Type I interferon and interferon-stimulated gene expression in oral epithelial cells.

Oral epithelial cells (OEC) represent the first site of host interaction with viruses that infect the body through the oral route; however, their innate antiviral defense mechanisms yet to be defined. Previous studies have determined that OEC express pathogen-, damage-, or danger-associated molecular patterns (PAMPs or DAMPs), but their expression of key antiviral innate immune mediators, including type I interferons (type I IFN) and interferon-stimulated genes (ISGs) has not been studied extensively. We used the oral keratinocyte cell line, OKF6/TERT1, in the presence and absence of the viral mimics poly(I:C) and unmethylated CpG DNA, to define the expression of type I IFN and ISGs. We identified the basal expression of novel type I IFN genes IFNE and IFNK, while IFNB1 was induced by viral mimics, through the nuclear translocation of IRF3. Numerous ISGs were expressed at basal levels in OEC, with an apparent correlation between high expression and antiviral activity at the earlier stages of viral infection. Stimulation of OECs with poly(I:C) led to selective induction of ISGs, including MX1, BST2, PML, RSAD2, ISG15, and ZC3HAV1. Together, our results demonstrate that OECs exhibit a robust innate antiviral immune defense profile, which is primed to address a wide variety of pathogenic viruses that are transmitted orally.

Beta-defensins: what are they really doing in the oral cavity?

Initially identified as broad-spectrum antimicrobial peptides, the members of the ß-defensin family have increasingly been observed to exhibit numerous other activities, both in vitro and in vivo, that do not always relate directly to host defense. Much research has been carried out in the oral cavity, where the presence of commensal bacteria further complicates the definition of their role. In addition to direct antimicrobial activity, ß-defensins exhibit potent chemotactic activity for a variety of innate immune cells, as well as stimulating other cells to secrete cytokines. They can also inhibit the inflammatory response, however, by the specific binding of microbe-associated molecular patterns. These patterns are also able to induce the expression of ß-defensins in gingival epithelial cells, although significant differences are observed between different species of bacteria. Together these results suggest a complex model of a host-defense related function in maintenance of bacterial homeostasis and response to pathogens. This model is complicated, however, by numerous other observations of ß-defensin involvement in cell proliferation, wound healing and cancer. Together, the in vitro, in vivo and human studies suggest that these peptides are important in the biology of the oral cavity; exactly how is still subject to speculation.

Long-term outcome following selective serotonin reuptake inhibitor induced neonatal abstinence syndrome.

OBJECTIVE: To assess the long-term neurodevelopment of children exposed in utero to selective serotonin reuptake inhibitors (SSRIs) that developed a neonatal abstinence syndrome (NAS). STUDY DESIGN: Neurodevelopmental evaluation was performed at the age of 2 to 6 years. Children who developed NAS were compared with those who did not using univariate and logistic regression analyses. RESULT: Thirty children with NAS and 52 without NAS participated in the study. Both groups were similar in mean cognitive ability (106.9±14.0 vs 100.5±14.6, P=0.12) and developmental scores (98.9±11.4 vs 95.7±9.9, P=0.21). However, there was a trend towards small head circumference in the NAS group (20 vs 6%, P=0.068). NAS was associated with an increased risk of social-behavior abnormalities (odds ratio (OR) 3.03, 95% confidence interval (CI) 1.07 to 8.60, P=0.04) and advanced maternal age (OR 1.12, 95% CI 1.00 to 1.25, P=0.04). CONCLUSION: Infants who developed NAS had normal cognitive ability, but were at an increased risk for social-behavioral abnormalities. Follow-up evaluation of symptomatic neonates should be considered.

Activity of antimicrobial peptide mimetics in the oral cavity: I. Activity against biofilms of Candida albicans.

