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Initially planned for a 20 year life time, the Onchocerciasis Control Programme in West Africa (OCP) will have finally continued its activities for nearly three decades (vector control alone from 1975 to 1989, then vector control and/or therapeutic treatment until 2002). Although onchocerciasis is no longer a problem of public health importance nor an obstacle to socioeconomic development in the OCP area, the control of this filariasis is not over because OCP never aimed at eradication, neither of the parasite (Onchocerca volvulus), nor of its vector (Simulium damnosum s.l.). In 2003, the eleven Participating countries of OCP will take over the responsibility of carrying out the residual activities of monitoring and the control of this disease. This mission is of great importance because any recrudescence of the transmission could lead in the long run to the reappearance of the clinical signs of onchocerciasis, if not its most serious manifestations. For epidemiological and operational reasons, and given the disparity in national health policies and infrastructures, the capacities of the countries to take over the residual activities of monitoring and control of onchocerciasis are very unequal. Indeed, the interventions to be carried out are very different from one country to another and the process of integrating the residual activities into the national health systems is not taking place at the same pace. This inequality among the countries vis-a-vis the challenges to be met does not, however, prejudge the epidemiological situation after 2002 whose evolution will also depend on the effectiveness of the provisions made before that date by OCP, then after 2002, by the Regional Office for Africa of the World Health Organization which is currently setting up a sub-regional multidisease surveillance centre.

Growth and destruction are central components of the neuronal injury response. Injured axons that are capable of repair, including axons in the mammalian peripheral nervous system and in many invertebrate animals, often regenerate and degenerate on either side of the injury. Here we show that TIR-1/dSarm/SARM1, a key regulator of axon degeneration, also inhibits regeneration of injured motor axons. The increased regeneration in tir-1 mutants is not a secondary consequence of its effects on degeneration, nor is it determined by the NADase activity of TIR-1. Rather, we found that TIR-1 functions cell-autonomously to regulate each of the seemingly opposite processes through distinct interactions with two MAP kinase pathways. On one side of the injury, TIR-1 inhibits axon regeneration by activating the NSY-1/ASK1 MAPK signaling cascade, while on the other side of the injury, TIR-1 simultaneously promotes axon degeneration by interacting with the DLK-1 mitogen-activated protein kinase (MAPK) signaling cascade. In parallel, we found that the ability to cell-intrinsically inhibit axon regeneration is conserved in human SARM1. Our finding that TIR-1/SARM1 regulates axon regeneration provides critical insight into how axons coordinate a multidimensional response to injury, consequently informing approaches to manipulate the response toward repair., Competing Interests: VC, LO, BP, EN, AB No competing interests declared, (© 2023, Czech, O'Connor et al.)

Phytophthora nicotianae and Ralstonia solanacearum are two of the most important pathogens affecting tobacco worldwide. Greater insight regarding genetic systems controlling resistance to these two soilborne pathogens, as well as identification of DNA markers associated with genomic regions controlling this resistance, could aid in variety development. An evaluation of 50 historical tobacco lines revealed a high positive correlation between resistances to the two pathogens, preliminarily suggesting that some genomic regions may confer resistance to both pathogens. A quantitative trait loci (QTL) mapping experiment designed to investigate the genetic control of soilborne disease resistance of highly resistant 'K346' tobacco identified four QTL significantly associated with resistance to P. nicotianae (explaining 60.0% of the observed phenotypic variation) and three QTL to be associated with R. solanacearum resistance (explaining 50.3% of the observed variation). The two QTL with the largest effect on Phytophthora resistance were also found to be the QTL with the greatest effects on resistance to Ralstonia. This finding partially explains previously observed associations between resistances to these two pathogens among U.S. current cultivars and within breeding populations. Further study is needed to determine whether these relationships are due to the same genes (i.e., pleiotropy) or favorable coupling-phase linkages that have been established over time.

In the tobacco plant, nicotine N-demethylase enzymes (NND) belonging to the cytochrome P450 family catalyse the conversion of nicotine to nornicotine, the precursor of the carcinogenic tobacco-specific N-nitrosamine, N-nitrosonornicotine. To date three demethylase genes, namely CYP82E4, CYP82E5 and CYP82E10, have been shown to be involved in this process, while the related CYP82E2 and CYP82E3 genes are not functional. We have identified a further gene named CYP82E21 encoding a putative nicotine N-demethylase closely related to the CYP82E genes. The CYP82E21 gene was found in all Nicotiana tabacum cultivars analysed and originates from the tobacco ancestor Nicotiana tomentosiformis. We show that, in contrast to all other previously characterized NND genes, CYP82E21 is not expressed in green or senescent leaves, but in flowers, more specifically in ovaries. The nicotine N-demethylase activity of CYP82E21 was confirmed by ectopic expression of the coding sequence in a tobacco line lacking functional CYP82E4, CYP82E5 and CYP82E10 genes, resulting in an eightfold increase of nicotine demethylation compared to the control plants. Furthermore, nornicotine formation can be reduced in ovaries by introducing a CYP82E21-specific RNAi construct. Together, our results demonstrate that the CYP82E21 gene encodes a functional ovary-specific nicotine N-demethylase., (Copyright © 2016 Philip Morris Products S.A. Published by Elsevier Ltd.. All rights reserved.)

