About one in seven cases of listeriosis occurs in pregnant women, and, although listeriosis is rare, it is the third leading cause of death from food-borne infections. Pregnancy-related listeriosis increases the risk for fetal and... more
About one in seven cases of listeriosis occurs in pregnant women, and, although listeriosis is rare, it is the third leading cause of death from food-borne infections. Pregnancy-related listeriosis increases the risk for fetal and neonatal mortality by approximately 21%. During pregnancy, infections are more likely to occur in the third trimester (66%) than the first trimester (3%). However, fetal and neonatal adverse effects are less common as gestational age increases or with older gestational age at birth. Pregnant women seem highly susceptible in some listeriosis outbreaks making up a large percentage of cases, whereas others contain very few. Whether this results from differences in strains of L. monocytogenes, exposures, or other factors remains to be determined. Food and Agriculture Organization of United Nations/World Health Organization (FAO/WHO) estimates the human lethal dose for 50% (LD50 ) for fetal/neonatal loss is 1.9 × 10(6) colony forming units (CFUs) L. monocytogen...
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Research Interests: Biology, Birth Weight, Biological Sciences, Inflammatory Immune Response, Infection and immunity, and 15 moreHumans, Liver, Diabetes mellitus, Female, Animals, Fetal Growth, Infection, Fetal Growth Restriction, Fetus, Gestational Age, Base Sequence, Epidemiologic Studies, immunoglobulin G, Interleukin, and Inflammatory response
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This paper describes the immunohistochemical localization of cAMP during limb chondrogenesis in talpid3 chick, brachypod mouse, and normal embryos. Comparisons were made between chick wing buds at Stages 22, 25, and 30, and mouse hind... more
This paper describes the immunohistochemical localization of cAMP during limb chondrogenesis in talpid3 chick, brachypod mouse, and normal embryos. Comparisons were made between chick wing buds at Stages 22, 25, and 30, and mouse hind limb buds at Days 11, 12.5, and 14. At Stage 22, the normal mesenchyme in the chick displayed areas of bright fluorescence compared to a lesser intense and more evenly distributed fluorescence in talpid3. Sections of the central region from normal Stage 25 limb buds exhibited an intense fluorescence that was uniformly distributed, whereas, in talpid3 staining was more, mosaic with some areas fluorescing brightly and others showing little fluorescence. At Stage 30 the staining pattern was similar between normal and talpid3, with the fluorescence being brighter in the cartilage tissue than in the surrounding soft tissue. Differences in the staining patterns of normal and brachypod limb tissue were not detectable. At Days 11 and 12.5, tissue from both gen...
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An estimated 2,500 cases of listeriosis occur annually in the United States. Listeriosis is particularly severe among pregnant women and immunocompromised individuals. Little is known regarding the effect of the food matrix on the ability... more
An estimated 2,500 cases of listeriosis occur annually in the United States. Listeriosis is particularly severe among pregnant women and immunocompromised individuals. Little is known regarding the effect of the food matrix on the ability of L. monocytogenes to survive in the gastrointestinal tract and cause systemic infection. Mice were inoculated with various doses of L. monocytogenes in skim milk, Half & Half, or whipping cream to determine whether differences in milk fat content influence the ability of L. monocytogenes to survive passage through the gut and infect the liver or spleen. The number of fecal samples positive for L. monocytogenes increased with increasing doses of L. monocytogenes for all three vehicles. The number of L. monocytogenes cells isolated from liver or spleen of mice dosed with L. monocytogenes was not significantly different among treatment vehicles. Dose-response models revealed that as the dosage of L. monocytogenes was increased in different milk vehi...
