[Mosquitoes, Distribution and Specific Richness in Eight Countries of Africa: Cape Verde, Mauritania, Senegal, Gambia, Mali, Burkina Faso, Niger and Chad]

Mosquitoes (Diptera, Culicidae) form a family of insects of considerable public health importance. Mention of their presence/absence was tackled in the literature and by specialized websites for eight African countries: Cape Verde, Mauritania, Senegal, Gambia, Mali, Burkina Faso, Niger and Chad. In total, 216 species have been recorded belonging to 13 genera: Anopheles (48 species), Aedeomyia (2), Aedes (62), Coquillettidia (6), Culex (54), Culiseta (1), Eretmapodites (7), Ficalbia (3), Lutzia (1), Mansonia (2), Mimomyia (7), Toxorhynchites (4) and Uranotaenia (19). The presence of these species in the study area is certain except for three species whose presence is doubtful. This specific richness represents 6% of the world's richness. The countries with the highest specific richness are Burkina Faso (162 species), Senegal (143) and Mali (110); the country with the lowest richness is Cape Verde (11). This richness is lower in the north in hyper-arid climate and higher in the south in sub-humid climate. Chad is the least well inventoried country. All species are considered native, with the exception of Ae. (Stegomyia ) albopictus (the Asian tiger mosquito) introduced in 2016 into Mali and possibly Ae. (Ochlerotatus ) caspius into Mauritania and Ae. (Stg. ) aegypti introduced into Nouakchott, Mauritania. This synthesis of the knowledge may be useful for vector control, public health, and future research.

Is disease activity prior to fingolimod initiation predictive of response? Fingolimod as a "common" first line treatment

BACKGROUND

In countries where fingolimod is available as first-line therapy without restrictions, we have an opportunity to observe long-term efficacy profile of this drug in treatment-naive patients according to their initial disease activity.

METHODS

We retrospectively analysed the data of RRMS patients treated with FTY, focusing on 2 groups: 17 highly active patients (HA) defined as follows: ≥2 relapses in the year before treatment initiation and either≥1 Gd-enhancing T1 lesion or a significant increase in T2 lesion load from a baseline MRI; and 37 "not highly active" (NHA). We reviewed treatment efficacy (defined as NEDA-3), reasons for discontinuation and treatment tolerance in both groups.

RESULTS

Mean follow-up duration was 48.2 months, SD 18.4. Fingolimod efficiently reduced relapses (NHA 90.3% reduction, P<0.001, HA 84.9%, P<0.001), and new Gd enhancing lesions (NHA 85.4% reduction, P=0.019, HA 92.3%, P=0.043). The proportion of patients reaching NEDA-3 status was higher in the NHA group (NHA: 80% at 2 years and 66% at 4 years, HA: 58% at 2 years and 38% at 4 years, P=0.042). Fingolimod was discontinued in 20 cases, mainly because of lack of efficacy (n=15).

CONCLUSIONS

FTY is efficient in reducing relapses and new Gd enhancing lesions in both HA and NHA patients although the probability of achieving NEDA-3 over time is higher in early-treated treatment-naive NHA patients.

First-ever treatment in multiple sclerosis

BACKGROUND

The current treated MS population is very different from that of patients in randomized clinical trials.

OBJECTIVES

To study the long-term efficacy and tolerance of fingolimod (FTY) and dimethyl fumarate (DMF), both available as first-line treatment in early-treated treatment-naïve MS patients.

METHODS

Retrospective analysis of 75 patients from our prospective MS registry fulfilling the inclusion criteria: FTY or DMF as first-line treatment, treatment initiation within 36months of disease onset and treatment duration>12months.

RESULTS

Demographics and MRI characteristics at baseline were similar in both groups (FTY 55 patients, DMF 20), but patients on FTY had higher pretreatment clinical activity (P=0.008). Twenty-two percent of patients in the FTY group and 15% in the DMF group had highly active disease. At last follow-up (mean: 44.2, SD: 17.3months), the majority of the patients were still on treatment while 54.5% of FTY and 65% of DMF patients reached NEDA 3 status (P=0.444). Both treatments significantly decreased relapses and occurrence of new T1 Gd-enhancing lesions (P<0.001). The main reason for discontinuation was disease activity without severe side effects on either treatment.

CONCLUSIONS

Our findings support efficacy and tolerance of both drugs in early-treated treatment-naive MS patients, arguing in favour of efficient early immunomodulation in MS patients. Both drugs significantly reduced the incidence of new relapses and Gd-enhancing lesions on treatment with FTY being more frequently prescribed than DMF, especially in patients with evidence of higher clinical disease activity.

Molecular data reveal a cryptic species within the Culex pipiens mosquito complex

The Culex pipiens mosquito complex is a group of evolutionarily closely related species including C. pipiens and Culex quinquefasciatus, both infected by the cytoplasmically inherited Wolbachia symbiont. A Wolbachia-uninfected population of C. pipiens was however described in South Africa and was recently proposed to represent a cryptic species. In this study, we reconsidered the existence of this species by undertaking an extensive screening for the presence of Wolbachia-uninfected C. pipiens specimens and by characterizing their genetic relatedness with known members of the complex. We first report on the presence of Wolbachia-uninfected specimens in several breeding sites. We next confirm that these uninfected specimens unambiguously belong to the C. pipiens complex. Remarkably, all uninfected specimens harbour mitochondrial haplotypes that are either novel or identical to those previously found in South Africa. In all cases, these mitochondrial haplotypes are closely related, but different, to those found in other C. pipiens complex members known to be infected by Wolbachia. Altogether, these results corroborate the presence of a widespread cryptic species within the C. pipiens species complex. The potential role of this cryptic C. pipiens species in the transmission of pathogens remains however to be determined. The designation 'Culex juppi nov. sp.' is proposed for this mosquito species.

Cytochrome P450s from the fall armyworm (Spodoptera frugiperda): responses to plant allelochemicals and pesticides

Spodoptera frugiperda is a polyphagous lepidopteran pest that encounters a wide range of toxic plant metabolites in its diet. The ability of this insect to adapt to its chemical environment might be explained by the action of major detoxification enzymes such as cytochrome P450s (or CYP). Forty-two sequences coding for P450s were identified and most of the transcripts were found to be expressed in the midgut, Malpighian tubules and fat body of S. frugiperda larvae. Relatively few P450s were expressed in the established cell line Sf9. In order to gain information on how these genes respond to different chemical compounds, larvae and Sf9 cells were exposed to plant secondary metabolites (indole, indole-3-carbinol, quercetin, 2-tridecanone and xanthotoxin), insecticides (deltamethrin, fipronil, methoprene, methoxyfenozide) or model inducers (clofibrate and phenobarbital). Several genes were induced by plant chemicals such as P450s from the 6B, 321A and 9A subfamilies. Only a few genes responded to insecticides, belonging principally to the CYP9A family. There was little overlap between the response in vivo measured in the midgut and the response in vitro in Sf9 cells. In addition, regulatory elements were detected in the promoter region of these genes. In conclusion, several P450s were identified that could potentially be involved in the adaptation of S. frugiperda to its chemical environment.

