Biomedical subjects

J L Hubbard

Publications and source records attributed to J L Hubbard.

At least 19 recordsLinked to original sources

PubMed2001

Role of stereochemistry in N-(3,5-dichlorophenyl)-2-hydroxysuccinamic acid (2-NDHSA) nephrotoxicity.

The nephrotoxicity induced by the agricultural fungicide N-(3,5-dichlorophenyl)succinimide (NDPS) is mediated through oxidative metabolites of NDPS. Oxidation of the succinimide ring in NDPS yields the nephrotoxic metabolites N-(3,5-dichlorophenyl)-2-hydroxysuccinimide (NDHS) and its hydrolysis product N-(3,5-dichlorophenyl)-2-hydroxysuccinamic acid (2-NDHSA). The oxidation of NDPS on the succinimide ring also introduces an asymmetric carbon atom into these NDPS metabolites, so that R- and S- enantiomers of NDHS and 2-NDHSA are possible. The purpose of this study was to begin to explore the importance of the stereochemical orientation at the asymmetric carbon atom for the nephrotoxicity induced by NDPS metabolites. Male Fischer 344 rats were administered a single intraperitoneal (ip) injection of R-(+)- or S-(-)-2-NDHSA (0.05, 0.1 or 2.0 mmol/kg) or vehicle, and renal function was monitored for 48 h. R-2-NDHSA (0.1 mmol/kg) administration had little effect on renal function. R-2-NDHSA (0.2 mmol/kg) treatment induced mild diuresis on day 1, increased proteinuria, and a small increase in blood urea nitrogen (BUN) concentration, but no change in kidney weight or glucosuria. S-2-NDHSA (0.1 mmol/kg) induced marked nephrotoxicity as evidenced by diuresis on both post-treatment days, increased proteinuria, glucosuria, and increased kidney weight and BUN concentration. No evidence of hepatotoxicity was obtained in any treated group. Thus, the S-isomer of 2-NDHSA is a more potent nephrotoxicant than the R-isomer, and stereochemistry may play a role in NDPS metabolite-induced nephrotoxicity.

Animals↗

PubMed2001

First direct structural comparison of complexes of the same metal fragment to ketenes in both C,C- and C,O-bonding modes.

Using a series of Ir(I) and Rh(I) ketene complexes, conclusions about the structure and bonding of complexes of the fundamentally important ketene ligand class are reached. In a unique comparison of X-ray structures of the same metal fragment to ketenes in both the eta(2)-(C,C) and the eta(2)-(C,O) binding mode, the Ir-Cl bond distances in complexes of trans-Cl(Ir)[P(i-Pr)(3)](2) to phenylketene [4, eta(2)-(C,C)] and diphenylketene [2a, eta(2)-(C,O)] are 2.371(3) and 2.285(2) A, respectively. This would be consistent with greater trans influence of a ketene ligand bound to a metal through its C=C bond than one connected by its C=O bond. Back-bonding of Ir(I) and Rh(I) to diphenylketene was assessed using trans-Cl(M)[P(i-Pr)(3)](2)[eta(2)-(C,O)-diphenylketene] (2a and 2d). Most bond lengths and angles are identical, but slightly greater back-bonding by Ir(I) is suggested by the somewhat greater deformation of the ketene C=C=O system [C-C-O angles are 136.6(4) and 138.9(4) in the Ir and Rh cases 2a and 2d, respectively]. Syntheses of new labeled ketenes Ph(2)C=(13)C=O and Ph(2)C=C=(18)O and their Ir(I) and Rh(I) complexes are reported, along with the generation of an Ir(I) complex of PhCH=(13)C=O. The effects of isotopic substitution on infrared absorption data for ketene complexes are presented for the first time. Preliminary normal coordinate mode analysis allowed definitive assignment of absorptions ascribed to the C-O stretching frequencies of coordinated ketenes, which are near the absorptions for aromatic ring systems commonly found as substituents on ketenes. For free diphenylketene and four of its complexes and a phenylketene complex characterized by X-ray diffraction, the magnitude of the (13)C-(13)C coupling between the two ketene carbons is correlated to carbon-carbon bond distance.

Journal Article↗

PubMed2001

Body composition and energy balance: lack of effect of short-term hormone replacement in postmenopausal women.

