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1.
Proc Natl Acad Sci U S A ; 119(15): e2118879119, 2022 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-35377798

RESUMEN

Polyploidy results from whole-genome duplication and is a unique form of heritable variation with pronounced evolutionary implications. Different ploidy levels, or cytotypes, can exist within a single species, and such systems provide an opportunity to assess how ploidy variation alters phenotypic novelty, adaptability, and fitness, which can, in turn, drive the development of unique ecological niches that promote the coexistence of multiple cytotypes. Switchgrass, Panicum virgatum, is a widespread, perennial C4 grass in North America with multiple naturally occurring cytotypes, primarily tetraploids (4×) and octoploids (8×). Using a combination of genomic, quantitative genetic, landscape, and niche modeling approaches, we detect divergent levels of genetic admixture, evidence of niche differentiation, and differential environmental sensitivity between switchgrass cytotypes. Taken together, these findings support a generalist (8×)­specialist (4×) trade-off. Our results indicate that the 8× represent a unique combination of genetic variation that has allowed the expansion of switchgrass' ecological niche and thus putatively represents a valuable breeding resource.


Asunto(s)
Aclimatación , Panicum , Poliploidía , Aclimatación/genética , Variación Genética , Panicum/genética , Panicum/fisiología , Tetraploidía
2.
Gynecol Oncol ; 155(1): 39-50, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31427143

RESUMEN

OBJECTIVE: To examine the association between ovarian conservation and oncologic outcome in surgically-treated young women with early-stage, low-grade endometrial cancer. METHODS: This multicenter retrospective study examined women aged <50 with stage I grade 1-2 endometrioid endometrial cancer who underwent primary surgery with hysterectomy from 2000 to 2014 (US cohort n = 1196, and Japan cohort n = 495). Recurrence patterns, survival, and the presence of a metachronous secondary malignancy were assessed based on ovarian conservation versus oophorectomy. RESULTS: During the study period, the ovarian conservation rate significantly increased in the US cohort from 5.4% to 16.4% (P = 0.020) whereas the rate was unchanged in the Japan cohort (6.3-8.7%, P = 0.787). In the US cohort, ovarian conservation was not associated with disease-free survival (hazard ratio [HR] 0.829, 95% confidence interval [CI] 0.188-3.663, P = 0.805), overall survival (HR not estimated, P = 0.981), or metachronous secondary malignancy (HR 1.787, 95% CI 0.603-5.295, P = 0.295). In the Japan cohort, ovarian conservation was associated with decreased disease-free survival (HR 5.214, 95% CI 1.557-17.464, P = 0.007) and an increased risk of a metachronous secondary malignancy, particularly ovarian cancer (HR 7.119, 95% CI 1.349-37.554, P = 0.021), but was not associated with overall survival (HR not estimated, P = 0.987). Ovarian recurrence or metachronous secondary ovarian cancer occurred after a median time of 5.9 years, and all cases were salvaged. CONCLUSION: Our study suggests that adoption of ovarian conservation in young women with early-stage low-grade endometrial cancer varies by population. Ovarian conservation for young women with early-stage, low-grade endometrial cancer may be potentially associated with increased risks of ovarian recurrence or metachronous secondary ovarian cancer in certain populations; nevertheless, ovarian conservation did not negatively impact overall survival.


Asunto(s)
Carcinoma Endometrioide/epidemiología , Carcinoma Endometrioide/terapia , Neoplasias Endometriales/epidemiología , Neoplasias Endometriales/terapia , Neoplasias Primarias Secundarias/epidemiología , Tratamientos Conservadores del Órgano/estadística & datos numéricos , Ovario/fisiología , Adulto , Estudios de Cohortes , Supervivencia sin Enfermedad , Neoplasias Endometriales/cirugía , Femenino , Humanos , Histerectomía/métodos , Histerectomía/estadística & datos numéricos , Japón/epidemiología , Clasificación del Tumor , Estudios Retrospectivos , Estados Unidos/epidemiología
3.
Clin Exp Pharmacol Physiol ; 45(3): 269-277, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29029361

