Correlation of locations of sacral insufficiency fractures is made to regions of stress depicted by finite element analysis derived from biomechanical models of patient activities.
Sacral ...insufficiency fractures occur at consistent locations. It was postulated that sacral anatomy and sites of stress within the sacrum with routine activities in the setting of osteoporosis are foundations for determining patterns for the majority of sacral insufficiency fractures.
The predominant vertical components of sacral insufficiency fractures most frequently occur bilaterally through the alar regions of the sacrum, which are the thickest and most robust appearing portions of the sacrum instead of subjacent to the central sacrum, which bears the downward force of the spine.
First, the exact locations of 108 cases of sacral insufficiency fractures were catalogued and compared to sacral anatomy. Second, different routine activities were simulated by pelvic models from CT scans of the pelvis and finite element analysis. Analyses were done to correlate sites of stress with activities within the sacrum and pelvis compared to patterns of sacral insufficiency fractures from 108 cases.
The sites of stress depicted by the finite element analysis walking model strongly correlated with identical locations for most sacral and pelvic insufficiency fractures. Consistent patterns of sacral insufficiency fractures emerged from the 108 cases and a biomechanical classification system is introduced. Additionally, alteration of walking mechanics and asymmetric sacral stress may alter the pattern of sacral insufficiency fractures noted with hip pathology (P = 0.002).
Locations of sacral insufficiency fractures are nearly congruous with stress depicted by walking biomechanical models. Knowledge of stress locations with activities, cortical bone transmission of stress, usual fracture patterns, intensity of sacral stress with different activities, and modifiers of walking mechanics may aid medical management, interventional, or surgical efforts.
Genetic resistance is a cornerstone for managing clubroot (
). However, when used repeatedly, a clubroot resistance (CR) gene can be broken rapidly. In this study, canola inbred/hybrid lines carrying ...one or two CR genes (
and
) were assessed against
pathotype X by repeated exposure to the same inoculum source under a controlled environment. Lines carrying two CR genes, either
+
or
+
, showed partial resistance. Selected lines were inoculated with a field pathotype X population (L-G3) at 5 × 10
resting spores/g soil, and all clubs were returned to the soil they came from six weeks after inoculation. The planting was repeated for five cycles, with diseased roots being returned to the soil after each cycle. The soil inoculum was quantified using qPCR before each planting cycle. All lines with a single CR gene were consistently susceptible, maintaining high soil inoculum levels over time. The lines carrying two CR genes showed much lower clubroot severity, resulting in a 10-fold decline in soil inoculum. These results showed that the CR-gene stacking provided moderate resistance against
.
pathotype X, which may also help reduce the pathogen inoculum buildup in soil.
We chose to evaluate the safety and efficacy of combined intrathrombus rtPA and intravenous heparin in cerebral venous thrombosis (CVT).
We treated 12 patients with symptoms of 1 to 40 days' duration ...(eg, headache, somnolence, focal deficits, seizures, and nausea and vomiting). Pretreatment MRI disclosed subtle hemorrhagic venous infarction in 4 patients, obvious hemorrhagic infarction in 2, small parenchymal hemorrhage from recent pallidotomy in 1, and no focal lesion in 5. Magnetic resonance venography and contrast venography identified thrombi in the superior sagittal sinus (SSS) in 3 patients; transverse/sigmoid sinus (TS/SS) in 2; SSS and both TS/SS in 1; SSS and 1 TS/SS in 5; and SSS, 1 TS/SS, and straight sinus in 1 patient. A loading dose of rtPA was instilled throughout the clot at 1 mg/cm, followed by continuous intrathrombus infusion at 1 to 2 mg/h. Intravenous heparin was infused concomitantly.
Flow was restored completely in 6 patients and partially in 3, with a mean rtPA dose of 46 mg (range, 23 to 128 mg) at a mean time of 29 hours (range, 13 to 77 hours). Symptoms improved in these 9 patients concomitantly with flow restoration. Flow could not be restored in 3 patients. In 1 of them, treatment was stopped when little progress had been made, and fibrinogen level dropped to 118 mg/dL. In the other 2 patients, hemorrhagic worsening occurred, and treatment was abbreviated after initial rtPA dosing. In 1 of these, the hematoma was evacuated.
Our experience with intrathrombus rtPA in conjunction with intravenous heparin in patients with CVT is encouraging. This therapy should probably be regarded as unsafe in patients with obvious hemorrhage. Time to restore flow may be faster than with urokinase (an average of 71 hours has been reported for 29 documented patients). Further evaluation of rtPA with heparin in CVT is warranted.
The James Webb Space Telescope Mission Acton, Scott; Adams, Cynthia K.; Aguilar, Jonathan Albert ...
Publications of the Astronomical Society of the Pacific,
06/2023, Letnik:
135, Številka:
1048
Journal Article
Dissection and retraction of the sylvian fissure can cause venous insufficiency and may be an important contributor to postoperative edema or hemorrhage after clipping of a middle cerebral artery ...(MCA) aneurysm. The incidence of changes in the superficial middle cerebral vein (SMCV) and adjacent veins and whether such changes increase the amount of edema or hemorrhage on postoperative CT is the focus of this study.
Pre- and postoperative angiograms of 100 consecutive patients with MCA aneurysms treated by craniotomy and clipping were compared to determine the postoperative incidence of changes involving the SMCV. CTs from the normal and abnormal postoperative venous groups were compared to determine the amount of edema or presence of parenchymal hemorrhage.
Postoperatively, 31 (31%) SMCVs were altered, 20 to a minor or moderate degree. Eleven cases were pronounced. In 9 (9%) cases, the SMCV was completely obscured or failed to fill on postoperative angiography. More edema (observer 1, P < .0002; observer 2, P < .0006) and small brain parenchymal hemorrhages (observer 1, P < .00003; observer 2, P < .00001) were found on the postoperative CT images of the group whose SMCVs were altered than those that were unchanged.
Neurosurgeons and neuroradiologists should be attentive to changes in the SMCV and adjacent venous structures to optimize outcomes of procedures involving the sylvian fissure.
A Six-Year-Old Girl With a Leukodystrophy Bodensteiner, John B., MD; Dean, Bruce, MD
Seminars in pediatric neurology,
03/2010, Letnik:
17, Številka:
1
Journal Article
Flood insurance payments can help households and businesses recover from an event and get the economy moving again. Premiums can also provide appropriate incentives to avoid or mitigate risk. This ...report examines dimensions of the changing flood insurance environment in New York City and explores the consequences for the city’s residents and businesses.
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