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Operative
Terms modified by Operative Selected AbstractsLong-Term Results of Cardiac TransplantationJOURNAL OF CARDIAC SURGERY, Issue 3 2003Alberto Juffe M.D. From April 1991 to December 2000, 345 patients underwent heart transplantation at the Juan Canalejo Hospital. The mean age of recipients was54.5 ± 11.4 years; 286 (83%) were male patients. Idiopathic (52.2%) and ischemic (34.9%) end-stage cardiomyopathy were the main causes leading to transplantation. Ninety-four patients had undergone a previous heart operation. The mean left ventricular ejection fraction was22.8 ± 11.4. Forty patients (11.5%) were transplanted in urgent (status I) condition. The mean time spent on the waiting list was 35.9 days. In-hospital mortality was 10.6% and 24% for transplantations performed on an elective and urgent basis, respectively. Operative (30-day), one-year and six-year survival was 87.2%, 81.3% and 64%, respectively. In terms of actuarial survival, there were no significant differences with regard to the recipient's age, sex, previous cardiac surgery, and the etiology of the end-stage cardiomyopathy. The six-year actuarial survival for recipients receiving hearts from female donors was 59% compared with 72% for male donors(p = 0.05). There has been a low incidence of rejection, as well as cardiac graft vasculopathy. Actuarial survival at six years was 66% for patients transplantated on an elective basis compared with 57% for patients transplanted on an urgent basis(p = 0.04). The aim of the study was to evaluate long-term results for patients who underwent orthotopic heart transplantation. In our experience, status I is associated with a higher mortality.(J Card Surg 2003;18:183-189) [source] Impact of Perioperative Systemic Steroids on Surgical Outcomes in Patients With Chronic Rhinosinusitis With Polyposis: Evaluation With the Novel Perioperative Sinus Endoscopy (POSE) Scoring System,THE LARYNGOSCOPE, Issue S115 2007Erin D. Wright MDCM Abstract Objectives/Hypothesis: The objective of this randomized, double-blind, placebo-controlled study was to assess the effect of perioperative systemic steroids on subjective and objective surgical outcomes for patients undergoing endoscopic sinus surgery (ESS) for chronic rhinosinusitis with polyposis (CRSwP). The secondary objective was to begin validation of the newly developed Perioperative Sinus Endoscopy (POSE) scoring system. Methods: Patients who had failed maximal medical therapy and were scheduled to undergo ESS were eligible for the study. Participants were randomized to receive either 30 mg of prednisone or placebo for 5 days preoperatively and 9 days postoperatively. Operative and baseline clinical data were collected using the Lund-McKay staging system including its Sinus Symptom Questionnaire as well as additional data regarding mucosal health, the technical difficulty of surgery, and endoscopic data using the Lund-Kennedy Endoscopic Score (LKES) and POSE scale. Data were also collected at 2 weeks, 1 month, 3 months, and 6 months postoperatively. A sample size of 24 was calculated to detect a clinically relevant difference between groups of 40%. Routine statistical comparisons were performed as were repeated measures analysis of variance with Bonferroni adjustment because of the multiple comparisons performed. To address the secondary objective, data were also collected at all postoperative time points using the POSE instrument, which was designed with the intention of enhancing face validity and responsiveness to change. Comparisons were performed between the POSE and LKES, including assessment of sensitivity to change, correlation between the two scales, and correlation with symptom scores. Results: Twenty-six patients participated in the study. Operative data demonstrated a significantly higher percentage of severely inflamed sinonasal mucosa in patients not pretreated with systemic steroids, which was associated with technically more difficult surgery in the estimation of the operating surgeon. In terms of postoperative symptoms, there was no difference between treatment groups, with both placebo and prednisone significantly improved over baseline up to 4 weeks postoperatively. Endoscopic assessment of patients postoperatively demonstrated a treatment effect (P < .05), with clinically healthier cavities seen in patients treated with prednisone up to 6 months postoperatively as compared with baseline (P < .001), although the strongest effect was seen at the 2-week time point. In comparing the two endoscopic scales, the POSE and LKES correlated highly (R > 0.70; P < .001) both in terms of absolute score and change in score. There is some evidence that the POSE score may be more sensitive to change than the LKES, and the POSE scores did correlate more strongly with symptom scores than the LKES, although both endoscopic scores correlated only weakly with symptom scores. Conclusions: The data presented in this study support the practice of administering preoperative systemic steroids to patients undergoing ESS for CRSwP. Furthermore, in the practice of surgeons who provide intensive postoperative care post-ESS, including debridement and medical therapy based on the endoscopic findings, there is evidence to support administering systemic steroids in the postoperative period. The POSE scoring system compares favorably with the LKES and may confer advantages in terms of face/content validity and responsiveness to change and is worthy of further validation. [source] Contractual Limitations on the Auditor's Liability: An Uneasy Combination of Law and AccountingTHE MODERN LAW REVIEW, Issue 4 2009Article first published online: 1 JUL 200, P. E. Morris Operative as from 6 April 2008, sections 532,538 of the Companies Act 2006 create a new liability limitation regime in contractual relationships between audit firms and companies in relation to the statutory audit function which overturns an almost eighty years old fundamental principle of company law. This new regime is the product of continuing pressure by the audit profession for liability reform and concern by Government regarding the market structure for audit services. This commentary critically evaluates the regime from law and accounting perspectives. It concludes by reflecting on its longer term implications