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2.
Mol Biol Evol ; 38(8): 3202-3219, 2021 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-33822137

RESUMEN

Evolutionary dynamics at the population level play a central role in creating the diversity of life on our planet. In this study, we sought to understand the origins of such population-level variation in mating systems and defensive acylsugar chemistry in Solanum habrochaites-a wild tomato species found in diverse Andean habitats in Ecuador and Peru. Using Restriction-site-Associated-DNA-Sequencing (RAD-seq) of 50 S. habrochaites accessions, we identified eight population clusters generated via isolation and hybridization dynamics of 4-6 ancestral populations. Detailed characterization of mating systems of these clusters revealed emergence of multiple self-compatible (SC) groups from progenitor self-incompatible populations in the northern part of the species range. Emergence of these SC groups was also associated with fixation of deleterious alleles inactivating acylsugar acetylation. The Amotape-Huancabamba Zone-a geographical landmark in the Andes with high endemism and isolated microhabitats-was identified as a major driver of differentiation in the northern species range, whereas large geographical distances contributed to population structure and evolution of a novel SC group in the central and southern parts of the range, where the species was also inferred to have originated. Findings presented here highlight the role of the diverse ecogeography of Peru and Ecuador in generating population differentiation, and enhance our understanding of the microevolutionary processes that create biological diversity.


Asunto(s)
Flujo Génico , Autoincompatibilidad en las Plantas con Flores/genética , Solanum lycopersicum/genética , Solanum/genética , Acetilación , Ecuador , Solanum lycopersicum/metabolismo , Perú , Filogeografía , Autofecundación , Solanum/metabolismo
3.
Mil Med ; 184(7-8): e301-e308, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-30690462

RESUMEN

INTRODUCTION: Access to high-quality healthcare, including mental healthcare, is a high priority for the Department of Veterans Affairs (VA). Meaningful monitoring of progress will require patient-centered measures of access. To that end, we developed the Perceived Access Inventory focused on access to VA mental health services (PAI-VA). However, VA is purchasing increasing amounts of mental health services from community mental health providers. In this paper, we describe the development of a PAI for users of VA-funded community mental healthcare that incorporates access barriers unique to community care service use and compares the barriers most frequently reported by veterans using community mental health services to those most frequently reported by veterans using VA mental health services. MATERIALS AND METHODS: We conducted mixed qualitative and quantitative interviews with 25 veterans who had experience using community mental health services through the Veterans Choice Program (VCP). We used opt-out invitation letters to recruit veterans from three geographic regions. Data were collected on sociodemographics, rurality, symptom severity, and service satisfaction. Participants also completed two measures of perceived barriers to mental healthcare: the PAI-VA adapted to focus on access to mental healthcare in the community and Hoge's 13-item measure. This study was reviewed and approved by the VA Central Institutional Review Board. RESULTS: Analysis of qualitative interview data identified four topics that were not addressed in the PAI-VA: veterans being billed directly by a VCP mental health provider, lack of care coordination and communication between VCP and VA mental health providers, veterans needing to travel to a VA facility to have VCP provider prescriptions filled, and delays in VCP re-authorization. To develop a PAI for community-care users, we created items corresponding to each of the four community-care-specific topics and added them to the 43-item PAI-VA. When we compared the 10 most frequently endorsed barriers to mental healthcare in this study sample to the ten most frequently endorsed by a separate sample of current VA mental healthcare users, six items were common to both groups. The four items unique to community-care were: long waits for the first mental health appointment, lack of awareness of available mental health services, short appointments, and providers' lack of knowledge of military culture. CONCLUSIONS: Four new barriers specific to veteran access to community mental healthcare were identified. These barriers, which were largely administrative rather than arising from the clinical encounter itself, were included in the PAI for community care. Study strengths include capturing access barriers from the veteran experience across three geographic regions. Weaknesses include the relatively small number of participants and data collection from an early stage of Veteran Choice Program implementation. As VA expands its coverage of community-based mental healthcare, being able to assess the success of the initiative from the perspective of program users becomes increasingly important. The 47-item PAI for community care offers a useful tool to identify barriers experienced by veterans in accessing mental healthcare in the community, overall and in specific settings, as well as to track the impact of interventions to improve access to mental healthcare.


