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INTRODUCTION: After 29 years, rabies was detected in a cat in Curitiba, southern Brazil. METHODS: The fluorescent antibody test (FAT) and mouse inoculation test (MIT) were performed on central nervous system (CNS) samples. RESULTS: Direct immunofluorescence was negative, but the biological test was positive and rabies virus was characterized as variant 4 (from Tadarida brasiliensis). CONCLUSIONS: Reappearance of rabies in domestic animals warns of sylvatic-aerial risk of infection and the necessity of monitoring bats in historically rabies-free areas. INTRODUÇÃO: Após 29 anos, raiva em um gato foi detectada em Curitiba, sul do Brasil. MÉTODOS: Foram realizados imunofluorescência direta e prova biológica através de inoculação em camundongos para o diagnóstico da raiva. RESULTADOS: A imunofluorescência direta foi negativa, mas a prova biológica foi positiva e o vírus caracterizado como variante 4 (de morcegos não hematófagos). CONCLUSÕES: O reaparecimento da raiva alerta para o risco aéreo-silvestre de infecção e para a necessidade de monitoramento de morcegos em áreas historicamente livres da raiva.

Biofuel production from algae oil is one of the most attractive process technologies. Few principles of algae cell disruption are presented on the market and introduced on the conference. Mainly, mechanical, thermal and ultra-sonication technologies are widely used in biofuel production. In this paper, authors propose a novel method for algae cell disruption – electrohydraulic shock in the water (Yutkin effect). The short-term plasma can be determined as an effective method for algae cell wall disruption. The experimental results using the proposed method as well as the biological test performed using Scenedesmus algae specie are presented

Aquatic food accounts for over 40% of global animal food products, and the potential contamination with toxins of algal origin – marine biotoxins – poses a health threat for consumers. The gold standards to assess toxins in aquatic food have traditionally been in vivo methods, i.e., the mouse as well as the rat bioassay. Besides ethical concerns, there is also a need for more reliable test methods because of low inter-species comparability, high intra-species variability, the high number of false positive and negative results as well as questionable extrapolation of quantitative risk to humans. For this reason, a transatlantic group of experts in the field of marine biotoxins was convened from academia and regulatory safety authorities to discuss future approaches to marine biotoxin testing. In this report they provide a background on the toxin classes, on their chemical characterization, the epidemiology, on risk assessment and management, as well as on their assumed mode of action. Most importantly, physiological functional assays such as in vitro bioassays and also analytical techniques, e.g., liquid chromatography coupled mass spectrometry (LC-MS), as substitutes for the rodent bioassay are reviewed. This forms the basis for recommendations on methodologies for hazard monitoring and risk assessment, establishment of causality of intoxications in human cases, a roadmap for research and development of human-relevant functional assays, as well as new approaches for a consumer directed safety concept. info:eu-repo/semantics/publishedVersion

Alternative toxicological methods used in Russia to assess safety of food and non-food products have been reviewed. Along with traditional toxicological methods of monitoring various alternative toxicological study techniques are used to assess product safety. Those are methods using biological test-objects, so-called biological test methods, or in vitro methods which are allowed to be used from the legislative viewpoint. Alternative toxicological methods are based on risk degree assessment of the studied object by response of living organisms (test-objects) to adverse factor exposure. Information resulting from applied bio-testing methods represents combined toxic effect of all toxicants present in the given medium and their simultaneous presence. When assessing product safety by toxicological indices using alternative biological models, general toxic and irritating effects are to be studied and the test-objects are cattle semen, luminescent bacteria, chick egg chorioallantoic membrane, human and animal cell cultures and isolated organs. In vitro methods with cattle semen and luminescent bacteria playing the role of test-objects are also used to assess alcohol product toxicity, in particular spirits and vodkas. Thus, alternative study methods are widely known and commonly used in practice to prove safety of consumer goods and alcohol-containing foodstuffs.

