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1.
Cell ; 150(2): 264-78, 2012 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-22817890

RESUMEN

Most mutations in cancer genomes are thought to be acquired after the initiating event, which may cause genomic instability and drive clonal evolution. However, for acute myeloid leukemia (AML), normal karyotypes are common, and genomic instability is unusual. To better understand clonal evolution in AML, we sequenced the genomes of M3-AML samples with a known initiating event (PML-RARA) versus the genomes of normal karyotype M1-AML samples and the exomes of hematopoietic stem/progenitor cells (HSPCs) from healthy people. Collectively, the data suggest that most of the mutations found in AML genomes are actually random events that occurred in HSPCs before they acquired the initiating mutation; the mutational history of that cell is "captured" as the clone expands. In many cases, only one or two additional, cooperating mutations are needed to generate the malignant founding clone. Cells from the founding clone can acquire additional cooperating mutations, yielding subclones that can contribute to disease progression and/or relapse.


Asunto(s)
Evolución Clonal , Leucemia Mieloide Aguda/genética , Mutación , Adulto , Anciano , Análisis Mutacional de ADN , Progresión de la Enfermedad , Femenino , Estudio de Asociación del Genoma Completo , Células Madre Hematopoyéticas/metabolismo , Humanos , Leucemia Mieloide Aguda/fisiopatología , Masculino , Persona de Mediana Edad , Proteínas de Fusión Oncogénica/genética , Recurrencia , Piel/metabolismo , Adulto Joven
2.
Ann Fam Med ; 22(3): 223-229, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38806258

RESUMEN

PURPOSE: Continuity of care is broadly associated with better patient health outcomes. The relative contributions of continuity with an individual physician and with a practice, however, have not generally been distinguished. This retrospective observational study examined the impact of continuity of care for patients seen at their main clinic but by different family physicians. METHODS: We analyzed linked health administrative data from 2015-2018 from Alberta, Canada to explore the association of physician and clinic continuity with rates of emergency department (ED) visits and hospitalizations across varying levels of patient complexity. Physician continuity was calculated using the known provider of care index and clinic continuity with an analogous measure. We developed zero-inflated negative binomial models to assess the association of each with all-cause ED visits and hospitalizations. RESULTS: High physician continuity was associated with lower ED use across all levels of patient complexity and with fewer hospitalizations for highly complex patients. Broadly, no (0%) clinic continuity was associated with increased use and complete (100%) clinic continuity with decreased use, with the largest effect seen for the most complex patients. Levels of clinic continuity between 1% and 50% were generally associated with slightly higher use, and levels of 51% to 99% with slightly lower use. CONCLUSIONS: The best health care outcomes (measured by ED visits and hospitalizations) are associated with consistently seeing one's own primary family physician or seeing a clinic partner when that physician is unavailable. The effect of partial clinic continuity appears complex and requires additional research. These results provide some reassurance for part-time and shared practices, and guidance for primary care workforce policy makers.


Asunto(s)
Continuidad de la Atención al Paciente , Servicio de Urgencia en Hospital , Hospitalización , Atención Primaria de Salud , Humanos , Alberta , Estudios Retrospectivos , Continuidad de la Atención al Paciente/estadística & datos numéricos , Femenino , Masculino , Atención Primaria de Salud/estadística & datos numéricos , Persona de Mediana Edad , Servicio de Urgencia en Hospital/estadística & datos numéricos , Adulto , Hospitalización/estadística & datos numéricos , Anciano , Médicos de Familia/estadística & datos numéricos , Adulto Joven , Adolescente , Instituciones de Atención Ambulatoria/estadística & datos numéricos
4.
J Hand Ther ; 36(3): 641-646, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36914495

