A screening method was established to detect inhibitors of the biosynthetic pathways of aromatic amino acids and para-aminobenzoic acid, the precursor of folic acid, using an agar plate diffusion assay modified as an antagonism test. By this screening method, a family of three novel polycyclic polyketides named as abyssomicins was ...

A first derivative spectrometric method has been developed for the determination of the para-aminobenzoic acid (PABA), a related substance and degradation product of the local anesthetic procaine hydrochloride (PH). The wavelength selected for the determination of para-aminobenzoic acid in the presence of procaine was 290 nm. At this wavelength the ...

Using the crystal basis model of the genetic code, a set of relations between the physical-chemical properties of the amino acids are derived and compared with the experimental data. A prediction for the not yet measured thermodynamical parameters of three amino acids is done.

An investigation of the triterpenoid fraction of zucchini seeds afforded two novel multiflorane p-aminobenzoates, identified as 7-epi zucchini factor A and debenzoyl zucchini factor B. Multiflorane p-aminobenzoates could not be detected in zucchini sprouts, which contained bryonolic acid as the only multiflorane constituent. No compound of this type could be ...

Following exposure of rats to the arylamine carcinogen 2-aminofluorene, DNA-carcinogen adducts were found in the target tissues of the liver and bladder, and also in circulating leucocytes. This work investigated how paeonol affects arylamine (2-aminofluorene and p-aminobenzoic acid) acetylations in rat leucocytes. Evidence is presented showing that rat mononuclear leucocytes ...

The qualities of para-aminobenzoic acid (PABA) are discussed and an account is given of how it came to be the favourite sunscreen of the post World War II era. Slowly, however, dermatologists became aware that it was a fairly common sensitizer and that it tended to cross-sensitize with compounds of ...

Lichen encrustations from Diploschistes scruposus involved in the biodeterioration of the 13th Century Convento de la Peregrina in Sahagún Spain, have been analyzed using Raman spectroscopy. The vibrational spectra are characteristic of calcium oxalate monohydrate, beta-carotene, chlorophyll, and para-depside phenolic acids such as atranorin, lecanoric acid, and diploschistesic acid. The ...

OBJECTIVE: This study investigated the biosynthesis of P-aminobenzoic acid by Streptococcus sanguis and the role of P-aminobenzoic acid in the interaction between Streptococcus sanguis and Streptococcus mutans. METHODS: A reversed-phase high-performance liquid chromatographic technique was used to analyze the P-aminobenzoic acid synthesized by Streptococcus sanguis in an anaerobic atmosphere. RESULTS: ...

Equilibrium acidities (pK(HA)) of six P-(para-substituted benzyl)triphenylphosphonium (p-GC(6)H(4)CH(2)PPh(3)(+)) cations, P-allyltriphenylphosphonium cation, P-cinnamyltriphenylphosphonium cation, and As-(p-cyanobenzyl)triphenylarsonium cation, together with the oxidation potentials [E(ox)(A(-))] of their conjugate anions (ylides) have been measured in dimethyl sulfoxide (DMSO) solution. The acidifying effects of the alpha-triphenylphosphonium groups on the acidic C-H bonds in toluene and ...

Scarring is a well-known side-effect of cutaneous laser treatment and exposure to solar ultraviolet radiation is suspected to increase scar formation. We investigated how wounds and scarring were modified by interfering in the laser-induced inflammation using ultraviolet radiation and para-aminobenzoic acid. A copper vapour laser operating at 578 nm was ...

Nitrogenase activity (C2H2 reduction) was demonstrated in seedlings of wheat roots bearing para-nodules induced by 2,4-dichlorophenoxyacetic acid (2,4-D) and inoculated with Azospirillum brasilense. Increased nitrogenase activity was observed in inoculated para-nodulated seedlings as compared to inoculated roots not treated by 2,4-D under the conditions of assay used. 2,4-D had no ...

Spectrofluorimetry was investigated as an alternative to HPLC for determining p-aminobenzoic acid and p-aminosalicylic acid in the N-benzoyl-L-tyrosyl-p-aminobenzoic acid/p-aminosalicylic acid test of pancreatic exocrine function. Urine specimens were hydrolysed for 30 min in 4 M NaOH at 100 degrees C. The fluorescence of p-aminobenzoic acid was measured in dimethyl sulphoxide ...

