Different protein sources in concentrate feed for dairy cows affect cheese-making properties and yield.

Soybean meal (SBM) is a commonly used protein source in feed. Yeast microbial protein could be used as a substitute for SBM, but its effect on cheese-making properties and yield is not known. Norwegian Red dairy cows (n = 48) in early or mid lactation were divided in 3 groups and fed a ration consisting of grass silage and concentrate, where the concentrates were barley based but with different additional protein sources. These were: completely barley based with no additional protein source (BAR), additional protein from SBM, or additional protein from yeast (Cyberlindnera jadinii; YEA). The SBM and YEA concentrates had a higher protein content than the barley concentrate. Four batches of cheese were made from pooled milk from each of the 3 groups of dairy cows. Milk samples were collected 5 times during the experiment. Milk from cows fed BAR concentrate showed inferior cheese-making properties (lower casein content, longer renneting time, lower content of phosphorus, and lower cheese yield) compared with SBM and YEA concentrates. Overall, SBM or YEA bulk milk had similar cheese-making properties, but when investigating individual milk samples, YEA milk showed better coagulation properties.

Risk factors for hospital-acquired infection during the SARS-CoV-2 pandemic.

OBJECTIVE: To evaluate risk factors for hospital-acquired infection (HAI) in patients during the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic, including historical and concurrent cohorts. DESIGN: Retrospective cohort. SETTING: Three Missouri hospitals, data from 1st January 2017 to 30th September 2020. PARTICIPANTS: Patients aged ≥18 years and admitted for ≥48 h. METHODS: Univariate and multi-variate Cox proportional hazards models incorporating the competing risk of death were used to determine risk factors for HAI. A-priori sensitivity analyses were performed to assess the robustness of the urine-, blood- and respiratory-culture-based HAI definition. RESULTS: The cohort included 254,792 admissions, with 7147 (2.8%) HAIs (1661 blood, 3407 urine, 2626 respiratory). Patients with SARS-CoV-2 had increased risk of HAI (adjusted hazards ratio 1.65, 95% confidence interval 1.38-1.96), and SARS-CoV-2 infection was one of the strongest risk factors for development of HAI. Other risk factors for HAI included certain admitting services, chronic comorbidities, intensive care unit stay during index admission, extremes of body mass index, hospital, and selected medications. Factors associated with lower risk of HAI included year of admission (declined over the course of the study), admitting service and medications. Risk factors for HAI were similar in sensitivity analyses restricted to patients with diagnostic codes for pneumonia/upper respiratory infection and urinary tract infection. CONCLUSIONS: SARS-CoV-2 was associated with significantly increased risk of HAI.

A simulational study of the indirect-geometry neutron spectrometer BIFROST at the European Spallation Source, from neutron source position to detector position.

The European Spallation Source (ESS) is intended to become the most powerful spallation neutron source in the world and the flagship of neutron science in upcoming decades. The exceptionally high neutron flux will provide unique opportunities for scientific experiments but also set high requirements for the detectors. One of the most challenging aspects is the rate capability and in particular the peak instantaneous rate capability, i.e. the number of neutrons hitting the detector per channel or cm2 at the peak of the neutron pulse. The primary purpose of this paper is to estimate the incident rates that are anticipated for the BIFROST instrument planned for ESS, and also to demonstrate the use of powerful simulation tools for the correct interpretation of neutron transport in crystalline materials. A full simulation model of the instrument from source to detector position, implemented with the use of multiple simulation software packages, is presented. For a single detector tube, instantaneous incident rates with a maximum of 1.7 GHz for a Bragg peak from a single crystal and 0.3 MHz for a vanadium sample are found. This paper also includes the first application of a new pyrolytic graphite model and a comparison of different simulation tools to highlight their strengths and weaknesses.

Feeding concentrates with different protein sources to high-yielding, mid-lactation Norwegian Red cows: Effect on cheese ripening.

