Power Fields (power + field)

Distribution by Scientific Domains

Kinds of Power Fields

  • high power field


  • Selected Abstracts


    Eosinophilic oesophagitis in adults

    NEUROGASTROENTEROLOGY & MOTILITY, Issue 10 2009
    N. Gonsalves
    Abstract, Previously considered a rare condition, eosinophilic oesophagitis (EoE) has become increasingly recognized as an important cause of dysphagia and food impactions in adults. This is likely attributable to a combination of an increasing incidence of EoE and a growing awareness of the condition. EoE may occur in isolation or in conjunction with eosinophilic gastroenteritis. However, the burgeoning field is likely attributable to the variant that uniquely affects the oesophagus. Adults classically present with symptoms of dysphagia, food impactions, and heartburn. Typical endoscopic features include concentric mucosal rings, linear furrowing, white plaques or exudates and a narrow caliber oesophagus. In some cases, the endoscopic features may appear normal. For years, EoE went unrecognized because eosinophilic infiltration was accepted as a manifestation of reflux, which continues to be a confounding factor in some patients. Current consensus is that the diagnosis of EoE is established by 1) the presence of symptoms, especially dysphagia and food impactions in adults, 2) ,15 eosinophils per high power field in oesophageal tissue, and 3) exclusion of other disorders with similar presentations such as GERD. Current understanding of EoE pathophysiology and natural history are limited but the entity has been increasingly linked to food allergies and aeroallergens. The main treatment options for EoE are proton pump inhibitors, dietary manipulation, and topical or oral glucocorticoids. This review highlights recent insights into EoE in adults although, clearly, much of the available data overlap with pediatrics and, occasionally, with eosinophilic gastroenteritis. [source]


    1H NMR spectroscopic method for diagnosis of malabsorption syndrome: a pilot study

    NMR IN BIOMEDICINE, Issue 2 2004
    Lakshmi Bala
    Abstract Despite its well-documented limitations, colorimetry has been commonly used for the d -xylose test in the diagnosis of malabsorption syndrome (MAS). With a possibility of overcoming its limitations, the use of 1H NMR spectroscopy for D -xylose test is explored herein. Urine samples from 35 adults with suspected MAS were obtained before and after oral ingestion of D -xylose. The diagnosis of MAS was based on fecal fat (72,h excretion using Van de Kamer's technique, normal <,7,g/24,h and/or Sudan III stain of spot stool specimen, normal,10 droplets/high power field) and/or endoscopic duodenal biopsy. Urinary excretion of D -xylose over 5,h after consumption of 5,g D -xylose, using both colorimetry and NMR was compared (normal,1,g/5,g/5,h). In vitro experiments on the standard specimens of D -xylose were also performed independently using both methods. Colorimetry showed a lower value for the quantity of D -xylose excreted in urine than NMR [median 0.73 (0.17,1.89,g) vs 1.37 (0.17,3.23,g), respectively; p<0.0001, Wilcoxon's signed ranks test]. Colorimetry and NMR correctly diagnosed 11/12 and 10/12 (p=N.S.) patients with MAS and 14/23 and 20/23 (p<0.05) without MAS, respectively. Sensitivity and specificity of colorimetry and NMR were 91.6 and 60.7% vs 83.3 and 86.9%, respectively. In in vitro experiments, the values obtained for standard xylose using NMR showed a maximum error of 7%, whereas the colorimetric method showed 20%. The NMR method is simple and may be more accurate for the D -xylose absorption test. Colorimetry was found to be inferior as compared with NMR due to its low specificity. Copyright © 2004 John Wiley & Sons, Ltd. [source]


    Criteria for extramural perineural invasion as a prognostic factor in rectal cancer

    BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 7 2001
    Dr H. Ueno
    Background: An abundant extramural autonomic nerve network is an anatomical feature of the rectum. Extramural perineural invasion (PNI) may influence the prognosis after resection of rectal cancer, however, few assessment criteria exist. Methods: PNI was investigated in 364 patients who underwent curative surgery for rectal cancer penetrating the muscular layer. A grading system was established based on the ,intensity' (number of PNI foci in a 20-power field) and ,depth' (distance from the muscularis propria) of PNI. PNI-0 was defined as without PNI, PNI-1 as ,intensity' of less than five foci and ,depth' less than 10 mm, and PNI-2 as five or more foci or 10 mm or greater ,depth' of invasion. Results: PNI was observed in 52 patients (14 per cent) and strongly correlated with pathological tumour node metastasis (pTNM) stage. Five-year survival was related to PNI grade (74 per cent in PNI-0, 50 per cent in PNI-1 and 22 per cent in PNI-2). The rate of local recurrence was also related to PNI stage: 43 per cent in PNI-2 and 9 per cent in both PNI-0 and PNI-1. Multivariate analyses showed that graded PNI was associated both with local recurrence and long-term survival, independent of tumour depth (pTNM T) and nodal involvement (pTNM N). Conclusion: The PNI grading system may be useful in prognosis and allow case selection for intensive postoperative adjuvant therapy. © 2001 British Journal of Surgery Society Ltd [source]


