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Terms modified by Definitive Selected AbstractsGASTRIC SCHWANNOMA WITH ADJACENT EXTERNAL PROGRESSION HARBORED ABERRANT NF2 GENEDIGESTIVE ENDOSCOPY, Issue 3 2009Naotaka Ogasawara Gastric schwannomas are rare benign mesenchymal tumors. We describe a schwannoma of gastric origin with adjacent external progression. Sections showed a spindle cell tumor arranged in interlaced bundles and fascicles that was S-100 and CD34 positive but c-KIT protein negative. Histology and immunohistochemistry revealed the typical appearance of a gastric schwannoma. Genetic evaluation revealed that the tumor harbored a point mutation in exon 6 of the tumor suppressor neurofibromatosis 2 (NF2) gene, which resulted in an amino acid substitution of NF2 protein, and no mutation in exon 4b of the NF1 gene. In conclusion, we identified a rare mutation of the NF2 gene in gastric schwannoma. A diagnosis can only be definitive when based on histological and immunohistochemical findings. Digestive tract schwannomas are rare mesenchymal tumors that are differentiated from gastrointestinal stromal tumors by the absence of KIT protein. Follow up suggested that complete resection is an effective long-term treatment strategy. [source] Dimensioning of secondary and tertiary control reserve by probabilistic methodsEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 4 2009Christoph Maurer Abstract Given the rising share of intermittent generation out of renewable energy sources on the one hand and the increased regulatory efforts to lower transmission costs and tariffs on the other hand, the optimal dimensioning of necessary control reserve has gained additional importance during the last years. Grid codes like the UCTE Operation Handbook do not provide definitive and unambiguous methods for dimensioning of secondary and tertiary control reserves. This paper therefore presents a method which calculates the necessary control reserve considering all important drivers for power imbalances like power plant outages, load variations and forecast error. For dimensioning, a probabilistic criterion, the accepted probability of insufficient control reserve, is used. Probability density functions of control area imbalances are calculated using a convolution algorithm. This paper provides analyses for a stylised example system to demonstrate the capabilities of the method. In a sensitivity analysis the impact of drivers like plant failures and forecast errors of load and generation is shown. The presented method is used by transmission system operators and regulatory authorities to determine and substantiate the necessary amount of control reserve. Copyright © 2009 John Wiley & Sons, Ltd. [source] MINIMAL SELFING, FEW CLONES, AND NO AMONG-HOST GENETIC STRUCTURE IN A HERMAPHRODITIC PARASITE WITH ASEXUAL LARVAL PROPAGATIONEVOLUTION, Issue 3 2006Charles D. Criscione Abstract Little is known about actual mating systems in natural populations of parasites or about what constitutes the limits of a parasite deme. These parameters are interesting because they affect levels of genetic diversity, opportunities for local adaptation, and other evolutionary processes. We expect that transmission dynamics and the distribution of parasites among hosts should have a large effect on mating systems and demic structure, but currently we have mostly speculation and very few data. For example, infrapopulations (all the parasites in a single host) should behave as demes if parasite offspring are transmitted as a clump from host to host over several generations. However, if offspring are well mixed, then the parasite component population (all the parasites among a host population) would function as the deme. Similarly, low mean intensities or a high proportion of worms in single infections should increase the selfing rate. For species having an asexual amplification stage, transmission between intermediate and definitive (final) hosts will control the variance in clonal reproductive success, which in turn could have a large influence on effective sizes and rates of inbreeding. We examined demic structure, selfing rates, and the variance in clonal reproductive success in natural populations of Plagioporus shawi, a hermaphroditic trematode that parasitizes salmon. Overall levels of genetic diversity were very high. An a posteriori inference of population structure overwhelmingly supports the component population as the deme, rather than individual infrapopulations. Only a single pair of 597 adult individuals was identified as clones. Thus, the variance in clonal reproductive success was almost zero. Despite being hermaphroditic, P. shawi appears to be almost entirely outcrossing. Genetic estimates of selfing (<5%) were in accordance with the proportion of parasites from single infections. Thus, it appears that individual flukes outcross whenever possible and only resort to selfing when alone. Finally, our data support the hypothesis that aquatic transmission and the use of several intermediate hosts promotes high genetic diversity and well-mixed infrapopulations. [source] Primary cancer of the sphenoid sinus,A GETTEC study,HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 3 2009Pierre Olivier Vedrine MD Abstract Background. Primary involvement of the sphenoid sinus occurs in 2% of all paranasal sinus tumors and is associated with dismal prognosis. Optimal management remains debatable. Methods. A total of 23 patients were treated for a primary cancer of the sphenoid sinus from 1988 to 2004. Charts were reviewed for patient-, tumor-, and treatment-related parameters. Univariate and multivariate analyses were conducted to identify prognostic factors for locoregional control and survival. Results. Cranial neuropathies were present in 12 patients. Pathologic findings included adenoid cystic carcinoma, adenocarcinoma, lymphoma, squamous cell carcinoma, sarcoma, neuroendocrine carcinoma, melanoma, and malignant hemangiopericytoma. All but 2 patients had stages III to IV cancer. Radiotherapy was performed in 18 patients and chemotherapy in 12. Of 10 patients undergoing surgery, total excision with grossly negative margins was achieved in 4 patients and subtotal resection in 6. Median locoregional control and overall survival were 12 and 41 months, respectively. On