Molecular complexity determines the number of olfactory notes and the pleasantness of smells

One major unresolved problem in olfaction research is to relate the percept to the molecular structure of stimuli. The present study examined this issue and showed for the first time a quantitative structure-odor relationship in which the more structurally complex a monomolecular odorant, the more numerous the olfactory notes it evokes. Low-complexity odorants were also rated as more aversive, reflecting the fact that low molecular complexity may serve as a warning cue for the olfactory system. Taken together, these findings suggest that molecular complexity provides a framework to explain the subjective experience of smells.

Natural vertical transmission of dengue viruses by Aedes aegypti in Bolivia

The natural transmission of dengue virus from an infected female mosquito to its progeny, namely the vertical transmission, was researched in wild caught Aedes aegypti during an important outbreak in the town of Santa Cruz de la Sierra, Bolivia. Mosquitoes were collected at the preimaginal stages (eggs, larvae and pupae) then reared up to adult stage for viral detection using molecular methods. Dengue virus serotypes 1 and 3 were found to be co-circulating with significant higher prevalence in male than in female mosquitoes. Of the 97 pools of Ae. aegypti (n = 635 male and 748 female specimens) screened, 14 pools, collected in February-May in 2007, were found positive for dengue virus infection: five DEN-1 and nine DEN-3. The average true infection rate (TIR) and minimum infection rate (MIR) were respectively 1.08% and 1.01%. These observations suggest that vertical transmission of dengue virus may be detected in vectors at the peak of an outbreak as well as several months before an epidemic occurs in human population.

How to visualize the spider mite silk?

Tetranychus urticae (Acari: Tetranychidae) is a phytophagous mite that forms colonies of several thousand individuals. Like spiders, every individual produces abundant silk strands and is able to construct a common web for the entire colony. Despite the importance of this silk for the biology of this worldwide species, only one previous study suggested how to visualize it. To analyze the web structuration, we developed a simple technique to dye T. urticae'silk on both inert and living substrates. Fluorescent brightener 28 (FB) (Sigma F3543) diluted in different solvents at different concentrations regarding the substrate was used to observe single strands of silk. On glass lenses, a 0.5% dimethyl sulfoxide solution was used and on bean leaves, a 0.1% aqueous solution. A difference of silk deposit was observed depending the substrate: rectilinear threads on glass lenses and more sinuous ones on bean leaves. This visualizing technique will help to carry out future studies about the web architecture and silk used by T. urticae. It might also be useful for the study of other silk-spinning arthropods.

High-resolution, high-sensitivity NMR of nanolitre anisotropic samples by coil spinning

Nuclear magnetic resonance (NMR) can probe the local structure and dynamic properties of liquids and solids, making it one of the most powerful and versatile analytical methods available today. However, its intrinsically low sensitivity precludes NMR analysis of very small samples-as frequently used when studying isotopically labelled biological molecules or advanced materials, or as preferred when conducting high-throughput screening of biological samples or 'lab-on-a-chip' studies. The sensitivity of NMR has been improved by using static micro-coils, alternative detection schemes and pre-polarization approaches. But these strategies cannot be easily used in NMR experiments involving the fast sample spinning essential for obtaining well-resolved spectra from non-liquid samples. Here we demonstrate that inductive coupling allows wireless transmission of radio-frequency pulses and the reception of NMR signals under fast spinning of both detector coil and sample. This enables NMR measurements characterized by an optimal filling factor, very high radio-frequency field amplitudes and enhanced sensitivity that increases with decreasing sample volume. Signals obtained for nanolitre-sized samples of organic powders and biological tissue increase by almost one order of magnitude (or, equivalently, are acquired two orders of magnitude faster), compared to standard NMR measurements. Our approach also offers optimal sensitivity when studying samples that need to be confined inside multiple safety barriers, such as radioactive materials. In principle, the co-rotation of a micrometre-sized detector coil with the sample and the use of inductive coupling (techniques that are at the heart of our method) should enable highly sensitive NMR measurements on any mass-limited sample that requires fast mechanical rotation to obtain well-resolved spectra. The method is easy to implement on a commercial NMR set-up and exhibits improved performance with miniaturization, and we accordingly expect that it will facilitate the development of novel solid-state NMR methodologies and find wide use in high-throughput chemical and biomedical analysis.

Digestibility and metabolic utilisation of dietary energy in adult sows: influence of addition and origin of dietary fibre

According to a 4×4 Latin square design, four adult ovariectomised sows fed at a similar energy level (516 kJ ME/kg body weight (BW)0·75per d) received one of four diets successively: a control low-dietary-fibre (DF) diet (diet C, 100 g total DF/kg DM) and three fibre-rich diets (200 g total DF/kg DM) that corresponded to a combination of diet C and maize bran (diet MB), wheat bran (diet WB), or sugar-beet pulp (diet SBP). Sows were adapted to the diet for 12 d before an 8 d measurement period. Digestibility of energy and nutrients in the diets, and total heat production (HP) and its components (fasting HP, activity HP and thermic effect of feeding (TEF), were measured. The TEF was partitioned between a short-term component (TEFst) and a long-term component (TEFlt). Total tract digestibility of nutrients and energy was greater for diet C; among the three other diets, the digestibility coefficients were higher for diet SBP than for diets MB and WB. Energy losses from CH4were linearly related to the digestible total DF intake (+1·4 kJ/g). Fasting HP at zero activity averaged 260 kJ/kg BW0·75per d. Activity HP represented 20 % total HP, or 83 kJ/kg BW0·75per d on average. Total TEF and TEFltwere higher (P<0·05) for diet WB than for the other diets. However, total HP (406 kJ/kg BW0·75per d) was not significantly affected by diet characteristics. Our results suggest that metabolic utilisation of dietary energy is little affected by the addition and origin of DF, at least under the conditions of the present study.