RESUMEN

STUDY DESIGN: Clinical measurement INTRODUCTION: Dexterity is important for daily activities. The Corbett Targeted Coin Test (CTCT) measures dexterity with palm-to-finger translation and proprioceptive target placement, but lacks established norms. PURPOSE OF THE STUDY: To establish norms for the CTCT with healthy adult subjects. METHODS: The inclusion criteria consisted of participants that were community dwelling, non-institutionalized, able to make a fist with both hands, perform finger-to-palm translation of twenty coins, and be at least 18 years of age. CTCT standardized testing procedures were followed. Quality of performance (QoP) scores were determined by speed in seconds and number of coin drops (each a 5-second penalty). QoP was summarized within each age, gender and hand dominance subgroup using the mean, median, minimum, and maximum. Correlation coefficients were computed for relationships between age and QoP, and between handspan and QoP. RESULTS: Of the 207 individuals who participated, 131 were females and 76 males with an age range of 18-86 and mean age of 37.16. Individual QoP scores ranged from 13.8 to 105.3 seconds, with median scores ranging from 28.7 to 53.3 seconds. The mean for males was 37.5 seconds for the dominant hand (range 15.7-105.3) and 42.3 seconds (range 17.9.-86.8) for the non-dominant hand. The mean for females was 34.7 seconds for the dominant hand (range 14.8-67.0) and 38.6 seconds (range 13.8.-82.7) for the non-dominant hand. Lower QoP scores indicate a faster and/or more accurate dexterity performance. Females showed better median QoP for most age groups. The best median QoP scores were seen in the 30-39 and 40-49 age ranges. DISCUSSION: Our study agrees to some extent with other research that reported dexterity decreases with age, and increases with smaller hand spans. CONCLUSION: Normative data for the CTCT can be a guide for clinicians evaluating and monitoring patient dexterity with palm-to-finger translation and proprioceptive target placement.

5.
Small Bus Econ (Dordr) ; 58(2): 843-865, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-38624815

RESUMEN

Abstract: We assess the role of race in loans made through the Paycheck Protection Program (PPP). The PPP program, created by the U.S. government as a response to the Covid-19 pandemic, provides loans to small businesses so they can keep employees on their payroll. We argue that the historical record and PPP program design choices made it likely that many Black-owned businesses received smaller PPP loans than White-owned businesses. Using newly released data on the PPP program, we find that Black-owned businesses received loans that were approximately 50% lower than observationally similar White-owned businesses. The effect is marginally smaller in areas with more bank competition and disappeared over time as changes to the PPP program were implemented allowing for entry by fintechs and other non-traditional lenders. Plain English Summary: We find that Black-owned businesses received loans through the Paycheck Protection Program that were approximately 50 percent lower than White-owned businesses with similar characteristics. However, this difference in loan size shrank over time as more non-bank lenders such as fintechs were allowed to participate in the program and began approving PPP loans. Loan size differences were also slightly smaller in zip codes containing a larger number of bank branches. These results are consistent with prior research which shows lending discrimination by commercial banks against Black borrowers. It is also consistent with studies showing that greater access to and competition among banks and other lenders can reduce discrimination. In light of these results we recommend that policy makers account for existing racial inequalities within banking or other systems in their program design to produce more equitable outcomes.

6.
Br J Haematol ; 193(5): 951-960, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33993466

RESUMEN

Umbilical cord blood (UCB) transplantation is a potentially curative treatment for patients with refractory severe aplastic anaemia (SAA), but has historically been associated with delayed engraftment and high graft failure and mortality rates. We conducted a prospective phase 2 trial to assess outcome of an allogeneic transplant regimen that co-infused a single UCB unit with CD34+ -selected cells from a haploidentical relative. Among 29 SAA patients [including 10 evolved to myelodysplastic syndrome (MDS)] who underwent the haplo cord transplantation (median age 20 years), 97% had neutrophil recovery (median 10 days), and 93% had platelet recovery (median 32 days). Early myeloid engraftment was from the haplo donor and was gradually replaced by durable engraftment from UCB in most patients. The cumulative incidences of grade II-IV acute and chronic graft-versus-host disease (GVHD) were 21% and 41%, respectively. With a median follow-up of 7·5 years, overall survival was 83% and GVHD/relapse-free survival was 69%. Patient- and transplant-related factors had no impact on engraftment and survival although transplants with haplo-versus-cord killer-cell immunoglobulin-like receptor (KIR) ligand incompatibility had delayed cord engraftment. Our study shows haplo cord transplantation is associated with excellent engraftment and long-term outcome, providing an alternative option for patients with refractory SAA and hypoplastic MDS who lack human leucocyte antigen (HLA)-matched donors.


