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High Propensity (high + propensity)
Selected AbstractsMicrocystic Adnexal Carcinoma: A Case Series Treated with Mohs Micrographic Surgery and Identification of Patients in Whom Paraffin Sections May Be PreferableDERMATOLOGIC SURGERY, Issue 4 2010IOULIOS PALAMARAS MD BACKGROUND Microcystic adnexal carcinoma (MAC) is a rare cutaneous tumor characterized by aggressive local infiltration, including a high propensity for perineural invasion (PNI). OBJECTIVES To report our experience in treating MAC using Mohs micrographic surgery (MMS) with frozen sections and to identify patients in whom that technique may have limitations. MATERIALS & METHODS A review of records between 1992 and 2008. RESULTS Nine patients with MAC were identified. All tumors were located on the face. PNI was noted in the diagnostic biopsies of two patients with periocular MAC, in both of whom tumor persisted after MMS. The mean duration of follow-up was 5.4 years. CONCLUSIONS MMS with frozen sections is reliable for treating primary MAC in which PNI is not present on a diagnostic biopsy. Previous surgery and PNI were associated with greater risk of persistence in periocular MAC. In these patients, it may be appropriate to consider MMS with paraffin-embedded sections, possibly as a layer after apparent clearance on frozen sections. Further excision of orbital contents should be considered in periocular MAC that infiltrate the deep orbital fat or are noted to have PNI. The authors have indicated no significant interest with commercial supporters. [source] Shwachman,Diamond syndrome with late-onset neutropenia and fatal acute myeloid leukaemia without maturation: a case reportEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 5 2003Jean-François Lesesve Abstract: We report on a male patient affected by Shwachman Diamond syndrome (SDS) who presented an unusual delayed neutropenia and then developed a poorly differentiated acute myeloid leukaemia (M0-AML) with trilineage myelodysplasia in adulthood. Conventional cytogenetics revealed complex karyotypic changes (monosomies 20, 21, 22, additional 15p). The patient was treated with conventional chemotherapy but never reached complete remission of leukaemia and died 18 months after diagnosis. SDS is an inherited bone marrow failure syndrome with a high propensity to leukaemic transformation. Since neutropenia may be intermittent or with delayed onset, and leukaemic transformation may not occur until adulthood, full blood count should be regularly monitored in such patients. [source] Suppression of HCV-specific T cells without differential hierarchy demonstrated ex vivo in persistent HCV infectionHEPATOLOGY, Issue 6 2003Kazushi Sugimoto Hepatitis C virus (HCV) has a high propensity for persistence. To better define the immunologic determinants of HCV clearance and persistence, we examined the circulating HCV-specific T-cell frequency, repertoire, and cytokine phenotype ex vivo in 24 HCV seropositive subjects (12 chronic, 12 recovered), using 361 overlapping peptides in 36 antigenic pools that span the entire HCV core, NS3-NS5. Consistent with T-cell-mediated control of HCV, the overall HCV-specific type-1 T-cell response was significantly greater in average frequency (0.24% vs. 0.04% circulating lymphocytes, P = .001) and scope (14/36 vs. 4/36 pools, P = .002) among the recovered than the chronic subjects, and the T-cell response correlated inversely with HCV titer among the chronic subjects (R = ,0.51, P = .049). Although highly antigenic regions were identified throughout the HCV genome, there was no apparent difference in the overall HCV-specific T-cell repertoire or type-1/type-2 cytokine profile relative to outcome. Notably, HCV persistence was associated with a reversible CD4-mediated suppression of HCV-specific CD8 T cells and with higher frequency of CD4+CD25+ regulatory T cells (7.3% chronic vs. 2.5% recovered, P = .002) that could directly suppress HCV-specific type-1 CD8 T cells ex vivo. In conclusion, we found that HCV persistence is associated with a global quantitative and functional suppression of HCV-specific T cells but not differential antigenic hierarchy or cytokine phenotype relative to HCV clearance. The high frequency of CD4+CD25+ regulatory T cells and their suppression of HCV-specific CD8 T cells ex vivo suggests a novel role for regulatory T cells in HCV persistence. [source] Therapy of acute hepatitis CHEPATOLOGY, Issue S1 2002Professor Alfredo Alberti M.D. Acute hepatitis C has a high propensity to become chronic, which provides the rationale for treating patients with acute disease attempting to prevent chronicity. Almost all published studies on therapy of acute hepatitis C have been small in size, uncontrolled, and highly heterogeneous as to patient features, dose and duration of treatment, follow-up evaluation, and criteria used to define efficacy and safety. The published