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91.
NMR-visible lipid signals detected in vivo by 1H MRS are associated with tumour aggression and believed to arise from cytoplasmic lipid droplets. High-resolution magic angle spinning (HRMAS) 1H MRS and Nile Red staining were performed on human brain tumour biopsy specimens to investigate how NMR-visible lipid signals relate to viable cells and levels of necrosis across different grades of glioma. Presaturation spectra were acquired from 24 adult human astrocytoma biopsy samples of grades II (8), III (2) and IV (14) using HRMAS 1H MRS and quantified using LCModel to determine lipid concentrations. Each biopsy sample was then refrozen, cryostat sectioned, and stained with Nile Red, to determine the number of lipid droplets and droplet size distribution, and with Haematoxylin and Eosin, to determine cell density and percentage necrosis. A strong correlation (R=0.92, P<0.0001) was found between the number of Nile Red-stained droplets and the approximately 1.3 ppm lipid proton concentration by 1H MRS. Droplet sizes ranged from 1 to 10 microm in diameter, and the size distribution was constant independent of tumour grade. In the non-necrotic biopsy samples, the number of lipid droplets correlated with cell density, whereas in the necrotic samples, there were greater numbers of droplets that showed a positive correlation with percentage necrosis. The correlation between 1H MRS lipid signals and number of Nile Red-stained droplets, and the presence of lipid droplets in the non-necrotic biopsy specimens provide good evidence that the in vivo NMR-visible lipid signals are cytoplasmic in origin and that formation of lipid droplets precedes necrosis. 相似文献
92.
Pediatric AIDS-Associated Lymphocytic Interstitial Pneumonia and Pulmonary Arterio-Occlusive Disease : Role of VCAM-1/VLA-4 Adhesion Pathway and Human Herpesviruses 下载免费PDF全文
Scott J. Brodie Corazon de la Rosa John Greg Howe Jill Crouch William D. Travis Kurt Diem 《The American journal of pathology》1999,154(5):1453-1464
Because the mechanisms of lymphocyte accumulation in the lungs of children with AIDS-associated lymphocytic interstitial pneumonia (LIP) are unknown, we studied the relative contributions of known adhesion pathways in mediating lymphocyte adherence to endothelium and the potential role of human herpesviruses in the expansion of these lesions. LIP was characterized by lymphoid hyperplasia of the bronchus-associated lymphoid tissue (BALT) and infiltration of the pulmonary interstitium with CD8(+) T lymphocytes. In some individuals there was expansion of the alveolar septae with dense aggregates of B lymphocytes, many containing the Epstein-Barr viral (EBV) genome. Patients with concurrent EBV infection also demonstrated large-vessel arteriopathy characterized by thickening of the intimae with collagen and smooth muscle. Venular endothelium from the lung of children with LIP, but not uninflamed lung from other children with AIDS or lung from children with nonspecific pneumonitis, expressed high levels of vascular cell adhesion molecule-1 (VCAM-1) protein. In turn, inflammatory cells expressing very late activation antigen-4 (VLA-4), the leukocyte ligand for VCAM-1, were the predominant perivascular infiltrate associated with vessels expressing VCAM-1. Expression of other endothelial adhesion molecules, including intracellular adhesion molecule-1 and E-selectin, was not uniformly associated with LIP. Using a tissue adhesion assay combined with immunohistochemistry for VCAM-1, we show that CD8(+) T cell clones that express VLA-4 bind preferentially to pulmonary vessels in sites of LIP: vessels that expressed high levels of VCAM-1. When tissues and cells were pretreated with antibodies to VCAM-1 or VLA-4, respectively, adhesion was inhibited by >/=80%. Thus, infiltration of alveolar septae with CD8(+) T cells was highly correlative with VCAM-1/VLA-4 adhesive interactions, and focal expansion of B cells was coincidental to co-infection with EBV. 相似文献
93.
