Using tumor growth rate to inform treatment efficacy in pancreatic adenocarcinoma: From the metastatic to the neoadjuvant setting

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Background: The development of new treatments in oncology is a long, costly, and, too often, unsuccessful process. Methods for screening agents earlier in development and strategies for conducting smaller randomized controlled trials are needed. Methods: We used a mathematical model of tumor growth kinetics fit to serial radiographic tumor measurements or CA19-9 values to estimate rates of exponential tumor growth [g] and decay [d] during treatment for pancreatic ductal adenocarcinoma (PDAC). Results: We retrospectively collected and analyzed data from 2691 patients with stage III-IV PDAC who were enrolled in five clinical trials or were included in two large real-world data sets from Columbia University Irving Medical Center and Veterans Administration Medical Centers. Using log-rank comparison of Kaplan-Meier plots by quartile of g, we found that in patients with metastatic PDAC g correlates highly with overall (OS) and progression-free survival (PFS) (p<0.001), with slower g associated with improved survival in this population. Pairwise comparisons showed significantly slower median g in the experimental arm versus control arm in the pivotal trials analyzed (p<0.001). At the individual patient level, g was significantly faster for liver metastases as compared to primary pancreatic tumors and g consistently increased towards the end of therapy (often a threefold increase) suggesting development of chemoresistance. In addition to utility in the metastatic setting, a pilot analysis of data from a prospective study of patients treated with gemcitabine + docetaxel + capecitabine (GTX) in the neoadjuvant setting suggests that the emergence of a detectable g during neoadjuvant therapy may portend worse OS following surgery though sample size was small (n=45, median OS with detectable g 13.6 m v 33.1 without detectable g, p =0.35). Conclusions: We applied a tumor growth model to the data of over 2500 patients with PDAC and showed that g is inversely associated with survival in this population. Given the strong association between g and survival, g could be useful in clinical trials as an informative endpoint to expedite the assessment of novel therapies for the treatment of PDAC. Furthermore, g offers valuable patient-level data, including trends in resistance and variations in growth rate by metastatic disease site We plan to evaluate whether the emergence of g during neoadjuvant therapy should be considered a prompt to change treatment regimens.

Tumor Growth Rate Informs Treatment Efficacy in Metastatic Pancreatic Adenocarcinoma: Application of a Growth and Regression Model to Pivotal Trial and Real-World Data

BACKGROUND

Methods for screening agents earlier in development and strategies for conducting smaller randomized controlled trials (RCTs) are needed.

METHODS

We retrospectively applied a tumor growth model to estimate the rates of growth of pancreatic cancer using radiographic tumor measurements or serum CA 19-9 values from 3033 patients with stages III-IV PDAC who were enrolled in 8 clinical trials or were included in 2 large real-world data sets.

RESULTS

g correlated inversely with OS and was consistently lower in the experimental arms than in the control arms of RCTs. At the individual patient level, g was significantly faster for lesions metastatic to the liver relative to those localized to the pancreas. Regardless of regimen, g increased toward the end of therapy, often by over 3-fold.

CONCLUSIONS

Growth rates of PDAC can be determined using radiographic tumor measurement and CA 19-9 values. g is inversely associated with OS and can differentiate therapies within the same trial and across trials. g can also be used to characterize changes in the behavior of an individual's PDAC, such as differences in the growth rate of lesions based on metastatic site, and the emergence of chemoresistance. We provide examples of how g can be used to benchmark phase II and III clinical data to a virtual reference arm to inform go/no go decisions and consider novel trial designs to optimize and accelerate drug development.

Fc galactosylation follows consecutive reaction kinetics and enhances immunoglobulin G hexamerization for complement activation

Fc galactosylation is a critical quality attribute for anti-tumor recombinant immunoglobulin G (IgG)-based monoclonal antibody (mAb) therapeutics with complement-dependent cytotoxicity (CDC) as the mechanism of action. Although the correlation between galactosylation and CDC has been known, the underlying structure–function relationship is unclear. Heterogeneity of the Fc N-glycosylation produced by Chinese hamster ovary (CHO) cell culture biomanufacturing process leads to variable CDC potency. Here, we derived a kinetic model of galactose transfer reaction in the Golgi apparatus and used this model to determine the correlation between differently galactosylated species from CHO cell culture process. The model was validated by a retrospective data analysis of more than 800 historical samples from small-scale and large-scale CHO cell cultures. Furthermore, using various analytical technologies, we discovered the molecular basis for Fc glycan terminal galactosylation changing the three-dimensional conformation of the Fc, which facilitates the IgG1 hexamerization, thus enhancing C1q avidity and subsequent complement activation. Our study offers insight into the formation of galactosylated species, as well as a novel three-dimensional understanding of the structure–function relationship of terminal galactose to complement activation in mAb therapeutics.

