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1.
Proc Natl Acad Sci U S A ; 118(52)2021 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-34930840

RESUMEN

Thymol and carvacrol are phenolic monoterpenes found in thyme, oregano, and several other species of the Lamiaceae. Long valued for their smell and taste, these substances also have antibacterial and anti-spasmolytic properties. They are also suggested to be precursors of thymohydroquinone and thymoquinone, monoterpenes with anti-inflammatory, antioxidant, and antitumor activities. Thymol and carvacrol biosynthesis has been proposed to proceed by the cyclization of geranyl diphosphate to γ-terpinene, followed by a series of oxidations via p-cymene. Here, we show that γ-terpinene is oxidized by cytochrome P450 monooxygenases (P450s) of the CYP71D subfamily to produce unstable cyclohexadienol intermediates, which are then dehydrogenated by a short-chain dehydrogenase/reductase (SDR) to the corresponding ketones. The subsequent formation of the aromatic compounds occurs via keto-enol tautomerisms. Combining these enzymes with γ-terpinene in in vitro assays or in vivo in Nicotiana benthamiana yielded thymol and carvacrol as products. In the absence of the SDRs, only p-cymene was formed by rearrangement of the cyclohexadienol intermediates. The nature of these unstable intermediates was inferred from reactions with the γ-terpinene isomer limonene and by analogy to reactions catalyzed by related enzymes. We also identified and characterized two P450s of the CYP76S and CYP736A subfamilies that catalyze the hydroxylation of thymol and carvacrol to thymohydroquinone when heterologously expressed in yeast and N. benthamiana Our findings alter previous views of thymol and carvacrol formation, identify the enzymes involved in the biosynthesis of these phenolic monoterpenes and thymohydroquinone in the Lamiaceae, and provide targets for metabolic engineering of high-value terpenes in plants.


Asunto(s)
Cimenos/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Lamiaceae/metabolismo , Deshidrogenasas-Reductasas de Cadena Corta/metabolismo , Timol/análogos & derivados , Timol/metabolismo , Cimenos/química , Sistema Enzimático del Citocromo P-450/genética , Lamiaceae/enzimología , Lamiaceae/genética , Redes y Vías Metabólicas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Deshidrogenasas-Reductasas de Cadena Corta/genética , Timol/química
2.
Cogn Behav Ther ; : 1-22, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39206950

RESUMEN

Mental contamination refers to feelings of dirtiness and/or urges to wash that arise without direct contact with a contaminant. Cognitive models propose that this results from "serious, negative misappraisals of perceived violations". However, the specific violation misappraisals most relevant to mental contamination have yet to be established empirically, in part due to the lack of a comprehensive validated inventory of violation appraisals. Therefore, this study's aim was to develop and validate such a measure. Items for the new Violation Appraisal Measure (VAM) were developed from qualitative interviews, theoretical models, and previous empirical work. An Exploratory Factor Analysis was conducted in a sample of (n = 300) undergraduate participants, which revealed a four-factor structure: Responsibility/Self-Blame, Permanence, Mistrust, and Self-Worth. The VAM showed excellent internal consistency (α = 0.90), good convergent (r = .50 to .64) and adequate divergent (r = -.01 to .46) validity and was predictive of mental contamination symptoms over and above existing related appraisal measures, ΔF(1,289) = 29.35, p < .001, ΔR2 = 0.06. A Confirmatory Factor Analysis in a second sample of (n = 300) undergraduate students confirmed strong model fit for the four-factor structure of the VAM. The development of the VAM is an important contribution to the search for empirically based cognitive mechanisms in mental contamination and other violation-related sequelae.

