Use of the HEp-2 cell substrate in the detection of antinuclear antibodies in juvenile rheumatoid arthritis

Presence and titer of antinuclear antibodies (ANA) were determined in 217 juvenile rheumatoid arthritis (JRA) patients, by indirect immunofluorescence using HEp-2 cells as substrate. Positive ANA titers (greater than or equal to 1:40) were present in 131 (60%) of the JRA patients. All 3 JRA onset types demonstrated increased percentages of ANA positivity compared with healthy children. Sixty-seven percent of the patients in the polyarticular onset group had positive titers; titers were positive in 62% of the pauciarticular onset group and in 32% of the systemic onset group. ANA were also found in 45% of control patients with other connective tissue diseases. In JRA patients, the speckled pattern occurred most commonly (72%). Fourteen patients (8 with pauciarticular onset and 6 with polyarticular onset) had iridocyclitis; all of them had high titers (greater than or equal to 1:80) of ANA. The use of HEp-2 cells provided a sensitive substrate for detecting ANA in JRA. It proved to be of value in differentiating JRA patients from healthy controls, but not from patients with other connective tissue diseases.     

Increased metabolism contributes to increased resting ventilation at high altitude

Ventilatory acclimation to high altitude results in an increase in total or minute ventilation, and is associated with a fall in alveolar PCO2, i.e. alveolar hyperventilation. However, the extent to which the increase in total ventilation is matched by a greater metabolic rate (VO2, VCO2) vs alveolar hyperventilation is unclear. We sought to determine the contribution of changes in metabolic rate to the increase in minute ventilation observed during exposure to high altitude. In 12 healthy male subjects taken from Denver, Colorado (1600 m) to Pikes Peak, Colorado (4300 m) for 5 days, resting minute ventilation increased from low to high altitude (+ 26% for the 5 days) and arterialized PCO2 fell. Resting metabolic rate increased 16% for the 5 days and could account for more than half of the increase in minute ventilation. Among subjects the increases in ventilation on days 1, 2 and 4 were positively correlated with increased CO2 production; they were not correlated with arterial oxygen saturation on any day. During exercise at high altitude, PCO2 values were not different from those at rest and minute ventilation rose above low altitude values (+ 58% by day 5), but the increase could not be accounted for by an increased CO2 production. Thus at rest but not during exercise a substantial portion of the rise in minute ventilation could be attributed to increased metabolic rate.     

Patterns of morphologic alteration in residual rectal carcinoma following preoperative chemoradiation and their association with long-term outcome

Preoperative radiation (RT) and chemotherapy improve outcome in patients with locally advanced rectal adenocarcinoma and, therefore, have been used increasingly in patient management. The histopathologic alterations in postirradiated rectal adenocarcinoma and their prognostic significance have not been fully characterized. In this study, detailed analyses of morphologic alterations of stromal and tumor cells were performed in a series of 66 posttreatment rectal carcinomas, and the pathologic findings were correlated with long-term outcome. All tumors were locally advanced, with a bulky and/or tethered tumor or endorectal ultrasound or magnetic resonance imaging evidence of T3-4 and / or N1 disease. All patients were treated at one institution with preoperative RT to the pelvis (at least 4500 cGy) with or without concurrent 5-fluorouracil (5-FU)-based chemotherapy 4 to 7 weeks prior to surgical resection. Pathologic assessment showed some treatment response in all patients. Nine patients (13.4%) had complete response, and 8 (11.9%) had near-complete response (> 95% of the tumor replaced by fibroinflammatory tissue). Salient morphologic features included marked fibrosis with or without prominent inflammatory cells replacing neoplastic glands; lack of active tumor necrosis; increased mucin production and mucin pools; marked cytoplasmic eosinophilia, often in combination with marked nuclear atypia but without active mitoses in tumor cells showing treatment effect; endocrine tumor phenotype; and retention of mucosal adenoma in the presence of tumor regression within the bowel wall. With a median follow-up of 69 months, the estimated 5-year recurrence-free survival (RFS) for the entire group was 79%. By univariate analysis, the residual tumor stage (P < 0.05) and reduction of pretreatment T stage (P = 0.002) significantly correlated with RFS, as did pN stage (P = 0.002) and lymphovascular invasion (P = 0.008). The extent of treatment response did not correlate with RFS (P = 0.4). However, patients with a treatment response > or = 95% seemed to fare better than those with a treatment response < 95% (marginally significant difference in RFS, P = 0.057). Univariate and multivariate analyses identified the following morphologic patterns that were significantly associated with a reduced RFS independent of other risk factors: a fibrotic-type stromal response with minimal inflammatory infiltrates (P = 0.001) and absence of surface ulceration (P = 0.026). Our study represents the first detailed morphologic assessment of rectal carcinomas that have been subjected to long course preoperative RT and chemotherapy. Our results demonstrate distinct morphologic features in treated rectal carcinomas that are prognostically relevant.     

