scholarly journals Real Time Electronic Feedback for Improved Acoustic Trapping of Micron-Scale Particles

Micromachines ◽  
2019 ◽  
Vol 10 (7) ◽  
pp. 489 ◽  
Author(s):  
Clark ◽  
Farmehini ◽  
Spiers ◽  
Woolf ◽  
Swami ◽  
...  

Acoustic differential extraction has been previously reported as a viable alternative to the repetitive manual pipetting and centrifugation steps for isolating sperm cells from female epithelial cells in sexual assault sample evidence. However, the efficiency of sperm cell isolation can be compromised in samples containing an extremely large number of epithelial cells. When highly concentrated samples are lysed, changes to the physicochemical nature of the medium surrounding the cells impacts the acoustic frequency needed for optimal trapping. Previous work has demonstrated successful, automated adjustment of acoustic frequency to account for changes in temperature and buffer properties in various samples. Here we show that, during acoustic trapping, real-time monitoring of voltage measurements across the piezoelectric transducer correlates with sample-dependent changes in the medium. This is achieved with a wideband peak detector circuit, which identifies the resonant frequency with minimal disruption to the applied voltage. We further demonstrate that immediate, corresponding adjustments to acoustic trapping frequency provides retention of sperm cells from high epithelial cell-containing mock sexual assault samples.

Author(s):  
V. F. Allison ◽  
G. C. Fink ◽  
G. W. Cearley

It is well known that epithelial hyperplasia (benign hypertrophy) is common in the aging prostate of dogs and man. In contrast, little evidence is available for abnormal epithelial cell growth in seminal vesicles of aging animals. Recently, enlarged seminal vesicles were reported in senescent mice, however, that enlargement resulted from increased storage of secretion in the lumen and occurred concomitant to epithelial hypoplasia in that species.The present study is concerned with electron microscopic observations of changes occurring in the pseudostratified epithelium of the seminal vescles of aging rats. Special attention is given to certain non-epithelial cells which have entered the epithelial layer.


Author(s):  
D.G. Osborne ◽  
L.J. McCormack ◽  
M.O. Magnusson ◽  
W.S. Kiser

During a project in which regenerative changes were studied in autotransplanted canine kidneys, intranuclear crystals were seen in a small number of tubular epithelial cells. These crystalline structures were seen in the control specimens and also in regenerating specimens; the main differences being in size and number of them. The control specimens showed a few tubular epithelial cell nuclei almost completely occupied by large crystals that were not membrane bound. Subsequent follow-up biopsies of the same kidneys contained similar intranuclear crystals but of a much smaller size. Some of these nuclei contained several small crystals. The small crystals occurred at one week following transplantation and were seen even four weeks following transplantation. As time passed, the small crystals appeared to fuse to form larger crystals.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Kazuki Motomura ◽  
Hidenori Takeuchi ◽  
Michitaka Notaguchi ◽  
Haruna Tsuchi ◽  
Atsushi Takeda ◽  
...  

AbstractDuring the double fertilization process, pollen tubes deliver two sperm cells to an ovule containing the female gametes. In the pollen tube, the vegetative nucleus and sperm cells move together to the apical region where the vegetative nucleus is thought to play a crucial role in controlling the direction and growth of the pollen tube. Here, we report the generation of pollen tubes in Arabidopsis thaliana whose vegetative nucleus and sperm cells are isolated and sealed by callose plugs in the basal region due to apical transport defects induced by mutations in the WPP domain-interacting tail-anchored proteins (WITs) and sperm cell-specific expression of a dominant mutant of the CALLOSE SYNTHASE 3 protein. Through pollen-tube guidance assays, we show that the physiologically anuclear mutant pollen tubes maintain the ability to grow and enter ovules. Our findings provide insight into the sperm cell delivery mechanism and illustrate the independence of the tip-localized vegetative nucleus from directional growth control of the pollen tube.


Author(s):  
Priyanto Hidayatullah ◽  
Xueting Wang ◽  
Toshihiko Yamasaki ◽  
Tati L.E.R. Mengko ◽  
Rinaldi Munir ◽  
...  

2020 ◽  
pp. 194589242098241
Author(s):  
Hai Lin ◽  
Guangyi Ba ◽  
Ru Tang ◽  
Mingxian Li ◽  
Zhipeng Li ◽  
...  

