Peritrophic membrane of the 2d type in females of the genus Aedes]

In the females of bloodsucking mosquitoes of the genus Aedes there was recognised a secretory activity of the cells of the external wall of the cardial portion of the intestine. The secretion excreted according to the macroapocrine type forms in the cardial cavity a peritrophic membrane of the 2-nd type. A difference in the development rate of the membrane in the species studied was noted.     

The Origin of the Northern Palaearctic Fauna of Bloodsucking Insects,by the Example of Fleas (Siphonaptera), Mosquitoes (Diptera: Culicidae), and Blackflies (Diptera: Simuliidae)

The territory of Fennoscandia and northwestern European Russia was released from the glacier cover in the Upper Pleistocene and has been recolonized by bloodsucking insects during the last 11 thousand years. The sources of formation of the Northern Palaearctic fauna of such groups of bloodsucking insects as fleas (Siphonaptera), mosquitoes (Culicidae), and blackflies (Simuliidae) were different in the postglacial period. One of the sources was the fauna of the ancient Mediterranean and southern Europe, while others were the faunas of northeastern China and Primorye. In turn, the two latter sources are closely related to the ancient faunal centers of the East Asian Subregion of the Palaearctic and also of the Indomalayan Region. Besides, some species and genera have spread from the West American Subregion of the Nearctic through Beringia.     

Lack of an effect from repeated blood sucking by mosquitoes on their infectivity with the causative agent of malaria

The lack of repeated bloodsucking does not affect essentially the infection of Ae. aegypti mosquitoes with malaria agent, P. gallinaceum.     

Fauna and biology of the mosquitoes (Culicidae) of the Chara valley (Chita Province)

The specific composition and the nature of domination of bloodsucking mosquitoes from the Charskaya hollow were studied. The abundance dynamics of attacking females was registered by means of Berezantzev's bell. Data were obtained on the hatching sites of mosquitoes and peculiarities of seasonal adaptation of some species in connection with the availability of various landscapes with different microclimatic conditions.     

Bloodsucking dipteran insects (Diptera) attacking humans and animals (the “gnus” complex) in northwestern Russia: I. General characteristics of the fauna

The fauna of bloodsucking Diptera of northwestern Russia comprises 226 species of mosquitoes (Culicidae), biting midges (Ceratopogonidae), black flies (Simuliidae) and horseflies (Tabanidae). In particular, Culicidae include 41 species from 10 subgenera of 5 genera of 2 subfamilies. Simuliidae are represented by 110 species of 23 genera, belonging to 6 tribes of 2 subfamilies; the genus Culicoides of the Ceratopogonidae, by 31 species; and Tabanidae, by 44 species of 7 genera from 2 subfamilies. There is a necessity of elaboration and application of more advanced forms of information storage and field data standardization. In the Zoological Institute, Russian Academy of Sciences, a special database on the bloodsucking insects of Russia is created in the DBMS Access. A list of abundant bloodsucking species of mosquitoes, biting midges, black flies and horseflies is included. A brief synopsis of bibliography of investigations of the bloodsucking dipterans from northwestern Russia is given, provided with a list of more then 190 publication.     

Biotopic distribution and conditions for development of bloodsucking mosquitoes from the subfamily culicinae in Daghestan

The distribution of 21 species of bloodsucking mosquitoes was studied in Daghestan. The relationships between the distribution and number of mosquitoes and the environmental conditions were determined. The hydrological regime, specific features of overgrowing and warming of water bodies affect the distribution of mosquito larvae.     

Bloodsucking dipterans (Diptera: Ceratopogonidae,Culicidae, Simuliidae,Tabanidae) of the Kurgala Peninsula,Leningrad Province

The fauna of bloodsucking dipterans of the Kurgala Peninsula comprises 73 species, 34 of which belong to mosquitoes (Culicidae), 18 to blackflies (Simuliidae), 5 to biting midges (Ceratopogonidae, genus Culicoides), and 16 species to horseflies (Tabanidae). Nine species of the bloodsucking dipterans found on the Kurgala Peninsula are new to Leningrad Province, 6 of them being also recorded for the first time for the neighboring territories of Estonia and southern Finland.     

A purified cellular extract accelerates the cell cycle in Physarum polycephalum

Plasmodia of the myxomycete Physarum polycephalum (strain Cl) were collected at different times during the cell cycle and extracts were prepared from homogenates using a buffer optimized for microinjection into plasmodial veins. These extracts were injected into plasmodia during the first 3 h of the cell cycle. The time of the following mitosis was monitored and compared with that of the buffer-injected controls. Extracts of plasmodia homogenized 45 min before late telophase accelerated the onset of mitosis in the injected plasmodium up to 70 min, i.e., an advance of 10-14% compared to the 8- to 10-h cell cycle duration of the controls. The accelerating activity vanished completely after heating, freezing, or protease digestion, thus indicating the peptide nature of the active agent. Purification of the active compound by means of gel filtration revealed a molecular mass of about 2500 Da. The active portion of the extract was further fractionated by HPLC and the activity determined in a single peak.     