studies on treatment of acute hepatitis C have used standard alfa or beta interferon monotherapy: none have evaluated combination therapy of interferon and ribavirin or peginterferon. Several meta-analyses of published studies have concluded that initiation of interferon monotherapy during the acute phase of hepatitis C virus (HCV) infection significantly reduces (by 30% to 40%) evolution to chronic hepatitis. The tolerability of interferon in acute hepatitis C has been excellent, even in symptomatic and icteric patients; the side effects and adverse events being similar in type and frequency to those seen when treating chronic cases. Thus, currently available data support treatment of patients with acute hepatitis C, but data are insufficient to draw firm conclusions about which patients to treat, when therapy should be started, or what regimen is optimal. Future studies of adequate size and design should focus on efficacy and tolerability of peginterferons and whether therapy should be started immediately after diagnosis or delayed for 2 to 4 months to avoid treatment of patients who spontaneously recover. (HEPATOLOGY 2002;36:S195-S200). [source] Increased expression of SDF-1/CXCR4 is associated with lymph node metastasis of invasive micropapillary carcinoma of the breastHISTOPATHOLOGY, Issue 6 2009Fangfang Liu Aims:, Stromal cell-derived factor-1 (SDF-1) and its receptor CXCR4 are implicated in tumour chemotaxis and metastasis. The aim was to examine their roles in the metastasis of invasive micropapillary carcinoma (IMPC) of the breast, a tumour with a high propensity for nodal spread. Methods and results:, We compared the expression of SDF-1 and CXCR4 in 103 cases of breast cancer containing IMPC components with a control group of 96 cases of invasive ductal carcinoma (IDC), not otherwise specified type by immunohistochemistry and chemical in situ hybridization (CISH). The results showed that the predominant cytoplasmic expression of both SDF-1 and CXCR4 was greater in tumour cells of the IMPC components than in those of the non-IMPC components and the control IDC cases, and was correlated significantly with the number of positive lymph nodes (P < 0.05). SDF-1 expression on cell membranes was less frequently identified in IMPC than IDC (P = 0.021). Immunohistochemical detection of SDF-1 in endothelial cells of lymphatic vessels was more common in IMPC (P = 0.007) and correlated significantly with lymph node status (P = 0.002), although SDF-1 mRNA was rarely detected by CISH. Conclusions:, This study suggests that up-regulation of cytoplasmic expression of SDF-1/CXCR4 might be one of the molecular mechanisms facilitating lymph node metastasis of IMPC. [source] Age-related histopathological lesions in the Mongolian gerbil ventral prostate as a good model for studies of spontaneous hormone-related disordersINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 1 2008Silvana Gisele Pegorin Campos Summary The Meriones unguiculatus (Mongolian) gerbil has demonstrated significant prostatic responses to hormonal treatments, and to drugs against human prostatic hyperplasia Spontaneous neoplasia develops in the older animals. Thirty gerbils (age 18 months) were divided into non-affected and prostatic lesion bearers and the prostate lesions were evaluated morphologically, immunohistochemically and quantitatively. The most frequent changes were in epithelial sites and, namely prostatic intraepithelial neoplasias, microinvasive carcinomas and adenocarcinomas. In the stromal compartment, cellular hyperplasia, when verified, was always associated with the sites of anomalous epithelium. Additionally, larger deposition of collagen fibrils, generating stromal fibrosis, was found in all the old gerbils analysed. The quantitative analysis showed that prostatic tissue proportions differed in altered areas, being specific for each lesion type. Isolated nuclear and nucleolar parameters were not effective in diagnosing the malign potential of lesions. However, the cellular proliferation and death indexes indicated larger cellular turnover in invasive lesions such as carcinomas. With these analyses, it could be verified that old gerbils present high propensity to develop spontaneous prostate changes and this may aid in a better understanding of the biological behaviour of human prostate cancer. [source] A sociodental approach to assessing dental needs of children: concept and modelsINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 2 2006S. GHERUNPONG Summary. Objectives., Traditional normative methods of assessing dental needs do not correspond to current concepts of ,health' and ,need'. Although there is dental research on quality of life, evidence-based practice, and oral behaviours, those concepts are rarely applied to dental needs estimation. Dental needs are usually calculated mainly from clinical data and are likely to be inaccurate. A structured comprehensive method for