Asunto(s)
Servicios de Salud Mental/clasificación , Percepción , Veteranos/psicología , Adulto , Anciano , Servicios de Salud Comunitaria/clasificación , Servicios de Salud Comunitaria/métodos , Femenino , Accesibilidad a los Servicios de Salud/normas , Accesibilidad a los Servicios de Salud/estadística & datos numéricos , Humanos , Entrevistas como Asunto/métodos , Masculino , Servicios de Salud Mental/tendencias , Persona de Mediana Edad , Investigación Cualitativa , Estados Unidos , United States Department of Veterans Affairs/organización & administración , United States Department of Veterans Affairs/estadística & datos numéricos , Veteranos/estadística & datos numéricos
6.
Genome Biol Evol ; 9(2): 323-336, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-28164243

RESUMEN

Understanding mechanisms of coevolution between nuclear and mitochondrial (mt) genomes is a defining challenge in eukaryotic genetics. The angiosperm genus Silene is a natural system to investigate the causes and consequences of mt mutation rate variation because closely related species have highly divergent rates. In Silene species with fast-evolving mtDNA, nuclear genes that encode mitochondrially targeted proteins (N-mt genes) are also fast-evolving. This correlation could indicate positive selection to compensate for mt mutations, but might also result from a recent relaxation of selection. To differentiate between these interpretations, we used phylogenetic and population-genetic methods to test for positive and relaxed selection in three classes of N-mt genes (oxidative phosphorylation genes, ribosomal genes, and "RRR" genes involved in mtDNA recombination, replication, and repair). In all three classes, we found that species with fast-evolving mtDNA had: 1) elevated dN/dS, 2) an excess of nonsynonymous divergence relative to levels of intraspecific polymorphism, which is a signature of positive selection, and 3) no clear signals of relaxed selection. "Control" genes exhibited comparatively few signs of positive selection. These results suggest that high mt mutation rates can create selection on N-mt genes and that relaxed selection is an unlikely cause of recent accelerations in the evolution of N-mt genes. Because mt-RRR genes were found to be under positive selection, it is unlikely that elevated mt mutation rates in Silene were caused by inactivation of these mt-RRR genes. Therefore, the causes of extreme increases in angiosperm mt mutation rates remain uncertain.


Asunto(s)
ADN Mitocondrial/genética , Evolución Molecular , Silene/genética , Genes de Plantas , Selección Genética
7.
Urology ; 86(2): 300-5, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26199171

RESUMEN

OBJECTIVE: To examine relative contributions of functional parenchymal preservation and renal ischemia following nephron-sparing surgery (NSS). While residual functional parenchymal volume (FPV) is proposed as the key factor in predicting functional outcomes following NSS, efforts to curtail ischemia time continue to add technical complexity to partial nephrectomy. METHODS: Our kidney cancer database was queried for patients who underwent NSS with warm ischemia time (WIT). Patients with cross-sectional imaging for FPV calculation were included. Cylindrical volume approximation methodology was used to calculate FPV, accounting for the volume of tumor's endophytic component. Percent estimated glomerular filtration rate (eGFR) preservation, perioperatively and at 6 months, was the outcome metric. Spearman correlation and linear regression analyses were used to evaluate associations of WIT and %FPV preservation with renal function preservation. RESULTS: Of the 179 patients included, median preoperative eGFR was 88.4 (9.5% chronic kidney disease III or IV), tumor size was 2.7 cm (interquartile range [IQR] 2.0-3.6 cm), and R.E.N.A.L. nephrometry was low in 34%, intermediate in 57%, and high in 9%. Median WIT was 30 minutes (IQR 24-36), resulting in 97.4% FPV preservation. Median postoperative eGFR at 6.4 months was 80.5 (19.1% chronic kidney disease III or IV), a median of 93.1% eGFR preservation (IQR 85.1-101.7). At discharge, WIT (P <.001), not %FPV (P = .112), was associated with %eGFR preservation. However, 6 months following surgery, on multivariable analysis, both preoperative eGFR (linear regression coefficient = -0.208, P = .006) and %FPV preservation (linear regression coefficient = 0.491, P = .001), but not WIT (P = .946), demonstrated statistically significant association with %eGFR preservation. CONCLUSION: Residual FPV, and not WIT, appears to be the main predictor of ultimate renal function following NSS.


Asunto(s)
Neoplasias Renales/cirugía , Riñón/anatomía & histología , Riñón/fisiología , Nefrectomía/métodos , Isquemia Tibia , Anciano , Femenino , Humanos , Riñón/cirugía , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Pronóstico , Estudios Retrospectivos , Factores de Tiempo
8.
Lasers Surg Med ; 47(1): 1-5, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25559589

