Colorectal cancer in Egyptian patients under 40 years of age.

Although colorectal cancer is not a common cancer in Egypt, the age distribution of the disease shows that a high proportion occurs in children and adults under 40 years of age. We reviewed the records of 1,608 colorectal cancer patients treated in 4 cancer hospitals in Egypt during a period of 3 to 10 years. The hospitals in which about 85% of all colorectal cancer cases in Egypt were seen included Egypt's 2 major cancer centers, The National Cancer Institute (NCI) in Cairo and Tanta Cancer Center (TCC) in the mid-Nile Delta region, and 2 major university hospitals, Assiut University in South Egypt and Ain Shams University in Cairo. Our review showed that patients younger than 40 years represented 35.6% of all patients in the 4 cancer hospitals, and that these rates were similar among the hospitals and for the years reviewed. The male-to-female ratio increased from 1.0 to 1.7 for the age groups ranging from 0-9 and 30-39 years, and increased from 1.0 to 1.5 for the age groups ranging from 40-49 to over 60 years. More than half of all the patients had rectal tumors, and about 90% of the cancers were adenocarcinomas; 30.6% of patients younger than 40 years, compared with 13.8% of older patients, had mucin-producing tumors. This study confirmed the occurrence of a high colorectal cancer rate in young Egyptians, and it opens the door to future epidemiologic studies to identify causes and risk factors of this disease pattern in Egypt.

Method modification for liquid chromatographic determination of thiamine, riboflavin, and pyridoxine in medical foods.

A reversed-phased ion pair liquid chromatographic method developed for the simultaneous determination of thiamine (B1), riboflavin (B2), and pyridoxine (B6) in perchloric acid extracts of infant formulas was modified to include medical foods. UV detection of B1 and B2 was replaced by fluorescence detection, which resulted in improved sensitivity and specificity. B1 was detected by fluorescence after conversion to thiochrome by a postcolumn reaction with sodium hydroxide and potassium ferricyanide. The method uses a mobile phase of water, acetonitrile, hexanesulfonic acid sodium salt, ammonium hydroxide, and phosphoric acid adjusted to pH 3.6. The column is a 300 x 3.9 mm Nova Pak C18. Limits of detection were 0.05 microgram/mL for B1 and B2 and 0.01 microgram/mL for B6 by fluorescence detection. The system reproducibility was evaluated by completing 10 repetitive determinations on a medical food that gave a coefficient of variation of 5.9, 6.0, and 10.7% for B1, B2, and B6, respectively. Mean recoveries (n = 10) were 111, 96.3, and 113% for B1, B2, and B6, respectively. The results compared favorably with those by AOAC Official Methods 942.23, 940.33, and 961.15 for B1, B2, and B6, respectively.

Liquid chromatographic analysis of niacin in fortified food products.

An ion exchange liquid chromatographic (LC) method using an anion exchange resin column was developed for the determination of niacin in fortified foods. Samples were extracted by autoclaving with H2SO4 (1 + 1). Florisil open column chromatography was used to remove interferences from the sample extracts. Niacin levels were quantitated by an LC system using a 250 x 4.1 mm Hamilton PRP-X100 column, a mobile phase of 2% glacial acetic acid in water, and UV detection at 254 nm. The limit of detection was 0.11 micrograms niacin/mL, and the standard curve was linear from 0.24 to 0.80 micrograms niacin/mL. The system reproducibility was evaluated by completing 10 repetitive analyses on an infant formula and a macaroni product, which gave an average CV of 2.7%. Mean recovery (+/- standard deviation) was 99.8 +/- 7.7 (n = 15). The results compared favorably with those by the AOAC microbiological method.

Ultrasonographic changes of the liver in Schistosoma haematobium infection.

Abdominal ultrasonographic examination was performed in 61 hospitalized patients with chronic liver diseases and 253 school children from a village endemic for Schistosoma haematobium and were compared with 142 urban children without exposure to Schistosoma. The prevalence of ultrasound-detectable hepatomegaly and splenomegaly and the degree of periportal fibrosis was compared between those with and without S. haematobium infection. Among 13 patients with biopsy-proven schistosomal hepatic fibrosis, three with coarse changes secondary to S. mansoni infection showed grade III periportal fibrosis, while 10 patients with fine schistosomal hepatic fibrosis due to S. haematobium had borderline (two) or grade I (eight) changes. Ultrasound evidence of periportal fibrosis was not detected in patients with hepatic cirrhosis, chronic active hepatitis, or fatty infiltration. However, three of 14 patients with chronic persistent hepatitis had grade I periportal fibrosis and two had borderline changes. The frequency of ultrasound-detected hepatomegaly and splenomegaly was greater among rural S. haematobium-infected children (35.2% and 22.4%, respectively) than among noninfected rural (21.1% and 13.3%) and urban (16.9% and 4.9%) children. Also, the frequency of grade I periportal fibrosis was significantly greater (P less than 0.01) in S. haematobium-infected children (22.4%) than in noninfected rural (11.7%) and urban (0.7%) children. No patients with S. haematobium infections, either in the hospital or the village, had grade II or III periportal fibrosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Application of a tri-enzyme extraction for total folate determination in foods.