assessing dental needs is required. The objectives of this study are to develop and test a new sociodental system of needs assessment for overall dental needs of primary schoolchildren. Furthermore, normative and sociodental estimates of need are compared. Design., The study developed a theoretical framework and pathway algorithms of sociodental needs assessment and applied them to assessing overall dental needs. Normative dental needs were assessed using standard normative criteria. The child oral impacts on daily performances (Child-OIDP) was used to assess oral impacts, and a self-administered questionnaire was used to obtain information on demographic variables and oral behaviours. Data were analysed according to the developed algorithms. Setting., A cross-sectional survey in Suphanburi Province, Thailand. Participants., All 1126 children aged 11,12 years in a town. Main results., The sociodental approach was acceptable and not costly. In all, 54·4% had normative need under the dental needs model for life-threatening and progressive conditions, but only 16·6% had high propensity-related need; the remaining 37·8% would require dental health education or oral health promotion (DHE/OHP) or both and appropriately adjusted clinical interventions. Under the basic model of dental needs, 45·1% had normative need. Two-thirds of them (30·9%) had impact-related need and the remaining 14·2% did not have oral impacts and therefore should only receive dental health education. Only one-third of those with impact-related need had high propensity and were suitable for evidence-based conventional treatments; the remaining two-thirds should receive DHE/OHP and alternative clinical interventions. Conclusions., A sociodental system of dental needs assessment was developed and tested on school children. It decreased the estimates of conventionally assessed dental treatment needs and introduced a broader approach to care. [source] Staff Morale in Day Care Centres for Adults with Intellectual DisabilitiesJOURNAL OF APPLIED RESEARCH IN INTELLECTUAL DISABILITIES, Issue 3 2007Katerina Mascha Background, Levels of burnout, job satisfaction and intended turnover of staff working in day care centres for adults with intellectual disabilities are investigated in relation to role clarity, staff support and supervision, and coping strategies used by staff. Materials and methods, Thirty six direct-care staff of four day care centres in the UK were administered the Maslach Burnout Inventory, The Staff Support Questionnaire (SSQ), and The Shortened Ways of Coping (Revised) Questionnaire (SWC-R). Results, Although staff reported high levels of job satisfaction, they experienced moderate degrees of emotional exhaustion and personal accomplishment and reported a high propensity to leave the service. Factors identified as relating to staff morale were staff support and supervision, role clarity, wishful thinking, staff cooperation, and other practical issues regarding the day-to-day running of the service. Conclusions, Staff in day care services for people with intellectual disabilities experience similar stressors to those experienced by staff in residential facilities with the informal culture of the service being of most importance to staff morale. Suggestions for the enhancement of staff morale are provided. [source] RECONSIDERING THE INVESTMENT,PROFIT NEXUS IN FINANCE-LED ECONOMIES: AN ARDL-BASED APPROACHMETROECONOMICA, Issue 3 2008Till Van TreeckArticle first published online: 28 APR 200 ABSTRACT A Post-Keynesian growth model is developed, in which financial variables are explicitly taken into account. Variants of an investment function are estimated econometrically, applying the ARDL (auto-regressive distributed lag)-based approach proposed by Pesaran et al. (Journal of Applied Econometrics, 16 (3), pp. 289,326). The econometric results are discussed with respect to a remarkable phenomenon that can be observed for some important OECD countries since the early 1980s: accumulation has generally been declining while profit shares and rates have shown a tendency to rise. We concentrate on one potential explanation of this phenomenon, which is particularly relevant for the USA and relies on a high propensity to consume out of capital income. [source] Aspiration during swallowing in typically developing children of the first nations and inuit in CanadaPEDIATRIC PULMONOLOGY, Issue 10 2006Gina R. Rempel MD Abstract Children of the First Nations and Inuit in Canada have a high propensity for lower respiratory tract infections. Overcrowding, poor housing, passive smoke exposure, and lack of breast feeding (Martens P, Bond R, Jebamani L, Burchill C, et al. http://www.umanitoba.ca/centres/mchp/reports/pdfs/rfn_pdfs/rfn_report.pdf.; MacMillan H, Walsh C, Jamieson E, Crawford A, Boyle M. http://www.hcsc.gc.ca/fnihbdgspni/fnihb/aboriginalhealth/reports_summaries/regional_survey_ch1.pdf.; Wardman AE, Khan NA. Int