Laparoscopic transgastric esophageal mucosal resection for high-grade dysplasia

BACKGROUND: High-grade dysplasia of the esophageal mucosa has been shown to be a precursor to adenocarcinoma. In addition to esophagectomy, multiple ablative endoscopic techniques have evolved for the management of this condition. As a surgical alternative to esophagectomy, we describe for the first time a new option in the treatment of high-grade dysplasia. MATERIALS AND METHODS: Two patients with a history of gastroesophageal reflux disease (GERD) underwent upper gastrointestinal endoscopy which demonstrated high-grade dysplasia of the distal esophagus. The first patient had a short segment (0.5-1.0 cm), and the second patient had a longer (2 cm) segment of dysplasia. The patient is placed in the modified lithotomy position. Five trocars are placed as if to perform a fundoplication. A complete circumferential mobilization of the esophagus is performed. The short gastric vessels are divided with the harmonic scalpel, to free up the fundus of the stomach. An anterior horizontal gastrotomy is performed three to four centimeters below the gastroesophageal junction. A solution of epinephrine and normal saline (1:100,000) is injected into the mucosa at the Z-line and, utilizing specially designed hook electrocautery, the mucosa is incised circumferentially around a lighted bougie. Using blunt dissection the mucosa is undermined, elevated, and excised in four quadrants. Three centimeters of the distal esophageal mucosa are resected. The gastrotomy is then closed using a linear stapler, and a 360 degrees fundoplication is performed around a 50 Fr bougie. RESULTS: High-grade dysplasia was identified in the specimens from both patients; however, neither patient was found to have carcinoma in situ or invasive esophageal cancer. Our first patient has been followed for twenty months, the second for ten months. Both patients underwent routine upper gastrointestinal endoscopy for surveillance of the healing process. At eight months, the mucosa of the first patient showed complete regeneration of squamous epithelium. Our most recent patient appears to be progressing without complications and has also demonstrated normal squamous epithelium at ten months postoperatively, without changes of Barrett's epithelium. CONCLUSION: The technique of laparoscopic transgastric esophageal mucosal resection is feasible and may be proven to be an alternative to esophagectomy for the management of high-grade dysplasia.     

CT angiography with gadolinium-based contrast media

RATIONALE AND OBJECTIVES: To evaluate the potential use of gadolinium (Gd)-based contrast media, especially that of Gadovist, a 1-molar Gd medium, in computed tomography (CT) and compare our findings with standard iodinated contrast media. MATERIAL AND METHODS: Using a live rabbit and an acrylic CT body phantom for comparative CT imaging of Gd- and I-based media. The images were acquired at 80, 100, and 120 kVp, using fixed standard beam filtration. The phantom study used serial dilutions of the Magnevist and Ultravist 300 (2.4-molar I), whereas the animal study used different volumes of Gadovist, Magnevist (0.5 molar Gd), and Ultravist administered intravenously. RESULTS: At 80 kVp for the same injection volumes of Gadovist and Ultravist, the image contrast enhancement of the aorta with Gadovist was 40% lower than that of Ultravist. In the phantom studies, however, for the same kVp settings the CT image contrast was up to fourfold higher for Gd compared with iodine when comparing the same molar concentrations of the two elements in the solutions. CONCLUSION: These results indicate a potential of Gd-based media for clinical CT angiography and provide incentive for further investigation of this subject.     

Arthroscopic versus open shoulder stabilization for recurrent anterior instability: a prospective randomized clinical trial