User and system pitfalls in liver imaging with LI-RADS

The Liver Imaging Reporting and Data System (LI-RADS) is a comprehensive system for standardizing the terminology, technique, interpretation, reporting, and data collection of liver imaging, created specifically for patients at risk for hepatocellular carcinoma. Over the past years, LI-RADS has been progressively implemented into clinical practice, but pitfalls remain related to user error and inherent limitations of the system. User pitfalls include the inappropriate application of LI-RADS to a low-risk patient population, incorrect measurement techniques, inaccurate assumptions about LI-RADS requirements, and improper usage of LI-RADS terminology and categories. System pitfalls include areas of discordance with the Organ Procurement and Transplantation Network (OPTN) as well as pitfalls related to rare ancillary features. This article reviews common user pitfalls in applying LI-RADS v2018 and how to avoid preventable errors and also highlights deficiencies of the current version of LI-RADS and how it might be improved in the future. Level of Evidence:3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019. J. Magn. Reson. Imaging 2019;50:1673-1686.

CT/MR LI-RADS 2018: clinical implications and management recommendations

Unique among solid organ tumors, hepatocellular carcinoma (HCC), may be diagnosed by imaging alone, without the need for biopsy. The Liver Imaging Reporting and Data System (LI-RADS) was developed to provide high-specificity diagnosis of HCC based on imaging while also standardizing the assessment and reporting of the entire spectrum of lesions and pseudolesions encountered in patients at risk for this malignancy. In this pictorial review, we discuss management recommendations associated with CT/MR LI-RADS observations. We emphasize the rationale for the recommendations and the role of multidisciplinary management discussion, and we provide a framework for standardized reporting. Management of patients who undergo ultrasound (US) for screening and surveillance or those who undergo diagnostic contrast-enhanced ultrasound (CEUS) is beyond the scope of this paper.

Uber die chemische Natur des Thromboplastins aus menschlicher Hirnsubstanz

Die Frage, ob Thromboplastin aus menschlichem Hirngewebe eine eiweißhaltige Substanz ist oder nicht, wurde neuerdings untersucht. Nach Deutsch und Mitarb. (5) enthält humanes Hirnthromboplastin Eiweiß im Widerspruch mit früheren von Hecht md Mitarb. (17) mit Kaninchenhirn erhaltenen Befunden.

Die Ergebnisse der gegenwärtigen Nachuntersuchung mit menschlicher Hirnlubstanz waren:

1. Die von Deutsch beschriebene Spaltung des Thromboplastins in eine Lipoidund )ine Eiweißkomponente unter Verwendung von Pyridin konnte nicht bestätigt verden.

2. In Deutschs sog. Eiweißfraktion konnten kleine Mengen von ungefähr 15 verschiedenen Aminosäuren mit Hilfe zweidimensionaler Chromatographie nach Hydro y se nachgewiesen werden. Diese sind auch in der Lipoidfraktion und in allen bei der Reinigung des Thromboplastins erhaltenen Waschflüssigkeiten und in den Pyridinextrakten, die der Entfernung der Lipoide aus der Eiweißfraktion dienen sollten, anwesend.

3. Gereinigtes Thromboplastin und dessen beide Fraktionen geben negative Biuretreaktionen; analytische Einzelheiten und die Untersuchung mit Hilfe der Polyacrylamidelektrophorese sprachen nicht für das Vorliegen von Eiweiß.

4. Deutschs analytische Resultate bzgl. der »Eiweiß«-Eraktion konnten nicht bestätigt werden.

5. Es wurden von dem Thromboplastin, dessen Lipoidund Eiweißfraktion sowie von allen Waschflüssigkeiten qualitativ identische Chromatogramme erhalten. Einund zweidimensionale Papier Chromatographie, Kieselgeldünnschicht Chromatographie und Trikomplexfärbung wurden verwendet.

