Evaluation of factors determining the precision of body composition measurements by air displacement plethysmography

OBJECTIVES: To investigate methodological precision of air displacement plethysmography for assessment of body composition in a heterogenous sample of adults. DESIGN: Accuracy of volume measurements by air displacement plethysmography (ADP) for a range of known volumes was ascertained. Repeated measurements of body volume, lung volume, and derived body composition using the BODPOD measurement system were performed. Influence of surface area estimation on ADP measurement was investigated as a possible source of variation. SETTING: Clinical Nutrition Laboratory, School of Health & Sports Science, University of North London, London, UK. SUBJECTS: One hundred and two healthy subjects (57 women, 45 men) who ranged in age between 16 and 55 y and in BMI (kg/m(2)) between 17.8 and 41.9. STUDY DESIGN: Cross-sectional study of healthy adults for comparison with previous studies. Repeat measurements of raw body volume, lung volume and % body fat (BF) by ADP were all performed on the same day. RESULTS: From the range of known volumes a marked increase in the CV and a significantly greater measurement error were found at volumes below 40 l (P=0.04). Repeat measurements of raw body volume in human subjects resulted in a technical error equivalent to 0.8% BF. There was no significant difference found between measured and predicted lung volume and the 95% confidence interval for difference was only 0.3% BF. Repeat measurements of lung volume in our subset resulted in a technical error equivalent to 0.5% BF. Although body surface area estimation only accounted for variation in % BF of 0.1%, the extent of variation appeared to be governed by leanness (P<0.001). CONCLUSIONS: Although ADP retains excellent precision, in practice, repeat measurements of ADP should be performed whenever possible to allow for erroneous volume measurement within one procedure. Protocols for ADP measurement should be created with an awareness of those factors, which may affect measurements. SPONSORSHIPS: This study was supported by the University of North London Diversity & Development Fund.     

Combined video-assisted thoracoscopic lung volume reduction surgery and lobectomy in a high-risk patient

Nonsmall cell lung cancer often occurs in patients with severe emphysema. Lobectomy in these patients is often contraindicated due to extensive parenchymal destruction and subsequent pulmonary insufficiency. Video-assisted thoracoscopic lobectomy has been described as a less morbid procedure in high-risk patients. Lung volume reduction surgery has been shown to improve pulmonary function in selected patients with emphysema. We describe the successful combination of lobectomy and lung volume reduction surgery (LVRS) with a video-assisted thoracoscopic (VATS) approach in a high-risk patient with Stage I nonsmall cell lung cancer.     

PoleStriding exercise and vitamin E for management of peripheral vascular disease

PURPOSE: The purpose of this investigation was to evaluate the efficacy of PoleStriding exercise (a form of walking that uses muscles of the upper and lower body in a continuous movement similar to cross-country skiing) and vitamin E (alpha-tocopherol) to improve walking ability and perceived quality of life (QOL) of patients with claudication pain secondary to peripheral arterial disease (PAD). METHODS: Fifty-two subjects were randomized into four groups: PoleStriding with vitamin E (N = 13), PoleStriding with placebo (N= 14), vitamin E without exercise (N= 13), and placebo without exercise (N = 12). The dose of vitamin E was 400 IU daily. Only the PoleStriding with vitamin E and PoleStriding with placebo groups received PoleStriding instruction and training. Assignment to vitamin E or placebo was double blind. Subjects trained three times weekly for 30-45 min (rest time excluded). Individuals in vitamin E and placebo groups came to the laboratory biweekly for ankle blood-pressure measurements. RESULTS: Results of this randomized clinical trial provide strong evidence that PoleStriding significantly (P< 0.001) improved exercise tolerance on the constant work-rate and incremental treadmill tests. Ratings of perceived claudication pain were significantly less after the PoleStriding training program (P= 0.02). In contrast, vitamin E did not have a statistically significant effect on the subjects' ratings of perceived leg pain (P= 0.35) or treadmill walking duration ( P= 0.36). Perceived distance and walking speed (Walking Impairment Questionnaire) and perceived physical function (Rand Short Form-36) improved in the PoleStriding trained group only (P< 0.001, 0.022 and 0.003, respectively). CONCLUSION: PoleStriding effectively improved the exercise tolerance and perceived QOL of patients with PAD. Little additional benefit to exercise capacity was realized from vitamin E supplementation.     

