A phase II trial of isotretinoin and alpha interferon in patients with recurrent squamous cell carcinoma of the cervix: a Gynecologic Oncology Group study

From January 1993 through January 1996, 37 patients with unresectable squamous carcinoma of the cervix were entered on study and scheduled to receive oral isotretinoin 1 mg/kg per day with subcutaneous alpha interferon 6,000,000 units/day. A course was defined as 4 continuous weeks of therapy. The mean number of four-course cycles delivered was 1.8. One patient was ineligible because of wrong cell type and two were never treated. Thus, 34 patients were evaluable for toxicity. Eight patients were inevaluable for response. Five did not receive a complete 4-week course and three did not have additional tumor measurements; thus 26 were evaluable for response. Prior radiotherapy had been given to 25 patients and prior chemotherapy to 23 patients. There was no grade 4 neutropenia. The incidence of Gynecologic Oncology Group (GOG) grade 3 granulocytopenia and thrombocytopenia was 8.8% and 5.8%, respectively. Six patients (17.6%) developed grade 3 or worse nausea and vomiting. Four (11.7%) patients developed grade 3 neurologic symptoms. There were no complete responses and one partial response. The overall response rate was 3.8% (95% confidence interval, 0.1-19.6%). In this pretreated population, isotretinoin and alpha interferon in the dose and schedule employed exhibit minimal activity.

Spinal cord neural anatomy in rats examined by in vivo magnetic resonance microscopy

BACKGROUND AND OBJECTIVES

Magnetic resonance microscopy (MRM) is a technique that is worthwhile for anesthesiologists because it allows spinal cord and plexus anatomy to be visualized three dimensionally and followed over time in the same animal. For example, the long-term effect of indwelling intrathecal or plexus catheters can be studied in situ, and convective and diffusive forces within intrathecal, epidural, or nerve sheath spaces can be investigated. Further, diffusion-weighted MRM, which measures an "apparent diffusion coefficient" (ADC), can be used to track the presence of ischemia, hypoperfusion, or cytotoxic edema. This study investigates problems associated with the use of in vivo MRM for spinal cord and peripheral nerve studies in the rat.

METHODS

Twenty-one anesthetized female Fisher CDF rats were used. Group 1 (n=7) was used for anatomic three-dimensional studies. Groups 2 (n=4), 3 (n=4), and 4 (n=6) were used for measurements of the ADC. Group 2 served as controls, group 3 received lumbar intrathecal catheters, and group 4 received cervical intrathecal catheters.

RESULTS

Cervical spine, lumbar spine, and spinal nerves and ganglia were accurately visualized with MRM. As a rule, spinal cord gray and white matter were better demonstrated using diffusion-weighted proton stains. By contrast, T2-weighted proton staining superiorly demonstrated structures surrounding the spinal cord. In groups 3 and 4, indwelling intrathecal catheters did not affect the spinal cord ADC, indicating normal blood flow and no cytotoxic edema. Contrast studies revealed nonhomogeneous distribution of contrast predominately in the lateral and ventral intrathecal space.

CONCLUSION

Three-dimensional diffusion-weighted MRM displays cervical and lumbar spine anatomy accurately in vivo. Apparent diffusion coefficients measurements are feasible in rat cervical spinal cord with intrathecal catheters. Spinal cord ADCs are unaffected by intrathecal catheters, indicating normal spinal cord perfusion.

Signal dynamics in magnetic resonance imaging of the lung with hyperpolarized noble gases

The nonequilibrium bulk magnetic moment of hyperpolarized (HP) noble gases generated by optical pumping has unique characteristics. Based on the Bloch equations, a model was developed describing the signal dynamics of HP gases used in magnetic resonance imaging (MRI) of the lung with special consideration to the breathing cycle. Experimental verification included extensive investigations with HP 3He and 129Xe during both inspiration and held breath in live guinea pigs. Radial acquisition was used to investigate the view variations with a temporal resolution of 5 ms. Agreement between theoretical predictions and in vivo results was excellent. Additionally, information about effects from noble gas diffusion and spin-lattice relaxation was obtained. In vivo results for T1 were 28.8 +/- 1.8 s for 3He and 31.3 +/- 1.8 s for 129Xe. Comparison with in vitro data indicated that relaxation in the pulmonary gas space is dominated by dipolar coupling with molecular oxygen. The results provide a quantitative basis for optimizing pulse sequence design in HP gas MRI of the lung.