BACKGROUND: Arthroscopic stabilization for anterior shoulder instability has been reported to result in a higher rate of recurrent instability compared to traditional open techniques. PURPOSE: To test the null hypothesis that there is no difference in the clinical outcomes in patients with recurrent anterior shoulder instability treated with open or arthroscopic stabilization. STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: A consecutive series of 64 patients with recurrent anterior shoulder instability were randomized to receive either arthroscopic or open stabilization by a single surgeon. Magnetic resonance arthrogram studies were obtained preoperatively. These findings were compared to arthroscopic findings. Postoperative evaluations included range of motion, stability, and subjective assessments including Single Assessment Numeric Evaluation, Simple Shoulder Test, Western Ontario Instability Index, and University of California, Los Angeles evaluation. Failure was defined as a second dislocation, recurrent subluxation, or symptoms precluding return to previous work or unrestricted active military duty. RESULTS: Sixty-one patients, 29 who received open stabilization and 32 who received arthroscopic stabilization, were evaluated at a mean of 32 months postoperatively (range, 24-48 months). Patient demographics were equivalent. Preoperative magnetic resonance arthrogram findings were confirmed at arthroscopic examination. The mean operative time was significantly shorter for the arthroscopic repairs (59 vs 149 minutes; P < .001). There were 3 clinical failures (2 open stabilizations, 1 arthroscopic stabilization) by the established criteria. There was a statistically significant improvement from preoperative to postoperative Single Assessment Numeric Evaluation scores in both groups (P < .001). The mean loss of motion (compared to the contralateral shoulder) was greater in the open shoulders. Subjective evaluations were equal in both groups. Conclusion: Clinical outcomes after arthroscopic and open stabilization were comparable. Preoperative magnetic resonance arthrograms in shoulders with anterior instability allow an accurate diagnosis of intra-articular abnormality that correlates well with operative findings. Arthroscopic stabilization for recurrent anterior shoulder instability can be performed safely; the clinical outcomes are comparable to those after traditional open stabilization.     

Dirty-appearing white matter in multiple sclerosis Preliminary observations of myelin phospholipid and axonal loss

“Dirty-appearing white matter” (DAWM) in multiple sclerosis (MS) is defined as a region(s) with ill-defined borders of intermediate signal intensity between that of normal-appearing white matter (NAWM) and that of plaque on T₂-weighted and proton density imaging. To delineate the histopathology of DAWM, four formalin-fixed cerebral hemisphere slices of three MS patients with DAWM were scanned with T₂- weighted and proton density sequences. The myelin water fraction (MWF) was obtained by expressing the short T₂ component as a fraction of the total T₂ distribution. Hemispheric sections were then stained with Luxol fast blue (LFB) for myelin phospholipids, for myelin basic protein (MBP) and 2’,3’-cyclic nucleotide 3’-phosphohydrolase (CNP) for myelin; Bielschowsky silver impregnation for axons; and for glial fibrillary acidic protein (GFAP) for astrocytes. Compared to NAWM, DAWM showed reduction in MWF, corresponding to a reduction of LFB staining. DAWM also showed reduced Bielschowsky staining. Quantitatively, the change in MWF in DAWM most consistently correlated with the change in LFB staining. The findings of this preliminary study suggest that DAWM is characterized by loss of myelin phospholipids, detected by the short T₂ component, and axonal reduction. † Deceased     

Pediatric functional magnetic resonance imaging (fMRI): issues and applications

Functional magnetic resonance imaging (fMRI) represents a useful tool for studying brain functions and the neural basis of cognition in healthy children and in those in disease states. Functional magnetic resonance imaging is a relatively new use of existing magnetic resonance imaging technology that allows scientists and practitioners to observe the brain at work. It is based on the observation that local increases in blood flow are related to neural activity. This review considers principles of functional magnetic resonance imaging, issues relevant to imaging children, and research using functional magnetic resonance imaging to examine cognitive processing in pediatric populations. The focus is specifically on language studies to review strengths, limitations, and practical applications of this technology with children. Future directions for functional magnetic resonance imaging are presented.     

Ascorbate decreases Fabry cerebral hyperperfusion suggesting a reactive oxygen species abnormality: an arterial spin tagging study

PURPOSE: To test the hypothesis that reactive oxygen species contribute to the cerebral hyperperfusion in Fabry disease. MATERIAL AND METHODS: We examined the effect of intravenous injection of ascorbate on cerebral blood flow (CBF) using magnetic resonance arterial spin tagging. Nineteen patients with Fabry disease and 15 control subjects were studied as part of a randomized double-blind placebo-controlled trial of enzyme replacement therapy (ERT). RESULTS: Vertebro-basilar hyperperfusion was observed in patients with Fabry disease. A decrease in systemic ascorbate levels relative to healthy controls was found in the patients. CBF decreased after ascorbate infusion in both control subjects and patients treated with ERT. The placebo group had a significantly delayed decrease in the CBF response after ascorbate infusion. Myeloperoxidase levels were elevated in Fabry patients, consistent with ongoing inflammatory processes in these patients. CONCLUSION: Increased CBF in Fabry disease may be related to increased production of reactive oxygen species, while low plasma ascorbate levels suggests a global redox imbalance. These abnormalities were improved by ERT. These observations have implications regarding oxidative processes contributing to accelerated atherosclerosis in Fabry disease.