scholarly journals Bladder filling and voiding affect umbrella cell tight junction organization and function

2013 ◽  
Vol 305 (8) ◽  
pp. F1158-F1168 ◽  
Author(s):  
Marcelo D. Carattino ◽  
H. Sandeep Prakasam ◽  
Wily G. Ruiz ◽  
Dennis R. Clayton ◽  
Meredith McGuire ◽  
...  

Epithelial cells are continuously exposed to mechanical forces including shear stress and stretch, although the effect these forces have on tight junction (TJ) organization and function are poorly understood. Umbrella cells form the outermost layer of the stratified uroepithelium and undergo large cell shape and surface area changes during the bladder cycle. Here we investigated the effects of bladder filling and voiding on the umbrella cell TJ. We found that bladder filling promoted a significant increase in the length of the TJ ring, which was quickly reversed within 5 min of voiding. Interestingly, when isolated uroepithelial tissue was mounted in Ussing chambers and exposed to physiological stretch, we observed a 10-fold drop in both transepithelial electrical resistance (TER) and the umbrella cell junctional resistance. The effects of stretch on TER were reversible and dependent on the applied force. Furthermore, the integrity of the umbrella cell TJ was maintained in the stretched uroepithelium, as suggested by the limited permeability of biotin, fluorescein, and ruthenium red. Finally, we found that depletion of extracellular Ca2+ by EGTA completely disrupted the TER of unstretched, but not of stretched uroepithelium. Taken together, our studies indicate that the umbrella cell TJ undergoes major structural and functional reorganization during the bladder cycle. The impact of these changes on bladder function is discussed.

2019 ◽  
Vol 20 (17) ◽  
pp. 4070 ◽  
Author(s):  
Matthew G. Brewer ◽  
Takeshi Yoshida ◽  
Fiona I. Kuo ◽  
Sade Fridy ◽  
Lisa A. Beck ◽  
...  

Atopic dermatitis (AD) is the most common chronic and relapsing inflammatory skin disease. AD is typically characterized by skewed T helper (Th) 2 inflammation, yet other inflammatory profiles (Th1, Th17, Th22) have been observed in human patients. How cytokines from these different Th subsets impact barrier function in this disease is not well understood. As such, we investigated the impact of the canonical Th17 cytokine, IL-17A, on barrier function and protein composition in primary human keratinocytes and human skin explants. These studies demonstrated that IL-17A enhanced tight junction formation and function in both systems, with a dependence on STAT3 signaling. Importantly, the Th2 cytokine, IL-4 inhibited the barrier-enhancing effect of IL-17A treatment. These observations propose that IL-17A helps to restore skin barrier function, but this action is antagonized by Th2 cytokines. This suggests that restoration of IL-17/IL-4 ratio in the skin of AD patients may improve barrier function and in so doing improve disease severity.


1999 ◽  
Vol 276 (6) ◽  
pp. G1322-G1330 ◽  
Author(s):  
Nelia A. Tobey ◽  
Dipali Sikka ◽  
Esteban Marten ◽  
Canan Caymaz-Bor ◽  
S. Seraj Hosseini ◽  
...  

Hot beverages expose the esophageal epithelium to temperatures as high as 58°C. To study the impact of such temperatures, rabbit esophageal epithelium was exposed to luminal heat or both luminal and serosal heat while mounted in Ussing chambers. Luminal heat, mimicking exposure to hot beverages, reduced potential difference (PD) and resistance ( R) when applied at ≥49°C and reduced short-circuit current ( I sc) at ≥60°C. At ≥60°C, subepithelial blisters developed. Higher temperatures reduced R only moderately and reversibly. In contrast, the I sc declined sharply and irreversibly once threshold was reached. Luminal and serosal heat also reduced PD, I sc, and R, although the threshold for reduction in I scwas now similar to that for R. Additionally, luminal and serosal heat reduced I sc more than R for any given temperature and resulted in blisters at lower temperatures (50°C) than luminal heat alone. The heat-induced decline in I sc was attributed in part to inactivation of Na-K-ATPase activity, although other transport systems could have been equally affected, and the decline in R to an increase in paracellular permeability. The latter effect on R also contributed to an increase in tissue sensitivity to luminal acid damage. Consumption of hot beverages exposes the esophagus to temperatures that can negatively impact epithelial structure and function. Impaired barrier function by heat increases the risk of esophageal damage by subsequent contact with (refluxed) gastric acid. These findings help explain in part the association between esophageal disease and consumption of hot beverages.


