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This Viewpoint discusses the overturning of Roe v Wade and subsequent banning of abortion or placement of gestational limits in almost half of US states, and the potential effects that such policies will have on the ability to recruit and retain health care professionals in these states.
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Aborto Inducido , Aborto Legal , Médicos , Población Rural , Femenino , Humanos , Embarazo , Decisiones de la Corte Suprema , Estados Unidos/epidemiología , Población Rural/estadística & datos numéricos , Médicos/estadística & datos numéricos , Médicos/provisión & distribución , Médicos/tendenciasRESUMEN
A racially and ethnically diverse health care workforce remains a distant goal, the attainment of which is contingent on the inclusivity of the national medical student body. We examined the diversity of medical school applicants and enrollees over the past four decades with an eye toward assessing the progress made. Data on the gender and race or ethnic group of enrollees in all medical doctorate degree-granting U.S. medical schools from 1978 through 2019 were examined. The percentage of female enrollees doubled during this period, and women now constitute more than half the national medical student body. This upturn has been attributed largely to an increase by a factor of 12 in the enrollment of Asian women. The corresponding decrease in the percentage of male enrollees, most notably White men, was offset by an increase by a factor of approximately 5 in the enrollment of Asian men. The percentages of enrollees from Black, Hispanic, and other racial and ethnic groups that are underrepresented in medicine remain well below the percentages of these groups in the national Census.
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Diversidad Cultural , Etnicidad/estadística & datos numéricos , Facultades de Medicina/tendencias , Estudiantes de Medicina/estadística & datos numéricos , Femenino , Humanos , Masculino , Grupos Minoritarios/estadística & datos numéricos , Criterios de Admisión Escolar , Estados UnidosRESUMEN
Crop yield is challenged every year worldwide by changing climatic conditions. The forecasted climatic scenario urgently demands stress-tolerant crop varieties to feed the ever-increasing global population. Molecular breeding and genetic engineering approaches have been frequently exploited for developing crops with desired agronomic traits. Recently, microRNAs (miRNAs) have emerged as powerful molecules, which potentially serve as expression markers during stress conditions. The miRNAs are small non-coding endogenous RNAs, usually 20-24 nucleotides long, which mediate post-transcriptional gene silencing and fine-tune the regulation of many abiotic- and biotic-stress responsive genes in plants. The miRNAs usually function by specifically pairing with the target mRNAs, inducing their cleavage or repressing their translation. This review focuses on the exploration of the functional role of miRNAs in regulating plant responses to abiotic and biotic stresses. Moreover, a methodology is also discussed to mine stress-responsive miRNAs from the enormous amount of transcriptome data available in the public domain generated using next-generation sequencing (NGS). Considering the functional role of miRNAs in mediating stress responses, these molecules may be explored as novel targets for engineering stress-tolerant crop varieties.
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The present study reports engineered cold tolerance and toxicity analysis in genetically modified tomato (Solanum lycopersicum L. cv. Pusa Ruby) developed through constitutive over expression of Nicotiana tabacum Osmotin gene. Rate of seed germination, seedling establishment and growth remained unaffected in the transgenic tomato in response to a low temperature (15 °C) treatment, but were significantly (P ≤ 0.05) reduced in the wild type. At reproductive stage, the wild type plants failed to recover at the low temperature (4.0 °C) treatment for 10 days but the transgenic plants survived successfully without any leaf senescence or other visible chilling injury symptoms. The quantitative transcript expression analysis confirmed up regulation of the transgene by 55% in the transgenic plants on cold treatment for 2 h whereas, the transcripts were not detected in the wild type. Containment evaluation under normal environmental conditions revealed similar morphology in both the transgenic and wild type tomato plants however an average fruit yield was higher in the transgenic plants (725.91 ± 39.27 g) than the wild type (679.84 ± 28.80 g). The composition of mature fruits in terms of element content was at par in both the transgenic and wild type except significantly higher Ca and Mg contents in the transgenic fruits than that of the wild type. Further, acute and sub-acute toxicity tests conducted in the adult female Wister rats revealed no mortality or significant changes in general and psychological behaviour, at par food intake and body weight and, normal biochemical, and hematological parameters for animals fed with the wild type or transgenic tomato fruits as compared to the control group, confirming its safety for animal consumption.
