Granuloma pouch and skin histamine of the rat

Using the granuloma pouch technique of SELYE, effect of modification in local histamine on the inflammatory tissue reactions was examined in rats. The increase in the weight of pouch wall and histological inflammatory changes were distinctly inhibited in either case of histamine depletion by sinomenine and of desensitization to histamine by repeated injections of histamine. In rats injected with aminoguanidine, the skin and local histamine contents increased in similar degree as those in rats receiving histamine injection, but the inflammatory tissue reactions were severer than in the control. The total histamine of the pouch wall during inflammation reached the maximum four days after the injection of croton oil and decreased thereaftcr. The prcliferative processes indicating the recovery of injured tissues in later stages of the inflammation were the most vigorous in rats treated with histamine and this was in contrast to the extreme weakness of this tendency in animals in which the local histamine had been depleted. These observations not only suggests the fairly close relationship of histamine to carly reaction of inflammation but also indicates the role of histamine in its recovery processes.</p

Experimental studies of the endolymphatic radiotherapy

By injecting 131I-Lipiodol into lymphatics of the dorsum of dog feet, the distribution of 13JI in the lymph nodes and other principal organs as well as its histological effect were studied periodically after the injection for the period of two months. The characteristic feature of J3JI distribution was the fact that J31I was accumulated into lymph nodes markedly higher than in any other organs and it was retained there over a long period of time. Histological examinations of the lymph nodes revealed a marked lymphocytopenia, the loss of germinal center, practically complete loss of lymphoid elements already 5 days after injection, and marked fibrosis. In the lung a considerable J3JI·distribution could be seen in early stage:, but with lapse of time it decreased rapidly. The distribution in other organs such as liver, spleen, bone marrow, kidney, ureter, bladder, thyroid gland, pancreas, testicles and small and large intestines was negligible in amount, and any specific histologic effect of irradiation could not be recognized in these organs including the lung. From these results, the authors concluded that 131I-Lipiodol has a selective activity on lymph nodes by injecting it via lymphatics and it is a safe method in clinical application to treat the patients bearing malignant lymphoma or metastatic lymph nodes.</p

Clinical evaluation of endolymphatic radiotherapy in malignant lymphoma

By endolymphatic injection of radioisotope 131I.Lipiodol, so.called endolymphatic radiotherapy, we treated 10 cases with malignant lymphoma and found a marked tumor reduction to normal size in all the 10 cases we tried. It seems that this method is one of the most effective therapeutic methods for malignant lymphoma, espe. cially invading into the retroperitoneal lymph nodes.</p

Virulence profile comparison between LEE-negative Shiga toxin-producing Escherichia coli (STEC) strains isolated from cattle and humans

For comparison purposes, the prevalence of 8 virulence markers was investigated, by PCR, in 153 cattle and 47 human Locus for Enterocyte Effacement (LEE)-negative Shiga toxin-producing Escherichia coli (STEC) strains isolated in Argentina. Also, their correlation with severe disease was established. The virulence markers studied comprises 5 fimbrial and nonfimbrial adhesin-encoding genes (fimA, iha, efa1, lpfAO113, and saa) and 3 toxin genes (cdt-V, subAB and astA) in addition to the Shiga toxins. The most prevalent virulence marker found was that encoded by the lpfAO113 gene (199/200, 99%). Comparatively, the lpfAO113, fimA, iha, saa, subAB, cdt-V and astA genes were detected in 100%, 92.8%, 85%, 52.9%, 36%, 11.8% and 9.8% of the cattle strains and in 97.9%, 95.7%, 89.4%, 40.4%, 32%, 17% and 10.6% of the human strains, respectively. All STEC strains were efa1 negative. The most prevalent profile observed among cattle and human STEC strains was lpfAO113 iha fimA. These results show that bovine LEE-negative STEC strains possessed genes encoding virulence factors present in human LEE-negative STEC strains that are associated with disease. Despite a great diversity of virulence profiles observed, further studies comparing wild type strains and their allelic mutants are needed to evaluate the role of each factor in the pathogenesis of LEE-negative STEC strains during human infections.Fil: Galli, Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; Argentina. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; ArgentinaFil: Miliwebsky, Elizabeth. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; ArgentinaFil: Irino, Kinue. Instituto Adolfo Lutz; BrasilFil: Leotta, Gerardo Anibal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; Argentina. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; ArgentinaFil: Rivas, Marta. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; Argentin

