Primary Adrenal Epithelioid Angiosarcoma: A Case Report

Primary adrenal angiosarcomas are exceedingly rare with a rapidly progressive clinical course and a poor outcome. Establishing the diagnosis can be challenging, and it is complicated by the fact that there are no characteristic clinical or imaging features that are pathognomonic for angiosarcoma. Histologically, they can overlap with other more commonly encountered adrenal tumors. Herein, we present an otherwise healthy 41-year-old woman diagnosed with a primary adrenal epithelioid angiosarcoma. We aim to expand the knowledge of the sparse literature existing on primary adrenal angiosarcomas to help better understand the diagnostic features, clinical behavior, and management of these rare tumors.

Comparative histologic features among liver biopsies with biliary-pattern injury and confirmed clinical diagnoses

Biliary-pattern injury in the liver (eg, duct injury, ductular reaction, cholestasis) can occur in several conditions, including primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), large duct obstruction (LDO), and drug-induced liver injury (DILI). While the histologic changes in these conditions have been individually well described, distinguishing among them remains often challenging, particularly when biopsy samples are limited in size, robust clinical information is unavailable, and/or the pathologist does not feel confident in evaluating liver disease. This study evaluated histologic features that could aid the diagnosis of biliary-pattern injury on biopsy. We reviewed 121 liver biopsies from clinically confirmed cases of PBC, PSC, chronic LDO, or DILI for multiple clinical and histologic parameters. The rates of these histologic findings were then compared among different entities. Onion-skin fibrosis was seen in 14% of PSC in comparison to 0%, 5%, and 0% of PBC, DILI, and chronic LDO (P = 0.031). Florid duct lesions were identified in 21% of PBC compared to 2% of PSC and 0% of DILI and LDO (P = 0.0065). Similarly, 42% of PBC showed lobular granulomas, compared to 7% of PSC, 11% of DILI, and 33% of chronic LDO (P = 0.0001). Cholestasis was more commonly seen in DILI (42%) and chronic LDO (83%) than in PBC (4%) and PSC (16%) (P < 0.0001). Lobular chronic inflammation was found in a significantly higher percentage of PBC and LDO than of PSC and DILI (P = 0.0009). There were significantly fewer cases of PBC showing neutrophils in ductular reaction than PSC, DILI, and LDO (P = 0.0063). Histologic findings that can help suggest a diagnosis in liver biopsies with biliary-pattern injury include florid duct lesions, lobular granulomas, lack of neutrophils in ductular reaction, and lobular chronic inflammation in PBC; onion-skin fibrosis in PSC; cholestasis and feathery degeneration in DILI; and lobular granulomas, lobular chronic inflammation, cholestasis, and feathery degeneration in chronic LDO. These findings are likely most helpful when complicating factors interfere with biopsy interpretation.

Erroneous Patient Tissue Contaminants in 1574 Surgical Pathology Slides: Impact on Diagnostic Error and a Novel Framework for Floater Management

CONTEXT.—

Tissue contaminants on histology slides represent a serious risk of diagnostic error. Despite their pervasive presence, published peer-reviewed criteria defining contaminants are lacking. The absence of a standardized diagnostic workup algorithm for contaminants contributes to variation in management, including investigation and reporting by pathologists.

OBJECTIVE.—

To study the frequency and type of tissue contaminants on microscopic slides using standardized criteria. Using these data, we propose a taxonomy and algorithm for pathologists on "floater" management, including identification, workup, and reporting, with an eye on patient safety.

DESIGN.—

A retrospective study arm of 1574 histologic glass slides as well as a prospective study arm of 50 slide contamination events was performed. Using these data we propose a structured classification taxonomy and guidelines for the workup and resolution of tissue contamination events.

RESULTS.—

In the retrospective arm of the study, we identified reasonably sized benign tissue contaminants on 52 of 1574 slides (3.3%). We found size to be an important parameter for evaluation, among other visual features including location on the slide, folding, ink, and tissue of origin. The prospective arm of the study suggested that overall, pathologists tend to use similar features when determining management of potentially actionable contaminants. We also report successfully used case-based ancillary testing strategies, including fluorescence in situ hybridization analysis of chromosomes and DNA fingerprinting.

CONCLUSIONS.—

Tissue contamination events are underreported and represent a patient safety risk. Use of a reproducible classification taxonomy and a standardized algorithm for contaminant workup, management, and reporting may aid pathologists in understanding and reducing risk.

