Strategy for development of a pre-erythrocytic Plasmodium falciparum DNA vaccine for human use

Data generated in the Plasmodium yoelii rodent model indicated that plasmid DNA vaccines encoding the P.yoelii circumsporozoite protein (PyCSP) or 17 kDa hepatocyte erythrocyte protein (PyHEP17) were potent inducers of protective CD8+ T cell responses directed against infected hepatocytes. Immunization with a mixture of these plasmids circumvented the genetic restriction of protective immunity and induced additive protection. A third DNA vaccine encoding the P. yoelii sporozoite surface protein 2 (PySSP2) also induced protection. The P. falciparum genes encoding the homologues of these three protective P. yoelii antigens as well as another P. falciparum gene encoding a protein that is expressed in infected hepatocytes have been chosen for the development of a human vaccine. The optimal plasmid constructs for human use will be selected on the basis of immunogenicity data generated in mice and nonhuman primates. We anticipate that optimization of multi-gene P. falciparum DNA vaccines designed to protect against malaria by inducing CD8+ T cells that target infected hepatocytes will require extensive clinical trials during the coming years.     

Regulation of chromatic induction by neighboring images

We deal with the regulation of chromatic contrast when the induction of a second stimulus (one of five neighboring surrounds) opposes the induction from a first stimulus (one of two remote vivid peripheral fields). Using a hue cancellation judgment, we show that, although every neighboring surround that we used has the same average chromatic content, the resulting color appearance of the target differs between surrounds, and this may be ascribed to the spatiochromatic organization of the surround. So, rather than the chromatic contrast amplitude or the frequential structure of the surround, it is the structure of proximity that matters.     

A comparison of current methods of poliovirus concentration from tap water

The efficiency of concentration of poliovirus from Jerusalem tap water was investigated for several types of “electronegatively-charged” and “electropositively-charged” microporous filters. In addition, the efficiency of organic flocculation as a procedure for reconcentrating poliovirus from filter eluates was investigated. The Balston and Cox filters had similar recovery efficiencies from tap water, with recovery of approx. 90% of the input virus, both after filtration and after organic flocculation. Decreasing the concentration of beef extract in the eluent from 3 to 1% did not negatively influence virus recovery. However, recovery of low virus numbers from large volume samples by Cox filters was variable. Balston filters were used in a series of high volume experiments to test the efficacy of the tentative standard method for virus recovery using a proportioner pump with two additive pumps. The method was inefficient without a simple modification, the addition of a second mixing chamber, which increased the virus recovery to an acceptable level. The Zeta Plus electropositively-charged type of filter had a high efficiency of virus recovery in the eluate, but approximately half of the virus was lost during organic flocculation. This may indicate the need for modification of the organic flocculation method when used with filters.     

Physician-patient relations--participation of patients with ureteral calculi in clinical decision making and level of anxiety

In a study examining the relationship between patient participation in clinical decision making and levels of anxiety, patients were offered a choice of treatment for ureteral calculus. 42 received information about 2 treatment options, ultrasound fragmentation of the stone through a ureteroscope and extracorporeal shock wave lithotripsy (ESWL), and were asked to choose the method that they preferred. 54 received treatment decided on by the physician without their participation in the decision making process. Anxiety was measured before meeting with the physician, immediately after the meeting and on hospitalization for treatment. The contribution of the patient's perception of participation in the decision-making process and level of education was also examined. There was a decrease in level of anxiety after meeting with the physician only among those who did not actually participate in the decision-making process (p < 0.05). There was no change in the level of anxiety among those offered choice of treatment. However, a decrease in anxiety was evident among patients who perceived that they had received information about their illness and its treatment (p < 0.01). This was not the case for patients who perceived themselves as participants in decision making unless they had a relatively high-level of education (p = 0.05).     

Nutritional evaluation of the fungus Phycomyces blakesleeanus as a protein source

The quality of the protein of the carotenogenic fungus Phycomyces blakesleeanus Burgeff, strain NRRL 1555 ( - ), was evaluated with rats and observed to have a protein efficiency ratio of 1.4. The limiting amino acids were tryptophan, sulphur-containing amino acids, lysine and isoleucine. Upon incorporation into diets containing 100 g kg⁻¹ protein the proportions of the above mentioned amino acids of the optimal recommended dietary allowances for growing rats were 33.0%, 57.4%, 74.5% and 87.2% respectively. Furthermore, the fungal protein was found to contain an excess of histidine about eight fold more than the recommended dietary allowance for growing rats. Some safety aspects were examined and, although the fungus was consumed in high dietary concentrations, 242 g kg⁻¹ of the diet, no pronounced toxicological effects were observed.     

Extended screening by PCR for seven cry-group genes from field-collected strains of Bacillus thuringiensis

An extended multiplex PCR method was established to rapidly identify and classify Bacillus thuringiensis strains containing cry (crystal protein) genes toxic to species of Lepidoptera, Coleoptera, and Diptera. The technique enriches current strategies and simplifies the initial stages of large-scale screening of cry genes by pinpointing isolates that contain specific genes or unique combinations of interest with potential insecticidal activities, thus facilitating subsequent toxicity assays. Five pairs of universal primers were designed to probe the highly conserved sequences and classify most (34 of about 60) genes known in the following groups: 20 cry1, 3 cry2, 4 cry3, 2 cry4, 2 cry7, and 3 cry8 genes. The DNA of each positive strain was probed with a set of specific primers designed for 20 of these genes and for cry11A. Twenty-two distinct cry-type profiles were identified from 126 field-collected B. thuringiensis strains. Several of them were found to be different from all published profiles. Some of the field-collected strains, but none of the 16 standard strains, were positive for cry2Ac. Three standard and 38 field-collected strains were positive by universal primers but negative by specific primers for all five known genes of cry7 and cry8. These field-collected strains seem to contain a new gene or genes that seem promising for biological control of insects and management of resistance.     

Optimum Setting for Proportional Controller

On the basis of four common criteria?integral square error (ISE), integral absolute error (IAE), time integral-square-error (ITSE), and time integral absolute error (ITAE)?optimal lines for typical sampled data servo drives for computer numerical control (CNC) are derived and approximated by simple equations. The objective is to provide the control engineer with a simple equation for the selection of the control parameters. A line of critical damping is also derived and simply approximated.