Background: This clinical study evaluated the effect of a suctioning maneuver on aspiration past the cuff during mechanical ventilation., Methods: Patients intubated for less than 48 hours with a PVC-cuffed tracheal tube, under mechanical ventilation with a PEEP ≥5 cm H2O and under continuous sedation, were included in the study. At baseline the cuff pressure was set at 30 cm H2O. Then 0.5ml of blue dye diluted with 3 ml of saline was instilled into the subglottic space just above the cuff. Tracheal suctioning was performed using a 16-French suction catheter with a suction pressure of - 400 mbar. A fiberoptic bronchoscopy was performed before and after the suctioning maneuver, looking for the presence of blue dye in the folds within the cuff wall or in the trachea under the cuff. The sealing of the cuff was defined by the absence of leakage of blue dye either in the cuff wall or in the trachea under the cuff., Results: Twenty-five patients were included. The size of the tracheal tube was 7-mm ID for 5 patients, 7.5-mm ID for 16 patients, and 8-mm ID for four patients. Blue dye was never seen in the trachea under the cuff before suctioning and only in one patient (4%) after the suctioning maneuver. Blue dye was observed in the folds within the cuff wall in 6 of 25 patients before suctioning and 11 of 25 after (p = 0.063). Overall, the incidence of sealing of the cuff was 76% before suctioning and 56% after (p = 0.073)., Conclusions: In patients intubated with a PVC-cuffed tracheal tube and under mechanical ventilation with PEEP ≥5 cm H2O and a cuff pressure set at 30 cm H2O, a single tracheal suctioning maneuver did not increase the risk of aspiration in the trachea under the cuff., Trial Registration: ClinicalTrials.gov, number NCT01170156.

Patient dosimetry related to two bone densitometer units from different manufacturers (LUNAR IQ and HOLOGIC 4500A) were evaluated using the parallel beam technique and thermoluminescence from Ca (SO4)/Dy. The radiation dose measured for a phantom of 18 cm in thickness was 0,11 mGy (+/- 0,004) at a maximum current of 3 mA for the LUNAR IQ unit in the high-resolution mode. The radiation dose is 0,28 mGy (+/- 0,011) for the HOLOGIC 4500A unit used at 2,5 mA in the high resolution-mode. These results obtained by thermoluminescence of the Ca (SO4)/Dy are in favor of the LUNAR IQ unit. However, dosimetry must be weighted against image quality.

The western extension area of the Onchocerciasis Control Programme in West Africa (OCP) covers five countries: Guinea, Guinea-Bissau, Mali (western part), Senegal and Sierra Leone. From 1986 to 1990, national teams employed by the respective governments have been regularly collecting entomological data on the vectors of onchocerciasis in these countries. As in the initial programme area of the OCP, the entomological surveillance network was composed of entomological sectors and subsectors (the latter are called "operational bases" in the western extension). In 1990, 308 staff in 47 capture teams were employed for the entomological surveillance activities in seven sectors and twenty-five operational bases. They included a national coordinator as head of the teams for each country, a wide range of technicians, and administrative support staff to assist the national coordinator in the overall management of available resources. The national teams worked under the technical responsibility and supervision of WHO/OCP but with no employee/employer relationship between them and WHO, since they were employed and their salaries were paid by their governments. The OCP, however, paid additional lump sum allowances to each worker, as well as daily subsistence allowances when away from their duty station. Vehicles, entomological equipment, office supplies and furniture, fuel and lubricants were provided by WHO/OCP. Despite the difficulties encountered in the field, which were often great, and their lower salaries (compared with colleagues paid by WHO/OCP), the technical workers in the national teams performed well by OCP standards, with results as satisfactory as those obtained by the WHO/OCP teams in the rest of the programme area. The main reasons for the efficiency and dynamism of the national entomological teams are described. The future of these teams after OCP has ceased its activities is also discussed.

Vertebrobasilar insufficiency is a well-known syndrome, but no corresponding hemodynamic deficit has yet been established. We propose to define nuclear hemodynamic vertebrobasilar insufficiency on the basis of an oligemia lower than 35 mL/100 g per minute in the brain stem-cerebellar region with use of the xenon Xe 133 inhalation method. Fifteen patients fulfilling this criterion underwent four-vessel angiography, computed tomography, and a standardized neurologic examination. An acetazolamide test showed poor reactivity in more than half of the patients, sometimes specifically in the vertebrobasilar area. With use of single-photon emission computed tomography and intravenous technetium Tc 99m-labeled hexamethylpropyleneamineoxime in two cases, the considerable decrease of regional cerebral blood flow in the brain stem-cerebellar region was confirmed. An excellent correlation was observed between the existence of nuclear hemodynamic vertebrobasilar insufficiency and angiographically proved arterial occlusions. The dominant nuclear oligemic zone was regularly on the side of the anatomic arterial chief lesion. Clinical manifestations included rare transient ischemic attacks (in one of 15 patients), intermittent basilar symptoms (in 15 of 15 patients), and a subacute vertebrobasilar "threatening" syndrome. Thus, imaging of a nuclear hemodynamic vertebrobasilar deficit provides an objective basis to the diagnosis of vertebrobasilar insufficiency and useful objective data for revascularization surgery.

