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1.
Plant Biotechnol J ; 20(2): 374-389, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34614273

RESUMO

Vegetative storage proteins (VSPs) are known to serve as nitrogen reserves in many dicot plants but remain undiscovered in grasses, most widely grown group of crops globally. We identified and characterized a VSP in maize and demonstrated that its overexpression improved drought tolerance. Nitrogen supplementation selectively induced a mesophyll lipoxygenase (ZmLOX6), which was targeted to chloroplasts by a novel N-terminal transit peptide of 62 amino acids. When ectopically expressed under the control of various tissue-specific promoters, it accumulated to a fivefold higher level upon expression in the mesophyll cells than the wild-type plants. Constitutive expression or targeted expression specifically to the bundle sheath cells increased its accumulation by less than twofold. The overexpressed ZmLOX6 was remobilized from the leaves like other major proteins during grain development. Evaluated in the field over locations and years, transgenic hybrids overexpressing ZmLOX6 in the mesophyll cells significantly outyielded nontransgenic sibs under managed drought stress imposed at flowering. Additional storage of nitrogen as a VSP in maize leaves ameliorated the effect of drought on grain yield.


Assuntos
Secas , Zea mays , Cloroplastos , Grão Comestível/genética , Nitrogênio/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Zea mays/genética
2.
BMC Evol Biol ; 20(1): 156, 2020 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-33228518

RESUMO

BACKGROUND: Ecdysozoa are the moulting protostomes, including arthropods, tardigrades, and nematodes. Both the molecular and fossil records indicate that Ecdysozoa is an ancient group originating in the terminal Proterozoic, and exceptional fossil biotas show their dominance and diversity at the beginning of the Phanerozoic. However, the nature of the ecdysozoan common ancestor has been difficult to ascertain due to the extreme morphological diversity of extant Ecdysozoa, and the lack of early diverging taxa in ancient fossil biotas. RESULTS: Here we re-describe Acosmia maotiania from the early Cambrian Chengjiang Biota of Yunnan Province, China and assign it to stem group Ecdysozoa. Acosmia features a two-part body, with an anterior proboscis bearing a terminal mouth and muscular pharynx, and a posterior annulated trunk with a through gut. Morphological phylogenetic analyses of the protostomes using parsimony, maximum likelihood and Bayesian inference, with coding informed by published experimental decay studies, each placed Acosmia as sister taxon to Cycloneuralia + Panarthropoda-i.e. stem group Ecdysozoa. Ancestral state probabilities were calculated for key ecdysozoan nodes, in order to test characters inferred from fossils to be ancestral for Ecdysozoa. Results support an ancestor of crown group ecdysozoans sharing an annulated vermiform body with a terminal mouth like Acosmia, but also possessing the pharyngeal armature and circumoral structures characteristic of Cambrian cycloneuralians and lobopodians. CONCLUSIONS: Acosmia is the first taxon placed in the ecdysozoan stem group and provides a constraint to test hypotheses on the early evolution of Ecdysozoa. Our study suggests acquisition of pharyngeal armature, and therefore a change in feeding strategy (e.g. predation), may have characterised the origin and radiation of crown group ecdysozoans from Acosmia-like ancestors.


Assuntos
Fósseis , Invertebrados , Filogenia , Animais , Artrópodes/anatomia & histologia , Artrópodes/classificação , Teorema de Bayes , China , Invertebrados/anatomia & histologia , Invertebrados/classificação , Nematoides/anatomia & histologia , Nematoides/classificação , Tardígrados/anatomia & histologia , Tardígrados/classificação
3.
Clin Transplant ; 34(6): e13882, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32294274

RESUMO

Twenty percent of kidneys recovered for transplantation are discarded. The most common reason for not transplanting these kidneys is to organ quality and biopsy findings. Yet, organ quality measures are not associated with discard rates and kidneys with poorer quality measures lead to greater life span for the recipient compared to staying on dialysis. Biopsy findings are not correlated with graft survival in most cases. The risk aversion of transplant centers from using "high-risk" kidneys can be, in part at least, attributed to negative consequences of poor graft survival with possible program sanctions or possible loss of insurance contracts. CMS has taken a first step by eliminating short-term graft survival as a performance measure for transplant centers. Many of the discarded kidneys will provide good results if transplanted and would recognize that patients value getting a transplant above graft survival.


