A collagen-based sealant to prevent in vivo reformation of epidural scar adhesions in an adult rat laminectomy model

Object. The authors investigated the effect of a collagen-based sealant, Gel Amidon Oxydé (GAO), in preventing the reformation of epidural scar adhesions in an adult rat model of laminectomy. Methods. Thirty-two adult Sprague—Dawley rats underwent a complete L5–6 laminectomy, after which the dura mater was exposed and the left adjacent L-4 and L-5 nerve roots were exposed. The surgical wound was then closed; 1 month later it was reopened. The epidural scar adhesions that developed were observed and carefully removed, leaving clean dura and nerve roots reexposed. In 16 experimental rats, GAO was placed onto the reexposed dura and around the nerve roots before it polymerized. No treatment was performed in 16 control rats. Postoperatively, all rats were healthy and without neurological deficit. The incisions healed within 1 week regardless of the treatment with the GAO. Three months after reoperation, magnetic resonance imaging revealed that important epidural adhesions were present in the control rats but not in the experimental rats. These findings were then confirmed by gross anatomical examination in which a white tissue layer was found over the dura without adhesions in the experimental animals, whereas significant epidural scar adhesions were demonstrated in the controls. Histological evaluation of the laminectomy site also showed that the peridural space in the experimental rats was larger than that in the controls. Conclusions. The authors found that GAO may be a safe and effective antiscarring adhesion biomaterial in vivo. When placed into the laminectomy site, GAO may prove beneficial in preventing the formation and reformation of epidural scar adhesions in humans.

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Use of a collagen-based sealant to prevent in vivo epidural adhesions in an adult rat laminectomy model

Journal of Neurosurgery Spine ◽

10.3171/spi.2001.94.1.0061 ◽

2001 ◽

Vol 94 (1) ◽

pp. 61-67 ◽

Cited By ~ 7

Author(s):

Song Liu ◽

Jean Pierre Boutrand ◽

Marc Tadie

Keyword(s):

Early Postoperative Period ◽

Sprague Dawley ◽

Nerve Roots ◽

Tissue Layer ◽

Connective Tissue Layer ◽

Content Type ◽

Adult Rat ◽

Muscle Lesions ◽

Fine Print

Object. The authors investigated the effect of a collagen-based sealant, Gel Amidon Oxydé (GAO), in the prevention of epidural scar adhesions in an adult rat model of laminectomy. Methods. Seventy-two adult Sprague—Dawley rats underwent an L5–6 laminectomy, after which the dura mater and the left L-4 and L-5 nerve roots were exposed. In the 36 animals that received GAO, the sealant was applied over the dura and around the nerve roots, and it was used to fill the laminectomy cavity before it polymerized. In 36 control animals, the same surgical treatment was performed, but the rats did not receive GAO. During the early postoperative period, a significant decrease in the occurrence of epidural hematoma was found in the GAO-treated rats. In contrast to findings in control rats, a thin white connective tissue layer was found between the dura and surrounding muscles after GAO had degraded and been absorbed. One month posttreatment, no epidural scar adhesion was found between the tissue layer and the dura in the GAO-treated animals. Three months postoperatively, both gross inspection and histological examination further confirmed that formation of epidural adhesions was significantly inhibited in the rats treated with GAO. No special inflammatory reaction was observed, and the healing of skin and muscle lesions was not affected by either treatment. Conclusions. The data obtained in this study suggest that the GAO collagen—based sealant may be an effective biomaterial to prevent epidural adhesions in vivo after laminectomy.

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Contribution of polyamine oxidase to brain injury after trauma

Journal of Neurosurgery ◽

10.3171/jns.1999.90.6.1078 ◽

1999 ◽

Vol 90 (6) ◽

pp. 1078-1082 ◽

Cited By ~ 34

Author(s):

Aclan Doğan ◽

a. Muralikrishna Rao ◽

Muştafa K. Baskaya ◽

James Hatcher ◽

Cuneyt Temiz ◽

...

