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1.
Cancers (Basel) ; 16(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38893082

RESUMO

NF2-related Schwannomatosis (NF2-SWN) is a disease that needs new solutions. The hallmark of NF2-SWN, a dominantly inherited neoplasia syndrome, is bilateral vestibular schwannomas (VSs), which progressively enlarge, leading to sensorineural hearing loss, tinnitus, facial weakness, and pain that translates to social impairment and clinical depression. Standard treatments for growing VSs include surgery and radiation therapy (RT); however, both carry the risk of further nerve damage that can result in deafness and facial palsy. The resultant suffering and debility, in combination with the paucity of therapeutic options, make the effective treatment of NF2-SWN a major unmet medical need. A better understanding of these mechanisms is essential to developing novel therapeutic targets to control tumor growth and improve patients' quality of life. Previously, we developed the first orthotopic cerebellopontine angle mouse model of VSs, which faithfully mimics tumor-induced hearing loss. In this model, we observed that mice exhibit symptoms of ataxia and vestibular dysfunction. Therefore, we further developed a panel of five tests suitable for the mouse VS model and investigated how tumor growth and treatment affect gait, coordination, and motor function. Using this panel of ataxia tests, we demonstrated that both ataxia and motor function deteriorated concomitantly with tumor progression. We further demonstrated that (i) treatment with anti-VEGF resulted in tumor size reduction, mitigated ataxia, and improved rotarod performance; (ii) treatment with crizotinib stabilized tumor growth and led to improvements in both ataxia and rotarod performance; and (iii) treatment with losartan did not impact tumor growth nor ameliorate ataxia or motor function. Our studies demonstrated that these methods, paired with hearing tests, enable a comprehensive evaluation of tumor-induced neurological deficits and facilitate the assessment of the effectiveness of novel therapeutics to improve NF2 treatments.

2.
Arab J Gastroenterol ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38755047

RESUMO

BACKGROUND AND STUDY AIMS: The integration of traditional Chinese medicine and Western medicine holds promise for the treatment of gastrointestinal disorders, which are influenced by intestinal microbiota and metabolites. This study reports a possible mechanism for the combination of Simo Decoction and Golden Bifid in functional dyspepsia (FD) by regulating intestinal microbiota and short-chain fatty acids (SCFAs). PATIENTS AND METHODS: A mouse model of food stagnation was constructed and treated with Simo Decoction combined with different concentrations of Golden Bifid. Meta-genomics sequencing was conducted to analyze the cecum contents of the mice. Following analyses of the composition and abundance of intestinal microbiota, gas chromatography-mass spectrometry was performed to measure SCFAs in the colonic content of mice. Finally, ELISA was utilized to determine the levels of pro-inflammatory factors in the duodenal mucosa of mice and the infiltration of eosinophils in the duodenum was observed by immunohistochemical staining. RESULTS: Combination of Simo Decoction and Golden Bifid more significantly alleviated dyspepsia in mice with food stagnation compared with Simo Decoction alone. The optimal ratio of combined treatment was 0.0075 mL/g (body weight) Simo Decoction and 0.0032 mg/g (body weight) Golden Bifid. The combined treatment increased the abundance of Bifidobacterium and Bacteroides in the intestine. The levels of SCFAs in the colonic contents of mice were increased after the combined treatment, contributing to diminished pro-inflammatory factors in the duodenal mucosa and reduced eosinophil infiltration. CONCLUSION: Combination of Simo Decoction and Golden Bifid increases the abundance of Bacteroides and Bifidobacterium and promotes the production of SCFAs, which is instrumental for alleviation of FD.

4.
Eur Radiol ; 33(12): 8576-8584, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37368112

RESUMO

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.


Assuntos
Imagem de Difusão por Ressonância Magnética , Rabdomiossarcoma , Animais , Camundongos , Imagem de Difusão por Ressonância Magnética/métodos , Modelos Animais de Doenças , Camundongos Nus , Imageamento por Ressonância Magnética , Rabdomiossarcoma/diagnóstico por imagem , Rabdomiossarcoma/patologia , Microvasos/diagnóstico por imagem , Microvasos/patologia , Movimento (Física)
5.
Neuro Oncol ; 25(9): 1617-1630, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-36806881

