Screening for diabetic retinopathy: the utility of nonmydriatic retinal photography in Egyptian adults

BACKGROUND AND OBJECTIVE: Drug resistance has become a major cause of treatment failure in patients with acute leukemia. P-glycoprotein (Pgp), which is associated with the multidrug resistance (MDR) phenotype, has been reported to be an important predictor of treatment outcome. The aim of this study was to analyze the value of Pgp expression in bone marrow or peripheral blood as a predictor of the response to remission induction chemotherapy as well as the duration of remission in patients with de novo acute myeloid leukemia (AML). DESIGN AND METHODS: We examined the expression of Pgp in 82 patients with de novo AML using an immunocytochemical assay with the C219 monoclonal antibody. RESULTS: Twenty-seven of the 82 patients (33%) were C219-positive in from 1% to 100% of their cells. Thirteen cases (16%) showed a positive reaction in more than 50% of the leukemic cells. Only hyperleukocytosis was significantly associated with higher expression of Pgp. Although 8 of the 13 cases (62%) with more than 50% of cells having Pgp expression were CD34-positive, this association was not statistically significant. A univariate analysis of resistance to induction therapy showed a significantly higher resistance rate in patients with increased Pgp expression (P = 0.01) as well as in those patients with decreased reactivity to myeloperoxidase. The multivariate analysis revealed the independent prognostic value of Pgp expression. C219 reactivity did not have an influence on remission duration. INTERPRETATION AND CONCLUSIONS: Our data indicate that P-glycoprotein expression is a reliable marker of resistance to induction treatment in patients with de novo AML.     

Correlation of vapor-liquid equilibria for binary mixtures with free energy-based equation of state mixing rules: Carbon dioxide with alcohols, hydrocarbons, and several other compounds

The correlation of vapor-liquid equilibrium data for high-pressure carbon dioxide systems is of interest in a number of industrial applications, including supercritical extraction. Here, we consider the correlation of data for 12 binary systems of carbon dioxide separately with alcohols, with hydrocarbons, and with acetone, benzene, and water. The Wong-Sandler (W-S) and modified Huron — Vidal first order (MHV1) free energy-based equation of state mixing rules (the W-S and MHV1 models) were used in the calculations. Both combined equation of state+free energy models generally resulted in good correlations of the experimental data over wide ranges of temperature and pressure with temperature — independent parameters. However, for the carbon dioxide+water system, the W-S model produced an 11% average absolute deviation in pressure, while no parameter that resulted in an AAD in pressure of less than 20% could be found for the MHV1 model.     

Root growth and phosphorus and potassium uptake by two corn genotypes in the field

In a field study P and K uptake by two corn (Zea mays L.) genotypes which differed in root growth was investigated. The effect of differences in root growth on P and K uptake was assessed using a mechanistic-mathematical model which describes nutrient uptake by growing plant roots in soil. Nitrogen was applied at 0 and 227 kg ha^–1 to Pioneer 3732 and B73xMo17 corn grown on Raub silt loam (fine-silty, mixed, mesic Aquic Argiudoll) and at 227 kg N ha^–1 to these two genotypes on Chalmers silt loam (finesilty, mixed, mesic, Typic Haplaquoll). Root growth and P and K uptake by the two corn genotypes was measured 31, 47, 75 and 91 d after planting on the Raub and 31, 47, 61 and 75 d after planting on the Chalmers soil.Root growth and P and K uptake by B73xMo17 was greater than that of Pioneer 3732 on N-fertilized Raub soil. On Chalmers soil the difference in root growth between the two genotypes resulted in an increase in K but not P uptake. The higher soil P level of the Chalmers appears to have offset possible differences in P uptake due to root size. There were no differences between the two genotypes in either the percentage of roots with root hairs, or the density or length of root hairs. Phosphorus and K uptake calculated with the simulation models for both corn genotypes on both soils over each of three growth periods agreed with observed P (Y = 0.68X + 1.71; r = 0.944^**) and K (Y = 0.88X + 15.52; r = 0.928^**) uptake. Differences in P and K uptake between B73xMo17 and Pioneer 3732 resulted primarily from the difference in root growth in the topsoil. A high correlation was found between root surface area and P (r = 0.893^**) and K (r = 0.928^**) uptake by both corn genotypes on both the soils.Journal paper No. 10,316 Purdue Univ. Agric. Exp. Stn., W. Lafayette, In 47906. Contribution from the Dep. of Agron. This paper was supported in part by a grant from the Tennessee Valley Authority.     