Electronic off-peak status of one head of a dual-head gamma camera resulted in bone scintigraphy artifacts and faulty findings on gated myocardial SPECT

OBJECTIVE: Gamma cameras contain energy discriminators that allow only those photons within a specified energy range to be recorded. A spontaneous shift in peak of 1 head of a dual-head gamma camera may cause artifacts. We present our experience with the incidental occurrence of off-peak status in 1 head of a dual-head gamma camera that resulted in subsequent artifacts and poor-quality images. METHODS: Four patients had been scheduled to undergo imaging on a newly installed dual-head gamma camera on the same morning. The first patient underwent (201)Tl-chloride anterior and posterior total-body imaging to check for metastatic thyroid cancer, and the images were of adequate quality for interpretation. The next 2 patients underwent dual-isotope rest (201)Tl-chloride and gated dipyridamole (99m)Tc-tetrofosmin myocardial SPECT. The rest (201)Tl myocardial SPECT images of both patients showed normal perfusion in the left ventricular wall, but the dipyridamole (99m)Tc SPECT images showed virtual absence of perfusion in the apical, anterior, and lateral walls. These findings might suggest myocardial ischemia. In addition, 1 of 2 patients' cardiac gated SPECT findings led to inaccurate left ventricular ejection fractions. Technologists did not become aware of the artifacts until the fourth patient underwent total-body bone scanning, which showed faint activity with loss of contrast in the entire anterior body. One of the camera heads was then found to have off-peak status. Thus, we abandoned use of 1 detector of the dual-head gamma camera and repeated the anterior bone scanning of the 4th patient and the dipyridamole SPECT of 1 of the 2 cardiac patients. RESULTS: Gated cardiac SPECT abnormalities resulting from off-peak status were difficult to identify and included abnor-mal left ventricular wall perfusion and an inaccurate left ventricular ejection fraction. It was determined later that the off-peak status was caused by malfunction of a photomultiplier tube. CONCLUSION: Degraded planar images resulting from the off-peak status of a camera head are easily identified. The presence of the same pattern of abnormalities in 2 consecutive myocardial SPECT examinations should alert technologists to the possibility that the abnormalities are, in fact, artifacts.     

Imaging [18F]FAU [1-(2'-deoxy-2'-fluoro-beta-D-arabinofuranosyl) uracil] in dogs

We have studied the biodistribution of [(18)F]FAU [(1-(2'-deoxy-2'-fluoro-beta-D-arabinofuranosyl)uracil], which previous work has shown is incorporated into DNA and functions as an inhibitor of DNA synthesis. It is being tested as a potential antineoplastic agent and imaging agent for PET. We have produced [(18)F]FAU and injected the tracer into 3 normal dogs and imaged them for up to 4 hours and removed tissues along with blood and urine samples for HPLC and activity analysis. The results showed that [(18)F]FAU evenly distributed to most of organs. In sharp contrast to our prior experience with thymidine and its analogs, marrow had less retention of [(18)F]FAU than the non-proliferating tissues.     

Does cadaveric donor renal transplantation ever provide better outcomes than live-donor renal transplantation?

BACKGROUND: Live donor renal transplantation (LRT) now comprises more than 40% of all kidney transplants performed in the United States. Many patients on the cadaveric waiting list have a prospective live kidney donor. This study determines whether cadaveric donor renal transplantation (CRT) can demonstrate better outcomes than LRT. METHODS: From the United States Renal Data System registry, 31,909 adult recipients of a first-time kidney transplant from 1995 to 1998 were analyzed. Recipients were followed until December 31, 2000. RESULTS: CRT, more human leukocyte antigen (HLA) mismatches, increased donor age, cold ischemia time greater than 24 hr, African American recipient, and a history of diabetic nephropathy all increased the risk of graft failure, return to dialysis, and death. Nevertheless, in specific circumstances, CRT could provide better outcomes than LRT. For example, in recipients aged 18 to 59 years with a hypothetical live kidney donor aged 50 years and four HLA mismatches, the relative risk of graft loss with LRT is comparable or increased compared with CRT if the cadaveric kidney donor is much younger or with fewer HLA mismatches. On the other hand, for recipients aged 60 years or older, CRT never provides better outcomes than LRT. All analyses were adjusted for recipient race, gender, and history of diabetic nephropathy. There were no significant interactions among donor type, HLA mismatches, donor age, and cold ischemia time. CONCLUSIONS: The elderly recipient with an imminent LRT should never be offered CRT. A combination of recipient and donor factors can make CRT preferable to LRT in younger patients.     