Assuntos
Transplante de Rim , Obtenção de Tecidos e Órgãos , Seleção do Doador , Sobrevivência de Enxerto , Humanos , Fatores de Risco , Doadores de Tecidos
4.
Plant Physiol ; 166(3): 1162-76, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25192697

RESUMO

With an optimized expression cassette consisting of the soybean (Glycine max) native promoter modified for enhanced expression driving a chimeric gene coding for the soybean native amino-terminal 86 amino acids fused to an insensitive shuffled variant of maize (Zea mays) 4-hydroxyphenylpyruvate dioxygenase (HPPD), we achieved field tolerance in transgenic soybean plants to the HPPD-inhibiting herbicides mesotrione, isoxaflutole, and tembotrione. Directed evolution of maize HPPD was accomplished by progressively incorporating amino acids from naturally occurring diversity and novel substitutions identified by saturation mutagenesis, combined at random through shuffling. Localization of heterologously expressed HPPD mimicked that of the native enzyme, which was shown to be dually targeted to chloroplasts and the cytosol. Analysis of the native soybean HPPD gene revealed two transcription start sites, leading to transcripts encoding two HPPD polypeptides. The N-terminal region of the longer encoded peptide directs proteins to the chloroplast, while the short form remains in the cytosol. In contrast, maize HPPD was found almost exclusively in chloroplasts. Evolved HPPD enzymes showed insensitivity to five inhibitor herbicides. In 2013 field trials, transgenic soybean events made with optimized promoter and HPPD variant expression cassettes were tested with three herbicides and showed tolerance to four times the labeled rates of mesotrione and isoxaflutole and two times the labeled rates of tembotrione.


Assuntos
4-Hidroxifenilpiruvato Dioxigenase/antagonistas & inibidores , Glycine max/enzimologia , Herbicidas/farmacologia , 4-Hidroxifenilpiruvato Dioxigenase/genética , 4-Hidroxifenilpiruvato Dioxigenase/metabolismo , Sequência de Aminoácidos , Cicloexanonas/química , Cicloexanonas/farmacologia , Expressão Gênica , Herbicidas/química , Isoxazóis , Dados de Sequência Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Alinhamento de Sequência , Glycine max/efeitos dos fármacos , Glycine max/genética
5.
J Exp Bot ; 65(1): 249-60, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24218327

RESUMO

Crop improvement for yield and drought tolerance is challenging due to the complex genetic nature of these traits and environmental dependencies. This study reports that transgenic over-expression of Zea mays AR GOS1 (ZAR1) enhanced maize organ growth, grain yield, and drought-stress tolerance. The ZAR1 transgene exhibited environmental interactions, with yield increase under Temperate Dry and yield reduction under Temperate Humid or High Latitude environments. Native ZAR1 allele variation associated with drought-stress tolerance. Two founder alleles identified in the mid-maturity germplasm of North America now predominate in Pioneer's modern breeding programme, and have distinct proteins, promoters and expression patterns. These two major alleles show heterotic group partitioning, with one predominant in Pioneer's female and the other in the male heterotic groups, respectively. These two alleles also associate with favourable crop performance when heterozygous. Allele-specific transgene testing showed that, of the two alleles discussed here, each allele differed in their impact on yield and environmental interactions. Moreover, when transgenically stacked together the allelic pair showed yield and environmental performance advantages over either single allele, resembling heterosis effects. This work demonstrates differences in transgenic efficacy of native alleles and the differences reflect their association with hybrid breeding performance.