Asunto(s)
Anemia Aplásica , Trasplante de Células Madre de Sangre del Cordón Umbilical , Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Síndromes Mielodisplásicos , Adolescente , Adulto , Anemia Aplásica/sangre , Anemia Aplásica/mortalidad , Anemia Aplásica/terapia , Niño , Preescolar , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Enfermedad Injerto contra Huésped/sangre , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/mortalidad , Humanos , Incidencia , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/sangre , Síndromes Mielodisplásicos/mortalidad , Síndromes Mielodisplásicos/terapia , Recuento de Plaquetas , Estudios Prospectivos , Tasa de Supervivencia , Trasplante Haploidéntico
7.
Diabetes Spectr ; 34(3): 283-291, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34511855

RESUMEN

AIM: To measure cost and length of stay in patients with and without a diagnosis of diabetes admitted with cardiovascular, pulmonary, or cerebrovascular disease. METHODS: Retrospective study used International Classification of Diseases, 10th Revision, Clinical Modification codes to identify patients with diabetes, cardiovascular, pulmonary, or cerebrovascular disease. The All Patients Refined Diagnosis Related Groups, which classify patients according to admission diagnosis, severity of illness, and risk of mortality, was used to determine actual (discharge) diagnoses. Total admission cost and length of stay were compared using the Wilcoxon rank-sum test. RESULTS: Study reviewed 48,572 subjects who met inclusion criteria. When compared with patients without diabetes of similar age, sex, race, risk of mortality, and severity of illness and controlling for length of stay, individuals with diabetes had similar total admission costs. Lengths of stay were similar for individuals with and without diabetes admitted with a diagnosis of cerebrovascular disease or respiratory infection. However, patients with a primary diagnosis of congestive heart failure and a secondary diagnosis of diabetes incurred longer lengths of stay. CONCLUSION: Individuals with diabetes and congestive heart failure have longer lengths of stay than those without diabetes. To decrease the economic burden of diabetes and chronic conditions, primary care providers and hospitals need to implement guidelines regarding the management of care for individuals with two or more chronic conditions.

8.
Br J Haematol ; 189(3): 551-558, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32086819

RESUMEN

Heavily transfused patients frequently develop human leukocyte antigen (HLA) allo-immunization resulting in platelet transfusion refractoriness and a high risk for life-threatening thrombocytopenia. Data suggest complement activation leading to the destruction of platelets bound by HLA allo-antibodies may play a pathophysiologic role in platelet refractoriness. Here we conducted a pilot trial to investigate the use of eculizumab, a monoclonal antibody that binds and inhibits C5 complement, to treat platelet transfusion refractoriness in allo-immunized patients with severe thrombocytopenia. A single eculizumab infusion was administered to 10 eligible patients, with four (40%) patients overcoming platelet refractories assessed measuring the corrected platelet count increment (CCI) 10-60 min and 18-24 h post transfusion. Responding patients had a reduction in the requirement for subsequent platelet transfusions and had higher post-transfusion platelet increments for 14 days following eculizumab administration. Remarkably, three of the four responders met CCI criteria for response despite receiving HLA-incompatible platelets. Our results suggest that eculizumab has the ability to overcome platelet transfusion refractoriness in patients with broad HLA allo-immunization. This study establishes proof of principle that complement inhibition can treat platelet transfusion refractoriness, laying the foundation for a large multicentre trial to assess the overall efficacy of this approach (ClinicalTrials.gov, identifier: NCT02298933).


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Antígenos HLA/inmunología , Inmunización/métodos , Transfusión de Plaquetas/métodos , Adolescente , Adulto , Anciano , Anticuerpos Monoclonales Humanizados/farmacología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Adulto Joven
9.
Transfus Apher Sci ; 59(6): 102922, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32883593

