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51.
Recurrence of olfactory groove meningiomas 总被引:8,自引:0,他引:8
OBJECTIVE: Despite apparent gross total resection, olfactory groove meningiomas have a high rate of late recurrence (average, 23%). In this retrospective study, we confirmed that the sites of these recurrences are the cranial base and paranasal sinuses. We postulated that these recurrences stem from conservative handling of the underlying invaded bone. Therefore, we analyzed patient outcomes according to the radicality of surgical resection. METHODS: Fifteen consecutive patients with a diagnosis of olfactory groove meningioma were treated surgically between 1992 and 2001 (nine new cases, six recurrent). Only patients with benign meningiomas were included; atypical and malignant meningiomas were excluded. Surgical resection included the dura and drilling of the underlying bone and resection of involved mucosa. We reviewed each patient's clinical records, radiological studies, sites of recurrence, grade of previous resection, and complications. RESULTS: Olfactory groove meningiomas invaded the underlying bone in 13 cases. All patients with recurrence had previously undergone a surgical resection corresponding only to Simpson Grade 2, which does not include the removal of underlying invaded bone. The sites of recurrence were in the cranial base or adjacent paranasal sinuses. The time to recurrence varied from 1 to 12 years (average, 7 yr; mean, 8 yr). Three patients had undergone one previous resection, two had undergone two previous resections, and one had undergone four previous operations. The ethmoid sinus was involved in all cases of recurrence, either with the sphenoid sinus or with an intracranial recurrence. Thirteen patients underwent complete resection of underlying bone and the invaded paranasal sinuses, then reconstruction of the anterior fossa. No patient died. There were three instances of cerebrospinal fluid leakage (one requiring operative repair), one case of delayed worsening vision after initial improvement, and two cases of transient cranial nerve palsy (Cranial Nerves III and IV). There was no recurrence at follow-up (average, 3.7 yr; range, 1-7.3 yr). CONCLUSION: The cranial base and paranasal sinuses are sites of predilection for recurrence of olfactory groove meningiomas. Recurrence is the result of a direct extension attributable to incomplete resection of involved bone and regrowth at the edge of a previous surgical field. Extensive resection of all suspicious underlying bone is a complement to radical removal of these lesions. Reconstruction with a vascularized pericranial flap to prevent cerebrospinal fluid leakage is crucial. 相似文献
52.
Endotracheal intubation in the field does not improve outcome in trauma patients who present without an acutely lethal traumatic brain injury 总被引:6,自引:0,他引:6
OBJECTIVES: There is an absence of prospective data evaluating the impact of prehospital intubation in adult trauma patients. Our objectives were to determine the outcome of trauma patients intubated in the field who did not have an acutely lethal traumatic brain injury (death within 48 hours) compared with patients who were intubated immediately on arrival to the hospital. METHODS: Prospective data were collected on 191 consecutive patients admitted to the trauma center with a field Glasgow Coma Scale score < or = 8 and a head Abbreviated Injury Scale score > or = 3 who were either intubated in the field or intubated immediately at admission to the hospital. Patients who died within 48 hours of admission and transfers were excluded from the study. RESULTS: Of the 191 patients, 176 (92%) sustained blunt trauma and 25 (8%) were victims of penetrating trauma. Seventy-eight (41%) of the 191 patients were intubated in the field and 113 (59%) were intubated immediately at admission. There was no significant difference in age, Glasgow Coma Scale score, head Abbreviated Injury Scale score, or Injury Severity Score between the two groups. Patients who were intubated in the field had a significantly higher morbidity (ventilator days, 14.7 vs. 10.4; hospital days, 20.2 vs. 16.7; and intensive care unit days, 15.2 vs. 11.7) compared with patients intubated on immediate arrival to the hospital and nearly double the mortality (23% vs. 12.4). Field-intubated patients had a 1.5 times greater risk of nosocomial pneumonia compared with hospital-intubated patients. CONCLUSION: Prehospital intubation is associated with a significant increase in morbidity and mortality in trauma patients with traumatic brain injury who are admitted to the hospital without an acutely lethal injury. A randomized, prospective study is warranted to confirm these results. 相似文献
53.
