Enterotoxigenic Escherichia coli (ETEC) causes neonatal and post-weaning diarrhea in pigs. In order to determine the risk factors, rectal/fecal swabs and visceral organs obtained from pig farms in two regions of South Africa were analyzed microbiologically against risk variables. Seventy-two percent of young pigs were found to be positive for ETEC toxin genes; estB (38.9%), estB/STAP (25%), and estB/LT (13.9%) were dominant. Risk factors for ETEC-diarrhea in pigs include: leaving sick piglets in a pen with healthy piglets [odds ratio (OR) = 33.52; P < 0.0001]; water spillage in pen (OR = 42.87; P < 0.0001); hypothermic piglets (OR = 7.29; P < 0.0001); runt piglets in pen with healthy littermates (OR = 3.65; P < 0.0001); and prolonged use of antibiotics (OR = 3.05; P = 0.05).
Animals ; Animals, Newborn ; Diarrhea ; epidemiology ; microbiology ; Escherichia coli ; genetics ; isolation & purification ; Escherichia coli Infections ; epidemiology ; microbiology ; veterinary ; Genes, Bacterial ; Prevalence ; Rectum ; microbiology ; Risk Factors ; South Africa ; Swine ; Swine Diseases ; epidemiology ; microbiology ; Weaning

Animals ; Animals, Newborn ; Bifidobacterium ; growth & development ; metabolism ; Gastrointestinal Tract ; microbiology ; Liver Function Tests ; Parenteral Nutrition ; methods ; Rabbits

Helicobacter pylori (H. pylori) infection is acquired mainly in early childhood but the precise transmission routes are unclear. This study examined the maternal H. pylori infection status in order to determine the potential of perinatal transmission. These issues were investigated using an experimental murine model, the Mongolian gerbil, which has been reported to be the most suitable laboratory animal model for studying H. pylori. Pregnant Mongolian gerbils, infected experimentally with H. pylori, were divided into two groups. The stomachs of the mother and litters were isolated and assessed for the transmission of H. pylori at the prenatal period (2 weeks after pregnancy) and at the parturition day. The bacterial culture, polymerase chain reaction (PCR) and rapid urease test were used to examine the presence of the transmitted H. pylori. There was no H. pylori observed in any of the fetuses during pregnancy and in the litters at parturition. This suggests that vertical infection during the prenatal period or delivery procedure is unlikely to be route of mother-tochild transmission of a H. pylori infection.
Animals ; Animals, Newborn ; Disease Models, Animal ; *Disease Transmission, Vertical ; Female ; Gerbillinae ; Helicobacter Infections/microbiology/*transmission ; Helicobacter pylori/*growth&development ; Male ; Polymerase Chain Reaction ; Pregnancy ; Pregnancy Complications, Infectious/*microbiology ; Specific Pathogen-Free Organisms ; Stomach Diseases/*microbiology

OBJECTIVETo identify epidemic status of murine typhus in Hongta areas of Yuxi city and to provide evidence for control and prevention of the disease.

METHODSSerologic survey was conducted among residents and rodents. Isolation of Rickettsia moseri was performed.

RESULTSThe overall infection rate among general population was 28.92% (96/332) with geometric meantiter (GMT) as 10.83 and there was no difference between males and females (26.71%, 43/161 vs. 30.99%, 53/171, P > 0.05). Significant differences were found between age groups (P < 0.05) with positive rates of 29.63% (8/27), 18.06% (13/72), 39.62% (42/106), 27.50% (22/80) and 23.40% (11/47) among age groups 0-6, 7-18, 19-39, 40-59 and over 60, respectively. The overall rate of infection in mouse was 44.95% (89/198) with GMT as 30.30. Five isolates of R. moseri from mouse specimen, three from fleas plus one case of murine typhus were diagnosed. Rattus norvegicus and Rattus flavipectus were the predominant species of rodent animals (99.49%, 197/198) and Xenopsylla cheopis was the major species of vector (74.26%, 303/408). Flea index and mouse density were 2.06 and 11.13% respectively.