Assuntos
Vigor Híbrido , Proteínas de Plantas/genética , Zea mays/genética , Alelos , Sequência de Bases , Biomassa , Cruzamento , Secas , Expressão Gênica , Interação Gene-Ambiente , Variação Genética , Haplótipos , Dados de Sequência Molecular , Família Multigênica , Fenótipo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/fisiologia , Análise de Sequência de DNA , Transgenes , Zea mays/crescimento & desenvolvimento , Zea mays/fisiologia
6.
Plant Cell ; 22(4): 1057-73, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20400678

RESUMO

Genes involved in cell number regulation may affect plant growth and organ size and, ultimately, crop yield. The tomato (genus Solanum) fruit weight gene fw2.2, for instance, governs a quantitative trait locus that accounts for 30% of fruit size variation, with increased fruit size chiefly due to increased carpel ovary cell number. To expand investigation of how related genes may impact other crop plant or organ sizes, we identified the maize (Zea mays) gene family of putative fw2.2 orthologs, naming them Cell Number Regulator (CNR) genes. This family represents an ancient eukaryotic family of Cys-rich proteins containing the PLAC8 or DUF614 conserved motif. We focused on native expression and transgene analysis of the two maize members closest to Le-fw2.2, namely, CNR1 and CNR2. We show that CNR1 reduced overall plant size when ectopically overexpressed and that plant and organ size increased when its expression was cosuppressed or silenced. Leaf epidermal cell counts showed that the increased or decreased transgenic plant and organ size was due to changes in cell number, not cell size. CNR2 expression was found to be negatively correlated with tissue growth activity and hybrid seedling vigor. The effects of CNR1 on plant size and cell number are reminiscent of heterosis, which also increases plant size primarily through increased cell number. Regardless of whether CNRs and other cell number-influencing genes directly contribute to, or merely mimic, heterosis, they may aid generation of more vigorous and productive crop plants.


Assuntos
Proteínas de Plantas/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/genética , Biomassa , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , DNA Bacteriano/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Vigor Híbrido , Modelos Moleculares , Família Multigênica , Fenótipo , Filogenia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , RNA de Plantas/genética , Alinhamento de Sequência
7.
Prog Transplant ; 22(1): 6-16; quiz 17, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22489438

RESUMO

The historical development of deceased organ donation, transplantation, and organ procurement organizations is reviewed. The concept of transplantation, taking parts from one animal or person and putting them into another animal or person, is ancient. The development of organ transplantation brought on the need for a source of organs. Although many early kidney transplants used kidneys from living donors, these donors could not satisfy the ever-growing need for organs, and extrarenal organs were recovered only from deceased donors. This need for organs to satisfy the great demand led to specialized organizations to identify deceased donors, manage them until recovery occurred, and to notify transplant centers that organs were available for their patients. The functions of these organ procurement organizations expanded to include other required functions such as education, accounting, and compliance with state and federal requirements. Because of the shortage of organs relative to the demand, lack of a unified organ allocation system, the perception that organs are a national resource and should be governed by national regulations, and to improve results of organ procurement organizations and transplant centers, the federal government has regulated virtually all phases of organ procurement and transplantation.


Assuntos
Transplante de Órgãos/história , Obtenção de Tecidos e Órgãos/história , História do Século XX , Humanos , Transplante de Órgãos/legislação & jurisprudência , Obtenção de Tecidos e Órgãos/organização & administração
8.
Biology (Basel) ; 11(10)2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36290419

RESUMO

Arthropods, the most diverse form of macroscopic life in the history of the Earth, originated in the sea. Since the early Cambrian, at least ~518 million years ago, these animals have dominated the oceans of the world. By the Silurian-Devonian, the fossil record attests to arthropods becoming the first animals to colonize land, However, a growing body of molecular dating and palaeontological evidence suggests that the three major terrestrial arthropod groups (myriapods, hexapods, and arachnids), as well as vascular plants, may have invaded land as early as the Cambrian-Ordovician. These dates precede the oldest fossil evidence of those groups and suggest an unrecorded continental "Cambrian explosion" a hundred million years prior to the formation of early complex terrestrial ecosystems in the Silurian-Devonian. We review the palaeontological, phylogenomic, and molecular clock evidence pertaining to the proposed Cambrian terrestrialization of the arthropods. We argue that despite the challenges posed by incomplete preservation and the scarcity of early Palaeozoic terrestrial deposits, the discrepancy between molecular clock estimates and the fossil record is narrower than is often claimed. We discuss strategies for closing the gap between molecular clock estimates and fossil data in the evolution of early ecosystems on land.

