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1.
Proc Natl Acad Sci U S A ; 119(15): e2106743119, 2022 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-35389750

RESUMEN

Human culture, biology, and health were shaped dramatically by the onset of agriculture ∼12,000 y B.P. This shift is hypothesized to have resulted in increased individual fitness and population growth as evidenced by archaeological and population genomic data alongside a decline in physiological health as inferred from skeletal remains. Here, we consider osteological and ancient DNA data from the same prehistoric individuals to study human stature variation as a proxy for health across a transition to agriculture. Specifically, we compared "predicted" genetic contributions to height from paleogenomic data and "achieved" adult osteological height estimated from long bone measurements for 167 individuals across Europe spanning the Upper Paleolithic to Iron Age (∼38,000 to 2,400 B.P.). We found that individuals from the Neolithic were shorter than expected (given their individual polygenic height scores) by an average of −3.82 cm relative to individuals from the Upper Paleolithic and Mesolithic (P = 0.040) and −2.21 cm shorter relative to post-Neolithic individuals (P = 0.068), with osteological vs. expected stature steadily increasing across the Copper (+1.95 cm relative to the Neolithic), Bronze (+2.70 cm), and Iron (+3.27 cm) Ages. These results were attenuated when we additionally accounted for genome-wide genetic ancestry variation: for example, with Neolithic individuals −2.82 cm shorter than expected on average relative to pre-Neolithic individuals (P = 0.120). We also incorporated observations of paleopathological indicators of nonspecific stress that can persist from childhood to adulthood in skeletal remains into our model. Overall, our work highlights the potential of integrating disparate datasets to explore proxies of health in prehistory.


Asunto(s)
Agricultura , Estatura , Agricultores , Salud , Esqueleto , Adulto , Agricultura/historia , Estatura/genética , Niño , ADN Antiguo , Europa (Continente) , Agricultores/historia , Variación Genética , Genómica , Salud/historia , Historia Antigua , Humanos , Paleopatología , Esqueleto/anatomía & histología
2.
Sci Adv ; 7(35)2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34433570

RESUMEN

Europe's prehistory oversaw dynamic and complex interactions of diverse societies, hitherto unexplored at detailed regional scales. Studying 271 human genomes dated ~4900 to 1600 BCE from the European heartland, Bohemia, we reveal unprecedented genetic changes and social processes. Major migrations preceded the arrival of "steppe" ancestry, and at ~2800 BCE, three genetically and culturally differentiated groups coexisted. Corded Ware appeared by 2900 BCE, were initially genetically diverse, did not derive all steppe ancestry from known Yamnaya, and assimilated females of diverse backgrounds. Both Corded Ware and Bell Beaker groups underwent dynamic changes, involving sharp reductions and complete replacements of Y-chromosomal diversity at ~2600 and ~2400 BCE, respectively, the latter accompanied by increased Neolithic-like ancestry. The Bronze Age saw new social organization emerge amid a ≥40% population turnover.

3.
Ceska Slov Farm ; 70(1): 3-6, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34237947

RESUMEN

The paper deals with developing the national part of the Czech Pharmacopoeia 2017 (CL 2017) in its supplements from 2018, 2019, and 2020. It focuses on the preparation of medicinal products in pharmacies. The possibilities of further developing the national part of the CL 2017 to accelerate the necessary changes in its content are also discussed.


Asunto(s)
Farmacias , República Checa , Composición de Medicamentos
4.
PLoS One ; 16(4): e0246662, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33852578

RESUMEN

In the 12,000 years preceding the Industrial Revolution, human activities led to significant changes in land cover, plant and animal distributions, surface hydrology, and biochemical cycles. Earth system models suggest that this anthropogenic land cover change influenced regional and global climate. However, the representation of past land use in earth system models is currently oversimplified. As a result, there are large uncertainties in the current understanding of the past and current state of the earth system. In order to improve representation of the variety and scale of impacts that past land use had on the earth system, a global effort is underway to aggregate and synthesize archaeological and historical evidence of land use systems. Here we present a simple, hierarchical classification of land use systems designed to be used with archaeological and historical data at a global scale and a schema of codes that identify land use practices common to a range of systems, both implemented in a geospatial database. The classification scheme and database resulted from an extensive process of consultation with researchers worldwide. Our scheme is designed to deliver consistent, empirically robust data for the improvement of land use models, while simultaneously allowing for a comparative, detailed mapping of land use relevant to the needs of historical scholars. To illustrate the benefits of the classification scheme and methods for mapping historical land use, we apply it to Mesopotamia and Arabia at 6 kya (c. 4000 BCE). The scheme will be used to describe land use by the Past Global Changes (PAGES) LandCover6k working group, an international project comprised of archaeologists, historians, geographers, paleoecologists, and modelers. Beyond this, the scheme has a wide utility for creating a common language between research and policy communities, linking archaeologists with climate modelers, biodiversity conservation workers and initiatives.