6. Die nach Hydrolyse Aminosäuren liefernde Fraktion konnte isoliert und analysiert werden.

7. Es konnte jedoch nicht mit Sicherheit entschieden werden, ob die kleinen Mengen Aminosäuren liefernde Substanz (en) als Verunreinigungen von dem ursprünglich wässerigen Gewebeextrakt aus Hirnsubstanz, die nicht vollständig entfernt werden konnten, stammen, oder als molekuläre Bestandteile von Phospholipidmolekülen auf gef aßt werden müssen. Bis jetzt scheint die erstgenannte Auffassung wahrscheinlicher zu sein.

On the Functional Resynthesis of Thromboplastin (“TP”) from its Fractions and Various Substitutes

Recombination of the low active lipid fraction with the inactive non-lipid fraction of brain thromboplastin has been proved to be just as successful in restoring the original high thromboplastic activity as the recombination of the corresponding material obtained from lung thromboplastin.

The properties of the individual components, of thromboplastin, its fractions obtained by different ways, and of their substitutes were studied comparatively; the influence of the solvents used was also investigated.

Experiences obtained were collected to prepare a high active and stable brain thromboplastin.

Only the lipid- and non-lipid fraction obtained by pyridin is successful in regenerating the original thromboplastic activity, in contrast with the reunion of both fractions produced by Sephadex G-25, Sephadex LH-20 and butanol.

The lipid fraction can be fully replaced by the lipid activator, PE from soy-beans and partly by synthetic dioleoyl PE, however this is not possible with natural and synthetic PC and lyso PC.

The results of experiments to replace the non-lipid fraction by various amino acids, peptides or proteins were poor.

A full regeneration of the thromboplastic activity with the suspended fractions is only successful after a previous solution of the components in pyridin or chloroform and evaporation.

The rebuilt of the original thromboplastic activity was complete only as long as contaminated non-lipid fractions were used. Non-lipid fractions, quantitatively free of lipids, were ineffective.

Versuche zur chemischen Identifikation und Synthese von Gerinnungsfaktoren

1. Mit Hilfe einer ausführlichen Einleitung wurde versucht, die Grundlage zum müheloseren Verständnis der vorliegenden Untersuchung zu schaffen.

2. Die Resultate einer Studie mit fünf verschiedenen synthetischen Kephalinen waren:

a) Die synthetischen Kephaline sind im Gegensatz zu den lipoiden Aktivatoren und dem von Paul s sen untersuchten Lipoidextrakt aus den Blutplättchen gegenüber Hühnerplasma und menschlichem Plasma inaktiv.

b) Ebensowenig können die Kephaline die Rolle der sub a) genannten Substanzen im Rahmen der Sphingosinreaktionen übernehmen.

c) Die Kephaline sind nicht imstand im Thrombokinasebildungstest die Funktion der Thrombozyten zu erfüllen, wozu die Lipoidextrakte aus denselben und ebenso die lipoiden Aktivatoren befähigt sind.

d) Alle synthetischen Kephaline geben anläßlich ihrer papierchromatographi-schen Untersuchung andere Ninhydrin-positive Reaktionen wie Lipoidextrakte aus den Blutplättchen und die lipoiden Aktivatoren.

3. Die sub 2 genannten Befunde werden als weitere Argumente gegen die Auffassung von der Identität des lipoiden Aktivators mit dem Kephalin klassischer Prägung gedeutet.

4. Die typischen Reaktionen des aus physiologischem Material isolierten Inhibitors Sphingosin werden in noch stärkerem Maß von der synthetisch bereiteten Verbindung gegeben.

5. Die Untersuchung von 8 synthetischen Derivaten, Isomeren und Homologen des Sphingosins zeigte, daß zum Erhalt der maximalen Sphingosinreaktionen sowohl die Doppelbindung als auch die freien OH- und NH2-Gruppen erforderlich sind.

Studien über den lipoiden Aktivator der Blutgerinnung

1. Neben anderen angewandten Methoden wird eine ausführliche Beschreibung unserer Technik des Thrombokinasebildungstestes gegeben.

2. Die lipoiden Aktivatoren aus Aceton-getrocknetem Gehirn von Mensch, Rind, Pferd, Schwein, Kaninchen und Taube wurden vergleichend untersucht.

