THE OCCURRENCE AND DISTRIBUTION OF SALMONELLA TYPES IN FOWL: II. STUDIES OF ARTIFICIAL S. BAREILLY AND S. ORANIENBURG INFECTIONS IN HENS

1947 ◽  
Vol 25f (6) ◽  
pp. 316-325
Author(s):  
F. E. Chase
Keyword(s):  
Egg Production ◽  
Intestinal Tract ◽  
Experimental Studies ◽  
Similar Nature ◽  
Development Of Resistance ◽  
Oral Inoculation

Experimental studies carried out on a limited number of hens infected orally with S. bareilly indicated that occasionally such hens may lay contaminated eggs. Using the estimated numbers of S. bareilly in the feces as the criterion of infection, considerable variation in susceptibility was evident, the carrier period ranging from 5 to 40 days. The organisms were recovered from the intestinal tract and in one instance from the spleen. The apparent development of resistance to repeated oral inoculation was demonstrated. Experiments of a similar nature were made with hens infected orally with S. oranienburg. No contaminated eggs were found, though in this case low egg production resulting from some of the hens moulting reduces the significance of this finding. Fecal counts were lower than those obtained from the S. bareilly infected hens. S. bonariensis was isolated from the feces of two hens during this experiment.

scholarly journals EXPERIMENTAL STUDIES ON THE ADMINISTRATION OF SALVARSAN BY MOUTH TO ANIMALS AND MAN

1912 ◽  
Vol 15 (5) ◽  
pp. 498-509 ◽  
Author(s):  
John A. Kolmer ◽  
Jay Frank Schamberg
Keyword(s):  
Therapeutic Effect ◽  
Intestinal Tract ◽  
Experimental Studies ◽  
Patient Case ◽  
Cutaneous Manifestations ◽  
Full Dose ◽  
Loss Of Weight ◽  
Small Doses ◽  
Gastro Intestinal Tract ◽  
Arsenical Poisoning

Salvarsan in capsule and in solution in doses varying from 0.1 to 0.6 of a gram was administered by mouth to seven patients suffering from syphilis. Five patients were given full doses of 0.6 of a gram. One patient (case 3) received in the aggregate within four weeks 2.4 grams without loss of weight or any disturbing effects. An ulcerating gumma of the knee was practically healed after a period of five weeks. This was the only patient of the seven, however, in whom notable improvement in the cutaneous manifestations followed the administration of the drug. This ulceration would probably have healed as soon, or possibly sooner, under the influence of mercury and the iodids. From the above observations, it would appear that salvarsan administered by mouth up to the full dose of 0.6 of a gram, has a perceptible though feeble therapeutic effect on cutaneous syphilitic manifestations. We should naturally expect the influence of any drug to be more evident in the case of a gumma, in which spirochætes are only sparsely present, than in the secondary syphilides in which the spirochætes are present in enormous numbers. Cutaneous gummata are readily healed at times by very small doses of mercury or iodids. It is interesting to note that the administration of the full dose of the drug by mouth does not appear to give rise to symptoms of systemic arsenical poisoning, unless the vomiting and diarrhea be regarded as such. After some of the full dose administrations, there was neither vomiting nor diarrhea. As salvarsan contains 34 per cent. of arsenic, these patients received the equivalent of five grains of arsenic. In case 3, in the course of four weeks the patient took by mouth the equivalent of over twelve grains of arsenic, without vomiting or having diarrhea, and with no loss of weight or disturbance of health. The urine of this patient was entirely normal. It would seem, therefore, that salvarsan is not converted in the gastro-intestinal tract into an organotropic arsenical compound, and it is possible that it may remain practically unchanged.

