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Background Bio-Oss® collagen (BC) has been used in clinical applications for years but the ridge preservation property of BC remains controversial. There is no animal model accurately simulates the extraction socket in people. The aim of this study was to assess the ridge preservation of a novel extraction sockets with a thin buccal plate using BC. Materials and methods Two beagle dogs were used to assess the characterization of the novel extraction socket. The width and height of the socket were measured and biopsies of the socket were collected for histologic examination. Four beagle dogs were used to assess the ridge preservation property of BC. BC was placed in the socket and socket left untreated was set as control group (CT). Cone-beam computed tomography analysis, histological examination, and micro-CT analysis were used to evaluate the ridge preservation. Results The novel extraction socket had obvious larger volume with a markedly narrow buccal wall than mandible extraction sockets. At 12 weeks, the width of the crest of the alveolar ridge preservation ratios was 34% for the CT and 82% for the BC. BC group had larger socket volume compare to CT group. BC group had a significant higher bone density in the middle and apical areas of the alveolar bone. Socket placed with BC showed significantly less vertical bone loss compared with CT group. Conclusion Extraction site with a significantly larger dimension and a very thin buccal plate was established. Extraction sockets filled with BC exhibit excellent maintenance of alveolar bone volume.

Highlights • HAD-B1 is used in Korean medicine to treat lung cancer patients. • The acute and Sub-chronic toxicity of HAD-B1 was evaluated in Beagle dogs. • No toxicologically significant effects were found. • The NOAEL was ≥2000 mg/kg/day for both genders, with no target organ effect., HAD-B1 is a herbal formula originated from Korean Traditional Medicine that used to treat lung cancer patients. Herein we assessed acute and sub-chronic toxicity of HAD-B1 in beagle dogs. Acute study, 4 weeks dose rate finding (DRF) study and sub chronic toxicity study for 13 weeks were done by oral administration at doses of 0, 500, 1000, and 2000 mg/kg. Neither oral acute toxicity study nor DRF study showed any significant clinical signs, death, or weight changes. Based on that, a sub-chronic study for 13-weeks was performed. As a result, HAD-B1 caused a decrease of mean daily feed consumption in females, infiltration of intestinal inflammatory cells in both sexes, a significant decrease in total cholesterol (TCHO) in females, Kupffer cell hypertrophy/hyperplasia in the liver as well as dilation of the sinusoid. However, there were no significant toxic effects in the treated group compared to the control group. Therefore, the No Observed Adverse Effect Level (NOAEL) of the HAD-B1 is at least 2000 mg/kg/day when administrated orally for 13 consecutive weeks. These results demonstrate that HAD-B1 consumption is relatively non-toxic and safe for clinical usage.

The main objective of our current study is to develop and validate an accurate and direct ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method to simultaneously detect plasma concentrations of tofacitinib and its metabolite M9, and to study the pharmacokinetic profiles of the two compounds in beagle dogs. After rapid precipitation of protein by adding acetonitrile, the chromatographic separation of tofacitinib was completed, as well as M9 and upadacitinib (internal standard, IS) by using an Acquity BEH C18 (1.7 μm, 2.1 mm × 50 mm) column. A Xevo TQ-S triple quadrupole tandem mass spectrometer was employed to determine their concentrations under the positive ion pattern. Selective reaction monitoring (SRM) was used with ion transitions at m/z 313.12 → 148.97 for tofacitinib, m/z 329.10 → 137.03 for M9, and m/z 380.95 → 255.97 for IS, respectively. This assay demonstrated excellent linearity, and the ranges of calibration curves for both tofacitinib and M9 were 0.5–400 ng/mL. The new UPLC-MS/MS assay can reach the values (0.5 ng/mL) of lower limit of quantification (LLOQ) for both tofacitinib and M9. Both intra-day and inter-day accuracy of all analytes ranged from −12.0% to 14.3%, while the precision was ≤13.2%. The recovery rate of all analytes was >88.5%, and more importantly there was no conspicuous matrix effect. In addition, the stability was consistent with the quantificative requirements of plasma samples under all conditions. Finally, the assay on UPLC-MS/MS is able to be employed to determine the pharmacokinetic characteristics of tofacitinib and its metabolite M9 in the plasma of beagle dogs after taking orally a dose of tofacitinib at 2 mg/kg.