2019 ◽  
Vol 97 (Supplement_2) ◽  
pp. 190-190
Author(s):  
Carson De Mille ◽  
Emma T Helm ◽  
Crystal L Loving ◽  
Eric R Burrough ◽  
Nicholas K Gabler

Abstract The objective of this study was to evaluate the impact of sub-therapeutic chlortetracycline (CTC) and pharmacological zinc oxide on nursery pig performance and intestinal integrity and function. Twenty-four newly weaned pigs (4.51 ± 0.21 kg BW) were randomly assigned to one of three dietary treatments for 21 d (n = 8/treatment): 1) Control diet (NC), 2) NC + Zinc oxide at 3000 ppm for 7 d followed by 2000 ppm for 14 d (ZnO), and 3) NC + 40 ppm CTC for 21 d (sCTC). Pig ADG, ADFI, and G:F were determined for the overall 21 d test period. At d 21, all pigs were euthanized for tissue collection. Jejunum and ileum ex vivo transepithelial resistance (TER), macromolecule (FD4) flux, and active glucose and glutamine transport were assessed in modified Ussing Chambers. Additionally, jejunum brush border enzyme and Na+/K+ ATPase activities were determined. Morphology and T-cell abundance were determined in all ileum sections by H&E staining and immunohistochemistry, respectively. Compared to the NC, sCTC and ZnO increased ADG (0.14, 0.20 and 0.23 kg/d, respectively, P = 0.020). Overall ADFI was increased by 150% due to sCTC compared to the NC and ZnO pigs (P < 0.05). G:F was increased due to ZnO and sCTC compared to the NC (0.82, 0.63 and 0.47, respectively, P < 0.01). Jejunum and ileum ex vivo function and integrity did not differ. Ileal villus height was increased in the NC compared to sCTC treatment (P < 0.01), but not different from the ZnO treatment. In the ileum, total T-cell number per unit area was significantly lower in the ZnO segments compared to sCTC and NC (0.95, 2.29 and 2.59 count per μm2, respectively, P = 0.05). These data indicate that ZnO and sCTC improved pig performance but did not directly alter small intestinal integrity and function. However, mucosal T cell abundance was altered.


2019 ◽  
Vol 97 (Supplement_2) ◽  
pp. 148-149
Author(s):  
Samuel Gerrard ◽  
Emma T Helm ◽  
Blaire Todd ◽  
Nicholas K Gabler

Abstract Porcine reproductive and respiratory syndrome (PRRS) virus infections and mycotoxin contaminated feedstuffs are two common issues facing the pork industry as both act, independently, to antagonize pig intestinal function, growth performance, and health. However, the combined impact of PRRS and mycotoxin exposure on pig intestinal health and function has not been investigated. Therefore, the objective of this experiment was to examine the impact of the mycotoxin deoxynivalenol (DON) on the intestinal integrity and function of PRRS infected pigs, employing an ex vivo model. Jejunum samples were collected from PRRS naïve (control; n = 6) and 21 day post inoculated PRRS virus infected (n = 8) gilts (10 weeks of age). In duplicate, explants were mounted into modified Ussing Chambers and incubated with or without 25 mM DON for 45 minutes prior to assessment of transepithelial resistance (TER), mucosal to serosal macromolecule (FD4) flux, and active glucose and glutamine transport. Data were analyzed using the mixed model procedure of SAS and a split plot design to examine the fixed effects of PRRS, DON, and their interaction. There were no PRRS by DON interactions for any ex vivo parameters assessed. Irrespective of DON, PRRS jejunum segments had decreased TERs (57%, P < 0.001), increased FD4 flux (P = 0.005), and tended to have increased active glucose transport (P = 0.093) compared with uninfected controls. Irrespective of PRRS status, DON increased FD4 flux (113%, P = 0.013), and tended to increase active glucose transport (P = 0.088) compared with jejunal explants not treated with DON. However, TERs and active glutamine transport did not differ due to DON treatment. Taken together, these data highlight the impacts that viral health challenge and mycotoxin contamination have on aspects of intestinal integrity and function. However, it does not appear that PRRS challenged pigs are more sensitive to the effects of DON than their healthy counterparts.