Asunto(s)
Arqueología , Recursos Naturales , Arabia , Biodiversidad , Clima , Conservación de los Recursos Naturales , Manejo de Datos , Planeta Tierra , Ecosistema , Historia Antigua , Humanos , Mesopotamia
5.
Ceska Slov Farm ; 67(5-6): 192-199, 2018 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-30871324

RESUMEN

BACKGROUND: Medication wastage is an important factor that contributes to escalating healthcare costs. Medication wastage may be due to poor compliance of patients, excessive and irrational prescribing, or a lack of control of the dispensing of prescription medications in the community pharmacy. OBJECTIVE: To describe and analyze the situation regarding the unused medicines from the quantitative, qualitative and financial point of view, their cost to the public healthcare system, and behaviours regarding medication wastage of the Czech population. METHOD: The analysed material consisted of medicines returned to 66 community pharmacies in the Czech Republic between May 16 and June 29, 2012. Thorough analysis was aimed only at medicinal products. MAIN OUTCOME MEASURE: The analysis of the returned medicines according to the price, amount, therapeutic group, active substance and brand name. RESULTS: In the analysed material there were 18,890 items. The number of returned medicines was 16,520 products. The total value of these products was calculated at about Czech crowns (CZK) 2.1 mil., approx. Euro (EUR) 82,000. Reimbursement of health insurance companies was about CZK 1.4 mil. (approx. EUR 55,000). The most frequently returned drugs were medicines acting on the cardiovascular system (17.0%). The most frequent active substance was paracetamol, which recurred 405 times. CONCLUSION: The results about the unused medicines from the quantitative, qualitative and financial perspectives describe the situation not only for medicines policy makers and adjustment of the systems of pricing and reimbursement policies, but also for safer and more effective pharmaceutical care and strengthening of the function of community pharmacies.


Asunto(s)
Costos de los Medicamentos , Farmacias/economía , Comercio , República Checa
6.
Archaeometry ; 58(3): 513-528, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30283156

RESUMEN

This paper examines the possibilities of creating quantified models of past human activities in both time and space. The study area lies in the southeastern Czech Republic and western Slovakia. The spatio-temporal model of behavioural categories was calculated with the help of Monte Carlo simulations and statistical testing. One of the main advantages of our approach is that it admits the probabilistic nature of input data, quantifies them and provides probabilistic results comparable with other proxies. It also presents a less biased way of how archaeological data from regions and periods with low numbers of 14C datings can be incorporated into models of past population dynamics.

7.
Archaeol Anthropol Sci ; 10(5): 1153-1164, 2016 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-30294383

RESUMEN

The population boom-and-bust during the European Neolithic (7000-2000 BC) has been the subject of lively discussion for the past decade. Most of the research on this topic was carried out with help of summed radiocarbon probability distributions. We aim to reconstruct population dynamics within the catchment of a medium sized lake on the basis of information on the presence of all known past human activities. We calculated a human activity model based on Monte Carlo simulations. The model showed the lowest level of human activity between 4000 and 3000 BC. For a better understanding of long-term socio-environmental dynamics, we also used the results of a pollen-based quantitative vegetation model, as well as a local macrophysical climate model. The beginning of the decline of archaeologically visible human activities corresponds with climatic changes and an increase in secondary forest taxa probably indicating more extensive land-use. In addition, important social and technological innovations, such as the introduction of the ard, wheel, animal traction and metallurgy, as well as changes in social hierarchy characterizing the same period.

8.
Nature ; 522(7555): 167-72, 2015 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-26062507

RESUMEN

The Bronze Age of Eurasia (around 3000-1000 BC) was a period of major cultural changes. However, there is debate about whether these changes resulted from the circulation of ideas or from human migrations, potentially also facilitating the spread of languages and certain phenotypic traits. We investigated this by using new, improved methods to sequence low-coverage genomes from 101 ancient humans from across Eurasia. We show that the Bronze Age was a highly dynamic period involving large-scale population migrations and replacements, responsible for shaping major parts of present-day demographic structure in both Europe and Asia. Our findings are consistent with the hypothesized spread of Indo-European languages during the Early Bronze Age. We also demonstrate that light skin pigmentation in Europeans was already present at high frequency in the Bronze Age, but not lactose tolerance, indicating a more recent onset of positive selection on lactose tolerance than previously thought.


