AAV-mediated delivery of interferon-β for the treatment of retinoblastoma in preclinical models

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Background: Interferon-β has anti-tumor properties against a variety of malignancies through direct cytotoxicity as well as immunological effects. In order to circumvent limitations of IFN-β therapy, we have developed an adeno-associated viral gene therapy approach to deliver IFN-β directly to tumors. In this study, we tested the efficacy of AAV mediated delivery of IFN-β in preclinical retinoblastoma models. Retinoblastoma is an ideal candidate for gene-therapy based anti-cancer treatments because viral infection and IFN-β delivery can be contained within the ocular environment thereby minimizing systemic toxicity. Methods: Retinoblastoma cell lines Weri and Y79 were treated in vitro with recombinant human Interferon-β and then subjected to Viacount assays, Nexin apoptosis assays, FACS cell cycle analysis, and immunolabeling for proliferation (BrdU) and apoptosis (caspase and TUNEL). An orthotopic Xenograft retinoblastoma rat model with luciferase reporter were established and treated with single subconjunctival injection of AAV-IFN-β gene therapy. Xenogen in vivo imaging was used to follow tumor volume. Blood and tissue samples (ELISA) were obtained to determine IFN-β levels. Results: Weri and Y79 cells showed maximum reduction in viability at 500 IU/ml and 2500 IU/ml respectively. Weri response was found to be cell death by Caspase and TUNEL assay. Y79 response was found to be due to suppression of proliferation as measured by BrdU incorporation and cell cycle analysis. In the retinoblastoma xenograft model there was no increase in tumor volume by serial in vivo imaging compared to control animals. Stable levels of IFN-β were maintained at 20 ng/ml >6weeks following injection. Plasma levels were undetectable 42 days following treatment. Conclusions: Retinoblastoma cell lines exhibit pleiotropic responses to IFN-β consistent with previous studies. Intravitreal injection of AAV-IFN-β resulted in efficient retinal infection and sustained IFN-β production. Viral spread outside of the eye was not detected. Using our retinoblastoma xenograft model we found that intravitreal injection of AAV-IFN-β had a potent anti-tumor effect in vivo. These data suggest that AAV mediated delivery of IFN-β may provide a complementary approach to systemic chemotherapy.

No significant financial relationships to disclose.

The inhibitor of apoptosis protein survivin is associated with high-risk behavior of neuroblastoma

BACKGROUND/PURPOSE

Apoptotic factors inducing or preventing cell death may intrinsically govern the behavior of some tumors. Survivin is a recently described member of the inhibitor of apoptosis protein (IAP) family, that is expressed in a cell cycle-dependent manner and is found in tumors of unfavorable histology. This study examines the presence of several apoptotic factors, including survivin, in neuroblastoma (NB) tumors. Clues to survivin's function in NB are provided by examining its association with behavior and cell dynamics in tumors and cell lines.

METHODS

Expression of a panel of apoptosis factors were quantified in 15 NB and related tumors before chemotherapy and in 3 NB cell lines (NB7, NB10, and NB16). Survivin and other apoptotic factors, as well N-myc amplification in primary tumors was correlated with recurrent disease and outcome. Proliferation rate, apoptosis assays, cell cycle analysis, and drug- or immune-mediated cell death were assessed in cell lines and evaluated in the context of differential survivin and apoptosis gene expression.

RESULTS

All 7 tumors that went on to recur expressed survivin, whereas expression was absent in all 8 tumors that went into remission. N-myc was amplified in 4 (57.1%) of the 7 recurrent tumors. Of the 8 tumors that were cured, Fas was expressed in 3 (38%), TRAIL-R1 in 6 (75%) and tumor necrosis factor (TNF)-R1 in 8 (100%), whereas these pro-apoptotic receptors were present in only 1 (14%), 1 (14%), and 4 (57%) of the 7 tumors that went on to recur, respectively. Of the 3 cell lines, NB10 expressed the least survivin, displayed the lowest proliferation index, and had the fewest number of cells in the G2/M (mitotic) phase of the cell cycle. Furthermore, NB10 also was most sensitive to TNF-related apoptosis-inducing ligand (TRAIL) or etoposide-induced cell death.

CONCLUSIONS

In primary NB tumors, survivin expression was associated with tumors of high risk and unfavorable prognosis, whereas pro-apoptotic receptor expression was more abundant in tumors of favorable prognosis. In this small series, survivin expression appeared to be more predictive of recurrent disease than N-myc amplification. In cell lines, survivin expression was cell cycle dependent, and its expression was associated with greater proliferation rates and greater resistance to drug- or immune-mediated cell death. Survivin expression may become a useful prognostic marker in NB and could be a potential target for the treatment of this tumor. J Pediatr Surg 36:1785-1791.