RESUMEN

Phosphodiesterase-5 (PDE-5) inhibitors induces vasodilation in several organs by blocking cyclic GMP (guanosine monophosphate) degradation. However, the existence of alternative mechanism of action in case of an impaired nitric oxide (NO) system remains controversial. Previous studies suggested that decreased NO bioavailability may result in the downregulation of klotho expression, but the relationship between klotho and NO remains obscure. Therefore, we investigated whether a PDE-5 inhibitor could preserve epithelial-mesenchymal transition (EMT) and relationship exists between the NO and renal klotho expression. Ten-week-old SD rats (N = 24, 200 g, male) were divided (N = 6) into four groups, which received: A LSD, L-NAME 1 mg/mL in drinking water, Udenafil 5 mg/kg subcutaneously and both for 4 weeks. Urine nitrate/nitrite, NGAL (Neutrophil gelatinase-associated lipocalin), and cGMP were measured using ELISA. Kidney was subjected to evaluate PCNA (proliferative cell nuclear antigen), α-SMA (smooth muscle cell antigen), E-cadherin, and klotho expression. Urine cGMP decreased after treatment of PDE-5 inhibitor compared with control due to blocking degradation of cGMP (P < .05, control vs Udenafil and L-NAME with Udenafil groups). Urine NGAL increased after treating of L-NAME and attenuated after using PDE-5 inhibitor (P < .05, control vs L-NAME and L-NAME with Udenafil). PCNA, α-SMA, and E-cadherin (EMT markers) increased after L-NAME treatment and normalized after using PDE-5 inhibitor. Klotho expression showed trend to increase in the L-NAME with PDE-5 inhibitor group compared with the L-NAME group, however, eNOS expression did not change after treatment of L-NAME or PDE-5 inhibitor compared with control. PDE-5 inhibitor alleviates EMT in the kidney via klotho modulation independent of the NO system.


Asunto(s)
Fosfodiesterasas de Nucleótidos Cíclicos Tipo 5/metabolismo , Glucuronidasa/metabolismo , Riñón/metabolismo , NG-Nitroarginina Metil Éster/farmacología , Inhibidores de Fosfodiesterasa 5/farmacología , Pirimidinas/farmacología , Sulfonamidas/farmacología , Animales , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 5/genética , Transición Epitelial-Mesenquimal , Regulación de la Expresión Génica/efectos de los fármacos , Glucuronidasa/genética , Riñón/efectos de los fármacos , Proteínas Klotho , Masculino , Óxido Nítrico/metabolismo , ARN/genética , ARN/metabolismo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena en Tiempo Real de la Polimerasa , Cloruro de Sodio Dietético/administración & dosificación
4.
Plant J ; 85(1): 161-76, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26590126

RESUMEN

Diatoms (Bacillarophyceae) are photosynthetic unicellular microalgae that have risen to ecological prominence in oceans over the past 30 million years. They are of interest as potential feedstocks for sustainable biofuels. Maximizing production of these feedstocks will require genetic modifications and an understanding of algal metabolism. These processes may benefit from genome-scale models, which predict intracellular fluxes and theoretical yields, as well as the viability of knockout and knock-in transformants. Here we present a genome-scale metabolic model of a fully sequenced and transformable diatom: Phaeodactylum tricornutum. The metabolic network was constructed using the P. tricornutum genome, biochemical literature, and online bioinformatic databases. Intracellular fluxes in P. tricornutum were calculated for autotrophic, mixotrophic and heterotrophic growth conditions, as well as knockout conditions that explore the in silico role of glycolytic enzymes in the mitochondrion. The flux distribution for lower glycolysis in the mitochondrion depended on which transporters for TCA cycle metabolites were included in the model. The growth rate predictions were validated against experimental data obtained using chemostats. Two published studies on this organism were used to validate model predictions for cyclic electron flow under autotrophic conditions, and fluxes through the phosphoketolase, glycine and serine synthesis pathways under mixotrophic conditions. Several gaps in annotation were also identified. The model also explored unusual features of diatom metabolism, such as the presence of lower glycolysis pathways in the mitochondrion, as well as differences between P. tricornutum and other photosynthetic organisms.