Rangewide population genetic structure of the African malaria vector Anopheles funestus

Anopheles funestus is a primary vector of malaria in Africa south of the Sahara. We assessed its rangewide population genetic structure based on samples from 11 countries, using 10 physically mapped microsatellite loci, two per autosome arm and the X (N = 548), and 834 bp of the mitochondrial ND5 gene (N = 470). On the basis of microsatellite allele frequencies, we found three subdivisions: eastern (coastal Tanzania, Malawi, Mozambique and Madagascar), western (Burkina Faso, Mali, Nigeria and western Kenya), and central (Gabon, coastal Angola). A. funestus from the southwest of Uganda had affinities to all three subdivisions. Mitochondrial DNA (mtDNA) corroborated this structure, although mtDNA gene trees showed less resolution. The eastern subdivision had significantly lower diversity, similar to the pattern found in the codistributed malaria vector Anopheles gambiae. This suggests that both species have responded to common geographic and/or climatic constraints. The western division showed signatures of population expansion encompassing Kenya west of the Rift Valley through Burkina Faso and Mali. This pattern also bears similarity to A. gambiae, and may reflect a common response to expanding human populations following the development of agriculture. Due to the presumed recent population expansion, the correlation between genetic and geographic distance was weak. Mitochondrial DNA revealed further cryptic subdivision in A. funestus, not detected in the nuclear genome. Mozambique and Madagascar samples contained two mtDNA lineages, designated clade I and clade II, that were separated by two fixed differences and an average of 2% divergence, which implies that they have evolved independently for approximately 1 million years. Clade I was found in all 11 locations, whereas clade II was sampled only on Madagascar and Mozambique. We suggest that the latter clade may represent mtDNA capture by A. funestus, resulting from historical gene flow either among previously isolated and divergent populations or with a related species.

Molecular characterization of the malaria vector Anopheles gambiae s.s. in Madagascar

Anopheles gambiae s.s. Giles (Diptera: Culicidae), the primary African malaria vector, has been characterized at the subspecies level in Madagascar, where only the molecular form S and haplotype gIA occur. The haplotype gIC proposed by other authors was not observed amongst the 35 mosquito genomes sequenced. These S/gIA characteristics are also found on the Comoros archipelago and in continental Africa.

[Updated inventory of mosquitoes (Dipbra: Culkidae) from the French islets of Europa, Juan-de-Nova and Grande-Glorieuse (Mozambique channel, Indian Ocean)]

The islets of Europa, Juan-de-Nova and Grande-Glorieuse are French territories isolated in the Mozambique Channel (Indian Ocean) which have remained relatively preserved from anthropization all along their history These three islets have been classified entire nature reserves from 1975 and are today inhabited only by a permanent military detachment of about fifteen men even if they occasionally greet technical and scientific staff. Sanitary and environmental issues brought about assessment of the present culicid fauna. The authors propose a synthesis of the culicid knowledge from the islets and make an inventory of new species. The role played by humans in importation of culicids is discussed as well as sanitary consequences of their adaptation to environment

[Anopheles and malaria transmission in Ambohimena, a village in the Occidental fringe of Madagascar Highlands]

The anopheline vectors and malaria transmission were investigated in the Middle West of Madagascar, in the village of Ambohimena (at the altitude of 940 meters) during two years (August 1996 to July 1998). This village is located outside the vector control area, where yearly DDT house spraying campaigns have been conducted between 1993 and 1998. Collection of mosquitoes was mainly based on all night man billing collections (650 man-nights), pyrethrum spray catches (224 bedrooms) and direct collections in outdoor resting places (140 toilets, 61 pigsties, 33 holes, 19 sheds, 79 sisal hedges, 70 cart shelters). Blood fed anophelines allowed analysis of the origin of blood with an ELISA method. Presence of circum-sporozoite protein was assessed with another ELISA method. The total number of collected anophelines was 14,280. Two malaria vectors were identified: Anopheles funestus Giles, 1900 and An. arabiensis Patton, 1902. An. funestus was the most abundant mosquito, especially during the hot rainy season. Two peaks of abundance were observed (in December and April). Endophagic rate (for mosquitoes aggressive for man) of 35.3%, an endophilic rate (for resting mosquitoes) of 78.0% and an anthropophilic rate (for indoor resting mosquitoes) of 64.0% were calculated. The average parity rate was relatively low (61.2%). The Plasmodium falciparum immunological sporozoite rate was 0.20%. An. funestus presented a higher vectorial capacity during the first round of rice cultivation (January) than during the second round (April-May). An. arabiensis was mostly abundant in December and January at the beginning of the rainy season. This species was exophagic (endophagic rate = 27.5%) and zoophilic (anthropophilic rate = 7.8%). The sporozoitic index was determined as zero (number of examined mosquitoes = 871). In this village, An. arabiensis presented only marginal importance for malaria transmission. Malaria transmission occurred from December to April. Annual entomological inoculation rate, only due to An. funestus, was 8.96 during the first year, and 3.17 during the second year. In this area where transmission is moderately stable, we suggest an extension of vector imagocidal control activities up to the western fringes of the Highlands.

[Ecoethology of vectors and transmission of malaria in the lowland rice growing region of Mandritsara, Madagascar ]

To evaluate the determining factors of the malaria transmission in the northwest region of Madagascar, transversal studies were carried out through one year, from March 1997 to April 1998, in two villages located near Mandritsara, at less than 300 meters above sea level. The rice-growing region forms an intermediate zone between the central highlands with epidemic and instable malaria and the coastal zone with endemic and stable malaria. Mosquitoes were collected when landing on humans during the night and by pyrethrum spray catches as regards endophilic mosquitoes. Three vectors were identified: Anopheles arabiensis, An. gambiae and An. funestus. An. arabiensis and An. gambiae were exophagic and zoophilic. An. funestus was endo-exophagic and anthropophilic but this species shows also a zoophilic trophic deviation. In both villages, An. funestus is the main vector of human malaria. Malaria transmission was estimated to be around 50 and 70 infective bites/person/year in each village.

Microarray analysis of cytochrome P450 mediated insecticide resistance in Drosophila

Insecticide resistance in laboratory selected Drosophila strains has been associated with upregulation of a range of different cytochrome P450s, however in recent field isolates of D. melanogaster resistance to DDT and other compounds is conferred by one P450 gene, Cyp6g1. Using microarray analysis of all Drosophila P450 genes, here we show that different P450 genes such as Cyp12d1 and Cyp6a8 can also be selected using DDT in the laboratory. We also show, however, that a homolog of Cyp6g1 is over-expressed in a field resistant strain of D. simulans. In order to determine why Cyp6g1 is so widely selected in the field we examine the pattern of cross-resistance of both resistant strains and transgenic flies over-expressing Cyp6g1 alone. We show that all three DDT selected P450s can confer resistance to the neonicotinoid imidacloprid but that Cyp6a8 confers no cross-resistance to malathion. Transgenic flies over-expressing Cyp6g1 also show cross-resistance to other neonicotinoids such as acetamiprid and nitenpyram. We suggest that the broad level of cross-resistance shown by Cyp6g1 may have facilitated its selection as a resistance gene in natural Drosophila populations.

