Impact of surgical intervention on progression to end-stage renal disease in patients with posterior urethral valve.

Background: Posterior urethral valve patients present with varied presentations at any age of life and have significant associated morbidity and require long-term follow-up and care.

Methods: This was a single-center ambispective cohort study carried out over a period of 2 years. Patient data regarding the symptoms, investigations, interventions, secondary complications were recorded and were followed up regularly during the study till either normalization of their creatinine level which was maintained up to one-year post-fulguration (non-CKD) or progression to end-stage renal disease (ESRD) requiring renal transplant.

Author Correction: Energetic costs regulated by cell mechanics and confinement are predictive of migration path during decision-making.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Energetic costs regulated by cell mechanics and confinement are predictive of migration path during decision-making.

Cell migration during the invasion-metastasis cascade requires cancer cells to navigate a spatially complex microenvironment that presents directional choices to migrating cells. Here, we investigate cellular energetics during migration decision-making in confined spaces. Theoretical and experimental data show that energetic costs for migration through confined spaces are mediated by a balance between cell and matrix compliance as well as the degree of spatial confinement to direct decision-making.

Integration of sample preparation and analysis into an optofluidic chip for multi-target disease detection.

Detection of molecular biomarkers with high specificity and sensitivity from biological samples requires both sophisticated sample preparation and subsequent analysis. These tasks are often carried out on separate platforms which increases required sample volumes and the risk of errors, sample loss, and contamination. Here, we present an optofluidic platform which combines an optical detection section with single nucleic acid strand sensitivity, and a sample processing unit capable of on-chip, specific extraction and labeling of nucleic acid and protein targets in complex biological matrices.

Scalable Spatial-Spectral Multiplexing of Single-Virus Detection Using Multimode Interference Waveguides.

Simultaneous detection of multiple pathogens and samples (multiplexing) is one of the key requirements for diagnostic tests in order to enable fast, accurate and differentiated diagnoses. Here, we introduce a novel, highly scalable, photonic approach to multiplex analysis with single virus sensitivity. A solid-core multimode interference (MMI) waveguide crosses multiple fluidic waveguide channels on an optofluidic chip to create multi-spot excitation patterns that depend on both the wavelength and location of the channel along the length of the MMI waveguide.

Integrated hollow fiber membranes for gas delivery into optical waveguide based photobioreactors.

Compact algal reactors are presented with: (1) closely stacked layers of waveguides to decrease light-path to enable larger optimal light-zones; (2) waveguides containing scatterers to uniformly distribute light; and (3) hollow fiber membranes to reduce energy required for gas transfer. The reactors are optimized by characterizing the aeration of different gases through hollow fiber membranes and characterizing light intensities at different culture densities. Close to 65% improvement in plateau peak productivities was achieved under low light-intensity growth experiments while maintaining 90% average/peak productivity output during 7-h light cycles.

Optimal intensity and biomass density for biofuel production in a thin-light-path photobioreactor.

Production of competitive microalgal biofuels requires development of high volumetric productivity photobioreactors (PBRs) capable of supporting high-density cultures. Maximal biomass density supported by the current PBRs is limited by nonuniform distribution of light as a result of self-shading effects. We recently developed a thin-light-path stacked photobioreactor with integrated slab waveguides that distributed light uniformly across the volume of the PBR.

Stacked optical waveguide photobioreactor for high density algal cultures.

In this work, an ultracompact algal photobioreactor that alleviates the problem of non-optimal light distribution in current algae photobioreactor systems, by incorporating stacked layers of slab waveguides with embedded light scatterers, is presented. Poor light distribution in traditional photobioreactor systems, due to self-shading effects, is responsible for relatively low volumetric productivity. The optimal conditions for operating a 10-layer bioreactor are outlined.

In situ UV disinfection of a waveguide-based photobioreactor.

Compact waveguide-based photobioreactors with high surface area-to-volume ratios and optimum light-management strategies have been developed to achieve high volumetric productivities within algal cultures. The light-managing strategies have focused on optimizing sunlight collection, sunlight filtration, and light delivery throughout the entire bioreactor volume by using light-directing waveguides. In addition to delivering broad-spectrum or monochromatic light for algal growth, these systems present an opportunity for advances in photobioreactor disinfection by using germicidal ultraviolet (UV) light.

Optofluidic opportunities in global health, food, water and energy.

Optofluidics is a rapidly advancing field that utilizes the integration of optics and microfluidics to provide a number of novel functionalities in microsystems. In this review, we discuss how this approach can potentially be applied to address some of the greatest challenges facing both the developing and developed world, including healthcare, food shortages, malnutrition, water purification, and energy. While medical diagnostics has received most of the attention to date, here we show that some other areas can also potentially benefit from optofluidic technology.

Gel-based optical waveguides with live cell encapsulation and integrated microfluidics.

In this Letter, we demonstrate a biocompatible microscale optical device fabricated from agarose hydrogel that allows for encapsulation of cells inside an optical waveguide. This allows for better interaction between the light in the waveguide and biology, since it can interact with the direct optical mode rather than the evanescent field. We characterize the optical properties of the waveguide and further incorporate a microfluidic channel over the optical structure, thus developing an integrated optofluidic system fabricated entirely from agarose gel.