Asunto(s)
Biología Computacional , Diatomeas/metabolismo , Genoma/genética , Glucólisis , Redes y Vías Metabólicas , Modelos Biológicos , Biocombustibles , Simulación por Computador , Bases de Datos Factuales , Diatomeas/crecimiento & desarrollo , Microalgas , Mitocondrias/metabolismo , Fotosíntesis , Especificidad de la Especie
6.
Int Wound J ; 13(5): 630-5, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25091634

RESUMEN

The potential for adipose-derived stem cells to differentiate into keratinocyte-like cells has recently been receiving attention, stemming from the hypothesis that a bioengineered skin may be manufactured from these readily available mesenchymal stem cells. This study was conducted to evaluate the influence of human keratinocyte non-contact coculture on hADSCs. Human epidermal keratinocytes and hADSCs obtained by lipoaspiration were cultured in keratinogenic growth media, which were divided into the following groups: human adipose-derived stem cell (hADSC) monoculture, non-contact coculture of hADSCs and human keratinocytes and keratinocyte monoculture. Cell proliferation was assessed, and keratogenicity was analysed through immunocytochemistry and polymerase chain reaction of early, intermediate and late keratogenic markers. hADSCs cocultured with keratinocytes displayed enhanced proliferation compared with the monoculture group. After a 7-day coculture period, immunohistochemistry and polymerase chain reaction findings revealed the presence of specific keratinocyte markers in the coculture group. This study demonstrates that hADSCs cocultured with keratinocytes have the capacity to transdifferentiate into keratinocyte lineage cells, and suggests that adipose tissue may be a source of keratinocytes that may further be used in structuring the bioengineered skin.


Asunto(s)
Queratinocitos , Tejido Adiposo , Diferenciación Celular , Células Cultivadas , Técnicas de Cocultivo , Humanos , Células Madre Mesenquimatosas
7.
Arthroscopy ; 30(11): 1439-46, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25113259

RESUMEN

PURPOSE: This study compared the clinical and radiologic outcomes of arthroscopic medial meniscus root refixation using the modified Mason-Allen stitch and simple stitches. METHODS: The outcomes of 25 patients who underwent arthroscopic meniscus root refixation using the modified Mason-Allen stitch (M group) between June 2010 and January 2012 were compared with those of 25 matched control patients (S group) who underwent meniscus root refixation using simple stitches between March 2004 and August 2007. The Lysholm score, International Knee Documentation Committee Subjective Knee Form score, joint space narrowing, and Kellgren-Lawrence grade were assessed. Medial meniscal extrusion, progression of cartilage degeneration, and healing status of the refixed medial meniscus root were assessed on magnetic resonance images. RESULTS: No between-group difference was found in age, sex, body mass index, or preoperative patient characteristics. The mean follow-up times for the M and S groups were 24.1 and 25.9 months (P = .248), respectively. The Lysholm, International Knee Documentation Committee Subjective Knee Form, and Tegner activity scores improved significantly in both groups. The repaired root tended to heal better in the M group than in the S group (P = .065). Although the postoperative clinical outcomes did not differ between the groups, postoperative medial meniscal extrusion decreased -0.6 ± 0.9 mm in the M group and increased 1 ± 0.6 mm in the S group on magnetic resonance imaging (P < .001). The M group did not show significant progression in the Kellgren-Lawrence grade and cartilage degeneration (P = .083 and P = .317, respectively), whereas both measures increased significantly in the S group (P = .008 and P < .001, respectively). CONCLUSIONS: Compared with simple stitches, the modified Mason-Allen stitch improved the degree of meniscal extrusion, although the 2 different suture techniques showed no difference in clinical outcomes at short-term follow-up. LEVEL OF EVIDENCE: Level III, retrospective comparative study.


Asunto(s)
Meniscos Tibiales/cirugía , Reimplantación/métodos , Técnicas de Sutura , Lesiones de Menisco Tibial , Adulto , Artroscopía/métodos , Femenino , Humanos , Traumatismos de la Rodilla/cirugía , Laceraciones/cirugía , Imagen por Resonancia Magnética , Masculino , Meniscos Tibiales/diagnóstico por imagen , Persona de Mediana Edad , Radiografía , Estudios Retrospectivos , Rotura/cirugía , Cicatrización de Heridas
8.
Cogn Emot ; 27(1): 166-76, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22784014

RESUMEN

At attended locations emotion and attention interact to benefit contrast sensitivity, a basic visual dimension. Whether there are associated costs at unattended locations is unknown. Furthermore, emotion and attention affect response time, and anxiety modulates these effects. We investigated how trait-anxiety influences the interaction of emotion and attention on contrast sensitivity. On each trial, non-predictive pre-cues (neutral or fearful faces) directed exogenous attention to four contrast-varying, tilted stimuli (Gabor patches). Attention was cued toward the target (valid), a distracter (invalid), or distributed over all locations. Observers discriminated target orientation, and completed self-report measures of anxiety. Effects of fearful expressions were mediated by trait anxiety. Only high-trait-anxious individuals showed decreased target contrast sensitivity after attention was diverted to a distracter by a fearful cue, and anxiety score correlated with degree of impairment across participants. This indicates that increasing anxiety exacerbates threat-related attentional costs to visual perception, hampering processing at non-threat-related locations.