3.
Behav Cogn Psychother ; 52(5): 463-477, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38679952

RESUMEN

BACKGROUND: Cognitive models of mental contamination (i.e. feelings of internal dirtiness without contact with a contaminant) propose that these feelings arise when individuals misappraise a violation. However, an operational definition of 'violation' and identification of specific violation misappraisals is limited. AIMS: This study's aim was to elaborate on cognitive models using qualitative data from those with lived experience to fill these gaps. METHOD: Twenty participants with a diagnosis of obsessive-compulsive disorder and/or a trauma history took part in a semi-structured interview about violation. Grounded theory was used to analyse interview transcripts. DISCUSSION: Three categories emerged, each with several themes - qualities of violation, violation-related appraisals, and violation-related behaviours. Different violation-related appraisals were associated with different emotions and urges. Specific self-focused appraisal sub-themes (i.e. permanence of consequences; self-worth; responsibility, self-blame and regret) were most closely related to emotions tied to mental contamination. These findings support and expand upon existing cognitive models of mental contamination, identifying key violation-related appraisals and differentiating between mental contamination-related appraisals and those related to other emotional sequelae. Future quantitative and experimental research can evaluate the potential of these appraisals as intervention targets.


Asunto(s)
Emociones , Trastorno Obsesivo Compulsivo , Investigación Cualitativa , Humanos , Trastorno Obsesivo Compulsivo/psicología , Femenino , Masculino , Adulto , Persona de Mediana Edad , Autoimagen , Teoría Fundamentada
4.
Liver Transpl ; 28(8): 1299-1305, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35229446

RESUMEN

Anonymous living organ donation has recently become more common in select transplantation programs, with donors voluntarily offering a kidney or a lobe of their liver to those in need. These anonymous donations may be directed to a specific recipient or nondirected, and anonymity may be one way or reciprocal. Given their unique situation, we interviewed a cohort of anonymous living liver donors and explored their opinions surrounding anonymity and its implications in living liver donation. A total of 26 anonymous donors completed a semistructured qualitative interview consisting of questions regarding their experiences as a living liver donor. The interviews were audio-recorded, transcribed, and analyzed for common themes, specifically those pertaining to the donor's perceptions and experiences with anonymity. Five main themes related to anonymity were identified: (1) the moral importance of an unencumbered gift, (2) wanting internal satisfaction rather than seeking external accolades, (3) anonymity as a protection against potential negative outcomes in the recipient, (4) feelings of ambivalence toward meeting the recipient, and (5) concerns about negative perceptions among their own friends and family. These insights into the range of donors' attitudes toward anonymity will help improve awareness and provide the best possible mental and physical care for the anonymous donor.


Asunto(s)
Trasplante de Hígado , Obtención de Tejidos y Órganos , Actitud , Humanos , Hígado , Trasplante de Hígado/efectos adversos , Donadores Vivos
5.
Clin Transplant ; 36(3): e14556, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34881451

RESUMEN

Anonymous living organ donation is an understudied but rapidly expanding sector in organ transplantation, in which donors choose to donate anonymously to a recipient in need. The family members and close support network of living donors often play a crucial role in the donation process, and their influence likely has a large impact on the decision to donate as well as the donor's physical and psychosocial state. However, there is limited data examining the impact donor families have on the anonymous donor, and in turn, the impact donation has on donors' families. To assess this, we analyzed a semi-structured qualitative interview on living donor experiences with 26 anonymous living liver donors for common themes concerning donor families. Responses surrounding donor families were grouped into three major categories: (1) family reactions to donation, ranging from (a) pride/support, (b) fear/worry, and (c) jealousy/anger; (2) the impact of donation on donor-family relationships, including (a) positive impacts, (b) negative impacts, (c) a positive ripple effect; (3) gaps in institutional support for donor families. This study provides unique information on anonymous living liver donor perceptions related to their families and will help improve existing programs to accommodate donor family needs and cater to donor relationships.


Asunto(s)
Trasplante de Hígado , Obtención de Tejidos y Órganos , Familia/psicología , Humanos , Hígado , Trasplante de Hígado/psicología , Donadores Vivos/psicología
6.
J Hepatol ; 71(5): 951-959, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31279899

