Le tétanos nosocomial dans le service de référence de l’hôpital National Donka à Conakry (2001–2011)

Become almost non-existent in the developed countries, the hospital-borne tetanus always stays of current events in our country in spite of the forensic problem which it puts. The objectives of this study were to determine prevalence of this affection, to describe its clinical picture and to determine its lethality. It is about a retrospective study of a duration of 11 years realized in the service of the infectious diseases of Conakry. Among 8649 hospitalizations from 2001 till 2012 we brought together 239 cases of tetanus (2.7%) among which 60 hospital-borne tetanus (0.7%). Men represented 73% of these cases, with a sex-ratio M/F of 2.7. The age bracket of 20–40 years was the most affected with 32 cases (53.3%). A single patient had begun his vaccinal calendar which had remained incomplete. Both national hospitals of the CHU of Conakry and private hospitals were the biggest suppliers of this hospital-borne tetanus with respectively 22 and 27 cases (36.6 and 45%). Tetanus related to IM of quinine represented 26 cases (43.3%) whereas the hernial cure was found in 16 cases (26.6%). The average duration of invasion and incubation was respectively 1.5 days and 6 days for the dead (n = 45.7%) and 2 days and 10.5 days for the survivors. Three-quarters of 60 patients died. The fight against this type of tetanus passes inevitably by an improvement of the working conditions, a strict application of the rules of asepsis and the in-service training of the medical and paramedical staff.     

Update on the management of neuromuscular block: focus on sugammadex

Steroidal neuromuscular blocking agents (NMBAs), such as rocuronium, are widely used in clinical anesthesia and emergency medicine to facilitate endotracheal intubation and artificial ventilation and to allow surgical access to body cavities. Reversal of neuromuscular blockade is important for the acceleration of patient recovery and prevention of postoperative residual neuromuscular blockade and reduces the incidence of severe morbidity and mortality associated with anesthesia management. Sugammadex is the first selective relaxant binding agent (SRBA) and has been designed to reverse the steroidal neuromuscular blocking drug rocuronium. Encapsulation of the rocuronium molecule by sugammadex results in a rapid decrease in free rocuronium in the plasma and subsequently at the nicotinic receptor at the motor endplate. After encapsulation, rocuronium is not available to bind to the nicotinic receptor in the neuromuscular junction. This promotes the liberation of acetylcholine receptors, and muscle activity reappears. This new concept of reversal of neuromuscular block induced by rocuronium (or vecuronium) led to impressive results in animal and phase 1 and 2 studies. Sugammadex is currently in phase 3 clinical studies and may be commercially available by 2008.     

Large‐scale brain network abnormalities in Huntington's disease revealed by structural covariance

Huntington's disease (HD) is a progressive neurodegenerative disorder that can be diagnosed with certainty decades before symptom onset. Studies using structural MRI have identified grey matter (GM) loss predominantly in the striatum, but also involving various cortical areas. So far, voxel‐based morphometric studies have examined each brain region in isolation and are thus unable to assess the changes in the interrelation of brain regions. Here, we examined the structural covariance in GM volumes in pre‐specified motor, working memory, cognitive flexibility, and social‐affective networks in 99 patients with manifest HD (mHD), 106 presymptomatic gene mutation carriers (pre‐HD), and 108 healthy controls (HC). After correction for global differences in brain volume, we found that increased GM volume in one region was associated with increased GM volume in another. When statistically comparing the groups, no differences between HC and pre‐HD were observed, but increased positive correlations were evident for mHD, relative to pre‐HD and HC. These findings could be explained by a HD‐related neuronal loss heterogeneously affecting the examined network at the pre‐HD stage, which starts to dominate structural covariance globally at the manifest stage. Follow‐up analyses identified structural connections between frontoparietal motor regions to be linearly modified by disease burden score (DBS). Moderator effects of disease load burden became significant at a DBS level typically associated with the onset of unequivocal HD motor signs. Together with existing findings from functional connectivity analyses, our data indicates a critical role of these frontoparietal regions for the onset of HD motor signs. Hum Brain Mapp 37:67–80, 2016. © 2015 Wiley Periodicals, Inc.     

Changes in gene expression for GH/PRL/SL family hormones in the pituitaries of homing chum salmon during ocean migration through upstream migration

Gene expression for growth hormone (GH)/prolactin (PRL)/somatolactin (SL) family hormones in the pituitaries of homing chum salmon were examined, because gene expression for these hormones during ocean-migrating phases remains unclear. Fish were collected in the winter Gulf of Alaska, the summer Bering Sea and along homing pathway in the Ishikari River-Ishikari Bay water system in Hokkaido, Japan in autumn. The oceanic fish included maturing adults, which had developing gonads and left the Bering Sea for the natal river by the end of summer. The absolute amounts of GH, PRL and SL mRNAs in the pituitaries of the maturing adults in the summer Bering Sea were 5- to 20-fold those in the winter Gulf of Alaska. The amount of GH mRNA in the homing adults at the coastal seawater (SW) areas was smaller than that in the Bering fish, while the amount of PRL mRNA remained at the higher level until fish arrived at the Ishikari River. The gill Na⁺,K⁺-ATPase activity in the coastal SW fish and the plasma Na⁺ levels in the brackish water fish at the estuary were lowered to the levels that were comparable to those in the fresh water (FW) fish. In conclusion, gene expression for GH, PRL and SL was elevated in the pituitaries of chum salmon before initiation of homing behavior from the summer Bering Sea. Gene expression for GH is thereafter lowered coincidently with malfunction of SW adaptability in the breeding season, while gene expression for PRL is maintained high until forthcoming FW adaptation.     

