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To determine the difference, if any, between the reduction of bacteria on contaminated normal skin and contaminated superficially abraded skin following standard surgical preparations at clinically relevant time points after injury.Prospective animal study.Laboratory.Thirty-two New Zealand white rabbits.Two sites, two by two centimeters, one abraded and one nonabraded (control), were studied on each rabbit. Both were inoculated with encapsulated Staphylococcus aureus strain Wood 46. Four six-millimeter punch biopsies were obtained after inoculation, immediately before surgical scrub, and five minutes and then two hours after completion of the surgical scrub. The rabbits were divided into four cohort groups with surgical scrubs performed at six, twelve, twenty-four, and forty-eight hours after inoculation. Bacterial counts were determined.Numbers of bacteria on surgical sites.Before surgical preparation, the amount of bacteria on the normal skin (control sites) dropped significantly (p0.02) except in the six-hour group (p0.20). At the abraded skin sites, the bacteria flourished. The surgical scrub dropped bacterial counts at both the abraded and nonabraded skin sites significantly (p0.05) except for the abraded site in the twenty-four-hour group (p0.08). However in the twelve-, twenty-four-, and forty-eight-hour groups, the bacterial counts (colony-forming units) were still markedly elevated (1x10(5) at abraded sites) when compared with the nonabraded skin sites (p0.008) at the respective time intervals. Only at the six-hour interval were the bacterial counts reduced similarly at both the abraded and nonabraded skin sites.In a rabbit model the standard surgical preparation using povidone-iodine at six hours after inoculation is effective in reducing the bacterial count on abraded skin to that of surgically prepared nonabraded skin. Beyond that time, the standard surgical preparation is ineffective in reducing counts to those of nonabraded skin at similar time intervals.

Staphylococcus aureus is the principal causative agent of the inflammatory bone disease osteomyelitis. Unfortunately, the pathogenesis of this often chronic infection is poorly understood and is complicated by the recent observation that bone-forming osteoblasts can harbor S. aureus. Such an infection presents a significant challenge for the host immune response, because osteoblasts are not known to initiate protective cell-mediated immune responses. Cultured mouse and human osteoblasts infected with S. aureus were found to express high levels of interleukin (IL)-6 and IL-12p75, on the basis of complementary investigations demonstrating both S. aureus-induced up-regulation of expression of IL-6 and IL-12p40 mRNA and secretion of IL-6 and IL-12p75 by these cells. Additionally, a quantitative bioassay demonstrated that IL-12p75 secreted after infection was biologically active. These studies are the first to demonstrate induced IL-12p75 expression by osteoblasts and suggest a previously unrecognized role for osteoblasts in initiating immune responses after S. aureus infection.

Staphylococcus aureus is a bacterial pathogen causing approximately 80% of all cases of human osteomyelitis. This bacterium can adhere to and become internalized by osteoblasts and previous studies indicate that osteoblasts are active in the internalization process. In the current study, we examined the roles of microfilaments, microtubules and clathrin-dependent receptor-mediated endocytosis in the internalization of S. aureus by MC3T3-E1 mouse osteoblast cells. Microfilament and microtubule polymerization was inhibited with cytochalasin D and colchicine. Clathrin-coated pit formation was examined by using the transaminase inhibitor, monodanslycadaverine. The results of this study indicate that mouse osteoblasts utilize actin microfilaments, microtubules and clathrin-coated pits in the internalization of S. aureus; however, microfilaments seem to play the most significant role in the invasion process.

Staphylococcus aureus is a frequent cause of orthopedic infections in humans. The bacterium expresses several adhesins that facilitate bacterial binding to the bone matrix and to bone implant biomaterials coated with host plasma constituents. The relevant S. aureus adhesins are termed microbial surface components recognizing adhesive matrix molecules (MSCRAMMs) and specific MSCRAMMs are involved in bone and joint infections.

Intracellular polysaccharides (IPS) are glycogen-like storage polymers which contribute significantly to Streptococcus mutans -induced cariogenesis. We previously identified and cloned a locus from the S. mutans chromosome which is required for the accumulation of IPS. Sequencing of this locus revealed at least four contiguous open reading frames, all of which are preceded by a common promoter region and are transcribed in the same direction. Analysis of the amino acid sequence deduced from the first of these open reading frames (ORF1) revealed domains which are highly conserved among d -alanine-activating enzymes (DltA) in Lactobacillus rhamnosus (formerly Lactobacillus casei ) and Bacillus subtilis . The deduced amino acid sequences derived from ORF2, -3, and -4 also exhibit extensive similarity to DltB, -C, and -D, respectively, in these microorganisms. However, Southern hybridization experiments indicate that this operon maps to a locus on the S. mutans chromosome which is separate from the glgP , glgA , and glgD genes, whose products are known mediators of bacterial IPS accumulation. We therefore assigned a new dlt designation to the locus which we had formerly called glg . We maintain that the dlt genes are involved in S. mutans IPS accumulation, however, since they complement a mutation in trans which otherwise renders S. mutans IPS deficient. In this study, we found that expression of the S. mutans dlt genes is growth phase dependent and is modulated by carbohydrates internalized via the phosphoenolpyruvate phosphotransferase system (PTS). We demonstrated that the S. mutans dlt genes are expressed constitutively when non-PTS sugars are provided as the sole source of carbohydrate. Consistent with a role for the PTS in dlt expression is a similar constitutive expression of the dlt genes in an S. mutans PTS mutant grown in a chemically defined medium supplemented with glucose. In summary, these findings support a novel role for the dlt gene products in S. mutans IPS accumulation and suggest that dlt expression in this oral pathogen is subject to complex mechanisms of control imposed by growth phase, dietary carbohydrate, and other factors present in the plaque environment.

