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T15NT was added to a soil of low organic carbon content and composted for 20 days in an aerobic bench scale reactor. The finished whole compost and fulvic acid, humic acid, humin, and lignocellulose fractions extracted from the compost were analyzed by solid-state CP/MAS and DP/MAS 15N NMR. 15N NMR spectra provided direct spectroscopic evidence for reduction of TNT followed by covalent binding of the reduced metabolites to organic matter of the composted soil, with the majority of metabolite found in the lignocellulose fraction, by mass also the major fraction of the compost. In general, the types of bonds formed between soil organic matter and reduced TNT amines in controlled laboratory reactions were observed in the spectra of the whole compost and fractions, confirming that during composting TNT is reduced to amines that form covalent bonds with organic matter through aminohydroquinone, aminoquinone, heterocyclic, and imine linkages, among others. Concentrations of imine nitrogens in the compost spectra suggest that covalent binding by the diamines 2,4DANT and 2,6DANT is a significant process in the transformation of TNT into bound residues. Liquid-phase 15N NMR spectra of the fulvic acid and humin fractions provided possible evidence for involvement of phenoloxidase enzymes in covalent bond formation.

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Previous studies of the removal of implantable cardioverter defibrillator (ICD) leads have been restricted to case reports or small series. In this report, we describe our experience in ICD lead extraction by intravascular countertraction method using Cook's extraction kit. A total of 47 high-voltage (HV) leads, 3 rate sensing (S) leads, and 2 subcutaneous arrays were removed from 42 patients (33 men, 9 women; mean age 59 years [range 14 to 81]). One HV superior vena cava (SVC) lead and 11 HV right ventricular (RV) leads were explanted by manual traction only and defined in the "lead removal" category. One S lead was removed using a femoral venous approach. The remaining 37 leads were explanted by SVC approach using extraction sheaths and defined in the "lead extraction" category. Twenty leads were extracted for "infectious" (group A) and 17 leads for "noninfectious" (group B) etiologies for which extraction times of 27.0+/-18.0 and 27.0+/-15.0 minutes (mean+/-SD), respectively, were not different. Although extraction time, 34.0+/-11.0 minutes, for leads implanted for >48 months was longer than 23.0+/-16.0, 28.0+/-18.0, and 24.0+/-14.0 minutes, for leads with implant durations of 12, 24, and 48 months, respectively, such differences were not statistically significant. The extraction time, however, was directly related to the degree of fibrosis around the lead, 39.0+/-15.0 minutes for leads with severe fibrosis compared with 13.0+/-6.0 minutes for the leads with mild fibrosis (p<0.001). Patient's age, sex, or history of coronary artery bypass graft surgery did not significantly affect extraction time. All except the initial 2 lead extractions were performed in the electrophysiology laboratory. No mortality or serious complications associated with the procedure using these methods were observed.

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Ablation of intra-atrial reentrant tachycardia following Mustard or Senning procedures has low success rates. The Biosense Carto system was used to map intra-atrial reentry in a 22-year-old woman who had undergone a Mustard procedure. A line of block was created connecting a Mustard baffle suture line to the tricuspid valve annulus, which terminated the arrhythmia and prevented its reinitiation. Multisite electroanatomic mapping was invaluable in defining atrial anatomy and the intra-atrial reentrant pathway, and in creating a contiguous line of block. This mapping may improve ablation success rates in patients following the Mustard or Senning repair.

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The North Boundary Containment System (NBCS), an intercept-and-treat system, was established at Rocky Mountain Arsenal (RMA), Commerce City, CO, to remove low-level organic contaminants from a groundwater plume exiting RMA to the north and northwest. N-nitrosodimethylamine (NDMA) was detected in groundwater collected from the dewatering and recharge zones of the NBCS system. Concern over the fate of NDMA, in terms of potentially exiting the boundaries of the arsenal, prompted an investigation to evaluate potential attenuation mechanisms for NDMA within the alluvial aquifer system and within the NBCS itself. Groundwater, soil, and granular activated carbon (GAC) samples were taken from key locations in the NBCS system. Soil and GAC samples were assayed for sorption kinetics and for adsorption and desorption properties using 14C-labeled NDMA. NDMA biodegradation experiments were conducted by following 14CO(2) evolution from 14C-labeled NDMA in soils and GAC samples under aerobic and anaerobic conditions. The sorptive capacity of the site soils for NDMA was insignificant. Furthermore, the adsorption of the NDMA by the soil was almost completely reversible. Evaluation of the degradation potential of the native microbial consortia indicated a high level of NDMA mineralization when measured using bench-scale microcosms. The native consortia had capability to mineralize the NDMA under both aerobic and anaerobic incubations, indicating facultative characteristics. Testing of the local groundwater chemistry revealed that the area of the aquifer of interest was microaerobic and neutral in pH. These conditions were optimal for NDMA removal. While sorption was insignificant, degradation was a significant attenuation mechanism, which may be the reason that no NDMA has migrated off-site. This gives rise to the potential of a long-term sink for attenuating NDMA within the recharge zone of the treatment system.

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Cardiovascular disease is the leading cause of illness and death in the United States. Clinical data continue to support primary prevention through the aggressive treatment of well-defined cardiovascular risk factors. Three risk factors that can be modified to lower the risk of cardiovascular disease and death are hypercholesterolemia, hypertension, and cigarette smoking. Even patients with asymptomatic cardiovascular disease have been shown to benefit from aggressive cholesterol-lowering therapy. New JNC-VI guidelines for managing hypertensive disease recommend that treatment decisions be based on level of blood pressure plus presence or absence of target organ damage or other risk factors. The risk of myocardial infarction in former smokers approaches that of nonsmokers after 3 years.

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A review of 2003 consecutive amniocenteses performed in late pregnancy under ultrasonic control is presented. No perinatal mortality was encountered. On this evidence the method described is suggested to be the safest available for obtaining liquor in late pregnancy.

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A case of spontaneous epidural abscess occuring in a pregnant woman is reported. Some delay in diagnosis occurred. Decompression resulted in prompt recovery and improvement of a mild neurological deficit.

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Norvedan (2-phenyl-4-p-chlorophenyl-thiazole-5-ylacetic acid) has been investigated for anti-inflammatory activity using an 'adjuvant arthirits' in rats and for analgesic activity using a writhing test in mice and a pressure test in rats. At oral doses of 10, 30 and 100 mg/kg Norvedan caused a dose-related inhibition of the primary swelling of the paw injected with adjuvant and the development of secondary lesions was also inhibited. Writhing induced in mice by i.p. administered acetic acid was also reduced by Norvedan at oral doses of 30 mg/kg and above and the response was related to dose. Against pain induced in rats by application of pressure to an inflamed paw Norvedan alsp showed good activity which was present for at least 6 hr after dosing.

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Two hundred consecutive amniocenteses for lecithin/sphingomyelin (L/S) determination in late pregnancy are reviewed. These procedures were performed under ultrasonic control before induction of labor or elective cesarean section in a prospective study to determine a safe method for aminocentesis. Complications included 3 failures, 14 blood-stained samples, 2 cases of labor occuring within 24 hours after amniocentesis, and 1 maternal abdominal wall hematoma. There was no cases of perinatal morbidity or mortality. It is proposed that this is a safe method of abdominal amniocentesis for L/S determination in late pregnancy.

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