Factors influencing in vivo transduction by recombinant adeno-associated viral vectors expressing the human factor IX cDNA

Long-term expression of coagulation factor IX (FIX) has been observed in murine and canine models following administration of recombinant adeno-associated viral (rAAV) vectors into either the portal vein or muscle. These studies were designed to evaluate factors that influence rAAV-mediated FIX expression. Stable and persistent human FIX (hFIX) expression (> 22 weeks) was observed from 4 vectors after injection into the portal circulation of immunodeficient mice. The level of expression was dependent on promoter with the highest expression, 10% of physiologic levels, observed with a vector containing the cytomegalovirus (CMV) enhancer/beta-actin promoter complex (CAGG). The kinetics of expression after injection of vector particles into muscle, tail vein, or portal vein were similar with hFIX detectable at 2 weeks and reaching a plateau by 8 weeks. For a given dose, intraportal administration of rAAV CAGG-FIX resulted in a 1.5-fold or 4-fold higher level of hFIX compared to tail vein or intramuscular injections, respectively. Polymerase chain reaction analysis demonstrated predominant localization of the rAAV FIX genome in liver and spleen after tail vein injection with a higher proportion in liver after portal vein injection. Therapeutic levels of hFIX were detected in the majority of immunocompetent mice (21 of 22) following intravenous administration of rAAV vector without the development of anti-hFIX antibodies, but hFIX was not detected in 14 immunocompetent mice following intramuscular administration, irrespective of strain. Instead, neutralizing anti-hFIX antibodies were detected in all the mice. These observations may have important implications for hemophilia B gene therapy with rAAV vectors.

Accuracy of percutaneous lung biopsy for invasive pulmonary aspergillosis

BACKGROUND

Invasive pulmonary aspergillosis is fulminant and often fatal in immunosuppressed patients. Percutaneous biopsy may select patients who could benefit from surgical resection.

OBJECTIVE

We sought to determine the accuracy of percutaneous biopsy for pediatric invasive pulmonary aspergillosis.

MATERIALS AND METHODS

We retrospectively reviewed 28 imaging-guided percutaneous biopsies of the lungs of 24 children with suspected pulmonary aspergillosis. Twenty-two were being treated for malignancy and two for congenital immunodeficiency; 15 had received bone-marrow transplants. The accuracy of the percutaneous lung biopsy was determined by subsequent surgical resection, autopsy, or clinical course.

RESULTS

Histopathological studies showed ten biopsy specimens with septate hyphae, indicating a mold, and seven with Aspergillus flavus colonies in culture. The remaining 18 biopsies revealed no fungi. No patient had progressive aspergillosis after negative biopsy. Invasive pulmonary mold was detected by percutaneous biopsy with 100% (10/10) sensitivity and 100% (18/18) specificity. Percutaneous biopsy results influenced the surgical decision in 86% (24 of 28) of the cases. Bleeding complicated the biopsy in 46% (13/28) and hastened one death.

CONCLUSION

Percutaneous biopsy of the lung is an accurate technique for the diagnosis of invasive pulmonary aspergillosis and correctly determines which immunosuppressed pediatric patients would benefit from therapeutic pulmonary resection.

Hepatic iron concentration: noninvasive estimation by means of MR imaging techniques

PURPOSE

To identify a magnetic resonance (MR) imaging method sufficiently sensitive and specific in the estimation of hepatic iron content to obviate liver biopsy.

MATERIALS AND METHODS

Thirty-eight patients underwent percutaneous needle biopsy of the liver with chemical measurement of the hepatic iron concentration and hepatic MR imaging with several spin-echo and gradient-recalled-echo (GRE) techniques. Correlations between MR imaging parameters and the hepatic iron concentration were determined.

RESULTS

Inverse curvilinear relationships were noted between several MR parameters and hepatic iron concentrations. GRE sequences with short repetition and echo times were more accurate and precise than spin-echo sequences for the estimation of hepatic iron concentration. A GRE sequence with a repetition time of 18 msec, an echo time of 5 msec, and a flip angle of 10 degrees showed close correlation between the hepatic iron concentration and the natural logarithm of the ratio of the signal intensity of liver to the SD of background noise (r = -0.94) and low coefficient of variation (12%).

CONCLUSION

MR imaging with these parameters is a rapid, noninvasive, and accurate modality for estimation of hepatic iron concentration; it is sufficiently accurate and precise to obviate liver biopsy for the purpose of measuring hepatic iron concentration.

