Fruit and vegetable consumption, pesticide residue intake from consumption of fruits and vegetables, and risk of uterine fibroids

OBJECTIVE

To examine the association between consumption of fruits and vegetables and pesticide residue intake from consumption of fruits and vegetables and risk of ultrasound- or hysterectomy-confirmed fibroids. Only a few studies have evaluated the association of fruit and vegetable intake with uterine fibroids, with inconsistent results. No studies have examined pesticide exposure through fruits and vegetables with fibroid risk.

DESIGN

Prospective cohort study. Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).

SETTING

Not applicable.

PATIENT(S)

A total of 81,782 premenopausal participants from the Nurses' Health Study II cohort were followed from 1991 to 2009 for fruit and vegetable analysis, and 49,927 participants were followed from 1999 to 2009 for pesticide residue burden analysis. Their diet was assessed every 4 years with a food frequency questionnaire. Fruits and vegetables were classified into high- or low-pesticide residues using a validated method based on surveillance data from the US Department of Agriculture.

INTERVENTION(S)

Not applicable.

MAIN OUTCOME MEASURE(S)

Cases of ultrasound- or hysterectomy-confirmed fibroids were identified from self-reports to validated questionnaires.

RESULT(S)

From 1991 to 2009, 9,706 incident cases of ultrasound- or hysterectomy-confirmed fibroids were reported, and 4,195 incident cases were identified from 1999 to 2009. No association was observed between total fruit and vegetable consumption and uterine fibroid risk. Participants with the highest intake of total fruits (≥4/day) were 10% less likely to develop uterine fibroids compared with participants who consumed <1/day (95% CI = 0.80-1.01). No associations were observed with any other fruit or vegetable groups. An inverse association was observed between intake of high-pesticide-residue fruits and vegetables and fibroid risk (HR for 5th vs. 1st quintile = 0.87; 95% CI = 0.77-0.99), while no association with low-pesticide-residue fruits and vegetables was observed (HR for 5th vs. 1st quintile = 1.08; 95% CI = 0.95-1.23).

CONCLUSION(S)

Our findings suggest that pesticide residues on fruits and vegetables are not associated with a higher risk of uterine fibroids. Furthermore, our results suggest that intake of fruits may be associated with a lower risk of fibroids. Future research in this area should focus on dietary exposures across the life course as well as assessment of class-specific pesticides.

Genital Powder Use and Risk of Epithelial Ovarian Cancer in the Ovarian Cancer in Women of African Ancestry Consortium

BACKGROUND

Genital powder use is more common among African-American women; however, studies of genital powder use and ovarian cancer risk have been conducted predominantly in White populations, and histotype-specific analyses among African-American populations are limited.

METHODS

We used data from five studies in the Ovarian Cancer in Women of African Ancestry consortium. Participants included 620 African-American cases, 1,146 African-American controls, 2,800 White cases, and 6,735 White controls who answered questions on genital powder use prior to 2014. The association between genital powder use and ovarian cancer risk by race was estimated using logistic regression.

RESULTS

The prevalence of ever genital powder use for cases was 35.8% among African-American women and 29.5% among White women. Ever use of genital powder was associated with higher odds of ovarian cancer among African-American women [OR = 1.22; 95% confidence interval (CI) = 0.97-1.53] and White women (OR = 1.36; 95% CI = 1.19-1.57). In African-American women, the positive association with risk was more pronounced among high-grade serous tumors (OR = 1.31; 95% CI = 1.01-1.71) than with all other histotypes (OR = 1.05; 95% CI = 0.75-1.47). In White women, a significant association was observed irrespective of histotype (OR = 1.33; 95% CI = 1.12-1.56 and OR = 1.38; 95% CI = 1.15-1.66, respectively).

CONCLUSIONS

While genital powder use was more prevalent among African-American women, the associations between genital powder use and ovarian cancer risk were similar across race and did not materially vary by histotype.

IMPACT

This is one of the largest studies to date to compare the associations between genital powder use and ovarian cancer risk, overall and by histotype, between African-American and White women.

Abstract PO-180: Genital powder use and risk of epithelial ovarian cancer in the Ovarian Cancer in Women of African Ancestry Consortium

PURPOSE: To date, the epidemiology of epithelial ovarian cancer (EOC) among African-American women has been severely understudied. It remains unclear to what extent variation in the prevalence of EOC risk factors may explain incidence disparities between African-American and white women. Genital powder use is more common among African-American women; however, studies of genital power use and EOC risk have been conducted predominantly in white populations, and histotype specific analyses among African-American populations are limited. The objective of this study was to evaluate the association between genital powder use and EOC risk among African-American and white women, overall and by histotype.

METHODS: We used data from four ovarian cancer case-control studies in the Ovarian Cancer in Women of African Ancestry (OCWAA) consortium: the African American Cancer Epidemiology Study, the Los Angeles County Ovarian Cancer Study, the Cook County Case-Control Study, and the North Carolina Ovarian Cancer Study. Participants included 601 African-American cases, 1,012 African-American controls, 2,225 white cases, and 3,086 white controls who answered questions on genital powder use prior to 2014. The association between genital powder use and EOC risk was estimated using logistic regression. Pooled histotype specific odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated using polytomous logistic regression. The population attributable risk (PAR) by race was calculated using the Bruzzi method. RESULTS: The prevalence of reporting ever genital powder use was 66% among African-American women and 44% among white women. African- American women who ever used genital powder were 29% more likely to develop EOC compared to African-American women who reported no use (OR=1.29, 95% CI=0.98-1.71). White women who ever used genital powder were 36% more likely to develop EOC compared to white women reporting no use (OR=1.36, 95% CI=1.12- 1.52). The associations were similar when examined by histotype. Among African- American women, the ORs were 1.29 (95% CI=0.94-1.76) for high grade serous (HGS) and 1.38 (95% CI=0.87-2.19) for non-HGS. For white women, the corresponding ORs were 1.27 (95% CI=1.06-1.52) and 1.21 (95% CI=0.96-1.56), respectively. The PAR for genital powder use was slightly higher, but not statistically significantly different, in African-American women (PAR=10.7, 95% CI=3.7-17.5) compared to white women (PAR=7.8, 95% CI=4.9-10.7). CONCLUSION: While the prevalence of ever genital body powder use was higher among African-American women, the associations between genital powder use and ovarian cancer risk were similar between African-American and white women, and did not materially vary by histotype. Further analyses incorporating additional OCWAA studies and using more refined exposure categories (e.g., frequency and duration of powder use, age at first application) are currently being conducted.

