48 research outputs found
The continuum limit of the static-light meson spectrum
We investigate the continuum limit of the low lying static-light meson
spectrum using Wilson twisted mass lattice QCD with N_f = 2 dynamical quark
flavours. We consider three values of the lattice spacing a ~ 0.051 fm, 0.064
fm, 0.080 fm and various values of the pion mass in the range 280 MeV < m_PS <
640 MeV. We present results in the continuum limit for light cloud angular
momentum j = 1/2, 3/2, 5/2 and for parity P = +, -. We extrapolate our results
to physical quark masses, make predictions regarding the spectrum of B and B_s
mesons and compare with available experimental results.Comment: 18 pages, 3 figure
Increased CSF levels of aromatic amino acids in hip fracture patients with delirium suggests higher monoaminergic activity
textabstractBackground: To examine whether delirium in hip fracture patients was associated with changes in the levels of amino acids and/or monoamine metabolites in cerebrospinal fluid (CSF) and serum. Methods: In this prospective cohort study, 77 patients admitted with an acute hip fracture to Oslo University Hospital, Norway, were studied. The concentrations of amino acids in CSF and serum were determined by high performance liquid chromatography. The patients were assessed daily for delirium by the Confusion Assessment Method (pre-operatively and post-operative day 1-5 (all) or until discharge (delirious patients)). Pre-fracture dementia status was decided by an expert panel. Serum was collected pre-operatively and CSF immediately before spinal anesthesia. Results: Fifty-three (71 %) hip fracture patients developed delirium. In hip fracture patients without dementia (n = 39), those with delirium had significantly higher CSF levels of tryptophan (40 % higher), tyrosine (60 % higher), phenylalanine (59 % higher) and the monoamine metabolite 5-hydroxyindoleacetate (23 % higher) compared to those without delirium. The same amino acids were also higher in CSF in delirious patients with dementia (n = 38). The correlations between serum and CSF amino acid levels were poor. Conclusion: Higher CSF levels of monoamine precursors in hip fracture patients with delirium suggest a higher monoaminergic activity in the central nervous system during delirium in this patient group
Night nursing â staff's working experiences
<p>Abstract</p> <p>Background</p> <p>Although the duties and working conditions of registered, and enrolled nurses have previously been described from different perspectives, they have not been examined from the night nursing aspect. The aim of the study was to describe the night nursing staff's working experiences.</p> <p>Methods</p> <p>The design of the study is qualitative and descriptive. Interviews were conducted with 10 registered and 10 enrolled nurses working as night staff at a Swedish University Hospital. The interview guide was thematic and concerned the content of their tasks, as well as the working conditions that constitute night nursing. In addition, the interviews were transcribed verbatim and analyzed using content analysis.</p> <p>Results</p> <p>The night duties have to be performed under difficult conditions that include working silently in dimmed lighting, and making decisions when fatigue threatens. According to the night staff, its main goals are to provide the patients with rest and simultaneously ensure qualified care. Furthermore, the night nursing staff must prepare the ward for the daytime activities.</p> <p>Conclusion</p> <p>The most important point is the team work, which developed between the registered and enrolled nurses and how necessary this team work is when working at night. In order for nurses working at night to be fully appreciated, the communication between day and night staff in health care organizations needs to be developed. Furthermore, it is important to give the night staff opportunities to use its whole field of competence.</p
Systematic Review of Potential Health Risks Posed by Pharmaceutical, Occupational and Consumer Exposures to Metallic and Nanoscale Aluminum, Aluminum Oxides, Aluminum Hydroxide and Its Soluble Salts
Aluminum (Al) is a ubiquitous substance encountered both naturally (as the third most abundant element) and intentionally (used in water, foods, pharmaceuticals, and vaccines); it is also present in ambient and occupational airborne particulates. Existing data underscore the importance of Al physical and chemical forms in relation to its uptake, accumulation, and systemic bioavailability. The present review represents a systematic examination of the peer-reviewed literature on the adverse health effects of Al materials published since a previous critical evaluation compiled by Krewski et al. (2007).