9.
Mol Plant Microbe Interact ; 23(1): 6-16, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19958134

RESUMO

Fusarium kernel rot disease starburst symptomatology was characterized fully for the first time. Two maize lines were hand pollinated and inoculated, using a fluorescent protein-expressing transformant of the fungal pathogen Fusarium verticillioides, by introduction of a conidial suspension through the silk channel of intact ears. Microscopy was used to identify the infection court and document initial stages of kernel colonization and subsequent manifestation of macroscopic symptoms. The fungus entered kernels of susceptible line AD38 via an open stylar canal and spread extracellularly and over the kernel through the nucellus region, sporadically entering pericarp and filling the long thick-walled mesocarp cells. Hyphae spread within pericarp from cell to cell via pits, colonizing files of host cells by growing both up and down the kernel in a radial pattern that preceded macroscopic symptom development. The starburst symptom developed subsequently, and mirrored colonization exactly, when there was extensive dissolution of the thick walls of pericarp cells. Line HT1 exhibited a closed stylar canal phenotype and was not susceptible-except when the pericarp surface was breached mechanically. We hypothesize the passive movement of conidia along the surface of silks, perhaps via capillarity, as a possible mechanism for pathogen access to the infection court.


Assuntos
Fusarium/fisiologia , Interações Hospedeiro-Patógeno/fisiologia , Zea mays/microbiologia , Microscopia Crioeletrônica , Fusarium/crescimento & desenvolvimento , Fusarium/ultraestrutura , Hifas/crescimento & desenvolvimento , Hifas/ultraestrutura , Fenótipo , Doenças das Plantas/microbiologia
10.
Clin Transplant ; 24(4): 493-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19788451

RESUMO

Some family members initiate organ donation discussions before being approached by donor coordinators or healthcare providers. We examined differences between families that did vs. did not initiate organ donation discussions and factors predicting donation consent among those families that self-initiated the discussion. Next-of-kin of donor-eligible individuals (147 donors, 138 non-donors) from one organ procurement organization completed a telephone interview. Seventy-three families (25.6%) first mentioned organ donation, and 54 (74%) of them consented to donation. Several characteristics of the deceased and next-of-kin were associated with whether family members initiated the donation discussion with donation coordinators or healthcare providers. Moreover, family mention of donation was more likely to yield consent when the deceased was younger (OR=0.95, CI=0.92-0.99), next-of-kin was a registered donor (OR=3.86, CI=2.84-6.76), and when family was more satisfied with the healthcare team (OR=1.20, CI=1.04-1.39). Knowing the deceased's donation intentions and being exposed to positive organ donation messages are more likely to trigger families to raise donation with providers. Organ procurement organizations (OPOs) and healthcare providers should work collaboratively to develop strategies for how best to respond to families who initiate this conversation.


Assuntos
Tomada de Decisões , Família/psicologia , Doadores de Tecidos/psicologia , Obtenção de Tecidos e Órgãos , Adulto , Criança , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade
11.
Curr Biol ; 30(8): 1529-1536.e2, 2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32109391

RESUMO

Facivermis yunnanicus [1, 2] is an enigmatic worm-like animal from the early Cambrian Chengjiang Biota of Yunnan Province, China. It is a small (<10 cm) bilaterian with five pairs of spiny anterior arms, an elongated body, and a swollen posterior end. The unusual morphology of Facivermis has prompted a history of diverse taxonomic interpretations, including among annelids [1, 3], lophophorates [4], and pentastomids [5]. However, in other studies, Facivermis is considered to be more similar to lobopodians [2, 6-8]-the fossil grade from which modern panarthropods (arthropods, onychophorans, and tardigrades) are derived. In these studies, Facivermis is thought to be intermediate between cycloneuralian worms and lobopodians. Facivermis has therefore been suggested to represent an early endobenthic-epibenthic panarthropod transition [6] and to provide crucial insights into the origin of paired appendages [2]. However, the systematic affinity of Facivermis was poorly supported in a previous phylogeny [6], partially due to incomplete understanding of its morphology. Therefore, the evolutionary significance of Facivermis remains unresolved. In this study, we re-examine Facivermis from new material and the holotype, leading to the discovery of several new morphological features, such as paired eyes on the head and a dwelling tube. Comprehensive phylogenetic analyses using parsimony, Bayesian inference, and maximum likelihood all support Facivermis as a luolishaniid in a derived position within the onychophoran stem group rather than as a basal panarthropod. In contrast to previous studies, we therefore conclude that Facivermis provides a rare early Cambrian example of secondary loss to accommodate a highly specialized tube-dwelling lifestyle.