Beneficial effect of plasmapheresis and intravenous immunoglobulin on renal allograft survival of patients with acute humoral rejection

BACKGROUND: Acute humoral rejection (AHR) has been associated with enhanced graft loss. Our study compared the renal allograft survival of patients with AHR treated with plasmapheresis (PP) and intravenous immunoglobulin (IVIG) with allograft survival in patients with acute cellular rejection (ACR). METHODS: We retrospectively analyzed all kidney transplants performed at our institution between January 1999 and August 2001 (n=286). Recipients were classified into three groups according to biopsy reports: AHR, ACR, or no rejection. The ACR group was further divided into early and late rejection (<90 and >90 days posttransplant, respectively). RESULTS: After a mean follow-up of 569+/-19 days, the incidence of AHR was 5.6% (n=16). Recipient presensitization, delayed graft function, early rejection, and higher creatinine at diagnosis were characteristic of AHR. Most AHR patients (14/16) were treated with PP and IVIG. One patient received only IVIG, whereas another received only PP. All AHR patients were given steroid pulses, but only four received antilymphocyte therapy because of concomitant severe ACR. The ACR group comprised 43 patients (15%). One patient with mild rejection received no therapy, 20 improved with steroids alone, and 22 required additional antilymphocyte therapy. One-year graft survival by Kaplan Meier analysis was 81% and 84% in the AHR and ACR groups, respectively (P=NS). Outcomes remained similar when AHR patients were compared with those with early ACR. CONCLUSIONS: We conclude that AHR, when diagnosed early and treated aggressively with PP and IVIG, carries a short-term prognosis that is similar to ACR.     

Decreased immunoreactivity for p27 protein in patients with early-stage breast carcinoma is correlated with HER-2/neu overexpression and with benefit from one course of perioperative chemotherapy in patients with negative lymph node status: results from International Breast Cancer Study Group Trial V

BACKGROUND: The objective of this study was to clarify the prognostic and predictive value of immunoreactivity for the cyclin-dependent kinase inhibitor p27(Kip1) in patients with early-stage breast carcinoma and to investigate its relation with clinicopathologic features and other markers. METHODS: Immunoreactivity for p27 protein was analyzed on tumor slides from 461 patients who were enrolled in the International Breast Cancer Study Group (IBCSG) Trial V (median follow-up, 13 years), including 198 patients with lymph node negative disease and 263 patients with lymph node positive disease. Tumors with < 50% immunoreactive neoplastic cells were considered low expressors. Immunoreactivity for p27 was correlated with several clinicopathologic characteristics. Disease free survival (DFS) and overall survival were analyzed according to p27 immunoreactivity and treatment group. RESULTS: In the lymph node negative population, decreased p27 immunoreactivity was associated with higher tumor grade (P = 0.001) and HER-2/neu overexpression (P = 0.04). In the lymph node positive population, low p27 expression was associated with higher tumor grade (P = 0.01), low expression of thymidylate synthase (P = 0.001), and higher Ki-67 expression (P = 0.007). DFS was not significantly different according to p27 status in either lymph node negative patients (10-year DFS: low p27 expression, 53% +/- 5%; high p27 expression, 55% +/- 5%) or in lymph node positive patients (10 year DFS: low p27 expression, 33% +/- 4%; high p27 expression, 32% +/- 4%). However, in the lymph node negative population, the benefit of one course of perioperative chemotherapy with cyclophosphamide, methotrexate, and 5-fluorouracil was confined exclusively to patients with tumors that showed reduced p27 immunoreactivity (P = 0.03; test for interaction). CONCLUSIONS: This analysis indicates that p27 immunoreactivity has little if any prognostic value in patients with early-stage breast carcinoma. However, these findings suggest that, in patients with breast carcinoma who have negative lymph node status, reduced p27 immunoreactivity is associated with HER-2/neu overexpression and may be predictive of a benefit from the early administration of adjuvant chemotherapy.