Aim or Purpose The purpose of study was to compare the amounts of mature bone formation between a new bioactive collagen membrane (BCM) and a conventional collagen membrane (CCM) when used in a canine model of dental guided bone and tissue regeneration (GBR). Materials and Methods GBR surgery was performed in 36 skeletally mature (9-14kg / 20-30lb) Beagle dogs using a split mouth design. The implant site was prepared with a titanium implant in the tooth socket and remaining void filled with a granulated bone substitute. The collagen membranes were trimmed and placed over the implant, and the gingiva closed around the treatment site. Animals were sacrificed (n=6 each group) at 4, 8, and 12 weeks after implant placement. Bone formation and tissue reactions were measured by micro-CT and histomorphometry. The study was approved by the institutional Animal Ethics committee. Results Bone volume in sites treated with both collagen membranes was significantly greater than controls at 12 weeks. However, the BCM displayed comparatively more bone formation at the early time point of 4 weeks than the CCM. Further, histological assessment of sites treated with the bioactive membrane revealed that mature cortical bone formation occurred as early as 8 weeks, which was likely due to the minimal inflammatory reaction observed and retention of the bioactive barrier structure. Conclusions The new bioactive collagen membrane induces early mature bone formation in a canine model of dental GBR.

Naoxintong Capsule (NXTC), a standardized herbal medicine, has been widely applied in treating cardiovascular and cerebrovascular diseases with remarkable efficacy. However, the efficacy contributing components of NXTC are unclear, and the in vivo absorption and metabolism processes of NXTC remain largely obscured. In this study, using beagle dog as model species, we have identified and tentatively characterized 25 prototype and 15 catabolites of NXTC in beagle dog plasma by ultra-fast liquid chromatography/quadrupole-time-of-flight tandem mass spectrometry (UFLC-Q-TOF-MS/MS). We have proposed the in vivo bio-transformation pathways of these absorbed constituents. In addition, for six crucial components, we have developed a quantitative method and conducted plasma pharmacokinetic study of these six components by rapid resolution liquid chromatography tandem triple quadrupole mass spectrometry (RRLC-QQQ-MS/MS). In conclude, our study provided comprehensive insights into the understanding of the plasma absorbed components profiling of NXTC as well as their in vivo transformation behaviors, which would be of great value for identifying efficacy contributing critical components as well as mechanism related investigations of NXTC in the future.

Understanding the role of Quantum Chromodynamics in generating nuclear forces is important for uncovering the mechanism of short-ranged nuclear interactions and their manifestation in short range correlations (SRC). The future Electron-Ion-Collider (EIC) at Brookhaven National Laboratory in the US will provide an unprecedented opportunity to systematically investigate the underlying physics of SRC for energies and kinematic regions that are otherwise impossible to reach. We study SRCs in electron-deuteron scattering events using the Monte Carlo event generator BeAGLE. Specifically, we investigate the sensitivity of observables to high internal nucleon momentum in incoherent diffractive $J/\psi$ vector meson production. In a plane wave impulse approximation, the initial state deuteron wavefunction can be accessed directly from the four-momentum of the spectator nucleon. We use realistic physics simulations and far-forward detector simulations of the EIC to fully reveal the physics potential of this exclusive process. In particular, we provide the luminosity and detector requirements necessary to study SRCs in the deuteron at an EIC., Comment: There are a total of 7 figures and 2 tables in the main text, together with an Appendix with supplemental material