Characterization of a homologue of mammalian serine racemase from Caenorhabditis elegans: the enzyme is not critical for the metabolism of serine in vivo

Free d ‐serine (d ‐Ser) plays a crucial role in regulating brain function in mammals. In various organisms, including mammals, d ‐Ser is biosynthesized by Ser racemase, a synthetic enzyme that produces d ‐Ser from l ‐Ser. Ser racemase also exhibits dehydratase activity toward several hydroxyamino acids. Thus, this enzyme is unique in that it possesses the capability to both synthesize and degrade d ‐Ser; however, the physiological significance of its degradative activity remains unclear. In contrast to the physiological roles of d ‐Ser in mammals, little is known about the role of this amino acid in lower organisms, including the nematode Caenorhabditis elegans. It is known that a mammalian Ser racemase homologue (T01H8.2) from C. elegans exhibits racemase activity. Here, the enzymatic properties of recombinant T01H8.2 were characterized and compared with those of recombinant human Ser racemase. Furthermore, the levels of several d ‐ and l ‐amino acids were measured in wild‐type C. elegans and in a mutant in which the T01H8.2 gene is partially deleted and thereby inactivated. The results indicate that T01H8.2 also shows dehydratase activity toward several hydroxyamino acids, although the enzyme is not critical for Ser metabolism in vivo. The possible physiological roles of T01H8.2 are discussed.     

Temporal effects of a COX-2-selective NSAID on bone ingrowth

The effects of a short course of a COX-2 inhibitor on bone healing when the drug is discontinued are unknown. We examined the effects of rofecoxib on bone ingrowth over a 6-week period using a well-defined animal model. The Bone Harvest Chamber was implanted bilaterally in mature rabbits. After osseointegration of the chamber, the following treatments were given for 6 weeks each, followed by a harvest in each case: control-no drug; oral rofecoxib (12.5 mg/day) for the first 2 of 6 weeks; washout period-no drug; oral rofecoxib for the last 2 of 6 weeks; washout period-no drug; rofecoxib given continuously for all 6 weeks. Harvested specimens were snap-frozen, cut into serial 6-microm sections, and stained with hematoxylin and eosin and alkaline phosphatase (osteoblast marker), and processed using immunohistochemistry to identify the vitronectin receptor (osteoclast-like cells). Rofecoxib given continuously for 6 weeks yielded statistically less bone ingrowth compared to the control treatment. Rofecoxib given during the initial or final 2 weeks of a 6-week treatment did not appear to interfere with bone ingrowth. This suggests that the effects of COX-2 inhibitors on bone are less profound when the drug is administered for a short period of time.     

Effect of reinsertion of activated nucleus pulposus on disc degeneration: an experimental study on various types of collagen in degenerative discs

We examined the emergence and sequential changes in type I, II, and VI collagen production in an experimental rabbit model of disc degeneration. Type I collagen was minimally present initially and did not change over 24 weeks. Type I collagen seemed to have no effect on the degenerative process in this model. Staining for type II collagen was positive circumferentially in chondrocytelike cells and was mild in the early phase of disc degeneration, when the chondrocytelike cells began to appear in the inner layers of the annulus fibrosus. The stain became stronger during the middle phase when the chondrocytelike cells arranged themselves in cluster. Compared with type II collagen, the staining for type VI collagen was relatively strong early in the degenerative process. These findings led us to speculate that these chondrocytelike cells play an active role in the degenerative process. The reinsertion of nucleus pulposus cells cocultured with annulus fibrosus delayed disc degeneration and the emergence of chondrocytelike cells. Considering that the emergence of chondrocytelike cells which produce type II and type VI collagen is delayed in discs with the injection of cocultured nucleus pulposus cells by annulus fibrosus cells, we conclude that chondrocytelike cells that produce type VI collagen also seems to accelerate degeneration. Type VI collagen is produced at an earlier phase than type II collagen and may be both active agent and a marker for disc degeneration.     

Transmission of schistosomiasis in an urban population and prevalence of intestinal helminthiasis in Bamako, Mali

Parasitological, malacological and anthropological studies were performed to assess the prevalence of Schistosoma haematobium and S. mansoni in schoolchildren living in the suburban area of Bamako. A total of 1017 schoolchildren aged 6-14 years were selected in two different areas between September 1997 and December 1999. In Djikoroni, the prevalence of S. haematobium and S. mansoni was 80.7% (339/420) and 22.8% (85/372) respectively. There was no significant difference of prevalence and intensity of infection with S. haematobium between schools, gender and age (p > 0.05), whereas, those of S. mansoni were higher in the vicinity of (+/- 100 m from) major sites where infected Biomphalaria pfeifferi were found (p < 0.001). In Niomirambougou, S. haematobium was prevalent in 46.7% (279/597) and S. mansoni in 28.2% (134/475). Boys and children aged 11-14 years were more infected (p < 0.001). Associated intestinal helminths (Hymenolepis nana, Necator americanus and Ascaris lumbricoides) were relatively scarce (prevalence < 1%). The prevalences of schistosome infected snails intermediate host were relatively high, 49.3% (100/203) in B. pfeifferi, 20.6% (88/138) in B. truncatus and 24.1% (7/29) in B. globosus. We recorded a total of 2514 water contacts about which 1130 in December and 1384 in January. Most of the children, 42.9% (1077/2511) were attracted to water bodies for bathing, swimming and playing, suggesting the lack of recreational facilities in these areas. Developing local control programmes in schools located in the vicinity of water bodies would contribute to break the parasite transmission cycle in Bamako.