J Circumpolar Health 2004;63:81,92) have been cited as important contributing factors in the occurrence of lower respiratory tract infections. However, aspiration during swallowing has thus far not been considered as a co-factor in the occurrence of lower respiratory tract infections in these children. We present a retrospective case series of seven typically developing children of the Canadian First Nations and Inuit, in whom aspiration during swallowing was detected in the course of investigating associations with recurrent lower respiratory tract infections. None of the children had any of the known risk factors for aspiration during swallowing such as developmental variation, prematurity, neuromotor problems, or anatomic abnormalities of the upper aerodigestive tract. We speculate that aspiration during swallowing in typically developing children may be an important, previously unrecognized co-factor in the occurrence of lower respiratory tract infections, particularly in the communities of the Canadian First Nations and Inuit. Further prospective studies will be needed to determine whether aspiration during swallowing represents an independent risk factor for the occurrence of lower respiratory tract infections in these children. Pediatr Pulmonol. 2006, 41:912,915. © 2006 Wiley-Liss, Inc. [source] Random discontinuous carbon fiber preforms: Experimental permeability characterization and local modelingPOLYMER COMPOSITES, Issue 4 2010A. Endruweit Injection experiments indicate that for random discontinuous carbon fiber preforms, increasingly uneven flow fronts develop with increasing fiber bundle length and filament count. While at high propensity for fiber bundle splitting, the preform permeability increases continuously with increasing fiber length, no trend can be identified at low propensity. No clear influence of the virgin bundle filament count on the preform permeability was observed. Types of sizing used on the fibers and bundle cross-sectional shapes may vary and affect the intrinsic filamentization behavior, thus dominating the preform permeability. In a model for local preform permeability, interbundle voids, distributed randomly across the preform thickness, are approximated via a regular void structure. Simulated filling patterns are qualitatively similar to those observed experimentally, showing more pronounced features than those derived from a model based on local through-thickness homogenization of the filament distribution. A model based on an alternating arrangement of fiber bundles and voids allows prediction of global preform permeability values from series of injection simulations, showing quantitatively better agreement with corresponding experimental results than the homogenization model. For global permeability, agreement between simulated and experimental mean values improves with increasing fiber volume fraction, whereas calculated coefficients of variation show no strong dependence on the fiber volume fraction. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers [source] Effect of the N1 residue on the stability of the ,-helix for all 20 amino acidsPROTEIN SCIENCE, Issue 3 2001Duncan A.E. Cochran Abstract N1 is the first residue in an ,-helix. We have measured the contribution of all 20 amino acids to the stability of a small helical peptide CH3CO-XAAAAQAAAAQAAGY-NH2 at the N1 position. By substituting every residue into the N1 position, we were able to investigate the stabilizing role of each amino acid in an isolated context. The helix content of each of the 20 peptides was measured by circular dichroism (CD) spectroscopy. The data were analyzed by our modified Lifson-Roig helix-coil theory, which includes the n1 parameter, to find free energies for placing a residue into the N1 position. The rank order for free energies is Asp,, Ala > Glu, > Glu0 > Trp, Leu, Ser > Asp0, Thr, Gln, Met, Ile > Val, Pro > Lys+, Arg, His0 > Cys, Gly > Phe > Asn, Tyr, His+. N1 preferences are clearly distinct from preferences for the preceding N-cap and ,-helix interior. pKa values were measured for Asp, Glu, and His, and protonation-free energies were calculated for Asp and Glu. The dissociation of the Asp proton is less favorable than that of Glu, and this reflects its involvement in a stronger stabilizing interaction at the N terminus. Proline is not energetically favored at the ,-helix N terminus despite having a high propensity for this position in crystal structures. The data presented are of value both in rationalizing mutations at N1 ,-helix sites in proteins and in predicting the helix contents of peptides. [source] Criminal Behavior in Antisocial Substance Abusers between Five and Fifteen Years Follow-UpTHE AMERICAN JOURNAL ON ADDICTIONS, Issue 1 2007Mats Fridell PhD Antisocial personality disorder (ASPD) is one of the most common co-occurring disorders in substance abusers, characterized among other things by a high propensity for criminal