2,293 research outputs found
The morbidity of urethral stricture disease among male Medicare beneficiaries
<p>Abstract</p> <p>Background</p> <p>To date, the morbidity of urethral stricture disease among American men has not been analyzed using national datasets. We sought to analyze the morbidity of urethral stricture disease by measuring the rates of urinary tract infections and urinary incontinence among men with a diagnosis of urethral stricture.</p> <p>Methods</p> <p>We analyzed Medicare claims data for 1992, 1995, 1998, and 2001 to estimate the rate of dual diagnoses of urethral stricture with urinary tract infection and with urinary incontinence occurring in the same year among a 5% sample of beneficiaries. Male Medicare beneficiaries receiving co-incident ICD-9 codes indicating diagnoses of urethral stricture and either urinary tract infection or urinary incontinence within the same year were counted.</p> <p>Results</p> <p>The percentage of male patients with a diagnosis of urethral stricture who also were diagnosed with a urinary tract infection was 42% in 2001, an increase from 35% in 1992. Eleven percent of male Medicare beneficiaries with urethral stricture disease in 2001 were diagnosed with urinary incontinence in the same year. This represents an increase from 8% in 1992.</p> <p>Conclusions</p> <p>Among male Medicare beneficiaries diagnosed with urethral stricture disease in 2001, 42% were also diagnosed with a urinary tract infection, and 11% with incontinence. Although the overall incidence of stricture disease decreased over this time period, these rates of dual diagnoses increased from 1992 to 2001. Our findings shed light into the health burden of stricture disease on American men. In order to decrease the morbidity of stricture disease, early definitive management of strictures is warranted.</p
Inhibition of α9α10 nicotinic acetylcholine receptors prevents chemotherapy-induced neuropathic pain
Opioids are first-line drugs for moderate to severe acute pain and cancer pain. However, these medications are associated with severe side effects, and whether they are efficacious in treatment of chronic nonmalignant pain remains controversial. Medications that act through alternative molecular mechanisms are critically needed. Antagonists of α9α10 nicotinic acetylcholine receptors (nAChRs) have been proposed as an important nonopioid mechanism based on studies demonstrating prevention of neuropathology after trauma-induced nerve injury. However, the key α9α10 ligands characterized to date are at least two orders of magnitude less potent on human vs. rodent nAChRs, limiting their translational application. Furthermore, an alternative proposal that these ligands achieve their beneficial effects by acting as agonists of GABA(B) receptors has caused confusion over whether blockade of α9α10 nAChRs is the fundamental underlying mechanism. To address these issues definitively, we developed RgIA4, a peptide that exhibits high potency for both human and rodent α9α10 nAChRs, and was at least 1,000-fold more selective for α9α10 nAChRs vs. all other molecular targets tested, including opioid and GABA(B) receptors. A daily s.c. dose of RgIA4 prevented chemotherapy-induced neuropathic pain in rats. In wild-type mice, oxaliplatin treatment produced cold allodynia that could be prevented by RgIA4. Additionally, in α9 KO mice, chemotherapy-induced development of cold allodynia was attenuated and the milder, temporary cold allodynia was not relieved by RgIA4. These findings establish blockade of α9-containing nAChRs as the basis for the efficacy of RgIA4, and that α9-containing nAChRs are a critical target for prevention of chronic cancer chemotherapy-induced neuropathic pain
The Classical Harmonic Vibrations of the Atomic Centers of Mass with Micro Amplitudes and Low Frequencies Monitored by the Entanglement between the Two Two-level Atoms in a Single mode Cavity
We study the entanglement dynamics of the two two-level atoms coupling with a
single-mode polarized cavity field after incorporating the atomic centers of
mass classical harmonic vibrations with micro amplitudes and low frequencies.