RESUMEN

BACKGROUND/OBJECTIVES: Despite precise surgical technique, some postoperative facial scars will depress and widen over time, likely due to weakened or inadequately replaced collagen fibers in the underlying dermis. The purpose of this study is to evaluate whether a 10,600 nm ablative carbon dioxide (CO2 ) fractional laser used early in the post-surgical setting results in improved postoperative facial scars after a single treatment session. STUDY DESIGN: A prospective randomized, comparative split-scar study was conducted on 20 subjects between the ages of 20-90. Subjects underwent Mohs surgery for nonmelanoma skin cancer of the face. Subsequent to tumor removal, subjects with a linear scar of 4 cm or greater were enrolled. On the day of suture removal, all subjects had one-half of their scar randomly selected and treated with a 10,600 nm CO2 fractional laser (energy = 10 mJ; density = 10%; spot size = 7 mm; pulse = 1). The untreated scar half served as a control. Scars were re-evaluated 12 weeks later. An independent blinded observer graded the scar halves with the Vancouver scar scale (VSS) immediately prior to treatment and 12 weeks after treatment. Subjects completed a visual analog scale (VAS) at the same time points. RESULTS: Three months after laser treatment, a significant decrease in VSS and 3 of the 4 of its individual parameters were detected in both control and treated halves of the scar. When comparing the laser group versus the control group, a statistically significant difference was not noted in VSS (P = 0.31) but a statistically significant difference in patient VAS was detected (P = 0.002). No side effects of the laser treatment were noted. CONCLUSION: Facial wounds sutured in a layered manner heal well. Patients prefer early fractional CO2 lasing of surgical scars, though use of the VSS failed to detect an objective difference between laser and control halves of scars. Conservative laser settings, a single session treatment, and VSS insensitivity for surgical scars may influence these findings.


Asunto(s)
Cicatriz/prevención & control , Láseres de Gas/uso terapéutico , Cirugía de Mohs , Cuidados Posoperatorios/métodos , Complicaciones Posoperatorias/prevención & control , Neoplasias Cutáneas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Cicatriz/etiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Método Simple Ciego , Resultado del Tratamiento , Escala Visual Analógica
9.
Science ; 346(6208): 466-9, 2014 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-25342802

RESUMEN

Study of human adaptation to extreme environments is important for understanding our cultural and genetic capacity for survival. The Pucuncho Basin in the southern Peruvian Andes contains the highest-altitude Pleistocene archaeological sites yet identified in the world, about 900 meters above confidently dated contemporary sites. The Pucuncho workshop site [4355 meters above sea level (masl)] includes two fishtail projectile points, which date to about 12.8 to 11.5 thousand years ago (ka). Cuncaicha rock shelter (4480 masl) has a robust, well-preserved, and well-dated occupation sequence spanning the past 12.4 thousand years (ky), with 21 dates older than 11.5 ka. Our results demonstrate that despite cold temperatures and low-oxygen conditions, hunter-gatherers colonized extreme high-altitude Andean environments in the Terminal Pleistocene, within about 2 ky of the initial entry of humans to South America.


Asunto(s)
Aclimatación , Altitud , Arqueología , Artefactos , Humanos , Perú
10.
Am J Dermatopathol ; 36(2): 186-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24394304

RESUMEN

The term "induction" has been used to describe epidermal changes overlying a dermatofibroma (DF). Follicular induction is most often associated with DF, but can be observed in other lesions, including focal mucinosis, nevus sebaceous, seborrheic keratosis, wart, neurofibroma, and scars. Dermatofibrosarcoma protuberans (DFSP) is a malignant fibrohistiocytic tumor that may be difficult to distinguish from DF. In contrast to DF, the epidermis overlying DFSP is usually attenuated or ulcerated. Here, we report a case of DFSP exhibiting follicular induction of the overlying epidermis. This epidermal change has been rarely reported in DFSP and may present a diagnostic pitfall in superficially sampled lesions.


Asunto(s)
Dermatofibrosarcoma/patología , Folículo Piloso/patología , Neoplasias Cutáneas/patología , Adolescente , Dermatofibrosarcoma/cirugía , Femenino , Humanos , Cirugía de Mohs , Neoplasias Cutáneas/cirugía
11.
Am J Dermatopathol ; 36(2): 174-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24061399

RESUMEN

Microcystic adnexal carcinoma (MAC) is an uncommon, locally aggressive, malignant cutaneous tumor with pilar and eccrine differentiation. Mohs micrographic surgery is the treatment of choice for this condition, but specific histological findings can complicate MAC removal and leave doubt as to whether the tumor has been completely removed. Here we describe the clinical and pathological characteristics of a case in which a patient with an MAC underwent multiple reexcisions because of the presence of benign subclinical syringomatous proliferations adjacent to the primary lesion. Our case raises awareness of syringomatous proliferation, a benign process histologically similar but behaviorally distinct from a primary MAC. This experience highlights the importance of continued communication between dermatopathologists and dermatologic surgeons in providing quality patient care.