RESUMO

BACKGROUND: Neurofibromatosis 2 (NF2) is an inherited disorder caused by bi-allelic inactivation of the NF2 tumor suppressor gene. NF2-associated tumors, including schwannoma and meningioma, are resistant to chemotherapy, often recurring despite surgery and/or radiation, and have generally shown cytostatic response to signal transduction pathway inhibitors, highlighting the need for improved cytotoxic therapies. METHODS: Leveraging data from our previous high-throughput drug screening in NF2 preclinical models, we identified a class of compounds targeting the ubiquitin-proteasome pathway (UPP), and undertook studies using candidate UPP inhibitors, ixazomib/MLN9708, pevonedistat/MLN4924, and TAK-243/MLN7243. Employing human primary and immortalized meningioma (MN) cell lines, CRISPR-modified Schwann cells (SCs), and mouse Nf2-/- SCs, we performed dose response testing, flow cytometry-based Annexin V and cell cycle analyses, and RNA-sequencing to identify potential underlying mechanisms of apoptosis. In vivo efficacy was also assessed in orthotopic NF2-deficient meningioma and schwannoma tumor models. RESULTS: Testing of three UPP inhibitors demonstrated potent reduction in cell viability and induction of apoptosis for ixazomib or TAK-243, but not pevonedistat. In vitro analyses revealed that ixazomib or TAK-243 downregulates expression of c-KIT and PDGFRα, as well as the E3 ubiquitin ligase SKP2 while upregulating genes associated with endoplasmic reticulum stress-mediated activation of the unfolded protein response (UPR). In vivo treatment of mouse models revealed delayed tumor growth, suggesting a therapeutic potential. CONCLUSIONS: This study demonstrates the efficacy of proteasomal pathway inhibitors in meningioma and schwannoma preclinical models and lays the groundwork for use of these drugs as a promising novel treatment strategy for NF2 patients.


Assuntos
Neoplasias Meníngeas , Meningioma , Neurilemoma , Neurofibromatose 2 , Animais , Humanos , Camundongos , Neoplasias Meníngeas/genética , Meningioma/genética , Neurilemoma/tratamento farmacológico , Neurilemoma/genética , Neurofibromatose 2/tratamento farmacológico , Neurofibromina 2/genética
6.
bioRxiv ; 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36798353

RESUMO

Patients with Schwannomatosis (SWN) overwhelmingly present with intractable, debilitating chronic pain. There are no effective therapies to treat SWN. The drivers of pain response and tumor progression in SWN are not clear. The pain is not proportionally linked to tumor size and is not always relieved by tumor resection, suggesting that mechanisms other than mechanical nerve compression exist to cause pain. SWN research is limited by the lack of clinically-relevant models. Here, we established novel patient-derived xenograft (PDX) models, dorsal root ganglia (DRG) imaging model, and combined with single-cell resolution intravital imaging and RNASeq, we discovered: i) schwannomas on the peripheral nerve cause macrophage influx into the DRG, via secreting HMGB1 to directly stimulate DRG neurons to express CCL2, the key macrophage chemokine, ii) once recruited, macrophages cause pain response via overproduction of IL-6, iii) IL-6 blockade in a therapeutic setting significantly reduces pain but has modest efficacy on tumor growth, iv) EGF signaling is a potential driver of schwannoma growth and escape mechanism from anti-IL6 treatment, and v) combined IL-6 and EGFR blockade simultaneously controlled pain and tumor growth in SWN models. Our findings prompted the initiation of phase II clinical trial ( NCT05684692 ) for pain relief in patients with SWN.

7.
Acta Radiol ; 64(4): 1546-1555, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36259287

RESUMO

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.


Assuntos
Sarcoma , Neoplasias de Tecidos Moles , Humanos , Imagem de Difusão por Ressonância Magnética/métodos , Antígeno Ki-67 , Imagem de Tensor de Difusão/métodos , Imageamento por Ressonância Magnética/métodos , Movimento (Física) , Sarcoma/diagnóstico por imagem
8.
Acad Radiol ; 30(10): 2299-2308, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36481126

RESUMO

RATIONAL AND OBJECTIVE: To explore the correlations of histogram parameters from diffusion-weighted imaging (DWI) and intravoxel incoherent motion (IVIM) with the heterogeneous features in a nude mouse model of fibrosarcoma. MATERIALS AND METHODS: A total of 44 fibrosarcoma xenograft models were established by inoculating HT-1080 cells on the right thigh of mice and subjected tumors to DWI and IVIM imaging with 3.0 T MRI. Whole-tumor histogram parameters were calculated on apparent diffusion coefficient (ADC), pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f). Heterogeneous features, including necrosis rate, cell density, Ki-67 labeling index (LI), and microvascular density (MVD) were measured. Intraclass correlation coefficients (ICC), Pearson or Spearman correlation tests, and receiver operating characteristics (ROC) were performed. RESULTS: The 90th percentile, skewness and kurtosis of ADC and D histograms showed correlations with necrosis rate, and the highest correlation coefficient was found for D90th (r = 0.485). ADC and D histogram parameters showed correlations with cell density and Ki-67 LI; D90th showed the highest correlation coefficient with cell density (r = -0.504); and Dmedian showed the most significant correlation with Ki-67 LI (r = -0.525). D*skewness, D*kurtosis, D*90th, fmean, and fmedian showed correlations with MVD. ADC90th, ADCskewness, ADCkurtosis, D90th, and Dskewness showed significant differences between the low necrosis and high necrosis groups, and the combination model showed the best diagnostic ability (AUC = 0.882), with 97% sensitivity, and 72.7% specificity. CONCLUSION: Whole-tumor histogram parameters of DWI and IVIM were correlated with heterogeneous features in nude murine models of fibrosarcoma.


