Activation of epithelial Na channels during short-term Na deprivation

2001 ◽  
Vol 280 (1) ◽  
pp. F112-F118 ◽  
Author(s):  
Gustavo Frindt ◽  
Shyama Masilamani ◽  
Mark A. Knepper ◽  
Lawrence G. Palmer
Keyword(s):  
Control Group ◽  
Na Channel ◽  
Na Channels ◽  
Charge Balance ◽  
Short Term ◽  
Patch Clamp Technique ◽  
Epithelial Na Channels ◽  
Group 5 ◽  
Collecting Tubules

The role of epithelial Na channels in the response of the kidney to short-term Na deprivation was studied in rats. Animals were fed either a control-Na (3.9 g/kg) or a low-Na ( 3.8 mg/kg) diet for 15 h. Urinary excretion of Na (μmol/min), measured in conscious animals in metabolic cages, was 0.45 ± 0.07 in controls and 0.04 ± 0.01 in Na-deprived animals. Glomerular filtration rate, measured as the clearance of creatinine, was unaffected by the change in diet, suggesting that the reduced Na excretion was the result of increased Na reabsorption. K excretion (μmol/min), increased after the 15-h period of Na deprivation from 0.70 ± 0.10 to 1.86 ± 0.19. Thus the decrease in urine Na was compensated for, in terms of electrical charge balance, by an increase in urine K. Plasma aldosterone increased from 0.50 ± 0.08 to 1.22 ± 0.22 nM. Principal cells from cortical collecting tubules isolated from the animals were studied by using the patch-clamp technique. Whole cell amiloride-sensitive currents were negligible in the control group (5 ± 4 pA/cell) but substantial in the Na-deprived group (140 ± 28 pA/cell). The abundance of the epithelial Na channel subunits, α, β, and γ in the kidney was estimated by using immunoblots. There was no change in the overall abundance of any of the subunits after the 15-h Na deprivation. However, the apparent molecular mass of a fraction of the γ-subunits decreased as was previously reported for long-term Na deprivation. Calculations of the rate of Na transport mediated by the Na channels indicated that activation of the channels during short-term Na deprivation could account in large part for the increased Na reabsorption under these conditions.

scholarly journals Efficacy of a bystander intervention for preventing dating violence in Brazilian adolescents: short-term evaluation

2019 ◽  
Vol 32 (1) ◽  
Author(s):  
Karine Brito dos Santos ◽  
Sheila Giardini Murta ◽  
Luis Gustavo do Amaral Vinha ◽  
Juliana Silva de Deus
Keyword(s):  
Romantic Relationships ◽  
Dating Violence ◽  
Control Group ◽  
Short Term ◽  
Brazilian Sample ◽  
Post Test ◽  
Short Term Evaluation ◽  
Term Evaluation ◽  
Brazilian Culture

Abstract Peers are the preferred source of help for Brazilian adolescents who experience dating violence. However, they are not always the best informants for effective responses for dealing with situations of violence in romantic relationships among peers. This experimental study aimed to evaluate the short-term efficacy of three aspects of a peer- and bystander approach-based intervention: the intent to offer help, empathy, and bystander attitudes in response to dating violence in a Brazilian sample of adolescents. The study’s participants were 33 adolescents randomized in two groups: experimental group (EG, n = 14) and control group (CG, n = 19). The EG underwent three weekly intervention sessions of 90 min each on the healthy versus violent romantic relationships, the quality of friendship in the peer network, and the role of the bystander, while the CG received no intervention. Evaluations were performed 1 week before and two and half months after the intervention. Statistically significant differences between EG and CG at post-test were not found in intention to help, empathy, and bystander attitudes. Future studies should include evaluations of larger samples and mid- and long-term follow-ups to identify patterns of change over the long term as well as examine barriers to utilization of bystander behaviors by adolescents in Brazilian culture.