Control of monocyte influx in glomerulonephritis in transplanted kidneys in the rat

Induction of anti-Thy-1 nephritis in different strains of inbred rats results in phenotypically different types of renal diseases. In Wistar and Lewis (LEW) rats, a transient influx of ED1+ macrophages occurs 24 hours after injection of anti-Thy-1 antibodies, whereas this does not occur in F344 rats. The present experiments were designed to investigate the role of the kidney in the regulation of the monocyte influx in this model. To dissociate the role of the immune system from local intrarenal factors in the control of monocyte influx, anti-Thy-1 nephritis was induced in LEW rats with an F344 kidney transplant and in F344 rats with a LEW kidney allograft. Acute rejection episodes were prevented by treatment with an anti-CD4 monoclonal antibody. Control rats received a syngeneic kidney graft. Monocyte influx after injection of anti-Thy-1 antibodies was found in the glomeruli of both LEW and F344 kidneys removed from LEW recipients, whereas there was no demonstrable monocyte influx after infusion of anti-Thy-1 antibodies in either LEW or F344 kidneys removed from F344 recipients. Monocyte infiltration correlated with the subsequent expansion of the mesangial extracellular matrix. The inability to attract monocytes was not due to the lack of glomerular expression of chemokines, because F344 and LEW glomeruli demonstrated a similar expression of monocyte chemoattractant protein-1 (MCP-1). Differences in the ability to activate the complement system were excluded. We conclude that the immune system controls the glomerular influx of monocytes and that the reaction of the mesangial cells is probably controlled by combinations of cytokines produced during the inflammatory process.

Neonatal sternal cleft associated with an extrathoracic cystic mass

This report describes an unusual case of cystic exophytic tumor associated with a complete sternal cleft. The tumor masked the presence of sternal cleft on prenatal ultrasound scan.

Antihypertensive drug treatment in chronic renal allograft rejection in the rat. Effect on structure and function

To gain insight into the contribution of immunologic and hemodynamic factors in the progressive demise of structure and function in chronic renal allograft dysfunction, we studied the histological changes, the immunostainable glomerular anionic sites, and glomerular capillary hydrostatic pressures of rat renal allografts with chronic rejection. Recipient animals were left untreated, received 8 weeks of treatment with the immunosuppressive drug cyclosporine, or received antihypertensive drugs consisting of the combination of reserpine, hydralazine and hydrochlorothiazide, the angiotensin-converting enzyme inhibitor cilazapril, or the angiotensin II receptor blocker L-158,809. Grafts in untreated recipients developed chronic interstitial inflammation, as well as vascular and glomerular lesions consistent with chronic rejection. These lesions were associated with immunohistochemical loss of the negatively charged heparan sulfate proteoglycan side chain. All treatment regimens decreased the systemic and glomerular capillary pressures and were associated with no loss of function, decreased proteinuria, and a tendency to improved graft function. Cyclosporine prevented all histological manifestations of rejection, and antihypertensive drugs decreased the extent of glomerular mesangiolysis and glomerulosclerosis; L-158,809 and cilazapril also inhibited graft atherosclerosis and tubular atrophy. We conclude that chronic rejection is primarily an immune-mediated process, but hemodynamic and angiotensin II-mediated effects may play a pivotal role in the expression of immune-mediated lesions.

Growth factor transcripts in rat renal transplants

Locally produced cytokines and growth factors may mediate tissue remodelling processes, as observed in renal transplants exposed to ischemia or acute rejection episodes. The present study was designed to investigate mRNA transcript levels of platelet-derived growth factor (PDGF)-receptor beta, PDGF-A, PDGF-B, fibroblast growth factor-1, and transforming growth factor beta 1 in normal rat kidneys, in kidneys following contralateral nephrectomy and in renal transplants with acute or chronic rejection. Platelet-derived growth factor-receptor beta mRNA levels increased significantly in syngeneic and allogeneic transplants in the first week after transplantation and in allogeneic transplants with chronic rejection. Immunohistochemistry showed induction of PDGF-receptor beta protein expression on vascular wall cells in such grafts. Platelet-derived growth factor-A chain mRNA levels increased in day 3 allografts and in syngeneic LEW grafts, while PDGF-B chain mRNA levels showed no significant changes with transplantation. Fibroblast growth factor-1 mRNA levels were detectable in normal kidneys, tended to decrease with acute rejection, and increased significantly in chronic rejection. Transforming growth factor-beta 1 transcripts increased in acute and chronic rejection; immunohistochemistry showed predominantly glomerular localization of the transforming growth factor-beta 1 protein. We conclude that transplantation and rejection are associated with changes in the intragraft mRNA levels for several growth factors; chronic rejection is characterized by an increase in fibroblast growth factor-1 and transforming growth factor-beta 1 transcript levels.

