Exploiting Fluorescence Lifetime Plasticity in FLIM: Target Molecule Localization in Cells and Tissues

The mechanisms of drug-receptor interactions and the controlled delivery of drugs via biodegradable and biocompatible nanoparticulate carriers are active research fields in nanomedicine. Many clinically used drugs target G-protein coupled receptors (GPCRs) due to the fact that signaling via GPCRs is crucial in physiological and pathological processes and thus central for the function of biological systems. In this letter, a fast and reliable ratiometric fluorescence lifetime imaging microscopy (rmFLIM) approach is described to analyze the distribution of protein-ligand complexes in the cellular context. Binding of the fluorescently labeled antagonist naloxone to the G-protein coupled μ-opioid receptor is used as an example. To show the broad applicability of the rmFLIM method, we extended this approach to investigate the distribution of polymer-based nanocarriers in histological liver sections.

Characteristics of police officer suicides in the Federal Austrian Police Corps

BACKGROUND

Suicide rates among police officers may be high because of strong occupational stressors.

AIMS

This study examined the suicide rate and suicide characteristics among police officers in the Federal Austrian Police Force.

METHODS

All suicides among policemen during the period 1996-2006 were analyzed retrospectively on the basis of personalized police record files from all Austrian police departments. Information on sex, age, marital status, children, region, method and place of suicide, suicide notes, position, and length of service was extracted from these files. The general Austrian population, adjusted for sex and age composition, served as the comparison group.

RESULTS

The suicide rate among male police officers was 30.2/100,000 (SD 11.0), which was comparable to the suicide rate in the adjusted general population (30.5/100,000; SD 2.9). The female police officer suicide rate was 1.8/100,000, while the corresponding suicide rate of the adjusted female general population was 12.5/100,000 (SD 1.7). Firearms were the most frequent suicide method (77.8%), and the incidence of suicide notes was 30.8%.

CONCLUSIONS

Suicide rates among police officers seem comparable to those of the age-adjusted general population. Given the healthy-worker effect, these results still suggest an increased risk of suicide among police officers. These findings should stimulate further research on stressors and risk factors for suicide among officers and should also encourage departments to increase awareness regarding suicidal signs among officers.

Estimating the global burden of foodborne diseases--a collaborative effort

Illness and death from diseases caused by unsafe food are a constant threat to public health security as well as socio-economic development throughout the world. The full extent of the burden and cost of foodborne diseases associated with pathogenic bacterial, viral and parasitic microorganisms, and food contaminated by chemicals is still unknown but is thought to be substantial. The World Health Organization (WHO) Initiative to estimate the global burden of foodborne diseases aims to fill the current data gap and respond to the increasing global interest in health information. Collaborative efforts are required to achieve the ambitious task of assessing the foodborne disease burden from all causes worldwide. Recognising the need to join forces, the WHO Initiative has assembled an alliance of stakeholders which share and support the Initiative's vision, intended objectives and outcomes. One important collaborator is the European Centre for Disease Prevention and Control (ECDC) which has embarked on a burden of disease study covering at least 18 foodborne diseases in nearly 30 countries.

Antinociception by neutrophil-derived opioid peptides in noninflamed tissue--role of hypertonicity and the perineurium

Inflammatory pain can be controlled by intraplantar opioid injection or by secretion of endogenous opioid peptides from leukocytes in inflamed rat paws. Antinociception requires binding of opioid peptides to opioid receptors on peripheral sensory nerve terminals. In the absence of inflammation, hydrophilic opioid peptides do not penetrate the perineurial barrier and, thus, do not elicit antinociception. This study was designed to examine the conditions under which endogenous, neutrophil-derived hydrophilic opioid peptides (i.e. Met-Enkephalin and beta-endorphin) can raise nociceptive thresholds in noninflamed tissue in rats. Intraplantar injection of the chemokine CXCL2/3 (macrophage inflammatory protein-2) induced selective neutrophil recruitment without overt signs of inflammation or changes in mechanical nociceptive thresholds (paw pressure threshold). Following intraplantar injection of hypertonic saline, the perineurial barrier was permeable for hours and intraplantar injection of opioid peptides increased mechanical nociceptive thresholds. While formyl-Met-Leu-Phe (fMLP) triggered opioid peptide release from neutrophils in vitro, nociceptive thresholds were unchanged in vivo. In vitro, hypertonicity interfered with fMLP-induced p38 mitogen activated kinase (MAPK) phosphorylation and opioid peptide release from neutrophils. These inhibitory effects were fully reversible by washout. In vivo, return to normotonicity occurred within 30min while the perineurium remained permeable for hours. Under these conditions, fMLP triggered MAPK phosphorylation and induced opioid peptide-mediated increases in nociceptive thresholds in the noninflamed paw. Taken together, antinociception mediated by endogenous opioids in noninflamed tissue has two important requirements: (i) opening of the perineurial barrier for opioid peptide access and (ii) opioid peptide release from neutrophils involving p38 MAPK.