We propose a quantitative vibrant factor to modify the concurrence of the two
atoms states. When the vibrant frequencies are very low, we obtain that: (i)
the factor depends on the relative vibrant displacements and the initial phases
rather than the absolute amplitudes, and reduces the concurrence to three
orders of magnitude; (ii) the concurrence increases with the increase of the
initial phases; (iii) the frequency of the harmonic vibration can be obtained
by measuring the maximal value of the concurrence during a small time. These
results indicate that even the extremely weak classical harmonic vibrations can
be monitored by the entanglement of quantum states.Comment: 10 pages, 3 figure
Characterization of Leishmania spp. causing cutaneous leishmaniasis in Manaus, Amazonas, Brazil
In the State of Amazonas, American tegumentary leishmaniasis is endemic and presents a wide spectrum of clinical variability due to the large diversity of circulating species in the region. Isolates from patients in Manaus and its metropolitan region were characterized using monoclonal antibodies and isoenzymes belonging to four species of the parasite: Leishmania (Viannia) guyanensis, 73% (153/209); Leishmania (Viannia) braziliensis, 14% (30/209); Leishmania (Leishmania) amazonensis, 8% (17/209); and Leishmania (Viannia) naiffii, 4% (9/209). The most prevalent species was L. (V.) guyanensis. The principal finding of this study was the important quantity of infections involving more than one parasite species, representing 14% (29/209) of the total. The findings obtained in this work regarding the parasite are further highlighted by the fact that these isolates were obtained from clinical samples collected from single lesions
IL-4-secreting CD4+ T cells are crucial to the development of CD8+ T-cell responses against malaria liver stages.
CD4+ T cells are crucial to the development of CD8+ T cell responses against hepatocytes infected with malaria parasites. In the absence of CD4+ T cells, CD8+ T cells initiate a seemingly normal differentiation and proliferation during the first few days after immunization. However, this response fails to develop further and is reduced by more than 90%, compared to that observed in the presence of CD4+ T cells. We report here that interleukin-4 (IL-4) secreted by CD4+ T cells is essential to the full development of this CD8+ T cell response. This is the first demonstration that IL-4 is a mediator of CD4/CD8 cross-talk leading to the development of immunity against an infectious pathogen
Predictability of evolutionary trajectories in fitness landscapes
Experimental studies on enzyme evolution show that only a small fraction of
all possible mutation trajectories are accessible to evolution. However, these
experiments deal with individual enzymes and explore a tiny part of the fitness
landscape. We report an exhaustive analysis of fitness landscapes constructed
with an off-lattice model of protein folding where fitness is equated with
robustness to misfolding. This model mimics the essential features of the
interactions between amino acids, is consistent with the key paradigms of
protein folding and reproduces the universal distribution of evolutionary rates
among orthologous proteins. We introduce mean path divergence as a quantitative
measure of the degree to which the starting and ending points determine the
path of evolution in fitness landscapes. Global measures of landscape roughness
are good predictors of path divergence in all studied landscapes: the mean path
divergence is greater in smooth landscapes than in rough ones. The
model-derived and experimental landscapes are significantly smoother than
random landscapes and resemble additive landscapes perturbed with moderate
amounts of noise; thus, these landscapes are substantially robust to mutation.
The model landscapes show a deficit of suboptimal peaks even compared with
noisy additive landscapes with similar overall roughness. We suggest that
smoothness and the substantial deficit of peaks in the fitness landscapes of
protein evolution are fundamental consequences of the physics of protein
folding.Comment: 14 pages, 7 figure
Wanted dead or alive : high diversity of macroinvertebrates associated with living and ’dead’ Posidonia oceanica matte
The Mediterranean endemic seagrass Posidonia
oceanica forms beds characterised by a dense leaf canopy
and a thick root-rhizome ‘matte’. Death of P. oceanica
shoots leads to exposure of the underlying matte, which
can persist for many years, and is termed ‘dead’ matte.