Assuntos
Fósseis/anatomia & histologia , Invertebrados/classificação , Características de História de Vida , Animais , Evolução Biológica , China , Fósseis/ultraestrutura , Invertebrados/anatomia & histologia , Invertebrados/fisiologia , Microscopia Eletrônica de Varredura
12.
Arthropod Struct Dev ; 59: 100997, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33039753

RESUMO

The majority of extant arachnids are terrestrial, but other chelicerates are generally aquatic, including horseshoe crabs, sea spiders, and the extinct eurypterids. It is necessary to determine whether arachnids are exclusively descended from a single common ancestor (monophyly), because only that relationship is compatible with one land colonisation in chelicerate evolutionary history. Some studies have cast doubt on arachnid monophyly and recast the origins of their terrestrialization. These include some phylogenomic analyses placing horseshoe crabs within Arachnida, and from aquatic Palaeozoic stem-group scorpions. Here, we evaluate the possibility of arachnid monophyly by considering morphology, fossils and molecules holistically. We argue arachnid monophyly obviates the need to posit reacquisition/retention of aquatic characters such as gnathobasic feeding and book gills without trabeculae from terrestrial ancestors in horseshoe crabs, and that the scorpion total-group contains few aquatic taxa. We built a matrix composed of 200 slowly-evolving genes and re-analysed two published molecular datasets. We retrieved arachnid monophyly where other studies did not - highlighting the difficulty of resolving chelicerate relationships from current molecular data. As such, we consider arachnid monophyly the best-supported hypothesis. Finally, we inferred that arachnids terrestrialized during the Cambrian-Ordovician using the slow-evolving molecular matrix, in agreement with recent analyses.


Assuntos
Aracnídeos/anatomia & histologia , Evolução Biológica , Filogenia , Animais , Aracnídeos/genética , Evolução Molecular , Fósseis/anatomia & histologia
13.
Clin Transplant ; 23(6): 778-83, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20447183

RESUMO

The Health Resources and Services Administration launched collaboratives with the goals of increasing donation rates, increasing the number of organs transplanted, eliminating deaths on the waiting list and improving outcomes. The Center for Medicare and Medicaid Services (CMS) recently published requirements for organ procurement organizations (OPOs) and transplant centers. Failure to meet CMS performance measures could result in OPOs losing their service area or transplant centers losing their CMS certification. CMS uses analyses by the Scientific Registry of Transplant Recipients (SRTR) to evaluate a transplant center's performance based on risk-adjusted outcomes. However, CMS also uses a more liberal (one-sided) statistical test rendering more centers likely to qualify as low performing. Furthermore, the SRTR model does not incorporate some important patient variables in its statistical model which may result in biased determinations of quality of care. Cumulatively, there is much unexplained variation for transplant outcomes as suggested by the low predictive ability of survival models compared to other disease contexts. OPOs and transplant centers are unlikely to quietly accept their elimination. They may take certain steps that can result in exclusion of candidates who might otherwise benefit from transplantation and/or result in fewer transplants through restricted use of organs thought to carry higher risk of failure. CMS should join with transplant organizations to ensure that the goals of the collaborative are not inhibited by their performance measures.


Assuntos
Centers for Medicare and Medicaid Services, U.S./economia , Centers for Medicare and Medicaid Services, U.S./legislação & jurisprudência , Medicaid/economia , Medicare/economia , Transplante de Órgãos/economia , Obtenção de Tecidos e Órgãos , Humanos , Transplante de Órgãos/legislação & jurisprudência , Estados Unidos
14.
Prog Transplant ; 19(2): 173-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19588668