Anti-integrin (LFA-1, VLA-4, and Mac-1) antibody treatment and acute cardiac graft rejection in the rat

Cell adhesion molecules mediate interactions with other cells and extracellular matrix, control cell infiltration in sites of inflammation, and regulate cell activation. Previous studies have shown that treatment of rat cardiac transplant recipients with a combination of antibodies against the T-cell integrins LFA-1 and VLA-4 gave a modest prolongation of graft survival. Current experiments were designed to examine the effect of blocking Mac-1, an important monocyte adhesion receptor and mediator of monocyte migration, together with anti-LFA-1 and anti-VLA-4 antibodies on cardiac graft survival and on the graft rejection pattern. The anti-Mac-1, CD11b-specific antibody OX-42 did not affect graft survival time although it did decrease the graft infiltration by rounded, ED-2-positive macrophages.

Orthotopic liver transplantation for inflammatory myofibroblastic tumor of the liver hilum

Inflammatory myofibroblastic tumor is a rare gastrointestinal neoplasm. The authors report the case of a 5-year-old girl who initially presented with gastric outlet obstruction secondary to an inflammatory myofibroblastic tumor along the lesser gastric curvature. A subtotal gastrectomy and wedge resection of a left hepatic lobe nodule were performed. Obstructive jaundice developed one month postoperatively. Computerized tomography, percutaneous transhepatic cholangiography, and selective celiac and mesenteric arteriography showed a mass that involved the left hepatic lobe, with concomitant high-grade biliary obstruction and portal venous encasement. Percutaneous biliary drainage was performed. During laparotomy, the tumor was found to be unresectable, and the patient was referred to the Liver Transplant Service at The Children's Hospital of Philadelphia. A total hepatectomy with temporary portocaval shunt was performed, leaving the inferior vena cava in situ. At the back table, an ex vivo left trisegmentectomy was performed, followed by reimplantation of the posterior segment of the right hepatic lobe. The reimplanted liver segment functioned poorly, and completion hepatectomy with portocaval shunt was performed 24 hours postoperatively, because of severe coagulopathy, intraabdominal bleeding, and hemodynamic instability. The patient's condition stabilized, and she was listed for urgent liver transplantation. The anhepatic state was managed with intermittent plasmapheresis. She had transplantation 72 hours later, and was discharged from the hospital 3 weeks postoperatively after an uneventful recovery. She remains disease-free and has normal liver function 8 months after transplantation.

Successful management of intracardiac extension of tumor thrombus in a patient with advanced nonseminomatous germ cell testicular cancer

A young patient with testicular germ cell tumor presenting with inferior vena cava thrombus extending into the right heart with free-floating thrombus in the right ventricle and a simultaneous epidural spinal cord compression is presented. Due to the perceived high risk of embolization and the urgent need to begin systemic chemotherapy, he was managed with tumor thrombectomy utilizing cardiopulmonary bypass and hypothermic circulatory arrest followed shortly thereafter by systemic chemotherapy. There were no perioperative complications, and he is alive and without recurrence 24 months following four cycles of systemic chemotherapy.

Cardiac allograft atherosclerosis in the rat. The effect of histocompatibility factors, cyclosporine, and an angiotensin-converting enzyme inhibitor

Cardiac transplant atherosclerosis is thought to result from immune-mediated vessel wall injury. The present experiments were designed to test whether CsA alone or in combination with the ACE-inhibitor cilazapril has any effect on graft atherosclerosis in a rat cardiac transplant model. Cardiac grafts were transplanted heterotopically into either syngeneic or allogeneic recipients and followed by daily palpation; long-surviving grafts were removed after 100 days and the extent and degree of atherosclerosis was assessed using computerized morphometry. Atherosclerosis was more extensive in grafts removed from untreated allogeneic recipients compared with syngeneic recipients; CsA treatment increased the extent of atherosclerosis in syngeneic transplants. The extent and degree of vascular occlusion in allogeneic grafts from recipients treated with 15 mg/kg of CsA every other day was not different from that in grafts removed from recipients that received initially higher CsA doses. Cilazapril had no effect on the extent of graft atherosclerosis but decreased the degree of luminal narrowing in grafts from CsA-treated recipients significantly. Some grafts showed neovascularization in the subendocardial region adjacent to organized intraventricular clots, suggesting the release of angiogenic factors from such clots; such growth factors may contribute to the atherosclerotic vessel wall reaction in this model. We conclude that CsA promotes the development of graft atherosclerosis in heterotopically transplanted syngeneic cardiac grafts in the rat. We furthermore found that cilazapril has a beneficial effect on the degree of atherosclerosis in CsA-treated recipients.

