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E Daniels

Publications and source records attributed to E Daniels.

At least 37 records · Page 2Linked to original sources

Dynamic life table model for Aedes aegypti (Diptera: Culicidae): analysis of the literature and model development.

The container-inhabiting mosquito simulation model (CIMSiM) is a weather-driven, dynamic life table simulation model of Aedes aegypti (L.). It is designed to provide a framework for related models of similar mosquitoes which inhibit artificial and natural containers. CIMSiM is an attempt to provide a mechanistic, comprehensive, and dynamic accounting of the multitude of relationships known to play a role in the life history of these mosquitoes. Development rates of eggs, larvae, pupae, and the gonotrophic cycle are based on temperature using an enzyme kinetics approach. Larval weight gain and food depletion are based on the differential equations of Gilpin & McClelland compensated for temperature. Survivals are a function of weather, habitat, and other factors. The heterogeneity of the larval habitat is depicted by modeling the immature cohorts within up to nine different containers, each of which represents an important type of mosquito-producing container in the field. The model provides estimates of the age-specific density of each life stage within a representative 1-ha area. CIMSiM is interactive and runs on IBM-compatible personal computers. The user specifies a region of the world of interest; the model responds with lists of countries and associated cities where historical data on weather, larval habitat, and human densities are available. Each location is tied to an environmental file containing a description of the significant mosquito-producing containers in the area and their characteristics. In addition to weather and environmental information, CIMSiM uses biological files that include species-specific values for each of the parameters used in the model. Within CIMSiM, it is possible to create new environmental and biological files or modify existing ones to allow simulations to be tailored to particular locations or to parameter sensitivity studies. The model also may be used to evaluate any number and combination of standard and novel control methods.

Aedes↗

Dynamic life table model for Aedes aegypti (diptera: Culicidae): simulation results and validation.

The container-inhabiting mosquito simulation model (CIMSiM) is a weather-driven, dynamic life table simulation model of Aedes aegypti (L.) and similar nondiapausing Aedes mosquitoes that inhabit artificial and natural containers. This paper presents a validation of CIMSiM simulating Ae. aegypti using several independent series of data that were not used in model development. Validation data sets include laboratory work designed to elucidate the role of diet on fecundity and rates of larval development and survival. Comparisons are made with four field studies conducted in Bangkok, Thailand, on seasonal changes in population dynamics and with a field study in New Orleans, LA, on larval habitat. Finally, predicted ovipositional activity of Ae. aegypti in seven cities in the southeastern United States for the period 1981-1985 is compared with a data set developed by the U.S. Public Health Service. On the basis of these comparisons, we believe that, for stated design goals, CIMSiM adequately simulates the population dynamics of Ae. aegypti in response to specific information on weather and immature habitat. We anticipate that it will be useful in simulation studies concerning the development and optimization of control strategies and that, with further field validation, can provide entomological inputs for a dengue virus transmission model.

Aedes↗

Effects of interleukin-3 on murine fetal liver hemopoiesis in utero.

The normal regulation of primitive hemopoietic stem cells (PHSCS) throughout development involves locally produced factors and humoral factors. While considerable information is available on the effects of candidate hemopoietic growth factors (HGFs) on postnatal hemopoietic tissues, little is known about the regulatory events of developing hemopoietic stem cells within fetal microenvironments. Fetal hemopoiesis represents expanding populations and may be under different regulatory control mechanisms. The microinjection of purified interleukin-3 (IL-3), a candidate HGF, into 13-day-old mouse fetuses via the yolk sac, allowed us to evaluate its effects on morphogenetic events and, more specifically, on fetal liver populations using quantitative in vitro clonal assays for hemopoietic precursors. In view of the sensitivity of fetal development during the early organogenetic period, considerable care was taken to identify the stress effects of the surgical laparotomy and the microinjection procedure. Control studies, required to distinguish stress effects of surgical laparotomy and microinjection, clearly revealed that the fetal liver is a sensitive organ responding with limited tissue disorganization, reduced cellularity and erythropoietic activity, as monitored 24 h after experimental intervention. The microinjection of 15 units of IL-3 promoted a significant expansion of depleted liver hemopoietic-cell populations and had stimulatory effects on the distribution of connective tissue mast cells and absolute cell numbers, including hemopoietic precursors (erythroid, granulocyte, macrophage, megakaryocyte), compared to controls. These studies suggest that (1) fetal liver hemopoiesis is selectively sensitive to maternal stress but has an effective regenerative capacity to maintain essential hemopoiesis in utero, and (2) fetal hemopoietic cells require an ability to respond to IL-3 early in fetal development.