RESUMEN

BACKGROUND & AIMS: Death rates on liver transplant waiting lists range from 5%-25%. Herein, we report a unique experience with 50 anonymous individuals who volunteered to address this gap by offering to donate part of their liver to a recipient with whom they had no biological connection or prior relationship, so called anonymous live liver donation (A-LLD). METHODS: Candidates were screened to confirm excellent physical, mental, social, and financial health. Demographics and surgical outcomes were analyzed. Qualitative interviews after donation examined motivation and experiences. Validated self-reported questionnaires assessed personality traits and psychological impact. RESULTS: A total of 50 A-LLD liver transplants were performed between 2005 and 2017. Most donors had a university education, a middle-class income, and a history of prior altruism. Half were women. Median age was 38.5 years (range 20-59). Thirty-three (70%) learned about this opportunity through public or social media. Saving a life, helping others, generativity, and reciprocity for past generosity were motivators. Social, financial, healthcare, and legal support in Canada were identified as facilitators. A-LLD identified most with the personality traits of agreeableness and conscientiousness. The median hospital stay was 6 days. One donor experienced a Dindo-Clavien Grade 3 complication that completely resolved. One-year recipient survival was 91% in 22 adults and 97% in 28 children. No A-LLD reported regretting their decision. CONCLUSIONS: This is the first and only report of the characteristics, motivations and facilitators of A-LLD in a large cohort. With rigorous protocols, outcomes are excellent. A-LLD has significant potential to reduce the gap between transplant organ demand and availability. LAY SUMMARY: We report a unique experience with 50 living donors who volunteered to donate to a recipient with whom they had no biological connection or prior relationship (anonymous living donors). This report is the first to discuss motivations, strategies and facilitators that may mitigate physical, social and ethical risk factors in this patient population. With rigorous protocols, anonymous liver donation and recipient outcomes are excellent; with appropriate clinical expertise and system facilitators in place, our experience suggests that other centers may consider the procedure for its significant potential to reduce the gap between transplant organ demand and availability.


Asunto(s)
Anonimización de la Información , Trasplante de Hígado/psicología , Donadores Vivos/psicología , Adolescente , Adulto , Altruismo , Canadá , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Tiempo de Internación , Trasplante de Hígado/efectos adversos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Autoinforme , Receptores de Trasplantes , Resultado del Tratamiento , Adulto Joven
7.
New Phytol ; 223(3): 1489-1504, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31066055

RESUMEN

Terpenoid-based essential oils are economically important commodities, yet beyond their biosynthetic pathways, little is known about the genetic architecture of terpene oil yield from plants. Transport, storage, evaporative loss, transcriptional regulation and precursor competition may be important contributors to this complex trait. Here, we associate 2.39 million single nucleotide polymorphisms derived from shallow whole-genome sequencing of 468 Eucalyptus polybractea individuals with 12 traits related to the overall terpene yield, eight direct measures of terpene concentration and four biomass-related traits. Our results show that in addition to terpene biosynthesis, development of secretory cavities, where terpenes are both synthesized and stored, and transport of terpenes were important components of terpene yield. For sesquiterpene concentrations, the availability of precursors in the cytosol was important. Candidate terpene synthase genes for the production of 1,8-cineole and α-pinene, and ß-pinene (which comprised > 80% of the total terpenes) were functionally characterized as a 1,8-cineole synthase and a ß/α-pinene synthase. Our results provide novel insights into the genomic architecture of terpene yield and we provide candidate genes for breeding or engineering of crops for biofuels or the production of industrially valuable terpenes.


Asunto(s)
Eucalyptus/genética , Genoma de Planta , Estudio de Asociación del Genoma Completo , Aceites de Plantas/metabolismo , Terpenos/metabolismo , Transferasas Alquil y Aril/genética , Vías Biosintéticas , Genes de Plantas , Genotipo , Patrón de Herencia/genética , Análisis Multivariante , Polimorfismo de Nucleótido Simple/genética , Sitios de Carácter Cuantitativo/genética , Reproducibilidad de los Resultados , Terpenos/química
8.
BMC Plant Biol ; 17(1): 160, 2017 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-28978322