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Documentación , Tabla de Aranceles/organización & administración , Medicaid , Medicare , Tabla de Aranceles/economía , Humanos , Medicaid/economía , Medicaid/organización & administración , Medicare/economía , Medicare/organización & administración , Neoplasias Faríngeas/economía , Neoplasias Faríngeas/terapia , Faringitis/economía , Faringitis/terapia , Estados UnidosRESUMEN
NAC genes contribute to enhance survivability of plants under conditions of environmental stress and in secondary growth of the plants, thereby building biomass. Thus, genetic transformation of plants using NAC genes provides a possibility to tailor biofuel plants. Over-expression studies have indicated that NAC family genes can provide tolerance to various biotic and abiotic stresses, either by physiological or biochemical changes at the cellular level, or by affecting visible morphological and anatomical changes, for example, by development of lateral roots in a number of plants. Over-expression of these genes also work as triggers for development of secondary cell walls. In our laboratory, we have observed a NAC gene from Lepidium latifolium contributing to both enhanced biomass as well as cold stress tolerance of model plants tobacco. Thus, we have reviewed all the developments of genetic engineering using NAC genes which could enhance the traits required for biofuel plants, either by enhancing the stress tolerance or by enhancing the biomass of the plants.
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There is much debate about the adequacy of the U.S. physician workforce and projections of its future size, distribution and composition. Beginning with 3 observations about the workforce we believe are largely not subject to dispute, we address the debate by providing an overview of the current state of the workforce and Graduate Medical Education in the United States; a brief history of both calls for graduate medical education reform since 1910 and the recent, intense debate about the reliability of workforce projections; and a discussion of the challenges to understanding the physician workforce. We draw 3 concluding observations: (1) Precisely because projections can be unpredictable in their impact on both physician workforce behavior and public policy development, policy makers need to devote more attention to workforce projections, not less. (2) More research devoted specifically to the workforce implications of delivery and payment reforms is strongly needed. (3) Such research must be pursued with a sense of urgency, given the rapid aging of the Baby Boom generation, which will put a disproportionate demand on the nation's physician workforce.
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Educación de Postgrado en Medicina/historia , Médicos/estadística & datos numéricos , Médicos/tendencias , Educación de Postgrado en Medicina/organización & administración , Educación de Postgrado en Medicina/tendencias , Política de Salud , Historia del Siglo XX , Historia del Siglo XXI , Médicos/economía , Médicos/organización & administración , Médicos/provisión & distribución , Estados UnidosRESUMEN
Molecular markers, due to their stability, cost-effectiveness and ease of use provide an immensely popular tool for a variety of applications including genome mapping, gene tagging, genetic diversity diversity, phylogenetic analysis and forensic investigations. In the last three decades, a number of molecular marker techniques have been developed and exploited worldwide in different systems. However, only a handful of these techniques, namely RFLPs, RAPDs, AFLPs, ISSRs, SSRs and SNPs have received global acceptance. A recent revolution in DNA sequencing techniques has taken the discovery and application of molecular markers to high-throughput and ultrahigh-throughput levels. Although, the choice of marker will obviously depend on the targeted use, microsatellites, SNPs and genotyping by sequencing (GBS) largely fulfill most of the user requirements. Further, modern transcriptomic and functional markers will lead the ventures onto high-density genetic map construction, identification of QTLs, breeding and conservation strategies in times to come in combination with other high throughput techniques. This review presents an overview of different marker technologies and their variants with a comparative account of their characteristic features and applications.
