Lack of bacterial invasion in experimental periodontitis

The present study in the beagle dog was performed to analyze whether micro-organisms from a subgingival microbiota could be translocated into or had the potential to invade the pocket epithelium and the gingival connective tissue during a phase of rapid breakdown of the attachment apparatus. An attempt was also made to assess whether tetracycline therapy suppressed the subgingival microbiota and changed the size and quality of the lesions in the gingival tissue. 5 inbred beagle dogs were used. Throughout the period of experimentation, the animals were fed a soft diet permitting gross accumulation of plaque and calculus. No mechanical plaque control measures were performed during the course of the study. On day 0, a 120-day period of periodontal tissue breakdown was initiated at the right mandibular 3rd and 4th premolars by tying cotton floss ligatures around the neck of these teeth. The process of tissue breakdown at the mandibular left 3rd and 4th premolars was started 30 days later. The ligatures were replaced once every 2 weeks during the subsequent 4-month period. On experimental day 120, the first biopsy was performed and gingival tissue sections prepared for light and electron microscopic assessment of a series of histometric characteristics. On day 120, a 30-day period of tetracycline (per os) administration was initiated. Each dog was given a dose of 500 mg tetracycline twice daily. On day 150, the biopsy procedure was repeated in the mandibular left premolar regions.(ABSTRACT TRUNCATED AT 250 WORDS)     

Correlates of headache in a population-based cohort of elderly

Data from a community-based study of 3811 persons aged 65 years and older were used to describe the characteristics of headache in the elderly. Subjects were asked whether they experienced headache in the past year, the frequency and severity of their headaches, and whether they experienced three symptoms of migraine: unilaterality, nausea or vomiting, an aura preceding the headache. Prevalence of headache in those aged more than 65 years declined with age in both men and women; women had a higher prevalence in each age group. The same was true for frequent, severe, and migrainous headache. We examined age- and sex-adjusted correlations of headache with several medical and social factors. Prevalence of any headache was strongly associated with joint pain, depression, bereavement, waking during the night, use of eyeglasses, symptoms of temporomandibular joint dysfunction, and self-assessment of health. Similar variables were associated with frequency, severity, and migrainous symptoms, and thus could not be distinguished among these various types.     

Troponin T and I are not reliable markers of cardiac transplant rejection.

OBJECTIVE: Heart transplant recipients undergo a number of invasive endomyocardial biopsies to screen for rejection. Serum assays of troponin T and/or I may provide a less invasive alternative. The purpose of this study was to evaluate troponin T and I as markers of cardiac transplant rejection. METHODS: We conducted a prospective analysis comparing troponin T and I levels to biopsy results in heart transplant recipients. Plasma was assayed for troponin T and I preoperatively, on the first 3 postoperative days, and with each subsequent biopsy. RESULTS: Twenty-nine patients entered the study. A total of 173 biopsies were performed at a mean follow-up of 129+/-9 days (range: 12-564 days). There were two rejection episodes (> or = grade 3), one in each of two patients. There were no significant relationships between troponin T or I and biopsy-proven rejection (> or = grade 3; P=0.59 and 0.54, respectively). There were also no correlations between troponin T or I levels and biopsy grade (P=0.40 and 0.92, respectively). Troponin T and I levels peaked on postoperative day 1 and fell to baseline over long-term follow-up with no peak in serum markers associated with rejection episodes. Donor ischemic time was significantly correlated to troponin T on postoperative days 1-3 (r=0.58, P=0.005; r=0.61, P=0.004; and r=0.61, P=0.003, respectively). CONCLUSIONS: Troponin T and I are not useful indicators of cardiac rejection, but do correlate with donor heart ischemic injury.     

Hemagglutination Inhibition Assay for Gentamicin

A rapid and simple hemagglutination inhibition test for measuring gentamicin concentrations in serum has been developed. Correlation coefficients for this assay with the radioimmunoassay and microbiological assay were r = 710 and r = 0.864, respectively. Measurements of gentamicin levels in serum by the three methods showed no statistically significant differences. The hemagglutination inhibition assay is fast, reliable, and relatively inexpensive, and should prove valuable for laboratory use.     