RESUMEN

BACKGROUND: Terpene rich leaves are a characteristic of Myrtaceae. There is significant qualitative variation in the terpene profile of plants within a single species, which is observable as "chemotypes". Understanding the molecular basis of chemotypic variation will help explain how such variation is maintained in natural populations as well as allowing focussed breeding for those terpenes sought by industry. The leaves of the medicinal tea tree, Melaleuca alternifolia, are used to produce terpinen-4-ol rich tea tree oil, but there are six naturally occurring chemotypes; three cardinal chemotypes (dominated by terpinen-4-ol, terpinolene and 1,8-cineole, respectively) and three intermediates. It has been predicted that three distinct terpene synthases could be responsible for the maintenance of chemotypic variation in this species. RESULTS: We isolated and characterised the most abundant terpene synthases (TPSs) from the three cardinal chemotypes of M. alternifolia. Functional characterisation of these enzymes shows that they produce the dominant compounds in the foliar terpene profile of all six chemotypes. Using RNA-Seq, we investigated the expression of these and 24 additional putative terpene synthases in young leaves of all six chemotypes of M. alternifolia. CONCLUSIONS: Despite contributing to the variation patterns observed, variation in gene expression of the three TPS genes is not enough to explain all variation for the maintenance of chemotypes. Other candidate terpene synthases as well as other levels of regulation must also be involved. The results of this study provide novel insights into the complexity of terpene biosynthesis in natural populations of a non-model organism.


Asunto(s)
Transferasas Alquil y Aril/metabolismo , Melaleuca/enzimología , Transferasas Alquil y Aril/genética , Transferasas Alquil y Aril/aislamiento & purificación , Monoterpenos Ciclohexánicos , Ciclohexanoles/metabolismo , ADN de Plantas , Eucaliptol , Perfilación de la Expresión Génica , Genes de Plantas , Melaleuca/química , Melaleuca/genética , Monoterpenos/metabolismo , Análisis de Secuencia de ADN , Terpenos/metabolismo , Árboles/química , Árboles/enzimología
9.
Reprod Health Matters ; 25(51): 7-17, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29233076

RESUMEN

The Minimum Initial Services Package (MISP) for reproductive health has been the minimum standard for reproductive health service provision in humanitarian emergencies since 1995. Assessments of acute humanitarian settings in 2004 and 2005 revealed few MISP services in place and low knowledge of the MISP among humanitarian responders. Just 10 years later, assessments of humanitarian settings in 2013 and 2015 found largely consistent availability of MISP services and high awareness of the MISP as a standard among responders. We describe the multi-pronged strategy undertaken by the Women's Refugee Commission and other Inter-agency Working Group on Reproductive Health in Crises (IAWG) member agencies to effect systemic improvements in the availability of the MISP at the onset of humanitarian responses. We find that investments in fact-finding missions, awareness-raising, capacity development, policy harmonisation, targeted funding, emergency risk management, and community resilience-building have been critical to facilitating a sea-change in reproductive health responses in acute, large-scale emergencies. Efforts were underpinned by collaborative, inter-agency partnerships in which organisations were committed to working together to achieve shared goals. The strategies, activities, and achievements contain valuable lessons for the health sector, including reproductive health, and other sectors seeking to better integrate emerging or marginalised issues into humanitarian action.


Asunto(s)
Refugiados , Sistemas de Socorro/organización & administración , Servicios de Salud Reproductiva/organización & administración , Concienciación , Creación de Capacidad , Femenino , Humanos , Internacionalidad , Conocimiento , Políticas , Sistemas de Socorro/economía , Servicios de Salud Reproductiva/economía , Servicios de Salud Reproductiva/provisión & distribución , Salud de la Mujer
10.
Reprod Health Matters ; 25(51): 18-24, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29231788

RESUMEN

Since the 1990s, the Inter-agency field manual on reproductive health in humanitarian settings (IAFM) has provided authoritative guidance on reproductive health service provision during different phases of complex humanitarian emergencies. In 2018, the Inter-Agency Working Group on Reproductive Health in Crises will release a new edition of this global resource. In this article, we describe the collaborative and inter-sectoral revision process and highlight major changes in the 2018 IAFM. Key revisions to the manual include repositioning unintended pregnancy prevention within and explicitly incorporating safe abortion care into the Minimum Initial Service Package (MISP) chapter, which outlines a set of priority activities to be implemented at the outset of a humanitarian crisis; stronger guidance on the transition from the MISP to comprehensive sexual and reproductive health services; and the addition of a logistics chapter. In addition, the IAFM now places greater and more consistent emphasis on human rights principles and obligations, gender-based violence, and the linkages between maternal and newborn health, and incorporates a diverse range of field examples. We conclude this article with an outline of plans for releasing the 2018 IAFM and facilitating uptake by those working in refugee, crisis, conflict, and emergency settings.