multivariate analysis, cranial neuropathy was associated with worse locoregional control and survival. Surgery was rarely complete because of advanced stages at presentation, but it yielded better outcomes than other treatments without surgery in non lymphoma-cases. Conclusion. Early CT and MRI should be performed when facing aspecific, rhinological, or neuro-ophtalmological symptoms. Cranial neuropathies indicate a worse prognosis. Surgery, including debulking surgery, may be preferred to combined modality treatments without surgery. Its apparently favorable impact on prognosis would need to be tested in homogenous histological groups of patients, which is impossible because of the rarity of the disease. Highly conformal radiotherapy (adjuvant or definitive) should be encouraged and optimized with concurrent chemotherapy in advanced stages. Aggressive multidisciplinary management including surgery, chemotherapy, and radiotherapy should be encouraged and adapted on histology and tumor extensions. Progress is still warranted to improve outcomes. © 2008 Wiley Periodicals, Inc. Head Neck, 2009 [source] Clinical impact of, and prognostic stratification by, F-18 FDG PET/CT in head and neck mucosal squamous cell carcinomaHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 11 2007Caroline A. Connell FRANZCR Abstract Background The aim of this study was to determine prospectively the incremental value of positron emission tomography/computed tomography (PET/CT) over conventional assessment (clinical examination and CT/MRI imaging). Methods All patients undergoing 18F-fluorodeoxyglucose (FDG)-PET/CT for primary head and neck mucosal squamous cell carcinoma between January 2002 and December 2003 (inclusive) were included in this study provided they had undergone contemporaneous conventional assessment of the head and neck region and had 12 months minimum follow-up. Results Seventy-six patients underwent 100 PET/CT scans. The majority of patients (74%) were treated with definitive (chemo)radiotherapy. Median follow-up time was 28 months. PET/CT led to a TNM classification alteration in 34% (12/35), a change in radiotherapy planning technique and/or dose in 29% (10/35), and altered treatment response assessment in 43% (13/30). A complete metabolic response was predictive of overall survival (p = .037). Conclusion Our results support incorporation of PET/CT into the management paradigm of head and neck mucosal squamous cell carcinoma. © 2007 Wiley Periodicals, Inc. Head Neck 2007 [source] Utility of positron emission tomography for the detection of disease in residual neck nodes after (chemo)radiotherapy in head and neck cancerHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 3 2005FRANZCR, Sandro V. Porceddu MBBS Abstract Background. This study evaluates the utility of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG PET) in patients with a node-positive mucosal head and neck squamous cell carcinoma who achieved a complete response at the primary site but had a residual mass in the neck 8 weeks or more after definitive (chemo)radiotherapy. Methods. Between October 1996 and July 2002, 39 eligible patients were identified. The reference PET scan was performed at a median of 12 weeks (range, 8,32 weeks) after treatment. Results. PET showed no metabolic activity in the residual mass in 32 patients. Five of these patients had a neck dissection and were all pathologically negative. The remaining 27 patients were observed for a median of 34 months (range, 16,86 months), with only one locoregional failure. The negative predictive value of PET for viable disease in a residual anatomic abnormality was 97%. Conclusion. Patients who have achieved a complete response at the primary site but have a residual abnormality in the neck that is PET negative approximately 12 weeks after treatment do not require neck dissection and can be safely observed. © 2004 Wiley Periodicals, Inc. Head Neck27: 175,181, 2005 [source] Predictive values for aspiration after endoscopic laser resections of malignant tumors of the hypopharynx and larynxHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 2 2004Manuel Bernal-Sprekelsen MD Abstract Background. CO2 -laser surgery is a relatively new treatment for selected carcinomas of the upper aerodigestive tract. The purpose of our study was to evaluate prospectively the functional results for swallowing after C02 -laser resections. Methods. The sample was composed of 210 consecutive patients with malignancies of the larynx and hypopharynx treated with CO2 laser between February 1998 and January 2002. Endoscopic resections included all T1 and T2 tumors and selected T3 and T4 tumors. T1 glottic tumors were not included in the analysis. We assessed the need for a feeding tube and the period the tube remained in place, aspiration pneumonia, tracheotomy secondary to aspiration, the need for a permanent or temporary gastrostomy, and total laryngectomy secondary to aspiration. Results. The nasogastric feeding tube was used in 23.2% of small tumors (2.5 ± 8.04 days) and in 63% of locally advanced tumors (13.95 ± 22.55 days). Frequency and period of storage of the feeding tube were higher in locally advanced tumors (p = .0001). Twelve patients (5.7%) had postoperative pneumonia and 59 (28.1%) had temporary postoperative cough during oral intake. Aspiration symptoms correlated with location (p = .001) and locally advanced tumors (p = .016). Eight patients (3.8%) needed a postoperative tracheotomy for severe swallowing difficulties; six (2.9%) of them were definitive and two (0.95%) temporary. Thirteen gastrostomies (6.2%) were performed to avoid severe aspirations; five of them were definitive. The need for gastrostomy correlated significantly with location (p = .002), pT3 and pT4 tumors (p = .002), age (p = .02), and postoperative radiotherapy (p = .04). No correlation was found with the period of feeding tube (p = .38), or aspiration pneumonia (p = .24). Conclusions. Endoscopic resection of laryngeal and hypopharyngeal tumors is associated with good recovery of deglutition. Many tracheotomies are avoided, the need for a feeding tube is usually reduced, and organ preservation is often feasible even in locally advanced tumors. © 2003 Wiley Periodicals, Inc. Head Neck26: 103,110, 2004 [source] Postradiotherapy surveillance