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Listeriosis results from exposure to the foodborne pathogen Listeria monocytogenes. Although many different strains of L. monocytogenes are isolated from food, no definitive tests currently predict which isolates are most virulent. The... more
Listeriosis results from exposure to the foodborne pathogen Listeria monocytogenes. Although many different strains of L. monocytogenes are isolated from food, no definitive tests currently predict which isolates are most virulent. The objectives of this study were to address two major data gaps for risk assessors, variability among L. monocytogenes strains in pathogenicity and virulence. Strains used in our monkey clinical trial or additional food isolates were evaluated for their virulence and infectivity in mice. All strains were equally pathogenic to immunocompromised mice, causing deaths to 50% of the population 3 days after exposure to doses ranging from 2 to 3 log CFU. Doses resulting in 50% deaths on the fifth day after administration were 1 to 2 log lower than those on the third day, indicating that the full course of pathogenicity exceeds the 3-day endpoint in immunocompromised mice. Three strains were chosen for further testing for their virulence and infectivity in liver...
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Neonatal, premature, or very low birth weight infants fed reconstituted powdered infant formula contaminated with Cronobacter (Enterobacter sakazakii) may develop infections resulting in severe outcomes such as septicemia, necrotizing... more
Neonatal, premature, or very low birth weight infants fed reconstituted powdered infant formula contaminated with Cronobacter (Enterobacter sakazakii) may develop infections resulting in severe outcomes such as septicemia, necrotizing enterocolitis, meningitis, or death. Infants who recover from infection may have morbidities such as hydrocephalus, mental retardation, or developmental delays. Although increasing age appears to reduce susceptibility to Cronobacter infection, it is not known at what age or why these infants become less susceptible. Our study objectives were to compare the susceptibilities of neonatal mice of different ages to Cronobacter sakazakii infection. Timed-pregnant CD-1 mice were allowed to give birth naturally. Neonatal mice were orally gavaged at postnatal days (PNDs) 1.5, 5.5, and 9.5 with a single dose of vehicle or 103, 107, or 1010 CFU/ml C. sakazakii strain MNW2 in reconstituted powdered infant formula. Pups were euthanized 7 days after challenge. Brain...
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Listeriosis, a severe disease that results from exposure to the foodborne pathogen Listeria monocytogenes, is responsible for ∼2,500 illnesses and 500 deaths in the United States each year. Pregnant women are 20 times more likely to... more
Listeriosis, a severe disease that results from exposure to the foodborne pathogen Listeria monocytogenes, is responsible for ∼2,500 illnesses and 500 deaths in the United States each year. Pregnant women are 20 times more likely to develop listeriosis than the general population, with adverse pregnancy outcomes that include spontaneous abortions, stillbirths, and neonatal meningitis. The objective of this study was to determine an infective dose that resulted in stillbirths and infectivity of selected tissues in pregnant guinea pigs. Pregnant guinea pigs were exposed orally on gestation day 35 to 104 to 108 L. monocytogenes CFU in sterile whipping cream. L. monocytogenes was recovered at 64, 73, 90, and 100% from the livers of animals infected with 105, 106, 107, and 108 CFU, respectively. In dams exposed to ≥106 CFU, L. monocytogenes was cultured from 50% of the spleen samples and 33% of the gallbladder samples. Eleven of 34 dams infected with ≥106 CFU delivered stillborn pups. L....
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Pregnant women are 20 times more likely to develop listeriosis than are members of the general population, and infection can result in abortion, stillbirth, or neonatal illness. The objective of this study was to orally challenge pregnant... more
Pregnant women are 20 times more likely to develop listeriosis than are members of the general population, and infection can result in abortion, stillbirth, or neonatal illness. The objective of this study was to orally challenge pregnant guinea pigs with Listeria monocytogenes to assess maternal and fetal tissue invasion at postinoculation days 2, 6, 9, and 21. The time course of invasion was followed by fluorescence microscopy and a traditional culture method. Guinea pigs were treated on gestation day 35 with L. monocytogenes doses ranging from 104 to 108 CFU. L. monocytogenes was isolated and viewed in maternal and fetal tissues as early as 2 days postinoculation. L. monocytogenes was isolated from placentas, fetal livers and brains, and maternal spleens at similar rates, suggesting that invasion of the spleen could be indicative of fetal invasion. When comparing fecal shedding, all animals treated with 104 CFU were shedding L. monocytogenes by postinoculation day 7, and all anim...