3. Die lipoiden Aktivatoren zeigen ein identisches Verhalten

a) bezüglich ihres Einflusses auf die Gerinnung sowohl von Hühnerplasma als auch von menschlichem Plasma,

b) bezüglich des negativen Ausfalls der Eiweißreaktionen,

c) hinsichtlich der RF-Werte der papierchromatographisch erhaltenen vier Ninhydrin-positiven Reaktionen und

d) bezüglich ihrer gleichwertigen Leistung, die Blutplättchen im Rahmen des Thrombokinasebildungstestes zu ersetzen.

Die aus Hirnsubstanz erhältlichen lipoiden Aktivatoren scheinen demnach identisch zu sein.

4. Die Aktivitätskurven der aus den gleichen Aceton-getrockneten Hirnsubstanzen stammenden Thrombokinasen mit Hühner- und menschlichem Plasma als Gerinnungssubstrat weichen von den Aktivitätskurven der entsprechenden lipoiden Aktivatoren in spezifischer Weise ab.

5. An Hand orientierender Versuche, welche die Eiweißfreiheit der Hirnthrombokinasen suggerieren, wird erwogen, die unter 4. genannten Beobachtungen u. a. den Unterschieden in der lipoiden Zusammensetzung der Präparate zuzuschreiben.

Predictors of Response and Survival in Locally Advanced Adenocarcinoma of the Pancreas Following Neoadjuvant GTX with or Without Radiation Therapy

LESSONS LEARNED

There is no presenting parameter that predicts the success of neoadjuvant therapy for pancreatic cancer.Despite the images on scans following neoadjuvant therapy, all patients should be evaluated, because inflammation following radiation therapy (RT) may overstate the extent of tumor and vascular involvement.

BACKGROUND

In patients presenting with locally advanced pancreatic adenocarcinoma deemed unresectable by two pancreatic cancer surgeons, we analyzed presenting tumor size, extent of vascular involvement, tumor markers, response to neoadjuvant gemcitabine (G), docetaxel (T), and capecitabine (X) with or without additional chemoradiotherapy with GX on R0 resection rates (≥2 mm margins), and survival.

METHODS

All patients had baseline magnetic resonance imaging (MRI) and/or computed tomography (CT) scans and endoscopic ultrasound. A baseline positron emission tomography-computed tomography (PET-CT) was performed in 39 patients. The scans were reviewed by two radiologists.GTX (gemcitabine 750 mg/m² and docetaxel 30 mg/m² on days 4 and 11 with capecitabine 1,500 mg/m² days 1-14) was administered on a 3-week schedule for 6 cycles to patients with both arterial and venous-only involvement. Patients in the arterial arm received GX/RT before surgery, and those in the venous arm received GX/RT after R1 resection. Standard-dose RT was delivered by intensity-modulated radiation therapy (IMRT) or conformal fields to 5040 cGy along with capecitabine for 5 days and gemcitabine on day 5 of weeks 1, 2, 4, and 5 of RT, starting with the first full week of RT.A cancer antigen test 19-9 (CA 19-9) was obtained at baseline and days 4 and 11 of each cycle. The rate of change in CA 19-9 was calculated using the formula: (Log₁₀ CA 19-9 time 0) - (Log₁₀ CA 19-9 at 9 weeks)/9 weeks. This was derived based on the observation that the fall in CA 19-9 following effective chemotherapy is a second-order function.

RESULTS

Of the 34 patients with arterial involvement and 11 with extensive venous involvement who met the eligibility criteria and began GTX, only 5 patients in the arterial arm did not undergo subsequent resection. The remaining 40 patients were included in this analysis of presenting parameters with respect to R0 resection, disease-free survival (DFS), and overall survival (OS). R0 resection was achieved in 28 of 40 patients (70%), and R1 resection in the remaining 12 (30%). The OS after R0 resection was a median 37 months (95% confidence interval [CI]: 29.3-44.7) compared with 29 months (95% CI: 28.5-41.5) for those with R1 resection.Excluding four postoperative deaths, median DFS for the 25 (71%) with R0 resection was 31 months (95% CI: 11.3-51.1), and the median DFS for R1 resection was only 14 months (95% CI: 11.1-17). Eleven of the twenty-eight (39%) patients achieving R0 resection have not relapsed (median = 45 months, range = 25-71 months).

