Parental care in the rocky intertidal: a case study of adaptation and exaptation in Mediterranean and Atlantic blennies

Summary The main features of the behavioural ecology of rocky intertidal species are compared both within families — though concentrated on blennies — and between habitats. It is suggested that, at the behavioural level, the reduction of vertical and swimming elements in the male sexual and agonistic displays of Blennioidei may constitute an adaptation to typical intertidal conditions, especially in those species that inhabit areas exposed to strong wave action. The other aspect which is discussed is the prevalence of parental care in rocky intertidal fishes. In these fishes parental care is much more frequent than for marine fishes as a whole. Taken alone, this could also suggest that guarding evolved as an adaptation during the process of colonization of these habitats. The hypothesis proposed in this paper is that guarding was already present in the ancestors of the resident species, at least in the majority of cases. Many differences in interhabitat studies may express the action of the environment, not as an agent of natural selection, but as a filter, which prevented some groups from invading a given habitat and, at the same time, made colonization easier for other groups. When a number of taxa that colonized a given habitat display clear similarities in their behaviour and their biology, adaptation is not necessarily demonstrated. There is evidence in the literature to support the hypothesis that those traits were already present in the ancestors of the rocky intertidal resident fishes, thus being best viewed as exaptations.     

The larval midgut of the cassava hornworm (Erinnyis ello)

Summary Columnar cells of the larval midgut of the cassava hornworm, Erinnyis ello, display microvilli with vesicles pinching off from their tips (anterior and middle midgut) or with a large number of double membrane spheres budding along their length (posterior midgut). Basal infoldings in columnar cells occur in a parallel array with many openings to the underlying space (posterior midgut) or are less organized with few openings (anterior and middle midgut). Goblet cells have a cavity, which is formed by invagination of the apical membrane and which occupies most of the cell (anterior and middle midgut) or only its upper part (posterior midgut). The infolded apical membrane shows modified microvilli, which sometimes (posterior midgut) or always (anterior and middle midgut) contain mitochondria. The cytoplasmic side of the membrane of the microvilli that contain mitochondria are studded with small particles. The results suggest that the anterior and middle region of the midgut absorbs water, whereas the posterior region secretes it. This results in a countercurrent flux of fluid, which is responsible for the enzyme recovery from undigested food before it is expelled. Intermediary and final digestion of food probably occur in the columnar cells under the action of plasma membrane-bound and glycocalix-associated enzymes.     

Bone marrow transplantation: current results in leukemia

Bone marrow transplantation offers two potential therapeutic advantages over more conventional therapy of leukemia. It allows more intensive treatment to be given without regard to marrow toxicity and allows in the case of allogeneic marrow an additional immunotherapeutic effect through graft-versus-host disease (GVHD). Initially, allogeneic transplants in HLA matched sibling donors were only employed in end-stage patients. Although there were encouraging results in terms of long-term therapeutic effects, the overall mortality was prohibitive. Subsequently, patients were transplanted in remission with a marked improvement in overall survival in both acute lymphocytic leukemia and acute non-lymphocytic leukemia. The major obstacles to further improvement in the therapeutic effects of this procedure have been identified (i.e., GVHD, viral infection, and relapse in ALL) and are subject to intensive investigations that already show encouraging results. Syngeneic marrow transplantation is limited for obvious reasons, but early results have shown significant therapeutic effects, in particular, in chronic myelogenous leukemia. These results have encouraged others to use autologous bone marrow. Marrow contamination with unseen tumor cells is being approached by pharmacologic and immunologic techniques designed to "purge" marrow of tumor cells. Animal and initial clinical studies have been encouraging.     

Dihydroisocoumarins and phthalide from wood samples infested by fungi

Wood samples, infested by fungi during storage, were shown to contain, besides the known 5-methyl-mellein, additional (3R)-8-hydroxy-3-methyl-3,4-dihydroisocoumarins substituted by 7-methyl, 5-formyl, 5-carboxy, 5-hydroxy, 5-methoxy, 6-methoxy-5-methyl and 6,7-dimethoxy-5-methyl groups, as well as 6-formyl-7-hydroxy-5-methoxy-4-methylphthalide. Several 2-methylchromanones were synthesized in order to show that this class of compounds can be distinguished from 3-methyl-3,4-dihydroisocoumarins by MS.     