practice for head and neck squamous cell carcinoma,too much for too little?,HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 12 2003David L. Schwartz MD Abstract Introduction. Limited information is available regarding surveillance patterns after head and neck cancer radiotherapy. We cataloged follow-up for a specified patient cohort treated at three neighboring university, community, and Veterans Administration institutions. Methods. One hundred fifteen patients were treated with curative intent between 1994,1998 with definitive or postoperative radiotherapy for newly diagnosed squamous cell carcinoma of the oral cavity, oropharynx, larynx, or hypopharynx. One hundred patients had continuous follow-up at their treating institution and were included for analysis. Median follow-up until disease recurrence or censorship was 28.5 months. Results. Median follow-up frequency was 5.7 visits/year and was highly variable. Although visit frequency correlated with disease stage and the presence of high-risk disease features, this association was lost when patients with early recurrences were removed from analysis. Procedure and test utilization closely mirrored visit frequency, resulting in a wide range of estimated yearly charges ($0,15,668/year; median, $1,772/year). Actuarial 3-year overall survival for the study group was 71%. Eighty-six percent (19 of 22) of potentially salvageable locoregional failures were discovered secondary to symptomatic complaint rather than by test results. Disease failure, whether detected by symptom or testing, predicted for poor survival (22% at 24 months after recurrence). Conclusions. Postradiotherapy surveillance for head and neck cancer is inconsistently pursued. A proven correlation between intensive follow-up and improved patient survival is lacking. Surveillance directed by patient symptoms should be investigated as an alternative approach. © 2003 Wiley Periodicals, Inc. Head Neck 25: 000,000, 2003 [source] What Are We Talking About?HYPATIA, Issue 4 2005Politics of Social Kinds, The Semantics Theorists analyzing the concepts of race and gender disagree over whether the terms refer to natural kinds, social kinds, or nothing at all. The question arises: what do we mean by the terms? It is usually assumed that ordinary intuitions of native speakers are definitive. However, I argue that contemporary semantic externalism can usefully combine with insights from Foucauldian genealogy to challenge mainstream methods of analysis and lend credibility to social constructionist projects. [source] Development of an ex vivo model for the study of microbial infection in human teethINTERNATIONAL ENDODONTIC JOURNAL, Issue 5 2007B. Patel Aims, (1) To infect human teeth artificially to mimic root canal and dentine infection, using the Constant Depth Film Fermenter (CDFF); (2) To verify the similarity of the infections to those found, in vivo, using culture and microscopy (SEM, LM and TEM). Methodology, Human teeth [n = 38 and n = 28, for phases I (preliminary) and II (definitive), respectively] were infected within the CDFF for a period of 28 days and at pre-selected time points were removed, externally decontaminated using validated protocols and subjected to either culture-dependent or microscopy protocols. The condition of the teeth was varied in phase I to establish the feasibility of the approach and identify optimal conditions. This informed the selection of optimal conditions for definitive test in phase II. For culture-dependent analysis in this phase, a dentine filing sample was obtained from the apical 5 mm of the root canal and cultured anaerobically to allow isolation of individual strains. Bacterial DNA was extracted from purified isolates, the 16S rRNA genes amplified by PCR and the amplicons sequenced for identity using sequence databases. Teeth assigned for microscopy were post-fixed in 3% gluteraldehyde after removal from the CDFF and then subjected to appropriate protocols prior to microscopic evaluation of the infection. Results, All three microscopy techniques and culture-dependent analysis confirmed infection of the human teeth using the CDFF, with root canal infections visually resembling closely those seen in vivo. Furthermore, partial 16S rRNA gene sequencing of DNA from cultured isolates confirmed a selective number of 7,9 genera/species in the apical portion of two teeth each at 7 and 28 days; these taxa are also commonly recovered from teeth with apical periodontitis, in vivo. There were no objective measures other than speciation and topographical evaluation to compare the artificial and real (in vivo) infections. Conclusions, The proposed ex vivo model has the potential for development into an investigative tool for studying the dynamics of bacterial ecology in infected root canals, both before and after treatment. Its advantage is the ability to control both the abiotic and biotic factors. There is a need for the development of objective measures to compare artificial and real bacterial biofilms. [source] Epidemiologic evaluation of pharmaceuticals with limited evidence of carcinogenicityINTERNATIONAL JOURNAL OF CANCER, Issue 9 2009Gary D. Friedman Abstract Thorough review by the International Agency for Research on Cancer (IARC) has resulted in classifying many substances, including pharmaceuticals, as probably or possibly carcinogenic to humans, based on experiments on animals or limited data on humans. We evaluated 9 such pharmaceuticals for evidence of carcinogenicity in patients receiving them in a large medical care program with automated pharmacy records and a cancer registry. Nested case,control analyses were performed in a cohort of 6.5 million subscribers with up to 12 years of follow-up, focusing on cancer sites suggested by previous evidence and other sites with odds ratio of at least 1.50, p < 0.01 and some evidence of dose,response. Unmeasured confounding was estimated in sensitivity analyses. We found some supportive evidence for carcinogenicity of griseofulvin, metronidazole and phenytoin and for the known carcinogen, cyclophosphamide, which was added for validation of our data and analyses. Findings for chloramphenicol, iron-dextran complex, phenoxybenzamine and phenobarbital were essentially non-contributory. Confounding by cigarette smoking and prior thyroid disease