CONCLUSIONHigh infection rates on R. moseri were demonstrated in rodents and residents as well as high risk of murine typhus outbreak might occur in these areas.

Adolescent ; Adult ; Animals ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Mice ; Middle Aged ; Rats ; Rodent Diseases ; epidemiology ; microbiology ; transmission ; Siphonaptera ; microbiology ; Typhus, Endemic Flea-Borne ; epidemiology ; microbiology ; transmission ; Young Adult

OBJECTIVETo investigate the inhibitory effect of Lactobacillus rhamnosus GG ( LGG) against Cronobacter-induced meningitis in neonatal rats.

METHODSThe cell adhesion and invasion capacities of Cronobacter were assayed in Caco-2 cells, and the optimal time length and concentration of the bacterium for infection were determined. The suppressive effects of LGG on the adhesion and invasion of Cronobacter in caco-2 cells were tested by competitive and exclusion experiments, and its inhibitory effect against Cronobacter-induced meningitis was evaluated in neonatal rats.

RESULTSCronobacter showed aggressive adhesion to caco-2 cells with an optimal infection time of 3 h. LGG produced a concentration-dependent inhibition of Cronobacter adhesion and invasion by competing with and excluding the latter for cell adhesion. In neonatal rats, LGG showed an obvious preventive effect and also a moderate therapeutic effect against Cronobacter-induced meningitis.

CONCLUSIONLGG can inhibit Cronobacter entry across the intestinal barrier to achieve preventive and therapeutic effects against Cronobacter-induced meningitis.

Animals ; Animals, Newborn ; Bacterial Adhesion ; Caco-2 Cells ; Cronobacter ; pathogenicity ; Enterobacteriaceae Infections ; therapy ; Humans ; Intestines ; microbiology ; Lactobacillus rhamnosus ; Meningitis, Bacterial ; therapy ; Probiotics ; Rats

OBJECTIVETo examine the expression of tumor necrosis factor in placenta of pregnant rats with chronic periodontitis.

METHODSTwenty Wistar female rats were randomly divided into two groups, control (n = 8) and experimental group (n = 12). The periodontitis model was established in the experimental group. The females and males in the two groups got together four weeks later. Nineteen days after pregnancy all rats were executed and placenta collected. The delivery time and neonatal birth weight were recorded and the pathological changes of periodontal tissue observed. Tumor necrosis factor (TNF) expression was examined in placenta by real-time quantitative polymerase chain reaction analysis.

RESULTSThe animal model of chronic periodontitis was successfully established. Experimental group delivered 30 offspring and the control group 56 offspring. The average number of pups born alive per litter in experimental group (4.1 ± 2.2) was significantly lower than that in control group (9.2 ± 2.2), P < 0.05. The birth weight of pups in experimental group [(5.01 ± 0.43) g] was significantly lower than that in the control group [(5.79 ± 0.53) g], P < 0.05. The relative quantitative expression of TNF was (1.807 ± 0.265) in experimental group the and (1.003 ± 0.021) in the control group (P = 0.001).

CONCLUSIONSChronic periodontitis may be related to preterm low birth weight.

Aggregatibacter actinomycetemcomitans ; Animals ; Animals, Newborn ; Birth Weight ; Chronic Periodontitis ; metabolism ; microbiology ; Disease Models, Animal ; Female ; Fusobacterium nucleatum ; Placenta ; metabolism ; Porphyromonas gingivalis ; Pregnancy ; Pregnancy Complications, Infectious ; metabolism ; microbiology ; Prevotella intermedia ; Random Allocation ; Rats ; Rats, Wistar ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVEScrub typhus is an infectious disease due to Orientia tsutsugamushi transmitted by infected chigger mites. Scrub typhus has long been recognized to occur in southern areas of China, but has recently been increasingly often reported from the north since the first case was reported in Mengyin County, Shandong Province in 1986. The key objectives of the present study were to investigate the clinical manifestations and epidemic factors of scrub typhus in children from the northern new natural foci.