Postmenopausal women (PMW) commonly believe that hormone replacement (HR) leads to weight gain, and fear of weight gain and/or an actual increase in weight is one of the principle reasons evoked for the discontinuation of HR. However, the potential effects of physiologic HR on body composition have yet to be separated from the effects of lifestyle or aging. Therefore, we examined the effect of short-term hormone replacement and age on alterations in weight, body composition, and energy balance. A prospective study of 28 healthy PMW aged 45 to 55 years (younger PMW, studies completed n = 18) and 70 to 80 years (older PMW, studies completed n = 15) was conducted. The last menstrual period was more than 12 months previously. The women had a body mass index (BMI) less than 30 kg/m(2) and were taking no medication. Subjects were studied at baseline, after 1 month of transdermal estrogen (Estraderm, 50 microg/day) administration (E2), followed by a further month of transdermal estrogen with progesterone (100 mg per vagina twice daily) for the final 7 days (E2 + P). Anthropometric measurements and energy assessments were performed at each visit. Physiologic HR was achieved in each subject, and there was no difference between levels achieved in older and younger women. Resting energy expenditure and activity level were positively correlated with fat-free mass (P <.0001), while energy intake was not. Resting energy expenditure was lower in older compared with younger PMW when adjusted for fat-free mass (P <.005). Energy intake was also lower in the older PMW when corrected for fat-free mass (P <.0001); as was activity level (P <.05). There was no effect of hormonal treatment on any of the parameters measured. Changes in weight from baseline for E2 (0.37 +/- 0.25 and 0.61 +/- 0.27 kg in younger and older) and E2 + P (0.11 +/- 0.38 and 0.28 +/- 0.31 kg) were not statistically significant. In addition, there was no difference in BMI, fat mass, fat-free mass, total body water, or waist-to-hip ratio (WHR) between groups or with hormonal treatment. In conclusion, short-term transdermal HR is not associated with significant changes in weight or other anthropometric measures in younger or older PMW. These studies confirm the decrease in energy expenditure that occurs with aging, but indicates that there is no effect of HR on resting energy expenditure.

Aged↗

PubMed2000

Synthesis and structures of heterocyclic azidogallanes [(CH3)ClGaN3]4 and [(CH3)BrGaN3]3 en route to [(CH3)HGaN3]x: an inorganic precursor to GaN.

The synthesis of [(CH3)ClGaN3]4 (1) with a heterocyclic cyclooctane-like structure and [(CH3)BrGaN3]3 (2) with a trimeric structure has been demonstrated. X-ray structural determinations reveal that 1 and 2 consist of Ga4N4 eight-membered rings and Ga3N3 six-membered rings, respectively, in which the Ga atoms are bridged by the alpha nitrogens of the azide groups. [(CH3)ClGaN3]4 crystallizes in the tetragonal space group P42(1)c with a = 11.017(4) A, c = 8.699(7) A, and Z = 8. [(CH3)BrGaN3]3 crystallizes in the triclinic space group P1 with a = 8.1080(10) A, b = 9.9390(13) A, c = 10.4439(13) A, alpha = 86.069(3) degrees, beta = 86.771(3) degrees, gamma = 80.829(2) degrees, and Z = 6. The reaction of 1 and 2 with LiGaH4 yields [(CH3)HGaN3]x, which is a new low-temperature source of GaN.

Journal Article↗

PubMed2000

Studies of the synthesis and thermochemistry of coordinatively unsaturated chelate complexes (eta 5-C5Me5)IrL2 (L2 = TsNCH2CH2NTs, TsNCH2CO2, CO2CO2).

A comparative synthetic, structural, and thermochemical study on a series of chelate complexes containing the fragment (eta 5-C5Me5)Ir [(eta 5-C5Me5)Ir(TsNCH2CH2NTs) (1), (eta 5-C5Me5)Ir(TsNCH2CO2) (2), (eta 5-C5Me5)Ir(CO2CO2) (3)] was performed to clarify the roles of carboxylato and sulfonamido ligands. Whereas 1 and 2 are monomeric in solution and in the solid state, 3 appears to exist as an oligomer or polymer, (3)n, which can be broken up by addition of a ligand L such as a phosphine, CO, or 2-methoxypyridine to form (eta 5-C5Me5)Ir(L)(CO2CO2) (6). The synthesis of (3)n from [(eta 5-C5Me5)IrCl(mu-Cl)]2 required the use of silver oxalate in CH3CN, but if other solvents were used, the bridging oxalato complex (eta 5-C5Me5)IrCl(mu-eta 2-eta 2-C2O4)ClIr(eta 5-C5Me5) (7) was obtained and identified by X-ray diffraction. Enthalpies for reaction of THF-soluble monomers 1 and 2 with PMe3 were determined to be -28.7(0.5) and -28.5(0.4) kcal mol-1, respectively. The oligomerization behavior of 3 may be a result of reduced sigma- or pi-donation of carboxylato ligands compared to N-tosylamido ligands, because the values for nu CO in oxalato and bissulfonamido complexes 6-CO and (eta 5-C5Me5)Ir(CO)(TsNCH2CH2NTs) (4-CO) were 2064 and 2042 cm-1, respectively.