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The foodborne pathogen Listeria monocytogenes can cause infection in immunocompromised humans and in the fetuses of pregnant women. We have demonstrated that one group of genetically similar L. monocytogenes strains (random amplified... more
The foodborne pathogen Listeria monocytogenes can cause infection in immunocompromised humans and in the fetuses of pregnant women. We have demonstrated that one group of genetically similar L. monocytogenes strains (random amplified polymorphic DNA [RAPD] type 9) dominate and persist in several independent fish processing plants. The purpose of the present study was to determine the virulence potential of one RAPD type 9 strain (La111), one human clinical strain (Scott A), and one monkey clinical strain (12443) in a pregnant guinea pig model. Animals were orally exposed to 108 CFU of L. monocytogenes in whipping cream on gestation day (GD) 36 and euthanized on GD 42, 45, or 56. Strains 12443 and Scott A were shed from treated animals for 20 days, whereas La111 was shed only in the first 10 days. Strains 12443 and Scott A were recovered from maternal liver, spleen, and gallbladder on all 3 days of euthanization, whereas La111 was recovered only at GD 45 and 56. Scott A was not isola...
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Listeria monocytogenes is a food-borne pathogen that can result in adverse pregnancy outcomes, such as stillbirth or premature delivery. The Mongolian gerbil was recently proposed as the most appropriate small-animal model of listeriosis... more
Listeria monocytogenes is a food-borne pathogen that can result in adverse pregnancy outcomes, such as stillbirth or premature delivery. The Mongolian gerbil was recently proposed as the most appropriate small-animal model of listeriosis due to its susceptibility to the same invasion pathways as humans. The objectives of this study were to investigate invasion and adverse pregnancy outcomes in gerbils orally exposed to L. monocytogenes , to compare the dose-response data to those of other animal models, and to investigate differences in the responses of pregnant versus nonpregnant gerbils. Gerbils were orally exposed to 0 (control), 10 3 , 10 5 , 10 7 , or 10 9 CFU L. monocytogenes in whipping cream. L. monocytogenes was recovered in a dose-dependent manner from fecal samples, adult organs, and pregnancy-associated tissues. Dams exposed to 10 9 CFU had more invaded organs and higher concentrations of L. monocytogenes in almost all organs than nonpregnant animals, though no differenc...
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The objective of this study was to test for reduction in pediatric blood lead levels (BLLs) in Bombay, India, by comparing BLLs collected in 2002 (after use of leaded gasoline was phased out in Bombay) to those collected in a study... more
The objective of this study was to test for reduction in pediatric blood lead levels (BLLs) in Bombay, India, by comparing BLLs collected in 2002 (after use of leaded gasoline was phased out in Bombay) to those collected in a study conducted by the George Foundation in 1997 ...
Research Interests: Environmental Monitoring, Adolescent, Urban Health, Multidisciplinary, India, and 15 moreHerbal Medicine, Seasonality, Humans, Child, Vehicle Emissions, Lead, Lead Exposure, Lead Poisoning, Particulate Matter, Seasons, Public Health System, Gasoline, Environmental Exposure, Blood Lead, and Geometric mean
In 2013, an estimated 2.8 million newborns died and 2.7 million were stillborn. A much greater number suffer from long term impairment associated with preterm birth, intrauterine growth restriction, congenital anomalies, and perinatal or... more
In 2013, an estimated 2.8 million newborns died and 2.7 million were stillborn. A much greater number suffer from long term impairment associated with preterm birth, intrauterine growth restriction, congenital anomalies, and perinatal or infectious causes. With the approaching deadline for the achievement of the Millennium Development Goals (MDGs) in 2015, there was a need to set the new research priorities on newborns and stillbirth with a focus not only on survival but also on health, growth and development. We therefore carried out a systematic exercise to set newborn health research priorities for 2013-2025. We used adapted Child Health and Nutrition Research Initiative (CHNRI) methods for this prioritization exercise. We identified and approached the 200 most productive researchers and 400 program experts, and 132 of them submitted research questions online. These were collated into a set of 205 research questions, sent for scoring to the 600 identified experts, and were assess...
