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The reduction of sulfur content in gasoline and diesel fuel is a great environmental concern to reduce the motor vehicle emissions. Oxidative desulfurization using acetonitrile biphasic system has received much attention in recent years. The oxidative desulfurization can be oxidized the unreactive sulfur contents in the hydrodesulfurization and removed effectively. For the oxidative desulfurization process design and development, liquid–liquid equilibria (LLE) for acetonitrile biphasic systems are needed as fundamental information. In our previous work, LLE for acetonitrile + n-octane and + n-decane systems have been reported. In this work, therefore, LLE for acetonitrile + n-hexadecane system was measured. Furthermore, NRTL equation was applied to correlate the LLE for these three acetonitrile + n-alkane systems.

A newly developed laser light scattering technique was tested for the determination of cloud-point curves in polystyrene+cyclohexane and in polystyrene+methyl acetate systems at moderate pressures. The solubility data were determined for molecular weights of polystyrene of M ×10 −4 =9.0 and 19.0 for the cyclohexane system, and of M ×10 −4 =70.6 for the methyl acetate system at temperatures up to upper critical solution temperature. The experimentally determined cloud points were satisfactory correlated by Flory type models.

Flow cytometric analysis of cell cycle fractions and DNA ploidy was performed on 39 biopsy specimens of oral leukoplakia. The aneuploidy rate of these leukoplakias was 9/39 (23.1%) and the mean DNA index of the aneuploid lesions was 1.34. The aneuploidy rate was significantly higher in severely dysplastic lesions (8/17) than in mildly dysplastic (1/15, P

Weakly acidic cation-exchange resins in H + form, partially neutralized with H 2 N(CH 2 ) n N + Me 3 OH − ( n = 2–5), have been shown to catalyze the Knoevenagel condensation. The efficiency of catalysis depends on the aminoalkyl chain length and extent of neutralization.

We investigated a relationship between sialographic findings of parotid glands and histopathologic changes of labial glands, in relation to Sjogren's syndrome. We examined 107 patients, suspected to have Sjogren's syndrome because of dry mouth and dry eyes, in whom no other autoimmune diseases were diagnosed. Parotid sialography identified 37 patients with punctate, globular, cavitary, or destructive sialectasia (S-positive group). These sialographic findings were not seen in the other 70 patients (S-negative group). Among these patients, 54 demonstrated periductal lymphocytic infiltration in the labial glands (H-positive group), whereas the other 53 patients did not demonstrate this histologic finding (H-negative group). Significant differences in stimulated parotid salivary flow rate and incidence of keratoconjunctivitis sicca were observed between patients in the S-positive and the S-negative groups. Differences in the salivary flow rate and the incidence of keratoconjunctivitis sicca were also seen between patients in the H-positive and the H-negative groups, although the differences were not statistically significant. The rate of incidence of serum rheumatoid factor, anti-SS-A, and anti-SS-B antibodies were significantly higher in the S-positive and the H-positive groups than in their negative counterparts.

On the basis of a methylation study of N6-benzyl-9-methyl-8-oxoadenine (8), the first synthesis of caissarone hydrochloride (1) has been achieved via a two-step route including methylation of the N6-methyl analogue (3).

For the sensitive detection of free sugars and oligosaccharides, the use of their pyridylamino derivatives has now found general acceptance. To remove excess 2-aminopyridine from this derivative in a reaction mixture, gel filtration and ion-exchange chromatography were conducted. It was found in the present study that contaminated 2-aminopyridine could be selectively removed from the reaction mixture by adjusting the pH with saturated sodium bicarbonate at above 8.5 followed by extraction with benzene. By using this method, fewer purification steps and less time are required, with minimum loss of pyridylamino sugar derivatives.

A single injection of mice with maleic anhydride divinyl ether (MVE-2) resulted in significantly augmented natural killer (NK) activity. However, multiple injections with MVE-2 led to a hyporesponsive to boosting of NK activity. Stimulation of prostaglandin E secretion of induction of suppressor macrophages (Mo) or lymphocytes were shown not to be responsible for the depressed NK cell responses. Rather the hyporesponsiveness to NK boosting was associated with a decreased number of large granular lymphocytes (LGLs). Percoll discontinuousdensity-gradient studies showed that the augmented NK activity of spleen cells after a single injection with MVE-2 was associated with an increase in the percentage of LGLs in the lowerdensity fractions (Fraction 1 and 2). In contrast, the NK activity and percentage of LGLs in the lower-density fractions were markedly decreased after multiple injections with MVE-2. Polyinosinic: polycytidylic acid stabilized with poly( l -lysine) in carboxymethylcellulose, another BRM capable of augmenting NK activity, was able to substantially augment NK activity in mice hyporesponsive to MVE-2 and this was accompanied by an increase in the percentage of LGLs in the lower-density Percoll fractions.

The first synthesis of the antitumor antibiotic guanine 7-oxide (VI) has been achieved via a 4-step route starting from phenacyl bromide (I) and the nitropyrimidone III and proceeding through the intermediates IVe and Ve.