Activity of quinfamide against natural infections of Entamoeba criceti in hamsters: a new potent agent for intestinal amoebiasis

Parasitology ◽  
1980 ◽  
Vol 81 (1) ◽  
pp. 157-168 ◽  
Author(s):  
R. G. Slighter ◽  
A. Yarinsky ◽  
H. P. Drobeck ◽  
D. M. Bailey
Keyword(s):  
Single Dose ◽  
Adverse Effects ◽  
Total Dose ◽  
Statistical Significance ◽  
Parent Compound ◽  
The Other ◽  
Daily Administration ◽  
Intestinal Amoebiasis ◽  
Tissue Changes

SUMMARYA novel tetrahydroquinolinyl ester, quinfamide, administered orally in multiple doses for 3 days had an ED50, of 0·25 mg/kg/day (total dose 0·75 mg/kg) for eradicating Entamoeba criceti in hamsters in several tests. It was significantly more active by direct comparison than 3 commercially available amoebicides and at least as active as 2 other esters of the parent compound, 1-(dichloroacetyl)-1,2,3,4-tetrahydro-6-quinonnol. After administration of a single dose, ED50, calculations for quinfamide averaged 0·9 mg/kg. Quinfamide was considerably more active than the other tetrahydroquinolinols, diloxanide furoate and teclozan, and it was approximately 1·5 times more active than etofamide; a statistical significance between the latter 2 drugs could be demonstrated in one of 4 tests. Administered prophylactically, quinfamide was shown to protect hamsters from re-infection with E. criceti. It also inhibited propagation of E. histolytica in vitro at a concentration of 20 /tg/ml. No adverse effects were noted in rodents after a single dose as high as 10 g/kg. Daily administration to monkeys of doses up to 500 mg/kg for as long as 37 days produced no pharmacological aberrations during or after medication; haematological studies and urine analyses were normal and no gross or microscopical tissue changes attributable to quinfamide were observed. No toxicity was revealed following acute (2 g/kg) and chronic (500 mg/kg/day × 31 days) administration of the drug to dogs and rats, respectively.

Nonclinical Safety Assessment of Intravenous Optison®: A Perfluoropropane (PFP)-Filled Albumin Microspheres Contrast Agent for Ultrasonography

1998 ◽  
Vol 17 (6) ◽  
pp. 631-662 ◽  
Author(s):  
Yigal Greener ◽  
Anne L. Killam ◽  
Stephen T. Cornell ◽  
Merrill R. Osheroff ◽  
Suzanne T. Wolford
Keyword(s):  
Single Dose ◽  
Adverse Effects ◽  
Contrast Agent ◽  
Safety Assessment ◽  
Blood Compatibility ◽  
Safety Margin ◽  
Product Regulatory ◽  
Genetic Toxicology ◽  
Clinical Safety

OPTISON (FS069), an ultrasonic diagnostic contrast agent, is a suspension of perfluoropropane (PFP)-filled album in microspheres of 2.0-4.5 microns average diameter and 5.0-8.O x 108 microspheresl ml. The following non clinical safety assessment studies in support of product regulatory submissions were conducted: genetic toxicology, single dose (rat, dog, monkey) and repeated (rat, dog) dose toxicology studies, hemodynamics, rabbit irritation, and in vitro blood compatibility. Dosages used throughout the studies were: 0.25, 5.0, 10, 20, or 25 ml/kg. OPTISON was nongenotoxic and nonirritant, and was compatible with human blood. It did not elicit adverse effects in single-dose studies at dosages of up to (and including) 20 ml/ kg. Initial studies conducted in rats and dogs with OPTISON repeated administration, 3 times per week for 3 weeks, showed no adverse effects in dogs to 20 ml/ kg and rats to 5 ml/kg. Mortality and adverse effects were noted in rats at dosages of 20 and 10 ml/ kg and were associated with acute pulmonary congestion. Subsequent repeated administrations for 29 and 31 consecutive days in rats and dogs, respectively, at 10 ml/kg, were not associated with adverse events, except for those which resulted from the anticipated immunogenic response to the IV administration of OPTISON human albumin-based microspheres. No changes in hemodynamic parameters attributable to OPTISON were reported at a dosage of 0.25 ml/ kg in dogs. It is, therefore, concluded that the intravenous administration of OPTISON, at dosages and dose regimens used in these studies, provides a large safety margin for the clinical efficacious dose for diagnostic ultrasound imaging.

