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1.
Sci Rep ; 11(1): 12824, 2021 06 17.
Artículo en Inglés | MEDLINE | ID: mdl-34140573

RESUMEN

Dinophyte evolution is essentially inferred from the pattern of thecal plates, and two different labelling systems are used for the important subgroups Gonyaulacales and Peridiniales. The partiform hypotheca of cladopyxidoid dinophytes fits into the morphological concepts of neither group, although they are assigned to the Gonyaulacales. Here, we describe the thecate dinophyte Fensomea setacea, gen. & sp. nov., which has a cladopyxidoid tabulation. The cells displayed a Kofoidean plate formula APC, 3', 4a, 7″, 7C, 6S, 6''', 2'''', and slender processes were randomly distributed over the echinate or baculate surface. In addition, we obtained rRNA sequences of F. setacea, gen. & sp. nov., but dinophytes that exhibit a partiform hypotheca did not show a close relationship to Gonyaulacales. Character evolution of thecate dinophytes may have progressed from the ancestral state of six postcingular plates, and two more or less symmetrically arranged antapical plates, towards patterns of only five postcingular plates (Peridiniales) or more asymmetrical configurations (Gonyaulacales). Based on our phylogenetic reconsiderations the contact between the posterior sulcal plate and the first postcingular plate, as well as the contact between an antapical plate and the distalmost postcingular plate, do not represent a rare, specialized gonyaulacoid plate configuration (i.e., the partiform hypotheca of cladopyxidoid dinophytes). Instead, these contacts correspond to the common and regular configuration of peridinioid (and other) dinophytes.


Asunto(s)
Dinoflagelados/citología , Dinoflagelados/genética , Dinoflagelados/clasificación , Dinoflagelados/ultraestructura , Funciones de Verosimilitud , Filogenia
2.
Support Care Cancer ; 29(6): 3129-3135, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33067766

RESUMEN

Oncological studies have shown that patients consider small benefits sufficient to make adjuvant chemotherapy worthwhile. We sought to determine the minimal survival benefits that patients considered enough to legitimate allogeneic haematopoietic stem cell transplantation (HCT) and the factors associated with patient preferences. One hundred eighty-four patients having previously received allogeneic HCT at our centre were included and completed a questionnaire exploring patient expectations elicited by time trade-off scenarios as well as quality of life (QoL), symptoms of graft-versus host disease (GvHD) and sociodemographic characteristics. The majority of patients considered a minimal survival benefit of at least 5 (38.6%) or 10 years (41.9%) sufficient to justify HCT, with less than 5% considering survival < 1 year sufficient to warrant HCT. In terms of minimal cure rate, a cumulative 14.8% of patients accepted cure rates below 30% and 30.6% rates below 50%. Likelihood-ratio tests were significant for the effect of age at transplant on expected minimal survival (p = 0.007) and cure rates (p = 0.0001); that is, younger patients at HCT were more likely to accept smaller survival and cure rates. Pre-transplant risk score, QoL, GvHD score and sociological factors did not seem to influence patients' expectations. In conclusion, patient expectations of treatment were much higher than what had been reported in oncological studies. Patients who experienced HCT considered a survival superior to 1 year and cure rates above 50% sufficient to make it worthwhile. Younger patients were more likely to accept smaller benefits; no other predictors for preferences could be detected.


Asunto(s)
Toma de Decisiones/fisiología , Trasplante de Células Madre Hematopoyéticas/métodos , Prioridad del Paciente/psicología , Calidad de Vida/psicología , Acondicionamiento Pretrasplante/métodos , Trasplante Homólogo/métodos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
3.
Nurs Crit Care ; 25(1): 8-15, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31397952