Citation Format: Colette P. Davis, Elisa V. Bandera, Traci N. Bethea, Tareq F. Camacho, Charlotte E. Joslin, Anna H. Wu, Alicia Beeghly-Fadiel, Emily K. Cloyd, Patricia G. Moorman, Evan Myers, Heather M. Ochs-Balcom, Lauren C. Peres, Will L. Rosenow, Veronica W. Setiawan, Lynn Rosenberg, Joellen M Schildkraut, Holly R. Harris. Genital powder use and risk of epithelial ovarian cancer in the Ovarian Cancer in Women of African Ancestry Consortium [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-180.

A randomized, placebo-controlled study to evaluate the role of salmeterol in the in-hospital management of asthma

STUDY OBJECTIVES

To assess the safety and efficacy of salmeterol xinafoate as an adjunct to conventional therapy for the in-hospital management of acute asthma.

DESIGN

A prospective, double-blind, randomized placebo-controlled trial.

SETTING

Medical wards of a large university-based hospital.

PATIENTS

Forty-three patients admitted for an acute exacerbation of asthma.

INTERVENTIONS

Salmeterol (42 microg) or two puffs of placebo every 12 h in addition to standard therapy (short-acting beta-agonists, corticosteroids, and anticholinergic agents).

RESULTS

No clinically adverse effects were seen with the addition of salmeterol to conventional therapy. After salmeterol, there was no difference in pulse, respiratory rate, oxygen saturation by pulse oximetry, severity of symptoms, or dyspnea score. Patients receiving salmeterol had greater FEV(1) percent improvements than the placebo group at 12, 24, 36, and 48 h. These findings were not statistically significant. By paired Student's t tests, there were significant improvements in FEV(1) (p = 0.03) and FVC (p = 0.03) in the salmeterol group after 48 h of treatment with no comparable improvement in the placebo group. In a subgroup analysis of patients with an initial FEV(1) < or = 1.5 L, the absolute FEV(1) percent improvement for salmeterol vs placebo was 51% vs 16% at 24 h and 54% vs 40% at 48 h. The relative FEV(1) percent improvement for salmeterol vs placebo was 17% vs 8% at 24 h and 18% vs 14% at 48 h.

CONCLUSION

The addition of salmeterol to conventional therapy is safe and may benefit hospitalized patients with asthma. Further studies are needed to clarify its role in the treatment of acute exacerbation of asthma.

Point mutations identify a conserved region of the saccharomyces cerevisiae AFR1 gene that is essential for both the pheromone signaling and morphogenesis functions

Mating pheromone receptors activate a G protein signal pathway that leads to the conjugation of the yeast Saccharomyces cerevisiae. This pathway also induces the production of Afr1p, a protein that negatively regulates pheromone receptor signaling and is required to form pointed projections of new growth that become the site of cell fusion during mating. Afr1p lacks strong similarity to any well-characterized proteins to help predict how it acts. Therefore, we investigated the relationship between the different functions of Afr1p by isolating and characterizing seven mutants that were defective in regulating pheromone signaling. The AFR1 mutants were also defective when expressed as fusions to STE2, the alpha-factor receptor, indicating that the mutant Afr1 proteins are defective in function and not in co-localizing with receptors. The mutant genes contained four distinct point mutations that all occurred between codons 254 and 263, identifying a region that is critical for AFR1 function. Consistent with this, we found that the corresponding region is very highly conserved in the Afr1p homologs from the yeasts S. uvarum and S. douglasii. In contrast, there were no detectable effects on pheromone signaling caused by deletion or overexpression of YER158c, an open reading frame with overall sequence similarity to Afr1p that lacks this essential region. Interestingly, all of the AFR1 mutants showed a defect in their ability to form mating projections that was proportional to their defect in regulating pheromone signaling. This suggests that both functions may be due to the same action of Afr1p. Thus, these studies identify a specific region of Afr1p that is critical for its function in both signaling and morphogenesis.

Inflammatory mediators induce sequestration of VE-cadherin in cultured human endothelial cells

The mechanisms through which inflammatory mediators modify endothelial junctional structure are not well understood. Endothelial cells exposed to 1 mM H2O2, 0.1 mM histamine or 4 mM EDTA displayed decreased amounts of VE-cadherin on the cell surface in a time-dependent manner. H2O2 and EDTA-treated cells showed a sustained reduction in surface VE-cadherin, but histamine (0.1 mM) decreased cell surface VE-cadherin only at 5 and 15 min, not at 30 and 60 min. Sequestering of VE-cadherin could also be visualized as a decrease in immunofluorescent labeling of endothelial junctions in fixed, non-extracted monolayers. However, junctional staining was observed in these cells after membrane extraction. This decreased surface expression of VE-cadherin was actin-filament, but not PKC/MAP kinase dependent. VE-cadherin binding to the cytoskeleton was decreased by EDTA, but was not diminished by histamine or H2O2. Therefore, by promoting sequestration of junctional cadherins, inflammatory mediators may decrease adhesive bonds between apposed endothelial cells and increase solute permeability.

Successful treatment of valproic acid overdose with hemodialysis

A 43-year-old woman took a large amount of depakote (divalproex, a slow-release form of valproate), became comatose, and developed severe hypotension refractory to fluid resuscitation and high-dose vasopressors. The serum valproic acid (VPA) concentration on admission was 1,380 microgram/mL (therapeutic range, 50 to 100 microgram/mL). She also had metabolic acidosis, thrombocytopenia, and normal renal and liver functions. Hemodialysis was initiated 4 hours after presentation. After 6 hours of hemodialysis with a high-flux dialyzer, her serum VPA concentration decreased from 940 microgram/mL to 164 microgram/mL, coincident with improvement in clinical status. The half-life of VPA was reduced to 2.4 hours with hemodialysis, whereas it was 7.2 hours before the procedure. Hemodialysis could be a valuable therapeutic intervention in VPA toxicity.

Phytophotodermatitis: the other "lime" disease

Phytophotodermatitis is a skin eruption that occurs after contact with photosensitizing compounds in plants and exposure to UV light. There are two common presentations of phytophotodermatitis. Acutely, erythema and vesiculation similar to a severe sunburn are noted. After resolution of the inflammation, the involved skin has marked hyperpigmentation. Many plants have been identified that contain furocoumarins (psoralens), including limes, lemons, and celery. We present a patient with an acute phototoxic eruption and hyperpigmentation after contact with limes during a beach vacation.

Expression of zonula occludens and adherens junctional proteins in human venous and arterial endothelial cells: role of occludin in endothelial solute barriers

OBJECTIVE

The purpose of this study was to correlate the expression of occludin and VE-cadherin with the solute barrier properties of arterial and venous endothelial monolayers.

METHODS

Immunofluorescent confocal and traditional microscopy were used to determine junctional protein localization in endothelium in vivo and in vitro respectively, and western and northern analysis used to determine protein and gene expression levels. Permeability of endothelial monolayers was examined under normal, low calcium, and cytochalasin-D treatment conditions. Antisense oligonucleotide experiments for occludin were performed to determine the contribution of occludin to solute barrier.

