Permease on parade: application of site-directed mutagenesis to ion-gradient driven active transport

Oligonucleotide-directed, site-specific mutagenesis is being applied to the problem of ion-gradient driven active transport with the lac permease as a model system. It has been shown that Arg-302, His-322 and Glu-325, neighboring residues in putative transmembrane helices IX and X, play an important role in lactose-coupled H⁺ translocation, possibly as components of a catalytic triad similar to that found in the serine proteases. In addition, Cys residues, long thought to be involved in the mechanism of the permease, are not directly involved in either substrate binding or H⁺ translocation. Finally, a variety of mutations have no effect on permease activity indicating that single amino acid changes do not lead indiscriminately to long-range conformational alterations.     

The genomics parade of defense responses: to infinity and beyond

Genomic-scale methods, such as cDNA microarrays, cDNA-AFLP analyses and proteomics are revolutionizing the study of plant-pathogen interactions, and are revealing a complex web of signaling cascades involved in plant defense responses. Recent studies have shown that responses to pathogens and environmental stresses are linked, suggesting that genes previously identified as stress-responsive may also play an active role in plant defense. As a result of proteomic analysis, proteins involved in early defense signaling are coming to light.     

Female mate choice through spawning parade formed by male-male competition in filefishRudarius ercodes

In the small filefishRudarius ercodes inhabiting temperatre seaweed beds, 2–10 males follow a gravid female, in a line until spawning early in the morning. Formation of the spawning parade and change of male order were investigated in a large aquarium. Males competed for the position nearest to the female during the parade, while the female controlled the parade by her swimming speed and course. During the parade, male members and their order changed frequently. The male order in the parade was related with the intensity of nuptial coloration, which changed according to the social rank. The female sometimes tried to take a spawning posture but rejected spawning when male positioning was not good for her, for example, far different from parading order. The female spawned with 2–5 males on each side. The nearest mating positions to the female were usually occupied by two males that had been staying at an anterior position in the parade for a long time. During the spawning parade over a long distance and time, females ofR. ercodes can choose multiple suitable males in a variable environment like a temperate seaweed bed.     

Metalloproteinases: A parade of functions in matrix biology and an outlook for the future

This issue of Matrix Biology is devoted to exploring how metalloproteinases – here inclusive of related families of extracellular proteinases – act on extracellular matrix (ECM) proteins to influence an astonishing diversity of biological systems and diseases. Since their discovery in the 1960's, matrix metalloproteinases (MMPs) have oft and widely been considered as the principal mediators of ECM destruction. However, as becomes clear from several articles in this issue, MMPs affect processes that both promote and limit ECM assembly, structure, and quantity. Furthermore, it has become increasingly apparent that ECM proteolysis is neither the exclusive function of MMPs nor their only sphere of influence. Thus, other enzymes may be important participants in ECM proteolysis, and indeed they are. The ADAMTS (a disintegrin-like and metalloproteinase domain with thrombospondin type 1 repeat) proteinases, BMP/tolloid proteases, and meprins have all emerged as major mechanisms of ECM proteolysis. An aggregate view of proteolysis as an exquisitely specific and crucial post-translational modification of secreted proteins emerges from these reviews. The cumulative evidence strongly suggests that although some MMPs can and do cleave ECM components, notably fibrillar collagens, the majority of these proteinases are not key physiological participants in morphogenesis nor in control of matrix metabolism in homeostasis or disease. In contrast, deficiency of ADAMTS proteases leads to a remarkable array of morphogenetic defects and connective tissue disorders consistent with a specialized role in turnover of the embryonic provisional ECM and in ECM assembly. Astacin-related proteases emerge into crucial positions in ECM assembly and turnover, although they also have numerous roles related to morphogen and growth factor regulation. To further turn the traditional view on its head, it is clear that many MMPs are key participants in many, diverse immune and inflammation processes rather than ECM proteolysis. The overlap in the activities within and between these families leads to the view that ECM proteolysis, which is indispensable for life, was over-engineered to an extraordinary extent during vertebrate evolution. That these proteinases, which likely evolved within networks regulating morphogenesis, immunity and regeneration, also participate in diseases is a side effect of human longevity. Attempts to inhibit metalloproteinases in human diseases thus require continuing appraisal of their biological roles and cautious evaluation of potential new therapeutic opportunities.     