Effect of microsporidians on the caloric value of the larval tissues of blood-sucking mosquitoes

It has been established that the infection of larvae of bloodsucking mosquitoes of the genus Aedes with microsporidians of Thelohania opacita Kudo results in changes of the size and weight of an infected individual, increase of water content in its organism and loss of a considerable part of energetic reserves.     

Means of the formation of gonotrophic relations in blood-sucking Diptera

Gonotrophic relations in low and higher bloodsucking Diptera are fundamentally different that results from an initial type of feeding and trophic behaviour. Trophic behaviour of low dipterous hematophages and gonotrophic harmony peculiar to them can be traced from entomophagy, that is from the predatory mode of life on account of small insects. By the type of the trophic behaviour low bloodsucking Diptera are predators with a typical moment contact with the prey. More primitive is a type of gonotrophic harmony characteristic of hunters for diffusely spread prey (incomplete blood portion provides the maturation of incomplete portion of eggs). Hunting for diffusely spread prey is characteristic of entomophages too. The appearance of gregarious ruminants facilitates the possibility of repeated contacts with prey and blood satiation threshold increases. This is a higher type of gonotrophic harmony providing a maximum realization of potential fecundity. The initial saprophagy of higher Diptera is associated with another type of trophic behaviour (long contact with food substratum) that is a prerequisite for quite a different way of evolution of host-parasite relationships in higher Diptera. This leads to more close connections with the host and excludes gonotrophic harmony. Females were the first to begin the exploitation of vertebrate animals. This is connected with the peculiarities of their behaviour during egg laying such as the stay near animals for laying eggs into fresh dung. Autogeneity, nectarophagy and aphagia are homologous phenomena which reflect the loss of an animal component of food or both components at the level of non-specialized saprophagy rather than secondary loss of bloodsucking. The scheme of gonotrophic relations is given.     

A double-blinded, placebo-controlled trial of garlic as a mosquito repellant: a preliminary study

The hypothesis that the ingestion of garlic provides protection against bloodsucking pests such as mosquitoes was investigated using a randomized, double-blinded, placebo-controlled crossover study. Subjects were asked to consume either garlic (one visit) or a placebo (the other visit). They were then exposed to laboratory-reared Aedes aegypti (Linnaeus) (Diptera: Culicidae). The numbers of mosquitoes that did not feed on the subjects, the number of mosquito bites, the weights of the mosquitoes after feeding and the amounts of blood ingested were determined. The data did not provide evidence of significant systemic mosquito repellence. A limitation of the study is that more prolonged ingestion of garlic may be needed to accomplish repellence.     

Landscape and zonal distribution of bloodsucking mosquitoes and horseflies (Diptera: Culicidae,Tabanidae) in the northeastern Russian Plain

Analysis of landscape and zonal changes in the species diversity and abundance of 34 species of bloodsucking mosquitoes and 42 species of horseflies in the northeastern Russian Plain was carried out. The species diversity of both families is reduced from south to north. Two steps of faunistic depletion can be revealed: at the boundary of the middle and northern taiga (both mosquitoes and horseflies) and at the boundary of the extreme northern taiga and the forest-tundra (horseflies only). Species whose northern and southern distribution boundaries lie within the territory studied are listed.     

Assemblages of bloodsucking mosquito larvae (Diptera: Culicidae) in water bodies of the northern Kulunda steppe

The population structure of bloodsucking mosquito larvae in temporary and constant water bodies of the northern Kulunda steppe was investigated. The seasonal dynamics of the population density, the number of species in different types of reservoirs, and average density of each species are given. The productivity of water reservoirs in relation to mosquitoes of the family Culicidae is analyzed. The basic factors affecting the distribution of larvae of dominant species between different water bodies were revealed. The degree of correlation between the structure of bloodsucking mosquito larva assemblages and the type of the reservoir was established.     

Pathology of Anopheles stephensi after infection with Plasmodium berghei berghei. II. Changes in amino acid contents.

Infection with Plasmodium berghei results in the disease of a relatively high percentage of mosquitoes depending on the experimental conditions. The damage caused by the parasites may be so severe that the host dies. It can also become manifest for instance in a change in the amino acid content of the mosquito homogenate. The amino acid content of mosquitoes fed on a glucose solution, normal mouse blood, or the blood of infected mice was analysed qualitatively and quantitatively over a period of 14 days. The amino acids lysine, phenylalanine, proline, threonine, and tyrosine are always found in higher concentrations in infected mosquitoes. The content of leucine (and/or isoleucine) increased from the 6th day and glutamic acid from the 9th day compared to the controls. Lower concentrations were found for alanine, aspartic acid, glycine, and serine as compared to uninfected mosquitoes. Further investigations on this subject might help to find the causes for the susceptibility or resistance of individual mosquitoes to plasmodia.     