Asunto(s)
Pueblo Asiatico/genética , Evolución Cultural/historia , Fósiles , Genoma Humano/genética , Genómica , Lenguaje/historia , Población Blanca/genética , Arqueología/métodos , Asia/etnología , ADN/genética , ADN/aislamiento & purificación , Europa (Continente)/etnología , Frecuencia de los Genes/genética , Genética de Población , Historia Antigua , Migración Humana/historia , Humanos , Intolerancia a la Lactosa/genética , Polimorfismo de Nucleótido Simple/genética , Pigmentación de la Piel/genética
9.
Quat Sci Rev ; 116: 15-27, 2015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-28522887

RESUMEN

The post-glacial fate of central European grasslands has stimulated palaeoecological debates for a century. Some argued for the continuous survival of open land, while others claimed that closed forest had developed during the Middle Holocene. The reasons behind stability or changes in the proportion of open land are also unclear. We aim to reconstruct regional vegetation openness and test the effects of climate and human impact on vegetation change throughout the Holocene. We present a newly dated pollen record from north-western fringes of the Pannonian Plain, east-central Europe, and reconstruct Holocene regional vegetation development by the REVEALS model for 27 pollen-equivalent taxa. Estimated vegetation is correlated in the same area with a human activity model based on all available archaeological information and a macrophysical climate model. The palaeovegetation record indicates the continuous presence of open land throughout the Holocene. Grasslands and open woodlands were probably maintained by local arid climatic conditions during the early Holocene delaying the spread of deciduous (oak) forests. Significantly detectable human-made landscape transformation started only after 2000 BC. Our analyses suggest that Neolithic people spread into a landscape that was already open. Humans probably contributed to the spread of oak, and influenced the dynamics of hazel and hornbeam.

10.
J Exp Bot ; 65(8): 2137-46, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24642846

RESUMEN

The proper timing of flowering is essential for the adaptation of plant species to their ever-changing environments. The central position in a complex regulatory network is occupied by the protein FT, which acts as a florigen. We found that light, following a permissive period of darkness, was essential to induce the floral promoter CrFTL1 and to initiate flowering in seedlings of the short-day plant Chenopodium rubrum L. We also identified two novel CONSTANS-like genes in C. rubrum and observed their rhythmic diurnal and circadian expressions. Strong rhythmicity of expression suggested that the two genes might have been involved in the regulation of photoperiod-dependent processes, despite their inability to complement co mutation in A. thaliana. The CrCOL1 and CrCOL2 genes were downregulated by dark-light transition, regardless of the length of a preceding dark period. The same treatment activated the floral promoter CrFTL1. Light therefore affected CrCOL and CrFTL1 in an opposite manner. Both CrCOL genes and CrFTL1 displayed expression patterns unique among short-day plants. Chenopodium rubrum, the subject of classical physiological studies in the past, is emerging as a useful model for the investigation of flowering at the molecular level.


Asunto(s)
Chenopodium/fisiología , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Secuencia de Aminoácidos , Arabidopsis , Chenopodium/genética , Chenopodium/crecimiento & desarrollo , Florigena/metabolismo , Flores/crecimiento & desarrollo , Prueba de Complementación Genética , Fotoperiodo , Proteínas de Plantas/metabolismo , Regiones Promotoras Genéticas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Plantones/crecimiento & desarrollo , Alineación de Secuencia
11.
Sheng Wu Gong Cheng Xue Bao ; 25(7): 1014-21, 2009 Jul.
Artículo en Chino | MEDLINE | ID: mdl-19835142

RESUMEN

Arylalkylamine N-acetyltransferase (AANAT) and Hydroxyindole O-methyltransferase(HIOMT) are the key regulation enzymes in the melatonin biosynthesis pathway in mammals. The AANAT and HIOMT genes were constructed into a binary plant expression vector YXu55. Using leaf strips as the recipiences, we efficiently transformed tobacco (Nicotiana tabacum) variety qinyan 95 by the Agrobacterium mediated method. After gradient selection with gentamycin, a number of transgenic plants were regenerated. Southern blot and RT-PCR analyses showed that the AANAT-HIOMT genes were integrated into the genome of the transgenic plants and the target genes could express at the level of RNA transcription. By RP-HPLC, we measured the melatonin contents in transgenic plants. The results showed that the melatonin level in YXu55 (containing the gentamycin-resistance gene, the AANAT gene and HIOMT gene) transgenic plants were much higher than those in pZP122 (control containing only the gentamycin-resistance gene) transgenic plants and nontransgenic plants. The content of melatonin in pZP122 transgenic plants was nearly the same as that in nontransgenic plants. Physiological determination of antioxidative characteristics demonstrated that 1) the capacity of total antioxidation, 2) the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) and 3) the content of glutathione (GSH) were increased in YXu55 transgenic plants containing the AANAT-HIOMT genes as compared to the control plants (pZP122 or nontransgenic plants). At the same time, malonaldehyde (MDA) content did not appear remarkably difference between transgenic plants and nontransgenic plants. The above mentioned facts indicate enhancement of melatonin levels in YXu55 transgenic plants might help to reduce damage by oxidative stress.