AB-180 circulatory support system: summary of development and phase I clinical trial

The AB-180 Circulatory Support System (AB-180 CSS; Cardiac Assist Technologies, Pittsburgh, PA) is a left ventricular assist system for investigational use in patients with postcardiotomy cardiogenic shock who are refractory to standard treatment with an intra-aortic balloon pump, pharmacologic treatment, or both. The intent of the AB-180 CSS is to provide temporary (up to 14 days) mechanical circulatory support until the heart recovers adequate mechanical function. The system consists of a small implantable centrifugal pump and a controller. A unique infusion system produces a hydrodynamic bearing between rotational and stationary components of the AB-180 CSS pump. This infusion system also provides a source of heparin for localized anticoagulation. Extensive bench and animal work has illustrated anticoagulation requirements, established operating guidelines, and demonstrated safety and efficacy. An investigational device exemption has been granted for a Phase I, five patient feasibility study at Allegheny General Hospital in Pittsburgh, Pennsylvania. To date, the pump has been implanted in one patient. The results from this first case are presented here.

In vivo magnetic resonance vascular imaging using laser-polarized 3He microbubbles

Laser-polarized gases (3He and 129Xe) are currently being used in magnetic resonance imaging as strong signal sources that can be safely introduced into the lung. Recently, researchers have been investigating other tissues using 129Xe. These studies use xenon dissolved in a carrier such as lipid vesicles or blood. Since helium is much less soluble than xenon in these materials, 3He has been used exclusively for imaging air spaces. However, considering that the signal of 3He is more than 10 times greater than that of 129Xe for presently attainable polarization levels, this work has focused on generating a method to introduce 3He into the vascular system. We addressed the low solubility issue by producing suspensions of 3He microbubbles. Here, we provide the first vascular images obtained with laser-polarized 3He. The potential increase in signal and absence of background should allow this technique to produce high-resolution angiographic images. In addition, quantitative measurements of blood flow velocity and tissue perfusion will be feasible.

Stochastic resonance in coupled nonlinear dynamic elements

We investigate the response of a linear chain of diffusively coupled diode resonators under the influence of thermal noise. We also examine the connection between spatiotemporal stochastic resonance and the presence of kink-antikink pairs in the array. The interplay of nucleation rates and kink speeds is briefly addressed. The experimental results are supplemented with simulations on a coupled map lattice. We furthermore present analytical results for the synchronization and signal processing properties of a Phi(4) field theory and explore the effects of various forms of nonlinear coupling. (c) 1998 American Institute of Physics.

Complex induction of bovine uterine proteins by interferon-tau

Interferon-tau (IFN-tau) is released by the conceptus and induces two uterine proteins during early pregnancy: ubiquitin cross-reactive protein (UCRP) and granulocyte chemotactic protein-2 (GCP-2). The present experiments were designed to determine whether detection (Western blot) of cytosolic UCRP and release of GCP-2 could be used to examine IFN-tau signal transduction in cultured endometrial explants and primary epithelial cells. Recombinant (r) type 1 IFNs (rboIFN-tau and rboIFN-alpha; 5, 25, 100 nM) induced UCRP, but only rboIFN-tau induced GCP-2 in explant culture. Recombinant boIFN-tau and conceptus secretory proteins containing native IFN-tau induced UCRP and GCP-2 in cultured primary epithelial cells. All concentrations of rboIFN-alpha (25, 50, 100 nM) induced UCRP, but only the highest concentration induced GCP-2 in cultured primary epithelial cells. Interestingly, phorbol ester (100, 500, 1000 ng/ml) induced GCP-2, but it had no effect on UCRP. Because type 1 IFNs induce UCRP, IFN-tau probably interacts with the janus kinase (Jak)-associated IFN-alpha receptor to phosphorylate signal transducers and activators of transcription (STAT) and/or interferon regulatory factor-1 (IRF-1). However, IFN-tau-specific induction of GCP-2 may involve a variant type 1 receptor subunit or activators of transcription that are associated with protein kinase C and the Jak/STAT/IRF-1 pathway.