scholarly journals Evaluation of the Policy Effect of China’s Environmental Interview System for Effective Air Quality Governance

2021 ◽  
Vol 18 (17) ◽  
pp. 9006
Author(s):  
Xue Jin ◽  
Ussif Rashid Sumaila ◽  
Kedong Yin ◽  
Zhichao Qi
Keyword(s):  
Air Quality ◽  
Environmental Protection ◽  
Environmental Sustainability ◽  
Local Governments ◽  
Local Governance ◽  
Assessment System ◽  
Control Group ◽  
Short Term ◽  
Interview System

The Ministry of Ecology and Environment of the People’s Republic of China formally proposed an environmental interview system in May 2014, which applies pressure on local governments to fulfill their responsibility toward environmental protection by conducting face-to-face public interviews with their officials. In this paper, 48 cities that were publicly interviewed from 2014–2020 were considered the experimental group and 48 cities surrounding them were the control group. First, the dynamic panel model is applied to initially determine the effect of the policy. Then, a regression discontinuity method (Sharp RD) is used to analyze the short-term and long-term effects and compare the reasons for the differences observed among the estimates of various types of samples. Finally, a series of robustness tests were also conducted. The results show that the environmental interview system can improve air quality. However, because an emergency short-term local governance system exists at present, the governance effect is not long-term and, therefore, not sustainable. Therefore, it suggests that the government should continue to improve the environmental interview system, establish an optimal environmental protection incentive mechanism, and encourage local governments to implement environmental protection policies effectively in the long term. The results of the research are of great significance to the environmental impact assessment system of the world, especially in countries with similar economic systems, which are facing a trade-off between economic growth and environmental sustainability.

Low Mortality of Larval Lampreys from Electrofishing, Suction-pumping, Anesthesia, and Handling

2017 ◽  
Vol 8 (2) ◽  
pp. 640-647 ◽  
Author(s):  
Jeffrey C. Jolley ◽  
Christina T. Uh ◽  
Gregory S. Silver ◽  
Timothy A. Whitesel
Keyword(s):  
Pacific Northwest ◽  
Control Group ◽  
Long Term Effects ◽  
Negative Effects ◽  
Short Term ◽  
Important Species ◽  
Pacific Lamprey ◽  
The Pacific ◽  
Delayed Mortality

Abstract Native lamprey populations are declining worldwide. In the Pacific Northwest focus on conservation and management of these ecologically and culturally important species has increased. Concern has emerged regarding the effects of sampling and handling of lamprey, with little to no attention given to the larval lifestage. We monitored the survival of larval Pacific Lamprey Entosphenus tridentatus and Lampetra spp. after backpack electrofishing, deepwater electrofishing and suction-pumping, anesthesia, and handling. We performed survival trials on wild-caught lamprey (n = 15 larvae in each trial) collected from the Clackamas River drainage in Oregon, USA, coupled with control group trials from lamprey sourced from a hatchery (n = 10 larvae). Short-term (96 h) survival was >98% with only one observed mortality. Delayed mortality (1 wk) was observed for four individuals that had fungus; two of those were positive for the bacteria Aeromonas hyrdrophila. We recorded blood hematocrit as a secondary measure of stress. The baseline, nonstressed larvae hematocrit levels did not differ from those of fish that had undergone stress through electrofishing, suction-pumping, and handling without anesthesia. Electrofishing, suction-pumping, and anesthesia showed no short-term negative effects on larval lamprey although potential long-term effects remain unstudied. These techniques appear to provide efficient and relatively safe methods for collecting and surveying larval lamprey.

