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11.
Elizabeth M Genega Malathy Kapali Marta Torres-Quinones William C Huang Jill S Knauss Li-Ping Wang Puthiyaveettil N Raghunath Christopher Kozlowski Stanley Bruce Malkowicz John E Tomaszewski 《Modern pathology》2005,18(1):11-18
The classification of urothelial neoplasms of the kidney traditionally has been similar to that of urinary bladder tumors. Several years ago, the classification of papillary urothelial neoplasms was revised. The current study focuses on the application of the 1998 World Health Organization (WHO)/International Society of Urological Pathology classification system to 102 renal pelvic urothelial neoplasms and compares it to the 1973 WHO classification scheme. In this study, all tumors were classified as urothelial carcinomas, and the majority (85%) were papillary. Most patients with papillary tumors presented with 'superficial' disease (< or = pT1). With the 1998 system, most papillary carcinomas were high grade, and were more often invasive as compared to low-grade tumors. Only 34% were low-grade papillary tumors and, of these, most (93%) were noninvasive. With the 1973 system, most papillary tumors were grade 2 or 3, with invasion more common in grade 3 tumors. By 1973 criteria, grade 2 tumors were a heterogeneous group; with 1998 criteria, nearly one-half were high grade and the other half low grade. The grade of papillary urothelial carcinomas with both the 1973 and 1998 grading methods was associated with stage (P=0.001). Our study reveals that papillomas and papillary urothelial neoplasms of low malignant potential are uncommon tumors in the kidney. Renal pelvic papillary urothelial neoplasms are most often carcinomas and are more commonly high grade than low grade. Although both the 1973 and 1998 systems showed a significant association with tumor stage, grade 2 papillary carcinomas are a heterogeneous group by 1973 criteria. The 1998 system provides useful information in that it more clearly defines a papillary tumor's grade and selects for a group of tumors, namely low-grade papillary urothelial carcinomas, for which a low likelihood of invasion can be predicted. 相似文献
12.
13.
Gamma-carboxylated isoforms of recombinant human protein S with different biologic properties 总被引:3,自引:0,他引:3
Grinnell BW; Walls JD; Marks C; Glasebrook AL; Berg DT; Yan SB; Bang NU 《Blood》1990,76(12):2546-2554
Human protein S (HPS), a regulator of hemostasis, is a vitamin K- dependent plasma protein with potential clinical utility. We have obtained high-level expression of the cDNA for HPS in two mammalian cell lines. Both cell lines secreted single chain recombinant HPS (rHPS) in serum-free medium as determined by Western blot analysis. The ability of the rHPS from both cell lines to act as a cofactor for human protein C (HPC) was determined; the rHPS secreted from the human 293 cell line had an activity six times that of the rHPS from the AV12-664 Syrian hamster cell line. Furthermore, the relative specific cofactor activity of rHPS from the 293 cell line was actually 2.5-fold higher than that of single-chain human plasma-derived HPS. Essentially all of the rHPS secreted from the 293 cell line exhibited a calcium-dependent elution profile on anion exchange chromatography, whereas only 25% to 35% of the hamster cell-derived rHPS exhibited this profile. However, the calcium-eluted rHPS from the AV12 cell line had a high specific cofactor activity, equivalent to that of the 293-derived rHPS. A NaCl- elutable rHPS fraction (calcium nondependent) was isolated from the recombinant AV12-664 cell line, further purified, and found to have reduced activity, only 40% that of the calcium-dependent rHPS. The only observable difference in the calcium-dependent and nondependent rHPS molecules was in the content of gamma-carboxyglutamic acid (Gla); the calcium-dependent material contained approximately 10 mol Gla/mol protein whereas the calcium-nondependent material contained only approximately 8 mol Gla/mol of protein. In addition, the calcium- nondependent rHPS had reduced ability to interact with phospholipid vesicles as evidenced by an eightfold increase in the apparent kd. Our data demonstrate the isolation of rHPS with high specific activity, and show that a reduction in as few as two Gla residues dramatically decreases its functional cofactor activity for HPC, due to a reduction in ability to interact with the phospholipid bilayer. 相似文献
14.