RESUMEN

SARS-CoV-2 has infected millions worldwide. The virus is novel, and currently there is no approved treatment. Convalescent plasma may offer a treatment option. We evaluated trends of IgM/IgG antibodies/plasma viral load in donors and recipients of convalescent plasma. 114/139 (82 %) donors had positive IgG antibodies. 46/114 donors tested positive a second time by NP swab. Among those retested, the median IgG declined (p < 0.01) between tests. 25/139 donors with confirmed SARS-CoV-2 were negative for IgG antibodies. This suggests that having had the infection does not necessarily convey immunity, or there is a short duration of immunity associated with a decline in antibodies. Plasma viral load obtained on 35/39 plasma recipients showed 22 (62.9 %) had non-detectable levels on average 14.5 days from positive test versus 6.2 days in those with detectable levels (p < 0.01). There was a relationship between IgG and viral load. IgG was higher in those with non-detectable viral loads. There was no relationship between viral load and blood type (p = 0.87) or death (0.80). Recipients with detectable viral load had lower IgG levels; there was no relationship between viral load, blood type or death.


Asunto(s)
Anticuerpos Antivirales/administración & dosificación , COVID-19/sangre , COVID-19/terapia , SARS-CoV-2 , Adulto , Anciano , Femenino , Humanos , Inmunización Pasiva , Inmunoglobulina G/administración & dosificación , Inmunoglobulina M/administración & dosificación , Masculino , Persona de Mediana Edad , Sueroterapia para COVID-19
10.
Healthc Q ; 22(3): 40-46, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31845857

RESUMEN

Attachment to a primary care physician (PCP) is a foundational component of the Patient's Medical Home. Yet how can attachment exist in a system that does not limit where patients seek care? This article describes a top-down approach with the ideologies of a bottom-up collaborative to address attachment within an Alberta primary care network. The steps taken to reduce the number of patients listed on multiple PCP panels from 27% to 4% will be described. Learnings from this initiative suggest that direct involvement with providers, coupled with engaged physician leadership, can create a local system of information delivery that supports the attachment of patients to their most responsible PCP.


Asunto(s)
Atención Dirigida al Paciente , Relaciones Médico-Paciente , Médicos de Atención Primaria/estadística & datos numéricos , Alberta , Humanos , Prioridad del Paciente , Atención Primaria de Salud/estadística & datos numéricos
11.
Nature ; 481(7382): 506-10, 2012 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-22237025

RESUMEN

Most patients with acute myeloid leukaemia (AML) die from progressive disease after relapse, which is associated with clonal evolution at the cytogenetic level. To determine the mutational spectrum associated with relapse, we sequenced the primary tumour and relapse genomes from eight AML patients, and validated hundreds of somatic mutations using deep sequencing; this allowed us to define clonality and clonal evolution patterns precisely at relapse. In addition to discovering novel, recurrently mutated genes (for example, WAC, SMC3, DIS3, DDX41 and DAXX) in AML, we also found two major clonal evolution patterns during AML relapse: (1) the founding clone in the primary tumour gained mutations and evolved into the relapse clone, or (2) a subclone of the founding clone survived initial therapy, gained additional mutations and expanded at relapse. In all cases, chemotherapy failed to eradicate the founding clone. The comparison of relapse-specific versus primary tumour mutations in all eight cases revealed an increase in transversions, probably due to DNA damage caused by cytotoxic chemotherapy. These data demonstrate that AML relapse is associated with the addition of new mutations and clonal evolution, which is shaped, in part, by the chemotherapy that the patients receive to establish and maintain remissions.


Asunto(s)
Evolución Clonal/genética , Genoma Humano/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Células Clonales/efectos de los fármacos , Células Clonales/metabolismo , Células Clonales/patología , Daño del ADN/efectos de los fármacos , Análisis Mutacional de ADN , Genes Relacionados con las Neoplasias/genética , Genoma Humano/efectos de los fármacos , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Mutagénesis/efectos de los fármacos , Mutagénesis/genética , Recurrencia , Reproducibilidad de los Resultados
13.
Br J Haematol ; 176(6): 950-960, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28169418