Insulin resistance caused by amylin in conscious rats is independent of induced hypocalcemia and fades during long-term exposure

1993 ◽  
Vol 129 (4) ◽  
pp. 360-365 ◽  
Author(s):  
Clemens Fürnsinn ◽  
Peter Nowotny ◽  
Michael Roden ◽  
Madeleine Rohac ◽  
Thomas Pieber ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Insulin Sensitivity ◽  
Glucose Tolerance ◽  
Glucose Intolerance ◽  
Tolerance Test ◽  
Zucker Rats ◽  
Control Group ◽  
Short Term ◽  
Euglycemic Hyperinsulinemic Clamp

To compare the effect of short- vs long-term amylin infusion on insulin sensitivity, glucose tolerance and serum calcemia, euglycemic-hyperinsulinemic clamp (26 pmol·kg−1·min−1) and glucose tolerance tests (2.4 mmol/kg over 30 min) were performed in lean Zucker rats. Three infusion protocols were employed: control group: 24 h of iv saline; short-term amylin exposure: 22 h of iv saline followed by 2 h of iv amylin (20 μg/h); long-term amylin exposure: 24 h of iv amylin (20 μg/h). Insulin resistance was induced by short-term amylin infusion during euglycemic clamping, as shown by a 41% decrease in space-corrected glucose infusion rates (μmol·kg−1·min−1; control group, 106.0±15.0; short-term iv amylin, 62.7±15.0; p<0.00 5). After long-term amylin exposure, insulin sensitivity was identical to control values (109.9±6.7). This fading action of amylin was confirmed by data from the glucose tolerance test, demonstrating glucose intolerance after short- but not after long-term amylin exposure. Serum calcium concentration decreased during short-term (2 h) amylin infusion (from 2.52±0.15 to 2.09±0.12 mmol/l; p<0.01) and hypocalcemia of a similar extent also was present after 22 h and 24 h of amylin exposure (2.10±0.09 and 2.04±0.14 mmol/l, respectively). The data demonstrate that short-term amylin infusion induces insulin resistance and glucose intolerance, both of which vanish during long-term (>22 h) amylin exposure, being apparently independent of induced hypocalcemia.

Short-term effect of aldosterone on NEM-sensitive ATPase in rat collecting tubule

1989 ◽  
Vol 257 (2) ◽  
pp. F177-F181 ◽  
Author(s):  
C. Khadouri ◽  
S. Marsy ◽  
C. Barlet-Bas ◽  
A. Doucet
Keyword(s):  
Atpase Activity ◽  
Affinity Constant ◽  
Short Term ◽  
Collecting Tubule ◽  
Lag Period ◽  
In Vitro Effects ◽  
Collecting Tubules

Because previous studies indicated that in the collecting tubule, N-ethylmaleimide (NEM)-sensitive ATPase, the biochemical equivalent of the proton pump, is controlled by mineralocorticoids in the long term, the present study was designed to investigate whether such control also exists in the short term. Therefore we investigated the in vivo and in vitro effects of aldosterone on the enzyme activity in cortical and outer medullary collecting tubules (CCT and MCT, respectively) from adrenalectomized rats. Administration of aldosterone (10 micrograms/kg body wt) markedly stimulated NEM-sensitive ATPase activity in the CCT and MCT within 3 h. Similarly, incubating CCT or MCT for 3 h in the presence of 10(-8) M aldosterone enhanced NEM-sensitive ATPase activity up to values similar to those previously measured in the corresponding nephron segments of normal rats. In vitro stimulation of NEM-sensitive ATPase was dose dependent in regard to aldosterone (apparent affinity constant approximately 10(-9) M), appeared after a 30-min lag period, and reached its maximum after 2-2.5 h. Finally, actinomycin D and cycloheximide totally abolished the in vitro action of aldosterone, demonstrating the involvement of protein synthesis in this process.