Laboratory studies of bacterial gene expression have not allowed the investigation of in vivo factors crucial to pathogenesis. Recently, genetic tools have been used to identify in vivo-activated genes. These tools, however, have not allowed the measurement of specific expression levels of virulence-associated bacterial genes in vivo. This report describes a system, previously tested utilizing the fructosyltransferase (ftf) gene of Streptococcus mutans, that allows the measurement of activity of specific virulence-associated streptococcal genes while bacteria are living in the animal environment.

The goal of this investigation is to develop poly(DL-lactide-co-glycolide) (PLGA) nanoparticles for the delivery of antibiotics such as nafcillin to osteoblasts. This is important in order to treat Staphylococcus aureus-mediated osteomyelitis. The latter is often chronic and highly resistant to antibiotics. Nafcillin (a penicillinase-resistant penicillin)-loaded nanoparticles were prepared by a single emulsion/solvent evaporation method. In vitro drug release studies were conducted in an incubator shaker at 37 degrees C in phosphate buffer saline. Drug loading and release were determined by UV-Vis spectroscopy. A viability study was conducted in S. aureus-infected mouse osteoblasts. In vitro release study showed an initial burst release and a second phase of slow release. Following 24 and 48 h of incubation, all formulations of nanoparticles loaded with nafcillin either killed or significantly reduced all of the intracellular bacteria. Our data demonstrate that effective killing of intracellular S. aureus is possible by treating the infected osteoblasts with nanoparticles loaded with nafcillin.

Background Staphylococcus aureus infection of normal osteoblasts induces expression of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL).

Part 1 The changing Arab regional system: the Arab world and the new balance of power in the new Middle East, Bahgat Korany the prospects for Arab co-operation in a changing regional and global system, Paul Noble from Pan-Arabism to the community of sovereign Arab states -redefining the Arab and Arabism in the aftermath of the Second Gulf War, Bassam Tibi. Part 2 Experiments in political integration: the rise and fall of the United Arab Republic, Mustapha Kamil Al-Sayyid the United Arab Emirates - a quarter century of federation, Frauke Heard-Bey The Gulf Cooperation Council - nature, origin, and process, Abdul Khaleq Abdulla the ups and downs of Maghrib unity, I. William Zartman The Republic of Yemen - the politics of unification and civil war, 1989-1995, Robert D. Burrowes.

The risk of bacteremia secondary to high pressure lavage of contaminated wounds was assessed. Twenty canines were divided randomly into four treatment groups. A 10-cm incision was made over the left shoulder of each dog. The deltoideus muscle was disrupted and traumatized. Groups A and B (n = 8) had wound contamination with 1.4 x 10(9) Staphylococcus aureus followed 75 minutes later by high pressure lavage or bulb syringe irrigation, respectively. Groups C and D (n = 2) had no contamination, followed by the same treatment. Bacterial counts were obtained before and after wound irrigation. Blood cultures were obtained before, during, and 15 minutes after irrigation. Positive control cultures were obtained during injection of bacteria into the antecubital vein. A detectable bacteremia did not occur during or after high pressure lavage or bulb syringe irrigation of acute contaminated wounds but did occur in 18 of 20 positive controls. Bacterial levels were reduced by an average of 70% +/- 10% by high pressure lavage and 44% +/- 50% by bulb irrigation. Reduction of wound bacteria was achieved more consistently with high pressure lavage than with bulb syringe irrigation.

Most Americans have not experienced life under enemy military occupation, yet one frequently reads in the American press that the Israeli occupation is relatively liberal and benign, as occupations go. After a month of conversations with Palestinians under Israeli occupation I am inclined to doubt the validity of such assertions. The objective evidence of Israeli intentions in the territories, which can only be described as "creeping" (if not galloping) annexation, is now ubiquitous: the building of settlements, the continuing seizure of land and the manipulation of water resources. The subjective factors, which account for the grim outlook of the Palestinians, are manifested by the sense of powerlessness and degradation that accompanies the checkpoints, the armed patrols, the military bureaucracy and the punishment for alleged resistance or political activity.

When I told some of my colleagues and students that I wanted to address the question of democratization in Middle East politics at the annual meeting, I was not surprised at their reactions, which were mainly incredulous. If ever a topic were passé, surely it was this one. Not only was the experience of parliamentary democracy brief and unhappy, it also had ended by the middle 1950s. Furthermore, the liberal modernization paradigm that had underpinned earlier forecasts of democracy was itself largely discarded. In addition, my friends argued, how could I try to make a case for democratization when my own writing on Arab politics portrayed fragmented, disoriented societies and unstructured, insecure political environments in which the race between societal demands and state capabilities—no matter which side was “ahead”—could hardly be conducive to democracy. Skeptical colleagues from Egypt and other Arab countries also raised the troublesome question of academic and ideological ethnocentrism: should one even ask about prospects for democratization?