CONCLUSION

R0 resection, the goal of neoadjuvant treatment, can be achieved in 70% of patients presenting with locally advanced pancreatic cancer. The median DFS was 31 months (95% CI: 11. 3-51.1). No relationship was found with tumor size, degree of vascular involvement, carcinoembryonic antigen test (CEA), CA 19-9, degree of tumor regression on scan, fall in CA 19-9, or SUV on PET scan and subsequent survival.

Characterization of the Binding Site of Aspartame in the Human Sweet Taste Receptor

The sweet taste receptor, a heterodimeric G protein-coupled receptor comprised of T1R2 and T1R3, binds sugars, small molecule sweeteners, and sweet proteins to multiple binding sites. The dipeptide sweetener, aspartame binds in the Venus Flytrap Module (VFTM) of T1R2. We developed homology models of the open and closed forms of human T1R2 and human T1R3 VFTMs and their dimers and then docked aspartame into the closed form of T1R2's VFTM. To test and refine the predictions of our model, we mutated various T1R2 VFTM residues, assayed activity of the mutants and identified 11 critical residues (S40, Y103, D142, S144, S165, S168, Y215, D278, E302, D307, and R383) in and proximal to the binding pocket of the sweet taste receptor that are important for ligand recognition and activity of aspartame. Furthermore, we propose that binding is dependent on 2 water molecules situated in the ligand pocket that bridge 2 carbonyl groups of aspartame to residues D142 and L279. These results shed light on the activation mechanism and how signal transmission arising from the extracellular domain of the T1R2 monomer of the sweet receptor leads to the perception of sweet taste.

[In-vivo Confocal Microscopy for the Diagnosis of Mucous Membrane Pemphigoid]

BACKGROUND

An early diagnosis is crucial for the outcome of mucous membrane pemphigoid (MMP). The sensitivity of the so-called diagnostic gold standard, direct and indirect immune fluorescence (DIF/IIF) ranges from 30 to 80 %, and is thus lower than desirable. Moreover, conjunctival biopsy, mandatory in most cases, entails the risks of exacerbation. The purpose of this study is to establish the contribution of non-invasive in vivo confocal microscopy to the recognition of MMP.

PATIENTS AND METHODS

We examined the conjunctiva of ten patients and ten control subjects with the confocal microscope Heidelberg Retina Tomograph II/Rostock Cornea Module and checked for differences in qualitative and quantitative structure of the connective tissue.

RESULTS

Pemphigoid patients showed an increase and/or aggregation of reticular connective tissue with hyperreflective strands in the substantia propria, as well as an increased subepithelial fibrosis compared to controls. The basal membrane zone was thicker and more hyperreflective than in the healthy subjects.

CONCLUSION

In-vivo confocal microscopy may serve as a useful additional diagnostic method in the detection of MMP.

Neoadjuvant gemcitabine, docetaxel, and capecitabine followed by gemcitabine and capecitabine/radiation therapy and surgery in locally advanced, unresectable pancreatic adenocarcinoma

BACKGROUND

This prospective study was undertaken to assess toxicity, resectability, and survival in pancreatic adenocarcinoma patients presenting with locally advanced, unresectable disease treated with neoadjuvant gemcitabine, docetaxel, and capecitabine (GTX) and gemcitabine and capecitabine (GX)/radiation therapy (RT).

METHODS

All patients presenting to the Pancreas Center were evaluated for eligibility. Forty-five patients (mean age, 64 years; range, 44-83 years)-34 patients deemed unresectable because of arterial involvement and 11 patients deemed unresectable because of extensive venous involvement-were treated with 6 cycles of GTX. Those with arterial involvement were treated with GX/RT after chemotherapy.

RESULTS

The GTX and GX/RT treatments were tolerated with the expected drug-related toxicities. There were no bowel perforations, cases of pancreatitis, or delayed strictures. Among those with arterial involvement, 29 underwent subsequent resection, with 20 (69%) achieving R0 resections. All 11 patients with venous-only involvement underwent resection, with 8 achieving R0 resections and 3 achieving complete pathologic responses. For the arterial arm, the 1-year survival rate was 71% (24 of 34 patients), and the median survival was 29 months (95% confidence interval, 21-38 months). Thirteen patients (38%) have not relapsed (range, 5-49+ months). For the venous arm, the median survival has not been reached at more than 42 months. Six patients (55%) in the venous arm did not experience recurrence (range, 6.2-42+ months).