The role of the adenosine triphosphate-sensitive potassium channels in pinacidil-induced vasodilatation of the human saphenous vein in patients with and without type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) increases cardiovascular complications. Diabetic vascular dysfunction is associated with the reduced activity of the different smooth muscle potassium (K⁺) channels. Thus, the objective of our study was to investigate the role of the adenosine triphosphate (ATP)-sensitive K⁺ (K_ATP) channels in the relaxant effect of potassium channel opener, pinacidil on the human saphenous vein (HSV) obtained from the patients with and without T2DM. The rings of HSV without the endothelium, obtained from the patients who had undergone coronary bypass surgery, were mounted in an organ bath system and isometric tension was recorded. The relaxation of HSV, precontracted with phenylephrine, was produced by pinacidil. The expression of K_ATP subunits (Kir6.1, Kir6.2 and SUR2B) was detected by immunohistochemistry and Western blot. Pinacidil produces comparable effects on HSV in patients with and without T2DM. The suppression of pinacidil effect and its maximal relaxation by glibenclamide, selective blocker of K_ATP channels, was more pronounced on HSV in patients without T2DM. All three types of K_ATP subunits are expressed on the smooth muscle cells of HSV. While there are no differences in the expression of Kir6.1 and Kir6.2, the expression of SUR2B is lower in HSV in patients with T2DM. Pinacidil produced comparable K_ATP-dependent and -independent relaxation of the HSV in patients with/without T2DM. According to the effect of glibenclamide and the applied molecular analysis, presented findings demonstrated that diabetes mellitus was associated with the reduced expression of SUR2B subunit in the vascular smooth muscle of HSV.

Predictors of competitive achievement among pubescent synchronized swimmers: an analysis of the solo-figure competition

AIM

This study examined the applicability of sport-specific fitness tests (SSTs), anthropometrics, and respiratory parameters in predicting competitive results among pubescent synchronized swimmers.

METHODS

A total of 25 synchronized swimmers (16-17 years; 166.2 ± 5.4 cm; and 58.4 ± 4.3 kg) volunteered for this study. The independent variables were body mass, body height, Body Mass Index (BMI), body fat percentage (BF%), lean body mass percentage, respiratory variables, and four SSTs (two specific power tests plus one aerobic- and one anaerobic-endurance test). The dependent variable was competitive achievement in the solo figure competition. The reliability analyses, Pearson's correlation coefficient and forward stepwise regression were calculated.

RESULTS

The SSTs were reliable for testing fitness status among pubescent synchronized swimmers. The forward stepwise regression retained two SSTs, BF% and forced vital capacity (FVC, relative for age and stature) in a set of predictors of competitive achievement. Significant Beta coefficients are found for aerobic-endurance, SST and FVC.

CONCLUSION

The sport-specific measure of aerobic endurance and FVC appropriately predicted competitive achievement with regard to the figures used in the competition when competitive results (the dependent variable) were obtained. Athletes and coaches should be aware of the probable negative influence of very low body fat levels on competitive achievement.

Honey bee (Apis mellifera) venom induces AIM2 inflammasome activation in human keratinocytes

BACKGROUND

Following allergen exposure, cytokines and other pro-inflammatory signals play an important role in the immunological cascade leading to allergic sensitization. Inflammasomes sense exogenous and endogenous danger signals and trigger IL-1β and IL-18 activation which in turn shape Th2 responses. Honey bee venom (BV) allergies are very common; however, the local inflammatory cascade leading to the initiation of allergic sensitization is poorly understood. In this study, the local inflammatory cascades in skin after exposure to BV were investigated.

METHODS

The mechanisms of inflammasome activation in human skin and in cultured keratinocytes upon BV exposure were analyzed by ELISA, Western blot, flow cytometry, siRNA techniques, and immunofluorescence.

RESULTS

In an ex vivo bee sting model, BV induced IL-1β release suggesting the activation of inflammasomes. Indeed, in cultured keratinocytes, the BV component melittin triggered IL-1β and IL-18 release via the AIM2 inflammasome. AIM2 is a cytosolic DNA receptor, and mitochondrial as well as genomic DNA was detected in the cytosol of melittin-treated keratinocytes as triggers of inflammasome activation. As a mechanism, melittin mediated destruction of mitochondrial membranes leading to the leakage of mitochondrial DNA into the cytosolic compartment.