Experimental Analysis of the Quality of Needle-Assisted Fenestration in Aortic Stent-Grafts and the Differences Between Gradual and Rapid Balloon Dilation

2020 ◽  
pp. 152660282094709 ◽  
Author(s):  
Dong-lin Li ◽  
Qing-long Zeng ◽  
Yi-lang Xiang ◽  
Chen-yang Qiu ◽  
Zhen-jiang Li ◽  
...  
Keyword(s):  
Statistical Significance ◽  
Balloon Dilation ◽  
The Other ◽  
Maximum Diameter ◽  
Stent Grafts ◽  
Large Balloon Dilation ◽  
Length And Area ◽  
Fabric Tears

Purpose: To report the findings of an in vitro experiment to evaluate the quality of needle fenestrations dilated by different size balloons in various stent-grafts and to investigate the differences between gradual and rapid dilation. Materials and Methods: Fenestrations were made using an 18-G needle in 5 different polyester or expanded polytetrafluoroethylene (ePTFE) stent-grafts: Relay, Valiant, Hercules, TAG, and Ankura. Each stent-graft received 2 groups of fenestrations: one was followed by gradual sequential dilation (4-, 6-, 8-, and 10-mm balloons) and the other by rapid dilation (4- and 10-mm balloons). The pressure was increased to 10 atmospheres or until the balloon was fully inflated with no waist. Quantitative and qualitative evaluations, including fenestration diameter, area, shape, and margins were conducted using light microscopy and scanning electron microscopy. Results: Relay had the strongest resistance to dilation and Ankura the slightest. The maximum length and area of holes expanded as the balloon diameter increased. The fenestrations in polyester devices were mostly elliptical or slit-like, with limited tears but extensive fibers visible in the margin, while ePTFE stent-grafts showed larger fenestration areas with clearer margins. Ankura showed the best quality of fenestrations, which were always circular or square without fabric tears, while the holes in the TAG were square or elliptical but sometimes had a slit after large balloon dilation (≥6 mm). The Relay, Valiant, Hercules, and Ankura devices showed no difference in maximum diameter, fenestration area, or scores of shape and margin (p>0.05). Rapid dilation in the TAG increased the rate of uncontrolled fabric tear, resulting in a larger final diameter (12.90 vs 10.82 mm, p=0.047), smaller area (30.46 vs 41.09 mm2, p=0.028), worse shape (0.75 vs 1.20, p=0.268), and worse margin (0.40 vs 1.00, p=0.174). Though the decreased fenestration shape and margin scores did not reach statistical significance, the trend for decline was more obvious than with the other devices. Conclusion: Materials and structures of the stent-grafts determine the quality of fenestrations dilated by different size balloons. The use of sequential vs rapid balloon dilation is also crucial for fashioning high-quality fenestrations and should be selected judiciously.

scholarly journals In Vitro Evaluation of Desensitizing Agents Containing Bioactive Scaffolds of Nanofibers on Dentin Remineralization

Materials ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1056
Author(s):  
Natália Bastos-Bitencourt ◽  
Marilia Velo ◽  
Tatiana Nascimento ◽  
Cassiana Scotti ◽  
Maria Gardennia da Fonseca ◽  
...  
Keyword(s):  
Statistical Significance ◽  
The Other ◽  
Fluoride Varnish ◽  
Confocal Laser ◽  
Dentinal Tubules ◽  
Bioactive Scaffolds ◽  
Dentin Permeability ◽  
Desensitizing Agents ◽  
Acid Challenge

