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Loss Occurring (loss + occurring)
Selected AbstractsEtiology of Late Free Flap Failures Occurring After Hospital Discharge,THE LARYNGOSCOPE, Issue 11 2007Mark K. Wax MD Abstract Objectives: Vascular compromise of free flaps most commonly occurs in the immediate postoperative period in association with failure of the microvascular anastomosis. Rarely do flaps fail in the late postoperative period. It is not well understood why free flaps can fail after 7 postoperative days. We undertook a case review series to assess possible causes of late free flap failure. Study Design: Retrospective review at two tertiary referral centers: Oregon Health Sciences University and University of Alabama at Birmingham. Methods: A review of 1,530 flaps performed in 1,592 patients between 1998 and 2006 were evaluated to identify late flap failure. Late flap failure was defined as failure occurring after postoperative day 7 or on follow-up visits after hospital discharge. A prospective database with the following variables was examined: age, medical comorbidities, postreconstructive complications (fistula or infection), hematoma, seroma, previous surgery, radiation therapy, intraoperative findings at the time of debridement, nutrition, and, possibly, etiologies. Results: A total of 13 patients with late graft failure were identified in this study population of 1,530 (less than 1%) flaps; 6 radial forearm fasciocutaneous flaps, 2 rectus abdominis myocutaneous flaps, 4 fibular flaps, and 1 latissimus dorsi myocutaneous flap underwent late failure. The time to necrosis was a median of 21 (range, 7,90) days. Etiology was believed to possibly be pressure on the pedicle in the postoperative period in four patients (no sign of local wound issues at the pedicle), infection (abscess formation) in three patients, and regrowth of residual tumor in six patients. Loss occurring within 1 month was more common in radial forearm flaps and was presented in the context of a normal appearing wound at the anastomotic site, as opposed to loss occurring after 1 month, which happened more commonly in fibula flaps secondary to recurrence. Conclusion: Although late free flap failure is rare, local factors such as infection and possibly pressure on the pedicle can be contributing factors. Patients presenting with late flap failure should be evaluated for residual tumor growth. [source] EEG-fMRI of focal epileptic spikes: Analysis with multiple haemodynamic functions and comparison with gadolinium-enhanced MR angiogramsHUMAN BRAIN MAPPING, Issue 3 2004Andrew P. Bagshaw Abstract Combined EEG-fMRI has recently been used to explore the BOLD responses to interictal epileptiform discharges. This study examines whether misspecification of the form of the haemodynamic response function (HRF) results in significant fMRI responses being missed in the statistical analysis. EEG-fMRI data from 31 patients with focal epilepsy were analysed with four HRFs peaking from 3 to 9 sec after each interictal event, in addition to a standard HRF that peaked after 5.4 sec. In four patients, fMRI responses were correlated with gadolinium-enhanced MR angiograms and with EEG data from intracranial electrodes. In an attempt to understand the absence of BOLD responses in a significant group of patients, the degree of signal loss occurring as a result of magnetic field inhomogeneities was compared with the detected fMRI responses in ten patients with temporal lobe spikes. Using multiple HRFs resulted in an increased percentage of data sets with significant fMRI activations, from 45% when using the standard HRF alone, to 62.5%. The standard HRF was good at detecting positive BOLD responses, but less appropriate for negative BOLD responses, the majority of which were more accurately modelled by an HRF that peaked later than the standard. Co-registration of statistical maps with gadolinium-enhanced MRIs suggested that the detected fMRI responses were not in general related to large veins. Signal loss in the temporal lobes seemed to be an important factor in 7 of 12 patients who did not show fMRI activations with any of the HRFs. Hum. Brain Mapp. 22:179,192, 2004. © 2004 Wiley-Liss, Inc. [source] Regional variation of intracortical porosity in the midshaft of the human femur: age and sex differencesJOURNAL OF ANATOMY, Issue 2 2005C. David L. Thomas Abstract This study investigated age and sex differences in patterns of porosity distribution in the midshaft of the human femur. Cross-sections were obtained from 168 individuals from a modern Australian population. The sample comprised 73 females and 95 males, aged between 20 and 97 years. Microradiographs were made of 100-µm sections and pore and bone areas were determined using image processing software. Initially the sample was divided by age: young (20,44 years), middle (45,64 years) and old (65+ years), but it was found that analysis on the basis of the ratio of medullary area to total subperiosteal area gave clearer results. The cortex was divided into three rings radially and into octants circumferentially and the porosity of each segment was calculated. Results showed that a pattern with raised porosity in the posterior and anterolateral regions, and with greater porosity in the inner parts of the cortex, becomes more pronounced with age. In males this pattern develops steadily; in females there are much greater differences between the middle and older groups than earlier in life. The patterns observed are consistent with progressive bone loss occurring along a neutral axis of the cortex where bending stress is lowest and the mechanical advantage of the bone is least. [source] Synthesis and characterization