[Opioids in musculoskeletal pain]

Opioids are the most potent analgesics available and are well established for the treatment of severe acute, surgical and cancer pain. Due to their high effectiveness, their use in chronic non-cancer pain (CNCP) is being propagated. However, the use of opioids is still controversial due to their side effects, such as tolerance, addiction or withdrawal, and administrative difficulties associated with their prescription. Chronic rheumatic diseases, in particular low back pain and arthritis, are the leading causes of CNCP. The present article provides a brief overview of the role of opioids in chronic rheumatic diseases, pointing out that a national guideline for opioid use in CNCP is expected at the end of 2008. Furthermore, the peripheral effects of opioids on pain and inflammation in rheumatic diseases will be outlined.

SAR studies on a novel series of human cytomegalovirus primase inhibitors

A novel series of imidazolylpyrimidines were found to possess inhibitory activity against the human CMV UL70 primase. Extensive SAR studies on an HTS lead led to potent, orally bioavailable compounds with anti-CMV IC(50) values of 150 nM in both viral yield and viral DNA replication assays and with a much reduced cytotoxicity compared to marketed treatments ganciclovir and cidofovir.

Opioids

Opioids are the most effective and widely used drugs in the treatment of severe pain. They act through G protein-coupled receptors. Four families of endogenous ligands (opioid peptides) are known. The standard exogenous opioid analgesic is morphine. Opioid agonists can activate central and peripheral opioid receptors. Three classes of opioid receptors (mu, delta, kappa) have been identified. Multiple pathways ofopioid receptor signaling (e.g., G(i/o) coupling, cAMP inhibition, Ca++ channel inhibition) have been described. The differential regulation of effectors, preclinical pharmacology, clinical applications, and side effects will be reviewed in this chapter.

Further evidence of pleiotropy influencing speech and language: analysis of the DYX8 region

BACKGROUND/AIMS

Genetic studies have raised the possibility of common bases for cognitive linguistic disorders such as speech sound disorder (SSD), reading disorder (RD) and language impairment (LI). Thus, some of the same genes may jointly influence cognitive components within and between these three disorders. We examined the plausibility of this theory in a sample of families ascertained on the basis of a child with SSD.

METHODS

Using the method of generalized estimating equations to solve a bivariate family predictive model we obtained measures of comorbidity and familial aggregation of SSD and LI. We then used two methods of multipoint model-free linkage analysis to evaluate SSD and LI psychometric test measures over a region previously implicated in linkage studies of RD, DYX8 region, 1p34-p36.

RESULTS

Bivariate phenotypic analyses show evidence of comorbidity and within family aggregation and coaggregation of SSD and LI. In addition, two regions on chromosome 1 show suggestive evidence of linkage. The first region was previously reported in dyslexia studies. Our maximum linkage signal in this region measured articulation (p = 0.0009) in SSD sibling pairs. The second region is characterized by processes involved in language production, with the maximum linkage signal measuring listening comprehension (p = 0.0019) using all sibling pairs.

CONCLUSION

We conclude that the DYX8 region could bear genes controlling pleiotropic effects on SSD, LI and RD.

Discovery of a novel series of inhibitors of human cytomegalovirus primase

Infection by human cytomegalovirus (hCMV) remains a potent threat to susceptible people throughout the world. We have discovered a series of imidazolyl-pyrimidine compounds, which were found to be irreversible inhibitors of the hCMV UL70 primase based on results from radiolabeling and SAR studies. Two promising analogs are described that rival ganciclovir and cidofovir in antiviral potency and possess improved cytotoxicity profiles.

