In vitro and in vivo inhibition of acetylcholinesterase and carboxylesterase by metals in zebrafish (Danio rerio)

Metals are natural components in ecosystems; however, if these elements are in excess, they can have adverse effects on living organisms. This study analyzes the interference of copper, lead, iron and cadmium in acetylcholinesterase (AChE) and carboxylesterase (CbE) activities in zebrafish. AChE was significantly inhibited in vitro by copper, iron, lead and cadmium at higher concentrations (10 and 20 mmol/L), whereas CbE was inhibited only at a concentration of 20 mmol/L. In vivo, only lead and cadmium were able to cause AChE inhibition at higher concentrations, while iron didn't cause any changes, and copper promoted an increase in AChE activity at a concentration of 0.06 mg/L. CbE activity did not change at any of the times (two and seven days) and concentrations tested, except in the case of copper exposure, which resulted in a decrease in CbE activity. Indeed, iodoacetamide treatment didn't changed AChE neither CbE activities, results which indicate that the metal inhibiting effect is probably not due to its biding to thiol groups close the active site of the enzyme. This outcome reveals that metals are important esterase inhibitors in zebrafish, and should be considered in environmental monitoring studies that use esterase inhibition as exposure biomarkers of organophosphate and carbamate pesticides. © 2012 Elsevier Ltd. All rights reserved.

The role of B-mode ultrasonography in the musculoskeletal anatomical evaluation of the cervical region of the dog spine

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Clinical manifestations and experimental studies on the spine extract of the toadfish Porichthys porosissimus

Toadfish are fish from the family Batrachoididae that are found in marine and brackish environment around the world. Among the toadfish, Porichthys genus is very common, where Porichthys porosissimus, also called Atlantic Midshipman is found in Southwest Atlantic, from Rio de Janeiro, Brazil to eastern Argentina. There was no consensus about the classification of the genus Porichthys as venomous fish because so far there are no published Studies regarding human envenomations and/or toxic activities induced in animal models. Herein, we report two conclusive envenoming in human beings caused by P porosissimus spines, with clear signs and symptoms that were very important for the development of our experimental studies. We demonstrated that the P. porosissimus spine extract, now venom, can induce nociceptive and edematogenic responses in mice as well an induction of an inflammatory response elicited by intravital microscopy and leukocyte migration. Finally, we identified in the P. porosissimus spine extract, through analysis by mass spectrometry, the presence of proteins previously detected in the venoms of other fish species and other venomous animals. We believe that based on our studies we will dismiss the non-venomous nature of this fish and clarify this issue. (C) 2014 Elsevier Ltd. All rights reserved.

conventional radiography and computed tomography to cervical spine study of adult horses - review

The imaging is essential to aid the diagnosis of horses that have performance decrease associated with any pain or clinical signs related to the vertebral column. Radiography is the first imaging examination performed in these cases, particularly for disorders affecting the cervical region. However, this technique has limitations when the study of subtle changes due to the overlapping of adjacent structures. Computed tomography is a new diagnostic method in Brazil for the study of bone disorders in horses, but it is of great diagnostic value associate with the radiographic examination in order to provide an accurate assessment of the study area, owing to superiority in image quality when compared to conventional radiography. The aim of this study is increase and update knowledge of diagnostic imaging available to investigate cervical disorders in horses.

Vertebral spine of Tamandu-mirim Tamandua tetradactyla

Anatomical studies of the anteater (Tamandua tetradactyla) are scarce and the articles that describe the vertebral column of this species have variations in the number of thoracic and lumbar vertebrae. This study had the objective of adding data to the existing literature about the anatomical composition of an anteater's vertebral column using radiographic and tomographic exams. Based on the cadaver of a young female anteater, we observed a total of 7 cervical, 16 thoracic, 3 lumbar and 5 sacral vertebrae, which differed from the cited literature, especially with respect to the thoracic vertebrae. This demonstrates the need for studies with a larger number of individuals in order to standardize possible anatomic variations for the species.

Validation of cone-beam computed tomography and magnetic resonance imaging of the porcine spine: a comparative study with multidetector computed tomography and anatomical specimens

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Image-Guided Cryoablation of the Spine in a Swine Model: Clinical, Radiological, and Pathological Findings with Light and Electron Microscopy