Epithelial Na channels and short-term renal response to salt deprivation

2002 ◽  
Vol 283 (4) ◽  
pp. F717-F726 ◽  
Author(s):  
Gustavo Frindt ◽  
Tiffany McNair ◽  
Anke Dahlmann ◽  
Emily Jacobs-Palmer ◽  
Lawrence G. Palmer
Keyword(s):  
Distal Tubule ◽  
Treated Group ◽  
Na Channel ◽  
Na Channels ◽  
Nacl Transport ◽  
Drug Concentrations ◽  
Epithelial Na Channels ◽  
Late Evening ◽  
Excretion Rates

To test the role of epithelial Na channels in the day-to-day regulation of renal Na excretion, rats were infused via osmotic minipumps with the Na channel blocker amiloride at rates that achieved drug concentrations of 2–5 μM in the lumen of the distal nephron. Daily Na excretion rates were unchanged, although amiloride-treated animals tended to excrete more Na in the afternoon and less in the late evening than controls. When the rats were given a low-Na diet, Na excretion rates were elevated in the amiloride-treated group within 4 h and remained higher than controls for at least 48 h. Adrenalectomized animals responded similarly to the low-Na diet. In contrast, rats infused with polythiazide at rates designed to inhibit NaCl transport in the distal tubule were able to conserve Na as well as did the controls. Injection of aldosterone (2 μg/100 g body wt) decreased Na excretion in control animals after a 1-h delay. This effect was largely abolished in amiloride-treated rats. On the basis of quantitative analysis of the results, we conclude that activation of amiloride-sensitive channels by mineralocorticoids accounts for 50–80% of the immediate natriuretic response of the kidney to a reduction in Na intake. Furthermore, the channels are necessary to achieve minimal rates of Na excretion during more chronic Na deprivation.

Short-Term Postnatal Renal Function in Twin Anemia-Polycythemia Sequence

2015 ◽  
Vol 39 (3) ◽  
pp. 192-197 ◽  
Author(s):  
Lianne Verbeek ◽  
Femke Slaghekke ◽  
Romain Favre ◽  
Marine Vieujoz ◽  
Francesco Cavigioli ◽  
...  
Keyword(s):  
Renal Function ◽  
Renal Dysfunction ◽  
Gestational Age ◽  
Twin Pair ◽  
Control Group ◽  
Short Term ◽  
Monochorionic Twins ◽  
Gestational Age At Birth ◽  
Age At Birth

Objective: To evaluate the short-term renal function in neonates with twin anemia-polycythemia sequence (TAPS). Methods: All consecutive monochorionic twins with TAPS with double survivors admitted to three European centers were included in this retrospective study. Each twin pair was matched for gestational age at birth with a control twin pair unaffected by TAPS or twin-twin transfusion syndrome. Creatinine and urea levels in the first week after birth were recorded. Short-term postnatal renal dysfunction was defined as creatinine >100 μmol/l during the first week after birth. Results: A total of 52 TAPS twin pairs and 52 control twin pairs with a median gestational age of 31 weeks at birth were included in the study. In the TAPS group, donors had higher mean creatinine levels compared to recipients, 85 versus 71 μmol/l, respectively (p = 0.001). Short-term renal dysfunction was detected in 26.0% (13/50) of the donors versus 6.3% (3/48) of the recipients (p = 0.022). In the control group, no inter-twin differences in creatinine levels were found. Conclusions: Donor twins with TAPS have higher creatinine levels than recipient twins, suggesting that chronic inter-twin transfusion in TAPS may also cause short-term renal dysfunction. Long-term renal consequences in TAPS donors require further investigation.

scholarly journals Reconstitution of the complete rupture in musculotendinous junction using skeletal muscle-derived multipotent stem cell sheet-pellets as a “bio-bond”

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2231 ◽  
Author(s):  
Hiroyuki Hashimoto ◽  
Tetsuro Tamaki ◽  
Maki Hirata ◽  
Yoshiyasu Uchiyama ◽  
Masato Sato ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Stem Cell ◽  
Muscle Mass ◽  
Control Group ◽  
Short Term ◽  
Musculotendinous Junction ◽  
Multipotent Stem Cell ◽  
Recovery Group ◽  
Tetanic Tension