RESUMEN

Allogeneic haematopoietic stem cell transplantation is curative for severe aplastic anaemia (SAA) unresponsive to immunosuppressive therapy. To reduce chronic graft-versus-host disease (GVHD), which occurs more frequently after peripheral blood stem cell (PBSC) transplantation compared to bone-marrow transplantation (BMT), and to prevent graft rejection, we developed a novel partial T-cell depleted transplant that infuses high numbers of granulocyte colony-stimulating factor-mobilized CD34+ selected PBSCs combined with a BMT-equivalent dose of non-mobilized donor T-cells. Fifteen patients with refractory SAA received cyclophosphamide, anti-thymocyte globulin and fludarabine conditioning, and were transplanted with a median 8 × 106 CD34+  cells/kg and 2 × 107 non-mobilized CD3+ T-cells/kg from human leucocyte antigen-matched sibling donors. All achieved sustained engraftment with only two developing acute and two developing chronic GVHD. With a 3·5-year median follow-up, 86% of patients survived and were transfusion-independent. When compared to a retrospective cohort of 56 bone-marrow failure patients that received the identical transplant preparative regimen and GVHD prophylaxis with the exception that the allograft contained unmanipulated PBSCs, partial T-cell depleted transplant recipients had delayed donor T-cell chimerism and relative reduction of 75% in the incidence of acute grade II-IV GVHD (13% vs. 52%; P = 0·010) and of 82% in chronic GVHD (13% vs. 72%; P = 0·0004). In multivariate analysis, partial T-cell depleted transplants remained significantly associated with a reduced risk of GVHD. In conclusion, for patients with refractory SAA, this novel transplant strategy achieves excellent engraftment and survival when compared to unmanipulated PBSC transplants and dramatically reduces the incidence of both acute and chronic GVHD.


Asunto(s)
Anemia Aplásica/diagnóstico , Anemia Aplásica/terapia , Trasplante de Células Madre de Sangre Periférica , Células Madre de Sangre Periférica/metabolismo , Linfocitos T/trasplante , Adolescente , Adulto , Anciano , Antígenos CD34/metabolismo , Biomarcadores , Niño , Estudios de Cohortes , Terapia Combinada , Femenino , Supervivencia de Injerto , Enfermedad Injerto contra Huésped/etiología , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Linfocitos T/metabolismo , Quimera por Trasplante , Trasplante Homólogo , Resultado del Tratamiento , Adulto Joven
14.
Haematologica ; 102(3): 600-609, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27846612

RESUMEN

Hematopoietic stem cells can be mobilized from healthy donors using single-agent plerixafor without granulocyte colony-stimulating factor and, following allogeneic transplantation, can result in sustained donor-derived hematopoiesis. However, when a single dose of plerixafor is administered at a conventional 240 µg/kg dose, approximately one-third of donors will fail to mobilize the minimally acceptable dose of CD34+ cells needed for allogeneic transplantation. We conducted an open-label, randomized trial to assess the safety and activity of high-dose (480 µg/kg) plerixafor in CD34+ cell mobilization in healthy donors. Subjects were randomly assigned to receive either a high dose or a conventional dose (240 µg/kg) of plerixafor, given as a single subcutaneous injection, in a two-sequence, two-period, crossover design. Each treatment period was separated by a 2-week minimum washout period. The primary endpoint was the peak CD34+ count in the blood, with secondary endpoints of CD34+ cell area under the curve (AUC), CD34+ count at 24 hours, and time to peak CD34+ following the administration of plerixafor. We randomized 23 subjects to the two treatment sequences and 20 subjects received both doses of plerixafor. Peak CD34+ count in the blood was significantly increased (mean 32.2 versus 27.8 cells/µL, P=0.0009) and CD34+ cell AUC over 24 hours was significantly increased (mean 553 versus 446 h cells/µL, P<0.0001) following the administration of the 480 µg/kg dose of plerixafor compared with the 240 µg/kg dose. Remarkably, of seven subjects who mobilized poorly (peak CD34+ ≤20 cells/µL) after the 240 µg/kg dose of plerixafor, six achieved higher peak CD34+ cell numbers and all achieved higher CD34+ AUC over 24 hours after the 480 µg/kg dose. No grade 3 or worse drug-related adverse events were observed. This study establishes that high-dose plerixafor can be safely administered in healthy donors and mobilizes greater numbers of CD34+ cells than conventional-dose plerixafor, which may improve CD34+ graft yields and reduce the number of apheresis procedures needed to collect sufficient stem cells for allogeneic transplantation. (ClinicalTrials.gov, identifier: NCT00322127).


