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Detection of dengue virus from field Aedes aegypti and Aedes albopictus adults and larvae.

Mosquito adults and larvae were collected from dengue high risk areas and transported to the laboratory for identification. Identified mosquitos were pooled according to the species, date and locality and stored at -70 degrees C. A total of 1,385 pools of Aedes albopictus and 267 pools of Ae. Aegypti were collected from major towns in 12 states in Peninsular Malaysia. Virus isolation was carried out using cell culture (C6/36 clone) of Ae. albopictus and detection of dengue virus by the peroxidase anti-peroxidase staining. All positive isolations were further re-confirmed by the reverse transcr…

Chitinase genes expressed by infective larvae of the filarial nematodes, Acanthocheilonema viteae and Onchocerca volvulus.

State-specific products of 220 and 75 kDa were identified by metabolic labelling of infective larvae of the filarial nematode Acanthocheilonema viteae in ticks. Synthesis was temperature sensitive, occurring at 27 degrees C but not at 37 degrees C. These products were secreted 3-6 days after leaving the vector during post-infective development, but subsequent expression was not detected. The smaller protein with a pI of 6.2, was purified by two-dimensional electrophoresis and the N-terminal amino acid sequence was derived. This provisionally identified the protein as a chitinase, which was con…

Ultrastructural colocalization of phosphorylcholine and a phosphorylcholine-associated epitope in first-stage larvae of Trichinella spiralis.

Although the presence of phosphorylcholine (PC) in Trichinella is well established, the structures of the TSL-4 antigens that bear this epitope are unknown. A subset of TSL-4 antigens (TSL-8 antigens) has been reported to be absent from the surface of first-stage T. spiralis larvae. We report experiments with a monoclonal antibody (mAb US2) developed in mice with a relative inability to produce antibodies to PC. In immunoblotting, mAb US2 and anti-PC mAb (BH8) showed apparently identical binding patterns. In addition, we used an immunogold double-labeling technique to study the anatomical dist…

Specific antibody patterns of Wistar rats inoculated with third stage larvae of Anisakis simplex.

Levels of excretory-secretory (ES)-specific antibody were measured in Wistar rats inoculated with 1, 5, or 20 third stage larvae (L3) of Anisakis simplex. Primary inoculation induced ES-specific IgM and IgG titers, paralleling inoculum size. Secondary inoculations resulted in an IgM and IgG titer augmentation in 1 or 5 larvae-inoculated animals to levels comparable to those of animals inoculated with 20 larvae, but titers in high inoculum animals did not increase upon secondary inoculation. Primary inoculation induced low ES-specific IgE antibody titers. However, secondary inoculation produced…

Demonstration of the target molecule of a protective IgE antibody in secretory glands of Schistosoma japonicum larvae.

We have demonstrated that a mouse monoclonal IgE antibody, SJ18 epsilon.1, recognizes a 97 kDa surface molecule (Sj97) of Schistosoma japonicum larvae and that the antibody induces partial but significant protection against the skin to lung-stage of S. japonicum infection. The antibody stimulates eosinophil- and macrophage-mediated killing of schistosomula in vitro. In the present study, we isolated the putative full-length cDNA of Sj97 by screening a lambda gt11 cDNA library from S. japonicum adult worms with SJ18 epsilon.1. The predicted amino acid sequence of the cDNA showed highly signific…

Immunization against experimental trichinosis using T. spiralis larvae and hydatid fluid antigens.

Immunization of mice against T. spiralis infection using T. spiralis larval glycoproteins as homogenous antigen and crude hydatid fluid as heterogenous antigen showed a marked reduction in larvae burden and a significant rise of serum IgE in immunized mice infected with T. spiralis larvae as compared with control group. More reduction was observed with immunization with homogenous T. spiralis larval antigen compared with heterogenous hydatid fluid antigen. The reduction in larval burden with rise of serum IgE begins after the third week of immunization.

Trichinella spiralis: the effect of specific antibody on muscle larvae in the small intestines of weaned rats.

Weaned rats were passively immunized with rat IgG2c monoclonal antibodies previously shown to protect infant rats against challenge with Trichinella spiralis. Although the antibodies did not protect rats against infection, the course of larval establishment in the intestine was altered in a way that has not been described previously. Specifically, larvae that invaded the epithelium were inhibited from migrating from intestinal tissue into saline during the standard recovery procedure. The inhibition was reversed at a time coincident with the first moult. Whole serum from infected rats had a si…

Prevention of cutaneous myiasis caused by screw worm larvae (Cochliomyia hominivorax) using ivermectin.

During March of 1991 and 1992, four trials were carried out in the central area of Argentina to evaluate the efficacy of ivermectin in the prevention of myiasis caused by Cochliomya hominivorax larvae. In the first trial 24 steers were artificially wounded, in the second and third trial, 36 and 20 bull calves were castrated while in the fourth trial, 30 newborn calves were used. On day 0, half of the animals of each trial was treated with ivermectin (200 micrograms/kg) and the rest remained as untreated controls. None of the treated animals sustained a screw-worm larva infestation, but 3 of 12…

On the infectivity of early third-stage Brugia larvae isolated from the abdomen of Aedes aegypti.

Third-stage larvae (L3) of Wuchereria bancrofti, Brugia malayi and B. pahangi are known to be recovered not only from the head and thorax but also from the abdomen of dissected vector mosquitoes. For epidemiological reasons, was of interest to determine whether L3 larvae from the abdomen of the vector would be infectious for the final host. Early abdominal L3 larvae of B. pahangi isolated as early as on day 7 post-infection (p.i.) from Aedes aegypti were injected s.c. into five male Meriones unguiculatus. Four of the five jirds were microfilaria-positive after 67 days.