Animals↗

Spatiotemporal expression of murine carcinoembryonic antigen (CEA) gene family members during mouse embryogenesis.

Carcinoembryonic antigen is a glycosylated protein used as a human tumor marker to assess recurrences of gastrointestinal, breast and lung cancers. This protein is a member of the immunoglobulin supergene family and has been shown to function as a homophilic and heterophilic cell adhesion molecule. We have studied the spatial and temporal expression of two cloned mouse CEA gene family members during development using Northern analyses and in situ hybridization. Transcripts detected by the mouse CEA probes are expressed from 10.5 days post coitum (p.c.) to birth in mouse embryos and fetuses and are present from 16.5 days p.c. to adulthood in intestine and colon as evaluated by Northern analyses. The RNA is also present in many other tissues including meninges, cartilage and bone, blood vessel walls, placenta, dermis, muscle layers of the stomach and intestine and bronchioles of developing mouse embryos and fetuses. This expression pattern is similar to that of proteins of the Transforming Growth Factor beta gene family. The role of mouse CEA gene family members is unclear; however, the localizations of these CEA family members in the mouse embryo and fetus suggest an important functional role during active morphogenesis, a complex process in which cell adhesion molecules are significantly involved.

Animals↗

Passive immunisation of children with bovine colostrum containing antibodies to human rotavirus.

The efficacy of a 10-day course of bovine colostrum with high antibody titre against the four known human rotavirus serotypes in protecting children against rotavirus infection was examined in patients admitted to hospital. Children aged 3 to 15 months were blocked in pairs according to ward accommodation (ie, isolation or open area). Each block contained 1 treated and 1 control child. The allocation to treatment or control (an artificial infant formula) was randomised. 9 of 65 control children but none of 55 treated children acquired rotavirus infection during the treatment period (p less than 0.001). The importance of protecting against rotavirus infection was highlighted by the fact that parents of symptomatic rotavirus-positive children sought medical attention seven times more often than did parents of symptomatic rotavirus-negative children (p less than 0.05).

Administration, Oral↗

Improved techniques for rearing Anopheles freeborni.

Techniques are described for mass rearing Anopheles freeborni. Eggs were incubated overnight at ca. 28 degrees C and then dried. Measured quantities of dried eggs were placed into styrofoam rings floating on the water surface of rearing trays. Water levels in larval rearing trays were kept shallow, and temperature was maintained with heat tapes at ca. 28 degrees C. Larvae were fed once a day on a slurry containing a 3:1:1:1 mixture of guinea pig chow, liver powder, yeast and hog chow. Pupation began on the 7th day after egg hatch, and pupae were harvested on the 8th, 9th and 10th days; ca. 1,700 pupae were harvested/tray. Adults emerged from 85% of the pupae, and about 40% were female. Individual males held in gallon-sized containers inseminated as many as 10 females. Although most sugar-fed males died within 2 weeks after emergence, over 35% of sugar-fed females survived for 3 weeks. Colonies were maintained on defibrinated bovine blood provided in natural membrane prophylactics. There were no significant differences in the number of blood-fed females or in the number of eggs they produced when mosquitoes were offered either guinea pigs or defibrinated bovine blood. Eggs were collected in plastic cups placed in cages. There was less than 6% mortality of eggs when these were dried and stored at 10 degrees C for 6 days.

Animals↗

Comparison of direct electron microscopy and enzyme immunoassay for the detection of rotaviruses in calves, lambs, piglets and foals.

Direct electron microscopy (EM) and enzyme-immunoassay (rotazyme) results for the detection of rotaviruses in 346 enteric specimens from calves, lambs, piglets and foals were compared. The rotazyme test was at least 3 times more sensitive than direct EM in diagnosing infection. Rotavirus antigen was demonstrated by rotazyme in 22% of 280 scour samples and in 27% of 66 samples from non-scouring animals. There was an association between diarrhoea and higher amounts of rotavirus antigen. This prevalence of rotaviruses detected in animals with diarrhoea highlights the significant involvement of other pathogens identified in the study including Eimeria, Cryptosporidia, Escherichia coli, Campylobacter, and other viruses.

Animals↗

Caprine arthritis-encephalitis virus infection of goats in South Australia.