Asunto(s)
Carcinoma de Apéndice Cutáneo/cirugía , Cirugía de Mohs , Neoplasias Primarias Secundarias/cirugía , Neoplasias de las Glándulas Sudoríparas/cirugía , Glándulas Sudoríparas/patología , Anciano , Carcinoma Basocelular/epidemiología , Carcinoma de Apéndice Cutáneo/patología , Carcinoma de Células Escamosas/epidemiología , Diagnóstico Diferencial , Femenino , Frente/patología , Humanos , Neoplasias Primarias Secundarias/patología , Neoplasias Cutáneas/epidemiología , Neoplasias de las Glándulas Sudoríparas/patología
12.
Clinics (Sao Paulo) ; 63(1): 59-66, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18297208

RESUMEN

PURPOSE: To establish a correlation between intrasac pressure measurements of a pressure sensor and an angiographic catheter placed in the same aneurysm sac before and after its exclusion by an endoprosthesis. METHODS: Patients who underwent endovascular abdominal aortic aneurysm repair and received an EndoSure wireless pressure sensor implant between March 19 and December 11, 2004 were enrolled in the study. Simultaneous readings of systolic, diastolic, mean, and pulse pressure within the aneurysm sac were obtained from the catheter and the sensor, both before and after sac exclusion by the endoprosthesis (Readings 1 and 2, respectively). Intrasac pressure measurements were compared using Pearson's correlation and Student's t test. Statistical significance was set at p<0.05. RESULTS: Twenty-five patients had the pressure sensor implanted, with simultaneous readings (i.e., recorded by both devices) obtained in 19 patients for Reading 1 and in 10 patients for Reading 2. There was a statistically significant correlation for all pressure variables during both readings, with p<0.01 for all except the pulse pressure in Reading 1 (p<0.05). Statistical significance of pressure variations before and after abdominal aortic aneurysm exclusion was coincident between the sensor and catheter for diastolic (p>0.05), mean (p>0.05), and pulse (p<0.01) pressures; the sole disagreement was observed for systolic pressure, which varied, on average, 31.23 mmHg by the catheter (p<0.05) and 22 mmHg (p>0.05) by the sensor. CONCLUSION: The excellent agreement between intrasac pressure readings recorded by the catheter and the sensor justifies use of the latter for detection of post-exclusion abdominal aortic aneurysm pressurization.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Determinación de la Presión Sanguínea/instrumentación , Implantación de Prótesis Vascular , Adulto , Anciano , Anciano de 80 o más Años , Angioplastia , Monitores de Presión Sanguínea , Femenino , Estudios de Seguimiento , Humanos , Cuidados Intraoperatorios , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Transductores de Presión
13.
Clinics ; Clinics;63(1): 59-66, 2008. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-474929

RESUMEN

PURPOSE: To establish a correlation between intrasac pressure measurements of a pressure sensor and an angiographic catheter placed in the same aneurysm sac before and after its exclusion by an endoprosthesis. METHODS: Patients who underwent endovascular abdominal aortic aneurysm repair and received an EndoSureTM wireless pressure sensor implant between March 19 and December 11, 2004 were enrolled in the study. Simultaneous readings of systolic, diastolic, mean, and pulse pressure within the aneurysm sac were obtained from the catheter and the sensor, both before and after sac exclusion by the endoprosthesis (Readings 1 and 2, respectively). Intrasac pressure measurements were compared using Pearson's correlation and Student's t test. Statistical significance was set at p<0.05. RESULTS: Twenty-five patients had the pressure sensor implanted, with simultaneous readings (i.e., recorded by both devices) obtained in 19 patients for Reading 1 and in 10 patients for Reading 2. There was a statistically significant correlation for all pressure variables during both readings, with p<0.01 for all except the pulse pressure in Reading 1 (p<0.05). Statistical significance of pressure variations before and after abdominal aortic aneurysm exclusion was coincident between the sensor and catheter for diastolic (p>0.05), mean (p>0.05), and pulse (p<0.01) pressures; the sole disagreement was observed for systolic pressure, which varied, on average, 31.23 mmHg by the catheter (p<0.05) and 22 mmHg (p>0.05) by the sensor. CONCLUSION: The excellent agreement between intrasac pressure readings recorded by the catheter and the sensor justifies use of the latter for detection of post-exclusion abdominal aortic aneurysm pressurization.


Asunto(s)
Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Aneurisma de la Aorta Abdominal/cirugía , Implantación de Prótesis Vascular , Determinación de la Presión Sanguínea/instrumentación , Angioplastia , Monitores de Presión Sanguínea , Estudios de Seguimiento , Cuidados Intraoperatorios , Reproducibilidad de los Resultados , Transductores de Presión
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