CONCLUSION

These data suggest that upon BV exposure, keratinocytes are involved in an innate immune response by the activation of the AIM2 inflammasome and subsequent IL-1β and IL-18 release triggered by endogenous DNA. As IL-1β and IL-18 are involved in Th2- and IgE-mediated immune reactions, these results could add to the understanding of the role of the tissue microenvironment to subsequent allergic responses.

Narrowband ultraviolet B treatment improves vitamin D balance and alters antimicrobial peptide expression in skin lesions of psoriasis and atopic dermatitis

BACKGROUND

Narrowband ultraviolet B (NB-UVB) is a routine treatment for psoriasis and atopic dermatitis (AD) but its effect on vitamin D balance is not well studied.

OBJECTIVES

To examine whether NB-UVB treatment in winter improves vitamin D balance in psoriasis and AD, and to study the effects of NB-UVB on antimicrobial peptide and cytokine expression in the skin.

METHODS

Eighteen adult patients with psoriasis, 18 with AD and 15 healthy subjects received a total of 15 NB-UVB exposures on the whole body, given three times a week. Serum calcidiol (25-hydroxyvitamin D) was measured by radioimmunoassay. Antimicrobial peptide and cytokine expression in skin lesions was examined by real-time quantitative polymerase chain reaction.

RESULTS

At onset 16 (89%) patients with psoriasis, 17 (94%) patients with AD and eight (53%) healthy subjects had vitamin D insufficiency (calcidiol < 50 nmol L(-1)). NB-UVB treatment significantly increased (P < 0.001) serum calcidiol. The increase was 59.9 nmol L(-1) (95% confidence interval, CI 53.5-66.9) in psoriasis, 68.2 nmol L(-1) (95% CI 55.4-80.1) in AD and 90.7 nmol L(-1) (95% CI 63.8-123.4) in healthy subjects. Psoriasis Area and Severity Index and SCORAD improved significantly (P < 0.001) but no correlation to the increase of serum calcidiol was found. Cathelicidin and human beta-defensin 2 (HBD2) expression was high in skin lesions of psoriasis. After six NB-UVB treatments cathelicidin increased further while HBD2 expression decreased. A similar trend was observed in AD lesions. NB-UVB caused a marked but nonsignificant decrease of interleukin (IL)-1beta and IL-17 in psoriasis lesions.

CONCLUSIONS

The present study shows that in addition to a significant improvement of psoriasis and AD, NB-UVB treatment effectively corrects vitamin D insufficiency. It also increases cathelicidin and decreases HBD2 levels in healing skin lesions of psoriasis and AD. This effect might be mediated by improved vitamin D balance and the local cytokine network.

[Cathelicidins: multifunctional defense molecules of the skin]

The human skin is constantly exposed to microbial pathogens but infections only rarely occur. Innate cutaneous immunity is a primary system for protection against infection, and antimicrobial peptides (AMPs) expressed in skin are essential defence molecules. The AMPs include molecules such as the defensins that were first characterized for their antimicrobial properties as well as other peptides and proteins first known for their activity as chemokines, enzymes, enzyme inhibitors and neuropeptides. Cathelicidins are unique AMPs that act as defensive and signalling molecules. Two different pathways are involved in this function: cathelicidins have direct antimicrobial activity and they also initiate a host of cellular responses in cytokine release, inflammation and angiogenesis. Several skin diseases are associated with cathelicidin dysfunction. In atopic eczema, for example, cathelicidin expression is suppressed, whereas in rosacea cathelicidin peptides are abnormally processed to forms that induce cutaneous inflammation and a vascular response. In psoriasis cathelicidin peptide converts self-DNA to a potent stimulus in an autoinflammatory cascade. Current studies have unexpectedly identified vitamin D3 as a major factor for the regulation of cathelicidin expression. This finding may provide new strategies in the management of infectious and inflammatory diseases of the skin by targeting control of the expression and function of cathelicidin and other AMPs.

[Selective digestive decontamination. Why don't we apply the evidence in the clinical practice?]

