Inhibition of antibodies to CD3 surface antigen and phytohemagglutinin-mediated T cellular responses by inhibiting Ca2+/phospholipid-dependent protein kinase activity with the aid of 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine dihydrochloride

Ca2+/phospholipid-dependent kinase activity (C-kinase) plays an important second messenger role in T lymphocyte responses initiated by the cluster of differentiation (CD3) complex and presumably also lectinic receptors. During treatment with submitogenic or mitogenic amounts of phytohemagglutinin, as well as with anti-CD3 monoclonal antibody and 12-O-tetradecanoyl 13-phorbol acetate, the enzyme was intracellularly redistributed between the cytosol and the surface membrane. Submitogenic amounts of lectin and anti-CD3 were ineffective in inducing proliferation unless exogenous interleukin 2 (IL-2) was supplied, implying that even though IL-2 receptors were expressed, additional signals were required for IL-2 production. This would also indicate that there is a direct relationship between activation of C-kinase and expression of IL-2 receptors. The importance of C-kinase was further substantiated by the ability of 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine dihydrochloride (H7), a potent inhibitor of this enzyme, to interfere with IL-2 receptor expression and cellular [methyl-3H]thymidine uptake during primary activation. The drug concentration at which these cellular responses were inhibited by 50% was about the same as that which decreased c-kinase activity by 50% in vitro. H7 also prevented anti-CD3-induced translocation in intact cells. This effect may be related to competition with the phosphatidylserine binding site, which is important for membrane attachment. This drug apparently also interferes with the active center of the enzyme as demonstrated by its ability to inhibit Ca2+/phospholipid-independent phosphorylation of protamine sulfate. This additional mode of inhibition may be important in suppressing intact cell responses under circumstances during which the enzyme displacement to the membrane is nonphysiologic in nature, e.g., during treatment with 12-O-tetradecanoyl 13-phorbol acetate.     

Influence of group size on water imbibition by Hodotermes mossambicus alate termites

When newly emerged Hodotermes mossambicus alates are confined in pairs they drink almost half of their weight in water. Groups on the other hand do not exhibit this behaviour. The results obtained with individuals held in solitary confinement were intermediate between those obtained with pairs and groups. The imbibed water is stored in two large ‘water-sacs’ which extend well into the abdomen. Samples of the fluid from the ‘water-sacs’ had a relatively high freezing point and also contained far less Folin phenol positive material and Na⁺ and K⁺ than haemolymph.     

Four new Psocoptera from Lebanese amber (Insecta: Psocomorpha: Trogiomorpha)

Four new trogiomorphan Psocoptera are described from the Lower Cretaceous Lebanese amber, viz. Bcharreglaris amunobi n. gen., n. sp., Setoglaris reemae n.gen., n. sp., Libanoglaris chehabi n.sp., and Libanoglaris randatae n. sp. These discoveries show that the Lower Cretaceous biodiversity of the Trogiomorpha was very high.     

First fossil occurrence of the jewel damselflies (Odonata: Chlorocyphidae): a new species from the Late Miocene of Styria,Austria

The first fossil representative of the jewel damselflies (Calopterygoidea: Chlorocyphidae), a family of large, prominent, and often brilliantly colored Old World tropical Zygoptera, is described and figured. Chlorocypha cordasevae n. sp. was recovered from the Late Miocene (Early Pannonian, Serravalian to Tortonian, c.11 Ma) locality of Paldau, in the Styrian Basin, Austria. The fossil seems to be related to the African genus Chlorocypha Fraser, and within a larger group of African genera also including Stenocypha Dijkstra, Africocypha Pinhey, and Platycypha Fraser, and collectively set apart from southern Asiatic genera. The discovery of a central European species of Chlorocypha as recently as the Late Miocene reveals a much wider range to the family than its generally disjunctive modern distribution, demonstrating a Neogene contraction to their range, likely in connection with climatic cooling, drying, and developing seasonality. Modern chlorocyphids live under warm, humid climates, and the presence of C. cordasevae in the Pannonian fauna of Paldau further corroborates such a subtropical paleoclimate for the locality at that time.     

New biting midges from the Cretaceous amber of Lebanon (Diptera: Ceratopogonidae)

New Ceratopogonidae from the Early Cretaceous amber of Hammana (Central Lebanon) are studied. Five new species (Lebanoculicoides daheri sp. nov., Protoculicoides krzeminskii sp. nov., Archiaustroconops annae sp. nov., Archiaustroconops hammanensis sp. nov., and Archiaustroconops dominiakae sp. nov.) are characterized, described, illustrated, and compared with other Cretaceous taxa. New keys for species of the three genera Lebanoculioides, Protoculicoides, and Archiaustroconops, but also for all genera of Lebanese fossil biting midges, are proposed.     

A new Microphorites in the Lower Cretaceous amber of the Southwest of France (Diptera: Dolichopodidae, “Microphorinae”)

A new deposit of Lower Cretaceous amber, found in Charente-Maritime (SW France) has yielded an important entomofauna with numerous arthropod associations characteristic of moist ground. We describe a new species of Dolichopodidae: ‘Microphorinae’(Diptera: Empidoidea), Microphorites deploegi n. sp. on the basis of seven male and female specimens of exceptional state of preservation. This genus was previously only known from Lebanese amber of the Lower Cretaceous. The present discovery supports a reconstruction of the palaeoenvironment as a sandy beach along the sea, under a warm climate.     

Three-Dimensional Protein Fold Determination from Backbone Amide Pseudocontact Shifts Generated by Lanthanide Tags at Multiple Sites

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Diversity and Epidemiology of Mokola Virus

Mokola virus (MOKV) appears to be exclusive to Africa. Although the first isolates were from Nigeria and other Congo basin countries, all reports over the past 20 years have been from southern Africa. Previous phylogenetic studies analyzed few isolates or used partial gene sequence for analysis since limited sequence information is available for MOKV and the isolates were distributed among various laboratories. The complete nucleoprotein, phosphoprotein, matrix and glycoprotein genes of 18 MOKV isolates in various laboratories were sequenced either using partial or full genome sequencing using pyrosequencing and a phylogenetic analysis was undertaken. The results indicated that MOKV isolates from the Republic of South Africa, Zimbabwe, Central African Republic and Nigeria clustered according to geographic origin irrespective of the genes used for phylogenetic analysis, similar to that observed with Lagos bat virus. A Bayesian Markov-Chain-Monte-Carlo- (MCMC) analysis revealed the age of the most recent common ancestor (MRCA) of MOKV to be between 279 and 2034 years depending on the genes used. Generally, all MOKV isolates showed a similar pattern at the amino acid sites considered influential for viral properties.