Fungal horizons: the Asilomar Fungal Genetics Conference 2007.

This meeting report covers advances presented at the 2007 Asilomar Fungal Genetics Conference that expand our understanding of fungal biology and the myriad ways in which studies of organisms in this ubiquitous and successful kingdom of life advance an understanding of conserved biological principles.     

Controlling cell cycle progress in the fission yeast Schizosaccharomyces pombe.

The suitability of fission yeast as a model for understanding the eukaryotic cell cycle has been validated in five years of exciting developments. We review recent advances in understanding the nature of the controls that regulate progression through the cell cycle and the coordination of DNA replication and mitosis.     

Sequence alignment of the G-protein coupled receptor superfamily.

The multitude of G-protein coupled receptor (GPR) superfamily cDNAs recently isolated has exceeded the number of receptor subtypes anticipated by pharmacological studies. Analysis of the sequence similarities and unique features of the members of this family is valuable for designing strategies to isolate related cDNAs, for developing hypotheses concerning substrate-ligand and receptor-effector interactions, and for understanding the evolution of these genes. We have compiled and aligned the 74 unique amino acid sequences published to date and review the present understanding of the structural motifs contributing to ligand binding and G-protein coupling.     

Movement,activity and action: the role of knowledge in the perception of motion.

This paper presents several approaches to the machine perception of motion and discusses the role and levels of knowledge in each. In particular, different techniques of motion understanding as focusing on one of movement, activity or action are described. Movements are the most atomic primitives, requiring no contextual or sequence knowledge to be recognized; movement is often addressed using either view-invariant or view-specific geometric techniques. Activity refers to sequences of movements or states, where the only real knowledge required is the statistics of the sequence; much of the recent work in gesture understanding falls within this category of motion perception. Finally, actions are larger-scale events, which typically include interaction with the environment and causal relationships; action understanding straddles the grey division between perception and cognition, computer vision and artificial intelligence. These levels are illustrated with examples drawn mostly from the group''s work in understanding motion in video imagery. It is argued that the utility of such a division is that it makes explicit the representational competencies and manipulations necessary for perception.     

Cultured smooth muscle approach in the study of hypertension.

The systemic vasculature is known to undergo marked change in both human and experimental hypertension. The in vitro study of individual cellular components from the blood vessel wall and the regulation of their intracellular biochemical processes will aid in developing an understanding of the pathogenesis of hypertension. Vascular smooth muscle cells derived from the aorta and mesenteric arteries of normotensive and hypertensive rats can be successfully maintained in culture, providing a system free of confounding variables such as blood pressure. To assist in fully understanding the pathophysiology of hypertension, this cell culture model can be used to examine interactions between receptor and ligand, the transduction of an associated signal, characterization of subsequent intracellular responses and ultimately, quantification of a physiological and functional consequence of these events, for example, proliferation. The application of in vitro techniques to hypertension research will continue to contribute new knowledge to increase our understanding of the mechanisms behind the hypertensive disease process.     

Keith R. Porter Lecture, 1996. Of mice and men: genetic disorders of the cytoskeleton.

Since the time when I was a postdoctoral fellow under the supervision of Dr. Howard Green, then at the Massachusetts Institute of Technology, I have been interested in understanding the molecular mechanisms underlying growth, differentiation, and development in the mammalian ectoderm. The ectoderm gives rise to epidermal keratinocytes and to neurons, which are the only two cell types of the body that devote most of their protein-synthesizing machinery to developing an elaborate cytoskeletal architecture composed of 10-nm intermediate filaments (IFs). Our interest is in understanding the architecture of the cytoskeleton in keratinocytes and in neurons, and in elucidating how perturbations in this architecture can lead to degenerative diseases of the skin and the nervous system. I will concentrate on the intermediate filament network of the skin and its associated genetic disorders, since this has been a long-standing interest of my laboratory at the University of Chicago.     

Beta-globin-gene haplotypes, mitochondrial DNA, the Y-chromosome: their impact on the genetic epidemiology of the major structural hemoglobinopathies.

The history of the discovery of the globin beta-like globin-gene haplotypes and their importance in the understanding of hemoglobinopathies has been reviewed recently. We will add in this review more recent findings and other molecular genetic tools that can help in the understanding of the genetic epidemiology of structural hemoglobinopathies, leaving the thalassemias for a later effort.     

Information processing in the auditory brainstem.

The past year has seen significant advances in our understanding of the structural (circuitry and chemistry of synaptic connections) and functional characteristics of the auditory brainstem. Some of the findings that shed light on the mechanisms underlying complex auditory information processing are highlighted.     

