Contribution of the xenograft bone plate-screw system in lumbar transpedicular stabilization of dogs: an in-vitro study

We performed biomechanical comparison of a xenograft bone plate-screw (XBPS) system for achieving cadaveric lumbar transpedicular stabilization (TS) in dogs. Twenty dogs' cadaveric L2-4 lumbar specimens were harvested and their muscles were removed, but the discs and ligaments were left intact. These specimens were separated to four groups: the L2-4 intact group as control (group I, n = 5), the L3 laminectomy and bilateral facetectomy group (LBF) (group II, n = 5), the LBF plus TS with metal plate-screw group (group III, n = 5) and the LBF plus TS with XBPS group (group IV, n = 5). Five kinds of biomechanical tests were applied to the specimens: flexion, extension, left-right bending and rotation. The averages of the 16 stiffness values were calculated and then these were statistically analyzed. The statistical results show that the XBPS system contributes spinal stability and this system can be a good choice for achieving TS

Comparison of prognostic scores and surgical approaches to treat spinal metastatic tumors: A review of 57 cases

Surgical treatment of metastatic spinal cord compression with or without neural deficit is controversial. Karnofsky and Tokuhashi scores have been proposed for prognosis of spinal metastasis. Here, we conducted a retrospective analysis of Karnofsky and modified Tokuhashi scores in 57 consecutive patients undergoing surgery for secondary spinal metastases to evaluate the value of these scores in aiding decision making for surgery. Comparison of preoperative Karnofsky and modified Tokuhashi scores with the type of the surgical approach for each patient revealed that both scores not only reliably estimate life expectancy, but also objectively improved surgical decisions. When the general status of the patient is poor (i.e., Karnofsky score less than 40% or modified Tokuhashi score of 5 or greater), palliative treatments and radiotherapy, rather than surgery, should be considered

Contribution of Na+, HCO3-/Cl- exchanger activity on recovery from induced-acidosis in oocyte, zygote and embryo of Balb/c strain mouse.

40th Annual Meeting of the Society-for-the-Study-of-Reproduction -- JUL 21-25, 2007 -- San Antonio, TXWOS: 000248002500130…Soc Study Repro

Late Quaternary climate and sea-level changes recorded in sediment composition off the Buyuk Menderes River delta (eastern Aegean Sea, Turkey)

WOS: 000248142700015Influences of Holocene climatic and sea level changes on sedimentation on the continental shelf off the Buyuk Menderes River delta, SW Turkey were investigated using grain size and X-ray clay mineralogical data on surficial and 14C-dated core sediments collected at 19-81 m water depths. Modern, fine-grained, siliciclastic sediments cover most of the seafloor of inner to mid-shelf areas. A narrow, relict belt extends from northwest to south (at 66-81 m water depths), where sediments are characterized by abundant sand and gravel (27-52%) and biogenic carbonate (16-44%) contents, and microscopic examination suggests an older origin. The radiocarbon ages of mid and lower sections in cores (3670-10,380 yr BP) reflect sedimentation under depositional conditions from early to late Holocene in the study area. Additionally, downcore changes of grain size toward coarser-grained sediments most probably record global climatic effects with sea level changes, specifically the transition from lowstand in early Holocene to highstand at mid-late Holocene. The presence of this relict belt in offshore waters can be attributed largely to active uplift tectonics. The coarser-grained relict belt, compared with available seismic profiles, corresponds to an lowstand unconformity of bottomset beds of the prograding Buyuk Menderes Delta. Reconstruction from nautical charts clearly showed the presence of an E-W-trending submarine canyon ("Paleo-Buyuk Menderes River valley") in the course of Buyuk Menderes Graben. This is interpreted as product of combination of sea-level lowstands and subsidence tectonics throughout the late Quaternary. Smectite (35-62 %), illite (28-51 %) and kaolinite (12-19 %) constitute the dominant clay minerals in the < 2 mu m fraction of the surface sediments. The patterns of clay mineral distribution suggest sediment transport from the Buyuk Menderes River and dispersal from the river to the outer continental shelf by the prevailing current regime. Downcore changes in the clay mineral assemblages (downward-decreasing smectite/iilite ratios) reflect changes in weathering conditions of the terrigenous source, from a colder climate during early Holocene to relatively warmer periods toward the present. Widely occurring partly metamorphosed volcanic rocks characterize the major geological sources of clay minerals on the adjacent hinterland. (c) 2007 Elsevier Ltd and INQUA. All rights reserved