could account, respectively, for associations of oxazepam with lung cancer and propylthiouracil with thyroid cancer. Although not definitive, these findings should be considered in the evaluations of these pharmaceuticals. © 2009 UICC [source] Sensitising Concept, Themata and Shareness: A Dialogical Perspective of Social RepresentationsJOURNAL FOR THE THEORY OF SOCIAL BEHAVIOUR, Issue 3 2004LI LIU This article aims at clarifying some critical, yet under-explored, conceptual issues of social representations from a dialogical perspective. The article recasts the notion of social representations as a sensitising, rather than a definitive, concept, based on the distinction between dialogical and monological epistemologies. It is argued that the introduction of the concept of themata into the theory suggests the dialogical interdependence between common thinking and social morphology, between the genesis and structure of social representations, and between implicit underlying themata and their pragmatic manifestations in structuring social representations. At the same time, the concept of themata implies that a social representation may be, at one and the same time, shared and communicated in hegemonic, emancipated and polemical ways in a complementary manner. These three ways of "sharing" are dialogically interrelated to each other. [source] The Effect of Changing Practice on Fall Prevention in a Rehabilitative Hospital: The Hospital Injury Prevention StudyJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 3 2004Michael Vassallo FRCP Objectives: To determine whether a change in practice to introduce a multidisciplinary fall-prevention program can reduce falls and injury in nonacute patients in a rehabilitation hospital. Design: A quasi-experimental study. Setting: Three geriatric wards with a similar design, equipment, staffing levels, and skill mix. Participants: Eight hundred twenty-five consecutive patients. Intervention: The patients' fall-risk status was assessed using the Downton Score. Current practice was maintained on the two control wards (n=550). On the experimental ward (n=275), a fall-prevention program was introduced. A multidisciplinary team met weekly specifically to discuss patients' fall risk and formulate a targeted plan. Patients at risk were identified using wristbands; risk factors were corrected or environmental changes made to enhance safety. Measurements: Primary outcomes were number of fallers, recurrent fallers, total falls, patients sustaining injury, and falls per occupied bed days. Secondary outcomes were place of discharge and mortality. Results: Patients were matched for age and risk status. Control wards had proportionally more fallers (20.2% vs 14.2%: P=.033), patients sustaining injury (8.2% vs 4%: P=.025), and total number of falls (170 vs 72: P=.045). These results did not remain significant after controlling for differing length of stay. There was no reduction in recurrent fallers (6.4% vs 4.7%: P=.43) and no effect on place of discharge (home discharges; 57.5% vs 60.7%: P=.41) or mortality (15.3% vs 13.8%: P=.60). Conclusion: This study shows that falls might be reduced in a multidisciplinary fall-prevention program, but the results are not definitive because of the borderline significance achieved and the variable length of stay. More research on fall prevention in hospital is required, particularly as to what interventions, if any, are effective at reducing falls in this group of patients. [source] Evidence for a Single Nucleotide Polymorphism in the KCNQ1 Potassium Channel that Underlies Susceptibility to Life-Threatening ArrhythmiasJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 11 2001TOMOYUKI KUBOTA M.D. Ion Channel Polymorphism and Cardiac Arrhythmia. Introduction: Congenital long QT syndrome (LQTS) is a genetically heterogeneous arrhythmogenic disorder caused by mutations in at least five different genes encoding cardiac ion channels. It was suggested recently that common polymorphisms of LQTS-associated genes might modify arrhythmia susceptibility in potential gene carriers. Methods and Results: We examined the known LQTS genes in 95 patients with definitive or suspected LQTS. Exon-specific polymerase chain reaction single-strand conformation polymorphism and direct sequence analyses identified six patients who carried only a single nucleotide polymorphism in KCNQ1 that is found in , 11% of the Japanese population. This 1727G> A substitution that changes the sense of its coding sequence from glycine to serine at position 643 (G643S) was mostly associated with a milder phenotype, often precipitated by hypokalemia and bradyarrhythmias. When heterologously examined by voltage-clamp experiments, the in vitro cellular phenotype caused by the single nucleotide polymorphism revealed that G643S- KCNQ1 forms functional homomultimeric channels, producing a significantly smaller current than that of the wild-type (WT) channels. Coexpression of WT- KCNQ1 and G643S- KCNQ1 with KCNE1 resulted in , 30% reduction in the slow delayed rectifier K+ current IKs without much alteration in the kinetic properties except its deactivation process, suggesting that the G643S substitution had a weaker dominant-negative effect on the heteromultimeric channel complexes. Conclusion: We demonstrate that a common polymorphism in the KCNQ1 potassium channel could be a molecular basis for mild IKs dysfunction that, in the presence of appropriate precipitating factors, might predispose potential gene carriers to life-threatening arrhythmias in a specific population. [source] Clinical indicators of ineffective airway clearance in children with congenital heart diseaseJOURNAL OF CLINICAL NURSING, Issue 5 2009Viviane Martins Da Silva Aims and objectives., To analyse the sensitivity and specificity of clinical indicators of ineffective airway clearance in children with congenital heart disease and to identify the indicators that have high predictive power. Background., The precise establishment of nursing diagnoses has been found to be one of the factors contributing to higher quality of care and cost reduction in healthcare institutions. The use of indicators to diagnose ineffective airway clearance could improve care of children with congenital heart disease. Design., Longitudinal study. Methods., Participants consisted