Background.Significant and/or complete rupture in the musculotendinous junction (MTJ) is a challenging lesion to treat because of the lack of reliable suture methods. Skeletal muscle-derived multipotent stem cell (Sk-MSC) sheet-pellets, which are able to reconstitute peripheral nerve and muscular/vascular tissues with robust connective tissue networks, have been applied as a “bio-bond”.Methods.Sk-MSC sheet-pellets, derived from GFP transgenic-mice after 7 days of expansion culture, were detached with EDTA to maintain cell–cell connections. A completely ruptured MTJ model was prepared in the right tibialis anterior (TA) of the recipient mice, and was covered with sheet-pellets. The left side was preserved as a contralateral control. The control group received the same amount of the cell-free medium. The sheet-pellet transplantation (SP) group was further divided into two groups; as the short term (4–8 weeks) and long term (14–18 weeks) recovery group. At each time point after transplantation, tetanic tension output was measured through the electrical stimulation of the sciatic nerve. The behavior of engrafted GFP+tissues and cells was analyzed by fluorescence immunohistochemistry.Results.The SP short term recovery group showed average 64% recovery of muscle mass, and 36% recovery of tetanic tension output relative to the contralateral side. Then, the SP long term recovery group showed increased recovery of average muscle mass (77%) and tetanic tension output (49%). However, the control group showed no recovery of continuity between muscle and tendon, and demonstrated increased muscle atrophy, with coalescence to the tibia during 4–8 weeks after operation. Histological evidence also supported the above functional recovery of SP group. Engrafted Sk-MSCs primarily formed the connective tissues and muscle fibers, including nerve-vascular networks, and bridged the ruptured tendon–muscle fiber units, with differentiation into skeletal muscle cells, Schwann cells, vascular smooth muscle, and endothelial cells.Discussion.This bridging capacity between tendon and muscle fibers of the Sk-MSC sheet-pellet, as a “bio-bond,” represents a possible treatment for various MTJ ruptures following surgery.

scholarly journals PERBANDINGAN ANTARA PEMBERIAN ANTIBIOTIKA PROFILAKSIS PADA SEKSIO SESAR SESUAI ALUR KLINIS RSUP DR SARDJITO DENGAN ANTIBIOTIKA DOSIS MULTIPEL TERHADAP KEJADIAN INFEKSI LUKA OPERASI

2016 ◽  
Vol 3 (2) ◽  
pp. 75
Author(s):  
Ardian Rahmansyah ◽  
Mohammad Hakimi ◽  
Rukmono Siswishanto
Keyword(s):  
Length Of Stay ◽  
Cesarean Section ◽  
Surgical Site Infection ◽  
Clinical Pathway ◽  
Intervention Group ◽  
Group Versus ◽  
Control Group ◽  
Site Infection ◽  
Short Term