Background Oxidative stress plays crucial roles in the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP). Thioredoxin-interacting protein (TXNIP) is essential in the process of triggering oxidative stress. However, its role and mechanism in CRSwNP remain unclear. The present study sought to explore the role and mechanism of TXNIP in the pathogenesis of CRSwNP. Methods Western blotting, real-time PCR and immunohistochemistry (IHC) were employed to assess TXNIP, thioredoxin (TRX) expression in nasal tissue samples from patients with CRSwNP and control subjects. MDA level and SOD activity in nasal tissue homogenates were measured using MDA and SOD Assay Kit. To evaluate the role and mechanism of TXNIP in CRSwNP, human nasal epithelial cells (HNECs) were cultured and stimulated using TXNIP siRNA, with or without N-acetylcysteine (NAC, an ROS scavenger). Western blotting, real-time PCR, ROS detecting dye DCFH-DA, MDA and SOD Assay Kit were performed to assess the effects and mechanisms of stimulators on the cells. Results We found significantly increased levels of TXNIP and decreased levels of TRX protein, mRNA, positive cells, increased MDA level and decreased SOD activity in CRSwNP patients compared with control subjects. In vitro study, significantly altered levels of TXNIP, TRX, MDA, SOD and ROS in HNECs were found following treatment of TXNIP siRNA with or without NAC on HNECs. Conclusion TXNIP expression was increased and TRX expression was decreased in CRSwNP at both protein and mRNA levels. MDA levels were increased and SOD activities were decreased in CRSwNP. TXNIP may have negative association with TRX, and then decrease SOD activities and increase MDA levels, resulting in the upregulation of ROS and oxidative stress in HNECs, which may play a pivotal role in the pathogenesis of CRSwNP. Future studies are expected to further explore the role and mechanism of TXNIP in CRSwNP.


1993 ◽  
Vol 264 (1) ◽  
pp. F149-F157 ◽  
Author(s):  
J. Gailit ◽  
D. Colflesh ◽  
I. Rabiner ◽  
J. Simone ◽  
M. S. Goligorsky

Tubular obstruction by detached renal tubular epithelial cells is a major cause of oliguria in acute renal failure. Viable renal tubular cells can be recovered from urine of patients with acute tubular necrosis, suggesting a possible defect in cell adhesion to the basement membrane. To study this process of epithelial cell desquamation in vitro, we investigated the effect of nonlethal oxidative stress on the integrin adhesion receptors of the primate kidney epithelial cell line BS-C-1. Morphological and functional studies of cell adhesion properties included the following: interference reflection microscopy, intravital confocal microscopy and immunocytochemistry, flow cytometric analysis of integrin receptor abundance, and cell-matrix attachment assay. High levels of the integrin subunits alpha 3, alpha v, and beta 1 were detected on the cell surface by fluorescence-activated cell sorting (FACS) analysis, as well as lower levels of alpha 1, alpha 2, alpha 4, alpha 5, alpha 6, and beta 3. Exposure of BS-C-1 cells to nonlethal oxidative stress resulted in the disruption of focal contacts, disappearance of talin from the basal cell surface, and in the redistribution of integrin alpha 3-subunits from predominantly basal location to the apical cell surface. As measured in a quantitative cell attachment assay, oxidative stress decreased BS-C-1 cell adhesion to type IV collagen, laminin, fibronectin, and vitronectin. Defective adhesion was not associated with a loss of alpha 3-, alpha 4-, or alpha v-integrin subunits from the cell surface.(ABSTRACT TRUNCATED AT 250 WORDS)


2015 ◽  
Vol 226 (3) ◽  
pp. 135-143 ◽  
Author(s):  
Tatiana Dorfman ◽  
Yulia Pollak ◽  
Rima Sohotnik ◽  
Arnold G Coran ◽  
Jacob Bejar ◽  
...  

The Wnt/β-catenin signaling cascade is implicated in the control of stem cell activity, cell proliferation, and cell survival of the gastrointestinal epithelium. Recent evidence indicates that the Wnt/β-catenin pathway is activated under diabetic conditions. The purpose of this study was to evaluate the role of Wnt/β-catenin signaling during diabetes-induced enteropathy in a rat model. Male rats were divided into three groups: control rats received injections of vehicle; diabetic rats received injections of one dose of streptozotocin (STZ); and diabetic–insulin rats received injections of STZ and were treated with insulin given subcutaneously at a dose of 1 U/kg twice daily. Rats were killed on day 7. Wnt/β-catenin-related genes and expression of proteins was determined using real-time PCR, western blotting, and immunohistochemistry. Among 13 genes identified by real-time PCR, seven genes were upregulated in diabetic rats compared with control animals including the target genes c-Myc and Tcf4. Diabetic rats also showed a significant increase in β-catenin protein compared with control animals. Treatment of diabetic rats attenuated the stimulating effect of diabetes on intestinal cell proliferation and Wnt/β-catenin signaling. In conclusion, enhanced intestinal epithelial cell proliferation in diabetic rats correlates with β-catenin accumulation.


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