Within preclinical research, the pig has become an important model in regulatory toxicology and pharmacokinetics, to assess oral dosage forms and to compare different formulation strategies. In addition, there are emerging application of the pig model to asses clinical dosing conditions in the fasted and fed state. In this study, the gastrointestinal transit conditions in male landrace pigs were studied with a telemetric motility capsule under fasted and postprandial conditions. The whole gut transit time (WGTT) was determined by administering a SmartPill® capsule to four landrace pigs, under both fasted and fed state conditions in a cross-over study design. Overall, this study found that small intestinal transit in landrace pigs ranged from 2.3 – 4.0 h, and was broadly similar to reported human estimates and was not affected by the intake conditions. Gastric emptying was highly variable and prolonged in landrace pigs ranging from 20 – 233 h and up to 264 h in one specific case. Under dynamic conditions pigs have a low gastric pH comparable to humans, however a high variability under fasted conditions could be observed. The comparison of the data from this study with a recent similar study in beagle dogs revealed major differences between gastric maximum pressures observed in landrace pigs and dogs. In the porcine stomach maximum pressures of up to 402 mbar were observed, which are comparable to reported human data. Intestinal maximum pressures in landrace pigs were in the same range as in humans. Overall, the study provides new insights of gastrointestinal conditions in landrace pigs, which can lead to more accurate interpretation of in vivo results obtained of pharmacokinetic studies in preclinical models. While small intestinal transit conditions, GI pH and pressures were similar to humans, the prolonged gastric emptying observed in pigs need to be considered in assessing the suitability of the pig model for assessing in vivo performance of large non-disintegrated oral drug products..

Genotype imputation is commonly performed in genome-wide association studies because it greatly increases the number of markers that can be tested for association with a trait. In general, one should perform genotype imputation using the largest reference panel that is available because the number of accurately imputed variants increases with reference panel size. However, one impediment to using larger reference panels is the increased computational cost of imputation. We present a new genotype imputation method, Beagle 5.0, which greatly reduces the computational cost of imputation from large reference panels. We compare Beagle 5.0 with Beagle 4.1, Impute4, Minimac3, and Minimac4 using 1000 Genomes Project data, Haplotype Reference Consortium data, and simulated data for 10k, 100k, 1M, and 10M reference samples. All methods produce nearly identical accuracy, but Beagle 5.0 has the lowest computation time and the best scaling of computation time with increasing reference panel size. For 10k, 100k, 1M, and 10M reference samples and 1,000 phased target samples, Beagle 5.0's computation time is 3× (10k), 12× (100k), 43× (1M), and 533× (10M) faster than the fastest alternative method. Cost data from the Amazon Elastic Compute Cloud show that Beagle 5.0 can perform genome-wide imputation from 10M reference samples into 1,000 phased target samples at a cost of less than one US cent per sample.

Transcranial magnetic motor evoked potentials (TMMEPs) can assess the functional integrity of the spinal cord descending motor pathways. In intervertebral disc herniation (IVDH), these pathways are compromised to varying degrees reflected by the severity of neurological deficits. The hypotheses of this study were as follows: (1) TMMEPs differ in dogs with IVDH and healthy control dogs; (2) TMMEPs reflect different severities of neurological signs; and (3) TMMEPs can document functional motor improvement and therefore monitor recovery of function. TMMEPs were recorded in 50 dogs with thoracolumbar IVDH. Clinical signs ranged from spinal hyperesthesia to non-ambulatory paraparesis in 19 dogs and paraplegia with/without deep pain sensation in 31 dogs. In these 31 paraplegic dogs, transcranial magnetic stimulation (TMS) was repeated during follow-up examinations. Ten healthy Beagle dogs served as controls. There was a significant increase in onset latency and decrease in peak-to-peak amplitude in the pelvic limb TMMEPs of dogs with spinal hyperesthesia to severe paraparesis compared to control dogs. Waveforms in dogs with IVDH were predominantly polyphasic in contrast to the biphasic waveforms of the control dogs. TMMEPs could not be generated in the pelvic limbs of paraplegic dogs. However, TMMEPs with markedly increased onset latencies and decreased peak-to-peak amplitudes reappeared in the pelvic limbs of dogs that were paraplegic before surgery and showed functional motor improvement during follow-up. The severity of neurological deficits was reflected by TMMEP findings, which could be used to document functional motor recovery in IVDH. TMS could therefore be used as an ancillary test to monitor response to therapy in dogs during rehabilitation.

