such as diffusion-weighted imaging, diffusion kurtosis imaging, perfusion imaging, and magnetic resonance spectroscopy have provided leverage in the diagnosis of soft tissue sarcomas. Artificial intelligence is a new technology used to study and simulate human thinking and abilities, which can extract and analyze advanced and quantitative image features from medical images with high throughput for an in-depth characterization of the spatial heterogeneity of tumor tissues. This article reviews the current imaging modalities used to predict the histopathological grade of soft tissue sarcomas and highlights the advantages and limitations of each modality. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY: Stage 2.

Genome sequencing of 320 Chinese children with epilepsy: a clinical and molecular study.

The aim of this study is to evaluate the diagnostic value of genome sequencing in children with epilepsy, and to provide genome sequencing-based insights into the molecular genetic mechanisms of epilepsy to help establish accurate diagnoses, design appropriate treatments and assist in genetic counselling. We performed genome sequencing on 320 Chinese children with epilepsy, and interpreted single-nucleotide variants and copy number variants of all samples. The complete pedigree and clinical data of the probands were established and followed up. The clinical phenotypes, treatments, prognoses and genotypes of the patients were analysed. Age at seizure onset ranged from 1 day to 17 years, with a median of 4.3 years. Pathogenic/likely pathogenic variants were found in 117 of the 320 children (36.6%), of whom 93 (29.1%) had single-nucleotide variants, 22 (6.9%) had copy number variants and two had both single-nucleotide variants and copy number variants. Single-nucleotide variants were most frequently found in SCN1A (10/95, 10.5%), which is associated with Dravet syndrome, followed by PRRT2 (8/95, 8.4%), which is associated with benign familial infantile epilepsy, and TSC2 (7/95, 7.4%), which is associated with tuberous sclerosis. Among the copy number variants, there were three with a length <25 kilobases. The most common recurrent copy number variants were 17p13.3 deletions (5/24, 20.8%), 16p11.2 deletions (4/24, 16.7%), and 7q11.23 duplications (2/24, 8.3%), which are associated with epilepsy, developmental retardation and congenital abnormalities. Four particular 16p11.2 deletions and two 15q11.2 deletions were considered to be susceptibility factors contributing to neurodevelopmental disorders associated with epilepsy. The diagnostic yield was 75.0% in patients with seizure onset during the first postnatal month, and gradually decreased in patients with seizure onset at a later age. Forty-two patients (13.1%) were found to be specifically treatable for the underlying genetic cause identified by genome sequencing. Three of them received corresponding targeted therapies and demonstrated favourable prognoses. Genome sequencing provides complete genetic diagnosis, thus enabling individualized treatment and genetic counselling for the parents of the patients. Genome sequencing is expected to become the first choice of methods for genetic testing of patients with epilepsy.

The diagnostic accuracy of intravoxel incoherent motion and diffusion kurtosis imaging in the differentiation of malignant and benign soft-tissue masses: which is better?

BACKGROUND: It is difficult for conventional magnetic resonance imaging (MRI) to distinguish benign soft-tissue masses (STMs) from malignant masses. PURPOSE: To quantitatively compare the diagnostic value of intravoxel incoherent motion (IVIM) and diffusion kurtosis imaging (DKI) in STMs. MATERIAL AND METHODS: The data from 58 patients with STMs were retrospectively analyzed. The GE Discovery 3.0-T MRI scanner was used to acquire conventional MRI sequences, IVIM, and DKI images. The chi-square test, independent sample t-test, and Mann-Whitney U tests were used to compare the differences between conventional MRI features, IVIM, and DKI parameters (Dslow, Dfast, f, mean kurtosis [MK], and mean diffusivity [MD]) between the benign and malignant groups. Receiver-operating characteristic (ROC) curve analysis was also performed. RESULTS: Tumor size and depth are statistically different in STTs. Dslow, MK, and MD values in the malignant groups are significantly lower than the benign groups (P < 0.05). However, Dfast and f values are not statistically different between the two groups. The area under the curve (AUC) of Dslow value (0.859) is higher than MD (0.765) and MK (0.676) values for identifying benign and malignant STMs. The Dslow value showed the best specificity (82.93%). The sensitivity and specificity of IVIM and DKI parameters are higher than that of conventional MRI sequences. CONCLUSION: IVIM and DKI can be used to distinguish between benign and malignant STMs, with Dslow as the most meaningful parameter.