for audit quality, perceptions of the audit profession and the evolution of a future research agenda. [source] Protein kinases A and C stimulate the Na+ active transport in frog skeletal muscle without an appreciable change in the number of sarcolemmal Na+ pumpsACTA PHYSIOLOGICA, Issue 4 2005R. A. Venosa Abstract Aim:, The activation of both protein kinases A (PKA) and protein kinases C (PKC) in some cell types increases and in others reduces active Na+ efflux. These effects have been ascribed to either a change in the rate of ionic translocation by a fixed number of Na+ pumps or, a change in the number of plasma membrane pumps. The purpose of the present experiments was to study the effect of activating PKA and PKC on the Na+ extrusion by the Na+ pump in frog skeletal muscle. Methods:, Na+ (22Na+) fluxes and ouabain (3H-ouabain) binding were measured in frog sartorius muscles. Results:, Both activation of PKA and PKC increased the active Na+ extrusion by a factor of two; these effects were not additive. Ouabain binding experiments indicated that the pump stimulation by activation of these kinases is not associated with any significant increase in the number of plasma membrane pumps. Stimulation of the active Na+ efflux by protein kinase activation (no change in the number of sarcolemmal pumps) and by hypotonicity (increase in the number of pumps) could be elicited in the same preparation and they were additive. Conclusion:, It is concluded that in frog skeletal muscle fibres, (1) activation of both PKA and PKC stimulate the Na+ pump by increasing its rate of ionic translocation; and (2) two modes of Na+ active transport (with and without an increase in the number of pumps) are operative, and can be at work simultaneously, a phenomenon to be reckoned with. [source] Volume natriuresis vs. pressure natriuresisACTA PHYSIOLOGICA, Issue 4 2004P. Bie Abstract Body fluid regulation depends on regulation of renal excretion. This includes a fast vasopressin-mediated water-retaining mechanism, and slower, complex sodium-retaining systems dominated by the renin,angiotensin aldosterone cascade. The sensory mechanisms of sodium control are not identified; effectors may include renal arterial pressure, renal reflexes, extrarenal hormones and other regulatory factors. Since the pioneering work of Guyton more than three decades ago, pressure natriuresis has been in focus. Dissociations between sodium excretion and blood pressure are explained as conditions where regulatory performance exceeds the precision of the measurements. It is inherent to the concept, however, that sudden transition from low to high sodium intake elicits an arterial pressure increase, which is reversed by the pressure natriuresis mechanism. However, such transitions elicit parallel changes in extracellular fluid volume thereby activating volume receptors. Recently we studied the orchestration of sodium homeostasis by chronic and acute sodium loading in normal humans and trained dogs. Small increases in arterial blood pressure are easily generated by acute sodium loading, and dogs appear more sensitive than humans. However, with suitable loading procedures it is possible , also acutely , to augment renal sodium excretion by at least one order of magnitude without any change in arterial pressure whatsoever. Although pressure natriuresis is a powerful mechanism capable of overriding any other controller, it seems possible that it is not operative under normal conditions. Consequently, it is suggested that physiological control of sodium excretion is neurohumoral based on extracellular volume with neural control of renin system activity as an essential component. [source] COMPARISON OF THE HEIGHT OF PAPILLARY TUMOR IN INTRADUCTAL PAPILLARY MUCINOUS NEOPLASM OF THE PANCREAS BETWEEN MEASURED PREOPERATIVE IMAGES AND RESECTED MATERIALDIGESTIVE ENDOSCOPY, Issue 2006Kiyohito Tanaka The height of the mural nodules and papillary tumors in main pancreatic duct or dilated branch duct is the most important factor for diagnosis of intraductal papillary mucinous neoplasm (IPMN). In this study, the authors compared the height of the papillary lesions and mural nodules between the height of resected tissues and the height detected by the preoperative imaging tools (endoscopic ultrasonography [EUS] and intraductal ultrasonography [IDUS]) in 38 patients with IPMN. In 21 out of 23 cases of adenoma, and in cases with the non-invasive cancer, the difference of the height of operative and preoperative analysis measured by EUS and IDUS was within 1,2 mm. EUS and IDUS are useful for diagnosis of degree of malignancy in IPMN. [source] Diaconiae, xenodochia, hospitalia and monasteries: ,social security' and the meaning of monasticism in early medieval RomeEARLY MEDIEVAL EUROPE, Issue 4 2008Hendrik W. Dey The first section of this article examines the various types of charitable institutions operative in Rome between the seventh and the ninth centuries, in the light of what available textual and comparative evidence reveals about their respective functions. It is then suggested that these centres of assistance were staffed by resident monastic communities, an arrangement which accounts well for their many apparent similarities; which may help to explain the disappearance of the most commonly attested types (xenodochia and diaconiae) over the course of the ninth century; and which opens a window onto an alternative conception of monastic practice hitherto under-represented in the scholarly tradition. [source] The Assembling of Semiconductor NanocrystalsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 18 2005Alexey Shavel Abstract Recent accomplishments in arranging semiconductor nanoparticles in a desired manner are reviewed. Coupling mechanisms utilized for this purpose include electrostatic and covalent interactions, methods like layer-by-layer assembly, solvent-controlled precipitation and surface amination for covalent attachment of nanoparticles are employed. Dipole,dipole interactions are operative in nanocrystal solids and fast Förster energy transfer is observed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Modulation by adenosine of both muscarinic M1 -facilitation and M2 -inhibition of [3H]-acetylcholine release from the rat motor nerve terminalsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2002Laura