RESUMEN

BACKGROUND: Non-communicative adult ICU patients are vulnerable to inadequate pain management with potentially severe consequences. In German-speaking countries, there is limited availability of a validated pain assessment tool for this population. AIM: The aim of this observational study was to test the German version of the Critical-Care Pain Observation Tool (CPOT) in a heterogeneous adult ICU population. METHODS: The CPOT's feasibility for clinical use was evaluated via a questionnaire. For validity and reliability testing, the CPOT was compared with the Behavioural Pain Scale (BPS) and patient's self-report in 60 patients during 480 observations simultaneously performed by two raters. RESULTS: The feasibility evaluation demonstrated high satisfaction with clinical usability (85% of responses 4 or 5 on a 5-point Likert scale). The CPOT revealed excellent criterion validity [agreement between CPOT and BPS 94.0%, correlation of CPOT and BPS sum scores r = 0.91 (P < .05), agreement of CPOT with patient self-report 81.4%], good discriminant validity [mean difference of CPOT scores between at rest and non-painful stimulus 0.33 (P < .029), mean difference of CPOT scores between at rest, and painful stimulus 2.19 (P < .001)], for a CPOT cut-off score of >2 a high sensitivity and specificity (93% and 84%), high positive predictive value (85%), and a high negative predictive value (93%). The CPOT showed acceptable internal consistency (Cronbach's α 0.79) and high inter-rater reliability [90% agreement, no differences in CPOT sum scores in 64.2% of observations, and correlation for CPOT sum scores r = 0.72 (P < .05)]. Self-report obtained in patients with delirium did not correlate with the CPOT rating in 62% of patients. CONCLUSION: This is the first validation study of the CPOT evaluating all of the described validity dimensions, including feasibility, at once. The results are congruent with previous validations of the CPOT with homogeneous samples and show that it is possible to validate a tool with a heterogeneous sample. Further research should be done to improve pain assessment and treatment in ICU patients with delirium. RELEVANCE TO CLINICAL PRACTICE: The German CPOT version can be recommended for ICUs in German-speaking countries.


Asunto(s)
Enfermería de Cuidados Críticos , Enfermedad Crítica , Unidades de Cuidados Intensivos , Dimensión del Dolor/estadística & datos numéricos , Respiración Artificial , Anciano , Femenino , Alemania , Humanos , Masculino , Dimensión del Dolor/enfermería , Reproducibilidad de los Resultados , Respiración Artificial/enfermería , Autoinforme , Encuestas y Cuestionarios , Suiza
4.
Transplant Rev (Orlando) ; 33(1): 17-28, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30472153

RESUMEN

BACKGROUND: Reviews on alcohol use in transplant recipients focus on liver recipients and their risk of post-transplant rejection, but do not assess alcohol use in kidney, heart, or lung transplant recipients. This systematic review and meta-analysis aims to synthesize the evidence on correlates and outcomes of any alcohol use and at-risk drinking after solid organ transplantation (Tx). METHODS: We searched 4 databases for quantitative studies in adult heart, liver, kidney and lung Tx recipients, investigating associations between post-Tx alcohol use and correlates and/or clinical, economic or quality of life outcomes. Paper selection, data extraction and quality assessment were performed by 2 reviewers independently. A pooled odds ratio (OR) was computed for each correlate/outcome reported ≥5 times. RESULTS: Of the 5331 studies identified, 76 were included in this systematic review (93.3% on liver Tx; mean sample size 148.9 (SD = 160.2); 71.9% male; mean age 48.9 years (SD = 6.5); mean time post-Tx 57.7 months (SD = 23.1)). On average, 23.6% of patients studied used alcohol post-transplant. Ninety-three correlates of any post-Tx alcohol use were identified, and 9 of the 19 pooled ORs were significantly associated with a higher odds for any post-Tx alcohol use: male gender, being employed post-transplant, smoking pre-transplant, smoking post-transplant, a history of illicit drug use, having first-degree relatives who have alcohol-related problems, sobriety <6 months prior to transplant, a history of psychiatric illness, and having received treatment for alcohol-related problems pre-transplant. On average 15.1% of patients had at-risk drinking. A pooled OR was calculated for 6 of the 47 correlates of post-Tx at risk drinking investigated, of which pre-transplant smoking was the only correlate being significantly associated with this behavior. None of the outcomes investigated were significantly associated with any use or at-risk drinking. CONCLUSION: Correlates of alcohol use remain under-investigated in solid organ transplant recipients other than liver transplantation. Further research is needed to determine whether any alcohol use or at-risk drinking is associated with poorer post-transplant outcomes. Our meta-analysis highlights avenues for future research of higher methodological quality and improved clinical care. PROTOCOL REGISTRATION: PROSPERO protocol CRD42015003333.


