Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Ancient Lands”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

A conserved transcription factor mediates nuclear control of organelle biogenesis in anciently diverged land plants.

Land plant chloroplasts evolved from those found in the green algae. During land plant evolution, nuclear regulatory mechanisms have been modified to produce morphologically and functionally diverse chloroplasts in distinct developmental contexts. At least some of these mechanisms evolved independently in different plant lineages. In angiosperms, GOLDEN2-LIKE (GLK) transcription factors regulate the development of at least three chloroplast types. To determine whether GLK-mediated regulation of chloroplast development evolved within angiosperms or is a plesiomorphy within land plants, gene function was examined in the moss Physcomitrella patens. Gene expression patterns and loss-of-function mutant phenotypes suggested that GLK gene function is conserved between P. patens and Arabidopsis thaliana, species that diverged >400 million years ago. In support of this suggestion, moss genes partially complement Arabidopsis loss-of-function mutants. Therefore, GLK-mediated regulation of chloroplast development defines one of the most ancient conserved regulatory mechanisms identified in the plant kingdom.

Arabidopsis↗

Caribbean biogeography: molecular evidence for dispersal in West Indian terrestrial vertebrates.

The geological association of the Greater Antilles with North and South America in the late Cretaceous led to the hypothesis that the present Antillean biota reflects those ancient land connections. Molecular data from diverse West Indian amphibians and reptiles and their mainland relatives support a more recent derivation of the Antillean vertebrate fauna by overwater dispersal. The catastrophic bolide impact in the Caribbean region at the close of the Cretaceous provides a proximate cause for the absence of an ancient West Indian biota.

Journal Article↗

Moss transcriptome and beyond.

The ancient land plant Physcomitrella patens is a model system that is becoming increasingly important for plant functional genomics because gene knockouts can be produced with relative ease. Recently, several EST-sequencing projects have been launched as a first step towards a thorough functional characterization of the moss. However, for careful comparison with other plant model systems, the complete genomic sequence is needed as well as the transcriptome.

Arabidopsis↗

Experiences in a war zone.

War surgery presents a different set of problems to those encountered in the conventional surgery. I was fortunate enough to travel to Afghanistan, under the auspices of the International Committee of the Red Cross, and participate in such surgery. This article describes my experiences in this ancient land.

Afghanistan↗

The monosaccharide transporter gene family in land plants is ancient and shows differential subfamily expression and expansion across lineages.

BACKGROUND: In plants, tandem, segmental and whole-genome duplications are prevalent, resulting in large numbers of duplicate loci. Recent studies suggest that duplicate genes diverge predominantly through the partitioning of expression and that breadth of gene expression is related to the rate of gene duplication and protein sequence evolution.Here, we utilize expressed sequence tag (EST) data to study gene duplication and expression patterns in the monosaccharide transporter (MST) gene family across the land plants. In Arabidopsis, there are 53 MST genes that form seven distinct subfamilies. We created profile hidden Markov models of each subfamily and searched EST databases representing diverse land plant lineages to address the following questions: 1) Are homologs of each Arabidopsis subfamily present in the earliest land plants? 2) Do expression patterns among subfamilies and individual genes within subfamilies differ across lineages? 3) Has gene duplication within each lineage resulted in lineage-specific expansion patterns? We also looked for correlations between relative EST database representation in Arabidopsis and similarity to orthologs in early lineages. RESULTS: Homologs of all seven MST subfamilies were present in land plants at least 400 million years ago. Subfamily expression levels vary across lineages with greater relative expression of the STP, ERD6-like, INT and PLT subfamilies in the vascular plants. In the large EST databases of the moss, gymnosperm, monocot and eudicot lineages, EST contig construction reveals that MST subfamilies have experienced lineage-specific expansions. Large subfamily expansions appear to be due to multiple gene duplications arising from single ancestral genes. In Arabidopsis, one or a few genes within most subfamilies have much higher EST database representation than others. Most highly represented (broadly expressed) genes in Arabidopsis have best match orthologs in early divergent lineages. CONCLUSION: The seven subfamilies of the Arabidopsis MST gene family are ancient in land plants and show differential subfamily expression and lineage-specific subfamily expansions. Patterns of gene expression in Arabidopsis and correlation of highly represented genes with best match homologs in early lineages suggests that broadly expressed genes are often highly conserved, and that most genes have more limited expression.

Arabidopsis↗

Mold: "tsara'at," Leviticus, and the history of a confusion.

The noun tsara'at appears about two dozen times in the Hebrew Bible, almost exclusively in Leviticus, where it is used to describe a state of ritual defilement manifested as a scaly condition of the skin, a condition of cloth, leather, and the walls of houses. In the Septuagint, the Greek translation of the Hebrew Bible, negac tsara'at was translated as aphe lepras; in the Latin Vulgate, this became plega leprae. These words in Greek and Latin implied a condition that spread over the body, not a term of ritual impurity. Tsara'at has continued to be translated as "leprosy," even though this term is not appropriate, as there was no leprosy as we know it in the Middle East during the time period the Hebrew Bible was written. Others have suggested that the proper translation of tsara'at is "mold." The recent identification of a specific mold (Stachybotrys sp.) that contaminates buildings and causes respiratory distress, memory loss, and rash, and the fact that mold has been present for millennia, lend support to the translation of tsara'at as "mold."

Ancient Lands↗

The rules of drug taking: wine and poppy derivatives in the Ancient World. VIII. Lack of evidence of opium addiction.

The widespread therapeutic use of opium and its probable ritual use is faced with the absence of any explicit description of cases of opium dependence. It is possible that this was due to a lack of diagnostic capability. However, even the attempt to uncover cases of opium dependence by systematically analyzing the literary passages in which poppies, opium, and meconium are quoted are unsuccessful. The only two cases of suspected opium addiction that can be selected in this way are those of the Emperor Marcus Aurelius and Ovid. The most parsimonious interpretation is the lack of an hedonic use of poppy derivatives, being that this kind of use is the most frequently connected with the development of addiction.

Ancient Lands↗

"At times these ancient facts seem to lie before me like a patient on a hospital bed'--retrospective diagnosis and ancient medical history.

Research in ancient medical history, Greek and Roman as well as Mesopotamian and Egyptian, is usually done by philologically trained scholars; the ability to read texts in their original language is fundamental (though not sufficient) for any substantial work. There is, however, in such works the notion that something may be missing in fully understanding medicine of a certain time and culture. Does a medical historian of ancient medicine need, in addition to his philological and historical skills, a medical education? And in what way is a 'medical approach' to ancient medicine useful? Is it possible to stand at the bedside of a Hippocratic patient as a clinician or reconstruct the 'pathocoenosis', as Mirko D. Grmek (+ 2000) coined it, of ancient Greece? The present paper outlines the problem of applying present medical knowledge to ancient sources and touches on the topic of primary perception of disease and illness. An important aspect is that disease entities change in their socio-cultural setting. Examples ranging from the supposed Lupus erythematodes of the Assyrian king Esarhaddon to cases in the Hippocratic Epidemiae and plague descriptions of Greek authors illustrate the problem of retrospective diagnosis.

Ancient Lands↗