Phase I trial of 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG) administered twice weekly

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Background: 17-DMAG binds to heat-shock protein 90, leading to degradation of oncogene client proteins, inhibiting tumor growth. Preclinically, 17-DMAG has potent antitumor activity. Methods: 17-DMAG was given by 1–2 hour infusion twice weekly for 4 weeks/28-day cycle. Starting dose: 1mg/m2/dose. Eligibility: ECOG = 2, adequate organ function. Exclusions: prolonged QTc/uncontrolled illness. An accelerated titration escalation design was used; one patient (pt)/dose level was entered until a single pt experienced dose-limiting toxicity (DLT) or 2 pts have grade (gr) = 2 toxicity during the first cycle. Ending the accelerated phase, it converts to a standard 3–6 pt/cohort design. Objectives: To determine the toxicity profile, pharmacokinetics (PK), pharmacodynamics (PD) and MTD of twice weekly 17-DMAG. Plasma samples collected before and up to 48 hours after 17-DMAG infusion were analyzed by LC-MS. Results: 23 pts were accrued and treated; Diagnosis: renal cell-1, pancreatic-2, medullary thyroid-1, NSCLC-3, colorectal -5, peritoneal mesotelioma-1 adrenocortical carcinoma-1, pheochromocytoma-2, malignant thymoma-1, melanoma-2, sarcoma-1, hepatocarcinoma-1 and head & neck -1 and ovary-1. 2 DLTs (gr 3 peripheral neuropathy and renal failure) were observed at 27 mg/m2/dose. Toxicities at the MTD dose (21 mg/m2/dose) have been acceptable: Myalgias/arthralgias being the most common. Other gr 1–2 toxicities included: diarrhea, weight loss, fatigue, elevated transaminases, hair loss, electrolyte abnormalities (hyponatremia and hypo/hyper-magnesemia) and leukocytopenia. PK is linear, with AUC and Cmax increasing as dose was escalated. Drug clearance is independent of dose, but highly variable (10.75 ± 5.56 L/hr/m2). Half-life: 10.0 to 31.7 h, with a median of 17.2 h. At the MTD: Cmax was 523.6 ± 265.3 ng/mL; Very high interindividual variability (CV = 70.3%) and a mean AUCinf of 2467.5 ± 1733.8 hr*ng/mL. Disease stabilization was achieved in a pt with mesothelioma (19 mos +) and another with head and neck cancer (8 mos +). Conclusions: We recommend 21mg/m2/dose twice weekly as the Phase II dose. The study continues to accrue at the MTD to collect paired biopsies for proteomic evaluation on Hsp90 client proteins analysis.

No significant financial relationships to disclose.

Quantitative liquid chromatographic-tandem mass spectrometric determination of reserpine in FVB/N mouse plasma using a "chelating" agent (disodium EDTA) for releasing protein-bound analytes during 96-well liquid-liquid extraction

A sensitive, specific, accurate and reproducible analytical method employing a divalent cation chelating agent (disodium EDTA) for sample treatment was developed to quantitate reserpine in FVB/N mouse plasma. Samples pretreated with 40 microl of 2% disodium EDTA in water were extracted by a semi-automated 96-well liquid-liquid extraction (LLE) procedure to isolate reserpine and a structural analog internal standard (I.S.), rescinnamine, from mouse plasma. The extracts were analyzed by turbo ionspray liquid chromatography-tandem mass spectrometry (LC-MS-MS) in the positive ion mode. Sample preparation time for conventional LLE was dramatically reduced by the semi-automated 96-well LLE approach. The assay demonstrated a lower limit of quantitation of 0.02 ng/ml using 0.1-ml plasma sample aliquots. The calibration curves were linear from 0.02 to 10 ng/ml for reserpine. The intra- and inter-assay precision of quality control (QC) samples ranged from 1.75 to 10.9% for reserpine. The intra- and inter-assay accuracy of QC samples ranged from -8.17 to 8.61%. Reserpine and the I.S. were found to be highly bound to FVB/N mouse plasma protein. This is the first report of disodium EDTA employed as a special protein-bound release agent to recover protein-bound analytes from plasma. These matrix effects and the effects of pH in the HPLC mobile phase on the sensitivities of LC-MS-MS are discussed in this paper.

The use of the polymerase chain reaction to detect bacteria in amniotic fluid in pregnancies complicated by preterm labor

OBJECTIVES

The purpose of this investigation was to determine the feasibility of using the polymerase chain reaction to detect bacteria in amniotic fluid and to compare pregnancy outcomes in subsets of women categorized by amniotic fluid culture, polymerase chain reaction, and interleukin-6 findings.

STUDY DESIGN

Amniotic fluid from 54 pregnancies with preterm labor and no clinical evidence of intraamniotic infection was evaluated with use of the polymerase chain reaction, interleukin-6, and bacterial culture. Gestational age, newborn weight, and time between amniocentesis and delivery were compared between subsets of women categorized by these tests.

RESULTS

With use of the polymerase chain reaction <100 bacteria per milliliter could be detected in amniotic fluid. A total of 55.5% of the amniotic fluid samples were polymerase chain reaction positive, whereas 9.2% of culture results were positive. Birth weights and gestational age at delivery were less and time from amniocentesis to delivery was shorter in the polymerase chain reaction-positive group (p < 0.05). Nine samples (15%) had elevated interleukin-6 concentrations; of these, six were polymerase chain reaction positive.