The in vitro antimycobacterial activities of sulfasalazine and its split products, mesalazine (5-aminosalicylic acid) and sulfapyridine, against 170 mycobacterial strains belonging to 17 species were compared with those of diaminodiphenylsulfone, sulfadimethoxine, olsalazine, and para-aminosalicyclic acid. Only para-aminosalicylic acid showed consistent activity against Mycobacterium tuberculosis. These data suggest that the principle ...

48 patients with allergic contact dermatitis from Frullania were patch tested with a lichen mix, compositae and lichen acids. 27 were sensitive to Frullania and lichens. Parmelia caperata and Parmelia reticulata were positive in all, and in a descending order of positivity: Pseudovernia furfuracea, Evernia prunastri, Usnea spp, Ramalina lusitanica. ...

The concept of the orienting reflex is discussed from the historical perspective. The following conclusions are proposed: (1) in accordance with the spirit of Pavlov's concept the orienting reflex is a response to a stimulus unexpected in a given situation; (2) the reflex consists of targeting, arousal and perceptual components; ...

Michaelis-Menten constants for two in vivo monomorphically N-acetylated substrates, p-aminobenzoic acid and p-aminosalicylic acid, and two in vivo polymorphically N-acetylated substrates, sulfamethazine and procainamide, were determined with an improved assay procedure using liver N-acetyltransferase from rapid and slow acetylator rabbit. The slow rabbit liver isozyme proves to be a Vmax ...

We describe a new approach to the bentiromide test of exocrine pancreatic function, p-Aminosalicylic acid (PAS), a compound closely related to the bentiromide fragment p-aminobenzoic acid (PABA), is used as a marker of the pharmacokinetic behavior of PABA to derive a PABA excretion index. This index is identical to that ...

Madecassol is an extract of Centella asiatica, a member of the Umbelliferae family. It contains madecassic acid, asiatic acid and asiaticoside. It has been used as a wound healing agent and for the prevention of cicatrization. We report contact dermatitis due to Madecassol and a control study with its individual ...

Para-aminobenzoic acid (PABA) and some of its esters, such as amyl para-dimethylaminobenzoate, ethyl 4-bis(hydroxypropyl)aminobenzoate, 2-ethylhexyl para-dimethylaminobenzoate and glyceryl para-aminobenzoate are used as sunscreen agents. Methods for separating PABA and the 5 mentioned PABA esters by thin layer chromatography and high pressure liquid chromatography (HPLC) are presented. Contamination with PABA and ...

The short lived (t 1/2 7.2 h) alpha-particle emitting halogen 211At has been attached to an antibody by using an acylation reaction to conjugate para-[211At]astato-benzoic acid with rabbit IgG. The conjugate, which is stable in vivo, contains at least 30% of the initial activity of 211At.

The synthesis of benzylamines with various N-alkyl chains and substituents in the aromatic system as well as their evaluation on Mycobacterium tuberculosis H 37 Ra are described. The most active compounds in this test, N-methyl-3-chlorobenzylamine (19, MIC 10.2 micrograms/mL), N-methyl-3,5-dichlorobenzylamine (93, MIC 10.2 micrograms/mL), and N-butyl-3,5-difluorobenzylamine (103, MIC 6.4 micrograms/mL), ...

3-Hydroxy-sulfanilamide (3-HS), a biotransformation product of sulfanilamide, 3-hydroxy-para-aminobenzoic acid (3- HPABA ), a biotransformation product of procaine and para-aminobenzoic acid, as well as 5-aminosalicylic acid (5-ASA), a bacterial split product of salicylazosulfapyridine (Sulfasalazine, Salazopyrin ) in the gut, were shown to react spontaneously with and to bind covalently to proteins ...

This is the second report of Mycobacterium thermoresistibile as the etiological agent of a pulmonary granuloma and the first occurrence of this organism in a patient who has not been outside the continental United States. The organism is susceptible to rifampin, ethambutol, and streptomycin but resistant to isoniazid and p-aminosalicylic ...