Hyperpolarized 3He NMR lineshape measurements in the live guinea pig lung

Spatially localized lineshapes of hyperpolarized (HP) 3He in guinea pig lungs have been measured in vivo. Three different axial slice locations, each containing different compositions of airway sizes and orientations, were studied. Gas peaks from major bronchi (2 ppm) and alveoli (-2 ppm) were distinguished. The gas phase spectra show structural features that are a result of frequency shifts caused by bulk magnetic susceptibility. For a given slice, the spectral lineshapes reflect the airway composition within the slice location, according to theory. The peak assignments given here also agree with previous studies done by Wagshul et al. with HP 129Xe. At each of the slice locations, data were acquired during two phases of the breathing cycle, resulting in a relative frequency shift of approximately 0.3 ppm in the superior slices. Spectra obtained over a number of breaths show the dynamics of the gas buildup in the lung and provide further evidence supporting the peak assignments.

Measuring the progression of foreign-body reaction to silicone implants using in vivo MR microscopy

We used in vivo magnetic resonance (MR) microscopy to follow the growth of fibrous capsule as a foreign body reaction to silicone implants in rats. Anesthetized rats were imaged 1, 7, 14, and 28 days after silicone-coated MR imaging coils were sutured to their neck muscles. On the twenty-eighth day, rats were sacrificed and coils and adjacent tissues were removed en bloc and fixed in formalin, reimaged with MR, and sectioned for conventional histology. Three-dimensional (3-D) spin-echo [3DFT] acquisition gave in-plane resolution of 32 x 32 microns in vivo and 16 x 16 microns ex vivo. All MR images showed a diffuse band of elevated signal intensity between the silicone of the coil and adjacent tissue. The border of the hyperintense band was thin and not well defined at seven days post-implantation. From 7-28 days, the band showed relatively homogeneous signal intensity and its thickness increased 44% on the rectus muscle side and 78% on the subcutaneous side. The capsule thickness determined either by MR in vivo and ex vivo microscopy or conventional histology was not significantly different, and there was a significant correlation between thickness measurements among those methods. MR in vivo microscopy provides sufficient resolution and spatial information to serially evaluate the growth of the foreign body fibrous capsule over time, thus achieving greater accuracy and consistency in measurements.

Time-course imaging of rat embryos in utero with magnetic resonance microscopy

Magnetic resonance (MR) microscopy was used to noninvasively investigate the development of live rat embryos in utero. The difficulty in making sequential observations of a developing mammalian embryo has frustrated developmental biologists for many years. Most current technologies analyze normal and abnormal development by observing end point phenotypes (in fixed specimens) rather than investigating the live embryo. MR microscopy was adapted to allow rat litters to be scanned three times each (at 1- to 3-day intervals) and has produced images of live developing embryos. It was demonstrated that repeated anesthesia and imaging protocols produced no gross malformations in the rat pups that were subsequently delivered and observed. Three-dimensional projection encoding with phase rewinders produced isotropic [256(3)] image data sets in about 30 minutes with excellent tissue contrast arising from steady-state effects in the amniotic fluid.

Pregnancy and interferon-tau induce conjugation of bovine ubiquitin cross-reactive protein to cytosolic uterine proteins

Conceptus-derived interferon-tau (IFN-tau) induces bovine endometrial ubiquitin cross-reactive protein (UCRP) mRNA and protein on Days 15-21 of pregnancy. Bovine UCRP retains the Leu-Arg-Gly-Gly C-terminal sequence of ubiquitin that ligates to and directs degradation of cytosolic proteins. The objectives of the present experiments were to determine whether UCRP became conjugated to endometrial cytosolic proteins during early pregnancy and in response to recombinant bovine (rbo) IFN-tau. Ubiquitin (8 kDa), UCRP (17 kDa), and conjugates thereof (> or = 30 kDa) were quantitated using Western blotting and densitometry. Endometrial ubiquitin and its conjugates did not differ between Day 18 pregnant and nonpregnant cows, or between control and rboIFN-tau-treated (25 nM) explant cultures (Day 14; nonpregnant). Bovine UCRP was induced in endometrium from pregnant as compared with nonpregnant cows. Conjugation of endometrial proteins to UCRP was induced in pregnant as compared to nonpregnant cows. Recombinant boIFN-tau induced UCRP and its conjugates in cultured endometrial explants from nonpregnant cows. It is concluded that UCRP, in response to rboIFN-tau, becomes conjugated to endometrial cytosolic proteins during early pregnancy. The regulation of uterine proteins by UCRP may be integral to the maintenance of early pregnancy in ruminants.