Targeted Next-Generation Sequencing Reveals a Large Novel ß-Thalassemia Deletion that Removes the Entire HBB Gene.

ß-Thalassemia (ß-thal) is one of the most common monogenic recessive inherited diseases worldwide. The mutation spectrum of ß-thal has been increasingly broadened by various genetic testing methods. The discovery and identification of novel and rare pathogenic thalassemia variants enable better disease prevention, especially in high prevalence regions. In this study, a Chinese thalassemia family with an unclear etiology was recruited to the Thalassemia Screening Program. Blood samples collected from them were primarily screened by hematology analysis and clinical routine genetic screening. Subsequently, targeted next-generation sequencing (NGS) and Sanger sequencing were performed to find and identify a novel deletion variant. The deletion, discovered by targeted NGS, was validated through real-time quantitative polymerase chain reaction (qPCR). First, a large novel ß-thal deletion (3488 bp) related to a high Hb F level, NC_000011.9: g.5245533_5249020del (Chongqing deletion) (GRCh37/hg19), was found and identified in the proband and her mother. The deletion removed the entire ß-globin gene and led to absent ß-globin (ß0). We then validated this large novel deletion in the proband and her mother by qPCR. We first discovered and identified a large novel ß-thal deletion related to elevated Hb F level, it helps broaden the spectrum of pathogenic mutants that may cause ß-thal intermedia (ß-TI) or ß-thal major (ß-TM), paving the way for effective thalassemia screening. Next-generation sequencing has the potential of finding rare and novel thalassemia mutants.

[Quality evaluation of Curcumae Radix from different origins based on UPLC characteristic chromatogram, multicomponent content, and chemometrics].

In this study, UPLC was used to establish the characteristic chromatograms of Curcumae Radix from different origins(LSYJ, WYJ, HSYJ, and GYJ) and the content determination method of 11 chemical components. The evaluation of characteristic chromatogram similarity, cluster analysis(CA), principal component analysis(PCA), and orthogonal partial least square discriminant analysis(OPLS-DA) were combined to evaluate the quality of Curcumae Radix from four origins. LSYJ, WYJ, HSYJ, and GYJ showed 15, 17, 15, and 10 characteristic peaks, respectively, and 8 of the peaks were identified. The characteristic chromatograms of Curcumae Radix samples(except for GYJ07) from the same origin showed the similarity greater than 0.854. The 11 chemical components had different content among the samples from four origins. Curcumenol, furanodienone, and isocurcumenol were rich in LSYJ; hydroxyisogermafurenolide, curdione, and furanodiene had high content in WYJ; gemacrone, ß-elemene, bisdemethoxycurcumin, demethoxycurcumin, and curcumin were rich in HSYJ; all the components had low content in GYJ. The chemometric analysis showed that CA, PCA, and OPLS-DA could accurately classify the four origins of Curcumae Radix into four categories, and five different quality markers, namely furanodienone, curcumenol, curdione, hydroxyisogermafurenolide, and furanodiene, were screened out by OPLS-DA. UPLC in combination with multicomponent content determination is simple, rapid, reproducible, and specific, which can provide reference for the quality control and identification of Curcumae Radix from four origins.

Copper-Catalyzed Cascade 1,4-Addition/Annulation/Hydrolysis of Propargylamines with 2-Hydroxynaphthalene-1,4-diones: Direct Formation of 12-Phenacyl-11H-benzo[b]xanthenes.