actions. A cohort of 125 substance abusers were followed in a longitudinal design. Patients were diagnosed with ASPD at an index treatment episode, interviewed at five-year follow-up, and followed-up through the Swedish criminal justice register by 2005 for the years 1995,2003. ASPD and non-ASPD subjects were compared using Mann Whitney U test for ordinal variables (number of offenses and months in prison) and chi-square tests for categorical variables. A total of 107 were alive by 1995, when the period of observation began. ASPD diagnosed at baseline was related to criminal offenses and incarceration during the follow-up from 5 to 15 years. For most categories, ASPD diagnosis was associated with higher frequency of offense. An ASPD diagnosis based on SCID-II interview made at five-year follow-up was related to the number of offenses but unrelated to incarceration. In a sample of drug abusers, ASPD was associated with high levels of criminal behavior, even years after the diagnosis was given. A diagnosis based on clinical observation during treatment was at least as predictive of criminal behavior as a diagnosis based on a SCID-II interview. [source] Fetal Anatomy of the Human Carotid Sheath and Structures In and Around ItTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 3 2010Naritomo Miyake Abstract The aim of this study was to find basic rules governing the morphological development of the typical neurovascular sheath. We carried out histological examination of 15 paraffin-embedded mid-term fetuses at 9,25 weeks of gestation (three fetuses each at 9, 12, 15, 20, and 25 weeks). As the result, the vagus nerve showed a high propensity to change its topographical relationship with the common carotid artery (CCA) during 9,20 weeks of gestation: that is, from a primitive ventral course to a final dorsal course. The adventitia of the great arteries, which was distinct from other fascial structures, became evident by 15 weeks. The carotid sheath appeared at and after 20 weeks: it was clearly separated from the prevertebral lamina of the deep cervical fasciae, but fused with the pretracheal lamina covering the strap muscles. Thus the carotid sheath, as well as the topographical relationships of structures within it, seems to become established much later than the prevertebral and pretracheal laminae of the deep cervical fasciae. However, the adventitia of the cervical great arteries consistently becomes evident much earlier than the sheath, and it seems to be regarded as one of the basic components of the fetal deep cervical fasciae. Anat Rec, 293:438,445, 2010. © 2010 Wiley-Liss, Inc. [source] Disability Support Pension Recipients: Who Gets Off (and Stays Off) Payments?THE AUSTRALIAN ECONOMIC REVIEW, Issue 1 2007Lixin Cai We use Centrelink payment records on Disability Support Pension (DSP) recipients over the period 1995 to 2002 to investigate individual transitions off payments. Our findings are consistent with the existence of a close correspondence between disability benefit receipt and labour market outcomes: entry to DSP via unemployment benefits is associated with substantially reduced prospects of exiting DSP, while employment during the DSP spell is associated with not only an increased probability of exiting DSP, but also more success in staying off payments once an exit has been made. A further finding of our analysis is that persons who exit DSP due to take-up of employment have a relatively high rate of return to payments compared with persons who exit for other reasons, and indeed exhibit a high propensity to cycle off and on payments. [source] Organic coated solids in athabasca bitumen: Characterization and process implicationsTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 4 2000Farid Bensebaa Abstract Bitumen, separated from oil sands by the hot water extraction process, contains ultra-fine (< 200 nm), inorganic solids (BS). Surfaces of BS particles are coated with toluene insoluble organic matter (TIOM). This organic material is polar and aromatic with contributions from both humic and asphaltene-like components. Although the surfaces of BS particles are dominated by TIOM, the coverage is patchy rather than continuous. As a result, these solids are capable of stabilizing fine water emulsions in the bitumen phase. The nature of the organic matter on the surfaces of the particles is such that it has a high propensity to form coke. Therefore, these particles can also play a role in fouling on equipment and catalysts. Le bitume séparé des sables pétrolifères par le procédé d'extraction à air chaud, contient des solides inorganiques (BS) ultrafins (<200 mm). Les surfaces des particules BS sont recouvertes de matière organique insoluble au toluène (TIOM). Cette matière organique est polaire et aromatique avec des contributions provenant de composants humiques et proches de l'asphaltène. Bien que les surfaces des particules BS soient dominées