    An increased proportion of inflammatory cells express tumor necrosis factor alpha in idiopathic achalasia of the esophagus

    DISEASES OF THE ESOPHAGUS, Issue 5 2009
    A. Kilic
    SUMMARY Achalasia is a motility disorder characterized by the absence of coordinated peristalsis and incomplete relaxation of the lower esophageal sphincter. The etiology remains unclear although dense inflammatory infiltrates within the myenteric plexus have been described. The nature of these infiltrating cells is unknown. The aim of this study was to evaluate the expression of proinflammatory cytokines , namely, tumor necrosis factor alpha and interleukin-2 , in the distal esophageal muscle in patients with achalasia. Lower esophageal sphincter muscle from eight patients undergoing myotomy or esophagectomy for achalasia of the esophagus were obtained at the time of surgery. Control specimens consisted of similar muscle taken from eight patients undergoing operation for cancer or Barrett's esophagus. The expression of tumor necrosis factor alpha and interleukin-2 were assessed by immunohistochemistry. The total number of inflammatory cells within the myenteric plexus were counted in five high power fields. The percentage of infiltrating cells expressing tumor necrosis factor alpha or interleukin-2 was calculated. Clinical data including demographics, preoperative lower esophageal sphincter pressure, duration of symptoms, and dysphagia score (1 = no dysphagia to 5 = dysphagia to saliva) were obtained through electronic medical records. Statistical comparisons between the groups were made using the unpaired t -test, Fisher's exact test, or Mann,Whitney U test, with a two-tailed P -value less than 0.05 being considered significant. The total number of inflammatory cells was found to be similar between the groups. A significantly higher proportion of inflammatory cells expressed tumor necrosis factor alpha in achalasia as compared with controls (22 vs. 11%; P= 0.02). A similar percentage of infiltrating cells expressed interleukin-2 (40 vs. 41%; P= 0.87). Age, gender, preoperative lower esophageal sphincter pressure, or dysphagia score were not correlated to expression of these cytokines. There was, however, a significant inverse correlation between duration of symptoms and the proportion of inflammatory cells expressing tumor necrosis factor alpha in achalasia (P= 0.007). In conclusion, a higher proportion of infiltrating inflammatory cells expressed tumor necrosis factor alpha in achalasia. Furthermore, this proportion appears to be highest early in the disease process. Further studies are required to more clearly delineate the role of tumor necrosis factor alpha in the pathogenesis of this idiopathic disease. [source]


    Pathophysiologic importance of E- and L-selectin for neutrophil-induced liver injury during endotoxemia in mice

    HEPATOLOGY, Issue 5 2000
    Judy A. Lawson
    Neutrophils can cause parenchymal cell injury in the liver during ischemia-reperfusion and endotoxemia. Neutrophils relevant for the injury accumulate in sinusoids, transmigrate, and adhere to hepatocytes. To investigate the role of E- and L-selectin in this process, C3Heb/FeJ mice were treated with 700 mg/kg galactosamine and 100 ,g/kg endotoxin (Gal/ET). Immunogold labeling verified the expression of E-selectin on sinusoidal endothelial cells 4 hours after Gal/ET injection. In addition, Gal/ET caused up-regulation of Mac-1 (CD11b/CD18) and shedding of L-selectin from circulating neutrophils. Gal/ET induced hepatic neutrophil accumulation (422 ± 32 polymorphonuclear leukocytes [PMN]/50 high power fields [HPF]) and severe liver injury (plasma alanine transaminase [ALT] activities: 4,120 ± 960 U/L; necrosis: 44 ± 3%) at 7 hours. Treatment with an anti,E-selectin antibody (3 mg/kg, intravenously) at the time of Gal/ET administration did not significantly affect hepatic neutrophil accumulation and localization. However, the anti,E-selectin antibody significantly attenuated liver injury as indicated by reduced ALT levels (,84%) and 43% less necrotic hepatocytes. In contrast, animals treated with an anti,L-selectin antibody or L-selectin gene knock out mice were not protected against Gal/ET-induced liver injury. However, E-, L-, and P-selectin triple knock out mice showed significantly reduced liver injury after Gal/ET treatment as indicated by lower ALT levels (,65%) and reduced necrosis (,68%). Previous studies showed that circulating neutrophils of E-selectin,overexpressing mice are primed and activated similar to neutrophils adhering to E-selectin in vitro. Therefore, we conclude that blocking E-selectin or eliminating this gene may have protected against Gal/ET-induced liver injury in vivoby inhibiting the full activation of neutrophils during the transmigration process. [source]


    Clear cell myoepithelial carcinoma of the skin.

