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111.
BACKGROUND: Aneurysmal degeneration of a carotid reconstruction was not recognized until the patient, who was known to have recurrent carotid artery stenosis, had a thromboembolic stroke. This sequelae of carotid endarterectomy is a serious complication, associated with a high morbidity and mortality rate. This review was conducted to establish the risk of transient ischemic attack and stroke for patients found to have recurrent carotid stenosis associated with aneurysmal degeneration of the carotid artery after endarterectomy. METHODS: A case is reported, and 100 literature references of aneurysmal degeneration of the carotid artery after endarterectomy were reviewed. RESULTS: False aneurysm from anastomotic disruption was the most common presentation identified in the cases reviewed. Nineteen of the patients had a significant neurologic event; however, three (50%) of six patients with aneurysm and recurrent carotid artery stenosis had a transient ischemic attack or stroke. CONCLUSIONS: The incidence of neurologic symptoms is markedly increased when recurrent carotid artery stenosis is associated with carotid aneurysm. During postoperative surveillance after endarterectomy, the identification of recurrent carotid artery stenosis requires evaluation for aneurysmal degeneration of the carotid artery with duplex scanning. These patients are at significant risk for transient ischemic attack and stroke. This rare complication merits operative repair. 相似文献
112.
113.
The influence of polymer surface-protein binding affinity on protein ion signals in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry is examined. The surfaces of poly(vinylidene fluoride) and poly(ethylene terephthalate) polymer substrates are modified by pulsed rf plasma deposition of allylamine. By varying the on/off duty cycle of the pulsed rf plasma, the polymer substrate surfaces are coated with thin films having varying densities of surface amine groups. The varying surface amine density is shown to lead to systematic changes in the surface binding affinity for the 125I-radiolabeled peptides angiotensin I and porcine insulin. Unlabeled angiotensin I and porcine insulin are then deposited on the pulsed rf plasma-modified substrates and analyzed by MALDI mass spectrometry. The experimental approach involves applying the peptide to the modified polymer surface in an aqueous phosphate-buffered saline solution and allowing the peptide solution to dry completely under ambient conditions. Subsequently, the MALDI matrix alpha-cyano-4-hydroxycinnamic acid in methanol and 10% trifluoroacetic acid in water are added to the peptide-coated modified polymer surfaces. The results of these studies demonstrate that, for the sample preparation method employed, increases in the surface peptide binding affinity lead to decreases in the peptide MALDI ion signal. 相似文献
114.
SG Willis KS Smith VL Dunn LA Gapter KH Riviere GR Riviere 《Canadian Metallurgical Quarterly》1999,37(3):867-869
Species-specific nested PCR was used to detect Treponema amylovorum, Treponema denticola, Treponema maltophilum, Treponema medium, Treponema pectinovorum, Treponema socranskii, and Treponema vincentii in dental plaque. Subjects with periodontitis harbored all species, but T. pectinovorum and T. vincentii were not found in plaque from disease-free subjects. 相似文献
115.
FJ Dilworth GR Williams AM Kissmeyer JL Nielsen E Binderup MJ Calverley HL Makin G Jones 《Canadian Metallurgical Quarterly》1997,138(12):5485-5496
116.
GR Hill JM Crawford KR Cooke YS Brinson L Pan JL Ferrara 《Canadian Metallurgical Quarterly》1997,90(8):3204-3213
The influence of bone marrow transplantation (BMT) conditioning regimens on the incidence and severity of graft-versus-host disease (GVHD) has been suggested in clinical BMT. Using murine BMT models, we show here an increase in GVHD severity in several donor-recipient strain combinations after intensification of the conditioning regimen by increasing the total body irradiation (TBI) dose from 900 cGy to 1,300 cGy. Increased GVHD was mediated by systemic increases in tumor necrosis factor alpha (TNF alpha). Histologic analysis of gastrointestinal tracts showed synergistic damage by increased TBI and allogeneic donor cells that permitted increased translocation of lipopolysacharide (LPS) into the systemic circulation. In vitro, LPS triggered excess TNF alpha from macrophages primed by the GVH reaction. In addition, macrophages isolated within 4 hours of conditioning were primed in proportion to the TBI dose itself to secrete TNF alpha. Thus, the higher TBI dose increased macrophage priming and increased gut damage after allogeneic BMT, causing higher systemic levels of inflammatory cytokines and subsequent severe GVHD. These data highlight the importance of conditioning in GVHD pathophysiology and suggest that interventions to prevent LPS stimulation of primed macrophages may limit the severity of GVHD after intensive conditioning for allogeneic BMT. 相似文献
117.
DJ Knapp AB Kampov-Polevoy DH Overstreet GR Breese AH Rezvani 《Canadian Metallurgical Quarterly》1997,21(7):1232-1240
To further understand the relationship between emotional state and alcohol intake in rats, the tendency to emit ultrasonic vocalizations in response to an aversive, but nonpainful, air puff stimulus was tested in several rat lines. Included in this group were Maudsley Reactive (MR) and Non-Reactive (MNR) rats, and several lines of rats with either high ethanol preference or a low ethanol preference: Preferring, (P), Alko-Alcohol (AA), and Fawn-Hooded (FH) animals; and Non-Preferring (NP), Alko-Non-Alcohol (ANA), and Flinders Resistant Line (FRL). MR rats emitted fewer ultrasonic vocalizations (USVs) and showed less preference for ethanol than did MNR animals. An overall analysis that included the P, NP, FH, FRL, AA, and ANA groups demonstrated a significant negative correlation between the total number of USVs emitted and ethanol consumption. NP, FRL, and especially ANA rats (low ethanol-preferring) emitted the most USVs--to an extent similar to that typically found for normal rats. The duration of vocalizing was higher only in the NP and the FRL rats the relative to their P and FH comparison groups, respectively. In the ethanol-preferring and nonpreferring lines, the numbers of USVs emitted correlated positively with the duration of vocalizing, but not with the latency to vocalize, which in turn did not correlate strongly with ethanol intake. The latency to vocalize did not correlate significantly with ethanol intake across all drinking lines or MR or MNR rats, but was found to be higher in FH and AA rats relative to their nondrinking comparison groups. These associations suggest that the relationship between emotional state and ethanol drinking is complex and cannot be attributed to a simple elevated state of anxiety or emotionality. Further examination of the central nervous system mechanisms mediating the difference in USVs between paired lines of ethanol-preferring and nonpreferring rats may identify neurochemical factors that predict ethanol preference. 相似文献
118.