Injection of Egyptian toads Bufo regularis, with adriamycin subcutaneously in the dorsal lymph sac at a dose level of 0.1 mg/toad, once every 3 weeks for 3 months induced pronounced alterations in the blood cells. These alterations were more or less similar to the criteria reported in human leukaemia. These changes were all comparable to those observed after the treatment of the experimental animals with the chemical carcinogen 7,12-dimethylbenz(a)anthracene. It is speculated that toads (Bufo regularis) can be used as biological test animals for screening chemicals or drugs which induce leukaemia in man.

Methods are described for the removal of adenosine or purine nucleotides from extracts of bovine retractor penis muscle (BRP). These methods did not interfere with the biological test preparations. Removal of adenosine and purine nucleotides by these methods did not modify the inhibitory action of the extract on the BRP. The effect of the extract on the BRP resembles that of inhibitory nerve stimulation. If the inhibitory substance present in the extract is the inhibitory transmitter, then the results indicate that, in this tissue, the transmitter is neither adenosine nor a purine nucleotide.

of time to permit the establishment of the is still a matter of debate and hence the true vitamin value of any foodstuff. tests for this factor are as yet unsatisPending the isolation of each vitamin and factory. an accurate method of assay, we must When we consider that the existence of develop the biological test to as high an vitamins was unknown less than 16 years accuracy as possible. It would extend ago, the outlook for proper assay of these this paper too greatly to review the story factors is encouraging in spite of the of measurement of vitamins D and E. limitations we have noted. Owing to the sharpness of the pathological picture, D measurements are fairly REFERENCES satisfactory, but little data has yet been 1. Sherman & La Mer, & Campbell. J. Am. Chem. Soc. 44:165, 1922. obtained. Hess has reported a general 2' Lewis, H. B. J. Biol. Chem., 40:91, 1919. absence of D in green vegetables tested, 193. Drummond and Coward. Biochem. J., 14:661, such as lettuce, spinach, etc. We have 4. Zilva and Miura. Biochem. J., 15:654, 1921. confirmethis finding in the case of peas. 5. Sherman and collaborators. J. Am. Chem. Soc., confirmed tnls nnalng ne case OI pea47:1639-1662, 1925. We have not yet tested bananas for this 6. Sherman and Munsell. J. Am. Chem. Soc., 47:1634, 1925. Hazel Munsell; Dissertation, Columbia factor. The very existence of vitamin E University (1924).

Several compounds related to helminthosporol (I), a natural plant-growth promoter, were prepared from I and their plant-growth regulating activities were examined together with those of the derivatives reported in the previous paper, using rice and lettuce seedlings. Among the compounds tested, helminthosporic acid (III) exhibited marked elongation effect to the shoot growth of rice and lettuce seedlings, whereas the effect of I was specific to the former. Results of the biological test are reported in details.

Nutritional damage to animal products during processing is not always reflected in amino-acid assays of acid hydrolysates of these materials (Bissett and Tarr, 1954). In the present study a biological measure of protein quality has been compared with values from a chemical method designed to estimate “available lysine,” on the basis that it is thought to be the e-NH2 group of lysine that reacts to form a nutritionally-unavailable complex when intact proteins are damaged. The biological test was a modification (Carpenter, Ellinger and Shrimpton, 1955) of the “gross protein values” (G.P.V.) method using the response of chicks when 3% of protein from test materials supplements a basal “cereal and vitamin” mixture contributing 8% protein (Heiman, Carver and Cook, 1939). The chemical method followed that used to study free-NH2 groups in purified proteins by their reaction with 2,4-dinitrofluorobenzene (DNFB) to give stable dinitrophenyl- (DNP-) compounds (Sanger, 1945). Suspensions of test material …

A bright yellow, crystalline compound, m.p. 271–274°, isolated from the root-bark of Hiptage madablota Geartn. has been identified as mangiferin, 1,3,6,7-tetrahydroxy-2-C- β -D-glucosylxanthone, by direct comparison of its properties and those of its derived 3,6,7-trimethyl ether with those of authentic samples. Mangiferin was assayed in three biological test systems and the results are given.