The Privatisation of Home and Hope: Return, Reforms and the Foreign Intervention in Bosnia-Herzegovina

Contextualising the foreign-imposed return policies in early post-war Bosnia-Herzegovina, this article argues that the return of the displaced – however important it was to many Bosnians – ultimately functioned as the self-perpetuating lynchpin of an externally generated framework for post-war reconstruction, often out of tune with the hopes of its intended beneficiaries. Rather than following conventional anthropological cultural relativist arguments, I propose a critique of the foreign intervention that places it in its social, political and economic context, drawing attention to patterns of longing and belonging in Bosnia-Herzegovina. I contrast the groundings and implications of intervention policies with the experiences and yearnings of displaced Bosnians and show that, while it was legitimised as the implementation of an ostensibly ideologically neutral human rights discourse, the foreign emphasis on property and safety rights over other concerns channelled the reconstruction of Bosnia-Herzegovina into a peculiar, normative trajectory of postsocialist neoliberalisation.     

"Sweeping up after the parade": professional, ethical, and patient care implications of "turfing"

"Turfing" denotes a patient transfer or triage from one physician to another when the care of that patient feels more troublesome than it is worth. A widespread phenomenon in medical training programs, turfing appears to allocate patient care to meet physicians' rather than patients' needs. Although turfing reportedly causes inter-physician discord and inter-specialty stereotyping, its deeper consequences are poorly understood. Turfing is an interpersonal conflict masquerading as a medical issue. After examining turfing alongside other patient-related slang, I analyze the distinction between "the turf," a person, and "to turf," a practice. Several explanatory models from medical practice are explored in order to illuminate turfing's implications for medical professionalism, ethics, and patient care. I suggest that a physician's medical specialty or practice type--that is, professional culture--may link to that physician's degree of altruism. If so, then what it means fundamentally to be a physician might vary across medical specialties. Such a link calls for a new notion of cultural competence, one that physicians may apply not to patients but to each other.     

Public Reform and the Privatisation of Poverty: Some Institutional Determinants of Health Seeking Behaviour in Southern Tanzania

This paper explores the changing institutional context of health servicedelivery in rural Tanzania through an anthropological analysis of thekinds of healing strategies pursued by men and women when they are ill.In some rural districts popular dissatisfaction with state medicalprovision is not manifested in a rejection of the allopathic medicinewith which it is associated, but in increased reliance on an emerginginformal sector of private medical provision. Although this sectorprovides a valued and accessible service to certain categories ofclients it delivers poor quality treatment, serving to reinforce thecyclical relationship between poverty and ill health. Despite the bestintentions of major public sector reforms neither government nor otheragencies are able to meet rural demand for health services. Reliance onthe parallel market for medical provision is likely to continue, atleast in the short term, with negative consequences for health.     

Comments on L.S. Vygotsky's Theater Review on E.V. Gel'tser's Performance

This article presents detailed comments on L.S. Vygotsky's review of the famous Russian ballerina E.V. Gel'tser's performance during her Gomel tour in the autumn of 1922. We present a reconstruction of the cultural context, which is quite essential for understanding multiple aspects of the content of Vygotsky's review. We stress the importance of the distinction between artificial and natural movements introduced by Vygotsky's when considering the uniqueness of expressive movement in choreography.

The uniqueness of cathartic experience, which became a central theme in Vygotsky's research monograph The Psychology of Art (1925), is examined in this review using the analysis of classical dance perception. We establish the methodological importance of Vygotsky's account of the opposition between classical and so-called untaught, natural dance (I. Duncan and M. Fokine), which in turn makes it possible to designate the fundamental difference between “spiritual” [dukhovnyi] and “mental/emotional” [dushevnyi] experience.