Journal Article↗

PubMed2000

Assessment of macronutrient and micronutrient intake in women with anorexia nervosa.

OBJECTIVE: The purpose of this study is to evaluate the accuracy of diet history compared to observed food intake in the nutritional assessment of women with anorexia nervosa (AN) and healthy age-matched controls. METHOD: One-month diet history was compared to 1-day observed food intake in 30 women with AN and 28 control subjects. RESULTS: Reported intake by diet history was similar to observed intake for macronutrient composition and fat intake for patients with AN. Reported energy intake was higher than observed intake (1,602 +/- 200 kcal vs. 1,289 +/- 150 kcal, p <.05), but was in agreement with predicted energy expenditure by the Harris-Benedict equation (1,594 +/- 18 kcal, p =.97) in patients with AN. Micronutrient intake by diet history was highly correlated with observed intake in patients with AN. More than one half of the patients with AN failed to meet the recommended dietary allowance (RDA) for vitamin D, calcium, folate, vitamin B12, zinc, magnesium, and copper when assessed by diet history. In contrast to patients with AN, diet history did not correlate with observed intake of energy, macronutrients, or most micronutrients among the controls. DISCUSSION: Diet history is an accurate tool to assess fat intake and macronutrient composition in patients with AN and demonstrates significant micronutrient deficiencies in this population. The agreement between total energy intake and predicted energy expenditure supports the overall utility of the diet history in the nutritional assessment of patients with AN.

Adolescent↗

PubMed1999

Nephrotoxic potential of N-(3,5-dichloro-4-fluorophenyl)succinimide in Fischer 344 rats: comparison with N-(3,4,5-trichlorophenyl)succinimide.

Numerous structure-nephrotoxicity relationship studies from our laboratory have demonstrated that N-(3,5-dichlorophenyl)succinimide (NDPS) is one of the most potent nephrotoxicants among the N-arylsuccinimides. The purpose of this study was to extend our previous structure-nephrotoxicity relationship studies by examining the effect of addition of a fluoro verses a chloro group at the 4-phenyl position in NDPS. Male Fischer 344 rats (four rats/group) received a single intraperitoneal (i.p.) injection of N-(3,5-dichloro-4-fluorophenyl)succinimide (NDCFPS) or N-(3,4,5-trichlorophenyl)succinimide (NTCPS)(0.4 or 0.8 mmol/kg) or vehicle, and renal function monitored at 24 and 48 h. NDCFPS did not induce significant nephrotoxicity at either dose tested. In contrast, NTCPS (0.4 or 0.8 mmol/kg) induced marked nephrotoxicity characterized by diuresis, increased proteinuria, glucosuria, elevated kidney weight and increased blood urea nitrogen (BUN) concentration. NTCPS also induced marked proximal tubular necrosis at both doses tested. Neither NDCFPS nor NTCPS induced hepatotoxicity at either dose tested. The results of these experiments indicate that addition of a fluoro group at the 4-position on the phenyl ring of NDPS produces a nonnephrotoxicant NDPS derivative (NDCFPS), while addition of a chloro group at this site produces an NDPS derivative with similar nephrotoxic potential to NDPS. The mechanism for this differential effect between 4-halophenyl substitution is unclear, but may result from increased hydrolysis of the succinimide ring and/or increased clearance of N-arylsuccinimide metabolites when a fluoro group is added to the 4-position of the phenyl ring.

Animals↗

PubMed1998

Report on a protocol for the active management of labor.

The authors review a protocol for the active management of labor, first developed by Kieran O'Driscoll, MB, and colleagues at the National Maternity Hospital in Dublin, Ireland, in 1969. This protocol is based on the principle that every pregnant woman would deliver within 12 hours of being admitted to the hospital. Although this approach to labor management has successfully reduced the number of cesarean sections performed in Dublin, Ireland, it has failed to do so in the United States, where active labor management has come under considerable criticism.