A tri-enzyme digestion procedure using chicken pancreas conjugase, alpha-amylase, and Pronase was evaluated to determine its usefulness in the microbiological quantitation of total folate in foods. Folate values obtained by traditional conjugase digestion were compared to those obtained by the tri-enzyme method for 12 food products that represent diverse matrixes. The tri-enzyme treatment increased measurable folate from most foods when compared to levels found after conjugase digestion. Largest increases were noted for tuna fish (51%) and yogurt (33%) after tri-enzyme digestion. For the 12 foods, a mean increase of 19% in measurable folate was obtained with tri-enzyme treatment. The study shows that traditional conjugase treatment does not completely free folate from complex food matrixes before microbiological analysis. Further, as other investigations have suggested, current accepted methods for folate analysis may be underestimating folate levels in foods.

Hypoglycin A content in the aril, seeds, and husks of ackee fruit at various stages of ripeness.

Recently, hypoglycin A (HG-A), a natural toxin, was detected in canned ackee fruit. To determine the source of contamination, the HG-A content in the ackee fruit components (aril, seeds, and husks) at various stages of ripeness was determined by a method using an amino acid analyzer. HG-A concentrations in the unripe ackee fruit components were 939, 711, and 41.6 mg/100 g of seed, aril, and husk components, respectively. Analysis of the ripe fruit components showed that HG-A in the seed decreased to 269 mg/100 g and remained unchanged in the husk while the concentrations in the edible ripe aril decreased below the detection limit of 1.2 mg/100 g.

Ion-exchange chromatographic determination of hypoglycin A in canned ackee fruit.

An ion-exchange chromatographic method was developed to determine hypoglycin A (HG-A) levels in canned ackee fruit by using an amino acid analyzer. HG-A was extracted by homogenizing the sample in 80% alcohol. An isocratic buffer system, consisting of 30% sodium citrate buffer (pH 3.15) and 70% sodium chloride-sodium acetate buffer (pH 7.40) was used to obtain baseline separation between HG-A and the other amino acids. The system can detect HG-A levels as low as 4.8 micrograms/mL. HG-A levels in the edible portion of fruit in 6 cans ranged from 11.0 to 66.5 mg HG-A/can. Recoveries by standard addition averaged 102.5%.

Vitamin A and vitamin E content of infant formulas produced in the United States.

Vitamin A (vitamin A palmitate) and vitamin E (alpha-tocopheryl acetate) levels were determined in 77 samples of fortified infant formulas manufactured by 4 firms in the United States from 1981 to 1983 and were compared by formulation base (soy, milk) and manufacturing firm. For vitamin A and vitamin E, the mean values (IU/100 kcal) were 454 +/- 95 (range 248-614) and 2.0 +/- 0.7 (range 1.1-5.0), respectively. No significant differences (alpha = 0.05) were found in levels (IU/100 kcal) of vitamin A and vitamin E between milk- and soy-based formulas. When the mean vitamin A and vitamin E levels of formulas produced by the various firms were compared on an IU/100 kcal or percent of label declaration basis, significant differences (alpha = 0.05) were found among firms. Mean vitamin A levels for the various products compared to label declarations ranged from 126% of declared for the ready-to-use formulas to 139% of declared for the powders. Mean vitamin E levels ranged from 97% of declared for ready-to-use formulas to 118% of declared for concentrates. Except for one sample that contained 248 IU vitamin A/100 kcal, the formulas met the requirements of the 1980 Infant Formula Act.

Comparison of manual and benzenesulfonyl chloride-semiautomated thiochrome methods for determination of thiamine in foods.

A semiautomated procedure was used to measure the fluorescence of sample extracts before and after the addition of benzenesulfonyl chloride (BSC). Addition of BSC inhibited thiochrome formation and provided a more representative blank based on the fluorescence of all the reactants except thiochrome. Thiamine standard was added to each sample extract so that thiamine concentration could be calculated after correcting for sample matrix effects on thiochrome fluorescence. Twenty food products were analyzed using this method, and the results were compared with those obtained using the manual AOAC method. The mean percent recoveries and standard deviations were 100.2 +/- 5.3 and 101.1 +/- 10.1 for the BSC-semiautomated and the AOAC manual methods, respectively. Replicate analyses using the BSC method gave an average coefficient of variation of 2.8%. Linear regression analysis showed that the BSC method gave higher values, with a mean increase of 14.8%, than those obtained using the manual method. Sixty-four percent of this difference was due to elimination of the column purification step and 36% was due to correcting for sample matrix effects on thiochrome and blank fluorescence. The BSC method provides a rapid, accurate, and reproducible method for thiamine assay in different food products, especially for those foods with low thiamine levels.

Marrow cell kinetics in patients treated with methotrexate and citrovorum factor.

Methotrexate (MTX) was administered by continual intravenous infusion for 24 hours in doses ranging from 200-800 mg/m2 to 16 patients who had metastatic cancers and normal bone marrows and 11 patients with acute leukemia. Citrovorum factor (CF) was administered every 6 hours for 12-15 doses beginning 36 hours after the start of the MTX infusion. Plasma and urine were collected to measure MTX concentration. Daily bone marrow aspirates were obtained for measuring intracellular MTX concentration, labelling index (LI), mitotic index (MI), grain count distribution, cellular DNA distribution by flow cytometry (FCM), and marrow morphology. The plasma MTX concentration proved to be a function of dose and creatinine clearance. There was a positive correlation between the creatinine clearance and MTX clearance. The intracellular MTX concentration correlated highly with the plasma concentration. The LI, grain count, and proportion of cells in S phase increased on days 2 and 3. The magnitude of the changes on days 2 and 3 was dose related. The MI fell on day 2 and recovered by day 4. Transient megaloblastic changes occurred. The cell cycle perturbations in leukemic marrow were less pronounced than those in normal marrows. These observations are consistent with a transient, dose related, S phase delay.