ANDeS: An automated nanoliter droplet selection and collection device.

The Droplet Microarray (DMA) has emerged as a tool for high-throughput biological and chemical applications by enabling miniaturization and parallelization of experimental processes. Due to its ability to hold hundreds of nanoliter droplets, the DMA enables simple screening and analysis of samples such as cells and biomolecules. However, handling of nanoliter volumes poses a challenge, as manual recovery of nanoliter volumes is not feasible, and traditional laboratory equipment is not suited to work with such low volumes, and small array formats. To tackle this challenge, we developed the Automated Nanoliter Droplet Selection device (ANDeS), a robotic system for automated collection and transfer of nanoliter samples from DMA. ANDeS can automatically collect volumes from 50 to 350 nL from the flat surface of DMA with a movement accuracy of ±30 µm using fused silica capillaries. The system can automatically collect and transfer the droplets from DMA chip into other platforms, such as microtiter plates, conical tubes or another DMA. In addition, to ensure high throughput and multiple droplet collection, the uptake of multiple droplets within a single capillary, separated by air gaps to avoid mixing of the samples within the capillary, was optimized and demonstrated. This study shows the potential of ANDeS in laboratory applications by using it for the collection and transfer of biological samples, contained in nanoliter droplets, for subsequent analysis. The experimental results demonstrate the ability of ANDeS to increase the versatility of the DMA platform by allowing for automated retrieval of nanoliter samples from DMA, which was not possible manually on the level of individual droplets. Therefore, it widens the variety of analytical techniques that can be used for the analysis of content of individual droplets and experiments performed using DMA. Thus, ANDeS opens up opportunities to expand the development of miniaturized assays in such fields as cell screening, omics analysis and combinatorial chemistry.

Investigation of composition, antioxidant, antimicrobial and cytotoxic characteristics from Juniperus sabina and Ferula communis extracts.

Plants have been one the most valuable sources of biologically active compounds. This study investigates the chemical composition, as well as the antioxidant, antimicrobial, and cytotoxic activities of methanolic and ethanolic extracts from Juniperus sabina and Ferula communis leaves, grown in Cyprus. Total phenolic and flavonoids content of methanol and ethanol extracts were quantified. Chemical constituents of the leaf extracts were analysed using gas chromatography/mass spectrometry (GC/MS). Mome inositol was the predominant component in the J. Sabina's extracts. The most dominant component in F. communis ethanolic extract was phytol, while in FCL methanolic extract 1,3,4,5 tetrahydroxycyclohexanecarboxylic acid. Antioxidant activities were evaluated by 1, 1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging ability. Antioxidant activity results revealed concentration dependent activity for methanolic and ethanolic extracts from the plant leaves. Antibacterial activity of plant extracts was tested against Gram-negative and Gram-positive bacteria using disk diffusion and minimal inhibitory concentration methods. Cytotoxic activity of plant extracts were evaluated on MCF-7 and MDA-MB-231 breast cancer cell lines, where they demonstrated their potential on the viability of both cell lines. The biological activity revealed by plants is due to the bioactive compounds found in the extracts. These bioactive components could be used as anticancer drug candidates.

Automated high-throughput image processing as part of the screening platform for personalized oncology.

Cancer is a devastating disease and the second leading cause of death worldwide. However, the development of resistance to current therapies is making cancer treatment more difficult. Combining the multi-omics data of individual tumors with information on their in-vitro Drug Sensitivity and Resistance Test (DSRT) can help to determine the appropriate therapy for each patient. Miniaturized high-throughput technologies, such as the droplet microarray, enable personalized oncology. We are developing a platform that incorporates DSRT profiling workflows from minute amounts of cellular material and reagents. Experimental results often rely on image-based readout techniques, where images are often constructed in grid-like structures with heterogeneous image processing targets. However, manual image analysis is time-consuming, not reproducible, and impossible for high-throughput experiments due to the amount of data generated. Therefore, automated image processing solutions are an essential component of a screening platform for personalized oncology. We present our comprehensive concept that considers assisted image annotation, algorithms for image processing of grid-like high-throughput experiments, and enhanced learning processes. In addition, the concept includes the deployment of processing pipelines. Details of the computation and implementation are presented. In particular, we outline solutions for linking automated image processing for personalized oncology with high-performance computing. Finally, we demonstrate the advantages of our proposal, using image data from heterogeneous practical experiments and challenges.

Emerging and investigational targeted chemotherapy and immunotherapy agents for metastatic brain tumors.