Clinical Protocols↗

PubMed1997

Hydatidiform mole.

Hydatidiform mole is a gestational trophoblastic disease that arises from fetal rather than maternal tissue and can become metastatic. Most signs and symptoms occur late in the first trimester and are often confused with symptoms of a normal pregnancy and, thus, are often disregarded. The two most important diagnostic tools to detect this disease are the ultrasound and the quantitative beta-human chorionic gonadotropin assay. Treatment includes dilation and evacuation of the uterus and strict follow-up of quantitative beta-human chorionic gonadotropin levels. It is also important that the patient be placed on a reliable form of birth control during her follow-up period.

Adolescent↗

PubMed1997

Couvelaire uterus.

Uteroplacental apoplexy is a rare but nonfatal complication of severe forms of placental abruption. It occurs when vascular damage within the placenta causes hemorrhaging that progresses to and infiltrates the wall of the uterus. It is a syndrome that can only be diagnosed by direct visualization or biopsy (or both). For this reason, its occurrence is perhaps underreported and underestimated in the literature. The subject of this report is a 24-year-old pregnant woman who had a placental abruption an in whom classic uteroplacental apoplexy was diagnosed at the time of her cesarean section.

Abdominal Pain↗

PubMed1996

Nephrotoxic potential of 2-amino-5-chlorophenol and 4-amino-3-chlorophenol in Fischer 344 rats: comparisons with 2- and 4-chloroaniline and 2- and 4-aminophenol.

Nephrotoxicity occurs following intraperitoneal (i.p.) administration of 2-chloroaniline or 4-chloroaniline hydrochloride to Fischer 344 rats, but the nephrotoxicant chemical species and mechanism of nephrotoxicity are unknown. The purpose of this study was to evaluate the in vivo and in vitro nephrotoxic potential of 2-amino-5-chlorophenol and 4-amino-3-chlorophenol, metabolites of 4-chloroaniline and 2-chloroaniline. A comparison was also made between the nephrotoxic potential of the aminochlorophenols and the corresponding aminophenols to examine the effect of adding a chloride group on the nephrotoxic potential of the animophenols. Male Fischer 344 rats (4/group) were given an i.p. injection of a chloroaniline or aminochlorophenol hydrochloride (1.5 mmol/kg), and aminophenol (1.0 or 1.5 mmol/kg), or vehicle, and renal function monitored at 24 and 48 h. Both aminochlorophenols induced smaller and fewer renal effects that the parent chloroanilenes in vivo. Also, 4-aminophenol was markedly more potent as a nephrotoxicant that 4-amino-3-chlorophenol, while 2-aminophenol and 2-amino-5-chlorophenol induced only mild change in renal function. In vitro, the phenolic compounds reduce p-aminohippurate accumulation by renal cortical slices at bath concentrations of 0.01 mM, while a bath concentration of 0.50 mM or greater was required for the chloroanilines. However, all compounds reduced tetraethylammonium accumulation at bath concentrations of 0.1-0.5 mM or greater. These results indicate that extrarenally-produced aminochlorophenol metabolites do not contribute to the mechanism of chloroaniline nephrotoxicity. Also, the reduced nephrotoxic potential of 4-amino-3-chlorophenol compared to 4-aminophenol could result from an altered ability of the aminochlorophenol to redox cycle or form conjugates.

Aminophenols↗

PubMed1993

Renal and hepatic toxicity of monochloroacetanilides in the Fischer 344 rat.

Chlorinated anilines are widely used chemical intermediates which have been shown to be nephrotoxicants and hepatotoxicants. A major metabolic pathway for the chloroanilines is via acetylation of the amino group to form chlorocetanilides. The purpose of this study was to examine the hepato- and nephrotoxic potential of the three monochloroacetanilides to determine if N-acetylation is an important biotransformation step for activation or detoxification of the chloroanilines in organ-directed toxicity. In one set of experiments, male Fischer 344 rats (4 rats/group) were injected intraperitoneally (i.p.) with a chloroacetanilide (CAA) (0.5, 1.0 or 1.5 mmol/kg) or vehicle and renal function monitored for 24 or 48 h. Liver function and tissue morphology also were determined at 24 or 48 h. None of the CAA were marked nephrotoxicants at doses of 0.5 or 1.0 mmol/kg. However, 4-CAA (1.5 mmol/kg) induced an increase in blood urea nitrogen concentration and kidney weight at 24 h and 3-CAA (1.5 mmol/kg) was lethal within 24 h. The decreasing order of in vivo nephrotoxic potential was found to be 4-CAA > or = 3-CAA > 2-CAA. Based on the elevation of ALT/GPT activity at 48 h, the order of hepatotoxic potential was found to be 4-CAA > 3-CAA, 2-CAA. In a second set of experiments, the in vitro effect of the chloroacetanilides on organic ion transport by renal cortical slices was examined. Both 3- and 4-CAA decreased organic ion accumulation at bath concentrations of 10(-5) M or greater, while 2-CAA had no effect at concentrations up to 10(-3) M. These results demonstrate that the order of nephrotoxic and hepatotoxic potential among the chloroacetanilide isomers is different than among the chloroanilines and that the chloroacetanilides were generally less potent as hepatotoxicants or nephrotoxicants than the corresponding chloroaniline. In addition, N-acetylation appears to be a detoxification rather than a bioactivation step in chloroaniline-induced liver or kidney injury.