3-Hydroxy-para-aminobenzoic acid (3-HPABA), a biotransformation product of procaine and para-aminobenzoic acid, is capable of binding covalently to proteins by simple incubation at alkaline pH. When administered incorporated in Freund adjuvant to rabbits, 3-HPABA conjugates with normal rabbit serum proteins (3-HPABA-NRS) give rise to both hapten specific antibodies and anti-NRS antibodies. ...

Sunburn, wrinkling and malignancies are the frequent results of excessive sun exposure. Photosensitivity and photoallergic or phototoxic reactions are less commonly observed. Sunscreens containing para-aminobenzoic acid (PABA), PABA esters and benzophenones offer substantial protection, allowing even fair-skinned persons to participate freely in outdoor activities. These products are now rated and ...

The possible testicular effects resulting from occupational exposure to para-tertiary butyl benzoic acid (p-TBBA) were studied in 90 male volunteers employed at the Martinez, California, facility of the Shell Chemical Company. The comparison data used were obtained from an external reference group of 103 male volunteers not exposed to any ...

When grown on Czapek-Dox agar, Penicillium brevicompactum produced mycophenolic acid after a vegetative mycelium had been formed and as aerial hyphae were developing. Nutrients were still plenteous in the agar when the synthesis began. If aerial hyphal development was prevented by placing a dialysis membrane over the growing fungus, no ...

m-Toluidinyloxamic acid is shown to be about as efficient as the para isomer as a gravimetric reagent for La, Pr and Nd. Conditions have been established for the determination of these lanthanides in presence of a number of metal ions.

1 The responses of excitatory junctions on locust skeletal muscle fibres to iontophoretically applied L-glutamic acid and DL-ibotenic acid, a rigidly extended analogue of glutamate, were recorded by means of intracellular microelectrodes.2 Iontophoresis of L-glutamate to junctional sites produced transient depolarizations. Ibotenate applied iontophoretically to these sites usually evoked small ...

Synopsis A method is presented for the identification and determination by T.L.C. and G.L.C. of esters of para-aminobenzoic acid with a free amine function and of local anaesthetics, prohibited in cosmetic products, in accordance with the cosmetic directive 76/768/EEC. In a commercial product, nominally supplied as para-aminobenzoic monoglyceryl ester (authorised ...

Six new monogenetic trematodes are described from Nebraska fishes: Gyrodactylus bulbacanthus sp. n. from Fundulus kansae (Garman); G. callawayensis sp. n. from Notropis lutrensis (Baird and Girard); G. eos sp. n. from Phoxinus eos (Cope); G. nebraskensis from Phoxinus neogaeus (Cope); G. planensis from Notropis dorsalis (Agassiz); and Dactylogyrus pectenatus ...

Mycophenolic acid is an antimetabolite used experimentally for the treatment of psoriasis. Thirty-eight patients were treated with mycophenolic acid. A double-blind, placebo-controlled study demonstrated the efficacy of mycophenolic acid (P less than .01). A long-term safety study showed the occurrence of hematologic abnormalities, viral infections, and carcinoma. The position of ...

Studies on acetylation of sulfadiazine, isoniazid, and p-aminobenzoic acid in selected lines of slow and rapid acetylator rabbits are described. Pedigree analysis of rabbits classified as slow or rapid sulfadiazine acetylators confirmed previous studies that the rate of sulfadiazine elimination (acetylation) is genetically controlled, with rapid elimination dominant over slow ...

Eighty tuberculous meningitis patients who were seen in the neurological clinics in Surabaya between the January 1971 and January 1975 were asked to cooperate in a double blind clinical trial. One group was given isoniazid, streptomycin and p-aminosalicylic acid, the other group was given isioniazid, rifampicin, ethambutol and a protease. ...

Studies performed on the intrarenal distribution of nalidixic acid in dogs show that this weak organic acid is indeed accumulated in the kidney, the highest concentration being attained in the cortex and followed in order by the outer medulla, papillae, and inner cortex. Our results also show that nalidixic acid ...

Thermodynamic ionization constants of para-substituted N-phenylbenzohydroxamic acids have been determined in dioxan-water mixtures at 35 degrees . The plot of mole fraction of dioxan vs. pK(a) is linear at this temperature, whereas that of pK(a)vs. 100/D is linear over a narrow range of dielectric constants (D) but at higher mole ...