The study of cerebral blood flow (DSC) in 29 patients with intracranial aneurysm is interesting to diagnose cerebral ischemia without clinical and radiological effect. A test with nimodipine sensitize this exam, confirm the efficacy of this drug in located ischemias. But may reveal a decrease of cerebral blood flow after nimodipine: it is probably an interesting therapeutic test.

More than 400 patients who had undergone a cerebrovascular attack or a transitory ischemic attack had bilateral measurements of regional C.B.F. by the 133 Xe inhalation technique and a gamma-camera. Inhalation of the air-Xe mixture in the closed spirometric circuit takes 1.5 mn at a concentration of 1 to 2 mCi/1. A very high resolution collimator allows a maximal counting rate of 300 000 i.p.m per hemisphere. At the opening of the circuit, the cerebral curves are analysed by the initial slope index (ISI) method, that index being obtained by deconvolution of the first 2.5 minutes of wash out. With this method, normal values are: 44,5 +/- 5ml/mn/100g. After calculation of hemispheric and regional ISI, we evaluate a regional partition coefficient (for total hemisphére) between tissue and blood with this formula: Formula: [See Text], being the activities counted at time t respectively in the area and on the hemisphere. Koh and Kor referring to ISI in total hemisphere (H) and area (r) C (a): arterial concentration A regional blood flow is obtained by Fr = 100 lambda rKor in a maximum of 16 different areas (with lambda n = 1ml/g) With our data processing system we get a functional image of r CBF which visualizes values of the (lambda r. Kor). In order to avoid statistical problems due to separate calculations of lambda r and Kor in very small areas we use a very simple kind of a functional image: subtraction of regional cerebral activity between time 0.5 and 1.5 mn and at 1.5 and 2.5 mn of wash out. We show that this image is correct display of regional inequalities of lambda rKor. In 48 cases of complete stroke comparison of the ISI index Kor and the ISI index Kor and the lambda r Kor referring to the area of maximal ischemia appearing on the functional image showed perfect correlation between the lambda rKor and the functional image; and only in 80% cases with the unique value of Kor. Those discrepancies between Kor and lambda rKor are related to necrosis and late revascularisation in cerebro vascular attacks.

First the authors make short comments on the two Simuliidae species complexes vectors of African human onchocerciasis (S. damnosum s.l. and S. neavei), as well as on the reasons for renewed interest in the control of those vectors; then they review the various possible methods of control (ecological, biological, genetical and chemical methods) and they finally detail the methodology of anti-S. damnosum chemical larviciding which is the only kind or large scale control presently used against onchocerciasis vectors. The experiences and results of the previous campaigns resulted in the large Onchocerciasis Control Programme in Volta River Basin (O.C.P.) which now appears as a model for present and future control measures against S. damnosum. This Programme is briefly described, together with its results, problems (reinvasion) and orientations. As a conclusion, the excellent level of control of the vectors and onchocerciasis transmission which is obtained is emphasized and it is expected that in the future new large scale campaigns using O.C.P. experience may be initiated.

Hemispheric and regional variations of cerebral blood flow (CBF) were studied with the Xenon inhalation technique on 19 patients suffering from cerebral infarcts before and at the end of a 10 mg 'alpha-blocking' Nicergoline perfusion. CBF dynamic images and calculations were performed with a gamma computerized camera. No significant hemispheric CBF modification has been noted after Nicergoline perfusion (30.2 +/- 4.5 ml/min/100 g before perfusion and 31 +/- 5.6 ml/min/100 g at the end of perfusion) but, at the end of perfusion, we noticed a CBF increase on the more ischemic areas (25.7 +/- 5.6 ml/min/100 g before and 29.9 +/- 6.8 ml/min/100 g after). This variation depends on the patients (from +67% to -22%). The more ischemic areas are those with the more important CBF increase. This 'inverse steel effect' is comparable to the effect described by other authors for Vincamine or Piracetam.

Accidental irradiation of an early and unknown pregnancy during abdomino-pelvic computed tomography has not yet been reported, but this situation will certainly occur as the indications for this type of investigation are extended. Assessment of foetal risk depends essentially, as in ordinary radiology, upon the X-ray dose received by the foetus. Only a few studies have been devoted to determination of the "gonad dose" received during an abdomino-pelvic scan. In ten patients undergoing abdomino-pelvic scan with a mean of 22.1 +/- 4.7 exposures per patient, the authors used a small thermoluminescent dose-meter placed in the uterus or endocervix to measure the gonad dose received. The dose delivered to the uterus was 1.67 cGy +/- 1.14 per patient, i.e. approximately the same as for hysterography (1.27 cGy). Thus any abdomino-pelvic scan before twelve weeks should be viewed as an indication for therapeutic abortion, whilst after twelve weeks the amount of radiation received does not in itself represent an indication for abortion.