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During the past century, the microbiological safety of the U.S. food supply has improved; however, many foodborne illnesses and outbreaks occur annually. Hence, opportunities for the food industry to improve the safety of both domestic... more
During the past century, the microbiological safety of the U.S. food supply has improved; however, many foodborne illnesses and outbreaks occur annually. Hence, opportunities for the food industry to improve the safety of both domestic and imported food exist through the adoption of risk-based preventive measures. Challenging food safety issues that are on the horizon include demographic changes to a population whose immune system is more susceptible to foodborne and opportunistic pathogens, climate changes that will shift where food is produced, and consumers' preferences for raw and minimally processed foods. Increased environmental and product testing and anonymous data sharing by the food industry with the public health community would aid in identifying system weaknesses and enabling more targeted corrective and preventative actions. Clinicians will continue to play a major role in reducing foodborne illnesses by diagnosing and reporting cases and in helping to educate the ...
Research Interests: Food Safety, Public Health, Food Microbiology, Quality Control, Biological Sciences, and 10 moreDisease Outbreaks, Humans, United States, Food Industry, Public Health Surveillance, Food Contamination, Clinical Infectious Diseases, Foodborne diseases, Medical and Health Sciences, and Epidemiological monitoring
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Research Interests: Risk, Risk assessment, Multidisciplinary, Food Microbiology, Risk Analysis, and 12 moreHumans, Low Dose, Maximum Likelihood, United States, Comparative modeling, Risk Assessment, Statistical Model, Likelihood Functions, Campylobacter jejuni, Microbial Risk Assessment, maximum likelihood estimate, and Foodborne diseases
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To investigate the effects of bisphenol A (BPA) on embryo and uterine factors in embryo implantation, timed pregnant C57BL6 females were treated subcutaneously with 0, 0.025, 0.5, 10, 40, and 100mg/kg/day BPA from gestation days 0.5-3.5.... more
To investigate the effects of bisphenol A (BPA) on embryo and uterine factors in embryo implantation, timed pregnant C57BL6 females were treated subcutaneously with 0, 0.025, 0.5, 10, 40, and 100mg/kg/day BPA from gestation days 0.5-3.5. In 100mg/kg/day BPA-treated females, no implantation sites were detected on day 4.5 but retention of embryos in the oviduct and delayed embryo development were detected on day 3.5. When untreated healthy embryos were transferred to pseudopregnant females treated with 100mg/kg/day BPA, no implantation sites were detected on day 4.5. In 40 mg/kg/day BPA-treated females, delayed implantation and increased perinatal lethality of their offspring were observed. Implantation seemed normal in the rest BPA-treated groups or the female offspring from 40 mg/kg/day BPA-treated group. These data demonstrate the adverse effects of high doses of BPA on processes critical for embryo implantation: embryo transport, preimplantation embryo development, and establishment of uterine receptivity.