Soybean meal is one of the most important protein sources in concentrate feeds for dairy cows. The objective of the present study was to provide knowledge on the effects of using a novel yeast microbial protein source (Candida utilis) in concentrate feed for dairy cows on the production and quality of a Gouda-type cheese. Forty-eight Norwegian Red dairy cows in early to mid lactation were fed a basal diet of grass silage, which was supplemented with 3 different concentrate feeds. The protein source of the concentrates was based on conventional soybean meal (SBM), novel yeast (C. utilis; YEA), or barley (BAR; used as negative control because barley has a lower protein content). The experiment was carried out for a period of 10 wk, with the first 2 wk as an adaptation period where all dairy cows were fed grass silage and the SBM concentrate. The cows were then randomly allocated to 1 of the 3 different compound feeds: SBM, yeast, or barley. Cheeses were made during wk 8 and 9 of the experiment, with 4 batches of cheese made from milk from each of the 3 groups. The cheeses made from milk from cows fed SBM concentrate (SBM cheese) had a higher content of dl-pyroglutamic acid and free amino acids than the other cheeses, indicating a faster ripening in the SBM cheeses. Despite these differences, the sensory properties, the microbiota, and the Lactococcus population at 15 wk of ripening were not significantly different between the cheeses. This experiment showed that although the raw materials used in the concentrate feed clearly influenced the ripening of the cheeses, this did not affect cheese quality. Yeast (C. utilis) as a protein source in concentrate feed for dairy cows can be used as a replacement for soybean meal without compromising the quality of Norwegian Gouda-type cheeses.

Risk factors for Clostridioides difficile infection in hospitalized patients and associated mortality in Japan: a multi-centre prospective cohort study.

BACKGROUND: Although population characteristics and antimicrobial prescribing practices suggest that the hospitalized population in Japan is at high risk of Clostridioides difficile infection (CDI), the epidemiology of CDI in Japan is poorly understood. AIM: This prospective cohort study aimed to investigate the epidemiology of CDI at 12 hospitals in Japan. METHODS: Patients with clinically significant diarrhoea (CSD) were enrolled. Stool specimens were tested for C. difficile by toxin A and/or B enzyme immunoassay (EIA) in the hospital laboratories, and a toxigenic culture and nucleic acid amplification tests were performed at a central laboratory. The risk factors of CDI and the impact of CDI on mortality were investigated. FINDINGS: In total, 566 patients with CSD were included in the analyses. A total of 152 patients received the diagnosis of CDI by Toxin A/B EIA, toxigenic culture, or nucleic acid amplification test. Factors associated with CDI included low albumin (adjusted odds ratio (aOR): 1.56; 95% confidence interval (CI): 1.03-2.34) and length of hospital stay before stool collection >18 days (aOR: 1.73; 95% CI: 1.09-2.75). CDI was associated with an increased mortality on univariate analysis (OR: 1.6, 95% CI: 1.0-2.6) but was not associated with an increased risk of mortality on multivariable analysis. CONCLUSION: Risk factors for CDI in Japan were similar to those identified in the USA and Europe. However, CDI was not associated with an increased risk of mortality in this population of patients with CSD.

Epidemiology and outcomes of Clostridium difficile infection in allogeneic hematopoietic cell and lung transplant recipients.

BACKGROUND: Clostridium difficile infection (CDI) is a common complication of lung and allogeneic hematopoietic cell (HCT) transplant, but the epidemiology and outcomes of CDI after transplant are poorly described. METHODS: We performed a prospective, multicenter study of CDI within 365 days post-allogeneic HCT or lung transplantation. Data were collected via patient interviews and medical chart review. Participants were followed weekly in the 12 weeks post-transplant and while hospitalized and contacted monthly up to 18 months post-transplantation. RESULTS: Six sites participated in the study with 614 total participants; 4 enrolled allogeneic HCT (385 participants) and 5 enrolled lung transplant recipients (229 participants). One hundred and fifty CDI cases occurred within 1 year of transplantation; the incidence among lung transplant recipients was 13.1% and among allogeneic HCTs was 31.2%. Median time to CDI was significantly shorter among allogeneic HCT than lung transplant recipients (27 days vs 90 days; P = .037). CDI was associated with significantly higher mortality from 31 to 180 days post-index date among the allogeneic HCT recipients (Hazard ratio [HR] = 1.80; P = .007). There was a trend towards increased mortality among lung transplant recipients from 120 to 180 days post-index date (HR = 4.7, P = .09). CONCLUSIONS: The epidemiology and outcomes of CDI vary by transplant population; surveillance for CDI should continue beyond the immediate post-transplant period.

Accuracy of Inpatient International Classification of Diseases, Ninth Revision, Clinical Modification Coding for Cytomegalovirus After Kidney Transplantation.

