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Principles of appropriate antibiotic use for treatment of uncomplicated acute bronchitis: background.
The following principles of appropriate antibiotic use for adults with acute bronchitis apply to immunocompetent adults without complicating comorbid conditions, such as chronic lung or heart disease. The evaluation of adults with an acute cough illness or a presumptive diagnosis of uncomplicated acute bronchitis should focus on ruling out serious illness, particularly pneumonia. In healthy, nonelderly adults, pneumonia is uncommon in the absence of vital sign abnormalities or asymmetrical lung sounds, and chest radiography is usually not indicated. In patients with cough lasting 3 weeks or longer, chest radiography may be warranted in the absence of other known causes. Routine antibiotic treatment of uncomplicated acute bronchitis is not recommended, regardless of duration of cough. If pertussis infection is suspected (an unusual circumstance), a diagnostic test should be performed and antimicrobial therapy initiated. Patient satisfaction with care for acute bronchitis depends most on physician--patient communication rather than on antibiotic treatment
A Visual Metaphor Describing Neural Dynamics in Schizophrenia
Background: In many scientific disciplines the use of a metaphor as an heuristic aid is not uncommon. A well known example in somatic medicine is the 'defense army metaphor' used to characterize the immune system. In fact, probably a large part of the everyday work of doctors consists of 'translating' scientific and clinical information (i.e. causes of disease, percentage of succes versus risk of side-effects) into information tailored to the needs and capacities of the individual patient. The ability to do so in an effective way is at least partly what makes a clinician a good communicator. Schizophrenia is a severe psychiatric disorder which affects approximately 1% of the population. Over the last two decades a large amount of molecular-biological, imaging and genetic data have been accumulated regarding the biological underpinnings of schizophrenia. However, it remains difficult to understand how the characteristic symptoms of schizophrenia such as hallucinations and delusions are related to disturbances on the molecular-biological level. In general, psychiatry seems to lack a conceptual framework with sufficient explanatory power to link the mental- and molecular-biological domains. Methodology/Principal Findings: Here, we present an essay-like study in which we propose to use visualized concepts stemming from the theory on dynamical complex systems as a 'visual metaphor' to bridge the mental- and molecular-biological domains in schizophrenia. We first describe a computer model of neural information processing; we show how the information processing in this model can be visualized, using concepts from the theory on complex systems. We then describe two computer models which have been used to investigate the primary theory on schizophrenia, the neurodevelopmental model, and show how disturbed information processing in these two computer models can be presented in terms of the visual metaphor previously described. Finally, we describe the effects of dopamine neuromodulation, of which disturbances have been frequently described in schizophrenia, in terms of the same visualized metaphor. Conclusions/Significance: The conceptual framework and metaphor described offers a heuristic tool to understand the relationship between the mental- and molecular-biological domains in an intuitive way. The concepts we present may serve to facilitate communicatio
Pathological and ecological host consequences of infection by an introduced fish parasite
The infection consequences of the introduced cestode fish parasite Bothriocephalus acheilognathi were studied in a cohort of wild, young-of-the-year common carp Cyprinus carpio that lacked co-evolution with the parasite. Within the cohort, parasite prevalence was 42% and parasite burdens were up to 12% body weight. Pathological changes within the intestinal tract of parasitized carp included distension of the gut wall, epithelial compression and degeneration, pressure necrosis and varied inflammatory changes. These were most pronounced in regions containing the largest proportion of mature proglottids. Although the body lengths of parasitized and non-parasitized fish were not significantly different, parasitized fish were of lower body condition and reduced weight compared to non-parasitized conspecifics. Stable isotope analysis (δ15N and δ13C) revealed trophic impacts associated with infection, particularly for δ15N where values for parasitized fish were significantly reduced as their parasite burden increased. In a controlled aquarium environment where the fish were fed ad libitum on an identical food source, there was no significant difference in values of δ15N and δ13C between parasitized and non-parasitized fish. The growth consequences remained, however, with parasitized fish growing significantly slower than non-parasitized fish, with their feeding rate (items s−1) also significantly lower. Thus, infection by an introduced parasite had multiple pathological, ecological and trophic impacts on a host with no experience of the parasite
The Influence of Abacavir and Other Antiretroviral Agents on Virological Response to HCV Therapy Among Antiretroviral-Treated HIV-Infected Patients.
BACKGROUND: It remains unclear if certain antiretroviral medications, particularly abacavir, compromise response to HCV therapy. Such data could inform the selection of appropriate antiretrovirals in HIV/HCV-coinfected patients. The aim of this study was to determine if use of abacavir, as well as other antiretrovirals, was associated with reduced response to pegylated interferon (PEG-IFN) plus ribavirin.
METHODS: A cohort study was performed among antiretroviral-treated HIV/HCV-coinfected patients initiating PEG-IFN plus ribavirin between January 2001 and June 2007 at six sites in the United States. Abacavir and other antiretrovirals represented exposures of interest. Study outcomes included an early virological response (\u3e or =2 log IU/ml decrease in HCV viral load at 12 weeks) and sustained virological response (undetectable HCV viral load 24 weeks after treatment discontinuation).