Asunto(s)
Ansiedad , Atención , Sensibilidad de Contraste/fisiología , Emociones , Temperamento , Adolescente , Adulto , Señales (Psicología) , Expresión Facial , Miedo , Femenino , Humanos , Masculino , Tiempo de Reacción
9.
Healthc (Amst) ; 9(4): 100581, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34626958

RESUMEN

The interleukin-6 receptor antagonist tocilizumab became widely used early in the coronavirus disease 2019 (COVID-19) pandemic based on small observational studies that suggested clinical benefit in COVID-19 patients with a hyperinflammatory state. To inform our local treatment algorithms in the absence of randomized clinical trial results, we performed a rapid analysis of the first 11 hospitalized COVID-19 patients treated with tocilizumab at our academic medical center. We report their early clinical outcomes and describe the process by which we assembled a team of diverse trainees and stakeholders to extract, analyze, and disseminate data during a time of clinical uncertainty.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Anticuerpos Monoclonales Humanizados , Toma de Decisiones Clínicas , Síndrome de Liberación de Citoquinas , Humanos , Uso Fuera de lo Indicado , Pandemias , SARS-CoV-2 , Resultado del Tratamiento , Incertidumbre
10.
Eur J Cancer ; 133: 56-65, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32442924

RESUMEN

BACKGROUND: This study assessed the effects of gonadotropin-releasing hormone agonists (GnRHa) on the prevention of chemotherapy-induced ovarian insufficiency among young patients with malignant ovarian germ cell tumour (MOGCT) receiving chemotherapy. METHODS: This multicentre, retrospective study was conducted at 15 sites affiliated with the Korean Gynecologic Oncology Group and enrolled 354 patients between January 1995 and September 2018. Among them, 227 patients were included in this study and divided into two groups according to the use of GnRHa during chemotherapy (GnRHa versus no GnRHa groups). The primary objective was to compare the rates of menstrual resumption between the two groups. We also assessed the clinical determinants affecting menstrual resumption among the study groups. RESULTS: There were no significant differences between the GnRHa (n = 63) and no GnRHa (n = 164) groups regarding age at diagnosis, parity, ethnicity, age at menarche, body mass index, International Federation of Gynecology and Obstetrics stage, mode of surgery and surgery type. The rate of menstrual resumption after chemotherapy was 100% (63 of 63) in the GnRHa group and 90.9% (149 of 164) in the no GnRHa group (p = 0.013). The mean periods from last chemotherapy to menstrual resumption were 7.4 and 7.3 months in the GnRHa and no GnRHa groups, respectively. GnRHa co-administration during chemotherapy reduced the likelihood of amenorrhoea after chemotherapy, although statistical significance was not confirmed in the univariate analysis (odds ratio: 0.276; 95% confidence interval, 0.004-1.317; p = 0.077). CONCLUSION: Temporary ovarian suppression with GnRHa during chemotherapy does not significantly increase the chances of menstrual resumption in young patients with MOGCT.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Fármacos para la Fertilidad Femenina/uso terapéutico , Hormona Liberadora de Gonadotropina/agonistas , Neoplasias de Células Germinales y Embrionarias/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Insuficiencia Ovárica Primaria/inducido químicamente , Insuficiencia Ovárica Primaria/prevención & control , Adolescente , Adulto , Amenorrea/inducido químicamente , Amenorrea/epidemiología , Amenorrea/prevención & control , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Bleomicina/administración & dosificación , Bleomicina/efectos adversos , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Etopósido/administración & dosificación , Etopósido/efectos adversos , Estudios de Factibilidad , Femenino , Preservación de la Fertilidad/métodos , Humanos , Infertilidad Femenina/inducido químicamente , Infertilidad Femenina/epidemiología , Infertilidad Femenina/prevención & control , Menopausia Prematura/efectos de los fármacos , Menstruación/efectos de los fármacos , Neoplasias de Células Germinales y Embrionarias/epidemiología , Neoplasias Ováricas/epidemiología , Ovario/efectos de los fármacos , Embarazo , Insuficiencia Ovárica Primaria/epidemiología , República de Corea/epidemiología , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
11.
J Gastroenterol Hepatol ; 23(5): 811-6, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-17995941

