Outpatient Primary Care Practitioner Access: Sex-Based Preferences

Background: In some innovative outpatient practice models, patients are faced with trade-offs, such as choosing between continuity of care vs quick access to a healthcare practitioner (HCP). Our objective was to assess sex-based differences in visit access preferences at an academic outpatient internal medicine clinic. Methods: A 13-question survey with four discrete choice experiments proposing hypothetical care scenarios was offered to patients over a 6-week period in 2018. Descriptive statistics and chi-squared tests evaluated results by sex for categorical variables, Mann-Whitney rank-sum test for continuous variables, and multivariable models adjusted for age, marital status, education, and income. P-values \u3c 0.05 were statistically significant. Results: A majority of 796 of 1731 (46%) respondents were female (56%) and over age 65 (58.5%). Females were more likely than males to prefer communicating with the same allied health staff (AHS) over receiving a quick response (female 36.3% vs male 28.0%, p=0.0031) Females prioritized seeing their own provider as opposed to scheduling a convenient appointment for routine care (female 90.2% vs male 85.0%, p =0.028). Multivariable analysis found that females were 6% less likely than males to request the same AHS for communication (95% CI 0.62-1.44), 29% less likely to request the same HCP for yearly physicals (95% CI 0.34 – 1.44), but 3% more likely than men to request an acute visit with the same HCP (95% CI 0.68-1.56) and 13% more likely to request the same HCP for virtual visits (95% CI 0.70-1.81). Conclusion: Sex-based differences in access preferences were identified. Women preferred continuity of care with the same HCP and AHS over ease of scheduling or a quick response, though these preferences appear to be moderated by other factors including age and marital status. Further identification of longitudinal and socioeconomic factors influencing preferences is needed in this era of evolving practice models.https://jdc.jefferson.edu/sexandgenderhealth/1029/thumbnail.jp

Polydimethylsiloxane-LiNbO3 surface acoustic wave micropump devices for fluid control into microchannels.

This paper presents prototypical microfluidic devices made by hybrid microchannels based on piezoelectric LiNbO3 and polydimethylsiloxane. This system enables withdrawing micropumping by acoustic radiation in microchannels. The withdrawing configuration, integrated on chip, is here quantitatively investigated for the first time, and found to be related to the formation and coalescence dynamics of droplets within the microchannel, primed by surface acoustic waves. The growth dynamics of droplets is governed by the water diffusion on LiNbO3, determining the advancement of the fluid front. Observed velocities are up to 2.6 mm s−1 for 30 dBm signals applied to the interdigital transducer, corresponding to tens of nl s−1, and the micropumping dynamics is described by a model taking into account an acoustic power exponentially decaying upon travelling along the microchannel. This straighforward and flexible micropumping approach is particularly promising for the withdrawing of liquids in lab-on-chip devices performing cycling transport of fluids and biochemical reactions

Efficient and gentle delivery of molecules into cells with different elasticity via Progressive Mechanoporation

Intracellular delivery of cargo molecules such as membrane-impermeable proteins or drugs is crucial for cell treatment in biological and medical applications. Recently, microfluidic mechanoporation techniques have enabled transfection of previously inaccessible cells. These techniques create transient pores in the cell membrane by shear-induced or constriction contact-based rapid cell deformation. However, cells deform and recover differently from a given extent of shear stress or compression and it is unclear how the underlying mechanical properties affect the delivery efficiency of molecules into cells. In this study, we identify cell elasticity as a key mechanical determinant of delivery efficiency leading to the development of “progressive mechanoporation” (PM), a novel mechanoporation method that improves delivery efficiency into cells of different elasticity. PM is based on a multistage cell deformation, through a combination of hydrodynamic forces that pre-deform cells followed by their contact-based compression inside a PDMS-based device controlled by a pressure-based microfluidic controller. PM allows processing of small sample volumes (about 20 μL) with high-throughput (>10 000 cells per s), while controlling both operating pressure and flow rate for a reliable and reproducible cell treatment. We find that uptake of molecules of different sizes is correlated with cell elasticity whereby delivery efficiency of small and big molecules is favoured in more compliant and stiffer cells, respectively. A possible explanation for this opposite trend is a different size, number and lifetime of opened pores. Our data demonstrates that PM reliably and reproducibly delivers impermeable cargo of the size of small molecule inhibitors such as 4 kDa FITC-dextran with >90% efficiency into cells of different mechanical properties without affecting their viability and proliferation rates. Importantly, also much larger cargos such as a >190 kDa Cas9 protein–sgRNA complex are efficiently delivered high-lighting the biological, biomedical and clinical applicability of our findings

Efficient and gentle delivery of molecules into cells with different elasticity via Progressive Mechanoporation.

