Infective endocarditis in a patient with Williams' syndrome--case report

An 18-year-old male was admitted to Seoul National University Hospital for the evaluation of fever and chill on February 3, 1988.

On physical examination, his face showed a characteristic “elfin” facial appearance. His face was characterized by abnormalities of dental development, a broad overhanging upper lip, high arched palate and gum hypertrophy. He also showed mental retardation.

Cardiac catheterization with selective cineangiocardiography demonstrated a supravalvular aortic narrowing, grade 2 aortic insufficiency, and moderately dilated proximal coronary arteries with normal distribution without an intraluminal narrowing. There was a systolic pressure gradient (55mmHg) between the aortic root and ascending aorta distal to a stenotic segment.

MRI showed a supravalvular aortic stenosis.

Vegetation was not found on echocardiograpghy. Unidentified G(−) rods were isolated in 3 out of 9 bottles in blood culture test.

He was treated with Na-penicillin and gentamicin for 28 days.

Cardiac amyloidosis diagnosed by endomyocardial biopsy

A 56-year-old male patient who had a history of syncopal attack was diagnosed as having cardiac amyloidosis. His ECG finding showed a pattern of inferior and anteroseptal wall infarction with Wenckebach AV block.

Echocardiographic examination revealed that the LV posterior wall and interventricular septum were markedly thickened with granular sparkling.

We demonstrated the amyloid deposit in the myocardium by endomyocardial biopsy.

Pathology showed a green white birefringence by polarizing illumination and amyloid fibril in electron microscopic study.

1,2,4-Trioxanes as potential antimalarial agents

A number of 1,2,4-trioxanes were prepared and tested for antimalarial activity in search of a simplified analogue of the naturally occurring antimalarial qinghaosu. The compounds were assayed in an in vitro system for antimalarial activity against chloroquine-susceptible and chloroquine-resistant strains of Plasmodium falciparum. The most active compounds were methyl 2-(2,4a-epidioxy-4a,5,6,7,8,8a-hexahydro-5,5,8a-trimethyl-2H-1-benzop yra n-2-yl) acetate (3b), which showed IC20's of 96 and 39 ng/mL, respectively, and 2,4a-epidioxy-3,4,4a,5,6,7,8,8a-octahydro-2-[2-(benzoyloxy)propyl]-5,5,8 a- trimethyl-2H-1-benzopyran (12), which showed IC50's of 24 and 99 ng/mL, respectively. For comparison, qinghaosu exhibits an IC50 of 1 ng/mL for both strains.

Noninvasive evaluation of left ventricular diastolic function in patients with angina pectoris--pulsed Doppler echocardiographic technique

To assess the disturbed left ventricular diastolic filling by pulsed Doppler echocardiography in patients with angina pectoris who have normal systolic function, 55 subjects (33 angina patients with, 22 control subjects without significant (⩾75%) coronary artery narrowing) underwent pulsed Doppler echocardiography examination one day before coronary arteriography. From analysis of the transmitral flow velocity curve, diastolic time intervals, peak early and late atrial flow velocities, the ratio of early to atrial peak flow velocity, and deceleration slope after peak early flow velocity were measured. The angina group had a significantly higher peak atrial flow velocity (50.1 ± 10.0 cm/sec vs. 43.7 ± 9.0, p<0.05) and a lower ratio of early to atrial peak flow velocity (0.91 ± 0.24 vs. 1.17 ± 0.30, p<0.005), but peak early flow velocity, deceleration slope, and diastolic time intervals were similar in both groups. Therefore, the pulsed Doppler technique using the transmitral flow velocity curve is thought to be useful in the noninvasive evaluation of diastolic function even in patients with angina pectoris who have normal systolic function and no left ventricular hypertrophy.

Enhancement of accuracy in OTF measurement

A knife-edge scanning method was developed to enhance the accuracy in OTF measurement. A slit image formed by the lens under test was scanned by a knife-edge which was moved by a stepping motor. It was possible to increase the signal-to-noise ratio with averaging 4-32 data at each point through a scan. The standard deviation was decreased to under 0.25% in the MTF unit.