METHODSThe case records of 56 children with scrub typhus who were admitted to the 5 hospitals of Fei County from September 1993 to January 2004 were reviewed. Orientia tsutsugamushi (Ot) was isolated from the cases. Based on ecological observations on the composition, seasonal fluctuation of animal hosts and chigger mites, Ot was isolated from rodents and chiggers. IgG antibodies to Ot was detected by IFA. Genotypes of the Ot isolates were also identified by nested PCR.

RESULTSAmong 56 children scrub typhus cases, 46 were male, 10 were female; 96% exhibited typical eschars or ulcers, 100% cases had high fever, skin rashes were observed in 55 cases (98%), and regional lymphadenopathy occurred in 48 cases (86%). All cases came from countryside, and all had histories of exposure to the crop field. fifty-one serum samples of suspected patients with scrub typhus were collected, 48 were positive for antibodies to Ot. The serotypes were Gilliam types. The cases only appeared in September to December with the peak at mid and late October. Leptotrombidium (L.) scutellare was the most important vector causing scrub typhus in the foci. Apodemus (A.) agrarius was the main host animals of Ot in the crop field. Totally 26 strains were isolated from patients, rodents, and chigger mites. The serotypes of 24 out of the 26 isolates were Gilliam types, while the genotypes of these isolates were Kawasaki types. The serotypes of the other 2 isolates were identical and both were Karp types.

CONCLUSIONChildren scrub typhus patients were frequently seen in the new natural foci of Shandong province. Exposure history, typical eschars or ulcers, and presence of IgG antibody were the important indexes to diagnose the disease.

Adolescent ; Animals ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Mice ; parasitology ; Orientia tsutsugamushi ; isolation & purification ; Scrub Typhus ; epidemiology ; Seasons ; Trombiculidae ; microbiology

Pneumocystis carinii is a pulmonary pathogen of immunocompromised humans or other mammals. Its infection results from activation of organisms involved in latent infection or from new infection through the air. Almost all children are known to be infected within 2 to 4 years of birth, though prenatal transplacental transmission has not yet been demonstrated. In this study we observed experimental P. carinii infection in neonatal rats, thus investigating the possibility of transplacental vertical transmission by Diff-Quik staining of the lung impression smears and in-situ hybridization for lung sections. The positive rate of P. carinii infection in immunosuppressed maternal rats was 100%, but that in normal maternal rats was 0%. Cystic forms of P. carinii were observed in three of six 1-week old neonatal rats born of heavily infected mothers, but none of them was positive by in-situ hybridization. Five weeks after birth, cystic forms were detected in four neonatal rats. In the lobes of the lungs, no predilection site of P. carinii was recognized. Counts of cystic forms on smears and the reactivity of in-situ hybridization in the lungs of neonatal rats were significantly lower than in maternal rats. The present findings suggest that P. carinii is rarely transmitted through the placenta and proliferates less successfully in the lungs of neonatal rats than in mothers.
Animal ; Animals, Newborn/microbiology* ; Disease Transmission, Vertical* ; Female ; Immunocompromised Host ; Lung/microbiology ; Male ; Opportunistic Infections/transmission* ; Opportunistic Infections/complications ; Pneumocystis carinii/isolation & purification ; Pneumonia, Pneumocystis carinii/transmission* ; Pneumonia, Pneumocystis carinii/complications ; Pregnancy ; Rats ; Rats, Wistar

The purpose of this study was to evaluate the capacity of a lactic acid bacteria (LAB) inoculum to protect calves with or without lactose supplements against Salmonella Dublin infection by evaluating histopathological lesions and pathogen translocation. Fifteen calves were divided into three groups [control group (C-G), a group inoculated with LAB (LAB-G), and a group inoculated with LAB and given lactose supplements (L-LAB-G)] with five, six, and four animals, respectively. The inoculum, composed of Lactobacillus (L.) casei DSPV 318T, L. salivarius DSPV 315T, and Pediococcus acidilactici DSPV 006T, was administered with milk replacer. The LAB-G and L-LAB-G received a daily dose of 109 CFU/kg body weight of each strain throughout the experiment. Lactose was provided to the L-LAB-G in doses of 100 g/day. Salmonella Dublin (2 x 1010 CFU) was orally administered to all animals on day 11 of the experiment. The microscopic lesion index values in target organs were 83%, 70%, and 64.3% (p < 0.05) for the C-G, LAB-G, and L-LAB-G, respectively. Administration of the probiotic inoculum was not fully effective against infection caused by Salmonella. Although probiotic treatment was unable to delay the arrival of pathogen to target organs, it was evident that the inoculum altered the response of animals against pathogen infection.
Administration, Oral ; Animals ; Animals, Newborn ; Cattle ; Cattle Diseases/*drug therapy/microbiology/pathology ; Dietary Supplements/*analysis ; Feces/microbiology ; Lactobacillus/metabolism ; Lactose/*metabolism ; Male ; Pediococcus/metabolism ; Probiotics/*therapeutic use ; Salmonella Infections, Animal/*drug therapy/microbiology/pathology ; Salmonella enterica/*drug effects/growth & development ; Tissue Distribution