Keyword(s):

Brain Injury ◽

Traumatic Injury ◽

Polyamine Oxidase ◽

Cresyl Violet ◽

Sprague Dawley ◽

Edema Formation ◽

Content Type ◽

Sprague Dawley Rats ◽

Mdl 72527 ◽

Fine Print

Object. The possible role of the polyamine interconversion pathway on edema formation, traumatic injury volume, and tissue polyamine levels after traumatic brain injury (TBI) was studied using an inhibitor of the interconversion pathway enzyme, polyamine oxidase.Methods. Experimental TBI was induced in Sprague—Dawley rats by using a controlled cortical impact device at a velocity of 3 m/second, resulting in a 2-mm deformation. Immediately after TBI was induced, 100 mg/kg of N1,N4-bis(2,3-butadienyl)-1,4-butanediamine 2HCl (MDL 72527) or saline was injected intraperitoneally. Brain water content and tissue polyamine levels were measured at 24 hours after TBI. Traumatic injury volume was evaluated using 2% cresyl violet solution 7 days after TBI occurred. The MDL 72527 treatment significantly reduced brain edema (80.4 ± 0.8% compared with 81.2 ± 1.2%, p < 0.05) and injury volume (30.1 ± 6.6 mm3 compared with 42.7 ± 13.3 mm3, p < 0.05) compared with the saline treatment. The TBI caused a significant increase in tissue putrescine levels at the traumatized site (65.5 ± 26.5 pmol/g in the cortex and 70.9 ± 22.4 pmol/g in the hippocampus) compared with the nontraumatized site (7 ± 2.4 pmol/g in the cortex and 11.4 ± 6.4 pmol/g in the hippocampus). The increase in putrescine levels in both the traumatized and nontraumatized cortex and hippocampus was reduced by a mean of 60% with MDL 72527 treatment.Conclusions. These results demonstrate, for the first time, that the polyamine interconversion pathway has an important role in the increase of putrescine levels after TBI and that the polyamine oxidase inhibitors, blockers of the interconversion pathway, can be neuroprotective against edema formation and necrotic cavitation after TBI.

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Angiogenic activity of the atherosclerotic carotid artery plaque

Journal of Neurosurgery ◽

10.3171/jns.1989.70.6.0942 ◽

1989 ◽

Vol 70 (6) ◽

pp. 942-945 ◽

Cited By ~ 21

Author(s):

Hanoch Alpern-Elran ◽

Nicholas Morog ◽

Françoise Robert ◽

Gayle Hoover ◽

Norman Kalant ◽

...

Keyword(s):

Carotid Artery ◽

Atherosclerotic Plaque ◽

Cellular Proliferation ◽

Histological Evaluation ◽

Atherosclerotic Plaques ◽

Carotid Artery Plaque ◽

Angiogenic Activity ◽

Content Type ◽

Fine Print

✓ Neovascularization is observed in complicated atherosclerotic plaques associated with cellular proliferation, plaque hemorrhage, and thrombosis. The angiogenic activity of 278 plaque fragments was tested; the fragments were taken from 12 patients with cerebral ischemia who underwent carotid endarterectomy. Angiogenesis, determined by the sustained ingrowth of new vessels in the rabbit cornea, was induced in 125 (45%) of these fragments. By contrast, angiogenesis was found in only two (2.4%) of 80 control tissues (p < 0.001): in none of 22 samples of boiled atherosclerotic plaque; in two of 26 samples of normal rabbit carotid artery; and in none of 32 samples of nonatherosclerotic human uterine artery. Histological evaluation revealed that the cellular zones (composed mainly of smooth-muscle cells) were highly angiogenic, with 97 (76%) of 127 samples showing angiogenesis compared with 23 (17%) of 132 acellular fragments that consisted of amorphic, necrotic, calcific, lipid-laden material (p < 0.001). These results indicate that angiogenesis in vivo is a function of the cellular component of the advanced atherosclerotic plaque, and is not expressed in the normal, stable arterial wall. The fragile new vessels could promote the growth of the plaque or be a source of hemorrhages, microinfarcts, and plaque fissures that convert a stable, silent lesion to an expanding, ulcerated, thrombotic, symptomatic plaque.

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An In Vivo Study in Rat Femurs of Bioactive Silicate Coatings on Titanium Dental Implants

Journal of Clinical Medicine ◽

10.3390/jcm9051290 ◽

2020 ◽

Vol 9 (5) ◽

pp. 1290

Author(s):

Giulia Brunello ◽

Lisa Biasetto ◽

Hamada Elsayed ◽

Elia Sbettega ◽

Chiara Gardin ◽

...