A novel and versatile approach to construct 12-phenacyl-11H-benzo[b]xanthene-6,11(12H)-dione derivatives through copper-catalyzed cascade reaction of propargylamines with 2-hydroxynaphthalene-1,4-diones has been developed. The procedure is proposed to go through a sequence of 1,4-conjugate addition, intramolecular nucleophilic addition/dehydration, and hydrolysis of alkyne followed by an enol-ketone tautomerization. The reaction provides a new and highly efficient method for the synthesis of 12-phenacyl-11H-benzo[b]xanthene-6,11(12H)-diones by formation of three new bonds and one heterocycle from readily available starting materials in good to high yields (70-88%) with broad functional group compatibility in a single step.

Dynamics of Detection of Anti-SARS-CoV-2 IgG/IgM and SARS-CoV-2 RNA in Respiratory Tract Specimens in 48 COVID-19 Patients.

BACKGROUND: The rapid spread of pneumonia caused by SARS-CoV-2 has seriously threatened people. In this study, we detected the expression of anti-SARS-CoV-2 IgG/IgM and respiratory tract SARS-CoV-2 RNA in patients with COVID-19 and explored the correlation and clinical significance between SARS-CoV-2 antibody and respiratory SARS-CoV-2 RNA. METHODS: From March 5, 2020 to April 28, 2020, 48 cases with COVID-19 diagnosed in Beijing Xiaotangshan Hospital were enrolled. SARS-CoV-2 RNAs were detected by real-time fluorescence RT-PCR method. Serum SARS-CoV-2 IgG/IgM antibodies were determined by colloidal gold immunochromatography. The statistical analysis was performed using chi-squared test. RESULTS: In all the patients, SARS-CoV-2 RNA among 270 upper respiratory tract (nasal or throat swabs) samples, 71 lower respiratory tract (sputum) samples, and anti-SARS-CoV-2 IgM/IgG antibodies in 123 serum samples were detected during the hospitalization period. The positive rate of anti-SARS-CoV-2 IgG was significantly higher than that of anti-SARS-CoV-2 IgM within the first week after symptom onset (p < 0.05). The positive rate of anti-SARS-CoV-2 IgG was also significantly higher than that of anti-SARS-CoV-2 IgM during day 8 - 30 after symptom onset (p < 0.01). The positive rate of SARS-CoV-2 RNA in the lower respiratory tract specimens (64.8%, 46/71) was significantly higher than that in the upper respiratory tract (46.7%, 126/270) (p < 0.05). The positive rate (100%, 4/4) of SARS-CoV-2 RNA detection in the lower respiratory tract specimens before IgG seroconversion was significantly higher than that of the positive rate (59.3%, 32/54) after IgG seroconversion (p < 0.01). The positive rate (72.2%, 57/79) of SARS-CoV-2 RNA detection in the upper respiratory tract specimens before IgG seroconversion was significantly higher than that of the positive rate (30.7%, 39/127) after IgG seroconversion (p < 0.01). CONCLUSIONS: Anti-SARS-CoV-2 IgG might be detected within the first week after symptom onset. The application of SARS-CoV-2 antibody (IgG/IgM) detection is important for the suspected cases of SARS-CoV-2 infection with negative SARS-CoV-2 RNA results. The positive rate of SARS-CoV-2 RNA detection in the lower respiratory tract specimens was significantly higher than that in the upper respiratory tract. Sputum detection is recommended for the detection of SARS-CoV-2 RNA. Using lower respiratory tract specimens may reduce the false negative PCR tests. The detection of SARS-CoV-2 RNA can be improved by investigating follow-up specimens over time.

A Novel Mutation at HBA1: c.349G>T Causing α-Thalassemia in a Chinese Family.