Percutaneous pulmonary valvuloplasty with a double-balloon technique

Percutaneous pulmonary valvuloplasty with a double-balloon technique was used in eight patients, aged 10-40 years, in whom valvuloplasty with a single 20-mm balloon resulted in inadequate dilatation of the stenosis. The diameters of the additional balloon varied from 10 to 20 mm. Balloons were inflated manually at about 30-45 psi (206.7-310.1 kPa) and deflated immediately after disappearance of the balloon waist. The mean peak systolic pressure gradient was 85 mm Hg +/- 37 before valvuloplasty, and it decreased to 38 mm Hg +/- 28 afterward (P less than .05). Double-balloon dilation and simultaneous computed tomography were done in two cardiac specimens from adult cadavers. At inflations at 30 and 45 psi (206.7 and 310.1 kPa), the outflow tract was elongated, and the balloons also deformed into ovoid shape at the lower pressure. The double-balloon technique appears to be safe and effective for relief of pulmonary valvular stenosis in those cases in which single-balloon technique is inadequate, especially in older children and adults.

Endoperoxides as potential antimalarial agents

A number of mono- and bicyclic endoperoxides were prepared and tested for antimalarial activity in search of a simplified analogue of the 5-oxygen-substituted 1,2,4-trioxane ring structure of the naturally occurring antimalarial qinghaosu. The compounds were assayed in an in vitro system for antimalarial activity against chloroquine-susceptible and chloroquine-resistant strains of P. falciparum. The most active compound in this assay was 2-[((butyloxy)-carbonyl)oxy]-1,1,10-trimethyl-6,9-epidioxy-delta 7-octalin (17a), which showed an IC50 of 100 and 57 ng/mL, respectively. For comparison, qinghaosu exhibits a mean IC50 less than 3.4 ng/mL.

Advanced gastric carcinoma chemotherapy with cisplatin, mitomycin C, BCNU, and 5-fluorouracil in combination

Forty patients with advanced gastric carcinoma were treated with mitomycin C, BCNU, cisplatin, and 5-fluorouracil in combination. Mitomycin C 6 mg per sq m was given by i.v. on day 1, BCNU 60 mg per sq m was given by i.v. on day 2, cisplatin 60 mg per sq m was given by 3 hour i.v. infusion with mannitol diuresis on day 3, and 5-fluorouracil 300 mg per sq m was given by i.v. infusion on days 4, 5, and 6. Each course of the polychemotherapy was repeated every 35 days. Two patients failed to return for follow-up, thus 38 patients were available for response evaluation of this regimen. Of the 38 patients, 25 (66%) achieved partial remission. The median duration of response was 20 weeks. Survival time was not measured. Significant bone marrow toxicities were not encountered. The major toxic side effects were gastrointestinal: anorexia, nausea and/or vomitings. Clinically significant ototoxicity or nephrotoxicity was not experienced. One patient developed a mild peripheral neuropathy. This four-drug polychemotherapy regimen appears to have substantial activity agaist advanced gastric carcinoma.

A case report of tracheobronchitis by herpes simplex virus, type I

Herpes simplex virus (HSV) infection of the lung and lower respiratory tract has been thought to be a rare and fatal disease, usually in patients with immunosuppression, severe burns, or prolonged intubation. However, recently, increasing numbers of patients have been reported to have a localized infection and some of them have recovered without specific therapy.

In Korea, there has been yet no proven case of HSV infection of the lower respiratory tract. Recently, we saw a case of localized HSV infection of the tracheobronchus. A 78-year-old male patient was admitted in acute respiratory failure, with COPD and old pulmonary trberculosis. After the clinical condition improved, a bronchoscopy was done which revealed a localized area of swelling, hyperemia, and mucosal irregularity at the lower trachea and right upper lobar bronchus. Bronchial brushing and biopsy showed typical cytologic changes including intranuclear inclusion body. Viral culture of a bronchial washing revealed a growth of HSV, type I. The patient died of unrelated, acute myocardial linfarction.

Trichothecenes produced by Stachybotrys atra from Eastern Europe

A total of 17 isolates of Stachybotrys atra isolated from various parts of Hungary and Czechoslovakia were grown on rice, and the toxin production of each isolate was analyzed by high-performance liquid chromatography. Of the 17 isolates, 14 produced macrocyclic trichothecenes (satratoxins F, G, and H, roridin E, and verrucarin J) as well as trichoverrols A and B. Most isolates produced satratoxins G and H in higher quantities than the other trichothecenes. The yield (in milligrams) of trichothecenes produced by one isolate grown on 800 g of rice was as follows: roridin E, 12; satratoxin F, 10; satratoxin G, 75; satratoxin H, 100; trichoverrol A, 15; and trichoverrol B, 30.