Introduction. Until recently, patients with brain injuries had poor prognosis for recovery, but new insights into neuroplasticity and neurorehabilitation have significantly improved outcomes. Neurotherapy or neurofeedback is one of those promising techniques for neurorehabilitation. Methods. Neurofeedback or EEG biofeedback, as it is also called, uses operant conditioning to reinforce desirable self-regulated changes in EEG rhythms, changes that are believed to correspond to reorganization in neural networks, particularly in thalamocortical and corticothalamic circuits. Sensorimotor rhythm reinforcement has been effective in facilitating recovery in patients with traumatic brain injury, stroke, seizures, and certain sleep disorders. Results. We describe the case of a 19-year-old man with severe, partial secondarily generalized seizures that did not respond to extensive conventional treatments including all antiepilepsy drugs. Conclusion. He underwent two 3-week sessions of daily neurotherapy, which produced remarkable EEG and behavioral normalization. 相似文献
15.
Acquired immune hemolytic anemia associated with IgA erythrocyte coating: investigation of hemolytic mechanisms 总被引:1,自引:0,他引:1
We have investigated the hemolytic mechanisms in a patient with acquired immune hemolytic anemia whose red cells appeared to be coated with IgA alone. The clinical course was similar to that of patients with hemolytic anemia mediated by warm-reacting IgG antibody. Splenic sequestration of red cells was demonstrated, and marked reduction of hemolysis occurred after corticosteroid therapy. Antibody was eluted from the patient's red cells and used to sensitize normal red cells in vitro. These sensitized red cells were not lysed by fresh autologous serum, nor did they fix detectable amounts of C3. However, red cells sensitized by eluted antibody were lysed by normal human peripheral blood monocytes in a system designed to demonstrate antibody-dependent cell-mediated cytotoxicity. Monocyte-mediated hemolysis of sensitized red cells was inhibited by the addition of low concentrations of normal serum IgA to the system, but not by IgG. The ability of the eluate to induce monocyte-mediated hemolysis was abolished by its adsorption on Sepharose-bound anti-IgA, but not by preincubation with Sepharose-bound anti-IgG. In addition, normal human monocytes were demonstrated to ingest eluate-sensitized red cells. These data demonstrate an in vitro interaction of IgA-sensitized red cells with leukocytes and suggest a possible mechanism for the patient's hemolysis. 相似文献
16.
Pancreas divisum: thin-section CT 总被引:1,自引:0,他引:1
Zeman RK; McVay LV; Silverman PM; Cattau EL; Benjamin SB; Fleischer DF; Garra BS; Jaffe MH 《Radiology》1988,169(2):395-398
Twelve patients with known pancreas divisum underwent thin-section computed tomography (CT) to determine the capability of CT to depict this pancreatic anomaly. Focal pancreatic enlargement was present in five patients. Two distinct pancreatic moieties separated by a fat cleft were noted in three patients; a fourth patient had focal atrophy in the distribution of the dorsal pancreas. The two pancreatic moieties were identified at the same craniocaudal level in all four of these patients. The dorsal duct was depicted in all 12 patients, while the short ventral duct was seen in only five of the 12 patients. Failure of the ventral and dorsal pancreatic ducts to fuse was identified in all five patients in whom both ducts were seen. CT may not enable specific diagnosis of pancreas divisum in the majority of patients. If, however, distinct pancreatic moieties or unfused ductal systems are evident, the diagnosis may be confidently suggested. 相似文献
17.
Nabil Elkassabany Moustafa Ahmed S. Bruce Malkowicz Daniel F. Heitjan Joshua A. Isserman E. Andrew Ochroch 《Journal of clinical anesthesia》2013,25(6):459-465
Study ObjectiveTo compare the efficacy of ultrasound-guided tansversus abdominis plane (TAP) block with placebo for postoperative analgesia after retropubic radical prostatectomy (RRP).DesignProspective, randomized, double-blinded study.SettingTertiary-care Veterans Affairs (VA) hospital.PatientsASA physical status 1, 2, and 3 patients scheduled for RRP.InterventionsPatients were randomized to two groups: the TAP group and the control group. All patients underwent an ultrasound-guided TAP block procedure after induction of general anesthesia and received either local anesthetic (TAP group) or normal saline (control group).MeasurementsOpioid use and verbal analog pain scores at 1, 6, 12, and 24 hours after surgery were recorded, as was the frequency of side effects. Times to ambulation and first oral intake also were recorded.Main ResultsThe TAP block group had lower pain scores and required less total opioid in the first 24 hours after surgery. Time to first oral intake and time to ambulation were similar between the two groups.ConclusionThe TAP block has early benefits in postoperative analgesia after RRP. 相似文献
18.