RESULTS

Occludin protein in endothelial monolayers is more concentrated in arterial junctions than in venous junctions both in vivo and in vitro. Arterial endothelial cells express 18-fold more occludin protein and nine times more occludin mRNA compared to venous endothelial cells. In vivo, both endothelial cells demonstrate VE-cadherin staining; and in vitro, only venous endothelial cells express VE-cadherin protein and mRNA. Occludin antisense experiments suggest that both arterial and venous barrier properties are due to these different amounts of occludin expression. Venous barrier was remarkably sensitive to low extracellular calcium, while arterial barrier was more sensitive to cytochalasin-D.

CONCLUSIONS

These findings suggest strongly that arterial and venous endothelial barrier reflects the level of expression of different adhesion molecules and that modulation of these proteins, especially occludin, may regulate the level of endothelial solute barrier.

Diagnostic impact of four postprocessing techniques in evaluating contrast-enhanced three-dimensional MR angiography

OBJECTIVE

The purpose of this study was to determine the added diagnostic value of various three-dimensional (3D) data viewing techniques when analyzing contrast-enhanced 3D MR angiography.

MATERIALS AND METHODS

Twenty patients (mean age, 62 years) with symptomatic peripheral vascular disease were assessed with breath-hold, contrast-enhanced 3D MR angiography and catheter angiography, which served as the standard of reference. After an initial interpretation of the 3D MR angiographic data sets based only on standardized maximum intensity projections (MIP), the diagnostic gain of the stepwise addition of interactive multiplanar reformations, shaded-surface displays (SSD), and virtual intraarterial endoscopy (VIE) images was calculated. Time required for each step of postprocessing was measured.

RESULTS

Pathologic changes were revealed by catheter angiography in 60 vascular segments (50 severe stenoses, seven aneurysms, and three occlusions). The average postprocessing times were MIP, 8 min (range, 5-12 min); multiplanar reformations, 9 min (range, 3-11 min); SSD, 15 min (range, 8-25 min); and VIE, 40 min (range, 18-63 min). Addition of multiplanar reformations to MIPs resulted in the greatest gain of diagnostic accuracy, from 92% to 96%, and diagnostic confidence. When analysis was based on all four techniques, receiver operating characteristic curve analysis revealed only minimal improvements in diagnostic confidence, whereas diagnostic accuracy remained unchanged at 96%.

CONCLUSION

Accurate and time-effective analysis of contrast-enhanced 3D MR angiography should be based on MIP algorithms and multiplanar reformations. Additional evaluation with VIE or SSD techniques is time-consuming and provides little diagnostic gain.

Postprocessing techniques for gadolinium-enhanced three-dimensional MR angiography

Contrast material-enhanced three-dimensional (3D) magnetic resonance (MR) angiography is rapidly gaining acceptance as a versatile noninvasive alternative to conventional angiography. The technique has proved useful in the visualization and assessment of complex pathologic entities in the thoracic and abdominal aorta, renal arteries, pelvic arterial system, and pulmonary arteries. Several postprocessing techniques are available for reformation of the imaging data, including maximum intensity projection (MIP), surface rendering, and virtual intraluminal endoscopy (VIE). MIP and subvolume MIP reconstructions can be produced quickly and are useful for demonstration and archiving purposes. Because of its unique ability to display vessels without overlap, surface rendering is especially useful in depicting diseases that influence either the outer shape of the vessels or their topographic arrangement. VIE allows assessment of the inside of the vascular wall and is helpful in detecting wall-bound thrombus and evaluating the degree of stenosis. Most clinically relevant questions (eg, presence of pulmonary embolism, aortic aneurysm, renal artery stenosis) can be fully answered if analysis is based on MIP and thin multiplanar reformations of contrast-enhanced 3D MR angiograms. In some cases, the use of additional postprocessing techniques enhances diagnostic confidence.

New approach to patency and flow assessment after left internal thoracic artery hypoperfusion syndrome with additional saphenous vein graft to the left anterior descending artery with phase-contrast magnetic resonance angiography

OBJECTIVE

Perioperative and early postoperative flow reduction of a left internal thoracic artery conduit is a rare complication of myocardial revascularization and may lead to the potentially fatal left internal thoracic artery hypoperfusion syndrome. It has been advocated that an additional vein graft be placed to the distal left anterior descending artery to provide sufficient myocardial perfusion. Some evidence exists, however, that this high-flow vein might lead to competing or even backward flow through the internal thoracic artery.

METHODS

In the past 2 years, 21 patients received an additional vein graft to the distal left anterior descending artery for left internal thoracic artery hypoperfusion syndrome. Nineteen of these patients were available for magnetic resonance imaging. Early (< 6 months) and late (> 12 months) postoperative flow measurements, both in the left internal thoracic artery and in the saphenous vein grafts, were performed by means of conventional and a segmented k-space phase-contrast magnetic resonance angiography technique.

RESULTS

Early magnetic resonance examinations indicated that all conduits had adapted to the coronary flow type with predominant diastolic perfusion. Patency rate both at the early and at the late study was 100%. No concurrent flow, flow reversal, or steal phenomena were observed. Mean flow rates were 49.2 ml/min for the left internal thoracic artery and 72.6 ml/min for the saphenous vein graft.

CONCLUSION

On the basis of the flow data obtained with magnetic resonance angiography, the use of an additional saphenous vein graft as the treatment of choice in left internal thoracic artery hypoperfusion syndrome does not lead to occlusion of the artery. Conduit flow adaptation to the diastolic predominance occurs in the first 6 months after operation.

Coronary flow and coronary flow reserve measurements in humans with breath-held magnetic resonance phase contrast velocity mapping

Objective evidence for coronary lesion significance can be obtained with ischemic stress testing. Since flow-limiting stenoses have already undergone compensatory vasodilatation to maintain flow, the response to vasoactive stimulation is dampened. The degree of response limitation is reflected by the coronary flow reserve (CFR). Absolute volume flow rates can be accurately and noninvasively measured with MRI techniques. The purpose was to assess the ability to measure coronary volume flow rate noninvasively, and characterize the effect of pharmacologic stress on coronary flow quantitatively by using ultrafast, breath-held segmented k-space phase-contrast-MR imaging (PC-MRI). Ten healthy volunteers were examined by using ultrafast breath-held PC-MRI. Coronary volume flow rates were measured in the anterior descending coronary artery (LAD) at rest and following intravenous administration of dipyridamole. CFR was determined based on these data. Mean LAD volume flow rates increased from 38 +/- 11 ml/min before application of dipyridamole to 169 +/- 42 ml/min. The mean CFR amounted to 5.0 +/- 2.6 (median = 4.15). This study demonstrates the feasibility of breath-held PC-MRI to noninvasively quantify coronary volume flow rates over the cardiac cycle. Pharmacologically induced changes in volume flow rate and thus CFR can be quantitated.