Tumour uptake of radiolabelled pyrimidine bases and pyrimidine nucleosides in animal models. IX. Radiolabelled 1-(2'-fluoro-2'-deoxy-beta-D-ribofuranosyl)uracil and 1-(2'-chloro-2'-deoxy-beta-D-ribofuranosyl)uracil

The biodistribution of radiolabelled 1-(2'-fluoro-2'-deoxy-beta-D-ribofuranosyl)uracil (2'-FUdR) and 1-(2'-chloro-2'-deoxy-beta-D-ribofuranosyl)uracil (2'-ClUdR) was evaluated using in-vivo and in-vitro tumour models. 6-[3H]-2'-FUdR exhibited a maximum tumour:blood (T:B) ratio (Walker 256 carcinosarcoma) of 1.0 at 15 min after injection whereas 2-[14C]-2'-FUdR and 2'-[36Cl]-2'-ClUdR exhibited maximum T:B ratios (Lewis lung carcinoma) of 3.0 and 4.1 respectively at 120 min. Clearance of blood radioactivity after injection of 6-[3H]-2'-FUdR, 2-[14C]-2'-FUdR and 2'-[36Cl]-2'-ClUdR was rapid and best described by a biexponential function. The clearance half-lives of the short-lived components were calculated as 1.6 min (95.5%), 2.3 min (94.7%) and 1.2 min (96.0%) respectively. The clearance half-lives of the long-lived components were 23 h (4.5%) for 6-[3H]-2'-FUdR, 89 min (5.3%) for 2-[14C]-2'-FUdR, and 49 min (4.0%) for 2'-[36Cl]-2'-ClUdR. Less than 36% of the 14C radioactivity present in the urine 2 h after injection of 2-[14C]-2'-FUdR was associated with 2'-FUdR, whereas greater than 91% of the 36Cl radioactivity in the urine 2 h after injection of 2'-[36Cl]-2'-ClUdR was associated with 2'-ClUdR. Both 6-[3H]-2'-FUdR (less than 3.1 pmol/10(6) cells) and 6-[3H]-2'-ClUdR (1.0 +/- 0.2 pmol/10(6) cells) were incorporated into cultured Raji tumour cells in vitro to a lesser extent than the natural nucleosides uridine (137.2 +/- 3.8 pmol/10(6) cells) and 2'-deoxyuridine (23.5 +/- 2.5 pmol/10(6) cells) after a 20 min incubation.

7 alpha-hydroxytrichodermol, a new trichothecene from Myrothecium roridum

Five plant-pathogenic isolates of Myrothecium roridum from Florida produced only simple trichothecenes rather than the usual macrocyclic trichothecenes. The major metabolite was 7 alpha-hydroxytrichodermol.

TDP-1, a toxic component causing tibial dyschondroplasia in broiler chickens, and trichothecenes from Fusarium roseum 'Graminearum'

Fusarium roseum 'Graminearum' was isolated from overwintered oats in Alaska and was tested for its ability to cause tibial dyschondroplasia (TDP) in broiler chickens. The water-soluble fraction was tested and found to cause TDP. In addition, diacetoxyscirpenol and 7-hydroxydiacetoxyscirpenol were identified in the acetonitrile fraction of the extracts and caused mild mouth lesions in chickens. Six major water-soluble components were purified by thin-layer chromatography and tested for toxicity to chick embryos. One of the six components, called TDP-1, was found to be lethal to chick embryos. There was a 100% incidence of TDP in chickens fed a diet containing 75 ppm (wt/wt) of pure TDP-1, thus establishing the cause and effect relationship between TDP and TDP-1. Analyses by thin-layer chromatography and mass spectrometry revealed that TDP-1 is polar and ninhydrin positive, exhibits fluorescence with UV irradiation, and is a nitrogen-containing component with an empirical formula of C15H20N2O4.