Asunto(s)
Consumo de Bebidas Alcohólicas , Trasplante de Órganos , Receptores de Trasplantes/psicología , Humanos , Calidad de Vida
5.
Eur J Cardiovasc Nurs ; 17(4): 356-367, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29231747

RESUMEN

BACKGROUND: As medication non-adherence is a major risk factor for poor post-transplant outcomes, we explored how adherence is assessed, enhanced and integrated across the transplant continuum. AIM: The aim of this study was to study practice patterns regarding pre- and post-transplant medication adherence assessment and interventions in international heart transplant centres. METHODS: We used data from the Building Research Initiative Group: chronic illness management and adherence in heart transplantation (BRIGHT) study, a cross-sectional study conducted in 36 heart transplant centres in 11 countries. On a 27-item questionnaire, 100 clinicians (range one to five per centre) reported their practice patterns regarding adherence assessment and intervention strategies pre-transplant, immediately post-transplant, less than one year, and one or more year post-transplant. Educational/cognitive, counselling/behavioural and psychosocial/affective strategies were assessed. Clinicians' responses (intervention present vs. absent; or incongruence in reporting intervention) were aggregated at the centre level. RESULTS: The adherence assessment method most commonly used along the transplant continuum was questioning patients (range 75-88.9%). Pre-transplant, all three categories of intervention strategy were applied. Providing reading materials (82.9%) or instructions (68.6%), involving family or support persons in education (91.4%), and establishing partnership (91.4%) were used most frequently. Post-transplant, strategies closely resembled those employed pre-transplant. Training patients (during recovery) and cueing were more often applied during hospitalisation (74.3%). After the first year post-transplant, except for motivational interviewing (25.7-28.6%), the number of strategies decreased. CONCLUSIONS: Across the transplant continuum, diverse adherence interventions are implemented; however, post-transplant, the frequency of adherence interventions decreases. Therefore, increased investment is necessary in long-term adherence interventions.

6.
Support Care Cancer ; 26(3): 833-841, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28918604

RESUMEN

PURPOSE: High-dose melphalan and autologous stem cell transplantation (ASCT) are associated with high symptom burden. This study aimed to explore multiple myeloma (MM) patients' experience of symptom frequency, intensity, and distress during therapy. METHODS: This descriptive longitudinal study enrolled 29 MM patients who completed the 43-item PROVIVO questionnaire, measuring symptom experience across the dimensions of frequency, intensity, and distress at four assessment points: hospital admission (T0), leucocyte nadir (T1), discharge (T2), and 30 days post discharge (T3). Symptom assessment covered five categories: (1) physical, (2) emotional, (3) cognitive, (4) male/female urogenital symptoms, and (5) follow-up care planning (e.g., financial problems). Results were displayed as heat maps and bubble graphs for each patient, differences between T0 and T4 individually assessed, and intensity (IMS) and mean distress scores (DMS) calculated on a scale from 0 to 4. RESULTS: The most frequent, intense, and distressing physical symptoms were fatigue, diarrhea, and decreased appetite. As expected, peak symptom intensity (decreased appetite 2.79) and distress (diarrhea 2.11) were reported during high-dose melphalan and the leucocyte nadir (T1). Thereafter, most symptoms' intensity and distress improved. Items on urogenital symptoms remained predominantly unanswered or patients were sexually inactive. CONCLUSIONS: PROVIVO enabled exploration of various dimensions of MM patients' symptom experiences, which differed substantially before and after ASCT. Our results suggest that high-dose melphalan, ASCT, and other intensive novel agent therapies warrant targeted symptom management programs that include focused patient support.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/métodos , Melfalán/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , Trasplante Autólogo/métodos , Adulto , Anciano , Femenino , Humanos , Estudios Longitudinales , Masculino , Melfalán/administración & dosificación , Melfalán/farmacología , Persona de Mediana Edad , Mieloma Múltiple/patología
7.
Eur J Oncol Nurs ; 27: 17-27, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28279392