Determination of CYP2D6 gene copy number by pyrosequencing

BACKGROUND: Identification of CYP2D6 alleles *5 (deletion of the whole CYP2D6 gene) and *2xN (gene duplication) is very important because they are associated with decreased or increased metabolism of many drugs. The most commonly used method for analysis of these alleles is, however, considered to be laborious and unreliable. METHODS: We developed a method to determine the copy number of the CYP2D6*5 and CYP2D6*2xN alleles by use of Pyrosequencing technology. A single set of PCR and sequencing primers was used to coamplify and sequence a region in the CYP2D6 gene and the equivalent region in the CYP2D8P pseudogene, and relative quantification between these fragments was performed. The CYP2D8P-specific Pyrosequencing peak heights were used as references for the CYP2D6-specific peak heights. RESULTS: Analysis of 200 pregenotyped samples showed that this approach reliably resolved 0-4 genome copies of the CYP2D6 gene. In 15 of these samples, the peak pattern from one analyzed position was unexpected but could be solved by conclusive results from a second position. The method was verified on 270 other samples, of which 267 gave results that corresponded to the expected genotype. One of the samples could not be interpreted. The reproducibility of the method was high. CONCLUSIONS: CYP2D6 gene copy determination by Pyrosequencing is a reliable and rapid alternative to other methods. The use of an internal CYP2D8P control as well as generation of a sequence context ensures a robust method and hence facilitates method validation.     

Human NK cells adapt their immune response towards increasing multiplicities of infection of <Emphasis Type="Italic">Aspergillus fumigatus</Emphasis>

Background

The saprophytic fungus Aspergillus fumigatus reproduces by generation of conidia, which are spread by airflow throughout nature. Since humans are inhaling certain amounts of spores every day, the (innate) immune system is constantly challenged. Even though macrophages and neutrophils carry the main burden, also NK cells are regarded to contribute to the antifungal immune response. While NK cells reveal a low frequency, expression and release of immunomodulatory molecules seem to be a natural way of their involvement.

Results

In this study we show, that NK cells secrete chemokines such as CCL3/MIP-1α, CCL4/MIP-1β and CCL5/RANTES early on after stimulation with Aspergillus fumigatus and, in addition, adjust the concentration of chemokines released to the multiplicity of infection of Aspergillus fumigatus.

Conclusions

These results further corroborate the relevance of NK cells within the antifungal immune response, which is regarded to be more and more important in the development and outcome of invasive aspergillosis in immunocompromised patients after hematopoietic stem cell transplantation. Additionally, the correlation between the multiplicity of infection and the expression and release of chemokines shown here may be useful in further studies for the quantification and/or surveillance of the NK cell involvement in antifungal immune responses.

     

Social Relationship Factors,Preoperative Depression,and Hospital Length of Stay in Surgical Patients

Purpose

The interrelated associations of social relationship factors, depression, and outcomes of surgical patients are yet unexplored. The purpose of this study was to investigate whether depression mediates effects of general social support, loneliness, and living alone on hospital length of stay (LOS) of 2487 patients from diverse surgical fields.

Method

Social relationship factors and depression were assessed prior to surgery. The PROCESS macro for SPSS was used to conduct three simple mediation models that tested the indirect effects of social relationship factors on LOS mediated through depression. The models were adjusted for age, gender, preoperative physical health, surgical field, severity of medical comorbidity, and extent of surgical procedure.

Results

Social support and loneliness had significant indirect effects on LOS that were statistically mediated by preoperative depression. Lower social support and the feeling of loneliness were considerably related to higher depression which predicted longer LOS. While social support and loneliness had no direct effects on LOS, there was a small significant direct association of living alone with shorter LOS.

Conclusion

Data suggest that social support and loneliness are indirectly related with surgical outcomes by an association with depression which in turn is related to worse outcomes.

Trial Registration

NCT01357694