BACKGROUND: International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) coding for cytomegalovirus (CMV) has been used as a proxy for active CMV infection or disease occurring in the inpatient setting in retrospective studies of kidney transplant recipients using large amounts of administrative data. However, the accuracy of inpatient CMV coding has not been determined. METHODS: We identified 393 kidney transplant recipients who were readmitted to Barnes-Jewish Hospital in St. Louis, Missouri from January 1, 2007 to December 31, 2011 to determine the accuracy of the ICD-9-CM diagnosis code for CMV (078.5) in identifying active CMV infection or disease (asymptomatic viremia, CMV syndrome, or tissue-invasive CMV disease) in the inpatient setting, using microbiological, histopathologic, or ophthalmologic evidence for CMV as the gold standard. RESULTS: The sensitivity and positive predictive value of CMV coding in identifying active CMV infection or disease were 0.77 and 0.71, respectively. The specificity and negative predictive value were both 0.98. The sensitivity of CMV coding in identifying CMV syndrome or tissue-invasive CMV disease was 0.93. CONCLUSIONS: CMV coding had good accuracy in identifying active CMV infection or disease among readmitted kidney transplant recipients in our hospital. Further validation studies of CMV coding in other hospitals are needed to obtain more generalizable estimates of the accuracy of CMV coding.

Recurrent Clostridium difficile infection is associated with increased mortality.

Clostridium difficile infections (CDI) are associated with decreased survival, and up to 30% of CDI patients may experience a recurrence. Data on the impact of recurrent CDI on mortality are scarce. The purpose of this study was to determine whether recurrent CDI was independently associated with decreased 6-month survival compared with patients with CDI who did not develop a recurrence. We performed a retrospective cohort study at an academic, urban, tertiary care hospital. Data were collected from the electronic medical record and chart review. CDI patients were followed for 180 days from the end of their index hospital discharge or end of index CDI antibiotic treatment, whichever was later, to determine mortality. Kaplan-Meier analysis was used to compare patient mortality by recurrent CDI status. Cox proportional hazards models were used to determine independent risk factors for death within 180 days. In all, 3958 patients aged ≥ 18 years who developed an initial CDI episode from 2003 to 2009, including 421 patients with recurrent CDI, were included in the study. Thirty-six per cent of persons with recurrent CDI died within 180 days, compared with 26% of persons without CDI recurrence (log-rank p <0.001). Recurrent CDI was associated with significantly higher hazards of death within 180 days, adjusting for demographics, comorbidities and medications received during the index CDI hospitalization (hazard ratio 1.33; 95% CI 1.12-1.58). Recurrent CDI is associated with significantly increased risk of death within 6 months after completion of their initial CDI treatment compared with CDI patients who do not develop a recurrence.

Incidence, risk factors, and outcomes of delayed-onset cytomegalovirus disease in a large, retrospective cohort of heart transplant recipients.

BACKGROUND: Delayed-onset cytomegalovirus (CMV) disease can occur among heart transplant recipients after stopping anti-CMV prophylaxis. We evaluated a large, retrospective cohort of heart transplant recipients in the United States through the use of billing data from 3 Healthcare Cost and Utilization Project (HCUP) State Inpatient Databases (SID) to determine the epidemiology of delayed-onset CMV disease coded during hospital readmission. METHODS: We identified 2280 adult heart transplant recipients from 2004 to 2010 through the use of the California, Florida, and New York SID. Demographics, comorbidities, heart failure etiology, CMV disease, and inpatient death were identified. CMV disease was classified as early-onset (≤100 days) or delayed-onset (>100 days after transplant). Possible tissue invasion by CMV was determined through the use of codes for CMV pneumonitis, hepatitis, and gastrointestinal endoscopy. Multivariate analysis was performed with the use of Cox proportional hazards models. RESULTS: Delayed-onset CMV disease occurred in 7.5% (170/2280) and early-onset CMV disease occurred in 2.0% (45/2280) of heart transplant recipients. Risk factors for delayed-onset CMV disease included residence in a non-metropolitan locale (aHR. 1.8; 95% confidence interval [CI], 1.0-3.3) and ischemic cardiomyopathy as heart failure etiology (aHR, 1.8; 95% CI, 1.3-2.5). Inpatient death >100 days after transplant was associated with delayed-onset CMV disease with possible tissue invasion (aHR, 2.0; 95% CI, 1.1-3.8), transplant failure or rejection (aHR, 4.0; 95% CI, 2.7-5.8), and renal failure (aHR, 1.5; 95% CI, 1.1-2.0). CONCLUSIONS: Delayed-onset CMV disease is more common than early-onset CMV disease among heart transplant recipients. These results suggest that delayed-onset tissue-invasive CMV disease may be associated with an increased risk of death.