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Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Marcadores Genéticos/genética , Repeticiones de Microsatélite/genética , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo de Nucleótido Simple/genética , Técnicas de Genotipaje , Análisis de Secuencia de ADNRESUMEN
We report elevated biomass and altered growth characteristics of tobacco plants up on transformation with a NAC (NAM, ATAF1/2,CUC2) gene (GenBank Accession FJ754254) isolated from Lepidium latifolium L. (LlaNAC). Transgenic plants showed significant differences in fresh weight, midrib length of longest leaf, leaf area, height of the plant, root and shoot weights, etc. during vegetative phase. On 100th day after sowing (DAS), plants of transgenic lines were 2-3 times taller than the wild type plants, though no significant difference was recorded in moisture contents of any of the plant tissues. Over-expression of NAC gene up to 2,000 fold was recorded in leaves of transgenic plants on 100th DAS. Interestingly, transgenic plants showed significantly shortened (P(t) = 0.02-0.04) life cycle, as they showed a completely altered growth behaviour. Transgenic plants entered reproductive phase earlier by 60 days, with lines NC2 and NC7b entering first, followed by line NC10. However, the time period spent in the reproductive phase by the plant was nearly twice in case of transgenic lines NC2, NC7b and NC10, as compared to the wild type plants. Despite that, these lines completed their life cycle in 45-60 days lesser than the time taken by wild-type tobacco plants. No difference was recorded in fruit and seed yield of transgenic or wild type plants. To the best of our knowledge, this is the first report on over-expression of NAC gene causing altered growth and biomass patterns. We expect this study to become an important reference towards future engineering of plants for fuel and fodder purposes.
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Biocombustibles , Regulación de la Expresión Génica de las Plantas/fisiología , Ingeniería Genética/métodos , Lepidium/genética , Nicotiana/crecimiento & desarrollo , Proteínas de Plantas/genética , Transformación Genética/genética , Aclimatación/genética , Biomasa , Frío , Regulación de la Expresión Génica de las Plantas/genética , Lepidium/metabolismo , Estadios del Ciclo de Vida/genética , Nicotiana/genéticaRESUMEN
Ran is a multifunctional small GTPase involved in important cellular activities like nucleocytoplasmic transport, mitotic spindle assembly, nuclear envelope formation, etc., but is also known to be differentially expressed in response to abiotic stress, particularly low temperature. We have over-expressed Lepidium latifolium (Fam. Brassicaceae) Ran gene in tobacco to study the response of the plants to cold stress (24 h; 4 °C). Transformation of the tobacco plants was verified using PCR targeting Ran gene and co-transformed selectable marker gene nptII. Segregation in Mendelian ratios was validated in five transgenic lines by germination of T1 and T2 seeds on moist filter papers containing 150 mg/l kanamycin. Higher levels of electrolyte leakage and lipid peroxidation pointed towards hypersensitivity of plants. Similarly, lesser proline accumulation compared to wild types also indicated susceptibility of plants to death under chilling conditions. Specific activity of antioxidant enzymes superoxide dismutase and glutathione reductase was also measured under stressed and control conditions. A variation was observed across the different lines, and four out of five lines showed lesser specific activity compared to wild type plants, thus indicating reduced capability of scavenging free radicals. In totality, a strong evidence on induced hypersensitivity to cold stress has been collected which may further be helpful in designing appropriate strategies for engineering crop plants for survival under cold stress conditions.
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Respuesta al Choque por Frío/genética , Lepidium/genética , Nicotiana/genética , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente/genética , Proteína de Unión al GTP ran/genética , Genes de Plantas , Glutatión Reductasa/metabolismo , Peroxidación de Lípido/genética , Plantas Modificadas Genéticamente/metabolismo , Superóxido Dismutasa/metabolismo , Transgenes , Regulación hacia ArribaRESUMEN
We have isolated and in silico characterized a cold regulated plastocyanin encoding gene from Lepidium latifolium L designated as LlaDRT. Its cDNA sequence (JN214346) consists of a 504 bp ORF, 48 and 205 bp of 5' and 3' UTR regions, respectively encoding a protein of 17.07 KDa and pI 4.95. In silico and phylogenetic analysis of LlaDRT suggested that the protein has features of a typical plastocyanin family member and of a nearest relative of the predominant isoform of Arabidopsis (PETE2) plastocyanin. Validation of stress response of LlaDRT by qPCR under different abiotic stress regulators viz salicylic acid, jasmonic acid, calcium chloride, ethylene and abscisic acid revealed its possible regulation and crosstalk amongst different pathways.
