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Harvesting adherent cells from microcarriers has become one of the major challenges of the downstream bioprocessing at large scale the current method has high maintenance and operation cost, which are the results of frequent clogging, due to cell lysing effect and microcarrier cake formation on membrane-based technology. These problems hugely impede the adaptation of microcarriers technologies in large-scale cell culture and hampered the supply of cells to the clinical need. Here, we describe two 3D printing-based methods to fabricate inertial microfluidic devices for separating adherent cells from microcarriers which overcome the above-mentioned limitations. The spiral devices are employed to separate mesenchymal stem cells from the microcarriers with 99% microcarrier removal rate and 77% cell recovery rate in one round of separation., (© 2021. Springer Science+Business Media, LLC.)

Recently, particle concentration and filtration using inertial microfluidics have drawn attention as an alternative to membrane and centrifugal technologies for industrial applications, where the target particle size varies between 1 µm and 500 µm. Inevitably, the bigger particle size (>50 µm) mandates scaling up the channel cross-section or hydraulic diameter (D H > 0.5 mm). The Dean-coupled inertial focusing dynamics in spiral microchannels is studied broadly; however, the impacts of secondary flow on particle migration in a scaled-up spiral channel is not fully elucidated. The mechanism of particle focusing inside scaled-up rectangular and trapezoidal spiral channels (i.e., 5-10× bigger than conventional microchannels) with an aim to develop a continuous and clog-free microfiltration system for bioprocessing is studied in detail. Herein, a unique focusing based on inflection point without the aid of sheath flow is reported. This new focusing mechanism, observed in the scaled-up channels, out-performs the conventional focusing scenarios in the previously reported trapezoidal and rectangular channels. Finally, as a proof-of-concept, the utility of this device is showcased for the first time as a retention system for a cell-microcarrier (MC) suspension culture., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Rapidly evolving cell-based therapies towards clinical trials demand alternative approaches for efficient expansion of adherent cell types such as human mesenchymal stem cells (hMSCs). Using microcarriers (100-300 µm) in a stirred tank bioreactor offers considerably enhanced surface to volume ratio of culture environment. However, downstream purification of the harvested cell product needs to be addressed carefully due to distinctive features and fragility of these cell products. This work demonstrates a novel alternative approach which utilizes inertial focusing to separate microcarriers (MCs) from the final cell suspension. First, we systematically investigated MC focusing dynamics inside scaled-up curved channels with trapezoidal and rectangular cross-sections. A trapezoidal spiral channel with ultra-low-slope (Tan(α) = 0.0375) was found to contribute to strong MC focusing (~300 < Re < ~400) while managing high MC volume fractions up to ~1.68%. Accordingly, the high-throughput trapezoidal spiral channel successfully separated MCs from hMSC suspension with total cell yield~94% (after two passes) at a high volumetric flow rate of ~30 mL/min (Re~326.5).

Gastro-esophageal reflux currently is widespread disorders with dangerous complications. GLP-2 is a peptide that has trophic and anti-inflammatory effects on gastrointestinal mucosa. The aim of this study was to evaluate the protective role of GLP-2 in esophageal mucosa lesion due to perfusion acid-pepsin. Thirty-six male rats were used in this study and divided into six groups. They were control, acid-pepsin, GLP-2 20 μg, GLP-2 30 μg, GLP-2 40 μg and GLP-2 50 μg/kg groups. Esophageal blood flow, plasma NO metabolite, esophageal tissue NO metabolites and histological study of esophagus were performed as indicators of esophageal damage following acid-pepsin perfusion. Results showed that GLP-2 significantly increased plasma and tissue NO metabolites in comparison to acid-pepsin group. Also histological study showed significantly fewer lesions in the most effective dose GLP-2 30 μg in comparison to acid-pepsin group, our results show that GLP-2 could be useful for the treatment of esophageal in animal model., (Copyright © 2011. Published by Elsevier Inc.)

Pyrrolo[2,3-d]pyrimidine is known to have a broad spectrum of biological activities, including antitumor activity. The cytotoxic properties of six novel pyrrolo[2,3-d]pyrimidin-4-ones in vitro were investigated on four different human cancer cell lines. Meanwhile, the role of apoptosis was explored. Malignant cells were cultured in RPMI medium and incubated with different concentrations. Cell viability was quantitated by MTT assay. Apoptotic cells were determined using DAPI (4'-6-diamidino-2-phenylindole) and propidium iodide staining of DNA fragmentation by flow cytometry (sub-G1 peak). We have identified new analogs as a novel class of antiproliferative agents by a cell-based screening method. All compounds inhibited the growth of malignant cells in a dose-dependent manner. The IC₅₀ of compounds 4 and 5 as the two most potent analogs was determined as 122.4 and 106.7 μM in HeLa cells, respectively. Compounds 4 and 5 induced a sub-G1 peak in the flow-cytometry histogram of treated cells, compared to control, indicating that apoptotic cell death is involved in compound 4- and 5-induced toxicity. In conclusion, compounds 4 and 5 exert cytotoxic effects in different cancer cell lines in which apoptosis plays an important role. Thus, compounds 4 and 5 could be considered as potential chemotherapeutic agents.