THE importance of vitamin B for the growth and development of insects has been stressed by several investigators. But very little is known of the ingredients of the vitamin B complex which are actually required by the insects.

Evidence has been presented1 for the existence in all types of living tissue of a substance which has been named “pantothenic acid”. A quantitative biological test based upon yeast growth which is specific for this substance has been developed.While marked progress has been made in this laboratory in concentrating and purifying the acid it is unlikely that any chemical method for its determination can be devised for some time to come. In order to learn something of its functions, however, it seemed desirable to obtain approximate information as to the content of various animal tissues.Each of the tissues indicated below was thoroughly ground and extracted with a large volume of hot water, usually 100 times its weight. The pantothenic acid which is not “bound” in the tissues is thus extracted, and that which in some cases, at least, is “bound” is not determined. The numerical values are based upon the pantothenic acid extracted from a unit weight of moist tissue, in comparison with that in a unit weight of...

INTRODUCTION THE AVAILABLE lysine test of Carpenter and Ellinger (1955) could not be applied generally to proteins of plant origin without modifications; and even then, it would not be as reliable as it is in the case of proteins of animal origin. Plant proteins, in general, lack more than one essential amino acid, and for this reason prediction of their nutritive value through their available lysine content alone is a matter still to be proved. On the other hand, physical techniques of protein solubility in various solutions were reported by Anwar (1957) to work as grading tests for protein quality of plant origin. His results could be summarized as follows: in the case of cottonseed meals the residual protein fraction as determined by the Lund-Sanstrom fractionation technique (1943) seems to be the most reliable fraction in the prediction of their nutritive value. The globulin protein fraction, though with significant results, …

This study aimed to establish a rapid and reliable biological test using chick embryos for estimation of toxicities of various substances contained in foods.Tetrodotoxin was tested in this experiment. The sample dissolved in acetic acid solution, pH 3.5 was inoculated into air cells or yolk sacs of White Leghorn fertile eggs aged three to seven days and toxicity of the sample was estimated by their mortalities during three days after inoculation. All the chick embryos proved more sensitive to air cell inoculation than yolk sac one, among which five day-old eggs were most sensitive.Therefore, it is considered that the method with air cell inoculation using five day-old chick embryo is preferable concerning both sensitivity and reliabilty. Moreover, it was found that the chick embryo test was more excellent than the toxicity test using mouse because of its good sensitivity and reproducibility.

Testicular damage as measured by decreased incorporation of labeled tracers, testes weight, or testes DNA content has been investigated as a possible biological test system for intercomparing fast ...

(ONSIDERABLE attention has been given during recent years to the . fate of herbicides sprayed onto soil surfaces. The effect of light upon herbicides also has been studied extensively. Payne and Fults by means of a biological test found that the potency of 2,4-D was increased by exposure to ultraviolet light (7). Hansen and Buchholtz found that when a solution containing 2,4-D and riboflavin was exposed to light the activity of 2,4-D was reduced (5). They tentatively identified the breakdown product as 2,4-dichlorophenol. Later Bell positively identified it (1). Hill et al. found that 83 percent of the 3-(p--chlorophenyl)-l,1dimethylurea (monuron) was lost when exposed to sunlight for 48 days (6). Birk found that photodecomposition was a factor in the disappearance of monuron (2). Woodford concluded that photodecomposition is of practical importance only in areas where little rain occurs and the herbicides remain on the soil surface for prolonged periods (9). It was shown by Dorschner and Buchholtz and others that spectrophotometric analysis of herbicides is a rapid quantitative technique (3). 3-(3,4-dichlorophenyl)-l,l-dimethylurea (diuron) is used in Wyoming for the control of annual weeds in alfalfa (8). The applications are made in the spring, and often precipitation does not occur for several weeks. Because of the absence of moisture including dew, there are optimum conditions for photochemical reactions. The objectives of the experiment were to determine (1) the effect of a controlled light source upon monuron and diuron and (2) the biological activity of any changed material.