Fisher Lecture: the 2002 R. A. Fisher lecture: dedicated to the memory of Shanti S. Gupta. Variances are not always nuisance parameters

In classical problems, e.g., comparing two populations, fitting a regression surface, etc., variability is a nuisance parameter. The term "nuisance parameter" is meant here in both the technical and the practical sense. However, there are many instances where understanding the structure of variability is just as central as understanding the mean structure. The purpose of this article is to review a few of these problems. I focus in particular on two issues: (a) the determination of the validity of an assay; and (b) the issue of the power for detecting health effects from nutrient intakes when the latter are measured by food frequency questionnaires. I will also briefly mention the problems of variance structure in generalized linear mixed models, robust parameter design in quality technology, and the signal in microarrays. In these and other problems, treating variance structure as a nuisance instead of a central part of the modeling effort not only leads to inefficient estimation of means, but also to misleading conclusions.     

Exploring the nonlinear dynamics of the brain.

The growing need for a better understanding of large-scale brain dynamics has stimulated in the last decade the development of new and more advanced data analysis techniques. Progress in this domain has greatly benefited from developments in nonlinear time series analysis. This review gives a short overview of some of the nonlinear properties one may wish to infer from brain recordings and presents some examples and recent applications.     

Bionformation: untangling the networks of life.

The growth of numerous subdisciplines at the interface between biology and computer science paves the way for reconsidering the special relationship between information and life. In this sense, the term 'bioinformation' appears as an integrative notion that is useful to promote a new understanding of the heterogeneous networkings that characterize life. Two conceptual avenues are explored here: representation and symmetry. It is argued that the special organization of the living cell, based on the overlapping of both sequential and 'amorphous' architectures, endlessly strives to fill in the occurring 'functional voids' or symmetry breakings; and it endlessly produces physiological networkings and evolutionary novelties as a byproduct. Characterizing the special dynamics inherent in the living cell may be a precondition for understanding the information-production processes on which other emergent informational entities are based, particularly, nervous systems and societies.     

Biogenesis of the bacterial pilus.

The assembly of surface structures in gram-negative bacteria requires specialized secretion and chaperone systems localized on both sides of the cytoplasmic membrane. Major advances have been made over the last year in understanding how these systems form part of a general strategy used by bacteria to cap and target interactive subunits imported into the periplasmic space to outer membrane uncapping and assembly sites.     

Objectives and Program of the A.M.A. Committee on Nursing

The continued achievement of high standards of patient care in the preventive, curative, and restorative aspects of illness depends upon a harmonious, collaborative relationship between medicine and nursing. In an effort to protect and foster an enduring alliance of understanding and cooperation between these 2 major health professions, the Committee on Nursing has instituted a continuing program of liaison, communication, education, and research. The Committee has authorized publication of the following report on its objectives and program.     

Attraction vs. repulsion: the growth cone decides.

Axons are guided through their environment in response to signals provided by extracellular cues. These cues are transduced into motile responses by the tip of the growing axon, the growth cone, and can be either repulsive or attractive in nature. Recent studies have suggested that how an axon responds to any given signal depends on the internal state of the growth cone. This review discusses these studies and their importance for understanding how nerve connections are made in the developing embryo.     

Between biology and chemistry in the Enlightenment: how nutrition shapes vital organization. Buffon,Bonnet, C.F. Wolff

History and Philosophy of the Life Sciences - In teasing out the diverse origins of our “modern, ecological understanding of epidemic disease” (Mendelsohn, in: Lawrence and Weisz (eds)...     

Experiences in Teaching Scientific Writing in the U.S.A.

The origin and intended meaning of the phrase ‘survival of the fittest’ are discussed. The development of the concept of ‘fitness’ in a neo-Darwinian sense is traced, and the use of the term in other contexts is outlined. The treatment of ‘fitness’ in various popular biology texts is considered, and some suggestions about the use of the term in schools are made.

The relationship of interpretations of ‘fitness’ to a broader understanding of evolutionary mechanisms is stressed throughout.     

APC: the plot thickens.

Adenomatous polyposis coli (APC) is an important tumour suppressor in the human colon. It is conserved between human and flies, and promotes, together with Axin and glycogen synthase kinase 3 (GSK3), the degradation of the Wnt-signalling effector beta-catenin. Recent experiments have shaped our understanding of how Axin and GSK3 function but the role of APC in this process remains elusive.     

Neuronal interactions with the extracellular matrix.

The interactions of neurons with extracellular cues are important in directing the formation of precise neuronal networks during the development of the nervous system. This review will focus on recent progress towards the understanding of the molecular machinery involved in the interactions of neurons with the extracellular matrix.