Keyword(s):

Synovial Fluid ◽

Knee Joints ◽

Histological Evaluation ◽

Micro Ct ◽

Sprague Dawley ◽

Micro Computed Tomography ◽

Suitable Material ◽

Sprague Dawley Rats ◽

Ct Data

Silica-based ceramics have been proposed for coating purposes to enhance dental and orthopedic titanium (Ti) implant bioactivity. The aim of this study was to investigate the influence of sphene-based bioceramic (CaO.TiO2.SiO2) coatings on implant osseointegration in vivo. Sphene coatings were obtained from preceramic polymers and nano-sized active precursors and deposited by an automatic airbrush. Twenty customized Ti implants, ten sphene-coated and ten uncoated rough implants were implanted into the proximal femurs of ten Sprague-Dawley rats. Overall, cortical and cancellous bone-to-implant contact (BIC) were determined using micro-computed tomography (micro-CT) at 14 and 28 days. Moreover, peri-implant bone healing was histologically and histomorphometrically evaluated. The white blood cell count in the synovial fluid of the knee joints, if present, was also assessed. No difference in the BIC values was observed between the sphene-coated and uncoated implants, overall and in the two bone compartments (p > 0.05). Delamination of the coating occurred in three cases. Consistently with micro-CT data, the histological evaluation revealed no differences between the two groups. In addition, no synovial fluid could be collected on the test side, thus confirming sphene biocompatibility. In conclusion, sphene coating was found to be a suitable material for biomedical applications. Further studies are needed to improve coating adhesion to the implants.

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Posttraumatic hypothermia in the treatment of axonal damage in an animal model of traumatic axonal injury

Journal of Neurosurgery ◽

10.3171/jns.1998.89.2.0303 ◽

1998 ◽

Vol 89 (2) ◽

pp. 303-309 ◽

Cited By ~ 111

Author(s):

Hiroyasu Koizumi ◽

John T. Povlishock

Keyword(s):

Axonal Injury ◽

Protective Effects ◽

Sprague Dawley ◽

Content Type ◽

Behavioral Abnormalities ◽

Minute Period ◽

Sprague Dawley Rats ◽

Axonal Density ◽

Pontomedullary Junction ◽

Fine Print

Object. Many investigators have demonstrated the protective effects of hypothermia following traumatic brain injury (TBI) in both animals and humans. Typically, this protection has been evaluated in relation to the preservation of neurons and/or the blunting of behavioral abnormalities. However, little consideration has been given to any potential protection afforded in regard to TBI-induced axonal injury, a feature of human TBI. In this study, the authors evaluated the protective effects of hypothermia on axonal injury after TBI in rats. Methods. Male Sprague—Dawley rats weighing 380 to 400 g were subjected to experimental TBI induced by an impact-acceleration device. These rats were subjected to hypothermia either before or after injury, with their temporalis muscle and rectal temperatures maintained at 32°C for 1 hour. After this 1-hour period of hypothermia, rewarming to normothermic levels was accomplished over a 90-minute period. Twenty-four hours later, the animals were killed and semiserial sagittal sections of the brain were reacted for visualization of the amyloid precursor protein (APP), a marker of axonal injury. The density of APP-marked damaged axons within the corticospinal tract at the pontomedullary junction was calculated for each animal. In all hypothermic animals, a significant reduction in APP-marked damaged axonal density was found. In animals treated with preinjury, immediate postinjury, and delayed hypothermia, the density of damaged axons was dramatically reduced in comparison with the untreated controls (p < 0.05). Conclusions. The authors infer from these findings that early as well as delayed posttraumatic hypothermia results in substantial protection in TBI, at least in terms of the injured axons.

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Toxicokinetic and Genotoxicity Study of NNK in Male Sprague-Dawley Rats Following Nose-Only Inhalation Exposure, Intraperitoneal Injection, and Oral Gavage

Toxicological Sciences ◽

10.1093/toxsci/kfab049 ◽

2021 ◽

Author(s):

Shu-Chieh Hu ◽

Matthew S Bryant ◽

Estatira Sepehr ◽

Hyun-Ki Kang ◽

Raul Trbojevich ◽

...