[Review of genus Coquilletidia (Diptera: Culicidae) in Madagascar and description of the larva of Cq. grandidieri (Blanchard, 1905)]

The genus Coquilletidia includes some of the mosquitoes involved in the transmission of numerous arbovirosis. Adults are locally abundant and very aggressive for men. In Madagascar, thus genus concerns 3 species among which 2 are endemic and had not been described at larval stage this far. The authors describe a single larva of Coquilletidia collected at Ankazobe in the Middle West of Madagascar, at an altitude of 1200 meters. The geographical distribution of Coquilletidia adults collected in various bio-climatic zones in Madagascar, combined with observed morphological characters, permit us to attribute this larva to Cq. grandidieri.

[Anopheles mascarensis of Meillon 1947, a malaria vector in the middle west of Madagascar?]

Anopheles mascarensis has been demonstrated to be a vector of human malaria in the East coast of Madagascar. Here, we present original data obtained from 1996 to 2003 on the distribution, biology and vectorial capacity of An. mascarensis in the Middle-West of Madagascar. This species is consistently exophilic both for its trophic and resting behaviour. This accounts for the absence of clear impact of any indoor insecticide spraying. This species is mainly zoophilic, but can occasionally bite humans, which explains a low sporozoitic index (1/2218 = 0.045%). The densities of human landing mosquitoes are most of the time very low, with the exception of a peak between May and August at the beginning of the dry season. It implies that the vector's efficiency is very low but not insignificant in the Middle-West of Madagascar, a situation opposite to what is observed on the East coast. The vectorial efficiency of An. mascarensis and An. arabiensis would enable to maintain a low malarial endemicity in the Middle-West, even in the complete absence of An. funestus.

[Recent observations on the sensitivity to pyrethroids and DDT of Anopheles arabiensis and Anopheles funestus in the central Highlands of Madagascar; preliminary results on the absence of the kdr mutation in An. arabiensis]

Anopheles arabiensis and Anopheles funestus are the principal vectors of malaria on the central highlands of Madagascar. These two species of mosquito are directly or indirectly the targets of indoor insecticide spread. The survey of the susceptibility of these two vectors to insecticides is essential specifying for the anti-vectorial current directives and for the future programs. This paper describes: --the recent tests of susceptibility and the study of the knock-down effect of four pyrethroids (deltamethrin 0.50%, permethrin 0.250%, alpha-cypermethrin 0.025%, cyfluthrin 0.150%) and DDT 4% on An. arabiensis collected from December 2002 to May 2003 in three villages on the district of Tsiroanomandidy and in Alasora, a rural area near the capital, Antananarivo. --the susceptibility tests of An. funestus realised in Morafeno, against cyfluthrin 0.150%, deltaméthrin 0.050%, lambda-cyhalothrin 0.050% and DDT 4%. --the preliminary study of the kdr gene mutation, which might account for the pyrethrinoid and DDT resistance, of An. arabiensis in Alasora. The data indicate a decrease in the efficiency of alpha-cypermethrin 0.025% (Tkd99 = 21 mn) and of DDT 4% (Tkd99 = 191.5 mn) on An. arabiensis in Analamiranga. Nevertheless, the effectiveness of permethrin 0.250% has been notified. In Soanierana, alpha-cypermethrin 0.025% was effective against An. arabiensis, whilst the ineffectiveness of the DDT 4% (Tkd99 = 116 mn) in Andranonahoatra was observed. In Alasora, a fall in the effectiveness of alpha-cypermethrin 0.025% (Tkd99 = 21 mn) and the resistance to DDT 4% (Tkd99 = 6894 mn) was noted. No kdr mutation was detected on the kd gene of An. arabiensis resistant to the alpha-cypermethrin 0.025% and to DDT 4%, collected in Alasora. An. funestus collected in the district of Miandrivazo is susceptible to pyrethroids and to DDT. To conclude, in the Malagasy Central Highlands, An. arabiensis is ordinary sensitive to pyrethroid and poorly sensitive, or even resistant to DDT (as observed in Antananarivo plain). However, An. funestus remains sensitive to all tested insecticides; this observation is crucial because this anopheles vector is the first target of the campaigns of indoor spraying insecticides.

[Systematics and biology of Anopheles vectors of Plasmodium in Africa, recent data]

Renewed interest in research on Plasmodium vectors in Africa and development of genetic and molecular biology techniques has been spearheaded by the WHO and the PAL+ program of the French research ministry. New findings have led to a better understanding of the systematics and biology of the main vector groups. The purpose of this article is to describe the newest data on the Anopheles gambiae complex and the M and S forms of An. gambiae s.s., on species in the An. funestus group and genetic polymorphism of An. funestus, on the two probable species in the An. moucheti complex, and on An. mascarenesis.

[Insecticide sensitivity in malaria vectors in high altitude Madagascar after five years of vector control]

In 1991, Anopheles gambiae and Anopheles funestus, the main malaria vectors in the Highlands of Madagascar, were reported to be fully susceptible to DDT; nevertheless a slight decrease in the susceptibility levels was recorded when compared with previous assays carried out in 1962. From 1993 to 1997, five cycles of indoor residual spraying have been carried out in the Highlands: a total of 1,482,000 kg of 70% wp DDT have been used for the treatment of houses and animal shelters. From 1996 to 1999, adult mosquito susceptibility tests to DDT and to some pyrethroids (lambdacyalothrine, deltamethrine, permethrine and cyfluthrine) have been carried out on samples collected in 20 areas of the Highlands. Bioassays were carried out following the WHO standard method. All tested populations of An. funestus showed a full susceptibility to DDT. An. gambiae showed a widespread decrease in the susceptibility to DDT, particularly marked in the region of the capital city Antananarivo. Both species were susceptible to pyrethroids.