INTRODUCTION: Metastases to the central nervous system are the most common cause of malignant intracranial tumors in adults. Current standard of care includes surgery and radiation, but overall survival remains poor. A range of systemic therapies are emerging as promising treatment options for these patients. AREAS COVERED: This study reviews novel drug regimens that are under investigation in phase 1 and 2 clinical trials. To identify relevant therapies under clinical investigation, a search was performed on http://clinicaltrials.gov and Pubmed with the keywords brain metastasis, Phase I clinical trial, and Phase II clinical trial from 2016 to 2020. The authors detail the mechanisms of action of all trial agents, outline evidence for their utility, and summarize the current state of the field. EXPERT OPINION: Current advancements in the medical management of brain metastases can be categorized into targeted therapies, methods of overcoming treatment resistance, novel combinations of therapies, and modulation of the tumor microenvironment with a specific focus on immunotherapy. Each of these realms holds great promise for the field going forward. A more streamlined structure for enrollment into clinical trials will be a crucial step in accelerating progress in this area.

Impact of Insurance and Practice Type on Access to Orthopaedic Sports Medicine.

BACKGROUND: The Patient Protection Affordable Care Act has expanded Medicaid eligibility in recent years. However, the provisions of the act have not translated to improved Medicaid payments for specialists such as orthopaedic surgeons. The number of health care practitioners who accept Medicaid is already decreasing, with low reimbursement rates being cited as the primary reason for the trend. HYPOTHESIS: Private practice orthopaedic groups will see patients with Medicaid or Medicare at lower rates than academic orthopaedic practices, and business days until appointment availability will be higher for patients with Medicaid and Medicare than those with private insurance. STUDY DESIGN: Cross-sectional study. METHODS: Researchers made calls to 2 regular-sized orthopaedic practices, 1 small orthopaedic practice, and 1 academic orthopaedic practice in each of the 50 states in the United States. Callers described a scenario of a recent injury resulting in a bucket-handle meniscal tear and an anterior cruciate ligament tear seen on magnetic resonance imaging at an outside emergency department. For a total of 194 practices, 3 separate telephone calls were made, each with a different insurance type. Data regarding insurance acceptance and business days until appointment were tabulated. Student t tests or analysis of variance for continuous data and χ2 or Fisher exact tests for categorical data were utilized. RESULTS: After completing 582 telephone calls, it was determined that 31.4% (n = 59) did not accept Medicaid, compared with 2.2% (n = 4) not accepting Medicare and 1% (n = 1) not accepting private insurance (P < .001). There was no significant association between type of practice and Medicaid refusal (P = 0.12). Mean business days until appointment for Medicaid, Medicare, and private insurance were 5.3, 4.1, and 2.9, respectively (P < .001). CONCLUSIONS: Access to care remains a significant burden for the Medicaid population, given a rate of Medicaid refusal of 32.2% across regular-sized orthopaedic practices. If Medicaid is accepted, time until appointment was significantly longer when compared with private insurance.

Evaluation of Heterotopic Ossification After Using Recombinant Human Bone Morphogenetic Protein-2 in Transforaminal Lumbar Interbody Fusion: A Computed Tomography Review of 996 Disc Levels.

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: Reported incidences and complications of heterotopic ossification (HO) after using recombinant human bone morphogenetic protein-2 (rhBMP-2) in transforaminal lumbar interbody fusion (TLIF) have been inconclusive. This study was designed to evaluate both incidences of radiologic and symptomatic HO in a large series of TLIFs using rhBMP-2. METHODS: A total of 996 disc levels in 927 consecutive TLIF patients were retrospectively evaluated at 6-month postoperative follow-up in a single surgical practice. Subjects were separated into the BMP group and the control group. Operative reports, pre- and postoperative medical records were reviewed. Computed tomography (CT) scans were analyzed and graded independently for ossification at each disc level of TLIF. RESULTS: A total of 933 disc levels were in the BMP group, and 63 were in the control group. Six-month fusion rate of interbody was 92.5% in the BMP group, which was significantly higher in contrast to 71.4% in the control group (P < .001). The incidence of radiologic HO in the BMP group was 13.5%, which was significantly higher than 1.6% in the control group (P = .006). After controlling for basic demographics and comorbidities, the presence of radiologic HO was significantly associated with the use of rhBMP-2 (P = .026). However, only one case in the BMP group (0.11%) developed a symptomatic HO (mild-medium left buttock pain, treated nonsurgically) involving left foramen of L5-S1. CONCLUSIONS: rhBMP-2 can be safely used in TLIF with regard to HO. There was a low rate of radiologic HO and minimal symptomatic HO, with high fusion rates at 6 months postoperative.