Keyword(s):

Human Lung ◽

Inhalation Exposure ◽

Systemic Exposure ◽

Sprague Dawley ◽

Oral Gavage ◽

Sd Rats ◽

New Information ◽

Sprague Dawley Rats ◽

Tissue Specimens

Abstract The tobacco-specific nitrosamine NNK [4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone] is found in tobacco products and tobacco smoke. NNK is a potent genotoxin and human lung carcinogen; however, there are limited inhalation data for the toxicokinetics (TK) and genotoxicity of NNK in vivo. In the present study, a single dose of 5x10−5, 5x10−3, 0.1, or 50 mg/kg body weight (BW) of NNK, 75% propylene glycol (vehicle control), or air (sham control) was administered to male Sprague-Dawley (SD) rats (9-10 weeks age) via nose-only inhalation (INH) exposure for 1 hour. For comparison, the same doses of NNK were administered to male SD rats via intraperitoneal (IP) injection and oral gavage (PO). Plasma, urine, and tissue specimens were collected at designated timepoints and analyzed for levels of NNK and its major metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) and tissue levels of DNA adduct O6-methylguanine by LC/MS/MS. TK data analysis was performed using a non-linear regression program. For the genotoxicity subgroup, tissues were collected at 3 hours post-dosing for comet assay analysis. Overall, the TK data indicated that NNK was rapidly absorbed and metabolized extensively to NNAL after NNK administration via the three routes. The IP route had the greatest systemic exposure to NNK. NNK metabolism to NNAL appeared to be more efficient via INH than IP or PO. NNK induced significant increases in DNA damage in multiple tissues via the three routes. The results of this study provide new information and understanding of the toxicokinetics and genotoxicity of NNK.

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Pharmacological comparison of four biopolymeric natural gums as hemostatic agents for management of bleeding wounds: preliminary in vitro and in vivo results

Future Journal of Pharmaceutical Sciences ◽

10.1186/s43094-021-00237-z ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Himanshu Kushwah ◽

Nidhi Sandal ◽

Meenakshi Chauhan ◽

Gaurav Mittal

Keyword(s):

Xanthan Gum ◽

Guar Gum ◽

Human Lymphocytes ◽

Sprague Dawley ◽

Gum Tragacanth ◽

Civilian Trauma ◽

Sprague Dawley Rats ◽

Cytotoxicity Studies

Abstract Background Uncontrolled bleeding is one of the primary reasons for preventable death in both civilian trauma and military battle field. This study evaluates in vitro and in vivo hemostatic potential of four biopolymeric natural gums, namely, gum tragacanth, guar gum, xanthan gum, and gum acacia. In vitro evaluation of whole blood clotting time and erythrocyte agglutination assay were carried out. In vitro cytotoxicity studies with respect to each gum were done in human lymphocytes to ascertain percent cell viability. In vivo hemostatic potential of each gum (as sponge dressing and powder form) was evaluated in Sprague Dawley rats using tail bleeding assay and compared with commercially available hemostatic sponge. Other important parameters like (a) time taken for complete hemostasis, (b) amount of blood absorbed, (c) adherence strength of developed hemostatic dressing(s), (d) incidence of re-bleeding, and (e) survival of animals were also studied. Results Of the four test gums studied, xanthan gum (@3mg/ml of blood) and gum tragacanth (@35mg/ml of blood) were able to clot blood in least time (58.75±6.408 s and 59.00±2.082 s, respectively) and exhibited very good hemostatic potential in vitro. Except for xanthan gum, all other test gums did not exhibit any significant cytotoxicity at different time points till 24 h. In rat tail bleeding experiments, gum tragacanth sponge dressing and powder achieved hemostasis in least time (156.2±12.86 s and 76±12.55 s, respectively) and much earlier than commercially available product (333.3±38.84 s; p˂0.01). Conclusion Results indicate potential of gum tragacanth to be developed into a suitable hemostatic product.

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Bioavailability in Vivo of Benzo[a]Pyrene Adsorbed to Diesel Particulate

Toxicology and Industrial Health ◽

10.1177/074823379100700302 ◽

1991 ◽

Vol 7 (3) ◽

pp. 125-139 ◽

Cited By ~ 6

Author(s):

David R. Bevan ◽

David M. Ruggio

Keyword(s):