Laparoscopic paraaortic lymphadenectomy using laparosonic coagulating shears

With marked innovations in endosurgical instrumentation, operative laparoscopy to include lymphadenectomy has become feasible and has a valuable role in the management of gynecologic malignancy. We used laparosonic coagulating shears (LCS) for laparoscopic paraaortic lymphadenectomy in two women with cervical carcinoma. Operating times for the laparoscopic portion were 55 and 65 minutes and blood loss was 20 and 30 ml, respectively. No surgical complications were encountered. Lymphatic tissues were evaluated histologically and no thermal artifacts were identified. The major advantage of the ultrasonically activated scalpel of the LCS is the ability to cut and coagulate tissues simultaneously without electrical current. The LCS may afford the surgeon a greater margin of safety than unipolar electrocoagulation scissors by eliminating potential thermal and electrical injury to vital structures. Ultrasonic-activated technology deserves extended clinical investigation in laparoscopic lymphadenectomy to substantiate our preliminary findings, as well as to explore its potential in gynecologic oncology.

Magnetic resonance microscopy and histopathology: comparative approach of bromobenzene-induced hepatotoxicity in the rat

The development of magnetic resonance (MR) microscopy has provided new approaches to histology and histopathology. Recent work has shown the promise of increased sensitivity in animal models of chemically induced hepatotoxicity. However, the field is so new that there is little experience to relate changes seen in MR micrographs to the more traditional optical images stained with hematoxylin and eosin. This work compares the sensitivity and reproducibility of MR microscopy with conventional histopathology in detecting bromobenzene-induced hepatotoxicity in the rat. A time-course study was undertaken to provide a range of histopathologies. Specimens were studied at 24, 48, 72, and 96 hours after exposure to 10% of the median lethal dose of bromobenzene. Using 4 animals per group (a total of 32 rats) added statistical significance to the study and defined a range of interanimal variability over 96 hours. This work shows that MR microscopy, besides being nondestructive and three-dimensional, is at least as sensitive as conventional hematoxylin-eosin staining in detecting bromobenzene-induced centrilobular lesions and recovery of the hepatocellular architecture in the rat. This study further suggests that, as we begin to understand the underlying mechanisms of contrast in MR histology, MR may, in fact, supply even higher specificity than more traditional studies: variations were observed in MR images of treated livers at a given time point that could be not be differentiated based on the grading of necrosis and inflammation on hematoxylin-eosin-stained sections.

A fast spin echo technique with circular sampling

This paper presents a fast spin echo (FSE) imaging method that employs circular sampling of k-space. The technique has been implemented on a 2 Tesla imaging system and validated on both phantoms and living animals. Experimental studies have shown that circular sampling can produce artifact-free FSE images without the need of phase correction. Although not fully explored, preliminary results also show that circular sampling may have advantages over the conventional rectilinear FSE in signal-to-noise ratio and imaging efficiency. A major disadvantage is the increased sensitivity to off-resonance effects. The authors expect that the FSE technique with circular sampling will find its applications in magnetic resonance microscopy, neuro-functional imaging, and real-time dynamic studies.

MR microscopy of lung airways with hyperpolarized 3He

A technique using hyperpolarized (HP) 3He to image the small airways of the lung by using moderate flip angles and a short scanning period during early inspiration is demonstrated. Flip angles (alpha) ranging from 10-90 degrees were used in guinea pig experiments with scanning during the entire inspiration period. A second series acquired data throughout a short window of the ventilatory cycle with alpha = 45 degrees. The success of the animal studies has motivated implementation of similar imaging techniques in the clinical arena. Human studies involved imaging over the total inspiration period with alpha approximately 10 degrees. The first series of guinea pig experiments demonstrated that larger flip angles (50-90 degrees) destroy the magnetization before it reaches the smaller airways. At moderate flip angles (20-40 degrees), airway branching down to the fourth generation was apparent. Fifth-order branchings were seen in the images of the second series. The trachea down to fourth generation pulmonary airway branching, along with some distal air spaces, was seen in the human lung images.