Imputation of high-density genotypes from low- or medium-density platforms is a promising way to enhance the efficiency of whole-genome selection programs at low cost. In this study, we compared the efficiency of three widely used imputation algorithms (fastPHASE, BEAGLE and findhap) using Chinese Holstein cattle with Illumina BovineSNP50 genotypes. A total of 2108 cattle were randomly divided into a reference population and a test population to evaluate the influence of the reference population size. Three bovine chromosomes, BTA1, 16 and 28, were used to represent large, medium and small chromosome size, respectively. We simulated different scenarios by randomly masking 20%, 40%, 80% and 95% single-nucleotide polymorphisms (SNPs) on each chromosome in the test population to mimic different SNP density panels. Illumina Bovine3K and Illumina BovineLD (6909 SNPs) information was also used. We found that the three methods showed comparable accuracy when the proportion of masked SNPs was low. However, the difference became larger when more SNPs were masked. BEAGLE performed the best and was most robust with imputation accuracies >90% in almost all situations. fastPHASE was affected by the proportion of masked SNPs, especially when the masked SNP rate was high. findhap ran the fastest, whereas its accuracies were lower than those of BEAGLE but higher than those of fastPHASE. In addition, enlarging the reference population improved the imputation accuracy for BEAGLE and findhap, but did not affect fastPHASE. Considering imputation accuracy and computational requirements, BEAGLE has been found to be more reliable for imputing genotypes from low- to high-density genotyping platforms.

The aim of this study was to evaluate the in vivo effect of antibacterial modified dental implants in the first stages of peri-implantitis. Thirty dental implants were inserted in the mandibular premolar sites of 5 beagle dogs. Sites were randomly assigned to Ti (untreated implants, 10 units), Ti_Ag (silver electrodeposition treatment, 10 units), and Ti_TSP (silanization treatment, 10 units). Coated implants were characterized by scanning electron microscopy, interferometry and X-ray photoelectron spectroscopy. Two months after implant insertion, experimental peri-implantitis was initiated by ligature placement. Ligatures were removed 2 months later, and plaque formation was allowed for 2 additional months. Clinical and radiographic analyses were performed during the study. Implant-tissue samples were prepared for micro computed tomography, backscattered scanning electron microscopy, histomorphometric and histological analyses and ion release measurements. X-ray, SEM and histology images showed that vertical bone resorption in treated implants was lower than in the control group (P < 0.05). This effect is likely due to the capacity of the treatments to reduce bacteria colonization on the implant surface. Histological analysis suggested an increase of peri-implant bone formation on silanized implants. However, the short post-ligature period was not enough to detect differences in clinical parameters among implant groups. Within the limits of this study, antibacterial surface treatments have a positive effect against bone resorption induced by peri-implantitis. info:eu-repo/semantics/acceptedVersion

A toxicological study was performed in Beagle dogs treated for 180 days with the product Joao da Costa e Associacoes. Were used six males and six females distributed in control and treated groups (n=3). We used a dose of 566 mg/kg of the product according to preclinical study in rodents. The animals were weighed and evaluated by clinical and laboratory aspects. The product did not cause mortality or alter the normal behavior of animals, but interfered with the weight gain on males in the middle phase of the treatment. The group treated had a lower incidence of clinical abnormalities compared to control, checked by veterinary consultations. Laboratory data showed elevated blood glucose levels perhaps due to the high amount of sucrose present in the product; about the histopathological data no significant change was found. We conclude that the product Joao da Costa and Associacoes, at the dose tested, has low toxicity in Beagle dogs treated chronically.