Asunto(s)
Servicios de Salud Materno-Infantil/organización & administración , Refugiados , Sistemas de Socorro/organización & administración , Servicios de Salud Reproductiva/organización & administración , Naciones Unidas , Concienciación , Creación de Capacidad , Anticoncepción/métodos , Conducta Cooperativa , Femenino , Derechos Humanos , Humanos , Conocimiento , Servicios de Salud Materno-Infantil/economía , Servicios de Salud Materno-Infantil/provisión & distribución , Políticas , Sistemas de Socorro/economía , Servicios de Salud Reproductiva/economía , Servicios de Salud Reproductiva/provisión & distribución , Educación Sexual , Salud de la Mujer
11.
Reprod Health Matters ; 25(51): 103-113, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29254454

RESUMEN

During the early humanitarian response to a crisis, there is limited time to train health providers in the life-saving clinical services of the Minimum Initial Services Package (MISP) for Reproductive Health. The Training Partnership Initiative of the Inter-agency Working Group on Reproductive Health in Crises developed the S-CORT model (Sexual and reproductive health Clinical Outreach Refresher Training) for service providers operating in acute humanitarian settings and needing to rapidly refresh their knowledge and skills. Through qualitative research, this study aimed to determine the operational enablers and barriers related to the implementation of two S-CORT modules: clinical management of sexual violence survivors (CMoSVS) and manual vacuum aspiration (MVA). Across three participating countries (Burkina Faso, Nepal, and South Sudan), 135 health staff attended the CMoSVS refresher training and 94 the MVA refresher training. Results from the focus group discussions and in-depth interviews suggest that the S-CORT approach is respectful of human rights and quality of care principles. Furthermore, it is potentially effective in enhancing the knowledge and skills of existing trained service providers, strengthening their capacity, and changing their attitudes towards abortion-related services, for example. The S-CORT is a promising model for implementation in the acute phase of an emergency upon stabilisation of the security situation. The model can also be integrated into broader post-crisis capacity development efforts. Future operational research should emphasise not only an assessment of new modules' contents, but whether implementing this refresher training model in remote outreach settings is feasible, effective, and efficient.


Asunto(s)
Capacitación en Servicio/organización & administración , Sistemas de Socorro/organización & administración , Servicios de Salud Reproductiva/organización & administración , Delitos Sexuales , Legrado por Aspiración/educación , Burkina Faso , Femenino , Conocimientos, Actitudes y Práctica en Salud , Derechos Humanos , Humanos , Agencias Internacionales/organización & administración , Entrevistas como Asunto , Nepal , Embarazo , Investigación Cualitativa , Calidad de la Atención de Salud/organización & administración , Sudán del Sur , Salud de la Mujer
12.
BMC Genomics ; 16: 450, 2015 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-26062733

RESUMEN

BACKGROUND: Terpenoids are abundant in the foliage of Eucalyptus, providing the characteristic smell as well as being valuable economically and influencing ecological interactions. Quantitative and qualitative inter- and intra- specific variation of terpenes is common in eucalypts. RESULTS: The genome sequences of Eucalyptus grandis and E. globulus were mined for terpene synthase genes (TPS) and compared to other plant species. We investigated the relative expression of TPS in seven plant tissues and functionally characterized five TPS genes from E. grandis. Compared to other sequenced plant genomes, Eucalyptus grandis has the largest number of putative functional TPS genes of any sequenced plant. We discovered 113 and 106 putative functional TPS genes in E. grandis and E. globulus, respectively. All but one TPS from E. grandis were expressed in at least one of seven plant tissues examined. Genomic clusters of up to 20 genes were identified. Many TPS are expressed in tissues other than leaves which invites a re-evaluation of the function of terpenes in Eucalyptus. CONCLUSIONS: Our data indicate that terpenes in Eucalyptus may play a wider role in biotic and abiotic interactions than previously thought. Tissue specific expression is common and the possibility of stress induction needs further investigation. Phylogenetic comparison of the two investigated Eucalyptus species gives insight about recent evolution of different clades within the TPS gene family. While the majority of TPS genes occur in orthologous pairs some clades show evidence of recent gene duplication, as well as loss of function.