Naturally occurring antimicrobial peptides hold promise as therapeutic agents against oral pathogens such as Candida albicans but numerous difficulties have slowed their development. Synthetic, non-peptidic analogs that mimic the properties of these peptides have many advantages and exhibit potent, selective antimicrobial activity. Several series of mimetics (with molecular weight < 1000) were developed and screened against oral Candida strains as a proof-of-principle for their antifungal properties. One phenylalkyne and several arylamide compounds with reduced mammalian cytotoxicities were found to be active against C. albicans. These compounds demonstrated rapid fungicidal activity in liquid culture even in the presence of saliva, and demonstrated synergy with standard antifungal agents. When assayed against biofilms grown on denture acrylic, the compounds exhibited potent fungicidal activity as measured by metabolic and fluorescent viability assays. Repeated passages in sub-minimum inhibitory concentration levels did not lead to resistant Candida, in contrast to fluconazole. Our results demonstrate the proof-of principle for the use of these compounds as anti-Candida agents, and their further testing is warranted as novel anti-Candida therapies.

Activity of antimicrobial peptide mimetics in the oral cavity: II. Activity against periopathogenic biofilms and anti-inflammatory activity.

Whereas periodontal disease is ultimately of bacterial etiology, from multispecies biofilms of gram-negative anaerobic microorganisms, much of the deleterious effects are caused by the resultant epithelial inflammatory response. Hence, development of a treatment that combines anti-biofilm antibiotic activity with anti-inflammatory activity would be of great utility. Antimicrobial peptides (AMPs) such as defensins are naturally occurring peptides that exhibit broad-spectrum activity as well as a variety of immunomodulatory activities. Furthermore, bacteria do not readily develop resistance to these agents. However, clinical studies have suggested that they do not represent optimal candidates for exogenous therapeutic agents. Small-molecule mimetics of these AMPs exhibit similar activities to the parent peptides, in addition to having low toxicity, high stability and low cost. To determine whether AMP mimetics have the potential for treatment of periodontal disease, we examined the activity of one mimetic, mPE, against biofilm cultures of Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis. Metabolic assays as well as culture and biomass measurement assays demonstrated that mPE exhibits potent activity against biofilm cultures of both species. Furthermore, as little as 2 µg ml(-1) mPE was sufficient to inhibit interleukin-1ß-induced secretion of interleukin-8 in both gingival epithelial cells and THP-1 cells. This anti-inflammatory activity is associated with a reduction in activation of nuclear factor-κB, suggesting that mPE can act both as an anti-biofilm agent in an anaerobic environment and as an anti-inflammatory agent in infected tissues.

A near-infrared (NIR) technique for imaging food materials.

The results of imaging experiments in food materials are presented, using near-infrared wavelengths. The technique uses a modulated source and a lock-in amplifier detection circuit to give a high sensitivity to changes in through-transmission signal levels. This is shown to lead to a set of images, whereby the internal content of various foods can be imaged. Examples are presented of the detection of foreign bodies, both metallic and nonmetallic, to illustrate the imaging performance.

Host defense peptides in the oral cavity and the lung: similarities and differences.

Peptides with broad-spectrum antimicrobial activity are found in the mucosal surfaces at many sites in the body, including the airway, the oral cavity, and the digestive tract. Based on their in vitro antimicrobial and other immunomodulatory activities, these host defense peptides have been proposed to play an important role in the innate defense against pathogenic microbial colonization. The genes that encode these peptides are up-regulated by pathogens, further supporting their role in innate immune defense. However, the differences in the local microbial environments between the generally sterile airway and the highly colonized oral cavity suggest a more complex role for these peptides in innate immunity. For example, beta-defensin genes are induced in the airway by all bacteria and Toll-like receptor (TLR) agonists primarily through an NF-kappaB-mediated pathway. In contrast, the same genes are induced in the gingival epithelium by only a subset of bacteria and TLR ligands, via different pathways. Furthermore, the environments into which the peptides are secreted--specifically saliva, gingival crevicular fluid, and airway surface fluid--differ greatly and can effect their respective activities in host defense. In this review, we examine the differences and similarities between host defense peptides in the oral cavity and the airway, to gain a better understanding of their contributions to immunity.

Differential regulation of innate immune response genes in gingival epithelial cells stimulated with Aggregatibacter actinomycetemcomitans.