The phosphorus efficiency of three annual legumes

Summary Trifolium subterraneum, Trifolium glomeratum andOrnithopus compressus were grown in soil and solution culture at varying P concentrations. Efficiency of P utilization was determined using the following criteria: (1) The ability to produce tops dry matter with a given amount of applied P, (2) Tops dry matter produced per unit of P taken up, (3) Tops dry matter produced at a constant plant P level and (4) Phosphorus uptake per unit root weight. The order of efficiency varied according to the crieteria used. Using the agronomic definition (1), Serradella was the most efficient species at 70 days. The need to clearly define what is meant by an efficient species is demonstrated.     

B-chromosome polymorphism and interchromosomal chiasma interference in Eyprepocnemis plorans (Acrididae; Orthoptera)

Using the C-banding technique, the morphology and meiotic behaviour of four different types of B-chromosomes present in several populations of Eyprepocnemis plorans have been studied. The possible relationship between these four types is discussed. The analysis of chiasma frequency in A and B-chromosomes suggests the existence of interchromosomal interference and demonstrates that the chiasma frequency of B-s depends on the genetic background of the individual carrying them.     

NMR redox studies of Desulfovibrio vulgaris Cytochrome c3. Electron transfer mechanisms

The 300-MHz proton NMR spectra of the tetrahaem cytochrome c3 from Desulfovibrio vulgaris were examined while varying the pH and the redox potential. The analysis of the complete NMR reoxidation pattern was done taking into account all the 16 redox states that can be present in the redox titration of a tetra-redox-center molecule. A network of saturation transfer experiments performed at different oxidation stages, between the fully reduced and the fully oxidized states, allowed the observation of different resonances for some of the haem methyl groups. In the present experimental conditions, some of the haems show a fast intramolecular electron exchange rate, but the intermolecular electron exchange is always slow. In intermediate reoxidation stages, large shifts of the resonances of some haem methyl groups were observed upon changing the pH. These shifts are discussed in terms of a pH dependence of the haem midpoint redox potentials. The physiological relevance of this pH dependence is discussed.     

Lysis of human keratinocytes by allogeneic HLA class I-specific cytotoxic T cells. Keratinocyte ICAM-1 (CD54) and T cell LFA-1 (CD11a/CD18) mediate enhanced lysis of IFN-gamma-treated keratinocytes.

Exposure of human KC to IFN-gamma increases their susceptibility to lysis by CTL. The mechanism of this enhanced lysis was investigated by analyzing interactions of IFN-gamma-treated and nontreated cultured KC with allogeneic class I-specific CTL clones. rIFN-gamma treatment augmented KC lysis in a time- and dose-dependent manner. Increased lysis of IFN-KC was detected after only 2 h of IFN-gamma treatment and was maximal by 12 h. Enhanced lysis of IFN-KC was Ag-specific, inasmuch as nonantigenic IFN-KC were not lysed either directly or as bystanders during the lysis of antigenic KC. Parallel immunofluorescence and cytotoxicity assays of KC treated with IFN-gamma for various intervals revealed a direct correlation between the degree of increased KC lysis and levels of cell surface ICAM-1 (CD54), but not of specific alloantigen or beta 2-microglobulin. Lysis of nontreated KC was blocked by mAb against class I or CD3, but not by mAb against ICAM-1 or LFA-1. In contrast, lysis of IFN-KC was partially inhibited by anti-ICAM-1 or anti-LFA-1 mAb, but resisted inhibition by anti-class I mAb except in the presence of anti-ICAM-1. These results indicate that both ICAM-1/LFA-1 and Ag/CD3-TcR interactions are important for Ag-specific lysis of IFN-KC, whereas lysis of nontreated KC depends on Ag/CD3-TcR but not ICAM-1/LFA-1 interactions. Equivalent inhibition of IFN-KC lysis by mAb against ICAM-1 or LFA-1 suggests that ICAM-1 is the only LFA-1 ligand involved in enhanced IFN-KC lysis. Furthermore, enhanced CTL lysis of KC after short-term IFN-gamma treatment can be explained solely on the basis of ICAM-1 induction, because all of the increase in specific lysis associated with IFN-gamma treatment could be blocked by mAb that block ICAM-1/LFA-1 interactions.     