Assuntos
Imagem de Difusão por Ressonância Magnética , Fibrossarcoma , Humanos , Animais , Camundongos , Xenoenxertos , Antígeno Ki-67 , Imagem de Difusão por Ressonância Magnética/métodos , Necrose , Fibrossarcoma/diagnóstico por imagem , Movimento (Física)
9.
J Magn Reson Imaging ; 57(5): 1406-1413, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35864603

RESUMO

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.


Assuntos
Fibrossarcoma , Proteína Supressora de Tumor p53 , Humanos , Feminino , Animais , Camundongos , Antígeno Ki-67 , Estudos Prospectivos , Modelos Animais de Doenças , Reprodutibilidade dos Testes , Imageamento por Ressonância Magnética/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Proliferação de Células
10.
Food Chem ; 404(Pt B): 134308, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36323008

RESUMO

We report for the first time that curcumin is successfully encapsulated into a new natural pre-formed carrier, which was derived from arthrospore cell wall particles (APs) of probiotic Geotrichum candidum LG-8 and mainly composed of beta-1,4-glucan. Vacuum infusion process was used for efficient encapsulation of curcumin. The results showed that the encapsulation efficiency and yield of APs were 36.5 ± 0.9 % and 730.6 ± 26.5 µg/g (wet basis), respectively. Compared with the other probiotic carriers such as Saccharomyces cerevisiae, it could more effectively maintain the antioxidant property and storage capacity of curcumin under high temperature conditions. Simulated digestion was conducted to study in vitro release of curcumin encapsulated in APs, and showed a maximum bioaccessibility of 65.6 ± 3.8 %. In view of low-cost culture method, simple encapsulation process and high encapsulation capacity, G. candidum arthrospores as new natural encapsulation carriers have potential superiority in the practical application in food industry.


Assuntos
Curcumina , Parede Celular , Geotrichum , Saccharomyces cerevisiae
11.
Chem Sci ; 13(45): 13617-13622, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36507178

RESUMO

ortho-Alkynyl quinone methides are well-known four-atom synthons for direct [4 + n] cycloaddition in constructing useful oxa-heterocyclic compounds owing to their high reactivity as well as the thermodynamically favored aromatization nature of this process. Herein we report an operationally simple and eco-friendly protocol for the modular and regioselective access of (E)-4-(vinyl or aryl or alkynyl)iminochromenes from propargylamines and S-methylated ß-ketothioamides in the presence of FeCl3, and particularly under undried acetonitrile and air atmosphere conditions. This method exhibits a broad substrate scope and displays nice functional group compatibility, thus providing an efficient access of 3,4-disubstituted iminochromenes.

12.
Hemoglobin ; 46(5): 290-295, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36412578

RESUMO

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.


Assuntos
Talassemia beta , Feminino , Humanos , Talassemia beta/diagnóstico , Talassemia beta/genética , Mutação , Globinas beta/genética , Alelos , Sequenciamento de Nucleotídeos em Larga Escala
13.
Zhongguo Zhong Yao Za Zhi ; 47(11): 2964-2974, 2022 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-35718518

RESUMO

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.


Assuntos
Medicamentos de Ervas Chinesas , Quimiometria , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Raízes de Plantas/química , Controle de Qualidade
14.
NPJ Genom Med ; 7(1): 31, 2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35562572