The effect of a purified water-soluble fraction of a Fusarium roseum 'Graminearum' culture on reproduction of white Leghorn females

White Leghorn females (36 weeks old) in egg production were individually fed a purified water-soluble fraction residue remaining from the water extract and a crude culture of Fusarium roseum 'Graminearium'. Each fraction was fed at 3% of the diet for 6 weeks followed by 2 weeks with a control diet. Hens were inseminated weekly with .05 ml of pooled semen from males given control diets. The purified water-soluble fraction increased feed consumption during the test periods. During the posttest period, hens fed test diets consumed less feed than those fed a control diet. All test diets did not affect body weight change during the test periods. There was a significant increase in body weight of hens on the diet containing 3% crude culture and a marked decrease in body weight of hens fed the purified water-soluble fraction during the posttest period. Egg production and egg weight were not affected by treatments during the test and posttest periods. Fertility was reduced by the crude culture of F. roseum 'Graminearum' during the 6-week test. Hatchability of fertile eggs was significantly reduced by the purified water-soluble fraction and the crude culture of F. roseum 'Graminearum'. Hatchability rapidly increased when these toxic diets were replaced with control diets. The majority of embryo mortality occurred during 5 days of incubation. The major mycotoxins responsible for reduced hatchability of fertile eggs appeared to be water soluble components of F. roseum 'Graminearum' and not trichothecenes or zearalenone.

Tumor uptake of radiolabelled pyrimidine bases and pyrimidine nucleosides in animal models--VIII. Synthesis and tissue distribution of N-[2-(hydroxyethoxy) methyl]-5-[3H]methyluracil

The tritium-labelled acyclonucleoside, N-[2-(hydroxyethoxy)methyl]-5-[3H]methyluracil (3H-3), was synthesized for evaluation as a tumor diagnostic agent. 5-[3H]-Methyluracil, 3H-1, was converted to the 2,4-bis-trimethylsilyl intermediate which was coupled with 2-acetoxyethoxymethyl bromide to afford 1-[(2-acetoxyethoxy)methyl-5-[3H]methyluracil (3H-2). Treatment of 3H-2 with sodium methoxide in methanol afforded 3H-3 (specific activity 188 MBq mmol-1. The tissue distribution of 3H-3 was examined in male BDF1 mice bearing Lewis Lung (LL) carcinomas. Long bone exhibited the highest tumor: tissue ratios. The kidney contained the highest radioactivity level relative to the tumor. This suggested a major urinary route of excretion. The major radioactive blood component (89.21%) was found to have a biological half-life of 0.19 min. The title compound is unsuitable for use as a diagnostic agent for LL carcinoma because of low tumor uptake and rapid urinary elimination of injected radioactivity from the body.

Tumor uptake of radiolabelled pyrimidine bases and pyrimidine nucleosides in animal models: VII. [2-14C]-5-ethyl-1-(2'-deoxy-beta-D-ribofuranosyl)uracil

The differential tissue uptake and blood clearance of [2-14C]-5-ethyl-1-(2'-deoxy-beta-D-ribofuranosyl)uracil [2-14C]-5-EtUdR) in BDF1 mice bearing Lewis Lung carcinomas has been investigated. The kidney, gall bladder with contents and GIT exhibited the greatest concentration of radioactivity relative to the tumor up to 30 min after i.v. injection of [2-14C]-5-EtUdR. Blood, spleen, liver and muscle exhibited a lower concentration of radioactivity than the former group. Radioactivity levels in the stomach and skin were similar to that of the tumor. The long bone had the lowest radioactivity level of all the tissues examined. During the 1-3 h period following injection, the tumor contained more radioactivity than most other tissues with the exception of the gall bladder and contents, GIT and kidney. Packed erythrocytes contained 62-78% of the radioactivity in the whole blood. Clearance of injected radioactivity from whole blood followed two-compartment kinetics. Elimination was mainly renal, although some biliary excretion of injected radioactivity was also observed.

The synthesis of [36Cl]-, [82Br]- and [123I]-labelled 1-(3'-chloro-(bromo and iodo)-3'-deoxy-beta-D-arabinofuranosyl)uracil

Reaction of the epoxy nucleoside 1-(2',3'-epoxy-beta-D-lyxofuranosyl)uracil (1) with [36Cl]HCl afforded [36Cl]-1-(3'-chloro-3'-deoxy-beta-D-arabinofuranosyl)uracil (2a) with a specific activity of 5.48 MBq mmol-1. A similar reaction of 1 with [82Br]NH4Br yielded [82Br]-1-(3'-bromo-3'-deoxy-beta-D-arabinofuranosyl)uracil (2b) with a specific activity of 29 MBq mmol-1. Alternatively neutron activation of the preformed [81Br]-1-(3'-bromo-3'-deoxy-beta-D-arabinofuranosyl)uracil (2b) gave low yields of the [82Br)-labelled 2b with a specific activity of 8.99 MBq mmol-1. [123I]-1-(3'-Iodo-3'-deoxy-beta-D-arabinofuranosyl)uracil (2c) was similarly prepared with a specific activity of 125 GBq mmol-1 by the reaction of [123I]HI with the epoxide. These compounds were prepared for evaluation as non-invasive tumor imaging radiopharmaceuticals.

