Widespread distribution and a new recombinant species of Brazilian virus associated with cotton blue disease.

BACKGROUND: Cotton blue disease (CBD), an important global cotton crop pathology responsible for major economic losses, is prevalent in the major cotton-producing states of Brazil. Typical CBD symptoms include stunting due to internodal shortening, leaf rolling, intense green foliage, and yellowing veins. Atypical CBD symptoms, including reddish and withered leaves, were also observed in Brazilian cotton fields in 2007. Recently, a Polerovirus named Cotton leafroll dwarf virus (CLRDV) was shown to be associated with CBD. RESULTS: To understand the distribution and genetic diversity of CLRDV in Brazil, we analyzed 23 CBD-symptomatic plants from susceptible cotton varieties originating from five of the six most important cotton-growing states, from 2004-2007. Here, we report on CLRDV diversity in plants with typical or atypical CBD symptoms by comparing viral coat protein, RNA polymerase (RdRp), and intergenic region genomic sequences. CONCLUSION: The virus had a widespread distribution with a low genetic diversity; however, three divergent isolates were associated with atypical CBD symptoms. These divergent isolates had a CLRDV-related coat protein but a distinct RdRp sequence, and probably arose from recombination events. Based on the taxonomic rules for the family Luteoviridae, we propose that these three isolates represent isolates of a new species in the genus Polerovirus.

End-systolic left ventricular pressure-dimension shift during acute relief of volume overload in the conscious dog.

To test whether left ventricular (LV) end-systolic dimensions are determined only by end-systolic pressure for a given inotropic state, 7 conscious dogs were studied during abrupt closure of a fistula created between the left subclavian artery and the left atrial appendage. The dogs were instrumented with an LV pressure micromanometer and ultrasonic crystals measuring LV major- and minor-axis diameters and ventricular wall thickness. During beta-blockade treatment and for the same end-systolic pressure, closure of the fistula produced a 40% decrease in cardiac output; end-diastolic diameter decreased by 1.5 mm and end-systolic diameter decreased by 0.9 mm. Calculated end-systolic volume was similarly decreased by 1.3 ml for a decrease of 2.9 ml of end-diastolic volume. Thus, large end-diastolic dimensional variations associated with peripheral resistance decrease significantly modify the end-systolic pressure-diameter (and volume) relations in the conscious animal. It is suggested that indexes obtained from these relations should not be used in patients when systolic pressure variations are associated with large stroke volume variations.

The importance of IL-6 protein expression in primary human renal cell carcinoma: an immunohistochemical study.

AIMS: Interleukin 6 (IL-6) is produced by some renal carcinoma cell lines in vitro. This might be biologically important because IL-6 is a cytokine of particular interest, owing to its involvement in the growth of renal cell carcinoma. In this study, the expression of IL-6 protein in tissue samples from primary renal cell carcinoma was analysed, and then its clinical importance was examined. METHODS: The distribution of IL-6 in renal cell carcinoma was examined by means of an immunohistochemical method in 47 untreated primary renal cell carcinoma samples. The search for a significant difference between histological patterns, Furhman's grading system, TNM classification, and IL-6 protein expression was carried out. RESULTS: Immunohistochemistry demonstrated that IL-6 is expressed in 70% of primary tumours. There was no significant difference in the tumour size and grade between renal cell carcinomas with or without IL-6 expression. However, a relatively large number of high grade tumours expressed IL-6. CONCLUSION: The importance of IL-6 expression with regard to tumour size/local growth is questionable because IL-6 has been correlated with the development of metastatic disease. These data suggest that the production of IL-6 could exert a growth inhibitory effect on primary renal cell carcinoma.

Field trials to control schistosome intermediate hosts by the plant molluscicide Ambrosia maritima L. in the Senegal River Basin.

Several field experiments were carried out in Senegal to evaluate the molluscicidal activity of Ambrosia maritima L. Applications of 400 mg L-1 of dry leaves of the plant in creeks of the Lampsar river did result in a reduction of Bulinus spp of 54-56% 2 weeks after treatment. Treatment of a closed irrigation canal caused a reduction of the density of Biomphalaria pfeifferi up to 77% 2 weeks after the application of 150 mg L-1 and 300 mg L-1. In both trials, however, a quick increase in the snail density was observed after treatment. It is concluded that the large amounts of crude plant material required to achieve snail reductions of less than 80% compromise the use of A. maritima in schistosomiasis control programmes.