α-Thalassemia (α-thal) is one of the most common genetic diseases in Southern China. Although more than 300 α-thal mutations have been reported in the world, the mutation spectrum is still not comprehensive. In this study, a novel mutation (HBA1: c.349G>T) in a newborn (proband) was first found by next-generation sequencing (NGS). Subsequently, hematological analysis and thalassemia genetic testing were performed for the family members. The results showed that both the proband and her mother were heterozygotes for this novel mutation and presented abnormal hematological indices. Based on the features observed in clinical practice, this novel mutation was considered as a type of α-thal variation.

Comparative pharmacokinetic analysis of raw and steamed Panax notoginseng roots in rats by UPLC-MS/MS for simultaneously quantifying seven saponins.

CONTEXT: After being steamed, the restorative effects of Panax notoginseng (Burk.) F. H. Chen (Araliaceae) will be strengthened. However, the underlying mechanism remains elusive. OBJECTIVE: To compare the pharmacokinetics of ginsenosides Rg1, Rb1, Rd, Re, Rg5, Rk1, notoginsenoside R1 (GRg1, GRb1, GRd, GRe, GRg5, GRk1 and NGR1) in the raw and steam-processed P. notoginseng (RPN and SPN). MATERIALS AND METHODS: The pharmacokinetics of seven components after oral administration of SPN and RPN extracts (1.0 g/kg) were investigated, respectively, in SD rats (two groups, n = 6) using UPLC-MS/MS. RESULTS: The approach elicited good linear regression (r2 > 0.991). The accuracy, precision and stability were all within ± 15%. The extraction recoveries and matrix effects were 75.0-100.8% and 85.1-110.3%, respectively. Compared with the RPN group, AUC0-t of GRg1 (176.63 ± 42.49 ng/h/mL), GRb1 (5094.06 ± 1453.14 ng/h/mL), GRd (1396.89 ± 595.14 ng/h/mL), and NGR1 (135.95 ± 54.32 ng/h/mL), along with Cmax of GRg1 (17.41 ± 5.43 ng/mL), GRb1 (361.48 ± 165.57 ng/mL), GRd (62.47 ± 33.65 ng/mL) and NGR1 (23.97 ± 16.77 ng/mL) decreased remarkably with oral administration of the SPN extracts, while GRe showed no significantly difference. Of note, GRg5 and GRk1 could not be detected in the plasma. CONCLUSIONS: Influence of the processing reduced the systemic exposure levels to GRg1, GRb1, GRd and NGR1. It is the first report of comparative pharmacokinetic study of multiple saponins analysis after oral administration of RPN and SPN extract, which might be helpful for further studies on its steam-processing mechanism.

DWI and IVIM are predictors of Ki67 proliferation index: direct comparison of MRI images and pathological slices in a murine model of rhabdomyosarcoma.

OBJECTIVES: The purpose of this study was to investigate the correlation of diffusion-weighted imaging (DWI) and intravoxel incoherent motion (IVIM) with the Ki67 proliferation index in a murine model of rhabdomyosarcoma. METHODS: The rhabdomyosarcoma model was established by injecting RD cells into the right hind flank of nude mice. The mice underwent 3.0T magnetic resonance imaging (MRI), including DWI and IVIM. The apparent diffusion coefficient (ADC), D, D*, and f were calculated with the ADW4.7 workstation. A specialized method was employed to ensure the pathological sections corresponded to the correct MRI slices. The Ki67 proliferation index was analyzed by immunohistochemistry, and any possible correlations were assessed between the DWI and IVIM parameters and Ki67 proliferation index. RESULTS: Twenty-seven rhabdomyosarcoma mice were established successfully. After 46 days, the average tumor volume reached 1094.78 ± 678.77 mm3. The average ADC, D, and D* values were 1.0470 ± 0.2036 × 10-3 mm2/s, 0.7237 ± 0.0971 × 10-3 mm2/s, and 4.8497 ± 1.6293 × 10-3 mm2/s, respectively. The range in f values was 0.102-0.229. The ADC and D values showed a moderate negative correlation with the Ki67 proliferation indexes (r = - 0.543, p = 0.003; r = - 0.491, p = 0.009, respectively). In addition, the f value showed a weak negative correlation with the Ki67 proliferation indexes (r = - 0.151, p = 0.451), while the D* value showed no association with the Ki67 proliferation indexes (r = - 0.037, p = 0.853). CONCLUSIONS: The ADC value of DWI, along with the D value of IVIM, may be reflective of Ki67 proliferation indexes in murine models of rhabdomyosarcoma. KEY POINTS: • DWI and IVIM parameters are correlated with Ki67 proliferation indexes in rhabdomyosarcoma mouse models. • A specialized method ensured a strong correlation between pathological sections and MRI slices, resulting in a robust radiological-pathological correlation.