Inhibition of carbohydrate uptake of Onchocerca volvulus infective larvae (L3) by effector cell constituents.

The in vitro killing of Onchocerca volvulus infective third stage larvae (L3) by components of their human hosts' defence mechanisms is not well documented, as no suitable assay exists. Motility is inappropriate as a criterion of larval viability because of the unsteady winding movements of L3. In the present study, a metabolic parameter for larval viability, the uptake of [3H]2-deoxy-D-glucose, was evaluated. To demonstrate the reproducibility and validity of this test, the oxygen radical hydrogen peroxide (H2O2) was applied to viable L3 and the death of L3 demonstrated by a 90% reduction in …

Characterization of the intracellular melanization response in Anopheles quadrimaculatus against subperiodic Brugia malayi larvae.

Intracellular melanization, a defense or an immune response in the thoracic muscle cells, was investigated in a refractory strain of Anopheles quadrimaculatus infected with larvae of Brugia malayi. In mosquitoes fed on B. malayi-infected jirds, intracellular melanization against first-stage larvae (L1) was better expressed when fewer than 40 microfilariae reached the thoracic muscle cells than when more than 40 microfilariae reached the thoracic muscle cells. This result suggests that when large numbers of microfilariae invade the thoracic muscle cells, the immune response of the mosquito may …

Cutaneous myiasis caused by tumbu fly larvae, Cordylobia anthropophaga in southwestern Saudi Arabia.

Seven cases of human cutaneous myiasis caused by maggots of the tumbu fly, Cordylobia anthropophaga are reported from Asir region, southwestern Saudi Arabia. Boil-like swellings infested with individual fly larvae, varied from one to four and occurred in both unprotected and usually protected areas of the skin. Twenty five fly maggots were retrieved from separate furunculoid lesions on the body surface of a massive case of a 4-year old boy. The present observations confirm that this calliphorine species is not restricted to tropical Africa.

Trichinella spiralis: major histocompatibility complex-associated elimination of encysted muscle larvae in swine.

A heretofore undescribed host-mediated reactivity against encapsulated muscle larvae (ML) of the nematode Trichinella spiralis is reported. Inbred miniature swine (NIH minipigs) of three independent SLA phenotypes, which received a primary oral dose of 300 T. spiralis ML, successfully resisted a secondary infection of 10,000 ML; however, only pigs of the SLAa/a phenotype exhibited an unusual and highly significant reduction in the numbers of encysted ML from the primary infection (P less than 0.0003). This initial anti-encysted ML reactivity was confirmed in subsequent trials by comparing the …

[Fishes in the lower reaches of the Ob River studied for their infectiousness with helminth larvae of medical significance].

The data on fish infection with Diphyllobothrium and Opisthorchis larvae in the lower Ob were specified. There is a tendency to decrease fish infection with Diphyllobothrium plerocercoids and preserve infection with Opisthorchis metacercariae.

Передача вируса лихорадки Рифт-Вэлли взрослыми комарами после поглощения вируса личинками.

Мы изучили способность Culex pipiens, Aedes Crossluteolus и Ae. mcintoshi, подвергаясь воздействию личинок в печени от вируса лихорадки Рифт-Вэлли (RVF), стать инфицированным и трансстадиально передавать вирус взрослым, а взрослым передавать вирус путем укуса хомякам. После воздействия личинок 9% (5/54) взрослых Сх. пипиенов и 8% (38/505) видов взрослых ээ. (Неомеланиконион) были заражены. Все инфицированные Cx. pipiens и около половины инфицированных Ae. Crocluteolus и Ae. mcintoshi перенес вирус RVF, укусив хомяков. Показатели передачи инфекции от комаров, инфицированных в устной форме в кач

Совпадение в аннотации оригинала
We studied the ability of Culex pipiens, Aedes circumluteolus, and Ae. mcintoshi, exposed as larvae to liver tissue from a Rift Valley fever (RVF) virus-infected hamster, to become infected and transstadially transmit virus to the adult and for the adults to transmit virus by bite to hamsters. After exposure as larvae, 9% (5/54) of adult Cx. pipiens and 8% (…

Isolation and characterization of expression cDNA clones encoding antigens of Onchocerca volvulus infective larvae.

The isolation of recombinant cDNA clones expressing antigens found in Onchocerca volvulus infective larvae is described. To isolate such clones, an expression cDNA library constructed from adult O. volvulus RNA was screened with antiserum raised against infective larvae. One clone, designated lambda RAL-1 was characterized further. The recombinant antigen produced by lambda RAL-1 stimulates proliferation of peripheral blood mononuclear cells from O. volvulus infected humans. Lambda RAL-1 is derived from a 1450 bases message that encodes a protein with an apparent molecular weight of 42,000 in …

Serum enzymes and worm load in mice infected with repeated doses of Ancylostoma caninum larvae.

The alterations of serum enzymes induced in the host system of swiss albino mice by infection with Ancylostoma caninum larvae have been studied in multiple doses of infection. It was found that the level of transaminases, alkaline phosphatase and amylase increased significantly throughout the infection period when compared with controls. In infected animals, increase of enzymes was influenced by the host-parasite interactions caused due to the retained concentration of larval antigens.