CONCLUSIONS

GTX plus GX/RT is an effective neoadjuvant regimen that can be safely administered to patients up to at least the age of 83 years. It is associated with a high response rate, a high rate of R0 resections, and prolonged overall survival.

Dextran coated bismuth-iron oxide nanohybrid contrast agents for computed tomography and magnetic resonance imaging

Bismuth nanoparticles have been proposed as a novel CT contrast agent, however few syntheses of biocompatible bismuth nanoparticles have been achieved. We herein report the synthesis of composite bismuth-iron oxide nanoparticles (BION) that are based on a clinically approved, dextran-coated iron oxide formulation; the particles have the advantage of acting as contrast agents for both CT and MRI. BION were synthesized and characterized using various analytical methods. BION CT phantom images revealed that the X-ray attenuation of the different formulations was dependent upon the amount of bismuth present in the nanoparticle, while T₂-weighted MRI contrast decreased with increasing bismuth content. No cytotoxicity was observed in Hep G2 and BJ5ta cells after 24 hours incubation with BION. The above properties, as well as the yield of synthesis and bismuth inclusion efficiency, led us to select the Bi-30 formulation for in vivo experiments, performed in mice using a micro-CT and a 9.4 T MRI system. X-ray contrast was observed in the heart and blood vessels over a 2 hour period, indicating that Bi-30 has a prolonged circulation half-life. Considerable signal loss in T₂-weighted MR images was observed in the liver compared to pre-injection scans. Evaluation of the biodistribution of Bi-30 revealed that bismuth is excreted via the urine, with significant concentrations found in the kidneys and urine. In vitro experiments confirmed the degradability of Bi-30. In summary, dextran coated BION are biocompatible, biodegradable, possess strong X-ray attenuation properties and also can be used as T₂-weighted MR contrast agents.

Dual source computed tomography coronary angiography in new onset cardiomyopathy

AIM: To evaluate safety and utility of coronary computed tomography angiography (CCTA) compared to invasive coronary angiography (ICA) in new cardiomyopathy.

METHODS: Eighteen patients (mean age 56.5 years, 10 males) who presented for evaluation of new onset heart failure with evidence of systolic dysfunction (ejection fraction < 40%) on echocardiography and recent ICA were prospectively enrolled. Patients with known coronary artery disease, atrial fibrillation, creatinine > 1.5 g/dL, and contraindication to intravenous contrast administration were excluded. CCTA was performed using a dual source 64-slice scanner. Mean heart rate was 75 beats per minute. Stenosis was graded for each coronary segment as: none, mild (< 50%), moderate (50%-70%), severe (> 70%), or non-evaluable. Ischemic cardiomyopathy (ICM) was diagnosed if severe stenosis was present in the left main, proximal left anterior descending artery, or two or more major arteries.

RESULTS: Two patients were diagnosed with ICM by ICA. CCTA correctly identified 2 patients with ICM and 16 patients as non-ICM. CCTA successfully evaluated 240/246 coronary segments with an accuracy of 97.5%, sensitivity 70%, specificity 98.7%, positive predictive value of 70%, and negative predictive value of 98.7% for identifying severe stenosis on a per-segment level.

CONCLUSION: Dual source 64-slice multi-detector CCTA is a safe, accurate, and non-invasive technique for diagnosing ICM in patients presenting during the acute phase of newly diagnosed cardiomyopathy.

CT and MR Imaging of Complications of Partial Nephrectomy

The standard treatment for renal cell carcinoma for many years was radical nephrectomy, but in the past decade there has been a trend toward elective nephron-sparing surgery. Initially, partial nephrectomy was performed with an open surgical approach; more recently and with increasing frequency, a laparoscopic approach has been used in selected cases. Nephron-sparing surgery with either approach is more complex than is traditional radical nephrectomy and more frequently results in complications. The possible complications of partial nephrectomy include vascular, collecting system, and technical complications as well as recurrent tumor and infection. For prompt diagnosis and appropriate management of these complications, radiologists must be familiar with normal and abnormal features in the postoperative appearance of the kidney at computed tomography and magnetic resonance imaging.