RESUMEN

PURPOSE: To give a first description of the perception of late effects among long-term survivors after Allogeneic Haematopoietic Stem Cell Transplantation (HSCT) and to validate the German Brief Illness Perception Questionnaire (BIPQ). METHODS: This is a secondary analysis of data from the cross-sectional, mixed-method PROVIVO study, which included 376 survivors from two Swiss HSCT-centres. First, we analysed the sample characteristics and the distribution for each BIPQ item. Secondly, we tested three validity types following the American Educational Research Association (AERA)Standards: content validity indices (CVIs) were assessed based on an expert survey (n = 9). A confirmatory factor analysis (CFA) explored the internal structure, and correlations tested the validity in relations to other variables including data from the Hospital Anxiety and Depression Scale (HADS), the number and burden of late effects and clinical variables. RESULTS: In total, 319 HSCT recipients returned completed BIPQs. For this sample, the most feared threat for post-transplant life was long lasting late effects (median = 8/10). The expert-survey revealed an overall acceptable CVI (0.82), three items-on personal control, treatment control and causal representation-yielded low CVIs (<.78). The CFA confirmed that the BIPQ fits the underlying construct, the Common-Sense Model (CSM) (χ2 (df) = 956.321, p = 0.00). The HADS-scores correlated strongly with the item emotional representation (r = 0.648; r = 0.656). CONCLUSION: According to its overall content validity, the German BIPQ is a promising instrument to gain deeper insights into patients' perceptions of HSCT late effects. However, as three items revealed potential problems, improvements and adaptions in translation are therefore required. Following these revisions, validity evidence should be re-examined through an in-depth patient survey.


Asunto(s)
Emociones , Trasplante de Células Madre Hematopoyéticas/psicología , Percepción , Sobrevivientes/psicología , Adulto , Anciano , Aloinjertos , Estudios Transversales , Análisis Factorial , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Suiza , Traducciones , Adulto Joven
8.
Transplantation ; 100(11): 2252-2263, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27479162

RESUMEN

BACKGROUND: Despite smoking being an absolute or relative contraindication for transplantation, about 11% to 40% of all patients continue or resume smoking posttransplant. This systematic review with meta-analysis investigated the correlates and outcomes associated with smoking after solid organ transplantation. METHODS: We searched PubMed, EMBASE, CINAHL, and PsycINFO from inception until January 2016, using state-of-the art methodology. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were computed for correlates/outcomes investigated 5 times or more. RESULTS: Seventy-three studies (43 in kidney, 17 in heart, 12 in liver, 1 in lung transplantation) investigated 95 correlates and 24 outcomes, of which 6 correlates and 4 outcomes could be included in the meta-analysis. The odds of smoking posttransplant were 1.33 times higher in men (95% CI, 1.12-1.57). Older individuals were significantly less likely to smoke (OR, 0.48; 95% CI, 0.38-0.62), as were patients with a higher body mass index (OR, 0.68; 95% CI, 0.52-0.89). Hypertension (OR, 1.16; 95% CI, 0.77-1.75), diabetes mellitus (OR, 0.52; 95% CI, 0.15-1.78), and having a history of cardiovascular disease (OR, 0.92; 95% CI, 0.77-1.09) were not significant correlates. Posttransplant smokers had higher odds of newly developed posttransplant cardiovascular disease (OR, 1.41; 95% CI, 1.02-1.95), nonskin malignancies (OR, 2.58; 95% CI, 1.26-5.29), a shorter patient survival time (OR, 0.59; 95% CI, 0.44-0.79), and higher odds of mortality (OR, 1.74; 95% CI, 1.21-2.48). CONCLUSIONS: Posttransplant smoking is associated with poor outcomes. Our results might help clinicians to understand which patients are more likely to smoke posttransplant, guide interventional approaches, and provide recommendations for future research.


Asunto(s)
Trasplante de Órganos/efectos adversos , Fumar/efectos adversos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Enfermedades Cardiovasculares/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
9.
Eur J Oncol Nurs ; 19(1): 66-74, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25190633

