Characterization and opioid modulation of inflammatory temporomandibular joint pain in the rat.

PURPOSE: Experimental inflammation of the rat temporomandibular joint (TMJ) is commonly used to study trigeminal nociceptive processing. This study describes spontaneous pain-related behaviors following TMJ inflammation in the rat. The ability of preemptive systemic morphine to attenuate behaviors as well as immediate-early gene expression in the trigeminal nucleus is described. MATERIALS AND METHODS: Adult male Sprague-Dawley rats received an intra-articular injection of mustard oil (0% to 20%, 50 microL) and were observed for behavioral changes. Morphine sulfate (0 to 10 mg/kg SC) was given 30 minutes before mustard oil; this was reversed in one group with naltrexone hydrochloride (5 mg/kg SC). Two hours after injection rats were killed and perfused. Immunohistochemistry for the protein product of the immediate-early gene c-fos was performed, and brain stem sections including the trigeminal subnucleus caudalis were examined for positive nuclei. RESULTS: Mustard oil inflammation of the rat TMJ induces dose-dependent, morphine-sensitive behaviors. Behaviors observed included excessive grooming of the region, a chewing-like behavior, and head shaking. Fos expression in the trigeminal subnucleus caudalis parallels changes in behaviors. Morphine dose dependently attenuates the number of behaviors, as well as Fos expression; this effect is reversed by the micro-opioid receptor antagonist naltrexone. CONCLUSIONS: Mustard oil inflammation of the rat TMJ causes reliable behavioral changes, which may be quantified and, together with Fos expression, used to assess various experimental TMJ treatment modalities.     

Evidence of tendinitis provoked by fluoroquinolone treatment: a case-control study.

OBJECTIVE: To investigate the association between the use of fluoroquinolone agents and the risk of tendinitis in a large population-based case-control study. METHODS: The study was performed by linking automated health databases from the Region of Lombardia, Italy. Cases were patients aged > or =18 years who had a hospital discharge diagnosis of non-traumatic tendinitis in 2002-3. For each case, up to five controls were randomly selected among those eligible for inclusion in the study. A conditional logistic regression model was used to estimate the odds ratio of tendinitis associated with the current, recent and past use of fluoroquinolones. Odds ratios were adjusted for exposure to other antibacterials and other drugs. RESULTS: 22,194 cases and 104,906 controls met the inclusion criteria. Current use of fluoroquinolones significantly increased the risk of tendon disorders as a whole (odds ratio [OR] = 1.7; 95% CI 1.4, 2.0), tendon rupture (OR = 1.3; 95% CI 1.0, 1.8) and rupture of the Achilles' tendon (OR = 4.1; 95% CI 1.8, 9.6). Concomitant use of corticosteroids and fluoroquinolones increased the risk of both tendon rupture (OR = 3.1; 95% CI 1.5, 6.3) and rupture of the Achilles' tendon (OR = 43.2; 95% CI 5.5, 341.1). DISCUSSION: Evidence that exposure to fluoroquinolones is associated with the sudden occurrence of tendinitis is supported by this large population-based study. We can estimate that a single case of rupture of the Achilles' tendon would occur for every 5958 persons treated with fluoroquinolones (95% CI 2148, 23,085). The corresponding number needed to harm is 979 (95% CI 122, 9172) for patients who concomitantly use corticosteroids and 1638 (95% CI 351, 8843) for those aged >60 years. CONCLUSION: Clinicians should be aware of this adverse effect, and the increased risk for fluoroquinolone-associated tendinitis in elderly patients with corticosteroid use must be considered when these agents are prescribed.     

Immune control of mammalian aging: a T-cell model.

A competent immune response appears to play an important role in retarding aging. On the other hand, the aged immune system is assumed to accelerate the general aging process. In order to approach the underlying mechanism of this paradoxical immune response, the process of clonal deletion in the thymus is addressed under the aspect of aging. It is assumed that T-cell deletion in the thymus brings about a control of cell differentiation in the organism. For proper functioning, this control is suggested to be directed, in the sense of a feedback mechanism, primarily to thymic stromal cells involved in the process of clonal deletion. At the expense of a thymus atrophy, the control system can retard aging up into the reproductive period of life. With the progress of thymic involution, however, the control is predetermined to undergo a breakdown and, in consequence, through loss of self-tolerance it speeds up the whole aging process.     

Age-related structural and functional changes in the DNA of human lymphocytes

Characteristic changes of DNA winding and repair are detected in human peripheral lymphocytes with advancing donor age between 20 and 90 years, suggesting a progressively undifferentiated cell state. From a model approach it appears likely that the existence of immature lymphocytes favors aging as a general dysdifferentiation of somatic cells.     

Foreign body in the median nerve: a complication of acupuncture

Fracture of an acupuncture needle resulted in a foreign body within the carpal tunnel of a patient who then developed median neuropathy. The needle fragment was recovered from within the median nerve during carpal tunnel release, with rapid post-operative relief of symptoms. Development of peripheral neuropathy is a potential complication of acupuncture.     