Matthew J. Resnick Meredith Bergey Laurie Magerfleisch John E. Tomaszewski S. Bruce Malkowicz Thomas J. Guzzo 《BJU international》2011,107(1):46-52
THIS IS A COMMENT MODERATED PAPERavailable at http://www.bjui.org/commentary Study Type – Therapy (case series)Level of Evidence 4 What’s known on the subject? and What does the study add? Lymphovascular invasion (LVI) is a prognostic marker for biologically aggressive disease in numerous tumour types. Indeed, numerous studies have documented the negative prognostic value of LVI in bladder cancer patients who have undergone radical cystectomy, however few studies have evaluated the prognostic value of LVI at TURBT. The current study examines both the concordance between the presence of LVI at TURBT and radical cystectomy specimens and furthermore examines the survival implications of the presence of LVI at both TURBT and radical cystectomy.
OBJECTIVE
To evaluate the concordance transurethral resection of bladder tumour (TURBT) and radical cystectomy (RC) specimens with regard to the presence of lymphovascular invasion (LVI). Additionally, to evaluate the prognostic value of LVI in the prediction of lymph node metastases, overall survival, disease‐specific survival and recurrence‐free survival following RC.PATIENTS AND METHODS
The records of 487 patients who underwent RC at our institution between 1987 and 2008 were retrospectively reviewed and evaluated for the presence or absence of LVI as determined by pathological evaluation. The presence or absence of LVI was then evaluated on previous transrectal resection specimens of this cohort of patients undergoing RC. Cox regression and Kaplan–Meier analysis were undertaken to evaluate the contribution of LVI to various outcomes.RESULTS
Of 474 patients with complete LVI data, 60 (12.3%) were found to have LVI at TURBT compared to 161 (33.1%) at RC. Although the presence of LVI at TURBT was more significantly associated with the presence of LVI at RC, only 42.9% of patients in whom LVI was documented at TURBT were found to harbour LVI at RC. The risk of nodal disease was higher in those patients with LVI at TURBT than in those with no evidence of LVI at TURBT (48.3% vs 25.0%, P < 0.001). Additionally, LVI at TURBT was associated with an increasing risk of pathological upstaging and the receipt of adjuvant chemotherapy. Survival analysis showed a significant decrement in overall and recurrence‐free survival among those with LVI at TURBT compared to those with no evidence of LVI.CONCLUSIONS
Lymphovascular invasion at TURBT provides useful prognostic information that should be incorporated into clinical decision‐making, particularly with regard to cystectomy for nonmuscle‐invasive carcinoma and the administration of neoadjuvant chemotherapy. 相似文献19.
Alvin C Ng Meng Ai Png P Chandra Mohan Joyce SB Koh Tet Sen Howe 《Journal of bone and mineral research》2014,29(3):639-643
In 2010, the American Society for Bone and Mineral Research (ASBMR) task force defined major and minor features to assist in the case finding and reporting of atypical femoral fractures (AFFs). One major feature that was proposed was a “transverse or short oblique configuration.” Our primary aim was to compare the conventional overall fracture morphology (OFM) with its associated angle (OFMA) and our proposed lateral cortical fracture angle (LCFA) in the assessment of fracture configuration in suspected AFFs and non‐AFFs. The radiographs of 79 patients with AFFs and 39 patients with non‐AFFs were each analyzed by two blinded reviewers to obtain the OFM, OFMA, and LCFA. Using the overall fracture morphology to assess the suspected AFFs resulted in discordance between reviewers in 18 cases (22.8%), of which 5 (6.3%) were discordant between short oblique (>30° to 60°) and long oblique (>60° to 90°) configurations, therefore affecting their classifications as AFFs. By assessing only the critical component within the lateral cortex, all the suspected AFFs fell well within the classification as transverse fractures with a mean LCFA of 4.8° (range 0.3 to 18.0, SD = 4.23). The inter‐reader variability was also lower for LCFA versus OFMA (4.1° versus 6.9°, p = 0.001) when used to assess AFFs. Fracture angles were significantly different in AFFs versus non‐AFFs regardless of whether the OFMA or LCFA methodology was employed, but the greater difference associated with LCFA suggests its greater discriminating power. When LCFA was used in conjunction with 0° to 30° as the criteria for transverse morphology, all the AFFs and non‐AFFs were correctly classified. By using a standardized and precise method in measuring the fracture angle, specifically using only the component of the lateral cortex and limiting to truly transverse fractures, ie, between 0° and 30°, the LCFA is a robust and accurate method to assess the fracture morphology in suspected AFFs. © 2014 American Society for Bone and Mineral Research. 相似文献
20.
Eugene J. Pietzak MD Wei-Ting Hwang PhD S. Bruce Malkowicz MD Thomas J. Guzzo MD MPH 《Annals of surgical oncology》2014,21(13):4383-4389