Caprine arthritis-encephalitis virus (CAEV) infection of dairy goats was shown by virus isolation and serology to be widespread in South Australia. CAEV was isolated at necropsy from 24 of 27 dairy goats with swollen joints from 13 herds, and from 9 of 30 liver dairy goats in 7 herds. Virus was isolated most frequently from synovial membranes, and occasionally from mammary glands, mammary lymph nodes, choroid plexus, lungs, spleen, bone marrow, salivary glands, leucocytes, synovial fluid and milk. Antibody to CAEV was detected in the serum of 13 of 17 of the necropsied goats tested in a single-line gel diffusion test, and in another 3 retested with a modified double-line technique. Serum antibody was also demonstrated in 61 of 77 dairy goat herds, many with histories of arthritis. In 1984 to 1986 the annual number of serologically positive serums and proportions of the numbers tested were 134 (40%), 121 (45%) and 42 (18%), respectively. CAEV was isolated from leucocytes of 8 live goats in 6 of these herds. In fibre goats antibody was detected in the serum of 25 Angora and 19 crossbreds (0.1%) from the 33,279 Angora, 1,705 Cashmere, 8,715 crossbred and 904 feral goats tested.

Animals↗

Transluminal angioplasty of the abdominal aorta.

Transluminal angioplasty of the abdominal aorta was performed in 6 women between 49 and 69 years of age with histories of cigarette smoking. Five had a relatively small aorta. This procedure is effective in treating focal aortic stenoses.

Aged↗

A comparison of three-dimensional growth characteristics of cultured primitive marrow stroma derived from genetically anemic and normal mice.

This study examines the ultrastructure of mouse defective marrow stroma when cultured as a three-dimensional organization of cells. Gelfoam sponges impregnated with agar medium allowed the three-dimensional organization of newly formed stromal cells derived from the crevices of marrow-depleted bones of Steel mutant mice (Sl/Sld) with defective stroma and also from mice with normal stroma (Sl +/+, W/Wv, and W +/+. Ultrastructural comparisons of 5- to 14-day cultures revealed that the mutant defective stromal cells developed normally, viz. i) proliferated and formed a three-dimensional organization of stroma, ii) stimulated residual hemopoietic precursors to form myeloid cells, and iii) formed a variety of stromal cell types characterized by variable quantities of Golgi bodies and ER, glycogen, filaments, and round cytoplasmic granules. The Steel-Dickie strain, however, included bacilliform electron-dense granules in both normal and mutant stroma. The only ultrastructural deficiency in Sl/Sld stroma was the absence of a category of "activated" cells that occurred within normal cell populations.

Anemia↗

The diagnosis of meniscus pathology.

A study of 281 patients evaluated for a meniscus pathologic condition was performed to assess the accuracy of the clinical diagnosis and arthrogram and delineate the role of arthroscopy. Following the clinical examination, the surgeon stated his level of confidence in his diagnosis, as did the radiologist in his interpretation of the arthrogram. In 134 cases inspected by arthroscopy or arthrotomy, the clinician proved to be correct 74% of the time, and the arthrogram accuracy in evaluating the medial meniscus was 89%; the majority of the errors were false positive diagnoses. In the 82 meniscus tears in which an arthrogram was performed the diagnosis was made in 80 cases, or 98%. The arthrogram accuracy in the lateral compartment was 81%; however, of the 31 lateral meniscus tears in which an arthrogram was performed, a positive diagnosis was yielded by arthrogram in only ten cases. In 34 lateral meniscus tears, a positive clinical diagnosis was made in only 12 cases. Arthroscopy was performed in 117 cases and proved helpful in patient management in 65 cases (55%). Arthroscopy was performed in 25 patients with lateral meniscus tears and a diagnosis of a lateral meniscus tear was made in all cases. The observations suggest that prior to performing an arthrotomy, arthroscopic examination of the knee should be performed routinely in patients suspected of having meniscus tears.

Adolescent↗

Characteristics of synthesis and distribution of 3H-fucose-containing glycoproteins by marrow stromal cells cocultured with hemopoeitic cells in gelfoam sponges. An electron microscope radioautographic study.

Gelfoam sponge cultures of stromal cells, derived from guinea pig marrow-depleted bone fragments, support the growth of myeloid precursors in the absence of exogenous stimulants. EM radioautographic studies were undertaken to identify active synthesis and distribution of 3H-fucose-containing glycoproteins within the 3-D organization of cultured hemopoietic tissue. Labeling of 5-14 day cultures with tritiated fucose for 20 min revealed an intracellular localization of silver grains over the endoplasmic reticulum and Golgi bodies of all stromal cells. Cumulative labeling (1-48 h) of similar cultures indicated that (i) silver grains subsequently accumulated in plasma membranes, large cytoplasmic granules and also within lipid droplets, (ii) primitive and myeloid cells were also labeled. Localized extracellular concentrations of silver grains were facilitated by the multiple inter-stromal cell contacts and by the accumulation of fine labeled cytoplasmic processes. Mechanisms whereby stromal cells may actively influence physiochemical changes in the hemopoietic inductive microenvironment are suggested.

Animals↗