of novel poly(arylene ether)s based on 9,10-bis-(4-fluoro-3-trifluoromethylphenyl) anthracene and 2,7-bis-(4-fluoro-3-trifluoromethylphenyl) fluoreneJOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2007Arun K. Salunke Abstract Two new bisfluoro monomers 9,10-bis-(4-fluoro-3-trifluoromethylphenyl) anthracene and 2,7-bis-(4-fluoro-3-trifluoromethylphenyl) fluorene have been synthesized by the cross-coupling reaction of 2-fluoro-3-trifluoromethyl phenyl boronic acid with 9,10-dibromo anthracene and 2,7-dibromo fluorine, respectively. These two bisfluoro compounds were used to prepare several poly(arylene ether)s by aromatic nucleophilic displacement of fluorine with various bisphenols; such as bisphenol-A, bisphenol-6F, bishydroxy biphenyl, and 9,9-bis-(4-hydroxyphenyl)-fluorene. The products obtained by displacement of the fluorine atoms exhibits weight-average molar masses up to 1.5 ×105 g mol,1 and number average molecular weight up to 6.8 × 104 g mol,1 in GPC. These poly(arylene ether)s show very high thermal stability even up to 490°C for 5% weight loss occurring at this temperature in TGA in synthetic air and showed glass transition temperature observed up to 310°C. All the polymers are soluble in a wide range of organic solvents, e.g., CHCl3, THF, NMP, and DMF. Films cast from DMF solution are brittle in nature. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 [source] Fresh insights into long-term changes in flora, vegetation, land use and soil erosion in the karstic environment of the Burren, western IrelandJOURNAL OF ECOLOGY, Issue 5 2009Ingo Feeser Summary 1. ,The study focuses on species-rich, upland, heathy vegetation with arctic-alpine floristic affinities and Sesleria grasslands in the karstic Burren region, western Ireland. The investigations aimed at reconstructing the long-term development of these high conservation-value communities and the role of farming in their formation and long-term survival. 2. ,The methods used included pollen analysis and 14C-dating of short monoliths and investigation of grykes (fissures in karstic limestone) for evidence of soil erosion. Special attention was paid to fossil, coprophilous fungal spores as indicators of local grazing. The strong local character of the pollen records facilitated identification of inter-site differences as well as regional patterns. It is shown that open pine woodland characterized the Cappanawalla uplands between c. 1500 BC and 500 BC. It is proposed that such woodlands, with floristic affinities to Scandinavian open pine woodlands on calcareous soils, provided a suitable environment for the present-day, open heath vegetation with species such as Dryas octopetala, Arctostaphylos uva-ursi, Geranium sanguineum and Empetrum nigrum. 3. ,Burning of vegetation as a management tool was important in the uplands over most of the last two millennia. Firing seems to have ceased with the onset of more intensive grazing regimes in the 18th century. 4. ,Synthesis. Upland palaeoarchives, derived from shallow peaty deposits, show that the upland Burren supported mainly plagioclimax Corylus -dominated woody vegetation and grasslands from c. 1500 BC (beginning of present record), until possibly as late as the 17th century AD. In the uplands of the north-western Burren, open, species-rich pinewoods with hazel dominated. The northern-arctic elements in the present-day upland flora survived clearances, involving initially Pinus sylvestris (c. 500 BC) and subsequently Corylus avellana (c. AD 1600). Colluvial material retrieved from grykes supports the idea of considerable soil loss occurring as late as the first and early 2nd millennium AD. The investigations highlight the potential of upland palaeoarchives, consisting of short sequences, for elucidating vegetation and land-use dynamics in karstic environments such as the Burren. [source] DE-310, a novel macromolecular carrier system for the camptothecin analog DX-8951f: Potent antitumor activities in various murine tumor modelsCANCER SCIENCE, Issue 2 2004Eiji Kumazawa DE-310 is a novel macromolecular conjugate composed of DX-8951f, a camptothecin analog, and a carboxymethyldextran polyalcohol carrier, which are covalently linked via a peptidyl spacer. In a murine Meth A (fibrosarcoma) solid tumor model, once daily×5 treatments (qd×5) with DX-8951f at the maximum tolerated dose (MTD) were required to shrink the tumor, and DX-8951f (qd×5) at 1/4 MTD was required to inhibit tumor growth. A single treatment (qd×1) with DE-310 at the MTD or 1/4 MTD shrank the tumor, with no body weight loss occurring at 1/4 MTD. Even at 1/16 MTD, DE-310 inhibited tumor growth. In a long-term assay, Meth A solid tumors disappeared in mice treated with DE-310 (qd×1) at the MTD and 1/2 MTD, and all 6 mice remained tumor-free on the 60th day after administration. Repeated injection (4 times) on schedules of every 3 days, 7 days or 14 days demonstrated that multiple treatment with DE-310 produced greater tumor growth delay than a single treatment with DE-310. Against 5 human tumor (colon and lung cancer) xenografts in mice, DE-310 (qd×1) was as effective as DX-8951f administered once every 4 days, 4 times. The life-prolonging activity of DE-310 was assessed in lung (3LL, Lewis lung carcinoma) and liver (M5076, histiocytoma) metastasis models. Against 3LL, DE-310 (qdx1) at the MTD to 1/3 MTD significantly prolonged survival, with an increase in life span (ILS) of 4.8- to 1.6-fold, respectively, over that in untreated control mice. Also, DE-310 (qd×1) significantly prolonged survival in the liver metastasis model of M5076. These results demonstrate that DE-310 is a promising agent for the treatment of cancer. [source] | |||||||||||||