RESUMEN

PURPOSE: The aim of this sequential mixed methods study was to develop a PRO-CTCAE (Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events)-based measure of the symptom experience of late effects in German speaking long-term survivors of allogeneic stem cell transplantation (SCT), and to examine its content validity. METHODS: The US National Cancer Institute's PRO-CTAE item library was translated into German and linguistically validated. PRO-CTCAE symptoms prevalent in ≥50% of survivors (n = 15) and recognized in its importance by SCT experts (n = 9) were identified. Additional concepts relevant to the symptom experience and its consequences were elicited. Content validity of the PROVIVO (Patient-Reported Outcomes of long-term survivors after allogeneic SCT) instrument was assessed through an additional round of cognitive debriefing in 15 patients, and item and scale content validity indices by 9 experts. RESULTS: PROVIVO is comprised of a total of 49 items capturing the experience of physical, emotional and cognitive symptoms. To improve the instrument's utility for clinical decision-making, questions soliciting limitations in activities of daily living, frequent infections, and overall well-being were added. Cognitive debriefings demonstrated that items were well understood and relevant to the SCT survivor experience. Scale Content Validity Index (CVI) (0.94) and item CVI (median = 1; range 0.75-1) were very high. CONCLUSIONS: Qualitative and quantitative data provide preliminary evidence supporting the content validity of PROVIVO and identify a PRO-CTCAE item bundle for use in SCT survivors. A study to evaluate the measurement properties of PROVIVO and to examine its capacity to improve survivorship care planning is underway.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia/complicaciones , Lingüística , Evaluación del Resultado de la Atención al Paciente , Autoinforme , Evaluación de Síntomas , Adulto , Anciano , Femenino , Alemania , Humanos , Leucemia/diagnóstico , Leucemia/terapia , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Factores Socioeconómicos , Traducción , Adulto Joven
10.
Prog Transplant ; 23(3): 235-46, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23996943

RESUMEN

BACKGROUND: Understanding outcomes after transplant requires a biopsychosocial model that includes biomedical and psychosocial factors. The latter, to date, are assessed only in a limited way as part of transplant registries or cohort studies. The Swiss Transplant Cohort Study (STCS) is a nationwide open cohort study (starting May 2008) to systematically and prospectively assess psychosocial factors. This article describes the framework underpinning STCS's psychosocial assessment. METHODS: The STCS framework was adapted from the multidimensional conceptual perspective of Dew et al to describe transplant psychosocial domains and specific outcomes by adding a time perspective, a system perspective, and interaction among domains. RESULTS: We propose a multidimensional, multilevel biopsychosocial framework representing mutually influencing domains from before to after transplant, and exemplify each domain by factors included in STCS and their measurement. The transplant patient, centrally positioned, is described by clinical and sociodemographic characteristics (eg, socioeconomic status, educational, professional, and relationship status). The following psychosocial domains further describe the patient: (1) physical/functional (eg, perceived health status, sleep quality, daytime sleepiness), (2) psychological (eg, depression, stress), (3) behavioral (eg, medication adherence, smoking, drug use, physical activity, sun protection), (4) social (eg, work capacity/return to work), and (5) global quality of life. Factors associated with health care system level (eg, trust in transplant team) are also included in the model. CONCLUSION: The STCS's psychosocial framework provides a basis for studying the interplay of biomedical, sociodemographic, psychosocial, behavioral, and health care system factors in view of transplant outcomes and therefore has the potential to guide biopsychosocial transplant research.


Asunto(s)
Trasplante de Órganos/psicología , Apoyo Social , Encuestas y Cuestionarios , Estudios de Cohortes , Femenino , Humanos , Masculino , Evaluación de Resultado en la Atención de Salud , Satisfacción del Paciente , Escalas de Valoración Psiquiátrica , Calidad de Vida , Suiza
11.
Protist ; 164(5): 583-97, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23850812

RESUMEN

The Thoracosphaeraceae are dinophytes that produce calcareous shells during their life history, whose optical crystallography has been the basis for the division into subfamilies. To evaluate the validity of the classification (mainly applied by palaeontologists), living material of phylogenetic key species is necessary albeit frequently difficult to access for contemporary morphological and molecular analyses. We isolated and established five living strains of the rare fossil-taxon †Posoniella tricarinelloides from different sediment samples collected in the South China Sea, Yellow Sea and in the Mediterranean Sea (west coast off Italy). Here, we provide detailed descriptions of its morphology and conducted phylogenetic analyses based on hundreds of accessions and thousands of informative sites on concatenated rRNA datasets. Within the monophyletic Peridiniales, †P. tricarinelloides was reliably nested in the Thoracosphaeraceae and exhibited two distinct morphological types of coccoid cells. The two morphologies of coccoid cells would have been assigned to different taxa at the subfamily level if found separately in fossil samples. Our results thus challenge previous classification concepts within the dinophytes and underline the importance of comparative morphological and molecular studies to better understand the complex biology of unicellular organisms such as †P. tricarinelloides.