BACKGROUND AND OBJECTIVE: The gingival epithelium provides the first line of defense against colonization by periodontal pathogens, both as a physical barrier and by the production of inducible innate immune mediators such as beta-defensins and pro-inflammatory cytokines. The gram-negative bacterium Aggregatibacter actinomycetemcomitans is implicated in the pathogenesis of localized aggressive periodontitis, although the bacterium is found widely in the healthy population. We hypothesized that gingival epithelial cell-derived innate immune mediators triggered in response to A. actinomycetemcomitans infection may play an important role in increased susceptibility to infection. MATERIAL AND METHODS: Primary cultures of human gingival epithelial cells were cultured in the presence of A. actinomycetemcomitans. Total mRNA was examined for the presence of innate immune markers using RT-PCR. RESULTS: We show here that the mRNA levels of human beta-defensin 2 and interleukin-8 are elevated by live cultures of a clinical isolate of A. actinomycetemcomitans in cultured gingival epithelial cells from healthy individuals, but not by A. actinomycetemcomitans lipopolysaccharide. Cells from a patient with localized aggressive periodontitis, however, did not respond to this bacterial stimulation. In contrast, the pro-inflammatory cytokine interleukin-19 was induced in cells from both localized aggressive periodontitis and healthy subjects. Examination of Toll-like receptors and associated adapter molecules indicated lower levels of Toll-like receptor 2 mRNA in the localized aggressive periodontitis patient-derived cells compared with cells from healthy subjects. CONCLUSION: These results suggest that a differential expression of innate immune response genes to A. actinomycetemcomitans in the gingival epithelium could be an underlying factor of susceptibility to localized aggressive periodontitis.

Variations of mitochondrial DNA sequence in three breeds of rabbit (Oryctolagus cuniculus).

Sequencing of the 300 bp region of the mitochondrial cytochrome b gene was done. Genetic analysis was carried out for the first time in three exotic breeds (Giant White, Soviet Chinchilla, and German Angora) of European rabbit (Oryctolagus cuniculus) to determine intra- and interspecific variability and to measure the genetic distance. The frequencies of types of mutations (transition, transversion, deletion, and insertion) were also determined. This study throws light on matrilineage of breeds that arise due to interbreed crosses and the genetic management of a stocked rabbit breeding population.

In vivo beta-defensin gene expression in rat gingival epithelium in response to Actinobacillus actinomycetemcomitans infection.

BACKGROUND AND OBJECTIVE: Human beta-defensins have been identified in the oral cavity and are predicted to play a role in the defense against pathogenic bacteria. Homologous rat beta-defensins (RBDs) have been identified, but their expression in the oral cavity has not been examined. Therefore, the aim of this study was to investigate the expression of innate immune mediators in the rat gingival epithelium. MATERIAL AND METHODS: Rats were pretreated with antibiotics to depress the normal oral flora, followed by the introduction of Actinobacillus actinomycetemcomitans in their food to allow colonization and the development of periodontal disease. At various time points, animals were killed and the gingival epithelium was extracted. Semiquantitative reverse transcription-polymerase chain reaction was performed to measure RBD and Toll-like receptor (TLR) mRNA levels. RESULTS: Three beta-defensins (RBD-1, -2 and -5) and two TLRs (TLR-3 and -4) are expressed in normal rat gingival epithelium. After the introduction of A. actinomycetemcomitans, RBD-1 and RBD-2 mRNA levels increased for the first week followed by a return to basal levels. No change in TLR mRNA levels was observed. CONCLUSION: The rat model provides a good system for experimental analysis of the innate immune response to periopathogenic bacteria in the oral cavity, as well as the potential role of beta-defensins in the host response to colonization.

Antimicrobial peptides in the airway.