MR angiography of patients with peripheral arterial disease before and after transluminal angioplasty

OBJECTIVE

This study was performed to evaluate the feasibility of using MR angiography for following up patients who have undergone interventional therapy of the infrapopliteal vascular bed.

SUBJECTS AND METHODS

Fourteen patients with peripheral vascular disease underwent MR imaging before and after percutaneous transluminal angioplasty (PTA) using a two-dimensional time-of-flight technique (TR/TE, 33/3.9; section thickness, 2.9 mm). As the gold standard, selective digital subtraction angiography was obtained for all evaluated extremities before and after PTA. For data analysis, the distal peripheral arterial system was divided into 11 segments: the popliteal artery; the tibioperoneal trunk; and the proximal, mid, and distal portions of the three trifurcation vessels. Each segment was characterized as normal, mildly diseased, moderately diseased, severely diseased, or occluded.

RESULTS

We found overall agreement between the two techniques in 110 segments (71%) and 123 segments (80%) on data obtained before and after PTA, respectively. Before PTA, our interpretation of MR angiograms overestimated 14 lesions (9%). After PTA, we overestimated five lesions (3%) on MR angiograms. We underestimated lesion severity in 30 cases (19%). The high incidence of agreement between the two techniques was reflected by the high Kendall's tau-beta values of .83 and .87 for data obtained before and after PTA, respectively.

CONCLUSION

The excellent depiction of the PTA-induced morphologic changes suggests great potential for the use of MR angiograms during interventional follow-up.

[Virtual intravascular endoscopy in the renal arteries: a new way of observing 3-D-MIR angiography data sets]

PURPOSE

To determine the potentials and limitations of a recently developed algorithm for virtual intravascular endoscopy (VIE) based on 3-dimensional (3-D) magnetic resonance (MR) data sets.

METHOD

The data from 6 patients derived from gadolinium-enhanced MR angiography of the renal arteries were reviewed. All patients had unilateral or bilateral renal arterial pathologies (stenoses n = 2, aneurysms n = 4). Imaging was performed on a 1.5-T scanner using a 3-D gradient-echo MR sequence. The imaging parameters were as follows: TR/TE/flip angle 3.9/1.9/40 degrees, matrix 256 x 192, slice thickness 1.5 to 2 mm, FOV 32 cm, and 48 slices. Image acquisition time was 28 seconds under apnoeia conditions. A total of 60 ml 0.5 molar Gd-DTPA was injected during the scan.

RESULTS

3-D data sets could be obtained in all patients and postprocessed for VIE. The intraluminal vessel wall was depicted with high clarity in all cases. All pathologies that were not intraparenchymal could be easily seen. Limitations to the technique include the image quality of the original data set, use of the ideal threshold to minimise intraluminal artifacts, and a complicated prescription sequence.

CONCLUSIONS

We have shown that VIE can be consistently performed in the renal arteries using MR data sets acquired with a contrast enhanced 3-D gradient-echo technique. It provides a hitherto unused approach to viewing 3-D vascular MR data sets.

Breath-hold, contrast-enhanced, three-dimensional MR angiography

Breath-hold gadolinium-enhanced three-dimensional magnetic resonance (MR) angiography was performed with a high-performance gradient MR imaging system in 10 volunteers with no history of vascular abnormalities (breath-hold interval, 28 seconds; repetition time, 4.0 msec; echo time, 1.9 msec; 0.4 mmol gadoterate meglumin per kilogram of body weight). High-resolution three-dimensional time-of-flight angiograms of the aorta, renal arteries, pulmonary arteries, pelvic arteries, and portal venous system were successfully acquired in all cases.

Serial myoglobin levels for patients with possible myocardial infarction

OBJECTIVES

To determine the sensitivity and specificity of a new myoglobin assay for acute myocardial infarction (AMI), considering both the total amount of serum myoglobin and its percentage change over 2 hours.

METHODS

A prospective, observational test performance study for the recognition of AMI was done using serial myoglobin assays of 42 admitted chest pain patients at a large, urban teaching hospital ED. Myoglobin testing was performed at presentation (time 0) and at 1 and 2 hours after arrival. A myoglobin level > 100 micrograms/L (ng/mL) or a change > or = 50% from baseline (increase or decrease) any time during the 2-hour period was considered positive. Patients and their physicians were blinded to the myoglobin results. The managing clinician's final diagnosis of the presenting event was used as the diagnostic criterion standard.

RESULTS

The sensitivity of the myoglobin technique for detection of AMI in the first hours in the ED was 13/14 (93%; 95% CI: 66-100%). The 1 patient who had a false-negative test had evidence of AMI on the ECG and an initially abnormal creatine kinase-MB (CK-MB) assay. The specificity was 22/28 (79%; 59-92%). However, of the 6 patients who had "false-positive" myoglobin tests, all had serious illness: significant cardiac disease (n = 4), in-hospital death (n = 1), or deep venous thrombosis (n = 1).

CONCLUSION

Myoglobin level determinations are sensitive tests to detect AMI during the first 2 hours of a patient's stay in the ED and may complement current clinical tools.

Ultra-high-speed MR imaging

Conventional magnetic resonance imaging (MRI) has been shown to provide excellent morphological images of the body organs, particularly structures undergoing little physiologic motion. Nevertheless, the clinical usefulness of MRI has been hampered by long acquisition times, high cost of scanning because of limited patient throughput, and image artifacts due to patient motion. With recent technical developments, several ultrafast scanning techniques capable of acquiring images in a breath-hold now find their introduction into clinical use. The system improvements are potentially useful for a vast range of applications hitherto not accessible to MR imaging. Among these are functional brain imaging, realtime imaging of cardiac motion and perfusion, fast abdominal imaging, improved MR angiography, and potentially real-time monitoring of interventional procedures. Whereas some ultrafast techniques can be performed on conventional scanners, echo-planar imaging, the fastest currently available data acquisition strategy, requires specially designed hardware. This article provides an overview of the technical advances in ultrafast MRI and discusses potential applications and the possible future impact on body scanning.

Human aorta: preliminary results with virtual endoscopy based on three-dimensional MR imaging data sets

PURPOSE

To determine the feasibility of use of magnetic resonance (MR) imaging data sets to perform virtual intraarterial endoscopy (VIE).

MATERIALS AND METHODS

Seven female and 14 male patients (aged 9-86 years [mean, 42 years]) with various pathologic aortic conditions underwent three-dimensional gadolinium-enhanced spoiled gradient-echo MR imaging. With prototype software, VIE postprocessing algorithms (based on ray casting) were applied to the imaging data sets. Findings at conventional angiography were used as the standards of reference.