Oliveira Abstract The crosstalk between adenosine and muscarinic autoreceptors regulating evoked [3H]-acetylcholine ([3H]-ACh) release was investigated on rat phrenic nerve-hemidiaphragm preparations. Motor nerve terminals possess facilitatory M1 and inhibitory M2 autoreceptors that can be activated by McN-A-343 (1,30 µm) and oxotremorine (0.3,100 µm), respectively. The muscarinic receptor antagonist, dicyclomine (3 nm,10 µm), caused a biphasic (inhibitory/facilitatory) effect, indicating that M1 -facilitation prevails during 5 Hz stimulation trains. Concomitant activation of AF,DX 116-sensitive M2 receptors was partially attenuated, as pretreatment with M1 antagonists, muscarinic toxin 7 (MT-7, 0.1 nm) and pirenzepine (1 nm), significantly enhanced inhibition by oxotremorine. Activation of A2A -adenosine receptors with CGS 21680C (2 nm) (i) potentiated oxotremorine inhibition, and (ii) shifted McN-A-343-induced facilitation into a small inhibitory effect. Conversely, the A1 -receptor agonist, R- N6 -phenylisopropyl adenosine (R-PIA, 100 nm), attenuated the inhibitory effect of oxotremorine, without changing facilitation by McN-A-343. Synergism between A2A and M2 receptors is regulated by a reciprocal interaction with facilitatory M1 receptors, which may be prevented by pirenzepine (1 nm). During 50 Hz-bursts, facilitation (M1) of [3H]-ACh release by McN-A-343 disappeared, while the inhibitory (M2) effect of oxotremorine became predominant. This muscarinic shift results from the interplay with A2A receptors, as it was precluded by the selective A2A receptor antagonist, ZM 241385 (10 nm). In conclusion, when the muscarinic M1 positive feedback loop is fully operative, negative regulation of ACh release is mediated by adenosine A1 receptors. During high frequency bursts, tonic activation of A2A receptors promotes M2 autoinhibition by braking the M1 receptor operated counteraction. [source] Cell proliferation and apoptosis: dual-signal hypothesis tested in tuberculous pleuritis using mycobacterial antigensFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 1 2004Sulochana D. Das Abstract Antigens and mitogens have the innate ability to trigger cell proliferation and apoptosis thus exhibiting a dual-signal phenomenon. This dual-signal hypothesis was tested with mycobacterial antigens (PPD and heat killed Mycobacterium tuberculosis, MTB) in tuberculous pleuritis patients where the immune response is protective and compartmentalized. We compared and correlated the cell-cycle analysis and antigen-induced apoptosis in normal and patients' peripheral blood mononuclear cells (PBMCs) and patients' pleural fluid mononuclear cells (PFMCs). In cell-cycle analysis, PFMCs showed good mitotic response with PPD and MTB antigens where 10% and 7% of resting cells entered the S and G2/M phases of cell cycle, respectively. This antigen-induced proliferation of PFMCs correlated well with the lymphocyte transformation test (LTT) results. On the other hand, PFMCs also showed 21% of spontaneous apoptosis, which further increased to 43%, by induction with known apoptotic agent like Dexamethasone (DEX) and the mycobacterial antigens PPD and MTB. Further we demonstrated by anti-CD3 induction experiments that prior activation of cells is prerequisite for them to undergo apoptosis. Our results showed that PPD and MTB antigens induced both cell proliferation and apoptosis in PFMCs, which were pre-sensitized to mycobacterial antigens in vivo. Thus the dual-signal phenomenon was operative against these antigens in tuberculous pleuritis. We also demonstrated that the activated cells are more predisposed to apoptosis. [source] Significant activity of a modified ribozyme with N7-deazaguanine at G10.1: the double-metal-ion mechanism of catalysis in reactions catalysed by hammerhead ribozymesGENES TO CELLS, Issue 8 2000Yuka Nakamatsu Background Several reports have appeared recently of experimental evidence for a double-metal-ion mechanism of catalysis in reactions catalysed by hammerhead ribozymes. In one case, hammerhead ribozyme-mediated cleavage was analysed as a function of the concentration of La3+ ions in the presence of a fixed concentration of Mg2+ ions so that the role of metal ions that are directly involved in the cleavage reaction could be monitored. The resultant bell-shaped curve for activation of cleavage was used to support the proposed double-metal-ion mechanism of catalysis. However, other studies have demonstrated that the binding of a metal ion (the most conserved P9 metal ion) to the pro-Rp oxygen (P9 oxygen) of the phosphate moiety of nucleotide A9 and to the N7 of nucleotide G10.1 is critical for efficient catalysis, despite the large distance (,20 Ĺ) between the P9 metal ion and the labile phosphodiester group in the ground state. In fact, it was demonstrated that an added Cd2+ ion binds first to the pro-Rp phosphoryl P9 oxygen but not with the pro-Rp phosphoryl oxygen at the cleavage site. Results In earlier discussions, it was difficult to completely exclude the possibility that La3+ ions might have replaced the P9 metal ion and, as a result, created conditions represented by the bell-shaped curve. In order to clarify this situation, we examined a chemically synthesized hammerhead ribozyme (7-deaza-R34) that included a minimal modification, namely, an N7-deazaguanine residue in place of G10.1. We compared the kinetic properties of this ribozyme with those of the parental ribozyme (R34). Kinetic analysis revealed that, unlike the cases of added Cd2+ ions, the added La3+ ions did not replace the pre-existing P9 metal ion, and that the replacement of N7 by C7 at G10.1 reduced the catalytic activity to a limited extent. This result indicates that the binding of a Mg2+ ion to N7 at G10.1 is catalytically important but not indispensable. Most importantly, 7-deaza-R34 also yielded a bell-shaped curve upon addition of La3+ ions to the reaction mixture. Conclusions Since the data based on our experiments with 7-deaza-R34 are completely free from potential artefacts, due to the binding of a La3+ ion to N7 at G10.1, our results, that 7-deaza-R34 yielded a bell-shaped curve following the addition of La3+ ions to the Mg2+ -background reaction mixture, strongly supports the proposal that a double-metal-ion mechanism is operative in the cleavage reaction which is catalysed