Research Interests: Pregnancy, Reproductive toxicology, bisphenol A, Mice, Female, and 13 moreAnimals, Blastocyst, Embryo Transfer, Phenols, Embryonic Development, Public health systems and services research, Uterus, Embryos, Embryo Development, Adverse effect, embryo implantation, Paediatrics and reproductive medicine, and Pharmacology and pharmaceutical sciences
Research Interests: Apoptosis, Pregnancy, Placenta, Reproductive toxicology, Female, and 15 moreAnimals, Listeria monocytogenes, Cell Death, Bacteria, Apoptose, Public health systems and services research, Guinea Pig, Listeriosis, Gestational Age, Gestation, Fetal death, Spontaneous Abortion, Guinea pigs, Paediatrics and reproductive medicine, and Pharmacology and pharmaceutical sciences
Diethylene glycol monomethyl ether (DEGME), ethylene glycol monomethyl ether (EGME) and their common metabolite, methoxyacetic acid (MAA) have been associated with adverse reproductive effects. The objective of this research is to... more
Diethylene glycol monomethyl ether (DEGME), ethylene glycol monomethyl ether (EGME) and their common metabolite, methoxyacetic acid (MAA) have been associated with adverse reproductive effects. The objective of this research is to investigate the effects of DEGME, EGME and MAA on in vitro chondrogenesis and the mechanisms by which these effects occur. Micromass cultures were exposed to DEGME, EGME or MAA for 5 days and proteoglycan abundance and cell proliferation determined. Longer-term 9- and 14-day cultures were exposed to MAA and apoptosis analyzed. All three chemicals decreased proteoglycan abundance and cell proliferation at the highest dose tested (100 microL/mL). However, only MAA showed a dose-dependent effect for both parameters at 0.01, 10, and 100 microL/mL. Furthermore, micromass cultures show an increase in apoptotic cells which when treated with MAA suggest that cell death could result from induced apoptosis. These results suggest that effects of DEGME and EGME are the result of generalized toxicity, but their metabolite MAA induces mitochondrial-mediated apoptosis during in vitro chondrogenesis.
Research Interests: Mitochondria, Apoptosis, In Vitro, Reproductive toxicology, Animals, and 15 moreCell Death, Polymerase Chain Reaction, Caspase, Apoptose, Proteoglycans, Public health systems and services research, Time Factors, Reproductive, Chondrogenesis, Cell Proliferation, Ethylene Glycol, DNA fragmentation, Chick embryo, Paediatrics and reproductive medicine, and Pharmacology and pharmaceutical sciences
Dexamethasone (DEX), a synthetic glucocorticoid, has been suggested to accelerate fetal lung maturation and is sometimes used clinically during premature labor for this purpose. These experiments were initiated to measure the rate of... more
Dexamethasone (DEX), a synthetic glucocorticoid, has been suggested to accelerate fetal lung maturation and is sometimes used clinically during premature labor for this purpose. These experiments were initiated to measure the rate of transfer and metabolism of DEX by the human placenta. Lobules from full term (38-41 weeks) human placentas, obtained immediately after delivery, were perfused on both maternal and fetal sides. Radiolabeled (14C) DEX and tritiated water were infused into the maternal artery. Samples were taken at timed intervals throughout the perfusion period from the maternal artery (MA), maternal vein (MV), fetal artery (FA) and fetal vein (FV). Transport was determined by liquid scintillation spectroscopy and metabolism of DEX was determined by reversed phase HPLC. Tritiated water reached equilibrium between the maternal and fetal circulations within 75 min of perfusion, while total 14C-labeled radioactivity attained equilibrium after 180 min. HPLC revealed one metabolite of DEX which co-migrated with an 11-ketobetamethasone standard. The concentration of metabolite at 10, 30, 120, and 240 min in the FV were 9, 22, 40, and 41 ng/ml, respectively, and in the MV were 15, 28, 46, and 48 ng/ml, respectively. However, the ratio of metabolite/DEX was greater at 10 min in the FV (0.39) than in the MV (0.08). These data suggest that DEX crosses the human term placenta, that an enzyme in the placenta metabolizes DEX into an 11-keto-metabolite, and that a greater metabolite:DEX ratio is found at earlier times in the fetal circulation than in the maternal circulation.