Asunto(s)
Transferasas Alquil y Aril/genética , Eucalyptus/enzimología , Proteínas de Plantas/genética , Transferasas Alquil y Aril/metabolismo , Eucalyptus/clasificación , Eucalyptus/genética , Evolución Molecular , Genoma de Planta , Familia de Multigenes , Filogenia , Proteínas de Plantas/metabolismo
13.
Clin Psychol Rev ; 107: 102372, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38091769

RESUMEN

Current conceptualizations of control-related beliefs in Obsessive-Compulsive Disorder (OCD) have largely been limited to beliefs about the need to control thoughts. Although growing evidence supports the notion of considering broader control-related constructs in this disorder, there has been limited research aimed at integrating findings across studies, making it difficult to determine how different control-related beliefs may influence OCD symptoms. The current review sought to systematically analyze findings from all studies investigating the relationship between control beliefs and OCD. The systematic search identified 157 eligible articles that assessed the relationship between control beliefs and OCD symptoms. Results suggested that certain control beliefs (e.g., importance of/need to control of thoughts, sense of control, beliefs about losing control) may be more closely associated with OCD than others (e.g., locus of control, and desire for control). In general, control beliefs were positively associated with OCD, with effect sizes ranging from small to large depending on the symptom domain. Based on limited studies, the only control belief which demonstrated specificity to OCD was ICT. Findings support the importance of integrating additional control beliefs in conceptualizations of OCD and provide evidence to support the benefits of targeting these beliefs in cognitive behavioural therapy.


Asunto(s)
Terapia Cognitivo-Conductual , Trastorno Obsesivo Compulsivo , Humanos , Trastorno Obsesivo Compulsivo/diagnóstico , Encuestas y Cuestionarios
14.
IEEE Open J Eng Med Biol ; 5: 534-541, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39050970

RESUMEN

Goal: This study presents a novel MRI coil design approach explicitly tailored for chick embryo measurements, with the primary objective of improving sensitivity and coverage. Methods: The limitations posed by conventional birdcage coils were addressed by introducing a curvature feature into a standard coil. The performance of the modified coil was assessed using EM simulations and experimental evaluations, which were subsequently validated using a 7 T MRI scanner. A comparative analysis was conducted against a standard quadrature low-pass birdcage coil to evaluate key factors. Results: The proposed coil demonstrated improved SNR and uniformity, particularly in the proximity of the end-rings. These results were consistent with the findings obtained from the simulations. Conclusions: The use of our innovative birdcage coil design holds promise and offers practical potential for in ovo studies.

15.
Neuro Oncol ; 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-38970818

RESUMEN

PET imaging, particularly using amino acid tracers, has become a valuable adjunct to anatomical MRI in the clinical management of patients with glioma. Collaborative international efforts have led to the development of clinical and technical guidelines for PET imaging in gliomas. The increasing readiness of statutory health insurance agencies, especially in European countries, to reimburse amino acid PET underscores its growing importance in clinical practice. Integrating artificial intelligence and radiomics in PET imaging of patients with glioma may significantly improve tumor detection, segmentation, and response assessment. Efforts are ongoing to facilitate the clinical translation of these techniques. Considerable progress in computer technology developments (eg quantum computers) may be helpful to accelerate these efforts. Next-generation PET scanners, such as long-axial field-of-view PET/CT scanners, have improved image quality and body coverage and therefore expanded the spectrum of indications for PET imaging in Neuro-Oncology (eg PET imaging of the whole spine). Encouraging results of clinical trials in patients with glioma have prompted the development of PET tracers directing therapeutically relevant targets (eg the mutant isocitrate dehydrogenase) for novel anticancer agents in gliomas to improve response assessment. In addition, the success of theranostics for the treatment of extracranial neoplasms such as neuroendocrine tumors and prostate cancer has currently prompted efforts to translate this approach to patients with glioma. These advancements highlight the evolving role of PET imaging in Neuro-Oncology, offering insights into tumor biology and treatment response, thereby informing personalized patient care. Nevertheless, these innovations warrant further validation in the near future.