Asunto(s)
Dinoflagelados/crecimiento & desarrollo , Dinoflagelados/genética , Agua de Mar/parasitología , ADN Protozoario/genética , Dinoflagelados/clasificación , Dinoflagelados/aislamiento & purificación , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico/genética
12.
Semin Hematol ; 50 Suppl 1: S39-42, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23664515

RESUMEN

Incorporating patient-reported outcomes (PROs) when studying patients with immune thrombocytopenia (ITP) is essential since treatment decisions are complex and using platelet count only partly explains disease burden. Since most symptoms are only experienced subjectively and are seldom captured during clinician-based evaluations, using self-report is crucial for early symptom detection. However, capturing the patient's illness experience necessitates using well-developed and validated instruments. This article provides insight on the importance of using PROs in ITP, summarizes the methodological steps to develop PRO instruments, and discusses challenges related to integrating PROs into research and clinical practice.


Asunto(s)
Evaluación del Resultado de la Atención al Paciente , Autoinforme/normas , Trombocitopenia/psicología , Trombocitopenia/terapia , Humanos , Prioridad del Paciente , Satisfacción del Paciente , Calidad de Vida , Encuestas y Cuestionarios , Resultado del Tratamiento
14.
J Phycol ; 48(5): 1107-18, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27011272

RESUMEN

The diversity of extant calcareous dinophytes (Thoracosphaeraceae, Dinophyceae) is currently not sufficiently recorded. The majority of their coccoid stages are cryptotabulate or entirely atabulate, whereas relatively few forms exhibit at least some degree of tabulation more than the archeopyle. A survey of coastal surface sediment samples from the Mediterranean Sea resulted in the isolation and cultivation of several strains of calcareous dinophytes showing a prominent tabulation. We investigated the morphologies of the thecate and the coccoid cells and conducted phylogenetic analyses using Maximum Likelihood and Bayesian approaches. The coccoid cells showed a distinct reflection of the cingulum (and were thus cingulotabulate), whereas thecal morphology corresponded to the widely distributed and species-rich Scrippsiella. As inferred from molecular sequence data (including 81 new GenBank entries), the strains belonged to the Scrippsiella sensu lato clade of the Thoracosphaeraceae and represented two distinct species. Morphological details likewise indicated two distinct species with previously unknown coccoid cells that we describe here as new, namely S. bicarinata spec. nov. and S. kirschiae spec. nov. Cingulotabulation results from the fusion of processes representing the pre- and postcingular plate series in S. bicarinata, whereas the ridges represent sutures between the cingulum and the pre- and postcingular series in S. kirschiae, respectively. Bicarinate cingulotabulation appears homoplasious among calcareous dinophytes, which is further supported by a comparison to similar, but only distantly related fossil forms.

15.
Mol Phylogenet Evol ; 36(3): 444-55, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15964218

RESUMEN

The phylogenetic relationships of calcareous dinoflagellates (i.e., Calciodinellaceae and Thoracosphaera) are investigated. Molecular data from the ribosomal 5.8S rRNA and highly conserved motifs of the ITS1 show Calciodinellaceae s.l. to be monophyletic when few non-calcareous taxa are included. They segregate into three monophyletic assemblages in a molecular analysis that considers the 5.8S rRNA and both the Internal Transcribed Spacer regions ITS1 and ITS2: a clade comprising species of Ensiculifera and Pentapharsodinium (E/P-clade), Scrippsiella s.l. (including fossil-based taxa such as Calciodinellum and Calcigonellum), and a heterogeneous group (T/P-clade) of calcareous (e.g., Thoracosphaera) and non-calcareous taxa (e.g., the highly toxic Pfiesteria). The potential to produce calcareous structures is considered as apomorphic within alveolates, and non-calcareous taxa nesting with calcareous dinoflagellates may have reduced calcification secondarily. Molecular results do not contradict general evolutionary scenarios provided by previous morphological (mainly paleontological) investigations.


Asunto(s)
ADN Espaciador Ribosómico/genética , Dinoflagelados/clasificación , Dinoflagelados/genética , Filogenia , ARN Ribosómico 5.8S/genética , Animales , Secuencia de Bases , Datos de Secuencia Molecular , Alineación de Secuencia
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