2016 ◽  
Vol 1 (13) ◽  
pp. 162-168
Author(s):  
Pippa Hales ◽  
Corinne Mossey-Gaston

Lung cancer is one of the most commonly diagnosed cancers across Northern America and Europe. Treatment options offered are dependent on the type of cancer, the location of the tumor, the staging, and the overall health of the person. When surgery for lung cancer is offered, difficulty swallowing is a potential complication that can have several influencing factors. Surgical interaction with the recurrent laryngeal nerve (RLN) can lead to unilateral vocal cord palsy, altering swallow function and safety. Understanding whether the RLN has been preserved, damaged, or sacrificed is integral to understanding the effect on the swallow and the subsequent treatment options available. There is also the risk of post-surgical reduction of physiological reserve, which can reduce the strength and function of the swallow in addition to any surgery specific complications. As lung cancer has a limited prognosis, the clinician must also factor in the palliative phase, as this can further increase the burden of an already compromised swallow. By understanding the surgery and the implications this may have for the swallow, there is the potential to reduce the impact of post-surgical complications and so improve quality of life (QOL) for people with lung cancer.


2011 ◽  
Vol 21 (3) ◽  
pp. 112-117 ◽  
Author(s):  
Elizabeth Erickson-Levendoski ◽  
Mahalakshmi Sivasankar

The epithelium plays a critical role in the maintenance of laryngeal health. This is evident in that laryngeal disease may result when the integrity of the epithelium is compromised by insults such as laryngopharyngeal reflux. In this article, we will review the structure and function of the laryngeal epithelium and summarize the impact of laryngopharyngeal reflux on the epithelium. Research investigating the ramifications of reflux on the epithelium has improved our understanding of laryngeal disease associated with laryngopharyngeal reflux. It further highlights the need for continued research on the laryngeal epithelium in health and disease.


1998 ◽  
Vol 21 (1) ◽  
pp. 1-28
Author(s):  
John A Atkinson ◽  
Camilla Dickson ◽  
Jane Downes ◽  
Paul Robins ◽  
David Sanderson

Summary Two small burnt mounds were excavated as part of the programme to mitigate the impact of motorway construction in the Crawford area. The excavations followed a research strategy designed to address questions of date and function. This paper surveys the various competing theories about burnt mounds and how the archaeological evidence was evaluated against those theories. Both sites produced radiocarbon dates from the Bronze Age and evidence to suggest that they were cooking places. In addition, a short account is presented of two further burnt mounds discovered during the construction of the motorway in Annandale.


2020 ◽  
Vol 56 (2) ◽  
pp. 119-122
Author(s):  
Doris Adams Hill ◽  
Theoni Mantzoros ◽  
Jonté C. Taylor

Special educators are often considered the experts in their school when it comes to developing functional behavior assessments (FBA) and behavior intervention plans (BIP), yet rarely are they trained much beyond basic antecedents, behaviors, and consequences (ABC). This column discusses concepts that will expand special education professionals’ knowledge to make better decisions regarding interventions for the students they serve. Specifically, the focus is on motivating operations (MO) and function-based interventions and the implications of these on behavior. Knowledge of the concept of MOs can enhance a teacher’s ability to provide evidence-based interventions and more fully developed behavioral interventions for students in their purview.


Horticulturae ◽  
2020 ◽  
Vol 6 (4) ◽  
pp. 82
Author(s):  
Amandeep Kaur ◽  
Louise Ferguson ◽  
Niels Maness ◽  
Becky Carroll ◽  
William Reid ◽  
...  

Pecan is native to the United States. The US is the world’s largest pecan producer with an average yearly production of 250 to 300 million pounds; 80 percent of the world’s supply. Georgia, New Mexico, Texas, Arizona, Oklahoma, California, Louisiana, and Florida are the major US pecan producing states. Pecan trees frequently suffer from spring freeze at bud break and bloom as the buds are quite sensitive to freeze damage. This leads to poor flower and nut production. This review focuses on the impact of spring freeze during bud differentiation and flower development. Spring freeze kills the primary terminal buds, the pecan tree has a second chance for growth and flowering through secondary buds. Unfortunately, secondary buds have less bloom potential than primary buds and nut yield is reduced. Spring freeze damage depends on severity of the freeze, bud growth stage, cultivar type and tree age, tree height and tree vigor. This review discusses the impact of temperature on structure and function of male and female reproductive organs. It also summarizes carbohydrate relations as another factor that may play an important role in spring growth and transition of primary and secondary buds to flowers.


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