Intracellular delivery of cargo molecules such as membrane-impermeable proteins or drugs is crucial for cell treatment in biological and medical applications. Recently, microfluidic mechanoporation techniques have enabled transfection of previously inaccessible cells. These techniques create transient pores in the cell membrane by shear-induced or constriction contact-based rapid cell deformation. However, cells deform and recover differently from a given extent of shear stress or compression and it is unclear how the underlying mechanical properties affect the delivery efficiency of molecules into cells. In this study, we identify cell elasticity as a key mechanical determinant of delivery efficiency leading to the development of "progressive mechanoporation" (PM), a novel mechanoporation method that improves delivery efficiency into cells of different elasticity. PM is based on a multistage cell deformation, through a combination of hydrodynamic forces that pre-deform cells followed by their contact-based compression inside a PDMS-based device controlled by a pressure-based microfluidic controller. PM allows processing of small sample volumes (about 20 μL) with high-throughput (>10 000 cells per s), while controlling both operating pressure and flow rate for a reliable and reproducible cell treatment. We find that uptake of molecules of different sizes is correlated with cell elasticity whereby delivery efficiency of small and big molecules is favoured in more compliant and stiffer cells, respectively. A possible explanation for this opposite trend is a different size, number and lifetime of opened pores. Our data demonstrates that PM reliably and reproducibly delivers impermeable cargo of the size of small molecule inhibitors such as 4 kDa FITC-dextran with >90% efficiency into cells of different mechanical properties without affecting their viability and proliferation rates. Importantly, also much larger cargos such as a >190 kDa Cas9 protein-sgRNA complex are efficiently delivered high-lighting the biological, biomedical and clinical applicability of our findings

Polyacrylamide Bead Sensors for in vivo Quantification of Cell-Scale Stress in Zebrafish Development

Mechanical stress exerted and experienced by cells during tissue morphogenesis and organ formation plays an important role in embryonic development. While techniques to quantify mechanical stresses in vitro are available, few methods exist for studying stresses in living organisms. Here, we describe and characterize cell-like polyacrylamide (PAAm) bead sensors with well-defined elastic properties and size for in vivo quantification of cell-scale stresses. The beads were injected into developing zebrafish embryos and their deformations were computationally analyzed to delineate spatio-temporal local acting stresses. With this computational analysis-based cell-scale stress sensing (COMPAX) we are able to detect pulsatile pressure propagation in the developing neural rod potentially originating from polarized midline cell divisions and continuous tissue flow. COMPAX is expected to provide novel spatio-temporal insight into developmental processes at the local tissue level and to facilitate quantitative investigation and a better understanding of morphogenetic processes. © 2019, The Author(s)

Late post-operative paraparesis after rib penetration of the spinal canal in a patient with neurofibromatous scoliosis

Rib displacement into the spinal canal is a rare cause of paraplegia or paraparesis in patients affected by neurofibromatous scoliosis. We describe a case of paraparesis in a 14-year-old child affected by neurofibromatous dystrophic kyphoscoliosis, treated with combined posterior and anterior spinal arthrodesis. Seventeen days after the surgical treatment the patient developed clinical signs and symptoms of paraparesis. A CT scan showed the head of the fifth rib protruding into the spinal canal with cord compression. Rib resection and posterior cord decompression were carried out following complete neurological recovery

Correlative all-optical quantification of mass density and mechanics of subcellular compartments with fluorescence specificity

Quantitative measurements of physical parameters become increasingly important for understanding biological processes. Brillouin microscopy (BM) has recently emerged as one technique providing the 3D distribution of viscoelastic properties inside biological samples − so far relying on the implicit assumption that refractive index (RI) and density can be neglected. Here, we present a novel method (FOB microscopy) combining BM with optical diffraction tomography and epifluorescence imaging for explicitly measuring the Brillouin shift, RI, and absolute density with specificity to fluorescently labeled structures. We show that neglecting the RI and density might lead to erroneous conclusions. Investigating the nucleoplasm of wild-type HeLa cells, we find that it has lower density but higher longitudinal modulus than the cytoplasm. Thus, the longitudinal modulus is not merely sensitive to the water content of the sample − a postulate vividly discussed in the field. We demonstrate the further utility of FOB on various biological systems including adipocytes and intracellular membraneless compartments. FOB microscopy can provide unexpected scientific discoveries and shed quantitative light on processes such as phase separation and transition inside living cells

Combined fluorescence, optical diffraction tomography and Brillouin microscopy

Quantitative measurements of physical parameters become increasingly important for understanding biological processes. Brillouin microscopy (BM) has recently emerged as one technique providing the 3D distribution of viscoelastic properties inside biological samples — so far relying on the implicit assumption that refractive index (RI) and density can be neglected. Here, we present a novel method (FOB microscopy) combining BM with optical diffraction tomography and epi-fluorescence imaging for explicitly measuring the Brillouin shift, RI and absolute density with molecular specificity. We show that neglecting the RI and density might lead to erroneous conclusions. Investigating the cell nucleus, we find that it has lower density but higher longitudinal modulus. Thus, the longitudinal modulus is not merely sensitive to the water content of the sample — a postulate vividly discussed in the field. We demonstrate the further utility of FOB on various biological systems including adipocytes and intracellular membraneless compartments. FOB microscopy can provide unexpected scientific discoveries and shed quantitative light on processes such as phase separation and transition inside living cells