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71.

Background

Fracture of the femur is the most frequent late complication in patients with soft tissue sarcomas (STS) who receive external beam radiotherapy after limb-sparing surgery.

Aim

To reduce the risk of bone fracture following radiotherapy of STS of the thigh, we minimized the dose to the femur and to surrounding normal tissues by applying intensity modulated radiation therapy (IMRT). We report preliminary results of post-surgery IMRT of the thigh in patients with STS in this extremity.

Materials and methods

10 adult patients undergoing post-operative radiotherapy of STS of the thigh were treated using IMRT. Clinical IMRT plans with simultaneous integrated boost (SIB) and 3-phase three-dimensional conformal radiotherapy (3D-CRT) were designed to adequately treat the planning target volume and to spare the femur to the largest extent possible. Dose distributions and dose-volume histograms were compared.

Results

For either technique, a comparable target coverage was achieved; however, target volume was better covered and critical structures were better spared in IMRT plans. Mean and maximum doses to OAR structures were also significantly reduced in the IMRT plans. On average, the mean dose to the femur in 3D-CRT plans was about two times higher than that in IMRT plans.

Conclusion

Compared with 3D-CRT, the application of IMRT improves the dose distribution within the concave target volumes and reduces dose to the OAR structures without compromising target coverage.  相似文献   
72.
73.
Zhao J  Lama M  Sarkar S  Atun R 《PloS one》2011,6(12):e28932

Introduction

In 2010, the Global Fund provided more than 75% of external international financing for malaria control. The Global Fund uses performance based funding in the grants it finances. This paper analyses the indicators used to measure the performance of Global Fund supported malaria grants in Asia.

Methods

Indicators used in the performance frameworks for all Global Fund supported malaria grants in Asia were retrieved from grant database and grouped into impact, outcome, output and input categories and categorized by service delivery areas. Indicators of each group were compared over rounds. Indicators used in performance frameworks were compared with internationally adopted indicators included in the Monitoring and Evaluation Toolkit developed by the Global Fund and international technical agencies.

Results

Between 2002 and 2010, 1,434 indicators were included in the performance frameworks of the 48 malaria grants awarded in Asia, including 229 impact and 227 outcome indicators, 437 output and 541 input indicators, with an average of 29.9 indicators per grant. The proportion of impact and outcome indicators increased over rounds, with that of input indicators declining from 44.1% in Round 1 to 22.7% in Round 9.

Conclusions

Input indicators, which have predominated the performance frameworks of the Global Fund supported malaria programs in Asia have declined between Rounds 1 and 9. However, increased alignment with internationally adopted indicators included in the Monitoring and Evaluation Toolkit is needed to improve the validity of reported results.  相似文献   
74.
Phylogenetic relationships and identification of species of the genus Hypostomus is still unclear. Considering this, cytogenetics may prove itself as an important tool in understanding the systematic of this genus. Reviews in Hypostomus indicate that the diploid number ranges from 54 to 84 chromosomes, and the increase in diploid number has been associated to higher percentages of subtelocentric and acrocentric chromosomes. Although there is a high number of species in the genus, there are relatively few papers concerning Hypostomus cytogenetics, and most of the data is published as grey literature. With the aim to understand the chromosomal evolution in the genus (correlation between diploid number x chromosomes types), H. ancistroides and H. topavae from the Piquiri River, Upper Paraná River basin, were cytogenetically analyzed, and the diploid number observed was 68 and 80 chromosomes, respectively. Additional data on the diploid number and chromosome formulae was compiled from papers (27 analyses) and abstracts from grey literature (77 analyses). Our analysis shows no correlation between chromosome numbers and percentages of subtelocentric and acrocentric chromosomes for most of the species, since there is considerable variation between these percentages even between species with the same diploid number, indicating that the proportion of chromosome types is not always associated to diploid numbers.  相似文献   
75.
76.

Background

Several interventions for tuberculosis (TB) control have been recommended by the World Health Organization (WHO) over the past decade. These include isoniazid preventive therapy (IPT) for HIV-infected individuals and household contacts of infectious TB patients, diagnostic algorithms for rule-in or rule-out of smear-negative pulmonary TB, and programmatic treatment for multidrug-resistant TB. There is no systematically collected data on the type of evidence that is publicly available to guide the scale-up of these interventions in low- and middle-income countries. We investigated the availability of published evidence on their effectiveness, delivery, and cost-effectiveness that policy makers need for scaling-up these interventions at country level.