A single p450 allele associated with insecticide resistance in Drosophila

Insecticide resistance is one of the most widespread genetic changes caused by human activity, but we still understand little about the origins and spread of resistant alleles in global populations of insects. Here, via microarray analysis of all P450s in Drosophila melanogaster, we show that DDT-R, a gene conferring resistance to DDT, is associated with overtranscription of a single cytochrome P450 gene, Cyp6g1. Transgenic analysis of Cyp6g1 shows that overtranscription of this gene alone is both necessary and sufficient for resistance. Resistance and up-regulation in Drosophila populations are associated with a single Cyp6g1 allele that has spread globally. This allele is characterized by the insertion of an Accord transposable element into the 5' end of the Cyp6g1 gene.

Digestibility and metabolic utilisation of dietary energy in adult sows: influence of addition and origin of dietary fibre

According to a 4 x 4 Latin square design, four adult ovariectomised sows fed at a similar energy level (516 kJ ME/kg body weight (BW)0.75 per d) received one of four diets successively: a control low-dietary-fibre (DF) diet (diet C, 100 g total DF/kg DM) and three fibre-rich diets (200g total DF/kg DM) that corresponded to a combination of diet C and maize bran (diet MB), wheat bran (diet WB), or sugar-beet pulp (diet SBP). Sows were adapted to the diet for 12 d before an 8 d measurement period. Digestibility of energy and nutrients in the diets, and total heat production (HP) and its components (fasting HP, activity HP and thermic effect of feeding (TEF), were measured. The TEF was partitioned between a short-term component (TEF(st)) and a long-term component (TEF(lt)). Total tract digestibility of nutrients and energy was greater for diet C; among the three other diets, the digestibility coefficients were higher for diet SBP than for diets MB and WB. Energy losses from CH4 were linearly related to the digestible total DF intake (+1.4kJ/g). Fasting HP at zero activity averaged 260 kJ/kg BW(0.75) per d. Activity HP represented 20% total HP, or 83 kJ/kg BW(0.75) per d on average. Total TEF and TEF(lt) were higher (P<0.05) for diet WB than for the other diets. However, total HP (406kJ/kg BW(0.75 per d) was not significantly affected by diet characteristics. Our results suggest that metabolic utilisation of dietary energy is little affected by the addition and origin of DF, at least under the conditions of the present study.

[The campaign against malaria in central western Madagascar: comparison of lambda-cyhalothrin and DDT house spraying. II--Parasitological and clinical study]

For malaria vector control in Madagascar, 10 WP (lambda-cyhalothrin 10% wettable powder) was compared with DDT 75% WP for house-spraying, from November 1997 to September 1998. This study was implemented at the fringe of the malaria epidemic zone, in villages on western slopes of the central highlands, outside the area covered for the past five years by routine DDT house-spraying (OPID). Four types of treatment were compared in different areas: 1) DDT 2 g ai/m2 and 2) lambda-cyhalothrin 30 mg ai/m2 in previously unsprayed villages, 3) no intervention (control); 4) yearly DDT spraying (OPID fifth cycle). To investigate the malariological impact of spraying, cross-sectional surveys of the village populations were performed in each study area at intervals of two months, before and after spraying. In the newly sprayed areas, from December to June, malaria indices decreased by 62% in the ICON area and 44% in the DDT area, whereas in the unsprayed village malaria increased by 32% during the same season. There was a similar decrease in the number of gametocyte carriers in the newly sprayed areas. Active malaria case detection among febrile individuals was performed fortnightly in each village outside the OPID area. Results showed decreased malaria incidence from February (two months post-spraying) in the sprayed villages, despite the rainy season, whereas in the unsprayed area the decline occurred only after the main transmission season. This study demonstrated that, parasitologically as well as entomologically, house-spraying with residual insecticide (DDT or ICON) was an effective method for controlling malaria on the western fringes of the Madagascar highlands epidemic zone. Both products were effective, but ICON had slightly better impact than DDT, i.e. more reduction of malaria indices and of vector longevity, less irritancy of mosquitoes. For best results in this area of transition between stable and unstable malaria, we recommend earlier annual spraying (as soon as November) and extension of the OPID barrier towards western and northern slopes of the Plateau.

[The campaign against malaria in central western Madagascar: comparison of the efficacy of lambda-cyhalothrin and DDT house spraying. I--Entomological study]

For malaria vector control in Madagascar, the efficacy of lambda-cyhalothrin 10% wettable powder (ICON 10 WP) was compared with DDT 75% WP for house-spraying. This evaluation was conducted from November 1997 to September 1998 in highland villages of Vakinankaratra Region, at the fringe of the malaria epidemic zone, outside the zone covered by routine DDT house-spraying (Opération de pulvérisation intro-domiciliaire de DDT: OPID zone). Treatments were compared by house-spraying in four areas: 1) application of DDT 2g ai/m2 and 2) lambda-cyhalothrin 30 mg ai/m2 in previously unsprayed villages; 3) no intervention (control); 4) OPID 5th cycle of DDT 2g ai/m2. The prevalent vector Anopheles funestus almost disappeared from both the DDT and ICON sprayed areas, whereas in the unsprayed (control) area An. funeslus density went up to 60 females per room in April and there were two seasonal peaks of malaria transmission in January and March (see following paper). In the area sprayed with ICON, the parous rate of An. funestus decreased from 47% pre-spray to 39% six months post-spraying, while the parous rate increased in DDT-sprayed area (from 57% pre-spray to 64% six months post-spray). Bioassays of An. funestus on treated walls, six months post-spray, gave mortality rates of 100% on DDT and 90% on ICON. Conversely, ICON appeared to be more effective than DDT on thatched roofs (66% versus 100%, respectively, six months post-spray). In areas sprayed with DDT or ICON the density of An. arabiensis were little affected. This study demonstrated that, under equivalent conditions, both DDT and lambda-cyhalothrin were effective in reducing malaria transmission on the western fringes of the malaria epidemic zone of the malagasy highlands, with a residual effect lasting at least for six months. Lambda-cyhalothrin appeared to be more effective than DDT in reducing the longevity of malaria vectors. In addition to efficacy, the choice of insecticide for malaria vector control should take into account their acceptability by human populations and their toxicity and persistence in the environment.