Selective digestive decontamination (SDD) is a prophylactic strategy whose objective is to reduce the incidence of infections, mainly mechanical ventilation associated pneumonia in patients who require intensive cares, preventing or eradicating the oropharyngeal and gastrointestinal carrier state of potentially pathogenic microorganisms. Fifty-four randomized clinical trials (RCTs) and 9 meta-analysis have evaluated SDD. Thirty eight RCTs show a significant reduction of the infections and 4 of mortality. All the meta-analyses show a significant reduction of the infections and 5 out of the 9 meta-analyses report a significant reduction in mortality. Thus, 5 patients from the ICU with SDD must be treated to prevent pneumonia and 12 patients from the ICU should be treated to prevent one death. The data that show benefit of the SDD on mortality have an evidence grade 1 or recommendation grade A (supported by at least two level 1 investigations). The aim of this review is to explain the pathogeny of infections in critical patients, describe selective digestive decontamination, analyze the evidence available on it efficacy and the potential adverse effects and discuss the reasons published by the experts who advise against the use of SDD, even though it is recognized as the best intervention evaluated in intensive cares to reduce morbidity and mortality of the infections.

Pro-atrial natriuretic peptide hormone from right atria is correlated with cardiac depression in septic patients

N-terminal pro-atrial natriuretic peptide [proANP(1-98)] has been extensively investigated in patients with chronic heart failure and ishemic heart disease. It is found to be a better marker of cardiac dysfunction than atrial natriuretic peptide (ANP). The possible involvement of proANP(1-98) in cardiac depression caused by sepsis has not been studied yet. Therefore, we analyzed atrial plasma concentration of proANP(1-98) in 17 septic patients with hemodynamic variables measured or calculated using pulmonary artery catheter. The results of altogether 96 measurements show a significant negative correlation of proANP(1-98) and cardiac index (p<0.024), oxygen delivery (p<0.03) and oxygen consumption (p<0.03). There is also a positive correlation with pulmonary vascular resistance (p<0.03). ProANP(1-98) is significantly higher in patients who developed acute respiratory distress syndrome (ARDS) (p<0.001). This study implies that proANP(1-98) is a possible novel hormone marker of cardiac depression caused by sepsis that could be used for prediction of ARDS.

Tension-free left ITA graft -- the pericardial strip technique

Emphysematous lung occupying the whole dome of the left pleural cavity and expanding well over the midline may occasionally present a significant problem for positioning of the left internal thoracic artery, although the graft has been mobilized up to its origin. To avoid an undue tension on it, we combined a well known technique of the pericardial incision with the pericardial strip technique, enabling the lung to expand freely.

Ab Initio Investigation of the ellipsis pi(2)(g) (X(3)Sigma(-)(g), 1(1)Delta(g), 1(1)Sigma(+)(g)) Electronic States of NCN. Study of the Renner-Teller Effect in the 1(1)Delta(g) State

Large-scale CI calculations are carried out to obtain accurate potential energy surfaces for the ellipsis pi(2)(g) manifold (X(3)Sigma(-)(g), 1(1)Delta(g), 1(1)Sigma(+)(g)) of electronic states of NCN. Separation of the low-lying singlet states from the triplet ground state is computed in close agreement with the results of a recent photoelectron study by T. R. Taylor, R. T. Bise, K. R. Asmis, and D. M. Neumark [Chem. Phys. Lett. 301, 413-416 (1999)]. Vibronic coupling (Renner-Teller effect) in the 1(1)Delta(g) state is studied by means of a perturbative and a variational approach. Results of the present ab initio study confirm explicitly the rho(4) dependence postulated for the splitting of bending potential curves in Delta electronic states at small deviations from linearity. Copyright 2000 Academic Press.

Laparoscopic cholecystectomy and perioperative ERCP

BACKGROUND/AIMS

Study of acceptance of simultaneous laparoscopic cholecystectomy and endoscopic retrograde cholangiopancreatography for treatment of cholelithiasis with choledocholithiasis.

METHODOLOGY

There were 25 patients. Ten patients had acute pancreatitis of biliary etiology, accompanied by transitory icterus. In 15 patients, choledocholithiasis was suspected preoperatively both on ultrasonography and i.v. cholangiography. In all patients laparoscopic cholecystectomy with perioperative endoscopic retrograde cholangiopancreatography and sphincterotomy were performed for the treatment of cholelithiasis and choledocholithiasis.

RESULTS

Simultaneous laparoscopic cholecystectomy and endoscopic retrograde cholangiopancreatography was successfully done in all patients. The patients were discharged home on the 4th day after the surgery. Concerning early complications, there where 3 early complications, e.g., prolonged hemorrhage after papillotomy in a patient with choledocholithiasis with stenotic papillitis. Conservative therapy (fresh frozen plasma, local hemostats) was used in this patient. In 4 patients with choledocholithiasis, transitory hyperamylasemia was observed, with no clinical symptoms of pancreatitis. The symptoms disappeared with conservative therapy 3 days after the beginning of treatment.