Acetylation↗

PubMed1993

Successful re-treatment with taxol after major hypersensitivity reactions.

PURPOSE: To describe the successful re-treatment of eight patients who had major hypersensitivity reactions (HSRs) to taxol and to suggest a regimen for re-treating patients who develop major HSRs. PATIENTS AND METHODS: The treatment courses of eight patients who developed major HSRs and were rechallenged with taxol were reviewed. Patients in this report represent all patients who are known to have been rechallenged with taxol after major HSRs. RESULTS: The most common approach used to rechallenge patients consisted of premedication with multiple high doses of corticosteroids and H1- and H2-histamine antagonists followed by the initiation of the taxol infusion at a reduced rate. All patients who experienced major HSRs were rechallenged successfully. After the rechallenge, these patients received 32 additional courses of taxol without HSRs. CONCLUSION: Re-treatment with taxol after major HSRs is feasible using multiple high doses of corticosteroids and antihistamine premedications and a reduced taxol infusion rate under close supervision. This approach may represent a valid alternative to the termination of taxol; however, a prospective evaluation is required to determine the true efficacy of this approach.

Aged↗

PubMed1992

Acute renal and hepatic toxicity of 2-haloanilines in Fischer 344 rats.

Aniline and its halogenated derivatives are widely used as chemical intermediates. The purpose of this study was to determine the hepatotoxic and nephrotoxic potential of the 2-haloanilines. Male Fischer 344 rats (n > or = 4) were injected (i.p.) with 1.0 or 1.25 mmol/kg of: aniline (A), 2-fluoroaniline (2-FA), 2-chloroaniline (2-ClA), 2-bromoaniline (2-BrA), 2-iodoaniline (2-IA) or vehicle (0.9% saline, 2.5 ml/kg). All compounds were injected as hydrochloride salts. Renal and hepatic function was monitored 24 h after treatment. All of the 2-haloanilines induced oliguria, diminished kidney weight, tubular casts and decreased renal cortical slice accumulation of organic anions. Blood urea nitrogen (BUN) levels were increased (P < 0.05) by treatment with 1.0 or 1.25 mmol/kg of 2-FA, 2-ClA or 2-BrA. Hepatic alterations were also observed and characterized by elevated plasma ALT/GPT activity and altered morphology in the centrilobular region. The nephrotoxic and hepatotoxic potentials were similar among the 2-haloanilines but aniline was less toxic than its 2-halo derivatives. These results demonstrated that halogen substitution at the 2-position of aniline increased hepatic and renal toxicity. However, the severity of toxicity was not influenced by the nature of the halogen substituent.

Acute Disease↗

PubMed1992

Renal effects of N-(3,5-disubstitutedphenyl)-succinimides in the Fischer 344 rat.

Previous studies have demonstrated the importance of substitution at the 3- and 5-positions of the phenyl ring in N-phenylsuccinimides for the production of nephrotoxicants in this series of compounds. The purpose of this study was to determine if the electronic nature of the 3,5-substituents is an important determinant for nephrotoxic potential. Male Fischer 344 rats (four rats per group) were administered a single intraperitoneal injection of a succinimide (0.4 or 1.0 mmol kg-1) or vehicle, and the renal function was monitored for 48 h. Only N-(3,5-dichlorophenyl)succinimide (0.4 or 1.0 mmol kg-1) induced marked changes in renal function. Urine volume, BUN concentration and proteinuria were increased following N-(3,5-dinitrophenyl)succinimide (1.0 mmol kg-1) treatment but other renal parameters and renal morphology were unchanged in this treatment group. These results indicate that the presence of halogen atoms at the 3- and 5-positions of the phenyl ring in N-phenylsuccinimides is more important for nephrotoxic potential than the presence of non-halogen substituents. The reason why halogen substitution is an important determinant for N-phenylsuccinimide nephrotoxicity is unknown.