Comparative total tract digestibility of dietary energy and nutrients in growing pigs and adult sows

Seventy-seven diets were fed to 61-kg growing pigs at a feeding level close to their ad libitum intake and to nonlactating, nonpregnant sows slightly above their maintenance energy level (2.4 kg/d). The main objectives of this study were to compare the total tract digestibility of dietary energy or nutrients of the 77 diets in growing pigs and adult sows and to analyze the effect of diet chemical composition on total tract digestibility in both groups of pigs. Diets were formulated to represent a range of chemical compositions as large as those found in most practical situations. The DE and ME values and total tract digestible nutrient contents of diets were measured for each group of animals; each diet was measured in four to five animals per group, and collection of urine and feces lasted 10 d. The results were used to establish equations for predicting DE and ME values, total tract digestible nutrient contents, and total tract digestibility coefficients of energy from chemical characteristics for each group of animals. The results show that the total tract digestibility of energy or nutrients was higher (P < 0.01) in adult sows than in growing pigs; the total tract digestibility coefficients of energy, crude protein, ether extract, and NDF averaged 85.2, 85.1, 37.1, and 64.4%, respectively, for sows and 82.1, 80.3, 31.6, and 56.3%, respectively, for growing pigs. The ME/DE ratio was lower (P < 0.01) in sows (94.8%) than in growing pigs (96.5%), as a result of higher urinary energy losses in sows. The difference in DE values (on average, 0.6 MJ/kg of DM) between adult sows and growing pigs was not constant (P < 0.01) but increased with dietary fiber content (3.3, 8.6, and 10.1 kJ for each gram of NDF, ADF, and crude fiber increase in the diet, respectively), which suggests that the origin of the difference between the two physiological stages is mainly due to a higher rate of degradation of dietary fiber in the hindgut of sows. The DE and ME values could be accurately predicted from total tract digestible nutrients or from chemical characteristics for each physiological stage. Equations for predicting urinary energy loss from urinary N are also proposed. From a practical point of view, it is suggested to use two energy values for pig feeds: one applicable to growing-finishing pigs and one to adult sows. Equations for predicting DE in adult sows from energy values obtained in growing pigs are proposed.

The sibling species Drosophila melanogaster and Drosophila simulans differ in the expression profile of glutathione S-transferases

Two major forms of glutathione S-transferase are known in Drosophila melanogaster: GST D and GST 2. In the present paper we report the existence of a third major form of glutathione S-transferase in Drosophila simulans. Induction with phenobarbital revealed a different regulation of GST between these species. Despite the fact that these two species are closely related, there was a difference in the expression profile of the enzyme implicated in the detoxification system, suggesting variations in capacity to suit their environment.

Density and dispersal of the loaiasis vector Chrysops dimidiata in southern Cameroon

By mark-release-recapture experiments, we assessed the density of loaisis vectors, Chrysops dimidiata Wulp plus some Chrysops silacea Austen (Diptera: Tabanidae) and estimated their range of flight in the secondary forest of southern Cameroon. In 1993, the release point was at the centre of the study area and recapture points were at 1,100 m radius. In 1994, releases were on the periphery of the study area and recapture sites were 400-8,000 m from the release points. Results were concordant and showed Chrysops female densities of 785-3,682 flies/ km2. The theoretical flight range was < 6,000 m, with a maximum distance of 4,500 m observed. These results are considered promising for the use of vector control methods against loaiasis.

Afro-tropical anopheline mosquitoes. III. Description of three new species: Anopheles carnevalei sp. nov., An. hervyi sp. nov., and An. dualaensis sp. nov., and resurrection of An. rageaui Mattingly and Adam

Anopheles (Cellia) carnevalei sp. nov. is described as a new species morphologically similar to Anopheles nili. This aggressive human biter was collected in Ivory Coast. Anopheles (Cellia) hervyi sp. nov. was collected in southern Niger and is described as a new species morphologically similar to Anopheles salbaii. Anopheles (Cellia) dualaensis sp. nov. is a new species from Duala in southern Cameroon. The synonymy of Anopheles cavernicolus and Anopheles smithii is confirmed. Based on extensive reexamination of larval and adult morphology, the authors suggest that Anopheles (Cellia) rageaui Mattingly and Adam should no longer be considered as a synonymn of An. smithii.

[The microwave oven for drying thick blood smears. Benefits and limits for microscopic observation of Plasmodium falciparum trophozoites and gametocytes]

The micro-wave oven permits a rapid drying of thick blood smears classically used for parasitological malaria diagnosis. In order to evaluate this type of drying on the microscopic reading, a study was carried out in an hyperendemic area of malaria with 382 asymptomatic volunteers of all ages. Two thick smears were made for each volunteer, one immediately dried with a micro-wave oven for one minute, the second dried in the open air without any intervention. A single microscopist examined all the thick smears. The observation of Plasmodium falciparum trophozoites differed significantly between the two methods, the prevalence was 50% by normal drying versus 41% by the micro-wave oven. The geometric mean of the trophozoite number for positive thick smears was significantly lower with the micro-wave oven. When the parasitological density with normal drying was lower than 200 trophozoites/microliter of blood, 54% of results were wrongly negative with the micro-wave oven. On the other hand, the observation of P. falciparum gametocytes was significantly facilitated after drying with the micro-wave oven; the prevalence was 8% with normal drying versus 12% by micro-wave oven. In conclusion, the use of the micro-wave oven for the drying of thick smears is not recommended for malaria diagnosis although it improves the observation and counting of P. falciparum gametocytes.

Comparison of three sampling methods of man-biting anophelines in order to estimate the malaria transmission in a village of south Cameroon

In order to get an accurate measure of malaria transmission by mean of human bait attraction, three methods of catches for human-bail mosquitoes were compared in a Cameroonian village of high anopheline density. These three methods were 1) the classical human landing catches where the man was in the same time bait and catcher, 2) the single-nets which acted as a trap and 3) the double-nets where the outer net acted as a trap and the inner avoided mosquito bites. The anopheline densities per man with human landings were 1.6 time higher than those obtained with single-nets, these later being 4.7 times higher than those obtained with double-nets. In the three methods, the results were similar for the anophelines species catched and for their respective proportions. The samples of Anopheles nili and An. gambiae had comparative parity rates and sporozoitic indexes. From these results, in order to estimate the malaria transmission it can be envisaged to change the standard human-bait catch for the human-baited single bed-net catch; on the contrary the double-net have to be discarded because of their poor results.