Asunto(s)
Antígenos CD34/metabolismo , Movilización de Célula Madre Hematopoyética , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/metabolismo , Compuestos Heterocíclicos/administración & dosificación , Donantes de Tejidos , Adulto , Bencilaminas , Ensayo de Unidades Formadoras de Colonias , Estudios Cruzados , Ciclamas , Femenino , Voluntarios Sanos , Movilización de Célula Madre Hematopoyética/métodos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Trasplante de Células Madre Hematopoyéticas/métodos , Células Madre Hematopoyéticas/citología , Humanos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Adulto Joven
15.
Epilepsy Behav ; 72: 89-98, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28575774

RESUMEN

We conducted an exploratory RCT to examine feasibility and preliminary efficacy for a manual-based psychosocial group intervention aimed at improving epilepsy knowledge, self-management skills, and quality of life in young people with epilepsy. METHOD: Eighty-three participants (33:50m/f; age range 12-17years) were randomized to either the treatment or control group in seven tertiary paediatric neuroscience centres in the UK, using a wait-list control design. Participants were excluded if they reported suicidal ideation and/or scored above the cut off on mental health screening measures, or if they had a learning disability or other neurological disorder. The intervention consisted of six weekly 2-hour sessions using guided discussion, group exercises and role-plays facilitated by an epilepsy nurse and a clinical psychologist. RESULTS: At three month follow up the treatment group (n=40) was compared with a wait-list control group (n=43) on a range of standardized measures. There was a significant increase in epilepsy knowledge in the treatment group (p=0.02). Participants receiving the intervention were also significantly more confident in speaking to others about their epilepsy (p=0.04). Quality of life measures did not show significant change. Participants reported the greatest value of attending the group was: Learning about their epilepsy (46%); Learning to cope with difficult feelings (29%); and Meeting others with epilepsy (22%). Caregiver and facilitator feedback was positive, and 92% of participants would recommend the group to others. CONCLUSION: This brief psychosocial group intervention was effective in increasing participants' knowledge of epilepsy and improved confidence in discussing their epilepsy with others. We discuss the qualitative feedback, feasibility, strengths and limitations of the PIE trial.


Asunto(s)
Adaptación Psicológica , Epilepsia/psicología , Epilepsia/terapia , Sistemas de Apoyo Psicosocial , Psicoterapia de Grupo/métodos , Autocuidado/psicología , Adolescente , Cuidadores/psicología , Niño , Epilepsia/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Aprendizaje , Masculino , Calidad de Vida/psicología , Autocuidado/métodos
16.
Nature ; 469(7331): 529-33, 2011 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-21270892

RESUMEN

'Orang-utan' is derived from a Malay term meaning 'man of the forest' and aptly describes the southeast Asian great apes native to Sumatra and Borneo. The orang-utan species, Pongo abelii (Sumatran) and Pongo pygmaeus (Bornean), are the most phylogenetically distant great apes from humans, thereby providing an informative perspective on hominid evolution. Here we present a Sumatran orang-utan draft genome assembly and short read sequence data from five Sumatran and five Bornean orang-utan genomes. Our analyses reveal that, compared to other primates, the orang-utan genome has many unique features. Structural evolution of the orang-utan genome has proceeded much more slowly than other great apes, evidenced by fewer rearrangements, less segmental duplication, a lower rate of gene family turnover and surprisingly quiescent Alu repeats, which have played a major role in restructuring other primate genomes. We also describe a primate polymorphic neocentromere, found in both Pongo species, emphasizing the gradual evolution of orang-utan genome structure. Orang-utans have extremely low energy usage for a eutherian mammal, far lower than their hominid relatives. Adding their genome to the repertoire of sequenced primates illuminates new signals of positive selection in several pathways including glycolipid metabolism. From the population perspective, both Pongo species are deeply diverse; however, Sumatran individuals possess greater diversity than their Bornean counterparts, and more species-specific variation. Our estimate of Bornean/Sumatran speciation time, 400,000 years ago, is more recent than most previous studies and underscores the complexity of the orang-utan speciation process. Despite a smaller modern census population size, the Sumatran effective population size (N(e)) expanded exponentially relative to the ancestral N(e) after the split, while Bornean N(e) declined over the same period. Overall, the resources and analyses presented here offer new opportunities in evolutionary genomics, insights into hominid biology, and an extensive database of variation for conservation efforts.