RESULTS

The vessel wall was seen from the inside in each case, and the following pathologic conditions were depicted clearly: the two lumina in a congenial double aortic arch and the single lumen after correction, vessel narrowing in coarctations, characteristics of Leriche syndrome, stenoses, occlusions, and the true and false lumina of dissections.

CONCLUSIONS

Limitations of VIE include the image quality of the original data set, the threshold chosen to minimize intraluminal artifacts, and the inherent smoothing of vessel walls.

[Fast and ultra-fast MRI imaging of the heart]

Conventional magnetic resonance imaging (MRI) is capable of providing satisfactory morphological images of the heart and the surrounding structures. It has further evolved into a well accepted modality for functional cardiac studies such as flow quantification and volumetry. MRI has, however, been hampered by long image acquisition times. This combined with its non-real-time nature and the limited spatial resolution hs made it difficult to extend MRT to the study of small cardiac structures. Recent technical improvements have made breath-held or real-time MRI feasible and thus laid the foundations for further applications in the field of cardiovascular imaging, notably MR coronary angiography, imaging of cardiac valve leaflets, as well as first-pass perfusion studies. Moreover ultrafast MR techniques may eventually replace conventional data acquisition strategies and thus drastically increase patient throughput by shortening acquisition time. This article provides an overview of the technical advances in MRI and their application to the cardiovascular system and discusses possibilities of combined ultrafast and interventional strategies.

Real-time biplanar needle tracking for interventional MR imaging procedures

PURPOSE

To evaluate real-time biplanar tracking of a specially designed needle with magnetic resonance (MR) imaging guidance.

MATERIALS AND METHODS

The needle is made of polyetheretherketone and has a miniature radio-frequency coil incorporated into the tip. Tracking software on two workstations is used to compute three-dimensional coordinates of the coil and to display the position as a moving symbol in two imaging planes. Validation of needle tracking was performed in a harvested human liver. T2-weighted fast spin-echo images were used to target a 1-cm cyst. Success of needle placement was confirmed with aspiration and with updated gradient-recalled-echo images.

RESULTS

The cyst was successfully targeted from different approaches. Tracking procedures were monitored in real time simultaneously on two separate images.

CONCLUSION

Real-time biplanar needle tracking may prove to be useful for both diagnostic and therapeutic interventional MR imaging procedures.

In vivo reduction of bacterial populations in the urinary tract of catheterized sheep by iontophoresis

PURPOSE

Iontophoresis kills microbes in vitro and, therefore, may be a useful method for eliminating microbial populations associated with catheter-induced urinary tract infections in vivo.

MATERIALS AND METHODS

Catheters were modified to deliver current to platinum electrodes in the catheter tip. Female sheep were catheterized with this iontophoretic catheter and left ambulatory. In 5 sheep (experimental group) 400 microA was applied to the catheter and withheld in 4 sheep (control group) for 20 to 21 days. The animals were then sacrificed. During the study, types and concentrations of bacteria, and physical and chemical characteristics of the urine samples were determined.

RESULTS

Throughout the study, bacteria levels were reduced in urinary tracts of the experimental group (10(3) to 10(4) microbes per ml.) compared with the control group (10(7) microbes per ml.), without extensive alterations to urine chemistry or the sheep urinary tract.

CONCLUSIONS

Since iontophoresis safely reduced bacterial populations in catheterized sheep, this technology may reduce or eliminate nosocomial, catheter-induced urinary tract infections in humans.

Evaluation of ultrafast phase-contrast imaging in the thoracic aorta

PURPOSE

Two ultrafast phase-contrast (PC) data acquisition strategies, multishot echo-planar imaging (EPI)-PC and segmented k-space fast gradient-echo PC (FASTCARD-PC) were evaluated with regard to their measurement accuracy.

MATERIALS AND METHOD

Flow measurements of the ascending and descending aorta were acquired in 10 healthy volunteers with an electrocardiogram (ECG)-triggered eight-shot EPI-PC sequence (TR/TE/flip 16/7.4/45 degrees, 32-ms flow-phase interval, 2 x 2 mm in plane resolution), and FASTCARD-PC (six k-lines per band, TR/TE/flip 11/6.1/45 degrees, 132-ms flow-phase interval, 2 x 1 mm in plane resolution). These were compared to flow-volume data acquired with conventional cine-PC (TR/TE/flip 24/7/45 degrees, 48-ms flow-phase interval, 2 x 1 mm in plane resolution). Using cine-PC as a gold standard, the measurement accuracy of FASTCARD-PC and EPI-PC were determined.

RESULTS

Both EPI-PC and FASTCARD-PC significantly reduced data acquisition times compared to cine PC. EPI-PC flow measurements correlated well with aortic cine-PC flow-volume determinations (r = 0.98). Reflecting poorer temporal resolution, FASTCARD-PC measurements were less accurate (p < 0.05), evidenced by poor correlation with cine-PC data (r = 0.62).

CONCLUSION

Ultrafast PC measurements are possible. In contrast to the segmented k-space PC technique, which is limited in temporal resolution, multishot EPI-PC provides high measurement accuracy in pulsatile vessles while keeping the image acquisition interval short enough for a comfortable breath-hold.

Mycoplasma pneumoniae and Mycoplasma genitalium mixture in synovial fluid isolate

A mycoplasma cultured from synovial fluid specimens from a patient with pneumonia and subsequent polyarthritis was identified initially as Mycoplasma pneumoniae. In retrospective studies, the culture was shown also to contain Mycoplasma genitalium. In this paper, the laboratory techniques employed in the identification and separation of the two species are presented, and evidence to implicate postinfectious autoimmunity is provided. An increasing number of reports of M. genitalium in human tissue sites and difficulties in isolation and identification of the organism in the clinical laboratory suggest the need for more extensive application of rapid and specific detection systems for both M. genitalium and M. pneumoniae in the clinical laboratory.

[MRI venous angiography of the abdomen]

The assessment of abdominal vessels by conventional methods is invasive and frequently does not yield an accurate diagnosis, particularly in evaluation of the portal venous system. MR angiography is non-invasive and is well suited to the examination of abdominal veins. Both vessel morphology and intravascular flow patterns can be characterized with this method. Clinical indications include portal hypertension, portal vein thrombosis, portosystemic shunts as well as assessment of congenital anomalies, thrombus and tumor propagation into the inferior vena cava and the renal veins. In the future MR angiography is likely to evolve into the modality of choice for non-invasive evaluation of abdominal venous structures.