par le TIOM, le revêtement est irrégulier plutôt que continu. Par conséquent, ces solides sont capables de stabiliser des émulsions aqueuses fines dans la phase du bitume. La nature de la matière organique sur les surfaces des particules est telle qu'elle a une forte propension à former du coke. Ces particules peuvent donc jouer un rôle dans l'encrassement des équipements et des catalyseurs. [source] Variation in neighbouring genes of the dopaminergic and serotonergic systems affects feather pecking behaviour of laying hensANIMAL GENETICS, Issue 2 2009K. Flisikowski Summary Feather pecking is a behavioural disorder of laying hens and has serious animal welfare and economic implications. One of the several aetiological hypotheses proposes that the disorder results from redirected exploratory behaviour. Variation in the gene encoding the dopamine D4 receptor (DRD4) has been shown to be associated with exploratory behaviour in several species, including in a passerine bird species. We therefore considered DRD4 as a candidate gene for feather pecking. We have annotated DRD4 in the chicken genome and have re-sequenced it in 140 animals belonging to: experimental layer lines divergently selected for high and low propensity to feather pecking; the unselected founder population; and two commercial lines with low and high propensity to feather pecking. We have identified two sub-haplotypes of DRD4 that are highly significantly associated with feather pecking behaviour in the experimental (P = 7.30 × 10,7) as well as in the commercial lines (P = 2.78 × 10,6). Linkage disequilibrium (LD) extends into a neighbouring gene encoding deformed epidermal autoregulatory factor 1 (DEAF1). The product of DEAF1 regulates the transcription of the gene encoding the serotonin (5-hydroxytryptamine) 1A receptor. Thus, DEAF1 represents another candidate gene for feather pecking. Re-sequencing of five animals homozygous for the ,low-pecking' sub-haplotype and of six animals homozygous for the ,high-pecking' sub-haplotype delineated an LD block of 14 833 bases spanning the two genes. None of the variants in the LD block is obviously functional. However, the haplotype information will be useful to select against the propensity to feather pecking in chicken and to elucidate the functional implications of the variants. [source] Subgroup Hypotheses: Clinician's Friend or Researcher's Fiction?ACADEMIC EMERGENCY MEDICINE, Issue 8 2009Peter C. Wyer MD Abstract Researchers and clinicians may be tempted to consider apparent differences in effects of interventions in subgroups of study populations for the purposes of individualizing care or directing subsequent focused research efforts. Such "subgroup hypotheses" have a high propensity of being artifacts of chance and are rarely supported when stringent criteria are applied. Subgroup hypotheses emerging from single trials should rarely if ever be considered for application. This article describes published criteria for evaluating the believability of a subgroup hypothesis and presents a conceptual framework for understanding the principles underlying those criteria. Examples of both failed and validated subgroup hypotheses drawn from emergency medicine research are given. [source] The hepatitis C virus enigmaAPMIS, Issue 5-6 2009HELGE MYRMEL Hepatitis C virus (HCV) has a high propensity to establish chronic infection with end-stage liver disease. The high turnover of virus particles and high transcription error rates due to lack of proof-reading function of the viral polymerase imply that HCV exists as quasispecies, thus enabling the virus to evade the host immune response. Clearance of the virus is characterized by a multispecific, vigorous and persistent T-cell response, whereas T-cell responses are weak, narrow and transient in patients who develop chronic infection. At present, standard treatment is a combination of pegylated interferon-, and ribavirin, with a sustained viral response rate of 40,80%, depending on genotype. The mechanisms for the observed synergistic effects of the two drugs are still not known in detail, but in addition to direct antiviral mechanisms, the immunomodulatory effects of both drugs seem to be important, with a shift from Th2- to Th1-cytokine profiles in successfully treated patients. This article describes virus,host relations in the natural course of HCV infection and during treatment. [source] The naturalization to invasion transition: Are there introduction-history correlates of invasiveness in exotic plants of Australia?AUSTRAL ECOLOGY, Issue 6 2010MEGAN L. PHILLIPS Abstract Of the large number of exotic plant species that become naturalized in new geographic regions, only a subset make the transition to become invasive. Identifying the factors that underpin the transition from naturalization to invasion is important for our understanding of biological invasions. To determine introduction-history correlates of invasiveness