RESUMO

CONTEXT: Public education campaigns about organ donation are common, but their association to actual attitudes, beliefs, and decisions about organ donation among family members of donation-eligible individuals is unknown. OBJECTIVE: To examine the sources of organ donation information identified by donor and nondonor families who participated in a large-scale study to examine factors that influence organ donation decisions. DESIGN: Semistructured telephone survey conducted after a passive recruitment strategy. SETTING AND PARTICIPANTS: Participants were 285 next of kin of donor-eligible individuals (147 donors, 138 nondonors) from one organ procurement organization. RESULTS: Most (85.6%) of next of kin were exposed to at least 1 source of donation information that was important to them, although the types of donation information they were exposed to varied widely. White and educated adults were more likely to have been exposed to more donation information than had minorities and persons with less education. Favorable attitudes and beliefs about organ donation, donor designation, and sharing donation intentions with others were all associated with more exposure to different types of donation information. Donation consent was more likely when next of kin had been exposed to more donation information in the months preceding the family member's death. CONCLUSIONS: When examined in the context of other recent research, these findings argue for continued development and implementation of public education campaigns for organ donation, with an emphasis on repeated exposure over time.


Assuntos
Atitude Frente a Saúde , Tomada de Decisões , Família/psicologia , Educação em Saúde/organização & administração , Conhecimentos, Atitudes e Prática em Saúde , Obtenção de Tecidos e Órgãos , Negro ou Afro-Americano/educação , Negro ou Afro-Americano/psicologia , Análise de Variância , Estudos Transversais , Escolaridade , Feminino , Florida , Humanos , Disseminação de Informação , Masculino , Meios de Comunicação de Massa , Pessoa de Meia-Idade , Pesquisa Metodológica em Enfermagem , Inquéritos e Questionários , Consentimento do Representante Legal , População Branca/educação , População Branca/psicologia
15.
Transplantation ; 85(7): 986-91, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18408579

RESUMO

BACKGROUND: Ureteral stent placement at kidney transplantation may reduce stenosis or leakage (S/L) complication rates. However, stent placement may also increase risk for early urinary tract infection (early UTI; <3 months after transplant) and BK virus allograft nephropathy (BKVAN). In children, the usefulness of stent placement is not well defined. METHODS: We analyzed retrospective data from children transplanted at our center for the three above outcomes in relation to stents. At our center, stent placement decision is driven by surgeon preference. RESULTS: Among 129 transplants from 1996 to 2006, early UTI was seen in 9.3% and S/L in 4.6%. By univariate analyses, stent placement was a significant risk factor for early UTI (P=0.0399) but not protective for S/L (P=0.23). In multivariate analyses, stent placement, human leukocyte antigen match, and bladder augmentation increased the odds ratio for early UTI. Only deceased donor source increased the odds ratio for S/L. In a truncated data set from 1999 to 2006, BKVAN occurred in 9 of 93 (9.6%). Per minute increase in warm ischemia time was the only significant risk factor for BKVAN by both univariate and Cox regression analyses. Stent placement did not improve graft survival (P=0.5726) but required general anesthesia for removal in the operating room, leading to additional cost and potential risk. CONCLUSION: Routine stent placement in children in this era of low urological complication rates and BKVAN needs reevaluation.


Assuntos
Transplante de Rim/métodos , Stents , Ureter/cirurgia , Adolescente , Adulto , Idoso , Cadáver , Criança , Pré-Escolar , Feminino , Sobrevivência de Enxerto , Antígenos HLA/análise , Humanos , Lactente , Transplante de Rim/imunologia , Transplante de Rim/fisiologia , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Doadores de Tecidos/estatística & dados numéricos , Bexiga Urinária/cirurgia
16.
Transplantation ; 85(1): 1-6, 2008 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-18192903