Changes in gut bacterial communities in canaries infected by Macrorhabdus ornithogaster

Macrorhabdus ornithogaster is an opportunistic yeast that colonizes the gastric mucosa of many avian species. Until now, no studies have focused on the influence of a gastric infection on the balance of the intestinal microbiota of birds. In this study, 44 faecal samples from individual canaries, with and without M. ornithogaster infection, were analysed. The detection of the yeast was evaluated by 18S rRNA PCR. In order to evaluate the impact of the Macrorhabdus infection on the bacterial communities, culture-independent methods, by the use of amplicon-based sequencing as well as 16S rRNA-DGGE, were adopted. The different health status of animals affected the relative abundance of the main OTUs, with a greater diversification of the gut microbiota in healthy animals compared to the infected. In particular, Lactococcus, Pseudomonas, Acinetobacter, Lachnospiraceae, Propionibacterium and Weissella were found to be characteristic of uninfected animals (FDR?<?0.05), while Lactobacillus and Candidatus Arthromitus were characteristic of infected animals (FDR?<?0.05). Both these taxa have been reported as immunostimulatory, involved in immunological disorders. In infected animals the inferred metagenome assessed by PICRUST clearly showed a positive correlation between the presence of M. ornithogaster and KEGG genes related to ether lipid metabolism, already reported to be immunostimulatory by activation of macrophages and to play a pathophysiological role in several immunological disorders. Finally, our results show an interaction between infection of the digestive tract and intestinal microbiota of pet birds and provide insight into the changing of the complex enteric bacterial community.

• HIGHLIGHTS

• Macrorabdus ornithogaster is a gastric yeast that colonizes a wide range of birds.

• Differences were found between infected and healthy animals in gut microbiota.

• Candidatus Arthromitus was closely associated with infected birds.

• M. ornithogaster can affect intestinal microbiota composition of canaries.

     

Spontaneous activity of dorsal raphe neurons during defensive and offensive encounters in the tree-shrew

The general characteristics of these telemetrically recorded neurons of dorsal raphe, such as firing rate under nembutal anesthesia, reaction to illumination changes or acoustic stimuli were comparable to those in the literature. The firing rate of the dorsal raphe neurons increased during defensive encounters (+51%±29% S.D.; p<0.005) and defensive fights (+113%±91% S.D.; p<0.02) as compared to the neuronal activity of the undisturbed resting animal. The fearful interaction of the animal with the experimenter led to the strongest increase in the firing rate (+187%±114% S.D.; p<0.002) in all animals tested. The offensive animal showed decreased neuronal activity during offensive encounters (?21%±13% S.D.; p<0.02) and offensive fights (?42%±17%S.D.; p<0.05) as compared with the neuronal activity of the undisturbed resting animal. These findings indicate the crucial importance of the animals appraisal of the situational contex for the activity of dorsal raphe neurons.     

Pain in individuals with RASopathies: Prevalence and clinical characterization in a sample of 80 affected patients

Pain in individuals with RASopathies is a neglected topic in literature. In this article, we assessed prevalence and profile of pain in a sample of 80 individuals affected by RASopathies. The study sample included individuals with Noonan syndrome (N = 42), Costello syndrome (N = 17), and cardio‐facio‐cutaneous syndrome (N = 21). A set of standardized questionnaires and scales were administered (VAS/numeric scale, r‐FLACC, Wang‐Baker scale, NPSI, BPI, NCCPC‐R) to detect and characterize acute and chronic pain and to study the influence of pain on quality of life (PEDs‐QL, SF‐36) and sleeping patterns (SDSC); revision of past medical history and multisystemic evaluation was provided. Available clinical data were correlated to the presence of pain. High prevalence of acute (44%) and chronic (61%) pain was documented in the examined sample. Due to age and intellectual disability, acute pain was localized in 18/35 individuals and chronic pain in 33/49. Muscle‐skeletal and abdominal pain was more frequently reported. The intensity of acute and chronic pain interfered with daily activities in 1/3 of the sample. Pain negatively impacted on QoL and sleeping patterns. This work documents that pain is highly prevalent in RASopathies. Future studies including subjective and objective measures of pain are required to discriminate a somatosensory abnormality from an abnormal elaboration of painful stimuli at a central level.     

Congenital infection with human herpesvirus 6 variant B associated with neonatal seizures and poor neurological outcome

Human herpesvirus 6 (HHV 6) has neurotropic and neuroinvasive properties. The virus has been found in the cerebrospinal fluid of many children with aseptic meningoencephalitis. Intrauterine transmission has been documented by HHV 6 DNA detection in cord blood specimens of apparently healthy newborns and in fetuses following spontaneous abortions. A patient is described with early neonatal afebrile seizures resulting from a congenital HHV 6 variant B infection disclosed by repeated detection of viral genome by polymerase chain reaction (PCR) in cerebrospinal fluid in the first days of life. At follow-up, magnetic resonance imaging (MRI) studies disclosed hyperintensities in the periventricular white matter and basal ganglia, associated with cerebral atrophy. Further follow-up at 18 months revealed poor neurological outcome with mild neurodevelopmental retardation, strabismus and hypertonia of legs. This report provides evidence of neurological involvement after HHV 6 vertical transmission, and the association with neurological sequelae.