Attenuating heatstroke-induced acute lung inflammation, edema, and injury in rats by exercise preconditioning.

BACKGROUND: This study aimed to ascertain whether heat-induced acute lung edema, inflammation, and ischemic damage can be affected by heat shock protein 70 (HSP-70)-mediated exercise preconditioning (EP) in rats. METHODS: Wistar rats were assigned to one of the following four groups: the non-EP + nonheated group, the non-EP + heated group, the EP + heated group, and the EP + HSP-70 antibodies + heated group. EP groups of animals were subjected to a protocol of running on a treadmill for 30 minutes at 20 m/min, 30 minutes at 30 m/min, and 60 minutes at 30 m/min after 1, 2, and 3 weeks of training, respectively. Heated group of animals, under general anesthesia, were put in a folded heating pad of 43°C for 68 minutes. Then, the heated animals were allowed to recover at room temperature. HSP-70 antibodies were injected intravenously 24 hours before heat exposure. RESULTS: As compared with the non heated + non-EP rats, the heated + non-EP rats had significantly higher scores of alveolar edema, neutrophil infiltration, and hemorrhage, acute pleurisy, and increased bronchoalveolar fluid levels of proinflammatory cytokines and ischemic and oxidative damage markers. EP, in addition to inducing overexpression of HSP-70 in lung tissues, significantly attenuated heat-induced acute pulmonary edema, inflammation, and ischemic and oxidative damage in the lungs. HSP-70 antibodies, in addition to reducing HSP-70 expression in the lungs, significantly attenuated the beneficial effects of EP in reducing acute lung inflammation and injury. CONCLUSION: EP may attenuate the occurrence of pulmonary edema, inflammation, as well as ischemic and oxidative damage caused by heatstroke by up-regulating HSP-70 in the lungs.

Beneficial effect of agmatine on brain apoptosis, astrogliosis, and edema after rat transient cerebral ischemia.

BACKGROUND: Although agmatine therapy in a mouse model of transient focal cerebral ischemia is highly protective against neurological injury, the mechanisms underlying the protective effects of agmatine are not fully elucidated. This study aimed to investigate the effects of agmatine on brain apoptosis, astrogliosis and edema in the rats with transient cerebral ischemia. METHODS: Following surgical induction of middle cerebral artery occlusion (MCAO) for 90 min, agmatine (100 mg/kg, i.p.) was injected 5 min after beginning of reperfusion and again once daily for the next 3 post-operative days. Four days after reperfusion, both motor and proprioception functions were assessed and then all rats were sacrificed for determination of brain infarct volume (2, 3, 5-triphenyltetrazolium chloride staining), apoptosis (TUNEL staining), edema (both cerebral water content and amounts of aquaporin-4 positive cells), gliosis (glial fibrillary acidic protein [GFAP]-positive cells), and neurotoxicity (inducible nitric oxide synthase [iNOS] expression). RESULTS: The results showed that agmatine treatment was found to accelerate recovery of motor (from 55 degrees to 62 degrees) and proprioception (from 54% maximal possible effect to 10% maximal possible effect) deficits and to prevent brain infarction (from 370 mm3 to 50 mm3), gliosis (from 80 GFAP-positive cells to 30 GFAP-positive cells), edema (cerebral water contents decreased from 82.5% to 79.4%; AQP4 positive cells decreased from 140 to 84 per section), apoptosis (neuronal apoptotic cells decreased from 100 to 20 per section), and neurotoxicity (iNOS expression cells decreased from 64 to 7 per section) during MCAO ischemic injury in rats. CONCLUSIONS: The data suggest that agmatine may improve outcomes of transient cerebral ischemia in rats by reducing brain apoptosis, astrogliosis and edema.

Biomechanical evaluation of cervical spine fixation after healing in a destabilized cervical spine model in sheep: a comparison of the anterior plating and posterior wiring techniques.

BACKGROUND: We conducted biomechanical evaluation of the anterior plating and posterior wiring techniques for cervical spine stabilization after a course of healing in sheep. METHODS: Seventeen sheep were included, and six of which underwent sham operations (group A, n=6). The other eleven received complete C2-C3 destabilization, followed by intervertebral bone grafting and cervical stabilization either with anterior plating (group B, n=5) or posterior wiring (group C, n=6) techniques. These animals were killed 6 months later. Ligamentous spines (C1-C5) were subjected to the relevantly applied loads. The load-deformation data of the C2-C3 and C3-C4 functional units were recorded and analyzed. RESULTS: At the C2-C3 functional unit, group B had the least motion ranges in flexion, lateral bending, and rotation loads than did the other two groups. Significantly smaller motion ranges of lateral bending and rotation loads were found in group B than in group C (p<0.05). Compared with group A, group C had a decreased motion range in flexion load but showed increased motion range in rotation load. Consequently, group B had superior intervertebral fusion and less osteophyte than did group C. At the C3-C4 functional unit, group B showed significantly decreased motion ranges in extension and lateral bending loads (p<0.05), while group C did not. CONCLUSION: The results indicated that the anterior plate-stabilized spines were more stable over time than did the posterior-wired spines. This biomechanical advantage eventually resulted in superior intervertebral fusion masses in the former, although it also induced a slightly decreased motion range at the contiguous functional unit. In exclusively posterior wired-spines, the weakness for opposing rotation loads might contribute to the formation of osteophytes at the fusion functional unit. These data point out that the mode and stability of implant fixation systems greatly influence the biomechanical redistribution and bone-adaptive remodeling process during healing, which are closely related to the bone graft maturation and osteophytic formations at the fusion level and the occurrence of stiffening problems at the contiguous levels.

Two primary brain tumors, meningioma and glioblastoma multiforme, in opposite hemispheres of the same patient.

We report a case with double primary intracranial tumors of different cell types without phacomatosis. The patient was hospitalized due to progressive memory impairment, headaches, dysarthria and right hemiparesis. Initial computed tomographic (CT) examinations revealed a large hyperdense tumor over the right frontal lobe, suggestive of an extra-axial meningioma. Additionally, there was unusual brain edema in the contralateral hemisphere that subsequently proved to originate from an intrinsic tumor. Staged craniotomies were used to treat the patient. Pathological examinations confirmed the two tumors to be a meningioma and a glioblastoma multiforme, respectively. The patient made an uneventful recovery after treatment. Although meningioma and glioma represent two common primary intracranial tumors, the simultaneous development of the two tumors is rare. A randomly occurring event most likely accounted for this linkage in the patient. We suggest that extraordinary brain edema far remote from the primary brain lesion warrants special attention for identifying other potentially undetected lesions.