Effect of histamine releasers and of anti-inflammatory drugs on the egg-white edema of rat's hind paws in relation to skin histamine

1. A method was described for a fairly accurate judgement of the effect of drugs inhibiting the edema in hind paws of a rat caused by local injection of egg white. 2. The degree of inhibition of egg-white edema by single doses of sinomenine, compound 48/80, or dextran was in parallel with histamine reduction in skin and other tissues of the paws (and the skin of abdomen), although prevention of the edema by prolonged treatment with sinomenine was incomplete even when the releasable histamine of the skin was practically exhausted. 3. Sodium salicylate, aminopyrine, butazolidine sodium, cortisone, and guaiazulene were capable of inhibiting egg-white edema without modifying the content of skin histamine. These drugs and a small dose of phenergan potentiated the inhibition by dextran of egg-white edema and inhibited the release of histamine by dextran. These actions lasted for over 24 hours with the exception of guaiazulene. 4. Irgapyrin and a large dose of phenergan, which possess actions of histamine release and of histamine release inhibition and also antihistaminic action, caused a slight reduction of skin histamine and a comparatively marked inhibition of the edema. 5. In adrenalectomized or hypophysectomized rats, the edema-inhibiting effect of salicylate and aminopyrine decreased but that of cortisone increased. The effect of guaiazulene remained unchanged. 6. The observations that inhibition of egg-white edema is caused by (a) histamine releasers, (b) histamine-release inhibitor, and (c) drugs exerting both histamine release and inhibition of the release were discussed with the consideration to a relationship between egg-white edema and skin histamine.</p

Histamine release inhibition in anti-inflammatory mechanism

Rats were depleted of skin histamine by more than 80 % by intraperitoneal injections of sinomenine with daily increasing doses for 6 days. In these rats, egg-white edema induced in the hind paws was inhibited by 68 % of control. The weight of the wall of granuloma pouch made by croton oil was also evidently smaller in the rat treated similarly with sinomenine than that of control. This suggests an important role of histamine participating in the inflammation. It has been observed that a variety of non-steroidal anti-inflammatory drugs inhibited both degranulation and histamine release induced by compound 48/80 of mast cells isolated from rat peritoneal fluid. The degranulation inhibiting actions of anti-inflammatory drugs were markedly decreased in the presence of glucose as in cases of dinitrophenol, dicumarol and warfarin which are known uncouplers of oxidative phosphorylation. Also, prevention of edema provoked by anti-rat serum is roughly correlated to a potency of degranulation inhibiting effect of anti-inflammatory agents. These observations suggest that there is a common mechanism between these two phenomena, and the prevention of mast cell degranulation by the anti-inflammatory agents is, at least, partially due to their uncoupling effects. A working hypothesis explaining the process of edema formation at the inflammatory site has. been made based on the data of the present experiment and other ob3ervations: a leakage of plasma into the tissue space from the gap between two adjacent endothelial cells which are contracted by released histamine may activate a kinin-forming system in the plasma, and kinin(s) may further aggravate a leakage. The mechanism of action of anti-inflammatory agents, which interfere with the histamine effect in inflammation, should be understood in twofold: one is prevention of histamine release from the tissue, mainly by inhibiting mast-cell degranulation, and the other is prevention of the contraction of endothial cells by their uncoupling activities.</p

The Sites of Action of some Histamin-Releasing Substances in the Dog

1. The rates of histamine release from the liver, skin and muscle by four kinds of histamine-releasing substances, sinomenine, compound 48/80, tween 20 and polyvinylpyrrolidone (PVP), were compared by intravenous injection in dogs, each in a dosage to cause a fall of approximately 80 per cent in the arterial blood pressure. 2. By compound 48/80, the rates were especially marked from the liver and muscle and only slight from the skin, while those by sinomenine, tween 20 and PVP were largest from the skin, followed by those from the liver and muscle, in that order. The rate of histamine release from the skin by PVP was characteristic in that it was far larger than that by other releasers. 3. On direct application of the drug solutions to the excised tissues of the liver and skin the rates of release of histamine differed only slightly by the tissue in any of these releasers 4. Some considerations were given on the reason for the different ratios by the organ of in vivo histamine release though as yet no definite conclusion could be drawn.</p