RESUMO

Timely access to transplantation for eligible patients with end-stage renal disease (ESRD) is critical. However, pressures exist to improve efficiencies in transplantation and to achieve high center performance ratings, including the recently submitted "Final Rule" by Center for Medicare and Medicaid Services. This policy may affect the availability of public funding for as many as 10% of kidney transplant centers in the United States. This study examined adult solitary kidney transplant candidates from 1995 to 2005 using a national database. Mortality rates were calculated for candidates at individual centers prior to transplantation. Posttransplant survival and center's standardized mortality ratios were then calculated and compared to rates of candidate mortality. Candidate mortality rates varied substantially across centers (highest quartile with almost 2-fold elevated mortality). Recipients at centers with the highest candidate mortality rates had approximately 1.9 years reduced median graft survival for deceased donor transplants and decreased patient survival even after risk adjustment (adjusted hazard ratio=1.33, 95% confidence interval 1.25-1.41). This association was greater among living transplants (adjusted hazard ratio=1.49, 95% confidence interval 1.31-1.70). For 1-year outcomes, 19% (43/224) of centers met criteria for low performance for either graft loss or patient death in living or deceased donor transplants. Of these, 51% were among centers with the highest candidate mortality as compared to 7% of centers with the lowest candidate mortality. The health status of centers' transplant candidate pool is a significant determinant of outcomes and performance ratings. Centers with a higher risk candidate pool are significantly more likely to be identified for poor performance and could potentially lose public funding. Pressures to enhance outcomes may lead centers to exclude high-risk but otherwise viable transplant candidates.


Assuntos
Transplante de Rim/mortalidade , Mortalidade/tendências , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Feminino , Sobrevivência de Enxerto , Instalações de Saúde/normas , Administração de Instituições de Saúde , Nível de Saúde , Humanos , Falência Renal Crônica/cirurgia , Masculino , Medicaid/estatística & dados numéricos , Medicaid/tendências , Medicare/estatística & dados numéricos , Medicare/tendências , Seleção de Pacientes , Qualidade de Vida , Estudos Retrospectivos , Risco Ajustado , Taxa de Sobrevida/tendências , Transplante , Resultado do Tratamento , Estados Unidos
17.
Transplantation ; 85(9): 1230-4, 2008 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18475176

RESUMO

We report on the initial development and validation of the Living Donation Expectancies Questionnaire (LDEQ), designed to measure the expectations of living kidney donor candidates. Potential living donors (n=443) at two transplant centers were administered the LDEQ and other questionnaires, and their medical records were reviewed. Factor analysis provides support for six LDEQ scales: Interpersonal Benefit, Personal Growth, Spiritual Growth, Quid Pro Quo, Health Consequences, and Miscellaneous Consequences. All but one scale showed good internal consistency. Expected benefits of donation were associated with higher optimism and lower mental health; expected consequences of donation were associated with lower optimism and lower physical and mental health. More potential donors with relative or absolute contraindications had high Interpersonal Benefit (P<0.0001), Personal Growth (P<0.01), Quid Pro Quo (P<0.0001), and Health Consequences (P<0.0001) expectations. The LDEQ has promise in evaluating donor candidates' expectations.


Assuntos
Rim , Doadores Vivos/psicologia , Nefrectomia/psicologia , Adulto , Família , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria/métodos , Reprodutibilidade dos Testes , Fatores Socioeconômicos , Inquéritos e Questionários , Coleta de Tecidos e Órgãos/psicologia
18.
Am J Kidney Dis ; 51(4): 663-70, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18371542

RESUMO

BACKGROUND: Blacks are disproportionately affected by chronic kidney disease, but are far less likely to undergo live donor kidney transplantation (LDKT) than whites. We assessed the differential effectiveness in blacks and whites of a home-based (HB) LDKT educational approach. STUDY DESIGN: A planned secondary analysis of a previously published randomized trial. SETTING & PARTICIPANTS: 132 patients (60 black, 72 white) approved for kidney transplantation at 1 kidney transplant center in the southeastern United States. INTERVENTION: Assignment to receive either standard clinic-based (CB) transplant education (n = 69) or CB plus an HB (CB + HB) LDKT education program (n = 63). The HB education program was culturally sensitive for blacks, including using a minority health educator, brochures that highlight minority transplant recipients and donors, and discussion of race-specific outcome data. OUTCOMES: Primary outcomes were proportions of patients with live donor inquiries, evaluations, and transplants 1 year after study participation. MEASUREMENTS: Medical record and questionnaire data. RESULTS: 69 patients were assigned to the CB group, and 63 to the CB + HB group. After 1 year, there were 96 living donor inquiries (72.7%), 62 living donor evaluations (47.0%), and 54 LDKTs (40.9%). Patients assigned to the CB + HB group were more likely to have had living donor inquiries (odds ratio [OR], 1.7; confidence interval [CI], 1.2 to 3.0), a living donor evaluated (OR, 2.7; CI, 1.4 to 5.4), and LDKT (OR, 3.0; CI, 1.5 to 5.9). The effect was greater in blacks than whites for living donor evaluations and LDKT, but not for living donor inquiries (treatment-by-race interaction, P < 0.001, P < 0.001, and P = 0.8, respectively). Blacks in the CB + HB group were more likely to have had at least 1 living donor inquiry (51.7% versus 77.4%), at least 1 living donor evaluated (17.2% versus 48.4%), and LDKT (13.8% versus 45.2%) than those in the CB group. By comparison, whites in the CB + HB group were more likely to have had at least 1 living donor inquiry (72.5% versus 87.5%), at least 1 living donor evaluated (47.5% versus 71.9%), and LDKT (42.5% versus 59.4%) than those in the CB group. LIMITATIONS: Single-center study with greater dropout rate in the CB + HB group. CONCLUSIONS: These results suggest that a culturally sensitive LDKT education program that reaches out to blacks and their social support network can overcome some barriers to LDKT in this population.