Early studies of the relative effectiveness of different qualities of ionizing radiation, reviewed by Packard (1), were chiefly concerned with the effect of X-rays of therapeutic quality on small biological test objects. A more recent review by Zirkle (2) has summarized biological studies that have used a broad range of radiation qualities in an effort to correlate response to the energy transfer involved. Acute radiation death in mammals has not been widely employed as a criterion of relative effectiveness of X-rays in the therapeutic range. Potter (3) demonstrated a relationship between exit dose and lethality in rats with 100and 400-kvp X-rays wherein equal effect was noted when the exit doses were similar for compared qualities. A like relationship was observed by Ellinger et al. (4) for the exit dose and LDso in mice exposed to 140and 200-kvp X-rays. The implication that nonuniformity of depth dose can account for variation in effectiveness of X-rays has not been well established. Thus, the present study examines the relationship of acute lethality and depth-dose distribution in mice and rabbits exposed to X-rays ranging from 80 to 250 kvp.

A determination of the relative biological effectiveness (RBE) of Co60 gamma rays and 22-Mewp x rays versus 200-kvcp x rays was made, with lethality in the 4-day old chick embryo as the biological test object. A series of six simultaneous experiments was run with viability scored at 7 hr after the beginning of irradiation. The LD50 doses were 10l5 rads for 200-kvcp x rays, 1100 rads for Co60 gamma rays, and 1090 rads for 22-Mewp x rays. The RBE values obtained from this series were 0.92 for Co60 gamma rays versus 200-kvcp x rays; 0.93 for 22-Mewp x rays versus 200-kvcp x rays ; and 1.007 for 22 Mevp x rays versus Co60 gamma rays. Two experiment: were conducted with viability scored at 10 days after irradiation, with similar results.

TWENTY-SEVEN authors contribute to this symposium, which will be welcomed by all who have to deal with any aspect of cancer. The papers, some of which are highly technical, are reprinted from many journals and form four main groups: three of general clinical interest; four on radiation therapy; eight on calculations and physical measurements of radiation; eighteen on experimental research, and a review of the world literature 1938–1939 on chemical compounds as carcinogenic agents. The latter paper, by Profs. Cook and Kennaway, follows an earlier review on the same subject and is a masterly piece of work, including a bibliography of some five hundred new references. About half the volume is concerned with the synthesis and testing of chemical carcinogens and growth inhibitors. It is not yet certain that any of these substances are directly related to human cancer other than industrial cancer. A careful perusal of the results shows that many new facts could not have been established by studying only the earliest and best-known carcinogenic hydrocarbons. To the reviewer, the most interesting new experiments are those dealing with growth-inhibiting hydrocarbons that are not necessarily carcinogenic; with carcinogens that act on remote organs as well as locally; with those that show the need for more than one kind of biological test before a substance can be regarded as non-carcinogenic; and, particularly, with the extraction from human livers (not necessarily from cancer subjects) of unidentified carcinogens. Selected Papers from the Royal Cancer Hospital (Free) and the Chester Beatty Research Institute Published by order of the Governors of the Royal Cancer Hospital (Free), London. Vol. 2. Pp. viii + 414. (London: Royal Cancer Hospital (Free), 1943.) 16s.

Dreyer's demonstration that splanchnic stimulation increased the content of adrenal secretion in blood from the adrenal veins has been confirmed by several observers. Adrenal secretion therefore is under control of the sympathetic system.Major emotional disturbances indicate the dominance of sympathetic impulses. In the cat, for example, fright causes dilation of the pupils, inhibition of the stomach and intestines, rapid heart, and erection of the hairs of the back and tail. Do not the adrenal glands share in this widespread subjugation of the viscera to sympathetic control?To try this suggestion the inhibition of contraction in strips of longitudinal intestinal muscle, sensitive to suprarenin 1:20,000,000, was used as a biological test. Blood was obtained from the cat when quiet, and again after the animal was excited by the presence of a barking dog, by introducing, through the femoral vein, into the inferior vena cava to the region of the liver, a small vaselined catheter. The blood thus obtained was ...