Grain size and heavy mineral distribution as related to hinterland and environmental conditions for modern beach sediments from the Gulfs of Antalya and Finike, eastern Mediterranean

WOS: 000247233200013Backshore sediment samples from 22 beaches along the Antalya and Finike Gulfs have been studied for their grain size, chemical and heavy mineral composition. Data presented here suggest that well- to moderately-sorted (0.41 Phi-0.92 Phi) medium sand (1 Phi-2 Phi) represents dominant mean grain size in most beaches. In contrast, some beaches from the western part of the Gulf of Antalya (Goynuk, Kemer-Kiris and Beldibi) are composed of pebble- to boulder-size grained beaches which are located close to mouths of short and steep-gradient ephemeral rivers entering the sea from the Western Taurus Mountains. The heavy mineral assemblages are dominated by detrital opaque minerals (14-58% magnetite, chromite, and hematite), pyroxene (8-65% augite), amphibole (3-15% tremolite and actinolite), epidote (3-25%), garnet (2-9% pyrope and almandine) and micas (3-20 biotite, muscovite and chlorite). The very high concentrations of heavy minerals (up to 86% of bulk sediment) together with the significant concentrations of some elements found in beach sediments from the Gulf of Finike and western Gulf of Antalya (Fe: 18.40%; Cr: 10.00%; and Ti: 1.32%) are indicative of ultramafic origin, mainly derived from the ophiolitic rocks of the Antalya-Tekirova nappe on coastal hinterland. (c) 2007 Elsevier B.V. All rights reserved

Hemorrhage of Cavernous Malformations During Pregnancy and in the Peripartum Period: Causal or Coincidence? Case Report and Review of the Literature

There is growing evidence to suggest that pregnancy may increase the risk of hemorrhage from cavernous malformations (CMs). In the present case, a 21-year-old primigravida was admitted to the authors\u27 neurosurgical service after a cesarean section. Three weeks before admission she had experienced rapidly progressive bilateral lower-extremity paresthesias. Spinal magnetic resonance (MR) imaging revealed the presence of an intramedullary thoracic lesion. On T2-weighted MR images, heterogeneous signal intensity with a rim of decreased intensity was demonstrated in the spine. The mass was successfully resected, and 1 year later the patient\u27s symptoms had resolved completely. This is the fourth reported case of a spinal intramedullary CM that became symptomatic during pregnancy. The pathogenesis and management of this entity are reviewed

Assessment of right ventricular geometry and mechanics in chronic obstructive pulmonary disease patients living at high altitude

Degree of increase in pulmonary artery pressure (PAP) and adaptive responses in right ventricular morphology and mechanics play an important role in the prognosis of chronic obstructive pulmonary disease (COPD) patients. Three dimensional echocardiography and deformation imaging are recent advancements in echocardiography that allow more through assessment of right ventricle. We aimed to investigate right ventricular geometry and mechanics in a stable COPD population living at moderately high altitude. A total of 26 stable COPD patients with variable disease severity were included to this study. Pulmonary function tests, six minutes walking test (6MWT) and two- and three-dimensional echocardiography were performed for evaluation and data collection. Both systolic (43.06 +/- A 11.79 mmHg) and mean (33.38 +/- A 9.75 mmHg) PAPs were significantly higher in COPD patients compared to controls (p < 0.05, p < 0.001; respectively). Right ventricular volumes were similar between groups, although right ventricular free wall thickness was significantly increased in COPD group. The number of subjects with a sub-normal (< 40 %) right ventricular ejection fraction was significantly higher in COPD group (45.8 vs. 17.4 %, p < 0.05), and the mean right ventricular strain was significantly lower (-21.05 +/- A 3.80 vs. -24.14 +/- A 5.37; p < 0.05). Only mean PAP and body surface area were found as independent predictors for 6MWT distance. Increased PAP and reduced right ventricular contractility were found in COPD patients living at moderately high altitude, although right ventricular volumes were normal. Similar findings can be expected in other COPD patients with high PAP, since these findings probably represents the effect of increased PAP on right ventricular mechanics