CONCLUSIONS

Simultaneous laparoscopic cholecystectomy and endoscopic retrograde cholangiopancreatography for treatment of cholelithiasis and choledocholithiasis is a safe and acceptable treatment.

Aziridinyl peptides as inhibitors of cysteine proteases: effect of a free carboxylic acid function on inhibition

Peptides containing aziridine-2,3-dicarboxylate (Azi) as electrophilic building block are evaluated as inhibitors of the cysteine proteases papain, cathepsin B, cathepsin L and clostripain. The influence of a free carboxylic acid as functional group at different positions of the inhibitor molecule on inhibition is analyzed. Structure-activity relationships and binding mode hypotheses are discussed. In contrast to the bacterial enzyme clostripain, the papain like mammalian proteases (cathepsins) are irreversibly inactivated by aziridinyl peptides. N-Unsubstituted aziridines are much more potent inhibitors of papain and cathepsins if they contain the free carboxylic acid attached to the aziridine ring (HOAzi-Leu-ProOBzl). Two free carboxylic acid functions at the aziridine ring are necessary for good inhibition of these enzymes by N-acylated aziridinyl peptides (BOC-Phe-Azi(OH)2). Chimeric bispeptidyl derivatives are selective CB inhibitors if the free acid is located at the C-terminus of the peptide (BOC-Phe-(EtO)Azi-Leu-ProOH). Clostripain is only inhibited by aziridinyl peptide esters.

Diminished aqueous microviscosity of tumors in murine models measured with in vivo radiofrequency electron paramagnetic resonance

Using very low frequency in vivo electron paramagnetic resonance (EPR), we have compared, for the first time, the average microviscosity of the total aqueous compartment of murine fibrosarcomas and that of normal leg tissue in a living animal. EPR spectra from dissolved nitroxide spin probes report the solvent microviscosity. The tumor aqueous microviscosity, 1.8 +/- 0.1 centipoise, was significantly lower than that of the corresponding normal tissue, 2.9 +/- 0.3 centipoise, a difference of 38 +/- 7%. These results confirm the commonly observed increase in the water proton transverse relaxation times (T2) in magnetic resonance imaging of hyperproliferative states, for example, malignancy. The specificity of the localization of the EPR signal indicates a substantial portion of the T2 increase seen in magnetic resonance imaging derives from decreased bulk-water viscosity. The effect of this microviscosity differences may be the basis of several physiological differences between tumors and normal tissues which could confer a growth rate advantage to tumor tissue.

Probing DMPG vesicle surface with a cationic aqueous soluble spin label

A small, highly aqueous soluble, deuterated, cationic spin label, 4-trimethylammonium-2,2,6,6-tetramethylpiperidine-d17-1-oxyl iodide (dCAT1), was used to directly monitor the negatively charged DMPG vesicle surface in order to test a recent suggestion (Riske et al., Chem. Phys. Lipids, 89 (1997) 31-44) that alterations in the surface potential accompanied apparent phase transitions observed by light scattering. The temperature dependence of the label partition between the lipid surface and the aqueous medium indicated an increase in the surface potential at the gel to liquid-crystal transition, supporting the previous suggestion. Results at the phase transition occurring at a higher temperature were less definitive. Although some change in the dCAT1 ESR spectra was observed, the interpretation of the phenomena is still rather unclear. DMPG surface potentials were estimated from the dCAT1 partition ratios (surface label moles/total label moles), using a simple two-sites model, where the electrostatic potential is zero everywhere but at the vesicle surface, and the interaction between the spin label and the membrane surface is chiefly electrostatic. The Gouy-Chapman-Stern model predicts surface potentials similar to those observed, although the measured decrease in the surface potential with ionic strength is somewhat steeper than that predicted by the model.

