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Serum lipid-bound sialic acid (LSA) was measured with a recently described procedure in 108 healthy subjects and in 138 patients with a variety of solid tumors and hematologic malignancies. At the time of serum sampling, 128 patients had active disease and 10 patients had no evidence of disease. LSA was elevated in 104 of 128 (81.2%) patients with active disease, while carcinoembryonic antigen, analyzed in 74, was elevated only in 21 (28.4%) (P < 0.05). Sensitivity of the serum LSA test ranged from 66% for breast and gastrointestinal cancer to 92% for lung cancer. In patients with lung cancer, ovarian cancer or Hodgkin's disease, LSA was correlated with the extent of disease and it also proved to be useful in following the course of disease. Our preliminary data indicate that this test can be used as a monitor of tumor burden.

The secretion of the parotoid glands of six species of toads of the genus Bufo has been analysed with circular chromatograpy. From the resulting bands a ≪dissimilarity matrix≫ was constructed. The numerical data, derived from a computer program, yielded a den drogram of the evolution of the analysed secretion that fits well with dendrograms obtained for the corresponding species in pre vious studies using various biological parameters. The easy‐to‐perform chromatographic technique described in this paper could have various biological applications.

Eleutherin and eleutherol extracted from bulbs of Eleutherine bulbosa (Miller) Urb. (Iridaceae), collected in the Amazonian jungle and grown in Italy, were tested for biological properties. The extraction procedure and the results of antibacterial, cytotoxicity, and pharmacological assays are reported. Eleutherin has a weak and transient effect of decreasing the prothrombin time (in vivo in rats) and a weak antibacterial activity on Bacillus subtilis (in vitro).

Le varie metodiche per la rivelazione citochimica delle perossidasi presentano alcuni inconvenienti, quali la scarsa stabilita del reattivo alla benzidina e soprattutto la formazione, a livello dei granuli stessi, di lunghi cristalli di blu di benzidina; esse inoltre trascurano il controllo del pH e della temperatura che, per una reazione enzimatica, sono fattori molto importanti. Gli AA., nella metodica qui descritta, propongono un reattivo alla benzidina discretamente stabile ed eseguono la reazione enzimatica a 37 °C ed in ambiente tamponato per evitare la formazione di precipitati cristallini ed ottenere cosi dei chiari quadri morfologici.

Some methodological problems in clinical enzymology, including instability of enzymes in the incubation mixture and requirements for optimal reaction conditions, are highlighted. The importance of a knowledge of fundamental enzyme biochemistry and physiology as the basis for their diagnostic application is stressed, and the different behaviour of some hepatic enzymes—namely, GOT, GPT, γ-GT, and OCT, in various pathological conditions is traced back to their characteristic biochemical and physiological properties. In the field of urinary enzymes a knowledge of the ideal requirements for the enzyme investigation of the various renal functions and of the properties of potentially valuable enzymes permits a critical selection of the really useful ones.

E stata studiata l’attivita α-glucosidasica nel siero di soggetti normali, di pazienti con anuria acuta e di altri pazienti con lesioni renali primitive o secondarie. In tutti i casi con anuria acuta, l’enzima e presente nel sangue, talora a livelli elevati, mentre negli altri casi studiati esso e assente o presente a bassi livelli. E stata esclusa la possibilite che l’assenza dell’attivita enzimatica sia dovuta alia presenza nel siero di inibitori. La curva di pH dell’enzima ematico e risultata sovrapponibile a quella dell’enzima urinario. Vengono discussi l’origine renale dell’enzima sierico e il meccanismo del suo passaggio nel sangue.

L’escrezione con l’urina di α-glucosidasi, contenuta nelle cellule tubulari renali, e un’espressione dell’intensita della lisi di tali elementi. La determinazione quantitativa di tale enzima e un mezzo molto sensibile per rivelare alterazioni litiche. Un confronto tra enzimuria e tipo di proteinuria ha dimostrato che non vi e una correlazione costante tra entita della enzimuria e quadro di proteinuria tubulare. I due indici sono quindi espressione di due diversi tipi di alterazione del tubulo, che possono o meno sovrapporsi ed hanno quindi significato complementare. In particolare, la determinazione dell’α-glucosidasi, per la sua elevata sensibilita, puo evidenziare lesioni tubulari, anche quando non sono sufficientemente intense per determinare il danno funzionale di alterato riassorbimento, espresso dal quadro di proteinuria tubulare.