Asunto(s)
Agrobacterium tumefaciens/genética , N-Acetiltransferasa de Arilalquilamina/genética , Melatonina/biosíntesis , Nicotiana/genética , Transducción Genética/métodos , Acetilserotonina O-Metiltransferasa/genética , Catalasa/metabolismo , Regulación Enzimológica de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Peroxidasa/metabolismo , Plantas Modificadas Genéticamente/enzimología , Plantas Modificadas Genéticamente/genética , Superóxido Dismutasa/metabolismo , Nicotiana/enzimología
12.
Planta ; 228(6): 929-40, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18654796

RESUMEN

FLOWERING LOCUS T (FT) like genes are crucial regulators (both positive and negative) of flowering in angiosperms. We identified two FT homologs in Chenopodium rubrum, a short-day species used as a model plant for the studies of photoperiodic flower induction. We found that CrFTL1 gene was highly inducible by a 12-h dark period, which in turn induced flowering. On the other hand, photoperiodic treatments that did not induce flowering (short dark periods, or a permissive darkness interrupted by a night break) caused only a slight increase in CrFTL1 mRNA level. We demonstrated diurnal oscillation of CrFTL1 expression with peaks in the middle of a light period. The oscillation persisted under constant darkness. Unlike FT homologs in rice and Pharbitis, the CrFTL1 expression under constant darkness was very low. The CrFTL2 gene showed constitutive expression. We suggest that the CrFTL1 gene may play a role as a floral regulator, but the function of CrFTL2 remains unknown.


Asunto(s)
Chenopodium/metabolismo , Proteínas de Plantas/metabolismo , Secuencia de Aminoácidos , Chenopodium/genética , Chenopodium/crecimiento & desarrollo , Chenopodium/efectos de la radiación , Ritmo Circadiano , ADN Complementario/química , Oscuridad , Flores/genética , Flores/crecimiento & desarrollo , Flores/metabolismo , Flores/efectos de la radiación , Regulación de la Expresión Génica de las Plantas/efectos de la radiación , Datos de Secuencia Molecular , Fotoperiodo , Proteínas de Plantas/química , Proteínas de Plantas/genética , ARN Mensajero/metabolismo , Alineación de Secuencia
13.
J Plant Physiol ; 165(15): 1601-9, 2008 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-18308426

RESUMEN

The time of flowering is regulated by various environmental cues, and in some plant species, it is known to be affected by abiotic stresses. We investigated the effect of nutrient stress caused by an abrupt reduction of mineral nutrition on flowering of Arabidopsis thaliana. We used a hydroponic culture system that enabled us to precisely control nutrient levels. When plants were grown in full-strength nutrient solution for several weeks and then transferred to a diluted medium, the time from sowing to bud appearance was significantly shortened. This acceleration of flowering was more pronounced in short days than in long days, and stronger in the ecotype Landsberg erecta than in Columbia and San Feliu-2. The response was also affected by the age of plants at the beginning of nutrient stress and by the concentration of the diluted medium: earlier treatment and more diluted solutions strengthened the effect. Flowering was affected by nutrient stress, not by a change in the osmotic potential of the medium: addition of mannitol to a 1000-fold diluted solution had no effect on the promotion of flowering. When 3-week-old Landsberg erecta plants were exposed to 1000-fold diluted nutrient solution in an 8-h day length, flower bud appearance was strongly and reproducibly advanced by 10.8-12.8d compared with control plants (which developed buds 41.1-46.2d after sowing). This treatment can serve as an optimized protocol for future studies concerning physiological, molecular and ecological aspects of flower induction by nutrient stress in A. thaliana.


Asunto(s)
Arabidopsis/fisiología , Flores/crecimiento & desarrollo , Minerales/metabolismo , Arabidopsis/genética , Genotipo , Hidroponía , Concentración Osmolar
14.
J Pineal Res ; 39(4): 333-41, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16207287

RESUMEN

Melatonin may be ubiquitous in the plant kingdom. This review considers the evaluation of methods of melatonin determination in plant material and possible melatonin functions in plants. Concerning the determination methods, the only reliable techniques are liquid chromatography--mass spectrometry or gas chromatography--mass spectrometry after some purification steps of the extract. Melatonin was shown to delay flower induction in some photoperiodic plants and in the dinoflagellate Lingulodinium it replaces, in part, the requirement of darkness for cyst formation. Melatonin may also have a function as an antioxidant and it may possess some auxin-like effects. Finally, it may act as a signal for interaction of plants with herbivores and pests. Further research is needed to clarify these potential functions.


Asunto(s)
Melatonina/fisiología , Plantas/metabolismo , Animales , Antioxidantes , Cromatografía Liquida , Ritmo Circadiano/efectos de los fármacos , Dinoflagelados/química , Cromatografía de Gases y Espectrometría de Masas , Melatonina/análisis , Fotoperiodo , Reguladores del Crecimiento de las Plantas , Plantas/química
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