Background: Clinical pathway recommend the use of short-term prophylaxis antibiotics for cesarean section. Long-term antibiotics or multiple doses was found in clinical practice. There are differences in the mode of administration and the number of doses administered at sardjito hospital.Objective: To determine the effectiveness of short-term antibiotic prophylaxis in cesarean section appropriate to clinical pathway in the prevention of surgical site infection (ssi), the incidence of fever, dysuria events, length of stay.Method: The study used randomized clinical trial. The study subjects who underwent cesarean section and meet the inclusion and exclusion criteria in the period July 2013 to January 2014 divided into an intervention group (n = 52) who received ampicillin 2 gram pre and post-cesarean section, and a control group (n = 54) who received ampicillin 2 gram pre cesarean section and 1 gram every 8 hours for 6 times. Observed on days 3 and 10 post-cesarean section. The primary outcomes assessed were the incidence of surgical wound infection based on the criteria of surgical site infection from Centers for Disease Controland Prevention. Secondary outcomes assessed were the incidence of fever, dysuria events, length of stay. Homogeneity analysis were conducted on subject. Outcome analysis performed bivariate with t test and chi squared test.Results and Discussion : A total of 106 subjects can be analyzed. SSI events in the intervention group at day 3 was 3.8% (n = 52) and control group was 1.84% (n = 54) with p>0.05 RR 2.077 (95% CI 0.194 to 22.219). SSI on day 10 of 7.7% (n = 52) in the intervention group versus 9.3% (n = 54) in controls with p<0.05 RR 0.831 (CI 95%, 0.236 to 2.924). Fever events on day 3 by 5.8% in the intervention group versus 3.7% incontrols with p>0.05 RR 1.558 (95% CI 0.271 to 8.948) and on day 10 was 3.8% versus 3.7 % with p>0.05 RR 1.038 (95% CI 0.152 to 7.102). Dysuria not found on day 3 and but on 10 found 5.8% in the intervention group versus 11.1% with p>0.05 RR 0.519 (IK95% 0.137 to 1.968). Length of stay after cesarean section for 3.21 ± 0.412 days in the intervention group and 3.26 ± 0.442 days in the control group with p>0.05 (95% CI -0.213 - 0.117).Conclusion: There is no significant difference in the incidence of surgical wound infections, the incidence of fever, dysuria, length of stay between short-term prophylaxis antibiotics ampicillin appropriate to clinical pathway and long-term or multiple doses prophylaxis antibiotics. Short term antibiotics prophylaxis are more efficiently with the same effectiveness in preventing outcomes research.Keywords: prophylaxis antibiotics, ampicillin, short term regimen, long term regimen, cesarean section, surgical site infection. 

scholarly journals Neoadjuvant Chemotherapy plus Bevacizumab Combined with Total Mesorectal Excision in Treating Locally Advanced Rectal Cancer Patients with BRAF Mutation: Clinical Benefit and Safety

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Jintian Song ◽  
Yi Wang ◽  
Hui Yu ◽  
Liang Zheng ◽  
Xiongchao Cai ◽  
...  
Keyword(s):  
Rectal Cancer ◽  
Clinical Benefit ◽  
Locally Advanced ◽  
Advanced Rectal Cancer ◽  
Locally Advanced Rectal Cancer ◽  
Control Group ◽  
Observation Group ◽  
Mesorectal Excision ◽  
Short Term

Objective. To investigate clinical benefit and safety of neoadjuvant chemotherapy (NAC) plus bevacizumab combined with total mesorectal excision (TME) in treating patients with BRAF-mutated locally advanced rectal cancer (LARC). Methods. This study included LARC patients with BRAF mutation admitted to the Oncology Department of Fujian Medical University Cancer Hospital, Fujian Cancer Hospital, between June 2013 and December 2018. Patients in the control group received a standard treatment regimen of TME combined with NAC ( n = 45 ), and patients in the observation group received NAC plus bevacizumab combined with TME ( n = 55 ). The short-term clinical efficacy of the two groups after NAC treatment was observed and compared, including differences in the pathological downstaging rate. The incidence of perioperative complications and adverse reactions during neoadjuvant therapy was compared to evaluate the safety of the treatment. Besides, the relapse-free survival (RFS) and overall survival (OS) of patients were analyzed to evaluate the long-term clinical benefit of the treatment. Results. Compared with the control group, the ypT staging rate ( p = 0.014 ) in the observation group was markedly lower. In addition, patients in the observation group had a prominently lower overall incidence of complications ( p < 0.001 ) during the perioperative period and a remarkably lower incidence of leukopenia ( p = 0.037 ) during neoadjuvant therapy. In terms of long-term clinical benefit, the RFS of patients in the observation group was evidently longer ( p = 0.037 ) than that in the control group. Conclusion. Compared with TME plus NAC treatment, the short-term and long-term clinical benefits are higher and safety is more favorable of NAC plus bevacizumab combined with TME in treating LARC patients.

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