Quadricuspid Aortic Valve

Cardiac multidetector helical computed tomography angiogram (MDCTA) findings of a quadricuspid aortic valve are presented. MDCTA enabled evaluation of the aortic valve and its function, the coronary arteries, and left ventricular function. This case is, to our knowledge, the first description of the MDCTA imaging appearance of quadricuspid aortic valve.

The use of opposed-phase chemical shift MRI in the diagnosis of renal angiomyolipomas

OBJECTIVE

The objective of our study was to determine the reliability of the location of the india ink artifact and signal loss on opposed-phase chemical shift MRI to differentiate angiomyolipomas from solid renal masses and from hemorrhagic-proteinaceous renal cysts.

MATERIALS AND METHODS

Twenty-three angiomyolipomas, 24 hemorrhagic-proteinaceous cysts, and 23 solid renal masses (nonangiomyolipomas) were retrospectively evaluated at 1.5 T with chemical shift MRI using TEs of 2.1-2.7 msec (opposed phase) and 4.8-5.3 msec (in phase). Two independent observers reviewed the MR images for signal loss on opposed-phase images and for the presence or absence of india ink artifact. An angiomyolipoma was diagnosed if the india ink artifact was identified at the interface of the mass and the kidney or was present within the renal mass.

RESULTS

Twenty-three (100%) of the 23 angiomyolipomas showed india ink artifact within the mass or at its interface with the kidney, and 18 (78.3%) of the 23 angiomyolipomas showed signal loss on opposed-phase MR images. In 24 (100%) of the 24 hemorrhagic-proteinaceous cysts, india ink artifact was not present within the mass or at its interface with the kidney. No signal loss was seen in hemorrhagic-proteinaceous cysts on opposed-phase MR images. In one (4%) of the 23 solid (nonangiomyolipoma) renal masses, the india ink artifact was identified at the interface of the mass with the kidney, and in two (9%) of the 23 masses, loss of signal was identified on the opposed-phase MR images.

CONCLUSION

The presence of india artifact at a renal mass-kidney interface or within a renal mass is indicative of angiomyolipoma.

Urinary tract infections associated with otitis media in infants and children

One hundred six infants and children with otitis media were screened for the incidence of urinary tract infections (UTI) by urine culture. Seventeen patients (16%) who had UTI were compared with the 80 patients with sterile urine for differences in host factors and laboratory features. The mean age, WBC counts, and ESR values were similar. Patients with UTI-associated otitis media had a higher incidence of hematuria. Prevalence of high (greater than or equal to 103 degrees F) fever was higher among the boys with UTI. However, because of the lack of definite clinical and laboratory clues to determine the presence or absence of UTI, urine culture is the only test to uncover otitis media patients with concomitant UTI.

Marijuana smoking: effect on expired air carbon monoxide levels

A group of regular marijuana smokers was given expired air carbon monoxide (CO) tests before and after smoking low-dose, high-dose, and placebo marijuana cigarettes. Expired air CO doubled following smoking. There were no significant differences in CO levels in the different dose categories. Studies of the effects of marijuana on the body should attempt to separate effects of the drug from the effects that are secondary to the method of intake.

Increased verbal interaction via group techniques with regressed schizophrenics

Verbal interaction on the tenth 50-min. session of remotivation therapy for 8 hospitalized male chronic schizophrenics ( Mage = 57.87) increased significantly over the level for 8 comparable schizophrenic patients who served as controls. Increased verbal interaction appeared on both a structured and an unstructured task. Although individual differences were marked, the efficacy of remotivation therapy with chronic schizophrenics is suggested.

Graded group procedures for long term regressed schizophrenics

It has been suggested that a graded sequence of treatments might be the most efficacious approach to the rehabilitation of the regressed schizophrenic. To date, however, no research has been reported which examines the relative effectiveness of various treatment combinations with this difficult population. The present study is an investigation of the relative effectiveness of three treatment sequences in increasing social interaction among long term regressed schizophrenics. In this study, 32 chronic schizophrenic patients were randomly assigned to one of three treatment sequences or to a control group. Each sequence began with six sessions of remotivation group therapy. Following, this, one group participated in four sessions of activities, another had social living discussions, and a third continued with remotivation therapy. Both the remotivation-activities sequence and the remotivation-only sesequence significantly increased social interaction relative to the remotivation-social living sequence and thecontrol group. Therefore it appears that both the activities groups and the remotivation groups are effective early components of a graded treatment program to increase social interaction among withdrawn schizophrenics.