Unconventional Low-Cost Fabrication and Patterning Techniques for Point of Care Diagnostics

The potential of rapid, quantitative, and sensitive diagnosis has led to many innovative ‘lab on chip’ technologies for point of care diagnostic applications. Because these chips must be designed within strict cost constraints to be widely deployable, recent research in this area has produced extremely novel non-conventional micro- and nano-fabrication innovations. These advances can be leveraged for other biological assays as well, including for custom assay development and academic prototyping. The technologies reviewed here leverage extremely low-cost substrates and easily adoptable ways to pattern both structural and biological materials at high resolution in unprecedented ways. These new approaches offer the promise of more rapid prototyping with less investment in capital equipment as well as greater flexibility in design. Though still in their infancy, these technologies hold potential to improve upon the resolution, sensitivity, flexibility, and cost-savings over more traditional approaches.     

Characterization of the anticancer properties of monoglycosidic cardenolides isolated from Nerium oleander and Streptocaulon tomentosum

Aim of the study

For identification of the active constituents we investigated the anticancer activity of cardenolides from Streptocaulon tomentosum Wight & Arn. (Asclepiadaceae) and from Nerium oleander L. (Apocynaceae) which are both used against cancer in the traditional medicine in their region of origin.

Material, methods and results

The antiproliferative activity of cardenolides isolated from roots of Streptocaulon tomentosum (IC₅₀ < 1-15.3 μM after 2 days in MCF7) and of cardenolide containing fractions from the cold aqueous extract of Nerium oleander leaves (“Breastin”, mean IC₅₀ 0.85 μg/ml in a panel of 36 human tumor cell lines), their influence on the cellular viability and on the cell cycle (block at the G2/M-phase or at the S-phase in tumor cells, respectively) were determined using different cell lines. The murine cell line L929 and normal non-tumor cells were not affected. Bioactivity guided fractionation of Breastin resulted in the isolation of the monoglycosidic cardenolides oleandrine, oleandrigeninsarmentoside, neritaloside, odoroside H, and odoroside A (IC₅₀-values between 0.010 and 0.071 μg/ml).

Conclusions

The observed anticancer activities of extracts and isolated cardenolides are in agreement with the ethnomedicinal use of Streptocaulon tomentosum and Nerium oleander. The most active anticancer compounds from both species are monoglycosidic cardenolides possessing the 3β,14β-dihydroxy-5β-card-20(22)-enolide structure with or without an acetoxy group at C-16. The results indicate that the cytotoxic effects are induced by the inhibition of the plasma membrane bound Na⁺/K⁺-ATPase.     

Oculomotor and neuropsychological effects of antipsychotic treatment for schizophrenia

Cognitive enhancement has become an important target for drug therapies in schizophrenia. Treatment development in this area requires assessment approaches that are sensitive to procognitive effects of antipsychotic and adjunctive treatments. Ideally, new treatments will have translational characteristics for parallel human and animal research. Previous studies of antipsychotic effects on cognition have relied primarily on paper-and-pencil neuropsychological testing. No study has directly compared neurophysiological biomarkers and neuropsychological testing as strategies for assessing cognitive effects of antipsychotic treatment early in the course of schizophrenia. Antipsychotic-naive patients with schizophrenia were tested before treatment with risperidone and again 6 weeks later. Matched healthy participants were tested over a similar time period. Test-retest reliability, effect sizes of within-subject change, and multivariate/univariate analysis of variance were used to compare 3 neurophysiological tests (visually guided saccade, memory-guided saccade, and antisaccade) with neuropsychological tests covering 4 cognitive domains (executive function, attention, memory, and manual motor function). While both measurement approaches showed robust neurocognitive impairments in patients prior to risperidone treatment, oculomotor biomarkers were more sensitive to treatment-related effects on neurocognitive function than traditional neuropsychological measures. Further, unlike the pattern of modest generalized cognitive improvement suggested by neuropsychological measures, the oculomotor findings revealed a mixed pattern of beneficial and adverse treatment-related effects. These findings warrant further investigation regarding the utility of neurophysiological biomarkers for assessing cognitive outcomes of antipsychotic treatment in clinical trials and in early-phase drug development.     

Correction to: Pathology-supported genetic testing as a method for disability prevention in multiple sclerosis (MS). Part II. Insights from two MS cases

Metabolic Brain Disease - A Correction to this paper has been published: https://doi.org/10.1007/s11011-021-00722-7     

Seat belt use by children brought to an inner-city hospital.

OBJECTIVE: To characterize restraint use among children brought to an inner-city hospital by private car or taxicab. DESIGN: Cross-sectional survey and direct observation of a convenience sample. SETTING: Main entrance and clinic entrance of a large urban public hospital. PARTICIPANTS: Direct observation was made on 352 children brought by 257 vehicles. One hundred seventy-seven parents or caretakers responded to questionnaires for 240 children. INTERVENTION: None. MEASURES AND MAIN RESULTS: Of the 352 children who were directly observed, 256 (73%) arrived by taxicabs and 96 (27%) by private cars. Thirty-three of 352 (9%) children were observed to be appropriately restrained. Children brought by taxicabs were significantly less likely to be restrained than children brought by private cars (1% vs 31%, P < 0.001). Caretakers reported that seat belts were available in 46 of 54 (85%) private cars, compared to 38 of 88 (43%) taxicabs (P < 0.01). Twenty percent of caretakers who came by taxicabs did not check for seat belts. CONCLUSION: Taxicabs, which are exempt from the New York State's mandatory seat belt law, are a common mode of transportation for children in the inner city. While the overall use of child restraints in the study sample is low, it is particularly low for children in taxicabs. The low rate may be related to both the decreased availability of seat belts and the lack of the mandatory seat belt law for taxicabs. Strategies should be sought to improve child restraint availability in taxicabs and mandate seat belt use.     

Electrophoresis-assisted single-cell electroporation for efficient intracellular delivery

Single-cell electroporation, in which a focused electric field is applied to permeabilize an individual target cell using relatively low applied voltages, has demonstrated improved cell viability and transfection rates over conventional bulk electroporation set-ups. Here, we introduce a new strategy, in conjunction with single-cell electroporation, to enhance exogenous transport efficiency: electrophoresis delivery of compounds subsequent to electroporation. Electrophoresis is used to assist loading of otherwise impermeable exogenous anionic fluorescent molecules Calcein (Invitrogen, MW = 622) and Oregon Green Dextran (OGD, Invitrogen, MW = 70,000). For the larger dextran molecules, we demonstrate a protocol of first pre-concentrating at the cell-microfluidic channel interface. Then, the electric field is used to drive these molecules into the cell post-electroporation using 50–200 mV. We demonstrate delivery rate enhancements of more than an order of magnitude using electrophoresis compared to diffusion alone subsequent to electroporation.