Role of intimin and bundle-forming pili in enteropathogenic Escherichia coli adhesion to pediatric intestinal tissue in vitro

Attaching and effacing (A/E) lesion formation is central to enteropathogenic Escherichia coli (EPEC) pathogenesis. In vitro experiments with human epithelial cell lines have implicated virulence plasmid-encoded bundle-forming pili (BFP) in initial binding and intimin in intimate attachment and A/E lesion formation. This study investigated the role of BFP and intimin in EPEC interactions with pediatric small intestinal biopsy tissue in in vitro organ culture. Organ culture infections (2 to 8 h) were performed with E2348/69 (a wild-type EPEC O127:H6 clinical isolate) and E2348/69 derivatives including CVD206 (eae deficient), CVD206(pCVD438) (eae-complemented CVD206), CVD206(pCVD438/01) (expressing intimin, which is nonfunctional due to a single amino acid substitution), JPN15 (spontaneous EPEC adherence factor virulence plasmid-cured E2348/69), and 31-6-1(1) (E2348/69 with a TnphoA insertion inactivation mutation in the virulence plasmid-encoded bfpA gene). Scanning and transmission electron microscopy revealed that after 8 h E2348/69 and CVD206 (pCVD438) (both Int+ BFP+) adhered to all specimens, causing A/E lesions with surrounding microvillous elongation. JPN15 and 31-6-1(1) (both Int+ BFP-) adhered and caused A/E lesions although bacteria adhered in "flat," two-dimensional groups. CVD206 and CVD206(pCVD438/01) (both Int- BFP+) did not adhere to any sample, and no pathological tissue changes were seen. Thus, in human intestinal organ culture, BFP do not appear to be involved in the initial stages of EPEC nonintimate adhesion but are implicated in the formation of complex, three-dimensional colonies via bacterium-bacterium interactions. Intimin appears to play an essential role in establishing colonization of EPEC on pediatric small intestinal tissue.     

Spinal neurilemmomas and neurofibromas: central dot sign in postgadolinium MRI

The MR studies of three histologically proven spinal neurilemmomas and neurofibromas were reviewed retrospectively. There were two benign neurilemmomas (schwannomas) and one neurofibroma. The common characteristic of these cases was a central low intensity focus ("dot") seen on postcontrast T1-weighted imaging. The low intensity foci corresponded histologically to a congeries of changes including edema, microcysts, foam cells, hyalinization of blood vessels, old hemorrhage, and dystrophic calcification.     

Accessory artificial circulation in complex treatment of experimental acute toxic pulmonary edema

In experiments on 50 dogs with toxic acute edema of the lung, induced with intravenous injection of 0.1% silver nitrate, the authors have studied the efficacy of accessory artificial circulation and "conservative" therapy. During the perfusion a discharge of the right portions, adequate extracorporeal gas metabolism, normalization of blood gas and acid-base balance were noted; an intensity of pulmonary edema is descreased. An intensive therapy for pulmonary edema was found to be more effective in association of "conservative" treatment with venoarterial perfusion and blood oxygenation.     

Nitrous oxide "analgesia": resemblance to opiate action

Nitrous oxide produced a dose-related "analgesia" in mice (median effective dose, 55 percent). The analgesia was evaluated by means of a phenylquinone writhing test. Narcotic antagonists or chronic morphinization reduced nitrous oxide analgesia. Either nitrous oxide releases an endogenous analgesic or narcotic antagonists have analgesic antagonist properties heretofore unappreciated.