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Recent studies have suggested that subclinical infection may be an important cause of low birth weight. Campylobacters are important human pathogens, causing septicemia and occasionally abortion, premature labor, or severe perinatal... more
Recent studies have suggested that subclinical infection may be an important cause of low birth weight. Campylobacters are important human pathogens, causing septicemia and occasionally abortion, premature labor, or severe perinatal infection. The potential role of oral species of Campylobacter in mediating adverse pregnancy outcomes in animal models has not yet been determined. Our objective was to determine the effects of Campylobacter rectus (C. rectus) infection on pregnancy outcomes in a mouse model. On embryonic day (E) 7.5, pregnant mice received a subcutaneous, intra-chamber challenge with live C. rectus at concentrations of 0, 10(7) or 10(9) colony forming units (CFU)/ml. They were sacrificed on E 16.5 and fetuses were evaluated for stage of development, weight, and crown-rump length. Dams receiving C. rectus had more fetal resorptions after challenge with 10(7) or 10(9) CFU/ml (24.1% and 30.1%, respectively) than controls (9%). Higher numbers of growth-restricted fetuses were also observed in the C. rectus challenged groups (21%) as compared to controls (2.3%). Fetuses from dams challenged with 10(9) CFU/ml weighed less (0.49 +/- 0.05 g) and had shorter crown-rump lengths (14.69 +/- 0.56 mm) than controls (0.53 +/- 0.04 g; 15.54 +/- 0.63 mm). C. rectus was detected by polymerase chain reaction (PCR) in the placentas from both treated groups and in maternal liver tissues from the 10(9) CFU/ml challenged group. Remote subcutaneous maternal C. rectus infection increases fetal resorptions and fetal growth restriction in a mouse model. The effects of an oral C. rectus infection on pregnancy remain to be determined.
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Perfluorocarboxylic acids (PFCAs), namely perfluorooctanoic acid (PFOA) and perfluorononanoic acid (PFNA), have been identified as persistent, bioaccumulative and potentially toxic compounds. The structural analog, 8-2 fluorotelomer... more
Perfluorocarboxylic acids (PFCAs), namely perfluorooctanoic acid (PFOA) and perfluorononanoic acid (PFNA), have been identified as persistent, bioaccumulative and potentially toxic compounds. The structural analog, 8-2 fluorotelomer alcohol (8-2 fTOH) is considered the probable precursor of these stable metabolites. Because simultaneous quantification is needed for volatile and non-volatile perfluorinated chemicals (PFCs) in complex matrices, a GC/MS method was developed and tested based on selected ion monitoring of perfluorinated alkyl parent chain fragment ions. Although the method requires a derivatization step, combined GC/MS analysis of PFCA-me's and FTOHs increases analytical efficiency and decreases sample analysis time. The method instrument detection limits are between 7.1 and 24.5 ng/mL extract (MTBE), and the method quantification limits are below 50 ng/mL serum or ng/g liver for all PFCs investigated. Recoveries from mouse serum and liver homogenates, which were spiked with FTOHs and PFCAs at levels of 25 and 200 ng/mL or ng/g, ranged from 81 to 101%. Finally, the utility of the method was demonstrated by dosing male CD-1 mice with 30 mg/kg-BW of 8-2 fTOH and quantifying PFCs 6h post-treatment. The advantages of this method are (1) the simultaneous detection of both volatile and non-volatile fluorotelomer-based chemicals in complex matrices, such as mammalian tissues, (2) as a confirmatory method to LC-MS/MS, and (3) as an alternative method of analysis for laboratories without access to LC-MS/MS.
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The fungus Fusarium verticillioides infects maize and produces fumonisins. The purpose of this study was to determine the ability of F. verticillioides to produce fumonisins in synthetic and natural soils and their biological availability... more
The fungus Fusarium verticillioides infects maize and produces fumonisins. The purpose of this study was to determine the ability of F. verticillioides to produce fumonisins in synthetic and natural soils and their biological availability to maize roots. Maize seeds were inoculated with a pathogenic strain of F. verticillioides (MRC826) and planted in synthetic and three different natural soils. There were statistically significant reductions in stalk weight and root mass and increased leaf lesions in the MRC826-treated seedlings in all soil types. Fumonisins were detected in all of the soils of seedlings grown from MRC826-inoculated seeds. The fumonisin produced in the soils was biologically available to seedlings as demonstrated by the statistically significant elevation of free sphingoid bases and sphingoid base 1-phosphates in their roots. These results indicate that F. verticillioides produced fumonisins in the autoclaved synthetic and natural soils and that the fumonisin produced is biologically available on the basis of evidence of inhibition of ceramide synthase.