Ketorolac versus meperidine-plus-promethazine treatment of migraine headache: evaluations by patients

This study was designed to compare and contrast the speed and efficacy of meperidine (75 mg)/promethazine (25 mg) intramuscularly to ketorolac (60 mg) intramuscularly, in a double-blind study in reducing the symptoms of migraine headache. Forty-two patients who presented to the emergency department between July 1992 and February 1993, with previous diagnoses of migraine headache, were considered for this study. Patients subjectively evaluated parameters of their migraine headaches (eg, pain and nausea) using a numeric scale and were later asked to reevaluate these same parameters at 30, 60, and 360 minutes after a single intramuscular injection of either ketorolac (60 mg) or meperidine (75 mg)/promethazine (25 mg). Sixty-eight percent of patients given meperidine/promethazine responded whereas 55% of patients given ketorolac responded. The responder group showed a statistically significant reduction in headache within 30 minutes with both drug regimens. There was no statistically significant difference between the number of responders in either group. The responders from both groups had relief that lasted 6 hours after injection. In the nonresponder groups, most of the patients withdrew within 1 hour after treatment. As determined by patient response to treatment of their migraine headaches, there was no statistically significant difference between the ketorolac and the meperidine/promethazine groups.

Kidney transplantation in diabetic patients using cyclosporine. Five-year follow-up

OBJECTIVE

To review our center's experience with kidney transplantation in diabetic recipients; specifically, to compare long-term (5-year) patient and graft survival rates between diabetic and nondiabetic recipients overall and according to donor source using cyclosporine-based immunosuppression.

DESIGN

A retrospective review of all kidney transplants performed over the 7-year period from 1987 to 1993.

SETTING

A large urban tertiary care referral center with a long history of kidney transplantation and care of the diabetic patient.

PATIENTS

All patients receiving a kidney transplant, either alone or simultaneously with a pancreas transplant, were reviewed.

MAIN OUTCOME MEASURES

Actuarial patient and graft survival, serum creatinine levels, and causes of late graft loss.

RESULTS

There was no significant difference in actuarial 5-year patient or kidney graft survival between diabetic and nondiabetic recipients overall or when analyzed by donor source. There was no significant difference in mean serum creatinine levels at 5 years between diabetic and nondiabetic recipients overall or between diabetic and nondiabetic cadaveric recipients. While chronic rejection was the major cause of late graft loss in nondiabetic recipients, death with a functioning graft, principally due to cardiovascular disease, was the major cause of graft loss in diabetic recipients.

CONCLUSIONS

With cyclosporine-based immunosuppression, diabetic kidney transplant recipients have 5-year patient and graft survival rates and allograft function comparable to nondiabetic recipients. Given the high mortality of diabetic patients receiving dialysis, kidney transplantation is the treatment of choice for end-stage diabetic renal disease.

Single-shot versus interleaved echo-planar MR imaging: application to visualization of cardiac valve leaflets

Visualization of the cardiac valves with standard magnetic resonance (MR) imaging is not adequate because of long acquisition times. Echo-planar imaging (EPI) can, however, be performed with a temporal resolution (30-50 msec) comparable to that of echocardiography. The authors evaluated the feasibility of real-time imaging of cardiac valve motion with ultrafast MR techniques. Eight healthy volunteers and three patients with mitral stenosis and regurgitation were studied with a 1.5-T whole-body imager. Two different EPI sequences were assessed: a standard single-shot gradient-echo EPI (GEPI) sequence and a fast imaging technique based on multiple-shot EPI with interleaved k-space acquisition (IGEPI). Fat-suppressed images with an in-plane resolution of 3.7 x 3.7 mm were obtained equally spaced through the cardiac cycle. Half-k-space acquisition was used. Morphologic evaluation was superior with IGEPI, owing to the better intracavitary signal homogeneity (P < .01), and the mitral valve leaflets were easier to identify on systolic images. IGEPI provided adequate valve visibility in all three patients.

Quantification, qualification, and microbial killing efficiencies of antimicrobial chlorine-based substances produced by iontophoresis

The dependence of microbial killing on chloride ions present in solutions undergoing iontophoresis is addressed. A 400-microA current was applied to vials containing synthetic urine or saline, and the production of chlorine-based substances (CBSs) was detected by the N,N-diethyl-p-phenylene diamine colorimetric method. It was found that as the time of current application increased, the total concentration of CBSs also increased. The iontophoretic current converted (through oxidation) chloride ions present in the solutions into CBSs such as free chlorine, chlorine dioxide, chlorite, monochloramine, and dichloramine (the last two were produced by iontophoresis only when nitrogenous substances were present in the solution). Two of the CBSs (free Cl and ClO2), when they were separately added back to microbial suspensions (approximately 3 x 10(5) CFU/ml) at the same concentrations at which they were detected in either 0.46% (wt/vol) NaCl solution or synthetic urine iontophoresed for 4 h at 400 microA, reduced or eliminated bacterial genera and a fungus. However, when free Cl and ClO2 were jointly added back to microbial suspensions, bacterial and fungal killing was synergistic and more rapid and complete than when these chlorine-based biocides were added separately. Therefore, iontophoresis of solutions containing chloride ions produces chlorine-based biocides that are responsible for the antimicrobial effect of iontophoresis.

[MR angiography of pelvic and abdominal vessels]

The assessment of abdominal vessels with conventional methods is invasive and frequently does not yield an accurate diagnosis, particularly in the evaluation of the portal venous system. MR angiography is non-invasive and is well suited for the examination of abdominal vessels. Both vessel morphology and intravascular flow patterns can be characterized with this method. Clinical indications include portal hypertension, portal vein thrombosis, portosystemic shunts, assessment of congenital anomalies, thrombus, and tumor propagation into the inferior vena cava and the renal veins, proximal renal artery stenosis, and assessment of the pelvic arteries and veins. In the future, MR angiography may become an important part of the non-invasive evaluation of abdominal and pelvic vessels.

Normal heart: evaluation with echo-planar MR imaging

PURPOSE

To evaluate the appearance of the heart on spin-echo (SE) and gradient-echo (GRE) echo-planar magnetic resonance (MR) images.

MATERIALS AND METHODS

Nine healthy volunteers were examined with an MR imager with transaxial echo-planar imaging (EPI) capabilities. SE EPI and GRE EPI sequences were used. Full k-space signal was obtained with readout time of 40 msec per image, and total image acquisition time was 72 and 52 msec, respectively, for SE EPI and GRE EPI.

RESULTS

Delineation of cardiac structures was superior with SE EPI, reflective of significantly higher contrast between myocardial and intraluminal signal intensity (SI) (P < .001). The higher (P < .01) and more homogeneous (P < .001) intraluminal SI with GRE EPI allowed better assessment of intracardiac flow. Septal SI was significantly higher for GRE EPI (P < .01), but signal homogeneity was similar for both sequences (P > .2).