This study was designed to present the feasibility of an in vivo image-guided percutaneous cryoablation of the porcine vertebral body. Methods The institutional animal care committee approved this study. Cone-beam computed tomography (CBCT)-guided vertebral cryoablations (n = 22) were performed in eight pigs with short, 2-min, single or double-freezing protocols. Protective measures to nerves included dioxide carbon (CO2) epidural injections and spinal canal temperature monitoring. Clinical, radiological, and pathological data with light (n = 20) or transmission electron (n = 2) microscopic analyses were evaluated after 6 days of clinical follow-up and euthanasia. Results CBCT/fluoroscopic-guided transpedicular vertebral body cryoprobe positioning and CO2 epidural injection were successful in all procedures. No major complications were observed in seven animals (87.5 %, n = 8). A minor complication was observed in one pig (12.5 %, n = 1). Logistic regression model analysis showed the cryoprobe-spinal canal (Cp-Sc) distance as the most efficient parameter to categorize spinal canal temperatures lower than 19 °C (p<0.004), with a significant Pearson’s correlation test (p < 0.041) between the Cp-Sc distance and the lowest spinal canal temperatures. Ablation zones encompassed pedicles and the posterior wall of the vertebral bodies with an inflammatory rim, although no inflammatory infiltrate was depicted in the surrounding neural structures at light microscopy. Ultrastructural analyses evidenced myelin sheath disruption in some large nerve fibers, although neurological deficits were not observed. Conclusions CBCT-guided vertebral cryoablation of the porcine spine is feasible under a combination of a short freezing protocol and protective measures to the surrounding nerves. Ultrastructural analyses may be helpful assess the early modifications of the nerve fibers.

Whole-body computerized tomography and concomitant spine and head injuries A study of 355 cases

The authors present a prospective study on the coexistence of spinal injury (SI) and severe traumatic brain injury (TBI) in patients who were involved in traffic accidents and arrived at the Emergency Department of Hospital das Clinicas of the University of Sao Paulo between September 1, 2003 and December 31, 2009. A whole-body computed tomography was the diagnostic method employed in all cases. Both lesions were observed simultaneously in 69 cases (19.4%), predominantly in males (57 individuals, 82.6%). Cranial injuries included epidural hematoma, acute subdural hematoma, brain contusion, ventricular hemorrhage and traumatic subarachnoid hemorrhage. The transverse processes were the most fragile portion of the vertebrae and were more susceptible to fractures. The seventh cervical vertebra was the most commonly affected segment, with 24 cases (34.78%). The distribution of fractures was similar among the other cervical vertebrae, the first four thoracic vertebrae and the lumbar spine. Neurological deficit secondary to SI was detected in eight individuals (11.59%) and two individuals (2.89%) died. Traumatic subarachnoid hemorrhage was the most common intracranial finding (82.6%). Spinal surgery was necessary in 24 patients (34.78%) and brain surgery in 18 (26%). Four patients (5.79%) underwent cranial and spinal surgeries. The authors conclude that it is necessary a judicious assessment of the entire spine of individuals who presented in coma after suffering a brain injury associated to multisystemic trauma and whole-body CT scan may play a major role in this scenario.

The ischial spine sign: does pelvic tilt and rotation matter?

Although the ischial spine sign (ISS) has been advocated to detect acetabular retroversion, it is unknown whether the sign is valid on anteroposterior (AP) pelvic radiographs with tilted or rotated pelves. We therefore evaluated reliability of the ISS as a tool for diagnosing acetabular retroversion in the presence of considerable pelvic tilt and/or malrotation. We obtained radiographs of 20 cadaver pelves in 19 different malorientations resulting in 380 pelvis images (760 hips) for evaluation. In addition, 129 clinical radiographs of patients' hips that had varying pelvis orientations were reviewed. We found an overall sensitivity of 81% (90%), specificity of 70% (71%), positive predictive value of 77% (80.7%), and negative predictive value of 75% (85%) in the cadaver (patient) hips. Our data suggest the ISS is a valid tool for diagnosing acetabular retroversion on plain radiographs taken using a standardized technique regardless of the degree of pelvic tilt and rotation.

DensiProbe Spine: a novel instrument for intraoperative measurement of bone density in transpedicular screw fixation

STUDY DESIGN.: Cadaver study. OBJECTIVE.: To determine bone strength in vertebrae by measuring peak breakaway torque or indentation force using custom-made pedicle probes. SUMMARY OF BACKGROUND DATA.: Screw performance in dorsal spinal instrumentation is dependent on bone quality of the vertebral body. To date no intraoperative measuring device to validate bone strength is available. Destructive testing may predict bone strength in transpedicular instrumentations in osteoporotic vertebrae. Insertional torque measurements showed varying results. METHODS.: Ten human cadaveric vertebrae were evaluated for bone mineral density (BMD) measurements by quantitative computed tomography. Peak torque and indentation force of custom-made probes as a measure for mechanical bone strength were assessed via a transpedicular approach. The results were correlated to regional BMD and to biomechanical load testing after pedicle screw implementation. RESULTS.: Both methods generated a positive correlation to failure load of the respective vertebrae. The correlation of peak breakaway torque to failure load was r = 0.959 (P = 0.003), therewith distinctly higher than the correlation of indentation force to failure load, which was r = 0.690 (P = 0.040). In predicting regional BMD, measurement of peak torque also performed better than that of indentation force (r = 0.897 [P = 0.002] vs. r = 0.777 [P = 0.017]). CONCLUSION.: Transpedicular measurement of peak breakaway torque is technically feasible and predicts reliable local bone strength and implant failure for dorsal spinal instrumentations in this experimental setting.