of 45 children, ,1 year of age, with congenital heart disease, who had not had definitive or palliative surgical correction. Six assessments were made at 2-day intervals. Each clinical indicator was defined based on previously established operational criteria. Sensitivity, specificity and positive and negative predictive values of each indicator were calculated based on a model for the longitudinal data. Results., A nursing diagnosis of ineffective airway clearance was made in 31% of patients on the first assessment, rising to 71% on the last assessment, for a 40% increase. Sensitivity was highest for Changes in Respiratory Rates/Rhythms (0·99), followed by Adventitious Breath Sounds (0·97), Sputum Production (0·85) and Restlessness (0·53). Specificity was higher for Sputum Production (0·92), followed by Restlessness (0·73), Adventitious Breath Sounds (0·70) and Changes in Respiratory Rates/Rhythms (0·17). The best positive predictive values occurred for Sputum Production (0·93) and Adventitious Breath Sounds (0·80). Conclusions., Adventitious Breath Sounds followed by Sputum Production were the indicators that had the best overall sensitivity and specificity as well as the highest positive predictive values. Relevance to clinical practice., The use of simple indicators in nursing diagnoses can improve identification of ineffective airway clearance in children with congenital heart disease, thus leading to early treatment of the problem and better care for these children. [source] Diagnosis of arterial occlusive disease of the upper extremities: Comparison of color duplex sonography and angiographyJOURNAL OF CLINICAL ULTRASOUND, Issue 8 2003Muharrem Tola MD Abstract Purpose The aim of this study was to assess the abilities of color duplex sonography (CDUS) to detect and characterize arterial occlusive disease of the upper extremities. Methods We prospectively compared the results of CDUS with those of intra-arterial digital subtraction angiography, which were considered definitive, in patients with symptomatic arterial occlusive disease of the upper extremities. In each extremity, we visualized 9 arterial segments, which were each evaluated for stenoses and occlusions. Each segment was categorized on each imaging modality as not significantly narrowed (narrowed by <50%), significantly narrowed (narrowed by ,50% but <100%), or occluded (100%). Results We examined a total of 578 segments in 57 patients (34 men and 23 women) with a mean age of 50 years (range, 20,74 years). CDUS had a sensitivity, a specificity, a positive predictive value, a negative predictive value, and an accuracy of 98%, 99%, 97%, 99.5%, and 99%, respectively, for detecting occluded lesions and 79%, 100%, 100%, 99%, and 99%, respectively, for detecting hemodynamically significantly stenotic lesions. Notably, the sensitivity of CDUS for diagnosing significantly stenotic lesions (79%) was lower than that for diagnosing occlusive disease (98%). Conclusions With high sensitivity and accuracy rates, CDUS is a reliable screening method for detecting arterial occlusive disease of the upper extremities. This modality efficiently provides anatomic and hemodynamic data that are useful in cases of such disease. © 2003 Wiley Periodicals, Inc. J Clin Ultrasound 31:407,411, 2003 [source] Two-dimensional and three-dimensional sonography of conjoined twinsJOURNAL OF CLINICAL ULTRASOUND, Issue 2 2002Fernando Bonilla-Musoles MD Abstract Purpose The aim of this study was to evaluate and compare the diagnostic capabilities of 2-dimensional (2D) and 3-dimensional (3D) sonography for the study of conjoined twins. Methods Four pregnant women with an initial 2D sonographic diagnosis of conjoined twins were examined with color Doppler sonography, 3D multiplanar sonography, and orthogonal plane imaging and 3D surface rendering. Results All 4 cases of conjoined twins were initially diagnosed with either transvaginal or transabdominal 2D sonography. 3D sonography afforded more realistic views and demonstrated more clearly the linking areas and surface anomalies, but 2D and color Doppler sonography provided more definitive and specific information about shared organs. Conclusions Although 2D sonography is the primary modality for diagnosing and evaluating conjoined twins, color Doppler and 3D sonography can sometimes provide additional information that assists in the clinical management of these twins. 3D sonography also provides images that are easier for parents to understand, which can help them with decision making. © 2002 John Wiley & Sons, Inc. J Clin Ultrasound 30:68,75, 2002; DOI 10.1002/jcu.10035 [source] Cutaneous squamous cell carcinoma: a comprehensive clinicopathologic classificationJOURNAL OF CUTANEOUS PATHOLOGY, Issue 4 2006Part Two Cutaneous squamous cell carcinoma (SCC) includes many subtypes with widely varying clinical behaviors, ranging from indolent to aggressive tumors with significant metastatic potential. However, the tendency for pathologists and clinicians alike is to refer to all squamoid neoplasms as generic SCC. No definitive, comprehensive clinicopathological system dividing cutaneous SCCs into categories based upon their aggressiveness has yet been promulgated. Therefore, we have proposed the following based upon the malignant potential of SCC variants, separating them into categories of low (,2% metastatic rate), intermediate (3,10%), high (greater than 10%), and indeterminate behavior. Low-risk SCCs include SCC arising in actinic keratosis, HPV-associated SCC, tricholemmal carcinoma, and spindle cell SCC (unassociated with radiation). Intermediate-risk SCCs include adenoid (acantholytic) SCC, intraepidermal epithelioma with invasion, and lymphoepithelioma-like carcinoma of the skin. High-risk subtypes include de novo SCC, SCC arising in association with predisposing factors (radiation, burn scars, and immunosuppression), invasive Bowen's disease, adenosquamous carcinoma, and malignant proliferating pilar tumors. The indeterminate category includes signet ring cell SCC, follicular SCC, papillary SCC, SCC arising in adnexal cysts, squamoid eccrine ductal carcinoma, and clear-cell SCC. Subclassification of SCC into these risk-based categories, along with enumeration of other factors including tumor size, differentiation, depth of invasion, and perineural invasion