Background/purpose Poorly crystalline hydroxyapatite was improved so that it has better cell affinity in vitro . We studied the efficacy of a novel resorbable poorly crystalline hydroxyapatite-based biphasic calcium phosphate, BonaGraft, for bone regeneration in vivo . Materials and methods The beagle was used as an animal model, and cylindrical artificial bone defects (3 mm in diameter and 6 mm long) were produced in the alveolar bone. The BonaGraft (ratio of poorly crystalline hydroxyapatite to b-tricalcium phosphate, 60:40) was used to fill in the defect, and unfilled defects served as a control group. At 5, 8 and 10 weeks after the operation, the size of the residual graft and new bone formation were evaluation by a histomorphometric analysis. In a clinical trial, 33 enrolled patients included 15 males and 18 females with ages ranging from 35 to 54 years. The main indications were ridge augmentation ( n = 12), sinus lifting ( n = 2), repair of periodontal disease ( n = 14), and repair of radicular cysts ( n = 5). The clinical outcomes of the surgery were primarily evaluated by clinical radiographs. Results In the animal study, implanting BonaGraft produced greater new-bone formation (74.5% ± 1.0%) at 10 weeks postoperatively than that of the control (40.2% ± 0.3%). BonaGraft particles were gradually resorbed and substituted by bone. The in vivo graft resorption time and bone healing time of 12.1 weeks were mathematically determined by the least squares method. In the clinical test, all patients implanted with BonaGraft reported satisfactory clinical outcomes without major material-related side effects. According to the radiographic pictures, implantation of BonaGraft enhanced bone formation. Conclusion According to the animal study results, BonaGraft has a suitable resorption period and satisfactory outcomes of new bone formation. The clinical study produced high satisfaction with clinical results both objectively and subjectively. For this reason, BonaGraft seems to be an alternative choice for a bone substitute in dental applications.

Studies have shown that the brown dog tick, Rhipicephalus sanguineus sensu lato, when fed on the beagle breed of dog, Canis lupus familiaris, development negatively affected in comparison with tick development after feeding on the English cocker spaniel breed. Thus leading to the suggestion that beagle dogs are be tick-resistant dogs. Behavioural studies have demonstrated that more ticks are attracted by extracts from cocker spaniels than from beagles and that the odour of beagles is a repellent. To test the hypothesis that resistant hosts produce repellent compounds, we undertook comparative chemical analysis on beagle odour and cocker spaniel extracts using coupled high-resolution gas chromatography-mass spectrometry (GC-MS) and also used Petri-dish and olfactometer behavioural assays to assess the response of ticks to identified non-host compounds. The beagle odour extracts contained almost three times as many chemical compounds as cocker spaniel samples. Several non-host compounds were identified, i.e. 2-hexanone, benzaldehyde, nonane, decane and undecane. In Petri-dish assays, 2-hexanone was repellent at 30 min at concentrations of 0.200 and 0.050 mg cm(-2), whilst at 10 min, the 0.100 mg cm(-2) concentration was repellent. Benzaldehyde repelled ticks at 30 min (0.200 mg cm(-2)) and at 5 min (0.050 mg cm(-2)). Undecane was repellent for R. sanguineus s.l. ticks for the first 5 min at the highest concentration tested. Nonane and decane did not show any significant repellency at any concentration or time evaluated. When 2-hexanone and benzaldehyde were combined, an increase in the repellency rate was observed, with activity comparable or better than N,N-diethyl-3-methylbenzamide (DEET). In olfactometer bioassays, a 1:1 mixture of 2-hexanone:benzaldehyde and DEET were repellent for R. sanguineus s.l. adults at the concentration of 0.200 mg cm(-2). This study identified non-host semiochemicals that mediate avoidance of the beagle dog breed by R. sanguineus s.l. This finding may enable development of new approaches to control this tick.

