Structural Integrity of the Greek Key Motif in beta gamma-Crystallins Is Vital for Central Eye Lens Transparency

Background: We highlight an unrecognized physiological role for the Greek key motif, an evolutionarily conserved super-secondary structural topology of the beta gamma-crystallins. These proteins constitute the bulk of the human eye lens, packed at very high concentrations in a compact, globular, short-range order, generating transparency. Congenital cataract (affecting 400,000 newborns yearly worldwide), associated with 54 mutations in beta gamma-crystallins, occurs in two major phenotypes nuclear cataract, which blocks the central visual axis, hampering the development of the growing eye and demanding earliest intervention, and the milder peripheral progressive cataract where surgery can wait. In order to understand this phenotypic dichotomy at the molecular level, we have studied the structural and aggregation features of representative mutations. Methods: Wild type and several representative mutant proteins were cloned, expressed and purified and their secondary and tertiary structural details, as well as structural stability, were compared in solution, using spectroscopy. Their tendencies to aggregate in vitro and in cellulo were also compared. In addition, we analyzed their structural differences by molecular modeling in silico. Results: Based on their properties, mutants are seen to fall into two classes. Mutants A36P, L45PL54P, R140X, and G165fs display lowered solubility and structural stability, expose several buried residues to the surface, aggregate in vitro and in cellulo, and disturb/distort the Greek key motif. And they are associated with nuclear cataract. In contrast, mutants P24T and R77S, associated with peripheral cataract, behave quite similar to the wild type molecule, and do not affect the Greek key topology. Conclusion: When a mutation distorts even one of the four Greek key motifs, the protein readily self-aggregates and precipitates, consistent with the phenotype of nuclear cataract, while mutations not affecting the motif display `native state aggregation', leading to peripheral cataract, thus offering a protein structural rationale for the cataract phenotypic dichotomy ``distort motif, lose central vision''.

‘Neptune’ between ‘Hesperus’ and ‘Vulcan’: On descriptive names and non-existence

[EN]This work will focus on some aspects of descriptive names. The New Theory of Reference, in line with Kripke, takes descriptive names to be proper names. I will argue in this paper that descriptive names and certain theory in reference to them, even when it disagrees with the New Theory of Reference, can shed light on our understanding of (some) non-existence statements. I define the concept of descriptive name for hypothesised object (DNHO). My thesis being that DNHOs are, as I will specify, descriptions: a proposition expressed by the utterance ‘n is F’, where ‘n’ is a DNHO, is not singular at all; it is a descriptive proposition. To sum up, concerning proper names, the truth lies closer to the New Theory of Reference, but descriptivism is not altogether false. As for DNHOs descriptivism is, in some cases, the right fit.

Multilingual Nomenclature of Place and Oceanographic Names in the Region of the Okhotsk Sea

clarify the multilingual problem of place and oceanographic names in the region of the Okhotsk Sea, especially in Southern Sakhalin (Minami Karafuto) and in the Kuril Islands (Chishima Islands) areas. (PDF contains 61 pages)

Algunos nombres de vinos en griego antiguo

[ES]La frecuente presencia del vino en la literatura griega antigua pone de relieve su importancia como elemento de cultura. En general, sus nombres hacen referencia directa al lugar de procedencia, pero junto a ellos hay otros de origen poco claro o a los que se ha prestado poca atención y que pueden ser importantes para ampliar nuestros conocimientos sobre esta bebida.

Space and Gender in the Ancient Greek Novel

The plots of the five Greek novels of "love and Adventures" are set in two differentent spaces. First, a macrospace, a gigantic stage which mainly includes Eastern cities of the Roman Empire, where the protagonists live the so-called adventures. And second, the microspaces, depicted in Longus' novel and occasionally in the other novels. The love ideology is clearly conservative, and it has a specific practical purpose among the Hellenized higher classes in the Eastern Empire.

Updating names, distribution and ecology of riverine fish of Kenya in the Athi-Galana-Sabaki river drainage system

Few studies of the riverine fish of the Athi-Galana-Sabaki river drainage area in Kenya have been carried out since the last comprehensive surveys of the 1950s and early 1960s. This paper presents updated information on scientific and recommended common names, distribution and ecology of selected fish species of this catchment. At least 28 riverine fish families consisting of 46 genera and 62 species occur in the drainage system, of which, 39 species are strictly freshwater (4 introduced) while 23 species are of marine origin. Five unique behavioural categories of the riverine fish of the drainage system are discussed. The four most speciated riverine fish in the system belong to the families Cyprinidae (14 species), Cichlidae (6 species), and Mormyridae and Gobiidae (4 species each). Thirty fish species occur in areas below the River Tsavo-Athi confluence, 18 fish species above the confluence, while 12 fish species occupy the entire drainage system. One cichlid fish, Oreochromis spilurus spilurus (Gunther, 1894), only occurs in the Tsavo river, while the occurrence in the entire system of one snoutfish species, Mormyprops anguilloides (Linnaeus, 1758) is uncertain. The use of information from this study is recommended when carrying out further studies of fish from the Athi-Galana-Sabaki river drainage.

A review of length-weight relationships of fishes from Greek marine waters

This paper presents 649 length-weight relationships gathered from literature pertaining to 83 fish species, belonging to 34 families, throughout Greek marine waters. The value of the slope b ranged from 1.667 for Cepola macrophthalma to 3.707 for Mullus barbatus. The mean value of b was 2.989 (SD=0.339) and did not differ significantly from 3(t-test, p<0.05). The median value of b was 3.058 and 50% of the b values ranged between 2.900 and 3.186.

Biological parameters, body length-weight and length-height relationships for various species in Greek waters

Biological/fisheries parameters (L sub(oo) M, F) are presented for four fish species (Gadiculus argenteus; Gaidropsarus mediterraneous; Symphurus ligulatus; Lepidorhombus boscii) as well as body length-weight and length-height relationships for 11 and 12 fish species, respectively, estimated from trawl samples collected using three different cod-ends (stretched mesh size: 14 mm and 20 mm diamond-shaped and 20 mm square-shaped) during 1993-1994, in the western Aegean and North Euboikos Gulf, Greece. The fisheries paramaters, estimated from length-frequency using the ELEFAN approach and software, are discussed in the light of recent information on the selectivity of the presently used trawl cod-end (14 mm diamond shaped)

Problems with Unofficial and Inaccurate Geographical Names in the Fisheries Literature

Over a century of fi shery and oceanographic research conducted along the Atlantic coast of the United States has resulted in many publications using unofficial, and therefore unclear, geographic names for certain study areas. Such improper usage, besides being unscholarly, has and can lead to identification problems for readers unfamiliar with the area. Even worse, the use of electronic data bases and search engines can provide incomplete or confusing references when improper wording is used. The two terms used improperly most often are “Middle Atlantic Bight” and “South Atlantic Bight.” In general, the term “Middle Atlantic Bight” usually refers to an imprecise coastal area off the middle Atlantic states of New York, New Jersey, Delaware, Maryland, and Virginia, and the term “South Atlantic Bight” refers to the area off the southeastern states of North Carolina, South Carolina, Georgia, and Florida’s east coast.