An investigation of imidazole and oxazole syntheses using aryl-substituted TosMIC reagents.

This article describes efficient and mild protocols for preparing polysubstituted imidazoles in a single pot from aryl-substituted tosylmethyl isocyanide (TosMIC) reagents and imines generated in situ. Traditional imine-forming reactions employing virtually any aldehyde and amine followed by addition of the TosMIC reagent delivers 1,4,5-trisubstituted imidazoles with predictable regiochemistry. Employing chiral amines and aldehydes, particularly those derived from alpha-amino acids, affords imidazoles with asymmetric centers appended to N-1 or C-5 with excellent retention of chiral purity. 1,4-Disubstituted imidazoles are also readily prepared by a simple variant of the above procedure. Selecting glyoxylic acid as the aldehyde component of this procedure leads to intermediates such as 48, which readily undergo decarboxylation and elimination of the tosyl moiety to deliver 1,4-disubstituted imidazoles in high yields. Alternatively, using NH(4)OH as the amine component in conjunction with a variety of aldehydes delivers 4, 5-disubstituted imidazoles in moderate to good yields in a single pot while avoiding the need for protecting groups. Finally, the facile preparation of mono- and disubstituted oxazoles from these TosMIC reagents and aldehydes is described.

Chitinolytic bacteria in the minke whale forestomach.

Minke whales consume large amounts of pelagic crustaceans. Digestion of the prey is initiated by indigenous bacteria in a rumen-like forestomach system. A major structural component of the crustacean exoskeleton is chitin, the beta-1,4-linked polymer of N-acetyl-D-glucosamine. The exoskeletons appear to dissolve completely in the non-glandular forestomach. Bacteria in the forestomach fluid of six krill-eating minke whales were enumerated and isolated using an anaerobic habitat-simulating culture medium. Median viable population densities ranged between 6.0 x 10(6) and 9.9 x 10(9) bacterial cells per mL forestomach fluid. Bacterial isolates (n = 44) cultured from the forestomach fluid of one minke whale mainly resembled strains of Eubacterium (25%), Streptococcus (18%), Clostridium (14%), and Bacteroides (11%). As much as 12% of the bacterial isolates were chitinolytic, while beta-N-acetylglucosaminidase activity was demonstrated in 54% of the isolates, and utilisation of N-acetyl-D-glucosamine was observed in 73%. The chitinolytic isolates resembled strains of Bacteroides, Bacteroidaceae, Clostridium, and Streptococcus. Scanning and transmission electron microscopy of partly digested krill from the minke whale forestomach revealed bacteria close to and inside the chitinous exoskeleton. The bacterial chitinase may act on the chitinous crustacean exoskeletons, thereby allowing other bacteria access to the nutritious soft inner tissues of the prey, and thus initiating its degradation and fermentation.

Cloning, mRNA localization and evolutionary conservation of a human 5-HT7 receptor pseudogene.

Initial experiments designed to clone novel serotonin receptor subtypes in the substantia nigra have led to the discovery of a transcribed human 5-HT7 receptor pseudogene that is expressed in a wide range of tissues. The original clone (S771) possessed greater than 90% homology to the 5-HT7 receptor sequence and was identified by a degenerate PCR approach. Expression of the pseudogene transcript was detected throughout the brain and peripheral tissues in general agreement with 5-HT7 mRNA localization. Interestingly, the transcript was detected in tissues not known to express the 5-HT7 receptor (i.e. liver and kidney). Analysis of genomic DNA explained the genesis of the human pseudogene via a processed parental transcript (retrotransposition) and led to the discovery of a species homologue in the rhesus monkey.

Identification of a human 5-HT6 receptor variant produced by alternative splicing.