Detection of falciparum malarial forms in naturally infected anophelines in Cameroon using a fluorescent anti-25-kD monoclonal antibody

Anopheles gambiae s.s. and An. funestus were sampled in houses located in a Plasmodium falciparum-holoendemic site in southern Cameroon. The midguts of female mosquitoes in half-gravid or gravid stages of blood digestion were incubated with a fluorescent monoclonal antibody directed against the P. falciparum zygote/ookinete surface protein Pfs25 and examined using a fluorescent light microscope. Malarial forms were detected in 11.6% of the half-gravid mosquitoes and in 0.0% of the gravid ones (P = 0.012). No difference in infections or the occurrence of malarial forms between An. gambiae and An. funestus was observed. Overall, 127 malarial forms were counted and distributed among round forms, retorts, and ookinetes in 77.2%, 9.5%, and 13.4%, respectively. Round forms include macrogametes, activating microgametocytes, and zygotes. The mean number of malarial forms per infected midgut was 2.16 and the maximum number observed was 13. In four anophelines, round forms, retorts, and ookinetes were simultaneously observed. Sporozoite rates were 5.7% for An. gambiae and 3.8% for An. funestus. In the human population, the gametocyte index for P. falciparum was 38% with a mean density of 1.11 gametocytes per microliter of blood. Differences concerning malarial forms in mosquito midguts were observed between houses (range percentage = 4.7--21.3%; mean range of forms per positive anopheline = 1.1--3.1). In each house, relationships existed between infected vectors and the gametocyte reservoir of their inhabitants. The role in transmission of people with very low gametocytemia, approximately one per microliter, as a reservoir of falciparum malaria in highly endemic areas, is emphasized.

[Evaluation of a DEET-based repellent on 3 vectors of malaria in central Africa]

As part of the framework of studies on personal protection against disease-transmitting mosquitoes, a field evaluation was carried out in a forest area of Cameroon on human subjects to assess the efficacy of a common repellent: DEET (a 50% active ingredient formulation). One ml of DEET applied to the legs of resting persons gave an 85% reduction in Anopheles bites during the 5 hours following application. The repellent effect decreased gradually with time. The effect was more than 90% maximum after 3 hours, 50% by about the seventh hour and declined to 0% from the fifteenth hour onwards. No difference was found between the three Anopheles species: Anopheles gambiae ss, An. nili and An. funestus. The longevity and infectivity of Anopheles populations caught on humans with repellent and on untreated controls were similar. Thus the reduction of biting rate can be considered equivalent to the reduction in malaria transmission. The effect of sweating on the loss of the applied repellent was studied. Moderate sweating, corresponding to normal activity, did not reduce the efficacy of the repellent. More profuse sweating did not significantly reduce repellent efficacy. We conclude that the tested formulation of DEET has the same efficacy as commercial formulations already on the market. Protection did not last the whole night, which is the time required for protection against malarial infection. However, good protection levels lasted more than 5 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy of insecticide impregnated bed-nets to control malaria in a rural forested area in southern Cameroon

Due to current spreading of chemoresistant strains of Plasmodium falciparum malaria control must incorporate vector control programmes. Due to well known constraints house sprayings cannot be performed as before. Personal protection can be developed and a large scale use of insecticide treated bed-nets appeared to be very useful to reduce man-vector contact in Asia, South America and West and East Africa. No trial has been done in forest Central Africa where transmission is permanent. We performed such a trial in the southern part of Cameroon (using deltamethrin, at 25 mg/m2) and obtained similar data to those observed in The Gambia, Burkina Faso and Tanzania with a noteworthy reduction of both transmission and high parasitaemia of P. falciparum (respectively 78% and 75%) meaning a drop of malaria morbidity.

Early sporogonic development in local vectors of Plasmodium falciparum in rural Cameroon

In ongoing studies on experimental transmission of Plasmodium falciparum in the city of Yaounde gametocyte carriers are daily being identified among dispensary patients with malaria-like complaints. This species comprises 93% of all parasitemias and because of the selection criteria most patients have it as a recent infection. 17% of all P. falciparum-positives carry detectable gametocytes with little difference between youngsters and adults. Blood of adult carriers is taken and infection of Anopheles gambiae mosquitoes is attempted by membrane feeding; the establishment of infection is judged by the presence of oocysts.

[Comparison of catches by landings on humans and by CDC light traps for sampling of mosquitoes and evaluation of malaria transmission in South Cameroon]

The classical method to estimate the malaria transmission in an endemic area is based on the number and infectivity of human landing mosquitoes. To compare this method with CDC Miniature Light Trap a study was carried out in a forested area of South Cameroon. Light-trap and servant were placed in six different houses of the same village from 08 p.m. to 06 a.m. In average the human landing caught 29.9 anopheline females per night, while light-trap 52.4. The ratio of light-trap on human landing was 1.75 for Anopheles genus. This ratio varied with the species: 1.88 for An. nili and 0.54 for An. gambiae s.s. Light-trap showed disadvantages, especially the lack of steadiness and the fact that only 49.6% (n = 238) of potential vectors of malaria were in good standing for dissection of salivary glands. The authors concluded that human landing remained the most efficient method of catching for the estimation of human malaria transmission in the forested area of Africa. Nevertheless, the lower cost of light-trap is an important advantage.

Anthropophilic mosquitoes and malaria transmission at Edea, Cameroon

An entomological study was carried out during 1990 in the town of Edea in the south of Cameroon to study anthropophilic mosquitoes with special reference to malaria transmission. Man-biting mosquitoes were caught regularly during one night each month in two different districts: Bilalang which is a well planned suburb with 160 houses on a hill-top, provided with a piped water supply; and Pongo which is a densely urbanised suburb in a valley. From 188 man-nights 1030 mosquitoes were collected, comprising 700 Culex quinquefasciatus (68%), 262 Anopheles gambiae (25%) and others species (7%) belonging to the genus Anopheles, Mansonia, Culex and Aedes. The estimated annual biting rates of mosquitoes were 811 bites per man in Bilalang and 2,866 in Pongo. The estimated yearly malaria inoculation rates were 3.8 and 30.2 infective bites per man in Bilalang and Pongo, respectively. In different parts of Pongo district much variation existed; extreme values of the estimated yearly inoculation rate were zero and 86.3 in two houses 200 m apart, located on the top of a hill and in the bottom of a valley, respectively. This study is one of the first conducted on malaria transmission in a moderate sized African town; it shows that the mosquito populations are typically urban and differ greatly from rural ones.

[Feasibility of mosquito control using insecticide-impregnated bednets in rural areas of Cameroon]

The feasibility of using impregnated bednets in a malaria control strategy has been evaluated in a rural area of Cameroon. The benefit is well perceived by the population in terms of protection against nuisance but not in terms of prevention of the disease. The correct use of bednets is, however, unsatisfactory. The material should be adapted to the various sleeping accommodations, and efforts for education and information directed towards the potential users should be intensified.