SPR immunosensor combined with Ti4+@TiP nanoparticles for the evaluation of phosphorylated alpha-synuclein level.

A highly sensitive and specific surface plasmon resonance (SPR) method using one anti-alpha-synuclein antibody (anti-αS) and titanium phosphate nanoparticles (Ti4+@TiP) was developed for quantitative evaluation of phosphorylated αS level which was defined by the ratio of p-αS to total alpha-synuclein (t-αS) (p-αS/t-αS). The close affinities of anti-αS to αS (0.975 pM-1) and p-αS (0.938 pM-1) were obtained. Based on this fact , both αS forms were simultaneously captured and the t-αS was quantified using the anti-αS immobilized Au chip. With the selective recognition of Ti4+@TiP nanoparticles, the p-αS was quantified. The dynamic ranges of our method were 1.0~20.0 pg mL-1 for the detection of t-αS and 0.1~10.0 pg mL-1 for that of p-αS. The analysis of αS- and p-αS-spiked artificial cerebrospinal fluid samples revealed the high accuracy of the method. Furthermore, the concentrations of αS and p-αS in clinical CSF samples collected from three healthy donors were determined and displayed a high correlation with the results from a commercial ELISA kit, confirming the viability and of the proposed method. The method is convenient, economical, and practical for the evaluation of phosphorylated αS level with high sensitivity and selectivity. It is of great significance for the early diagnosis of PD and the evaluation of PD progression.Graphical abstract.

Coimmunocapture and Electrochemical Quantitation of Total and Phosphorylated Amyloid-ß40 Monomers.

Phosphorylated proteins play important roles in the pathogenesis of Alzheimer's disease (AD). The most abundant constituent in AD's brain deposit is the amyloid-ß40 peptide (Aß40). Based on it, the degree of phosphorylated Aß40 in body fluids (e.g., cerebrospinal fluid, CSF), which is defined by the ratio of phosphorylated Aß40 to total Aß40 (pAß40/tAß40), is anticipated to be an index for early diagnosis of AD. The major challenge in pAß40/tAß40 detection is the large concentration difference between two Aß40 forms in the real samples, which usually requires multichannel equipment and complicated detection process. In this paper, we revealed the unexpected close affinities of the anti-Aß40 antibody to Aß40 (40.2 nM-1) and to pAß40 (42.3 nM-1). Based on it, a convenient coimmunocapture and electrochemical quantitation of tAß40 and pAß40 was achieved on an anti-Aß40 antibody immobilized Au electrode (anti-Aß40/Au). Once Aß40 and pAß40 were synchronously captured on the anti-Aß40/Au electrode, the tAß40 levels in CSF samples were quantified with electrochemical impedance spectroscopy. With the signal amplification from Cd2+/Ti4+-functionalized titanium phosphate nanospheres (Cd2+/Ti4+@TiP) which was selective conjugated to pAß40, concentrations of low abundant pAß40 as low as 1 fM were readily measured by square wave voltammetry. Our results reveal that despite the concentrations of tAß40 and pAß40 fluctuate in each individual case, the concentration ratios of pAß40/tAß40 in CSF samples from AD patients are significant larger than those from healthy donors. It demonstrates that the degree of phosphorylated Aß40 is hopeful to be an effective index for evaluating the AD progress and improving the accuracy of clinic AD diagnosis.