Socioeconomic transition and physical growth of Tupí-Mondê Amerindian children of the Aripuan? Park, Brazilian Amazon

Anthropometric assessment of nutritional status is reported for three Tupí-Mondê-speaking groups from Rond?nia and Mato Grosso, Brazil. This region of the Amazon basin is experiencing rapid development through government-oriented colonization. The Gavi?o, Suruí, and Zoró had their first contacts with Brazilian national society at different times, and the nature and degree of their participation in regional markets varies. Height, weight, sitting height, subischial leg length, upper arm circumference, triceps skin-fold thickness, and upper arm muscle and fat areas are reported for children 0-10.9 years of age. Like other Amazonian Amerindians, Tupí-Mondê children are short for their age but normal or above normal in weight for height with respect to the National Center for Health Statistics reference. Hence stunting levels are high (55.4%) and wasting levels are low (0.8%). There are also deficits in body composition parameters, especially in upper arm circumference and estimated muscle and fat areas. We interpret the results as evidence of suboptimal nutritional status, reflecting the interaction between poor diet and infectious and parasitic diseases. The Gavi?o, with the longest period of contact, present the lowest level of stunting. This finding is attributed to the use of cash income from rubber tapping and nut gathering to purchase of food items and health care. Differences in height between the three groups are mostly due to leg length, instead of sitting height, reinforcing the idea that environmental conditions can alter body proportions.     

Multinuclear nuclear magnetic resonance studies of Na cation-stabilized complex formed by d(G-G-T-T-T-T-C-G-G) in solution. Implications for G-tetrad structures.

There has been much recent interest in the self-association of short deoxyguanosine-rich motifs within single-stranded DNAs to generate monovalent cation modulated four-stranded helical segments called G-quadruplexes stabilized by hydrogen-bonded G-tetrad alignments. We have addressed structural aspects of this novel alignment and report on multinuclear 1H, 31P and 13C nuclear magnetic resonance studies on the d(G2T4CG2) deoxynonanucleotide with Na cation as counterion in aqueous solution at low temperature. This sequence forms stable structures even though it cannot align by Watson-Crick hydrogen bond formation (see the paper on d(G2T5G2) describing optical and calorimetric measurements by Jin, R., Breslauer, K. J., Jones, R. A. & Gaffney, B. L. (1990), Science, 250, 543-546). The four narrow exchangeable protons detected between 11.5 and 12.0 parts per million (p.p.m.), which are common to the d(G2T4CG2) deoxynonanucleotide and the d(G2TCG2) deoxyhexanucleotide sequences, are assigned to deoxyguanosine imino protons hydrogen-bonded to carbonyl acceptor groups. These narrow imino protons are not detected for d(IGN5IG) and d(I2N5G2), where two deoxyguanosine residues are replaced by two deoxyinosine residues in the deoxynonanucleotide sequences. This implies that the 2-amino protons of deoxyguanosine must also participate in hydrogen bond formation and stabilize the structured conformation of d(G2T4CG2) in Na cation-containing solution. We have completely assigned the base and sugar H1', H2',2', H3', and H4' protons of the d(G2T4CG2) oligomer following analysis of two-dimensional nuclear Overhauser enhancement spectroscopy and two-dimensional correlated spectroscopy data sets in 0.1 M-NaCl, 10 mM-sodium phosphate, 2H2O solution at 0 degree C. The relative magnitude of the nuclear Overhauser enhancements (NOEs) between the base H8 and its own sugar H1' protons of individual deoxyguanosine residues establishes that G1 and G8 adopt syn orientations while G2 and G9 adopt anti orientations about the glycosidic bond in the d(G1-G2-T3-T4-T5-T6-C7-G8-G9) sequence in both Na and K cation-containing aqueous solution. Consequently, any structure proposed for the tetramolecular complex of d(G2T4CG2) must exhibit alternating G(syn) and G(anti) glycosidic torsion angles within each strand. The directionality and magnitude of the observed NOEs are consistent with the G(syn)-G(anti) steps adopting right-handed helical conformations in solution. We also note that the H8 protons of G1 and G8 (7.35 to 7.45 p.p.m.) in a syn alignment are shifted significantly upfield from the H8 protons of G2 and G9 (8.0 to 8.3 p.p.m.) in an anti alignment.(ABSTRACT TRUNCATED AT 400 WORDS)