OBJECTIVETo investigate the expression of glial fibrillary acidic protein (GFAP), GFAP mRNA and interleukin-1beta mRNA (IL-1beta mRNA), tumor necrosis factor-alpha mRNA (TNF-alpha mRNA) in neonatal rat brain after intrauterine infection.

METHODSEscherichia coli (E. coli) was inoculated into both uterine horns of pregnant rats when gestation was 70% complete (15 days). The control group was treated with normal saline. The pups were killed on the postnatal day 1 (P1), P3 and P7, respectively. The cerebral white matter damage of the neonatal rats was determined by HE staining. Immunohistochemistry was used for evaluation of GFAP expression in neonatal rat brains and RT-PCR to analyze GFAP mRNA, IL-1beta mRNA and TNF-alpha mRNA expression at P1, P3 and P7.

RESULTSThe major histopathological changes in neonatal cerebral white matter at P7 after intrauterine infections were: weak staining of cerebral white matter and focal rarefaction. GFAP-positive cells were observed in both the control and the E. coli-treated groups. The numbers of GFAP-positive cells of the E. coli-treated group pups were markedly increased in periventricular white matter and hippocampus at P7 compared with those of the control group (periventricular white matter: 9.73 +/- 3.55 vs 5.67 +/- 1.90, P < 0.05 and hippocampus: 7.81 +/- 3.61 vs 2.16 +/- 1.11, P < 0.05, respectively). No significantly different levels of GFAP expression in corpus callosum were found between two groups (P > 0.05). The expression of GFAP mRNA in brain of the E. coli-treated neonatal rat was higher than the control at P1, P3 (P1: 0.25 +/- 0.07 vs 0.15 +/- 0.08, P < 0.05 and P3: 0.50 +/- 0.09 vs 0.39 +/- 0.08, P < 0.05, respectively), but the expression of GFAP mRNA in brain of the neonatal rat at P7 had no significant difference between two groups (P > 0.05). The expression of IL-1beta mRNA and TNF-alpha mRNA in brain of the E. coli-treated neonatal rat were higher than of the control at P1 (IL-1beta mRNA: 0.83 +/- 0.19 vs 0.50 +/- 0.30, P < 0.05 and TNF-alpha mRNA: 0.74 +/- 0.30 vs 0.30 +/- 0.20, P < 0.05, respectively), but the expression of IL-1beta mRNA and TNF-alpha mRNA in brain of the neonatal rat at P3 and P7 had no significant difference between two groups (P > 0.05).

CONCLUSIONSThe intrauterine infection could cause neonatal white matter damage and IL-1beta, TNF-alpha may be a mechanism mediating between the two events.

Animals ; Animals, Newborn ; Brain ; metabolism ; pathology ; Disease Models, Animal ; Escherichia coli Infections ; microbiology ; physiopathology ; Female ; Glial Fibrillary Acidic Protein ; analysis ; genetics ; Immunohistochemistry ; Interleukin-1 ; genetics ; Pregnancy ; Pregnancy Complications, Infectious ; microbiology ; physiopathology ; RNA, Messenger ; metabolism ; Rats ; Reverse Transcriptase Polymerase Chain Reaction ; Tumor Necrosis Factor-alpha ; genetics ; Uterus ; microbiology