Stability analysis of fixed points via chaos control

This paper reviews recent advances in the application of chaos control techniques to the stability analysis of two-dimensional dynamical systems. We demonstrate how the system's response to one or multiple feedback controllers can be utilized to calculate the characteristic multipliers associated with an unstable periodic orbit. The experimental results, obtained for a single and two coupled diode resonators, agree well with the presented theory. (c) 1997 American Institute of Physics.

MR microimaging of the lung using volume projection encoding

Radial acquisition (RA) techniques have been extended to produce isotropic, three-dimensional images of lung in live laboratory animals at spatial resolution down to 0.013 mm3 with a signal-to-noise ratio of 30:1. The pulse sequence and reconstruction algorithm have been adapted to allow acquisition of image matrices of up to 256(3) in less than 15 min. Scan-synchronous ventilation has been incorporated to limit breathing motion artifacts. The imaging sequence permits randomizing and/or discarding selected views to minimize the consequences of breathing motion. The signal in lung parenchyma was measured as a function of flip angle (alpha) for different repetition times and found to follow the predictions for which there is an optimum excitation (Ernst) angle. A single T1 relaxation value of 780 +/- 54 ms fits all data from six guinea pigs at 2.0 T. This T1 value parameterizes the signal and allows for a priori optimization, such as calculation of the Ernst angle appropriate for lung imaging.

Automated feedback control of body temperature for small animal studies with MR microscopy

A temperature control system consisting of a thermistor, signal processor, and computer algorithm was developed for magnetic resonance (MR) microscopy of small live animals. With control of body temperature within +/- 0.2 degree C of the set point, heart rate is stabilized and, in turn, repetition time (TR) during cardiac-gated studies is less variable. Thus, image quality and resolution are improved.

Transient ubiquitin cross-reactive protein gene expression in the bovine endometrium

Bovine ubiquitin cross-reactive protein (boUCRP) is secreted by the endometrium from days 15 to 26 of pregnancy in response to conceptus-derived interferon-tau (IFN-tau). We hypothesized that the gene encoding boUCRP was under transcriptional control by the conceptus and IFN-tau. Northern blots using radiolabeled UCRP cDNA revealed a single UCRP transcript of approximately 700 b that was present (P < 0.05) in endometrial cells cultured with 25 nM rboIFN-tau. The UCRP mRNA was not detected in endometrium on days 15, 17, 18 or 19 of the estrous cycle (n = 4 cows on each day) or in spleen, kidney, liver, corpus luteum or muscle. Bovine UCRP mRNA was detectable (P < 0.05) in endometrium from pregnant cows by day 15, reached highest levels by day 17, remained elevated on days 18, 19 and 21, and then declined to amounts on day 26 that were not detectable. Northern blot using radiolabeled ubiquitin cDNA revealed presence of the two major ubiquitin transcripts UbB (1.2 Kb) and UbC (2.6 Kb) in all tissues examined. The bovine UCRP cDNA did not cross-hybridize with these ubiquitin transcripts. We conclude that transcription of the UCRP gene is transient during early pregnancy and regulated by IFN-tau.

Dynamics of magnetization in hyperpolarized gas MRI of the lung

The magnetization in hyperpolarized gas (HP) MRI is generated by laser polarization that is independent of the magnet and imaging process. As a consequence, there is no equilibrium magnetization during the image acquisition. The competing processes of gas inflow and depolarization of the spins lead to large changes in signal as one samples k-space. A model is developed of dynamic changes in polarization of hyperpolarized 3He during infusion and in vivo imaging of the lung and verified experimentally in a live guinea pig. Projection encoding is used to measure the view-to-view variation with temporal resolution < 4 ms. Large excitation angles effectively sample the magnetization in the early stages of inflow, highlighting larger airways, while smaller excitation angles produce images of the more distal spaces. The work provides a basis for pulse sequences designed to effectively exploit HP MRI in the lung.