application/pdf, Three beagle dogs were inoculated with mice spleen/liver homogenate infected with Ehrlichia species detected from Ixodes ovatus (EIO) and one dog was used as a control. All three infected dogs did not show clinical signs of disease except for mild pyrexia throughout the 41-day study period. Splenomegaly was observed from Day 7 post-inoculation (p.i.) in two of the dogs. Hematological and biochemical abnormalities included mild thrombocytopenia, hypoproteinaemia, hypoalbuminaemia and increased C-reactive protein values. One of the dogs' splenic aspirate sample was PCR-positive for Ehrlichia Day 7 p.i. and another dogs' blood and bone marrow aspirate sample was PCR-positive Day 41 p.i. Sequence analysis of the PCR products showed 100% homology with the 16SrRNA partial gene sequence of Ehrlichia sp. HF565. Antibody titers to EIO were observed in all three experimentally infected dogs starting from the first week p.i. and cross-reactivity with Ehrlichia canis was detectable in one of the dogs starting Day 7 p.i. These data suggest that infection of dogs with EIO is possible, though is probably of low pathogenic importance. Cross-reactivity of EIO infected dog serum with E. canis raises the likelihood of false E. canis seropositive dogs. (c) 2005 Elsevier B.V. All rights reserved.

Extents of the sparfloxacin (3 – 10 mg/kg, i.v.)-induced QT interval prolongation under normokalemic and hypokalemic conditions were assessed in halothane-anesthetized beagle dogs (n = 5). The hypokalemic condition was induced by an oral administration of furosemide (200 mg/kg per day) for 3 days, which decreased the serum potassium concentration from 3.65 ± 0.13 to 2.35 ± 0.13 mM (P

The aim of this work was to monitor levels of Cd, Cu, Pb, Zn and Fe in sediments, mussels (Mytilus edulis chilensis) and limpets (Nacella magellanica) from the Industrial zone (IZ); fuel dock (FD) and Ushuaia Peninsula (UP) on the Beagle Channel. In sediments, seasonal variations showed high values of Cu and Pb in spring and Zn in autumn. Comparing among sites, Cd concentration was superior in UP (2.07 μg/g); while Pb was maximum in FD (41.00 μg/g). In mussels, a higher bioaccumulation in winter was found. Mussels from UP showed the highest bioaccumulation of Cu (5.95 μg/g) and those from FD presented the highest of Zn (170.15 μg/g). A seasonal trend was not found for limpets, while differences among sites were observed for Cd being the highest at IZ (3.02 μg/g). Although pollution level found was low, anthropic activities at the studied sites could result in deterioration, further monitoring is recommended. © 2012 Elsevier Ltd. Fil: Duarte, Claudia Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Giarratano, Erica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina Fil: Gil, Monica Noemi. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina

Objectives The purposes of this study were to evaluate if (1) Angiostrongylus vasorum -infected dogs recruit pulmonary arteriovenous (AV) shunts attenuating the development of pulmonary hypertension (PH), detectable using saline contrast echocardiography, (2) anthelmintic therapy causes an acute increase in pulmonary arterial pressure (PAP), (3) Tissue Doppler Imaging (TDI) allows detection of mild changes in right ventricular function secondary to pulmonary (vascular) disease. Animals 6 healthy Beagle dogs, each infected with 200 A. vasorum larvae. Methods Conventional, TDI and contrast echocardiography, invasive PAP measurements before (T0), 7–12 weeks post infection (wpi, T1), and 1–5 days post therapy (dpt, T2). Results All dogs had patent infections 7–8 wpi and respiratory signs 6–9 wpi. PAP was mildly but significantly increased at T2. Saline contrast echo was positive in 3/6 dogs at T1 and 4/6 dogs at T2. Pulmonary transit time did not change. Of all numeric echocardiographic parameters, only a non-significant decrease in the E′ wave and inversion of E′/A′ ratio in 3 dogs at T2 could be observed. Two of these had mild PH and negative saline contrast echocardiography. Conclusion A. vasorum infection causes only a mild increase in PAP following inoculation and anthelmintic therapy. The absence of important PH may in part be explained by the recruitment of AV shunts in the presence of vascular obstructive disease. TDI echocardiographic parameters may be more sensitive to detect mild changes in RV function than conventional parameters.