The complexity of the 5-hydroxytryptamine (5-HT) (serotonin) receptor family has been increased by the findings that isoforms or splice variants exist for subtypes such as the 5-HT2B, 5-HT2C, 5-HT4 and 5-HT7 subtypes. Further molecular biological studies in our laboratory have demonstrated that a splice variant of the 5-HT6 receptor exists in the human brain. Experiments performed using a degenerate PCR approach from human caudate cDNA revealed a 5-HT6 receptor clone with a 289 bp deletion of the region coding for transmembrane IV through the third intracellular loop. This deletion produces a frameshift creating a downstream stop codon which results in a truncated protein containing 10 unique amino acids at its carboxyl end. The variant transcript occurs as a result of alternative splicing using an upstream donor site and the acceptor site from the first intron in the 5-HT6 receptor gene. The splicing pattern seen for this transcript was not detected in rat or mouse whole brain cDNA by PCR due to the lack of a consensus 5' donor site. Coexpression of the variant 5-HT6 transcript and the full length 5-HT6 transcript was observed in caudate and substantia nigra but not in hippocampus, cortex, cerebellum and thalamus. Transient transfection of a 5-HT6 variant construct into Cos-7 cells demonstrated that a truncated receptor was translocated to the membrane but appeared nonfunctional.

Production rates of volatile fatty acids in the minke whale (Balaenoptera acutorostrata) forestomach.

Minke whales (Balaenoptera acutorostrata) have developed a compartmentalized stomach system, which includes a non-glandular forestomach containing high concentrations of indigenous bacteria. The forestomach contents serve as microbial substrate, and samples were collected from five adult minke whales eating capelin (Mallotus villosus) and crustaceans (Thysanoessa sp.). Chemical analysis of the forestomach contents revealed that they consisted of crude protein (650 (SD 58) g/kg DM), lipid (330 (SD 77) g/kg DM) and water-soluble carbohydrates (53.3 (SD 7.3) g/kg DM). The contribution of energy from volatile fatty acids (VFA), produced by forestomach bacterial fermentation, to the total energy budget was estimated. The forestomach concentration of VFA ranged from 13.2 to 68.5 mmol/l, and the pH was 5.83 (SD 0.41). VFA pool size ranged from 72.8 to 638.1 mmol and represented from 0.169 to 2.107 kJ/kg live weight (W)0-75. Maximal recorded forestomach VFA production rate was 1694 mmol/h in one capelin-eating minke whale with 42.6 litres of forestomach fluid. Energy from VFA produced by forestomach fermentation represented 6-107 kJ/kg (W)0-75 per d, which accounts for only 0.9-16.9% of the average daily energy expenditure of minke whales. This study suggests that the bacterial fermentation in the minke whale forestomach varies, depending on the volume and the quality of substrate available, influencing fermentation rates and concentration of VFA. Due to the small relative size of the forestomach, the contribution of VFA to the daily energy requirement in minke whales would be of less importance than in ruminants even when assuming the same production rate of VFA as in a ruminant.

The 5-HT4 receptor: molecular cloning and pharmacological characterization of two splice variants.

Molecular cloning efforts have provided primary amino acid sequence and signal transduction data for a large collection of serotonin receptor subtypes. These include five 5-HT1-like receptors, three 5-HT2 receptors, one 5-HT3 receptor, two 5-HT5 receptors, one 5-HT6 receptor and one 5-HT7 receptor. Molecular biological information on the 5-HT4 receptor is notably absent from this list. We now report the cloning of the pharmacologically defined 5-HT4 receptor. Using degenerate oligonucleotide primers, we identified a rat brain PCR fragment which encoded a '5-HT receptor-like' amino acid sequence. The corresponding full length cDNA was isolated from a rat brain cDNA library. Transiently expressed in COS-7 cells, this receptor stimulates adenylyl cyclase activity and is sensitive to the benzamide derivative cisapride. The response is also blocked by ICS-205930. Interestingly, we isolated two splice variants of the receptor, 5-HT4L and 5-HT4S, differing in the length and sequence of their C-termini. In rat brain, the 5-HT4S transcripts are restricted to the striatum, but the 5-HT4L transcripts are expressed throughout the brain, except in the cerebellum where it was barely detectable. In peripheral tissues, differential expression was also observed in the atrium of the heart where only the 5-HT4S isoform was detectable.

Comparison of values of antibody to Bordetella pertussis antigens in young German and American men.

Pertussis is well controlled in the United States by routine childhood immunization. In contrast, this disease is endemic and epidemic in Germany because routine immunization has not been implemented. To gain information relating to the epidemiology of Bordetella pertussis infections, we examined the prevalence and magnitude of B. pertussis agglutinins and of IgG and IgA antibodies (detected by enzyme-linked immunosorbent assay) to four B. pertussis antigens--lymphocytosis-promoting factor, filamentous hemagglutinin, pertactin, and fimbriae-2--in the sera of 119 American university students and 119 German military recruits of similar age. Geometric mean titers of agglutinins and geometric mean values for IgG antibodies to the four antigens were two- to threefold higher in sera from the American students than in sera from German recruits. In contrast, the geometric mean IgA values and the percentage of subjects with detectable IgA antibodies to the four antigens were similar in the two populations. Since IgA antibody results mainly from infection and not from immunization, our data suggest that B. pertussis infections are common among both American and German young adults despite the marked difference in rates of clinical pertussis in the two countries.