Asunto(s)
Variación Genética , Genoma/genética , Pongo abelii/genética , Pongo pygmaeus/genética , Animales , Centrómero/genética , Cerebrósidos/metabolismo , Cromosomas , Evolución Molecular , Femenino , Reordenamiento Génico/genética , Especiación Genética , Genética de Población , Humanos , Masculino , Filogenia , Densidad de Población , Dinámica Poblacional , Especificidad de la Especie
17.
Nature ; 464(7291): 999-1005, 2010 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-20393555

RESUMEN

Massively parallel DNA sequencing technologies provide an unprecedented ability to screen entire genomes for genetic changes associated with tumour progression. Here we describe the genomic analyses of four DNA samples from an African-American patient with basal-like breast cancer: peripheral blood, the primary tumour, a brain metastasis and a xenograft derived from the primary tumour. The metastasis contained two de novo mutations and a large deletion not present in the primary tumour, and was significantly enriched for 20 shared mutations. The xenograft retained all primary tumour mutations and displayed a mutation enrichment pattern that resembled the metastasis. Two overlapping large deletions, encompassing CTNNA1, were present in all three tumour samples. The differential mutation frequencies and structural variation patterns in metastasis and xenograft compared with the primary tumour indicate that secondary tumours may arise from a minority of cells within the primary tumour.


Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundario , Neoplasias de la Mama/genética , Genoma Humano/genética , Mutación/genética , Trasplante de Neoplasias , Adulto , Neoplasias de la Mama/patología , Variaciones en el Número de Copia de ADN/genética , Análisis Mutacional de ADN , Progresión de la Enfermedad , Femenino , Frecuencia de los Genes/genética , Genómica , Humanos , Translocación Genética/genética , Trasplante Heterólogo , alfa Catenina/genética
18.
J Immunol ; 191(12): 6241-9, 2013 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-24244025

RESUMEN

Plerixafor (Mozobil) is a CXCR4 antagonist that rapidly mobilizes CD34(+) cells into circulation. Recently, plerixafor has been used as a single agent to mobilize peripheral blood stem cells for allogeneic hematopoietic cell transplantation. Although G-CSF mobilization is known to alter the phenotype and cytokine polarization of transplanted T cells, the effects of plerixafor mobilization on T cells have not been well characterized. In this study, we show that alterations in the T cell phenotype and cytokine gene expression profiles characteristic of G-CSF mobilization do not occur after mobilization with plerixafor. Compared with nonmobilized T cells, plerixafor-mobilized T cells had similar phenotype, mixed lymphocyte reactivity, and Foxp3 gene expression levels in CD4(+) T cells, and did not undergo a change in expression levels of 84 genes associated with Th1/Th2/Th3 pathways. In contrast with plerixafor, G-CSF mobilization decreased CD62L expression on both CD4 and CD8(+) T cells and altered expression levels of 16 cytokine-associated genes in CD3(+) T cells. To assess the clinical relevance of these findings, we explored a murine model of graft-versus-host disease in which transplant recipients received plerixafor or G-CSF mobilized allograft from MHC-matched, minor histocompatibility-mismatched donors; recipients of plerixafor mobilized peripheral blood stem cells had a significantly higher incidence of skin graft-versus-host disease compared with mice receiving G-CSF mobilized transplants (100 versus 50%, respectively, p = 0.02). These preclinical data show plerixafor, in contrast with G-CSF, does not alter the phenotype and cytokine polarization of T cells, which raises the possibility that T cell-mediated immune sequelae of allogeneic transplantation in humans may differ when donor allografts are mobilized with plerixafor compared with G-CSF.