11 páginas, 3 figuras, 5 tablas -- PAGS nros. 5290-5300, The protective capabilities of three Leishmania recombinant proteins – histone 1 (H1) and hydrophilic acylated surface protein B1 (HASPB1) immunized singly, or together as a protein cocktail vaccine with Montanide™, and the polyprotein MML immunized with MPL®-SE adjuvant – were assessed in beagle dogs. Clinical examination of the dogs was carried out periodically under blinded conditions and the condition of the dogs defined as asymptomatic or symptomatic. At the end of the trial, we were able to confirm that following infection with L. infantum promastigotes, five out of eight dogs immunized with H1 Montanide™, and four out of eight dogs immunized with either the combination of HASPB1 with Montanide™ or the combination of H1 + HASPB1 with Montanide™, remained free of clinical signs, compared with two out of seven dogs immunized with the polyprotein MML and adjuvant MPL®-SE, and two out of eight dogs in the control group. The results demonstrate that HASPB1 and H1 antigens in combination with Montanide™ were able to induce partial protection against canine leishmaniasis, even under extreme experimental challenge conditions, This work was supported by RMF Dictagene, Lausanne Switzerland, Novartis Animal Vaccines Ltd. (Braintree, UK) and the FNRS grant no. 31003-103813 to NF. J. Moreno holds a “Ramon y Cajal” contract from MEC, C. Chicharro holds a contract from ISCIII (TRPY1013/04) I. Cruz holds a contract from RICET-FIS, E. Carrillo was supported by a FPI fellowship from MEC

Abstract—Project Sedan, the first nuclear excavation experiment in the Plowshire Program, was conducted on July 6, 1962. A thermonuclear device of approximately 100-kton yield was detonated at a depth of 625 ft. The amount of radioactive material released to the atmosphere was less than that normally produced by a 2-kton surface explosion. One of the studies made in connection with this project was conducted by the U.S. Public Health Service under sponsorship of the U.S. Atomic Energy Commission. It was designed to measure the radioiodine isotopes inhaled and metabolized by Beagle dogs at distances up to 40 miles from ground zero (GZ). The objective of the study was to obtain some correlation between the air concentrations of radioiodine isotopes, as measured by field type physical sampling apparatus, and the concentration in an animal exposed only via the pulmonary route. Thirty Beagle dogs were exposed to the fallout cloud produced by the detonation of this device. The selectivity of the thyroid for iodine made it possible to quantitate the amounts of iodine present in the gland at varying times after exposure. The iodine content of the air during cloud passage was determined by low volume air samplers. Twenty of the animals exposed were located along the center line of the fallout cloud. From the results observed in these animals it would appear that a major portion of the iodine available to an animal from the fresh fission product cloud was rapidly metabolized by the animal, appearing in the thyroid within a very short period of time. In three out of six subjects sacrificed immediately after cloud passage, the thyroid uptake amounted to 100 per cent or more of the total I133 as determined by low-volume air sampler, with an average for all six subjects of 92 per cent uptake. In this field study the maximum amount of radioiodine isotopes in the thyroid occurred the second or third day following exposure. Apparently a build-up of radioiodine isotopes occurred by radioactive decay of fallout particles trapped in the respitory system and digestive tract during cloud passage. Therefore, additional radioiodine isotopes, daughters of fission products, became available for uptake by the thyroid for a period of 2-3 days after the exposure.

The inhibitory effects of cigarette smoke on tracheal ciliary activity have been reported by several authors. Because of the possible consequence of this effect on the toxicity of inhaled particles, preliminary studies were undertaken to determine whether cigarette smoke altered the clearance of particles from the lung. Acute exposures of rats to cigarette smoke did not influence the clearance of 59 Fe 2 O 3 or 51 Cr 2 O 3 particles from the lung. The possible effects of chronic cigarette smoking were examined in beagle dogs smoking 20 cigarettes per day. Deposition of inhaled insoluble particles was tested periodically by exposing the dogs to aerosols of 59 Fe 2 O 3 or 5l Cr 2 O 3 . Subsequent pulmonary clearance was measured by whole-body counting and body-scanning techniques. No effects were seen in dogs after smoking cigarettes five days per week for over a year.