GR Evans K Brandt KK Ang D Cromeens E Peden G Gherardini A Gurlek P Tinkey J Williams 《Canadian Metallurgical Quarterly》1997,100(2):375-380
Our purpose is to review recent data and provide a clinical opinion on the use of antibiotics to prevent preterm birth or related maternal-neonatal complications. A literature review and a synthesis of opinion are provided. During prenatal care, standard practices should be applied regarding Neisseria gonorrhoeae, Chlamydia trachomatis, and bacteriuria. In addition, screen for and treat bacterial vaginosis in patients at high risk for preterm birth but do not treat Ureaplasma urealyticum or group B streptococci genital colonization. With preterm labor and intact membranes, standard practices should be applied regarding group B streptococci prophylaxis. Do not give antibiotics routinely to prolong pregnancy, but in patients with bacterial vaginosis and Trichomonas vaginalis specific treatment should be given. With preterm premature rupture of membranes, standard practices should be applied regarding group B streptococci prophylaxis, but additional antibiotics should also be given to prolong pregnancies at 24 to 32 weeks' gestation. Reported adverse effects have been few to date. However, increased diligence is needed for resistant organisms. In selected clinical settings antibiotic therapy is now indicated to prolong pregnancy and prevent maternal-neonatal complications associated with preterm birth. 相似文献
119.
PS Cooke DL Buchanan P Young T Setiawan J Brody KS Korach J Taylor DB Lubahn GR Cunha 《Canadian Metallurgical Quarterly》1997,94(12):6535-6540
Estradiol-17beta (E2) acts through the estrogen receptor (ER) to regulate uterine growth and functional differentiation. To determine whether E2 elicits epithelial mitogenesis through epithelial ER versus indirectly via ER-positive stromal cells, uteri from adult ER-deficient ER knockout (ko) mice and neonatal ER-positive wild-type (wt) BALB/c mice were used to produce the following tissue recombinants containing ER in epithelium (E) and/or stroma (S), or lacking ER altogether: wt-S + wt-E, wt-S + ko-E, ko-S + ko-E, and ko-S + wt-E. Tissue recombinants were grown for 4 weeks as subrenal capsule grafts in intact female nude mice, then the hosts were treated with either E2 or oil a week after ovariectomy. Epithelial labeling index and ER expression were determined by [3H]thymidine autoradiography and immunohistochemistry, respectively. In tissue recombinants containing wt-S (wt-S + wt-E, wt-S + ko-E), E2 induced a similar large increase in epithelial labeling index compared with oil-treated controls in both types of tissue recombinants despite the absence of epithelial ER in wt-S + ko-E tissue recombinants. This proliferative effect was blocked by an ER antagonist, indicating it was mediated through ER. In contrast, in tissue recombinants prepared with ko-S (ko-S + ko-E and ko-S + wt-E), epithelial labeling index was low and not stimulated by E2 despite epithelial ER expression in ko-S + wt-E grafts. In conclusion, these data demonstrate that epithelial ER is neither necessary nor sufficient for E2-induced uterine epithelial proliferation. Instead, E2 induction of epithelial proliferation appears to be a paracrine event mediated by ER-positive stroma. These data in the uterus and similar studies in the prostate suggest that epithelial mitogenesis in both estrogen and androgen target organs are stromally mediated events. 相似文献
120.
Small cell tumors of the ovary are uncommon but represent an important group to recognize in the differential diagnosis of primary and metastatic ovarian neoplasms. In some cases the correct diagnosis cannot be confidently made on the basis of clinical setting, routine light microscopy, and immunohistochemistry, and electron microscopy may be supportive or definitive in establishing cell type. The cell type is often important in choosing optimal therapy and in predicting prognosis. The authors performed electron microscopy on a moderate number of ovarian small cell tumors and here describe and illustrate the diagnostic features of representative examples of various types. The ultrastructural features of the metastatic tumors, such as embryonal rhabdomyosarcoma, neuroblastoma, and melanoma, are identical to those of their respective primary tumors, are well known, and usually pose no problem in diagnosis. On the other hand, the ultrastructural features of some primary ovarian small cell tumors may present a more difficult differential diagnosis, because they have features that are subtle and/or in common. Exemplary of tumors in this category are diffuse adult granulosa cell tumor, endometrial stromal sarcoma, and small cell carcinomas of the hypercalcemic and pulmonary (oat cell) types. Distinguishing among them may be difficult but is possible, and electron microscopy may be a valuable supplement to the diagnostic information obtained from the clinical presentation, light microscopy, immunohistochemistry and, in some tumors, cytometric analysis of these neoplasms. 相似文献