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Initial sensing of infection is mediated by germline-encoded pattern-recognition receptors (PRRs), the activation of which leads to the expression of inflammatory mediators responsible for the elimination of pathogens and infected cells. PRRs act as immune sensors that provide immediate cell responses to pathogen invasion or tissue injury. Here, we review the expression of PRRs in human dental pulp cells, namely, receptors from the Toll-like (TLR) and Nod-like NLR families, by which cells recognize bacteria. Particular attention is given to odontoblasts, which are the first cells encountered by pathogens and represent, in the tooth, the first line of defense for the host. Understanding cellular and molecular mechanisms associated with the recognition of bacterial pathogens by odontoblasts is critical for the development of therapeutic strategies that aim at preventing excessive pulp inflammation and related deleterious effects.

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Human odontoblasts are neural crest-derived, dentin-producing mesenchymal cells aligned at the periphery of the dental pulp. They become exposed to cariogenic oral bacteria as these progressively demineralise enamel then dentin to gain access to the pulp. Due to their situation at the dentin-pulp interface, odontoblasts are the first cells encountered by invading pathogens and/or their released components, and represent, in the tooth, the first line of defence for the host. Previous studies have shown that odontoblasts are able to sense pathogens and elicit innate immunity. In particular, they express several pathogen recognition receptors of the Toll-like receptor (TLR) and nucleotide-binding oligomerisation domain (NOD) families, which allow them to recognize specific bacterial and viral components. So far, most studies aiming at elucidating the role of odontoblasts in the dental pulp innate response have focused on Gram-positive bacteria, as these largely dominate the carious microflora in initial and moderate dentin caries lesions. In vitro, odontoblasts were found to be sensitive to Gram-positive bacteria-derived components, mainly lipoteichoic acid which is recognized through cell membrane TLR2. Our studies have shown that engagement of odontoblast TLR2 by LTA triggers TLR2 and NOD2 up-regulation, NF-B nuclear translocation, production of various chemokines including CCL2, CXCL1, CXCL2, CXCL8 and CXCL10, while promoting immature dendritic cell recruitment. Conversely, LTA down-regulates major dentin matrix components, including collagen type I and dentin sialophosphoprotein, as well as TGF-b1, a known inducer of dentin formation. We provide here additional data showing the fine localization of NOD2 in healthy dental pulps, as well as differential regulation of TLR2, TLR4, NOD2, CCL2 and CXCL8 genes by LTA and the synthetic TLR2 agonists Pam2CSK4 and Pam3CSK4. It appears from the aforementioned data that odontoblast-triggered immune events constitute potential targets for interrupting the signaling cascades which lead to excessive immune response and necrosis in the dental pulp tissue challenged with cariogenic bacteria. In particular, preventing Gram-positive bacteria recognition or signal transduction by pattern recognition receptors may represent a valuable strategy to achieve this goal. Future studies in the field will pave the way for designing novel therapeutic agents which modulate odontoblast behaviour to promote pulp healing and repair.

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Hemochromatosis results when the body's iron stores progressively increase. Surplus iron stored in body tissues leads to organ dysfunction and death. Warnings that elevated iron stores increase the risk of cancer development necessitate a review of this condition. Two types of hemochromatosis, hereditary and secondary, are diagnosed in today's hematology-oncology practices. Distinguishing the differences with respect to etiology and management is essential to the risk assessment and long-term nursing management of this patient population.

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PIP: The study purpose was to investigate the suspected relationship between sex guilt and contraceptive use among never married female college students. Specifically, it was thought that there would be a lower level of sex guilt among reliable contraceptors (defined as those females who use oral contraception, the IUD, the diaphragm and/or foam, or whose partners used a condom during the most recent coital experience) than among unreliable contraceptors (those who used no method of birth control or who used withdrawal, the rhythm method or douche). Questionnaires were mailed to 526 female undergraduate students at a large mid-Atlantic land grant university. Students were selected by choosing every 7th name in the student directory. 255 students returned a completed questionnaire (49%). The Mosher Sex Guilt Inventory, Form F, was used to measure the females' present level of sex guilt. 28% were classified as unreliable contraceptors, 27.0% as condom users, and 44.7% as users of reliable "female" methods. 2 independent 1-tailed t tests were performed using separate variance estimates. The females who used a reliable "female" method of contraception had lower guilt scores than the unreliable contraceptors. The difference was statistically significant. Females whose partners used condoms had significantly lower guilt scores than unreliable contraceptors. The findings appeared to support the theoretical idea that acceptance of one's own sexuality, in this instance measured by sex guilt, was related to the use of a reliable form of contraceptive. This relationship appeared to exist whether a female or a male contraceptive method was used.^ieng

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This paper reports the results of a study of the relationship between guilt and sexual behavior among 45 married women. The age breakdown of the subjects included 60 and above, 40 to 50, and 20 to 30, with 15 women included in each age category. A negative relationship was found between the age of subjects and the extent of sexual behavior while a positive relationship existed between age and sexual guilt. The younger women's sexual behavior scores were higher than both the middle and older (statistically significant) women. Scores indicated less guilt associated with sexual behavior for the younger women than for the middle-aged and older (statistically significant) women.

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This study investigated the premarital contraceptive behavior of 222 male and female college students. Contraceptive practice was examined in relation to dating patterns, level of emotional involvement with the sex partner was heightened, the intercourse was planned, and the individual and prior sexual experience.

PIP: In recognition of the evidence that the rate of premarital intercourse is increasing and that a large proportion of those engaging in it are failing to use contraception, the premarital contraceptive behavior of 222 male and female college students was studied in order to learn about the conditions favoring reliable contraceptive use and those that make it unlikely. A pretested self-administered questionnaire was completed by 359 students enrolled in a human sexual development class (137 students were subsequently excluded because they were or had been married, had never had sexual intercourse, or had failed to complete the questionnaire). Contraceptive practice was examined in relation to dating patterns, level of emotional involvement with sex partners, type of birth control used, number of different sex partners, and reasons for failure to use birth control. 1 of the clearest findings of the study was that the beginning participant in intercourse is at high risk. During the 1st intercourse, 20% failed to use any method of contraception and 76% used either none or an unreliable method. By the time of the most recent intercourse, 50% were using the oral contraceptive and an additional 29% were using condom, diaphragm, foam, jelly, IUD, or a combination of these methods. A statistically significant difference was observed between that 1st and most recent intercourse in terms of the usage of reliable contraception. Results showed that the likelihood of using a reliable contraceptive increased when there was a high level of emotional involvement with the sex partner, the intercourse was planned, and the individual had prior sexual experience.

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