Ambrosia maritima: effects on molluscs and non-target organisms.

The actual knowledge about Ambrosia maritima is reviewed with emphasis on recent developments in the fields of plant morphology and taxonomy, the molluscicidal principles--the sesquiterpene lactones--present in the plant and the effects on snails and on non-target organisms. The use of the plant in traditional medicine is also discussed. Areas where more research is needed are outlined.

[Color-Doppler study of the velocity profile of the left ventricular outflow tract in normal subjects and in patients with valvular aortic stenosis]. / Etude du profil de vitesse de la chambre de chasse du ventricule gauche des patients normaux et atteints de rétrécissement orificiel aortique. Etude Doppler couleur.

A better understanding of the velocity profiles in the cardiac chambers and great vessels should allow more accurate estimation of cardiac output and valve surface area by Doppler echocardiography. The velocity profile in the left ventricular outflow tract was studied by Colour Doppler in 12 patients with pure valvular aortic stenosis with normal left ventricular function and compared with a control population of 12 normal subjects. The selected recordings were digitised and stocked on a laser optic disc. Measurement of the angle of incidence of the line of colour aliasing with respect to the interventricular septum was performed manually on a colour video display unit. A program of digitised image processing allowed the tracing of the axes of reference defining the angle of incidence measured at peak systole. The average angle of incidence was 40.7 +/- 5.6 degrees in the control population and 56.8 +/- 6.8 degrees in aortic stenosis; therefore, in this condition, the angle was significantly flatter (less acute) (p less than 0.001). The correlation between the angle of incidence and the transvalvular pressure gradient was poor (r = 0.24). These results suggest that: real time ambulatory analysis of isovelocity profiles in the left ventricular outflow tract is possible by using the phenomenon of colour aliasing: the presence of an obstacle to left ventricular ejection tends to flatten the velocity profile, justifying the use of the continuity equation in patients with calcific aortic stenosis but questioning its systematic use in control populations of normal subjects used as a reference.

[Myxoma of the right ventricle. Apropos of 2 cases]. / Myxomes du ventricule droit. A propos de 2 observations.

Two cases of primary cardiac tumour are reported. The first was that of a 16 year old girl investigated after the detection of a systolic murmur on routine examination. The clinical signs suggested a diagnosis of pulmonary stenosis. The second case was that of a 36 year old man admitted to hospital for right ventricular failure. Echocardiography revealed right ventricular tumours in both cases and also indicated their size, form, mobility and site of implantation. The outcome of the first case, a fibromyxoma, was favourable with no detectable recurrence after one year. In the second case, the patient unfortunately died of cardiogenic shock in the immediate preoperative period. These two cases emphasise the value of echocardiography in the diagnosis of isolated right ventricular tumours, especially considering the difficulty of clinical diagnosis and the risks of angiocardiography.

[Factors influencing survival after surgery of pure non-ischemic mitral insufficiency]. / Facteurs influençant la survie après chirurgie de l'insuffisance mitrale pure non ischémique.

Uni and multifactorial (Cox) statistical analysis of the results of surgery in a series of 247 patients operated between 1969 and 1988 for pure, non-ischaemic mitral regurgitation was undertaken to determine the factors influencing operative and late mortality. All but 3 cases were adults, average age 51 years, and very symptomatic (75 per cent Class III et IV of NYHA Classification). Dystrophic or degenerative lesions were responsible for 53 per cent of cases of regurgitation whilst rheumatic valvular disease was only observed in 30 per cent of cases. Mitral valve replacement was performed in 137 patients (96 mechanical and 41 bioprostheses) and conservative surgery was possible in 110 cases. There were 12 operative deaths (4.9%); the operative risk increased with age and with the practice of valve replacement. Eleven of the 235 survivors (4.7%) were lost to follow-up. During the follow-up period (average 58 months) there were 37 late deaths of which nearly a half were due to left ventricular dysfunction. Multifactorial analysis identified cardiothoracic ratio and atrial fibrillation as predictive factors of late mortality whilst left ventricular ejection fraction and the type of surgery were related to the development of left ventricular dysfunction. The postoperative left ventricular ejection fraction was significantly lower after valve replacement than after valvuloplasty (11 +/- 13% vs 3 +/- 13%; p less than 0.01). These results are therefore in favour of early correction of severe mitral regurgitation by conservative surgery whenever possible.