will provide prognostically relevant information and facilitate the most optimal treatment for patients. [source] Cutaneous squamous cell carcinoma: a comprehensive clinicopathologic classification.JOURNAL OF CUTANEOUS PATHOLOGY, Issue 3 2006Part One However, the tendency for pathologists and clinicians alike is to refer to all squamoid neoplasms as generic SCC. No definitive, comprehensive clinicopathological system dividing cutaneous SCCs into categories based upon their aggressiveness has yet been promulgated. Therefore, we have proposed the following based upon the malignant potential of SCC variants, separating them into categories of low (,2% metastatic rate), intermediate (3,10%), high (greater than 10%), and indeterminate behavior. Low-risk SCCs include SCC arising in actinic keratosis, HPV-associated SCC, tricholemmal carcinoma, and spindle cell SCC (unassociated with radiation). Intermediate-risk SCCs include adenoid (acantholytic) SCC, intraepidermal epithelioma with invasion, and lymphoepithelioma-like carcinoma of the skin. High-risk subtypes include de novo SCC, SCC arising in association with predisposing factors (radiation, burn scars, and immunosuppression), invasive Bowen's disease, adenosquamous carcinoma, and malignant proliferating pilar tumors. The indeterminate category includes signet ring cell SCC, follicular SCC, papillary SCC, SCC arising in adnexal cysts, squamoid eccrine ductal carcinoma, and clear-cell SCC. Subclassification of SCC into these risk-based categories, along with enumeration of other factors including tumor size, differentiation, depth of invasion, and perineural invasion will provide prognostically relevant information and facilitate the most optimal treatment for patients. [source] Cutaneous squamous cell carcinoma: a comprehensive clinicopathologic classificationJOURNAL OF CUTANEOUS PATHOLOGY, Issue 3 2006David S. Cassarino However, the tendency for pathologists and clinicians alike is to refer to all squamoid neoplasms as generic SCC. No definitive, comprehensive clinicopathological system dividing cutaneous SCCs into categories based upon their aggressiveness has yet been promulgated. Therefore, we have proposed the following based upon the malignant potential of SCC variants, separating them into categories of low (,2% metastatic rate), intermediate (3,10%), high (greater than 10%), and indeterminate behavior. Low-risk SCCs include SCC arising in actinic keratosis, HPV-associated SCC, tricholemmal carcinoma, and spindle cell SCC (unassociated with radiation). Intermediate-risk SCCs include adenoid (acantholytic) SCC, intraepidermal epithelioma with invasion, and lymphoepithelioma-like carcinoma of the skin. High-risk subtypes include de novo SCC, SCC arising in association with predisposing factors (radiation, burn scars, and immunosuppression), invasive Bowen's disease, adenosquamous carcinoma, and malignant proliferating pilar tumors. The indeterminate category includes signet ring cell SCC, follicular SCC, papillary SCC, SCC arising in adnexal cysts, squamoid eccrine ductal carcinoma, and clear-cell SCC. Subclassification of SCC into these risk-based categories, along with enumeration of other factors including tumor size, differentiation, depth of invasion, and perineural invasion will provide prognostically relevant information and facilitate the most optimal treatment for patients. [source] Testing for Potential Contextual Bias Effects During the Verification Stage of the ACE-V Methodology when Conducting Fingerprint Comparisons,JOURNAL OF FORENSIC SCIENCES, Issue 3 2009Glenn Langenburg M.Sc. Abstract:, This study was conducted to assess if fingerprint specialists could be influenced by extraneous contextual information during a verification process. Participants were separated into three groups: a control group (no contextual information was given), a low bias group (minimal contextual information was given in the form of a report prompting conclusions), and a high bias group (an internationally recognized fingerprint expert provided conclusions and case information to deceive this group into believing that it was his case and conclusions). A similar experiment was later conducted with laypersons. The results showed that fingerprint experts were influenced by contextual information during fingerprint comparisons, but not towards making errors. Instead, fingerprint experts under the biasing conditions provided significantly fewer definitive and erroneous conclusions than the control group. In contrast, the novice participants were more influenced by the bias conditions and did tend to make incorrect judgments, especially when prompted towards an incorrect response by the bias prompt. [source] Trace Element Fingerprinting of Australian Ocher Using Laser Ablation Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) for the Provenance Establishment and Authentication of Indigenous Art,JOURNAL OF FORENSIC SCIENCES, Issue 4 2007Rachel L. Green B.Sc. Abstract:, The expansion of indigenous art and the interest it has generated both at a domestic and international level means large monetary transactions are taking place between art galleries or centers and purchasers. As such, an accurate and conclusive method for provenance determination of traditional indigenous artistic materials must be established that can, if necessary, be used to assist in authentication of artworks. Laser ablation inductively coupled plasma mass spectrometry was utilized for elemental differentiation and provenance establishment of ocher samples. This research was used to develop a robust scientific protocol which facilitates definitive and accurate determination of provenance of Australian ochers and the artworks created using them. Analysis of the results obtained through this study show that the trace metal distribution patterns alone appear to be sufficient evidence to establish provenance of specific ochers, although additional differentiation between ocher samples, using major element distribution patterns, was achieved through the utilization of X-ray analytical techniques. [source] Bank Security Dye Packs: Synthesis, Isolation, and Characterization of Chlorinated Products of Bleached 1-(methylamino)anthraquinoneJOURNAL OF FORENSIC SCIENCES, Issue 6 2006James M. Egan Ph.D. ABSTRACT: Banknote evidence