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The fungus Fusarium verticillioides infects maize and produces fumonisins, inhibitors of ceramide synthase. Seeds of the cultivar Silver Queen were inoculated with fumonisin-producing or non-fumonisin-producing strains of F.... more
The fungus Fusarium verticillioides infects maize and produces fumonisins, inhibitors of ceramide synthase. Seeds of the cultivar Silver Queen were inoculated with fumonisin-producing or non-fumonisin-producing strains of F. verticillioides. Leaf lesion incidence and severity of effects on root and stalk growth were significantly correlated with fumonisin in roots and disruption of sphingolipid metabolism in roots. Uninoculated seeds grown in soil watered with solutions of fumonisin B1 exhibited above-ground symptoms indicative of F. verticillioides-induced seedling disease and dose-dependent reduction in root mass that was inversely correlated with fumonisin B1, sphingoid bases, and sphingoid base 1-phosphates in roots. There was also evidence of an adaptive response to disrupted sphingolipid metabolism in both the virulence and watering assays, suggesting induction of pathways responsible for metabolism of sphingoid base 1-phosphates after prolonged exposure. The results suggest that fumonisin, and its effects on sphingolipids, could contribute to all aspects of F. verticillioides maize seedling disease.
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Listeria monocytogenes, isolated from outbreaks in either human or nonhuman primate populations, was administered orally at doses ranging from 106 to 1010 CFU. Four of 10 treated animals delivered stillborn infants. L. monocytogenes was... more
Listeria monocytogenes, isolated from outbreaks in either human or nonhuman primate populations, was administered orally at doses ranging from 106 to 1010 CFU. Four of 10 treated animals delivered stillborn infants. L. monocytogenes was isolated from fetal tissue, and the pathology was consistent with L. monocytogenes infection as the cause of pregnancy loss. For all pregnancies resulting in stillbirths, L. monocytogenes was isolated from maternal feces, indicating that L. monocytogenes had survived and had probably colonized the gastrointestinal tract. Antibodies and antigen-specific lymphocyte proliferation against Listeria increased in animals that had stillbirths.
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Research Interests: Food Safety, Biological Sciences, Pregnancy, Models, Placenta, and 15 moreFemale, Animals, Listeria monocytogenes, Infection, Bacteria, Immune system, Feces, Pregnant Women, Listeriosis, Macaca Mulatta, Fetus, Lethal Dose, Logistic Model, Food and Drug Administration, and Medical and Health Sciences
Our previous animal studies showed that maternal Porphyromonas gingivalis infection in a subcutaneous chamber is associated with hepatic and uterine translocation, as well as systemic induction of maternal inflammatory responses, both of... more
Our previous animal studies showed that maternal Porphyromonas gingivalis infection in a subcutaneous chamber is associated with hepatic and uterine translocation, as well as systemic induction of maternal inflammatory responses, both of which were associated with fetal growth restriction (FGR). However, P. gingivalis-challenged dams had fetuses with either FGR (2 standard deviations below mean weight of nonchallenged dams) or normal weight. Therefore, the objective of this study was to determine whether maternal infection with P. gingivalis compromises normal fetal development via direct placental invasion and induction of fetus-specific placental immune responses characterized by a proinflammatory Th1-type cytokine profile. P. gingivalis-specific DNA was detected in placentas and fetuses of FGR and normal littermates from P. gingivalis-infected dams. Th1- and Th2-type cytokine mRNA as well as tumor necrosis factor alpha and transforming growth factor β2 mRNA were examined in place...