Comparison of the Syva Microtrak enzyme immunoassay and Abbott Chlamydiazyme in the detection of chlamydial infections in women.

An enzyme immunoassay for detection of Chlamydia trachomatis antigen, Syva Microtrak, was compared with Abbott Chlamydiazyme to evaluate the performance of the Microtrak assay in the diagnosis of chlamydial genital tract infection in women. Duplicate endocervical swabs from 550 women were tested by both methods, and discrepancies were resolved by direct immunofluorescence on pelleted material from the collection tubes. Forty-six specimens were positive by the Syva Microtrak assay (resolved sensitivity, 95%), and 34 specimens were positive by the Chlamydiazyme assay (resolved sensitivity, 79%). The results from this small study suggest that the Syva Microtrak enzyme immunoassay is more sensitive than Chlamydiazyme for the detection of chlamydial antigen in endocervical specimens. This test should be useful for the diagnosis of chlamydial genital tract infection in females.

Digestion of herring by indigenous bacteria in the minke whale forestomach.

Northeastern Atlantic minke whales (Balaenoptera acutorostrata) have a multichambered stomach system which includes a nonglandular forestomach resembling that of ruminants. Bacteria from the forestomachs of herring-eating whales were enumerated and isolated in an anaerobic rumen-like culture medium (M8W medium). The total viable population of anaerobic bacteria ranged from 73 x 10 to 145 x 10/ml of forestomach fluid (n = 4). Lactobacillus spp. (19.7%), Streptococcus spp. (35.9%), and Ruminococcus spp. (12.8%) were the most common of the bacterial strains (n = 117) isolated by use of M8W medium from the forestomach fluid population of two minke whales. Most of the isolates stained gram positive (93.2%), 62.4% were cocci, and all strains were strictly anaerobic. The population of lipolytic bacteria in one animal, enumerated by use of a selective lipid medium, constituted 89.7% of the viable population. The total viable population of anaerobic bacteria in freshly caught and homogenized herring (Clupea harengus) ranged from 56.7 to 95.0 cells per gram of homogenized prey (n = 3) when M8W medium was used. Pediococcus spp. (30.6%) and Aerococcus spp. (25.0%) were most common of the bacterial strains (n = 72) isolated from the homogenized herring. Most of the bacterial strains were gram positive (80.6%), and 70.8% were cocci. Unlike the forestomach bacterial population, as many as 61.1% of the strains from the herring were facultatively anaerobic. All bacterial strains isolated from the prey had phenotypic patterns different from those of strains isolated from the dominant bacterial population in the forestomach, indicating that the forestomach microbiota is indigenous. Scanning electron microscopic examinations revealed large numbers of bacteria, surrounded by a glycocalyx, attached to partly digested food particles in the forestomach. These data support the hypothesis that symbiotic microbial digestion occurs in the forestomach and that the bacteria are indigenous to minke whales.

Comparison of four different immunoassays for detection of Toxoplasma-specific immunoglobulin G.

Serum specimens from 246 women of childbearing age were tested for immunoglobulin G (IgG) antibodies to Toxoplasma gondii by four different commercial assays: Abbott IMx microparticle enzyme immunoassay (EIA), Mercia Toxo-G EIA, Bartels Prima EIA, and bioMerieux Vitek (VIDAS) enzyme-linked fluorescent assay. A total of 27 specimens were initially positive with all four assays, 202 specimens were negative, and 17 specimens were discrepant (disagreement among the assays). After repeating tests for the 17 discrepant samples, five resolved (one was positive and four were negative). The 12 remaining discrepant samples were tested by an indirect fluorescent antibody (IFA) assay for Toxoplasma IgG antibodies; five specimens were positive for Toxoplasma IgG by IFA. The resolved sensitivities of the various kits ranged from 88% (bioMerieux VIDAS) to 94% (Abbott IMx), and the specificities were all 98%-99%. These results show that the four serologic tests used for detection of Toxoplasma IgG give very similar results and can all be readily used by clinical laboratories for screening purposes.