The airway provides numerous defense mechanisms to prevent microbial colonization by the large numbers of bacteria and viruses present in ambient air. An important component of this defense is the antimicrobial peptides and proteins present in the airway surface fluid (ASF), the mucin-rich fluid covering the respiratory epithelium. These include larger proteins such as lysozyme and lactoferrin, as well as the cationic defensin and cathelicidin peptides. While some of these peptides, such as human beta-defensin (hBD)-1, are present constitutively, others, including hBD2 and -3 are inducible in response to bacterial recognition by Toll-like receptor-mediated pathways. These peptides can act as microbicides in the ASF, but also exhibit other activities, including potent chemotactic activity for cells of the innate and adaptive immune systems, suggesting they play a complex role in the host defense of the airway. Inhibition of antimicrobial peptide activity or gene expression can result in increased susceptibility to infections. This has been observed with cystic fibrosis (CF), where the CF phenotype leads to reduced antimicrobial capacity of peptides in the airway. Pathogenic virulence factors can inhibit defensin gene expression, as can environmental factors such as air pollution. Such an interference can result in infections by airway-specific pathogens including Bordetella bronchiseptica, Mycobacterium tuberculosis, and influenza virus. Research into the modulation of peptide gene expression in animal models, as well as the optimization of peptide-based therapeutics shows promise for the treatment and prevention of airway infectious diseases.

A prevalence estimate of pervasive developmental disorder among immigrants to Israel and Israeli natives- a file review study.

BACKGROUND: The prevalence rates of pervasive developmental disorder (PDD) have risen in the West over the last 10 years. There is argument over the etiology of this change in rates. Social and cultural processes including migration have been hypothesized. Israel, as a country of ongoing immigration with a national registry of children diagnosed with PDD, offers an opportunity to compare rates of PDD among immigrants from developing countries and native Israelis. METHOD: A Social Security national registry of 1004 children diagnosed with PDD was reviewed and rates were calculated using data extracted from the Israel National Bureau of Statistics. Of all Jewish children that were born in the years 1983-1997 and who are currently living in Israel, we defined four groups: (1). native Israelis of non-Ethiopian extraction (N = 1198, 300), (2). native Israelis of Ethiopian extraction (N = 15600), (3). immigrants of non-Ethiopian extraction (N = 110300) and (4). children born in Ethiopia (N = 11800). A further breakdown of groups 1 and 3 by well-characterized ethnic or geographical origins was not possible. RESULTS: The rate of PDD was significantly elevated in native Israelis as compared to all immigrant children. Among immigrants, the rate of PDD in Ethiopian-born children was lower than that of those born in other countries. The rate of PDD in immigrant Ethiopian children was much lower than in native Israeli children of Ethiopian extraction. CONCLUSIONS: Birth in Israel, an industrialized country, is a marker for an environmental risk factor for PDD. This may indicate that gestation, birth or infancy in industrialized countries exposes children to environmental insults that increase the risk for contracting PDD.

Multidimensional family therapy for adolescent drug abuse: results of a randomized clinical trial.

Random assignment was made of 182 clinically referred marijuana- and alcohol-abusing adolescents to one of three treatments: multidimensional family therapy (MDFT), adolescent group therapy (AGT), and multifamily educational intervention (MEI). Each treatment represented a different theory base and treatment format. All treatments were based on a manual and were delivered on a once-a-week outpatient basis. The therapists were experienced community clinicians trained to model-specific competence prior to the study and then supervised throughout the clinical trial. A theory-based multimodal assessment strategy measured symptom changes and prosocial functioning at intake, termination, and 6 and 12 months following termination. Results indicate improvement among youths in all three treatments, with MDFT showing superior improvement overall. MDFT participants also demonstrated change at the 1-year follow-up period in the important prosocial factors of school/academic performance and family functioning as measured by behavioral ratings. Results support the efficacy of MDFT, a relatively short-term, multicomponent, multitarget, family-based intervention in significantly reducing adolescent drug abuse and facilitating adaptive and protective developmental processes.

Natures antibiotics: the potential of antimicrobial peptides as new drugs.

Animals and plants make a variety of substances to prevent potentially lethal infections. These include small antibiotic proteins, or peptides, which target bacteria, fungi and viruses. Research into these peptides not only give us an insight into how we naturally prevent infections, but can also provide us with new drugs to treat the ever-increasing danger of infections caused by antibiotic-resistant bacteria.

Current status of family intervention science.