[Ambrosia maritima L.: study of molluscicidal properties of several generations originating in Egypt and cultivated in Senegal]. / Ambrosia maritima L.: étude des propriétés molluscicides de plusieurs générations d'origine égyptienne et cultivées au Sénégal.

The authors experiment molluscicidal properties of Ambrosia maritima L. from Egypt and cultivated in Senegal. Four generations are tested. Six plants, on eight tested, had same molluscicidal activity as the strain in Egypt.

[Ovine coccidiosis and its treatment under conditions of a livestock market in Senegal]. / La coccidiose ovine et son traitement dans les conditions d'un marché à bétail au Sénégal.

Three lots of 1 to 2 years old sheep are considered: the first is treated by ivermectin subcutaneous (IVOMEC ND), the second by chloroquin per os (NIVAQUINE) and the third is a control one. In the lot treated by chloroquin, 76.92% of sheep show a significant decrease of the EPG, seven days after the treatment. In the lot treated by ivermectin no significant decrease of the EPG is observed after the treatment. However in 50% of these sheep, the number of oocysts in the faeces decreases and their health is improved.

[Study of the effectiveness of morantel tartrate (Exhelm II) in bovine gastrointestinal strongylosis in Ivory Coast]. / Essai d'efficacité du traitement à base de Tartrate de Morantel (Exhelm II) sur la strongylose gastro-intestinale bovine en Côte d'Ivoire.

A study of the seasonal incidence of the strongyles of the bovine digestive tract, under natural climatic conditions (rainfall, humidity and temperature) and the use of Morantel Tartrate (Exhelm II, Pfizer, France) for its control was conducted, in the North of the Ivory Coast during 1976-1977. Young calves belonging to the local breeds Baoulé, N'Dama, and cross bred Zebus-taurins employed for this study were located in the East, West, North and Centre of the Korhogo area. On the basis of the results obtained it could be concluded that: the infestation rate calculated on the basis of egg output, increases during the rainy season, between April and October and decreases during the dry season namely between November and March/April; the animals treated twice or three times with Exhelm II expelled considerably less E.P.G., in comparison to that of the control group. It is suggested that this drug may be used at the dosage rate of 7,5 mg per kg live body weight under field condition at least twice in a year, at the beginning and at the end of the rainy season. A third treatment using this same anthelmintic during the rainy season does not seem to be more profitable than two treatments. As such this third treatment should not however be considered as being essential. N'Dama and Baoule of that region have mixt infection of strongyles comprising of Trichchostrongylus 38%, Oesophastomum 30%, Cooperia 17%, Bunostomum 16%, Haemonchus 15%, Hematodirus 2% and Ostertagia 0,2%.

Effect of self-assembled monolayers on charge injection and transport in poly(3-hexylthiophene)-based field-effect transistors at different channel length scales.

Charge injection and transport in bottom-contact regioregular-poly(3-hexylthiophene) (rr-P3HT) based field-effect transistors (FETs), wherein the Au source and drain contacts are modified by self-assembled monolayers (SAMs), is reported at different channel length scales. Ultraviolet photoelectron spectroscopy is used to measure the change in metal work function upon treatment with four SAMs consisting of thiol-adsorbates of different chemical composition. Treatment of FETs with electron-poor (electron-rich) SAMs resulted in an increase (decrease) in contact metal work function because of the electron-withdrawing (-donating) tendency of the polar molecules. The change in metal work function affects charge injection and is reflected in the form of the modulation of the contact resistance, R(C). For example, R(C) decreased to 0.18 MΩ in the case of the (electron-poor) 3,5-bis-trifluoromethylbenzenethiol treated contacts from the value of 0.61 MΩ measured in the case of clean Au-contacts, whereas it increased to 0.97 MΩ in the case of the (electron-rich) 3-thiomethylthiophene treated contacts. Field-effect mobility values are observed to be affected in short-channel devices (<20 µm) but not in long-channel devices. This channel-length-dependent behavior of mobility is attributed to grain-boundary limited charge transport at longer channel lengths in these devices.

Regional ventricular segmental dynamics in normal conscious dogs.