CONCLUSIONS

The polymerase chain reaction is a sensitive means of detecting bacteria in amniotic fluid. These results provide further evidence of an association between preterm delivery and intraamniotic infection. Not all amniotic fluid samples with elevated interleukin-6 levels have bacteria detectable by the polymerase chain reaction. We anticipate that the polymerase chain reaction will provide another avenue for the detection of bacteria in amniotic fluid.

Nutrition management in a pregnant comatose patient

Major intracranial injury or disease during pregnancy resulting in a comatose state presents unique and complex management challenges. Our patient is a 34-year-old woman who suffered a closed-head injury associated with spousal abuse at 22 weeks' gestation. This injury resulted in a large right frontoparietal hematoma that was subsequently evacuated via a right frontotemporal craniotomy 5 days after the injury. She remained in a vegetative state postoperatively. Aggressive nutrition support was provided with enteral feedings through a nasoduodenal feeding tube. Mild oligohydramnios was detected at 30 weeks' gestation and was subsequently determined to be due to preterm premature rupture of membranes. She was managed until 33 weeks' gestation, when signs of chorioamnionitis were noted. She then underwent a primary cesarean delivery and was delivered of an appropriate-for-gestational-age 2150-g viable male infant. The patient had progressive improvement in her mental status with occupational and physical therapy and was discharged on the 29th postpartum day. This case presents the nutrition and medical challenges of maintaining adequate maternal and fetal health in a pregnant comatose patient.

A retrospective analysis of laparoscopically assisted ventriculoperitoneal shunts

BACKGROUND

During the last two years, laparoscopy has been utilized to facilitate the rapid, safe and direct placement of the abdominal component of ventriculoperitoneal shunts. This study was undertaken to review the feasibility, benefits, technique, and clinical application of laparoscopically assisted ventriculoperitoneal (LAVP) shunt placement.

METHODS

A retrospective analysis of the records of six patients who underwent LAVP shunt placement was undertaken. The sex, age, technique, indication for surgery, comorbid conditions, complications operative time, results, and mortality were noted.

RESULTS

All patients underwent successful shunt placement. This included placement in the face of previous abdominal surgery, including a percutaneous gastrostomy. The one major complication, hemothorax, was not associated with the laparoscopic portion of the procedure.

CONCLUSIONS

Using basic laparoscopic skills and nonspecialized equipment, laparoscopic assistance in ventriculoperitoneal shunt placement offers easy, direct placement of the intraabdominal portion of the catheter in most situations and provides definite patient benefits.

Prediction of fetal macrosomia using humeral soft tissue thickness

OBJECTIVE

To determine the usefulness of an objective assessment of humeral soft tissue thickness in estimating birth weight in a population at risk for macrosomia.

METHODS

Shortly before delivery, ultrasound examinations were performed on 95 women at risk of having macrosomic infants. In each case, the fetal humeral soft tissue thickness (the distance between the outer edge of the humerus to the skin surface on transverse views of the upper arm) was measured three times, and an average was taken.

RESULTS

The humeral soft tissue thickness correlated significantly with birth weight (R2 = 0.40, P < .001) and ponderal index (R2 = 0.20, P = .02). The humeral soft tissue thickness was significantly higher in macrosomic infants (P < .001), in those with an abnormally high ponderal index (P = .02), and in infants whose deliveries were complicated by shoulder dystocia (P = .05). There was no apparent effect of maternal diabetes on the humeral soft tissue thickness. The humeral soft tissue thickness was more sensitive in predicting macrosomia than was the ultrasound-estimated fetal weight (88 versus 71%), but less specific (75 versus 91%).

CONCLUSION

The humeral soft tissue thickness correlates with birth weight. However, its clinical use compared with other predictors remains to be defined.

Classification of endometrial cells on cervical cytology

One hundred eighty-eight women who had endometrial cells on cervical cytologic specimens during the secretory phase or in the postmenopausal period were studied retrospectively. Each had undergone hysterectomy or endometrial biopsy within 12 months of the original smear. The endometrial cells were classified as typical, atypical, or suspicious for carcinoma. Among premenopausal subjects, three of 57 with typical cells had endometrial hyperplasia, one of two with atypical cells had endometrial polyps, and both with cells suspicious for carcinoma had endometrial carcinoma. In the postmenopausal group, ten (13.5%) of 74 with typical endometrial cells had either hyperplasia or carcinoma, and five (22.7%) of 22 with atypical cells and 24 77.4%) of 31 patients with suspicious cells had either hyperplasia or carcinoma. The present findings and a review of the pertinent literature demonstrate that the classification system used is helpful in predicting the risk for endometrial disease in patients with endometrial cells seen on cervical cytologic smears during the secretory phase or in the postmenopausal period.

Urinary profiles of organic acids and volatile metabolites during the starvation process in rats

Capillary gas chromatographic procedures were used to quantify the volatile and acidic compound profiles in the urinary samples of Sprague-Dawley rats during the starvation and refeeding periods. Numerous metabolites, identified through mass spectrometry, showed significant variations due to these physiological processes. Correlations are attempted with the previously studied biochemical processes in diabetic animals.

Quantitative alterations in the metabolism of carbonyl compounds due to diet-induced lipid peroxidation in rats

Following the dietary induction of lipid peroxidation in rats (verified by the levels of malonaldehyde and glutathione peroxidase), the urinary carbonyl compounds were followed chromatographically. Through a headspace gas chromatographic procedure, increases of several aldehydes and furan derivatives were noticed. Liquid chromatography of the dinitrophenylhydrazone derivatives of urinary carbonyls provided a more definitive experiment, in which the increased-peroxidation animals could be compared to those maintained on a control diet. Several carbonyl metabolites, identified by mass spectrometry, were elevated following the lipid peroxidation induction.