RESUMEN

BACKGROUND AND AIM: Systemic treatments of advanced hepatocellular carcinoma (AHCC) have offered marginal clinical benefits. Recently, Italian investigators reported that etoposide and epirubicin combination (EE) chemotherapy was highly active against AHCC, with a response rate of 39% and a median overall survival (OS) of 10 months. We report our efficacy and safety results of EE in clinical practice. METHODS: Between December 1999 and October 2005, 35 patients with AHCC and fitting the preset eligibility criteria were treated with EE. Twenty-eight patients (80%) had liver disease associated with hepatitis B virus (HBV) and 26 (74%) had a prior history of transarterial chemoembolization (TACE) using cisplatin. The EE chemotherapy consisted of epirubicin 40 mg/m(2) on day 1 and etoposide 120 mg/m(2) on days 1, 3 and 5 every 4 weeks. RESULTS: A total of 102 chemotherapy cycles were administered, with a median of two cycles per patient (range one to eight cycles). Two patients had a partial response and nine had stable disease, with a tumor control rate of 32% (95% CI 17-48). The median progression-free survival (PFS) was 2.1 months (95% CI 1.8-2.4) and the median OS was 6.4 months (95% CI 4.4-8.5). There was a tendency toward improved PFS in patients seronegative for HBsAg and peritoneal seeding (P = 0.06 and P = 0.054, respectively). Overall survival was significantly better in patients without HBsAg and Cancer Liver Italian Program (CLIP) score 0-1 (P = 0.024 and P = 0.033, respectively). The main toxicities were hematological events, including grade 3/4 neutropenia in 29% and febrile neutropenia in 11% of patients. CONCLUSION: Treatment with EE showed minimal antitumor activity with acceptable toxicity in HBV-associated AHCC, especially in patients pretreated with TACE.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Adolescente , Adulto , Anciano , Carcinoma Hepatocelular/patología , Epirrubicina/administración & dosificación , Etopósido/administración & dosificación , Femenino , Humanos , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Retrospectivos
12.
J Glaucoma ; 25(11): 873-878, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27814326

RESUMEN

PURPOSE: To investigate the consistency of Bruch membrane opening (BMO) detection as determined by Cirrus high-definition optical coherence tomography (OCT). MATERIALS AND METHODS: This study enrolled 106 healthy eyes and 194 glaucomatous eyes who underwent OCT examinations. The location of BMO was evaluated by inspecting 72 cross-sectional optic nerve head (ONH) images (5 degrees intervals for 360 degrees) per eye in which BMO location is automatically detected by the OCT algorithm. The consistency of BMO detection was investigated by comparing consecutive cross-sectional ONH images. If the location of the BMO margin did not agree between images, it was considered as inconsistent BMO detection. RESULTS: Among 300 eyes, 21 (7.0%) showed inconsistent BMO detection. Inconsistency in BMO detection was associated with a higher degree of myopia (P<0.001). All inconsistent BMO detection was found in areas with ß-zone peripapillary atrophy. Eyes with inconsistent BMO detection showed greater changes in ONH parameters and retinal nerve fiber layer thickness than eyes with consistent BMO detection (P<0.001). CONCLUSIONS: Although BMO locations were consistent in most cases, in some cases, there were inconsistencies in BMO locations determined by OCT, especially in myopic eyes with peripapillary atrophy. Inconsistency in BMO detection resulted in changes in ONH parameters and retinal nerve fiber layer thickness. These finding should be considered when assessing glaucoma by using OCT.


Asunto(s)
Lámina Basal de la Coroides/diagnóstico por imagen , Glaucoma de Ángulo Abierto/diagnóstico , Fibras Nerviosas/patología , Disco Óptico/diagnóstico por imagen , Células Ganglionares de la Retina/patología , Tomografía de Coherencia Óptica , Adulto , Anciano , Algoritmos , Estudios Transversales , Femenino , Humanos , Presión Intraocular , Masculino , Persona de Mediana Edad , Enfermedades del Nervio Óptico/diagnóstico , Tomografía de Coherencia Óptica/métodos
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