Associations of B cell‐activating factor (BAFF) and anti‐BAFF autoantibodies with disease activity in multi‐ethnic Asian systemic lupus erythematosus patients in Singapore 下载免费PDF全文
H. S. Howe B. Y. H. Thong K. O. Kong H. H. Chng T. Y. Lian F. L. Chia K. S. S. Tay T. C. Lau W. G. Law E. T. Koh B. P. Leung 《Clinical and experimental immunology》2017,189(3):298-303
To measure the levels of B cell‐activating factor (BAFF) and endogenous anti‐BAFF autoantibodies in a cohort of multi‐ethnic Asian systemic lupus erythematosus (SLE) patients in Singapore, to determine their correlation with disease activity. Serum samples from 121 SLE patients and 24 age‐ and sex‐matched healthy controls were assayed for BAFF and anti‐BAFF immunoglobulin (Ig)G antibody levels by enzyme‐linked immunosorbent assay (ELISA). The lowest reliable detection limit for anti‐BAFF‐IgG antibody levels was defined as 2 standard deviations (s.d.) from blank. Correlation of serum BAFF and anti‐BAFF IgG levels with disease activity [scored by SLE Activity Measure revised (SLAM‐R)], and disease manifestations were determined in these 121 patients. SLE patients had elevated BAFF levels compared to controls; mean 820 ± 40 pg/ml and 152 pg ± 45/ml, respectively [mean ± standard error of the mean (s.e.m.), P < 0·01], which were correlated positively with anti‐dsDNA antibody levels (r = 0·253, P < 0·03), and SLAM‐R scores (r = 0·627, P < 0·01). In addition, SLE patients had significantly higher levels of anti‐BAFF IgG, which were correlated negatively with disease activity (r = –0·436, P < 0·01), levels of anti‐dsDNA antibody (r = –0·347, P < 0·02) and BAFF (r = –0·459, P < 0·01). The majority of patients in this multi‐ethnic Asian SLE cohort had elevated levels of BAFF and anti‐BAFF antibodies. Anti‐BAFF autoantibody levels correlated negatively with clinical disease activity, anti‐dsDNA and BAFF levels, suggesting that they may be disease‐modifying. Our results provide further information about the complexity of BAFF pathophysiology in different SLE disease populations and phenotypes, and suggest that studies of the influence of anti‐cytokine antibodies in different SLE populations will be required when selecting patients for trials using targeted anti‐cytokine therapies. 相似文献
94.
Xiao Bao Li Li Howe Liu Hong-Fei Shi Shu Xu Ming-Hong Wang Ju-Ying Xie 《Anatomical record (Hoboken, N.J. : 2007)》2021,304(11):2531-2537
The aim of the study was to explore the effect of acupuncture combined with rehabilitation on cognitive and motor functions in poststroke patients. All patients were divided into Group A and Group B based on different interventions (Group A: acupuncture + conventional rehabilitation, Group B: conventional rehabilitation alone). Acupuncture was conducted once a day, five times a week for 8 weeks, and rehabilitation (including physical therapy and occupational therapy) was conducted for 2 hr per session, once a day, five times a week for 8 weeks. Mini-mental State Examination (MMSE) and Fugl-Meyer Assessment (FMA) were used to assess the motor and cognitive functions at baseline and the end of 8 weeks. After the intervention, FMA and MMSE scores were improved significantly in the two groups (p <.05), compared with the scores prior to intervention. After 8 weeks of intervention, a statistically significant difference in the FMA and MMSE scores was observed between the Group A and the Group B. The results suggested that the combined intervention is more effective than the conventional rehabilitation alone in improving cognitive and motor functions in poststroke patients. 相似文献
95.
Greenberg DP Wong VK Partridge S Howe BJ Ward JI 《The Pediatric infectious disease journal》2002,21(8):769-777
OBJECTIVE: To evaluate the safety and immunogenicity of diphtheria-tetanus toxoids-acellular pertussis (DTPa)-hepatitis B (HepB) combination vaccine given at 2, 4 and 6 months of age compared with monovalent HepB vaccine given at birth, 1 month and 6 months of age and DTPa vaccine given at 2, 4 and 6 months of age. METHODS: Healthy infants were randomized to receive a combination DTPa-HepB vaccine (diphtheria and tetanus toxoids, acellular pertussis antigens and hepatitis B surface antigen), concomitantly with type b and oral poliovirus vaccines at 2, 4 and 6 months of age (Group 1) or HepB vaccine given at birth, 1 month and 6 months of age and DTPa, type b and oral poliovirus vaccines given at 2, 4 and 6 months of age (Group 2). Antibody responses were evaluated at birth, 2 months and 7 months of age. Safety was evaluated after each immunization using diary cards and parental interviews. RESULTS: One month after the third dose (7 months of age), the geometric mean concentration of antibody to hepatitis B surface antigen was approximately 3.5-fold higher in Group 2 than in Group 1 infants (3643 and 1052 mIU/ml, respectively; < 0.001). Nevertheless the rates of seroprotection to HepB (antibody to hepatitis B surface antigen > or =10 mIU/ml) in Groups 1 and 2 were similar, 99 and 100%, respectively. Also the postvaccination geometric mean concentrations and rates of seroprotection or vaccine response to all of the other vaccine antigens evaluated were similar or greater in Group 1 than in Group 2. The rates of adverse events were similar between the two groups, with fussiness and soreness at any injection site reported most frequently. CONCLUSIONS: The DTPa-HepB combination vaccine was safe and immunogenic when given to infants at 2, 4 and 6 months of age. Equivalent rates of seroprotection to hepatitis B were achieved despite a reduction of the interval between the second and third doses from 5 months in Group 2 to 2 months in Group 1. Hepatitis B-containing combination vaccines should reduce the number of vaccine injections required in childhood and maintain excellent seroprotection against multiple pathogens. 相似文献
96.