Contrast-enhanced MR imaging of the liver

Postcontrast images with a 0.1 mmol/kg dose of a gadolinium chelate with extracellular distribution, when acquired dynamically during breath holding, can improve both differential diagnosis and lesion recognition in liver MR imaging. Initial results at 0.3 mmol/kg, compared with 0.1 mmol/kg, suggest a substantial improvement in lesion identification at the high dose, as assessed by using signal intensity difference divided by noise. Of the gadolinium chelates with predominantly renal excretion, only gadoteridol is presently approved in the United States at the high dose, with limited clinical evaluation for liver imaging performed to date. For linear chelates, such as gadopentetate dimeglumine and gadodiamide injection, the degree to which release of free gadolinium ion occurs is a possible issue because of lower in vivo stability (42,43). Preliminary results with hepatobiliary gadolinium chelates and iron particulate agents are favorable with regard to efficacy, although these agents remain in clinical trials.

Maternal umbilicus: ultrasound window to the gravid uterus

Transabdominal sonograms of 68 consecutive pregnant women were reviewed retrospectively. Images of fetal parts obtained through the umbilical window (UW) were compared with those obtained through the paraumbilical window (PUW) as to (1) thickness of tissue to amniotic cavity, (2) clarity of the part imaged, and (3) noise produced. The paraumbilical tissue thickness had a mean of 18 mm; the umbilical tissue thickness, a mean of 11 mm. In patients where the difference in thickness of their paraumbilical tissue and umbilical tissue was only 0 mm to 6 mm (group 1), the UW improved clarity in 10 of 34 (29%), reduced clarity in 3 of 34 (9%), and did not change clarity in 21 of 34 (62%). Improvement of images with use of the UW was not statistically significant. However, in the group of patients with the difference in tissue thickness between the paraumbilical and umbilical areas of > 6 mm (group 2), clarity was improved in 19 of 32 (60%), reduced in 2 of 32 (6%), and was unaltered in 11 of 32 (34%). In this group the image improvement with the UW was statistically significant. Images through the UW had relatively less noise. In group 1, noise was reduced in 12 of 35 (34%). The effect of the UW on noise reduction was more significant in group 2 (tissue thickness difference > 6 mm): 24 of 31 (77%) of cases.

Chronic renal allograft rejection in the rat. Transplantation-induced antibodies against basement membrane antigens

BACKGROUND

To obtain understanding of the immunologic mechanism of chronic rejection-associated glomerular and interstitial renal damage, we investigated the humoral immune response against donor type glomerular and tubular basement membrane proteins in rats with long-surviving renal transplants with and without chronic rejection.

EXPERIMENTAL DESIGN

Sera from Lewis and Fisher 344 rats with long-surviving Fisher 344 and Lewis renal allografts were investigated by enzyme-linked immunosorbent assay and Western blot analysis using collagenase-digested renal basement membrane preparations from various strains of rats.

RESULTS

Kidneys from F344 strain donors transplanted into Lewis recipients developed glomerular lesions consistent with transplant glomerulopathy as well as chronic tubulointerstitial inflammation and fibrosis. Indirect immunofluorescence studies of the Lewis anti-Fisher 344 post-transplant sera showed the presence of antibodies that gave punctate staining in the glomeruli and bright, linear staining of the proximal tubular basement membrane. Dot blot analysis of the sera showed the presence of antibodies against Fisher and third party Brown Norway glomerular basement membranes, whereas no reactivity was found with recipient strain basement membranes. Western blot analysis with glomerular basement membrane preparations showed that the antibodies recognized several antigens under nonreducing (> 200 and approximately 100 kilodaltons) and reducing (> or = 200, approximately 200, approximately 90, approximately 50 to 60, and < 45 kilodaltons) conditions. Western blots with tubular basement membrane proteins showed antibodies against various antigens. Anti-basement membrane antibodies were not found after conventional immunizations with kidney homogenates or after transplantation of cardiac allografts. Fisher 344 rats with long-surviving Lewis renal transplants produced antibodies against laminin fragments, but these antibodies were not associated with transplant glomerulopathy.

CONCLUSIONS

We found that Lewis rats that carry a Fisher 344 renal allograft with transplant glomerulopathy produce antibodies against one or more novel antigen(s) of donor glomerular and tubular basement membranes. The role of these antibodies in the pathogenesis of transplant glomerulopathy and chronic rejection-associated tubulointerstitial inflammation remains to be established.