This study evaluated the effect of the incorporation of bioactive nanofibers in desensitizing agents on dentin permeability. Sixty disks of dentin were randomly distributed in four groups (n = 15). Distribution was based on the desensitizing agents, fluoride varnish and self-etching adhesive, and the presence of nanofibers: C (self-etching adhesive Clearfil SE Bond), CN (Clearfil SE Bond with 1% nanofiber), D (Duraphat varnish), and DN (Duraphat varnish with 1% nanofiber). Dentin permeability was determined using hydraulic conductivity. For a qualitative analysis, confocal laser microscopy and scanning electron microscopy were performed. The C group showed the lowest hydraulic conductance (Lp%) (89.33), while the DN group showed the highest Lp% (116.06). No statistical significance was observed in the Lp% values in all groups after the treatment and 6% citric acid challenge (p > 0.239). In the images, the CN group presented a higher superficial and intratubular deposition. In addition, this group presented a more homogeneous dentin surface and wide occlusion of dentinal tubules than the other treatments. Despite there being no statistical differences among the treatments employed, the images showed that the CN group presented a higher surface and intratubular deposition compared to the other treatments, even after the acid challenge.

scholarly journals In Vitro comparison of cyclic fatigue resistance of TruNatomy in single and double curvature canals compared with different nickel-titanium rotary instruments

2019 ◽  
Author(s):  
Amr M. Elnaghy ◽  
Shaymaa E Elsaka ◽  
Ayman Mandorah
Keyword(s):  
Fatigue Resistance ◽  
Statistical Significance ◽  
Cyclic Fatigue ◽  
The Other ◽  
Probability Of Survival ◽  
Double Curvature ◽  
Significant Difference ◽  
Vortex Blue ◽  
Number Of Cycles

Abstract Background The purpose of this study was to compare the cyclic fatigue resistance of newly developed TruNatomy instruments (TRN) in single and double (S-shaped) curvature canals with HyFlex CM (HCM), Vortex Blue (VB) and RaCe (RC) instruments.Methods Size 20/0.04 taper and size 25/0.04 of HCM, VB and RC were used. For TRN instruments, size 20/0.04 taper (small) and size 26/0.04 taper (prime) were used. The instruments were tested in artificial canals with double curvature (coronal curve; 60° curvature, 5 mm radius and apical curve; 70° curvature and 2 mm radius) and single curvature (60° curvature, 5 mm radius). The number of cycles to failure (NCF) was recorded. Data were statistically analyzed and Weibull analysis was performed on NCF data. Statistical significance was set at p < 0.05.Results TRN and HCM revealed significantly higher NCF compared with the other instruments for both tested sizes in single and double curvature canals ( p < 0.05). TRN and HCM showed no significant difference in the NCF ( p > 0.05). The probability of survival was higher for HCM and TRN instruments than VB and RC instruments.Conclusion HCM and TRN instruments were more resistance to cyclic fatigue than VR and RC instruments in single and double curvature canals. HCM and TRN instruments were anticipated to survive with higher number of cycles than the other tested instruments. RC instrument had the lowest fatigue resistance than the other instruments.

scholarly journals Nitroglycerin for Management of Retained Placenta: A Multicenter Study

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Maria Bullarbo ◽  
Hans Bokström ◽  
Håkan Lilja ◽  
Elisabeth Almström ◽  
Nina Lassenius ◽  
...  
Keyword(s):  
Placebo Group ◽  
Adverse Effects ◽  
Clinical Experience ◽  
Statistical Significance ◽  
Clinical Importance ◽  
The Other ◽  
Retained Placenta ◽  
Sequential Administration ◽  
The Difference ◽  
To Receive

The primary aim was to determine if sequential administration of oxytocin and nitroglycerin is effective for management of retained placenta when performed by obstetricians with no experience of the method. Secondary aims were to examine possible adverse effects of nitroglycerin. One hundred and five women with retained placenta were randomly selected to receive either 1 mg nitroglycerin or placebo tablets sublingually if intravenous oxytocin had failed to expel the placenta. At two of the hospitals some of the midwives were familiar with the use of nitroglycerin. The other midwives and all the participating obstetricians had no clinical experience of the method. In the treatment group, detachment of placenta following nitroglycerin occurred in 37.3% of the women compared to 20.4% in the placebo group (P=0.056). In the two hospitals with some experience of the method, placenta was removed in 9 of 19 (47.4%) women in the nitroglycerin group compared to 3 of 17 (15.0%) women in the placebo group. No adverse effects of clinical importance were registered. Although the difference between the two groups did not reach statistical significance, the higher success rate in the two hospitals with some experience could indicate that clinical experience is of importance in order to achieve placental detachment.

