Search

Airway complications after anterior cervical surgery are rare but potentially lethal. The purpose of this study was to identify the natural course of prevertebral soft tissue swelling after one- or two-level anterior cervical discectomy and fusion (ACDF) in order to prevent lethal airway obstruction after ACDF. Eighty-seven patients scheduled for one- or two-level ACDF were studied prospectively. Lateral radiographs of the cervical spine were taken preoperatively, postoperatively on the day of surgery and on the first, second, third, fourth, and fifth days after operation. Prevertebral soft tissue was measured from C2 to C6 on cervical spine lateral radiographs. The anteroposterior (AP) thickness of the prevertebral soft tissue was measured at each cervical level from C2 to C6. Prevertebral soft tissue swelling occurred postoperatively and increased markedly on the second day after operation. The maximum swelling was found on the second and third days. In fusions above C5 swelling was most prominent at C2, 3. Gradual decrease in swelling was observed after the fourth postoperative day. Prominent swelling was noted at the second, third, and fourth cervical levels. There was no significant difference in swelling when comparing one-level and two-level ACDF. Only one patient required reintubation (1.1%). In conclusion, in this prospective study of 87 patients fused at one or two levels in the cervical spine peak prevertebral soft tissue swelling was observed on the second and third days after the surgery. [ABSTRACT FROM AUTHOR]

Abstract Delayed vertebral collapse after osteoporotic spinal fractures may cause progressive kyphosis, neurological deficits, and chronic back pain. We treated 14 consecutive patients with posterolateral decompression and posterior reconstruction and followed them over a period ranging from 24 to 54 months. The mean age was 67 (range: 62-72) years and the fracture level was T12 and L1. Seven patients were graded as Frankel stage C and seven as stage D. The mean segmental kyphotic angle was 22.6° (7-29°) preoperatively, 4.4° (1-6°) postoperatively, and 6.8° (2-15°) at the final follow-up. The pain score on a visual analogue scale improved from 9.5 preoperatively to 2.7 postoperatively, and the neurological status improved in all patients. Bone fusion was present 9 months after operation. Of four surgical complications, two were dural tears, one a superficial infection, and there was one death due to an acute adrenal insufficiency. Posterolateral decompression with posterior reconstruction is a useful treatment for patients with delayed osteoporotic vertebral collapse. Résumé Le collapsus vertébral secondaire, après une fracture vertébrale ostéoporotique, peut créer une cyphose progressive, un déficit neurologique et des lombalgies chroniques. Nous avons traité 14 malades consécutifs par décompression postérolaterale et reconstruction postérieure et les avons suivis de 24 à 54 mois. L'âge moyen était 67 (62-72) années. Le niveau de la fracture était T12 et L1. Sept malades ont été notés comme Frankel stade C et sept comme stade D. L'angle cyphotique segmentaire moyen était 22.6° (7-29°) avant l'opération, 4.4° (1-6°) postopératoire, et 6.8° (2-15°) au dernier examen. Le score de la douleur sur une échelle analogue visuelle s'est amélioré de 9.5 en préopératoire à 2.7 en postopératoire. Le statut neurologique a été amélioré chez tous les malades. La fusion osseuse était visible 9 mois après la chirurgie. Il y avait quatre complications chirurgicales, deux brèches duremériennes, une infection superficielle et un décés dû à une insuffisance surrénale aiguë. La décompression posterolateral avec reconstruction postérieure est une bonne option de traitement chez les malades avec collapsus vertébral différé. [ABSTRACT FROM AUTHOR]

We present an explicit description of the Wu invariant metric on the non-convex Thullen domains. We show that the Wu invariant Hermitian metric, which in general behaves as nicely as the Kobayashi metric under holomorphic mappings, enjoys better regularity in this case. Furthermore, we show that the holomorphic curvature of the Wu metric is bounded from above everywhere by $-1/2$. This leads the Wu metric to be a natural solution to a conjecture of Kobayashi in the case of non-convex Thullen domains. [ABSTRACT FROM AUTHOR]

A novel temporal contrast filter (TCF)-based method was developed to detect supersonic small infrared targets. The proposed hysteresis threshold-based detection followed by the TCF can enhance the accuracy of the target position, the robustness to background clutter and the velocity range of moving targets compared with the conventional temporal variance filter-based method. [ABSTRACT FROM AUTHOR]

This work is devoted to the investigation of the discharge characteristics of an ac arc plasma torch with a well-type cathode working in air and CO2. The electrical characteristics, plasma jet image and optical emission profile are investigated by varying the discharge power and the gas flow rate. The dynamic behaviour of arc voltage and current is characterized by smooth-shaped waveforms, regularly iterated with a driving frequency. The moving of arc spot positions is inferred from the measured waveforms, and compared with that observed in dc torches. A simple lifetime test is performed to verify the speculation that the arc spots in ac operation move continuously over a wide region with a very high speed. The result shows that the electrode lifetime can be enhanced by combining the vortex motion of arc gas with the ac driving. [ABSTRACT FROM AUTHOR]

Flavonoid has anti-oxidant properties and has been shown to protect cells against oxygen radical damage. This study therefore, evaluated the effect of flavonoid on the in vitrodevelopment ability of porcine embryos produced by parthenogenesis (PA) or somatic cell nuclear transfer (SCNT). Porcine embryos were produced from abattoir-derived prepubertal oocytes either by PA or SCNT of fetal fibroblast into enucleated oocytes essentially as we described earlier (Gupta et al.2008 Mol. Reprod. Dev. 75, 588–597). One-cell embryos were subsequently cultured in NCSU23 + 0.4% polyvinyl alcohol supplemented with or without 10 μmflavanoid for 7 days at 39°C in a humidified atmosphere of 5% CO2in air. Results showed that the presence of flavonoid in the culture medium increased (v. controls) the rate of blastocyst in both PA (31.7 ± 4.0 v. 20.4 ± 2.0%) and SCNT (20.6 ± 2.5 v. 12.2 ± 2.9%) groups, respectively (P< 0.05). These blastocysts also had higher ability to hatch (PA: 53.7 ± 3.6 v. 34.0 ± 2.4%; SCNT: 70.9 ± 2.5 v. 45.7 ± 2.9%) and contained higher cell number (PA: 38.9 ± 2.0 v. 31.3 ± 2.1; SCNT: 37.5 ± 2.0 v. 29.7 ± 2.5) than those of control groups (P< 0.05). Western blot analysis of parthenogenetic blastocysts showed that, flavonoid also reduced the expression of caspase-3 and p38 mitogen-activated protein kinase (MAPK) proteins by 3.1 ± 0.1 and 7.7 ± 0.2 fold, respectively while expression of ERK1/2 protein was increased by 4.7 ± 2.3 fold. The 2′,7′-dichlorofluorescene fluorescence staining of embryos further revealed that the activity of reactive oxygen species (ROS) was significantly reduced in flavonoid treated embryos by 2 fold(P< 0.05). These data therefore, suggest that flavonoid may improve the in vitrodevelopment rate and quality of porcine embryos by reducing ROS activity and change in protein expression. [ABSTRACT FROM AUTHOR]