Looking at the field as a whole through metaanalysis, Shadish et al concluded (based on 162 studies) that marital and family therapies were significantly more effective than no treatment and at least as effective as other forms of psychotherapy. Although these reviews and others are positive, individual studies raise many questions. For instance, based on research findings, family treatments increasingly have become standard care for patients with schizophrenia. It remains unclear what degree and type of family involvement is needed for which patients at which stage of their disorder. In the area of anxiety and depression, there are too few studies to make any strong conclusion. Although investigators such as Barrett, Cobham, and Diamond have produced some positive results, the Lewinsohn and Clark studies fail to demonstrate the added benefit of family involvement. Although Brent's study showed CBT to reduce depression faster, family therapy and supportive therapy did just as well in the long run, and family conflict was a strong risk factor for relapse. In the area of anorexia, Russell and Robins produced strong results from family interventions, whereas Geist found no difference between different types of family interventions. Family treatments for obesity have been inconsistent. In a metaanalysis of 41 studies, parental involvement did not contribute significantly to outcomes. In the Epstein study, however, which included 5- and 10-year follow-up, the results of family intervention were impressive. Although many of these studies can be cited for various methodologic flaws, the most consistent problem is that sample sizes are too small to detect difference between two or more active treatments. The most consistent findings (and most well-done, large studies) that support the efficacy of family-based interventions are done with externalizing problems. Work groups led by Patterson, Eisenstadt, Webster-Stratton, Alexander, and Henggeler all have produced impressive reductions of oppositional and antisocial behavior. Clinical programs that treat these populations without using a family-based intervention as at least a component of a treatment package are seriously ignoring the findings of contemporary intervention science. Programs of research by Henggeler, Szapocznik, and Liddle demonstrate similarly impressive results for substance abusing adolescents. Although preliminary results from the Dennis et al study suggest that various treatment approaches may benefit this population. Family interventions have had less success in reducing ADHD symptoms, yet these psychosocial treatments have been essential in reducing much of the family and school behavior problems associated with this disorder. Many investigators would agree that a combined medication and family treatment approach may be the treatment of choice for children with ADHD. In fact, many studies across various disorders suggest that patients respond best to comprehensive treatment packages, of which a family treatment is at least one component. Although the data are promising, many challenges lie ahead. Although collectively many family intervention studies exist, many disorders lack enough rigorous and large-scale investigations to make any strong conclusions. Kazdin argues that sample sizes of 150 are essential to detect significant differences between active treatments, and few of the reviewed studies include these kinds of patient numbers. Furthermore, not enough committed and sophisticated family treatment researchers have carried out some of the major studies. For example, the Brent study on depression and the Barkley study of ADHD, although testing family approaches, lacked well-developed and published treatment manuals, a demonstration of the necessary expertise to supervise these treatments, and data about training and adherence to these models. Although the absence of expertise limits investigator allegiance biases, treatment development and modification are essential for tailoring family treatments to target family processes specific to each disorder. Investigators such as Patterson and Liddle have invested great effort in rigorously dismantling the treatment process, identifying and refining essential ingredients, and repackaging more potent treatment protocols. This process has paid off well. Programmatic treatment development is needed for many disorders to address myriad questions. What are the essential disorder-specific family processes that should be targeted by interventions? Hostility, criticism, communication, attachment and autonomy, attributional sets, and behavior management are important processes of family life, but each may have more relative importance for specific disorders. With a greater understanding of these processes, treatments could be tailored to target these mechanisms more efficiently and effectively. (ABSTRACT TRUNCATED)

Urinary cadmium elimination as a biomarker of exposure for evaluating a cadmium dietary exposure--biokinetics model.

