Mesomelic form of chondrodysplasia and congenital glaucoma associated with de novo translocation (13;18)(q14;q23)

Mesomelic form of chondrodysplasia and congenital glaucoma associated with de novo translocation (13;18)(q14:q23): Mesomelic dysplasias are characterized by limb shortening most prominent of the middle segment of the extremities (forearm and lower leg). In addition to several syndromic forms a few patients with sporadic or familial forms and without precise nosological classification have been reported so far. In this report we present a young female with disproportionate mesomelic dwarfism, dysmorphic facial features, bilateral glaucoma, patent ductus arteriosus, low and hoarse voice, and generalized muscular hypotonia. At the age of 2.5 years mental development is normal. High resolution G-banded chromosome studies revealed a de novo reciprocal translocation with karyotype 46,XX t (13;18)(q14;q23). The concurrence of this de novo autosomal translocation with this distinct phenotype supports the hypothesis that disruption of (a) gene(s) at the translocation breakpoints causes this unusual, apparently new form of skeletal chondrodysplasia.     

Cell biology of virus entry: a review of selected topics from the 3rd International Frederick meeting

Following the first two Frederick meetings on virus entry in 1997 [Cell 91 (1997) 721](1) and in 2000 [Cell 101 (2000) 697](2), further developments in our understanding of the multifactorial and multistage process of virus entry, and possible biomedical implications were presented and discussed in a lively fashion by leading scientists from around the world at the third Frederick meeting on the Cell Biology of Viral Entry (May 7-10, Frederick, MD) organized by R. Blumenthal (NCI-Frederick, NIH, Frederick) and E. Hunter (University of Alabama, Birmingham). Unlike the previous two meetings, non-enveloped viruses were not discussed this time, and the focus was how envelope glycoproteins (Envs) mediate entry into cells. Major topics included Env structure, virus receptors, entry intermediates, membrane fusion, fusion kinetics, and rafts. Virus envelope structures will be described in more detail here because the other topics are extensively discussed in the other chapters of this volume.     

The SARS-CoV S glycoprotein: expression and functional characterization

We have cloned, expressed, and characterized the full-length and various soluble fragments of the SARS-CoV (Tor2 isolate) S glycoprotein. Cells expressing S fused with receptor-expressing cells at neutral pH suggesting that the recombinant glycoprotein is functional, its membrane fusogenic activity does not require other viral proteins, and that low pH is not required for triggering membrane fusion; fusion was not observed at low receptor concentrations. S and its soluble ectodomain, S(e), were not cleaved to any significant degree. They ran at about 180-200kDa in SDS gels suggesting post-translational modifications as predicted by previous computer analysis and observed for other coronaviruses. Fragments containing the N-terminal amino acid residues 17-537 and 272-537 but not 17-276 bound specifically to Vero E6 cells and purified soluble receptor, ACE2, recently identified by M. Farzan and co-workers [Nature 426 (2003) 450-454]. Together with data for inhibition of binding by antibodies developed against peptides from S, these findings suggest that the receptor-binding domain is located between amino acid residues 303 and 537. These results also confirm that ACE2 is a functional receptor for the SARS virus and may help in the elucidation of the mechanisms of SARS-CoV entry and in the development of vaccine immunogens and entry inhibitors.     

Cancer cell dynamics in presence of telomerase inhibitors: analysis of in vitro data

The inhibition of telomerase activity in actively dividing cells leads to suppression of cell growth after a time delay (inhibitory delay) required to reach a threshold telomeric DNA size. We developed a mathematical model of the dynamics of telomere size distribution and cell growth in the presence of telomere inhibitors that allowed quantification of the inhibitory delay. The model based on the solution of a system of differential equations described quantitatively recent experimental data on dynamics of cultured cells in presence of telomerase inhibitors. The analysis of the data by this model suggested the existence of at least two distinct subpopulations of cells with different proliferative activity. Size distribution of telomeres, fraction of proliferating cells, and tumor doubling times are of critical importance for the dynamics of cancer cells growth in presence of telomerase inhibitors. Rapidly growing cells with large telomeric DNA heterogeneity and small proliferating fractions as well as those with very short homogeneous telomeres would be the most sensitive to telomerase inhibitors.     

Two new sulfated furostanol saponins from Tribulus terrestris

The known furostanol saponins methylprotodioscin and protodioscin and two new sulfated saponins, sodium salt of 26-O-beta-glucopyranosyl-22alpha-methoxy-(25R)-furost-5-ene-3beta,26-diol-3-O-alpha-rhamnopyranosyl-(1-->2)-beta-4-O-sulfo-glucopyranoside (methylprototribestin) and sodium salt of 26-O-beta-glucopyranosyl-22alpha-hydroxy-(25R)-furost-5-ene-3beta,26-diol-3-O-alpha-rhamnopyranosyl-(1-->2)-beta-4-O-sulfo-glucopyranoside (prototribestin) have been isolated from the aerial parts of Tribulus terrestris L. growing in Bulgaria. The structures of the new compounds were elucidated on the basis of 1D and 2D (DQF-COSY, TOCSY, HSQC-TOCSY, HSQC, HMBC, ROESY) NMR data, ESI mass spectra and chemical transformation.     