Greater negative lymph node count predicts favorable survival of patients with breast cancer in the setting of neoadjuvant chemotherapy and mastectomy.

Aim: Adequate lymph node evaluation is recommended in patients with malignant tumors. However, the role of negative lymph nodes (NLNs) remains unclear in breast cancer (BC), especially in patients who have received neoadjuvant chemotherapy and mastectomy. Materials & methods: A total of 435 patients were included in the analysis. On multivariate analysis, NLN count was an independent predictor of 5 year disease-free survival and 5 year overall survival. Results: Patients with NLN count <10 showed significantly worse 5 year disease-free survival than those with NLN count ≥10 (34.8 and 78.2%; p = 0.000); the corresponding 5 year overall survival rates were also significantly different (52.0 and 82.7%; p = 0.000). Conclusion: This is the first study that confirms the relationship between NLN count and prognosis of patients in the setting of neoadjuvant chemotherapy and mastectomy. More NLNs imply better prognosis.

Next-generation sequencing improves molecular epidemiological characterization of thalassemia in Chenzhou Region, P.R. China.

OBJECTIVES: Thalassemia is a highly prevalent monogenic inherited disease in southern China. It is important to collect epidemiological data comprehensively for proper prevention and treatment. METHODS: In this study, blood samples collected from 15 807 residents of Chenzhou were primarily screened by hematological tests. A total of 3973 samples of suspected thalassemia carriers were further characterized by combined next-generation sequencing (NGS) and Gap-PCR. RESULTS: In total, 1704 subjects were diagnosed as thalassemia carriers with a total prevalence rate of 10.78%, including 943 α-thalassemia carriers, 708 ß-thalassemia carriers, and 53 composite α and ß-thalassemia carriers. The prevalence rates of α-thalassemia, ß-thalassemia, and composite α and ß-thalassemia were 5.97%, 4.48%, and 0.34%, respectively. Meanwhile, we characterized 19 α-thalassemia variations and 21 ß-thalassemia variations in thalassemia carriers. Approximately 2.88% of thalassemia carriers would be missed by traditional genetic analysis. In addition, four novel thalassemia mutations and one novel abnormal hemoglobin mutation were identified. CONCLUSIONS: Our data suggest a high prevalence of thalassemia and a diverse spectrum of thalassemia-associated variations in Chenzhou. Also, combined NGS and Gap-PCR is an effective thalassemia screening method. Our findings might be helpful for prevention and treatment of thalassemia in this region.

Optimization of Ultrasonic-Assisted Simultaneous Extraction of Three Active Compounds from the Fruits of Forsythia suspensa and Comparison with Conventional Extraction Methods.

An efficient ultrasonic-assisted extraction (UAE) method was developed for simultaneous extraction of three active compounds, forsythiaside A (FSA), phillyrin (PHI) and rutin (RT), from the fruits of Forsythia suspensa. The effects of various factors including a binary mixed solvent of methanol/water and ethanol/water, the pH of the solvent, particle size, temperature, solvent to material ratio, ultrasonic input power and extraction time on UAE were investigated in detail. The mass transfer mechanism of UAE using different mixed solvents was further explained by comparison with the maceration extraction method. The response surface methodology was used to optimize the experimental variables including ethanol concentration, solvent to material ratio and extraction time. The optimized conditions for the simultaneous extraction of RT, FSA and PHI were: particle size 60⁻80 mesh, temperature 30 °C, ultrasonic power 200 W, ethanol concentration 50%, solvent to material ratio 32 mL/g and extraction time 37 min. Compared to conventional extraction methods, UAE provided the highest extraction efficiency and offered many advantages including the reduction of solvent, temperature and time for extraction.