RNA N-6-methyladenosine enzymes and resistance of cancer cells to chemotherapy and radiotherapy

Epigenomics ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 801-809 ◽  
Author(s):  
Meiyi Xiang ◽  
Wensu Liu ◽  
Wei Tian ◽  
Abin You ◽  
Dajun Deng
Keyword(s):  
Drug Resistance ◽  
Cancer Cells ◽  
Environmental Changes ◽  
Experimental Studies ◽  
Rna Modification ◽  
Rna Modifications ◽  
Resistance Development ◽  
Development Of Resistance ◽  
Promising Target ◽  
Adaptive Mechanisms

Aim: As one of the early adaptive mechanisms by which cells respond to environmental changes, RNA modification appears to be a very promising target for cancer treatment. Results: RNA modifications are currently a hot topic in epigenetic research. Emerging experimental studies show that expression alterations of multiple m6A enzymes, including demethylase FTO, methyltransferase METTL3 and WTAP, mediate the development of resistance of cancer cells to various treatments. A set of small molecular chemical drugs targeted to these m6A enzymes are under development. Intervention of RNA m6A methylation is a possible therapeutic strategy to overcome drug resistance. Conclusions: RNA m6A methylation may play a crucial role in drug resistance development and intervention in cancer cells.

scholarly journals Candida glabrata colonizes but does not often disseminate from the mouse caecum

2007 ◽  
Vol 56 (5) ◽  
pp. 688-693 ◽  
Author(s):  
Carol L. Wells ◽  
Mary-Alice Johnson ◽  
Michelle J. Henry-Stanley ◽  
Catherine M. Bendel
Keyword(s):  
Candida Albicans ◽  
Candida Glabrata ◽  
Intestinal Tract ◽  
Systemic Candidiasis ◽  
Intestinal Microbes ◽  
Oral Inoculation ◽  
Mouse Intestine ◽  
High Doses ◽  
Clinical Conditions ◽  
Portal Of Entry

Candida glabrata is the second or third most frequent cause of candidaemia. The gastrointestinal tract is considered to be a major portal of entry for systemic candidiasis, but relatively few studies have investigated the pathogenesis of C. glabrata. Experiments were designed to clarify the ability of C. glabrata to disseminate from the mouse intestinal tract. Following oral inoculation, C. glabrata readily colonized the caeca [approx. 107 cells (g caecum)−1] of antibiotic-treated mice, but extraintestinal dissemination was not detected. Superimposing several mouse models of trauma and/or immunosuppression known to induce dissemination of Candida albicans and other intestinal microbes did not cause C. glabrata to disseminate often, although one exception was mice given high doses of dexamethasone for 4 days. These data support the hypothesis that the antibiotic-treated mouse intestine may be an epidemiological reservoir for C. glabrata and that this yeast tends to disseminate under specific clinical conditions.

scholarly journals Efficacy of a novel topical combination of esafoxolaner, eprinomectin and praziquantel against adult cat flea Ctenocephalides felis and flea egg production in cats

Parasite ◽  
2021 ◽  
Vol 28 ◽  
pp. 21 ◽  
Author(s):  
Eric Tielemans ◽  
Prescillia Buellet ◽  
David Young ◽  
Alta Viljoen ◽  
Julian Liebenberg ◽  
...  
Keyword(s):  
Egg Production ◽  
Experimental Studies ◽  
Ctenocephalides Felis ◽  
Control Group ◽  
Placebo Control ◽  
Immature Stages ◽  
The Novel ◽  
Cat Flea ◽  
Larval Hatching ◽  
Adult Cat

Esafoxolaner, a purified enantiomer of afoxolaner with insecticidal and acaricidal properties, is combined with eprinomectin and praziquantel in NexGard® Combo, a novel topical endectoparasiticide formulation for cats. The efficacy of this novel formulation against adult and immature stages of Ctenocephalides felis fleas was tested in four experimental studies. Two studies were designed to test adulticide efficacy, one to test inhibition of immature stages, and one to test both adulticide efficacy and inhibition of immature stages. In each study, cats were randomly allocated to a placebo control group or to a novel formulation group treated once at the minimum recommended dose. Cats were experimentally infested weekly for one to two months with unfed C. felis originating from North America or Europe. For adulticide efficacy evaluations, live fleas were counted 24 h after treatment and after subsequent weekly infestations. For immature stages, flea eggs were collected and counted weekly for evaluation of egg production inhibition and incubated for larval hatching evaluation. In the three studies testing adult fleas, curative efficacies, 24 h after treatment, were 92.1%, 98.3% and 99.7%; preventive weekly efficacies, 24 h after weekly infestations, remained higher than 95.5% for at least one month. In the two studies testing immature stages, egg production and larval hatching was significantly reduced for at least one month. These studies provide robust evidence of efficacy of the novel formulation against experimental adult flea infestations and for the prevention of environmental contamination by immature flea stages, for at least one month.