Vlaming S Biehler A Hennessey EM Jamieson CP Chattophadhyay S Obeid OA Archer C Farrell A Durman K Warrington S Powell-Tuck J 《Clinical nutrition (Edinburgh, Scotland)》2001,20(6):517-526
BACKGROUND: Many patients admitted to acute hospital services are underweight or harbour vitamin deficiencies. OBJECTIVES: To determine the effect on patient throughput of a policy of routine vitamin supplementation, and of early routine sipfeed supplementation in 'thin' patients (5-10% weight loss or body mass index 18-22). DESIGN: Factorial randomized placebo controlled trial of oral multivitamins from the first day of admission, and, after nutritional screening, of a nutritionally complete sipfeed from the second day in 'thin' patients. SETTING: Acute medical, surgical and orthopaedic hospital services of a London teaching hospital. PARTICIPANTS: 1561 patients admitted as emergencies were included in the vitamin study of which 549 were included in the sipfeed study. MAIN OUTCOME MEASURE: Length of hospital stay (LOS). RESULTS: Offering multivitamins to acute admissions resulted in a mean change (reduction) in LOS of -0.4 days 95% CI (-2-1.2days). The results suggest greater reductions for those discharged after 10 days: mean change=-2.3 days 95% CI (-5.7 to 1.2). Sipfeed supplementation was associated with an increased mean length of stay 2.8 days 95% CI (-0.8-6.3). 18% of acute admissions were classified undernourished on the basis of BMI, MUAC or percent weight loss combined. CONCLUSIONS: No benefit was observed for sipfeed intervention although a small benefit of less than one day is not excluded. Vitamin supplementation may have slight but economically important benefit. 相似文献
54.
Nathalie Picollet-D'hahan Sophie Gerbaud Frédérique Kermarrec Jean-Pierre Alcaraz Patricia Obeid Ricky Bhajun Laurent Guyon Eric Sulpice Philippe Cinquin Monika E. Dolega Jayesh Wagh Xavier Gidrol Donald K. Martin 《Biomaterials》2013
The behaviour of cancerous epithelial prostatic cells (PC3) growing on polyelectrolytes (PE) coatings was compared to the behaviour of immortalized normal prostatic cells (PNT-2). The cell behaviour was evaluated and quantified in terms of initial cell attachment, growth, metabolic activity, morphometry, adhesion, apoptosis and stress related gene expression. Both the anionic PSS (poly(sodium 4-styrenesulphonate))-terminated surface and cationic PAH (poly(allylamine hydrochloride))-terminated surfaces were not cytotoxic. The initial attachment of cells was better on the PAH-terminated surface compared to fibronectin. However, the proliferation rate of PC3 cells was reduced on the PAH-terminated surface and slightly increased on the PSS coatings. Only PAH prevented the clustering phenotype of PC3 and reduced the number of focal adhesion points as compared to fibronectin or PSS coatings. In contrast, none of the PE surfaces significantly affected the biological responses of PNT-2 cells. PAH-terminating films provide a tool to preferentially modulate the growth of some cancerous phenotypes, in this case as a micro-environment that reduces the growth of metastatic PC3 cells. 相似文献
55.
Robert R. Burke Imad M. Obeid L. Keoki Williams Zachary Q. Morris 《The Journal of asthma》2013,50(7):740-744
Background. The 1999 American Thoracic Society methacholine challenge guidelines stated that the 5-breath dosimeter method of methacholine administration is similar to the 2-minute tidal breath method. Recent data has disputed this assertion. We examined the differences in the diagnosis of asthma using these two methods. Methods. Data were abstracted from a prospectively generated pulmonary function database over 4 years. During the first 2 years the 5-breath dosimeter method was used, and the subsequent 2 years the 2-minute tidal breath method was used. The effect of the delivery technique was assessed by crude and adjusted odds ratios, controlling for known confounders and group differences. Results. A total of 907 subjects underwent methacholine challenge testing during the 4-year study period: 19.3% of the subjects tested with the 5-breath dosimeter method and 31.2% of those tested with the 2-minute tidal breathing method had a PC20 ≤ 8.0 mg/mL (OR 1.90, 95% CI 1.4 to 2.58, p < 0.001). The ability to reliably exclude airway hyper-responsiveness (PC20 > 16.0 mg/mL) was also altered by the differences between the testing techniques. Using the 5-breath dosimeter method, 72.4% of subjects were ruled out for airway hyper-responsiveness, whereas only 59.9% of subjects were ruled out with the 2-minute tidal breathing technique (p < 0.001). Conclusion. The two recommended protocols for the diagnosis of asthma are not equivalent and significantly alter the rate of diagnosis of asthma as well as the severity. The differences were seen across all PC20 levels, from those with strongly positive tests (PC20 ≤ 1.0 mg/mL) as well as those with negative tests for airway hyper-responsiveness (PC20 > 16.0 mg/mL). 相似文献
56.