by hammerhead ribozymes. [source] Social Security and Growth in an Altruistic EconomyGERMAN ECONOMIC REVIEW, Issue 1 2002Berthold U. Wigger This paper studies the macroeconomic impact of private and public intergenerational transfers in the presence of endogenous growth. It focuses on two-sided altruism implying that individuals have both a motive to make gifts to their parents and a motive to leave bequests to their children. The growth effects of social security depend on whether children are making gifts to their parents or parents are leaving bequests to their children. Which of the transfers is operative, in turn, depends on the size of social security benefits. Social security is legislated endogenously. The introduction of a social security program which definitely reduces per capita income growth and harms future generations is contemplated by altruistic individuals even if non-altruistic individuals disapprove it. [source] Geochemical Factors Controlling Radium Activity in a Sandstone AquiferGROUND WATER, Issue 4 2006Tim Grundl Geochemical processes behind the occurrence of radium activities in excess of the U.S. EPA's drinking water limit of 5 pCi/L combined radium were investigated in a regional sandstone aquifer located in southeastern Wisconsin. Geochemical speciation modeling (PHREEQC 2.7) combined with a detailed understanding of the regional flow system provided by recent flow modeling efforts was used to determine that radium coprecipitation into barite controls radium activity in the unconfined portion of the aquifer. As the aquifer transitions from unconfined to confined conditions, radium levels rise and the water becomes more sulfate rich yet the aquifer remains at saturation with barite throughout. Calculations based on published distribution coefficients and the observed Ra:Ba atomic ratios indicate that barite contains ,12 ,g/kg coprecipitated radium. Confined portions of the aquifer have high concentrations of sulfate, and barium concentrations become too low to be an effective control on radium activity. Additional, as yet undefined, controls on radium are operative in the downgradient, confined portion of the aquifer. [source] The Prevalence of Headache and Its Association With Socioeconomic Status Among Schoolchildren in Istanbul, TurkeyHEADACHE, Issue 5 2009Objective., The etiology and pathogenesis of migraine and other types of headache are still under discussion. An interaction of organic, psychological, and psychosocial factors is operative. In this study, we aimed to determine the prevalence of headache and its association with socioeconomic status among schoolchildren. Study Design., A cross-sectional study was performed on 2669 schoolchildren via a parental questionnaire. Socioeconomic status was determined according to the Turkish socioeconomic status scale. Results., The mean age of the students was 8.2 ± 2.4 years. The headache prevalence was 46.2% (95% CI: 44.3-48.1). The prevalence of migraine was 3.4% (95% CI: 2.8-4.1), the prevalence of probable migraine was 8.7% (95% CI: 7.6-9.8), and that of non-migraine headache was 34.1% (95% CI: 32.3-35.9). Multivariate analysis revealed that older age, being a girl, having a family history of headache, and exposure to passive smoking at home were independently associated with headache. There was an inverse association between socioeconomic status and all 3 types of headaches after adjusting for age, sex, family history of headache, and presence of passive smoking. When the group with the lowest socioeconomic status was taken as the reference category, the odds ratios for the highest socioeconomic group were 0.33 (95% CI: 0.16-0.69, P = .003) for the migraine, 0.30 (95% CI: 0.11-0.89, P = .029) for the probable migraine, and 0.34 (95% CI: 0.16-0.72, P = 0.005) for the non-migraine headache. Conclusion., Headache is more common among children with lower socioeconomic groups. Social causation can play a role in the pathogenesis of headache. [source] Diagnostic evaluation of cystic pancreatic lesionsHPB, Issue 1 2008B. C. VISSER Abstract Background. Cystic pancreatic neoplasms (CPNs) present a unique challenge in preoperative diagnosis. We investigated the accuracy of diagnostic methods for CPN. Material and methods. This retrospective cases series includes 70 patients who underwent surgery at a university hospital for presumed CPNs between 1997 and 2003, and for whom a definitive diagnosis was established. Variables examined included symptoms, preoperative work-up (including endoscopic retrograde cholangiopancreatography (ERCP) in 22 cases and endoscopic ultrasound (EUS) in 12), and operative and pathological findings. Preoperative computed tomography (CT) and magnetic resonance imaging (MRI) scans (n=50 patients; CT=48; MRI=13) were independently reviewed by two blinded GI radiologists. Results. The final histopathologic diagnoses were mucinous cystic neoplasm (n=13), mucinous cystadenocarcinoma (10), serous cystadenoma (11), IPMN (14), simple cyst (3), cystic neuroendocrine tumor (5), pseudocyst (4), and other (10). Overall, 25 of 70 were malignant (37%), 21 premalignant (30%), and 24 benign (34%). The attending surgeon's preoperative diagnosis was correct in 31% of cases, incorrect in 29%, non-specific "cystic tumor" in 27%, and "pseuodcyst vs. neoplasm" in 11%. Eight had been previously managed as pseudocysts, and 3 pseudocysts were excised as presumed CPN. In review of the CT and MRI, a multivariate analysis of the morphologic features did not identify predictors of specific pathologic diagnoses. Both radiologists were accurate with their preferred (no. 1) diagnosis in <50% of cases. MRI demonstrated no additional utility beyond CT. Conclusions. The diagnosis of CPN remains challenging. Cross-sectional imaging methods do not reliably give an accurate preoperative diagnosis. Surgeons should continue to err on the side of resection. [source] Biasing the organism for novelty: A pervasive property of the attention systemHUMAN BRAIN MAPPING, Issue 8 2010Qi Chen Abstract Although the functional and anatomical independences between the orienting and the executive attention networks have been well established, surprisingly little is known about the potential neural interaction between them. Recent studies point out that spatial inhibition of return (IOR), a mechanism associated