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Lepidium/genética , Secuencia de Aminoácidos , Clonación Molecular , Biología Computacional , Daño del ADN/genética , Reparación del ADN/genética , ADN Complementario/genética , Regulación de la Expresión Génica de las Plantas , Intrones , Lepidium/metabolismo , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Semillas/química , Estrés Fisiológico/efectos de los fármacos , Estrés Fisiológico/genéticaRESUMEN
Oil-rich seeds of Jatropha curcas are being focussed as a source of bio-diesel. However, prior to its industrial use, a lot of crop improvement efforts are required in Jatropha. Availability of a large number of EST sequences of Jatropha in public domain allow identification of candidate genes for several agronomic characters including oil content in seeds. Here, we have analysed 42,477 ESTs of Jatropha spanning 22.9 Mbp for microsatellites and fatty acid metabolism related sequences. Unigene sequences were built using CAP 3 programme resulted in 12,358 contigs and 5,730 singlets. Nearly, 8 % unigenes showed presence of microsatellites, slightly over-represented compared to their occurrence in ESTs. Most of the microsatellites were either di- or tri-nucleotide repeats, while other categories of tetra-, penta- and hexa-nucleotide repeats together constituted ~4 % of total microsatellites. Assessment of functional relevance of unigenes was carried out using Blast2GO using its default settings. The overall sequence similarity level against sequences in 'nr' database was >80 %. A total of 931 sequences that participated in any of the pathways related to fatty acid or lipid metabolism were found at GO level 6. Among these, GO terms "Fatty acid metabolic process" and "Fatty acid biosynthetic process" were most over-represented. Overall, our work has due relevance in identifying molecular markers for the candidate genes for oil content in Jatropha seeds, and will prove to be an important reference for further studies for identification of trait specific markers in Jatropha.
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Curcin, a type I ribosomal inhibiting protein-RIP, encoded by curcin precursor gene, is a phytotoxin present in Jatropha (Jatropha curcas L.). Here, we report designing of RNAi construct for the curcin precursor gene and further its genetic transformation of Jatropha to reduce its transcript expression. Curcin precursor gene was first cloned from Jatropha strain DARL-2 and part of the gene sequence was cloned in sense and antisense orientation separated by an intron sequence in plant expression binary vector pRI101 AN. The construction of the RNAi vector was confirmed by double digestion and nucleotide sequencing. The vector was then mobilized into Agrobacterium tumefaciens strain GV 3101 and used for tissue culture independent in planta transformation protocol optimized for Jatropha. Germinating seeds were injured with a needle before infection with Agrobacterium and then transferred to sterilized sand medium. The seedlings were grown for 90 days and genomic DNA was isolated from leaves for transgenic confirmation based on real time PCR with NPT II specific dual labeled probe. Result of the transgenic confirmation analysis revealed presence of the gene silencing construct in ten out of 30 tested seedlings. Further, quantitative transcript expression analysis of the curcin precursor gene revealed reduction in the transcript abundance by more than 98% to undetectable level. The transgenic plants are being grown in containment for further studies on reduction in curcin protein content in Jatropha seeds.