Glomerular capillary pressures in long-surviving rat renal allografts

Many renal transplants undergo gradual deterioration in structure and function in the months or years after transplantation. The processes that underlie this progressive decline have not been defined, and may include immunological and nonimmunological mechanisms. The present experiments were designed to investigate the glomerular capillary hydrostatic pressure in long-surviving rat renal transplants with or without chronic rejection. Stop-flow glomerular pressures were measured in F344 renal allografts with chronic rejection, syngeneic F344 grafts, and long-surviving syngeneic and allogeneic LEW grafts without chronic rejection; control measurements were done in nontransplanted intact animals or after subtotal renal ablation. Renal ablation or transplantation resulted in increased glomerular pressure in F344 but not LEW kidneys; the glomerular pressure in syngeneic F344 grafts was not different from that in allogeneic F344 grafts. There was no correlation between the mean arterial pressure and the glomerular capillary pressure. Our data suggest that the glomerular capillary pressure is determined by local intrarenal factors. The glomerular capillary pressure in allotransplanted kidneys resembles that of the donor kidney after subtotal renal ablation. The importance of increased glomerular pressure in the progressive decline of graft function of chronic rejection remains to be established.

Management of major biliary complications after laparoscopic cholecystectomy

OBJECTIVE

A total of 50 major bile duct injuries after laparoscopic cholecystectomy were managed by the Duke University Hepatobiliary Service from 1990-1992. The management of these complex cases is reviewed.

SUMMARY BACKGROUND DATA

Laparoscopic cholecystectomy is the preferred method for removing the gallbladder. Bile duct injury is the most feared complication of the new procedure.

METHODS

Review of videotapes, pathology, and management of the original operations were reviewed retrospectively, and the injuries categorized. Major biliary injury was defined as a recognized disruption of any part of the major extrahepatic biliary system. Biliary leakage was defined as a clinically significant biliary fistula in the absence of major biliary injury, i.e., with an intact extrahepatic biliary system.

RESULTS

Thirty-eight injuries were major biliary ductal injuries and 12 patients had simple biliary leakage. Twenty-four patients had the classic type injury or some variant of the classic injury. A standard treatment approach was developed which consisted of ERCP for diagnosis, preoperative PTC with the placement of stents, CT drainage immediately after the PTC for drainage of biliary ascites, and usually Roux-en-Y hepaticojejunostomy with placement of O-rings for future biliary access if necessary. Major ductal injuries were high in the biliary system involving multiple ducts in 31 of the 38 patients. Re-operation was required in 5 of the 38 patients with particularly complex problems.

CONCLUSIONS

Successful management of bile duct injury after laparoscopic cholecystectomy requires careful understanding of the mechanisms, considerable preoperative assessment by experts, and a multidisciplinary approach.

Budd-Chiari syndrome in autosomal dominant polycystic kidney disease: a complication of nephrectomy in patients with liver cysts

We report two patients with autosomal dominant polycystic kidney disease (ADPKD) who developed the Budd-Chiari syndrome following bilateral nephrectomy. Both patients had massive cystic enlargement of the liver. Neither had any other identifiable risk factors for the Budd-Chiari syndrome. We suggest that removal of the kidneys may predispose toward anatomic obstruction of the inferior vena cava or hepatic veins by liver cysts. Nephrectomy should be approached cautiously in ADPKD patients with extensive involvement of the liver by cysts.

The effect of interferon gamma on epidermal growth factor receptor expression in normal and malignant ovarian epithelial cells

OBJECTIVE

We examined the effect of interferon gamma on proliferation and epidermal growth factor receptor expression in ovarian cancer cell lines and normal ovarian epithelial cells.

STUDY DESIGN

The tritiated thymidine incorporation assay was used to assess the effect of interferon gamma on proliferation. Scatchard analysis of anti-epidermal growth factor receptor antibody binding, and Western blotting of immunoprecipitates was used to assess the effect of interferon gamma on epidermal growth factor receptor expression.

RESULTS

Although interferon gamma elicited 30% to 40% decreases in proliferation, epidermal growth factor receptor expression was strikingly increased in all four ovarian cancer cell lines. Scatchard analysis indicated that this increase occurred primarily at the cell surface, but total cellular receptor levels also were increased. In contrast, interferon gamma treatment of normal ovarian epithelial cells affected neither proliferation nor epidermal growth factor receptor levels.

CONCLUSION

Because the up-regulation of epidermal growth factor receptors by interferon gamma appears to be confined to malignant cells, interferon gamma may facilitate immunotherapy and imaging of ovarian cancers by means of immunoconjugates directed against the epidermal growth factor receptor.