is often submitted after a suspect has attempted to disguise or remove red dye stain that has been released because of an anti-theft device that activates after banknotes have been unlawfully removed from bank premises. Three chlorinated compounds have been synthesized as forensic chemical standards to indicate bank security dye bleaching as a suspect's intentional method for masking a robbery involving dye pack release on banknotes. A novel, facile synthetic method to provide three chlorinated derivatives of 1-(methylamino)anthraquinone (MAAQ) is presented. The synthetic route involved Ultra CloroxÔ bleach as the chlorine source, iron chloride as the catalyst, and MAAQ as the starting material and resulted in a three-component product mixture. Two mono-chlorinated isomers (2-chloro-1-(methylamino)anthraquinone and 4-chloro-1-(methylamino)anthraquinone) and one di-chlorinated compound (2,4-dichloro-1-(methylamino)anthraquinone) of the MAAQ parent molecule were detected by gas chromatography mass spectrometry (GC-MS), and subsequently isolated by liquid chromatography (LC) with postcolumn fraction collection. Although GC-MS is sensitive enough to detect all of the chlorinated products, it is not definitive enough to identify the structural isomers. Liquid-state nuclear magnetic resonance (NMR) spectroscopy was utilized to elucidate structurally the ortho- and para-mono-chlorinated isomers once enough material was properly isolated. A reaction mechanism involving iron is proposed to explain the presence of chlorinated MAAQ species on stolen banknotes after attempted bleaching. [source] MR-guided biopsy of musculoskeletal lesions in a low-field systemJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 5 2001Claudius W. Koenig MD Abstract Thirty magnetic resonance (MR)-guided biopsies were obtained from 20 skeletal and 10 soft-tissue lesions in 31 patients using an open 0.2 T MR system equipped with interventional accessories. The results from aspiration (N = 3), core biopsy (N = 15), and transcortical trephine biopsy (N = 12) were evaluated for accuracy and clinical efficacy. Specimens were successfully obtained from 29 patients. Results were clinically effective in 23 patients, rated definitive in 16, nonconclusive in 9, and unspecific in 2 patients. A false diagnosis due to sampling error occurred in 2 patients, and biopsy sampling was impossible in one case. The best diagnostic yield was achieved from nontranscortical biopsies of osteolytic or soft-tissue masses. Results from transcortical biopsies were less specific due to the predominance of benign lesions. MR fluoroscopy for needle guidance was applied in 13 patients. Complete needle placement inside the magnet could be performed in 16 patients. MR-guided biopsy using an open low-field MR imager is feasible and clinically effective and will become a valuable tool in the management of musculoskeletal lesions. J. Magn. Reson. Imaging 2001;13:761,768. © 2001 Wiley-Liss, Inc. [source] Early cervical cancer treated with definitive or adjuvant radiotherapy: Improved survival with adjuvant radiotherapy attributable to patient selectionJOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 3 2003Craig A MacLeod Summary The optimum management of patients with early cervical cancer (Federation Internationale de Gynécologie Stages IB and IIA) remains controversial. We reviewed our radiotherapy practise and compared patients with early stage cervical cancer who had surgery and adjuvant radiotherapy (ART) to those that had definitive radiotherapy (DRT). One hundred and twenty-seven patients were identified, 81 of these underwent ART and 46 underwent DRT. Patients who underwent DRT were significantly older and of poorer performance status than those who underwent ART. The 5-year relapse-free survival in the ART and DRT groups were 79 and 72%, respectively (P = 0.70). The corresponding 5-year overall survival figures were 86 and 58% (P = 0.006). The difference was due to increased deaths from other causes in the DRT arm, 37 versus 7% (P = 0.0007.) The poorer overall survival of DRT patients was due to patient selection. [source] Petrogenetic significance of orthopyroxene-free garnet + clinopyroxene + plagioclase ± quartz-bearing metabasites with respect to the amphibolite and granulite faciesJOURNAL OF METAMORPHIC GEOLOGY, Issue 1 2003D. R. M. Pattison Abstract Orthopyroxene-free garnet + clinopyroxene + plagioclase ± quartz-bearing mineral assemblages represent the paragenetic link between plagioclase-free eclogite facies metabasites and orthopyroxene-bearing granulite facies metabasites. Although these assemblages are most commonly developed under P,T conditions consistent with high pressure granulite facies, they sometimes occur at lower grade in the amphibolite facies. Thus, these assemblages are characteristic but not definitive of high pressure granulite facies. Compositional factors favouring their development at amphibolite grade include Fe-rich mineral compositions, Ca-rich garnet and plagioclase, and Ti-poor hornblende. The generalized reaction that accounts for the prograde development of garnet + clinopyroxene + plagioclase ± quartz from a hornblende + plagioclase + quartz-bearing (amphibolite) precursor is Hbl + Pl + Qtz=Grt + Cpx + liquid or vapour, depending on whether the reaction occurs above or below the solidus. There are significant discrepancies between experimental and natural constraints on the P,T conditions of orthopyroxene-free garnet + clinopyroxene + plagioclase ± quartz-bearing mineral assemblages and therefore on the P,T position of this reaction. Semi-quantitative thermodynamic modelling of this reaction is hampered by the lack of a melt model and gives results that are only moderately successful in rationalizing the natural and experimental data. [source] Repeal of the Estate Tax and Its Impact on PhilanthropyNONPROFIT MANAGEMENT & LEADERSHIP, Issue 2 2001Patrick M. Rooney The estate tax has many advocates and opponents. We present a review of the primary arguments and empirical evidence promulgated in support of continuation and for repeal. Overall, we find that there are plausible theories and strong, but not definitive, empirical evidence on both sides of the issue. Further research is needed that more clearly isolates differences between the income-tax and