The work reported in this paper was undertaken at the suggestion of A. J. Carlson, primarily for establishing a biological test for the active principle of the thyroid gland in the blood. A few years ago Hunt,1by means of the acetonitril test, thought that he had a reliable test for the active principle of the thyroid in the blood. Later investigators (Carlson and Woelfel,2Lussky3) failed to detect any active principle of the thyroid in the blood of the dog, and in rabbits and guinea-pigs in experimental hyperthyroidism by means of this test. Hunt studied the blood of clinical cases of exophthalmic goiter and obtained a positive test in two out of three cases. On the other hand, Carlson and Woelfel could not get a positive reaction in a case studied by them. Carlson also tested his own blood after having taken thyroid until toxic

It is known that in the human conceptus, serum a1-fetoprotein reaches a maximal concentration at approximately 13 weeks, then decreases and disappears 1 or 2 weeks after birth. In the first step of this workm the existence of a1-fetoprotein has been studied in the serum of three groups of neonates (premature, full term, and small for date). Electrophoresis on polyacrylamide gels and immunoelectrophoresis with a specific antibody against human a1-fetoprotein have been chosen: since they have a different degree of sensitivity, they can be used as a semiquantitative test. At birth, small for date infants have no a2-fetopretein or a very low concentration; the concentration is higher in full term babies and still higher in prematures. These observations suggest that a distinction between small for date and premature babies is possible by such a procedure. In the second step of this study. Mancini's immumochemical method for a1-fetoprotein quantitative estimation is in process in order to see, especially in premature babies, whether serum a1-fetoprotein concentration at birth is directly related to the length of gestation. If so, we shall have a simple biological test for the assessment of the gestational age of newborn infants.

WE have shown1 that the fluorimetric assay2 of vitamin B1 in milk gives values about 50 per cent lower than the biological test. The difference was not due to the presence in milk of free cocarboxylase or of the monophosphate, as in no case could more than a trace of fluorescence due to oxidized phosphorylated aneurin be observed in the aqueous layer after extraction with iso-butanol.

Low amounts of menopause or castration prolan which are difficult to recognize by the usual tests can easily be recognized by combining this substance with definite amounts of pregnancy prolan. The level of pregnancy prolan chosen is a low one but is always somewhat in excess of the minimal effective level when administered by itself. By the employment of this synergic reaction, rats prove to be just as sensitive test objects as are mice for the recognition of menopause or castration prolan.A single example may be given. The administration of a gram of the alcohol precipitate from the urine of a castrated woman injected into 3 immature female rats, gave ovarian weights averaging 26 mg. and small or medium follicles only. When combined with levels of pregnancy prolan which alone gave ovarian weights averaging 30 mg., the combination yielded ovarian weights averaging 150 mg. In this case the hormone could not have been recognized in rats without the synergic reaction. It is remarkable that the “synergic” ov...

To the Editor.— We agree that the indirect immunofluorescent (IIF) technique does require more standardization before a high degree of correlation, in terms of sensitivity, specificity, and reproduceability, can be expected between the various laboratories performing the test. Biological testing systems are notoriously fraught with these problems. They are still of a major concern, even in the STS (serologic test for syphilis) test which Dr. Beutner states is a reliable test and similar problems have plagued the basophil degranulation test and the FTA-ABS (fluorescent treponemal antibody absorption) test. Any interpretation of the results of reading immunofluorescence is subjective and will remain so until some objective means of rating becomes available. Our "house rules" also demand that two investigators read each slide and report independently on the findings. In addition to the difficulties inherent in a biological test dependent on subjective interpretation, the choice of the substrate in the IIF technique

FOR some time past the effect of various factors on the vitamin content of milk of a typical English herd has been under investigation in this Institute. In the course of this work an endeavour has been made to measure the rather low vitamin C potency of milk, using guinea pigs for the biological test.