Contributions to the Gaussian line broadening of the proxyl spin probe EPR spectrum due to magnetic-field modulation and unresolved proton hyperfine structure

A simple expression is derived to compute the total Gaussian linewidth of a Voigt line that is broadened by sinusoidal magnetic-field modulation as follows: delta HPPG(Hm)2 = delta HPPG(0)2 + kappa 2Hm2, where delta HPPG(Hm) is the Gaussian linewidth observed with an modulation amplitude Hm/2 and delta HPPG(0) is the Gaussian linewidth in the limit of zero modulation. The field modulation contributes an additional Gaussian broadening of kappa Hm, where kappa is a constant, which adds in quadrature to delta HPPG(0) to give the total Gaussian linewidth. Denoting the overall linewidth of the Voigt line in the absence of modulation broadening by delta HPP0(0), it is shown, both by analytical means and by spectral simulation, that the constant kappa is equal to 1/2 in the limit of Hm << = delta HPP0(0); however, using values of Hm as large as delta HPP0(0) leads to only minor departures from kappa = 1/2. The formulation is valid both for Lorentzian and Voigt lines and is tested for 2,2,5,5-tetramethylpyrrolidin-1-oxyl-3-carboxylic acid (3-carboxy proxyl) in CCl4 and in aqueous buffer. This spin probe was studied because the proxyl group is the only major spin-probe moiety whose Gaussian linewidth had not been characterized in the literature. For 3-carboxy proxyl, it is found that delta HPPG(0) = 1.04 +/- 0.01 G independent of solvent polarity. Precision values of the 14N hyperfine coupling constant for 3-carboxy proxyl at 9.5 degrees C are as follows: 14.128 +/- 0.001 G in CCl4 and 16.230 +/- 0.002 G in aqueous buffer. The temperature dependence of delta HPPG(0) and the 14N hyperfine coupling constant are reported as empirical equations. Results of the present work taken together with previously published data permits accurate correction for the effects of inhomogeneous broadening due to unresolved hyperfine structure and modulation broadening for the majority of spin probes in common use.

Ab Initio Study of the Electronic Spectrum of B2H2

The results of ab initio calculations of the potential curves for the torsional motion, symmetric H-B stretching, and B-B stretching in low-lying valence- and Rydberg-character triplet and singlet electronic states of B2H2 are reported. Particularly, the dissociation process B2H2 --> BH + BH out of various electronic states of B2H2 is studied. The nature of binding in B2H2 is discussed in terms of the composition of the electronic wavefunctions. Copyright 1997Academic Press

Ab Initio Study of the Electronic Spectrum of B2H2

The present paper represents the first part of an extensive theoretical study on the electronic spectrum of B2H2. The results of ab initio calculations of the vertical spectrum and the trans- and cis-bending potential curves for the low-lying triplet and singlet electronic states are reported. Special attention is paid to the study of the interaction between valence- and Rydberg-type electronic species. Copyright 1997Academic Press

In vivo spin-label murine pharmacodynamics using low-frequency electron paramagnetic resonance imaging

A novel, very-low-frequency electron paramagnetic resonance (EPR) technique is used to image the distribution of several nitroxides with distinct pharmacologic compartment affinities in the abdomens of living mice. Image acquisition is sufficiently rapid to allow a time sequence of the distribution for each compound. The spectra and concentrations of these nitroxides are imaged with the use of spectral-spatial imaging to distinguish a single spatial dimension. Liver and bladder of the mouse anatomy are distinguished by this technique. After an intraperitoneal injection of the spin-label probes, a shift in the distribution of the compounds from the upper abdomen (primarily liver) to the lower abdomen (primarily bladder) is observed. The time dependence of the shift in regional distribution depends on the structural properties of the side chain attached to the spin label. These results indicate that this application of in vivo electron paramagnetic resonance imaging will provide a new method of magnetic resonance imaging for determination of pharmacodynamics in the body of an intact animal.

Measurement of differences in pO2 in response to perfluorocarbon/carbogen in FSa and NFSa murine fibrosarcomas with low-frequency electron paramagnetic resonance oximetry

We have used very low-frequency electron paramagnetic resonance (EPR) oximetry to measure the change in oxygen concentration (delta pO2) due to change in breathing atmosphere in FSa and NFSa fibrosarcomas implanted in the legs of C3H mice infused with perfluoro-octylbromine (PFOB). Measurements in each tumor were made before and after the administration of the high-density (47% v/v) perfluorocarbon PFOB, perflubron (Alliance Pharmaceutical Corporation, San Diego, CA). Measurements in each tumor were also made, after the administration of the PFOB, both before (PFOB/air) and after the administration of carbogen (95% O2 + 5% CO2, PFOB/carbogen). Large changes (delta p02) relative to PFOB/air oxygenation were seen with the administration of PFOB/carbogen. No significant difference in oxygen concentration was seen between air-breathing mice with and without PFOB. The mean delta pO2 for FSa tumors was 13 +/- 6 torr, while the mean for NFSa fibrosarcomas was 28 +/- 7 torr. There were such large intertumor differences that the trend toward a smaller change in the more hypoxic FSa tumors was not significant (P = 0.13). This paper describes a novel method of measuring differences in oxygenation in tumor tissues. The results of such measurements indicate large differences in pO2 response to different breathing atmospheres in PFOB-infused tumors of similar histology. The intertumor delta pO2 differences may correlate with differences in radiation response.