Assuntos
Negro ou Afro-Americano , Educação em Saúde/métodos , Transplante de Rim , Doadores Vivos/educação , Doadores Vivos/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/métodos , Obtenção de Tecidos e Órgãos/estatística & dados numéricos , População Branca , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Pediatr Crit Care Med ; 9(2): 180-5, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18477931

RESUMO

OBJECTIVE: To identify factors that influence parents' decisions when asked to donate a deceased child's organs. DESIGN: Cross-sectional design with data collection via structured telephone interviews. SETTING: One organ procurement organization in the Southeastern United States. PARTICIPANTS: Seventy-four parents (49 donors, 25 nondonors) of donor-eligible deceased children who were previously approached by coordinators from one organ procurement organization in the southeastern United States. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Multivariate analyses showed that organ donation was more likely when the parent was a registered organ donor (odds ratio [OR] = 1.4, confidence interval [CI] = 1.1, 2.7), the parent had favorable organ donation beliefs (OR = 5.5, CI = 2.7, 12.3), the parent was exposed to organ donation information before the child's death (OR = 2.6, CI = 1.7, 10.3), a member of the child's healthcare team first mentioned organ donation (OR = 1.4, CI = 1.2, 3.7), the requestor was perceived as sensitive to the family's needs (OR = 0.4, CI = 0.2, 0.7), the family had sufficient time to discuss donation (OR = 5.2, CI = 1.4, 11.6), and family members were in agreement about donation (OR = 2.8, CI = 1.3, 5.2). CONCLUSIONS: This study identifies several modifiable variables that influence the donation decision-making process for parents. Strategies to facilitate targeted organ donation education and higher consent rates are discussed.


Assuntos
Tomada de Decisões , Hospitais Pediátricos , Pais/psicologia , Obtenção de Tecidos e Órgãos , Adolescente , Adulto , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Lactente , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Sudeste dos Estados Unidos
20.
Prog Transplant ; 18(1): 13-6, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18429576

RESUMO

Signed donor cards clearly demonstrate the donor's intention to donate organs after death. In many states, this donation cannot be rescinded by the next of kin, and organs can be recovered from the donor even if the family objects. The family usually does not object if the donor has signed an organ donor card, especially if the donor had discussed the issue with the family. In some situations, however, the family objects to donation despite the signed organ donor card. If the organ procurement organization pursues donation, adverse publicity and even legal action are possible. It can be a challenge for organ procurement personnel to deal with families who object to donation in the face of a signed organ donor card in a manner that will lead to successful organ recovery without adverse consequences. This article describes 4 cases where the donor had a signed organ donor card but the family initially objected to donation. Ultimately organs were recovered from 3 of these donors.


Assuntos
Dissidências e Disputas , Seleção do Doador/organização & administração , Família/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Doadores de Tecidos/psicologia , Obtenção de Tecidos e Órgãos/organização & administração , Adolescente , Adulto , Feminino , Humanos , Intenção , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estados Unidos , United States Health Resources and Services Administration
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