Microglandular adenosis (MGA) and atypical MGA (AMGA) are unusual lesions of the breast. They were once regarded as benign proliferative lesions and innocent bystanders. Several lines of evidence suggested that they could be neoplastic, clonal lesions and a non‐obligate precursor for triple‐negative breast cancers (TNBC). Recent work published in The Journal of Pathology by Guerini‐Rocco and colleagues provided further evidence regarding the precursor–product relationship between MGA/AMGA and TNBC. Using a massively parallel sequencing approach, they demonstrated that MGA/AMGA, particularly those associated with TNBC, could be clonal neoplastic lesions showing clonal non‐synonymous mutations, but none in pure MGA. Importantly, those alterations were observed in the associated TNBC. They were also able to identify recurrent alterations in TP53 in those MGA/AMGA cases as well as their associated TNBC. The findings, in conjunction with others, underscore the significance for MGA in clinical diagnosis. The potential of a benign lesion to progress into an aggressive malignant tumour implies that modification of the current management approach may be necessary. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
97.
Sensitive and Specific Identification of Neospora caninum Infection of Cattle Based on Detection of Serum Antibodies to Recombinant Ncp29 下载免费PDF全文
Daniel K. Howe Keliang Tang Patricia A. Conrad Karen Sverlow J. P. Dubey L. David Sibley 《Clinical and Vaccine Immunology : CVI》2002,9(3):611-615
Neosporosis is an economically important disease of dairy cattle caused by the protozoan Neospora caninum. Diagnostic tests for neosporosis are complicated by the potential for cross-reaction of antibodies to antigens that are similar between N. caninum and closely related parasites Toxoplasma gondii and Sarcocystis cruzi. To provide a sensitive and specific assay for detecting antibodies to N. caninum in the serum of infected animals, we have investigated a recombinant form of the antigen known as Ncp29 (rNcp29), which is a major surface protein of the parasite. Ncp29 is encoded by a gene that is homologous to the SAG1 gene previously characterized from T. gondii. An enzyme-linked immunosorbent assay (ELISA) was used to screen animals for the presence of serum antibodies specific to rNcp29. The rNcp29 ELISA readily distinguished between cattle known to be infected with N. caninum (optical density [OD] > 1.2 at 1:500 or greater dilution) and negative controls (OD < 0.5 at 1:500). Additionally, sera from animals that were infected with T. gondii or S. cruzi were negative. The rNcp29 ELISA developed here provides a specific and sensitive assay for detecting neosporosis in cattle. 相似文献
98.
Nye KJ Fallon D Frodsham D Gee B Graham C Howe S Messer S Turner T Warren RE 《Journal of clinical pathology》2002,55(4):286-288
AIMS: To compare the performance of four media, singly and in combination, as direct plating media for the isolation of Salmonella enterica from human faeces. METHODS: Two thousand four hundred and nine routine, faecal samples received by four laboratories were inoculated on to xylose lysine desoxycholate (XLD), desoxycholate citrate (DCA), mannitol lysine crystal violet brilliant green (MLCB), and alpha-beta chromogenic (ABC) agars using standardised protocols, reagents, and data collection. Isolates of presumptive salmonellae were identified using standard laboratory techniques and the results were analysed statistically. RESULTS: Direct plating recovered 46 of the 60 possible isolates of Salmonella spp recovered via enrichment broth. No isolates were recovered from direct plating that were not recovered via selenite enrichment. MLCB gave the highest isolation rate individually (84.8%) and amounts of competing flora (CF) did not affect the recognition of colonies. ABC proved highly specific, but insensitive, and isolation rates were adversely affected by any amount of CF. Isolation rates from XLD and DCA were only affected when the CF load was heavy. DCA was least specific, with only 9.01% of picks positive and greatest number of confirmatory tests. XLD and MLCB, in combination, gave the highest isolation rate. CONCLUSIONS: Where the earlier results of direct plating may be advantageous, XLD and MLCB provide the optimal combination. For non-typhi salmonellae, MLCB is the best, single direct plating medium. For routine diagnostic work, XLD is most effective. 相似文献
99.
Guang Yang Timothy L. Jones Thomas R. Barrick Franklyn A. Howe 《NMR in biomedicine》2014,27(9):1103-1111
The management and treatment of high‐grade glioblastoma multiforme (GBM) and solitary metastasis (MET) are very different and influence the prognosis and subsequent clinical outcomes. In the case of a solitary MET, diagnosis using conventional radiology can be equivocal. Currently, a definitive diagnosis is based on histopathological analysis on a biopsy sample. Here, we present a computerised decision support framework for discrimination between GBM and solitary MET using MRI, which includes: (i) a semi‐automatic segmentation method based on diffusion tensor imaging; (ii) two‐dimensional morphological feature extraction and selection; and (iii) a pattern recognition module for automated tumour classification. Ground truth was provided by histopathological analysis from pre‐treatment stereotactic biopsy or at surgical resection. Our two‐dimensional morphological analysis outperforms previous methods with high cross‐validation accuracy of 97.9% and area under the receiver operating characteristic curve of 0.975 using a neural networks‐based classifier. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
100.