scholarly journals The anti-bacterial efficacy of plant extracts against Enterococcus faecalis

2019 ◽  
pp. 20-25
Author(s):  
Akhila B ◽  
George MK Mallela ◽  
Mettu Shanthan ◽  
Srinivas Nallanchakrav
Keyword(s):  
Adverse Effects ◽  
Root Canal ◽  
Statistical Significance ◽  
The Other ◽  
Ocimum Sanctum ◽  
Research Needs ◽  
Canal System ◽  
Root Canals ◽  
Root Canal Irrigants ◽  
Root Canal System

Brief Background: The main requisites for an endodontic treatment to succeed are adequate cleaning and shaping of the root canals. Several conventional root canal irrigants are in use to decrease the number of microbes in the root canal system. Enterococci are the most frequently isolated organisms in failed root canals. Aim: To compare the anti-bacterial efficacy of herbal root canal irrigating solutions with conventional irrigants. Materials and Methods: The test solutions and tooth samples were prepared. The sectioned tooth samples were inoculated in the bacteria, incubated for 24 hours and biofilm collected. Another sample of biofilm was collected after delivering of the irrigating solutions. Bothe the biofilm samples were checked for the reduction in the bacterial growth. Results: The present study was conducted to evaluate the anti-microbial efficacy of herbal irrigating solutions and compare them with the conventional irrigating solutions. Chlorhexidine (CHX), Ocimum sanctum (OS) and Sodium hypochlorite (NaOCl) showed no statistical significance whereas the other intergroup differences were statistically significant. Summary and Conclusion: OS showed a similar anti-bacterial efficacy to CHX and NaOCl, however, further research needs to be conducted in the area. The use of herbal alternatives may prove to be advantageous given the several unfavourable adverse effects of NaOCl and CHX. Key Words: Antibacterial, Chlorhexidine, Herbal irrigants, Ocimum, Root canal irrigants.

Enhancement of ADP-induced Platelet Aggregation by Adrenaline in Vivo and Its Prevention

1973 ◽  
Vol 29 (02) ◽  
pp. 490-498 ◽  
Author(s):  
Hiroh Yamazaki ◽  
Itsuro Kobayashi ◽  
Tadahiro Sano ◽  
Takio Shimamoto
Keyword(s):  
Platelet Count ◽  
Platelet Aggregation ◽  
Platelet Rich Plasma ◽  
The Other ◽  
Endothelial Surface ◽  
Important Interaction ◽  
Blood Coagulability ◽  
The Difference

SummaryThe authors previously reported a transient decrease in adhesive platelet count and an enhancement of blood coagulability after administration of a small amount of adrenaline (0.1-1 µg per Kg, i. v.) in man and rabbit. In such circumstances, the sensitivity of platelets to aggregation induced by ADP was studied by an optical density method. Five minutes after i. v. injection of 1 µg per Kg of adrenaline in 10 rabbits, intensity of platelet aggregation increased to 115.1 ± 4.9% (mean ± S. E.) by 10∼5 molar, 121.8 ± 7.8% by 3 × 10-6 molar and 129.4 ± 12.8% of the value before the injection by 10”6 molar ADP. The difference was statistically significant (P<0.01-0.05). The above change was not observed in each group of rabbits injected with saline, 1 µg per Kg of 1-noradrenaline or 0.1 and 10 µg per Kg of adrenaline. Also, it was prevented by oral administration of 10 mg per Kg of phenoxybenzamine or propranolol or aspirin or pyridinolcarbamate 3 hours before the challenge. On the other hand, the enhancement of ADP-induced platelet aggregation was not observed in vitro, when 10-5 or 3 × 10-6 molar and 129.4 ± 12.8% of the value before 10∼6 molar ADP was added to citrated platelet rich plasma (CPRP) of rabbit after incubation at 37°C for 30 second with 0.01, 0.1, 1, 10 or 100 µg per ml of adrenaline or noradrenaline. These results suggest an important interaction between endothelial surface and platelets in connection with the enhancement of ADP-induced platelet aggregation by adrenaline in vivo.