Rosiglitazone (RGZ), a peroxisome proliferator-activated receptor-gamma (PPAR-gamma), has been shown to provide neuroprotective and anti-inflammatory effects in the acute phase of cerebral ischemia, and traumatic or surgical brain injuries. However, the effect of delayed post ischemia administration of this compound is still unclear. This study was designed to evaluate the neuroprotective effects of RGZ when first administered at 24 h after the embolic model of stroke. Embolic focal cerebral ischemia was induced in rats by placing a preformed clot into the middle cerebral artery (MCA). RGZ (5 mg/kg, intraperitoneally) was injected at 24 and 48 h after MCA embolization. Neurological deficits were evaluated at 24, 48 and 72 h after stroke, and blood and brain tissues were then collected for differential blood cell counts and assessments of infarct volume and DNA fragmentation, respectively. Compared to the control group, the administration of RGZ, starting 24 h after cerebral ischemia, reduced infarct volume by 56% (P<0.05) and decreased neurological deficits at 72 h after cerebral ischemia (P<0.05). Also, delayed administration of RGZ prevented neutrophilia in blood (P<0.005) and significantly decreased DNA fragmentation (P<0.05), 72 h after MCA occlusion. Therefore, our data demonstrate that treatment with RGZ, starting 24 h after stroke, can reduce ischemic injury, improve neurological outcome, and prevent neutrophilia. These findings may support the idea that RGZ has an extended therapeutic window for the treatment of ischemic stroke, as it targets delayed pathways.

Objective: The efficacy of erythromycin in treatment of knee effusion due to osteoarthritis was evaluated., Method: We assessed efficacy and safety of erythromycin during 16 weeks in patients enrolled in a randomized double-blind study. One hundred and eight patients with knee effusion due to osteoarthritis (OA) received 12-week courses of erythromycin or placebo allocated randomly, and were followed for 4 months. Acetaminophen 650 mg/day was used in both groups, while they received no other anti-inflammatory drugs (such as corticosteroid or nonsteroidal anti-inflammatory drugs) during the course of the study. Our patients were divided in two groups, erythromycin in doses of 200 mg four times per day was given to the first group (51 patients) over the first 3 months of the study and in the second group we used placebo with the same dosage and schedule (53 patients). Outcomes improvement for the erythromycin-treated group was assessed by a significantly higher mean score from baseline to the end of the trial, compared with placebo group. Patients were examined monthly during the treatment period. Measurement values included recording of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire subscales (pain, stiffness and function), range of motion and knee circumference., Results: Erythromycin produced a higher response rate than placebo in treatment of knee effusion due to OA. Significant reduction in knee circumference (P < 0.0005) and pain (P < 0.001) with functional improvement (P < 0.0005) were seen. At the first month after treatment, 11.8% (6 patients) in erythromycin and 9.4% (5 patients) in placebo groups had 50% pain reduction, which was not significant (P = 0.75). At the fourth month, 50% reduction of pain was seen in 45.1% (23 patients) of the erythromycin and 11.3% (6 patients) of the placebo group. This was statistically significant (P < 0.0005). Erythromycin treatment was well tolerated and mild adverse events caused no discontinuation during the study., Conclusion: This is a placebo-controlled study of macrolid efficacy on knee effusion due to OA in a short period. Results of this research showed the better efficacy of erythromycin in controlling effusion and pain with functional improvement in patients with knee effusion due to OA.

Previous studies involving exercise and memory showed that learning and memory were improved by exercise. This study was performed to find the effect of treadmill running on memory. Mid-term memory and swim speed were measured within 8 days. Twenty rats were divided into two groups, a control and a test group. Mid-term memory and swim speed were measured in the Morris water maze apparatus. Our results showed that treadmill running produced a significant enhancement on mid-term memory and swim speed in the test group, which may be mediated by specific molecular pathways.

Previous studies on exercise have shown that physical activity improves learning and memory. Present study was performed to determine the effects of acute, chronic and continuous exercise with different periods on spatial learning and memory recorded as the latency and length of swim path in the Morris water maze testing in subsequent 8 days. Four rat groups were included as follows: (1) group C, controls which did not exercise; (2) group A, 30 days treadmill running before and 8 days during the Morris water maze testing period; (3) group B, 30 days exercise before the Morris water maze testing period only; (4) group D, 8 days exercise only during the Morris water maze testing period. The results showed that chronic (30 days) and continuous (during 8 days of Morris water maze testing days) treadmill training produced a significant enhancement in spatial learning and memory which was indicated by decreases in path length and latency to reach the platform in the Morris water maze test (p<0.05). The benefits in these tests were lost in 3 days, if the daily running session was abandoned. In group D with acute treadmill running (8 days exercise only) the difference between the group A disappeared in 1 week and benefit seemed to be obtained in comparison with the controls without running program. In conclusion the chronic and daily running exercises promoted learning and memory in Morris water maze, but the benefits were lost in few days without daily running sessions in adult rats.