Challenges encountered in carrying out the present review reflected the experimental use of different physical and chemical Al forms, different routes of administration, and different target organs in relation to the magnitude, frequency, and duration of exposure. Wide variations in diet can result in Al intakes that are often higher than the World Health Organization provisional tolerable weekly intake (PTWI), which is based on studies with Al citrate. Comparing daily dietary Al exposures on the basis of âtotal Alâassumes that gastrointestinal bioavailability for all dietary Al forms is equivalent to that for Al citrate, an approach that requires validation. Current occupational exposure limits (OELs) for identical Al substances vary as much as 15-fold.
The toxicity of different Al forms depends in large measure on their physical behavior and relative solubility in water. The toxicity of soluble Al forms depends upon the delivered dose of Al+ 3 to target tissues. Trivalent Al reacts with water to produce bidentate superoxide coordination spheres [Al(O2)(H2O4)+ 2 and Al(H2O)6 + 3] that after complexation with O2âąâ, generate Al superoxides [Al(O2âą)](H2O5)]+ 2. Semireduced AlO2âą radicals deplete mitochondrial Fe and promote generation of H2O2, O2 âą â and OHâą. Thus, it is the Al+ 3-induced formation of oxygen radicals that accounts for the oxidative damage that leads to intrinsic apoptosis. In contrast, the toxicity of the insoluble Al oxides depends primarily on their behavior as particulates.
Aluminum has been held responsible for human morbidity and mortality, but there is no consistent and convincing evidence to associate the Al found in food and drinking water at the doses and chemical forms presently consumed by people living in North America and Western Europe with increased risk for Alzheimer\u27s disease (AD). Neither is there clear evidence to show use of Al-containing underarm antiperspirants or cosmetics increases the risk of AD or breast cancer. Metallic Al, its oxides, and common Al salts have not been shown to be either genotoxic or carcinogenic. Aluminum exposures during neonatal and pediatric parenteral nutrition (PN) can impair bone mineralization and delay neurological development. Adverse effects to vaccines with Al adjuvants have occurred; however, recent controlled trials found that the immunologic response to certain vaccines with Al adjuvants was no greater, and in some cases less than, that after identical vaccination without Al adjuvants.
The scientific literature on the adverse health effects of Al is extensive. Health risk assessments for Al must take into account individual co-factors (e.g., age, renal function, diet, gastric pH). Conclusions from the current review point to the need for refinement of the PTWI, reduction of Al contamination in PN solutions, justification for routine addition of Al to vaccines, and harmonization of OELs for Al substances
Delirium Risk Factors in Elderly Hospitalized Patients
OBJECTIVE: Delirium is frequent in elderly hospitalized patients. Many studies have examined its risk factors, but results have been quite variable. Thus, the goal of this study is to identify through systematic literature review the risk factors associated with the development of delirium in hospitalized geriatric patients. MEASUREMENTS AND MAIN RESULTS: First, medline/current contentsdatabases were screened for relevant articles published from 1966 to December 1995, and from bibliographies of identified articles additional reports were selected. Second, the reports were screened by two different investigators and retained only if meeting the five following criteria: (1) original research in French or English; (2) prospective study; (3) patients over age 50; (4) minimum of one risk factor examined; (5) acceptable definition of delirium. Third, the methodology of each study was graded according to specific criteria for risk factor studies. Fourth, risk factors were identified and tabulated, unadjusted odds ratios (ORs) were computed, and where appropriate a combined OR with the Mantel-Haenszel estimator was calculated. Twenty-seven articles were retained meeting all of the above criteria. Among these studies, 11 were done on medical patients, 9 on surgical patients, 2 on medical and surgical patients, and 5 on psychiatric patients. In total 1,365 subjects with delirium were studied. Sixty-one different risk factors were examined, the five most common being dementia, medication, medical illness, age, and male gender. Mantel-Haenszel estimator was calculated for 10 risk factors, the most strongly associated being dementia (OR 5.2; 95% confidence interval [CI] 4.2, 6.3), medical illness (OR 3.8; 95% CI 2.2, 6.4), alcohol abuse (OR 3.3; 95% CI 1.9, 5.5), and depression (OR 1.9; 95% CI 1.3, 2.6). Methodologic weaknesses were present in many studies. CONCLUSIONS: Despite methodologic limitations, certain risk factors for delirium seem to be consistent and could help identify high-risk patients. These risk factors include dementia, advanced age, and medical illness. Other risk factors appear to play a contributory role in the development of delirium in elderly hospitalized patients