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Regulación de la Expresión Génica de las Plantas , Silenciador del Gen , Jatropha/genética , ARN Mensajero/antagonistas & inhibidores , Proteínas Inactivadoras de Ribosomas Tipo 1/antagonistas & inhibidores , Semillas/genética , Toxinas Biológicas/antagonistas & inhibidores , Agrobacterium tumefaciens/genética , Biocombustibles , Técnicas de Transferencia de Gen , Vectores Genéticos , Jatropha/crecimiento & desarrollo , Jatropha/toxicidad , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/crecimiento & desarrollo , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Proteínas Inactivadoras de Ribosomas Tipo 1/biosíntesis , Proteínas Inactivadoras de Ribosomas Tipo 1/genética , Semillas/crecimiento & desarrollo , Toxinas Biológicas/biosíntesis , Toxinas Biológicas/genéticaRESUMEN
Traditionally, projections of US health care demand have been based upon a combination of existing trends in usage and idealized or expected delivery system changes. For example, 1990s health care demand projections were based upon an expectation that delivery models would move toward closed, tightly managed care networks and would greatly decrease the demand for subspecialty care. Today, however, a different equation is needed on which to base such projections. Realistic workforce planning must take into account the fact that expanded access to health care, a growing and aging population, increased comorbidity, and longer life expectancy will all increase the use of health care services per capita over the next few decades--at a time when the number of physicians per capita will begin to drop. New technologies and more aggressive screening may also change the equation. Strategies to address these increasing demands on the health system must include expanded physician training.
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Tecnología Biomédica/tendencias , Atención a la Salud/tendencias , Reforma de la Atención de Salud , Necesidades y Demandas de Servicios de Salud/tendencias , Fuerza Laboral en Salud/tendencias , Médicos/provisión & distribución , Calidad de la Atención de Salud , Humanos , Estados UnidosRESUMEN
Workforce planning in an era of health care reform is a challenge as both delivery systems and patient demographics change. Current workforce projections are based on a future health care system that is either an identified "ideal" or a modified version of the existing system. The desire to plan for such an "ideal system," however, may threaten access to necessary services if it does not come to fruition or is based on theoretical rather than empirical data.Historically, workforce planning that concentrated only on an "ideal system" has been centered on incorrect assumptions. Two examples of such failures presented in the 1980s when the Graduate Medical Education National Advisory Committee recommended a decrease in the physician workforce on the basis of predetermined "necessary and appropriate" services and in the 1990s, when planners expected managed care and health maintenance organizations to completely overhaul the existing health care system. Neither accounted for human behavior, demographic changes, and actual demand for health care services, leaving the nation ill-prepared to care for an aging population with chronic disease.In this article, the authors argue that workforce planning should begin with the current system and make adjustments based on empirical data that accurately reflect current trends. Actual health care use patterns will become evident as systemic changes are realized-or not-over time. No single approach will solve the looming physician shortage, but the danger of planning only for an ideal system is being unprepared for the actual needs of the population.
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Reforma de la Atención de Salud/organización & administración , Necesidades y Demandas de Servicios de Salud/tendencias , Fuerza Laboral en Salud/organización & administración , Evaluación de Necesidades/organización & administración , Médicos/provisión & distribución , Predicción , Humanos , Evaluación de Necesidades/tendencias , Patient Protection and Affordable Care Act , Médicos/organización & administración , Médicos/tendencias , Estados UnidosRESUMEN
Recent studies suggest that team-based primary care models could contribute to eliminating the predicted physician shortages. In this article, the authors explore existing team-based clinical care delivery models, comparing specialist and primary care teams, that include patient-centered medical homes and accountable care organizations. Next, the authors describe the barriers to adopting these models on a large scale, particularly the regulatory, financial, and cultural factors as well as scope of practice considerations for nonphysician providers. The authors' aim is not to evaluate the merits of team-based primary care models but, rather, to ascertain whether such models should be at the center of current physician workforce planning policies. The authors argue that although emerging evidence indicates that primary care teams can improve patient outcomes, few data exist to suggest that these models will drastically reduce the need for additional physicians or other providers. Thus, the authors conclude that additional research is needed to evaluate the ability of such models to alleviate provider deficits. And, while policy makers should work toward their ideal health care system, they also must expand the physician workforce to meet the growing demand for health care services in the existing one.