[Mass and geometry of the left ventricle. Methods of angiographic determination]

Hypertrophy is a myocardial adaptation to pathological conditions of overload and leads to a reduction of cardiac afterload. Angiocardiography (the so-called reference method) allows calculation of mass and volume after opacification of the left ventricle in two orthogonal planes, based on different mathematical models: the area-length method: the left ventricle is assumed to be ellipsoid. The short axis diameter and the volume are calculated from measurements of the area of the left ventricle in the long axis; Simpson's method: the ventricle is divided into sections along its long axis. The diameters of the sections are measured in each incidence. Left ventricular volume is calculated from the area of each section and the distance between two sections; myocardial mass: calculation of the myocardial mass requires measurement of the volumes of the left ventricle with the diameters increased by twice the wall thickness. The accuracy of these measurements depends on several factors: geometrical: true parallelism between the long axis of the ventricle and the planes of projection; influence of the contrast medium in the volume and contraction; this is negligible in the first three systoles; detection of the ventricular contours: this may be manual or automatic and requiring techniques of image digitalization. Therefore, the calculation of ventricular mass is directly related to volume determination, and hypertrophy can only really be quantified by mass/volume or wall thickness/diameter ratios.

[Enoximone, vasodilator and/or inotropic agent in congestive cardiac insufficiency? Hemodynamic and ventriculographic study of 20 cases]

The aim of this study was to document the effects of enoximone in congestive cardiac failure. The haemodynamic data (aortic pressure, pulmonary pressures, left ventricular pressure, cardiac output, isovolumic contractility index: Vmax) and left ventricular kinetics of 20 patients with dilated cardiomyopathy (11 ischemic and 9 idiopathic in Stages III or IV of the NYHA Classification before recompensation) were recorded under basal conditions, after 30 minutes infusion of dobutamine (10 micrograms/kg/mn) and after 3 hours infusion of enoximone (total dose: 3.6 mg/kg). The two drugs had an equivalent inotropic effect: ejection fraction + 4 +/- 22% with dobutamine and + 16 +/- 39% with enoximone; Vmax increased from 1.53 +/- 0.5 c/sec to 2.49 +/- 0.8 c/sec with dobutamine and to 1.82 +/- 0.5 c/sec with enoximone. Enoximone induced a greater degree of vasodilation (systemic resistances - 14 +/- 21% with dobutamine and - 21 +/- 27% with enoximone) and a more pronounced fall in ventricular filling pressures (- 35 +/- 42% with dobutamine and - 58 +/- 24% with enoximone). Enoximone was less effective than dobutamine in increasing cardiac output (+ 46 +/- 42% with dobutamine and 16 +/- 33% with enoximone) and stroke volume (+ 23 +/- 47% with dobutamine and + 2 +/- 41% with enoximone). This difference in efficacy may be explained by the major reduction in ventricular preload which enoximone induced after that observed with dobutamine. "Responders" (12 patients) had basal cardiac outputs of less than 2.3 l/mn/m2; the peripheral vasodilatation caused by enoximone was greater. Finally, the reduction in left ventricular end diastolic pressure and the increase in Vmax were significantly less in the 11 patients with ischemic cardiomyopathy.(ABSTRACT TRUNCATED AT 250 WORDS)

[Campaign against the vectors of onchocerciasis in the surroundings of a refugee camp located in a savanna zone of Cameroon]

In view of the risks of onchocerciasis facing Chadian refugees who have settled in a camp in a savanna hyperendemic area of northern Cameroon, the authors concluded that a vector control directed against the black fly larvae located on small seasonal tributaries of the main water course of this area should be carried out during the four to five months of the rainy season, i.e., during the whole period of transmission of this disease. The operations were undertaken during two consecutive rainy seasons. The first year consisted in developing ground-based control techniques and evaluating the larvicidal efficacy at the larval level. The second year was, particularly, devoted to the study of the impact of the vector control on the biting rate and on the transmission of onchocerciasis. Every week, three of the tributaries close to the camp were treated with an Emulsifiable Concentrate of temephos. Throughout the rainy season, the larvicide eliminated almost all the pre-adult black fly stages on these water courses. At the point in a high onchocercal endemicity area, it also reduced the biting rate by 60% and the Annual Transmission Potential by 72%, i.e., to values corresponding to the lower meso-endemicity threshold. Since these results were obtained at a very unfavourable point from the standpoint of black fly density and onchocerciasis transmission, the authors consider that vector control carried out under these conditions protects the local populations and the Chadian refugees effectively from black fly bites and a risk of severe onchocerciasis.

Long-term beneficial effects of PTCA on segmental early relaxation in disease of the left anterior descending coronary artery

The relationship between regional left ventricular (LV) motion and global pressure relaxation of the left ventricle remains unclear. To clarify the recent concept of segmental early relaxation in coronary artery disease, the authors investigated two groups of patients. In group I, all 12 patients (mean age 47 +/- 7 years) exhibited evidence of a normal heart after an extensive investigation. In group II, 25 patients (55 +/- 7 years) presented an isolated stenosis of the left anterior descending coronary artery, and they underwent a hemodynamic investigation before and after (six to nine months) a durable successful percutaneous transluminal coronary angioplasty (PTCA). After all conventional hemodynamic measurements had been done, a quantitative frame-by-frame analysis of left ventricular wall motion was conducted. The authors' method is derived from that of Ingels, applying to LV cineangiograms filmed in 30 degrees right anterior oblique view at a 50 frames/second rate. Thus segmental wall motion is analyzed in terms of amplitudes (%), velocities of shortening and lengthening in circumferences/second (circ/sec), and times of events (%). Statistical results took into account the reproducibility of the method. Main results regarding the control state of group II consisted of an asynergic motion of the anterior region taking place from end systole to early diastole: 1. Early end of contraction in anterior segments (% of systolic time interval: 88 +/- 14% vs 96 +/- 6% in group I, p less than 0.001) 2. Asynchronism at end systole (maximal velocity of shortening - 0.4 +/- 2.3 circ/sec in anterior segments vs 0.05 +/- 1.9 in inferior segments, p less than 0.02) 3. An early but poor outward anterior wall motion (anterior lengthening at 0.04 sec after the end of ejection 2.9 +/- 10% in group II versus 5.4 +/- 7.2% in group I, p less than 0.05) These abnormalities are strongly correlated with a significant impairment of peak negative diastolic pressure/diastolic time (dP/dt) (1500 +/- 400 mmHg. sec-1 vs 1850 +/- 410 in group I, p less than 0.02). Long-term beneficial effects of PTCA in group II were characterized by an almost complete normalization, both asynergy and relaxation taking place back within the normal range. The authors conclude that in this kind of patient, peak negative dP/dt could be an index of an asynergic segmental motion, this one being correctly analyzed and quantified on LV cineangiograms with our method.