CONCLUSION

Diagnostic images of the heart were obtained with both SE EPI and GRE EPI. GRE EPI is more suitable for flow studies because of the higher and more homogeneous intravascular SI.

Ketorolac as a rapid and effective treatment of migraine headache: evaluations by patients

The objective of this study was to determine the speed and efficiency of ketorolac in reducing the symptoms of migraine headache. Twenty-three patients who presented in the emergency department during the period between April and July 1992 with a previous diagnosis of migraine headache were considered for the study. Patients subjectively evaluated parameters of their migraine headaches (eg, pain and nausea) with a numerical scale and were asked to re-evaluate these same parameters at 30, 60, and 360 minutes after a single injection of Ketorolac. Seventeen (74%) patients reported a decrease in headache symptoms that was significant (P < .005) after 1 hour. Relief lasted at least 6 hours after injection.

Bungee jumper's foot drop peroneal nerve palsy caused by bungee cord jumping

Peroneal nerve injury is a common peripheral neuropathy from a variety of conditions and injuries. We encountered a case of peroneal nerve palsy in a professional bungee cord jumper. Review of the literature showed no previous report of this particular injury in bungee cord jumping.

[Trichomegaly in HIV infection]

Hypertrichosis of the eyelashes was first described as "trichomegaly" in the setting of rare congenital syndromes. Recently numerous cases of acquired trichomegaly of the eyelashes have been described, especially in patients with advanced human immunodeficiency virus type I infection. The pathomechanisms leading to acquired trichomegaly remain largely unknown. Direct effects of the virus on the hair follicle, immune dysregulation, and a multifactorial pathogenesis are discussed. We report a case of acquired trichomegaly in advanced HIV-I infection in order to present this unusual clinical finding and other hair problems in AIDS patients. It is suggested that acquired trichomegaly of the eyelashes may act as a useful clinical marker for assessment of severity of HIV-I infection.

Iontophoresis and chloride-containing compounds: parameters required for killing

Fungi, and gram-positive and gram-negative organisms were susceptible to iontophoretic killing in simple media. Iontophoresis did not depend on electrode type but did require chloride-containing compounds in the medium. All organisms could be killed efficiently if chloride-containing compounds (for example sodium chloride and calcium chloride) were present in physiological concentrations. Effectiveness of iontophoretic killing could be reduced by nonphysiologically elevated concentrations of other substances (for example creatinine and albumin). The data suggest that iontophoresis should function well in urine, since chloride-containing compounds are present in adequate concentrations even if some naturally occurring compounds, such as creatinine or albumin, are elevated.

Iontophoresis generates an antimicrobial effect that remains after iontophoresis ceases

Iontophoresis required chlorine-containing compounds in the medium for effective microbial population reduction and killing. After iontophoresis ceased, the antimicrobial effect generated by iontophoresis remained but slowly decreased. Antimicrobial effects of iontophoresis may be related to the generation of short-lived chlorine-containing compounds.

Electrode and bacterial survival with iontophoresis in synthetic urine

Urinary catheters, especially in patients with long-term catheter requirements, frequently are a source of infection. Iontophoresis has been proposed as a method to decrease or eliminate such infections. Several types of material were examined for their potential use as electrodes in an iontophoretic catheter system. Silver, copper and nickel electrodes did kill microorganisms but did not show longevity. Carbon and gold electrodes showed longevity and killing of microorganisms. Gold proved to be somewhat better than carbon in killing Klebsiella pneumoniae in a broth. Few organisms survived iontophoresis. Those few that survived (mainly Klebsiella in broth), when rechallenged by iontophoresis, did not show any striking resistance to iontophoresis. Our data support the proposition that inclusion of electrodes, depending on the electrode type, in a catheter probably will decrease or eliminate a bacterial population in urine and, thus, may help prevent catheter-related infections and their sequelae.

Bacterial and fungal killing by iontophoresis with long-lived electrodes

Iontophoresis with gold, carbon, and platinum electrodes was shown to effectively reduce or eliminate gram-positive, gram-negative, and Candida albicans inocula in synthetic urine. Platinum and gold electrodes were more effective than carbon electrodes, but platinum showed the best longevity and may reduce or eliminate microbial colonization of catheters.

Urothelial hyperplasia and neoplasia. III. Detection of nitrosamine production with different bacterial genera in chronic urinary tract infections of rats

Various agents have been implicated in inducing urothelial cancer. Although drugs, occupational and environmental carcinogens are more widely accepted as playing a major role as urothelial carcinogens, several investigations suggest that bacteria may play a role. The mechanism of how bacteria may interact with the host to augment the development of urothelial carcinoma is not well understood. Clinically, investigators have linked the development of infection, urinary stones and indwelling catheters with urothelial cancer. Other investigators have suggested that the mechanism may be related to the production of carcinogenic compounds (nitrosamines) which can be detected during urinary tract infection. In our laboratory, we showed that rats with chronic urinary tract infections produced increasing urinary levels of N,N dimethylnitrosamine over a 24 week period and that the production correlated with hyperplasia and early neoplasia of the bladder epithelium. Three bacterial genera were used and two of these (Escherichia coli and a protein sp.) showed production of increasing levels of urinary nitrosamine and correlated with infection. The purpose of this current study is to determine if other bacterial genera and strains can also produce similar increasing nitrosamine levels in the rat model of chronic urinary tract infection and thus provide evidence that a number of bacterial genera and strains can produce nitrosamines in vivo. Also, the histology of the chronically infected bladder was examined for hyperplasia and neoplasia.

Serum and urinary immunoglobulin in the rat model of acute urinary tract infection

Total levels of urine and serum immunoglobulin IgM, IgG and IgA, and the E. coli-specific bacterial immunoglobulin response were determined by enzyme-linked immunosorbent assay (ELISA) in a rat model of acute urinary tract infection. High levels of urinary IgM were detected as early as day 3 post infection and then decreased to statistically insignificant levels. Peak levels of IgG occurred in the serum and urine on day 14. Urine and serum IgA levels remained low throughout the study period. The results demonstrate that in the rat model of acute urinary tract infection, IgM appears first in the urine and serum, and rapidly decreases. IgG then appears in the serum and urine followed by a late E. coli-specific immunoglobulin serum and urine response. Also, a non-specific component of the immunoglobulin response was noted in both the serum and urine. In the rat, IgA appears to play little or no role in the urine or in the serum response to the infection.