Genotypic Characterization of Non-O157 Shiga Toxin–Producing Escherichia coli in Beef Abattoirs of Argentina

The non-O157 Shiga toxin-producing Escherichia coli (STEC) contamination in carcasses and feces of 811 bovines in nine beef abattoirs from Argentina was analyzed during a period of 17 months. The feces of 181 (22.3%) bovines were positive for non-O157 STEC, while 73 (9.0%) of the carcasses showed non-O157 STEC contamination. Non-O157 STEC strains isolated from feces (227) and carcasses (80) were characterized. The main serotypes identified were O178:H19, O8:H19, O130:H11, and O113:H21, all of which have produced sporadic cases of hemolytic-uremic syndrome in Argentina and worldwide. Twenty-two (7.2%) strains carried a fully virulent stx/eae/ehxA genotype. Among them, strains of serotypes O103:[H2], O145:NM, and O111:NM represented 4.8% of the isolates. XbaI pulsed-field gel electrophoresis pattern analysis showed 234 different patterns, with 76 strains grouped in 30 clusters. Nine of the clusters grouped strains isolated from feces and from carcasses of the same or different bovines in a lot, while three clusters were comprised of strains distributed in more than one abattoir. Patterns AREXSX01.0157, AREXBX01.0015, and AREXPX01.0013 were identified as 100% compatible with the patterns of one strain isolated from a hemolytic-uremic syndrome case and two strains previously isolated from beef medallions, included in the Argentine PulseNet Database. In this survey, 4.8% (39 of 811) of the bovine carcasses appeared to be contaminated with non- O157 STEC strains potentially capable of producing sporadic human disease, and a lower proportion (0.25%) with strains able to produce outbreaks of severe disease.Fil: Masana, Marcelo. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Agroindustria. Instituto de Tecnología de Alimentos; ArgentinaFil: D´Astek, B. A.. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; ArgentinaFil: Palladino, Pablo Martín. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Agroindustria. Instituto de Tecnología de Alimentos; ArgentinaFil: Galli, Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; Argentina. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas; ArgentinaFil: del Castillo, Lourdes Leonor. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Agroindustria. Instituto de Tecnología de Alimentos; ArgentinaFil: Carbonari, Claudia Carolina. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas; ArgentinaFil: Leotta, Gerardo Anibal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; Argentina. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas; ArgentinaFil: Vilacoba, Elisabet. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas; ArgentinaFil: Irino, K.. Instituto Adolfo Lutz. Seção de Bacteriologia; BrasilFil: Rivas, M.. Dirección Nacional de Institutos de Investigación. Administración Nacional de Laboratorios e Institutos de Salud. Instituto Nacional de Enfermedades Infecciosas; Argentin

Antitumor activity of neocarzinostatin, effect on Rauscher leukemia in mice

Neocarzinostatin (NCS), an antibiotic with a high molecular weight, showed an inhibittory effect on Rauscher mouse leukemia. In normal mice, no significant changes were found in peri· pheral blood pictures except a tendency of lymphocytopenia, when O. 05mg/kg/day and O.50mg/kg/day of NCS were injected intraperi. toneally to two groups of mice for three days. On the other hand, peripheral nucleated cells of Rauscher leukemic mice decreased after intraperitoneal administration of NCS in a dose over O.25mg/kg/day for three days. The cells affected by NCS were mainly erythroblasts and smudged cells. Spleens of Rauscher leukemic mice treated with NCS have been reduced in weight, and histological examinations of livers showed a signicant decrease of infiltrating cells. In three groups treated with 0.25mg/kg/day of NCS for seven days, O.25mg/kg/day for three days and O.50mg/kg/day for three days, the.5()% survival time was longer than in the control group. Particularly, the 50% survival time in Rauscher leukemic mice treated with 0.50 mg/kg/day for three days was over twice that of the control group.</p