Left ventricular mass quantitation using single-phase cardiac magnetic resonance imaging

Magnetic resonance imaging (MRI) has been used to measure left ventricular (LV) mass in animals with superior accuracy. However, its use in cardiac patients has been limited by the long total scan times necessitated by imaging the heart at end-diastole at each of 8 to 10 slice locations. Recent canine studies showed that LV mass may be determined accurately, with considerable timesavings, by use of sequential images throughout the cardiac cycle (single-phase MRI). Twenty normal subjects underwent spin-echo MRI to determine the relationship between LV mass computed from single-phase MRI and results obtained from the more time-consuming end-diastolic MRI (which was used as the reference standard for this study). The left ventricle was spanned with 2 interleaved series of 5 short-axis 1 cm thick slices. 5 images, evenly spaced throughout the cardiac cycle, were obtained at each slice location in all subjects. LV mass ranged from 86 to 198 g. Although end-diastolic LV mass exceeded single-phase results by an average of 5 g (p less than 0.002), there was a close correlation between the 2 (slope = 0.99; r = 0.96). Although LV mass derived from end-diastolic images exceeded single-phase results, this difference is unlikely to be clinically significant and is small compared with the standard error of echocardiographic methods. Furthermore, when the order in which single-phase images were selected was reversed, there was improved agreement with end-diastolic MRI.(ABSTRACT TRUNCATED AT 250 WORDS)

Traumatic aortic tear: screening with chest CT

Dynamic chest computed tomography (CT) was performed in 326 patients who had undergone abdominal CT for blunt trauma to evaluate the role of chest CT in screening for thoracic aortic injury. Evidence of mediastinal bleeding constituted an abnormal CT examination. The results were correlated with those from aortography in 131 patients. The chest radiographs were abnormal in 127 patients (39%). Of those 127 patients, chest CT scans were abnormal in 39 patients; an aortic tear was present in eight of those patients (21%). The remaining 88 patients had normal CT scans and no aortic injury. Of the 199 patients with normal radiographs, 15 had abnormal CT scans and 184 had normal CT scans and no aortic injury. There were no false-negative CT scans; 79% of patients with normal CT scans had false-positive chest radiographs. With CT there was a significant improvement over plain radiography in specificity, accuracy, and predictive value of positive results. If chest CT were used as an adjunct to chest radiography in the screening for traumatic aortic tear, the need for aortography would decrease by 56%. Chest CT can safely help discriminate candidates for aortography, is cost-effective, and, in hemodynamically stable patients, should be incorporated in the screening for traumatic aortic tear.

Macrophage subpopulations in normal and transplanted heart and kidney tissues in the rat

The purpose of the present study was to investigate the phenotype of macrophages that infiltrate normal and transplanted rat tissues. The macrophage monoclonal antibodies ED1, ED2, ED3, 52-1D4, ER15, and OX43, together with antibodies against lymphocyte and class II MHC antigens, were used in an indirect immunofluorescence technique with sections of normal tissues and heart and renal grafts that experienced long-term survival or rejection. A small number of ED1- and ED3-positive interstitial cells were detected in normal heart and renal tissues and their number increased dramatically in rejection. Normal heart tissue contained a population of ED2-positive cells with dendritic morphology that was not detected in renal tissue. Following transplantation, a diffuse increase of rounded ED2-positive cells was observed in heart grafts; no ED2-positive cells were detected in grafts removed after 20-30 days from nonimmunosuppressed recipients. Grafts from CsA-treated animals or grafts that survived greater than 50 days in nonimmunosuppressed recipients exhibited the interstitial dendritic pattern of ED2-positive cells. Only very few rounded ED2-positive cells were observed in renal allografts; if present, they were mostly located in the medulla. OX43, which bound in normal tissues to vessel endothelium and a population of macrophages, stained in allografts an additional small population of graft-infiltrating cells, and in F344 renal allografts a population of multinucleated giant cells. We conclude that the posttransplant macrophage infiltration pattern of heart and renal allografts, defined by the monocyte/macrophage antibodies ED1, ED3, 52-1D4, and ER15, is very similar for both types of organs, although the antibody ED2 and the endothelial-macrophage antibody OX43 revealed remarkable differences between the two types of organ allografts.

Magnetic resonance imaging of an infected urethral diverticulum: a case report

We present a case report of a urethral diverticulum where magnetic resonance imaging suggested infected contents of the urethral diverticulum besides providing superb detail of periurethral anatomy. The critical clinical question was answered.

The value of non-contrast-enhanced CT in blunt abdominal trauma

The usefulness of non-contrast CT, limited to the upper abdomen, in conjunction with conventional IV contrast-enhanced scanning was studied prospectively in 190 patients who had sustained blunt abdominal trauma. In 78, visceral injuries were confirmed at surgery or at follow-up CT. Of the patients with injuries, 14 (18%) had hyperdense hematomas on the non-contrast studies that became isodense after IV administration of contrast material. These hematomas generally were small and posed an immediate threat to life in only one patient (0.5% of all subjects). In 13% of patients with injury (5% of the total), the additional information did influence treatment planning (surgery in two and intensive conservative treatment in eight). Compared with conventional contrast scanning, the combined non-contrast-contrast technique increased the scanning time only by about 5 1/2 min, but it improved the sensitivity and accuracy of CT in detecting visceral injuries from 74% and 84% to 92% and 91%, respectively (p less than or equal to .003 and p less than or equal to .04). Although contrast-enhanced scanning alone accurately depicts visceral injuries requiring surgical treatment, the incorporation of a non-contrast sequence can detect a subgroup of patients who require intensive conservative management with bed rest and close observation. This additional information can be obtained expeditiously, with minimal additional effort or intervention. The use of non-contrast scanning alone is not recommended.