Progression of a focal ischemic lesion in rat brain during treatment with a novel glycine/NMDA antagonist: an in vivo three-dimensional diffusion-weighted MR microscopy study

Stroke was induced in two groups of anesthetized rats by occlusion of the middle cerebral artery (MCA) and ipsilateral common carotid artery. Group 1 (control) received vehicle and group 2 received the glycine N-methyl-D-aspartate (NMDA) antagonist ZD9379. Stroke volume was assessed by three-dimensional diffusion-weighted MR microscopy at 2.5 and 6 hours of MCA occlusion. At 2.5 hours, stroke volumes were identical in the two groups. At 6 hours, stroke volumes had increased by 15% in the control group; in contrast, the treated group showed a 40% reduced stroke volume. Conclusions from this in vivo study were as follows: (a) our technique allows more efficient and accurate measurement of stroke volume with an improvement in resolution over a previous method; (b) the ability to measure stroke volume at multiple time points shows volume change and assessment of time dependency of drug treatment; (c) at 6 hours, the glycine antagonist ZD9379 reduced stroke volume by 40%.

Epidermal growth factor receptor in vulvar malignancies and its relationship to metastasis and patient survival

OBJECTIVE

To evaluate the level of epidermal growth factor receptor (EGF-R) expression in vulvar malignancies and to determine if a correlation exists between EGF-R levels and metastasis or patient survival.

METHODS

All patients with a diagnosis of invasive squamous cell carcinoma of the vulva who were treated at our institution with a primary radical vulvectomy and inguinal lymph node dissection from 1983 to 1993 were eligible for the study. Sixty-one patients with available tissue blocks of benign vulvar epithelium, the primary malignant vulvar lesion, and groin node metastasis (when positive) were included in the study. Semiquantitative EGF-R expression was determined in a blinded fashion utilizing immunohistochemical staining of appropriate tissue samples. Survival was calculated utilizing Kaplan-Meier life table analysis based upon disease-free survival.

RESULTS

A significant increase (P < 0.001) in mean EGF-R levels was demonstrated in the primary tumor (67%) versus benign vulvar epithelium (31%). In the 14 patients with lymph node metastasis, the mean EGF-R level in the primary tumor was 65% versus 88% in the metastatic lesion (P < 0.001). The likelihood of lymph node metastasis was elevated in those patients with a benign tissue EGF-R level > or =40% (P < 0.03) and in those patients with a primary tumor EGF-R level > or =90% (P < 0.025). Life table analysis revealed a cumulative disease-free survival of 45% for all patients. Disease-free survival in those patients with EGF-R levels > or =90% in the primary tumor was 25%, contrasting with a disease-free survival of 54% in those patients with EGF-R levels <90% (P < 0.05).

CONCLUSIONS

There is a progressive increase in EGF-R expression from benign vulvar epithelium to primary malignant tissue to metastatic lesions within the same patient. Increased expression of EGF-R in the primary vulvar malignancy is significantly associated with lymph node metastasis and decreased patient survival. Increased expression of EGF-R in histologically benign vulvar epithelium has a significant association with lymph node metastasis and may predict decreased patient survival.

Feasibility of an immunoassay for mevalonolactone

Mevalonic acid is a key intermediate in a broad spectrum of cellular biological processes and their regulation. Availability of a rapid, sensitive and accurate method for its assay would be highly useful. Therefore, the feasibility of developing an immunoassay for mevalonic acid in biological samples was explored. The strategy employed was to synthesize several racemic haptens structurally resembling R-mevalonolactone, the cyclic form of mevalonic acid present at lower pH and presumed to be more antigenic. Two of these haptens were coupled to keyhole limpet hemocyanin, and the resulting conjugates were used successfully to generate antibodies in rabbits. The first antiserum bound to R,S-mevalonolactone much more effectively at pH 4.0 than at pH 6.0, consistent with the structural resemblance of the haptens to the lactone form. This antiserum also bound the free hapten from which it was generated and two others of different structure with comparable effectiveness; and slightly better than it bound R,S-mevalonolactone at pH 4.0. Similar results were obtained with the antiserum to the second hapten. The binding of either antiserum to the natural enantiomer, R-mevalonolactone, was 20 times weaker than to R,S-mevalonolactone, suggesting that the nonbiological enantiomer was more antigenic. Nevertheless, the results demonstrate that an immunochemical approach to accurate quantitation of mevalonic acid in biological samples is feasible.