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author:("Li, jiao")
1.  Modulation of food intake by mTOR signaling in the dorsal motor nucleus of vagus in male rats: Focus on ghrelin and nesfatin-1 
Experimental physiology  2013;98(12):10.1113/expphysiol.2013.074930.
Previous studies demonstrate that mTOR signaling in the hypothalamus is involved in the control of energy homeostasis. The aim of this study is to characterize the effect of mTOR signaling in the dorsal motor nucleus of vagus (DMNV) on the energy intake. Phosphor-mTOR was detected in the DMNV neurons and its levels increased by energy deprivation. Rapamycin significantly inhibited mTOR activity and reduced food intake when administrated into 4th ventricle. Exposure of DMNV neurons to ghrelin increased the phosphorylation of mTOR. Fourth ventricle injection of ghrelin significantly increased food intake relative to the control vehicle. Pre-treatment with rapamycin for 15 min attenuated the orexigenic effect of ghrelin. Reduction in the phosphorylation of mTOR was observed following 4th intracerebroventricular injection of nesfatin-1. When administrated by 4th ICV injection, nesfatin-1 suppressed the food intake as compared with the control. The anorexigenic effect of nesfatin-1 was significantly attenuated by pre-treatment with leucine for 15 min. All these studies suggest that mTOR signaling in the DMNV neurons regulates both the nutrient and hormonal signals for the modulation of food intake.
PMCID: PMC3839812  PMID: 23955309
Dorsal vagal complex; ghrelin; nesfatin-1
2.  Oral Microbiota Distinguishes Acute Lymphoblastic Leukemia Pediatric Hosts from Healthy Populations 
PLoS ONE  2014;9(7):e102116.
In leukemia, oral manifestations indicate aberrations in oral microbiota. Microbiota structure is determined by both host and environmental factors. In human hosts, how health status shapes the composition of oral microbiota is largely unknown. Taking advantage of advances in high-throughput sequencing, we compared the composition of supragingival plaque microbiota of acute lymphoblastic leukemia (ALL) pediatric patients with healthy controls. The oral microbiota of leukemia patients had lower richness and less diversity compared to healthy controls. Microbial samples clustered into two major groups, one of ALL patients and another of healthy children, with different structure and composition. Abundance changes of certain taxa including the Phylum Firmicutes, the Class Bacilli, the Order Lactobacillales, the Family Aerococcaceae and Carnobacteriaceae, as well as the Genus Abiotrophia and Granulicatella were associated with leukemia status. ALL patients demonstrated a structural imbalance of the oral microbiota, characterized by reduced diversity and abundance alterations, possibly involved in systemic infections, indicating the importance of immune status in shaping the structure of oral microbiota.
PMCID: PMC4099009  PMID: 25025462
3.  Molecular Characterization of the Microbiota Residing at the Apical Portion of Infected Root Canals of Human Teeth 
Journal of endodontics  2011;37(10):1359-1364.
This study investigated the bacterial communities residing in the apical portion of human teeth with apical periodontitis in primary and secondary infections using a culture-independent molecular biology approach.
Root canal samples from the apical root segments of extracted teeth were collected from 18 teeth with necrotic pulp and 8 teeth with previous endodontic treatment. Samples were processed for amplification via polymerase chain reaction (PCR) and separated with denaturing gradient gel electrophoresis (DGGE). Selected bands were excised from the gel and sequenced for identification.
Comparable to previous studies of entire root canals, the apical bacterial communities in primary infections were significantly more diverse than in secondary infections (p=0.0003). Inter- and intra-patient comparisons exhibited similar variations in profiles. Different roots of the same teeth with secondary infections displayed low similarity in bacterial composition, while an equivalent sample collected from primary infection contained almost identical populations. Sequencing revealed a high prevalence of fusobacteria, Actinomyces sp. and oral Anaeroglobus geminatus in both types of infection. Many secondary infections contained Burkholderiales or Pseudomonas sp. both of which represent opportunistic environmental pathogens.
Certain microorganisms exhibit similar prevalence in primary and secondary infection indicating that they are likely not eradicated during endodontic treatment. The presence of Burkholderiales and Pseudomonas sp. underscores the problem of environmental contamination. Treatment appears to affect the various root canals of multi-rooted teeth differently, resulting in local changes of the microbiota.
PMCID: PMC3415298  PMID: 21924182
Apical periodontitis; endodontic infections; community profiling; polymerase chain reaction; denaturing gradient gel electrophoresis
4.  High-resolution X-ray microdiffraction analysis of natural teeth 
Journal of Synchrotron Radiation  2008;15(Pt 3):235-238.
In situ microzone X-ray diffraction analysis of natural teeth is presented. From our experiment, layer orientation and continuous crystal variations in teeth could be conveniently studied using fast online measurements by high-resolution X-ray microdiffraction equipment.
The main component of natural teeth was determined many years ago as calcium phosphate, mostly in the form of hydroxyapatite with different crystallites. In the past, the method used in tooth crystal investigation has been mainly powder X-ray diffraction analysis, but this method has its drawbacks, i.e. the destruction of the natural tooth structure and the difficulty in examining the preferred orientation in different layers of the tooth. During the last century, microzone X-ray diffraction on the tooth surface was carried out, but, as the technology was less sophisticated, the results obtained were not very detailed. The newly developed microdiffraction equipment permits analysis of the microzone of teeth in situ. To test this new microdiffraction equipment, microdiffraction analysis of one natural healthy deciduous molar tooth and one carious deciduous molar tooth has been performed, using a Bruker D8 instrument. Phase analysis of the two teeth was performed; the crystal size at six test points in the natural healthy tooth was calculated by reflection (211), and the crystal preferred orientation of reflection (300) and reflection (002) at six test points in the natural healthy tooth were compared. The results showed that the tooth was a kind of biological mixed crystal composed of several crystal phases, the main crystal phase being hydroxyapatite. The crystal size grew larger going from the dentin to the enamel. The crystal preferred orientation mainly existed in the enamel, especially in the reflection (002). From our experiment, layer orientation and continuous crystal variations in teeth could be conveniently studied using fast online measurements by high-resolution X-ray microdiffraction equipment.
PMCID: PMC2394821  PMID: 18421147
X-ray microdiffraction; enamel; caries; texture; crystal

Results 1-4 (4)