with the orienting network, and nonspatial inhibition of return, a mechanism associated with the executive network, might bias the organism for novel locations and objects, respectively. By orthogonally combining the spatial and the nonspatial IOR paradigms in this fMRI study, we demonstrate that the orienting and the executive networks interact and compensate each other in biasing the attention system for novelty. Behaviorally, participants responded slower to the target at the old location only when the color of the target was novel, and participants responded slower to the old color representation only when the target appeared at a novel spatial location. Neurally, the orienting network was involved in slowing down responses to the old location only when the nonspatial IOR mechanism in the executive network was not operative (i.e., when the color of the target was novel); the prefrontal executive network was involved in slowing down responses to the old color representation only when the spatial IOR mechanism in the orienting network was not functioning (i.e., when the target appeared at a novel location). Hum Brain Mapp, 2010. © 2010 Wiley-Liss, Inc. [source] Attitudes and use of rubber dam by Irish general dental practitionersINTERNATIONAL ENDODONTIC JOURNAL, Issue 6 2007C. D. Lynch Abstract Aim, To investigate the attitudes towards and use of rubber dam by Irish general dental practitioners. Methodology, A pre-piloted questionnaire was distributed amongst a group of 600 dentists randomly selected from the Irish Register of Dentists. Replies from dentists working in specialist practice or the hospital dental service were excluded. Dentists were surveyed in relation to their use of rubber dam during a variety of operative and root canal treatments, as well as their attitudes to the use of rubber dam in dental practice. Results, A total of 300 replies were considered from a total of 324 that were received. Seventy-seven per cent of respondents (n = 231) worked in general dental practice and 23% (n = 69) worked in the Irish Health Board/Community Dental Service. Rubber dam was ,never' used by 77% of respondents (n = 228) when placing amalgam restorations in posterior teeth, 52% (n = 147) when placing composite restorations in posterior teeth, and 59% (n = 177) when placing composite restorations in anterior teeth. Rubber dam was ,never' used by 39% of respondents (n = 114) when performing root canal treatment on anterior teeth; 32% (n = 84) when performing root canal treatment on premolar teeth; and 26% (n = 51) when performing root canal treatment on molar teeth. Fifty-seven per cent (n = 171) considered rubber dam ,cumbersome and difficult to apply', and 41% (n = 123) considered throat pack ,as good a prevention against inhalation of endodontic instruments as rubber dam'. Conclusions, Whilst rubber dam is used more frequently for root canal treatment than operative treatment, its use is limited. This presents quality issues, as well as medico-legal and safety concerns for both the profession and patients. [source] How do COPD and healthy-lung patients tolerate the reduced volume ventilation strategy during OLV ventilation.ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2010P. MICHELET Background: Although a strategy of tidal volume (Vt) reduction during the one-lung ventilation (OLV) period is advised in thoracic surgery, the influence of the pre-operative respiratory status on the tolerance of this strategy remains unknown. Therefore, the aim of this study was to compare the pulmonary function between chronic obstructive pulmonary disease (COPD) and healthy-lung patients during the operative and the post-operative period. Methods: Forty-eight patients undergoing a planned lobectomy for cancer and presenting either a healthy lung function (n=24) or a moderate COPD stage (n=24) were ventilated without external positive end-expiratory pressure (PEEP) and received 9 ml/kg Vt during the two-lung ventilation (TLV) period, secondary reduced to 6 ml/kg during the OLV period. Lung function was assessed by peroperative gas exchange, venous admixture, respiratory mechanical parameters and post-operative spirometric measurements. Results: Although the PaO2 was superior in the healthy-lung group during the TLV, once the OLV was established, no difference was observed between the two groups. Moreover, the PaO2/FiO2 was proportionally more impaired in the healthy-lung group compared with the COPD group (50 ± 13 vs. 72 ± 19% of the baseline values after exclusion and 32 ± 15 vs. 51 ± 25% after the thoracotomy, P<0.05 for each) as well as the venous admixture. In the post-operative period, a higher decrease was observed in the healthy-lung group for the forced vital capacity and the forced expiratory volume. Conclusions: Reducing Vt to 6 ml/kg without the adjunction of external PEEP during OLV is associated with better preservation of lung function in the case of moderate COPD than in the case of healthy-lung status. [source] Perceived in-group and out-group stereotypes among Brazilian foreign language studentsINTERNATIONAL JOURNAL OF APPLIED LINGUISTICS, Issue 2 2001Linda Gentry El-Dash Our research over the past few years on the attitudes of Brazilians towards the English language suggests that socio-psychological and socio-cultural aspects of motivation may be just as operative in foreign language learning as in second language acquisition. This article presents the results of a study of stereotypical perceptions of ten foreign populations by 164 Brazilian university students studying diverse foreign languages. Socio-cultural stereotypes were investigated using bipolar adjective scales paired in a Likert-type format. A factor analysis of the revealed stereotypes suggested a three-factor system is at work, consisting of conscientiousness (work-related values), social agreeableness and personal warmth. Evidence was found for the hypothesis that students studying a foreign language tend to have relatively positive stereotypes of the speakers of that language, but the picture is quite complex, with attraction and stereotyping of target-language speakers being linked to two different sets of values within the Brazilian population studied. [source] The Glasgow Blatchford scoring system enables accurate risk stratification of patients with upper gastrointestinal haemorrhageINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 7 2010R. Srirajaskanthan Summary Background:, Upper gastrointestinal (UGI) haemorrhage is a frequent cause of hospital admission. Scoring systems have been devised to identify those at risk of adverse outcomes. We evaluated the Glasgow Blatchford score's (GBS) ability to identify the need for clinical and endoscopic intervention in patients with UGI haemorrhage. Methods:, A retrospective observational study was performed in all patients who attended the A&E department with UGI haemorrhage during a 12-month period. Patients were separated into low and high risk categories. High risk encompassed patients who required blood transfusions, operative or endoscopic interventions, management on high dependency or intensive care units, and those who re-bled, represented with further bleeding, or who died. Results:, A total of 174 patients were seen with UGI bleeding. Eight of them self-discharged and were excluded. Of the remaining 166, 94 had a ,low risk' bleed, and 72 ,high risk'. The GBS was significantly higher in the high risk (median = 10) than in the low risk group (median 1, p < 0.001). To assess the validity of the GBS at separating low and high risk groups, receiver-operator characteristic (ROC) curves were plotted. The GBS had an area under ROC curve of 0.96 (95% CI 0.95,1.00). When a cut-off value of , 3 was used, sensitivity and specificity of GBS for identifying high risk bleeds was 100% and 68%. Thus at a cut-off value of , 2 the GBS is useful for distinguishing those patients with a low risk UGI bleed. Conclusions:, The GBS accurately identifies low risk patients who could be managed safely as outpatients. [source] Perioperative fluid management: prospective auditINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 3 2008S. R. Walsh Summary Background:, Postoperative fluid management is a core surgical skill but there are few data regarding current fluid management practice and the incidence of potential fluid-related complications in general surgical units. We conducted a prospective audit of postoperative fluid management and fluid-related complications in a consecutive cohort of patients undergoing midline laparotomy. Methods:, Over a 6-month period, the peri-operative fluid management of 106 consecutive patients was prospectively audited. Serum electrolyte data, fluid balance data, co-morbidities, operative and anaesthetic variables and quantities of fluid and electrolytes prescribed were recorded. The development of fluid-related and other complications was noted. Results:, There were no correlations between routinely available fluid balance parameters and the quantities of fluid and electrolytes prescribed, suggesting that doctors do not consult fluid balance data when prescribing. Fifty-seven patients (54%) developed at least one fluid-related complication. These patients received significantly greater volumes of fluid and sodium each day postoperatively. They had higher rates of other non-fluid-related complications and death. They had a longer hospital stay. In a multivariate model, mean daily fluid load predicted the development of fluid-related complications. Conclusion:, Fluid prescription practice in general surgical units is sub-optimal, resulting in avoidable iatrogenic complications. Involvement of senior staff, education and possibly the introduction of prescribing protocols may improve the situation. [source] Complications and the learning curve for a laparoscopic nephrectomy at a single institutionINTERNATIONAL JOURNAL OF UROLOGY, Issue 2 2006TORU KANNO Background:, We assessed our experiences in performing a laparoscopic nephrectomy, with regard to complications and the learning curve, during a 4-year period. Methods:, Between November 2000 and October 2004, a total of 78 laparoscopic nephrectomies were performed at our institution (37 radical nephrectomies, 30 nephroureterectomies and 11 simple nephrectomies). The patient charts were retrospectively reviewed to identify any operative and postoperative complications, and also to evaluate the operating time. Results:, A total of eleven complications (14.1%) occurred in our series (nine operative and two postoperative complications). All operative complications were due to vascular injuries (n = 9), five (2.6%) of which required an open conversion. The operating time and the rates of complications decreased significantly as the surgeons' experiences increased. Conclusion:, A laparoscopic nephrectomy could be performed as safely as previously reported. In addition, the learning curve for a laparoscopic nephrectomy appeared to be good over the initial 50 procedures at our institution. [source] Radio-frequency ablation of renal cell carcinoma in patients who were at significant riskINTERNATIONAL JOURNAL OF UROLOGY, Issue 12 2004OSAMU UKIMURA Abstract, Objective:, Although radio-frequency ablation (RFA) has been recently applied as a minimally invasive treatment option for renal cell carcinoma (RCC), indication of this modality remains a critical issue due to the lack of complete tumor destruction as well as the uncertainty of its long-term efficacy. We report the efficacy of RFA for nine carefully selected patients with RCC who had significant reason to avoid invasive surgical treatment under general anesthesia. Methods:, Radio-frequency ablation was performed under epidural or local anesthesia by ultrasound or computed tomography (CT) guidance in nine patients with biopsy proven RCC (mean diameter, 38 mm; range, 20,53 mm), who were at significant operative or anesthetic risk for invasive surgery. Follow-up enhanced CT scans or magnetic resonance images were evaluated every 3,6 months and an evaluation of metastasis was performed every 6 months. Results:, At a mean follow-up of 17 months, seven (78%) of the nine patients with renal tumor showed no tumor enhancement. The renal function of all patients was well preserved. All patients were able to continue undergoing their respective treatments for active diseases in other organs in parallel to the RFA treatment. No distant metastasis, urine leakage were reported and one case of temporary hematuria and one case of peri-renal hemorrhage not requiring blood transfusion were encountered. Intra-operative ultrasonography was useful in the real-time monitoring of the