Interleukin-1 beta contributes to the upregulation of kappa opioid receptor mrna in dorsal root ganglia in response to peripheral inflammation

During local painful inflammation, axonal transport of opioid receptors from dorsal root ganglia toward the periphery is increased, associated with a higher receptor density and enhanced efficacy of opioid analgesics at the injured site. To examine whether this increase is related to transcription, mRNA of the kappa opioid receptor in lumbar dorsal root ganglia was quantified by real time light cycler polymerase chain reaction. In dorsal root ganglia of naive rats, kappa opioid receptor mRNA expression was three-fold higher than previously shown for delta opioid receptor and two times lower than mu opioid receptor mRNA, respectively. After induction of unilateral paw inflammation by Freund's complete adjuvant, kappa opioid receptor mRNA was significantly upregulated with a peak at 12 h in ipsilateral dorsal root ganglia. This effect could be mimicked by intraplantar injection of the proinflammatory cytokine interleukin-1 beta. Kappa opioid receptor mRNA upregulation lasted longer in interleukin-1 beta-treated rats compared with Freund's complete adjuvant-treated rats. Furthermore, a significant increase in kappa opioid receptor positive neurons was detected by immunohistochemistry 24 h after local injection of Freund's complete adjuvant or interleukin-1 beta. In Freund's complete adjuvant-induced inflammation, kappa opioid receptor upregulation was blocked by treatment with interleukin-1 receptor antagonist without changing the leukocyte infiltration in the paw. In conclusion, kappa opioid receptor mRNA and protein in dorsal root ganglia are upregulated in response to peripheral inflammation. This effect can be mimicked by a single local injection of interleukin-1 beta, and Freund's complete adjuvant-induced upregulation in kappa opioid receptor mRNA and protein can be prevented by treatment with interleukin-1 receptor antagonist. These data suggest that the peripheral production of the proinflammatory cytokine interleukin-1 beta is a specific inducer of kappa opioid receptor expression in the dorsal root ganglia.

Leukocytes in the regulation of pain and analgesia

When tissue is destroyed or invaded by leukocytes in inflammation, numerous mediators are delivered by the circulation and/or liberated from resident and immigrated cells at the site. Proalgesic mediators include proinflammatory cytokines, chemokines, protons, nerve growth factor, and prostaglandins, which are produced by invading leukocytes or by resident cells. Less well known is that analgesic mediators, which counteract pain, are also produced in inflamed tissues. These include anti-inflammatory cytokines and opioid peptides. Interactions between leukocyte-derived opioid peptides and opioid receptors can lead to potent, clinically relevant inhibition of pain (analgesia). Opioid receptors are present on peripheral endings of sensory neurons. Opioid peptides are synthesized in circulating leukocytes, which migrate to inflamed tissues directed by chemokines and adhesion molecules. Under stressful conditions or in response to releasing agents (e.g., corticotropin-releasing factor, cytokines, noradrenaline), leukocytes can secrete opioids. They activate peripheral opioid receptors and produce analgesia by inhibiting the excitability of sensory nerves and/or the release of excitatory neuropeptides. This review presents discoveries that led to the concepts of pain generation by mediators secreted from leukocytes and of analgesia by immune-derived opioids.

Topische Applikation von Morphingel bei entzündlichen Haut- und Schleimhautläsionen

AIM

The aim of this study was to demonstrate a peripheral local opioid effect using case examples involving inflammatory mucosal and cutaneous lesions.

METHODS

A 0.1% morphine gel, mixed in the hospital pharmacy, was applied several times daily to inflammatory mucosal lesions (oral, anogenital and in one patient to a skin ulcer). The effects and side effects were documented.

RESULT

All patients experienced a significant reduction in pain with the use of topical morphine gel and no side effects were seen.

CONCLUSION

Topical peripheral application of morphine gel is a simple, effective method that can be carried out by patients several times a day with few side effects.

Topische Applikation von Lokalanästhetika und Opioiden nach elektiver Zahnextraktion

The aim of this study was to provide evidence for the peripheral effect of opioids in oromaxillary procedures and to investigate whether postoperative morphine sulfate plus lidocaine administered as a local spray achieve better analgesic efficacy than lidocaine applied alone. The double-blind randomized study included 60 patients. The patients exhibited neither preoperative pain nor inflammation (tooth extractions) and when pain occurred received as alternative medication diclofenac retard 50 mg or tramadol. Side effects were documented. No differences between the two groups were observed in the demographic data, visual and numeric analog scale in the first 24 h, or in the consumption of analgesics. Since the patients presented in a pain-free state at the time of surgery, apparently no activation of the peripheral opioid receptors occurs. Thus, a peripheral effect of opioids could not be demonstrated in this model.