Phyllobothrium squali Yamaguti, 1952 (Tetraphyllidea,Phyllobothriidae): redescription and first record in the Black Sea

Phyllobothrium squali Yamaguti, 1952 is redescribed and illustrated on the basis of the holotype from Squalus acanthias from Japanese waters and specimens from the same host off the Bulgarian Black Sea coast (new geographical record). The species is characterised by: a scolex diameter of 2.9-4.3 mm, a glandular apical organ, foliose bothridia with folded and posteriorly bifid margins, accessory suckers of 286-367 micro m in diameter, 222-373 testes per proglottis, an oval cirrus-sac with a length of 354-655 micro m, the vagina opening anteriorly to the cirrus-sac, and the terminal part of vagina with a circular musculature. Specimens from Etmopterus spinax off Naples, Mediterranean Sea, recorded by Euzet (1959) as Crossobothrium squali, are redescribed and their identification not confirmed. P. squali is recognised as a specific parasite of S. acanthias; it is presently known only from Japanese waters, the Black Sea and the Irish Sea. Changes to the generic diagnosis of Phyllobothrium, as given by Ruhnke (1996a), are proposed in order to include the characters of P. squali.     

Variability in the taxonomic characters of Black Sea gyrodactylids (Monogenea)

Variability of the haptoral hard parts of four Black Sea Gyrodactylus species (G. alviga Dmitrieva & Gerasev, 2000; G. crenilabri Zaika, 1966; G. flesi Malmberg, 1957; G. sphinx Dmitrieva & Gerasev, 2000) was studied in relation to season, host and geographical variability. A discriminant analysis was carried out on the measurements of 14 characters of the haptor of all four species. The haptoral hard parts of the investigated gyrodactylids decrease in size with an increase in water temperature. It is known that life-span of gyrodactylids is negatively correlated with water temperature and they exhibit peak intensities at low temperature. At the same time, life-span is considered to be a general indicator of a favourable environment. Therefore, high water temperature is not apparently advantageous for gyrodactylids. In the case of low marine salinity, in adapted species the sizes of the haptoral hard parts are larger at lower levels of salinity and vice versa for typical marine species. Lastly, in specimens parasitising the primary host, these features are larger than in those parasitising a secondary host. It is possible to say that, in general, the more favourable the environment for gyrodactylids the larger their haptoral hard parts. Unfavourable environmental conditions reduce the time of embryogenesis, which has a dual effect on gyrodactylids: positive in relation to their reproduction (by increasing the reproduction rate) and negative in relation to their development (by decreasing the size of the haptoral hard parts).     

Changes of the power coefficient in the 'metabolism-mass' relationship in the evolutionary process of animals

The power coefficient k decreases along evolution in an allometric relationship between the oxygen consumption rate and the body mass of animals. This theoretical study investigated the role of the power coefficient k and its behavior along evolution. The animals were organized in three groups according to the values of the power coefficient k as follows: (I) from unicellular Prokaryotes to Eukaryotes; (II) from Mytilus and Annelida to Pisces; (III) from Reptilia to Mammals and Aves. At the beginning of each animal group (stage), the value of k was close to 0.9-1.0 and at the end of the stage it was close to 0.67-0.70. Exponential sharp increase of the power coefficient k was observed during the biological transition from Protozoa to simply organized Metazoa and in the transition from Poikylothermic to Homothermic organisms (e.g. from Pisces to Reptilia). Also, when using the periodogram regression analysis, a cyclic (periodic) pattern in this increase was observed (i.e. period T approximately 8-11 units, P<0.05). It was postulated that the power coefficient k, as with the coefficient a, might represent the increase of complexity of animal organization within each group.     

Argentophilic structures of miracidia and cercariae of Philophthalmus lucipetus (Philophthalmidae: Trematoda) from Israel

Argentophilic structures of Philophthalmus lucipetus miracidia and cercariae from Israel are described. Eighty-four of 87 miracidia examined displayed an epidermal plate arrangement of 6:8:4:2 = 20, similar to other Philophthalmus species. Twenty papilla-like structures are arranged on the terebratorium in 3 groups, along 1 axis. Sixteen body papillae are located at the bases of epidermal plates of row 1. Eyespots are mediodorsal, between rows 1 and 2. Excretory pores are lateral, between rows 2 and 3. Features common to Israeli and Bulgarian isolates, differentiating them from other species, include the presence of 16 body papillae as opposed to 10 in other species, and a maximum of 20 papillae on the terebratorium as opposed to 19 in the others. About 3% of the miracidia displayed different plate arrangements. Among the argentophilic structures of P. lucipetus cercariae, the Israeli and Bulgarian P. lucipetus show a common pattern of 2-4 excretory pores in the tail, but arrangement of cephalic CI3 and CI5 papillae in the 2 isolates is insufficiently unequivocal for species determination. The data presented show that miracidial characteristics, rather than those of cercariae, aid in determining the species of philophthalmids. They also support former evidence attesting to the identity of the Bulgarian and Israeli species.     

Argentophilic structures of the miracidia and cercariae of Philophthalmus distomatosa n. comb. from Israel

The morphology and patterns of distribution of the argentophilic structures of miracidia and cercariae of Philophthalmus distomatosa n. comb. are described. The epidermal plate arrangement of the vast majority (94.2%) of miracidia studied conformed to the formula 6:8:4:2 = 20. The rest (5.8%) displayed the following patterns of arrangement of epidermal plates: 6:7:4:2 = 19; 6:6:4:2 = 18; and 6:4:4:2 = 16. Twenty papillalike structures were observed on the terebratorium. They were arranged along 1 axis, in 3 groups. Most commonly, 16 papillae were present on the body, located between epidermal plates of the first and second rows. The eye spots were located dorsally, near interepidermal space S1. The numbers, arrangements, and locations of the excretory pores varied. Patterns of distribution of the tegumentary papillae of P. distomatosa n. comb. cercariae are given, including those of the cephalic regions, periacetabular region, and tail. Argentophilic structures of the mentioned larval stages and of other parameters clearly distinguishing between the presently described species and those of P. lucipetus from Israel are summarized. On the basis of comparison of the presently described larval stages and those of other Melanoides tuberculata-associated larval stages of Philophthalmus in Israel and Jordan, the possibility exists that a third species occurs in Israel.