Nonoperative treatment of adult splenic trauma: development of a computed tomographic scoring system that detects appropriate candidates for expectant management

We reviewed the charts of 87 patients with documented splenic injuries resulting from blunt trauma admitted to a regional trauma referral center during the 32-month period beginning in January 1984. Delayed celiotomy was defined as surgical intervention for splenic injury after a trail of nonoperative management lasting at least 24 hours. Delayed celiotomy was not required in any of the 16 cases in the pediatric age group (age less than or equal to 17 years) who were initially managed nonoperatively. In contrast, of the 27 adults who were initially treated nonoperatively, ten (37%) ultimately required celiotomy. Although splenorrhaphy was successfully performed in 21 of 44 patients undergoing early operation, all ten of the patients requiring celiotomy after an unsuccessful trial of observation underwent splenectomy rather than a spleen-preserving procedure. Of the 27 adults who were initially managed nonoperatively, 24 had abdominal computed tomography (CT) performed during their initial diagnostic evaluation. Twenty-three of these scans were reviewed by one of the authors. A CT scoring system was developed, based on the degree of splenic parenchymal and capsular injury and the amount of fluid in the abdomen and the pelvis. Adult patients who were successfully treated without operation had a significantly (p = 0.011) lower total CT score than did patients who required delayed celiotomy. No adult with a total CT score less than 2.5 required delayed operative intervention. These data support

CT of the pancreas with a fat-density oral contrast regimen

Visualization of the head of the pancreas by CT was prospectively evaluated in two groups of 100 patients who did not have pancreatic disease. Patients were given either a fat-density oral contrast material (12.5% corn-oil emulsion and metoclopramide) or a conventional high-density oral contrast material (barium suspension or iodinated solution). There was no statistically significant difference in the subjects' tolerance to the two regimens. There was, however, a significant improvement in ability to distinguish the head of the pancreas from the duodenal C-loop when the fat-density contrast material was given. When pancreaticoduodenal discrimination was graded, patients given corn-oil emulsion and metoclopramide received an average score of 0.94, whereas those given the high-density agent received an average score of 0.74, with 1.00 being the highest possible score (p less than .005). These data suggest that for routine CT evaluation of the head of the pancreas, a combination of corn-oil emulsion and metoclopramide may be superior to the conventional high-density oral contrast agents given without metoclopramide.

The normal diameter of the fetal aorta and pulmonary artery: echocardiographic evaluation in utero

Measurements of the fetal aorta and pulmonary artery can aid in the detection and diagnosis of congenital heart defects. In a prospective study of 403 normal fetuses whose gestational ages were between 14 and 42 weeks, two-dimensional (2D) real-time and M-mode echocardiography were used to measure the diameters of the aortic root and the pulmonary artery in utero. The goals were to establish norms for the diameters of these structures as a function of both gestational age and biparietal diameter, to compare measurements obtained in systole and diastole, and to compare 2D and M-mode measurements. A high correlation was found between measurements made during systole and diastole (r = .994 for aorta, r = .996 for pulmonary artery) and between 2D and M-mode measurements for each vessel (r = .992 for aorta, r = .973 for pulmonary artery). The differences between systolic and diastolic measurements and between M-mode and 2D measurements were small (2.2-4.6%) for both the aorta and the pulmonary artery. The norms established here provide an objective standard for comparison when a cardiac anomaly involving a fetal aorta or pulmonary artery of abnormal size is suspected. The results indicate that a sonographic facility need not have M-mode equipment to obtain technically adequate measurements.

Fat-density oral contrast agent for abdominal CT

To overcome the problem of inadequate mixing of gastrointestinal (GI) tract contents with conventional high-density oral contrast agents in abdominal computed tomography (CT), a flavored 12.5% corn oil emulsion (COE) was tested as an oral contrast agent in 62 patients. The results were compared with those obtained from 105 patients who received high-density oral contrast agents. A simple patient preparation regimen for the COE was developed, which appears to be reasonably well tolerated by the patients and yields diagnostic studies comparable to those obtained with conventional agents. Use of the COE resulted in consistent discrimination of the GI tract and depiction of the GI wall. Preliminary data suggest that it may be particularly useful for CT evaluation of the stomach, duodenum, and pancreas; in patients suspected of having solid tumors; and in thin people.