Experimental study of the routes of transmission of Microsporidia in blood-sucking mosquitoes from southwestern Siberia

Experiments were conducted on the artificial infection of larvae of 8 species of bloodsucking mosquitoes (Aedes diantaeus, A. punctor, A. cinereus, A. flavescens, A. aegypti, Culex pipiens, Anopheles messeae, Anopheles atroparvus) with spores of Amblyospora opacita var. sibirica, Parathelohania costatus sp. n., P. obesa, P. anophelis. Negative results were obtained in all experiments.     

Effect of stretching training on the viscoelastic properties of human tendon structures in vivo.

The purpose of this study was to examine whether stretching training altered the viscoelastic properties of human tendon structures in vivo. Eight men performed the stretching training for 3 wk. Before and after the stretching training, the elongation of the tendon and aponeurosis of medial gastrocnemius muscle was directly measured by ultrasonography while the subjects performed ramp isometric plantar flexion up to the voluntary maximum, followed by a ramp relaxation. The relationship between the estimated muscle force (Fm) and tendon elongation (L) during the ascending phase was fitted to a linear regression, the slope of which was defined as stiffness of tendon structures. The percentage of the area within the Fm-L loop to the area beneath the curve during ascending phase was calculated as an index representing hysteresis. To assess the flexibility, the passive torque of the plantar flexor muscles was measured during the passive stretch from 0 degrees (anatomic position) to 25 degrees of dorsiflexion with a constant velocity of 5 degrees/s. The slope of the linear portion of the passive torque-angle curve during stretching was defined as flexibility index. Flexibility index decreased significantly after stretching training (-13.4 +/- 4.6%). On the other hand, the stretching training produced no significant change in stiffness but significantly decreased hysteresis from 19.9 +/- 11.7 to 12.5 +/- 9.5%. The present results suggested that stretching training affected the viscosity of tendon structures but not the elasticity.     

Realization of antimalarial measures in the period of eradication of the consequences of a flood in the Stavropol Territory in 2002

As the result of the high flood, an increase in the area of anopheligenic water reservoirs occurred on the inundated territories, which created favorable conditions for the proliferation of Anopheles mosquitoes, the vectors of malarial plasmodia, thus creating the threat of the formation of the local sources of malaria in case of its penetration from other regions unfavorable with respect to this disease. In the affected towns and regions hydrotechnical measures aimed at decreasing the surface of anopheligenic water reservoirs, as well as measures aimed at the decrease in the number of the larval and imaginal stages in the development of mosquitoes, were taken, which made it possible to prevent the probable epidemiological aggravations in malaria.     

Immunocytochemistry of the acellular slime mold Physarum polycephalum

Abstract. The polygonal arrangement of actomyosin fibrils in different stages of the acellular slime mold Physarum polycephalum is correlated with morphogenetic processes at the cell surface. Light and electron microscopic investigations on both endoplasmic drops and thin-spread small plasmodia demonstrate that the differentiation of a polygonal pattern depends on a transient deficiency of plasma membrane invaginations.
Glycerol-extracted specimens show condensation and drastic spatial changes in the organization of the polygonal net after addition of ATP, thus indicating contractile properties of this system. Observations with the polarizing microscope reveal rhythmic changes in fibrillar birefringence intensity corresponding to the protoplasmic streaming activity, i.e., birefringence increases during contraction and decreases during relaxation. Cell fusion experiments, local irradiation with blue light (450 nm), and chemical treatment by impeding the mitochondria1 function with DNP (2,4-di-nitrophenol) demonstrate morphological as well as physiological interdependences of the actomyosin system, the motive force generation, and the expression of a locomotor polarity in plasmodia of Physarum polycephalum.     

Studies on infections with the Berok strain of Plasmodium cynomolgi in monkeys and mosquitoes

Infections with the Berok strain of Plasmodium cynomolgi were induced in Macaca mulatta, Macaca fascicularis, Macaca nemestrina, Aotus lemurinus griseimembra, Aotus azarae boliviensis, and Saimiri boliviensis monkeys. Transmission was obtained with sporozoites developing in Anopheles peditaeniatus, Anopheles maculatus, Anopheles quadrimaculatus, Anopheles culicifacies, and Anopheles dirus mosquitoes. This strain of P. cynomolgi offers significant potential for a number of experimental studies. The parasite induces high-density parasite counts in both Old World and New World monkeys; rhesus monkeys readily support the development of gametocytes infectious to different anopheline mosquitoes routinely maintained in the laboratory; the gametocytes are infective to laboratory-maintained Anopheles albimanus, a vector rarely susceptible to plasmodia of Old World monkeys; encapsulated oocysts are produced in An. culicifacies as well as in Anopheles gambiae; and the parasite has been adapted to long-term in vitro culture.     

Blood-sucking mosquitoes (Culicidae) of southeastern and western Evenkia

24 species of bloodsucking mosquitoes of the genera Aedes and Culiseta are recorded from south-eastern and western Evenkia situated in Central Siberia, of which C. Bergrothi, A. increpitus, A. mercurator and A. riparius are first reported for Evenkia. The specific composition, dominant species in water bodies and air, phenology, the activity in attacking man and reindeer, parameters of external factors typical of the attacking of warmblooded animals are noted for each investigated area.