RESULTS: Among 212 patients, 74 (35%) received abacavir. For patients infected with HCV genotype 1 or 4, no differences were observed between abacavir users and non-users in early virological response (26 [40%] versus 53 [44%]; adjusted odds ratio [OR] 1.00; 95% confidence interval [CI] 0.50-2.00) or sustained virological response (8 [13%] versus 13 [12%]; adjusted OR 1.34; 95% CI 0.50-3.62). Among genotype 2 and 3 patients, rates of early virological response (7 [78%] versus 16 [89%]; OR 0.44; 95% CI 0.05-3.76) and sustained virological response (3 [33%] versus 8 [44%]; OR 0.63; 95% CI 0.12-3.32) were also similar between abacavir users and non-users. No association was found between other antiretrovirals and a lack of early or sustained response.
CONCLUSIONS: Use of abacavir or other antiretroviral medications was not associated with reduced early or sustained virological response rates
Successful Internalization of a Chronic Biliary Cutaneous Fistula After Liver Transplantation: Deepithelializing the Fistula Tract
Biliary cutaneous fistulas are uncommon sequelae after biliary surgery and can be a source of significant morbidity. We describe a liver recipient who developed a biliary cutaneous fistula secondary to hepatic artery thrombosis; this subsequently drained for over 7 years. Through a novel approach, using the transabdominal fistula tract as a conduit, the fistula skin opening was deepithelialized and anastomosed to a jejunal loop, internally draining the tract. For over 7 years postoperatively, this internal drainage procedure has continued to function effectively. This approach may have value in internalizing longstanding biliary cutaneous fistulas in well-selected patients in whom there is no existing biliary ductal system or the existing system anatomically does not lend itself to restoration of functional internal drainage through conventional approaches
Wegner on Hallucinations, Inconsistency, and the Illusion of Free Will. Some Critical Remarks
Wegner's argument on the illusory nature of conscious will, as developed in The Illusion of Conscious Will (2002) and other publications, has had major impact. Based on empirical data, he develops a theory of apparent mental causation in order to explain the occurrence of the illusion of conscious will. Part of the evidence for his argument is derived from a specific interpretation of the phenomenon of auditory verbal hallucinations as they may occur in schizophrenia. The aim of this paper is to evaluate the validity of the evidence on auditory verbal hallucinations as employed by Wegner. I conclude that auditory hallucinations do not provide solid evidence for Wegner's theory. Moreover, the phenomena in schizophrenia provide, in fact, an argument against part of Wegner's theory of apparent mental causation. © 2010 The Author(s)
Design of a placebo-controlled, randomized study of the efficacy of repetitive transcranial magnetic stimulation for the treatment of chronic tinnitus
Structure formation in active networks
Structure formation and constant reorganization of the actin cytoskeleton are
key requirements for the function of living cells. Here we show that a minimal
reconstituted system consisting of actin filaments, crosslinking molecules and
molecular-motor filaments exhibits a generic mechanism of structure formation,
characterized by a broad distribution of cluster sizes. We demonstrate that the
growth of the structures depends on the intricate balance between
crosslinker-induced stabilization and simultaneous destabilization by molecular
motors, a mechanism analogous to nucleation and growth in passive systems. We
also show that the intricate interplay between force generation, coarsening and
connectivity is responsible for the highly dynamic process of structure
formation in this heterogeneous active gel, and that these competing mechanisms
result in anomalous transport, reminiscent of intracellular dynamics
Comparison of breast and bowel cancer screening uptake patterns in a common cohort of South Asian women in England
Background: Inequalities in uptake of cancer screening by ethnic minority populations are well documented in a
number of international studies. However, most studies to date have explored screening uptake for a single cancer
only. This paper compares breast and bowel cancer screening uptake for a cohort of South Asian women invited to
undertake both, and similarly investigates these women's breast cancer screening behaviour over a period of fifteen
years.
Methods: Screening data for rounds 1, 2 and 5 (1989-2004) of the NHS breast cancer screening programme and for
round 1 of the NHS bowel screening pilot (2000-2002) were obtained for women aged 50-69 resident in the English
bowel screening pilot site, Coventry and Warwickshire, who had been invited to undertake breast and bowel cancer
screening in the period 2000-2002. Breast and bowel cancer screening uptake levels were calculated and compared
using the chi-squared test.
Results: 72,566 women were invited to breast and bowel cancer screening after exclusions. Of these, 3,539 were South
Asian and 69,027 non-Asian; 18,730 had been invited to mammography over the previous fifteen years (rounds 1 to 5).
South Asian women were significantly less likely to undertake both breast and bowel cancer screening; 29.9% (n =
1,057) compared to 59.4% (n = 40,969) for non-Asians (p < 0.001). Women in both groups who consistently chose to
undertake breast cancer screening in rounds 1, 2 and 5 were more likely to complete round 1 bowel cancer screening.
However, the likelihood of completion of bowel cancer screening was still significantly lower for South Asians; 49.5% vs.
82.3% for non-Asians, p < 0.001. South Asian women who undertook breast cancer screening in only one round were
no more likely to complete bowel cancer screening than those who decided against breast cancer screening in all
three rounds. In contrast, similar women in the non-Asian population had an increased likelihood of completing the
new bowel cancer screening test. The likelihood of continued uptake of mammography after undertaking screening in
round 1 differed between South Asian religio-linguistic groups. Noticeably, women in the Muslim population were less
likely to continue to participate in mammography than those in other South Asian groups.
Conclusions: Culturally appropriate targeted interventions are required to reduce observed disparities in cancer
screening uptakes
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