16.
Arch Biochem Biophys ; 529(2): 112-21, 2013 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-23246843

RESUMEN

The essential oil of Thymus vulgaris consists of a complex blend of mono- and sesquiterpenes that provides the plant with its characteristic aromatic odor. Several chemotypes have been described for thyme. In this study, we identified two enzymes of the sabinene hydrate chemotype which are responsible for the biosynthesis of its major monoterpene alcohols, (1S,2R,4S)-(Z)-sabinene hydrate and (1S,2S,4R)-(E)-sabinene hydrate. Both TPS6 and TPS7 are multiproduct enzymes that formed 16 monoterpenes and thus cover almost the whole monoterpene spectrum of the chemotype. Although the product spectra of both enzymes are similar, they form opposing enantiomers of their chiral products. Incubation of the enzymes with the potential reaction intermediates revealed that the stereospecificity of TPS6 and TPS7 is determined by the formation of the first intermediate, linalyl diphosphate. Since TPS6 and TPS7 shared an amino acid sequence identity of 85%, a mutagenesis study was employed to identify the amino acids that determine the stereoselectivity. One amino acid position had a major influence on the stereochemistry of the formed products. Based on comparative models of TPS6 and TPS7 protein structures with the GPP substrate docked in the active site pocket, the influence of this amino acid residue on the reaction mechanism is discussed.


Asunto(s)
Liasas Intramoleculares/química , Liasas Intramoleculares/ultraestructura , Modelos Químicos , Modelos Moleculares , Monoterpenos/química , Thymus (Planta)/química , Thymus (Planta)/enzimología , Activación Enzimática , Conformación Proteica , Estereoisomerismo
17.
Cognit Ther Res ; : 1-11, 2023 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-37363745

RESUMEN

Purpose: Cognitive models of mental contamination (feelings of dirtiness/washing behaviour that arise without direct contact with a contaminant) highlight the central role of perceptions of violation in the onset and maintenance of these feelings. Little research has been done to clarify violation-specific appraisals relevant to mental contamination. Perceptions of violation of one's moral self-concept may represent one such appraisal domain. This experiment aimed to examine the impact of these appraisals on feelings of mental contamination. Methods: One hundred and fifty participants received false feedback that they scored high on a morality subscale of a bogus personality test. They then completed a writing task wherein their degree of moral self-violation was manipulated. They received a writing prompt corresponding to one of three randomly assigned conditions (violated self (VS), bolstered self (BS), general negative (GN)). Finally, participants completed measures of mental contamination. Results: The manipulation was effective at violating participants' moral self-concept. Those in the VS condition reported significantly higher levels of feelings of mental contamination than those in the BS or GN conditions. There were no significant differences between conditions regarding urges to wash. Conclusions: Findings highlight the relevance of moral self-violation in the understanding and treatment of mental contamination.

18.
Transplant Proc ; 55(2): 274-278, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36822887

RESUMEN

The Gift of Life metaphor is prevalent in pro-donation dialogue, aiming to promote transplant programs and conceptualize the act of organ donation. To obtain a better understanding of living donor perceptions on the term Gift of Life, we analyzed thematic views presented by anonymous living donors (ALLDs). Twenty-six ALLDs completed a semi-structured qualitative interview consisting of questions regarding their motivations, experiences, and perceptions on donation. The following 5 major themes relating to the Gift of Life terminology were elucidated: (1) Complete agreement with the term and its relevance to donation. (2) Their donation did not represent a Gift of Life. (3) The term was too grandiose. (4)A belief that the term has more meaning for the recipient rather than donor. (5 )That the "gift" goes both ways, with the donor also benefiting from the experience.