estate-tax (that is, the after-tax cost or "price" of a donation or bequest) effects, the independent-income and wealth effects (how having higher income or wealth has an effect on giving during life and at death), and married and single estate tax filers. These differences can be best isolated using longitudinal data. Data and analyses for both the short run and long run are necessary before society can reasonably predict the impact the repeal of the estate tax will have on both giving during life and charitable bequests. [source] Perils of proximity: a spatiotemporal analysis of moral distress and moral ambiguityNURSING INQUIRY, Issue 4 2004Elizabeth Peter The physical nearness, or proximity, inherent in the nurse,patient relationship has been central in the discipline as definitive of the nature of nursing and its moral ideals. Clearly, this nearness is in service to those in need of care. This proximity, however, is not unproblematic because it contributes to two of the most prolonged difficulties, both for individual nurses and the discipline of nursing , moral distress and moral ambiguity. In this paper we explore proximity using both a moral and geographical lens and offer some insights regarding this practice reality. We examine the effect of proximity to patients on nurses' moral responsiveness, particularly as it affects nurses' moral distress. Proximity is paradoxical in this regard because, while it propels nurses to act, it can also propel nurses to ignore or abandon. Likewise, we argue that nursing's tendency to define itself in relation to the closeness of the nurse,patient relationship leads to problems of moral ambiguity. Our recommendations include moving others closer to the bedside and thus to the work of nursing in the literal and theoretical sense. [source] Electrophysiologicai Characteristics of the Atrium in Sinus Node Dysfunction With and Without Postpacing Atrial FihriliationPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 3 2000ANTONIO DE SISTI DE SISTI, A., ET AL.: Electrophysiologicai Characteristics of the Atrium in Sinus Node Dysfunction With and Without Postpacing Atrial Fibrillation . In patients with sinus node dysfunction (SND) with or without associated paroxysmal atrial fibrillation (AF), the effectiveness of atrial pacing in reducing the incidence of AF is not definitive. In addition, despite several studies involving large populations of implanted patients, little attention has been paid to the electrophysioiogicai (EP) atrial substrate and the effect of permanent atrial pacing. The aim of this study is to correlate EP data and the risk of AF after DDD device implantation. We reviewed FP data of 38 consecutive patients with SND. mean age 70 ± 8 years, who were investigated free of antiarrhythmic treatment, for the evaluation of the atrial substrate. We also considered as control group 25 subjects, mean age 63 ± 14 years, referred to our EP laboratory for unexplained syncope or various atrioventricular disturbances. Following pharmacological washout and at a drive cycle length of 600 ms. effective and functional refractory periods (ERP, FRP), Sl-Al and S2-A2 latency, Al and A2 conduction duration, and latent vulnerability index (EHP/A2) were measured. AF induction was tested with up to three extrastimuli at paced cycle lengths of 600 and 400 ms in 20 patients. Induction of sustained AF (> 30 seconds) was considered as the endpoint. P wave duration on the surface ECG in lead II/Vl was also measured. DDD pacing mode was chosen in all patients with the minimal atrial rate programmed between 60 and 75 beats/min (mean 64 ± 4 beats/min). After implantation, the patients were followed-up for 29 ± 17 months and clinically documented occurrence of AF was determined. When comparing patients with SND and subjects of the control group, we did not find any significant statistical differences in terms of ERP (237 ± 33 vs 250 ± 29 ms), FRP (276 ± 30 vs 280 ± 32 ms) and Sl-Al (39 ± 16 vs 33 ± 11 ms) and S2-A2 latency (69 ± 24 vs 63 ± 25 ms). In contrast, we observed significant differences regarding Al (55 ± 19 vs 39 ± 13 ms; P < 0.001), A2 (95 ± 34 vs 57 ± 18 ms; P < 0.001) and P wave duration (104 ± 18 vs 94 ± 15 ms; P < 0.05), and ERP/A2 (2.8 ± 1.2 vs 4.8 ± 1.6; P < 0.001). When comparing patients with (n = 11) or without (n =27) postpacing AF occurrence, we did not find any difference with reference to ERP, FRP. Sl-Al, S2-A2, Al duration, or follow-up duration. In patients with postpacing AF occurrence, A2 was longer (116 ± 41 vs 87 ± 27 ms; P < 0.01), FRP/A2 lower (2.1 ± 0.4 vs 3.1 ± 1.4; P < 0.05), P wave more prolonged (116 ± 22 vs 99 ± 14 ms; P < 0.01), and preexisting AF history predominant (6/11 vs 5/27 patients; P < 0.05). No difference was observed between patients with (n = 8) and without (n = 12) AF induction during the EP study. In patients with SND, the atrial refractoriness appears normal and the most important abnormality concerns conduction slowing disturbances. Persistence of AF despite pacing stresses the importance of mechanisms responsible for AF not entirely brady-dependent. In this setting, more prolonged atrial conduction disturbances, responsible for a low vulnerability index, and a preexisting history of AF enable us to identify a high risk patient group for AF in the follow-up. sinus node dysfunction, atrial fibrillation, electrophysiologicai study, atrial pacing [source] Raised intracranial pressure in a neonate presenting as stridorPEDIATRIC ANESTHESIA, Issue 8 2006KATE SOLAN FRCA Summary Neonatal stridor is an important sign of upper airway obstruction. This is most commonly secondary to laryngeal pathology and investigated by otolaryngologists. However neurological causes of stridor, secondary to vocal cord paralysis also occur for a variety of reasons (1). In cases of meningomyelocele up to 20% of infants may develop stridor (2). Respiratory distress may be severe and require prompt surgical and medical intervention. We describe a neonate born with a meningomyelocele, who developed stridor secondary to evolving hydrocephalus after surgical repair of the meningomyelocele. This was treated acutely by direct tapping of cerebrospinal fluid from the right coronal horn via the coronal suture with immediate symptomatic improvement prior to a definitive shunt procedure. [source] |