A crystalline substance with marked antimitotic activity on several biological systems (mitoses of ascites S 180, of the megaloblasts of chick embryo, of the tips of wheat radicles) has been isolated from the bulbs of several varieties of Narcissus and named Narciclasine. After reference to the tests that led to its discovery and isolation and to the work of others in the same field, the method of isolation is described together with the physical and chemical properties of the substance (identification, chromatographic behavior, UV, IR and fluorescence). The structural formula, established on the basis of work reported elsewhere, is given.

Intraperitoneally or subcutaneously injected narciclasine exerts an inhibiting activity on the mitoses of ascites Sarcoma 180. According to the dosage mitoses are blocked at metaphase or at preprophase. For the highest doses a mitoclasic effect is also present. Mitoses of duodenal mucosa and of bone marrow were much less affected by narciclasine.

Ornithine carbamyl transferase (EC 2.1.3.3) is evaluated through the determination of the citrulline produced, by the diacetylmonoxime-antipyrine reaction, while the urea present is destroyed by urease. The optimal conditions for the enzymatic reaction have been investigated. The relative concentrations of carbamyl phosphate and ornithine, the type of buffer and pH have been arranged to reach a maximum reaction rate without production of non-enzymatic chromogens. The chromogenic reaction has been modified to allow it to be performed without deproteinization. Micro-amounts of serum are employed (25 μl). Kinetic results with the new procedure are presented. The range of normal values has been determined in a healthy and in a hospital population.

Pepsinogens, proteolytic enzymes produced by peptic cells of the stomach and discharged into the gastric lumen as well as into the blood have been divided into two groups: PG-I, originating from chief cells, and PG-II, mainly from antrum peptic cells. Both total serum pepsinogen (s-Pg) and PG-I have been separately reported as being significantly increased in gastric (GU) and duodenal ulcer (DU) patients and related to maximal acid output. In order to ascertain the relationship between s-Pg measured by means of the colorimetric Uete method, and PG-I determined by RIA method, these were assayed in 72 control subjects, 35 GU and 95 DU patients. s-Pg was found to be significantly increased both in GU and DU patients in comparison with control subjects. Likewise PG-I was significantly enhanced in GU and DU patients as compared with controls. A significant direct correlation between s-Pg and PG-I was found in all the subjects studied (r = 0.732).

Urea can be directly determined in serum or plasma by reaction with diacetylmonoxime—antipyrine: 5 µl of the sample is mixed with 5 ml of the chromogenic reagent, and the mixture is boiled 15 min, cooled, and read at 460 nm. The color is stable for 30 min in the light. The reagent is composed of (a) 0.4 g of antipyrine per 100 ml of H2SO4 (20 ml/100 ml), containing 5 mg of ferric sulfate per 100 ml: 1 (or 2) volume(s), and (b) 0.5 g of diacetylmonoxime per 100 ml of acetic acid (5 ml/100 ml): 1 volume.

Buzzati-Traverso and Rechnitzer proposed a simple chromatographic technique for taxonomic studies on fishes1; Buzzati-Traverso applied it also to genetic studies on Drosophila 2. In the original technique, the tissues were simply squeezed on filter paper, dried and chromatographed. The method was used almost as such by some authors for taxonomic studies on land snails3, mosquitoes4, and for investigating several mouse and tumour tissues5. The present method, although starting from the same principle, was developed in a rather different manner. It does not utilize fresh tissues, but tissues which have been dried and powdered. By this means it is possible to use an accurately known amount of tissue, independently of its water content, and to extract completely the free metabolites from the broken cells; furthermore, the samples used may be larger, thus allowing the detection of metabolites which may be present in amounts too small to be detected by the use of small pieces of tissue.

Heparin, when added in vitro at rather high concentrations (400--1000 kilounits/L) as an anticoagulant, interferes with albumin determination by bromcresol green by forming an insoluble precipitate with this dye. The interference is much less with bromcresol purple. It can be abolished by addition of hexadimethrine bromide.

A method is described for determining glucose in 25 µl of plasma. o-Toluidine is used in weak acetic acid solution. Addition of the emulsifier "Cremophor" obviates the need for deproteinization. The reaction is complete after 15 min at 100°C, and the color is stable for longer than 24 h. The blank is almost colorless. The reagent is stable, colorless, not viscous, and convenient to handle.