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A conjunctival cyst is a thin-walled sac or vesicle that contains fluid. This vesicle may develop either on or under the conjunctiva. It develops due to variety of causes such as infection, inflammation, retention cyst and rarely drug induced. The authors aimed to report a case of conjuctival cyst in a 34-year-old male following instillation of anti-allergic topical drugs for over period of one year. Conjuctival cyst developing due to chronic use of anti-allergic topical drugs containing preservatives is one of the complications associated with it. Presence of a preservative in an ocular medication has often been considered in damaging the epithelium. Inclusion of a preservative is equally necessary, especially in multiple-drug therapy in order to protect against dangerous organisms accidentally gaining access during instillation. Benzalkonium chloride (BAK), chlorobutanol, chlorhexidine acetate (CHA) and phenylmercuric nitrate or acetate are some commonly used preservatives in eye drops.

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Preclinical data suggests that the action of fluoropyrimidines may be enhanced by the addition of hydroxyurea. We developed a phase I trial to determine the maximum tolerated dose and pharmacokinetics of i.v. hydroxyurea (HU) in combination with i.p. 5-fluoro-2'-deoxyuridine (FUdR) and leucovorin (LV). Eligible patients had metastatic carcinoma confined mostly to the peritoneal cavity, and adequate hepatic, renal and bone marrow function. Patients were treated with a fixed dose of FUdR (3 g) and LV (640 mg) administered on days 1--3. HU was administered as a 72-h infusion starting simultaneously with i.p. therapy on day 1. The following dose levels were studied: 2.0, 2.5, 3.0 and 3.6 g/m(2)/day. Pharmacokinetics were studied in blood and peritoneal fluid. Twenty-eight patients were accrued. Steady-state plasma and peritoneal fluid HU levels increased with increasing dose, and steady state was achieved within 12 h of continuous dosing. The steady-state HU plasma:peritoneal fluid concentration ratio ranged from 1.06 x 10(3) to 1.25 x 10(3) and the plasma HU clearance ranged from 4.63 to 5.81 l/h/m(2). Peritoneal fluid AUC = 137,639 +/- 43,914 microg/ml x min, t(1/2) = 100.9 +/- 56.4 min and Cl = 25.29 +/- 10.88 ml/min. Neutropenia represented the dose-limiting toxicity. We conclude that i.p. FUdR and LV in combination with i.v. HU is well tolerated. The addition of systemic HU increased the incidence of myelosuppression.

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Rate constants have been determined for hydrolysis of the acetate, glutarate, and phthalate monoesters of 2-hydroxy-1,10-phenanthroline in water at 30 degrees C and &mgr; = 0.1 M with KCl. The hydrolysis reactions of the esters are hydroxide ion catalyzed at pH > 9. The phthalate and glutarate monoesters have in addition pH-independent reactions from pH 5.5 to 9 that involve intramolecular participation by the neighboring carboxylate anion. The pH-independent reaction of the glutarate monoester is approximately 5-fold faster than that of the phthalate monoester. The plots of log k(obsd) vs pH for hydrolysis of the carboxyl substituted esters are bell shaped at pH < 5, which indicates a rapid reaction of the zwitterionic species (carboxyl anion and protonated phenanthroline nitrogen). The divalent metal ions, Cu(2+), Ni(2+), Zn(2+), and Co(2+), complex strongly with the esters; saturation occurs at metal ion concentrations less than 0.01 M. The 1:1 metal ion complexes have greatly enhanced rates of hydrolysis; the second-order rate constants for the OH(-) reactions are increased by factors of 10(5) to 10(8) by the metal ion. The pH-rate constant profiles for the phthalate and glutarate ester metal ion complexes have a sigmoidal region below pH 6 that can be attributed to a metal ion-promoted carboxylate anion nucleophilic reaction. The carboxyl group reactions are enhanced 10(2) - to 10(3) -fold by the metal ions, which allows the neighboring group reaction to be competitive with the favorable metal ion-promoted OH(-) reaction at pH < 6, but not at pH > 6. The half-lives of the pH-independent neighboring carboxyl group reactions of the Cu(II) complexes at 30 degrees C are approximately l2 s. The other metal ion complexes are only slightly less reactive (half-lives vary from 2.5 to 40 s). These are the most rapid neighboring carboxyl group reactions that have been observed in ester hydrolysis. Copyright 2000 Academic Press.

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A sensitive method has been developed for the determination of hydroxyurea in plasma and peritoneal fluid using reversed-phase high-performance liquid chromatography (HPLC) with electrochemical detection. Plasma or peritoneal fluid samples were treated with acetonitrile to precipitate proteins then injected to the HPLC. A C18 analytical column was used to separate hydroxyurea from interfering substances in the biological matrix. The mobile phase, consisting of 0.2 M sodium perchlorate-methanol (95:5, v/v) adjusted to pH 5.0, was delivered isocratically at a flow-rate of 1 ml/min and hydroxyurea was detected using a glassy-carbon electrode operating at an applied potential of +800 mV. Hydroxyurea eluted with a retention time of 3 min. The cycle time for analysis is short and the assay precision is acceptable (C.V. plasma=1.4-3.9%. C.V. peritoneal fluid=2.1-9.7%). The method has been validated and is linear from 25 to 400 ng/ml in plasma and 5 to 30 ng/ml in peritoneal fluid. The method has been shown to be applicable for pharmacokinetic studies.

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A case of leiomyoma of Meckel's diverticulum associated with a carcinoma of the descending colon, presenting with intestinal obstruction, is described. Only two cases of smooth muscle tumors of the small intestine associated with carcinoma of the large bowel have been described so far, and ours is probably the first case of its kind to be reported. The importance of angiography and a through intraoperative exploration is stressed.

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Four cases of torsion of the fallopian tube following sterilization are reported. This is a rare complication that may occur two to eight years after tubal ligation. It is more likely to occur after Pomeroy's, Irving's or the Viennese school technique of sterilization, in which the free distal segment of the fallopian tube is suspended by a narrow mesentery. Hydrosalpinx, which is common after sterilization, seems to predispose to torsion.

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