among naturalized plant species of Australia, we compared geographic origin, reason for introduction, minimum residence time and growth form between naturalized non-invasive species and naturalized invasive plant species. We found that more invasive species than expected originated from South America and North America, while fewer invasive species than expected originated from Europe and Australasia. There was no significant difference between invasive and non-invasive species with respect to reason for introduction to Australia. However, invasive species were significantly more likely to have been resident in Australia for a longer period of time than non-invasive species. Residence times of invasive species were consistently and significantly higher than residence times of non-invasive species even when each continent of origin was considered separately. Furthermore, residence times for both invasive and non-invasive species varied significantly as a function of continent of origin, with species from South America having been introduced to Australia more recently on average than species from Europe, Australasia and North America. We also found that fewer invasive species than expected were herbs and more invasive species than expected were primarily climbers. Considered together, our results indicate a high propensity for invasiveness in Australia among exotic plant species from South America, given that they appear in general capable of more rapid shifts to invasiveness than aliens from other regions. Furthermore, our findings support an emerging global generality that introduction-history traits must be statistically controlled for in comparative studies exploring life-history and ecological correlates of invasion success. [source] Osteosarcoma of the pelvis in children and young adults: The St. Jude Children's Research Hospital experience,CANCER, Issue 7 2005Raya Saab M.D. Abstract BACKGROUND Pelvic osteosarcomas are difficult to resect. The authors reviewed their institution's experience with patients who had such tumors to characterize the patients' clinical findings and to assess the impact of surgical resection on outcome. METHODS A review was conducted of the records from patients with pelvic osteosarcoma who were treated at the authors' institution between January, 1970 and March, 2004. RESULTS Among 442 patients with osteosarcoma, 19 patients (4%) had high-grade tumors arising in the pelvic bones, including the ilium in 15 patients, the pubis in 2 patients, and the sacrum in 2 patients. The median patient age at diagnosis was 16.8 years. Four tumors were secondary to radiation therapy. Five patients had metastases in the lung (n = 4 patients) or bone (n = 1 patient) at diagnosis. Ten tumors were chondroblastic. The median greatest tumor dimension for the 13 tumors with known size was 10 cm. Ten patients had unresectable pelvic tumors, and 9 patients underwent hemipelvectomy (2 internal and 7 external); complete resection with negative margins was achieved in 5 patients. Four patients survived, including one patient who survived with disease. Of the three patients who survived disease-free, one patient underwent complete resection, one patient underwent incomplete resection (nonviable tumor at the soft tissue margin) with a good response to chemotherapy, and one patient with a sacral tumor underwent radiotherapy only for local control. Of the 9 patients who underwent resection, 7 experienced disease recurrence (n = 5 patients) or progression (n = 2 patients) at distant sites and died. All patients with metastatic disease at diagnosis died. CONCLUSIONS Pelvic osteosarcomas often were large and unresectable. A high propensity for metastasis contributed to the poor outcome of patients with pelvic osteosarcoma. New therapeutic approaches are needed. Cancer 2005. © 2005 American Cancer Society. [source] Molecular basis of opioid dependence: role of signal regulation by G-proteinsCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 5-6 2003Prudence H Tso Summary 1.,Morphine and opiate narcotics are potent analgesics that have a high propensity to induce tolerance and physical dependence following their repeated administration. 2.,The molecular basis of opiate dependence has not been completely elucidated, although the participation of opioid receptors is a prerequisite. Cellular dependence on opioids is believed to result from the chronic stimulation of opioid-regulated signalling networks. 3.,As G-protein-coupled receptors, the opioid receptors must rely on heterotrimeric G-proteins for signal transduction. Recent advances in our understanding of G-protein signalling have unveiled novel signalling molecules and mechanisms, some of which may be intricately involved in the manifestation of opiate dependence. 4.,In the present review, we will attempt to trace chronic opioid signals along elaborate G-protein-regulated pathways. [source] | |||||||||||||||||||