The Frequency of Various "Myelopathic Symptoms" in Cervical Myelopathy: Evaluation in a Large Surgical Cohort.

STUDY DESIGN: A retrospective cohort of prospective data. OBJECTIVE: Determine the frequency of various symptoms in a surgical cohort of cervical myelopathy (CM). SUMMARY OF BACKGROUND DATA: CM can be difficult to diagnose as there is no sine qua non "myelopathic symptom." Despite extensive literature, the likelihood or frequency of symptoms at presentation remains unclear. MATERIALS AND METHODS: A total of 484 patients treated at a single academic center were reviewed. Preoperative symptoms included: axial neck pain; upper extremity (UE) pain; UE sensory or motor deficit; lower extremity (LE) sensory or motor deficit; and sphincter dysfunction. It was noted whether a symptom was the chief complaint (CC) and/or one of a list of overall symptoms (OS) reported by the patient. Magnetic resonance imaging was assessed for the maximal cord compression level and T2 hyperintensity. RESULTS: The most common CC was UE sensory deficit (46.5%), whereas the most common OS were UE and LE motor deficits (82.6% and 81.2%). Neck pain was significantly less common (32.6% CC, 55.4% OS), and sphincter dysfunction was rare (0.6% CC, 16.5% OS). UE pain as a CC was significantly higher when the maximal compression involved a more distal level. The presence of T2 hyperintensity was negatively associated with neck pain but positively associated with sensory and motor deficits of LE. CONCLUSIONS: The most common CC in CM related to UE sensation, whereas the most common OS related to upper and lower motor function. UE pain was more common with more distal cord compression. Those with T2 hyperintensity had worse myelopathy and were less likely to have neck pain, but more likely to have LE symptoms. To our knowledge, this study is the largest to quantify the frequency of myelopathic symptom presentation in a surgical population. These findings provide valuable insight into the symptomatic presentation of CM in clinical practice and can be used to better inform diagnosis and treatment in this complex patient population. LEVEL OF EVIDENCE: Level II-retrospective study.

Tc-99m-MAA lung shunt fraction before Y-90 radioembolization is low among patients with non-hepatocellular carcinoma malignancies.

OBJECTIVE: Lung shunt fraction studies using technetium-99 m macro aggregated albumin are routinely performed before yttrium-90 radioembolization regardless of underlying liver malignancy type. This study evaluates the role of lung shunt fraction studies in hepatocellular carcinoma compared to non-hepatocellular carcinoma liver tumors. METHODS: A single-institution retrospective analysis of all pre-yttrium-90 technetium-99 m macro aggregated albumin lung shunt fraction studies between November 2012 to March 2018 was performed. Patient variables including age, underlying malignancy, laboratory values, lung shunt fraction, and severity of liver disease were compared between hepatocellular carcinoma and non-hepatocellular carcinoma cases. RESULTS: A total of 734 technetium-99 m macro aggregated albumin studies were identified in 653 patients. Among these cases, the liver tumor was hepatocellular carcinoma in 368 (50.1%), colorectal cancer in 112 (15.3%), neuroendocrine tumor in 89 (12.1%), cholangiocarcinoma in 59 (8.0%), breast cancer in 27 (3.7%), and other metastatic malignancies in 79 (10.7%). The mean lung shunt fraction for non-hepatocellular carcinoma cases was 7.4%, which was significantly lower than the mean lung shunt fraction, 11.7%, for hepatocellular carcinoma cases (P = 0.0001). In only one non-hepatocellular carcinoma case was yttrium-90 radioembolization not pursued due to high lung shunt fraction (69.3%), wherein large scale shunting was grossly apparent on angiography in a patient with metastatic gastrointestinal stromal tumor. In comparison, the lung shunt fraction was too high to pursue radioembolization in 37 hepatocellular carcinoma cases (mean lung shunt fraction 35.1%). CONCLUSION: Lung shunt fraction appears low among patients with non-hepatocellular carcinoma liver malignancies. Further analysis examining the necessity of pre-Y90 technetium-99 m macro aggregated albumin lung shunt fraction studies in patients with non-hepatocellular carcinoma malignancies is warranted, since a consolidated yttrium-90 radioembolization without prior lung shunt fraction evaluation could reduce resource consumption, improve workflows, and patient access.