Introduction The intraocular lens (IOL) can be used as a slow-release drug carrier in cataract surgery to alleviate posterior capsular opacification (PCO). The following is a systematic development ...of an IOL using methotrexate and the solvent casting process with poly (lactic-co-glycolic acid) (PLGA) as a carrier polymer. Methods Different solvents for PLGA and methotrexate were tested for dissolution properties and possible damage to the IOL. The required biological concentration of methotrexate was determined in human capsular bags implanted with an IOL. To detect fibrosis, α-SMA, f-actin, and fibronectin were labelled by immunofluorescence staining. Cell proliferation and extracellular matrix contraction were observed in a lens epithelial cell line (FHL-124). Finally, the IOL was designed, and an ocular pharmacokinetic model was used to measure drug release. Results Solvent mixtures were found to allow coating of the IOL with drug and PLGA without damaging it. PCO in the capsular bag model was inhibited above 1 μM methotrexate ( p = 0.02). Proliferation in FHL-124 was significantly reduced above a concentration of 10 nM ( p = 0.04) and matrix contraction at 100 nM ( p = 0.02). The release profile showed a steady state within therapeutic range. Conclusion After determination of the required physicochemical manufacturing conditions, a drug releasing IOL was designed. A favourable release profile in an ocular pharmacokinetics model could be shown.
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NUK, OILJ, SAZU, UKNU, UL, UM, UPUK
INTRODUCTION:Unintended pregnancy remains persistently high in the United States. Few randomized interventions have effectively reduced pregnancy.
METHODS:We conducted a cluster randomized trial in ...40 Planned Parenthood sites, including family planning and abortion, to assess the effect of a clinic-wide training in long-acting reversible contraceptives (LARCs) on patient outcomes. A cohort of 1,500 patients, 18–25 years, who received contraceptive counseling and did not want to become pregnant in the next 12 months, were recruited from intervention and control clinics. Pregnancy was measured over 12 months with questionnaires, pregnancy tests, and medical record review. In blinded intent-to-treat analyses, we used survival analysis with shared frailty for clustered data to measure the intervention effect compared with standard care. The trial was registered with ClinicalTrials.gov and followed CONSORT (Consolidated Standards of Reporting Trials) guidelines.
RESULTS:Participants were similar in baseline characteristics by arm. At enrollment, after counseling, participants in arm 1 were twice as likely to choose a LARC method as those in arm 2 using generalized estimating equation models for clustered data and robust standard errors (odds ratio 2.0, 95% confidence interval CI 1.3–2.9). In family planning settings, pregnancy during the study was lower in arm 1 (7.5%) than in arm 2 (13.8%). Analyses of the intervention effect in a model with an interaction for setting type showed a highly significant effect on reduced pregnancy in family planning settings (hazard ratio 0.5, 95% CI 0.3–0.8). However, there were no significant differences in pregnancy by arm in the abortion setting.
CONCLUSIONS:A half-day replicable LARC intervention effectively reduced pregnancy in family planning clinics.
CONTEXT: Low knowledge of long-acting reversible contraceptives (LARC) and restrictive counseling practices have been documented among contraceptive care clinicians. However, little is known about ...health educators' counseling on LARC, how their practices compare with clinicians' and their specific training needs. METHODS: A survey conducted in 2011–2012 assessed knowledge and practices related to LARC counseling and provision among 410 staff at 40 Planned Parenthood clinics. Clinicians' and health educators' knowledge and practices were compared via chi-square tests; use of evidence-based criteria was assessed in multivariable logistic regression analyses. RESULTS: At least half of both types of staff routinely discussed LARC with clients, and nearly all considered the methods safe. Health educators considered a smaller proportion of clients candidates for LARC than did clinicians (57% vs. 77%), and they were less likely to consider IUDs for teenagers (79% vs. 96%), nulliparous women (82% vs. 98%) and unmarried clients (90% vs. 99%). In a multivariable model, health educators were less likely than clinicians to counsel clients using the least restrictive evidence-based criteria (odds ratio, 0.1). Sixty-four percent of health educators and 40% of clinicians desired additional LARC training. CONCLUSION: Even in clinics that specialize in reproductive health care, health educators are less likely than clinicians to apply current evidence-based criteria in counseling about LARC. To provide evidence-based contraceptive counseling, health educators need training on LARC eligibility and indications.
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BFBNIB, DOBA, FZAB, GIS, IJS, INZLJ, IZUM, KILJ, NLZOH, NMLJ, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ, ZRSKP
In this paper, we investigate lower bounds of optical-signal-to-noise ratio (OSNR) for three types of electronic digital-signal-processing (DSP) receivers, which are used for an intensity-modulated ...and direct-photo-detected optical transmission link. Target is to determine the performance bound of this transmission link if equalization and/or forward error correction (FEC) are used. The investigated DSP methods are hard-input FEC decoding, soft-input FEC decoding, and sequence detection. The impact of chromatic and polarization mode dispersion, as well as the effect of code rate on the bounds, is shown. Signal statistics are computed analytically. Several implementations of coding and detection schemes, such as Reed-Solomon (RS) and low-density parity-check (LDPC) decoding as well as Turbo equalization, are investigated, and we show the distance of their performances to the derived bounds in quite some detail.
This paper investigates the performance of iterative (turbo) equalization to mitigate the effects of a polarization-mode dispersion (PMD) in nonreturn-to-zero (NRZ) intensity-modulated optical-fiber ...transmission systems. A PMD can lead to severe distortions in the received electrical signal and is a key limiter for the development of high-bit-rate transmission over currently used fibers. In order to reduce the distortions due to a PMD, the performance of symbol-by-symbol maximum a posteriori (sbs-MAP) soft-in/soft-out (SISO) decoders is studied. The SISO algorithms are adapted to the noise statistics of the optical channel where the photo detector leads to a non-Gaussian signal-dependent noise at the receiver side. The modified SISO algorithms are successfully employed for turbo equalization and results show that iterative (turbo) equalization and decoding for the compensation of a PMD can lead to a tremendous reduction in the bit error ratio (BER). Moreover, it is shown that, due to the robustness of mutual information, the extrinsic information transfer (EXIT) chart can be applied for the design of iterative receivers in optical transmission systems even with a non-Gaussian noise
This paper presents a 3 Gbit/s transmission scheme for an automobile optical physical layer, which is based on plastic optical fibers (POF) and low cost light emitting diodes (LED). Tomlinson ...Harashima Precoding (THP) and an adaptive feedforward equalizer (FFE) are used to cope with the strong inter-symbol-interference (ISI). By computer simulations, the system is proven to be a cost-effective and reliable solution for high-speed in-car communications.
We analytically derive probability density functions of the sampled electrically filtered photo current for optical amplitude-shift keying and differential binary phase-shift keying using the ...Karhunen-Loe/spl grave/ve series expansion method. This allows us to determine exact branch metrics for a Viterbi equalizer. We then compare the performance of histogram-based Viterbi equalizers with those using analytically calculated branch metrics.