57.
Youssef E. Obeid DDS Carl F. Driscoll DMD Vincent J. Prestipino DDS 《Journal of prosthodontics》1999,8(3):160-162
A technique is described to help ensure the accurate reproduction of rigid implant components and the edentulous soft tissue. Splinted implant impression copings are luted together with resin to a specially designed custom tray. 相似文献
58.
59.
Five postoperative patients with respiratory failure and gram negative pneumonia unresponsive to systemic antimicrobials were treated with endotracheally instilled aminoglycosides. Sputum cultures in four patients grew Pseudomonas aeruginosa and, in the fifth, Enterobacter cloacae. The five patients had been treated systemically for an average of 13 days (range 9 to 19 days) without improvement prior to endotracheal antibiotic administration. The gram negative organisms disappeared from the sputum cultures in all patients within an average of 4 days (range 2 to 8 days) following initiation of endotracheal antibiotics. All five patients had continued clinical improvement manifest by improved chest radiographs, improved oxygenation, and absence of the offending organisms from sputum cultures. None of the patients died from their gram negative pneumonia. This success coupled with data from other investigators suggests that endotracheal antibiotics should be considered in life-threatening gram negative pneumonias that are unresponsive to conventional systemic antimicrobials. 相似文献
60.
Jürgen Geisel Ulrich Hübner Marion Bodis Heike Schorr Jean-Pierre Knapp Rima Obeid Wolfgang Herrmann 《Clinical chemistry and laboratory medicine》2003,41(11):1427-1434
Moderate hyperhomocysteinemia has been identified as a new independent risk factor for cardiovascular and neurodegenerative diseases. This fact has produced interest in the study of genetic variants involved in homocysteine metabolism and its relationship to pathogenesis. Recently, more than 15 different genes were studied for their relationship to plasma homocysteine levels. We determined the influence of genetic variants in five genes (5,10-methylenetetrahydrofolate reductase (MTHFR) 677C --> T, serine hydroxymethyltransferase (SHMT) 1420C --> T, thymidylate synthase (TS) 2R --> 3R, catechol-O-methyltransferase (COMT) 1947G --> A and transcobalamin (TC) 776C --> G) on plasma homocysteine, folic acid and parameters of vitamin B12 metabolism in 111 vegetarians (mean age: 46 +/- 15 years) and 118 healthy seniors (mean age: 82 +/- 6.5 years). Median homocysteine concentration in plasma was significantly influenced by the MTHFR genotypes in both populations. In the vegetarians the median homocysteine level was increased by 8 micromol/l in individuals homozygous for the mutation as compared to wild-type or heterozygous genotypes (20.4 micromol/l vs. 12.9 and 12.7 micromol/l, respectively). This unexpected increase was observed although the folate levels were in medium to elevated ranges. Our results suggest that vegetarians have a higher demand for folate to neutralize the genotype effect. Preclinical vitamin B12 deficiency in vegetarians may be the cause for disturbed remethylation and folate trap. Plasma homocysteine was not significantly influenced by the SHMT, TS, COMT and TC mutations. In addition, for the TC mutation a trend toward cellular vitamin B12 deficiency was observed. The methylmalonic acid (MMA) levels were slightly elevated and the holotranscobalamin-II (holoTC-II) levels decreased. In the vegetarian group a significant relationship between the COMT genotype and holoTC-II concentration in plasma was determined, whereas the high activity COMT genotype (G/G) resulted in increased levels (35 micromol/l vs. 21 micromol/l for heterozygous and low activity genotypes). The MMA levels were inversely correlated to holoTC-II concentrations. In conclusion, the study on vegetarians and seniors documents interesting lifestyle-genotype interactions. Although the TC and COMT mutations influence cellular vitamin B12 metabolism, this effect did not result in overt homocysteine elevation. 相似文献