The Cadmium Dietary Exposure Model (CDEM) utilizes national survey data on food cadmium concentrations and food consumption patterns to estimate dietary intakes in the U.S. population. The CDEM has been linked to a modification of the cadmium biokinetic model of Kjellström and Nordlberg (KNM) to derive predictions of kidney and urinary cadmium that reflect U.S. dietary cadmium intake and related variability. Variability in dietary cadmium intake was propagated through the KNM using a Monte Carlo approach. The model predicts a mean peak kidney cadmium burden of approximately 3.5 mg and a 5th-95th percentile range of 2.2-5.1 mg in males. The corresponding peak renal cortex cadmium concentration in males is 15 microg/g wet cortex (10-22, 5th-95th percentile). Predicted kidney cadmium levels in females were higher than males: 5.1 (3.3-7.6) mg total kidney, 29 (19-43) microg/g wet cortex. Predicted urinary cadmium in males and females agreed with empirical estimates based on the NHANES III, with females predicted and observed to excrete approximately twice the amount of cadmium in urine than males. An explanation for the higher urinary cadmium excretion in females is proposed that is consistent with the NHANES III data as well as experimental studies in humans and animals. Females may absorb a larger fraction of ingested dietary cadmium than males, and this difference may be the result of lower iron body stores in females compared to males. This would suggest that females may be at greater risk of developing cadmium toxicity than males. The predicted 5th-95th percentile values for peak kidney cadmium burden are approximately 60% of the peak kidney burden (8-11 mg) predicted for a chronic intake at the U.S. Environmental Protection Agency (EPA) chronic reference dose of 1 microg/kg-d.

Peripheral arterial responses to treadmill exercise among healthy subjects and atherosclerotic patients.

UNLABELLED: BACKGROUND-Peripheral cutaneous vascular beds, such as the fingertips, contain a high concentration of arteriovenous anastomoses, richly innervated by a-adrenergic nerve fibers, to control heat regulation. Nevertheless, for a variety of technical reasons, finger blood flow responses to exercise have not been well studied in health and disease. Hence, we compared finger pulse-wave amplitude (PWA) responses to exercise among 50 normal volunteers and 57 patients with atherosclerotic coronary artery disease (CAD) using a robust, modified form of volume plethysmography. METHODS AND RESULTS: PWA was quantified for each minute of exercise as a ratio relative to baseline. Exercise PWA responses were compared with clinical, hemodynamic, ECG, and myocardial single photon emission computed tomography parameters. Among normal subjects, 38 (76%) manifested vasodilation throughout exercise and 12 (24%) manifested initial vasodilation followed by vasoconstriction at high heart rate thresholds. None manifested vasoconstriction throughout exercise. By contrast, 20 CAD patients (35%) manifested progressive vasoconstriction from the onset of exercise, and 10 others (18%) manifested vasoconstriction at low heart rate thresholds (P < 0.001 versus normals) after initial vasodilation with exercise. Patients exhibiting vasodilation versus vasoconstriction during exercise had similar clinical and exercise profiles, except for a greater use of ACE inhibitors and a greater level of achieved metabolic equivalents among the former (P<0.05 for both). CONCLUSIONS: Half of our CAD patients manifested diminution in PWA that was consistent with peripheral arterial vasoconstriction during the early phases of treadmill exercise. Such paradoxical vasoconstrictive responses were not observed in normal subjects and, therefore, they may represent generalized vascular pathology secondary to atherosclerosis.

Antimycobacterial agent based on mRNA encoding human beta-defensin 2 enables primary macrophages to restrict growth of Mycobacterium tuberculosis.

Human macrophages are hosts for Mycobacterium tuberculosis, the causative agent of tuberculosis, which killed approximately 1.87 million people in 1997. Human alveolar macrophages do not express alpha- or beta-defensins, broad-spectrum antimicrobial peptides which are expressed in macrophages from other species more resistant to infection with M. tuberculosis. It has been previously reported that M. tuberculosis is susceptible to killing by defensins, which may explain the difference in resistance. Defensin peptides have been suggested as a possible therapeutic strategy for a variety of infectious diseases, but development has been hampered by difficulties in their large-scale production. Here we report the cellular synthesis of human beta-defensin 2 via highly efficient mRNA transfection of human macrophages. This enabled mycobactericidal and mycobacteristatic activity by the macrophages. Although human macrophages are difficult to transfect with plasmid vectors, these studies illustrate that primary macrophages are permissive for mRNA transfection, which enabled expression of a potentially therapeutic protein.