(1976). The Lebanese Crisis: The Limits of Consociational Democracy. Journal of Palestine Studies: Vol. 5, No. 3-4, pp. 109-122.

This paper attempts to describe the re-emergence of a Palestinian Arab national movement, the Palestinian resistance (al-Muqawama al-Filastiniya) during the years following the Arab-Israeli war of June 1967. Perspectives and concepts from comparative politics are employed to facilitate description and evaluation. An effort is made to assess the violence capabilities, structural development, and ideological trends of the movement in light of general theoretical considerations and also in the context of the politics of the Arab world. From the spring of 1968 until the fall of 1970, the guerrillas developed the capacity to carry out serious protracted violence against Israel. The guerrilla organizations themselves became more elaborate structurally and began to develop important political functions of a nation-building character. The movement was becoming more radical ideologically, a development which reinforced its overall cohesion although serious elite rivalries persisted. These developments increased the influence of the movement over Arab governments, but they also increased its threat potential, thus complicating the relationship. As far as the superpowers were concerned, the Palestinians injected an element of instability into the local political-military situation and a consequent additional risk of great-power confrontation. Thus, when Jordan and the United States moved to eliminate guerrilla activities from Jordan the Palestinians found they had no effective outside supporters.

L'auteur analyse l'influence des divers groupes de pression qui, à propos du conflit israélo-arabe, agissent sur le Congrès et l'opinion publique. Il rappelle leurs organisations et leurs moyens. Ces données internes permettent de mieux apprécier dans quelles conditions et à l'intérieur de quelles limites l'Exécutif peut appliquer la diplomatie américaine., Hudson Michael C. Politique intérieure et politique extérieure américaine dans ses rapports avec le conflit israélo-arabe. In: Politique étrangère, n°6 - 1974 - 39ᵉannée. pp. 641-658.

T HE ABUNDANCE OF BOTH DATA and theory in political development today makes it a fascinating field, but the gap between them continues to frustrate its students.1 What follows is an attempt to explore this gap by trying to harness both data and theory to the study of development in the single state. The case selected for examination is Lebanon, but this is unimportant for the main interest here is methodological. The basic object is to employ comparative quantitative data to illuminate the relation between social mobilization and political development.

Promoter-cloning plasmids were constructed and have been used to isolate transcriptionally active DNA fragments from Staphylococcus aureus. The plasmids contain a chloramphenicol acetyltransferase (CAT) gene of Gram-positive (G+) origin which lacks both its promoter and the sequence responsible for CAT inducibility. The ability of S. aureus promoters to direct CAT expression in Escherichia coli and Bacillus subtilis was examined. Two classes of staphylococcal promoter sequences have been obtained. Class I DNA fragments direct CAT expression in S. aureus, B. subtilis, and E. coli, while class II DNA sequences direct CAT expression only in the G+ hosts.

The document contains a listing of nations of the world with their assigned Archive code numbers, followed by data on several variables studied. These include population, agricultural area, vital statistics, life expectancy, telephones, lettermail, mass media, literacy, educational enrollments, steel and energy consumption, land data, occupations, political activity, assistance, gross national product, and other facets of national economy.

Scholars and policy-makers frequently assume that the new states must develop stability before they can hope to operate the complex and delicate institutions of liberal democracy. But in the case of the Lebanese Republic this relationship is reversed: democratic institutions have brought about and maintained stability in an unfavorable political environment. The Lebanese case suggests that formal institutions, although neglected in behavioral political science, deserve renewed attention as causal agents in the process of political modernization.1 At the same time, it raises the question of whether such institutions can supply enough systematic flexibility to meet the social mobilization demands of a rapidly changing society. Lebanon's fragmented body politic-its traditional pluralism-has necessitated a political system based upon the balance of power, in the absence of positive legitimacy for the institutions of the state. In turn, the balance of power has required institutions that promote democratic values. Without the democratic institutions the balance of power would cease to be stable, and without stability the state would cease to exist. Lebanon's representative institutions are an essential condition of its stability, not a lucky byproduct. This relationship, of course, has not gone unnoticed by Lebanon's politicians. In his inaugural address of September 23, 1964, President Charles Helou said: "I believe that the democratic system is an intrinsic necessity for our country.... It assures a balance between powers and makes possible a fruitful meeting among the Lebanese spiritual families. Thus their energies are activated within the democratic foundations, and their needs are met within a framework of brotherly cooperation. Rule is consultative, and the consultative system in Lebanon is one of the conditions of cooperative and stable life."2 This situation, however, is no cause for unrestrained optimism on the part of advocates of moderate democracy. First, the Lebanese system is democratic only in a limited sense. Second, modernization creates a dilemma for this balance-of-power system because it burdens a weak governmental