Influence of risk factors and pharmacological treatment on mortality in patients with essential hypertension

BACKGROUND: The V JNC consensus stated that although new antihypertensive agents, such as angiotensin converting enzyme inhibitors and calcium channel blockers, are considered safer drugs, there is no firm evidence from large controlled trials that these drugs are associated with a lower cardiovascular mortality. AIM: To study the association between cardiovascular risk factors, blood pressure levels, pharmacological treatment and mortality in a group of hypertensive patients followed at an hypertension outpatient clinic. PATIENTS AND METHODS: Patients with essential hypertension were treated with different antihypertensive medications, according to physicians criteria, and controlled until death or loss from follow up. Causes of death were obtained from hospital records and death certificates. Survival was analyzed using life tables, comparisons between groups of patients were done using chi square or a Cox's proportional hazards model. RESULTS: Three hundred thirty-nine hypertensive patients aged 33 to 80 years old were followed for a mean period of 9.8 +/- 4.9 years. Eighty-six were treated with beta blockers, 64 with diuretics, 133 with calcium antagonists and 56 with ACE inhibitors. Blood pressure dropped similarly with all medications. During follow up, 79 patients died. Life table analysis showed that patients with a history of angina, diabetes or myocardial infarction had higher mortality rates. Similarly, patients treated with beta blockers and diuretics had higher mortality than patients treated with calcium antagonists or angiotensin converting enzyme inhibitors. The proportional hazards model showed that the effect of treatment modality persisted after correction for the other risk factors for mortality. CONCLUSIONS: In this series of hypertensive patients, those treated with beta blockers or diuretics had higher mortality rates than those receiving calcium channel antagonists or angiotensin converting enzyme inhibitors.     

Attachment theory and group processes: The association between attachment style and group-related representations, goals, memories, and functioning.

Four studies examined attachment-style differences in group-related cognitions and behaviors. In Studies 1-2, participants completed scales on group-related cognitions and emotions. In Studies 3-4, participants were divided into small groups, and their performance in group tasks as well as the cohesion of their group were assessed. Both attachment anxiety and avoidance in close relationships were associated with negative group-related cognitions and emotions. Anxiety was also related to the pursuit of closeness goals and impaired instrumental performance in group tasks. Avoidance was related to the pursuit of distance goals and deficits in socioemotional and instrumental performance. Group cohesion significantly moderated the effects of attachment anxiety. The discussion emphasizes the relevance of attachment theory within group contexts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mechanical properties of a modified acrylic bone cement with etoxytriethyleneglycol monomethacrylate

With the aim of improving some of the disadvantages of the acrylic bone cements, an acrylic bone cement based on polymethyl methacrylate has been modified by substituting different quantities, up to 20%, of the monomer methyl methacrylate (MMA) with the same amount of ethoxytriethyleneglycol monomethacrylate (TEG). The addition of this new monomer decreased noticeably the maximum temperature and increased both setting and working times. Mechanical testing revealed that the introduction of TEG gave rise to a less fragile bone cement by increasing slightly the total deformation without any change in the rest of the tensile parameters.     

A method to evaluate the tensile strength and stress-strain relationship of carbon nanofibers, carbon nanotubes, and C-chains

A method is introduced to assess the tensile strength of carbon nanofibers, carbon nanotubes (CNTs), and linear chains of carbon atoms (C-chains) obtained from thin amorphous carbon films by electron irradiation. Transmission electron microscopy images show that the nanofibers undergo a radiation-induced necking process, characterized by CNT formation and often followed by the formation of a C-chain. Simulations of the necking process are carried out to determine the tensile stress supported by the nanofiber and CNT neck.     

Specific digestive deficiency of phagocytes in paracoccidioidomycosis. Its absence in peripheral blood neutrophils of members of the nuclear family of patients. An initial report

Paracoccidioidomycosis (PARA) affects only a minority of individuals, who have presumably been exposed to the causative fungus (Paracoccidioides brasiliensis). Neutrophils (PMNs) from patients with PARA show a significant and specific digestive deficiency phagocytosed P. brasiliensis in vitro. It is not known whether the defect is acquired after contact with the fungus, or precedes it. We studied the spouses and offspring of three patients with PARA. Individuals studied stayed in the same house as their husband or father. None of the relatives had evidence of PARA, and their PMNs showed no defect in their ability to digest or kill the fungus. Relatives showed no indication of sensitization against P. brasiliensis. These results are compatible with the view that effective contact with P. brasiliensis may occur only under restricted conditions and that the defect in digestive ability is an infrequent and specific occurrence.     

Multicasting to multiple groups over broadcast channels

Multicasting is a communication mode in which a given source communicates with a subset of the entire network user population. Previous work in this area concentrated on the multicast problem of a single source that always communicates with the same destination group. In this paper we investigate a more natural case of multicast communication where a single source communicates with several different destination groups. Specially, we focus on the design and analysis of multicast data link protocols for this environment. Straightforward implementations of such protocols are inappropriate in the case of a large destination population, as a source will have to store a large amount of state information even if it maintains only a single variable per destination. In most typical applications, though. The total destination population is large, the number of destinations that any given source is in conversation with, is typically small. We propose a framework for adapting protocols so that memory requirement does not grow with the total destination population but depends upon the number of destinations actually in communication with the source. The savings in memory are achieved by slightly increasing the amount of communication. We address the performance of such a protocol in an environment of a broadcast channel. We analyze several strategies and control techniques and demonstrate the tradeoff between throughput and the amount of memory     

Structural and electron paramagnetic resonance (EPR) studies of mononuclear molybdenum enzymes from sulfate-reducing bacteria

Molybdenum and tungsten are found in biological systems in a mononuclear form in the active site of a diverse group of enzymes that generally catalyze oxygen-atom-transfer reactions. The metal atom (Mo or W) is coordinated to one or two pyranopterin molecules and to a variable number of ligands such as oxygen (oxo, hydroxo, water, serine, aspartic acid), sulfur (cysteines), and selenium (selenocysteines) atoms. In addition, these proteins contain redox cofactors such as iron-sulfur clusters and heme groups. All of these metal cofactors are along an electron-transfer pathway that mediates the electron exchange between substrate and an external electron acceptor (for oxidative reactions) or donor (for reductive reactions). We describe in this Account a combination of structural and electronic paramagnetic resonance studies that were used to reveal distinct aspects of these enzymes.     

Temperature stimuli-responsive nanoparticles from chitosan-graft-poly(N-vinylcaprolactam) as a drug delivery system

This work describes the preparation of thermosensitive chitosan-graft-poly(N-vinylcaprolactam) nanoparticles by ionic gelation and their potential use as a controlled drug delivery system, using doxorubicin as a model drug. A systematic study of the effect of the main processing parameters on both the size and thermoresponsive behavior of nanoparticles was investigated. The size of the particles is strongly dependent on the length of the poly(N-vinylcaprolactam) grafted chains and the concentration of the copolymer and crosslinking agent solutions. The molecular structure of the copolymer plays an essential role in the phase transition temperature of the particles, which decreases with the length of PVCL grafted chain. The system displayed proper drug-association parameters, and the drug-loaded nanoparticles exhibited dose-dependent cytotoxicity. A significant increase in the doxorubicin delivery rate was observed above the phase transition temperature (40 °C). These features indicate that these nanoparticles are suitable for the development of a new thermally controlled anti-cancer drug delivery system. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47831.