"Kissing-balloon" technique for abdominal aorta angioplasty. Initial results and long term outcome

We evaluated results after angioplasty of the distal abdominal aorta using "kissing-balloon" technique. MATERIALS AND METHODS. From 1981 through 1993, 14 patients (12 women and 2 men, average age 52.4 years), underwent balloon angioplasty of the distal segment of the abdominal aorta. In 8 patients stenosis involved one or both iliac arteries as well. In all cases double balloon technique was used. Follow-up was based on clinical, angiographical and duplex scanning examinations. RESULTS. The initial success rate was 85% (12/14). In one case there was residual stenosis of 20% (redilated successfully 1 month later), and in one case there was acute thrombosis of the right iliac artery (successfully relieved surgically). Long-term follow-up (6-143 months) showed good patency of the dilated segment in all patients (including patients that initially failed). At follow-up, all patients were asymptomatic. CONCLUSION. Dilatation of the distal abdominal aorta using "kissing-balloon" technique is a safe and efficient modality of treatment, with acceptable initial and excellent long-term results.

Subaortic left ventricular pseudoaneurysm of obscure origin

Subaortic pseudoaneurysms of the left ventricle are rare acquired cardiac defects. They are usually associated with previous valve surgery, trauma, or aortic valve endocarditis. We describe the appearance of subaortic pseudoaneurysm 10 years after left heart catheterization in a patient with both aortic stenosis and regurgitation. The differential diagnosis of such lesions is presented.

In situ detection, by spin trapping, of hydroxyl radical markers produced from ionizing radiation in the tumor of a living mouse

Hydroxyl radicals are thought to be responsible for the toxicity associated with ionizing radiation in tissues. Measurements of hydroxyl radicals generated by ionizing radiation in cellular systems have failed thus far to elucidate higher-level homeostatic responses to this and other reactive oxygen species. Careful assessment of prior indirect hydroxyl radical assays in living tissues indicates that they are prone to a variety of artifacts, making all but the most qualitative relationships difficult to establish. This paper describes the detection of hydroxyl radicals produced during radiation in the leg tumor of a living mouse, where the free radicals evolve; detection uses low-frequency electron paramagnetic resonance in combination with in vivo spin trapping. To our knowledge, this is the first report of such a direct measurement of free radical production in the tissues of a living animals.

Oxymetry deep in tissues with low-frequency electron paramagnetic resonance

We have measured the oxygen concentration in the body water of murine FSa and NFSa fibrosarcomas using a new method for quantitative oxygen concentration determination deep in the tissues of a living animal. The measurement uses unusually low-frequency electron paramagnetic spectroscopy sensitive to substrate 7 cm deep in tissue, partially deuterated spin probes (spin labels of molecular mass 195, approximating that of glucose) whose distribution compartment can be targeted with facile adduct substitution, and novel analytic techniques. We show that the water-compartment oxygen concentration of the tumors decreases as the tumor size increases and also shows a trend to decrease as radiobiologic hypoxia increases. An oxymetric spectral image of the tumor is presented. The technique will improve with larger human tissue samples. It provides the potential to quantitatively assess tissue hypoxia in ischemic or preischemic states in stroke and myocardial infarction. It will allow direct assessment of tumor hypoxia to determine the usefulness of radiation and chemotherapy adjuvants directed to hypoxic cell compartments.

[Surgical treatment of diffuse coronary disease]

In order to obtain an idea on contemporary opportunities of surgical treatment of diffuse coronary disease the authors compared the results of surgery in 103 patients whose finding called for endarterectomy and bridging of at least one coronary artery (KEA) with the results in 220 patients where it was possible to overcome all significant changes by coronary bypasses only (KBP). Patients in group KEA had more infarctions before operation than patients in group KBP. Diffuse changes of the coronary arteries were found only in patients in group KEA. All patients were operated with extracorporeal circulation and local cooling of the myocardium. Surgery took longer in patients of group KEA than in group KBP. Early mortality was higher in group KEA--4.8% than in group KBP--0.9%. This difference was not statistically significant. Early morbidity in group KEA did not differ, from the morbidity in group KBP. Using effective peroperative protection of the myocardium by local cooling, the risk of KEA is only insignificantly higher than the risk of KBP. KEA makes safe and effective revascularization of the heart muscle in patients with diffuse coronary disease possible.