ALDOSTERONE STIMULATION IN VITRO

1965 ◽  
Vol 50 (2) ◽  
pp. 301-309 ◽  
Author(s):  
Jürg Müller
Keyword(s):  
Ammonium Chloride ◽  
Human Urine ◽  
Incubation Medium ◽  
The Other ◽  
Ammonium Ions ◽  
Response Curves ◽  
Urine Extract ◽  
Similar Dose ◽  
Aldosterone Production

ABSTRACT An extract of human urine, which was previously shown to stimulate aldosterone production by rat adrenal sections, was further purified. Evidence was obtained that its aldosterone-stimulating effect was due to the presence of ammonium ions. Addition of ammonium chloride and of urine extract to the incubation medium caused identical increases in aldosterone production in vitro. In addition to ammonium ions, rubidium and caesium ions also stimulated aldosterone production up to 250% that of control values without a significant effect on corticosterone production. Similar dose-response curves were obtained when increasing concentrations of potassium, ammonium, rubidium and caesium ions were tested. Aldosterone production was maximal at concentrations of 7 mval/1 and was significantly lower at higher concentrations. When ammonium chloride and ACTH were simultaneously added to the incubation medium, the production of aldosterone and of corticosterone was lower than with ACTH alone. On the other hand, the stimulating activity on aldosterone and corticosterone production by »TPN« (NADP) and glucose-6-phosphate was enhanced by the simultaneous addition of ammonium chloride.

EFFECT OF FEEDING ETHINYLOESTRADIOL FOR VARIOUS PERIODS BEFORE MATING ON REPRODUCTION IN THE HAMSTER

1972 ◽  
Vol 70 (3) ◽  
pp. 582-590
Author(s):  
B. K. Davis ◽  
I. Noske ◽  
M. C. Chang
Keyword(s):  
Single Dose ◽  
Pregnancy Rate ◽  
Fertility Control ◽  
Normal Pregnancy ◽  
Oestrous Cycle ◽  
The Other ◽  
Feeding Schedule ◽  
Crown Rump Length ◽  
Essentially Normal ◽  
Effect Of Feeding

ABSTRACT Ethinyloestradiol (EO) fed for various periods before mating to female hamsters affected the timing of mating and pregnancy rate. Slight effects on ovulation, foetal-crown rump length and resorption may have occurred, but effects on implantation were not apparent among pregnant hamsters. The response observed depended upon the feeding schedule adopted: hamsters fed 2.5 mg EO in a single dose, on day 3 before mating, mated normally but had a significantly lower pregnancy rate; on the other hand, animals fed 2.5 mg EO (0.21 mg/day) over three oestrous cycles, days 14–3 before mating, showed variations in the time of mating but had an essentially normal pregnancy rate; and, a group of hamsters who received the same total amount of EO (0.63 mg/day) over one oestrous cycle, days 6–3 premating, showed untowards effects by the steroid on both the timing of mating and pregnancy rate. The implications of these results are considered in relation to fertility control.

EFFECT OF ACTINOMYCIN D ON TSH-INDUCED STIMULATION OF THYROIDAL PROTEIN SYNTHESIS IN THE RAT

1974 ◽  
Vol 77 (1) ◽  
pp. 64-70 ◽  
Author(s):  
Gustav Wägar
Keyword(s):  
Protein Synthesis ◽  
Actinomycin D ◽  
The Other ◽  
Leucine Incorporation ◽  
Short Term ◽  
Other Hand ◽  
Thyroid Glands ◽  
Translational Level ◽  
Stimulation Of

ABSTRACT Whether the short-term regulation of thyroidal protein synthesis by TSH occurs at the transcriptional or the translational level was tested by measuring the effect of actinomycin D (act D) on the TSH-induced stimulation of L-14C-leucine incorporation into the thyroidal proteins of rats. TSH was injected 6 h before the rats were killed. The thyroid glands were then removed and incubated in vitro in the presence of L-14C-leucine for 2 h. The pronounced stimulation of leucine incorporation in the TSH-treated animals was depressed as compared with controls but still significant even when the animals had been pre-treated with 100 μg act D 24 and 7 h before sacrifice. On the other hand, act D strongly decreased incorporation of 3H-uridine into RNA. Short-term regulation of thyroidal protein synthesis by TSH appears to be partly but not wholly dependent on neosynthesis of RNA. Hence regulation may partly occur at the translation level of protein synthesis.

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