scholarly journals The Sequential Tissue Distribution of Duck Tembusu Virus in Adult Ducks

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Li Wu ◽  
Jinxiong Liu ◽  
Pucheng Chen ◽  
Yongping Jiang ◽  
Leilei Ding ◽  
...  
Keyword(s):  
Tissue Distribution ◽  
Egg Production ◽  
Intestinal Tract ◽  
Bursa Of Fabricius ◽  
Male And Female ◽  
Southeast China ◽  
Duck Tembusu Virus ◽  
Tembusu Virus ◽  
Systemic Infections ◽  
Kinetics Of

In 2010, a novel Tembusu virus (TMUV) that caused a severe decrease in the egg production of ducks was isolated in southeast China. Given the novelty of this duck pathogen, little information is available regarding its pathogenesis. Here, we systematically investigated the replication kinetics of TMUV PTD2010 in adult male and female ducks. We found that PTD2010 was detectable in most of the parenchymatous organs as well as the oviduct and intestinal tract from days 1 to 7 after inoculation. Viral titers were maintained at high levels for at least 9 days in the spleen, kidney, bursa of Fabricius, brain, and ovary. No virus was detected in any of these organs or tissues at 18 days after inoculation. PTD2010, thus, causes systemic infections in male and female ducks; its replication kinetics show similar patterns in most organs, with the exception of the ovaries and testes.

Experimental Studies of the Motility of the Gastro-intestinal Tract of Rachitic Rats by Means of the X-ray

Radiology ◽  
1930 ◽  
Vol 15 (1) ◽  
pp. 123-128 ◽  
Author(s):  
Leon J. Menville ◽  
S. N. Blackberg ◽  
J. N. Ané
Keyword(s):  
Intestinal Tract ◽  
Experimental Studies ◽  
X Ray ◽  
Gastro Intestinal Tract

Eimeria tenella: experimental studies on the development of resistance to amprolium, clopidol and methyl benzoquate

Parasitology ◽  
1978 ◽  
Vol 76 (2) ◽  
pp. 177-183 ◽  
Author(s):  
H. D. Chapman
Keyword(s):  
Drug Sensitivity ◽  
Experimental Studies ◽  
Eimeria Tenella ◽  
Single Step ◽  
Development Of Resistance ◽  
Fold Reduction ◽  
Resistant Lines ◽  
High Level ◽  
Level Resistance

SummaryThe development of resistance by the Houghton strain of Eimeria tenella to the anticoccidial drugs amprolium, clopidol and methyl benzoquate has been studied. Resistance to amprolium and clopidol developed more readily in experiments where a large number of coccidia were exposed to the drug, either by increasing the number of oocysts in the inoculum or by increasing the number of birds in the group. When 45 birds were given 2·0 × 106 oocysts, resistance to amprolium and clopidol appeared after 6 and 7 passages respectively. In previous experiments, under similar conditions, resistance to robenidine developed after 6 passages, suggesting little difference between these three drugs. Resistance to amprolium and clopidol arose gradually as the concentration of drug was increased, but resistance to methyl benzoquate appeared in a single step from sensitivity to high-level resistance. Both amprolium and clopidol-resistant lines showed an 8-fold reduction in drug sensitivity. Attempts to measure the degree of resistance by calculation of the ED50 were unsuccessful.

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