RESUMO

Structural anomalies of the central nervous system (CNS) are one of the most common fetal anomalies found during prenatal imaging. However, the genomic architecture of prenatal imaging phenotypes has not yet been systematically studied in a large cohort. Patients diagnosed with fetal CNS anomalies were identified from medical records and images. Fetal samples were subjected to low-pass and deep whole-genome sequencing (WGS) for aneuploid, copy number variation (CNV), single-nucleotide variant (SNV, including insertions/deletions (indels)), and small CNV identification. The clinical significance of variants was interpreted based on a candidate gene list constructed from ultrasound phenotypes. In total, 162 fetuses with 11 common CNS anomalies were enrolled in this study. Primary diagnosis was achieved in 62 cases, with an overall diagnostic rate of 38.3%. Causative variants included 18 aneuploids, 17 CNVs, three small CNVs, and 24 SNVs. Among the 24 SNVs, 15 were novel mutations not reported previously. Furthermore, 29 key genes of diagnostic variants and critical genes of pathogenic CNVs were identified, including five recurrent genes: i.e., TUBA1A, KAT6B, CC2D2A, PDHA1, and NF1. Diagnostic variants were present in 34 (70.8%) out of 48 fetuses with both CNS and non-CNS malformations, and in 28 (24.6%) out of 114 fetuses with CNS anomalies only. Hypoplasia of the cerebellum (including the cerebellar vermis) and holoprosencephaly had the highest primary diagnosis yields (>70%), while only four (11.8%) out of 34 neural tube defects achieved genetic diagnosis. Compared with the control group, rare singleton loss-of-function variants (SLoFVs) were significantly accumulated in the patient cohort.

15.
PLoS One ; 17(5): e0262974, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35588435

RESUMO

Bacillus cereus is a food contaminant with widely varying enterotoxic potential due to its virulence proteins. In this article, phylogenetic analysis of the amino acid sequences from the whole-genomes of 41 strains, evolutionary distance calculation of the amino acid sequences of the virulence genes, and functional and structural predictions of the virulence proteins were performed to reveal the taxonomically diverse distribution of virulence factors. The genome evolution of the strains showed a clustering trend based on the protein-coding virulence genes. The strains of B. cereus have evolved into non-toxic risk and toxic risk clusters with medium-high- and medium-low-risk subclusters. The evolutionary transfer distances of incomplete virulence genes relative to housekeeping genes were greater than those of complete virulence genes, and the distance values of HblACD were higher than those of nheABC and CytK among the complete virulence genes. Cytoplasmic localization was impossible for all the virulence proteins, and NheB, NheC, Hbl-B, and Hbl-L1 were predicted to be extracellular. Nhe and Hbl proteins except CytK had similar spatial structures. The predicted structures of Nhe and Hbl mainly showed 'head' and 'tail' domains. The 'head' of NheA and Hbl-B, including two α-helices separated by ß-tongue strands, might play a special role in the formation of Nhe trimers and Hbl trimers, respectively. The 'cap' of CytK, which includes two 'latches' with many ß-sheets, formed a ß-barrel structure with pores, and a 'rim' balanced the structure. The evolution of B. cereus strains showed a clustering tendency based on the protein-coding virulence genes, and the complete virulence-gene operon combination had higher relative genetic stability. The beta-tongue or latch associated with ß-sheet folding might play an important role in the binding of virulence structures and pore-forming toxins in B. cereus.


Assuntos
Bacillus cereus , Fatores de Virulência , Bacillus cereus/metabolismo , Enterotoxinas/genética , Filogenia , Virulência/genética , Fatores de Virulência/metabolismo
16.
Magn Reson Med ; 88(2): 871-879, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35377480

RESUMO

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.


Assuntos
Imagem de Difusão por Ressonância Magnética , Rabdomiossarcoma , Animais , Imagem de Difusão por Ressonância Magnética/métodos , Modelos Animais de Doenças , Feminino , Imageamento por Ressonância Magnética/métodos , Camundongos , Camundongos Nus , Movimento (Física) , Rabdomiossarcoma/diagnóstico por imagem
17.
J Magn Reson Imaging ; 55(1): 225-233, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34240504

RESUMO

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.


Assuntos
Imagem de Difusão por Ressonância Magnética , Rabdomiossarcoma , Animais , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Camundongos Nus , Estudos Prospectivos , Rabdomiossarcoma/diagnóstico por imagem
18.
Acta Radiol ; 63(6): 785-793, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34000824

RESUMO

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.


Assuntos
Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Humanos , Movimento (Física) , Estudos Retrospectivos , Sensibilidade e Especificidade
19.
J Magn Reson Imaging ; 55(5): 1357-1375, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34637568

RESUMO

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.


Assuntos
Sarcoma , Neoplasias de Tecidos Moles , Inteligência Artificial , Imagem de Difusão por Ressonância Magnética/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Sarcoma/diagnóstico por imagem , Sarcoma/patologia , Neoplasias de Tecidos Moles/patologia
20.
Clin Lab ; 67(11)2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34758225

RESUMO

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.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Humanos , Imunoglobulina G , Imunoglobulina M , RNA Viral/genética , Sistema Respiratório , Sensibilidade e Especificidade
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