Treatment of mice with a nonimmunogenic preparation of free reactive hapten, trinitrobenzene sulfonic acid (TNBS), leads to the induction of a state of tolerance to the hapten, 2,4,6-trinitrophenyl (TNP). This is determined by the lack of response to the haptenic moiety in an immunogenic hapten-carrier conjugate (TNP-SRBC) as assayed both ...

Section freeze-dry radioautography has been used to examine the intrarenal distribution of a water-soluble organic acid (para-aminohippuric acid (PAH-3H)) under constant-infusion, steady-state conditions in mouse and rat kidney in vivo. The technique described here has the following advantages: (a) Sectioning and freeze-drying are accomplished in a closed cryostat at temperatures ...

Bresica-Cimino shunts inserted to facilitate intermittent dialysis may markedly increase the circulatory load on the heart. Three patients in whom there was evidence of overload are described. Thorough investigation of the cardiac output should be made in patients with fistulae of this kind, which should be closed as soon as ...

In screening for anonymous mycobacteria the use of thiosemicarbazone (10mug./ml.) may give rise to false positive results. Although these can usually be overcome by further tests, additional time and effort is required, which seriously limits the value of thiosemicarbazone as a true screening agent. Para-nitrobenzoic acid (500 mug./ml.) has proved ...

The antidotal potency of a cobalt salt (acetate), of dicobalt edetate, of hydroxocobalamin and of cobinamide against hydrocyanic acid was examined mainly on mice and rabbits. All the compounds were active antidotes for up to twice the LD50; under some conditions for larger doses. The most successful was cobalt acetate ...

The history of Lister's introduction of the antiseptic system is recalled and the circumstances surrounding the original use of carbolic acid for wound treatment, which took place in the Royal Infirmary, Glasgow, on August 12, 1865, are reviewed. The fact that wound sepsis is still prevalent is emphasized, and recent ...

A mathematical model, involving three consecutive first order reactions, has been applied to already existing experimental material in order to explain the hourly variation in serum levels obtained after administration of varying repeated doses of different preparations of p-aminosalicylic acid to human volunteers. The model closely agrees with the experimental ...

Little being known of the effect of artificial conditions on Biomphalaria snails maintained in laboratory aquaria, experiments were conducted to determine some of the basic requirements of these snails, expressed in terms of the influence of various factors on their growth, fecundity and mortality. Among the factors studied were diet, ...

In a comparison of home and sanatorium treatment for tuberculous patients in India, pretreatment cultures of tubercle bacilli showed a higher average level of resistance to p-aminosalicyclic acid (PAS) than pretreatment cultures from a representative sample of patients in Great Britain. The investigation described in the present paper was therefore ...

Streptomycin resistance of a high degree has been induced in sensitive populations of Hemophilus influenzae and Hemophilus parainfluenzae by desoxyribonucleic acids (DNA's) derived from streptomycin (SM)-resistant cells of at least one heterologous species of Hemophilus. The specificity of the DNA which controls SM resistance has been studied within and among ...

Resistance to streptomycin, of a degree exceeding 1000 microg. per ml., has been induced in sensitive strains of Hemophilus influenzae by exposure for 10 minutes to desoxyribonucleic acid-containing extracts isolated from a strain of type b Hemophilus influenzae which had emerged resistant to 1000 microg. of streptomycin per ml. DNA ...

Previous studies have shown that when Staphylococcus aureus becomes resistant to sulfonamides, an antisulfonamide substance is produced in the growth medium. Although these studies suggested that the substance was p-aminobenzoic acid (PABA), isolation and positive identification were not achieved. Because of the importance of these observations, unequivocal identification of the ...

p-Aminobenzoic acid (PABA) exerts three metabolic effects on E. coli: it acts as a normal vitamin at low concentrations, as a source of another vitamin, p-hydroxybenzoic acid (POB), at moderate concentrations, and as a growth inhibitor at high concentrations (150 to 1600 microg./ml.). The inhibition is competitively reversed by POB ...

By injection into typhus-infected yolk sacs, a number of agents were tested for possible inhibition or acceleration of rickettsial growth. The previously reported rickettsiostatic activity of penicillin was further confirmed. Para-aminobenzoic acid, in single injections of 6.6 mg. and 3.3 mg. giving initial concentrations of approximately 1:6000 and 1:12,000 was ...