Effects of microamperage, medium, and bacterial concentration on iontophoretic killing of bacteria in fluid

Prevention of nosocomial urinary tract infections by iontophoresis is addressed. An iontophoretic generator was used to provide microamperage (10 to 400 microA) to vials containing either synthetic urine or supplemented synthetic urine. Bacteria were added to vials, and parameters of growth, bacterial killing, and multiple electrode materials were examined. Escherichia coli and Proteus species were both inhibited and killed at various microamperages and with several electrode types, the most efficient being gold-gold as the anode-cathode combination. Klebsiella pneumoniae in supplemented synthetic urine was least inhibited in growth, and higher microamperage (200 to 400 microA) was most effective in killing the bacteria. Bacterial growth reduction and killing were directly related to increasing microamperage and were inversely related to bacterial concentration.

Isolation of Mycoplasma pneumoniae from synovial fluid samples in a patient with pneumonia and polyarthritis

A patient with a long history of arthritis developed pneumonia. Two weeks into her hospital course, the patient developed effusions in her knee and wrist that yielded cultures positive for Mycoplasma pneumoniae. To our knowledge, this is the third reported case of M pneumoniae isolation from a joint and the first report of isolation of M pneumoniae from two joints in a patient without hypogammaglobulinemia. The evidence suggests that in individuals with atypical pneumonia and joint effusions, M pneumoniae should be considered as a source of infection.

Acute and chronic bacterial infection in the rat urinary tract: immunofluorescent localization of immunoglobulins

To study the relative concentrations and appearance of immunoglobulin in the bladder and kidneys of rats with acute and chronic urinary tract infections, three groups of female Sprague-Dawley rats were studied. Group I underwent weekly intraurethral inoculation with Escherichia coli 07. Group II received inoculation of 0.2 ml of PBS alone. Group III were unmanipulated controls. Bladder and kidney washings were obtained for bacterial colony counts and organism identification. Bladder and kidney tissue was prepared for immunofluorescent examination using goat or rabbit antirat IgA, IgM, or IgG layered with fluorescent-labeled rabbit antigoat or goat antirabbit serum. Negative immunofluorescent controls substituted PBS for antirat serum. No significant difference was noted between bladder and kidney cultures in groups I and II. Comparison of immunofluorescent intensity between groups I and III demonstrated that IgM intensity was greatest between weeks one and three in bladders and kidneys, then decreased to non-significant levels. Bladder IgG intensity peaked at week four and remained elevated throughout the remainder of the study while renal IgG intensity was significant throughout the study period. Renal and bladder IgA was noted only sporadically. Comparison of culture positive animals to culture negative animals (groups II and III) demonstrated a lower immunofluorescent intensity score for culture negative animals. Discrete cellular immunofluorescence was evident in 19.1% of bladders and compared to 0.6% of kidneys. This study suggests that the immunologic response in the rat to intraurethral inoculation and infection is biphasic (IgM followed by IgG) and that a local cellular immunologic response may exist in the bladder.

Total and specific immunoglobulin response to acute and chronic urinary tract infections in a rat model

Total and specific levels of immunoglobulins IgG, A and M were determined by an enzyme-linked immunosorbent assay (ELISA) in a rat model of urinary tract infections (cystitis) during the early and late phases of infection. The early response was characterized by rapid rise in IgM in serum and urine. This response decreased rapidly and was undetectable in urine after eight weeks. Correlation between total serum and urine levels of IgM was not found although a chronological relationship was observed. Total and specific serum and urine IgA responses were erratic. Concentrations of IgA were low and this antibody class was undetectable in urine until the infection had been established for six weeks. In contrast, total serum and urine IgG increased in concentration at five days post infection and reached total maximum by weeks four to eight, then declined, but remained detectable over 24 weeks. Specific IgG titers remained elevated in serum but declined in urine between four and 10 weeks. A correlation between total serum and total urine IgG was found. Also, bacteria generated a concomitant nonspecific response, a part of which was detected against a common antigen expressed on E. coli J5 strain that cross-reacts with a number of gram negative genera. The results show that IgM chronologically is the first antibody to appear in increased amounts in the serum and urine, followed by IgG. The data also suggests a relationship exists between total serum IgG and total urine IgG which may affect the host's ability to eliminate urinary infection.

Urinary carcinogen [nitrosamine] production in a rat animal model for ureterosigmoidostomy

Tumor development at the site of ureterointestinal anastomosis is a recognized complication in patients undergoing ureterosigmoidostomy. In order to explore the hypothesis that carcinogens (nitrosamines) may be a factor in ureterosigmoidostomy, female Sprague-Dawley rats (n = 125) underwent urethral ligation, bladder dome resection and anastomosis of the bladder trigone to an opening in the anterior rectosigmoid wall. Biweekly nitrosamine determinations were performed on the resultant urine-feces slurry by gas chromatography up to thirty-two weeks post surgery. Nitrosamine (N,N-dimethylnitrosamine) was noted as early as two weeks after surgery in 39% (11/28) of rats. One hundred percent of animals consistently demonstrated nitrosamine by week 14 (32 rats). Nitrosamine levels increased throughout the study with a peak level after thirty-two weeks of 0.275 micrograms./ml. Only a portion (n = 40) of the total animal population was deemed suitable for pathologic examination secondary to animal demise and autolysis at autopsy related to infection and obstruction. In these animals, no adenocarcinoma was found although hyperplastic changes and metaplastic changes were demonstrable at nine days and eight weeks respectively. In one animal a grade I transitional cell papilloma was identified after eight weeks. Control animals demonstrated no nitrosamine production. In vitro combinations of rat urine and feces yielded nitrosamine after six weeks. The absence of adenocarcinoma tumor development is believed indirectly related to animal demise in that not enough time had elapsed to allow significant tumor development. This study lends support to the concept that nitrosamines may play a role in the development of hyperplasia, dysplasia and eventual neoplasia in ureterosigmoidostomy.

Combined effects of hyperbaric oxygen and antifungal agents on the growth of Candida albicans

The effects of hyperbaric oxygen (HBO) and antifungal agents on Candida albicans were studied. Growth curves at O2 tensions of 160 mm Hg, 900 mm Hg, and 1800 mm Hg for prolonged exposures showed no effect of pressure alone. There was a significant dose response to increasing O2 tension; growth inhibition occurred at 900 mm Hg O2 and killing at 1800 mm Hg O2. Minimum inhibitory concentrations (MIC) and minimum cidal concentrations (MCC) at 160 and 900 mm Hg O2 were done using amphotericin B, nystatin, clotrimazole, miconazole, ketoconazole and 5-fluorocytosine. MIC and MCC's were done with amphotericin B at 90-min exposures to 1800 mm Hg O2. There was no enhancement of MIC or MCC at 900 mm Hg O2. However, ketoconazole was ineffective at killing at 900 mm Hg O2 indicating a protective effect of HBO with this drug. Oxygen tensions of 1800 mm Hg for 90 min in the presence of amphotericin B showed an enhancement of both MIC and MCC. Closer quantitation of this effect upon the in vitro growth and survival of the organism showed an additive but not synergistic effect.