Health Risks ◽

Quantitative Description ◽

Intratracheal Instillation ◽

Direct Analysis ◽

Sprague Dawley ◽

Reasonable Estimate ◽

Diesel Particulate ◽

Sprague Dawley Rats

To evaluate health risks associated with exposure to particulates in the environment, it is necessary to quantify the bioavailability of carcinogens associated with the particulates. Direct analysis of bioavailability in vivo is most readily accomplished by adsorbing a radiolabeled form of the carcinogen to the particulate. A sam ple of native diesel particulate collected from an Oldsmobile die sel engine that contained 1.03 μ g benzo[ a] pyrene ( BaP)/ g particulate was supplemented with exogenous [ 3 H]- BaP to pro duce a particulate containing 2.62 μ g BaP/g. To insure that elu tion of BaP from native and [3 H] -BaP-supplemented particulate was similar, in vitro analyses were performed. When using phos pholipid vesicles composed of dimyristoylphosphatidylcholine (DMPC), 1.52% of total BaP was eluted from native particulate into the vesicles in 18 hrs; from [ 3 H] -BaP supplemented particu late, 1.68% was eluted. Using toluene as eluent, 2.55% was eluted from native particulate, and 8.25% from supplemented particulate, in 6 hrs. Supplemented particulate was then instilled intratracheally into male Sprague-Dawley rats and distribution of radioactivity was analyzed at selected times over 3 days. About 50% of radioactivity remained in lungs at 3 days following instil lation, with 30% being excreted into feces and the remainder dis tributed throughout the organs of the rats. To estimate the amount of radioactivity that entered feces through swallowing of a portion of the instilled dose, [3 H] -BaP-supplemented particu late was instilled intratracheally into rats that had a cannula sur gically implanted in the bile duct. Rate of elimination of radio activity into bile was monitored; 10.6% of radioactivity was re covered in 6 hr, an amount slightly lower than the 12.8% ex creted in 6 hrs into feces of animals with intact bile ducts. Our studies provide a quantitative description of the distribution of BaP and its metabolites following intratracheal instillation of diesel particulate. Because rates of elution of BaP in vitro are similar for native diesel particulate and particulate with supple mental [ 3H] -BaP, our results provide a reasonable estimate of the bioavailability in vivo of BaP associated with diesel particu late.

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Invasion of human glioma biopsy specimens in cultures of rodent brain slices: a quantitative analysis

Journal of Neurosurgery ◽

10.3171/jns.2002.97.1.0169 ◽

2002 ◽

Vol 97 (1) ◽

pp. 169-176 ◽

Cited By ~ 34

Author(s):

Sophie de Boüard ◽

Christo Christov ◽

Jean-Sébastien Guillamo ◽

Lina Kassar-Duchossoy ◽

Stéphane Palfi ◽

...

Keyword(s):

Cell Lines ◽

Brain Slices ◽

Lower Grade ◽

Human Glioma ◽

Newborn Mice ◽

Content Type ◽

Biopsy Specimens ◽

Rodent Brain ◽

Fine Print

Object. The reliable assessment of the invasiveness of gliomas in vitro has proved elusive, because most invasion assays inadequately model in vivo invasion in its complexity. Recently, organotypical brain cultures were successfully used in short-term invasion studies on glioma cell lines. In this paper the authors report that the invasiveness of human glioma biopsy specimens directly implanted into rodent brain slices by using the intraslice implantation system (ISIS) can be quantified with precision. The model was first validated by the demonstration that, in long-term studies, established glioma cells survive in the ISIS and follow pathways of invasion similar to those in vivo. Methods. Brain slices (400 µm thick) from newborn mice were maintained on millicell membranes for 15 days. Cells from two human and one rodent glioblastoma multiforme (GBM) cell lines injected into the ISIS were detected by immunohistochemistry or after transfection with green fluorescent protein—containing vectors. Preferential migration along blood vessels was identified using confocal and fluorescent microscopy. Freshly isolated (≤ 24 hours after removal) 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate—prelabeled human glioma biopsy specimens were successfully implanted in 19 (83%) of 23 cases, including 12 GBMs and seven lower grade gliomas (LGGs). Morphometric quantification of distance and density of tumor cell invasion showed that the GBMs were two to four times more invasive than the LGGs. Heterogeneity of invasion was also observed among GBMs and LGGs. Directly implanted glioma fragments were more invasive than spheroids derived from the same biopsy specimen. Conclusions. The ISIS combines a high success rate, technical simplicity, and detailed quantitative measurements and may, therefore, be used to study the invasiveness of biopsy specimens of gliomas of different grades.

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