Acetylsalicylic acid after iliac-femoro-popliteal interventions?

To determine whether acetyl salicylic acid (ASA) in a daily dose of 1500 mg versus untreated controls is effective in patients with peripheral arterial disease a prospective randomized but not placebo-controlled one single centre trial was undertaken. Patients were assigned to one of two groups by means of multi-dimensional contingency tables whereas the risk factors age, sex, height, body weight, diabetic metabolic state, hypertension, history of myocardial infarction, smoking habits and preoperative clinical status according to the Fontaine classification where found in the state of balance. 298 patients with arterial occlusions in the iliaco-femoro-popliteal level were recruited during 1971-1974, the primary end points were probability of patency and probability of survival. In regard as well as to the probability of patency (p less than 0.56 Breslow, p less than 0.66 Mantel) as to the probability of survival (p less than 0.10 Breslow, p less than 0.70 Mantel) no statistical significant difference was detected. In conclusion ASA, in the doses administered here, was unable to improve patency or prolong patient survival, an outcome, which is at variance with results obtained by others.     

Histopathologic analysis of atypical lesions in image-guided core breast biopsies.

Appropriate follow-up of patients with needle core breast biopsies (NCBB) showing atypical hyperplasia remains unclear because previous studies show that subsequent open biopsies in variable proportions of these patients reveal ductal carcinoma in situ (DCIS) or even invasive carcinoma, indicating significant sampling artifact. NCBB with diagnoses of atypia were morphologically classified into groups as follows: I, ALH (n = 24); II, ADH with minimal cytologic atypism (n = 90); III, atypia, other (9 columnar, 2 apocrine, 11 atypical papillary); IV, severe ADH/borderline DCIS (n = 31). Mammographic and histologic features, including the number of foci of atypia in the NCBB and the calcification span, were then correlated with presence of DCIS or invasive tumor in subsequent open excisions. Open excisional biopsies showed more severe lesions in 12% of Group I-III cases (8% in Group I, 9% in Group II, and 27% in Group III), of which 15 were DCIS and one was an invasive tubular carcinoma (0.3 cm). Of the DCIS, 60% (n = 9) were < or =5 mm, and 13 of 15 (87%) were low grade. The NCBB cavity was immediately adjacent to the more severe lesions in 88% (n = 14) of cases, in keeping with sampling error. The subset showing severe ADH with borderline nuclear features in contrast was associated with a high likelihood (63%) of DCIS in follow-up excisions. NCBB with atypical papillary features also showed a high frequency of DCIS (4/11, 36%) in subsequent open excisions. Other factors associated with more severe lesions on open biopsy included the number of atypical foci in the NCBB (>4, P <.05) and the mammographic calcification span (>2.0 cm, P <.0001). Atypical lesions diagnosed in NCBB samples are radiographically and morphologically heterogeneous, accounting for the variable frequency of DCIS or invasive neoplasm identified in subsequent open excisions, which are usually focal, low grade, and a consequence of sampling artifact (i.e., adjacent to the NCBB cavity). DCIS is more likely if microcalcifications are mammographically extensive or if atypia is multifocal or is associated with borderline cytologic features.     

Conformational variability of a picornavirus capsid: pH-dependent structural changes of Mengo virus related to its host receptor attachment site and disassembly

The structure of Mengo virus had been determined from crystals grown in the presence of 100 mM phosphate buffer at pH 7.4. It is shown that Mengo virus is poorly infectious at the phosphate concentration similar to that in which it was crystallized. Maximal infectivity is achieved at 10 mM phosphate or less in physiological saline. The phosphate effect is ameliorated when the pH is lowered to 4.6. Although it has not been possible to study the crystal structure of the virus at low phosphate concentrations, it is shown that increasing the Cl- concentration at pH 6.2 or decreasing the pH to 4.6 causes substantial conformational changes confined to the "pit," a deep surface depression. These structural changes involve a movement of the "FMDV loop" (GH loop) in VP1, an ordering of the "VP3 loop" (GH loop in VP3) between 3176 and 3182, the displacement of a bound phosphate near the "FMDV loop" (GH loop in VP1), and movement of the carboxy terminus of VP2. The changes in conformation are correlated with the dissociation of the virion into pentamers at pH 6.2 and 150 mM Cl-. The localization of the conformational changes and the correlated role of the phosphate in controlling infectivity support the hypothesis that the "pit" is the receptor attachment site.     

Gesundheitsinformationsverhalten 65+: Erreichbarkeit älterer Zielgruppen

Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Der Anteil älterer Personen in der Bevölkerung wächst stetig. Gleichzeitig steigen im Alter die Risiken für...     

Aufbau von Interventionsdatenbanken für mehr Evidenzbasierung in Prävention und Gesundheitsförderung – methodische Überlegungen

Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Kommunale AkteurInnen erfahren bei der Entwicklung und Auswahl von Maßnahmen der Prävention und...     

Acid-induced structural changes in human rhinovirus 14: possible role in uncoating.

X-ray diffraction data were collected from human rhinovirus 14 crystals a few minutes after exposure to acid vapor and prior to excessive crystalline disorder. Conformational changes occurred (i) in the GH loop of viral protein (VP) 1, (ii) at the ion binding site on the outer surface of the pentamer center, and (iii) in VP3 and VP4 on the virion's interior in the vicinity of the fivefold axis. Amino acid substitutions in mutants resistant to low pH, or to drugs that inhibit uncoating, were concentrated in the vicinity of the GH loop. It is proposed that the acid-induced changes reflect processes that trigger uncoating.     

Structural investigations of a Podoviridae streptococcus phage C1, implications for the mechanism of viral entry

The Podoviridae phage C1 was one of the earliest isolated bacteriophages and the first virus documented to be active against streptococci. The icosahedral and asymmetric reconstructions of the virus were calculated using cryo-electron microscopy. The capsid protein has an HK97 fold arranged into a T = 4 icosahedral lattice. The C1 tail is terminated with a φ29-like knob, surrounded by a skirt of twelve long appendages with novel morphology. Several C1 structural proteins have been identified, including a candidate for an appendage. The crystal structure of the knob has an N-terminal domain with a fold observed previously in tube forming proteins of Siphoviridae and Myoviridae phages. The structure of C1 suggests the mechanisms by which the virus digests the cell wall and ejects its genome. Although there is little sequence similarity to other phages, conservation of the structural proteins demonstrates a common origin of the head and tail, but more recent evolution of the appendages.     

Cryo-electron microscopy study of bacteriophage T4 displaying anthrax toxin proteins

The bacteriophage T4 capsid contains two accessory surface proteins, the small outer capsid protein (Soc, 870 copies) and the highly antigenic outer capsid protein (Hoc, 155 copies). As these are dispensable for capsid formation, they can be used for displaying proteins and macromolecular complexes on the T4 capsid surface. Anthrax toxin components were attached to the T4 capsid as a fusion protein of the N-terminal domain of the anthrax lethal factor (LFn) with Soc. The LFn-Soc fusion protein was complexed in vitro with Hoc(-)Soc(-)T4 phage. Subsequently, cleaved anthrax protective antigen heptamers (PA63)(7) were attached to the exposed LFn domains. A cryo-electron microscopy study of the decorated T4 particles shows the complex of PA63 heptamers with LFn-Soc on the phage surface. Although the cryo-electron microscopy reconstruction is unable to differentiate on its own between different proposed models of the anthrax toxin, the density is consistent with a model that had predicted the orientation and position of three LFn molecules bound to one PA63 heptamer.