Asunto(s)
Citocinas/genética , Regulación de la Expresión Génica/inmunología , Factor Estimulante de Colonias de Granulocitos/farmacología , Movilización de Célula Madre Hematopoyética , Compuestos Heterocíclicos/farmacología , Subgrupos de Linfocitos T/efectos de los fármacos , Animales , Antígenos CD/biosíntesis , Antígenos CD/genética , Bencilaminas , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/trasplante , Ciclamas , Citocinas/biosíntesis , Factores de Transcripción Forkhead/biosíntesis , Factores de Transcripción Forkhead/genética , Enfermedad Injerto contra Huésped/inmunología , Humanos , Inmunofenotipificación , Prueba de Cultivo Mixto de Linfocitos , Linfopoyesis , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Quimera por Radiación , Receptores CXCR4/efectos de los fármacos , Organismos Libres de Patógenos Específicos , Subgrupos de Linfocitos T/inmunología
19.
Biol Blood Marrow Transplant ; 20(9): 1435-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24844857

RESUMEN

Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by intravascular hemolysis, venous thrombosis, and bone marrow failure. Seventeen patients with debilitating PNH, including 8 who were HLA-alloimmunized, underwent a reduced-intensity allogeneic hematopoietic cell transplantation (HCT). All received cyclophosphamide/fludarabine +/- antithymocyte globulin followed by a granulocyte colony-stimulating factor-mobilized HCT from an HLA-matched relative. Glycosylphosphatidylinositol-negative neutrophils were detectable after engraftment but disappeared completely at a median 100 days after transplantation. With a median follow-up of nearly 6 years, 15 patients (87.8%) survived, all without any evidence of PNH, transfusion independent, and off anticoagulation. Allogeneic reduced-intensity HCT remains a curative therapeutic option for PNH patients who are not candidates for eculizumab treatment.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/métodos , Hemoglobinuria Paroxística/terapia , Acondicionamiento Pretrasplante/métodos , Vidarabina/análogos & derivados , Adulto , Femenino , Hemoglobinuria Paroxística/mortalidad , Humanos , Masculino , Análisis de Supervivencia , Resultado del Tratamiento , Vidarabina/administración & dosificación , Vidarabina/uso terapéutico , Adulto Joven
20.
Cytotherapy ; 16(7): 927-33, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24831837

RESUMEN

BACKGROUND AIMS: Although cytomegalovirus (CMV) infection after allogeneic stem cell transplantation (SCT) is rarely fatal, the management of CMV by pre-emptive medication for viral reactivation has toxicity and carries a financial burden. New strategies to prevent CMV reactivation with vaccines and antiviral T cells may represent an advance over pre-emptive strategies but have yet to be justified in terms of transplantation outcome and cost. METHODS: We compared outcomes and post-transplantation treatment cost in 44 patients who never required pre-emptive CMV treatment with 90 treated patients undergoing SCT at our institute between 2006 and 2012. Eighty-one subjects received CD34+ selected myeloablative SCT, 12 umbilical cord blood transplants, and 41 T-replete non-myeloablative SCT. One hundred nineteen patients (89%) were at risk for CMV because either the donor or recipient was seropositive. Of these, 90 patients (75.6%) reactivated CMV at a median of 30 (range 8-105) days after transplantation and received antivirals. RESULTS: There was no difference in standard transplantation risk factors between the two groups. In multivariate modeling, CMV reactivation >250 copies/mL (odds ratio = 3, P < 0.048), total duration of inpatient IV antiviral therapy (odds ratio = 1.04, P < 0.001), type of transplantation (T-deplete vs. T-replete; odds ratio = 4.65, P < 0.017) were found to be significantly associated with increased non-relapse mortality. The treated group incurred an additional cost of antiviral medication and longer hospitalization within the first 6 months after SCT of $58,000 to $74,000 per patient. CONCLUSIONS: Our findings suggest that to prevent CMV reactivation, treatment should be given within 1 week of SCT. Preventative treatment may improve outcome and have significant cost savings.


Asunto(s)
Infecciones por Citomegalovirus/patología , Citomegalovirus/genética , Neoplasias Hematológicas/terapia , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Trasplante Homólogo/efectos adversos , Adolescente , Adulto , Anciano , Niño , Costo de Enfermedad , Citomegalovirus/patogenicidad , Infecciones por Citomegalovirus/economía , Infecciones por Citomegalovirus/virología , Femenino , Neoplasias Hematológicas/mortalidad , Neoplasias Hematológicas/patología , Trasplante de Células Madre Hematopoyéticas/economía , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Linfocitos T/inmunología , Linfocitos T/patología , Linfocitos T/virología , Donantes de Tejidos , Trasplante Homólogo/economía , Activación Viral/genética
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