Asunto(s)
Trasplante de Riñón , Obtención de Tejidos y Órganos , Humanos , Altruismo , Donadores Vivos , Hígado , Donaciones
19.
BMC Plant Biol ; 12: 84, 2012 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-22682202

RESUMEN

BACKGROUND: The essential oil of chamomile, one of the oldest and agronomically most important medicinal plant species in Europe, has significant antiphlogistic, spasmolytic and antimicrobial activities. It is rich in chamazulene, a pharmaceutically active compound spontaneously formed during steam distillation from the sesquiterpene lactone matricine. Chamomile oil also contains sesquiterpene alcohols and hydrocarbons which are produced by the action of terpene synthases (TPS), the key enzymes in constructing terpene carbon skeletons. RESULTS: Here, we present the identification and characterization of five TPS enzymes contributing to terpene biosynthesis in chamomile (Matricaria recutita). Four of these enzymes were exclusively expressed in above-ground organs and produced the common terpene hydrocarbons (-)-(E)-ß-caryophyllene (MrTPS1), (+)-germacrene A (MrTPS3), (E)-ß-ocimene (MrTPS4) and (-)-germacrene D (MrTPS5). A fifth TPS, the multiproduct enzyme MrTPS2, was mainly expressed in roots and formed several Asteraceae-specific tricyclic sesquiterpenes with (-)-α-isocomene being the major product. The TPS transcript accumulation patterns in different organs of chamomile were consistent with the abundance of the corresponding TPS products isolated from these organs suggesting that the spatial regulation of TPS gene expression qualitatively contribute to terpene composition. CONCLUSIONS: The terpene synthases characterized in this study are involved in the organ-specific formation of essential oils in chamomile. While the products of MrTPS1, MrTPS2, MrTPS4 and MrTPS5 accumulate in the oils without further chemical alterations, (+)-germacrene A produced by MrTPS3 accumulates only in trace amounts, indicating that it is converted into another compound like matricine. Thus, MrTPS3, but also the other TPS genes, are good markers for further breeding of chamomile cultivars rich in pharmaceutically active essential oils.


Asunto(s)
Transferasas Alquil y Aril/genética , Manzanilla/enzimología , Aceites Volátiles/metabolismo , Componentes Aéreos de las Plantas/enzimología , Raíces de Plantas/enzimología , Terpenos/metabolismo , Transferasas Alquil y Aril/metabolismo , Secuencia de Aminoácidos , Manzanilla/química , Manzanilla/genética , Clonación Molecular , Regulación de la Expresión Génica de las Plantas/genética , Lactonas/química , Lactonas/metabolismo , Datos de Secuencia Molecular , Especificidad de Órganos , Filogenia , Componentes Aéreos de las Plantas/química , Componentes Aéreos de las Plantas/genética , Aceites de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/química , Raíces de Plantas/genética , Alineación de Secuencia , Terpenos/química
20.
Disabil Rehabil ; 44(8): 1328-1332, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-32755398

RESUMEN

PURPOSE: Post-traumatic growth (PTG) is positive change that occurs after struggling with challenging life crises. Research on PTG has typically been limited to oncology populations, first-responders, and individuals in warzones. We report the experience of PTG amongst a sample of 26 anonymous live liver donors. METHODS: Anonymous donors were those with no biological connection or prior relationship with recipients. Twenty-six participants participated in a semi-structured qualitative interview examining their experience with, and outcomes of donation. Interview transcripts were analyzed for themes about PTG using the constant comparison method. RESULTS: While some donors indicated that donation had little lasting impact on their life, most cited significant personal and interpersonal changes resulting from the experience. The most common positive changes included deepened bonds with others, appreciation for personal strength, clearer life direction, legacy-building, and a connection to the transplant community. CONCLUSION: Despite the short-term physical trauma of living donor surgery, the act of anonymous donation appeared to be a catalyst for positive long-term psychological growth. These findings help to bolster the ethical argument in favour of anonymous donation.IMPLICATIONS FOR REHABILITATIONThere is a shortage of organ donors for recipients in need, and anonymous living liver donors can successfully reduce wait times and mortality rates for those on wait lists.There are some questions about the ethics of anonymous donation due to possible negative physical and psychological effects of donation surgery on donors.In a qualitative study, this study shows that donors ascribe significant meaning to, and derive many psychological benefits from, their donation experience.These findings provide insights about how to best support anonymous donors through and after their donation experience.


Asunto(s)
Trasplante de Hígado , Crecimiento Psicológico Postraumático , Humanos , Hígado , Trasplante de Hígado/psicología , Donadores Vivos/psicología , Listas de Espera
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