Nociceptive stimulation activates locus coeruleus neurones projecting to the somatosensory thalamus in the rat

In the thalamus, noradrenergic output from the pontine nucleus locus coeruleus (LC) may actively shape the response properties of various sensory networks en route to the cortex. Little is known, however, about the involvement of ascending noradrenergic innervation of the somatosensory thalamus in the processing of nociceptive information. To address this question, we combined the study of Fos expression upon nociceptive tooth pulp stimulation in the anaesthetized rat, with the detection of retrogradely traced neurones from the somatosensory thalamus. Cell bodies labelled retrogradely from the left thalamus were observed on both sides of the LC, with an ipsilateral predominance ( n = 8). Electrical stimulation of the right incisor pulp ( n = 4) provoked a significantly stronger Fos expression (around twice) than sham surgery ( n = 4), in both the ipsi- and contralateral LC. Significantly larger numbers of double labelled neurones were counted in the LC of tooth-pulp-stimulated animals (representing around 30% of retrogradely labelled cells in LC) than in the LC of sham animals. They were found bilaterally, but with a clear, significant, ipsilateral (i.e. left) predominance. The present data offer an anatomical framework to understand how the LC is involved in the sensory processing of nociceptive information in the thalamus. For the first time, it is shown that nociceptive stimulation activates LC neurones projecting to the somatosensory thalamus. This suggests a new role for LC in modulating nociception within the thalamus.     

Instant and quantitative epoxidation of styrene under ambient conditions over a nickel(ii)dibenzotetramethyltetraaza[14]annulene complex immobilized on amino-functionalized SBA-15

Nickel(ii)dibenzotetramethyltetraaza[14]annulene complex (Nitmtaa) was synthetized and immobilized on post amino-functionalized SBA-15 (N-SBA-15) to obtain a stable and reusable nanocatalyst named as Nitmtaa@N-SBA-15. Here (3-aminopropyl)triethoxysilane (APTES) was first grafted on the surface SBA-15, then Nitmtaa was added and coordinated on the silica surface via APTES amine groups. The structure and morphology, and thermal stability of the prepared nanocatalyst was investigated using SEM, HR-TEM, BET, FT-IR, powder XRD, and TGA. HR-TEM and XRD results revealed a high dispersion of Nitmtaa on the SBA-15 surface. The catalytic activity of this nanocatalyst was evaluated in the epoxidation of styrene, under ambient conditions, using meta-chloroperoxybenzoic acid (m-CPBA) as the oxygen donor. This nanocatalyst showed an immediate and quantitative epoxidation of styrene with high turn-over-frequency ∼31.58 s⁻¹. Moreover, the superior catalytic activity and high stability of Nitmtaa@N-SBA-15 could be maintained after four successive cycles. A possible reaction mechanism is also proposed.

Immediate and quantitative epoxidation of styrene under ambient conditions catalyzed by new nanocatalyst obtained by immobilizing nickel(ii)dibenzotetramethyltetraaza[14]annulene in amino-functionalized SBA-15.     

Soft‐tissue tumor of the perineum: an exceptional case of bilateral perineal myoma

Perineal myomas in female are exceptional. We report the second case in literature of perineal myomas. It is a case of bilateral perineal myomas lifting the skin occurring in a female patient of 49 years old. She was operated by perineal incisions. Histopathology confirmed the fibromatous nature without signs of malignancy.     

Distribution of HLA-B27 and its alleles in patients with reactive arthritis and with ankylosing spondylitis in Tunisia

The purpose of the present study is to investigate the frequency of HLA-B27 and its alleles in reactive arthritis (ReA) and in ankylosing spondylitis (AS) in Tunisia. HLA-B27 alleles were typed by PCR amplification with sequence-specific primers. We studied 17 patients with ReA associated with urethritis or with gastrointestinal infection; 42 HLA-B27-positive patients with AS and 100 healthy controls. Eleven ReA patients (67.7%) were HLA-B27 positive. There was an increased frequencies of HLA-B27 (P = 7.76 × 10⁻¹², OR = 59.30) and a moderate increase of HLA-B51 (P = 0.015; OR = 4.91) alleles in ReA patients when compared with healthy controls. Four B27 subtypes were identified: B*2702, 05, 09 and B*2712. The distribution of these alleles in the ReA patients was 37.5% for B*2702 and B*2705. Only these two subtypes were detected in 18 (42.8%) and 24 (57.1%), respectively, of the AS patients. B*2709 and B*2712 were relatively rare in ReA patients and were identified in one case each. Our results showed a restricted number of HLA-B27 subtypes associated with ReA and AS. B*2702 and 2705 were common in ReA and AS patients.     

Cirrhosis and cirrhogenic diseases in Tunisian children. Multicenter study of 65 cases]

Over a period of 10 years, 65 cases of hepatic cirrhosis and cirrhogenic disease have been observed in five Pediatric Centers in mid Tunisia. The age of the patients ranged from 30 days to 14 years. The main etiology was biliary cirrhosis (24 cases) followed by post-hepatic cirrhosis (15 cases). Eight cases had a metabolic origin, which was Wilson's diseases in five cases. Three children had cirrhosis of a pre-hepatic origin. In 15 children, the liver biopsy showed the presence of cirrhosis but the etiology could not be found. Preventive measures are needed in order to reduce the frequency of cirrhosis among Tunisian children: 1) early recognition of biliary atresia, 2) vaccination against hepatitis B virus of at risk neonates and children, 3) Genetic counselling and search for familial cases when cirrhosis of metabolic origin is identified, particularly Wilson's disease.     

Tunisian health profile: present state and trends

We will try to value the Tunisian Health Profile, its present state and its tendencies. Data have been collected by various sources, in particular international and national organism. The total fertility rate passed from 8 in 1966 to 2.01 in 1999. Besides a light ageing of the population is started (9% of the population are aged of more than 60 years in 1999). Death rates recorded a decrease, mainly of the infantile mortality (140%@1000 in 1966 against 24.7%@1000 in 1999) and the maternal mortality (68.9 per 100,000 living births in 1994 against 220 in 1980-1984). The life expectancy at birth passed from 51 years in 1966 to 72.4 years in 1999. According the morbidity we attend the receding of the majority of transmitted diseases. Resources injected in the system of cares also evolved: The medical density passed from 1 per 6700 inhabitants in 1966 to 1 per 1300 in 1999. Tunisia recorded the most elevated scores for the preventive activities in particular at the vaccinal coverage. The global evolution of the Tunisian health profile is marked by the epidemiological transition buy which pass the country currently. This phase is delicate because it's generating of a growth of care expenses. Decision-makers must be careful to consider advantage priorities and the profitability of the investments.     

Towards a pain treatment based on the identification of the pain-generating mechanisms?

Despite continuous improvements in available pain treatments, many patients with chronic pain still remain insufficiently relieved. Although such therapeutic failures are often ascribed to pharmacological or psychological factors, difficulties in elucidating pain-generating mechanisms may be the main cause of insufficient pain management. These difficulties arise from several origins, including the unsuitability of the usual classification of pain, the exclusive use of etiology or symptom criteria as the main dimension of pain to guide the choice of therapeutic agents, the inadequate interpretation of sensory deficit, the lack of identification of the injured tissues, the absence of objective pain assessment by psychophysical methods. In this paper, we review briefly some fundamental knowledge to determine pain treatment based on the identification of the physiopathological mechanisms of pain. We advocate that once pain-generating mechanisms are known, it becomes possible to establish the appropriate treatment of pain.