minimally excessive extension of ablation into the normal parenchyma. Conclusion:, Radio-frequency ablation appears to be an effective and safe minimally invasive therapeutic option for selected patients with RCC who have reason to avoid invasive surgery under general anesthesia. [source] Decomposing the Value of Agricultural Multifunctionality: Combining Contingent Valuation and the Analytical Hierarchy ProcessJOURNAL OF AGRICULTURAL ECONOMICS, Issue 2 2007Zein Kallas Q18; Q11; Q25 Abstract Agricultural multifunctionality is the recognition of the joint exercise of economic, environmental and social functions by this sector. Nevertheless, not all these contributions to society are valued in markets, moreover a large share of them are public goods. For this reason, in order to make this concept of multifunctionality operative for the design of public policies, it is necessary to estimate the social demand of such functions. The objective of this article was to implement an empirical application along these lines. For this purpose, the agricultural system of cereal steppes in Tierra de Campos in Spain is taken as a case study. The economic valuation technique used relies on a combined implementation of contingent valuation and the analytical hierarchy process. The results obtained demonstrate the existence of a significant demand for the different attributes included in the multifunctionality concept, although this demand is heterogeneous and is based on the socioeconomic characteristics of individual persons. [source] Coronary Artery Bypass Surgery in Patients with Malignancy: A Single-Center Study with Comparison to Patients Without MalignancyJOURNAL OF CARDIAC SURGERY, Issue 2 2009Nezihi Kucukarslan M.D. In this study, we compared the outcome of coronary artery bypass graft (CABG) in such patients with those without malignancy. Methods: The patients were selected from those who had undergone coronary artery bypass surgery in the last decade. The study group (group I) included the patients with malignancy in remission. The control group comprised those patients who were selected randomly from those without any malignancy. The patients were retospectively examined with regard to preoperative, operative, and postoperative data from personal files, computerized recording system, and operation reports. Results: Group I included 48 patients (age 48 to 69; 29 male) while group II included 50 patients (age = 38 to 73; 35 male). In group I, comorbidity rates were: renal dysfunction in 12 (25%), obstructive lung disease 10 (21%), congestive failure in four (8%) patients. The malignancy rates were: lung in 15 (31%), breast in 10 (21%), stomach in five (10%), colon in four (8%), renal in one (2%), Hodgkin's lyphoma in three (6%), leukemia in two (4%), ovarian in three (6%), and prostate in five (10%) patients. In group II, the comorbidity rates were: diabetes mellitus 18 (36%), renal dysfunction in five (10%) and obstructive lung disease in 13 (26%) patients. In group I, chemotherapy and radiotherapy were performed in 38 and 34 patients, respectively. In groups I and II, the CABG was elective in 47 (98%) and in 45 patients (90%); the off-pump surgery was performed in 27 (56%) and 12 (24%) patients, respectively. The total duration of bypass was 37 ± 6 minutes and 44 ± 5 minutes; the duration of aortic clamp was 26 ± 4 and 29 ± 7 minutes, respectively, in groups I and II. Posoperative complication rates were: infection in 12 (25%), bleeding in eight (17%), acute renal insufficiency in eight (17%), prolonged air escape in five (10%), and prolonged entubation in 17 (35%) patients in group I and atrial fibrillation in 11 (22%) patients in group II. Mortality rates in both groups were two (4%). Conclusion: CABG in patients with comorbid malignancy is as safe as the other patients. In patients with full remission of malignancy, the surgeons should be encouraged about the safety of CABG. [source] Mitral Valve Replacements in Redo Patients with Previous Mitral Valve Procedures: Mid-Term Results and Risk Factors for SurvivalJOURNAL OF CARDIAC SURGERY, Issue 5 2008Tankut Hakki Akay M.D. Patients and Methods: Between September 1989 and December 2003, 62 redo patients have undergone mitral valve replacements due to subsequent mitral valve problems. Preoperative, operative, and postoperative data were analyzed retrospectively and evaluated for risk factors affecting hospital mortality, mid- and long-term survival. Results: The hospital mortality was 6.4%. The one-, five-, and 10-year actuarial survival rates were 94%± 2%, 89%± 6%, and 81 ± 9%. New York Heart Association (NYHA) functional class IV, low left ventricular ejection fraction (<35%), increased left ventricular end-diastolic diameter (LVEDD) > 50 mm, female gender, pulmonary edema, and urgent operations were found to be risk factors in short-term survival. NYHA functional class IV, low left ventricular ejection fraction, increased LVEDD, and increased left atrial diameter (LA > 60 mm) were risk factors in mid-term survival. Conclusion: Redo mitral valve surgery with mechanical prosthesis offers encouraging short- and mid-term survival. NYHA functional class IV, low left ventricular ejection fraction, and increased left ventricular diameters were especially associated with increased short- and mid-term mortality. Earlier surgical management before the development of severe heart failure and myocardial dysfunction would improve the results of redo mitral valve surgery. [source] Repair of Partial Atrioventricular Septal Defect Through a Minimal Right Vertical Infra-Axillary ThoracotomyJOURNAL OF CARDIAC SURGERY, Issue 3 2002Xiubin Yang M.D. Methods: From November 1997 to January 2000, six patients with a mean age of 19.2 ± 7.7 years underwent minimal right vertical infraaxillary thoracotomy (VIAT) for PAVSD repair. Left atrioventricular (AV) valve regurgitation was tested on the beating heart before and after valvuloplasty. Commissuroplasty of the left AV valve and atrial septum repair were done in all patients. Results: There was no operative or late mortality, and no morbidity directly related to the thoracotomy approach. The average length of the incision was 8.3 ± 1.3 cm. The arrest times averaged 32.8 ± 8.3 minutes, and the cardiopulmonary bypass times averaged 66.0 ± 9.0 minutes. One patient had mild-to-moderate