Traditionally, dead matte has been regarded as a degraded
habitat. To test whether this assumption was
true, the motile macroinvertebrates of adjacent living
(with shoots) and dead (without shoots) matte of
P. oceanica were sampled in four different plots located
at the same depth (5–6 m) in Mellieha Bay, Malta
(central Mediterranean). The total number of species
and abundance were significantly higher (ANOVA;
P<0.05 and P<0.01, respectively) in the dead matte
than in living P. oceanica matte, despite the presence of
the foliar canopy in the latter. Multivariate analysis
(MDS) clearly showed two main groups of assemblages,
corresponding to the two matte types. The amphipods
Leptocheirus guttatus and Maera grossimana, and the
polychaete Nereis rava contributed most to the dissimilarity
between the two different matte types. Several
unique properties of the dead matte contributing to the
unexpected higher number of species and abundance of
motile macroinvertebrates associated with this habitat
are discussed. The findings have important implications
for the conservation of bare P. oceanica matte, which
has been generally viewed as a habitat of low ecological
value.peer-reviewe
Translational Medicine is developing in China: A new venue for collaboration
Translational Medicine is an emerging area comprising multidisciplinary Research from basic sciences to medical applications well summarized by the Bench-to-Beside concept; this entails close collaboration between clinicians and basic scientists across institutes. We further clarified that Translational Medicine should be regarded as a two-way road: Bench-to-Bedside and Bedside-to-Bench, to complement testing of novel therapeutic strategies in humans with feedback understanding of how they respond to them. It is, therefore, critical and important to define and promote Translational Medicine among clinicians, basic Researchers, biotechnologists, politicians, ethicists, sociologists, investors and coordinate these efforts among different Countries, fostering aspects germane only to this type of Research such as, as recently discussed, biotechnology entrepreneurship. Translational Medicine as an inter-disciplinary science is developing rapidly and widely and, in this article, we will place a special emphasis on China
building thermal exergy analysis
The energy and environmental impacts due to energy consumption in the building sector are one of the main topics in the global energy field. A building is an energy system that uses energy sources in order to maintain its functionality and to ensure thermal indoor comfort for its occupants. Exergy analysis is a way to assess the impact of an energy system on the environment. This chapter introduces a model able to describe the interaction between a building and its surroundings from an exergetic point of view. The building is considered as a so-called black box, evaluating the exergy of overall energy and matter fluxes that cross the system boundaries. In this way it is possible to evaluate the exergy balance of the system and particularly the destroyed exergy. The exergy destruction percentage can be understood as a building environmental impact indicator. To illustrate the model and its operating suitability, an existing building was analyzed using the transient simulation software Trnsys. The modeling results show that about 95 % of the exergy used from the building is destroyed and that about 5 % is lost (transferred to the surroundings). This means that this building has very high impact. The model can be applied to assess the effectiveness of different building energy retrofit strategies. Through Trnsys modeling some conventional and advanced retrofit strategies, as well as on-site renewable energy utilization, are analyzed. The chapter presents the main analysis results, showing which of these strategies are able to reduce the building's exergy demand and, hence, the building's impact
Evolving cell models for systems and synthetic biology
This paper proposes a new methodology for the automated design of cell models for systems and synthetic biology. Our modelling framework is based on P systems, a discrete, stochastic and modular formal modelling language. The automated design of biological models comprising the optimization of the model structure and its stochastic kinetic constants is performed using an evolutionary algorithm. The evolutionary algorithm evolves model structures by combining different modules taken from a predefined module library and then it fine-tunes the associated stochastic kinetic constants. We investigate four alternative objective functions for the fitness calculation within the evolutionary algorithm: (1) equally weighted sum method, (2) normalization method, (3) randomly weighted sum method, and (4) equally weighted product method. The effectiveness of the methodology is tested on four case studies of increasing complexity including negative and positive autoregulation as well as two gene networks implementing a pulse generator and a bandwidth detector. We provide a systematic analysis of the evolutionary algorithm’s results as well as of the resulting evolved cell models
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