Use of a low-frequency ESR spectrometer: implications for spin-trapping free radicals, in situ

We have adapted the low-frequency ESR spectrometer, designed and built by H.J. Halpern, to the physiologic needs of organ preparations operating at 250 MHz. Initial studies have allowed us to detect nitroxides in an isolated perfused heart. These in situ measurements were made with nitroxides specifically designed to mimic the lipophilic nature of 5,5-dimethyl-1-pyrroline-1-oxide (DMPO) and 2,2-dimethyl-5-hydroxy-1-pyrrolidinyloxyl (DMPO-OH). These spin labels provided information about the influence of dynamic factors of the heart, such as flow rate, different cell populations and unequal distribution between compartments on our ability to conduct and interpret spin trapping experiments. They also clarified the sacrifice in sensitivity involved in operating at the lower frequencies. To deal with this later problem, we have increased the sensitivity of the spin trapping method by synthesizing a family of 15N- and deuterium-containing DMPO analogs and by determining their ability to spin trap free radicals generated by the model superoxide system of xanthine/xanthine oxidase. Finally, since activated neutrophils are one of the few cells known to generate free radicals as part of their physiologic function, we used these phagocytic cells, as a source of superoxide.

The treatment of advanced cardiac allograft rejection

Severe cardiac allograft rejection remains a serious problem despite the advances of cyclosporine-based immunosuppression. This study analyzes our experience with 202 recipients of cardiac allografts who were treated primarily with cyclosporine and prednisone. Failure of such therapy in 86 patients (43%) resulted in 105 episodes of advanced cardiac allograft rejection as diagnosed by endomyocardial biopsy. Of 101 rejection episodes that were initially treated with intravenous pulse therapy, 48 (48%) were successfully resolved, yet 60% of these successes were associated with major infections. Patients in whom steroid therapy failed or was contra-indicated received intravenous antithymocyte globulin (ATG) or intravenous monoclonal antibody (OKT3). ATG and OKT3 successfully reversed severe rejection in 26 (81%) of 32 and in 13 (93%) of 14 episodes, respectively. Infectious complication rates were 54% and 21%, respectively. Because the majority (87%) of these rejection episodes occurred within the first 30 days after treatment, many of them may have resulted from inadequate immunosuppressive induction therapy. Based on our results, we believe that advanced cardiac allograft rejection may be managed best by individualizing immunosuppressive therapy, thus enhancing prevention, and by adding OKT3 to the regimen when rejection occurs.

Cyclosporine A pharmacokinetics in a cardiac allograft recipient with a jejuno-ileal bypass

A 41-year-old man with a 13-year history of JI bypass for morbid obesity developed idiopathic cardiomyopathy. A pretransplant CsA pharmacokinetic profile demonstrated inadequate PO absorption with no appreciable enterohepatic recirculation. Inadequate levels occurred after three hours and became undetectable after 18 hours. The patient's status did not permit JI bypass reversal before transplantation. IV CsA was administered before cardiac transplantation, and a continuous IV CsA infusion was maintained for 72 days through episodes of CMV reactivation infection and complications common to the immunosuppressed patient. JI bypass reversal was subsequently performed and IV CsA converted to oral form as intestinal function improved. A repeat PO CsA pharmacokinetic profile demonstrated a threefold rise in peak concentration, delayed smaller peak concentrations representing enterohepatic recirculation, and a steady-state blood level that persisted for 23 hours. We have found that pretransplant CsA pharmacokinetic analysis predicts CsA bioavailability and serves as a guide for achieving optimal CsA serum concentrations; adequate PO absorption and enterohepatic recirculation of CsA depends on the anatomical and functional integrity of the jejunum and ileum; continuous IV CsA infusion can be precisely adjusted for optimal therapeutic efficiency; and long-term CsA infusion can benefit critically ill transplant patients without increased morbidity.

Orthotopic cardiac transplantation in patients with large donor/recipient atrial size mismatch: surgical technique

A successful surgical technique is described that overcomes the problem of severe size mismatch between the recipient's atrial remnants and the donor heart atria in patients undergoing orthotopic cardiac transplantation. The circumferences of the atria are reduced by plicating the atrial remnants until the appropriate sizes are obtained.