    JOURNAL OF CUTANEOUS PATHOLOGY, Issue 6 2009
    A case report
    Myoepitheliomas are tumors of myoepithelial cells, most frequently diagnosed in the salivary glands. Cutaneous location is very rare, especially for malignant variant. We report a case of recurrent cutaneous myoepithelial carcinoma of the femoral region in a 51-year-old woman. Histologically, the tumor was confined to the dermis and superficial subcutaneous fat tissue, exhibiting typical multinodular pattern. The majority of tumor cells were of clear cell type, although rare epithelioid and spindle cells were also present. Nuclear atypia, mitotic activity of 12 mitoses per 10 microscopic high power fields and Ki-67 labeling index of 20%, as well as three recurrences, corroborated the malignant nature of the tumor. Immunohistochemistry showed positivity for cytokeratin, epithelial membrane antigen, vimentin, S-100 protein and myogenic markers (,-smooth muscle actin and muscle-specific actin HHF-35) in keeping with the myoepithelial cell immunophenotype. Staining for CD34, desmin and HMB-45 was negative. Myoepithelial carcinoma should be considered in the differential diagnosis of cutaneous neoplasms composed predominantly of clear cells. [source]


    Malignant solitary fibrous tumor arising from the pineal region: case study and literature review

    NEUROPATHOLOGY, Issue 3 2010
    Jing Zhang
    We report a case of malignant solitary fibrous tumor involving the pineal region in a 49-year-old woman. The patient presented with headache, slowly progressive weakness of the right lower extremities and upgaze palsy over the past year. Histologically, the tumor was composed of moderately hypercellular proliferated spindle cells with eosinophilic collagen bands. These cells were diffusely and strongly immunoreactive with CD34, CD99, and vimentin, but were negative with epithelial membrane antigen, S-100 protein, Bcl-2, smooth muscle actin, cytokeratin and glial fibrillary antigenic protein. MIB-1 labeling indices and mitosis rates were 7.3 ± 1.8% and 5 per 10 high power fields, respectively. Ultrastructural examination revealed that the neoplastic cells had features of fibroblastic differentiation. Differential diagnoses included fibrous meningioma and hemangiopericytoma. The present case provides one unique example of a rare entity to the already diverse spectrum of the pineal region neoplasms encountered in neuropathology. [source]


    Leiomyosarcoma of the pulmonary vein

    PATHOLOGY INTERNATIONAL, Issue 10 2000
    Tomoko Okuno
    A case of a 74-year-old man with leiomyosarcoma of the pulmonary vein is reported. The patient felt transient chest oppression while playing golf 1 week before he visited a clinic with a common cold. He underwent an ultrasonographic examination of the heart, which showed a mass lesion in the left atrium. The preoperative clinical diagnosis was myxoma of the left atrium. Cardiac surgery revealed the mass to be a leiomyosarcoma, probably extending from the left inferior pulmonary vein. The patient underwent a left lower lobectomy of the lung, and the tumor was confirmed to have originated from the wall of the left inferior pulmonary vein. Although the patient had a metastatic lesion in the right axillary lymph node 11 months later, which was excised, he remained free of disease 14 months after the initial operation. Histologically, the tumors were composed of pleomorphic cells with bizarre nuclei and spindle cells with blunt-ended nuclei with 1,4 mitotic figures in 10 high power fields. Immunohistologically, the tumor cells were positive for , -smooth muscle actin and desmin. We reviewed 17 cases of leiomyosarcoma of the pulmonary vein (six males and 11 females with a mean age of 50 years in each group). The present case was the oldest in age and to our knowledge was the first reported case with metastasis in a distant lymph node. [source]


    Trends in incidence and survival of mesenchymal neoplasm of the digestive tract within a defined population of Northern Norway,

    APMIS, Issue 3 2006
    SONJA ERIKSSON STEIGEN
    Population-based incidence and survival data for gastrointestinal stromal tumor (GIST) are sparse due to the fact that GIST is a rather novel entity both clinically and pathologically, and has not been registered as a separate entity in population-based cancer registries. The aim of the present study was to reclassify all mesenchymal tumors within a defined population of northern Norway over a time-span of 30 years with the purpose of estimating trends of incidence and survival. One hundred and forty-one patients with mesenchymal neoplasms of the digestive tract were identified: 102 as GISTs, 32 as leiomyomatous tumors, 4 as schwannomas, and 3 as fibromas. Incidence rates of GIST showed a significant increase over the whole period, which was not observed for the non-GIST cases. Analysis of GIST cases showed that cases with more than 5 mitoses per 50 high power fields had an increased expected mortality 4 times that of those with fewer mitoses, and the combination of mitotic count and size of tumor can be recommended for categorizing the tumors into different risk levels. The study confirms that GIST is by far the most frequent mesenchymal neoplasm of the digestive tract and that the incidence has increased over the last 30 years. [source]