Tumor uptake of radiolabelled pyrimidine bases and pyrimidine nucleosides in animal models: VI. 1-(3'-[36Cl]-chloro-, 1-(3'-[82Br]-bromo- and 1-(3'-[123I]-Iodo-3'-deoxy-beta-D-arabinofuranosyl)uracil

3'-Radiohalogenated (36Cl, 82Br and 123I) "arabino" pyrimidine nucleosides were evaluated as potential tumor diagnostic agents in tumor bearing animals. No preferential tissue uptake was observed. The compounds were excreted mainly unchanged in the urine. The 3'-[36Cl]- and 3'-[82Br]-3'-deoxyarabino nucleosides exhibited biliary uptake. The low uptake of injected radioactivity by the tumor was probably due to the combined effects of the lack of a C-3' hydroxyl group in the "ribo" configuration, the presence of a halogen, the structural rigidity imposed by the presence of a halogen and the short biological half-lives of the compounds.

Production of Nivalenol and Fusarenone-X by Fusarium tricinctum Fn-2B on a Rice Substrate

Fusarium tricinctum Fn-2B was grown on a rice substrate at room temperature (22 to 26°C) for 2 weeks followed by growth at a low temperature (10 to 12°C) for an additional 2 weeks. A total of 1.5 g of nivalenol and 80 mg of fusarenone-X were obtained from 2 kg of rice culture. The methods of production, extraction, and purification are described.

The effect of a Fusarium roseum culture and diacetoxyscirpenol on reproduction of White Leghorn females

White Leghorn females in egg production (36 weeks old) were fed a culture of Fusarium roseum containing 15 ppm diacetoxyscirpenol (DAS) and other unidentified toxins at culture levels of 0, 1, and 2% of the diet for 8 weeks. Following this, all hens were placed on control (0% toxins) feed for 6 weeks. Birds were inseminated weekly with .05 ml of pooled semen from males given normal diets. The F. roseum had no significant effect on body weight change or egg weights. During the initial 8 weeks, egg production was significantly depressed by both the 1 and 2% levels whereas feed consumption, fertility, and hatchability of fertile eggs was reduced only by the 2% level of F. roseum. Moreover, the majority of embryo mortality occurred prior to the 7th day of incubation. All production levels returned to normal when the toxins were removed during the final 6 weeks. In a second experiment, control (0%), .5 ppm purified DAS, and 3% F. roseum culture were fed to White Leghorn females (50 weeks old) for 4 weeks followed by a 2-week withdrawal period when all birds were given control diets. In 4 weeks, hatchability of fertile eggs was reduced 24% by DAS and 99% by the culture of F. roseum but returned to normal after the toxins were removed. Other production indices were unaffected by dietary treatment. The DAS appears to be only partially responsible for the reduced hatchability; the major toxicant has not been identified.

Quantitative conformation of dimethoate residues in wheat plants by single ion mass spectrometry

A gas chromatographic-single ion mass spectrometric method was developed for determining dimethoate residues in wheat plants. The base peak (m/e 37) of dimethoate was chosen as the single ion peak, and methyl stearate was used as an internal standard for this analysis. The minimum detectable concentration of dimethoate by this method was about 0.1 ppm for a 20 g wheat plant sample. The recoveries of dimethoate were about 89% at 0.13 ppm and greater than 96% at 0.5-1 ppm.

Amphetamine metabolism in mice exposed chronically to phenobarbital and to phenobarbital with carbon tetrachloride

The metabolism of amphetamine was studied in three groups of mice, including normal mice (N), mice given chronic doses of phenobarbital via their drinking water (PB), and mice exposed to carbon tetrachloride vapors daily during the course of chronic phenobarbital consumption (PB/CCl4). Renal and hepatic tissue from animals of each group were examined by electron microscopy. Mice in the PB/CCl4 group demonstrated the classical symptoms of carbon tetrachloride-induced hepatic cirrhosis, and structural damage to the kidney. The PB group presented a normal renal pathology, but ultrastructural changes including swollen mitochondria and dilation of the endoplasmic reticulum were evident in the hepatocytes. The N, PB and PB/CCl4 mice excreted 84.5, 61.5 and 72.3 percent respectively of a dose of 14C-amphetamine sulfate in the 0-72 hour urine. Seven major urinary metabolites were detected in the normal group, 4 in PB group, and 3 in the PB/CCl4 group. Unchanged amphetamine, rho-hydroxyamphetamine and benzoic acid were tentatively identified by combined techniques of gas chromatography and thin-layer chromatography with autoradiography.