Animals↗

PubMed1992

Role of para-hydroxylation in phensuximide-induced urotoxicity in the Fischer 344 rat.

Phensuximide (PSX) is an antiepileptic agent which has been shown to induce hemorrhagic cystitis and mild nephrotoxicity following repeated administration in man or rats or when acutely administered to phenobarbital-pretreated rats. The purpose of this study was to explore the role of para-hydroxylation of the phenyl group of PSX in PSX-induced urotoxicity. Two PSX derivatives, 2-(4-fluorophenyl)-N-methylsuccinimide (FMPS) and N-methyl-2-(4-methylphenyl)succinimide (MMPS), were synthesized and evaluated for urotoxic potential. Male Fischer 344 rats (four rats/group) were administered intraperitoneally (i.p.) a succinimide (0.4 or 1.0 mmol/kg) or vehicle and renal function monitored for 48 h. In a separate experiment, rats were pretreated with phenobarbital (75 mg/kg/day; 3 days, i.p.) prior to succinimide or succinimide vehicle. In non-phenobarbital pretreated rats, acute FMPS or MMPS treatment had little effect on renal function or morphology at the doses tested. Hematuria (+) was noted in the FMPS (1.0 mmol/kg) group on post-treatment day 2. However, in the phenobarbital-pretreated rats, FMPS (0.4 or 1.0 mmol/kg) induced marked hematuria (++) and increased proteinuria while having little or no effect on other renal functional parameters or renal morphology. At killing, bladders of treated rats were distended with bloody urine and exhibited hemorrhagic areas within the bladder wall. In phenobarbital-pretreated rats, MMPS administration had little effect on any renal functional parameter measured or urological morphology. These results suggest that para-hydroxylation does not contribute to the hemorrhagic cystitis induced by PSX.

Animals↗

PubMed1992

Chemotherapy of cervix cancer with mitolactol (dibromodulcitol, NSC 104800) and cisplatin. A phase I study of the Gynecologic Oncology Group.

In this Phase I study, thirteen women with advanced cervix cancer were treated with mitolactol (dibromodulcitol) plus cisplatin to determine a maximum tolerable dose schedule. Response was not an objective of this study, but four partial responses were seen in nine patients with measurable lesions. In general, the therapy was well tolerated, but of the ten patients treated at the first dose level (cisplatin 50 mg/m2 intravenously on day 1 plus mitolactol 180 mg/m2 orally on days 2-6 every 3-4 weeks), 5 required de-escalations and 8 required delays because of toxicity. All three patients treated with cisplatin plus a higher dose of mitolactol (270 mg/m2 x 5) required dose reductions and delays for hematologic toxicity. The first dose level appears tolerable by patients with, and promising in treating, advanced cervix cancer.

Adult↗

PubMed1991

Enzyme immunoassay for detection of antibodies against eastern equine encephalomyelitis virus in sentinel chickens.

We developed an enzyme immunoassay (EIA) for the detection of immunoglobulin M (IgM) and IgG subclass antibodies directed against eastern equine encephalomyelitis (EEE) virus in chickens. The assays were compared with the serum plaque reduction neutralization test (PRNT) and the hemagglutination inhibition (HI) test for ability to detect antibodies against EEE virus in laboratory-infected birds. No cross-reactivity was detected in serum from chickens inoculated with St. Louis encephalitis or Highlands J virus. The interval after infection when EEE virus-specific antibodies were first detected by IgM and IgG EIAs was found to be similar to that determined by the PRNT and HI tests: 2 to 4 days. The IgG EIA, PRNT, and HI test detected antibodies to EEE virus for at least 27 to 30 days after inoculation. In contrast, serum from five of seven chickens did not contain detectable IgM 30 days after infection. Similarly, in all three naturally infected sentinel chickens from Maryland, IgM class antibody was undetectable 1 to 5 weeks after IgM was initially detected. EIAs provide simple and rapid alternatives to traditional tests for monitoring EEE virus infections in sentinel chicken flocks. Moreover, the IgM EIA provides a means to separate recently infected chickens from those infected greater than or equal to 1 month earlier.

Animals↗