Methods and Findings

PubMed, Web of Science, EMBASE, and several regional databases were searched for studies published from 1 January 1990 through 31 March 2012 that assessed health outcomes, delivery aspects, or cost-effectiveness for any of these interventions in low- or middle-income countries. Selected studies were evaluated for their objective(s), design, geographical and institutional setting, and generalizability. Studies reporting health outcomes were categorized as primarily addressing efficacy or effectiveness of the intervention. These criteria were used to draw landscapes of published research. We identified 59 studies on IPT in HIV infection, 14 on IPT in household contacts, 44 on rule-in diagnosis, 19 on rule-out diagnosis, and 72 on second-line treatment. Comparative effectiveness studies were relatively few (n = 9) and limited to South America and sub-Saharan Africa for IPT in HIV-infection, absent for IPT in household contacts, and rare for second-line treatment (n = 3). Evaluations of diagnostic and screening algorithms were more frequent (n = 19) but geographically clustered and mainly of non-comparative design. Fifty-four studies evaluated ways of delivering these interventions, and nine addressed their cost-effectiveness.

Conclusions

There are substantial gaps in published evidence for scale-up for five WHO-recommended TB interventions settings at country level, which for many countries possibly precludes program-wide implementation of these interventions. There is a strong need for rigorous operational research studies to be carried out in programmatic settings to inform on best use of existing and new interventions in TB control. Please see later in the article for the Editors'' Summary  相似文献   
77.
78.
The amino terminal dimerization/docking domain and the two-tandem, carboxy-terminal cAMP-binding domains (A and B) of cAMP-dependent protein kinase regulatory (R) subunits are connected by a variable linker region. In addition to providing a docking site for the catalytic subunit, the linker region is a major source of sequence diversity between the R-subunit isoforms. The RIIbeta isoform uniquely contains two endogenous tryptophan residues, one at position 58 in the linker region and the other at position 243 in cAMP-binding domain A, which can act as intrinsic reporter groups of their dynamics and microenvironment. Two single-point mutations, W58F and W243F, allowed the local environment of each Trp to be probed using steady-state and time-resolved fluorescence techniques. We report that: (a) the tryptophan fluorescence of the wild-type protein largely reflects Trp243 emission; (2) cAMP selectively quenches Trp243 and thus acts as a cAMP sensor; (3) Trp58 resides in a highly solvated, unstructured, and mobile region of the protein; and (4) Trp243 resides in a stable, folded domain and is relatively buried and rigid within the domain. The use of endogenous Trp residues presents a non-perturbing method for studying R-subunit subdomain characteristics in addition to providing the first biophysical data on the RIIbeta linker region.  相似文献   
79.
We evaluated the effect of specimen processing variations and quantitation methods on quantitative determination of CD38 expression on CD8 T lymphocytes. Neither lysing reagent (ammonium chloride versus BD FACSlyse), fixation (paraformaldehyde versus no final fixation step), nor acquisition delay (acquisition within 6 h after fixation versus 24 h after fixation) had a significant effect on CD38 relative fluorescent intensity or CD38 quantitative estimates (RFI or antibodies bound per cell). The only significant difference in fluorescent intensity and CD38 antibodies bound per cell (ABC) was encountered when whole blood was held for 24 h prior to staining and fixation and then acquired after another 24-h hold. However, for all sample processing methods above, the CD4 biologic calibrator and QuantiBRITE bead methods gave significantly different estimates of CD38 intensity. In many cases, however, these differences are relatively small and were more pronounced in certain laboratories. We conclude that there is some flexibility in sample processing methods for quantitative CD38 determination; however, it is preferable for a laboratory to employ one method of fluorescence quantitation calculation consistently because small differences are detected between different methods. Cytometry (Comm. Clin. Cytometry) 42:174-179, 2000.  相似文献   
80.
The major surface proteins of the parasitic protozoon Leishmania mexicana are anchored to the plasma membrane by glycosylphosphatidylinositol (GPI) anchors. We have cloned the L. mexicana GPI8 gene that encodes the catalytic component of the GPI:protein transamidase complex that adds GPI anchors to nascent cell surface proteins in the endoplasmic reticulum. Mutants lacking GPI8 (DeltaGPI8) do not express detectable levels of GPI-anchored proteins and accumulate two putative protein-anchor precursors. However, the synthesis and cellular levels of other non-protein-linked GPIs, including lipophosphoglycan and a major class of free GPIs, are not affected in the DeltaGPI8 mutant. Significantly, the DeltaGPI8 mutant displays normal growth in liquid culture, is capable of differentiating into replicating amastigotes within macrophages in vitro, and is infective to mice. These data suggest that GPI-anchored surface proteins are not essential to L. mexicana for its entry into and survival within mammalian host cells in vitro or in vivo and provide further support for the notion that free GPIs are essential for parasite growth.  相似文献   
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