Rapid improvement in nerve conduction velocity following renal transplantation

In 12 patients with chronic renal failure who received kidney transplants from either cadavers (6) or related living donors (6), rapid improvement in median sensory and motor nerve conduction velocities (NCVs) was observed within a few days after transplantation. The postoperative improvement in median sensory NCV was found to bear a statistically significant negative correlation with creatinine and myo-inositol concentrations. We suggest that metabolic phenomena are responsible for the rapid improvement in median sensory NCV following renal transplantation. The close relationship between myo-inositol and the median sensory NCV following transplantation suggests that elevated plasma myo-inositol concentrations may be related to nerve conduction abnormalities in uremic polyneuropathy.

Gas-liqiid chromatographic determination of pydrin, a synthetic pyrethroid, in cabbage and lettuce

Pydrin, alpha-cyano-3-phenoxybenzyl 2-(4-chlorophenyl)-3-methylbutyrate, a synthetic pyrethroid ester, is extracted from vegetables with acetonitrile, partitioned into petroleum ether before cleanup on a Florisil column, and analyzed by electron capture gas-liquid chromatography. Recoveries of 88-102% at 0.01 ppm, 99-102% at 0.1 ppm, and 98-104% at 1.0 ppm were obtained from fortified cabbage and lettuce samples. The method appears applicable to detection of the residues of Pydrin in the foliage of many types of crops.

Angiographic evidence of myocardial squeezing accompanying tachyarrhythmia as a possible cause of myocardial infarction

The coronary arteriogram of a 52-year-old man with Basedow's disease and who was suffering from myocardial infarction following rapid atrial fibrillation, showed severe myocardial squeezing without organic stenosis. Angiographically, the functional obstructive lesion was always observed both at systole and diastole during atrial pacing, 150 beats per minute, and suggests that myocardial squeezing may be the cause of myocardial infarction following tachyarrhythmia.

Squamous cell carcinoma of the tongue in a nine year renal transplant survivor: a case report with a discussion of the risk of development of epithelial carcinomas in renal transplant survivors

A case of squamous cell carcinoma of the tongue in a 26-year-old man developing nine years after renal transplantation is presented. This is the first such case to be reported. Within seven months, widespread tumor metastases resulted in death. Pathologic examination of the transplanted kidney demonstrated neither re-establishment of glomerulonephritis nor evidence of rejection, and lack of significant renal disease was confirmed by electron microscopy. This long term survival without development of renal pathology is also of great interest.

Eaton-Lambert syndrome: reflex improvement with guanidine

A 46-year-old man with typical clinical and electrophysiologic findings of the Eaton-Lambert syndrome did not have muscle stretch or H reflexes. With guanidine treatment (42.0 mg/kg/day), all of the tested muscle stretch reflexes except the right knee and the ankle jerks were improved and the H reflex on the left calf muscle was obtained. Latency of this response was normal but amplitude was decreased. The patient's clinical status was also improved. We suggest the basic defect at the neuromuscular junction in this syndrome as the most likely explanation for hypo- and a-reflexia.

Gas-liquid chromatographic determination of technical chlordane residues in food crops: interpretation of analytical data

An interlaboratory investigation of technical chlordane residues in food crops was carried out to determine the most practical and consistent method of reporting results. Using a technical chlordane reference standard, 8 gas chromatographic stationary phases were studied for their resolution capabilities. The best separations were obtained with SE-30 and its OV-1 equivalent. Using these columns and electron capture detection, potatoes and carrots from supervised field experiments were analyzed in duplicate and quantitated by using 4 methods of calculation. The data were statistically treated to determine the precision and bias for each method. Also, 1 sample was analyzed in duplicate on 2 different occasions by 6 laboratories to substantiate the initial conclusions. Based on the criterion of high precision it is suggested that a comparison of total area under the chromatogram of the sample with total area of standard technical chlordane be the method of quantitation. Only peaks which are common to both standard and sample have any significance in this type of calculation.