left AV valve regurgitation postoperatively. All patients were free of symptoms during follow-up. Conclusion: Minimal right VIAT is a safe, more cosmetic, and less invasive approach than median sternotomy for the repair of PAVSD. [source] Mid-term Results of the Ross ProcedureJOURNAL OF CARDIAC SURGERY, Issue 4 2001Domenico Paparella M.D. Although the Ross procedure has been performed for over three decades, its role in the management of patients with aortic valve disease is not well established. This study reviews our experience with this operation. From 1990 to 1999, 155 patients underwent the Ross procedure. The mean age of 106 men and 49 women was 35 years. Most patients (85%) had congenital aortic valve disease. The pulmonary autograft was implanted in the subcoronary position in 2 patients, as an aortic root inclusion in 78, and aortic root replacement in 75. The follow-up extended from 9 to 114 months, mean of 45 ± 28 months, and it was complete. All patients have had Doppler echocardiographic studies. There was only one operative and one late death. The survival was 98% at 7 years. The freedom from 3+ or 4+ aortic insufficiency was 86% at 7 years and the freedom from reoperation on the pulmonary autograft was 95% at 7 years. Dilation of the aortic annulus and/or sinotubular junction was the most common cause of aortic insufficiency. One patient required three reoperations on the biological pulmonary valve. Most patients (96%) have no cardiac symptoms. The Ross procedure has provided excellent functional results in most patients, but progressive aortic insufficiency due to dilation of the aortic annulus and/or sinotubular junction is a potential problem in a number of patients. [source] Defining the transcriptome of accelerated and replicatively senescent keratinocytes reveals links to differentiation, interferon signaling, and Notch related pathways,JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 2 2006Ranjan J. Perera Abstract Epidermal keratinocytes (KCs) undergo highly orchestrated morphological and molecular changes during transition from proliferative compartment into growth arrested early and late differentiation layers, prior to dying in outermost cornified layers of normal skin. Creation of stratum corneum is vital to barrier function protecting against infection. Transcriptional events in KCs regulating complex processes of differentiation and host defense required to maintain constant epidermal thickness and resistance to infection in either young or aged skin are largely unknown. Furthermore, as terminal differentiation is characterized by irreversible loss of replicative potential culminating in dead layers at the skin surface, this process may be viewed as a form of senescence. However, a complete transcriptional profile of senescent (SN) human KCs has not been previously defined to permit delineation of molecular boundaries involving differentiation and senescence. To fill this void, we utilized global transcriptional analysis of KCs maintained in vitro as either cultures of proliferating (PR) cells, early and late confluent (LC) (accelerated senescence) cultures, or KCs undergoing replicative senescence. Global gene expression profiling revealed early confluent (EC) KCs were somewhat similar to PR KCs, while prominent differences were evident when compared to LC KCs; which were also distinct from replicatively SN KCs. While confluent KCs have in common several genes regulating differentiation with replicatively SN KCs, the latter cells expressed elevated levels of genes involved in interferon signaling and inflammatory pathways. These results provide new insights into cell autonomous transcriptional-based programs operative within KCs contributing to replicative senescence, with partial sharing of genes involved in differentiation. In addition, regulation of KC senescence may involve participation of interferon signaling pathways derived from the important role of KCs in protecting skin from infection. Integrating all of the transcriptional data revealed a key role for Notch receptor mediated signaling in the confluency induced differentiation phenotype using this model system. J. Cell. Biochem. 98: 394,408, 2006. © 2006 Wiley-Liss, Inc. [source] The existence of secondary orbital interactionsJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 1 2007Chaitanya S. Wannere Abstract B3LYP/6-311+G** (and MP2/6-311+G**) computations, performed for a series of Diels-Alder (DA) reactions, confirm that the endo transition states (TS) and the related Cope-TSs are favored energetically over the respective exo -TSs. Likewise, the computed magnetic properties (nucleus-independent chemical shifts and magnetic susceptibililties) of the endo - (as well as the Cope) TS's reveal their greater electron delocalization and greater aromaticity than the exo -TS's. However, Woodward and Hoffmann's original example is an exception: their endo -TS model, involving the DA reaction of a syn - with an anti -butadiene (BD), actually is disfavored energetically over the corresponding exo -TS; magnetic criteria also do not indicate the existence of SOI delocalization in either case. Instead, a strong energetic preference for endo -TSs due to SOI is found when both BDs are in the syn conformations. This is in accord with Alder and Stein's rule of "maximum accumulation of double bonds:" both the dienophile and the diene should have syn conformations. Plots along the IRC's show that the magnetic properties typically are most strongly exalted close to the energetic TS. Because of SOI, all the points along the endo reaction coordinates are more diatropic than along the corresponding exo pathways. We find weak SOI effects to be operative in the endo -TSs involved in the cycloadditions of cyclic alkenes, cyclopropene, aziridine, cyclobutene, and cyclopentene, with cyclopentadiene. While the endo -TSs are only slightly lower in energy than the respective exo -TSs, the magnetic properties of the endo -TS's are significantly exalted over those for the exo -TS's and the Natural Bond Orbitals indicate small stabilizing interactions between the methylene cycloalkene hydrogen orbitals (and lone pairs in case of aziridine) with ,-character and the diene , MOs. © 2006 Wiley Periodicals, Inc. J Comput Chem 2007 [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||