Left ventricular (LV) subendocardial segmental behavior was analyzed during the whole cardiac cycle for different loading and inotropic conditions in six conscious dogs that were instrumented with ultrasonic crystals in the basal (B) and apical (A) LV regions, a LV micromanometer, and an aortic cuff occluder. There were large variations of A and B segmental behavior during isovolumic contraction and relaxation. In contrast, a linear relationship between A and B was observed during ejection but segmental shortening was larger during control in A than in B, whether it was expressed as a percentage of systolic shortening (34.6 +/- 1.1 and 25.0 +/- 1.2%, respectively; P less than 0.005), or whether segments were normalized for passive resting length. This linear relationship during ejection with a slope of 1.49 was not significantly modified by alterations of loading conditions or inotropic state. The larger A than B shortening, independent of the normalization procedure, is attributed to the regional stress distribution in the LV. The absence of regional and cycle invariance particularly during isovolumic phases prevents the inference of ventricular volume from a limited number of dimensions.

[Epidemiology of gastrointestinal helminthiasis in small ruminants in the tree-cropping pasture zone in Senegal]. / Epidémiologie des helminthoses gastro-intestinales des petits ruminants dans la zone sylvo-pastorale au Sénégal.

An epidemiological survey on gastrointestinal helminthiasis in 51 sheep and 51 goats was held in the tree-cropping pasture region in Senegal from October 1990 to September 1991. All the animals examined were infected with at least 1 helminth species. Three trematodes (Fasciola gigantica, Schistosoma bovis, Amphistomatids), 2 cestodes (Moniezia expansa, Cysticercus tenuicollis) and 9 nematodes were identified. The most important parasite in sheep was Haemonchus contortus while Trichostrongylus colubriformis predominated in goats. The worm burden in sheep was significantly higher than in goats (P < 0.001). L4 larvae of H contortus were found in 85-87% of the small ruminants. There was a negative correlation between haematocrit, number of worms and egg per gram of faeces during the rainy season. These results show that the gastrointestinal nematode burden is high during the rainy season. During the dry season (9 months) nutritional problems are aggravated by adult worms and residual larvae.

Outbreak of intestinal schistosomiasis in the Senegal River Basin.

Intestinal schistosomiasis has never been reported in the delta of the Senegal River Basin. A year and a half after the Diama dam became operational, a first case of Schistosoma mansoni infection was detected at Richard-Toll. In 1988 and 1989, 1,935 stool examinations out of a sample of 3,926 were found positive for S. mansoni. The progression of positive stool samples is rapid in all neighbourhoods of Richard-Toll: 1.9% positive examinations in 1988 compared to 71.5% in the last quarter of 1989. One thousand nine hundred and sixty nine Biomphalaria pfeifferi were collected during several malacological surveys carried out from February 1989 to December 1989 at three observation points. An emission of S. mansoni furcocercariae was determined in 44 out of 926 B. pfeifferi (4.75%) examined during this same period. Intestinal schistosomiasis is new in this area and spreading quickly. Rapid intervention measures are required immediately.

Noninvasive monitoring of cardiac output in critically ill patients using transesophageal Doppler.

Measurement of cardiac output using thermodilution technique in mechanically ventilated patients is associated with significant morbidity. The goal of the present study was to assess the validity of cardiac output measurement using transesophageal Doppler in critically ill patients. Forty-six patients from three different intensive care units underwent 136 paired cardiac output measurements using thermodilution (COTH) and transesophageal Doppler (COTED). In addition, simultaneous suprasternal Doppler and indirect calorimetry (Fick principle) were used to measure cardiac output in 26 patients from one center. A good correlation was found between COTH and COTED (r = 0.95), with a small systematic underestimation (bias = 0.24 L/min) using transesophageal Doppler. The limits of agreement between COTH and COTED were +2 L/min and -1.5 L/min. Variations in cardiac output between two consecutive measures using either transesophageal Doppler or thermodilution techniques were similar in direction and magnitude (bias = 0 L/min; limits of agreement = +/-1.7 L/min). Suprasternal Doppler and indirect calorimetry yielded similar correlations and agreements in the subset of patients in whom they were used. These results confirm that transesophageal Doppler can provide a noninvasive, clinically useful estimate of cardiac output and detect hemodynamic changes in mechanically ventilated, critically ill patients.